Relation of aging and sex hormones to metabolic syndrome and cardiovascular disease

Western diet-induced cognitive and metabolic dysfunctions in aged mice are prevented by rosmarinic acid in a sex-dependent fashion

BACKGROUND & AIMS

Unhealthy lifestyles, such as chronic consumption of a Western Diet (WD), have been associated with increased systemic inflammation and oxidative stress (OS), a condition that may favour cognitive dysfunctions during aging. Polyphenols, such as rosmarinic acid (RA) may buffer low-grade inflammation and OS, characterizing the aging brain that is sustained by WD, promoting healthspan. The aim of this study was to evaluate the ability of RA to prevent cognitive decline in a mouse model of WD-driven unhealthy aging and to gain knowledge on the specific molecular pathways modulated within the brain.

METHODS

Aged male and female C57Bl/6N mice were supplemented either with RA or vehicle for 6 weeks. Following 2 weeks on RA they started being administered either with WD or control diet (CD). Successively all mice were tested for cognitive abilities in the Morris water maze (MWM) and emotionality in the elevated plus maze (EPM). Glucose and lipid homeostasis were assessed in trunk blood while the hippocampus was dissected out for RNAseq transcriptomic analysis.

RESULTS

RA prevented insulin resistance in males while protecting both males and females from WD-dependent memory impairment. In the hippocampus, RA modulated OS pathways in males and immune- and sex hormones-related signalling cascades (Lhb and Lhcgr genes) in females. Moreover, RA overall resulted in an upregulation of Glp1r, recently identified as a promising target to prevent metabolic derangements. In addition, we also found an RA-dependent enrichment in nuclear transcription factors, such as NF-κB, GR and STAT3, that have been recently suggested to promote healthspan and longevity by modulating inflammatory and cell survival pathways.

CONCLUSIONS

Oral RA supplementation may promote brain and metabolic plasticity during aging through antioxidant and immune-modulating properties possibly affecting the post-reproductive hormonal milieu in a sex-dependent fashion. Thus, its supplementation should be considered in the context of precision medicine as a possible strategy to preserve cognitive functions and to counteract metabolic derangements.

In the land of not-unhappiness: On the state-of-the-art of targeting aging and age-related diseases by biomedical research

The concept of the Land of Not-Unhappiness refers to the potential achievement of eliminating the pathologies of the aging process. To inform of how close we are to settling in the land, we summarize and review the achievements of research on anti-aging interventions over the last hundred years with a specific focus on strategies that slow down metabolism, compensate for aging-related losses, and target a broad range of age-related diseases. We critically evaluate the existing interventions labeled as "anti-aging," such as calorie restriction, exercise, stem cell administration, and senolytics, to provide a down-to-earth evaluation of their current applicability in counteracting aging. Throughout the text, we have maintained a light tone to make it accessible to non-experts in biogerontology, and provide a broad overview for those considering conducting studies, research, or seeking to understand the scientific basis of anti-aging medicine.

Impact of Secondary Amenorrhea on Cardiovascular Disease Risk in Physically Active Women: A Systematic Review and Meta-Analysis

BACKGROUND

Exercise-associated secondary amenorrhea results in estrogen deficiency, which may lead to dysfunction in estrogen's normal cardioprotective pathways. Estrogen may be essential in a woman's endothelial adaptations to exercise. The objective of this review was to assess the association between secondary amenorrhea in physically active women and cardiovascular disease (CVD) risk.

METHODS AND RESULTS

A literature search was performed in January 2023 and updated in August 2023 of the Cumulative Index to Nursing and Allied Health Literature (EBSCOhost), Cochrane Library, Embase (Ovid), MEDLINE (Ovid), SPORTDiscus (EBSCOhost), and Scopus from inception to present with no date or language limitations. Citation chaining was done to screen for additional studies. Eight sources were searched for gray literature. Studies that compared physically active women with amenorrhea to physically active women with eumenorrhea aged 18 to 35 years with evidence of CVD, alterations to cardiovascular physiology, or CVD risks were included. Eighteen observational studies from 3 countries were included. Overall, the quality of evidence was good. A meta-analysis was performed. Physically active women with secondary amenorrhea had significantly lower estradiol, flow-mediated dilation, resting heart rate, systolic blood pressure, and diastolic blood pressure and higher total cholesterol, triglycerides, high-density lipoprotein, and low-density lipoprotein cholesterol.

CONCLUSIONS

Estrogen deficiency resulting from exercise-associated secondary amenorrhea in physically active women may impact cardiovascular physiology and certain CVD risk factors. The research in this area is observational; therefore, findings should be interpreted cautiously. However, as exercise-associated secondary amenorrhea is reversible and the primary prevention of CVD is important for public health, it may be important to treat secondary amenorrhea and restore estrogen levels.

Impact of secondary amenorrhea on cardiovascular disease risk in physically active women: a systematic review protocol

OBJECTIVE

The objective of this review is to assess the association between secondary amenorrhea in physically active women and cardiovascular disease risk.

INTRODUCTION

It is well established that a woman's risk of cardiovascular disease greatly increases after menopause. The sharp decline in estrogen is seen as a causal factor. Exercise-induced secondary amenorrhea results in estrogen deficiency, which may lead to dysfunction in estrogen's cardioprotective pathways. Further, estrogen may be essential in a woman's endothelial adaptations to exercise. The impact of secondary amenorrhea on cardiovascular disease risk in premenopausal women is not well established.

INCLUSION CRITERIA

This review will consider studies that include physically active women experiencing amenorrhea in any country. Only studies that present evidence of cardiovascular disease, alterations to cardiovascular physiology, or data on cardiovascular risk factors (eg, lipid profile changes) will be considered. The review will consider experimental or observational epidemiological study designs.

METHODS

Searches will be conducted in CINAHL (EBSCOhost), the Cochrane Library, Embase (Ovid), MEDLINE (Ovid), SPORTDiscus (EBSCOhost), and Scopus from inception to present with no date or language limitations. Two independent reviewers will screen titles, abstracts, and full texts, appraise methodological quality, and extract data from studies. Where possible, studies will be pooled in a statistical meta-analysis in addition to subgroup analyses. Where pooling is not possible, the findings will be presented in narrative format. Certainty of the evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

REVIEW REGISTRATION

PROSPERO CRD42023360781.

The effect of flaxseed supplementation on sex hormone profile in adults: a systematic review and meta-analysis

Inconsistent data suggest that flaxseed supplementation may have a role in sex hormones. We aimed to carry out a systematic review and meta-analysis of randomized controlled trials (RCTs) investigating effects of flaxseed supplementation on sex hormone profile. PubMed, Scopus, Embase, Cochrane Library, Web of Science databases, and Google Scholar were searched up to March 2023. Standardized mean difference (SMD) was pooled using a random-effects model. Sensitivity analysis, heterogeneity, and publication bias were reported using standard methods. The quality of each study was evaluated with the revised Cochrane risk-of-bias tool for randomized trials, known as RoB 2. Finding from ten RCTs revealed that flaxseed supplementation had no significant alteration in follicle-stimulating hormone (FSH) (SMD: -0.11; 95% CI: -0.87, 0.66: p = 0.783), sex hormone-binding globulin (SHBG) (SMD: 0.35; 95% CI: -0.02, 0.72; p = 0.063), total testosterone (TT) levels (SMD: 0.17; 95% CI: -0.07, 0.41; p = 0.165), free androgen index (FAI) (SMD = 0.11, 95% CI: -0.61, 0.83; p = 0.759), and dehydroepiandrosterone sulfate (DHEAS) (SMD: 0.08, 95%CI: -0.55, 0.72, p = 0.794). Flaxseed supplementation had no significant effect on sex hormones in adults. Nevertheless, due to the limited included trials, this topic is still open and needs further studies in future RCTs.

Putative causal inference for the relationship between obesity and sex hormones in males: a bidirectional Mendelian randomization study

Background

Obesity is a chronic disease with a high prevalence rate and is an established risk factor for human health. Body mass index (BMI) is a common and primary indicator used in assessing obesity. This work aims to investigate the putative causal relationship among BMI, sex hormone-binding globulin (SHBG), bioavailable testosterone (BioT), and estradiol levels.

Materials and Methods

We conducted a bidirectional Mendelian randomization study, using single-nucleotide polymorphisms (SNPs) strongly associated with BMI, SHBG, BioT, and estradiol as instrumental variables. All SNPs were identified from the genome-wide association study (GWAS) summary data of large sample studies recruiting more than 150,000 European adult male individuals. The inverse-variance-weighted (IVW) approach was used as a primary algorithm for putative causal estimation.

Results

Genetically predicted elevated BMI was associated with decreased SHBG (IVW, β = -0.103, 95% confidence interval [CI] [-0.113 to -0.092], P = 1.50 × 10^-77) and BioT levels (IVW, β = -0.139, 95% CI [-0.165 to -0.113], P = 9.54 × 10^-26) and high estradiol levels (IVW, β = 0.014, 95% CI [0.009-0.019], P = 2.19 × 10^-7). Increased SHBG levels were causally associated with low BMI (IVW, β = -0.051, 95% CI [-0.098 to -0.005], P = 0.030) and BioT (IVW, β = -0.126, 95% CI [-0.175 to -0.077], P = 5.97 × 10^-7) and high estradiol levels (IVW, β = 0.046, 95% CI [0.035-0.056], P = 6.51 × 10^-17). Conversely, no evidence of an effect of estradiol imbalance on SHBG levels (IVW, β = 1.035, 95% CI [-0.854 to 2.926], P = 0.283) and BMI (IVW, β = 0.091, 95% CI [-0.094 to 0.276], P = 0.336) was obtained. However, increased BioT levels were causally associated with lower SHBG levels (IVW, β = -0.044, 95% CI [-0.061 to -0.026], P = 8.76 × 10^-7), not BMI (IVW, β = -0.006, 95% CI [-0.035 to 0.023], P = 0.679).

Conclusions

The findings support a network putative causal relationship among BMI, SHBG, BioT, and estradiol. SHBG, BioT, and estradiol may partly mediate the effect of obesity on male health. Reasonably modulating BioT and estradiol, especially SHBG, facilitated the attenuation of the harmful effects of obesity on male health.

Greater Ecologically Assessed Positive Experiences Predict Heightened Sex Hormone Concentrations Across Two Weeks in Older Adults

OBJECTIVES

Sex hormones are important components of healthy aging, with beneficial effects on physical and mental health. Positive experiences such as elevated mood, lowered stress, and higher well-being also contribute to health outcomes and, in younger adults, may be associated with elevated sex hormone levels. However, little is known about the association between positive experiences and sex hormones in older adults.

METHODS

In this study, older men and women (N = 224, 70+ years of age) provided blood samples before and after a 2-week period of ecological momentary assessment (EMA) of positive and negative experiences (assessed based on self-reporting items related to affect, stress, and well-being). Concentrations of a panel of steroid sex hormones and glucocorticoids were determined in blood.

RESULTS

Higher levels of positive experiences reported in daily life across 2 weeks were associated with increases in free (biologically active) levels of testosterone (B = 0.353 [0.106, 0.601], t(221.3) = 2.801, p = .006), estradiol (B = 0.373 [0.097, 0.649], t(225.1) = 2.645, p = .009), and estrone (B = 0.468 [0.208, 0.727], t(224.3) = 3.535, p < .001) between the start and the end of the 2-week EMA period.

DISCUSSION

These findings suggest that sex hormones may be a pathway linking positive experiences to health in older adults.

Sex differences in pharmacological interventions and their effects on lifespan and healthspan outcomes: a systematic review

With an increasing aging population, the burden of age-related diseases magnifies. To alleviate this burden, geroprotection has been an area of intense research focus with the development of pharmacological interventions that target lifespan and/or healthspan. However, there are often sex differences, with compounds mostly tested in male animals. Given the importance of considering both sexes in preclinical research, this neglects potential benefits for the female population, as interventions tested in both sexes often show clear sexual dimorphisms in their biological responses. To further understand the prevalence of sex differences in pharmacological geroprotective intervention studies, we performed a systematic review of the literature according to the PRISMA guidelines. Seventy-two studies met our inclusion criteria and were classified into one of five subclasses: FDA-repurposed drugs, novel small molecules, probiotics, traditional Chinese medicine, and antioxidants, vitamins, or other dietary supplements. Interventions were analyzed for their effects on median and maximal lifespan and healthspan markers, including frailty, muscle function and coordination, cognitive function and learning, metabolism, and cancer. With our systematic review, we found that twenty-two out of sixty-four compounds tested were able to prolong both lifespan and healthspan measures. Focusing on the use of female and male mice, and on comparing their outcomes, we found that 40% of studies only used male mice or did not clarify the sex. Notably, of the 36% of pharmacologic interventions that did use both male and female mice, 73% of these studies showed sex-specific outcomes on healthspan and/or lifespan. These data highlight the importance of studying both sexes in the search for geroprotectors, as the biology of aging is not the same in male and female mice. Systematic Review Registration: [website], identifier [registration number].

Machine Learning Approach for Metabolic Syndrome Diagnosis Using Explainable Data-Augmentation-Based Classification

Metabolic syndrome (MetS) is a cluster of risk factors including hypertension, hyperglycemia, dyslipidemia, and abdominal obesity. Metabolism-related risk factors include diabetes and heart disease. MetS is also linked to numerous cancers and chronic kidney disease. All of these variables raise medical costs. Developing a prediction model that can quickly identify persons at high risk of MetS and offer them a treatment plan is crucial. Early prediction of metabolic syndrome will highly impact the quality of life of patients as it gives them a chance for making a change to the bad habit and preventing a serious illness in the future. In this paper, we aimed to assess the performance of various algorithms of machine learning in order to decrease the cost of predictive diagnoses of metabolic syndrome. We employed ten machine learning algorithms along with different metaheuristics for feature selection. Moreover, we examined the effects of data augmentation in the prediction accuracy. The statistics show that the augmentation of data after applying feature selection on the data highly improves the performance of the classifiers.

Prevalence of the metabolic syndrome and associated factors among inpatients with severe mental illness in Botswana: a cross-sectional study

INTRODUCTION

The metabolic syndrome, a cluster of inter-related risk factors for cardiovascular diseases is highly prevalent among individuals with obesity and sedentary lifestyle. Chronic psychiatric disorders such as severe mental illness are associated with increased risk for cardiovascular diseases. We aimed to assess the prevalence and correlates of metabolic syndrome among inpatients with severe mental illness in a resource limited setting with high HIV prevalence.

METHODS

This was a cross-sectional study among adult inpatients at a referral psychiatric hospital in Botswana. We used convenience sampling to enrol participants available at the time of the study. The National Cholesterol Education Program Adult Treatment Panel-III (NCEP-ATP III) criteria was used to define the metabolic syndrome. Data were analysed using descriptive statistics as well as multiple logistic regression modelling.

RESULTS

A total of 137 participants were enrolled. Of these, 119 (87%) had complete data for the main analysis. The overall prevalence of metabolic syndrome was 22.6% (95% CI 15.9, 30.6) and did not differ significantly by gender or HIV status. Age was significantly associated with the risk of having the metabolic syndrome while gender, body mass index, HIV status, and days of moderate physical activity were not.

CONCLUSION

There was a moderately high prevalence of metabolic syndrome. Thus, the management of individuals with severe mental illness in resource limited settings should include assessment of cardiovascular risk and target modifiable risk factors in this population. Consideration for the patient's age should be made when rationalizing the limited resources available for assessing metabolic syndrome among patients with severe mental illness.

The Roles of Androgens in Humans: Biology, Metabolic Regulation and Health

Androgens are an important and diverse group of steroid hormone molecular species. They play varied functional roles, such as the control of metabolic energy fate and partition, the maintenance of skeletal and body protein and integrity and the development of brain capabilities and behavioral setup (including those factors defining maleness). In addition, androgens are the precursors of estrogens, with which they share an extensive control of the reproductive mechanisms (in both sexes). In this review, the types of androgens, their functions and signaling are tabulated and described, including some less-known functions. The close interrelationship between corticosteroids and androgens is also analyzed, centered in the adrenal cortex, together with the main feedback control systems of the hypothalamic-hypophysis-gonads axis, and its modulation by the metabolic environment, sex, age and health. Testosterone (T) is singled out because of its high synthesis rate and turnover, but also because age-related hypogonadism is a key signal for the biologically planned early obsolescence of men, and the delayed onset of a faster rate of functional losses in women after menopause. The close collaboration of T with estradiol (E2) active in the maintenance of body metabolic systems is also presented Their parallel insufficiency has been directly related to the ravages of senescence and the metabolic syndrome constellation of disorders. The clinical use of T to correct hypoandrogenism helps maintain the functionality of core metabolism, limiting excess fat deposition, sarcopenia and cognoscitive frailty (part of these effects are due to the E2 generated from T). The effectiveness of using lipophilic T esters for T replacement treatments is analyzed in depth, and the main problems derived from their application are discussed.

Thyroid Function and Metabolic Syndrome in Children and Adolescents with Neuromotor Disability

Thyroid function plays a crucial role in nervous system integrity and metabolic homeostasis. We evaluated the pattern of TSH, FT4 and FT3 release in children with neuromotor impairment (NI) in relationship with metabolic syndrome (MS). We enrolled 55 patients with NI and 30 controls. Clinical parameters, thyroid function and MS presence were recorded. Principal component analysis (PCA), cluster analysis, and logistic regression models were performed. MS was detected in 54.5% of patients. Four clusters were identified: the first one included only controls and, contrasting with cluster 4, was exclusively characterized by children with disability and MS. This latter showed increased FT4 and FT3 and decreased TSH levels. Cluster 2, characterized by disability without MS showed high FT4 and FT3, whereas cluster 3 with low FT4 and FT3 mainly included disability (90%) and showed prevalent MS (57%). The association between TSH and NI is represented by a U-shape structure. The TSH, FT3 and FT4 release patterns may reflect thyrotropic adaptation, allostatic response and compensatory mechanisms. These mechanisms, found in both MS and disability, show that the odds of having a condition of NI with or without MS increase as the TSH values deviate, in both directions, from a value of 2.5 mLU/mL.

Endogenous sex hormones homeostasis disruption combined with exogenous phthalates exposure increase the risks of childhood high blood pressure: A cohort study in China

BACKGROUND

The structural similarity between sex hormones and exogenous phthalates (PAEs) enabled them as disrupters in regulating childhood blood pressure (BP). We aim to explore the association of sex hormones homeostasis and PAEs metabolites with childhood high BP (HBP).

METHODS

A cohort study was conducted with 1416 children aged 7-13 years at baseline and with 824, 819, and 801 children completing three waves' follow up. Serum testosterone (TT) and estradiol (E2) in children during three consecutive waves of surveys were measured by radioimmunoassay, and then TT/E2 ratio calculated as TT divided by E2 were used to represent sex hormones homeostasis. Seven urinary PAEs metabolites were measured in children of first wave. The BP Z-Scores and HBP across waves were obtained by sex, age, and height specific percentiles. Log-binomial regression models with adjusted risk ratios (aRR) after adjusting for confounders were utilized.

RESULTS

The prevalence of HBP at the baseline survey was 25.5%, and increased from 26.3% in the first wave of survey to 35.0% in the third wave of survey. PAEs were negatively correlated with E2, while positively correlated with TT and TT/E2 ratio. A positive association of the serum TT levels, TT/E2 ratio, and total PAEs was found with HBP prevalence (in wave 1, 2 and 3 with TT (aRR): 1.63, 1.37 and 1.45; with TT/E2: 1.63, 1.42 and 1.20; with PAEs: 1.40, 1.32 and 1.32), persistent HBP (with TT (aRR): 2.19; TT/E2: 2.16; PAEs: 2.57), occasional HBP (with TT (aRR): 1.94; TT/E2: 1.72; PAEs: 1.38), and new HBP incidence (with TT (aRR): 1.44; TT/E2: 1.57; PAEs: 1.67), but E2 had a negative association with HBP phenotypes (HBP prevalence in wave 1, 2 and 3 (aRR): 0.77, 0.93, and 1.10; persistent HBP: 0.47; occasional HBP: 0.96; new HBP incidence: 0.81). The E2 and PAEs had antagonistic effects on HBP risks in children, particularly in girls and those with high BMI group, but the TT levels, TT/E2 ratio and PAEs had synergistic effects on HBP risks in children, particularly in boys and those with high BMI group.

CONCLUSION

Exogenous PAEs exposure and endogenous sex hormones homeostasis disruption independently increase the risks of HBP. Moreover, the exogenous PAEs exposure could disrupt the endogenous sex hormones homeostasis in children, thereby combinedly increased risks of childhood HBP.

The Deficiency of SCARB2/LIMP-2 Impairs Metabolism via Disrupted mTORC1-Dependent Mitochondrial OXPHOS

Deficiency in scavenger receptor class B, member 2 (SCARB2) is related to both Gaucher disease (GD) and Parkinson’s disease (PD), which are both neurodegenerative-related diseases without cure. Although both diseases lead to weight loss, which affects the quality of life and the progress of diseases, the underlying molecular mechanism is still unclear. In this study, we found that Scarb2^−/− mice showed significantly reduced lipid storage in white fat tissues (WAT) compared to WT mice on a regular chow diet. However, the phenotype is independent of heat production, activity, food intake or energy absorption. Furthermore, adipocyte differentiation and cholesterol homeostasis were unaffected. We found that the impaired lipid accumulation of Adiponectin-cre; Scarb2^fl/fl mice was due to the imbalance between glycolysis and oxidative phosphorylation (OXPHOS). Mechanistically, the mechanistic target of rapamycin complex 1 (mTORC1)/ eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1) pathway was down-regulated in Scarb2 deficient adipocytes, leading to impaired mitochondrial respiration and enhanced glycolysis. Altogether, we reveal the role of SCARB2 in metabolism regulation besides the nervous system, which provides a theoretical basis for weight loss treatment of patients with neurodegenerative diseases.

Temporal patterns of alterations in obesity index, lipid profile, renal function and blood pressure during the development of hypertension in male, but not female, rats fed a moderately high-fat diet

CONTEXT

Male Sprague-Dawley rats consuming a moderately high-fat (MHF)-diet diverge into obesity-prone (OP) with hypertension and obesity-resistant.

OBJECTIVES

To study the temporal inter-relationships between body-weight, obesity-index, plasma lipid-profile, renal functional parameters and systolic-pressure alterations during 10-weeks feeding MHF or normal diet to male and female rats.

METHODS

Body-weight, obesity-index and systolic-pressure were measured weekly, while metabolic-cage and blood-sampling protocols were performed every other week. After 10-weeks, renal excretory responses to acute salt-loading and renal autoregulation were examined.

RESULTS

The male-OP group had progressively increased body-weight, plasma-triglyceride and systolic-pressure from Weeks 2, 4 and 5, respectively, lower renal sodium-excretion at weeks 4-8 and finally, delayed excretory response to salt-loading and rightward and downward shifts in renal autoregulatory curves compared to all other groups.

CONCLUSION

Feeding the MHF-diet in male-OP rats led to a greater weight-gain and adiposity followed by the development of atherogenic-hyperlipidaemia and persistently impaired pressure-natriuresis to induce hypertension.

Integration of the Human Gut Microbiome and Serum Metabolome Reveals Novel Biological Factors Involved in the Regulation of Bone Mineral Density

While the gut microbiome has been reported to play a role in bone metabolism, the individual species and underlying functional mechanisms have not yet been characterized. We conducted a systematic multi-omics analysis using paired metagenomic and untargeted serum metabolomic profiles from a large sample of 499 peri- and early post-menopausal women to identify the potential crosstalk between these biological factors which may be involved in the regulation of bone mineral density (BMD). Single omics association analyses identified 22 bacteria species and 17 serum metabolites for putative association with BMD. Among the identified bacteria, Bacteroidetes and Fusobacteria were negatively associated, while Firmicutes were positively associated. Several of the identified serum metabolites including 3-phenylpropanoic acid, mainly derived from dietary polyphenols, and glycolithocholic acid, a secondary bile acid, are metabolic byproducts of the microbiota. We further conducted a supervised integrative feature selection with respect to BMD and constructed the inter-omics partial correlation network. Although still requiring replication and validation in future studies, the findings from this exploratory analysis provide novel insights into the interrelationships between the gut microbiome and serum metabolome that may potentially play a role in skeletal remodeling processes.

Endoplasmic Reticulum Stress and miRNA Impairment in Aging and Age-Related Diseases

Aging is a physiological process defined by decreased cellular and tissue functions. Reduced capacity of protein degradation is one of the important hallmarks of aging that may lead to misfolded protein accumulation and progressive loss of function in organ systems. Recognition of unfolded/misfolded protein aggregates via endoplasmic reticulum (ER) stress sensors activates an adaptive mechanism, the unfolded protein response (UPR). The initial step of UPR is defined by chaperone enhancement, ribosomal translation suppression, and misfolded protein degradation, while prolonged ER stress triggers apoptosis. MicroRNAs (miRNAs) are non-coding RNAs affecting various signaling pathways through degradation or translational inhibition of targeted mRNAs. Therefore, UPR and miRNA impairment in aging and age-related diseases is implicated in various studies. This review will highlight the recent insights in ER stress–miRNAs alterations during aging and age-related diseases, including metabolic, cardiovascular, and neurodegenerative diseases and several cancers.

Incidence and long-term specific mortality trends of metabolic syndrome in the United States

PURPOSE

Metabolic syndrome (MetS) is extremely prevalent and related to severe diseases and death. This study aims to investigate the incidence and mortality trends among MetS over the past few decades. The gender and age differences of MetS are also explored.

PATIENTS AND METHODS

Adults with MetS were screened in the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2014. The mortality data were also acquired. Then we assessed the incidence and mortality trends of MetS in the United States.

RESULTS

Our study included 14171 participants with a mean age of 46.8 ± 19.3 years, of whom 7354 (51.9%) were women. Among them, 4789 participants were subsequently diagnosed with MetS. From 1999 to 2014, the overall trend of MetS incidence increased (from 27.6 to 32.3%; adjusted odds ratios [aOR], 1.71; 95% confidence interval [CI], 1.42-2.05; P-value <0.001, P for trend <0.001). In more detail, the incidence of MetS rose first but subsequently plateaued and declined. Obvious downward trends were observed from 29.6 to 2.7% for all-cause mortality (aOR, 0.12; 95%CI, 0.07-0.21; P-value <0.001, P for trend <0.001) and 4.8 to 0.8% for cardio-cerebrovascular mortality (aOR, 0.17; 95%CI, 0.05-0.61; P-value =0.007, P for trend <0.001). All-cause mortality decreased yearly, whereas cardio-cerebrovascular death increased briefly before declining and stabilizing. Similarly, the temporal mortality trends in MetS patients of different ages and genders had the same results. Specifically, the incidence of MetS was higher in women than in men (adjusted P =0.003; OR, 1.14; 95%CI, 1.05-1.24), but the mortality was significantly lower after an average of 7.7 years of follow-up (all-cause mortality, adjusted P <0.001; hazard ratio [HR], 0.68; 95%CI, 0.57-0.81; cardio-cerebrovascular mortality, adjusted P =0.004; HR, 0.55; 95%CI, 0.37-0.83).

CONCLUSION

From 1999 to 2014, the incidence of MetS in U.S. adults significantly increased overall, while the mortality rate of MetS had a considerable downward trend. Both trends showed marked gender differences, being more prevalent and at lower risk in women compared with men. It is important to identify the factors that will curb the incidence of MetS and decrease mortality, especially in male patients.

Are dentists more prone to metabolic syndrome and occupational stress?

OBJECTIVE

The aim of this study was to investigate the prevalence of metabolic syndrome (MS) among dentists in Riyadh, Saudi Arabia. The study also explored the causes of occupational stress among the participating dentists.

MATERIALS & METHODS

The participants included a conveniently selected sample of dentists (N = 126; Males = 65; Females = 61). The participants' anthropometric measurements/blood sample analysis were carried out and they completed a self-administered questionnaire. Data analysis included demographics, gender/age wise comparison using SPSS (p < 0.05). For the diagnosis of MS, updated criteria of the National Cholesterol Education Program was applied.

RESULTS

Participants diagnosed with MS were 13 (10.3%), Males = 11(8.7%) and Females = 2(1.5%). Physical activity of 6 (15.8%) with MS was only 0-2 hours/week. 9 (14.5%) participants with MS declared positive family history for MS. The average systolic (117.55±11.33) and diastolic blood pressure (71.9±9.34) of the participants was found to be normal with no gender wise statistical difference. No gender wise statistical differences (p > 0.05) were observed for cholesterol, triglycerides and HDL. However, significant difference (p = 0.00) was found for the fasting glucose level (Males = 5.69±1.49; Females = 4.94±0.42). Overall mean scoring (3.00±1.11) for the stress showed that the participants fall into the average/moderate level of stress category (Males = 3.16±1.02; Females = 2.83±1.08). Almost two third (68.26%) of the participant's responded that they were under some kind of stress.

CONCLUSIONS

MS was found to be less frequent among the dentists working in the city of Riyadh. Overall, the dentists were under moderate level of occupational stress, with male dentists being more prone to work related stress.

White adipose tissue dysfunction in obesity and aging

Both obesity and aging are associated with the development of metabolic diseases such as type 2 diabetes and cardiovascular disease. Chronic low-grade inflammation of adipose tissue is one of the mechanisms implicated in the progression of these diseases. Obesity and aging trigger adipose tissue alterations that ultimately lead to a pro-inflammatory phenotype of the adipose tissue-resident immune cells. Obesity and aging also share other features such as a higher visceral vs. subcutaneous adipose tissue ratio and a decreased lifespan. Here, we review the common characteristics of obesity and aging and the alterations in white adipose tissue and resident immune cells. We focus on the adipose tissue metabolic derangements in obesity and aging such as inflammation and adipose tissue remodeling.

Cardiac, Macro-, and Micro-Circulatory Abnormalities in Association With Individual Metabolic Syndrome Component: The Northern Shanghai Study

Objective: This study investigated the association of metabolic syndrome (MS) and its components with cardiac, macro-, and micro-circulatory abnormalities in an elderly Chinese population.

Methods: This cross-sectional study was conducted using data for 1,958 participants from the Northern Shanghai Study aged over 65 years without a history of cardiovascular disease. MS was defined according to the National Cholesterol Education Program Adult Treatment Panel III in 2005 (NCEPIII 2005). Asymptomatic cardiovascular impairment parameters, including the left ventricle mass index (LVMI), peak transmitral pulsed Doppler velocity/early diastolic tissue Doppler velocity (E/Ea), carotid-femoral pulse wave velocity (cf-PWV), ankle-brachial index (ABI), carotid intima-media thickness (CIMT), arterial plaque, and urinary albumin–creatinine rate (UACR), were evaluated.

Results: LVMI, E/Ea, cf-PWV, and the proportion of UACR > 30 mg/g exhibited increasing trends while ABI exhibited a decreasing trend according to the number of MS components (all p for trend < 0.01). Logistic regression analysis revealed that MS was significantly associated with LV hypertrophy (LVH), LV diastolic dysfunction, arteriosclerosis, and microalbuminuria (all p < 0.001). Central obesity and high blood pressure were associated with all cardiovascular abnormalities (all p < 0.05), whereas elevated plasma glucose was associated with arteriosclerosis and microalbuminuria (both p < 0.001). In addition, high triglyceride levels were associated with microalbuminuria (p < 0.05).

Conclusions: MS is significantly associated with cardiac, macro-, and micro-circulatory abnormalities in elderly Chinese. Moreover, the presence of individual MS components may have specific prognostic significance.

Regular physical activity reduces the proinflammatory response in older women with diabetes and hypertension in the postmenopausal phase

Aging in women is characterized by extreme hormonal changes leading them to develop a chronic low-grade inflammation that is linked to the development of systemic arterial hypertension (SAH) and type 2 diabetes mellitus (T2DM). In this scenario, physical activity emerges as an interesting methodology, since it seems to be connected to a decrease in serum levels of some pro-inflammatory cytokines. Nevertheless, most studies evaluate these cytokines in an isolated manner not considering the influence of comorbidities on the responsiveness of participants to the benefits of physical activity. So, this study aimed to assess the influence of physical activity on body composition, anthropometric parameters, lipid profile, and inflammatory markers of diabetic and hypertensive older postmenopausal women. We evaluated 163 women aged from 60 to 80 years, diagnosed with T2DM and SAH that were assisted by the Family Health Units in Vitória da Conquista, Bahia, Brazil. The pratice of physical activity was measured by the International Physical Activity Questionnaire with the participants being classified as active or sedentary individuals. Active older women presented better body composition, lipid profile and inflammatory balance. This was connected to a better correlation profile between these factors in active older women, characteristics that were not noticed in sedentary older women. Moreover, IL-17A and the relationship between IL-10 and the other pro-inflammatory cytokines examined was greatly influenced by physical activity. Consequently, physical activity is linked to a global improvement in T2DM and SAH risk factors and with a positive inflammatory modulation in diabetic and hypertensive older women.

Index of Cardiac Age Index and Cardiometabolic Biomarkers in Adults with Metabolic Syndrome

Background: The presence of metabolic syndrome (MetS) seems to alter or accelerate the aging process of tissues or organs including the heart. We aim to investigate whether MetS are associated with an index of cardiac age calculated by parameters derived from 128-slice cardiac multidetector computed tomography (MDCT) and cardiometabolic biomarkers in adults. Materials and Methods: In this cross-sectional study, the data were collected from 135 subjects who underwent a comprehensive health checkup, including cardiac MDCT in adults (age ≥18 years). Cardiometabolic biomarkers and an index of cardiac age were measured. Results: Sixty-one (45.2%) had MetS and 44 subjects (32.6%) presented with moderate or severe coronary artery stenosis (CAS) on cardiac MDCT. MetS had positive correlations with several anthropometric variables, metabolic variables [triglyceride, gamma-glutamyl transpeptidase (GGT), homeostatic model assessment of insulin resistance (HOMA-IR)], and systolic blood pressure, cardiac parameters, an index of cardiac age and CAS, whereas had a negative correlation with high-density lipoprotein cholesterol. The diagnostic accuracy for MetS had similar area under the curve among the four variables (index of cardiac age, CAS, HOMA-IR, GGT). On age-adjusted multivariate analysis, only high index of cardiac age (≥55.0 years), and high HOMA-IR (≥1.22) were significantly and independently associated with MetS [odds ratio (OR) 2.48, 95% confidence interval (CI) 1.19-5.18, P = 0.016 and OR 3.41, 95% CI 1.65-7.06, P = 0.001, respectively]. Conclusion: Adults with MetS had higher index of cardiac age and higher HOMA-IR, compared with adults without MetS.

Hormonal and Metabolic Changes of Aging and the Influence of Lifestyle Modifications

Increased life expectancy combined with the aging baby boomer generation has resulted in an unprecedented global expansion of the elderly population. The growing population of older adults and increased rate of age-related chronic illness has caused a substantial socioeconomic burden. The gradual and progressive age-related decline in hormone production and action has a detrimental impact on human health by increasing risk for chronic disease and reducing life span. This article reviews the age-related decline in hormone production, as well as age-related biochemical and body composition changes that reduce the bioavailability and actions of some hormones. The impact of hormonal changes on various chronic conditions including frailty, diabetes, cardiovascular disease, and dementia are also discussed. Hormone replacement therapy has been attempted in many clinical trials to reverse and/or prevent the hormonal decline in aging to combat the progression of age-related diseases. Unfortunately, hormone replacement therapy is not a panacea, as it often results in various adverse events that outweigh its potential health benefits. Therefore, except in some specific individual cases, hormone replacement is not recommended. Rather, positive lifestyle modifications such as regular aerobic and resistance exercise programs and/or healthy calorically restricted diet can favorably affect endocrine and metabolic functions and act as countermeasures to various age-related diseases. We provide a critical review of the available data and offer recommendations that hopefully will form the groundwork for physicians/scientists to develop and optimize new endocrine-targeted therapies and lifestyle modifications that can better address age-related decline in heath.

The Relationship Between Thyroid Function and Metabolic Syndrome and Its Components: A Cross-Sectional Study in a Chinese Population

OBJECTIVE

The present study examined the relationship between thyroid function status and the prevalence of metabolic syndrome in a Chinese population.

METHODS

Cross-sectional data were obtained from the Thyroid Disease, Iodine Nutrition and Diabetes Epidemiology (TIDE) Survey. A total of 62,408 subjects aged ≥18 years were enrolled. Differences in metabolic indicators and the prevalence of metabolic syndrome according to sex and thyroid function status were compared. Logistic regression was used to analyze the influence of thyroid function on metabolic syndrome and its components.

RESULTS

The prevalence of metabolic syndrome was generally higher in men than women. Overt hyperthyroidism and subclinical hypothyroidism had a significant effect on metabolism in men. Body mass index (BMI), waist circumference, and triglycerides (TGs) were significantly lower in men in the overt hyperthyroidism group, and BMI, waist circumference, systolic blood pressure (SBP) and TGs were higher in men in the subclinical hypothyroidism group than men in the normal group. Overt and subclinical hypothyroidism had significant impacts on metabolic components in women. BMI, waist circumference, TGs, SBP and DBP in the subclinical and overt hypothyroidism groups were significantly higher than the euthyroid group in women. The relative risk of abdominal obesity and hypertriglyceridemia was increased in women with hypothyroidism. Thyroid dysfunction had different effects on metabolic syndrome and its components before and after menopause.

CONCLUSION

Thyroid function had important effects on the prevalence of metabolic syndrome. Women with hypothyroidism, especially post-menopausal women, had a higher risk of metabolic syndrome than men.

Reference intervals for routine biochemical markers and body mass index: A study based on healthcare center database in northeastern Iran

Age- and sex-specific reference intervals (RIs) for some biochemical tests may be useful for their interpretation, due to the variations in lifestyle and genetic, or ethnic factors. The aim of this study was to obtain RIs for some routine biochemical markers including a serum lipid profile, fasting blood glucose (FBG), aspartate and alanine aminotransferase (AST and ALT), uric acid, and body mass index (BMI) in subjects who attended primary healthcare centers. The large database of primary healthcare centers uses RIs to report results for children, adolescents, and young and old adults. RIs were obtained by using the indirect method, recommended by the CLSI Ep28-A3 guidelines. RIs for FBG, BMI, and serum lipid profile, including triglyceride, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol in people aged 18 to 120 years, were obtained without age/sex segmentation. RIs for serum AST, ALT, and uric acid were obtained without age segmentation, though these RIs were higher in males than females. The RIs for AST, ALT, and uric acid were higher in men, while the RIs for the other variables were similar in both sexes. This is the first study reporting the use of indirect RIs for BMI.

Impact of different fructose concentrations on metabolic and behavioral parameters of male and female mice

Clinical evidence has shown that a high consumption of sugar-sweetened beverages is a risk factor for developing obesity and metabolic syndrome. There has also been increasing interest in the potential effects of high-fructose intake on behavior. The present study evaluated sex differences in behavioral and metabolic characteristics in response to chronic fructose intake in mice. Swiss mice (3-months-old) had access to tap water or fructose-water solution (at 15% or 30% w/v) ad libitum for nine weeks. After the 8 weeks, the mice were submitted to a battery of behavioral tests. A glucose tolerance test was performed one day after these behavioral tests, and the next day blood was collected for biochemical analysis. At a 15% concentration, fructose-intaking resulted in higher plasma cholesterol levels and glucose intolerance in mice that paralleled with a passive stress-coping behavior in the female mice and lower self-care behavior in the male and the female mice. At a 30% concentration, fructose-intaking resulted in higher body mass gain and higher plasma cholesterol and triglycerides levels in the male and the female mice, whereas glucose intolerance was more pronounced in the male mice. Spatial memory impairments and lower self-care behavior were observed in the male and the female mice, while passive stress-coping behavior was observed only in the female mice. Collectively, high-fructose intake induces metabolic and behavioral alterations in mice, with the males being more susceptible to glucose metabolism dysfunctions and the females to depressive-like endophenotypes.

Role of Sirt3 in Differential Sex-Related Responses to a High-Fat Diet in Mice

Metabolic homeostasis is differently regulated in males and females. Little is known about the mitochondrial Sirtuin 3 (Sirt3) protein in the context of sex-related differences in the development of metabolic dysregulation. To test our hypothesis that the role of Sirt3 in response to a high-fat diet (HFD) is sex-related, we measured metabolic, antioxidative, and mitochondrial parameters in the liver of Sirt3 wild-type (WT) and knockout (KO) mice of both sexes fed with a standard or HFD for ten weeks. We found that the combined effect of Sirt3 and an HFD was evident in more parameters in males (lipid content, glucose uptake, pparγ, cyp2e1, cyp4a14, Nrf2, MnSOD activity) than in females (protein damage and mitochondrial respiration), pointing towards a higher reliance of males on the effect of Sirt3 against HFD-induced metabolic dysregulation. The male-specific effects of an HFD also include reduced Sirt3 expression in WT and alleviated lipid accumulation and reduced glucose uptake in KO mice. In females, with a generally higher expression of genes involved in lipid homeostasis, either the HFD or Sirt3 depletion compromised mitochondrial respiration and increased protein oxidative damage. This work presents new insights into sex-related differences in the various physiological parameters with respect to nutritive excess and Sirt3.

Gender Differences in the Pattern of Socio-Demographics Relevant to Metabolic Syndrome Among Kenyan Adults with Central Obesity at a Mission Hospital in Nairobi, Kenya

INTRODUCTION

Metabolic syndrome (MetS) is a risk factor for cardiovascular-related morbidity and mortality. Although the risk factors for MetS are well documented, differences in gender-based demographics among Kenyan adults with central obesity are lacking.

AIM

Determine gender differences in the pattern of socio-demographics relevant to metabolic syndrome among Kenyan adults with central obesity at a mission hospital, Nairobi.

METHODS

A cross-sectional baseline survey involving adults (N = 404) with central obesity aged 18-64 years, as part of a community-based lifestyle intervention study. Respondents were systematically sampled using the International Diabetes Federation definition for MetS. Lifestyle characteristics, anthropometric, clinical and biochemical markers were measured and analyzed using SPSS.

RESULTS

High (87.2%) MetS prevalence associated with advanced age in males (p < 0.001) and females (p = 0.002) was observed. MetS was likely among divorced/separated/widowed (p = 0.021) and high income males (p = 0.002) and females (p = 0.017) with high income. Unemployed males (p = 0.008) and females with tertiary education (p = 0.019) were less likely to have MetS. Advanced age was likely to lead to high blood pressure, fasting blood glucose and triglycerides (p < 0.05). Males were more likely (p = 0.026) to have raised triglycerides, while females (p < 0.001) had low high density lipoproteins.

CONCLUSION

A high prevalence of MetS associated with social and gender differences among Kenyan adults with central obesity. These underscore the need to look beyond the behavioral and biological risks and focus on every nuance of gender differences in addressing MetS and CVDs.

Prevalence and Associated Factors of Metabolic Syndrome among Patients with Severe Mental Illness Attending a Tertiary Hospital in Southwest Uganda

Globally, the prevalence of metabolic syndrome (MetS) and its components which are the major cardiovascular disease (CVD) risk factors, is higher among patients with severe mental illness (SMI) compared to the general population. This is mainly due to the deleterious lifestyles characterized by physical inactivity, excessive alcohol consumption, smoking, and unhealthy diets common among patients with SMI as well as due to cardiometabolic effects of psychotropic medications. Despite these conditions being highly prevalent among patients with SMI, little attention is given to these conditions during routine reviews in the mental health clinics in most low-income countries including Uganda. The main objective of this study was to determine the prevalence and associated factors of MetS among patients with SMI at Mbarara Regional Referral Hospital (MRRH), a tertiary hospital in southwestern Uganda. Through a cross-sectional study at the mental health clinic of the hospital, we recruited 304 patients with SMI and evaluated them for MetS using the National Cholesterol Education Programme Adult Treatment Panel III (NCEP ATP III) criteria. We defined the prevalence of MetS as the proportion of patients meeting the NCEP ATP III criteria. We used logistic regression to evaluate associations between MetS and independent variables. We included a total of 302 (44.37% male, 55.63% female) patients with a diagnosis of SMI in the analysis. The prevalence of MetS was 23.51% (95% CI 18.84–28.71). At multivariable logistic regression, age >40 years and long duration of mental illness (>10 years) were significantly associated with MetS. The prevalence of MetS is high among patients with psychiatric disorders, and thus metabolic screening, especially among the high-risk groups, is critical.

Overweight, the major determinant of metabolic syndrome among industrial workers in Kerala, India: Results of a cross-sectional study

AIM

To determine the prevalence and associated risk factors of metabolic syndrome (MS) among industrial workers in Kerala, India.

MATERIALS AND METHODS

We measured fasting plasma glucose (FPG), triglycerides, high density lipoprotein cholesterol, waist circumference, systolic blood pressure and diastolic blood pressure among 2287 industrial workers (mean age 46 years, men 70%) from selected industries of two southern most Kerala districts using standard protocol in 2009. MS was defined according to international diabetes federation (IDF), Adult Treatment Panel (ATP-III) and American Heart Association(AHA)/National Heart Lung and Blood Institute (NHLBI) criteria (Harmonization). Age-standardized prevalence of MS was assessed for men and women. Multivariable logistic regression models were developed to find the associated factors of MS.

RESULTS

Age-standardized prevalence of MS was 14% (men 14%, women 15%), 19% (men 19%, women 21%) and 27% (men 30%, women 21%) as per IDF, ATP-III and Harmonization criteria respectively. Overweight adults were nine times (OR 9.41, 95% CI 7.34-12.06), twelve times (OR 11.80 CI 9.38-14.84), and four times (OR 3.56, CI 2.94-4.29) more likely to have MS compared to their counterparts according to IDF, ATP-III and Harmonization criteria respectively. Older adults and current alcohol users were more likely to have MS compared to their counterparts. Women were more likely to have MS as per IDF and ATP-III criteria.

CONCLUSIONS

MS prevalence was high among Industrial workers who generally have good access to health care. Overweight and other predictors of MS need to be addressed to reduce MS prevalence in this population.

Trans-fatty acids aggravate anabolic steroid-induced metabolic disturbances and differential gene expression in muscle, pancreas and adipose tissue

AIMS

Although anabolic steroids (AS) and trans-fatty acids overload exerts systemic toxicity and are independent risk factors for metabolic and cardiovascular disorders, their interaction remains poorly understood. Thus, we investigated the impact of a diet rich in trans-fatty acids (HFD) combined with AS on glycemic control, lipid profile, adipose tissue, skeletal muscle and pancreas microstructure and expression of genes involved in energy metabolism.

MAIN METHODS

Forty-eight C57BL/6 mice were randomized into 6 groups treated for 12 weeks with a standard diet (SD) or a diet rich in C18:1 trans-fatty isomers (HFD), alone or combined with 10 or 20 mg/kg testosterone cypionate (AS).

KEY FINDINGS

Our results indicated that AS improved glycemic control, upregulated gene expression of Glut-4 and CPT-1 in skeletal muscle, FAS, ACC and UCP-1 in adipose tissue. AS also reduced total and LDL cholesterol in mice fed a SD. When combined with the HFD, AS was unable to induce microstructural adaptations in adipose tissue, pancreatic islets and β-cells, but potentiated GCK and Glut-2 (pancreas) and Glut-4 and CPT-1 (skeletal muscle) upregulation. HFD plus AS also downregulated FAS and ACC gene expression in adipose tissue. Combined with HFD, AS increased triacylglycerol circulating levels, improved insulin sensitivity and glycemic control in mice.

SIGNIFICANCE

Our findings indicated that HFD and AS can interact to modulates glycemic control and lipid profile by a mechanism potentially related with a reprogramming of genes expression in organs such as the pancreas, adipose tissue and skeletal muscle.

Beneficial Role of Phytochemicals on Oxidative Stress and Age-Related Diseases

Aging is related to a number of functional and morphological changes leading to progressive decline of the biological functions of an organism. Reactive Oxygen Species (ROS), released by several endogenous and exogenous processes, may cause important oxidative damage to DNA, proteins, and lipids, leading to important cellular dysfunctions. The imbalance between ROS production and antioxidant defenses brings to oxidative stress conditions and, related to accumulation of ROS, aging-associated diseases. The purpose of this review is to provide an overview of the most relevant data reported in literature on the natural compounds, mainly phytochemicals, with antioxidant activity and their potential protective effects on age-related diseases such as metabolic syndrome, diabetes, cardiovascular disease, cancer, neurodegenerative disease, and chronic inflammation, and possibly lower side effects, when compared to other drugs.

Estrogen-mediated gut microbiome alterations influence sexual dimorphism in metabolic syndrome in mice

BACKGROUND

Understanding the mechanism of the sexual dimorphism in susceptibility to obesity and metabolic syndrome (MS) is important for the development of effective interventions for MS.

RESULTS

Here we show that gut microbiome mediates the preventive effect of estrogen (17β-estradiol) on metabolic endotoxemia (ME) and low-grade chronic inflammation (LGCI), the underlying causes of MS and chronic diseases. The characteristic profiles of gut microbiome observed in female and 17β-estradiol-treated male and ovariectomized mice, such as decreased Proteobacteria and lipopolysaccharide biosynthesis, were associated with a lower susceptibility to ME, LGCI, and MS in these animals. Interestingly, fecal microbiota-transplant from male mice transferred the MS phenotype to female mice, while antibiotic treatment eliminated the sexual dimorphism in MS, suggesting a causative role of the gut microbiome in this condition. Moreover, estrogenic compounds such as isoflavones exerted microbiome-modulating effects similar to those of 17β-estradiol and reversed symptoms of MS in the male mice. Finally, both expression and activity of intestinal alkaline phosphatase (IAP), a gut microbiota-modifying non-classical anti-microbial peptide, were upregulated by 17β-estradiol and isoflavones, whereas inhibition of IAP induced ME and LGCI in female mice, indicating a critical role of IAP in mediating the effects of estrogen on these parameters.

CONCLUSIONS

In summary, we have identified a previously uncharacterized microbiome-based mechanism that sheds light upon sexual dimorphism in the incidence of MS and that suggests novel therapeutic targets and strategies for the management of obesity and MS in males and postmenopausal women.

Longitudinal Examination of Links Between Risk Factors for the Metabolic Syndrome and Both Age and Fasting Glucose Levels in Nondiabetic Subjects

BACKGROUND

Previous evaluations in nondiabetic subjects revealed statistically significant correlations between fasting blood glucose (FBG) levels used as an estimate of insulin resistance and many components constituting the metabolic syndrome. Similar significant correlations were not found employing chronological age as the independent variable in the same nondiabetic individuals.

OBJECTIVE

The major purpose here was to replicate as well as corroborate the previous cross-sectional observations, emphasizing results obtained from data collected longitudinally.

METHODS

Material was assessed from 99 nondiabetic volunteers who had undergone 2 separate baseline measurements carried out over a minimum of 5 and up to a maximum of 20 years.

RESULTS

Findings from the starting baseline measurements mimicked many observations perceived in the earlier published cross-sectional material. The following correlations with elements constituting the metabolic syndrome using FBG as an independent variable were once more statistically significantly positive: scale weight, fat mass, circulating levels of triglycerides and high-sensitivity C-reactive protein (hsCRP). High-density lipoprotein (HDL) cholesterol was once again appropriately significant in a negative direction. In contrast, the same correlations were generally nonsignificant when age replaced FBG as the independent variable. Examining the 2 data sets over the 5-20-year intervals, FBG increased statistically significantly over time. However, the average increase clinically was relatively minor: -92.1 mg/dL ± 1.1 (SEM) vs 95.1 mg/dL ± 1.1 (SEM), p < 0.007. When the actual changes (delta) in the dependent parameters were correlated with the individual passages of time (intervals in years), only downward changes in aspartate aminotransferase (AST) levels were statistically significant. Fat-free mass showed a trend downward, whereas fat mass, trunk fat, and triglycerides merely demonstrated trends upward.

CONCLUSION

Current findings gathered over years are consistent with the original hypothesis that maintaining relatively low, stable circulating glucose levels during aging retards the development and intensity of many common manifestations of the metabolic syndrome.

Reproductive factors in relation to heart failure in women: A systematic review

BACKGROUND

The biological mechanisms underlying the sex-related differences in risk of heart failure are still not well understood. The aim of this review was to provide an overview of the current evidence on the association between reproductive factors and risk of heart failure in women.

METHODS

A systematic review of the literature was conducted. PubMed and Embase databases were searched for publications on the following reproductive factors as potential risk factors for heart failure in women: age at menarche, duration and frequency of the menstrual cycle, reproductive lifespan, use of contraception, polycystic ovarian syndrome (PCOS), pregnancy characteristics (e.g. parity), pregnancy complications (e.g. preeclampsia), induced abortion, history of breastfeeding, fertility status, use of assisted reproductive methods, hysterectomy, age at menopause, and use of hormone replacement therapy (HRT).

RESULTS

Twenty-one studies were eligible for inclusion. Hypertensive pregnancy disorders, preterm delivery or small-for-gestational-age (SGA) infants, shorter reproductive duration, and early menopause were risk factors for heart failure in women. It was suggested that PCOS, fertility therapy, gestational diabetes, and age at first pregnancy were not related to risk of heart failure, but a potential relation cannot be fully excluded as most studies were not of sufficient quality. Conflicting results were found for the associations between risk of heart failure and hysterectomy, gravidity and parity, and HRT.

CONCLUSION

Although some reproductive factors were considered risk factors for heart failure in women, the results were mostly conflicting or inconclusive. Further research is needed to confirm and expand the current evidence on the association between reproductive factors and risk of heart failure.

Gender Differences in Lifestyle Factors Associated with Metabolic Syndrome and Preliminary Metabolic Syndrome in the General Population: The Watari Study

Objective In Japan, metabolic syndrome (MetS) and preliminary metabolic syndrome (preMetS) are more prevalent in men; however, it remains unclear whether the relationship between these metabolic disorders and lifestyle factors is similar between genders. Methods We examined waist circumference, blood pressure, fasting blood, and various lifestyle factors in 3,166 individuals aged from 30-79 years of age from the Japanese general population. MetS was diagnosed on the basis of central obesity - assessed by waist circumference - plus two or more of the following cardio-metabolic risks according to Japanese criteria: high blood pressure, hyperglycemia, and lipid abnormality. Central obesity plus one of the risks was defined as preMetS. Results Men had a significantly higher prevalence of MetS (23.3% vs. 8.7%, p<0.001) and preMetS (21.2% vs. 10.2%, p<0.001) than women. An age-adjusted logistic regression analysis revealed that heavy drinkers were associated with an increased probability of MetS (odds ratio, 1.91: 95% confidence interval, 1.29-2.83) and preMetS (1.69: 1.11-2.58); fast eaters were also related to preMetS (1.83: 1.33-2.55) and MetS (1.55: 1.12-2.15) in men. Lacking regular exercise was significantly associated with preMetS (1.38: 1.03-1.85), but not MetS. In women, preMetS was significantly associated with fast eaters and lacking regular exercise (1.44: 1.01-2.07 and 1.41: 1.02-1.96, respectively); a stepwise increase in each odds ratio (2.02: 1.40-2.91 and 1.47: 1.03-2.09, respectively) was also observed for MetS. Conclusion The relationships between lifestyle factors and MetS or preMetS differed between men and women, which suggests the need for gender-specific lifestyle modification to effectively prevent MetS.

Does long-term androgen deficiency lead to metabolic syndrome in middle-aged rats?

Evidence from clinical observational studies and animal experiments suggests that hypogonadism is associated with the metabolic syndrome. In most of the experiments, androgen deficiency is induced by gonadectomy in the adulthood and relatively short-term effects of hypogonadism on metabolic parameters are usually observed. The purpose of this study was to evaluate the metabolic effects of long-term androgen deficiency starting before puberty in middle-aged male rats. The components of the metabolic syndrome were examined in male, female and gonadectomized male rats at the age of 18months. Sex differences were observed in plasma testosterone, cholesterol, high-density lipoproteins and also in body weight and in glycemia dynamics during oral glucose tolerance test. Gonadectomy and long-term hypogonadism did not affect most of the analyzed metabolic parameters such as blood pressure, glycemia, plasma insulin and uric acid. The only exception was the significantly higher liver enzymes in plasma and triacylglycerol in liver found in gonadectomized males. Except low-density lipoprotein, neither treatment of middle-aged males and females with letrozole, nor supplementation of estradiol as the metabolite of testosterone in gonadectomized male rats changed any of the observed metabolic parameters. Our results suggest that long-term hypogonadism started before puberty does not induce metabolic syndrome in middle-aged male rats, but may affect the liver. Sex differences in metabolic parameters in middle-aged rats are not mediated by testosterone. Whether hypogonadism predispose to metabolic syndrome in combination with other risk factors needs further clarification.

Association of lipid peroxidation and antioxidant status with metabolic syndrome in Iranian healthy elderly women

The interconnection between aging and metabolic syndrome (MetS) and their effect on oxidative stress (OxS) status lacks adequate information. Additionally, the age-related changes of antioxidant defenses and OxS in senior women with MetS in comparison to healthy senior women are not yet established. We analyzed the correlation between oxidative defense status and OxS with MetS components. Through further examination of MetS and aging, we aimed to determine their independent effects on OxS and oxidative defense status. This community-based cross-sectional study was conducted in the rural area of Babol, Iran. A total of 75 women of ≥60 years of age with MetS along with 89 women with similar conditions without the MetS, serving as the control group, were studied. Blood glucose, lipid profile, malondialdehyde (MDA) and total antioxidant capacity (TAC) were determined. Data were analyzed using multiple linear regression, ANOVA and independent t-tests. MDA and TAC levels independently showed a significant correlation with triglyceride (TG), waist circumference, fasting blood glucose and high-density lipoprotein cholesterol (HDL-C). As suggested by the standardized B (0.810, -0.783, P<0.001; -0.052, P<0.001, 0.047, P<0.01), TG followed by HDL-C were the most strongly correlated factors with MDA and TAC. Furthermore, MetS and age were independent risk factors for antioxidant activity reduction and OxS. However, MetS had a much higher predictive power than age (standardized B 0.573 for MetS and 0.376 for age, P<0.001). Aging and MetS, both lead to OxS, but the impact of MetS on this disorder was far greater than the effect of age. However, their cumulative effects can lead to a worsening of the situation. Therefore, early diagnosis and treatment of MetS, especially in the elderly can prevent any adverse impact of MetS.

Lean Fish Consumption Is Associated with Beneficial Changes in the Metabolic Syndrome Components: A 13-Year Follow-Up Study from the Norwegian Tromsø Study

BACKGROUND

Fish consumption may have beneficial effects on metabolic syndrome (MetS); however, limited information of such associations exists. This study investigated possible associations between fish consumption and changes in MetS components during a 13-year follow-up period.

METHODS

The sample included participants (26-69 years) from the Tromsø Study 4 (1994-1995, n = 23,907) and Tromsø Study 6 (2007-2008, n = 12,981). Data were collected using questionnaires including food frequency questions, non-fasting blood samples, and physical examinations. MetS was defined using the Joint Interim Societies (JIS) definition, in which one point was given for each MetS criteria fulfilled (metabolic score). Longitudinal analyses were performed using Linear mixed models.

RESULTS

For both genders, lean fish consumption once a week or more was significantly associated with decreased future metabolic score, decreased triglycerides, and increased high-density lipoprotein (HDL)-cholesterol, whereas decreased waist circumference and blood pressure was identified only for men (age adjusted models). Fatty fish consumption was significantly associated with increased waist circumference for both genders and increased HDL-cholesterol levels in men. Conclusion: The results suggest that fatty and lean fish consumption may influence MetS differently and that lean fish consumption in particular seems to be associated with beneficial changes in the MetS components.

Middle-Aged Diabetic Females and Males Present Distinct Susceptibility to Alzheimer Disease-like Pathology

Type 2 diabetes (T2D) is a highly concerning public health problem of the twenty-first century. Currently, it is estimated that T2D affects 422 million people worldwide with a rapidly increasing prevalence. During the past two decades, T2D has been widely shown to have a major impact in the brain. This, together with the cognitive decline and increased risk for dementia upon T2D, may arise from the complex interaction between normal brain aging and central insulin signaling dysfunction. Among the several features shared between T2D and some neurodegenerative disorders (e.g., Alzheimer disease (AD)), the impairment of insulin signaling may be a key link. However, these may also involve changes in sex hormones' function and metabolism, ultimately contributing to the different susceptibilities between females and males to some pathologies. For example, female sex has been pointed as a risk factor for AD, particularly after menopause. However, less is known on the underlying molecular mechanisms or even if these changes start during middle-age (perimenopause). From the above, we hypothesized that sex differentially affects hormone-mediated intracellular signaling pathways in T2D brain, ultimately modulating the risk for neurodegenerative conditions. We aimed to evaluate sex-associated alterations in estrogen/insulin-like growth factor-1 (IGF-1)/insulin-related signaling, oxidative stress markers, and AD-like hallmarks in middle-aged control and T2D rat brain cortices. We used brain cortices homogenates obtained from middle-aged (8-month-old) control Wistar and non-obese, spontaneously T2D Goto-Kakizaki (GK) male and female rats. Peripheral characterization of the animal models was done by standard biochemical analyses of blood, plasma, or serum. Steroid sex hormones, oxidative stress markers, and AD-like hallmarks were given by specific ELISA kits and colorimetric techniques, whereas the levels of intracellular signaling proteins were determined by Western blotting. Albeit the high levels of plasma estradiol and progesterone observed in middle-aged control females suggested that they were still under their reproductive phase, some gonadal dysfunction might be already occurring in T2D ones, hence, anticipating their menopause. Moreover, the higher blood and lower brain cholesterol levels in female rats suggested that its dysfunctional uptake into the brain cortex may also hamper peripheral estrogen uptake and/or its local brain steroidogenic metabolism. Despite the massive drop in IGF-1 levels in females' brains, particularly upon T2D, they might have developed some compensatory mechanisms towards the maintenance of estrogen, IGF-1, and insulin receptors function and of the subsequent Akt- and ERK1/2-mediated signaling. These may ultimately delay the deleterious AD-like brain changes (including oxidative damage to lipids and DNA, amyloidogenic processing of amyloid precursor protein and increased tau protein phosphorylation) associated with T2D and/or age (reproductive senescence) in female rats. By demonstrating that differential sex steroid hormone profiles/action may play a pivotal role in brain over T2D progression, the present study reinforces the need to establish sex-specific preventive and/or therapeutic approaches and an appropriate time window for the efficient treatment against T2D and AD.

The association between gender difference with metabolic syndrome, metabolic syndrome score and serum vitamin D levels in Korean adults

This study assessed the association between gender difference with metabolic syndrome (MetS), metabolic syndrome score (MSS) and serum vitamin D levels in Korean adults. Analyses were restricted to 5147 adults (2162 men; 2985 women) aged 20 and older, using the 2012 Korean National Health and Nutrition Examination Survey (KNHANES) data. In the non-adjusted model, serum 25-hydroxyvitamin D [25(OH)D] levels were inversely associated with MetS (p = .001) and MSS (p = .009) in men, but positively associated with MetS (p = .002) and MSS (p < .001) in women. However, when adjusted for related variables (including age), serum 25(OH)D levels were inversely associated with MetS (p < .001) and MSS (p < .001) in men, but were not associated with MetS (p = .200) and MSS (p = .541) in women. In conclusion, increases in MetS and its components were inversely associated with the serum vitamin D concentration in men.

Lean fish consumption is associated with lower risk of metabolic syndrome: a Norwegian cross sectional study

Background

Fish consumption may have a role in reducing the prevalence of metabolic syndrome (MetS). The aim of this study was to identify associations between fish consumption and MetS and its components, especially regarding differences concerning consumption of fatty and lean fish.

Methods

This cross sectional study uses data from the Tromsø 6 survey (2007–08), where a sample of 12 981 adults, aged 30–87 years (47 % men) from the Norwegian general population was included. Fish consumption was assessed using food frequency questionnaires (FFQ). Blood sample assessments, anthropometric and blood pressure measurements were carried out according to standard protocols. MetS was defined using the Joint Interim Societies (JIS) definition. All tests were two-sided. Analyses were performed using IBM SPSS Statistics 22 (Pearson’s correlation, Chi-Square tests, analysis of variance (ANOVA), linear and logistic regression models).

Results

Mean age was 57.5, and the prevalence of MetS was 22.6 %. Fish consumption once a week or more was associated with lower risk of having MetS among men (OR 0.85, CI 95 % 0.74 to 0.98, P = 0.03). In the adjusted models, lean fish consumption was associated with a decreased risk of having MetS, whereas fatty fish consumption was not associated with a decreased risk of having MetS. Both an increased fatty and lean fish consumption (0–1 times per month, 2–3 times per month, 1–3 times per week, 4–6 times per week, 1–2 times per day) were associated with decreased serum triglyceride (TG), and increased high-density lipoprotein cholesterol (HDL-C).

Conclusions

Fish consumption may be associated with a lower risk of having MetS and consumption of lean fish seems to be driving the association. Further investigation is warranted to establish associations between fish consumption and MetS.

Associations between fish consumption and metabolic syndrome. A large cross-sectional study from the Norwegian Tromsø Study: Tromsø 4

BACKGROUND

Fish consumption may prevent or improve metabolic health. The aim of this study was to identify associations between fish consumption, both fatty and lean, and metabolic syndrome and its components.

METHODS

Associations between fish consumption and metabolic syndrome and its components were studied in a large sample from a Norwegian population (N = 23,907), using cross-sectional data from the Tromsø 4 survey (1994-1995). Metabolic syndrome was defined using the JIS definition, and dietary data was collected using food frequency questionnaires (FFQ). Blood samples were taken for biochemical assessments, and anthropometric and blood pressure measurements were carried out according to standard protocols.

RESULTS

In this sample from an adult population (aged 26-70 years, mean age 44 years, SD 11.69, 48 % men), a higher fish consumption (≥1/week) was associated with a healthier lipid profile with increased HDL-C and decreased TG. Participants aged 60-70 years consuming fish once a week or more had significantly lower risk of having MetS, compared to those consuming fish less than once a week (OR 0.64, CI 0.45-0.91). When investigating fatty and lean fish separately, only lean fish consumption was associated with a reduced the risk of having MetS. Participants aged 60-70 years consuming lean fish once a week or more, had lower risk of having MetS compared to those consuming lean fish less than once a week (OR 0.65, CI 0.48-0.87). No association was found for consumption of fatty fish, or for lean fish in the age groups <45 or 45-59 years.

CONCLUSIONS

These results indicates that fatty and lean fish consumption influences MetS risk differently, possibly also related to age. However, further investigation is needed to establish how various fish consumption may influence MetS and its components, particularly when stratified by fatty and lean fish.

Gender and Age Impacts on the Association Between Thyroid Function and Metabolic Syndrome in Chinese

The relationship between thyroid dysfunction and metabolic syndrome (MS) is complex. We aimed to explore the impact of gender and age on their association in a large Chinese cohort. This cross-sectional study enrolled 13,855 participants (8532 male, 5323 female), who self-reported as healthy without any known previous diseases. Clinical data including anthropometric measurements, thyroid function, and serum metabolic parameters were collected. The associations between thyroid function and MS of both genders were analyzed separately after dividing thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and age into subgroups. MS risks were calculated by binary logistic regression models. Young males had significantly higher MS prevalence than females, yet after menopause, females had higher prevalence than males. Females had higher incidence of thyroid dysfunction than males. By using TSH quartiles as the categorical variables and the lowest quartile as reference, significantly increased MS risk was demonstrated in quartile 4 for males, yet quartiles 3 and 4 for females. By using FT3 quartiles as the categorical variables, significantly increased MS risk was demonstrated in quartile 2 to 4 for females only. By using age subgroups as the categorical variables, significantly increased MS risk was shown in both genders, with females (4.408-58.455) higher than males (2.588-4.943). Gender and age had substantial influence on thyroid function and MS. Females with high TSH and high FT3 had higher MS risks than males. Aging was a risk for MS, especially for females. Urgent need is necessary to initiate interventional programs.

Mitochondrial maintenance failure in aging and role of sexual dimorphism

Gene expression changes during aging are partly conserved across species, and suggest that oxidative stress, inflammation and proteotoxicity result from mitochondrial malfunction and abnormal mitochondrial-nuclear signaling. Mitochondrial maintenance failure may result from trade-offs between mitochondrial turnover versus growth and reproduction, sexual antagonistic pleiotropy and genetic conflicts resulting from uni-parental mitochondrial transmission, as well as mitochondrial and nuclear mutations and loss of epigenetic regulation. Aging phenotypes and interventions are often sex-specific, indicating that both male and female sexual differentiation promote mitochondrial failure and aging. Studies in mammals and invertebrates implicate autophagy, apoptosis, AKT, PARP, p53 and FOXO in mediating sex-specific differences in stress resistance and aging. The data support a model where the genes Sxl in Drosophila, sdc-2 in Caenorhabditis elegans, and Xist in mammals regulate mitochondrial maintenance across generations and in aging. Several interventions that increase life span cause a mitochondrial unfolded protein response (UPRmt), and UPRmt is also observed during normal aging, indicating hormesis. The UPRmt may increase life span by stimulating mitochondrial turnover through autophagy, and/or by inhibiting the production of hormones and toxic metabolites. The data suggest that metazoan life span interventions may act through a common hormesis mechanism involving liver UPRmt, mitochondrial maintenance and sexual differentiation.

Metabolic syndrome, aging and involvement of oxidative stress

The prevalence of the metabolic syndrome, a cluster of cardiovascular risk factors associated with obesity and insulin resistance, is dramatically increasing in Western and developing countries. This disorder consists of a cluster of metabolic conditions, such as hypertriglyceridemia, hyper-low-density lipoproteins, hypo-high-density lipoproteins, insulin resistance, abnormal glucose tolerance and hypertension, that-in combination with genetic susceptibility and abdominal obesity-are risk factors for type 2 diabetes, vascular inflammation, atherosclerosis, and renal, liver and heart diseases. One of the defects in metabolic syndrome and its associated diseases is excess of reactive oxygen species. Reactive oxygen species generated by mitochondria, or from other sites within or outside the cell, cause damage to mitochondrial components and initiate degradative processes. Such toxic reactions contribute significantly to the aging process. In this article we review current understandings of oxidative stress in metabolic syndrome related disease and its possible contribution to accelerated senescence.