Some pharmacological effects of cinnamon and ginger herbs in obese diabetic rats

OpenAIRE

Shalaby, Mostafa Abbas; Saifan, Hamed Yahya

2014-01-01

Aims: The present study was designed to assess some pharmacological effects of cinnamon (CAE) and ginger (GAE) aqueous extracts in obese diabetic rats, and to elucidate the potential mechanisms. Materials and Methods: Forty-two Sprague-Dawley rats were randomized into 6 equal groups. Group 1 was a negative control and the other groups were rendered obese by feeding rats on high-fat diet for 4 weeks. The obese rats were subcutaneously injected with alloxan for 5*days to induce diabetes. Group ...

Some pharmacological effects of cinnamon and ginger herbs in obese diabetic rats

Science.gov (United States)

Shalaby, Mostafa Abbas; Saifan, Hamed Yahya

2014-01-01

Aims: The present study was designed to assess some pharmacological effects of cinnamon (CAE) and ginger (GAE) aqueous extracts in obese diabetic rats, and to elucidate the potential mechanisms. Materials and Methods: Forty-two Sprague-Dawley rats were randomized into 6 equal groups. Group 1 was a negative control and the other groups were rendered obese by feeding rats on high-fat diet for 4 weeks. The obese rats were subcutaneously injected with alloxan for 5*days to induce diabetes. Group 2 was a positive control, and Groups 3, 4, 5 and 6 were orally given CAE in doses 200 and 400 mg/kg and GAE in the same doses, respectively for 6 weeks. Blood samples were collected for serum biochemical analyses. Kidneys were dissected out to assay activity of tissue antioxidant enzymes: Superoxide dismutase, glutathione peroxidase and catalase. Results: CAE and GAE significantly reduced body weight and body fat mass; normalized serum levels of liver enzymes; improved lipid profile; decreased blood glucose and leptin and increased insulin serum levels in obese diabetic rats. Both extracts also increased activity of kidney antioxidant enzymes. Conclusion: CAE and GAE exhibit anti-obesity, hepatoprotective, hypolipidemic, antidiabetic and anti-oxidant effects in obese diabetic rats. These results confirm the previous reports on both extracts. The potential mechanisms underlying these effects are fully discussed and clarified. Our results affirm the traditional use of cinnamon and ginger for treating patients suffering from obesity and diabetes. The obese diabetic rat model used in this study is a novel animal model used in pharmacology researches. PMID:26401364

Leucine and protein metabolism in obese Zucker rats.

Directory of Open Access Journals (Sweden)

Pengxiang She

Full Text Available Branched-chain amino acids (BCAAs are circulating nutrient signals for protein accretion, however, they increase in obesity and elevations appear to be prognostic of diabetes. To understand the mechanisms whereby obesity affects BCAAs and protein metabolism, we employed metabolomics and measured rates of [1-(14C]-leucine metabolism, tissue-specific protein synthesis and branched-chain keto-acid (BCKA dehydrogenase complex (BCKDC activities. Male obese Zucker rats (11-weeks old had increased body weight (BW, 53%, liver (107% and fat (∼300%, but lower plantaris and gastrocnemius masses (-21-24%. Plasma BCAAs and BCKAs were elevated 45-69% and ∼100%, respectively, in obese rats. Processes facilitating these rises appeared to include increased dietary intake (23%, leucine (Leu turnover and proteolysis [35% per g fat free mass (FFM, urinary markers of proteolysis: 3-methylhistidine (183% and 4-hydroxyproline (766%] and decreased BCKDC per g kidney, heart, gastrocnemius and liver (-47-66%. A process disposing of circulating BCAAs, protein synthesis, was increased 23-29% by obesity in whole-body (FFM corrected, gastrocnemius and liver. Despite the observed decreases in BCKDC activities per gm tissue, rates of whole-body Leu oxidation in obese rats were 22% and 59% higher normalized to BW and FFM, respectively. Consistently, urinary concentrations of eight BCAA catabolism-derived acylcarnitines were also elevated. The unexpected increase in BCAA oxidation may be due to a substrate effect in liver. Supporting this idea, BCKAs were elevated more in liver (193-418% than plasma or muscle, and per g losses of hepatic BCKDC activities were completely offset by increased liver mass, in contrast to other tissues. In summary, our results indicate that plasma BCKAs may represent a more sensitive metabolic signature for obesity than BCAAs. Processes supporting elevated BCAA]BCKAs in the obese Zucker rat include increased dietary intake, Leu and protein

Effects of Obesity on Bone Mass and Quality in Ovariectomized Female Zucker Rats

Directory of Open Access Journals (Sweden)

Rafaela G. Feresin

2014-01-01

Full Text Available Obesity and osteoporosis are two chronic conditions that have been increasing in prevalence. Despite prior data supporting the positive relationship between body weight and bone mineral density (BMD, recent findings show excess body weight to be detrimental to bone mass, strength, and quality. To evaluate whether obesity would further exacerbate the effects of ovariectomy on bone, we examined the tibiae and fourth lumbar (L4 vertebrae from leptin receptor-deficient female (Leprfa/fa Zucker rats and their heterozygous lean controls (Leprfa/+ that were either sham-operated or ovariectomized (Ovx. BMD of L4 vertebra was measured using dual-energy X-ray absorptiometry, and microcomputed tomography was used to assess the microstructural properties of the tibiae. Ovariectomy significantly (P<0.001 decreased the BMD of L4 vertebrae in lean and obese Zucker rats. Lower trabecular number and greater trabecular separation (P<0.001 were also observed in the tibiae of lean- and obese-Ovx rats when compared to sham rats. However, only the obese-Ovx rats had lower trabecular thickness (Tb.Th (P<0.005 than the other groups. These findings demonstrated that ovarian hormone deficiency adversely affected bone mass and quality in lean and obese rats while obesity only affected Tb.Th in Ovx-female Zucker rats.

WNIN/GR-Ob - an insulin-resistant obese rat model from inbred WNIN strain.

Science.gov (United States)

Harishankar, N; Vajreswari, A; Giridharan, N V

2011-09-01

WNIN/GR-Ob is a mutant obese rat strain with impaired glucose tolerance (IGT) developed at the National Institute of Nutrition (NIN), Hyderabad, India, from the existing 80 year old Wistar rat (WNIN) stock colony. The data presented here pertain to its obese nature along with IGT trait as evidenced by physical, physiological and biochemical parameters. The study also explains its existence, in three phenotypes: homozygous lean (+/+), heterozygous carrier (+/-) and homozygous obese (-/-). Thirty animals (15 males and 15 females) from each phenotype (+/+, +/-, -/-) and 24 lean and obese (6 males and 6 females) rats were taken for growth and food intake studies respectively. Twelve adult rats from each phenotype were taken for body composition measurement by total body electrical conductivity (TOBEC); 12 rats of both genders from each phenotype at different ages were taken for clinical chemistry parameters. Physiological indices of insulin resistance were calculated according to the homeostasis model assessment for insulin resistance (HOMA-IR) and also by studying U¹⁴C 2-deoxy glucose uptake (2DG). WNINGR-Ob mutants had high growth, hyperphagia, polydipsia, polyurea, glycosuria, and significantly lower lean body mass, higher fat mass as compared with carrier and lean rats. These mutants, at 50 days of age displayed abnormal response to glucose load (IGT), hyperinsulinaemia, hypertriglyceridaemia, hypercholesterolaemia and hyperleptinaemia. Basal and insulin-stimulated glucose uptakes by diaphragm were significantly decreased in obese rats as compared with lean rats. Obese rats of the designated WNIN/GR-Ob strain showed obesity with IGT, as adjudged by physical, physiological and biochemical indices. These indices varied among the three phenotypes, being lowest in lean, highest in obese and intermediate in carrier phenotypes thereby suggesting that obesity is inherited as autosomal incomplete dominant trait in this strain. This mutant obese rat model is easy to

Serum Fetuin-A Levels Related with Microalbuminuria in Diet-Induced Obese Rats

Directory of Open Access Journals (Sweden)

Yanyan Li

2013-01-01

Full Text Available The aim of the study was to investigate the association between elevated serum fetuin-A and increased urine albumin excretion in obese rats, and whether increased urine albumin excretion was modified by improving hepatic steatosis and lipid metabolism disorder. Male Wistar rats 4 weeks in age were randomly divided into three groups and fed with normal chow (control group, high-fat chow (obesity group, or high-fat chow plus fenofibrate (fenofibrate group. After 24 weeks, both body weight and visceral fat/body weight ratio in obese rats were higher than in controls. A difference in serology markers and pathology associated with hepatic steatosis was also found among the three groups. Serum fetuin-A and the expression of NF-κB in the liver were increased, while serum adiponectin was decreased in obese rats in comparison to controls (. Urinary albumin/creatinine ratio (ACR was increased in the obesity group compared to controls (. The fenofibrate intervention reduced serum fetuin-A and NF-κB expression in the liver and increased serum adiponectin compared to obese rats and was accompanied by decrease in ACR. A positive correlation was found between ACR and fetuin-A (, , and a negative correlation was found between ACR and adiponectin (, . We conclude that elevated fetuin-A levels are associated with microalbuminuria in obese rats, and abnormal albuminuria is reversible by improving hepatic steatosis.

Carbenoxolone treatment ameliorated metabolic syndrome in WNIN/Ob obese rats, but induced severe fat loss and glucose intolerance in lean rats.

Directory of Open Access Journals (Sweden)

Siva Sankara Vara Prasad Sakamuri

Full Text Available BACKGROUND: 11beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1 regulates local glucocorticoid action in tissues by catalysing conversion of inactive glucocorticoids to active glucocorticoids. 11β-HSD1 inhibition ameliorates obesity and associated co-morbidities. Here, we tested the effect of 11β-HSD inhibitor, carbenoxolone (CBX on obesity and associated comorbidities in obese rats of WNIN/Ob strain, a new animal model for genetic obesity. METHODOLOGY/PRINCIPAL FINDINGS: Subcutaneous injection of CBX (50 mg/kg body weight or volume-matched vehicle was given once daily for four weeks to three month-old WNIN/Ob lean and obese rats (n = 6 for each phenotype and for each treatment. Body composition, plasma lipids and hormones were assayed. Hepatic steatosis, adipose tissue morphology, inflammation and fibrosis were also studied. Insulin resistance and glucose intolerance were determined along with tissue glycogen content. Gene expressions were determined in liver and adipose tissue. CBX significantly inhibited 11β-HSD1 activity in liver and adipose tissue of WNIN/Ob lean and obese rats. CBX significantly decreased body fat percentage, hypertriglyceridemia, hypercholesterolemia, insulin resistance in obese rats. CBX ameliorated hepatic steatosis, adipocyte hypertrophy, adipose tissue inflammation and fibrosis in obese rats. Tissue glycogen content was significantly decreased by CBX in liver and adipose tissue of obese rats. Severe fat loss and glucose- intolerance were observed in lean rats after CBX treatment. CONCLUSIONS/SIGNIFICANCE: We conclude that 11β-HSD1 inhibition by CBX decreases obesity and associated co-morbidities in WNIN/Ob obese rats. Our study supports the hypothesis that inhibition of 11β-HSD1 is a key strategy to treat metabolic syndrome. Severe fat loss and glucose -intolerance by CBX treatment in lean rats suggest that chronic 11β-HSD1 inhibition may lead to insulin resistance in normal conditions.

In vitro demonstration of anti-lipogenic activity in serum from obese rats

International Nuclear Information System (INIS)

Harris, R.B.S.; Martin, R.J.

1986-01-01

Studies with parabiosed rats provide evidence for a humoral factor, originating in obese animals, that specifically inhibits adipose lipogenesis. A bioassay was developed that allows serum from obese rats to be tested for this factor in vitro. Adipocytes are isolated from epididymal fat of 250g Sprague-Dawley rats. The cells are preincubated at 37 0 C for 1 or 12 hrs, in TC199 media containing 1.1 mg/ml glucose, 0.1 M Hepes and 2% serum. Following preincubation, the cells are washed 3 times and resuspended in serum-free media. Aliquots of cells are tested for metabolic activity in a subsequent 2 hour radiolabelled incubation in serum-free media with the addition of 0.5 μCi/ml U- 14 C-glucose. Basal, insulin (100 μU/ml) and norepinephrine (0.1 μg/ml) stimulated rates of glucose oxidation and conversion to triglyceride fatty acids are measured. Using serum from ad libitum fed rats as control, preincubation with serum from obese rats (20 days at 2 x normal intake) depressed basal and insulin stimulated glucose oxidation, and basal fatty acid synthesis. Serum from obese parabiotic rats and parabiotic partners of obese rats depressed basal fatty acid synthesis. This assay allows us to test serum for anti-lipogenic activity and may be used to identify the factor responsible for this activity in obese animals

Arginase promotes endothelial dysfunction and hypertension in obese rats.

Science.gov (United States)

Johnson, Fruzsina K; Peyton, Kelly J; Liu, Xiao-Ming; Azam, Mohammed A; Shebib, Ahmad R; Johnson, Robert A; Durante, William

2015-02-01

This study investigated whether arginase contributes to endothelial dysfunction and hypertension in obese rats. Endothelial function and arginase expression were examined in skeletal muscle arterioles from lean and obese Zucker rats (ZRs). Arginase activity, arginine bioavailability, and blood pressure were measured in lean and obese animals. Arginase activity and expression was increased while global arginine bioavailability decreased in obese ZRs. Acetylcholine or luminal flow caused dilation of isolated skeletal muscle arterioles, but this was reduced or absent in vessels from obese ZRs. Treatment of arterioles with a nitric oxide synthase inhibitor blocked dilation in lean arterioles and eliminated differences among lean and obese vessels. In contrast, arginase inhibitors or l-arginine enhanced vasodilation in obese ZRs and abolished differences between lean and obese animals, while d-arginine had no effect. Finally, mean arterial blood pressure was significantly increased in obese ZRs. However, administration of l-arginine or arginase inhibitors lowered blood pressure in obese but not lean animals, and this was associated with an improvement in systemic arginine bioavailability. Arginase promotes endothelial dysfunction and hypertension in obesity by reducing arginine bioavailability. Therapeutic approaches targeting arginase represent a promising approach in treating obesity-related vascular disease. © 2014 The Obesity Society.

Exercise training prevents the attenuation of anesthetic pre-conditioning-mediated cardioprotection in diet-induced obese rats.

Science.gov (United States)

Li, L; Meng, F; Li, N; Zhang, L; Wang, J; Wang, H; Li, D; Zhang, X; Dong, P; Chen, Y

2015-01-01

Obesity abolishes anesthetic pre-conditioning-induced cardioprotection due to impaired reactive oxygen species (ROS)-mediated adenosine monophosphate-activated protein kinase (AMPK) pathway, a consequence of increased basal myocardial oxidative stress. Exercise training has been shown to attenuate obesity-related oxidative stress. This study tests whether exercise training could normalize ROS-mediated AMPK pathway and prevent the attenuation of anesthetic pre-conditioning-induced cardioprotection in obesity. Male Sprague-Dawley rats were divided into lean rats fed with control diet and obese rats fed with high-fat diet. After 4 weeks of feeding, lean and obese rats were assigned to sedentary conditions or treadmill exercise for 8 weeks. There was no difference in infarct size between lean sedentary and obese sedentary rats after 25 min of myocardial ischemia followed by 120 min reperfusion. In lean rats, sevoflurane equally reduced infarct size in lean sedentary and lean exercise-trained rats. Molecular studies revealed that AMPK activity, endothelial nitric oxide synthase, and superoxide production measured at the end of ischemia in lean rats were increased in response to sevoflurane. In obese rats, sevoflurane increased the above molecular parameters and reduced infarct size in obese exercise-trained rats but not in obese sedentary rats. Additional study showed that obese exercise-trained rats had decreased basal oxidative stress than obese sedentary rats. The results indicate that exercise training can prevent the attenuation of anesthetic cardioprotection in obesity. Preventing the attenuation of this strategy may be associated with reduced basal oxidative stress and normalized ROS-mediated AMPK pathway, but the causal relationship remains to be determined. © 2014 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Swimming intervention mitigates HFD-induced obesity of rats through PGC-1α-irisin pathway.

Science.gov (United States)

Yang, X-Q; Yuan, H; Li, J; Fan, J-J; Jia, S-H; Kou, X-J; Chen, N

2016-05-01

Irisin, a newly discovered myokine, can drive the browning of white adipocytes to control body weight or mitigate obesity progression through regulating energy metabolism. However, the underlying mechanisms or specific signal pathways of exercise-induced irisin on the management of obesity are still unclear. Totally 30 rats were subjected to high fat diet (HFD) feeding for 8 weeks to establish the rat model with obesity successfully. HFD-induced obese model rats were provided with 8 weeks swimming intervention at moderate intensity for exploring the treatment of obesity through exercise intervention. In addition, another 15 rats were subjected to HFD feeding coupled with total 16 weeks swimming intervention at a moderate intensity from the beginning of the experiment, which was used for exploring the prevention of obesity through exercise intervention. Blood and gastrocnemius samples were harvested from obese rats after swimming intervention to explore its specific signal pathways through ELISA analysis and Western blotting. HFD feeding of rats for 8 weeks could lead to the obesity due to the disorders of lipid metabolism. Totally 8 weeks swimming intervention at moderate intensity for rats with obesity could obviously alleviate the progression of obesity and 16 weeks swimming intervention from the beginning of the experiment could significantly inhibit the development of obesity. Meanwhile, swimming intervention could result in an increased phosphorylation of AMPK and up-regulation of irisin and PGC-1α as the biomarkers of energy metabolism. Exercise intervention can activate PGC-1α-dependent irisin to induce the browning of white adipocytes, thus inhibiting or alleviating the occurrence and development of obesity.

Cold-increase in brown fat thyroxine 5'-monodeiodinase is attenuated in Zucker obese rat

International Nuclear Information System (INIS)

Wu, S.Y.; Stern, J.S.; Fisher, D.A.; Glick, Z.

1987-01-01

In this study the authors examined the possibility that the reduced brown adipose tissue (BAT) thermogenesis in the Zucker obese rat may result from a limited capacity for enzymic conversion of thyroxine (T 4 ) to triiodothyronine (T 3 ) in BAT. A total of 34 lean and obese rats, ∼4 mo old were divided into three treatment groups: group 1 (5 lean and 6 obese) was fed Purina rat chow for 21 days, and group two (5 lean and 6 obese) was fed a cafeteria diet for 21 days, and groups 3 (6 lean and 6 obese) was fed Purina rat chow and maintained in the cold (8 +/- 1 0 C) for 7 days. Activity of T 4 5'-deiodinase was determined as the rate of T 3 production from added T 4 under controlled in vitro conditions. Serum T 4 and T 3 were determined by radioimmunoassay. The rate of T 4 -to-T 3 conversion in BAT was similar in the lean and obese rats maintained at room temperature, whether fed rat chow or a cafeteria diet. However, expressed per scapular BAT depot, lean rats exposed to cold displayed about a fivefold increase in BAT T 3 production whereas only a small increase was observed in the cold-exposed obese rats. Serum T 3 levels tended to be reduced in the Zucker obese rats. The data indicate a reduced capacity for T 3 production of Zucker rat BAT exposed to cold. This defect may account for the reduced tolerance of the obese animals to cold, but it does not account for their reduced diet-induced BAT thermogenesis

Metabolic adjustments with the development, treatment, and recurrence of obesity in obesity-prone rats.

Science.gov (United States)

MacLean, Paul S; Higgins, Janine A; Johnson, Ginger C; Fleming-Elder, Brooke K; Peters, John C; Hill, James O

2004-08-01

Obesity is reaching epidemic proportions and predisposes afflicted individuals to several comorbidities. For these individuals, losing weight has proven to be an easier feat than maintaining a reduced weight. In obesity-prone rats, we examined if there is a metabolic propensity to regain weight after a period of significant weight loss. Twenty-four-hour energy expenditure (EE), sleeping metabolic rate (SMR), and nonprotein respiratory quotient (NPRQ) were obtained by indirect calorimetry with urinary nitrogen analysis and normalized to fat mass (FM) and fat-free mass (FFM) acquired by dual-energy X-ray absorptiometry. Obesity-prone rats were examined after free access to a high-fat diet for 16 wk to establish the obese state. They were again examined after 2 wk of calorie restriction, which reduced body weight (14%) and FM (32%). Rats were again examined after a further 8 wk of intake-regulated weight maintenance or ad libitum feeding that led to weight regain. Metabolic data were compared with preobese and age-matched controls. Weight loss suppressed EE and SMR beyond what was expected for the change in metabolic mass. This elevated metabolic efficiency persisted throughout weight maintenance but resolved after 8 wk of regain. Adjusted NPRQ values were elevated in weight-maintained and weight-regaining rats, suggesting a preference for carbohydrate utilization. These data support the concept that weight reduction in obesity is accompanied by metabolic adjustments beyond the drive to consume calories that predispose to weight regain, and some aspects of this adjustment persist with prolonged weight maintenance and during weight regain.

Daily Rhythms of Feeding in the Genetically Obese and Lean Zucker Rats

NARCIS (Netherlands)

Alingh Prins, Ab; Jong-Nagelsmit, Annemarie de; Keijser, Jan; Strubbe, Jan H.

1986-01-01

Feeding patterns were examined in obese (fa/fa) and lean (Fa/-) adult Zucker rats over the light-dark cycle during 14 days. Obese rats eat more than lean rats especially during the dark phase. Light and dark feeding expressed as percentage of 24 hr intake showed no significant differences between

Nicotine improves obesity and hepatic steatosis and ER stress in diet-induced obese male rats.

Science.gov (United States)

Seoane-Collazo, Patricia; Martínez de Morentin, Pablo B; Fernø, Johan; Diéguez, Carlos; Nogueiras, Rubén; López, Miguel

2014-05-01

Nicotine, the main addictive component of tobacco, promotes body weight reduction in humans and rodents. Recent evidence has suggested that nicotine acts in the central nervous system to modulate energy balance. Specifically, nicotine modulates hypothalamic AMP-activated protein kinase to decrease feeding and to increase brown adipose tissue thermogenesis through the sympathetic nervous system, leading to weight loss. Of note, most of this evidence has been obtained in animal models fed with normal diet or low-fat diet (LFD). However, its effectiveness in obese models remains elusive. Because obesity causes resistance towards many factors involved in energy homeostasis, the aim of this study has been to compare the effect of nicotine in a diet-induced obese (DIO) model, namely rats fed a high-fat diet, with rats fed a LFD. Our data show that chronic peripheral nicotine treatment reduced body weight by decreasing food intake and increasing brown adipose tissue thermogenesis in both LFD and DIO rats. This overall negative energy balance was associated to decreased activation of hypothalamic AMP-activated protein kinase in both models. Furthermore, nicotine improved serum lipid profile, decreased insulin serum levels, as well as reduced steatosis, inflammation, and endoplasmic reticulum stress in the liver of DIO rats but not in LFD rats. Overall, this evidence suggests that nicotine diminishes body weight and improves metabolic disorders linked to DIO and might offer a clear-cut strategy to develop new therapeutic approaches against obesity and its metabolic complications.

Pre-existing differences and diet-induced alterations in striatal dopamine systems of obesity-prone rats.

Science.gov (United States)

Vollbrecht, Peter J; Mabrouk, Omar S; Nelson, Andrew D; Kennedy, Robert T; Ferrario, Carrie R

2016-03-01

Interactions between pre-existing differences in mesolimbic function and neuroadaptations induced by consumption of fatty, sugary foods are thought to contribute to human obesity. This study examined basal and cocaine-induced changes in striatal neurotransmitter levels without diet manipulation and D2 /D3 dopamine receptor-mediated transmission prior to and after consumption of "junk-foods" in obesity-prone and obesity-resistant rats. Microdialysis and liquid chromatography-mass spectrometry were used to determine basal and cocaine-induced changes in neurotransmitter levels in real time with cocaine-induced locomotor activity. Sensitivity to the D2 /D3 dopamine receptor agonist quinpirole was examined before and after restricted junk-food exposure. Selectively bred obesity-prone and obesity-resistant rats were used. Cocaine-induced locomotion was greater in obesity-prone rats versus obesity-resistant rats prior to diet manipulation. Basal and cocaine-induced increases in dopamine and serotonin levels did not differ. Obesity-prone rats were more sensitive to the D2 receptor-mediated effects of quinpirole, and junk-food produced modest alterations in quinpirole sensitivity in obesity-resistant rats. These data show that mesolimbic systems differ prior to diet manipulation in susceptible versus resistant rats, and that consumption of fatty, sugary foods produce different neuroadaptations in these populations. These differences may contribute to enhanced food craving and an inability to limit food intake in susceptible individuals. © 2016 The Obesity Society.

Satiety in the obese Zucker rat: effects of carbohydrate type and acarbose (Bay g 5421).

Science.gov (United States)

Maggio, C A; Vasselli, J R

1989-09-01

Despite the obese Zucker rat's hyperphagia on carbohydrate diets such as laboratory chow, this laboratory has found that its satiety response to glucose and other simple sugars is comparable to that of its lean control rat. To further investigate carbohydrate satiety in the Zucker rat, the short-term feeding behavior of obese and lean rats was observed following intragastric infusions (7.2 kcal in 10 ml) of corn starch and the starch hydrolysates Polycose and dextrin. There were no reliable between-genotype differences in the feeding inhibitory effects of Polycose and dextrin. However, in obese rats, the satiety effect of corn starch was delayed and reduced compared to that observed in lean rats (p less than 0.04). To modify the effect of corn starch, rats were administered 0.2 or 0.6 mg/infusion of the carbohydrate digestive inhibitor acarbose (Bay g 5421). Acarbose significantly reduced the satiety effect of corn starch in lean rats (p less than 0.001), and further attenuated satiety in obese rats (p less than 0.02). Since secretion of pancreatic amylase, the enzyme that initiates starch digestion, is decreased in obese rats, this result suggests that alterations of digestive and/or absorptive processes may underlie the obese rat's impaired satiety response to complex carbohydrate.

EFFECTS OF RESVERATROL ON LIVER FUNCTION OF OBESE FEMALE WISTAR RATS

Directory of Open Access Journals (Sweden)

Nádia Araújo Miguel

2016-07-01

Full Text Available Resveratrol has antioxidant, anti-inflammatory, lipolytic, and antifibrotic properties, which may be useful in supplementation of obese patients and with liver problems. This study evaluated the effects of 6-week resveratrol supplementation on the lipid profile and liver function of female Wistar rats fed a high-fat diet to induce obesity. Sixty-four Wistar rats were divided into 4 groups (n = 16: the control group (C; the control obese group (CO; the resveratrol group (R; and the resveratrol obese group (RO. At the end of the experiment, the animals were anesthetized for blood collection and subsequent euthanasia for collection of liver biopsy. The parameters for body weight, liver weight, retroperitoneal fat weight, serum lipid and liver profiles and histopathological analysis were evaluated. The 6-week resveratrol administration did not induce weight loss nor did it reduce the lipid profile; however, it decreased the liver enzymes aspartate aminotransferase (AST and alkaline phosphatase (ALP and reduced the incidence of steatosis (75.0% in group RO compared with group CO (81.2%. Thus, we concluded that resveratrol supplementation for the short period of six weeks had a beneficial effect on liver function by reducing hepatic steatosis and the liver enzymes AST and ALP in obese female rats. Keywords: liver function; obesity; rats; resveratrol.

Weight Loss and Melatonin Reduce Obesity-Induced Oxidative Damage in Rat Testis

Directory of Open Access Journals (Sweden)

Dogan Atilgan

2013-01-01

Full Text Available Aim. We aimed to evaluate the antioxidant effects of weight loss and melatonin on the obesity-induced oxidative damage in rat testes. Materials and Methods. 28 male Wistar albino rats were randomly divided into 4 groups, each consisting of 7 rats: control group (Group 1, obesity group (Group 2, obesity + MLT group (Group 3, and weight loss group (Group 4. Rats were weighed at the beginning and at the end of the study. Bilateral orchiectomy was performed and 5 cc blood samples were obtained from all of the rats. Superoxide dismutase (SOD, malondialdehyde (MDA, and protein carbonyl (PC levels were analysed in the testicular tissues and serum. Spermatogenesis was evaluated with the Johnsen scoring system. Results. The testicular tissue and serum levels of MDA, PC, and SOD activity were increased in the obesity group in comparison to the sham operated group (P<0.05. Weight loss and melatonin treatment ameliorated MDA, PC, and SOD levels in testicular tissue and serum significantly (P<0.05. There was no significant difference between groups in terms of mean Johnsen score (P=0.727. Conclusion. Experimentally created obesity caused oxidative stress and both melatonin and weight loss reduced oxidative stress parameters in rat testes.

Vildagliptin reduces cardiac ischemic-reperfusion injury in obese orchiectomized rats.

Science.gov (United States)

Pongkan, Wanpitak; Pintana, Hiranya; Jaiwongkam, Thidarat; Kredphoo, Sasiwan; Sivasinprasasn, Sivaporn; Chattipakorn, Siriporn C; Chattipakorn, Nipon

2016-10-01

Obesity and testosterone deprivation are associated with coronary artery disease. Testosterone and vildagliptin (dipeptidyl peptidase-4 inhibitors) exert cardioprotection during ischemic-reperfusion (I/R) injury. However, the effect of these drugs on I/R heart in a testosterone-deprived, obese, insulin-resistant model is unclear. This study investigated the effects of testosterone and vildagliptin on cardiac function, arrhythmias and the infarct size in I/R heart of testosterone-deprived rats with obese insulin resistance. Orchiectomized (O) or sham operated (S) male Wistar rats were divided into 2 groups to receive normal diet (ND) or high-fat diet (HFD) for 12 weeks. Orchiectomized rats in each diet were divided to receive testosterone (2 mg/kg), vildagliptin (3 mg/kg) or the vehicle daily for 4 weeks. Then, I/R was performed by a 30-min left anterior descending coronary artery ligation, followed by a 120-min reperfusion. LV function, arrhythmia scores, infarct size and cardiac mitochondrial function were determined. HFD groups developed insulin resistance at week 12. At week 16, cardiac function was impaired in NDO, HFO and HFS rats, but was restored in all testosterone- and vildagliptin-treated rats. During I/R injury, arrhythmia scores, infarct size and cardiac mitochondrial dysfunction were prominently increased in NDO, HFO and HFS rats, compared with those in NDS rats. Treatment with either testosterone or vildagliptin similarly attenuated these impairments during I/R injury. These finding suggest that both testosterone replacement and vildagliptin share similar efficacy for cardioprotection during I/R injury by decreasing the infarct size and attenuating cardiac mitochondrial dysfunction caused by I/R injury in testosterone-deprived rats with obese insulin resistance. © 2016 Society for Endocrinology.

Effect of Octreotide on Hepatic Steatosis in Diet-Induced Obesity in Rats.

Directory of Open Access Journals (Sweden)

Mao Li

Full Text Available Non-alcoholic fatty liver disease (NAFLD caused by liver lipid dysregulation is linked to obesity. Somatostatin (SST and its analogs have been used to treat pediatric hypothalamic obesity. However, the application of such drugs for the treatment of NAFLD has not been evaluated.This study aimed to investigate the expression levels of important regulators of hepatic lipid metabolism and the possible effect of the SST analog octreotide on these regulators.SD rats were assigned to a control group and a high-fat diet group. Obese rats from the high-fat diet group were further divided into the obese and octreotide-treated groups. The body weight, plasma SST, fasting plasma glucose (FPG, insulin, triglyceride (TG, total cholesterol (TC, low-density lipoprotein cholesterol (LDL-C, high-density lipoprotein cholesterol (HDL-C and free fatty acid (FFA levels were measured. Hepatic steatosis was evaluated based on the liver TG content, HE staining and oil red O staining. The SREBP-1c, ACC1, FAS, MTP, apoB and ADRP expression levels in the liver were also determined by RT-PCR, qRT-PCR, western blot or ELISA.The obese rats induced by high-fat diet expressed more SREBP-1c, FAS and ADRP but less MTP protein in the liver than those of control rats, whereas octreotide intervention reversed these changes and increased the level of apoB protein. Compared to the control group, obese rats showed increased liver ACC1, SREBP-1c and apoB mRNA levels, whereas octreotide-treated rats showed decreased mRNA levels of apoB and SREBP-1c. This was accompanied by increased body weight, liver TG contents, FPG, TG, TC, LDL-C, FFA, insulin and derived homeostatic model assessment (HOMA values. Octreotide intervention significantly decreased these parameters. Compared to the control group, the obese group showed a decreasing trend on plasma SST levels, which were significantly increased by the octreotide intervention.Octreotide can ameliorate hepatic steatosis in obese rats

Very low-carbohydrate versus isocaloric high-carbohydrate diet in dietary obese rats.

Science.gov (United States)

Axen, Kathleen V; Axen, Kenneth

2006-08-01

The effects of a very low-carbohydrate (VLC), high-fat (HF) dietary regimen on metabolic syndrome were compared with those of an isocaloric high-carbohydrate (HC), low-fat (LF) regimen in dietary obese rats. Male Sprague-Dawley rats, made obese by 8 weeks ad libitum consumption of an HF diet, developed features of the metabolic syndrome vs. lean control (C) rats, including greater visceral, subcutaneous, and hepatic fat masses, elevated plasma cholesterol levels, impaired glucose tolerance, and fasting and post-load insulin resistance. Half of the obese rats (VLC) were then fed a popular VLC-HF diet (Weeks 9 and 10 at 5% and Weeks 11 to 14 at 15% carbohydrate), and one-half (HC) were pair-fed an HC-LF diet (Weeks 9 to 14 at 60% carbohydrate). Energy intakes of pair-fed VLC and HC rats were less than C rats throughout Weeks 9 to 14. Compared with HC rats, VLC rats exhibited impaired insulin and glycemic responses to an intraperitoneal glucose load at Week 10 and lower plasma triacylglycerol levels but retarded loss of hepatic, retroperitoneal, and total body fat at Week 14. VLC, HC, and C rats no longer differed in body weight, plasma cholesterol, glucose tolerance, or fasting insulin resistance at Week 14. Progressive decreases in fasting insulin resistance in obese groups paralleled concomitant reductions in hepatic, retroperitoneal, and total body fat. When energy intake was matched, the VLC-HF diet provided no advantage in weight loss or in improving those components of the metabolic syndrome induced by dietary obesity and may delay loss of hepatic and visceral fat as compared with an HC-LF diet.

Roselle is cardioprotective in diet-induced obesity rat model with myocardial infarction.

Science.gov (United States)

Si, Lislivia Yiang-Nee; Ali, Siti Aishah Mohd; Latip, Jalifah; Fauzi, Norsyahida Mohd; Budin, Siti Balkis; Zainalabidin, Satirah

2017-12-15

Obesity increase the risks of hypertension and myocardial infarction (MI) mediated by oxidative stress. This study was undertaken to investigate the actions of roselle aqueous extract (R) on cardiotoxicity in obese (OB) rats and thereon OB rats subjected to MI. Male Sprague-Dawley rats were fed with either normal diet or high-fat diet for 8weeks. Firstly, OB rats were divided into (1) OB and (2) OB+R (100mg/kg, p.o, 28days). Then, OB rats were subjected to MI (ISO, 85mg/kg, s.c, 2days) and divided into three groups: (1) OB+MI, (2) OB+MI+R and (3) OB+MI+enalapril for another 4weeks. Roselle ameliorated OB and OB+MI's cardiac systolic dysfunction and reduced cardiac hypertrophy and fibrosis. The increased oxidative markers and decreased antioxidant enzymes in OB and OB+MI groups were all attenuated by roselle. These observations indicate the protective effect of roselle on cardiac dysfunction in OB and OB+MI rats, which suggest its potential to be developed as a nutraceutical product for obese and obese patients with MI in the future. Copyright © 2017 Elsevier Inc. All rights reserved.

Genetic predisposition to obesity affects behavioural traits including food reward and anxiety-like behaviour in rats.

Science.gov (United States)

Vogel, Heike; Kraemer, Maria; Rabasa, Cristina; Askevik, Kaisa; Adan, Roger A H; Dickson, Suzanne L

2017-06-15

Here we sought to define behavioural traits linked to anxiety, reward, and exploration in different strains of rats commonly used in obesity research. We hypothesized that genetic variance may contribute not only to their metabolic phenotype (that is well documented) but also to the expression of these behavioural traits. Rat strains that differ in their susceptibility to develop an obese phenotype (Sprague-Dawley, Obese Prone, Obese Resistant, and Zucker rats) were exposed to a number of behavioural tests starting at the age of 8 weeks. We found a similar phenotype in the obesity susceptible models, Obese Prone and Zucker rats, with a lower locomotor activity, exploratory activity, and higher level of anxiety-like behaviour in comparison to the leaner Obese Resistant strain. We did not find evidence that rat strains with a genetic predisposition to obesity differed in their ability to experience reward from chocolate (in a condition place preference task). However, Zucker rats show higher motivated behaviour for sucrose compared to Obese Resistant rats when the effort required to obtain palatable food is relatively low. Together our data demonstrate that rat strains that differ in their genetic predisposition to develop obesity also differ in their performance in behavioural tests linked to anxiety, exploration, and reward and that these differences are independent of body weight. We conclude that genetic variations which determine body weight and the aforementioned behaviours co-exist but that future studies are required to identify whether (and which) common genes are involved. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Lean rats gained more body weight than obese ones from a high-fibre diet.

Science.gov (United States)

Li, Shaoting; Zhang, Cheng; Gu, Yingyi; Chen, Long; Ou, Shiyi; Wang, Yong; Peng, Xichun

2015-10-28

There is controversy over previous findings that a high ratio of Firmicutes to Bacteriodetes helps obese animals harvest energy from the diet. To further investigate the relationship between microbial composition and energy harvest, microbial adaptation to diet and time should be considered. In this study, lean and obese rats were successfully induced with low-fat and high-fat diets. An 8-week high soyabean fibre (HSF)-containing diet was then fed to investigate the interaction between the diet and the rats' gut microbiota, as well as their influence on rats' growth. Rats' body weight (BW) was recorded weekly; their plasma lipids and their gut microbiota at week 11, 15 and 19 were analysed. After the consumption of the HSF diet, BW of lean rats increased significantly (Pcontent of plasma cholesterol was lowered and that of TAG was upgraded in both the groups when fed the HSF diet. There was no significant difference observed at each period between lean and obese rats. In the group of lean rats, the diversity of gut microbiota was elevated strongly (Pbacterial diversity and composition in obese rats were less altered after the HSF diet control. In conclusion, the increased Firmicutes and Bacteriodetes might relate to lean rats' higher BW gain; 'obese microbiota' could not help the hosts harvest more energy from the HSF diet.

Herbal Formula HT048 Attenuates Diet-Induced Obesity by Improving Hepatic Lipid Metabolism and Insulin Resistance in Obese Rats

Directory of Open Access Journals (Sweden)

Yoon Hee Lee

2016-10-01

Full Text Available It is well established that obesity causes a variety of chronic diseases such as cardiovascular diseases and diabetes. Despite the diligent scientific efforts to find effective ways to lower the level of obesity, the size of obese population grows continuously around the world. Here we present the results that show feeding diet containing HT048, a mixture of the extracts of Crataegus pinnatifida leaves and Citrus unshiu peel, two of the well-known traditional herbal medicines in Eastern Asia, decreases obesity in rats. We fed rats with five different diets for 10 weeks: chow diet (STD, high-fat diet (HFD, high-fat diet with 0.04% orlistat, a drug to treat obesity (HFD + Orlistat, high-fat diet with 0.2% HT048 (w/w; HFD + 0.2% HT048, and high-fat diet with 0.6% HT048 (w/w; HFD + 0.6% HT048. It was found that both body and total white adipose tissue weight of HT048 groups significantly decreased compared to those of the HFD group. Moreover, HT048 decreased serum insulin levels in HFD-fed obese rats. At the molecular level, HT048 supplementation downregulated genes involved in lipogenesis, gluconeogenesis, and adipogenesis, while the expression level of β-oxidation genes was increased. Supplementation-drug interactions are not likely as HFD and HT048-containing diet did not significantly induce genes encoding CYPs. Collectively, this study suggests that HT048 taken as dietary supplement helps to decrease obesity and insulin resistance in HFD-fed obese rats.

Changes in alanine turnover rate due to nutritional and genetic obesity in the rat.

Science.gov (United States)

Yebras, M; Salvadó, J; Arola, L; Remesar, X; Segués, T

1994-08-01

The changes in alanine turnover were determined in Zucker rats, which were either genetically obese (fa/fa) or rendered obese by dietary treatment (cafeteria fed). The whole body rate of alanine turnover was higher in genetically obese rats than in rats in which obesity was induced by diet (cafeteria). This is possibly due to variations in the rate of the amino acid incorporation into proteins, since the rate of whole body alanine degradation is the same for both groups. Thus, the different pattern followed by alanine turnover rate in these types of obese animals reflects the differences in the nitrogen economy of these animals, pointing to a higher alanine utilization in the genetically obese animals and a conservative management of alanine in the cafeteria-fed animals.

LKB1-AMPK signaling in muscle from obese insulin-resistant Zucker rats and effects of training.

Science.gov (United States)

Sriwijitkamol, Apiradee; Ivy, John L; Christ-Roberts, Christine; DeFronzo, Ralph A; Mandarino, Lawrence J; Musi, Nicolas

2006-05-01

AMPK is a key regulator of fat and carbohydrate metabolism. It has been postulated that defects in AMPK signaling could be responsible for some of the metabolic abnormalities of type 2 diabetes. In this study, we examined whether insulin-resistant obese Zucker rats have abnormalities in the AMPK pathway. We compared AMPK and ACC phosphorylation and the protein content of the upstream AMPK kinase LKB1 and the AMPK-regulated transcriptional coactivator PPARgamma coactivator-1 (PGC-1) in gastrocnemius of sedentary obese Zucker rats and sedentary lean Zucker rats. We also examined whether 7 wk of exercise training on a treadmill reversed abnormalities in the AMPK pathway in obese Zucker rats. In the obese rats, AMPK phosphorylation was reduced by 45% compared with lean rats. Protein expression of the AMPK kinase LKB1 was also reduced in the muscle from obese rats by 43%. In obese rats, phosphorylation of ACC and protein expression of PGC-1alpha, two AMPK-regulated proteins, tended to be reduced by 50 (P = 0.07) and 35% (P = 0.1), respectively. There were no differences in AMPKalpha1, -alpha2, -beta1, -beta2, and -gamma3 protein content between lean and obese rats. Training caused a 1.5-fold increase in AMPKalpha1 protein content in the obese rats, although there was no effect of training on AMPK phosphorylation and the other AMPK isoforms. Furthermore, training also significantly increased LKB1 and PGC-1alpha protein content 2.8- and 2.5-fold, respectively, in the obese rats. LKB1 protein strongly correlated with hexokinase II activity (r = 0.75, P = 0.001), citrate synthase activity (r = 0.54, P = 0.02), and PGC-1alpha protein content (r = 0.81, P < 0.001). In summary, obese insulin-resistant rodents have abnormalities in the LKB1-AMPK-PGC-1 pathway in muscle, and these abnormalities can be restored by training.

Hepatic oxidative stress, genotoxicity and vascular dysfunction in lean or obese zucker rats

DEFF Research Database (Denmark)

Løhr, Mille; Folkmann, Janne Kjærsgaard; Sheykhzade, Majid

2015-01-01

Metabolic syndrome is associated with increased risk of cardiovascular disease, which could be related to oxidative stress. Here, we investigated the associations between hepatic oxidative stress and vascular function in pressurized mesenteric arteries from lean and obese Zucker rats at 14, 24 an......-generated DNA damage despite substantial hepatic steatosis.......Metabolic syndrome is associated with increased risk of cardiovascular disease, which could be related to oxidative stress. Here, we investigated the associations between hepatic oxidative stress and vascular function in pressurized mesenteric arteries from lean and obese Zucker rats at 14, 24...... and 37 weeks of age. Obese Zucker rats had more hepatic fat accumulation than their lean counterparts. Nevertheless, the obese rats had unaltered age-related level of hepatic oxidatively damaged DNA in terms of formamidopyrimidine DNA glycosylase (FPG) or human oxoguanine DNA glycosylase (hOGG1...

Cardiovascular and metabolic responses to fasting and thermoneutrality are conserved in obese Zucker rats.

Science.gov (United States)

Overton, J M; Williams, T D; Chambers, J B; Rashotte, M E

2001-04-01

The primary purpose of the study was to test the hypothesis that reduced leptin signaling is necessary to elicit the cardiovascular and metabolic responses to fasting. Lean (Fa/?; normal leptin receptor; n = 7) and obese (fa/fa; mutated leptin receptor; n = 8) Zucker rats were instrumented with telemetry transmitters and housed in metabolic chambers at 23 degrees C (12:12-h light-dark cycle) for continuous (24 h) measurement of metabolic and cardiovascular variables. Before fasting, mean arterial pressure (MAP) was higher (MAP: obese = 103 +/- 3; lean = 94 +/- 1 mmHg), whereas oxygen consumption (VO(2): obese = 16.5 +/- 0.3; lean = 18.6 +/- 0.2 ml. min(-1). kg(-0.75)) was lower in obese Zucker rats compared with their lean controls. Two days of fasting had no effect on MAP in either lean or obese Zucker rats, whereas VO(2) (obese = -3.1 +/- 0.3; lean = -2.9 +/- 0.1 ml. min(-1). kg(-0.75)) and heart rate (HR: obese = -56 +/- 4; lean = -42 +/- 4 beats/min) were decreased markedly in both groups. Fasting increased HR variability both in lean (+1.8 +/- 0.4 ms) and obese (+2.6 +/- 0.3 ms) Zucker rats. After a 6-day period of ad libitum refeeding, when all parameters had returned to near baseline levels, the cardiovascular and metabolic responses to 2 days of thermoneutrality (ambient temperature 29 degrees C) were determined. Thermoneutrality reduced VO(2) (obese = -2.4 +/- 0.2; lean = -3.3 +/- 0.2 ml. min(-1). kg(-0.75)), HR (obese = -46 +/- 5; lean = -55 +/- 4 beats/min), and MAP (obese = -13 +/- 6; lean = -10 +/- 1 mmHg) similarly in lean and obese Zucker rats. The results indicate that the cardiovascular and metabolic responses to fasting and thermoneutrality are conserved in Zucker rats and suggest that intact leptin signaling may not be requisite for the metabolic and cardiovascular responses to reduced energy intake.

Alterations of local cerebral glucose utilization in lean and obese fa/fa rats after acute adrenalectomy.

Science.gov (United States)

Doyle, P; Rohner-Jeanrenaud, F; Jeanrenaud, B

1994-08-29

An animal model often used to investigate the aetiology of obesity is the genetically obese fa/fa rat. It has many abnormalities, including hyperphagia, hyper-insulinemia, insulin resistance, low cerebral glucose utilization and an overactive hypothalamo-pituitary adrenal (HPA) axis with resulting hypercorticism. Due to the latter consideration, the aim of this work was to study the impact of acute adrenalectomy (ADX) on the local cerebral glucose utilization (LCGU) of lean and obese fa/fa rats. ADX resulted in discrete increases in LCGU of regions common to both lean and obese rats. These common regions were found to belong to be related to the limbic system. Within this system, the LCGU of the brain of obese rats was either normalized to lean sham operated values or increased by ADX to a similar degree in both groups on a percentage basis. It was concluded that the LCGU of both lean and obese animals appears to be negatively regulated, albeit to different extents, by glucocorticoids. Such negative regulation is particularly salient within the limbic system of the lean rat and even more so in the fa/fa rat. It is suggested that the long-term hypercorticism of obese fa/fa rats due to abnormal regulation of the HPA axis may result in a decreased LCGU in limbic and related regions of the brain of fa/fa rats and contribute to the expression of the obese phenotype.

The influence of sleep deprivation and obesity on DNA damage in female Zucker rats.

Science.gov (United States)

Tenorio, Neuli M; Ribeiro, Daniel A; Alvarenga, Tathiana A; Fracalossi, Ana Carolina C; Carlin, Viviane; Hirotsu, Camila; Tufik, Sergio; Andersen, Monica L

2013-01-01

The aim of this study was to evaluate overall genetic damage induced by total sleep deprivation in obese, female Zucker rats of differing ages. Lean and obese Zucker rats at 3, 6, and 15 months old were randomly distributed into two groups for each age group: home-cage control and sleep-deprived (N = 5/group). The sleep-deprived groups were deprived sleep by gentle handling for 6 hours, whereas the home-cage control group was allowed to remain undisturbed in their home-cage. At the end of the sleep deprivation period, or after an equivalent amount of time for the home-cage control groups, the rats were brought to an adjacent room and decapitated. The blood, brain, and liver tissue were collected and stored individually to evaluate DNA damage. Significant genetic damage was observed only in 15-month-old rats. Genetic damage was present in the liver cells from sleep-deprived obese rats compared with lean rats in the same condition. Sleep deprivation was associated with genetic damage in brain cells regardless of obesity status. DNA damage was observed in the peripheral blood cells regardless of sleep condition or obesity status. Taken together, these results suggest that obesity was associated with genetic damage in liver cells, whereas sleep deprivation was associated with DNA damage in brain cells. These results also indicate that there is no synergistic effect of these noxious conditions on the overall level of genetic damage. In addition, the level of DNA damage was significantly higher in 15-month-old rats compared to younger rats.

Corticosterone binding to tissues of adrenalectomized lean and obese Zucker rats.

Science.gov (United States)

Grasa, M M; Cabot, C; Balada, F; Virgili, J; Sanchis, D; Monserrat, C; Fernández-López, J A; Remesar, X; Alemany, M

1998-12-01

The binding of corticosterone, dexamethasone and aldosterone was investigated in plasma and in homogenates of liver, kidney, brain, brown adipose tissue and visceral (periovaric) and subcutaneous white adipose tissues of Zucker lean and obese rats: intact controls, adrenalectomized and sham-operated. Corticosterone-binding globulin (CBG) accounted for most of the binding, whereas that of glucocorticoid and mineralocorticoid receptors was much lower. Plasma corticosterone levels increased in sham-operated and obviously decreased in the adrenalectomized animals. Sham-operated and adrenalectomized lean rats showed decreased plasma CBG; in the obese, CBG levels were lower than in controls and were not affected by either surgery. No variation with obesity or surgery was observed either in dexamethasone or aldosterone binding, the latter being practically zero in most samples. When expressed per unit of tissue protein, CBG activity was maximal in adipose tissues, with lowest values in brain and liver. In lean rats, tissue CBG activity decreased with either surgical treatment; no changes were observed in the obese, which also had lower CBG tissue levels. The relative lack of changes in CBG of obese rats suggests that they have lost -- at least in part -- the ability to counter-modulate the changes in glucocorticoid levels through CBG modulation, thus relying only on the control of corticosterone levels. This interpretation agrees with the postulated role of CBG modulating the availability of glucocorticoids to target cells.

Panax ginseng Leaf Extracts Exert Anti-Obesity Effects in High-Fat Diet-Induced Obese Rats.

Science.gov (United States)

Lee, Seul-Gi; Lee, Yoon-Jeong; Jang, Myeong-Hwan; Kwon, Tae-Ryong; Nam, Ju-Ock

2017-09-10

Recent studies have reported that the aerial parts of ginseng contain various saponins, which have anti-oxidative, anti-inflammatory, and anti-obesity properties similar to those of ginseng root. However, the leaf extracts of Korean ginseng have not yet been investigated. In this study, we demonstrate the anti-obesity effects of green leaf and dried leaf extracts (GL and DL, respectively) of ginseng in high-fat diet (HFD)-induced obese rats. The administration of GL and DL to HFD-induced obese rats significantly decreased body weight (by 96.5% and 96.7%, respectively), and epididymal and abdominal adipose tissue mass. Furthermore, DL inhibited the adipogenesis of 3T3-L1 adipocytes through regulation of the expression of key adipogenic regulators, such as peroxisome proliferator-activated receptor (PPAR)-γ and CCAAT/enhancer-binding protein (C/EBP)-α. In contrast, GL had little effect on the adipogenesis of 3T3-L1 adipocytes but greatly increased the protein expression of PPARγ compared with that in untreated cells. These results were not consistent with an anti-obesity effect in the animal model, which suggested that the anti-obesity effect of GL in vivo resulted from specific factors released by other organs, or from increased energy expenditure. To our knowledge, these findings are the first evidence for the anti-obesity effects of the leaf extracts of Korean ginseng in vivo.

Influence of benzodiazepines on body weight and food intake in obese and lean Zucker rats.

Science.gov (United States)

Blasi, C

2000-05-01

1. The gamma-aminobutyric acid (GABA)-ergic system, which is functionally altered in obese (fa/fa) Zucker rats, plays an important role in controlling energy balance within the central nervous system. 2. GABA receptors seem to be involved in the dysfunction of the hypothalamic energy homeostasis-controlling mechanisms in these animals due to a genetically-induced defect of the leptin-neuropeptide Y system. 3. To shed further light on the possible role played by the GABA system in the pathogenesis of this rat model, two benzodiazepine (BDZ) receptor agonists (diazepam and clonazepam) and one BDZ antagonist (flumazenil) were administered intraperitoneally in obese and lean Zucker rats. 4. Body weight gain was reduced by the BDZ agonists in both phenotypes, and one receptor-agonist (diazepam) lowered insulin concentration in obese rats. In GABA-antagonist-treated obese rats, the daily amount of body weight gain and food intake acquired an oscillatory rhythm similar to that of normal rodents. 5. By demonstrating the role of BDZ receptors, these findings may help clarify the pathophysiology of obesity and insulin resistance in fatty Zucker rats.

Effects of aerobic exercise training on cardiac renin-angiotensin system in an obese Zucker rat strain.

Directory of Open Access Journals (Sweden)

Diego Lopes Mendes Barretti

Full Text Available OBJECTIVE: Obesity and renin angiotensin system (RAS hyperactivity are profoundly involved in cardiovascular diseases, however aerobic exercise training (EXT can prevent obesity and cardiac RAS activation. The study hypothesis was to investigate whether obesity and its association with EXT alter the systemic and cardiac RAS components in an obese Zucker rat strain. METHODS: THE RATS WERE DIVIDED INTO THE FOLLOWING GROUPS: Lean Zucker rats (LZR; lean Zucker rats plus EXT (LZR+EXT; obese Zucker rats (OZR and obese Zucker rats plus EXT (OZR+EXT. EXT consisted of 10 weeks of 60-min swimming sessions, 5 days/week. At the end of the training protocol heart rate (HR, systolic blood pressure (SBP, cardiac hypertrophy (CH and function, local and systemic components of RAS were evaluated. Also, systemic glucose, triglycerides, total cholesterol and its LDL and HDL fractions were measured. RESULTS: The resting HR decreased (∼12% for both LZR+EXT and OZR+EXT. However, only the LZR+EXT reached significance (p<0.05, while a tendency was found for OZR versus OZR+EXT (p = 0.07. In addition, exercise reduced (57% triglycerides and (61% LDL in the OZR+EXT. The systemic angiotensin I-converting enzyme (ACE activity did not differ regardless of obesity and EXT, however, the OZR and OZR+EXT showed (66% and (42%, respectively, less angiotensin II (Ang II plasma concentration when compared with LZR. Furthermore, the results showed that EXT in the OZR prevented increase in CH, cardiac ACE activity, Ang II and AT2 receptor caused by obesity. In addition, exercise augmented cardiac ACE2 in both training groups. CONCLUSION: Despite the unchanged ACE and lower systemic Ang II levels in obesity, the cardiac RAS was increased in OZR and EXT in obese Zucker rats reduced some of the cardiac RAS components and prevented obesity-related CH. These results show that EXT prevented the heart RAS hyperactivity and cardiac maladaptive morphological alterations in obese Zucker rats.

Modified high-sucrose diet-induced abdominally obese and normal-weight rats developed high plasma free fatty acid and insulin resistance.

Science.gov (United States)

Cao, Li; Liu, Xuehui; Cao, Hongyi; Lv, Qingguo; Tong, Nanwei

2012-01-01

Metabolically obese but normal-weight (MONW) individuals have metabolic features of overt obesity, and abdominal adiposity is common in them. Animal models of MONW individuals are lacking. We aimed to develop an abdominally obese and normal-weight (AONW) rat model. Young male Sprague-Dawley rats were fed chow or a modified high-sucrose (HS) diet for 20 weeks. The HS diet induced increased visceral adipose tissue without increased body weight, reduced glucose disposal rates, and increased hepatic glucose output during the hyperinsulinemic-euglycemic clamp, increased plasma glucose during the intraperitoneal glucose tolerance test, and increased plasma free fatty acids. Hepatic lipidosis and hepatocyte mitochondria swelling were found in HS rats through light microscopy and transmission electron microscopy; similar impairments were not observed in muscle. RT-PCR showed that mRNA expression of uncoupling protein 3 and peroxisome proliferator-activated receptor-gamma coactivator 1α increased in muscle of HS rats, while expression of mitochondrial transcription factor A, glucose transporter type 4, and insulin receptor substrate-1 did not change significantly. AONW rats developed metabolic disorders seen in MONW individuals. Steatosis, mitochondrial morphologic changes, and insulin resistance were more serious in liver than in muscle. Genes involved in fatty acid metabolism and mitochondrial function changed in less impaired muscle.

Long-term characterization of the diet-induced obese and diet-resistant rat model

DEFF Research Database (Denmark)

Madsen, Andreas Nygaard; Hansen, Gitte; Paulsen, Sarah Juel

2010-01-01

, namely the selectively bred diet-induced obese (DIO) and diet-resistant (DR) rat strains. We show that they constitute useful models of the human obesity syndrome. DIO and DR rats were fed either a high-energy (HE) or a standard chow (Chow) diet from weaning to 9 months of age. Metabolic characterization......, the results underscore the effectiveness of GLP-1 mimetics both as anti-diabetes and anti-obesity agents....

Differential responsiveness of obese (fa/fa) and lean (Fa/Fa) Zucker rats to cytokine-induced anorexia.

Science.gov (United States)

Plata-Salamán, C R; Vasselli, J R; Sonti, G

1997-01-01

Pathophysiological and pharmacological concentrations of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) in the cerebrospinal fluid (CSF) induce anorexia in normal rats. Obesity in humans and rodents is associated with increased TNF-alpha messenger RNA and protein levels in various cell types. This suggests that obese individuals may have differential regulation of cytokine production and dissimilar responsiveness to cytokines. In the present study, we investigated the effects of the intracerebroventricular (ICV) microinfusion of TNF-alpha (50, 100, and 500 ng/rat), IL-1 beta (1.0, 4.0, and 8.0 ng), and TNF-alpha (100 ng) plus IL-1 beta (1.0 ng) on obese (fa/fa) and lean (Fa/Fa) Zucker rats. The results show that: TNF-alpha and IL-1 beta, and the concomitant administration of TNF-alpha and IL-1 beta decreased the short-term (4 hours), nighttime (12 hours), and total daily food intakes in obese and lean rats; IL-1 beta was more potent relative to TNF-alpha; obese rats showed greater responsiveness to IL-1 beta: 8.0 ng IL-1 beta, for example, decreased the 12-hour food intake by 52% in obese and 22% in lean rats. On the other hand, obese and lean rats did not exhibit a significantly different responsiveness to the anorexia induced by 50, 100, or 500 ng TNF-alpha at the 4-hour period; and the concomitant ICV administration of TNF-alpha and IL-1 beta induced anorexia with additive (4-hour period) or synergistic (12-hour and 24-hour periods) effects in obese rats. The effect of TNF-alpha plus IL-1 beta in lean rats was greater than additive for the 12-hour and 24-hour periods. The difference in suppression of total daily food intake by TNF-alpha plus IL-1 beta in obese (-43%) versus lean (-23%) rats was significantly different (p < 0.01). The results show that obese (fa/fa) and lean (Fa/Fa) Zucker rats have differential responsiveness to the ICV microinfusion of two different classes of cytokines.

The influence of sleep deprivation and obesity on DNA damage in female Zucker rats

Directory of Open Access Journals (Sweden)

Neuli M. Tenorio

2013-01-01

Full Text Available OBJECTIVE: The aim of this study was to evaluate overall genetic damage induced by total sleep deprivation in obese, female Zucker rats of differing ages. METHOD: Lean and obese Zucker rats at 3, 6, and 15 months old were randomly distributed into two groups for each age group: home-cage control and sleep-deprived (N = 5/group. The sleep-deprived groups were deprived sleep by gentle handling for 6 hours, whereas the home-cage control group was allowed to remain undisturbed in their home-cage. At the end of the sleep deprivation period, or after an equivalent amount of time for the home-cage control groups, the rats were brought to an adjacent room and decapitated. The blood, brain, and liver tissue were collected and stored individually to evaluate DNA damage. RESULTS: Significant genetic damage was observed only in 15-month-old rats. Genetic damage was present in the liver cells from sleep-deprived obese rats compared with lean rats in the same condition. Sleep deprivation was associated with genetic damage in brain cells regardless of obesity status. DNA damage was observed in the peripheral blood cells regardless of sleep condition or obesity status. CONCLUSION: Taken together, these results suggest that obesity was associated with genetic damage in liver cells, whereas sleep deprivation was associated with DNA damage in brain cells. These results also indicate that there is no synergistic effect of these noxious conditions on the overall level of genetic damage. In addition, the level of DNA damage was significantly higher in 15-month-old rats compared to younger rats.

Activation of sorbitol pathway in metabolic syndrome and increased susceptibility to cataract in Wistar-Obese rats.

Science.gov (United States)

Reddy, Paduru Yadagiri; Giridharan, Nappan Veettil; Reddy, Geereddy Bhanuprakash

2012-01-01

Obesity is a major public health problem worldwide, and of late, epidemiological studies indicate a preponderance of cataracts under obesity conditions. Although cataract is a multifactorial disorder and various biochemical mechanisms have been proposed, the influence of obesity on cataractogenesis has yet to be investigated. In such a scenario, a suitable animal model that develops cataract following the onset of obesity will be a welcome tool for biomedical research. Therefore, we investigated the molecular and biochemical basis for predisposition to cataract in the obese mutant rat models established in our institute because 15%-20% of these rats develop cataracts spontaneously as they reach 12-15 months of age. We analyzed the major biochemical pathways in the normal lenses of different age groups of our obese mutant rat strains, Wistar/Obese (WNIN/Ob) and WNIN/GR-Ob, the former with euglycemia and the latter with an additional impaired glucose tolerance trait. In addition, sorbitol levels were estimated in the cataractous lenses of the obese rats. Except for the polyol pathway, all the principal pathways of the lens remained unaltered. Therefore, sorbitol levels were found to be high in the normal eye lenses of obese rats (WNIN/Ob and WNIN/GR-Ob) compared to their lean controls from three months of age onwards. Between WNIN/Ob and WNIN/GR-Ob, the levels of sorbitol were higher in the latter, suggesting a synergistic effect of impaired glucose tolerance along with obesity in the activation of the sorbitol pathway. Either way, an elevated sorbitol pathway seemed to be the predisposing factor responsible for cataract formation in these mutant rats. Activation of the sorbitol pathway indeed enhances the risk of cataract development in conditions such as metabolic syndrome. These rat models thus may be valuable tools for investigating obesity-associated cataract and for developing intervention strategies, based on these findings.

Offspring predisposition to obesity due to maternal-diet-induced obesity in rats is preventable by dietary normalization before mating.

Science.gov (United States)

Castro, Heriberto; Pomar, Catalina Amadora; Palou, Andreu; Picó, Catalina; Sánchez, Juana

2017-03-01

We studied in rats whether the expected detrimental effects in offspring associated to maternal dietary obesity may be reverted by obesogenic diet removal 1 month before mating. Female rats were fed a cafeteria diet (CD) from days 10 to 100 and then a standard diet (SD) (postcafeteria rats). One month after CD removal, postcafeteria rats and a group of SD-fed female rats (controls) were mated with males. At weaning, offspring were fed SD and followed until 4 months old. CD was effective at inducing obesity in dams. Its removal led to a reduction in body weight, although, after 30 days, rats retained excess body weight and fat than controls. During lactation, postcafeteria dams showed greater body fat, and higher leptin and adiponectin levels in milk than controls. From 2 months of life, offspring of postcafeteria dams displayed lower body weight than controls, with no differences in the percentage of fat, homeostatic model assessment for insulin resistance, or circulating parameters. Removal of CD in obese rats before gestation, although without complete reversion of body weight excess, may prevent the expected detrimental effects in offspring associated to an excess fat accumulation in adulthood and the related metabolic disturbances. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Distribution of /sup 125/I-thyroxine in different organs and tissues of dietically obese rats

Energy Technology Data Exchange (ETDEWEB)

Hartmann, K.; Voss, C.; Huebner, G. (Ernst-Moritz-Arndt-Universitaet, Greifswald (German Democratic Republic)); Weber, A. (Ernst-Moritz-Arndt-Universitaet, Greifswald (German Democratic Republic). Radiologische Klinik)

1985-04-01

The distribution of /sup 125/I-thyroxine (% dose/g tissue; tissue/plasma radioactivity ratio) was investigated in different tissues of 28-week-old obese Wistar rats. Obesity was induced by high-fat diet (HFD) and confirmed by carcass analysis; in heavy obese animals the relative and absolute fat content is increased twofold and threefold, respectively, compared to control rats fed on a low-fat diet (LFD). Heavy HFD rats exhibit diminished /sup 125/I-T/sub 4/ distribution in the 'slow pool' (fat tissue, muscle) and unchanged values in the 'fast pool' (liver, kidneys) in comparison with LFD rats with low body weight. The differences in distribution presented here are not caused by the diet per se, but they are the consequence of the obesity of the animal, because no differences in the /sup 125/I-T/sub 4/ distribution were found in the /sup 125/I-T/sub 4/ between HFD and LFD rats with relatively equal body weight and body composition. The reduced T/sub 4/ distribution in the fat tissue of obese rats is discussed in connection with possibly decreased lipolysis in this tissue and possible causal participation in the beginning of obesity.

Enhanced flavor-nutrient conditioning in obese rats on a high-fat, high-carbohydrate choice diet.

Science.gov (United States)

Wald, Hallie S; Myers, Kevin P

2015-11-01

Through flavor-nutrient conditioning rats learn to prefer and increase their intake of flavors paired with rewarding, postingestive nutritional consequences. Since obesity is linked to altered experience of food reward and to perturbations of nutrient sensing, we investigated flavor-nutrient learning in rats made obese using a high fat/high carbohydrate (HFHC) choice model of diet-induced obesity (ad libitum lard and maltodextrin solution plus standard rodent chow). Forty rats were maintained on HFHC to induce substantial weight gain, and 20 were maintained on chow only (CON). Among HFHC rats, individual differences in propensity to weight gain were studied by comparing those with the highest proportional weight gain (obesity prone, OP) to those with the lowest (obesity resistant, OR). Sensitivity to postingestive food reward was tested in a flavor-nutrient conditioning protocol. To measure initial, within-meal stimulation of flavor acceptance by post-oral nutrient sensing, first, in sessions 1-3, baseline licking was measured while rats consumed grape- or cherry-flavored saccharin accompanied by intragastric (IG) water infusion. Then, in the next three test sessions they received the opposite flavor paired with 5 ml of IG 12% glucose. Finally, after additional sessions alternating between the two flavor-infusion contingencies, preference was measured in a two-bottle choice between the flavors without IG infusions. HFHC-OP rats showed stronger initial enhancement of intake in the first glucose infusion sessions than CON or HFHC-OR rats. OP rats also most strongly preferred the glucose-paired flavor in the two-bottle choice. These differences between OP versus OR and CON rats suggest that obesity is linked to responsiveness to postoral nutrient reward, consistent with the view that flavor-nutrient learning perpetuates overeating in obesity. Copyright © 2015 Elsevier Inc. All rights reserved.

Kefir Peptides Prevent Hyperlipidemia and Obesity in High-Fat-Diet-Induced Obese Rats via Lipid Metabolism Modulation.

Science.gov (United States)

Tung, Yu-Tang; Chen, Hsiao-Ling; Wu, Hsin-Shan; Ho, Mei-Hsuan; Chong, Kowit-Yu; Chen, Chuan-Mu

2018-02-01

Obesity has reached epidemic proportions worldwide. Obesity is a complex metabolic disorder that is linked to numerous serious health complications with high morbidity. The present study evaluated the effects of kefir peptides on high fat diet (HFD)-induced obesity in rats. Kefir peptides markedly improved obesity, including body weight gain, inflammatory reactions and the formation of adipose tissue fat deposits around the epididymis and kidney, and adipocyte size. Treating high fat diet (HFD)-induced obese rats with kefir peptides significantly reduced the fatty acid synthase protein and increased the p-acetyl-CoA carboxylase protein to block lipogenesis in the livers. Kefir peptides also increased fatty acid oxidation by increasing the protein expressions of phosphorylated AMP-activated protein kinase, peroxisome proliferator-activated receptor-α, and hepatic carnitine palmitoyltransferase-1 in the livers. In addition, administration of kefir peptides significantly decreased the inflammatory response (TNF-α, IL-1β, and TGF-β) to modulate oxidative damage. These results demonstrate that kefir peptides treatment improves obesity via inhibition of lipogenesis, modulation of oxidative damage, and stimulation of lipid oxidation. Therefore, kefir peptides may act as an anti-obesity agent to prevent body fat accumulation and obesity-related metabolic diseases. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pre-existing differences in motivation for food and sensitivity to cocaine-induced locomotion in obesity-prone rats.

Science.gov (United States)

Vollbrecht, Peter J; Nobile, Cameron W; Chadderdon, Aaron M; Jutkiewicz, Emily M; Ferrario, Carrie R

2015-12-01

Obesity is a significant problem in the United States, with roughly one third of adults having a body mass index (BMI) over thirty. Recent evidence from human studies suggests that pre-existing differences in the function of mesolimbic circuits that mediate motivational processes may promote obesity and hamper weight loss. However, few preclinical studies have examined pre-existing neurobehavioral differences related to the function of mesolimbic systems in models of individual susceptibility to obesity. Here, we used selectively bred obesity-prone and obesity-resistant rats to examine 1) the effect of a novel "junk-food" diet on the development of obesity and metabolic dysfunction, 2) over-consumption of "junk-food" in a free access procedure, 3) motivation for food using instrumental procedures, and 4) cocaine-induced locomotor activity as an index of general mesolimbic function. As expected, eating a sugary, fatty, "junk-food" diet exacerbated weight gain and increased fasted insulin levels only in obesity-prone rats. In addition, obesity-prone rats continued to over-consume junk-food during discrete access testing, even when this same food was freely available in the home cage. Furthermore, when asked to press a lever to obtain food in an instrumental task, rates of responding were enhanced in obesity-prone versus obesity-resistant rats. Finally, obesity-prone rats showed a stronger locomotor response to 15 mg/kg cocaine compared to obesity-resistant rats prior to any diet manipulation. This enhanced sensitivity to this dose of cocaine is indicative of basal differences in the function of mesolimbic circuits in obesity-prone rats. We speculate that pre-existing differences in motivational systems may contribute to over-consumption and enhanced motivation in susceptible individuals. Copyright © 2015 Elsevier Inc. All rights reserved.

Pre-existing differences in motivation for food and sensitivity to cocaine-induced locomotion in obesity-prone rats

Science.gov (United States)

Vollbrecht, Peter J.; Nobile, Cameron W.; Chadderdon, Aaron M.; Jutkiewicz, Emily M.; Ferrario, Carrie R.

2015-01-01

Obesity is a significant problem in the United States, with roughly one third of adults having a body mass index (BMI) over thirty. Recent evidence from human studies suggests that pre-existing differences in the function of mesolimbic circuits that mediate motivational processes may promote obesity and hamper weight loss. However, few preclinical studies have examined pre-existing neurobehavioral differences related to the function of mesolimbic systems in models of individual susceptibility to obesity. Here, we used selectively bred obesity-prone and obesity-resistant rats to examine 1) the effect of a novel “junk-food” diet on the development of obesity and metabolic dysfunction, 2) over-consumption of “junk-food” in a free access procedure, 3) motivation for food using instrumental procedures, and 4) cocaine-induced locomotor activity as an index of general mesolimbic function. As expected, eating a sugary, fatty, “junk-food” diet exacerbated weight gain and increased fasted insulin levels only in obesity-prone rats. In addition, obesity-prone rats continued to over-consume junk-food during discrete access testing, even when this same food was freely available in the home cage. Furthermore, when asked to press a lever to obtain food in an instrumental task, rates of responding were enhanced in obesity-prone versus obesity-resistant rats. Finally, obesity-prone rats showed a stronger locomotor response to 15 mg/kg cocaine compared to obesity-resistant rats prior to any diet manipulation. This enhanced sensitivity to this dose of cocaine is indicative of basal differences in the function of mesolimbic circuits in obesity-prone rats. We speculate that pre-existing differences in motivational systems may contribute to over-consumption and enhanced motivation in susceptible individuals. PMID:26423787

Lactobacillus paracasei HII01, xylooligosaccharides, and synbiotics reduce gut disturbance in obese rats.

Science.gov (United States)

Thiennimitr, Parameth; Yasom, Sakawdaurn; Tunapong, Wannipa; Chunchai, Titikorn; Wanchai, Keerati; Pongchaidecha, Anchalee; Lungkaphin, Anusorn; Sirilun, Sasithorn; Chaiyasut, Chaiyavat; Chattipakorn, Nipon; Chattipakorn, Siriporn C

2018-03-20

The beneficial effects of pro-, pre-, and synbiotics on obesity with insulin resistance have been reported previously. However, the strain-specific effect of probiotics and the combination with various types of prebiotic fiber yield controversial outcomes and limit clinical applications. Our previous study demonstrated that the probiotic Lactobacillus paracasei (L. paracasei) HII01, prebiotic xylooligosaccharide (XOS), and synbiotics share similar efficacy in attenuating cardiac mitochondrial dysfunction in obese-insulin resistant rats. Nonetheless, the roles of HII01 and XOS on gut dysbiosis and gut inflammation under obese-insulin resistant conditions have not yet, to our knowledge, been investigated. Our hypothesis was that pro-, pre-, and synbiotics improve the metabolic parameters in obese-insulin resistant rats by reducing gut dysbiosis and gut inflammation. Male Wistar rats were fed with either a normal or high-fat diet that contained 19.77% and 59.28% energy from fat, respectively, for 12 wk. Then, the high-fat diet rats were fed daily with a 10 8 colony forming unit of the probiotic HII01, 10% prebiotic XOS, and synbiotics for 12 wk. The metabolic parameters, serum lipopolysaccharide levels, fecal Firmicutes/Bacteroidetes ratios, levels of Enterobacteriaceae, Bifidobacteria, and gut proinflammatory cytokine gene expression were quantified. The consumption of probiotic L. paracasei HII01, prebiotic XOS, and synbiotics for 12 wk led to a decrease in metabolic endotoxemia, gut dysbiosis (a reduction in the Firmicutes/Bacteroidetes ratio and Enterobacteriaceae), and gut inflammation in obese-insulin resistant rats. Pro-, pre-, and synbiotics reduced gut dysbiosis and gut inflammation, which lead to improvements in metabolic dysfunction in obese-insulin resistant rats. Copyright © 2018 Elsevier Inc. All rights reserved.

EXPERIMENTAL INVESTIGATION OF THE EFFECT ON THE CHEMERIN ADIPOKINE AND OBESITY OF PROBIOTIC USE IN OBESE RATS

Directory of Open Access Journals (Sweden)

Mensure Nur Celik

2017-06-01

Full Text Available Chemerin is a new chemotactic protein that recently joined the adipokines family. It has been shown to play a role in adipogenesis and energy metabolism, including its role on obesity, Type 2 Diabetes Mellitus (T2DM, metabolic syndrome and cardiovascular diseases. Probiotics may play role in the prevention of obesity by various mechanisms and treatment of many diseases such as T2DM. In this study, we aimed to evaluate the effects of probiotic supplementation of chemerin adipokines on serum levels and obesity markers in obese animal models. For this purpose 3 groups of experimental animals were formed. In the obtained serum samples, the effects of probiotic supplementation on chemerin and leptin level which are indicators of obesity will be examined. Weights of all the rats in the groups were weighed each week to monitor the obesity. The weight gain in the group fed with probiotic supplementation was 10,00±27,2 g for 4 weeks and the weight gain for the group fed with high fat diet was 26,200±7,085 g (p<0.05. After 8 weeks of feding the changes of BMI values of the rats were found to be statistically significant (p<0.05. There was no significant difference between the leptin values of the groups, but the difference between the mean values of the chemerin values after 12 weeks of feeding was found to be statistically significant (p <0.05. As a result; this study showed that obese rats reduced the weight gain of probiotic supplementation without calorie restriction, positive effects on BMI and chemerin adipokine serum levels.

Insulin binding to brain capillaries is reduced in genetically obese, hyperinsulinemic Zucker rats

International Nuclear Information System (INIS)

Schwartz, M.W.; Figlewicz, D.F.; Kahn, S.E.; Baskin, D.G.; Greenwood, M.R.; Porte, D. Jr.

1990-01-01

In order to study the role of plasma insulin in regulating the binding of insulin to the endothelium of the blood-brain barrier (BBB), insulin binding to a purified preparation of brain capillaries was measured in both genetically obese Zucker rats and lean Zucker controls. We found a reduction of 65% in brain capillary insulin binding site number in the obese compared to lean rats with no change in receptor affinity. Furthermore, specific insulin binding to brain capillaries was negatively correlated (p less than 0.05) to the plasma insulin level, suggesting a role for plasma insulin in regulating insulin binding. A similar relationship was observed between insulin receptor number in liver membranes and the plasma insulin level. We conclude that obese, hyperinsulinemic Zucker rats exhibit a reduction in the number of BBB insulin receptors, which parallels the reduction seen in other peripheral tissues. Since insulin receptors have been hypothesized to participate in the transport of insulin across the BBB, the reduction observed in the obese rats may account for the decrease in cerebrospinal fluid insulin uptake previously demonstrated in these animals

Modified High-Sucrose Diet-Induced Abdominally Obese and Normal-Weight Rats Developed High Plasma Free Fatty Acid and Insulin Resistance

Directory of Open Access Journals (Sweden)

Li Cao

2012-01-01

Full Text Available Introduction. Metabolically obese but normal-weight (MONW individuals have metabolic features of overt obesity, and abdominal adiposity is common in them. Animal models of MONW individuals are lacking. We aimed to develop an abdominally obese and normal-weight (AONW rat model. Methods and Results. Young male Sprague-Dawley rats were fed chow or a modified high-sucrose (HS diet for 20 weeks. The HS diet induced increased visceral adipose tissue without increased body weight, reduced glucose disposal rates, and increased hepatic glucose output during the hyperinsulinemic-euglycemic clamp, increased plasma glucose during the intraperitoneal glucose tolerance test, and increased plasma free fatty acids. Hepatic lipidosis and hepatocyte mitochondria swelling were found in HS rats through light microscopy and transmission electron microscopy; similar impairments were not observed in muscle. RT-PCR showed that mRNA expression of uncoupling protein 3 and peroxisome proliferator-activated receptor-gamma coactivator 1α increased in muscle of HS rats, while expression of mitochondrial transcription factor A, glucose transporter type 4, and insulin receptor substrate-1 did not change significantly. Conclusion. AONW rats developed metabolic disorders seen in MONW individuals. Steatosis, mitochondrial morphologic changes, and insulin resistance were more serious in liver than in muscle. Genes involved in fatty acid metabolism and mitochondrial function changed in less impaired muscle.

Impulsive-choice patterns for food in genetically lean and obese Zucker rats.

Science.gov (United States)

Boomhower, Steven R; Rasmussen, Erin B; Doherty, Tiffany S

2013-03-15

Behavioral-economic studies have shown that differences between lean and obese Zuckers in food consumption depend on the response requirement for food. Since a response requirement inherently increases the delay to reinforcement, differences in sensitivity to delay may also be a relevant mechanism of food consumption in the obese Zucker rat. Furthermore, the endocannabinoid neurotransmitter system has been implicated in impulsivity, but studies that attempt to characterize the effects of cannabinoid drugs (e.g., rimonabant) on impulsive choice may be limited by floor effects. The present study aimed to characterize impulsive-choice patterns for sucrose using an adjusting-delay procedure in genetically lean and obese Zuckers. Ten lean and ten obese Zucker rats chose between one lever that resulted in one pellet after a standard delay (either 1 s or 5 s) and a second lever that resulted in two or three pellets after an adjusting delay. After behavior stabilized under baseline, rimonabant (0-10 mg/kg) was administered prior to some choice sessions in the two-pellet condition. Under baseline, obese Zuckers made more impulsive choices than leans in three of the four standard-delay/pellet conditions. Additionally, in the 2-pellet condition, rimonabant increased impulsive choice in lean rats in the 1-s standard-delay condition; however, rimonabant decreased impulsive choice in obese rats in the 1-s and 5-s standard-delay conditions. These data suggest that genetic factors that influence impulsive choice are stronger in some choice conditions than others, and that the endocannabinoid system may be a relevant neuromechanism. Copyright © 2012 Elsevier B.V. All rights reserved.

Antiobesity, antioxidant and antidiabetic activities of red Ginseng plant extract in obese diabetic rats

Directory of Open Access Journals (Sweden)

Mostafa Abbas Shalaby

2013-06-01

Full Text Available Aim: This study aimed to investigate the effects of red ginseng extract (RGE on adiposity index, some serum biochemical parameters and tissue antioxidant activity in obese diabetic rats. Materials and Methods: Five groups of male Sprague-Dawley rats were used. Group (1 was negative control and the other 4 groups were fed on high fat-diet for 6 weeks to induce obesity. The obese rats were then rendered diabetic by intraperitoneal injection of alloxan for 5 days. Group (2 was kept obese diabetic (positive control and the other 3 groups were orally given RGE at 100, 200 and 400 mg /kg /day, respectively, for 4 weeks. Blood samples were collected for biochemical analyses and kidneys were taken to assay of activities of antioxidant enzymes. Results: oral dosage of RGE to obese diabetic rats significantly (P < 0.05 reduced adiposity index; decreased serum levels of aspartate aminotransferase (AST, alanine aminotransferase (ALT, gamma- glutamyl transpeptidase (GGT enzymes, total cholesterol (TC, triglycerides (TG, and low density lipoproteins (LDL-c and improved atherogenic index. Blood glucose and leptin hormone decreased, but insulin increased by administration of RGE. it increased activities of superoxide dismutase (SOD, glutathione peroxidase (GPx and catalase (CAT antioxidant enzymes in kidneys tissues. Conclusion: Red ginseng extract produces antiobesity, antioxidant, and antidiabetic activities in obese diabetic rats. The study suggests that red ginseng plant may be beneficial for the treatment of patients who suffer from obesity associated with diabetes. [J Intercult Ethnopharmacol 2013; 2(3.000: 165-172

Treatment with low-dose resveratrol reverses cardiac impairment in obese prone but not in obese resistant rats.

Science.gov (United States)

Louis, Xavier L; Thandapilly, Sijo J; MohanKumar, Suresh K; Yu, Liping; Taylor, Carla G; Zahradka, Peter; Netticadan, Thomas

2012-09-01

We hypothesized that a low-dose resveratrol will reverse cardiovascular abnormalities in rats fed a high-fat (HF) diet. Obese prone (OP) and obese resistant (OR) rats were fed an HF diet for 17 weeks; Sprague-Dawley rats fed laboratory chow served as control animals. During the last 5 weeks of study, treatment group received resveratrol daily by oral gavage at a dosage of 2.5 mg/kg body weight. Assessments included echocardiography, blood pressure, adiposity, glycemia, insulinemia, lipidemia, and inflammatory and oxidative stress markers. Body weight and adiposity were significantly higher in OP rats when compared to OR rats. Echocardiographic measurements showed prolonged isovolumic relaxation time in HF-fed OP and OR rats. Treatment with resveratrol significantly improved diastolic function in OP but not in OR rats without affecting adiposity. OP and OR rats had increased blood pressure which remained unchanged with treatment. OP rats had elevated fasting serum glucose and insulin, whereas OR rats had increased serum glucose and normal insulin concentrations. Resveratrol treatment significantly reduced serum glucose while increasing serum insulin in both OP and OR rats. Inflammatory and oxidative stress markers, serum triglycerides and low-density lipoprotein were higher in OP rats, which were significantly reduced with treatment. In conclusion, HF induced cardiac dysfunction in both OP and OR rats. Treatment reversed abnormalities in diastolic heart function associated with HF feeding in OP rats, but not in OR rats. The beneficial effects of resveratrol may be mediated through regression of hyperglycemia, oxidative stress and inflammation. Copyright © 2012 Elsevier Inc. All rights reserved.

Obesity does not aggravate osteoporosis or osteoblastic insulin resistance in orchiectomized rats.

Science.gov (United States)

Potikanond, Saranyapin; Rattanachote, Pinyada; Pintana, Hiranya; Suntornsaratoon, Panan; Charoenphandhu, Narattaphol; Chattipakorn, Nipon; Chattipakorn, Siriporn

2016-02-01

The present study aimed to test the hypothesis that testosterone deprivation impairs osteoblastic insulin signaling, decreases osteoblast survival, reduces bone density, and that obesity aggravates those deleterious effects in testosterone-deprived rats. Twenty four male Wistar rats underwent either a bilateral orchiectomy (O, n=12) or a sham operation (S, n=12). Then the rats in each group were further divided into two subgroups fed with either a normal diet (ND) or a high-fat diet (HF) for 12 weeks. At the end of the protocol, blood samples were collected to determine metabolic parameters and osteocalcin ratios. The tibiae were collected to determine bone mass using microcomputed tomography and for osteoblast isolation. The results showed that rats fed with HF (sham-operated HF-fed rats (HFS) and ORX HF-fed rats (HFO)) developed peripheral insulin resistance and had decreased trabecular bone density. In ND-fed rats, only the ORX ND-fed rats (NDO) group had decreased trabecular bone density. In addition, osteoblastic insulin resistance, as indicated by a decrease in tyrosine phosphorylation of the insulin receptor and Akt, were observed in all groups except the sham-operated ND-fed rats (NDS) rats. Those groups, again with the exception of the NDS rats, also had decreased osteoblastic survival. No differences in the levels of osteoblastic insulin resistance and osteoblastic survival were found among the NDO, HFS, and HFO groups. These findings suggest that either testosterone deprivation or obesity alone can impair osteoblastic insulin signaling and decrease osteoblastic survival leading to the development of osteoporosis. However, obesity does not aggravate those deleterious effects in the bone of testosterone-deprived rats. © 2016 Society for Endocrinology.

Prevention of diet-induced obesity in rats by oral application of collagen fragments

Directory of Open Access Journals (Sweden)

Raksha Nataliia G.

2018-01-01

Full Text Available The aim of the present study was to determine whether orally applied collagen fragments (CFs could affect the development of obesity in obese rats. To this end, experimental rats that were exposed to a high-calorie diet (HCD for four weeks were randomly divided into two groups: HCD and HCD+CFs, with both groups continuing to receive the HCD. However, rats from the HCD+CFs group were also provided with CFs in a 0.05-M citrate buffer (pH 5.0 (1 g·kg-1 of body weight by intragastric administration, every other day for the next six weeks. Selected parameters associated with obesity development and insulin resistance, as well as serum markers of oxidative stress and the cytokine profile were assessed at the end of the 10th week. Supplementation with CFs resulted in a decrease in body weight and body mass index when compared to animals exposed to a HCD. The observed changes were assumed to be caused by a lower food intake and increased water intake by obese rats treated with CFs. Enhanced activity of superoxide dismutase (SOD, catalase (CAT and decreased malondialdehyde (MDA concentration were detected in the HCD+CF group of animals when compared to untreated HCD-fed rats. Administration of CFs also lowered the serum concentrations of the proinflammatory cytokines IL-1β and IL-12, whereas the concentration of the anti-inflammatory cytokine IL-10 was significantly increased and the concentration of cytokine IL-4 was near the control value. Decreased concentrations of fasting blood glucose, glycated hemoglobin (GHbA1c and serum insulin and increased tolerance to glucose in the oral glucose tolerance test (OGTT were observed in the HCD+CF group of animals when compared to rats in the HCD group. We concluded that CFs mediated a therapeutic effect on obesity development in rats exposed to a HCD by affecting pathways involved in obesity pathogenesis.

Four-Week Consumption of Malaysian Honey Reduces Excess Weight Gain and Improves Obesity-Related Parameters in High Fat Diet Induced Obese Rats

Directory of Open Access Journals (Sweden)

Suhana Samat

2017-01-01

Full Text Available Many studies revealed the potential of honey consumption in controlling obesity. However, no study has been conducted using Malaysian honey. In this study, we investigated the efficacy of two local Malaysian honey types: Gelam and Acacia honey in reducing excess weight gain and other parameters related to obesity. The quality of both honey types was determined through physicochemical analysis and contents of phenolic and flavonoid. Male Sprague-Dawley rats were induced to become obese using high fat diet (HFD prior to introduction with/without honey or orlistat for four weeks. Significant reductions in excess weight gain and adiposity index were observed in rats fed with Gelam honey compared to HFD rats. Moreover, levels of plasma glucose, triglycerides, and cholesterol, plasma leptin and resistin, liver enzymes, renal function test, and relative organ weight in Gelam and Acacia honey treated groups were reduced significantly when compared to rats fed with HFD only. Similar results were also displayed in rats treated with orlistat, but with hepatotoxicity effects. In conclusion, consumption of honey can be used to control obesity by regulating lipid metabolism and appears to be more effective than orlistat.

Four-Week Consumption of Malaysian Honey Reduces Excess Weight Gain and Improves Obesity-Related Parameters in High Fat Diet Induced Obese Rats.

Science.gov (United States)

Samat, Suhana; Kanyan Enchang, Francis; Nor Hussein, Fuzina; Wan Ismail, Wan Iryani

2017-01-01

Many studies revealed the potential of honey consumption in controlling obesity. However, no study has been conducted using Malaysian honey. In this study, we investigated the efficacy of two local Malaysian honey types: Gelam and Acacia honey in reducing excess weight gain and other parameters related to obesity. The quality of both honey types was determined through physicochemical analysis and contents of phenolic and flavonoid. Male Sprague-Dawley rats were induced to become obese using high fat diet (HFD) prior to introduction with/without honey or orlistat for four weeks. Significant reductions in excess weight gain and adiposity index were observed in rats fed with Gelam honey compared to HFD rats. Moreover, levels of plasma glucose, triglycerides, and cholesterol, plasma leptin and resistin, liver enzymes, renal function test, and relative organ weight in Gelam and Acacia honey treated groups were reduced significantly when compared to rats fed with HFD only. Similar results were also displayed in rats treated with orlistat, but with hepatotoxicity effects. In conclusion, consumption of honey can be used to control obesity by regulating lipid metabolism and appears to be more effective than orlistat.

Obesity decreases the oxidant stress induced by tobacco smoke in a rat model.

Science.gov (United States)

Montaño, Martha; Pérez-Ramos, J; Esquivel, A; Rivera-Rosales, R; González-Avila, G; Becerril, C; Checa, M; Ramos, C

2016-09-01

Obesity and emphysema are associated with low-grade systemic inflammation and oxidant stress. Assuming that the oxidant stress induced by emphysema would be decreased by obesity, we analyzed the oxidant/antioxidant state in a rat model combining both diseases simultaneously. Obesity was induced using sucrose, while emphysema by exposure to tobacco smoke. End-points evaluated were: body weight, abdominal fat, plasma dyslipidemia and malondialdehyde (MDA), insulin and glucose AUC, activities of Mn-superoxide dismutase (Mn-SOD), glutathione reductase (GR), glutathione transferase (GST) and glutathione peroxidase (GPx); lung MnSOD and 3-nitrotyrosine (3-NT) immunostaining, and expression of αV and β6 integrin subunits. In rats with obesity, the body weight, abdominal fat, plasma triglyceride levels, glucose AUC, insulin levels, GST activity, and αV and β6 integrin expressions were amplified. The rats with emphysema had lower values of body weight, abdominal fat, plasma insulin, triglycerides and glucose AUC but higher values of plasma MDA, GPx activity, and the lung expression of the αV and β6 integrins. The combination of obesity and emphysema compared to either condition alone led to diminished body weight, abdominal fat, plasma insulin MDA levels, GPx and GST activities, and αV and β6 integrin expressions; these parameters were all previously increased by obesity. Immunostaining for MnSOD augmented in all experimental groups, but the staining for 3-NT only increased in rats treated with tobacco alone or combined with sucrose. Results showed that obesity reduces oxidant stress and integrin expression, increasing antioxidant enzyme activities; these changes seem to partly contribute to a protective mechanism of obesity against emphysema development.

Effects of 2-AG on the reinforcing properties of wheel activity in obese and lean Zucker rats.

Science.gov (United States)

Smith, Shilo L; Rasmussen, Erin B

2010-07-01

The endocannabinoid system plays a role in obesity, primarily by its role in food reward. Activity, also involved in obesity, seems to be at least partially controlled by the endocannabinoid system, but the relevant behavioral and neurochemical mechanisms have not been well established. This study represents an attempt to begin elucidating these mechanisms by examining the effects of an endogenous cannabinoid ligand, 2-arachidonoylglycerol (2-AG), on the reinforcing properties of exercise reinforcement in lean and obese Zucker rats. Ten obese and 10 lean Zucker rats pressed a locked door under a progressive ratio schedule of reinforcement that, when unlocked, provided access to a running wheel for 2-min periods. After baseline breakpoints were established, doses of 2-AG (0.3-3 mg/kg) were administered before experimental sessions. Obese rats exhibited lower breakpoints for wheel activity, lower response rates, and fewer revolutions compared with lean rats. 2-AG decreased breakpoints, response rates, and revolutions for obese rats, and revolutions only for lean rats. These data suggest that 2-AG may reduce the reinforcing properties of activity, and that obese Zuckers may show a greater sensitivity to 2-AG. The data also suggest that endocannabinoids may play a role in the reinforcing properties of exercise.

Eucommia leaf extract (ELE) prevents OVX-induced osteoporosis and obesity in rats.

Science.gov (United States)

Zhang, Wenping; Fujikawa, Takahiko; Mizuno, Kaito; Ishida, Torao; Ooi, Kazuya; Hirata, Tetsuya; Wada, Atsunori

2012-01-01

The cortex of Eucommia ulmoides Oliver is widely used to treat kidney deficiency in traditional Chinese medicine. Its leaves have recently been reported to have anti-obesity properties in metabolic syndrome-like rat models. Due to a sharp decline in estrogen production, obesity, together with osteoporosis, are common problems in postmenopausal women. In this study, we examined the potential effect of Eucommia leaf extract (ELE) in preventing osteoporosis and obesity induced by ovariectomy (OVX). Forty-six female Wistar rats were divided into six groups: Sham-Cont, OVX-Cont, and four OVX groups administered estradiol and different concentrations of ELE 1.25%, ELE 2.5%, and ELE 5%. Treatments were administered after ovariectomy at six weeks of age and continued for 12 weeks. OVX induced a significant decrease in the bone mineral density (BMD) of the lumbar, femora, and tibiae, together with a marked increase in body mass index (BMI). The administration of 5% ELE led to a significant increase in tibial and femoral BMD, as well as significantly increased bone-strength parameters when compared with OVX-Cont rats. According to the suppressed Dpd and increased osteocalcin concentrations in ELE 5% rats, we suggest that varying proportions of bone formation and bone absorption contributed to the enhanced BMD in the femora and tibiae. In addition, significant decreases in body weight, BMI and fat tissue in 5% ELE rats were also observed. These results suggest that ELE may have curative properties for BMD and BMI in OVX rats, and could provide an alternative therapy for the prevention of both postmenopausal osteoporosis and obesity.

Increased in vivo glucose utilization in 30-day-old obese Zucker rat: Role of white adipose tissue

International Nuclear Information System (INIS)

Krief, S.; Bazin, R.; Dupuy, F.; Lavau, M.

1988-01-01

In vivo whole-body glucose utilization and uptake in multiple individual tissues were investigated in conscious 30-day-old Zucker rats, which when obese are hyperphagic, hyperinsulinemic, and normoglycemic. Whole-body glucose metabolism (assessed by [3- 3 H]glucose) was 40% higher in obese (fa/fa) than in lean (Fa/fa) rats, suggesting that obese rats were quite responsive to their hyperinsulinemia. In obese compared with lean rats, tissue glucose uptake was increased by 15, 12, and 6 times in dorsal, inguinal, perigonadal white depots, respectively; multiplied by 2.5 in brown adipose tissue; increased by 50% in skin from inguinal region but not in that from cranial, thoracic, or dorsal area; and increased twofold in diaphragm but similar in heart in proximal intestine, and in total muscular mass of limbs. The data establish that in young obese rats the hypertrophied white adipose tissue was a major glucose-utilizing tissue whose capacity for glucose disposal compared with that of half the muscular mass. Adipose tissue could therefore play an important role in the homeostasis of glucose in obese rats in the face of their increased carbohydrate intake

Activity of thyroxine 5' deiodinase in brown fat of lean and obese zucker rats

International Nuclear Information System (INIS)

Wu, S.Y.; Fisher, D.A.; Stern, J.S.; Glick, Z.

1986-01-01

This study examines the possibility that the reduced brown adipose tissue (BAT) thermogenesis in the Zucker obese rat may result from a limited capacity for conversion of T 4 to T 3 in BAT, through activity of T 4 5' deiodinase. Eighteen lean (Fa/.) and 18 age matched obese (fa/fa), about 16 weeks old, were each divided into 3 groups (n=6 per group). Group 1 and 2 were fed Purina Rat Chow and a cafeteria diet respectively for 21 days, and maintained at 22 0 C+/-2. Group 3 was fed rat chow and maintained at 8 0 C+/-1 for 7 days. Activity of T 4 5'deiodinase was determined in vitro. T 3 was measured by a radioimmunoassay. The rate of T 4 to T 3 conversion was similar in the lean and the obese rats maintained at room temperature, whether fed rat chow or a cafeteria diet (about 40 to 50 pmol T 3 /scapular BAT depot, per hour). However, lean rats exposed to the cold displayed about a 5 fold increase in T 4 5' deiodinase activity (p 3 may account for the reduced tolerance of obese animals to cold, but it does not account for their reduced diet induced BAT thermogenesis

Sibutramine reduces feeding, body fat and improves insulin resistance in dietary-obese male Wistar rats independently of hypothalamic neuropeptide Y

Science.gov (United States)

Brown, Michael; Bing, Chen; King, Peter; Pickavance, Lucy; Heal, David; Wilding, John

2001-01-01

We studied the effects of the novel noradrenaline and serotonin (5-HT) reuptake inhibitor sibutramine on feeding and body weight in a rat model of dietary obesity, and whether it interacts with hypothalamic neuropeptide Y (NPY) neurones.Chow-fed and dietary-obese (DIO) male Wistar rats were given sibutramine (3 mg kg−1 day−1 p.o.) or deionized water for 21 days.Sibutramine decreased food intake throughout the treatment period in both dietary-obese rats (Psibutramine-treated dietary-obese rats (Psibutramine treatment (Psibutramine compared to untreated controls.The hypophagic and anti-obesity effects of sibutramine in dietary-obese Wistar rats appear not to be mediated by inhibition of ARC NPY neurones. PMID:11309262

Milk improved the metabolic syndrome in obese ß rats

Directory of Open Access Journals (Sweden)

María Catalina Olguin

2014-02-01

Full Text Available The response of adult spontaneously obese rats from the IIMb/Beta strain fed a high calcium skimmed milk diet (MHCa, high calcium from carbonate (HCa and a normal AIN 93 diet during 45 days was evaluated. Body weight, food intake and fecal fat excretion were measured. At the end of the experiment rats were euthanized, abdominal fat pads and livers were excised and weighed. Blood and liver triacylglycerols, total cholesterol and fractions were quantified. Body weight increase and abdominal fat pads in the MHCa group were significantly lower than in the other two. Plasma triacylglycerols, total and LDL-cholesterol were diminished in the MHCa group. Fecal lipid excretion was increased in the adult MHCa group. Total liver lipids and triacylglycerols showed a significant diminution in the MHCa group. These results suggest that calcium and other bioactive compounds from milk, most probably present in whey fraction, and not calcium carbonate exerted an "anti-obesity" effect on these rats.

Cereal based diets modulate some markers of oxidative stress and inflammation in lean and obese Zucker rats

Directory of Open Access Journals (Sweden)

Mano Mark

2011-05-01

Full Text Available Abstract Background The potential of cereals with high antioxidant capacity for reducing oxidative stress and inflammation in obesity is unknown. This study investigated the impact of wheat bran, barley or a control diet (α-cellulose on the development of oxidative stress and inflammation in lean and obese Zucker rats. Methods Seven wk old, lean and obese male Zucker rats (n = 8/group were fed diets that contained wheat bran, barley or α-cellulose (control. After 3 months on these diets, systolic blood pressure was measured and plasma was analysed for glucose, insulin, lipids, oxygen radical absorbance capacity (ORAC, malondialdehyde, glutathione peroxidase and adipokine concentration (leptin, adiponectin, interleukin (IL-1β, IL-6, TNFα, plasminogen activator inhibitor (PAI-1, monocyte chemotactic protein (MCP-1. Adipokine secretion rates from visceral and subcutaneous adipose tissue explants were also determined. Results Obese rats had higher body weight, systolic blood pressure and fasting blood lipids, glucose, insulin, leptin and IL-1β in comparison to lean rats, and these measures were not reduced by consumption of wheat bran or barley based diets. Serum ORAC tended to be higher in obese rats fed wheat bran and barley in comparison to control (p = 0.06. Obese rats had higher plasma malondialdehyde (p Conclusions A 3-month dietary intervention was sufficient for Zucker obese rats to develop oxidative stress and systemic inflammation. Cereal-based diets with moderate and high antioxidant capacity elicited modest improvements in indices of oxidative stress and inflammation.

Moderately Low Magnesium Intake Impairs Growth of Lean Body Mass in Obese-Prone and Obese-Resistant Rats Fed a High-Energy Diet

Directory of Open Access Journals (Sweden)

Jesse Bertinato

2016-04-01

Full Text Available The physical and biochemical changes resulting from moderately low magnesium (Mg intake are not fully understood. Obesity and associated co-morbidities affect Mg metabolism and may exacerbate Mg deficiency and physiological effects. Male rats selectively bred for diet-induced obesity (OP, obese-prone or resistance (OR, obese-resistant were fed a high-fat, high-energy diet containing moderately low (LMg, 0.116 ± 0.001 g/kg or normal (NMg, 0.516 ± 0.007 g/kg Mg for 13 weeks. The growth, body composition, mineral homeostasis, bone development, and glucose metabolism of the rats were examined. OP and OR rats showed differences (p < 0.05 in many physical and biochemical measures regardless of diet. OP and OR rats fed the LMg diet had decreased body weight, lean body mass, decreased femoral size (width, weight, and volume, and serum Mg and potassium concentrations compared to rats fed the NMg diet. The LMg diet increased serum calcium (Ca concentration in both rat strains with a concomitant decrease in serum parathyroid hormone concentration only in the OR strain. In the femur, Mg concentration was reduced, whereas concentrations of Ca and sodium were increased in both strains fed the LMg diet. Plasma glucose and insulin concentrations in an oral glucose tolerance test were similar in rats fed the LMg or NMg diets. These results show that a moderately low Mg diet impairs the growth of lean body mass and alters femoral geometry and mineral metabolism in OP and OR rats fed a high-energy diet.

Vagotomy ameliorates islet morphofunction and body metabolic homeostasis in MSG-obese rats

International Nuclear Information System (INIS)

Lubaczeuski, C.; Balbo, S.L.; Ribeiro, R.A.; Vettorazzi, J.F.; Santos-Silva, J.C.; Carneiro, E.M.; Bonfleur, M.L.

2015-01-01

The parasympathetic nervous system is important for β-cell secretion and mass regulation. Here, we characterized involvement of the vagus nerve in pancreatic β-cell morphofunctional regulation and body nutrient homeostasis in 90-day-old monosodium glutamate (MSG)-obese rats. Male newborn Wistar rats received MSG (4 g/kg body weight) or saline [control (CTL) group] during the first 5 days of life. At 30 days of age, both groups of rats were submitted to sham-surgery (CTL and MSG groups) or subdiaphragmatic vagotomy (Cvag and Mvag groups). The 90-day-old MSG rats presented obesity, hyperinsulinemia, insulin resistance, and hypertriglyceridemia. Their pancreatic islets hypersecreted insulin in response to glucose but did not increase insulin release upon carbachol (Cch) stimulus, despite a higher intracellular Ca 2+ mobilization. Furthermore, while the pancreas weight was 34% lower in MSG rats, no alteration in islet and β-cell mass was observed. However, in the MSG pancreas, increases of 51% and 55% were observed in the total islet and β-cell area/pancreas section, respectively. Also, the β-cell number per β-cell area was 19% higher in MSG rat pancreas than in CTL pancreas. Vagotomy prevented obesity, reducing 25% of body fat stores and ameliorated glucose homeostasis in Mvag rats. Mvag islets demonstrated partially reduced insulin secretion in response to 11.1 mM glucose and presented normalization of Cch-induced Ca 2+ mobilization and insulin release. All morphometric parameters were similar among Mvag and CTL rat pancreases. Therefore, the higher insulin release in MSG rats was associated with greater β-cell/islet numbers and not due to hypertrophy. Vagotomy improved whole body nutrient homeostasis and endocrine pancreatic morphofunction in Mvag rats

Activation of the NLRP3 inflammasome induces vascular dysfunction in obese OLETF rats

International Nuclear Information System (INIS)

Liu, Penghao; Xie, Qihai; Wei, Tong; Chen, Yichen; Chen, Hong; Shen, Weili

2015-01-01

Objective: Obesity-induced vascular dysfunction is related to chronic low-grade systemic inflammation. Recent studies indicate that NLRP3, a multiprotein complex formed by NOD-like receptor (NLR) family members, is a key component mediating internal sterile inflammation, but the role in obesity-related vascular dysfunction is largely unknown. In the present study, we investigate whether NLRP3 activation is involved in vascular inflammation in obese Otsuka Long-Evans Tokushima Fatty rats (OLETF). Methods and results: Male OLETF with their control Long-Evans Tokushima Otsuka rats (LETO) were studied at 3 and 12 months of age. Aortic relaxation in response to acetylcholine decreased gradually with age in both strains, with early and persistent endothelium dysfunction in obese OLETF compared with age-matched LETO controls. These changes are associated with parallel changes of aortic endothelial nitric oxide synthase (eNOS) content, macrophage accumulation and intimal thickening. NLRP3 increased in OLETF rats compared to LETO. Consistent with inflammasome activation, the conversion of procaspase-1 to cleaved and activated forms as well as IL-1β markedly increased in OLETF rats. Additionally, we observed increased expression of dynamin-related protein-1 (Drp1) and decreased fusion-relative protein optic atropy-1(OPA1). Altered mitochondrial dynamics was associated with elevated oxidative stress level in OLETF aortas. Conclusions: These results demonstrate that obesity seems to accelerate endothelial dysfunction in OLETFs via the activation of NLRP3 and mitochondrial dysfunction. - Highlights: • NLRP3 is involved in obesity-induced vascular dysfunction. • Impaired mitochondrial dynamics may have been linked to mitochondrial defect and inflammasome activation. • Obesity seems to accelerate vascular dysfunction via NLRP3 activation and mitochondrial dysfunction.

Activation of the NLRP3 inflammasome induces vascular dysfunction in obese OLETF rats

Energy Technology Data Exchange (ETDEWEB)

Liu, Penghao [State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension and Department of Hypertension, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Xie, Qihai [Department of Cardiology, Shanghai Jiading District Central Hospital, Shanghai (China); Wei, Tong [State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension and Department of Hypertension, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Chen, Yichen [Department of Pharmacology, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Chen, Hong, E-mail: hchen100@shsmu.edu.cn [Department of Pharmacology, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Shen, Weili, E-mail: wlshen@sibs.ac.cn [State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension and Department of Hypertension, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China)

2015-12-04

Objective: Obesity-induced vascular dysfunction is related to chronic low-grade systemic inflammation. Recent studies indicate that NLRP3, a multiprotein complex formed by NOD-like receptor (NLR) family members, is a key component mediating internal sterile inflammation, but the role in obesity-related vascular dysfunction is largely unknown. In the present study, we investigate whether NLRP3 activation is involved in vascular inflammation in obese Otsuka Long-Evans Tokushima Fatty rats (OLETF). Methods and results: Male OLETF with their control Long-Evans Tokushima Otsuka rats (LETO) were studied at 3 and 12 months of age. Aortic relaxation in response to acetylcholine decreased gradually with age in both strains, with early and persistent endothelium dysfunction in obese OLETF compared with age-matched LETO controls. These changes are associated with parallel changes of aortic endothelial nitric oxide synthase (eNOS) content, macrophage accumulation and intimal thickening. NLRP3 increased in OLETF rats compared to LETO. Consistent with inflammasome activation, the conversion of procaspase-1 to cleaved and activated forms as well as IL-1β markedly increased in OLETF rats. Additionally, we observed increased expression of dynamin-related protein-1 (Drp1) and decreased fusion-relative protein optic atropy-1(OPA1). Altered mitochondrial dynamics was associated with elevated oxidative stress level in OLETF aortas. Conclusions: These results demonstrate that obesity seems to accelerate endothelial dysfunction in OLETFs via the activation of NLRP3 and mitochondrial dysfunction. - Highlights: • NLRP3 is involved in obesity-induced vascular dysfunction. • Impaired mitochondrial dynamics may have been linked to mitochondrial defect and inflammasome activation. • Obesity seems to accelerate vascular dysfunction via NLRP3 activation and mitochondrial dysfunction.

Dietary salt restriction improves cardiac and adipose tissue pathology independently of obesity in a rat model of metabolic syndrome.

Science.gov (United States)

Hattori, Takuya; Murase, Tamayo; Takatsu, Miwa; Nagasawa, Kai; Matsuura, Natsumi; Watanabe, Shogo; Murohara, Toyoaki; Nagata, Kohzo

2014-12-02

Metabolic syndrome (MetS) enhances salt sensitivity of blood pressure and is an important risk factor for cardiovascular disease. The effects of dietary salt restriction on cardiac pathology associated with metabolic syndrome remain unclear. We investigated whether dietary salt restriction might ameliorate cardiac injury in DahlS.Z-Lepr(fa)/Lepr(fa) (DS/obese) rats, which are derived from a cross between Dahl salt-sensitive and Zucker rats and represent a model of metabolic syndrome. DS/obese rats were fed a normal-salt (0.36% NaCl in chow) or low-salt (0.0466% NaCl in chow) diet from 9 weeks of age and were compared with similarly treated homozygous lean littermates (DahlS.Z-Lepr(+)/Lepr(+), or DS/lean rats). DS/obese rats fed the normal-salt diet progressively developed hypertension and showed left ventricular hypertrophy, fibrosis, and diastolic dysfunction at 15 weeks. Dietary salt restriction attenuated all of these changes in DS/obese rats. The levels of cardiac oxidative stress and inflammation and the expression of cardiac renin-angiotensin-aldosterone system genes were increased in DS/obese rats fed the normal-salt diet, and dietary salt restriction downregulated these parameters in both DS/obese and DS/lean rats. In addition, dietary salt restriction attenuated the increase in visceral adipose tissue inflammation and the decrease in insulin signaling apparent in DS/obese rats without reducing body weight or visceral adipocyte size. Dietary salt restriction did not alter fasting serum glucose levels but it markedly decreased the fasting serum insulin concentration in DS/obese rats. Dietary salt restriction not only prevents hypertension and cardiac injury but also ameliorates insulin resistance, without reducing obesity, in this model of metabolic syndrome. © 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

The Cooccurrence of Obesity, Osteoporosis, and Sarcopenia in the Ovariectomized Rat: A Study for Modeling Osteosarcopenic Obesity in Rodents.

Science.gov (United States)

Ezzat-Zadeh, Zahra; Kim, Jeong-Su; Chase, P Bryant; Arjmandi, Bahram H

2017-01-01

Obesity, osteoporosis, and sarcopenia may individually occur due to age-related gradual alterations in body composition. This study investigates the cooccurrence of these age-related diseases in female animals with low levels of ovarian hormone in the absence of complex multifactorial process of chronological aging. Thirty-six 5- and 10-month-old female rats were chosen to model pre- and postmenopausal women, respectively. Rats were divided into three treatment groups in each age category-sham, ovariectomized (ovx), and ovx + E 2 (17 β -estradiol, 10  μ g/kg)-and were pair-fed. Volunteer wheel running activity, body composition, bone microstructure, serum C-telopeptides of type I collagen, bone specific alkaline phosphatase, E 2 , and gastrocnemius and soleus muscles were analyzed. The cooccurrence of osteoporosis, sarcopenia, and obesity was observed in the older ovx rats associated with a significant ( p obesity and body composition translational research in females without the confounding effect of genetic background.

Differential Effect of Electroacupuncture on Inflammatory Adipokines in Two Rat Models of Obesity

Directory of Open Access Journals (Sweden)

Jacqueline J.T. Liaw

2016-08-01

Full Text Available Chronic inflammation is known to be associated with visceral obesity and insulin resistance which are characterized by altered levels of production of pro- and anti-inflammatory adipokines. The dysregulation of the production of inflammatory adipokines and their functions in obese individuals leads to a state of chronic low-grade inflammation and may promote obesity-linked metabolic disorders and cardiovascular diseases such as insulin resistance, metabolic syndrome, and atherosclerosis. Electroacupuncture (EA was tested to see if there was a difference in its effect on pro- and anti-inflammatory adipokine levels in the blood serum and the white adipose tissue of obese Zucker fatty rats and high-fat diet-induced obese Long Evans rats. In the two rat models of obesity, on Day 12 of treatment, repeated applications of EA were seen to have had a significant differential effect for serum tumor necrosis factor-α, adiponectin, the adiponectin:leptin ratio, and blood glucose. For the adipose tissue, there was a differential effect for adiponectin that was on the borderline of significance. To explore these changes further and how they might affect insulin resistance would require a modification to the research design to use larger group sizes for the two models or to give a greater number of EA treatments.

Anti obese potential of Cucurbita maxima seeds oil: effect on lipid profile and histoarchitecture in high fat diet induced obese rats.

Science.gov (United States)

Kalaivani, A; Sathibabu Uddandrao, V V; Brahmanaidu, P; Saravanan, Ganapathy; Nivedha, P R; Tamilmani, P; Swapna, K; Vadivukkarasi, Sasikumar

2017-10-19

In this study, we made an attempt to evaluate the potential of Cucurbita maxima seeds oil (CSO) against high-fat diet (HFD)-induced obesity in rats. We investigated the effect of CSO (100 mg/kg body weight) supplementation over 30 days on the changes of HFD-induced obese rats in body weight, biochemical parameters and lipid profile as well as investigated the effects of CSO on the histopathological changes. Oral administration with CSO revealed significant diminution in body weight gain, glucose and insulin levels, which altered the activity of lipid profile and restored the pathological alterations. It demonstrated that CSO had considerably altered these parameters when evaluated with HFD control rats. In conclusion, this study established that CSO prevents the HFD-induced obesity by altering the markers important to lipid metabolism.

Cardiac β-adrenergic responsiveness of obese Zucker rats: The role of AMPK.

Science.gov (United States)

Bussey, Carol T; Thaung, Hp Aye; Hughes, Gillian; Bahn, Andrew; Lamberts, Regis R

2018-06-05

What is the central question of the study? What is the main finding and its importance? 1. Is the reduced signalling of AMPK, a key regulator of energy homeostasis in the heart, responsible for the reduced β-adrenergic responsiveness of the heart in obesity? 2. Inhibition of AMPK in isolated hearts prevented the reduced cardiac β-adrenergic responsiveness of obese rats, which was accompanied by reduced phosphorylation of AMPK, a proxy of AMPK activity. This suggests a direct functional link between β-adrenergic responsiveness and AMPK signalling in the heart, and that AMPK might be an important target to restore the β-adrenergic responsiveness in the heart in obesity. The obesity epidemic impacts heavily on cardiovascular health, in part due to changes in cardiac metabolism. AMP-activated protein kinase (AMPK) is a key regulator of energy homeostasis in the heart, and is regulated by β-adrenoceptors (AR) under normal conditions. In obesity, chronic sympathetic overactivation leads to impaired cardiac β-AR responsiveness, although it is unclear whether AMPK signalling, downstream of β-AR, contributes to this dysfunction. Therefore, we aimed to determine whether reduced AMPK signalling is responsible for the reduced β-AR responsiveness in obesity. In isolated hearts of lean and obese Zucker rats, we tested β-AR responsiveness to β 1 -AR agonist isoproterenol (ISO, 1 × 10 -10 - 5 × 10 -8  M) in the absence and presence of the AMPK inhibitor compound C (CC, 10 μM). β 1 -AR expression and AMPK phosphorylation were assessed by Western blot. β-Adrenergic responsiveness was reduced in the hearts of obese rats (LogEC50 of ISO-developed pressure dose-response curves: lean -8.53 ± 0.13 vs. obese -8.35 ± 0.10 10 x M; p  0.05, n = 6 per group). β 1 -AR expression and AMPK phosphorylation were reduced in hearts of obese rats (AMPK at Thr 172 : lean 1.73 ± 0.17 vs. lean CC 0.81 ± 0.13, and obese 1.18 ± 0.09 vs. obese CC 0.81 ± 0

Dietary D-psicose reduced visceral fat mass in high-fat diet-induced obese rats.

Science.gov (United States)

Chung, Young-Mee; Hyun Lee, Joo; Youl Kim, Deuk; Hwang, Se-Hee; Hong, Young-Ho; Kim, Seong-Bo; Jin Lee, Song; Hye Park, Chi

2012-02-01

D-Psicose, a C-3 epimer of D-fructose, has shown promise in reducing body fat accumulation in normal rats and plasma glucose level in genetic diabetic mice. Effects of D-psicose on diet-induced obesity are not clearly elucidated, and we investigated food intake, body weight, and fat accumulation in rats fed high-fat (HF) diet. Sprague-Dawley rats became obese by feeding HF diet for 4 wk, and were assigned either to normal or HF diet supplemented with or without D-psicose, sucrose, or erythritol for 8 wk. Changing HF to normal diet gained less body weight and adipose tissue due to different energy intake. D-psicose-fed rats exhibited lower weight gain, food efficiency ratio, and fat accumulation than erythritol- and sucrose-fed rats. This effect was more prominent in D-psicose-fed rats with normal diet than with HF diet, suggesting combination of psicose and calorie restriction further reduced obesity. There was no difference in serum cholesterol/high-density lipoprotein (HDL)-C and low-density lipoprotein (LDL)-C/HDL-C ratios between D-psicose group and other groups. Liver weight in 5% psicose group with normal diet was higher than in other groups, but histopathological examination did not reveal any psicose-related change. D-Psicose inhibited the differentiation of mesenchymal stem cell (MSC) to adipose tissue in a concentration-dependent manner. These results demonstrate that D-psicose produces a marked decrease, greater than erythritol, in weight gain and visceral fat in an established obesity model by inhibiting MSC differentiation to adipocyte. Thus, D-psicose can be useful in preventing and reducing obesity as a sugar substitute and food ingredient. We can develop D-psicose as a sugar substitute and food ingredient since it can prevent obesity in normal people, but also suppress adiposity as a sugar substitute or food ingredients with antiobesity effect in obese people. D-psicose can be unique functional sweetener because of its function of reducing visceral

[Effects of octreotide on fatty infiltration of the pancreas in high-fat diet induced obesity rats].

Science.gov (United States)

Yu, Tao; Liu, Rui; Li, Mao; Li, Xian; Qiang, Ou; Huang, Wei; Tang, Chengwei

2014-03-01

To investigate effects of octreotide on fatty infiltration of the pancreas in high-fat diet induced obesity rats. SD rats were divided into control group (n = 14) and high-fat diet group (n = 36). Obese rats from the high-fat diet group were further divided into 2 groups: the obese group (n = 14) and the octreotide-treated group (n = 16). Rats in the octreotide-treated group were subcutaneously injected with octreotide per 12 h (40 mg/kg BW) for 8 days. Body weight, fasting plasma glucose (FPG), fasting serum insulin, triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) levels, pancreatic TG and FFA content were measured. Homeostatic model assessment (HOMA) index was calculated. Somatostatin (SST) and the expression of adipose differentiation-related protein (ADFP) in pancrea were measured. Pathological changes of pancreas were examined with light microscopy. Body weight, Lee's index, FPG, fasting serum insulin, TG, TC levels and HOMA index in the obese group were higher than those in the control group (P pancreas, and lowering the levels of plasma glucose and lipid in the high-fat diet induced obesity rats.

Down-regulation of hypothalamic pro-opiomelanocortin (POMC) expression after weaning is associated with hyperphagia-induced obesity in JCR rats overexpressing neuropeptide Y.

Science.gov (United States)

Diané, Abdoulaye; Pierce, W David; Russell, James C; Heth, C Donald; Vine, Donna F; Richard, Denis; Proctor, Spencer D

2014-03-14

We hypothesised that hypothalamic feeding-related neuropeptides are differentially expressed in obese-prone and lean-prone rats and trigger overeating-induced obesity. To test this hypothesis, in the present study, we measured energy balance and hypothalamic neuropeptide Y (NPY) and pro-opiomelanocortin (POMC) mRNA expressions in male JCR:LA-cp rats. We compared, in independent cohorts, free-feeding obese-prone (Obese-FF) and lean-prone (Lean-FF) rats at pre-weaning (10 d old), weaning (21-25 d old) and early adulthood (8-12 weeks). A group of Obese-pair-feeding (PF) rats pair-fed to the Lean-FF rats was included in the adult cohort. The body weights of 10-d-old Obese-FF and Lean-FF pups were not significantly different. However, when the pups were shifted from dams' milk to solid food (weaning), the obese-prone rats exhibited more energy intake over the days than the lean-prone rats and higher body and fat pad weights and fasting plasma glucose, leptin, insulin and lipid levels. These differences were consistent with higher energy consumption and lower energy expenditure. In the young adult cohort, the differences between the Obese-FF and Lean-FF rats became more pronounced, yielding significant age effects on most of the parameters of the metabolic syndrome, which were reduced in the Obese-PF rats. The obese-prone rats displayed higher NPY expression than the lean-prone rats at pre-weaning and weaning, and the expression levels did not differ by age. In contrast, POMC expression exhibited significant age-by-genotype differences. At pre-weaning, there was no genotype difference in POMC expression, but in the weanling cohort, obese-prone pups exhibited lower POMC expression than the lean-prone rats. This genotype difference became more pronounced at adulthood. Overall, the development of hyperphagia-induced obesity in obese-prone JCR rats is related to POMC expression down-regulation in the presence of established NPY overexpression.

Vagotomy ameliorates islet morphofunction and body metabolic homeostasis in MSG-obese rats

Energy Technology Data Exchange (ETDEWEB)

Lubaczeuski, C.; Balbo, S.L. [Laboratório de Fisiologia Endócrina e Metabolismo, Centro de Ciências Biológicas e da Saúde, Universidade Estadual do Oeste do Paraná, Cascavel, PR (Brazil); Ribeiro, R.A. [Universidade Federal do Rio de Janeiro, Macaé, RJ (Brazil); Vettorazzi, J.F.; Santos-Silva, J.C.; Carneiro, E.M. [Laboratório de Pâncreas Endócrino e Metabolismo, Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP (Brazil); Bonfleur, M.L. [Laboratório de Fisiologia Endócrina e Metabolismo, Centro de Ciências Biológicas e da Saúde, Universidade Estadual do Oeste do Paraná, Cascavel, PR (Brazil)

2015-02-24

The parasympathetic nervous system is important for β-cell secretion and mass regulation. Here, we characterized involvement of the vagus nerve in pancreatic β-cell morphofunctional regulation and body nutrient homeostasis in 90-day-old monosodium glutamate (MSG)-obese rats. Male newborn Wistar rats received MSG (4 g/kg body weight) or saline [control (CTL) group] during the first 5 days of life. At 30 days of age, both groups of rats were submitted to sham-surgery (CTL and MSG groups) or subdiaphragmatic vagotomy (Cvag and Mvag groups). The 90-day-old MSG rats presented obesity, hyperinsulinemia, insulin resistance, and hypertriglyceridemia. Their pancreatic islets hypersecreted insulin in response to glucose but did not increase insulin release upon carbachol (Cch) stimulus, despite a higher intracellular Ca{sup 2+} mobilization. Furthermore, while the pancreas weight was 34% lower in MSG rats, no alteration in islet and β-cell mass was observed. However, in the MSG pancreas, increases of 51% and 55% were observed in the total islet and β-cell area/pancreas section, respectively. Also, the β-cell number per β-cell area was 19% higher in MSG rat pancreas than in CTL pancreas. Vagotomy prevented obesity, reducing 25% of body fat stores and ameliorated glucose homeostasis in Mvag rats. Mvag islets demonstrated partially reduced insulin secretion in response to 11.1 mM glucose and presented normalization of Cch-induced Ca{sup 2+} mobilization and insulin release. All morphometric parameters were similar among Mvag and CTL rat pancreases. Therefore, the higher insulin release in MSG rats was associated with greater β-cell/islet numbers and not due to hypertrophy. Vagotomy improved whole body nutrient homeostasis and endocrine pancreatic morphofunction in Mvag rats.

Different natriuretic responses in obese and lean rats in response to nitric oxide reduction.

Science.gov (United States)

Ambrozewicz, Marta A; Khraibi, Ali A; Simsek-Duran, Fatma; DeBose, Sophia C; Baydoun, Hind A; Dobrian, Anca D

2011-08-01

Nitric oxide (NO) is an important regulator of renal sodium transport and participates in the control of natriuresis and diuresis. In obesity, the nitric oxide bioavailability was reportedly reduced, which may contribute to the maintenance of hypertension. The aim of this study was to determine the effect of NO depletion on renal sodium handling in a model of diet-induced obesity hypertension. Obese hypertensive (obesity-prone (OP)) and lean normotensive (obesity-resistant (OR)) Sprague-Dawley rats were treated with 1.2 mg/kg/day N(G)-nitro-L-arginine-methyl ester (L-NAME) for 4 weeks to inhibit NO synthesis. Acute pressure natriuresis and diuresis were measured in response to an increase in perfusion pressure. NHE3 and Na(+), K(+)-ATPase protein expression were measured by Western blot and NHE3 activity was determined as the rate of pH change in brush border membrane vesicles. NHE3 membrane localization was determined by confocal microscopy. L-NAME did not significantly attenuate the natriuretic and diuretic responses to increases in renal perfusion pressure (RPP) in OP rats while inducing a significant reduction in OR rats. Following chronic NO inhibition, NHE3 protein expression and activity and Na(+), K(+)-ATPase protein expression were significantly increased in the OR but not in the OP group. Immunofluorescence studies indicated that the increase in NHE3 activity could be, at least in part, due to NHE3 membrane trafficking. Obese hypertensive rats have a weaker natriuretic response in response to NO inhibition compared to lean rats and the mechanism involves different regulation of the apical sodium exchanger NHE3 expression, activity, and trafficking.

Effect of soy protein on obesity-linked renal and pancreatic disorders in female rats

International Nuclear Information System (INIS)

Osman, H.F.; El-Sherbiny, E.M.

2006-01-01

The purpose of this study was to identify the effect of soy protein based diet on renal and pancreatic disorders in female obese rats. Animals assigned into group I in which 30 rats fed on a balanced diet. Group II contained 30 rats fed on a diet containing 30% fats for 4 weeks. At the end of the 4 th week, one-half of each group was treated as group III which contain 15 rats (half of group I) fed on diet containing 25% soy protein for 3 weeks and represents soy protein group, and the other half served as control. Group IV contained 15 rats (half of group II) fed on a diet containing 25% soy protein for 3 weeks and served as obese + soy protein group, and the other half fed on a normal balanced diet for 3 weeks and represents the obese group. Body weights of rats were recorded every week during the experimental period. Renal and pancreatic functions were measured as urea, creatinine, glomerular filtration rate (creatinine clearance), ammonia, sodium and potassium ions, total protein, albumin, globulin, glucose, insulin and alpha-amylase activity. Feeding with soy protein led to a very high significant increase in urea while creatinine was significantly decreased and creatinine clearance was significantly increased in the groups fed on soy protein. Ammonia concentration was increased in all groups and there was non-significant alteration in sodium and potassium ion concentrations. In soy protein groups (groups III and IV), total protein, albumin and globulin levels were increased. Glucose level was increased in obese rats and significantly decreased in groups III and IV. In group IV, insulin level was decreased which implicated to insulin excess in obesity. Soy protein decreased alpha-amylase activity in groups III and IV as compared to control rats. From these results, soy protein have a direct and protective effect on glomerular disorders and pancreatic secretions. This may be due to isoflavone contents in soy which can modulate the disturbance in metabolism

Ephedra-Treated Donor-Derived Gut Microbiota Transplantation Ameliorates High Fat Diet-Induced Obesity in Rats.

Science.gov (United States)

Wang, Jing-Hua; Kim, Bong-Soo; Han, Kyungsun; Kim, Hojun

2017-05-23

Changes in gut microbiota (GM) are closely associated with metabolic syndrome, obesity, type 2 diabetes and so on. Several medicinal herbs, including Ephedra sinica (Es), have anti-obesity effects that ameliorate metabolic disorders. Therefore, in this study we evaluated whether Es maintains its anti-obesity effect through Es-altered gut microbiota (EsM) transplantation. GM was isolated from cecal contents of Es treated and untreated rats following repeated transplants into obese rats via oral gavage over three weeks. High-fat-diet (HFD)-induced obese rats transplanted with EsM lost significant body weight, epididymal fat, and perirenal fat weight, but no remarkable changes were observed in abdominal fat, liver, cecum weight and food efficiency ratio. In addition, treatment with EsM also significantly lowered the fasting blood glucose, serum insulin level, and insulin resistance index. Meanwhile, EsM transplantation significantly reduced gene expression of proinflammatory cytokines interleukin-1 and monocyte chemotactic protein-1. Rats treated with EsM also showed changed GM composition, especially blautia, roseburia and clostridium, significantly reduced the level of endotoxin and markedly increased the acetic acid in feces. Overall, our results demonstrated that EsM ameliorates HFD-induced obesity and related metabolic disorders, like hyperglycemia and insulin resistance, and is strongly associated with modulating the distribution of GM, enterogenous endotoxin and enteral acetic acid.

Obesity and the use of antibiotics and probiotics in rats.

Science.gov (United States)

de Sá Del Fiol, Fernando; Tardelli Ferreira, Alessandra Cristina Marciano; Marciano, Jorge José; Marques, Maria Claudia; Sant'Ana, Luciane Lopes

2014-01-01

Obesity has become a major public health challenge in recent years. Recent studies suggest that alterations of the gut microbiota by antibiotics could play an important role in obesity. We investigated this topic using 60 Wistar rats, which were divided into 3 experimental groups: rats treated with amoxicillin, rats treated with amoxicillin plus Saccharomyces boulardii and controls. Treatments were administered over the course of 2 weeks. Tetrapolar bioelectric impedance analysis and anthropometric evaluations were conducted. The body mass index was significantly lower for the animals in the control group (p = 0.034). The same result was observed for the Lee index: the control group had a lower index than the 2 groups that received antibiotic treatment (p = 0.0019). The total body water data demonstrated that the control group had the greatest amount of body water (279.1 g, p = 0.0243). The groups treated with the antibiotic exhibited a greater accumulation of body fat than the control group.

Modulation of olfactory sensitivity and glucose sensing by the feeding state in obese Zucker rats.

Directory of Open Access Journals (Sweden)

Pascaline eAimé

2014-09-01

Full Text Available The Zucker fa/fa rat has been widely used as an animal model to study obesity, since it recapitulates most of its behavioral and metabolic dysfunctions, such as hyperphagia, hyperglycemia and insulin resistance. Although it is well established that olfaction is under nutritional and hormonal influences, little is known about the impact of metabolic dysfunctions on olfactory performances and glucose-sensing in the olfactory system of the obese Zucker rat. In the present study, using a behavioral paradigm based on a conditioned olfactory aversion, we have shown that both obese and lean Zucker rats have a better olfactory sensitivity when they are fasted than when they are satiated. Interestingly, the obese Zucker rats displayed a higher olfactory sensitivity than their lean controls. By investigating the molecular mechanisms involved in glucose-sensing in the olfactory system, we demonstrated that sodium-coupled glucose transporters 1 (SGLT1 and insulin dependent glucose transporters 4 (GLUT4 are both expressed in the olfactory bulb (OB. By comparing the expression of GLUT4 and SGLT1 in OB of obese and lean Zucker rats, we found that only SGLT1 is regulated in genotype-dependent manner. Next, we used glucose oxidase biosensors to simultaneously measure in vivo the extracellular fluid glucose concentrations ([Gluc]ECF in the OB and the cortex. Under metabolic steady state, we have determined that the OB contained twice the amount of glucose found in the cortex. In both regions, the [Gluc]ECF was 2 fold higher in obese rats compared to their lean controls. Under induced dynamic glycemia conditions, insulin injection produced a greater decrease of [Gluc]ECF in the OB than in the cortex. Glucose injection did not affect OB [Gluc]ECF in Zucker fa/fa rats. In conclusion, these results emphasize the importance of glucose for the OB network function and provide strong arguments towards establishing the OB glucose-sensing as a key factor for sensory

Targeted delivery using peptide-functionalised gold nanoparticles to white adipose tissues of obese rats

Energy Technology Data Exchange (ETDEWEB)

Thovhogi, Ntevheleni; Sibuyi, Nicole [Medical Research Council, Diabetes Research Group (South Africa); Meyer, Mervin [University of the Western Cape, Biotechnology Department, DST/Mintek Nanotechnology Innovation Centre (South Africa); Onani, Martin [University of the Western Cape, Chemistry Department (South Africa); Madiehe, Abram, E-mail: amadiehe@csir.co.za [Medical Research Council, Diabetes Research Group (South Africa)

2015-02-15

Obesity is a complex metabolic disease of excessive fat accumulation. It is a worldwide epidemic affecting billions of people. Current pharmacological treatment of obesity remains limited and ineffective due to systemic drug toxicity and undesirable side effects. The current epidemic raises a serious need for development of safer drugs to treat obesity. Nanotechnology-based drug delivery system for administering pharmaceutical compound to achieve therapeutic effects is currently an exciting field in cancer treatment. Drug delivery involves either modification of drug release profile, absorption, distribution and/or elimination, for the benefit of improving drug efficacy and safety. Therefore, nanotechnology holds promise in the treatment of diseases including obesity. Gold nanoparticles (GNPs) functionalised with different biomolecules have been successfully used as drug delivery, labelling and imaging tools in biomedical research. In this study, the binding-specificity and targeting ability of adipose homing peptide (AHP)-functionalised GNPs (AHP-GNPs) were evaluated using flow cytometry and inductively coupled plasma-optical emission spectroscopy. Caco-2 cells and rats fed either chow or a high-fat diet were treated with either unfunctionalised GNPs or AHP-GNPs. Cellular uptake of GNPs was detected in cells treated with AHP-GNPs and not those treated with GNPs alone. Binding of AHP to cells was both temperature- and concentration-dependent. Compared to rats treated with GNPs alone, treatment of obese rats with AHP-GNPs resulted in the targeted delivery of the GNPs to the white adipose tissue (WAT). This paper reports the successful targeting of AHP-functionalised GNPs to WAT of obese rats.

Targeted delivery using peptide-functionalised gold nanoparticles to white adipose tissues of obese rats

International Nuclear Information System (INIS)

Thovhogi, Ntevheleni; Sibuyi, Nicole; Meyer, Mervin; Onani, Martin; Madiehe, Abram

2015-01-01

Obesity is a complex metabolic disease of excessive fat accumulation. It is a worldwide epidemic affecting billions of people. Current pharmacological treatment of obesity remains limited and ineffective due to systemic drug toxicity and undesirable side effects. The current epidemic raises a serious need for development of safer drugs to treat obesity. Nanotechnology-based drug delivery system for administering pharmaceutical compound to achieve therapeutic effects is currently an exciting field in cancer treatment. Drug delivery involves either modification of drug release profile, absorption, distribution and/or elimination, for the benefit of improving drug efficacy and safety. Therefore, nanotechnology holds promise in the treatment of diseases including obesity. Gold nanoparticles (GNPs) functionalised with different biomolecules have been successfully used as drug delivery, labelling and imaging tools in biomedical research. In this study, the binding-specificity and targeting ability of adipose homing peptide (AHP)-functionalised GNPs (AHP-GNPs) were evaluated using flow cytometry and inductively coupled plasma-optical emission spectroscopy. Caco-2 cells and rats fed either chow or a high-fat diet were treated with either unfunctionalised GNPs or AHP-GNPs. Cellular uptake of GNPs was detected in cells treated with AHP-GNPs and not those treated with GNPs alone. Binding of AHP to cells was both temperature- and concentration-dependent. Compared to rats treated with GNPs alone, treatment of obese rats with AHP-GNPs resulted in the targeted delivery of the GNPs to the white adipose tissue (WAT). This paper reports the successful targeting of AHP-functionalised GNPs to WAT of obese rats

Targeted delivery using peptide-functionalised gold nanoparticles to white adipose tissues of obese rats

Science.gov (United States)

Thovhogi, Ntevheleni; Sibuyi, Nicole; Meyer, Mervin; Onani, Martin; Madiehe, Abram

2015-02-01

Obesity is a complex metabolic disease of excessive fat accumulation. It is a worldwide epidemic affecting billions of people. Current pharmacological treatment of obesity remains limited and ineffective due to systemic drug toxicity and undesirable side effects. The current epidemic raises a serious need for development of safer drugs to treat obesity. Nanotechnology-based drug delivery system for administering pharmaceutical compound to achieve therapeutic effects is currently an exciting field in cancer treatment. Drug delivery involves either modification of drug release profile, absorption, distribution and/or elimination, for the benefit of improving drug efficacy and safety. Therefore, nanotechnology holds promise in the treatment of diseases including obesity. Gold nanoparticles (GNPs) functionalised with different biomolecules have been successfully used as drug delivery, labelling and imaging tools in biomedical research. In this study, the binding-specificity and targeting ability of adipose homing peptide (AHP)-functionalised GNPs (AHP-GNPs) were evaluated using flow cytometry and inductively coupled plasma-optical emission spectroscopy. Caco-2 cells and rats fed either chow or a high-fat diet were treated with either unfunctionalised GNPs or AHP-GNPs. Cellular uptake of GNPs was detected in cells treated with AHP-GNPs and not those treated with GNPs alone. Binding of AHP to cells was both temperature- and concentration-dependent. Compared to rats treated with GNPs alone, treatment of obese rats with AHP-GNPs resulted in the targeted delivery of the GNPs to the white adipose tissue (WAT). This paper reports the successful targeting of AHP-functionalised GNPs to WAT of obese rats.

Increased risk of cataract development in WNIN-obese rats due to accumulation of intralenticular sorbitol.

Science.gov (United States)

Reddy, Paduru Yadagiri; Giridharan, Nappan Veettil; Balakrishna, Nagalla; Validandi, Vakdevi; Pullakhandam, Raghu; Reddy, Geereddy Bhanuprakash

2013-05-01

Epidemiological studies have reported an association between obesity and increased incidence of ocular complications including cataract, yet the underlying biochemical and molecular mechanisms remained unclear. Previously we had demonstrated accumulation of sorbitol in the lens of obese rats (WNIN/Ob) and more so in a related strain with impaired glucose tolerance (WNIN/GR-Ob). However, only a few (15-20%) WNIN/Ob and WNIN/GR-Ob rats develop cataracts spontaneously with age. To gain further insights, we investigated the susceptibility of eye lens proteins of these obese rat strains to heat- and UV-induced aggregation in vitro, lens opacification upon glucose-mediated sorbitol accumulation ex vivo, and onset and progression of cataract was followed by galactose feeding and streptozotocin (STZ) injection. The results indicated increased susceptibility toward heat- or UV-induced aggregation of lens proteins in obese animals compared to their littermate lean controls. Further, in organ culture studies glucose-induced sorbitol accumulation was found to be higher and thus the lens opacification was faster in obese animals compared to their lean littermates. Also, the onset and progression of galactose- or STZ-induced cataractogenesis was faster in obese animals compared to lean control. These results together with our previous observations suggest that obesity status could lead to hyperaccumulation of sorbitol in eye lens, predisposing them to cataract, primarily by increasing their susceptibility to environmental and/or physiological factors. Further, intralenticular sorbitol accumulation beyond a threshold level could lead to cataract in WNIN/Ob and WNIN/GR-Ob rats. Copyright © 2013 International Union of Biochemistry and Molecular Biology, Inc.

Lipogenesis from U14C lactate in obese Zucker rat hepatocytes. Effect of albumin-bound oleate

International Nuclear Information System (INIS)

Porquet, D.; Serbource-Goguel, N.; Durand, G.; Maccario, J.; Feger, J.; Agneray, J.

1984-01-01

Lipogenesis from U( 14 C) lactate was studied in hepatocytes isolated from obese Zucker rats (fa/fa) their lean littermates (Fa/.) and Sprague Dawley rats. The distribution of radioactive carbon between the glycerol and the fatty acid moieties of the acylglycerols were studied. Radioactive lactate was better utilized for glycerol formation than it was for fatty acid formation in the obese rats. However, when oleate was added to the hepatocytic incubation medium, radioactive lactate was preferentially incorporated into the fatty acid moiety of the acyglycerols. Among the nutrients, lactate seems to be a better source of carbon than glucose for lipid synthesis. It has been shown that there is increased hepatic portal blood concentration of lactate several hours after eating: about 4 mM in Wistar rats and 10-15 mM in obese Zucher rats. We are interested in determin the incorporation of carbon from lactate either into glycerol or into fatty acid moieties of hepatic acylgylcerols, and in determining the influence of exogenous fatty acids on acylgylcerol synthesis, since a high level of circulating fatty acids in Zucher obese rats has been reported. The purpose was to determine the incorporaton of lactate into glycerol and fatty moieties of acylglycerols, under the influence of oleate

Diet composition alters the satiety effect of cholecystokinin in lean and obese Zucker rats.

Science.gov (United States)

Maggio, C A; Haraczkiewicz, E; Vasselli, J R

1988-01-01

Although exogenous administration of the peptide cholecystokinin (CCK) has been shown to reduce food intake in a variety of experimental situations, few studies have examined the influence of dietary content upon CCK's effectiveness, particularly in obese states. To evaluate the effectiveness of CCK administration in animals consuming high fat diets, groups of obese and lean Zucker rats were maintained on laboratory chow (CH), a high fat diet isocaloric to chow (IF), or a hypercaloric fat diet (HF). After a 17 hr fast, rats were given intraperitoneal injections of saline or ascending doses of 0.06 to 2.0 micrograms/kg of the synthetic octapeptide of CCK. On all diets, obese rats required higher doses of CCK to significantly reduce feeding and showed smaller intake reductions than lean rats (p less than 0.001). Despite higher baseline caloric intakes (p less than 0.001), rats of both genotypes maintained on HF displayed larger reductions of intake than those fed IF or CH (p less than 0.001). Intake reductions by either genotype maintained on IF or CH were not reliably different. The manner in which the satiety effect of CCK was enhanced in rats consuming the calorically dense, palatable HF diet is unclear but may be related to orosensory and/or postingestive attributes of the diet.

Sensory-specific satiety is intact in rats made obese on a high-fat high-sugar choice diet.

Science.gov (United States)

Myers, Kevin P

2017-05-01

Sensory-specific satiety (SSS) is the temporary decreased pleasantness of a recently eaten food, which inhibits further eating. Evidence is currently mixed whether SSS is weaker in obese people, and whether such difference precedes or follows from the obese state. Animal models allow testing whether diet-induced obesity causes SSS impairment. Female rats (n = 24) were randomly assigned to an obesogenic high-fat, high-sugar choice diet or chow-only control. Tests of SSS involved pre-feeding a single palatable, distinctively-flavored food (cheese- or cocoa-flavored) prior to free choice between both foods. Rats were tested for short-term SSS (2 h pre-feeding immediately followed by 2 h choice) and long-term SSS (3 day pre-feeding prior to choice on day 4). In both short- and long-term tests rats exhibited SSS by shifting preference towards the food not recently eaten. SSS was not impaired in obese rats. On the contrary, in the long-term tests they showed stronger SSS than controls. This demonstrates that neither the obese state nor a history of excess energy consumption fundamentally causes impaired SSS in rats. The putative impaired SSS in obese people may instead reflect a specific predisposition, properties of the obesogenic diet, or history of restrictive dieting and bingeing. Copyright © 2017 Elsevier Ltd. All rights reserved.

Modulatory effects of dietary supplementation by Vernonia amygdalina on high-fat-diet-induced obesity in Wistar rats.

Science.gov (United States)

Ekeleme-Egedigwe, Chima A; Ijeh, Ifeoma I; Okafor, Polycarp N

2017-01-01

Obesity is a growing public health problem arising from energy imbalance. The effect of 10% dietary incorporation of Vernonia amygdalina (VA) leaves into high-fat diets on some biological markers of adiposity and dyslipidaemia was investigated. Experimental diets consisted of the following – CD (control diet); HFD (high-fat diet); and HFD- VA (HFD containing 10% Vernonia amygdalina leaves) supplementation. Fifteen male Wistar rats were randomly divided into three groups of five animals each. After twelve weeks of feeding, serum lipid profile, blood glucose concentrations, body weight, adiposity index, feed intake, fecal loss and relative organ weight were investigated. Vernonia amygdalina (VA) inhibited HFD-induced weight gain and adiposity in rats. HFD-induced obese rats showed a significant increase in the levels of serum TG and TC compared to rats on a normal diet. However, the levels of serum TG, TC, LDL-C in HFDVA rats reduced significantly relative to the levels in HFD rats. Our results indicate that HFDVA reversed fatty infiltration leading to decreased body weight and fat tissue mass in the rats. These results suggested that incorporation of Vernonia amygdalina into high-fat diets may have therapeutic potentials for obesity and related metabolic disorders. Further studies to explore its possibility as an alternative pharmacologic agent to treat obesity are warranted.

Metabolic Syndrome and Bone: Pharmacologically Induced Diabetes has Deleterious Effect on Bone in Growing Obese Rats.

Science.gov (United States)

Bagi, Cedo M; Edwards, Kristin; Berryman, Edwin

2017-12-01

Metabolic syndrome and osteoporosis share similar risk factors. Also, patients with diabetes have a higher risk of osteoporosis and fracture. Liver manifestations, such as non-alcoholic steatohepatitis (NASH), of metabolic syndrome are further aggravated in diabetics and often lead to liver failure. Our objective was to create a rat model of human metabolic syndrome and determine the long-term impact of early-onset T1D on bone structure and strength in obese growing rats. Male rats were given either standard chow and RO water (Controls) or a high-fat, high-cholesterol diet and sugar water containing 55% fructose and 45% glucose (HFD). A third group of rats received the HFD diet and a single dose of streptozotocin to induce type 1 diabetes (HFD/Sz). Body weight and glucose tolerance tests were conducted several times during the course of the study. Serum chemistry, liver enzymes, and biomarkers of bone metabolism were evaluated at 10 and 28 weeks. Shear wave elastography and histology were used to assess liver fibrosis. Cancellous bone structure and cortical bone geometry were evaluated by mCT and strength by the 3-point bending method. Body mass and fat accumulation was significantly higher in HFD and HFD/Sz rats compared to Controls. Rats in both the HFD and HFD/Sz groups developed NASH, although the change was more severe in diabetic rats. Although both groups of obese rats had larger bones, their cancellous structure and cortical thickness were reduced, resulting in diminished strength that was further aggravated by diabetes. The HFD and HFD/Sz rats recapitulate MeSy in humans with liver pathology consistent with NASH. Our data provide strong indication that obesity accompanied by type 1 diabetes significantly aggravates comorbidities of MeSy, including the development of osteopenia and weaker bones. The juvenile rat skeleton seems to be more vulnerable to damage imposed by obesity and diabetes and may offer a model to inform the underlying pathology associated

Effects of intestinal bypass surgery on appetite, food intake, and body weight in obese and lean rats.

Science.gov (United States)

Sclafani, A; Koopmans, H S; Vasselli, J R; Reichman, M

1978-04-01

Jejunoileal bypass surgery or sham surgery was performed in female rats made obese with ventromedial hypothalamic (VMH) knife cuts, and in lean control rats. After bypass surgery, the VMH rats underate and lost weight until they reached the body weight of the control sham rats, and they then maintained their weight at control levels. Bypass surgery in lean rats produced much smaller reductions in food intake and body weight. Both bypass groups initially consumed less of a sucrose solution and milk diet during 1 h/day tests, but their intakes returned to near normal levels during the second postoperative month. Reconnection of the intestinal tract in the VMH-bypass rats led to renewed hyperphagia and return to obese body weights. A second experiment revealed that bypass surgery reduces food intake and body weight in genetically obese (fatty) rats, but this effect is not as pronounced as that displayed by VMH rats. These results confirm recent clinical observations that reduced appetite and caloric intake are the major causes of the weight loss produced by intestinal bypass surgery.

Cardiac remodeling and myocardial dysfunction in obese spontaneously hypertensive rats

Directory of Open Access Journals (Sweden)

Linz Dominik

2012-09-01

Full Text Available Abstract Background The additive effects of obesity and metabolic syndrome on left ventricular (LV maladaptive remodeling and function in hypertension are not characterized. Methods We compared an obese spontaneously hypertensive rat model (SHR-ob with lean spontaneously hypertensive rats (SHR-lean and normotensive controls (Ctr. LV-function was investigated by cardiac magnetic resonance imaging and invasive LV-pressure measurements. LV-interstitial fibrosis was quantified and protein levels of phospholamban (PLB, Serca2a and glucose transporters (GLUT1 and GLUT4 were determined by immunohistochemistry. Results Systolic blood pressure was similar in SHR-lean and SHR-ob (252 ± 7 vs. 242 ± 7 mmHg, p = 0.398 but was higher when compared to Ctr (155 ± 2 mmHg, p  Conclusion In addition to hypertension alone, metabolic syndrome and obesity adds to the myocardial phenotype by aggravating diastolic dysfunction and a progression towards systolic dysfunction. SHR-ob may be a useful model to develop new interventional and pharmacological treatment strategies for hypertensive heart disease and metabolic disorders.

Electronic Gaming and the Obesity Crisis

Science.gov (United States)

Calvert, Sandra L.; Staiano, Amanda E.; Bond, Bradley J.

2013-01-01

Children and adolescents in the United States and in many countries are projected to have shorter life spans than their parents, partly because of the obesity crisis engulfing the developed world. Exposure to electronic media is often implicated in this crisis because media use, including electronic game play, may promote sedentary behavior and…

Obesity and Subsequent Cardiovascular Events in Rats and The Potential Benefits of some Antioxidants Supplementation

International Nuclear Information System (INIS)

HEIBASHY, M.I.; El-Negmy, F.A.; Shahin, M.I.; Kelada, N.A.

2011-01-01

This study focuses on the relationship between the obesity and cardiovascular diseases (CVD) and the possible amelioration effects of curcumin or L-carnitine and their mixture on cardiac and lipid profiles tests. Obesity is associated with abnormal endothelial function and it is often inferred that the reduction in endothelial function is the result of a decrease in nitric oxide (NO). Moreover, asymmetric dimethyl arginine (ADMA) is an endogenous competitive inhibitor of nitric oxide synthase (NOs) activity. This modified amino acid is derived from proteins that have been post-translationally methylated and subsequently hydrolyzed. In the current study, obesity was induced in the rats by receiving orally 200 mg cholesterol/100 g by the aid of gastric tube together with injection i.m. 30 mg cholic acid/100 g for one month. After one month of induction of hyper-cholesterolemia in rats and in comparison to normal rats, the results showed that incorporation of extra cholesterol in diet led to a significant increase in serum cholesterol, triglycerides, LDL, HDL, VLDL-cholesterol and resistin levels. Moreover, significant elevations in the levels of AST, LDH, CK, ADMA and endotheline-1 were recorded in obese rats compared with normal rats. All previous parameters were corrected after the hypercholesterolemic rats were treated with curcumin or L-carnitine and their mixture depending on the time of treatment. These findings are consistent with the concept that curcumin and L-carnitine are hypolipidemic agents and powerful antioxidants

Dopamine D2 receptors in addiction-like reward dysfunction and compulsive eating in obese rats.

Science.gov (United States)

Johnson, Paul M; Kenny, Paul J

2010-05-01

We found that development of obesity was coupled with emergence of a progressively worsening deficit in neural reward responses. Similar changes in reward homeostasis induced by cocaine or heroin are considered to be crucial in triggering the transition from casual to compulsive drug-taking. Accordingly, we detected compulsive-like feeding behavior in obese but not lean rats, measured as palatable food consumption that was resistant to disruption by an aversive conditioned stimulus. Striatal dopamine D2 receptors (D2Rs) were downregulated in obese rats, as has been reported in humans addicted to drugs. Moreover, lentivirus-mediated knockdown of striatal D2Rs rapidly accelerated the development of addiction-like reward deficits and the onset of compulsive-like food seeking in rats with extended access to palatable high-fat food. These data demonstrate that overconsumption of palatable food triggers addiction-like neuroadaptive responses in brain reward circuits and drives the development of compulsive eating. Common hedonic mechanisms may therefore underlie obesity and drug addiction.

Exercise training starting at weaning age preserves cardiac pacemaker function in adulthood of diet-induced obese rats.

Science.gov (United States)

Carvalho de Lima, Daniel; Guimarães, Juliana Bohnen; Rodovalho, Gisele Vieira; Silveira, Simonton Andrade; Haibara, Andrea Siqueira; Coimbra, Cândido Celso

2014-08-01

Peripheral sympathetic overdrive in young obese subjects contributes to further aggravation of insulin resistance, diabetes, and hypertension, thus inducing worsening clinical conditions in adulthood. Exercise training has been considered a strategy to repair obesity autonomic dysfunction, thereby reducing the cardiometabolic risk. Therefore, the aim of this study was to assess the effect of early exercise training, starting immediately after weaning, on cardiac autonomic control in diet-induced obese rats. Male Wistar rats (weaning) were divided into four groups: (i) a control group (n = 6); (ii) an exercise-trained control group (n = 6); (iii) a diet-induced obesity group (n = 6); and (iv) an exercise-trained diet-induced obesity group (n = 6). The development of obesity was induced by 9 weeks of palatable diet intake, and the training program was implemented in a motor-driven treadmill (5 times per week) during the same period. After this period, animals were submitted to vein and artery catheter implantation to assess cardiac autonomic balance by methylatropine (3 mg/kg) and propranolol (4 mg/kg) administration. Exercise training increased running performance in both groups (p Exercise training also prevented the increased resting heart rate in obese rats, which seemed to be related to cardiac pacemaker activity preservation (p exercise program beginning at weaning age prevents cardiovascular dysfunction in obese rats, indicating that exercise training may be used as a nonpharmacological therapeutic strategy for the treatment of cardiometabolic diseases.

Anti-Obesity Effects of Onion Extract in Zucker Diabetic Fatty Rats

Directory of Open Access Journals (Sweden)

Kiharu Igarashi

2012-10-01

Full Text Available Anti-obesity effects of onion extract were determined in obesity and diabetes-prone Zucker diabetic fatty rats by measuring the efficacy of markers concerned with diabetes and obesity. Body and adipose tissue weights in 5% of onion extract-fed group were found to be significantly lower than the control group without onion extract. Fasting blood glucose and HOMA-IR levels were also improved, although the serum insulin and leptin levels did not show any remarkable difference. Serum triglyceride and free fatty acid levels in both the 3% and 5%-fed group were found to be reduced compared to the control group. Additionally the feeding of the onion extract increased the glucose tolerance. These results suggest that dietary onion extract is beneficial for improving diabetes by decreasing lipid levels. We also examined differentiation ability of rat white preadipocyte cells using the onion extract and its sulfur-containing components. Cycloalliin, S-methyl-l-cysteine, S-propyl-l-cysteine sulfoxide, dimethyl trisulfide, especially S-methyl-l-cysteine sulfoxide were reported to be effective in inhibiting formation of oil drop in the cells, suggesting that these compounds may be involved in the anti-obesity effect of the onion extract.

Effects of clenbuterol on insulin resistance in conscious obese Zucker rats.

Science.gov (United States)

Pan, S J; Hancock, J; Ding, Z; Fogt, D; Lee, M; Ivy, J L

2001-04-01

The present study was conducted to determine the effect of chronic administration of the long-acting beta(2)-adrenergic agonist clenbuterol on rats that are genetically prone to insulin resistance and impaired glucose tolerance. Obese Zucker rats (fa/fa) were given 1 mg/kg of clenbuterol by oral intubation daily for 5 wk. Controls received an equivalent volume of water according to the same schedule. At the end of the treatment, rats were catheterized for euglycemic-hyperinsulinemic (15 mU insulin. kg(-1). min(-1)) clamping. Clenbuterol did not change body weight compared with the control group but caused a redistribution of body weight: leg muscle weights increased, and abdominal fat weight decreased. The glucose infusion rate needed to maintain euglycemia and the rate of glucose disappearance were greater in the clenbuterol-treated rats. Furthermore, plasma insulin levels were decreased, and the rate of glucose uptake into hindlimb muscles and abdominal fat was increased in the clenbuterol-treated rats. This increased rate of glucose uptake was accompanied by a parallel increase in the rate of glycogen synthesis. The increase in muscle glucose uptake could not be ascribed to an increase in the glucose transport protein GLUT-4 in clenbuterol-treated rats. We conclude that chronic clenbuterol treatment reduces the insulin resistance of the obese Zucker rat by increasing insulin-stimulated muscle and adipose tissue glucose uptake. The improvements noted may be related to the repartitioning of body weight between tissues.

Anti-Diabetic Activity and Metabolic Changes Induced by Andrographis paniculata Plant Extract in Obese Diabetic Rats.

Science.gov (United States)

Akhtar, Muhammad Tayyab; Bin Mohd Sarib, Mohamad Syakir; Ismail, Intan Safinar; Abas, Faridah; Ismail, Amin; Lajis, Nordin Hj; Shaari, Khozirah

2016-08-09

Andrographis paniculata is an annual herb and widely cultivated in Southeast Asian countries for its medicinal use. In recent investigations, A. paniculata was found to be effective against Type 1 diabetes mellitus (Type 1 DM). Here, we used a non-genetic out-bred Sprague-Dawley rat model to test the antidiabetic activity of A. paniculata against Type 2 diabetes mellitus (Type 2 DM). Proton Nuclear Magnetic Resonance (¹H-NMR) spectroscopy in combination with multivariate data analyses was used to evaluate the A. paniculata and metformin induced metabolic effects on the obese and obese-diabetic (obdb) rat models. Compared to the normal rats, high levels of creatinine, lactate, and allantoin were found in the urine of obese rats, whereas, obese-diabetic rats were marked by high glucose, choline and taurine levels, and low lactate, formate, creatinine, citrate, 2-oxoglutarate, succinate, dimethylamine, acetoacetate, acetate, allantoin and hippurate levels. Treatment of A. paniculata leaf water extract was found to be quite effective in restoring the disturbed metabolic profile of obdb rats back towards normal conditions. Thisstudy shows the anti-diabetic potential of A. paniculata plant extract and strengthens the idea of using this plant against the diabetes. Further classical genetic methods and state of the art molecular techniques could provide insights into the molecular mechanisms involved in the pathogenesis of diabetes mellitus and anti-diabetic effects of A. paniculata water extract.

Preconception Prebiotic and Sitagliptin Treatment in Obese Rats Affects Pregnancy Outcomes and Offspring Microbiota, Adiposity, and Glycemia

Directory of Open Access Journals (Sweden)

Carol A. Dennison

2017-10-01

Full Text Available Maternal obesity is associated with increased risk of pregnancy complications and greater risk of obesity in offspring, but studies designed to examine preconception weight loss are limited. The objective of this study was to determine if a combined dietary [oligofructose (OFS] and pharmacological (sitagliptin preconception intervention could mitigate poor pregnancy outcomes associated with maternal obesity and improve offspring metabolic health and gut microbiota composition. Diet-induced obese female Sprague-Dawley rats were randomized to one of four intervention groups for 8 weeks: (1 Obese-Control (consumed control diet during intervention; (2 Obese-OFS (10% OFS diet; (3 Obese-S (sitagliptin drug; (4 Obese-OFS + S (combination treatment. Two reference groups were also included: (5 Obese-HFS (untreated obese consumed high fat/sucrose diet throughout study; (6 Lean-Control (lean reference group that were never obese and consumed control diet throughout. Offspring consumed control diet until 11 weeks of age followed by HFS diet until 17 weeks of age. The Obese-OFS + S rats lost weight during the intervention phase whereas the OFS and S treatments attenuated weight gain compared with Obese-HFS (p < 0.05. Gestational weight gain was lowest in Obese-OFS + S rats and highest in Obese-HFS rats (p < 0.05. Prepregnancy intervention did not affect reproductive parameters but did affect pregnancy outcomes including litter size. Male Obese-OFS offspring had significantly lower percent body fat than Obese-HFS at 17 weeks. Female Obese-S and Obese-OFS offspring had significantly lower fasting glucose at 17 weeks compared with Obese-Control and Obese-HFS. Clostridium cluster XI was higher in Obese-HFS and Obese-S dams at birth compared with all other groups. Dams with an adverse pregnancy outcome had significantly lower (p = 0.035 Lactobacillus spp. compared with dams with normal or small litters. At weaning, male offspring

Decreased expression of CD36 in circumvallate taste buds of high-fat diet induced obese rats.

Science.gov (United States)

Zhang, Xiao-Juan; Zhou, Li-Hong; Ban, Xiang; Liu, Dian-Xin; Jiang, Wei; Liu, Xiao-Min

2011-10-01

Mammals spontaneously prefer lipid rich foods. Overconsumption of high-fat diet leads to obesity and related diseases. Recent findings indicate that taste may participate in the orosensory perception of dietary lipids and the fatty taste may contribute to a preference for and excessive consumption of dietary fat. CD36, a trans-membrane glycoprotein, which is located in the taste buds of circumvallate papillae of rodents, appears to be a plausible receptor for this fatty taste. Obese subjects present a stronger preference for fatty foods, though the mechanisms involved are complex and are not fully investigated. Our data from immunofluorescence and real-time RT-PCR showed that the expression levels of CD36 in circumvallate taste buds were significantly lower in high-fat diet induced obese rats as compared with that of control rats fed a normal diet. These results suggest that decreased expression of CD36 in circumvallate taste buds of high-fat diet induced obese rats may be associated with diminished fatty taste sensitivity and in order to compensate the preference for dietary fat, rats consume more fatty foods. Therapeutic strategies designed to alter or manipulate CD36 expression or function in taste buds may have important implications in treating obesity and related diseases. Copyright © 2010 Elsevier GmbH. All rights reserved.

Altered susceptibility of an obese rat model to 13-week subchronic toxicity induced by 3-monochloropropane-1,2-diol.

Science.gov (United States)

Toyoda, Takeshi; Cho, Young-Man; Akagi, Jun-Ichi; Mizuta, Yasuko; Matsushita, Kohei; Nishikawa, Akiyoshi; Imaida, Katsumi; Ogawa, Kumiko

2017-01-01

3-Monochloropropane-1,2-diol (3-MCPD) is a heat-induced food contaminant that has been shown to be a nongenotoxic renal carcinogen. Although the toxicity of 3-MCPD has been widely investigated for decades, there is a further concern that 3-MCPD might exert more potent toxicity in high-risk population with underlying diseases such as hyperlipidemia associated with obesity. In the present study, we performed a 13-week subchronic toxicity study for 3-MCPD using an obesity rat model to investigate the differences in susceptibility between obese and normal individuals. Male F344 and obese Zucker (lean and fatty) rats were administered 0, 9, 28.5, 90, 285, or 900 ppm 3-MCPD in drinking water for 13 weeks. 3-MCPD treatment decreased body weight gain, increased relative kidney weights, induced anemia, and induced epithelial cell necrosis in epididymal ducts in all 3 strains. The degrees of epididymal damage were higher in F344 and lean rats than in fatty rats, while renal toxicity was most potent in F344 rats and comparable in lean and fatty rats. In contrast, the hematology data indicated that anemia was worse in fatty rats than in F344 and lean rats, and a significant decrease in hematopoietic cells in the bone marrow was observed only in fatty rats. The no-observed-adverse-effect level was estimated to be 28.5 ppm in all 3 strains for 3-MCPD. These results suggested that obese Zucker rats may be more susceptible to 3-MCPD-dependent toxicity in the hematopoietic tissues than their lean counterparts.

Pepsin Egg White Hydrolysate Ameliorates Obesity-Related Oxidative Stress, Inflammation and Steatosis in Zucker Fatty Rats.

Directory of Open Access Journals (Sweden)

M Garcés-Rimón

Full Text Available The aim of this work was to evaluate the effect of the administration of egg white hydrolysates on obesity-related disorders, with a focus on lipid metabolism, inflammation and oxidative stress, in Zucker fatty rats. Obese Zucker rats received water, pepsin egg white hydrolysate (750 mg/kg/day or Rhizopus aminopeptidase egg white hydrolysate (750 mg/kg/day for 12 weeks. Lean Zucker rats received water. Body weight, solid and liquid intakes were weekly measured. At the end of the study, urine, faeces, different organs and blood samples were collected. The consumption of egg white hydrolysed with pepsin significantly decreased the epididymal adipose tissue, improved hepatic steatosis, and lowered plasmatic concentration of free fatty acids in the obese animals. It also decreased plasma levels of tumor necrosis factor-alpha and reduced oxidative stress. Pepsin egg white hydrolysate could be used as a tool to improve obesity-related complications.

Increased Hypothalamic Inflammation Associated with the Susceptibility to Obesity in Rats Exposed to High-Fat Diet

Directory of Open Access Journals (Sweden)

Xiaoke Wang

2012-01-01

Full Text Available Inflammation has been implicated in the hypothalamic leptin and insulin resistance resulting defective food intake during high fat diet period. To investigate hypothalamic inflammation in dietary induced obesity (DIO and obesity resistant (DIO-R rats, we established rat models of DIO and DIO-R by feeding high fat diet for 10 weeks. Then we switched half of DIO and DIO-R rats to chow food and the other half to high fat diet for the following 8 weeks to explore hypothalamic inflammation response to the low fat diet intervention. Body weight, caloric intake, HOMA-IR, as well as the mRNA expression of hypothalamic TLR4, NF-κB, TNF-α, IL-1β, and IL-6 in DIO/HF rats were significantly increased compared to DIO-R/HF and CF rats, whereas IL-10 mRNA expression was lower in both DIO/HF and DIO-R/HF rats compared with CF rats. Switching to chow food from high fat diet reduced the body weight and improved insulin sensitivity but not affecting the expressions of studied inflammatory genes in DIO rats. Take together, upregulated hypothalamic inflammation may contribute to the overeating and development of obesity susceptibility induced by high fat diet. Switching to chow food had limited role in correcting hypothalamic inflammation in DIO rats during the intervention period.

Centrally administered urocortin 2 decreases gorging on high-fat diet in in both diet induced obesity-prone and -resistant rats

Science.gov (United States)

Cottone, Pietro; Sabino, Valentina; Nagy, Tim R.; Coscina, Donald V.; Levin, Barry E.; Zorrilla, Eric P.

2013-01-01

Objective Obesity is a costly, deadly public health problem for which new treatments are needed. Individual differences in meal pattern have been proposed to play a role in obesity risk. The present study tested the hypothesis that i) the microstructure of chronic high-fat diet intake differs between genetically selected Diet-Induced Obesity (DIO) and Diet Resistant (DR) rats, and ii) central administration of urocortin 2 (Ucn 2), a corticotropin-releasing factor type 2 (CRF2) agonist, decreases high-fat diet intake not only in lean DR rats, but also in obese DIO rats. Design Male, selectively bred DIO and DR rats (n=10/genotype) were chronically fed a high-fat diet. Food and water intake as well as ingestion microstructure were then compared under baseline conditions and following third intracerebroventricular injection of Ucn 2 (0, 0.1, 0.3, 1, 3 µg). Results Irrespective of genotype, Ucn 2 reduced nocturnal food intake with a minimum effective dose of 0.3 µg, suppressing high-fat diet intake by ~40% at the 3 µg dose. Ucn 2 also made rats of both genotypes eat smaller and briefer meals, including at doses that did not reduce drinking. Obese DIO rats ate fewer but larger meals than DR rats, which they ate more quickly and consumed with 2/3rd less water. Conclusions Unlike leptin and insulin, Ucn 2 retains its full central anorectic efficacy to reduce high-fat diet intake even in obese, genetically-prone DIO rats, which otherwise show a “gorging” meal pattern. These results open new opportunities of investigation towards treating some forms of diet-induced obesity. PMID:23478425

The Cooccurrence of Obesity, Osteoporosis, and Sarcopenia in the Ovariectomized Rat: A Study for Modeling Osteosarcopenic Obesity in Rodents

Directory of Open Access Journals (Sweden)

Zahra Ezzat-Zadeh

2017-01-01

Full Text Available Background. Obesity, osteoporosis, and sarcopenia may individually occur due to age-related gradual alterations in body composition. This study investigates the cooccurrence of these age-related diseases in female animals with low levels of ovarian hormone in the absence of complex multifactorial process of chronological aging. Methods. Thirty-six 5- and 10-month-old female rats were chosen to model pre- and postmenopausal women, respectively. Rats were divided into three treatment groups in each age category—sham, ovariectomized (ovx, and ovx + E2 (17β-estradiol, 10 μg/kg—and were pair-fed. Volunteer wheel running activity, body composition, bone microstructure, serum C-telopeptides of type I collagen, bone specific alkaline phosphatase, E2, and gastrocnemius and soleus muscles were analyzed. Results. The cooccurrence of osteoporosis, sarcopenia, and obesity was observed in the older ovx rats associated with a significant (p<0.05 increased fat mass (30%, bone loss (9.6%, decreased normalized muscle mass-to-body-weight ratio (10.5%, and a significant decrease in physical activity (57%. The ratio of tibial bone mineral density to combined muscle mass was significantly decreased in both ovx age categories. Conclusion. Ovariectomized rat could be used as an experimental model to examine the effect of loss of ovarian hormones, while controlling for energy intake and expenditure, to conduct obesity and body composition translational research in females without the confounding effect of genetic background.

Impact of metformin treatment and swimming exercise on visfatin levels in high-fat-induced obesity rats.

Science.gov (United States)

Gao, Ya; Wang, Changjiang; Pan, Tianrong; Luo, Li

2014-02-01

Visfatin is a recently discovered adipocytokine that contributes to glucose and obesity-related conditions. Until now, its responses to the insulin-sensitizing agent metformin and to exercise are largely unknown. We aim to investigate the impact of metformin treatment and/or swimming exercise on serum visfatin and visfatin levels in subcutaneous adipose tissue (SAT), peri-renal adipose tissue (PAT) and skeletal muscle (SM) of high-fat-induced obesity rats. Sprague-Dawley rats were fed a normal diet or a high-fat diet for 16 weeks to develop obesity model. The high-fat-induced obesity model rats were then randomized to metformin (MET), swimming exercise (SWI), or adjunctive therapy of metformin and swimming exercise (MAS), besides high-fat obesity control group and a normal control group, all with 10 rats per group. Zoometric and glycemic parameters, lipid profile, and serum visfatin levels were assessed at baseline and after 6 weeks of therapy. Visfatin levels in SAT, PAT and SM were determined by Western Blot. Metformin and swimming exercise improved lipid profile, and increased insulin sensitivity and body weight reduction were observed. Both metformin and swimming exercise down-regulated visfatin levels in SAT and PAT, while the adjunctive therapy conferred greater benefits, but no changes of visfatin levels were observed in SM. Our results indicate that visfatin down-regulation in SAT and PAT may be one of the mechanisms by which metformin and swimming exercise inhibit obesity.

Low fish oil intake improves insulin sensitivity, lipid profile and muscle metabolism on insulin resistant MSG-obese rats.

Science.gov (United States)

Yamazaki, Ricardo K; Brito, Gleisson A P; Coelho, Isabela; Pequitto, Danielle C T; Yamaguchi, Adriana A; Borghetti, Gina; Schiessel, Dalton Luiz; Kryczyk, Marcelo; Machado, Juliano; Rocha, Ricelli E R; Aikawa, Julia; Iagher, Fabiola; Naliwaiko, Katya; Tanhoffer, Ricardo A; Nunes, Everson A; Fernandes, Luiz Claudio

2011-04-28

Obesity is commonly associated with diabetes, cardiovascular diseases and cancer. The purpose of this study was to determinate the effect of a lower dose of fish oil supplementation on insulin sensitivity, lipid profile, and muscle metabolism in obese rats. Monosodium glutamate (MSG) (4 mg/g body weight) was injected in neonatal Wistar male rats. Three-month-old rats were divided in normal-weight control group (C), coconut fat-treated normal weight group (CO), fish oil-treated normal weight group (FO), obese control group (Ob), coconut fat-treated obese group (ObCO) and fish oil-treated obese group (ObFO). Obese insulin-resistant rats were supplemented with fish oil or coconut fat (1 g/kg/day) for 4 weeks. Insulin sensitivity, fasting blood biochemicals parameters, and skeletal muscle glucose metabolism were analyzed. Obese animals (Ob) presented higher Index Lee and 2.5 fold epididymal and retroperitoneal adipose tissue than C. Insulin sensitivity test (Kitt) showed that fish oil supplementation was able to maintain insulin sensitivity of obese rats (ObFO) similar to C. There were no changes in glucose and HDL-cholesterol levels amongst groups. Yet, ObFO revealed lower levels of total cholesterol (TC; 30%) and triacylglycerol (TG; 33%) compared to Ob. Finally, since exposed to insulin, ObFO skeletal muscle revealed an increase of 10% in lactate production, 38% in glycogen synthesis and 39% in oxidation of glucose compared to Ob. Low dose of fish oil supplementation (1 g/kg/day) was able to reduce TC and TG levels, in addition to improved systemic and muscle insulin sensitivity. These results lend credence to the benefits of n-3 fatty acids upon the deleterious effects of insulin resistance mechanisms.

Dietary supplementation with Agaricus blazei murill extract prevents diet-induced obesity and insulin resistance in rats.

Science.gov (United States)

Vincent, Mylène; Philippe, Erwann; Everard, Amandine; Kassis, Nadim; Rouch, Claude; Denom, Jessica; Takeda, Yorihiko; Uchiyama, Shoji; Delzenne, Nathalie M; Cani, Patrice D; Migrenne, Stéphanie; Magnan, Christophe

2013-03-01

Dietary supplement may potentially help to fight obesity and other metabolic disorders such as insulin-resistance and low-grade inflammation. The present study aimed to test whether supplementation with Agaricus blazei murill (ABM) extract could have an effect on diet-induced obesity in rats. Wistar rats were fed with control diet (CD) or high-fat diet (HF) and either with or without supplemented ABM for 20 weeks. HF diet-induced body weight gain and increased fat mass compared to CD. In addition HF-fed rats developed hyperleptinemia and insulinemia as well as insulin resistance and glucose intolerance. In HF-fed rats, visceral adipose tissue also expressed biomarkers of inflammation. ABM supplementation in HF rats had a protective effect against body weight gain and all study related disorders. This was not due to decreased food intake which remained significantly higher in HF rats whether supplemented with ABM or not compared to control. There was also no change in gut microbiota composition in HF supplemented with ABM. Interestingly, ABM supplementation induced an increase in both energy expenditure and locomotor activity which could partially explain its protective effect against diet-induced obesity. In addition a decrease in pancreatic lipase activity is also observed in jejunum of ABM-treated rats suggesting a decrease in lipid absorption. Taken together these data highlight a role for ABM to prevent body weight gain and related disorders in peripheral targets independently of effect in food intake in central nervous system. Copyright © 2012 The Obesity Society.

CARDIAC AND BEHAVIORAL-RESPONSES OF LONG-TERM OBESE AND LEAN ZUCKER RATS TO EMOTIONAL-STRESS

NARCIS (Netherlands)

NYAKAS, C; BALKAN, B; STEFFENS, AB; BOHUS, B

1995-01-01

Obesity is known as a risk factor in stress-related cardiovascular pathology in man. The length of obesity can be an important interacting variable. Therefore, cardiac and behavioral responses to emotional stress were studied in 1-year-old, genetically obese (fa/fa) and lean (Fa/-) male Zucker rats,

Anti-obesity effect of extract from fermented Curcuma longa L. through regulation of adipogenesis and lipolysis pathway in high-fat diet-induced obese rats

Science.gov (United States)

Kim, Ji Hye; Kim, Ok-Kyung; Yoon, Ho-Geun; Park, Jeongjin; You, Yanghee; Kim, Kyungmi; Lee, Yoo-Hyun; Choi, Kyung-Chul; Lee, Jeongmin; Jun, Woojin

2016-01-01

Background Even though Curcuma longa L. possesses various biological activities, it has strong flavor and taste, which decrease consumer palatability and limit industrial applications in food. Objective The present study investigates the effects of C. longa L. fermented with Aspergillus oryzae supplementation in 60% high-fat diet-induced obese rats measured by the activation of adipogenesis and lipolysis. Design Rats were divided into four groups (n=6 per group) after 1 week of acclimatization: a normal diet group comprised rats fed the AIN76A rodent diet; a high-fat diet-induced obese group with rats fed a 60% high-fat diet; a Garcinia cambogia treated group (positive control) with rats fed a 60% high-fat diet with G. cambogia 500 g/kg body weight (b.w.)/day; and an fermented C. longa L. 50% ethanolic extract treated group (FCE50) with rats fed a 60% high-fat diet with FCE50 500 g/kg b.w./day. Each group received the appropriate vehicle or sample daily by gastric intubation for 12 weeks. Results We found that FCE50 administration suppressed b.w. gain and reduced white adipose tissue weight, serum triglyceride (TG), and cholesterol in high-fat diet-induced obese rats. These results can be associated with the suppression of adipocyte differentiation and lipogenesis with a decrease in the mRNA expressions of fatty acid synthase, acetyl-CoA carboxylase, adipocyte protein 2, and lipoprotein lipase induced by FCE50 administration. In addition, FCE50 increased lipolysis and β-oxidation by up-regulating the expression of lipases such as adipose triglyceride lipase, hormone-sensitive lipase, adiponectin, and AMP-activated protein kinase. Conclusions These results suggest that FCE50 can be a candidate for the prevention of obesity via suppressing adipogenesis and promoting lipolysis. PMID:26822962

Obesity-induced sperm DNA methylation changes at satellite repeats are reprogrammed in rat offspring

Directory of Open Access Journals (Sweden)

Neil A Youngson

2016-01-01

Full Text Available There is now strong evidence that the paternal contribution to offspring phenotype at fertilisation is more than just DNA. However, the identity and mechanisms of this nongenetic inheritance are poorly understood. One of the more important questions in this research area is: do changes in sperm DNA methylation have phenotypic consequences for offspring? We have previously reported that offspring of obese male rats have altered glucose metabolism compared with controls and that this effect was inherited through nongenetic means. Here, we describe investigations into sperm DNA methylation in a new cohort using the same protocol. Male rats on a high-fat diet were 30% heavier than control-fed males at the time of mating (16-19 weeks old, n = 14/14. A small (0.25% increase in total 5-methyl-2Ͳ-deoxycytidine was detected in obese rat spermatozoa by liquid chromatography tandem mass spectrometry. Examination of the repetitive fraction of the genome with methyl-CpG binding domain protein-enriched genome sequencing (MBD-Seq and pyrosequencing revealed that retrotransposon DNA methylation states in spermatozoa were not affected by obesity, but methylation at satellite repeats throughout the genome was increased. However, examination of muscle, liver, and spermatozoa from male 27-week-old offspring from obese and control fathers (both groups from n = 8 fathers revealed that normal DNA methylation levels were restored during offspring development. Furthermore, no changes were found in three genomic imprints in obese rat spermatozoa. Our findings have implications for transgenerational epigenetic reprogramming. They suggest that postfertilization mechanisms exist for normalising some environmentally-induced DNA methylation changes in sperm cells.

Enhanced cocaine-induced locomotor sensitization and intrinsic excitability of NAc medium spiny neurons in adult but not adolescent rats susceptible to diet-induced obesity

Science.gov (United States)

Oginsky, Max F.; Maust, Joel D.; Corthell, John T.; Ferrario, Carrie R.

2015-01-01

Rationale Basal and diet-induced differences in mesolimbic function, particularly within the nucleus accumbens (NAc), may contribute to human obesity; these differences may be more pronounced in susceptible populations. Objectives We determined whether there are differences in cocaine-induced behavioral plasticity in rats that are susceptible vs. resistant to diet-induced obesity, and basal differences in the striatal neuron function in adult and adolescent obesity-prone and obesity-resistant rats. Methods Susceptible and resistant outbred rats were identified based on “junk-food” diet-induced obesity. Then, the induction and expression of cocaine-induced locomotor sensitization, which is mediated by enhanced striatal function and is associated with increased motivation for rewards and reward-paired cues, were evaluated. Basal differences in mesolimbic function were examined in selectively bred obesity-prone and obesity-resistant rats (P70-80 and P30-40) using both cocaine induced locomotion and whole-cell patch clamping approaches in NAc core medium spiny neurons (MSNs). Results In rats that became obese after eating “junk-food”, the expression of locomotor sensitization was enhanced compared to non-obese rats, with similarly strong responses to 7.5 and 15 mg/kg cocaine. Without diet manipulation, obesity-prone rats were hyper-responsive to the acute locomotor-activating effects of cocaine, and the intrinsic excitability of NAc core MSNs was enhanced by ~60% at positive and negative potentials. These differences were present in adult, but not adolescent rats. Post-synaptic glutamatergic transmission was similar between groups. Conclusions Mesolimbic systems, particularly NAc MSNs, are hyper-responsive in obesity-prone individuals; and interactions between predisposition and experience influence neurobehavioral plasticity in ways that may promote weight gain and hamper weight loss in susceptible rats. PMID:26612617

Tesaglitazar, a dual PPAR{alpha}/{gamma} agonist, ameliorates glucose and lipid intolerance in obese Zucker rats.

Science.gov (United States)

Oakes, Nicholas D; Thalén, Pia; Hultstrand, Therese; Jacinto, Severina; Camejo, Germán; Wallin, Boel; Ljung, Bengt

2005-10-01

Insulin resistance, impaired glucose tolerance, high circulating levels of free fatty acids (FFA), and postprandial hyperlipidemia are associated with the metabolic syndrome, which has been linked to increased risk of cardiovascular disease. We studied the metabolic responses to an oral glucose/triglyceride (TG) (1.7/2.0 g/kg lean body mass) load in three groups of conscious 7-h fasted Zucker rats: lean healthy controls, obese insulin-resistant/dyslipidemic controls, and obese rats treated with the dual peroxisome proliferator-activated receptor alpha/gamma agonist, tesaglitazar, 3 mumol.kg(-1).day(-1) for 4 wk. Untreated obese Zucker rats displayed marked insulin resistance, as well as glucose and lipid intolerance in response to the glucose/TG load. The 2-h postload area under the curve values were greater for glucose (+19%), insulin (+849%), FFA (+53%), and TG (+413%) compared with untreated lean controls. Treatment with tesaglitazar lowered fasting plasma glucose, improved glucose tolerance, substantially reduced fasting and postload insulin levels, and markedly lowered fasting TG and improved lipid tolerance. Fasting FFA were not affected, but postprandial FFA suppression was restored to levels seen in lean controls. Mechanisms of tesaglitazar-induced lowering of plasma TG were studied separately using the Triton WR1339 method. In anesthetized, 5-h fasted, obese Zucker rats, tesaglitazar reduced hepatic TG secretion by 47%, increased plasma TG clearance by 490%, and reduced very low-density lipoprotein (VLDL) apolipoprotein CIII content by 86%, compared with obese controls. In conclusion, the glucose/lipid tolerance test in obese Zucker rats appears to be a useful model of the metabolic syndrome that can be used to evaluate therapeutic effects on impaired postprandial glucose and lipid metabolism. The present work demonstrates that tesaglitazar ameliorates these abnormalities and enhances insulin sensitivity in this animal model.

Genomic and metabolic disposition of non-obese type 2 diabetic rats to increased myocardial fatty acid metabolism.

Directory of Open Access Journals (Sweden)

Sriram Devanathan

Full Text Available Lipotoxicity of the heart has been implicated as a leading cause of morbidity in Type 2 Diabetes Mellitus (T2DM. While numerous reports have demonstrated increased myocardial fatty acid (FA utilization in obese T2DM animal models, this diabetic phenotype has yet to be demonstrated in non-obese animal models of T2DM. Therefore, the present study investigates functional, metabolic, and genomic differences in myocardial FA metabolism in non-obese type 2 diabetic rats. The study utilized Goto-Kakizaki (GK rats at the age of 24 weeks. Each rat was imaged with small animal positron emission tomography (PET to estimate myocardial blood flow (MBF and myocardial FA metabolism. Echocardiograms (ECHOs were performed to assess cardiac function. Levels of triglycerides (TG and non-esterified fatty acids (NEFA were measured in both plasma and cardiac tissues. Finally, expression profiles for 168 genes that have been implicated in diabetes and FA metabolism were measured using quantitative PCR (qPCR arrays. GK rats exhibited increased NEFA and TG in both plasma and cardiac tissue. Quantitative PET imaging suggests that GK rats have increased FA metabolism. ECHO data indicates that GK rats have a significant increase in left ventricle mass index (LVMI and decrease in peak early diastolic mitral annular velocity (E' compared to Wistar rats, suggesting structural remodeling and impaired diastolic function. Of the 84 genes in each the diabetes and FA metabolism arrays, 17 genes in the diabetes array and 41 genes in the FA metabolism array were significantly up-regulated in GK rats. Our data suggest that GK rats' exhibit increased genomic disposition to FA and TG metabolism independent of obesity.

Low fish oil intake improves insulin sensitivity, lipid profile and muscle metabolism on insulin resistant MSG-obese rats

Directory of Open Access Journals (Sweden)

Iagher Fabiola

2011-04-01

Full Text Available Abstract Background Obesity is commonly associated with diabetes, cardiovascular diseases and cancer. The purpose of this study was to determinate the effect of a lower dose of fish oil supplementation on insulin sensitivity, lipid profile, and muscle metabolism in obese rats. Methods Monosodium glutamate (MSG (4 mg/g body weight was injected in neonatal Wistar male rats. Three-month-old rats were divided in normal-weight control group (C, coconut fat-treated normal weight group (CO, fish oil-treated normal weight group (FO, obese control group (Ob, coconut fat-treated obese group (ObCO and fish oil-treated obese group (ObFO. Obese insulin-resistant rats were supplemented with fish oil or coconut fat (1 g/kg/day for 4 weeks. Insulin sensitivity, fasting blood biochemicals parameters, and skeletal muscle glucose metabolism were analyzed. Results Obese animals (Ob presented higher Index Lee and 2.5 fold epididymal and retroperitoneal adipose tissue than C. Insulin sensitivity test (Kitt showed that fish oil supplementation was able to maintain insulin sensitivity of obese rats (ObFO similar to C. There were no changes in glucose and HDL-cholesterol levels amongst groups. Yet, ObFO revealed lower levels of total cholesterol (TC; 30% and triacylglycerol (TG; 33% compared to Ob. Finally, since exposed to insulin, ObFO skeletal muscle revealed an increase of 10% in lactate production, 38% in glycogen synthesis and 39% in oxidation of glucose compared to Ob. Conclusions Low dose of fish oil supplementation (1 g/kg/day was able to reduce TC and TG levels, in addition to improved systemic and muscle insulin sensitivity. These results lend credence to the benefits of n-3 fatty acids upon the deleterious effects of insulin resistance mechanisms.

Implications of obesity for tendon structure, ultrastructure and biochemistry: a study on Zucker rats.

Science.gov (United States)

Biancalana, Adriano; Velloso, Lício Augusto; Taboga, Sebastião Roberto; Gomes, Laurecir

2012-02-01

The extracellular matrix consists of collagen, proteoglycans and non-collagen proteins. The incidence of obesity and associated diseases is currently increasing in developed countries. Obesity is considered to be a disease of modern times, and genes predisposing to the disease have been identified in humans and animals. The objective of the present study was to compare the morphological and biochemical aspects of the deep digital flexor tendon of lean (Fa/Fa or Fa/fa) and genetically obese (fa/fa) Zucker rats. Ultrastructural analysis showed the presence of lipid droplets in both groups, whereas disorganized collagen fibril bundles were observed in obese animals. Lean animals presented a larger amount of non-collagen proteins and glycosaminoglycans than obese rats. We propose that the overweight and lesser physical activity in obese animals may have provoked the alterations in the composition and organization of extracellular matrix components but a genetic mechanism cannot be excluded. These alterations might be related to organizational and structural modifications in the collagen bundles that influence the mechanical properties of tendons and the progression to a pathological state. Copyright © 2011 Elsevier Ltd. All rights reserved.

Protective Role of Co-administration of Vitamin D in Monosodium Glutamate Induced Obesity in Female Rats.

Science.gov (United States)

Nandan, Padmanabha; Nayanatara, Arun Kumar; Poojary, Roopesh; Bhagyalakshmi, K; Nirupama, M; Kini, Rekha D

2018-02-01

Obesity in females is an emerging health problem. The consumption of MSG has been considered as a risk factor for obesity. The tastemakers in Chinese and fast foods, such as fish sauce and soy sauce, contain very high levels of glutamate. The deficiency of Vitamin D is associated with obesity and metabolic syndrome. Therefore, the present study aimed to determine the effect of co-administration of Vitamin D on body weight control in MSG-induced obese rats. Eighteen adult female Wistar rats were randomly divided into three groups equally. The first group (Group I) was treated with saline served as the control; the second group (Group II) received a daily oral dose of 5 g/kg Body weight of MSG; the third group (Group III) received the same dose of MSG along with calcitriol (0.2 mcg/kg BW) for 15 days. The body weight, food, and water intake were measured. MSG treated rats showed a significant increase (P body weight, food, and water intake but significant decrease (P body weight gain in MSG-induced obese rats. Active agents in Vitamin D are useful for the prevention and treatment of obesity. Foods tested with high glutamate levels can be fortified with minute quantities of calcitriol to combat the adverse effects without compromising on the taste of the food processed. The fortification of junk foods might also combat largely prevalent Vitamin D deficiency in India. Copyright © 2018 National Medical Association. Published by Elsevier Inc. All rights reserved.

Tesofensine induces appetite suppression and weight loss with reversal of low forebrain dopamine levels in the diet-induced obese rat

DEFF Research Database (Denmark)

Hansen, Henrik H; Jensen, Majbrit M; Overgaard, Agnete

2013-01-01

is not clarified. Tesofensine effectively induces appetite suppression in the diet-induced obese (DIO) rat partially being ascribed to an indirect stimulation of central dopamine receptor function subsequent to blocked dopamine transporter activity. This is interesting, as obese patients have reduced central......Tesofensine is a triple monoamine reuptake inhibitor which inhibits noradrenaline, 5-HT and dopamine reuptake. Tesofensine is currently in clinical development for the treatment of obesity, however, the pharmacological basis for its strong and sustained effects in obesity management...... as compared to age-matched chow-fed rats. DIO rats also exhibited a marked reduction in baseline extracellular dopamine levels in the nucleus accumbens (NAcc) and prefrontal cortex (PFC), as compared to chow-fed rats using microdialysis. While acute administration of tesofensine (2.0mg/kg) normalized accumbal...

Accumulation of ceramide in slow-twitch muscle contributes to the development of insulin resistance in the obese JCR:LA-cp rat.

Science.gov (United States)

Fillmore, Natasha; Keung, Wendy; Kelly, Sandra E; Proctor, Spencer D; Lopaschuk, Gary D; Ussher, John R

2015-06-01

What is the central question of this study? The aim was to determine whether the accumulation of ceramide contributes to skeletal muscle insulin resistance in the JCR obese rat. What is the main finding and its importance? Our main new finding is that ceramides accumulate only in slow-twitch skeletal muscle in the JCR obese rat and that reducing ceramide content in this muscle type by inhibition of serine palmitoyl transferase-1 halts the progression of insulin resistance in this rat model predisposed to early development of type 2 diabetes. Our findings highlight the importance of assessing insulin signalling/sensitivity and lipid intermediate accumulation in different muscle fibre types. It has been postulated that insulin resistance results from the accumulation of cytosolic lipid metabolites (i.e. diacylglycerol/ceramide) that impede insulin signalling and impair glucose homeostasis. De novo ceramide synthesis is catalysed by serine palmitoyl transferase-1. Our aim was to determine whether de novo ceramide synthesis plays a role during development of insulin resistance in the JCR:LA-cp obese rat. Ten-week-old JCR:LA-cp obese rats were supplemented with either vehicle or the serine palmitoyl transferase-1 inhibitor l-cycloserine (360 mg l(-1) ) in their drinking water for a 2 week period, and glycaemia was assessed by meal tolerance testing. Treatment of JCR:LA-cp obese rats with l-cycloserine improved their plasma glucose and insulin levels during a meal tolerance test. Examination of muscle lipid metabolites and protein phosphorylation patterns revealed differential signatures in slow-twitch (soleus) versus fast-twitch muscle (gastrocnemius), in that ceramide levels were increased in soleus but not gastrocnemius muscles of JCR:LA-cp obese rats. Likewise, improved glycaemia in l-cycloserine-treated JCR:LA-cp obese rats was associated with enhanced Akt and pyruvate dehydrogenase signalling in soleus but not gastrocnemius muscles, probably as a result of l

An Optimized IES Method and Its Inhibitory Effects and Mechanisms on Food Intake and Body Weight in Diet-Induced Obese Rats: IES for Obesity.

Science.gov (United States)

Wan, Xinyue; Yin, Jieyun; Foreman, Robert; Chen, Jiande D Z

2017-12-01

This paper aims to optimize stimulation parameters and durations for intestinal electrical stimulation (IES) and to explore the effects and mechanisms of chronic IES with optimized methodology in obesity rats. Sixteen diet-induced obese (DIO) rats were tested for food intake with four different sets of IES parameters each lasting 1 week. Then, another 12 DIO rats were used to test the effect of IES on food intake with different stimulation durations. Finally, 16 DIO rats were treated with IES or sham-IES for 4 weeks. Meal patterns, food intake, and body weight were observed. Mechanisms involving gastrointestinal motility, ghrelin, and glucagon-like peptide-1 (GLP-1) were studied. (1) Acute IES with different parameters showed different inhibitory effects on food intake, and the most effective parameters were 0.6 s on, 0.9 s off, 80 Hz, 2 ms, and 4 mA with which 26.3% decrease in food intake was noted (p fasting and postprandial plasma levels of GLP-1 but not ghrelin. Twelve-hour daily IES using optimized stimulation parameters reduces food intake and body weight in DIO rats by altering gastrointestinal motility and GLP-1. The IES methodology derived in this study may have a therapeutic potential for obesity.

Oral salmon calcitonin protects against impaired fasting glycemia, glucose intolerance, and obesity induced by high-fat diet and ovariectomy in rats.

Science.gov (United States)

Feigh, Michael; Andreassen, Kim V; Hjuler, Sara T; Nielsen, Rasmus H; Christiansen, Claus; Henriksen, Kim; Karsdal, Morten A

2013-07-01

Oral salmon calcitonin (sCT) has demonstrated clinical efficacy in treating osteoporosis in postmenopausal women. The postmenopausal state is also associated with obesity-related insulin resistance (IR) and type 2 diabetes. The aim of this study was to investigate the preventive effects of oral sCT on energy and glucose homeostasis in high-fat diet (HFD)- and ovariectomy (OVX)-induced obese rats. Furthermore, the weight-regulatory and gluco-regulatory effects of short-term oral sCT intervention on HFD-induced obese rats were explored. For prevention, female rats exposed to HFD with or without OVX were treated with oral sCT for 5 weeks. As intervention, HFD-induced obese male rats were treated with oral sCT for 4 days. Body weight, food intake, and plasma glucose, insulin, and leptin levels were measured, and the clinical homeostasis model assessment for insulin resistance (HOMA-IR) index was calculated. In addition, oral glucose tolerance was evaluated in the systemic and portal circulations. For prevention, oral sCT reduced body weight by ∼16% to 19% (P fasting glycemia (P obesity. Furthermore, oral sCT significantly reduced the incremental area under the curve for plasma glucose and insulin by ∼40% and ∼70%, respectively, during glucose tolerance testing. As intervention in HFD-induced obese rats, oral sCT reduced body weight, fasting glycemia, and insulinemia in conjunction with HOMA-IR (P obese rats, indicating the clinical usefulness of oral sCT in postmenopausal obesity-related IR and type 2 diabetes.

Dipeptidyl Peptidase-4 Inhibitor, Vildagliptin, Improves Trabecular Bone Mineral Density and Microstructure in Obese, Insulin-Resistant, Pre-diabetic Rats.

Science.gov (United States)

Charoenphandhu, Narattaphol; Suntornsaratoon, Panan; Sa-Nguanmoo, Piangkwan; Tanajak, Pongpan; Teerapornpuntakit, Jarinthorn; Aeimlapa, Ratchaneevan; Chattipakorn, Nipon; Chattipakorn, Siriporn

2018-02-02

Obese insulin resistance and type 2 diabetes mellitus profoundly impair bone mechanical properties and bone quality. However, because several antidiabetes drugs, especially thiazolidinediones, further aggravate bone loss in individuals with diabetes, diabetic osteopathy should not be treated by using simply any glucose-lowering agents. Recently, incretins have been reported to affect osteoblast function positively. The present study aimed to investigate the effects of vildagliptin, an inhibitor of dipeptidyl peptidase-4, on bone of rats with high-fat-diet-induced prediabetes. Male rats were fed a high-fat diet for 12 weeks to induce obese insulin resistance and then treated with vildagliptin for 4 weeks. The effects of the drug on bone were determined by microcomputed tomography and bone histomorphometry. Vildagliptin markedly improved insulin resistance in these obese insulin-resistant rats. It also significantly increased volumetric bone mineral density. Specifically, vildagliptin-treated obese insulin-resistant rats exhibited higher trabecular volumetric bone mineral density than vehicle-treated obese insulin-resistant rats, whereas cortical volumetric bone mineral density, cortical thickness and area were not changed. Bone histomorphometric analysis in a trabecular-rich area (i.e. tibial metaphysis) revealed greater trabecular bone volume and number and less trabecular separation without change in trabecular thickness, osteocyte lacunar area or cortical thickness in the vildagliptin-treated group. Vildagliptin had a beneficial effect on the bone of obese insulin-resistant rats with prediabetes, particularly at the trabecular site. Such benefit probably results from enhanced bone formation rather than from suppressed bone resorption. Copyright © 2018 Diabetes Canada. Published by Elsevier Inc. All rights reserved.

Liuwei Dihuang Lowers Body Weight and Improves Insulin and Leptin Sensitivity in Obese Rats

Directory of Open Access Journals (Sweden)

Benjamin Perry

2012-01-01

Full Text Available The present study was aimed at investigating the efficacy and mechanism(s of action of a Chinese herbal formulation, Liuwei Dihuang (LWDH, as a prospective natural weight-lowering product. Following a 2-week acclimation period, 48 obesity-prone (OP-CD rats were divided into 4 groups (n=12 each. One group served as a positive control for obesity (OP, while the other 3 were challenged twice daily by oral gavage with total daily dosages of 500, 1500, or 3500 mg/kg BW LWDH, respectively, for 10 weeks. One group (n=12 of obesity-resistant (OR-CD rats served as the normal control group. All rats were fed the same AIN-93G diet modified to contain 60% energy from fat. The highest LWDH dose significantly reduced body weight during the last 4 weeks of treatment. Food intake was reduced beginning in week 2. The high LWDH dose lowered serum triglyceride (TG and nonesterified fatty acid (NEFA levels and body fat. Both the high and medium doses also lowered serum leptin and insulin levels. Liver function testing revealed no adverse side effects under the current experimental conditions. The results of the present study suggest that LWDH has potential as a preventive or therapeutic natural product against overweight and obesity.

Caloric Restriction in Lean and Obese Strains of Laboratory Rat: Effects on Body Composition, Metabolism, Growth, and Overall Health

Science.gov (United States)

NEW FINDINGS: What is the central question of this study? How do lean and obese rats respond physiologically to caloric restriction? What is the main finding and its importance? Obese rats show marked benefits compared with lean animals. Reduced body fat is associated with improv...

Arcuate nucleus of hypothalamus is involved in mediating the satiety effect of electroacupuncture in obese rats.

Science.gov (United States)

Fei Wang; Tian, De Run; Tso, Patrick; Han, Ji Sheng

2011-12-01

Obesity is a major health problem in the world. Since effective remedies are rare, researchers are trying to discover new therapies for obesity, and acupuncture is among the most popular alternative approaches. This study investigated the anti-obesity mechanisms of EA, using a rat model of diet-induced obesity. After feeding with a high-fat diet for 9 weeks, a number of rats who gained weight that surpassed the maximal body weight of rats in the chow-fed group were considered obese and employed in the study. A 2 Hz EA treatment at the acupoints ST36/SP6 with the intensity increasing stepwise from 0.5-1-1.5 mA was given once a day for 30 min. Rats treated with EA showed significantly decreased food intake and reduced body weight compared with the rats in DIO and restraint group. EA treatment increased peptide levels of α-MSH and mRNA levels of its precursor POMC in the arcuate nuclear of hypothalamus (ARH) neurons. In addition, the cerebral spinal fluid (CSF) content of α-MSH was elevated by EA application. ARH lesions by monosodium glutamate abolished the inhibition effect of EA on food intake and body weight. A non-acupoint stimulation did not show the benefit effect on food intake inhibition and body weight reduction compared with restraint and ST36/SP6 EA treatment. We concluded that EA treatment at ST36/SP6 acted through ARH to significantly inhibit food intake and body weight gain when fed a high-fat diet and that the stimulation of α-MSH expression and release might be involved in the mechanism. Copyright © 2011 Elsevier Inc. All rights reserved.

Cardiac, Metabolic and Molecular Profiles of Sedentary Rats in the Initial Moment of Obesity

Directory of Open Access Journals (Sweden)

Bruno Barcellos Jacobsen

2017-10-01

Full Text Available Abstract Background: Different types of high-fat and/or high-energy diets have been used to induce obesity in rodents. However, few studies have reported on the effects observed at the initial stage of obesity induced by high-fat feeding on cardiac functional and structural remodelling. Objective: To characterize the initial moment of obesity and investigate both metabolic and cardiac parameters. In addition, the role of Ca2+ handling in short-term exposure to obesity was verified. Methods: Thirty-day-old male Wistar rats were randomized into two groups (n = 19 each: control (C; standard diet and high-fat diet (HF, unsaturated high-fat diet. The initial moment of obesity was defined by weekly measurement of body weight (BW complemented by adiposity index (AI. Cardiac remodelling was assessed by morphological, histological, echocardiographic and papillary muscle analysis. Ca2+ handling proteins were determined by Western Blot. Results: The initial moment of obesity occurred at the 3rd week. Compared with C rats, the HF rats had higher final BW (4%, body fat (20%, AI (14.5%, insulin levels (39.7%, leptin (62.4% and low-density lipoprotein cholesterol (15.5% but did not exhibit alterations in systolic blood pressure. Echocardiographic evaluation did not show alterations in cardiac parameters. In the HF group, muscles were observed to increase their +dT/dt (C: 52.6 ± 9.0 g/mm2/s and HF: 68.0 ± 17.0 g/mm2/s; p < 0.05. In addition, there was no changes in the cardiac expression of Ca2+ handling proteins. Conclusion: The initial moment of obesity promotes alterations to hormonal and lipid profiles without cardiac damage or changes in Ca2+ handling.

Low fish oil intake improves insulin sensitivity, lipid profile and muscle metabolism on insulin resistant MSG-obese rats

OpenAIRE

Iagher Fabiola; Aikawa Julia; Rocha Ricelli ER; Machado Juliano; Kryczyk Marcelo; Schiessel Dalton; Borghetti Gina; Yamaguchi Adriana A; Pequitto Danielle CT; Coelho Isabela; Brito Gleisson AP; Yamazaki Ricardo K; Naliwaiko Katya; Tanhoffer Ricardo A; Nunes Everson A

2011-01-01

Abstract Background Obesity is commonly associated with diabetes, cardiovascular diseases and cancer. The purpose of this study was to determinate the effect of a lower dose of fish oil supplementation on insulin sensitivity, lipid profile, and muscle metabolism in obese rats. Methods Monosodium glutamate (MSG) (4 mg/g body weight) was injected in neonatal Wistar male rats. Three-month-old rats were divided in normal-weight control group (C), coconut fat-treated normal weight group (CO), fish...

Individual Differences in Cue-Induced Motivation and Striatal Systems in Rats Susceptible to Diet-Induced Obesity.

Science.gov (United States)

Robinson, Mike J F; Burghardt, Paul R; Patterson, Christa M; Nobile, Cameron W; Akil, Huda; Watson, Stanley J; Berridge, Kent C; Ferrario, Carrie R

2015-08-01

Pavlovian cues associated with junk-foods (caloric, highly sweet, and/or fatty foods), like the smell of brownies, can elicit craving to eat and increase the amount of food consumed. People who are more susceptible to these motivational effects of food cues may have a higher risk for becoming obese. Further, overconsumption of junk-foods leading to the development of obesity may itself heighten attraction to food cues. Here, we used a model of individual susceptibility to junk-foods diet-induced obesity to determine whether there are pre-existing and/or diet-induced increases in attraction to and motivation for sucrose-paired cues (ie, incentive salience or 'wanting'). We also assessed diet- vs obesity-associated alterations in mesolimbic function and receptor expression. We found that rats susceptible to diet-induced obesity displayed heightened conditioned approach prior to the development of obesity. In addition, after junk-food diet exposure, those rats that developed obesity also showed increased willingness to gain access to a sucrose cue. Heightened 'wanting' was not due to individual differences in the hedonic impact ('liking') of sucrose. Neurobiologically, Mu opioid receptor mRNA expression was lower in striatal 'hot-spots' that generate eating or hedonic impact only in those rats that became obese. In contrast, prolonged exposure to junk-food resulted in cross-sensitization to amphetamine-induced locomotion and downregulation of striatal D2R mRNA regardless of the development of obesity. Together these data shed light on individual differences in behavioral and neurobiological consequences of exposure to junk-food diets and the potential contribution of incentive sensitization in susceptible individuals to greater food cue-triggered motivation.

Individual Differences in Cue-Induced Motivation and Striatal Systems in Rats Susceptible to Diet-Induced Obesity

Science.gov (United States)

Robinson, Mike JF; Burghardt, Paul R; Patterson, Christa M; Nobile, Cameron W; Akil, Huda; Watson, Stanley J; Berridge, Kent C; Ferrario, Carrie R

2015-01-01

Pavlovian cues associated with junk-foods (caloric, highly sweet, and/or fatty foods), like the smell of brownies, can elicit craving to eat and increase the amount of food consumed. People who are more susceptible to these motivational effects of food cues may have a higher risk for becoming obese. Further, overconsumption of junk-foods leading to the development of obesity may itself heighten attraction to food cues. Here, we used a model of individual susceptibility to junk-foods diet-induced obesity to determine whether there are pre-existing and/or diet-induced increases in attraction to and motivation for sucrose-paired cues (ie, incentive salience or ‘wanting’). We also assessed diet- vs obesity-associated alterations in mesolimbic function and receptor expression. We found that rats susceptible to diet-induced obesity displayed heightened conditioned approach prior to the development of obesity. In addition, after junk-food diet exposure, those rats that developed obesity also showed increased willingness to gain access to a sucrose cue. Heightened ‘wanting’ was not due to individual differences in the hedonic impact (‘liking’) of sucrose. Neurobiologically, Mu opioid receptor mRNA expression was lower in striatal ‘hot-spots’ that generate eating or hedonic impact only in those rats that became obese. In contrast, prolonged exposure to junk-food resulted in cross-sensitization to amphetamine-induced locomotion and downregulation of striatal D2R mRNA regardless of the development of obesity. Together these data shed light on individual differences in behavioral and neurobiological consequences of exposure to junk-food diets and the potential contribution of incentive sensitization in susceptible individuals to greater food cue-triggered motivation. PMID:25761571

Supplementation of Syzygium cumini seed powder prevented obesity, glucose intolerance, hyperlipidemia and oxidative stress in high carbohydrate high fat diet induced obese rats.

Science.gov (United States)

Ulla, Anayt; Alam, Md Ashraful; Sikder, Biswajit; Sumi, Farzana Akter; Rahman, Md Mizanur; Habib, Zaki Farhad; Mohammed, Mostafe Khalid; Subhan, Nusrat; Hossain, Hemayet; Reza, Hasan Mahmud

2017-06-02

Obesity and related complications have now became epidemic both in developed and developing countries. Cafeteria type diet mainly composed of high fat high carbohydrate components which plays a significant role in the development of obesity and metabolic syndrome. This study investigated the effect of Syzygium cumini seed powder on fat accumulation and dyslipidemia in high carbohydrate high fat diet (HCHF) induced obese rats. Male Wistar rats were fed with HCHF diet ad libitum, and the rats on HCHF diet were supplemented with Syzygium cumini seed powder for 56 days (2.5% w/w of diet). Oral glucose tolerance test, lipid parameters, liver marker enzymes (AST, ALT and ALP) and lipid peroxidation products were analyzed at the end of 56 days. Moreover, antioxidant enzyme activities were also measured in all groups of rats. Supplementation with Syzygium cumini seed powder significantly reduced body weight gain, white adipose tissue (WAT) weights, blood glucose, serum insulin, and plasma lipids such as total cholesterol, triglyceride, LDL and HDL concentration. Syzygium cumini seed powder supplementation in HCHF rats improved serum aspartate amino transferase (AST), alanine amino transferase (ALT), and alkaline phosphatase (ALP) activities. Syzygium cumini seed powder supplementation also reduced the hepatic thiobarbituric acid reactive substances (TBARS) and elevated the antioxidant enzyme superoxide dismutase (SOD) and catalase (CAT) activities as well as increased glutathione (GSH) concentration. In addition, histological assessment showed that Syzygium cumini seed powder supplementation prevented inflammatory cell infiltration; fatty droplet deposition and fibrosis in liver of HCHFD fed rats. Our investigation suggests that Syzygium cumini seed powder supplementation prevents oxidative stress and showed anti-inflammatory and antifibrotic activity in liver of HCHF diet fed rats. In addition, Syzygium cumini seed powder may be beneficial in ameliorating insulin

[Electronic media in obesity prevention in childhood and adolescence].

Science.gov (United States)

Weihrauch-Blüher, Susann; Koormann, Stefanie; Brauchmann, Jana; Wiegand, Susanna

2016-11-01

The increasing prevalence of childhood obesity is - amongst other factors - due to changed leisure time habits with decreased physical activity and increased media consumption. However, electronic media such as tablets and smartphones might also provide a novel intervention approach to prevent obesity in childhood and adolescence. A summary of interventions applying electronic media to prevent childhood obesity is provided to investigate short term effects as well as long term results of these interventions. A systematic literature search was performed in PubMed/Web of Science to identify randomized and/or controlled studies that have investigated the efficacy of electronic media for obesity prevention below the age of 18. A total of 909 studies were identified, and 88 studies were included in the analysis. Active video games did increase physical activity compared to inactive games when applied within a peer group. Interventions via telephone had positive effects on certain lifestyle-relevant behaviours. Interventions via mobile were shown to decrease dropout rates by sending regular SMS messages. To date, interventions via smartphones are scarce for adolescents; however, they might improve cardiorespiratory fitness. The results from internet-based interventions showed a trend towards positive effects on lifestyle-relevant behaviors. The combination of different electronic media did not show superior results compared to interventions with only one medium. Interventions via TV, DVD or video-based interventions may increase physical activity when offered as an incentive, however, effects on weight status were not observed. Children and adolescents currently grow up in a technology- and media-rich society with computers, tablets, smartphones, etc. used daily. Thus, interventions applying electronic media to prevent childhood obesity are contemporary. Available studies applying electronic media are however heterogeneous in terms of applied medium and duration

Antiobesity Effects of the Ethanol Extract of Laminaria japonica Areshoung in High-Fat-Diet-Induced Obese Rat

Directory of Open Access Journals (Sweden)

Woong Sun Jang

2013-01-01

Full Text Available Laminaria japonica Areshoung, a widely consumed marine vegetable, has traditionally been used in Korean maternal health. The present study investigated the antiobesity effects of Laminaria japonica Areshoung ethanol extract (LE and its molecular mechanism in high-fat-diet-induced obese rats. Six-week-old Sprague-Dawley male rats were separately fed a normal diet or a high-calorie high-fat diet for 6 weeks; then they were treated with LE or tea catechin for another 6 weeks. LE administration significantly decreased the body weight gain, fat-pad weights, and serum and hepatic lipid levels in HD-induced obese rats. The histological analysis revealed that LE-treated group showed a significantly decreased number of lipid droplets and size of adipocytes compared to the HD group. To elucidate the mechanism of action of LE, the levels of genes and proteins involved in obesity were measured in the liver and skeletal muscle. LE treatment resulted in an increased expression of fatty acid oxidation and thermogenesis-related genes in obese rats. Conversely, the expression of the fat intake-related gene (ACC2 and lipogenesis-related genes was reduced by LE treatment. Additionally, LE treatment increased the phosphorylation of AMP-activated protein kinase and its direct downstream protein, acetyl coenzyme A carboxylase, which is one of the rate-limiting enzymes in fatty acid synthesis pathway. These findings demonstrate that LE treatment has a protective effect against a high-fat-diet-induced obesity in rats through regulation of expression of genes and proteins involved in lipolysis and lipogenesis.

Administration of dried Aloe vera gel powder reduced body fat mass in diet-induced obesity (DIO) rats.

Science.gov (United States)

Misawa, Eriko; Tanaka, Miyuki; Nabeshima, Kazumi; Nomaguchi, Kouji; Yamada, Muneo; Toida, Tomohiro; Iwatsuki, Keiji

2012-01-01

The aim of the present study was to investigate the anti-obesity effects of Aloe vera gel administration in male Sprague-Dawley (SD) rats with diet-induced obesity (DIO). SD rats at 7 wk of age were fed either a standard diet (10 kcal% fat) (StdD) or high-fat (60 kcal% fat) diet (HFD) during the experimental period. Four weeks after of HFD-feeding, DIO rats (11 wk of age) were orally administered with two doses of Aloe vera gel powder (20 and 200 mg/kg/d) for 90 d. Body weights (g) and body fat (%) of HFD fed rats were significantly higher than those of StdD-fed rats. Although a modest decrease of body weight (g) was observed with the administration of dried Aloe vera gel powder, both subcutaneous and visceral fat weight (g) and body fat (%) were reduced significantly in Aloe vera gel-treated rats. Serum lipid parameters elevated by HFD were also improved by the Aloe vera gel treatment. The oxygen consumption (VO(2)), an index of energy expenditure, was decreased in HFD-fed rats compared with that in StdD-fed rats. Administration of Aloe vera gel reversed the change in VO(2) in the HFD-fed rats. These results suggest that intake of Aloe vera gel reduced body fat accumulation, in part, by stimulation of energy expenditure. Aloe vera gel might be beneficial for the prevention and improvement of diet-induced obesity.

Postnatal treatment with metyrapone attenuates the effects of diet-induced obesity in female rats exposed to early-life stress.

Science.gov (United States)

Murphy, Margaret O; Herald, Joseph B; Wills, Caleb T; Unfried, Stanley G; Cohn, Dianne M; Loria, Analia S

2017-02-01

Experimental studies in rodents have shown that females are more susceptible to exhibiting fat expansion and metabolic disease compared with males in several models of fetal programming. This study tested the hypothesis that female rat pups exposed to maternal separation (MatSep), a model of early-life stress, display an exacerbated response to diet-induced obesity compared with male rats. Also, we tested whether the postnatal treatment with metyrapone (MTP), a corticosterone synthase inhibitor, would attenuate this phenotype. MatSep was performed in WKY offspring by separation from the dam (3 h/day, postnatal days 2-14). Upon weaning, male and female rats were placed on a normal (ND; 18% kcal fat) or high-fat diet (HFD; 60% kcal fat). Nondisturbed littermates served as controls. In male rats, no diet-induced differences in body weight (BW), glucose tolerance, and fat tissue weight and morphology were found between MatSep and control male rats. However, female MatSep rats displayed increased BW gain, fat pad weights, and glucose intolerance compared with control rats (P obesity risk factors, including elevated adiposity, hyperleptinemia, and glucose intolerance. These findings show that exposure to stress hormones during early life could be a key event to enhance diet-induced obesity and metabolic disease in female rats. Thus, pharmacological and/or behavioral inflection of the stress levels is a potential therapeutic approach for prevention of early life stress-enhanced obesity and metabolic disease. Copyright © 2017 the American Physiological Society.

Relationship between lipogenesis, ketogenesis, and malonyl-CoA content in isolated hepatocytes from the obese Zucker rat adapted to a high-fat diet.

Science.gov (United States)

Malewiak, M I; Griglio, S; Le Liepvre, X

1985-07-01

The relationship between lipogenesis and ketogenesis and the concentration of malonyl coenzyme A (CoA) was investigated in hepatocytes from adult obese Zucker rats and their lean littermates fed either a control low-fat diet or a high-fat diet (30% lard in weight). With the control diet, lipogenesis--although strongly inhibited in the presence of either 1 mmol/L oleate, 10(-6) mol/L glucagon or 0.1 mmol/L TOFA (a hypolipidemic drug)--remained about fifteen-fold higher in the obese rats than in the lean rats. In contrast, ketogenesis under some conditions (oleate + TOFA) was not significantly lower (30%) as compared with the lean rats. After adaptation to the high-fat diet, lipogenesis was depressed fourfold in the lean rats and ninefold in the obese ones; however its magnitude remained significantly higher in the latter, namely at a value close to that measured in control-fed lean rats. Ketogenesis was comparable in lean and obese rats and much higher in the presence of 1 mmol/L oleate than of 0.3 mmol/L oleate, whereas lipogenesis did not vary with increasing oleate concentration in the medium. Acetyl-CoA carboxylase activity measured in liver homogenates was higher in the obese group, but was stepwise inhibited by increasing concentrations of oleyl-CoA regardless of the diet for both lean and obese rats, thus showing no abnormality of in vitro responsiveness to this inhibitor. With the control diet, hepatocyte malonyl-CoA levels were significantly higher in the obese rats, both in the basal state and after inhibition of lipogenesis by oleate and TOFA.(ABSTRACT TRUNCATED AT 250 WORDS)

Four-Week Consumption of Malaysian Honey Reduces Excess Weight Gain and Improves Obesity-Related Parameters in High Fat Diet Induced Obese Rats

OpenAIRE

Suhana Samat; Francis Kanyan Enchang; Fuzina Nor Hussein; Wan Iryani Wan Ismail

2017-01-01

Many studies revealed the potential of honey consumption in controlling obesity. However, no study has been conducted using Malaysian honey. In this study, we investigated the efficacy of two local Malaysian honey types: Gelam and Acacia honey in reducing excess weight gain and other parameters related to obesity. The quality of both honey types was determined through physicochemical analysis and contents of phenolic and flavonoid. Male Sprague-Dawley rats were induced to become obese using h...

Electronic health records to support obesity-related patient care: Results from a survey of United States physicians.

Science.gov (United States)

Bronder, Kayla L; Dooyema, Carrie A; Onufrak, Stephen J; Foltz, Jennifer L

2015-08-01

Obesity-related electronic health record functions increase the rates of measuring Body Mass Index, diagnosing obesity, and providing obesity services. This study describes the prevalence of obesity-related electronic health record functions in clinical practice and analyzes characteristics associated with increased obesity-related electronic health record sophistication. Data were analyzed from DocStyles, a web-based panel survey administered to 1507 primary care providers practicing in the United States in June, 2013. Physicians were asked if their electronic health record has specific obesity-related functions. Logistical regression analyses identified characteristics associated with improved obesity-related electronic health record sophistication. Of the 88% of providers with an electronic health record, 83% of electronic health records calculate Body Mass Index, 52% calculate pediatric Body Mass Index percentile, and 32% flag patients with abnormal Body Mass Index values. Only 36% provide obesity-related decision support and 17% suggest additional resources for obesity-related care. Characteristics associated with having a more sophisticated electronic health record include age ≤45years old, being a pediatrician or family practitioner, and practicing in a larger, outpatient practice. Few electronic health records optimally supported physician's obesity-related clinical care. The low rates of obesity-related electronic health record functions currently in practice highlight areas to improve the clinical health information technology in primary care practice. More work can be done to develop, implement, and promote the effective utilization of obesity-related electronic health record functions to improve obesity treatment and prevention efforts. Published by Elsevier Inc.

Evaluation of anti-obesity activity of duloxetine in comparison with sibutramine along with its anti-depressant activity: an experimental study in obese rats.

Science.gov (United States)

Chudasama, H P; Bhatt, P A

2009-11-01

5-HT and noradrenaline are important neurotransmitters that control increase in body mass and are involved in the pathophysiology of obesity and depression. Sibutramine, an established anti-obesity agent, and duloxetine, an anti-depressant agent, are serotonin noradrenaline reuptake inhibitors (SNRIs). The objective of the present study was to compare the anti-obesity effect of duloxetine with sibutramine along with its effect on blood pressure and depression in obese rats. The secondary objective of the study was to determine if a relationship exists between obesity and depression. Obesity was induced by high-fat diet (HFD) in healthy male Sprague-Dawley rats. After 5 weeks of feeding HFD, animals were overweight (17.57%) with high food intake (57.15%) in comparison with normal animals. These obese animals were treated with duloxetine (30 mg x kg(-1), p.o.) and sibutramine (5 mg x kg(-1), p.o.) for 4 weeks. Control animals were treated with duloxetine alone (30 mg x kg(-1), p.o.). Our results depict that duloxetine was as effective as sibutramine in reducing food intake, body mass, and relative adiposity, and increasing rectal temperature with an added advantage of decreasing blood pressure, which sibutramine failed to do. Besides reduction in body mass, unlike sibutramine, duloxetine improved depressive state as evaluated by despair swimming test, tail suspension test, and open field test, speculating its use as an anti-obesity agent in obese-depressive animals. Since obese control animals reflected decreased locomotor activity, a positive relationship can be speculated to exist between obesity and depression. Further studies on various antidepressant models are required to confirm this relationship.

High dietary fat-induced obesity in Wistar rats and type 2 diabetes in nonobese Goto-Kakizaki rats differentially affect retinol binding protein 4 expression and vitamin A metabolism.

Science.gov (United States)

Shirai, Tomomi; Shichi, Yuta; Sato, Miyuki; Tanioka, Yuri; Furusho, Tadasu; Ota, Toru; Tadokoro, Tadahiro; Suzuki, Tsukasa; Kobayashi, Ken-Ichi; Yamamoto, Yuji

2016-03-01

Obesity is a major risk factor for type 2 diabetes, which is caused mainly by insulin resistance. Retinol binding protein 4 (RBP4) is the only specific transport protein for retinol in the serum. RBP4 level is increased in the diabetic state and high-fat condition, indicating that retinol metabolism may be affected under these conditions. However, the precise effect of diabetes and high fat-induced obesity on retinol metabolism is unknown. In this study, we examined differences in retinol metabolite levels in rat models of diet-induced obesity and type 2 diabetes (Goto-Kakizaki [GK] rat). Four-week-old male Wistar and GK rats were given either a control diet (AIN-93G) or a high-fat diet (HFD, 40% fat kJ). After 15 weeks of feeding, the RBP4 levels increased by 2-fold in the serum of GK rats but not HFD-fed rats. The hepatic retinol concentration of HFD-fed rats was approximately 50% that of the controls (P type 2 diabetes mellitus. Copyright © 2016 Elsevier Inc. All rights reserved.

Investigation of brain-derived neurotrophic factor (BDNF) gene expression in hypothalamus of obese rats: Modulation by omega-3 fatty acids.

Science.gov (United States)

Abdel-Maksoud, Sahar M; Hassanein, Sally I; Gohar, Neveen A; Attia, Saad M M; Gad, Mohamed Z

2017-10-01

The aim of this study was investigating the effect of omega-3 fatty acids (ω-3 FAs) on brain-derived neurotrophic factor (BDNF) gene expression, using in vivo and in vitro models, to unravel the potential mechanisms of polyunsaturated fatty acids use in obesity. Twenty-nine Sprague-Dawley rats were divided into three groups; lean controls fed normal chow diet for 14 weeks, obese controls fed 60% of their diet as saturated fats for 14 weeks, and ω-3 FAs-treated rats fed 60% saturated fat diet for 14 weeks with concomitant oral administration of 400 mg/kg/day ω-3 FAs, mainly docosahexaenoic acid and EPA, from week 12 to week 14. For the in vitro experiment, hypothalamic cells from six obese rats were cultured in the presence of different concentrations of ω-3 FAs to determine its direct effect on BDNF expression. In vivo results showed that obesity has negative effect on BDNF gene expression in rat hypothalamus that was reversed by administration of ω-3 FAs. Obese rats showed hypercholesterolemia, hypertriglyceridemia, normoinsulinemia, hyperglycemia and hyperleptinemia. Treatment with ω-3 FAs showed significant decrease in serum total cholesterol and TAG. Also serum glucose level and HOMA index were decreased significantly. In vitro results demonstrated the increase in BDNF expression by ω-3 FAs in a dose-dependent manner. Obesity causes down-regulation of BDNF gene expression that can be reversed by ω-3 FAs treatment, making them an interesting treatment approach for obesity and metabolic disease.

Cerebral markers of the serotonergic system in rat models of obesity and after Roux-en-Y gastric bypass

DEFF Research Database (Denmark)

Ratner, Cecilia; Ettrup, Anders; Bueter, Marco

2012-01-01

Food intake and body weight are regulated by a complex system of neural and hormonal signals, of which the anorexigenic neurotransmitter serotonin (5-hydroxytryptamine or 5-HT) is central. In this study, rat models of obesity and weight loss intervention were compared with regard to several 5-HT......DIO as compared to pgDR rats corresponds to what is reported in overweight humans and suggests that the dysfunctions of the 5-HT system associated with overeating or propensity to become overweight are polygenically determined. Our results support that the obesity-prone rat model has high translational value...... and suggests that susceptibility to develop obesity is associated with changed 5-HT tone in the brain that may also regulate hedonic aspects of feeding....

High-protein diet selectively reduces fat mass and improves glucose tolerance in Western-type diet-induced obese rats

Science.gov (United States)

Stengel, Andreas; Goebel-Stengel, Miriam; Wang, Lixin; Hu, Eugenia; Karasawa, Hiroshi; Pisegna, Joseph R.

2013-01-01

Obesity is an increasing health problem. Because drug treatments are limited, diets remain popular. High-protein diets (HPD) reduce body weight (BW), although the mechanisms are unclear. We investigated physiological mechanisms altered by switching diet induced obesity (DIO) rats from Western-type diet (WTD) to HPD. Male rats were fed standard (SD) or WTD (45% calories from fat). After developing DIO (50% of rats), they were switched to SD (15% calories from protein) or HPD (52% calories from protein) for up to 4 weeks. Food intake (FI), BW, body composition, glucose tolerance, insulin sensitivity, and intestinal hormone plasma levels were monitored. Rats fed WTD showed an increased FI and had a 25% greater BW gain after 9 wk compared with SD (P Diet-induced obese rats switched from WTD to HPD reduced daily FI by 30% on day 1, which lasted to day 9 (−9%) and decreased BW during the 2-wk period compared with SD/SD (P < 0.05). During these 2 wk, WTD/HPD rats lost 72% more fat mass than WTD/SD (P < 0.05), whereas lean mass was unaltered. WTD/HPD rats had lower blood glucose than WTD/SD at 30 min postglucose gavage (P < 0.05). The increase of pancreatic polypeptide and peptide YY during the 2-h dark-phase feeding was higher in WTD/HPD compared with WTD/SD (P < 0.05). These data indicate that HPD reduces BW in WTD rats, which may be related to decreased FI and the selective reduction of fat mass accompanied by improved glucose tolerance, suggesting relevant benefits of HPD in the treatment of obesity. PMID:23883680

Roux-en-Y gastric bypass surgery suppresses hypothalamic PTP1B protein level and alleviates leptin resistance in obese rats.

Science.gov (United States)

Liu, Jia-Yu; Mu, Song; Zhang, Shu-Ping; Guo, Wei; Li, Qi-Fu; Xiao, Xiao-Qiu; Zhang, Jun; Wang, Zhi-Hong

2017-09-01

The present study aimed to explore the effect of Roux-en-Y gastric bypass (RYGB) surgery on protein tyrosine phosphatase 1B (PTP1B) expression levels and leptin activity in hypothalami of obese rats. Obese rats induced by a high-fat diet (HFD) that underwent RYGB (n=11) or sham operation (SO, n=9), as well as an obese control cohort (Obese, n=10) and an additional normal-diet group (ND, n=10) were used. Food efficiency was measured at 8 weeks post-operation. Plasma leptin levels were evaluated and hypothalamic protein tyrosine phosphatase 1B (PTP1B) levels and leptin signaling activity were examined at the genetic and protein levels. The results indicated that food efficiency was typically lower in RYGB rats compared with that in the Obese and SO rats. In the RYGB group, leptin receptor expression and proopiomelanocortin was significantly higher, while Neuropeptide Y levels were lower than those in the Obese and SO groups. Furthermore, the gene and protein expression levels of PTP1B in the RYGB group were lower, while levels of phosphorylated signal transducer and activator of transcription 3 protein were much higher compared with those in the Obese and SO groups. In conclusion, RYGB surgery significantly suppressed hypothalamic PTP1B protein expression. PTP1B regulation may partially alleviate leptin resistance.

Maternal obesity during gestation impairs fatty acid oxidation and mitochondrial SIRT3 expression in rat offspring at weaning.

Directory of Open Access Journals (Sweden)

Sarah J Borengasser

Full Text Available In utero exposure to maternal obesity increases the offspring's risk of obesity in later life. We have also previously reported that offspring of obese rat dams develop hepatic steatosis, mild hyperinsulinemia, and a lipogenic gene signature in the liver at postnatal day (PND21. In the current study, we examined systemic and hepatic adaptations in male Sprague-Dawley offspring from lean and obese dams at PND21. Indirect calorimetry revealed decreases in energy expenditure (p<0.001 and increases in RER values (p<0.001, which were further exacerbated by high fat diet (45% kcals from fat consumption indicating an impaired ability to utilize fatty acids in offspring of obese dams as analyzed by PRCF. Mitochondrial function is known to be associated with fatty acid oxidation (FAO in the liver. Several markers of hepatic mitochondrial function were reduced in offspring of obese dams. These included SIRT3 mRNA (p = 0.012 and mitochondrial protein content (p = 0.002, electron transport chain complexes (II, III, and ATPase, and fasting PGC-1α mRNA expression (p<0.001. Moreover, hepatic LCAD, a SIRT3 target, was not only reduced 2-fold (p<0.001 but was also hyperacetylated in offspring of obese dams (p<0.005 suggesting decreased hepatic FAO. In conclusion, exposure to maternal obesity contributes to early perturbations in whole body and liver energy metabolism. Mitochondrial dysfunction may be an underlying event that reduces hepatic fatty acid oxidation and precedes the development of detrimental obesity associated co-morbidities such as insulin resistance and NAFLD.

Xanthohumol lowers body weight and fasting plasma glucose in obese male Zucker fa/fa rats.

Science.gov (United States)

Legette, Leecole L; Luna, Arlyn Y Moreno; Reed, Ralph L; Miranda, Cristobal L; Bobe, Gerd; Proteau, Rosita R; Stevens, Jan F

2013-07-01

Obesity contributes to increased risk for several chronic diseases including cardiovascular disease and type 2 diabetes. Xanthohumol, a prenylated flavonoid from hops (Humulus lupulus), was tested for efficacy on biomarkers of metabolic syndrome in 4 week old Zucker fa/fa rats, a rodent model of obesity. Rats received daily oral doses of xanthohumol at 0, 1.86, 5.64, and 16.9 mg/kg BW for 6 weeks. All rats were maintained on a high fat (60% kcal) AIN-93G diet for 3 weeks to induce severe obesity followed by a normal AIN-93G (15% kcal fat) diet for the last 3 weeks of the study. Weekly food intake and body weight were recorded. Plasma cholesterol, glucose, insulin, triglyceride, and monocyte chemoattractant protein-1 (MCP-1) levels were assessed using commercial assay kits. Plasma and liver tissue levels of XN and its metabolites were determined by liquid-chromatography tandem mass spectrometry. Plasma and liver tissue levels of xanthohumol were similar between low and medium dose groups and significantly (peffect on body weight and plasma glucose levels. The highest dose group (n=6) had significantly lower plasma glucose levels compared to the control group (n=6) in male but not female rats. There was also a significant decrease in body weight for male rats in the highest dose group (16.9 mg/kg BW) compared to rats that received no xanthohumol, which was also not seen for female rats. Plasma cholesterol, insulin, triglycerides, and MCP-1 as well as food intake were not affected by treatment. The findings suggest that xanthohumol has beneficial effects on markers of metabolic syndrome. Copyright © 2012. Published by Elsevier Ltd.

Effect of feeding a high-fat diet independently of caloric intake on reproductive function in diet-induced obese female rats

Science.gov (United States)

Hussain, Mona A.; Abogresha, Noha M.; Tamany, Dalia A.; Lotfy, Mariam

2016-01-01

Introduction Globally, the prevalence of overweight and obesity is increasing, predisposing females to health hazards including compromised reproductive capacity. Our objective was to investigate the effect of ad libitum, isocalorically and hypocalorically restricted high-fat diet (HFD) feeding on reproductive function in diet-induced obese female rats. Material and methods Twenty female albino Sprague Dawley rats were used; 5 rats were kept on a standard pellet animal diet to serve as a control group (A) and 15 rats were fed a HFD for 9 weeks to induce obesity. The HFD fed animals were equally divided into three groups: an ad libitum HFD group (B), an isocalorically restricted HFD group (C), and a hypocalorically restricted HFD group (D). Estrous cyclicity, hormonal levels, ovarian histopathology and caspase-3 immunoreactivity were evaluated. Results The HFD-fed rats in groups B, C and D had significant irregularity in estrous cyclicity Vs group A (p = 0.001, 0.003 and 0.034 respectively). Groups C and D had significant reduction in serum progesterone level (p = 0.006 and 0.018 Vs A). Isocaloric restriction of HFD feeding significantly increased serum LH. Groups B and C had a significant increase in caspase-3 expression in the ovary (p < 0.001). Conclusions Ad libitum HFD interfered with the normal estrous cycle and enhanced apoptosis of luteal cells in obese female rats. The HFD restriction interfered with the normal estrous cycle and caused functional insufficiency of the corpus luteum in obese female rats. These results suggest that HFD feeding determinately affects female reproductive function independently of caloric intake. PMID:27478474

The impact of obesity in the cardiac lipidome and its consequences in the cardiac damage observed in obese rats.

Science.gov (United States)

Marín-Royo, Gema; Martínez-Martínez, Ernesto; Gutiérrez, Beatriz; Jurado-López, Raquel; Gallardo, Isabel; Montero, Olimpio; Bartolomé, Mª Visitación; Román, José Alberto San; Salaices, Mercedes; Nieto, María Luisa; Cachofeiro, Victoria

To explore the impact of obesity on the cardiac lipid profile in rats with diet-induced obesity, as well as to evaluate whether or not the specific changes in lipid species are associated with cardiac fibrosis. Male Wistar rats were fed either a high-fat diet (HFD, 35% fat) or standard diet (3.5% fat) for 6 weeks. Cardiac lipids were analyzed using by liquid chromatography-tandem mass spectrometry. HFD rats showed cardiac fibrosis and enhanced levels of cardiac superoxide anion (O 2 ), HOMA index, adiposity, and plasma leptin, as well as a reduction in those of cardiac glucose transporter (GLUT 4), compared with control animals. Cardiac lipid profile analysis showed a significant increase in triglycerides, especially those enriched with palmitic, stearic, and arachidonic acid. An increase in levels of diacylglycerol (DAG) was also observed. No changes in cardiac levels of diacyl phosphatidylcholine, or even a reduction in total levels of diacyl phosphatidylethanolamine, diacyl phosphatidylinositol, and sphingomyelins (SM) was observed in HFD, as compared with control animals. After adjustment for other variables (oxidative stress, HOMA, cardiac hypertrophy), total levels of DAG were independent predictors of cardiac fibrosis while the levels of total SM were independent predictors of the cardiac levels of GLUT 4. These data suggest that obesity has a significant impact on cardiac lipid composition, although it does not modulate the different species in a similar manner. Nonetheless, these changes are likely to participate in the cardiac damage in the context of obesity, since total DAG levels can facilitate the development of cardiac fibrosis, and SM levels predict GLUT4 levels. Copyright © 2017 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.

Obesity and type 2 diabetes in rats are associated with altered brain glycogen and amino-acid homeostasis

DEFF Research Database (Denmark)

Sickmann, Helle M; Waagepetersen, Helle S; Schousboe, Arne

2010-01-01

Obesity and type 2 diabetes have reached epidemic proportions; however, scarce information about how these metabolic syndromes influence brain energy and neurotransmitter homeostasis exist. The objective of this study was to elucidate how brain glycogen and neurotransmitter homeostasis are affected...... by these conditions. [1-(13)C]glucose was administered to Zucker obese (ZO) and Zucker diabetic fatty (ZDF) rats. Sprague-Dawley (SprD), Zucker lean (ZL), and ZDF lean rats were used as controls. Several brain regions were analyzed for glycogen levels along with (13)C-labeling and content of glutamate, glutamine...... of glutamine and glutamate were decreased in the cerebellum of the ZO and the ZDF rats. Glycogen levels were also lower in this region. These results suggest that the obese and type 2 diabetic models were associated with lower brain glucose metabolism. Glucose metabolism through the TCA cycle was more...

Roux-en-Y gastric bypass increases intravenous ethanol self-administration in dietary obese rats.

Directory of Open Access Journals (Sweden)

James E Polston

Full Text Available Roux-en-Y gastric bypass surgery (RYGB is an effective treatment for severe obesity. Clinical studies however have reported susceptibility to increased alcohol use after RYGB, and preclinical studies have shown increased alcohol intake in obese rats after RYGB. This could reflect a direct enhancement of alcohol's rewarding effects in the brain or an indirect effect due to increased alcohol absorption after RGYB. To rule out the contribution that changes in alcohol absorption have on its rewarding effects, here we assessed the effects of RYGB on intravenously (IV administered ethanol (1%. For this purpose, high fat (60% kcal from fat diet-induced obese male Sprague Dawley rats were tested ~2 months after RYGB or sham surgery (SHAM using both fixed and progressive ratio schedules of reinforcement to evaluate if RGYB modified the reinforcing effects of IV ethanol. Compared to SHAM, RYGB rats made significantly more active spout responses to earn IV ethanol during the fixed ratio schedule, and achieved higher breakpoints during the progressive ratio schedule. Although additional studies are needed, our results provide preliminary evidence that RYGB increases the rewarding effects of alcohol independent of its effects on alcohol absorption.

Effects of proportions of dietary macronutrients on glucocorticoid metabolism in diet-induced obesity in rats.

Directory of Open Access Journals (Sweden)

Roland H Stimson

2010-01-01

Full Text Available Tissue glucocorticoid levels in the liver and adipose tissue are regulated by regeneration of inactive glucocorticoid by 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1 and inactivation by 5alpha- and 5beta-reductases. A low carbohydrate diet increases hepatic 11beta-HSD1 and reduces glucocorticoid metabolism during weight loss in obese humans. We hypothesized that similar variations in macronutrient proportions regulate glucocorticoid metabolism in obese rats. Male Lister Hooded rats were fed an obesity-inducing ad libitum 'Western' diet (37% fat, n = 36 for 22 weeks, then randomised to continue this diet (n = 12 or to switch to either a low carbohydrate (n = 12 or a moderate carbohydrate (n = 12 diet for the final 8 weeks. A parallel lean control group were fed an ad libitum control diet (10% fat, n = 12 throughout. The low and moderate carbohydrate diets decreased hepatic 11beta-HSD1 mRNA compared with the Western diet (both 0.7+/-0.0 vs 0.9+/-0.1 AU; p<0.01, but did not alter 11beta-HSD1 in adipose tissue. 5Alpha-reductase mRNA was increased on the low carbohydrate compared with the moderate carbohydrate diet. Compared with lean controls, the Western diet decreased 11beta-HSD1 activity (1.6+/-0.1 vs 2.8+/-0.1 nmol/mcg protein/hr; p<0.001 and increased 5alpha-reductase and 5beta-reductase mRNAs (1.9+/-0.3 vs 1.0+/-0.2 and 1.6+/-0.1 vs 1.0+/-0.1 AU respectively; p<0.01 in the liver, and reduced 11beta-HSD1 mRNA and activity (both p<0.01 in adipose tissue. Although an obesity-inducing high fat diet in rats recapitulates the abnormal glucocorticoid metabolism associated with human obesity in liver (but not in adipose tissue, a low carbohydrate diet does not increase hepatic 11beta-HSD1 in obese rats as occurs in humans.

Hypocaloric high-protein diet improves fatty liver and hypertriglyceridemia in sucrose-fed obese rats via two pathways.

Science.gov (United States)

Uebanso, Takashi; Taketani, Yutaka; Fukaya, Makiko; Sato, Kazusa; Takei, Yuichiro; Sato, Tadatoshi; Sawada, Naoki; Amo, Kikuko; Harada, Nagakatsu; Arai, Hidekazu; Yamamoto, Hironori; Takeda, Eiji

2009-07-01

The mechanism by which replacement of some dietary carbohydrates with protein during weight loss favors lipid metabolism remains obscure. In this study, we investigated the effect of an energy-restricted, high-protein/low-carbohydrate diet on lipid metabolism in obese rats. High-sucrose-induced obese rats were assigned randomly to one of two energy-restricted dietary interventions: a carbohydrate-based control diet (CD) or a high-protein diet (HPD). Lean rats of the same age were assigned as normal control. There was significantly greater improvement in fatty liver and hypertriglyceridemia with the HPD diet relative to the CD diet. Expression of genes regulated by fibroblast growth factor-21 (FGF21) and involved in liver lipolysis and lipid utilitization, such as lipase and acyl-CoA oxidase, increased in obese rats fed the HPD. Furthermore, there was an inverse correlation between levels of FGF21 gene expression (regulated by glucagon/insulin balance) and increased triglyceride concentrations in liver from obese rats. Expression of hepatic stearoyl-CoA desaturase-1 (SCD1), regulated primarily by the dietary carbohydrate, was also markedly reduced in the HPD group (similar to plasma triglyceride levels in fasting animals) relative to the CD group. In conclusion, a hypocaloric high-protein diet improves fatty liver and hypertriglyceridemia effectively relative to a carbohydrate diet. The two cellular pathways at work behind these benefits include stimulation of hepatic lipolysis and lipid utilization mediated by FGF21 and reduction of hepatic VLDL-TG production by SCD1 regulation.

Obesity reduces bone density through activation of PPAR gamma and suppression of Wnt/Beta-Catenin in rapidly growing male rats

Science.gov (United States)

The relationship between obesity and skeletal development remains largely ambiguous. In this report, total enteral nutrition (TEN) was used to feed growing male rats intragastrically, with a high 45% fat diet (HFD) to induce obesity. We found that fat mass was increased (P<0.05) compared to rats fed...

Polyphenol-Rich Extract of Syzygium cumini Leaf Dually Improves Peripheral Insulin Sensitivity and Pancreatic Islet Function in Monosodium L-Glutamate-Induced Obese Rats

Science.gov (United States)

Sanches, Jonas R.; França, Lucas M.; Chagas, Vinicyus T.; Gaspar, Renato S.; dos Santos, Kayque A.; Gonçalves, Luciana M.; Sloboda, Deborah M.; Holloway, Alison C.; Dutra, Richard P.; Carneiro, Everardo M.; Cappelli, Ana Paula G.; Paes, Antonio Marcus de A.

2016-01-01

Syzygium cumini (L.) Skeels (Myrtaceae) has been traditionally used to treat a number of illnesses. Ethnopharmacological studies have particularly addressed antidiabetic and metabolic-related effects of extracts prepared from its different parts, especially seed, and pulp-fruit, however. there is a lack of studies on phytochemical profile and biological properties of its leaf. As there is considerable interest in bioactive compounds to treat metabolic syndrome and its clustered risk factors, we sought to characterize the metabolic effects of hydroethanolic extract of S. cumini leaf (HESc) on lean and monosodium L-glutamate (MSG)-induced obese rats. HPLC-MS/MS characterization of the HESc polyphenolic profile, at 254 nm, identified 15 compounds pertaining to hydrolysable tannin and flavanol subclasses. At 60 days of age, both groups were randomly assigned to receive HESc (500 mg/kg) or vehicle for 30 days. At the end of treatment, obese+HESc exhibited significantly lower body weight gain, body mass index, and white adipose tissue mass, compared to obese rats receiving vehicle. Obese rats treated with HESc showed a twofold increase in lipolytic activity in the periepididymal fat pad, as well as, brought triglyceride levels in serum, liver and skeletal muscle back to levels close those found in lean animals. Furthermore, HESc also improved hyperinsulinemia and insulin resistance in obese+HESc rats, which resulted in partial reversal of glucose intolerance, as compared to obese rats. HESc had no effect in lean rats. Assessment of ex vivo glucose-stimulated insulin secretion showed HESc potentiated pancreatic function in islets isolated from both lean and obese rats treated with HESc. In addition, HESc (10–1000 μg/mL) increased glucose stimulated insulin secretion from both isolated rat islets and INS-1E β-cells. These data demonstrate that S. cumini leaf improved peripheral insulin sensitivity via stimulating/modulating β-cell insulin release, which was associated

Polyphenol-rich extract of Syzygium cumini leaf dually improves peripheral insulin sensitivity and pancreatic islet function in monosodium L-glutamate-induced obese rats

Directory of Open Access Journals (Sweden)

Jonas Rodrigues Sanches

2016-03-01

Full Text Available Syzygium cumini (L. Skeels (Myrtaceae has been traditionally used to treat a number of illnesses. Ethnopharmacological studies have particularly addressed antidiabetic and metabolic-related effects of extracts prepared from its different parts, especially seed and pulp-fruit, however there is a lack of studies on phytochemical profile and biological properties of its leaf. As there is considerable interest in bioactive compounds to treat metabolic syndrome and its clustered risk factors, we sought to characterize the metabolic effects of hydroethanolic extract of S. cumini leaf (HESc on lean and monosodium L-glutamate (MSG-induced obese rats. HPLC-MS/MS characterization of the HESc polyphenolic profile, at 254 nm, identified 15 compounds pertaining to hydrolysable tannin and flavanol subclasses. At 60 days of age, both groups were randomly assigned to receive HESc (500 mg/kg or vehicle for 30 days. At the end of treatment, obese+HESc exhibited significantly lower body weight gain, body mass index, and white adipose tissue mass, compared to obese rats receiving vehicle. Obese rats treated with HESc showed a 2-fold increase in lipolytic activity in the periepididymal fat pad, as well as, brought triglyceride levels in serum, liver and skeletal muscle back to levels close those found in lean animals. Furthermore, HESc also improved hyperinsulinemia and insulin resistance in obese+HESc rats, which resulted in partial reversal of glucose intolerance, as compared to obese rats. HESc had no effect in lean rats. Assessment of ex vivo glucose-stimulated insulin secretion showed HESc potentiated pancreatic function in islets isolated from both lean and obese rats treated with HESc. In addition, HESc (10 – 1000 ug/mL increased glucose stimulated insulin secretion from both isolated rat islets and INS-1E beta cells. These data demonstrate that S. cumini leaf improved peripheral insulin sensitivity via stimulating/modulating beta cell insulin release

Hormonal control of fat accumulation in L-glutamate-treated obese rats

International Nuclear Information System (INIS)

Remke, H.; Wilsdorf, A.; Mueller, F.

1988-01-01

Persistently decreased concentrations of the growth hormone and the tissue-nonepinephrine in connection with growth retardation and obesity were investigated concerning the effects on cells of epididymal adipose tissue in postnatally injured glutamate-treated rats using 14 C-labelled tracers. Diminished secretion of growth hormone causes in adipocytes increased glucose intake, amplification of the insulin effect, and fat accumulation. A supersensitivity towards norepinephrine in adipocytes in vitro is due to diminished concentration of this hormone in the tissue. Insulin resistance is developed at the beginning of the stationary phase of obesity in these animals. (author)

High-fat diet-induced plasma protein and liver changes in obese rats can be attenuated by melatonin supplementation.

Science.gov (United States)

Wongchitrat, Prapimpun; Klosen, Paul; Pannengpetch, Supitcha; Kitidee, Kuntida; Govitrapong, Piyarat; Isarankura-Na-Ayudhya, Chartchalerm

2017-06-01

Obesity triggers changes in protein expression in various organs that might participate in the pathogenesis of obesity. Melatonin has been reported to prevent or attenuate such pathological protein changes in several chronic diseases. However, such melatonin effects on plasma proteins have not yet been studied in an obesity model. Using a proteomic approach, we investigated the effect of melatonin on plasma protein profiles after rats were fed a high-fat diet (HFD) to induce obesity. We hypothesized that melatonin would attenuate abnormal protein expression in obese rats. After 10weeks of the HFD, animals displayed increased body weight and fat accumulation as well as increased glucose levels, indicating an obesity-induced prediabetes mellitus-like state. Two-dimensional gel electrophoresis and liquid chromatography-mass spectrometry/mass spectrometry revealed 12 proteins whose expression was altered in response to the HFD and the melatonin treatment. The altered proteins are related to the development of liver pathology, such as cirrhosis (α1-antiproteinase), thrombosis (fibrinogen, plasminogen), and inflammation (mannose-binding protein A, complement C4, complement factor B), contributing to liver steatosis or hepatic cell death. Melatonin treatment most probably reduced the severity of the HFD-induced obesity by reducing the amplitude of HFD-induced plasma protein changes. In conclusion, we identified several potential biomarkers associated with the progression of obesity and its complications, such as liver damage. Furthermore, our findings reveal melatonin's beneficial effect of attenuating plasma protein changes and liver pathogenesis in obese rats. Copyright © 2017 Elsevier Inc. All rights reserved.

Anti-Diabetic Activity and Metabolic Changes Induced by Andrographis paniculata Plant Extract in Obese Diabetic Rats

Directory of Open Access Journals (Sweden)

Muhammad Tayyab Akhtar

2016-08-01

Full Text Available Andrographis paniculata is an annual herb and widely cultivated in Southeast Asian countries for its medicinal use. In recent investigations, A. paniculata was found to be effective against Type 1 diabetes mellitus (Type 1 DM. Here, we used a non-genetic out-bred Sprague-Dawley rat model to test the antidiabetic activity of A. paniculata against Type 2 diabetes mellitus (Type 2 DM. Proton Nuclear Magnetic Resonance (1H-NMR spectroscopy in combination with multivariate data analyses was used to evaluate the A. paniculata and metformin induced metabolic effects on the obese and obese–diabetic (obdb rat models. Compared to the normal rats, high levels of creatinine, lactate, and allantoin were found in the urine of obese rats, whereas, obese-diabetic rats were marked by high glucose, choline and taurine levels, and low lactate, formate, creatinine, citrate, 2-oxoglutarate, succinate, dimethylamine, acetoacetate, acetate, allantoin and hippurate levels. Treatment of A. paniculata leaf water extract was found to be quite effective in restoring the disturbed metabolic profile of obdb rats back towards normal conditions. Thisstudy shows the anti-diabetic potential of A. paniculata plant extract and strengthens the idea of using this plant against the diabetes. Further classical genetic methods and state of the art molecular techniques could provide insights into the molecular mechanisms involved in the pathogenesis of diabetes mellitus and anti-diabetic effects of A. paniculata water extract.

Effect of Carnitine and herbal mixture extract on obesity induced by high fat diet in rats.

Science.gov (United States)

Amin, Kamal A; Nagy, Mohamed A

2009-10-16

Obesity-associated type 2 diabetes is rapidly increasing throughout the world. It is generally recognized that natural products with a long history of safety can modulate obesity. To investigate the development of obesity in response to a high fat diet (HFD) and to estimate the effect of L-carnitine and an Egyptian Herbal mixture formulation (HMF) (consisting of T. chebula, Senae, rhubarb, black cumin, aniseed, fennel and licorice) on bodyweight, food intake, lipid profiles, renal, hepatic, cardiac function markers, lipid Peroxidation, and the glucose and insulin levels in blood and liver tissue in rats. White male albino rats weighing 80-90 gm, 60 days old. 10 rats were fed a normal basal diet (Cr), 30 rats fed a high-fat diet (HFD) for 14 weeks during the entire study. Rats of the HFD group were equally divided into 3 subgroups each one include 10 rats. The first group received HFD with no supplement (HFD), the 2nd group HFD+L-carnitine and the third group received HFD+HMF. Carnitine and HMF were administered at 10th week (start time for treatments) for 4 weeks.Body weight, lipid profile & renal function (urea, uric acid creatinine) ALT & AST activities, cardiac markers, (LDH, C.K-NAC and MB) the oxidative stress marker reduced glutathione (GSH), and Malondialdehyde (MDA) catalase activity, in addition to glucose, insulin, and insulin resistance in serum & tissues were analyzed. Data showed that feeding HFD diet significantly increased final body weight, triglycerides (TG), total cholesterol, & LDL concentration compared with controls, while significantly decreasing HDL; meanwhile treatment with L-carnitine, or HMF significantly normalized the lipid profile.Serum ALT, urea, uric acid, creatinine, LDH, CK-NAC, CK-MB were significantly higher in the high fat group compared with normal controls; and administration of L-carnitine or herbal extract significantly lessened the effect of the HFD. Hyperglycemia, hyperinsulinemia, and high insulin resistance (IR

Effect of Carnitine and herbal mixture extract on obesity induced by high fat diet in rats

Directory of Open Access Journals (Sweden)

Amin Kamal A

2009-10-01

Full Text Available Abstract Background Obesity-associated type 2 diabetes is rapidly increasing throughout the world. It is generally recognized that natural products with a long history of safety can modulate obesity. Aim To investigate the development of obesity in response to a high fat diet (HFD and to estimate the effect of L-carnitine and an Egyptian Herbal mixture formulation (HMF (consisting of T. chebula, Senae, rhubarb, black cumin, aniseed, fennel and licorice on bodyweight, food intake, lipid profiles, renal, hepatic, cardiac function markers, lipid Peroxidation, and the glucose and insulin levels in blood and liver tissue in rats. Method White male albino rats weighing 80-90 gm, 60 days old. 10 rats were fed a normal basal diet (Cr, 30 rats fed a high-fat diet (HFD for 14 weeks during the entire study. Rats of the HFD group were equally divided into 3 subgroups each one include 10 rats. The first group received HFD with no supplement (HFD, the 2nd group HFD+L-carnitine and the third group received HFD+HMF. Carnitine and HMF were administered at 10th week (start time for treatments for 4 weeks. Body weight, lipid profile & renal function (urea, uric acid creatinine ALT & AST activities, cardiac markers, (LDH, C.K-NAC and MB the oxidative stress marker reduced glutathione (GSH, and Malondialdehyde (MDA catalase activity, in addition to glucose, insulin, and insulin resistance in serum & tissues were analyzed. Results Data showed that feeding HFD diet significantly increased final body weight, triglycerides (TG, total cholesterol, & LDL concentration compared with controls, while significantly decreasing HDL; meanwhile treatment with L-carnitine, or HMF significantly normalized the lipid profile. Serum ALT, urea, uric acid, creatinine, LDH, CK-NAC, CK-MB were significantly higher in the high fat group compared with normal controls; and administration of L-carnitine or herbal extract significantly lessened the effect of the HFD. Hyperglycemia

Obesity improves myocardial ischaemic tolerance and RISK signalling in insulin-insensitive rats

Directory of Open Access Journals (Sweden)

Daniel Donner

2013-03-01

Obesity with associated metabolic disturbances worsens ischaemic heart disease outcomes, and rodent studies confirm that obesity with insulin-resistance impairs myocardial resistance to ischemia-reperfusion (I-R injury. However, the effects of obesity per se are unclear, with some evidence for paradoxic cardioprotection (particularly in older subjects. We tested the impact of dietary obesity on I-R tolerance and reperfusion injury salvage kinase (RISK signalling in hearts from middle-aged (10 months old insulin-insensitive rats. Hearts from Wistar rats on either a 32-week control (CD or high carbohydrate obesogenic (OB diet were assessed for I-R resistance in vivo (45 minutes left anterior descending artery occlusion and 120 minutes reperfusion and ex vivo (25 minutes ischemia and 60 minutes reperfusion. Expression and δ-opioid receptor (δ-OR phospho-regulation of pro-survival (Akt/PKB, Erk1/2, eNOS and pro-injury (GSK3β enzymes were also examined. OB rats were heavier (764±25 versus 657±22 g for CD; P<0.05, hyperleptinaemic (11.1±0.7 versus 5.0±0.7 for CD; P<0.01 and comparably insulin-insensitive (HOMA-IR of 63.2±3.3 versus 63.2±1.6 for CD. In vivo infarction was more than halved in OB (20±3% versus CD rats (45±6% P<0.05, as was post-ischaemic lactate dehydrogenase efflux (0.4±0.3 mU/ml versus 5.6±0.5 mU/ml; P<0.02 and ex vivo contractile dysfunction (62±2% versus 44±6% recovery of ventricular force; P<0.05. OB hearts exhibited up to 60% higher Akt expression, with increased phosphorylation of eNOS (+100%, GSK3β (+45% and Erk1/2 (+15%. Pre-ischaemic δ-OR agonism with BW373U86 improved recoveries in CD hearts in association with phosphorylation of Akt (+40%, eNOS (+75% and GSK3β (+30%, yet failed to further enhance RISK-NOS activation or I-R outcomes in OB hearts. In summary, dietary obesity in the context of age-related insulin-insensitivity paradoxically improves myocardial I-R tolerance, in association with moderate hyperleptinaemic and

Potassium and calcium channel gene expression in small arteries in porcine and rat models of diet-induced obesity (Poster)

DEFF Research Database (Denmark)

Jensen, Lars Jørn; Salomonsson, Max; Sørensen, Charlotte Mehlin

2014-01-01

Obesity is an increasing problem worldwide leading to cardiovascular morbidity. Only limited information exists on the transcriptional regulation of arterial K+ and Ca2+ channels in obesity. We quantified, by real-time PCR, mRNA expression of K+ channels and L-type Ca2+ channels (LTCC) in small...... mesenteric (MA), middle cerebral (MCA), and left coronary arteries (LCA) of lean vs. obese rats and minipigs. Male Sprague Dawley rats were fed a high-fat (FAT; N=5), high-fructose (FRUC; N=7), high-fat/high-fructose (FAT/FRUC; N=7) or standard diet (STD; N=7-11) for 28 Weeks. FAT and FAT/FRUC became obese...... increased in OB and OB+DIAB. BKca, IKca, SKca and/or LTCC mRNA was up-regulated in LCA from OB and OB+DIAB (n.s.). Expression of BKca mRNA was increased, whereas IKca mRNA decreased in MCA from OB (n.s.). SKca mRNA was decreased in MA from OB (n.s.). Diet-induced obesity in rats and minipigs lead to complex...

Maternal obesity and post-natal high fat diet disrupt hepatic circadian rhythm in rat offspring

Science.gov (United States)

Offspring of obese (Ob) rat dams gain greater body wt and fat mass when fed high-fat diet (HFD) as compared to controls. Alterations of diurnal circadian rhythm are known to detrimentally impact metabolically active tissues such as liver. We sought to determine if maternal obesity (MOb) leads to p...

Effect of Herbal Acupuncture with Sang-hwang(Phellinus linteus on High Fat Diet-induced Obesity in Rats

Directory of Open Access Journals (Sweden)

Ji Hyun Kim

2004-02-01

Full Text Available Acupuncture has fairly good weight-reducing effect in treating simple obesity due to the neuroendocrine regulation. In this study, the anti-obesity effects of herbal acupuncture (HA with Sang-hwang (Phellinus linteus at Fuai (SP16 were investigated in the rat fed on high-fat (HF diet. Sang-hwang mushroom has been proven to have anti-carcinogenic effects and Sang-hwang extracts are highly effective in treatment and preventive treatment of AIDS, diabetes and high blood-pressure. To determine whether the Sang-hwang herbal acupuncture may have the anti-obesity effect, male Sprague-Dawley (4-wk-old rats were fed a HF diet for 5 wk, which produced significant weight gain compared to rats were fed a normal diet, and then herbal acupuncture were treated for 3 wk in HF diet group. The body weight, food consumption, food effeciency ratio (FER, body fat mass, plasma nitric oxide (NO were investigated in rats fed on normal diet, HF diet, and HF diet with HA (HF-diet-HA groups. NO has been proposed to be involved in the regulation of food intake. In addition, the expression of appetite peptides such as orexigenic peptide neuropeptide Y (NPY and the anorectic peptide cholecystokinin (CCK were observed in the hypothalamus. HF-HA group reduced body weight gain, FER, body fat contents and NO concentration compared to HF diet group. The expression of NPY was reduced in arcuate nucleus (ARC, and CCK was increased in the paraventricular nucleus (PVN after treatment of HA. In conclusion, Sang-hwang HA reduced adipocity, plasma NO and hypothalamic NPY, but increased CCK expression in the HF diet-induced obesity rat, therefore HA may have anti-obesity action through regulating body weight and appetite peptide of the central nervous system.

Excessive endoplasmic reticulum stress and decreased neuroplasticity-associated proteins in prefrontal cortex of obese rats and the regulatory effects of aerobic exercise.

Science.gov (United States)

Li, Feng; Liu, Bei Bei; Cai, Ming; Li, Jing Jing; Lou, Shu-Jie

2018-04-06

Studies have shown high fat diet induced obesity may cause cognition impairment and down-regulation of neuroplasticity-associated proteins, while aerobic exercise could improve that damage. Endoplasmic reticulum stress (ERS) has been reported to play a key role in regulating neuroplasticity-associated proteins expression, folding and post-translational modification in hippocampus of obese rodent models, however, the effects of ERS on neuroplasticity-associated proteins and possible underlying mechanisms in prefrontal cortex are not fully clear. In order to clarify changes of neuroplasticity-associated proteins and ERS in the prefrontal cortex of obese rats, male SD rats were fed on high fat diet for 8 weeks to establish the obese model. Then, 8 weeks of aerobic exercise treadmill intervention was arranged for the obese rats. Results showed that high fat diet induced obesity caused hyperlipidemia, and significantly promoted FATP1 expression in the prefrontal cortex, meanwhile, we found up-regulation of GRP78, p-PERK, p-eIF2α, caspase-12, CHOP, and Bax/Bcl-2, reflecting the activation of ERS and ERS-mediated apoptosis. Moreover, reduced BDNF and SYN was found in obese rats. However, FATP1, GRP78, p-PERK, p-eIF2α, caspase-12, CHOP, and Bax/Bcl-2 expressions were obviously reversed by aerobic exercise intervention. These results suggested that dietary obesity could induce Prefrontal ERS in SD rats and excessive ERS may play a critical role in decreasing the levels of neuroplasticity-associated proteins. Moreover, aerobic exercise could relieve ERS, thus promoted the expression of neuroplasticity-associated proteins. Copyright © 2018. Published by Elsevier Inc.

Protective Effects of Tamarillo (Cyphomandra betacea Extract against High Fat Diet Induced Obesity in Sprague-Dawley Rats

Directory of Open Access Journals (Sweden)

Noor Atiqah Aizan Abdul Kadir

2015-01-01

Full Text Available This study aims to investigate the protective effect of Cyphomandra betacea in adult male Sprague-Dawley rats fed with high fat diet. Rats were fed on either normal chow or high fat diet for 10 weeks for obesity induction phase and subsequently received C. betacea extract at low dose (150 mg kg−1, medium dose (200 mg kg−1, or high dose (300 mg kg−1 or placebo via oral gavages for another 7 weeks for treatment phase. Treatment of obese rats with C. betacea extracts led to a significant decrease in total cholesterol and significant increase in HDL-C (p<0.05. Also there was a trend of positive reduction in blood glucose, triglyceride, and LDL-C with positive reduction of body weight detected in medium and high dosage of C. betacea extract. Interestingly, C. betacea treated rats showed positive improvement of superoxide dismutase (SOD activity and glutathione peroxidase (GPx activity along with a significant increase of total antioxidant status (TAS (p<0.05. Further, rats treated with C. betacea show significantly lower in TNF-α and IL-6 activities (p<0.05. This study demonstrates the potential use of Cyphomandra betacea extract for weight maintenance and complimentary therapy to suppress some obesity complication signs.

Grape Polyphenols Increase the Activity of HDL Enzymes in Old and Obese Rats

Directory of Open Access Journals (Sweden)

Andriy L. Zagayko

2013-01-01

Full Text Available HDL particles are protein-rich particles that act as a vehicle for reverse cholesterol transport from tissues to the liver. The purpose of this study was to investigate age-dependent changes in the functional activity of HDL and the effect of high-energy diet on this index, as well as to correct it under the influence of grape polyphenols from “Enoant” obtained from Vitis vinifera grapes. We observed the age-dependent composition changes in HDL particle. It was shown that total lipids and triacylglycerol (TG levels were higher in 24-month-old animals. In obese rats, HDL total lipids and TG levels were higher in 24-month-old than in the 3-month-old and 12-month-old groups but did not differ from 24-month-old group. The plasma HDL paraoxonase (PON and lecithin:cholesterol acyltransferase (LCAT activity levels were decreased in old-aged rats, and cholesteryl ester transfer protein (CETP activity was higher in old rats. Keeping 12-month-old animals on high-fructose diet completely leveled the age differences in the data that have been measured between 12-month-old and 24-month-old rats. After “Enoant” administration, an increase of HDL PON and LCAT activity levels and a reduction of CETP activity were found in 24-month-old and obese rats.

Maternal obesity during gestation impairs fatty acid oxidation and mitochondrial SIRT3 expression in rat offspring at weaning

Science.gov (United States)

In utero exposure to maternal obesity increases the offspring’s risk of obesity in later life. We have also previously reported that offspring of obese rat dams develop hepatic steatosis, mild hyperinsulinemia, and a lipogenic gene signature in the liver at postnatal day (PND) 21. In the current s...

Metabolic Disorders and Diabetic Complications in Spontaneously Diabetic Torii Leprfa Rat: A New Obese Type 2 Diabetic Model

Directory of Open Access Journals (Sweden)

Yusuke Kemmochi

2013-01-01

Full Text Available Spontaneously Diabetic Torii Leprfa (SDT fatty rat, established by introducing the fa allele of the Zucker fatty rat into SDT rat genome, is a new model of obese type 2 diabetes. Both male and female SDT fatty rats show overt obesity, and hyperglycemia and hyperlipidemia are observed at a young age as compared with SDT rats. With early incidence of diabetes mellitus, diabetic complications, such as nephropathy, retinopathy, and neuropathy, in SDT fatty rats were seen at younger ages compared to those in the SDT rats. In this paper, we overview pathophysiological features in SDT fatty rats and also describe new insights regarding the hematology, blood pressure, renal complications, and sexual dysfunction. The SDT fatty rats showed an increase of leukocytes, especially the monocyte count, prominent hypertension associated with salt drinking, end-stage renal disease with aging, and hypogonadism. Unlike other diabetic models, the characteristic of SDT fatty rat is to present an incidence of diabetes in females, hypertension, and retinopathy. SDT fatty rat is a useful model for analysis of various metabolic disorders and the evaluation of drugs related to metabolic disease.

ZINC-INDUCED HYPERLEPTINEMIA IN RATS RELATED TO THE AMELIORATION OF SUCROSE-INDUCED OBESITY WITH ZINC REPLETION

International Nuclear Information System (INIS)

HEIBASHY, M.I.; EL-NAHLA, A.M.; ASHOUR, I.; SALEH, SH.Y.A.

2008-01-01

Thirty adult albino rats (Rattus rattus) at 6 weeks of age were divided into three groups (ten for each). The first group was fed a standard laboratory diet for 8 weeks (control). The second group was made obese by giving them 32% sucrose solution in addition to the standard laboratory diet .The third group was received zinc supplementation (50 mg zinc acetate/ litre) with their sucrose solution. Body weight of all rats was measured weekly for 8 weeks. At 14 weeks of age, rats were killed and fasting blood samples were obtained. Serum glucose, insulin, cholesterol, triglyceride, leptin, tumour necrosis factor-α and zinc were measured.Results showed remarkable changes in body weights in sucrose fed rats only when compared to control and supplemented zinc rats group. Serum glucose, insulin, cholesterol and triglycerides were significantly increased in sucrose fed rats than both control and sucrose with zinc group. Serum leptin showed significant increase in sucrose fed rats than control and also showed higher significant value in sucrose fed rats supplemented with zinc comparing with sucrose fed rats and control ones. Tumour necrosis factor-? did not show any significant difference between all groups. Serum zinc concentration was decreased significantly in sucrose fed rats as compared to control. On the other hand, it was increased significantly in sucrose fed rats supplemented with zinc than other both groups. It could be concluded that zinc supplementation induced hyperleptinemia caused ameliorating effects in obese rats

High-fat-diet-induced obesity causes an inflammatory and tumor-promoting microenvironment in the rat kidney

Directory of Open Access Journals (Sweden)

Kerstin Stemmer

2012-09-01

Obesity and concomitant comorbidities have emerged as public health problems of the first order. For instance, obese individuals have an increased risk for kidney cancer. However, direct mechanisms linking obesity with kidney cancer remain elusive. We hypothesized that diet-induced obesity (DIO promotes renal carcinogenesis by inducing an inflammatory and tumor-promoting microenvironment. We compared chow-fed lean Wistar rats with those that were sensitive (DIOsens or partially resistant (DIOres to DIO to investigate the impact of body adiposity versus dietary nutrient overload in the development of renal preneoplasia and activation of tumor-promoting signaling pathways. Our data clearly show a correlation between body adiposity, the severity of nephropathy, and the total number and incidence of preneoplastic renal lesions. However, similar plasma triglyceride, plasma free fatty acid and renal triglyceride levels were found in chow-fed, DIOres and DIOsens rats, suggesting that lipotoxicity is not a critical contributor to the renal pathology. Obesity-related nephropathy was further associated with regenerative cell proliferation, monocyte infiltration and higher renal expression of monocyte chemotactic protein-1 (MCP-1, interleukin (IL-6, IL-6 receptor and leptin receptor. Accordingly, we observed increased signal transducer and activator of transcription 3 (STAT3 and mammalian target of rapamycin (mTOR phosphorylation in tubules with preneoplastic phenotypes. In summary, our results demonstrate that high body adiposity induces an inflammatory and proliferative microenvironment in rat kidneys that promotes the development of preneoplastic lesions, potentially via activation of the STAT3 and mTOR signaling pathways.

Overfeeding-Induced Obesity in Rats : Insulin Sensitivity and Autonomic Regulation of Metabolism

NARCIS (Netherlands)

Balkan, B; Strubbe, J.H.; Bruggink, J.E.; Steffens, A.B.

1993-01-01

The metabolic consequences of the development of obesity and the underlying mechanisms were investigated. For this purpose, male rats were overfed for 5 weeks through long-term gastric catheters. Permanent cardiac cannulas implanted before the overfeeding period allowed frequent blood sampling and

Vitamin A as a key regulator of obesity & its associated disorders: Evidences from an obese rat model

Directory of Open Access Journals (Sweden)

Shanmugam M Jeyakumar

2015-01-01

Full Text Available During the last century, vitamin A has evolved from its classical role as a fat-soluble vitamin and attained the status of para-/autocrine hormone. Besides its well-established role in embryogenesis, growth and development, reproduction and vision, vitamin A has also been implicated in several other physiological processes. Emerging experimental evidences emphasize adipose tissue as an active endocrine organ with great propensity to continuous growth (throughout life. Due to various genetic and lifestyle factors, excess energy accumulates in adipose tissue as fat, resulting in obesity and other complications such as type 2 diabetes, hypertension, and cardiovascular disease. Recent in vitro and in vivo studies have shed light on vitamin A metabolites; retinaldehyde and retinoic acid and participation of their pathway proteins in the regulation of adipose tissue metabolism and thus, obesity. In this context, we discuss here some of our important findings, which establish the role of vitamin A (supplementation in obesity and its associated disorders by employing an obese rat model; WNIN/Ob strain.

Opuntia ficus indica (nopal) attenuates hepatic steatosis and oxidative stress in obese Zucker (fa/fa) rats.

Science.gov (United States)

Morán-Ramos, Sofía; Avila-Nava, Azalia; Tovar, Armando R; Pedraza-Chaverri, José; López-Romero, Patricia; Torres, Nimbe

2012-11-01

Nonalcoholic fatty liver disease (NAFLD) is associated with multiple factors such as obesity, insulin resistance, and oxidative stress. Nopal, a cactus plant widely consumed in the Mexican diet, is considered a functional food because of its antioxidant activity and ability to improve biomarkers of metabolic syndrome. The aim of this study was to assess the effect of nopal consumption on the development of hepatic steatosis and hepatic oxidative stress and on the regulation of genes involved in hepatic lipid metabolism. Obese Zucker (fa/fa) rats were fed a control diet or a diet containing 4% nopal for 7 wk. Rats fed the nopal-containing diet had ∼50% lower hepatic TG than the control group as well as a reduction in hepatomegaly and biomarkers of hepatocyte injury such as alanine and aspartate aminotransferases. Attenuation of hepatic steatosis by nopal consumption was accompanied by a higher serum concentration of adiponectin and a greater abundance of mRNA for genes involved in lipid oxidation and lipid export and production of carnitine palmitoyltransferase-1 and microsomal TG transfer proteins in liver. Hepatic reactive oxygen species and lipid peroxidation biomarkers were significantly lower in rats fed nopal compared with the control rats. Furthermore, rats fed the nopal diet had a lower postprandial serum insulin concentration and a greater liver phosphorylated protein kinase B (pAKT):AKT ratio in the postprandial state. This study suggests that nopal consumption attenuates hepatic steatosis by increasing fatty acid oxidation and VLDL synthesis, decreasing oxidative stress, and improving liver insulin signaling in obese Zucker (fa/fa) rats.

Acute insulin-induced elevations of circulating leptin and feeding inhibition in lean but not obese rats.

Science.gov (United States)

Singh, Kimberly A; Boozer, Carol N; Vasselli, Joseph R

2005-08-01

Insulin has been shown to stimulate leptin mRNA expression acutely in rat adipose tissue, but its short-term effects on circulating leptin levels, and subsequent feeding behavior, have not been well described. We used 11-mo-old female selectively bred obesity-resistant (OR) and obesity-prone (OP) Sprague-Dawley rats maintained on laboratory chow to investigate this question. At testing, body weights and basal leptin levels of the OP rats were significantly elevated compared with the OR rats. In the 3-h fasted state, injection of 2.0 U insulin/kg ip resulted in significant elevations of plasma leptin at 4 h postinjection in both OP and OR groups (hour 4, +2.50 and +5.98 ng/ml, respectively). In separate feeding tests with the same groups, intake of laboratory chow pellets was significantly inhibited during hours 2-4 after 2.0 U/kg of insulin in the OR (-80.1%, P < 0.05), but not in the OP group, compared with intake after saline injections. In feeding tests with palatable moderately high-fat pellets after 2.0 and 3.0 U insulin/kg ip, significant decreases between hours 2 and 4 in intake were seen in the OR group only (-41.0 and -68.3%, respectively). Thus feeding inhibition coincides with insulin-induced elevations of plasma leptin in lean but not obese Sprague-Dawley rats. Our data suggest that elevations of leptin within the physiological range may contribute to short-term inhibition of food intake in rats and that this process may be stimulated by feeding-related insulin release.

EFFECTS OF PHYSICAL EXERCISES ON TRIACYLGLYCEROL LEVEL IN SKELETAL MUSCLES IN DIETARY-INDUCED OBESE RATS

Directory of Open Access Journals (Sweden)

I. Yu. Yakimovich

2014-01-01

Full Text Available The accumulation of triacylglycerol in peripheral tissues is one of mechanisms of insulin resistance. This paper presents the investigation of the influence of aerobic and anaerobic physical exercises on triacylglycerol level in skeletal muscles and on insulin resistance in dietary-induced obese rats. It is estimated that a high-energy (HE diet causes the accumulation of triacylglycerols in skeletal muscles that leads to high resistance to insulin. Aerobic and anaerobic physical exercises reduce the level of triacylglycerols in skeletal  muscles  and  raise  sensitivity to  insulin  in  obese  rats.  Physical  exercises  raise  the  level  of triacylglycerols in skeletal muscles in standard-diet rats that probably is the adaptation to high energy expenditure, but does not lead to high insulin resistance.

Changes in gut microbiota in rats fed a high fat diet correlate with obesity-associated metabolic parameters.

Science.gov (United States)

Lecomte, Virginie; Kaakoush, Nadeem O; Maloney, Christopher A; Raipuria, Mukesh; Huinao, Karina D; Mitchell, Hazel M; Morris, Margaret J

2015-01-01

The gut microbiota is emerging as a new factor in the development of obesity. Many studies have described changes in microbiota composition in response to obesity and high fat diet (HFD) at the phylum level. In this study we used 16s RNA high throughput sequencing on faecal samples from rats chronically fed HFD or control chow (n = 10 per group, 16 weeks) to investigate changes in gut microbiota composition at the species level. 53.17% dissimilarity between groups was observed at the species level. Lactobacillus intestinalis dominated the microbiota in rats under the chow diet. However this species was considerably less abundant in rats fed HFD (Pdevelopment of the obese phenotype, we correlated their abundance with metabolic parameters associated with obesity. Of the taxa contributing the most to dissimilarity between groups, 10 presented significant correlations with at least one of the tested parameters, three of them correlated positively with all metabolic parameters: Phascolarctobacterium, Proteus mirabilis and Veillonellaceae, all propionate/acetate producers. Lactobacillus intestinalis was the only species whose abundance was negatively correlated with change in body weight and fat mass. This species decreased drastically in response to HFD, favouring propionate/acetate producing bacterial species whose abundance was strongly correlated with adiposity and deterioration of metabolic factors. Our observations suggest that these species may play a key role in the development of obesity in response to a HFD.

Blockade of RAGE in Zucker obese rats with experimental periodontitis

DEFF Research Database (Denmark)

Grauballe, M B; Østergaard, J A; Schou, S

2017-01-01

BACKGROUND AND OBJECTIVE: Periodontitis and type 2 diabetes mellitus (T2D) are two interrelated chronic diseases. Periodontitis is more prevalent in patients with T2D than in healthy subjects, and studies indicate that periodontitis impacts the metabolic control of patients with T2D. Hyperglycemia...... on the interrelationship between periodontitis and T2D in a rat model of both diseases. MATERIAL AND METHODS: Zucker obese rats (HsdHlr:ZUCKER-Lepr (fa/fa) ) and their lean littermates were divided into five treatment groups, with and without periodontitis. Monoclonal anti-RAGE IgG3 were injected into the rats three times...... evaluated in plasma. Kidney complications were evaluated by quantitative real-time PCR, the creatinine clearance rate, the albumin excretion rate and kidney hypertrophy. Periodontitis was evaluated by morphometric registration of alveolar bone loss and radiographic recording of bone support. RESULTS...

Vitamin A decreases pre-receptor amplification of glucocorticoids in obesity: study on the effect of vitamin A on 11beta-hydroxysteroid dehydrogenase type 1 activity in liver and visceral fat of WNIN/Ob obese rats

Directory of Open Access Journals (Sweden)

Ayyalasomayajula Vajreswari

2011-06-01

Full Text Available Abstract Background 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1 catalyzes the conversion of inactive glucocorticoids to active glucocorticoids and its inhibition ameliorates obesity and metabolic syndrome. So far, no studies have reported the effect of dietary vitamin A on 11β-HSD1 activity in visceral fat and liver under normal and obese conditions. Here, we studied the effect of chronic feeding of vitamin A-enriched diet (129 mg/kg diet on 11β-HSD1 activity in liver and visceral fat of WNIN/Ob lean and obese rats. Methods Male, 5-month-old, lean and obese rats of WNIN/Ob strain (n = 16 for each phenotype were divided into two subgroups consisting of 8 rats of each phenotype. Control groups received stock diet containing 2.6 mg vitamin A/kg diet, where as experimental groups received diet containing 129 mg vitamin A/Kg diet for 20 weeks. Food and water were provided ad libitum. At the end of the experiment, tissues were collected and 11β-HSD1 activity was assayed in liver and visceral fat. Results Vitamin A supplementation significantly decreased body weight, visceral fat mass and 11β-HSD1 activity in visceral fat of WNIN/Ob obese rats. Hepatic 11β-HSD1 activity and gene expression were significantly reduced by vitamin A supplementation in both the phenotypes. CCAAT/enhancer binding protein α (C/EBPα, the main transcription factor essential for the expression of 11β-HSD1, decreased in liver of vitamin A fed-obese rats, but not in lean rats. Liver × receptor α (LXRα, a nuclear transcription factor which is known to downregulate 11β-HSD1 gene expression was significantly increased by vitamin A supplementation in both the phenotypes. Conclusions This study suggests that chronic consumption of vitamin A-enriched diet decreases 11β-HSD1 activity in liver and visceral fat of WNIN/Ob obese rats. Decreased 11β-HSD1 activity by vitamin A may result in decreased levels of active glucocorticoids in adipose tissue and possibly

Red wine polyphenols prevent metabolic and cardiovascular alterations associated with obesity in Zucker fatty rats (Fa/Fa.

Directory of Open Access Journals (Sweden)

Abdelali Agouni

Full Text Available BACKGROUND: Obesity is associated with increased risks for development of cardiovascular diseases. Epidemiological studies report an inverse association between dietary flavonoid consumption and mortality from cardiovascular diseases. We studied the potential beneficial effects of dietary supplementation of red wine polyphenol extract, Provinols, on obesity-associated alterations with respect to metabolic disturbances and cardiovascular functions in Zucker fatty (ZF rats. METHODOLOGY/PRINCIPAL FINDINGS: ZF rats or their lean littermates received normal diet or supplemented with Provinols for 8 weeks. Provinols improved glucose metabolism by reducing plasma glucose and fructosamine in ZF rats. Moreover, it reduced circulating triglycerides and total cholesterol as well as LDL-cholesterol in ZF rats. Echocardiography measurements demonstrated that Provinols improved cardiac performance as evidenced by an increase in left ventricular fractional shortening and cardiac output associated with decreased peripheral arterial resistances in ZF rats. Regarding vascular function, Provinols corrected endothelial dysfunction in aortas from ZF rats by improving endothelium-dependent relaxation in response to acetylcholine (Ach. Provinols enhanced NO bioavailability resulting from increased nitric oxide (NO production through enhanced endothelial NO-synthase (eNOS activity and reduced superoxide anion release via decreased expression of NADPH oxidase membrane sub-unit, Nox-1. In small mesenteric arteries, although Provinols did not affect the endothelium-dependent response to Ach; it enhanced the endothelial-derived hyperpolarizing factor component of the response. CONCLUSIONS/SIGNIFICANCE: Use of red wine polyphenols may be a potential mechanism for prevention of cardiovascular and metabolic alterations associated with obesity.

Physical exercise restores microvascular function in obese rats with metabolic syndrome.

Science.gov (United States)

Machado, Marcus Vinicius; Vieira, Aline Bomfim; Nascimento, Alessandro Rodrigues; Martins, Rômulo Lanza; Daleprane, Julio Beltrame; Lessa, Marcos Adriano; Tibiriçá, Eduardo

2014-11-01

Obesity and metabolic syndrome are related to systemic functional microvascular alterations, including a significant reduction in microvessel density. The aim of this study was to investigate the effects of exercise training on functional capillary density in the skeletal muscle and skin of obese rats with metabolic syndrome. We used male Wistar-Kyoto rats that had been fed a standard commercial diet (CON) or high-fat diet (HFD) for 32 weeks. Animals receiving the HFD were randomly divided into sedentary (HFD+SED) and training groups (HFD+TR) at the 20(th) week. After 12 weeks of aerobic treadmill training, the maximal oxygen uptake (VO2max); hemodynamic, biochemical, and anthropometric parameters; and functional capillary density were assessed. In addition, a maximal exercise test was performed. Exercise training increased the VO2max (69 ± 3 mL/kg per min) and exercise tolerance (30 ± 1 min) compared with the HFD+SED (41 ± 6 mL/kg per min, P Exercise training also increased the number of spontaneously perfused capillaries in the skeletal muscle (252 ± 9 vs. 207 ± 9 capillaries/mm(2)) of the training group compared with that in the sedentary animals (260 ± 15 capillaries/mm(2)). These results demonstrate that exercise training reverses capillary rarefaction in our experimental model of metabolic syndrome and obesity.

Effects and mechanisms of caffeine to improve immunological and metabolic abnormalities in diet-induced obese rats.

Science.gov (United States)

Liu, Chih-Wei; Tsai, Hung-Cheng; Huang, Chia-Chang; Tsai, Chang-Youh; Su, Yen-Bo; Lin, Ming-Wei; Lee, Kuei-Chuan; Hsieh, Yun-Cheng; Li, Tzu-Hao; Huang, Shiang-Fen; Yang, Ying-Ying; Hou, Ming-Chih; Lin, Han-Chieh; Lee, Fa-Yauh; Lee, Shou-Dong

2018-05-01

In obesity, there are no effective therapies for parallel immune and metabolic abnormalities, including systemic/tissue insulin-resistance/inflammation, adiposity and hepatic steatosis. Caffeine has anti-inflammation, antihepatic steatosis, and anti-insulin resistance effects. In this study, we evaluated the effects and molecular mechanisms of 6 wk of caffeine treatment (HFD-caf) on immunological and metabolic abnormalities of high-fat diet (HFD)-induced obese rats. Compared with HFD vehicle (HFD-V) rats, in HFD-caf rats the suppressed circulating immune cell inflammatory [TNFα, MCP-1, IL-6, intercellular adhesion molecule 1 (ICAM-1), and nitrite] profiles were accompanied by decreased liver, white adipose tissue (WAT), and muscle macrophages and their intracellular cytokine levels. Metabolically, the increase in metabolic rates reduced lipid accumulation in various tissues, resulting in reduced adiposity, lower fat mass, decreased body weight, amelioration of hepatic steatosis, and improved systemic/muscle insulin resistance. Further mechanistic approaches revealed an upregulation of tissue lipogenic [(SREBP1c, fatty acid synthase, acetyl-CoA carboxylase)/insulin-sensitizing (GLUT4 and p-IRS1)] markers in HFD-caf rats. Significantly, ex vivo experiments revealed that the cytokine release by the cocultured peripheral blood mononuclear cell (monocyte) and WAT (adipocyte), which are known to stimulate macrophage migration and hepatocyte lipogenesis, were lower in HFD-V groups than HFD-caf groups. Caffeine treatment simultaneously ameliorates immune and metabolic pathogenic signals present in tissue to normalize immunolgical and metabolic abnormalities found in HFD-induced obese rats.

Effects of exercise and diet change on cognition function and synaptic plasticity in high fat diet induced obese rats

Science.gov (United States)

2013-01-01

Background Nutritional imbalance-induced obesity causes a variety of diseases and in particular is an important cause of cognitive function decline. This study was performed on Sprague Dawley (SD) rats with 13-weeks of high fat diet-induced obesity in connection to the effects of regular exercise and dietary control for 8 weeks on the synaptic plasticity and cognitive abilities of brain. Methods Four weeks-old SD rats were adopted classified into normal-normal diet-sedentary (NNS, n = 8), obesity-high fat diet-sedentary (OHS, n = 8), obesity-high fat diet-training (OHT, n = 8), obesity-normal diet-sedentary (ONS, n = 8) and obesity- normal diet-training (ONT, n = 8). The exercise program consisted of a treadmill exercise administered at a speed of 8 m/min for 1–4 weeks, and 14 m/min for 5–8 weeks. The Western blot method was used to measure the expression of NGF, BDNF, p38MAPK and p-p38MAPK proteins in hippocampus of the brain, and expressions of NGF, BDNF, TrkA, TrkB, CREB and synapsin1 mRNA were analyzed through qRT-PCR. Results The results suggest cognitive function-related protein levels and mRNA expression to be significantly decreased in the hippocampus of obese rats, and synaptic plasticity as well as cognitive function signaling sub-pathway factors were also significantly decreased. In addition, 8-weeks exercises and treatment by dietary change had induced significant increase of cognitive function-related protein levels and mRNA expression as well as synaptic plasticity and cognitive function signaling sub-pathway factors in obese rats. In particular, the combined treatment had presented even more positive effect. Conclusions Therefore, it was determined that the high fat diet-induced obesity decreases plasticity and cognitive function of the brain, but was identified as being improved by exercises and dietary changes. In particular, it is considered that regular exercise has positive effects on memory span and learning

Angiotensin II Type 2 Receptor and Receptor Mas Are Colocalized and Functionally Interdependent in Obese Zucker Rat Kidney

DEFF Research Database (Denmark)

Patel, Sanket N; Ali, Quaisar; Samuel, Preethi

2017-01-01

The actions of angiotensin II type 2 receptor (AT2R) and the receptor Mas (MasR) are complex but show similar pronatriuretic function; particularly, AT2R expression and natriuretic function are enhanced in obese/diabetic rat kidney. In light of some reports suggesting a potential positive...... interaction between these receptors, we tested hypothesis that renal AT2R and MasR physically interact and are interdependent to stimulate cell signaling and promote natriuresis in obese rats. We found that infusion of AT2R agonist C21 in obese Zucker rats (OZR) increased urine flow and urinary Na excretion...... coimmunoprecipitated with MasR in cortical homogenate of OZR. Immunoblotting of cortical homogenate cross-linked with zero-length oxidative (sulfhydryl groups) cross-linker cupric-phenanthroline revealed a shift of AT2R and MasR bands upward with overlapping migration for their complexes which were sensitive...

Exercise training and return to a well-balanced diet activate the neuregulin 1/ErbB pathway in skeletal muscle of obese rats.

Science.gov (United States)

Ennequin, Gaël; Boisseau, Nathalie; Caillaud, Kevin; Chavanelle, Vivien; Gerbaix, Maude; Metz, Lore; Etienne, Monique; Walrand, Stéphane; Masgrau, Aurélie; Guillet, Christelle; Courteix, Daniel; Niu, Airu; Li, Yi-Ping; Capel, Fréderic; Sirvent, Pascal

2015-06-15

Some studies suggest that neuregulin 1 (NRG1) could be involved in the regulation of skeletal muscle energy metabolism in rodents. Here we assessed whether unbalanced diet is associated with alterations of the NRG1 signalling pathway and whether exercise and diet might restore NRG1 signalling in skeletal muscle of obese rats. We show that diet-induced obesity does not impair NRG1 signalling in rat skeletal muscle. We also report that endurance training and a well-balanced diet activate the NRG1 signalling in skeletal muscle of obese rats, possibly via a new mechanism mediated by the protease ADAM17. These results suggest that some beneficial effects of physical activity and diet in obese rats could be partly explained by stimulation of the NRG1 signalling pathway. Some studies suggest that the signalling pathway of neuregulin 1 (NRG1), a protein involved in the regulation of skeletal muscle metabolism, could be altered by nutritional and exercise interventions. We hypothesized that diet-induced obesity could lead to alterations of the NRG1 signalling pathway and that chronic exercise could improve NRG1 signalling in rat skeletal muscle. To test this hypothesis, male Wistar rats received a high fat/high sucrose (HF/HS) diet for 16 weeks. At the end of this period, NRG1 and ErbB expression/activity in skeletal muscle was assessed. The obese rats then continued the HF/HS diet or were switched to a well-balanced diet. Moreover, in both groups, half of the animals also performed low intensity treadmill exercise training. After another 8 weeks, NRG1 and ErbB expression/activity in skeletal muscle were tested again. The 16 week HF/HS diet induced obesity, but did not significantly affect the NRG1/ErbB signalling pathway in rat skeletal muscle. Conversely, after the switch to a well-balanced diet, NRG1 cleavage ratio and ErbB4 amount were increased. Chronic exercise training also promoted NRG1 cleavage, resulting in increased ErbB4 phosphorylation. This result was

Growth hormone and IGF-1 deficiency exacerbate high-fat diet-induced endothelial impairment in obese Lewis dwarf rats: implications for vascular aging.

Science.gov (United States)

Bailey-Downs, Lora C; Sosnowska, Danuta; Toth, Peter; Mitschelen, Matthew; Gautam, Tripti; Henthorn, Jim C; Ballabh, Praveen; Koller, Akos; Farley, Julie A; Sonntag, William E; Csiszar, Anna; Ungvari, Zoltan

2012-06-01

Previous studies suggest that the age-related decline in circulating growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels significantly contribute to vascular dysfunction in aging by impairing cellular oxidative stress resistance pathways. Obesity in elderly individuals is increasing at alarming rates, and there is evidence suggesting that elderly individuals are more vulnerable to the deleterious cardiovascular effects of obesity than younger individuals. However, the specific mechanisms through which aging, GH/IGF-1 deficiency, and obesity interact to promote the development of cardiovascular disease remain unclear. To test the hypothesis that low circulating GH/IGF-1 levels exacerbate the pro-oxidant and proinflammatory vascular effects of obesity, GH/IGF-1-deficient Lewis dwarf rats and heterozygous control rats were fed either a standard diet or a high-fat diet (HFD) for 7 months. Feeding an HFD resulted in similar relative weight gains and increases in body fat content in Lewis dwarf rats and control rats. HFD-fed Lewis dwarf rats exhibited a relative increase in blood glucose levels, lower insulin, and impaired glucose tolerance as compared with HFD-fed control rats. Analysis of serum cytokine expression signatures indicated that chronic GH/IGF-1 deficiency exacerbates HFD-induced inflammation. GH/IGF-1 deficiency also exacerbated HFD-induced endothelial dysfunction, oxidative stress, and expression of inflammatory markers (tumor necrosis factor-α, ICAM-1) in aortas of Lewis dwarf rats. Overall, our results are consistent with the available clinical and experimental evidence suggesting that GH/IGF-1 deficiency renders the cardiovascular system more vulnerable to the deleterious effects of obesity.

Antiobesity Effect of Codonopsis lanceolata in High-Calorie/High-Fat-Diet-Induced Obese Rats

Directory of Open Access Journals (Sweden)

Hye-Kyung Choi

2013-01-01

Full Text Available The antiobesity effects of Codonopsis lanceolata (CL were evaluated in a high-calorie/high-fat-diet (HFD- induced obesity rat model and 3T3-L1 cells. The Sprague-Dawley male rats were fed a normal diet (ND or a HFD for a period of 12 weeks. The rats were subdivided into groups: ND, ND + wild Codonopsis lanceolata (wCL (900 mg/kg/day, p.o., ND + cultivated Codonopsis lanceolata (cCL (900 mg/kg/day, p.o., HFD, HFD + wCL (100, 300, or 900 mg/kg/day, p.o., HFD + cCL (100, 300, or 900 mg/kg/day, p.o., and HFD + sibutramine. The body weight gains of the administered HFD + CL (wCL or CCL were lower than those of the rats fed with only the HFD group. Moreover, the weight of adipose pads and the serum levels of triglycerides, total cholesterol, and low density lipoprotein cholesterol in the group administered HDL + CL were significantly lower than in the HFD group. The inhibitory effect of lipid accumulation in 3T3-L1 cells was measured by Oil Red O staining and reverse transcription-polymerase chain reaction (RT-PCR. Treatment of 3T3-L1 cells with wCL inhibited lipid accumulation and expression of C/EBPα and PPARγ. These results suggest that CL has a great potential as a functional food with anti-obesity effects and as a therapeutic alternative in the treatment of obesity.

The effects of altitude training on the AMPK-related glucose transport pathway in the red skeletal muscle of both lean and obese Zucker rats.

Science.gov (United States)

Chen, Yu-Ching; Lee, Shin-Da; Kuo, Cha-Hua; Ho, Low-Tone

2011-01-01

The skeletal muscle AMP-activated protein kinase (AMPK)-related glucose transport pathway is involved in glucose homeostasis. In this study, we examined whether obese control Zucker rats had abnormal expression of proteins in the LKB1-AMPK-AS160-GLUT4 pathway in red gastrocnemius muscle compared to that in lean (normal) control Zucker rats. We also compared the chronic training effects of exercise, hypoxia, and altitude training on this pathway in lean and obese rats. At sea level, lean and obese rats were divided into 4 groups for 6 weeks training as follows: 1) control; 2) exercise (progressive daily swimming-exercise training with comparable exercise signals between the two groups); 3) hypoxia (8 hours of daily 14% O2 exposure); and 4) exercise plus hypoxia (also called altitude training). Seven animals were used for each group. The obese rats in the control group had higher body weights, elevated fasting insulin and glucose levels, and higher baseline levels of muscle AMPK and AS160 phosphorylation compared with those of lean control rats. For obese Zucker rats in the exercise or hypoxia groups, the muscle AMPK phosphorylation level was significantly decreased compared with that of the control group. For obese Zucker rats in the altitude training group, the levels of AMPK, AS160 phosphorylation, fasting insulin, and fasting glucose were decreased concomitant with an approximate 50% increase in the muscle GLUT4 protein level compared with those of the control group. In lean rats, the altitude training efficiently lowered fasting glucose and insulin levels and increased muscle AMPK and AS160 phosphorylation as well as GLUT4 protein levels. Our results provide evidence that long-term altitude training may be a potentially effective nonpharmacological strategy for treating and preventing insulin resistance based on its effects on the skeletal muscle AMPK-AS160-GLUT4 pathway.

Discordant Documentation of Obesity Body Mass Index and Obesity Diagnosis in Electronic Medical Records

Directory of Open Access Journals (Sweden)

Jennifer T. Fink

2014-11-01

Full Text Available Purpose: This study examined concordance between presence of obesity body mass index (BMI, defined as BMI ≥ 30, in the patient’s electronic medical record (EMR and a documented diagnosis of obesity. Methods: We conducted a retrospective review of the EMR in a large health care system for a 1-year period (2012. A total of 397,313 patients met the study criteria of having at least one physician visit, being at least 18 years of age, and not being pregnant. Of those, 158,327 (40% had a recorded BMI ≥ 30. We examined the EMR of these obese patients to determine whether a diagnosis of obesity was recorded, and whether demographics or comorbid diagnoses impacted the likelihood of a recorded obesity diagnosis. Results: Obesity appeared on the EMR problem list for only 35% of patients with BMI ≥ 30. Obesity diagnosis was documented more frequently in women, middle-aged patients and blacks. The presence of some comorbidities (e.g. sleep apnea, hypertension, diabetes led to significantly more frequent diagnosis of obesity. There was a significant positive association between the number of comorbid diagnoses per patient and an obesity diagnosis appearing on the problem list. Conclusions: Obesity remains underrecorded in the EMR problem list despite the presence of obesity BMI in the EMR. Patient demographics and comorbidities should be considered when identifying best practices for weight management. New practices should be patient-centered and consider cultural context as well as the social and physical resources available to patients – all crucial for enacting systems change in a true accountable care environment.

Effects of high-fat diet and fructose-rich diet on obesity, dyslipidemia and hyperglycemia in the WBN/Kob-Leprfa rat, a new model of type 2 diabetes mellitus.

Science.gov (United States)

Namekawa, Junichi; Takagi, Yoshiichi; Wakabayashi, Kaoru; Nakamura, Yuki; Watanabe, Ayaka; Nagakubo, Dai; Shirai, Mitsuyuki; Asai, Fumitoshi

2017-06-10

Obesity and type 2 diabetes mellitus (T2DM) are occurring at epidemic-like rates, and these epidemics appear to have emerged largely from changes in daily diet. In the present study, we compared effects of high-fat diet (HFD) and fructose-rich diet (FRD) in WBN/Kob-Lepr fa (WBKDF) rats that spontaneously develop obesity, dyslipidemia and T2DM. After a 4-week feeding of each diet, WBKDF-HFD and WBKDF-FRD rats exhibited aggravated obesity and dyslipidemia compared with WBKDF rats fed standard diet (STD). In contrast, hyperglycemia developed in WBKDF-STD rats was significantly inhibited in WBKDF-FRD rats, but not in WBKDF-HFD rats. The present study demonstrated that the 4-week feeding of HFD and FRD caused diet-induced obesity with a distinct phenotype in the glucose metabolism in WBKDF rats.

High fat diet-fed obese rats are highly sensitive to doxorubicin-induced cardiotoxicity

International Nuclear Information System (INIS)

Mitra, Mayurranjan S.; Donthamsetty, Shashikiran; White, Brent; Mehendale, Harihara M.

2008-01-01

Often, chemotherapy by doxorubicin (Adriamycin) is limited due to life threatening cardiotoxicity in patients during and posttherapy. Recently, we have shown that moderate diet restriction remarkably protects against doxorubicin-induced cardiotoxicity. This cardioprotection is accompanied by decreased cardiac oxidative stress and triglycerides and increased cardiac fatty-acid oxidation, ATP synthesis, and upregulated JAK/STAT3 pathway. In the current study, we investigated whether a physiological intervention by feeding 40% high fat diet (HFD), which induces obesity in male Sprague-Dawley rats (250-275 g), sensitizes to doxorubicin-induced cardiotoxicity. A LD 10 dose (8 mg doxorubicin/kg, ip) administered on day 43 of the HFD feeding regimen led to higher cardiotoxicity, cardiac dysfunction, lipid peroxidation, and 80% mortality in the obese (OB) rats in the absence of any significant renal or hepatic toxicity. Doxorubicin toxicokinetics studies revealed no change in accumulation of doxorubicin and doxorubicinol (toxic metabolite) in the normal diet-fed (ND) and OB hearts. Mechanistic studies revealed that OB rats are sensitized due to: (1) higher oxyradical stress leading to upregulation of uncoupling proteins 2 and 3, (2) downregulation of cardiac peroxisome proliferators activated receptor-α, (3) decreased plasma adiponectin levels, (4) decreased cardiac fatty-acid oxidation (666.9 ± 14.0 nmol/min/g heart in ND versus 400.2 ± 11.8 nmol/min/g heart in OB), (5) decreased mitochondrial AMP-α2 protein kinase, and (6) 86% drop in cardiac ATP levels accompanied by decreased ATP/ADP ratio after doxorubicin administration. Decreased cardiac erythropoietin and increased SOCS3 further downregulated the cardioprotective JAK/STAT3 pathway. In conclusion, HFD-induced obese rats are highly sensitized to doxorubicin-induced cardiotoxicity by substantially downregulating cardiac mitochondrial ATP generation, increasing oxidative stress and downregulating the JAK/STAT3

Metformin ameliorates diabetes but does not normalize the decreased GLUT 4 content in skeletal muscle of obese (fa/fa) Zucker rats

DEFF Research Database (Denmark)

Handberg, A; Kayser, L; Høyer, P E

1993-01-01

We studied the expression of the glucose transporter GLUT 4 in the soleus and red gastrocnemius muscles from obese, diabetic (fa/fa) Zucker rats compared to their lean littermates (Fa/-), with and without treatment with the antidiabetic drug metformin. In the untreated groups of rats, the GLUT 4...... content in a crude membrane fraction of both the soleus and the red gastrocnemius muscles were significantly lower in the obese (fa/fa) rats (3.46 +/- 0.28 vs. 6.04 +/- 0.41, p ... the same rats were confirmed by quantitative immunofluorescence microscopy, and the results were significantly correlated with the results obtained from quantitative immunoblotting (rho = 0.70, p fa/fa rats could contribute to the well-established insulin...

Early overfeed-induced obesity leads to brown adipose tissue hypoactivity in rats.

Science.gov (United States)

de Almeida, Douglas L; Fabrício, Gabriel S; Trombini, Amanda B; Pavanello, Audrei; Tófolo, Laize P; da Silva Ribeiro, Tatiane A; de Freitas Mathias, Paulo C; Palma-Rigo, Kesia

2013-01-01

Brown adipose tissue activation has been considered a potential anti-obesity mechanism because it is able to expend energy through thermogenesis. In contrast, white adipose tissue stores energy, contributing to obesity. We investigated whether the early programming of obesity by overfeeding during lactation changes structure of interscapular brown adipose tissue in adulthood and its effects on thermogenesis. Birth of litters was considered day 0. On day 2, litter size was adjusted to normal (9 pups) and small (3 pups) litters. On day 21, the litters were weaned. A temperature transponder was implanted underneath interscapular brown adipose tissue pads of 81-day-old animals; local temperature was measured during light and dark periods between days 87 and 90. The animals were euthanized, and tissue and blood samples were collected for further analysis. The vagus and retroperitoneal sympathetic nerve activity was recorded. Small litter rats presented significant lower interscapular brown adipose tissue temperature during the light (NL 37.6°C vs. SL 37.2°C) and dark (NL 38°C vs. SL 37.6°C) periods compared to controls. Morphology of small litter brown adipose tissue showed fewer lipid droplets in the tissue center and more and larger in the periphery. The activity of vagus nerve was 19,9% greater in the small litter than in control (p<0.01), and no difference was observed in the sympathetic nerve activity. In adulthood, the small litter rats were 11,7% heavier than the controls and presented higher glycemia 13,1%, insulinemia 70% and corticosteronemia 92,6%. Early overfeeding programming of obesity changes the interscapular brown adipose tissue structure in adulthood, leading to local thermogenesis hypoactivity, which may contribute to obesity in adults. © 2013 S. Karger AG, Basel.

Similar metabolic responses to calorie restriction in lean and obese Zucker rats.

Science.gov (United States)

Chiba, Takuya; Komatsu, Toshimitsu; Nakayama, Masahiko; Adachi, Toshiyuki; Tamashiro, Yukari; Hayashi, Hiroko; Yamaza, Haruyoshi; Higami, Yoshikazu; Shimokawa, Isao

2009-10-15

Calorie restriction (CR), which is thought to be largely dependent on the neuroendocrine system modulated by insulin/insulin-like growth factor-I (IGF-I) and leptin signaling, decreases morbidity and increases lifespan in many organisms. To elucidate whether insulin and leptin sensitivities are indispensable in the metabolic adaptation to CR, we investigated the effects of CR on obese Zucker (fa/fa) rats and lean control (+/+) rats. CR did not fully improve insulin resistance in (fa/fa) rats. Nonetheless, CR induced neuropeptide Y (NPY) expression in the hypothalamic arcuate nucleus and metabolism related gene expression changes in the liver in (fa/fa) rats and (+/+) rats. Up-regulation of NPY augmented plasma corticosterone levels and suppressed pituitary growth hormone (GH) expression, thereby modulating adipocytokine production to induce tissue-specific insulin sensitivity. Thus, central NPY activation via peripheral signaling might play a crucial role in the effects of CR, even in insulin resistant and leptin receptor deficient conditions.

Chronic vitamin A-enriched diet feeding regulates hypercholesterolaemia through transcriptional regulation of reverse cholesterol transport pathway genes in obese rat model of WNIN/GR-Ob strain

Directory of Open Access Journals (Sweden)

Shanmugam M Jeyakumar

2016-01-01

Full Text Available Background & objectives: Hepatic scavenger receptor class B1 (SR-B1, a high-density lipoprotein (HDL receptor, is involved in the selective uptake of HDL-associated esterified cholesterol (EC, thereby regulates cholesterol homoeostasis and improves reverse cholesterol transport. Previously, we reported in euglycaemic obese rats (WNIN/Ob strain that feeding of vitamin A-enriched diet normalized hypercholesterolaemia, possibly through hepatic SR-B1-mediated pathway. This study was aimed to test whether it would be possible to normalize hypercholesterolaemia in glucose-intolerant obese rat model (WNIN/GR/Ob through similar mechanism by feeding identical vitamin A-enriched diet. Methods: In this study, 30 wk old male lean and obese rats of WNIN/GR-Ob strain were divided into two groups and received either stock diet or vitamin A-enriched diet (2.6 mg or 129 mg vitamin A/kg diet for 14 wk. Blood and other tissues were collected for various biochemical analyses. Results: Chronic vitamin A-enriched diet feeding decreased hypercholesterolaemia and normalized abnormally elevated plasma HDL-cholesterol (HDL-C levels in obese rats as compared to stock diet-fed obese groups. Further, decreased free cholesterol (FC and increased esterified cholesterol (EC contents of plasma cholesterol were observed, which were reflected in higher EC to FC ratio of vitamin A-enriched diet-fed obese rats. However, neither lecithin-cholesterol acyltransferase (LCAT activity of plasma nor its expression (both gene and protein in the liver were altered. On the contrary, hepatic cholesterol levels significantly increased in vitamin A-enriched diet fed obese rats. Hepatic SR-B1 expression (both mRNA and protein remained unaltered among groups. Vitamin A-enriched diet fed obese rats showed a significant increase in hepatic low-density lipoprotein receptor mRNA levels, while the expression of genes involved in HDL synthesis, namely, ATP-binding cassette protein 1 (ABCA1 and

Obesity reduces bone density associated with activation of PPARγ and suppression of Wnt/β-catenin in rapidly growing male rats.

Directory of Open Access Journals (Sweden)

Jin-Ran Chen

Full Text Available BACKGROUND: It is well established that excessive consumption of a high fat diet (HFD results in obesity; however, the consequences of obesity on postnatal skeletal development have not been well studied. METHODOLOGY AND PRINCIPAL FINDINGS: Total enteral nutrition (TEN was used to feed postnatal day 27 male rats intragastrically with a high 45% fat diet (HFD for four weeks to induce obesity. Fat mass was increased compared to rats fed TEN diets containing 25% fat (medium fat diet, MFD or a chow diet (low fat diet, LFD fed ad libitum with matched body weight gains. Serum leptin and total non-esterified fatty acids (NEFA were elevated in HFD rats, which also had reduced bone mass compared to LFD-fed animals. This was accompanied by decreases in bone formation, but increases in the bone resorption. Bone marrow adiposity and expression of adipogenic genes, PPARγ and aP2 were increased, whereas osteoblastogenic markers osteocalcin and Runx2 were decreased, in bone in HFD rats compared to LFD controls. The diversion of stromal cell differentiation in response to HFD stemmed from down-regulation of the key canonical Wnt signaling molecule β-catenin protein and reciprocal up-regulation of nuclear PPARγ expression in bone. In a set of in vitro studies using pluripotent ST2 bone marrow mesenchymal stromal cells treated with serum from rats on the different diets or using the free fatty acid composition of NEFA quantified in rat serum from HFD-fed animals by GC-MS, we were able to recapitulate our in vivo findings. CONCLUSIONS/SIGNIFICANCE: These observations strongly suggest that increased NEFA in serum from rats made obese by HFD-feeding impaired bone formation due to stimulation of bone marrow adipogenesis. These effects of obesity on bone in early life may result in impaired attainment of peak bone mass and therefore increase the prevalence of osteoporosis later on in life.

Green tea polyphenols change the profile of inflammatory cytokine release from lymphocytes of obese and lean rats and protect against oxidative damage.

Science.gov (United States)

Molina, N; Bolin, A P; Otton, R

2015-10-01

This study aimed to investigate whether green tea polyphenols (GT) modulate some functional parameters of lymphocytes from obese rats. Male Wistar rats were treated with GT by gavage (12 weeks/5 days/week; 500 mg/kg of body weight) and obesity was induced by cafeteria diet (8 weeks). Lymphocytes were obtained from mesenteric lymph nodes for analyses. In response to the cafeteria diet we observed an increase in activity of the metabolic enzyme hexokinase, ROS production, MnSOD, CuZnSOD and GR enzyme activities and proliferation capacity of the cells (baseline), whereas IL-10 production was decreased. Obese rats treated with GT decreased cell proliferation (under ConA stimulation). Hexokinase and G6PDH activity, ROS production and MnSOD, CuZnSOD, GPx and GR enzymes remained increased, accompanied by an increase in Nrf2 mRNA level. There was a decrease in pro-inflammatory IL-2, IL-6, IL-1β, TNF-α cytokines that were accompanied by a decrease in the mRNA level of TRL4 while IL-10 production was increased in obese rats treated with GT. GT treatment of lean rats showed similar results to that of obese rats treated with GT, indicating that the effects of GT are independent of diet. Foxp3 and IRF4 mRNA levels were increased by GT. In conclusion, cafeteria diet modulated the function of lymphocytes from lymph nodes, increasing ROS production and decreasing anti-inflammatory IL-10, which could contribute to the inflammatory state in obesity. GT reduced ROS production, improving the redox status and reducing pro-inflammatory cytokine production by lymphocytes, suggesting that GT treatment may be driving lymphocytes to a more anti-inflammatory than pro-inflammatory microenvironment. Copyright © 2015 Elsevier B.V. All rights reserved.

Resistant starch and exercise independently attenuate weight regain on a high fat diet in a rat model of obesity

Directory of Open Access Journals (Sweden)

Johnson Ginger C

2011-07-01

Full Text Available Abstract Background Long-term weight reduction remains elusive for many obese individuals. Resistant starch (RS and exercise may be useful for weight maintenance. The effects of RS, with or without exercise, on weight regain was examined during relapse to obesity on a high carbohydrate, high fat (HC/HF diet. Methods Obesity-prone rats were fed ad libitum for 16 weeks then weight reduced on a low fat diet to induce a 17% body weight loss (weight reduced rats. Weight reduced rats were maintained on an energy-restricted low fat diet for 18 weeks, with or without a daily bout of treadmill exercise. Rats were then allowed free access to HC/HF diet containing low (0.3% or high (5.9% levels of RS. Weight regain, energy balance, body composition, adipocyte cellularity, and fuel utilization were monitored as rats relapsed to obesity and surpassed their original, obese weight. Results Both RS and exercise independently attenuated weight regain by reducing the energy gap between the drive to eat and suppressed energy requirements. Exercise attenuated the deposition of lean mass during relapse, whereas its combination with RS sustained lean mass accrual as body weight returned. Early in relapse, RS lowered insulin levels and reduced the deposition of fat in subcutaneous adipose tissue. Exercise cessation at five weeks of relapse led to increased weight gain, body fat, subcutaneous adipocytes, and decreased lean mass; all detrimental consequences to overall metabolic health. Conclusions These data are the first to show the complimentary effects of dietary RS and regular exercise in countering the metabolic drive to regain weight following weight loss and suggest that exercise cessation, in the context of relapse on a HC/HF diet, may have dire metabolic consequences.

Cardioprotective effect of L-glutamate in obese type 2 diabetic Zucker fatty rats

DEFF Research Database (Denmark)

Povlsen, Jonas Agerlund; Løfgren, Bo; Rasmussen, Lars Ege

2009-01-01

(Wistar-Kyoto) and diabetic (Zucker diabetic fatty (ZDF)) rats, studied at 16 weeks of age. The infarct size (IS)/area-at-risk (AAR) ratio was the primary end-point. Expression of L-glutamate excitatory amino acid transporter (EAAT) 1 (mitochondrial) and EAAT3 (sarcolemmal) was determined by quantitative...... was downregulated in hearts from ZDF rats at both the mRNA and protein levels (P diabetic hearts (P obese diabetic rats have......1. Because diabetic hearts have an increased threshold for cardioprotection by ischaemic preconditioning (IPC), we hypothesized that protection by L-glutamate during reperfusion is restricted in Type 2 diabetic hearts. Previously, we found that L-glutamate-mediated postischaemic cardioprotection...

Anti-obesity effects of tea from Mangifera indica L. leaves of the Ubá variety in high-fat diet-induced obese rats.

Science.gov (United States)

Ramírez, Natalia Medina; Toledo, Renata C Lopes; Moreira, Maria E Castro; Martino, Hércia Stampini Duarte; Benjamin, Laércio Dos Anjos; de Queiroz, José H; Ribeiro, Andréia Queiroz; Ribeiro, Sônia Machado Rocha

2017-07-01

Due to the high content of bioactive compounds, herbal teas are being investigated as adjuvant in chronic disease management. Studies have shown that mango leaf tea contain mangiferin, total phenolics and antioxidants, compounds with many functional properties. Therefore, this study aims to evaluate the anti-obesity effects of tea from Mangifera indica L. leaves, Ubá variety (TML), in obese rats fed a high-fat diet (HFD). For this, adult male Wistar rats were divided into three groups (n=8): the control group (fed AIN-93 diet), obese group (fed a HFD) and treated group (fed a HFD and supplemented with TML for 8 weeks). We analysed biometric measures and serum biochemical parameters of metabolic control, inflammation and oxidative stress biomarkers, histomorphometry of visceral adipose tissue and mRNA expression of peroxisome proliferator-activated receptor gamma co-activator 1 alpha (PPAR-γ), lipoprotein lipase (LPL) and fatty acid synthase (FAS). The consumption of TML (24.7±2.1mL/day) exerted antioxidant and anti-inflammatory effects, increasing total antioxidant capacity and interleukin-10 serum concentrations, reduced abdominal fat accumulation, upregulated PPAR-γ and LPL and downregulated FAS expression. Our data suggest that TML has therapeutic potential in treating obesity and related diseases through regulating the expression of transcriptional factors and enzymes associated with adipogenesis. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Effects of yam dioscorin interventions on improvements of the metabolic syndrome in high-fat diet-induced obese rats.

Science.gov (United States)

Shih, Shen-Liang; Lin, Yin-Shiou; Lin, Shyr-Yi; Hou, Wen-Chi

2015-12-01

The metabolic syndrome (MS) is termed a cluster of multiple metabolic risk criteria which is positively correlated with cardiovascular disease and type 2 diabetes mellitus (DM). Yam dioscorins have been reported to exhibit biological activities, however, little is known their preventive effects on the MS. Therefore, a high-fat (HF) diet was used to induce Wistar rat obesity and then yam dioscorin (50 mg/kg, dio50) was intervened daily concurrent HF diet (HF diet + dio50) for five weeks to check the changes of weights of body and tissues, blood pressures, and impaired glucose tolerances. The in vitro peptic hydrolysates of dioscorin with molecular mass between 3 kDa and 10 kDa and less than 3 kDa were used to determine dipeptidyl peptidase IV (DPP IV) inhibitory activities which DPP IV inhibitor has been reported to prevent and treat type 2 DM. There were no significant difference in body weights, feed intakes, feed conversion, and weights of adipose tissues of obese rats in groups of HF and (HF diet + dio50). However, the systolic blood pressures in obese rats of 2-, 3- and 4-week dioscorin interventions were showed significantly lower (P dioscorin intervention (HF+ dio50) was showed significantly different (P dioscorin peptic hydrolysates (5 mg/ml) showed inhibitory activities against DPP IV using sitagliptin phosphate as positive controls. Yam dioscorins exhibit improved MS activities in obese rats which the related mechanisms may need further investigations.

Beneficial effects of Ginkgo biloba extract on insulin signaling cascade, dyslipidemia, and body adiposity of diet-induced obese rats

Directory of Open Access Journals (Sweden)

R.M. Banin

2014-09-01

Full Text Available Ginkgo biloba extract (GbE has been indicated as an efficient medicine for the treatment of diabetes mellitus type 2. It remains unclear if its effects are due to an improvement of the insulin signaling cascade, especially in obese subjects. The aim of the present study was to evaluate the effect of GbE on insulin tolerance, food intake, body adiposity, lipid profile, fasting insulin, and muscle levels of insulin receptor substrate 1 (IRS-1, protein tyrosine phosphatase 1B (PTP-1B, and protein kinase B (Akt, as well as Akt phosphorylation, in diet-induced obese rats. Rats were fed with a high-fat diet (HFD or a normal fat diet (NFD for 8 weeks. After that, the HFD group was divided into two groups: rats gavaged with a saline vehicle (HFD+V, and rats gavaged with 500 mg/kg of GbE diluted in the saline vehicle (HFD+Gb. NFD rats were gavaged with the saline vehicle only. At the end of the treatment, the rats were anesthetized, insulin was injected into the portal vein, and after 90s, the gastrocnemius muscle was removed. The quantification of IRS-1, Akt, and Akt phosphorylation was performed using Western blotting. Serum levels of fasting insulin and glucose, triacylglycerols and total cholesterol, and LDL and HDL fractions were measured. An insulin tolerance test was also performed. Ingestion of a hyperlipidic diet promoted loss of insulin sensitivity and also resulted in a significant increase in body adiposity, plasma triacylglycerol, and glucose levels. In addition, GbE treatment significantly reduced food intake and body adiposity while it protected against hyperglycemia and dyslipidemia in diet-induced obesity rats. It also enhanced insulin sensitivity in comparison to HFD+V rats, while it restored insulin-induced Akt phosphorylation, increased IRS-1, and reduced PTP-1B levels in gastrocnemius muscle. The present findings suggest that G. biloba might be efficient in preventing and treating obesity-induced insulin signaling impairment.

Beneficial effects of Ginkgo biloba extract on insulin signaling cascade, dyslipidemia, and body adiposity of diet-induced obese rats

International Nuclear Information System (INIS)

Banin, R.M.; Hirata, B.K.S.; Andrade, I.S.; Zemdegs, J.C.S.; Clemente, A.P.G.; Dornellas, A.P.S.; Boldarine, V.T.; Estadella, D.; Albuquerque, K.T.; Oyama, L.M.; Ribeiro, E.B.; Telles, M.M.

2014-01-01

Ginkgo biloba extract (GbE) has been indicated as an efficient medicine for the treatment of diabetes mellitus type 2. It remains unclear if its effects are due to an improvement of the insulin signaling cascade, especially in obese subjects. The aim of the present study was to evaluate the effect of GbE on insulin tolerance, food intake, body adiposity, lipid profile, fasting insulin, and muscle levels of insulin receptor substrate 1 (IRS-1), protein tyrosine phosphatase 1B (PTP-1B), and protein kinase B (Akt), as well as Akt phosphorylation, in diet-induced obese rats. Rats were fed with a high-fat diet (HFD) or a normal fat diet (NFD) for 8 weeks. After that, the HFD group was divided into two groups: rats gavaged with a saline vehicle (HFD+V), and rats gavaged with 500 mg/kg of GbE diluted in the saline vehicle (HFD+Gb). NFD rats were gavaged with the saline vehicle only. At the end of the treatment, the rats were anesthetized, insulin was injected into the portal vein, and after 90s, the gastrocnemius muscle was removed. The quantification of IRS-1, Akt, and Akt phosphorylation was performed using Western blotting. Serum levels of fasting insulin and glucose, triacylglycerols and total cholesterol, and LDL and HDL fractions were measured. An insulin tolerance test was also performed. Ingestion of a hyperlipidic diet promoted loss of insulin sensitivity and also resulted in a significant increase in body adiposity, plasma triacylglycerol, and glucose levels. In addition, GbE treatment significantly reduced food intake and body adiposity while it protected against hyperglycemia and dyslipidemia in diet-induced obesity rats. It also enhanced insulin sensitivity in comparison to HFD+V rats, while it restored insulin-induced Akt phosphorylation, increased IRS-1, and reduced PTP-1B levels in gastrocnemius muscle. The present findings suggest that G. biloba might be efficient in preventing and treating obesity-induced insulin signaling impairment

Beneficial effects of Ginkgo biloba extract on insulin signaling cascade, dyslipidemia, and body adiposity of diet-induced obese rats

Energy Technology Data Exchange (ETDEWEB)

Banin, R. M.; Hirata, B. K.S. [Departamento de Ciências Biológicas, Universidade Federal de São Paulo, Diadema, SP (Brazil); Andrade, I. S.; Zemdegs, J. C.S. [Disciplina de Fisiologia da Nutrição, Departamento de Fisiologia, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Clemente, A. P.G. [Faculdade de Nutrição, Universidade Federal de Alagoas, Maceió, AL (Brazil); Dornellas, A. P.S.; Boldarine, V. T. [Disciplina de Fisiologia da Nutrição, Departamento de Fisiologia, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Estadella, D. [Departamento de Biociências, Universidade Federal de São Paulo, Baixada Santista, SP (Brazil); Albuquerque, K. T. [Curso de Nutrição, Universidade Federal do Rio de Janeiro, Macaé, RJ (Brazil); Oyama, L. M.; Ribeiro, E. B. [Disciplina de Fisiologia da Nutrição, Departamento de Fisiologia, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Telles, M. M. [Departamento de Ciências Biológicas, Universidade Federal de São Paulo, Diadema, SP (Brazil)

2014-07-25

Ginkgo biloba extract (GbE) has been indicated as an efficient medicine for the treatment of diabetes mellitus type 2. It remains unclear if its effects are due to an improvement of the insulin signaling cascade, especially in obese subjects. The aim of the present study was to evaluate the effect of GbE on insulin tolerance, food intake, body adiposity, lipid profile, fasting insulin, and muscle levels of insulin receptor substrate 1 (IRS-1), protein tyrosine phosphatase 1B (PTP-1B), and protein kinase B (Akt), as well as Akt phosphorylation, in diet-induced obese rats. Rats were fed with a high-fat diet (HFD) or a normal fat diet (NFD) for 8 weeks. After that, the HFD group was divided into two groups: rats gavaged with a saline vehicle (HFD+V), and rats gavaged with 500 mg/kg of GbE diluted in the saline vehicle (HFD+Gb). NFD rats were gavaged with the saline vehicle only. At the end of the treatment, the rats were anesthetized, insulin was injected into the portal vein, and after 90s, the gastrocnemius muscle was removed. The quantification of IRS-1, Akt, and Akt phosphorylation was performed using Western blotting. Serum levels of fasting insulin and glucose, triacylglycerols and total cholesterol, and LDL and HDL fractions were measured. An insulin tolerance test was also performed. Ingestion of a hyperlipidic diet promoted loss of insulin sensitivity and also resulted in a significant increase in body adiposity, plasma triacylglycerol, and glucose levels. In addition, GbE treatment significantly reduced food intake and body adiposity while it protected against hyperglycemia and dyslipidemia in diet-induced obesity rats. It also enhanced insulin sensitivity in comparison to HFD+V rats, while it restored insulin-induced Akt phosphorylation, increased IRS-1, and reduced PTP-1B levels in gastrocnemius muscle. The present findings suggest that G. biloba might be efficient in preventing and treating obesity-induced insulin signaling impairment.

TRC150094 attenuates progression of nontraditional cardiovascular risk factors associated with obesity and type 2 diabetes in obese ZSF1 rats

Directory of Open Access Journals (Sweden)

Shitalkumar P Zambad

2011-01-01

Full Text Available Shitalkumar P Zambad1, Siralee Munshi2, Amita Dubey3, Ram Gupta1, Rosa Anna Busiello4, Antonia Lanni5, Fernando Goglia6, Ramesh C Gupta7, Vijay Chauthaiwale8, Chaitanya Dutt91Pharmacology, 2Cellular and Molecular Biology, 3Pre-clinical and Safety Evaluation, Torrent Research Centre, Torrent Pharmaceuticals Ltd, Gujarat, India; 4Dipartimento di Biologia, Universita degli Studi di Napoli Federico II, Naples, Italy; 5Dipartimento di Scienze della Vita, Seconda Universita di Napoli, Caserta, Italy; 6Dipartimento di Scienze Biologiche ed Ambientali, Universita del Sannio, Benevento, Italy; 7Medicinal Chemistry, 8Discovery Research, 9Clinical Research, Torrent Research Centre, Torrent Pharmaceuticals Ltd, Gujarat, IndiaAbstract: Chronic overnutrition and consequential visceral obesity is associated with a cluster of risk factors for cardiovascular disease and type 2 diabetes mellitus. Moreover, individuals who have a triad of hypertension, dysglycemia, and elevated triglycerides along with reduced high-density lipoprotein cholesterol have a greater residual cardiovascular risk even after factoring for the traditional risk factors such as age, smoking, diabetes, and elevated low-density lipoprotein cholesterol. In our previous study we demonstrated that TRC150094, when administered to rats receiving a high-fat diet, stimulated mitochondrial fatty acid oxidation (FAO and reduced visceral adiposity, opening an interesting perspective for a possible clinical application. In the present study, oral administration of TRC150094 to obese Zucker spontaneously hypertensive fatty rats (obese ZSF1 improved glucose tolerance and glycemic profile as well as attenuated a rise in blood pressure. Obese ZSF1 rats treated with TRC150094 also showed reduced hepatic steatosis, reduced progression of nephropathy, and improved skeletal muscle function. At the cellular level, TRC150094 induced a significant increase in mitochondrial respiration as well as an increased FAO in

Biochemical Study of Oxidative Stress Markers in the Liver, Kidney and Heart of High Fat Diet Induced Obesity in Rats

Directory of Open Access Journals (Sweden)

Noeman Saad A

2011-08-01

Full Text Available Abstract Background Obesity has become a leading global health problem owing to its strong association with a high incidence of diseases. Aim To induce rat obesity using high fat diet (HFD and to estimate oxidative stress markers in their liver, heart and kidney tissues in order to shed the light on the effect of obesity on these organs. Materials and methods Sixty white albino rats weighing 150-200 g were randomly divided into two equal groups; group I: received high fat diet for 16 weeks, and group II (control group: received only normal diet (rat chow for 16 weeks. Blood samples were taken for measurement of lipid profile, tissue samples from liver, heart and kidney were taken for determination of malondialdehyde (MDA, protein carbonyl (PCO, reduced glutathione (GSH levels, and the activities of glutathione S- transferase (GST glutathione peroxidase (GPx, catalase (CAT and paraoxonase1 (PON1 enzymes. Results Data showed that feeding HFD diet significantly increased final body weight and induced a state of dyslipideamia. Also our results showed a significant increase MDA and PCO levels in the hepatic, heart and renal tissues of obese rats, as well as a significant decrease in the activity of GST, GPx and PON 1 enzymes. On the other hand CAT enzyme activity showed significant decrease only in renal tissues of obese rats with non significant difference in hepatic and heart tissues. GSH levels showed significant decrease in both renal and hepatic tissues of obese animals and significant increase in their heart tissues. Correlation studies in obese animals showed a negative correlation between MDA and PCO tissue levels and the activities of GPx, GST and PON1 in all tissues and also with CAT enzyme activity in renal tissues. Also a negative correlation was detected between MDA & PCO tissues levels and GSH levels in both hepatic and renal tissues. While positive correlation was found between them and GSH levels in heart tissues. Conclusion High fat

Early Onset Inflammation in Pre-Insulin-Resistant Diet-Induced Obese Rats Does Not Affect the Vasoreactivity of Isolated Small Mesenteric Arteries

DEFF Research Database (Denmark)

Blædel, Martin; Raun, Kirsten; Boonen, Harrie C M

2012-01-01

Background: Obesity is an increasing burden affecting developed and emerging societies since it is associated with an increased risk of diabetes and consequent cardiovascular complications. Increasing evidence points towards a pivotal role of inflammation in the etiology of vascular dysfunction. ...... concomitant vascular dysfunction. The results show that inflammation and obesity are tightly associated, and that inflammation is manifested prior to significant insulin resistance and vascular dysfunction........ Our study aimed to investigate signs of inflammation and their relation to vascular dysfunction in rats receiving a high fat diet. Methods: Diet-induced obese (DIO) rats were used as a model since these rats exhibit a human pre-diabetic pathology. Oral glucose and insulin tolerance tests were...... conducted on DIO rats and their controls prior to the development of insulin resistance. Furthermore, the plasma contents of selected cytokines [macrophage chemoattractant protein (MCP-1), interleukin-6 (IL-6), and interleukin-1 (IL-1)] and the concentration of adiponectin were measured. Using wire...

High fat diet and in utero exposure to maternal obesity disrupts circadian rhythm and leads to metabolic programming of liver in rat offspring.

Directory of Open Access Journals (Sweden)

Sarah J Borengasser

Full Text Available The risk of obesity in adulthood is subject to programming beginning at conception. In animal models, exposure to maternal obesity and high fat diets influences the risk of obesity in the offspring. Among other long-term changes, offspring from obese rats develop hyperinsulinemia, hepatic steatosis, and lipogenic gene expression in the liver at weaning. However, the precise underlying mechanisms leading to metabolic dysregulation in the offspring remains unclear. Using a rat model of overfeeding-induced obesity, we previously demonstrated that exposure to maternal obesity from pre-conception to birth, is sufficient to program increased obesity risk in the offspring. Offspring of obese rat dams gain greater body weight and fat mass when fed high fat diet (HFD as compared to lean dam. Since, disruptions of diurnal circadian rhythm are known to detrimentally impact metabolically active tissues such as liver, we examined the hypothesis that maternal obesity leads to perturbations of core clock components and thus energy metabolism in offspring liver. Offspring from lean and obese dams were examined at post-natal day 35, following a short (2 wk HFD challenge. Hepatic mRNA expression of circadian (CLOCK, BMAL1, REV-ERBα, CRY, PER and metabolic (PPARα, SIRT1 genes were strongly suppressed in offspring exposed to both maternal obesity and HFD. Using a mathematical model, we identified two distinct biological mechanisms that modulate PPARα mRNA expression: i decreased mRNA synthesis rates; and ii increased non-specific mRNA degradation rate. Moreover, our findings demonstrate that changes in PPARα transcription were associated with epigenomic alterations in H3K4me3 and H3K27me3 histone marks near the PPARα transcription start site. Our findings indicated that offspring from obese rat dams have detrimental alternations to circadian machinery that may contribute to impaired liver metabolism in response to HFD, specifically via reduced PPAR�

Changes in gut microbiota in rats fed a high fat diet correlate with obesity-associated metabolic parameters.

Directory of Open Access Journals (Sweden)

Virginie Lecomte

Full Text Available The gut microbiota is emerging as a new factor in the development of obesity. Many studies have described changes in microbiota composition in response to obesity and high fat diet (HFD at the phylum level. In this study we used 16s RNA high throughput sequencing on faecal samples from rats chronically fed HFD or control chow (n = 10 per group, 16 weeks to investigate changes in gut microbiota composition at the species level. 53.17% dissimilarity between groups was observed at the species level. Lactobacillus intestinalis dominated the microbiota in rats under the chow diet. However this species was considerably less abundant in rats fed HFD (P<0.0001, this being compensated by an increase in abundance of propionate/acetate producing species. To further understand the influence of these species on the development of the obese phenotype, we correlated their abundance with metabolic parameters associated with obesity. Of the taxa contributing the most to dissimilarity between groups, 10 presented significant correlations with at least one of the tested parameters, three of them correlated positively with all metabolic parameters: Phascolarctobacterium, Proteus mirabilis and Veillonellaceae, all propionate/acetate producers. Lactobacillus intestinalis was the only species whose abundance was negatively correlated with change in body weight and fat mass. This species decreased drastically in response to HFD, favouring propionate/acetate producing bacterial species whose abundance was strongly correlated with adiposity and deterioration of metabolic factors. Our observations suggest that these species may play a key role in the development of obesity in response to a HFD.

Anti-obesity and hypoglycemic effect of ethanolic extract of Murraya koenigii (L leaves in high fatty diet rats

Directory of Open Access Journals (Sweden)

Sachin V. Tembhurne

2012-05-01

Full Text Available Objective: To evaluate the hypoglycemic and anti-obesity activities of of Murraya koenigii leaves. Method: The study was performed in high fatty diet induced obesity rats. After 15 days baseline period the treatments animals were received ethanolic extract of Murraya koenigii leaves (300 and 500 mg/kg in high fatty diet rats. All the treatments were given for one month. On 30th day all the fasted animals received an intraperitoneal injection of glucose (1 g/kg for glucose tolerance test. At the end of study body weight, total cholesterol, triglycerides, and blood glucose level were measured. Results: The results demonstrate clearly that repeated oral administration of Murraya koenigii leaves evoked a potent anti-hyperglycaemic activity in high fat diet obese rats. Postprandial hyperglycaemic peaks were significantly lower in plant-treated experimental groups. In other hand, high fatty diet group increased the both total cholesterol and triglycerides levels as compared to control group. While administration of Murraya koenigii leaves significantly decreased in both cholesterol as well as triglycerides. Conclusions: We can conclude that Murraya koenigii leaves evokes potent anti-hyperglycaemic and anti-obesity effects. This fact could support their use by the diabetes patient for controlling body weight as well as maintains the glycemic level.

Spontaneous motor activity during the development and maintenance of diet-induced obesity in the rat.

Science.gov (United States)

Levin, B E

1991-09-01

More than 80% of most daily spontaneous activities (assessed in an Omnitech activity monitor) occurred during the last hour of light and 12 h of the dark phase in 8 chow-fed male Sprague-Dawley rats. Thirty additional rats were, therefore, monitored over this 13-h period to assess the relationship of activity to the development and maintenance of diet-induced obesity (DIO) on a diet high in energy, fat and sucrose (CM diet). Nine of 20 rats became obese after 3 months on the CM diet, with 71% greater weight gain than 10 chow-fed controls. Eleven of 20 rats were diet resistant (DR), gaining the same amount of weight as chow-fed rats. Neither initial activity levels nor initial body weights on chow (Period I) differed significantly across retrospectively identified groups. After 3 months on CM diet or chow (Period II), as well as after an additional 3 months after CM diet-fed rats returned to chow (Period III), there were significant inverse correlations (r = -.606 to -.370) between body weight at the time of testing and various measures of movement in the horizontal plane. There was no relationship to dietary content nor consistent correlations of body weight or diet group to vertical movements, an indirect measure of ingestive behavior. Patterns of time spent in the vertical position were significantly different for DIO vs. DR rats in Period III, however. Thus, differences in food intake and metabolic efficiency, rather than differences in nocturnal activity, are probably responsible for the greater weight gain in DIO-prone rats placed on CM diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Combined Vildagliptin and Metformin Exert Better Cardioprotection than Monotherapy against Ischemia-Reperfusion Injury in Obese-Insulin Resistant Rats

Science.gov (United States)

Apaijai, Nattayaporn; Chinda, Kroekkiat; Palee, Siripong; Chattipakorn, Siriporn; Chattipakorn, Nipon

2014-01-01

Background Obese-insulin resistance caused by long-term high-fat diet (HFD) consumption is associated with left ventricular (LV) dysfunction and increased risk of myocardial infarction. Metformin and vildagliptin have been shown to exert cardioprotective effects. However, the effect of these drugs on the hearts under obese-insulin resistance with ischemia-reperfusion (I/R) injury is unclear. We hypothesized that combined vildagliptin and metformin provide better protective effects against I/R injury than monotherapy in obese-insulin resistant rats. Methodology Male Wistar rats were fed either HFD or normal diet. Rats in each diet group were divided into 4 subgroups to receive vildagliptin, metformin, combined vildagliptin and metformin, or saline for 21 days. Ischemia due to left anterior descending artery ligation was allowed for 30-min, followed by 120-min reperfusion. Metabolic parameters, heart rate variability (HRV), LV function, infarct size, mitochondrial function, calcium transient, Bax and Bcl-2, and Connexin 43 (Cx43) were determined. Rats developed insulin resistance after 12 weeks of HFD consumption. Vildagliptin, metformin, and combined drugs improved metabolic parameters, HRV, and LV function. During I/R, all treatments improved LV function, reduced infarct size and Bax, increased Bcl-2, and improved mitochondrial function in HFD rats. However, only combined drugs delayed the time to the first VT/VF onset, reduced arrhythmia score and mortality rate, and increased p-Cx43 in HFD rats. Conclusion Although both vildagliptin and metformin improved insulin resistance and attenuate myocardial injury caused by I/R, combined drugs provided better outcomes than single therapy by reducing arrhythmia score and mortality rate. PMID:25036861

Combined vildagliptin and metformin exert better cardioprotection than monotherapy against ischemia-reperfusion injury in obese-insulin resistant rats.

Directory of Open Access Journals (Sweden)

Nattayaporn Apaijai

Full Text Available BACKGROUND: Obese-insulin resistance caused by long-term high-fat diet (HFD consumption is associated with left ventricular (LV dysfunction and increased risk of myocardial infarction. Metformin and vildagliptin have been shown to exert cardioprotective effects. However, the effect of these drugs on the hearts under obese-insulin resistance with ischemia-reperfusion (I/R injury is unclear. We hypothesized that combined vildagliptin and metformin provide better protective effects against I/R injury than monotherapy in obese-insulin resistant rats. METHODOLOGY: Male Wistar rats were fed either HFD or normal diet. Rats in each diet group were divided into 4 subgroups to receive vildagliptin, metformin, combined vildagliptin and metformin, or saline for 21 days. Ischemia due to left anterior descending artery ligation was allowed for 30-min, followed by 120-min reperfusion. Metabolic parameters, heart rate variability (HRV, LV function, infarct size, mitochondrial function, calcium transient, Bax and Bcl-2, and Connexin 43 (Cx43 were determined. Rats developed insulin resistance after 12 weeks of HFD consumption. Vildagliptin, metformin, and combined drugs improved metabolic parameters, HRV, and LV function. During I/R, all treatments improved LV function, reduced infarct size and Bax, increased Bcl-2, and improved mitochondrial function in HFD rats. However, only combined drugs delayed the time to the first VT/VF onset, reduced arrhythmia score and mortality rate, and increased p-Cx43 in HFD rats. CONCLUSION: Although both vildagliptin and metformin improved insulin resistance and attenuate myocardial injury caused by I/R, combined drugs provided better outcomes than single therapy by reducing arrhythmia score and mortality rate.

Diet-induced obesity reduces core body temperature across the estrous cycle and pregnancy in the rat.

Science.gov (United States)

Crew, Rachael C; Waddell, Brendan J; Maloney, Shane K; Mark, Peter J

2018-04-16

Obesity during pregnancy causes adverse maternal and fetal health outcomes and programs offspring for adult-onset diseases, including cardiovascular disease. Obesity also disrupts core body temperature (T c ) regulation in nonpregnant rodents; however, it is unknown whether obesity alters normal maternal T c adaptations to pregnancy. Since T c is influenced by the circadian system, and both obesity and pregnancy alter circadian biology, it was hypothesized that obesity disrupts the normal rhythmic patterns of T c before and during gestation. Obesity was induced by cafeteria (CAF) feeding in female Wistar rats for 8 weeks prior to and during gestation, whereas control (CON) animals had free access to chow. Intraperitoneal temperature loggers measured daily T c profiles throughout the study, while maternal body composition and leptin levels were assessed near term. Daily temperature profiles were examined for rhythmic features (mesor, amplitude and acrophase) by cosine regression analysis. CAF animals exhibited increased fat mass (93%) and associated hyperleptinemia (3.2-fold increase) compared to CON animals. CAF consumption reduced the average T c (by up to 0.29°C) across the estrous cycle and most of pregnancy; however, T c for CAF and CON animals converged toward the end of gestation. Obesity reduced the amplitude of T c rhythms at estrus and proestrus and on day 8 of pregnancy, but increased the amplitude at day 20 of pregnancy. Photoperiod analysis revealed that obesity reduced T c exclusively in the light period during pre-pregnancy but only during the dark period in late gestation. In conclusion, obesity alters rhythmic T c profiles and reduces the magnitude of the T c decline late in rat gestation, which may have implications for maternal health and fetal development.

Rimonabant reduces the essential value of food in the genetically obese Zucker rat: an exponential demand analysis.

Science.gov (United States)

Rasmussen, Erin B; Reilly, William; Buckley, Jessica; Boomhower, Steven R

2012-02-01

Research on free-food intake suggests that cannabinoids are implicated in the regulation of feeding. Few studies, however, have characterized how environmental factors that affect food procurement interact with cannabinoid drugs that reduce food intake. Demand analysis provides a framework to understand how cannabinoid blockers, such as rimonabant, interact with effort in reducing demand for food. The present study examined the effects rimonabant had on demand for sucrose in obese Zucker rats when effort to obtain food varied and characterized the data using the exponential ("essential value") model of demand. Twenty-nine male (15 lean, 14 obese) Zucker rats lever-pressed under eight fixed ratio (FR) schedules of sucrose reinforcement, in which the number of lever-presses to gain access to a single sucrose pellet varied between 1 and 300. After behavior stabilized under each FR schedule, acute doses of rimonabant (1-10mg/kg) were administered prior to some sessions. The number of food reinforcers and responses in each condition was averaged and the exponential and linear demand equations were fit to the data. These demand equations quantify the value of a reinforcer by its sensitivity to price (FR) increases. Under vehicle conditions, obese Zucker rats consumed more sucrose pellets than leans at smaller fixed ratios; however, they were equally sensitive to price increases with both models of demand. Rimonabant dose-dependently reduced reinforcers and responses for lean and obese rats across all FR schedules. Data from the exponential analysis suggest that rimonabant dose-dependently increased elasticity, i.e., reduced the essential value of sucrose, a finding that is consistent with graphical depictions of normalized demand curves. Copyright © 2011 Elsevier Inc. All rights reserved.

Simultaneous characterization of metabolic, cardiac, vascular and renal phenotypes of lean and obese SHHF rats.

Science.gov (United States)

Youcef, Gina; Olivier, Arnaud; L'Huillier, Clément P J; Labat, Carlos; Fay, Renaud; Tabcheh, Lina; Toupance, Simon; Rodriguez-Guéant, Rosa-Maria; Bergerot, Damien; Jaisser, Frédéric; Lacolley, Patrick; Zannad, Faiez; Laurent Vallar; Pizard, Anne

2014-01-01

Individuals with metabolic syndrome (MetS) are prone to develop heart failure (HF). However, the deleterious effects of MetS on the continuum of events leading to cardiac remodeling and subsequently to HF are not fully understood. This study characterized simultaneously MetS and cardiac, vascular and renal phenotypes in aging Spontaneously Hypertensive Heart Failure lean (SHHF(+/?) regrouping (+/+) and (+/cp) rats) and obese (SHHF(cp/cp), "cp" defective mutant allele of the leptin receptor gene) rats. We aimed to refine the milestones and their onset during the progression from MetS to HF in this experimental model. We found that SHHF(cp/cp )but not SHHF(+/?) rats developed dyslipidemia, as early as 1.5 months of age. This early alteration in the lipidic profile was detectable concomitantly to impaired renal function (polyuria, proteinuria but no glycosuria) and reduced carotid distensibility as compared to SHHF(+/?) rats. By 3 months of age SHHFcp/cp animals developed severe obesity associated with dislipidemia and hypertension defining the onset of MetS. From 6 months of age, SHHF(+/?) rats developed concentric left ventricular hypertrophy (LVH) while SHHF(cp/cp) rats developed eccentric LVH apparent from progressive dilation of the LV dimensions. By 14 months of age only SHHF(cp/cp) rats showed significantly higher central systolic blood pressure and a reduced ejection fraction resulting in systolic dysfunction as compared to SHHF(+/?). In summary, the metabolic and hemodynamic mechanisms participating in the faster decline of cardiac functions in SHHF(cp/cp) rats are established long before their physiological consequences are detectable. Our results suggest that the molecular mechanisms triggered within the first three months after birth of SHHF(cp/cp) rats should be targeted preferentially by therapeutic interventions in order to mitigate the later HF development.

High fat diet and in utero exposure to maternal obesity disrupts circadian rhythm and leads to metabolic programming of liver in rat offspring

Science.gov (United States)

The risk of obesity in adulthood is subject to programming beginning at conception. In animal models, exposure to maternal obesity and high fat diets influences the risk of obesity in the offspring. Among other long-term changes, offspring from obese rats develop hyperinsulinemia, hepatic steatosi...

Mechanisms of the anti-obesity effects of oxytocin in diet-induced obese rats.

Directory of Open Access Journals (Sweden)

Nicolas Deblon

Full Text Available Apart from its role during labor and lactation, oxytocin is involved in several other functions. Interestingly, oxytocin- and oxytocin receptor-deficient mice develop late-onset obesity with normal food intake, suggesting that the hormone might exert a series of beneficial metabolic effects. This was recently confirmed by data showing that central oxytocin infusion causes weight loss in diet-induced obese mice. The aim of the present study was to unravel the mechanisms underlying such beneficial effects of oxytocin. Chronic central oxytocin infusion was carried out in high fat diet-induced obese rats. Its impact on body weight, lipid metabolism and insulin sensitivity was determined. We observed a dose-dependent decrease in body weight gain, increased adipose tissue lipolysis and fatty acid β-oxidation, as well as reduced glucose intolerance and insulin resistance. The additional observation that plasma oxytocin levels increased upon central infusion suggested that the hormone might affect adipose tissue metabolism by direct action. This was demonstrated using in vitro, ex vivo, as well as in vivo experiments. With regard to its mechanism of action in adipose tissue, oxytocin increased the expression of stearoyl-coenzyme A desaturase 1, as well as the tissue content of the phospholipid precursor, N-oleoyl-phosphatidylethanolamine, the biosynthetic precursor of the oleic acid-derived PPAR-alpha activator, oleoylethanolamide. Because PPAR-alpha regulates fatty acid β-oxidation, we hypothesized that this transcription factor might mediate the oxytocin effects. This was substantiated by the observation that, in contrast to its effects in wild-type mice, oxytocin infusion failed to induce weight loss and fat oxidation in PPAR-alpha-deficient animals. Altogether, these results suggest that oxytocin administration could represent a promising therapeutic approach for the treatment of human obesity and type 2 diabetes.

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

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.

Exercise reverses metabolic syndrome in high-fat diet-induced obese rats.

Science.gov (United States)

Touati, Sabeur; Meziri, Fayçal; Devaux, Sylvie; Berthelot, Alain; Touyz, Rhian M; Laurant, Pascal

2011-03-01

Chronic consumption of a high-fat diet induces obesity. We investigated whether exercise would reverse the cardiometabolic disorders associated with obesity without it being necessary to change from a high- to normal-fat diet. Sprague-Dawley rats were placed on a high-fat (HFD) or control diet (CD) for 12 wk. HFD rats were then divided into four groups: sedentary HFD (HFD-S), exercise trained (motor treadmill for 12 wk) HFD (HFD-Ex), modified diet (HFD to CD; HF/CD-S), and exercise trained with modified diet (HF/CD-Ex). Cardiovascular risk parameters associated with metabolic syndrome were measured, and contents of aortic Akt, phospho-Akt at Ser (473), total endothelial nitric oxide synthase (eNOS), and phospho-eNOS at Ser (1177) were determined by Western blotting. Chronic consumption of HFD induced a metabolic syndrome. Exercise and dietary modifications reduced adiposity, improved glucose and insulin levels and plasma lipid profile, and exerted an antihypertensive effect. Exercise was more effective than dietary modification in improving plasma levels of thiobarbituric acid-reacting substance and in correcting the endothelium-dependent relaxation to acetylcholine and insulin. Furthermore, independent of the diet used, exercise increased Akt and eNOS phosphorylation. Metabolic syndrome induced by HFD is reversed by exercise and diet modification. It is demonstrated that exercise training induces these beneficial effects without the requirement for dietary modification, and these beneficial effects may be mediated by shear stress-induced Akt/eNOS pathway activation. Thus, exercise may be an effective strategy to reverse almost all the atherosclerotic risk factors linked to obesity, particularly in the vasculature.

Arginase inhibition prevents the development of hypertension and improves insulin resistance in obese rats.

Science.gov (United States)

Peyton, Kelly J; Liu, Xiao-Ming; Shebib, Ahmad R; Johnson, Fruzsina K; Johnson, Robert A; Durante, William

2018-04-27

This study investigated the temporal activation of arginase in obese Zucker rats (ZR) and determined if arginase inhibition prevents the development of hypertension and improves insulin resistance in these animals. Arginase activity, plasma arginine and nitric oxide (NO) concentration, blood pressure, and insulin resistance were measured in lean and obese animals. There was a chronological increase in vascular and plasma arginase activity in obese ZR beginning at 8 weeks of age. The increase in arginase activity in obese animals was associated with a decrease in insulin sensitivity and circulating levels of arginine and NO. The rise in arginase activity also preceded the increase in blood pressure in obese ZR detected at 12 weeks of age. Chronic treatment of 8-week-old obese animals with an arginase inhibitor or L-arginine for 4 weeks prevented the development of hypertension and improved plasma concentrations of arginine and NO. Arginase inhibition also improved insulin sensitivity in obese ZR while L-arginine supplementation had no effect. In conclusion, arginase inhibition prevents the development of hypertension and improves insulin sensitivity while L-arginine administration only mitigates hypertension in obese animals. Arginase represents a promising therapeutic target in ameliorating obesity-associated vascular and metabolic dysfunction.

Dietary fructans, but not cellulose, decrease triglyceride accumulation in the liver of obese Zucker fa/fa rats.

Science.gov (United States)

Daubioul, Catherine; Rousseau, Nicolas; Demeure, Roger; Gallez, Bernard; Taper, Henryk; Declerck, Barbara; Delzenne, Nathalie

2002-05-01

This study was designed to compare the effects of dietary supplementation with nondigestible carbohydrates, differing in fermentability by colonic bacteria, on hepatic steatosis in growing obese Zucker rats. Male Zucker fa/fa rats were divided into three groups: a control group that received the basal diet, a fructan group that received 10 g highly fermented Synergy 1/100 g diet and a cellulose group that received 10 g poorly fermented Vivapur Microcrystalline cellulose/100 g diet. Rats consuming fructan had a lower energy intake, a lower body weight and less triacylglycerol accumulation in the liver as assessed in vivo by nuclear magnetic resonance (NMR) spectroscopy, and ex vivo by biochemical and histochemical analysis compared with the control and/or cellulose groups. The high fermentation of fructans compared with cellulose was reflected by greater cecal contents and by a twofold greater propionate concentration in the portal vein of rats fed fructan compared with those fed cellulose. By measuring the capacity of hepatocytes isolated from liver of Zucker rats to synthesize triglycerides or total lipids from different precursors, we showed that propionate, at the concentrations measured in the portal vein of rats treated with fructan, selectively decreased the incorporation of acetate into total lipids, a phenomenon that could contribute, along with the lower energy intake, to less triglyceride accumulation in the liver of obese Zucker rats fed dietary fructans.

Effects of diet supplementation with Camu-camu (Myrciaria dubia HBK McVaugh fruit in a rat model of diet-induced obesity

Directory of Open Access Journals (Sweden)

Ozanildo V Nascimento

2013-03-01

Full Text Available Amazonian Camu-camu fruit (Myrciaria dubia HBK Mc Vaugh has attracted interest from food and cosmetics industries because of its rich content of vitamin C, flavonoids and anthocyanins. The goal of this study was investigates the antiobesity action of the ingestion of the Camu-camu pulp in a rat model of diet-induced obesity. Wistar rats with obesity induced by subcutaneous injection of monosodium glutamate receiving diet ad libitum. The rats were divided in two groups: an experimental group that ingested 25 mL/day of Camu-camu pulp (CCG and a non treated group (CG. After 12 weeks, the animals were sacrificed. Blood, liver, heart, white adipose tissues were collected and weighted, biochemical and inflammatory profiles were determinate as well. Animals that received the pulp of Camu-camu reduced their weights of the fat in white adipose tissues, glucose, total cholesterol, triglycerides, LDL-c and insulin blood levels. There was an increase in HDL-c levels. No change was observed in inflammatory markers and liver enzymes. Camu-camu pulp was able to improve the biochemical profile of obesity in rats suggesting that this Amazonian fruit can be further used such a functional food ingredient in control of chronic diseases linked to obesity.

Effects of diet supplementation with Camu-camu (Myrciaria dubia HBK McVaugh) fruit in a rat model of diet-induced obesity.

Science.gov (United States)

Nascimento, Ozanildo V; Boleti, Ana P A; Yuyama, Lucia K O; Lima, Emerson S

2013-03-01

Amazonian Camu-camu fruit (Myrciaria dubia HBK Mc Vaugh) has attracted interest from food and cosmetics industries because of its rich content of vitamin C, flavonoids and anthocyanins. The goal of this study was investigates the antiobesity action of the ingestion of the Camu-camu pulp in a rat model of diet-induced obesity. Wistar rats with obesity induced by subcutaneous injection of monosodium glutamate receiving diet ad libitum. The rats were divided in two groups: an experimental group that ingested 25 mL/day of Camu-camu pulp (CCG) and a non treated group (CG). After 12 weeks, the animals were sacrificed. Blood, liver, heart, white adipose tissues were collected and weighted, biochemical and inflammatory profiles were determinate as well. Animals that received the pulp of Camu-camu reduced their weights of the fat in white adipose tissues, glucose, total cholesterol, triglycerides, LDL-c and insulin blood levels. There was an increase in HDL-c levels. No change was observed in inflammatory markers and liver enzymes. Camu-camu pulp was able to improve the biochemical profile of obesity in rats suggesting that this Amazonian fruit can be further used such a functional food ingredient in control of chronic diseases linked to obesity.

Plasma kinetics of 125I beta endorphin turnover in lean and obese Zucker rats

International Nuclear Information System (INIS)

Rodd, D.; Caston, A.L.; Green, M.H.; Farrell, P.A.

1990-01-01

Plasma clearance kinetics for Beta Endorphin (BEP) are not well-defined and no definitive data exist for lean versus obese animals. To determine such kinetic parameters, a bolus of 125 I BEP (1μCi/kg) was infused into awake lean(L) and obese(O) Zucker rats. Arterial blood samples were withdrawn initially at 20 seconds intervals and less frequently as a 3-hour experimental period progressed. Donor rat blood was infused (venous catheter) to replace withdrawn blood. At 180 minutes approximately 10% of the initial dose remained in the plasma. Clearance kinetics for 125 I BEP were analyzed by compartmental analysis. A 3-component equation (i.e., 3 compartment model) provided the best fit for both L and O groups. Plasma transit times were very rapid; however, plasma fractional catabolic rate was low. Plasma mean residence time was similar for both groups (50 minutes) as was recycle time. These data suggest that BEP kinetics are similar in L and O rats, and that this peptide may undergo extensive recycling into and out of the plasma compartment. The identity of the other two compartments requires further investigation

Differential effects of sugars and the alpha-glucosidase inhibitor acarbose (Bay g 5421) on satiety in the Zucker obese rat.

Science.gov (United States)

Maggio, C A; Decarr, L B; Vasselli, J R

1987-01-01

To examine the satiety responses of Zucker obese and lean rats to simple sugars, adult male rats were given equicaloric intragastric infusions of fructose, glucose, and sucrose. All three sugars reduced the short-term intakes of both genotypes, although no reliable between-genotype differences in the satiety effects of the sugars were observed. Within each genotype, fructose had a larger satiety effect than sucrose. To examine a potential basis for the observed effects, rats were given sucrose infusions containing the intestinal glucosidase inhibitor acarbose (Bay g 5421). In obese rats, addition of a low dose of acarbose increased the satiety effect of sucrose infusion. Delaying carbohydrate absorption via acarbose administration may alter gastrointestinal and/or postabsorptive satiety processes, and may prove useful as a probe for investigating the nature of satiety signals.

Maternal obesity increases inflammation and exacerbates damage following neonatal hypoxic-ischaemic brain injury in rats.

Science.gov (United States)

Teo, Jonathan D; Morris, Margaret J; Jones, Nicole M

2017-07-01

In humans, maternal obesity is associated with an increase in the incidence of birth related difficulties. However, the impact of maternal obesity on the severity of brain injury in offspring is not known. Recent studies have found evidence of increased glial response and inflammatory mediators in the brains as a result of obesity in humans and rodents. We hypothesised that hypoxic-ischaemic (HI) brain injury is greater in neonatal offspring from obese rat mothers compared to lean controls. Female Sprague Dawley rats were randomly allocated to high fat (HFD, n=8) or chow (n=4) diet and mated with lean male rats. On postnatal day 7 (P7), male and female pups were randomly assigned to HI injury or control (C) groups. HI injury was induced by occlusion of the right carotid artery followed by 3h exposure to 8% oxygen, at 37°C. Control pups were removed from the mother for the same duration under ambient conditions. Righting behaviour was measured on day 1 and 7 following HI. The extent of brain injury was quantified in brain sections from P14 pups using cresyl violet staining and the difference in volume between brain hemispheres was measured. Before mating, HFD mothers were 11% heavier than Chow mothers (pmaternal weight. Similar observations were made with neuronal staining showing a greater loss of neurons in the brain of offspring from HFD-mothers following HI compared to Chow. Astrocytes appeared to more hypertrophic and a greater number of microglia were present in the injured hemisphere in offspring from mothers on HFD. HI caused an increase in the proportion of amoeboid microglia and exposure to maternal HFD exacerbated this response. In the contralateral hemisphere, offspring exposed to maternal HFD displayed a reduced proportion of ramified microglia. Our data clearly demonstrate that maternal obesity can exacerbate the severity of brain damage caused by HI in neonatal offspring. Given that previous studies have shown enhanced inflammatory responses in

Bromocriptine increased operant responding for high fat food but decreased chow intake in both obesity-prone and resistant rats

Energy Technology Data Exchange (ETDEWEB)

Thanos, P.K.; Wang, G.; Thanos, P.K.; Cho, J. Kim, R.; Michaelides, M.; Primeaux, S.; Bray, G.; Wang, G.-J.; Volkow, N.D.

2010-10-27

Dopamine (DA) and DAD{sub 2} receptors (D2R) have been implicated in obesity and are thought to be involved in the rewarding properties of food. Osborne-Mendel (OM) rats are susceptible to diet induced obesity (DIO) while S5B/P (S5B) rats are resistant when given a high-fat diet. Here we hypothesized that the two strains would differ in high-fat food self-administration (FSA) and that the D2R agonist bromocriptine (BC) would differently affect their behavior. Ad-libitum fed OM and S5B/P rats were tested in a FSA operant chamber and were trained to lever press for high-fat food pellets under a fixed-ratio (FR1) and a progressive ratio (PR) schedule. After sixteen days of PR sessions, rats were treated with three different doses of BC (1, 10 and 20 mg/kg). No significant differences were found between the two strains in the number of active lever presses. BC treatment (10 mg/kg and 20 mg/kg) increased the number of active lever presses (10 mg/kg having the strongest effect) whereas it decreased rat chow intake in the home cage with equivalent effects in both strains. These effects were not observed on the day of BC administration but on the day following its administration. Our results suggest that these two strains have similar motivation for procuring high fat food using this paradigm. BC increased operant responding for high-fat pellets but decreased chow intake in both strains, suggesting that D2R stimulation may have enhanced the motivational drive to procure the fatty food while correspondingly decreasing the intake of regular food. These findings suggest that susceptibility to dietary obesity (prior to the onset of obesity) may not affect operant motivation for a palatable high fat food and that differential susceptibility to obesity may be related to differential sensitivity to D2R stimulation.

Tocotrienols and Whey Protein Isolates Substantially Increase Exercise Endurance Capacity in Diet -Induced Obese Male Sprague-Dawley Rats

Science.gov (United States)

Aguila, Jay; McConell, Glenn K.; McAinch, Andrew J.; Mathai, Michael L.

2016-01-01

Background and Aims Obesity and impairments in metabolic health are associated with reductions in exercise capacity. Both whey protein isolates (WPIs) and vitamin E tocotrienols (TCTs) exert favorable effects on obesity-related metabolic parameters. This research sought to determine whether these supplements improved exercise capacity and increased glucose tolerance in diet-induced obese rats. Methods Six week old male rats (n = 35) weighing 187 ± 32g were allocated to either: Control (n = 9), TCT (n = 9), WPI (n = 8) or TCT + WPI (n = 9) and placed on a high-fat diet (40% of energy from fat) for 10 weeks. Animals received 50mg/kg body weight and 8% of total energy intake per day of TCTs and/or WPIs respectively. Food intake, body composition, glucose tolerance, insulin sensitivity, exercise capacity, skeletal muscle glycogen content and oxidative enzyme activity were determined. Results Both TCT and WPI groups ran >50% longer (2271 ± 185m and 2195 ± 265m respectively) than the Control group (1428 ± 139m) during the run to exhaustion test (Pexercise endurance (2068 ± 104m). WPIs increased the maximum in vitro activity of beta-hydroxyacyl-CoA in the soleus muscle (Pexercise endurance by 50% in sedentary, diet-induced obese rats. These positive effects of TCTs and WPIs were independent of body weight, adiposity or glucose tolerance. PMID:27058737

Effect of repeated fasting/refeeding on obesity development and health complications in rats arising from reduced nest.

Science.gov (United States)

Mozeš, Štefan; Šefčíková, Zuzana; Raček, Ľubomír

2015-02-01

Overnutrition during postnatal life represents a risk factor for later obesity and associated metabolic disorders. We investigated the interaction between postnatal and later-life nutrition on body composition, blood pressure and the jejunal enzyme activities in male Sprague-Dawley rats. From birth, we adjusted the number of pups in the nest to 4 (small litters-SL; overfeeding) or to 10 pups (normal litters-NL; controls), and from day 50 until 70, the SL (SL-R) and NL (NL-R) rats were subjected to 1 day fasting and 1 day refeeding cycles (RFR). Their body composition was determined by magnetic resonance imaging, and enzyme activity was assayed histochemically. At 50 and 70 days, SL rats were found to be overweight (p obesity risk. Accordingly, in these animals, efficient fat deposition and elevated blood pressure were not diminished in response to dietary restrictions in later life.

Mechanisms of lower maintenance dose of tacrolimus in obese patients.

Science.gov (United States)

Sawamoto, Kazuki; Huong, Tran T; Sugimoto, Natsumi; Mizutani, Yuka; Sai, Yoshimichi; Miyamoto, Ken-ichi

2014-01-01

A retrospective analysis suggested that blood tacrolimus concentrations were consistent among patients with a body mass index (BMI) that was lean (maintenance dose of tacrolimus in patients with BMI ≥ 25 was significantly lower compared with that in patients with a BMI of less than 25. Lean and obese Zucker rats fed a normal diet were given tacrolimus intravenously or orally. The blood concentrations of tacrolimus in obese rats were significantly higher than those in lean rats after administration via both routes. The moment analysis has suggested that CLtot and Vdss of tacrolimus were not significantly different between lean and obese rats. The bioavailability was higher in obese rats, compared with that in lean rats. The protein expression of Cyp3a2 in the liver was significantly decreased in obese rats, compared with lean rats, while P-gp in the small intestine was also significantly decreased in obese rats. These results suggested that the steady-state trough concentration of tacrolimus in obese patients was well maintained by a relatively low dose compared with that in normal and lean patients, presumably due to increased bioavailability.

Diet-induced obesity, exogenous leptin-, and MADB106 tumor cell challenge affect tissue leukocyte distribution and serum levels of cytokines in F344 rats.

Science.gov (United States)

Behrendt, Patrick; Buchenauer, Tobias; Horn, Rüdiger; Brabant, Georg; Jacobs, Roland; Bode, Felix; Stephan, Michael; Nave, Heike

2010-08-01

The adipocyte-derived catabolic protein leptin alters cell-mediated immunity and cytokine crosstalk. This may provide new insights into the altered immune response, seen in obese individuals. Therefore, we determined the tissue distribution of immune cells in diet-induced obese (dio) and normal weight F344 rats challenged with MADB106 tumor cells or leptin. Immune cell distribution in blood (by FACS analysis) and tissues (NK cells in spleen and liver, immunohistologically) as well as pro-inflammatory cytokines (IL-6, TNF-α; by flow cytometry) were investigated in 28 normal weight and 28 dio rats (n = 4-6/group). Pro-inflammatory cytokines were increased 3-fold for IL-6 and 7-fold for TNF-α in obese animals. Higher numbers of blood monocytes and NK cells were found in obese as compared to normal weight animals. In dio rats challenged with leptin and MADB106 tumor cells, monocyte numbers were decreased as compared to the obese control animals. Immunohistochemistry revealed an altered NK cell distribution in a compartment-, treatment-, and bodyweight-specific manner. In conclusion, our data reveal a distinct distribution pattern of monocytes and NK cells in dio rats as compared to normal weight littermates and an additional modulatory effect of a leptin- and MADB106 tumor cell challenge.

A Novel Wistar Rat Model of Obesity-Related Nonalcoholic Fatty Liver Disease Induced by Sucrose-Rich Diet

Directory of Open Access Journals (Sweden)

Maria Luíza R. P. Lima

2016-01-01

Full Text Available The pathogenesis of nonalcoholic fatty liver disease (NAFLD is not fully understood, and experimental models are an alternative to study this issue. We investigated the effects of a simple carbohydrate-rich diet on the development of obesity-related NAFLD and the impact of physical training on the metabolic abnormalities associated with this disorder. Sixty Wistar rats were randomly separated into experimental and control groups, which were fed with sucrose-enriched (18% simple carbohydrates and standard diet, respectively. At the end of each experimental period (5, 10, 20, and 30 weeks, 6 animals from each group were sacrificed for blood tests and liver histology and immunohistochemistry. From weeks 25 to 30, 6 animals from each group underwent physical training. The experimental group animals developed obesity and NAFLD, characterized histopathologically by steatosis and hepatocellular ballooning, clinically by increased thoracic circumference and body mass index associated with hyperleptinemia, and metabolically by hyperglycemia, hyperinsulinemia, hypertriglyceridemia, increased levels of very low-density lipoprotein- (VLDL- cholesterol, depletion of the antioxidants liver enzymes superoxide dismutase and catalase, and increased hepatic levels of malondialdehyde, an oxidative stress marker. Rats that underwent physical training showed increased high-density lipoprotein- (HDL- cholesterol levels. In conclusion, a sucrose-rich diet induced obesity, insulin resistance, oxidative stress, and NAFLD in rats.

Differential effects of calorie restriction and involuntary wheel running on body composition and bone structure in diet-induced obese rats

Science.gov (United States)

Weight reduction is recommended to reduce obesity-related health disorders. This study investigated the differential effects of weight reduction through caloric restriction and/or physical activity on bone structure and molecular characteristics of bone metabolism in an obese rat model. We tested th...

Sex-Differences in Renal Expression of Selected Transporters and Transcription Factors in Lean and Obese Zucker Spontaneously Hypertensive Fatty Rats

Directory of Open Access Journals (Sweden)

Andrea Babelova

2015-01-01

Full Text Available The aim of this study was to identify sex-dependent expression of renal transporter mRNA in lean and obese Zucker spontaneously hypertensive fatty (ZSF1 rats and to investigate the interaction of the most altered transporter, organic anion transporter 2 (Oat2, with diabetes-relevant metabolites and drugs. Higher incidence of glomerulosclerosis, tubulointerstitial fibrosis, and protein casts in Bowman’s space and tubular lumen was detected by PAS staining in obese male compared to female ZSF1 rats. Real-time PCR on RNA isolated from kidney cortex revealed that Sglt1-2, Oat1-3, and Oct1 were higher expressed in kidneys of lean females. Oct2 and Mrp2 were higher expressed in obese males. Renal mRNA levels of transporters were reduced with diabetic nephropathy in females and the expression of transcription factors Hnf1β and Hnf4α in both sexes. The highest difference between lean and obese ZSF1 rats was found for Oat2. Therefore, we have tested the interaction of human OAT2 with various substances using tritium-labeled cGMP. Human OAT2 showed no interaction with diabetes-related metabolites, diabetic drugs, and ACE-inhibitors. However, OAT2-dependent uptake of cGMP was inhibited by furosemide. The strongly decreased expression of Oat2 and other transporters in female diabetic ZSF1 rats could possibly impair renal drug excretion, for example, of furosemide.

A comparison of effects of lard and hydrogenated vegetable shortening on the development of high-fat diet-induced obesity in rats.

Science.gov (United States)

Kubant, R; Poon, A N; Sánchez-Hernández, D; Domenichiello, A F; Huot, P S P; Pannia, E; Cho, C E; Hunschede, S; Bazinet, R P; Anderson, G H

2015-12-14

Obesity is associated with increased consumption and preference for dietary fat. Experimental models of fat-induced obesity use either lard or vegetable shortening. Yet, there are no direct comparisons of these commonly used fat sources, or the influence of their fatty acid composition, on the development of diet-induced obesity. To compare the effects of lard and hydrogenated vegetable-shortening diets, which differ in their fatty acid composition, on weight gain and the development of obesity and insulin resistance in rats. Male Wistar rats were fed ad libitum for 14 weeks high-fat diets containing either (1) high vegetable fat (HVF, 60 kcal% from vegetable shortening) or (2) high lard fat (HLF, 60 kcal% from lard). Rats fed normal-fat (NF, 16 kcal% from vegetable shortening) diet served as control. Body weight, food intake, adipose tissue mass, serum 25[OH]D3, glucose, insulin and fatty acid composition of diets were measured. Rats fed either of the two high-fat diets had higher energy intake, weight gain and fat accretion than rats fed normal-fat diet. However, rats fed the HLF diet consumed more calories and gained more weight and body fat with greater increases of 32% in total (158.5±8.2 vs 120.2±6.6 g, P<0.05), 30% in visceral (104.4±5.2 vs 80.3±4.2 g, P<0.05) and 36% in subcutaneous fat mass (54.1±3.6 vs 39.9±3.1 g, P<0.05), compared with rats fed the HVF diet. Higher visceral adiposity was positively correlated with serum insulin (r=0.376, P<0.05) and homeostatic model assessment insulin resistance (r=0.391, P<0.05). We conclude that lard-based high-fat diets accentuate the increase in weight gain and the development of obesity and insulin resistance more than hydrogenated vegetable-shortening diets. These results further point to the importance of standardizing fatty acid composition and type of fat used in determining outcomes of consuming high-fat diets.

Differential response of rat strains to obesogenic diets underlines the importance of genetic makeup of an individual towards obesity.

Science.gov (United States)

Mn, Muralidhar; Smvk, Prasad; Battula, Kiran Kumar; Nv, Giridharan; Kalashikam, Rajender Rao

2017-08-22

Obesity, a multifactorial disorder, results from a chronic imbalance of energy intake vs. expenditure. Apart from excessive consumption of high calorie diet, genetic predisposition also seems to be equally important for the development of obesity. However, the role of genetic predisposition in the etiology of obesity has not been clearly delineated. The present study addresses this problem by selecting three rat strains (WNIN, F-344, SD) with different genetic backgrounds and exposing them to high calorie diets. Rat strains were fed HF, HS, and HFS diets and assessed for physical, metabolic, biochemical, inflammatory responses, and mRNA expression. Under these conditions: significant increase in body weight, visceral adiposity, oxidative stress and systemic pro-inflammatory status; the hallmarks of central obesity were noticed only in WNIN. Further, they developed altered glucose and lipid homeostasis by exhibiting insulin resistance, impaired glucose tolerance, dyslipidemia and fatty liver condition. The present study demonstrates that WNIN is more prone to develop obesity and associated co-morbidities under high calorie environment. It thus underlines the cumulative role of genetics (nature) and diet (nurture) towards the development of obesity, which is critical for understanding this epidemic and devising new strategies to control and manage this modern malady.

Colesevelam improves insulin resistance in a diet-induced obesity (F-DIO) rat model by increasing the release of GLP-1

DEFF Research Database (Denmark)

Shang, Quan; Saumoy, Monica; Holst, Jens Juul

2009-01-01

Bile acid sequestrants have been shown to lower glucose levels in patients with type 2 diabetes. To investigate how colesevelam (CL) HCl improves hyperglycemia, studies were conducted in diet-induced obesity (F-DIO) rats, which develop insulin resistance when fed a high-energy (high fat/high sucr......Bile acid sequestrants have been shown to lower glucose levels in patients with type 2 diabetes. To investigate how colesevelam (CL) HCl improves hyperglycemia, studies were conducted in diet-induced obesity (F-DIO) rats, which develop insulin resistance when fed a high-energy (high fat...

Sustained glucagon-like peptide 1 expression from encapsulated transduced cells to treat obese diabetic rats.

Science.gov (United States)

Moralejo, Daniel; Yanay, Ofer; Kernan, Kelly; Bailey, Adam; Lernmark, Ake; Osborne, William

2011-04-01

Obesity and type 2 diabetes (T2D) are two prevalent chronic diseases that have become a major public health concern in industrialized countries. T2D is characterized by hyperglycemia and islet beta cell dysfunction. Glucagon-like peptide 1 (GLP-1) promotes β cell proliferation and neogenesis and has a potent insulinotropic effect. Leptin receptor deficient male rats are obese and diabetic and provide a model of T2D. We hypothesized that their treatment by sustained expression of GLP-1 using encapsulated cells may prevent or delay diabetes onset. Vascular smooth muscle cells (VSMC) retrovirally transduced to secrete GLP-1 were seeded into TheraCyte(TM) encapsulation devices, implanted subcutaneously and rats were monitored for diabetes. Rats that received cell implants showed mean plasma GLP-1 level of 119.3 ± 10.2pM that was significantly elevated over control values of 32.4 ± 2.9pM (P<0.001). GLP-1 treated rats had mean insulin levels of 45.9 ± 2.3ng/ml that were significantly increased over control levels of 7.3±1.5ng/ml (P<0.001). In rats treated before diabetes onset elevations in blood glucose were delayed and rats treated after onset became normoglycemic and showed improved glucose tolerance tests. Untreated diabetic rats possess abnormal islet structures characterized by enlarged islets with α-cell infiltration and multifocal vacuolization. GLP-1 treatment induced normalization of islet structures including a mantle of α-cells and increased islet mass. These data suggest that encapsulated transduced cells may offer a potential long term treatment of patients. Copyright © 2010 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Hypolipidemic, antioxidant and antiatherogenic property of sardine by-products proteins in high-fat diet induced obese rats.

Science.gov (United States)

Affane, Fouad; Louala, Sabrine; El Imane Harrat, Nour; Bensalah, Fatima; Chekkal, Hadjera; Allaoui, Amine; Lamri-Senhadji, Myriem

2018-04-15

Fish by-products valorization on account of their richness in bioactive compounds may represent a better alternative to marine products with a view to economic profitability and sustainable development. In this study, we compared the effect of sardine by-product proteins (SBy-P), with those of the fillets (SF-P) or casein (Cas), on growth parameters, serum leptin level, lipids disorders, lipid peroxidation and reverse cholesterol transport, in diet-induced obese rats. Obesity was induced by feeding rats a high-fat diet (20% sheep fat), during 12 weeks. At body weight (BW) of 400 ± 20 g, eighteen obese rats were divided into three homogenous groups and continue to consume the high-fat diet for 4 weeks containing either, 20% SBy-P, SF-P or Cas. The results showed that SBy-P, compared to SF-P and Cas, efficiently reduced food intake (FI), BW gain and serum leptin level, and improved blood lipids levels and reverse cholesterol transport by reducing total cholesterol (TC), triacylglycerols (TG) and low-density lipoprotein cholesterol (LDL-HDL 1 -C) serum levels, increasing the level of high-density lipoprotein cholesterol (HDL 2 -C and HDL 3 -C), and enhancing lecithin: cholesterol acyltransferase (LCAT) activity. Furthermore, they attenuated lipid peroxidation by increasing atheroprotective activity of the paraoxonase-1 (PON-1). Sardine by-product proteins due to their richness in certain essential amino acids, highlight weight-loss, lipid-lowering, antioxidant and anti-atherogenic potentials, contributing to the improvement of the complications associated with obesity. Copyright © 2018 Elsevier Inc. All rights reserved.

Maternal obesity induced by diet in rats permanently influences central processes regulating food intake in offspring.

Directory of Open Access Journals (Sweden)

Shona L Kirk

2009-06-01

Full Text Available Hypothalamic systems which regulate appetite may be permanently modified during early development. We have previously reported hyperphagia and increased adiposity in the adult offspring of rodents fed an obesogenic diet prior to and throughout pregnancy and lactation. We now report that offspring of obese (OffOb rats display an amplified and prolonged neonatal leptin surge, which is accompanied by elevated leptin mRNA expression in their abdominal white adipose tissue. At postnatal Day 30, before the onset of hyperphagia in these animals, serum leptin is normal, but leptin-induced appetite suppression and phosphorylation of STAT3 in the arcuate nucleus (ARC are attenuated; the level of AgRP-immunoreactivity in the hypothalamic paraventricular nucleus (PVH, which derives from neurones in the ARC and is developmentally dependent on leptin, is also diminished. We hypothesise that prolonged release of abnormally high levels of leptin by neonatal OffOb rats leads to leptin resistance and permanently affects hypothalamic functions involving the ARC and PVH. Such effects may underlie the developmental programming of hyperphagia and obesity in these rats.

A Kampo Medicine, Boi-ogi-to, Inhibits Obesity in Ovariectomized Rats

Directory of Open Access Journals (Sweden)

Jun-ichi Yamakawa

2010-01-01

Full Text Available In women facing menopause, end of menstrual activity is accompanied by lower levels of estrogen and gradual weight gain. Postmenopausal weight gain sounds an alarm for women's health and may lead to hyperlipidemia, a lipid increase and glucose intolerance. These phenomena are connected to lifestyle-related diseases such as hypertension, type II diabetes mellitus, arteriosclerosis and metabolic syndrome, making it essential to prevent weight gain in women. A Kampo medicine, Boi-ogi-to, is traditionally used to treat obese conditions, but the mechanism has not yet been investigated. In this experiment, we tested the antiobesity properties of Boi-ogi-to in ovariectomized rats by measuring changes of serum cytokine levels and adipocytokines in fat cells. After treatment with this extract for 6 weeks (20-week-old rats, we found that there was a significant weight decrease in rats treated with Boi-ogi-to as compared with that in the control group. Serum tumor necrosis factor (TNF-α levels increased significantly in a dose-dependent manner. Gene expression of adipose tissue in uterus also dose dependently showed a significant increase of TNF-α levels, suggesting that secretion of TNF-α by fat cells might play a role in the ability of Boi-ogi-to to inhibit weight gain. While peroxisome proliferators-activated receptor-γ and adiponectin levels did not show a significant difference as compared with those in the control, levels of mRNA expression showed a tendency to increase dose dependently. Resistin did not show any significant change. These results suggest that Boi-ogi-to might be useful for the prevention of obesity that occurs in women with reduction of estrogen.

Plasma kinetics of sup 125 I beta endorphin turnover in lean and obese Zucker rats

Energy Technology Data Exchange (ETDEWEB)

Rodd, D.; Caston, A.L.; Green M.H.; Farrell, P.A. (Pennsylvania State Univ., University Park (United States))

1990-02-26

Plasma clearance kinetics for Beta Endorphin (BEP) are not well-defined and no definitive data exist for lean versus obese animals. To determine such kinetic parameters, a bolus of {sup 125}I BEP (1{mu}Ci/kg) was infused into awake lean(L) and obese(O) Zucker rats. Arterial blood samples were withdrawn initially at 20 seconds intervals and less frequently as a 3-hour experimental period progressed. Donor rat blood was infused (venous catheter) to replace withdrawn blood. At 180 minutes approximately 10% of the initial dose remained in the plasma. Clearance kinetics for {sup 125}I BEP were analyzed by compartmental analysis. A 3-component equation (i.e., 3 compartment model) provided the best fit for both L and O groups. Plasma transit times were very rapid; however, plasma fractional catabolic rate was low. Plasma mean residence time was similar for both groups (50 minutes) as was recycle time. These data suggest that BEP kinetics are similar in L and O rats, and that this peptide may undergo extensive recycling into and out of the plasma compartment. The identity of the other two compartments requires further investigation.

Glucagon-like peptide-1 reduces pancreatic β-cell mass through hypothalamic neural pathways in high-fat diet-induced obese rats.

Science.gov (United States)

Ando, Hisae; Gotoh, Koro; Fujiwara, Kansuke; Anai, Manabu; Chiba, Seiichi; Masaki, Takayuki; Kakuma, Tetsuya; Shibata, Hirotaka

2017-07-17

We examined whether glucagon-like peptide-1 (GLP-1) affects β-cell mass and proliferation through neural pathways, from hepatic afferent nerves to pancreatic efferent nerves via the central nervous system, in high-fat diet (HFD)-induced obese rats. The effects of chronic administration of GLP-1 (7-36) and liraglutide, a GLP-1 receptor agonist, on pancreatic morphological alterations, c-fos expression and brain-derived neurotrophic factor (BDNF) content in the hypothalamus, and glucose metabolism were investigated in HFD-induced obese rats that underwent hepatic afferent vagotomy (VgX) and/or pancreatic efferent sympathectomy (SpX). Chronic GLP-1 (7-36) administration to HFD-induced obese rats elevated c-fos expression and BDNF content in the hypothalamus, followed by a reduction in pancreatic β-cell hyperplasia and insulin content, thus resulting in improved glucose tolerance. These responses were abolished by VgX and SpX. Moreover, administration of liraglutide similarly activated the hypothalamic neural pathways, thus resulting in a more profound amelioration of glucose tolerance than native GLP-1 (7-36). These data suggest that GLP-1 normalizes the obesity-induced compensatory increase in β-cell mass and glucose intolerance through a neuronal relay system consisting of hepatic afferent nerves, the hypothalamus, and pancreatic efferent nerves.

Kinetic parameters for plasma β-endorphin in lean and obese Zucker rats

International Nuclear Information System (INIS)

Rodd, D.; Farrell, P.A.; Caston, A.L.; Green, M.H.

1991-01-01

To determine plasma clearance kinetics for β-endorphin (BE) by empirical compartmental analysis, a bolus of radioactive labeled 125I-BE was rapidly injected into a carotid artery catheter of unanesthetized lean (L) and obese (O) Zucker rats. The plasma disappearance of 125I was followed over a 3-h period. A 3-component exponential equation provided the best fit for plasma data. Plasma transit times were very short (10 s); however, plasma fractional catabolic rate was much slower. Plasma mean residence time was similar for both groups (50 min) as was recycle time (1.3 min). These data suggest that BE plasma disappearance kinetics are similar in L and O rats

Kinetic parameters for plasma. beta. -endorphin in lean and obese Zucker rats

Energy Technology Data Exchange (ETDEWEB)

Rodd, D.; Farrell, P.A.; Caston, A.L.; Green, M.H. (Department of Exercise and Sport Science, Pennsylvania State University, University Park (USA))

1991-03-01

To determine plasma clearance kinetics for {beta}-endorphin (BE) by empirical compartmental analysis, a bolus of radioactive labeled 125I-BE was rapidly injected into a carotid artery catheter of unanesthetized lean (L) and obese (O) Zucker rats. The plasma disappearance of 125I was followed over a 3-h period. A 3-component exponential equation provided the best fit for plasma data. Plasma transit times were very short (10 s); however, plasma fractional catabolic rate was much slower. Plasma mean residence time was similar for both groups (50 min) as was recycle time (1.3 min). These data suggest that BE plasma disappearance kinetics are similar in L and O rats.

Sustained glucagon-like peptide 1 expression from encapsulated transduced cells to treat obese diabetic rats

OpenAIRE

Moralejo, Daniel; Yanay, Ofer; Kernan, Kelly; Bailey, Adam; Lernmark, Ake; Osborne, William

2011-01-01

Obesity and type 2 diabetes (T2D) are two prevalent chronic diseases that have become a major public health concern in industrialized countries. T2D is characterized by hyperglycemia and islet beta cell dysfunction. Glucagon-like peptide 1 (GLP-1) promotes β cell proliferation and neogenesis and has a potent insulinotropic effect. Leptin receptor deficient male rats are obese and diabetic and provide a model of T2D. We hypothesized that their treatment by sustained expression of GLP-1 using e...

Insulin binding and glucose transport in adipocytes of acarbose-treated Zucker lean and obese rats.

Science.gov (United States)

Vasselli, J R; Flory, T; Fried, S K

1987-01-01

The intestinal glucosidase inhibitor acarbose was administered as a dietary admix (30 mg/100 g chow diet) to male Zucker obese and lean rats. After 15 weeks, epidiymal fat pads were removed and adipocytes isolated by collagenase digestion. Equilibrium binding of A-14 tyrosine 125I-insulin, and transport of U-14C-glucose was determined was adipocytes incubated for 50 min at 37 degrees C in 0-16000 pM insulin. Insulin binding/cell was enhanced two-fold in lean (P less than 0.01) and obese (n.s.) drug groups. In drug-treated leans, increased sensitivity of glucose transport to submaximally stimulating concentrations of insulin was observed (P less than 0.02). For both genotypes, acarbose mildly decreased insulin levels and body weight gain, although adipocyte size was unaffected. Results indicate that enhanced insulin binding accompanies metabolic improvements induced by acarbose in lean Zucker rats.

Superoxide Anions and NO in the Paraventricular Nucleus Modulate the Cardiac Sympathetic Afferent Reflex in Obese Rats

Directory of Open Access Journals (Sweden)

Qing-Bo Lu

2017-12-01

Full Text Available This study was conducted to explore the hypothesis that the endogenous superoxide anions (O2− and nitric oxide (NO system of the paraventricular nucleus (PVN regulates the cardiac sympathetic afferent reflex (CSAR contributing to sympathoexcitation in obese rats induced by a high-fat diet (42% kcal as fat for 12 weeks. CSAR was evaluated by monitoring the changes of renal sympathetic nerve activity (RSNA and the mean arterial pressure (MAP responses to the epicardial application of capsaicin (CAP in anaesthetized rats. In obese rats with hypertension (OH group or without hypertension (OB group, the levels of PVN O2−, angiotensinII (Ang II, Ang II type 1 receptor (AT1R, and nicotinamide adenine dinucleotide phosphate (NADPH oxidase were elevated, whereas neural NO synthase (nNOS and NO were significantly reduced. Moreover, CSAR was markedly enhanced, which promoted the elevation of plasma norepinephrine levels. The enhanced CSAR was attenuated by PVN application of the superoxide scavenger polyethylene glycol-superoxide dismutase (PEG-SOD and the NO donor sodium nitroprusside (SNP, and was strengthened by the superoxide dismutase inhibitor diethyldithiocarbamic acid (DETC and the nNOS inhibitor N(ω-propyl-l-arginine hydrochloride (PLA; conversely, there was a smaller CSAR response to PLA or SNP in rats that received a low-fat (12% kcal diet. Furthermore, PVN pretreatment with the AT1R antagonist losartan or with PEG-SOD, but not SNP, abolished Ang II-induced CSAR enhancement. These findings suggest that obesity alters the PVN O2− and NO system that modulates CSAR and promotes sympathoexcitation.

[Exocrine function of the pancreas in rats with experimental obesity].

Science.gov (United States)

Leshchenko, I V; Shevchuk, V H; Savcheniuk, O A; Falalieieva, T M; Sukhodolia, S A; Berehova, T V

2014-01-01

The influence of neonatal administration of hyperosmolar sodium chloride and sodium glutamate on the exocrine function of the pancreas in rats has been investigated. It was observed the development of acute pancreatitis under experimental obesity. The cross-section area of acini reduced by 12%, the cross-section area of acinocytes nuclei increased by 10%, the length between the lobes of the gland has grown by 48%. The level of amylase was increased by 43%, the levels of pancreatic amylase and lipase were increased by 68% and 24%, respectively.

Periodontitis promotes the diabetic development of obese rat via miR-147 induced classical macrophage activation.

Science.gov (United States)

Xu, Ran; Zeng, Guang; Wang, Shuyong; Tao, Hong; Ren, Le; Zhang, Zhe; Zhang, Qingna; Zhao, Jinxiu; Gao, Jing; Li, Daxu

2016-10-01

Emerging evidence has indicated the bad effect of periodontal inflammation on diabetes control. However, the exact regulatory mechanisms within the association between periodontitis and diabetic development remain unclear. This study aims to investigate the function of microRNAs in regulating periodontitis-induced inflammation in an obese rat model. Experimental periodontitis was introduced into OLETF and LETO rat. Intraperitoneal glucose tolerance test was performed to detect diabetic development. Serum cytokines levels and microRNAs expression were detected by ELISA and RT-PCR analysis respectively. And, macrophages were isolated for gain- and loss-of-function studies, to investigate the regulatory mechanism of miR-147 in periodontitis-induced inflammation. Periodontitis induced proinflammatory response with classical activated macrophages in both rats, but distinctively aggravated the impaired glucose tolerance of OLETF rat with spontaneous type 2 diabetes. Analysis for serum microRNAs expression showed the distinctive and synergistic upregulation of miR-147 with periodontitis-induced effects in rats, while further experiments demonstrated the positive regulatory mechanism of miR-147 on classical activated macrophages with overexpressed proinflammatory markers, showing M1 phenotype. This study provided new evidence for the positive effect of periodontal inflammation on diabetic development, while the regulatory mechanism of miR-147 on classical macrophage activation, was verified, and presumed to contribute to the impaired glucose tolerance aggravated by periodontitis in obese rats. Besides, this study indicated the application of miR-147 for therapeutic approach in the treatment of diabetes with periodontitis. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Protective potentials of wild rice (Zizania latifolia (Griseb) Turcz) against obesity and lipotoxicity induced by a high-fat/cholesterol diet in rats.

Science.gov (United States)

Han, Shu-Fen; Zhang, Hong; Zhai, Cheng-Kai

2012-07-01

The study evaluates the protective potentials of wild rice against obesity and lipotoxicity induced by a high-fat/cholesterol diet in rats. In addition to the rats of low-fat diet group, others animals were exposed to a high-fat/cholesterol diet condition for 8 weeks. The city diet (CD) is based on the diet consumed by urban residents in modern China, which is rich in fat/cholesterol and high in carbohydrates from white rice and processed wheat starch. The chief source of dietary carbohydrates of wild rice diet (WRD) is from Chinese wild rice and other compositions are the same with CD. Rats fed CD showed elevated body and liver organ weights, lipid profiles, free fatty acids (FFA) and leptin comparable with rats fed high-fat/cholesterol diet (HFD) known to induce obesity and hyperlipidaemia in this species. However, rats consuming WRD suppressed the increase of lipid droplets accumulation, FFA, and leptin, and the decrease of lipoprotein lipase and adipose triglyceride lipase. Meanwhile, WRD prevented high-fat/cholesterol diet-induced elevation in protein expression of sterol-regulatory element binding protein-1c, and gene expression of fatty acid synthase and acetyl-CoA carboxylase. These findings indicate that wild rice as a natural food has the potentials of preventing obesity and liver lipotoxicity induced by a high-fat/cholesterol diet in rats. Copyright © 2012 Elsevier Ltd. All rights reserved.

Daily Intake of Grape Powder Prevents the Progression of Kidney Disease in Obese Type 2 Diabetic ZSF1 Rats

Directory of Open Access Journals (Sweden)

Salwa M. K. Almomen

2017-03-01

Full Text Available Individuals living with metabolic syndrome (MetS such as diabetes and obesity are at high risk for developing chronic kidney disease (CKD. This study investigated the beneficial effect of whole grape powder (WGP diet on MetS-associated CKD. Obese diabetic ZSF1 rats, a kidney disease model with MetS, were fed WGP (5%, w/w diet for six months. Kidney disease was determined using blood and urine chemical analyses, and histology. When compared to Vehicle controls, WGP intake did not change the rat bodyweight, but lowered their kidney, liver and spleen weight, which were in parallel with the lower serum glucose and the higher albumin or albumin/globin ratio. More importantly, WGP intake improved the renal function as urination and proteinuria decreased, or it prevented kidney tissue damage in these diabetic rats. The renal protection of WGP diet was associated with up-regulation of antioxidants (Dhcr24, Gstk1, Prdx2, Sod2, Gpx1 and Gpx4 and downregulation of Txnip (for ROS production in the kidneys. Furthermore, addition of grape extract reduced H2O2-induced cell death of cultured podocytes. In conclusion, daily intake of WGP reduces the progression of kidney disease in obese diabetic rats, suggesting a protective function of antioxidant-rich grape diet against CKD in the setting of MetS.

Leptin-induced endothelium-dependent vasorelaxation of peripheral arteries in lean and obese rats: role of nitric oxide and hydrogen sulfide.

Directory of Open Access Journals (Sweden)

Anna Jamroz-Wiśniewska

Full Text Available Adipose tissue hormone leptin induces endothelium-dependent vasorelaxation mediated by nitric oxide (NO and endothelium-derived hyperpolarizing factors (EDHF. Previously it has been demonstrated that in short-term obesity the NO-dependent and the EDHF-dependent components of vascular effect of leptin are impaired and up-regulated, respectively. Herein we examined the mechanism of the EDHF-dependent vasodilatory effect of leptin and tested the hypothesis that alterations of acute vascular effects of leptin in obesity are accounted for by chronic hyperleptinemia. The study was performed in 5 groups of rats: (1 control, (2 treated with exogenous leptin for 1 week to induce hyperleptinemia, (3 obese, fed highly-palatable diet for 4 weeks, (4 obese treated with pegylated superactive rat leptin receptor antagonist (PEG-SRLA for 1 week, (5 fed standard chow and treated with PEG-SRLA. Acute effect of leptin on isometric tension of mesenteric artery segments was measured ex vivo. Leptin relaxed phenylephrine-preconstricted vascular segments in NO- and EDHF-dependent manner. The NO-dependent component was impaired and the EDHF-dependent component was increased in the leptin-treated and obese groups and in the latter group both these effects were abolished by PEG-SRLA. The EDHF-dependent vasodilatory effect of leptin was blocked by either the inhibitor of cystathionine γ-lyase, propargylglycine, or a hydrogen sulfide (H2S scavenger, bismuth (III subsalicylate. The results indicate that NO deficiency is compensated by the up-regulation of EDHF in obese rats and both effects are accounted for by chronic hyperleptinemia. The EDHF-dependent component of leptin-induced vasorelaxation is mediated, at least partially, by H2S.

The signaling mechanisms of hippocampal endoplasmic reticulum stress affecting neuronal plasticity-related protein levels in high fat diet-induced obese rats and the regulation of aerobic exercise.

Science.gov (United States)

Cai, Ming; Wang, Hong; Li, Jing-Jing; Zhang, Yun-Li; Xin, Lei; Li, Feng; Lou, Shu-Jie

2016-10-01

High fat diet (HFD)-induced obesity has been shown to reduce the levels of neuronal plasticity-related proteins, specifically brain-derived neurotrophic factor (BDNF) and synaptophysin (SYN), in the hippocampus. However, the underlying mechanisms are not fully clear. Endoplasmic reticulum stress (ERS) has been reported to play a key role in regulating gene expression and protein production by affecting stress signaling pathways and ER functions of protein folding and post-translational modification in peripheral tissues of obese rodent models. Additionally, HFD that is associated with hyperglycemia could induce hippocampal ERS, thus impairing insulin signaling and cognitive health in HFD mice. One goal of this study was to determine whether hyperglycemia and hyperlipidemia could cause hippocampal ERS in HFD-induced obese SD rats, and explore the potential mechanisms of ERS regulating hippocampal BDNF and SYN proteins production. Additionally, although regular aerobic exercise could reduce central inflammation and elevate hippocampal BDNF and SYN levels in obese rats, the regulated mechanisms are poorly understood. Nrf2-HO-1 pathways play roles in anti-ERS, anti-inflammation and anti-apoptosis in peripheral tissues. Therefore, the other goal of this study was to determine whether aerobic exercise could activate Nrf2-HO-1 in hippocampus to alleviate obesity-induced hippocampal ERS, which would lead to increased BDNF and SYN levels. Male SD rats were fed on HFD for 8weeks to establish the obese model. Then, 8weeks of aerobic exercise treadmill intervention was arranged for the obese rats. Results showed that HFD-induced obesity caused hyperglycemia and hyperlipidemia, and significantly promoted hippocampal glucose transporter 3 (GLUT3) and fatty acid transport protein 1 (FATP1) protein expression. These results were associated with the activation of hippocampal ERS and ERS-mediated apoptosis. At the same time, we found that excessive hippocampal ERS not only

Positive effects of voluntary running on metabolic syndrome-related disorders in non-obese hereditary hypertriacylglycerolemic rats.

Directory of Open Access Journals (Sweden)

Vojt ch Škop

Full Text Available While metabolic syndrome is often associated with obesity, 25% of humans suffering from it are not obese and the effect of physical activity remains unclear in such cases. Therefore, we used hereditary hypertriaclyglycerolemic (HHTg rats as a unique model for studying the effect of spontaneous physical activity [voluntary running (VR] on metabolic syndrome-related disorders, such as dyslipidemia, in non-obese subjects. Adult HHTg males were fed standard (CD or high-sucrose (HSD diets ad libitum for four weeks. Within both dietary groups, some of the rats had free access to a running wheel (CD+VR, HSD+VR, whereas the controls (CD, HSD had no possibility of extra physical activity. At the end of the four weeks, we measured the effects of VR on various metabolic syndrome-associated parameters: (i biochemical parameters, (ii the content and composition of triacylglycerols (TAG, diacylglycerols (DAG, ceramides and membrane phospholipids, and (iii substrate utilization in brown adipose tissue. In both dietary groups, VR led to various positive effects: reduced epididymal and perirenal fat depots; increased epididymal adipose tissue lipolysis; decreased amounts of serum TAG, non-esterified fatty acids and insulin; a higher insulin sensitivity index. While tissue ceramide content was not affected, decreased TAG accumulation resulted in reduced and modified liver, heart and skeletal muscle DAG. VR also had a beneficial effect on muscle membrane phospholipid composition. In addition, compared with the CD group, the CD+VR rats exhibited increased fatty acid oxidation and protein content in brown adipose tissue. Our results confirm that physical activity in a non-obese model of severe dyslipidemia has many beneficial effects and can even counteract the negative effects of sucrose consumption. Furthermore, they suggest that the mechanism by which these effects are modulated involves a combination of several positive changes in lipid metabolism.

Oxidative stress-induced cognitive impairment in obesity can be reversed by vitamin D administration in rats.

Science.gov (United States)

Hajiluian, Ghazaleh; Abbasalizad Farhangi, Mahdieh; Nameni, Ghazaleh; Shahabi, Parviz; Megari-Abbasi, Mehran

2017-07-06

There is evidence that obesity leads to cognitive impairments via several markers of oxidative stress including glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase and malondialdehyde (MDA) in the hippocampus. Increased inflammatory markers in the brain have obesity triggering effects. In the current study we aimed to investigate the effects of vitamin D on cognitive function, nuclear factor (NF)-κB, tumor necrosis factor (TNF)-α concentration and markers of oxidative stress in the hippocampus of high-fat diet-induced obese rats. Forty male Wistar rats were divided into two groups: control diet (CD) and high-fat diet (HFD) for 16 weeks; then each group subdivided into two groups including: CD, CD + vitamin D, HFD and HFD + vitamin D. Vitamin D was administered at 500 IU/kg dosage for 5 weeks. Four weeks after supplementation, Morris water maze test was performed. NF-κB and TNF-α concentration in the hippocampus were determined using ELISA kits. Moreover, oxidative stress markers in the hippocampus including GPx, SOD, MDA and CAT concentrations were measured by spectrophotometry methods. HFD significantly increased TNF-α (P = 0.04) and NF-κB (P = 0.01) concentrations in the hippocampus compared with CD. Vitamin D treatment led to a significant reduction in hippocampus NF-κB concentrations in HFD + vitamin D group (P = 0.001); however, vitamin D had no effect on TNF-α concentrations. Moreover, HFD significantly induced oxidative stress by reducing GPx, SOD and increasing MDA concentrations in the hippocampus. Vitamin D supplementation in HFD group also significantly increased GPx, SOD and reduced MDA concentrations. Vitamin D improved hippocampus oxidative stress and inflammatory markers in HFD-induced obese rats and improved cognitive performance. Further studies are needed to better clarify the underlying mechanisms.

Impact of obesity on hypertension-induced cardiac remodeling: role of oxidative stress and its modulation by gemfibrozil treatment in rats.

Science.gov (United States)

Singh, Randhir; Singh, Amrit Pal; Singh, Manjeet; Krishan, Pawan

2011-01-15

This study investigated the possible synergistic role of obesity in hypertension-induced cardiac remodeling and its modulation by gemfibrozil treatment in rats. Male Wistar rats were fed a high-fat diet (HFD) for 90 days. Normal rats were subjected to hypertension by partial abdominal aortic constriction (PAAC) for 28 days. In the HFD+PAAC control group, rats on HFD were subjected to PAAC on the 62nd day and were sacrificed on the 90th day. HFD and PAAC individually resulted in significant cardiac hypertrophy and fibrosis along with increased oxidative stress and mean arterial blood pressure (MABP) in rats as evidenced by various morphological, biochemical, and histological parameters. Moreover, the HFD + PAAC control group showed marked cardiac remodeling compared to rats subjected to HFD or PAAC alone. The HFD+gemfibrozil and HFD+PAAC+gemfibrozil groups showed significant reduction in cardiac remodeling along with reduction in oxidative stress and MABP. Hence, it may be concluded that oxidative stress plays a key role in obesity-mediated synergistic effects on induction and progression of PAAC-induced cardiac remodeling, and its deleterious effects could be reversed by gemfibrozil treatment in rats through its antioxidant activity. Copyright © 2010 Elsevier Inc. All rights reserved.

Inhibition of galectin-3 ameliorates the consequences of cardiac lipotoxicity in a rat model of diet-induced obesity

Directory of Open Access Journals (Sweden)

Gema Marín-Royo

2018-02-01

Full Text Available Obesity is accompanied by metabolic alterations characterized by insulin resistance and cardiac lipotoxicity. Galectin-3 (Gal-3 induces cardiac inflammation and fibrosis in the context of obesity; however, its role in the metabolic consequences of obesity is not totally established. We have investigated the potential role of Gal-3 in the cardiac metabolic disturbances associated with obesity. In addition, we have explored whether this participation is, at least partially, acting on mitochondrial damage. Gal-3 inhibition in rats that were fed a high-fat diet (HFD for 6 weeks with modified citrus pectin (MCP; 100 mg/kg/day attenuated the increase in cardiac levels of total triglyceride (TG. MCP treatment also prevented the increase in cardiac protein levels of carnitine palmitoyl transferase IA, mitofusin 1, and mitochondrial complexes I and II, reactive oxygen species accumulation and decrease in those of complex V but did not affect the reduction in 18F-fluorodeoxyglucose uptake observed in HFD rats. The exposure of cardiac myoblasts (H9c2 to palmitic acid increased the rate of respiration, mainly due to an increase in the proton leak, glycolysis, oxidative stress, β-oxidation and reduced mitochondrial membrane potential. Inhibition of Gal-3 activity was unable to affect these changes. Our findings indicate that Gal-3 inhibition attenuates some of the consequences of cardiac lipotoxicity induced by a HFD since it reduced TG and lysophosphatidyl choline (LPC levels. These reductions were accompanied by amelioration of the mitochondrial damage observed in HFD rats, although no improvement was observed regarding insulin resistance. These findings increase the interest for Gal-3 as a potential new target for therapeutic intervention to prevent obesity-associated cardiac lipotoxicity and subsequent mitochondrial dysfunction.

Exercise training and return to a well-balanced diet activate the neuregulin 1/ErbB pathway in skeletal muscle of obese rats

Science.gov (United States)

Ennequin, Gaël; Boisseau, Nathalie; Caillaud, Kevin; Chavanelle, Vivien; Gerbaix, Maude; Metz, Lore; Etienne, Monique; Walrand, Stéphane; Masgrau, Aurélie; Guillet, Christelle; Courteix, Daniel; Niu, Airu; Li, Yi-Ping; Capel, Fréderic; Sirvent, Pascal

2015-01-01

Some studies suggest that the signalling pathway of neuregulin 1 (NRG1), a protein involved in the regulation of skeletal muscle metabolism, could be altered by nutritional and exercise interventions. We hypothesized that diet-induced obesity could lead to alterations of the NRG1 signalling pathway and that chronic exercise could improve NRG1 signalling in rat skeletal muscle. To test this hypothesis, male Wistar rats received a high fat/high sucrose (HF/HS) diet for 16 weeks. At the end of this period, NRG1 and ErbB expression/activity in skeletal muscle was assessed. The obese rats then continued the HF/HS diet or were switched to a well-balanced diet. Moreover, in both groups, half of the animals also performed low intensity treadmill exercise training. After another 8 weeks, NRG1 and ErbB expression/activity in skeletal muscle were tested again. The 16 week HF/HS diet induced obesity, but did not significantly affect the NRG1/ErbB signalling pathway in rat skeletal muscle. Conversely, after the switch to a well-balanced diet, NRG1 cleavage ratio and ErbB4 amount were increased. Chronic exercise training also promoted NRG1 cleavage, resulting in increased ErbB4 phosphorylation. This result was associated with increased protein expression and phosphorylation ratio of the metalloprotease ADAM17, which is involved in NRG1 shedding. Similarly, in vitro stretch-induced activation of ADAM17 in rat myoblasts induced NRG1 cleavage and ErbB4 activation. These results show that low intensity endurance training and well-balanced diet activate the NRG1-ErbB4 pathway, possibly via the metalloprotease ADAM17, in skeletal muscle of diet-induced obese rats. PMID:25820551

Obesity Resistance Promotes Mild Contractile Dysfunction Associated with Intracellular Ca2+ Handling

International Nuclear Information System (INIS)

Sá, Felipe Gonçalves dos Santos de; Lima-Leopoldo, Ana Paula; Jacobsen, Bruno Barcellos; Ferron, Artur Junio Togneri; Estevam, Wagner Muller; Campos, Dijon Henrique Salomé; Castardeli, Edson; Cunha, Márcia Regina Holanda da; Cicogna, Antonio Carlos; Leopoldo, André Soares

2015-01-01

Diet-induced obesity is frequently used to demonstrate cardiac dysfunction. However, some rats, like humans, are susceptible to developing an obesity phenotype, whereas others are resistant to that. To evaluate the association between obesity resistance and cardiac function, and the impact of obesity resistance on calcium handling. Thirty-day-old male Wistar rats were distributed into two groups, each with 54 animals: control (C; standard diet) and obese (four palatable high-fat diets) for 15 weeks. After the experimental protocol, rats consuming the high-fat diets were classified according to the adiposity index and subdivided into obesity-prone (OP) and obesity-resistant (OR). Nutritional profile, comorbidities, and cardiac remodeling were evaluated. Cardiac function was assessed by papillary muscle evaluation at baseline and after inotropic maneuvers. The high-fat diets promoted increase in body fat and adiposity index in OP rats compared with C and OR rats. Glucose, lipid, and blood pressure profiles remained unchanged in OR rats. In addition, the total heart weight and the weight of the left and right ventricles in OR rats were lower than those in OP rats, but similar to those in C rats. Baseline cardiac muscle data were similar in all rats, but myocardial responsiveness to a post-rest contraction stimulus was compromised in OP and OR rats compared with C rats. Obesity resistance promoted specific changes in the contraction phase without changes in the relaxation phase. This mild abnormality may be related to intracellular Ca2+ handling

The regulatory effects of fish oil and chitosan on hepatic lipogenic signals in high-fat diet-induced obese rats.

Science.gov (United States)

Chiu, Chen-Yuan; Chang, Tien-Chia; Liu, Shing-Hwa; Chiang, Meng-Tsan

2017-10-01

The present study investigated the regulatory effects of fish oil and chitosan on the signals of hepatic lipid metabolism and the postulated mechanism in high-fat diet-induced obese rats. Diet supplementation of chitosan and fish oil efficiently suppressed the increased weights in body and livers of high-fat diet-fed rats. Supplementation of chitosan and fish oil significantly decreased the activities of hepatic lipid biosynthesis-related enzymes and efficiently regulated plasma lipoprotein homeostasis. Both chitosan and fish oil significantly ameliorated the alterations in the protein expressions of hepatic lipogenic transcription factors (LXRα and PPARα), and could also significantly regulate the downstream hepatic lipogenic genes (FAS, HMGCR, CYP7A1, FATP, FABP, AOX, and ABCA) expressions in high-fat diet-fed rats. These results suggest that both fish oil and chitosan exerts downregulative effects on hepatic lipid metabolism in high-fat diet-induced obese rats via the LXRα inhibition and PPARα activation, which further affect the expressions of hepatic lipogenesis-associated genes. Copyright © 2017. Published by Elsevier B.V.

Obesity Disrupts the Rhythmic Profiles of Maternal and Fetal Progesterone in Rat Pregnancy.

Science.gov (United States)

Crew, Rachael C; Mark, Peter J; Clarke, Michael W; Waddell, Brendan J

2016-09-01

Maternal obesity increases the risk of abnormal fetal growth, but the underlying mechanisms remain unclear. Because steroid hormones regulate fetal growth, and both pregnancy and obesity markedly alter circadian biology, we hypothesized that maternal obesity disrupts the normal rhythmic profiles of steroid hormones in rat pregnancy. Obesity was established by cafeteria (CAF) feeding for 8 wk prior to mating and throughout pregnancy. Control (CON) animals had ad libitum access to chow. Daily profiles of plasma corticosterone, 11-dehydrocorticosterone, progesterone, and testosterone were measured at Days 15 and 21 of gestation (term = 23 days) in maternal (both days) and fetal (Day 21) plasma. CAF mothers exhibited increased adiposity relative to CON and showed fetal and placental growth restriction. There was no change, however, in total fetal or placental mass due to slightly larger litter sizes in CAF. Nocturnal declines in progesterone were observed in maternal (39% lower) and fetal (45% lower) plasma in CON animals, but these were absent in CAF animals. CAF mothers were hyperlipidemic at both days of gestation, but this effect was isolated to the dark period at Day 21. CAF maternal testosterone was slightly lower at Day 15 (8%) but increased above CON by Day 21 (16%). Despite elevated maternal testosterone, male fetal testosterone was suppressed by obesity on Day 21. Neither maternal nor fetal glucocorticoid profiles were affected by obesity. In conclusion, obesity disrupts rhythmic profiles of maternal and fetal progesterone, preventing the normal nocturnal decline. Obesity subtly changed testosterone profiles but did not alter maternal and fetal glucocorticoids. © 2016 by the Society for the Study of Reproduction, Inc.

Effect of dietary oils on peripheral neuropathy-related endpoints in dietary obese rats

Directory of Open Access Journals (Sweden)

Coppey L

2018-04-01

Full Text Available Lawrence Coppey,1 Eric Davidson,1 Hanna Shevalye,1 Michael E Torres,1 Mark A Yorek1–4 1Department of Internal Medicine, University of Iowa, Iowa City, IA, USA; 2Department of Veterans Affairs Iowa City Health Care System, Iowa City, IA, USA; 3Department of Veterans Affairs, Veterans Affairs Center for the Prevention and Treatment of Visual Loss, Iowa City, IA, USA; 4Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, IA, USA Purpose: This study aimed to determine the effect of dietary oils (olive, safflower, evening primrose, flaxseed, or menhaden enriched in different mono unsaturated fatty acids or polyunsaturated fatty acids on peripheral neuropathies in diet-induced obese Sprague-Dawley rats.Materials and methods: Rats at 12 weeks of age were fed a high-fat diet (45% kcal for 16 weeks. Afterward, the rats were fed diets with 50% of the kilocalories of fat derived from lard replaced by the different dietary oils. In addition, a control group fed a standard diet (4% kcal fat and a high fat fed group (45% kcal were maintained. The treatment period was 32 weeks. The endpoints evaluated included motor and sensory nerve conduction velocity, thermal sensitivity, innervation of sensory nerves in the cornea and skin, and vascular relaxation by epineurial arterioles.Results: Menhaden oil provided the greatest benefit for improving peripheral nerve damage caused by dietary obesity. Similar results were obtained when we examined acetylcholine-mediated vascular relaxation of epineurial arterioles of the sciatic nerve. Enriching the diets with fatty acids derived from the other oils provided minimal to partial improvements.Conclusion: These studies suggest that omega-3 polyunsaturated fatty acids derived from fish oil could be an effective treatment for neural and vascular complications associated with obesity. Keywords: peripheral neuropathy, fish oil, omega-3 polyunsaturated fatty acids, omega-6 polyunsaturated fatty

Obesity augments the age-induced increase in mitochondrial capacity for H(2) O(2) release in Zucker fatty rats

DEFF Research Database (Denmark)

Hey-Mogensen, Martin; Jeppesen, Jacob; Madsen, K

2012-01-01

determined and related to citrate synthase activity to determine intrinsic mitochondrial function. Mitochondrial-specific super-oxide dismuthase (MnSOD) protein content was determined in isolated mitochondria and muscle homogenate. Catalase protein content was determined in muscle homogenate. Results: Young...... was associated with increased mitochondrial hydrogenperoxide release. MnSOD tended to be higher in the obese strain in the isolated mitochondria. Regardless of age, catalase protein content was significantly lower in the obese rats. Conclusions: This study shows that the augmented increase in obesity and insulin...

PGC-1α may associated with the anti-obesity effect of taurine on rats induced by arcuate nucleus lesion.

Science.gov (United States)

Cao, Peng-juan; Jin, Yong-jun; Li, Ming-e; Zhou, Rong; Yang, Mei-zi

2016-01-01

To observe the effect of taurine treatment in rats with monosodium glutamate (MSG)-induced obesity. Rats with MSG-induced obesity were administered taurine for five weeks. The Lee's index, food intake, blood pressure, body temperature, body mass index (BMI), fat weight, and triglyceride (TG), low density lipoprotein (LDL), and high density lipoprotein (HDL) levels were compared. The PGC-1α expression levels in white and brown adipose were measured using reverse transcription polymerase chain reaction and western blotting, and pathological changes in the arcuate nucleus and liver were examined. Compared with the model group, BMI, TG, and LDL in the high and low taurine dose groups were significantly lower, while HDL was higher. Body temperature in the taurine treatment groups was higher, and blood pressure was lower. The weight of brown fat in the taurine treatment groups was significantly higher than in the model group, while the white fat weight was significantly lower. Compared with the control group, the PGC-1α levels in white and brown adipose were higher in the taurine treatment groups and more significantly up-regulated in brown adipose. This study suggests that taurine prevents obesity in MSG-treated rats and may be closely associated with energy metabolism.

Effects of Physical Exercise on the Intestinal Mucosa of Rats Submitted to a Hypothalamic Obesity Condition.

Science.gov (United States)

Gomes, J R; Freitas, J R; Grassiolli, S

2016-10-01

The small intestine plays a role in obesity as well as in satiation. However, the effect of physical exercise on the morphology and function of the small intestine during obesity has not been reported to date. This study aimed to evaluate the effects of physical exercise on morphological aspects of the rat small intestine during hypothalamic monosodium glutamate (MSG)-induced obesity. The rats were divided into four groups: Sedentary (S), Monosodium Glutamate (MSG), Exercised (E), and Exercised Monosodium Glutamate (EMSG). The MSG and EMSG groups received a daily injection of monosodium glutamate (4 g/kg) during the 5 first days after birth. The S and E groups were considered as control groups and received injections of saline. At weaning, at 21 days after birth, the EMSG and E groups were submitted to swimming practice 3 times a week until the 90th day, when all groups were sacrificed and the parameters studied recorded. Exercise significantly reduced fat deposits and the Lee Index in MSG-treated animals, and also reduced the thickness of the intestinal wall, the number of goblet cells and intestinal alkaline phosphatase activity. However, physical activity alone increased the thickness and height of villi, and the depth of the crypts. In conclusion, regular physical exercise may alter the morphology or/and functions of the small intestine, reducing the prejudicial effects of hypothalamic obesity. Anat Rec, 299:1389-1396, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Obesity Resistance Promotes Mild Contractile Dysfunction Associated with Intracellular Ca{sup 2+} Handling

Energy Technology Data Exchange (ETDEWEB)

Sá, Felipe Gonçalves dos Santos de; Lima-Leopoldo, Ana Paula; Jacobsen, Bruno Barcellos; Ferron, Artur Junio Togneri; Estevam, Wagner Muller [Centro de Educação Física e Desportos - Departamento de Desportos - Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Campos, Dijon Henrique Salomé [Departamento de Clínica Médica - Faculdade de Medicina - Universidade Estadual Paulista, Botucatu, São Paulo (Brazil); Castardeli, Edson; Cunha, Márcia Regina Holanda da [Centro de Educação Física e Desportos - Departamento de Desportos - Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Cicogna, Antonio Carlos [Departamento de Clínica Médica - Faculdade de Medicina - Universidade Estadual Paulista, Botucatu, São Paulo (Brazil); Leopoldo, André Soares, E-mail: andresoaresleopoldo@gmail.com [Centro de Educação Física e Desportos - Departamento de Desportos - Universidade Federal do Espírito Santo, Vitória, ES (Brazil)

2015-12-15

Diet-induced obesity is frequently used to demonstrate cardiac dysfunction. However, some rats, like humans, are susceptible to developing an obesity phenotype, whereas others are resistant to that. To evaluate the association between obesity resistance and cardiac function, and the impact of obesity resistance on calcium handling. Thirty-day-old male Wistar rats were distributed into two groups, each with 54 animals: control (C; standard diet) and obese (four palatable high-fat diets) for 15 weeks. After the experimental protocol, rats consuming the high-fat diets were classified according to the adiposity index and subdivided into obesity-prone (OP) and obesity-resistant (OR). Nutritional profile, comorbidities, and cardiac remodeling were evaluated. Cardiac function was assessed by papillary muscle evaluation at baseline and after inotropic maneuvers. The high-fat diets promoted increase in body fat and adiposity index in OP rats compared with C and OR rats. Glucose, lipid, and blood pressure profiles remained unchanged in OR rats. In addition, the total heart weight and the weight of the left and right ventricles in OR rats were lower than those in OP rats, but similar to those in C rats. Baseline cardiac muscle data were similar in all rats, but myocardial responsiveness to a post-rest contraction stimulus was compromised in OP and OR rats compared with C rats. Obesity resistance promoted specific changes in the contraction phase without changes in the relaxation phase. This mild abnormality may be related to intracellular Ca2+ handling.

Obesity and type 2 diabetes, not a diet high in fat, sucrose, and cholesterol, negatively impacts bone outcomes in the hyperphagic Otsuka Long Evans Tokushima Fatty rat.

Science.gov (United States)

Ortinau, Laura C; Linden, Melissa A; Dirkes, Rebecca; Rector, R Scott; Hinton, Pamela S

2017-12-01

Obesity and type 2 diabetes (T2D) increase fracture risk; however, the association between obesity/T2D may be confounded by consumption of a diet high in fat, sucrose, and cholesterol (HFSC). The study objective was to determine the main and interactive effects of obesity/T2D and a HFSC diet on bone outcomes using hyperphagic Otuska Long Evans Tokushima Fatty (OLETF) rats and normophagic Long Evans Tokushima Otsuka (LETO) controls. At 8weeks of age, male OLETF and LETO rats were randomized to either a control (CON, 10 en% from fat as soybean oil) or HFSC (45 en% from fat as soybean oil/lard, 17 en% sucrose, and 1wt%) diet, resulting in four treatment groups. At 32weeks, total body bone mineral content (BMC) and density (BMD) and body composition were measured by dual-energy X-ray absorptiometry, followed by euthanasia and collection of blood and tibiae. Bone turnover markers and sclerostin were measured using ELISA. Trabecular microarchitecture of the proximal tibia and geometry of the tibia mid-diaphysis were measured using microcomputed tomography; whole-bone and tissue-level biomechanical properties were evaluated using torsional loading of the tibia. Two-factor ANOVA was used to determine main and interactive effects of diet (CON vs. HFSC) and obesity/T2D (OLETF vs. LETO) on bone outcomes. Hyperphagic OLEFT rats had greater final body mass, body fat, and fasting glucose than normophagic LETO, with no effect of diet. Total body BMC and serum markers of bone formation were decreased, and bone resorption and sclerostin were increased in obese/T2D OLETF rats. Trabecular bone volume and microarchitecture were adversely affected by obesity/T2D, but not diet. Whole-bone and tissue-level biomechanical properties of the tibia were not affected by obesity/T2D; the HFSC diet improved biomechanical properties only in LETO rats. Obesity/T2D, regardless of diet, negatively impacted the balance between bone formation and resorption and trabecular bone volume and

Exposure to a northern contaminant mixture (NCM alters hepatic energy and lipid metabolism exacerbating hepatic steatosis in obese JCR rats.

Directory of Open Access Journals (Sweden)

Ryan J Mailloux

Full Text Available Non-alcoholic fatty liver disease (NAFLD, defined by the American Liver Society as the buildup of extra fat in liver cells that is not caused by alcohol, is the most common liver disease in North America. Obesity and type 2 diabetes are viewed as the major causes of NAFLD. Environmental contaminants have also been implicated in the development of NAFLD. Northern populations are exposed to a myriad of persistent organic pollutants including polychlorinated biphenyls, organochlorine pesticides, flame retardants, and toxic metals, while also affected by higher rates of obesity and alcohol abuse compared to the rest of Canada. In this study, we examined the impact of a mixture of 22 contaminants detected in Inuit blood on the development and progression of NAFLD in obese JCR rats with or without co-exposure to 10% ethanol. Hepatosteatosis was found in obese rat liver, which was worsened by exposure to 10% ethanol. NCM treatment increased the number of macrovesicular lipid droplets, total lipid contents, portion of mono- and polyunsaturated fatty acids in the liver. This was complemented by an increase in hepatic total cholesterol and cholesterol ester levels which was associated with changes in the expression of genes and proteins involved in lipid metabolism and transport. In addition, NCM treatment increased cytochrome P450 2E1 protein expression and decreased ubiquinone pool, and mitochondrial ATP synthase subunit ATP5A and Complex IV activity. Despite the changes in mitochondrial physiology, hepatic ATP levels were maintained high in NCM-treated versus control rats. This was due to a decrease in ATP utilization and an increase in creatine kinase activity. Collectively, our results suggest that NCM treatment decreases hepatic cholesterol export, possibly also increases cholesterol uptake from circulation, and promotes lipid accumulation and alters ATP homeostasis which exacerbates the existing hepatic steatosis in genetically obese JCR rats with

Ciprofibrate, clofibric acid and respective glycinate derivatives. Effects of a four-week treatment on male lean and obese Zucker rats.

Science.gov (United States)

Lupp, Amelie; Karge, Elke; Deufel, Thomas; Oelschlägers, Herbert; Fleck, Christian

2008-01-01

Fibrates are widely prescribed in hyperlpidemic patients to prevent atherosclerosis. Their therapeutic use, however, can be associated with adverse effects like gastrointestinal disorders, myalgia, myositis and hepatotoxicity. In rodents large doses can even cause hepatocellular carcinoma. Additionally, interactions with the biotransformation of other compounds at the cytochrome P450 (CYP) system have been observed. Thus, the discovery of new substances or derivatives with less side effects is of great interest. In the present study the influence of a four-week daily oral administration of 2 mg/kg body weight ciprofibrate (CAS 52214-84-3) or of 100 mg/kg body weight clofibric acid (CAS 882-09-7) was compared to that of the respective doses of their newly synthesized glycine conjugates in adult male lean and obese Zucker rats. Although obese rats displayed distinctly higher serum lipid concentrations, after fibrate treatment values were significantly lowered in lean animals only. Livers of obese rats were significantly enlarged, histologically showing a fine-droplet like fatty degeneration and an increase in glycogen content, but no signs of inflammation. After fibrate administration histologically a hypertrophy, an eosinophilia, a reduced glycogen content and also hepatocyteapoptosis were observed. Livers of obese rats displayed higher CYP1A1 andCYP2E1 expression, but lower immunostaining for CYP2B1 and CYP3A2. No differences between the two groups of rats were seen with respect to CYP4A1 expression. Due to fibrate treatment especially CYP2E1 and CYP4A1, but also CYP1A1, 2B1 and 3A2 were induced. Resulting CYP mediated monooxygenase activities were also elevated in most cases. In general, effects of clofibric acid and clofibric acid glycinate (CAS 4896-55-3) were less distinct than those of ciprofibrate and its glycinate (CAS 640772-36-7). With no parameterinvestigated major differences were seen between the parent fibrates and their glycine conjugates. Thus, the

Experimental model to induce obesity in rats Modelo experimental para induzir obesidade em ratos

Directory of Open Access Journals (Sweden)

Vinicius Von Diemen

2006-12-01

Full Text Available The etiology of obesity is multifactorial and is becoming a problem of public health, due to its increased prevalence and the consequent repercussion of its comorbidities on the health of the population. The great similarity and homology between the genomes of rodents and humans make these animal models a major tool to study conditions affecting humans, which can be simulated in rats. Obesity can be induced in animals by neuroendocrine, dietary or genetic changes. The most widely used models to induce obesity in rats are a lesion of the ventromedial hypothalamic nucleus (VMH by administering monosodium glutamate or a direct electrical lesion, ovariectomy, feeding on hypercaloric diets and genetic manipulation for obesity.A obesidade tem etiologia multifatorial e está se tornando um problema de saúde pública devido ao aumento da sua prevalência e a conseqüente repercusão das suas comorbidades na saúde da população. A grande similaridade e homologia entre os genomas dos roedores e dos humanos tornam esses modelos animais uma importante ferramenta para o estudo de condições que afetam os humanos e que podem ser simuladas em ratos. A obesidade pode ser induzida em animais com alterações neuroendócrinas, dietéticas ou genéticas. Os modelos mais utilizados para indução de obesidade em ratos são lesão do núcleo hipotalâmico venteromedial (VMH através da administração de glutamato monossódico ou lesão elétrica direta, ooforectomia, alimentação com dietas hipercalóricas e manipulação genética para obesidade.

Pyrrolidin-2-one derivatives may reduce body weight in rats with diet-induced obesity.

Science.gov (United States)

Dudek, Magdalena; Knutelska, Joanna; Bednarski, Marek; Nowiński, Leszek; Zygmunt, Małgorzata; Kazek, Grzegorz; Mordyl, Barbara; Głuch-Lutwin, Monika; Zaręba, Paula; Kulig, Katarzyna; Sapa, Jacek

2016-04-05

Obesity affects an increasing number of individuals in the human population and significant importance is attached to research leading to the discovery of drug which would effectively reduce weight. The search for new drugs with anorectic activity and acting within the adrenergic system has attracted the interest of researchers. This study concerns the experimental effects on body weight of α2-adrenoceptor antagonists from the group of pyrrolidin-2-one derivatives in rats with diet-induced obesity. The intrinsic activity of the test compounds at the α-adrenoreceptors was tested. Obesity in rats was obtained by the use of fatty diet and then the influence of the test compounds on body weight, food and water intakes, lipid and glucose profiles and glycerol and cortisol levels were determinated. The effects of the compounds on locomotor activity, body temperature, blood pressure and heart rate were tested. One of the test compounds (1-(3-(4-phenylpiperazin-1-yl)propyl)pyrrolidin-2-one) reduces the animal's body weight and the amount of peritoneal adipose tissue during chronic administration, at the same time it does not cause significant adverse effects on the cardiovascular system. This compound decreases temperature and elevates glycerol levels and does not change the locomotor activity and cortisol level at anti-obese dose. Some derivatives of pyrrolidin-2-one that act as antagonists of the α2-adrenoreceptor may reduce body weight. Reducing body weight for 1-(3-(4-phenylpiperazin-1-yl)propyl)pyrrolidin-2-one can be associated with decrease in food intake, body fat reduction, reduction of blood glucose, and increased thermogenesis and lipolysis. This effect cannot be the result of changes in spontaneous activity or stress. Copyright © 2016 Elsevier B.V. All rights reserved.

Determining rates of overweight and obese status in children using electronic medical records

Science.gov (United States)

Birken, Catherine S.; Tu, Karen; Oud, William; Carsley, Sarah; Hanna, Miranda; Lebovic, Gerald; Guttmann, Astrid

2017-01-01

Abstract Objective To determine the prevalence of overweight and obese status in children by age, sex, and visit type, using data from EMRALD® (Electronic Medical Record Administrative data Linked Database). Design Heights and weights were abstracted for children 0 to 19 years of age who had at least one well-child visit from January 2010 to December 2011. Using the most recent visit, the proportions and 95% CIs of patients defined as overweight and obese were compared by age group, sex, and visit type using the World Health Organization growth reference standards. Setting Ontario. Participants Children 0 to 19 years of age who were rostered to a primary care physician participating in EMRALD and had at least one well-child visit from January 2010 to December 2011. Main outcome measures Proportion and 95% CI of children with overweight and obese status by age group; proportion of children with overweight and obese status by sex (with male sex as the referent) within each age group; and proportion of children with overweight and obese status at the most recent well-child visit type compared with other visit types by age group. Results There were 28 083 well-child visits during this period. For children who attended well-child visits, 84.7% of visits had both a height and weight documented. Obesity rates were significantly higher in 1- to 4-year-olds compared with children younger than 1 (6.1% vs 2.3%; P overweight and obese status were lower using data from well-child visits compared with other visits. Conclusion Electronic medical records might be useful to conduct population-based surveillance of overweight or obese status in children. Methodologic standards, however, should be developed. PMID:28209703

Small Intestinal Bypass Induces a Persistent Weight-Loss Effect and Improves Glucose Tolerance in Obese Rats.

Science.gov (United States)

Cao, Jiaqing; Ren, Quan; Tan, Cai; Duan, Jinyuan

2017-07-01

This study investigated the role of proximal small intestinal bypass (PSIB) and distal small intestinal bypass (DSIB) as well as their long-term effects on weight loss and glucose metabolism in high-sugar and high-fat diet-induced obese rats. Sprague-Dawley rats were divided into four groups: PSIB, bypassing 60% of the proximal small intestine length; DSIB, bypassing 60% of the distal small intestine length; sham-operated (Sham) animals; and control animals. All rats were fed a high-sugar and high-fat diet after surgery. The primary outcome measures were body weight, food intake, fasting blood glucose (FBG) levels, oral glucose tolerance test (OGTT), and the insulin tolerance test (ITT). Global body weight (BW) and food intake in the PSIB and DSIB groups were lower than those in the Sham group at postoperative week 2. BW and food intake in the PSIB group were lower than those in the DSIB group at postoperative week 24. The PSIB and DSIB groups exhibited improvement in glucose tolerance at postoperative weeks 4, 8, and 24. The PSIB and DSIB groups exhibited improvement in FBG at postoperative week 24, and only the DSIB group exhibited improvement in insulin sensitivity. This study provides experimental evidence that PSIB surgery induced a better and more persistent weight loss effect than DSIB surgery and that the two types of intestinal bypass surgeries yielded equivalent and stable long-term improvement in glucose tolerance in an obese rat model.

Early Overfeed-Induced Obesity Leads to Brown Adipose Tissue Hypoactivity in Rats

Directory of Open Access Journals (Sweden)

Douglas L. de Almeida

2013-12-01

Full Text Available Background/Aims: Brown adipose tissue activation has been considered a potential anti-obesity mechanism because it is able to expend energy through thermogenesis. In contrast, white adipose tissue stores energy, contributing to obesity. We investigated whether the early programming of obesity by overfeeding during lactation changes structure of interscapular brown adipose tissue in adulthood and its effects on thermogenesis. Methods: Birth of litters was considered day 0. On day 2, litter size was adjusted to normal (9 pups and small (3 pups litters. On day 21, the litters were weaned. A temperature transponder was implanted underneath interscapular brown adipose tissue pads of 81-day-old animals; local temperature was measured during light and dark periods between days 87 and 90. The animals were euthanized, and tissue and blood samples were collected for further analysis. The vagus and retroperitoneal sympathetic nerve activity was recorded. Results: Small litter rats presented significant lower interscapular brown adipose tissue temperature during the light (NL 37.6°C vs. SL 37.2°C and dark (NL 38°C vs. SL 37.6°C periods compared to controls. Morphology of small litter brown adipose tissue showed fewer lipid droplets in the tissue center and more and larger in the periphery. The activity of vagus nerve was 19,9% greater in the small litter than in control (pConclusion: Early overfeeding programming of obesity changes the interscapular brown adipose tissue structure in adulthood, leading to local thermogenesis hypoactivity, which may contribute to obesity in adults.

Diminished metabolic responses to centrally-administered apelin-13 in diet-induced obese rats fed a high-fat diet.

Science.gov (United States)

Clarke, K J; Whitaker, K W; Reyes, T M

2009-02-01

The central administration of apelin, a recently identified adipokine, has been shown to affect food and water intake. The present study investigated whether body weight could affect an animal's response to apelin. The effects of centrally-administered apelin-13 on food and water intake, activity and metabolic rate were investigated in adult male diet-induced obese (DIO) rats fed either a high fat (32%) or control diet. Rats were administered i.c.v. apelin-13, 15-30 min prior to lights out, and food and water intake, activity and metabolic rate were assessed. Intracerebroventricular administration of apelin-13 decreased food and water intake and respiratory exchange ratio in DIO rats on the control diet, but had no effect in DIO rats on the high-fat diet. In an effort to identify potential central mechanisms explaining the observed physiological responses, the mRNA level of the apelin receptor, APJ, was examined in the hypothalamus. A high-fat diet induced an up-regulation of the expression of the receptor. Apelin induced a down-regulation of the receptor, but only in the DIO animals on the high-fat diet. In conclusion, we have demonstrated a diminished central nervous system response to apelin that is coincident with obesity.

Caloric restriction in lean and obese strains of laboratory rat: effects on body composition, metabolism, growth and overall health

Data.gov (United States)

U.S. Environmental Protection Agency — Data related to obese and lean strains of rat commonly used in the laboratory that are calorically restricted and its effects on physiologic parameters (Body...

Aerobic interval exercise improves parameters of nonalcoholic fatty liver disease (NAFLD) and other alterations of metabolic syndrome in obese Zucker rats.

Science.gov (United States)

Kapravelou, Garyfallia; Martínez, Rosario; Andrade, Ana M; Nebot, Elena; Camiletti-Moirón, Daniel; Aparicio, Virginia A; Lopez-Jurado, Maria; Aranda, Pilar; Arrebola, Francisco; Fernandez-Segura, Eduardo; Bermano, Giovanna; Goua, Marie; Galisteo, Milagros; Porres, Jesus M

2015-12-01

Metabolic syndrome (MS) is a group of metabolic alterations that increase the susceptibility to cardiovascular disease and type 2 diabetes. Nonalcoholic fatty liver disease has been described as the liver manifestation of MS. We aimed to test the beneficial effects of an aerobic interval training (AIT) protocol on different biochemical, microscopic, and functional liver alterations related to the MS in the experimental model of obese Zucker rat. Two groups of lean and obese animals (6 weeks old) followed a protocol of AIT (4 min at 65%-80% of maximal oxygen uptake, followed by 3 min at 50%-65% of maximal oxygen uptake for 45-60 min, 5 days/week, 8 weeks of experimental period), whereas 2 control groups remained sedentary. Obese rats had higher food intake and body weight (P metabolism and increased the liver protein expression of PPARγ, as well as the gene expression of glutathione peroxidase 4 (P < 0.001). The training protocol also showed significant effects on the activity of hepatic antioxidant enzymes, although this action was greatly influenced by rat phenotype. The present data suggest that AIT protocol is a feasible strategy to improve some of the plasma and liver alterations featured by the MS.

Cyclosporine A administered during reperfusion fails to restore cardioprotection in prediabetic Zucker obese rats in vivo.

Science.gov (United States)

Huhn, R; Heinen, A; Hollmann, M W; Schlack, W; Preckel, B; Weber, N C

2010-12-01

Hyperglycaemia blocks sevoflurane-induced postconditioning, and cardioprotection in hyperglycaemic myocardium can be restored by inhibition of the mitochondrial permeability transition pore (mPTP). We investigated whether sevoflurane-induced postconditioning is also blocked in the prediabetic heart and if so, whether cardioprotection could be restored by inhibiting mPTP. Zucker lean (ZL) and Zucker obese (ZO) rats were assigned to one of seven groups. Animals underwent 25 min of ischaemia and 120 min of reperfusion. Control (ZL-/ZO Con) animals were not further treated. postconditioning groups (ZL-/ZO Sevo-post) received sevoflurane for 5 min starting 1min prior to the onset of reperfusion. The mPTP inhibitor cyclosporine A (CsA) was administered intravenously in a concentration of 5 (ZO CsA and ZO CsA+Sevo-post) or 10 mg/kg (ZO CsA10+Sevo-post) 5 min before the onset of reperfusion. At the end of reperfusion, infarct sizes were measured by TTC staining. Blood samples were collected to measure plasma levels of insulin, cholesterol and triglycerides. Sevoflurane postconditioning reduced infarct size in ZL rats to 35±12% (pfailed to restore cardioprotection in the prediabetic but normoglycaemic heart of Zucker obese rats in vivo. Copyright © 2009 Elsevier B.V. All rights reserved.

The characterization of obese polycystic ovary syndrome rat model suitable for exercise intervention.

Directory of Open Access Journals (Sweden)

Chuyan Wu

Full Text Available To develop a new polycystic ovary syndrome (PCOS rat model suitable for exercise intervention.Thirty six rats were randomly divided into three experimental groups: PCOS rats with high-fat diet (PF, n = 24, PCOS rats with ordinary diet (PO, n = 6, and control rats with ordinary diet (CO, n = 6. Two kinds of PCOS rat model were made by adjustment diet structure and testosterone injection for 28 days. After a successful animal model, PF model rats were randomly assigned to three groups: exercise with a continuation of high-fat diet (PF-EF, n = 6, sedentary with a continuation of high-fat diet (PF-SF, n = 6, exercise with an ordinary diet (PF-EO, n = 6. Fasting blood glucose (FBG and insulin (FINS, estrogen (E2, progesterone (P, and testosterone (T in serum were determined by RIA, and ovarian morphology was evaluated by Image-Pro plus 6.0.Body weight, Lee index, FINS increased significantly in PF rat model. Serum levels of E2 and T were significantly higher in PF and PO than in CO. Ovary organ index and ovarian areas were significant lower in PF than in CO. After intervention for 2 weeks, the levels of 1 h postprandial blood glucose (PBG1, 2 h postprandial blood glucose (PBG2, FINS and the serum levels of T decreased significantly in PF-EF rats and PF-EO rats. The ratio of FBG/FINS was significant higher in PF-EO rats than in PF-SF rats. Ovarian morphology showed that the numbers of preantral follicles and atretic follicles decreased significantly, and the numbers of antral follicles and corpora lutea increased significantly in the rats of PF-EF and PF-EO.By combination of high-fat diet and testosterone injection, the obese PCOS rat model is conformable with the lifestyle habits of fatty foods and insufficient exercise, and has metabolic and reproductive characteristics of human PCOS. This model can be applied to study exercise intervention.

Asymmetric dimethylarginine (ADMA) elevation and arginase up-regulation contribute to endothelial dysfunction related to insulin resistance in rats and morbidly obese humans.

Science.gov (United States)

El Assar, Mariam; Angulo, Javier; Santos-Ruiz, Marta; Ruiz de Adana, Juan Carlos; Pindado, María Luz; Sánchez-Ferrer, Alberto; Hernández, Alberto; Rodríguez-Mañas, Leocadio

2016-06-01

The presence of insulin resistance (IR) is determinant for endothelial dysfunction associated with obesity. Although recent studies have implicated the involvement of mitochondrial superoxide and inflammation in the defective nitric oxide (NO)-mediated responses and subsequent endothelial dysfunction in IR, other mechanisms could compromise this pathway. In the present study, we assessed the role of asymmetric dimethylarginine (ADMA) and arginase with respect to IR-induced impairment of endothelium-dependent vasodilatation in human morbid obesity and in a non-obese rat model of IR. We show that both increased ADMA and up-regulated arginase are determinant factors in the alteration of the l-arginine/NO pathway associated with IR in both models and also that acute treatment of arteries with arginase inhibitor or with l-arginine significantly alleviate endothelial dysfunction. These results help to expand our knowledge regarding the mechanisms of endothelial dysfunction that are related to obesity and IR and establish potential therapeutic targets for intervention. Insulin resistance (IR) is determinant for endothelial dysfunction in human obesity. Although we have previously reported the involvement of mitochondrial superoxide and inflammation, other mechanisms could compromise NO-mediated responses in IR. We evaluated the role of the endogenous NOS inhibitor asymmetric dimethylarginine (ADMA) and arginase with respect to IR-induced impairment of l-arginine/NO-mediated vasodilatation in human morbid obesity and in a non-obese rat model of IR. Bradykinin-induced vasodilatation was evaluated in microarteries derived from insulin-resistant morbidly obese (IR-MO) and non-insulin-resistant MO (NIR-MO) subjects. Defective endothelial vasodilatation in IR-MO was improved by l-arginine supplementation. Increased levels of ADMA were detected in serum and adipose tissue from IR-MO. Serum ADMA positively correlated with IR score and negatively with pD2 for bradykinin. Gene

Asymmetric dimethylarginine (ADMA) elevation and arginase up‐regulation contribute to endothelial dysfunction related to insulin resistance in rats and morbidly obese humans

Science.gov (United States)

El Assar, Mariam; Angulo, Javier; Santos‐Ruiz, Marta; Ruiz de Adana, Juan Carlos; Pindado, María Luz; Sánchez‐Ferrer, Alberto; Hernández, Alberto

2016-01-01

Key points The presence of insulin resistance (IR) is determinant for endothelial dysfunction associated with obesity.Although recent studies have implicated the involvement of mitochondrial superoxide and inflammation in the defective nitric oxide (NO)‐mediated responses and subsequent endothelial dysfunction in IR, other mechanisms could compromise this pathway.In the present study, we assessed the role of asymmetric dimethylarginine (ADMA) and arginase with respect to IR‐induced impairment of endothelium‐dependent vasodilatation in human morbid obesity and in a non‐obese rat model of IR.We show that both increased ADMA and up‐regulated arginase are determinant factors in the alteration of the l‐arginine/NO pathway associated with IR in both models and also that acute treatment of arteries with arginase inhibitor or with l‐arginine significantly alleviate endothelial dysfunction.These results help to expand our knowledge regarding the mechanisms of endothelial dysfunction that are related to obesity and IR and establish potential therapeutic targets for intervention. Abstract Insulin resistance (IR) is determinant for endothelial dysfunction in human obesity. Although we have previously reported the involvement of mitochondrial superoxide and inflammation, other mechanisms could compromise NO‐mediated responses in IR. We evaluated the role of the endogenous NOS inhibitor asymmetric dimethylarginine (ADMA) and arginase with respect to IR‐induced impairment of l‐arginine/NO‐mediated vasodilatation in human morbid obesity and in a non‐obese rat model of IR. Bradykinin‐induced vasodilatation was evaluated in microarteries derived from insulin‐resistant morbidly obese (IR‐MO) and non‐insulin‐resistant MO (NIR‐MO) subjects. Defective endothelial vasodilatation in IR‐MO was improved by l‐arginine supplementation. Increased levels of ADMA were detected in serum and adipose tissue from IR‐MO. Serum ADMA positively correlated with

Rescue of Fructose-Induced Metabolic Syndrome by Antibiotics or Faecal Transplantation in a Rat Model of Obesity

OpenAIRE

Di Luccia, Blanda; Crescenzo, Raffaella; Mazzoli, Arianna; Cigliano, Luisa; Venditti, Paola; Walser, Jean-Claude; Widmer, Alex; Baccigalupi, Loredana; Ricca, Ezio; Iossa, Susanna

2015-01-01

A fructose-rich diet can induce metabolic syndrome, a combination of health disorders that increases the risk of diabetes and cardiovascular diseases. Diet is also known to alter the microbial composition of the gut, although it is not clear whether such alteration contributes to the development of metabolic syndrome. The aim of this work was to assess the possible link between the gut microbiota and the development of diet-induced metabolic syndrome in a rat model of obesity. Rats were fed e...

Diets containing salmon fillet delay development of high blood pressure and hyperfusion damage in kidneys in obese Zucker fa/fa rats.

Science.gov (United States)

Vikøren, Linn A; Drotningsvik, Aslaug; Mwakimonga, Angela; Leh, Sabine; Mellgren, Gunnar; Gudbrandsen, Oddrun A

2018-04-01

Hypertension is the leading risk factor for cardiovascular and chronic renal diseases, affecting more than 1 billion people. Fish intake is inversely correlated with the prevalence of hypertension in several, but not all, studies, and intake of fish oil and fish proteins has shown promising potential to delay development of high blood pressure in rats. The effects of baked and raw salmon fillet intake on blood pressure and renal function were investigated in obese Zucker fa/fa rats, which spontaneously develop hypertension with proteinuria and renal failure. Rats were fed diets containing baked or raw salmon fillet in an amount corresponding to 25% of total protein from salmon and 75% of protein from casein, or casein as the sole protein source (control group) for 4 weeks. Results show lower blood pressure and lower urine concentrations of albumin and cystatin C (relative to creatinine) in salmon diet groups when compared to control group. Morphological examinations revealed less prominent hyperfusion damage in podocytes from rats fed diets containing baked or raw salmon when compared to control rats. In conclusion, diets containing baked or raw salmon fillet delayed the development of hypertension and protected against podocyte damage in obese Zucker fa/fa rats. Copyright © 2018 American Heart Association. Published by Elsevier Inc. All rights reserved.

Proteomic Identification of Target Proteins of Thiodigalactoside in White Adipose Tissue from Diet-Induced Obese Rats

Directory of Open Access Journals (Sweden)

Hilal Ahmad Parray

2015-06-01

Full Text Available Previously, galectin-1 (GAL1 was found to be up-regulated in obesity-prone subjects, suggesting that use of a GAL1 inhibitor could be a novel therapeutic approach for treatment of obesity. We evaluated thiodigalactoside (TDG as a potent inhibitor of GAL1 and identified target proteins of TDG by performing comparative proteome analysis of white adipose tissue (WAT from control and TDG-treated rats fed a high fat diet (HFD using two dimensional gel electrophoresis (2-DE combined with MALDI-TOF-MS. Thirty-two spots from a total of 356 matched spots showed differential expression between control and TDG-treated rats, as identified by peptide mass fingerprinting. These proteins were categorized into groups such as carbohydrate metabolism, tricarboxylic acid (TCA cycle, signal transduction, cytoskeletal, and mitochondrial proteins based on functional analysis using Protein Annotation Through Evolutionary Relationship (PANTHER and Database for Annotation, Visualization, Integrated Discovery (DAVID classification. One of the most striking findings of this study was significant changes in Carbonic anhydrase 3 (CA3, Voltage-dependent anion channel 1 (VDAC1, phosphatidylethanolamine-binding protein 1 (PEBP1, annexin A2 (ANXA2 and lactate dehydrogenase A chain (LDHA protein levels between WAT from control and TDG-treated groups. In addition, we confirmed increased expression of thermogenic proteins as well as reduced expression of lipogenic proteins in response to TDG treatment. These results suggest that TDG may effectively prevent obesity, and TDG-responsive proteins can be used as novel target proteins for obesity treatment.

Food quality and motivation: a refined low-fat diet induces obesity and impairs performance on a progressive ratio schedule of instrumental lever pressing in rats.

Science.gov (United States)

Blaisdell, Aaron P; Lau, Yan Lam Matthew; Telminova, Ekatherina; Lim, Hwee Cheei; Fan, Boyang; Fast, Cynthia D; Garlick, Dennis; Pendergrass, David C

2014-04-10

Purified high-fat diet (HFD) feeding causes deleterious metabolic and cognitive effects when compared with unrefined low-fat diets in rodent models. These effects are often attributed to the diet's high content of fat, while less attention has been paid to other mechanisms associated with the diet's highly refined state. Although the effects of HFD feeding on cognition have been explored, little is known about the impact of refined vs. unrefined food on cognition. We tested the hypothesis that a refined low-fat diet (LFD) increases body weight and adversely affects cognition relative to an unrefined diet. Rats were allowed ad libitum access to unrefined rodent chow (CON, Lab Diets 5001) or a purified low-fat diet (REF, Research Diets D12450B) for 6 months, and body weight and performance on an instrumental lever pressing task were recorded. After six months on their respective diets, group REF gained significantly more weight than group CON. REF rats made significantly fewer lever presses and exhibited dramatically lower breaking points than CON rats for sucrose and water reinforcement, indicating a chronic reduction of motivation for instrumental performance. Switching the rats' diet for 9 days had no effect on these measures. Diet-induced obesity produces a substantial deficit in motivated behavior in rats, independent of dietary fat content. This holds implications for an association between obesity and motivation. Specifically, behavioral traits comorbid with obesity, such as depression and fatigue, may be effects of obesity rather than contributing causes. To the degree that refined foods contribute to obesity, as demonstrated in our study, they may play a significant contributing role to other behavioral and cognitive disorders. Copyright © 2014 Elsevier Inc. All rights reserved.

Intraventricular Injection of LKB1 Inhibits the Formation of Diet-Induced Obesity in Rats by Activating the AMPK-POMC Neurons-Sympathetic Nervous System Axis

Directory of Open Access Journals (Sweden)

Pengjiao Xi

2018-05-01

Full Text Available Background/Aims: Obesity is increasingly becoming a major public health problem worldwide. Peripheral LKB1 inhibits white fat generation, but the effect of central LKB1 on diet-induced obesity (DIO is unknown. Therefore, we examined whether LKB1 over-expression in the hypothalamus can inhibit the development of obesity. Methods: Adult male Sprague-Dawley rats were anesthetized and placed in a stereotaxic apparatus. LKB1-AAV-EGFP (2.0 × 108 or 2.0 × 1010 vector genomes or Control-AAV-EGFP (2.0 × 108 vector genomes was injected into the third ventricle. After administration, the rats were fed a high-fat diet (HFD for 9 weeks to induce obesity. Rats fed a chow fat diet were used as normal controls. Results: LKB1 delivery decreased body weight, energy intake, fat mass, and serum lipid levels. LKB1 also improved HFD-induced hepatic fatty degeneration. Interestingly, LKB1 over-expression in the hypothalamus activated the AMPK-POMC neurons-sympathetic nervous system (SNS axis, which can release epinephrine to promote white fat browning. Conversely, the elevated expression of MC3R/MC4R inhibited food intake. These two factors worked together to inhibit the development of obesity. Conclusions: LKB1 in the hypothalamus may have therapeutic potential for DIO through the activation of the AMPK-POMC neurons-SNS axis.

Intraventricular Injection of LKB1 Inhibits the Formation of Diet-Induced Obesity in Rats by Activating the AMPK-POMC Neurons-Sympathetic Nervous System Axis.

Science.gov (United States)

Xi, Pengjiao; Du, Jianying; Liang, Huimin; Han, Jie; Wu, Zhaoxia; Wang, Haomin; He, Lu; Wang, Qiming; Ge, Haize; Li, Yongmei; Xue, Jie; Tian, Derun

2018-01-01

Obesity is increasingly becoming a major public health problem worldwide. Peripheral LKB1 inhibits white fat generation, but the effect of central LKB1 on diet-induced obesity (DIO) is unknown. Therefore, we examined whether LKB1 over-expression in the hypothalamus can inhibit the development of obesity. Adult male Sprague-Dawley rats were anesthetized and placed in a stereotaxic apparatus. LKB1-AAV-EGFP (2.0 × 108 or 2.0 × 1010 vector genomes) or Control-AAV-EGFP (2.0 × 108 vector genomes) was injected into the third ventricle. After administration, the rats were fed a high-fat diet (HFD) for 9 weeks to induce obesity. Rats fed a chow fat diet were used as normal controls. LKB1 delivery decreased body weight, energy intake, fat mass, and serum lipid levels. LKB1 also improved HFD-induced hepatic fatty degeneration. Interestingly, LKB1 over-expression in the hypothalamus activated the AMPK-POMC neurons-sympathetic nervous system (SNS) axis, which can release epinephrine to promote white fat browning. Conversely, the elevated expression of MC3R/MC4R inhibited food intake. These two factors worked together to inhibit the development of obesity. LKB1 in the hypothalamus may have therapeutic potential for DIO through the activation of the AMPK-POMC neurons-SNS axis. © 2018 The Author(s). Published by S. Karger AG, Basel.

The PPARα/γ Agonist, Tesaglitazar, Improves Insulin Mediated Switching of Tissue Glucose and Free Fatty Acid Utilization In Vivo in the Obese Zucker Rat

Directory of Open Access Journals (Sweden)

Kristina Wallenius

2013-01-01

Full Text Available Metabolic flexibility was assessed in male Zucker rats: lean controls, obese controls, and obese rats treated with the dual peroxisome proliferator activated receptor (PPAR agonist, tesaglitazar, 3 μmol/kg/day for 3 weeks. Whole body glucose disposal rate ( and hepatic glucose output (HGO were assessed under basal fasting and hyperinsulinemic isoglycemic clamp conditions using [3,3H]glucose. Indices of tissue specific glucose utilization ( were measured at basal, physiological, and supraphysiological levels of insulinemia using 2-deoxy-D-[2,6-3H]glucose. Finally, whole body and tissue specific FFA and glucose utilization and metabolic fate were evaluated under basal and hyperinsulinemic conditions using a combination of [U-13C]glucose, 2-deoxy-D-[U-14C]glucose, [U-14C]palmitate, and [9,10-3H]-(R-bromopalmitate. Tesaglitazar improved whole body insulin action by greater suppression of HGO and stimulation of compared to obese controls. This involved increased insulin stimulation of in fat and skeletal muscle as well as increased glycogen synthesis. Tesaglitazar dramatically improved insulin mediated suppression of plasma FFA level, whole body turnover (, and muscle, liver, and fat utilization. At basal insulin levels, tesaglitazar failed to lower HGO or compared to obese controls. In conclusion, the results demonstrate that tesaglitazar has a remarkable ability to improve insulin mediated control of glucose and FFA fluxes in obese Zucker rats.

An electronic health record-enabled obesity database

Directory of Open Access Journals (Sweden)

Wood G

2012-05-01

Full Text Available Abstract Background The effectiveness of weight loss therapies is commonly measured using body mass index and other obesity-related variables. Although these data are often stored in electronic health records (EHRs and potentially very accessible, few studies on obesity and weight loss have used data derived from EHRs. We developed processes for obtaining data from the EHR in order to construct a database on patients undergoing Roux-en-Y gastric bypass (RYGB surgery. Methods Clinical data obtained as part of standard of care in a bariatric surgery program at an integrated health delivery system were extracted from the EHR and deposited into a data warehouse. Data files were extracted, cleaned, and stored in research datasets. To illustrate the utility of the data, Kaplan-Meier analysis was used to estimate length of post-operative follow-up. Results Demographic, laboratory, medication, co-morbidity, and survey data were obtained from 2028 patients who had undergone RYGB at the same institution since 2004. Pre-and post-operative diagnostic and prescribing information were available on all patients, while survey laboratory data were available on a majority of patients. The number of patients with post-operative laboratory test results varied by test. Based on Kaplan-Meier estimates, over 74% of patients had post-operative weight data available at 4 years. Conclusion A variety of EHR-derived data related to obesity can be efficiently obtained and used to study important outcomes following RYGB.

Analysis of time-dependent adaptations in whole-body energy balance in obesity induced by high-fat diet in rats

Directory of Open Access Journals (Sweden)

Maghdoori Babak

2011-06-01

Full Text Available Abstract Background High-fat (HF diet has been extensively used as a model to study metabolic disorders of human obesity in rodents. However, the adaptive whole-body metabolic responses that drive the development of obesity with chronically feeding a HF diet are not fully understood. Therefore, this study investigated the physiological mechanisms by which whole-body energy balance and substrate partitioning are adjusted in the course of HF diet-induced obesity. Methods Male Wistar rats were fed ad libitum either a standard or a HF diet for 8 weeks. Food intake (FI and body weight were monitored daily, while oxygen consumption, respiratory exchange ratio, physical activity, and energy expenditure (EE were assessed weekly. At week 8, fat mass and lean body mass (LBM, fatty acid oxidation and uncoupling protein-1 (UCP-1 content in brown adipose tissue (BAT, as well as acetyl-CoA carboxylase (ACC content in liver and epidydimal fat were measured. Results Within 1 week of ad libitum HF diet, rats were able to spontaneously reduce FI to precisely match energy intake of control rats, indicating that alterations in dietary energy density were rapidly detected and FI was self-regulated accordingly. Oxygen consumption was higher in HF than controls throughout the study as whole-body fat oxidation also progressively increased. In HF rats, EE initially increased, but then reduced as dark cycle ambulatory activity reached values ~38% lower than controls. No differences in LBM were detected; however, epidydimal, inguinal, and retroperitoneal fat pads were 1.85-, 1.89-, and 2.54-fold larger in HF-fed than control rats, respectively. Plasma leptin was higher in HF rats than controls throughout the study, indicating the induction of leptin resistance by HF diet. At week 8, UCP-1 content and palmitate oxidation in BAT were 3.1- and 1.5-fold higher in HF rats than controls, respectively, while ACC content in liver and epididymal fat was markedly reduced

SGLT2-inhibitor and DPP-4 inhibitor improve brain function via attenuating mitochondrial dysfunction, insulin resistance, inflammation, and apoptosis in HFD-induced obese rats.

Science.gov (United States)

Sa-Nguanmoo, Piangkwan; Tanajak, Pongpan; Kerdphoo, Sasiwan; Jaiwongkam, Thidarat; Pratchayasakul, Wasana; Chattipakorn, Nipon; Chattipakorn, Siriporn C

2017-10-15

Dipeptidyl peptidase-4 inhibitor (vildagliptin) has been shown to exert beneficial effects on insulin sensitivity and neuroprotection in obese-insulin resistance. Recent studies demonstrated the neuroprotection of the sodium-glucose co-transporter 2 inhibitor (dapagliflozin) in diabetes. However, the comparative effects of both drugs and a combination of two drugs on metabolic dysfunction and brain dysfunction impaired by the obese-insulin resistance have never been investigated. Forty male Wistar rats were divided into two groups, and received either a normal-diet (ND, n=8) or a high-fat diet (HFD, n=32) for 16weeks. At week 13, the HFD-fed rats were divided into four subgroups (n=8/subgroup) to receive either a vehicle, vildagliptin (3mg/kg/day) dapagliflozin (1mg/kg/day) or combined drugs for four weeks. ND rats were given a vehicle for four weeks. Metabolic parameters and brain function were investigated. The results demonstrated that HFD rats developed obese-insulin resistance and cognitive decline. Dapagliflozin had greater efficacy on improved peripheral insulin sensitivity and reduced weight gain than vildagliptin. Single therapy resulted in equally improved brain mitochondrial function, insulin signaling, apoptosis and prevented cognitive decline. However, only dapagliflozin improved hippocampal synaptic plasticity. A combination of the drugs had greater efficacy in improving brain insulin sensitivity and reducing brain oxidative stress than the single drug therapy. These findings suggested that dapagliflozin and vildagliptin equally prevented cognitive decline in the obese-insulin resistance, possibly through some similar mechanisms. Dapagliflozin had greater efficacy than vildagliptin for preserving synaptic plasticity, thus combined drugs could be the best therapeutic approach for neuroprotection in the obese-insulin resistance. Copyright © 2017 Elsevier Inc. All rights reserved.

A High-Protein Diet Reduces Weight Gain, Decreases Food Intake, Decreases Liver Fat Deposition, and Improves Markers of Muscle Metabolism in Obese Zucker Rats

Directory of Open Access Journals (Sweden)

William W. French

2017-06-01

Full Text Available A primary factor in controlling and preventing obesity is through dietary manipulation. Diets higher in protein have been shown to improve body composition and metabolic health during weight loss. The objective of this study was to examine the effects of a high-protein diet versus a moderate-protein diet on muscle, liver and fat metabolism and glucose regulation using the obese Zucker rat. Twelve-week old, male, Zucker (fa/fa and lean control (Fa/fa rats were randomly assigned to either a high-protein (40% energy or moderate-protein (20% energy diet for 12 weeks, with a total of four groups: lean 20% protein (L20; n = 8, lean 40% protein (L40; n = 10, obese 20% protein (O20; n = 8, and obese 40% protein (O40; n = 10. At the end of 12 weeks, animals were fasted and euthanized. There was no difference in food intake between L20 and L40. O40 rats gained less weight and had lower food intake (p < 0.05 compared to O20. O40 rats had lower liver weight (p < 0.05 compared to O20. However, O40 rats had higher orexin (p < 0.05 levels compared to L20, L40 and O20. Rats in the L40 and O40 groups had less liver and muscle lipid deposition compared to L20 and L40 diet rats, respectively. O40 had decreased skeletal muscle mechanistic target of rapamycin complex 1 (mTORC1 phosphorylation and peroxisome proliferator-activated receptor gamma (PPARγ mRNA expression compared to O20 (p < 0.05, with no difference in 5′ AMP-activated protein kinase (AMPK, eukaryotic translation initiation factor 4E binding protein 1 (4EBP1, protein kinase B (Akt or p70 ribosomal S6 kinase (p70S6K phosphorylation. The data suggest that high-protein diets have the potential to reduce weight gain and alter metabolism, possibly through regulation of an mTORC1-dependent pathway in skeletal muscle.

Social jet-lag potentiates obesity and metabolic syndrome when combined with cafeteria diet in rats.

Science.gov (United States)

Espitia-Bautista, Estefania; Velasco-Ramos, Mario; Osnaya-Ramírez, Iván; Ángeles-Castellanos, Manuel; Buijs, Ruud M; Escobar, Carolina

2017-07-01

Modern lifestyle promotes shifted sleep onset and shifted wake up time between weekdays and weekends, producing a condition termed "social-jet lag." Disrupted sleep promotes increased appetite for carbohydrate and fat-rich food, which in long term leads to overweight, obesity and metabolic syndrome. In order to mimic the human situation we produced an experimental model of social-jet lag (Sj-l). With this model, we explored the link between shifted sleep time with consumption of a cafeteria diet (CafD) and the development of obesity and metabolic syndrome. The first experiment was designed to create and confirm the model of Sj-l. Rats (n=8-10/group) were exposed to a shifted sleep time protocol achieved by placing the rats in slow rotating wheels from Monday to Friday during the first 4h of the light period, while on weekends they were left undisturbed. The second experiment (n=8-12/group) explored the combined effect of Sj-l with the opportunity to ingest CafD. All protocols lasted 12weeks. We evaluated the development of overweight and indicators of metabolic syndrome. The statistical significance for all variables was set at Pdislipidemia. Present data provide an experimental model of social-jet lag that combined with overconsumption of CafD, and maximized the development of obesity and metabolic syndrome. Importantly, access to CafD during the night did not lead to overweight nor metabolic syndrome. Copyright © 2017 Elsevier Inc. All rights reserved.

Dipeptidyl peptidase 4 inhibitor attenuates obesity-induced myocardial fibrosis by inhibiting transforming growth factor-βl and Smad2/3 pathways in high-fat diet-induced obesity rat model.

Science.gov (United States)

Hong, Seul-Ki; Choo, Eun-Ho; Ihm, Sang-Hyun; Chang, Kiyuk; Seung, Ki-Bae

2017-11-01

Obesity-induced myocardial fibrosis may lead to diastolic dysfunction and ultimately heart failure. Activation of the transforming growth factor (TGF)-βl and its downstream Smad2/3 pathways may play a pivotal role in the pathogenesis of obesity-induced myocardial fibrosis, and the antidiabetic dipeptidyl peptidase 4 inhibitors (DPP4i) might affect these pathways. We investigated whether DPP4i reduces myocardial fibrosis by inhibiting the TGF-β1 and Smad2/3 pathways in the myocardium of a diet-induced obesity (DIO) rat model. Eight-week-old male spontaneously hypertensive rats (SHRs) were fed either a normal fat diet (chow) or a high-fat diet (HFD) and then the HFD-fed SHRs were randomized to either the DPP4i (MK-0626) or control (distilled water) groups for 12weeks. At 20weeks old, all the rats underwent hemodynamic and metabolic studies and Doppler echocardiography. Compared with the normal fat diet (chow)-fed SHRs, the HFD-fed SHRs developed a more intense degree of hyperglycemia and dyslipidemia and showed a constellation of left ventricular (LV) diastolic dysfunction, and exacerbated myocardial fibrosis, as well as activation of the TGF-β1 and Smad2/3 pathways. DPP4i significantly improved the metabolic and hemodynamic parameters. The echocardiogram showed that DPP4i improved the LV diastolic dysfunction (early to late ventricular filling velocity [E/A] ratio, 1.49±0.21 vs. 1.77±0.09, p<0.05). Furthermore, DPP4i significantly reduced myocardial fibrosis and collagen production by the myocardium and suppressed TGF-β1 and phosphorylation of Smad2/3 in the heart. In addition, DPP4i decreased TGF-β1-induced collagen production and TGF-β1-mediated phosphorylation and nuclear translocation of Smad2/3 in rat cardiac fibroblasts. In conclusion, DPP4 inhibition attenuated myocardial fibrosis and improved LV diastolic dysfunction in a DIO rat model by modulating the TGF-β1 and Smad2/3 pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

[The effect of N-stearoylethanolamine on liver phospholipid composition of rats with insulin resistance caused by alimentary obesity].

Science.gov (United States)

Onopchenko, O V; Kosiakova, H V; Horid'ko, T M; Klimashevskyĭ, V M; Hula, N M

2014-01-01

We used alimentary obesity-induced insulin resistance (IR) model in rats to investigate the influence of N-stearoylethanolamine on the content of phospholipids and their fatty acid composition. Our results show that prolonged high-fat diet triggers considerable aberrations in the composition of main phospholipids in the liver and can be one of the causes of IR in rats. In particular, the increase of phosphatidylcholine, phosphatidylethanolamine and significant decrease of other phospholipids: lysophosphatidylcholine, lysophosphatidylethanolamine, sphingomyelin, phosphatidylinositol, phosphatidylserine and diphosphaglicerol were observed. The levels of monounsaturated (erucic, nervonic, oleic) and polyunsaturated (eicosatrienoic, docosatrienoic, arachidonic) fatty acids were increased; meanwhile the content of diunsaturated acids was decreased. The NSE administration (50 mg/kg of body weight) caused restoration of the phospholipids content in the liver of rats with diet-induced IR that highly correlated with the decrease in plasma insulin level and the improvement of insulin sensitivity. Moreover, the effect of NSE was accompanied by the normalization of fatty acids composition of phospholipids that could be related to modulating influence of NSE on the activity of the main fatty acid desaturases. It is known that the imbalance in phospholipid composition of the rat liver causes substantial metabolic alterations that are associated with the development of IR. Accordingly, the compensations of the imbalance by NSE can help to restore insulin sensitivity, inhibit the development of obesity, IR and type 2 diabetes.

Prebiotic Fibre Supplementation In Combination With Metformin Modifies Appetite, Energy Metabolism, And Gut Satiety Hormones In Obese Rats

Science.gov (United States)

Pyra, Kim Alicia

The prebiotic fibre, oligofructose (OFS), reduces energy intake and improves glycemic control in rodents and man. Metformin (MT) is a commonly used insulin-sensitizing agent that may limit weight gain in individuals with type 2 diabetes. Our objective was to determine if using OFS as an adjunct to MT therapy (AD) modifies satiety hormone production and metabolism in obese rats. Independently, OFS and MT decreased energy intake, body fat, hepatic triglyceride content, plasma leptin and glucose-dependent insulinotropic peptide (GIP) levels. OFS and AD but not MT rats showed superior glycemic control during an oral glucose tolerance test (OGTT) compared to C. Area under the curve for GIP was lowest in ADThe prebiotic fibre, oligofructose (OFS), reduces energy intake and improves glycemic control in rodents and man. Metformin (MT) is a commonly used insulin-sensitizing agent that may limit weight gain in individuals with type 2 diabetes. Our objective was to determine if using OFS as an adjunct to MT therapy (AD) modifies satiety hormone production and metabolism in obese rats. Independently, OFS and MT decreased energy intake, body fat, hepatic triglyceride content, plasma leptin and glucose-dependent insulinotropic peptide (GIP) levels. OFS and AD but not MT rats showed superior glycemic control during an oral glucose tolerance test (OGTT) compared to C. Area under the curve for GIP was lowest in AD

Dietary effect of pomegranate seed oil rich in 9cis, 11trans, 13cis conjugated linolenic acid on lipid metabolism in obese, hyperlipidemic OLETF Rats

Directory of Open Access Journals (Sweden)

Cha Jae-Young

2004-11-01

Full Text Available Abstract Conjugated fatty acid, the general term of positional and geometric isomers of polyunsaturated fatty acids with conjugated double bonds, has attracted considerable attention because of its potentially beneficial biological effects. In the present study, dietary effect of pomegranate seed oil rich in punicic acid (9cis, 11trans, 13cis-conjugated linolenic acid; 9c, 11t, 13c-CLNA on lipid metabolism was investigated in obese, hyperlipidemic Otsuka Long-Evans Tokushima Fatty (OLETF rats. After 2 weeks feeding period, OLETF rats revealed obesity and hyperlipidemia compared with their progenitor LETO rats. Feeding of the diet supplemented with 9% safflower oil and 1% pomegranate seed oil (9c, 11t, 13c-CLNA diet did not affect abdominal white adipose tissue weights and serum lipid levels compared with the diet supplemented with 10% safflower oil (control diet in OLETF rats. However, the accumulated hepatic triacylglycerol was markedly decreased by 9c, 11t, 13c-CLNA diet in OLETF rats. Activities of hepatic enzymes related to fatty acid synthesis and fatty acid β-oxidation were not altered by 9c, 11t, 13c-CLNA diet. Levels of monounsaturated fatty acid (MUFA, major storage form of fatty acid, in serum triacylglycerol were markedly higher in obese, hyperlipidemic OLETF rats than in lean LETO rats. In addition, 9c, 11t, 13c-CLNA diet significantly decreased MUFA levels in OLETF rats. This is the first study showing that 9c, 11t, 13c-CLNA suppresses delta-9 desaturation in vivo, and we suggest that the alleviation of hepatic triacylglycerol accumulation by 9c, 11t, 13c-CLNA diet was, at least in part, attributable to the suppression of delta-9 desaturation in OLETF rats.

Multi-Institutional Sharing of Electronic Health Record Data to Assess Childhood Obesity.

Directory of Open Access Journals (Sweden)

L Charles Bailey

Full Text Available To evaluate the validity of multi-institutional electronic health record (EHR data sharing for surveillance and study of childhood obesity.We conducted a non-concurrent cohort study of 528,340 children with outpatient visits to six pediatric academic medical centers during 2007-08, with sufficient data in the EHR for body mass index (BMI assessment. EHR data were compared with data from the 2007-08 National Health and Nutrition Examination Survey (NHANES.Among children 2-17 years, BMI was evaluable for 1,398,655 visits (56%. The EHR dataset contained over 6,000 BMI measurements per month of age up to 16 years, yielding precise estimates of BMI. In the EHR dataset, 18% of children were obese versus 18% in NHANES, while 35% were obese or overweight versus 34% in NHANES. BMI for an individual was highly reliable over time (intraclass correlation coefficient 0.90 for obese children and 0.97 for all children. Only 14% of visits with measured obesity (BMI ≥95% had a diagnosis of obesity recorded, and only 20% of children with measured obesity had the diagnosis documented during the study period. Obese children had higher primary care (4.8 versus 4.0 visits, p<0.001 and specialty care (3.7 versus 2.7 visits, p<0.001 utilization than non-obese counterparts, and higher prevalence of diverse co-morbidities. The cohort size in the EHR dataset permitted detection of associations with rare diagnoses. Data sharing did not require investment of extensive institutional resources, yet yielded high data quality.Multi-institutional EHR data sharing is a promising, feasible, and valid approach for population health surveillance. It provides a valuable complement to more resource-intensive national surveys, particularly for iterative surveillance and quality improvement. Low rates of obesity diagnosis present a significant obstacle to surveillance and quality improvement for care of children with obesity.

Gender-Associated Impact of Early Leucine Supplementation on Adult Predisposition to Obesity in Rats

Directory of Open Access Journals (Sweden)

Nora López

2018-01-01

Full Text Available Early nutrition plays an important role in development and may constitute a relevant contributor to the onset of obesity in adulthood. The aim of this study was to evaluate the long-term impact of maternal leucine (Leu supplementation during lactation on progeny in rats. A chow diet, supplemented with 2% Leu, was supplied during lactation (21 days and, from weaning onwards, was replaced by a standard chow diet. Then, at adulthood (6 months of age, this was replaced with hypercaloric diets (either with high-fat (HF or high-carbohydrate (HC content, for two months, to induce obesity. Female offspring from Leu-supplemented dams showed higher increases in body weight and in body fat (62% than their respective controls; whereas males were somehow protected (15% less fat than the corresponding controls. This profile in Leu-females was associated with altered neuronal architecture at the paraventricular nucleus (PVN, involving neuropeptide Y (NPY fibers and impaired expression of neuropeptides and factors of the mTOR signaling pathway in the hypothalamus. Interestingly, leptin and adiponectin expression in adipose tissue at weaning and at the time before the onset of obesity could be defined as early biomarkers of metabolic disturbance, predisposing towards adult obesity under the appropriate environment.

Gender-Associated Impact of Early Leucine Supplementation on Adult Predisposition to Obesity in Rats

Science.gov (United States)

López, Nora; Sánchez, Juana; Palou, Andreu; Serra, Francisca

2018-01-01

Early nutrition plays an important role in development and may constitute a relevant contributor to the onset of obesity in adulthood. The aim of this study was to evaluate the long-term impact of maternal leucine (Leu) supplementation during lactation on progeny in rats. A chow diet, supplemented with 2% Leu, was supplied during lactation (21 days) and, from weaning onwards, was replaced by a standard chow diet. Then, at adulthood (6 months of age), this was replaced with hypercaloric diets (either with high-fat (HF) or high-carbohydrate (HC) content), for two months, to induce obesity. Female offspring from Leu-supplemented dams showed higher increases in body weight and in body fat (62%) than their respective controls; whereas males were somehow protected (15% less fat than the corresponding controls). This profile in Leu-females was associated with altered neuronal architecture at the paraventricular nucleus (PVN), involving neuropeptide Y (NPY) fibers and impaired expression of neuropeptides and factors of the mTOR signaling pathway in the hypothalamus. Interestingly, leptin and adiponectin expression in adipose tissue at weaning and at the time before the onset of obesity could be defined as early biomarkers of metabolic disturbance, predisposing towards adult obesity under the appropriate environment. PMID:29329236

Electron-microscopic autoradiography of tritiated testosterone in rat testis

International Nuclear Information System (INIS)

Frederik, P.M.; Molen, H.J. van der; Galjaard, H.; Klepper, D.

1977-01-01

The feasibility of a technique for autoradiography of diffusible substances has been further tested by analysing the localization of steroids in rats testes with the light- and electron-microscope. Testes of rats were perfused with tritiated testosterone (3 min) followed by 15-min perfusion with buffer containing a 100-fold excess of unlabelled testosterone. Tissue samples were frozen, freeze dried, fixed in osmium vapour and embedded in Epon. To exclude extraction of steroids, contact with water and other solvents was prevented during cutting of thin sections on an ultracryotome and further treatment for autoradiography. Light- and electron-microscopic observations indicated that the highest concentration of labelled testosterone was present within the basal parts of the Sertoli cell cytoplasm and in lipid inclusions of Sertoli cells within the seminiferous tubules. This is the first account of autoradiography of steroids at the electron-microscope level. (author)

A High-Protein Diet Reduces Weight Gain, Decreases Food Intake, Decreases Liver Fat Deposition, and Improves Markers of Muscle Metabolism in Obese Zucker Rats.

Science.gov (United States)

French, William W; Dridi, Sami; Shouse, Stephanie A; Wu, Hexirui; Hawley, Aubree; Lee, Sun-Ok; Gu, Xuan; Baum, Jamie I

2017-06-08

A primary factor in controlling and preventing obesity is through dietary manipulation. Diets higher in protein have been shown to improve body composition and metabolic health during weight loss. The objective of this study was to examine the effects of a high-protein diet versus a moderate-protein diet on muscle, liver and fat metabolism and glucose regulation using the obese Zucker rat. Twelve-week old, male, Zucker (fa/fa) and lean control (Fa/fa) rats were randomly assigned to either a high-protein (40% energy) or moderate-protein (20% energy) diet for 12 weeks, with a total of four groups: lean 20% protein (L20; n = 8), lean 40% protein (L40; n = 10), obese 20% protein (O20; n = 8), and obese 40% protein (O40; n = 10). At the end of 12 weeks, animals were fasted and euthanized. There was no difference in food intake between L20 and L40. O40 rats gained less weight and had lower food intake ( p diet rats, respectively. O40 had decreased skeletal muscle mechanistic target of rapamycin complex 1 (mTORC1) phosphorylation and peroxisome proliferator-activated receptor gamma (PPARγ) mRNA expression compared to O20 ( p protein kinase (AMPK), eukaryotic translation initiation factor 4E binding protein 1 (4EBP1), protein kinase B (Akt) or p70 ribosomal S6 kinase (p70S6K) phosphorylation. The data suggest that high-protein diets have the potential to reduce weight gain and alter metabolism, possibly through regulation of an mTORC1-dependent pathway in skeletal muscle.

Effect of exercise and obesity on skeletal muscle amino acid uptake

International Nuclear Information System (INIS)

Friedman, J.E.

1988-01-01

To determine if amino acid uptake by muscle of the obese Zucker rat is impaired, epitrochlearis (EPI) and soleus strip (SOL) muscles from 32 pairs of female lean (Fa/-) and obese (fa/fa) Zucker rats were incubated using [ 14 C]α-aminoisobutyric acid (AIB). Because contractile activity also influences amino acid uptake, the effect of acute endurance exercise on amino acid uptake by skeletal muscle from lean and obese rats was also studied. Muscle wet and dry weights were similar in lean and obese rats. However, both muscle protein content and concentration from obese rats were significantly reduced. In preliminary studies, pinning EPI at resting length during incubation significantly increased AIB uptake and reduced muscle water accumulation. AIB uptake was similar in stripped and intact SOL. Lean and obese rats were studied at rest or following a 1 hr treadmill run at 8% grade Muscles were pinned, and preincubated for 30 min at 37 degree C in Krebs Ringer bicarbonate buffer (KRB) containing 5mM glucose under 95:5 O 2 /CO 2 , followed by 30, 60, 120, or 180 min of incubation in KRB with 0.5 mM AIB, [ 14 C]-AIB to measure amino acid, and [ 3 H]-inulin to determine extracellular water

Downregulation of transient receptor potential M6 channels as a cause of hypermagnesiuric hypomagnesemia in obese type 2 diabetic rats.

Science.gov (United States)

Takayanagi, Kaori; Shimizu, Taisuke; Tayama, Yosuke; Ikari, Akira; Anzai, Naohiko; Iwashita, Takatsugu; Asakura, Juko; Hayashi, Keitaro; Mitarai, Tetsuya; Hasegawa, Hajime

2015-06-15

We assessed the expression profile of Mg(2+)-transporting molecules in obese diabetic rats as a cause of hypermagnesiuric hypomagnesemia, which is involved in the development of insulin resistance, hypertension, and coronary diseases. Kidneys were obtained from male Otsuka Long-Evans Tokushima fatty (OLETF) and Long-Evans Tokushima Otsuka (LETO) obese diabetic rats at the ages of 16, 24, and 34 wk. Expression profiles were studied by real-time PCR and immunohistochemistry together with measurements of urine Mg(2+) excretion. Urine Mg(2+) excretion was increased in 24-wk-old OLETF rats and hypomagnesemia was apparent in 34-wk-old OLETF rats but not in LETO rats (urine Mg(2+) excretion: 0.16 ± 0.01 μg·min(-1)·g body wt(-1) in 24-wk-old LETO rats and 0.28 ± 0.01 μg·min(-1)·g body wt(-1) in 24-wk-old OLETF rats). Gene expression of transient receptor potential (TRP)M6 was downregulated (85.5 ± 5.6% in 34-wk-old LETO rats and 63.0 ± 3.5% in 34-wk-old OLETF rats) concomitant with Na(+)-Cl(-) cotransporter downregulation, whereas the expression of claudin-16 in tight junctions of the thick ascending limb of Henle was not different. The results of the semiquantitative analysis of immunohistochemistry were consistent with these findings (TRPM6: 0.49 ± 0.04% in 16-wk-old LETO rats, 0.10 ± 0.01% in 16-wk-old OLETF rats, 0.52 ± 0.03% in 24-wk-old LETO rats, 0.10 ± 0.01% in 24-wk-old OLETF rats, 0.48 ± 0.02% in 34-wk-old LETO rats, and 0.12 ± 0.02% in 34-wk-old OLETF rats). Gene expression of fibrosis-related proinflammatory cytokines as well as histological changes showed that the hypermagnesiuria-related molecular changes and tubulointerstitial nephropathy developed independently. TRPM6, located principally in distal convoluted tubules, appears to be a susceptible molecule that causes hypermagnesiuric hypomagnesemia as a tubulointerstitial nephropathy-independent altered tubular function in diabetic nephropathy. Copyright © 2015 the American Physiological

The effect of N-stearoylethanolamine on liver phospholipid composition of rats with insulin resistance caused by alimentary obesity

Directory of Open Access Journals (Sweden)

O. V. Onopchenko

2014-02-01

Full Text Available We used alimentary obesity-induced insulin resistance (IR model in rats to investigate the influence of N-stearoylethanolamine on the content of phospholipids and their fatty acid composition. Our results show that prolonged high-fat diet triggers considerable aberrations in the composition of main phospholipids in the liver and can be one of the causes of IR in rats. In particular, the increase of phosphatidylcholine, phosphatidylethanolamine and significant decrease of other phospholipids: lysophosphatidylcholine, lysophosphatidylethanolamine, sphingomyelin, phosphatidylinositol, phosphatidylserine and diphosphaglicerol were observed. The levels of monounsaturated (erucic, nervonic, oleic and polyunsaturated (eicosatrienoic, docosatrienoic, arachidonic fatty acids were increased; meanwhile the content of diunsaturated acids was decreased. The NSE administration (50 mg/kg of body weight caused restoration of the phospholipids content in the liver of rats with diet-induced IR that highly correlated with the decrease in plasma insulin level and the improvement of insulin sensitivity. Moreover, the effect of NSE was accompanied by the normalization of fatty acids composition of phospholipids that could be related to modulating influen­ce of NSE on the activity of the main fatty acid desaturases. It is known that the imbalance in phospholipid composition of the rat liver causes substantial metabolic alterations that are associated with the development of IR. Accordingly, the compensations of the imbalance by NSE can help to restore insulin sensitivity, inhibit the development of obesity, IR and type 2 diabetes.

High-resolution magnetic resonance imaging tracks changes in organ and tissue mass in obese and aging rats.

Science.gov (United States)

Tang, Haiying; Vasselli, Joseph R; Wu, Ed X; Boozer, Carol N; Gallagher, Dympna

2002-03-01

Magnetic resonance imaging (MRI) has the ability to discriminate between various soft tissues in vivo. Whole body, specific organ, total adipose tissue (TAT), intra-abdominal adipose tissue (IAAT), and skeletal muscle (SM) weights determined by MRI were compared with weights determined by dissection and chemical analysis in two studies with male Sprague-Dawley rats. A 4.2-T MRI machine acquired high-resolution, in vivo, longitudinal whole body images of rats as they developed obesity or aged. Weights of the whole body and specific tissues were determined using computer image analysis software, including semiautomatic segmentation algorithms for volume calculations. High correlations were found for body weight (r = 0.98), TAT (r = 0.99), and IAAT (r = 0.98) between MRI and dissection and chemical analyses. MRI estimated the weight of the brain, kidneys, and spleen with high accuracy (r > 0.9), but overestimated IAAT, SM, and liver volumes. No differences were detected in organ weights using MRI and dissection measurements. Longitudinal MRI measurements made during the development of obesity and aging accurately represented changes in organ and tissue mass.

Increased cardiovascular reactivity to acute stress and salt-loading in adult male offspring of fat fed non-obese rats.

Directory of Open Access Journals (Sweden)

Olena Rudyk

Full Text Available Diet-induced obesity in rat pregnancy has been shown previously to be associated with consistently raised blood pressure in the offspring, attributed to sympathetic over-activation, but the relative contributions to this phenotype of maternal obesity versus raised dietary fat is unknown. Sprague-Dawley female rats were fed either a control (4.3% fat, n = 11 or lard-enriched (23.6% fat, n = 16 chow 10 days prior to mating, throughout pregnancy and lactation. In conscious adult (9-month-old offspring cardiovascular parameters were measured (radiotelemetry. The short period of fat-feeding did not increase maternal weight versus controls and the baseline blood pressure was similar in offspring of fat fed dams (OF and controls (OC. However, adult male OF showed heightened cardiovascular reactivity to acute restraint stress (p<0.01; Δ systolic blood pressure (SBP and Δheart rate (HR with a prolonged recovery time compared to male OC. α1/β-adrenergic receptor blockade normalised the response. Also, after dietary salt-loading (8%-NaCl ad libitum for 1 week male OF demonstrated higher SBP (p<0.05 in the awake phase (night-time and increased low/high frequency ratio of power spectral density of HR variability versus OC. Baroreflex gain and basal power spectral density components of the heart rate or blood pressure were similar in male OF and OC. Minor abnormalities were evident in female OF. Fat feeding in the absence of maternal obesity in pregnant rats leads to altered sympathetic control of cardiovascular function in adult male offspring, and hypertension in response to stressor stimuli.

High intake of palatable food predicts binge-eating independent of susceptibility to obesity: an animal model of lean vs obese binge-eating and obesity with and without binge-eating.

Science.gov (United States)

Boggiano, M M; Artiga, A I; Pritchett, C E; Chandler-Laney, P C; Smith, M L; Eldridge, A J

2007-09-01

To determine the stability of individual differences in non-nutritive 'junk' palatable food (PF) intake in rats; assess the relationship of these differences to binge-eating characteristics and susceptibility to obesity; and evaluate the practicality of using these differences to model binge-eating and obesity. Binge-eating prone (BEP) and resistant (BER) groups were identified. Differential responses to stress, hunger, macronutrient-varied PFs, a diet-induced obesity (DIO) regimen and daily vs intermittent access to a PF+chow diet, were assessed. One hundred and twenty female Sprague-Dawley rats. Reliability of intake patterns within rats; food intake and body weight after various challenges over acute (1, 2, 4 h), 24-h and 2-week periods. Although BEP and BER rats did not differ in amount of chow consumed, BEPs consumed >50% more intermittent PF than BERs (PBEPs suppressed chow but not PF intake when stressed, and ate as much when sated as when hungry. Conversely, BERs were more affected by stress and ate less PF, not chow, when stressed and were normally hyperphagic to energy deficit. BEP overeating generalized to other PFs varying in sucrose, fat and nutrition content. Half the rats in each group proved to be obesity prone after a no-choice high fat diet (DIO diet) but a continuous diet of PF+chow normalized the BEPs high drive for PF. Greater intermittent intake of PF predicts binge-eating independent of susceptibility to weight gain. Daily fat consumption in a nutritious source (DIO-diet; analogous to a fatty meal) promoted overeating and weight gain but limiting fat to daily non-nutritive food (PF+chow; analogous to a snack with a low fat meal), did not. The data offer an animal model of lean and obese binge-eating, and obesity with and without binge-eating that can be used to identify the unique physiology of these groups and henceforth suggest more specifically targeted treatments for binge-eating and obesity.

Cardamom powder supplementation prevents obesity, improves glucose intolerance, inflammation and oxidative stress in liver of high carbohydrate high fat diet induced obese rats.

Science.gov (United States)

Rahman, Md Mizanur; Alam, Mohammad Nazmul; Ulla, Anayt; Sumi, Farzana Akther; Subhan, Nusrat; Khan, Trisha; Sikder, Bishwajit; Hossain, Hemayet; Reza, Hasan Mahmud; Alam, Md Ashraful

2017-08-14

Cardamom is a well-known spice in Indian subcontinent, used in culinary and traditional medicine practices since ancient times. The current investigation was untaken to evaluate the potential benefit of cardamom powder supplementation in high carbohydrate high fat (HCHF) diet induced obese rats. Male Wistar rats (28 rats) were divided into four different groups such as Control, Control + cardamom, HCHF, HCHF + cardamom. High carbohydrate and high fat (HCHF) diet was prepared in our laboratory. Oral glucose tolerance test, organs wet weight measurements and oxidative stress parameters analysis as well as liver marker enzymes such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) activities were assayed on the tissues collected from the rats. Plasma lipids profiles were also measured in all groups of animals. Moreover, histological staining was also performed to evaluate inflammatory cells infiltration and fibrosis in liver. The current investigation showed that, HCHF diet feeding in rats developed glucose intolerance and increased peritoneal fat deposition compared to control rats. Cardamom powder supplementation improved the glucose intolerance significantly (p > 0.05) and prevented the abdominal fat deposition in HCHF diet fed rats. HCHF diet feeding in rats also developed dyslipidemia, increased fat deposition and inflammation in liver compared to control rats. Cardamom powder supplementation significantly prevented the rise of lipid parameters (p > 0.05) in HCHF diet fed rats. Histological assessments confirmed that HCHF diet increased the fat deposition and inflammatory cells infiltration in liver which was normalized by cardamom powder supplementation in HCHF diet fed rats. Furthermore, HCHF diet increased lipid peroxidation, decreased antioxidant enzymes activities and increased advanced protein oxidation product level significantly (p > 0.05) both in plasma and liver tissue which were modulated by

Response of gut microbiota and inflammatory status to bitter melon (Momordica charantia L.) in high fat diet induced obese rats.

Science.gov (United States)

Bai, Juan; Zhu, Ying; Dong, Ying

2016-12-24

Bitter melon (Momordica charantia L.) is rich in a variety of biologically active ingredients, and has been widely used in traditional Chinese medicine (TCM) to treat various diseases, including type 2 diabetes and obesity. We aimed to investigate how bitter melon powder (BMP) could affect obesity-associated inflammatory responses to ameliorate high-fat diet (HFD)-induced insulin resistance, and investigated whether its anti-inflammatory properties were effected by modulating the gut microbiota. Obese SD rats (Sprague-Dawley rats, rattus norregicus) were randomly divided into four groups: (a) normal control diet (NCD) and distilled water, (b) HFD and distilled water, (c) HFD and 300mg BMP/kg body weight (bw), (d) HFD and 10mg pioglitazone (PGT)/kg bw. We observed remarkable decreases in the fasting glucose, fasting insulin, HOMA-IR index, serum lipid levels, and cell sizes of epididymal adipose tissues in the BMP and PGT groups after 8 weeks. BMP could significantly improve the proinflammatory cytokine tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), anti-inflammatory cytokine interleukin-10 (IL-10), and local endotoxin levels compared to the HFD group (p<0.05). BMP suppressed the activation of nuclear factor-κB (NF-κB) by inhibiting inhibitor of NF-κB alpha (IκBα) degradation and phosphorylation of c-Jun N-terminal kinase/ p38 mitogen-activated protein kinases (JNK/p38 MAPKs) in adipose tissue. Sequencing results illustrated that BMP treatment markedly decreased the proportion of the endotoxin-producing opportunistic pathogens and increased butyrate producers. These results demonstrate that BMP ameliorates insulin sensitivity partly via relieving the inflammatory status in the system and in white adipose tissues of obese rats, and is associated with a proportional regulation of specific gut microbiota. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Reduced bone mass in obese young rats through PPAR omega suppression of wnt/beta-catenin signaling and direct action of free fatty acids (NEFA)

Science.gov (United States)

The relationship of obesity to skeletal development is unclear. We utilized total enteral nutrition to feed high and low fat diets (HFD and LFD) to rats for 4 wks to produce obesity. Weight gain was matched but fat mass, serum leptin and NEFA were increased by HFD (P < 0.05). HFD lowered total bone ...

Effect of 3-keto-1,5-bisphosphonates on obese-liver's rats.

Science.gov (United States)

Lahbib, Karima; Touil, Soufiane

2016-10-01

Obesity is associated with an oxidative stress status, which is defined by an excess of reactive oxygen species (ROS) vs. the antioxidant defense system. We report in this present work, the link between fat deposition and oxidative stress markers using a High Fat Diet-(HFD) induced rat obesity and liver-oxidative stress. We further determined the impact of chronic administration of 3-keto-1, 5-BPs 1 (a & b) (40μg/kg/8 weeks/i.p.) on liver's level. In fact, exposure of rats to HFD during 16 weeks induced body and liver weight gain and metabolic disruption with an increase on liver Alanine amino transférase (ALAT) and Aspartate aminotransférase (ASAT) concentration. HFD increased liver calcium level as well as free iron, whereas, it provoked a decrease on liver lipase activity. HFD also induced liver-oxidative stress status vocalized by an increase in reactive oxygen species (ROS) as superoxide radical (O 2 ), hydroxyl radical (OH) and Hydrogen peroxide (H 2 O 2 ). Consequently, different deleterious damages as an increase on Malon Dialdehyde MDA, Carbonyl protein PC levels with a decrease in non-protein sulfhydryls NPSH concentrations, have been detected. Interestingly, our results demonstrate a decrease in antioxidant enzymes activities such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidases (GPx) and peroxidases (POD). Importantly, 3-keto-1,5-bisphosphonates treatment corrected the majority of the deleterious effects caused by HFD, but it failed to correct some liver's disruptions as mineral profile, oxidative damages (PC and NPSH levels) as well as SOD and lipase activities. Our investigation point that 3-keto-1,5-bisphosphonates could be considered as safe antioxidant agents on the hepatic level that should also find other potential biological applications. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Dietary fat and bile juice, but not obesity, are responsible for the increase in small intestinal permeability induced through the suppression of tight junction protein expression in LETO and OLETF rats

Directory of Open Access Journals (Sweden)

Suzuki Takuya

2010-03-01

Full Text Available Abstract Background An increase in the intestinal permeability is considered to be associated with the inflammatory tone and development in the obesity and diabetes, however, the pathogenesis of the increase in the intestinal permeability is poorly understood. The present study was performed to determine the influence of obesity itself as well as dietary fat on the increase in intestinal permeability. Methods An obese rat strain, Otsuka Long Evans Tokushima Fatty (OLETF, and the lean counter strain, Long Evans Tokushima Otsuka (LETO, were fed standard or high fat diets for 16 weeks. Glucose tolerance, intestinal permeability, intestinal tight junction (TJ proteins expression, plasma bile acids concentration were evaluated. In addition, the effects of rat bile juice and dietary fat, possible mediators of the increase in the intestinal permeability in the obesity, on TJ permeability were explored in human intestinal Caco-2 cells. Results The OLETF rats showed higher glucose intolerance than did the LETO rats, which became more marked with the prolonged feeding of the high fat diet. Intestinal permeability in the OLETF rats evaluated by the urinary excretion of intestinal permeability markers (Cr-EDTA and phenolsulfonphthalein was comparable to that in the LETO rats. Feeding the high fat diet increased intestinal permeability in both the OLETF and LETO rats, and the increases correlated with decreases in TJ proteins (claudin-1, claudin-3, occludin and junctional adhesion molecule-1 expression in the small, but not in the large intestine (cecum or colon. The plasma bile acids concentration was higher in rats fed the high fat diet. Exposure to bile juice and the fat emulsion increased TJ permeability with concomitant reductions in TJ protein expression (claudin-1, claudin-3, and junctional adhesion molecule-1 in the Caco-2 cell monolayers. Conclusion Excessive dietary fat and/or increased levels of luminal bile juice, but not genetic obesity, are

Effect of exogenous leptin on serum levels of lipids, glucose, renal and hepatic variables in both genders of obese and streptozotocin-induced diabetic rats

Directory of Open Access Journals (Sweden)

Parichehr Hayatdavoudi

2015-11-01

Full Text Available Objective(s: Leptin exerts various effects on appetite and body weight. Disruption of the obesitygene is precedent to fatness. Insulin or glucose elevates leptin, but streptozotocin reduces it. However, controversial data exist for the effects of leptin on diabetes and leptin level in each gender. Leptin can damage the kidney function but little evidence exists for its hepatic effects. The aim of this study was to investigate the probable sex-dependent differences in blood sugar levels, lipid profile, and renal and hepatic biochemical factors in the obesity and streptozotocin-induced diabetic rats after leptin administration. Materials and Methods: Wistar rats of both sexes were randomly divided into two groups, namely obese and diabetic rats. Each group was further divided into male and female subgroups. Extra fat and carbohydrate was added to the diet to induce obesity. Furthermore, streptozotocin (55 mg/kg, IP was injected to induce diabetes. The treatment groups received leptin (0.1 mg/kg SC for 10 days, and then, blood samples were taken from the orbital sinus for laboratory evaluations. Results: Leptin resulted in a significant weight loss in both sexes (P

[Study on the weight-reducing effect of Acer truncatum leave extract in alimentary obesity rat].

Science.gov (United States)

Gao, Lifang; Cao, Lige; Tian, Mi; Chen, Zhenliang

2012-07-01

To investigate the weight-reducing effect of Acer truncatum leave extract on alimentary obesity rats and its effect on fatty acid synthase (FAS). SPF-grade adult male Wistar rats were fed with high-fat diet and Acer truncatum leave extract (10, 30 and 100 mg/kg BW) was given by gavage once a day for 31 days. Body weight (BW), adipose weight and food consumption were recorded, and the activity of hepatic fatty acid synthase (FAS) was measured. Compared with the model-control group, body weight, adipose weight and the ratio of adipose weight to body weight were obviously lower in 30 mg/kg BW and 100 mg/kg BW groups (P Acer truncatum leave extract on reducing body weight.

Patterns of hyperphagia in the Zucker obese rat: a role for fat cell size and number?

Science.gov (United States)

Vasselli, J R

1985-06-01

The hypothesis that adipocyte size and number influence feeding behavior, via as yet unidentified signals to the CNS, is reviewed. The proposal is made that, due to several metabolic alterations which favor lipid deposition, the genetically obese Zucker rat (fafa) may be an appropriate model in which to study feeding-adipose tissue relationships. Data from several studies are presented demonstrating that the developing male Zucker fatty rat displays hyperphagia during the growth period which reaches a peak, or "break point," and then declines such that intake of fatty and lean rats becomes comparable at approximately 20 weeks of age. Beyond week 20, cycles of hyperphagia of several weeks' duration can be detected in fatty rats. The above feeding changes are related to data showing that on a laboratory chow-type diet, adipocytes approach maximal size at 15-16 weeks in the fatty rat, while accelerated proliferation of adipocytes takes place following week 20. During growth, responding for food in an operant task by fatty rats varies in accord with the pattern of hyperphagia. Further studies in the fatty rat show that the duration and magnitude of developmental hyperphagia can be altered by manipulating the caloric density and macronutrient content of the diet, with fat containing diets leading to the earliest break point of developmental hyperphagia. Some theoretical problems with the notion of adipose tissue feedback control of feeding behavior are discussed.

l-Leucine Supplementation Worsens the Adiposity of Already Obese Rats by Promoting a Hypothalamic Pattern of Gene Expression that Favors Fat Accumulation

Directory of Open Access Journals (Sweden)

Thais T. Zampieri

2014-04-01

Full Text Available Several studies showed that l-leucine supplementation reduces adiposity when provided before the onset of obesity. We studied rats that were exposed to a high-fat diet (HFD for 10 weeks before they started to receive l-leucine supplementation. Fat mass was increased in l-leucine-supplemented rats consuming the HFD. Accordingly, l-leucine produced a hypothalamic pattern of gene expression that favors fat accumulation. In conclusion, l-leucine supplementation worsened the adiposity of rats previously exposed to HFD possibly by central mechanisms.