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Sample records for pylori increases ghrelin

  1. Ghrelin and Helicobacter pylori infection

    Institute of Scientific and Technical Information of China (English)

    Hiroyuki Osawa

    2008-01-01

    Ghrelin is primarily secreted from the stomach and has been implicated in the coordination of eating behavior and weight regulation. Ghrelin also plays an essential role in the mechanism of gastric mucosal defense. Thus, it is important to clarify which diseases primar-ily influence changes in plasma ghrelin concentrations. Helicobacter pylori(H pylori infection is involved in the pathogenesis of gastritis, gastric and duodenal ulcer, gastric carcinoma, and mucosa-associated lym-phoid tissue lymphorna. H pylori eradication is related to body weight change. Compared, H pylori infected and negative subjects with normal body mass index, plasma ghrelin concentration, gastric ghrelin mRNA, and the number of ghrelin producing cells in gastric mucosa are significantly lower in Hpylori injected sub-jects than in H pylori-negative controls. Plasma ghrelin concentration decreases with the progression of gastric atrophy. Impaired gastric ghrelin production in associa-tion with atrophic gastritis induced by Hpylori infection accounts for the decrease in plasma ghrelin concentra-tion. However, the ratio of plasma acylated ghrelin to total ghrelin levels is higher in patients with chronic atrophic gastritis than in healthy subjects. This may re-sult from the compensatory increase in plasma active ghrelin concentration in response to gastric atrophy. After H pylori eradication, gastric preproghrelin mRNA expression is increased nearly 4-fold in most cases. However, changes in plasma ghrelin concentrations be-fore and after H pylori cure are not associated with the gastric ghrelin production. Plasma ghrelin changes are inversely correlated with both body weight change and initial plasma ghrelin levels.

  2. Endocrine impact of Helicobacter pylori : Focus on ghrelin and ghrelin o -acyltransferase

    Institute of Scientific and Technical Information of China (English)

    Penny L Jeffery; Michael A McGuckin; Sara K Linden

    2011-01-01

    Ghrelin is predominantly produced by the gastric enteroendocrine cell compartment and is octanoylated by the recently discovered ghrelin o -acyltransferase (GOAT) before secretion into the bloodstream. This octanoylation is essential for many of the biological properties of ghrelin including appetite stimulation and anti-inflammatory properties as only the acylated form of ghrelin binds to the ghrelin receptor, the growth hormone secretagogue receptor (GHS-R). Given the gastric location of ghrelin production, it is perhaps not surprising that insult to the gastric mucosa affects circulating ghrelin levels in humans. Helicobacter pylori (H. pylori ) infects more than fifty percent of the world's population and once established within the gastric mucosa, can persist for life. Infection is associated with chronic gastritis, gastric atrophy and ulceration, reduced appetite and a lower body mass index (BMI). The large majority of studies investigating levels of circulating ghrelin and ghrelin expression in the stomach in patients with H. pylori infection indicate that the bacterium has a negative impact on ghrelin production and/or secretion. Eradication of infection restores ghrelin, improves appetite and increases BMI in some studies, however, a causative relationship between H. pylori -associated serum ghrelin decline and food intake and obesity has not been established. Most studies measure total ghrelin in the circulation although the measurement of the ratio of acyl/total ghrelin gives a clearer indication that the ghrelin acylation process is altered during infection and atrophy. GOAT is essential for the production of biologically-active, acyl ghrelin and the impact of H. pylori on GOAT expression and activity will be highly informative in the future.

  3. Influence of Helicobacter pylori infection on ghrelin levels in children

    Institute of Scientific and Technical Information of China (English)

    Zhao-Hui Deng; Bo Chu; Ya-Zhen Xu; Bin Zhang; Li-Rong Jiang

    2012-01-01

    AIM:To compare ghrelin levels in plasma and gastric mucosa before and after Helicobacter pylori (H.pylori)treatment in children with H.pylori-associated functional dyspepsia.METHODS:Children with H.pylori-associated functional dyspepsia were enrolled in this study.H.pylori infection was confirmed by positive bacterial culture results.All of the children received triple H.pylori eradication therapy (a 2 wk course of omeprazole,amoxicillin,and clarithromycin).The children were divided into two groups based on the success of the H.pylori treatment:group 1 (eradicated)-patients who had a negative 13C-urea breath test 2 mo after the end of therapy; and group 2 (non-eradicated)-patients who had a positive 13C-urea breath test.Plasma ghrelin,gastric ghrelin mRNA,and the body mass index were evaluated in both groups before and after the H.pylori treatment.The plasma ghrelin levels were measured by a radioimmunoassay.The expression of gastric gnrelin mRNA was determined by real-time reverse transcription polymerase chain reaction.RESULTS:A total of 50 children with H.pylori-associated functional dyspepsia were treated with triple H.pylori eradication therapy.The mean age of the children was 5.52 ± 0.83 years,and there were 28 males and 22 females.Among the 50H.pylori-positive children,30 successfully achieved eradication,and 20 did not.The mean plasma ghrelin levels of group 1 were 22.17 ± 1.73 ng/L and 26.59 ± 2.05 ng/L before and after the treatment,respectively,which was a significant increase (P =0.001).However,the mean plasma ghrelin level of group 2 before and after the H.pylori treatment was 21.34 ± 2.40 ng/L and 22.24 ± 2.10ng/L (P =0.785).The plasma ghrelin levels increased substantially after treatment in group 1 but showed only minor changes in group 2.Similarly,the gastric ghrelin mRNA expression in group 1 before treatment was 2.84 ± 0.08.After treatment,the level was 3.11± 0.65,which was significantly different (P =0.023).The gastric ghrelin m

  4. Gastric ghrelin in relation to gender, stomach topography and Helicobacter pylori in dyspeptic patients

    Institute of Scientific and Technical Information of China (English)

    Krystyna Stec-Michalska; Sebastian Malicki; Blazej Michalski; Lukasz Peczek; Maria Wisniewska-Jarosinska; Barbara Nawrot

    2009-01-01

    AIM: To investigate the level of gastric ghrelin in stomach mucosa of dyspeptic patients in relation to Helicobacter pylori ( H pylori) infection, bacterial cytotoxicity, topography and gender.METHODS: The study comprised 40 premenopausal women (19 H pylori positive) and 48 men (17 H pylori positive) with functional dyspepsia.All gastric biopsy specimens revealed normal mucosa or non-atrophic gastritis.Gastric ghrelin concentration was determined by Enzyme linked immunosorbent assay.The cagA and vacA strains of bacterial DNA were identified by multiplex polymerase chain reaction.RESULTS: In general, infection with H pylori caused an increase in gastric ghrelin level regardless of gender and stomach topography.Significantly more hormone was present in both, non-infected and H pylori positive female samples, as compared to males.The distribution of bacterial strains showed cagA(+) vacA s1m1 and cagA(-) vacA s2m2 genotypes as the most common infections in the studied population.A tendency to higher ghrelin levels was observed in less cytotoxic ( cagA negative) strain-containing specimens from the antrum and corpus of both gender groups (without statistical significance).CONCLUSION: An increase in gastric ghrelin levels at the stage of non-atrophic gastritis in H pylori positive patients, especially in those infected with cagA(-) strains, can exert a gastroprotective effect.

  5. Impact of Helicobacter pylori infection on ghrelin and various neuroendocrine hormones in plasma

    Institute of Scientific and Technical Information of China (English)

    Hajime Isomoto; Hiroaki Ueno; Yoshito Nishi; Chun-Yang Wen; Masamitsu Nakazato; Shigeru Kohno

    2005-01-01

    AIM: Ghrelin, an endogenous ligand for growth hormone secretagogue receptor, influences appetite, energy balance, gastric motility and acid secretion. The stomach is the main source of circulating ghrelin. There are inconsistent reports on the influence of Helicobacter pylori (H pylori) infection on circulating ghrelin levels. We sought to elucidate the relationship between ghrelin and various peptides in plasma, with special reference to H pylori.METHODS: Plasma ghrelin levels were measured by radioimmunoassay in 89 subjects who were referred for upper gastrointestinal endoscopy, consisting of 42 H pylori infected and 47 uninfected ones. Plasma gastrin,somatostatin, leptin, insulin-like growth hormone 1 (IGF-1)and chromogranin A concentrations were also measured.Twelve patients were treated with anti- H pylori regimen.RESULTS: Ghrelin circulating levels were greatly decreased in H pylori-positive than negative individuals (194.2±90.2fmol/mL and 250.4±84.1 respectively, P<0.05), but did not significantly alter following the cure of infection (176.5±79.5 vs 191.3±120.4). There was a significant negative correlation between circulating ghrelin and leptin levels, as well as body mass index, for the whole and uninfected population, but not in H pylori-infected patients. Plasma ghrelin concentrations correlated positively with IGF-1 in H pylori-negative group and negatively with chromogranin A in the infected group.There were no significant correlations among circulating levels of ghrelin, gastrin and somatostatin irrespective of H pylori status.CONCLUSION: H pylori infection influences plasma ghrelin dynamics and its interaction with diverse bioactive peptides involved in energy balance, growth and neuroendocrine function.

  6. Enhanced plasma ghrelin levels in Helicobacter pylori-colonized,interleukin-1-receptor type 1-homozygous knockout (IL-1R1-/-) mice

    Institute of Scientific and Technical Information of China (English)

    Yuka Abiko; Hidekazu Suzuki; Tatsuhiro Masaoka; Sachiko Nomura; Kumiko Kurabayashi; Hiroshi Hosoda; Kenji Kangawa; Toshifumi Hibi

    2005-01-01

    AIM: Ghrelin is an endogenous ligand for the growth hormone secretagogue receptor, and it plays a role in stimulating the growth hormone secretion, food intake,body weight gain and gastric motility. Eradication of Helicobacter pylori(H pylori) was shown to be associated with increase of the body weight. On the other hand, H pylori infection evokes the release of gastric IL-1β. The present study was designed to investigate the involvement of the gastric IL-1 signal in the ghrelin dynamics in H pyloricolonized mice.METHODS: Twelve-week-old female IL-1-receptor type 1-homozygous-knockout mice (IL-1R1-/-) and their wild-type littermates (WT) were orally inoculated with H pylori (Hp group), while other cohorts received oral inoculation of culture medium (Cont group). Thirteen weeks after the inoculation, the mice were examined. The plasma and stomach ghrelin levels and the gastric preproghrelin mRNA were measured.RESULTS: Although the WT mice with H pylori infection showed a significantly decreased body weight as compared with that of the animals without H pylori infection,H pylori infection did not influence the body weight of the IL-1R1-knockout (IL-1R1-/-) mice. In the H pylori-infected IL-1R1-/-mice, the total and active ghrelin levels in the plasma were significantly increased, and the gastric ghrelin level was decreased. No significant differences were noted in the gastric preproghrelin mRNA expression.CONCLUSION: Ghrelin secretion triggered by H pylori infection might be suppressed by IL-1β, the release of which is also induced by the infection, resulting in the body weight loss of mice with H pylori infection.

  7. Influence of H pylori on plasma ghrelin in patients without atrophic gastritis

    Institute of Scientific and Technical Information of China (English)

    Mehmet Cindoruk; Ilhan Yetkin; Serpil Muge Deger; Tarkan Karakan; Erdal Kan; Selahattin Unal

    2007-01-01

    AIM: To determine the association between H pylori infection and serum ghrelin levels in patients without atrophic gastritis.METHODS: Fifty consecutive patients (24 males and 26 females) with either H pylori-positive gastritis (n = 34) or H pylori-negative gastritis (n = 16) with normal gastric acid secretion determined by 24-h pHmetry and without atrophic gastritis in histopathology were enrolled in this study. Thirty-four H pylori-infected patients were treated with triple therapy consisting of a daily regimen of 30 mg lansoprazole bid, 1 g amoxicillin bid and 500 mg clarithromycin bid for 14 d, followed by an additional 4 wk of 30 mg lansoprazol treatment. H pylori infection was eradicated in 23 of 34 (67.6%) patients. H pylori-positive patients were given eradication therapy. Gastric acidity was determined via intragastric pH catethers. Serum ghrelin was measured by radioimmunoassay (RIA).RESULTS: There was no significant difference in plasma ghrelin levels between H pylori -positive and H pylori-negative groups (81.10 ± 162.66 ng/L vs 76.51 ± 122.94 ng/L). In addition, there was no significant difference in plasma ghrelin levels and gastric acidity levels measured before and 3 mo after the eradication therapy.CONCLUSION: H pylori infection does not influence ghrelin secretion in patients with chronic gastritis without atrophic gastritis.

  8. Relationship between ghrelin, Helicobacter pylori and gastric mucosal atrophy in hemodialysis patients.

    Science.gov (United States)

    Ichikawa, Hitomi; Sugimoto, Mitsushige; Sakao, Yukitoshi; Sahara, Shu; Ohashi, Naro; Kato, Akihiko; Sugimoto, Ken; Furuta, Takahisa; Andoh, Akira; Sakao, Tadashi; Yasuda, Hideo

    2016-12-21

    To investigate the relationship between plasma ghrelin level, Helicobacter pylori (H. pylori) infection status and the severity of atrophy in hemodialysis patients. One hundred eights patients who received hemodialysis and 13 non-hemodialysis H. pylori-negative controls underwent gastroduodenoscopy to evaluate the severity of gastric atrophy. Serum levels of pepsinogen (PG) were measured as serum markers of gastric atrophy. H. pylori infection was evaluated by anti-H. pylori IgG antibody, rapid urease test and culture test. We classified H. pylori infection status as non-infection, present infection and past infection. In addition, plasma acyl-ghrelin and desacyl-ghrelin levels were measured by enzyme-linked immunosorbent assay. Infection rate of H. pylori was 45.4% (49/108). Acyl-ghrelin level in the non-infection group (39.4 ± 23.0 fmol/mL) was significantly higher than in the past (23.4 ± 19.9 fmol/mL, P = 0.005) and present infection groups (19.5 ± 14.0 fmol/mL, P atrophy (both P atrophy (24.5 ± 23.1 fmol/mL, 20.2 ± 14.9 fmol/mL and 18.3 ± 11.8 fmol/mL) than in those with non-atrophy (39.4 ± 22.2 fmol/mL, P = 0.039, P = 0.002 and P atrophy related to H. pylori infection.

  9. Ghrelin

    Science.gov (United States)

    Müller, T.D.; Nogueiras, R.; Andermann, M.L.; Andrews, Z.B.; Anker, S.D.; Argente, J.; Batterham, R.L.; Benoit, S.C.; Bowers, C.Y.; Broglio, F.; Casanueva, F.F.; D'Alessio, D.; Depoortere, I.; Geliebter, A.; Ghigo, E.; Cole, P.A.; Cowley, M.; Cummings, D.E.; Dagher, A.; Diano, S.; Dickson, S.L.; Diéguez, C.; Granata, R.; Grill, H.J.; Grove, K.; Habegger, K.M.; Heppner, K.; Heiman, M.L.; Holsen, L.; Holst, B.; Inui, A.; Jansson, J.O.; Kirchner, H.; Korbonits, M.; Laferrère, B.; LeRoux, C.W.; Lopez, M.; Morin, S.; Nakazato, M.; Nass, R.; Perez-Tilve, D.; Pfluger, P.T.; Schwartz, T.W.; Seeley, R.J.; Sleeman, M.; Sun, Y.; Sussel, L.; Tong, J.; Thorner, M.O.; van der Lely, A.J.; van der Ploeg, L.H.T.; Zigman, J.M.; Kojima, M.; Kangawa, K.; Smith, R.G.; Horvath, T.; Tschöp, M.H.

    2015-01-01

    Background The gastrointestinal peptide hormone ghrelin was discovered in 1999 as the endogenous ligand of the growth hormone secretagogue receptor. Increasing evidence supports more complicated and nuanced roles for the hormone, which go beyond the regulation of systemic energy metabolism. Scope of review In this review, we discuss the diverse biological functions of ghrelin, the regulation of its secretion, and address questions that still remain 15 years after its discovery. Major conclusions In recent years, ghrelin has been found to have a plethora of central and peripheral actions in distinct areas including learning and memory, gut motility and gastric acid secretion, sleep/wake rhythm, reward seeking behavior, taste sensation and glucose metabolism. PMID:26042199

  10. Ghrelin

    NARCIS (Netherlands)

    T.D. Müller; R. Nogueiras; M.L. Andermann; Z.B. Andrews; S.D. Anker; J. Argente; R.L. Batterham; S.C. Benoit; C.Y. Bowers; F. Broglio (Fabio); F.F. Casanueva; D. D'Alessio; I. Depoortere; A. Geliebter; E. Ghigo (Ezio); P.A. Cole; M. Cowley; D.E. Cummings; A. Dagher (Alain); S. Diano; S.L. Dickson; C. Dieguez (Carlos); R. Granata (Riccarda); H.J. Grill; K. Grove; K.M. Habegger; K. Heppner; M.L. Heiman; L. Holsen; B. Holst; A. Inui; J.O. Jansson; H. Kirchner; M. Korbonits; B. Laferrère; C.W. LeRoux; M. Lopez; S. Morin; M. Nakazato; R. Nass; D. Perez-Tilve; P.T. Pfluger; T.W. Schwartz; R.J. Seeley; M. Sleeman; Y. Sun (Yuxiang); L. Sussel; J. Tong; M.O. Thorner; A-J. van der Lely (Aart-Jan); L.H.T. van der Ploeg; J.M. Zigman; M. Kojima; K. Kangawa; R.G. Smith (Roy); T. Horvath; M. Tschop (Matthias)

    2015-01-01

    textabstractThe gastrointestinal peptide hormone ghrelin was discovered in 1999 as the endogenous ligand of the growth hormone secretagogue receptor. Increasing evidence supports more complicated and nuanced roles for the hormone, which go beyond the regulation of systemic energy metabolism. Scope o

  11. Ghrelin

    DEFF Research Database (Denmark)

    Mueller, T. D.; Nogueiras, R.; Andermann, M. L.

    2015-01-01

    Background The gastrointestinal peptide hormone ghrelin was discovered in 1999 as the endogenous ligand of the growth hormone secretagogue receptor. Increasing evidence supports more complicated and nuanced roles for the hormone, which go beyond the regulation of systemic energy metabolism. Scope...... areas including learning and memory, gut motility and gastric acid secretion, sleep/wake rhythm, reward seeking behavior, taste sensation and glucose metabolism....

  12. Increased ghrelin but low ghrelin-reactive immunoglobulins in a rat model of methotrexate chemotherapy-induced anorexia

    Directory of Open Access Journals (Sweden)

    Marie François

    2016-07-01

    Full Text Available Background and aims: Cancer chemotherapy is commonly accompanied by mucositis, anorexia, weight loss and anxiety independently from cancer-induced anorexia-cachexia, further aggravating clinical outcome. Ghrelin is a peptide hormone produced in gastric mucosa that reaches the brain to stimulate appetite. In plasma, ghrelin is protected from degradation by ghrelin-reactive immunoglobulins (Ig. To analyze possible involvement of ghrelin in the chemotherapy-induced anorexia and anxiety, gastric ghrelin expression, plasma levels of ghrelin and ghrelin-reactive IgG were studied in rats treated with methotrexate (MTX.Methods: Rats received MTX (2.5 mg/kg, S.C. for three consecutive days and were killed 3 days later, at the peak of anorexia and weight loss. Control rats received phosphate-buffered saline. Preproghrelin mRNA expression in the stomach was analyzed by in situ hybridization. Plasma levels of ghrelin and ghrelin-reactive IgG were measured by immunoenzymatic assays and IgG affinity kinetics by surface plasmon resonance. Anxiety- and depression-like behaviors in MTX-treated anorectic and in control rats were evaluated in the elevated plus-maze and the forced-swim test, respectively.Results: In MTX-treated anorectic rats the number of preproghrelin mRNA-producing cells was found increased (by 51.3%, p<0.001 as well were plasma concentrations of both ghrelin and des-acyl-ghrelin (by 70.4%, p<0.05 and 98.3%, p<0.01, respectively. In contrast, plasma levels of total IgG reactive with ghrelin and des-acyl-ghrelin were drastically decreased (by 87.2% and 88.4%, respectively, both p<0.001, and affinity kinetics of these IgG were characterized by increased small and big Kd, respectively. MTX-treated rats displayed increased anxiety- but not depression-like behavior.Conclusion: MTX-induced anorexia, weight loss and anxiety are accompanied by increased ghrelin production and by a decrease of ghrelin-reactive IgG levels and affinity binding properties

  13. Chronic central administration of Ghrelin increases bone mass through a mechanism independent of appetite regulation.

    Directory of Open Access Journals (Sweden)

    Hyung Jin Choi

    Full Text Available Leptin plays a critical role in the central regulation of bone mass. Ghrelin counteracts leptin. In this study, we investigated the effect of chronic intracerebroventricular administration of ghrelin on bone mass in Sprague-Dawley rats (1.5 μg/day for 21 days. Rats were divided into control, ghrelin ad libitum-fed (ghrelin ad lib-fed, and ghrelin pair-fed groups. Ghrelin intracerebroventricular infusion significantly increased body weight in ghrelin ad lib-fed rats but not in ghrelin pair-fed rats, as compared with control rats. Chronic intracerebroventricular ghrelin infusion significantly increased bone mass in the ghrelin pair-fed group compared with control as indicated by increased bone volume percentage, trabecular thickness, trabecular number and volumetric bone mineral density in tibia trabecular bone. There was no significant difference in trabecular bone mass between the control group and the ghrelin ad-lib fed group. Chronic intracerebroventricular ghrelin infusion significantly increased the mineral apposition rate in the ghrelin pair-fed group as compared with control. In conclusion, chronic central administration of ghrelin increases bone mass through a mechanism that is independent of body weight, suggesting that ghrelin may have a bone anabolic effect through the central nervous system.

  14. Ghrelin

    Directory of Open Access Journals (Sweden)

    T.D. Müller

    2015-06-01

    Major conclusions: In recent years, ghrelin has been found to have a plethora of central and peripheral actions in distinct areas including learning and memory, gut motility and gastric acid secretion, sleep/wake rhythm, reward seeking behavior, taste sensation and glucose metabolism.

  15. Sulfated cholecystokinin-8 increases ghrelin secretion but does not affect oxyntomodulin in Holstein steers.

    Science.gov (United States)

    Yannaing, Swe; Thidarmyint, Hnin; Zhao, Hongqiong; Thanthan, Sint; Kitagawa, Kouki; Kuwayama, Hideto

    2012-08-01

    The effect of appetite regulatory hormone cholecystokinin (CCK) on the secretions of oxyntomodulin (OXM) and ghrelin, and the effect of ghrelin on the secretions of CCK and OXM were studied in ruminants. Eight Holstein steers, 7 months old, 243 ± 7 kg body weight (BW), were arranged in an incomplete Latin square design (8 animals × 4 treatments × 4 days of sampling). Steers were intravenously injected with 10 µg of sulfated CCK-8/kg BW, 20 µg of acyl ghrelin/kg BW, 100 µg of des-acyl ghrelin/kg BW or vehicle. Blood samples were collected from -60 min to 120 min relative to time of injection. Plasma concentrations of ghrelin, sulfated CCK and OXM were measured by double-antibody radioimmunoassay. Plasma acyl ghrelin was increased to peak level (428.3 ± 6 pg/mL) at 60 min after injection of CCK compared with pre-injected levels (203.3 ± 1 pg/mL). These results showed for the first time, that intravenous bolus injection of CCK increased ghrelin secretion in ruminants. In contrast, injection of ghrelin did not change CCK secretion. Administration of ghrelin or CCK has no effect on plasma OXM concentrations. In conclusion, our results show that administration of CCK increased ghrelin secretion but did not affect OXM release in ruminants. Ghrelin did not affect the secretions of CCK and OXM.

  16. Increased plasma ghrelin suppresses insulin release in wethers fed with a high-protein diet.

    Science.gov (United States)

    Takahashi, T; Sato, K; Kato, S; Yonezawa, T; Kobayashi, Y; Ohtani, Y; Ohwada, S; Aso, H; Yamaguchi, T; Roh, S G; Katoh, K

    2014-06-01

    Ghrelin is a multifunctional peptide that promotes an increase of food intake and stimulates GH secretion. Ghrelin secretion is regulated by nutritional status and nutrients. Although a high-protein (HP) diet increases plasma ghrelin secretion in mammals, the mechanisms and the roles of the elevated ghrelin concentrations due to a HP diet have not been fully established. To clarify the roles of elevated acylated ghrelin upon intake of a HP diet, we investigated the regulation of ghrelin concentrations in plasma and tissues in wethers fed with either the HP diet or the control (CNT) diet for 14 days, and examined the action of the elevated plasma ghrelin by using a ghrelin-receptor antagonist. The HP diet gradually increased the plasma acylated-ghrelin concentrations, but the CNT diet did not. Although the GH concentrations did not vary significantly across the groups, an injection of ghrelin-receptor antagonist enhanced insulin levels in circulation in the HP diet group. In the fundus region of the stomach, the ghrelin levels did not differ between the HP and CNT diet groups, whereas ghrelin O-acyltransferase mRNA levels were higher in the group fed with HP diet than those of the CNT diet group were. These results indicate that the HP diet elevated the plasma ghrelin levels by increasing its synthesis; this elevation strongly suppresses the appearance of insulin in the circulation of wethers, but it is not involved in GH secretion. Overall, our findings indicate a role of endogenous ghrelin action in secretion of insulin, which acts as a regulator after the consumption of a HP diet.

  17. In1-ghrelin splicing variant is overexpressed in pituitary adenomas and increases their aggressive features.

    Science.gov (United States)

    Ibáñez-Costa, Alejandro; Gahete, Manuel D; Rivero-Cortés, Esther; Rincón-Fernández, David; Nelson, Richard; Beltrán, Manuel; de la Riva, Andrés; Japón, Miguel A; Venegas-Moreno, Eva; Gálvez, Ma Ángeles; García-Arnés, Juan A; Soto-Moreno, Alfonso; Morgan, Jennifer; Tsomaia, Natia; Culler, Michael D; Dieguez, Carlos; Castaño, Justo P; Luque, Raúl M

    2015-03-04

    Pituitary adenomas comprise a heterogeneous subset of pathologies causing serious comorbidities, which would benefit from identification of novel, common molecular/cellular biomarkers and therapeutic targets. The ghrelin system has been linked to development of certain endocrine-related cancers. Systematic analysis of the presence and functional implications of some components of the ghrelin system, including native ghrelin, receptors and the recently discovered splicing variant In1-ghrelin, in human normal pituitaries (n = 11) and pituitary adenomas (n = 169) revealed that expression pattern of ghrelin system suffers a clear alteration in pituitary adenomasas compared with normal pituitary, where In1-ghrelin is markedly overexpressed. Interestingly, in cultured pituitary adenoma cells In1-ghrelin treatment (acylated peptides at 100 nM; 24-72 h) increased GH and ACTH secretion, Ca(2+) and ERK1/2 signaling and cell viability, whereas In1-ghrelin silencing (using a specific siRNA; 100 nM) reduced cell viability. These results indicate that an alteration of the ghrelin system, specially its In1-ghrelin variant, could contribute to pathogenesis of different pituitary adenomas types, and suggest that this variant and its related ghrelin system could provide new tools to identify novel, more general diagnostic, prognostic and potential therapeutic targets in pituitary tumors.

  18. Interferon-γ inhibits ghrelin expression and secretion via a somatostatin-mediated mechanism

    Institute of Scientific and Technical Information of China (English)

    Jesper AB Strickertsson; Kristina BV Dφssing; Anna JM Aabakke; Hans-Olof Nilsson; Thomas VO Hansen; Ulrich Knigge; Andreas Kj(ae)r; Torkel Wadstr(o)m; Lennart Friis-Hansen

    2011-01-01

    AIM: To investigate if and how the proinflammatory cytokine interferon γ (IFNγ) affects ghrelin expression in mice. METHODS: The plasma concentration of ghrelin, and gastric ghrelin and somatostatin expression, were examined in wild-type mice and mice infected with Helicobacter pylori (H. pylori ). Furthermore, ghrelin expression was examined in two achlorhydric mouse models with varying degrees of gastritis due to bacterial overgrowth. To study the effect of IFNγ alone, mice were given a subcutaneous infusion of IFNγ for 7 d. Finally, the influence of IFNγ and somatostatin on the ghrelin promoter was characterized. RESULTS: H. pylori infection was associated with a 50% reduction in ghrelin expression and plasma concentration. Suppression of ghrelin expression was inversely correlated with gastric inflammation in achlorhdyric mouse models. Subcutaneous infusion of IFNγ suppressed fundic ghrelin mRNA expression and plasma ghrelin concentrations. Finally, we showed that the ghrelin promoter operates under the control of somatostatin but not under that of IFNγ. CONCLUSION: Gastric infection and inflammation is associated with increased IFNγ expression and reduced ghrelin expression. IFNγ does not directly control ghrelin expression but inhibits it indirectly via somatostatin.

  19. Stress increased ghrelin secretion from pancreatic isolated islets in male rats.

    Science.gov (United States)

    Rostamkhani, Fatemeh; Zardooz, Homeira; Goshadrou, Fatemeh; Baveisi, Mahyar; Hedayati, Mehdi

    2016-01-01

    It has been demonstrated that plasma ghrelin is likely affected by stress, but little attention has been paid to the effect of stress on ghrelin release from pancreatic islets. This study investigates the effect of stress on ghrelin secretion from pancreatic islets in rats. Male Wistar rats were divided into control and stressed groups. The stressed group was further divided into foot-shock and psychological stress subgroups. Stress was induced by a communication box. After stress exposure, blood sampling was performed to determine the plasma levels of corticosterone, glucose, and ghrelin. Then the animals' pancreatic islets were isolated to assess their ghrelin output at 5.6, 8.3, and 16.7 mM glucose concentrations. Acute exposure to foot-shock and psychological stress both increased plasma corticosterone concentration. Moreover, plasma glucose concentration increased in the foot-shock stress group. Chronic exposure to foot-shock decreased plasma ghrelin concentration, whereas acute exposure had no significant effect. Acute and chronic exposure to foot-shock and psychological stress increased ghrelin secretion from isolated islets in the presence of different glucose concentrations. The results of the present study suggest that ghrelin secretion from isolated islets is not glucose-dependent. However, ghrelin secretion appears to be intensely responsive to both acute and chronic stress.

  20. Helicobacter pylori and nonmalignant diseases.

    LENUS (Irish Health Repository)

    Alakkari, Alaa

    2012-02-01

    Research published over the past year has documented the continued decline of Helicobacter pylori-related peptic ulcer disease and increased recognition of non-H. pylori, non-steroidal anti-inflammatory drugs ulcer disease--idiopathic ulcers. Despite reduced prevalence of uncomplicated PUD, rates of ulcer complications and associated mortality remain stubbornly high. The role of H. pylori in functional dyspepsia is unclear, with some authors considering H. pylori-associated nonulcer dyspepsia a distinct organic entity. There is increasing acceptance of an inverse relationship between H. pylori and gastroesophageal reflux disease (GERD), but little understanding of how GERD might be more common\\/severe in H. pylori-negative subjects. Research has focused on factors such as different H. pylori phenotypes, weight gain after H. pylori eradication, and effects on hormones such as ghrelin that control appetite.

  1. Ghrelin increases the motivation to eat, but does not alter food palatability.

    Science.gov (United States)

    Overduin, Joost; Figlewicz, Dianne P; Bennett-Jay, Jennifer; Kittleson, Sepideh; Cummings, David E

    2012-08-01

    Homeostatic eating cannot explain overconsumption of food and pathological weight gain. A more likely factor promoting excessive eating is food reward and its representation in the central nervous system (CNS). The anorectic hormones leptin and insulin reduce food reward and inhibit related CNS reward pathways. Conversely, the orexigenic gastrointestinal hormone ghrelin activates both homeostatic and reward-related neurocircuits. The current studies were conducted to identify in rats the effects of intracerebroventricular ghrelin infusions on two distinct aspects of food reward: hedonic valuation (i.e., "liking") and the motivation to self-administer (i.e., "wanting") food. To assess hedonic valuation of liquid food, lick motor patterns were recorded using lickometry. Although ghrelin administration increased energy intake, it did not alter the avidity of licking (initial lick rates or lick-cluster size). Several positive-control conditions ruled out lick-rate ceiling effects. Similarly, when the liquid diet was hedonically devalued with quinine supplementation, ghrelin failed to reverse the quinine-associated reduction of energy intake and avidity of licking. The effects of ghrelin on rats' motivation to eat were assessed using lever pressing to self-administer food in a progressive-ratio paradigm. Ghrelin markedly increased motivation to eat, to levels comparable to or greater than those seen following 24 h of food deprivation. Pretreatment with the dopamine D1 receptor antagonist SCH-23390 eliminated ghrelin-induced increases in lever pressing, without compromising generalized licking motor control, indicating a role for D1 signaling in ghrelin's motivational feeding effects. These results indicate that ghrelin increases the motivation to eat via D1 receptor-dependent mechanisms, without affecting perceived food palatability.

  2. Negative energy balance increases periprandial ghrelin and growth hormone concentrations in lactating dairy cows.

    Science.gov (United States)

    Bradford, Barry J; Allen, Michael S

    2008-02-01

    The reported effects of feeding on growth hormone (GH) secretion in ruminants have been inconsistent, and are likely influenced by energy status of animals. High-producing dairy cows in early lactation and late lactation were used to assess the effects of energy balance on temporal variation of plasma metabolites and hormones. Cows were fed a single diet once daily, and feed was withdrawn for 90 min prior to feeding. Beginning at the time of feed withdrawal, plasma samples were collected via jugular catheters hourly for 24h. Concentrations of non-esterified fatty acids and GH were measured for all samples, while insulin, glucose, and acylated (active) ghrelin were quantified for four sample times around feeding. As expected, calculated energy balance was significantly lower in early lactation than late lactation cows (-43.5 MJ retained/day versus 7.2 MJ retained/day). Following the primary meal of the day, a GH surge was observed in early lactation but not in late lactation cows. This difference was not explained by temporal patterns in non-esterified fatty acid, insulin, or glucose concentrations. However, a preprandial ghrelin surge was observed in early lactation only, suggesting that ghrelin was responsible for the prandial GH surge in this group. Results of a stepwise regression statistical analysis showed that both preprandial ghrelin concentration and energy balance were significant predictors of prandial GH increase over baseline. Adaptations to negative energy balance in lactating dairy cattle likely include enhanced ghrelin secretion and greater GH response to ghrelin.

  3. Dietary Caprylic Acid (C8:0) Does Not Increase Plasma Acylated Ghrelin but Decreases Plasma Unacylated Ghrelin in the Rat.

    Science.gov (United States)

    Lemarié, Fanny; Beauchamp, Erwan; Dayot, Stéphanie; Duby, Cécile; Legrand, Philippe; Rioux, Vincent

    2015-01-01

    Focusing on the caprylic acid (C8:0), this study aimed at investigating the discrepancy between the formerly described beneficial effects of dietary medium chain fatty acids on body weight loss and the C8:0 newly reported effect on food intake via ghrelin octanoylation. During 6 weeks, Sprague-Dawley male rats were fed with three dietary C8:0 levels (0, 8 and 21% of fatty acids) in three experimental conditions (moderate fat, caloric restriction and high fat). A specific dose-response enrichment of the stomach tissue C8:0 was observed as a function of dietary C8:0, supporting the hypothesis of an early preduodenal hydrolysis of medium chain triglycerides and a direct absorption at the gastric level. However, the octanoylated ghrelin concentration in the plasma was unchanged in spite of the increased C8:0 availability. A reproducible decrease in the plasma concentration of unacylated ghrelin was observed, which was consistent with a decrease in the stomach preproghrelin mRNA and stomach ghrelin expression. The concomitant decrease of the plasma unacylated ghrelin and the stability of its acylated form resulted in a significant increase in the acylated/total ghrelin ratio which had no effect on body weight gain or total dietary consumption. This enhanced ratio measured in rats consuming C8:0 was however suspected to increase (i) growth hormone (GH) secretion as an increase in the GH-dependent mRNA expression of the insulin like growth Factor 1 (IGF-1) was measured (ii) adipocyte diameters in subcutaneous adipose tissue without an increase in the fat pad mass. Altogether, these results show that daily feeding with diets containing C8:0 increased the C8:0 level in the stomach more than all the other tissues, affecting the acylated/total ghrelin plasma ratio by decreasing the concentration of circulating unacylated ghrelin. However, these modifications were not associated with increased body weight or food consumption.

  4. Dietary Caprylic Acid (C8:0 Does Not Increase Plasma Acylated Ghrelin but Decreases Plasma Unacylated Ghrelin in the Rat.

    Directory of Open Access Journals (Sweden)

    Fanny Lemarié

    Full Text Available Focusing on the caprylic acid (C8:0, this study aimed at investigating the discrepancy between the formerly described beneficial effects of dietary medium chain fatty acids on body weight loss and the C8:0 newly reported effect on food intake via ghrelin octanoylation. During 6 weeks, Sprague-Dawley male rats were fed with three dietary C8:0 levels (0, 8 and 21% of fatty acids in three experimental conditions (moderate fat, caloric restriction and high fat. A specific dose-response enrichment of the stomach tissue C8:0 was observed as a function of dietary C8:0, supporting the hypothesis of an early preduodenal hydrolysis of medium chain triglycerides and a direct absorption at the gastric level. However, the octanoylated ghrelin concentration in the plasma was unchanged in spite of the increased C8:0 availability. A reproducible decrease in the plasma concentration of unacylated ghrelin was observed, which was consistent with a decrease in the stomach preproghrelin mRNA and stomach ghrelin expression. The concomitant decrease of the plasma unacylated ghrelin and the stability of its acylated form resulted in a significant increase in the acylated/total ghrelin ratio which had no effect on body weight gain or total dietary consumption. This enhanced ratio measured in rats consuming C8:0 was however suspected to increase (i growth hormone (GH secretion as an increase in the GH-dependent mRNA expression of the insulin like growth Factor 1 (IGF-1 was measured (ii adipocyte diameters in subcutaneous adipose tissue without an increase in the fat pad mass. Altogether, these results show that daily feeding with diets containing C8:0 increased the C8:0 level in the stomach more than all the other tissues, affecting the acylated/total ghrelin plasma ratio by decreasing the concentration of circulating unacylated ghrelin. However, these modifications were not associated with increased body weight or food consumption.

  5. Ghrelin Administration Increases the Bax/Bcl-2 Gene Expression Ratio in the Heart of Chronic Hypoxic Rats.

    Science.gov (United States)

    Aliparasti, Mohammad Reza; Alipour, Mohammad Reza; Almasi, Shohreh; Feizi, Hadi

    2015-06-01

    Programmed cell death or apoptosis, is a biochemical procedure that initiates due to some conditions, including hypoxia. Bax and Bcl-2 are among the agents that regulate apoptosis. The amplification of the first one triggers the initiation of apoptosis, and the second one prevents it. Ghrelin is an endogenous peptide that antiapoptosis is its new effect. The aim of this study is to examine the effect of ghrelin on the Bax/Bcl-2 ratio. Twenty four wistar rats were divided randomly in three groups; control, hypoxic + saline and hypoxic + ghrelin. Hypoxic animals lived in O2 11% for 2 weeks and received either saline or ghrelin subcutaneously daily. The bax and Bcl-2 gene expression were measured by Real-Time RT-PCR. Chronic hypoxia increased the Bax gene expression significantly compared with normal animals (P = 0.008), but the Bcl-2 was not affected by hypoxia. The Bax/Bcl-2 ratio also amplified significantly (P=0.005). Ghrelin administration significantly increased the Bax/Bcl-2 ratio in the hypoxic animals compared to the hypoxic + saline and normal groups (p=0.042 and P= 0.001, respectively). In the present study, animals' treatment with ghrelin leads to an increment of Bax/Bcl-2 ratio, which indicates a controversy related to cardioprotection of ghrelin.

  6. Ghrelin Administration Increases the Bax/Bcl-2 Gene Expression Ratio in the Heart of Chronic Hypoxic Rats

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Aliparasti

    2015-06-01

    Full Text Available Purpose: Programmed cell death or apoptosis, is a biochemical procedure that initiates due to some conditions, including hypoxia. Bax and Bcl-2 are among the agents that regulate apoptosis. The amplification of the first one triggers the initiation of apoptosis, and the second one prevents it. Ghrelin is an endogenous peptide that antiapoptosis is its new effect. The aim of this study is to examine the effect of ghrelin on the Bax/Bcl-2 ratio. Methods: Twenty four wistar rats were divided randomly in three groups; control, hypoxic + saline and hypoxic + ghrelin. Hypoxic animals lived in O2 11% for 2 weeks and received either saline or ghrelin subcutaneously daily. The bax and Bcl-2 gene expression were measured by Real-Time RT-PCR. Results: Chronic hypoxia increased the Bax gene expression significantly compared with normal animals (P = 0.008, but the Bcl-2 was not affected by hypoxia. The Bax/Bcl-2 ratio also amplified significantly (P=0.005. Ghrelin administration significantly increased the Bax/Bcl-2 ratio in the hypoxic animals compared to the hypoxic + saline and normal groups (p=0.042 and P= 0.001, respectively. Conclusion: In the present study, animals’ treatment with ghrelin leads to an increment of Bax/Bcl-2 ratio, which indicates a controversy related to cardioprotection of ghrelin.

  7. Ghrelin Administration Increases the Bax/Bcl-2 Gene Expression Ratio in the Heart of Chronic Hypoxic Rats

    Science.gov (United States)

    Aliparasti, Mohammad Reza; Alipour, Mohammad Reza; Almasi, Shohreh; Feizi, Hadi

    2015-01-01

    Purpose: Programmed cell death or apoptosis, is a biochemical procedure that initiates due to some conditions, including hypoxia. Bax and Bcl-2 are among the agents that regulate apoptosis. The amplification of the first one triggers the initiation of apoptosis, and the second one prevents it. Ghrelin is an endogenous peptide that antiapoptosis is its new effect. The aim of this study is to examine the effect of ghrelin on the Bax/Bcl-2 ratio. Methods: Twenty four wistar rats were divided randomly in three groups; control, hypoxic + saline and hypoxic + ghrelin. Hypoxic animals lived in O2 11% for 2 weeks and received either saline or ghrelin subcutaneously daily. The bax and Bcl-2 gene expression were measured by Real-Time RT-PCR. Results: Chronic hypoxia increased the Bax gene expression significantly compared with normal animals (P = 0.008), but the Bcl-2 was not affected by hypoxia. The Bax/Bcl-2 ratio also amplified significantly (P=0.005). Ghrelin administration significantly increased the Bax/Bcl-2 ratio in the hypoxic animals compared to the hypoxic + saline and normal groups (p=0.042 and P= 0.001, respectively). Conclusion: In the present study, animals’ treatment with ghrelin leads to an increment of Bax/Bcl-2 ratio, which indicates a controversy related to cardioprotection of ghrelin. PMID:26236657

  8. Plasma Ghrelin Concentrations Were Altered with Oestrous Cycle Stage and Increasing Age in Reproductively Competent Wistar Females

    Science.gov (United States)

    Saffrey, M. Jill; Taylor, Victoria J.

    2016-01-01

    Changes in appetite occur during the ovarian cycle in female mammals. Research on appetite-regulatory gastrointestinal peptides in females is limited, because reproductive changes in steroid hormones present additional experimental factors to control for. This study aimed to explore possible changes in the orexigenic (appetite-stimulating) gastrointestinal peptide hormone ghrelin during the rodent oestrous cycle. Fed and fasted plasma and stomach tissue samples were taken from female Wistar rats (32–44 weeks of age) at each stage of the oestrous cycle for total ghrelin quantification using radioimmunoassay. Sampling occurred during the dark phase when most eating takes place in rats. Statistical analysis was by paired-samples t-test, one-way ANOVA on normally distributed data, with Tukey post-hoc tests, or Kruskal-Wallis if not. GLM univariate analysis was used to assess main effects and interactions in ghrelin concentrations in the fed or fasted state and during different stages of the ovarian cycle, with age as a covariate. No consistent fed to fasted ghrelin increases were measured in matched plasma samples from the same animals, contrary to expectations. Total ghrelin concentrations did not significantly change between cycle stages with ANOVA, in either fed or fasted plasma or in stomach tissue. This was despite significantly decreased fasted stomach contents at oestrus (P = 0.028), suggesting decreased food intake. There was however a significant interaction in ghrelin plasma concentrations between fed and fasted proestrus rats and a direct effect of age with rats over 37 weeks old having lower circulating concentrations of ghrelin in both fed and fasted states. The biological implications of altered ghrelin plasma concentrations from 37 weeks of age are as yet unknown, but warrant further investigation. Exploring peripheral ghrelin regulatory factor changes with increasing age in reproductively competent females may bring to light potential effects on

  9. Novel and Effective Therapeutic Regimens for Helicobacter pylori in an Era of Increasing Antibiotic Resistance

    Directory of Open Access Journals (Sweden)

    Yi Hu

    2017-05-01

    Full Text Available Helicobacter pylori (H. pylori is a common gastrointestinal bacterial strain closely associated with the incidence of chronic gastritis, peptic ulcers, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. A current research and clinical challenge is the increased rate of antibiotic resistance in H. pylori, which has led to a decreased H. pylori eradication rate. In this article, we review recent H. pylori infection and reinfection rates and H. pylori resistance to antibiotics, and we discuss the pertinent treatments. A PubMed literature search was performed using the following keywords: Helicobacter pylori, infection, reinfection, antibiotic resistance, bismuth, proton pump inhibitors, vonoprazan, susceptibility, quintuple therapy, dual therapy, and probiotic. The prevalence of H. pylori has remained high in some areas despite the decreasing trend of H. pylori prevalence observed over time. Additionally, the H. pylori reinfection rate has varied in different countries due to socioeconomic and hygienic conditions. Helicobacter pylori monoresistance to clarithromycin, metronidazole or levofloxacin was common in most countries. However, the prevalence of amoxicillin and tetracycline resistance has remained low. Because H. pylori infection and reinfection present serious challenges and because H. pylori resistance to clarithromycin, metronidazole or levofloxacin remains high in most countries, the selection of an efficient regimen to eradicate H. pylori is critical. Currently, bismuth-containing quadruple therapies still achieve high eradication rates. Moreover, susceptibility-based therapies are alternatives because they may avoid the use of unnecessary antibiotics. Novel regimens, e.g., vonoprazan-containing triple therapies, quintuple therapies, high-dose dual therapies, and standard triple therapies with probiotics, require further studies concerning their efficiency and safety for treating H. pylori.

  10. Novel and Effective Therapeutic Regimens for Helicobacter pylori in an Era of Increasing Antibiotic Resistance

    Science.gov (United States)

    Hu, Yi; Zhu, Yin; Lu, Nong-Hua

    2017-01-01

    Helicobacter pylori (H. pylori) is a common gastrointestinal bacterial strain closely associated with the incidence of chronic gastritis, peptic ulcers, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. A current research and clinical challenge is the increased rate of antibiotic resistance in H. pylori, which has led to a decreased H. pylori eradication rate. In this article, we review recent H. pylori infection and reinfection rates and H. pylori resistance to antibiotics, and we discuss the pertinent treatments. A PubMed literature search was performed using the following keywords: Helicobacter pylori, infection, reinfection, antibiotic resistance, bismuth, proton pump inhibitors, vonoprazan, susceptibility, quintuple therapy, dual therapy, and probiotic. The prevalence of H. pylori has remained high in some areas despite the decreasing trend of H. pylori prevalence observed over time. Additionally, the H. pylori reinfection rate has varied in different countries due to socioeconomic and hygienic conditions. Helicobacter pylori monoresistance to clarithromycin, metronidazole or levofloxacin was common in most countries. However, the prevalence of amoxicillin and tetracycline resistance has remained low. Because H. pylori infection and reinfection present serious challenges and because H. pylori resistance to clarithromycin, metronidazole or levofloxacin remains high in most countries, the selection of an efficient regimen to eradicate H. pylori is critical. Currently, bismuth-containing quadruple therapies still achieve high eradication rates. Moreover, susceptibility-based therapies are alternatives because they may avoid the use of unnecessary antibiotics. Novel regimens, e.g., vonoprazan-containing triple therapies, quintuple therapies, high-dose dual therapies, and standard triple therapies with probiotics, require further studies concerning their efficiency and safety for treating H. pylori. PMID:28529929

  11. Ghrelin inhibits proliferation and increases T-type Ca{sup 2+} channel expression in PC-3 human prostate carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Lezama, Nundehui; Hernandez-Elvira, Mariana [Laboratory of Neuroendocrinology, Institute of Physiology, Autonomous University of Puebla (BUAP), Puebla (Mexico); Sandoval, Alejandro [School of Medicine FES Iztacala, National Autonomous University of Mexico (UNAM), Tlalnepantla (Mexico); Monroy, Alma; Felix, Ricardo [Department of Cell Biology, Center for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav-IPN), Mexico City (Mexico); Monjaraz, Eduardo, E-mail: emguzman@siu.buap.mx [Laboratory of Neuroendocrinology, Institute of Physiology, Autonomous University of Puebla (BUAP), Puebla (Mexico)

    2010-12-03

    Research highlights: {yields} Ghrelin decreases prostate carcinoma PC-3 cells proliferation. {yields} Ghrelin favors apoptosis in PC-3 cells. {yields} Ghrelin increase in intracellular free Ca{sup 2+} levels in PC-3 cells. {yields} Grelin up-regulates expression of T-type Ca{sup 2+} channels in PC-3 cells. {yields} PC-3 cells express T-channels of the Ca{sub V}3.1 and Ca{sub V}3.2 subtype. -- Abstract: Ghrelin is a multifunctional peptide hormone with roles in growth hormone release, food intake and cell proliferation. With ghrelin now recognized as important in neoplastic processes, the aim of this report is to present findings from a series of in vitro studies evaluating the cellular mechanisms involved in ghrelin regulation of proliferation in the PC-3 human prostate carcinoma cells. The results showed that ghrelin significantly decreased proliferation and induced apoptosis. Consistent with a role in apoptosis, an increase in intracellular free Ca{sup 2+} levels was observed in the ghrelin-treated cells, which was accompanied by up-regulated expression of T-type voltage-gated Ca{sup 2+} channels. Interestingly, T-channel antagonists were able to prevent the effects of ghrelin on cell proliferation. These results suggest that ghrelin inhibits proliferation and may promote apoptosis by regulating T-type Ca{sup 2+} channel expression.

  12. Anxiolytic-Like Effects of Increased Ghrelin Receptor Signaling in the Amygdala

    DEFF Research Database (Denmark)

    Jensen, Morten; Ratner, Cecilia; Rudenko, Olga;

    2016-01-01

    BACKGROUND: Besides the well-known effects of ghrelin on adiposity and food intake regulation, the ghrelin system has been shown to regulate aspects of behavior including anxiety and stress. However, the effect of virus-mediated overexpression of the ghrelin receptor in the amygdala has not previ......BACKGROUND: Besides the well-known effects of ghrelin on adiposity and food intake regulation, the ghrelin system has been shown to regulate aspects of behavior including anxiety and stress. However, the effect of virus-mediated overexpression of the ghrelin receptor in the amygdala has...... overexpression on anxiety-related behavior before and after acute stress and measured the modulation of serotonin receptor expression. RESULTS: We found that ghrelin caused an anxiolytic-like effect in both the open field and elevated plus maze tests. Additionally, it attenuated air-puff induced stress...... axis potentially engaging the central serotonin system....

  13. Aspirin increases susceptibility of Helicobacter pylori to metronidazole by augmenting endocellular concentrations of antimicrobials

    Institute of Scientific and Technical Information of China (English)

    Xiao-Ping Zhang; Wei-Hong Wang; Yu Tian; Wen Gao; Jiang Li

    2009-01-01

    AIM: To investigate the mechanisms of aspirin increasing the susceptibility of Helicobacter pylori ( H pylori) to metronidazole. METHODS: H pylori reference strain 26 695 and two metronidazole-resistant isolates of H pylori were included in this study. Strains were incubated in Brucella broth with or without aspirin (1 mmol/L). The rdxA gene of H pylori was amplified by PCR and sequenced. The permeability of H pylori to antimicrobials was determined by analyzing the endocellular radioactivity of the cells after incubated with [7-3H]-tetracycline. The outer membrane proteins (OMPs) of H pylori 26 695 were depurated and analyzed by SDS-PAGE. The expression of 5 porins (hopA, hopB, hopC, hopD and hopE) and the putative RND efflux system (hefABC) of H pylori were analyzed using real-time quantitative PCR. RESULTS: The mutations in rdxA gene did not change in metronidazole resistant isolates treated with aspirin. The radioactivity of H pylori increased when treated with aspirin, indicating that aspirin improved the permeability of the outer membrane of H pylori. However, the expression of two OMP bands between 55 kDa and 72 kDa altered in the presence of aspirin. The expression of the mRNA of hopA, hopB, hopC, hopD, hopE and hefA, hefB, hefC of H pylori did not change when treated with aspirin. CONCLUSION: Although aspirin increases the susceptibility of H pylori to metronidazole, it has no effect on the mutations of rdxA gene of H pylori. Aspirin increases endocellular concentrations of antimicrobials probably by altering the OMP expression.

  14. The Role of H. pylori CagA in Regulating Hormones of Functional Dyspepsia Patients

    Directory of Open Access Journals (Sweden)

    Wang-Ping Meng

    2016-01-01

    Full Text Available Helicobacter pylori (H. pylori, Hp colonizes the stomachs of approximately 20%–80% of humans throughout the world. The Word Healthy Organization (WHO classified H. pylori as a group 1 carcinogenic factor in 1994. Recently, an increasing number of studies has shown an association between H. pylori infection and various extragastric diseases. Functional dyspepsia (FD is considered a biopsychosocial disorder with multifactorial pathogenesis, and studies have shown that infection with CagA-positive H. pylori strains could explain some of the symptoms of functional dyspepsia. Moreover, CagA-positive H. pylori strains have been shown to affect the secretion of several hormones, including 5-HT, ghrelin, dopamine, and gastrin, and altered levels of these hormones might be the cause of the psychological disorders of functional dyspepsia patients. This review describes the mutual effects of H. pylori and hormones in functional dyspepsia and provides new insight into the pathogenesis of functional dyspepsia.

  15. DESACYL GHRELIN INHIBITS THE OREXIGENIC EFFECT OF PERIPHERALLY INJECTED GHRELIN IN RATS

    Science.gov (United States)

    Inhoff, Tobias; Mönnikes, Hubert; Noetzel, Steffen; Stengel, Andreas; Goebel, Miriam; Dinh, Q. Thai; Riedl, Andrea; Bannert, Norbert; Wisser, Anna-Sophia; Wiedenmann, Bertram; Klapp, Burghard F.; Taché, Yvette

    2008-01-01

    Studies showed that the metabolic unlike the neuroendocrine effects of ghrelin could be abrogated by co-administered unacylated ghrelin. The aim was to investigate the interaction between ghrelin and desacyl ghrelin administered intraperitoneally on food intake and neuronal activity (c-Fos) in the arcuate nucleus in non-fasted rats. Ghrelin (13 μg/kg) significantly increased food intake within the first 30 min post injection. Desacyl ghrelin at 64 and 127 μg/kg injected simultaneously with ghrelin abolished the stimulatory effect of ghrelin on food intake. Desacyl ghrelin alone at both doses did not alter food intake. Both doses of desacyl ghrelin injected separately in the light phase had no effects on food intake when rats were fasted for 12 h. Ghrelin and desacyl ghrelin (64 μg/kg) injected alone increased the number of Fos positive neurons in the arcuate nucleus compared to vehicle. The effect on neuronal activity induced by ghrelin was significantly reduced when injected simultaneously with desacyl ghrelin. Double labeling revealed that nesfatin-1 immunoreactive neurons in the arcuate nucleus are activated by simultaneous injection of ghrelin and desacyl ghrelin. These results suggest that desacyl ghrelin suppresses ghrelin-induced food intake by curbing ghrelin-induced increased neuronal activity in the arcuate nucleus and recruiting nesfatin-1 immunopositive neurons. PMID:18938204

  16. Ghrelin and gastric acid secretion

    Institute of Scientific and Technical Information of China (English)

    Koji Yakabi; Junichi Kawashima; Shingo Kato

    2008-01-01

    Ghrelin, a novel growth hormone-releasing peptide, was originally isolated from rat and human stomach. Ghrelin has been known to increase the secretion of growth hormone (GH), food intake, and body weight gain when administered peripherally or centrally. Ghrelin is also known to stimulate the gastric motility and the secretion of gastric acid. In the previous studies, the action of ghrelin on acid secretion was shown to be as strong as that of histamine and gastrin in-vivo experiment. In the studies, the mechanism for the action of ghrelin was also investigated. It was shown that vagotomy completely inhibited the action of ghrelin on the secretion of gastric acid suggesting that vagal nerve is involved in the mechanism for the action of ghrelin on acid secretion. As famotidine did not inhibit ghrelin-in-duced acid secretion in the study by Masuda et al, they concluded that histamine was not involved in the action of ghrelin on acid secretion. However, we have shown that famotidine completely inhibited ghrelin-induced acid secretion and histidine decarboxylase (HDC) mRNA was increased in gastric mucosa by ghrelin injection which is inhibited by vagotomy Our results indicate that histamine is involved in the action of ghrelin on acid secretion. Furthermore synergistic action of gastrin and ghrelin on gastric add secretion was shown. Although gastrin has important roles in postprandial secretion of gastric acid, ghrelin may be related to acid secretion during fasting period or at night. However, further studies are needed to elucidate the physiological role of ghrelin in acid secretion.

  17. Ghrelin and gastric acid secretion.

    Science.gov (United States)

    Yakabi, Koji; Kawashima, Junichi; Kato, Shingo

    2008-11-07

    Ghrelin, a novel growth hormone-releasing peptide, was originally isolated from rat and human stomach. Ghrelin has been known to increase the secretion of growth hormone (GH), food intake, and body weight gain when administered peripherally or centrally. Ghrelin is also known to stimulate the gastric motility and the secretion of gastric acid. In the previous studies, the action of ghrelin on acid secretion was shown to be as strong as that of histamine and gastrin in in-vivo experiment. In the studies, the mechanism for the action of ghrelin was also investigated. It was shown that vagotomy completely inhibited the action of ghrelin on the secretion of gastric acid suggesting that vagal nerve is involved in the mechanism for the action of ghrelin on acid secretion. As famotidine did not inhibit ghrelin-induced acid secretion in the study by Masuda et al, they concluded that histamine was not involved in the action of ghrelin on acid secretion. However, we have shown that famotidine completely inhibited ghrelin-induced acid secretion and histidine decarboxylase (HDC) mRNA was increased in gastric mucosa by ghrelin injection which is inhibited by vagotomy Our results indicate that histamine is involved in the action of ghrelin on acid secretion. Furthermore synergistic action of gastrin and ghrelin on gastric acid secretion was shown. Although gastrin has important roles in postprandial secretion of gastric acid, ghrelin may be related to acid secretion during fasting period or at night. However, further studies are needed to elucidate the physiological role of ghrelin in acid secretion.

  18. Ghrelin reverses experimental diabetic neuropathy in mice

    Energy Technology Data Exchange (ETDEWEB)

    Kyoraku, Itaru; Shiomi, Kazutaka [Division of Neurology, Respirology, Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, Kiyotake, Miyazaki 889-1692 (Japan); Kangawa, Kenji [Department of Biochemistry, National Cardiovascular Center Research Institute, Osaka 565-8565 (Japan); Nakazato, Masamitsu, E-mail: nakazato@med.miyazaki-u.ac.jp [Division of Neurology, Respirology, Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, Kiyotake, Miyazaki 889-1692 (Japan)

    2009-11-20

    Ghrelin, an acylated peptide produced in the stomach, increases food intake and growth hormone secretion, suppresses inflammation and oxidative stress, and promotes cell survival and proliferation. We investigated the pharmacological potential of ghrelin in the treatment of polyneuropathy in uncontrolled streptozotocin (STZ)-induced diabetes in mice. Ghrelin or desacyl-ghrelin was administered daily for 4 weeks after STZ-induced diabetic polyneuropathy had developed. Ghrelin administration did not alter food intake, body weight gain, blood glucose levels, or plasma insulin levels when compared with mice given saline or desacyl-ghrelin administration. Ghrelin administration ameliorated reductions in motor and sensory nerve conduction velocities in diabetic mice and normalized their temperature sensation and plasma concentrations of 8-isoprostaglandin {alpha}, an oxidative stress marker. Desacyl-ghrelin failed to have any effect. Ghrelin administration in a mouse model of diabetes ameliorated polyneuropathy. Thus, ghrelin's effects represent a novel therapeutic paradigm for the treatment of this otherwise intractable disorder.

  19. Lansoprazole increases serum IgG and IgM in H. pylori-infected patients.

    Science.gov (United States)

    Matsukawa, Y; Kurosaka, H; Kato, K; Hayashi, I; Minekawa, K; Arakawa, Y; Sawada, S

    2007-01-01

    Proton-pump inhibitors have been reported to influence the human immune system, we therefore evaluated the effect of lansoprazole, a proton-pump inhibitor, on humoral immunity. Patients with gastric ulcer received lansoprazole 30 mg/day for 8 weeks, and serum immunoglobulins were evaluated before and upon completion of the treatment. There were 79 patients with gastric ulcer; 51 were H. pylori-infected and 28 were H. pylori-uninfected. Eighteen patients positive for H. pylori were receiving at least one non-steroidal anti-inflammatory drug, and 12 patients negative for H. pylori received one non-steroidal anti-inflammatory drug. H. pylori-infected patients showed significant increases in serum immunoglobulins G and M 8 weeks after the start of lansoprazole treatment (PLansoprazole elevated serum levels of immunoglobulins G and M in gastric ulcer patients with H. pylori infection, particularly in those receiving non-steroidal anti-inflammatory drugs. Deducing from these observations, lansoprazole might alter the Th1 shift in the immune response induced by H. pylori infection.

  20. Ghrelin and Functional Dyspepsia

    Directory of Open Access Journals (Sweden)

    Takashi Akamizu

    2010-01-01

    Full Text Available The majority of patients with dyspepsia have no identifiable cause of their disease, leading to a diagnosis of functional dyspepsia (FD. While a number of different factors affect gut activity, components of the nervous and endocrine systems are essential for normal gut function. Communication between the brain and gut occurs via direct neural connections or endocrine signaling events. Ghrelin, a peptide produced by the stomach, affects gastric motility/emptying and secretion, suggesting it may play a pathophysiological role in FD. It is also possible that the functional abnormalities in FD may affect ghrelin production in the stomach. Plasma ghrelin levels are reported to be altered in FD, correlating with FD symptom score. Furthermore, some patients with FD suffer from anorexia with body-weight loss. As ghrelin increases gastric emptying and promotes feeding, ghrelin therapy may be a new approach to the treatment of FD.

  1. Ghrelin in the human myometrium

    LENUS (Irish Health Repository)

    O'Brien, Margaret

    2010-05-28

    Abstract Background Ghrelin is a 28-amino acid octanolyated peptide, synthesised primarily in the stomach. It stimulates growth hormone release, food intake and exhibits many other diverse effects. Our group have previously determined that ghrelin inhibited human contractility in vitro. The aim of this study therefore, was to investigate the expression of ghrelin, its receptor, the growth hormone secretagogue receptor type 1 (GHS-R1), ghrelin O-acyltransferase (GOAT) which catalyses ghrelin octanoylation, prohormone convertase 1\\/3 (PC1\\/3) responsible for pro-ghrelin processing, in human myometrium, during pregnancy prior to labour, during labour and in the non-pregnant state. Modulation of ghrelin and ghrelin receptor expression in cultured myometrial cells was also investigated. Methods mRNA and protein were isolated from human myometrium and the myometrial smooth muscle cell line hTERT-HM; and real-time fluorescence RT-PCR, western blotting and fluorescence microscopy performed. The effects of β-Estradiol and bacterial lipopolysaccharide (LPS) on hTERT-HM gene expression were evaluated by western blotting. Results We have reported for the first time the expression and processing of ghrelin, GHS-R1, GOAT and PC1\\/3 expression in human myometrium, and also the down-regulation of ghrelin mRNA and protein expression during labour. Furthermore, GHS-R1 protein expression significantly decreased at labour. Myometrial GOAT expression significantly increased during term non-labouring pregnancy in comparison to both non-pregnant and labouring myometrium. Mature PC1\\/3 protein expression was significantly decreased at term pregnancy and labour in comparison to non-pregnant myometrium. Ghrelin, GHS-R1, GOAT and PC1\\/3 mRNA and protein expression was also detected in the hTERT-HM cells. Ghrelin protein expression decreased upon LPS treatment in these cells while β-Estradiol treatment increased GHS-R1 expression. Conclusions Ghrelin processing occurred in the human

  2. Ghrelin in the human myometrium.

    LENUS (Irish Health Repository)

    O'Brien, Margaret

    2010-01-01

    BACKGROUND: Ghrelin is a 28-amino acid octanolyated peptide, synthesised primarily in the stomach. It stimulates growth hormone release, food intake and exhibits many other diverse effects. Our group have previously determined that ghrelin inhibited human contractility in vitro. The aim of this study therefore, was to investigate the expression of ghrelin, its receptor, the growth hormone secretagogue receptor type 1 (GHS-R1), ghrelin O-acyltransferase (GOAT) which catalyses ghrelin octanoylation, prohormone convertase 1\\/3 (PC1\\/3) responsible for pro-ghrelin processing, in human myometrium, during pregnancy prior to labour, during labour and in the non-pregnant state. Modulation of ghrelin and ghrelin receptor expression in cultured myometrial cells was also investigated. METHODS: mRNA and protein were isolated from human myometrium and the myometrial smooth muscle cell line hTERT-HM; and real-time fluorescence RT-PCR, western blotting and fluorescence microscopy performed. The effects of beta-Estradiol and bacterial lipopolysaccharide (LPS) on hTERT-HM gene expression were evaluated by western blotting. RESULTS: We have reported for the first time the expression and processing of ghrelin, GHS-R1, GOAT and PC1\\/3 expression in human myometrium, and also the down-regulation of ghrelin mRNA and protein expression during labour. Furthermore, GHS-R1 protein expression significantly decreased at labour. Myometrial GOAT expression significantly increased during term non-labouring pregnancy in comparison to both non-pregnant and labouring myometrium. Mature PC1\\/3 protein expression was significantly decreased at term pregnancy and labour in comparison to non-pregnant myometrium. Ghrelin, GHS-R1, GOAT and PC1\\/3 mRNA and protein expression was also detected in the hTERT-HM cells. Ghrelin protein expression decreased upon LPS treatment in these cells while beta-Estradiol treatment increased GHS-R1 expression. CONCLUSIONS: Ghrelin processing occurred in the human

  3. Does helicobacter pylori infection in chronic renal failure increase the risk of gastroduodenal lesions? A prospective study

    Directory of Open Access Journals (Sweden)

    Abdulrahman Ibrahim

    2004-01-01

    Full Text Available Background: Helicobacter pylori (H.pylori plays an important role in gastroduodenal disease. However, there are few data concerning the epidemiology of H.pylori in patients with chronic renal failure and on hemodialysis (HD treatment. Aim of the study: This study is aimed to determine the epidemiology of H.pylori infection in patients with end stage renal disease (ESRD on Hemodialysis (HD. Patients and Methods: Ninety-six patients with dyspeptic complaints were included in the study. They were divided into two groups; group one consisted of 46 patients with ESRD on HD and group two (control of 50 patients without renal disease. All patients were subjected to upper gastrointestinal endoscopies, and gastric biopsies were obtained for histological evidence of H. pylori infection. Results: The mean age of both groups was similar. The prevalence of H.pylori among the two groups was not significantly different (45.7%Vs48%=p>0.05. The prevalence of duodenal ulcers was significantly higher in H.pylori positive than in H.pylori negative ESRD patients (p< 0.05. GERD was significantly lower in H.pylori positive patients in both groups (p< 0.001 and p< 0.01 respectively. Conclusion: This study showed a similar prevalence of H.pylori infection in both groups. H.pylori infection in patients with ESRD is probably associated with increased risk of gastroduodenal lesions

  4. Interruption of Ghrelin Signaling in the PVN Increases High-Fat Diet Intake and Body Weight in Stressed & Non-Stressed C57BL6J Male Mice

    Directory of Open Access Journals (Sweden)

    Zachary Robert Patterson

    2013-09-01

    Full Text Available Chronic social stress has been associated with increased caloric intake and adiposity. These effects have been linked to stress induced changes in the secretion of ghrelin, a hormone that targets a number of brain regions to increase food intake and energy expenditure and promote increased body fat content. One of the brain sites targeted by ghrelin is the hypothalamic paraventricular nucleus (PVN, a region critical for both the regulation of the stress response and the regulation of energy balance. Given these data, we examined the contribution of ghrelin receptors in the PVN to the metabolic and behavioral changes that are seen during chronic social stress in mice. To do this, mice were implanted with cannulae attached to osmotic minipumps and delivering either vehicle or the ghrelin receptor (growth hormone secretagogue receptor antagonist [D-Lys-3]-GHRP-6 (20nmol/day/mouse. Following a week of recovery, half of the animals in each group were exposed to chronic social defeat stress for a period of three weeks whereas the other half were left undisturbed. During this time, all animals were given ad libitum access to standard laboratory chow and presented a high-fat diet for 4 hours during the day. Results showed that the ghrelin receptor antagonism did not decrease stressed induced caloric intake, but paradoxically increased the intake of the high fat diet. This would suggest that ghrelin acts on the PVN to promote the intake of carbohydrate rich diets while decreasing fat intake and blockade of ghrelin receptors in the PVN leads to more consumption of foods that are high in fat.

  5. Increased Outer Membrane Vesicle Formation in a Helicobacter pylori tolB Mutant.

    Science.gov (United States)

    Turner, Lorinda; Praszkier, Judyta; Hutton, Melanie L; Steer, David; Ramm, Georg; Kaparakis-Liaskos, Maria; Ferrero, Richard L

    2015-08-01

    Multiple studies have established the importance of the tol-pal gene cluster in bacterial cell membrane integrity and outer membrane vesicle (OMV) formation in Escherichia coli. In contrast, the functions of Tol-Pal proteins in pathogenic organisms, including those of the Epsilonproteobacteria, remain poorly if at all defined. The aim of this study was to characterize the roles of two key components of the Tol-Pal system, TolB and Pal, in OMV formation in the pathogenic bacterium, Helicobacter pylori. H. pylori ΔtolB, Δpal and ΔtolBpal mutants, as well as complemented strains, were generated and assessed for changes in morphology and OMV production by scanning electron microscopy and enzyme-linked immunoassay (ELISA), respectively. The protein content and pro-inflammatory properties of OMVs were determined by mass spectroscopy and interleukin-8 (IL-8) ELISA on culture supernatants from OMV-stimulated cells, respectively. H. pylori ΔtolB and Δpal bacteria exhibited aberrant cell morphology and/or flagella biosynthesis. Importantly, the disruption of H. pylori tolB but not pal resulted in a significant increase in OMV production. The OMVs from H. pylori ΔtolB and Δpal bacteria harbored many of the major outer membrane and virulence proteins observed in wild-type (WT) OMVs. Interestingly, ΔtolB, Δpal and ΔtolBpal OMVs induced significantly higher levels of IL-8 production by host cells, compared with WT OMVs. This work demonstrates that TolB and Pal are important for membrane integrity in H. pylori. Moreover, it shows how H. pylori tolB-pal genes may be manipulated to develop "hypervesiculating" strains for vaccine purposes. © 2015 John Wiley & Sons Ltd.

  6. Increased gastric IL-1β concentration and iron deficiency parameters in H. pylori infected children.

    Science.gov (United States)

    Queiroz, Dulciene Maria Magalhaes; Rocha, Andreia Maria Camargos; Melo, Fabricio Freire; Rocha, Gifone Aguiar; Teixeira, Kádima Nayara; Carvalho, Simone Diniz; Bittencourt, Paulo Fernando Souto; Castro, Lucia Porto Fonseca; Crabtree, Jean E

    2013-01-01

    Association between H. pylori infection, iron deficiency and iron deficiency anaemia has been described, but the mechanisms involved have not been established. We hypothesized that in H. pylori infected children increased gastric concentrations of IL-1β and/or TNF-α, both potent inhibitors of gastric acid secretion that is essential for iron absorption, are predictors for low blood concentrations of ferritin and haemoglobin, markers of early depletion of iron stores and anaemia, respectively. We evaluated 125 children undergoing endoscopy to clarify the origin of gastrointestinal symptoms. Gastric specimens were obtained for H. pylori status and cytokine evaluation and blood samples for determination of iron deficiency/iron deficiency anaemia parameters and IL1 cluster and TNFA polymorphisms that are associated with increased cytokine secretions. Higher IL-1β and TNF-α gastric concentrations were observed in H. pylori-positive (n = 47) than in -negative (n = 78) children. Multiple linear regression models revealed gastric IL-1β, but not TNF-α, as a significant predictor of low ferritin and haemoglobin concentrations; results were reproduced in young children in whom IL1RN polymorphic genotypes associated with higher gastric IL-1β expression and lower blood ferritin and haemoglobin concentrations. In conclusion, high gastric levels of IL-1β can be the link between H. pylori infection and iron deficiency/iron deficiency anaemia in childhood.

  7. Increased peptide YY blood concentrations, not decreased acyl-ghrelin, are associated with reduced hunger and food intake in healthy older women: Preliminary evidence.

    Science.gov (United States)

    Hickson, Mary; Moss, Charlotte; Dhillo, Waljit S; Bottin, Jeanne; Frost, Gary

    2016-10-01

    With ageing there is frequently a loss of appetite, termed anorexia of ageing, which can result in under-nutrition. We do not know how appetite control alters with ageing. The objective of this study was to investigate whether differences in the release of, and response to, gastrointestinal appetite hormones is altered in young compared to old healthy volunteers. We hypothesised that an increase in PYY and GLP-1 or a decrease ghrelin may result in a decreased appetite. A comparative experimental design, using a cross-sectional sample of ages from a healthy population, matched for sex and BMI was used. The study compared total ghrelin, acyl-ghrelin, PYY, GLP-1 and subjective appetite responses to ingestion of a standardised 2781kj (660 kcal) test meal. 31 female volunteers aged between 21 and 92yrs took part. Multiple linear regression showed that both age and sex had an independent effect on energy intake. Subjective appetite scores showed that hunger, pleasantness to eat, and prospective food intake were significantly lower in the older age groups. PYY incremental area under the curve (IAUC) was greater in the oldest old compared to younger ages f(3,27) = 2.9, p = 0.05. No differences in GLP-1, ghrelin or acyl-ghrelin were observed in the older compared to younger age groups. Our data suggest that there may be increases in postprandial PYY(3-36) levels in female octogenarians, potentially resulting in reduced appetite. There does not appear to be any change in ghrelin or acyl-ghrelin concentrations with ageing.

  8. Acetylcholine regulates ghrelin secretion in humans

    NARCIS (Netherlands)

    F. Broglio (Fabio); E. Ghigo (Ezio); C. Gottero; F. Prodam (Flavia); S. Destefanis; A. Benso; C. Gauna (Carlotta); L.J. Hofland (Leo); E. Arvat; A-J. van der Lely (Aart-Jan); P.M. van Koetsveld (Peter)

    2004-01-01

    textabstractGhrelin secretion has been reportedly increased by fasting and energy restriction but decreased by food intake, glucose, insulin, and somatostatin. However, its regulation is still far from clarified. The cholinergic system mediates some ghrelin actions, e.g.

  9. [Ghrelin: beyond hunger regulation].

    Science.gov (United States)

    Milke García, Maria del Pilar

    2005-01-01

    Man ingests food to mitigate hunger (mediated by physiological and biochemical signals), satisfy appetite (subjective sensation) and because of psychosocial reasons. Satiation biomarkers (stop feeding) are gastric distention and hormones (CCK, GLP-1) and satiety biomarkers (induce feeding) are food-induced thermogenesis, body temperature, glycaemia and also hormones (insulin, leptin and ghrelin). Oxidative metabolism/body composition, tryptophan/serotonin and proinflammatory cytokines are also implicated on hunger physiology. At the present time, ghrelin is the only known circulating orexigenic with potential on hunger/body weight regulation. It is a neuropeptide (endogenous ligand for the GH secretagogue) recently isolated from the oxyntic mucosa and synthesized mainly in the stomach. Its blood concentration depends on diet, hyperglucemia and adiposity/leptin. It is secreted 1-2 hours preprandially and its concentration decreases drastically during the postprandium. Ghrelin acts on the lateral hypothalamus and theoretically inhibits proinflammatory cytokine secretion and antagonizes leptin. Ghrelin physiologically increases food intake and stimulates adipogenesis, gastrointestinal motility and gastric acid secretion, and has other hormonal and cardiovascular functions. Ghrelin blood concentration is reduced in massive obesity, non-alcoholic steatohepatitis, polycystic ovary syndrome, acromegaly, hypogonadism, ageing, short bowel syndrome and rheumatoid arthritis; and increased in primary or secondary anorexia, starvation, chronic liver disease and celiac disease. Cerebral and peritoneal ghrelin administration (rats) and systemic administration (rats and healthy volunteers, cancer patients or patients on peritoneal dialysis) promotes food consumption and increases adiposity, of utmost importance in the treatment of patients with anorexia.

  10. Increased acylated plasma ghrelin, but improved lipid profiles 24-h after consumption of carob pulp preparation rich in dietary fibre and polyphenols.

    Science.gov (United States)

    Gruendel, Sindy; Garcia, Ada L; Otto, Baerbel; Wagner, Karen; Bidlingmaier, Martin; Burget, Lukas; Weickert, Martin O; Dongowski, Gerhard; Speth, Maria; Katz, Norbert; Koebnick, Corinna

    2007-12-01

    We have recently shown that a polyphenol-rich insoluble dietary fibre preparation from carob pulp (Ceratonia siliqua L; carob fibre) decreased postprandial acylated ghrelin, TAG and NEFA during an acute liquid meal challenge test. However, delayed effects of carob fibre consumption are unknown. Therefore, a randomized controlled crossover study in nineteen healthy volunteers consuming foods with or without 50 g carob fibre was conducted. On the subsequent day (day 2), glucose, TAG, total and acylated ghrelin as well as insulin, NEFA and leptin were assessed at baseline and at timed intervals for 300 min after ingestion of standardized bread. Consumption of carob fibre-enriched foods did not affect fasting concentrations of glucose, TAG, total ghrelin, NEFA, insulin and leptin. Fasting acylated ghrelin was increased on the day subsequent to carob fibre consumption compared with control (P = 0.046). After consumption of the standard bread on day 2, glucose response (P = 0.029) was increased, and TAG (P = 0.033) and NEFA (P carob fibre consumption the previous day. In conclusion, an increase in total and acylated plasma ghrelin accompanied by enhanced lipid metabolism after carob fibre consumption suggests higher lipid utilization and suppressed lipolysis on the day subsequent to carob fibre consumption. However, elevated glucose levels after carob fibre consumption need to be addressed in future studies.

  11. Ghrelin and gastric acid secretion

    OpenAIRE

    Yakabi, Koji; Kawashima, Junichi; Kato, Shingo

    2008-01-01

    Ghrelin, a novel growth hormone-releasing peptide, was originally isolated from rat and human stomach. Ghrelin has been known to increase the secretion of growth hormone (GH), food intake, and body weight gain when administered peripherally or centrally. Ghrelin is also known to stimulate the gastric motility and the secretion of gastric acid. In the previous studies, the action of ghrelin on acid secretion was shown to be as strong as that of histamine and gastrin in in-vivo experiment. In t...

  12. The mechanism of anorexia in children with Helicobacter pylori infection%幽门螺杆菌感染儿童厌食机制研究

    Institute of Scientific and Technical Information of China (English)

    蒋丽蓉; 邓朝晖; 张斌; 储波; 徐亚珍

    2011-01-01

    Objective To study the expression of Ghrelin and the virulence genes of Helicobacter pylori ( H. Pylori) in the mechanism of anorexia in children with H. Pylori infection. Methods Sixty children with H. Pylori infection were recruited and divided into two groups based on the presence of anorexia, anorexia group ( n = 30 ) and non-anorexia group (n = 30 ). The expression of Ghrelin Mrna in gastric mucosa was detected by RT-PCR and compared. The cagA/vacA genotyping of H. Pylori was isolated and tested by PCR. Results The expression of Ghrelin Mrna in gastric mucosa was significantly decreased in anorexia group than in non-anorexia group (P < 0.01 ). In anorexia group, the expression of Ghrelin Mrna after H. Pylori eradication therapy was significantly increased than before (P < 0.05 ). Meanwhile, the apptite was improved and the weight gain was significantly increased in anorexia group. The strains of H. Pylori isolated were type I in all children. The positive rate of cagA ml in anorexia group was higher than that in non-anorexia group. More sl/ml genotypes was found in anorexia group. Conclusions The expression of Ghrelin Mrna was decreased in anorexia children with H. Pylori infection and increased after H. Pylori eradication therapy. H. Pylori may cause anorexia through influencing the Ghrelin secretion. Different genotypes (vacA sl/ml ) may be the key factor on the Ghrelin secretion for anorexia children with H. Pylori infection.%目的 探讨Ghrelin表达以及不同幽门螺杆菌(H.Pylori)毒力基因型在H.Pylori感染患儿厌食发病机制中的作用.方法 H.Pylori感染患儿60例,根据临床表现分为厌食(n = 30例)和非厌食(n = 30例)组.应用RT-PCR方法检测胃黏膜Ghrelin mRNA表达水平,比较两组患儿以及厌食患儿在H.Pylori根治前后的差异.同时采用PCR方法检测所有患儿的H.Pylori毒力cagA/vacA基因并分型.结果 H.Pylori感染厌食患儿胃黏膜Ghrelin mRNA表达低于非厌食患儿,两

  13. Thermogenic characterization of ghrelin receptor null mice

    Science.gov (United States)

    Ghrelin is the only known circulating orexigenic hormone that increases food intake and promotes adiposity, and these physiological functions of ghrelin are mediated through its receptor growth hormone secretagogue receptor (GHS-R). Ghrelin/GHS-R signaling plays a crucial role in energy homeostasis....

  14. Ghrelin: new molecular pathways modulating appetite and adiposity.

    Science.gov (United States)

    Nogueiras, Ruben; Williams, Lynda M; Dieguez, Carlos

    2010-10-01

    Ghrelin is a unique endogenous peptidic hormone regulating both hunger and adiposity. Many of the actions of ghrelin are modulated specifically by the central nervous system. A number of molecular events triggered via the activation of the ghrelin receptor (GHS-R1a), leading to increased levels of neuropeptide Y (NPY) and agoutirelated peptide (AgRP) and ultimately responsible for the orexigenic effect of ghrelin have been characterized. Moreover, the discovery of ghrelin O-acyltransferase (GOAT), the enzyme responsible for the octanoylation of ghrelin, provides a mechanism allowing specific targeting of the ghrelin/GHS-R1a system without affecting the role of des-acyl-ghrelin in other pathways involved in the regulation of energy balance. This review aims to summarize novel roles of ghrelin in energy balance, focusing particularly on both the newly identified neuronal pathways mediating the effects of ghrelin and on peripheral mechanisms leading to increased adiposity. Copyright © 2010 S. Karger AG, Basel.

  15. Psychological Stress Increases Risk for Peptic Ulcer, Regardless of Helicobacter pylori Infection or Use of Nonsteroidal Anti-inflammatory Drugs

    DEFF Research Database (Denmark)

    Levenstein, Susan; Rosenstock, Steffen; Jacobsen, Rikke Kart

    2015-01-01

    antibodies against Helicobacter pylori in stored sera, alcohol consumption, or sleep duration but lower after adjusting for socioeconomic status (1.17; 95% CI, 1.07-1.29; P drugs, and lack of exercise (1.......11; 95% CI, 1.01-1.23; P = .04). The risk for ulcer related to stress was similar among subjects who were H pylori seropositive, those who were H pylori seronegative, and those exposed to neither H pylori nor nonsteroidal anti-inflammatory drugs. On multivariable analysis, stress, socioeconomic status......, smoking, H pylori infection, and use of nonsteroidal anti-inflammatory drugs were independent predictors of ulcer. CONCLUSIONS: In a prospective study of a population-based Danish cohort, psychological stress increased the incidence of peptic ulcer, in part by influencing health risk behaviors. Stress had...

  16. Downregulated regulatory T cell function is associated with increased peptic ulcer in Helicobacter pylori-infection.

    Science.gov (United States)

    Bagheri, Nader; Shirzad, Hedayatollah; Elahi, Shokrollah; Azadegan-Dehkordi, Fatemeh; Rahimian, Ghorbanali; Shafigh, Mohammedhadi; Rashidii, Reza; Sarafnejad, Abdulfatah; Rafieian-Kopaei, Mahmoud; Faridani, Rana; Tahmasbi, Kamran; Kheiri, Soleiman; Razavi, Alireza

    2017-09-01

    Helicobacter pylori (H. pylori) chronically colonizes gastric/duodenal mucosa and induces gastroduodenal disease such as gastritis and peptic ulcer and induces vigorous innate and specific immune responses; however, the infection is not removed, a state of chronic active gastritis persists for life if untreated. The objective of this study was to determine the number of regulatory T cells (Tregs) in gastric mucosa of patients with gastritis and peptic ulcer and determined the relationship between main virulence factor of H. pylori and Tregs. A total of 89 patients with gastritis, 63 patients with peptic ulcer and 40 healthy, H. pylori-negative subjects were enrolled in this study. Expression of CD4 and Foxp3 was determined by immunohistochemistry. Antrum biopsy was obtained for detection of H. pylori, bacterial virulence factors and histopathological assessments. TGF-β1, IL-10 and FOXP3 expressions were determined by real-time polymerase chain reaction (qPCR). The numbers of CD4(+) and Foxp3(+) T cells as well as the expression of IL-10, TGF-β1, FOXP3, INF-γ and IL-17A in infected patients were significantly higher than the ones in uninfected patients. Also, the number of CD4(+) T cells was independent on the vacuolating cytotoxin A (vacA) and outer inflammatory protein A (oipA), but it was positively correlated with cytotoxin-associated gene A (cagA). Instead, the number of Foxp3(+) T cells was dependent on the vacA and oipA, but it was independent on cagA. The number of Foxp3(+) T cells and the expression of IL-10, TGF-β1 and FOXP3 in infected patients with gastritis were significantly higher than the ones in infected patients with peptic ulcer. Moreover, the number of CD4(+) T cells and the expression of IL-17A and INF-γ was the lowest in the gastritis patients, however, increased progressively in the peptic ulcer patients. Additionally, the numbers of CD4(+) and Foxp3(+) T cells as well as the expression of IL-10, TGF-β1, FOXP3 and INF-γ were

  17. Dietary Caprylic Acid (C8:0) Does Not Increase Plasma Acylated Ghrelin but Decreases Plasma Unacylated Ghrelin in the Rat

    OpenAIRE

    Fanny Lemarié; Erwan Beauchamp; Stéphanie Dayot; Cécile Duby; Philippe Legrand; Vincent Rioux

    2015-01-01

    International audience; Focusing on the caprylic acid (C8:0), this study aimed at investigating the discrepancy between the formerly described beneficial effects of dietary medium chain fatty acids on body weight loss and the C8:0 newly reported effect on food intake via ghrelin octanoylation. During 6 weeks, Sprague-Dawley male rats were fed with three dietary C8:0 levels (0, 8 and 21% of fatty acids) in three experimental conditions (moderate fat, caloric restriction and high fat). A specif...

  18. Helicobacter pylori infection may increase the risk of progression of chronic hepatitis B disease among the Chinese population: a meta-analysis

    OpenAIRE

    Juan Wang; Ruo-Chan Chen; Yi-Xiang Zheng; Shu-Shan Zhao; Ning Li; Rong-Rong Zhou; Yan Huang; Ze-Bing Huang; Xue-Gong Fan

    2016-01-01

    Objectives: Helicobacter pylori is a bacterium that infects over 50% of the human population worldwide. An increasing number of studies have demonstrated that H. pylori may cause liver diseases, and the underlying relationship between H. pylori infection and chronic hepatitis B has attracted much attention. This study aimed to examine the association between H. pylori infection and the progression of chronic hepatitis B in the Chinese population. Methods: A search was performed of the PubM...

  19. Carbon dioxide in carbonated beverages induces ghrelin release and increased food consumption in male rats: Implications on the onset of obesity.

    Science.gov (United States)

    Eweis, Dureen Samandar; Abed, Fida; Stiban, Johnny

    2017-02-19

    The dangerous health risks associated with obesity makes it a very serious public health issue. Numerous studies verified a correlation between the increase in obesity and the parallel increase in soft drink consumption among world populations. The effects of one main component in soft drinks namely the carbon dioxide gas has not been studied thoroughly in any previous research. Male rats were subjected to different categories of drinks and evaluated for over a year. Stomach ex vivo experiments were undertaken to evaluate the amount of ghrelin upon different beverage treatments. Moreover, 20 male students were tested for their ghrelin levels after ingestion of different beverages. Here, we show that rats consuming gaseous beverages over a period of around 1 year gain weight at a faster rate than controls on regular degassed carbonated beverage or tap water. This is due to elevated levels of the hunger hormone ghrelin and thus greater food intake in rats drinking carbonated drinks compared to control rats. Moreover, an increase in liver lipid accumulation of rats treated with gaseous drinks is shown opposed to control rats treated with degassed beverage or tap water. In a parallel study, the levels of ghrelin hormone were increased in 20 healthy human males upon drinking carbonated beverages compared to controls. These results implicate a major role for carbon dioxide gas in soft drinks in inducing weight gain and the onset of obesity via ghrelin release and stimulation of the hunger response in male mammals. Copyright © 2017 Asia Oceania Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.

  20. Metabolic and Cardiovascular Effects of Ghrelin

    Directory of Open Access Journals (Sweden)

    Manfredi Tesauro

    2010-01-01

    Ghrelin receptors have been detected in the hypothalamus and the pituitary, but also in the cardiovascular system, where ghrelin exerts beneficial hemodynamic activities. Ghrelin administration acutely improves endothelial dysfunction by increasing nitric oxide bioavailability and normalizes the altered balance between endothelin-1 and nitric oxide within the vasculature of patients with metabolic syndrome. Other cardiovascular effects of ghrelin include improvement of left ventricular contractility and cardiac output, as well as reduction of arterial pressure and systemic vascular resistance. In addition, antinflammatory and antiapoptotic actions of ghrelin have been reported both in vivo and in vitro. This review summarizes the most recent findings on the metabolic and cardiovascular effects of ghrelin through GH-dependent and -independent mechanisms and the possible role of ghrelin as a therapeutic molecule for treating cardiovascular diseases.

  1. Anticipatory and consummatory effects of (hedonic) chocolate intake are associated with increased circulating levels of the orexigenic peptide ghrelin and endocannabinoids in obese adults

    Science.gov (United States)

    Rigamonti, Antonello E.; Piscitelli, Fabiana; Aveta, Teresa; Agosti, Fiorenza; De Col, Alessandra; Bini, Silvia; Cella, Silvano G.; Di Marzo, Vincenzo; Sartorio, Alessandro

    2015-01-01

    Background Hedonic hunger refers to consumption of food just for pleasure and not to maintain energy homeostasis. Recently, consumption of food for pleasure was reported to be associated with increased circulating levels of both the orexigenic peptide ghrelin and the endocannabinoid 2-arachidonoyl-glycerol (2-AG) in normal-weight subjects. To date, the effects of hedonic hunger, and in particular of chocolate craving, on these mediators in obese subjects are still unknown. Methods To explore the role of some gastrointestinal orexigenic and anorexigenic peptides and endocannabinoids (and some related congeners) in chocolate consumption, we measured changes in circulating levels of ghrelin, glucagon-like peptide 1 (GLP-1), peptide YY (PYY), anandamide (AEA), 2-AG, palmitoylethanolamide (PEA), and oleoylethanolamide (OEA) in 10 satiated severely obese subjects after consumption of chocolate and, on a separate day, of a non-palatable isocaloric food with the same bromatologic composition. Evaluation of hunger and satiety was also performed by visual analogic scale. Results The anticipatory phase and the consumption of food for pleasure were associated with increased circulating levels of ghrelin, AEA, 2-AG, and OEA. In contrast, the levels of GLP-1, PYY, and PEA did not differ before and after the exposure/ingestion of either chocolate or non-palatable foods. Hunger and satiety were higher and lower, respectively, in the hedonic session than in the non-palatable one. Conclusions When motivation to eat is generated by exposure to, and consumption of, chocolate a peripheral activation of specific endogenous rewarding chemical signals, including ghrelin, AEA, and 2-AG, is observed in obese subjects. Although preliminary, these findings predict the effectiveness of ghrelin and endocannabinoid antagonists in the treatment of obesity. PMID:26546790

  2. Anticipatory and consummatory effects of (hedonic chocolate intake are associated with increased circulating levels of the orexigenic peptide ghrelin and endocannabinoids in obese adults

    Directory of Open Access Journals (Sweden)

    Antonello E. Rigamonti

    2015-11-01

    Full Text Available Background: Hedonic hunger refers to consumption of food just for pleasure and not to maintain energy homeostasis. Recently, consumption of food for pleasure was reported to be associated with increased circulating levels of both the orexigenic peptide ghrelin and the endocannabinoid 2-arachidonoyl-glycerol (2-AG in normal-weight subjects. To date, the effects of hedonic hunger, and in particular of chocolate craving, on these mediators in obese subjects are still unknown. Methods: To explore the role of some gastrointestinal orexigenic and anorexigenic peptides and endocannabinoids (and some related congeners in chocolate consumption, we measured changes in circulating levels of ghrelin, glucagon-like peptide 1 (GLP-1, peptide YY (PYY, anandamide (AEA, 2-AG, palmitoylethanolamide (PEA, and oleoylethanolamide (OEA in 10 satiated severely obese subjects after consumption of chocolate and, on a separate day, of a non-palatable isocaloric food with the same bromatologic composition. Evaluation of hunger and satiety was also performed by visual analogic scale. Results: The anticipatory phase and the consumption of food for pleasure were associated with increased circulating levels of ghrelin, AEA, 2-AG, and OEA. In contrast, the levels of GLP-1, PYY, and PEA did not differ before and after the exposure/ingestion of either chocolate or non-palatable foods. Hunger and satiety were higher and lower, respectively, in the hedonic session than in the non-palatable one. Conclusions: When motivation to eat is generated by exposure to, and consumption of, chocolate a peripheral activation of specific endogenous rewarding chemical signals, including ghrelin, AEA, and 2-AG, is observed in obese subjects. Although preliminary, these findings predict the effectiveness of ghrelin and endocannabinoid antagonists in the treatment of obesity.

  3. Oxyntomodulin increases the concentrations of insulin and glucose in plasma but does not affect ghrelin secretion in Holstein cattle under normal physiological conditions.

    Science.gov (United States)

    ThanThan, S; Zhao, H; Yannaing, S; Ishikawa, T; Kuwayama, H

    2010-10-01

    Ghrelin, the natural ligand of the growth hormone secretagogue receptor (GHS-R1a), has been shown to stimulate growth hormone (GH) secretion. Regulation of ghrelin secretion in ruminants is not well studied. We investigated the effects of oxyntomodulin (OXM) and secretin on the secretions of ghrelin, insulin, glucagon, glucose, and nonesterified fatty acids (NEFA) in pre-ruminants (5 wk old) and ruminants (10 wk old) under normal physiological (feeding) conditions. Eight male Holstein calves (pre-ruminants: 52 +/- 1 kg body weight [BW]; and ruminants: 85 +/- 1 kg BW) were injected intravenously with 30 microg of OXM/kg BW, 50 microg of secretin/kg BW, and vehicle (0.1% bovine serum albumin [BSA] in saline as a control) in random order. Blood samples were collected, and plasma hormones and metabolites were analyzed using a double-antibody radioimmunoassay system and commercially available kits, respectively. We found that OXM increased the concentrations of insulin and glucose but did not affect the concentrations of ghrelin in both pre-ruminants and ruminants and that there was no effect of secretin on the concentrations of ghrelin, insulin, and glucose in these calves. We also investigated the dose-response effects of OXM on the secretion of insulin and glucose in 8 Holstein steers (401 +/- 1 d old, 398 +/- 10 kg BW). We found that OXM increased the concentrations of insulin and glucose even at physiological plasma concentrations, with a minimum effective dose of 0.4 microg/kg for the promotion of glucose secretion and 2 microg/kg for the stimulation of insulin secretion. These findings suggest that OXM takes part in glucose metabolism in ruminants.

  4. Ghrelin family of peptides and gut motility.

    Science.gov (United States)

    Asakawa, Akihiro; Ataka, Koji; Fujino, Kazunori; Chen, Chih-Yen; Kato, Ikuo; Fujimiya, Mineko; Inui, Akio

    2011-04-01

    Acyl ghrelin, des-acyl ghrelin, and obestatin are three peptides isolated from the gastrointestinal tract and encoded by the same preproghrelin gene. Three ghrelin gene products participate in modulating appetite, adipogenesis, glucose metabolism, cell proliferation, immune, sleep, memory, anxiety, cognition, and stress. We have investigated the effects of ghrelin family of peptides on fed and fasted motor activities in the stomach and duodenum of freely moving conscious rats by manometric method. Intracerebroventricular (ICV) and intravenous (IV) administration of acyl ghrelin induced fasted motor activity in the duodenum in fed rats. ICV and IV administration of des-acyl ghrelin disrupted fasted motor activity in the antrum. Changes in gastric motility induced by IV administration of des-acyl ghrelin were antagonized by ICV administration of a corticotropin-releasing factor (CRF) 2 receptor antagonist. IV administration of obestatin decreased the percentage motor index in the antrum and prolonged the time taken to return to fasted motility in the duodenum in fed rats. ICV administration of CRF 1 and 2 receptor antagonists prevented the effects of obestatin on gastroduodenal motility. Ghrelin gene products regulate feeding-associated gastroduodenal motility. Stomach may regulate various functions including gastrointestinal motility via acyl ghrelin, des-acyl ghrelin and obestatin as an endocrine organ. Increasing knowledge of the effects of ghrelin family of peptides on gastrointestinal motility could lead to innovative new therapies for functional gastrointestinal disorders.

  5. 血清Ghrelin和瘦素水平与幽门螺杆菌感染的关系研究%Relation of Helicobacter Pylori Infection with Serum Ghrelin and Leptin Levels

    Institute of Scientific and Technical Information of China (English)

    郁海静; 张静; 丁士刚; 杨雪玲; 刘琳娜; 王晔

    2011-01-01

    与否对血清Ghrelin及瘦素水平没有影响,性别对血清Ghrelin水平可能有影响,BMI对血清Ghrelin及瘦素水平可能有影响.%Objective To investigate the relationship of serum Ghrelin and leptin levels with Helicobacter pylori ( Hp )infection, and further identify its clinical significance. Methods Totally 116 patients who underwent gastroscopy from April to July 2009 were recruited. Blood serum Ghrelin and leptin levels and serum immunoglobulin G antibodies against Hp were assessed by ELISA method. All patients underwent gastroscopy with biopsies from gastric antrum and gastric body in order to judge Hp infection status with Warthin - Starry staining. Results The serum Ghrelin level and leptin level of Hp positivity patients were respectively lower than those of Hp negativity patients ( 291.03 pg/ml vs 374.77 pg/ml and 4.34 ng/ml vs 4.37 ng/ml, respectively ), hut with no statistically significant difference ( P = 0.288, 0.550 ). The Chrelin level of male patients was significantly lower than that of female patients ( 232.28 pg/ml vs. 403.09 pg/ml ) ( P = 0.000 ) ; and the leptin level of male patients was also lower than that of female patients ( 4.24 ng/ml vs. 4.46 ng/ml ), but with no statistical significance ( P =0.671 ). No statistically significant difference was found in Ghrelin level between male patients with Hp positivity and with Hp negativity ( 243.87 pg/ml vs. 205.67 pg/ml, P =0.950 ), so was in leptin level ( 4.16 ng/ml vs. 4.42 ng/ml, P =0.297 ). No statistically significant difference was found in both Ghrelin level and leptin level between female patients with Hp positivity and with Hp negativity ( 342.12 pg/ml vs. 494.54 pg/ml, P =0.330; 4.54 ng/ml vs. 4.34 ng/ml, P =0.856. respectively ). There were significant difference in Ghrelin and leptin levels between patients whose body mass index ( BMI ) < 24.0 kg/m2 and BMI≥24.0 kg/m2 ( 362.28 pg/ml vs. 238.40 pg/ml, P=0.003 ; 3.83 ng/ml vs. 5.39 ng/ml, P = 0.000, respectively

  6. Increased plasma malondialdehyde and ffuctosamine in anemic H pylori infected patients: Effect of treatment

    Institute of Scientific and Technical Information of China (English)

    G Vijayan; RC Sundaram; Zachariah Bobby; Abdoul Hamide; N Selvaraj; N Rattina Dasse

    2007-01-01

    AIM: To unravel the possible association of malondialdehyde (MDA) and fructosamine in anemic H pylori infected patients and to observe the alteration in MDA and fructosamine levels in these patients after treatment for one month.METHODS: Fructosamine, MDA and glucose were estimated in 22 anemic H pylori infected patients and 16 healthy controls. Hematological parameters were also evaluated in both the groups using Sysmex-K-100 automated cell counter. The H pylori infected patients were randomly divided into two groups. H pylori infected patients in Group Ⅰ received both iron supplementation and anti-H pylori therapy, while patients in Group Ⅱ received only iron supplementation. All the biochemical and hematological parameters were estimated after one month of treatment.RESULTS: In anemic H pylori infected patients, while MDA (5.41 ± 2.16 vs 2.26 ± 0.50; P < 0.05) and fructosamine (2.64 ± 0.93 vs 1.60 ± 0.35; P < 0.05)were significantly increased, iron (32.72 ± 14.93 vs 110.25 ± 26.58; P < 0.05), hemoglobin (6.9 ± 2.6 vs 12.66 ± 0.74; P < 0.05) and ferritin (28.82 ± 16.27vs 140.43 ± 30.72; P < 0.05) levels were significantly decreased compared with the controls. With partial correlation analysis, fructosamine was found to have a significant positive correlation with MDA. In Group Ⅰ,while MDA level decreased significantly (3.11 ± 1.73 vs 5.50 ± 2.46; P < 0.05), there was a significant increase in iron (84.09 ± 29.51 vs 36.09 ± 17.81; P < 0.05),hemoglobin (10.40 ± 1.11 vs 7.42 ± 1.90; P < 0.05)and ferritin (116.91 ± 63.34 vs 30.46 ± 17.81; P < 0.05)levels after one month. There was no significant change in the levels of fructosamine in group Ⅰ after treatment.Similarly, no significant alterations were noted in the levels of MDA, fructosamine, hemoglobin or ferritin in Group Ⅱ patients after one month of treatment.CONCLUSION: An increased level of fructosamine and MDA was found in anemic H pylori infected patients

  7. Increased plasma malondialdehyde and fructosamine in anemic H pylori infected patients: Effect of treatment

    Science.gov (United States)

    Vijayan, G; Sundaram, RC; Bobby, Zachariah; Hamide, Abdoul; Selvaraj, N; Rattina Dasse, N

    2007-01-01

    AIM: To unravel the possible association of malon-dialdehyde (MDA) and fructosamine in anemic H pylori infected patients and to observe the alteration in MDA and fructosamine levels in these patients after treatment for one month. METHODS: Fructosamine, MDA and glucose were estimated in 22 anemic H pylori infected patients and 16 healthy controls. Hematological parameters were also evaluated in both the groups using Sysmex-K-100 automated cell counter. The H pylori infected patients were randomly divided into two groups. H pylori infected patients in GroupIreceived both iron supplementation and anti-H pylori therapy, while patients in Group II received only iron supplementation. All the biochemical and hematological parameters were estimated after one month of treatment. RESULTS: In anemic H pylori infected patients, while MDA (5.41 ± 2.16 vs 2.26 ± 0.50; P < 0.05) and fructosamine (2.64 ± 0.93 vs 1.60 ± 0.35; P < 0.05) were significantly increased, iron (32.72 ± 14.93 vs 110.25 ± 26.58; P < 0.05), hemoglobin (6.9 ± 2.6 vs 12.66 ± 0.74; P < 0.05) and ferritin (28.82 ± 16.27 vs 140.43 ± 30.72; P < 0.05) levels were significantly decreased compared with the controls. With partial correlation analysis, fructosamine was found to have a significant positive correlation with MDA. In GroupI, while MDA level decreased significantly (3.11 ± 1.73 vs 5.50 ± 2.46; P < 0.05), there was a significant increase in iron (84.09 ± 29.51 vs 36.09 ± 17.81; P < 0.05), hemoglobin (10.40 ± 1.11 vs 7.42 ± 1.90; P < 0.05) and ferritin (116.91 ± 63.34 vs 30.46 ± 17.81; P < 0.05) levels after one month. There was no significant change in the levels of fructosamine in groupIafter treatment. Similarly, no significant alterations were noted in the levels of MDA, fructosamine, hemoglobin or ferritin in Group II patients after one month of treatment. CONCLUSION: An increased level of fructosamine and MDA was found in anemic H pylori infected patients. Present data supports the

  8. Increased Cell Proliferation in Chronic Helicobacter pylori Positive Gastritis and Gastric Carcinoma – Correlation between Immuno-Histochemistry and Tv Image Cytometry

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    Erika Szaleczky

    2000-01-01

    Full Text Available Backgound: Epithelial cell proliferation activity has been reported both to be unaltered and increased in Helicobacter pylori (H. pylori associated chronic gastritis. The proliferation rate decreased following H. pylori eradication, but results are controversial whether this change is dependent on the success of eradication. We compared the cell proliferation activity of H. pylori positive and negative gastric epithelial biopsies in chronic gastritis with and without intestinal metaplasia (IM and gastric cancer by the expression of proliferation cell nuclear antigen (PCNA and Tv image cytometry, and assessed the effect of H. pylori eradication on the cell proliferation rate in the gastric epithelium.

  9. Dietary unsaturated fatty acids increase plasma glucagon-like peptide-1 and cholecystokinin and may decrease premeal ghrelin in lactating dairy cows.

    Science.gov (United States)

    Bradford, B J; Harvatine, K J; Allen, M S

    2008-04-01

    Previous reports have indicated that dietary unsaturated fat can decrease energy intake of lactating dairy cattle. However, the mechanism for this response is unclear. To evaluate the potential role of gut peptides, periprandial concentrations of cholecystokinin (CCK), glucagon-like peptide 1 (GLP-1), and ghrelin were measured. From a replicated 4 x 4 Latin square experiment, 4 cows from a single square were selected for analysis of responses to 3 treatments: a control diet (5.5% total fatty acids, 65% unsaturated), a diet with added saturated fat (SAT, 8.3% fatty acids, 47% unsaturated), and a diet with added unsaturated fat (UNS, 7.8% fatty acids, 63% unsaturated). The SAT treatment increased duodenal flow of saturated fatty acids compared with UNS and control and, despite the fact that ruminal biohydrogenation altered fatty acid profiles of digesta, UNS increased duodenal flow of unsaturated fatty acids compared with SAT and control. Blood samples were collected at 8-min intervals through the first 2 meals of the day and analyzed by commercial radioimmunoassays. The UNS treatment increased plasma CCK concentration relative to SAT and control, and increased plasma GLP-1 concentration compared with control. Furthermore, fat treatments tended to suppress the prandial ghrelin surge that was evident for control. Suppression of feed intake by unsaturated fats is likely mediated in part by increased secretion of CCK and GLP-1, and dietary fat may also inhibit ghrelin release before conditioned meals.

  10. Plasma leptin and ghrelin concentrations in patients with Crohn's disease

    Institute of Scientific and Technical Information of China (English)

    Yoshito Nishi; Hajime Isomoto; Hiroaki Ueno; Ken Ohnita; Chun Yang Wen; Fuminao Takeshima; Ryosuke Mishima; Masamitsu Nakazato; Shigeru Kohno

    2005-01-01

    AIM: To determine the concentrations of leptin and ghrelin, which have opposite effects on appetite,energy expenditure, and weight control, in the plasma of patients with Crohn's disease (CD), which is often associated with weight loss and malnutrition.METHODS: Plasma leptin and ghrelin concentrations were determined in 28 outpatients with CD by radioimmunoassay. Age- and sex-matched controls with and without Helicobacter pylori(H pylori) infection (28for each) were enrolled in the study. Circulating levels of these hormones were assessed with respect to CD activity, disease localization and medical treatment.RESULTS: There were no significant differences in ghrelin levels between CD patients and H pylorinegative controls. However, circulating ghrelin levels were significantly lower in H pylori-infected subjects than in CD patients and uninfected controls. Plasma leptin levels were comparable among the groups. Localization and medication profile had no significant impact on circulating ghrelin and leptin levels.CONCLUSION: Apart from H pyloriinfection, CD itself has no significant influence on circulating ghrelin and leptin levels in the outpatients who were mostly in inactive state.

  11. Dietary Mannoheptulose Increases Fasting Serum Glucagon Like Peptide-1 and Post-Prandial Serum Ghrelin Concentrations in Adult Beagle Dogs.

    Science.gov (United States)

    McKnight, Leslie L; Eyre, Ryan; Gooding, Margaret A; Davenport, Gary M; Shoveller, Anna Kate

    2015-06-16

    There is a growing interest in the use of nutraceuticals for weight management in companion animals. The purpose of this study was to determine the effects of mannoheptulose (MH), a sugar in avocados that inhibits glycolysis, on energy metabolism in adult Beagle dogs. The study was a double-blind, randomized controlled trial where dogs were allocated to a control (CON, n = 10, 10.1 ± 0.4 kg) or MH containing diet (168 mg/kg, n = 10, 10.3 ± 0.4 kg). Blood was collected after an overnight fast and 1 h post-feeding (week 12) to determine serum satiety related hormones and biochemistry. Resting and post-prandial energy expenditure and respiratory quotient were determined by indirect calorimetry (weeks 4 and 8). Physical activity was measured using an accelerometer (weeks 3, 7, 11). Body composition was assessed using dual X-ray absorptiometry (week 12). MH significantly (p < 0.05) increased fasting serum glucagon-like peptide-1 and post-prandial serum ghrelin. MH tended (p < 0.1) to increase fasting serum gastric inhibitory peptide and decrease physical activity. Together, these findings suggest that dietary MH has the ability to promote satiation and lowers daily energy expenditure.

  12. Alcohol reward is increased after Roux-en-Y gastric bypass in dietary obese rats with differential effects following ghrelin antagonism.

    Directory of Open Access Journals (Sweden)

    Andras Hajnal

    Full Text Available Roux-en-Y gastric bypass (RYGB is one of the most successful treatments for severe obesity and associated comorbidities. One potential adverse outcome, however, is increased risk for alcohol use. As such, we tested whether RYGB alters motivation to self-administer alcohol in outbred dietary obese rats, and investigated the involvement of the ghrelin system as a potential underlying mechanism. High fat (60%kcal from fat diet-induced obese, non-diabetic male Sprague Dawley rats underwent RYGB (n = 9 or sham operation (Sham, n = 9 and were tested 4 months after surgery on a progressive ratio-10 (PR10 schedule of reinforcement operant task for 2, 4, and 8% ethanol. In addition, the effects of the ghrelin-1a-receptor antagonist D-[Lys3]-GHRP-6 (50, 100 nmol/kg, IP were tested on PR10 responding for 4% ethanol. Compared to Sham, RYGB rats made significantly more active spout responses to earn reward, more consummatory licks on the ethanol spout, and achieved higher breakpoints. Pretreatment with a single peripheral injection of D-[Lys3]-GHRP-6 at either dose was ineffective in altering appetitive or consummatory responses to 4% ethanol in the Sham group. In contrast, RYGB rats demonstrated reduced operant performance to earn alcohol reward on the test day and reduced consummatory responses for two subsequent days following the drug. Sensitivity to threshold doses of D-[LYS3]-GHRP-6 suggests that an augmented ghrelin system may contribute to increased alcohol reward in RYGB. Further research is warranted to confirm applicability of these findings to humans and to explore ghrelin-receptor targets for treatment of alcohol-related disorders in RYGB patients.

  13. H. pylori infection increases gastric mucosal COX2 and mTOR expression in chronic gastritis: Implications for cancer progression?

    Science.gov (United States)

    Badary, Dalia M; Rahma, Mohammed Zakaria Ali Abu; Ashmawy, Ahmed M; Hafez, Mohamed Z

    2017-09-01

    Helicobacter Pylori is a Gram-negative bacterium that infects the human stomach and plays an important role in the pathogenesis of chronic gastritis. H. pylori associated chronic gastritis affects various molecular markers related to gastric cancer development. The aim of this study to assess the effect of H. pylori infection on gastric mucosa and to explore its role in gastric carcinogenesis via COX2 and mTOR mucosal expression. This study comprised archival blocks from 60 dyspeptic patients who underwent gastric endoscopic biopsies for histopathological examination. The blocks were cut at 4 μm thicknesses, stained with hematoxylin and eosin to score, using updated Sydney system, and subjected to Giemsa stain to assess H. pylori infection. Then, immunohistochemical method was carried out to determine the expression of COX2 and mTOR. Increased H. pylori colonization was significantly correlated with increased severity of inflammation, activity, atrophy, intestinal metaplasia, and the presence of high-grade dysplasia. Also, studied molecular markers were significantly associated with increased H. pylori colonization and presence of severe metaplasia, atrophy, and dysplasia. These findings suggest that there is a positive feedback loop between H. pylori infection and the pathogenesis of gastric mucosal changes. Also, mTOR and COX2 over expression cause premalignant changes and subsequent tumor occurrence. This may help in providing innovative approaches for the detection of patients-with a higher chance of cancer development, and in trying to introduce effective therapy preventing tumor occurrence, or even using these molecular markers as potential targets for tumors treatment strategies. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Helicobacter pylori Infection Is Associated with an Increased Risk of Hyperemesis Gravidarum: A Meta-Analysis

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    Lin Li

    2015-01-01

    Full Text Available Background. Several studies have shown a possible involvement of Helicobacter pylori (H. pylori infection in individuals with hyperemesis gravidarum (HG, but the relationship remains controversial. This meta-analysis was performed to validate and strengthen the association between HG and H. pylori infection. Methods. PubMed, Embase, and Web of Science databases up to March 20, 2014, were searched to select studies on the prevalence of H. pylori infection between pregnant women with HG and the normal pregnant control subjects. Results. Of the HG cases, 1289 (69.6% were H. pylori-positive; however, 1045 (46.2% were H. pylori-positive in control group. Compared to the non-HG normal pregnant controls, infection rate of H. pylori was significantly higher in pregnant women with HG (OR = 3.34, 95% CI: 2.32–4.81, P<0.001. Subgroup analysis indicated that H. pylori infection was a risk factor of HG in Asia, Africa, and Oceania, especially in Africa (OR = 12.38, 95% CI: 7.12–21.54, P<0.001. Conclusions. H. pylori should be considered one of the risk factors of HG, especially in the developing countries. H. pylori eradication could be considered to relieve the symptoms of HG in some intractable cases.

  15. Central and peripheral mechanisms by which ghrelin regulates gut motility.

    Science.gov (United States)

    Peeters, T L

    2003-12-01

    Ghrelin is the recently discovered endogenous ligand for the growth hormone secretagogue receptor. This receptor had previously been characterized based on the stimulatory effect of synthetic peptides, enkephalin analogues, on growth hormone secretion by pituitary somatotrophs. Surprisingly, ghrelin is most abundant in the stomach, suggesting that it may have effects beyond the stimulation of growth hormone in the pituitary and that it is a new brain-gut peptide. There is now increasing evidence that ghrelin stimulates motor activity in the gastrointestinal tract. Thus ghrelin induces the migrating motor complex and accelerates gastric emptying. These are effects typical for motilin, the only peptide structurally related to ghrelin. Moreover, the receptors of both peptides are structurally related as well. The motor effects of ghrelin require rather high concentrations, while motilin at high concentrations stimulates growth hormone release. These data suggest cross-reactivity. However, in vitro binding and contractility studies in the rabbit, the classical model to study motilin agonists, show that ghrelin has very weak if any interaction with the motilin receptor. Similarly, in cell lines expressing the receptors for both peptides there is no evidence for cross-reactivity. This corresponds to the fact that the pharmacophore of both peptides is quite different. Therefore, the motor effects must be due to the stimulation of specific central or peripheral ghrelin receptors. In the guinea pig there is evidence from electrophysiology, immunohistochemistry and calcium imaging studies for ghrelin receptors on myenteric neurons. This provides the morphological basis for peripheral effects of ghrelin. In rats, ghrelin, but not motilin, enhances the response of muscle strips to electrical field stimulation by activating cholinergic pathways. In rabbits the opposite is true but some synthetic ghrelin agonists have weak effects which cannot be blocked by motilin antagonists

  16. Helicobacter pylori filtrate impairs spatial learning and memory in rats and increases β-amyloid by enhancing expression of presenilin-2

    Directory of Open Access Journals (Sweden)

    Xiu-Lian eWang

    2014-04-01

    Full Text Available Helicobacter pylori (H.pylori infection is related with a high risk of Alzheimer’s Disease (AD, but the intrinsic link between H.pylori infection and AD development is still missing. In the present study, we explored the effect of H.pylori infection on cognitive function and β-amyloid production in rats. We found that intraperitoneal injection of H.pylori filtrate induced spatial learning and memory deficit in rats with a simultaneous retarded dendritic spine maturation in hippocampus. Injection of H.pylori filtrate significantly increased Aβ42 both in the hippocampus and cortex, together with an increased level of presenilin-2 (PS-2, one key component of γ-secretase involved in Aβ production. Incubation of H.pylori filtrate with N2a cells which over-express APP also resulted in increased PS-2 expression and Aβ42 overproduction. Injection of Escherichia coli (E.coli filtrate, another common intestinal bacterium, had no effect on cognitive function in rats and Aβ production in rats and cells. These data suggest a specific effect of H.pylori on cognition and Aβ production. We conclude that soluble surface fractions of H.pylori may promote Aβ42 formation by enhancing the activity of γ-secretase, thus induce cognitive impairment through interrupting the synaptic function.

  17. Metabolic and Cardiovascular Effects of Ghrelin

    Science.gov (United States)

    Tesauro, Manfredi; Schinzari, Francesca; Caramanti, Miriam; Lauro, Renato; Cardillo, Carmine

    2010-01-01

    Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor, is synthesized as a preprohormone and then proteolytically processed to yield a 28-amino acid peptide. This peptide was originally reported to induce growth hormone release; large evidence, however, has indicated many other physiological activities of ghrelin, including regulation of food intake and energy balance, as well as of lipid and glucose metabolism. Ghrelin receptors have been detected in the hypothalamus and the pituitary, but also in the cardiovascular system, where ghrelin exerts beneficial hemodynamic activities. Ghrelin administration acutely improves endothelial dysfunction by increasing nitric oxide bioavailability and normalizes the altered balance between endothelin-1 and nitric oxide within the vasculature of patients with metabolic syndrome. Other cardiovascular effects of ghrelin include improvement of left ventricular contractility and cardiac output, as well as reduction of arterial pressure and systemic vascular resistance. In addition, antinflammatory and antiapoptotic actions of ghrelin have been reported both in vivo and in vitro. This review summarizes the most recent findings on the metabolic and cardiovascular effects of ghrelin through GH-dependent and -independent mechanisms and the possible role of ghrelin as a therapeutic molecule for treating cardiovascular diseases. PMID:20798901

  18. Acylation type determines ghrelin's effects on energy homeostasis in rodents

    DEFF Research Database (Denmark)

    Heppner, Kristy; Chaudhary, Nilika; Müller, Timo D;

    2012-01-01

    Ghrelin is a gastrointestinal polypeptide that acts through the ghrelin receptor (GHSR) to promote food intake and increase adiposity. Activation of GHSR requires the presence of a fatty-acid (FA) side chain on amino acid residue serine 3 of the ghrelin molecule. However, little is known about th...

  19. Antimicrobial susceptibility testing for Helicobacter pylori in times of increasing antibiotic resistance.

    Science.gov (United States)

    Smith, Sinéad M; O'Morain, Colm; McNamara, Deirdre

    2014-08-07

    The gram-negative bacterium Helicobacter pylori (H. pylori) causes chronic gastritis, gastric and duodenal ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma. Treatment is recommended in all symptomatic patients. The current treatment options for H. pylori infection are outlined in this review in light of the recent challenges in eradication success, largely due to the rapid emergence of antibiotic resistant strains of H. pylori. Antibiotic resistance is a constantly evolving process and numerous studies have shown that the prevalence of H. pylori antibiotic resistance varies significantly from country to country, and even between regions within the same country. In addition, recent data has shown that previous antibiotic use is associated with harbouring antibiotic resistant H. pylori. Local surveillance of antibiotic resistance is warranted to guide clinicians in their choice of therapy. Antimicrobial resistance is assessed by H. pylori culture and antimicrobial susceptibility testing. Recently developed molecular tests offer an attractive alternative to culture and allow for the rapid molecular genetic identification of H. pylori and resistance-associated mutations directly from biopsy samples or bacterial culture material. Accumulating evidence indicates that surveillance of antimicrobial resistance by susceptibility testing is feasible and necessary to inform clinicians in their choice of therapy for management of H. pylori infection.

  20. Acetylcholine regulates ghrelin secretion in humans

    NARCIS (Netherlands)

    F. Broglio (Fabio); E. Ghigo (Ezio); C. Gottero; F. Prodam (Flavia); S. Destefanis; A. Benso; C. Gauna (Carlotta); L.J. Hofland (Leo); E. Arvat; A-J. van der Lely (Aart-Jan); P.M. van Koetsveld (Peter)

    2004-01-01

    textabstractGhrelin secretion has been reportedly increased by fasting and energy restriction but decreased by food intake, glucose, insulin, and somatostatin. However, its regulation is still far from clarified. The cholinergic system mediates some ghrelin actions, e.g. stimulatio

  1. Polymorphisms of the DNA methyltransferase 1 associated with reduced risks of Helicobacter pylori infection and increased risks of gastric atrophy.

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    Jing Jiang

    Full Text Available INTRODUCTION: DNA methyltransferase-1(DNMT1 is an important enzyme in determining genomic methylation patterns in mammalian cells. We investigated the associations between SNPs in the DNMT1 gene and risks of developing H. pylori seropositivity, gastric atrophy and gastric cancer in the Chinese population. METHODS: The study consisted of 447 patients with gastric cancer; 111 patients with gastric atrophy; and 961 healthy controls. Five SNPs, rs10420321, rs16999593, rs8101866, rs8111085 and rs2288349 of the DNMT1 gene were genotyped. Anti-H.pylori IgG was detected by ELISA. Gastric atrophy was screened by the level of serum pepsinogen Ι and II and then confirmed by endoscopy and histopatholgical examinations. RESULTS: The age- and sex-adjusted OR of H. pylori seropositivity was 0.67 (95%CI: 0.51-0.87 for rs8111085 TC/CC genotypes, significantly lower than the TT genotype in healthy controls. The adjusted OR of H.pylori seropositivity was 0.68 (95%CI: 0.52-0.89 for rs10420321 AG/GG genotypes. In addition, patients carrying rs2228349 AA genotype have a significantly increased risk for H.pylori seropositivity (OR=1.67; 95%CI: 1.02-2.75. Further haplotype analyses also showed that the ATTTG and ATCTA are significantly associated with increased risks in H.pylori infection compared to the GTCCG haplotype (OR=1.38, 95%CI: 1.08-1.77; OR=1.40, 95% CI: 1.09-1.80. The adjusted ORs of gastric atrophy were 1.66 (95%CI: 1.06-2.61 for rs10420321 GG genotype, and 1.67 (95%CI 1.06-2.63, P=0.03 for rs8111085 CC genotype, but no association was found between SNPs in the DNMT1 gene and risk of developing gastric cancer. CONCLUSIONS: Individuals with rs10420321 GG and rs8111085 CC genotype of the DNMT1 gene were associated with reduced risks for H.pylori infection. On the other hand, higher risks of gastric atrophy were found in the carriers with these two genotypes compared to other genotypes. Our results suggested that SNPs of DNMT1 could be used as genotypic

  2. The role of ghrelin in the organism

    Directory of Open Access Journals (Sweden)

    Beata Polińska

    2011-01-01

    Full Text Available Ghrelin was discovered in 1999 as an endogenous ligand of the growth hormone secretagogue receptor (GHS-R. About 60–70�0of ghrelin in the blood is released from oxyntic cells (X/A-like cells of the stomach body and fundus. Ghrelin acts via interactions with specific receptors located, for example, in the hypothalamus, pituitary gland, pancreas, kidneys, myocardium, blood vessels, adipose tissue, ovaries and placenta. Ghrelin is directly related to the control of energy balance through appetite stimulation, food intake increase and meal initiation as well as reduction of adipose tissue utilization. Moreover, ghrelin increases hydrochloric acid secretion and gastrin release, controls gastric motility, and also protects the mucous membrane of the stomach and intestine. Besides its effects on the gastrointestinal tract, ghrelin influences the cardiovascular system, bone metabolism, insulin secretion, gonad function and the immune system. It exerts anti-inflammatory effects and inhibits apoptosis of cardiomyocytes and endothelium. The plasma ghrelin level depends on the nutrition level and lifestyle factors. This article describes the most important functions of ghrelin in the organism.

  3. Human Lysozyme Synergistically Enhances Bactericidal Dynamics and Lowers the Resistant Mutant Prevention Concentration for Metronidazole to Helicobacter pylori by Increasing Cell Permeability

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    Xiaolin Zhang

    2016-10-01

    Full Text Available Metronidazole (MNZ is an effective agent that has been employed to eradicate Helicobacter pylori (H. pylori. The emergence of broad MNZ resistance in H. pylori has affected the efficacy of this therapeutic agent. The concentration of MNZ, especially the mutant prevention concentration (MPC, plays an important role in selecting or enriching resistant mutants and regulating therapeutic effects. A strategy to reduce the MPC that can not only effectively treat H. pylori but also prevent resistance mutations is needed. H. pylori is highly resistant to lysozyme. Lysozyme possesses a hydrolytic bacterial cell wall peptidoglycan and a cationic dependent mode. These effects can increase the permeability of bacterial cells and promote antibiotic absorption into bacterial cells. In this study, human lysozyme (hLYS was used to probe its effects on the integrity of the H. pylori outer and inner membranes using as fluorescent probe hydrophobic 1-N-phenyl-naphthylamine (NPN and the release of aspartate aminotransferase. Further studies using a propidium iodide staining method assessed whether hLYS could increase cell permeability and promote cell absorption. Finally, we determined the effects of hLYS on the bactericidal dynamics and MPC of MNZ in H. pylori. Our findings indicate that hLYS could dramatically increase cell permeability, reduce the MPC of MNZ for H. pylori, and enhance its bactericidal dynamic activity, demonstrating that hLYS could reduce the probability of MNZ inducing resistance mutations.

  4. Ghrelin levels in chronic periodontitis patients.

    Science.gov (United States)

    Yılmaz, Gülin; Kırzıoğlu, Fatma Yeşim; Doğuç, Duygu Kumbul; Koçak, Havva; Orhan, Hikmet

    2014-01-01

    Ghrelin is a peptide hormone that has modulatory effects on the immune system. This study was designed to evaluate plasma ghrelin levels in patients with chronic periodontitis and to investigate if a relationship exists between ghrelin and periodontal parameters, serum cytokines, and bone turnover markers. Thirty-five chronic periodontitis patients (CP) and periodontal healthy individuals (C) were included in this study. Periodontal parameters were recorded. Blood samples were obtained to determine the levels of total and acylated ghrelin, interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), the soluble receptor activator nuclear factor kappaB ligand (sRANKL), alkaline phosphatase (ALP), and osteocalcin (OSC). Plasma levels of total and acylated ghrelin were significantly elevated in the CP group compared with the C group (p periodontal parameters. Our results indicate an increase of total and acylated ghrelin levels in patients with chronic periodontitis. Further, studies in larger populations (which could include ghrelin levels in gingival tissue, gingival crevicular fluid, and saliva) are needed in order to confirm the role of ghrelin in periodontal disease.

  5. Metabolic and cardiovascular effects of ghrelin

    Directory of Open Access Journals (Sweden)

    E V Kirienkova

    2012-03-01

    Full Text Available Ghrelin is an endogenous ligand for growth hormone receptor, which is synthesized as a prohormone, and then proteolytically converted into 28-amino acid peptide. This peptide stimulates the secretion of growth hormone, regulates food intake, effect on carbohydrate and lipid metabolism. Ghrelin enhances the bioavailability of nitric oxide and maintains the balance between endothelin-1 and nitric oxide in the vascular wall. It increases cardiac output, and reduces blood pressure and systemic vascular resistance. Antiinflammatory effect of ghrelin is also appreciated. Since ghrelin is a circulating peptide that stimulates appetite and regulate energy balance, and its role in the development of obesity and type 2 diabetes it is the subject of intense research. A variety of metabolic functions of ghrelin requires extreme caution in the use of therapeutic approaches aimed at the stimulation or blockade of its action.

  6. Serum ghrelin; a new surrogate marker of gastric mucosal alterations in upper gastrointestinal carcinogenesis.

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    Alireza Sadjadi

    Full Text Available BACKGROUND: A few studies have indicated inverse relationships between serum ghrelin and gastric and esophageal cancers but those associations have been restricted to specific populations, including smokers and overweight individuals. We examined the association between ghrelin and gastroesophageal cancers and atrophic gastritis in a population-based setting. METHODS: In total 220 gastroesophageal cancers, comprising non-cardia and cardia gastric cancer, esophageal adenocarcinoma, esophageal squamous cell carcinoma (SCC and age and gender-matched controls were recruited. Serum ghrelin, pepsinogen I/II ratio (PGI/II and anti-H.pylori IgG antibodies were measured. Relationships between ghrelin and gastroesophageal cancers, after adjustment for PGI/II ratio, H.pylori status and smoking, were tested using logistic regression. Furthermore, in 125 endoscopically normal volunteers, with and without histological atrophic gastritis, the relationship with ghrelin was compared. RESULTS: Serum ghrelin (lowest vs. highest quintile was inversely associated with gastric cancer: OR (95% CI 8.71 (1.70-44.59 for cardia and 6.58 (1.26-34.46 for non-cardia cancer. Lower serum ghrelin was also associated with esophageal SCC: OR (95% CI 5.69 (1.36-23.78, but not with esophageal adenocarcinoma. A similar association was observed between gastric cancer (cardia and non-cardia and esophageal SCC when serum ghrelin was analysed as a continuous scaled variable. In endoscopically-normal volunteers, extensive atrophic gastritis was associated with low serum ghrelin [OR (95% CI 0.25 (0.10-0.64]. CONCLUSION: Inverse associations between ghrelin and some gastroesophageal cancers suggest a potential role for serum ghrelin as a biomarker of upper gastrointestinal cancers and atrophic gastritis. In areas with a high incidence of gastric and/or esophageal cancer, screening might be more effectively targeted to individuals with low serum ghrelin in addition to the PGI/II ratio.

  7. Ghrelin's second life: From appetite stimulator to glucose regulator

    Institute of Scientific and Technical Information of China (English)

    Pieter-Jan Verhulst; Inge Depoortere

    2012-01-01

    Ghrelin,a 28 amino acid peptide hormone produced by the stomach,was the first orexigenic hormone to be discovered from the periphery.The octanoyl modification at Ser3,mediated by ghrelin O-acyltransferase (GOAT),is essential for ghrelin's biological activity.Ghrelin stimulates food intake through binding to its receptor (GRLN-R) on neurons in the arcuate nucleus of the hypothalamus.Ghrelin is widely expressed throughout the body; accordingly,it is implicated in several other physiological functions,which include growth hormone release,gastric emptying,and body weight regulation.Ghrelin and GRLN-R expression are also found in the pancreas,suggesting a local physiological role.Accordingly,several recent studies now point towards an important role for ghrelin and its receptor in the regulation of blood glucose homeostasis,which is the main focus of this review.Several mechanisms of this regulation by ghrelin have been proposed,and one possibility is through the regulation of insulin secretion.Despite some controversy,most studies suggest that ghrelin exerts an inhibitory effect on insulin secretion,resulting in increased circulating glucose levels.Ghrelin may thus be a diabetogenic factor.Obesity-related type 2 diabetes has become an increasingly important health problem,almost reaching epidemic proportions in the world; therefore,antagonists of the ghrelin-GOAT signaling pathway,which will tackle both energy-and glucose homeostasis,may be considered as promising new therapies for this disease.

  8. LACK OF ASSOCIATION BETWEEN HELICOBACTER PYLORI'S VIRULENCE AND INCREASED SERUM C-REACTIVE PROTEIN LEVELS IN FUNCTIONAL DYSPEPTIC PATIENTS

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    Huander Felipe ANDREOLLA

    Full Text Available ABSTRACT Background Recently, a great variety of studies aimed to investigate and even suggestHelicobacter pylori as an important key factor in gastrointestinal and non-gastrointestinal events development. The well-established relationship between bacterial virulence and increased risk for peptic ulcer or gastric carcinoma is not so clear when comparing inflammation markers alterations, such C-reactive protein, with the pathogen. Objective The objective of this study was to evaluate the presence of H. pylori, bacterial virulence and C-reactive protein serum levels in individuals diagnosed with functional dyspepsia. Methods Were prospectively included in this study 489 dyspeptic individuals. They fulfill Rome III clinical criteria for the diagnosis of functional dyspepsia with no organic disease at endoscopy. The bacterial infection was established by histology and urease rapid test. The levels of serum C-reactive protein were obtained by immunonefelometry and CagA status ofH. pylori positive individuals was determined through an imunoenzimatic assay. Results Prevalence rate of H. pylori was 66.3% and virulence factor CagA was detected in nearly 43% of positive samples. In addition, it has been noticed an association between Ilex paraguariensis(yerba maté consumption and pathogen's prevalence. An important effect of bacterial infection on inflammation was only observed in gastric epithelium. Conclusion No systemic response to the pathogen, measured through C-reactive protein levels, was observed, regardless of CagA status. Otherwise, the intake of yerba maté should be considered as a cultural factor possibly related toH. pylori's transmission.

  9. Altered ghrelin secretion in mice in response to diet-induced obesity and Roux-en-Y gastric bypass

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    Aki Uchida

    2014-10-01

    Full Text Available The current study examined potential mechanisms for altered circulating ghrelin levels observed in diet-induced obesity (DIO and following weight loss resulting from Roux-en-Y gastric bypass (RYGB. We hypothesized that circulating ghrelin levels were altered in obesity and after weight loss through changes in ghrelin cell responsiveness to physiological cues. We confirmed lower ghrelin levels in DIO mice and demonstrated elevated ghrelin levels in mice 6 weeks post-RYGB. In both DIO and RYGB settings, these changes in ghrelin levels were associated with altered ghrelin cell responsiveness to two key physiological modulators of ghrelin secretion – glucose and norepinephrine. In DIO mice, increases in ghrelin cell density within both the stomach and duodenum and in somatostatin-immunoreactive D cell density in the duodenum were observed. Our findings provide new insights into the regulation of ghrelin secretion and its relation to circulating ghrelin within the contexts of obesity and weight loss.

  10. Virulence factors of Helicobacter pylori vacA increase markedly gastric mucosal TGF-β1 mRNA expression in gastritis patients.

    Science.gov (United States)

    Rahimian, Ghorbanali; Sanei, Mohammad Hosein; Shirzad, Hedayatollah; Azadegan-Dehkordi, Fatemeh; Taghikhani, Afshin; Salimzadeh, Loghman; Hashemzadeh-Chaleshtori, Morteza; Rafieian-Kopaei, Mahmoud; Bagheri, Nader

    2014-01-01

    Helicobacter pylori (H. pylori) infection is the main cause of gastric inflammation. Regulatory T cells (Treg cells) suppress the activation and proliferation of antigen-specific T cells and mediate immunologic tolerance. TGF-β1 was shown to be secreted in a subset of Treg cells known as 'Th3 cells'. These cells have not been sufficiently studied in context to H. pylori-induced inflammation in human gastric mucosa. In this study we therefore, aimed to investigate the expression of TGF-β1 in the context of H. pylori colonization in chronic gastritis, to examine the relationship between it and histopathologic findings and to compare it with virulence factors. Total RNA was extracted from gastric biopsies of 48 H. pylori-infected patients and 38 H. pylori-negative patients with gastritis. Mucosal TGF-β1 mRNA expression in H. pylori-infected and uninfected gastric biopsies was determined by real-time PCR. Presence of vacA, cagA, iceA, babA2 and oipA virulence factors was evaluated using PCR. TGF-β1 mRNA expression was significantly increased in biopsies of H. pylori-infected patients compared to H. pylori-uninfected patients. There was association between virulence factors and TGF-β1 mRNA expression. TGF-β1 mRNA expression in mucosa was significantly higher in patients with vacA s1 and s1m1. TGF-β1 may play an important role in the inflammatory response and promote the chronic and persistent inflammatory changes in the gastric. This may ultimately influence the outcome of H. pylori-associated diseases that arise within the context of gastritis and vacA may suffice to induce expression of TGF-β1 mRNA. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. A novel human ghrelin variant (In1-ghrelin and ghrelin-O-acyltransferase are overexpressed in breast cancer: potential pathophysiological relevance.

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    Manuel D Gahete

    Full Text Available The human ghrelin gene, which encodes the ghrelin and obestatin peptides, contains 5 exons (Ex, with Ex1-Ex4 encoding a 117 amino-acid (aa preproprotein that is known to be processed to yield a 28-aa (ghrelin and/or a 23-aa (obestatin mature peptides, which possess biological activities in multiple tissues. However, the ghrelin gene also encodes additional peptides through alternative splicing or post-translational modifications. Indeed, we previously identified a spliced mRNA ghrelin variant in mouse (In2-ghrelin-variant, which is regulated in a tissue-dependent manner by metabolic status and may thus be of biological relevance. Here, we have characterized a new human ghrelin variant that contains Ex0-1, intron (In 1, and Ex2 and lacks Ex3-4. This human In1-ghrelin variant would encode a new prepropeptide that conserves the first 12aa of native-ghrelin (including the Ser3-potential octanoylation site but has a different C-terminal tail. Expression of In1-variant was detected in 22 human tissues and its levels were positively correlated with those of ghrelin-O-acyltransferase (GOAT; p = 0.0001 but not with native-ghrelin expression, suggesting that In1-ghrelin could be a primary substrate for GOAT in human tissues. Interestingly, levels of In1-ghrelin variant expression in breast cancer samples were 8-times higher than those of normal mammary tissue, and showed a strong correlation in breast tumors with GOAT (p = 0.0001, ghrelin receptor-type 1b (GHSR1b; p = 0.049 and cyclin-D3 (a cell-cycle inducer/proliferation marker; p = 0.009, but not with native-ghrelin or GHSR1a expression. Interestingly, In1-ghrelin variant overexpression increased basal proliferation of MDA-MB-231 breast cancer cells. Taken together, our results provide evidence that In1-ghrelin is a novel element of the ghrelin family with a potential pathophysiological role in breast cancer.

  12. Sustained appetite improvement in malnourished dialysis patients by daily ghrelin treatment

    National Research Council Canada - National Science Library

    Ashby, Damien R; Ford, Heather E; Wynne, Katie J; Wren, Alison M; Murphy, Kevin G; Busbridge, Mark; Brown, Edwina A; Taube, David H; Ghatei, Mohammad A; Tam, Frederick W K; Bloom, Stephen R; Choi, Peter

    2009-01-01

    ... malnourished dialysis patients. Ghrelin administration increased ghrelin levels in circulation, modestly reduced blood pressure for up to 2 h, and immediately and significantly increased appetite, with an increase in energy intake...

  13. Ablation of ghrelin receptor in leptin-deficient ob/ob mice has paradoxical effects on glucose homeostasis when compared with ablation of ghrelin in ob/ob mice

    Science.gov (United States)

    The orexigenic hormone ghrelin is important in diabetes because it has an inhibitory effect on insulin secretion. Ghrelin ablation in leptin-deficient ob/ob (Ghrelin(-/-):ob/ob) mice increases insulin secretion and improves hyperglycemia. The physiologically relevant ghrelin receptor is the growth ...

  14. Effects of ghrelin on food intake and neuroendocrine function in sheep.

    Science.gov (United States)

    Sugino, T; Hasegawa, Y; Kurose, Y; Kojima, M; Kangawa, K; Terashima, Y

    2004-07-01

    Ghrelin, a novel acylated peptide, is the endogenous ligand for growth hormone secretagogue (GHS) receptor. Ghrelin is produced mainly in the oxyntic glands of the stomach, but also produced in the intestines, kidneys, hypothalamus and pituitary gland. Circulating ghrelin levels have been shown to rise before a meal and fall afterwards, suggesting that anticipation of a meal may stimulate secretion. In some species, ghrelin administration has been shown to stimulate growth hormone (GH) secretion, and to cause weight gain by increasing food intake and reducing metabolic utilization of fat. Furthermore, intracerebroventricular and intravascular administration of ghrelin increases gastric acid output in a dose-dependent manner. Thus, ghrelin may play an important role in controlling feeding behavior and energy homeostasis. We have investigated the role of ghrelin in the control of feeding and neuroendocrine function in ruminants using sheep as an experimental model. This mini review describes mechanisms regulating ghrelin secretion at feeding time, and also focuses on the neuroendocrine functions of ghrelin.

  15. Dose-dependent response of plasma ghrelin and growth hormone concentrations to bovine ghrelin in Holstein heifers.

    Science.gov (United States)

    ThidarMyint, Hnin; Yoshida, Hiroko; Ito, Tetsuya; Kuwayama, Hideto

    2006-06-01

    The stimulatory effect of the novel gastric-derived hormone, ghrelin, on growth hormone (GH) secretion has been reported in domestic animals as well as in humans and rats. The octanoyl modification on the Ser3 residue of ghrelin appears to be essential for its endocrine activity. A major portion of circulatory ghrelin lacks acylation but possesses some biological activities other than GH stimulation; therefore, both types of acylated and des-acyl ghrelin are supposed to be important for energy homeostasis. The effects of pharmacological doses of rat and/or human ghrelin on GH secretion have been reported recently in ruminants; however, the physiological effect of exogenous bovine ghrelin on its own plasma level and on GH secretion is still unknown. Moreover, the RIA systems for the measurement of bovine active ghrelin and for bovine total ghrelin including acylated ghrelin, des-acyl ghrelin and all ghrelin peptides with an intact bovine C-terminal have not yet been validated. In this study, we established the RIA system for bovine ghrelin, and the dose-dependent effects of synthesized acylated bovine ghrelin(1-27) on plasma active and total ghrelin, GH, insulin and metabolites were measured in Holstein heifers. Six animals were intravenously injected with synthesized acylated bovine ghrelin (0, 0.1, 0.5, 1.0, 5.0, 10.0 microg/kg body weight (BW)) and plasma hormone concentrations were measured from serially collected samples. Bovine ghrelin RIA showed that the basal level of total ghrelin is approximately 16 times higher than that of active ghrelin in bovine plasma. Both forms of ghrelin were increased in a dose-dependent manner in response to bovine ghrelin injections, peak values were reached at 5 min after administration and returned to pre-injected values within 15 min. Plasma GH was responsive to all doses of bovine ghrelin in a dose-dependent manner, peaked as early as at 5-10 min after injection and returned to the basal value within 60 min. The GH area

  16. The regulation of circulating ghrelin - with recent updates from cell-based assays.

    Science.gov (United States)

    Iwakura, Hiroshi; Kangawa, Kenji; Nakao, Kazuwa

    2015-01-01

    Ghrelin is a stomach-derived orexigenic hormone with a wide range of physiological functions. Elucidation of the regulation of the circulating ghrelin level would lead to a better understanding of appetite control in body energy homeostasis. Earlier studies revealed that circulating ghrelin levels are under the control of both acute and chronic energy status: at the acute scale, ghrelin levels are increased by fasting and decreased by feeding, whereas at the chronic scale, they are high in obese subjects and low in lean subjects. Subsequent studies revealed that nutrients, hormones, or neural activities can influence circulating ghrelin levels in vivo. Recently developed in vitro assay systems for ghrelin secretion can assess whether and how individual factors affect ghrelin secretion from cells. In this review, on the basis of numerous human, animal, and cell-based studies, we summarize current knowledge on the regulation of circulating ghrelin levels and enumerate the factors that influence ghrelin levels.

  17. Expression of CD86 and increased infiltration of NK cells are associated with Helicobacter pylori-dependent state of early stage high-grade gastric MALT lymphoma

    Institute of Scientific and Technical Information of China (English)

    Sung-Hsin Kuo; Jaw-Town Lin; Ann-Lii Cheng; Li-Tzong Chen; Chi-Long Chen; Shin-Lian Doong; Kun-Huei Yeh; Ming-Shiang Wu; Tsui-Lien Mao; Hui-Chen Hsu; Hsiu-Po Wang

    2005-01-01

    AIM: A high percentage of early-stage high-grade gastric mucosa-associated lymphoid tissue (MALT) lymphomas remain Helicobacter pylori(H pylori)-dependent. However,unlike their low-grade counterparts, high-grade gastric MALT lymphomas may progress rapidly if unresponsive to H pylori eradication. It is mandatory to identify markers that may predict the H pylori-dependent status of these tumors. Proliferation of MALT lymphoma cells depends on cognate help and cell-to-cell contact of H pylori-specific intratumoral T-cells. To examine whether the expression of co-stimulatory marker CD86 (B7.2) and the infiltration of CD56 (+) natural killer (NK) cells can be useful markers to predict Hpylori-dependent status of high-grade gastric MALT lymphoma.METHODS: Lymphoma biopsies from 26 patients who had participated in a prospective study of H pylori-eradication for stage IE high-grade gastric MALT lymphomas were evaluated. Tumors that resolved to Wotherspoon grade Ⅱ or less after H pylorieradication were classified as H pyloridependent; others were classified as H pylori-independent.The infiltration of NK cells and the expression of CD86 in pre-treatment paraffin-embedded lymphoma tissues were determined by immunohistochemistry.RESULTS: There were 16 H pylori-dependent and 10H pylori-independent cases. CD86 expression was detected in 11 (68.8%) of 16 Hpyiori-dependent cases but in none of 10 Hpylori-independent cases (P = 0.001).H pylori-dependent high-grade gastric MALT lymphomas contained significantly higher numbers of CD56 (+) NK cells than H pylori-independent cases (2.8±1.4% vs 1.1±0.8%; P = 0.003). CD86 positive MALT lymphomas also showed significantly increased infiltration of CD56 (+)NK cells compared to CD86-negative cases (2.9±1.1% vs1.4±1.3%; P= 0.005).CONCLUSION: These results suggest that the expression of co-stimulatory marker CD86 and the increased infiltration of NK cells are associated with H pylori-dependent state of early-stage high-grade gastric MALT

  18. Ghrelin directly stimulates glucagon secretion from pancreatic alpha-cells.

    Science.gov (United States)

    Chuang, Jen-Chieh; Sakata, Ichiro; Kohno, Daisuke; Perello, Mario; Osborne-Lawrence, Sherri; Repa, Joyce J; Zigman, Jeffrey M

    2011-09-01

    Previous work has demonstrated that the peptide hormone ghrelin raises blood glucose. Such has been attributed to ghrelin's ability to enhance GH secretion, restrict insulin release, and/or reduce insulin sensitivity. Ghrelin's reported effects on glucagon have been inconsistent. Here, both animal- and cell-based systems were used to determine the role of glucagon in mediating ghrelin's effects on blood glucose. The tissue and cell distribution of ghrelin receptors (GHSR) was evaluated by quantitative PCR and histochemistry. Plasma glucagon levels were determined following acute acyl-ghrelin injections and in pharmacological and/or transgenic mouse models of ghrelin overexpression and GHSR deletion. Isolated mouse islets and the α-cell lines αTC1 and InR1G9 were used to evaluate ghrelin's effects on glucagon secretion and the role of calcium and ERK in this activity. GHSR mRNA was abundantly expressed in mouse islets and colocalized with glucagon in α-cells. Elevation of acyl-ghrelin acutely (after sc administration, such that physiologically relevant plasma ghrelin levels were achieved) and chronically (by slow-releasing osmotic pumps and as observed in transgenic mice harboring ghrelinomas) led to higher plasma glucagon and increased blood glucose. Conversely, genetic GHSR deletion was associated with lower plasma glucagon and reduced fasting blood glucose. Acyl-ghrelin increased glucagon secretion in a dose-dependent manner from mouse islets and α-cell lines, in a manner requiring elevation of intracellular calcium and phosphorylation of ERK. Our study shows that ghrelin's regulation of blood glucose involves direct stimulation of glucagon secretion from α-cells and introduces the ghrelin-glucagon axis as an important mechanism controlling glycemia under fasting conditions.

  19. Ghrelin; The Renown Hormone

    Directory of Open Access Journals (Sweden)

    H. Murat Bilgin

    2006-01-01

    Full Text Available Ghrelin , a 28 amino acid gastric peptide, was found to be a potent releaser of GH and in addition, actively participate in controlling energy balance and the regulation of food intake. Specifically, plasma ghrelin originates in the oxyntic gland where A-like cells exist and is secreted into the bloodstream. Lower concentrations have also been reported at various regions in the body. It is well known that ghrelin participates in the regulation of many functions in the body.

  20. Rikkunshito and Ghrelin

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    Tomohisa Hattori

    2010-01-01

    Full Text Available Rikkunshito is a popular Japanese traditional medicine that is prescribed in Japan to treat various gastrointestinal tract disorders. In a double-blind controlled study, rikkunshito significantly ameliorated dysmotility-like dyspepsia and brought about a generalized improvement in upper gastric symptoms such as nausea and anorexia when compared with a control group. Several studies in rats have shown enhanced gastric emptying and a protective effect on gastric mucosa injury with rikkunshito administration. In addition, rikkunshito in combination with an anti-emetic drug is effective against anorexia and vomiting that occur as adverse reactions to chemotherapy in patients with advanced breast cancer. However, the mechanism by which rikkunshito alleviates gastrointestinal disorders induced by anticancer agents remains unclear. It has recently been shown that rikkunshito ameliorates cisplatin-induced anorexia by mediating an increase in the circulating ghrelin concentration. Moreover, Fujitsuka et al. found that decreased contractions of the antrum and duodenum in rats treated with a selective serotonin reuptake inhibitor were reversed by rikkunshito via enhancement of the circulating ghrelin concentration. These findings show that rikkunshito may be useful for treatment of anorexia and may provide a new strategy for improvement of upper gastrointestinal dysfunction.

  1. Acute effects of ghrelin administration on glucose and lipid metabolism

    DEFF Research Database (Denmark)

    Vestergaard, Esben Thyssen; Djurhuus, Christian Born; Gjedsted, Jakob;

    2007-01-01

    CONTEXT: Ghrelin infusion increases plasma glucose and nonesterified fatty acids, but it is uncertain whether this is secondary to the concomitant release of GH. OBJECTIVE: Our objective was to study direct effects of ghrelin on substrate metabolism. DESIGN: This was a randomized, single-blind, p......CONTEXT: Ghrelin infusion increases plasma glucose and nonesterified fatty acids, but it is uncertain whether this is secondary to the concomitant release of GH. OBJECTIVE: Our objective was to study direct effects of ghrelin on substrate metabolism. DESIGN: This was a randomized, single...

  2. Secretory dynamics of ghrelin in adolescent girls with anorexia nervosa and healthy adolescents.

    Science.gov (United States)

    Misra, Madhusmita; Miller, Karen K; Kuo, Kelly; Griffin, Kathryn; Stewart, Victoria; Hunter, Emily; Herzog, David B; Klibanski, Anne

    2005-08-01

    Ghrelin is an orexigenic peptide and a growth hormone (GH) secretagogue. Secretory dynamics of ghrelin have not been characterized in adolescents with anorexia nervosa (AN). We hypothesized that, compared with healthy adolescents, girls with AN would have increased ghrelin concentrations measured over 12 h of nocturnal sampling from increased basal and pulsatile secretion, and endogenous ghrelin would independently predict GH and cortisol. We examined ghrelin concentration and secretory dynamics in 22 girls with AN and 18 healthy adolescents 12-18 yr old. Associations between ghrelin, various hormones, and measures of insulin resistance were examined. On Cluster analysis, girls with AN had higher ghrelin concentrations than controls, including total area under the curve (AUC) (P = 0.002), nadir (P = 0.0006), and valley levels (P = 0.002). On deconvolution analysis, secretory burst amplitude (P = 0.03) and burst mass (P = 0.04) were higher in AN, resulting in higher pulsatile (P = 0.05) and total ghrelin secretion (P = 0.03). Fasting ghrelin independently predicted GH burst frequency (r = 0.44, P = 0.005). The nutritional markers body mass index and body fat predicted postglucose and valley ghrelin but not fasting levels. Ghrelin parameters were inversely associated with fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), leptin, and IGF-I. HOMA-IR was the most significant predictor of most ghrelin parameters. Valley ghrelin independently predicted cortisol burst frequency (52% of variability), and ghrelin parameters independently predicted total triiodothyronine and LH levels. Higher ghrelin concentrations in adolescents with AN are a consequence of increased secretory burst mass and amplitude. The most important predictor of ghrelin concentration is insulin resistance, and ghrelin in turn predicts GH and cortisol burst frequency.

  3. Review of novel aspects of the regulation of ghrelin secretion.

    Science.gov (United States)

    Al Massadi, Omar; Lear, Pamela V; Muller, Timo D; Lopez, Miguel; Dieguez, Carlos; Tschop, Matthias H; Nogueiras, Ruben

    2014-01-01

    The role of ghrelin in regulating metabolism and energy balance has been a subject of intense focus ever since its discovery. Ghrelin regulates energy balance in the short term by induction of appetite and in the longer term by increasing body weight and adiposity. It is the only known peripheral orexigenic hormone and one of the most potent endogenous orexigenic factors discovered to date. However, whilst extensively studied, the mechanism of ghrelin secretion is not well understood. A better understanding of the pathways controlling ghrelin secretion could be useful in the development of new therapeutic approaches to appetite-related disorders. Here, we discuss current knowledge of the processes that control ghrelin secretion, focusing on neural, chemical and hormonal stimuli. In addition, we share our view on the potential of targeting ghrelin for the treatment of eating disorders such as obesity, anorexia nervosa and cachexia.

  4. Helicobacter Pylori Associated Gastritis Increases Risk of Colorectal Polyps: a Hospital Based-Cross-Sectional Study in Nakhon Ratchasima Province, Northeastern Thailand.

    Science.gov (United States)

    Tongtawee, Taweesak; Kaewpitoon, Soraya; Kaewpitoon, Natthawut; Dechsukhum, Chavaboon; Leeanansaksiri, Wilairat; Loyd, Ryan A; Matrakool, Likit; Panpimanmas, Sukij

    2016-01-01

    Colorectal polyps are common in Thailand, particularly in the northeastern region. The present study aimed to determine any correlation between Helicobacter pylori-associated gastritis and colorectal polyps in the Thai population. A total of 303 patients undergoing esophagogastroduodenoscopy with colonoscopy for investigation of chronic abdominal pain participated in this study from November 2014 to October 2015. A diagnosis of Helicobacter pylori associated gastritis was made if the bacteria were seen on histopathological examination and a rapid urease test was positive. Colorectal polyps were confirmed by histological examination of colorectal biopsies. Patient demographic data were analyzed for correlations. The prevalence of colorectal polyps was 77 (25.4%), lesions being found more frequently in Helicobacter pylori infected patients than non-infected subjects [38.4% vs. 12.5%; Odds Ratio (OR) (95% CI): 2.26 (1.32 - 3.86), p gastritis were at high risk of having adenomas featuring dysplasia [OR (95% CI): 1.15 (1.16 - 7.99); P = 0.02]. There was no varaition in location of polyps, age group, sex and gastric lesions with respect to Helicobacter pylori status. This study showed that Helicobacter pylori associated gastritis is associated with an increased risk of colorectal polyps, especially adenomas with dysplasia in the Thai population. Patients with Helicobacter pylori-associated gastritis may benefit from concurrent colonoscopy for diagnosis of colorectal polyps as a preventive and early treatment for colorectal cancer.

  5. The Sweetener-Sensing Mechanisms of the Ghrelin Cell

    Science.gov (United States)

    Steensels, Sandra; Vancleef, Laurien; Depoortere, Inge

    2016-01-01

    Carbohydrate administration decreases plasma levels of the ‘hunger hormone’ ghrelin. The ghrelin cell is co-localized with the sweet taste receptor subunit, TAS1R3, and the gustatory G-protein, gustducin, both involved in the sensing of sweeteners by entero-endocrine cells. This study investigated the role of gustducin-mediated sweet taste receptor signaling on ghrelin secretion in a gastric ghrelinoma cell line, tissue segments and mice. The monosaccharide d-glucose and low-intensity sweetener oligofructose (OFS) decreased (p sweetener sucralose increased (p sweeteners by the ghrelin cell. PMID:27941594

  6. Effect of ghrelin on autonomic activity in healthy volunteers.

    Science.gov (United States)

    Soeki, Takeshi; Koshiba, Kunihiko; Niki, Toshiyuki; Kusunose, Kenya; Yamaguchi, Koji; Yamada, Hirotsugu; Wakatsuki, Tetsuzo; Shimabukuro, Michio; Minakuchi, Kazuo; Kishimoto, Ichiro; Kangawa, Kenji; Sata, Masataka

    2014-12-01

    Ghrelin is a novel growth hormone (GH)-releasing peptide originally isolated from the stomach. Recently, we have shown that ghrelin suppresses cardiac sympathetic activity and prevents early left ventricular remodeling in rats with myocardial infarction. In the present study, we evaluated the effect of ghrelin on autonomic nerve activity in healthy human subjects. An intravenous bolus of human synthetic ghrelin (10μg/kg) was administered to 10 healthy men (mean age, 33 years). Holter monitoring assessment was performed before and during 2h after the ghrelin therapy. The standard deviation of normal RR intervals (SDNN), square root of the mean of the sum of the squares of differences between adjacent RR intervals (rMSSD), high-frequency power (HF), and low-frequency power (LF) were analyzed. Blood samples were also obtained before and after the therapy. A single administration of ghrelin decreased both heart rate and blood pressure. Interestingly, ghrelin significantly decreased the LF and LF/HF ratio of heart rate variability and increased the SDNN, rMSSD, and HF. Ghrelin also elicited a marked increase in circulating GH, but not insulin-like growth factor-1. These data suggest that ghrelin might suppress cardiac sympathetic nerve activity and stimulate cardiac parasympathetic nerve activity. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Ghrelin and Metabolic Surgery

    Directory of Open Access Journals (Sweden)

    Dimitrios J. Pournaras

    2010-01-01

    Full Text Available Metabolic surgery is the most effective treatment for morbid obesity. Ghrelin has been implicated to play a role in the success of these procedures. Furthermore, these operations have been used to study the gut-brain axis. This article explores this interaction, reviewing the available data on changes in ghrelin levels after different surgical procedures.

  8. Ghrelin and cell differentiation

    Institute of Scientific and Technical Information of China (English)

    Geyang Xu; Yin Li; Wenjiao An; Weizhen Zhang

    2008-01-01

    Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor, is a gastric hormone that has been found to have a wide variety of biological functions. This review summarizes our current understanding of the effects of ghrelin on cell differentiation and tissue development, with an emphasis on the lineage determination of mesenchymal stem cells.

  9. The Sweetener-Sensing Mechanisms of the Ghrelin Cell

    Directory of Open Access Journals (Sweden)

    Sandra Steensels

    2016-12-01

    Full Text Available Carbohydrate administration decreases plasma levels of the ‘hunger hormone’ ghrelin. The ghrelin cell is co-localized with the sweet taste receptor subunit, TAS1R3, and the gustatory G-protein, gustducin, both involved in the sensing of sweeteners by entero-endocrine cells. This study investigated the role of gustducin-mediated sweet taste receptor signaling on ghrelin secretion in a gastric ghrelinoma cell line, tissue segments and mice. The monosaccharide d-glucose and low-intensity sweetener oligofructose (OFS decreased (p < 0.001 ghrelin secretion while the high-intensity sweetener sucralose increased (p < 0.001 ghrelin secretion in vitro. These effects were not mediated via the sweet taste receptor or glucose transporters (the sodium-dependent glucose cotransporter SGLT-1 and GLUT2. The effect of these compounds was mimicked ex vivo in gastric and jejunal segments from both wild type (WT and α-gustducin knockout (α-gust−/− mice. In vivo, the sensing of d-glucose was polarized since intragastric but not intravenous administration of d-glucose decreased (p < 0.05 ghrelin levels in an α-gustducin independent manner which involved inhibition of duodenal ghrelin release. In contrast, neither OFS nor sucralose affected ghrelin secretion in vivo. In conclusion, α-gustducin-mediated sweet taste receptor signaling does not play a functional role in the sensing of carbohydrates, or low- or high-intensity sweeteners by the ghrelin cell.

  10. Increased Helicobacter pylori-associated Gastric Cancer Risk in the Andean Region of Colombia Is Mediated by Spermine Oxidase

    Science.gov (United States)

    Chaturvedi, Rupesh; de Sablet, Thibaut; Asim, Mohammad; Piazuelo, M. Blanca; Barry, Daniel P.; Verriere, Thomas G.; Sierra, J. Carolina; Hardbower, Dana M.; Delgado, Alberto G.; Schneider, Barbara G.; Israel, Dawn A.; Romero-Gallo, Judith; Nagy, Toni A.; Morgan, Douglas R.; Murray-Stewart, Tracy; Bravo, Luis E.; Peek, Richard M.; Fox, James G.; Woster, Patrick M.; Casero, Robert A.; Correa, Pelayo; Wilson, Keith T.

    2014-01-01

    Helicobacter pylori infection causes gastric cancer, the third leading cause of cancer death worldwide. More than half of the world’s population is infected, making universal eradication impractical. Clinical trials suggest that antibiotic treatment only reduces gastric cancer risk in patients with non-atrophic gastritis (NAG), and is ineffective once preneoplastic lesions of multifocal atrophic gastritis (MAG) and intestinal metaplasia (IM) have occurred. Therefore, additional strategies for risk stratification and chemoprevention of gastric cancer are needed. We have implicated polyamines, generated by the rate limiting enzyme ornithine decarboxylase (ODC), in gastric carcinogenesis. During H. pylori infection, the enzyme spermine oxidase (SMOX) is induced, which generates hydrogen peroxide from the catabolism of the polyamine spermine. Herein, we assessed the role of SMOX in the increased gastric cancer risk in Colombia associated with the Andean mountain region when compared to the low risk region on the Pacific coast. When co-cultured with gastric epithelial cells, clinical strains of H. pylori from the high risk region induced more SMOX expression and oxidative DNA damage, and less apoptosis than low risk strains. These findings were not attributable to differences in the CagA oncoprotein. Gastric tissues from subjects from the high risk region exhibited greater levels of SMOX and oxidative DNA damage by immunohistochemistry and flow cytometry, and this occurred in NAG, MAG, and IM. In Mongolian gerbils, a prototype colonizing strain from the high risk region induced more SMOX, DNA damage, dysplasia and adenocarcinoma than a colonizing strain from the low risk region. Treatment of gerbils with either α-difluoromethylornithine (DFMO), an inhibitor of ODC, or MDL 72527, an inhibitor of SMOX, reduced gastric dysplasia and carcinoma, as well as apoptosis-resistant cells with DNA damage. These data indicate that aberrant activation of polyamine-driven oxidative

  11. Effects of ghrelin in energy balance and body weight homeostasis.

    Science.gov (United States)

    Mihalache, Laura; Gherasim, Andreea; Niță, Otilia; Ungureanu, Maria Christina; Pădureanu, Sergiu Serghei; Gavril, Radu Sebastian; Arhire, Lidia Iuliana

    2016-02-01

    Ghrelin is a gut peptide composed of 28 amino acids mostly secreted in the gastric fundus mucosa. It was isolated and described in 1999 by Kojima et al. and only three years later its specific receptor, GHSR1a, was also identified. Ghrelin, the endogenous ligand for the GH secretagogue receptor, is the only peripheral orexigenic hormone that activates the receptors to be found especially in the appetite center (hypothalamus and pituitary gland). Ghrelin is present in human plasma in two forms: an inactive form known as deacylated ghrelin, and an active form called acylated ghrelin synthesized under the action of ghrelin O-acyltransferase enzyme (GOAT). The literature even mentions an extremely complex ghrelin/GOAT/GHSR system involved in the regulation of human energy, metabolism and adaptation of energy homeostasis to environmental changes. In humans, there is a preprandial rise and a postprandial fall in plasma ghrelin levels, which strongly suggest that the peptide plays a physiological role in meal initiation and may be employed in determining the amount and quality of ingested food. Besides the stimulation of food intake, ghrelin determines a decrease in energy expenditure and promotes the storage of fatty acids in adipocytes. Thus, in the human body ghrelin induces a positive energy balance, an increased adiposity gain, as well as an increase in caloric storage, seen as an adaptive mechanism to caloric restriction conditions. In the current world context, when we are witnessing an increasing availability of food and a reduction of energy expenditure to a minimum level, these mechanisms have become pathogenic. As a consequence, the hypothesis that ghrelin is involved in the current obesity epidemic has been embraced by many scholars and researchers.

  12. Reduced ghrelin secretion in the hypothalamus of rats due to cisplatin-induced anorexia.

    Science.gov (United States)

    Yakabi, Koji; Sadakane, Chiharu; Noguchi, Masamichi; Ohno, Shino; Ro, Shoki; Chinen, Katsuya; Aoyama, Toru; Sakurada, Tomoya; Takabayashi, Hideaki; Hattori, Tomohisa

    2010-08-01

    Although chemotherapy with cisplatin is a widely used and effective cancer treatment, the undesirable gastrointestinal side effects associated with it, such as nausea, vomiting, and anorexia, markedly decrease patients' quality of life. To elucidate the mechanism underlying chemotherapy-induced anorexia, focusing on the hypothalamic ghrelin secretion-anorexia association, we measured hypothalamic ghrelin secretion in fasted and cisplatin-treated rats. Hypothalamic ghrelin secretion changes after vagotomy or administration of cisplatin. Cisplatin + rikkunshito, a serotonin 2C receptor antagonist or serotonin 3 receptor antagonist, was investigated. The effects of intracerebroventricular (icv) administration of ghrelin or the serotonin 2C receptor antagonist SB242084 on food intake were also evaluated in cisplatin-treated rats. Hypothalamic ghrelin secretion significantly increased in 24-h-fasted rats compared to freely fed rats and was markedly reduced 24 and 48 h after cisplatin treatment in cisplatin-treated rats compared to saline-treated rats, although their plasma ghrelin levels were comparable. In cisplatin-treated rats, icv ghrelin administration reversed the decrease in food intake, vagotomy partially restored hypothalamic ghrelin secretion, and hypothalamic serotonin 2C receptor mRNA expression increased significantly. Administration of rikkunshito (an endogenous ghrelin enhancer) or a serotonin 2C receptor antagonist reversed the decrease in hypothalamic ghrelin secretion and food intake 24 h after cisplatin treatment. Cisplatin-induced anorexia is mediated through reduced hypothalamic ghrelin secretion. Cerebral serotonin 2C receptor activation partially induces decrease in hypothalamic ghrelin secretion, and rikkunshito suppresses cisplatin-induced anorexia by enhancing this secretion.

  13. Helicobacter pylori infection is associated with increased expression of macrophage migration inhibitory factor by T cells and macrophages in gastric mucosa

    Institute of Scientific and Technical Information of China (English)

    HE Xing Xiang; Harry Hua Xiang XIA; ZHAO Ying Heng; LIN Man Peng; SHEN Qing Yan; LIU Wei; ZHENG Xue Ling

    2004-01-01

    AIM Macrophage migration inhibitory factor (MIF) plays a pivotal role in inflammatory/immune diseases.This study aimed to determine MIF expression in H.pylori-induced gastritis,and the effect of H.pylori on MIF expression in monocytes in vitro.METHODS Seventy-nine patients (M/F,39/40,mean age,52 yrs) referred for upper endoscopy were selected;19 with gastric ulcer,15 with duodenal ulcer and 45 with non-ulcer dyspepsia (NUD).Gastric antral and body biopsies were obtained for histological examinations,double immunostaining for MIF/T-cells (CD45RO) and MIF/macrophage (KP1),and in situ hybridization for the expression of MIF mRNA.THp-1,a monocyte cell line,was co-incubated with different concentrations of the whole cell proteins prepared from H.pylori strain ATCC26695 or its isogenic type with cagA gene deleted.The expression of MIF protein was determined by using enzyme linked immunosorbent assay and the MIF mRNA by retrospective transcription-polymerase chain reaction techniques.RESULTS H.pylori was detected in 50 patients (10 with gastric ulcer, 15 with duodenal ulcer and 25 with NUD).Overall,the numbers of total T-cells,MIF+T-cells,total macrophages,MIF+macrophages and MIF mRNA+ cells were greater in the gastric antrum than in the body.There was a significant increase in the numbers of total T-cells, MIF+ T-cells,total macrophages,MIF+macrophages and MIF mRNA+cells in H. pylori positive,compared with H.pylori negative patients,in both the antral and body mucosa.Moreover,the cell numbers increased with more severe chronic gastritis in both the antrum and body.The numbers were also significantly higher in ulcer patients than in NUD patients, particularly in H. pylori positive patients.In vitro,the expression of MIF protein and mRNA in monocytes was significantly increased by incubation with H.pylori whole cell proteins,in a time and dose dependent manner.CONCLUSIONS H.pylori infection stimulates the expression of MIF in the gastric inflammatory cells,which may play a

  14. G protein-coupled receptor 120 signaling regulates ghrelin secretion in vivo and in vitro.

    Science.gov (United States)

    Gong, Zhi; Yoshimura, Makoto; Aizawa, Sayaka; Kurotani, Reiko; Zigman, Jeffrey M; Sakai, Takafumi; Sakata, Ichiro

    2014-01-01

    Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor, is produced predominantly in the stomach. It has been reported that endogenous ghrelin levels are increased by fasting and decreased immediately after feeding and that fasting-induced ghrelin release is controlled by the sympathetic nervous system. However, the mechanisms of plasma ghrelin decrement after feeding are poorly understood. Here, we studied the control of ghrelin secretion using ghrelin-producing cell lines and found that these cells express high levels of mRNA encoding G-protein coupled receptor 120 (GPR120). Addition of GW-9508 (a GPR120 chemical agonist) and α-linolenic acid (a natural ligand for GPR120) inhibited the secretion of ghrelin by ∼50 and 70%, respectively. However, the expression levels of preproghrelin and ghrelin O-acyltransferase (GOAT) mRNAs were not influenced by GW-9508. In contrast, the expression levels of prohormone convertase 1 were decreased significantly by GW-9508 incubation. Moreover, we observed that the inhibitory effect of GW-9508 on ghrelin secretion was blocked by a small interfering RNA (siRNA) targeting the sequence of GPR120. Furthermore, pretreatment with GW-9508 blocked the effect of the norepinephrine (NE)-induced ghrelin elevation in ghrelin cell lines. In addition, we showed that GW-9508 inhibited ghrelin secretion via extracellular signal-regulated kinase activity in ghrelin cell lines. Finally, we found that GW-9508 decreased plasma ghrelin levels in mice. These results suggest that the decrease of ghrelin secretion after feeding is induced partially by long-chain fatty acids that act directly on gastric GPR120-expressing ghrelin cells.

  15. Obesity, food intake and exercise: Relationship with ghrelin

    National Research Council Canada - National Science Library

    Gul Tiryaki-Sonmez; Serife Vatansever; Burcin Olcucu; Brad Schoenfeld

    2015-01-01

    ... – and long-term energy homeostasis. In the presence of increased obesity, decreased physical activity, and high food consumption, the relationship between exercise, appetite, food intake and ghrelin levels has important implications. In this review, we discuss the effect of acute and chronic exercise performance on appetite, food intake and ghrelin and their relationships.

  16. Ghrelin receptor regulates adipose tissue inflammation in aging

    Science.gov (United States)

    Aging is commonly associated with low-grade adipose inflammation, which is closely linked to insulin resistance. Ghrelin is the only circulating orexigenic hormone which is known to increase obesity and insulin resistance. We previously reported that the expression of the ghrelin receptor, growth ho...

  17. The Leu7Pro polymorphism of preproNPY is associated with decreased insulin secretion, delayed ghrelin suppression, and increased cardiovascular responsiveness to norepinephrine during oral glucose tolerance test.

    Science.gov (United States)

    Jaakkola, Ulriikka; Kuusela, Tom; Jartti, Tuomas; Pesonen, Ullamari; Koulu, Markku; Vahlberg, Tero; Kallio, Jaana

    2005-06-01

    Neuropeptide Y (NPY) plays a role in angiogenesis, cardiovascular regulation, and hormone secretion. The leucine7 to proline7 (Leu7Pro) polymorphism of preproNPY is associated with vascular diseases and has an impact on hormone levels in healthy subjects. The current study investigated the role of the Leu7Pro polymorphism in metabolic and cardiovascular autonomic regulation. A 5-h oral glucose tolerance test was performed on 27 healthy volunteers representing two preproNPY genotypes (Leu7/Pro7 and Leu7/Leu7) matched for age, sex, body mass index and physical activity. Simultaneously we performed cardiovascular autonomic function tests and plasma measurements of sympathetic transmitters, glucose, insulin, and ghrelin. The subjects with Leu7/Pro7 genotype had decreased plasma NPY, norepinephrine (NE), and insulin concentrations and insulin to glucose ratios. The suppression of ghrelin concentrations after glucose ingestion was delayed in these subjects. They also had increased heart rate variability indices and baroreflex sensitivity. However, they displayed significant negative association of NE concentration with variability of low-frequency R-R-intervals and with baroreflex sensitivity. The Leu7Pro polymorphism of preproNPY is related to decreased level of basal sympathetic activity, decreased insulin secretion, and delayed ghrelin suppression during oral glucose tolerance test. The increased responsiveness of autonomic functions to NE associated with the polymorphism may be connected to increased cardiovascular vulnerability.

  18. Ghrelin and cancer.

    Science.gov (United States)

    Chopin, Lisa; Walpole, Carina; Seim, Inge; Cunningham, Peter; Murray, Rachael; Whiteside, Eliza; Josh, Peter; Herington, Adrian

    2011-06-20

    Ghrelin is a peptide hormone that was originally isolated from the stomach as the endogenous ligand for the growth hormone secretagogue receptor (GHSR). Ghrelin has many functions, including the regulation of appetite and gut motility, growth hormone release from the anterior pituitary and roles in the cardiovascular and immune systems. Ghrelin and its receptor are expressed in a number of cancers and cancer cell lines and may play a role in processes associated with cancer progression, including cell proliferation, apoptosis, and cell invasion and migration.

  19. Is really endogenous ghrelin a hunger signal in chickens? Association of GHSR SNPs with increase appetite, growth traits, expression and serum level of GHRL, and GH.

    Science.gov (United States)

    El-Magd, Mohammed Abu; Saleh, Ayman A; Abdel-Hamid, Tamer M; Saleh, Rasha M; Afifi, Mohammed A

    2016-10-01

    Chicken growth hormone secretagogue receptor (GHSR) is a receptor for ghrelin (GHRL), a peptide hormone produced by chicken proventriculus, which stimulates growth hormone (GH) release and food intake. The purpose of this study was to search for single nucleotide polymorphisms (SNPs) in exon 2 of GHSR gene and to analyze their effect on the appetite, growth traits and expression levels of GHSR, GHRL, and GH genes as well as serum levels of GH and GHRL in Mandara chicken. Two adjacent SNPs, A239G and G244A, were detected in exon 2 of GHSR gene. G244A SNP was non-synonymous mutation and led to replacement of lysine amino acid (aa) by arginine aa, while A239G SNP was synonymous mutation. The combined genotypes of A239G and G244A SNPs produced three haplotypes; GG/GG, GG/AG, AG/AG, which associated significantly (P4 to 16w. Chickens with the homozygous GG/GG haplotype showed higher growth performance than other chickens. The two SNPs were also correlated with mRNA levels of GHSR and GH (in pituitary gland), and GHRL (in proventriculus and hypothalamus) as well as with serum level of GH and GHRL. Also, chickens with GG/GG haplotype showed higher mRNA and serum levels. This is the first study to demonstrate that SNPs in GHSR can increase appetite, growth traits, expression and level of GHRL, suggesting a hunger signal role for endogenous GHRL.

  20. Effects of ghrelin on anorexia in tumor-bearing mice with eicosanoid-related cachexia.

    Science.gov (United States)

    Wang, Wenhua; Andersson, Marianne; Iresjö, Britt-Marie; Lönnroth, Christina; Lundholm, Kent

    2006-06-01

    Ghrelin is a novel brain-gut peptide that stimulates food intake and may secondarily increase body weight via a growth hormone secretagogue receptor (GHS-R). Tumor-bearing mice (MCG101), characterized by anorexia, fat loss and muscle wasting due to increased concentration of PGE2 and proinflammatory cytokines (IL-1beta, IL-6, TNF-alpha), were provided ghrelin i.p. at a low (20 microg/day) and high dose (40 microg/day) to examine the ability of ghrelin to counteract tumor-induced anorexia. Immunohistochemical staining and Western blot analyses were used to identify GHS-R expression in the brain as well as its relationship to NPY expression in hypothalamic neurons. GHS-R mRNA in hypothalamus and ghrelin mRNA in gastric fundus were quantified by RT-PCR. Body composition was determined by carcass extractions. GHS-R expression in hypothalamus and plasma ghrelin levels were significantly increased in freely-fed tumor-bearing mice, while gastric fundus expression of ghrelin was unaltered compared to non-tumor-bearing mice (controls). Ghrelin treatment increased food intake, body weight and whole body fat at both low and high doses of ghrelin in normal controls, while tumor-bearing mice showed improved intake and body composition at the high dose of ghrelin only. Exogenous ghrelin normalized the GHS-R expression in hypothalamus from tumor-bearing mice without alterations in the gastric fundus expression of ghrelin. Tumor growth was not altered by exogenous ghrelin. Our results indicate that MCG 101-bearing mice became ghrelin resistant despite upregulation of hypothalamic GHS-R expression, which confirms similar indirect observations in cancer patients. Thus, other factors downstream of the ghrelin-GHS-R system appear to be more important than ghrelin to explain cancer-induced anorexia.

  1. Molecular evolution of GPCRs: Ghrelin/ghrelin receptors.

    Science.gov (United States)

    Kaiya, Hiroyuki; Kangawa, Kenji; Miyazato, Mikiya

    2014-06-01

    After the discovery in 1996 of the GH secretagogue-receptor type-1a (GHS-R1a) as an orphan G-protein coupled receptor, many research groups attempted to identify the endogenous ligand. Finally, Kojima and colleagues successfully isolated the peptide ligand from rat stomach extracts, determined its structure, and named it ghrelin. The GHS-R1a is now accepted to be the ghrelin receptor. The existence of the ghrelin system has been demonstrated in many animal classes through biochemical and molecular biological strategies as well as through genome projects. Our work, focused on identifying the ghrelin receptor and its ligand ghrelin in laboratory animals, particularly nonmammalian vertebrates, has provided new insights into the molecular evolution of the ghrelin receptor. In mammals, it is assumed that the ghrelin receptor evolution is in line with the plate tectonics theory. In contrast, the evolution of the ghrelin receptor in nonmammalian vertebrates differs from that of mammals: multiplicity of the ghrelin receptor isoforms is observed in nonmammalian vertebrates only. This multiplicity is due to genome duplication and polyploidization events that particularly occurred in Teleostei. Furthermore, it is likely that the evolution of the ghrelin receptor is distinct from that of its ligand, ghrelin, because only one ghrelin isoform has been detected in all species examined so far. In this review, we summarize current knowledge related to the molecular evolution of the ghrelin receptor in mammalian and nonmammalian vertebrates. © 2014 Society for Endocrinology.

  2. Synergistic action of gastrin and ghrelin on gastric acid secretion in rats.

    Science.gov (United States)

    Fukumoto, Kaori; Nakahara, Keiko; Katayama, Tetsuro; Miyazatao, Mikiya; Kangawa, Kenji; Murakami, Noboru

    2008-09-12

    Gastrin and ghrelin are secreted from G cells and X/A-like cells in the stomach, respectively, and respective hormones stimulate gastric acid secretion by acting through histamine and the vagus nerve. In this study, we examined the relationship between gastrin, ghrelin and gastric acid secretion in rats. Intravenous (iv) administration of 3 and 10 nmol of gastrin induced transient increases of ghrelin levels within 10 min in a dose-dependent manner. Double immunostaining for ghrelin and gastrin receptor revealed that a proportion of ghrelin cells possess gastrin receptors. Although (iv) administration of gastrin or ghrelin induced significant gastric acid secretion, simultaneous treatment with both hormones resulted in a synergistic, rather than additive, increase of gastric acid secretion. This synergistic increase was not observed in vagotomized rats. These results suggest that gastrin may directly stimulate ghrelin release from the stomach, and that both hormones may increase gastric acid secretion synergistically.

  3. Altered lipid and salt taste responsivity in ghrelin and GOAT null mice.

    Directory of Open Access Journals (Sweden)

    Huan Cai

    Full Text Available Taste perception plays an important role in regulating food preference, eating behavior and energy homeostasis. Taste perception is modulated by a variety of factors, including gastric hormones such as ghrelin. Ghrelin can regulate growth hormone release, food intake, adiposity, and energy metabolism. Octanoylation of ghrelin by ghrelin O-acyltransferase (GOAT is a specific post-translational modification which is essential for many biological activities of ghrelin. Ghrelin and GOAT are both widely expressed in many organs including the gustatory system. In the current study, overall metabolic profiles were assessed in wild-type (WT, ghrelin knockout (ghrelin(-/-, and GOAT knockout (GOAT(-/- mice. Ghrelin(-/- mice exhibited decreased food intake, increased plasma triglycerides and increased ketone bodies compared to WT mice while demonstrating WT-like body weight, fat composition and glucose control. In contrast GOAT(-/- mice exhibited reduced body weight, adiposity, resting glucose and insulin levels compared to WT mice. Brief access taste behavioral tests were performed to determine taste responsivity in WT, ghrelin(-/- and GOAT(-/- mice. Ghrelin and GOAT null mice possessed reduced lipid taste responsivity. Furthermore, we found that salty taste responsivity was attenuated in ghrelin(-/- mice, yet potentiated in GOAT(-/- mice compared to WT mice. Expression of the potential lipid taste regulators Cd36 and Gpr120 were reduced in the taste buds of ghrelin and GOAT null mice, while the salt-sensitive ENaC subunit was increased in GOAT(-/- mice compared with WT mice. The altered expression of Cd36, Gpr120 and ENaC may be responsible for the altered lipid and salt taste perception in ghrelin(-/- and GOAT(-/- mice. The data presented in the current study potentially implicates ghrelin signaling activity in the modulation of both lipid and salt taste modalities.

  4. Altered lipid and salt taste responsivity in ghrelin and GOAT null mice.

    Science.gov (United States)

    Cai, Huan; Cong, Wei-Na; Daimon, Caitlin M; Wang, Rui; Tschöp, Matthias H; Sévigny, Jean; Martin, Bronwen; Maudsley, Stuart

    2013-01-01

    Taste perception plays an important role in regulating food preference, eating behavior and energy homeostasis. Taste perception is modulated by a variety of factors, including gastric hormones such as ghrelin. Ghrelin can regulate growth hormone release, food intake, adiposity, and energy metabolism. Octanoylation of ghrelin by ghrelin O-acyltransferase (GOAT) is a specific post-translational modification which is essential for many biological activities of ghrelin. Ghrelin and GOAT are both widely expressed in many organs including the gustatory system. In the current study, overall metabolic profiles were assessed in wild-type (WT), ghrelin knockout (ghrelin(-/-)), and GOAT knockout (GOAT(-/-)) mice. Ghrelin(-/-) mice exhibited decreased food intake, increased plasma triglycerides and increased ketone bodies compared to WT mice while demonstrating WT-like body weight, fat composition and glucose control. In contrast GOAT(-/-) mice exhibited reduced body weight, adiposity, resting glucose and insulin levels compared to WT mice. Brief access taste behavioral tests were performed to determine taste responsivity in WT, ghrelin(-/-) and GOAT(-/-) mice. Ghrelin and GOAT null mice possessed reduced lipid taste responsivity. Furthermore, we found that salty taste responsivity was attenuated in ghrelin(-/-) mice, yet potentiated in GOAT(-/-) mice compared to WT mice. Expression of the potential lipid taste regulators Cd36 and Gpr120 were reduced in the taste buds of ghrelin and GOAT null mice, while the salt-sensitive ENaC subunit was increased in GOAT(-/-) mice compared with WT mice. The altered expression of Cd36, Gpr120 and ENaC may be responsible for the altered lipid and salt taste perception in ghrelin(-/-) and GOAT(-/-) mice. The data presented in the current study potentially implicates ghrelin signaling activity in the modulation of both lipid and salt taste modalities.

  5. Increasing metronidazole and rifampicin resistance of Helicobacter pylori isolates obtained from children and adolescents between 2002 and 2015 in southwest Germany.

    Science.gov (United States)

    Regnath, Thomas; Raecke, Olaf; Enninger, Axel; Ignatius, Ralf

    2017-02-01

    Increasing antibiotic resistance has been reported for Helicobacter pylori, but data on the prevalence of antibiotic resistance of H. pylori in pediatric patients and the development of resistance over time are sparse. Data for 610 H. pylori isolates obtained between 2002 and 2015 from gastric biopsies of 582 (mainly treatment-naïve) pediatric patients from southwest Germany were analyzed retrospectively regarding the antibiotic susceptibility determined by Etest and patients' characteristics. Overall resistance to metronidazole, clarithromycin, and rifampicin was 28.7%, 23.2%, and 13.3%, respectively, while resistance to amoxicillin was rare (0.8%). Simultaneous resistance to metronidazole and clarithromycin was observed for 7.7% of the isolates, and 2.3% were resistant to metronidazole, clarithromycin, and rifampicin. Differences between primary vs secondary resistance existed for metronidazole (24.7% vs 38.8%, P=.01) and clarithromycin (17.2% vs 54.1%, P=.0001). From 2002-2008 to 2009-2015, resistance to metronidazole increased from 20.8% to 34.4% (P=.003) and to rifampicin from 3.9% to 18.8% (P=.0001); this was not associated with increased numbers of patients previously treated for H. pylori infection in the second study period. In contrast, resistance to clarithromycin did not change significantly over time. Resistance was not associated with age, sex, or family origin in Europe. The considerable antibiotic resistance of H. pylori isolates argues for standard antibiotic susceptibility testing of H. pylori in pediatric patients prior to the initiation of antibiotic therapy. © 2016 John Wiley & Sons Ltd.

  6. Ghrelin and eating disorders

    National Research Council Canada - National Science Library

    Fabbri, Alessandra Donzelli; Deram, Sophie; Kerr, Daniel Shikanai; Cordás, Táki Athanássios

    2015-01-01

    ...; we searched PubMed, Scientific Electronic Library Online (SciELO), and LILACS databases using the keywords "eating disorder", "ghrelin", "polymorphism", "anorexia nervosa", "bulimia nervosa", "binge eating disorder", and their combinations...

  7. Mathematical Model for Hemodynamicand Hormonal Effects of Human Ghrelin in Healthy Volunteers

    Directory of Open Access Journals (Sweden)

    Geetha.T

    2014-11-01

    Full Text Available Hemodynamicand hormonal effects of human ghrelin in healthy volunteers.To investigate hemodynamic and hormonaleffects of ghrelin, a novel growth hormone (GH-releasing peptide, we gave six healthy men an intravenousbolus of human ghrelin or placebo and vice versa1–2 wk apart in a randomized fashion. Ghrelin elicited amarked increase in circulating GH . The elevation ofGH lasted longer than 60 min after the bolus injection.Injection of ghrelin significantly decreased mean arterialpressure without a significant changein heart rate .In summary, human ghrelin elicited a potent, longlastingGH release and had beneficial hemodynamic effectsvia reducing cardiac afterload and increasing cardiac outputwithout an increase in heart rate. Thus, the purpose of thisstudy was to investigate hemodynamic and hormonaleffects of intravenous ghrelin in healthy volunteers. This paper discussed the constant stress level of healthy volunteers with times to damage of stress effect andrecoveries

  8. Chronic Renal Failure, Cachexia, and Ghrelin

    Directory of Open Access Journals (Sweden)

    A. Laviano

    2010-01-01

    Full Text Available Protein energy wasting is frequently observed in patients with advanced chronic renal failure and end-stage renal disease. Anorexia and reduced food intake are critical contributing factors and negatively impact on patients' survival. Ghrelin is a prophagic peptide produced by the stomach and acting at the hypothalamic level to increase the activity of orexigenic neurons. In patients with chronic renal disease, plasma levels are increased as a likely effect of reduced renal clearance. Nevertheless, patients' food intake is significantly reduced, suggesting inflammation-mediated resistance of hypothalamic nuclei to peripheral signals. A number of forms of evidence show that ghrelin resistance could be overcome by the administration of exogenous ghrelin. Therefore, ghrelin has been proposed as a potential strategy to improve food intake in chronic renal failure patients with protein energy wasting. Preliminary data are encouraging although larger prospective clinical trials are needed to confirm the results and to identify those patients who are likely to benefit most from the administration of exogenous ghrelin.

  9. Chronic renal failure, cachexia, and ghrelin.

    Science.gov (United States)

    Laviano, A; Krznaric, Z; Sanchez-Lara, K; Preziosa, I; Cascino, A; Rossi Fanelli, F

    2010-01-01

    Protein energy wasting is frequently observed in patients with advanced chronic renal failure and end-stage renal disease. Anorexia and reduced food intake are critical contributing factors and negatively impact on patients' survival. Ghrelin is a prophagic peptide produced by the stomach and acting at the hypothalamic level to increase the activity of orexigenic neurons. In patients with chronic renal disease, plasma levels are increased as a likely effect of reduced renal clearance. Nevertheless, patients' food intake is significantly reduced, suggesting inflammation-mediated resistance of hypothalamic nuclei to peripheral signals. A number of forms of evidence show that ghrelin resistance could be overcome by the administration of exogenous ghrelin. Therefore, ghrelin has been proposed as a potential strategy to improve food intake in chronic renal failure patients with protein energy wasting. Preliminary data are encouraging although larger prospective clinical trials are needed to confirm the results and to identify those patients who are likely to benefit most from the administration of exogenous ghrelin.

  10. Effect of ghrelin on inflammatory response in lung contusion.

    Science.gov (United States)

    Guven, Berrak; Gokce, Mertol; Saydam, Ozkan; Can, Murat; Bektas, Sibel; Yurtlu, Serhan

    2013-02-01

    The purpose of this study was to investigate the effects of ghrelin on inflammatory response and tissue damage following trauma-induced acute lung injury. Thirty male wistar albino rats (300-400 g) were randomly assigned into three groups: control group (n = 6), lung contusion plus saline (saline-treated, n = 12), and lung contusion plus ghrelin (ghrelin-treated, n = 12). Saline- or ghrelin-treated traumatic rats were sacrificed at two time points (24 and 72 hours) after lung contusion. Blood was collected for the analysis of serum adenosine deaminase (ADA). Tissue transforming growth factor-beta 1 (TGF-β1) and matrix metalloproteinase-2 (MMP-2) levels were measured by enzyme-linked immunosorbent assay and histopathological examination was performed on the lung tissue samples. Our results indicated that ghrelin significantly reduced morphologic damages. Serum ADA activities were significantly decreased after lung contusion and this decline started early with ghrelin treatment. TGF-β1 and MMP-2 levels in lung tissue were elevated at 72 hours after lung contusion and treatment with ghrelin significantly increased TGF-β1 level and reduced MMP-2 level. In conclusion, our study demonstrates that acute lung injury initiated proinflammatory responses and ghrelin administration showed an anti-inflammatory effect in lung contusion.

  11. Ghrelin receptors mediate ghrelin-induced excitation of agouti-related protein/neuropeptide Y but not pro-opiomelanocortin neurons.

    Science.gov (United States)

    Chen, Shao-Rui; Chen, Hong; Zhou, Jing-Jing; Pradhan, Geetali; Sun, Yuxiang; Pan, Hui-Lin; Li, De-Pei

    2017-08-01

    Ghrelin increases food intake and body weight by stimulating orexigenic agouti-related protein (AgRP)/neuropeptide Y (NPY) neurons and inhibiting anorexic pro-opiomelanocortin (POMC) neurons in the hypothalamus. Growth hormone secretagogue receptor (Ghsr) mediates the effect of ghrelin on feeding behavior and energy homeostasis. However, the role of Ghsr in the ghrelin effect on these two populations of neurons is unclear. We hypothesized that Ghsr mediates the effect of ghrelin on AgRP and POMC neurons. In this study, we determined whether Ghsr similarly mediates the effects of ghrelin on AgRP/NPY and POMC neurons using cell type-specific Ghsr-knockout mice. Perforated whole-cell recordings were performed on green fluorescent protein-tagged AgRP/NPY and POMC neurons in the arcuate nucleus in hypothalamic slices. In Ghsr(+/+) mice, ghrelin (100 nM) significantly increased the firing activity of AgRP/NPY neurons but inhibited the firing activity of POMC neurons. In Ghsr(-/-) mice, the excitatory effect of ghrelin on AgRP/NPY neurons was abolished. Ablation of Ghsr also eliminated ghrelin-induced increases in the frequency of GABAergic inhibitory postsynaptic currents of POMC neurons. Strikingly, ablation of Ghsr converted the ghrelin effect on POMC neurons from inhibition to excitation. Des-acylated ghrelin had no such effect on POMC neurons in Ghsr(-/-) mice. In both Ghsr(+/+) and Ghsr(-/-) mice, blocking GABAA receptors with gabazine increased the basal firing activity of POMC neurons, and ghrelin further increased the firing activity of POMC neurons in the presence of gabazine. Our findings provide unequivocal evidence that Ghsr is essential for ghrelin-induced excitation of AgRP/NPY neurons. However, ghrelin excites POMC neurons through an unidentified mechanism that is distinct from conventional Ghsr. © 2017 International Society for Neurochemistry.

  12. Postprandial inhibition of gastric ghrelin secretion by long-chain fatty acid through GPR120 in isolated gastric ghrelin cells and mice.

    Science.gov (United States)

    Lu, Xinping; Zhao, Xilin; Feng, Jianying; Liou, Alice P; Anthony, Shari; Pechhold, Susanne; Sun, Yuxiang; Lu, Huiyan; Wank, Stephen

    2012-08-01

    Ghrelin is a gastric peptide hormone that controls appetite and energy homeostasis. Plasma ghrelin levels rise before a meal and fall quickly thereafter. Elucidation of the regulation of ghrelin secretion has been hampered by the difficulty of directly interrogating ghrelin cells diffusely scattered within the complex gastric mucosa. Therefore, we generated transgenic mice with ghrelin cell expression of green fluorescent protein (GFP) to enable characterization of ghrelin secretion in a pure population of isolated gastric ghrelin-expressing GFP (Ghr-GFP) cells. Using quantitative RT-PCR and immunofluorescence staining, we detected a high level of expression of the long-chain fatty acid (LCFA) receptor GPR120, while the other LCFA receptor, GPR40, was undetectable. In short-term-cultured pure Ghr-GFP cells, the LCFAs docosadienoic acid, linolenic acid, and palmitoleic acid significantly suppressed ghrelin secretion. The physiological mechanism of LCFA inhibition on ghrelin secretion was studied in mice. Serum ghrelin levels were transiently suppressed after gastric gavage of LCFA-rich lipid in mice with pylorus ligation, indicating that the ghrelin cell may directly sense increased gastric LCFA derived from ingested intraluminal lipids. Meal-induced increase in gastric mucosal LCFA was assessed by measuring the transcripts of markers for tissue uptake of LCFA, lipoprotein lipase (LPL), fatty acid translocase (CD36), glycosylphosphatidylinositol-anchored HDL-binding protein 1, and nuclear fatty acid receptor peroxisome proliferator-activated receptor-γ. Quantitative RT-PCR studies indicate significantly increased mRNA levels of lipoprotein lipase, glycosylphosphatidylinositol-anchored HDL-binding protein 1, and peroxisome proliferator-activated receptor-γ in postprandial gastric mucosa. These results suggest that meal-related increases in gastric mucosal LCFA interact with GPR120 on ghrelin cells to inhibit ghrelin secretion.

  13. Novel regulator of acylated ghrelin, CF801, reduces weight gain, rebound feeding after a fast, and adiposity in mice

    Directory of Open Access Journals (Sweden)

    Martin K Wellman

    2015-09-01

    Full Text Available Ghrelin is a 28 amino-acid hormonal peptide that is intimately related to the regulation of food intake and body weight. Once secreted, ghrelin binds to the growth hormone secretagogue receptor-1a (GHSR-1a, the only known receptor for ghrelin and is capable of activating a number of signaling cascades ultimately resulting in an increase in food intake and adiposity. Because ghrelin has been linked to overeating and the development of obesity, a number of pharmacological interventions have been generated in order to interfere with either the activation of ghrelin or interrupting ghrelin signaling as a means to reducing appetite and decrease weight gain. Here we present a novel peptide, CF801, capable of reducing circulating acylated ghrelin levels and subsequent body weight gain and adiposity. To this end, we show that IP administration of CF801 is sufficient to reduce circulating plasma acylated ghrelin levels. Acutely, intraperitoneal injections of CF801 resulted in decreased rebound feeding after an overnight fast. When delivered chronically decreased weight gain and adiposity without affecting caloric intake. CF801, however, did cause a change in diet preference, decreasing preference for a high fat diet and increasing preference for regular chow diet. Given the complexity of ghrelin receptor function, we propose that CF801 along with other compounds that regulate ghrelin secretion may prove to be a beneficial tool in the study of the ghrelin system, and potential targets for ghrelin based obesity treatments without altering the function of ghrelin receptors.

  14. Estimation of gastric ghrelin-positive cells activity in hyperthyroid rats.

    Directory of Open Access Journals (Sweden)

    Maria M Winnicka

    2009-01-01

    Full Text Available Ghrelin is a peptide of 28 amino acids that transmits appetite related signals from peripheral organs to the brain. The main source of ghrelin is stomach. The regulation of ghrelin secretion is still unknown. The finding that fasting and food intake, respectively increase and decrease the secretion of ghrelin suggests that this hormone may be a bridge connecting somatic growth with energy metabolism and appears to play an important role in the alteration of energy homeostasis and body weight in pathophisiological conditions. The purpose of this study was the evaluation of gastric ghrelin immunoreactivity and ghrelin plasma concentration in male Wistar rats with hyperthyroidism. Experimental model of hyperthyroidism was induced by intraperitoneal injection of levothyroxine at the dose of 80 microg/kg daily over 21 days. At the end of experiment the animals were anaesthetized, blood was taken from abdominal aorta to determinate plasma ghrelin concentration by RIA and then the animals underwent resection of distal part of stomach. Immunohistochemical study were performed using monoclonal specific antybodies against ghrelin. Hyperthyroidism was a reason of increase of gastric mucosal ghrelin - immunoreactivity, accompanied by a significant decreased of ghrelin plasma concentration. Those observations may indicate, that chronic administration of L-thyroxine cause the change of ghrelin plasma concentration in rats, probably via direct influence on gastric X/A-like cells, but this effect is not responsible for hyperphagia associated with hyperthyroidism.

  15. The increasing prevalence of HIV/Helicobacter pylori co-infection over time, along with the evolution of antiretroviral therapy (ART).

    Science.gov (United States)

    Radovanović Spurnić, Aleksandra; Brmbolić, Branko; Stojšić, Zorica; Pekmezović, Tatijana; Bukumirić, Zoran; Korać, Miloš; Salemović, Dubravka; Pešić-Pavlović, Ivana; Stevanović, Goran; Milošević, Ivana; Jevtović, Djordje

    2017-01-01

    Helicobacter pylori (H. pylori) is one of the most common human bacterial infections with prevalence rates between 10-80% depending upon geographical location, age and socioeconomic status. H. pylori is commonly found in patients complaining of dyspepsia and is a common cause of gastritis. During the course of their infection, people living with HIV (PLHIV) often have a variety of gastrointestinal symptoms including dyspepsia and while previous studies have reported HIV and H. pylori co-infection, there has been little data clarifying the factors influencing this. The aim of this case-control study was to document the prevalence of H. pylori co-infection within the HIV community as well as to describe endoscopic findings, gastritis topography and histology, along with patient demographic characteristics across three different periods of time during which antiretroviral therapy (ART) has evolved, from pre- highly active antiretroviral therapy (HAART) to early and modern HAART eras. These data were compared to well-matched HIV negative controls. Two hundred and twelve PLHIV were compared with 1,617 controls who underwent their first esophagogastroduodenoscopy (EGD) to investigate dyspepsia. The prevalence of H. pylori co-infection among PLHIV was significantly higher in the early (30.2%) and modern HAART period (34.4%) compared with those with coinfection from the pre-HAART period (18.2%). The higher rates seen in patients from the HAART eras were similar to those observed among HIV negative controls (38.5%). This prevalence increase among co-infected patients was in contrast to the fall in prevalence observed among controls, from 60.7% in the early period to 52.9% in the second observed period. The three PLHIV co-infected subgroups differed regarding gastritis topography, morphology and pathology. This study suggests that ART has an important impact on the endoscopic and histological features of gastritis among HIV/H. pylori co-infected individuals, raising the

  16. Role of Helicobacter pylori infection on nutrition and metabolism

    Science.gov (United States)

    Franceschi, Francesco; Annalisa, Tortora; Teresa, Di Rienzo; Giovanna, D’Angelo; Ianiro, Gianluca; Franco, Scaldaferri; Viviana, Gerardi; Valentina, Tesori; Riccardo, Lopetuso Loris; Antonio, Gasbarrini

    2014-01-01

    Helicobacter pylori (H. pylori) is a gram-negative pathogen that is widespread all over the world, infecting more than 50% of the world’s population. It is etiologically associated with non-atrophic and atrophic gastritis, peptic ulcer and shows a deep association with primary gastric B-cell lymphoma and gastric adenocarcinoma. Recently, the medical research focused on the modification of the gastric environment induced by H. pylori infection, possibly affecting the absorption of nutrients and drugs as well as the production of hormones strongly implicated in the regulation of appetite and growth. Interestingly, the absorption of iron and vitamin B12 is impaired by H. pylori infection, while infected subjects have lower basal and fasting serum levels of ghrelin and higher concentration of leptin compared to controls. Since leptin is an anorexigenic hormone, and ghrelin stimulates powerfully the release of growth hormone in humans, H. pylori infection may finally induce growth retardation if acquired very early in the childhood and in malnourished children. This review is focused on the nutritional effects of H. pylori infection, such as the reduced bioavailability or the malabsorbption of essential nutrients, and of gastrointestinal hormones, as well as on the relationship between H. pylori and the metabolic syndrome. PMID:25278679

  17. Insulin and norepinephrine regulate ghrelin secretion from a rat primary stomach cell culture.

    Science.gov (United States)

    Gagnon, Jeffrey; Anini, Younes

    2012-08-01

    Ghrelin is a peptide hormone primarily produced in the previously unidentified X/A endocrine cells of the stomach. Extensive studies have focused on the effects of ghrelin on growth hormone release and appetite regulation. However, the mechanisms regulating ghrelin secretion are less understood. In the present study, we developed a primary culture of newborn rat stomach cells to investigate the mechanisms regulating ghrelin synthesis and secretion. We demonstrated that this cell preparation secretes ghrelin in a regulated manner through the increase of cAMP, intracellular calcium, and activation of protein kinase C. Norepinephrine (NE) (0.1-10 μm) stimulated ghrelin secretion through the β1-adrenergic receptor via increased cAMP and protein kinase A activity, whereas acetylcholine had no effect. Because circulating ghrelin levels were previously shown to be inversely correlated with insulin levels, we investigated the effect of insulin on ghrelin secretion. We first demonstrated that ghrelin cells express the insulin receptor α- and β-subunits. Next, we determined that insulin (1-10 nm) inhibited both basal and NE-stimulated ghrelin secretion, caused an increase in phosphorylated serine-threonine kinase (AKT) and a reduction in intracellular cAMP, but did not alter proghrelin mRNA levels. The inhibitory effect of insulin was blocked by inhibiting phospho-inositol-3 kinase and AKT but not MAPK. Higher dose insulin (100 nm) did not suppress ghrelin secretion, which prompted the investigation of cellular insulin resistance by pretreating the cells with 100 nm insulin for 24 h. This caused a reduction in insulin receptor expression and prevented the insulin-mediated AKT activation and the suppression of ghrelin secretion with no impact on NE-stimulated ghrelin secretion. Our findings highlight the role of the sympathetic nervous system, insulin, and insulin resistance in the regulation of ghrelin secretion.

  18. Helicobacter pylori

    DEFF Research Database (Denmark)

    Leth, Peter Mygind

    1992-01-01

    Helicobacter pylori (HP) are Gram-negative spiral bacteria which occur in the human stomach. The bacteria were cultured in vitro for the first time in 1983. It is suspected that the bacteria may cause chronic gastritis of type B and may also be a contributory cause of chronic ulceration and cancer...... of the stomach. The bacteria are accompanied by characteristic inflammatory changes in the gastric mucosa. The significance for gastritis, chronic ulceration, non-ulcer dyspepsia and carcinoma of the stomach is discussed. HP occurs in a great proportion of the population of the world and the frequency increases...

  19. Helicobacter pylori

    DEFF Research Database (Denmark)

    Leth, Peter Mygind

    1992-01-01

    of the stomach. The bacteria are accompanied by characteristic inflammatory changes in the gastric mucosa. The significance for gastritis, chronic ulceration, non-ulcer dyspepsia and carcinoma of the stomach is discussed. HP occurs in a great proportion of the population of the world and the frequency increases......Helicobacter pylori (HP) are Gram-negative spiral bacteria which occur in the human stomach. The bacteria were cultured in vitro for the first time in 1983. It is suspected that the bacteria may cause chronic gastritis of type B and may also be a contributory cause of chronic ulceration and cancer...

  20. Ghrelin promotes oral tumor cell proliferation by modifying GLUT1 expression.

    Science.gov (United States)

    Kraus, Dominik; Reckenbeil, Jan; Wenghoefer, Matthias; Stark, Helmut; Frentzen, Matthias; Allam, Jean-Pierre; Novak, Natalija; Frede, Stilla; Götz, Werner; Probstmeier, Rainer; Meyer, Rainer; Winter, Jochen

    2016-03-01

    In our study, ghrelin was investigated with respect to its capacity on proliferative effects and molecular correlations on oral tumor cells. The presence of all molecular components of the ghrelin system, i.e., ghrelin and its receptors, was analyzed and could be detected using real-time PCR and immunohistochemistry. To examine cellular effects caused by ghrelin and to clarify downstream-regulatory mechanisms, two different oral tumor cell lines (BHY and HN) were used in cell culture experiments. Stimulation of either cell line with ghrelin led to a significantly increased proliferation. Signal transduction occurred through phosphorylation of GSK-3β and nuclear translocation of β-catenin. This effect could be inhibited by blocking protein kinase A. Glucose transporter1 (GLUT1), as an important factor for delivering sufficient amounts of glucose to tumor cells having high requirements for this carbohydrate (Warburg effect) was up-regulated by exogenous and endogenous ghrelin. Silencing intracellular ghrelin concentrations using siRNA led to a significant decreased expression of GLUT1 and proliferation. In conclusion, our study describes the role for the appetite-stimulating peptide hormone ghrelin in oral cancer proliferation under the particular aspect of glucose uptake: (1) tumor cells are a source of ghrelin. (2) Ghrelin affects tumor cell proliferation through autocrine and/or paracrine activity. (3) Ghrelin modulates GLUT1 expression and thus indirectly enhances tumor cell proliferation. These findings are of major relevance, because glucose uptake is assumed to be a promising target for cancer treatment.

  1. The effect of ghrelin on cell proliferation in small intestinal IEC-6 cells.

    Science.gov (United States)

    Yu, Huafang; Xu, Guoxiong; Fan, Xiaoming

    2013-04-01

    Recent evidence demonstrates that ghrelin, a short orexigenic peptide from the stomach, has dual effects on cell proliferation in different cell types via autocrine and/or paracrine mechanisms. The aim of this study is to investigate the proliferative role of ghrelin in intestinal epithelial IEC-6 cells and explore underlying mechanism. RT-PCR was used for the detection of growth hormone secretagogue receptor 1a. Cell proliferation was measured using Cell Counting Kit-8. Protein expression of ERK 1/2 and Akt was examined using western blotting. Inhibitors of mitogen activated protein kinases kinase and phosphatidylinositol 3-kinase were used to evaluate the role of these signalling pathways in ghrelin-induced proliferation of IEC-6 cells. Growth hormone secretagogue receptor 1a mRNA was present in IEC-6 cells. Ghrelin and des-acyl ghrelin increased IEC-6 cell proliferation in a dose- and time-dependent manner. Ghrelin and des-acyl ghrelin activated ERK1/2, but not Akt. U0126, a specific inhibitor of mitogen activated protein kinases kinase, blocked ghrelin- and des-acyl ghrelin-induced ERK1/2 phosphorylation and cell proliferation in IEC-6 cells. Ghrelin and des-acyl ghrelin stimulate the proliferation of IEC-6 cells via the ERK1/2 pathway. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  2. Modulation of Ingestive Behavior and Gastrointestinal Motility by Ghrelin in Diabetic Animals and Humans

    Directory of Open Access Journals (Sweden)

    Chih-Yen Chen

    2010-05-01

    Full Text Available Acyl ghrelin, a 28-amino acid peptide hormone, is the endogenous cognate ligand for the growth hormone secretagogue receptor. Ghrelin is involved in stimulating growth hormone release, eliciting feeding behavior, inducing adiposity and stimulating gastrointestinal motility. Ghrelin is unique for its post-translational modification of O-n-octanoylation at serine 3 through ghrelin O-acyltransferase, and is the only peripheral signal to enhance food intake. Plasma ghrelin levels manifest “biphasic changes” in diabetes mellitus (DM. In the early stage of DM, the stomach significantly increases the secretion of ghrelin into the plasma, and elevated plasma ghrelin levels are correlated with diabetic hyperphagic feeding and accelerated gastrointestinal motility. In the late stage of DM, plasma ghrelin levels may be lower, which might be linked with anorexia/muscle wasting, delayed gastrointestinal transit, and even gastroparesis. Therefore, the unique ghrelin system may be the most important player compared to the other hindgut hormones participating in the “entero-insular axis”. Further studies using either knockdown or knockout of ghrelin gene products and ghrelin O-acyltransferase may unravel the pathogenesis of DM, and show benefits in combating this disease and metabolic syndrome.

  3. Influence of a long-term high-fat diet on ghrelin secretion and ghrelin-induced food intake in rats.

    Science.gov (United States)

    Gomez, Guillermo; Han, Song; Englander, Ella W; Greeley, George H

    2012-01-10

    The aims of this study were: (1) to define the extent to which a high-fat (HF) diet given on a long-term basis reduces resting plasma ghrelin (total [acyl+des-acyl]) levels and the plasma ghrelin (total) response to fasting, (2) to determine whether a chronic HF diet modifies the orexigenic activity of acyl-ghrelin, (3) whether insulin pretreatment inhibits the plasma ghrelin (total) response to fasting, and (4) the extent to which pioglitazone (PIO) treatment will increase stomach and plasma ghrelin (total) levels in rats fed a HF diet. PIO is a drug given to diabetics which improves insulin resistance. Our findings show that a chronic HF diet given for either 10 or 60 weeks exerts a persistent inhibitory effect on resting plasma ghrelin (total) levels. Additionally, the plasma ghrelin (total) elevation to overnight fasting is not altered in rats fed a HF diet on a long-term basis. A HF diet does not impair the ingestive response to acyl-ghrelin. Together, these results suggest that acyl-ghrelin serves as an important orexigenic factor. Results show that insulin pretreatment does not inhibit the plasma ghrelin (total) response to fasting suggesting that meal-induced insulin secretion does not have a role in reducing ghrelin (total) secretion. In rats fed a HF diet, PIO administration increases stomach ghrelin (total) levels. Because PIO can reduce systemic glucose and lipid levels, our findings suggest that elevated glucose and lipid levels are part of the inhibitory mechanism behind reduced ghrelin (total) secretion in rats fed a HF diet.

  4. Variable effect of ghrelin administration on pancreatic development in young rats. Role of insulin-like growth factor-1.

    Science.gov (United States)

    Dembiński, A; Warzecha, Z; Ceranowicz, P; Bielański, W; Cieszkowski, J; Dembiński, M; Pawlik, W W; Kuwahara, A; Kato, I; Konturek, P C

    2005-12-01

    Ghrelin, an endogenous ligand of the growth hormone secretagogue receptor, has been primarily isolated from the human and rat stomach. Ghrelin has been shown to stimulate appetite and fat deposition in adult rats and humans. The aim of this study was to investigate the effect of ghrelin administration on pancreatic growth in suckling, weaned and peripubertal seven week old rats. Rats were treated with saline or ghrelin (4, 8 or 16 nmol/kg/dose) intraperitoneally twice a day: suckling rats were treated for 7 or 14 days starting from the first postnatal day, three week old weaned rats and seven weeks old rats were treated for 5 days. Treatment with ghrelin did not affect animal weight in suckling or weaned rats, whereas in young seven week old rats, ghrelin caused a significant increase in body weight. Ghrelin decreased food intake in weaned rats; whereas in seven week old rats, food intake was enhanced. In suckling rats, ghrelin decreased the pancreatic weight, pancreatic amylase content, DNA synthesis and DNA content. In contrast, ghrelin increased pancreatic weight, DNA synthesis, DNA content and amylase content in weaned or young seven week old rats. Pancreatic blood flow was not affected by ghrelin in any group of rats tested. Ghrelin increased serum level of growth hormone in all rats. This effect was weak in suckling rats, higher in weaned and the highest in seven week old animals. Ghrelin did not affect serum level of insulin-like growth factor-1 (IGF-1) in suckling rats. In weaned and in seven week old rats, treatment with ghrelin caused increase in serum level of IGF-1. We conclude that ghrelin reduces pancreatic growth in suckling rats; whereas in weaned and young seven week old animals, treatment with ghrelin increases pancreatic growth. This biphasic effect of ghrelin in young animals on pancreatic growth seems to be related to age-dependent changes of the release of anabolic IGF-1.

  5. Ghrelin and eating disorders

    Directory of Open Access Journals (Sweden)

    Alessandra Donzelli Fabbri

    2015-04-01

    Full Text Available Background Ghrelin is a potent hormone with central and peripheral action. This hormone plays an important role in the regulation of appetite, food intake, and energy balance. Studies have suggested that ghrelin is involved with eating disorders (ED, particularly bingeing and purging. Genetic variants have also been studied to explain changes in eating behavior. Methods We conducted a literature review; we searched PubMed, Scientific Electronic Library Online (SciELO, and LILACS databases using the keywords “eating disorder”, “ghrelin”, “polymorphism”, “anorexia nervosa”, “bulimia nervosa”, “binge eating disorder”, and their combinations. We found 319 articles. Thirty-nine articles met the inclusion criteria. Results High levels of ghrelin were found in patients with anorexia nervosa (AN, especially in the purging subtype (AN-P. There was also a positive correlation between fasting ghrelin level and frequency of episodes of bingeing/purging in bulimia nervosa (BN and the frequency of bingeing in periodic binge eating disorder (BED. Some polymorphisms were associated with AN and BN. Conclusion Changes in ghrelin levels and its polymorphism may be involved in the pathogenesis of EDs; however, further studies should be conducted to clarify the associations.

  6. Helicobacter pylori Infection in Pediatrics.

    Science.gov (United States)

    Roma, Eleftheria; Miele, Erasmo

    2015-09-01

    This review includes the main pediatric studies published from April 2014 to March 2015. The host response of Treg cells with increases in FOXP3 and TGF-β1 combined with a reduction in IFN-γ by Teff cells may contribute to Helicobacter pylori susceptibility in children. Genotypic variability in H. pylori strains influences the clinical manifestation of the infection. Helicobacter pylori infection is associated with variables indicative of a crowded environment and poor living conditions, while breast-feeding has a protective effect. Intrafamilial infection, especially from mother to children and from sibling to sibling, is the dominant transmission route. Studies showed conflicting results regarding the association between H. pylori infection and iron deficiency anemia. One study suggests that H. pylori eradication plays a role in the management of chronic immune thrombocytopenic purpura in H. pylori-infected children and adolescents. The prevalence of H. pylori was higher in chronic urticaria patients than in controls and, following H. pylori eradication, urticarial symptoms disappeared. An inverse relationship between H. pylori infection and allergic disease was reported. Antibiotic resistance and insufficient compliance to treatment limit the efficacy of eradication therapy. Sequential therapy had no advantage over standard triple therapy. In countries where H. pylori infection is prevalent, studies focusing on virulence factors and antibiotic susceptibility may provide anticipation of the prognosis and may be helpful to reduce morbidity and mortality.

  7. Novel Regulator of Acylated Ghrelin, CF801, Reduces Weight Gain, Rebound Feeding after a Fast, and Adiposity in Mice

    OpenAIRE

    Martin K Wellman; Zachary Robert Patterson; Harry eMackay; Darling, Joseph E.; Mani, Bharath K.; Jeffrey eZigman; Hougland, James L.; Alfonso eAbizaid

    2015-01-01

    Ghrelin is a 28 amino acid hormonal peptide that is intimately related to the regulation of food intake and body weight. Once secreted, ghrelin binds to the growth hormone secretagogue receptor-1a, the only known receptor for ghrelin and is capable of activating a number of signaling cascades, ultimately resulting in an increase in food intake and adiposity. Because ghrelin has been linked to overeating and the development of obesity, a number of pharmacological interventions have been genera...

  8. Ghrelin and its therapeutic potential for cachectic patients.

    Science.gov (United States)

    Ashitani, Jun-ichi; Matsumoto, Nobuhiro; Nakazato, Masamitsu

    2009-10-01

    The discovery of ghrelin has resulted in the development of approaches to appetite, enabling a better understanding of the mechanisms regulating appetite through molecular analyses. Ghrelin is a 28-amino acid peptide that was isolated from the stomach only a decade ago, and has recently been investigated as a potential therapeutic endogenous agent. This peptide increases appetite, adjusts energy balance, suppresses inflammation, and enhances the release of growth hormone from the pituitary gland. Although many bioactive substances such as peptide YY, leptin, adiponectin and obestatin are involved in appetite control, ghrelin is the only known peptide to signal starvation information from a peripheral organ to the central nervous system, contributing to an increase in appetite. Clinical trials have revealed the effectiveness of ghrelin in increasing lean body mass and activity in cachectic patients. As shown in clinical research on humans and basic research using animal models, cachexia often occurs in response to excess release of proinflammatory cytokines and induces further appetite loss, which aggravates the physiological status of underlying diseases. Ghrelin functions as a protector against the vicious cycle of the cachectic paradigm through orexigenic, anabolic and anti-inflammatory effects, so administration of ghrelin may be able to improve quality of life in cachectic patients. We show here a significant role of ghrelin in the pathophysiology of cachectic diseases and the possibility of clinical applications.

  9. The pregnancy-induced increase in baseline circulating growth hormone in rats is not induced by ghrelin.

    Science.gov (United States)

    El-Kasti, M M; Christian, H C; Huerta-Ocampo, I; Stolbrink, M; Gill, S; Houston, P A; Davies, J S; Chilcott, J; Hill, N; Matthews, D R; Carter, D A; Wells, T

    2008-03-01

    The elevation in baseline circulating growth hormone (GH) that occurs in pregnant rats is thought to arise from increased pituitary GH secretion, but the underlying mechanism remains unclear. Distribution, Fourier and algorithmic analyses confirmed that the pregnancy-induced increase in circulating GH in 3-week pregnant rats was due to a 13-fold increase in baseline circulating GH (P hormone mRNA expression in the arcuate nuclei (P produce 'pituitary' GH. Although not excluding the possibility that the pregnancy-associated elevation in baseline circulating GH could arise from alternative extra-pituitary sources (e.g. the ovary), our data indicate that this phenomenon is most likely to result from a direct alteration of somatotroph function.

  10. Infection with Helicobacter pylori strains lacking dupA is associated with an increased risk of gastric ulcer and gastric cancer development.

    Science.gov (United States)

    Abadi, Amin Talebi Bezmin; Taghvaei, Tarang; Wolfram, Lutz; Kusters, Johannes G

    2012-01-01

    Recently, dupA was reported as a new virulence factor in Helicobacter pylori, but its association with gastroduodenal disorders and its mode of action are still unclear. Here, an association of the dupA status with different disease groups was determined and a biological explanation for the observed associations was tested. In total, 216 H. pylori isolates were obtained from 232 presumed H. pylori-infected patients. A positive association was observed between the occurrence of duodenal ulcer (DU) and the presence of dupA [odds ratio (OR) 24.2; 95 % confidence interval (CI) 10.6-54.8]. In addition, an inverse association between the occurrence of gastric cancer (GC) [OR 0.16; 95 % CI 0.05-0.47] and gastric ulcer (GU) [OR 0.34; 95 % CI 0.16-0.68] with the presence of dupA was observed. A putative explanation for the observed associations might be a more corpus-located infection (pan-gastritis) by the dupA-positive strains due to their increased acid resistance. Indeed, a strong association between dupA-positive H. pylori isolated from gastritis patients and in vitro acid resistance was observed (Prisk of DU formation, it also decreases the risk for the genesis of GUs and GC.

  11. MiR-27a rs895819 is involved in increased atrophic gastritis risk, improved gastric cancer prognosis and negative interaction with Helicobacter pylori

    Science.gov (United States)

    Xu, Qian; Chen, Tie-jun; He, Cai-yun; Sun, Li-ping; Liu, Jing-wei; Yuan, Yuan

    2017-01-01

    MiR-27a rs895819 is a loop-stem structure single nucleotide polymorphism affecting mature miR-27a function. In this study, we performed a comprehensive analysis about the association of rs895819 with gastric cancer risk and prognosis, atrophic gastritis risk, as well as the interactions with environmental factors. A total of 939 gastric cancer patients, 1,067 atrophic gastritis patients and 1,166 healthy controls were screened by direct sequencing and MALDI-TOF-MS. The association of rs895819 with clinical pathological parameters and prognostic survival in 357 gastric cancer patients was also been analyzed. The rs895819 variant genotype increased the risk for atrophic gastritis (1.58-fold) and gastric cancer (1.24-fold). While in stratified analysis, the risk effect was demonstrated more significantly in the female, age >60y, Helicobacter pylori (H. pylori) negative and non-drinker subgroups. Rs895819 and H. pylori showed an interaction effect for atrophic gastritis risk. In the survival analysis, the rs895819 AG heterozygosis was associated with better survival than the AA wild-type in the TNM stage I–II subgroup. In vitro study by overexpressing miR-27a, cells carrying polymorphic-type G allele expressed lower miR-27a than wild-type A allele. In conclusion, miR-27a rs895819 is implicated as a biomarker for gastric cancer and atrophic gastritis risk, and interacts with H. pylori in gastric carcinogenesis. PMID:28150722

  12. Diet-induced obesity causes ghrelin resistance in reward processing tasks.

    Science.gov (United States)

    Lockie, Sarah H; Dinan, Tara; Lawrence, Andrew J; Spencer, Sarah J; Andrews, Zane B

    2015-12-01

    Diet-induced obesity (DIO) causes ghrelin resistance in hypothalamic Agouti-related peptide (AgRP) neurons. However, ghrelin promotes feeding through actions at both the hypothalamus and mesolimbic dopamine reward pathways. Therefore, we hypothesized that DIO would also establish ghrelin resistance in the ventral tegmental area (VTA), a major site of dopaminergic cell bodies important in reward processing. We observed reduced sucrose and saccharin consumption in Ghrelin KO vs Ghrelin WT mice. Moreover, DIO reduced saccharin consumption relative to chow-fed controls. These data suggest that the deletion of ghrelin and high fat diet both cause anhedonia. To assess if these are causally related, we tested whether DIO caused ghrelin resistance in a classic model of drug reward, conditioned place preference (CPP). Chow or high fat diet (HFD) mice were conditioned with ghrelin (1mg/kg in 10ml/kg ip) in the presence or absence of food in the conditioning chamber. We observed a CPP to ghrelin in chow-fed mice but not in HFD-fed mice. HFD-fed mice still showed a CPP for cocaine (20mg/kg), indicating that they maintained the ability to develop conditioned behaviour. The absence of food availability during ghrelin conditioning sessions induced a conditioned place aversion, an effect that was still present in both chow and HFD mice. Bilateral intra-VTA ghrelin injection (0.33μg/μl in 0.5μl) robustly increased feeding in both chow-fed and high fat diet (HFD)-fed mice; however, this was correlated with body weight only in the chow-fed mice. Our results suggest that DIO causes ghrelin resistance albeit not directly in the VTA. We suggest there is impaired ghrelin sensitivity in upstream pathways regulating reward pathways, highlighting a functional role for ghrelin linking appropriate metabolic sensing with reward processing.

  13. A low-salt diet increases the expression of renal sirtuin 1 through activation of the ghrelin receptor in rats

    OpenAIRE

    Shao-Yu Yang; Shuei-Liong Lin; Yung-Ming Chen; Vin-Cent Wu; Wei-Shiung Yang; Kwan-Dun Wu

    2016-01-01

    Previous studies have shown that sirtuin 1 (Sirt1) is renoprotective; however, details regarding its distribution and functions in the kidney remain unknown. Here, we demonstrated that Sirt1 was mainly expressed in the tubulointerstitial cells of normal rat kidneys and was co-localized with aquaporin 2, indicating it may be involved in water/salt regulation. Renal Sirt1 expression increased in the non-glomerular cytoplasmic portion of the kidney after a 24-h fast, but no significant changes i...

  14. Ghrelin counteracts insulin-induced activation of vagal afferent neurons via growth hormone secretagogue receptor.

    Science.gov (United States)

    Iwasaki, Yusaku; Dezaki, Katsuya; Kumari, Parmila; Kakei, Masafumi; Yada, Toshihiko

    2015-08-01

    Vagal afferent nerves sense meal-related gastrointestinal and pancreatic hormones and convey their information to the brain, thereby regulating brain functions including feeding. We have recently demonstrated that postprandial insulin directly acts on the vagal afferent neurons. Plasma concentrations of orexigenic ghrelin and anorexigenic insulin show reciprocal dynamics before and after meals. The present study examined interactive effects of ghrelin and insulin on vagal afferent nerves. Cytosolic Ca(2+) concentration ([Ca(2+)]i) in isolated nodose ganglion (NG) neurons was measured to monitor their activity. Insulin at 10(-7)M increased [Ca(2+)]i in NG neurons, and the insulin-induced [Ca(2+)]i increase was inhibited by treatment with ghrelin at 10(-8)M. This inhibitory effect of ghrelin was attenuated by [D-Lys(3)]-GHRP-6, an antagonist of growth hormone-secretagogue receptor (GHSR). Des-acyl ghrelin had little effect on insulin-induced [Ca(2+)]i increases in NG neurons. Ghrelin did not affect [Ca(2+)]i increases in response to cholecystokinin (CCK), a hormone that inhibits feeding via vagal afferent neurons, indicating that ghrelin selectively counteracts the insulin action. These results demonstrate that ghrelin via GHSR suppresses insulin-induced activation of NG neurons. The action of ghrelin to counteract insulin effects on NG might serve to efficiently inform the brain of the systemic change between fasting-associated ghrelin-dominant and fed-associated insulin-dominant states for the homeostatic central regulation of feeding and metabolism.

  15. Coordinate increase of telomerase activity and c-Myc expression in Helicobacter pylori-associated gastric diseases

    Institute of Scientific and Technical Information of China (English)

    Guo-Xin Zhang; Yan-Hong Gu; Zhi-Quan Zhao; Shun-Fu Xu; Hong-Ji Zhang; Hong-Di Wang; Bo Hao

    2004-01-01

    AIM: To detect the telomerase activity and c-Myc expression in gastric diseases and to examine the relation between these values and Helicobacter pylori (H pylori) as a risk factor for gastric cancer.METHODS: One hundred and seventy-one gastric samples were studied to detect telomerase activity using a telomerase polymerase chain reaction enzyme linked immunosorbent assay (PCR-ELTSA), and c-Myc expression using immunohistochemistry.RESULTS: The telomerase activity and c-Myc expression were higher in cancers (87.69% and 61.54%) than in noncancerous tissues. They were higher in chronic atrophic gastritis with severe intestinal metaplasia (52.38% and 47.62%) than in chronic atrophic gastritis with mild intestinal metaplasia (13.33% and 16.67%). Tn chronic atrophic gastritis with severe intestinal metaplasia, the telomerase activity and c-Myc expression were higher in cases with -H pylori infection (67.86% and 67.86%) than in those without infection (21.43%and 7.14%). c-Myc expression was higher in gastric cancer with H pylori infection (77.27%) than in that without infection (28.57%). The telomerase activity and c-Nyc expression were coordinately up-regulated in H pylori infected gastric cancer and chronic atrophic gastritis with severe intestinal metaplasia.CONCLUSION: H pylori infection may influence both telomerase activity and c-Myc expression in gastric diseases,especially in chronic atrophic gastritis.

  16. Effect of ghrelin on glucose regulation in mice.

    Science.gov (United States)

    Chacko, Shaji K; Haymond, Morey W; Sun, Yuxiang; Marini, Juan C; Sauer, Pieter J J; Ma, Xiaojun; Sunehag, Agneta L

    2012-05-15

    Improvement of glucose metabolism after bariatric surgery appears to be from the composite effect of the alterations in multiple circulating gut hormone concentrations. However, their individual effect on glucose metabolism during different conditions is not clear. The objective of this study was to determine whether ghrelin has an impact on glycogenolysis, gluconeogenesis, and insulin sensitivity (using a mice model). Rate of appearance of glucose, glycogenolysis, and gluconeogenesis were measured in wild-type (WT), ghrelin knockout (ghrelin(-/-)), and growth hormone secretagogue receptor knockout (Ghsr(-/-)) mice in the postabsorptive state. The physiological nature of the fasting condition was ascertained by a short-term fast commenced immediately at the end of the dark cycle. Concentrations of glucose and insulin were measured, and insulin resistance and hepatic insulin sensitivity were calculated. Glucose concentrations were not different among the groups during the food-deprived period. However, plasma insulin concentrations were lower in the ghrelin(-/-) and Ghsr(-/-) than WT mice. The rates of gluconeogenesis, glycogenolysis, and indexes of insulin sensitivity were higher in the ghrelin(-/-) and Ghsr(-/-) than WT mice during the postabsorptive state. Insulin receptor substrate 1 and glucose transporter 2 gene expressions in hepatic tissues of the ghrelin(-/-) and Ghsr(-/-) were higher compared with that in WT mice. This study demonstrates that gluconeogenesis and glycogenolysis are increased and insulin sensitivity is improved by the ablation of the ghrelin or growth hormone secretagogue receptor in mice.

  17. Ghrelin and melatonin as biomarkers in patients with giardiasis

    Directory of Open Access Journals (Sweden)

    Saleem Khteer Al-Hadraawy

    2016-05-01

    Full Text Available Giardia is the most frequently reported intestinal parasite worldwide. The aim of this study was to investigate the ghrelin, melatonin, glucose and cholesterol concentration in male patients infected with Giardia lamblia. We enrolled 66 patients with Giardiasis and the control groups consisted of healthy subjects (n = 30. The results demonstrated that there was a significant decrease (P < 0.05 in ghrelin levels, while the melatonin, glucose and cholesterol levels were significantly increased (P < 0.05 in giardiasis patients as compared to the healthy group. The obtained results suggest that ghrelin and melatonin could serve as biomarkers in patients infected with G. lamblia.

  18. Expression of ghrelin and the ghrelin receptor in different stages of porcine corpus luteum development and the inhibitory effects of ghrelin on progesterone secretion, 3β-hydroxysteroid dehydrogenase (3β-honestly significant difference (HSD)) activity and protein expression.

    Science.gov (United States)

    Rak-Mardyła, A; Gregoraszczuk, E L; Karpeta, A; Duda, M

    2012-05-01

    Recent studies have suggested that ghrelin plays a direct role in controlling female reproduction. The aim of the present study was to investigate the mRNA and protein expression of ghrelin and its receptor (via real time PCR, Western blot and immunohistochemistry analysis, respectively) in porcine corpora lutea (CL) collected during early (CL1: 1-2 days after ovulation), middle (CL2: 7-10 after ovulation), and late luteal phase (CL3: 13-15 after ovulation). Ghrelin expression and concentration of both acylated and unacylated forms of ghrelin significantly increased during CL development. Immunohistochemistry analysis shown localization of ghrelin protein in the cytoplasm of large luteal cells. No changes in the expression of the ghrelin receptor were observed. Direct in vitro effects of ghrelin on progesterone (P4) secretion and 3-beta-hydroxysteroid dehydrogenase (3β-honestly significant difference (HSD)) activity, which were measured by the conversion of pregnenolone (P5) to P4, and 3β-HSD protein expression were then analyzed. To assess 3β-HSD activities, mature luteal cells were first cultured for 24 h with ghrelin at 100, 250, 500 and 1000 pg/mL with P5, or with aminoglutethimide (AMG). AMG is an inhibitor of CYP11A1-mediated hydroxylation; an addition of AMG and P5 enabled P4 production to serve as an index of 3β-HSD activity. Inhibitory effects of ghrelin on P4 secretion, 3β-HSD activity and protein expression were observed. In conclusion, the presence of ghrelin and its receptor in porcine corpora lutea and the direct inhibitory effects of ghrelin on luteal P4 secretion and 3β-HSD suggest potential auto/paracrine regulation by ghrelin in the luteal phase of ovary function.

  19. Helicobacter pylori and pancreatic diseases

    Institute of Scientific and Technical Information of China (English)

    Milutin; Bulajic; Nikola; Panic; Johannes; Matthias; L?hr

    2014-01-01

    A possible role for Helicobacter pylori(H. pylori) infec-tion in pancreatic diseases remains controversial. H. pylori infection with antral predomination leading to an increase in pancreatic bicarbonate output and induc-ing ductal epithelial cell proliferation could contribute to the development of pancreatic cancer via complex interactions with the ABO genotype, dietary and smok-ing habits and N-nitrosamine exposure of the host. Although the individual study data available so far is inconsistent, several meta-analyses have reported an increased risk for pancreatic cancer among H. pylori seropositive individuals. It has been suggested that H. pylori causes autoimmune pancreatitis due to molecu-lar mimicry between H. pylori a-carbonic anhydrase(a-CA) and human CA type Ⅱ, and between H. pylori plasminogen-binding protein and human ubiquitin-protein ligase E3 component n-recognin 2, enzymes that are highly expressed in the pancreatic ductal andacinar cells, respectively. Future studies involving large numbers of cases are needed in order to examine the role of H. pylori in autoimmune pancreatitis more fully. Considering the worldwide pancreatic cancer burden, as well as the association between autoimmune pan-creatitis and other autoimmune conditions, a complete elucidation of the role played by H. pylori in the gen-esis of such conditions could have a substantial impact on healthcare.

  20. Central but not systemic administration of ghrelin induces wakefulness in mice.

    Directory of Open Access Journals (Sweden)

    Éva Szentirmai

    Full Text Available Ghrelin is a brain-gut peptide hormone widely known for its orexigenic and growth hormone-releasing activities. Findings from our and other laboratories indicate a role of ghrelin in sleep regulation. The effects of exogenous ghrelin on sleep-wake activity in mice are, however, unknown. The aim of the present study was to determine the sleep-modulating effects of ghrelin after central and systemic administrations in mice. Sleep-wake activity after intracerebroventricular (i.c.v. administration of 0.2, 1 and 5 µg ghrelin and intraperitoneal injections of 40, 100, and 400 µg/kg ghrelin prior to light onset were determined in C57BL/6 mice. In addition, body temperature, motor activity and 1-hour food intake was measured after the systemic injections. Sleep effects of systemic ghrelin (40 and 400 µg/kg injected before dark onset were also determined. I.c.v. injection of ghrelin increased wakefulness and suppressed non-rapid-eye-movement sleep and electroencephalographic slow-wave activity in the first hour after injections. Rapid-eye-movement sleep was decreased for 2-4 hours after each dose of ghrelin. Sytemic administration of ghrelin did not induce changes in sleep-wake activity in mice at dark or light onset. Motor activity and body temperature remained unaltered and food intake was significantly increased after systemic injections of ghrelin given prior the light period. These findings indicate that the activation of central, but not peripheral, ghrelin-sensitive mechanisms elicits arousal in mice. The results are consistent with the hypothesis that the activation of the hypothalamic neuronal circuit formed by ghrelin, orexin, and neuropeptide Y neurons triggers behavioral sequence characterized by increased wakefulness, motor activity and feeding in nocturnal rodents.

  1. Acyl Ghrelin Induces Insulin Resistance Independently of GH, Cortisol, and Free Fatty Acids

    Science.gov (United States)

    Vestergaard, Esben T.; Jessen, Niels; Møller, Niels; Jørgensen, Jens Otto Lunde

    2017-01-01

    Ghrelin produced in the gut stimulates GH and ACTH secretion from the pituitary and also stimulates appetite and gastric emptying. We have shown that ghrelin also induces insulin resistance via GH-independent mechanisms, but it is unknown if this effect depends on ambient fatty acid (FFA) levels. We investigated the impact of ghrelin and pharmacological antilipolysis (acipimox) on insulin sensitivity and substrate metabolism in 8 adult hypopituitary patients on stable replacement with GH and hydrocortisone using a 2 × 2 factorial design: Ghrelin infusion, saline infusion, ghrelin plus short-term acipimox, and acipimox alone. Peripheral and hepatic insulin sensitivity was determined with a hyperinsulinemic euglycemic clamp in combination with a glucose tracer infusion. Insulin signaling was assayed in muscle biopsies. Peripheral insulin sensitivity was reduced by ghrelin independently of ambient FFA concentrations and was increased by acipimox independently of ghrelin. Hepatic insulin sensitivity was increased by acipimox. Insulin signaling pathways in skeletal muscle were not consistently regulated by ghrelin. Our data demonstrate that ghrelin induces peripheral insulin resistance independently of GH, cortisol, and FFA. The molecular mechanisms remain elusive, but we speculate that ghrelin is a hitherto unrecognized direct regulator of substrate metabolism. We also suggest that acipimox per se improves hepatic insulin sensitivity. PMID:28198428

  2. Peripheral ghrelin enhances sweet taste food consumption and preference, regardless of its caloric content.

    Science.gov (United States)

    Disse, Emmanuel; Bussier, Anne-Lise; Veyrat-Durebex, Christelle; Deblon, Nicolas; Pfluger, Paul T; Tschöp, Matthias H; Laville, Martine; Rohner-Jeanrenaud, Françoise

    2010-09-01

    Ghrelin is one of the most potent orexigens known to date. While the prevailing view is that ghrelin participates in the homeostatic control of feeding, the question arose as to whether consummatory responses evoked by this compound could be related to search for reward. We therefore attempted to delineate the involvement of ghrelin in the modulation of non-caloric but highly rewarding consumption. We tested the effect of intraperitoneally injected ghrelin on the acceptance and preference for a 0.3% saccharin solution using single bottle tests and free-choice preference test procedures in C57BL6/J mice, as well as in mice lacking the ghrelin receptor (GHSR1a -/-) and their wild-type (WT) littermates. In the single bottle tests, peripheral ghrelin consistently increased the consumption of saccharin, independently of availability of caloric food. In the free-choice preference test procedures, ghrelin increased the preference for saccharin in WT mice, while it did had not effect in GHSR1a -/-animals, indicating that the ghrelin receptor pathway is necessary to mediate this parameter. Peripheral ghrelin enhances intake and preference for a sweet food, regardless of whether the food has caloric content. This effect, mediated through the ghrelin receptor pathway, may serve as additional enhancers of energy intake. Copyright 2010 Elsevier Inc. All rights reserved.

  3. Effects of glucose and amino acids on ghrelin secretion in sheep.

    Science.gov (United States)

    Sugino, Toshihisa; Kawakita, Yuko; Fukumori, Rika; Hasegawa, Yoshihisa; Kojima, Masayasu; Kangawa, Kenji; Obitsu, Taketo; Taniguchi, Kohzo

    2010-04-01

    Two experiments were conducted to elucidate the effects of post-ruminal administration of starch and casein (Exp. 1), plasma amino acids concentrations (Exp. 2), and plasma glucose and insulin concentrations (Exp. 2) on plasma ghrelin concentrations in sheep. In Exp. 1, plasma ghrelin concentrations were determined by four infusion treatments (water, cornstarch, casein and cornstarch plus casein) in four wethers. Abomasal infusion of casein increased plasma alpha-amino N (AAN) concentrations. Infusion of starch or casein alone did not affect plasma ghrelin concentrations, but starch plus casein infusion increased plasma levels of ghrelin, glucose and AAN. In Exp 2, we investigated the effects of saline or amino acids on ghrelin secretion in four wethers. Two hours after the initiation of saline or amino acid infusion into the jugular vein, glucose was also continuously infused to investigate the effects of blood glucose and insulin by hyper-glycemic clump on plasma ghrelin concentrations. Infusion of amino acids alone raised plasma levels of ghrelin, but the higher plasma glucose and insulin concentrations had no effect on plasma ghrelin concentrations. These results suggest that high plasma levels of amino acids can stimulate ghrelin secretion, but glucose and insulin do not affect ghrelin secretion in sheep.

  4. Structure and Physiological Actions of Ghrelin

    OpenAIRE

    Christine Delporte

    2013-01-01

    Ghrelin is a gastric peptide hormone, discovered as being the endogenous ligand of growth hormone secretagogue receptor. Ghrelin is a 28 amino acid peptide presenting a unique n-octanoylation modification on its serine in position 3, catalyzed by ghrelin O-acyl transferase. Ghrelin is mainly produced by a subset of stomach cells and also by the hypothalamus, the pituitary, and other tissues. Transcriptional, translational, and posttranslational processes generate ghrelin and ghrelin-related p...

  5. Does Helicobacter pylori affect portal hypertensive gastropathy?

    Directory of Open Access Journals (Sweden)

    Al Mofleh Ibrahim

    2007-01-01

    Full Text Available Helicobacter pylori (H. pylori is a major etiological factor of peptic ulcer disease (PUD. It is supposed to be a risk factor for the more frequently encountered PUD in patients with liver cirrhosis. Several investigators have evaluated the effect of H. pylori on liver cirrhosis, portal hypertensive gastropathy (PHG and encephalopathy with controversial results. Some reports have shown a higher seroprevalence and suggested a synergistic effect of H. pylori on liver cirrhosis and PHG. However, this increased prevalence is associated with a negative histology and is not influenced by the cause of cirrhosis, PHG, Child class or gender. Most studies have not found any correlation between H. pylori and PHG. In contrast, other studies have reported a markedly lower prevalence of H. pylori in cirrhotics with duodenal ulcer compared to controls. The aim of this article is to review the relationship between H. pylori infection and portal hypertensive gastropathy and the role of H. pylori eradication in cirrhotic patients.

  6. Ghrelin stimulation of growth hormone-releasing hormone neurons is direct in the arcuate nucleus.

    Directory of Open Access Journals (Sweden)

    Guillaume Osterstock

    Full Text Available BACKGROUND: Ghrelin targets the arcuate nucleus, from where growth hormone releasing hormone (GHRH neurones trigger GH secretion. This hypothalamic nucleus also contains neuropeptide Y (NPY neurons which play a master role in the effect of ghrelin on feeding. Interestingly, connections between NPY and GHRH neurons have been reported, leading to the hypothesis that the GH axis and the feeding circuits might be co-regulated by ghrelin. PRINCIPAL FINDINGS: Here, we show that ghrelin stimulates the firing rate of identified GHRH neurons, in transgenic GHRH-GFP mice. This stimulation is prevented by growth hormone secretagogue receptor-1 antagonism as well as by U-73122, a phospholipase C inhibitor and by calcium channels blockers. The effect of ghrelin does not require synaptic transmission, as it is not antagonized by gamma-aminobutyric acid, glutamate and NPY receptor antagonists. In addition, this hypothalamic effect of ghrelin is independent of somatostatin, the inhibitor of the GH axis, since it is also found in somatostatin knockout mice. Indeed, ghrelin does not modify synaptic currents of GHRH neurons. However, ghrelin exerts a strong and direct depolarizing effect on GHRH neurons, which supports their increased firing rate. CONCLUSION: Thus, GHRH neurons are a specific target for ghrelin within the brain, and not activated secondary to altered activity in feeding circuits. These results support the view that ghrelin related therapeutic approaches could be directed separately towards GH deficiency or feeding disorders.

  7. Ghrelin-Reactive Immunoglobulins in Conditions of Altered Appetite and Energy Balance

    Science.gov (United States)

    Fetissov, Sergueï O.; Lucas, Nicolas; Legrand, Romain

    2017-01-01

    Part of circulating ghrelin is bound to immunoglobulins (Ig) protecting it from degradation and preserving its functional activity. This review summarizes the data on ghrelin- and desacyl-ghrelin-reactive IgG in conditions of altered appetite and energy balance. Plasma levels and affinity kinetics of such IgG were compared in patients with obesity and anorexia nervosa (AN) and in animal models of obesity including ob/ob mice, high-fat diet-induced obese mice, and obese Zucker rats as well as in mice after chronic food restriction and activity-based anorexia and in rats with methotrexate-induced anorexia. We show that plasmatic IgG in both obese humans and animals are characterized by increased affinity for ghrelin. In contrast, patients with AN and anorectic rodents all show lower affinity of ghrelin- and desacyl-ghrelin-reactive IgG, respectively, the changes which were not observed in non-anorectic, chronically starved mice. We also show that affinity of ghrelin-reactive IgG correlate with plasma levels of ghrelin. These data point to common mechanisms underlying modifications of affinity kinetics properties of ghrelin-reactive IgG during chronic alterations of energy balance in humans and rodents and support a functional role of such autoantibodies in ghrelin-mediated regulation of appetite. PMID:28191004

  8. Increased seropositivity of Helicobacter pylori cytotoxin-associated gene-A in Behçet's disease.

    Science.gov (United States)

    Apan, Teoman Zafer; Gürsel, Ragip; Dolgun, Alp

    2007-06-01

    Behçet's disease is a systemic vasculitic syndrome with unknown etiology. The aim of the present study was to compare the Helicobacter pylori seropositivity and cytotoxin associated gene-A status in patients with Behçet's disease. Ninety-one patients with Behçet's disease and 83 age- and sex-matched persons with or without any gastrointestinal complaints were included in the study. Demographic characteristics and H. pylori IgG, IgM, and cytotoxin-associated gene-A IgG status of the Behçet's disease and the control groups were analyzed. The influence of eradication therapy on clinical findings was also determined. The prevalence of H. pylori IgG seropositivity was slightly but not significantly higher in patients with Behçet's disease compared to the controls [72 (79.1%) vs 56 (67.5%), (p = 0.082)]. The prevalence of cytotoxin-associated gene A positivity was significantly higher in Behçet's disease compared to the controls [59 (64.8.%) vs 32 (38.5%), respectively, (p = 0.002)]. Eradication of H. pylori has significantly decreased clinical manifestations such as oral and genital ulceration, arthritis/arthralgia, and cutaneous findings of Bahçet's disease. Our study indicates that H. pylori may be involved in the pathogenesis of Behçet's disease or disease activity might be enhanced due to induced inflammation or altered immunity.

  9. Helicobacter  pylori Eradication Therapies in the Era of Increasing Antibiotic Resistance: A Paradigm Shift to Improved Efficacy

    Directory of Open Access Journals (Sweden)

    Sotirios D. Georgopoulos

    2012-01-01

    Full Text Available With the rising prevalence of antimicrobial resistance, the eradication rates of Helicobacter pylori (H. pylori with standard treatments are decreasing to unacceptable levels (i.e., ≤80% in most countries. After these disappointing results, several authorities have proposed that infection with H. pylori should be approached and treated as any other bacterial infectious disease. This implicates that clinicians should prescribe empirical treatments yielding a per protocol eradication of at least 90%. In recent years several treatments producing ≥90% cure rates have been proposed including sequential therapy, concomitant quadruple therapy, hybrid (dual-concomitant therapy, and bismuth-containing quadruple therapy. These treatments are likely to represent the recommended first-line treatments in the near future. In the present paper, we are considering a series of critical issues regarding currently available means and approaches for the management of H. pylori infection. Clinical needs and realistic endpoints are taken into account. Furthermore, emerging strategies for the eradication of H. pylori and the existing evidence of their clinical validation and widespread applicability are discussed.

  10. In1-ghrelin, a splice variant of ghrelin gene, is associated with the evolution and aggressiveness of human neuroendocrine tumors: Evidence from clinical, cellular and molecular parameters.

    Science.gov (United States)

    Luque, Raul M; Sampedro-Nuñez, Miguel; Gahete, Manuel D; Ramos-Levi, Ana; Ibáñez-Costa, Alejandro; Rivero-Cortés, Esther; Serrano-Somavilla, Ana; Adrados, Magdalena; Culler, Michael D; Castaño, Justo P; Marazuela, Mónica

    2015-08-14

    Ghrelin system comprises a complex family of peptides, receptors (GHSRs), and modifying enzymes [e.g. ghrelin-O-acyl-transferase (GOAT)] that control multiple pathophysiological processes. Aberrant alternative splicing is an emerging cancer hallmark that generates altered proteins with tumorigenic capacity. Indeed, In1-ghrelin and truncated-GHSR1b splicing variants can promote development/progression of certain endocrine-related cancers. Here, we determined the expression levels of key ghrelin system components in neuroendocrine tumor (NETs) and explored their potential functional role. Twenty-six patients with NETs were prospectively/retrospectively studied [72 samples from primary and metastatic tissues (30 normal/42 tumors)] and clinical data were obtained. The role of In1-ghrelin in aggressiveness was studied in vitro using NET cell lines (BON-1/QGP-1). In1-ghrelin, GOAT and GHSR1a/1b expression levels were elevated in tumoral compared to normal/adjacent tissues. Moreover, In1-ghrelin, GOAT, and GHSR1b expression levels were positively correlated within tumoral, but not within normal/adjacent samples, and were higher in patients with progressive vs. with stable/cured disease. Finally, In1-ghrelin increased aggressiveness (e.g. proliferation/migration) of NET cells. Altogether, our data strongly suggests a potential implication of ghrelin system in the pathogenesis and/or clinical outcome of NETs, and warrant further studies on their possible value for the future development of molecular biomarkers with diagnostic/prognostic/therapeutic value.

  11. In1-ghrelin, a splice variant of ghrelin gene, is associated with the evolution and aggressiveness of human neuroendocrine tumors: Evidence from clinical, cellular and molecular parameters

    Science.gov (United States)

    Gahete, Manuel D.; Ramos-Levi, Ana; Ibáñez-Costa, Alejandro; Rivero-Cortés, Esther; Serrano-Somavilla, Ana; Adrados, Magdalena; Culler, Michael D.; Castaño, Justo P.; Marazuela, Mónica

    2015-01-01

    Ghrelin system comprises a complex family of peptides, receptors (GHSRs), and modifying enzymes [e.g. ghrelin-O-acyl-transferase (GOAT)] that control multiple pathophysiological processes. Aberrant alternative splicing is an emerging cancer hallmark that generates altered proteins with tumorigenic capacity. Indeed, In1-ghrelin and truncated-GHSR1b splicing variants can promote development/progression of certain endocrine-related cancers. Here, we determined the expression levels of key ghrelin system components in neuroendocrine tumor (NETs) and explored their potential functional role. Twenty-six patients with NETs were prospectively/retrospectively studied [72 samples from primary and metastatic tissues (30 normal/42 tumors)] and clinical data were obtained. The role of In1-ghrelin in aggressiveness was studied in vitro using NET cell lines (BON-1/QGP-1). In1-ghrelin, GOAT and GHSR1a/1b expression levels were elevated in tumoral compared to normal/adjacent tissues. Moreover, In1-ghrelin, GOAT, and GHSR1b expression levels were positively correlated within tumoral, but not within normal/adjacent samples, and were higher in patients with progressive vs. with stable/cured disease. Finally, In1-ghrelin increased aggressiveness (e.g. proliferation/migration) of NET cells. Altogether, our data strongly suggests a potential implication of ghrelin system in the pathogenesis and/or clinical outcome of NETs, and warrant further studies on their possible value for the future development of molecular biomarkers with diagnostic/prognostic/therapeutic value. PMID:26124083

  12. Polymorphisms and haplotypes of the interleukin 2 gene are associated with an increased risk of gastric cancer. The possible involvement of Helicobacter pylori.

    Science.gov (United States)

    Melchiades, Jessica L; Zabaglia, Luanna M; Sallas, Mayara L; Orcini, Wilson A; Chen, Elizabeth; Smith, Marilia A C; Payão, Spencer L M; Rasmussen, Lucas T

    2017-08-01

    Interleukin 2 (IL-2) is a pro-inflammatory cytokine that is mainly synthesized by immunoregulatory T helper cells and which plays an important role in antitumor immunity. Helicobacter pylori (H. pylori) is a gram-negative bacterium that colonizes the gastric mucosa and induces the production of IL-2. This process increases the magnitude of inflammation and may influence the development of gastric pathologies. In light of the possible involvement of IL-2 and the presence of H. pylori in gastric diseases, this study investigated possible associations between the IL-2 polymorphisms +114 T>G (rs2069763) and -330 T>G (rs2069762) and the development of gastric cancer; these associations were then correlated with the presence of H. pylori. Gastric biopsies were obtained from 294 dyspeptic patients (173♀/123♂). Of these samples, 181 were chronic gastritis samples (102♀/79), 62 were samples of intact gastric mucosa (47♀/15♂), and 51 were samples of gastric cancer (22♀/29♂). PCR-RFLP was used to characterize the +114 T>G and -330 T>G polymorphisms. Considering the genetic characteristics of the study population and based on the codominant model, a high risk of gastric cancer among patients with normal gastric tissue and patients with gastric cancer was found in subjects with the IL-2-330 GG genotype (OR=6.43, 95% CI: 1.47-28.10, p=0.044). The data was adjusted for the presence of H. pylori. Among patients with gastritis and patients with gastric cancer, a high risk was found among subjects with the IL-2-330 GG genotype (OR=4.47, 95% CI: 1.84-10.84, p=0.0022). When the IL-2 +114 polymorphism was analyzed, similar results were found. Among the patients with normal gastric tissue and the patients with gastric cancer, subjects carrying the +114 TT genotype were found to be at a high risk of gastric cancer (OR=5.97, 95% CI: 1.60-22.27, p=0.013). This data was also adjusted for the presence of H. pylori. Among patients with gastritis and patients with gastric cancer

  13. Helicobacter pylori

    OpenAIRE

    BATESON, M

    2000-01-01

    Helicobacter pylori infection is a major cause of peptic ulcer disease, and its detection and eradication are now an important part of gastroenterology. Effective regimes are available which will eliminate the organism in about 90% of cases in developed countries.


Keywords: Helicobacter pylori

  14. Ghrelin inhibits LPS-induced release of IL-6 from mouse dopaminergic neurones

    OpenAIRE

    Beynon, Amy L; Brown, M. Rowan; Wright, Rhiannon; Rees, Mark I.; Sheldon, I Martin; Davies, Jeffrey S.

    2013-01-01

    Background Ghrelin is an orexigenic stomach hormone that acts centrally to increase mid-brain dopamine neurone activity, amplify dopamine signaling and protect against neurotoxin-induced dopamine cell death in the mouse substantia nigra pars compacta (SNpc). In addition, ghrelin inhibits the lipopolysaccharide (LPS)-induced release of pro-inflammatory cytokines from peripheral macrophages, T-cells and from LPS stimulated microglia. Here we sought to determine whether ghrelin attenuates pro-in...

  15. Oral 'hydrogen water' induces neuroprotective ghrelin secretion in mice.

    Science.gov (United States)

    Matsumoto, Akio; Yamafuji, Megumi; Tachibana, Tomoko; Nakabeppu, Yusaku; Noda, Mami; Nakaya, Haruaki

    2013-11-20

    The therapeutic potential of molecular hydrogen (H₂) is emerging in a number of human diseases and in their animal models, including in particular Parkinson's disease (PD). H₂ supplementation of drinking water has been shown to exert disease-modifying effects in PD patients and neuroprotective effects in experimental PD model mice. However, H₂ supplementation does not result in detectable changes in striatal H₂ levels, indicating an indirect effect. Here we show that H₂ supplementation increases gastric expression of mRNA encoding ghrelin, a growth hormone secretagogue, and ghrelin secretion, which are antagonized by the β1-adrenoceptor blocker, atenolol. Strikingly, the neuroprotective effect of H₂ water was abolished by either administration of the ghrelin receptor-antagonist, D-Lys(3) GHRP-6, or atenolol. Thus, the neuroprotective effect of H₂ in PD is mediated by enhanced production of ghrelin. Our findings point to potential, novel strategies for ameliorating pathophysiology in which a protective effect of H₂ supplementation has been demonstrated.

  16. Ghrelin inhibits insulin secretion through the AMPK-UCP2 pathway in beta cells.

    Science.gov (United States)

    Wang, Ying; Nishi, Masahiro; Doi, Asako; Shono, Takeshi; Furukawa, Yasushi; Shimada, Takeshi; Furuta, Hiroto; Sasaki, Hideyuki; Nanjo, Kishio

    2010-04-16

    Ghrelin inhibits insulin secretion partly via induction of IA-2beta. However, the orexigenic effect of ghrelin is mediated by the AMP-activated protein kinase (AMPK)-uncoupling protein 2 (UCP2) pathway. Here, we demonstrate that ghrelin's inhibitory effect on insulin secretion also occurs through the AMPK-UCP2 pathway. Ghrelin increased AMPK phosphorylation and UCP2 mRNA expression in MIN6 insulinoma cells. Overexpression or downregulation of UCP2 attenuated or enhanced insulin secretion, respectively. Furthermore, AMPK activator had a similar effect to ghrelin on UCP2 and insulin secretion in MIN6 cells. In conclusion, ghrelin's inhibitory effect on insulin secretion is partly mediated by the AMPK-UCP2 pathway, which is independent of the IA-2beta pathway.

  17. Effects of exercise on the levels of peptide YY and ghrelin.

    Science.gov (United States)

    Li, J-B; Asakawa, A; Li, Y; Cheng, K; Inui, A

    2011-03-01

    Ghrelin and peptide YY (PYY) are brain-gut peptides that have a variety of physiological functions and are involved in energy regulation. Thus far, abnormalities in the expression and secretion of ghrelin and PYY are known to occur in lifestyle-related diseases, including obesity, and the improvement of these abnormalities has become an important challenge. Exercise has recently been reported to influence ghrelin and PYY concentrations. Exercise increases the PYY secretion. The effects of exercise on ghrelin levels vary with the study subject, timing of exercise, and duration of exercise. Here, we review the findings of recent studies on the association of PYY and ghrelin with obesity, particularly, on the influence of exercise on PYY and ghrelin levels. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York.

  18. Rikkunshito and ghrelin secretion.

    Science.gov (United States)

    Takeda, Hiroshi; Muto, Shuichi; Nakagawa, Koji; Ohnishi, Shunsuke; Asaka, Masahiro

    2012-01-01

    Rikkunshito is a kampo herbal medicine which is widely used in Japan for the treatment of the upper gastrointestinal symptoms of patients with functional dyspepsia (FD), gastroesophageal reflux disease (GERD), dyspeptic symptoms of postgastrointestinal surgery patients, and chemotherapy-induced dyspepsia in cancer patients. Recently, very unique characteristics of rikkunshito have been unveiled; oral administration of rikkunshito potentiates orexigenic action of ghrelin through several different mechanisms. In addition, several lines of evidence obtained from both animal and human studies indicate that rikkunshito can be an attractive and promising therapeutic option for the anorectic conditions including cisplatin-induced dyspepsia, anorexia of aging, stress-induced hypophagia, cancer cachexia-anorexia syndrome. In this review, we will highlight what is known about the orexigenic effect of rikkunshito with a special focus on an interaction with ghrelin signaling system.

  19. Helicobacter pylori with stronger intensity of CagA phosphorylation lead to an increased risk of gastric intestinal metaplasia and cancer

    Directory of Open Access Journals (Sweden)

    Cheng Hsiu-Chi

    2011-05-01

    Full Text Available Abstract Background Nearly all Taiwanese H. pylori stains are cagA-genopositive and encode CagA protein. In this study, we evaluated whether different intensity of tyrosine phosphorylated-CagA (p-CagA had an impact on the clinical diseases and histological outcomes in this area. Results We enrolled 469 dyspeptic patients and prospectively obtained the gastric biopsy specimens and the H. pylori isolates. These patients were categorized according to the clinical diseases, such as duodenal ulcer, gastric ulcer, gastric cancer, and gastritis with or without intestinal metaplasia. Their gastric specimens were reviewed by the updated Sydney's system. Furthermore, a total of 146 patients were randomly selected from each clinical category for evaluation of their isolates' p-CagA intensity by in vitro AGS cells co-culture. The p-CagA was sparse in 30 (20.5%, weak in 59 (40.5%, and strong in 57 (39% isolates. The isolates from the patients of gastric cancer or gastritis with intestinal metaplasia had stronger p-CagA intensity than those of gastritis without intestinal metaplasia (p ≤ 0.002. Moreover, the patients infected with isolates with strong or weak p-CagA intensity had a higher risk of gastric intestinal metaplasia (p Conclusions Infection with H. pylori stains with stronger p-CagA intensity may lead to an increased risk of gastric intestinal metaplasia and cancer.

  20. Helicobacter pylori Infection Increase the Risk of Myocardial Infarction: A Meta-Analysis of 26 Studies Involving more than 20,000 Participants.

    Science.gov (United States)

    Liu, Juan; Wang, Feng; Shi, Songli

    2015-06-01

    Myocardial infarction is a fatal cardiovascular disease and one of the most common death causes all around the world. The aim of the meta-analysis was to quantify the risk of myocardial infarction associated with Helicobacter pylori infection. A literature search was performed to identify studies published before 14 July, 2014, for relevant risk estimates. Fixed and random effect meta-analytical techniques were conducted for myocardial infarction. Twenty-six case-control studies involving 5829 myocardial infarction patients and more than 16,000 controls were included. Helicobacter pylori infection was associated with an increased risk of myocardial infarction (OR: 2.10, 95%CI: 1.75-2.53, p = .06). We also discovered a significant association between the bacteria and risk of myocardial infarction in young people (OR: 1.93, 95% CI: 1.41-2.66, p = .07), in elder people (OR: 2.02, 95% CI: 1.60-2.54, p = .29), in Caucasians (OR: 2.29, 95% CI: 1.99-2.63, p = .12), and in Asians (OR: 1.75, 95% CI: 1.12-2.73, p = .08). Our meta-analyses suggested a possible indication of relationship between Helicobacter pylori infection and the risk of myocardial infarction. The pathogenicity might not be affected by age and race. More researches should be conducted to explore the mechanisms involved. © 2014 John Wiley & Sons Ltd.

  1. The Effects of Ghrelin on Energy Balance and Psychomotor Activity in a Goldfish Model: An Overview

    Directory of Open Access Journals (Sweden)

    Ki Sung Kang

    2011-01-01

    Full Text Available The goldfish (Carassius auratus has a number of merits as a laboratory animal, and we have extensively identified the mechanisms by which ghrelin regulates food intake in this species. For the first time, we have purified and characterized 11 molecular variants of ghrelin that are present in goldfish intestine and shown that 17-residue ghrelin, the predominant form with n-octanoyl modification, is biologically active and implicated in the regulation of food intake as an endogenous orexigenic factor. Ghrelin and its receptor system are present not only in peripheral tissues such as stomach and intestine, but also in the central nervous system. Recent studies have also revealed that a number of neuropeptides are widely distributed in the brain in key areas of emotional regulation, and their role as modulators of behavioral states is being increasingly recognized. Interestingly, administration of ghrelin induces an orexigenic effect and also modifies locomotor activity, suggesting the involvement of ghrelin in feeding control and regulation of energy balance. Information derived from studies of ghrelin has been increasing, and important results have been obtained from both fish and mammals. Here, we present an overview of the effects of ghrelin on energy balance and psychomotor activity in the goldfish as an animal model. The available data provide an insight into evolutionary background of ghrelin's multiple actions on energy homeostasis in vertebrates.

  2. Random Lead Time of the acute ghrelin response to a psychological stress

    Directory of Open Access Journals (Sweden)

    Geetha.T

    2014-12-01

    Full Text Available Ghrelin is a growth hormone and cortisol secretagogue that plays an important role in appetite and weight regulation. It is not known whether ghrelin is involved in the eating response to stress in humans. In the present study we examined the effects of psychologically induced stress on plasma ghrelin levels in patients with bingeeating disorder (BED and in healthy subjects of normal or increased body mass index (BMI. Volunteers were subjected to the standardized trier social stress test (TSST. Basal ghrelin levels in patients were at an intermediate level between thin and healthy obese subjects, but this difference did not attain statistical significance. There were no differences in ghrelin levels throughout the test among the groups after correction for BMI, age and gender. A significant difference in the trend time of ghrelin was revealed when the three groups were analyzed according to their cortisol response to stress. Ghrelin levels increased in cortisol responders whereas no change or a decrease in ghrelin levels occurred in cortisol non-responders. We also found Optimal time T*, Minimal Repair δ and Random Lead Time g to minimize the ghrelin level.

  3. Glucagon stimulates ghrelin secretion through the activation of MAPK and EPAC and potentiates the effect of norepinephrine.

    Science.gov (United States)

    Gagnon, Jeffrey; Anini, Younes

    2013-02-01

    Ghrelin is a stomach-derived orexigenic hormone whose levels in circulation are altered by energy availability. Like ghrelin, the glucotropic hormone glucagon increases in the fasting state and serves to normalize energy levels. We hypothesized that glucagon can directly stimulate stomach ghrelin production. To verify this hypothesis, we used a primary culture of dispersed rat stomach cells. We first demonstrated that stomach ghrelin cells express the glucagon receptor (GluR). Glucagon (1-100 nM) significantly stimulated ghrelin secretion and proghrelin mRNA expression, and co-incubation with a GluR inhibitor prevented glucagon's action. The MAP kinase inhibitor (PD98058) reduced the glucagon-stimulated ghrelin secretion and proghrelin mRNA expression. Furthermore, glucagon treatment increased the phosphorylation of ERK1/2. Glucagon also increased intracellular cAMP levels, and inhibition of adenylate cyclase reduced glucagon's effect on ghrelin secretion. Surprisingly, inhibiting protein kinase A (PKA) (using H89 and phosphorothioate [Rp]-cAMP) did not prevent glucagon-stimulated ghrelin secretion. Instead, inhibiting the exchange protein activated by cAMP (EPAC) with Brefeldin-A was able to significantly reduce glucagon-stimulated ghrelin secretion. Furthermore, the EPAC agonist (8-pCPT) significantly stimulated ghrelin secretion. Depleting endoplasmic reticulum calcium stores or blocking voltage-dependant calcium channels prevented glucagon stimulated ghrelin secretion. Finally, co-incubation with the sympathetic neurotransmitter norepinephrine potentiated the glucagon stimulation of ghrelin secretion. Our findings are the first to show a direct link between glucagon and stomach ghrelin production and secretion and highlight the role of MAPK, the PKA-independent EPAC pathway, and the synergy between norepinephrine and glucagon in ghrelin release.

  4. Ghrelin levels are not regulated by recombinant leptin administration and/or three days of fasting in healthy subjects.

    Science.gov (United States)

    Chan, Jean L; Bullen, John; Lee, Jennifer H; Yiannakouris, Nikos; Mantzoros, Christos S

    2004-01-01

    Ghrelin, a stomach-derived orexigenic peptide, and leptin, a fat-derived anorexigenic hormone, act primarily in the hypothalamus to regulate energy homeostasis and have been reported to be regulated in opposite directions by acute and chronic changes in nutritional state. Nutritional, anthropometric, and hormonal predictors of circulating ghrelin have not yet been fully elucidated, and whether ghrelin is regulated by leptin in humans remains unknown. To address these questions, we performed cross-sectional and interventional studies. In 120 healthy men and women, ghrelin was negatively associated with leptin as well as overall and central adiposity, but not with total energy or specific macronutrient intake. The sexual dimorphism in ghrelin levels (higher levels in women than in men) and the negative correlation between ghrelin and insulin are largely mediated by central adiposity. In six lean men, complete fasting for 3 d resulted in a low leptin state without a major change in fat mass and abolished the meal-related secretory pattern of ghrelin without increasing 24-h ghrelin levels. In addition, recombinant human leptin administration in physiological and pharmacological doses did not regulate ghrelin over several hours to a few days. These data do not support a role for regulation of circulating ghrelin by leptin levels independently of changes in adiposity and suggest that the leptin and ghrelin systems for energy homeostasis function independently of each other in healthy humans.

  5. The obestatin/ghrelin ratio and ghrelin genetics in adult celiac patients before and after a gluten-free diet, in irritable bowel syndrome patients and healthy individuals.

    Science.gov (United States)

    Russo, Francesco; Chimienti, Guglielmina; Linsalata, Michele; Clemente, Caterina; Orlando, Antonella; Riezzo, Giuseppe

    2017-02-01

    Ghrelin levels and obestatin/ghrelin ratio have been proposed as activity markers in ulcerative colitis, but no data are available in celiac disease (CD) and irritable bowel syndrome (IBS). Our aims were as follows: (a) to assess obestatin and ghrelin concentrations in adult active CD patients, diarrhea-predominant IBS (IBS-d), and healthy controls (HC) in relation to intestinal permeability; (b) to evaluate the ghrelin-obestatin profile in CD patients after a 1-year gluten-free diet (GFD); and (c) to establish the impact of ghrelin genetics. The study included 31 CD patients, 28 IBS-d patients, and 19 HC. Intestinal permeability, assayed by high-performance liquid chromatography determination of urinary lactulose (La)/mannitol (Ma), and circulating concentrations of obestatin, ghrelin, and their ratio were evaluated at enrollment and after GFD. The ghrelin single nucleotide polymorphisms Arg51Gln (rs34911341), Leu72Met (rs696217), and Gln90Leu (rs4684677) were analyzed. Intestinal permeability was impaired in CD patients and ameliorated after GFD. Ghrelin was significantly (P=0.048) higher and the obestatin/ghrelin ratio was significantly (P=0.034) lower in CD patients compared with both IBS-d and HC, and GFD reduced the peptide levels, but without reaching the concentrations in HC. Significant differences (PIntestinal permeability is altered in CD, but not in IBS-d patients, and ghrelin levels increase in CD patients as observed in other inflammatory conditions. Moreover, a role for ghrelin genetics is hypothesized in sustaining the many pathogenetic components of these different pathologies, but with a similar symptom profile.

  6. Sensing of fatty acids for octanoylation of ghrelin involves a gustatory G-protein.

    Directory of Open Access Journals (Sweden)

    Sara Janssen

    Full Text Available BACKGROUND: Ghrelin is an important regulator of energy--and glucose homeostasis. The octanoylation at Ser(3 is essential for ghrelin's biological effects but the mechanisms involved in the octanoylation are unknown. We investigated whether the gustatory G-protein, α-gustducin, and the free fatty acid receptors GPR40 and GPR120 are involved in the fatty acid sensing mechanisms of the ghrelin cell. METHODS: Wild-type (WT and α-gustducin knockout (gust(-/- mice were fed a glyceryl trioctanoate-enriched diet (OD during 2 weeks. Ghrelin levels and gastric emptying were determined. Co-localization between GPR40, GPR120 and ghrelin or α-gustducin/α-transducin was investigated by immunofluorescence staining. The role of GPR120 in the effect of medium and long chain fatty acids on the release of ghrelin was studied in the ghrelinoma cell line, MGN3-1. The effect of the GPR40 agonist, MEDICA16, and the GPR120 agonist, grifolic acid, on ghrelin release was studied both in vitro and in vivo. RESULTS: Feeding an OD specifically increased octanoyl ghrelin levels in the stomach of WT mice but not of gust(-/- mice. Gastric emptying was accelerated in WT but not in gust(-/- mice. GPR40 was colocalized with desoctanoyl but not with octanoyl ghrelin, α-gustducin or α-transducin positive cells in the stomach. GPR120 only colocalized with ghrelin in the duodenum. Addition of octanoic acid or α-linolenic acid to MGN3-1 cells increased and decreased octanoyl ghrelin levels, respectively. Both effects could not be blocked by GPR120 siRNA. MEDICA16 and grifolic acid did not affect ghrelin secretion in vitro but oral administration of grifolic acid increased plasma ghrelin levels. CONCLUSION: This study provides the first evidence that α-gustducin is involved in the octanoylation of ghrelin and shows that the ghrelin cell can sense long- and medium-chain fatty acids directly. GPR120 but not GPR40 may play a role in the lipid sensing cascade of the ghrelin cell.

  7. Chronic Renal Failure, Cachexia, and Ghrelin

    OpenAIRE

    Laviano, A.; Krznaric, Z.; Sanchez-Lara, K.; Preziosa, I.; Cascino, A; Rossi Fanelli, F.

    2010-01-01

    Protein energy wasting is frequently observed in patients with advanced chronic renal failure and end-stage renal disease. Anorexia and reduced food intake are critical contributing factors and negatively impact on patients' survival. Ghrelin is a prophagic peptide produced by the stomach and acting at the hypothalamic level to increase the activity of orexigenic neurons. In patients with chronic renal disease, plasma levels are increased as a likely effect of reduced renal clearance. Neverth...

  8. Interpersonal Stressors Predict Ghrelin and Leptin Levels in Women

    Science.gov (United States)

    Jaremka, Lisa M.; Belury, Martha A.; Andridge, Rebecca R.; Malarkey, William B.; Glaser, Ronald; Christian, Lisa; Emery, Charles F.; Kiecolt-Glaser, Janice K.

    2014-01-01

    Objective Stressful events enhance risk for weight gain and adiposity. Ghrelin and leptin, two hormones that are implicated in appetite regulation, may link stressful events to weight gain; a number of rodent studies suggest that stressors increase ghrelin production. The present study investigated the links among daily stressors, ghrelin and leptin, and dietary intake in humans. Method Women (N = 50) completed three study appointments that were scheduled at least 2 weeks apart. At each visit, women arrived fasting and ate a standardized breakfast and lunch. Blood samples were collected 45 minutes after each meal. Women completed a self-report version of the Daily Inventory of Stressful Events (DISE) at each appointment. Two composites were created from the DISE data, reflecting the number of stressors that did and did not involve interpersonal tension. Results Women who experienced more stressors involving interpersonal tension had higher ghrelin and lower leptin levels than those who experienced fewer interpersonal stressors. Furthermore, women who experienced more interpersonal stressors had a diet that was higher in calories, fat, carbohydrates, protein, sugar, sodium, and fiber, and marginally higher in cholesterol, vegetables (but not fruits), vitamin A, and vitamin C. Stressors that did not involve interpersonal tension were unrelated to ghrelin and leptin levels or any of the dietary components examined. Conclusions These data suggest that ghrelin and leptin may link daily interpersonal stressors to weight gain and obesity. PMID:25032903

  9. Helicobacter pylori Induced Phosphatidylinositol-3-OH Kinase/mTOR Activation Increases Hypoxia Inducible Factor-1α to Promote Loss of Cyclin D1 and G0/G1 Cell Cycle Arrest in Human Gastric Cells

    Science.gov (United States)

    Canales, Jimena; Valenzuela, Manuel; Bravo, Jimena; Cerda-Opazo, Paulina; Jorquera, Carla; Toledo, Héctor; Bravo, Denisse; Quest, Andrew F. G.

    2017-01-01

    Helicobacter pylori (H. pylori) is a human gastric pathogen that has been linked to the development of several gastric pathologies, such as gastritis, peptic ulcer, and gastric cancer. In the gastric epithelium, the bacterium modifies many signaling pathways, resulting in contradictory responses that favor both proliferation and apoptosis. Consistent with such observations, H. pylori activates routes associated with cell cycle progression and cell cycle arrest. H. pylori infection also induces the hypoxia-induced factor HIF-1α, a transcription factor known to promote expression of genes that permit metabolic adaptation to the hypoxic environment in tumors and angiogenesis. Recently, however, also roles for HIF-1α in the repair of damaged DNA and inhibition of gene expression were described. Here, we investigated signaling pathways induced by H. pylori in gastric cells that favor HIF-1α expression and the consequences thereof in infected cells. Our results revealed that H. pylori promoted PI3K/mTOR-dependent HIF-1α induction, HIF-1α translocation to the nucleus, and activity as a transcription factor as evidenced using a reporter assay. Surprisingly, however, transcription of known HIF-1α effector genes evaluated by qPCR analysis, revealed either no change (LDHA and GAPDH), statistically insignificant increases SLC2A1 (GLUT-1) or greatly enhance transcription (VEGFA), but in an HIF-1α-independent manner, as quantified by PCR analysis in cells with shRNA-mediated silencing of HIF-1α. Instead, HIF-1α knockdown facilitated G1/S progression and increased Cyclin D1 protein half-life, via a post-translational pathway. Taken together, these findings link H. pylori-induced PI3K-mTOR activation to HIF-1α induced G0/G1 cell cycle arrest by a Cyclin D1-dependent mechanism. Thus, HIF-1α is identified here as a mediator between survival and cell cycle arrest signaling activated by H. pylori infection. PMID:28401064

  10. Ghrelin directly stimulates adult hippocampal neurogenesis: implications for learning and memory.

    Science.gov (United States)

    Li, Endan; Chung, Hyunju; Kim, Yumi; Kim, Dong Hyun; Ryu, Jong Hoon; Sato, Takahiro; Kojima, Masayasu; Park, Seungjoon

    2013-01-01

    Adult hippocampal neurogenesis is important in mediating hippocampal-dependent learning and memory. Exogenous ghrelin is known to stimulate progenitor cell proliferation in the dentate gyrus of adult hippocampus. The aim of this study was to investigate the role of endogenous ghrelin in regulating the in vivo proliferation and differentiation of the newly generating cells in the adult hippocampus using ghrelin knockout (GKO) mice. Targeted deletion of ghrelin gene resulted in reduced numbers of progenitor cells in the subgranular zone (SGZ) of the hippocampus, while ghrelin treatment restored progenitor cell numbers to those of wild-type controls. We also found that not only the number of bromodeoxyuridine (BrdU)-positive cells but also the fraction of immature neurons and newly generated neurons were decreased in the GKO mice, which were increased by ghrelin replacement. Additionally, in the GKO mice, we observed impairment of memory performance in Y-maze task and novel object recognition test. However, these functional deficiencies were attenuated by ghrelin administration. These results suggest that ghrelin directly induces proliferation and differentiation of adult neural progenitor cells in the SGZ. Our data suggest ghrelin may be a plausible therapeutic potential to enhance learning and memory processes.

  11. Islet β-cell ghrelin signaling for inhibition of insulin secretion.

    Science.gov (United States)

    Dezaki, Katsuya; Yada, Toshihiko

    2012-01-01

    Ghrelin, an acylated 28-amino acid peptide, was isolated from the stomach, where circulating ghrelin is produced predominantly. In addition to its unique role in regulating growth-hormone release, mealtime hunger, lipid metabolism, and the cardiovascular system, ghrelin is involved in the regulation of glucose metabolism. Ghrelin is expressed in pancreatic islets and released into pancreatic microcirculations. Ghrelin inhibits insulin release in mice, rats, and humans. Pharmacological and genetic blockades of islet-derived ghrelin markedly augment glucose-induced insulin release. The signal transduction mechanisms of ghrelin in islet β-cells are very unique, being distinct from those utilized for growth-hormone release. Ghrelin attenuates the glucose-induced cAMP production and PKA activation, which drives activation of Kv channels and suppression of the glucose-induced [Ca(2+)](i) increase and insulin release in β-cells. Insulinostatic function of the ghrelin-GHS-R system in islets is a potential therapeutic target for type 2 diabetes. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Serum levels of tumor necrosis factor-α, interleukin-6 and interleukin-8 are not increased in dyspeptic patients with Helicobacter pylori-associated gastritis

    Directory of Open Access Journals (Sweden)

    Taner Bayraktaroğlu

    2004-01-01

    Full Text Available Introduction: Helicobacter pylori (H. pylori is a non-invasive microorganism causing intense gastric mucosal inflammatory and immune reaction. H. pylori-induced gastric mucosal cytokine overproduction has been clearly documented previously. The stomach has a large surface area and continuous spill-over of locally produced cytokines into the blood stream is a possibility. There are few and conflicting data on circulatory proinflammatory cytokine levels in patients with H. pylori infection.

  13. HELICOBACTER PYLORI

    Science.gov (United States)

    Helicobacter pylori is a pathogenic bacteria which inhabits the human stomach and upper gastrointestinal tract. This encyclopedic entry summarizes the potential role of this organism as a waterborne pathogen. Information is provided on the physiology and morphology of this bacter...

  14. HELICOBACTER PYLORI

    Science.gov (United States)

    Helicobacter pylori is a pathogenic bacteria which inhabits the human stomach and upper gastrointestinal tract. This encyclopedic entry summarizes the potential role of this organism as a waterborne pathogen. Information is provided on the physiology and morphology of this bacter...

  15. Thyroid hormone modulates food intake and glycemia via ghrelin secretion in Zucker fatty rats.

    Science.gov (United States)

    Patel, K; Joharapurkar, A; Dhanesha, N; Patel, V; Kshirsagar, S; Raval, P; Raval, S; Jain, M R

    2014-10-01

    Hyperthyroidism is known to increase food intake and central administration of thyroid hormone shows acute orexigenic effects in rodents. We investigated whether T3 influences appetite and glucose homeostasis by modulating circulating ghrelin, an important orexigenic hormone, in Zucker fatty rats. The acute anorectic effects of T3 and ghrelin mimetic MK-0677 were studied in rats trained for fasting induced food intake. The serum concentration of T3, ghrelin, glucose, triglycerides, and liver glycogen were estimated. The involvement of sympathetic nervous system was evaluated by conducting similar experiments in vagotomized rats. T3 increased food intake and glucose in rats over 4 h, with increase in serum T3 and decrease in liver glycogen. T3 treatment was associated with increase in serum ghrelin. An additive effect on appetite and glucose was observed when T3 (oral) was administered with central (intracerebroventricular) administration of a ghrelin mimetic, MK-0677. Ghrelin antagonist, compound 8a, antagonized the hyperglycemic and hyperphagic effects of T3. In vagotomized rats, T3 did not show increase in appetite as well as glucose. Serum ghrelin levels were unchanged in these animals after T3 treatment. However, T3 showed increase in serum triglyceride levels indicating its peripheral lipolytic effect, in vagotomized as well as sham treated animals. To conclude, acute orexigenic and hyperglycemic effects of T3 are associated with ghrelin secretion and activity. This effect seems to be mediated via vagus nerves, and is independent of glucoregulatory hormones.

  16. Calorie-restricted weight loss reverses high-fat diet-induced ghrelin resistance, which contributes to rebound weight gain in a ghrelin-dependent manner.

    Science.gov (United States)

    Briggs, Dana I; Lockie, Sarah H; Wu, Qunli; Lemus, Moyra B; Stark, Romana; Andrews, Zane B

    2013-02-01

    Twelve weeks of high-fat diet feeding causes ghrelin resistance in arcuate neuropeptide Y (NPY)/agouti-related protein (AgRP) neurons. In the current study, we investigated whether diet-induced weight loss could restore NPY/AgRP neuronal responsiveness to ghrelin and whether ghrelin mediates rebound weight gain after calorie-restricted (CR) weight loss. Diet-induced obese (DIO) mice were allocated to one of two dietary interventions until they reached the weight of age-matched lean controls. DIO mice received chow diet ad libitum or chow diet with 40% CR. Chow-fed and high-fat-fed mice served as controls. Both dietary interventions normalized body weight, glucose tolerance, and plasma insulin. We show that diet-induced weight loss with CR increases total plasma ghrelin, restores ghrelin sensitivity, and increases hypothalamic NPY and AgRP mRNA expression. We propose that long-term DIO creates a higher body weight set-point and that weight loss induced by CR, as seen in the high-fat CR group, provokes the brain to protect the new higher set-point. This adaptation to weight loss likely contributes to rebound weight gain by increasing peripheral ghrelin concentrations and restoring the function of ghrelin-responsive neuronal populations in the hypothalamic arcuate nucleus. Indeed, we also show that DIO ghrelin-knockout mice exhibit reduced body weight regain after CR weight loss compared with ghrelin wild-type mice, suggesting ghrelin mediates rebound weight gain after CR weight loss.

  17. A transient ghrelin surge occurs just before feeding in a scheduled meal-fed sheep.

    Science.gov (United States)

    Sugino, T; Hasegawa, Y; Kikkawa, Y; Yamaura, J; Yamagishi, M; Kurose, Y; Kojima, M; Kangawa, K; Terashima, Y

    2002-07-12

    Ghrelin, a gastric-derived peptide, has recently been identified as an endogenous natural ligand for the growth hormone (GH) secretagogue receptor. However, secretory characteristics of ghrelin are still obscure in ruminants. To investigate the diurnal rhythm in ghrelin secretion and its relationship to GH secretion, plasma ghrelin and GH concentrations were determined in Suffolk rams fed with a roughage diet once daily (Experiment 1). Abrupt increases (Pghrelin occurred just before a meal-feeding compared with that at 1h before feeding, then rapidly fell with a minimum during the feeding. A pulsatile surge (Pghrelin, was observed during the feeding. In Experiment 2, plasma ghrelin and GH were determined in sheep subjected to a pseudo-feeding of 2h to determine whether feed ingestion itself influences ghrelin and GH secretions. Compared with those at 1h before feeding, a tendency of increases (Pghrelin and significant increases (Pghrelin temporally declined within 1h after the start of the pseudo-feeding, and increased again and maintained higher levels during the last period of the pseudo-feeding. These results suggest that the transient surge of ghrelin secretion just before a scheduled meal feeding would not be due to the ingestion of feed, and that a pulsatile increase in plasma GH during the actual- or pseudo-feeding could be induced by the transient ghrelin surge.

  18. Central leptin versus ghrelin: effects on bone marrow adiposity and gene expression.

    Science.gov (United States)

    Ambati, Suresh; Li, Qiang; Rayalam, Srujana; Hartzell, Diane L; Della-Fera, Mary Anne; Hamrick, Mark W; Baile, Clifton A

    2010-02-01

    This study compared the central effects of ghrelin and leptin on body and bone marrow adiposity and gene expression in adipose tissue and bone marrow. Male Sprague-Dawley rats were injected intracerebroventricular (ICV) twice daily with control, 66 ng ghrelin (G66), 330 ng ghrelin (G330), or 5 μg leptin (L5) for 5 days. Food intake (FI) and body weight (BW) were measured daily. Gene expression in adipose tissue and bone marrow was assessed using RT-PCR. Leptin reduced FI (P < 0.05) and BW (P < 0.05), whereas ghrelin increased BW (P < 0.05) without affecting FI. Leptin decreased fat pad weights, whereas ghrelin (G330) increased fat pad weights (P < 0.05). In epididymal adipose tissue, leptin increased expression of lipolysis marker ADRB2 and thermogenesis marker MFN2 and decreased expression of adipogenic markers, FASN, SLC2A4, and SCD1, whereas ghrelin increased expression of FASN and SCD1. Leptin decreased bone marrow adipocyte size and number; however, ghrelin had no effect on these parameters. In whole bone marrow, leptin decreased expression of FASN and SCD1 and increased expression of DLK1, whereas ghrelin (G330) decreased expression of COL1A1. Thus, leptin induces similar changes in bone marrow and adipose tissue gene expression, reflecting the decreased adiposity in both compartments.

  19. Ghrelin and gastrointestinal stromal tumors

    Science.gov (United States)

    Zhu, Chang-Zhen; Liu, Dong; Kang, Wei-Ming; Yu, Jian-Chun; Ma, Zhi-Qiang; Ye, Xin; Li, Kang

    2017-01-01

    Ghrelin, as a kind of multifunctional protein polypeptide, is mainly produced in the fundus of the stomach and can promote occurrence and development of many tumors, including gastrointestinal tumors, which has been proved by the relevant researches. Most gastrointestinal stromal tumors (GISTs, about 80%), as the most common mesenchymal tumor, also develop in the fundus. Scientific research has confirmed that ghrelin, its receptors and mRNA respectively can be found in GISTs, which demonstrated the existence of a ghrelin autocrine/paracrine loop in GIST tissues. However, no reports to date have specified the mechanism whether ghrelin can promote the occurrence and development of GISTs. Studies of pulmonary artery endothelial cells in a low-oxygen environment and cardiac muscle cells in an ischemic environment have shown that ghrelin can activate the phosphatidylinositol 3-kinase/AKT/mammalian target of rapamycin (PI3K/AKT/mTOR) signaling pathway. Moreover, some studies of GISTs have confirmed that activation of the PI3K/AKT/mTOR pathway can indeed promote the growth and progression of GISTs. Whether ghrelin is involved in the development or progression of GISTs through certain pathways remains unknown. Can we find a new target for the treatment of GISTs? This review explores and summaries the relationship among ghrelin, the PI3K/AKT/mTOR pathway and the development of GISTs.

  20. Leptin, ghrelin, and endocannabinoids

    DEFF Research Database (Denmark)

    Støving, René Klinkby; Andries, Alin; Brixen, Kim;

    2008-01-01

    Anorexia nervosa (AN) has the highest mortality rate between psychiatric disorders, and evidence for managing it is still very limited. So far, pharmacological treatment has focused on a narrow range of drugs and only a few controlled studies have been performed. Furthermore, the studies have been...... molecular targets to control eating behavior has emerged. This review focuses on recent advances in three important signal systems: leptin, ghrelin, and endocannabinoids toward the identification of potential therapeutical breakthroughs in AN. Our review of the current literature shows that leptin may have...

  1. Oxytocin and dopamine stimulate ghrelin secretion by the ghrelin-producing cell line, MGN3-1 in vitro.

    OpenAIRE

    Iwakura, Hiroshi; Ariyasu, Hiroyuki; Hosoda, Hiroshi; Yamada, Go; Hosoda, Kiminori; Nakao, Kazuwa; Kangawa, Kenji; Akamizu, Takashi

    2011-01-01

    To understand the physiological role of ghrelin, it is crucial to study both the actions of ghrelin and the regulation of ghrelin secretion. Although ghrelin actions have been extensively revealed, the direct factors regulating ghrelin secretion by ghrelin-producing cells (X/A-like cells), however, is not fully understood. In this study, we examined the effects of peptide hormones and neurotransmitters on in vitro ghrelin secretion by the recently developed ghrelin-producing cell line MGN3-1....

  2. Production of ghrelin by the stomach of patients with gastric cancer.

    Science.gov (United States)

    Kizaki, Junya; Aoyagi, Keishiro; Sato, Takahiro; Kojima, Masayasu; Shirouzu, Kazuo

    2014-01-01

    Poor nutrition and weight loss are important factors contributing to poor quality of life (QOL) after gastrectomy in patients with gastric cancer. Ghrelin is a hormone produced by the stomach that, plays a role in appetite increase and fat storage. The present study aims to clarify the location of ghrelin mRNA in the stomach, changes in blood ghrelin concentrations after gastrectomy and whether or not they are associated with the reconstruction method in patients with gastric cancer. We collected seven normal mucosa samples from different parts of six totally resected stomachs with gastric cancer. We extracted RNA from the normal mucosa, synthesized cDNA from total RNA (1 μg), and then quantified ghrelin mRNA using quantitative real-time polymerase chain reaction (Q-PCR). Ghrelin blood concentrations were measured using enzyme-linked immunosorbent assay (ELISA) kits in 74 patients with gastric cancer (total gastrectomy (TG), n=23; distal gastrectomy (DG), n=30; proximal gastrectomy (PG), n=11; pylorus preserving gastrectomy (PPG), n=10). In order, the ghrelin gene was expressed most frequently in the gastric body, followed by the fornix, cardia, antrum and pylorus ring. Blood ghrelin concentrations after surgery similarly changed in all groups. The average blood ghrelin concentrations were significantly higher in the DG and PPG groups than in the TG group on postoperative days (POD) 1, 7, 30, 90 and 180. However, blood ghrelin concentrations did not significantly differ between the DG and TG groups on POD 270 and 360. Cells that produce ghrelin are supposed to be located mostly in the fundic gland of the stomach. We speculate that the production of ghrelin from other organs increases from around nine months after total gastrectomy. Therefore, evaluating the nutritional status and the weight of patients at nine months after total gastrectomy is important to help these patients improve their QOL.

  3. Ghrelin stimulates gastric emptying and hunger in normal-weight humans

    DEFF Research Database (Denmark)

    Levin, F; Edholm, T; Schmidt, P T;

    2006-01-01

    CONTEXT: Ghrelin is produced primarily by enteroendocrine cells in the gastric mucosa and increases gastric emptying in patients with gastroparesis. MAIN OBJECTIVE: The objective of the study was to evaluate the effect of ghrelin on gastric emptying, appetite, and postprandial hormone secretion...

  4. Ghrelin Cells in the Gastrointestinal Tract

    Directory of Open Access Journals (Sweden)

    Ichiro Sakata

    2010-01-01

    Full Text Available Ghrelin is 28-amino-acid peptide that was discovered from the rat and human stomach in 1999. Since the discovery of ghrelin, various functions of ghrelin, including growth hormone release, feeding behavior, glucose metabolism, memory, and also antidepressant effects, have been studied. It has also been reported that ghrelin in the gastrointestinal tract has an important physiological effect on gastric acid secretion and gastrointestinal motility. Ghrelin has a unique structure that is modified by O-acylation with n-octanoic acid at third serine residues, and this modification enzyme has recently been identified and named ghrelin O-acyl transferase (GOAT. Ghrelin is considered to be a gut-brain peptide and is abundantly produced from endocrine cells in the gastrointestinal mucosa. In the gastrointestinal tract, ghrelin cells are most abundant in the stomach and are localized in gastric mucosal layers. Ghrelin cells are also widely distributed throughout the gastrointestinal tract. In addition, abundance of ghrelin cells in the gastric mucosa is evolutionally conserved from mammals to lower vertebrates, indicating that gastric ghrelin plays important roles for fundamental physiological functions. Ghrelin cells in the gastrointestinal tract are a major source of circulating plasma ghrelin, and thus understanding the physiology of these cells would reveal the biological significance of ghrelin.

  5. Effects of ghrelin injection on plasma concentrations of glucose, pancreatic hormones and cortisol in Holstein dairy cattle.

    Science.gov (United States)

    Itoh, Fumiaki; Komatsu, Tokushi; Kushibiki, Shiro; Hodate, Koichi

    2006-01-01

    Ghrelin affects not only growth hormone secretion but also nutrient utilization and metabolic hormone secretion in humans and experimental animals. The effects of ghrelin on plasma metabolic hormone and metabolite levels in domestic herbivores remain unclear despite the fact that the physiological characteristics of nutrient digestion and absorption imply specific responses to ghrelin. Therefore, the effects of ghrelin on plasma glucose, pancreatic hormones and cortisol concentrations were investigated in Holstein dairy cattle in various physiological states. Ghrelin (0.3 nmol/kg) or placebo (2% bovine serum albumin in saline) was intravenously injected in pre-ruminant calves (pre-rumen function), adult non-lactating (functional rumen) and lactating cows (functional rumen and lactation), and plasma glucose, insulin, glucagon and cortisol concentrations were then determined. Ghrelin injection increased plasma glucose concentrations in adult cows, especially in lactating cows. No hyperglycemic response was observed in pre-ruminant calves. A transient rise of insulin and glucagon levels was distinctively found in lactating cows in response to the ghrelin administration. Ghrelin injection decreased the insulin level in pre-ruminant calves. Ghrelin increased cortisol secretion independently of the physiological state. The results of the present study suggest that the effects of ghrelin on plasma glucose and pancreatic hormone levels may reflect differences in the physiological states of dairy cattle.

  6. Reconstruction-Dependent Recovery from Anorexia and Time-Related Recovery of Regulatory Ghrelin System in Gastrectomized Rats

    Directory of Open Access Journals (Sweden)

    Masaru Koizumi

    2010-01-01

    Full Text Available Gastrectomy reduces food intake and body weight (BW hampering recovery of physical conditions. It also reduces plasma levels of stomach-derived orexigenic ghrelin. This study explored changes in orexigenic ghrelin system in rats receiving total gastrectomy with Billroth II (B-II or Roux-en-Y (R-Y method. Feeding and BW were reduced by gastrectomy and subsequently recovered to a greater extent with R-Y than B-II while plasma ghrelin decreased similarly. At postoperative 12th week, ghrelin contents increased in the duodenum and pancreas, plasma ghrelin levels increased upon fasting, and ghrelin injection promoted feeding but not in earlier periods. In summary, gastrectomized rats partially recover feeding and BW, in a reconstruction-dependent manner. At 12th week, ghrelin is upregulated in extra-stomach tissues, plasma ghrelin levels are physiologically regulated, and orexigenic effect of exogenous ghrelin is restored. This time-related recovery of ghrelin system may provide a strategy for promoting feeding, BW, and thereby physical conditions in gastrectomized patients.

  7. Regulation of oxidative stress and somatostatin, cholecystokinin, apelin gene expressions by ghrelin in stomach of newborn diabetic rats.

    Science.gov (United States)

    Coskun, Zeynep Mine; Sacan, Ozlem; Karatug, Ayse; Turk, Neslihan; Yanardag, Refiye; Bolkent, Sehnaz; Bolkent, Sema

    2013-09-01

    The aim of the study was to determine whether ghrelin treatment has a protective effect on gene expression and biochemical changes in the stomach of newborn streptozotocin (STZ) induced diabetic rats. In this study, four groups of Wistar rats were used: control, ghrelin control, diabetic and diabetic+ghrelin. The rats were sacrificed after four weeks of treatment for diabetes. The gene expressions of: somatostatin, cholecystokinin, apelin and the altered active caspase-3, active caspase-8, proliferating cell nuclear antigen, were investigated in the pyloric region of the stomach and antioxidant parameters were measured in all the stomach. Although ghrelin treatment to diabetic rats lowered the stomach lipid peroxidation levels, the stomach glutathione levels were increased. Exogenous ghrelin caused an increased activities of stomach catalase, superoxide dismutase, glutathione reductase and glutathione peroxidase in diabetic rats. Numbers of somatostatin, cholecystokinin and proliferating cell nuclear antigen immunoreactive cells decreased in the diabetic+ghrelin group compared to the diabetic group. Apelin mRNA expressions were remarkably less in the diabetic+ghrelin rats than in diabetic rats. The results may indicate that ghrelin treatment has a protective effect to some extent on the diabetic rats. This protection is possibly accomplished through the antioxidant activity of ghrelin observed in type 2 diabetes. Consequently exogenous ghrelin may be a candidate for therapeutic treatment of diabetes. Copyright © 2013 Elsevier GmbH. All rights reserved.

  8. Effect of ghrelin and thyrotropin-releasing hormone on prolactin secretion in normal women.

    Science.gov (United States)

    Messini, C I; Dafopoulos, K; Chalvatzas, N; Georgoulias, P; Anifandis, G; Messinis, I E

    2010-03-01

    It is known that ghrelin stimulates the secretion of prolactin in women. The aim of this study was to examine the effect of exogenous thyrotropin-releasing hormone (TRH) on ghrelin-induced prolactin release. Ten healthy normally cycling women were studied in four menstrual cycles. The women were injected intravenously in late follicular phase (follicle size 16-17 mm) with a single dose of normal saline (cycle 1), ghrelin (1 microg/kg) (cycle 2), thyrotropin-releasing hormone (200 microg) (cycle 3), and ghrelin plus thyrotropin-releasing hormone (cycle 4). Blood samples in relation to saline or drugs injection (time 0) were taken at -15, 0, 15, 30, 45, 60, 75, 90, and 120 min. The prolactin and growth hormone responses were assessed. After ghrelin administration (cycles 2 and 4), plasma ghrelin, serum prolactin, and growth hormone levels increased rapidly, peaking at 15-30 min (psecretion markedly (pGhrelin induced a smaller prolactin increase than thyrotropin-releasing hormone (pghrelin and thyrotropin-releasing hormone induced a similar increase in prolactin levels as with thyrotropin-releasing hormone alone. No changes in growth hormone and prolactin levels were seen after saline injection. These results demonstrate that the stimulating effect of ghrelin on prolactin secretion is not additive with that of thyrotropin-releasing hormone.

  9. Ghrelin plasma levels and appetite in peritoneal dialysis patients.

    Science.gov (United States)

    Aguilera, Abelardo; Cirugeda, Antonio; Amair, Ruth; Sansone, Gabriela; Alegre, Laura; Codoceo, Rosa; Bajo, M Auxiliadora; del Peso, Gloria; Díez, Juan J; Sánchez-Tomero, José A; Selgas, Rafael

    2004-01-01

    Anorexia-associated malnutrition is a severe complication that increases mortality in peritoneal dialysis (PD) patients. Ghrelin is a recently-discovered orexigenic hormone with actions in brain and stomach. We analyzed, in 42 PD patients, the possible relationship between ghrelin and appetite regulation with regard to other orexigens [neuropeptide Y (NPY), NO3] and anorexigens [cholecystokinin (CCK), leptin, glucose-dependent insulinotropic peptide (GIP), tumor necrosis factor alpha (TNFalpha)]. All orexigens and anorexigens were determined in plasma. Eating motivation was evaluated using a visual analog scale (VAS). The patients were divided into three groups: those with anorexia (n = 12), those with obesity associated with high intake (n = 12), and those with no eating behavior disorders (n = 18). A control group of 10 healthy volunteers was also evaluated. Mean plasma levels of ghrelin were high (3618.6 +/- 1533 mg/mL), with 36 patients showing values above the normal range (anorexia had lower ghrelin and NPY levels and higher peptide-C, CCK, interleukin-1 (IL-1), TNFalpha, and GIP levels than did the other patients. Patients with anorexia also had an early satiety score and low desire and pleasure in eating on the VAS and diet survey. We observed significant positive linear correlations between ghrelin and albumin (r = 0.43, p anorexia show relatively lower ghrelin plasma levels than the levels seen in obese patients or in patients with normal appetite. The role of ghrelin in appetite modulation is altered in uremic PD patients, and that alteration is possibly associated with disorders in insulin and growth hormone metabolism.

  10. Effect of Resected Gastric Fundus Fat on Ghrelin Tissue Levels: A Prospective Study.

    Science.gov (United States)

    Durmuş, Ali; Durmuş, Ilgim; Abahuni, Melis; Karatepe, Oguzhan

    2017-01-01

    Introduction: Obesity is currently an important health problem that is rapidly increasing worldwide. In recent years, the number of obesity-related surgeries has increased. The most common type of obesity-related surgery is laparoscopic sleeve gastrectomy (LSG). The aim of this study was to compare the genetic expression of the hormone ghrelin in different parts of the stomach. Materials and Methods: Nineteen obese patients who underwent LSG were examined in this study. Fat tissue from two different parts of the stomach, the fundus and the upper part of the fundus, were analysed by enzyme-linked immunosorbent assay (ELISA). The ribonucleic acid (RNA) isolation, complementary DNA (cDNA) and real-time quantitative polymerase chain reaction (RQ-PCR) techniques were applied. Additionally, a human ghrelin ELISA kit was used to measure ghrelin in obese patients. The ghrelin levels of fat tissue from the fundus and upper part of the fundus were statistically compared. Results: In all 19 patients, the average ghrelin level in the fundus was greater than 30. The average ghrelin level of the fat pad, which is located in the upper part of the fundus, was greater than 30 for 4 patients; the average level was approximately 5 in the remaining patients. A statistically significant difference in the ghrelin level was found between the fundus and the fundus fat tissue. Collection of fundus fat tissue is not routinely performed during LSG. However, ghrelin hormone elevation in this tissue may require collection of fundus tissue during surgery. Celsius.

  11. Exogenous ghrelin regulates proliferation and apoptosis in the hypotrophic gut mucosa of the rat.

    Science.gov (United States)

    de Segura, Ignacio A Gómez; Vallejo-Cremades, María Teresa; Lomas, Jesús; Sánchez, Miriam F; Caballero, María Isabel; Largo, Carlota; De Miguel, Enrique

    2010-04-01

    Ghrelin is the natural endogenous ligand for growth hormone secretagogue receptors. This peptide regulates energy homeostasis and expenditure and is a potential link between gut absorptive function and growth. We hypothesized that ghrelin may induce a proliferative and antiapoptotic action promoting the recovery of the hypotrophic gut mucosa. Therefore, the aim of the study was to determine the action of exogenous ghrelin following gut mucosal hypotrophia in rats fed an elemental diet. An elemental diet provides readily absorbable simple nutrients and is usually given to patients with absorptive dysfunction. Male Wistar rats (n = 48) were fed the elemental diet for one week to induce mucosal hypotrophy and then treated for another week with systemic ghrelin and pair-fed with either a normoproteic or hyperproteic isocaloric liquid diet. Another group received a standard diet instead of the elemental diet and served as control (normotrophy). The elemental diet induced intestinal hypotrophia characterized by decreased proliferation in the ileum and increased apoptosis in jejunum and ileum. Ghrelin administration restored normal levels of proliferation in the ileum and apoptosis in the jejunum, with partial apoptosis restoration in the ileum. Ghrelin levels in plasma and fundus were increased in all groups, although the highest levels were found in rats treated with exogenous ghrelin. Ghrelin administration has a positive effect in the hypotrophic gut, regulating both proliferation and apoptosis towards a physiological balance counteracting the negative changes induced by an elemental diet in the intestines.

  12. What is the general action of ghrelin for vertebrates? - comparisons of ghrelin's effects across vertebrates.

    Science.gov (United States)

    Kaiya, Hiroyuki; Kangawa, Kenji; Miyazato, Mikiya

    2013-01-15

    Ten years and more passed since ghrelin was discovered. Various physiological actions of ghrelin have been documented in both mammalian and nonmammalian vertebrates. Do these actions have any commonality? In this review, we focused on several effects of ghrelin, and compared the effect across vertebrates. We would like to discuss possible general function of ghrelin in vertebrates.

  13. Helicobacter pylori Test

    Science.gov (United States)

    ... urease test (RUT) for H. pylori Formal name: Helicobacter pylori Related tests: Gastrin At a Glance Test Sample ... else I should know? How is it used? Helicobacter pylori testing is used to diagnose an infection due ...

  14. Fasting levels of ghrelin covary with the brain response to food pictures.

    Science.gov (United States)

    Kroemer, Nils B; Krebs, Lena; Kobiella, Andrea; Grimm, Oliver; Pilhatsch, Maximilian; Bidlingmaier, Martin; Zimmermann, Ulrich S; Smolka, Michael N

    2013-09-01

    Ghrelin figures prominently in the regulation of appetite in normal-weighed individuals. The apparent failure of this mechanism in eating disorders and the connection to addictive behavior in general demand a deeper understanding of the endogenous central-nervous processes related to ghrelin. Thus, we investigated processing of pictures showing palatable food after overnight fasting and following a standardized caloric intake (i.e. a 75-g oral glucose tolerance test) using functional magnetic resonance imaging and correlated it with blood plasma levels of ghrelin. Twenty-six healthy female and male volunteers viewed food and control pictures in a block design and rated their appetite after each block. Fasting levels of ghrelin correlated positively with food-cue reactivity in a bilateral network of visual processing-, reward- and taste-related regions, including limbic and paralimbic regions. Notably, among those regions were the hypothalamus and the midbrain where ghrelin receptors are densely concentrated. In addition, high fasting ghrelin levels were associated with stronger increases of subjective appetite during the food-cue-reactivity task. In conclusion, brain activation and subjective appetite ratings suggest that ghrelin elevates the hedonic effects of food pictures. Thereby, fasting ghrelin levels may generally enhance subjective craving when confronted with reward cues.

  15. Jejunal administration of glucose enhances acyl ghrelin suppression in obese humans.

    Science.gov (United States)

    Tamboli, Robyn A; Sidani, Reem M; Garcia, Anna E; Antoun, Joseph; Isbell, James M; Albaugh, Vance L; Abumrad, Naji N

    2016-07-01

    Ghrelin is a gastric hormone that stimulates hunger and worsens glucose metabolism. Circulating ghrelin is decreased after Roux-en-Y gastric bypass (RYGB) surgery; however, the mechanism(s) underlying this change is unknown. We tested the hypothesis that jejunal nutrient exposure plays a significant role in ghrelin suppression after RYGB. Feeding tubes were placed in the stomach or jejunum in 13 obese subjects to simulate pre-RYGB or post-RYGB glucose exposure to the gastrointestinal (GI) tract, respectively, without the confounding effects of caloric restriction, weight loss, and surgical stress. On separate study days, the plasma glucose curves obtained with either gastric or jejunal administration of glucose were replicated with intravenous (iv) infusions of glucose. These "isoglycemic clamps" enabled us to determine the contribution of the GI tract and postabsorptive plasma glucose to acyl ghrelin suppression. Plasma acyl ghrelin levels were suppressed to a greater degree with jejunal glucose administration compared with gastric glucose administration (P 0.05). Direct exposure of the proximal jejunum to glucose increases acyl ghrelin suppression independent of circulating glucose levels. The enhanced suppression of acyl ghrelin after RYGB may be due to a nutrient-initiated signal in the jejunum that regulates ghrelin secretion.

  16. Relation Between Ghrelin Hormone Levels and Bone Mineral Density in Normal Adults

    Directory of Open Access Journals (Sweden)

    Y Naghiaee

    2011-08-01

    Full Text Available Introduction: Ghrelin hormone is a polypeptide with 28 amino acids that is secreted along the gastrointestinal tract, mainly in fundus of stomach. Some physiological functions of ghrelin include increase of appetite and food intake, energy balance, stimulation of growth hormone secretion and heart output and decrease in blood pressure. Recently, relation of ghrelin and bone mineral density has been considered. Methods: This descriptive study included 33 adult persons above 20 years of age. Bone mineral density was determined with dual energy x-ray absorptiometry in femur and lumbar regions. T-score over than -1 was considered as normal case. Ghrelin levels were determined by ELISA method. Results: The mean of age, body mass index and serum ghrelin were 40±10.6years, 27±3.6 kg/m² and 100.5±128 pg/ml, respectively. Correlation of ghrelin and variables was not statistically significant except weight (p=0.05. Conclusion: Range of serum ghrelin levels varies with age. In the present research, there was no relationship between ghrelin levels and bone mineral density in femur and lumbar regions. More studies with larger number of samples are proposed.

  17. Metformin directly inhibits ghrelin secretion through AMP-activated protein kinase in rat primary gastric cells.

    Science.gov (United States)

    Gagnon, J; Sheppard, E; Anini, Y

    2013-03-01

    The antidiabetic drug Metformin causes weight loss in both diabetic and non-diabetic individuals. Metformin treatment is also associated with lower circulating levels of the orexigenic hormone ghrelin. To test whether Metformin directly affects ghrelin cells, rat primary stomach cells were treated with Metformin and the levels of ghrelin secretion, proghrelin gene expression and activation of adenosine monophosphate-activated protein kinase (AMPK) were examined. Metformin significantly reduced ghrelin secretion and proghrelin mRNA production and both these effects were blocked by co-incubation with the AMPK inhibitor compound C. Furthermore, the AMPK activator 5-amino-1-β-D-ribofuranosyl-imidazole-4-carboxamide (AICAR) significantly inhibited ghrelin secretion. Additionally, ghrelin cells were shown to express AMPK. Finally, Metformin treatment caused a significant increase in the level of phosphorylated (active) AMPK. Our results show that Metformin directly inhibits stomach ghrelin production and secretion through AMPK. This reduction in ghrelin secretion may be one of the key components in Metformin's mechanism of weight loss.

  18. Effects of ghrelin on growth hormone secretion in vivo in ruminants.

    Science.gov (United States)

    Hashizume, Tsutomu; Horiuchi, Mami; Nonaka, Sumie; Kasuya, Etsuko; Kojima, Masayasu; Hosoda, Hiroshi; Kangawa, Kenji

    2005-03-15

    Ghrelin, a novel endogenous growth hormone (GH) secretagogue, has been shown to exert very potent and specific GH-releasing activity in rats and humans. However, little is known about its GH-releasing activity and endocrine effects in domestic animals. To clarify the effect of ghrelin on GH secretion in vivo in ruminants, plasma GH responses to intra-arterial and intra-hypothalamic injections of rat ghrelin (rGhrelin) were examined in goats and cattle. The intra-arterial injection of 1 microg/kg BW of rGhrelin in ovariectomized goats failed to stimulate GH release, however, a dosage of 3 microg/kg BW significantly increased plasma GH concentrations (Pghrelin into the medial basal hypothalamus (arcuate nucleus) significantly stimulated the release of GH in male calves (Pghrelin stimulates GH release in ruminants.

  19. Importance of constitutive activity and arrestin-independent mechanisms for intracellular trafficking of the ghrelin receptor

    DEFF Research Database (Denmark)

    Holliday, Nicholas D; Holst, Birgitte; Rodionova, Elena A

    2007-01-01

    . Furthermore the interaction between phosphorylated receptors and beta-arrestin adaptor proteins has been examined. Replacement of the FLAG-tagged GhrelinR C tail with the equivalent GPR39 domain (GhR-39 chimera) preserved G(q) signaling. However in contrast to the GhrelinR, GhR-39 receptors exhibited no basal...... and substantially decreased agonist-induced internalization in transiently transfected HEK293 cells. Internalized GhrelinR and GhR-39 were predominantly localized to recycling compartments, identified with transferrin and the monomeric G proteins Rab5 and Rab11. Both the inverse agonist [d-Arg(1), d-Phe(5), d-Trp(7....... In contrast, agonist-stimulated GhrelinRs recruited the clathrin adaptor green fluorescent protein-tagged beta-arrestin2 to endosomes, coincident with increased receptor phosphorylation. Thus, GhrelinR internalization to recycling compartments depends on C-terminal motifs and constitutive activity...

  20. Comparative analysis reveals loss of the appetite-regulating peptide hormone ghrelin in falcons.

    Science.gov (United States)

    Seim, Inge; Jeffery, Penny L; Herington, Adrian C; Chopin, Lisa K

    2015-05-15

    Ghrelin and leptin are key peripherally secreted appetite-regulating hormones in vertebrates. Here we consider the ghrelin gene (GHRL) of birds (class Aves), where it has been reported that ghrelin inhibits rather than augments feeding. Thirty-one bird species were compared, revealing that most species harbour a functional copy of GHRL and the coding region for its derived peptides ghrelin and obestatin. We provide evidence for loss of GHRL in saker and peregrine falcons, and this is likely to result from the insertion of an ERVK retrotransposon in intron 0. We hypothesise that the loss of anorexigenic ghrelin is a predatory adaptation that results in increased food-seeking behaviour and feeding in falcons.

  1. Low glucose-induced ghrelin secretion is mediated by an ATP-sensitive potassium channel.

    Science.gov (United States)

    Oya, Manami; Kitaguchi, Tetsuya; Harada, Kazuki; Numano, Rika; Sato, Takahiro; Kojima, Masayasu; Tsuboi, Takashi

    2015-07-01

    Ghrelin is synthesized in X/A-like cells of the gastric mucosa, which plays an important role in the regulation of energy homeostasis. Although ghrelin secretion is known to be induced by neurotransmitters or hormones or by nutrient sensing in the ghrelin-secreting cells themselves, the mechanism of ghrelin secretion is not clearly understood. In the present study, we found that changing the extracellular glucose concentration from elevated (25  mM) to optimal (10 mM) caused an increase in the intracellular Ca2+ concentration ([Ca2+]i) in ghrelin-secreting mouse ghrelinoma 3-1 (MGN3-1) cells (n=32, Pghrelin secretion (n≥3, Pghrelin secretion (n≥3, Pghrelin secretion (n≥5, Pghrelin secretion in MGN3-1 cells.

  2. Acipimox during exercise points to an inhibitory feedback of GH on ghrelin secretion in bulimic and healthy women.

    Science.gov (United States)

    Nedvidkova, Jara; Smitka, Kvido; Papezova, Hana; Vondra, Karel; Hill, Martin; Hainer, Vojtech

    2011-02-25

    Ghrelin is predominantly produced by the stomach and the growth hormone (GH)-ghrelin feedback loop between the stomach and the pituitary gland has recently been suggested. The disruption of the gut-brain axis might be involved in bulimia nervosa (BN). We investigated responses of plasma GH, ghrelin, and neuropeptide Y (NPY) concentrations to exercise or to exercise after the administration of the antilipolytic drug Acipimox (Aci) in seven BN patients and seven healthy women (C). Aci was administered 1h before exercise (45 min, 2 W/kg of lean body mass/LBM/). Ghrelin, GH, NPY, free fatty acids (FFA) and glycerol plasma levels were measured during the test using commercial kits. The exercise induced an increase in plasma GH, NPY and FFA in both groups and a decrease in plasma ghrelin levels only in BN patients. Exercise after Aci administration resulted in an increase in plasma GH, and a decrease in plasma ghrelin in both groups; NPY increased more in BN patients. Exercise-induced FFA increase was depressed after Aci. We conclude that the Aci-induced suppression in plasma ghrelin levels during exercise in both groups suggests a negative feedback of GH on ghrelin secretion. Observed changes in plasma FFA levels were not related to changes in GH and ghrelin levels. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Interleukin-1 beta-induced anorexia is reversed by ghrelin.

    Science.gov (United States)

    Gonzalez, Patricia Verónica; Cragnolini, Andrea Beatriz; Schiöth, Helgi Birgir; Scimonelli, Teresa Nieves

    2006-12-01

    Interleukins, in particular interleukin-1beta (IL-1beta), reduce food intake after peripheral and central administration, which suggests that they contribute to anorexia during various infectious, neoplastic, and autoimmune diseases. On the other hand, ghrelin stimulates food intake by acting on the central nervous system (CNS) and is considered an important regulator of food intake in both rodents and humans. In the present study, we investigated if ghrelin could reverse IL-1beta-induced anorexia. Intracerebroventricular (i.c.v.) injection of 15, 30 or 45 ng/microl of IL-1beta caused significant suppression of food intake in 20 h fasting animals. This effect lasted for a 24h period. Ghrelin (0.15 nmol or 1.5 nmol/microl) produced a significant increase in cumulative food intake in normally fed animals. However, it did not alter food intake in 20 h fasting animals. Central administration of ghrelin reduced the anorexic effect of IL-1beta (15 ng/microl). The effect was observed 30 min after injection and lasted for the next 24h. This study provides evidence that ghrelin is an orexigenic peptide capable of antagonizing IL-1beta-induced anorexia.

  4. Ghrelin attenuates gastrointestinal epithelial damage induced by doxorubicin

    Institute of Scientific and Technical Information of China (English)

    Mohamed A Fahim; Hazem Kataya; Rkia El-Kharrag; Dena AM Amer; Basel al-Ramadi; Sherif M Karam

    2011-01-01

    AIM: To examine the influence of ghrelin on the regenerative potential of gastrointestinal (GI) epithelium.METHODS: Damage to GI epithelium was induced in mice by two intravenous injections of doxorubicin (10 and 6 mg/kg). Some of the doxorubicin-treated mice received a continuous subcutaneous infusion of ghrelin (1.25 μg/h) for 10 d via implanted mini-osmotic pumps. To label dividing stem cells in the S-phase of the cell cycle, all mice received a single intraperitoneal injection of 5'-bromo-2'-deoxyuridine (BrdU) one hour before sacrifice. The stomach along with the duodenum were then removed and processed for histological examination and immunohistochemistry using anti-BrdU antibody. RESULTS: The results showed dramatic damage to the GI epithelium 3 d after administration of chemotherapy which began to recover by day 10. In ghrelin-treated mice, attenuation of GI mucosal damage was evident in the tissues examined post-chemotherapy. Immunohistochemical analysis showed an increase in the number of BrdU-labeled cells and an alteration in their distribution along the epithelial lining in response to damage by doxorubicin. In mice treated with both doxorubicin and ghrelin, the number of BrdU-labeled cells was reduced when compared with mice treated with doxorubicin alone. CONCLUSION: The present study suggests that ghrelin enhances the regenerative potential of the GI epithelium in doxorubicin-treated mice, at least in part, by modulating cell proliferation.

  5. A functional polymorphism T309G in MDM2 gene promoter, intensified by Helicobacter pylori lipopolysaccharide, is associated with both an increased susceptibility and poor prognosis of gastric carcinoma in Chinese patients.

    Science.gov (United States)

    Pan, Xiaolin; Li, Yuqin; Feng, Jin; Wang, Xiaoyong; Hao, Bo; Shi, Ruihua; Zhang, Guoxin

    2013-03-18

    Studies on the association between MDM2 SNP309 (T > G) and gastric cancer have reported conflicting results. Thus, the aim of this study was to investigate whether MDM2 SNP309 is associated with susceptibility and prognosis of gastric carcinoma in Chinese patients. Total of 574 gastric carcinoma cases and 574 age- and sex-matched healthy controls were included. MDM2 polymorphism was detected by PCR- RFLP and infection of Helicobacter pylori (H. pylori) by a validated serology test. The functionality of MDM2 SNP309, with or without H. pylori lipopolysaccharide (LPS), was examined by dual-luciferase assay. Kaplan-Meier survival curves were used to evaluate survival. Additional, a meta-analysis was conducted to verity the findings. MDM2 SNP309G/G genotype was associated with an increased risk of gastric carcinoma when compared with T/T genotype or T carriers (both P gastric carcinoma risk. SNP309G/G was identified as an independent marker of poor overall survival of carcinoma. In vitro, the luciferase assay further showed an increased transcriptional activity of SNP309G allele compared with SNP309T allele, and the function of polymorphism T309G in MDM2 gene promoter was intensified by H. pylori LPS. Pooled results from the meta-analysis confirmed that SNP309G/G genotype had a significantly increased risk of gastric carcinoma compared with T/T genotype or T carriers, consistent with the case-control findings. MDM2 SNP309G allele is associated with an increased risk and poor prognosis of gastric carcinoma in Chinese patients. Additional, there is a joint effect of MDM2 SNP309G/G allele and H. pylori infection on gastric carcinoma development, which may attribute to H. pylori LPS.

  6. Novel Molecular Aspects of Ghrelin and Leptin in the Control of Adipobiology and the Cardiovascular System

    Directory of Open Access Journals (Sweden)

    Amaia Rodríguez

    2014-03-01

    Full Text Available Ghrelin and leptin show opposite effects on energy balance. Ghrelin constitutes a gut hormone that is secreted to the bloodstream in two major forms, acylated and desacyl ghrelin. The isoforms of ghrelin not only promote adiposity by the activation of hypothalamic orexigenic neurons but also directly stimulate the expression of several fat storage-related proteins in adipocytes, including ACC, FAS, LPL and perilipin, thereby stimulating intracytoplasmic lipid accumulation. Moreover, both acylated and desacyl ghrelin reduce TNF-α-induced apoptosis and autophagy in adipocytes, suggesting an anti-inflammatory role of ghrelin in human adipose tissue. On the other hand, leptin is an adipokine with lipolytic effects. In this sense, leptin modulates via PI3K/Akt/mTOR the expression of aquaglyceroporins such as AQP3 and AQP7 that facilitate glycerol efflux from adipocytes in response to the lipolytic stimuli via its translocation from the cytosolic fraction (AQP3 or lipid droplets (AQP7 to the plasma membrane. Ghrelin and leptin also participate in the homeostasis of the cardiovascular system. Ghrelin operates as a cardioprotective factor with increased circulating acylated ghrelin concentrations in patients with left ventricular hypertrophy (LVH causally related to LV remodeling during the progression to LVH. Additionally, leptin induces vasodilation by inducible NO synthase expression (iNOS in the vascular wall. In this sense, leptin inhibits the angiotensin II-induced Ca2+ increase, contraction and proliferation of VSMC through NO-dependent mechanisms. Together, dysregulation of circulating ghrelin isoforms and leptin resistance associated to obesity, type 2 diabetes, or the metabolic syndrome contribute to cardiometabolic derangements observed in these pathologies.

  7. Effects of central infusion of ghrelin on food intake and plasma levels of growth hormone, luteinizing hormone, prolactin, and cortisol secretion in sheep.

    Science.gov (United States)

    Iqbal, Javed; Kurose, Yohei; Canny, Benedict; Clarke, Iain J

    2006-01-01

    Ghrelin is an endogenous ligand for the GH secretagogue/ghrelin receptor (GHS-R) and stimulates feeding behavior and GH levels in rodents and humans. A preprandial increase in plasma ghrelin levels is seen in sheep on programmed feeding, followed by a postprandial rise in plasma GH levels, but effects on food intake and endocrine function are not defined in this ruminant species. We administered ghrelin to female sheep in various modes and measured effects on voluntary food intake (VFI) and plasma levels of GH, LH, prolactin, and cortisol. Whether administered intracerebroventricularly or iv, ghrelin consistently failed to stimulate VFI. On the other hand, ghrelin invariably increased plasma GH levels and alpha,beta-diaminopropanoic acid-octanoyl3 human ghrelin was more potent than ovine ghrelin. Bolus injection of ghrelin into the third cerebral ventricle reduced plasma LH levels but did not affect levels of prolactin or cortisol. These findings suggested that the preprandial rise in plasma ghrelin that is seen in sheep on programmed feeding does not influence VFI but is likely to be important in the postprandial rise in GH levels. Thus, ghrelin does not appear to be a significant regulator of ingestive behavior in this species of ruminant but acts centrally to indirectly regulate GH and LH secretion.

  8. Expression and localization of ghrelin and its receptor in ovarian follicles during different stages of development and the modulatory effect of ghrelin on granulosa cells function in buffalo.

    Science.gov (United States)

    Gupta, M; Dangi, S S; Singh, G; Sarkar, M

    2015-01-01

    Ghrelin, a hormone predominantly found in the stomach, was recently described as a factor that controls female reproductive function. The aim of our study was to investigate the expression and localization of ghrelin and its active receptor, growth hormone secretagogue receptor type 1a (GHS-R1a) in buffalo ovarian follicles of different follicular size and to investigate role of ghrelin on estradiol (E2) secretion, aromatase (CYP19A1), proliferating cell nuclear antigen (PCNA) and apoptosis regulator Bax gene expression on granulosa cell culture. Using real time PCR and western blot, we measured gene and protein expression of examined factors. Localization was done with immunofluorescence method. Expression of ghrelin increased with follicle size with significantly highest in dominant or pre-ovulatory follicle (Pghrelin each at 1, 10 and 100ng/ml concentrations for two days after obtaining 75-80 per cent confluence. Ghrelin treatment significantly (Psecretion, CYP19A1 expression, apoptosis and promoted cell proliferation. In conclusion, this study provides novel evidence for the presence of ghrelin and receptor GHS-R1a in ovarian follilcles and modulatory role of ghrelin on granulosa cell function in buffalo.

  9. Ghrelin: much more than a hunger hormone

    Science.gov (United States)

    Ghrelin is a multifaceted gut hormone that activates its receptor, growth hormone secretagogue receptor (GHS-R). Ghrelin's hallmark functions are its stimulatory effects on growth hormone release, food intake and fat deposition. Ghrelin is famously known as the 'hunger hormone'. However, ample recen...

  10. [Helicobacter pylori and Arteriosclerosis].

    Science.gov (United States)

    Matsui, Teruaki

    2011-03-01

    Helicobacter pylori (H. pylori) infection-related diseases are known to include gastritis, gastric and duodenal ulcer, gastric cancer, gastric MALT lymphoma, idiopathic thrombocytopenic purpura, iron-deficient anemia, urticaria, reflux esophagitis, and some lifestyle-related diseases. It is indicated that homocysteine involved with arteriosclerosis induces lifestyle-related diseases. Homocysteine is decomposed to methionine and cysteine (useful substances) in the liver, through the involvement of vitamin B₁₂ (VB₁₂) and folic acid. However, deficiency of VB₁₂ and folic acid induces an increase in unmetabolized homocysteine stimulating active oxygen and promoting arteriosclerosis. VB₁₂ and folic acid are activated by the intrinsic factors of gastric parietal cells and gastric acid. The question of whether homocysteine, as a trigger of arteriosclerosis, was influenced by H. pylori infection was investigated. H. pylori infection induces atrophy of the gastric mucosa, and the function of parietal cells decreases with the atrophy to inactivate its intrinsic factor. The inactivation of the intrinsic factor causes a deficiency of VB₁₂ and folic acid to increase homocysteine's chances of triggering arteriosclerosis. The significance and usefulness of H. pylori eradication therapy was evaluated for its ability to prevent arteriosclerosis that induces lifestyle-related diseases. Persons with positive and negative results of H. pylori infection were divided into a group of those aged 65 years or more (early and late elderly) and a group of those under 65 years of age, and assessed for gastric juice. For twenty-five persons from each group who underwent gastrointestinal endoscopy, the degree of atrophy of the gastric mucosa was observed. Blood homocysteine was measured as a novel index of arteriosclerosis, as well as VB₁₂ and folic acid that affect the metabolism of homocysteine, and then activated by gastric acid and intrinsic factors. Their

  11. Pathogenesis of Helicobacter pylori infection.

    Science.gov (United States)

    Hofman, Paul; Waidner, Barbara; Hofman, Véronique; Bereswill, Stefan; Brest, Patrick; Kist, Manfred

    2004-01-01

    Research in the last year has provided new insights into the function of the the cag-associated type IV secretion system and the vacuolating toxin VacA. A quite new aspect was disclosed by the finding that Helicobacter pylori in Mongolian gerbils colonizes a very distinct topology in the gastric mucous layer, obviously providing optimal conditions for long-term survival. Further research activities focused on H. pylori ammonia and metal metabolism as well as on bacterial stress defence mechanisms. Differential expression of approximately 7% of the bacterial genome was found at low pH suggesting that H. pylori has evolved a multitude of acid-adaptive mechanisms. VacA was shown to interrupt phagosome maturation in macrophage cell lines as well as to modulate and interfere with T lymphocyte immunological functions. Gastric mucosa as well as the H. pylori-infected epithelial cell line AGS strongly express IL-8 receptor A and B, which might contribute to the augmentation of the inflammatory response. Accumulating evidence implicates genetic variation in the inflammatory response to H. pylori in the etiology of the increased risk of gastric cancer after H. pylori infection. The chronic imbalance between apoptosis and cell proliferation is the first step of gastric carcinogenesis. In this regard, it was demonstrated that coexpression of two H. pylori proteins, CagA and HspB, in AGS cells, caused an increase in E2F transcription factor, cyclin D3, and phosphorylated retinoblastoma protein. Taken together, we now have a better understanding of the role of different virulence factors of H. pylori. There is still a lot to be learned, but the promising discoveries summarized here, demonstrate that the investigation of the bacterial survival strategies will give novel insights into pathogenesis and disease development.

  12. Extraintestinal manifestations of Helicobacter pylori: A concise review

    OpenAIRE

    Wong, Frank; Rayner-Hartley, Erin; Byrne, Michael F

    2014-01-01

    Helicobacter pylori (H. pylori) infection has been clearly linked to peptic ulcer disease and some gastrointestinal malignancies. Increasing evidence demonstrates possible associations to disease states in other organ systems, known as the extraintestinal manifestations of H. pylori. Different conditions associated with H. pylori infection include those from hematologic, cardiopulmonary, metabolic, neurologic, and dermatologic systems. The aim of this article is to provide a concise review of...

  13. A link between FTO, ghrelin, and impaired brain food-cue responsivity.

    Science.gov (United States)

    Karra, Efthimia; O'Daly, Owen G; Choudhury, Agharul I; Yousseif, Ahmed; Millership, Steven; Neary, Marianne T; Scott, William R; Chandarana, Keval; Manning, Sean; Hess, Martin E; Iwakura, Hiroshi; Akamizu, Takashi; Millet, Queensta; Gelegen, Cigdem; Drew, Megan E; Rahman, Sofia; Emmanuel, Julian J; Williams, Steven C R; Rüther, Ulrich U; Brüning, Jens C; Withers, Dominic J; Zelaya, Fernando O; Batterham, Rachel L

    2013-08-01

    Polymorphisms in the fat mass and obesity-associated gene (FTO) are associated with human obesity and obesity-prone behaviors, including increased food intake and a preference for energy-dense foods. FTO demethylates N6-methyladenosine, a potential regulatory RNA modification, but the mechanisms by which FTO predisposes humans to obesity remain unclear. In adiposity-matched, normal-weight humans, we showed that subjects homozygous for the FTO "obesity-risk" rs9939609 A allele have dysregulated circulating levels of the orexigenic hormone acyl-ghrelin and attenuated postprandial appetite reduction. Using functional MRI (fMRI) in normal-weight AA and TT humans, we found that the FTO genotype modulates the neural responses to food images in homeostatic and brain reward regions. Furthermore, AA and TT subjects exhibited divergent neural responsiveness to circulating acyl-ghrelin within brain regions that regulate appetite, reward processing, and incentive motivation. In cell models, FTO overexpression reduced ghrelin mRNA N6-methyladenosine methylation, concomitantly increasing ghrelin mRNA and peptide levels. Furthermore, peripheral blood cells from AA human subjects exhibited increased FTO mRNA, reduced ghrelin mRNA N6-methyladenosine methylation, and increased ghrelin mRNA abundance compared with TT subjects. Our findings show that FTO regulates ghrelin, a key mediator of ingestive behavior, and offer insight into how FTO obesity-risk alleles predispose to increased energy intake and obesity in humans.

  14. Ghrelin-Derived Peptides: A Link between Appetite/Reward, GH Axis, and Psychiatric Disorders?

    Science.gov (United States)

    Labarthe, Alexandra; Fiquet, Oriane; Hassouna, Rim; Zizzari, Philippe; Lanfumey, Laurence; Ramoz, Nicolas; Grouselle, Dominique; Epelbaum, Jacques; Tolle, Virginie

    2014-01-01

    Psychiatric disorders are often associated with metabolic and hormonal alterations, including obesity, diabetes, metabolic syndrome as well as modifications in several biological rhythms including appetite, stress, sleep-wake cycles, and secretion of their corresponding endocrine regulators. Among the gastrointestinal hormones that regulate appetite and adapt the metabolism in response to nutritional, hedonic, and emotional dysfunctions, at the interface between endocrine, metabolic, and psychiatric disorders, ghrelin plays a unique role as the only one increasing appetite. The secretion of ghrelin is altered in several psychiatric disorders (anorexia, schizophrenia) as well as in metabolic disorders (obesity) and in animal models in response to emotional triggers (psychological stress …) but the relationship between these modifications and the physiopathology of psychiatric disorders remains unclear. Recently, a large literature showed that this key metabolic/endocrine regulator is involved in stress and reward-oriented behaviors and regulates anxiety and mood. In addition, preproghrelin is a complex prohormone but the roles of the other ghrelin-derived peptides, thought to act as functional ghrelin antagonists, are largely unknown. Altered ghrelin secretion and/or signaling in psychiatric diseases are thought to participate in altered appetite, hedonic response and reward. Whether this can contribute to the mechanism responsible for the development of the disease or can help to minimize some symptoms associated with these psychiatric disorders is discussed in the present review. We will thus describe (1) the biological actions of ghrelin and ghrelin-derived peptides on food and drugs reward, anxiety and depression, and the physiological consequences of ghrelin invalidation on these parameters, (2) how ghrelin and ghrelin-derived peptides are regulated in animal models of psychiatric diseases and in human psychiatric disorders in relation with the GH axis.

  15. Ghrelin-derived peptides: a link between appetite/reward, GH axis and psychiatric disorders ?

    Directory of Open Access Journals (Sweden)

    Alexandra eLabarthe

    2014-10-01

    Full Text Available Psychiatric disorders are often associated with metabolic and hormonal alterations, including obesity, diabetes, metabolic syndrome as well as modifications in several biological rhythms including appetite, stress, sleep-wake cycles and secretion of their corresponding endocrine regulators.Among the gastrointestinal hormones that regulate appetite and adapt the metabolism in response to nutritional, hedonic and emotional dysfunctions, at the interface between endocrine, metabolic and psychiatric disorders, ghrelin plays a unique role as the only one increasing appetite. The secretion of ghrelin is altered in several psychiatric disorders (anorexia, schizophrenia as well as in metabolic disorders (obesity and in animal models in response to emotional triggers (psychological stress, …. but the relationship between these modifications and the physiopathology of psychiatric disorders remains unclear. Recently, a large literature showed that this key metabolic/endocrine regulator is involved in stress and reward-oriented behaviors and regulates anxiety and mood. In addition, preproghrelin is a complex prohormone but the roles of the other ghrelin-derived peptides, thought to act as functional ghrelin antagonists, are largely unknown. Altered ghrelin secretion and/or signaling in psychiatric diseases are thought to participate in altered appetite, hedonic response and reward. Whether this can contribute to the mechanism responsible for the development of the disease or can help to minimize some symptoms associated with these psychiatric disorders is discussed in the present review. We will thus describe 1 the biological actions of ghrelin and ghrelin-derived peptides on food and drugs reward, anxiety and depression, and the physiological consequences of ghrelin invalidation on these parameters, 2 how ghrelin and ghrelin-derived peptides are regulated in animal models of psychiatric diseases and in human psychiatric disorders in relation with the GH

  16. Therapeutic effect of ghrelin in the course of cerulein-induced acute pancreatitis in rats.

    Science.gov (United States)

    Warzecha, Z; Ceranowicz, P; Dembinski, A; Cieszkowski, J; Kusnierz-Cabala, B; Tomaszewska, R; Kuwahara, A; Kato, I

    2010-08-01

    Recent studies have shown that pretreatment with ghrelin exhibits protective effect in the gut. Administration of ghrelin reduces gastric mucosal damage, as well as inhibits the development of experimental pancreatitis. However, this protective effect requires administration of ghrelin before gastric or pancreatic damage and thus has a limited clinical value. The aim of present study was to assess the influence of ghrelin administered after development of acute pancreatitis on the course of this disease. Acute pancreatitis was induced by cerulein. Ghrelin was administered twice a day for 1, 2, 4, 6 or 9 days at the dose of 4, 8 or 16 nmol/kg/dose. The first dose of ghrelin was given 24 hours after last injection of cerulein. The severity of acute pancreatitis was assessed between 0 h and 10 days after cessation of cerulein administration. Administration of caerulein led to the development of acute edematous pancreatitis and maximal severity of this disease was observed 24 hours after induction of pancreatitis. Treatment with ghrelin reduced morphological signs of pancreatic damage such as pancreatic edema, leukocyte infiltration and vacuolization of acinar cells, and led to earlier regeneration of the pancreas. Also biochemical indexes of the severity of acute pancreatitis, serum activity of lipase and amylase were significantly reduced in animals treated with ghrelin. These effects were accompanied by an increase in the pancreatic DNA synthesis and a decrease in serum level of pro-inflammatory interleukin-1b. Administration of ghrelin improved pancreatic blood flow in rats with acute pancreatitis. We conclude that: (1) treatment with ghrelin exhibits therapeutic effect in caerulein-induced experimental acute pancreatitis; (2) this effect is related, at least in part, to the improvement of pancreatic blood flow, reduction in proinflammatory interleukin-1beta and stimulation of pancreatic cell proliferation.

  17. The Relation Between Laparoscopic Sleeve Gastrectomy and Ghrelin

    Directory of Open Access Journals (Sweden)

    Sema Çalapkorur

    2017-07-01

    Full Text Available Recently, obesity has become an important worldwide health problem. One of the obesity treatment alternatives is bariatric surgery methods and their efficiency is increasing from day to day. In laparoscopic Sleeve gastrectomy being a bariatric surgery method, as a result of stomach fundus excretion, levels of some hormones change. Therefore, weight losses seen after the treatment are related to these changes. Basically, it is claimed that, after laparoscopic Sleeve gastrectomy, levels of ghrelin hormones secreted by stomach fundus, being effective for appetite and getting foods change. Although there are many studies examining varieties of ghrelin levels after laparoscopic sleeve gastrectomy, there is no final judgment concerning the subject yet. In this review, in the light of literature knowledge, giving information regarding effects of laparoscopic sleeve gastrectomy on ghrelin levels is aimed.

  18. Obesity, food intake and exercise: Relationship with ghrelin

    Directory of Open Access Journals (Sweden)

    Tiryaki-Sonmez Gul

    2015-09-01

    Full Text Available Obesity, a disorder of body composition, is defined by a relative or absolute excess of body fat. In general adult population, obesity has been associated with a diverse array of adverse health outcomes, including major causes of death such as cancer, diabetes, cardiovascular disease, as well as functional impairment from problems such as osteoarthritis and sleep apnea. Ghrelin is a newly discovered peptide hormone which plays an important role in obesity. It is a powerful, endogenous orexigenic peptide and has a crucial function in appetite regulation, as well as short – and long-term energy homeostasis. In the presence of increased obesity, decreased physical activity, and high food consumption, the relationship between exercise, appetite, food intake and ghrelin levels has important implications. In this review, we discuss the effect of acute and chronic exercise performance on appetite, food intake and ghrelin and their relationships.

  19. SKF 83566 attenuates the effects of ghrelin on performance in the object location memory task.

    Science.gov (United States)

    Jacoby, Sarah M; Currie, Paul J

    2011-10-31

    Increasing research implicates ghrelin, a metabolic signaling peptide, in memory processes including acquisition, consolidation, and retention. The present study investigated the effects of ghrelin on spatial memory acquisition by utilizing the object location memory task paradigm. Given the co-expression of ghrelin and dopamine D(1) receptors within hippocampal neurons, we examined a potential interaction between these two systems on memory performance. When injected into the dorsal third ventricle (D3V) of male Sprague-Dawley rats, proximal to hippocampal tissue, ghrelin (500 pmol) increased the amount of time spent with objects in novel locations. This effect was completely reversed by the D(1) antagonist SKF 83566 (100 μg/kg IP), although when administered alone, the antagonist had no effect on task performance (10-100 μg/kg). We also examined the feeding effects of D3V ghrelin and found that the peptide reliably increased food intake (500 pmol) but that this effect was not blocked by SKF 83566 (100 μg/kg). When given alone, SKF 83566 did not alter food intake (10-100 μg/kg). Our findings indicate that, in addition to an orexigenic effect, ghrelin improves acquisition of spatial location memories. Furthermore, D(1) receptor activation is necessary for ghrelin to improve the encoding of spatial memories but does not impact the increase in food intake elicited by the peptide.

  20. Ghrelin O-Acyl Transferase: Bridging Ghrelin and Energy Homeostasis

    Directory of Open Access Journals (Sweden)

    Andrew Shlimun

    2011-01-01

    Full Text Available Ghrelin O-acyl transferase (GOAT is a recently identified enzyme responsible for the unique n-acyl modification of ghrelin, a multifunctional metabolic hormone. GOAT structure and activity appears to be conserved from fish to man. Since the acyl modification is critical for most of the biological actions of ghrelin, especially metabolic functions, GOAT emerged as a very important molecule of interest. The research on GOAT is on the rise, and several important results reiterating its significance have been reported. Notable among these discoveries are the identification of GOAT tissue expression patterns, effects on insulin secretion, blood glucose levels, feeding, body weight, and metabolism. Several attempts have been made to design and test synthetic compounds that can modulate endogenous GOAT, which could turn beneficial in favorably regulating whole body energy homeostasis. This paper will focus to provide an update on recent advances in GOAT research and its broader implications in the regulation of energy balance.

  1. Ghrelin promotes differentiation of human embryonic stem cells into cardiomyocytes

    Institute of Scientific and Technical Information of China (English)

    Jin YANG; Guo-qiang LIU; Rui WEI; Wen-fang HOU; Mei-juan GAO; Ming-xia ZHU; Hai-ning WANG; Gui-an CHEN; Tian-pei HONG

    2011-01-01

    Aim:Ghrelin is involved in regulating the differentiation of mesoderm-derived precursor cells.The aim of this study was to investigate whether ghrelin modulated the differentiation of human embryonic stem (hES) cells into cardiomyocytes and,if so,whether the effect was mediated by growth hormone secretagogue receptor 1α (GHS-R1α).Methods:Cardiomyocyte differentiation from hES cells was performed according to an embryoid body (EB)-based protocol.The cumulative percentage of beating EBs was calculated.The expression of cardiac-specific markers including cardiac troponin Ⅰ (cTnl) and α-myosin heavy chain (α-MHC) was detected using RT-PCR,real-time PCR and Western blot.The dispersed beating EBs were examined using immunofluorescent staining.Results:The percentage of beating EBs and the expression of cTnl were significantly increased after ghrelin (0.1 and 1 nmol/L) added into the differentiation medium.From 6 to 18 d of differentiation,the increased expression of cTnl and α-MHC by ghrelin (1 nmol/L)was time-dependent,and in line with the alteration of the percentages of beating EBs.Furthermore,the dispersed beating EBs were double-positively immunostained with antibodies against cTnl and α-actinin.However,blockage of GHS-R1α with its specific antagonist D-[lys3]-GHRP-6 (1 μmol/L) did not alter the effects of ghrelin on cardiomyocyte differentiation.Conclusion:Our data show that ghrelin enhances the generation of cardiomyocytes from hES cells,which is not mediated via GHS-R1α.

  2. Helicobacter pylori in gastric carcinogenesis

    Institute of Scientific and Technical Information of China (English)

    Hyo; Jun; Ahn; Dong; Soo; Lee

    2015-01-01

    Gastric cancer still is a major concern as the third most common cancer worldwide, despite declining rates of incidence in many Western countries. Helicobacter pylori(H. pylori) is the major cause of gastric carcinogenesis, and its infection insults gastric mucosa leading to theoccurrence of atrophic gastritis which progress to intestinal metaplasia, dysplasia, early gastric cancer, and advanced gastric cancer consequently. This review focuses on multiple factors including microbial virulence factors, host genetic factors, and environmental factors, which can heighten the chance of occurrence of gastric adenocarcinoma due to H. pylori infection. Bacterial virulence factors are key components in controlling the immune response associated with the induction of carcinogenesis, and cag A and vac A are the most well-known pathogenic factors. Host genetic polymorphisms contribute to regulating the inflammatory response to H. pylori and will become increasingly important with advancing techniques. Environmental factors such as high salt and smoking may also play a role in gastric carcinogenesis. It is important to understand the virulence factors, host genetic factors, and environmental factors interacting in the multistep process of gastric carcinogenesis. To conclude, prevention via H. pylori eradication and controlling environmental factors such as diet, smoking, and alcohol is an important strategy to avoid H. pylori-associated gastric carcinogenesis.

  3. Ghrelin and Ghrelin Receptor Modulation of Psychostimulant Action

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    Paul Jeff Wellman

    2013-09-01

    Full Text Available Ghrelin (GHR is an orexigenic gut peptide that modulates multiple homeostatic functions including gastric emptying, anxiety, stress, memory, feeding and reinforcement. GHR is known to bind and activate growth-hormone secretagogue receptors (termed GHR-Rs. Of interest to our laboratory has been the assessment of the impact of GHR modulation of the locomotor activation and reward/reinforcement properties of psychostimulants such as cocaine and nicotine. Systemic GHR infusions augment cocaine stimulated locomotion and conditioned place preference (CPP in rats, as does food restriction which elevates plasma ghrelin levels. Ghrelin enhancement of psychostimulant function may occur owing to a direct action on mesolimbic dopamine function or may reflect an indirect action of ghrelin on glucocorticoid pathways. Genomic or pharmacological ablation of GHR-Rs attenuates the acute locomotor-enhancing effects of nicotine, cocaine, amphetamine and alcohol and blunts the CPP induced by food, alcohol, amphetamine and cocaine in mice. The stimulant nicotine can induce CPP and like amphetamine and cocaine, repeated administration of nicotine induces locomotor sensitization in rats. Inactivation of ghrelin circuit function in rats by injection of a ghrelin receptor antagonist (e.g. JMV 2959 diminishes the development of nicotine-induced locomotor sensitization. These results suggest a key permissive role for GHR-R activity for the induction of locomotor sensitization to nicotine. Our finding that GHR-R null rats exhibit diminished patterns of responding for intracranial self-stimulation complements an emerging literature implicating central GHR circuits in drug reward/reinforcement. Finally, antagonism of GHR-Rs may represent a smoking cessation modality that not only blocks nicotine-induced reward but that also may limit weight gain after smoking cessation.

  4. Ghrelin Gene Expression in Broiler Proventriculus Tissue are Changed by Feed Restriction, Different Dietary Energy and Protein Levels

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    Shokoufe Ghazanfari

    2010-01-01

    Full Text Available Problem statement: The aim of this study was to investigate the effects of feed restriction and different energy and protein contents of diet on ghrelin gene expression in broiler chicken. Approach: Feeding programs consisted of ad libitum and feed restriction, two energy levels (3100 and 2800 kcal ME kg-1 and three protein levels (22.3, 19.3 and 16.3% CP. Feed restriction was applied during 22-32 days of age. Proventriculus samples were collected at 21, 32 and 49 days of age. Ghrelin mRNA expression in proventriculus tissue was quantitate using Real Time quantitative PCR. Results: We found that ghrelin gene expression was increased in restricted chicks compared with those fed ad libitum at 32 days of age (p = 0.09 but feed restriction had no effect on ghrelin gene expression at 49 days of age. A positive response in ghrelin gene expression was achieved by decreasing energy level in the diet at 21 days of age (pConclusion: The present study, we investigated the effects of feed restriction and different energy and protein contents of the diet on ghrelin gene expression in broiler chicken. We have characterized chicken ghrelin cDNA in proventriculus tissue in broiler chicken. We also found that ghrelin gene expression is differently suppressed by diet manipulations. Additional studies are necessary to investigate the role of nutrition on ghrelin gene expression in proventriculus tissue in broiler chicken.

  5. Intraportal infusion of ghrelin could inhibit glucose-stimulated GLP-1 secretion by enteric neural net in Wistar rat.

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    Zhang, Xiyao; Li, Wensong; Li, Ping; Chang, Manli; Huang, Xu; Li, Qiang; Cui, Can

    2014-01-01

    As a regulator of food intake and energy metabolism, the role of ghrelin in glucose metabolism is still not fully understood. In this study, we determined the in vivo effect of ghrelin on incretin effect. We demonstrated that ghrelin inhibited the glucose-stimulated release of glucagon-like peptide-1 (GLP-1) when infused into the portal vein of Wistar rat. Hepatic vagotomy diminished the inhibitory effect of ghrelin on glucose-stimulated GLP-1 secretion. In addition, phentolamine, a nonselective α receptor antagonist, could recover the decrease of GLP-1 release induced by ghrelin infusion. Pralmorelin (an artificial growth hormone release peptide) infusion into the portal vein could also inhibit the glucose-stimulated release of GLP-1. And growth hormone secretagogue receptor antagonist, [D-lys3]-GHRP-6, infusion showed comparable increases of glucose stimulated GLP-1 release compared to ghrelin infusion into the portal vein. The data showed that intraportal infusion of ghrelin exerted an inhibitory effect on GLP-1 secretion through growth hormone secretagogue receptor 1α (GHS1α receptor), which indicated that the downregulation of ghrelin secretion after food intake was necessary for incretin effect. Furthermore, our results suggested that the enteric neural net involved hepatic vagal nerve and sympathetic nerve mediated inhibition effect of ghrelin on incretin effect.

  6. Impaired postprandial fullness in Type 2 diabetic subjects is rescued by acute exercise independently of total and acylated ghrelin.

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    Knudsen, Sine H; Karstoft, Kristian; Solomon, Thomas P J

    2013-09-01

    Ghrelin levels are suppressed in obese subjects and subjects with Type 2 diabetes mellitus (T2DM). Exercise-stimulated decreases in plasma ghrelin are a proposed mediator of exercise-induced satiety in healthy subjects. However, exercise-induced satiety and the impact of impaired ghrelin levels in obesity-related disease are poorly understood. Therefore our objective was to investigate exercise-induced postprandial satiety and ghrelin responses in overweight subjects with T2DM (N = 8) and healthy controls (N = 7). Visual analog scale satiety questionnaires (assessing hunger, thirst, food that could be eaten, nausea, and fullness) and circulating levels of glucose, insulin, and total and acylated ghrelin were measured at baseline and in response to a 75 g oral glucose load, provided immediately after an aerobic exercise bout (1 h at 50% Wmax) or no exercise (rest trial), on two separate occasions. Baseline levels of total (284.4 ± 15.9 and 397.6 ± 35.2 pmol/l) and acylated ghrelin (7.9 ± 1.0 and 13.7 ± 1.2 pmol/l) were lower in subjects with T2DM compared with healthy subjects (P Exercise increased postprandial fullness in the T2DM group (P ghrelin levels were unaffected. Our data suggest that the presence of T2DM likely drives suppressed ghrelin levels and poor appetite regulation, but a single exercise bout is sufficient to restore oral glucose-induced fullness independently of ghrelin.

  7. Ghrelin Facilitates GLUT2-, SGLT1- and SGLT2-mediated Intestinal Glucose Transport in Goldfish (Carassius auratus)

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    Blanco, Ayelén Melisa; Bertucci, Juan Ignacio; Ramesh, Naresh; Delgado, María Jesús; Valenciano, Ana Isabel; Unniappan, Suraj

    2017-01-01

    Glucose homeostasis is an important biological process that involves a variety of regulatory mechanisms. This study aimed to determine whether ghrelin, a multifunctional gut-brain hormone, modulates intestinal glucose transport in goldfish (Carassius auratus). Three intestinal glucose transporters, the facilitative glucose transporter 2 (GLUT2), and the sodium/glucose co-transporters 1 (SGLT1) and 2 (SGLT2), were studied. Immunostaining of intestinal sections found colocalization of ghrelin and GLUT2 and SGLT2 in mucosal cells. Some cells containing GLUT2, SGLT1 and SGLT2 coexpressed the ghrelin/growth hormone secretagogue receptor 1a (GHS-R1a). Intraperitoneal glucose administration led to a significant increase in serum ghrelin levels, as well as an upregulation of intestinal preproghrelin, ghrelin O-acyltransferase and ghs-r1 expression. In vivo and in vitro ghrelin treatment caused a concentration- and time-dependent modulation (mainly stimulatory) of GLUT2, SGLT1 and SGLT2. These effects were abolished by the GHS-R1a antagonist [D-Lys3]-GHRP-6 and the phospholipase C inhibitor U73122, suggesting that ghrelin actions on glucose transporters are mediated by GHS-R1a via the PLC/PKC signaling pathway. Finally, ghrelin stimulated the translocation of GLUT2 into the plasma membrane of goldfish primary intestinal cells. Overall, data reported here indicate an important role for ghrelin in the modulation of glucoregulatory machinery and glucose homeostasis in fish. PMID:28338019

  8. Intraportal Infusion of Ghrelin Could Inhibit Glucose-Stimulated GLP-1 Secretion by Enteric Neural Net in Wistar Rat

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    Xiyao Zhang

    2014-01-01

    Full Text Available As a regulator of food intake and energy metabolism, the role of ghrelin in glucose metabolism is still not fully understood. In this study, we determined the in vivo effect of ghrelin on incretin effect. We demonstrated that ghrelin inhibited the glucose-stimulated release of glucagon-like peptide-1 (GLP-1 when infused into the portal vein of Wistar rat. Hepatic vagotomy diminished the inhibitory effect of ghrelin on glucose-stimulated GLP-1 secretion. In addition, phentolamine, a nonselective α receptor antagonist, could recover the decrease of GLP-1 release induced by ghrelin infusion. Pralmorelin (an artificial growth hormone release peptide infusion into the portal vein could also inhibit the glucose-stimulated release of GLP-1. And growth hormone secretagogue receptor antagonist, [D-lys3]-GHRP-6, infusion showed comparable increases of glucose stimulated GLP-1 release compared to ghrelin infusion into the portal vein. The data showed that intraportal infusion of ghrelin exerted an inhibitory effect on GLP-1 secretion through growth hormone secretagogue receptor 1α (GHS1α receptor, which indicated that the downregulation of ghrelin secretion after food intake was necessary for incretin effect. Furthermore, our results suggested that the enteric neural net involved hepatic vagal nerve and sympathetic nerve mediated inhibition effect of ghrelin on incretin effect.

  9. Effects of ghrelin on the structural complexity of exocrine pancreas tissue architecture.

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    Pantic, Igor; Nesic, Dejan; Stevanovic, Darko; Starcevic, Vesna; Pantic, Senka; Trajkovic, Vladimir

    2013-06-01

    Recent studies have shown that ghrelin increases pancreatic exocrine secretion. However, the potential effects of ghrelin on the morphology of exocrine pancreas (EP) remain unknown. In this work, using fractal analysis, we demonstrate that centrally administered ghrelin increases structural complexity and tissue disorder in rat EP. The study was carried out on a total of 40 male Wistar rats divided into four groups (n = 10): ghrelin-treated animals (average age, 1.5 months), ghrelin-treated animals (8.5 months), and controls (1.5 and 8.5 months). The pancreas tissue sections were stained with hematoxylin/eosin and visualized by light microscopy. For each animal, the average values of tissue fractal dimension, lacunarity, as well as parameters of co-occurrence matrix texture, were determined using tissue digital micrographs. The results indicate that ghrelin administration increases EP fractal dimension and textural entropy, and decreases lacunarity, regardless of the age. To our knowledge, this is the first study to investigate the effects of ghrelin on the morphological properties of pancreatic tissue, and also the first to apply fractal and textural analysis methods in quantification of EP tissue architecture.

  10. Structure and Physiological Actions of Ghrelin

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    Christine Delporte

    2013-01-01

    Full Text Available Ghrelin is a gastric peptide hormone, discovered as being the endogenous ligand of growth hormone secretagogue receptor. Ghrelin is a 28 amino acid peptide presenting a unique n-octanoylation modification on its serine in position 3, catalyzed by ghrelin O-acyl transferase. Ghrelin is mainly produced by a subset of stomach cells and also by the hypothalamus, the pituitary, and other tissues. Transcriptional, translational, and posttranslational processes generate ghrelin and ghrelin-related peptides. Homo- and heterodimers of growth hormone secretagogue receptor, and as yet unidentified receptors, are assumed to mediate the biological effects of acyl ghrelin and desacyl ghrelin, respectively. Ghrelin exerts wide physiological actions throughout the body, including growth hormone secretion, appetite and food intake, gastric secretion and gastrointestinal motility, glucose homeostasis, cardiovascular functions, anti-inflammatory functions, reproductive functions, and bone formation. This review focuses on presenting the current understanding of ghrelin and growth hormone secretagogue receptor biology, as well as the main physiological effects of ghrelin.

  11. Ghrelin counteracts salt-induced hypertension via promoting diuresis and renal nitric oxide production in Dahl rats.

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    Aoki, Hirotaka; Nakata, Masanori; Dezaki, Katsuya; Lu, Ming; Gantulga, Darambazar; Yamamoto, Keiji; Shimada, Kazuyuki; Kario, Kazuomi; Yada, Toshihiko

    2013-01-01

    Ghrelin is the endogenous ligand for the growth hormone-secretagogue receptor expressed in various tissues including the heart, blood vessels and kidney. This study sought to determine the effects of long-term treatment with ghrelin (10 nmol/kg, twice a day, intraperitoneally) on the hypertension induced by high salt (8.0% NaCl) diet in Dahl salt-sensitive hypertensive (DS) rats. Systolic blood pressure (SBP) was measured by a tail cuff method. During the treatment period for 3 weeks, high salt diet increased blood pressure compared to normal salt (0.3% NaCl) diet, and this hypertension was partly but significantly (P<0.01) attenuated by simultaneous treatment with ghrelin. Ghrelin significantly increased urine volume and tended to increase urine Na⁺ excretion. Furthermore, ghrelin increased urine nitric oxide (NO) excretion and tended to increase renal neuronal nitric oxide synthase (nNOS) mRNA expression. Ghrelin did not alter the plasma angiotensin II level and renin activity, nor urine catecholamine levels. Furthermore, ghrelin prevented the high salt-induced increases in heart thickness and plasma ANP mRNA expression. These results demonstrate that long-term ghrelin treatment counteracts salt-induced hypertension in DS rats primarily through diuretic action associated with increased renal NO production, thereby exerting cardio-protective effects.

  12. Changes in Ghrelin-Related Factors in Gastroesophageal Reflux Disease in Rats

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    Miwa Nahata

    2013-01-01

    Full Text Available To examine gastrointestinal hormone profiles and functional changes in gastroesophageal reflux disease (GERD, blood levels of the orexigenic hormone ghrelin were measured in rats with experimentally induced GERD. During the experiment, plasma acyl ghrelin levels in GERD rats were higher than those in sham-operated rats, although food intake was reduced in GERD rats. Although plasma levels of the appetite-suppressing hormone leptin were significantly decreased in GERD rats, no changes were observed in cholecystokinin levels. Repeated administration of rat ghrelin to GERD rats had no effect on the reduction in body weight or food intake. Therefore, these results suggest that aberrantly increased secretion of peripheral ghrelin and decreased ghrelin responsiveness may occur in GERD rats. Neuropeptide Y and agouti-related peptide mRNA expression in the hypothalamus of GERD rats was significantly increased, whereas proopiomelanocortin mRNA expression was significantly decreased compared to that in sham-operated rats. However, melanin-concentrating hormone (MCH and prepro-orexin mRNA expression in the hypothalamus of GERD rats was similar to that in sham-operated rats. These results suggest that although GERD rats have higher plasma ghrelin levels, ghrelin signaling in GERD rats may be suppressed due to reduced MCH and/or orexin synthesis in the hypothalamus.

  13. Ghrelin secretion stimulated by β1-adrenergic receptors in cultured ghrelinoma cells and in fasted mice

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    Zhao, Tong-Jin; Sakata, Ichiro; Liang, Guosheng; Richardson, James A.; Brown, Michael S.; Goldstein, Joseph L.; Zigman, Jeffrey M.

    2010-01-01

    Ghrelin, an octanoylated peptide hormone produced in the stomach, rises dramatically in mouse plasma during chronic severe calorie deprivation, an event that is essential to maintain life. The mechanism for this increase is not understood. Here, we study the control of ghrelin secretion in tissue culture cells derived from mice bearing ghrelinomas induced by a tissue-specific SV40 T-antigen transgene. We found that the ghrelin-secreting cells express high levels of mRNA encoding β1-adrenergic receptors. Addition of norepinephrine or epinephrine to the culture medium stimulated ghrelin secretion, and this effect was blocked by atenolol, a selective β1-adrenergic antagonist. When WT mice were treated with reserpine to deplete adrenergic neurotransmitters from sympathetic neurons, the fasting-induced increase in plasma ghrelin was blocked. Inhibition was also seen following atenolol administration. We conclude that ghrelin secretion during fasting is induced by adrenergic agents released by sympathetic neurons and acting directly on β1 receptors on the ghrelin-secreting cells of the stomach. PMID:20713709

  14. Ghrelin Inhibition Restores Glucose Homeostasis in Hepatocyte Nuclear Factor-1α (MODY3)-Deficient Mice.

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    Brial, François; Lussier, Carine R; Belleville, Karine; Sarret, Philippe; Boudreau, François

    2015-09-01

    Hepatocyte nuclear factor-1α (HNF1α) is a transcription factor expressed in tissues of endoderm origin. Mutations in HNF1A are associated with maturity-onset diabetes of the young 3 (MODY3). Mice deficient for Hnf1α are hyperglycemic, with their pancreatic β-cells being defective in glucose-sensing insulin secretion. The specific mechanisms involved in this defect are unclear. Gut hormones control glucose homeostasis. Our objective was to explore whether changes in these hormones play a role in glucose homeostasis in the absence of Hnf1α. An increase in ghrelin gene transcript and a decrease in glucose-dependent insulinotropic polypeptide (GIP) gene transcripts were observed in the gut of Hnf1α-null mice. These changes correlated with an increase of ghrelin and a decrease of GIP-labeled cells. Ghrelin serological levels were significantly induced in Hnf1α-null mice. Paradoxically, GIP levels were also induced in these mice. Treatment of Hnf1α-null mice with a ghrelin antagonist led to a recovery of the diabetic symptoms. We conclude that upregulation of ghrelin in the absence of Hnf1α impairs insulin secretion and can be reversed by pharmacological inhibition of ghrelin/GHS-R interaction. These observations open up on future strategies to counteract ghrelin action in a program that could become beneficial in controlling non-insulin-dependent diabetes.

  15. Underlying Mechanism of Aconitum Lizhong Acting on Experimental Hypothermia with Indigestion in Rats: Role of Ghrelin

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    Xin Zhao

    2012-01-01

    Full Text Available This study is aimed to investigate the Aconitum Lizhong pill (ALZ pharmacological actions on hypothermia with indigestion, especially the ghrelin roles. The littermate-matched rats were randomly divided into four groups. Control did sham operation or standard diet, Model carried out interscapular brown adipose (IBA removal with standard diet, Fat-diet did IBA removal with fat-diet, and ALZ did IBA removal and fat-diet with 4.536 g/kg/d ALZ. The potency of adaptive thermogenesis, ghrelin levels in plasma or gastric mucosa, thyroid hormones and metabolite in sera, expression of ghrelin mRNA, and protein in gastric mucous membrane were determined. ALZ relieved the hypothermia processes with indigestion, via inhibiting ghrelin expression and increasing ghrelin secretion; the dynamics from the therapy is supported with the energy changes as less body weight loss, less plasma lipid decrease, more plasma T3 or T4 increase with TSH decrease, and more compensation of thermogenic AUC decrease. Ghrelin played key roles in the actions of ALZ on the hypothermia with indigestion. The pharmacological mechanisms of ALZ involved the homeostasis of ghrelin expression and secretion.

  16. Ghrelin secretion stimulated by {beta}1-adrenergic receptors in cultured ghrelinoma cells and in fasted mice.

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    Zhao, Tong-Jin; Sakata, Ichiro; Li, Robert Lin; Liang, Guosheng; Richardson, James A; Brown, Michael S; Goldstein, Joseph L; Zigman, Jeffrey M

    2010-09-07

    Ghrelin, an octanoylated peptide hormone produced in the stomach, rises dramatically in mouse plasma during chronic severe calorie deprivation, an event that is essential to maintain life. The mechanism for this increase is not understood. Here, we study the control of ghrelin secretion in tissue culture cells derived from mice bearing ghrelinomas induced by a tissue-specific SV40 T-antigen transgene. We found that the ghrelin-secreting cells express high levels of mRNA encoding beta(1)-adrenergic receptors. Addition of norepinephrine or epinephrine to the culture medium stimulated ghrelin secretion, and this effect was blocked by atenolol, a selective beta(1)-adrenergic antagonist. When WT mice were treated with reserpine to deplete adrenergic neurotransmitters from sympathetic neurons, the fasting-induced increase in plasma ghrelin was blocked. Inhibition was also seen following atenolol administration. We conclude that ghrelin secretion during fasting is induced by adrenergic agents released by sympathetic neurons and acting directly on beta(1) receptors on the ghrelin-secreting cells of the stomach.

  17. Comparison of IL-6, IL-8 Concentrations in H. pylori- and non-H. pylori-associated Gastritis

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    Gontar Alamsyah Siregar

    2014-12-01

    Full Text Available BACKGROUND: Helicobacter pylori is a non-invasive microorganism causing intense gastric mucosal inflammatory and immune reaction. The gastric mucosal levels of the proinflammatory cytokines Interleukin 6 (IL-6 and IL-8 have been reported to be increased in H. pylori infection, but the serum levels in H. pylori infection is still controversial. The purpose of this study was to investigate the serum levels of IL-6 and IL-8 in H. pylori infection. METHODS: A cross sectional study was done on eighty consecutive gastritis patients admitted to endoscopy units at Adam Malik General Hospital and Permata Bunda Hospital, Medan, Indonesia from May-October 2014. Histopathology was performed for the diagnosis of gastritis. Rapid urease test for diagnosis of H. pylori infection. Serum samples were obtained to determine circulating IL-6 and IL-8. Univariate and bivariate analysis (independent t test were done. RESULTS: There were 41.25% patients infected with H. pylori. Circulatory IL-6 levels were significantly higher in H. pylori-infected patients compared to H. pylori negative, but there were no differences between serum levels of IL-8 in H. pylori positive and negative patients. CONCLUSIONS: The immune response to H. pylori promotes systemic inflammation, which was reflected in an increased level of serum IL-6. Serum levels of IL-8 were not significantly different between H. pylori positive and negative. KEYWORDS: Helicobacter pylori, gastritis, IL-6, IL-8, cytokine.

  18. Prevalence of Helicobacter pylori in benign gastric ulcers in a cohort of Sri Lankan patients.

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    Wijetunge, S; Kotakadeniya, R; Noordeen, F; Buharideen, S M; Samarasinghe, B; Dharmapala, A; Galketiya, K B

    2015-12-01

    Helicobacter pylori prevalence is decreasing globally and prevalence of non H. pylori gastric ulcers is increasing. The following study was conducted to assess the prevalence of H. pylori in benign gastric ulcers in a sample of Sri Lankan patients. This was a cross-sectional study of 59 dyspeptic patients with benign gastric ulcers. Multiple endoscopic gastric biopsies were obtained and histology, immunohistochemistry and polymerase chain reaction were performed for H. pylori detection. An immunochromatography assay was performed to detect blood anti H. pylori antibodies. Four (6.8%) were positive for H. pylori. Therefore, it is likely that most benign gastric ulcers are of non-H. pylori aetiology.

  19. Ghrelin modulates sympathetic nervous system activity and stress response in lean and overweight men.

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    Lambert, Elisabeth; Lambert, Gavin; Ika-Sari, Carolina; Dawood, Tye; Lee, Katie; Chopra, Reena; Straznicky, Nora; Eikelis, Nina; Drew, Sara; Tilbrook, Alan; Dixon, John; Esler, Murray; Schlaich, Markus P

    2011-07-01

    Ghrelin is a growth hormone-releasing peptide secreted by the stomach with potent effects on appetite. Experimental and clinical studies indicate that ghrelin also influences cardiovascular regulation and metabolic function and mediates behavioral responses to stress. We investigated the effects of ghrelin on blood pressure (BP), sympathetic nervous system activity, and mental stress responses in lean (n=13) and overweight or obese (n=13) individuals. Subjects received an intravenous infusion of human ghrelin (5 pmol/kg per minute for 1 hour) and saline in a randomized fashion. Ghrelin decreased systolic (-6 and -11 mm Hg) and diastolic BP (-8 mm Hg for both), increased muscle sympathetic nervous system activity (18±2 to 28±3 bursts per min, P<0.05 and from 21±2 to 32±3 bursts per min, P<0.001) in lean and overweight or obese subjects, respectively, without a significant change in heart rate, calf blood flow, or vascular resistance. Ghrelin induced a rise in plasma glucose concentration in lean individuals (P<0.05) and increased cortisol levels in both groups (P<0.05). Stress induced a significant change in mean BP (+22 and +27 mm Hg), heart rate (+36 and +29 bpm), and muscle sympathetic nervous system activity (+6.1±1.6 and +6.8±2.7 bursts per min) during saline infusion in lean and overweight or obese subjects, respectively. During ghrelin infusion, the changes in BP and muscle sympathetic nerve activity in response to stress were significantly reduced in both groups (P<0.05). In conclusion, ghrelin exerts unique effects in that it reduces BP and increases muscle sympathetic nervous system activity and blunts cardiovascular responses to mental stress. These responses may represent a combination of peripheral (baroreflex-mediated) and central effects of ghrelin.

  20. Helicobacter pylori-induced modulation of the promoter methylation of Wnt antagonist genes in gastric carcinogenesis.

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    Yang, Hyo-Joon; Kim, Sang Gyun; Lim, Joo Hyun; Choi, Ji Min; Kim, Woo Ho; Jung, Hyun Chae

    2017-06-22

    This study aimed to investigate the changes in the promoter methylation and gene expression of multiple Wnt antagonists between the chronic infection and eradication of Helicobacter pylori (H. pylori) in gastric carcinogenesis. The levels of methylation and corresponding mRNA expression of seven Wnt antagonist genes (SFRP1, -2, -5, DKK1, -2, -3, WIF1) were compared among the patients with H. pylori-positive gastric cancers (GCs), and H. pylori-positive and H. pylori-negative controls, by quantitative MethyLight assay and real-time reverse transcription (RT)-polymerase chain reaction (PCR), respectively. The changes of the methylation and expression levels of the genes were also compared between the H. pylori eradication and H. pylori-persistent groups 1 year after endoscopic resection of GCs. The methylation levels of SFRP and DKK family genes were significantly increased in the patients with H. pylori-positive GCs and followed by H. pylori-positive controls compared with H. pylori-negative controls (P pylori-negative controls, H. pylori-positive controls, and to H. pylori-positive GCs (P pylori eradication (P pylori-associated gastric carcinogenesis. The epigenetic field may not be reversed even after H. pylori eradication except by DKK3 methylation.

  1. CagA-positive Helicobacter pylori strain containing three EPIYA C phosphorylation sites produces increase of G cell and decrease of D cell in experimentally infected gerbils (Meriones unguiculatus).

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    Júnior, Moacir Ferreira; Batista, Sérgio de Assis; Barbuto, Rafael Calvão; Gomes, Adriana Dias; Queiroz, Dulciene Maria Magalhães; Araújo, Ivana Duval; Caliari, Marcelo Vidigal

    2016-09-01

    Human infection by Helicobacter pylori is associated with an increase in the number of gastrin-producing G cells and a concomitant decrease of somatostatin-producing D cells. However, to our knowledge, changes in G and D cell numbers in response to infection with H. pylori CagA-positive strains containing different number of EPIYA-C phosphorylation sites have not been analyzed to date. Therefore, the aim of this study was to perform a quantitative analysis of the number of G and D cells in Mongolian gerbils challenged with H. pylori strains with different numbers of EPIYA-C motifs. Mongolian gerbils were inoculated with isogenic H. pylori strains containing one to three phosphorylation sites. Mucosal fragments were evaluated by morphometry and immunohistochemistry using primary polyclonal rabbit anti-gastrin and anti-somatostatin antibodies. Positive cells were counted using an image analyzer. Forty-five days after infection, there was a decrease in the number of D cells and an increase in the G/D cell ratio in the group with three EPIYA-C. Six months after infection, there was a progressive and significant increase in the number of G cells and in the G/D cell ratio, with a concomitant decrease in the number of D cells, especially in the three EPIYA-C group. CagA-positive H. pylori strains containing a large number of EPIYA-C phosphorylation sites induce a decrease in D cell number and an increase in G cell number and G/D ratio, which were correlated with the number of inflammatory cells of the lamina propria. Copyright © 2016 Medical University of Bialystok. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  2. The gut hormone ghrelin partially reverses energy substrate metabolic alterations in the failing heart.

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    Mitacchione, Gianfranco; Powers, Jeffrey C; Grifoni, Gino; Woitek, Felix; Lam, Amy; Ly, Lien; Settanni, Fabio; Makarewich, Catherine A; McCormick, Ryan; Trovato, Letizia; Houser, Steven R; Granata, Riccarda; Recchia, Fabio A

    2014-07-01

    The gut-derived hormone ghrelin, especially its acylated form, plays a major role in the regulation of systemic metabolism and exerts also relevant cardioprotective effects; hence, it has been proposed for the treatment of heart failure (HF). We tested the hypothesis that ghrelin can directly modulate cardiac energy substrate metabolism. We used chronically instrumented dogs, 8 with pacing-induced HF and 6 normal controls. Human des-acyl ghrelin [1.2 nmol/kg per hour] was infused intravenously for 15 minutes, followed by washout (rebaseline) and infusion of acyl ghrelin at the same dose. (3)H-oleate and (14)C-glucose were coinfused and arterial and coronary sinus blood sampled to measure cardiac free fatty acid and glucose oxidation and lactate uptake. As expected, cardiac substrate metabolism was profoundly altered in HF because baseline oxidation levels of free fatty acids and glucose were, respectively, >70% lower and >160% higher compared with control. Neither des-acyl ghrelin nor acyl ghrelin significantly affected function and metabolism in normal hearts. However, in HF, des-acyl and acyl ghrelin enhanced myocardial oxygen consumption by 10.2±3.5% and 9.9±3.7%, respectively (P<0.05), and cardiac mechanical efficiency was not significantly altered. This was associated, respectively, with a 41.3±6.7% and 32.5±10.9% increase in free fatty acid oxidation and a 31.3±9.2% and 41.4±8.9% decrease in glucose oxidation (all P<0.05). Acute increases in des-acyl or acyl ghrelin do not interfere with cardiac metabolism in normal dogs, whereas they enhance free fatty acid oxidation and reduce glucose oxidation in HF dogs, thus partially correcting metabolic alterations in HF. This novel mechanism might contribute to the cardioprotective effects of ghrelin in HF. © 2014 American Heart Association, Inc.

  3. Histomorphometric features of ventral prostate in different aged rats after central ghrelin treatment.

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    Plecas-Solarovic, Bosiljka A; Nesic, Dejan M; Stevanovic, Darko M; Obradovic, Aleksandar Lj; Djelic, Marina N; Milosevic, Verica Lj; Starcevic, Vesna P

    2012-06-01

    Ghrelin, the endogenous ligand of growth hormone secretagogue receptor type 1a (GHS-R1a), has emerged as pleiotropic modulator of diverse biological functions, including energy homeostasis and recently, reproduction. The influence of intracerebroventricularly (ICV) administered ghrelin (1 μg/day/rat for 5 days) to rats of different ages, i.e, peripubertal (38 days), adult (60 days) and middle-aged (180 days) on the ventral prostate size and morphology, serum testosterone levels and testis weight was examined. Ghrelin treatment significantly increased (p prostate weight in peripubertal and middle-aged rats, by 27% and 37% respectively, due to enhancement of epithelial and/or luminal compartment of the gland. In adult rats, both absolute and relative volumes of the acinar lumen were significantly decreased (p prostate weigh was unchanged. Irrespective of animal age, ghrelin did not affect serum testosterone levels. These are the first results of ghrelin treatment effects on healthy prostate appearance, which allow us to conclude that the rat ventral prostate response to ghrelin depends on the developmental stage of animals. Our results merit further investigations and may have clinical implications, especially in the light of data on possible role of ghrelin in prostate hypertrophy and adenomas.

  4. Photoperiod influences the central effects of ghrelin on food intake, GH and LH secretion in sheep.

    Science.gov (United States)

    Harrison, Joanne L; Miller, David W; Findlay, Patricia A; Adam, Clare L

    2008-01-01

    Ghrelin is a circulating peptide, primarily secreted by the gut, that has reported actions within the hypothalamo-pituitary axis to stimulate food intake, inhibit GnRH/LH secretion and stimulate GH secretion in monogastric species. Here, we examine responses to centrally administered ghrelin in a seasonal ruminant. Estradiol-implanted castrated male sheep with indwelling intracerebroventricular (i.c.v.) cannulae were kept with unrestricted food for 16 weeks in long day photoperiod (LD, 16 h light/day) then 16 weeks in short days (SD, 8 h light/day). In week 16 of each photoperiod they were given a control (saline) i.c.v. injection on day 1 and ghrelin i.c.v. injection on day 2. Mean circulating endogenous plasma ghrelin concentrations showed no diurnal pattern and were similar between the photoperiods. Central ghrelin injection increased voluntary food intake 2-fold in the first hour after administration in LD but not in SD, decreased LH pulse frequency and amplitude in SD but not in LD, and stimulated GH release in both photoperiods, although there was a 1.5-fold larger response in LD. Therefore, central injection of ghrelin to sheep acutely stimulated food intake in LD, suppressed reproductive neuroendocrine output in SD, and stimulated GH secretion irrespective of photoperiod, although more pronounced in LD. These data indicate that photoperiod can influence hypothalamic appetite and reproductive neuroendocrine responses to ghrelin in seasonal species.

  5. Ghrelin and the growth hormone secretagogue receptor in growth and development.

    Science.gov (United States)

    Chanoine, J-P; De Waele, K; Walia, P

    2009-04-01

    The pancreas is a major source of ghrelin in the perinatal period, whereas gastric production progressively increases after birth. Loss of function of the genes for ghrelin or for the constitutively activated growth hormone secretagogue receptor (GHSR) does not affect birth weight and early postnatal growth. However, ghrl(-/-) or ghsr(-/-) mice fed a high fat diet starting soon after weaning are resistant to diet-induced obesity, suggesting that ghrelin affects the maturation of the metabolic axes involved in energy balance. In addition, animal and human studies suggest that GHSR plays a physiological role in linear growth. In mice, absence of the GHSR gene is associated with lower insulin-like growth factor 1 concentrations and lower body mass in adult animals, independently of food intake. In humans, a mutation of the GHSR gene that impairs the constitutive activity of the receptor was found in two families with short stature. Administration of acylated ghrelin to rat pups directly does not affect weight gain. In contrast, administration of ghrelin to pregnant or lactating rats results in greater fetal weight and postnatal weight gain, respectively, suggesting that maternal ghrelin may stimulate perinatal growth. These data point toward a physiological role for ghrelin and GHSR in growth and/or in the maturation of hormonal systems involved in the regulation of energy balance.

  6. Exogenous Ghrelin Accelerates the Healing of Acetic Acid-Induced Colitis in Rats

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    Aleksandra Matuszyk

    2016-09-01

    Full Text Available Previous studies have shown that ghrelin reduces colonic inflammation induced by trinitrobenzene sulfonic acid and dextran sodium sulfate. In the present study we determined the effect of treatment with ghrelin on the course of acetic acid-induced colitis in rats. Rectal administration of 3% acetic acid solution led to induction of colitis in all animals. Damage of the colonic wall was accompanied by an increase in mucosal concentration of pro-inflammatory interleukin-1β (IL-1β and tumor necrosis factor-α (TNF-α, as well mucosal activity of myeloperoxidase. Moreover, induction of colitis led to a reduction in colonic blood flow and DNA synthesis. Administration of ghrelin after induction of colitis led to faster regeneration of the colonic wall and reduction in colonic levels of IL-1β, TNF-α, and myeloperoxidase. In addition, treatment with ghrelin improved mucosal DNA synthesis and blood flow. Our study disclosed that ghrelin exhibits a strong anti-inflammatory and healing effect in acetic acid-induced colitis. Our current observation in association with previous findings that ghrelin exhibits curative effect in trinitrobenzene sulfonic acid- and dextran sodium sulfate-induced colitis suggest that therapeutic effect of ghrelin in the colon is universal and independent of the primary cause of colitis.

  7. Functionally biased signalling properties of 7TM receptors - opportunities for drug development for the ghrelin receptor

    DEFF Research Database (Denmark)

    Sivertsen, B; Holliday, N; Madsen, A N

    2013-01-01

    UNLABELLED: The ghrelin receptor is a 7 transmembrane (7TM) receptor involved in a variety of physiological functions including growth hormone secretion, increased food intake and fat accumulation as well as modulation of reward and cognitive functions. Because of its important role in metabolism...... and energy expenditure, the ghrelin receptor has become an important therapeutic target for drug design and the development of anti-obesity compounds. However, none of the compounds developed so far have been approved for commercial use. Interestingly, the ghrelin receptor is able to signal through several...

  8. Helicobacter pylori: epidemiology and routes of transmission.

    Science.gov (United States)

    Brown, L M

    2000-01-01

    H. pylori is a common bacterium, and approximately 50 percent of the world's population has been estimated to be infected (198). Humans are the principal reservoir. The prevalence of H. pylori infection varies widely by geographic area, age, race, ethnicity, and SES. Rates appear to be higher in developing than in developed countries, with most of the infections occurring during childhood, and they seem to be decreasing with improvements in hygiene practices. H. pylori causes chronic gastritis and has been associated with several serious diseases of the gastrointestinal tract, including duodenal ulcer and gastric cancer. Since its "discovery" in 1982 by Warren and Marshall (1), H. pylori has been the topic of extensive research. A number of studies have used questionnaire components to investigate factors possibly related to the etiology of H. pylori infection. The majority of recent studies have not found tobacco use or alcohol consumption to be risk factors for H. pylori infection. Adequate nutritional status, especially frequent consumption of fruits and vegetables and of vitamin C, appears to protect against infection with H. pylori. In contrast, food prepared under less than ideal conditions or exposed to contaminated water or soil may increase the risk. Overall, inadequate sanitation practices, low social class, and crowded or high-density living conditions seem to be related to a higher prevalence of H. pylori infection. This finding suggests that poor hygiene and crowded conditions may facilitate transmission of infection among family members and is consistent with data on intrafamilial and institutional clustering of H. pylori infection. Understanding the route of H. pylori transmission is important if public health measures to prevent its spread are to be implemented. Iatrogenic transmission of H. pylori following endoscopy is the only proven mode. For the general population, the most likely mode of transmission is from person to person, by either the

  9. Effects of ghrelin on psychopathology, sleep and secretion of cortisol and growth hormone in patients with major depression.

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    Kluge, Michael; Schüssler, Petra; Dresler, Martin; Schmidt, Doreen; Yassouridis, Alexander; Uhr, Manfred; Steiger, Axel

    2011-03-01

    Ghrelin showed antidepressant-like effects in mice. Furthermore, ghrelin influences sleep and the activity of hypothalamic-pituitary-adrenal (HPA) and somatotropic axis in healthy humans as indicated by increased cortisol and growth hormone (GH) plasma levels. Both sleep and the activity of these endocrine axes are disturbed in depression. We therefore studied the impact of ghrelin on psychopathology, sleep and secretion of cortisol and GH in patients with major depression. Depressive symptoms as assessed by a validated self rating scale ('Befindlichkeits-Skala', [mental state scale]), secretion profiles of cortisol and GH and sleep-EEGs were determined in 14 unmedicated patients with major depression (7 women) twice, receiving 50 μg ghrelin or placebo at 22:00, 23:00, 00:00, and 01:00 hours. Overall, depressive symptoms did not change significantly after ghrelin administration (placebo: 37 ± 8; ghrelin: 33 ± 10, p = 0.178). However, there was an improvement at trend level in men (placebo: 36 ± 9 to ghrelin: 30 ± 9, p = 0.093) but not in women. In men, ghrelin was associated with less time awake (placebo: 149.0 ± 11.1; ghrelin: 88.0 ± 12.2 min, p = 0.029) and more non-REM sleep (placebo: 263.2 ± 24.1; ghrelin: 304.9 ± 14.1 min, p = 0.027), in women with less REM sleep (placebo: 108.6 ± 15.7; ghrelin: 74.1 ± 13.8 min, p = 0.031) and longer REM latency (placebo: 49.9 ± 6.5; ghrelin: 85.6 ± 14.1 min, p = 0.019). In both sexes, ghrelin caused strong transient increases of GH and cortisol. In conclusion, our study may provide some initial indication that ghrelin can exert antidepressant effects in patients with major depression. Ghrelin strongly affected sleep and secretion of GH and cortisol in a partly different way as previously reported in healthy subjects.

  10. [Peptic Ulcer Disease Associated with Helicobacter pylori Infection].

    Science.gov (United States)

    Yeo, Se-Hwan; Yang, Chang-Hun

    2016-06-25

    Although the global prevalence of peptic ulcer disease (PUD) is decreasing, PUD is still one of the most common upper gastrointestinal diseases in the world due to Helicobacter pylori infection and increased use of non-steroidal anti-inflammatory drugs. In Korea, the prevalence of H. pylori infection is also declining, but it is still the major cause of PUD. The outcomes of H. pylori infection are caused by imbalances between bacterial virulence factors, host factors, and environmental influences. In this review, we describe the prevalence trends of H. pylori infection in Korea, the mechanism of H. pylori infection-related PUD, and treatment strategies.

  11. Acylated and Desacylated Ghrelin, Preptin, Leptin, and Nesfatin-1 Peptide Changes Related to the Body Mass Index

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    Yusuf Ozkan

    2013-01-01

    Full Text Available This study examines the levels of acylated and desacylated ghrelin, preptin, leptin, and nesfatin-1 peptide changes related to the body mass index (BMI. The subjects were allocated to 5 groups depending on their BMIs as follows: Group I (BMI 40 kg/m2. Serum acylated and desacylated ghrelin, preptin, and leptin levels were measured by the enzyme-linked immunosorbent assay (ELISA and nesfatin-1 was measured by the enzyme immunoassay (EIA. Desacylated ghrelin levels showed a gradual and statistically significant drop from Group I to Group V, while preptin and leptin levels exhibited a gradual and significant increase from Group I to Group IV. Serum nesfatin-1 levels gradually, but not significantly, increased from Group I to Group III and showed a significant decrease in Groups IV and V. In conclusion, leptin, preptin, and acylated ghrelin (AG levels increased with higher BMI, whereas desacylated ghrelin (DAG decreased and nesfatin-1 showed no clear relationship to BMI.

  12. The GOAT-ghrelin system is not essential for hypoglycemia prevention during prolonged calorie restriction.

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    Chun-Xia Yi

    Full Text Available OBJECTIVE: Ghrelin acylation by ghrelin O-acyltransferase (GOAT has recently been reported to be essential for the prevention of hypoglycemia during prolonged negative energy balance. Using a unique set of four different genetic loss-of-function models for the GOAT/ghrelin/growth hormone secretagogue receptor (GHSR system, we thoroughly tested the hypothesis that lack-of-ghrelin activation or signaling would lead to hypoglycemia during caloric deprivation. METHODOLOGY: Male and female knockout (KO mice for GOAT, ghrelin, GHSR, or both ghrelin and GHSR (dKO were subjected to prolonged calorie restriction (40% of ad libitum chow intake. Body weight, fat mass, and glucose levels were recorded daily and compared to wildtype (WT controls. Forty-eight hour blood glucose profiles were generated for each individual mouse when 2% or less body fat mass was reached. Blood samples were obtained for analysis of circulating levels of acyl- and desacyl-ghrelin, IGF-1, and insulin. PRINCIPAL FINDINGS: Chronic calorie restriction progressively decreased body weight and body fat mass in all mice regardless of genotype. When fat mass was depleted to 2% or less of body weight for 2 consecutive days, random hypoglycemic events occurred in some mice across all genotypes. There was no increase in the incidence of hypoglycemia in any of the four loss-of-function models for ghrelin signaling including GOAT KO mice. Furthermore, no differences in insulin or IGF-1 levels were observed between genotypes. CONCLUSION: The endogenous GOAT-ghrelin-GHSR system is not essential for the maintenance of euglycemia during prolonged calorie restriction.

  13. EFFECTS OF ENDURANCE RUNNING AND DIETARY FAT ON CIRCULATING GHRELIN AND PEPTIDE YY

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    Enette D. Larson-Meyer

    2009-12-01

    Full Text Available Ghrelin and peptide YY (PYY are newly recognized gut peptides involved in appetite regulation. Plasma ghrelin concentrations are elevated in fasting and suppressed following a meal, while PYY concentrations are suppressed in fasting and elevated postprandially. We determine whether ghrelin and PYY are altered by a low-fat, high-carbohydrate (10% fat, 75% carbohydrate or moderate-fat, moderate-carbohydrate (35% fat, 50% carbohydrate diet and; whether these peptides are affected by intense endurance running (which is likely to temporarily suppress appetite. Twenty-one endurance-trained runners followed a controlled diet (25% fat and training regimen for 3 days before consuming the low-fat or isoenergetic moderate-fat diet for another 3 days in random cross-over fashion. On day 7 runners underwent glycogen restoration and then completed a 90-minute pre-loaded 10-km time trial on day 8, following a control breakfast. Blood samples were obtained on days 4 and 7 (fasting, and day 8 (non-fasting before and after exercise for analysis of ghrelin, PYY, insulin and growth hormone (GH. Insulin, GH, Ghrelin and PYY changed significantly over time (p < 0.0001 but were not influenced by diet. Ghrelin was elevated during fasting (days 4 and 7, while insulin and PYY were suppressed. Following the pre-exercise meal, ghrelin was suppressed ~17% and insulin and PYY were elevated ~157 and ~40%, respectively, relative to fasting (day 7. Following exercise, PYY, ghrelin, and GH were significantly (p < 0.0001 increased by ~11, ~16 and ~813%, respectively. The noted disruption in the typical inverse relationship between ghrelin and PYY following exercise suggests that interaction of these peptides may be at least partially responsible for post-exercise appetite suppression. These peptides do not appear to be influenced by dietary fat intake

  14. Activation of somatostatin 2 receptors in the brain and the periphery induces opposite changes in circulating ghrelin levels: functional implications

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    Andreas eStengel

    2013-01-01

    Full Text Available Somatostatin is an important modulator of neurotransmission in the central nervous system and acts as a potent inhibitor of hormone and exocrine secretion and regulator of cell proliferation in the periphery. These pleiotropic actions occur through interaction with five G-protein coupled somatostatin receptor subtypes (sst1-5 that are widely expressed in the brain and peripheral organs. The characterization of somatostatin’s effects can be investigated by pharmacological or genetic approaches using newly developed selective sst agonists and antagonists and mice lacking specific sst subtypes. Recent evidence points towards a divergent action of somatostatin in the brain and in the periphery to regulate circulating levels of ghrelin, an orexigenic hormone produced by the endocrine X/A-like cells in the gastric mucosa. Somatostatin interacts with the sst2 in the brain to induce an increase in basal ghrelin plasma levels and counteracts the visceral stress-related decrease in circulating ghrelin in rats. By contrast, stimulation of peripheral somatostatin-sst2 signaling results in the inhibition of basal ghrelin release and mediates the postoperative decrease in circulating ghrelin in rats. The peripheral sst2-mediated reduction of plasma ghrelin is likely to involve a paracrine action of D-cell derived somatostatin acting on sst2 bearing X/A-like ghrelin cells in the gastric mucosa. The other member of the somatostatin family, named cortistatin, in addition to binding to sst1-5 also directly interacts with the ghrelin receptor and therefore may simultaneously modulate ghrelin release and actions at target sites bearing ghrelin receptors representing a link between the ghrelin and somatostatin systems.

  15. Appetite regulation is independent of the changes in ghrelin levels in pregnant rats fed low-protein diet.

    Science.gov (United States)

    Gao, Haijun; Tanchico, Daren T; Yallampalli, Uma; Balakrishnan, Meena P; Yallampalli, Chandra

    2015-04-01

    Gestational protein restriction causes hypertension in the adult offspring. Very little is known about the food intake regulation and ghrelin signaling in pregnant dams fed a low-protein (LP) diet. We hypothesized that diet intake and ghrelin signaling are altered in pregnant rats fed the low-protein diet. Sprague-Dawley rats were fed a control (CT) or LP diet from Day 3 of pregnancy. Diet intake and body weight were monitored daily. Expression of ghrelin production-related genes in the stomach and appetite-related genes in the hypothalamus was analyzed by real-time PCR. Plasma levels of total and active ghrelin, growth hormone and leptin were measured by ELISA. Main results include: (1) Daily diet intake was greater in the LP group than in the CT group in early pregnancy, but substantially lower in late pregnancy; (2) Daily gain in body weight was substantially lower in the LP group in late pregnancy; (3) Expression of ghrelin production-related genes in the stomach and plasma total ghrelin levels were increased in LP group in late pregnancy; (4) Plasma active ghrelin levels were elevated in the LP group at mid-late pregnancy, but growth hormone and leptin levels were uncorrelated with active ghrelin in late pregnancy; and (5) Hypothalamic expression of ghrelin-stimulated genes in LP rats was unassociated with the changes in both plasma ghrelin levels and the diet intake. Taken together, the appetite in LP rats is greater in early pregnancy but reduced at late pregnancy, possibly due to ghrelin insensitivity in appetite regulation. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  16. Neonatal events, such as androgenization and postnatal overfeeding, modify the response to ghrelin.

    Science.gov (United States)

    Novelle, Marta G; Vázquez, María J; Martinello, Kátia D; Sanchez-Garrido, Miguel A; Tena-Sempere, Manuel; Diéguez, Carlos

    2014-05-06

    It is currently accepted that ambient, non-genetic factors influence perinatal development and evoke structural and functional changes that may persist throughout life. Overfeeding and androgenization after birth are two of these key factors that could result in "metabolic imprinting" of neuronal circuits early in life and, thereby, increase the body weight homeostatic "set point", stimulate appetite, and result in obesity. Our aim was to determine the influence of these obesogenic factors on the response to ghrelin. We observed the expected orexigenic effect of ghrelin regardless of the nutritional or hormonal manipulations to which the animals were subjected to at early postnatal development and this effect remained intact at later stages of development. In fact, ghrelin responses increased significantly when the animals were subjected to one of the two manipulations, but not when both were combined. An increased response to ghrelin could explain the obese phenotype displayed by individuals with modified perinatal environment.

  17. Plasma ghrelin concentrations, food intake, and anorexia in liver failure.

    Science.gov (United States)

    Marchesini, Giulio; Bianchi, Giampaolo; Lucidi, Paola; Villanova, Nicola; Zoli, Marco; De Feo, Pierpaolo

    2004-05-01

    Ghrelin is related to feeding behavior and nutrition in several physiological and pathological conditions. We tested the hypothesis that the anorexia and the decreased food intake of advanced liver failure might be associated with hyperghrelinemia. Fasting ghrelin was measured in 43 cirrhotic patients, food intake was self-assessed using the Corli score and a 3-d dietary record (n = 25), and anorexia/hunger was tested by a Likert scale. Fifty healthy subjects, matched for age and body mass index, served as controls. Ghrelin levels were not systematically increased in cirrhosis (414 +/- 164 vs. 398 +/- 142 pmol/liter in controls) but increased with decreasing Corli score (P = 0.014) and along the scale of anorexia/hunger (P = 0.0001), which were both related to the 3-d dietary record (P = 0.009 and P 500 pmol/liter) was significantly associated with a low calorie intake [odds ratio (OR), 3.03 for any 100-calorie reduced intake; P = 0.015], a reduced Corli score (OR, 3.09; P = 0.031), and the anorexia score (OR, 3.37; P = 0.009), after adjustment for body mass index. The study confirms the previously observed relationship of fasting ghrelin with food intake in disease-associated malnutrition. In the presence of anorexia, hyperghrelinemia might indicate a compensatory mechanism trying to stimulate food intake, which is nonetheless ineffective in the physiological range.

  18. Role of endogenous cortistatin in the regulation of ghrelin system expression at pancreatic level under normal and obese conditions.

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    Belén Chanclón

    Full Text Available Ghrelin-system components [native ghrelin, In1-ghrelin, Ghrelin-O-acyltransferase enzyme (GOAT and receptors (GHS-Rs] are expressed in a wide variety of tissues, including the pancreas, where they exert different biological actions including regulation of neuroendocrine secretions, food intake and pancreatic function. The expression of ghrelin system is regulated by metabolic conditions (fasting/obesity and is associated with the progression of obesity and insulin resistance. Cortistatin (CORT, a neuropeptide able to activate GHS-R, has emerged as an additional link in gut-brain interplay. Indeed, we recently reported that male CORT deficient mice (cort-/- are insulin-resistant and present a clear dysregulation in the stomach ghrelin-system. The present work was focused at analyzing the expression pattern of ghrelin-system components at pancreas level in cort-/- mice and their control littermates (cort +/+ under low- or high-fat diet. Our data reveal that all the ghrelin-system components are expressed at the mouse pancreatic level, where, interestingly, In1-ghrelin was expressed at higher levels than native-ghrelin. Thus, GOAT mRNA levels were significantly lower in cort-/- mice compared with controls while native ghrelin, In1-ghrelin and GHS-R transcript levels remained unaltered under normal metabolic conditions. Moreover, under obese condition, a significant increase in pancreatic expression of native-ghrelin, In1-ghrelin and GHS-R was observed in obese cort+/+ but not in cort-/- mice. Interestingly, insulin expression and release was elevated in obese cort+/+, while these changes were not observed in obese cort-/- mice. Altogether, our results indicate that the ghrelin-system expression is clearly regulated in the pancreas of cort+/+ and cort -/- under normal and/or obesity conditions suggesting that this system may play relevant roles in the endocrine pancreas. Most importantly, our data demonstrate, for the first time, that endogenous

  19. Helicobacter pylori: From Infection to Cure

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    ABR Thomson

    1996-01-01

    Full Text Available Over 380 abstracts, presentations and posters of recent advances were highlighted at the European and International Helicobacter pylori meeting held July 7 to 9, 1995 in Edinburgh, Scotland. New advances abound, with major interest focusing on the simple, safe, inexpensive new `gold standard’ for H pylori eradication therapy: a single week of tid omeprazole 20 mg, metronidazole 400 mg and clarithromycin 250 mg, or omeprazole 20 mg, amoxicillin 1000 mg and clarithromycin 500 mg. To avoid false negative results, two biopsies must be taken from the antrum and two from the gastric body at least four weeks after completion of eradication therapy, and ideally should be supplemented with at least one further H pylori test such as a biopsy for urease activity or culture, or a urea breath test. While most patients with a gastric or duodenal ulcer (DU who do not consume nonsteroidal anti-inflammatory drugs are infected with H pylori, the association is much less apparent in those with a DU who present with an upper gastrointestinal hemorrhage. H pylori eradication for nonulcer dyspepsia is not widely recommended, and the patient with a DU given effective H pylori eradication who presents with dyspepsia likely has erosive esophagitis rather than recurrent DU or H pylori. Gastroenterologists are at increased risk of H pylori infection, particularly older gastroenterologists who are very busy endoscopists.

  20. Molecular mimicry in Helicobacter pylori infections

    Science.gov (United States)

    Chmiela, Magdalena; Gonciarz, Weronika

    2017-01-01

    Gram-negative bacteria Helicobacter pylori (H. pylori) colonize gastric mucosa in humans and increase the risk of serious diseases such as gastric and duodenal ulcers, stomach cancers and mucosa associated lymphoid tissue lymphoma. The role of H. pylori infection in the pathogenesis of several extragastric diseases has been suggested including immune thrombocytopenic purpura, iron deficiency anemia, vitamin D deficiency, cardiovascular diseases, diabetes mellitus and dermatological disorders. Also neurological diseases and even lung cancer have attracted researchers concern. The relation between H. pylori infection and a growth retardation in children has also been suggested. Many mechanisms of molecular mimicry between H. pylori and the host have been proposed as a pathogen strategy to manipulate the immune system of the host in order to remain unrecognized and avoid eradication. A lot of effort has been put into the demonstration of homologous sequences between H. pylori and host compounds. However, knowledge about how often autoantibodies or autoreactive T lymphocytes induced during H. pylori infections cause pathological disorders is insufficient. This review provides data on H. pylori antigenic mimicry and possible deleterious effects due to the induction of immune response to the components common to these bacteria and the host. PMID:28652651

  1. Molecular mimicry in Helicobacter pylori infections.

    Science.gov (United States)

    Chmiela, Magdalena; Gonciarz, Weronika

    2017-06-14

    Gram-negative bacteria Helicobacter pylori (H. pylori) colonize gastric mucosa in humans and increase the risk of serious diseases such as gastric and duodenal ulcers, stomach cancers and mucosa associated lymphoid tissue lymphoma. The role of H. pylori infection in the pathogenesis of several extragastric diseases has been suggested including immune thrombocytopenic purpura, iron deficiency anemia, vitamin D deficiency, cardiovascular diseases, diabetes mellitus and dermatological disorders. Also neurological diseases and even lung cancer have attracted researchers concern. The relation between H. pylori infection and a growth retardation in children has also been suggested. Many mechanisms of molecular mimicry between H. pylori and the host have been proposed as a pathogen strategy to manipulate the immune system of the host in order to remain unrecognized and avoid eradication. A lot of effort has been put into the demonstration of homologous sequences between H. pylori and host compounds. However, knowledge about how often autoantibodies or autoreactive T lymphocytes induced during H. pylori infections cause pathological disorders is insufficient. This review provides data on H. pylori antigenic mimicry and possible deleterious effects due to the induction of immune response to the components common to these bacteria and the host.

  2. Gastric bicarbonate secretion and release of prostaglandin E2 are increased in duodenal ulcer patients but not in Helicobacter pylori-positive healthy subjects

    DEFF Research Database (Denmark)

    Mertz-Nielsen, A; Hillingsø, Jens; Frøkiaer, H;

    1996-01-01

    was present also in the stomach of DU patients. METHODS: Simultaneous determinations of gastric and duodenal bicarbonate secretion and luminal release of PGE2 were performed in 16 healthy volunteers (5 Helicobacter pylori-positive) and 8 inactive DU patients (all H. pylori-positive). RESULTS: In healthy...... volunteers the rates of gastroduodenal bicarbonate secretion and the release of PGE2 were not influenced by H. pylori status. In inactive DU patients the rates of basal (704 +/- 84 versus 356 +/- 40 mumol/h; mean +/- SEM) and vagally stimulated (modified sham feeding) (1724 +/- 376 versus 592 +/- 52 mumol...... for the abnormally high gastric secretion of bicarbonate in inactive DU patients. The defective duodenal secretion of bicarbonate observed in these patients may be a consequence of previous ulceration rather than the mere presence of H. pylori infection....

  3. Gastric bicarbonate secretion and release of prostaglandin E2 are increased in duodenal ulcer patients, but not in Helicobacter pylori positive healthy subjects

    DEFF Research Database (Denmark)

    A, Mertz-Nielsen; Hillingsø, Jens; Frøkiær, Hanne;

    1996-01-01

    was present also in the stomach of DU patients. Methods: Simultaneous determinations of gastric and duodenal bicarbonate secretion and luminal release of PGE(2) were performed in 16 healthy volunteers (5 Helicobacter pylori-positive) and 8 inactive DU patients (all H. pylori-positivr). Results: In healthy...... volunteers the rates of gastroduodenal bicarbonate secretion and the release of PGE(2), were not influenced by H. pylori status. In inactive DU patients the rates of basal (704 +/- 84 versus 356 +/- 40 mu mol/h: mean +/- SEM) and vagally stimulated (modified sham feeding) (1724 +/- 376 versus 592 +/- 52 mu...... be responsible for the abnormally high gastric secretion of bicarbonate in inactive DU patients. Th; defective duodenal secretion of bicarbonate observed in these patients may be a consequence of previous ulceration rather than the mere presence of H. pylori infection....

  4. Regulation of RKIP function by Helicobacter pylori in gastric cancer.

    Directory of Open Access Journals (Sweden)

    Erika L Moen

    Full Text Available Helicobacter pylori (H. pylori is a gram-negative, spiral-shaped bacterium that infects more than half of the world's population and is a major cause of gastric adenocarcinoma. The mechanisms that link H. pylori infection to gastric carcinogenesis are not well understood. In the present study, we report that the Raf-kinase inhibitor protein (RKIP has a role in the induction of apoptosis by H. pylori in gastric epithelial cells. Western blot and luciferase transcription reporter assays demonstrate that the pathogenicity island of H. pylori rapidly phosphorylates RKIP, which then localizes to the nucleus where it activates its own transcription and induces apoptosis. Forced overexpression of RKIP enhances apoptosis in H. pylori-infected cells, whereas RKIP RNA inhibition suppresses the induction of apoptosis by H. pylori infection. While inducing the phosphorylation of RKIP, H. pylori simultaneously targets non-phosphorylated RKIP for proteasome-mediated degradation. The increase in RKIP transcription and phosphorylation is abrogated by mutating RKIP serine 153 to valine, demonstrating that regulation of RKIP activity by H. pylori is dependent upon RKIP's S153 residue. In addition, H. pylori infection increases the expression of Snail, a transcriptional repressor of RKIP. Our results suggest that H. pylori utilizes a tumor suppressor protein, RKIP, to promote apoptosis in gastric cancer cells.

  5. Triterpenes suppress octanoylated ghrelin production in ghrelin-expressing human gastric carcinoma cells.

    Science.gov (United States)

    Nakajima, Kensuke; Oiso, Shigeru; Uto, Takuhiro; Morinaga, Osamu; Shoyama, Yukihiro; Kariyazono, Hiroko

    2016-01-01

    Ghrelin is an appetite-stimulating peptide hormone with an octanoyl modification at serine 3 that is essential for its orexigenic effect. Ghrelin O-acyltransferase (GOAT) is the enzyme that catalyzes ghrelin acylation using fatty acyl-coenzyme A as a substrate. We previously developed an assay system based on the AGS-GHRL8 cell line that produces octanoylated ghrelin in the presence of octanoic acid, and demonstrated that some fatty acids suppressed octanoylated ghrelin production. Recent studies have reported that triterpenes have anti-obesity effect. Since such triterpenes, like fatty acids, have a carboxyl group, we speculated that they can suppress octanoylated ghrelin production. To test this hypothesis, we investigated the effect of triterpenes on octanoylated ghrelin production. Asiatic acid, corosolic acid, glycyrrhetinic acid, oleanolic acid and ursolic acid suppressed octanoylated ghrelin levels in AGS-GHRL8 cells without decreasing transcript expression of GOAT or furin, a protease required for ghrelin maturation. β-amyrin had no effect on octanoylated ghrelin level, which was only slightly inhibited by uvaol; the fact that both these triterpenes lack a carboxyl group indicates that this group is important for suppressing octanoylated ghrelin production. These results suggest that triterpenes may have the potential as obesity-preventing agents with suppressive effect on octanoylated ghrelin production.

  6. Mechanism of Cytosolic Phospholipase A(2) Activation in Ghrelin Protection of Salivary Gland Acinar Cells against Ethanol Cytotoxicity.

    Science.gov (United States)

    Slomiany, Bronislaw L; Slomiany, Amalia

    2010-01-01

    Ghrelin, a peptide hormone, newly identified in oral mucosal tissues, has emerged recently as an important mediator of the processes of mucosal defense. Here, we report on the mechanism of ghrelin protection against ethanol cytotoxicity in rat sublingual salivary gland cells. The protective effect of ghrelin was associated with the increase in NO and PGE2, and upregulation in cytosolic phospholipase A(2) (cPLA(2)) activity and arachidonic acid (AA) release. The loss in countering effect of ghrelin occurred with cNOS inhibitor, L-NAME, as well as indomethacin and COX-1 inhibitor, SC-560, while COX-2 inhibitor, NS-398, and iNOS inhibitor, 1400W, had no effect. The effect of L-NAME was reflected in the inhibition of ghrelin-induced cell capacity for NO production, cPLA(2) activation and PGE2 generation, whereas indomethacin caused only the inhibition in PGE2. Moreover, the ghrelin-induced up-regulation in AA release was reflected in the cPLA(2) phosphorylation and S-nitrosylation. Inhibition in ghrelin-induced S-nitrosylation was attained with L-NAME, whereas the ERK inhibitor, PD98059, caused the blockage in cPLA(2) protein phosphorylation as well as S-nitrosylation. Thus, ghrelin protection of salivary gland cells against ethanol involves cNOS-derived NO induction of cPLA(2) activation through S-nitrosylation for the increase in AA release at the site of COX-1 action for PGE2 synthesis.

  7. Ghrelin fluctuation, what determines its production?

    Institute of Scientific and Technical Information of China (English)

    Xuefeng Yin; Yin Li; Geyang Xu; Wenjiao An; Weizhen Zhang

    2009-01-01

    Ghrelin, a 28 amino acid gut brain peptide, acts as an endogenous ligand for its receptor, the growth hormone secretagogue receptor, to exercise a variety of functions ranging from stimulation of growth hormone secretion, regulation of appetite and energy metabolism, and cell protection to modulation of inflammation. This review summarizes the advance in the regulation of ghrelin expression and secretion. We introduce the structure of ghrelin promoter, the processing and modification of ghrelin precursor, and the regulation mechanism in these processes. Then we discuss factors found to be important in the regulation of ghrelin production, including nutrients, hormones, and autonomic nervous system. Finally, we outline the alteration in the level of ghrelin in certain physiological and pathological status.

  8. Ghrelin: Central and Peripheral Implications in Anorexia Nervosa

    Directory of Open Access Journals (Sweden)

    Mathieu eMéquinion

    2013-02-01

    Full Text Available Food intake and associated disorders are gaining large emphasis in our societies due to their dramatic physiological and psychological consequences on health. Chronic food restriction is a major symptom described in restrictive anorexia nervosa (AN patients. This disease, mostly observed in young women is the third cause of chronic illness in teenagers. It leads to central and/or peripheral reprogramming that permits the organism to endure the reduced energy supplies. These drastic conditions induce severe weight loss, metabolic disturbances, infertility, osteopenia and osteoporosis. Moreover, increasing number of arguments consider AN as an addictive behaviour to food deprivation or weight loss or physical activity, usually associated with mood disorders. This suggests a potential alteration of the central reward system. Significant changes in hormones involved in energy metabolism, regulation of feeding behaviours and bone formation are described in AN patients, but also in animal models presenting a strong face validity. Surprisingly, the plasma levels of ghrelin, an orexigenic hormone, are increased. This hormone acts centrally to modulate food intake, but also peripherally mainly to maintain blood glucose and to regulate gastric motility. Such increase in plasma ghrelin levels seems paradoxical in light of the restrained eating adopted by these AN patients, but adaptive. The aim of this review is to describe the role played by ghrelin in AN focusing on its central vs peripheral action. The chronic food restriction induces both in AN patients and in rodent models a profound alteration in the « ghrelin » signal integration that lead to the development of inappropriate behaviours like hyperactivity or addiction to food starvation and therefore a greater depletion in energy reserves. The question of a transient insensitivity to ghrelin and/or a potential metabolic reprogramming is discussed in regard of new clinical treatments currently

  9. Exogenous and endogenous ghrelin counteracts GLP-1 action to stimulate cAMP signaling and insulin secretion in islet β-cells.

    Science.gov (United States)

    Damdindorj, Boldbaatar; Dezaki, Katsuya; Kurashina, Tomoyuki; Sone, Hideyuki; Rita, Rauza; Kakei, Masafumi; Yada, Toshihiko

    2012-07-30

    We studied interactive effects of insulinotropic GLP-1 and insulinostatic ghrelin on rat pancreatic islets. GLP-1 potentiated glucose-induced insulin release and cAMP production in isolated islets and [Ca(2+)](i) increases in single β-cells, and these potentiations were attenuated by ghrelin. Ghrelin suppressed [Ca(2+)](i) responses to an adenylate cyclase activator forskolin. Moreover, GLP-1-induced insulin release and cAMP production were markedly enhanced by [D-lys(3)]-GHRP-6, a ghrelin receptor antagonist, in isolated islets. These results indicate that both exogenous and endogenous islet-derived ghrelin counteracts glucose-dependent GLP-1 action to increase cAMP production, [Ca(2+)](i) and insulin release in islet β-cells, positioning ghrelin as a modulator of insulinotropic GLP-1.

  10. Ghrelin and PYY levels in adolescents with severe obesity: effects of weight loss induced by long-term exercise training and modified food habits.

    Science.gov (United States)

    Gueugnon, Carine; Mougin, Fabienne; Nguyen, Nhu Uyen; Bouhaddi, Malika; Nicolet-Guénat, Marie; Dumoulin, Gilles

    2012-05-01

    This study investigated (a) changes in ghrelin and peptide YY (PYY) concentrations during a weight reduction programme and (b) baseline ghrelin and PYY levels as predictors of weight loss in 32 severely obese adolescents (BMI z score = 4.1). Subjects spent an academic year in an institution for childhood obesity. Fasting ghrelin and PYY, leptin, insulin levels and insulin resistance were measured at baseline (month 0) and during the programme (months 3, 6, 9). In addition, 15 normal-weight teenagers served as reference for the baseline assessments. At baseline, obese teenagers had lower ghrelin and PYY concentrations than normal-weight adolescents (P teenagers, associated with an increase in ghrelin (apparent from month 6; P adolescents with severe obesity, a long-term combination of supervised aerobic exercises and a balanced diet led to weight reduction and increased ghrelin concentrations, without any change in PYY concentrations. Moreover, baseline PYY concentrations might be considered as predictors of weight loss.

  11. Bitter taste receptors and α-gustducin regulate the secretion of ghrelin with functional effects on food intake and gastric emptying.

    Science.gov (United States)

    Janssen, Sara; Laermans, Jorien; Verhulst, Pieter-Jan; Thijs, Theo; Tack, Jan; Depoortere, Inge

    2011-02-01

    Ghrelin is a hunger hormone with gastroprokinetic properties but the factors controlling ghrelin secretion from the stomach are unknown. Bitter taste receptors (T2R) and the gustatory G proteins, α-gustducin (gust) and α-transducin, are expressed in the gut and are involved in the chemosensation of nutrients. This study aimed to investigate whether T2R-agonists affect (i) ghrelin release via α-gustducin and (ii) food intake and gastric emptying via the release of ghrelin. The mouse stomach contains two ghrelin cell populations: cells containing octanoyl and desoctanoyl ghrelin, which were colocalized with α-gustducin and α-transducin, and cells staining for desoctanoyl ghrelin. Gavage of T2R-agonists increased plasma octanoyl ghrelin levels in WT mice but the effect was partially blunted in gust(-/-) mice. Intragastric administration of T2R-agonists increased food intake during the first 30 min in WT but not in gust(-/-) and ghrelin receptor knockout mice. This increase was accompanied by an increase in the mRNA expression of agouti-related peptide in the hypothalamus of WT but not of gust(-/-) mice. The temporary increase in food intake was followed by a prolonged decrease (next 4 h), which correlated with an inhibition of gastric emptying. The delay in emptying, which was partially counteracted by ghrelin, was not mediated by cholecystokinin and GLP-1 but involved a direct inhibitory effect of T2R-agonists on gastric contractility. This study is unique in providing functional evidence that activation of bitter taste receptors stimulates ghrelin secretion. Modulation of endogenous ghrelin levels by tastants may provide novel therapeutic applications for the treatment of weight -and gastrointestinal motility disorders.

  12. Ghrelin and motilin in the gastrointestinal system.

    Science.gov (United States)

    Chen, Chih-Yen; Tsai, Chang-Youh

    2012-01-01

    Human ghrelin and human motilin, belonging to the ghrelin/motilin-related peptide family, share 36% amino acid sequence identity, while the human ghrelin receptor exhibits a remarkable 50% overall identity with the human motilin receptor. In addition to their structural resemblance, ghrelin and motilin are the only two mammalian hormones known to decrease in the postprandial period. Ghrelin and motilin participate in initiating the migrating motor complex in the stomach, and stimulate gastrointestinal motility, accelerate gastric emptying, and induce "gastric hunger". In addition to modulating the release of growth hormone and gut motility, ghrelin plays a crucial role in the secretion and protection of the stomach and colon. Ghrelin mimetics and motilin agonists are currently being developed to reverse gastrointestinal hypomotility disorders. With additional appetite-enhancing, adiposity-promoting, and anti-inflammatory effects, ghrelin and rikkunshito (a traditional Japanese herb enhancing acyl ghrelin signaling) are superior to motilin in the treatment of cancer-related anorexia and cachexia, post-chemotherapy symptoms, rheumatological diseases, age-related frailty, as well as post-operative, septic, and post-burn gut ileus.

  13. Bicuculline, a GABAA-receptor antagonist, blocked HPA axis activation induced by ghrelin under an acute stress.

    Science.gov (United States)

    Gastón, M S; Cid, M P; Salvatierra, N A

    2017-03-01

    Ghrelin is a peptide of 28 amino acids with a homology between species, which acts on the central nervous system to regulate different actions, including the control of growth hormone secretion and metabolic regulation. It has been suggested that central ghrelin is a mediator of behavior linked to stress responses and induces anxiety in rodents and birds. Previously, we observed that the anxiogenic-like behavior induced by ghrelin injected into the intermediate medial mesopallium (IMM) of the forebrain was blocked by bicuculline (a GABAA receptor competitive antagonist) but not by diazepam (a GABAA receptor allosteric agonist) in neonatal meat-type chicks (Cobb). Numerous studies have indicated that hypothalamic-pituitary-adrenal (HPA) axis activation mediates the response to stress in mammals and birds. However, it is still unclear whether this effect of ghrelin is associated with HPA activation. Therefore, we investigated whether anxiety behavior induced by intra-IMM ghrelin and mediated through GABAA receptors could be associated with HPA axis activation in the neonatal chick. In the present study, in an Open Field test, intraperitoneal bicuculline methiodide blocked anxiogenic-like behavior as well as the increase in plasma ACTH and corticosterone levels induced by ghrelin (30pmol) in neonatal chicks. Moreover, we showed for the first time that a competitive antagonist of GABAA receptor suppressed the HPA axis activation induced by an anxiogenic dose of ghrelin. These results show that the anxiogenic ghrelin action involves the activation of the HPA axis, with a complex functional interaction with the GABAA receptor.

  14. Enhanced ghrelin secretion in the cephalic phase of food ingestion in women with bulimia nervosa.

    Science.gov (United States)

    Monteleone, Palmiero; Serritella, Cristina; Scognamiglio, Pasquale; Maj, Mario

    2010-02-01

    In humans, the cephalic phase response to food ingestion consists mostly of vagal efferent activation, which promotes the secretion of entero-pancreatic hormones, including ghrelin. Since symptomatic patients with bulimia nervosa (BN) are characterized by increased vagal tone, we hypothesized an enhanced ghrelin secretion in the cephalic phase of vagal stimulation. Therefore, we investigated ghrelin response to modified sham feeding (MSF) in both BN and healthy women. Six drug-free BN women and 7 age-matched healthy females underwent MSF with initially seeing and smelling a meal, and then chewing the food without swallowing it. Blood samples were drawn immediately before and after MSF for hormone assay. Circulating ghrelin increased after MSF in both groups with BN individuals exhibiting a greater ghrelin increase, which positively correlated with the patients' weekly frequency of binge-purging. These results show for the first time an increased ghrelin secretion in the cephalic phase of vagal stimulation in symptomatic BN patients, likely resulting in a potentiation of the peripheral hunger signal, which might contribute to their aberrant binge-purging behavior.

  15. Effects of Wen Dan Tang on insomnia-related anxiety and levels of the brain-gut peptide Ghrelin

    Institute of Scientific and Technical Information of China (English)

    Liye Wang; Binghe Guan; Xiaolan Liu; Yuehan Song; Feng Li; Yan Liu; Jie Ma; Meng Mao; Fengzhi Wu; Ying Wu; Sinai Li

    2014-01-01

    Ghrelin, a brain-gut peptide that induces anxiety and other abnormal emotions, contributes to the effects of insomnia on emotional behavior. In contrast, the traditional Chinese Medi-cine remedy Wen Dan Tang reduces insomnia-related anxiety, which may perhaps correspond to changes in the brain-gut axis. This suggests a possible relationship between Wen Dan Tang’s pharmacological mechanism and the brain-gut axis. Based on this hypothesis, a sleep-deprived rat model was induced and Wen Dan Tang was administered using oral gavage during model es-tablishment. Wen Dan Tang signiifcantly reduced insomnia-related anxiety and prevented Ghrelin level decreases following sleep deprivation, especially in the hypothalamus. Increased expression of Ghrelin receptor mRNA in the hypothalamus was also observed, suggesting that reduced anxi-ety may be a result of Wen Dan Tang’s regulation of Ghrelin-Ghrelin receptors.

  16. H. pylori Infection

    Science.gov (United States)

    ... think you may have a high risk of stomach cancer, talk to your doctor. Together you can decide whether you may benefit from H. pylori screening. References H. pylori and peptic ulcers. National Institute ...

  17. In vivo characterization of high Basal signaling from the ghrelin receptor

    DEFF Research Database (Denmark)

    Petersen, Pia Steen; Woldbye, David P D; Madsen, Andreas Nygaard;

    2009-01-01

    in vivo, we used intracerebroventricular administration by osmotic pumps of a peptide [D-Arg(1), D-Phe(5), D-Trp(7,9), Leu(11)]-substance P. This peptide selectively displays inverse agonism at the ghrelin receptor as compared with an inactive control peptide with just a single amino acid substitution...... agonist. In a hypothalamic cell line that endogenously expresses the ghrelin receptor, we observed high basal activity of the cAMP response element binding protein, an important signaling transduction pathway for appetite regulation. The activation was further increased by ghrelin administration...... and decreased by administration of the inverse agonist. It is suggested that the high constitutive signaling activity is important for the in vivo function of the ghrelin receptor in the control of food intake and body weight....

  18. The effect of feeding frequency on insulin and ghrelin responses in human subjects

    DEFF Research Database (Denmark)

    Solomon, Thomas; Chambers, Edward S; Jeukendrup, Asker E

    2008-01-01

    Recent work shows that increased meal frequency reduces ghrelin responses in sheep. Human research suggests there is an interaction between insulin and ghrelin. The effect of meal frequency on this interaction is unknown. Therefore, we investigated the effect of feeding frequency on insulin...... and ghrelin responses in human subjects. Five healthy male volunteers were recruited from the general population: age 24 (SEM 2)years, body mass 75.7 (SEM 3.2) kg and BMI 23.8 (SEM 0.8) kg/m(2). Volunteers underwent three 8-h feeding regimens: fasting (FAST); low-frequency(two) meal ingestion (LOFREQ(MEAL......)); high-frequency (twelve) meal ingestion (HIFREQ(MEAL)). Meals were equi-energetic within trials,consisting of 64% carbohydrate, 23% fat and 13% protein. Total energy intake was equal between feeding trials. Total area under the curve for serum insulin and plasma ghrelin responses did not differ between...

  19. Urocortin 1 reduces food intake and ghrelin secretion via CRF(2) receptors.

    Science.gov (United States)

    Yakabi, Koji; Noguchi, Masamichi; Ohno, Shino; Ro, Shoki; Onouchi, Tsuneko; Ochiai, Mitsuko; Takabayashi, Hidehiko; Takayama, Kiyoshige; Harada, Yumi; Sadakane, Chiharu; Hattori, Tomohisa

    2011-07-01

    Although it is known that urocortin 1 (UCN) acts on both corticotropin-releasing factor receptors (CRF(1) and CRF(2)), the mechanisms underlying UCN-induced anorexia remain unclear. In contrast, ghrelin, the endogenous ligand for the growth hormone secretagogue receptor, stimulates food intake. In the present study, we examined the effects of CRF(1) and CRF(2) receptor antagonists (CRF(1)a and CRF(2)a) on ghrelin secretion and synthesis, c-fos mRNA expression in the caudal brain stem, and food intake following intracerebroventricular administration of UCN. Eight-week-old, male Sprague-Dawley rats were used after 24-h food deprivation. Acylated and des-acylated ghrelin levels were measured by enzyme-linked immunosorbent assay. The mRNA expressions of preproghrelin and c-fos were measured by real-time RT-PCR. The present study provided the following important insights into the mechanisms underlying the anorectic effects of UCN: 1) UCN increased acylated and des-acylated ghrelin levels in the gastric body and decreased their levels in the plasma; 2) UCN decreased preproghrelin mRNA levels in the gastric body; 3) UCN-induced reduction of plasma ghrelin and food intake were restored by CRF(2)a but not CRF(1)a; 4) UCN-induced increase of c-fos mRNA levels in the caudal brain stem containing the nucleus of the solitary tract (NTS) was inhibited by CRF(2)a; and 5) UCN-induced reduction of food intake was restored by exogenous ghrelin and rikkunshito, an endogenous ghrelin secretion regulator. Thus, UCN increases neuronal activation in the caudal brain stem containing NTS via CRF(2) receptors, which may be related to UCN-induced inhibition of both ghrelin secretion and food intake.

  20. The role of the central ghrelin system in reward from food and chemical drugs.

    Science.gov (United States)

    Dickson, Suzanne L; Egecioglu, Emil; Landgren, Sara; Skibicka, Karolina P; Engel, Jörgen A; Jerlhag, Elisabet

    2011-06-20

    Here we review recent advances that identify a role for the central ghrelin signalling system in reward from both natural rewards (such as food) and artificial rewards (that include alcohol and drugs of abuse). Whereas ghrelin emerged as a stomach-derived hormone involved in energy balance, hunger and meal initiation via hypothalamic circuits, it now seems clear that it also has a role in motivated reward-driven behaviours via activation of the so-called "cholinergic-dopaminergic reward link". This reward link comprises a dopamine projection from the ventral tegmental area (VTA) to the nucleus accumbens together with a cholinergic input, arising primarily from the laterodorsal tegmental area. Ghrelin administration into the VTA or LDTg activates the "cholinergic-dopaminergic" reward link, suggesting that ghrelin may increase the incentive value of motivated behaviours such as reward-seeking behaviour ("wanting" or "incentive motivation"). Further, direct injection of ghrelin into the brain ventricles or into the VTA increases the consumption of rewarding foods as well as alcohol in mice and rats. Studies in rodents show beneficial effects of ghrelin receptor (GHS-R1A) antagonists to suppress the intake of palatable food, to reduce preference for caloric foods, to suppress food reward and motivated behaviour for food. They have also been shown to reduce alcohol consumption, suppress reward induced by alcohol, cocaine and amphetamine. Furthermore, variations in the GHS-R1A and pro-ghrelin genes have been associated with high alcohol consumption, smoking and increased weight gain in alcohol dependent individuals as well as with bulimia nervosa and obesity. Thus, the central ghrelin signalling system interfaces neurobiological circuits involved in reward from food as well as chemical drugs; agents that directly or indirectly suppress this system emerge as potential candidate drugs for suppressing problematic over-eating that leads to obesity as well as for the

  1. Helicobacter Pylori Infections

    Science.gov (United States)

    Helicobacter pylori (H. pylori) is a type of bacteria that causes infection in the stomach. It is found in about two-thirds of ... or stool to see if it contains H. pylori. The best treatment is a combination of antibiotics ...

  2. Gastric motor effects of ghrelin and growth hormone releasing peptide 6 in diabetic mice with gastroparesis

    Institute of Scientific and Technical Information of China (English)

    Wen-Cai Qiu; Zhi-Gang Wang; Wei-Gang Wang; Jun Yan; Qi Zheng

    2008-01-01

    AIM:To investigate the potential therapeutic significance of ghrelin and growth hormone releasing peptide 6(GHRP-6) in diabetic mice with gastric motility disorders.METHODS:A diabetic mouse model was established by intraperitoneal (ip) injection of alloxan.Diabetic mice were injected ip with ghrelin or GHRP-6 (20-200 μg/kg),and the effects on gastric emptying were measured after intragastric application of phenol red.The effect of atropine,NG-nitro-L-arginine methyl ester hydrochloride (L-NAME) or D-Lys3-GHRP-6 (a growth hormone secretagogue receptor (GHS-R) antagonist) on the gastroprokinetic effect of ghrelin or GHRP-6 (100 μg/kg)was also investigated.The effects of ghrelin or GHRP-6(0.01-10 μmol/L) on spontaneous or carbachol-induced contractile amplitude were also investigated in vitro,in gastric fundic circular strips taken from diabetic mice.The presence of growth hormone secretagogue receptor la transcripts in the fundic strips of diabetic mice was detected by reverse transcriptase polymerase chain reaction (RT-PCR).RESULTS:We established a diabetic mouse model with delayed gastric emptying.Ghrelin and GHRP-6accelerated gastric emptying in diabetic mice with gastroparesis.In the presence of atropine or L-NAME,which delayed gastric emptying,ghrelin and GHRP-6(100 μg/kg) failed to accelerate gastric emptying.D-Lys3-GHRP-6 also delayed gastric emptying induced by the GHS-R agonist.Ghrelin and GHRP-6 increased the carbachol-induced contractile amplitude in gastric fundic strips taken from diabetic mice.RT-PCR confirmed the presence of GHS-R mRNA in the strip preparations.CONCLUSION:Ghrelin and GHRP-6 increase gastric emptying in diabetic mice with gastroparesis,perhaps by activating peripheral cholinergic pathways in the enteric nervous system.

  3. Ghrelin modulates testicular germ cells apoptosis and proliferation in adult normal rats

    Energy Technology Data Exchange (ETDEWEB)

    Kheradmand, Arash, E-mail: arashkheradmand@yahoo.com [Department of Clinical Sciences, School of Veterinary Medicine, Lorestan University, P.O. Box: 465, Khorram Abad (Iran, Islamic Republic of); Dezfoulian, Omid [Department of Pathobiology, School of Veterinary Medicine, Lorestan University, Khorram Abad (Iran, Islamic Republic of); Alirezaei, Masoud [Division of Biochemistry, School of Veterinary Medicine, Lorestan University, P.O. Box: 465, Khorram Abad (Iran, Islamic Republic of); Rasoulian, Bahram [Razi Herbal Medicine Research Center, Lorestan University of Medical Sciences, Khorram Abad (Iran, Islamic Republic of)

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer Spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. Black-Right-Pointing-Pointer Numerous studies have documented the direct action of ghrelin in the modulation of apoptosis in different cell types. Black-Right-Pointing-Pointer Ghrelin may be considered as a modulator of spermatogenesis in normal adult rats. Black-Right-Pointing-Pointer Ghrelin may be potentially implicated for abnormal spermatogenesis in some testicular germ cell tumors. -- Abstract: Under normal condition in the most mammals, spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. The present study was designed to determine the effects of ghrelin treatment on in vivo quality and quantity expression of apoptosis and proliferation specific indices in rat testicular germ cells. Twenty eight adult normal rats were subdivided into equal control and treatment groups. Treatment group received 3 nmol of ghrelin as subcutaneous injection for 30 consecutive days or vehicle to the control animals. The rats from each group (n = 7) were killed on days 10 and 30 and their testes were taken for immunocytochemical evaluation and caspase-3 assay. Immunohistochemical analysis indicated that the accumulations of Bax and PCNA peptides are generally more prominent in spermatocytes and spermatogonia of both groups. Likewise, the mean percentage of immunoreactive spermatocytes against Bax increased (P < 0.01) in the ghrelin-treated group on day 10, while despite of 30% increment in the Bax level of spermatocytes in the treated rats on day 30, however, it was not statistically significant. During the experimental period, only a few spermatogonia represented Bax expression and the changes of Bax immunolabling cells were negligible upon ghrelin treatment. Likewise, there were immunostaining cells against Bcl-2 in each germ cell neither in the control nor in the treated animals. In fact

  4. Ghrelin regulates GLP-1 production through mTOR signaling in L cells.

    Science.gov (United States)

    Xu, Geyang; Hong, Xiaosi; Tang, Hong; Jiang, Sushi; Liu, Fenting; Shen, Zhemin; Li, Ziru; Zhang, Weizhen

    2015-11-15

    Glucagon-like peptide (GLP-1), an intestinal incretin produced in L-cells and released in response to meal intake, functions to promote insulin secretion and to decrease plasma glucose. Ghrelin is an orexigenic hormone critical for glucose homeostasis. The molecular mechanism by which ghrelin alters GLP-1 production remains largely unknown. Here we showed that ghrelin attenuates GLP-1 production through mTOR signaling. In GHSR1a null mice, ileal mTOR signaling, proglucagon and circulating GLP-1 were significantly increased. Antagonism of the GHSR1a by D-Lys-3-GHRP-6 increased GLP-1 synthesis and release in STC-1 cells. Treatment of STC-1 cells with ghrelin decreased the production of GLP-1. This effect was associated with a significant inhibition of mTOR signaling. Overexpression of ghrelin inhibited proglucagon promoter activity and GLP-1 production. Inhibition of mTOR activity by mTOR siRNA blocked D-Lys-3-GHRP-6 induced GLP-1 production in STC-1 cells. Our results suggest that mTOR signaling mediates the inhibitory effect of ghrelin on GLP-1 production.

  5. Aging effects on exercise-induced alternations in plasma acylated ghrelin and leptin in male rats.

    Science.gov (United States)

    Hsu, Ya-Wen; Pan, Yi-Ju; Cho, Yu-Min; Liou, Tsan-Hon; Chou, Pesus; Wang, Paulus S

    2011-05-01

    Ghrelin and exercise have been known to stimulate the release of growth hormone which is related to the glucose metabolism. However, the age effects of exercise on ghrelin in energy consumption remain unclear. Young (3 month old) and middle-aged (12 month old) Sprague-Dawley male rats were overnight fasted, and then randomly partitioned into exercise and control groups. Exercise groups swam for 20 min in 25°C water. Rats immersed in 25°C water for 20 min were used as control animals. All blood samples were collected before and 10, 20, 30, and 60 min after initiation of exercise via the right jugular vein. Our results indicated that the swimming regimen decreased the secretion of acylated ghrelin and insulin, but increased the secretion of leptin, lactate, and glucose. In addition, exercise significantly amplified the inverse correlation between leptin and acylated ghrelin (r ghrelin. A 20-min exercise regimen decreased acylated ghrelin and increased leptin with inverse correlation between them which was strengthened during exercise, but were not influenced by age.

  6. Changes in blood pancreatic polypeptide and ghrelin concentrations in response to feeding in sheep.

    Science.gov (United States)

    Takahashi, H; Kurose, Y; Suzuki, Y; Kojima, M; Yamaguchi, T; Yoshida, Y; Azuma, Y; Sugino, T; Kojima, M; Kangawa, K; Hasegawa, Y; Kobayashi, S

    2010-06-01

    The roles of pancreatic polypeptide (PP) have not been determined in ruminant animals. The aim of the present study was to examine the role of PP in the regulation of ghrelin secretion in sheep. Two experiments were conducted using four 2-yr-old Suffolk wethers fed a maintenance diet of alfalfa hay cubes. In Exp. 1, the effects of feeding on blood ghrelin and PP concentrations were examined in scheduled-fed sheep. Blood samples were collected every 10 min from 30 min before to 360 min after feeding. Plasma PP concentrations were transiently increased from the preprandial average value to the values from 30 to 60 min after feeding and gradually decreased (P infusion on ghrelin secretion were examined in feed-deprived sheep. The animals were deprived of feed for 48 h before PP infusion. The PP-treated group intravenously received synthetic bovine PP at a rate of 10 pmol.kg(-1 )of BW.min(-1) for 180 min. Blood samples were collected every 10 min from 30 min before to 180 min after the commencement of PP infusion. Plasma PP concentrations reached a plateau within 30 min after the commencement of PP infusion. Plasma ghrelin concentrations were decreased (P = 0.002, 0.016, 0.007) by PP infusion at 160, 170, and 180 min, respectively. In conclusion, plasma ghrelin and PP concentrations were decreased and increased, respectively, in response to feeding in ruminant animals. Furthermore, PP could depress ghrelin secretion.

  7. Treatment of TBI and Concomitant Hemorrhage with Ghrelin

    Science.gov (United States)

    2010-07-01

    battlefield setting. 15. SUBJECT TERMS Traumatic brain injury ; hemorrhagic shock; ghrelin; treatment 16. SECURITY CLASSIFICATION OF: U 17...hemorrhagic shock. 2. Ghrelin treatment improves sensorimotor and reflex function after traumatic brain injury and uncontrolled hemorrhagic shock...3. Ghrelin treatment reduces cortical apoptosis after traumatic brain injury and uncontrolled hemorrhagic shock. 4. Ghrelin treatment

  8. The influence of pretreatment with ghrelin on the development of acetic-acid-induced colitis in rats.

    Science.gov (United States)

    Maduzia, D; Matuszyk, A; Ceranowicz, D; Warzecha, Z; Ceranowicz, P; Fyderek, K; Galazka, K; Dembinski, A

    2015-12-01

    Ghrelin has been primarily shown to exhibit protective and therapeutic effect in the gut. Pretreatment with ghrelin inhibits the development of acute pancreatitis and accelerates pancreatic recovery in the course of this disease. In the stomach, ghrelin reduces gastric mucosal damage induced by ethanol, stress or alendronate, as well as accelerates the healing of acetic acid-induced gastric and duodenal ulcer. The aim of present studies was to investigate the effect of pretreatment with ghrelin on the development of acetic acid-induced colitis. Studies have been performed on male Wistar rats. Animals were treated intraperitoneally with saline (control) or ghrelin (4, 8 or 16 nmol/kg/dose). Saline or ghrelin was given twice: 8 and 1 h before induction of colitis. Colitis was induced by a rectal enema with 1 ml of 4% solution of acetic acid and the severity of colitis was assessed 1 or 24 hours after induction of inflammation. Rectal administration of acetic acid induced colitis in all animals. Damage of colonic wall was seen at the macroscopic and microscopic level. This effect was accompanied by a reduction in colonic blood flow and mucosal DNA synthesis. Moreover, induction of colitis significantly increased mucosal concentration of pro-inflammatory interleukin-1β (IL-1β), activity of myeloperoxidase and concentration of malondialdehyde (MDA). Mucosal activity of superoxide dismutase (SOD) was reduced. Pretreatment with ghrelin reduced the area and grade of mucosal damage. This effect was accompanied by an improvement of blood flow, DNA synthesis and SOD activity in colonic mucosa. Moreover, ghrelin administration reduced mucosal concentration of IL-1β and MDA, as well as decreased mucosal activity of myeloperoxidase. Administration of ghrelin protects the large bowel against the development of the acetic acid-induced colitis and this effect seems to be related to the ghrelin-evoked anti-inflammatory and anti-oxidative effects.

  9. THE EFFECTS OF Syzygium aromaticum-DERIVED TRITERPENES ON GASTROINTESTINAL GHRELIN EXPRESSION IN STREPTOZOTOCIN-INDUCED DIABETIC RATS.

    Science.gov (United States)

    Luvuno, Mluleki; Mbongwa, Hlengiwe Prosperity; Khathi, Andile

    2016-01-01

    Diabetic polyphagia has been associated with elevated plasma ghrelin levels in experimental type 1 diabetes. This increase in food consumption contributes to chronic hyperglycaemia in diabetes thus contributing to the development of micro- and macrovascular complications. We have reported that plant-derived oleanolic acid (OA) and maslinic acid (MA) reduce blood glucose levels, in part, through the inhibition of intestinal carbohydrate hydrolyzing enzymes and glucose transporters. However, their effects on food intake and plasma ghrelin concentrations are unclear. Accordingly, we investigated the effects of these triterpenes on food intake and ghrelin expression in streptozotocin-induced diabetic rats. The effects of OA and MA on blood glucose concentration; food and water intake were monitored over five weeks after which plasma ghrelin concentrations were measured. Additionally, the expression of ghrelin in the various sections of the GIT was determined using Western blot analysis. Ghrelin concentrations in untreated STZ-induced diabetic rats were significantly higher in comparison to the non-diabetic control. Interestingly, the administration of OA and MA reduced food intake, blood glucose levels and plasma ghrelin levels in STZ-induced diabetic rats. This was further complemented by significant reductions in the gastrointestinal expression of ghrelin suggesting that the anti-diabetic properties of these triterpenes are mediated, in part, through the reduction of food intake and the modulation of ghrelin expression. The findings of the study suggest that the control of food intake through the reduction of ghrelin expression by plant-derived OA and MA may constitute an avenue of glycaemic control in diabetes mellitus.

  10. Participation of ghrelin signalling in the reciprocal regulation of hypothalamic NPY/POMC-mediated appetite control in amphetamine-treated rats.

    Science.gov (United States)

    Yu, Ching-Han; Chu, Shu-Chen; Chen, Pei-Ni; Hsieh, Yih-Shou; Kuo, Dong-Yih

    2017-02-14

    Hypothalamic neuropeptide Y (NPY) and proopiomelanocortin (POMC) have been documented to participate in amphetamine (AMPH)-induced appetite suppression. This study investigated whether ghrelin signalling is associated with changes in NPY/POMC-mediated appetite control. Rats were given AMPH daily for four days, and changes in food intake, body weight, plasma ghrelin, hypothalamic NPY, melanocortin 3 receptor (MC3R), ghrelin O-acyltransferase (GOAT), acyl ghrelin (AG) and ghrelin receptor (GHSR1a) were examined and compared. Food intake, body weight and NPY expression decreased, while MC3R expression increased and expressed reciprocally to NPY expression during AMPH treatment. Plasma ghrelin and hypothalamic AG/GOAT/GHSR1a expression decreased on Day 1 and Day 2, which was associated with the positive energy metabolism, and returned to normal levels on Day 3 and Day 4, which was associated with the negative energy metabolism; this expression pattern was similar to that of NPY. Infusion with a GHSR1a antagonist or an NPY antisense into the brain enhanced the decrease in NPY and AG/GOAT/GHSR1a expression and the increase in MC3R expression compared to the AMPH-treated group. Peripheral ghrelin and the central ghrelin system participated in the regulation in AMPH-induced appetite control. These results shed light on the involvement of ghrelin signalling in reciprocal regulation of NPY/POMC-mediated appetite control and may prove useful for the development of anti-obesity drugs.

  11. Prevalence of Helicobacter Pylori Infection Among Patients ...

    African Journals Online (AJOL)

    variables such as age, sex, socioeconomic status, dietary habits, genetic, and immunological ... Age distribution of H. pylori infection did not show any trend towards increase or .... infection in dyspeptic patients in Iran. Gastroenterol Insights.

  12. Ghrelin Attenuates Liver Fibrosis through Regulation of TGF-β1 Expression and Autophagy

    Directory of Open Access Journals (Sweden)

    Yuqing Mao

    2015-09-01

    Full Text Available Ghrelin is a stomach-derived growth hormone secretagogue that promotes various physiological effects, including energy metabolism and amelioration of inflammation. The purpose of this study was to investigate the protective mechanism of ghrelin against liver fibrosis. Liver fibrosis was induced in C57BL/6 mice by intraperitoneal injection of CCl4 (2.0 mL/kg of 10% CCl4 v/v solution in peanut oil two times per week for eight weeks. Ghrelin (10 μg/kg was intraperitoneally injected two times per week for eight weeks. A second murine liver fibrosis model was induced by bile duct ligation (BDL and concurrent ghrelin administration for four weeks. Hematoxylin eosin (H&E, and Masson’s trichrome were used to detect pathological changes to liver tissue. Western blotting was used to detect protein levels of transforming growth factor (TGF-β1, phosphorylated Smad3 (p-Smad3, I-collage, α-smooth muscle actin (α-SMA, matrix metalloproteinases (MMPs 2, tissue inhibitor of matrix metalloproteinases (TIMPs 1, phosphorylated NF-κB (p-NF-κB, and microtubule-associated protein light chain 3 (LC3. In addition, qRT-PCR was used to detect mRNA levels of TGF-β1, I-collage, α-SMA, MMP2, TIMP1 and LC3, while levels of TGF-β1, p-Smad3, I-collage, α-SMA, and LC3 were detected immunohistochemically. Levels of aspartate aminotransferase and alanine aminotransferase were significantly decreased by ghrelin treatment. Ghrelin administration also significantly reduced the extent of pathological changes in both murine liver fibrosis models. Expression levels of I-collage and α-SMA in both models were clearly reduced by ghrelin administration. Furthermore, ghrelin treatment decreased protein expression of TGF-β1 and p-Smad3. The protein levels of NF-κB and LC3 were increased in the CCl4- and BDL-treatment groups but were significantly reduced following ghrelin treatment. In addition, ghrelin inhibited extracellular matrix formation by decreasing NF-κB expression

  13. Ghrelin upregulates PepT1 activity in the small intestine epithelium of rats with sepsis.

    Science.gov (United States)

    Liu, Jingquan; Shi, Bin; Shi, Kai; Ma, Guoguang; Zhang, Hongze; Lou, Xiaoli; Liu, Hongxiang; Wan, Shengxia; Liang, Dongyu

    2017-02-01

    Sepsis causes nutritional substrate malabsorption; hence, preventing gut barrier problems and improving the nutritional status in sepsis is a compelling issue. We tested whether ghrelin administration affects peptide transporter 1 (PepT1) activity in the intestinal epithelium of rats with sepsis. Sixty male Sprague-Dawley rats were randomly divided into sham-operated, sepsis, and ghrelin-treated groups. The cecum of sham-operated rats was separated after laparotomy without ligation and perforation. Sepsis group rats underwent cecal ligation and puncture (CLP). Mucosal specimens were used for immunohistochemstry, real-time PCR, and western blotting to detect PepT1 distribution, and mRNA and protein expression levels, respectively. TNF-α, IL-1β, and ghrelin levels were estimated in serum and intestinal mucosal tissue by ELISA. High-performance liquid chromatography was used to measure PepT1 uptake by the epithelial cells. Moreover, survival, body weight, and food intake of the rats were recorded during the 7-day treatment period. All rats in the sham-operated group survived, and 80% of rats in the sepsis group died within 7d of CLP. Treatment with ghrelin attenuated the CLP-induced body weight loss, intestine mucosa damage, and the survival rate was better. In addition, ghrelin attenuated increases in TNF-α and IL-1β production. The expressions of PepT1 mRNA and protein were higher in ghrelin-treated group rats than in sepsis rats. Moreover, the uptake function of PepT1 was better in ghrelin-treated group rats. Ghrelin treatment can reduce the inflammatory response and greatly upregulate the physiological function of PepT1 in intestinal epithelial cells of rats with sepsis. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  14. Association of ghrelin with cardiometabolic risk factors in Iranian adolescents: the CASPIAN-III study

    Science.gov (United States)

    Heshmat, Ramin; Shafiee, Gita; Qorbani, Mostafa; Azizi-Soleiman, Fatemeh; Djalalinia, Shirin; Esmaeil Motlagh, Mohammad; Ardalan, Gelayol; Ahadi, Zeinab; Safari, Omid; Safiri, Saeid; Kelishadi, Roya

    2016-01-01

    Introduction: Current evidence suggests that ghrelin could contribute to the development of metabolic syndrome (MetS) in adults, but limited experience exists in adolescents. This study aims to explore the association of ghrelin levels with the MetS components among Iranian adolescents. Methods: In this case-control study, 32 adolescents with MetS and 148 healthy controls were selected randomly from the childhood and Adolescence Surveillance and Prevention of Adult Non communicable disease (CASPIAN-III) study. MetS was defined according to the Adult Treatment Panel III (ATP III) criteria modified for children and adolescents. Anthropometric measures (including body mass index [BMI], waist circumference [WC] and waist to height ratio [WHtR]), blood pressure (BP) and biochemical data (including fasting blood sugar [FBS], triglyceride [TG], high-density lipoprotein cholesterol [HDL-C], low-density lipoprotein cholesterol [LDL-C], total cholesterol [TC] and gerlin) were measured. Results: Total ghrelin level was significantly higher in students without MetS compared to those with MetS (748.89 ± 85.04 vs. 728.72 ± 90.36 [pg/mL]; P < 0.001). Significant negative correlations were seen between ghrelin levels and BMI, WC, WHtR, TG, and TC. Ghrelin had also relatively strong inverse correlations with FBS (r = −0.59, P< 0.001), LDL-C (r = −0.56, P < 0.001), and positive correlation with HDL-C (r = 0.60, P < 0.001). Compared with the children with MetS, in those without MetS, ghrelin was significantly associated with HDL-C and LDL-C. A decreasing trend was observed in the mean ghrelin level across increasing number of MetS components (P for trend <0.001). Conclusion: We observed a relationship between ghrelin concentration and MetS components in adolescents. PMID:27777695

  15. Ghrelin- and GH-induced insulin resistance

    DEFF Research Database (Denmark)

    Vestergaard, Esben Thyssen; Krag, Morten B; Poulsen, Morten M

    2013-01-01

    Supraphysiological levels of ghrelin and GH induce insulin resistance. Serum levels of retinol-binding protein-4 (RBP4) correlate inversely with insulin sensitivity in patients with type 2 diabetes. We aimed to determine whether ghrelin and GH affect RBP4 levels in human subjects....

  16. Recent Advances in Potential Clinical Application of Ghrelin in Obesity

    Directory of Open Access Journals (Sweden)

    Christine Delporte

    2012-01-01

    Full Text Available Ghrelin is the natural ligand of the growth hormone secretagogue receptor (GHS-R1a. Ghrelin is a 28 amino acid peptide possessing a unique acylation on the serine in position 3 catalyzed by ghrelin O-acyltransferase (GOAT. Ghrelin stimulates growth hormone secretion, but also appetite, food intake, weight gain, and gastric emptying. Ghrelin is involved in weight regulation, obesity, type 2 diabetes, and metabolic syndrome. Furthermore, a better understanding of ghrelin biology led to the identification of molecular targets modulating ghrelin levels and/or its biological effects: GOAT, ghrelin, and GHS-R1a. Furthermore, a recent discovery, showing the involvement of bitter taste receptor T2R in ghrelin secretion and/or synthesis and food intake, suggested that T2R could represent an additional interesting molecular target. Several classes of ghrelin-related pharmacological tools for the treatment of obesity have been or could be developed to modulate the identified molecular targets.

  17. Protective effect of ghrelin on left ventricular remodeling in spontaneously hypertensive rats is associated with the peroxisome proliferator-activated receptor gamma-dependent pathway

    Institute of Scientific and Technical Information of China (English)

    LI Zhao; ZHU Xiao-ying; LI Meng; BAI Ying-long; HU Jian

    2008-01-01

    Background Studies suggested that exogenous ghrelin administration could prevent eady left ventricular remodeling in rats with myocardial infarction.We investigated herein whether ghrelin attenuated left ventricular remodeling induced by hypertension and whether ghrelin's effect was mediated through the peroxisome proliferator-activated receptor gamma (PPAR-γ)-dependent pathway.Methods Spontaneously hypertensive rats (8-week-old males) were randomly divided into three groups with 12 rats in each:ghrelin group (received ghrelin 100 μg/kg subcutaneously (sc) twice daily);ghrelin+GW9662 group (received the PPAR-γ antagonist GW9662 at 2 mg/kg sc,and then ghrelin as above);saline controls.Normal male Wistar Kyoto rats (n=12) served as normal controls.Four weeks later,the effects of ghrelin on cardiac remodeling were evaluated by echocardiographic,hemodynamic,and histopathological examination,and gene expression analysis (PPAR-γ protein and mRNA expression).The serum levels of C-reactive protein (CRP) and tumor necrosis factor (TNF)αa were detected by enzyme linked immunosorbent assay.Results Ghrelin prevented ventricular remodeling,increased PPAR-y expression in the myocardium,suppressed collagen I and collagen III mRNA expression,and also decreased the serum levels of TNF-α,but not CRP.All abovementioned effects of ghrelin were inhibited by GW9662.Conclusion Ghrelin inhibited ventricular remodeling induced by hypertension,and the preventive effects of ghrelin may be mediated by the anti-inflammatory actions of the PPAR-y-dependent pathway.

  18. Suppression of Ghrelin Exacerbates HFCS-Induced Adiposity and Insulin Resistance

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    Xiaojun Ma

    2017-06-01

    Full Text Available High fructose corn syrup (HFCS is widely used as sweetener in processed foods and soft drinks in the United States, largely substituting sucrose (SUC. The orexigenic hormone ghrelin promotes obesity and insulin resistance; ghrelin responds differently to HFCS and SUC ingestion. Here we investigated the roles of ghrelin in HFCS- and SUC-induced adiposity and insulin resistance. To mimic soft drinks, 10-week-old male wild-type (WT and ghrelin knockout (Ghrelin−/− mice were subjected to ad lib. regular chow diet supplemented with either water (RD, 8% HFCS (HFCS, or 10% sucrose (SUC. We found that SUC-feeding induced more robust increases in body weight and body fat than HFCS-feeding. Comparing to SUC-fed mice, HFCS-fed mice showed lower body weight but higher circulating glucose and insulin levels. Interestingly, we also found that ghrelin deletion exacerbates HFCS-induced adiposity and inflammation in adipose tissues, as well as whole-body insulin resistance. Our findings suggest that HFCS and SUC have differential effects on lipid metabolism: while sucrose promotes obesogenesis, HFCS primarily enhances inflammation and insulin resistance, and ghrelin confers protective effects for these metabolic dysfunctions.

  19. Novel mechanisms of growth hormone regulation: growth hormone-releasing peptides and ghrelin

    Directory of Open Access Journals (Sweden)

    A.-M.J. Lengyel

    2006-08-01

    Full Text Available Growth hormone secretion is classically modulated by two hypothalamic hormones, growth hormone-releasing hormone and somatostatin. A third pathway was proposed in the last decade, which involves the growth hormone secretagogues. Ghrelin is a novel acylated peptide which is produced mainly by the stomach. It is also synthesized in the hypothalamus and is present in several other tissues. This endogenous growth hormone secretagogue was discovered by reverse pharmacology when a group of synthetic growth hormone-releasing compounds was initially produced, leading to the isolation of an orphan receptor and, finally, to its endogenous ligand. Ghrelin binds to an active receptor to increase growth hormone release and food intake. It is still not known how hypothalamic and circulating ghrelin is involved in the control of growth hormone release. Endogenous ghrelin might act to amplify the basic pattern of growth hormone secretion, optimizing somatotroph responsiveness to growth hormone-releasing hormone. It may activate multiple interdependent intracellular pathways at the somatotroph, involving protein kinase C, protein kinase A and extracellular calcium systems. However, since ghrelin has a greater ability to release growth hormone in vivo, its main site of action is the hypothalamus. In the current review we summarize the available data on the: a discovery of this peptide, b mechanisms of action of growth hormone secretagogues and ghrelin and possible physiological role on growth hormone modulation, and c regulation of growth hormone release in man after intravenous administration of these peptides.

  20. Ghrelin enhances cue-induced bar pressing for high fat food.

    Science.gov (United States)

    St-Onge, Veronique; Watts, Alexander; Abizaid, Alfonso

    2016-02-01

    Ghrelin is an orexigenic hormone produced by the stomach that acts on growth hormone secretagogue receptors (GHSRs) both peripherally and centrally. The presence of GHSRs in the ventral tegmental area (VTA) suggests that ghrelin signaling at this level may increase the incentive value of palatable foods as well as other natural and artificial rewards. The present investigation sought to determine if ghrelin plays a role in relapse to such foods following a period of abstinence. To achieve this, thirty-six male Long Evans rats were trained to press a lever to obtain a high fat chocolate food reward on a fixed ratio schedule of 1. Following an extinction period during which lever presses were not reinforced, rats were implanted with a cannula connected to a minipump that continuously delivered ghrelin, a GHSR antagonist ([d-Lys-3]-GHRP-6), or saline in the VTA for 14days. One week later, food reward-associated cues, food reward priming, and an overnight fast were used to induce reinstatement of the lever pressing response. Our results indicate that intra-VTA ghrelin enhances cue-induced reinstatement of responses for palatable food pellets. To the extent that the reinstatement paradigm is considered a valid model of relapse in humans, this suggests that ghrelin signaling facilitates relapse to preferred foods in response to food cues through GHSR signaling in the VTA.

  1. From Belly to Brain: Targeting the Ghrelin Receptor in Appetite and Food Intake Regulation.

    Science.gov (United States)

    Howick, Ken; Griffin, Brendan T; Cryan, John F; Schellekens, Harriët

    2017-01-27

    Ghrelin is the only known peripherally-derived orexigenic hormone, increasing appetite and subsequent food intake. The ghrelinergic system has therefore received considerable attention as a therapeutic target to reduce appetite in obesity as well as to stimulate food intake in conditions of anorexia, malnutrition and cachexia. As the therapeutic potential of targeting this hormone becomes clearer, it is apparent that its pleiotropic actions span both the central nervous system and peripheral organs. Despite a wealth of research, a therapeutic compound specifically targeting the ghrelin system for appetite modulation remains elusive although some promising effects on metabolic function are emerging. This is due to many factors, ranging from the complexity of the ghrelin receptor (Growth Hormone Secretagogue Receptor, GHSR-1a) internalisation and heterodimerization, to biased ligand interactions and compensatory neuroendocrine outputs. Not least is the ubiquitous expression of the GHSR-1a, which makes it impossible to modulate centrallymediated appetite regulation without encroaching on the various peripheral functions attributable to ghrelin. It is becoming clear that ghrelin's central signalling is critical for its effects on appetite, body weight regulation and incentive salience of food. Improving the ability of ghrelin ligands to penetrate the blood brain barrier would enhance central delivery to GHSR-1a expressing brain regions, particularly within the mesolimbic reward circuitry.

  2. Treatment with pioglitazone is associated with decreased preprandial ghrelin levels: a randomized clinical trial.

    Science.gov (United States)

    Taslimi, Shervin; Esteghamati, Alireza; Rashidi, Armin; Tavakkoli, Hosein Moin; Nakhjavani, Manouchehr; Kebriaee-Zadeh, Abbas

    2013-02-01

    The effects of metformin and pioglitazone on ghrelin, a physiologic regulator of appetite and food intake, have not been clearly established. In a randomized clinical trial, we randomly assigned 60 type 2 diabetic patients to either metformin (Group A; n=30) or pioglitazone (Group B; n=30) treatment groups. The groups were similar in their baseline characteristics. A standard fasting 75 g oral glucose tolerance test was performed at time zero before starting metformin or pioglitazone, and 3 months later. After 3 months of treatment, pioglitazone, but not metformin, was significantly associated with weight gain. Both groups experienced a significant reduction in fasting plasma glucose (ppioglitazone group had a significant reduction in preprandial ghrelin levels after treatment (ppioglitazone on ghrelin was independent of changes in body weight, body mass index, glucose control, insulin resistance, and plasma insulin. In conclusion, treatment with pioglitazone is associated with a decrease in preprandial ghrelin levels and therefore, the weight gain and increased food intake related to pioglitazone use cannot be explained by its effects on ghrelin. The effect of pioglitazone on ghrelin is independent of changes in body weight, body mass index, plasma insulin, insulin resistance, or glucose control.

  3. Protective Effect of Ghrelin on Isoniazid-induced Liver Injury in Rat

    Directory of Open Access Journals (Sweden)

    Kheyabany, Shadi Sar Kheyr

    2013-02-01

    Full Text Available Ghrelin (GHR is a peptide that has protective effects on many tissues injury. It has anti-inflammatory and anti-oxidant effects. Isoniazid (INH a widely used antituberculosis drug, has hepatotoxic side effect. The aim of this study was to evaluate the protective role of ghrelin in liver toxicity due to isoniazid. Eighteen male rats were used in this study and divided in to three groups. Including: control, isoniazid, isoniazid and ghrelin groups. Nitric oxide (NO, prostaglandin E2 (PGE2, and hepatic enzymes, ALT (alanine aminotransferase, AST (aspartate aminotransferase, ALK(alkaline phosphatas, were assessed and histologic study of liver were performed as indicators of liver damage following isoniazid toxicity. Ghrelin significantly increased NO metabolites and decreased PGE2 level comparison with INH group, but had no significant change compared to the control group. This study showed that ghrelin administration inhibited liver injury in rats due to isoniazid toxicity. The liver protective role of ghrelin may be mediated at least in part by its anti-inflammatory effect.

  4. Protective Effect of Ghrelin on Sodium Valproate-induced Liver Injury in Rat

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    Sadeghi Niaraki, Mandana

    2013-02-01

    Full Text Available Ghrelin is a peptide that has protective effects on many tissues injury. It has anti-inflammatory and anti-oxidant effects. Sodium valproate is widely used anticonvuisant and anti-depression drug with hepatotoxic side effects. The aim of this study was to evaluated the protective role of ghrelin in liver toxicity due to sodium valproate overdose. Eighteen rats were used in this study and divided in to three groups, containing: control, sodium valproate, and sodium valproate and ghrelin groups. Nitric oxide (NO, prostaglandin E2 (PGE2 and hepatic enzymes AST (aspartate aminotransferase and ALT (alanine aminotransferase, were assessed and histologic study of liver were performed as indicators of liver damage following sodium valproate toxicity. This study showed the ghrelin decreased ALT and AST to the normal level. Our results show that ghrelin significantly increased NO metabolites and decreased PGE2 level comparison with sodium valproate group, but had no significant change compared to the control group. we showed that ghrelin administration inhibited liver injury in rats due to sodium valproate toxicity.

  5. Ghrelin in Female and Male Reproduction

    Directory of Open Access Journals (Sweden)

    Joëlle Dupont

    2010-01-01

    Full Text Available Ghrelin and one of its functional receptors, GHS-R1a (Growth Hormone Secretagogue Receptor 1a, were firstly studied about 15 years. Ghrelin is a multifunctional peptide hormone that affects several biological functions including food intake, glucose release, cell proliferation… Ghrelin and GHS-R1a are expressed in key cells of both male and female reproductive organs in several species including fishes, birds, and mammals suggesting a well-conserved signal through the evolution and a role in the control of fertility. Ghrelin could be a component of the complex series of nutrient sensors such as adipokines, and nuclear receptors, which regulate reproduction in function of the energy stores. The objective of this paper was to report the available information about the ghrelin system and its role at the level of the hypothalamic-pituitary-gonadal axis in both sexes.

  6. Oral administration of recombinant Neisseria meningitidis PorA genetically fused to H. pylori HpaA antigen increases antibody levels in mouse serum, suggesting that PorA behaves as a putative adjuvant.

    Science.gov (United States)

    Vasquez, Abel E; Manzo, Ricardo A; Soto, Daniel A; Barrientos, Magaly J; Maldonado, Aurora E; Mosqueira, Macarena; Avila, Anastasia; Touma, Jorge; Bruce, Elsa; Harris, Paul R; Venegas, Alejandro

    2015-01-01

    The Neisseria meningitidis outer membrane protein PorA from a Chilean strain was purified as a recombinant protein. PorA mixed with AbISCO induced bactericidal antibodies against N. meningitidis in mice. When PorA was fused to the Helicobacter pylori HpaA antigen gene, the specific response against H. pylori protein increased. Splenocytes from PorA-immunized mice were stimulated with PorA, and an increase in the secretion of IL-4 was observed compared with that of IFN-γ. Moreover, in an immunoglobulin sub-typing analysis, a substantially higher IgG1 level was found compared with IgG2a levels, suggesting a Th2-type immune response. This study revealed a peculiar behavior of the purified recombinant PorA protein per se in the absence of AbISCO as an adjuvant. Therefore, the resistance of PorA to proteolytic enzymes, such as those in the gastrointestinal tract, was analyzed, because this is an important feature for an oral protein adjuvant. Finally, we found that PorA fused to the H. pylori HpaA antigen, when expressed in Lactococcus lactis and administered orally, could enhance the antibody response against the HpaA antigen approximately 3 fold. These observations strongly suggest that PorA behaves as an effective oral adjuvant.

  7. Recombinant Helicobacter pylori catalase

    Institute of Scientific and Technical Information of China (English)

    Yang Bai; Ya-Li Zhang; Jian-Feng Jin; Ji-De Wang; Zhao-Shan Zhang

    2003-01-01

    AIM: To construct a recombinant strain which highly expresses catalase of Helicobacter pylori(H.pylori) and assay the activity of H. pylori catalase.METHODS: The catalase DNA was amplified from H. pylori chromosomal DNA with PCR techniques and inserted into the prokaryotie expression vector pET-22b (+), and then was transformed into the BL21 (DE3) E. coli strain which expressed catalase recombinant protein. The activity of H.pylori catalase was assayed by the Beers & Sizers.RESULTS: DNA sequence analysis showed that the sequence of catalase DNA was the same as GenBank's research. The catalase recombinant protein amounted to 24.4 % of the total bacterial protein after induced with IPTG for 3 hours at 37 ℃ and the activity of H. pylori catalase was high in the BL21 (DE3) E. coli strain.CONCLUSION: A clone expressing high activity H. pylori catalase is obtained, laying a good foundation for further studies.

  8. The Levels of Ghrelin, TNF-α, and IL-6 in Children with Cyanotic and Acyanotic Congenital Heart Disease

    Directory of Open Access Journals (Sweden)

    Yasar Dogan

    2007-08-01

    Full Text Available Background/Aim. Ghrelin has effects on nutrient intake and growth. The cause of growth retardation in congenital heart disease is multifactorial. The aim of the present study is to investigate the ghrelin in congenital heart disease and the association of ghrelin with TNF-α and IL-6. Materials and methods. We measured serum ghrelin, TNF-α, and IL-6 levels using spesific immunoassay in 68 patients (47 acyanotic, 21 cyanotic with congenital heart disease and in 25 control subjects. Results. In comparison to controls, serum ghrelin, TNF-α levels were significantly higher in acyanotic patients and cyanotic patients with congenital heart disease (P<.0001. In acyanotic and cyanotic patients with congenital heart disease, there was a positive correlation between ghrelin and TNF-α (r=.485, P<.05 and r=.573 , P<.01, resp.. Conclusion. Serum ghrelin levels is elevated in acyanotic and cyanotic patients with congenital heart disease. Increased ghrelin levels represents malnutrition and growth retardation in these patients. The relation of ghrelin with cytokines may be explained by the possible effect of chronic congestive heart failure and chronic shunt hypoxemia.

  9. Ghrelin in obesity, physiological and pharmacological considerations.

    Science.gov (United States)

    Álvarez-Castro, Paula; Pena, Lara; Cordido, Fernando

    2013-04-01

    The aim of this review is to summarize the physiological and pharmacological aspects of ghrelin. Obesity can be defined as an excess of body fat and is associated with significant disturbances in metabolic and endocrine function. Obesity has become a worldwide epidemic. In obesity there is a decreased growth hormone (GH) secretion, and the altered somatotroph secretion in obesity is functional. Ghrelin is a peptide that has a unique structure with 28 amino-acids and an n-octanoyl ester at its third serine residue, which is essential for its potent stimulatory activity on somatotroph secretion. The pathophysiological mechanism responsible for GH hyposecretion in obesity is probably multifactorial, and there is probably a defect in ghrelin secretion. Ghrelin is the only known circulating orexigenic factor, and has been found to be reduced in obese humans. Ghrelin levels in blood decrease during periods of feeding. Due to its orexigenic and metabolic effects, ghrelin has a potential benefit in antagonizing protein breakdown and weight loss in catabolic conditions such as cancer cachexia, renal and cardiac disease, and age-related frailty. Theoretically ghrelin receptor antagonists could be employed as anti-obesity drugs, blocking the orexigenic signal. By blocking the constitutive receptor activity, inverse agonists of the ghrelin receptor may lower the set-point for hunger, and could be used for the treatment of obesity. In summary, ghrelin secretion is reduced in obesity, and could be partly responsible for GH hyposecretion in obesity, ghrelin antagonist or partial inverse agonists should be considered for the treatment of obesity.

  10. RNAi-mediated Ghrelin affects gastric H(+)-K(+)-ATPase activity and expression of GOAT-Ghrelin system in vitro.

    Science.gov (United States)

    Du, Gai M; Wu, Jie G; Luo, Bi P; Hu, Zhi H; Li, Liu A; Liu, Mao J

    2016-03-01

    Ghrelin has been implicated in the regulation of gastric functional development, and its physiological functions are mediated by Ghrelin-O-acyltransferase (GOAT) which is capable of generating the active form of this polypeptide hormone. However, whether and how ghrelin gene silencing may modify gastric acid secretion and GOAT-Ghrelin system is yet to be explored. The study was performed in gastric mucosal cells from weanling piglets in vitro. We evaluated the effect of ghrelin on gastric acid secretion, gene expression of GOAT and ghrelin as well as ghrelin levels by RNA interference assay. shGhrelin triggered the down-regulation of ghrelin mRNA expression (Pghrelin production and secretion (Pghrelin production and secretion were reduced in gastric mucosal cells and culture medium (Pghrelin gene achieved by RNAi-mediation inhibited the activity of H(+)-K(+)-ATPase and pepsin (PGhrelin gene inhibited the gastric acid secretion with decreased GOAT mRNA and acylated Ghrelin in gastric mucosal cells.

  11. Role of Helicobacter pylori in gastric cancer: Updates

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    Helicobacter pylori (H. pylori ) infection is highly prevalentin human, affecting nearly half of the world'spopulation; however, infection remains asymptomaticin majority of population. During its co-existence withhumans, H. pylori has evolved various strategies tomaintain a mild gastritis and limit the immune responseof host. On the other side, presence of H. pylori is alsoassociated with increased risk for the development ofvarious gastric pathologies including gastric cancer (GC).A complex combination of host genetics, environmentalagents, and bacterial virulence factors are consideredto determine the susceptibility as well as the severityof outcome in a subset of individuals. GC is one of themost common cancers and considered as the third mostcommon cause of cancer related death worldwide. Manystudies had proved H. pylori as an important risk factorin the development of non-cardia GC. Although both H.pylori infection and GC are showing decreasing trendsin the developed world, they still remain a major threatto human population in the developing countries. Thecurrent review attempts to highlight recent progress inthe field of research on H. pylori induced GC and aimsto provide brief insight into H. pylori pathogenesis,the role of major virulence factors of H. pylori thatmodulates the host environment and transform thenormal gastric epithelium to neoplastic one. This reviewalso emphasizes on the mechanistic understanding ofhow colonization and various virulence attributes of H.pylori as well as the host innate and adaptive immuneresponses modulate the diverse signaling pathways thatleads to different disease outcomes including GC.

  12. Helicobacter pylori infection amongst Arab Israeli women with hyperemesis gravidarum—a prospective, controlled study

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    Doron Boltin

    2014-12-01

    Conclusion: H. pylori does not seem to increase the likelihood of hyperemesis gravidarum in Arab Israeli women. However, given the high background prevalence of H. pylori in this population, a larger study is required to corroborate these findings. (MOH20110066

  13. Catechins and Sialic Acid Attenuate Helicobacter pylori-Triggered Epithelial Caspase-1 Activity and Eradicate Helicobacter pylori Infection

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    Jyh-Chin Yang

    2013-01-01

    Full Text Available The inflammasome/caspase-1 signaling pathway in immune cells plays a critical role in bacterial pathogenesis; however, the regulation of this pathway in the gastric epithelium during Helicobacter pylori infection is yet to be elucidated. Here, we investigated the effect of catechins (CAs, sialic acid (SA, or combination of CA and SA (CASA on H. pylori-induced caspase-1-mediated epithelial damage, as well as H. pylori colonization in vitro (AGS cells and in vivo (BALB/c mice. Our results indicate that the activity of caspase-1 and the expression of its downstream substrate IL-1β were upregulated in H. pylori-infected AGS cells. In addition, we observed increased oxidative stress, NADPH oxidase gp91phox, CD68, caspase-1/IL-1β, and apoptosis, but decreased autophagy, in the gastric mucosa of H. pylori-infected mice. We have further demonstrated that treatment with CASA led to synergistic anti-H. pylori activity and was more effective than treatment with CA or SA alone. In particular, treatment with CASA for 10 days eradicated H. pylori infection in up to 95% of H. pylori-infected mice. Taken together, we suggest that the pathogenesis of H. pylori involves a gastric epithelial inflammasome/caspase-1 signaling pathway, and our results show that CASA was able to attenuate this pathway and effectively eradicate H. pylori infection.

  14. Leptin transiently antagonizes ghrelin and long-lastingly orexin in regulation of Ca2+ signaling in neuropeptide Y neurons of the arcuate nucleus

    Institute of Scientific and Technical Information of China (English)

    Daisuke Kohno; Shigetomo Suyama; Toshihiko Yada

    2008-01-01

    AIM: To explore the mechanism for interactions of leptin with ghrelin and orexin in the arcuate nucleus (ARC) activating neuropeptide Y (NPY) neurons during physiological regulation of feeding. METHODS: Single neurons from ARC of adult rats with matured feeding function were isolated. [Ca2+]I was measured to monitore their activities. The time course of leptin effects on ghrelin-induced versus orexin-induced [Ca2+]I increases in NPY neurons was studied. RESULTS: Administration of ghrelin or orexin-A at 10-10 mol/L increased cytosolic Ca2+ concentration ([Ca2+I) in NPY neurons isolated from the ARC of adult rats. Upon administration of leptin at 10-14-1012 mol/L, ghrelin-induced [Ca2+]I increases were initially (<10 min) inhibited but later restored, exhibiting a transient pattern of inhibition. In contrast, orexin-induced [Ca2+]I increases were inhibited by leptin in a long-lasting manner. Furthermore, a prior administration of leptin inhibited orexin action but not ghrelin action to increase [Ca2+]I. CONCLUSION: Leptin counteracted ghrelin effects transiently and orexin effects long-lastingly in NPY neurons. The transient property with which leptin counteracts ghrelin action in NPY neurons may allow the fasting-associated increase in ghrelin levels to activate NPY neurons in the presence of physiological leptin and to stimulate feeding.

  15. Ghrelin: Central and Peripheral Implications in Anorexia Nervosa

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    Méquinion, Mathieu; Langlet, Fanny; Zgheib, Sara; Dickson, Suzanne; Dehouck, Bénédicte; Chauveau, Christophe; Viltart, Odile

    2012-01-01

    Increasing clinical and therapeutic interest in the neurobiology of eating disorders reflects their dramatic impact on health. Chronic food restriction resulting in severe weight loss is a major symptom described in restrictive anorexia nervosa (AN) patients, and they also suffer from metabolic disturbances, infertility, osteopenia, and osteoporosis. Restrictive AN, mostly observed in young women, is the third largest cause of chronic illness in teenagers of industrialized countries. From a neurobiological perspective, AN-linked behaviors can be considered an adaptation that permits the endurance of reduced energy supply, involving central and/or peripheral reprograming. The severe weight loss observed in AN patients is accompanied by significant changes in hormones involved in energy balance, feeding behavior, and bone formation, all of which can be replicated in animals models. Increasing evidence suggests that AN could be an addictive behavior disorder, potentially linking defects in the reward mechanism with suppressed food intake, heightened physical activity, and mood disorder. Surprisingly, the plasma levels of ghrelin, an orexigenic hormone that drives food-motivated behavior, are increased. This increase in plasma ghrelin levels seems paradoxical in light of the restrained eating adopted by AN patients, and may rather result from an adaptation to the disease. The aim of this review is to describe the role played by ghrelin in AN focusing on its central vs. peripheral actions. In AN patients and in rodent AN models, chronic food restriction induces profound alterations in the « ghrelin » signaling that leads to the development of inappropriate behaviors like hyperactivity or addiction to food starvation and therefore a greater depletion in energy reserves. The question of a transient insensitivity to ghrelin and/or a potential metabolic reprograming is discussed in regard of new clinical treatments currently investigated. PMID:23549309

  16. Voluntary exercise attenuates obesity-associated inflammation through ghrelin expressed in macrophages.

    Science.gov (United States)

    Kizaki, Takako; Maegawa, Taketeru; Sakurai, Takuya; Ogasawara, Jun-etsu; Ookawara, Tomomi; Oh-ishi, Shuji; Izawa, Tetsuya; Haga, Shukoh; Ohno, Hideki

    2011-09-30

    Chronic low-level inflammation is associated with obesity and a sedentary lifestyle, causing metabolic disturbances such as insulin resistance. Exercise training has been shown to decrease chronic low-level systemic inflammation in high-fat diet (HFD)-induced obesity. However, the molecular mechanisms mediating its beneficial effects are not fully understood. Ghrelin is a peptide hormone predominantly produced in the stomach that stimulates appetite and induces growth hormone release. In addition to these well-known functions, recent studies suggest that ghrelin localizes to immune cells and exerts an anti-inflammatory effect. The purpose of the current study was to investigate the role of ghrelin expressed in macrophages in the anti-inflammatory effects of voluntary exercise training. Expression of tumor necrosis factor-α (TNF-α), monocyte chemotactic protein (MCP)-1 and F4/80 was increased in adipose tissue from mice fed a HFD (HFD mice) compared with mice fed a standard diet (SD mice), whereas the expression of these inflammatory cytokines was markedly decreased in mice performing voluntary wheel running during the feeding of a HFD (HFEx mice). The expression of TNF-α was also increased in peritoneal macrophages by a HFD and exercise training inhibited the increase of TNF-α expression. Interestingly, expression of ghrelin in peritoneal macrophages was decreased by a HFD and recovered by exercise training. Suppression of ghrelin expression by siRNA increased TNF-α expression and LPS-stimulated NF-κB activation in RAW264 cells, which is a macrophage cell line. TNF-α expression by stimulation with LPS was significantly suppressed in RAW264 cells cultured in the presence of ghrelin. These results suggest that ghrelin exerts potent anti-inflammatory effects in macrophages and functions as a mediator of the beneficial effects of exercise training. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Effectiveness of Citrus Fruits on Helicobacter pylori

    Science.gov (United States)

    2017-01-01

    It is known that Helicobacter pylori infection is associated with chronic gastritis, peptic ulcer, and gastric carcinoma. Due to the increased side effects of the treatment regimens and the development of antimicrobial resistance, a number of natural compounds have been tested as potential alternatives. In this review, we will examine the current knowledge on the effect of Citrus fruits and their derivatives against H. pylori, highlighting the remaining outstanding questions on the development of novel therapeutic strategies. PMID:28408943

  18. [Leptin, ghrelin, and physical exercise].

    Science.gov (United States)

    da Mota, Gustavo R; Zanesco, Angelina

    2007-02-01

    Obesity is a major public health problem in the Western world resulting in serious social, physical and psychological damages. The genesis of obesity is complex involving a variety of factors such as genetic, psychological, metabolic and environmental factors. Progress in endocrinology and metabolism show that adipocyte is considered now as an endocrine tissue producing several substance including adiponectin, tumor necrosis factor-alpha, interleukin-6 and leptin. Specifically, leptin is the main peptide produced by the adipocyte and its serum concentration represents an important peripheral signal in the regulation of food intake and energy expenditure in mammals. In addition to leptin, a new peptide was discovered recently named ghrelin. Ghrelin, a peptide hormone identified in the stomach, is directly involved with the regulation of energy balance and obesity. Physical exercise has been used as a non-pharmacological tool in management of body weight and the effect of physical activity on weight control is an important issue for clinical studies in endocrinology field. Thus, this review will attempt to update the knowledge of leptin and ghrelin on the body weight regulation and the effect of exercise training on these peptide concentrations. It can be concluded that the relationship between physical exercise and the plasma concentration of these peptides is not clear. The reasons for that could be related to the differences in duration, intensity and frequency of the training program employed in each study. Indeed, most of the studies have not analyzed the intensity of training program by either plasma lactate concentration or maximum oxygen consumption. On the other hand, genetic basis could also explain the discrepancies found in some studies, since it has been shown that polymorphism for a variety of genes might be an important factor to determine the differences of cellular response to physical training.

  19. [Maternal infection due to Helicobacter pylori does not increase the risk of the infection in the first trimester of the life of their infants].

    Science.gov (United States)

    Troncoso, Paula; Villagrán, Andrea; Vera, Macarena; Estay, Alberto; Ortiz, Marlene; Serrano, Carolina; Hernández, Caroll; Harris, Paul R

    H. pylori infection is acquired early in childhood. However, there is little information available regarding the role of breastfeeding and neonatal acquisition of the infection. To evaluate factors affecting the acquisition of H. pylori in newborns and infants from infected mothers. Consecutive mothers and their newborns were recruited into the study from the maternity unit, immediately after delivery. After signing informed consent, one stool sample from the mother was obtained before hospital discharge. Three stool samples of the newborns were then collected at home at 15, 60, and 90 days of life, for the detection of H. pylori antigen (Monoclonal HpSAg, sensitivity 94% and specificity 97%). The socio-epidemiological and biomedical variables were also analysed using a questionnaire. A total of 32 mother-child pairs (64 subjects) were enrolled. The mean maternal age was 30.1±5.1 years, with 53% vaginal delivery, and 85% exclusively breastfed. There were 13 (40%) infected mothers. No H. pylori infection was detected in newborns and infants up to 3 months of follow-up. No significant differences were found in socioeconomic level between infected versus non-infected mothers (both groups mostly in the very high socioeconomic category: 28% and 32%, respectively, P=.15) and in the number of family members between infected versus non-infected mothers (3.8±0.8 vs 4.2±1.8 persons, P=.18). Despite having a significant percentage of H. pylori-infected mothers, no newborn was infected at the third month of life. The protective role of breastfeeding cannot be ruled out. Copyright © 2016 Sociedad Chilena de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Ghrelin receptor regulates adipose tissue inflammation in aging.

    Science.gov (United States)

    Lin, Ligen; Lee, Jong Han; Buras, Eric D; Yu, Kaijiang; Wang, Ruitao; Smith, C Wayne; Wu, Huaizhu; Sheikh-Hamad, David; Sun, Yuxiang

    2016-01-01

    Aging is commonly associated with low-grade adipose inflammation, which is closely linked to insulin resistance. Ghrelin is the only circulating orexigenic hormone which is known to increase obesity and insulin resistance. We previously reported that the expression of the ghrelin receptor, growth hormone secretagogue receptor (GHS-R), increases in adipose tissues during aging, and old Ghsr(-/-) mice exhibit a lean and insulin-sensitive phenotype. Macrophages are major mediators of adipose tissue inflammation, which consist of pro-inflammatory M1 and anti-inflammatory M2 subtypes. Here, we show that in aged mice, GHS-R ablation promotes macrophage phenotypical shift toward anti-inflammatory M2. Old Ghsrp(-/-) mice have reduced macrophage infiltration, M1/M2 ratio, and pro-inflammatory cytokine expression in white and brown adipose tissues. We also found that peritoneal macrophages of old Ghsrp(-/-) mice produce higher norepinephrine, which is in line with increased alternatively-activated M2 macrophages. Our data further reveal that GHS-R has cell-autonomous effects in macrophages, and GHS-R antagonist suppresses lipopolysaccharide (LPS)-induced inflammatory responses in macrophages. Collectively, our studies demonstrate that ghrelin signaling has an important role in macrophage polarization and adipose tissue inflammation during aging. GHS-R antagonists may serve as a novel and effective therapeutic option for age-associated adipose tissue inflammation and insulin resistance.

  1. Ghrelin en la Amenorrea Hipotalámica Funcional relacionada con la desnutrición Ghrelin in Functional Hypothalamic Amenorrohea related with undernourished

    Directory of Open Access Journals (Sweden)

    León Fiszlejder

    2010-04-01

    encuentra acentuada en estas pacientes. La correlación negativa entre la insulina y el Ghrelin probablemente es mediada por el sistema vagal, como lo sugiere el aumento del polipéptido pancreático, un marcador confiable de la actividad vagal. Adicionalmente, el hipercortisolismo de estas pacientes y posiblemente la somatostatina a través de sus receptores en el páncreas, podrían regular en forma negativa la actividad de los receptores de insulina, con el consiguiente incremento del Ghrelin. Conclusión: el ascenso del Ghrelin en la AHF y sus particulares interrelaciones con la insulina y el eje adrenal convergen para mantener el equilibrio homeostático, intentando facilitar así el aporte de metabolitos energéticos a estas pacientes desnutridas, frecuentemente osteosporóticas, inmunodeprimidas y con un alto riesgo cardiovascular.Functional Hypothalamic Amenorrhoea (FHA reflects a homeostatic adaptive process resulting from a negative energy balance (increased caloric output/expenditure with inadequate nutrient replenishment. Hypothalamic hormones and peripheral neuropeptides from the fat tissue (leptin, adiponectin and other adipokines, the upper gastrointestinal tract (Ghrelin and pancreas (insulin are involved in this syndrome. This "peripheral circuit” is functionally interrelated with the central hypothalamic circuit controlling appetite and satiety. The decrease in leptin, an anorexigenic signal, potentiates the orexigenic effect of Ghrelin (the basal levels of Ghrelin are elevated in FHA and induces an increased CRH activity within the hypothalamus. This hormone, in turn, inhibits pulsatile GnRH secretion. Besides its potent GH secretagogue activity, Ghrelin is a peptide that influences insulin secretion and affects the metabolism of carbohydrates and lipids. Usually, a preprandial increase in Ghrelin levels is observed, followed by a postprandial decrease related to satiety. In obese subjects, this decrease is less marked and slower. Conversely, in

  2. The ghrelin signalling system is involved in the consumption of sweets.

    Directory of Open Access Journals (Sweden)

    Sara Landgren

    Full Text Available The gastric-derived orexigenic peptide ghrelin affects brain circuits involved in energy balance as well as in reward. Indeed, ghrelin activates an important reward circuit involved in natural- as well as drug-induced reward, the cholinergic-dopaminergic reward link. It has been hypothesized that there is a common reward mechanism for alcohol and sweet substances in both animals and humans. Alcohol dependent individuals have higher craving for sweets than do healthy controls and the hedonic response to sweet taste may, at least in part, depend on genetic factors. Rat selectively bred for high sucrose intake have higher alcohol consumption than non-sucrose preferring rats and vice versa. In the present study a group of alcohol-consuming individuals selected from a population cohort was investigated for genetic variants of the ghrelin signalling system in relation to both their alcohol and sucrose consumption. Moreover, the effects of GHS-R1A antagonism on voluntary sucrose-intake and operant self-administration, as well as saccharin intake were investigated in preclinical studies using rodents. The effects of peripheral grelin administration on sucrose intake were also examined. Here we found associations with the ghrelin gene haplotypes and increased sucrose consumption, and a trend for the same association was seen in the high alcohol consumers. The preclinical data show that a GHS-R1A antagonist reduces the intake and self-administration of sucrose in rats as well as saccharin intake in mice. Further, ghrelin increases the intake of sucrose in rats. Collectively, our data provide a clear indication that the GHS-R1A antagonists reduces and ghrelin increases the intake of rewarding substances and hence, the central ghrelin signalling system provides a novel target for the development of drug strategies to treat addictive behaviours.

  3. Ghrelin ameliorates the human alveolar epithelial A549 cell apoptosis induced by lipopolysaccharide

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    Huang, Chunrong; Zheng, Haichong; He, Wanmei; Lu, Guifang; Li, Xia [Department of Medical Intensive Care Unit, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080 (China); Deng, Yubin, E-mail: dengyub@mail.sysu.edu.cn [Research Center of Translational Medicine, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080 (China); Zeng, Mian, E-mail: zengmian2004@163.com [Department of Medical Intensive Care Unit, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080 (China)

    2016-05-20

    Ghrelin is a gastric acyl-peptide that plays an inhibitory role in cell apoptosis. Herein we investigate the protective effects of ghrelin in LPS-induced apoptosis of human alveolar epithelial A549 cells, along with the possible molecular mechanisms. LPS exposure impaired cell viability and increased apoptosis of A549 cells significantly in concentration- and time-dependent manners embodied in increased Bax and cleaved caspase-3 production, coupled with decreased Bcl-2 levels. Simultaneously, LPS remarkably decreased the expression of phosphatidylinositol 3 kinase/protein kinase B (PI3K/Akt) and extracellular signal-regulated kinas (ERK) in A549 cells. However, ghrelin'pretreatment ameliorated LPS-caused alterations in the ratio of Bax/Bcl-2 and cleaved caspase-3 expression, whereas activated the PI3K/Akt and ERK signaling. These results demonstrate that ghrelin lightens LPS-induced apoptosis of human alveolar epithelial cells partly through activating the PI3K/Akt and ERK pathway and thereby might benefit alleviating septic ALI. -- Graphical abstract: Ghrelin ameliorates the human alveolar epithelial A549 cells apoptosis induced by lipopolysaccharide partly through activating the PI3K/Akt and ERK pathway. Display Omitted -- Highlights: •It has been observed that LPS insult significantly increased apoptosis in A549 cells. •Both Akt and ERK signaling are critical adapter molecules to mediate the ghrelin-mediated proliferative effect. •Ghrelin may have a therapeutic effect in the prevention of LPS-induced apoptosis.

  4. Helicobacter pylori and Gastrointestinal Malignancies.

    Science.gov (United States)

    Venerito, Marino; Vasapolli, Riccardo; Rokkas, Theodoros; Malfertheiner, Peter

    2015-09-01

    Helicobacter pylori infection is the principal trigger of gastric carcinogenesis and gastric cancer (GC) and remains the third leading cause of cancer-related death in both sexes worldwide. In a big Japanese study, the risk of developing GC in patients with peptic ulcer disease who received H. pylori eradication therapy and annual endoscopic surveillance for a mean of 9.9 years was significantly lower after successful eradication therapy compared to the group with persistent infection (0.21%/year and 0.45%/year, respectively, p = .049). According to a recent meta-analysis, H. pylori eradication is insufficient in GC risk reduction in subjects with advanced precancerous conditions (i.e., intestinal metaplasia and dysplasia). A microsimulation model suggested screening smokers over the age of 50 in the U.S. for serum pepsinogens. This would allow to detect advanced gastric atrophy with endoscopic follow-up of subjects testing positive as a cost-effective strategy to reduce GC mortality. In a Taiwanese study, the anti-H. pylori IgG-based test-and-treat program had lower incremental cost-effectiveness ratios than that with (13)C-urea breath test in both sexes to prevent GC whereas expected years of life lost for GC were higher and the incremental cost-effectiveness ratios of test-and-treat programs were more cost-effective in young adults (30-69 years old) than in elders (>70 years old). With respect to gastrointestinal malignancies other than GC, a meta-analysis confirmed the inverse association between H. pylori infection and esophageal adenocarcinoma. In a Finnish study, H. pylori seropositivity was associated with an increased risk of biliary tract cancers (multivariate adjusted OR 2.63; 95% CI: 1.08-6.37), another meta-analysis showed a slightly increased rate of pancreatic cancer in patients with CagA-negative strains (OR: 1.30; 95% CI: 1.02-1.65), whereas current data suggest that the association between H. pylori and colorectal neoplasms may be population

  5. Elevated ghrelin predicts food intake during experimental sleep restriction.

    Science.gov (United States)

    Broussard, Josiane L; Kilkus, Jennifer M; Delebecque, Fanny; Abraham, Varghese; Day, Andrew; Whitmore, Harry R; Tasali, Esra

    2016-01-01

    Sleep curtailment has been linked to obesity, but underlying mechanisms remain to be elucidated. This study assessed whether sleep restriction alters 24-h profiles of appetite-regulating hormones ghrelin, leptin, and pancreatic polypeptide during a standardized diet and whether these hormonal alterations predict food intake during ad libitum feeding. Nineteen healthy, lean men were studied under normal sleep and sleep restriction in a randomized crossover design. Blood samples were collected for 24 h during standardized meals. Subsequently, participants had an ad libitum feeding opportunity (buffet meals and snacks) and caloric intake was measured. Ghrelin levels were increased after sleep restriction as compared with normal sleep (P food intake and the development of obesity. © 2015 The Obesity Society.

  6. [Relationship between Helicobacter pylori status and the development of reflux esophagitis or Barrett's esophagus].

    Science.gov (United States)

    Watari, Jiro; Tomita, Toshihiko; Oshima, Tadayuki; Fukui, Hirokazu; Miwa, Hiroto

    2013-08-01

    To date, there are many studies on the association between Helicobacter pylori (H. pylori) infection and gastroesophageal reflux disease. Here we reviewed the relationship between H. pylori status and the development of reflux esophagitis (RE) or Barrett's esophagus (BE). According to many case-controlled studies, H. pylori infection may play a protective role in the development of RE. However, the frequency of RE development does not increase following successful H. pylori treatment based on the previous studies including meta-analysis and systematic review. Even though RE newly develops after H. pylori eradication, endoscopic findings reveal mild such as grade A or B according to the Los Angeles Classification System. With regard to BE, there is an inverse significant relationship. Since there are few studies indicating that BE increases after treatment of H. pylori, the eradication should be recommended for patients with H. pylori infection irrespective of the presence of RE or BE even in terms of the prevention of gastric cancer.

  7. Acylated and desacyl ghrelin are associated with hepatic lipogenesis, β-oxidation and autophagy: role in NAFLD amelioration after sleeve gastrectomy in obese rats.

    Science.gov (United States)

    Ezquerro, Silvia; Méndez-Giménez, Leire; Becerril, Sara; Moncada, Rafael; Valentí, Víctor; Catalán, Victoria; Gómez-Ambrosi, Javier; Frühbeck, Gema; Rodríguez, Amaia

    2016-12-23

    Bariatric surgery improves non-alcoholic fatty liver disease (NAFLD). Our aim was to investigate the potential role of ghrelin isoforms in the resolution of hepatic steatosis after sleeve gastrectomy, a restrictive bariatric surgery procedure, in diet-induced obese rats. Male Wistar rats (n = 161) were subjected to surgical (sham operation and sleeve gastrectomy) or dietary interventions [fed ad libitum a normal (ND) or a high-fat (HFD) diet or pair-fed]. Obese rats developed hepatosteatosis and showed decreased circulating desacyl ghrelin without changes in acylated ghrelin. Sleeve gastrectomy induced a dramatic decrease of desacyl ghrelin, but increased the acylated/desacyl ghrelin ratio. Moreover, sleeve gastrectomy reduced hepatic triglyceride content and lipogenic enzymes Mogat2 and Dgat1, increased mitochondrial DNA amount and induced AMPK-activated mitochondrial FFA β-oxidation and autophagy to a higher extent than caloric restriction. In primary rat hepatocytes, the incubation with both acylated and desacyl ghrelin (10, 100 and 1,000 pmol/L) significantly increased TG content, triggered AMPK-activated mitochondrial FFA β-oxidation and autophagy. Our data suggest that the decrease in the most abundant isoform, desacyl ghrelin, after sleeve gastrectomy contributes to the reduction of lipogenesis, whereas the increased relative acylated ghrelin levels activate factors involved in mitochondrial FFA β-oxidation and autophagy in obese rats, thereby ameliorating NAFLD.

  8. Acylated and desacyl ghrelin are associated with hepatic lipogenesis, β-oxidation and autophagy: role in NAFLD amelioration after sleeve gastrectomy in obese rats

    Science.gov (United States)

    Ezquerro, Silvia; Méndez-Giménez, Leire; Becerril, Sara; Moncada, Rafael; Valentí, Víctor; Catalán, Victoria; Gómez-Ambrosi, Javier; Frühbeck, Gema; Rodríguez, Amaia

    2016-01-01

    Bariatric surgery improves non-alcoholic fatty liver disease (NAFLD). Our aim was to investigate the potential role of ghrelin isoforms in the resolution of hepatic steatosis after sleeve gastrectomy, a restrictive bariatric surgery procedure, in diet-induced obese rats. Male Wistar rats (n = 161) were subjected to surgical (sham operation and sleeve gastrectomy) or dietary interventions [fed ad libitum a normal (ND) or a high-fat (HFD) diet or pair-fed]. Obese rats developed hepatosteatosis and showed decreased circulating desacyl ghrelin without changes in acylated ghrelin. Sleeve gastrectomy induced a dramatic decrease of desacyl ghrelin, but increased the acylated/desacyl ghrelin ratio. Moreover, sleeve gastrectomy reduced hepatic triglyceride content and lipogenic enzymes Mogat2 and Dgat1, increased mitochondrial DNA amount and induced AMPK-activated mitochondrial FFA β-oxidation and autophagy to a higher extent than caloric restriction. In primary rat hepatocytes, the incubation with both acylated and desacyl ghrelin (10, 100 and 1,000 pmol/L) significantly increased TG content, triggered AMPK-activated mitochondrial FFA β-oxidation and autophagy. Our data suggest that the decrease in the most abundant isoform, desacyl ghrelin, after sleeve gastrectomy contributes to the reduction of lipogenesis, whereas the increased relative acylated ghrelin levels activate factors involved in mitochondrial FFA β-oxidation and autophagy in obese rats, thereby ameliorating NAFLD. PMID:28008992

  9. Progress on Ghrelin in Poultry%禽类 Ghrelin 研究进展

    Institute of Scientific and Technical Information of China (English)

    陈文明; 何敏; 杨欢

    2015-01-01

    The peptide hormone ghrelin is secreted mainly by stomach,and is the only ligand that was found for growth hormone releasing hormone receptor to date.There are two forms of ghrelins exist in the body:N-octanoyl-modified ghrelin and des-acyl ghrelin,and this modification is essential for the activity of ghrelin.Ghrelin is widely distributed in various tissues in the body,with a variety of biological functions:regulating the release of growth hormone,food intaking,energy balance and so on.At present there are many reports related to the rodent animal ghrelin and the corresponding researches have been successful, but the study on poultry ghrelin lags behind,there are many aspects of poultry ghrelin to make clear.This paper made a simple summarize on the research of the poultry ghrelin about the molecular structure,tissue distribution and biological functions,hoping to provide reference for the study of ghrelin in poultry.%Ghrelin主要是由胃分泌的一种肽类激素,是迄今发现的生长激素促分泌素受体的唯一内源性配体。其在体内具有 N-端辛酰基化和 N-端去辛酰基化两种存在形式,N-末端辛酰基化对保证其生物活性是必需的。Ghrelin 广泛分布于机体各种组织中,具有调节生长激素释放、摄食和能量平衡等多种生物学功能。目前关于啮齿类动物 Ghrelin 的相关报道较多,研究已比较透彻,而对于禽类 Ghrelin 的研究则相对滞后,还有许多值得一步研究的地方。论文就近年来关于禽类 Ghrelin 的分子结构、组织分布、生物功能的研究做一概述,以期为禽类 Ghrelin 的研究提供参考。

  10. Impact of sustained weight loss achieved through Roux-en-Y gastric bypass or a lifestyle intervention on ghrelin, obestatin, and ghrelin/obestatin ratio in morbidly obese patients.

    Science.gov (United States)

    Martins, Catia; Kjelstrup, Louise; Mostad, Ingrid L; Kulseng, Bård

    2011-06-01

    Appetite-regulating hormones seem to play an important role in weight loss after bariatric surgery. Less is known regarding long-term weight loss maintenance. The objective of the study was to evaluate ghrelin and obestatin levels following long-term weight loss achieved through bariatric surgery or a lifestyle intervention in morbidly obese patients. The study was cross-sectional in design carried out in a university research center setting. The participants were weight-stable morbidly obese patients who had undergone, on average, 3 years ago, Roux-en-Y gastric bypass (RYGB) surgery (n=9) or a lifestyle weight loss intervention (n=8), and patients on a waiting list for bariatric surgery (control group; n=9). The main outcome measures were fasting/postprandial plasma levels of total ghrelin and obestatin and ghrelin/obestatin ratio. Fasting ghrelin and obestatin plasma levels were significantly elevated in the RYGB, but not in the lifestyle group, as compared with the control group. There was no statistical significant difference in fasting ghrelin/obestatin ratio among study groups. Ghrelin levels were suppressed after breakfast in all groups, with no significant differences in postprandial levels overtime between them. Obestatin levels did not change postprandially in any of the groups, but the area under the curve was significantly higher in the RYGB than in the control group. Sustained weight loss maintenance seems to be associated with increased fasting levels of ghrelin and obestatin after RYGB surgery, but not after a lifestyle intervention, while maintaining ghrelin/obestatin ratio. Ghrelin is, therefore, unlikely to contribute to weight loss maintenance after RYGB, and other mechanisms are probably involved.

  11. The ghrelin receptor agonist HM01 mimics the neuronal effects of ghrelin in the arcuate nucleus and attenuates anorexia-cachexia syndrome in tumor-bearing rats.

    Science.gov (United States)

    Borner, Tito; Loi, Laura; Pietra, Claudio; Giuliano, Claudio; Lutz, Thomas A; Riediger, Thomas

    2016-07-01

    The gastric hormone ghrelin positively affects energy balance by increasing food intake and reducing energy expenditure. Ghrelin mimetics are a possible treatment against cancer anorexia-cachexia syndrome (CACS). This study aimed to characterize the action of the nonpeptidergic ghrelin receptor agonist HM01 on neuronal function, energy homeostasis and muscle mass in healthy rats and to evaluate its possible usefulness for the treatment of CACS in a rat tumor model. Using extracellular single-unit recordings, we tested whether HM01 mimics the effects of ghrelin on neuronal activity in the arcuate nucleus (Arc). Furthermore, we assessed the effect of chronic HM01 treatment on food intake (FI), body weight (BW), lean and fat volumes, and muscle mass in healthy rats. Using a hepatoma model, we investigated the possible beneficial effects of HM01 on tumor-induced anorexia, BW loss, muscle wasting, and metabolic rate. HM01 (10(-7)-10(-6) M) mimicked the effect of ghrelin (10(-8) M) by increasing the firing rate in 76% of Arc neurons. HM01 delivered chronically for 12 days via osmotic minipumps (50 μg/h) increased FI in healthy rats by 24%, paralleled by increased BW, higher fat and lean volumes, and higher muscle mass. Tumor-bearing rats treated with HM01 had 30% higher FI than tumor-bearing controls and were protected against BW loss. HM01 treatment resulted in higher muscle mass and fat mass. Moreover, tumor-bearing rats reduced their metabolic rate following HM01 treatment. Our studies substantiate the possible therapeutic usefulness of ghrelin receptor agonists like HM01 for the treatment of CACS and possibly other forms of disease-related anorexia and cachexia.

  12. Potentiation of ghrelin signaling attenuates cancer anorexia-cachexia and prolongs survival.

    Science.gov (United States)

    Fujitsuka, N; Asakawa, A; Uezono, Y; Minami, K; Yamaguchi, T; Niijima, A; Yada, T; Maejima, Y; Sedbazar, U; Sakai, T; Hattori, T; Kase, Y; Inui, A

    2011-07-26

    Cancer anorexia-cachexia syndrome is characterized by decreased food intake, weight loss, muscle tissue wasting and psychological distress, and this syndrome is a major source of increased morbidity and mortality in cancer patients. This study aimed to clarify the gut-brain peptides involved in the pathogenesis of the syndrome and determine effective treatment for cancer anorexia-cachexia. We show that both ghrelin insufficiency and resistance were observed in tumor-bearing rats. Corticotropin-releasing factor (CRF) decreased the plasma level of acyl ghrelin, and its receptor antagonist, α-helical CRF, increased food intake of these rats. The serotonin 2c receptor (5-HT2cR) antagonist SB242084 decreased hypothalamic CRF level and improved anorexia, gastrointestinal (GI) dysmotility and body weight loss. The ghrelin receptor antagonist (D-Lys3)-GHRP-6 worsened anorexia and hastened death in tumor-bearing rats. Ghrelin attenuated anorexia-cachexia in the short term, but failed to prolong survival, as did SB242084 administration. In addition, the herbal medicine rikkunshito improved anorexia, GI dysmotility, muscle wasting, and anxiety-related behavior and prolonged survival in animals and patients with cancer. The appetite-stimulating effect of rikkunshito was blocked by (D-Lys3)-GHRP-6. Active components of rikkunshito, hesperidin and atractylodin, potentiated ghrelin secretion and receptor signaling, respectively, and atractylodin prolonged survival in tumor-bearing rats. Our study demonstrates that the integrated mechanism underlying cancer anorexia-cachexia involves lowered ghrelin signaling due to excessive hypothalamic interactions of 5-HT with CRF through the 5-HT2cR. Potentiation of ghrelin receptor signaling may be an attractive treatment for anorexia, muscle wasting and prolong survival in patients with cancer anorexia-cachexia.

  13. Potentiation of ghrelin signaling attenuates cancer anorexia–cachexia and prolongs survival

    Science.gov (United States)

    Fujitsuka, N; Asakawa, A; Uezono, Y; Minami, K; Yamaguchi, T; Niijima, A; Yada, T; Maejima, Y; Sedbazar, U; Sakai, T; Hattori, T; Kase, Y; Inui, A

    2011-01-01

    Cancer anorexia–cachexia syndrome is characterized by decreased food intake, weight loss, muscle tissue wasting and psychological distress, and this syndrome is a major source of increased morbidity and mortality in cancer patients. This study aimed to clarify the gut–brain peptides involved in the pathogenesis of the syndrome and determine effective treatment for cancer anorexia–cachexia. We show that both ghrelin insufficiency and resistance were observed in tumor-bearing rats. Corticotropin-releasing factor (CRF) decreased the plasma level of acyl ghrelin, and its receptor antagonist, α-helical CRF, increased food intake of these rats. The serotonin 2c receptor (5-HT2cR) antagonist SB242084 decreased hypothalamic CRF level and improved anorexia, gastrointestinal (GI) dysmotility and body weight loss. The ghrelin receptor antagonist (D-Lys3)-GHRP-6 worsened anorexia and hastened death in tumor-bearing rats. Ghrelin attenuated anorexia–cachexia in the short term, but failed to prolong survival, as did SB242084 administration. In addition, the herbal medicine rikkunshito improved anorexia, GI dysmotility, muscle wasting, and anxiety-related behavior and prolonged survival in animals and patients with cancer. The appetite-stimulating effect of rikkunshito was blocked by (D-Lys3)-GHRP-6. Active components of rikkunshito, hesperidin and atractylodin, potentiated ghrelin secretion and receptor signaling, respectively, and atractylodin prolonged survival in tumor-bearing rats. Our study demonstrates that the integrated mechanism underlying cancer anorexia–cachexia involves lowered ghrelin signaling due to excessive hypothalamic interactions of 5-HT with CRF through the 5-HT2cR. Potentiation of ghrelin receptor signaling may be an attractive treatment for anorexia, muscle wasting and prolong survival in patients with cancer anorexia–cachexia. PMID:22832525

  14. [Helicobacter pylori -- 2014].

    Science.gov (United States)

    Buzás, György Miklós

    2015-02-08

    The author reviews the main achievements in Helicobacter pylori research in the past 2 years. Of the more than 1000 microRNAs described thus far, sets of over- and underexpressed samples were identified that are associated with either gastric cancer or precancerous lesions, and some of them could be either markers or therapeutic targets in the near future. Meta-analyses involved 95 new publications: the association between infection and oesophageal, colorectal, pancreatic and liver carcinomas is supported by the increased odds ratios, but the results do not reach the strength seen in gastric carcinoma. Epstein-Barr virus is an emerging pathogen: 10% of gastric cancers are virus-associated; the prevalence of the virus in normal mucosa, chronic gastritis and peptic ulcer are currently being studied. Current Helicobacter pylori eradication regimens frequently achieve suboptimal results: a few optimisation methods are presented, although not all are supported by the meta-analyses. In 2013, the European Helicobacter Study Group proposed the development of a pan-European registry; data from 5792 patients registered so far indicated that many therapeutic regimens resulted in a low eradication rate. In 2013, the Healthy Stomach Initiative was started with the aim of supporting and disseminating research performed in the field of healthy and diseased stomachs.

  15. Proghrelin peptides: Desacyl ghrelin is a powerful inhibitor of acylated ghrelin, likely to impair physiological effects of acyl ghrelin but not of obestatin A study of pancreatic polypeptide secretion from mouse islets

    DEFF Research Database (Denmark)

    Kumar, Rajesh; Salehi, Albert; Rehfeld, Jens F;

    2010-01-01

    Proghrelin, produced by the ghrelin (A-like) cells of the gastric mucosa, gives rise to cleavage products, including desacyl ghrelin, acyl ghrelin and obestatin. The products are thought to be secreted concomitantly. In an earlier study we found acyl ghrelin and obestatin, but not desacyl ghrelin...

  16. Helicobacter pylori damages human gallbladder epithelial cells in vitro

    Institute of Scientific and Technical Information of China (English)

    Dong-Feng Chen; Lu Hu; Ping Yi; Wei-Wen Liu; Dian-Chun Fang; Hong Cao

    2008-01-01

    AIM: To study the mechanism by which Helicobacter pylori (Hpy/orO damages human gallbladder epithelial cells (HGBEC).METHODS: H pylori isolated from gallbladder were cultured in a liquid medium. Different concentration supernatants and sonicated extracts of H pylori cells were then added to HGBEC in a primary culture. The morphological changes in HGBEC as well as changes in the levels of alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and glutamyltransferase (GGT)were measured.RESULTS: According to the culture curve of HGBEC,it was convenient to study the changes in HGBEC by adding H pylori sonicated extracts and H pylori culture supernatants. Both H pylori sonicated extracts and H pylori culture supernatants had a significant influence on HGBEC morphology, i.e. HGBEC grew more slowly, their viability decreased and their detachment increased. Furthermore, HGBEC ruptured and died. The levels of ALP (33.84 ± 6.00 vs 27.01± 4.67, P < 0.05), LDH (168.37 ± 20.84 vs 55.51 ±17.17, P < 0.01) and GGT (42.01 ± 6.18 vs 25.34 ±4.33, P < 0.01) significantly increased in the HGBEC culture supernatant in a time- and concentrationdependent. The damage to HGBEC in Hpylori culture liquid was more significant than that in H pylori sonicated extracts.CONCLUSION: H pylori induces no obvious damage to HGBEC.

  17. Design and characterization of a fluorescent ghrelin analog for imaging the growth hormone secretagogue receptor 1a.

    Science.gov (United States)

    McGirr, Rebecca; McFarland, Mark S; McTavish, Jillian; Luyt, Leonard G; Dhanvantari, Savita

    2011-12-10

    Ghrelin is a 28-amino acid peptide hormone produced in the stomach. It binds to the growth hormone secretagogue receptor 1a (GHS-R1a), a class A G-protein-coupled receptor. In the present study, we describe the design, synthesis and characterization of a truncated, 18-amino acid analog of ghrelin conjugated to a fluorescent molecule, fluorocein isothiocyanate (FITC), through the addition of a lysine at its C terminus ([Dpr(octanoyl)(3), Lys(fluorescein)(19)]ghrelin(1-19)). Receptor binding affinity of this novel fluorescein-ghrelin(1-18) was similar to that of wild-type ghrelin and a synthetic GHS-R1a ligand, hexarelin. Live cell imaging in CHO/GHS-R1a cells demonstrated cell surface receptor labeling and internalization, and agonist activity of fluorescein-ghrelin(1-18) was confirmed by increased phosphorylation of ERK1/2. We also show that GHS-R1a protein is expressed primarily in the heart when compared to all other organs, suggesting high receptor density in the left ventricle. Finally, we demonstrate that fluorescein-ghrelin(1-18) binds specifically to heart tissue in situ, and its binding is displaced by both wt ghrelin and hexarelin. We have therefore developed a novel imaging probe, fluorescein-ghrelin(1-18), that can be used to image GHS-R1a in situ, for the purposes of investigating mechanisms of receptor trafficking or pharmacological agents that target GHS-R1a.

  18. Role of the duodenum in regulation of plasma ghrelin levels and body mass index after subtotal gastrectomy

    Institute of Scientific and Technical Information of China (English)

    Hai-Tao Wang; Qi-Cheng Lu; Qing Wang; Rong-Chao Wang; Yun Zhang; Hai-Long Chen; Hong Zhao; Hai-Xin Qian

    2008-01-01

    AIM: To investigate the role of the duodenum in the regulation of plasma ghrelin levels and body mass index (BMI), and the correlation between them after subtotal gastrectomy.METHODS: Forty-two patients with To-1No-1M0 gastric cancer were divided into two groups after gastrectomy according to digestive reconstruction pattern,Billroth I group (n = 23) and Billroth Ⅱ group (n = 19).Ghrelin levels were determined with radioimmunoassay (RIA) before and on d 1, 7, 30 and 360 after gastrectomy,and BMI was also measured.RESULTS: The two groups had identical postoperative trends in ghrelin alterations during the early stage, both decreasing sharply to a nadir on d 1 (36.7% vs 35.7%),then markedly increasing on d 7 (51.0% vs 51.1%). On d 30, ghrelin levels in the Billroth I group were slightly higher than those in the Billroth Ⅱ group. However,those of the Billroth I group recovered to 93.6% on d 360, which approached, although lower than, the preoperative levels, and no statistically significant difference was observed. Those of the Billroth Ⅱ group recovered to only 81.6% and manifested significant discrepancy with preoperative levels (P = 0.033).Compared with preoperative levels, ghrelin levels of the two groups decreased by 6.9% and 18.4% and BMI fell by 3.3% and 6.4%, respectively. The linear regression correlations were revealed in both groups between decrease of ghrelin level and BMI (R12 = 0.297, P = 0.007;R22 = 0.559, P < 0.001).CONCLUSION: Anatomically and physiologically, the duodenum compensatively promotes ghrelin recovery and accordingly enhances BMI after gastrectomy.Regarding patients with insufficient ghrelin secretion,ghrelin is positively associated with BMI.

  19. Postprandial ghrelin response is reduced in patients with Parkinson's disease and idiopathic REM sleep behaviour disorder: a peripheral biomarker for early Parkinson's disease?

    Science.gov (United States)

    Unger, Marcus M; Möller, Jens C; Mankel, Katharina; Eggert, Karla M; Bohne, Katharina; Bodden, Maren; Stiasny-Kolster, Karin; Kann, Peter H; Mayer, Geert; Tebbe, Johannes J; Oertel, Wolfgang H

    2011-06-01

    Ghrelin, an orexigenic peptide, has multiple functions, which include promoting gastrointestinal motility and influencing higher brain functions. Experimental data suggest that ghrelin has neuroprotective potential in the MPTP mouse model of Parkinson's disease (PD). PD patients show delayed gastric emptying and other symptoms that may relate to disturbed excretion of ghrelin. No data are available on postprandial ghrelin response in patients with PD and idiopathic REM sleep behaviour disorder (iRBD)--a condition considered a putative preclinical stage of PD. We measured fasting and postprandial ghrelin serum concentrations in 20 healthy controls, 39 (including 19 drug-naïve) PD patients and 11 iRBD patients using a commercial radioimmunoassay for total ghrelin. For statistical analysis we employed ANCOVA and post-hoc testing with Bonferroni's method. Controls showed a decrease of mean fasting ghrelin serum concentrations in the early postprandial phase, followed by a recuperation starting 60 min after the test meal and reaching a maximum at 300 min. This recuperation was less pronounced in PD and iRBD; the slope of relative postprandial ghrelin recovery was different between the investigated groups (p = 0.007). Post-hoc testing showed a difference between controls and PD patients (p = 0.002) and between controls and iRBD patients (p = 0.037). The dynamic regulation of ghrelin in response to food intake is partially impaired in subjects at putative preclinical (iRBD) and clinical stages of PD. Reduced ghrelin excretion might increase the vulnerability of nigrostriatal dopaminergic neurons as suggested by animal studies. The impaired ghrelin excretion might qualify as a peripheral biomarker and be of diagnostic or therapeutic value.

  20. Rikkunshito, a ghrelin potentiator, ameliorates anorexia-cachexia syndrome

    Directory of Open Access Journals (Sweden)

    Naoki eFujitsuka

    2014-12-01

    Full Text Available Anorexia-cachexia syndrome develops during the advanced stages of various chronic diseases in which patients exhibit a decreased food intake, weight loss, and muscle tissue wasting. For these patients, this syndrome is a critical problem leading to an increased rate of morbidity and mortality. The present pharmacological therapies for treating anorexia-cachexia have limited effectiveness. The Japanese herbal medicine rikkunshito is often prescribed for the treatment of anorexia and upper gastrointestinal disorders. Thus, rikkunshito is expected to be beneficial for the treatment of patients with anorexia-cachexia syndrome. In this review, we summarize the effects of rikkunshito and its mechanisms of action on anorexia-cachexia.Persistent loss of appetite leads to a progressive depletion of body energy stores, which is frequently associated with cachexia. Consequently, regulating appetite and energy homeostasis is critically important for treating cachexia. Ghrelin is mainly secreted from the stomach, and it plays an important role in initiating feeding, controlling gastrointestinal motility, and regulating energy expenditure. Recent clinical and basic science studies have demonstrated that the critical mechanism of rikkunshito underlies endogenous ghrelin activity. Interestingly, several components of rikkunshito target multiple gastric and central sites, and regulate the secretion, receptor sensitization, and degradation of ghrelin. Rikkunshito is effective for the treatment of anorexia, body weight loss, muscle wasting, and anxiety-related behavior. Furthermore, treatment with rikkunshito was observed to prolong survival in an animal model of cachexia. The use of a potentiator of ghrelin signaling, such as rikkunshito, may represent a novel approach for the treatment of anorexia-cachexia syndrome.

  1. Characteristic features of ghrelin cells in the gastrointestinal tract and the regulation of stomach ghrelin expression and production

    Institute of Scientific and Technical Information of China (English)

    Zheng Zhao; Takafumi Sakai

    2008-01-01

    Ghrelin was isolated as an endogenous ligand for the GH secretagogue receptor from the rat stomach. Although physiological effects of ghrelin have been revealed by numerous studies, the regulation of stomach ghrelin remains obscure, and the factor that directly regulates ghrelin expression and production has not been identified. Here, we show some data regarding the characteristic features of ghrelin cells and the regulation of stomach ghrelin. In the gastrointestinal tract, ghrelin cells were identified as opened- and closed-type cells, and it was found that the number of ghrelin cells decreased from the stomach to the colon. The postnatal change in number of ghrelin cells in the stomach showed a sexually dimorphic pattern, indicating a role of estrogen in the regulation of stomach ghrelin. In vitro studies revealed that estrogen stimulated both ghrelin expression and production and that treatment with formestane, an aromatase (estrogen synthetase) inhibitor, decreased ghrelin expression level. On the other hand, leptin was found to inhibit both basal and estrogen-stimulated ghrelin expression. Moreover, both aromatase mRNA-expressing cells and leptin cells were found to be located close to ghrelin cells in the gastric mucosa. Furthermore, we found an inverse relationship between gastric ghrelin and leptin levels in a fasting state, and we revealed relative changes in expression of gastric ghrelin, estrogen and leptin in the postnatal rats. We propose that gastric estrogen and leptin directly regulate stomach ghrelin and that the balance control through gastric estrogen and leptin contributes to the altered ghrelin expression level in some physiological states.

  2. The activity of gastric ghrelin positive cells in obese patients treated surgically.

    Directory of Open Access Journals (Sweden)

    Artur Bossowski

    2009-12-01

    Full Text Available Ghrelin is a 28 amino acid peptide hormone regulating food intake and stimulating releasement of growth hormone. It is produced in a distinct endocrine call known as X/A - like cells. The most abundant source of this very important factor in energy homeostasis is gastric fundus. Regulatory mechanisms of ghrelin synthesis and secretion in physiological and pathological states are not discovered completely. The aim of our study was evaluation of the activity of gastric X/A-like cells in obese patients before and after the most popular surgical bariatric procedures - Roux - Y Gastric Bypass (RYGB and Laparoscopic Adjustable Gastric Banding (LAGB. Obese patients in number 18 took part in the study. LAGB was performed in 7 patients and RYGB in 11 patients. Peripheral blood was taken from each patient before operation and first day, seventh day, one month and three months after surgery. Ghrelin level was determined by RIA technique. The specimen of stomach was taken from circular stapler after gastrojejunostomy during RYGB and immunohistochemical study of gastric mucosa, using the EnVision method and specific monoclonal antybodies against ghrelin was performed. The intensity of ghrelin-immunoreactivity in X/A-like cells was analyzed using Olympus Cell D image analysis system. Efficiency of bariatric procedures was estimated by EWL- excess weight loss. We observed very strong immunohistochemical reactions of gastric X/A-like cells, accompanied by lower ghrelin plasma concentration, in comparison to the control group. LAGB procedure induced increase of ghrelin plasma level while RYGB procedure induced decrease of this hormone. The main finding of the present study is the hypoactivity of gastric X/A-like cells in obese patients in comparison to the control group.

  3. Use of Ghrelin as a Treatment for Inflammatory Bowel Disease: Mechanistic Considerations

    Directory of Open Access Journals (Sweden)

    Mark D. DeBoer

    2011-01-01

    Full Text Available Inflammatory bowel diseases (IBD—and in particular Crohn's disease—are immune-mediated processes that result in denuded intestinal mucosa and can produce decreased appetite, weight loss, and systemic inflammation. Current treatments include anti-inflammatory medications, immunomodulators, and feeding interventions. Ghrelin is an endogenous orexigenic hormone that directly stimulates growth hormone release, increases gut motility, and has cardiovascular and anti-inflammatory properties. Although ghrelin levels are elevated in active IBD, administration of ghrelin in most (but not all animal models of colitis has produced improvements in disease activity and systemic inflammation. The mechanism for these effects is not known but may relate to decreased inflammation, increased motility, increased appetite, and increased colonic blood flow. Human trials have not been performed, however, and more research is clearly needed.

  4. The role of ghrelin, leptin and insulin in foetal development

    Directory of Open Access Journals (Sweden)

    Magdalena Warchoł

    2014-06-01

    Full Text Available introduction and objective. The growing epidemic of childhood obesity has forced scientists to search for methods to prevent feeding disorders. Increasing interest in appetite regulating hormones has revealed their influence on energy homeostasis after birth or even in[i] utero[/i]. state of knowledge. The presence of ghrelin in the stomach of human foetuses and the distinctive production in the pancreas of neonates suggests the role of ghrelin in pre- and post-natal development. The neonatal period appears to be a critical time for the formation of adipose tissue-hypothalamus circuits, thus the amount of adipocytes in foetal life may be a major regulator of food intake. Insulin’s orexigenic effect in the arcuate nucleus of the hypothalamus can be a major modulator of foetal development. objective. This review, based on available literature, aims to analyses the role of appetite regulating hormones in foetal development. summary. Different concentrations of hormones, such as ghrelin, leptin and insulin during foetal life raises the question whether or not they can be modulated, thereby avoiding obesity before birth. Children with pancreas agenesis showed smaller body size at birth, which emphasises the probable role of insulin in foetal growth. Study of sheep foetuses with IUGR confirmed these finding. Appetite-regulating hormones show different roles in foetal development and seem to be essential in the perinatal period.

  5. Gastric bicarbonate secretion and release of prostaglandin E2 are increased in duodenal ulcer patients but not in Helicobacter pylori-positive healthy subjects

    DEFF Research Database (Denmark)

    Mertz-Nielsen, A; Hillingsø, Jens; Frøkiaer, H

    1996-01-01

    BACKGROUND: Duodenal ulcer (DU) patients have impaired proximal duodenal mucosal bicarbonate secretion at rest and in response to luminal acid with higher acid-stimulated mucosal release of prostaglandin (PG) E2 than healthy subjects. Our purpose was to determine whether this abnormality was pres...... for the abnormally high gastric secretion of bicarbonate in inactive DU patients. The defective duodenal secretion of bicarbonate observed in these patients may be a consequence of previous ulceration rather than the mere presence of H. pylori infection.......BACKGROUND: Duodenal ulcer (DU) patients have impaired proximal duodenal mucosal bicarbonate secretion at rest and in response to luminal acid with higher acid-stimulated mucosal release of prostaglandin (PG) E2 than healthy subjects. Our purpose was to determine whether this abnormality...... was present also in the stomach of DU patients. METHODS: Simultaneous determinations of gastric and duodenal bicarbonate secretion and luminal release of PGE2 were performed in 16 healthy volunteers (5 Helicobacter pylori-positive) and 8 inactive DU patients (all H. pylori-positive). RESULTS: In healthy...

  6. Estrogen elevates the peak overnight production rate of acylated ghrelin.

    Science.gov (United States)

    Paulo, Remberto C; Brundage, Richard; Cosma, Mihaela; Mielke, Kristi L; Bowers, Cyril Y; Veldhuis, Johannes D

    2008-11-01

    Acylated ghrelin is the putatively bioactive GH secretagogue. Estradiol (E2) stimulates the synthesis rather than inhibits the metabolic clearance of acylated ghrelin. The study took place at an academic medical center. Healthy postmenopausal women participated. Interventions included prospectively randomized, double-blind separate-day iv infusions of saline or five graded doses of ghrelin in estrogen-deficient (n=12) and E2-supplemented (n=8) women. Metabolic clearance rate (MCR), volume of distribution, half-life, and secretion rate of acylated ghrelin were assessed. In pilot iv bolus ghrelin infusions, the median half-lives of acylated and total ghrelin were 21 and 36 min (Prate (638+/-12 slope units), 2) MCR of acylated ghrelin and ghrelin infusion rate (10+/-2.5 slope units), and 3) MCR and plasma concentration of acylated ghrelin (0.017+/-0.004 slope units). These data predict peak nighttime production rates of acylated ghrelin of 3.8+/-0.9 (E2) and 1.9+/-0.2 (no E2) ng/kg.min (P=0.039). Acylated ghrelin has a multifold larger distribution volume and MCR than total ghrelin. An estrogenic milieu augments synthesis and/or acylation of ghrelin peptide without altering its MCR.

  7. Diet-Induced Obesity and Ghrelin Effects on Pituitary Gonadotrophs: Immunohistomorphometric Study in Male Rats

    Directory of Open Access Journals (Sweden)

    Ristic Natasa

    2016-02-01

    Full Text Available Objective: The close relationship between energy metabolism, nutritional state, and reproductive physiology suggests that nutritional and metabolic disorders can disrupt normal reproductive function and fertility. Considering the importance of leptin and ghrelin effects in regulation of the hypothalamic-pituitary-gonadal axis, the objective of this study was to investigate the influence of obesity and centrally applied ghrelin on immunohistochemical appearance and quantitative morphology of the pituitary follicle-stimulating hormone (FSH and luteinizing hormone (LH producing cells in adult male rats. Materials and Methods: In this experimental study, animals were given two different diets: normal-fat (NF and high-fat (HF, for 4 weeks, corresponding to normal and positive energy balance (n=2×14, respectively. Each group was subsequently divided into two subgroups (n=7 receiving intracerebroventricular (ICV injections of either ghrelin [G, 1 μg/5 μL phosphate buffered saline (PBS] or vehicle (5 μL PBS, control group every 24 hours for five consecutive days. Results: Morphometric analyses showed that in HF control group, the percentage of FSH cells per unit volume of total pituitary gland tissue (in μm3, i.e. volume density (Vvc, was increased (P<0.05 by 9.1% in comparison with the NF controls. After ICV treatment with ghrelin, volume (Vc and volume density (Vvc of FSH cells in ghrelin+NF (GNF and ghrelin+HF (GHF groups remained unchanged in comparison with NF and HF controls. Volume of LH cells in HF control group was increased by 17% (P<0.05, but their Vvc was decreased by 8.3% (P<0.05 in comparison with NF controls. In GNF group, the volume of LH cells increased by 7% (P<0.05, in comparison with the NF controls, but in GHF group, the same parameter remained unchanged when compared with HF controls. The central application of ghrelin decreased the Vvc of LH cells only in GNF group by 38.9% (P<0.05 in comparison with the NF control animals

  8. Helicobacter pylori Antibiotic Resistance: Trends Over Time

    Directory of Open Access Journals (Sweden)

    Raymond G Lahaie

    2000-01-01

    Full Text Available Resistance to antibiotics can be a major problem in the treatment of bacterial infections. As the use of antibiotics increases, bacterial resistance to these agents is rising and in many cases is responsible for the failure of treatment regimens. Although the treatment of Helicobacter pylori infection requires the use of more than one antibiotic to obtain adequate eradication rates, the efficacy of the currently used antibiotic combinations has been shown to be decreased by resistance to one of the antibiotics. The use of antibiotics in regimens for the treatment of H pylori is increasing in many countries, including Canada. This increase is both in the use of these antibiotics alone for the treatment of nongastrointestinal infections and in their use in association with proton pump inhibitors for the treatment of H pylori infection. In several European and Asian countries, where resistance to antibiotics is being monitored, it has been demonstrated that H pylori resistance to metronidazole and to clarithromycin increased throughout the 1990s. Thus far, the data available in Canada do not show increased resistance to either of these antibiotics. As for other antibiotics used in the treatment of H pylori infection, such as tetracycline and amoxicillin, the rate of resistance to these agents is still very low and does not constitute a significant problem. Because the efficacy of the regimens used in the treatment of H pylori infection is compromised by resistance to the antibiotics used, it is important that H pylori resistance rates in Canada and throughout the world continue to be monitored. Only with such reliable data can the most optimal regimens be recommended.

  9. Different effects of ghrelin, des-acyl ghrelin and obestatin on gastroduodenal motility in conscious rats

    Institute of Scientific and Technical Information of China (English)

    Mineko Fujimiya; Aldhiro Asakawa; Koji Ataka; Ikuo Kato; Akio Inui

    2008-01-01

    Three peptides, ghrelin, des-acyl ghrelin and obestatin are derived from a common prohormone, preproghre-lin by posttranslational processing, originating from endocrine cells in the stomach. To examine the effects of these peptides, we applied the manometric mea-surement of gastrointestinal motility in freely moving conscious rat models. Ghrelin exerts stimulatory ef-fects on the motility of antrum and duodenum in both fed and fasted state of animals. Des-acyl ghrelin exerts inhibitory effects on the motility of antrum, but not on the motility of duodenum in the fasted state of ani-mals. Obestatin exerts inhibitory effects on the motility of antrum and duodenum in the fed state, but not in the fasted state of animals. NPY Y2 or Y4 receptors in the brain may mediate the action of ghrelin, CRF type 2 receptors in the brain mediate the action of des-acyl ghrelin, whereas CRF type 1 and type 2 receptors in the brain mediate the action of obestatin. Vagal affer-ent pathways might be involved in the action of ghre-lin, but not involved in the action of des-acyl ghrelin, whereas vagal afferent pathways might be partially involved in the action of obestatin.

  10. Metabolic aspects of the ghrelin system: Role of acylated and unacylated ghrelin in glucose homeostasis

    NARCIS (Netherlands)

    C. Gauna (Carlotta)

    2007-01-01

    textabstractIn the last decade the discovery of ghrelin, a gut peptide discovered in 1999 by Kojima and colleagues (1), has led to the identification of a complex system that introduced new perspectives in neuroendocrine and metabolic research. Ghrelin is a peptide-hormone of 28 amino acids, predomi

  11. Ghrelin, Des-Acyl Ghrelin, and Obestatin: Regulatory Roles on the Gastrointestinal Motility

    Directory of Open Access Journals (Sweden)

    Mineko Fujimiya

    2010-01-01

    Full Text Available Ghrelin, des-acyl ghrelin, and obestatin are derived from a common prohormone, preproghrelin by posttranslational processing, originating from endocrine cells in the stomach. To examine the regulatory roles of these peptides, we applied the manometric measurement of gastrointestinal motility in freely moving conscious rat or mouse model. Ghrelin exerts stimulatory effects on the motility of antrum and duodenum in both fed and fasted state of animals. Des-acyl ghrelin exerts inhibitory effects on the motility of antrum but not on the motility of duodenum in the fasted state of animals. Obestatin exerts inhibitory effects on the motility of antrum and duodenum in the fed state but not in the fasted state of animals. NPY Y2 and Y4 receptors in the brain may mediate the action of ghrelin, CRF type 2 receptor in the brain may mediate the action of des-acyl ghrelin, whereas CRF type 1 and type 2 receptors in the brain may mediate the action of obestatin. Vagal afferent pathways might be involved in the action of ghrelin, but not involved in the action of des-acyl ghrelin, whereas vagal afferent pathways might be partially involved in the action of obestatin.

  12. Cortisol and ghrelin concentrations following a cold pressor stress test in overweight individuals with and without Night Eating

    OpenAIRE

    Geliebter, Allan; Carnell, Susan; Gluck, Marci E.

    2012-01-01

    Objective To explore appetite-related hormones following stress in overweight individuals, and their interaction with Night Eating (NE) status. Method We measured plasma cortisol and ghrelin concentrations, and recorded ratings of stress and hunger in response to a physiological laboratory stressor (Cold Pressor Test, CPT) in overweight women with (n=11; NE) and without (n=17; non-NE) night eating. Results Following the CPT, cortisol (p < .001) and ghrelin (p < .05) levels increased, as did s...

  13. Leptin and ghrelin concentration in hyperthyroid cats before and after radioactive iodine therapy compared to euthyroid control cats.

    Science.gov (United States)

    Marsilio, Sina; Glanemann, Barbara; Martin, Lucile; Szladovits, Balazs; Neiger, Reto

    2017-04-19

    Leptin and ghrelin, two peptide hormones with antagonistic effects on satiety and energy balance, could be involved in the pathogenesis of weight loss and polyphagia in cats with hyperthyroidism. Leptin generally decreases appetite and increases energy expenditure, while ghrelin exerts the opposite effects. Leptin and ghrelin were measured in 42 client owned hyperthyroid cats with a body condition score (BCS) ≤ 5/9 before (T0) and 4 weeks after radioactive iodine treatment (RAIT) (T1). Dependent on the serum total thyroxine concentration concentration at T1, cats were sub-classified as still hyperthyroid (ht-ht) (n = 4), euthyroid (ht-eu) (n = 10) or hypothyroid (ht-hypo) (n = 28). Results were compared to those of 22 healthy, euthyroid control cats with a comparable BCS (≤ 5/9) and age (≥ 8 years) to hyperthyroid cats. At T0, there were no significant differences between hyperthyroid and control cats for leptin (p = 0.06) or ghrelin concentrations (p = 0.27). At T1, leptin significantly decreased in ht-hypo cats compared to T0 (p = 0.0008) despite a significantly increased body weight in this group (p = 0.0001). Serum ghrelin concentrations did not differ between hyperthyroid cats with a history of polyphagia compared to non-polyphagic cats (p = 0.42). After RAIT, ghrelin concentration significantly increased in all hyperthyroid cats (p cats with thyroid dysfunction. Leptin fluctuations occurred independently of body weight in different states of thyroid dysfunction; increasing ghrelin concentrations after RAIT suggest a ghrelin-independent mechanism for polyphagia in hyperthyroid cats.

  14. Helicobacter pylori infection and typhoid fever in Jakarta, Indonesia.

    NARCIS (Netherlands)

    Vollaard, A.M.; Verspaget, H.W.; Ali, S.; Visser, L.G.; Veenendaal, R.A.; Asten, H.A.G.H. van; Widjaja, S.; Surjadi, C.; Dissel, J.T. van

    2006-01-01

    We evaluated the association between typhoid fever and Helicobacter pylori infection, as the latter microorganism may influence gastric acid secretion and consequently increase susceptibility to Salmonella typhi infection. Anti-H. pylori IgG and IgA antibody titres (ELISA) and gastrin concentration

  15. Molecular Mechanisms of Antibiotic Resistance in Helicobacter pylori

    NARCIS (Netherlands)

    M.M. Gerrits (Monique)

    2004-01-01

    textabstractAn estimated 4 to 5 million individuals in the Netherlands are actively infected with Helicobacter pylori. Eradication of this bacterium becomes more difficult as the prevalence of antibiotic resistance is increasing worldwide. Most H. pylori infections are now diagnosed by non-invasi

  16. Helicobacter pylori infection and typhoid fever in Jakarta, Indonesia.

    NARCIS (Netherlands)

    Vollaard, A.M.; Verspaget, H.W.; Ali, S.; Visser, L.G.; Veenendaal, R.A.; Asten, H.A.G.H. van; Widjaja, S.; Surjadi, C.; Dissel, J.T. van

    2006-01-01

    We evaluated the association between typhoid fever and Helicobacter pylori infection, as the latter microorganism may influence gastric acid secretion and consequently increase susceptibility to Salmonella typhi infection. Anti-H. pylori IgG and IgA antibody titres (ELISA) and gastrin concentration

  17. The impact of Helicobacter pylori on atopic disorders in childhood

    NARCIS (Netherlands)

    I.L. Holster (Ingrid); A.J. Vila (Anne J.); D. Caudri (Daan); C.M. den Hoed (Caroline); G.I. Perez; M.J. Blaser (Martin J.); J.C. de Jongste (Johan); E.J. Kuipers (Ernst)

    2012-01-01

    textabstractBackground: The prevalence of Helicobacter pylori in Western populations has steadily decreased. This has been suggested as one of the factors involved in the recent increase of asthma and allergy. Some studies have reported a negative association between H. pylori and asthma and

  18. Treatment of Helicobacter pylori

    Institute of Scientific and Technical Information of China (English)

    Adam Harris

    2001-01-01

    @@ INTRODUCTION Using an evidence-based approach this review discusses the current treatment of Helicobacter pylori infection in patients with peptic ulcer disease, functional (non-ulcer)dyspepsia or gastro-oesophageal reflux disease (GORD).It also briefly addresses the potential role of eradication of H . pylori in preventing gastric cancer .

  19. Effects of gastric emptying on the postprandial ghrelin response

    NARCIS (Netherlands)

    Blom, W.A.M.; Lluch, A.; Vinoy, S.; Stafleu, A.; Berg, van den R.; Holst, J.J.; Kok, F.J.; Hendriks, H.F.J.

    2006-01-01

    Distension and chemosensitization of the stomach are insufficient to induce a ghrelin response, suggesting that postgastric feedback is required. This postgastric feedback may be regulated through insulin. We investigated the relation between gastric emptying rate and the postprandial ghrelin respon

  20. Ghrelin and its Association with Nutritional and Inflammatory Status ...

    African Journals Online (AJOL)

    Ghrelin, an orexigenic peptide hormone, ... Ghrelin is a recently identified 28 amino acid peptide hormone ... in patients with chronic kidney disease (CKD). ..... deviation, NS: Nonsignificant, n: Number of subjects, eGFR: Estimated growth factor ...

  1. Overlapping binding site for the endogenous agonist, small-molecule agonists, and ago-allosteric modulators on the ghrelin receptor

    DEFF Research Database (Denmark)

    Holst, Birgitte; Frimurer, Thomas M; Mokrosinski, Jacek

    2009-01-01

    A library of robust ghrelin receptor mutants with single substitutions at 22 positions in the main ligand-binding pocket was employed to map binding sites for six different agonists: two peptides (the 28-amino-acid octanoylated endogenous ligand ghrelin and the hexapeptide growth hormone......, and PheVI:23 on the opposing face of transmembrane domain (TM) VI. Each of the agonists was also affected selectively by specific mutations. The mutational map of the ability of L-692,429 and GHRP-6 to act as allosteric modulators by increasing ghrelin's maximal efficacy overlapped with the common....... It is concluded that although each of the ligands in addition exploits other parts of the receptor, a large, common binding site for both small-molecule agonists--including ago-allosteric modulators--and the endogenous agonist is found on the opposing faces of TM-III and -VI of the ghrelin receptor....

  2. Helicobacter pylori and non-malignant upper gastrointestinal diseases.

    Science.gov (United States)

    Vasapolli, Riccardo; Malfertheiner, Peter; Kandulski, Arne

    2016-09-01

    Peptic ulcer disease (PUD) has been further decreased over the last decades along with decreasing prevalence of Helicobacter pylori-associated PUD. A delayed H. pylori eradication has been associated with an increased risk of rehospitalization for complicated recurrent peptic ulcer and reemphasized the importance of eradication especially in patients with peptic ulcer bleeding (PUB). PUB associated with NSAID/aspirin intake and H. pylori revealed an additive interaction in gastric pathophysiology which favors the "test-and-treat" strategy for H. pylori in patients with specific risk factors. The H. pylori-negative and NSAID-negative "idiopathic PUD" have been increasingly observed and associated with slower healing tendency, higher risk of recurrence, and greater mortality. Helicobacter pylori-associated dyspepsia has been further investigated and finally defined by the Kyoto consensus. Helicobacter pylori eradication therapy is advised as first option in this group of patients. Only in the case of symptom persistence or recurrence after eradication therapy, dyspeptic patients should be classified as functional dyspepsia (FD). There were few new data in 2015 on the role of H. pylori infection in gastroesophageal reflux disease (GERD), and in particular Barrett's esophagus. A lower prevalence of gastric atrophy with less acid output in patients with erosive esophagitis confirmed previous findings. In patients with erosive esophagitis, no difference was observed in healing rates neither between H. pylori-positive and H. pylori-negative patients nor between patients that underwent eradication therapy compared to patients without eradication. These findings are in line with the current consensus guidelines concluding that H. pylori eradication has no effects on symptoms and does not aggravate preexisting GERD. © 2016 John Wiley & Sons Ltd.

  3. The Effect of Endurance Training on Ghrelin, Insulin, Glucose and Estrogen in Male Rats

    Directory of Open Access Journals (Sweden)

    Abbas Ghanbari-Niaki

    2014-02-01

    Full Text Available Background: Ghrelin is a 28-amino-acid peptide hormone that is secreted primarily by stomach cells with lesser amounts secreted by other cells (including the hypothalamus. The aim of present study was to examine the effects of 8 weeks aerobic training with different durations on resting plasma Ghrelin levels in male rats. Materials and Methods: Fifty adult Wistar male rats (6-8 weeks old, 270±10 g were selected and randomly divided into five groups: 30, 60 and 90 min training, sham and control groups. All experimental groups performed an 8-week treadmill running program at the same velocity at 0 gradients for 30, 60 or 90 min/day, 5 days/week. The concentration of ghrelin in blood samples was assessed after 8 weeks and 72 hours following the final training session. The ghrelin concentration was measured by ELISA. Possible statistically significant differences between groups after the exercise training intervention was determined by one way ANOVA, and LSD test was used for a post hoc analysis. Results: Resting levels of ghrelin concentration were unchanged after training. Similarly, there was no observed change in the insulin and glucose concentrations compared with the control group. However there was a significant difference in estrogen when compared with the control group. Conclusion: The data suggest that body weight reduction is amplified by exercise-induced and increases in plasma estradiol and a moderate duration exercise program.

  4. From Belly to Brain: Targeting the Ghrelin Receptor in Appetite and Food Intake Regulation

    Science.gov (United States)

    Howick, Ken; Griffin, Brendan T.; Cryan, John F.; Schellekens, Harriët

    2017-01-01

    Ghrelin is the only known peripherally-derived orexigenic hormone, increasing appetite and subsequent food intake. The ghrelinergic system has therefore received considerable attention as a therapeutic target to reduce appetite in obesity as well as to stimulate food intake in conditions of anorexia, malnutrition and cachexia. As the therapeutic potential of targeting this hormone becomes clearer, it is apparent that its pleiotropic actions span both the central nervous system and peripheral organs. Despite a wealth of research, a therapeutic compound specifically targeting the ghrelin system for appetite modulation remains elusive although some promising effects on metabolic function are emerging. This is due to many factors, ranging from the complexity of the ghrelin receptor (Growth Hormone Secretagogue Receptor, GHSR-1a) internalisation and heterodimerization, to biased ligand interactions and compensatory neuroendocrine outputs. Not least is the ubiquitous expression of the GHSR-1a, which makes it impossible to modulate centrally-mediated appetite regulation without encroaching on the various peripheral functions attributable to ghrelin. It is becoming clear that ghrelin’s central signalling is critical for its effects on appetite, body weight regulation and incentive salience of food. Improving the ability of ghrelin ligands to penetrate the blood brain barrier would enhance central delivery to GHSR-1a expressing brain regions, particularly within the mesolimbic reward circuitry. PMID:28134808

  5. Ghrelin receptor inverse agonists as a novel therapeutic approach against obesity-related metabolic disease.

    Science.gov (United States)

    Abegg, Kathrin; Bernasconi, Lara; Hutter, Melanie; Whiting, Lynda; Pietra, Claudio; Giuliano, Claudio; Lutz, Thomas A; Riediger, Thomas

    2017-05-24

    Ghrelin is implicated in the control of energy balance and glucose homeostasis. The ghrelin receptor exhibits ligand-independent constitutive activity, which can be pharmacologically exploited to induce inverse ghrelin actions. Because ghrelin receptor inverse agonists (GHSR-IA) might be effective for the treatment of obesity-related metabolic disease, we tested 2 novel synthetic compounds GHSR-IA1 and GHSR-IA2. In functional cell assays, electrophysiogical and immunohistochemical experiments, we demonstrated inverse agonist activity for GHSR-IA1 and GHSR-IA2. We used healthy mice, Zucker diabetic fatty (ZDF) rats and diet-induced obese (DIO) mice to explore effects on food intake (FI), body weight (BW), conditioned taste aversion (CTA), oral glucose tolerance (OGT), pancreatic islet morphology, hepatic steatosis (HS), and blood lipids. Both compounds acutely reduced FI in mice without inducing CTA. Chronic GHSR-IA1 increased metabolic rate in chow-fed mice, suppressed FI, and improved OGT in ZDF rats. Moreover, the progression of islet hyperplasia to fibrosis in ZDF rats slowed down. GHSR-IA2 reduced FI and BW in DIO mice, and reduced fasting and stimulated glucose levels compared with pair-fed and vehicle-treated mice. GHSR-IA2-treated DIO mice showed decreased blood lipids. GHSR-IA1 treatment markedly decreased HS in DIO mice. Our study demonstrates therapeutic actions of novel ghrelin receptor inverse agonists, suggesting a potential to treat obesity-related metabolic disorders including diabetes mellitus. © 2017 John Wiley & Sons Ltd.

  6. The emerging roles of leptin and ghrelin in cardiovascular physiology and pathophysiology.

    Science.gov (United States)

    Sharma, Vijay; McNeill, John H

    2005-04-01

    Leptin and ghrelin are novel peptide hormones which are counter-regulatory in the central control of appetite. More recently, it has become clear that these hormones have a range of effects on the cardiovascular system. Leptin increases sympathetic activity, producing a pressor effect when acting on the central nervous system. However, leptin produces vasodilation by an endothelium-dependent mechanism peripherally. Ghrelin decreases sympathetic activity and has a depressor effect when acting on the central nervous system. Peripherally, ghrelin produces vasodilation by an endothelium-independent mechanism. Ghrelin improves left ventricular function and cardiac cachexia in heart failure. Leptin may contribute to cardiac cachexia, and to obesity-related cardiomyopathy by a variety of mechanisms. Leptin has pro-inflammatory, proliferative and calcification promoting effects in the vasculature. Ghrelin has recently been shown to be anti-inflammatory in the vasculature. Leptin may also produce a pro-thrombotic state through stimulation of platelet aggregation and inhibition of coagulation and fibrinolysis. The evidence for and against these effects as well as their pathophysiological significance in obesity hypertension, heart failure, atherosclerosis and thrombosis are discussed.

  7. From Belly to Brain: Targeting the Ghrelin Receptor in Appetite and Food Intake Regulation

    Directory of Open Access Journals (Sweden)

    Ken Howick

    2017-01-01

    Full Text Available Ghrelin is the only known peripherally-derived orexigenic hormone, increasing appetite and subsequent food intake. The ghrelinergic system has therefore received considerable attention as a therapeutic target to reduce appetite in obesity as well as to stimulate food intake in conditions of anorexia, malnutrition and cachexia. As the therapeutic potential of targeting this hormone becomes clearer, it is apparent that its pleiotropic actions span both the central nervous system and peripheral organs. Despite a wealth of research, a therapeutic compound specifically targeting the ghrelin system for appetite modulation remains elusive although some promising effects on metabolic function are emerging. This is due to many factors, ranging from the complexity of the ghrelin receptor (Growth Hormone Secretagogue Receptor, GHSR-1a internalisation and heterodimerization, to biased ligand interactions and compensatory neuroendocrine outputs. Not least is the ubiquitous expression of the GHSR-1a, which makes it impossible to modulate centrallymediated appetite regulation without encroaching on the various peripheral functions attributable to ghrelin. It is becoming clear that ghrelin’s central signalling is critical for its effects on appetite, body weight regulation and incentive salience of food. Improving the ability of ghrelin ligands to penetrate the blood brain barrier would enhance central delivery to GHSR-1a expressing brain regions, particularly within the mesolimbic reward circuitry.

  8. Hypothalamic mTOR signaling mediates the orexigenic action of ghrelin.

    Directory of Open Access Journals (Sweden)

    Luís Martins

    Full Text Available Current evidence suggests that ghrelin, a stomach derived peptide, exerts its orexigenic action through specific modulation of Sirtuin1 (SIRT1/p53 and AMP-activated protein kinase (AMPK pathways, which ultimately increase the expression of agouti-related protein (AgRP and neuropeptide Y (NPY in the arcuate nucleus of the hypothalamus (ARC. However, there is a paucity of data about the possible action of ghrelin on alternative metabolic pathways at this level. Here, we demonstrate that ghrelin elicits a marked upregulation of the hypothalamic mammalian target of rapamycin (mTOR signaling pathway. Of note, central inhibition of mTOR signaling with rapamycin decreased ghrelin's orexigenic action and normalized the mRNA expression of AgRP and NPY, as well as their key downstream transcription factors, namely cAMP response-element binding protein (pCREB and forkhead box O1 (FoxO1, total and phosphorylated. Taken together, these data indicate that, in addition to previous reported mechanisms, ghrelin also promotes feeding through modulation of hypothalamic mTOR pathway.

  9. Changes in ghrelin, CCK, GLP-1, and peroxisome proliferator-activated receptors in a hypoxia-induced anorexia rat model.

    Science.gov (United States)

    Duraisamy, Arul Joseph; Bayen, Susovan; Saini, Supriya; Sharma, Alpesh Kumar; Vats, Praveen; Singh, Shashi Bala

    2015-01-01

    A high-altitude environment causes appetite loss in unacclimatised humans, leading to weight reduction. Ghrelin, cholecystokinin (CCK), and glucagon like peptide-1 (GLP-1), are gut hormones involved in the regulation of food intake and energy metabolism. The liver is an important site of metabolic regulation, and together with the gut it plays a role in food intake regulation. This study intends to study the time-dependent changes occurring in plasma gut hormones, PPARα, PPARδ, and PGC1α, in the stomach and liver during hypoxia. Male Sprague Dawley rats were exposed to hypobaric hypoxia in a decompression chamber at 7620 m for different durations up to seven days. Hypoxia increased circulating ghrelin from the third day onwards while CCK and GLP-1 decreased immediately. An increase in ghrelin, ghrelin receptor protein levels, and GOAT mRNA levels in the stomach was observed. Stomach cholecystokinin receptor (CCKAR), PPARα, and PPARδ decreased. Liver CCKAR decreased during the first day of hypoxia and returned to normal levels from the third day onwards. PPARα and PGC1α expression increased while PPARδ protein levels reduced in the liver on third day. Hypoxia alters the expression of ghrelin and ghrelin receptor in the stomach, CCKAR in the liver, and PPAR and its cofactors, which might be possible role players in the contribution of gut and liver to anorexia at high altitude.

  10. Prevalence of Helicobacter pylori infection and its relation with body mass index in a Chinese population.

    Science.gov (United States)

    Xu, Chengfu; Yan, Ming; Sun, Yan; Joo, Jungsoo; Wan, Xingyong; Yu, Chaohui; Wang, Qunyan; Shen, Chao; Chen, Peng; Li, Youming; Coleman, William G

    2014-12-01

    Helicobacter pylori infection is highly prevalent worldwide. The association between obesity and H. pylori infection is controversial in the literature. This study aims to investigate the prevalence of H. pylori infection and its relation with body mass index (BMI) in a Chinese population. A cross-sectional study was performed among adults who underwent health checkups at the First Affiliated Hospital, College of Medicine, Zhejiang University in 2013. The prevalence of H. pylori infection was examined by (13)C urea breath tests, and the association between prevalence of H. pylori infection and BMI was analyzed. Of the 8820 participants enrolled, 3859 (43.8%) were positive for H. pylori infection. H. pylori-positive participants had a more unfavorable metabolic profile than H. pylori-negative participants. Overweight/obese participants showed a higher prevalence of H. pylori infection than that of lean participants, and a positive linear correlation between BMI and prevalence of H. pylori infection was observed. Both unadjusted and adjusted analysis revealed that BMI was significantly associated with risk factors of H. pylori infection. Our results showed that BMI was significantly and positively associated with H. pylori infection, and a high BMI was associated with an increased risk of the infection. © 2014 John Wiley & Sons Ltd.

  11. Comprehensive Profiling of GPCR Expression in Ghrelin-Producing Cells.

    Science.gov (United States)

    Koyama, Hiroyuki; Iwakura, Hiroshi; Dote, Katsuko; Bando, Mika; Hosoda, Hiroshi; Ariyasu, Hiroyuki; Kusakabe, Toru; Son, Choel; Hosoda, Kiminori; Akamizu, Takashi; Kangawa, Kenji; Nakao, Kazuwa

    2016-02-01

    To determine the comprehensive G protein-coupled receptor (GPCR) expression profile in ghrelin-producing cells and to elucidate the role of GPCR-mediated signaling in the regulation of ghrelin secretion, we determined GPCR expression profiles by RNA sequencing in the ghrelin-producing cell line MGN3-1 and analyzed the effects of ligands for highly expressed receptors on intracellular signaling and ghrelin secretion. Expression of selected GPCRs was confirmed in fluorescence-activated cell-sorted fluorescently tagged ghrelin-producing cells from ghrelin-promoter CreERT2/Rosa-CAG-LSL-ZsGreen1 mice. Expression levels of GPCRs previously suggested to regulate ghrelin secretion including adrenergic-β1 receptor, GPR81, oxytocin receptor, GPR120, and somatostatin receptor 2 were high in MGN3-1 cells. Consistent with previous reports, isoproterenol and oxytocin stimulated the Gs and Gq pathways, respectively, whereas lactate, palmitate, and somatostatin stimulated the Gi pathway, confirming the reliability of current assays. Among other highly expressed GPCRs, prostaglandin E receptor 4 agonist prostaglandin E2 significantly stimulated the Gs pathway and ghrelin secretion. Muscarine, the canonical agonist of cholinergic receptor muscarinic 4, stimulated both the Gq and Gi pathways. Although muscarine treatment alone did not affect ghrelin secretion, it did suppress forskolin-induced ghrelin secretion, suggesting that the cholinergic pathway may play a role in counterbalancing the stimulation of ghrelin by Gs (eg, by adrenaline). In addition, GPR142 ligand tryptophan stimulated ghrelin secretion. In conclusion, we determined the comprehensive expression profile of GPCRs in ghrelin-producing cells and identified two novel ghrelin regulators, prostaglandin E2 and tryptophan. These results will lead to a greater understanding of the physiology of ghrelin and facilitate the development of ghrelin-modulating drugs.

  12. Ablations of ghrelin and ghrelin receptor exhibit differential metabolic phenotypes and thermogenic capacity during aging.

    Directory of Open Access Journals (Sweden)

    Xiaojun Ma

    Full Text Available BACKGROUND: Obesity is a hallmark of aging in many Western societies, and is a precursor to numerous serious age-related diseases. Ghrelin (Ghrl, via its receptor (growth hormone secretagogue receptor, GHS-R, is shown to stimulate GH secretion and appetite. Surprisingly, our previous studies showed that Ghrl(-/- mice have impaired thermoregulatory responses to cold and fasting stresses, while Ghsr(-/- mice are adaptive. METHODOLOGY/PRINCIPAL FINDINGS: To elucidate the mechanism, we analyzed the complete metabolic profiles of younger (3-4 months and older (10-12 months Ghrl(-/- and Ghsr(-/- mice. Food intake and locomotor activity were comparable for both null mice and their wild-type (WT counterparts, regardless of age. There was also no difference in body composition between younger null mice and their WT counterparts. As the WT mice aged, as expected, the fat/lean ratio increased and energy expenditure (EE decreased. Remarkably, however, older Ghsr(-/- mice exhibited reduced fat/lean ratio and increased EE when compared to older WT mice, thus retaining a youthful lean and high EE phenotype; in comparison, there was no significant difference with EE in Ghrl(-/- mice. In line with the EE data, the thermogenic regulator, uncoupling protein 1 (UCP1, was significantly up-regulated in brown adipose tissue (BAT of Ghsr(-/- mice, but not in Ghrl(-/- mice. CONCLUSIONS: Our data therefore suggest that GHS-R ablation activates adaptive thermogenic function(s in BAT and increases EE, thereby enabling the retention of a lean phenotype. This is the first direct evidence that the ghrelin signaling pathway regulates fat-burning BAT to affect energy balance during aging. This regulation is likely mediated through an as-yet-unidentified new ligand of GHS-R.

  13. Vagal stimulation modulates inflammation through a ghrelin mediated mechanism in traumatic brain injury

    OpenAIRE

    Bansal, V; Ryu, SY; Lopez, N; Allexan, S; Krzyzaniak, M; Eliceiri, B; Baird, A.; Coimbra, R

    2012-01-01

    Traumatic brain injury (TBI) releases a cascade of inflammatory cytokines. Vagal nerve stimulation (VNS) and ghrelin have known anti-inflammatory effects; furthermore, ghrelin release is stimulated by acetylcholine. We hypothesized VNS decreases post-TBI inflammation through a ghrelin-mediated mechanism. TBI was created in five groups of mice: sham, TBI, TBI/ghrelin, TBI/VNS, and TBI/VNS/ghrelin receptor antagonist (GRa). Serum and tissue ghrelin, and serum TNF-αwere measured. Ghrelin increas...

  14. Higher ghrelin and lower leptin secretion are associated with lower LH secretion in young amenorrheic athletes compared with eumenorrheic athletes and controls.

    Science.gov (United States)

    Ackerman, Kathryn E; Slusarz, Katherine; Guereca, Gabriela; Pierce, Lisa; Slattery, Meghan; Mendes, Nara; Herzog, David B; Misra, Madhusmita

    2012-04-01

    Amenorrhea is common in young athletes and is associated with low fat mass. However, hormonal factors that link decreased fat mass with altered gonadotropin pulsatility and amenorrhea are unclear. Low levels of leptin (an adipokine) and increased ghrelin (an orexigenic hormone that increases as fat mass decreases) impact gonadotropin pulsatility. Studies have not examined luteinizing hormone (LH) secretory dynamics in relation to leptin or ghrelin secretory dynamics in adolescent and young adult athletes. We hypothesized that 1) young amenorrheic athletes (AA) would have lower LH and leptin and higher ghrelin secretion than eumenorrheic athletes (EA) and nonathletes and 2) higher ghrelin and lower leptin would be associated with lower LH secretion. This was a cross-sectional study. We examined ghrelin and leptin secretory patterns (over 8 h, from 11 PM to 7 AM) in relation to LH secretory patterns in AA, EA, and nonathletes aged 14-21 yr. Ghrelin and leptin were assessed every 20 min and LH every 10 min. Groups did not differ for age, bone age, or BMI. However, fat mass was lower in AA than in EA and nonathletes. AA had lower LH and higher ghrelin pulsatile secretion and AUC than nonathletes and lower leptin pulsatile secretion and AUC than EA and nonathletes. Percent body fat was associated positively with LH and leptin secretion and inversely with ghrelin. In a regression model, ghrelin and leptin secretory parameters were associated independently with LH secretory parameters. We conclude that higher ghrelin and lower leptin secretion in AA related to lower fat mass may contribute to altered LH pulsatility and amenorrhea.

  15. Associations between serum ghrelin and knee symptoms, joint structures and cartilage or bone biomarkers in patients with knee osteoarthritis.

    Science.gov (United States)

    Wu, J; Wang, K; Xu, J; Ruan, G; Zhu, Q; Cai, J; Ren, J; Zheng, S; Zhu, Z; Otahal, P; Ding, C

    2017-09-01

    The roles of ghrelin in knee osteoarthritis (OA) are unclear. This study aimed to examine cross-sectional associations of ghrelin with knee symptoms, joint structures and cartilage or bone biomarkers in patients with knee OA. This study included 146 patients with symptomatic knee OA. Serum levels of ghrelin and cartilage or bone biomarkers including cartilage oligomeric matrix protein (COMP), cross linked C-telopeptide of type I collagen (CTXI), cross linked N-telopeptide of type I collagen (NTXI), N-terminal procollagen III propeptide (PIIINP), and matrix metalloproteinase (MMP)-3, 10, 13 were measured using Enzyme-linked immunosorbent assay (ELISA). Knee symptoms were assessed using the Western Ontario and McMaster Universities Arthritis Index (WOMAC). Infrapatellar fat pad (IPFP) volume, IPFP signal intensity alternation, cartilage defects, bone marrow lesions (BMLs) and effusion-synovitis were assessed using the (MRI). Osteophytes and joint space narrowing (JSN) were assessed using the Osteoarthritis Research Society International atlas. After adjustment for potential confounders, ghrelin quartiles were positively associated with knee symptoms including pain, stiffness, dysfunction and total score (quartile 4 vs 1: β 24.19, 95% CI 8.13-40.25). Ghrelin quartiles were also significantly associated with increased IPFP signal intensity alteration (quartile 4 vs 1: OR 3.57, 95% CI 1.55-8.25) and NTXI, PIIINP, MMP3 and MMP13. Ghrelin was not significantly associated with other joint structures and biomarkers. Serum levels of ghrelin were significantly associated with increased knee symptoms, IPFP signal intensity alteration and serum levels of MMP3, MMP13, NTXI and PIIINP, suggesting that ghrelin may have a role to play in knee OA. Copyright © 2017 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  16. Mechanism of Cytosolic Phospholipase A2 Activation in Ghrelin Protection of Salivary Gland Acinar Cells against Ethanol Cytotoxicity

    Directory of Open Access Journals (Sweden)

    Bronislaw L. Slomiany

    2010-01-01

    Full Text Available Ghrelin, a peptide hormone, newly identified in oral mucosal tissues, has emerged recently as an important mediator of the processes of mucosal defense. Here, we report on the mechanism of ghrelin protection against ethanol cytotoxicity in rat sublingual salivary gland cells. The protective effect of ghrelin was associated with the increase in NO and PGE2, and upregulation in cytosolic phospholipase A2 (cPLA2 activity and arachidonic acid (AA release. The loss in countering effect of ghrelin occurred with cNOS inhibitor, L-NAME, as well as indomethacin and COX-1 inhibitor, SC-560, while COX-2 inhibitor, NS-398, and iNOS inhibitor, 1400W, had no effect. The effect of L-NAME was reflected in the inhibition of ghrelin-induced cell capacity for NO production, cPLA2 activation and PGE2 generation, whereas indomethacin caused only the inhibition in PGE2. Moreover, the ghrelin-induced up-regulation in AA release was reflected in the cPLA2 phosphorylation and S-nitrosylation. Inhibition in ghrelin-induced S-nitrosylation was attained with L-NAME, whereas the ERK inhibitor, PD98059, caused the blockage in cPLA2 protein phosphorylation as well as S-nitrosylation. Thus, ghrelin protection of salivary gland cells against ethanol involves cNOS-derived NO induction of cPLA2 activation through S-nitrosylation for the increase in AA release at the site of COX-1 action for PGE2 synthesis.

  17. Effects of intravenous ghrelin injection on plasma growth hormone, insulin and glucose concentrations in calves at weaning.

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    Fukumori, Rika; Mita, Takako; Sugino, Toshihisa; Hasegawa, Yoshihisa; Kojima, Masayasu; Kangawa, Kenji; Obitsu, Taketo; Taniguchi, Kohzo

    2013-04-01

    Ghrelin action, which stimulates growth hormone (GH) secretion, may alter during the weaning period in calves. Our objective was to compare the effects of intravenous ghrelin injection on plasma GH, insulin and glucose concentrations in calves around the weaning period. Four Holstein bull calves were fed whole milk and allowed free access to solid feeds, and weaned at 7 weeks of age. Measurements were performed at weeks 1, 2, 4, 6, 7, 9, 11 and 13, when calves were intravenously injected with ghrelin (1.0 μg/kg body weight (BW)) through a catheter, and jugular blood samples were obtained temporally relative to the injection time. Estimated digestible energy intake per metabolic BW transiently decreased at week 7 because of low solid intake immediately after weaning, and thereafter gradually increased. Plasma insulin and glucose concentrations were not affected by ghrelin injection at all ages. In contrast, plasma GH concentrations increased with ghrelin injection at all ages. The incremental area of GH at week 7 was greatest and significantly higher compared with weeks 2, 4, 6 and 9. This result suggests that nutrient insufficiency immediately after weaning enhances GH responsiveness to ghrelin.

  18. A hypothesis for a possible synergy between ghrelin and exercise in patients with cachexia: Biochemical and physiological bases.

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    Fuoco, Domenico; Kilgour, Robert D; Vigano, Antonio

    2015-12-01

    This article reviews the biochemical and physiological observations underpinning the synergism between ghrelin and ghrelin agonists with exercise, especially progressive resistance training that has been shown to increase muscle mass. The synergy of ghrelin agonists and physical exercise could be beneficial in conditions where muscle wasting is present, such as that found in patients with advanced cancer. The principal mechanism that controls muscle anabolism following the activation of the ghrelin receptor in the central nervous system involves the release of growth hormone/insulin-like growth factor-1 (GH/IGF-1). GH/IGF-1 axis has a dual pathway of action on muscle growth: (a) a direct action on muscle, bone and fat tissue and (b) an indirect action via the production of both muscle-restricted mIGF-1 and anti-cachectic cytokines. Progressive resistance training is a potent inducer of the secretion the muscle-restricted IGF-1 (mIGF-1) that enhances protein synthesis, increases lean body mass and eventually leads to the improvement of muscle strength. Thus, the combination of ghrelin administration with progressive resistance training may serve to circumvent ghrelin resistance and further reduce muscle wasting, which are commonly associated with cachexia. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Carob pulp preparation rich in insoluble dietary fiber and polyphenols enhances lipid oxidation and lowers postprandial acylated ghrelin in humans.

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    Gruendel, Sindy; Garcia, Ada L; Otto, Baerbel; Mueller, Corinna; Steiniger, Jochen; Weickert, Martin O; Speth, Maria; Katz, Norbert; Koebnick, Corinna

    2006-06-01

    Ghrelin is an orexigenic hormone that may affect substrate utilization in humans. Ghrelin is influenced by macronutrients, but the effects of insoluble dietary fiber and polyphenols are unknown. We investigated the effects of a polyphenol-rich insoluble dietary fiber preparation from carob pulp (carob fiber) on postprandial ghrelin responses and substrate utilization. Dose-dependent effects of the consumption of carob fiber were investigated in a randomized, single-blind, crossover study in 20 healthy subjects, aged 22-62 y. Plasma total and acylated ghrelin, triglycerides, and serum insulin and nonesterified fatty acids (NEFA) levels were repeatedly assessed before and after ingestion of an isocaloric standardized liquid meal with 0, 5, 10, or 20 g of carob fiber over a 300-min period. The respiratory quotient (RQ) was determined after consumption of 0 or 20 g of carob fiber. Carob fiber intake lowered acylated ghrelin to 49.1%, triglycerides to 97.2%, and NEFA to 67.2% compared with the control meal (P fiber-enriched liquid meal. Postprandial energy expenditure was increased by 42.3% and RQ was reduced by 99.9% after a liquid meal with carob fiber compared with a control meal (P pulp preparation, an insoluble dietary fiber rich in polyphenols, decreases postprandial responses of acylated ghrelin, triglycerides, and NEFA and alters RQ, suggesting a change toward increased fatty acid oxidation. These results indicate that carob fiber might exert beneficial effects in energy intake and body weight.

  20. Protective but not anticonvulsant effects of ghrelin and JMV-1843 in the pilocarpine model of Status epilepticus.

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    Chiara Lucchi

    Full Text Available In models of status epilepticus ghrelin displays neuroprotective effects mediated by the growth hormone secretagogue-receptor 1a (GHS-R1a. This activity may be explained by anticonvulsant properties that, however, are controversial. We further investigated neuroprotection and the effects on seizures by comparing ghrelin with a more effective GHS-R1a agonist, JMV-1843. Rats were treated either with ghrelin, JMV-1843 or saline 10 min before pilocarpine, which was used to induce status epilepticus. Status epilepticus, developed in all rats, was attenuated by diazepam. No differences were observed among the various groups in the characteristics of pilocarpine-induced seizures. In saline group the area of lesion, characterized by lack of glial fibrillary acidic protein immunoreactivity, was of 0.45 ± 0.07 mm(2 in the hippocampal stratum lacunosum-moleculare, and was accompanied by upregulation of laminin immunostaining, and by increased endothelin-1 expression. Both ghrelin (P<0.05 and JMV-1843 (P<0.01 were able to reduce the area of loss in glial fibrillary acidic protein immunostaining. In addition, JMV-1843 counteracted (P<0.05 the changes in laminin and endothelin-1 expression, both increased in ghrelin-treated rats. JMV-1843 was able to ameliorate neuronal survival in the hilus of dentate gyrus and medial entorhinal cortex layer III (P<0.05 vs saline and ghrelin groups. These results demonstrate diverse protective effects of growth hormone secretagogues in rats exposed to status epilepticus.

  1. Protective but Not Anticonvulsant Effects of Ghrelin and JMV-1843 in the Pilocarpine Model of Status epilepticus

    Science.gov (United States)

    Lucchi, Chiara; Curia, Giulia; Vinet, Jonathan; Gualtieri, Fabio; Bresciani, Elena; Locatelli, Vittorio; Torsello, Antonio; Biagini, Giuseppe

    2013-01-01

    In models of status epilepticus ghrelin displays neuroprotective effects mediated by the growth hormone secretagogue-receptor 1a (GHS-R1a). This activity may be explained by anticonvulsant properties that, however, are controversial. We further investigated neuroprotection and the effects on seizures by comparing ghrelin with a more effective GHS-R1a agonist, JMV-1843. Rats were treated either with ghrelin, JMV-1843 or saline 10 min before pilocarpine, which was used to induce status epilepticus. Status epilepticus, developed in all rats, was attenuated by diazepam. No differences were observed among the various groups in the characteristics of pilocarpine-induced seizures. In saline group the area of lesion, characterized by lack of glial fibrillary acidic protein immunoreactivity, was of 0.45±0.07 mm2 in the hippocampal stratum lacunosum-moleculare, and was accompanied by upregulation of laminin immunostaining, and by increased endothelin-1 expression. Both ghrelin (P<0.05) and JMV-1843 (P<0.01) were able to reduce the area of loss in glial fibrillary acidic protein immunostaining. In addition, JMV-1843 counteracted (P<0.05) the changes in laminin and endothelin-1 expression, both increased in ghrelin-treated rats. JMV-1843 was able to ameliorate neuronal survival in the hilus of dentate gyrus and medial entorhinal cortex layer III (P<0.05 vs saline and ghrelin groups). These results demonstrate diverse protective effects of growth hormone secretagogues in rats exposed to status epilepticus. PMID:24015271

  2. Oxytocin and dopamine stimulate ghrelin secretion by the ghrelin-producing cell line, MGN3-1 in vitro.

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    Iwakura, Hiroshi; Ariyasu, Hiroyuki; Hosoda, Hiroshi; Yamada, Go; Hosoda, Kiminori; Nakao, Kazuwa; Kangawa, Kenji; Akamizu, Takashi

    2011-07-01

    To understand the physiological role of ghrelin, it is crucial to study both the actions of ghrelin and the regulation of ghrelin secretion. Although ghrelin actions have been extensively revealed, the direct factors regulating ghrelin secretion by ghrelin-producing cells (X/A-like cells), however, is not fully understood. In this study, we examined the effects of peptide hormones and neurotransmitters on in vitro ghrelin secretion by the recently developed ghrelin-producing cell line MGN3-1. Oxytocin and vasopressin significantly stimulated ghrelin secretion by MGN3-1 cells. Because MGN3-1 cells express only oxytocin receptor mRNA, not vasopressin receptor mRNA, oxytocin is the likely regulator, with the effect of vasopressin mediated by a cross-reaction. We also discovered that dopamine stimulates ghrelin secretion from MGN3-1 cells in a similar manner to the previously known ghrelin stimulators, epinephrine and norepinephrine. MGN3-1 cells expressed mRNA encoding dopamine receptors D1a and D2. The dopamine receptor D1 agonist fenoldopam stimulated ghrelin secretion, whereas the D2, D3 agonist bromocriptine did not. Furthermore, the D1 receptor antagonist SKF83566 attenuated the stimulatory effect of dopamine. These results indicate that the stimulatory effect of dopamine on ghrelin secretion is mediated by the D1a receptor. In conclusion, we identified two direct regulators of ghrelin, oxytocin and dopamine. These findings will provide new direction for further studies seeking to further understand the regulation of ghrelin secretion, which will in turn lead to greater understanding of the physiological role of ghrelin.

  3. Polymorphisms at Locus 4p14 of Toll-Like Receptors TLR-1 and TLR-10 Confer Susceptibility to Gastric Carcinoma in Helicobacter pylori Infection.

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    M Ravishankar Ram

    Full Text Available Helicobacter pylori (H. pylori -induced gastric inflammation impacts the functions of leptin- and ghrelin-producing cells in the gastroduodenum. Inflammation resulting from H. pylori sensing via Toll-like receptors (TLRs and the associated downstream signaling largely remain ambiguous. Here, we investigated the role of gut hormones, pro-inflammatory cytokines and single nucleotide polymorphisms (SNPs associated with TLR 4p14 in H. pylori disease in 30 subjects with non-ulcer dyspepsia (NUD, 40 with peptic ulcer disease (PUD and 15 with gastric cancer (GC subjects positive and negative for H. pylori infection. The level of pro-inflammatory cytokines was directly proportional to the severity of gastritis, and disease status influenced the levels of gut hormones and pro-inflammatory cytokines. TLR-1 SNPs rs4833095 and TLR-10 SNPs rs10004195 and were directly associated with H. pylori disease, and were up-regulated in the presence of H. pylori in a genotype-independent manner. We concluded that TLR-1 rs4833095 and TLR10 rs10004195 confer susceptibility to development of gastroduodenal disease, especially GC in H.pylori disease.

  4. Tissue distribution and effects of fasting and obesity on the ghrelin axis in mice.

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    Morash, Michael G; Gagnon, Jeffrey; Nelson, Stephanie; Anini, Younes

    2010-08-09

    Ghrelin is a 28 amino acid peptide hormone derived from the 117 amino acid proghrelin, following cleavage by proprotein convertase 1 (PC1). In this study, we comprehensively assessed the tissue distribution and the effect of fasting and obesity on preproghrelin, Exon-4D, PC1 and GOAT expression and proghrelin-derived peptide (PGDP) secretion. The stomach was the major source of preproghrelin expression and PDGPs, followed by the small intestine. The remaining peripheral tissues (including the brain and pancreas) contained negligible expression levels. We detected obestatin in all stomach proghrelin cells, however, 22% of proghrelin cells in the small intestine did not express obestatin. There were strain differences in ghrelin secretion in response to fasting between CD1 and C57BL/6 mice. After a 24 hour-fast, CD1 mice had increased plasma levels of total ghrelin and obestatin with no change in preproghrelin mRNA or PGDP tissues levels. C57BL/6 mice showed a different response to a 24 hour-fast having increased proghrelin mRNA expression, stomach acylated ghrelin peptide and no change in plasma obestatin in C57BL/6 mice. In obese mice (ob/ob and diet-induced obesity (DIO)) there was a significant increase in preproghrelin mRNA levels while tissue and plasma PGDP levels were significantly reduced. Fasting did not affect PGDP in obese mice. Obese models displayed differences in GOAT expression, which was elevated in DIO mice, but reduced in ob/ob mice. We did not find co-localization of the leptin receptor in ghrelin expressing stomach cells, ruling out a direct effect of leptin on stomach ghrelin synthesis and secretion.

  5. Serum leptin and ghrelin in chronic hepatitis C patients with steatosis

    Institute of Scientific and Technical Information of China (English)

    Christos Pavlidis; Georgios I Panoutsopoulos; Dina Tiniakos; Sotirios Koutsounas; John Vlachogiannakos; Irini Zouboulis-Vafiadis

    2011-01-01

    AIM: To determine the associations between leptin and ghrelin concentrations and sustained virological response (SVR) in chronic hepatitis C patients with steatosis. METHODS: We retrospectively assessed 56 patients infected with hepatitis C virus (HCV) genotype-1 and 40 with HCV genotype-3. Patients with decompensated cirrhosis, and those with other causes of chronic liver disease, were excluded. Serum HCV-RNA concentrations were measured before the initiation of treatment; at weeks 12 (for genotype 1 patients), 24 and 48 during treatment; and 24 wk after the end of treatment. Genotype was determined using INNO-LIPA HCV assays, and serum leptin and ghrelin concentrations were measured using enzyme-linked immunosorbent assay. Biopsy specimens were scored according to the Ishak system and steatosis was graded as mild, moderate, or severe, according to the Brunt classification. RESULTS: Overall, SVR was positively related to the presence of genotype-3, to biopsy-determined lower histological stage of liver disease, and lower grade of steatosis. Patients ≥ 40 years old tended to be less responsive to therapy. In genotype-1 infected patients, SVR was associated with a lower grade of liver steatosis, milder fibrosis, and an absence of insulin resistance. Genotype-1 infected patients who did not achieve SVR had significantly higher leptin concentrations at baseline, with significant increases as the severity of steatosis worsened, whereas those who achieved SVR had higher ghrelin concentrations. In genotype-3 infected patients, SVR was associated only with fibrosis stage and lower homeostasis model assessment insulin resistance at baseline, but not with the degree of steatosis or leptin concentrations. Genotype-3 infected patients who achieved SVR showed significant decreases in ghrelin concentration at end of treatment. Baseline ghrelin concentrations were elevated in responders of both genotypes who had moderate and severe steatosis. CONCLUSION: Increased serum leptin

  6. Ghrelin negatively affects the function of ovarian follicles in mature pigs by direct action on basal and gonadotropin-stimulated steroidogenesis.

    Science.gov (United States)

    Rak-Mardyła, Agnieszka; Wróbel, Anna; Gregoraszczuk, Ewa L

    2015-04-01

    We previously showed that expression of ghrelin messenger RNA is significantly increased in the ovaries of cycling pigs but not in prepubertal animals and that ghrelin stimulates estradiol (E2) secretion by ovarian follicles in prepubertal animals. The present study investigated in vitro the role of ghrelin in regulating the ovarian steroidogenesis during estrus cycle in mature pigs. Small (SFs), medium (MFs), and large (LFs) ovarian follicles were collected on days 4 to 6, 10 to 12, and 16 to 18 of the estrous cycle from cycling pigs and exposed to 20, 100, and 500 pg/mL ghrelin for 24 hours. In additional experiments, MFs were exposed to ghrelin plus 100 ng/mL follicle-stimulating hormone (FSH) or luteinizing hormone (LH). Levels of progesterone (P4), testosterone (T), and E2 in culture medium were determined by enzyme-linked immunosorbent assay, and the expression of the steroid pathway enzymes 3β hydroxysteroid dehydrogenase (HSD), 17β-HSD, and cytochrome P450 aromatase (CYP19) was evaluated by Western blotting. Ghrelin had no effect on steroid secretion when present at 20 pg/mL, its concentration in follicular fluid, whereas at 100 pg/mL and 500 pg/mL, its concentration in serum, ghrelin significantly decreased secretion of P4, T, and E2. Moreover, all concentrations of ghrelin decreased steroid secretion in FSH- and LH-stimulated follicles. Western blot analysis showed that ghrelin inhibited expression of 3β-HSD, 17β-HSD, and CYP19 proteins. These results suggest that ghrelin, by direct inhibition of 3β-HSD, 17β-HSD, and CYP19 protein expression, inhibits LH- and FSH-stimulated steroid secretion by ovarian follicles, thus negatively affecting ovarian steroidogenesis in mature pigs.

  7. Preliminary results on ghrelin mRNA quantification in buffalo calves during fasting and refeeding by real-time reverse transcription PCR assay

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    G. Neglia

    2010-02-01

    Full Text Available The aim of this trial was to evaluate ghrelin response to milk administration in 20 days old buffalo calves. The trial was carried out on 5 female buffalo calves with a mean age of 21.2±2.8 days. Five blood samples were collected from each animal into EDTA tubes, starting at 07.00 until 15.00, at 2-h intervals. At 09.00, after the second blood sample, replaced milk was administered to the calves. Blood samples were immediately placed at 4°C until processing, which was performed on the same day. We used real-time reverse transcription PCR system to detect the expression of ghrelin mRNA levels in blood of buffalo calves. Two calves showed a low ghrelin concentration at the start of the trial (Group A = low ghrelin concentration and three calves a high ghrelin concentration (Group B = high ghrelin concentration. Ghrelin expression was significantly higher either two hours (P<0.01 and just before feeding (P<0.05 in Group B vs. Group A. However, in both cases, a significant (P<0.05 difference was observed within each group between -2 and 6 hours after feeding. Therefore, ghrelin concentration tended to increase in animals that showed low levels and, similarly, it lowered in animals that showed high concentration. If these results will be confirmed, may represent the evidence that also in buffalo calves the ghrelin system may affect feed intake. Further studies are needed in order to better evaluate the ghrelin system in buffalo calves.

  8. Helicobacter Pylori Infection in the Elderly

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    Jyh-Ming Liou

    2008-12-01

    Full Text Available The elderly often seek medical attention because of gastroduodenal diseases. Helicobacter pylori (H. pylori infection is associated with several gastroduodenal diseases and its prevalence increases with age worldwide. It is estimated that 10–15% of infected patients will have peptic ulcer disease and 1% of patients will have gastric cancer or mucosa-associated lymphoid tissue lymphoma. Notably, the most severe clinical outcomes, i.e., gastric cancer and complicated peptic ulcer diseases, usually occur in elderly patients. Thus the test-and-treatment strategy is not recommended for elderly patients with uninvestigated dyspepsia. However, biopsy specimens for the rapid urease test and histology should be taken from both the antrum and corpus to increase the detection rate in elderly patients, especially in those with atrophic gastritis. The urea breath test may increase the detection rate if the rapid urease test or histology are negative in elderly patients with atrophic gastritis. Standard triple therapy and sequential therapy can achieve satisfactory eradication rates for H. pylori in elderly patients. Elderly patients with peptic ulcers may have a similar benefit from treatment of H. pylori infection as non-elderly patients. Eradication of H. pylori infection may also lead to improvement in histologic grading of gastritis, but the risk of gastric cancer cannot be completely reduced, especially in patients with existing premalignant lesions.

  9. Antinociceptive Effect of Ghrelin in a Rat Model of Irritable Bowel Syndrome Involves TRPV1/Opioid Systems

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    Yuqing Mao

    2017-09-01

    Full Text Available Background/Aims: Irritable bowel syndrome (IBS, defined as recurrent abdominal pain and changes in bowel habits, seriously affects quality of life and ability to work. Ghrelin is a brain-gut hormone, which has been reported to show antinociceptive effects in peripheral pain. We investigated the effect of ghrelin on visceral hypersensitivity and pain in a rat model of IBS. Methods: Maternal deprivation (MD was used to provide a stress-induced model of IBS in Wistar rats. Colorectal distension (CRD was used to detect visceral sensitivity, which was evaluated by abdominal withdrawal reflex (AWR scores. Rats that were confirmed to have visceral hypersensitivity after MD were injected with ghrelin (10 µg/kg subcutaneously twice a week from weeks 7 to 8. [D-Lys3]-GHRP-6 (100 nmol/L and naloxone (100 nmol/L were administered subcutaneously to block growth hormone secretagogue receptor 1α (GHS-R1α and opioid receptors, respectively. Expression of transient receptor potential vanilloid type 1 (TRPV1 and µ and κ opioid receptors (MOR and KOR in colon, dorsal root ganglion (DRG and cerebral cortex tissues were detected by western blotting, quantitative real-time polymerase chain reaction (qRT-PCR, immunohistochemical analyses and immunofluorescence. Results: Ghrelin treatment increased expression of opioid receptors and inhibited expression of TRPV1 in colon, dorsal root ganglion (DRG and cerebral cortex. The antinociceptive effect of ghrelin in the rat model of IBS was partly blocked by both the ghrelin antagonist [D-Lys3]-GHRP-6 and the opioid receptor antagonist naloxone. Conclusion: The results indicate that ghrelin exerted an antinociceptive effect, which was mediated via TRPV1/opioid systems, in IBS-induced visceral hypersensitivity. Ghrelin might potentially be used as a new treatment for IBS.

  10. Helicobacter pylori-related chronic gastritis as a risk factor for colonic neoplasms.

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    Inoue, Izumi; Kato, Jun; Tamai, Hideyuki; Iguchi, Mikitaka; Maekita, Takao; Yoshimura, Noriko; Ichinose, Masao

    2014-02-14

    To summarize the current views and insights on associations between Helicobacter pylori (H. pylori)-related chronic gastritis and colorectal neoplasm, we reviewed recent studies to clarify whether H. pylori infection/H. pylori-related chronic gastritis is associated with an elevated risk of colorectal neoplasm. Recent studies based on large databases with careful control for confounding variables have clearly demonstrated an increased risk of colorectal neoplasm associated with H. pylori infection. The correlation between H. pylori-related chronic atrophic gastritis (CAG) and colorectal neoplasm has only been examined in a limited number of studies. A recent large study using a national histopathological database, and our study based on the stage of H. pylori-related chronic gastritis as determined by serum levels of H. pylori antibody titer and pepsinogen, indicated that H. pylori-related CAG confers an increased risk of colorectal neoplasm, and more extensive atrophic gastritis will probably be associated with even higher risk of neoplasm. In addition, our study suggested that the activity of H. pylori-related chronic gastritis is correlated with colorectal neoplasm risk. H. pylori-related chronic gastritis could be involved in an increased risk of colorectal neoplasm that appears to be enhanced by the progression of gastric atrophy and the presence of active inflammation.

  11. In Vitro Activity of Diphenyleneiodonium toward Multidrug-Resistant Helicobacter pylori Strains.

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    Chung, Jun-Won; Kim, Su Young; Park, Hee Jung; Chung, Chang Su; Lee, Hee Woo; Lee, Sun Mi; Kim, Inki; Pak, Jhang Ho; Lee, Gin Hyug; Jeong, Jin-Yong

    2017-09-15

    The increased resistance of Helicobacter pylori to antibiotics has increased the need to develop new treatments for this bacterium. The aim of our study was to identify new drugs with anti-H. pylori activity. We screened a small molecule library-the library of pharmacologically active compounds (LOPAC), which includes 1,280 pharmacologically active compounds-to identify inhibitors of H. pylori growth. The minimal inhibitory concentrations (MICs) of antibiotics against multidrug-resistant H. pylori strains were determined using the agar dilution method. We identified diphenyleneiodonium (DPI) as a novel anti-H. pylori agent. The MIC values for DPI were <0.03 µg/mL against all tested H. pylori strains. DPI also exhibited strong antibacterial activity against common gram-negative and gram-positive pathogenic bacteria. DPI may be a candidate anti-H. pylori drug for future development.

  12. Characterization of adult ghrelin and ghrelin receptor knockout mice under positive and negative energy balance.

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    Sun, Yuxiang; Butte, Nancy F; Garcia, Jose M; Smith, Roy G

    2008-02-01

    Ghrelin and the ghrelin receptor (GH secretagogue receptor, GHS-R), are believed to have important roles in energy homeostasis. We describe results from the first studies to be conducted in congenic (N10) adult ghrelin(-/-) and Ghsr(-/-) mice under conditions of both positive (high-fat diet) and negative (caloric restriction) energy balance. In contrast to results from young N2 mutant mice, changes in body weight and energy expenditure are not clearly distinguishable across genotypes. Although respiratory quotient was lower in mice fed a high-fat diet, no differences were evident between littermate wild-type and null genotypes. With normal chow, a modest decrease trend in respiratory quotient was detected in ghrelin(-/-) mice but not in Ghsr(-/-) mice. Under caloric restriction, the weight loss of ghrelin(-/-) and Ghsr(-/-) mice was identical to wild-type littermates, but blood glucose levels were significantly lower. We conclude that adult congenic ghrelin(-/-) and Ghsr(-/-) mice are not resistant to diet-induced obesity but under conditions of negative energy balance show impairment in maintaining glucose homeostasis. These results support our hypothesis that the primary metabolic function of ghrelin in adult mice is to modulate glucose sensing and insulin sensitivity, rather than directly regulate energy intake and energy expenditure.

  13. Antibiotic susceptibility of Helicobacter pylori in Iceland.

    Science.gov (United States)

    Gunnarsdottir, Anna Ingibjorg; Gudjonsson, Hallgrimur; Hardardottir, Hjordis; Jonsdottir, Karen Drofn; Bjornsson, Einar Stefan

    2017-09-01

    Increasing resistance of Helicobacter pylori (H. pylori) to antibiotics calls for constant re-evaluation of multidrug regimens that have been used to eradicate the infection. The aim of this study was to evaluate the current antibiotic susceptibility of H. pylori in an Icelandic cohort. Patients referred for gastroscopy were recruited prospectively. Those found to have a positive rapid urease test were included in the study. Susceptibility testing was conducted by the Epsilometer test (E-test) method for ampicillin, clarithromycin, levofloxacin, metronidazole and tetracycline. Results were obtained after three days of incubation in microaerophilic conditions at 37 °C, except for the metronidazole were the first 24 hours were anaerobic. Of the 613 patients who underwent gastroscopy, 138 (23%) had a positive rapid urease test. H. pylori was successfully cultured from 105 (76%) of the urease test positive patients and the isolates were tested for antibiotic susceptibility. Five patients had prior H. pylori eradication. Antibiotic resistance for ampicillin, clarithromycin, levofloxacin, metronidazole and tetracycline was 0%, 9%, 4%, 1% and 0%, respectively. If those who had previously undergone eradication treatment were excluded, the resistance was 0%, 6%, 3%, 1% and 0%, respectively. Clarithromycin resistance was higher amongst women than men, 13% vs. 5%, however, not significantly. Clarithromycin resistance was 60% amongst those who had previously received eradication treatment compared to 6% of those who had not (p pylori isolates can be considered relatively low. Therefore, in the current cohort, standard triple-drug clarithromycin-containing regimen should remain the first-line treatment against H. pylori.

  14. Role of ghrelin on testosterone secretion and the mRNA expression of androgen receptors in adult rat testis.

    Science.gov (United States)

    Wang, Lin; Fang, Fugui; Li, Yunsheng; Zhang, Yunhai; Pu, Yong; Zhang, XiaoYong

    2011-06-01

    The present study was designed to determine the effects of ghrelin on in vivo and in vitro secretion of testosterone (T) and the expression of androgen receptor (AR) mRNA in the adult rat testis. The distribution of growth hormone secretagogue receptors (GHS-R(1a)) in the testis was also investigated. GHS-R(1a) immunoreactivity presented mainly in Sertoli and Leydig cells, primary spermatocytes, and secondary spermatocytes. Adult rats that were intracerebroventricularly (i.c.v.) administrated different dosages (1 nmol and 3 nmol) of ghrelin could significantly inhibit the secretion of T. The experession of AR mRNA in the testis was also notably reduced with 3 nmol ghrelin. Additionaly, in vitro exposure of the Leydig cells to increasing concentrations of ghrelin resulted in no obvious changes of T secretion in the culture media and AR mRNA expression of Leydig cells. Overall, our data demonstrate that the i.c.v. injection of ghrelin plays a physiological role in T secretion and AR mRNA expression in the testis, further confirming the reproductive role of ghrelin.

  15. The effect of exercise intensity on plasma and tissue acyl ghrelin concentrations in fasted rats.

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    Fathi, Rozita; Ghanbari-Niaki, Abbass; Kraemer, Robert R; Talebi-Garakani, Elahe; Saghebjoo, Marziyeh

    2010-12-10

    This study was conducted to investigate the effect of exercise training and feeding status on plasma and tissue acyl ghrelin concentrations. Thirty-two, eight-week-old male Wistar rats (185±5g) were randomly assigned to one of four groups: high intensity (HI: 34 m/min ~80-85% VO(2)max), moderate intensity (MI: 28 m/min ~70-75% VO(2)max), low intensity (LI: 20 m/min ~50-55% VO(2)max), and sedentary control (SED) groups. All experimental groups performed a 12-week exercise program consisting of treadmill running on a 0° slope for 1 h/day, 5 days/week at their respective training intensity. Twenty four hours following the last training session the animals completed a 12h fast. Rats were then killed, blood was collected and plasma separated; the fundus and soleus muscle were excised and frozen in liquid nitrogen for later analysis. Fasting levels of circulating acyl ghrelin and acyl ghrelin content in the soleus muscle and fundus, as well as glycogen in the soleus muscle were measured. Data were analyzed using one-way ANOVA. Results demonstrated that 12 weeks of exercise training combined with a 12h fast significantly increased plasma as well as soleus muscle concentrations of acyl ghrelin in the HI and MI groups (pghrelin concentrations in the fundus (pexercise training enhances fasting plasma acyl ghrelin in an intensity-dependent manner which is accompanied by a significant increase in soleus muscle and reduction in fundus acyl ghrelin levels. Copyright © 2010 Elsevier B.V. All rights reserved.

  16. Ghrelin signalling and obesity: at the interface of stress, mood and food reward.

    Science.gov (United States)

    Schellekens, Harriët; Finger, Beate C; Dinan, Timothy G; Cryan, John F

    2012-09-01

    The neuronal circuitry underlying the complex relationship between stress, mood and food intake are slowly being unravelled and several studies suggest a key role herein for the peripherally derived hormone, ghrelin. Evidence is accumulating linking obesity as an environmental risk factor to psychiatric disorders such as stress, anxiety and depression. Ghrelin is the only known orexigenic hormone from the periphery to stimulate food intake. Plasma ghrelin levels are enhanced under conditions of physiological stress and ghrelin has recently been suggested to play an important role in stress-induced food reward behaviour. In addition, chronic stress or atypical depression has often demonstrated to correlate with an increase in ingestion of caloric dense 'comfort foods' and have been implicated as one of the major contributor to the increased prevalence of obesity. Recent evidence suggests ghrelin as a critical factor at the interface of homeostatic control of appetite and reward circuitries, modulating the hedonic aspects of food intake. Therefore, the reward-related feeding of ghrelin may reveal itself as an important factor in the development of addiction to certain foods, similar to its involvement in the dependence to drugs of abuse, including alcohol. This review will highlight the accumulating evidence demonstrating the close interaction between food, mood and stress and the development of obesity. We consider the ghrelinergic system as an effective target for the development of successful anti-obesity pharmacotherapies, which not only affects appetite but also selectively modulates the rewarding properties of food and impact on psychological well-being in conditions of stress, anxiety and depression. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Involvement of cyclooxygenase-1 and cyclooxygenase-2 activity in the therapeutic effect of ghrelin in the course of ethanol-induced gastric ulcers in rats.

    Science.gov (United States)

    Warzecha, Z; Ceranowicz, P; Dembinski, M; Cieszkowski, J; Ginter, G; Ptak-Belowska, A; Dembinski, A

    2014-02-01

    Previous studies have shown that treatment with ghrelin exhibits protective and therapeutic effects in the gut. Aim of our present investigation was to examine the influence of ghrelin administration on the healing of ethanol-induced gastric ulcers and determine the role of cyclooxygenase-1 and cyclooxygenase-2 in this effect. Our studies were performed on male Wistar rats. Gastric ulcers were induced by intragastric administration of 75% ethanol. Ghrelin alone or in combination with cyclooxygenase inhibitors was administered twice, 1 and 13 hours after ethanol application. Cyclooxygenase-1 (COX-1) inhibitor (SC-560, 10 mg/kg/dose) or COX-2 inhibitor (celecoxib, 10 mg/kg/dose) were given 30 min prior to ghrelin. Twelve or 24 hours after administration of ethanol, rats were anesthetized and experiments were terminated. The study revealed that administration of ethanol induced gastric ulcers in all animals and this effect was accompanied by the reduction in gastric blood flow and mucosal DNA synthesis. Moreover induction of gastric ulcer by ethanol significantly increased mucosal expression of mRNA for COX-2, IL-1β and TNF-α. Treatment with ghrelin significantly accelerated gastric ulcer healing. Therapeutic effect of ghrelin was associated with significant reversion of the ulcer-evoked decrease in mucosal blood flow and DNA synthesis. Ghrelin administration also caused the reduction in mucosal expression of mRNA for IL-1β and TNF-α. Addition of SC-560 slightly reduced the therapeutic effect of ghrelin in the healing of ethanol-induced ulcer and the ulcer area in rats treated SC-560 plus ghrelin was significantly smaller than that observed in rats treated with saline or SC-560 alone. Pretreatment with celecoxib, a COX-2 inhibitor, abolished therapeutic effect of ghrelin. We concluded that treatment with ghrelin increases healing rate of gastric ulcers evoked by ethanol and this effect is related to improvement in mucosal blood flow, an increase in mucosal cell

  18. Adipokines and ghrelin in gastric cancer cachexia

    Institute of Scientific and Technical Information of China (English)

    Mustafa Kerem; Zafer Ferahkose; Utku Tonguc Yilmaz; Hatice Pasaoglu; Ebru Ofluoglu; Abdulkadir Bedirli; Bulent Salman; Tevfik Tolga Sahin; Murat Akin

    2008-01-01

    AIM: To investigate the roles of the adipocytokines, ghrelin and leptin in gastric cancer cachexia.METHODS: Resistin, ghrelin, leptin, adiponectin, insulin and insulin-like growth factor (IGF-I), were measured in 30 healthy subjects, and 60 gastric cancer patients of which 30 suffered from cancer- induced cachexia and 30 served as a control group. The relationships between hormones, body mass index (BMI) loss ratio, age, gender, and Glasgow Prognostic Score (GPS) were investigated.RESULTS: Cachexia patients had higher tumor stage and GPS when compared with non-cachexia patients (P<0.05). Ghrelin, resistin, leptin, adiponectin and IGF-I, showed a significant correlation with BMI loss ratio and GPS (P < 0.05). A strong correlation was seen between GPS and BMI loss (R = -0.570, P < 0.0001). Multivariate analysis indicated that BMI loss was significantly independent as a predictor of ghrelin, resistin, leptin and IGF-I (P<0.05). Existence of an important significant relationship between resistin and insulin resistance was also noted.CONCLUSION: These results showed that serum ghrelin, leptin, adiponectin, and IGF-I play important roles in cachexia-related gastric cancers. No relationship was found between resistin and cancer cachexia. Also, because of the correlation between these parameters and GPS, these parameters might be used as a predictor factor.

  19. Helicobacter pylori and cancer among adults in Uganda

    Directory of Open Access Journals (Sweden)

    Owens Marilyn

    2006-11-01

    Full Text Available Abstract Data from Africa on infection with Helicobacter pylori (H. pylori are sparse. Therefore, as part of an epidemiological study of cancer in Uganda, we investigated the prevalence and determinants of antibodies against H. pylori among 854 people with different cancer types and benign tumours. Patients were recruited from hospitals in Kampala, Uganda, interviewed about various demographic and lifestyle factors and tested for antibodies against H. pylori. In all patients combined, excluding those with stomach cancer (which has been associated with H. pylori infection, the prevalence of antibodies was 87% (723/833 overall, but declined with increasing age (p = 0.02 and was lower among people who were HIV seropositive compared to seronegative (p H. pylori antibodies (odds ratio 0.8, 95% confidence intervals 0.2–2.9, p = 0.7; estimated using all other patients as controls, with adjustment for age, sex and HIV serostatus. No other cancer site or type was significantly associated with anti-H. pylori antibodies. The prevalence of H. pylori reported here is broadly in accord with results from other developing countries, although the determinants of infection and its' role in the aetiology of gastric cancer in Uganda remain unclear.

  20. Prevention of Gastric Cancer: Eradication of Helicobacter Pylori and Beyond

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    Tetsuya Tsukamoto

    2017-08-01

    Full Text Available Although its prevalence is declining, gastric cancer remains a significant public health issue. The bacterium Helicobacter pylori is known to colonize the human stomach and induce chronic atrophic gastritis, intestinal metaplasia, and gastric cancer. Results using a Mongolian gerbil model revealed that H. pylori infection increased the incidence of carcinogen-induced adenocarcinoma, whereas curative treatment of H. pylori significantly lowered cancer incidence. Furthermore, some epidemiological studies have shown that eradication of H. pylori reduces the development of metachronous cancer in humans. However, other reports have warned that human cases of atrophic metaplastic gastritis are already at risk for gastric cancer development, even after eradication of these bacteria. In this article, we discuss the effectiveness of H. pylori eradication and the morphological changes that occur in gastric dysplasia/cancer lesions. We further assess the control of gastric cancer using various chemopreventive agents.

  1. Ghrelin function in insulin release and glucose metabolism.

    Science.gov (United States)

    Dezaki, Katsuya

    2013-01-01

    Given its wide spectrum of biological activities such as growth hormone (GH) release, feeding stimulation, adiposity and cardiovascular actions, the discovery of ghrelin opened many new perspectives within neuroendocrine, metabolic and cardiovascular research, thus suggesting its possible clinical application. Circulating ghrelin is produced predominantly in the stomach, and its receptor GH secretagogue receptor (GHS-R) is expressed in a variety of central and peripheral tissues. Ghrelin, GHS-R and ghrelin O-acyltransferase (GOAT), the enzyme that promotes the acylation of the third serine residue of ghrelin, are all expressed in pancreatic islets, and this peptide is released into pancreatic microcirculations. Ghrelin inhibits insulin release in mice, rats and humans. The signal transduction mechanisms of ghrelin receptor in islet β-cells are very unique, being distinct from those utilized for GH release. Pharmacological and genetic blockade of islet-derived ghrelin markedly augments glucose-induced insulin release in vitro. Ablation of ghrelin, GHS-R or GOAT enhances insulin release and prevents impaired glucose tolerance in high-fat, diet-induced and leptin-deficient obese models. Thus, manipulation of the insulinostatic function of the ghrelin-GHS-R system, particularly that in islets, could optimize the amount of insulin release to meet the systemic demand. Ghrelin antagonism provides a novel strategy to treat type 2 diabetes with dysregulated insulin release.

  2. Obesity Impairs the Action of the Neuroendocrine Ghrelin System.

    Science.gov (United States)

    Zigman, Jeffrey M; Bouret, Sebastien G; Andrews, Zane B

    2016-01-01

    Ghrelin is a metabolic hormone that promotes energy conservation by regulating appetite and energy expenditure. Although some studies suggest that antagonizing ghrelin function attenuates body weight gain and glucose intolerance on a high calorie diet, there is little information about the metabolic actions of ghrelin in the obese state. In this review, we discuss the novel concept of obesity-induced central ghrelin resistance in neural circuits regulating behavior, and impaired ghrelin secretion from the stomach. Interestingly, weight loss restores ghrelin secretion and function, and we hypothesize that ghrelin resistance is a mechanism designed to protect a higher body weight set-point established during times of food availability, to maximize energy reserves during a time of food scarcity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. The Antidepressant-like Effects of Estrogen-mediated Ghrelin

    Science.gov (United States)

    Wang, Pu; Liu, Changhong; Liu, Lei; Zhang, Xingyi; Ren, Bingzhong; Li, Bingjin

    2015-01-01

    Ghrelin, one of the brain-gut peptides, stimulates food-intake. Recently, ghrelin has also shown to play an important role in depression treatment. However, the mechanism of ghrelin’s antidepressant-like actions is unknown. On the other hand, sex differences in depression, and the fluctuation of estrogens secretion have been proved to play a key role in depression. It has been reported that women have higher level of ghrelin expression, and ghrelin can stimulate estrogen secretion while estrogen acts as a positive feedback mechanism to up-regulate ghrelin level. Ghrelin may be a potential regulator of reproductive function, and estrogen may have additional effect in ghrelin’s antidepressantlike actions. In this review, we summarize antidepressant-like effects of ghrelin and estrogen in basic and clinical studies, and provide new insight on ghrelin’s effect in depression. PMID:26412072

  4. Is Ghrelin Synthesized in the Central Nervous System?

    Science.gov (United States)

    Cabral, Agustina; López Soto, Eduardo J.; Epelbaum, Jacques; Perelló, Mario

    2017-01-01

    Ghrelin is an octanoylated peptide that acts via its specific receptor, the growth hormone secretagogue receptor type 1a (GHSR-1a), and regulates a vast variety of physiological functions. It is well established that ghrelin is predominantly synthesized by a distinct population of endocrine cells located within the gastric oxyntic mucosa. In addition, some studies have reported that ghrelin could also be synthesized in some brain regions, such as the hypothalamus. However, evidences of neuronal production of ghrelin have been inconsistent and, as a consequence, it is still as a matter of debate if ghrelin can be centrally produced. Here, we provide a comprehensive review and discussion of the data supporting, or not, the notion that the mammalian central nervous system can synthetize ghrelin. We conclude that no irrefutable and reproducible evidence exists supporting the notion that ghrelin is synthetized, at physiologically relevant levels, in the central nervous system of adult mammals. PMID:28294994

  5. Epithelial cell kinetics of the gastric mucosa during Helicobacter pylori infection

    DEFF Research Database (Denmark)

    Holck, Susanne; Holm, I.L.; Holck, P.P.

    2007-01-01

    Helicobacter pylori is an important pathogen in major gastroduodenal diseases, including inflammation with ulceration and gastric malignancies. Alterations in H. pylori associated cell turnover in gastric epithelial cells are examined in relation to inflammatory activity, bacteria load...... and cytokines which may improve knowledge concerning the outcome of gastric diseases caused by H. pylori. Antral biopsies from 42 dyspeptic patients including 27 H. pylori-positive and 15 H. pylori-negative patients were tested for apoptotic activity by the TUNEL assay, and immuno-histochemically for p53...... and the proliferative marker Ki-67. H. pylori infection, bacteria load and inflammatory activity were associated with increased cell turnover as judged by enhanced activities of TUNEL, p53 and Ki-67. Only p53 was significantly correlated to IFN-gamma, IL-8 and IL-10. The H. pylori-positive state was furthermore...

  6. Helicobacter pylori infection and extragastric disorders in children: A critical update

    Science.gov (United States)

    Pacifico, Lucia; Osborn, John F; Tromba, Valeria; Romaggioli, Sara; Bascetta, Stefano; Chiesa, Claudio

    2014-01-01

    Helicobacter pylori (H. pylori) is a highly prevalent, serious and chronic infection that has been associated causally with a diverse spectrum of extragastric disorders including iron deficiency anemia, chronic idiopathic thrombocytopenic purpura, growth retardation, and diabetes mellitus. The inverse relation of H. pylori prevalence and the increase in allergies, as reported from epidemiological studies, has stimulated research for elucidating potential underlying pathophysiological mechanisms. Although H. pylori is most frequently acquired during childhood in both developed and developing countries, clinicians are less familiar with the pediatric literature in the field. A better understanding of the H. pylori disease spectrum in childhood should lead to clearer recommendations about testing for and treating H. pylori infection in children who are more likely to develop clinical sequelae. A further clinical challenge is whether the progressive decrease of H. pylori in the last decades, abetted by modern clinical practices, may have other health consequences. PMID:24587617

  7. Structural characterization of purine nucleoside phosphorylase from human pathogen Helicobacter pylori.

    Science.gov (United States)

    Štefanić, Zoran; Mikleušević, Goran; Luić, Marija; Bzowska, Agnieszka; Leščić Ašler, Ivana

    2017-08-01

    Microaerophilic bacterium Helicobacer pylori is a well known human pathogen involved in the development of many diseases. Due to the evergrowing infection rate and increase of H. pylori antibiotic resistence, it is of utmost importance to find a new way to attack and eradicate H. pylori. The purine metabolism in H. pylori is solely dependant on the salvage pathway and one of the key enzymes in this pathway is purine nucleoside phosphorylase (PNP). In this timely context, we report here the basic biochemical and structural characterization of recombinant PNP from the H. pylori clinical isolate expressed in Escherichia coli. Structure of H. pylori PNP is typical for high molecular mass PNPs. However, its activity towards adenosine is very low, thus resembling more that of low molecular mass PNPs. Understanding the molecular mechanism of this key enzyme may lead to the development of new drug strategies and help in the eradication of H. pylori. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Treatment of Helicobacter Pylori in Children

    Directory of Open Access Journals (Sweden)

    F Famouri

    2014-04-01

    Full Text Available Childrenwith Helicobacter infection need treatment. The aim of treatment is elimination of H.Pylori. Most patients with this infection are asymptomatic and without peptic disease. Treatment and management of these patients are controversy. Conventional Treatment: The best treatment for H. pylori eradication regimens should have cure rates of at least 80%, be without major side effects, and induce minimal bacterial resistance. Antibiotics alone have not achieved this. Luminal acidity influences both the effectiveness of some antimicrobial agents and the survival of the bacteri; thus antibiotics have been combined with acid suppression such as proton pump inhibitors (PPIs, bismuth, or H2 antagonists. The “classic” regimen is treatment twice daily for 7 days with a PPI and clarithromycin plus either amoxicillin or metronidazole Bismuth has been used in the treatment of peptic ulcer disease and 1 part o quadruple therapy for H.Pylori but compliance of children for it is low.   Sequential Therapy  Sequential therapyinvolves dual therapy with a PPI and amoxicillin for 5 days followed sequentially by clarithromycin, Tinidazole and omeperazole for 5 days or other triple therapy for 7 days. This treatment has had 97% efficacy.   Adjunctive Therapies A number of studies have showed the potential benefits of probiotic therapy in H. pylori treatment regimens.Consumption of these drugs accompanied with other medications increase H.Pylori eradication.    

  9. Helicobacter pylori in pediatrics.

    Science.gov (United States)

    Homan, Matjaž; Hojsak, Iva; Kolaček, Sanja

    2012-09-01

    This review summarizes important pediatric studies published from April 2011 up to March 2012. Proteomics profile of ulcerogenic Helicobacter pylori strains was defined in the most interesting study of the last year. The antigen stool test is becoming the "gold standard" in prevalence studies, and according to the last epidemiologic studies, the prevalence of H. pylori infection in childhood is not decreasing any more in the developed world. The resistance rate of H. pylori strains is high in children. Therefore, among other important issues concerning H. pylori in pediatrics, guidelines published by ESPGHAN and NASPGHAN last year also recommended culture and susceptibility testing before first-line treatment in areas with high or unknown antibiotic resistance rates.

  10. Maternal serum ratio of ghrelin to obestatin decreased in preeclampsia.

    Science.gov (United States)

    Wu, Weiguang; Fan, Xiaobin; Yu, Yuecheng; Wang, Yingchun

    2015-10-01

    Ghrelin, an endogenous for the growth hormone secretagogue receptor, has been shown to participate in blood pressure regulation. Obestatin, encoded by the same gene as ghrelin, is described as a physiological opponent of ghrelin. We hypothesized that ghrelin/obestatin imbalance played a role in the pathogenesis. This study was designed to determine the alterations of ghrelin and obestatin concentrations and ghrelin/obestatin ratio in maternal serum in preeclampsia. This retrospective case-control study included 31 preeclampsia and 31 gestational week-matched normal pregnancies. Ghrelin and obestatin concentrations in maternal serum were determined by radioimmunoassay, and the ghrelin/obestatin ratio was calculated. The ghrelin concentration and ghrelin/obestatin ratio in maternal serum were significantly lower in preeclampsia than in normal pregnancies (214.34±14.27pg/mL vs 251.49±16.15pg/mL, P=0.041, 1.07±0.09 vs 0.82±0.08, P=0.023). The obestatin concentration in maternal serum was significantly higher in preeclampsia than in normal pregnancies (276.35±15.38pg/mL vs 223.53±18.61pg/mL, P=0.019). The systolic blood pressure in preeclampsia was negatively correlated with ghrelin concentration and ghrelin/obestatin ratio (r=-0.549, P=0.003; r=-0.491, P=0.004) and was positively correlated with obestatin concentrations in preeclampsia (r=0.388, P=0.013). The findings of this study suggested disturbance of ghrelin and obestatin in maternal serum in preeclampsia, and ghrelin/obestatin imbalance might play a role in the pathogenesis of preeclampsia. Copyright © 2015 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.

  11. N-acetylcysteine prevents the development of gastritis induced by Helicobacter pylori infection.

    Science.gov (United States)

    Jang, Sungil; Bak, Eun-Jung; Cha, Jeong-Heon

    2017-05-01

    Helicobacter pylori (H. pylori) is a human gastric pathogen, causing various gastric diseases ranging from gastritis to gastric adenocarcinoma. It has been reported that combining N-acetylcysteine (NAC) with conventional antibiotic therapy increases the success rate of H. pylori eradication. We evaluated the effect of NAC itself on the growth and colonization of H. pylori, and development of gastritis, using in vitro liquid culture system and in vivo animal models. H. pylori growth was evaluated in broth culture containing NAC. The H. pylori load and histopathological scores of stomachs were measured in Mongolian gerbils infected with H. pylori strain 7.13, and fed with NAC-containing diet. In liquid culture, NAC inhibited H. pylori growth in a concentration-dependent manner. In the animal model, 3-day administration of NAC after 1 week from infection reduced the H. pylori load; 6-week administration of NAC after 1 week from infection prevented the development of gastritis and reduced H. pylori colonization. However, no reduction in the bacterial load or degree of gastritis was observed with a 6-week administration of NAC following 6-week infection period. Our results indicate that NAC may exert a beneficial effect on reduction of bacterial colonization, and prevents the development of severe inflammation, in people with initial asymptomatic or mild H. pylori infection.

  12. Horizontal versus familial transmission of Helicobacter pylori.

    Directory of Open Access Journals (Sweden)

    Sandra Schwarz

    2008-10-01

    Full Text Available Transmission of Helicobacter pylori is thought to occur mainly during childhood, and predominantly within families. However, due to the difficulty of obtaining H. pylori isolates from large population samples and to the extensive genetic diversity between isolates, the transmission and spread of H. pylori remain poorly understood. We studied the genetic relationships of H. pylori isolated from 52 individuals of two large families living in a rural community in South Africa and from 43 individuals of 11 families living in urban settings in the United Kingdom, the United States, Korea, and Colombia. A 3,406 bp multilocus sequence haplotype was determined for a total of 142 H. pylori isolates. Isolates were assigned to biogeographic populations, and recent transmission was measured as the occurrence of non-unique isolates, i.e., isolates whose sequences were identical to those of other isolates. Members of urban families were almost always infected with isolates from the biogeographic population that is common in their location. Non-unique isolates were frequent in urban families, consistent with familial transmission between parents and children or between siblings. In contrast, the diversity of H. pylori in the South African families was much more extensive, and four distinct biogeographic populations circulated in this area. Non-unique isolates were less frequent in South African families, and there was no significant correlation between kinship and similarity of H. pylori sequences. However, individuals who lived in the same household did have an increased probability of carrying the same non-unique isolates of H. pylori, independent of kinship. We conclude that patterns of spread of H. pylori under conditions of high prevalence, such as the rural South African families, differ from those in developed countries. Horizontal transmission occurs frequently between persons who do not belong to a core family, blurring the pattern of familial

  13. Helicobacter pylori as a zoonotic infection: the detection of H. pylori antigens in the milk and faeces of cows.

    Science.gov (United States)

    Safaei, Hajieh Ghasemian; Rahimi, Ebrahim; Zandi, Ashkan; Rashidipour, Alireza

    2011-02-01

    The prevalence of Helicobacter pylori infection, which may increase the risk of gastritis, peptic ulcers, and cancer, has increased worldwide. This number is estimated to be around 70-90% in developing countries and 25-50% in developed countries. It is possible that the bacterium can be transmitted via food and water as well as zoonotically and iatrogenically. Because of high prevalence of this infection in Iran, the aim of this study is to examine whether H. pylori infection might be transmitted from cow's milk and faeces. The existence of the H. pylori antibody and antigen was investigated in samples of serum, milk, and faeces from 92 lactating Holstein cows in Shahrekord, Iran. The H. pylori antigen and antibody were detected using ELISA and were confirmed by PCR. It was found that out of 92 serum specimens, 25 (27%) of the cows were positive for the H. pylori antibody and 67 specimens were negative. From these 25 seropositive cows, 10 (40%) faeces samples and four (16%) milk samples were antigen positive for H. pylori. Four of the antigen-positive milk specimens were also antigen positive for faeces. The existence of the UreC gene was also confirmed in positive samples of milk and faeces. There is a possibility that cow's milk is a transmission mode in H. pylori infection and faecal contamination and inappropriate management processes could transfer H. pylori to humans. The awareness of the H. pylori epidemiology and its method of distribution are necessary for public health measures and controlling the spread of this bacterium. Further investigation with a greater sample number is necessary to verify the ability of H. pylori transmission via milk consumption.

  14. Immunity and Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Paul Harris

    2011-03-01

    Full Text Available The bacteria called Helicobacter pylori arrived to the American continent 12,000 years ago (1, reaching South America roughly 5,400-4,600 years AC according to research by Pelayo Correa, a Colombian pathologist who found Helicobacter in stool next to Chinchorro mummies in the North of Arica close to the Pacific Ocean. In 2005, Barry Marshall was awarded the Nobel Prize for his studies on Helicobacter pylori together with Robin Warren.

  15. Ghrelin O-acyltransferase (GOAT), a specific enzyme that modifies ghrelin with a medium-chain fatty acid.

    Science.gov (United States)

    Kojima, Masayasu; Hamamoto, Akie; Sato, Takahiro

    2016-10-01

    In the gastric peptide hormone ghrelin, serine 3 (threonine 3 in frogs) is modified, primarily by n-octanoic acid; this modification is essential for ghrelin's activity. The enzyme that transfers n-octanoic acid to Ser3 of ghrelin is ghrelin O-acyltransferase (GOAT). GOAT, the only enzyme known to catalyze acyl modification of ghrelin, specifically modifies serine (or threonine) at the third position and does not modify other serine residues in ghrelin peptides. GOAT prefers n-hexanoyl-CoA over n-octanoyl-CoA as the acyl donor, although in the stomach the n-octanoyl form is the predominant form of acyl-modified ghrelin. GOAT is a promising target for drug development to treat metabolic diseases and eating disorders.

  16. Ghrelin regulates phasic dopamine and nucleus accumbens signaling evoked by food-predictive stimuli.

    Science.gov (United States)

    Cone, Jackson J; Roitman, Jamie D; Roitman, Mitchell F

    2015-06-01

    Environmental stimuli that signal food availability hold powerful sway over motivated behavior and promote feeding, in part, by activating the mesolimbic system. These food-predictive cues evoke brief (phasic) changes in nucleus accumbens (NAc) dopamine concentration and in the activity of individual NAc neurons. Phasic fluctuations in mesolimbic signaling have been directly linked to goal-directed behaviors, including behaviors elicited by food-predictive cues. Food-seeking behavior is also strongly influenced by physiological state (i.e., hunger vs. satiety). Ghrelin, a stomach hormone that crosses the blood-brain barrier, is linked to the perception of hunger and drives food intake, including intake potentiated by environmental cues. Notwithstanding, whether ghrelin regulates phasic mesolimbic signaling evoked by food-predictive stimuli is unknown. Here, rats underwent Pavlovian conditioning in which one cue predicted the delivery of rewarding food (CS+) and a second cue predicted nothing (CS-). After training, we measured the effect of ghrelin infused into the lateral ventricle (LV) on sub-second fluctuations in NAc dopamine using fast-scan cyclic voltammetry and individual NAc neuron activity using in vivo electrophysiology in separate groups of rats. LV ghrelin augmented both phasic dopamine and phasic increases in the activity of NAc neurons evoked by the CS+. Importantly, ghrelin did not affect the dopamine nor NAc neuron response to the CS-, suggesting that ghrelin selectively modulated mesolimbic signaling evoked by motivationally significant stimuli. These data demonstrate that ghrelin, a hunger signal linked to physiological state, can regulate cue-evoked mesolimbic signals that underlie food-directed behaviors. Cues that predict food availability powerfully regulate food-seeking behavior. Here we show that cue-evoked changes in both nucleus accumbens (NAc) dopamine (DA) and NAc cell activity are modulated by intra-cranial infusions of the stomach

  17. Epidemiological study on food intake and Helicobacter pylori infection.

    Science.gov (United States)

    Toyonaga, A; Okamatsu, H; Sasaki, K; Kimura, H; Saito, T; Shimizu, S; Fukuizumi, K; Tsuruta, O; Tanikawa, K; Sata, M

    2000-01-01

    We conducted an epidemiological study to investigate the relation of food intake to Helicobacter pylori (H. pylori) infection in an area endemic for H. pylori. In this study, 365 subjects, 104 men and 261 women, were randomly selected from 7,389 adult (over age 20) inhabitants of town A, Japan. The prevalence of immunoglobulin G (IgG) class antibody to H. pylori (anti-H. pylori) was 83.7% and the prevalence of anti-H. pylori increased with age significantly (P gastritis, gastroduodenal ulcer and gastric cancer tended to have a higher anti-H. pylori positive ratio (93.5%) than those without (81.0%). But there was no relationship between anti-H. pylori prevalence and sex, blood type, smoking or drinking habits. Daily intake of foods by food groups, nutrients and the concentrations of serum ingredients were compared between 37 anti-H. pylori-positive and 40 negative subjects selected from 365 inhabitants by matching up according to sex and age. The daily intake of cereals, potatoes and starches, and milks tended to be higher in positive than negative subjects, while the daily intake of algae and tea appeared to be a little higher in negative than in positive subjects. The daily zinc intake of antibody-positive subjects was significantly higher (P < 0.05) than in antibody negative subjects. On the other hand, the daily iron intake in negative subjects was significantly higher (P < 0.05) than in positive subjects. The serum concentrations of copper, zinc, and vitamin E tended to be higher in positive than negative subjects. But there were no significant differences in serum ingredients concentrations between antibody negative and positive subjects. Our findings suggest that iron and zinc intakes may effect on H. pylori infection.

  18. Helicobacter pylori impairs murine dendritic cell responses to infection.

    Directory of Open Access Journals (Sweden)

    Ya-Hui Wang

    Full Text Available BACKGROUND: Helicobacter pylori, a human pathogen associated with chronic gastritis, peptic ulcer and gastric malignancies, is generally viewed as an extracellular microorganism. Here, we show that H. pylori replicates in murine bone marrow derived-dendritic cells (BMDCs within autophagosomes. METHODOLOGY/PRINCIPAL FINDINGS: A 10-fold increase of CFU is found between 2 h and 6 h p.i. in H. pylori-infected BMDCs. Autophagy is induced around the bacterium and participates at late time points of infection for the clearance of intracellular H. pylori. As a consequence of infection, LC3, LAMP1 and MHC class II molecules are retained within the H. pylori-containing vacuoles and export of MHC class II molecules to cell surface is blocked. However, formalin-fixed H. pylori still maintain this inhibitory activity in BMDC derived from wild type mice, but not in from either TLR4 or TLR2-deficient mice, suggesting the involvement of H. pylori-LPS in this process. TNF-alpha, IL-6 and IL-10 expression was also modulated upon infection showing a TLR2-specific dependent IL-10 secretion. No IL-12 was detected favoring the hypothesis of a down modulation of DC functions during H. pylori infection. Furthermore, antigen-specific T cells proliferation was also impaired upon infection. CONCLUSIONS/SIGNIFICANCE: H. pylori can infect and replicate in BMDCs and thereby affects DC-mediated immune responses. The implication of this new finding is discussed for the biological life cycle of H. pylori in the host.

  19. Strategies used by helicobacter pylori to establish persistent infection

    Science.gov (United States)

    Abadi, Amin Talebi Bezmin

    2017-01-01

    Helicobacter pylori (H. pylori) is a Gram-negative and motile bacterium that colonizes the hostile microniche of the human stomach, then persists for the host’s entire life, if not effectively treated. Clinically, H. pylori plays a causative role in the development of a wide spectrum of diseases including chronic active gastritis, peptic ulceration, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue lymphoma. Due to the global distribution of H. pylori, it is no exaggeration to conclude that smart strategies are contributing to adaptation of the bacterium to its permanent host. Thirty-four years after the discovery of this bacterium, there are still many unanswered questions. For example, which strategies help the bacterium to survive in this inhospitable microniche? This question is slightly easier to answer if we presume the same clinical concept for both persistent infection and disease. Understanding the mechanisms governing H. pylori persistence will improve identification of the increased risk of diseases such as gastric cancer in patients infected with this bacterium. A well-defined and long-term equilibrium between the human host and H. pylori allows bacterial persistence in the gastric microniche; although this coexistence leads to a high risk of severe diseases such as gastric cancer. To escape the bactericidal activity of stomach acid, H. pylori secretes large amounts of surface-associated and cytosolic urease. The potential to avoid acidic conditions and immune evasion are discussed in order to explain the persistence of H. pylori colonization in the gastric mucosa, and data on bacterial genetic diversity are included. Information on the mechanisms related to H. pylori persistence can also provide the direction for future research concerning effective therapy and management of gastroduodenal disorders. The topics presented in the current review are important for elucidating the strategies used by H. pylori to help the bacterium