Irisin In Adults Research Articles

Association of Gastric Myoelectrical Activity With Ghrelin, Gastrin, and Irisin in Adults With Metabolically Healthy and Unhealthy Obesity.

Background and Objective: Functional disturbances of gastric myoelectrical activity (GMA) might exist in obesity. However, studies on its association with the gastric hormones in obesity phenotypes are lacking. The objective was to study the association of GMA with the serum levels of key gastric hormones in different obesity phenotypes. Methods: A total of 139 adults (31.00 ± 11.12 years) were classified into different metabolic phenotypes of obesity: 1) normal weight-lean (NWL group): BMI <25 kg/m2 and the fat-mass index (FMI) ≤9.7 kg/m2 in females and ≤6.3 kg/m2 in males; 2) metabolically obese normal weight (MONW group): BMI <25 kg/m2 and FMI >9.7 kg/m2 in females and >6.3 kg/m2 in males; 3) metabolically healthy obese (MHO group): BMI ≥25 and FMI ≤9.7 kg/m2 in females and ≤6.3 kg/m2 in males; and 4) metabolically unhealthy obese (MUO group): BMI ≥25 and FMI >9.7 kg/m2 in females and >6.3 kg/m2 in males. The GMA was measured at the baseline and post-prandial state using a multichannel electrogastrography with a water load satiety test. The average power distribution by the frequency region and the average dominant frequency were used for analysis. Anthropometric measurements and bioelectric impedance analysis were performed to calculate the FMI and fat-free mass index (FFMI). Serum levels of ghrelin, gastrin, and irisin were measured by ELISA kits according to the manufacturer’s protocol. Results: Compared to the NWL group, gastrin and ghrelin levels were significantly low in the MUO participants, while irisin was significantly high. The EGG showed significantly lower baseline and 20-min normogastria frequencies in the MHO and MUO groups. In the MHO group, baseline duodenal frequency was positively correlated with the gastrin level, while normogastria times were positively associated with the irisin level and negatively associated with the ghrelin level. In the MUO group, percentages of bradygastria frequencies at 10, 20, and 30 min were positively correlated with the BMI and FFMI. This bradygastria was correlated positively with the irisin level and negatively with the ghrelin level. Conclusion: The EGG patterns might be associated with obesity-related gastric hormones in different obesity phenotypes. EGG may be a promising clinical tool in obesity assessment. The association of the EGG patterns with hormonal levels needs further investigation for potential practical uses.

The effect of exercise interventions on Irisin level: a systematic review and meta-analysis of randomized controlled trials.

Irisin is a hormone that is offered to be a hopeful remedial target in obesity and type 2 diabetes. It has received striking attention recently, whereas, the interactions between exercise training and irisin are still unclear. Therefore, this systematic review and meta-analysis investigated the impacts of exercise interventions on circulating irisin in adults. A systematic search was conducted in PubMed, CINAHL, MEDLINE, Cochrane, Google Scholar, and Scopus up to July 15, 2021. Twenty-four studies, which assessed a total of 921 participants were included and analyzed using a random-effects model to estimate weighted mean differences (MD) with 95 % confidence intervals (CI). Overall, data revealed that exercise training significantly increased circulating irisin (MD: 0.01, 95 % CI: 0.00, 0.01, p = 0.005), and declined insulin (MD: -2.09, 95 % CI: -2.81, -1.37, p < 0.00001), glucose (MD: -12.89, 95 % CI: -16.52, -9.26, p < 0.00001), and insulin resistance (MD: -0.89, 95 % CI: -1.15, -0.62, p < 0.00001). Subgroup analysis revealed that irisin raised significantly when resistance training (p = 0.04) and combined training (p = 0.002) were applied, and for the type 2 diabetes and prediabetes (p = 0.002 for both) groups. Moreover, subgroup analysis by the type of intervention demonstrated that insulin reduced when aerobic training (p < 0.00001) and combined training (p = 0.0003) were employed, but glucose and HOMA-IR reduced after all three types of exercise training. These findings demonstrate that exercise interventions may produce ameliorations in circulating irisin. Further long-term studies are required to confirm these findings.

Blood serum myokine irisin and adipocytokine levels in newborns small for gestational age at birth

In recent years, a number of the studies of myokine irisin in adults and isolated in newborns have been carried out. The role of adipocytokines in the growth and development of the fetus and children has been shown.The aim of the study was to assess the levels of myokine irisin and adipocytokines in newborns small for gestational age at birth and to analyze the relationship between the parameters of the hormonal status of children and their mothers.49 newborns and their mothers were examined. Two groups were identified: group 1 (Gr1) – newborns small for gestational age (n = 24), group 2 (Gr2) – newborns appropriate for gestational age (n = 25). The levels of irisin and adipocytokines in the blood serum were determined by the enzyme immunoassay.Newborns small for gestational age had significantly lower levels of leptin and IGF-1 in the umbilical cord blood compared to children with physical development corresponding to the gestational age. There were no significant differences in the irisin content of cord blood serum in newborn Gr1 compared with Gr2. The presence of significant positive correlations between the level of irisin in the umbilical cord blood of newborns small for gestational age and the body weight at birth was established. In Gr1, a positive relationship was found between the irisin levels of mothers and newborns (r = 0.518, p = 0.028). The differences in the irisin content between the groups were established, taking into account the delivery mode (p = 0.0104).The revealed statistically significant differences in the concentrations of the analyzed metabolic markers in mother–child pairs, their relationship with clinical and anthropometric parameters substantiate the possibility of using irisin and adipocytokines as predictors in predicting the formation of metabolic disorders of infants small for gestational age.

Effect of Chronic Resistance Training on Circulating Irisin: Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Irisin seems to play an important role in several chronic diseases, however, the interactions between chronic training and irisin are still unclear. The purpose of this systematic review and meta-analysis was to examine the effect of chronic resistance training on circulating irisin in adults. Literature search was conducted in PubMed, Web of Science and EBSCOhost (Academic Search Complete) until December 2020. Randomized controlled trials researching irisin levels after a resistance training program for at least 8 weeks among an adult population were eligible. Other inclusion criteria comprised recruiting a control group and reporting circulating irisin through ELISA kits. Cohen’s d effect size and subgroup analyses (95% confidence level) were calculated using a random effects analysis model. Data of the seven included studies comprising 282 individuals showed an increasing and non-significant tendency after a resistance training program (d = 0.58, 95% CI: −0.25 to 1.40, p = 0.17). Subgroup analyses showed significant increases for the older adults group (p < 0.001) and when training is demanding and progressive in terms of intensity (p = 0.03). Data suggest that resistance training programs seem to increase circulating irisin, especially in older adults and in demanding and progressive training programs. However, more studies should be conducted using robust measurement methods, such as mass spectrometry, to better understand the interaction between chronic resistance exercise and irisin.

Blunted circulating irisin in adults with type 1 diabetes during aerobic exercise in a hot environment: a pilot study

Irisin is a novel myokine associated with increased metabolism, which may be upregulated in type 1 diabetes (T1D) during exercise-heat stress. We therefore assessed serum irisin production in young adults with and without T1D during incremental exercise in dry-heat (35 °C). The change in irisin during exercise was lower in individuals with compared with without T1D (-1.79 (SEM 25.68) vs. 59.74 (SEM 79.63) pg/mL; p = 0.024), indicating that irisin expression during exercise-heat stress is blunted in T1D. Novelty We show that, when assessed in young adults with and without T1D during exercise-heat stress, serum irisin production is blunted in T1D.

Chronic Exercise Training and Circulating Irisin in Adults: A Meta-Analysis.

Irisin is a newly discovered hormone that is proposed to be a promising therapeutic target in obesity and type 2 diabetes. It has received remarkable attention recently, while inconsistent results have been shown regarding its association with chronic exercise training in adults. The aim of this study was to evaluate the effects of chronic exercise training on circulating (plasma/serum) irisin in adults by meta-analyzing randomized controlled trials (RCTs) and non-randomized studies (NRSs) separately. We conducted a search of the PubMed, Web of Science and Cochrane Library databases from January 2012 to September 2014 for studies published in English. Studies were included if they had an assessment of chronic (≥8 weeks) exercise training effects on circulating irisin in the general or clinical population (mean age ≥18 years) with reported outcomes of circulating irisin, and involved more than five participants. Pooled effect sizes (Cohen's d) with 95 % confidence intervals (CIs) for changes in circulating irisin were calculated by a random-effects model. Subgroup analyses were performed to evaluate the association between exercise modes and changes in circulating irisin. Of the 181 articles screened, 12 studies in eight articles were included, of which three were RCTs and nine were NRSs. In the three RCTs (a total of 173 healthy, untrained participants), chronic exercise training was associated with a moderate and significant overall effect in decreasing circulating irisin compared with the control (d = -0.46; 95 % CI -0.76 to -0.15). Chronic resistance exercise training showed a moderate and significant effect in decreasing circulating irisin compared with the control (d = -0.41; 95 % CI -0.75 to -0.06), while endurance exercise training only had a trend (d = -0.64; 95 % CI -1.32 to 0.04). In the nine NRSs (a total of 113 intervention participants), chronic exercise training was associated with a trivial and non-significant overall effect in decreasing circulating irisin compared with baseline (d = -0.04; 95 % CI -0.30 to 0.23). Chronic exercise training leads to significantly decreased circulating irisin levels in the RCTs, while evidence remains inconclusive in the NRSs. Well-designed RCTs that measure dietary intake and report changes of body fat percentage or insulin sensitivity/resistance index following chronic exercise training are required to confirm these findings.

Maternal inheritance of circulating irisin in humans (954.1)

Background The recently discovered myokine irisin has been implicated in several observational studies, suggesting a potential therapeutic target for obesity‐related diseases. However, no information is available as to the heritability of this hormone. This study aims to fill this gap.Methods A total of 120 families (N=254;121 adults and 133 children) were included in this study taken from the Biomarkers Research Program cohort. Information included anthropometrics, glycemic, lipid and adipocytokine profiles. Irisin was measured using ELISA.Results The most significant heritable traits in sons included irisin (p=1.6*10‐5), systolic blood pressure (p=3.6*10‐4), LDL‐ (p=1.2*10‐6) and total cholesterol (p=3.5*10‐7). Heritable traits between mother and daughter again included irisin (p&lt;0.002), as well as waist (p&lt;0.01), hips (p&lt;0.005) and blood pressure (p&lt;0.002); HDL‐cholesterol was the single most significant predictor for irisin in adults, explaining 17% of variance, whilst in children angiotensin II was the most significant predictor of irisin explaining 19% of variance (p=0.003).Conclusion Circulating irisin appears to be maternally inherited and is predicted by HDL‐cholesterol in adults and angiotensin II in children, both factors influenced by energy expenditure and regulation. Taken together, these findings suggest a significant role of irisin in energy‐generating processes.