Metabolic syndrome and insulin resistance: underlying causes and modification by exercise training

Identification of genetic variants for blood insulin level in sex-stratified Korean population and evaluation of the causal relationship between blood insulin level and polycystic ovary syndrome

BACKGROUND

Blood insulin level is an important risk factor for numerous disorders. Individual blood insulin level is known to be substantially influenced by genetic factors. Several genetic association studies identified a number of genetic variants for blood insulin level, but none of them was from a sex-stratified population.

OBJECTIVE

This study aimed to identify male- and female-specific genetic variants related to blood insulin level and to evaluate the causal relationship between blood insulin level and polycystic ovary syndrome (PCOS) that is likely caused by high insulin in Korean women.

METHODS

A genome-wide association study was conducted to identify genetic variants influencing blood insulin level in males (N = 4183) and females (N = 4659) in the Korean population. Two-sample Mendelian randomization (MR) analysis was used to investigate the causal effects of the insulin variants identified from GWAS on PCOS in Korean women. Genetic association data for PCOS were obtained from a PCOS study cohort (946 cases, 976 controls) in Ewha Womans University Hospital.

RESULTS

GWAS linear regression analysis identified 13 female-specific SNPs and 13 male-specific SNPs showing suggestive associations (P < 10^-5) with blood insulin level. The results from two-sample MR analysis using the GWAS variants for PCOS indicated that genetically determined insulin level was not associated with the risk of PCOS in Korean women.

CONCLUSION

This study identified sex-specific genetic variants showing associations with insulin for the first time in East Asian populations. In addition, MR analysis using variants discovered from Korean women revealed that genetically determined high level of insulin is not the cause of PCOS.

Metformin Affects Cardiac Arachidonic Acid Metabolism and Cardiac Lipid Metabolite Storage in a Prediabetic Rat Model

Metformin can reduce cardiovascular risk independent of glycemic control. The mechanisms behind its non-glycemic benefits, which include decreased energy intake, lower blood pressure and improved lipid and fatty acid metabolism, are not fully understood. In our study, metformin treatment reduced myocardial accumulation of neutral lipids—triglycerides, cholesteryl esters and the lipotoxic intermediates—diacylglycerols and lysophosphatidylcholines in a prediabetic rat model (p < 0.001). We observed an association between decreased gene expression and SCD-1 activity (p < 0.05). In addition, metformin markedly improved phospholipid fatty acid composition in the myocardium, represented by decreased SFA profiles and increased n3-PUFA profiles. Known for its cardioprotective and anti-inflammatory properties, metformin also had positive effects on arachidonic acid metabolism and CYP-derived arachidonic acid metabolites. We also found an association between increased gene expression of the cardiac isoform CYP2c with increased 14,15-EET (p < 0.05) and markedly reduced 20-HETE (p < 0.001) in the myocardium. Based on these results, we conclude that metformin treatment reduces the lipogenic enzyme SCD-1 and the accumulation of the lipotoxic intermediates diacylglycerols and lysophosphatidylcholine. Increased CYP2c gene expression and beneficial effects on CYP-derived arachidonic acid metabolites in the myocardium can also be involved in cardioprotective effect of metformin.

Relationship between anti-insulin antibody production and severe insulin resistance in a diabetic cat

A 5-year-old castrated male domestic shorthair cat was diagnosed with diabetic ketoacidosis and severe insulin resistance. Although the conventional treatment for diabetic ketoacidosis was provided, the cat required frequent hospitalization because of severe dehydration and repeated diabetic ketoacidosis. We detected anti-insulin antibodies for human in this cat. Serum insulin-binding IgG levels were markedly elevated compared with those in healthy cats and other diabetic cats. We initiated prednisolone to suppress the effects of anti-insulin antibodies. After initiation of prednisolone, the cat was gradually recovered with increasing activity and appetite. Furthermore, satisfactory glycemic control was achieved with combined subcutaneous injection of insulin detemir and insulin degludec.

Association between Physical Activity and Seasonal Variations in Metabolic and Vascular Function in Adults

This article highlights the association between physical activity (PA) and seasonal variations in metabolic and vascular function in adults. Increasing PA is an important method for preventing cardiovascular disease (CVD) and all-cause mortality by improving blood glucose, blood pressure, blood lipid profiles, body fat, insulin resistance, and vascular function, such as endothelial function. Conversely, various factors, such as seasonal climate conditions, may affect the amount of PA that individuals undertake. Changes in PA often induce seasonal variations in metabolic and vascular function; the deterioration of such functions in winter is the most prominent, and there is clear evidence of an increased risk of CVD in this season. Understanding the influence of PA on seasonal variations observed in metabolic and vascular function is necessary for the management of these physiological functions. In this article summary, few studies have proven that maintaining PA can suppress the variations, and it remains unclear what types, intensities, and durations of regular PA are effective for circumventing seasonal impact. In addition to further studies, there is a need to educate individuals about the strategies to manage PA and other aspects of their lifestyles throughout the year, particularly in winter.

Differential insulin sensitivity of NMR-based metabolomic measures in a two-step hyperinsulinemic euglycemic clamp study

BACKGROUND

Insulin is the key regulator of glucose metabolism, but it is difficult to dissect direct insulin from glucose-induced effects. We aimed to investigate the effects of hyperinsulemia on metabolomic measures under euglycemic conditions in nondiabetic participants.

METHODS

We assessed concentrations of 151 metabolomic measures throughout a two-step hyperinsulinemic euglycemic clamp procedure. We included 24 participants (50% women, mean age = 62 [s.d. = 4.2] years) and metabolomic measures were assessed under baseline, low-dose (10 mU/m²/min) and high-dose (40 mU/m²/min) insulin conditions. The effects of low- and high-dose insulin infusion on metabolomic measures were analyzed using linear mixed-effect models for repeated measures.

RESULTS

After low-dose insulin infusion, 90 metabolomic measures changed in concentration (p < 1.34e^-4), among which glycerol (beta [Confidence Interval] =  - 1.41 [- 1.54, - 1.27] s.d., p = 1.28e^-95) and three-hydroxybutyrate (- 1.22 [- 1.36, - 1.07] s.d., p = 1.44e^-61) showed largest effect sizes. After high-dose insulin infusion, 121 metabolomic measures changed in concentration, among which branched-chain amino acids showed the largest additional decrease compared with low-dose insulin infusion (e.g., Leucine, - 1.78 [- 1.88, - 1.69] s.d., P = 2.7e^-295). More specifically, after low- and high-dose insulin infusion, the distribution of the lipoproteins shifted towards more LDL-sized particles with decreased mean diameters.

CONCLUSION

Metabolomic measures are differentially insulin sensitive and may thus be differentially affected by the development of insulin resistance. Moreover, our data suggests insulin directly affects metabolomic measures previously associated with increased cardiovascular disease risk.

Natural Polyphenols in Metabolic Syndrome: Protective Mechanisms and Clinical Applications

Metabolic syndrome (MetS) is a chronic disease, including abdominal obesity, dyslipidemia, hyperglycemia, and hypertension. It should be noted that the occurrence of MetS is closely related to oxidative stress-induced mitochondrial dysfunction, ectopic fat accumulation, and the impairment of the antioxidant system, which in turn further aggravates the intracellular oxidative imbalance and inflammatory response. As enriched anti-inflammatory and antioxidant components in plants, natural polyphenols exhibit beneficial effects, including improving liver fat accumulation and dyslipidemia, reducing blood pressure. Hence, they are expected to be useful in the prevention and management of MetS. At present, epidemiological studies indicate a negative correlation between polyphenol intake and MetS incidence. In this review, we summarized and discussed the most promising natural polyphenols (including flavonoid and non-flavonoid drugs) in the precaution and treatment of MetS, including their anti-inflammatory and antioxidant properties, as well as their regulatory functions involved in glycolipid homeostasis.

Metformin Improves Autonomic Nervous System Imbalance and Metabolic Dysfunction in Monosodium L-Glutamate-Treated Rats

Metformin is an antidiabetic drug used for the treatment of diabetes and metabolic diseases. Imbalance in the autonomic nervous system (ANS) is associated with metabolic diseases. This study aimed to test whether metformin could improve ANS function in obese rats. Obesity was induced by neonatal treatment with monosodium L-glutamate (MSG). During 21-100 days of age, MSG-rats were treated with metformin 250 mg/kg body weight/day or saline solution. Rats were euthanized to evaluate biometric and biochemical parameters. ANS electrical activity was recorded and analyzed. Metformin normalized the hypervagal response in MSG-rats. Glucose-stimulated insulin secretion in isolated pancreatic islets increased in MSG-rats, while the cholinergic response decreased. Metformin treatment normalized the cholinergic response, which involved mostly the M3 muscarinic acetylcholine receptor (M3 mAChR) in pancreatic beta-cells. Protein expression of M3 mAChRs increased in MSG-obesity rats, while metformin treatment decreased the protein expression by 25%. In conclusion, chronic metformin treatment was effective in normalizing ANS activity and alleviating obesity in MSG-rats.

Association of Carbohydrate and Fat Intake with Prevalence of Metabolic Syndrome Can Be Modified by Physical Activity and Physical Environment in Ecuadorian Adults: The ENSANUT-ECU Study

The associations of lifestyle and environment with metabolic syndrome (MetS) and cardiovascular disease have recently resulted in increased attention in research. This study aimed to examine interactive associations among carbohydrate and fat intake, physical environment (i.e., elevation and humidity), lifestyle, and MetS among Ecuadorian adults. We used data from the Ecuador National Health and Nutrition Survey 2012 (ENSANUT-ECU), with a total of 6023 participants aged 20 to 60 years included in this study. Logistic regression was used to determine the association of status of carbohydrate and fat intake, low-carbohydrate high-fat diet (LCHF) and medium-carbohydrate and fat (MCF) diet with MetS, where the high-carbohydrate low-fat (HCLF) diet was used as a reference. Women with LCHF and MCF diets showed lower prevalence of increased blood pressure (OR = 0.34, 95% CI: 0.19–0.59; OR = 0.50, 95% CI: 0.32–0.79, respectively). Women with MCF diet also showed lower prevalence of elevated fasting glucose (OR = 0.58, 95% CI: 0.37–0.91). Moreover, there were negative associations between MetS and reduced HDL cholesterol in women with MCF diet residing in low relative humidity (OR = 0.66, 95% CI: 0.45–0.98) and in women with LCHF diet residing at a high elevation (OR = 0.37, 95% CI: 0.16–0.86). Additionally, higher prevalence of increased waist circumference was observed in men with both MFC and LCHF diets who were physically inactive (OR = 1.89, 95% CI: 1.12–3.20; OR = 2.34, 95% CI: 1.19–4.60, respectively) and residing in high relative humidity (OR = 1.90, 95% CI: 1.08–2.89; OR = 2.63, 95% CI: 1.32–5.28, respectively). Our findings suggest that LCHF intake is associated with lower blood pressure, while MCF intake is associated with lower blood pressure and fasting glucose in Ecuadorian women. Furthermore, the associations of carbohydrate and fat intake with prevalence of MetS can be modified by physical activity, relative humidity, and elevation. The obtained outcomes may provide useful information for health programs focusing on dietary intake and lifestyle according to physical environment of the population to promote health and prevent metabolic diseases.

Associations Between Single-Child Status and Metabolic Syndrome in Children and Adolescents in China

Objective: To evaluate the associations between single-child status and metabolic syndrome (MS) and to identify the highest risk group of MS among single children. Methods: Differences in participants' characteristics by sex were examined by Student's t-test for continuous variables and Pearson's chi-squared test for categorical variables. Multivariate logistic regression analysis was performed to estimate the odds ratios (OR) and 95% confidence intervals (CI) for MS and its components according to the single-child status. Radar maps were used to compare the composition of different components in MS. Results: In total, 11,784 (5,880 boys) children and adolescents were included in this study, with a mean age of (11.3 ± 3.1) years. MS was observed in 7.1% of participants, with a higher prevalence in boys (8.2%) than girls (5.9%) (P < 0.05). The prevalence of MS, elevated blood pressure and abdominal obesity in single children were higher than that in children with siblings, particularly in boys (P < 0.001). Elevated risk of abdominal obesity was observed in single children [boys (1.56, 95% CI: 1.31, 1.85), girls (1.40, 95% CI: 1.19, 1.63)], however, increased ORs of elevated blood pressure and metabolic syndrome were observed in single-child boys only (1.19, 95% CI: 1.01, 1.40 and 1.76, 95% CI: 1.34, 2.31, respectively). Results showed that a statistically significant association between single child status and MS was mainly observed in urban boys (2.04, 95% CI: 1.33, 3.12) and rural boys (1.50, 95% CI: 1.05, 2.15), but not in girls. Among all the combinations of MS, two combinations were significantly associated with the single-child status, including the combination of elevated blood pressure, abdominal and low HDL-C (1.45, 1.04, 2.04) and the combination of elevated blood pressure, abdominal obesity, low HDL-C and hypertriglyceridemia (2.04, 1.40, 3.06) (P < 0.05). Conclusions: The present study found that single children and adolescents had a higher risk of MS, elevated blood pressure and abdominal obesity. The associations were stronger in urban boys. Further attention should be directed to the prevention and control strategies targeting the high-risk population of MS.

Physical Activity and Cumulative Long-Term Care Cost among Older Japanese Adults: A Prospective Study in JAGES

This study aimed to determine the impact of physical activity on the cumulative cost of long-term care insurance (LTCI) services in a cohort of community-dwelling people (65 years and older) in Japan. Using cohort data from the Japan Gerontological Evaluation Study (JAGES) on those who were functionally independent as of 2010/11, we examined differences in the cumulative cost of LTCI services by physical activity. We followed 38,875 participants with LTCI service costs for 59 months. Physical activity was assessed by the frequency of going out and time spent walking. We adopted a generalized linear model with gamma distribution and log-link function, and a classical linear regression with multiple imputation. The cumulative LTCI costs significantly decreased with the frequency of going out and the time spent walking after adjustment for baseline covariates. LTCI's cumulative cost for those who went out once a week or less was USD 600 higher than those who went out almost daily. Furthermore, costs for those who walked for less than 30 min were USD 900 higher than those who walked for more than 60 min. Physical activity among older individuals can reduce LTCI costs, which could provide a rationale for expenditure intervention programs that promote physical activity.

Metforminium Decavanadate (MetfDeca) Treatment Ameliorates Hippocampal Neurodegeneration and Recognition Memory in a Metabolic Syndrome Model

The consumption of foods rich in carbohydrates, saturated fat, and sodium, accompanied by a sedentary routine, are factors that contribute to the progress of metabolic syndrome (MS). In this way, they cause the accumulation of body fat, hypertension, dyslipidemia, and hyperglycemia. Additionally, MS has been shown to cause oxidative stress, inflammation, and death of neurons in the hippocampus. Consequently, spatial and recognition memory is affected. It has recently been proposed that metformin decavanadate (MetfDeca) exerts insulin mimetic effects that enhance metabolism in MS animals; however, what effects it can cause on the hippocampal neurons of rats with MS are unknown. The objective of the work was to evaluate the effect of MetfDeca on hippocampal neurodegeneration and recognition memory in rats with MS. Administration of MetfDeca for 60 days in MS rats improved object recognition memory (NORt). In addition, MetfDeca reduced markers of oxidative stress and hippocampal neuroinflammation. Accompanied by an increase in the density and length of the dendritic spines of the hippocampus of rats with MS. We conclude that MetfDeca represents an important therapeutic agent to treat MS and induce neuronal and cognitive restoration mechanisms.

The impacts of exercise on pediatric obesity

Over the last few decades, the rates of pediatric obesity have more than doubled regardless of sociodemographic categorization, and despite these rates plateauing in recent years there continues to be an increase in the severity of obesity in children and adolescents. This review will discuss the pediatric obesity mediated cardiovascular disease (CVD) risk factors such as attenuated levels of satiety and energy metabolism hormones, insulin resistance, vascular endothelial dysfunction, and arterial stiffness. Additionally, early intervention to combat pediatric obesity is critical as obesity has been suggested to track into adulthood, and these obese children and adolescents are at an increased risk of early mortality. Current suggested strategies to combat pediatric obesity are modifying diet, limiting sedentary behavior, and increasing physical activity. The effects of exercise intervention on metabolic hormones such as leptin and adiponectin, insulin sensitivity/resistance, and body fat in obese children and adolescents will be discussed along with the exercise modality, intensity, and duration. Specifically, this review will focus on the differential effects of aerobic exercise, resistance training, and combined exercise on the cardiovascular risks in pediatric obesity. This review outlines the evidence that exercise intervention is a beneficial therapeutic strategy to reduce the risk factors for CVD and the ideal exercise prescription to combat pediatric obesity should contain both muscle strengthening and aerobic components with an emphasis on fat mass reduction and long-term adherence.

Post-Transplant Diabetes Mellitus and Prediabetes in Renal Transplant Recipients: An Update

Post-transplant diabetes mellitus (PTDM) is a frequent and relevant complication after renal transplantation: it affects 20-30% of renal transplant recipients and increases the risk for cardiovascular and infectious events. Thus, understanding pathogenesis of PTDM would help limiting its consequences. In this review, we analyse novel aspects of PTDM, based on studies of the last decade, such as the clinical evolution of PTDM, early and late, the reversibility rate, diagnostic criteria, risk factors, including pre-transplant metabolic syndrome and insulin resistance (IR) and the interaction between these factors and immunosuppressive medications. Also, we discuss novel pathogenic factors, in particular the role of β-cell function in an environment of IR and common pathways between pre-existing cell damage and tacrolimus-induced toxicity. The relevant role of prediabetes in the pathogenesis of PTDM and cardiovascular disease is also addressed. Finally, current evidence on PTDM treatment is discussed.

Role of pregnancy on insulin-induced vasorelaxation: the influence of angiotensin II receptors

Insulin resistance is a feature of pregnancy and is associated with increased levels of angiotensin II (Ang II) and insulin. Therefore, pregnancy may change insulin-induced vasodilation through changes in Ang II receptors. Insulin-induced vasorelaxation was evaluated in phenylephrine-precontracted aortic rings of pregnant and non-pregnant rats, using a conventional isolated organ preparation. Experiments were performed in thoracic or abdominal aorta rings with or without endothelium in the presence and absence of N^G-nitro-L-arginine methyl ester (L-NAME) (10^-5 M), losartan (10^-7 M), or PD123319 (10^-7 M). AT1 and AT2 receptor expressions were detected by immunohistochemistry. Insulin-induced vasodilation was endothelium- and nitric oxide-dependent and decreased in the thoracic aorta but increased in the abdominal segment of pregnant rats. The insulin's vasorelaxant effect was increased by losartan mainly on the thoracic aorta. PD123319 decreased insulin-induced vasorelaxation mainly in the pregnant rat abdominal aorta. AT1 receptor expression was decreased while AT2 receptor expression was increased by pregnancy. In conclusion, pregnancy changes insulin-induced vasorelaxation. Moreover, insulin vasodilation is tonically inhibited by AT1 receptors, while AT2 receptors appear to have an insulin-sensitizing effect. The role of pregnancy and Ang II receptors differ depending on the aorta segment. These results shed light on the role of pregnancy and Ang II receptors on the regulation of insulin-mediated vasodilation.

Metabolite Profile of Treatment-Naive Metabolic Syndrome Subjects in Relation to Cardiovascular Disease Risk

Metabolic syndrome (MetSyn) is an important risk factor for type 2 diabetes and cardiovascular diseases (CVD). This study aimed to find distinct plasma metabolite profiles between insulin-resistant and non-insulin resistant subjects with MetSyn and evaluate if MetSyn metabolite profiles are related to CVD risk and lipid fluxes. In a cross-sectional study, untargeted metabolomics of treatment-naive males with MetSyn (n = 132) were analyzed together with clinical parameters. In a subset of MetSyn participants, CVD risk was calculated using the Framingham score (n = 111), and lipolysis (n = 39) was measured by a two-step hyperinsulinemic euglycemic clamp using [1,1,2,3,3-²H5] glycerol to calculate lipolysis suppression rates. Peripheral insulin resistance was related to fatty acid metabolism and glycerolphosphorylcholine. Interestingly, although insulin resistance is considered to be a risk factor for CVD, we observed that there was little correspondence between metabolites associated with insulin resistance and metabolites associated with CVD risk. The latter mainly belonged to the androgenic steroid, fatty acid, phosphatidylethanolamine, and phophatidylcholine pathways. These data provide new insights into metabolic changes in mild MetSyn pathophysiology and MetSyn CVD risk related to lipid metabolism. Prospective studies may focus on the pathophysiological role of the here-identified biomarkers.

Interorganelle communication, aging, and neurodegeneration

Our cells are comprised of billions of proteins, lipids, and other small molecules packed into their respective subcellular organelles, with the daunting task of maintaining cellular homeostasis over a lifetime. However, it is becoming increasingly evident that organelles do not act as autonomous discrete units but rather as interconnected hubs that engage in extensive communication through membrane contacts. In the last few years, our understanding of how these contacts coordinate organelle function has redefined our view of the cell. This review aims to present novel findings on the cellular interorganelle communication network and how its dysfunction may contribute to aging and neurodegeneration. The consequences of disturbed interorganellar communication are intimately linked with age-related pathologies. Given that both aging and neurodegenerative diseases are characterized by the concomitant failure of multiple cellular pathways, coordination of organelle communication and function could represent an emerging regulatory mechanism critical for long-term cellular homeostasis. We anticipate that defining the relationships between interorganelle communication, aging, and neurodegeneration will open new avenues for therapeutics.

EFFECT OF ADDING HOME-BASED MODERATE-INTENSITY EXERCISE ON METABOLIC FUNCTIONS IN OLDER ADULTS WITH NON-COMMUNICABLE DISEASES WHO REGULARLY PERFORM GYM-BASED MODERATE-INTENSITY EXERCISE

CONTEXT

Physical activity is important for the management of metabolic functions; however, little is known whether performing home-based moderate-intensity exercise (MIE) obtains further improvement on metabolic functions in adults with non-communicable diseases (NCDs) who already perform regular gym-based MIE.

OBJECTIVE

The purpose of this study was to examine the effect of adding home-based MIE on metabolic functions in older adults with NCDs who have regularly performed gym-based MIE.

DESIGN

This was a single-center randomized controlled study. The observation period was set for 24 weeks.

SUBJECTS AND METHODS

Twenty-one older adults (age, 60-79 years) with uncomplicated NCDs, who have performed 30-40 min MIE, 2-3 days/week at a hospital gym for over 1 year, were randomly divided into two groups: performing home-based MIE, comprising aerobic and resistance exercises, at least 20 min/day, 3 days/week (HOME, n = 11), or not performing home-based MIE (CON, n = 10). All participants completed the study and continued their gym-based MIE as usual.

RESULTS

After 24 weeks, there were no significant differences in the values of any outcomes. Conversely, the decrease in waist circumference (WC) was larger in the HOME group (-2.17 [-3.98, -0.36] cm) than in the CON group (0.57 [-1.42, 2.56] cm) (p < 0.05), although not in other outcomes.

CONCLUSIONS

Although further studies are needed, we found that adding home-based MIE had a positive effect on WC, but little effect on other metabolic functions in older adults with NCDs who have continued regular gym-based MIE.

Deletion of Rptor in Preosteoblasts Reveals a Role for the Mammalian Target of Rapamycin Complex 1 (mTORC1) Complex in Dietary-Induced Changes to Bone Mass and Glucose Homeostasis in Female Mice

The mammalian target of rapamycin complex 1 (mTORC1) complex is the major nutrient sensor in mammalian cells that responds to amino acids, energy levels, growth factors, and hormones, such as insulin, to control anabolic and catabolic processes. We have recently shown that suppression of the mTORC1 complex in bone‐forming osteoblasts (OBs) improved glucose handling in male mice fed a normal or obesogenic diet. Mechanistically, this occurs, at least in part, by increasing OB insulin sensitivity leading to upregulation of glucose uptake and glycolysis. Given previously reported sex‐dependent differences observed upon antagonism of mTORC1 signaling, we investigated the metabolic and skeletal effects of genetic inactivation of preosteoblastic‐mTORC1 in female mice. Eight‐week‐old control diet (CD)‐fed Rptor_ob^−/− mice had a low bone mass with a significant reduction in trabecular bone volume and trabecular number, reduced cortical bone thickness, and increased marrow adiposity. Despite no changes in body composition, CD‐fed Rptor_ob^−/− mice exhibited significant lower fasting insulin and glucose levels and increased insulin sensitivity. Upon high‐fat diet (HFD) feeding, Rptor_ob^−/− mice were resistant to a diet‐induced increase in whole‐body and total fat mass and protected from the development of diet‐induced insulin resistance. Notably, although 12 weeks of HFD increased marrow adiposity, with minimal changes in both trabecular and cortical bone in the female control mice, marrow adiposity was significantly reduced in HFD‐fed Rptor_ob^−/− compared to both HFD‐fed control and CD‐fed Rptor_ob^−/− mice. Collectively, our results demonstrate that mTORC1 function in preosteoblasts is crucial for skeletal development and skeletal regulation of glucose homeostasis in both male and female mice. Importantly, loss of mTORC1 function in OBs results in metabolic and physiological adaptations that mirror a caloric restriction phenotype (under CD) and protects against HFD‐induced obesity, associated insulin resistance, and marrow adiposity expansion. These results highlight the critical contribution of the skeleton in the regulation of whole‐body energy homeostasis. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Nutraceutical, Dietary, and Lifestyle Options for Prevention and Treatment of Ventricular Hypertrophy and Heart Failure

Although well documented drug therapies are available for the management of ventricular hypertrophy (VH) and heart failure (HF), most patients nonetheless experience a downhill course, and further therapeutic measures are needed. Nutraceutical, dietary, and lifestyle measures may have particular merit in this regard, as they are currently available, relatively safe and inexpensive, and can lend themselves to primary prevention as well. A consideration of the pathogenic mechanisms underlying the VH/HF syndrome suggests that measures which control oxidative and endoplasmic reticulum (ER) stress, that support effective nitric oxide and hydrogen sulfide bioactivity, that prevent a reduction in cardiomyocyte pH, and that boost the production of protective hormones, such as fibroblast growth factor 21 (FGF21), while suppressing fibroblast growth factor 23 (FGF23) and marinobufagenin, may have utility for preventing and controlling this syndrome. Agents considered in this essay include phycocyanobilin, N-acetylcysteine, lipoic acid, ferulic acid, zinc, selenium, ubiquinol, astaxanthin, melatonin, tauroursodeoxycholic acid, berberine, citrulline, high-dose folate, cocoa flavanols, hawthorn extract, dietary nitrate, high-dose biotin, soy isoflavones, taurine, carnitine, magnesium orotate, EPA-rich fish oil, glycine, and copper. The potential advantages of whole-food plant-based diets, moderation in salt intake, avoidance of phosphate additives, and regular exercise training and sauna sessions are also discussed. There should be considerable scope for the development of functional foods and supplements which make it more convenient and affordable for patients to consume complementary combinations of the agents discussed here. Research Strategy: Key word searching of PubMed was employed to locate the research papers whose findings are cited in this essay.

Hyperinsulinemia Induced Altered Insulin Signaling Pathway in Muscle of High Fat- and Carbohydrate-Fed Rats: Effect of Exercise

Insulin resistance is a state of impaired responsiveness to insulin action. This condition not only results in deficient glucose uptake but increases the risk for cardiovascular diseases (CVD), stroke, and obesity. The present work investigates the molecular mechanisms of high carbohydrate and fat diet in inducing prediabetic hyperinsulinemia and effect of exercise on InsR signaling events, muscular AChE, and lactate dehydrogenase activity. Adult male Wistar rats were divided into the control (C) diet group, high-carbohydrate diet (HCD) group, high-fat diet (HFD) group, and HCD and HFD groups with exercise (HCD Ex and HFD Ex, respectively). Acetyl choline esterase activity, lactate dehydrogenase activity, total lactate levels, IRS1 phosphorylations, and Glut4 expression patterns were studied in the muscle tissue among these groups. High carbohydrate and fat feeding led to hyperinsulinemic status with reduced acetylcholine esterase (AChE) activity and impaired phosphorylation of IRS1 along with increased lactate concentrations in the muscle. Exercise significantly upregulated phosphoinositide 3 kinase (PI3K) docking site phosphorylation and downregulated the negative IRS1 phosphorylations thereby increasing the glucose transporter (GLUT) expressions and reducing the lactate accumulation. Also, the levels of second messengers like IP3 and cAMP were increased with exercise. Increased second messenger levels induce calcium release thereby activating the downstream pathway promoting the translocation of GLUT4 to the plasma membrane. Our results showed that the metabolic and signaling pathway dysregulations seen during diet-induced hyperinsulinemia, a metabolic condition seen during the early stages in the development of prediabetes, were improved with vigorous physical exercise. Thus, exercise can be considered as an excellent management approach over drug therapy for diabetes and its complications.

Metabolic Syndrome: Prevalence and Risk Factors among Adolescent Female Intermediate and Secondary Students in Saudi Arabia

Background: Metabolic syndrome (MS) has become one of the major challenges to public health worldwide due to its significant association with increased risk of developing type 2 diabetes and cardiovascular disease (CVD) among children and adolescents. Therefore, this study aims to determine the prevalence and risk factors of MS in Saudi adolescents. Methods: This cross-sectional study was conducted in two female National Guard schools (Um Kalthoom Intermediate School and Zainab Bint Jahsh Secondary School) in Jeddah, Saudi Arabia, between January 2018 and March 2018. Of the 808 female students, 172 (age range of 12–19 years) participated voluntarily, with consent from their guardian(s), fasted for at least 8 h prior to the study, and represent the final study sample. Male students were not included due to cultural constraints in conducting the study. Demographic data, physical measurement (blood pressure, weight, height, body mass index (BMI) and waist circumference (WC)), and biochemical measurement (fasting plasma glucose and triglycerides, high-density lipoprotein (HDL), and low-density lipoprotein) were obtained. The International Diabetes Federation (IDF) criteria was utilized in the diagnosis of MS. Results: Of the 172 female adolescents, 24 (13.75%) are overweight, 20 (11.63%) are obese, and 3 (1.74%) are underweight. High-fasting plasma glucose (n = 85, 49.41%) and high waist circumference (n = 74, 43.02%) were the most common risk factors of MS among female adolescents. The overall prevalence of MS was 7% (n = 12/172). MS is more common among those who are obese or among those with a BMI that falls at the ≥95th percentile (n = 6/20, 30.0%) (p < 0.05) as compared to those who are overweight with a BMI that falls within the 85th to <95th percentiles (n = 2/24, 8.33%). Interestingly, 3.20% of the sample (n = 4/125) with normal BMI were diagnosed with MS. Conclusions: Our study indicates that MS is common among obese and overweight female adolescents but is also present among those who are not obese or with normal BMI. Moreover, the prevalence of overweight, obese, and those with MS in this reference population are lower compared to the cities of Makkah and Riyadh; however, it varies widely around the world due to different criteria and cut-off values in the diagnosis of MS.

Does insulin resistance influence neurodegeneration in non-diabetic Alzheimer's subjects?

Background

Type 2 diabetes is a risk factor for Alzheimer’s disease (AD), and AD brain shows impaired insulin signalling. The role of peripheral insulin resistance on AD aetiopathogenesis in non-diabetic patients is still debated. Here we evaluated the influence of insulin resistance on brain glucose metabolism, grey matter volume and white matter lesions (WMLs) in non-diabetic AD subjects.

Methods

In total, 130 non-diabetic AD subjects underwent MRI and [18F]FDG PET scans with arterial cannula insertion for radioactivity measurement. T1 Volumetric and FLAIR sequences were acquired on a 3-T MRI scanner. These subjects also had measurement of glucose and insulin levels after a 4-h fast on the same day of the scan. Insulin resistance was calculated by the updated homeostatic model assessment (HOMA2). For [18F]FDG analysis, cerebral glucose metabolic rate (rCMRGlc) parametric images were generated using spectral analysis with arterial plasma input function.

Results

In this non-diabetic AD population, HOMA2 was negatively associated with hippocampal rCMRGlc, along with total grey matter volumes. No significant correlation was observed between HOMA2, hippocampal volume and WMLs.

Conclusions

In non-diabetic AD, peripheral insulin resistance is independently associated with reduced hippocampal glucose metabolism and with lower grey matter volume, suggesting that peripheral insulin resistance might influence AD pathology by its action on cerebral glucose metabolism and on neurodegeneration.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13195-021-00784-w.

Renaming NAFLD to MAFLD: Could the LDE System Assist in This Transition?

Our understanding of fatty liver syndromes and their relationship with the metabolic syndrome has improved over recent decades and, paralleling this, we are now at the dawn of the NAFLD (nonalcoholic fatty liver disease) to MAFLD (metabolic-associated fatty liver disease) transition. The pitfalls of NAFLD diagnosis, together with disappointing results in therapeutic trials, and the inconsistencies and risks inherent in a "negative" definition (such as "nonalcoholic") as opposed to a "positive" one (i.e., "metabolic") are predicted to facilitate the proposed renaming of NAFLD to MAFLD. However, a premature change of terminology would not necessarily address major unmet needs in this area, and may even become counterproductive. As an aid to selecting more homogeneous cohorts of patients, I propose the LDE (Liver, Determinants, Extra-hepatic) classification system which, in principle, may help to assess the natural course of disease as well as the efficacy of novel drugs in patients with NAFLD/MAFLD.

Plasma ghrelin, adiponectin and leptin levels in obese rats with type 2 diabetes mellitus after sleeve gastrectomy and gastric plication

The prevalence of obesity has increased in recent decades and has become a public health problem. In obesity patients the metabolism of almost all adipokines is markedly dysregulated. Studies regarding levels of ghrelin, leptin, and adiponectin after bariatric surgery reveal contradictory results. The purpose of the present study was to analyze modification of body weight and plasma levels of fasting glucose, ghrelin, adiponectin and leptin, in obese rats with T2DM after sleeve gastrectomy (SG), gastric plication (GP) and sham-operated (SO). Eighteen specimens where randomized to three weight-matched groups: Group SG underwent sleeve gastrectomy (n=6), group GP underwent gastric plication (n=6) and the control group SO underwent sham surgery (n=6). Upon surgery a normal rat chow diet (Bio-Serv^® product no. F4031) was fed to the rats until the end of the experiment. Additional blood samples were harvested after 4 weeks. The results revealed that body mass decreased in the SG (783.17±101.39 vs. 658.33±86.57 g; P<0.0001) and the GP (781.33±103.12 vs. 702.33±84.06 g; P=0.004) rats after surgery. There were significant lower fasting glucose levels at 4 weeks postoperative in the SG group compared to the SO group (83.1±12.81 vs. 104.5±9.81 mg/dl; P=0.016). The same trend was observed in the GP group vs. the SO group (86.7±11.43 vs. 104.5±9.81 mg/dl; P=0.026). There was no difference regarding mean glucose levels between the SG group compared to the GP group (P>0.05). Plasma acylated ghrelin and leptin levels decreased four weeks after surgery compared to preoperative levels, while adiponectin levels increased four weeks after surgery in the SG and GP groups, respectively. The present study revealed that plasma glucose levels, ghrelin and leptin levels decreased after SG and GP, while adiponectin levels improved. This suggests that there may be hormonal contribution in weight loss.

Joint effect of high blood pressure and physical inactive on diabetes mellitus: a population-based cross-sectional survey

Introduction

The relationship of high blood pressure and physical inactivity to diabetes mellitus is well known, but not many studies have known the joint effect of the two in causing diabetes mellitus. This study aims to evaluate the joint effect of high blood pressure and less physical activity against Diabetes Mellitus (DM) in Indonesia.

Methods

This is a cross-sectional study. Subjects in this study were the age group ≥ 21 years old who were followed by the interview. We investigated factors related to DM in Indonesia associated with blood pressure and physical activity by controlling other confounding variables. Statistical analyses were conducted using logistic regression. Age, sex, education level, marital status, occupation, body mass index, residence area, stress, fruit, and vegetable consumption were adjusted for in the multivariate model.

Results

The prevalence of DM was 3.86% among respondents. Multivariate analysis showed that people who had hypertension and less physical activity had a risk of 3.68 (95% CI, 2.43-5.34) times having DM. People who had hypertension and enough physical activity had a risk of 2.33 (95% CI, 1.65-6.43) times having DM. While people who do not have hypertension and had less physical activity had a risk of 1.81 (95% CI, 1.34-3.62) times.

Conclusions

People with hypertension and less physical activity have the greatest risk of developing DM.

Lifestyle Modification with Physical Activity Promotion on Leptin Resistance and Quality of Life in Metabolic Syndrome - A Systematic Review with Meta-Analysis

OBJECTIVE

This study focused to systematically extract, summarize and analyse the data on the effect of lifestyle modification on leptin resistance and quality of life in metabolic syndrome.

METHODS

The systematic search was done using PubMed, Cochrane Database, EMBASE, Science Direct, CINAHL, Springer link, Web of Science from 2000-2018. English language articles and quantitative studies focusing on leptin resistance and quality of life were included. Random effect analysis was adopted to pool data and estimate 95% CI. The meta-analysis was done separately for leptin resistance and quality of life which included a total of 9 studies on both RCTs and Non-RCTs.

RESULTS

The meta-analysis of RCTs reported insignificant effect of lifestyle modification on leptin resistance in metabolic syndrome when compared to comparison group (-5.94(-14.28, 2.41). Two clinical trials showed a significant effect with pooled data (5.52(2.14, 8.91). Meta-analysis of RCTs focusing on quality of life showed significant effect on mental component (4.89 (0.16, 9.62) of quality of life (2.36 (-3.67, 8.39) when compared to comparison group.

CONCLUSION

This meta-analysis suggested that lifestyle modification has a potential to improve leptin resistance and mental component of quality of life in metabolic syndrome. However, more clearly defined studies are required to come to a stronger conclusion.

Effect of Metformin on Breast Density in Overweight/Obese Premenopausal Women

BACKGROUND

This study investigated the effects of metformin on breast density in overweight/obese premenopausal women.

METHODS

Overweight/obese premenopausal women (n=120) were randomly assigned to the metformin or placebo group, and all women received lifestyle interventions. The outcomes included weight, BMI, FPG, FIN, glucose, HOMA-IR, LDL-C, HDL-C, TG, TC, SBP, DBP, FSH, E, AD, and the BIRADS grade, and the incidence of breast cancer was assessed by pathological biopsy and BIRADS grade greater than 4.

RESULTS

In total, 120 overweight/obese women completed the 1-year trial. Seven patients had a BIRADS grade greater than 4, including 5 patients who were biopsy positive, in the control group, and 2 patients had a BIRADS grade greater than 4, including 1 patient who was biopsy positive, in the metformin group. Compared with those in the control group, the body weight, BMI, FIN, FPG, HOMA-IR, TC, BIRADS grade and positive pathological biopsy rate in the metformin group were significantly decreased (P<0.05), while AD was significantly increased (P<0.05). The correlation analysis indicated that the BIRADS grade was significantly correlated with weight, BMI, FPG, FIN, HOMA-IR, SBP, AD and the positive pathological biopsy rate, and the positive pathological biopsy rate was significantly correlated with weight, BMI, HOMA-IR, SBP, AD and BIRADS grade. The logistic regression analysis revealed that the BIRADS grade was significantly correlated with the positive pathological biopsy rate and AD and that the positive pathological biopsy rate was significantly correlated with the BIRADS grade.

CONCLUSION

As adjunctive therapy, the combination of lifestyle changes and metformin was found to be a safe strategy for improving related metabolic markers and increasing adiponectin. The BIRADS grade was significantly correlated with the positive pathological biopsy rate and AD, and the positive pathological biopsy rate was significantly correlated with the BIRADS grade.

National School-Based Health Lifestyles Intervention in Chinese Children and Adolescents on Obesity and Hypertension

Introduction: This study aimed to examine the effectiveness of the national school-based intervention on both obesity and high blood pressure in Chinese children and adolescents aged 6-18 years. Methods: The national school-based cluster non-randomized controlled trial was done in seven provinces from September 2013 to February 2014. A total of 23,175 children and adolescents in the control group and 25,702 in the intervention group were included in this trial with a mean follow-up of 6.7 ± 0.9 months. Mixed-effects regression models were used to evaluate the effect of the interventions on body weight and blood pressure (BP). Results: A significant upward in the body mass index (BMI) levels but downward in systolic BP (SBP), diastolic BP (DBP), BMI Z-scores, SBP Z-scores, and DBP Z-scores were witnessed in the intervention group compared to those in the control group (<0.001). Subgroup analyses presented significant intervention effects in children aged 6-12 years for BMI, SBP, DBP, and their standardized values Z-scores, but no effective results were found in adolescents aged 13-18 years. Stratification analyses based on the dynamic weight changes presented non-differential HBP, SHBP, and DHBP prevalence gaps between the control and intervention groups. Children aged 6-12 years with higher BMI percentiles at baseline presented obvious declines in SBP and DBP standardized values Z-scores. Conclusion: A mean 6-month multi-centered school-based comprehensive obesity intervention in China yields a small to null effect on obesity and hypertension with increasing age; the early age before 12 years may be the key period for interventions, and the younger, the better. Precise and high-intensity interventions targeting the population at different stages of childhood and adolescence are urgently needed to be developed. Clinical Trial Registration: https://www.clinicaltrials.gov/, identifier: NCT02343588.

Effect of growth hormone on insulin signaling

Growth hormone (GH) is a pleiotropic hormone that coordinates an array of physiological processes, including effects on bone, muscle, and fat, ultimately resulting in growth. Metabolically, GH promotes anabolic action in most tissues except adipose, where its catabolic action causes the breakdown of stored triglycerides into free fatty acids (FFA). GH antagonizes insulin action via various molecular pathways. Chronic GH secretion suppresses the anti-lipolytic action of insulin and increases FFA flux into the systemic circulation; thus, promoting lipotoxicity, which causes pathophysiological problems, including insulin resistance. In this review, we will provide an update on GH-stimulated adipose lipolysis and its consequences on insulin signaling in liver, skeletal muscle, and adipose tissue. Furthermore, we will discuss the mechanisms that contribute to the diabetogenic action of GH.

Effect of moderate-intensity seated exercise on the management of metabolic outcomes in hypertensive individuals with or without exercise habits

Background

We aimed to evaluate the effect of moderate-intensity seated exercise on metabolic outcomes in hypertensive individuals with or without exercise habits.

Methods

Forty-two hypertensive individuals volunteered for this study and were classified into 3 groups by their habits and place for moderate-intensity exercise prior to this study: NONE (<2 days/week or no exercise; n = 13), HOME (≥30 min/day and ≥2 days/week at home; n = 15), and GYM (≥30 min/day and ≥2 days/week at a hospital gym; n = 14). They performed their daily activities as usual and seated exercise (stepping and stepping with trunk rotation; a range of 11–13 on the Borg rating of perceived exertion scale) for at least 15 min/day and at least 3 days/week for 12 weeks.

Results

Thirty-five participants (age: 67.7 ± 5.9 years) completed the study, and there was no difference among the 3 groups regarding weekly exercise. The homeostasis model assessment of insulin resistance (HOMA-IR) value in the NONE group was significantly higher than that in the GYM group at baseline (p < 0.05), but it decreased significantly after 12 weeks (from 2.2 ± 0.8 to 1.7 ± 0.7, p < 0.05). Changes in HOMA-IR in the NONE group after 12 weeks was greater than that in the HOME and GYM groups (both p < 0.01). The HOME and GYM groups showed no significant changes in any of the variables.

Conclusion

Moderate-intensity seated exercise may be an effective strategy to improve insulin resistance in hypertensive individuals without exercise habits.

Diet to Reduce the Metabolic Syndrome Associated with Menopause. The Logic for Olive Oil

The rates of metabolic syndrome are increasing in parallel with the increasing prevalence of obesity, primarily due to its concomitant insulin resistance. This is particularly concerning for women, as the years around menopause are accompanied by an increase in visceral obesity, a strong determinant of insulin resistance. A fall in estrogens and increase in the androgen/estrogen ratio is attributed a determining role in this process, which has been confirmed in other physiological models, such as polycystic ovary syndrome. A healthy lifestyle, with special emphasis on nutrition, has been recommended as a first-line strategy in consensuses and guidelines. A consistent body of evidence has accumulated suggesting that the Mediterranean diet, with olive oil as a vital component, has both health benefits and acceptable adherence. Herein, we provide an updated overview of current knowledge on the benefits of olive oil most relevant to menopause-associated metabolic syndrome, including an analysis of the components with the greatest health impact, their effect on basic mechanisms of disease, and the state of the art regarding their action on the main features of metabolic syndrome.

Aortic Pulse Wave Velocity, Ankle-Brachial Index, and Malondialdehyde in Older Adults with or without Metabolic Syndrome

Metabolic syndrome is an important health problem associated with both subclinical atherosclerosis and an increased risk of cardiovascular disease and it leads to an elevated total mortality. Aortic pulse wave velocity (aPWV) is widely used for noninvasive assessment of arterial stiffness. Ankle-brachial index (ABI) predicts peripheral arterial disease (PAD) of the lower extremities. In addition, malondialdehyde (MDA) is thought to be involved in the development of arterial stiffness. The present study aimed to: (1) compare aPWV, ABI, and MDA between participants with MetS and those without MetS and (2) investigate the correlation of aPWV and ABI with the components of MetS and MDA. A total of 48 Thai elderly subjects were divided into 2 groups (MetS and non-MetS) according to the parameters set by the International Diabetes Federation (IDF). aPWV and ABI were measured using the VaSera VS-1500 system (Fukuda Denshi Co., Tokyo, Japan). MDA was determined by spectrophotometry. aPWV and MDA were significantly higher in the MetS group compared to the participants in the non-MetS group (9.33 ± 2.72 vs. 7.95 ± 1.37 m/s, p = 0.03, and 0.74 ± 0.71 vs. 0.45 ± 0.20 μmol, p = 0.02, respectively). However, ABI did not differ between the groups. Analysis of the risk factors of aPWV in each group revealed that there were no statistical associations between the components of MetS and MDA and aPWV in both the MetS and the non-MetS groups. A high aPWV is more prevalent among patients with MetS than among those without MetS. Monitoring of aPWV might help to explore potential detection of vascular damage in the elderly.

Lipoprotein insulin resistance score in nondiabetic patients with obesity after bariatric surgery

BACKGROUND

Lipoprotein insulin resistance (LPIR) score is a composite biomarker representative of atherogenic dyslipidemia characteristic of early insulin resistance. It is elevated in obesity and may provide information not captured in glycosylated hemoglobin and homeostatic model assessment for insulin resistance. While bariatric surgery reduces diabetes incidence and resolves metabolic syndrome, the effect of bariatric surgery on LPIR is untested.

OBJECTIVES

We sought to assess the effects of Roux-en-Y gastric bypass and sleeve gastrectomy on LPIR in nondiabetic women with obesity.

SETTING

Nonsmoking, nondiabetic, premenopausal Hispanic women, age ≥18 years, undergoing Roux-en-Y gastric bypass or sleeve gastrectomy at Bellevue Hospital were recruited for a prospective observational study.

METHODS

Anthropometric measures and blood sampling were performed preoperatively and at 6 and 12 months postoperatively. LPIR was measured by nuclear magnetic resonance spectroscopy.

RESULTS

Among 53 women (Roux-en-Y gastric bypass, n = 22; sleeve gastrectomy, n = 31), mean age was 32 ± 7 years and body mass index 44.1 ± 6.4 kg/m2. LPIR was reduced by 35 ± 4% and 46 ± 4% at 6 and 12 months after surgery, respectively, with no difference by procedure. Twenty-seven of 53 patients met International Diabetes Federation criteria for metabolic syndrome preoperatively and had concomitant higher homeostatic model assessment for insulin resistance, glycosylated hemoglobin, nonhigh-density lipoprotein-cholesterol and LPIR. Twenty-five of 27 patients experienced resolution of metabolic syndrome postoperatively. Concordantly, the preoperative differences in homeostatic model assessment for insulin resistance, glycosylated hemoglobin, and nonhigh-density lipoprotein-cholesterol between those with and without metabolic syndrome resolved at 6 and 12 months. In contrast, patients with metabolic syndrome preoperatively exhibited greater LPIR scores at 6 and 12 months postoperatively.

CONCLUSION

This is the first study to demonstrate improvement in insulin resistance, as measured by LPIR, after bariatric surgery with no difference by procedure. This measure, but not traditional markers, was persistently higher in patients with a preoperative metabolic syndrome diagnosis, despite resolution of the condition.

Weekly variation in markers of cardiometabolic health - the possible effect of weekend behavior - a cross-sectional study

Background

Adolescents’ health-related behavior varies from weekday to weekend. Only few studies, however, have examined to which degree such variation will affect markers of cardiometabolic health. Therefore, the primary aim of this study is to examine if markers of cardiometabolic health differ between different days of the week in adolescents.

Methods

This cross-sectional school-based study included up to 581 participants, 11–17 years old. Markers of metabolic health were insulin, glucose, triglyceride, HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C) and blood pressure. Linear mixed regression modelling was used to examine the cardiometabolic profile across weekdays.

Results

Significant declining trends were observed across the week in adolescents’ levels of cardiometabolic health markers. Lower levels of insulin (16.1%), glucose (2.6%) and triglyceride (24.7%) were observed on Fridays compared to Mondays (p ≤ 0.006). Gradual improvement in measurement profiles across weekdays was less apparent for HDL-C, LDL-C, systolic blood pressure and diastolic blood pressure (P ≥ 0.06). Analyses stratified by sex suggested a more noticeable pattern of gradual improvement across weekdays in boys than in girls.

Conclusion

Significantly lower levels of insulin, glucose and triglyceride were observed in adolescents on Fridays compared to Mondays. However, when sex specific analyses were performed significant profile variations were only observed across the week in boys. More research is needed to better understand which behavioral factors in particular seem to influence weekly variation in markers of cardiometabolic health - especially since such variation potentially will have an impact on how assessments of markers of cardiometabolic health optimally should be planned, standardized and carried out, both in research and in medical practice.

Emerging Links between Cadmium Exposure and Insulin Resistance: Human, Animal, and Cell Study Data

Recent research has helped clarify the role of cadmium (Cd) in various pathological states. We have demonstrated Cd involvement in pancreatic cancer, as well as the bioaccumulation of Cd in the pancreas. Bioaccumulation and increased toxicity suggest that Cd may also be involved in other pancreas-mediated diseases, like diabetes. Cd falls into the category of "hyperglycemic" metals, i.e., metals that increase blood glucose levels, which could be due to increased gluconeogenesis, damage to β-cells leading to reduced insulin production, or insulin resistance at target tissue resulting in a lack of glucose uptake. This review addresses the current evidence for the role of Cd, leading to insulin resistance from human, animal, and in vitro studies. Available data have shown that Cd may affect normal insulin function through multiple pathways. There is evidence that Cd exposure results in the perturbation of the enzymes and modulatory proteins involved in insulin signal transduction at the target tissue and mutations of the insulin receptor. Cd, through well-described mechanisms of oxidative stress, inflammation, and mitochondrial damage, may also alter insulin production in β-cells. More work is necessary to elucidate the mechanisms associated with Cd-mediated insulin resistance.

Farnesoid X Receptor Agonists as Therapeutic Target for Cardiometabolic Diseases

Cardiometabolic diseases are characterized as a combination of multiple risk factors for cardiovascular disease (CVD) and metabolic diseases including diabetes mellitus and dyslipidemia. Cardiometabolic diseases are closely associated with cell glucose and lipid metabolism, inflammatory response and mitochondrial function. Farnesoid X Receptor (FXR), a metabolic nuclear receptor, are found to be activated by primary BAs such as chenodeoxycholic acid (CDCA), cholic acid (CA) and synthetic agonists such as obeticholic acid (OCA). FXR plays crucial roles in regulating cholesterol homeostasis, lipid metabolism, glucose metabolism, and intestinal microorganism. Recently, emerging evidence suggests that FXR agonists are functional for metabolic syndrome and cardiovascular diseases and are considered as a potential therapeutic agent. This review will discuss the pathological mechanism of cardiometabolic disease and reviews the potential mechanisms of FXR agonists in the treatment of cardiometabolic disease.

Substitution of parts of aerobic training by resistance training lowers fasting hyperglycemia in individuals with metabolic syndrome

We sought to determine the effects of substituting parts of aerobic training (AT) by resistance training (RT) on metabolic syndrome (MetS) factors. MetS patients (aged 56 ± 7 years; body mass index 33 ± 5 kg·m^-2 and 3.9 ± 0.8 MetS factors) were randomized to undergo 1 of the following isocaloric, 16-week long exercise programs: (i) cycling 4 bouts of 4-min at 90% of maximal heart rate (HR_max) followed by 3 sets of 12 repetitions of 3 lower limb free-weight exercises (high-intensity interval training (HIIT)+RT group; n = 33), (ii) cycling 5 bouts of 4 min at 90% of HR_max (HIIT+HIIT group; n = 33), or (iii) no exercise control group (n = 21). We measured the evolution of all 5 MetS components (z score), cardiorespiratory fitness (maximal oxygen uptake), leg strength and power (leg press 1-repetition maximum (1RM) and countermovement jump (CMJ)), fasting blood glucose (FG), fasting insulin, and insulin resistance (homeostasis model assessment 2). Both training groups improved maximal oxygen uptake similarly (170 ± 310 and 190 ± 210 mL O₂·min^-1; P < 0.001) and z score (-0.12 ± 0.29 and -0.12 ± 0.31 for HIIT+RT and HIIT+HIIT, respectively; P < 0.02). However, only HIIT+RT improved CMJ (P = 0.002) and leg press 1RM above the HIIT+HIIT group (21% vs 6%; P < 0.001). Furthermore, FG only decreased in the HIIT+RT group (5%; P = 0.026, time × group). Our findings suggest that substitution of part of HIIT by leg RT improves glucose control in MetS individuals. Novelty Most studies addressing the efficacy of endurance versus resistance training are not matched by energy expenditure. We found that substituting 20% of AT with RT reduces hyperglycemia in MetS individuals. Training recommendations to regain glycemic control in MetS individuals should include resistance training.

Prevalence of Insulin Resistance in the Hungarian General and Roma Populations as Defined by Using Data Generated in a Complex Health (Interview and Examination) Survey

Data mainly from one-off surveys clearly show that the health of Roma, the largest ethnic minority of Europe, is much worse than that of the general population. However, results from comprehensive exploratory studies are missing. The aim of our study was to create a complex database for comparative and association studies to better understand the background of the very unfavourable health of Roma, especially the high burden of cardiometabolic diseases. A three-pillar (questionnaire-based, physical and laboratory examinations) health survey was carried out on randomly selected samples of the Hungarian general (HG, n = 417) and Roma (HR, n = 415) populations, and a database consisting of more than half a million datapoints was created. Using selected data, the prevalence rates of metabolic syndrome (MetS) and of its components were determined, and to estimate the risk of insulin resistance (IR), surrogate measures (the homeostasis model assessment of insulin resistance index, quantitative insulin sensitivity check index, McAuley and TyG indices and the TG/HDL-C ratio) were calculated. Receiver operating characteristic curve analysis and Youden’s method were used to define the optimal cut-off values of each IR index. The prevalence of MetS was very high in both study populations (HG: 39.8%, HR: 44.0%) with no statistically significant difference between the two groups in females or males. The prevalence of MetS showed a very marked increase in the HR 35–49 years age group. Among surrogate measures, the TyG index showed the greatest power for predicting IR/MetS at a cut-off value of 4.69 (77% sensitivity, 84% specificity) and indicated a 42.3% (HG) and 40.5% (HR) prevalence of IR. The prevalence of MetS and IR is almost equally very unfavourable in both groups; thus, the factors underlying the high premature mortality burden of Roma should be further clarified by investigating the full spectrum of risk factors available in the database, with a special focus on the access of Roma people to preventive and curative health services.

Extracellular vesicles released by adipose tissue-derived mesenchymal stromal/stem cells from obese pigs fail to repair the injured kidney

AIMS

Mesenchymal stromal/stem cell (MSC)-derived extracellular vesicles (EVs) shuttle select MSC contents and are endowed with an ability to repair ischemic tissues. We hypothesized that exposure to cardiovascular risk factors may alter the microRNA cargo of MSC-derived EVs, blunting their capacity to repair the post-stenotic kidney in pigs with metabolic syndrome (MetS) and renal artery stenosis (RAS).

METHODS

Porcine MSCs were harvested from abdominal fat after 16wks of Lean- or MetS-diet, and their EVs isolated and characterized using microRNA-sequencing. Lean- and MetS-EV protective effects were assessed in-vitro in human umbilical endothelial cells (HUVECs). To compare their in-vivo efficacy to repair ischemic tissues, allogeneic-EVs were intrarenally delivered in pigs after 6wks of MetS + RAS, and 4wks later, single-kidney renal blood flow (RBF) and glomerular filtration rate (GFR) were studied in-vivo, and microvascular architecture and injury ex-vivo. Lean-, MetS-, and MetS + RAS-sham served as controls (n = 6 each).

RESULTS

Ten microRNAs, capable of targeting several pro-angiogenic genes, were upregulated in MetS-EVs versus Lean-EVs. In vitro, MetS-EVs failed to increase tube number and length, and to boost HUVEC migration compared to Lean-EVs. Lean- and MetS-EVs were detected in the stenotic-kidney 4wks after injection in the vicinity of small vessels. RBF and GFR were lower in MetS + RAS versus MetS, and restored in MetS + RAS + Lean-EVs, but not in MetS + RAS + MetS-EVs. Furthermore, MetS-EVs failed to restore renal expression of angiogenic factors, improve microvascular density, or attenuate fibrosis.

CONCLUSIONS

MetS alters the microRNA cargo of MSC-derived EVs and impairs their functional potency, limiting the therapeutic efficacy of this endogenous cellular repair system.

Effect of Hesperidin on Cardiovascular Disease Risk Factors: The Role of Intestinal Microbiota on Hesperidin Bioavailability

Recently, hesperidin, a flavonone mainly present in citrus fruits, has emerged as a new potential therapeutic agent able to modulate several cardiovascular diseases (CVDs) risk factors. Animal and in vitro studies demonstrate beneficial effects of hesperidin and its derived compounds on CVD risk factors. Thus, hesperidin has shown glucose-lowering and anti-inflammatory properties in diabetic models, dyslipidemia-, atherosclerosis-, and obesity-preventing effects in CVDs and obese models, and antihypertensive and antioxidant effects in hypertensive models. However, there is still controversy about whether hesperidin could contribute to ameliorate glucose homeostasis, lipid profile, adiposity, and blood pressure in humans, as evidenced by several clinical trials reporting no effects of treatments with this flavanone or with orange juice on these cardiovascular parameters. In this review, we focus on hesperidin's beneficial effects on CVD risk factors, paying special attention to the high interindividual variability in response to hesperidin-based acute and chronic interventions, which can be partly attributed to differences in gut microbiota. Based on the current evidence, we suggest that some of hesperidin's contradictory effects in human trials are partly due to the interindividual hesperidin variability in its bioavailability, which in turn is highly dependent on the α-rhamnosidase activity and gut microbiota composition.

Stat3 activation induces insulin resistance via a muscle-specific E3 ubiquitin ligase Fbxo40

Cellular mechanisms causing insulin resistance (IR) in chronic kidney disease (CKD) are poorly understood. One potential mechanism is that CKD-induced inflammation activates the signal transducer and activator of transcription 3 (Stat3) in muscle. We uncovered increased p-Stat3 in muscles of mice with CKD or mice fed high-fat diet (HFD). Activated Stat3 stimulates the expression of Fbxo40, a muscle-specific E3 ubiquitin ligase that stimulates ubiquitin conjugation leading to degradation of insulin receptor substrate 1 (IRS1). Evidence that Stat3 activates Fbxo40 includes 1) potential Stat3 binding sites in Fbxo40 promoters; 2) Stat3 binding to the Fbxo40 promoter; and 3) constitutively active Stat3 stimulating both Fbxo40 expression and its promoter activity. We found that IL-6 activates Stat3 in myotubes, increasing Fbxo40 expression with reduced IRS1 and p-Akt. Knockdown Fbxo40 using siRNA from myotubes results in higher levels of IRS1 and p-Akt despite the presence of IL-6. We treated mice with a small-molecule inhibitor of Stat3 (TTI-101) and found improved glucose tolerance and insulin signaling in skeletal muscles of mice with CKD or fed an HFD. Finally, we uncovered improved glucose tolerance in mice with muscle-specific Stat3 KO versus results in Stat3^f/f mice in response to the HFD. Thus Stat3 activation in muscle increases IR in mice. Inhibition of Stat3 by TTI-101 could be developed into clinical strategies to improve muscle insulin signaling in inflammation and other catabolic diseases.

Association of One-Leg Standing Time with Discontinuation of Injectable Medications During Hospitalization Among Patients with Type 2 Diabetes

INTRODUCTION

Persons with type 2 diabetes (T2D) are known to experience impaired physical ability even at the early stages of the disease. However, less attention has been paid to increasing physical ability than to increasing physical activity in the treatment of T2D. The aim of this study was to assess whether improved physical ability parameters are associated with the discontinuation of injectable medications once glycemic targets have been achieved among inpatients with inadequately controlled T2D across a wide range of ages.

METHODS

Forty-three patients with glycated hemoglobin levels of ≥ 7.5% (58 mmol/mol) aged between 19 and 82 years who received insulin, glucagon-like peptide-1 receptor agonists or both at admission were enrolled in the study. Muscle strength for knee extension, one-leg standing time with eyes open test(OLST), whole-body reaction time and maximal oxygen uptake were assessed as parameters of physical ability.

RESULTS

At admission, patients who during hospitalization discontinued injectable medications (n = 29; Discontinued group) had a shorter duration of diabetes, lower fat mass and higher skeletal muscle mass and performed better on all of the physical ability test parameters than those who continued on injectable medications during hospitalization (n = 14; Continued group). At discharge, patients in the Discontinued group had achieved better glycemic control than those in the Continued group, as indicated by lower mean plasma glucose levels according to the 7-point profile. Stepwise logistic regression analysis that included those variables that were significantly different between the Continued group and the Discontinued group, with the aim to identify candidate(s) of explanatory variables, revealed that only OLST was significantly associated with the discontinuation of injectable medication. Patients with an OLST of ≥ 60 s were more likely to discontinue injectable medication than those with an OLST of < 60 s (odds ratio 18.9; 95% confidence interval 2.0-178.8; p = 0.011).

CONCLUSIONS

Among inpatients with inadequately controlled T2D diabetes, longer OLST appear to be associated with discontinuing injectable medications during hospitalization. OLST could possibly be useful as a novel patient factor to consider in de-intensifying injectable medication.

Mediterranean diet as medical prescription in menopausal women with obesity: a practical guide for nutritionists

Menopausal transition is associated with weight gain and increased visceral fat distribution, which acts as an endocrine organ secreting the pro-inflammatory adipocytokines, which leads to metabolic disorders typical of menopause, including type 2 diabetes and cardiovascular diseases. Given the increasing number of aging population, the nutritional strategies to prevent obesity and obesity-related diseases in menopausal women is becoming a growing need and it should be one of the main objective for Nutritionists. The Mediterranean diet is characterized from foods with anti-inflammatory and antioxidant actions, such as extra-virgin olive oil, vegetables, fruits, legumes, nuts, red wine, and whole-grain cereals. Several evidences showed that the Mediterranean diet acts on both weight control and menopause, in addition to the known effects of the Mediterranean diet on cardiovascular and metabolic diseases. The Mediterranean diet is comparable with pharmacological interventions in terms of reducing the risk of obesity and cardiovascular and metabolic events. Considering that there are no specific dietary guidelines to manage weight in menopause, the aim of this review is to provide a nutritional guideline for the management of weight in menopause, particularly focusing on the Mediterranean diet.

Biohumoral Indicators Influenced by Physical Activity in the Elderly

In the scientific landscape, there is a growing interest in defining the role of several biomolecules and humoral indicators of the aging process and in the modifications of these biomarkers induced by physical activity and exercise. The main aim of the present narrative review is to collect the available evidence on the biohumoral indicators that could be modified by physical activity (PA) in the elderly. Online databases including Pubmed, Web of science (Medline), and Scopus were searched for relevant articles published in the last five years in English. Keywords and combination of these used for the search were the following: “biological”, “indicators”, “markers”, “physical”, “activity”, and “elderly”. Thirty-four papers were analyzed for inclusion. Twenty-nine studies were included and divided into four categories: cardiovascular (CV) biomarkers, metabolic biomarkers, inflammatory markers-oxidative stress molecules, and other markers. There are many distinct biomarkers influenced by PA in the elderly, with promising results concerning the metabolic and CV indexes, as a growing number of studies demonstrate the role of PA on improving parameters related to heart function and CV risk like atherogenic lipid profile. Furthermore, it is also a verified hypothesis that PA is able to modify the inflammatory status of the subject by decreasing the levels of pro-inflammatory cytokines, including interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). PA seems also to be able to have a direct effect on the immune system. There is a strong evidence of a positive effect of PA on the health of elderly people that could be evidenced and “quantified” by the modifications of the levels of several biohumoral indicators.

3-Iodothyronamine and Derivatives: New Allies Against Metabolic Syndrome?

In the two decades since its discovery, a large body of evidence has amassed to highlight the potential of 3-iodothyronamine (T1AM) as an antiobesity drug, whose pleiotropic signaling actions profoundly impact energy metabolism. In the present review, we recapitulate the most relevant properties of T1AM, including its structural and functional relationship to thyroid hormone, its endogenous levels, molecular targets, as well as its genomic and non-genomic effects on metabolism elicited in experimental models after exogenous administration. The physiological and pathophysiological relevance of T1AM in the regulation of energy homeostasis and metabolism is also discussed, along with its potential therapeutic applications in metabolic disturbances. Finally, we examine a number of T1AM analogs that have been recently developed with the aim of designing novel pharmacological agents for the treatment of interlinked diseases, such as metabolic and neurodegenerative disorders, as well as additional synthetic tools that can be exploited to further explore T1AM-dependent mechanisms and the physiological roles of trace amine-associated receptor 1 (TAAR1)-mediated effects.

Excess Accumulation of Lipid Impairs Insulin Sensitivity in Skeletal Muscle

Both glucose and free fatty acids (FFAs) are used as fuel sources for energy production in a living organism. Compelling evidence supports a role for excess fatty acids synthesized in intramuscular space or dietary intermediates in the regulation of skeletal muscle function. Excess FFA and lipid droplets leads to intramuscular accumulation of lipid intermediates. The resulting downregulation of the insulin signaling cascade prevents the translocation of glucose transporter to the plasma membrane and glucose uptake into skeletal muscle, leading to metabolic disorders such as type 2 diabetes. The mechanisms underlining metabolic dysfunction in skeletal muscle include accumulation of intracellular lipid derivatives from elevated plasma FFAs. This paper provides a review of the molecular mechanisms underlying insulin-related signaling pathways after excess accumulation of lipids.

Alagebrium Mitigates Metabolic Insults in High Carbohydrate and High Fat Diet Fed Wistar Rats

Background: Metabolic syndrome (MS) is characterized by sustained hyperglycemia that triggers advanced glycation end products (AGEs) generation. Alagebrium (ALA) is an advanced glycation end products (AGEs) cross-links breaker.Methods: 32 Wistar rats were divided into normal control (NC) group (8 rats) and MS groups (24 rats) received a high carbohydrate high fat diet (HCFD) for 10 weeks. Rats with established MS were equally divided into 3 subgroups remained on HCFD for further 6 weeks: MS control (MSC), ALA treated received 10 mg/kg/day ALA orally and metformin treated (MF) (a reference drug) received 50 mg/kg/day MF orally. The studied parameters were systolic blood pressure (SBP), body and liver weights (BW, LW), LW/BW% ratio, fasting blood glucose (FBG), serum insulin, lipid profile, liver enzymes, serum AGEs, hepatic Interleukin-17 (IL-17), adipokines, pAkt/Akt ratio, and liver histopathology.Results: HCFD elevated SBP, BW, LW and LW/BW% ratio, FBG, serum insulin, and AGEs. It also deteriorated lipid profile and liver enzymes, induced inflammation, insulin resistance and histopathological derangements. ALA ameliorated the elevated SBP, FBG, lipid profile, liver enzymes, mitigated insulin resistance, hepatic IL-17, serum AGEs, modulated adipokines levels and improved liver histopathology. However, MF had better effects than ALA in all studied parameters except AGEs.Conclusion: ALA is protective against dietary-induced MS via ameliorating the inflammatory process and serum AGEs that implicated in MS pathogenesis, which makes it a promising new tool in MS treatment.

Ghrelin, resistin and insulin in obese diabetic women in Wad-Madani, Sudan

BACKGROUND

Obesity in the Sudan is increasing at alarming rate with the tendency of reaching an epidemic proportion in women. It is commonly associated with type 2 diabetes (T2D). Some adipokine hormones such as resistin are associated with obesity.

OBJECTIVES

To study how the levels of resistin, ghrelin and insulin are associated with obesity,fat distribution and (T2D) and to ascertain any interrelationships between them.

SUBJECTS AND METHODS

150 women, age ≥18 years old, resident in Wad-Madani town, Sudan were participated in the study. They were divided into 3 groups according to body mass index (BMI) value: I (normal weight), II (overweight) and III (obese diabetic). Fasting serum resistin and ghrelin concentrations were measured using ELISA method. Insulin levels were determined by radioimmunoassay(RIA).

RESULTS

The mean±SD levels of resistin 5.80±4.91ng/mL,Ghrelin107.60±26.67pg/M and Insulin 11.92±8.54mLU/ml in obese diabetic were found to be greater than in normal or overweight women. In normal weight values were 3.07±2.15 ng/mL 83.30±13.38pg/mL, and 6.62±6.77mLU/ml for resistini, ghrelin and Insulin, respectively. Values for overweight women 3.64±2.63 pg/mL 90±17.35 pg/mL and 8.13±7.54 mLU/ml for resistin, ghrelin and insulin respectively.

CONCLUSIONS AND RECOMMENDATIONS

Increased BMI, waist circumference (WC) and hormones (ghrelin and resistin) were associated with insulin resistance. Further studies are needed to accept or refute these findings.

Dietary supplement of Yunkang 10 green tea and treadmill exercise ameliorate high fat diet induced metabolic syndrome of C57BL/6 J mice

Background

Diet and exercise play important roles in ameliorating metabolic syndrome. Yunkang 10 (Camellia sinensis var. assamica) is a most cultivated tea variety for making tea in the Southwestern China. Currently, there is no report of healthy effects of Yunkang 10 green tea (YKGT) and treadmill exercise (Ex) on high fat diet induced metabolic syndrome (MetS). We aimed to investigate the beneficial effects and molecular mechanism of YKGT and Ex using high fat diet induced MetS of C57BL/6 mice.

Methods

Catechins and caffeine in water extract of YKGT were measured via high performance liquid chromatography (HPLC). 10-week old mice were fed with high fat diet (HFD) for 10 weeks to induce obese mice. Then the obese mice were fed with continuous high fat diet (HFD), HFD with YKGT, HFD with Ex, and HFD with both YKGT and Ex for 8 weeks, respectively. The another group of 10-week old mice fed with low fat diet (LFD) were used as control.

Results

HPLC data revealed that YKGT has abundantly high concentration of epigallocatechin gallate (EGCG) and caffeine compared to Longjing 43 (Camellia sinensis var. sinensis) green tea. YKGT and Ex significantly decreased the level of blood glucose, serum total cholesterol (TC), triglyceride (TG), insulin, and alanine aminotransferase activity (ALT) when compared to HFD group. The fatty liver and hepatic pro-inflammatory gene expression in the YKGT, Ex and YKGT+Ex groups was mitigated significantly compared with HFD group, respectively. The phosphorylation of inhibitor of nuclear factor kappa-B kinase α/β (IKKα/β) and inhibitor of nuclear factor kappa-B α (IkBα) protein in the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) signaling pathway was also decreased in YKGT or YKGT+Ex groups. The combination of YKGT and Ex prevented gene expression for lipid synthesis in the liver tissue, and significantly upregulated mRNA level of glucose transport genes in the skeletal muscles, when compared to the HFD group.

Conclusions

This study demonstrated that YKGT supplement or exercise appeared to reverse preexisting metabolic syndrome, and effectively relieved the fatty liver and hepatic inflammatory response induced by high fat diet. YKGT supplement and treadmill exercise together had better beneficial effects than only one intervention.