Mediatory effect of circulating vaspin on resting metabolic rate in obese individuals

Association of Serum Vaspin Concentration with Metabolic Disorders in Obese Individuals

Vaspin, a molecule produced in visceral adipose tissue, seems to participate in the pathogenesis of metabolic disorders. The study aimed to determine the association of vaspin concentration with metabolic disorders in obese individuals. Forty obese patients and twenty normal-weight subjects underwent biochemical (fasting glucose, insulin, lipid profile, interleukin-6, hs-CRP, vaspin concentration), blood pressure, and anthropometric measurements. The HOMA-IR index was calculated. Serum vaspin concentrations in the obese group were significantly higher than in the control group (0.82 ± 0.62 vs. 0.43 ± 0.59; p < 0.001). Among the entire population, vaspin concentration was positively correlated with body weight, BMI, WHR, and the percentage and mass of adipose tissue. Positive correlations between vaspin concentration and triglyceride level, insulin concentration, and HOMA-IR value were found. Vaspin concentration was positively correlated with hs-CRP and IL-6 levels. In obese patients, positive correlations between vaspin concentration and the percentage of adipose tissue and hs-CRP level were demonstrated. Logistic regression analysis showed that increased BMI was the biggest factor stimulating vaspin concentrations (OR = 8.5; 95% CI: 1.18–61.35; p = 0.0338). An elevated vaspin level may imply its compensatory role against metabolic disorders in obese patients. Thus, vaspin appears to be a useful diagnostic parameter for new therapeutic approaches in obesity-related complications. Nevertheless, due to the small sample size, further studies are needed to confirm our results.

Vitamin D insufficiency and its association with adipokines and atherogenic indices in patients with metabolic syndrome: A case-control study

INTRODUCTION

Vitamin D deficiency is one of the most common nutritional disorders in most countries of the world. The present study was designed and implemented with the aim of investigating the relationship between vitamin D deficiency and the level of adipokines, atherogenesis indicators and factors related to metabolic syndrome.

METHODS

This case-control study was done on 195 patients with metabolic syndrome aged 20-50 y who attended the health centers in Zabol County, northeast Iran, between April 2021 and January 2022. Anthropometric and biochemical parameters were measured for all subjects with standard methods. To determine serum 25(OH)D levels, we used enzymatic linked immunosorbent assay (ELISA) kits. Atherogenic index of plasma (AIP) was calculated as log (TG/HDL-c). The visceral adiposity index (VAI) and the lipid accumulation product (LAP) were estimated according to standard formulas.

RESULTS AND DISCUSSION

Participants in the case group had lower serum levels of 25(OH)D compared to controls (19.8 ± 6.2 ng/ml vs. 41.2 ± 9.7ng/ml, P<0.001). We found that the mean serum levels of fasting blood sugar (P=0.023) and TG (P=0.008) as well as HOMA-IR (P=0.023) were significantly higher in the cases compared to controls. Also, patients with MetS and vitamin D insufficiency (cases) had higher AIP (P=0.040) and LAP (P=0.012) than controls. Furthermore, serum 25(OH)D levels showed significant inverse correlations with serum RBP-4 and a positive correlation with serum omentin-1 concentrations. The results of the present study showed that vitamin D deficiency correlated with some of the cardiometabolic risk factors among the patients with MetS.

The relationship between dietary phytochemical index and resting metabolic rate mediated by inflammatory factors in overweight and obese women: a cross-sectional study

Background

Unhealthy dietary patterns are the most important modifiable risk factors for obesity and overweight. This study aimed to examine the relationship between Dietary Phytochemical Index (DPI) and resting metabolic rate (RMR), mediated by inflammatory factors, in overweight and obese women.

Methods

A total of 404 women, aged 18–48 years, were included in the cross-sectional study. DPI was calculated using the 147-item food frequency questionnaire (FFQ). Anthropometric measurements, RMR, and blood biomarkers were assessed using standard protocols.

Results

There was marginally significant association between adherence to DPI and RMR status in the crude model (OR = 1.41, 95% CI 0.94–2.11, P = 0.09). After adjusting for potential confounders, a significant association was seen between the DPI and increase RMR.per.kg (OR = 2.77, 95% CI 0.98–7.82, P = 0.05). Our results indicated that plasminogen activator inhibitor-1 (PAI-1), transforming growth factor (TGF-β), and monocyte chemoattractant protein-1 (MCP-1) had a mediatory effect on the association between RMR and DPI (P > 0.05). Indeed, it was shown that, PAI-1, TGF-β, and MCP-1 destroyed the significance of this association and could be considered as mediating markers. However, no mediating effect was observed for high-sensitivity C reactive protein (hs-CRP).

Conclusions

Adherence to DPI can improve the RMR by reducing levels of inflammatory markers, and may be considered as a treatment for obesity. However, more long-term studies are recommended.

The healthy/unhealthy dietary pattern is associated with resting metabolic rate status among women with overweight/obesity

BACKGROUND

Although various dietary patterns have been indicated to be associated with the resting metabolic rate [RMR], limited data are available in this field. This study was therefore focused on the association between dietary patterns and resting metabolic rate among participants with overweight and obesity.

METHODS

This cross-sectional study was conducted on 304 women with overweight or obesity (BMI ≥ 25 kg/m²), aged 18-50. Anthropometric assessments, physical activity and biochemical measurements were assessed. RMR was also measured by means of indirect calorimetry. Dietary intake of participants was evaluated by 147-item semi-quantitative food frequency questionnaire [FFQ].

RESULTS

There was a significant association between higher adherence to the healthy dietary pattern [HDP] and RMR (P = 0.05), intakes of protein (P = 0.003), minerals (P = 0.001) as well as fat free mass [FFM] (P = 0.002), bone mineral content (P = 0.001), skeletal muscle mass (P = 0.001), soft lean mass (P = 0.002) and visceral fat area (P = 0.05). Also, there was a considerable association between higher adherence to the unhealthy dietary pattern [UHDP] and fasting blood sugar [FBS] (P = 0.05). Using multinomial logistic regression has been shown that the medium adherence to the HDP was marginally significant with decreased resting metabolic rate [Dec. RMR] group in crude model (OR: 0.54; 95% CI: 0.28-1.05, P = 0.07). After controlling for various confounders such as age, FFM, physical activity, and energy intake, the association between Dec. RMR group and the lowest quartile of the HDP (OR: 0.36; 95% CI: 0.14-0.91, P = 0.03) became significant as well as the association between Dec. RMR group and medium adherence to the HDP (OR: 0.42; 95% CI: 0.18-0.97, P = 0.04). The medium adherence to the UHDP in crude model was also significant with increased resting metabolic rate [Inc. RMR] group (OR: 2.59; 95% CI: 1.01-6.65, P = 0.04).

CONCLUSIONS

Our study showed that there are significant associations between dietary patterns and RMR status.

The Association Between Low Carbohydrate Diet and Resting Metabolic Rate in Overweight and Obese Women: A Cross-Sectional Study

Resting metabolic rate (RMR) accounts for most daily energy expenditure. The low carbohydrate diet (LCD) attenuates decreases in RMR. This study aims to investigate the relationship between an LCD and RMR status among overweight and obese women. We enrolled 291 overweight and obese women in this cross-sectional study. Body mass index (BMI), fat mass, fat-free mass, visceral fat, and insulin level were assessed. RMR was measured using indirect calorimetry. LCD score (LCDS) was measured using a validated semi-quantitative food frequency questionnaire. Analysis of variance, independent sample t-test, and Multinomial logistic regression tests were used. Results showed no relationship between LCDS and deviation of normal RMR (DNR) even after adjust for confounders (increased [Inc.] RMR: odds ratio [OR], 0.97; 95% confidence interval [CI], 0.92–1.01; p = 0.20; decreased [Dec.] RMR: OR, 0.97; 95% CI, 0.94–1.00; p = 0.14). Some components of LCDS had no significant association with DNR, such as carbohydrate and Dec. RMR in adjusted model (OR, 1.62; 95% CI, 0.98–1.37; p = 0.08) and monounsaturated fatty acids and Dec. RMR in adjusted model (OR, 0.48; 95% CI, 0.21–1.10, p = 0.08). However, refined grains had a significant association with Inc. RMR in crude model (OR, 0.87; 95% CI, 0.77–0.99, p = 0.04). There is no association between LCDS and RMR status.

Ultra-processed food consumption and adult obesity risk: a systematic review and dose-response meta-analysis

We performed this systematic review and meta-analysis to evaluate observational studies assessing the association between ultra-processed food (UPF) consumption and the risk of overweight, obesity, and abdominal obesity in the general population. We searched the databases PubMed/MEDLINE, Scopus, Embase, and ISI Web of Science from inception until December 2020. Data were extracted from 12 studies (nine cross-sectional and three cohort studies). Odds ratio (OR) were pooled using a random-effects model. UPF consumption was associated with an increased risk of obesity (OR = 1.55; 95% CI: 1.36, 1.77; I² = 55%), overweight (OR = 1.36; 95% CI: 1.14, 1.63; I² = 73%), and abdominal obesity (OR = 1.41; 95% CI: 1.18, 1.68; I² = 62%). Furthermore, every 10% increase of UPF consumption in daily calorie intake was associated with a 7%, a 6%, and a 5% higher risk of overweight, obesity, and abdominal obesity, respectively. Dose-response meta-analysis of cross-sectional studies showed a positive linear association between UPF consumption and abdominal obesity. There was also a positive linear association between UPF consumption and risk of overweight/obesity in the analysis of cross-sectional studies and a positive monotonic association in the analysis of cohort studies. Our study suggests that UPF consumption is associated with an increased risk of excess weight or abdominal obesity.

Associations of dietary fats intake and adipokines levels in obese women

AIM

RBP4, Vaspin and omentin-1 are adipokines, which play an important role in the development of obesity-related complications. The main aim of this study was to investigate the effects of different kinds of fat intake on adipokine levels in obese women.

METHODS

A total of 272 obese women (BMI ≥ 30) were included in the current cross-sectional study, according to the inclusion and exclusion criteria. Body composition was measured using a body composition analyzer. For the measurement of retinol binding protein 4 (RBP4), vaspin and omentin-1 serum concentrations, an enzyme-linked immunosorbent assay (ELISA) method was used. Dietary intake was assessed using a 3-day 24-h dietary recall.

RESULTS

Statistically significant differences were found between polyunsaturated fatty acid (PUFAs) and linoleic acid intake and vaspin and omentin-1 levels. In addition, there were found statistically significant relationships between cholesterol, monounsaturated fatty acid (MUFAs) and total fat intakes with omentin-1 levels. Also, RBP4 and vaspin levels were different significant with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) intake. Moreover, the results revealed that there were statistically significant differences between RBP4 levels and α-linolenic acid and oleic acid intake.

CONCLUSION

This study revealed that by examining RBP4, vaspin and omentin-1 as adipokines, a novel link between fat intakes and adipokine levels was found.

The effects of supplementation with Cynara scolymus L. on anthropometric indices: А systematic review and dose-response meta-analysis of clinical trials

BACKGROUND

Studies on the efficacy of artichoke administration on anthropometric indices gave different outcomes. Hence, a systematic review and dose-response meta-analysis were accomplished to understand the effects of artichoke administration on anthropometric indices.

METHODS

Related clinical trials were found by searching in PubMed, Embase, the Cochrane Library and Scopus databases up to 29 February 2020. Weighted Mean Differences (WMD) were analyzed using a random-effects model. Heterogeneity, publication bias and sensitivity analysis were assessed for anthropometric indices.

RESULTS

Pooled analysis of 10 randomized controlled trials (RCTs) suggested that the artichoke administration has effect on waist circumference (WMD: -1.11 cm, 95 % CI: -2.08 to - 0.14), as opposed to the other anthropometric indices including weight (WMD: -0.62 kg, 95 % CI: -1.86 to 0.61) or BMI (WMD: -0.12, 95 % CI: -0.43 to 0.20). However, the analysis of the subgroups according to the health status showed that artichoke supplementation in hypertensive patients significantly reduced weight (WMD: -2.34 kg, 95 % CI: -3.11 to -1.57) but not the other indicators (WMD: -0.06 kg, 95 % CI: 0.78 to 0.67).

CONCLUSIONS

The artichoke supplementation has effect on the waist circumference, but not on the other anthropometric indices. For establishment of more accurate conclusion more studies with longer administration duration are need to be done.

The Relationship between Food Insecurity and Risk of Overweight or Obesity in under 18 Years Individuals: A Systematic Review and Meta-Analysis

OBJECTIVE

Food insecurit (FI) has been considered as reason for childhood and adolescent overweight/obesity (OW/OB). Hence, this study was undertaken to assess these relationships.

DESIGN

Related articles were found by searching the Web of Science, Scopus, PubMed and Embase databases until October 2019. Odds ratio (OR) was analized by a random-effects model. Standard methods were used for assessment of heterogeneity and publication bias. Data were available from 32 studies. The risk ratios of 139,762 participants were pooled from these articles for the meta-analysis.

RESULTS

This study domenstrated that children and adolescents in food-insecure condition are not at risk of OW/OB (OR = 1.02 95% CI: 0.99, 1.05). However, subgroup analysis indicated that FI related with inhanced risk of OW/OB in adolescents living in developed countries (OR = 1.14; 95% CI: 1.02, 1.27). Other subgroup analysis indicated that severe FI increased the risk of OW/OB among adolescents (OR = 1.24 95% CI: 1.03-1.49). In addition, we found that lower economic development significantly decreased risk of OW/OB among under 6 year children (OR = 0.88; 95% CI: 0.84, 0.93).

CONCLUSIONS

Our results showed that higher FI degrees were related with more risks of OW/OB among adolescents (12-18 years). Moreover, the country economic levels had effect on the association between FI and risk of OW/OB.

The Usefulness of Diagnostic Panels Based on Circulating Adipocytokines/Regulatory Peptides, Renal Function Tests, Insulin Resistance Indicators and Lipid-Carbohydrate Metabolism Parameters in Diagnosis and Prognosis of Type 2 Diabetes Mellitus with Obesity

The quantitative analysis of selected regulatory molecules, i.e., adropin, irisin, and vaspin in the plasma of obese patients with newly diagnosed, untreated type 2 diabetes mellitus, and in the same patients after six months of using metformin, in relation to adropinemia, irisinemia and vaspinemia in obese individuals, was performed. The relationship between plasma concentration of the adipocytokines/regulatory peptides and parameters of renal function (albumin/creatinine ratio-ACR, estimated glomerular filtration rate-eGFR), values of insulin resistance indicators (Homeostatic Model Assessment of Insulin Resistance (HOMA-IR2), Homeostatic Model Assessment of Insulin Sensitivity (HOMA-S), Homeostatic Model Assessment of β-cell function (HOMA-B), quantitative insulin sensitivity check index (QUICKI), insulin), and parameters of carbohydrate-lipid metabolism (fasting plasma glucose-FPG, glycated hemoglobin-HbA_1C, estimated glucose disposal rate-eGDR, fasting lipid profile, TG/HDL ratio) in obese type 2 diabetic patients was also investigated. Circulating irisin and vaspin were found significantly different in subjects with metabolically healthy obesity and in type 2 diabetic patients. Significant increases in blood levels of both analyzed adipokines/regulatory peptides were observed in diabetic patients after six months of metformin treatment, as compared to pre-treatment levels. The change in plasma vaspin level in response to metformin therapy was parallel with the improving of insulin resistance/sensitivity parameters. An attempt was made to identify a set of biochemical tests that would vary greatly in obese non-diabetic subjects and obese patients with type 2 diabetes, as well as a set of parameters that are changing in patients with type 2 diabetes under the influence of six months metformin therapy, and thus differentiating patients' metabolic state before and after treatment. For these data analyses, both statistical measures of strength of the relationships of individual parameters, as well as multidimensional methods, including discriminant analysis and multifactorial analysis derived from machine learning methods, were used. Adropin, irisin, and vaspin were found as promising regulatory molecules, which may turn out to be useful indicators in the early detection of T2DM and differentiating the obesity phenotype with normal metabolic profile from T2DM obese patients. Multifactorial discriminant analysis revealed that irisin and vaspin plasma levels contribute clinically relevant information concerning the effectiveness of metformin treatment in T2D patients. Among the sets of variables differentiating with the highest accuracy the metabolic state of patients before and after six-month metformin treatment, were: (1) vaspin, HbA1c, HDL, LDL, TG, insulin, and HOMA-B (ACC = 88 [%]); (2) vaspin, irisin, QUICKI, and eGDR (ACC = 86 [%]); as well as, (3) vaspin, irisin, LDL, HOMA-S, ACR, and eGFR (ACC = 86 [%]).

Effects of Spirulina supplementation on obesity: A systematic review and meta-analysis of randomized clinical trials

OBJECTIVE

Evidence has suggested that Spirulina supplementation may affect anthropometric indices. Therefore, a systematic review and meta-analysis was performed to summarize published randomized clinical trials which assess the effect of Spirulina supplementation on obesity.

SETTING

Pertinent studies were identified using Embase, Scopus, ISI Web of Science, PubMed and Cochrane library databases up to May 2019. Mean Differences (MD) were pooled using a random-effects model. Heterogeneity, sensitivity analysis and publication bias were reported using standard methods.

RESULTS

Results of 5 studies (7 treatment arms) showed a significant reduction in weight (MD: -1.56 Kg, 95% CI: -1.98 to -1.14) after Spirulina supplementation. Subgroup analysis based on health status revealed that weight change in obese subjects (MD: -2.06 Kg, 95% CI: -2.45 to -1.68) was greater than overweight participants (MD: -1.28 Kg, 95% CI: -1.62 to -0.93) following Spirulina supplementation. Also, pooled analysis showed that Spirulina supplementation led to a significant reduction in body fat percent (MD: -1.02, 95% CI: -1.49 to -0.54) and waist circumference (MD: -1.40, 95% CI: -1.40 to -1.39), but not in body mass index and waist to hip ratio.

CONCLUSION

Spirulina supplementation significantly reduces body weight, especially in obese individuals.

The Association between Vitamin D Deficiency and variants of Vitamin D Binding protein gene among Healthy Iranian Adults

Background: The high prevalence of vitamin D deficiency may be due to both genetic and environment factors. The aim of this study was to demonstrate that vitamin D deficiency may be due to variants of vitamin D binding protein (DBP) among otherwise healthy Iranian adults. Methods: This cross-sectional study was conducted on 265 healthy adults in Tehran. Anthropometric and biochemical parameters were assessed. Dietary vitamin D intake was assessed with a Food Frequency Questionnaire (FFQ), and participant DBP genotypes were determined by polymerase chain reactions - restriction fragment length polymorphism. Results: Significant associations were found between vitamin D status and low-density lipoprotein cholesterol (P < 0.001), total cholesterol (P < 0.001), and fasting blood sugar (P < 0.001), after adjustment for confounder factors. This study demonstrated that "rs7041" gene was associated with vitamin D deficiency (OR = 0.63, β ± SE = -0.46 ± 0.14, P < 0.0001). After considering the "GG" genotype of the "rs7041" polymorphism as a reference, the prevalence of vitamin D deficiency was found to be higher in the individuals with "TT" genotype from the "rs7041" polymorphism. Conclusion: It was found that the prevalence of vitamin D deficiency was higher in individuals with T allele carriers in the "rs7041" polymorphism.

The association between resting metabolic rate and metabolic syndrome May Be mediated by adipokines in overweight and obese women

AIMS

Adipokines play a major role in developing metabolic syndrome (MetS), and it has been found that there is a significant relationship between MetS and resting metabolic rate (RMR) in obese people. The present study aimed to investigate the mediatory effect of adipokines on the RMR-MetS relationship.

METHODS

This cross-sectional study included 263 obese and overweight women, mean BMI 33.28 (4.93) kg/m, and mean age 39.02 (11.60) who were assessed for RMR using indirect calorimetry. Moreover, using the body composition analyzer the Body composition was measured. Also, Enzyme-linked Immunosorbent Assay (ELISA) test provided a quantitative measurement of biochemical parameters.

RESULTS

The results indicated that women in low RMR group had higher fat mass (P < 0.0001), FFM (P = 0.002), weight (P = 0.006), BMI (P < 0.0001), age (P = 0.01), and hs-CRP (P = 0.001). The results did not confirm any significant mediating roles for RBP4 (P = 0.051, β = -0.28) and Vaspin (P = 0.06, β = 0.32) in the RMR-MetS relationship. Additionally, after a binary regression test, Omentin-1 showed a significant mediating role (P = 0.25, β = 0.04) as an interrelated agent to RMR and MetS.

CONCLUSION

As this study shows, Omentin-1 was found to play a significant mediating role as a mediatory agent in relationship between RMR and MetS.

Variants in the PPARGC1A Gene may Influence the Effect of Fat Intake on Resting Metabolic Rate in Obese Women

Recent studies have shown that dietary intake and genetic variants play a decisive role in the risk of obesity. Therefore, this study was designed to examine the interaction between dietary fat and PPARGC1A polymorphisms on the level of resting metabolic rate (RMR). We enrolled 288 Iranian overweight and obese women in this cross-sectional study. We sequenced the 648 b.p. DNA in Exon 8 of PPARGC1A gene. We analyzed the two single-nucleotide polymorphisms, namely rs11290186 and rs2970847, in this region. All participants were assessed for RMR, dietary intake, and body composition. This study demonstrated that total cholesterol and insulin levels were positively associated with T allele carriers of rs2970847. Moreover, the A-deletion allele carrier of the rs11290186 genotype had higher triacylglycerol and insulin concentrations. The current study revealed that, after adjustment for energy intake, the AA genotype of PPARGC1A (rs11290186) had a direct association with polyunsaturated fatty acids and linoleic acid intakes. Another important finding in our study was that there was an interaction seen between fat and saturated fatty acids intake with the PPARGC1A genotypes. Women with fat intakes of more than 30% of calorie intake per day and the A-deletion genotype had a lower RMR and RMR/fat free mass (FFM). It seems that the PPARGC1A polymorphisms lead to the downregulation of insulin signaling and subsequently insulin resistance. In addition, the interactions between the PPARGC1A polymorphisms (rs11290186) and the level of dietary fat intake probably can have an effect on RMR and RMR/FFM in obese women.

Rosuvastatin Improves Vaspin Serum Levels in Obese Patients with Acute Coronary Syndrome

Adipose tissue-derived serine protease inhibitor (vaspin), which has endocrine and local roles in atherosclerosis growth, is also synthesized by adipose tissue; it was found that vaspin was negatively correlated with blood pressure in obese patients, while vaspin levels were decreased in endothelial dysfunction. The aim of the present study was to determine rosuvastatin modulation effects on serum vaspin levels in acute coronary syndrome (ACS) with class I obesity. A total number of seventy patients with acute coronary syndrome previously and currently treated with rosuvastatin was compared to 40 patients with IHD not treated by rosuvastatin as a control. Vaspin serum levels were higher in rosuvastatin-treated patients with acute coronary syndrome compared to the patients with acute coronary syndrome not treated by rosuvastatin, p < 0.01. Additionally, in the rosuvastatin-treated group, patients with STEMI showed higher vaspin serum levels compared to NSTEMI p < 0.01. Conclusion: Rosuvastatin significantly increases vaspin serum levels in acute coronary syndrome.

Vitamin D Status and Resting Metabolic Rate May Modify through Expression of Vitamin D Receptor and Peroxisome Proliferator-Activated Receptor Gamma Coactivator-1 Alpha Gene in Overweight and Obese Adults

BACKGROUND

Resting metabolic rate (RMR) used to prognosticate and measure the amount of energy required. Vitamin D is known as a new predictor of RMR. The aim of this study is to investigate the relationship between vitamin D effects on RMR in connection with the vitamin D receptor (VDR) and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) gene expression.

METHODS

We enrolled 298 overweight and obese adults in this cross-sectional study. Body mass index (BMI), fat mass, fat-free mass, insulin level, visceral fat, and vitamin D status were assessed. RMR was measured by means of indirect calorimetry. The real-time polymerase chain reaction using specific primer pairs for VDR and PGC-1α was performed.

RESULTS

There were significant differences in terms of fat free mass, fat percentage, insulin levels, RMR/kg body weight, and RMR/BMI, VDR, and PGC-1α among participants were categorized based on the vitamin D status. But after using general linear model for adjusting, all significant results missed their effectiveness except RMR/kg body weight and VDR. Linear regression analysis used to show the mediatory role of VDR and PGC-1α on the RMR/kg body weight and vitamin D status relationship. Our results showed that VDR had a mediatory effect on the relationship between RMR/kg body weight and vitamin D status (β = 0.38, 95% CI -0.48 to 1.60; β = -1.24, 95% CI -5.36 to 1.70). However, PGC-1α did not affect the relationship between RMR/kg body weight and vitamin D status (β = 0.50, 95% CI = -0.02 to 3.42; β = 0.59, 95% CI 0.14-3.90).

CONCLUSION

Our study showed the mediatory effect of VDR gene expression in the association of 25(OH)2D plasma levels and resting metabolic rate among obese individuals.

Circulating omentin-1 might be associated with metabolic health status in different phenotypes of body size

OBJECTIVE

Adipokines are mediators of body composition and are involved in obesity complications. This study aimed to assess the association of circulating omentin-1, vaspin, and RBP-4 with body composition indices and metabolic health status (MHS) in different phenotypes of body size.

SUBJECTS AND METHODS

A total of 350 subjects were included in the current cross-sectional study. Body composition was measured using a body composition analyzer, and serum concentrations of omentin-1, vaspin, and RBP-4 were assessed by ELISA kits.

RESULTS

Circulating omentin-1 was significantly (OR = 1.81, 95% CI: 1.00-1.91, P = 0.01) and marginally (OR = 1.63, 95%CI: 1.00-1.75, P = 0.06) associated with MHS in the overweight and obese subjects, respectively. But no association was seen between omentin-1 and MHS in normal-weight subjects. Serum levels of vaspin and RBP-4 were not correlated with MHS. Furthermore, a significant positive correlation was observed between circulating omentin-1 and body mass index (BMI) as well as fat percentage (P = 0.02) in the MHS group. Serum vaspin concentrations were not related to body composition components in both groups. In addition, in the MHS group, circulating RBP-4 was positively correlated with fat percentage and fat mass (FM) (p < 0.0001) and was negatively correlated with fat-free mass (FFM) and total body water (TBW) (p < 0.0001). In contrast, in the metabolically unhealthy group, RBP-4 was negatively correlated with fat percentage, FM, and BMI (p < 0.0001) and was positively correlated with FFM and TBW (p < 0.0001).

CONCLUSIONS

This study showed that circulating levels of omentin-1 are useful predictors of metabolic health status in overweight and obese people.

Calorie restriction effects on circadian rhythms in gene expression are sex dependent

The rhythms in the expression of circadian clock genes are affected by calorie restriction (CR), a dietary paradigm known to increase lifespan. Many physiological effects of CR differ between males and females; here we investigated if the sex of animals affects the CR induced changes in the circadian rhythms. The liver expression of some circadian clock genes such as Bmal1 and three Periods (Per1, Per2 and Per3) and the effect of CR on the expression of these genes were sex independent, while the expression of Rev-Erb alpha, Ror gamma and both Cryptochome (Cry1 and Cry2) genes was different between males and females. The effect of CR on Rev-Erb alpha, Ror gamma and Cry1 gene expression was sex dependent. The expression and the effects of CR were sex-specific for several genes previously reported to be regulated by CR: Fmo3, Mup4, Serpina12 and Cyp4a12, while the expression of Cyp4a14a was sex independent. IGF signaling plays an important role in aging and CR effects. Igf-1 expression is regulated by CR and by the circadian clock, we found that rhythms in Igf-1 expression have sexual dimorphism. Our data provide molecular evidence that the sex of animals is an important modulator of circadian rhythms in gene expression and their response to CR.

Role of Omentin, Vaspin, Cardiotrophin-1, TWEAK and NOV/CCN3 in Obesity and Diabetes Development

Adipose tissue releases bioactive mediators called adipokines. This review focuses on the effects of omentin, vaspin, cardiotrophin-1, Tumor necrosis factor-like Weak Inducer of Apoptosis (TWEAK) and nephroblastoma overexpressed (NOV/CCN3) on obesity and diabetes. Omentin is produced by the stromal-vascular fraction of visceral adipose tissue. Obesity reduces omentin serum concentrations and adipose tissue secretion in adults and adolescents. This adipokine regulates insulin sensitivity, but its clinical relevance has to be confirmed. Vaspin is produced by visceral and subcutaneous adipose tissues. Vaspin levels are higher in obese subjects, as well as in subjects showing insulin resistance or type 2 diabetes. Cardiotrophin-1 is an adipokine with a similar structure as cytokines from interleukin-6 family. There is some controversy regarding the regulation of cardiotrophin-1 levels in obese -subjects, but gene expression levels of cardiotrophin-1 are down-regulated in white adipose tissue from diet-induced obese mice. It also shows anti-obesity and hypoglycemic properties. TWEAK is a potential regulator of the low-grade chronic inflammation characteristic of obesity. TWEAK levels seem not to be directly related to adiposity, and metabolic factors play a critical role in its regulation. Finally, a strong correlation has been found between plasma NOV/CCN3 concentration and fat mass. This adipokine improves insulin actions.

Serum Vaspin Concentration in Elderly Type 2 Diabetes Mellitus Patients with Differing Body Mass Index: A Cross-Sectional Study

Aims. This study was to evaluate the association of serum vaspin concentrations with body mass index (BMI) among elderly patients (>60 years old). Methods. A total of 227 elderly individuals included 76 healthy with normal glucose tolerance, which divided into normal weight control (BMI < 25, n = 38) and overweight or obese control (BMI ≥ 25, n = 38) subgroups, and 150 T2DM patients, which divided into normal weight diabetes (BMI < 25, n = 55), overweight diabetes (30 > BMI ≥ 25, n = 52), and obese diabetes (BMI ≥ 30, n = 43) subgroups. Relevant parameters were matched for age and gender ratio. Serum vaspin concentrations were measured by enzyme-linked immunosorbent assay. Results. Serum vaspin concentration was significantly higher in the T2DM than the healthy (451.9 ± 32.6 versus 284.2 ± 21.7, P < 0.01). In the diabetic patients, the vaspin concentration was significantly higher in the obese group than the normal weight group (498.2 ± 17.1 versus 382.1 ± 21.3, P < 0.05). In addition, the concentration of vaspin in normal weight T2DM was higher than in healthy control group with normal weight (382.1 ± 21.3 versus 192.5 ± 45.2, P < 0.05). Multiple regression analysis revealed that BMI was independent factors influencing the serum vaspin concentration in all participants. Conclusion. Vaspin may play an important compensatory role in obesity and insulin resistance in elderly people. The clinical trial registration number is ChiCTR-OPC-14005698.

Adipokines may mediate the relationship between resting metabolic rates and bone mineral densities in obese women

The researchers sought to test the possible link between resting metabolic rate and bone mineral density through four adipokines. Participants with lower resting metabolic rate (RMR) per kilogram demonstrated higher total bone mineral density (BMD), total T-score, and total Z-score. Omentin-1 had a mediatory effect on the relationship between RMR/kg of body weight and bone parameters.

INTRODUCTION

The previous results of studies regarding the links between obesity and bone health are controversial. For this reason, the researchers sought to test the possible link between RMR and BMD through the following four adipokines: vaspin, retinol binding protein 4, angiopoietin-like 6 (ANGPL6), and omentin-1.

METHODS

We enrolled 312 obese Iranian women (30 ≤ body mass index <40) in this cross-sectional study. In order to examine the association of serum adipokine levels with RMR and BMD, the participants were grouped based on RMR per body weight. Body composition, dietary intake, bone mineral density, and resting metabolic rate were assessed in all participants. Serum adipokine levels were quantified by the enzyme-linked immunosorbent assay (ELISA) method.

RESULTS

Low levels of RMR/kg were strongly associated with higher weight, body mass index, fat mass, and visceral fat levels. In fact, participants with an RMR/kg of body weight <20 kcal/24 h/kg were more obese (p < 0.05). Another noteworthy finding was that participants with lower RMR/kg demonstrated higher total BMD, total T-score, and total Z-score. Our results showed that omentin-1 had a mediatory effect on the relationship between RMR per kilogram of body weight and bone parameters (p < 0.05). Nevertheless, other adipokines such as vaspin, retinol-binding protein 4 (RBP4), and ANGPL6 did not affect the relationship between RMR and BMD (p > 0.05).

CONCLUSIONS

The inhibitory effect of omentin-1 on TNF-alpha seems to be able to reduce the amount of circulating leptin as adipokine, affecting energy expenditure and improving bone loss induced by estrogen deficiency and controlled effect of RMR on BMD.