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PloS One 2023The importance of leptin in controlling body mass has recently gained more attention. Its levels are directly associated with the amount of fat mass, but not necessarily... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The importance of leptin in controlling body mass has recently gained more attention. Its levels are directly associated with the amount of fat mass, but not necessarily dependent on it. Exercise has great potential in reducing leptin levels, however the response of exercise to this cytokine is still not well understood.
OBJECTIVE
The objective of the review was to analyze the effects of physical exercise on plasma leptin concentration, either acutely (post-exercise/training session) and/or after a training period (short- or long-term), as well as to investigate the existence of possible moderating variables.
METHODS
The studies included in this systematic review were published between 2005 and May 2023. Only peer-reviewed studies, available in English, performed with humans that evaluated the effects of any form of exercise on leptin levels were included. The search was conducted on May 03, 2023, in Embase (Elsevier), MEDLINE via PubMed®, and Web of Science (Core collection). The risk of bias in the included trials was assessed by the Physiotherapy Evidence Database tool, considering 11 questions regarding the methodology of each study with 10 questions being scored. The data (n, mean, and standard deviation) were extracted from included studies to perform random effects meta-analyses using standardized mean difference between the pre- and post-intervention effects.
RESULTS
Twenty-five studies (acute effect: 262 subjects; short- and long-term effect: 377 subjects) were included in this systematic review and meta-analysis. Short- and long-term physical exercise and caloric restriction plus exercise reduce plasma leptin levels, presenting statistically significant differences (p<0.001); as well as acute effect (p = 0.035), however the latter result was influenced by the pre-exercise meal as shown in the subgroup analysis. In this meta-analysis the effect of moderating factors on leptin reduction, not addressed by past reviews, is verified, such as the relationship with caloric restriction, exercise intensity and pre-exercise meal on acute responses.
CONCLUSION
Both acute and chronic exercise reduce leptin levels, yet the acute effect is dependent on the pre-exercise meal. In addition to having a long-term reduction in leptin levels, the minimum amount of weekly exercise to have a significant reduction in plasma leptin is 180 minutes of moderate-intensity exercise and 120 minutes of high-intensity exercise.
Topics: Humans; Caloric Restriction; Leptin; Exercise; Fasting
PubMed: 38015889
DOI: 10.1371/journal.pone.0288730 -
Inflammatory Bowel Diseases Apr 2024Inflammatory bowel disease (IBD), pathologically known as chronic inflammation of the gastrointestinal tract, is among the diseases with a high burden worldwide. Ghrelin... (Meta-Analysis)
Meta-Analysis
Unveiling the Ghrelin and Obestatin Roles in Inflammatory Bowel Diseases: A Systematic Review and Meta-Analysis Assessing Their Pathogenic Implications and Biomarker Utility.
BACKGROUND
Inflammatory bowel disease (IBD), pathologically known as chronic inflammation of the gastrointestinal tract, is among the diseases with a high burden worldwide. Ghrelin and obestatin, as adipocytokines mainly in adipose tissues, are involved in immune responses and inflammatory pathways. Studies have assessed the circulatory ghrelin levels in patients with IBD. Herein, we aim to pool these studies through systematic review and meta-analysis.
METHODS
Four international databases, PubMed, Embase, Scopus, and the Web of Science were systematically searched for studies assessing ghrelin or obestatin levels in patients with IBD (either Crohn's disease [CD] or ulcerative colitis [UC]) in active phase or in remission. Random-effects meta-analysis was conducted in order to calculate the pooled estimate using the standardized mean difference (SMD) and 95% confidence interval (CI).
RESULTS
Nineteen studies were included in our systematic review, comprising 1064 patients with IBD (476 UC and 588 CD). A meta-analysis of 11 studies for comparison of active and quiescent disease showed that patients with active IBD had significantly higher levels of ghrelin (SMD, 0.70; 95% CI, 0.06 to 1.34; P = .03). However, in separate analyses for UC or CD, no such difference was observed (SMD, 1.30; 95% CI, -0.28 to 2.88, P = .11; and SMD, 0.80; 95% CI, -0.41 to 2.01; P = .20, respectively). No significant difference was also observed in ghrelin levels between patients with active IBD and healthy control subjects. Obestatin levels also were not different between patients with active disease and those in remission (SMD, 0.31; 95% CI, -0.05 to 0.68; P = .09). On the other hand, the obestatin/ghrelin ratio was significantly lower in patients with active IBD (SMD, -1.90; 95% CI, -2.45 to -1.35; P < .01).
CONCLUSIONS
Our results demonstrate that IBD patients with active disease have higher levels of ghrelin, which needs to be confirmed in future studies. Also, the obestatin/ghrelin ratio might be a promising biomarker for the assessment of disease activity.
Topics: Humans; Ghrelin; Inflammatory Bowel Diseases; Crohn Disease; Colitis, Ulcerative; Biomarkers
PubMed: 37669127
DOI: 10.1093/ibd/izad202 -
Current Molecular Medicine Sep 2023Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver condition worldwide. NAFLD is often associated with features of Metabolic Syndrome such as... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver condition worldwide. NAFLD is often associated with features of Metabolic Syndrome such as obesity and insulin resistance.
METHOD
The current comprehensive meta-analysis was performed to evaluate the association between circulating Omentin levels and NAFLD. A systematic search in Scopus, Web of Science, PubMed, and Google Scholar databases was conducted to identify relevant studies up until 5th May 2022. The standard mean difference (SMD) values and 95% confidence intervals (CIs) were computed for the association of Omentin levels with NAFLD risk in a random effect model.
RESULT
The meta-analysis involved 6 case-control studies with a total of 371 cases and 269 controls. Pooled SMD showed no significant difference in serum Omentin between NAFLD and healthy groups (SMD= -0.047 and 95% CI -0.957_0.862 P=0.91). Subgroup analysis based on sample size showed that the average Omentin levels were significantly higher in NAFLD patients in studies with sample size ≥70 (SMD=0.356 CI 0.056_0.655 P=0.02).
CONCLUSION
Additional well-designed studies with more sample sizes are essential to clarify the potential role of Omentin as a risk marker of NAFLD.
PubMed: 37711002
DOI: 10.2174/1566524023666230913105910 -
Frontiers in Nutrition 2024Intermittent fasting (IF) and exercise training (Exe) have been evaluated in several studies for improving cardiometabolic biomarkers related to weight loss. However,...
Effects of intermittent fasting combined with exercise on serum leptin and adiponectin in adults with or without obesity: a systematic review and meta-analysis of randomized clinical trials.
CONTEXT
Intermittent fasting (IF) and exercise training (Exe) have been evaluated in several studies for improving cardiometabolic biomarkers related to weight loss. However, further investigation is required to understand the potential effects on leptin and adiponectin concentrations. IF protocols have been shown to be efficient in improving adipokines, but further research is required to determine whether or not IF regimens combined with Exe are superior to Exe alone.
OBJECTIVE
The aim of this study was to determine whether or not interventions combining IF plus Exe are more effective than Exe only for improving serum leptin and adiponectin in adults with and without obesity.
DATA EXTRACTION
A systematic review and meta-analysis was performed by searching PubMed, Scopus, and Web of Science databases up to August 2023 for randomized clinical trials that determined the effects of IF plus Exe vs. Exe alone (control) on body weight, serum leptin, and serum adiponectin. Analyses were conducted for IF plus Exe vs. Exe alone to calculate weighted mean differences (WMD) and standardized mean differences (SMD).
ANALYSIS
The current meta-analysis included 6 studies with a total sample of 153 participants, with intervention durations ranging from three days to 52 weeks. IF plus Exe elicited significantly larger decreases in leptin levels [SMD = -0.47, = 0.03], which were accompanied by weight loss [WMD = -1.25 kg, = 0.05], as compared with exercise-only interventions, but adiponectin did not differ between the two [SMD = 0.02, = 0.9].
CONCLUSION
IF combined with Exe reduced leptin significantly, but did not change adiponectin levels, when compared to exercise only. Perhaps these reductions in leptin levels may have been associated with weight loss; however, due to the small number of included studies and the high heterogeneity in the weight loss outcomes, this result is uncertain.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/, identifier CRD42023460735.
PubMed: 38933888
DOI: 10.3389/fnut.2024.1362731 -
Obesity (Silver Spring, Md.) Jun 2024The objective of this meta-analysis was to quantify the overall effects of gene mutations in the leptin-melanocortin pathway on short- and long-term weight loss after... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
The objective of this meta-analysis was to quantify the overall effects of gene mutations in the leptin-melanocortin pathway on short- and long-term weight loss after bariatric surgery.
METHODS
MEDLINE, PubMed, and Embase were searched, and data were analyzed using ReviewManager (RevMan) version 5.4. The datasets were divided into two subgroups based on postoperative time, and the outcome measure was the percentage of total weight loss. Meta-regression analysis was performed, and the outcome was presented as the weighed mean difference of percentage of total weight loss.
RESULTS
The results showed that patients with mutations in the leptin-melanocortin pathway experienced 3.03% lower total weight loss after bariatric surgery (mean difference, -3.03; 95% CI: -3.63 to -2.44), mainly reflected in lower long-term postoperative weight loss (mean difference, -3.43; 95% CI: -4.09 to -2.77), whereas mutation carriers exhibited a magnitude of short-term postoperative weight loss that was similar to patients without such mutations (total difference value, -1.13; 95% CI: -2.57 to 0.31).
CONCLUSIONS
Mutations in leptin-melanocortin pathway genes reduce long-term weight loss after bariatric surgery, whereas this effect may not be reflected during the period of rapid weight loss within 12 months. These genetic variants increase the difficulties in maintaining patients' long-term weight loss.
Topics: Humans; Leptin; Bariatric Surgery; Weight Loss; Mutation; Melanocortins; Obesity, Morbid; Signal Transduction; Obesity
PubMed: 38577709
DOI: 10.1002/oby.24007 -
BMC Psychiatry Jul 2024Increasing evidence suggests that leptin is involved in the pathology of autism spectrum disorder (ASD). In this study, our objective was to investigate the levels of... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Increasing evidence suggests that leptin is involved in the pathology of autism spectrum disorder (ASD). In this study, our objective was to investigate the levels of leptin in the blood of children with ASD and to examine the overall profile of adipokine markers in ASD through meta-analysis.
METHODS
Leptin concentrations were measured using an enzyme-linked immunosorbent assay (ELISA) kit, while adipokine profiling, including leptin, was performed via meta-analysis. Original reports that included measurements of peripheral adipokines in ASD patients and healthy controls (HCs) were collected from databases such as Web of Science, PubMed, and Cochrane Library. These studies were collected from September 2022 to September 2023 and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Standardized mean differences were calculated using a random effects model for the meta-analysis. Additionally, we performed meta-regression and explored heterogeneity among studies.
RESULTS
Our findings revealed a significant increase in leptin levels in children with ASD compared to HCs (p = 0.0319). This result was consistent with the findings obtained from the meta-analysis (p < 0.001). Furthermore, progranulin concentrations were significantly reduced in children with ASD. However, for the other five adipokines analyzed, there were no significant differences observed between the children with ASD and HCs children. Heterogeneity was found among the studies, and the meta-regression analysis indicated that publication year and latitude might influence the results of the meta-analysis.
CONCLUSIONS
These findings provide compelling evidence that leptin levels are increased in children with ASD compared to healthy controls, suggesting a potential mechanism involving adipokines, particularly leptin, in the pathogenesis of ASD. These results contribute to a better understanding of the pathology of ASD and provide new insights for future investigations.
Topics: Humans; Autism Spectrum Disorder; Leptin; Child; Adipokines; Biomarkers
PubMed: 38951775
DOI: 10.1186/s12888-024-05936-4 -
Journal of Psychiatric Research Jan 2024Leptin and insulin-like growth factor-1 (IGF-1) may play a role in clinical identification of post-stroke depression (PSD). Here, eight databases (including CNKI,... (Meta-Analysis)
Meta-Analysis Review
Leptin and insulin-like growth factor-1 (IGF-1) may play a role in clinical identification of post-stroke depression (PSD). Here, eight databases (including CNKI, Wanfang, SinoMed, VIP, PubMed, the Cochrane Library, Embase, and the Web of Science) were employed to search for studies on serum leptin and insulin-like growth factor-1 expression levels in patients with PSD. In total, 13 articles were included, of which 6 studies investigated the expression level of serum leptin in patients with PSD, 7 studies explored the serum IGF-1 in PSD patients. Then, the RevMan 5.4 software was used for meta-analysis. The results showed that serum leptin levels were significantly higher in PSD patients than in patients without PSD (SMD = 1.54, 95% CI: 0.84, 2.23; P = 0.006). The result of subgroup analysis showed that the serum leptin levels in PSD patients were significantly higher than those without PSD in acute phase (SMD = 1.38, 95% CI: 0.04, 2.71; P = 0.04), subacute phase (SMD = 2.31, 95% CI: 0.88, 3.73; P = 0.001), and chronic phase (SMD = 1.02, 95% CI: 0.43, 1.60; P = 0.0007); There was no significant difference in serum IGF-1 level between PSD patients and patients without PSD (SMD = 0.49, 95% CI: -0.55, 1.52; P = 0.36). Moreover, the subgroup analysis also showed that there was no statistical difference in acute stage (SMD = 0.36, 95% CI: 0.89, 1.60; P = 0.57). Our study provides evidence to prove that serum leptin level has potential clinical application value as biomarkers for identifying PSD.
Topics: Humans; Biomarkers; Depression; Insulin-Like Growth Factor I; Insulin-Like Peptides; Leptin; Stroke
PubMed: 38091723
DOI: 10.1016/j.jpsychires.2023.12.006 -
Archives of Medical Research Feb 2024Fibrates are widely used in the treatment of dyslipidemia and associated metabolic abnormalities; however, their effects on adipokines are unclear. (Meta-Analysis)
Meta-Analysis
BACKGROUND
Fibrates are widely used in the treatment of dyslipidemia and associated metabolic abnormalities; however, their effects on adipokines are unclear.
AIM OF THE STUDY
This meta-analysis of clinical trials aimed to evaluate the effect of fibrates on circulating adipokine levels.
METHODS
Only randomized controlled trials investigating the impact/effect of fibrate treatment on circulating adipokine levels were included from searches in PubMed-Medline, SCOPUS, ClinicalTrials.gov, Web of Science, and Google Scholar databases. A random effects model and the generic inverse variance method were used for the meta-analysis. Sensitivity analysis was conducted using the leave-one-out method.
RESULTS
This meta-analysis of 22 clinical trials showed a significant reduction on/in leptin (WMD: -1.58 ng/mL, 95% CI: -2.96, -0.20, p = 0.02, I = 0%), plasminogen activator inhibitor-1 (PAI-1) (WMD: -13.86 ng/mL, 95% CI: -26.70, -1.03, p = 0.03, I = 99%), and visfatin (WMD: -1.52 ng/mL, 95% CI: -2.49, -0.56, p = 0.002, I = 0%) after fibrate therapy; no significant effect was observed on adiponectin (WMD: -0.69 µg/ml, 95% CI: -1.40, 0.02, p = 0.06, I = 83%) and resistin (WMD: -2.27 ng/mL, 95% CI: -7.11, 2.57, p = 0.36, I = 0%). The sensitivity analysis was robust only for visfatin, while the effect size was sensitive to one arm for leptin, four for adiponectin, and two for PAI-1.
CONCLUSION
This meta-analysis showed that fibrate treatment significantly improves adipokine levels with a decrease in leptin, PAI-1, and visfatin, suggesting potential additional clinical therapeutic benefits through/of fibrate treatment on adipose tissue.
Topics: Leptin; Fibric Acids; Adipokines; Plasminogen Activator Inhibitor 1; Nicotinamide Phosphoribosyltransferase; Adiponectin; Randomized Controlled Trials as Topic
PubMed: 38266418
DOI: 10.1016/j.arcmed.2024.102957 -
BMC Gastroenterology Mar 2024Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), is a chronic relapsing-remitting systemic disease of the gastrointestinal... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), is a chronic relapsing-remitting systemic disease of the gastrointestinal tract with rising incidence. Studies have shown that adipocytes play a crucial role in patients with IBD by actively participating in systemic immune responses. The present study was designed to investigate the correlation between the circulatory levels of resistin, as an adipokine, and active and remission phases of IBD in comparison with healthy controls.
METHODS
Relevant articles were retrieved from PubMed, Embase, the Web of Science, and Scopus from inception until June 2023. Estimation of the standardized mean difference (SMD) and 95% confidence interval (CI) for comparison of plasma/serum resistin levels between IBD patients, patients in remission, and healthy controls were conducted through random-effect meta-analysis.
RESULTS
A total of 19 studies were included, assessing 1836 cases. Meta-analysis indicated that generally, serum/plasma resistin levels were higher in IBD patients in comparison with healthy controls (SMD 1.33, 95% CI 0.58 to 2.08, p-value < 0.01). This was true for each of the UC and CD separate analyses, as well. Moreover, it was shown that higher serum/plasma resistin levels were detected in the active phase of IBD than in the remission phase (SMD 1.04, 95% CI 0.65 to 1.42, p-value = 0.01). Finally, higher serum/plasma resistin levels were found in the remission phase compared to healthy controls (SMD 0.60, 95% CI 0.15 to 1.06, p-value < 0.01).
CONCLUSION
The results of this systematic review and meta-analysis support the conclusion that circulating resistin levels are increased in IBD (both UC and CD). Also, higher resistin levels were recorded in the remission phase of IBD in comparison with healthy controls. This indicates that further studies may provide valuable insights into the role of resistin in the pathogenesis of IBD.
Topics: Humans; Resistin; Inflammatory Bowel Diseases; Colitis, Ulcerative; Crohn Disease
PubMed: 38486190
DOI: 10.1186/s12876-024-03199-7 -
BMC Endocrine Disorders Mar 2024Prior studies reported that elevated asprosin level was associated with obesity in adults and animal models. However, the relationship between asprosin level and... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Prior studies reported that elevated asprosin level was associated with obesity in adults and animal models. However, the relationship between asprosin level and children with obeisty remains controversial. The aim of our analysis was to systematically review available literatures linking asprosin and children with obesity for a comprehensive understanding of the relationship between circulating asprosin level and obesity in children.
METHODS
Eight databases were gleaned for studies published up to January 2024. Standard mean difference with 95% confidence interval (CI) and Fisher's Z transformation was calculated to evaluate the relationship between asprosin level and children with obesity using the Review Manager 5.4 Software. Other indicators were measured via mean difference with 95% CI.
RESULTS
Six observational studies were included both in systematic review and meta-analysis. The current evidence indicated that no significant difference was observed in the level of circulating asprosin between the children with and without obesity (SMD = 0.37; 95% CI:-0.22-0.95, p = 0.22). However, Fisher's Z transformation suggested the positive association of circulating asprosin levels and clinical index measuring the degree of obesity: total cholesterol (Fisher's Z: 0.11, 95% CI: 0.02-0.20, p = 0.02).
CONCLUSIONS
Circulating asprosin level was not independently related to childhood obesity currently. More rigorous longitudinal researches were required to disentangle the causations. However, the positive association of asprosin levels and total cholesterol indicated that asprosin might get involved in the lipid-metabolism of childhood obesity, asprosin might be a prospective bio-index and targeted treatment of total cholesterol metabolism besides the role of glucogenic and orexigenic.
TRIAL REGISTRATION
Prospero ID: CRD42023426476.
Topics: Adult; Animals; Child; Humans; Cholesterol; Fibrillin-1; Glucose; Pediatric Obesity; Prospective Studies
PubMed: 38475734
DOI: 10.1186/s12902-024-01565-w