Prevention Of Insulin Resistance Research Articles

Pharmacological effect of Hibiscus sabdariffa linn to prevent insulin resistance: a review

To date, no effective treatment has been found to improve the quality of life and condition of patients with diabetes mellitus. Currently, people are interested in using herbal medicines to treat diabetes mellitus or control hyperglycemia. Hibiscus sabdariffa Linn (roselle) calyx extract has been widely documented in various literatures for the treatment of several diseases, including diabetes mellitus. Roselle has many phytoconstituents, but roselle pharmacological mechanism of action and its active substances that are associated with insulin resistance prevention are still little known. This review identified the phytochemical constituent and potential effect of roselle extract to prevent insulin resistance through analysis of a network pharmacology approach and subsequent experimental research. The mechanism of action of roselle has not been explained in detail, though hypoxia inducible factor-1 pathway might be involved due to its anthocyanin content. Therefore, upcoming research needs to be carried out to answer the questions.

Association of serum total IgE and allergen-specific IgE with insulin resistance in adolescents: an analysis of the NHANES database

BackgroundRecent studies have found that total immunoglobulin E (IgE) and allergen-specific IgE were associated with some metabolic diseases. However, the role of IgE in metabolism among adolescents is still unclear. Herein, this study aims to investigate the associations of serum total IgE and allergen-specific IgE with insulin resistance (IR) in adolescents, in order to provide some reference for the prevention and treatment of metabolic diseases in a young age.MethodsData of 870 adolescents were extracted from the National Health and Nutrition Examination Survey (NHANES) database in 2005–2006 in this cross-sectional study. Weighted univariate and multivariate logistic regression analyses were utilized to screen covariates and explore the relationships of serum total IgE and allergen-specific IgE with IR. The evaluation indexes were odds ratios (ORs) and 95% confidence intervals (CIs). In addition, these relationships were also assessed in subgroups of allergy history, asthma history, and number of allergens.ResultsAmong eligible adolescents, 168 had IR. No significant association between serum total IgE level and IR was found. However, adolescents with higher level of allergen-specific IgE to rye grass [OR = 0.47, 95%CI: (0.25–0.91)], white oak [OR = 0.57, 95%CI: (0.37–0.88)], or peanut [OR = 0.38, 95%CI: (0.15–0.97)] seemed to have lower odds of IR, whereas those had higher level of shrimp-specific IgE [OR = 2.65, 95%CI: (1.21–5.84)] have increased odds of IR. In addition, these associations between allergen-specific IgE and IR were also discovered in adolescents who had allergy history or asthma history, or had different numbers of allergens.ConclusionPaying attention to different allergens in adolescents may be important in the early identification of IR among this high-risk population. The study results relatively provided some reference for further exploration on IR prevention.

Metformin Blunts Bed Rest-induced Skeletal Muscle Ceramide Accumulation in Older Adults

Skeletal muscle insulin resistance is an undesirable outcome during periods of physical inactivity in older adults, which can lead to a variety of metabolic diseases. Insulin sensitive tissue (e.g., liver, and skeletal muscle) derived ceramides are well known to promote insulin resistance. Evidence suggests that metformin can regulate tissue ceramide accumulation. Therefore, we hypothesized that metformin treatment during a short-term period of bed rest in male and female older adults would reduce skeletal muscle ceramide accumulation and prevent insulin resistance. Our study design consisted of older adults (66 ± 4.5 y/o placebo, n=10; 71.7 ± 5.1 y/o metformin, n=10) who were subjected to 5 days of bed rest. Participants were randomly assigned to placebo or metformin treatment groups. Drug or placebo treatments started two weeks prior to bed rest and continued throughout the 5 days of bed rest. Prior to and after bed rest, participants underwent a euglycemic-hyperinsulinemic clamp. Muscle biopsies (from the vastus lateralis) were taken prior to and after each clamp both before and after bed rest. We found that insulin-stimulated muscle ceramides were increased after bed rest but were blunted in older adults who took metformin. In addition, muscle insulin resistance correlated with the increase in ceramides. We conclude that metformin was effective to reduce ceramide accumulation in muscle during a period of bed rest in older adults. R21AG064576 awarded to M.J.D. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Metabolic regulator LKB1 controls adipose tissue ILC2 PD-1 expression and mitochondrial homeostasis to prevent insulin resistance

Adipose tissue group 2 innate lymphoid cells (ILC2s) help maintain metabolic homeostasis by sustaining type 2 immunity and promoting adipose beiging. Although impairment of the ILC2 compartment contributes to obesity-associated insulin resistance, the underlying mechanisms have not been elucidated. Here, we found that ILC2s in obese mice and humans exhibited impaired liver kinase B1 (LKB1) activation. Genetic ablation of LKB1 disrupted ILC2 mitochondrial metabolism and suppressed ILC2 responses, resulting in exacerbated insulin resistance. Mechanistically, LKB1 deficiency induced aberrant PD-1 expression through activation of NFAT, which in turn enhanced mitophagy by suppressing Bcl-xL expression. Blockade of PD-1 restored the normal functions of ILC2s and reversed obesity-induced insulin resistance in mice. Collectively, these data present the LKB1-PD-1 axis as a promising therapeutic target for the treatment of metabolic disease.

The tandem of Fibroblast Growth Factor (FGF21) and Adipocyte Fatty Acid Binding Protein (A-FABP) as a physiological macronutrient signal to prevent insulin resistance

The tandem of Fibroblast Growth Factor (FGF21) and Adipocyte Fatty Acid Binding Protein (A-FABP) as a physiological macronutrient signal to prevent insulin resistance

Chickpea proteins are potential sources of bioactive peptides that induce glucose uptake via AMP-activated protein kinase

Food proteins are a critical source of nutraceutical bioactive peptides that promote health and prevent diseases. Legume seed proteins have been extensively studied to produce peptides with diverse biological activities. Several legume protein hydrolysates and bioactive peptides have been identified that inhibit the activity of α-amylase, α-glucosidase, and dipeptidyl peptidase IV for the purpose of preventing diabetes. Herein, we observed that chickpea peptides (CPP), prepared using the enzymatic digestion of chickpea protein, induced glucose uptake in C2C12 myotubes. Further, liquid chromatography-tandem mass spectrometry and 2-deoxyglucose uptake assay were used to identify a bioactive CPP, defined as CPP737, REGDIIAVPTGVVF, a part of the legumin A-like protein. CPP737 induced AMP-activated protein kinase phosphorylation and glucose transporter type 4 membrane translocation, but not protein kinase B in C2C12 myotubes. Thus, chickpea protein is a potential source of bioactive peptides that can prevent insulin resistance and hyperglycemia through glucose uptake in the skeletal muscle.

Influence of nutrition on gestational diabetes in Brazil

Nutritional screening can be preventive or therapeutic, helping to prevent and treat diseases related to eating habits or genetic conditions. In the context of gestational diabetes (DG), dietitian follow-up is essential to prevent insulin resistance from progressing to type 2 diabetes. The article also promotes the importance and risk that accompanies the presence or absence of the appropriate BMI, thus bringing a brief quote from Pedrini, we can assess in a concrete way the risk that accompanies your pregnancy if there is absence of more balanced eating habits. With this, the later development concludes the best approaches that should remain during and after pregnancy, exposing data and new sources so that everyone absorbs what is being exposed in the article. The following bibliographic review aims to discuss the importance of nutritional monitoring during pregnancy, especially in cases of DG. The article's methodology is based on a narrative bibliographic discussion, based on prospecting and selection of articles from 2016 to the present date. The research was carried out in a narrative-descriptive manner, with a qualitative analysis of the proposed theme. The theoretical basis of the work includes several sources, such as the Brazilian Ministry of Health, Mendes (2019), Government of the State of Bahia (2017), Lucena et al. (2021), among others. The promotion described is linked to the importance of nutritional therapy and its necessity during pregnancy for the treatment of gestational diabetes. The text presents two subsections of bibliographic review: one on the action of the nutritionist in prevention and nutritional therapy, and another on the action of the nutritionist in cases of DG in Brazil. The research in question allowed for a contemplation that the main influence of nutrition in the face of gestational diabetes in Brazil says about nutritional therapy as an important tool to prevent the DG from evolving to a diabetes mellitus in the woman during or after pregnancy.

Daily Consumption of Golden Berry (Physalis peruviana) Has Been Shown to Halt the Progression of Insulin Resistance and Obesity in Obese Rats with Metabolic Syndrome.

In a study addressing the high risk of chronic diseases in people with diabetes and obesity linked to metabolic syndrome, the impact of a Golden Berry diet was investigated using a diabetic animal model. Obese rats with diabetic characteristics were fed a diet containing five percent Golden Berry for 16 days. This study focused on various parameters including organ weights, expression of metabolic genes, and urinary biomarkers. Post-Golden Berry intake, there was a notable decrease in the body, liver, pancreas, visceral, and subcutaneous adipose tissue weights in these obese, hyperglycemic rats. In contrast, an increase in brown adipose tissue (BAT) cell mass was observed. This diet also resulted in reduced blood glucose levels and normalized plasma biochemical profiles, including cholesterol, triglycerides, LDL, and HDL levels. Additionally, it modulated specific urinary biomarkers, particularly pipe-colic acid, a primary marker for type 2 diabetes. Bioinformatics analysis linked these dietary effects to improved insulin signaling and adipogenesis. Regular consumption of Golden Berry effectively prevented insulin resistance and obesity in rats, underscoring its significant health benefits and the protective role of an antioxidant-rich diet against metabolic syndrome. These findings offer promising insights for future therapeutic strategies to manage and prevent obesity and related chronic diseases.

Hydroalcoholic extract from Sechium edule (Jacq.) S.w. root reverses oleic acid-induced steatosis and insulin resistance in vitro

Steatosis is characterized by fat accumulation and insulin resistance (IR) in hepatocytes, which triggers a pro-oxidant, pro-inflammatory environment that may eventually lead to cirrhosis or liver carcinoma. This work was aimed to assess the effect of Sechium edule root hydroalcoholic extract (rSe-HA) (rich in cinnamic and coumaric acid, among other phenolic compounds) on triglyceride esterification, lipid degradation, AMPK expression, and the phosphorylation of insulin receptor in a Ser312 residue, as well as on the redox status, malondialdehyde (MDA) production, and the production of proinflammatory cytokines in an in vitro model of steatosis induced by oleic acid, to help develop a phytomedicine that could reverse this pathology. rSe-HA reduced triglyceride levels in hepatocyte lysates, increased lipolysis by activating AMPK at Thr172, and improved the redox status, as evidenced by the concentration of glycerol and formazan, respectively. It also prevented insulin resistance (IR), as measured by glucose consumption and the phosphorylation of the insulin receptor at Ser312. It also prevented TNFα and IL6 production and decreased the levels of MDA and nitric oxide (ON). Our results indicate that rSe-HA reversed steatosis and controlled the proinflammatory and prooxidant environment in oleic acid-induced dysfunctional HepG2 hepatocytes, supporting its potential use to control this disorder.

The polysaccharides from the fruits of Lycium barbarum ameliorate high-fat and high-fructose diet-induced cognitive impairment via regulating blood glucose and mediating gut microbiota

High-fat and high-fructose diet (HFFD) consumption can induce cognitive dysfunction and gut microbiota disorder. In the present study, the effects of the polysaccharides from the fruits of Lycium barbarum L. (LBPs) on HFFD-induced cognitive deficits and gut microbiota dysbiosis were investigated. The results showed that intervention of LBPs (200 mg/kg/day) for 14 weeks could significantly prevent learning and memory deficits in HFFD-fed mice, evidenced by a reduction of latency and increment of crossing parameters of platform quadrant in Morris water maze test. Moreover, oral administration of LBPs enhanced the expression of postsynaptic density protein 95 and brain-derived neurotrophic factor and reduced the activation of glial cells in hippocampus. Besides, LBPs treatment enriched the relative abundances of Allobaculum and Lactococcus and reduced the relative abundance of Proteobacteria in gut bacterial community of HFFD-fed mice, accompanied by increased levels of short-chain fatty acids (SCFAs) as well as expression of associated G protein-coupled receptors. Furthermore, LBPs intervention prevented insulin resistance, obesity and colonic inflammation. Finally, a significant correlation was observed among neuroinflammation associated parameters, gut microbiota and SCFAs through Pearson correlation analysis. Collectively, these findings suggested that the regulation of gut microbiota might be the potential mechanism of LBPs on preventing cognitive dysfunction induced by HFFD.

In silico determination of fenthion, permethrin, and carbaryl as FFAR2 inhibitors: Type 2 diabetes mellitus pathomechanism study

Background: In the last few decades, many studies have shown that pesticides have a close relationship with increasing blood glucose levels and the incidence of diabetes. Some examples of pesticides include fenthion, permethrin, and carbaryl. Recently, free fatty acid receptor 2 (FFAR2) was identified as having a critical function in preventing insulin resistance. Activation of FFAR2 will reduce fat accumulation and induce glucagon-like peptide 1 (GLP-1) secretion, which plays an important role in regulating type 2 diabetes mellitus (T2DM) prevention.Objective: This study aims to determine a comparison of the binding ability between fenthion, permethrin, and carbaryl to FFAR2 protein for predicting the mechanism of pesticide toxicity to T2DM through an in silico study.Methods: This is an exploratory bioinformatic study. The protein structure was FFAR2 receptor (UniProt: O15552), while the ligand was fenthion (PubChem CID: 3346), permethrin (PubChem CID: 40326), and carbaryl (PubChem CID: 6129). This molecular docking was conducted in October 2022 using Asus X202XE with Intel® Core™ i3-3217U CPU equipped with BIOVIA Discovery Studio, AutoDockTools, and AutoDock Vina. Results: The binding affinity values generated after docking between fenthion, permethrin, and carbaryl with FFAR2 indicate that the binding affinity comparison is permethrin < carbaryl < fenthion. This explains that permethrin could form a stronger bond with FFAR2 protein than other pesticides. However, the visualisation results of the form of bond interactions show that permethrin does not bind to the active site of FFAR2, so it could not be called an inhibitor. This is different from fenthion and carbaryl, which could bind to several amino acid residues on the active site of FFAR2 and have the potential to become inhibitors.Conclusion: Carbaryl is a pesticide with the strongest FFAR2 inhibitor. Carbaryl could cause type 2 DM through its inhibitory pathway to FFAR2.

INFLUENCE OF A POOR LIFESTYLE ON THE DEVELOPMENT OF CYSTS IN WOMEN

Poor lifestyle choices, such as frequently consuming fatty fast food, consuming sugary beverages, living a sedentary lifestyle, and not getting enough exercise, may hasten the ovarian hyperthecosis progression. A recurrent hormonal disorder that affects women of reproductive age (15-30) known as polycystic ovarian disease (PCOD), where the ovaries contain an abundance of tiny cysts. It might interfere with their menstrual cycles and complicate attempts to conceive. PCOD is a serious health issue since those who have it have a higher risk factors include endometrial hyperplasia, endometrial cancer, obesity, cardiovascular disease, diabetes mellitus, obstructive sleep apnea, depression, and nonalcoholic fatty liver disease. Endometrial cancer may be brought on by aberrant, unopposed endogenous estrogenic stimulation brought on by feminizing ovarian tumors and polycystic ovarian syndrome. Patients with polycystic ovarian disease support the finding that endometrial carcinoma with a concurrent endogenous estrogenic stimulation has a better prognosis (P0.01) than endometrial carcinoma alone. A mature follicle, which is also a cystic structure, develops throughout a typical menstrual cycle with ovulation. The symptoms and potential problems of PCOD appear to be well managed by lifestyle changes. Depending on the condition, medication or lifestyle adjustments may be necessary. Getting regular exercise, losing weight, and increasing your daily activity can all help treat or perhaps prevent insulin resistance and lower testosterone levels. Synthetic medications can be used to treat PCOD. This paper contains the correlation between the poor life style and the occurrence of PCOD in women and its cure

Compound Molecules of Network Pharmacology-Based of Tamarillo (Cyphomandra betacea Cav.) and the Potential as Noodle for Type 2 Diabetes Mellitus Treatment

Consuming noodles excessively is not good for health because it contains high trans fat, which can cause diabetes mellitus (DM) as a disease with a high prevalence, especially type 2 DM, as much as 95% in Indonesia. Tamarillo (Chypomandra betacea Cav.) can potentially reduce blood glucose levels and restore adipokine regulation to prevent insulin resistance in type 2 DM. This study aims to determine the formulation and potential of tamarillo compounds into noodle products named "Chypotes (Chypomandra Antidiabetes) Noodle" as an alternative food for type 2 DM patients. The methods used are noodle formulation, organoleptic test, hedonic test, and network pharmacology. Based on the results of an organoleptic test, Chypotes Noodle has a chewy texture, a distinctive smell, yellow colour, and a slightly sour tasteless taste typical of Tamarillo. Based on the results of the hedonic test, 30 respondents chose the like and very like options in filling out the questionnaire with a percentage of 80-90%. Based on the Network Pharmacology of Tamarillo shows that 150 of the 365 target proteins of Tamarillo are involved in the biological processes and signaling pathways of type 2 diabetes mellitus, with 75 target proteins locking and interacting. Compound Molecules of Tamarillo, such as six bioactive components of the hydroxycinnamic acids group, have activity in type 2 DM and affect the biological processes and signaling pathways of type 2 DM against ADIPOQ, TNF, and INS. Therefore, Tamarillo can potentially be used as an alternative food product in the form of noodles for type 2 DM treatment.

Parabacteroides distasonis ameliorates insulin resistance via activation of intestinal GPR109a

Gut microbiota plays a key role in insulin resistance (IR). Here we perform a case-control study of Chinese adults (ChiCTR2200065715) and identify that Parabacteroides distasonis is inversely correlated with IR. Treatment with P. distasonis improves IR, strengthens intestinal integrity, and reduces systemic inflammation in mice. We further demonstrate that P. distasonis-derived nicotinic acid (NA) is a vital bioactive molecule that fortifies intestinal barrier function via activating intestinal G-protein-coupled receptor 109a (GPR109a), leading to ameliorating IR. We also conduct a bioactive dietary fiber screening to induce P. distasonis growth. Dendrobium officinale polysaccharide (DOP) shows favorable growth-promoting effects on P. distasonis and protects against IR in mice simultaneously. Finally, the reduced P. distasonis and NA levels were also validated in another human type 2 diabetes mellitus cohort. These findings reveal the unique mechanisms of P. distasonis on IR and provide viable strategies for the treatment and prevention of IR by bioactive dietary fiber.

Integrating serum pharmacochemistry and network pharmacology to reveal the mechanism of chickpea in improving insulin resistance

Although chickpea have great potential in the treatment of obesity and diabetes, the bioactive components and therapeutic targets of chickpea to prevent insulin resistance (IR) are still unclear. The purpose of this study was to investigate the chemical and pharmacological characteristics of chickpea on IR through serum pharmacochemistry and network pharmacology. The results revealed that compared with other polar fractions, the ethyl acetate extract of chickpea (CE) had the definitive performance on enhancing the capacities of glucose consumption and glycogen synthesis. In addition, we analyzed the components of CE in vivo and in vitro based on UPLC-Q-Orbitrap HRMS technology. There were 28 kinds of in vitro chemical components, among which the isoflavones included biochanin A, formononetin, ononin, sissotrin, and astragalin, etc. Concerningly, the chief prototype components of CE absorbed into the blood were biochanin A, formononetin, loliolide, and lenticin, etc. Furthermore, a total of 209 common targets between IR and active components of CE were screened out by network pharmacology, among which the key targets involved PI3K p85, NF-κB p65 and estrogen receptor 1, etc. Specifically, KEGG pathway analysis indicated that PI3K-AKT signaling pathway, HIF-1 signaling pathway, and AGE-RAGE signaling pathway may play critical roles in the IR remission by CE. Finally, the in vitro validation experiments disclosed that CE significantly balanced the oxidative stress state of IR-HepG2 cells and inhibited expressions of inflammatory cytokines. In conclusion, the present study will be an important reference for clarifying the pharmacodynamic substance basis and underlying mechanism of chickpea to alleviate IR.

High-protein diet with excess leucine prevents inactivity-induced insulin resistance in women

Background and aimsMuscle inactivity leads to muscle atrophy and insulin resistance. The branched-chain amino acid (BCAA) leucine interacts with the insulin signaling pathway to modulate glucose metabolism. We have tested the ability of a high-protein BCAA-enriched diet to prevent insulin resistance during long-term bed rest (BR). MethodsStable isotopes were infused to determine glucose and protein kinetics in the postabsorptive state and during a hyperinsulinemic-euglycemic clamp in combination with amino acid infusion (Clamp+AA) before and at the end of 60 days of BR in two groups of healthy, young women receiving eucaloric diets containing 1 g of protein/kg per day (n=8) or 1.45 g of protein/kg per day enriched with 0.15 g/kg per day of BCAAs (leucine/valine/isoleucine=2/1/1) (n=8). Body composition was determined by Dual X-ray Absorptiometry. ResultsBR decreased lean body mass by 7.6±0.3% and 7.2±0.8% in the groups receiving conventional or high protein-BCAA diets, respectively. Fat mass was unchanged in both groups.At the end of BR, percent changes of insulin-mediated glucose uptake significantly (p=0.01) decreased in the conventional diet group from 155±23% to 84±10% while did not change significantly in the high protein-BCAA diet group from 126±20% to 141±27% (BR effect, p=0.32; BR/diet interaction, p=0.01; Repeated Measures ANCOVA). In contrast, there were no BR/diet interactions on proteolysis and protein synthesis Clamp+AA changes in the conventional diet and the high protein-BCAA diet groups. ConclusionA high protein-BCAA enriched diet prevented inactivity-induced insulin resistance in healthy women.

SAT045 Sexually Dimorphic Effects Of CCN5/WISP2 Overexpression On HFD-STZ Induced Diabetes And Glucose Intolerance

Abstract Disclosure: T. Alami: None. M. Zakikhani: None. V. Xega: None. J. Liu: None. Matricellular protein CCN5/WISP2 is a novel target of IGF-1 and WNT signaling within the pancreatic islets (1). Our previous works suggest that CCN5 promotes β-cell proliferation and survival via Akt/PKB and focal adhesion kinase. Last year, we reported sexually dimorphic effects of CCN5 knockout in glucose tolerance and insulin sensitivity in high-fat diet (HFD)-induced obesity, supporting a trophic role of endogenous CCN5 expression on pancreatic islets, albeit mostly in male mice (PSUN136, ENDO 2022). In order to further establish the in vivo effect of CCN5 in a gain-of-function approach, we assessed aP2-CCN5 transgenic mice which overexpress CCN5 in adipose tissues (2). These mice have increased serum level of CCN5, lean body mass and whole-body energy expenditure and hyperplastic adipose and cardiac tissues. Obese aP2-CCN5 mice remained insulin sensitive, glucose tolerant with a reduced insulin level. We first fed wild-type and transgenic mice, both male and female, a 60% HFD (Research Diets, D12492) for two weeks before administering 50 mg/kg streptozotocin (STZ) injections for 5 days, every other day. (i) In male mice, the HFD-STZ induced a steady elevation in glycemia from ∼9 to 25 mM in 7 weeks; CCN5 overexpression slowed down and curtailed the elevation to only 16 mM, and improved glucose tolerance at 48 days, suggesting a partial but significant protection from diabetes. (ii) Using the same dose of STZ, female wild-type mice exhibited only a slight elevation in glycemia from 8 to 12 mM. However, female aP2-CCN5 mice displayed a steady increase in glycemia to 18 mM and significantly impaired glucose tolerance at 16 and 48 days, suggesting rather worsening diabetes due to CCN5. In both male and female mice, there was no obvious difference in insulin sensitivity at 21 days nor in the overall weight loss caused by STZ injections. We are still analyzing the corresponding changes in serum insulin level and β-cell morphometry. Our results further support the notion that increased CCN5 level protects the β-cells, although only in male mice. The female environment, however, would abolish CCN5-induced protection. (1) Chowdhury S, Wang X, Srikant CB, Li Q, Fu M, Gong YJ, Ning G, Liu JL. IGF-I stimulates CCN5/WISP2 gene expression in pancreatic beta-cells, which promotes cell proliferation and survival against streptozotocin. Endocrinology. 2014; 155: 1629-1642. (2) Grunberg JR, Hoffmann JM, Hedjazifar S, Nerstedt A, Jenndahl L, Elvin J, Castellot J, Wei L, Moverare-Skrtic S, Ohlsson C, Holm LM, Backhed F, Syed I, Bosch F, Saghatelian A, Kahn BB, Hammarstedt A, Smith U. Overexpressing the novel autocrine/endocrine adipokine WISP2 induces hyperplasia of the heart, white and brown adipose tissues and prevents insulin resistance. Sci Rep. 2017; 7:43515 Presentation: Saturday, June 17, 2023

Inositol polyphosphate multikinase modulates free fatty acids-induced insulin resistance in primary mouse hepatocytes.

Insulin resistance is a critical mediator of the development of nonalcoholic fatty liver disease (NAFLD). An excess influx of fatty acids to the liver is thought to be a pathogenic cause of insulin resistance and the development of NAFLD. Although elevated levels of free fatty acids (FFA) in plasma contribute to inducing insulin resistance and NAFLD, the molecular mechanism is not completely understood. This study aimed to determine whether inositol polyphosphate multikinase (IPMK), a regulator of insulin signaling, plays any role in FFA-induced insulin resistance in primary hepatocytes. Here, we show that excess FFA decreased IPMK expression, and blockade of IPMK decrease attenuated the FFA-induced suppression of protein kinase B (Akt) phosphorylation in primary mouse hepatocytes (PMH). Moreover, overexpression of IPMK prevented the FFA-induced suppression of Akt phosphorylation by insulin, while knockout of IPMK exacerbated insulin resistance in PMH. In addition, treatment with MG132, a proteasomal inhibitor, inhibits FFA-induced decrease in IPMK expression and Akt phosphorylation in PMH. Furthermore, treatment with the antioxidant N-acetyl cysteine (NAC) significantly attenuated the FFA-induced reduction of IPMK and restored FFA-induced insulin resistance in PMH. In conclusion, our findings suggest that excess FFA reduces IPMK expression and contributes to the FFA-induced decrease in Akt phosphorylation in PMH, leading to insulin resistance. Our study highlights IPMK as a potential therapeutic target for preventing insulin resistance and NAFLD.

An insight into the importance of B vitamins and melatonin in the prevention of diabetes through modulation of the brain energy metabolism- a comprehensive review

Energy metabolism is the biochemical pathway of converting macronutrients (carbohydrates, protein, and fat) to cellular energy for the maintenance of cell homeostasis. The brain is an organ that consumes unproportional energy compared to its size. Glucose (glycogen, in storage form of glucose) is the principal source of brain energy. Impairment in brain energy metabolism results in neuronal loss and subsequent neurodegenerative diseases including AD, PD, amyotrophic lateral sclerosis, Huntington’s disease, etc. However, metabolic disorders such as chronic hyperglycemia, and insulin resistance are also linked with neuronal activity. Dysregulation in neuronal transmission is associated with oxidative stress and brain insulin resistance. Diabetes mellitus jeopardizes brain function through various mechanisms including glucose toxicity, BBB damage, neuroinflammation, and gliosis. B vitamins as antioxidants and neuroprotective agents, can improve brain glucose metabolism. Melatonin is a potent free radical scavenger and it can also modulate cellular cytokine levels and prevent insulin resistance. The neuroprotective and antihyperglycemic effects of melatonin improve the brain's antioxidant defense system, decrease brain NOS activity, and prevent glucose toxicity. Hence this review suggests a therapeutic use of a combination of melatonin and B vitamins to improve brain functioning disrupted by diabetes.

Recent Advances in Nutraceuticals for the Treatment of Sarcopenic Obesity.

Sarcopenic obesity, low muscle mass, and high body fat are growing health concerns in the aging population. This review highlights the need for standardized criteria and explores nutraceuticals as potential therapeutic agents. Sarcopenic obesity is associated with insulin resistance, inflammation, hormonal changes, and reduced physical activity. These factors lead to impaired muscle activity, intramuscular fat accumulation, and reduced protein synthesis, resulting in muscle catabolism and increased fat mass. Myostatin and irisin are myokines that regulate muscle synthesis and energy expenditure, respectively. Nutritional supplementation with vitamin D and calcium is recommended for increasing muscle mass and reducing body fat content. Testosterone therapy decreases fat mass and improves muscle strength. Vitamin K, specifically menaquinone-4 (MK-4), improves mitochondrial function and reduces muscle damage. Irisin is a hormone secreted during exercise that enhances oxidative metabolism, prevents insulin resistance and obesity, and improves bone quality. Low-glycemic-index diets and green cardamom are potential methods for managing sarcopenic obesity. In conclusion, along with exercise and dietary support, nutraceuticals, such as vitamin D, calcium, vitamin K, and natural agonists of irisin or testosterone, can serve as promising future therapeutic alternatives.