Gender difference in adiponectin associated with cardiovascular mortality

Interaction of Adiponectin Genotypes and Insulin Resistance on the Occurrence of Taiwanese Metabolic Syndrome

Backgrounds

Adiponectin (apM1) may affect insulin sensitivity, and tumor necrosis factor (TNF-α) can inhibit the binding of insulin and insulin receptors. However, whether apM1 and TNF-α genes influence the development of metabolic syndrome (MetS) preceded by insulin resistance is unclear. The current study examines the interactions between the apM1 +45 genotypes, TNF-α -308 genotypes, and insulin resistance on the occurrence of MetS.

Methods

A total of 329 community residents were recruited, and their personal characteristics were collected. Waist circumference and biochemical markers were examined for determining MetS. Genotypes were identified by the polymerase chain reaction.

Results

After adjusting for the confounding effects, compared to apM1 +45 GG and GT genotypes carriers with HOMR-IR less than 2.0, those carriers with HOMA-IR greater than 2.0 had an increased MetS risk (OR = 4.35, 95% CI 2.14-8.85). Further, apM1 +45 TT carriers with HOMA-IR greater than 2.0 experienced a higher MetS risk (OR = 5.91, 95% CI 2.78-12.54). A significant interaction of the apM1 +45 genotype and insulin resistance on the MetS development was observed (P = 0.04).

Conclusion

Our data suggested that apM1 +45 genotypes might modify the effect of insulin resistance on the development of Taiwanese MetS.

Metabolic Syndrome for Cardiovascular Disease Morbidity and Mortality Among General Japanese People: A Mini Review

Background

The importance of management of metabolic syndrome (MetS) for risk reduction of cardiovascular disease (CVD) has been recognized worldwide. Because of the comparatively unique characteristics of bodily figure/obesity and incident CVD in Japan, the relevance of MetS on CVD can be still discussed among Japanese people. The present study aimed to review briefly the relationship of MetS with CVD morbidity/mortality among general Japanese people.

Methods

Population-based prospective cohort studies evaluating the predictive value of MetS on CVD morbidity/mortality via a PubMed search up to 2019 were summarized.

Results

We identified two studies on morbidity that reported MetS to predict CVD morbidity. We identified three studies on mortality, and these studies showed an increased direction of hazard ratio (HR) of CVD mortality, while one study reported an insignificant prediction of MetS for CVD mortality. In the meta-analysis method, MetS significantly predicted CVD morbidity (HR=1.71 [95% confidence interval=1.34–2.18] in men and HR=1.89 [95% confidence interval=1.45–2.46] in women) as well as CVD mortality (HR=1.68 [95% confidence interval=1.37–2.06] in men and HR=1.73 [95% confidence interval=1.39–2.15] in women).

Conclusion

Among general Japanese people, MetS can be a positive predictor of CVD morbidity/mortality. Since the studies are limited, more research is needed to establish the findings.

Effect of atorvastatin treatment on circulating adiponectin: a meta-analysis of randomized controlled trials

Background

Influences of atorvastatin on atherosclerosis and glycemic metabolism may be related to its potential impact on circulating adiponectin, an adipocyte that exerts anti-inflammatory, ant-atherosclerotic, and anti-oxidative effects. However, results of previous randomized controlled trials (RCTs) were not consistent. We performed a meta-analysis of RCTs to systematic evaluate the influence of atorvastatin on circulating adiponectin.

Methods

Relevant studies were identified via search of electronic databases of PubMed, Embase, and Cochrane’s Library. A random-effect model was applied to pool the results via incorporating the potential heterogeneity. Predefined meta-regression and subgroup analyses were used to evaluate the influences of study characteristics on the outcome.

Results

Fourteen datasets from ten RCTs including 931 patients were included. Pooled results showed that atorvastatin did not significantly affect circulating adiponectin as compared with controls (weighed mean difference = − 0.27 μg/mL, 95% confidence interval: − 0.89 to 0.35 μg/mL, p = 0.39). Results of univariate meta-regression analyses showed that study characteristics including number of patients, mean age, proportion of male patients, body mass index, dose of atorvastatin, or treatment duration did not significantly affect the outcome (p all > 0.05). Moreover, subgroup analyses showed that atorvastatin did not significantly affect circulating adiponectin in studies stratified according to these study characteristics (p all > 0.05).

Conclusions

Atorvastatin treatment does not significantly affect circulating adiponectin. Influences of atorvastatin on atherosclerosis and glycemic metabolism are not likely to be mediated by modulation of circulating adiponectin.

Gender difference and genetic variance in lipoprotein receptor-related protein 1 is associated with mortality

Cardiovascular diseases are an important health resource problem and studies have shown a genetic association between single nucleotide polymorphisms (SNPs) and cardiovascular diseases. According to the literature, lipoprotein receptor-related protein 1 (LRP1) is associated with coronary artery disease. The aim of the present study was to evaluate a possible association between different genotypes of LRP1 and all-cause and cardiovascular mortality from a gender perspective. In the present study, 489 elderly community-living people were invited to participate. Clinical examination, echocardiography and blood sampling including SNP analyses of LRP1 (rs1466535) were performed, including the T/T, C/T and C/C genotypes, and the participants were followed for 6.7 years. During the follow-up period, 116 (24%) all-cause and 75 (15%) cardiovascular deaths were registered. In the female population, the LRP1 of the T/T or C/T genotype exhibited a 5.6-fold increased risk of cardiovascular mortality and a 2.8-fold increased risk of all-cause mortality compared with the C/C genotype. No such genotype differences could be seen in the male population. Gender differences could be seen regarding the risk of mortality in the different genotypes. Females with the LRP1 T/T or C/T genotypes exhibited a significantly increased risk of both all-cause and cardiovascular mortality compared with the C/C genotypes. Therefore, more individualized cardiovascular prevention and treatment should be prioritized. However, since this was a small study, the observations should only be regarded as hypothesis-generating.

Leptin and adiponectin levels in major depressive disorder: A systematic review and meta-analysis

OBJECTIVES

To explore differences in adipokine levels (i.e., leptin and adiponectin levels) between adults with Major Depressive Disorder (MDD) and healthy controls (HC), and to discuss the possible role of adipokine regulation in the development and progression of MDD.

METHODS

A systematic review and meta-analysis were conducted based on the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. A systematic search was conducted for all English and Chinese peer-reviewed articles from inception to November 2017. A random effects model was used to calculate the standardized mean difference (SMD) of leptin and/or adiponectin levels in subjects diagnosed with MDD versus HC within a 95% confidence interval (CI).

RESULTS

Thirty-three studies were included in this meta-analysis. In total, 4,372 (52.3%) subjects with MDD and 3,984 (47.7%) HC were compared. We identified significant lower adiponectin levels in MDD compared to HC with a small effect size (ES) (SMD = -0.25; 95% CI: -0.48, -0.02; P < 0.001). However, no significant difference was observed in leptin levels between MDD subjects and HC (SMD = 0.13; 95% CI: -0.06, 0.31; P = 0.170). The heterogeneity in the results of our meta-analysis could not be completely explained by dividing subjects into subgroups. Results from subgroup analyses suggested that studies involving samples with BMI ≥ 25 had lower adiponectin levels in subjects with MDD compared to HC, and older age samples (i.e., age ≥ 40) with BMI ≥ 25 had both higher leptin levels and lower adiponectin levels in MDD subjects as compared to HC.

LIMITATIONS

The heterogeneity of included studies, small sample sizes, and potential publication bias were significant limitations.

CONCLUSIONS

The current systematic review and meta-analysis indicated that lower adiponectin levels may be associated with MDD. Moreover, the results suggest that males expressing lower adiponectin and leptin levels have an increased likelihood of developing MDD. Future studies should aim to investigate the manifestation of depressive phenotypes in older, obese populations with altered metabolic profiles resulting from adipokine dysregulation. The review has been registered with PROSPERO (registration number CRD42018082733).

Adiponectin circulating levels and 10-year (2002-2012) cardiovascular disease incidence: the ATTICA Study

PURPOSE

Adiponectin is an adipokine with anti-inflammatory and cardiovascular-protective properties. Existing epidemiological evidence is conflicting on the exact relationship between adiponectin and long-term cardiovascular disease (CVD) risk. Our aim was to prospectively assess whether circulating adiponectin is associated with long-term incident CVD.

METHODS

A population-based, prospective study in adults (>18 years) without previous CVD history (ATTICA study). Circulating total adiponectin levels were measured at baseline (2001-2002) in a sub-sample (n = 531; women/men: 222/309; age: 40 ± 11 years) of the ATTICA cohort and complete 10-year follow-up data were available in 366 of these participants (women/men: 154/212; age: 40 ± 12 years).

RESULTS

After adjusting for multiple factors, including age, sex, body mass index, waist circumference, smoking, physical activity, Mediterranean diet adherence, hypertension, diabetes, and hypercholesterolemia, our logistic regression analysis indicates that an increase in circulating total adiponectin levels by 1 unit was associated with 36% lower CVD risk (relative risk [RR]: 0.64, 95% confidence interval [CI] 0.42-0.96; p = 0.03). Further adjusting for interleukin-6 plasma levels had no significant impact (RR: 0.60, 95% CI 0.38-0.94; p = 0.03), while additional adjustment for circulating C-reactive protein (CRP) modestly attenuated this association (RR: 0.63, 95% CI 0.40-0.99; p = 0.046).

CONCLUSIONS

In our study, elevated circulating total adiponectin levels were associated with lower 10-year CVD risk in adults without previous CVD, independently of other established CVD risk factors. This association appeared to be modestly attenuated by CRP, yet was not mediated by interleukin-6 which is the main endocrine/circulating pro-inflammatory cytokine.

High Molecular Weight Adiponectin Levels are Neither Influenced by Adiponectin Polymorphisms Nor Associated with Insulin Resistance in Mixed-ancestry Hyperglycemic Subjects from South Africa

Background

High molecular weight (HMW) adiponectin has antiatherogenic, antiinflammatory and antidiabetic properties and these effects have been linked to its effect on high density lipoprotein cholesterol (HDL-c). Single nucleotide polymorphisms (SNPs) in the adiponectin gene influence adiponectin levels. We examined the relationship between HMW-adiponectin levels and cardiometabolic traits in normo- and hyperglycemic mixed ancestry South Africans and correlated these levels to two common polymorphisms.

Methods

HMW-adiponectin was determined in 101 subjects from the Cape Town Bellville South community-based study on a mixed ancestry population. Comparisons were made between individuals with normo- and hyperglycemia. Two common SNPs, ADIPOQ SNPs rs17300539 and rs266729, known to affect adiponectin levels were also tested for. Levels of HMW-adiponectin were then correlated with cardiometabolic traits in all groups.

Results

Levels of HMW-adiponectin were not significantly different in the normo- and hyperglycemic groups (median 11.6 vs. 10.5 μg/mL, p=0.3060) and in men and women (8.44 vs. 11.34 μg/mL, p=0.67). ADIPOQ SNPs rs17300539 and rs266729 did not influence levels of HMW-adiponectin. Robust correlation analyses revealed a significant positive correlation between HMW-adiponectin and HDL-c (r=0.45; 95%CI: 0.27–0.59), similarly in normo- and hyperglycemic participants (p > 0.99). This association was substantially attenuated in robust linear regressions adjusted for age, gender and adiposity.

Conclusions

Adiponectin levels in this population were not determined by the commonest SNPs of the adiponectin gene, were unaffected by glycemic status; but were significantly correlated with HDL-c levels. Previous studies have attributed some of the beneficial effects of adiponectin to its effect on HDL-c.

PDGF-D gene polymorphism is associated with increased cardiovascular mortality in elderly men

Background

Platelet-derived growth factor (PDGF) D has been reported to be active in fibroblasts, and in areas of myocardial infarction. In this longitudinal study we evaluated the association between PDGF-D polymorphism and cardiovascular mortality, and attempted to discover whether specific genotype differences regarding risk could be observed, and if gender differences could be seen.

Methods

Four hundred seventy-six elderly community participants were included in this study. All participants underwent a clinical examination, echocardiography, and blood sampling including PDGF-D single nucleotide polymorphism (SNP) analyses of the rs974819 A/A, G/A and G/G SNP. The follow-up time was 6.7 years.

Results

No specific genotype of rs974819 demonstrated increased cardiovascular mortality in the total population, however, the male group with genotypes A/A and G/A demonstrated an increased risk that persisted in a multivariate evaluation where adjustments were made for well-known cardiovascular risk factors (2.7 fold compared with the G/G genotype). No corresponding finding was observed in the female group.

Conclusion

We report here for the first time that the genotypes G/A or A/A of the SNP rs974819 near PDGF-D exhibited a 2.7 fold increased cardiovascular mortality risk in males. Corresponding increased risk could not be observed in either the total population and thus not in the female group. However, the sample size is was small and the results should be regarded as hypothesis-generating, and thus more research in the field is recommended.

Neuroendocrinological and Epigenetic Mechanisms Subserving Autonomic Imbalance and HPA Dysfunction in the Metabolic Syndrome

Impact of environmental stress upon pathophysiology of the metabolic syndrome (MetS) has been substantiated by epidemiological, psychophysiological, and endocrinological studies. This review discusses recent advances in the understanding of causative roles of nutritional factors, sympathomedullo-adrenal (SMA) and hypothalamic-pituitary adrenocortical (HPA) axes, and adipose tissue chronic low-grade inflammation processes in MetS. Disturbances in the neuroendocrine systems for leptin, melanocortin, and neuropeptide Y (NPY)/agouti-related protein systems have been found resulting directly in MetS-like conditions. The review identifies candidate risk genes from factors shown critical for the functioning of each of these neuroendocrine signaling cascades. In its meta-analytic part, recent studies in epigenetic modification (histone methylation, acetylation, phosphorylation, ubiquitination) and posttranscriptional gene regulation by microRNAs are evaluated. Several studies suggest modification mechanisms of early life stress (ELS) and diet-induced obesity (DIO) programming in the hypothalamic regions with populations of POMC-expressing neurons. Epigenetic modifications were found in cortisol (here HSD11B1 expression), melanocortin, leptin, NPY, and adiponectin genes. With respect to adiposity genes, epigenetic modifications were documented for fat mass gene cluster APOA1/C3/A4/A5, and the lipolysis gene LIPE. With regard to inflammatory, immune and subcellular metabolism, PPARG, NKBF1, TNFA, TCF7C2, and those genes expressing cytochrome P450 family enzymes involved in steroidogenesis and in hepatic lipoproteins were documented for epigenetic modifications.