High Fat/High Glucose Diet Induces Metabolic Syndrome in an Experimental Rat Model

Traceability of chemicals from Tripterygium Wilfordii Hook. f. in raw honey and the potential synergistic effects of honey on acute toxicity induced by celastrol and triptolide

The object of this study was to trace TwHf-derived toxins in raw honey and clarify their acute toxic effect related to the addition of honey or sugars. TwHf flowers, raw honey from TwHf planting base and from beekeepers in high-risk area were detected using LC-MS/MS. The results revealed five target toxins were detected in TwHf flowers; only celastrol was detected in one raw honey sample, as a food safety risk factor, celastrol had been traced back to TwHf flowers from raw honey. In a series of acute toxic tests on zebrafish, toxification effects were observed when honey, mimic honey or sugar was mixed with toxins. The degree of toxicity varied among various sugar-based solutions. At the same mass concentration, they follow this order: raw honey/mimic honey > glucose > fructose. The main toxic target organs of triptolide and celastrol with honey were the heart and liver.

Behaviour of Tunisian Psammomys obesus fed high-calorie diets: biochemical disturbance and histopathological alterations

This work investigated the biochemical disturbances and histological alteration in Psammomys obesus animal model fed different high calorie diets (HCDs) during three months. Four diets were used: a low-calorie natural diet, Chenopodiaceae halophyte plant used as control (LCD), a high standard carbohydrate diet rich in protein, HCD 0, a high carbohydrate diet rich in two concentrations of fat, HCD 1 and HCD 2. All animals having received HCDs developed dyslipidemia after one month of experiment with distinction of different sub-groups developing or not obesity and diabetes. HCDs induced a remarkable increasing in blood cholesterol, LDL-cholesterol and triglyceride levels indicating a fast induction of dyslipidemia and a significant increase of aminotransaminases activities revealing a pronounced hepatotoxicity. Animal developing diabetes showed a severe hepatic injury, a degeneration of the adipose tissue and a significant reduction of retinal thickness. P. obesus seems to be an excellent animal model to investigate nutritional metabolic diseases.

Anti-obesity effects of Celosia cristata flower extract in vitro and in vivo

BACKGROUND

The overstoring of surplus calories in mature adipocytes causes obesity and abnormal metabolic activity. The anti-obesity effect of a Celosia cristata (CC) total flower extract was assessed in vitro, using 3T3-L1 pre-adipocytes and mouse adipose-derived stem cells (ADSCs), and in vivo, using high-fat diet (HFD)-treated C57BL/6 male mice.

METHODS

CC extract was co-incubated during adipogenesis in both 3T3-L1 cells and ADSCs. After differentiation, lipid droplets were assessed by oil red O staining, adipogenesis and lipolytic factors were evaluated, and intracellular triglyceride and glycerol concentrations were analyzed. For in vivo experiments, histomorphological analysis, mRNA expression levels of adipogenic and lipolytic factors in adipose tissue, blood plasma analysis, metabolic profiles were investigated.

RESULTS

CC treatment significantly prevented adipocyte differentiation and lipid droplet accumulation, reducing adipogenesis-related factors and increasing lipolysis-related factors. Consequently, the intracellular triacylglycerol content was diminished, whereas the glycerol concentration in the cell supernatant increased. Mice fed an HFD supplemented with the CC extract exhibited decreased HFD-induced weight gain with metabolic abnormalities such as intrahepatic lipid accumulation and adipocyte hypertrophy. Improved glucose utilization and insulin sensitivity were observed, accompanied by the amelioration of metabolic disturbances, including alterations in liver enzymes and lipid profiles, in CC-treated mice. Moreover, the CC extract helped restore the disrupted energy metabolism induced by the HFD, based on a metabolic animal monitoring system.

CONCLUSION

This study suggests that CC total flower extract is a potential natural herbal supplement for the prevention and management of obesity.

Ultra-processed food consumption and increased risk of metabolic syndrome in Korean adults: A cross-sectional analysis of the KNHANES 2016-2020

OBJECTIVE

This study aimed to investigate the association between ultra-processed food (UPF) intake and the risk for metabolic syndrome (MetS) in Korean adults.

METHODS

The study consisted of 22 688 Korean adults ≥19 y of age from the Korea National Health and Nutrition Examination Survey (KNHANES) 2016-2020. The NOVA classification categorizes foods according to the nature, extent, and purpose of industrial processing. MetS was defined based on the National Cholesterol Education Program Adult Treatment Panel III criteria and a modified waist circumference cut-off for Korean adults. We estimated the usual percent total food intake from UPFs. We used multivariate logistic regression to assess the association between UPFs and risk for MetS, adjusted for age, sex, education level, income level, smoking status, alcohol drinking, physical activity, and total energy intake. We further analyzed the association of UPFs with each component of MetS.

RESULTS

The median usual percent total food intake from UPFs was 22%, and the midpoint of intake ranged from 3% (quartile 1) to 48% (quartile 4). The group with the highest UPF consumption had a 19% higher risk for developing MetS than the lowest quartile of UPF consumption (odds ratio [OR],1.19; 95% confidence interval [CI], 1.06-1.33; Ptrend = 0.006). In analysis of the relationship between UPF intake and MetS components, a higher UPF was associated with an increased risk for hypertension (OR, 1.13; 95% CI, 1.01-1.26; Ptrend = 0.037) and abdominal obesity (OR, 1.19; 95% CI, 1.07-1.33; Ptrend = 0.001), but had no significant association with other components (hyperglycemia, hypertriacylglycerolmia, and low high-density lipoprotein cholesterol, all P > 0.05).

CONCLUSION

Higher UPF contribution to total daily food intake is associated with an increased risk for MetS, particularly with a higher risk for hypertension and abdominal obesity.

The Influence of a High-Cholesterol Diet and Forced Training on Lipid Metabolism and Intestinal Microbiota in Male Wistar Rats

Adequate experimental animal models play an important role in an objective assessment of the effectiveness of medicines and functional foods enriched with biologically active substances. The aim of our study was a comparative assessment of the effect of consumption of 1 or 2% cholesterol with and without regular (two times a week), moderate running exercise on the main biomarkers of lipid and cholesterol metabolism, as well as the intestinal microbiota of male Wistar rats. In experimental rats, a response of 39 indicators (body weight, food consumption, serum biomarkers, liver composition, and changes in intestinal microbiota) was revealed. Total serum cholesterol level increased 1.8 times in animals consuming cholesterol with a simultaneous increase in low-density lipoprotein cholesterol (2 times) and decrease in high-density lipoprotein cholesterol (1.3 times) levels compared to the control animals. These animals had 1.3 times increased liver weight, almost 5 times increased triglycerides level, and more than 6 times increased cholesterol content. There was a tendency towards a decrease in triglycerides levels against the background of running exercise. The consumption of cholesterol led to a predominance of the Bacteroides family, due to a decrease in F. prausnitzii (1.2 times) and bifidobacteria (1.3 times), as well as an increase in Escherichia family (1.2 times). The running exercise did not lead to the complete normalization of microbiota.

Analysis of Inflammatory Markers in Response to Induction of Reprometabolic Syndrome by a Eucaloric High Fat Diet in Normal Weight Women

Obesity is associated with chronic low-level inflammation and is known to contribute to metabolic dysfunction and hypogonadotropic hypogonadism, which we have previously termed the 'Reprometabolic Syndrome.' To investigate potential factors involved in obesity-related reproductive endocrine dysfunction, we conducted a secondary analysis of inflammatory markers in a sample of normal weight women exposed to a one-month eucaloric high-fat diet (HFD), which, as reported earlier, induced the relative hypogonadotropic hypogonadism characteristic of Reprometabolic Syndrome. Eighteen healthy women with a BMI between 18.0-24.9 kg/m2 and regular menstrual cycles participated in the study. Frequent blood sampling was performed during the early follicular phase before and after the one-month eucaloric HFD intervention (48% of calories from fat). Serum samples pooled from each participant were analyzed using immunoassay to measure levels of 30 cytokines, interleukins, and chemokines. Differences between pre- and post-HFD intervention measures were examined by one-sample t-tests. Exposure to the eucaloric HFD did not result in changes in body weight. HFD-induction of Reprometabolic Syndrome in normal weight women was associated with a significant elevation only in the anti- inflammatory cytokine IL-10 (p = 0.04). Eotaxin, IL-6 and MIP-1β also increased in response to the HFD, but not statistically significantly (p = 0.07). Results suggest that the increase in multiple inflammatory markers, typically associated with obesity, are not primary mediators of the relative hypogonadotropic hypogonadism of Reprometabolic Syndrome. Clinical Trials Registration Number: NCT02653092; Date of Registration: January 6, 2016.

JAK/STAT Inhibition Normalizes Lipid Composition in 3D Human Epidermal Equivalents Challenged with Th2 Cytokines

Derangement of the epidermal barrier lipids and dysregulated immune responses are key pathogenic features of atopic dermatitis (AD). The Th2-type cytokines interleukin IL-4 and IL-13 play a prominent role in AD by activating the Janus Kinase/Signal Transduction and Activator of Transcription (JAK/STAT) intracellular signaling axis. This study aimed to investigate the role of JAK/STAT in the lipid perturbations induced by Th2 signaling in 3D epidermal equivalents. Tofacitinib, a low-molecular-mass JAK inhibitor, was used to screen for JAK/STAT-mediated deregulation of lipid metabolism. Th2 cytokines decreased the expression of elongases 1, 3, and 4 and serine-palmitoyl-transferase and increased that of sphingolipid delta(4)-desaturase and carbonic anhydrase 2. Th2 cytokines inhibited the synthesis of palmitoleic acid and caused depletion of triglycerides, in association with altered phosphatidylcholine profiles and fatty acid (FA) metabolism. Overall, the ceramide profiles were minimally affected. Except for most sphingolipids and very-long-chain FAs, the effects of Th2 on lipid pathways were reversed by co-treatment with tofacitinib. An increase in the mRNA levels of CPT1A and ACAT1, reduced by tofacitinib, suggests that Th2 cytokines promote FA beta-oxidation. In conclusion, pharmacological inhibition of JAK/STAT activation prevents the lipid disruption caused by the halted homeostasis of FA metabolism.

Very low-carbohydrate diet with higher protein ratio improves lipid metabolism and inflammation in rats with diet-induced nonalcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is commonly associated with obesity, and it is mainly treated through lifestyle modifications. The very low-carbohydrate diet (VLCD) can help lose weight rapidly but the possible effects of extreme dietary patterns on lipid metabolism and inflammatory responses in individuals with NAFLD remain debatable. Moreover, VLCD protein content may affect its effectiveness in weight loss, steatosis, and inflammatory responses. Therefore, we investigated the effects of VLCDs with different protein contents in NAFLD rats and the mechanisms underlying these effects. After a 16-week inducing period, the rats received an isocaloric normal diet (NC group) or a VLCD with high or low protein content (NVLH vs. NVLL group, energy ratio:protein/carbohydrate/lipid=20/1/79 vs. 6/1/93) for the next 8 weeks experimental period. We noted that the body weight decreased in both the NVLH and NVLL groups; nevertheless, the NVLH group demonstrated improvements in ketosis. The NVLL group led to hepatic lipid accumulation, possibly by increasing very-low-density lipoprotein receptor (VLDLR) expression and elevating liver oxidative stress, subsequently activating the expression of Nrf2, and inflammation through the TLR4/TRIF/NLRP3 and TLR4/MyD88/NF-κB pathway. The NVLH was noted to prevent the changes in VLDLR and the TLR4-inflammasome pathway partially. The VLCD also reduced the diversity of gut microbiota and changed their composition. In conclusion, although low-protein VLCD consumption reduces BW, it may also lead to metabolic disorders and changes in microbiota composition; nevertheless, a VLCD with high protein content may partially alleviate these limitations.

Influence of Chronic Forced Immobilization and Consumption of a High-Fat and High-Carbohydrate Diet Containing Cholesterol on Lipid and Cholesterol Metabolism in Male Wistar Rats

We studied the effect of separate and combined influence of chronic forced physical activity reduction and high-fat and high-carbohydrate diet containing cholesterol on some indicators of carbohydrate, lipid, and cholesterol metabolism in growing male Wistar rats. Used combination of factors simulating a sedentary lifestyle and unhealthy diet did not have a synergistic effect on the selected biomarkers. On the contrary, the effect was antagonistic: body weight and appetite decreased and insulin resistance increased. The obtained results indicate certain prospects of hypercholesterolemia model using in preclinical studies of specialized food products to optimize the diet of individuals with disorders of carbohydrate and lipid metabolism.

Empowering mitochondrial metabolism: Exploring L-lactate supplementation as a promising therapeutic approach for metabolic syndrome

Mitochondrial dysfunction plays a critical role in the pathogenesis of metabolic syndrome (MetS), affecting various cell types and organs. In MetS animal models, mitochondria exhibit decreased quality control, characterized by abnormal morphological structure, impaired metabolic activity, reduced energy production, disrupted signaling cascades, and oxidative stress. The aberrant changes in mitochondrial function exacerbate the progression of metabolic syndrome, setting in motion a pernicious cycle. From this perspective, reversing mitochondrial dysfunction is likely to become a novel and powerful approach for treating MetS. Unfortunately, there are currently no effective drugs available in clinical practice to improve mitochondrial function. Recently, L-lactate has garnered significant attention as a valuable metabolite due to its ability to regulate mitochondrial metabolic processes and function. It is highly likely that treating MetS and its related complications can be achieved by correcting mitochondrial homeostasis disorders. In this review, we comprehensively discuss the complex relationship between mitochondrial function and MetS and the involvement of L-lactate in regulating mitochondrial metabolism and associated signaling pathways. Furthermore, it highlights recent findings on the involvement of L-lactate in common pathologies of MetS and explores its potential clinical application and further prospects, thus providing new insights into treatment possibilities for MetS.

Common risk factors for dental caries and impaired glucose regulation in Guangxi, China

OBJECTIVES

To assess the prevalence of caries and impaired glucose regulation (IGR) and try to investigate their common risk factors among adult residents in Guangxi province.

METHODS

A cross-sectional study was conducted on a sample of 2993 adults from five different areas of Guangxi province. The sociodemographic data, history of personal habits such as diet and physical activities, physical measurements, oral examination results and biochemical laboratory test data were collected to establish a database and prepare a sound research model. Chi-square test and multiple logistic regression were used to analyse the risk factors for dental caries and IGR.

RESULTS

The prevalence rate for caries was 85.9%, and the mean DMFT score was 7.35. In multiple logistic regression, after adjustment, education level, occupation, daily consumption of vegetables, weekly consumption of carbonated beverages and weekly exercise were associated with caries (odds ratio [OR]: 2.10, OR: 1.80, OR: 1.40, OR: 2.45, OR: 2.38). The prevalence of IGR was 33.5%, and after adjustment, results showed that occupation, body mass index, waist circumference, systolic blood pressure, diastolic blood pressure, high-density lipoprotein-C levels and low-density lipoprotein-C levels were significantly associated with IGR (OR: 0.80, OR: 1.70, OR: 1.56, OR: 1.88, OR: 1.60, OR: 1.43, OR: 1.48). The strength of association between caries/IGR and risk factors was a weak association or moderate association.

CONCLUSIONS

We have not found common risk factors between dental caries and IGR. Therefore, further studies are needed to explore these common risk factors to prevent caries and IGR.

High-Fat Diets in Animal Models of Alzheimer's Disease: How Can Eating Too Much Fat Increase Alzheimer's Disease Risk?

High dietary intake of saturated fatty acids is a suspected risk factor for neurodegenerative diseases, including Alzheimer's disease (AD). To decipher the causal link behind these associations, high-fat diets (HFD) have been repeatedly investigated in animal models. Preclinical studies allow full control over dietary composition, avoiding ethical concerns in clinical trials. The goal of the present article is to provide a narrative review of reports on HFD in animal models of AD. Eligibility criteria included mouse models of AD fed a HFD defined as > 35% of fat/weight and western diets containing > 1% cholesterol or > 15% sugar. MEDLINE and Embase databases were searched from 1946 to August 2022, and 32 preclinical studies were included in the review. HFD-induced obesity and metabolic disturbances such as insulin resistance and glucose intolerance have been replicated in most studies, but with methodological variability. Most studies have found an aggravating effect of HFD on brain Aβ pathology, whereas tau pathology has been much less studied, and results are more equivocal. While most reports show HFD-induced impairment on cognitive behavior, confounding factors may blur their interpretation. In summary, despite conflicting results, exposing rodents to diets highly enriched in saturated fat induces not only metabolic defects, but also cognitive impairment often accompanied by aggravated neuropathological markers, most notably Aβ burden. Although there are important variations between methods, particularly the lack of diet characterization, these studies collectively suggest that excessive intake of saturated fat should be avoided in order to lower the incidence of AD.

Design, synthesis, and biological evaluation of deuterated indolepropionic acid derivatives as novel long-acting pan PPARα/γ/δ agonists

Metabolic syndrome is a complex disease with diverse symptoms, but current pharmacological interventions have limited efficacy. Indeglitazar, a pan-agonist targeting the three-peroxisome proliferator activated receptors (PPAR), exhibits significant therapeutic effects on both diabetic and fatty liver animal models. However, its short half-life limits the in vivo efficacy, which might be attributed to the β-oxidation of indolepropionic acid at Indeglitazar. To overcome this metabolic instability, two deuterium atoms were introduced to the α-position of indolepropionic acid to block the β-oxidation. In this study, several deuterated derivatives were found to sustain PPARs activity and extend the half-life of liver microsomes. In oral glucose tolerance tests, I-1 exhibited the strongest glucose-lowering effect on ob/ob mice in this series. In db/db mice, I-1 reduced lipid levels, liver steatosis and promoted UCP1 expression in white adipose tissue. Mechanistic studies further revealed that I-1 exerts stronger effects than Indeglitazar on the regulation of genes related to lipid metabolism, mitochondrial function, and oxidative stress. Furthermore, I-1 significantly reduced liver steatosis, hepatocellular ballooning, inflammation, and fibrosis in NASH model induced by HFD + CCl4, and even exerted better therapeutic effect than that of Indeglitazar. With the above attractive efficacy, deuterated derivative I-1 is considered as a promising treatment for metabolic syndrome.

The effects of 20-hydroxyecdysone on nuclear shape, heterochromatin quantity and gray-level co-occurrence matrix texture analysis of adrenal zona fasciculata cells in an obese gerbil (Gerbillus tarabuli) model for metabolic syndrome: a correlational study

The aim of this study was to reveal the effects of obesity and phytotherapy with 20-hydroxyecdysone (20E) on the nuclei of adrenal zona fasciculata (ZF) in the gerbil Gerbillus tarabuli by analyzing nuclear shape and gray-level co-occurrence matrix (GLCM) texture characteristics and by quantifying heterochromatin. Twelve gerbils were divided into three groups: control (C), HC and HC-20E (animals receiving a high-calorie-diet without or with a supplement of 20E, respectively). The adrenals were removed and fixed for histological and statistical analysis. Principal component analysis showed a positive correlation of area, perimeter and textural correlation in C. Nevertheless, a negative correlation was recorded for contrast and entropy. The obesity caused a disorder in nuclear texture; negative correlation was noted with heterochromatin fraction, which may be related to increased ZF activity. However, administration of 20E seems to improve the nuclear state by preserving circularity, uniformity and homogeneity of nuclei as well as the proportion of heterochromatin, which could be a sign of a downregulation of cell activity.Our results suggest that new techniques of image processing could contribute to the understanding of nuclear changes associated with obesity and its possible therapy in this gerbil model for metabolic syndrome.

Toward Systems-Level Metabolic Analysis in Endocrine Disorders and Cancer

Metabolism is a dynamic network of biochemical reactions that support systemic homeostasis amidst changing nutritional, environmental, and physical activity factors. The circulatory system facilitates metabolite exchange among organs, while the endocrine system finely tunes metabolism through hormone release. Endocrine disorders like obesity, diabetes, and Cushing's syndrome disrupt this balance, contributing to systemic inflammation and global health burdens. They accompany metabolic changes on multiple levels from molecular interactions to individual organs to the whole body. Understanding how metabolic fluxes relate to endocrine disorders illuminates the underlying dysregulation. Cancer is increasingly considered a systemic disorder because it not only affects cells in localized tumors but also the whole body, especially in metastasis. In tumorigenesis, cancer-specific mutations and nutrient availability in the tumor microenvironment reprogram cellular metabolism to meet increased energy and biosynthesis needs. Cancer cachexia results in metabolic changes to other organs like muscle, adipose tissue, and liver. This review explores the interplay between the endocrine system and systems-level metabolism in health and disease. We highlight metabolic fluxes in conditions like obesity, diabetes, Cushing's syndrome, and cancers. Recent advances in metabolomics, fluxomics, and systems biology promise new insights into dynamic metabolism, offering potential biomarkers, therapeutic targets, and personalized medicine.

Rat models of diet-induced obesity and metabolic dysregulation: Current trends, shortcomings and considerations for future research

Rat diet-induced obesity and metabolic dysregulation (DIO/DIMD) is widely used as a pre-clinical model for human obesity and for testing weight-loss interventions. The aim of this review was to utilise a systematic literature survey of rat DIO/DIMD studies as a tool to document trends around study design and metabolic outcomes of these studies, and to consider ways in which the design of these studies may be improved to enhance the relevance thereof for human obesity research. In total, 110 comparisons between control and obesogenic dietary groups were included in the survey. Young male rats were found to be the model of choice, but fewer than 50% of studies provided comprehensive information about diet composition and energy intake. In addition, it was found that the majority of expected DIO/DIMD responses (hyperglycemia, hyperinsulinemia, dyslipidemia, hypoadiponectinemia) occurred at < 80% frequency, drawing into question the concept of a "typical" or "appropriate" response. We discuss the impact of differences in diet composition and energy intake on metabolic outcomes against the context of large heterogeneity of obesogenic diets employed in rat DIO/DIMD studies, and provide recommendations for the improvement of reporting standards around diet composition and dietary intake. In addition, we highlight the lack of data from female and older rats and describe considerations around the inclusion of sex and age as a variable in rat DIO/DIMD studies, aiming towards improving the applicability of these studies as a model of human obesity, which is most prevalent in women and older individuals.

Combined fructose and sucrose consumption from an early age aggravates cardiac oxidative damage and causes a dilated cardiomyopathy in SHR rats

Obesity increases the risk of arterial hypertension in young adults and favors an early-onset cardiomyopathy by generating oxidative stress. In this sense, indiscriminate consumption of sucrose and fructose sweetened beverages from early ages causes obesity, however its consequences on the heart when there is a genetic predisposition to develop hypertension are not clear. We compared the effects of sucrose, fructose, and their combination in weanling male spontaneously hypertensive rats to determine the relationship between genetic hypertension, obesity, and consumption of these sugars on the degree of cardiac hypertrophy, oxidative stress and Ca2+/calmodulin dependent protein kinase II delta oxidation. Histological, biochemical, and Western blot studies were performed 12 weeks after treatment initiation. We found that chronic consumption of sucrose or fructose leads to obesity, exacerbates genetic arterial hypertension-induced metabolic alterations, and increases cardiac oxidative stress, Ca2+/calmodulin dependent protein kinase II delta oxidation and cardiac hypertrophy. Nonetheless, when sucrose and fructose are consumed together, metabolic alterations worsen and are accompanied by dilated cardiomyopathy. These data suggest that sucrose and fructose combined consumption starting from maternal weaning in rats with genetic predisposition to arterial hypertension accelerates the progression of cardiomyopathy resulting in an early dilated cardiomyopathy.

Metabolic mitochondrial alterations prevail in the female rat heart 8 weeks after exercise cessation

BACKGROUND

The consumption of high-caloric diets strongly contributes to the development of non-communicable diseases (NCDs), including cardiovascular disease, the leading cause of mortality worldwide. Exercise (along with diet intervention) is one of the primary non-pharmacological approaches to promote a healthier lifestyle and counteract the rampant prevalence of NCDs. The present study evaluated the effects of exercise cessation after a short period training on the cardiac metabolic and mitochondrial function of female rats.

METHODS

Seven-week-old female Sprague-Dawley rats were fed a control or a high-fat, high-sugar (HFHS) diet and, after 7 weeks, the animals were kept on a sedentary lifestyle or submitted to endurance exercise for 3 weeks (6 days per week, 20-60 min/day). The cardiac samples were analysed 8 weeks after exercise cessation.

RESULTS

The consumption of the HFHS diet triggered impaired glucose tolerance, whereas the HFHS diet and physical exercise resulted in different responses in plasma adiponectin and leptin levels. Cardiac mitochondrial respiration efficiency was decreased by the HFHS diet consumption, which led to reduced ATP and increased NAD(P)H mitochondrial levels, which remained prevented by exercise 8 weeks after cessation. Exercise training-induced cardiac adaptations in redox balance, namely increased relative expression of Nrf2 and downstream antioxidant enzymes persist after an eight-week exercise cessation period.

CONCLUSIONS

Endurance exercise modulated cardiac redox balance and mitochondrial efficiency in female rats fed a HFHS diet. These findings suggest that exercise may elicit cardiac adaptations crucial for its role as a non-pharmacological intervention for individuals at risk of developing NCDs.

Elderly rats fed with a high-fat high-sucrose diet developed sex-dependent metabolic syndrome regardless of long-term metformin and liraglutide treatment

Aim/Introduction

The study aimed to determine the effectiveness of early antidiabetic therapy in reversing metabolic changes caused by high-fat and high-sucrose diet (HFHSD) in both sexes.

Methods

Elderly Sprague-Dawley rats, 45 weeks old, were randomized into four groups: a control group fed on the standard diet (STD), one group fed the HFHSD, and two groups fed the HFHSD along with long-term treatment of either metformin (HFHSD+M) or liraglutide (HFHSD+L). Antidiabetic treatment started 5 weeks after the introduction of the diet and lasted 13 weeks until the animals were 64 weeks old.

Results

Unexpectedly, HFHSD-fed animals did not gain weight but underwent significant metabolic changes. Both antidiabetic treatments produced sex-specific effects, but neither prevented the onset of prediabetes nor diabetes.

Conclusion

Liraglutide vested benefits to liver and skeletal muscle tissue in males but induced signs of insulin resistance in females.

Benefits of Chronic Administration of a Carbohydrate-Free Diet on Biochemical and Morphometric Parameters in a Rat Model of Diet-Induced Metabolic Syndrome

Carbohydrate intake restriction positively affects markers related to metabolic syndrome (MS). However, the effects of long-term carbohydrate-free diets (CFD) have yet to be studied. The main objective of this study was to report the effects on biochemical and morphometric parameters in a rat model of MS. Male Wistar rats were initially divided into two groups: the standard diet group (SD, n = 20); and the MS group (n = 30) fed a high-glucose diet. Ten animals from each group were sacrificed after 20 weeks on their respective diets to verify MS development. The remaining MS animals were divided into two subgroups: one continued with the MS diet (n = 10); and the other transitioned to a carbohydrate-free diet (MS + CFD group, n = 10) for 20 more weeks. At week 40, parameters, including glucose, insulin, lipid profile, ketone bodies, C-reactive protein (CRP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, creatinine, liver and muscle glycogen, and serum, hepatic, renal, and pancreatic malondialdehyde (MDA) levels were assessed. Transitioning to CFD resulted in decreased caloric intake and body weight, with normalized parameters including MDA, insulin, lipid profile, ALT, liver glycogen, creatinine, and CRP levels. This shift effectively reversed the MS-induced alterations, except for glycemia and uremia, likely influenced by the diet's high protein content stimulating gluconeogenesis. This research underscores the potential benefits of long-term carbohydrate restriction in mitigating MS-related markers.

Spexin alleviates hypertension, hyperuricaemia, dyslipidemia and insulin resistance in high fructose diet induced metabolic syndrome in rats via enhancing PPAR-ɣ and AMPK and inhibiting IL-6 and TNF-α

Spexin is a novel peptide implicated in obesity and energy homeostasis. The objective of the current study was to evaluate the effect of spexin on blood pressure, insulin resistance, and dyslipidemia in rats with metabolic syndrome (MS) induced by high-fructose diet (HFD) and the possible underlying mechanism. Forty adult male rats were randomly assigned into four equal groups; Control, Spexin, HFD and HFD + spexin. Induction of the MS with HFD was associated with increased body mass index, elevated blood pressure, blood glucose, insulin, uric acid, advanced glycation end products and insulin resistance, interlekin-6, tumour necrosis factor-alpha together with dyslipidemia, low-serum spexin, peroxisome proliferator-activated receptors-gamma (PPAR-ɣ) and adenosine monophosphate-activated protein kinase (AMPK). Spexin attenuated MS-induced deleterious effects which can be attributed to activation of PPAR-ɣ and AMPK as well as inhibiting inflammation. These findings indicate that spexin could be a beneficial complementary agent for metabolic syndrome treatment.

Puberty as a DOHaD programming window: high-fat diet induces long-term hepatic dysfunction in male rats

The aim of this study was to evaluate whether high-fat (HF) diet intake during puberty can program obesity as well as generate glucose imbalance and hepatic metabolic dysfunctions in adult life. Male Wistar rats were randomly assigned into two groups: rats fed standard chow (NF) and rats fed a HF from postnatal 30-day-old (PND30) until PND60. Then, both groups were fed a standard chow from PND60 until PND120. Euthanasia and samples collections occurred at PND120. HF animals were overweight (+11%) and had increased adiposity, hyperphagia (+12%), hyperglycaemia (+13%), hyperinsulinemia (+69%), and hypertriglyceridemia (+34%). Plasma glucose levels during intravenous glucose tolerance test (ivGTT) and intraperitoneal insulin tolerance test (ipITT) were also higher in the HF group, whereas Kitt was significantly lower (-34%), suggesting reduced insulin sensitivity. In the same sense, HF animals present pancreatic islets hypertrophy and high β-cell mass. HF animals also had a significant increase in blood glucose levels during pyruvate tolerance test, indicating increased gluconeogenesis. Hepatic morphology analyses showed an increase in lipid inclusion in the HF group. Moreover, PEPCK and FAS protein expression were higher in the livers of the HF animals (+79% and + 37%, respectively). In conclusion, HF during puberty causes obese phenotype leading to glucose dyshomeostasis and nonalcoholic fatty liver disease, which can be related to the overexpression of proteins PEPCK and FAS.

Micropatterned primary hepatocyte co-culture (HEPATOPAC) for fatty liver disease modeling and drug screening

Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent, progressive disorder and growing public health concern. To address this issue considerable research has been undertaken in pursuit of new NAFLD therapeutics. Development of effective, high-throughput in vitro models is an important aspect of drug discovery. Here, a micropatterned hepatocyte co-culture (MPCC) was used to model liver steatosis. The MPCC model (HEPATOPACTM) is comprised of hepatocytes and 3T3-J2 mouse stromal cells plated onto a patterned standard 96-well or 24-well plate, allowing the cultures to be handled and imaged in a standardized multi-well format. These studies employed high content imaging (HCI) analysis to assess lipid content in cultures. HCI analysis of lipid accumulation allows large numbers of samples to be imaged and analyzed in a relatively short period of time compared to manual acquisition and analysis methods. Treatment of MPCC with free fatty acids (FFA), high glucose and fructose (HGF), or a combination of both induces hepatic steatosis. MPCC treatment with ACC1/ACC2 inhibitors, as either a preventative or reversal agent, showed efficacy against FFA induced hepatic steatosis. Drug induced steatosis was also evaluated. Treatment with valproic acid showed steatosis induction in a lean background, which was significantly potentiated in a fatty liver background. Additionally, these media treatments changed expression of fatty liver related genes. Treatment of MPCC with FFA, HGF, or a combination reversibly altered expression of genes involved in fatty acid metabolism, insulin signaling, and lipid transport. Together, these data demonstrate that MPCC is an easy to use, long-term functional in vitro model of NAFLD having utility for compound screening, drug toxicity evaluation, and assessment of gene regulation.

The assessment of serum trace element levels as the diagnostic biomarkers of functional state of broiler chickens

Background and Aim

Elemental analysis is a useful technique for predicting metabolic disorders in broiler chickens. Elemental imbalances are also important for the development of new methods to diagnose the health status of birds that can be implemented on a farm-wide scale. This study aimed to identify elemental markers related to pre-nosological diagnoses of metabolic disorders in broiler chickens.

Materials and Methods

We compared birds given high-protein, high-carbohydrate, and high-fat diets. A control group received the standard diet recommended by the All-Russian Research and Technological Institute of Poultry, while experimental Group I received a diet with high-protein content, Group II received a diet with high-carbohydrate content, and Group III received a diet with high-fat content. At the end of the experiment, blood samples were taken for biochemical and elemental analysis. Biochemical analysis was carried out using an automated biochemical analyzer, and the levels of trace elements in the serum were assessed using inductively coupled plasma spectrometry.

Results

We found that the high-protein diet was accompanied by a decrease in chicken body weight, cholesterol, and several elements (i.e., P, Cr, Cu, Zn, and B) as well as an increase in the levels of Ca, Co, and Si. The high-carbohydrate diet led to a significant increase in glucose levels as well as a decrease in the levels of albumin, triglycerides, and Cr, Mn, Se, I, and Cu. Finally, the high-fat diet led to an increase in body weight, glucose, cholesterol, triglycerides, and the elements Cu, Zn, and Si as well as a decrease in the levels of Mg, Cr, and Fe.

Conclusion

The determination of the levels of trace elements such as Co, Cr, Mn, Fe, and Cu in chicken blood serum may be an important indicator of the state of protein, carbohydrate, and lipid metabolism of poultry stock.

Hypolipidaemic effects of papaya (Carica papaya L.) juice on rats fed on a high fat and fructose diet

Papaya (Carica papaya L.) is a highly nutritious and less-caloric fruit, commonly consumed for its minerals and vitamins and hence may help in controlling obesity and abdominal discomforts. The present study investigated the hypolipidaemic effects of papaya juice extract on male Albino Wistar rats (7 weeks old; 185 ± 17 g) fed on a high fat and fructose diet (HFFD) for 6 weeks. The rats were divided into groups I-IV of five rats each and fed on either a HFFD (i.e. the Control), HFFD + 200 mg papaya, HFFD + 350 mg papaya or a HFFD + 500 mg papaya. On day 34, after an overnight fast, blood samples were obtained by cardiac puncture under 99⋅8 % Chloroform anaesthesia for the determination of serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c) and high-density cholesterol (HDL-c). The atherogenic (AI) and coronary risk (CRI) indices were also calculated. Statistical analysis was performed using ANOVA where means were separated using Tukey's HSD test. Resulted showed that all rats given papaya juice had an increasing, non-significant HDL-c and reduced LDL-c levels while rats fed on HFFD had the highest TC (53⋅2 mg/dl) and TG (37⋅6 mg/dl) levels. Papaya juice statistically reduced the AI and CRI of the rats. In conclusion, consumption of HFFD + 500 mg was the most effective in the reduction of rats' blood lipids and fats, due to its anti-obesity and hypolipidaemic properties, thus can be used in the management of dyspilidaemic disorders.

Experimental models of fatty liver diseases: Status and appraisal

Fatty liver diseases, including alcohol-associated liver disease (ALD) and nonalcoholic fatty liver disease nonalcoholic fatty liver disease (NAFLD), affect a large number of people worldwide and become one of the major causes of end-stage liver disease, such as liver cirrhosis and hepatocellular carcinoma (HCC). Unfortunately, there are currently no approved pharmacological treatments for ALD or NAFLD. This situation highlights the urgent need to explore new intervention targets and discover effective therapeutics for ALD and NAFLD. The lack of properly validated preclinical disease models is a major obstacle to the development of clinical therapies. ALD and NAFLD models have been in the development for decades, but there are still no models that recapitulate the full spectrum of ALD and NAFLD. Throughout this review, we summarize the current in vitro and in vivo models used for research on fatty liver diseases and discuss the advantages and limitations of these models.

The Effect of Omega-3 Fatty Acids on Insulin Resistance

Insulin resistance is a critical pathophysiological process in the onset and advancement of type 2 diabetes mellitus. It is well-recognized that alterations in the metabolism of lipids and aberrant fat buildup effectively trigger the development of resistance to insulin. Adjusting one's eating habits and managing weight appropriately are crucial for treating, controlling, and reducing the risk of T2DM because obesity and a lack of physical exercise are the primary factors responsible for the worldwide rise in T2DM. Omega-3 fatty acid is one of the polyunsaturated fatty acids (PUFA) that include long-chain omega-3 fatty acids such as eicosapentaenoic acid and docosahexaenoic acid, commonly found in fish oils. Omega-3 and omega-6 polyunsaturated fatty acids (PUFAs; 3 and 6 PUFAs) are essential for human health because they serve as metabolic precursors of eicosanoids, a class of signaling molecules that are essential for controlling a body's inflammation. Since humans are unable to produce any of the omega-3 or omega-6 PUFAs, they both constitute imperative nutritional ingredients. Long-standing concerns about long-chain omega-3 fatty acids' impact on diabetes management have been supported by experimental investigations that found significant increases in fasting glucose following omega-3 fatty acid supplementation and foods rich in PUFA and omega-3 fatty acid. Cellular explanations to explain the connection between inflammation and IR include mitochondrial dysfunction, endoplasmic reticulum (ER) stress, and oxidative stress. Modifications in the lipid composition of mitochondrial membranes and/or receptor-mediated signaling may be part of the mechanism behind the activation of mitochondrial fusion by fish oil/omega-3 PUFA. The exact molecular processes by which omega-3 PUFAs control mitochondrial activity to defend against IR are still unknown.

Gochujang Consumption Prevents Metabolic Syndrome in a High-Fat Diet Induced Obese Mouse Model

High-fat and high-salt diets are risk factors for metabolic syndrome development. However, gochujang, which has a high salt content, possesses antiobesity properties in cell and animal models. We aimed to evaluate the effects of Sunchang traditional and modern factory produced gochujang on metabolic syndrome factors in high-fat diet (HFD)-induced obese mice. For 14 weeks, 4-week-old C57BL/6J male mice were separated into five groups and fed a normal diet (ND), a high-fat diet only (HD), a HD with salt (SALT), a HD with traditional Sunchang gochujang (TS), and HD with modern factory made Sunchang gochujang (FS). Compared to HD and SALT groups, the gochujang groups had lower body weight, blood leptin, and insulin levels with reduced Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) index and improved serum and liver lipid profiles. In addition, gochujang supplemented groups exhibited a significant reduction in mRNA expression of anabolic lipid metabolism related factors; PPARγ, CEBPα, and FABP4, and a significant increase in mRNA expression of energy expenditure-related factors; PPARα and CPT1. Protein expressions of SREBP1 were downregulated in the gochujang fed groups. TS and FS intakes improved obesity in HFD-induced obese mice. Compared to the gochujang groups, the SALT group did not exhibit any of those benefits suggesting that the high salt content of gochujang has different effects compared with added salt alone. Our findings provide evidence that gochujang could be a functional food to attenuate metabolic syndrome.

Outrunning a bad diet: interactions between exercise and a Western-style diet for adolescent mental health, metabolism and microbes

Adolescence is a period of biological, psychological and social changes, and the peak time for the emergence of mental health problems. During this life stage, brain plasticity including hippocampal neurogenesis is increased, which is crucial for cognitive functions and regulation of emotional responses. The hippocampus is especially susceptible to environmental and lifestyle influences, mediated by changes in physiological systems, resulting in enhanced brain plasticity but also an elevated risk for developing mental health problems. Indeed, adolescence is accompanied by increased activation of the maturing hypothalamic-pituitary-adrenal axis, sensitivity to metabolic changes due to increased nutritional needs and hormonal changes, and gut microbiota maturation. Importantly, dietary habits and levels of physical activity significantly impact these systems. In this review, the interactions between exercise and Western-style diets, which are high in fat and sugar, on adolescent stress susceptibility, metabolism and the gut microbiota are explored. We provide an overview of current knowledge on implications of these interactions for hippocampal function and adolescent mental health, and speculate on potential mechanisms which require further investigation.

Yohimbine Alleviates Oxidative Stress and Suppresses Aerobic Cysteine Metabolism Elevated in the Rat Liver of High-Fat Diet-Fed Rats

Yohimbine is a small indole alkaloid derived from the bark of the yohimbe tree with documented biological activity, including anti-inflammatory, erectile dysfunction relieving, and fat-burning properties. Hydrogen sulfide (H₂S) and sulfane sulfur-containing compounds are regarded as important molecules in redox regulation and are involved in many physiological processes. Recently, their role in the pathophysiology of obesity and obesity-induced liver injury was also reported. The aim of the present study was to verify whether the mechanism of biological activity of yohimbine is related to reactive sulfur species formed during cysteine catabolism. We tested the effect of yohimbine at doses of 2 and 5 mg/kg/day administered for 30 days on aerobic and anaerobic catabolism of cysteine and oxidative processes in the liver of high-fat diet (HFD)-induced obese rats. Our study revealed that HFD resulted in a decrease in cysteine and sulfane sulfur levels in the liver, while sulfates were elevated. In the liver of obese rats, rhodanese expression was diminished while lipid peroxidation increased. Yohimbine did not influence sulfane sulfur and thiol levels in the liver of obese rats, however, this alkaloid at a dose of 5 mg decreased sulfates to the control level and induced expression of rhodanese. Moreover, it diminished hepatic lipid peroxidation. It can be concluded that HFD attenuates anaerobic and enhances aerobic cysteine catabolism and induces lipid peroxidation in the rat liver. Yohimbine at a dose of 5 mg/kg can alleviate oxidative stress and reduce elevated concentrations of sulfate probably by the induction of TST expression.

Quercetin ameliorates hepatic fat accumulation in high-fat diet-induced obese mice via PPARs

As a natural pigment in food, quercetin possesses multiple biological activities and plays a crucial role in regulating metabolic syndrome. Herein, we aim to explore the potential mechanism of quercetin to ameliorate hepatic fat accumulation. In vivo experiments showed that quercetin significantly relieved inflammation response by decreasing the serum TNF-α and IL-6 levels and also improved high-fat diet-induced hepatic steatosis without other organ injuries. Quercetin can effectively reduce lipid aggregation and down-regulate the protein expression of PCK1 in HepG2 cells induced by oleic acid and palmitic acid, indicating that inhibiting gluconeogenesis leads to hepatic fat accumulation reduction. Furthermore, molecular docking results suggested that quercetin can bind to both PPARα and PPARγ, with an even more potent binding affinity than indeglitazar, a pan-agonist of PPARs. In conclusion, quercetin may regulate gluconeogenesis to ameliorate hepatic fat accumulation via targeting PPARα/γ.

Excessive sucrose exacerbates high fat diet-induced hepatic inflammation and fibrosis promoting osteoarthritis in mice model

Osteoarthritis (OA) is marked by chronic low-grade systemic inflammation and cartilage destruction. High fat diet causes obesity and increases the risk of knee OA-development. However, the impact of high dietary sugar intake on OA pathogenesis has not been elucidated yet. Therefore, we investigated the effects of a high-fat and high-sucrose (HF+HS) diet in experimental OA mouse models. Eight-week-old male C57BL/6J mice were fed a standard chow (n=6), high-fat (HF) (n=5), or HF+HS (n=7) diets for 12 weeks; thereafter, the mice underwent surgical destabilization of the medial meniscus (DMM) and received the same experimental diets for an additional 8 weeks. The pathogenesis of knee OA, obesogenic parameters, and inflammation levels in the liver and adipose tissue were investigated. HF+HS diet induced severe cartilage erosion with osteophyte development and subchondral bone plate thickening, indicating that HF+HS diet exacerbated OA. Despite marginal differences in metabolic parameters, hepatic free cholesterol accumulation increased in mice with DMM-induced OA fed on HF+HS diet than in those fed HF diet. Notably, the levels of inflammatory cytokines and fibrosis markers were greater in the livers of mice with DMM-induced OA, fed on HF+HS diet than those in the control group. However, adipose tissue remodeling was not affected by the HF+HS diet. These findings indicate that excess sucrose intake along with a HF diet triggers hepatic inflammation and fibrosis, thereby, contributing to OA pathogenesis.

Appetite–regulating hormones in rats with fructose-induced metabolic changes

Objectives: The aim of this research is to examine the effects of fructose-drinking on the plasma levels of appetite-regulating hormones insulin, leptin and ghrelin in male and female rats.

Methods: Mature Wistar rats were divided as follows: two control groups - male (CM) and female (CF); two fructose-drinking groups - male (FDM) and female (FDF), received 15% fructose solution. The experiment lasted 11 weeks. At the end, insulin, leptin and ghrelin levels as well as lipid and glucose profile were assessed.

Results: Plasma concentrations of the examined hormones were elevated in fructose-drinking groups. However, in the FDM group only the leptin levels were significantly increased compared to the control. In the FDF group, all three appetite-regulating hormones showed the highest concentrations in comparison to the other groups.

Conclusion: Sex hormones may affect the appetite-regulation signals and could be a factor contributing to degree of metabolic changes caused by long-term fructose overconsumption.

Consumption of Saturated Fatty Acids-Rich Lard Benefits Recovery of Experimental Arthritis by Activating PPAR-γ

SCOPE

This study investigates the impacts of lard and related fatty acids intake on rheumatoid arthritis (RA) animal models.

METHOD AND RESULTS

Collagen-induced arthritis (CIA) and adjuvant-induced arthritis (AIA) are induced in SD rats and C57 BL/6 mice respectively, which are fed by lard-rich diet (LRD) for 42 days with intake restriction or not. AIA SD rats are treated by representative fatty acids for 30 days. Body weight, arthritis score, and metabolic profile are periodically recorded. Monocyte distribution, cytokine/metabolites levels, gene expression, and tissue damages are investigated by flow cytometry, ELISA, colorimetry, PCR, and histological methods. After being treated by fatty acids in vitro, THP-1 monocytes and the corresponding medium are collected for ELISA, PCR, immunoblotting, and reporter gene assays. Irrespective of intake amounts, LRD decreases inflammatory cytokines and inhibits glycolysis in all rheumatic rodents. Furthermore, it alters monocyte distribution and promotes PPAR-γ expression in AIA mice. Overall evidences show that both saturated (SF) and unsaturated fatty acids (USF) from lard can attenuate inflammation by activating PPAR-γ. Silencing PPAR-γ abrogates their anti-inflammatory effects in vitro. Besides, SF can stimulate TLR4/NF-κB pathway.

CONCLUSION

Lard consumption is beneficial for active inflammatory arthritis recovery. Even SF can activate PPAR-γ and consequently attenuate inflammation.

Correlation of Metabolic Syndrome with Redox Homeostasis Biomarkers: Evidence from High-Fat Diet Model in Wistar Rats

Metabolic Syndrome (MetS) is an extremely complex disease. A non-balanced diet such as high-fat diet (HFD) induces metabolic dysfunction that could modify redox homeostasis. We here aimed at exploring redox homeostasis in male Wistar rats, following 8 weeks of HFD, correlating the eventual modification of selected biomarkers that could be associated with the clinical manifestations of MetS. Therefore, we selected parameters relative to both the glucose tolerance and lipid altered metabolism, but also oxidative pattern. We assessed some biomarkers of oxidative stress i.e., thiols balance, lipid peroxidation and antioxidant barriers, via the use of specific biochemical assays, individuating eventual cross correlation with parameters relative to MetS through a Principal Component Analysis (PCA). The present study shows that 8 weeks of HFD induce MetS in rats, altering glucose and lipid homeostasis and increasing visceral adipose tissue, but also impairing the physiological antioxidant responses that could not counteract the oxidative stress condition. Crucially, cross-correlation analysis suggested that the assessment of specific oxidative stress parameters reported here can provide information comparable to the more widely acquired biomarkers of Mets such as glucose tolerance. Lastly, hepatic steatosis in association with the oxidative stress condition was also highlighted by histological analysis. This research will elucidate the fundamental impact of these oxidative stress parameters on MetS induced in the HFD rat model, tracing paths for developing prevention approaches.

Dietary iron overload enhances Western diet induced hepatic inflammation and alters lipid metabolism in rats sharing similarity with human DIOS

Hepatic iron overload is often concurrent with nonalcoholic fatty liver disease (NAFLD). Dysmetabolic iron overload syndrome (DIOS) is characterized by an increase in the liver and body iron stores and metabolic syndrome components. Increasing evidences suggest an overlap between NAFLD with iron overload and DIOS; however, the mechanism how iron is involved in their pathogenesis remains unclear. Here we investigated the role of iron in the pathology of a rat model of NAFLD with iron overload. Rats fed a Western (high-fat and high-fructose) diet for 26 weeks represented hepatic steatosis with an increased body weight and dyslipidemia. Addition of dietary iron overload to the Western diet feeding further increased serum triglyceride and cholesterol, and enhanced hepatic inflammation; the affected liver had intense iron deposition in the sinusoidal macrophages/Kupffer cells, associated with nuclear translocation of NFκB and upregulation of Th1/M1-related cytokines. The present model would be useful to investigate the mechanism underlying the development and progression of NAFLD as well as DIOS, and to elucidate an important role of iron as one of the "multiple hits" factors.

Obese outbred mice only partially benefit from diet normalization or calorie restriction as preconception care interventions to improve metabolic health and oocyte quality

STUDY QUESTION

Can diet normalization or a calorie-restricted diet for 2 or 4 weeks be used as a preconception care intervention (PCCI) in Western-type diet-induced obese Swiss mice to restore metabolic health and oocyte quality?

SUMMARY ANSWER

Metabolic health and oocyte developmental competence was already significantly improved in the calorie-restricted group after 2 weeks, while obese mice that underwent diet normalization showed improved metabolic health after 2 weeks and improved oocyte quality after 4 weeks.

WHAT IS KNOWN ALREADY

Maternal obesity is linked with reduced metabolic health and oocyte quality; therefore, infertile obese women are advised to lose weight before conception to increase pregnancy chances. However, as there are no univocal guidelines and the specific impact on oocyte quality is not known, strategically designed studies are needed to provide fundamental insights in the importance of the type and duration of the dietary weight loss strategy for preconception metabolic health and oocyte quality.

STUDY DESIGN, SIZE, DURATION

Outbred female Swiss mice were fed a control (CTRL) or high-fat/high-sugar (HF/HS) diet. After 7 weeks, some of the HF mice were put on two different PCCIs, resulting in four treatment groups: (i) only control diet for up to 11 weeks (CTRL_CTRL), (ii) only HF diet for up to 11 weeks (HF_HF), (iii) switch at 7 weeks from an HF to an ad libitum control diet (HF_CTRL) and (iv) switch at 7 weeks from an HF to a 30% calorie-restricted control diet (HF_CR) for 2 or 4 weeks. Metabolic health and oocyte quality were assessed at 2 and 4 weeks after the start of the intervention (n = 8 mice/treatment/time point).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Changes in body weight were recorded. To study the impact on metabolic health, serum insulin, glucose, triglycerides, total cholesterol and alanine aminotransferase concentrations were measured, and glucose tolerance and insulin sensitivity were analyzed at PCCI Weeks 2 and 4. The quality of in vivo matured oocytes was evaluated by assessing intracellular lipid droplet content, mitochondrial activity and localization of active mitochondria, mitochondrial ultrastructure, cumulus cell targeted gene expression and oocyte in vitro developmental competence.

MAIN RESULTS AND THE ROLE OF CHANCE

Significant negative effects of an HF/HS diet on metabolic health and oocyte quality were confirmed (P < 0.05). HF_CTRL mice already showed restored body weight, serum lipid profile and glucose tolerance, similar to the CTRL_CTRL group after only 2 weeks of PCCI (P < 0.05 compared with HF_HF) while insulin sensitivity was not improved. Oocyte lipid droplet volume was reduced at PCCI Week 2 (P < 0.05 compared with HF_HF), while mitochondrial localization and activity were still aberrant. At PCCI Week 4, oocytes from HF_CTRL mice displayed significantly fewer mitochondrial ultrastructural abnormalities and improved mitochondrial activity (P < 0.05), while lipid content was again elevated. The in vitro developmental capacity of the oocytes was improved but did not reach the levels of the CTRL_CTRL mice. HF_CR mice completely restored cholesterol concentrations and insulin sensitivity already after 2 weeks. Other metabolic health parameters were only restored after 4 weeks of intervention with clear signs of fasting hypoglycemia. Although all mitochondrial parameters in HF_CR oocytes stayed aberrant, oocyte developmental competence in vitro was completely restored already after 2 weeks of intervention.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

In this study, we applied a relevant HF/HS Western-type diet to induce obesity in an outbred mouse model. Nevertheless, physiological differences should be considered when translating these results to the human setting. However, the in-depth study and follow-up of the metabolic health changes together with the strategic implementation of specific PCCI intervals (2 and 4 weeks) related to the duration of the mouse folliculogenesis (3 weeks), should aid in the extrapolation of our findings to the human setting.

WIDER IMPLICATIONS OF THE FINDINGS

Our study results with a specific focus on oocyte quality provide important fundamental insights to be considered when developing preconception care guidelines for obese metabolically compromised women wishing to become pregnant.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the Flemish Research Fund (FWO-SB grant 1S25020N and FWO project G038619N). The authors declare there are no conflicts of interest.

Loquat (Eriobotrya japonica (Thunb) Lindl.): Evaluation of nutritional value, polyphenol composition, antidiabetic effect, and toxicity of leaf aqueous extract

ETHNOPHARMACOLOGICAL RELEVANCE

Loquat (Eriobotrya japonica (Thunb.) Lindl.) is an evergreen tree native to China, which is introduced in many Mediterranean countries. As in many ancient medical systems, loquat leaves have been used in Moroccan traditional medicine to treat diabetes and its complications.

AIM OF THE STUDY

This study aims to determine the nutritional and polyphenol composition and to evaluate the in vivo antidiabetic, and antihyperlipidemic properties and oral toxicity of a leaf aqueous extract (LLE) derived from loquat grown in Morocco.

MATERIALS AND METHODS

Energy value and fiber, fatty acids, minerals, vitamins, total carbohydrate, sugar, lipid, and protein contents were determined according to international methods committee guidelines. Polyphenol profiling was carried out using the HPLC-DAD method. Mice fed a high-fat and high-glucose (HFG) diet for 10 weeks were used as a model to assess the antidiabetic and antihyperlipidemic effects of a daily administration of LLE at three different doses (150, 200, 250 mg/kg body weight (BW)/day), in comparison with metformin (50 mg/kg BW/day) and pravastatin (20 mg/kg BW/day). The oral toxicity was determined following OECD 425 Guideline.

RESULTS

Loquat leaves were found to be rich in fiber, minerals (potassium, calcium, magnesium, iron, and sodium), and vitamins (B2, B6, and B12) and lower in energy, sugar, and fat. Ten different phenolic compounds were characterized. Naringenin, procyanidin C1, epicatechin, and rutin were the more abundant compounds in LLE. The administration of the LLE dose-dependently ameliorated hyperglycemia, insulin resistance, oxidative stress, and hyperlipidemia in HFG diet-fed mice. The median lethal dose of LLE was higher than 5000 mg/kg BW.

CONCLUSIONS

Loquat leaves are a potential source of micronutrients and polyphenols with beneficial effects on diabetes and its complications.

Construction of the experimental rat model of gestational diabetes

Objective

Numerous methods for modeling gestational diabetes mellitus (GDM) in rats exist. However, their repeatability and stability are unclear. This study aimed to compare the effects of high-fat and high-sugar (HFHS) diet, HFHS diet combined with streptozotocin (STZ) administration, and HFHS diet combined with movement restriction (MR) modeling methods on rat models to confirm the best method for constructing a rat model of GDM.

Method

Forty female Sprague-Dawley rats were randomly divided into four groups (n = 10): the normal control (NC), HFHS, HFHS+STZ, and HFHS+MR groups. The rats in the NC group were fed with a standard diet, and those in the remaining groups were fed with a HFHS diet. The rats in the HFHS+STZ group received 25 mg/kg STZ on their first day of pregnancy, and those in the HFHS+MR group were subjected to MR during pregnancy. Bodyweight, food intake, water intake, fasting blood glucose (FBG), fasting insulin (FINS), homeostasis model assessment of insulin resistance (HOMA-IR), homeostasis model assessment of insulin sensitivity (HOMA-IS), homeostasis model assessment of β-cell function, pancreatic and placental morphology, and the expression levels of glucose transporter 1 (GLUT1) and glucose transporter 3 (GLUT3) in placentas were then quantified. Moreover, iTRAQ was used to identify placental proteomics.

Results

During pregnancy, the rats in the HFHS+STZ group showed FBG levels that were kept stable in a state of moderate hyperglycemia; the typical GDM symptoms of polydipsia, polyphagia, polyuria, and increased body weight; and the modeling rate of 87.5%. On the first and 19th days of pregnancy, the rats in the HFHS group showed higher FBG than that of the NC group, increasing body weight and food intake and the modeling rate of 50%. On the 19th day of pregnancy, the FBG of the rats in the HFHS+MR group was higher than that of the rats in the NC group, and the modeling rate of 42.9%. Comparison with the NC group revealed that the three modeling groups exhibited increased FINS and HOMA-IR, decreased HOMA-IS, and different degrees of pathological changes in pancreases and placentas. Among the groups, the HFHS+STZ group displayed the greatest changes with significant reductions in the numbers of pancreatic and placental cells and appeared cavitation. The expression levels of GLUT1 and GLUT3 in the placentas of the HFHS+STZ and HFHS+MR groups were higher than those in the placentas of the NC and HFHS groups. The above results indicated that the rats in the HFHS+STZ group showed the best performance in terms of modeling indicators. After the changes in placental proteomics in the HFHS+STZ group were compared with those in the NC group, we found that in the HFHS+STZ group, five proteins were up-regulated and 18 were down-regulated; these proteins were enriched in estrogen signaling pathways.

Conclusion

HFHS combined with the intraperitoneal injection of 25 mg/kg STZ was the best modeling method for the nonspontaneous model of experimentally induced GDM, and its modeling rate was high. The pathological characteristics of the constructed GDM rat model were similar to those of human patients with GDM. Moreover, the model was stable and reliable. The modeling method can provide a basis for constructing a GDM rat model for subsequent research on the prevention and treatment of GDM.

Sargassum fusiforme fucoidan ameliorates diet-induced obesity through enhancing thermogenesis of adipose tissues and modulating gut microbiota

Obesity has become a global epidemic. Sargassum fusiforme fucoidan (Fuc) is a group of water-soluble heteropolysaccharides that exhibits a wide range of medicinal functions. It consists of l-fucose and sulfate groups, with l-fucose as the main monosaccharide. This study investigated the therapeutic effects of Fuc on diet-induced obesity (DIO) in C57BL/6J female mice. Fuc significantly alleviated obesity in mice induced by high-fat high-fructose (HFHF) feeding, inhibiting body weight gain, reducing fat accumulation, and improving hepatic steatosis. In addition, Fuc significantly improved glucose tolerance and insulin sensitivity by enhancing the phosphorylation level of AKT (at Ser473) in the adipose tissues. Mechanistically, although Fuc did not decrease the energy intake in DIO mice, it significantly increased the energy expenditure by up-regulating the expression of uncoupling protein 1 (UCP1) in the adipose tissues. Notably, Fuc also improved the obesity-driven dysbiosis of gut microbiota and decreased the relative abundance of the obesity-related intestinal bacteria. However, Fuc was unable to alleviate DIO-induced metabolic disorders in pseudo-sterile mice. Our findings suggested that Fuc might remodel gut microbiota and exert its weight loss and hypolipidemic effects by increasing the energy expenditure, thus providing a novel perspective for treating obesity and related complications.

Lipomodulatory and anti-oxidative stress effects of a polyherbal formulation based on garlic and avocado seed extracts on high fat high sucrose diet fed rats

Objective

To determine antioxidant potentials of Allium sativum and Persea americana seeds extracts and three formulation-based extracts in vitro, and to evaluate the effects of the best formulation on oxidative stress and dyslipidemia on rats fed with high fat and high sucrose diet (HFHSD).

Methods

Aqueous extracts of Allium sativum, Persia. americana and three formulations were mixed at various portions (A. s/P. a; w/w): F (1:1), F (3: 1), and F(1:3). They were then tested for their antioxidant potentials in vitro using FRAP, DPPH and NO radicals to identify the best formulation. Four hundred (400) mg/kg b.w. of formulation F(1:1) were administered once daily for 21 days to rats previously fed with HFHSD for 8 weeks. Standard diet, vitamin E, and Atorvastatin were used as controls. After 21 days, body weight, blood glucose, lipid markers, activities of transaminases and markers of the antioxidant systems were assessed.

Results

The Formulation F(1:1) showed the best in vitro activity with IC₅₀ values of 6.5 and 2.23 mg/mL respectively for FRAP and DPPH- radical scavenging capacity. HFHSD caused a depletion of antioxidants associated with an increase of pro-oxidants and all the lipid markers except HDL-c Treatment with F(1:1) significantly increased TAC, SOD, and catalase activities, while MDA, protein carbonyls, and NO levels decreased (p < 0.05). Formulation F(1:1) decreased triglycerides (119.88 ± 4.25 mg/dL) and LDL-c (3.78 ± 0.66 mg/dL) levels and significantly increased the HDL-c level: (108.07 ± 6.29 mg/mL). Furthermore, Formulation F(1:1) significantly caused weight loss (2.31%), reduced blood glucose levels (27.38%) and ALT activity.

Conclusion

The formulation F(1:1) could be a good candidate for the prevention and treatment of oxidative stress, dyslipidemia and features of metabolic syndrome.

The Anti-Obesity Effect of Porous Silica Is Dependent on Pore Nanostructure, Particle Size, and Surface Chemistry in an In Vitro Digestion Model

The potential for porous silica to serve as an effective anti-obesity agent has received growing attention in recent years. However, neither the exact pharmacological mechanism nor the fundamental physicochemical properties of porous silica that drive its weight-lowering effect are well understood. Subsequently, in this study, an advanced in vitro digestion model capable of monitoring lipid and carbohydrate digestion was employed to elucidate the effect of porous silica supplementation on digestive enzyme activities. A suite of porous silica samples with contrasting physicochemical properties was investigated, where it was established that the inhibitory action of porous silica on digestive enzyme functionality was strongly dependent on porous nanostructure, particle size and morphology, and surface chemistry. Insights derived from this study validate the capacity of porous silica to impede the digestive processes mediated by pancreatic lipase and α-amylase within the gastrointestinal tract, while the subtle interplay between porous nanostructure and enzyme inhibition indicates that the anti-obesity effect can be optimized through strategic particle design.

Hongqu Rice Wines Ameliorate High-Fat/High-Fructose Diet-Induced Metabolic Syndrome in Rats

AIM

This study evaluated the possible protective impact of different vintages of Hongqu rice wines on metabolic syndrome (MetS) in rats induced by high-fat/high-fructose diet (HFFD).

METHODS

Rats were randomly divided into six groups and treated with (a) basal diet (13.9 kJ/g); (b) HFFD (20.0% w/w lard and 18.0% fructose, 18.9 kJ/g) and (c-f) HFFD with 3-, 5-, 8- and 15-year-aged Hongqu rice wines (9.96 ml/kg body weight), respectively, at an oral route for 20 weeks.

RESULTS

Hongqu rice wines could alleviate HFFD-induced augment of body weight gain and fat accumulation, and the release of pro-inflammatory cytokines. Glycolipid metabolic abnormalities caused by HFFD were ameliorated after Hongqu rice wines consumption by lowering levels of fasting insulin, GSP, HOMA-IR, AUC of OGTT and ITT, and lipid deposition (reduced contents of TG, TC, FFA and LDL-C, and elevated HDL-C level) in the serum and liver, probably via regulating expressions of genes involving in IRS1/PI3K/AKT pathway, LDL-C uptake, fatty acid β-oxidation, and lipolysis, export and synthesis of TG. In addition, concentrations of MDA and blood pressure markers (ANG-II and ET-1) declined, and activities of antioxidant enzymes (SOD and CAT) were improved in conditions of Hongqu rice wines compared to those in the HFFD group. Eight-year-aged Hongqu rice wine produced a more effective effect on alleviating HFFD-caused MetS among different vintages of Hongqu rice wines.

CONCLUSION

To sum up, Hongqu rice wines exhibited ameliorative effects on HFFD-induced MetS in rats based on antiobesity, antihyperlipidemic, antihyperglycemic, antioxidant, anti-inflammatory and potential antihypertensive properties.

The Role of Vitamin E in Thermal Burn Injuries, Infection, and Sepsis: A Review

Thermal burn injuries are still a serious public health concern in the United States, due to the initial insult and resulting comorbidities. Burned patients are increasingly susceptible to colonization by endogenous and exogenous microorganisms after having lost skin, which acts as the primary protective barrier to environmental contaminants. Furthermore, the onset of additional pathophysiologies, specifically sepsis, becomes more likely in burned patients compared to other injuries. Despite improvements in the early care of burn patients, infections, and sepsis, these pathophysiologies remain major causes of morbidity and mortality and warrant further investigation of potential therapies. Vitamin E may be one such therapy. We aimed to identify publications of studies that evaluated the effectiveness of vitamin E as it pertains to thermal burn injuries, infection, and sepsis. Several investigations ranging from in vitro bench work to clinical studies have examined the impact on, or influence of, vitamin E in vitro, in vivo, and in the clinical setting. To the benefit of subjects it has been shown that enteral or parenteral vitamin E supplementation can prevent, mitigate, and even reverse the effects of thermal burn injuries, infection, and sepsis. Therefore, a large-scale prospective observational study to assess the potential benefits of vitamin E supplementation in patients is warranted and could result in clinical care practice paradigm changes.

Microbial and Transcriptomic Profiling Reveals Diet-Related Alterations of Metabolism in Metabolic Disordered Mice

Metabolic disorders are the prelude of metabolic diseases, which are mainly due to the high-energy intake and genetic contribution. High-fat diet (HFD) or high-sucrose diet is widely used for inducing metabolic disorders characterized by increased body weight, insulin resistance, hepatic steatosis, and alteration of gut microbiome. However, the triangle relationship among diets, gut microbiome, and host metabolism is poorly understood. In our study, we investigated the dynamic changes in gut microbiota, and host metabolism in mice that were fed with either chow diet, HFD, or chow diet with 30% sucrose in drinking water (HSD) for continued 12 weeks. The gut microbiota was analyzed with 16S rDNA sequencing on feces. Hepatic gene expression profile was tested with transcriptomics analysis on liver tissue. The host metabolism was evaluated by measuring body weight, insulin sensitivity, serum lipids, and expression of proteins involved in lipid metabolism of liver. The results showed that HFD feeding affected body weight, insulin resistance, and hepatic steatosis more significantly than HSD feeding. 16S rRNA gene sequencing showed that HFD rapidly and steadily suppressed species richness, altered microbiota structure and function, and increased the abundance of bacteria responsible for fatty acid metabolism and inflammatory signaling. In contrast, HSD had minor impact on the overall bacteria structure or function but activated microbial bile acid biosynthesis. Fecal microbiota transplantation suggested that some metabolic changes induced by HFD or HSD feeding were transferrable, especially in the weight of white adipose tissue and hepatic triglyceride level that were consistent with the phenotypes in donor mice. Moreover, transcriptomic results showed that HFD feeding significantly inhibited fatty acid degradation and increase inflammation, while HSD increased hepatic de novo lipogenesis and inhibited primary bile acid synthesis alternative pathway. In general, our study revealed the dynamic and diversified impacts of HFD and HSD on gut microbiota and host metabolism.

Characterization and Comparison of the Divergent Metabolic Consequences of High-Sugar and High-Fat Diets in Male Wistar Rats

Diet-induced obesity (DIO) in laboratory rodents can serve as a model with which to study the pathophysiology of obesity, but obesogenic diets (high-sugar and/or high-fat) are often poorly characterised and simplistically aimed at inducing metabolic derangements for the purpose of testing the therapeutic capacity of natural products and other bioactive compounds. Consequently, our understanding of the divergent metabolic responses to different obesogenic diet formulations is limited. The aim of the present study was to characterise and compare differences in the metabolic responses induced by low-fat, medium-fat/high-sugar and high-fat diets in rats through multivariate statistical modelling. Young male Wistar rats were randomly assigned to CON (laboratory chow, low-fat), OB1 (high-sugar, medium-fat) or OB2 (high-fat) dietary groups (n = 24 each) for 17 weeks, after which metabolic responses were characterised. Projection-based multivariate analyses (principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA)) were used to explore the associations between measures of body composition and metabolism. Furthermore, we conducted a systematic literature survey to examine reporting trends in rat dietary intervention studies, and to determine how the metabolic responses observed in the present study compared to other recently published studies. The OB1 and OB2 dietary regimens resulted in distinct metabolic profiles, with OB1 characterised by perturbations in insulin homeostasis and adipose tissue secretory function, while OB2 was characterised by altered lipid and liver metabolism. This work therefore confirms, by means of direct comparison, that differences in dietary composition have a profound impact on metabolic and pathophysiological outcomes in rodent models of DIO. However, through our literature survey we demonstrate that dietary composition is not reported in the majority of rat dietary intervention studies, suggesting that the impact of dietary composition is often not considered during study design or data interpretation. This hampers the usefulness of such studies to provide enhanced mechanistic insights into DIO, and also limits the translatability of such studies within the context of human obesity.

Recent advances in lean NAFLD

As the predominant type of chronic liver disease, the growing prevalence of nonalcoholic fatty liver disease (NAFLD) has become a concern worldwide. Although obesity plays the most pivotal role in NAFLD, approximately 10-20% of individuals with NAFLD who are not overweight or obese (BMI < 25 kg/m2, or BMI < 23 kg/m2 in Asians) have "lean NAFLD." Lean individuals with NAFLD have a lower prevalence of diabetes, hypertension, hypertriglyceridemia, central obesity, and metabolic syndrome than nonlean individuals with NAFLD, but higher fibrosis scores and rates of cardiovascular morbidity and all-cause mortality in advanced stages. The pathophysiological mechanisms of lean NAFLD remain poorly understood. Studies have shown that lean NAFLD is more correlated with factors such as environmental, genetic susceptibility, and epigenetic regulation. This review will examine the way in which the research progress and characteristic of lean NAFLD, and explore the function of epigenetic modification to provide the basis for the clinical treatment and diagnosis of lean NAFLD.

Neurovascular Dysfunction in Diverse Communities With Health Disparities-Contributions to Dementia and Alzheimer's Disease

Alzheimer's disease and related dementias (ADRD) are an expanding worldwide crisis. In the absence of scientific breakthroughs, the global prevalence of ADRD will continue to increase as more people are living longer. Racial or ethnic minority groups have an increased risk and incidence of ADRD and have often been neglected by the scientific research community. There is mounting evidence that vascular insults in the brain can initiate a series of biological events leading to neurodegeneration, cognitive impairment, and ADRD. We are a group of researchers interested in developing and expanding ADRD research, with an emphasis on vascular contributions to dementia, to serve our local diverse community. Toward this goal, the primary objective of this review was to investigate and better understand health disparities in Alabama and the contributions of the social determinants of health to those disparities, particularly in the context of vascular dysfunction in ADRD. Here, we explain the neurovascular dysfunction associated with Alzheimer's disease (AD) as well as the intrinsic and extrinsic risk factors contributing to dysfunction of the neurovascular unit (NVU). Next, we ascertain ethnoregional health disparities of individuals living in Alabama, as well as relevant vascular risk factors linked to AD. We also discuss current pharmaceutical and non-pharmaceutical treatment options for neurovascular dysfunction, mild cognitive impairment (MCI) and AD, including relevant studies and ongoing clinical trials. Overall, individuals in Alabama are adversely affected by social and structural determinants of health leading to health disparities, driven by rurality, ethnic minority status, and lower socioeconomic status (SES). In general, these communities have limited access to healthcare and healthy food and other amenities resulting in decreased opportunities for early diagnosis of and pharmaceutical treatments for ADRD. Although this review is focused on the current state of health disparities of ADRD patients in Alabama, future studies must include diversity of race, ethnicity, and region to best be able to treat all individuals affected by ADRD.

Metabolic Syndrome: Lessons from Rodent and Drosophila Models

Overweight and obesity are health conditions tightly related to a number of metabolic complications collectively called “metabolic syndrome” (MetS). Clinical diagnosis of MetS includes the presence of the increased waist circumference or so-called abdominal obesity, reduced high density lipoprotein level, elevated blood pressure, and increased blood glucose and triacylglyceride levels. Different approaches, including diet-induced and genetically induced animal models, have been developed to study MetS pathogenesis and underlying mechanisms. Studies of metabolic disturbances in the fruit fly Drosophila and mammalian models along with humans have demonstrated that fruit flies and small mammalian models like rats and mice have many similarities with humans in basic metabolic functions and share many molecular mechanisms which regulate these metabolic processes. In this paper, we describe diet-induced, chemically and genetically induced animal models of the MetS. The advantages and limitations of rodent and Drosophila models of MetS and obesity are also analyzed.