Astragaloside IV prevents high-fat diet induced obesity partially through enhancing leptin signaling transduction

Aim To investigate the effects of astragaloside IV （ASI） on high-fat diet （HFD） induced obese mice. Methods The male mice aged 6 weeks were randomly divided into three groups （u- 18/group）, namely control group, model group and ASI-treated group. Control group were fed with standard diet, whereas the other two groups were given high fat diet. ASI-treated mice were daily intraperitoneally injected with ASI （25 nag · kg^-1）. Mean- while, the other group mice were treated with saline. Body weight of mice was monitored every week and lasted for 13 weeks. Serum cholesterol and triglyceride content were measured with respective kits. Serum leptin level was deter- mined by ELISA kit. Expression of leptin receptor in hypothalamus was measured by Western blot assay. Gene ex- pression of neuropeptide Y （NPY） and agouti-related protein （AGRP） in hypothalamus was detected by qPCR assay. In addition, leptin receptor-deficient db/db mice were given intraperitoneally with ASI （25 mg ~ kg-1） or saline for 13 weeks （u- 8/group）. Results ASI blocked body weight gain, suppressed appetite, improved leptin resistance, lowered serum triacylglycerol （TG） and total cholesterol （TC） contents, reduced accumulation of fat tissues and pre- vented enlargement of adipose cells in HFD fed mice. Furthermore, ASI increased the protein expression level of lep- tin receptor in hypothalamus, and inhibited the mRNA expression levels of NPY and AGRP. However, ASI could not decrease body gain in leptin receptor - deficient db/db mice as well as the mRNA expression levels of NPY and AGRP. Conclusion The study suggested that ASI could efficiently prevent HFD-induced obesity in C57BL/6 mice,which was partially mediated through enhancing leptin signaling transduction.

High-fat diet and oral infection induced type 2 diabetes and obesity development under different genetic backgrounds

Background:Type 2 diabetes(T2D)is an adult-onset and obese form of diabetes caused by an interplay between genetic,epigenetic,and environmental components.Here,we have assessed a cohort of 11 genetically different collaborative cross(CC)mouse lines comprised of both sexes for T2D and obesity developments in response to oral infection and high-fat diet(HFD)challenges.Methods:Mice were fed with either the HFD or the standard chow diet(control group)for 12 weeks starting at the age of 8 weeks.At week 5 of the experiment,half of the mice of each diet group were infected with Porphyromonas gingivalis and Fusobacterium nucleatum bacteria strains.Throughout the 12-week experimental period,body weight(BW)was recorded biweekly,and intraperitoneal glucose tolerance tests were performed at weeks 6 and 12 of the experiment to evaluate the glucose tolerance status of mice.Results:Statistical analysis has shown the significance of phenotypic variations between the CC lines,which have different genetic backgrounds and sex effects in different experimental groups.The heritability of the studied phenotypes was estimated and ranged between 0.45 and 0.85.We applied machine learning methods to make an early call for T2D and its prognosis.The results showed that classification with random forest could reach the highest accuracy classification(ACC=0.91)when all the attributes were used.Conclusion:Using sex,diet,infection status,initial BW,and area under the curve(AUC)at week 6,we could classify the final phenotypes/outcomes at the end stage of the experiment(at 12 weeks).

Green coffee bean extract improves obesity by decreasing body fat in high-fat diet-induced obese mice

Objective:To evaluate possible lipid catabolism and body fat regulation effects of 3-caffeoylquinic acid in Green coffee bean extract(GCBE) in high-fat diet(HFD)-induced obese mice.Methods:Obesity was induced in mice using a HFD for four weeks.Then,mice were fed only HFD or HFD with GCBE at 50,100,and 200 mg/kg.Fatty acid synthesis mechanism regulation of body fat was investigated through real-time PCR and Western blot assay.Body fat reduction was measured through dual-energy X-ray absorptiometry.Results:In HFD-induced obese mice,GCBE treatment significantly decreased body weight gain,liver weight and white adipose tissue weights with regulation of adipose tissue lipolysis hormones,like adiponectin and leptin.GCBE treatment decreased mR NA expression levels of adipogenesis and adipocyte metabolism related genes in adipose tissues and the liver,and decreased the corresponding protein expression.Dual energy X-ray absorptiometry measurements were used to compare body fat between mice on high-fat and those treated with GCBE.GCBE treated mice had a lower fat mass compared to HFD alone fed mice and relative body weight and fat mass were markedly decreased.Conclusions:GCBE has a potential anti-obesity effect with lowering body fat accumulation by regulating adipogenesis and lipid metabolism-related genes and proteins in WAT and liver.

Effects of ginseng dietary supplementation on a high-Fat diet-induced obesity in C57BL/6 Mice

Excess caloric intake increases the amount of adipose tissue and contributes to metabolic disorders in disrupted metabolic homeostasis.This study aimed to investigate the anti-obesity effects of ginseng and the alternation of gut microbiota composition in high-fat diet(HFD)-induced obesity.The results showed that HFD treatment influenced body weight gain,adipose tissue accumulation and biochemical parameter changes.Compared to the HFD group,ginseng supplementation of HFD-fed mice decreased body weight,adipose tissue mass,total cholesterol(T-CHO)and high-density lipoprotein(HDL)/low-density lipoprotein(LDL)ratio.To analysis the alterations of gut microbiota,ginseng in dietary supplements decreased Firmicutes abundance and increased Bacteroidetes abundance.Taken together,these findings suggest ginseng may modulate the energy storage and alter gut microbiota composition.

Interaction of Dietary Composition and PYY Gene Expression in Diet-induced Obesity in Rats

The interaction of high-fat diet and the peptide YY (PYY) gene expression in diet-induced obesity and the mechanisms which predisposed some individuals to become obese on high-fat diet were explored. Thirty-six male SD rats were randomly divided into high-fat diet group (n=27) and chow fed control group (n=9). After 15 weeks of either a high-fat diet or chew fed diet, the high-fat diet group was subdivided into dietary induced obesity (DIO) and dietary induced obesity resistant (DIR) group according to the final body weight. Then the DIO rats were subdivided into two groups for a 8-week secondary dietary intervention. One of the group was switched to chew fed diet, whereas the other DIO and DIR rats continued on the initial high-fat diet. Weight gain and food intake were measured, food efficiency was calculated, and the concentrations of plasma neuropeptide Y (NPY) and PYY were assayed. Hypothalamic NPY mRNA expression and PYY mRNA expression in ileum and colon was detected by RT-PCR. The results showed that at the end of 15th week, the levels of body weight and caloric intake were significantly higher in DIO group than in DIR or control group (P<0.01), while no significant difference was found between DIR and control group (P>0.05). The concentration of plasma PYY was significantly higher in DIR group than in DIO and CF group, while no significant difference was found between DIO and CF group (P<0.01). After switching the DIO rats to chow fed diet, their body weight gains were significantly lower than that of the DIO-HF group. The expression of PYY mRNA was increased in DIO-HF/CF rats than in DIO-HF rats, and the expression of hypothalamic NPY mRNA was decreased in DIO-HF/CF rats than in DIO-HF group. It was concluded that both dietary composition and PYY gene expression could potently alter the hypothalamic NPY expression and result in different susceptibility to obese and overeating. The decreased PYY was associated with the increased NPY expression and their predisposal to obese and overeating in rats.

Monascus pilosus-fermented black soybean inhibits lipid accumulation in adipocytes and in high-fat diet-induced obese mice

Objective:To explore the anti-obesity effects and the mechanism of action of Monascus pilosus(M.pilosus)-fermented black soybean(MFBS)extracts(MFBSE)and MFBS powders(MFBSP)in adipocytes and high-fat diet(HFD)-induced obese mice,respectively.Methods:Black soybean was fermented with M.pilosus,and the main constituents in MFBS were analyzed by HPLC analysis.In vitro,MFBSE were examined for anti-adipogenic effects using Oil-Red O staining.In vivo,mice were fed a normal-fat diet(NFD)control,HFD control or HFD containing 1 g/kg MFBSP for 12 weeks,and then body weight gain and tissues weight measured.Real-time PCR and western blot assay were used to determine the mechanism of anti-adipogenic effects.Results:MFBSE inhibited lipid accumulation in 3T3-L1 adipocytes without exerting cell cytotoxicity.MFBSP treatment in HFD-fed mice significantly decreased the body weight gain compared with the HFD control mice.MFBSE and MFBSP treatment resulted in significantly lower mRNA levels of adipogenesis-related genes,such as peroxisome proliferator-activated receptorγ(PPARγ),fatty acid-binding protein 4(FABP4),and fatty acid synthase(FAS),in adipocytes and in white adipose tissue(WAT)of HFD-induced obese mice.Conclusions:These results suggest that the anti-obesity effects of MFBS are elicited by regulating the expression of adipogenesis-related genes in adipocytes and WAT of HFDinduced obese mice.

Impact of age on host responses to diet-induced obesity:Development of joint damage and metabolic set points

Background:Osteoarthritis is one of the leading causes of pain and disability worldwide,and a large percentage of patients with osteoarthritis are individuals who are also obese.In recent years,a series of animal models have demonstrated that obesity-inducing diets can result in synovial joint damage(both with and without the superimposition of trauma),which may be related to changes in percentage of body fat and a series of low-level systemic inflammatory mediators.Of note,there is a disparity between whether the dietary challenges commence at weaning,representing a weanling onset,or at skeletal maturity,representing an adult onset of obesity.We wished to evaluate the effect ofthe dietary exposure time and the age at which animals are exposed to a high-fat and high-sucrose(HFS) diet to determine whether these factors may result in disparate outcomes,as there is evidence suggesting that these factors result in differential metabolic disturbances.Based on dietary exposure time,we hypothesized that rats fed an HFS diet for 14 weeks from weaning(HFS Weanling) would demonstrate an increase in knee joint damage scores,whereas rats exposed to the HFS diet for 4 weeks,starting at 12 weeks of age(HFS Adult) and rats exposed to a standard chow diet(Chow)would not display an increase in knee joint damage scores.Methods:Male Sprague-Dawley rats were fed either an HFS diet for 14 weeks from weaning(HFS Weanling) or an HFS diet for 4 weeks,starting at 12 weeks of age(HFS Adult).At sacrifice,joints were scored using the modified Mankin Criteria,and serum was analyzed for a defined subset of inflammatory markers(Interleukin-6,leptin,monocyte chemoattractant protein-1,and tumor necrosis factorα).Results:When the HFS Weanling and HFS Adult groups were compared,both groups had a similar percent of body fat,although the HFS Weanling group had a significantly greater body mass than the HFS Adult group.The HFS Weanling and HFS Adult animals had a significant increase in body mass and percentage of body fat when compared to the Chow group.Although knee joint damage scores were low in all 3 groups,we found,contrary to our hypothesis,that the HFS Adult group had statistically significant greater knee joint damage scores than the Chow and HFS Weanling groups.Furthermore,we observed that the HFS Weanling group did not have significant differences in knee joint damage scores relative to the Chow group.Conclusion:These findings indicate that the HFS Weanling animals were better able to cope with the dietary challenge of an HFS diet than the HFS Adult group.Interestingly,when assessing various serum proinflammatory markers,no significant differences were detected between the HTS Adult and HFS Weanling groups.Although details regarding the mechanisms underlying an increase in knee joint damage scores in the HFS Adult group remain to be elucidated,these findings indicate that dietary exposure time maybe less important than the age at which an HFS diet is introduced.Moreover,increases in serum proinflammatory mediators do not appear to be directly linked to knee joint damage scores in the HFS Weanling group animals but may be partially responsible for the observed knee joint damage in the adults over the very short time of exposure to the HFS diet.

Comparative study on the difference of obesity model induced by two kinds of high fat diet in Sprague-Dawley rats

Objective: To explore the differences of obese Sprague-Dawley(SD)rats model induced by lard oil high-fat(HF)diet or purified HF diet. Methods: SD weanling rats were randomly divided into three groups: D1 group,where rats were fed by lard oil HF diet;D2 group,where rats were fed by purified HF diet;C group,where rats were fed on chow. After 12 weeks,diet-induced obesity rat(stop 33% based on weight)were selected for further study,and the rest rats from group D1 and D2 were excluded. The food intake and weight were weighted daily and weekly,respectively. The subcutaneous,visceral and total fat contents of rats was measured by 256-row CT scan and the Lee index was calculated accordingly. The kidney,liver,testis,spleen and heart were weighted respectively. Serum leptin and insulin levels were quantified. The pathology in liver and adipose tissues were analyzed by HE staining. Oral glucose tolerance test(OGTT)was used to compare the glucose tolerance ability. Serum total cholestero(lT-CHO),high density lipoprotein(HDL-C),low density lipoprotein(LDL-C),triglyceride(TG)and inflammatory cytokines IL-6,TNF-α were detected as well. Results: After 12 weeks,the body weight,subcutaneous fat,visceral fat,total fat mass,wet weight of liver,kidney and heart,area under blood glucose curve and the levels of serum insulin,leptin,T-CHO,LDL-C,TG,IL-6 and TNF-α in group D2 were significantly increased compared to those of group C and group D1. HDL-C of group D2 was markedly lower than that in group C(P<0. 05). The visceral fat,total fat content and HDL-C in group D1 were significantly different from those of group C(P<0. 05). Steatosis and enlarged adipocyte were found in the livers of rats in group D1 and D2,and the lesions were more significant in group D2. Conclusion: Purified HF diet was more effective in inducing metabolic abnormalities,steatosis,peripheral chronic inflammation in obese SD rat models. But lard oil HF diet was more economical when only inducing visceral steatosis was required.

The Effects of Xylitol on Body Weight Loss Management and Lipid Profile on Diet-Induced Obesity Mice

Xylitol is an alternative sweetener which has been previously reported to have many beneficial effects such as prevention from dental caries, reduction of visceral fat and increased synthesis of collagen. However, its role in body weight loss management has not been uncovered before. This study sought to investigate the effects of xylitol on body weight loss management, blood glucose and lipid profile on diet-induced obesity (DOI) mice. Fifteen male mice were subjected to high fat diet (60 kcal%) and normal drinking water for 28 days and then randomly divided into three (control, glucose and xylitol) groups. Each group of mice was then fed with normal diet for another 28 days with supplied normal drinking water (control);glucose solution 10% and xylitol solution 10%. Body weight loss was found to be significantly high in xylitol mice (2.56 ± 0.21, p = 0.003) compared to the other two groups. Lowest blood glucose level was found in the control group mice with the mean 7.65 ± 0.10 (p = 0.001). Xylitol mice had also showed the lowest total cholesterol level (4.20 ± 0.90, p = 0.000) than the other groups, but highest in HDL level (2.72 ± 0.14, p = 0.000). In conclusion, these findings proved that xylitol has the potential to reduce body weight, lowering the blood glucose but yet increase the HDL level.

Alisol B 23-acetate promotes white adipose tissue browning to mitigate high-fat diet-induced obesity by regulating mTOR-SREBP1 signaling

Objective Obesity is a global health concern with management strategies encompassing bariatric surgery and anti-obesity drugs;however,concerns regarding complexities and side effects persist,driving research for more effective,low-risk strategies.The promotion of white adipose tissue(WAT)browning has emerged as a promising approach.Moreover,alisol B 23-acetate(AB23A)has demonstrated efficacy in addressing metabolic disorders,suggesting its potential as a therapeutic agent in obesity management.Therefore,in this study,we aimed to investigate the therapeutic potential of AB23A for mitigating obesity by regulating metabolic phenotypes and lipid distribution in mice fed a high-fat diet(HFD).Methods An obesity mouse model was established by administration of an HFD.Glucose and insulin metabolism were assessed via glucose and insulin tolerance tests.Adipocyte size was determined using hematoxylin and eosin staining.The expression of browning markers in WAT was evaluated using Western blotting and quantitative real-time polymerase chain reaction.Metabolic cage monitoring involved the assessment of various parameters,including food and water intake,energy metabolism,respiratory exchange rates,and physical activity.Moreover,oil red O staining was used to evaluate intracellular lipid accumulation.A bioinformatic analysis tool for identifying the molecular mechanisms of traditional Chinese medicine was used to examine AB23A targets and associated signaling pathways.Results AB23A administration significantly reduced the weight of obese mice,decreased the mass of inguinal WAT,epididymal WAT,and perirenal adipose tissue,improved glucose and insulin metabolism,and reduced adipocyte size.Moreover,treatment with AB23A promoted the expression of browning markers in WAT,enhanced overall energy metabolism in mice,and had no discernible effect on food intake,water consumption,or physical activity.In 3T3-L1 cells,AB23A inhibited lipid accumulation,and both AB23A and rapamycin inhibited the mammalian target of rapamycin-sterol regulatory element-binding protein-1(mTOR-SREBP1)signaling pathway.Furthermore,3-isobutyl-1-methylxanthine,dexamethasone and insulin,at concentrations of 0.25 mmol/L,0.25μmol/L and 1μg/mL,respectively,induced activation of the mTOR-SREBP1 signaling pathway,which was further strengthened by an mTOR activator MHY1485.Notably,MHY1485 reversed the beneficial effects of AB23A in 3T3-L1 cells.Conclusion AB23A promoted WAT browning by inhibiting the mTOR-SREBP1 signaling pathway,offering a potential strategy to prevent obesity.

Regular moderate aerobic exercise improves high-fat diet-induced nonalcoholic fatty liver disease via monoacylglycerol O-acyltransferase 1 pathway suppression

Purpose:Monoacylglycerol O-acyltransferase 1(MGAT1)is reported to play a key role in the development of diet-induced nonalcoholic fatty liver disease(NAFLD).Thus,this study investigated the effect of exercise on suppression of the MGAT1 pathway in NAFLD tissue of high-fat diet(HFD)-induced obese rats.Methods:Male Sprague-Dawley rats were fed an HFD containing 45%fat for 6 weeks.Upon confirmation that NAFLD had been induced in the obese animals,they were divided into HFD-fed groups provided with exercise(HFD+EXE)or without exercise(HFD)and a group given dietary adjustment(DA)only,for a further 6 weeks of intervention treatment.The 6-week regular moderate aerobic exercise consisted of an accommodation phase with increasing exercise.Lipid accumulation in the liver tissue was determined by Oil Red O staining.The MGAT1 and liver lipogenic gene mRNA levels were measured by qPCR,and their protein levels by western blot assay.Results:Oil Red O staining showed that NAFLD was successfully induced by HFD-fed.The gene expression of MGAT1 was significantly lower in HFD+EXE than HFD.However,there was no significant difference between HFD+EXE and DA.The protein expression of MGAT1 was significantly lower in HFD+EXE than both HFD and DA.Messenger RNA and protein expression of other lipogenic genes were not different among groups.These data indicate that exercise suppresses MGAT1 pathway regardless of HFD feeding;in part,this effect could be greater than DA.Conclusion:Our data suggest that exercise can improve NAFLD,which is probably due to suppression of MGAT1 pathway.

Polygonatum sibiricum polysaccharides protect against obesity and non-alcoholic fatty liver disease in rats fed a high-fat diet

Polygonatum sibiricum is a traditional medicinal and dietary plant of the family Liliaceae. The main functional macromolecules of P. sibiricum are polysaccharides, which function in antioxidation and regulating immunity. Previous studies have shown that insulin resistance(IR), oxidative stress, and inflammation are important factors in the induction of lipid metabolic diseases such as obesity. Therefore, in this study, we established a high-fat diet-induced rat model of obesity and nonalcoholic fatty liver disease(NAFLD) to explore the potential protective effect of P. sibiricum polysaccharides(PSPs) and the mechanisms behind it. After 4 weeks of high-fat diet feeding to induce obesity, the rats were treated with different doses of PSP solution or distilled water for 6 weeks. Compared with untreated obese rats, PSP-treated obese rats showed a decrease in body weight, serum total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels, hepatic aspartate aminotransferase and alanine aminotransferase activity, hepatic malondialdehyde content, and hepatic levels of the pro-inflammatory factors tumor necrosis factor-α, interleukin-1β, and interleukin-6, as well as increased serum high-density lipoprotein cholesterol levels and hepatic superoxide dismutase, catalase, and glutathione peroxidase activity. Pathological analysis and immunoblotting of the liver tissues indicated that mechanistically, PSPs reduced obesity and NAFLD in rats by upregulating insulin receptor expression, increasing adenosine monophosphate-activated protein kinase phosphorylation, and downregulating sterol regulatory element-binding protein 2 and low-density lipoprotein receptor expression, thus promoting lipid metabolism, decreasing body weight, and reducing inflammation and oxidative stress caused by lipid accumulation. Based on these results, PSPs may have the potential to reduce obesity and NAFLD associated with a high-fat diet.

Studying host genetic background effects on multimorbidity of intestinal cancer development,type 2 diabetes and obesity in response to oral bacterial infection and high-fat diet using the collaborative cross(CC)lines

Background:Multimorbidity of intestinal cancer(IC),type 2 diabetes(T2D)and obesity is a complex set of diseases,affected by environmental and genetic risk factors.High-fat diet(HFD)and oral bacterial infection play important roles in the etiology of these diseases through inflammation and various biological mechanisms.Methods:To study the complexity of this multimorbidity,we used the collaborative cross(CC)mouse genetics reference population.We aimed to study the multimorbidity of IC,T2D,and obesity using CC lines,measuring their responses to HFD and oral bacterial infection.The study used 63 mice of both sexes generated from two CC lines(IL557 and IL711).For 12 weeks,experimental mice were maintained on specific dietary regimes combined with co-infection with oral bacteria Porphyromonas gingivalis and Fusobacterium nucleatum,while control groups were not infected.Body weight(BW)and results of a intraperitoneal glucose tolerance test(IPGTT)were recorded at the end of 12 weeks,after which length and size of the intestines were assessed for polyp counts.Results:Polyp counts ranged between 2 and 10 per CC line.The combination of HFD and infection significantly reduced(P<.01)the colon polyp size of IL557 females to 2.5 cm 2,compared to the other groups.Comparing BW gain,IL557 males on HFD gained 18 g,while the females gained 10 g under the same conditions and showed the highest area under curve(AUC)values of 40000-45000(min mg/dL)in the IPGTT.Conclusion:The results show that mice from different genetic backgrounds respond differently to a high fat diet and oral infection in terms of polyp development and glucose tolerance,and this effect is gender related.

Assessing the host genetic background effects on type 2 diabetes and obesity development in response to mixed–oral bacteria and high-fat diet using the collaborative cross mouse model

Background: Host genetic background and sex, play central roles in defining the pathogenesis of type 2 diabetes(T2 D), obesity and infectious diseases. Our previous studies demonstrated the utilization of genetically highly diverse inbred mouse lines, namely collaborative cross(CC), for dissecting host susceptibility for the development of T2 D and obesity, showing significant variations following high-fat(42% fat) diet(HFD). Here, we aimed to assessing the host genetic background and sex effects on T2 D and obesity development in response to oral-mixed bacterial infection and HFD using the CC lines.Materials and Methods: Study cohort consists of 97 mice from 2 CC lines(both sexes), maintained on either HFD or Standard diet(CHD) for 12 weeks. At week 5 a group of mice from each diet were infected with Porphyromonas gingivalis(Pg) and Fusobacterium nucleatum(Fn) bacteria(control groups without infection). Body weight(BW) and glucose tolerance ability were assessed at the end time point of the experiment.Results: The CC lines varied(P <.05) at their BW gain and glucose tolerance ability(with sex effect) in response to diets and/or infection, showing opposite responses despite sharing the same environmental conditions. The combination of diet and infection enhances BW accumulation for IL1912, while restraints it for IL72. As for glucose tolerance ability, only females(both lines) were deteriorated in response to infection.Conclusions: This study emphasizes the power of the CC mouse population for the characterization of host genetic makeup for defining the susceptibility of the individual to development of obesity and/or impaired glucose tolerance.

Rapeseed polysaccharides alleviate overweight induced by high-fat diet with regulation of gut microbiota in rats

High-fat diet(HFD)could induce obese and microbial dysbiosis,the latter of which has great impact on host health.Dietary polysaccharides are well known to have a wide range of biological benefits for bowel health.In this study,we investigated the effects of rapeseed polysaccharide(RSP)on overweight and gut microbiota in highfat-diet(HFD)fed rats.RSP effectively alleviated the hyperglycemia and lipid metabolic disorder in serum,which was found closely related to the modulation of intestinal microbiota.Supplementation of RSP regulated the intestinal microbiome by increasing the proportion of butyrate acid producer Blautia(P<0.05),Dorea(P<0.01)and Akkermansia genus and inhibiting the growth of bacterial species associated with inflammation such as unclassified Ruminococcaceae(P<0.05).Moreover,the restoration of total short-chain fatty acids(SCFAs),especially propionate and butyrate might be an important strategy for mitigating HFD induced metabolic disorders.Our results suggested that RSP is a potential prebiotic for preventing obese induced HFD through regulating the gut microbiota.

Effects of feeding a diet containing Gymnema sylvestre extract: attenuating progression of obesity in C57BL/6J mice

Objective: To investigate the effect of Gymnema sylvestre extract(GS) on initial anti-obesity, liver injury, and glucose homeostasis induced by a high-fat diet(HFD). Methods: The dry powder of GS was extracted with methanol, and gymnemic acid was identified by high performance liquid chromatography as deacyl gymnemic acid. Male C57BL/6J mice that fed on either a normal diet, normal diet containing 1 g/kg GS(CON+GS) HFD, or HFD containing 1.0 g/kg GS(HFD+GS) for 4 weeks were used to test the initial anti-obesity effect of GS. Body weight gain and food intake, and serum levels about lipid and liver injury markers were measured. Histopathology of adipose tissue and liver stained with hematoxylin and eosin(H&E) and oil-red O were analyzed. After 4 weeks of GS extract feeding, intraperitoneal glucose tolerance test(IPGTT) was performed. Results: The methanol extracts of GS exerted significant anti-obesity effects in HFD+GS group. They decreased body weight gain, a lower food and energy efficiency ratio, and showed lower serum levels of total cholesterol(TC), triglyceride(TG), low-density lipoprotein(LDL)-cholesterol, very-low density lipoprotein(VLDL)-cholesterol and leptin compared with the HFD group. The decreases of abdominal as well as epididymal fat weight and adipocyte hypertrophy, lipid droplets in liver, and serum levels of aspartate aminotransferase(AST) and alanine transaminase(ALT) were also observed. The CON+GS group showed an effect of glucose homeostasis compared to the CON group. Conclusions: This study shows that GS provide the possibility as a key role in an initial anti-obesity effects feeding with a HFD.

SESN2 ablation weakens exercise benefits on resilience of gut microbiota following high-fat diet consumption in mice

Gut dysbiosis is associated with several pathological processes.Previous study showed that regular exercise can protect against dysmetabolism in high-fat diet(HFD)fed mice through butyrate-SESN2 pathway,and SESN2 ablation weakened the protective effects of exercise.Here,we investigated whether SESN2-defi ciency suppresses the exercise response to microbiota composition and subsequently reduces the benefi ts of exercise on dysmetabolism induced by HFD.Wild type(WT)and SESN2^(-/-)mice were assigned to fi ve-groups,fed with either normal chow or HFD and with or without exercise training for 15-week.Fecal microbiota composition and function were assessed by 16S rRNA sequencing.The sequencing results showed that SESN2^(-/-)mice displayed differed microbiome profile from WT mice.Exercise enriched the microflora diversity and increased the benefi cial microbial species in WT mice,and SESN2 ablation weakened the benefi cial effects of exercise on microbial resilience following HFD consumption.Moreover,network analysis revealed that exercise increased correlation density and clustering of operational taxonomic units in WT mice only.KEGG demonstrated that some dominant metabolism-related enzymes and modules increased in SESN2^(-/-)mice.Our results indicated that the effects of exercise on metabolism are associated with the perturbations of gut microbiota composition and function,suggesting that SESN2 contributes to maintain metabolic homeostasis.

Obesity and cancer stem cells:Roles in cancer initiation,progression and therapy resistance

Obesity,the global pandemic since industrialization,is the number one lifestylerelated risk factor for premature death,which increases the incidence and mortality of various diseases and conditions,including cancer.In recent years,the theory of cancer stem cells(CSCs),which have the capacity for self-renewal,metastasis and treatment resistance,has been bolstered by increasing evidence.However,research on how obesity affects CSCs to facilitate cancer initiation,progression and therapy resistance is still in its infancy,although evidence has already begun to accumulate.Regarding the ever-increasing burden of obesity and obesity-related cancer,it is pertinent to summarize evidence about the effects of obesity on CSCs,as elucidating these effects will contribute to the improvement in the management of obesity-related cancers.In this review,we discuss the association between obesity and CSCs,with a particular focus on how obesity promotes cancer initiation,progression and therapy resistance through CSCs and the mechanisms underlying these effects.In addition,the prospect of preventing cancer and targeting the mechanisms linking obesity and CSCs to reduce cancer risk or to improve the survival of patients with cancer is considered.

High-fat-induced intestinal permeability dysfunction associated with altered fecal bile acids

AIM:To investigate whether high-fat-feeding is associated with increased intestinal permeability via alterations in bile acid metabolism.METHODS:Male C57Bl/6J mice were fed on a high-fat (n=26) or low-fat diet (n=24) for 15 wk.Intestinal permeability was measured from duodenum,jejunum,ileum and colon in an Ussing chamber system using 4 kDa FITC-labeled dextran as an indicator.Fecal bile acids were analyzed with gas chromatography.Segments of jejunum and colon were analyzed for the expression of farnesoid X receptor (FXR) and tumor necrosis factor (TNF).RESULTS:Intestinal permeability was significantly increased by high-fat feeding in jejunum (median 0.334 for control vs 0.393 for high-fat,P=0.03) and colon (0.335 for control vs 0.433 for high-fat,P=0.01),but not in duodenum or ileum.The concentration of nearly all identified bile acids was significantly increased by high-fat feeding (P<0.001).The proportion of ursodeoxycholic acid (UDCA) in all bile acids was decreased (1.4%±0.1% in high-fat vs 2.8%±0.3% in controls,P<0.01) and correlated inversely with intestinal permeability (r=-0.72,P=0.01).High-fat feeding also increased jejunal FXR expression,as well as TNF expression along the intestine,especially in the colon.CONCLUSION:High-fat-feeding increased intestinal permeability,perhaps by a mechanism related to bile acid metabolism,namely a decreased proportion of fecal UDCA and increased FXR expression.

Effects of Polygonatum sibiricum Polysaccharide (PSP) on Inflammatory Factors in Rats Fed on High-fat Diet

[Objectives]This study was conducted to explore the effects of Polygonatum sibiricum polysaccharide(PSP)on chronic intestinal inflammation caused by high-fat diet.[Methods]Thirty five male healthy SD rats were randomly divided into a normal control group(NC,normal diet,n=10)and a high-fat diet group(HF,high-fat diet,n=25).After 8 weeks,an obesity model was established.The HF group was randomly divided into an HF group and a PSP treatment group[PSP,300 mg/(kg·d)].After 6 weeks of intervention with PSP,rat serum was collected,and the spleen and thymus were stripped,and weighed.Serum IgG,IgM,LPS and IL-1βand IL-6 contents were detected by ELISA,and HE staining was adopted to observe the pathological changes of the colon tissue.[Results]PSP reduced the level of LPS caused by high-fat diet and the levels of inflammatory factors IL-6 and TNF-α,increased the indexes of the thymus and spleen serving as immune organs,increased IgG and IgM contents,and alleviated pathological damage to the colon tissue caused by high-fat diet.[Conclusions]This study provides a theoretical basis and experimental basis for the development of drugs for treating metabolic diseases such as obesity and inflammation.