Paternally multi-generational high-fat diet causes obesity and metabolic disorder through intergenerational DNA methylation

Gardenia jasminoides Ellis is abundant in crocin and has a longstanding historical usage both as a dietary and natural ethnic medicine. Enhanced studies have increasingly revealed the intricate interplay between glycolipid metabolism and gut microbiota, wherein their imbalance is regarded as a pivotal indicator of metabolic disorders. Currently, the precise molecular mechanism of the crude extract of crocin from Gardenia jasminoides Ellis (GC) targeting gut microbiota to regulate glycolipid metabolism disorder is still unclear. Firstly, we explored the effect of GC on digestive enzymes (α-amylase and α-glucosidase) in vitro. Secondly, we investigated the effect of GC on the physical and chemical parameters of high-fat diet (HFD) rats, such as body weight change, fasting blood glucose and lipid levels, and liver oxidative stress and injury. Then, 16S rDNA sequencing was used to analyze the effects of GC on the composition and structure of gut microbiota. Finally, the impact of GC on the TLR4/Myd88/NF-κB signaling pathway in the intestine was assessed by Western Blotting. In the present study, GC was found to exhibit a hypoglycemic effect in vitro, by inhibition of digestive enzymes. In animal experiments, we observed that GC significantly reduced fasting blood glucose, TC, and TG levels while increasing HDL-C levels. Additionally, GC demonstrated hepatoprotective properties by enhancing liver antioxidative capacity through the upregulation of SOD, CAT, and GSH-Px, while reducing ROS. 16S rDNA sequencing results showed that GC had a significant effect on the gut microbiota of HFD rats, mainly by reducing the ratio of Firmicutes/Bateroidota, and significantly affected the genera related to glycolipid metabolism, such as Akkermansia, Ligilactobacillus, Lactobacillus, Bacteroides, Prevotellaceae, etc. The Western Blotting results demonstrated that GC effectively downregulated the protein expressions of TLR4, Myd88, and NF-κB in the intestine of HFD rats, indicating that GC could target the TLR4/Myd88/NF-κB pathway to interfere with glycolipid metabolism disorder. Correlation analysis revealed that GC could target the Akkermansia-TLR4/Myd88/NF-κB pathway axis which attenuates glycolipid metabolism disorder. Therefore, this study establishes the foundation for GC as a novel therapeutic agent for glycolipid metabolism disorder chemoprevention, and it introduces a novel methodology for harnessing the potential of natural botanical extracts in the prevention and treatment of metabolic syndrome.

Polycystic ovary syndrome (PCOS) is one of the most common endocrinopathy disorders in premenopausal women, which is characterized by hyperandrogenemia, anovulation, and polycystic ovarian morphology (PCOM). Time-restricted feeding (TRF) is a new intermittent restriction dietary pattern, which has been shown to have positive benefits on obesity and glycolipid metabolism disorders. We aimed to explore the effect of the feeding regimen (ad libitum vs. TRF) on the glycolipid metabolism and reproductive endocrine disorders in a PCOS mouse model. PCOS mouse model was induced by continuous subcutaneous administration of dihydrotestosterone for 21 days. Mice were fed a high-fat diet (HFD) for 8 weeks on an ad libitum or time- restricted diet (from 10:30 p.m. to 6:30 a.m.). Compared to control mice, PCOS mice that received TRF treatment had significantly lower body weight, reduced adiposity, lower area under the curve (AUC) of glucose response in the oral glucose tolerance test (OGTT), and lower AUC in the insulin tolerance test (ITT). TRF also ameliorated lipid metabolism, as shown by a reduction in plasma lipid profiles (triglycerides and cholesterol) and the triglyceride content in the liver of PCOS mice. In terms of reproduction, the plasma androgen level, plasma estrogen (E2) level, and luteinizing hormone (LH)/follicle stimulating hormone (FSH) ratio in PCOS mice were significantly reduced after 8 weeks of TRF treatment. In addition, ovarian histology showed that TRF inhibits cyst formation and promotes corpus luteum formation. In conclusion, TRF improved metabolic and endocrine profiles in mice with PCOS.

Aberrant hypermethylation of promoter regions in cytosine-guanine dinucleotides (CpG) islands has been shown to be associated with transcriptional silencing of tumor-suppressor genes in many cancers. This study evaluated the methylation profile and the tumor-suppressive function of the small heterodimer partner (SHP, NR0B2) in the development of human hepatocellular carcinoma (HCC). Human HCC pathologic specimens and cell lines were used as model systems in this study. The expression of SHP is diminished in HCC pathologic specimens and cell lines by epigenetic silencing owing to SHP promoter hypermethylation. In vitro methylation decreased SHP promoter transactivation and nuclear receptor LRH-1 binding, an event that was reversed by demethylation. Overexpression of SHP inhibited HCC foci formation, arrested HCC tumor growth in xenografted nude mice, and increased the sensitivity of HCC cells to apoptotic stimuli. Further analysis of a total of 19 normal liver and 57 HCC specimens showed that down-regulation of SHP gene expression may be a common denominator of HCC. We propose that SHP functions as a novel tumor suppressor in the development of HCC. These findings provide new insight into the molecular mechanisms leading to this common cancer and may have both diagnostic and therapeutic applications.

Objective To determine the effects of high-fat diet on metabolic health outcomes in their male offspring and methylated regulation of the metabolic master regulator, peroxisome proliferator-activated receptor gamma coactivator 1-alpha (Pgc-1α) in C57BL/6 mice. Methods 8-week-old C57BL/6 male mice (n=20) were divided into two groups: the standard chow group (C, n=10) and the high fat diet group (HF, n=10) with random number table. After 12 weeks high fat diet (HFD) feed, each male mouse mated with a female sibling. Male pups were divided into two groups: male offspring from the control group (CM, n=8) and male offspring from HF group (HFM, n=9) were given HFD for 4 weeks until sacrifice at 8 weeks of age.The experimental data were analyzed by t test between two groups. Results Compared with CM group, 4 weeks HFD resulted in a significantly increase in HFM in body weight 3.27% (t=-3.924, P<0.01), fat pad mass[(2.26±0.24)% vs (3.67±0.52)%, t=-3.906, P<0.01] and impaired glucose tolerance. Blood glucose in 15 min were (328±26) vs (410±53) mg/dl, 30 min were (318±43) vs (412±48) mg/dl, 60 min were (248±31) vs (328±32) mg/dl and area under the curve were (374±39) mg/dl×120 min vs (388±33) mg/dl×120 min (t=-2.291, -3.656, -4.759, -4.753, all P<0.01). Meanwhile, paternal HFD can increase the HFD-induced methylation of the Pgc-1α promoter were (36.8±4.7)% vs (44.3±3.6)% (t=-4.453, P<0.01) with a trend of decreased Pgc-1α mRNA expression in skeletal muscle. Conclusions The current study provides the evidence that paternal obesity can increase susceptibility to HFD-induced obesity and glucose tolerance dysfunction in male offspring with hypermethylation of the Pgc-1α promoter at CpG site-260. Key words: Paternalobesity; Male pup; Metabolic healthy; Peroxisome proliferator-activated receptor gamma coactivator 1-alpha; DNA methylation

Effect and possible mechanisms of dioscin on ameliorating metabolic glycolipid metabolic disorder in type-2-diabetes

The prevalence of obesity is increasing rapidly worldwide, and dietary intake is strongly associated with obesity-related chronic diseases. However, key metabolic perturbations in obese young men with hyperlipidemia after high-fat diet (HFD) intervention are not yet clear, and remain to be determined. The aim of this study was to investigate the effects of a short-term HFD on glycolipid metabolism, insulin resistance (IR), and urinary metabolomic profiling in young obese men with hyperlipidemia. Sixty young men (19-25 years; 30 normal weight, 30 obese with hyperlipidemia) were enrolled in the study. Differences in metabolomic profiling of urine between normal-weight and obese young men before and after 3 days intake of the HFD were investigated using ultra-HPLC-quadrupole time-of-flight mass spectrometry. After the HFD intervention, total cholesterol (TC), low-density lipoprotein cholesterol, fasting plasma glucose, insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) were significantly increased and high-density lipoprotein cholesterol was significantly decreased in obese men, but only TC was significantly increased in normal-weight subjects. Based on metabolic differences, normal-weight and obese men, and obese men before and after the HFD intervention could be separated into distinct clusters. Seventeen major metabolites were identified that were associated with type 2 diabetes mellitus, glycolipid metabolism and IR; the changes in these metabolites suggest metabolic changes in young obese males after short-term HFD intake. The findings of this study may contribute to increased understanding of the early biological adaptations of obesity with hyperlipidemia to HFD for the early prevention and control of diabetes and IR.

Obesity and related comorbidities are becoming increasingly prevalent globally. In mice preconception paternal exposure to a high fat diet (HFD) impairs the metabolic and reproductive health of male offspring, despite their control diet (CD) consumption. However, offspring share lifestyle, including diet, with parents. We assessed if male offspring from HFD fathers have a heightened susceptibility to HFD-induced metabolic and reproductive derangements. This 2 × 2 design saw founder males (F0) and their offspring (F1) fed either a HFD or a nutritionally matched CD. Regardless of paternal diet, HFD fed male offspring had greater total body weight and adiposity. Offspring sired by a HFD male and fed a HFD were the heaviest, had the greatest adiposity and had the greatest concentration of serum cholesterol, triglyceride, HDL, and NEFA compared with CD sired/fed littermates. A synergistic increase in serum insulin was unmasked by both father/son HFD consumption, concomitant with increased sera glucose. Either a paternal or offspring HFD was associated with similar reductions to offspring sperm motility. Whereas sperm ROS concentrations and sperm–oocyte binding saw detrimental effects of both F0 HFD and F1 HFD with an interaction evident between both, culminating in the most impaired sperm parameters in this group. This indicates that metabolic and fertility disturbances in male offspring sired by HFD fathers are exacerbated by a “second-hit” of exposure to the same obesogenic environment postnatally. If translatable to human health, this suggests that adverse reproductive and metabolic outcomes may be amplified across generations through a shared calorie dense diet, relevant to the current worldwide obesity epidemic.

Hypoglycemic effect and the mechanism of action of a polysaccharide from sweet corncob in a high-fat diet and streptozotocin-induced diabetic mice

IntroductionType 2 diabetes (T2D) is a chronic condition characterized by high levels of blood glucose resulting from the inefficiency of insulin. This study aims to explore the mechanism of TGFB-induced...

Paternal High Fat Diet and Exercise Differentially Regulate Placental Development and Inflammation in a Sex-Specific Manner in C57BL6/J Mice (P19-003-19)

ObjectivePaternal eating and physical activity behaviors peri‐conception may influence offspring obesity and type 2 diabetes (T2D) risk. A recent study showed that paternal exercise increased offspring susceptibility to obesity when the offspring consumed a high fat (HF) diet. However, it is not yet known how paternal HF diet and paternal exercise interact to alter offspring adiposity and T2D risk.MethodThree week old male C57BL/6J mice were fed a control normal fat (NF) diet (16% fat) or a HF diet (45% fat) and provided voluntary wheel running exercise or cage activity (sedentary) for 3 months prior to mating with NF diet‐fed dams. After weaning, male offspring were fed NF or HF diet for 3 months.ResultsCompared to offspring born from cage‐active fathers fed a NF diet, offspring of cage‐active fathers fed a HF diet had decreased body weights at postnatal days 5, 12, and 21 as well as increased insulin resistance at 5 months of age. Paternal HF diet‐induced changes in offspring body weights early in post‐natal life and insulin resistance in adulthood were abolished when fathers exercised. In addition, paternal exercise prevented postnatal HF diet‐induced body and adipose tissue weight increases in offspring at 5 months of age, but only when fathers were fed NF diets.ConclusionThese findings suggest that paternal exercise reduces risk for adiposity and insulin resistance in offspring exposed to a HF diet, but only when fathers consumed a NF diet and exercised. A paternal NF diet alone, without paternal exercise, did not protect HF diet‐induced body and adipose tissue weight gains in offspring. Future studies will determine physiological mechanisms underlying beneficial effects of combined exercise and diet through paternal lineage.Support or Funding InformationThis work was supported by USDA Agricultural Research Service Project #3062‐51000‐052‐00D.

Dysbiosis of gut microbiota can contribute to the progression of diabetes and obesity. Previous studies have shown that maternal high-fat (HF) diet during the perinatal period can alter the microbiota and induce metabolic disorders at weaning. However, whether dysbiosis of gut microbiota and metabolism could be recovered by a normal diet after weaning and the dynamic changes of gut microbiota have not been fully studied. In this study, C57BL/6J female mice were fed with a normal chow (NC) or HF diet for 4 weeks preconception, during gestation, and until pup weaning. After weaning, male offspring were fed with an NC diet until 9 weeks of age. The microbiota of offspring at weaning and 9 weeks of age was collected for 16S rRNA gene amplicon sequencing. We found that dams fed with an HF diet showed glucose intolerance after lactation. Compared with the offspring from NC dams, the offspring from HF dams exhibited a higher body weight, hyperglycemia, glucose intolerance, hyperinsulinemia, hypercholesterolemia, and leptin resistance and lower adiponectin at weaning. Fecal analysis indicated altered microbiota composition between the offspring of the two groups. The decrease in favorable bacteria (such as norank f Bacteroidales S24-7 group) and increase in unfavorable bacteria (such as Lachnoclostridium and Desulfovibrio) were strongly associated with a disturbance of glucose and lipid metabolism. After 6 weeks of normal diet, no difference in body weight, glucose, and lipid profiles was observed between the offspring of the two groups. However, the microbiota composition of offspring in the HF group was still different from that in the NC group, and microbiota diversity was lower in offspring of the HF group. The abundance of Lactobacillus was lower in the offspring of the HF group. In conclusion, a maternal HF diet can induce metabolic homeostasis and gut microbiota disturbance in offspring at weaning. Gut microbiota dysbiosis can persist into adulthood in the offspring, which might have a role in the promotion of susceptibility to obesity and diabetes in the later life of the offspring.

Objective As an adipokine and inflammatory cytokines, chemerin plays an vital role in the occurrence and severity of obesity and its related disease such as atherosclerosis (AS), type 2 diabetes and coronary artery disease, among which the regulation of chemerin on glycolipid metabolism is of great important. Chemerin exerts its main biological functions through binding to its receptor: G protein-coupled receptor chemokine-like receptor (CMKLR1). Chemerin/CMKLR1 has become potential targets for diabetes treatment. For AS, the serum level of chemerin is also related to the disorders of glycolipid metabolism as well as the size and fibrous cap maturity of AS plaques. Exercise decreased the serum level of chemerin in AS, accompanied with the improvement of glucose and lipid metabolism, which indicated the possible relation between decrease of chemerin and improvement of glycolipid metabolism. However, it is still unclear whether exercise-induced improvements of glycolipid metabolism is associated with the changes of chemerin and CMKLR1 in tissue such as livers and gastrocnemius (play key roles in the modulation of glycolipid metabolism) and the mechanism by which chemerin/CMKLR1 modulated glycolipid metabolism. Recent studies reported that chemerin is a target gene of nuclear transcription factor- peroxisome proliferator activated receptor γ (PPARγ). PPARγ links glycolipid metabolism and inflammation through its target gene-adipose triglyceride lipase (ATGL) and lipoprotein lipase (LPL), gate-keeping enzymes hydrolyzing lipids in intracellular triglyceride and plasma lipoproteins respectively. Our previous work has found that aerobic exercise decreased the level of chemerin/CMKLR1 in serum and tissues of type 2 diabetes rats by the mediation of PPARγ-ATGL and LPL. So the purposes of this study were to clarify if exercise-modulated improvement of glycolipid metabolism of atherosclerosis rats was also associated with the changes of chemerin and CMKLR1 in serum and tissues (liver and gastrocnemius), similar as in diabetes, and further its mechanisms. &#x0D; Methods Twenty-seven male Sprague-Dawley (SD) rats aged 6 weeks were randomly divided into control group (Con, n=9) and atherosclerosis (AS, n=18) model rats. AS model rats were established by intraperitoneal injection of Vitamin D3 (600,000 IU/kg body weight in the first week, 100,000 IU/kg body weight in the third week and six week) in combination with 8-week high fat diet feeding. For verifying the successful establishment of AS rats, one rat from Con group and two rats from AS model group were taken randomly to determine the levels of blood glucose and lipid as well as the morphological and pathological alterations of the aorta. Then, 16 successfully established AS rats were randomly divided into AS group (n=8) and exercised AS group (EAS, n=8). EAS group rats experience 4-week moderate intensity aerobic exercise on treadmill with gradually increasing intensity, while the Con and AS rats were kept sedentary life, with all of the rats were fed with common diet during the experiments. Before and after 4-week exercise, the blood sample of the three group rats were drawn to measure the circulating levels of fasting blood glucose (FBG), triglyceride (TC), total cholesterol (TG), LDL and HDL. The serum fasting insulin (FINS) and serum chemerin were measured by ELISA. The protein levels of chemerin, CMKLR1, PPARγ, ATGL and LPL in livers and gastrocnemius were detected by Western blot. And the full-length aorta of the rats were separated to determine AS arteriosclerosis plaques with oil red O staining and histopathological examination with HE staining.&#x0D; &#x0D; Results 1) Compared with AS rats, the disorder of glycolipid metabolism (reflected&#x0D; by increases in TC, TG, LDL and FINS as well as decrease in HDL in blood although no difference in serum level of FBG) were all improved in EAS rats. 2) Compared with AS rats, the atherosclerotic plaque in the aoras and the enhanced proliferation and arrangement disorder of smooth muscle cells in aorta membrane were all alleviated in EAS rats. 3) Compared with AS rats, the increased chemerin in serum and the enhancements of chemerin and CMKLR1 in liver and gastrocnemius at protein levels were all significantly decreased in EAS rats. 4) Compared with AS rats, the protein levels of PPARγ, ATGL and LPL in the livers and gastrocnemius were all increased in EAS rats.&#x0D; Conclusions This study verified that: 1) the exercise-induced improvement of glycolipid metabolism in AS rats was likely to be associated with the decreases of chemerin in serum as well as of chemerin and CMKLR1 in tissues (liver and gastrocnemius). To our knowledge, it is the first report that exercise down-regulated chemerin/CMKLR1 in tissues in AS rats, and the decreases of chemerin/CMKLR1 might be related to the improvement of glycolipid metabolism in AS rats. 2) the exercise-induced decreases of chemerin/CMKLR1 in AS rats might be mediated by PPARγ and its target genes- ATGL and LPL, which need further investigations.

The genomic bases of the adipose tissue abnormalities induced by chronic positive calorie excess have been only partially elucidated. We adopted a genome-wide approach to directly test whether long-term high-fat diet (HFD) exposure affects the DNA methylation profile of the mouse adipose tissue and to identify the functional consequences of these changes. We have used epididymal fat of mice fed either high-fat (HFD) or regular chow (STD) diet for 5 months and performed genome-wide DNA methylation analyses by methylated DNA immunoprecipitation sequencing (MeDIP-seq). Mouse Homeobox (Hox) Gene DNA Methylation PCR, RT-qPCR and bisulphite sequencing analyses were then performed. Mice fed the HFD progressively expanded their adipose mass accompanied by a significant decrease in glucose tolerance (P<0.001) and insulin sensitivity (P<0.05). MeDIP-seq data analysis revealed a uniform distribution of differentially methylated regions (DMR) through the entire adipocyte genome, with a higher number of hypermethylated regions in HFD mice (P<0.005). This different methylation profile was accompanied by increased expression of the Dnmt3a DNA methyltransferase (Dnmt; P<0.05) and the methyl-CpG-binding domain protein Mbd3 (P<0.05) genes in HFD mice. Gene ontology analysis revealed that, in the HFD-treated mice, the Hox family of development genes was highly enriched in differentially methylated genes (P=0.008). To validate this finding, Hoxa5, which is implicated in fat tissue differentiation and remodeling, has been selected and analyzed by bisulphite sequencing, confirming hypermethylation in the adipose tissue from the HFD mice. Hoxa5 hypermethylation was associated with downregulation of Hoxa5 mRNA and protein expression. Feeding animals previously exposed to the HFD with a standard chow diet for two further months improved the metabolic phenotype of the animals, accompanied by return of Hoxa5 methylation and expression levels (P<0.05) to values similar to those of the control mice maintained under standard chow. HFD induces adipose tissue abnormalities accompanied by epigenetic changes at the Hoxa5 adipose tissue remodeling gene.

Paternal High Fat Diet and Exercise Regulate Sperm miRNA to Alter Placental Inflammation and Nutrient Transporter Expression in a Sex-Dependent Manner