Association of rs2241766 and rs1501299 polymorphisms in the adiponectin gene with metabolic syndrome.

OBJECTIVE: To investigate the influence of adiponectin (APN) rs2241766 and rs1501299 polymorphisms on adiponectin levels and their association with metabolic syndrome (MetS). METHODS: Analyzed two polymorphisms (rs2241766 and rs1501299) of the adiponectin gene (ADIPOQ) in 210 MetS patients and 102 control patients using the polymerase chain reaction-restriction fragment length polymorphism method and DNA sequencing technology. RESULTS: The genotypes of the rs2241766 T/G and rs1501299 G/T polymorphism were significantly associated with serum APN levels in MetS patients. The ADIPOQ polymorphisms were associated with a risk of MetS when compared with that in healthy controls. TG and GG genotypes of rs2241766 were associated with a significantly elevated risk of MetS as compared with the TT genotype (OR = 1.32 and OR = 2.53). Subjects with the G allele appeared to have higher susceptibility to MetS than those with the T allele (OR = 2.21). In common with the findings for rs2241766, the rs1501299 GT and TT genotypes were associated with a significantly increased risk of MetS as compared with the GG genotype (OR = 1.51 and OR = 2.24). The susceptibility to MetS appeared to be higher in subjects with the T allele than in those with the G allele (OR = 1.88). CONCLUSIONS: The occurrence of MetS may be associated with genetic variations at the rs2241766 and rs1501299 loci, especially in individuals with T to G mutations (rs2241766) and G to T mutations (rs1501299). These mutations may lead to decreased APN levels and a higher risk of developing MetS.

Dietary apigenin ameliorates obesity-related hypertension through TRPV4-dependent vasorelaxation and TRPV4-independent adiponectin secretion.

BACKGROUND: Obesity-related hypertension is a major cardiovascular risk factor. Apigenin, a natural flavonoid in celery, induces vascular dilation via endothelial transient receptor potential channel vanilla 4 (TRPV4) channels. This study aimed to explore apigenin's potential to alleviate obesity-related hypertension in mice and its underlying mechanisms. METHODS: The C57BL/6 and TRPV4 knockout mice were fed a high-fat diet and subjected to dietary intervention with apigenin. Body weight and tail blood pressure of the mice were measured during the feeding. Vascular reactivity was assessed through a DMT wire myograph systems in vitro. The distribution and expression of adiponectin and pro-inflammatory markers in brown fat were detected. Injecting adeno-associated eight (AAV8) viruses into brown adipose tissue (BAT) to determine whether adiponectin is indispensable for the therapeutic effect of apigenin. Palmitic acid (PA) was used in mouse brown adipocytes to examine the detailed mechanisms regulating adiponectin secretion. RESULTS: Apigenin improved vasodilation and reduced blood pressure in obese mice, effects partly blocked in TRPV4 knockout. It also reduced weight gain independently of TRPV4. Apigenin increased adiponectin secretion from BAT; knockdown of adiponectin weakened its benefits. Apigenin downregulated Cluster of differentiation 38 (CD38), restoring Nicotinamide adenine dinucleotide+ (NAD+) levels and activating the NAD+/Sirtuin 1 (SIRT1) pathway, enhancing adiponectin expression. CONCLUSIONS: Our study indicates that dietary apigenin is suitable as a nonpharmaceutical intervention for obesity-related hypertension. In mechanism, in addition to improving vascular relaxation through the activation of endothelial TRPV4 channels, apigenin also directly alleviated adipose inflammation and increased adiponectin levels by inhibiting CD38.

The change of epicardial adipose tissue characteristics and vulnerability for atrial fibrillation upon drastic weight loss.

BACKGROUND: Obesity increases the risk of atrial fibrillation (AF). We hypothesize that 'obese' epicardial adipose tissue (EAT) is, regardless of comorbidities, associated with markers of AF vulnerability. METHODS: Patients >40y of age undergoing bariatric surgery and using <2 antihypertensive drugs and no insulin were prospectively included. Study investigations were conducted before and 1y after surgery. Heart rhythm and p-wave duration were measured through ECGs and 7-d-holters. EAT-volume and attenuation were determined on non-enhanced CT scans. Serum markers were quantified by ELISA. RESULTS: Thirty-seven patients underwent surgery (age: 52.1 ± 5.9y; 27 women; no AF). Increased p-wave duration correlated with higher BMI, larger EAT volumes, and lower EAT attenuations (p < 0.05). Post-surgery, p-wave duration decreased from 109 ± 11 to 102 ± 11ms. Concurrently, EAT volume decreased from 132 ± 49 to 87 ± 52ml, BMI from 43.2 ± 5.2 to 28.9 ± 4.6kg/m2, and EAT attenuation increased from -76.1 ± 4.0 to -71.7 ± 4.4HU (p <0.001). Adiponectin increased from 8.7 ± 0.8 to 14.2 ± 1.0 µg/ml (p <0.001). However, decreased p-wave durations were not related to changed EAT characteristics, BMI or adiponectin. CONCLUSION: In this explorative study, longer p-wave durations related to higher BMIs, larger EAT volume, and lower EAT attenuations. P-wave duration and EAT volume decreased, and EAT attenuation increased upon drastic weightloss. However, there was no relation between decreased p-wave duration and changed BMI or EAT characteristics.

Prediction of gestational diabetes mellitus by multiple biomarkers at early gestation.

BACKGROUND: It remains unclear which early gestational biomarkers can be used in predicting later development of gestational diabetes mellitus (GDM). We sought to identify the optimal combination of early gestational biomarkers in predicting GDM in machine learning (ML) models. METHODS: This was a nested case-control study including 100 pairs of GDM and euglycemic (control) pregnancies in the Early Life Plan cohort in Shanghai, China. High sensitivity C reactive protein, sex hormone binding globulin, insulin-like growth factor I, IGF binding protein 2 (IGFBP-2), total and high molecular weight adiponectin and glycosylated fibronectin concentrations were measured in serum samples at 11-14 weeks of gestation. Routine first-trimester blood test biomarkers included fasting plasma glucose (FPG), serum lipids and thyroid hormones. Five ML models [stepwise logistic regression, least absolute shrinkage and selection operator (LASSO), random forest, support vector machine and k-nearest neighbor] were employed to predict GDM. The study subjects were randomly split into two sets for model development (training set, n = 70 GDM/control pairs) and validation (testing set: n = 30 GDM/control pairs). Model performance was evaluated by the area under the curve (AUC) in receiver operating characteristics. RESULTS: FPG and IGFBP-2 were consistently selected as predictors of GDM in all ML models. The random forest model including FPG and IGFBP-2 performed the best (AUC 0.80, accuracy 0.72, sensitivity 0.87, specificity 0.57). Adding more predictors did not improve the discriminant power. CONCLUSION: The combination of FPG and IGFBP-2 at early gestation (11-14 weeks) could predict later development of GDM with moderate discriminant power. Further validation studies are warranted to assess the utility of this simple combination model in other independent cohorts.

Associations of Adipokine Levels With Levels of Remnant Cholesterol: The Multi-Ethnic Study of Atherosclerosis.

BACKGROUND: The metabolic syndrome phenotype of individuals with obesity is characterized by elevated levels of triglyceride-rich lipoproteins and remnant particles, which have been shown to be significantly atherogenic. Understanding the association between adipokines, endogenous hormones produced by adipose tissue, and remnant cholesterol (RC) would give insight into the link between obesity and atherosclerotic cardiovascular disease. METHODS AND RESULTS: We studied 1791 MESA (Multi-Ethnic Study of Atherosclerosis) participants who took part in an ancillary study on body composition with adipokine levels measured (leptin, adiponectin, and resistin) at either visit 2 or visit 3. RC was calculated as non-high-density lipoprotein cholesterol minus low-density lipoprotein cholesterol, measured at the same visit as the adipokines, as well as subsequent visits 4 through 6. Multivariable-adjusted linear mixed-effects models were used to assess the cross-sectional and longitudinal associations between adipokines and log-transformed levels of RC. Mean±SD age was 64.5±9.6 years; mean±SD body mass index was 29.9±5.0 kg/m2; and 52.0% were women. In fully adjusted cross-sectional models that included body mass index, diabetes, low-density lipoprotein cholesterol, and lipid-lowering therapy, for each 1-unit increment in adiponectin, there was 14.6% (95% CI, 12.2-16.9) lower RC. With each 1-unit increment in leptin and resistin, there was 4.8% (95% CI, 2.7-7.0) and 4.0% (95% CI, 0.2-8.1) higher RC, respectively. Lower adiponectin and higher leptin were also associated with longitudinal increases in RC levels over median follow-up of 5 (interquartile range, 4-8) years. CONCLUSIONS: Lower adiponectin and higher leptin levels were independently associated with higher levels of RC at baseline and longitudinal RC increase, even after accounting for body mass index and low-density lipoprotein cholesterol.

The effect of hydrogen gas on the oxidative stress response in adipose tissue.

Oxidative stress in adipose tissue may alter the secretion pattern of adipocytokines and potentially promote atherosclerosis. However, the therapeutic role of hydrogen in adipose tissue under oxidative stress remains unclear. In this study, subcutaneous adipose tissue (SCAT) was collected from the mid-thoracic wounds of 12 patients who underwent open-heart surgery with a mid-thoracic incision. The adipose tissue was then immersed in a culture medium dissolved with hydrogen, which was generated using a hydrogen-generating device. The weight of the adipose tissue was measured before and after hydrogenation, and the tissue was immunostained for nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and superoxide dismutase (SOD), which are markers of oxidative stress. The immunostaining results showed that HO-1 and Nrf2 expression levels were significantly decreased in the hydrogenated group, whereas SOD expression levels increased, but did not attain statistical significance. Image analysis of adipose tissue revealed that a reduction in adipocyte size. Furthermore, hydrogenated adipose tissue showed a trend toward increased gene expression levels of adiponectin and decreased gene expression levels of chemerin, an adipocytokine involved in adipogenesis. These results demonstrated the therapeutic potential of hydrogen gas for oxidative stress in adipose tissue and for reducing adipocyte size.

High-fat diet impact on prostate gland from adiponectin knockout mice: Morphometric, metabolic and inflammatory cytokines analyses.

AIMS: Obesity is a global public health issue, and some studies have linked it to an increased risk of prostatic diseases. This study aimed to evaluate the effects of a high-fat diet on metabolic parameters and prostate morphology in wild-type (WT) and adiponectin knockout (KO) mice. MAIN METHODS: Male WT and KO mice were fed a control diet (CD) or high-fat diet (HFD) for 6 months. Serum metabolic parameters, inflammatory cytokines in epididymal fat tissue, dorsal prostatic lobe morphometry and histopathology were analyzed. KEY FINDINGS: CD WT and CD KO mice did not exhibit altered metabolic or prostatic parameters. However, HFD WT mice showed altered glucose and insulin tolerance even without excessive weight gain. On the other hand, HFD KO mice developed obesity, with an increase in low-density lipoprotein (11.8 ± 5.1 vs. 31.4 ± 3.6 mg/dL), high-density lipoprotein (73.4 ± 7.4 vs. 103.4 ± 2.5 mg/dL), and total cholesterol levels (126.2 ± 16.1 vs. 294.6 ± 23.2 mg/dL), a decrease in insulin levels (28.7 ± 12.2 vs. 4.6 ± 2.3 µIU/mL), and glucose and insulin resistance. We also observed that HFD KO animals display an increase in inflammatory cytokines, such as IL6, IL1ß, and IL1RA. The dorsal prostate from HFD KO animals also presented significant increases in the mast cells (1.9 ± 0,7 vs. 5,3 ± 1.5 cells/field) and Ki67 index (2.91 ± 0.6 vs. 4.7 ± 0.4 %). SIGNIFICANCE: The above findings highlight the complex interactions between adiponectin, metabolism, malnutrition, and prostate health. Metabolic deregulation combined with adipose inflammation potentially induces a proliferative and inflammatory microenvironment in the prostate gland under conditions of low adiponectin production, potentially impairing prostate morphophysiology in the context of obesity and aging.

The association between macrosomia and glucose, lipids and hormones levels in maternal and cord serum: a case-control study.

BACKGROUND: The formation of macrosomia is associated with excessive nutrition and/or unable to regulate effectively. This case-control study aims to explore the relationship between macrosomia and glucose, lipids and hormones levels in maternal and cord serum. METHODS: In the case-control study, 78 pairs of mothers and newborns were recruited who received care at one hospital of Hebei, China between 2016 and 2019. According to the birth weight (BW) of newborns, participants were divided into macrosomia group (BW ≥ 4000 g, n = 39) and control group (BW between 2500 g and 3999 g, n = 39). Maternal vein blood and cord vein blood were collected and assayed. All data were compared between the two groups. Unconditional logistics regression analysis was used to test the relationship between macrosomia and glucose, lipids and hormones in maternal and cord serum. RESULTS: In maternal and cord serum, the levels of leptin, leptin/adiponectin ratio (LAR), glucose and triglyceride (TG) in macrosomia group were higher than those in control group, and the levels of high-density lipoprotein cholesterol (HDL-C) were lower. The percentage of maternal glucose and lipids transfer to cord blood did not differ between the two groups. High levels of TG in maternal serum were positively correlated with macrosomia, and high levels of LAR, TG and glucose in cord serum were positively correlated with macrosomia. CONCLUSION: In conclusion, the results of the current study, suggest that the nutrients and metabolism-related hormones in maternal and umbilical cord are closely related to macrosomia. During pregnancy, the nutritional status of pregnant women should be paid attention to and to obtain a good birth outcome.

Acetate attenuates hypothalamic pyroptosis in experimentally induced polycystic ovarian syndrome.

This study hypothesized that SCFA, acetate impacts positively on hypothalamic pyroptosis and its related abnormalities in experimentally induced PCOS rat model, possibly through NrF2/HIF1-α modulation. Eight-week-old female Wister rats were divided into groups (n = 5), namely control, PCOS, acetate and PCOS + acetate groups. Induction of PCOS was performed by administering 1 mg/kg body weight of letrozole for 21 days. After PCOS confirmation, the animals were treated with 200 mg/kg of acetate for 6 weeks. Rats with PCOS were characterized with insulin resistance, leptin resistance, increased plasma testosterone as well as degenerated ovarian follicles. There was also a significant increase in hypothalamic triglyceride level, triglyceride-glucose index, inflammatory biomarkers (SDF-1 and NF-kB) and caspase-6 as well as plasma LH and triglyceride. A decrease was observed in plasma adiponectin, GnRH, FSH, and hypothalamic GABA with severe inflammasome expression in PCOS rats. These were accompanied by decreased level of NrF2/HIF1-α, and the alterations were reversed when treated with acetate. Collectively, the present results suggest the therapeutic impact of acetate on hypothalamic pyroptosis and its related comorbidity in PCOS, a beneficial effect that is accompanied by modulation of NrF2/HIF1-α.

Adiponectin Resistance in Obesity: Adiponectin Leptin/Insulin Interaction.

The adiponectin (APN) levels in obesity are negatively correlated with chronic subclinical inflammation markers. The hypertrophic adipocytes cause obesity-linked insulin resistance and metabolic syndrome. Furthermore, macrophage polarization is a key determinant regulating adiponectin receptor (AdipoR1/R2) expression and differential adiponectin-mediated macrophage inflammatory responses in obese individuals. In addition to decrease in adiponectin concentrations, the decline in AdipoR1/R2 messenger ribonucleic acid (mRNA) expression leads to a decrement in adiponectin binding to cell membrane, and this turns into attenuation in the adiponectin effects. This is defined as APN resistance, and it is linked with insulin resistance in high-fat diet-fed subjects. The insulin-resistant group has a significantly higher leptin-to-APN ratio. The leptin-to-APN ratio is more than twofold higher in obese individuals. An increase in expression of AdipoRs restores insulin sensitivity and ß-oxidation of fatty acids via triggering intracellular signal cascades. The ratio of high molecular weight to total APN is defined as the APN sensitivity index (ASI). This index is correlated to insulin sensitivity. Homeostasis model of assessment (HOMA)-APN and HOMA-estimated insulin resistance (HOMA-IR) are the most suitable methods to estimate the metabolic risk in metabolic syndrome. While morbidly obese patients display a significantly higher plasma leptin and soluble (s)E-selectin concentrations, leptin-to-APN ratio, there is a significant negative correlation between leptin-to-APN ratio and sP-selectin in obese patients. When comparing the metabolic dysregulated obese group with the metabolically healthy obese group, postprandial triglyceride clearance, insulin resistance, and leptin resistance are significantly delayed following the oral fat tolerance test in the first group. A neuropeptide, Spexin (SPX), is positively correlated with the quantitative insulin sensitivity check index (QUICKI) and APN. APN resistance together with insulin resistance forms a vicious cycle. Despite normal or high APN levels, an impaired post-receptor signaling due to adaptor protein-containing pleckstrin homology domain, phosphotyrosine-binding domain, and leucine zipper motif 1 (APPL1)/APPL2 may alter APN efficiency and activity. However, APPL2 blocks adiponectin signaling through AdipoR1 and AdipoR2 because of the competitive inhibition of APPL1. APPL1, the intracellular binding partner of AdipoRs, is also an important mediator of adiponectin-dependent insulin sensitization. The elevated adiponectin levels with adiponectin resistance are compensatory responses in the condition of an unusual discordance between insulin resistance and APN unresponsiveness. Hypothalamic recombinant adeno-associated virus (rAAV)-leptin (Lep) gene therapy reduces serum APN levels, and it is a more efficient strategy for long-term weight maintenance.

Study of adiponectin gene (rs1501299) polymorphism and serum adiponectin level in patients with primary knee osteoarthritis.

BACKGROUND: We aimed to study, for the first time in the Egyptian population, the relationship between the serum adiponectin level in knee osteoarthritis (KOA) patients and its correlation with clinical, radiological, and ultrasonographic characteristics. Additionally, investigate the relationship between the adiponectin (ADIPOQ) gene rs1501299 (+ 276G/T) polymorphism and KOA susceptibility and severity. METHODS: This case-control study enrolled 40 patients with primary KOA and 40 matched controls. All patients underwent physical examination of the knee, pain assessment using the visual analogue scale (VAS), and functional evaluation by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Severity of KOA was assessed by Kellgren Lawrence (KL) grading scale and ultrasonography grading systems. Serum adiponectin levels and adiponectin (ADIPOQ) gene single nucleotide polymorphism (SNP) (rs1501299) genotyping were done for all patients and controls. RESULTS: The study included 40 patients with primary symptomatic KOA and 40 controls with comparable age, sex, and body mass index. The genotype of the rs1501299 (+ 276G/T) polymorphism of the ADIPOQ gene was determined using TaqMan allelic discrimination. An enzyme-linked immunosorbent test was used to measure the level of serum adiponectin. The Western Ontario and McMaster Universities Osteoarthritis (WOMAC) score was used to assess functional capability, while the visual analogue scale was utilised to assess knee pain. Using the Kellgren-Lawrence (KL) grading method and global femoral cartilage (GFC) ultrasound grading, the severity of KOA was assessed. No significant differences between patients and controls as regards the genotype distributions and allele frequencies (p = 0.400, p = 0.507, respectively) of ADIPOQ gene rs1501299 (+ 276G/T) polymorphism. Furthermore, serum adiponectin level was significantly higher in the patients compared to healthy subjects (p < 0.001). Additionally, adiponectin level had a significant negative correlation with disease severity as evaluated by KL and GFC grading (r=-0.351, p = 0.027 and r=-0.397, p = 0.011, respectively). CONCLUSIONS: The ADIPOQ gene rs1501299 (+ 276G/T) polymorphism was not associated with KOA severity or vulnerability. The level of adiponectin considerably reduced as the severity of KOA rose, indicating that adiponectin may have a preventive effect in KOA.

The effects of nonsoy legumes consumption on serum levels of inflammatory biomarkers and Adiponectin in overweight/obese adults: A systematic review and meta-analysis of randomized controlled trials.

Nonsoy legumes offer many health benefits, including improved arterial function, reduced cholesterol levels, and better management of cardiovascular diseases and type 2 diabetes. This systematic review and meta-analysis aim to clarify the inconclusive findings from randomized controlled trials (RCTs) by comprehensively evaluating the effects of nonsoy legumes consumption on serum levels of inflammatory biomarkers and Adiponectin. The search encompassed databases up to January 2024, including PubMed, EMBASE, MEDLINE, Scopus, Web of Science, and Cochrane CENTRAL to retrieve all RCTs examining the effects of nonsoy legumes on inflammatory biomarkers or Adiponectin. The effect sizes quantified as mean differences (MD) and standard deviations (SD) of outcomes, and an overall effect estimate was derived using a random-effects model. RCTs examining serum levels of C-reactive protein (CRP), Interleukin-6 (IL-6), Tumor Necrosis Factor-alpha (TNF-α), Interleukin-1ß (IL-1ß), and Adiponectin were included in the final meta-analysis. Results revealed that consumption of nonsoy legumes increased Adiponectin serum levels (P=.0017) and reduced IL-1ß serum levels (P<.0001). However, it may not significantly affect CRP (P=.2951), IL-6 (P=.2286), and TNF-α (P=.6661) levels. Subgroup analyses showed that nonsoy legumes consumption significantly decreased TNF-α serum levels in studies involving healthy participants. Additionally, sensitivity analysis using the leave-one-out method suggested a potential significant reduction in serum levels of IL-6. This study indicates that consuming nonsoy legumes can increase levels of Adiponectin and decrease serum levels of IL-1ß in overweight or obese adults.

The role of AdipoQ on proliferation, apoptosis, and hormone Secretion in chicken primary adenohypophysis cells.

Adiponectin (AdipoQ), an adipokine secreted by adipocytes, has been reported to exist widely in various cell types and tissues, including the adenohypophysis of chickens. However, the molecular mechanism by which AdipoQ regulates the function of chicken adenohypophysis remains elusive. In this study, we investigated the effects of AdipoQ on proliferation, apoptosis, secretion of related hormones (FSH, LH, TSH, GH, PRL and ACTH) and expression of related genes (FSHß, LHß, GnRHR, TSHß, GH, PRL and ACTH) in primary adenohypophysis cells of chickens by using real-time fluorescent quantitative PCR (RT-qPCR), cell counting kit-8 (CCK-8), flow cytometry, enzyme-linked immunosorbent assay (ELISA) and Western blot (WB) assays. Our results showed that AdipoQ promoted the proliferation of chicken primary adenohypophysis cells, up-regulated the mRNA expression of proliferation-related genes CDK1, PCNA, CCND1 and P21 (P < 0.05), as well as the increased protein expression of CDK1 and PCNA (P < 0.05). Furthermore, AdipoQ inhibited apoptosis of chicken primary adenohypophysis cells, resulting in down-regulation of pro-apoptotic genes Caspase3, Fas, and FasL mRNA expression, and decreased Caspase3 protein expression (P < 0.05). Moreover, there was an up-regulation of anti-apoptotic gene Bcl2 mRNA and protein expression (P < 0.05). Additionally, AdipoQ suppressed the secretion of FSH, LH, TSH, GH, PRL, and ACTH (P < 0.05), as well as the mRNA expression levels of related genes (P < 0.05). Treatment with AdipoRon (a synthetic substitute for AdipoQ) and co-treatment with RNA interference targeting AdipoQ receptors 1/2 (AdipoR1/2) had no effect on the secretion of FSH, LH, TSH, GH, PRL, and ACTH, as well as the mRNA expression levels of the related genes. This suggests that AdipoQ's regulation of hormone secretion and related gene expression is mediated by the AdipoR1/2 signaling axis. Importantly, we further demonstrated that the mechanism of AdipoQ on FSH, LH, TSH and GH secretion is realized through AMPK signaling pathway. In conclusion, we have revealed, for the first time the molecular mechanism by which AdipoQ regulates hormone secretion in chicken primary adenohypophysis cells.

N-terminal pro-B-type natriuretic peptide levels vary by ethnicity and are associated with insulin sensitivity after gestational diabetes mellitus.

BACKGROUND: Individuals of South Asian origin have a greater risk of cardiovascular disease after gestational diabetes mellitus (GDM) than European individuals. B-type natriuretic peptide (BNP) and the amino-terminal fragment of its prohormone (NT-proBNP) are commonly used for heart failure screening and diagnosis, but biologically BNP exerts several beneficial cardiovascular effects primarily by counteracting the renin-angiotensin-aldosterone-system. We asked whether ethnic differences in circulating NT-proBNP levels could be explained by the differences in cardiometabolic and inflammatory risk markers? METHODS: We examined 162 South Asian and 107 Nordic women in Norway 1-3 years after GDM with a clinical examination, fasting blood samples and an oral glucose tolerance test. We measured the levels of NT-proBNP, high-sensitivity cardiac troponin T, high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), leptin, adiponectin and markers of insulin sensitivity, such as the Matsuda insulin sensitivity index (ISI). Finally, we tried to identify which independent covariate best mediated the ethnic differences in NT-proBNP. RESULTS: The mean (SD) age was 35.3 (4.5) years, BMI 29.1 (6.0) kg/m2, waist-height ratio 0.60 (0.08) and 164 women (61%) had prediabetes/diabetes. Notably, South Asian women had lower levels of NT-proBNP than Nordic women in both the normoglycemic and prediabetes/diabetes groups (median (IQR) 26  (15-38)  vs. 42 (22-66) ng/L, p < 0.001). Higher NT-proBNP levels were associated with greater insulin sensitivity in both South Asian and Nordic women (p = 0.005 and p < 0.001). South Asian women had higher levels of hsCRP (median (IQR) 2.2 (1.1-4.4) vs. 1.2 (0.3-4.2) mg/L), IL-6 (2.3 (1.5-3.2) vs. 1.5 (1.5-2.5) pg/mL), leptin (1647 (1176-2480) vs. 1223 (876-2313) pmol/L), and lower adiponectin levels (7.2 (5.3-9.3) vs. 10.0 (7.2-13.5) mg/L) and Matsuda ISI (2.4 (1.7-3.7) vs. 4.2 (2.9-6.1), pall<0.01) than Nordic women. Even after adjusting for these differences, higher NT-proBNP levels remained associated with insulin sensitivity (22% higher NT-proBNP per SD Matsuda ISI, p = 0.015). Insulin sensitivity and adiponectin mediated 53% and 41% of the ethnic difference in NT-proBNP. CONCLUSIONS: NT-proBNP levels are lower in South Asian than in Nordic women after GDM. Lower NT-proBNP levels correlate with impaired insulin sensitivity. Lower NT-proBNP levels in South Asian women could, therefore, be attributed to impaired insulin sensitivity rather than total body fat.

Adipocyte endothelin B receptor activation inhibits adiponectin production and causes insulin resistance in obese mice.

AIMS: Endothelin-1 (ET-1) is elevated in patients with obesity and adipose tissue of obese mice fed high-fat diet (HFD); however, its contribution to the pathophysiology of obesity is not fully understood. Genetic loss of endothelin type B receptors (ETB) improves insulin sensitivity in rats and leads to increased circulating adiponectin, suggesting that ETB activation on adipocytes may contribute to obesity pathophysiology. We hypothesized that elevated ET-1 in obesity promotes insulin resistance by reducing the secretion of insulin sensitizing adipokines, via ETB receptor. METHODS: Male adipocyte-specific ETB receptor knockout (adETBKO), overexpression (adETBOX), or control littermates were fed either normal diet (NMD) or high-fat diet (HFD) for 8 weeks. RESULTS: RNA-sequencing of epididymal adipose (eWAT) indicated differential expression of over 5500 genes (p < 0.05) in HFD compared to NMD controls, and changes in 1077 of these genes were attenuated in HFD adETBKO mice. KEGG analysis indicated significant increase in metabolic signaling pathway. HFD adETBKO mice had significantly improved glucose and insulin tolerance compared to HFD control. In addition, adETBKO attenuated changes in plasma adiponectin, insulin, and leptin that is observed in HFD versus NMD control mice. Treatment of primary adipocytes with ET-1 caused a reduction in adiponectin production that was attenuated in cells pretreated with an ETB antagonist. CONCLUSION: These data indicate elevated ET-1 in adipose tissue of mice fed HFD inhibits adiponectin production and causes insulin resistance through activation of the ETB receptor on adipocytes.

Metabolic responses to albumin deficiency differ distinctly between partial and full ablation of albumin expression in mice.

It had been observed that homozygous albumin knockout mice (Alb-/-) exhibit low plasma free fatty acid (FFA) concentration and improved blood glucose regulation. However, it was not yet known to what extent heterozygous albumin knockout (Alb+/-) mice would display a similar phenotype. Alb-/-, Alb+/-, and wild-type (WT) female mice were studied on a low-fat diet (LFD) or high-fat diet (HFD). On both diets, decreased plasma FFA concentration, and improved glucose tolerance test were observed in Alb-/-, but not in Alb+/-, compared to WT. Plasma adiponectin concentration showed greater elevation in Alb-/- than Alb+/-. Consistent with that, adiponectin gene expression was significantly higher in Alb-/- mice than in Alb+/- and WT mice. A dose-dependent response was observed for hepatic Acadl gene expression showing higher Acadl gene expression in Alb-/- mice than in Alb+/- and WT mice. In conclusion, although female Alb+/- mice exhibited some slight differences from WT mice (e.g., increased plasma adiponectin and hepatic Acadl gene expression), Alb+/- mice did not exhibit improved glucoregulation in comparison to WT mice, indicating that a minor suppression of albumin expression is not sufficient to improve glucoregulation. Furthermore, it is now clear that although the response of female mice to HFD might be unique from how males generally respond, still the complete albumin deficiency in Alb-/- mice and the associated FFA reduction is capable of improving glucoregulation in females on this diet. The present results have implications for the role of albumin and FFA in the regulation of metabolism.

The Association between ADIPOQ Gene Polymorphisms and Diabetic Retinopathy Risk: A Systematic Review and Meta-Analysis.

Background and Objectives: Recent studies have focused on the association between the risk of diabetic retinopathy (DR) and the rs1501299 and rs2241766 polymorphisms of the ADIPOQ gene; however, their results remain inconclusive. Thus, a systematic review and meta-analysis were carried out to clarify the role of these polymorphisms in the development of DR. Materials and Methods: A systematic search of electronic databases (PubMed, Scopus, and Cochrane Library) was conducted until 25 June 2024, and a reference list of relevant articles was collected, which explored the association between the rs1501299 and rs2241766 polymorphisms of the ADIPOQ gene and the risk of DR. The pooled odds ratios (OR) and 95% confidence intervals (CI) were estimated via random-effects model, and the meta-analysis was implemented by using Review Manager 5.4. Results: In total, 6 out of 182 studies, with 1888 cases (DR) and 2285 controls (without DR), were included in the meta-analysis. A statistically significant association between the rs1501299 polymorphism and the DR risk was recorded in G vs. T in the overall analysis (OR = 0.84, 95% CI = 0.72-0.99, p = <0.05, I2 = 23%, n = 5 studies). Additionally, the summary results in the subgroup analysis according to the control type were as follows: the DR versus diabetes mellitus (DM) control type revealed a statistically significant association in G vs. T: OR = 0.81, 95% CI = 0.67-0.97, p = <0.05, I2 = 27%, n = 4 studies; GG vs. GT: OR = 0.72, 95% CI = 0.53-0.98, p = <0.05, I2 = 49%, n = 4 studies; GG vs. (GT + TT): OR = 0.73, 95% CI = 0.55-0.96, p = <0.05, I2 = 44%, n = 4 studies. No significant association was observed between the rs2241766 polymorphism and the DR risk. Conclusions: The current meta-analysis supports the association between the rs1501299 polymorphism of the ADIPOQ gene and the DR risk in patients with DM.

Periorbital melanosis and its possible association with insulin resistance and vitamin D deficiency: A pilot case-control study.

OBJECTIVE: To investigate the possible association of periorbital melanosis (POM) with insulin resistance (IR) and vitamin D serum levels. METHODS: In this pilot, case-control study, we included 100 adult patients with POM and 100 age- and sex-matched healthy control subjects. Vitamin D levels and IR indices (i.e., homeostatic model assessment-insulin resistance [HOMA-IR], triglycerides/high-density lipoprotein cholesterol (TG/HDL-c) ratio, adiponectin/leptin (A/L) ratio) were compared between cases and controls. RESULTS: Compared with controls, POM cases had significantly higher values of HOMA-IR and TG/HDL-c ratio, and significantly lower values of A/L and vitamin D. HOMA-IR and TG/HDL-c ratio were statistically significantly positively correlated with POM severity while Vitamin D and A/L ratio were statistically significantly negatively correlated. CONCLUSION: POM was associated with indices of IR and vitamin D deficiency. However, the exact causal link among POM, IR, and vitamin D needs to be established. However, the results of this pilot study suggest that POM may have potential as a cutaneous non-invasive marker of these metabolic disorders which would assist in detecting and treating them at an early stage.

Overview of a novel osmotin abolishes abnormal metabolic-associated adiponectin mechanism in Alzheimer's disease: Peripheral and CNS insights.

Alzheimer's disease (AD) is a degenerative brain disease that affects millions of people worldwide. It is caused by abnormalities in cholinergic neurons, oxidative stress, and inflammatory cascades. The illness is accompanied by personality changes, memory issues, and dementia. Metabolic signaling pathways help with fundamental processes like DNA replication and RNA transcription. Being adaptable is essential for both surviving and treating illness. The body's metabolic signaling depends on adipokines, including adiponectin (APN) and other adipokines secreted by adipose tissues. Energy homeostasis is balanced by adipokines, and nutrients. Overconsumption of nutrients messes with irregular signaling of adipokines, such as APN in both peripheral and brain which leads to neurodegeneration, such as AD. Despite the failure of traditional treatments like memantine and cholinesterase inhibitors, natural plant bioactive substances like Osmotin (OSM) have been given a focus as potential therapeutics due to their antioxidant properties, better blood brain barrier (BBB) permeability, excellent cell viability, and especially nanoparticle approaches. The review highlights the published preclinical literature regarding the role of OSM in AD pathology while there is a need for more research to investigate the hidden therapeutic potential of OSM which may open a new gateway and further strengthen its healing role in the pathogenesis of neurodegeneration, especially AD.

Plasma C-reactive protein is associated with a pro-inflammatory and adverse plaque phenotype.

BACKGROUND AND AIMS: Systemic low-grade inflammation, measured by plasma high-sensitivity C-reactive protein (hsCRP) levels, is an important risk factor for atherosclerotic cardiovascular disease (ASCVD). To date, however, it is unknown whether plasma hsCRP is associated with adverse histological plaque features. METHODS: Plaques were derived during carotid endarterectomy. Patients with hsCRP levels ≥2 mg/L were evaluated for pro-inflammatory and adverse plaque characteristics, as well as future ASCVD events, and compared with patients with low hsCRP levels. Logistic and linear regression analyses in addition to subdistribution hazard ratios were conducted, adjusted for cardiovascular risk factors. RESULTS: A total of 1096 patients were included, of which 494 (46.2 %) had hsCRP levels ≥2 mg/L. Elevated hsCRP levels 2 mg/L were independently associated with levels of plaque interleukin 6, beta coefficient of 109.8 (95 % confidence interval (CI): 33.4, 186.5; p = 0.005) pg/L, interleukin 8 levels, 194.8 (110.4, 378.2; p = 0.03) pg/L and adiponectin plaque levels, -16.8 (-30.1, -3.6; p = 0.01) µg/L, compared with plaques from patients with low hsCRP levels. Histological analysis revealed increased vessel density in high hsCRP patients, odds ratio (OR) of 1.57 (1.20, 2.09; p = 0.001), larger lipid core, 1.35 (1.02, 1.73; p = 0.04), and increased macrophage content, 1.32 (1.02, 1.73; p = 0.04). Over a 3-year follow-up period, hsCRP levels ≥2 mg/L were associated with a hazard ratio of 1.81 (1.03, 3.16; p = 0.04) for coronary artery disease event risk. CONCLUSIONS: The distinct inflammatory and histological features observed in carotid plaques among individuals with hsCRP levels ≥2 mg/L underscore the utility of plasma hsCRP as a potent identifier for patients harboring high-risk plaques.