Link between Metabolic Syndrome and Insulin Resistance

Effects of a multicomponent intervention on cardiovascular risk factors in overweight children: a randomized clinical trial in light of complex systems

Analyzing the effects of interventions from a theoretical and statistical perspective that allows understanding these dynamic relationships of obesity etiology can be a more efficient and innovative way of understanding the phenomenon's complexity. Thus, we aimed to analyze the pattern of cardiovascular risk factors between-participants, and the effects within-participants of a multidisciplinary intervention on cardiovascular risk factors in overweight children. This is a randomized clinical trial, and 41 participated in this study. A multicomponent intervention (physical activities, nutritional and psychological counseling) was performed for 10 weeks. Anthropometric and hemodynamics measurements, lipid and glucose profile, cardiorespiratory fitness, and left ventricular mass were evaluated. A network analysis was done. Considering patterns in the network at baseline, WC, WHR, BMI, and Fat were the main variables for cardiovascular risks. Group was the most critical variable in the within-participant network. Participating in a multicomponent intervention and decreasing body fat promoted beneficial cardiovascular factors.

Triglyceride-glucose index is associated with metabolic syndrome in women with polycystic ovary syndrome

OBJECTIVE

To explore the correlation of triglyceride-glucose index (TyG) index with metabolic syndrome (MetS) and metabolic risk factors, and to assess the predictive value of TyG for MetS in women with PCOS.

METHODS

This is a retrospective cross-sectional study that included 819 women diagnosed with PCOS and 3122 women without PCOS from January 2018 to December 2021. The definition of MetS adopted in this study was the International Diabetes Federation (IDF) criteria. The TyG index was calculated as the ln (fasting triglyceride level [mg/dL] × fasting glucose level [mg/dL]/2).

RESULTS

MetS was diagnosed in 266 women (32.5%) among 819 subjects with PCOS, and in 287 women (9.2%) among 3122 subjects without PCOS. Logistic regression analysis showed that women in the highest tertile of TyG index had the highest prevalence of MetS (OR = 3.66, 95%CI: 1.28-10.49) after adjusting for confounding factors. Compared with the lowest tertile, PCOS women in the highest tertile showed the highest odds ratio of hypertension, obesity, central obesity, hyperglycemia and dyslipidemia. Furthermore, TyG index was able to identify MetS in women with PCOS, and the optimal cutoff values were 8.65 (Youden index = 0.65).

CONCLUSION

TyG index was positively and independently correlated with the prevalence of MetS, which also indicated a good predictive ability in women with PCOS.

Association between Metabolic Syndrome and Leukocytes: Systematic Review and Meta-Analysis

Background: Metabolic syndrome (MetS) is a group of metabolic abnormalities characterised by central obesity, hypertension, dyslipidaemia, and dysregulation of blood glucose, which is associated with the risk of diabetes, cardiovascular disease, and overall mortality. White blood cell count is a selective marker of acute infection and inflammation, which could provide information on the metabolic status of subjects. This study aims to provide the best evidence on the association between MetS and white blood cell count by determining the effect size of this biomarker. Methods: A systematic review and meta-analysis of studies indexed in the PubMed and Scopus databases were performed. Methodological quality was assessed using the STROBE tool, overall risk of bias using RevMan (Cochrane Collaboration), and quality of evidence using Grade Pro. Results: We included 14 articles comparing leukocyte concentrations in 21,005 subjects with MetS and 66,339 controls. Subjects with MetS had a higher mean leukocyte count, 0.64 cells ×109/L; CI95% 0.55-0.72; p < 0.00001; I2 = 93%. Conclusions: An in-depth evaluation of the relationship of leukocytes in the pathophysiological process of MetS could lead to new insights into early diagnosis.

Effects of curcumin/turmeric supplementation on glycemic indices in adults: A grade-assessed systematic review and dose-response meta-analysis of randomized controlled trials

INTRODUCTION

Glycemic control is of utmost importance both as a preventive measure in individuals at risk of diabetes and in the management of patients with disturbed glycemia. Turmeric/curcumin has been extensively studied in this field. In the present systematic review and meta-analysis, we aimed at investigating the impact of turmeric/curcumin supplementation on glycemic control.

METHODS

Major online databases (PubMed, Scopus, Web of Science, Cochrane Library and Google Scholar) were systematically searched from inception up to October 2022. Relevant randomized controlled trials (RCTs) meeting our eligible criteria were included. Weighted mean differences (WMDs) with confidence intervals (CIs) were expressed using a random-effect model. Subgroup analyses were conducted to find the sources of heterogeneities. To detect risk of bias in the included studies, we used the Cochrane risk-of-bias tool. The registration number was CRD42022374874.

RESULTS

Out of 4182 articles retrieved from the initial search, 59 RCTs were included. Our findings suggested that turmeric/curcumin supplementation was significantly effective in improving fasting blood sugar (WMD: 4.60 mg/dl; 95% CI: 5.55, -3.66), fasting insulin levels (WMD: 0.87 μIU/ml; 95% CI: 1.46, -0.27), hemoglobin A1c (HbA1c) (WMD: 0.32%; 95% CI: 0.45, -0.19), and homeostatic model assessment of insulin resistance (HOMA-IR) (WMD: 0.33; 95% CI: 0.43, -0.22).

CONCLUSION

Our results indicate that turmeric/curcumin supplementation can be considered as a complementary method in the management of disturbed glycemia.

Is Increasing Diet Diversity of Animal-Source Foods Related to Better Health-Related Quality of Life among Chinese Men and Women?

Diet plays a crucial role in regulating individuals' lifestyles and is closely related to health. The intake of animal-sourced foods (ASF) provides the human body with high-quality protein and various micronutrients. This study aimed to investigate whether the diversity of animal foods has a positive impact on the health-related quality of life (HRQoL) among residents. The data came from the Shaanxi baseline survey of the Northwest Chinese Regional Ethnic Cohort Study, which recruited more than 100 thousand participants aged 35 to 74 from five provinces between June 2018 and May 2019. A total of 39,997 participants in Shaanxi (mean age: 50 years; 64% women) were finally included in this current study. The animal source food diet diversity score (ASFDDS) was established based on the frequency of consuming pork, mutton, beef, poultry, seafood, eggs, pure milk, and yogurt. The physical component score (PCS) and mental component score (MCS), ranging from 0 to 100 on the 12-Item Short Form Survey (SF-12), were used to assess participants' HRQoL. Better PCS/MCS was defined as scores higher than the 90th percentile. The results showed that men had a higher intake of ASF and ASFDDS than women. After adjusting for potential confounders, compared with those who never or rarely consumed animal foods, the likelihood of having better PCS and MCS increased by 16% (OR = 1.16, 95%CI: 1.01-1.34) and 24% (OR = 1.24, 95%CI: 1.03-1.448), respectively, in men with an ASFDDS ≥ 2. In women, a 34% increase (OR = l.34, 95%CI: 116-l.54) likelihood for better PCS was observed for an ASFDDS ≥ 2, but no association was observed for MCS. Increasing each specific animal source's food intake was associated with better PCS after adjusting for all covariates. However, for MCS, positive associations were only observed in seafood consumption among men and eggs among women. Restricted cubic splines showed a substantial dose-response association between intake frequency of animal-source foods and PCS, both in men and women. The study suggests that a diverse intake of animal-sourced foods can potentially improve the HRQoL of Chinese adults.

Gender Differences in Insulin Resistance: New Knowledge and Perspectives

Insulin resistance is the main mechanism in a whole series of pathological conditions, which are not only of metabolic interest but also of a systemic type. This phenomenon means that the body's cells become less sensitive to the hormone insulin, leading to higher levels of insulin in the blood. Insulin resistance is a phenomenon that can be found in both men and women and in particular, in the latter, it is found mainly after menopause. Premenopause, hormonal fluctuations during the menstrual cycle, and the presence of estrogen can affect insulin sensitivity. Androgens, such as testosterone, are typically higher in men and can contribute to insulin resistance. In both sexes, different human body types affect the distribution and location of body fat, also influencing the development of diabetes and cardiovascular disease. Insulin resistance is also associated with some neurological and neurogenerative disorders, polycystic ovary syndrome, atherosclerosis, and some of the main neoplastic pathologies. A healthy lifestyle, including regular physical activity, a balanced diet, and self-maintenance, can help to prevent the onset of insulin resistance, regardless of gender, although the different habits between men and women greatly affect the implementation of preventative guidelines that help in fighting the manifestations of this metabolic disorder. This review may help to shed light on gender differences in metabolic diseases by placing a necessary focus on personalized medical management and by inspiring differentiated therapeutic approaches.

Cannabinoformins: Designing Biguanide-Embedded, Orally Available, Peripherally Selective Cannabinoid-1 Receptor Antagonists for Metabolic Syndrome Disorders

We have designed orally bioavailable, non-brain-penetrant antagonists of the cannabinoid-1 receptor (CB1R) with a built-in biguanide sensor to mimic 5'-adenosine monophosphate kinase (AMPK) activation for treating obesity-associated co-morbidities. A series of 3,4-diarylpyrazolines bearing rational pharmacophoric pendants designed to limit brain penetration were synthesized and evaluated in CB1R ligand binding assays and recombinant AMPK assays. The compounds displayed high CB1R binding affinity and potent CB1R antagonist activities and acted as AMPK activators. Select compounds showed good oral exposure, with compounds 36, 38-S, and 39-S showing <5% brain penetrance, attesting to peripheral restriction. In vivo studies of 38-S revealed decreased food intake and body weight reduction in diet-induced obese mice as well as oral in vivo efficacy of 38-S in ameliorating glucose tolerance and insulin resistance. The designed "cannabinoformin" four-arm CB1R antagonists could serve as potential leads for treatment of metabolic syndrome disorders with negligible neuropsychiatric side effects.

Concurrence of hyperinsulinemia and hyperuricemia significantly augmented all-cause mortality

BACKGROUND AND AIMS

Hyperinsulinemia and hyperuricemia are known to increase the risk of mortality due to certain complications, such as Type 2 Diabetes and cardiovascular disease. However, despite their common comorbidities, their combined effect has not been evaluated. The study's aim was to evaluate the combine effect of hyperinsulinemia and hyperuricemia on all-cause mortality.

METHODS AND RESULTS

NHANES datasets (cycles 2003-2018) were examined. Differences between groups were evaluated using Rao-Scott Chi-square and General Linear Model for categorical and continuous data, respectively. Hazard Ratios (HR) were calculated using Cox regression with 95% confidence intervals (95%CI). There was significant difference (p < 0.05) in the mortality rate between the control group (2.3 ± 0.2%), the hyperinsulinemia only group (3.1 ± 0.3%), the hyperuricemia only group (4.0 ± 0.8%), and both conditions (5.1 ± 0.8%). Individually, when compared to the control group, there was a significant increase in mortality risk for hyperinsulinemia (HR: 1.50, 95%CI: 1.12-2.01, p = 0.007) and hyperuricemia (HR: 1.80, 95%CI:1.18-2.75, p = 0.006). However, when both conditions were present, there appeared an additive effect in the mortality risk (HR: 2.32, 95%CI: 1.66-3.25, p < 0.001). When stratified by BMI class, only normal weight participants presented with a significant risk (HR: 7.00, 95%CI: 2.50-20.30, p < 0.001). Also, when stratified by age, only participants older than 40 years presented a risk (HR: 2.22, 95%CI: 1.56-3.16, p < 0.001).

CONCLUSION

Alone, hyperuricemia and hyperinsulinemia significantly increased the mortality rate; however, the combined presence of both pathologies was associated with a significantly augmented mortality rate. Normal weight participant or that were >40 years old had a greater risk for mortality.

Handgrip Strength Is Associated with Specific Aspects of Vascular Function in Individuals with Metabolic Syndrome

BACKGROUND

Metabolic syndrome (MetS) is a disorder associated with an increased risk for the development of diabetes mellitus and its complications. Lower isometric handgrip strength (HGS) is associated with an increased risk of cardiometabolic diseases. However, the association between HGS and arterial stiffness parameters, which are considered the predictors of morbidity and mortality in individuals with MetS, is not well defined.

OBJECTIVE

To determine the association between HGS and HGS asymmetry on components of vascular function in adults with MetS.

METHODS

We measured handgrip strength normalized to bodyweight (HGS/kg), HGS asymmetry, body composition, blood glucose, lipid profile, blood pressure, pulse wave velocity (PWV), reflection coefficient (RC), augmentation index @75 bpm (AIx@75) and peripheral vascular resistance (PVR) in 55 adults with a diagnosis of MetS between 25 and 54 years old.

RESULTS

Mean age was 43.1 ± 7.0 years, 56.3% were females. HGS/kg was negatively correlated with AIx@75 (r = -0.440), p < 0.05, but these associations were not significant after adjusting for age and sex. However, when interaction effects between sex, HGS/kg and age were examined, we observed an inverse relationship between HGS/kg and AIx@75 in the older adults in the sample, whereas in the younger adults, a weak direct association was found. We also found a significant association between HGS asymmetry and PVR (beta = 30, 95% CI = 7.02; 54.2; p <0.012).

CONCLUSIONS

Our findings suggest that in people with MetS, maintaining muscle strength may have an increasingly important role in older age in the attenuation of age-related increases in AIx@75-a marker of vascular stiffness-and that a higher HGS asymmetry could be associated with a greater vascular resistance.

Prevalence of insulin resistance in Chinese solar greenhouse and field workers: evidence from a solar greenhouse and field workers study

Evidence suggests that agricultural workers are at higher risk of insulin resistance (IR), but few studies have investigated IR in solar greenhouse workers, who are exposed to higher concentrations of agricultural risk factors than traditional agricultural workers. A prevalence study was conducted in a greenhouse vegetable farm in China. In total, 948 participants were enrolled in this study. Among them, 721 participants were allocated to the greenhouse worker group (G group), and 227 participants were assigned to the field worker group (F group). The TyG index, which is an indicator to evaluate prediabetes (IR), was calculated by the formula: TyG index = ln [fasting triglycerides (mg/dL) × fasting plasma glucose (mg/dL)/2]. To evaluate the associations of TyG index alternation with solar greenhouse and field work, multiple linear regression (MLR) and logistic regression models were performed. The TyG index in the G group (8.53 ± 0.56) was higher than that in the F group (8.44 ± 0.59) (p < 0.05). Solar greenhouse work was positively associated with an increased TyG index in both the multiple linear regression model [β = 0.207, (0.006, 0.408)] and the logistic regression model [OR = 1.469, (1.070, 2.016)]. IR was associated with the solar greenhouse work. However, the determination of agricultural hazard factors needs to be further strengthened to improve exposure assessment. Graphical Abstract.

Effect of Insulin Resistance on Recurrence after Radiofrequency Catheter Ablation in Patients with Atrial Fibrillation

BACKGROUND

Whether there are many risk factors for recurrence of atrial fibrillation (AF) after ablation is unclear. The aim of this study was to investigate the relationship between insulin resistance (IR) and AF recurrence in patients without diabetes who underwent catheter ablation.

METHODS

This retrospective study included patients who underwent AF ablation between 2018 and 2019 at the First Affiliated Hospital of Zhengzhou University. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated, and a value of ≥2.69 was defined as IR. The patients were divided into two groups (group 1 HOMA-IR < 2.69, n = 163; group 2 HOMA-IR ≥ 2.69, n = 69). AF recurrence was defined as the occurrence of atrial arrhythmias of more than 30 s after the first 3 months. Univariate and multivariable Cox regression models were used to analyse the risk of AF recurrence.

RESULTS

Overall, 232 patients were enrolled (mean age, 59.9 ± 10.2 years old; female, 37.5%; paroxysmal AF, 71.6%). We found that dyslipidaemia, antiarrhythmic drug use, fasting blood glucose and fasting insulin were significantly higher in the IR group (P < 0.05). During the follow-up 1 year after ablation, 62 (26.7%) patients experienced AF recurrence. After adjusting for traditional risk factors, multivariable analysis showed that the HOMA-IR value (HR 1.259, 95% CI 1.086-1.460, P = 0.002) and left atrial diameter (LAD; HR 1.043, 95% CI 1.005-1.083, P = 0.026) were independently associated with AF recurrence.

CONCLUSIONS

The present results provide evidence that IR patients are more likely to experience AF recurrence. Improving IR status may be a potential target for reducing the postoperative recurrence rate.

Improved Insulin Secretion Response and Beta-cell Function Correlated with Increased Prolactin Levels After Laparoscopic Sleeve Gastrectomy in Morbidly Obese Patients with Acanthosis Nigricans

OBJECTIVE

To explore insulin secretion patterns, β-cell function, and serum prolactin (PRL) concentrations in Chinese morbidly obese patients with Acanthosis nigricans (AN) and their alterations after laparoscopic sleeve gastrectomy (LSG).

METHODS

A total of 138 morbidly obese subjects undergoing LSG were categorized as simple obesity without AN (OB group, n = 55) and obesity with AN (AN group, n = 83). Oral glucose tolerance test (OGTT), PRL, and related metabolic indices were performed pre- and 12 months post-LSG. Insulin secretion patterns were derived from insulin secretion peak time during OGTT: type I (peak at 30 or 60 min) and type II (peak at 120 or 180 min).

RESULTS

Preoperatively, AN group showed significantly higher proportions of type II insulin secretion pattern, fasting insulin (FINS), and homeostatic model assessment of insulin resistance (HOMA-IR) whereas lower oral glucose insulin sensitivity (OGIS), insulinogenic index (IGI), and disposition index (DI) than OB group, which were improved significantly at 12 months postoperatively in both groups, more pronounced in AN group. Intriguingly, serum PRL declined substantially in AN group than OB group at baseline whereas elevated only in the AN group post-LSG. After adjusting for confounding factors, elevated PRL correlated significantly with increased IGI and DI, and decreased HOMA-IR in both genders, as well as increased OGIS in females, which was detected only in the AN group CONCLUSION: Morbidly obese patients with AN presented delayed insulin secretion response, impaired insulin secretion, and β-cell dysfunction, which were significantly improved by LSG and might benefit from elevated PRL.

Predicting metabolic syndrome by obesity- and lipid-related indices in mid-aged and elderly Chinese: a population-based cross-sectional study

Objective

To predict the optimal cut-off values for screening and predicting metabolic syndrome(MetS) in a middle-aged and elderly Chinese population using 13 obesity and lipid-related indicators, and to identify the most suitable predictors.

Methods

The data for this cross-sectional investigation came from the China Health and Retirement Longitudinal Study (CHARLS), including 9457 middle-aged and elderly people aged 45-98 years old. We examined 13 indicators, including waist circumference (WC), body mass index (BMI), waist-height ratio (WHtR), visceral adiposity index (VAI), a body shape index (ABSI), body roundness index (BRI), lipid accumulation product index (LAP), conicity index (CI), Chinese visceral adiposity index (CVAI), triglyceride-glucose index (TyG-index) and their combined indices (TyG-BMI, TyG-WC, TyG-WHtR). The receiver operating characteristic curve (ROC) was used to determine the usefulness of indicators for screening for MetS in the elderly and to determine their cut-off values, sensitivity, specificity, and area under the curve (AUC). Association analysis of 13 obesity-related indicators with MetS was performed using binary logistic regression analysis.

Results

A total of 9457 middle-aged and elderly Chinese were included in this study, and the overall prevalence of the study population was 41.87% according to the diagnostic criteria of NCEP ATP III. According to age and gender, the percentage of males diagnosed with MetS was 30.67% (45-54 years old: 30.95%, 55-64 years old: 41.02%, 65-74 years old: 21.19%, ≥ 75 years old: 6.84%). The percentage of females diagnosed with MetS was 51.38% (45-54 years old: 31.95%, 55-64 years old: 39.52%, 65-74 years old: 20.43%, ≥ 75 years old: 8.10%). The predictive power of Tyg-related parameters was more prominent in both sexes. In addition, LAP and CVAI are also good at predicting MetS. ABSI had a poor prediction ability.

Conclusions

Among the middle-aged and elderly population in China, after adjusting for confounding factors, all the indicators except ABSI had good predictive power. The predictive power of Tyg-related parameters was more prominent in both sexes. In addition, LAP and CVAI are also good at predicting MetS.

Valproate-Induced Metabolic Syndrome

Valproic acid (VPA) and its salts (sodium calcium magnesium and orotic) are psychotropic drugs that are widely used in neurology and psychiatry. The long-term use of VPA increases the risk of developing adverse drug reactions (ADRs), among which metabolic syndrome (MetS) plays a special role. MetS belongs to a cluster of metabolic conditions such as abdominal obesity, high blood pressure, high blood glucose, high serum triglycerides, and low serum high-density lipoprotein. Valproate-induced MetS (VPA-MetS) is a common ADR that needs an updated multidisciplinary approach to its prevention and diagnosis. In this review, we consider the results of studies of blood (serum and plasma) and the urinary biomarkers of VPA-MetS. These metabolic biomarkers may provide the key to the development of a new multidisciplinary personalized strategy for the prevention and diagnosis of VPA-MetS in patients with neurological diseases, psychiatric disorders, and addiction diseases.

Qidan Tiaozhi capsule attenuates metabolic syndrome via activating AMPK/PINK1-Parkin-mediated mitophagy

ETHNOPHARMACOLOGICAL RELEVANCE

Qidan Tiaozhi capsule (QD), a traditional Chinese medicine, has been used to treat metabolic syndrome for over a decade. However, the mechanism of QD in the treatment of metabolic syndrome is still unknown.

AIM OF THE STUDY

Growing studies demonstrate that impaired mitophagy is one of the important causes of metabolic syndrome. Thus, this research aims to investigate the mechanism of mitophagy in the QD treatment of metabolic syndrome.

MATERIALS AND METHODS

Network pharmacology and molecular docking were used to probe the mechanism of QD treatment of metabolic syndrome. In an oleic acid-induced cell model, glucose consumption and uptake capacity, triglyceride (TG), total cholesterol (TC), malonaldehyde (MDA), superoxide dismutase (SOD) and ROS levels, and mitochondrial membrane potential (MMP) were examined. mRFP-GFP-LC3 adenovirus and GFP-LC3 lentivirus were used to examine the effect of QD on mitophagy. The IRS2-PI3K and AMPK/PINK1-Parkin signal pathways were also determined. What's more, the PINK1 gene was silenced to verify the above findings. In a high-fat diet-fed mouse model, body weight, organ indexes, OGTT, ITT, HOMA-IR, insulin sensitivity, serum MDA, SOD, TC, TG, LDL-C and HDL-C, hepatic TC, TG, LDL-C and HDL-C levels, hepatic steatosis, and IRS2-PI3K and AMPK/PINK1-Parkin signal pathways were investigated.

RESULTS

Results from network pharmacology and molecular docking suggested that QD might suppress oxidative stress to improve metabolic syndrome. In an oleic acid-induced cell model, compared with the model group, enhanced glucose consumption and uptake ability, inhibited intracellular lipid accumulation, TC, TG, MDA and ROS levels, and increased SOD level and MMP were found in QD groups. And mitophagy levels, IRS2-PI3K and AMPK/PINK1-Parkin signal pathways were promoted. Interestingly, PINK1 silencing reversed the therapeutic action of QD on oleic acid-induced cells. In high-fat diet-fed mice, inhibited body weight, abdominal fat indexes, liver indexes, HOMA-IR, serum and hepatic TC, TG and LDL-C, serum MDA and hepatic steatosis, and increased insulin sensitivity, serum and hepatic HDL-C, serum SOD, and activated IRS2-PI3K and AMPK/PINK1-Parkin signal pathways were found in QD groups.

CONCLUSION

QD activates AMPK/PINK1-Parkin-mediated mitophagy to suppress oxidative stress to treat metabolic syndrome.

Efficiency comparison of an isoeugenol-derivated compound, eugenosedin-A, with glibenclamide and pioglitazone in protecting cardiovascular dysfunction of diabetic SHR

This study was to investigate three agents possible protective effect against DM-induced cardiovascular dysfunction in spontaneously hypertensive rats (SHR). Control group was fed normal diet, DM group was injected with STZ/NA and fed high fat diet (HFD), and treatment groups were given STZ/NA, fed HFD, and then oral gavaged with eugenosedin-A (Eu-A), glibenclamide (Gli), or pioglitazone (Pio) 5 mg/kg/per day for 4-week, respectively. Eu-A, Gli, and Pio clearly ameliorated the changes of body weight, cardiac weight, and the biochemical parameters, cardiovascular disorders and inflammation. Like Gli and Pio, Eu-A may be effectively to control DM and the cardiovascular dysfunction.

Metabolic Syndrome and Clinical Outcomes of Patients with Gastric Cancer: A Meta-Analysis

Metabolic syndrome (MetS) is suggested to participate in the pathogenesis and progress of some cancers via inducing low-grade systemic inflammation. However, the influence of MetS on patients with gastric cancer (GC) remains not fully determined. A systematic review and meta-analysis was therefore performed to evaluate the influence of MetS on clinical outcomes of patients with GC. A search of PubMed, Embase, Web of Science, Wanfang, and CNKI retrieved relevant cohort studies from the inception of the databases to October 11, 2022. We pooled the results using a random-effects model that incorporates heterogeneity. In the meta-analysis, 6649 patients with GC were included, and all of them received gastrectomy. A total of 1248 (18.8%) patients had MetS at baseline. Pooled results showed that MetS was associated with higher risks of postoperative complications [risk ratio (RR): 2.41, 95% confidence interval (CI): 1.85 to 3.14, p<0.001; I2=55%], overall mortality (RR: 1.73, 95% CI: 1.85 to 3.14, p<0.001; I2=77%), and recurrence of GC (RR: 2.00, 95% CI: 1.10 to 3.63, p=0.02; I2=39%). Subgroup analyses showed similar results in prospective and retrospective cohort studies and in studies with MetS diagnosed with the Chinese Diabetes Society criteria and the National Cholesterol Education Program Adult Treatment Panel III criteria (p for subgroup difference all>0.05). In patients with GC after gastrectomy, MetS may be a predictor of high incidence of postoperative complications, cancer recurrence, and overall mortality.

High-carbohydrate and fat diet consumption causes metabolic deterioration, neuronal damage, and loss of recognition memory in rats

The number of people diagnosed with metabolic syndrome (MetS) has increased dramatically to reach alarming proportions worldwide. The origin of MetS derives from bad eating habits and sedentary lifestyle. Most people consume foods high in carbohydrates and saturated fat. In recent years, it has been reported that alterations in insulin at the brain level could have an impact on the appearance of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, dementia, depression, and other types of disorders that compromise brain function. These alterations have been associated with damage to the structure and function of neurons located in the reptilian and limbic systems, a decrease in dendritic arborization and an exacerbated inflammatory state that impaired learning and memory and increased in the state of stress and anxiety. Although the molecular mechanisms induced by MetS to cause neurodegeneration are not fully understood. The aim of this study is to know the effect of the intake of hypercaloric diets on the structure and function of neurons located in the frontal cortex, hypothalamus and hippocampus and its impact on behavior in rats with metabolic syndrome. In conclusion, the present study illustrated that chronic exposure to hypercaloric diets, with a high content of sugars and saturated fatty acids, induces a proinflammatory state and exacerbates oxidative stress in brain regions such as the hypothalamus, hippocampus, and frontal cortex, leading to dysfunction. metabolism, neuronal damage, and recognition memory loss.

The Crosstalk between Gut Microbiota and White Adipose Tissue Mitochondria in Obesity

Adipose tissue (AT) dysregulation is a key process in the pathophysiology of obesity and its cardiometabolic complications, but even if a growing body of evidence has been collected over recent decades, the underlying molecular basis of adiposopathy remains to be fully understood. In this context, mitochondria, the intracellular organelles that orchestrate energy production and undergo highly dynamic adaptive changes in response to changing environments, have emerged as crucial regulators of both white (WAT) and brown adipose tissue (BAT) metabolism and function. Given that the gut microbiota and its metabolites are able to regulate host metabolism, adipogenesis, WAT inflammation, and thermogenesis, we hypothesize that their frequently observed dysregulation in obesity could affect AT metabolism by exerting direct and indirect effects on AT mitochondria. By collecting and revising the current evidence on the connections between gut microbiota and AT mitochondria in obesity, we gained insights into the molecular biology of their hitherto largely unexplored crosstalk, tracing how gut microbiota may regulate AT mitochondrial function.

Multifunctional nanoparticles with anti-inflammatory effect for improving metabolic syndromes

Metabolic syndromes are a group of metabolic disorders for which the molecular mechanisms are still unclear. An increasing number of studies have implicated metabolic syndrome in the association with inflammation. Currently, lipsomes is known to improve nanoparticle hydrophobicity. Meanwhile, in drug delivery systems the application of cholesterol, which is commonly used to stabilise liposomal structures, has essentially no pharmacological effect on liposomes. Herein, we developed an 'anti-inflammatory liposome' (Phy-Lip) to effectively handle these challenges via employing Phytosterol instead of cholesterol. Different with the conventional liposomes, Phy-Lip is a much more brilliant nanoparticle with anti-inflammatory functions. In Phy-Lip, cholesterol was substituted by Phy, which works as membrane stabiliser, anti-inflammatory adjuvant at the same time. The experimental results show that Phy-Lip has a strong anti-inflammatory effect, and improves Metabolic syndromes. This study aims to provide a way to solve the challenge.

Value of the triglyceride-glucose index and non-traditional blood lipid parameters in predicting metabolic syndrome in women with polycystic ovary syndrome

PURPOSE

Insulin resistance (IR) is common in patients with polycystic ovary syndrome (PCOS). Metabolic syndrome (MS) includes, inter alia, IR, hypertension, dyslipidemia, and disturbances in glucose metabolism. The triglyceride-glucose (TyG) index and non-traditional lipid parameters are strong predictors of IR and cardiovascular disease and can be considered as screening indicators for MS. This study aimed to evaluate the predictive potential of non-traditional lipid parameters and the TyG index to identify MS in PCOS.

METHODS

This cross-sectional study included 134 women diagnosed with PCOS (50 patients with comorbid MS and 84 patients without MS). Biochemical indices were collected, and triglycerides (TG)/high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC)/HDL-C, low-density lipoprotein cholesterol (LDL-C)/HDL-C, non-HDL-C, TyG, and TyG-BMI indices were calculated. Logistic regression analysis was used to compare and determine the association of the six parameters with MS, and the receiver operating characteristic (ROC) curve was used to evaluate the performance of each parameter in identifying MS in the PCOS population.

RESULTS

After adjusting for age and body mass index (BMI), TG/HDL-C, TC/HDL-C, LDL-C/HDL-C, non-HDL-C, TyG, and TyG-BMI were associated with MS (all P<0.05). The odds ratios were 4.075 (0.891, 1.107), 3.121 (1.844, 5.282), 3.106 (1.734, 5.561), 2.238 (1.302, 3.848), 13.422 (4.364, 41.282), and 1.102 (1.056, 1.150), respectively. TG/HDL-C, TC/HDL-C, LDL-C/HDL-C, non-HDL-C, TyG, and TyG-BMI are effective predictors of MS in PCOS, and their cut-off values can be used for the early detection of MS. TyG-BMI had the strongest performance in predicting MS (area under the curve 0.905, 95% CI 0.855-0.956), and its optimal critical value for predicting MS was 202.542.

CONCLUSIONS

TG/HDL-C, TC/HDL-C, LDL-C/HDL-C, non-HDL-C, TyG, and TyG-BMI are novel, clinically convenient and practical markers for the early identification of MS risk in PCOS patients.

Obesity- and lipid-related indices as a predictor of obesity metabolic syndrome in a national cohort study

Objective

Metabolic syndrome is a common condition among middle-aged and elderly people. Recent studies have reported the association between obesity- and lipid-related indices and metabolic syndrome, but whether those conditions could predict metabolic syndrome is still inconsistent in a few longitudinal studies. In our study, we aimed to predict metabolic syndrome by obesity- and lipid-related indices in middle-aged and elderly Chinese adults.

Method

A national cohort study that consisted of 3,640 adults (≥45 years) was conducted. A total of 13 obesity- and lipid-related indices, including body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), conicity index (CI), visceral adiposity index (VAI), Chinese visceral adiposity index (CVAI), lipid accumulation product (LAP), a body shape index (ABSI), body roundness index (BRI), and triglyceride glucose index (TyG-index) and its correlation index (TyG-BMI, TyG-WC, and TyG-WHtR), were recorded. Metabolic syndrome (MetS) was defined based on the criteria of the National Cholesterol Education Program Adult Treatment Panel III (2005). Participants were categorized into two groups according to the different sex. Binary logistic regression analyses were used to evaluate the associations between the 13 obesity- and lipid-related indices and MetS. Receiver operating characteristic (ROC) curve studies were used to identify the best predictor of MetS.

Results

A total of 13 obesity- and lipid-related indices were independently associated with MetS risk, even after adjustment for age, sex, educational status, marital status, current residence, history of drinking, history of smoking, taking activities, having regular exercises, and chronic diseases. The ROC analysis revealed that the 12 obesity- and lipid-related indices included in the study were able to discriminate MetS [area under the ROC curves (AUC > 0.6, P < 0.05)] and ABSI was not able to discriminate MetS [area under the ROC curves (AUC < 0.6, P > 0.05)]. The AUC of TyG-BMI was the highest in men, and that of CVAI was the highest in women. The cutoff values for men and women were 187.919 and 86.785, respectively. The AUCs of TyG-BMI, CVAI, TyG-WC, LAP, TyG-WHtR, BMI, WC, WHtR, BRI, VAI, TyG index, CI, and ABSI were 0.755, 0.752, 0.749, 0.745, 0.735, 0.732, 0.730, 0.710, 0.710, 0.674, 0.646, 0.622, and 0.537 for men, respectively. The AUCs of CVAI, LAP, TyG-WC, TyG-WHtR, TyG-BMI, WC, WHtR, BRI, BMI, VAI, TyG-index, CI, and ABSI were 0.687, 0.674, 0.674, 0.663, 0.656, 0.654, 0.645, 0.645, 0.638, 0.632, 0.607, 0.596, and 0.543 for women, respectively. The AUC value for WHtR was equal to that for BRI in predicting MetS. The AUC value for LAP was equal to that for TyG-WC in predicting MetS for women.

Conclusion

Among middle-aged and older adults, all obesity- and lipid-related indices, except ABSI, were able to predict MetS. In addition, in men, TyG-BMI is the best indicator to indicate MetS, and in women, CVAI is considered the best hand to indicate MetS. At the same time, TyG-BMI, TyG-WC, and TyG-WHtR performed better than BMI, WC, and WHtR in predicting MetS in both men and women. Therefore, the lipid-related index outperforms the obesity-related index in predicting MetS. In addition to CVAI, LAP showed a good predictive correlation, even more closely than lipid-related factors in predicting MetS in women. It is worth noting that ABSI performed poorly, was not statistically significant in either men or women, and was not predictive of MetS.

Thiourea derivatives inhibit key diabetes-associated enzymes and advanced glycation end-product formation as a treatment for diabetes mellitus

This study was designed to screen novel thiourea derivatives against different enzymes, such as α-amylase, α-glucosidase, protein tyrosine phosphatase 1 B, and advanced glycated end product (AGEs). A cytotoxicity analysis was performed using rat L6 myotubes and molecular docking analysis was performed to map the binding interactions between the active compounds and α-amylase and α-glucosidase. The data revealed the potency of five compounds, including E (1-(2,4-difluorophenyl)-3-(3,4-dimethyl phenyl) thiourea), AG (1-(2-methoxy-5-(trifluoromethyl) phenyl)-3-(3-methoxy phenyl) thiourea), AF (1-(2,4-dichlorophenyl)-3-(4-ethylphenyl) thiourea), AD (1-(2,4-dichlorophenyl)-3-(4-ethylphenyl) thiourea), and AH (1-(2,4-difluorophenyl)-3-(2-iodophenyl) thiourea), showed activity against α-amylase. The corresponding percentage inhibitions were found to be 85 ± 1.9, 82 ± 0.7, 75 ± 1.2, 72 ± 0.4, and 65 ± 1.1%, respectively. These compounds were then screened using in vitro assays. Among them, AH showed the highest activity against α-glucosidase, AGEs, and PTP1B, with percentage inhibitions of 86 ± 0.4% (IC₅₀  = 47.9 μM), 85 ± 0.7% (IC₅₀  = 49.51 μM), and 85 ± 0.5% (IC₅₀  = 79.74 μM), respectively. Compound AH showed an increased glucose uptake at a concentration of 100 μM. Finally, an in vivo study was conducted using a streptozotocin-induced diabetic mouse model and PTP1B expression was assessed using real-time PCR. Additionally, we examined the hypoglycemic effect of compound AH in diabetic rats compared to the standard drug glibenclamide.

A systematic review on anti-diabetic plant essential oil compounds: Dietary sources, effects, molecular mechanisms, and safety

Type 2 diabetes mellitus (T2DM) is a multifaceted metabolic syndrome defined through the dysfunction of pancreatic β-cells driven by a confluence of genetic and environmental elements. Insulin resistance, mediated by interleukins and other inflammatory elements, is one of the key factors contributing to the progression of T2DM. Many essential oils derived from dietary plants are beneficial against various chronic diseases. We reviewed the anti-diabetic properties of dietary plant-derived essential oil compounds, with a focus on their molecular mechanisms by modulating specific signaling pathways and other critical inflammatory mediators involved in insulin resistance. High-quality literature published in the last 12 years, from 2010 to 2022, was collected from the Scopus, Web of Science, PubMed, and Embase databases using the search terms "dietary plants," "essential oils," "anti-diabetic," "insulin resistance," "antihyperglycemic," "T2DM," "anti-diabetic essential oils," and anti-diabetic mechanism." According to the results, the essential oil compounds, including cinnamaldehyde, carvacrol, zingerone, sclareol, zerumbone, myrtenol, thujone, geraniol, citral, eugenol, thymoquinone, thymol, citronellol, α-terpineol, and linalool have been demonstrated to contain strong anti-diabetic effects via modulating various signal transduction pathways linked to glucose metabolism. Additionally, in diabetes-related animal models, they can also considerably reduce the expression of TNF-α, IL-1β, IL-4, IL-6, iNOS, and COX-2. The main signaling molecules regulated by these compounds include AMPK, GLUT4, Caspase-3, PPARγ, PPARα, NF-κB, p-IκBα, MyD88, MCP-1, SREBP-1c, AGEs, RAGE, VEGF, Nrf2/HO-1, and SIRT-1. They can also significantly inhibit the generation of TBARS and MDA, reduce oxidative stress, increase insulin levels, adiponectin, and glycoprotein enzymes, boost antioxidant enzymes like SOD, CAT, and GPx, as well as reduce glutathione and vital glycolytic enzymes. Besides, they can significantly lower the levels of liver enzymes and lipid profile markers. Moreover, most essential oil compounds are generally safe based on animal studies. In conclusion, dietary plant-derived essential oil compounds have potential anti-diabetic effects by influencing different signaling pathways and molecular targets linked to glucose metabolism, and should be safe and beneficial against diabetes and related complications.

Meta-analysis of the intervention effects of taekwondo on metabolic syndrome indicators

Objective: To quantify the effect of taekwondo as an intervention on the indicators of metabolic syndrome and identify an intervention plan with the optimal effects. Methods: Combining the Cnki.net, Wanfang, PubMed, Web of Science, Embase, KISS, RISS, and DBPIA databases, this paper retrieved relevant references in Chinese, English, and Korean, applied Review Manager 5.4 software to evaluate the methodological quality of the included references according to the Cochrane manual, and utilized Comprehensive Meta-Analysis version 3.7 to perform statistical analyses. Result: A total of 45 references and 1079 related subjects were included in the analysis. The results of the meta-analysis showed that taekwondo has a beneficial effect on all indicators of metabolic syndrome (Hedges' g [effect size] = -0.615, -0.672, -0.497, -0.785, -0.591, and 0.435; p < 0.05). Subgroup analysis revealed the superior intervention effect of taekwondo on metabolic syndrome in women compared to men, middle-aged and elderly compared to other age groups, and abnormal metabolic syndrome indicators compared to normal values. Moreover, the best results were obtained for longer intervention durations-12 weeks-three times per week, for 40-50 min per session. In addition, the combination of intervention types (poomsae, kick, and taekwondo gymnastics) showed optimal effects. The exercise intensity should consider the characteristics of the intervention object and be generally set to medium or high intensity. Conclusion: Taekwondo can effectively improve metabolic syndrome, as evidenced by decreased body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), and triglyceride (TG) levels and increased high-density lipoprotein cholesterol (HDL-C) level. Taekwondo had the greatest effect on quinquagenarian women with abnormal levels of metabolic syndrome indicators. To maximize the intervention effect of taekwondo on metabolic syndrome, an exercise prescription of high-intensity poomsae, kick, and taekwondo gymnastics performed in 40-50 min sessions, three times weekly for 12 weeks is recommended.

Sex-Specific Cut-Offs of Single Point Insulin Sensitivity Estimator (SPISE) in Predicting Metabolic Syndrome in the Arab Adolescents

The Single Point Insulin Sensitivity Estimator (SPISE) is a novel surrogate marker for insulin sensitivity and was found comparable to the gold standard clamp test as well as for predicting the Metabolic Syndrome (MetS) in several populations. The present study aimed to assess for the first time, the validity of SPISE in predicting MetS among Arab adolescents. In this cross-sectional study, 951 Saudi adolescents aged 10−17 years were randomly recruited from different schools across Riyadh, Saudi Arabia. Anthropometrics were measured and fasting blood samples were collected for the assessment of glucose, lipid profile, adipokines, C-reactive protein and 25 hydroxyvitamin (OH) D. MetS was defined using the National Cholesterol Education Program’s (NCEP) criteria with age-specific thresholds for adolescents. The SPISE as well as insulin resistance (HOMA-IR) indices were calculated. The over-all prevalence of MetS was 8.6% (82 out of 951). SPISE index was significantly lower in MetS than non-MetS participants in both sexes (5.5 ± 2.5 vs. 9.4 ± 3.2, p < 0.001 in boys and 4.4 ± 1.4 vs. 8.6 ± 3.2, p < 0.001 in girls). The SPISE index showed a significant inverse correlation with resistin, leptin, and C-reactive protein, and a significant positive correlation with adiponectin and 25(OH) D. Areas under the curve (AUC) revealed fair and good accuracy for predicting MetS 84.1% and 90.3% in boys and girls, respectively. The sex-specific cut-off proposed was SPISE index ≤6.1 (sensitivity 72.2% and specificity 83.9%) for boys and ≤6.46 (sensitivity 96.3% and specificity 73.4%), for girls. This study suggests that the SPISE index is a simple and promising diagnostic marker of insulin sensitivity and MetS in Arab adolescents.

Waist Circumference Is an Essential Factor in Predicting Insulin Resistance and Early Detection of Metabolic Syndrome in Adults

BACKGROUND

Metabolic syndrome (Met-S) is considered one of the most important health problems of the 21st century. It includes a group of metabolic disorders that increase the risk of cardiovascular diseases such as overweight and obesity, elevated lipid profile and blood pressure and insulin resistance (IR). Based on the information mentioned above in which there seems to be a relationship between IR and Met-S, the objective of this work was twofold: on the one hand, to assess the relationship between the values of different insulin resistance risk scales and Met-S determined with three different scales, and on the other, to determine whether any of the components of Met-S predispose more to the appearance of IR.

METHODS

A descriptive cross-sectional study of 418,343 workers. Waist circumference was measured and evaluated together with six formulas to assess the insulin resistance index. Categorical variables were evaluated by calculating the frequency and distribution of each one. For quantitative variables, mean and standard deviation were determined, and Student's t-test was applied, while for qualitative variables, the chi-square test was performed. The usefulness of the different risk scales for insulin resistance for predicting metabolic syndrome was evaluated using ROC curves, the area under the curve (AUC), as well as their cut-off points for sensitivity, specificity, and the Youden index.

RESULTS

People with metabolic syndrome applying any criteria had higher values in the IR risk scales. The different IR scales made it possible to adequately classify people with metabolic syndrome. Of the three definitions of Met-S, the one that showed the greatest relationship with IR was IDF.

CONCLUSIONS

Most risk scales for insulin resistance enable the presence of metabolic syndrome to be adequately classified, finding the best ones if the International Diabetes Federation (IDF) criteria are applied. Of the elements included in the Met-S, the one that seems to increase the risk of presenting IR the most is waist circumference; hence, the Met-S definition that is most related to IR is that of the IDF, which is the only one of the three in which a high value of waist circumference is necessary to be able to diagnose Met-S. Waist circumference can be considered the central essential component for detecting insulin resistance and, therefore, the early detection of metabolic syndrome.

Contributions of physical inactivity and sedentary behavior to metabolic and endocrine diseases

Physical inactivity is the fourth leading global cause of death and is a major contributor to metabolic and endocrine diseases. In this review we provide a current update of the past 5 years in the field as it pertains to the most prevalent and deadly chronic diseases. Despite the prevalence of physical inactivity in modern society, it remains largely overlooked relative to other comparable risk factors such as obesity, and our molecular understanding of how physical inactivity impacts metabolism is still partially unknown. Therefore, we discuss current clinical inactivity models along with their most recent findings regarding health outcomes along with any discrepancies that are present in the field. Lastly, we discuss future directions and the need for translatable animal models of physical inactivity to discover novel molecular targets for the prevention of chronic disease.

Inflammaging: Implications in Sarcopenia

In a world in which life expectancy is increasing, understanding and promoting healthy aging becomes a contemporary demand. In the elderly, a sterile, chronic and low-grade systemic inflammation known as "inflammaging" is linked with many age-associated diseases. Considering sarcopenia as a loss of strength and mass of skeletal muscle related to aging, correlations between these two terms have been proposed. Better knowledge of the immune system players in skeletal muscle would help to elucidate their implications in sarcopenia. Characterizing the activators of damage sensors and the downstream effectors explains the inference with skeletal muscle performance. Sarcopenia has also been linked to chronic diseases such as diabetes, metabolic syndrome and obesity. Implications of inflammatory signals from these diseases negatively affect skeletal muscle. Autophagic mechanisms are closely related with the inflammasome, as autophagy eliminates stress signaling sent by damage organelles, but also acts with an immunomodulatory function affecting immune cells and cytokine release. The use of melatonin, an antioxidant, ROS scavenger and immune and autophagy modulator, or senotherapeutic compounds targeting senescent cells could represent strategies to counteract inflammation. This review aims to present the many factors regulating skeletal muscle inflammaging and their major implications in order to understand the molecular mechanisms involved in sarcopenia.

Zishen Pill alleviates diabetes in Db/db mice via activation of PI3K/AKT pathway in the liver

Background

The rising global incidence of type 2 diabetes mellitus (T2DM) highlights a need for new therapies. The Zishen Pill (ZSP) is a traditional Chinese herbal decoction that has previously shown hypoglycemic effects in C57BL/KsJ-db/db mice, although the therapeutic mechanism remains unknown. This study aims to explore the underlying mechanisms of ZSP’s hypoglycemic effects using db/db mice.

Methods

Db/db mice were divided into two groups: model group and ZSP group, while wt/wt mice were used as a normal control. ZSP was given to mice by gavage for 40 days. During treatment, blood glucose level and body weight were monitored continuously. Oral glucose tolerance test (OGTT) was performed at day 35. Blood and tissue samples were collected at the end of treatment for further analyses. Mice liver samples were analyzed with mRNA transcriptomics using functional annotation and pathway enrichment to identify potential mechanisms that were then explored with qPCR and Western Blot techniques.

Results

ZSP treatment significantly reduced weight gain and glycemic severity in db/db mice. ZSP also partially restored the glucose homeostasis in db/db mice and increased the hepatic glycogen content. Transcriptomic analyses showed ZSP increased expression of genes involved in glycolysis including Hk2, Hk3, Gck and Pfkb1, and decreased expression of G6pase. Additionally, the gene and protein expression of phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway, and Csf1 and Flt3 mRNA expression were significantly upregulated in ZSP group.

Conclusion

ZSP treatment reduced the severity of diabetic symptoms in db/db mice. ZSP increased expression of genes associated with glycogen synthesis and glycolysis, and decreased gluconeogenesis via the enhancement of the PI3K/AKT signaling in the liver.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-022-00683-8.

TyGIS: improved triglyceride-glucose index for the assessment of insulin sensitivity during pregnancy

Background

The triglyceride-glucose index (TyG) has been proposed as a surrogate marker of insulin resistance, which is a typical trait of pregnancy. However, very few studies analyzed TyG performance as marker of insulin resistance in pregnancy, and they were limited to insulin resistance assessment at fasting rather than in dynamic conditions, i.e., during an oral glucose tolerance test (OGTT), which allows more reliable assessment of the actual insulin sensitivity impairment. Thus, first aim of the study was exploring in pregnancy the relationships between TyG and OGTT-derived insulin sensitivity. In addition, we developed a new version of TyG, for improved performance as marker of insulin resistance in pregnancy.

Methods

At early pregnancy, a cohort of 109 women underwent assessment of maternal biometry and blood tests at fasting, for measurements of several variables (visit 1). Subsequently (26 weeks of gestation) all visit 1 analyses were repeated (visit 2), and a subgroup of women (84 selected) received a 2 h-75 g OGTT (30, 60, 90, and 120 min sampling) with measurement of blood glucose, insulin and C-peptide for reliable assessment of insulin sensitivity (PREDIM index) and insulin secretion/beta-cell function. The dataset was randomly split into 70% training set and 30% test set, and by machine learning approach we identified the optimal model, with TyG included, showing the best relationship with PREDIM. For inclusion in the model, we considered only fasting variables, in agreement with TyG definition.

Results

The relationship of TyG with PREDIM was weak. Conversely, the improved TyG, called TyGIS, (linear function of TyG, body weight, lean body mass percentage and fasting insulin) resulted much strongly related to PREDIM, in both training and test sets (R² > 0.64, p < 0.0001). Bland–Altman analysis and equivalence test confirmed the good performance of TyGIS in terms of association with PREDIM. Different further analyses confirmed TyGIS superiority over TyG.

Conclusions

We developed an improved version of TyG, as new surrogate marker of insulin sensitivity in pregnancy (TyGIS). Similarly to TyG, TyGIS relies only on fasting variables, but its performances are remarkably improved than those of TyG.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01649-8.

Ten-year Time-trend Analysis of Dyslipidemia Among Adults in Wuhan

OBJECTIVE

Dyslipidemia is associated with an increased risk of cardiovascular disease, the major cause of death in an aging population. This study aimed to estimate the prevalence of dyslipidemia for the past decade among adults in Wuhan, China.

METHODS

We performed a serial cross-sectional study that recruited 705 219 adults from the Health Management Center of Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from 2010 to 2019. The diagnosis of dyslipidemia was based on the 2016 Chinese Guidelines for the Management of Dyslipidemia in Adults. Fixed effects and random effects models were applied to adjust the confounding variables (gender and age).

RESULTS

The overall prevalence of dyslipidemia was 33.1% (46.2% in men and 14.7% in women) in 2019. The prevalence of dyslipidemia was significantly increased over 10 years [from 28.6% (95% CI: 28.2%-29.1%) in 2010 to 32.8 % (95% CI:32.6%-33.1%) in 2019;. P-0.001], especially for hypo-high-density lipoprotein cholesterolemia [from 18.4% (95% CI: 18.0%-18.8%) in 2010 to 24.5% (95% CI: 24.3%-24.7%) in 2019; P-0.001]. In 2019, the prevalence of dyslipidemia was higher in participants with comorbidities, including overweight/obesity, hypertension, diabetes, hyperuricemia, or chronic kidney disease, and dyslipidemia was the most significant among participants aged 30-39 years.

CONCLUSION

This study demonstrated that dyslipidemia is on the rise in men, and more emphasis should be provided for the screening of dyslipidemia in young males for the primary prevention of cardiovascular and renal diseases.

Proposal for standardizing normal insulin ranges in Brazilian patients and a new classification of metabolic syndrome

Background

Insulin resistance and/or hyperinsulinemia are closely linked to adiposity, metabolic syndrome (MetS) and prolonged inflammatory processes.

Methods

We retrospectively analyzed 1,018 adult individuals with a mean age of 46 years (74% male) and classified them as: Metabolically normal: without any of the five criteria of the International Diabetes Federation (IDF) used for the diagnosis of MetS, plus normal fasting insulin (Men < 8 mU/L, Women < 10 mU/L); Level 1 MetS: with one or two IDF criteria, plus hyperinsulinemia (Men: ≥ 8 mU/L), and Women: ≥ 10 mU/L); Level 2 MetS: with three or more IDF criteria, plus hyperinsulinemia.

Results

The mean values for fasting insulinemia in metabolically normal individuals was 4.6 ± 1.8 mU/L and 5.6 ± 2.3 mU/L, while their means for the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) were 1.0 and 1.2 for men and women, respectively. In addition, the mean values for insulin (and HOMA-IR) for individuals with two normal anthropometric parameters (body mass index and waist girth), or two normal anthropometric parameters plus no IDF criteria, were similar to the metabolically normal group. Based on the obtained mean + 2 SD, we established the following insulin (and HOMA-IR) values as diagnostic cut-offs for hyperinsulinemia: Men: ≥ 8 mU/L (≥ 1.5), and Women: ≥ 10 mU/L (≥ 2.0). The mean serum insulin was significantly higher for individuals with Level 1 MetS (approx. 9 mU/L for both genders) compared with metabolically normal individuals, as was the prevalence of hepatic steatosis, which was more evident in men. Thus, the presence of one or two abnormal IDF criteria, combined with hyperinsulinemia and/or raised HOMA-IR, suggests the presence of MetS and insulin resistance. Patients of both genders with Level 2 MetS had higher serum insulin and/or HOMA-IR values than Level 1, as well as a higher prevalence of hypertension and hepatic steatosis, being more pronounced among men. The process was progressive and proportional to the degree of hyperinsulinemia.

Conclusion

It is proposed that intervention against MetS progression should be started in individuals with Level 1 MetS, rather than waiting for more criteria for diagnostic confirmation, which this should help to reduce the occurrence of known complications such as type 2 diabetes, atherosclerosis, hypertension, and chronic kidney disease, among others.

Depression in polycystic ovary syndrome: Focusing on pathogenesis and treatment

Polycystic ovary syndrome (PCOS) is one of the most prevalent gynecological endocrine conditions affecting reproductive women. It can feature a variety of symptoms, such as obesity, insulin resistance, skin conditions, and infertility. Women with PCOS are susceptible to illnesses including mood disorders, diabetes, hypertension, and dyslipidemia. Among them, depression is the most common in PCOS and has a detrimental effect on quality of life. Depression may occasionally develop due to the pathological traits of PCOS, but its exact pathogenesis in PCOS have eluded researchers to date. Therefore, there is an urgent need to explore the pathogenesis and treatments of depression in PCOS. The present review discusses the epidemiology of depression in PCOS, potential pathogenic mechanisms underlying PCOS and depression, as well as some potential factors causing depression in PCOS, including obesity, insulin resistance, hyperandrogenism, inflammation, and infertility. Meanwhile, some common treatment strategies for depression in PCOS, such as lifestyle intervention, acupuncture, oral contraceptive pills, psychological intervention, and insulin-sensitizer, are also reviewed. To fully understand the pathogenesis and treatment of depression in PCOS, a need remains for future large-scale multi-center randomized controlled trials and in-depth mechanism studies.

Associations of Serum Total 25OHD, 25OHD3, and epi-25OHD3 with Insulin Resistance: Cross-Sectional Analysis of the National Health and Nutrition Examination Survey, 2011–2016

Background: Vitamin D may have a role in insulin sensitivity. However, the data on the association between various metabolites of Vitamin D and insulin-related parameters have been limited. Methods: We identified 6026 adults aged 20–80 years who participated in the 2011–2016 National Health and Nutrition Examination Survey (NHANES). Serum total 25OHD, 25OHD3, and epi-25OHD3, fasting glucose, insulin, and HOMA2-IR were obtained from the NHANES data. The association between serum Vitamin D-related values and insulin resistance was analyzed using a generalized linear model. For risk analysis, multifactorial logistic regression was used. Results: The median total 25-hydroxyvitamin D level, 25-hydroxyvitamin D3 level, and 3-epi-25-hydroxyvitamin D3 level were 62.5 nmol/L, 58.8 nmol/L, and 3.3 nmol/L, respectively. After adjustment for sex, age, race, ethnicity, and education status, the ORs for the insulin resistance of participants of total 25-hydroxyvitamin D, 25-hydroxyvitamin D3, and 3-epi-25-hydroxyvitamin D3 were 0.32 (95% CI 0.24, 0.43), 0.34 (95% CI 0.26, 0.44), and 0.64 (95% CI 0.53, 0.77), respectively. After an adjustment for body mass index, diabetes, and drinking and smoking, the ORs for the insulin resistance of the participants for total 25-hydroxyvitamin D, 25-hydroxyvitamin D3, and 3-epi-25-hydroxyvitamin D3 were 0.56 (95% CI 0.40, 0.78), 0.63 (95% CI 0.46, 0.85), and 0.99 (95% CI 0.80, 1.24), respectively. Conclusions: Our study provides suggestive evidence for the association between Vitamin D concentrations and a lower risk of insulin resistance. Evidence from larger and more adequately powered cohort studies is needed to confirm our results.

Trends in insulin resistance: insights into mechanisms and therapeutic strategy

The centenary of insulin discovery represents an important opportunity to transform diabetes from a fatal diagnosis into a medically manageable chronic condition. Insulin is a key peptide hormone and mediates the systemic glucose metabolism in different tissues. Insulin resistance (IR) is a disordered biological response for insulin stimulation through the disruption of different molecular pathways in target tissues. Acquired conditions and genetic factors have been implicated in IR. Recent genetic and biochemical studies suggest that the dysregulated metabolic mediators released by adipose tissue including adipokines, cytokines, chemokines, excess lipids and toxic lipid metabolites promote IR in other tissues. IR is associated with several groups of abnormal syndromes that include obesity, diabetes, metabolic dysfunction-associated fatty liver disease (MAFLD), cardiovascular disease, polycystic ovary syndrome (PCOS), and other abnormalities. Although no medication is specifically approved to treat IR, we summarized the lifestyle changes and pharmacological medications that have been used as efficient intervention to improve insulin sensitivity. Ultimately, the systematic discussion of complex mechanism will help to identify potential new targets and treat the closely associated metabolic syndrome of IR.

The Roles of TNF Signaling Pathways in Metabolism of Bone Tumors

The metabolism of bone tumors is extraordinarily complex and involves many signaling pathways and processes, including the tumor necrosis factor (TNF) signaling pathway, which consists of TNF factors and the TNF receptors that belong to the TNF receptor superfamily (TNFRSF). It is appreciated that signaling events and pathways involving TNFRSF components are essential in coordinating the functions of multiple cell types that act as a host defense network against pathogens and malignant cells, the implications of TNFRSF-related signaling pathways on bone tumor metabolism remain to be summarized, which is one of the significant obstacles to the application of TNF-related treatment modalities in the domain of bone oncology. This review will discuss and summarize the anti-tumor properties of important TNFRSF components concerning osteosarcoma, chondrosarcoma, and Ewing sarcoma.

Equipment-free, unsupervised high intensity interval training elicits significant improvements in the physiological resilience of older adults

Background

Reduced cardiorespiratory fitness (CRF) is an independent risk factor for dependency, cognitive impairment and premature mortality. High-intensity interval training (HIIT) is a proven time-efficient stimulus for improving both CRF and other facets of cardiometabolic health also known to decline with advancing age. However, the efficacy of equipment-free, unsupervised HIIT to improve the physiological resilience of older adults is not known.

Methods

Thirty independent, community-dwelling older adults (71(SD: 5) years) were randomised to 4 weeks (12 sessions) equipment-free, supervised (in the laboratory (L-HIIT)) or unsupervised (at home (H-HIIT)) HIIT, or a no-intervention control (CON). HIIT involved 5, 1-minute intervals of a bodyweight exercise each interspersed with 90-seconds recovery. CRF, exercise tolerance, blood pressure (BP), body composition, muscle architecture, circulating lipids and glucose tolerance were assessed at baseline and after the intervention period.

Results

When compared to the control group, both HIIT protocols improved the primary outcome of CRF ((via anaerobic threshold) mean difference, L-HIIT: +2.27, H-HIIT: +2.29, both p < 0.01) in addition to exercise tolerance, systolic BP, total cholesterol, non-HDL cholesterol and m. vastus lateralis pennation angle, to the same extent. There was no improvement in these parameters in CON. There was no change in diastolic BP, glucose tolerance, whole-body composition or HDL cholesterol in any of the groups.

Conclusions

This is the first study to show that short-term, time-efficient, equipment-free, HIIT is able to elicit improvements in the CRF of older adults irrespective of supervision status. Unsupervised HIIT may offer a novel approach to improve the physiological resilience of older adults, combating age-associated physiological decline, the rise of inactivity and the additional challenges currently posed by the COVID-19 pandemic.

Trial registration

This study was registered at clinicaltrials.gov and coded: NCT03473990.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03208-y.

Dietary Magnesium Intake Level Modifies the Association Between Vitamin D and Insulin Resistance: A Large Cross-Sectional Analysis of American Adults

Background

Previous clinical studies and randomized controlled trials have revealed that low serum vitamin D levels are associated with the risk of developing insulin resistance. Magnesium has been reported to be a protective factor for insulin resistance, and magnesium has been considered an important co-factor for vitamin D activation. However, the effect of dietary magnesium intake on the relationship between vitamin D and the risk of developing insulin resistance has not been comprehensively investigated. Therefore, we designed this cross-sectional analysis to assess whether dietary magnesium intake modifies the association of vitamin D and insulin resistance.

Methods

A total of 4,878 participants (male: 48.2%) from 4 consecutive cycles of the National Health and Nutrition Examination Survey (2007-2014) were included in this study after a rigorous screening process. Participants were stratified by their dietary magnesium intake into low-intake (<267 mg/day) and high-intake (≥267 mg/day) groups. We assessed differences between serum vitamin D levels and the risk of developing insulin resistance (interaction test), using a weighted multivariate logistic regression to analyze differences between participants with low and high magnesium intake levels.

Results

There was a negative association between vitamin D and insulin resistance in the US adult population [OR: 0.93 (0.88-0.98)], P < 0.001. Dietary magnesium intake strengthened the association (P for interaction < 0.001). In the low dietary magnesium intake group, vitamin D was negatively associated with the insulin resistance [OR: 0.94 (0.90-0.98)]; in the high dietary magnesium intake group, vitamin D was negatively associated with insulin resistance [OR: 0.92 (0.88-0.96)].

Conclusion

Among adults in the United States, we found an independent association between vitamin D level and insulin resistance, and this association was modified according to different levels of magnesium intake.

Effect of vitamin D levels on the hormonal and metabolic status in patients with metabolic syndrome and chronic kidney disease

Aim. To assess the association of vitamin D deficiency with hormonal and metabolic disorders, including with insulin resistance and leptin levels, in patients with metabolic syndrome (MS) and chronic kidney disease (CKD).

Material and methods. The study included 81 patients with MS and CKD aged 45-59 years (mean age, 51±4 years). Depending on vitamin D level, the patients were divided into two groups: group 1 (n=49) — patients with reduced level (23,2±5,1 ng/ml); group 2 (n=32) — patients with an adequate level (54,8±12,1 ng/ml). Statistical processing was carried out using STATISTICA 10.0 software.

Results. In patients of the first group, the following parameters were higher than in the second one: waist circumference by 9,0% (p<0,05), waist-to-hip ratio by 8,2% (p<0,05), body mass index by 15,1% (p<0,05). The groups did not differ significantly in systolic and diastolic blood pressure levels. In the first group, the level of total cholesterol by 18,6% (p<0,01), low density lipoprotein cholesterol by 11,9% (p<0,05), triglycerides by 20,8% (p<0,01), Homeostasis Model Assessment Insulin Resistance (HOMA-IR) by 42,5% (p<0,001), leptin by 30,5% (p<0,01) were higher than in the second group. More severe left ventricular diastolic dysfunction in the first group than in the second one was determined as follows: lower left ventricular early to late filling (E/A) by 13,2% (p<0,05) and deceleration time of the early transmitral flow velocity by 13,1% (p<0,05).

Conclusion. The results obtained indicate that patients with MS, CKD and vitamin D deficiency are more likely to have general obesity, more pronounced carbohydrate (HOMA-IR index) and fat (levels of total cholesterol, low-density lipoprotein cholesterol, triglycerides) metabolism disorders, as well as high serum levels of leptin compared with patients with adequate levels of this vitamin.

Efficacy of a Novel Therapeutic, Based on Natural Ingredients and Probiotics, in a Murine Model of Multiple Food Intolerance and Maldigestion

Patients with hypersensitive gut mucosa often suffer from food intolerances (FIs) associated with an inadequate gastrointestinal function that affects 15-20% of the population. Current treatments involve elimination diets, but require careful control, are difficult to maintain long-term, and diagnosis remains challenging. This study aims to evaluate the beneficial effects of a novel therapeutic of natural (NTN) origin containing food-grade polysaccharides, proteins, and grape seed extract to restore intestinal function in a murine model of fructose, carbohydrate, and fat intolerances. All experiments were conducted in four-week-old male CD1 mice. To induce FIs, mice were fed with either a high-carbohydrate diet (HCD), high-fat diet (HFD), or high-fructose diet (HFrD), respectively. After two weeks of treatment, several parameters and endpoints were evaluated such as food and water intake, body weight, histological score in several organs, gut permeability, intestinal epithelial integrity, and biochemical endpoints. Our results demonstrated that the therapeutic agent significantly restored gut barrier integrity and permeability compromised by every FIs induction. Restoration of intestinal function by NTN treatment has consequently improved tissue damage in several functional organs involved in the diagnostic of each intolerance such as the pancreas for HCD and liver for HFD and HFrD. Taken together, our results support NTN as a promising natural option in the non-pharmacological strategy for the recovery of intestinal dysregulation, supporting the well-being of the gastrointestinal tract.

Systematic analysis of nutrigenomic effects of polyphenols related to cardiometabolic health in humans - Evidence from untargeted mRNA and miRNA studies

Cardiovascular and metabolic disorders present major causes of mortality in the ageing population. Polyphenols present in human diets possess cardiometabolic protective properties, however their underlying molecular mechanisms in humans are still not well identified. Even though preclinical and in vitro studies advocate that these bioactives can modulate gene expression, most studies were performed using targeted approaches. With the objective to decipher the molecular mechanisms underlying polyphenols cardiometabolic preventive properties in humans, we performed integrative multi-omic bioinformatic analyses of published studies which reported improvements of cardiometabolic risk factors following polyphenol intake, together with genomic analyses performed using untargeted approach. We identified 5 studies within our criteria and nearly 5000 differentially expressed genes, both mRNAs and miRNAs, in peripheral blood cells. Integrative bioinformatic analyses (e.g. pathway and gene network analyses, identification of transcription factors, correlation of gene expression profiles with those associated with diseases and drug intake) revealed that these genes are involved in the processes such as cell adhesion and mobility, immune system, metabolism, or cell signaling. We also identified 27 miRNAs known to regulate processes such as cell cytoskeleton, chemotaxis, cell signaling, or cell metabolism. Gene expression profiles negatively correlated with expression profiles of cardiovascular disease patients, while a positive correlation was observed with gene expression profiles following intake of drugs against cardiometabolic disorders. These analyses further advocate for health protective effects of these bioactives against age-associated diseases. In conclusion, polyphenols can exert multi-genomic modifications in humans and use of untargeted methods coupled with bioinformatic analyses represent the best approach to decipher molecular mechanisms underlying healthy-ageing effects of these bioactives.

Dietary and lifestyle indices for hyperinsulinemia with the risk of obesity phenotypes: a prospective cohort study among Iranian adult population

BACKGROUND

Previous studies have cited insulin-related disorders, including hyperinsulinemia, as one of the main causes of obesity risk and metabolic disorders. We aimed to investigate the association of the Empirical Dietary Index for Hyperinsulinemia (EDIH) and Empirical Lifestyle Index for Hyperinsulinemia (ELIH) with the risk of obesity phenotypes among Iranian adults.

METHODS

Present study was conducted on 2705 subjects, including 1604 metabolically healthy normal weights (MHNW) and 1101 metabolically healthy obesity (MHO) individuals. Obesity phenotypes, including MHNW, MHO, metabolically unhealthy normal weights (MUNW), and metabolic unhealthy obesity (MUO), were determined using the criteria of the Joint International statement (JIS) for metabolic syndrome. Dietary intake data from the previous year was gathered using a food frequency questionnaire. Cox proportional hazard regression was used to estimate the hazard ratio and 95% confidence intervals (HRs and 95% CIs) of obesity phenotypes incident across tertiles of EDIH and ELIH scores.

RESULTS

The mean ± SD of age and BMI of all participants were 33.5 ± 12.2 years and 24.3 ± 3.8 kg/m2, respectively. In the multivariable-adjusted model, a higher ELIH score was associated with a greater risk for incidence of MUO (HR: 3.47, 95%CI: 2.54-4.74; Ptrend =  < 0.001) and MHO (HR: 3.61, 95%CI: 2.73-4.77; Ptrend =  < 0.001). Also, a higher score of EDIH was related to an increased risk of MUO incidence (HR: 1.35, 95%CI: 1.02-1.79; P for trend = 0.046). However, there was no significant association between a higher score of EDIH and the risk of MHO.

CONCLUSION

Our findings revealed that a high insulinemic potential of diet and lifestyle, determined by EDIH and ELIH indices, may be related to an increase in the simultaneous occurrence of obesity with metabolic disorders in Iranian adults.

TLR4 mutation protects neurovascular function and cognitive decline in high-fat diet-fed mice

Background

Metabolic syndrome (MS) is defined as a low-grade proinflammatory state in which abnormal metabolic and cardiovascular factors increase the risk of developing cardiovascular disease and neuroinflammation. Events, such as the accumulation of visceral adipose tissue, increased plasma concentrations of free fatty acids, tissue hypoxia, and sympathetic hyperactivity in MS may contribute to the direct or indirect activation of Toll-like receptors (TLRs), specifically TLR4, which is thought to be a major component of this syndrome. Activation of the innate immune response via TLR4 may contribute to this state of chronic inflammation and may be related to the neuroinflammation and neurodegeneration observed in MS. In this study, we investigated the role of TLR4 in the brain microcirculation and in the cognitive performance of high-fat diet (HFD)-induced MS mice.

Methods

Wild-type (C3H/He) and TLR4 mutant (C3H/HeJ) mice were maintained under a normal diet (ND) or a HFD for 24 weeks. Intravital video-microscopy was used to investigate the functional capillary density, endothelial function, and endothelial–leukocyte interactions in the brain microcirculation. Plasma concentrations of monocyte chemoattractant protein-1 (MCP-1), adipokines and metabolic hormones were measured with a multiplex immunoassay. Brain postsynaptic density protein-95 and synaptophysin were evaluated by western blotting; astrocytic coverage of the vessels, microglial activation and structural capillary density were evaluated by immunohistochemistry.

Results

The HFD-induced MS model leads to metabolic, hemodynamic, and microcirculatory alterations, as evidenced by capillary rarefaction, increased rolling and leukocyte adhesion in postcapillary venules, endothelial dysfunction, and less coverage of astrocytes in the vessels, which are directly related to cognitive decline and neuroinflammation. The same model of MS reproduced in mice deficient for TLR4 because of a genetic mutation does not generate such changes. Furthermore, the comparison of wild-type mice fed a HFD and a normolipid diet revealed differences in inflammation in the cerebral microcirculation, possibly related to lower TLR4 activation.

Conclusions

Our results demonstrate that TLR4 is involved in the microvascular dysfunction and neuroinflammation associated with HFD-induced MS and possibly has a causal role in the development of cognitive decline.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-022-02465-3.

Acacetin Protects against Non-Alcoholic Fatty Liver Disease by Regulating Lipid Accumulation and Inflammation in Mice

We previously demonstrated that acacetin reduces adipogenesis in adipocytes, and decreases lipid accumulation in visceral adipocyte tissue. Here we investigated whether acacetin regulated the mechanisms of lipogenesis and inflammation in non-alcoholic fatty liver disease (NAFLD) in obese mice. Male C57BL/6 mice were fed a high-fat diet (HFD), and then administered acacetin by intraperitoneal injection. Acacetin reduced body weight and liver weight in obese mice. Acacetin-treated obese mice exhibited decreased lipid accumulation, increased glycogen accumulation, and improved hepatocyte steatosis. Acacetin regulated triglycerides and total cholesterol in the liver and serum. Acacetin decreased low-density lipoprotein and leptin concentrations, but increased high-density lipoprotein and adiponectin levels in obese mice. Acacetin effectively weakened the gene expressions of transcription factors related to lipogenesis, and promoted the expressions of genes related to lipolysis and fatty acid β-oxidation in liver. Acacetin also reduced expressions of inflammation-related cytokines in the serum and liver. Oleic acid induced lipid accumulation in murine FL83B hepatocytes, and the effects of acacetin treatment indicated that acacetin may regulate lipid metabolism through the AMPK pathway. Acacetin may protect against hepatic steatosis by modulating inflammation and AMPK expression.

Nuts and Metabolic Syndrome: Reducing the Burden of Metabolic Syndrome in Menopause

Menopause imposes a dramatic fall in estrogens, which is followed by an increase in the proportion of fat. The rising androgen/estrogen ratio along the menopause transition favors the accumulation of central fat, which contributes to insulin resistance and a series of concatenated effects, leading to a higher incidence of metabolic syndrome. The modulatory effect of diet on the metabolic syndrome phenotype has been shown for the Mediterranean diet, and nuts are key determinants of these health benefits. This review of the impact of nuts on the risk factors of the metabolic syndrome cluster examined studies—prioritizing meta-analyses and systemic reviews—to summarize the potential benefits of nut ingestion on the risk of metabolic syndrome associated with menopause. Nuts have a general composition profile that includes macronutrients, with a high proportion of unsaturated fat, bioactive compounds, and fiber. The mechanisms set in motion by nuts have shown different levels of efficacy against the disturbances associated with metabolic syndrome, but a beneficial impact on lipids and carbohydrate metabolism, and a potential, but minimal reduction in blood pressure and fat accumulation have been found.

Pathophysiological Link between Insulin Resistance and Adrenal Incidentalomas

Adrenal incidentalomas are incidentally discovered adrenal masses greater than one centimeter in diameter. An association between insulin resistance and adrenal incidentalomas has been established. However, the pathophysiological link between these two conditions remains incompletely characterized. This review examines the literature on the interrelationship between insulin resistance and adrenal masses, their subtypes, and related pathophysiology. Some studies show that functional and non-functional adrenal masses elicit systemic insulin resistance, whereas others conclude the inverse. Insulin resistance, hyperinsulinemia, and the anabolic effects on adrenal gland tissue, which have insulin and insulin-like growth factor-1 receptors, offer possible pathophysiological links. Conversely, autonomous adrenal cortisol secretion generates visceral fat accumulation and insulin resistance. Further investigation into the mechanisms and timing of these two pathologies as they relate to one another is needed and could be valuable in the prevention, detection, and treatment of both conditions.

α-Lipoic Acid Reduces Ceramide Synthesis and Neuroinflammation in the Hypothalamus of Insulin-Resistant Rats, While in the Cerebral Cortex Diminishes the β-Amyloid Accumulation

Background

Oxidative stress underlies metabolic diseases and cognitive impairment; thus, the use of antioxidants may improve brain function in insulin-resistant conditions. We are the first to evaluate the effects of α-lipoic acid (ALA) on redox homeostasis, sphingolipid metabolism, neuroinflammation, apoptosis, and β-amyloid accumulation in the cerebral cortex and hypothalamus of insulin-resistant rats.

Methods

The experiment was conducted on male cmdb/outbred Wistar rats fed a high-fat diet (HFD) for 10 weeks with intragastric administration of ALA (30 mg/kg body weight) for 4 weeks. Pro-oxidant and pro-inflammatory enzymes, oxidative stress, sphingolipid metabolism, neuroinflammation, apoptosis, and β-amyloid level were assessed in the hypothalamus and cerebral cortex using colorimetric, fluorimetric, ELISA, and HPLC methods. Statistical analysis was performed using three-way ANOVA followed by the Tukey HSD test.

Results

ALA normalizes body weight, food intake, glycemia, insulinemia, and systemic insulin sensitivity in HFD-fed rats. ALA treatment reduces nicotinamide adenine dinucleotide phosphate (NADPH) and xanthine oxidase activity, increases ferric-reducing antioxidant power (FRAP) and thiol levels in the hypothalamus of insulin-resistant rats. In addition, it decreases myeloperoxidase, glucuronidase, and metalloproteinase-2 activity and pro-inflammatory cytokines (IL-1β, IL-6) levels, while in the cerebral cortex ALA reduces β-amyloid accumulation. In both brain structures, ALA diminishes ceramide synthesis and caspase-3 activity. ALA improves systemic oxidative status and reduces insulin-resistant rats’ serum cytokines, chemokines, and growth factors.

Conclusion

ALA normalizes lipid and carbohydrate metabolism in insulin-resistant rats. At the brain level, ALA primarily affects hypothalamic metabolism. ALA improves redox homeostasis by decreasing the activity of pro-oxidant enzymes, enhancing total antioxidant potential, and reducing protein and lipid oxidative damage in the hypothalamus of HFD-fed rats. ALA also reduces hypothalamic inflammation and metalloproteinases activity, and cortical β-amyloid accumulation. In both brain structures, ALA diminishes ceramide synthesis and neuronal apoptosis. Although further study is needed, ALA may be a potential treatment for patients with cerebral complications of insulin resistance.