Effect of glutamine supplementation on cardiometabolic risk factors and inflammatory markers: a systematic review and meta-analysis

Background: Evidence exists that glutamine plays multiple roles in glucose metabolism, insulin sensitivity, and anti-inflammatory effects. This systematic review and meta-analysis of controlled trials aimed to assess the effect of glutamine supplementation on cardio-metabolic risk factors and inflammatory markers. Methods: The processes of systematic reviews and meta-analyses were performed according to the PRISMA checklist. PubMed, Web of Sciences, Cochrane library, and Scopus databases were search for relevant studies without time or language restrictions up to December 30, 2020. All randomized clinical trials which assessed the effect of glutamine supplementation on �glycemic indices�, �level of triglyceride, �and �inflammatory markers� were included in the study. The effect of glutamine supplementation on cardio-metabolic risk factors and inflammatory markers was assessed using a standardized mean difference (SMD) and 95 confidence interval (CI). Heterogeneity between among studies was assessed using Cochran Q-statistic and I-square. Random/fixed-effects meta-analysis method was used to estimate the pooled SMD. The risk of bias for the included trials was evaluated using the Cochrane quality assessment tool. Results: In total, 12 studies that assessed the effect of glutamine supplementation on cardio-metabolic risk factors were included in the study. Meta-analysis showed that glutamine supplementation significantly decreased significantly serum levels of FPG SMD: � 0.73, 95% CI � 1.35, � 0.11, I2: 84.1% and CRP SMD: � 0.58, 95% CI � 0.1, � 0.17, I2: 0%. The effect of glutamine supplementation on other cardiometabolic risk factors was not statistically significant (P > 0.05). Conclusion: Our findings showed that glutamine supplementation might have a positive effect on FPG and CRP; both of which are crucial as cardio-metabolic risk factors. However, supplementation had no significant effect on other cardio-metabolic risk factors. © 2021, The Author(s)

Interleukin 4 gene polymorphism (−589C/T) and the risk of asthma: a meta-analysis and met-regression based on 55 studies

Background: Numerous investigations have previously evaluated the association of interleukin (IL) 4 gene polymorphisms and the risk of asthma, conferring inconsistent results. To resolve the incongruent outcomes yielded from different single studies, we conducted the most up-to-date meta-analysis of IL4 gene −589C/T (rs2243250) polymorphism and susceptibility to asthma. Methods: A systematic literature search was performed in ISI web of science, Scopus, Medline/PubMed databases prior to September 2020, and the pooled odds ratio (OR) and their corresponding 95% CI were calculated to determine the association strength. Results: Literature search led to retrieving of 49 publications (55 case-control studies) containing 9572 cases and 9881 controls. It was revealed that IL4 gene −589C/T polymorphism increased the risk of asthma across all genetic models, including dominant model (OR = 1.22), recessive model (OR = 1.17), allelic model (OR = 1.21), and TT vs. CC model (OR = 1.34), but not the CT vs. TT model. The subgroup analysis by age indicated that IL4 gene -589C/T polymorphism was significantly associated with asthma risk in both pediatrics and adults. Additionally, the subgroup analysis by ethnicity revealed significant association in Asian, American, and Europeans. Finally, subgroup analysis by East Asian and non-East Asian populations indicated significant associations. Conclusions: The current meta-analysis revealed that IL4 gene -589C/T polymorphism was a susceptibility risk in both pediatrics and adults in the whole and different ethnic groups

Economic inequality in prevalence of underweight and short stature in children and adolescents: The weight disorders survey of the caspian-IV study

Objective: The aim of this study was to determine the determinants of socio-economic inequality in the prevalence of short stature and underweight in Iranian children and adolescents. Subjects and methods: This cross-sectional nationwide study was conducted on 36,486 participants, aged 6-18 years. This school-based surveillance (CASPIAN-IV) program and its complementary part on weight disorders evaluation was conducted in urban and rural areas of 30 provinces in Iran. In addition to physical examination, a validated questionnaire was completed from students and their parents. Socio-economic status (SES) was determined using principal component analysis, and was classified in quintile scale. Inequality in the prevalence of underweight and short stature was assessed using concentration (C) index and slop index of inequality (SII) by the Oaxaca-Blinder decomposition method. Results: The prevalence (95 CI) of underweight and short stature at national level was 10.89 (10.55, 11.23) and 4.15 (3.94, 4.38), respectively; it had a downtrend from the lowest to highest SES quintile. Furthermore, the value of C for underweight and short stature was negative, i.e. inequality was in favor of high SES groups. Moreover, the prevalence gap of underweight and short stature in the first and fifth quintiles of SES was 6.58 and 5.80, respectively. The highest proportion of this gap was explained by living area. In the multiple logistic model, odds of underweight and short stature were significantly lower in individuals with higher SES. Compared to boys, odds of underweight were decreased in girls, whereas odds of short stature were increased in them. Odds of underweight and short stature were increased in participants from rural areas than in urban areas. With increasing age, the odds of underweight and short stature decreased significantly. Conclusions: The results of this study showed that inequality in the prevalence of short stature and underweight was in favor of high SES groups. Moreover, living area was one of the most important determinants that explained this inequality. Therefore, this issue needs to be considered in health promotion policies. © 2020, Sociedade Brasileira de Endocrinologia e Metabologia. All rights reserved

Anti-fibrotic effects of curcumin and some of its analogues in the heart.

Cardiac fibrosis stems from the changes in the expression of fibrotic genes in cardiac fibroblasts (CFs) in response to the tissue damage induced by various cardiovascular diseases (CVDs) leading to their transformation into active myofibroblasts, which produce high amounts of extracellular matrix (ECM) proteins leading, in turn, to excessive deposition of ECM in cardiac tissue. The excessive accumulation of ECM elements causes heart stiffness, tissue scarring, electrical conduction disruption and finally cardiac dysfunction and heart failure. Curcumin (Cur; also known as diferuloylmethane) is a polyphenol compound extracted from rhizomes of Curcuma longa with an influence on an extensive spectrum of biological phenomena including cell proliferation, differentiation, inflammation, pathogenesis, chemoprevention, apoptosis, angiogenesis and cardiac pathological changes. Cumulative evidence has suggested a beneficial role for Cur in improving disrupted cardiac function developed by cardiac fibrosis by establishing a balance between degradation and synthesis of ECM components. There are various molecular mechanisms contributing to the development of cardiac fibrosis. We presented a review of Cur effects on cardiac fibrosis and the discovered underlying mechanisms by them Cur interact to establish its cardio-protective effects

Association of wrist circumference with cardio-metabolic risk factors: a systematic review and meta-analysis

Background and aims: The association of Wrist Circumference (WrC) with cardio-metabolic risk factors is still contradictory. We aimed to systematically review the association of WrC with cardio-metabolic diseases among the general populations. Methods: We systematically searched electronic databases such as PubMed/Medline, Web of Sciences, and Scopus without language restriction until March 2017. Observational studies that examined the association of WrC with any cardio-metabolic risk factors were included. Pooled association of WrC with metabolic syndrome (MetS) was estimated using a random-effect model, and heterogeneity among studies was assessed by I2 index and Q test. Results: A total of 14 papers including cohort study (n = 9), cross-sectional study (n = 4), and case�control study (n = 1) met the criteria and included. The eligible papers have been examined the association of WrC with any cardiovascular disorders (n = 8), metabolic syndrome (n = 4), insulin resistance (IR) (n = 5), diabetes mellitus (n = 2), impaired glucose tolerance (n = 1), cardio-metabolic risk factors (n = 2) and obesity/overweight (n = 1). In the whole population (both adults and pediatric population), high WrC increased the risk of MetS by 33 (Pooled OR = 1.33; 95 CI 1.20, 1.48; I2 = 60.2, p = 0.04), while the pooled OR in adult populations was 1.27 (95 CI 1.15�1.41; I2: 32.8, p = 0.21). Qualitative synthesis showed that associations of WrC with other cardio-metabolic risk factors are conflicting. Conclusion: High WrC increased the risk of MetS and other cardio-metabolic risk factors. However, due to limited studies, particularly in children, results should be declared with great caution. Further cohort studies are needed to clarify whether WrC is a suitable anthropometric index to predict cardio-metabolic disorders in adult and children populations in different societies. Level of evidence: Level 1, systematic review and meta-analysis © 2018 Springer International Publishing AG, part of Springer Natur

Association of wrist circumference with cardio-metabolic risk factors: a systematic review and meta-analysis

Background and aims: The association of Wrist Circumference (WrC) with cardio-metabolic risk factors is still contradictory. We aimed to systematically review the association of WrC with cardio-metabolic diseases among the general populations. Methods: We systematically searched electronic databases such as PubMed/Medline, Web of Sciences, and Scopus without language restriction until March 2017. Observational studies that examined the association of WrC with any cardio-metabolic risk factors were included. Pooled association of WrC with metabolic syndrome (MetS) was estimated using a random-effect model, and heterogeneity among studies was assessed by I2 index and Q test. Results: A total of 14 papers including cohort study (n = 9), cross-sectional study (n = 4), and case�control study (n = 1) met the criteria and included. The eligible papers have been examined the association of WrC with any cardiovascular disorders (n = 8), metabolic syndrome (n = 4), insulin resistance (IR) (n = 5), diabetes mellitus (n = 2), impaired glucose tolerance (n = 1), cardio-metabolic risk factors (n = 2) and obesity/overweight (n = 1). In the whole population (both adults and pediatric population), high WrC increased the risk of MetS by 33 (Pooled OR = 1.33; 95 CI 1.20, 1.48; I2 = 60.2, p = 0.04), while the pooled OR in adult populations was 1.27 (95 CI 1.15�1.41; I2: 32.8, p = 0.21). Qualitative synthesis showed that associations of WrC with other cardio-metabolic risk factors are conflicting. Conclusion: High WrC increased the risk of MetS and other cardio-metabolic risk factors. However, due to limited studies, particularly in children, results should be declared with great caution. Further cohort studies are needed to clarify whether WrC is a suitable anthropometric index to predict cardio-metabolic disorders in adult and children populations in different societies. Level of evidence: Level 1, systematic review and meta-analysis © 2018, Springer International Publishing AG, part of Springer Nature

Percentile values for serum levels of vitamins A and D in Iranian children and adolescents: The CASPIAN-V study

Objectives: The reference values to determine vitamin A and D deficiency may vary based on ethnicity, age, and region of residence. The aim of this study was to determine the reference interval of circulating vitamin A and D levels among Iranian children and adolescents based on sex, age, and region of residence. Methods: This nationwide cross-sectional study was performed with 2596 students 7 to 18 y of age from the CASPIAN-V (Childhood and Adolescence Surveillance and Prevention of Adult Non- communicable disease) study. A parametric method was used to define the age-specific reference values by obtaining smooth centile curves and explicit formulae for the centile estimates and SD scores for both sexes and regions of residence. Results: Significant differences were found between the residents of rural and urban regions in terms of serum 25-hydroxyvitamin D 25(OH)D and retinol concentration (P < 0.05). Boys (27 ± 8 versus 26.04 ± 10, P = 0.009). Children ages 7 to 12 y had higher serum 25(OH)D concentration than 13- to 18-y-old adolescents (26.96 ± 8 versus 26.04 ± 10, P = 0.007). The estimated reference interval for circulating 25(OH)D levels corresponding to the range between the 5th and 95th percentiles were 11.45 to 48.40 ng/mL in boys and 9.51 to 47.69 ng/mL in girls. Estimated reference intervals for serum retinol concentration among boys and girls corresponding to the 5th and 95th percentiles were 0.58 to 3.38 and 0.58 to 4.52, respectively. There were significant variations in both retinol and 25(OH)D concentrations across different age groups. Conclusion: This study established the reference intervals for circulating 25(OH)D and retinol levels in Iranian adolescents and children in different age groups based on sex and region. © 2021 Elsevier Inc

The effects of dietary selenium supplementation on inflammatory markers among patients with metabolic diseases: a systematic review and meta-analysis of randomized controlled trials

Purpose: Selenium (Se) is a trace element having significant effects on human metabolism. Recent studies suggest that Se supplementation have a pivotal effect on the inflammatory markers. Therefore, the aim of this study was to assess the effect of Se supplementation on plasma inflammatory markers including C-reactive protein (CRP) and high-sensitivity C-reactive protein (hs-CRP) and nitric oxide (NO) as a stress oxidative index, among patients with metabolic diseases. Methods: To assess the effects of Se on the inflammatory markers, following the PRISMA-P guidelines, we systematically searched ISI/WOS, PubMed/MEDLINE, and Scopus for studies that assessed the effect of Se supplementation on the inflammatory markers. Data extraction was performed by two independent investigators. Using the random effects or fixed-effects model depending on the results of heterogeneity tests was used to estimate the pooled standardized mean difference (SMD). Heterogeneity between studies was assessed using Cochran's Q test and I2 index. Results: The initial search revealed 3,320 papers. After screening process and considering inclusion criteria, 7 publications were eligible for inclusion in the meta-analysis. The meta-analysis results showed that Se supplementation did not significantly affect CRP and hs-CRP concentrations (mean difference (MD) = -0.15; 95 CI: -0.55- 0.23; P = 0.43). Subgroup analysis of CRP type showed that Se supplementation significantly decreased hs-CRP level (pooled SMD = -0.44; 95 CI: -0.67�0.21). Moreover, no significant change was observed in NO level by continuing to take Se supplementation, (pooled SMD: 0.003, 95CI: -0.26, 0.26). Conclusions: This study revealed that Se supplementation would have desirable effects on cardio-metabolic indicators through affecting the levels of inflammatory markers. Given the importance of concerns, more attention should be given to more prospective studies with longer follow-up. © 2021, Springer Nature Switzerland AG

Validity of continuous metabolic syndrome score for predicting metabolic syndrome; a systematic review and meta-analysis

Background: Nowadays, use of continuous metabolic syndrome (cMetS) score has been suggested to improve recognition of metabolic syndrome (MetS). The aim of this study was to evaluate the validity of cMetS scores for predicting MetS. Methods: We searched the electronic databases included MEDLINE/PubMed, Embase, ISI Web of Science, and Scopus from 1 January 1980 to 30 September 2020. Observational studies on participants with different cMetS scores were included in this meta-analysis. The sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR) and diagnostic odds ratio (DOR) with 95 CI were calculated. Results: Ten studies involving a total of 25,073 participants were included. All studies had cross-sectional design. The pooled sensitivity and specificity of cMetS scores for predicting MetS were 0.90 (95 CI: 0.83 to 0.95) and 0.86 (95 CI: 0.83 to 0.89), respectively. Moreover, cMetS scores had the pooled LR+ of 6.5 (95 CI: 5.0 to 8.6), and a pooled (LR-) of 0.11 (95 CI: 0.063 to 0.21). The pooled DOR of cMetS scores to predict MetS were 57 (95 CI: 26 to 127). Conclusions: The high sensitivity and specificity of cMetS scores indicates that it has a high accuracy to predict the risk of MetS. Furthermore, the cMetS scores has a good ability to rule out healthy people. Study registration: This study was registered as PROSPERO CRD42020157273. © 2021, Springer Nature Switzerland AG