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Nutrients Aug 2023This paper presents a systematic review of studies investigating the effects of fatty acid supplementation in potentially preventing and treating sarcopenia. PubMed,... (Review)
Review
This paper presents a systematic review of studies investigating the effects of fatty acid supplementation in potentially preventing and treating sarcopenia. PubMed, Embase, and Web of Science databases were searched using the keywords 'fatty acid' and 'sarcopenia'. Results: A total of 14 clinical and 11 pre-clinical (including cell and animal studies) studies were included. Of the 14 clinical studies, 12 used omega-3 polyunsaturated fatty acids (PUFAs) as supplements, 1 study used ALA and 1 study used CLA. Seven studies combined the use of fatty acid with resistant exercises. Fatty acids were found to have a positive effect in eight studies and they had no significant outcome in six studies. The seven studies that incorporated exercise found that fatty acids had a better impact on elderlies. Four animal studies used novel fatty acids including eicosapentaenoic acid, trans-fatty acid, and olive leaf extraction as interventions. Three animal and four cell experiment studies revealed the possible mechanisms of how fatty acids affect muscles by improving regenerative capacity, reducing oxidative stress, mitochondrial and peroxisomal dysfunctions, and attenuating cell death. Conclusion: Fatty acids have proven their value in improving sarcopenia in pre-clinical experiments. However, current clinical studies show controversial results for its role on muscle, and thus the mechanisms need to be studied further. In the future, more well-designed randomized controlled trials are required to assess the effectiveness of using fatty acids in humans.
Topics: Animals; Humans; Muscles; Cell Death; Databases, Factual; Dietary Supplements; Eicosapentaenoic Acid; Fatty Acids; Sarcopenia
PubMed: 37630803
DOI: 10.3390/nu15163613 -
Frontiers in Endocrinology 2023The relationships of the rs17782313 polymorphism near melanocortin 4 receptor gene (MC4R) and the rs8192678 polymorphism in peroxisome proliferator-activated receptor... (Meta-Analysis)
Meta-Analysis
The rs17782313 polymorphism near MC4R gene confers a high risk of obesity and hyperglycemia, while PGC1α rs8192678 polymorphism is weakly correlated with glucometabolic disorder: a systematic review and meta-analysis.
BACKGROUND
The relationships of the rs17782313 polymorphism near melanocortin 4 receptor gene (MC4R) and the rs8192678 polymorphism in peroxisome proliferator-activated receptor gamma coactivator 1 alpha gene (PGC1α) with metabolic abnormalities have been explored in many populations around the world, but the findings were not all consistent and sometimes even a bit contradictory.
METHODS
Electronic databases including Medline, Scopus, Embase, Web of Science, CNKI and Google Scholar were checked for studies that met the inclusion criteria. Data were carefully extracted from eligible studies. Standardized mean differences (SMDs) were calculated by using a random-effects model to examine the differences in the indexes of obesity, glucometabolic disorder and dyslipidemia between the genotypes of the rs17782313 and rs8192678 polymorphisms. Cochran's Q-statistic test and Begg's test were employed to identify heterogeneity among studies and publication bias, respectively.
RESULTS
Fifty studies (58,716 subjects) and 51 studies (18,660 subjects) were respectively included in the pooled meta-analyses for the rs17782313 and rs8192678 polymorphisms. The C-allele carriers of the rs17782313 polymorphism had a higher average level of body mass index (SMD = 0.21 kg/m, 95% confidence interval [95% CI] = 0.12 to 0.29 kg/m, < 0.001), waist circumference (SMD = 0.14 cm, 95% CI = 0.06 to 0.23 cm, < 0.001) and blood glucose (SMD = 0.09 mg/dL, 95% CI = 0.02 to 0.16 mg/dL, = 0.01) than the TT homozygotes. Regarding the rs8192678 polymorphism, no significant associations with the indexes of obesity, glucometabolic disorder and dyslipidemia were detected. However, significant correlations between the rs8192678 polymorphism and multiple glucometabolic indexes were observed in subgroup analyses stratified by sex, age, ethnicity and health status.
CONCLUSION
The meta-analysis demonstrates that the C allele of the MC4R rs17782313 polymorphism confers a higher risk of obesity and hyperglycemia, and the PGC1α rs8192678 polymorphism is weakly correlated with glucometabolic disorder. These findings may partly explain the relationships between these variants and diabetes as well as cardiovascular disease.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/, identifier CRD42022373543.
Topics: Humans; Alleles; Genotype; Hyperglycemia; Obesity; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Receptor, Melanocortin, Type 4
PubMed: 37621650
DOI: 10.3389/fendo.2023.1210455 -
Nutrients Mar 2023The inter-individual variability of metabolic response to foods may be partly due to genetic variation. This systematic review aims to assess the associations between... (Review)
Review
The inter-individual variability of metabolic response to foods may be partly due to genetic variation. This systematic review aims to assess the associations between genetic variants and glucose response to an oral glucose tolerance test (OGTT). Three databases (PubMed, Web of Science, Embase) were searched for keywords in the field of genetics, OGTT, and metabolic response (PROSPERO: CRD42021231203). Inclusion criteria were available data on single nucleotide polymorphisms (SNPs) and glucose area under the curve (gAUC) in a healthy study cohort. In total, 33,219 records were identified, of which 139 reports met the inclusion criteria. This narrative synthesis focused on 49 reports describing gene loci for which several reports were available. An association between SNPs and the gAUC was described for 13 gene loci with 53 different SNPs. Three gene loci were mostly investigated: (), (), and (). In most reports, the associations were not significant or single findings were not replicated. No robust evidence for an association between SNPs and gAUC after an OGTT in healthy persons was found across the identified studies. Future studies should investigate the effect of polygenic risk scores on postprandial glucose levels.
Topics: Humans; Glucose Tolerance Test; Diabetes Mellitus, Type 2; Genotype; Risk Factors; Glucose; Polymorphism, Single Nucleotide; Genetic Predisposition to Disease
PubMed: 37049537
DOI: 10.3390/nu15071695 -
Biomedicines Jan 2023Diabetes mellitus (DM) is known to be a risk factor for dementia, especially in the elderly population, and close associations between diabetes and Alzheimer disease... (Review)
Review
Diabetes mellitus (DM) is known to be a risk factor for dementia, especially in the elderly population, and close associations between diabetes and Alzheimer disease (AD) have been determined. Peroxisome proliferator-activated receptor-gamma (PPAR-γ) agonists are insulin-sensitising drugs. In addition to their anti-diabetic properties, their effectiveness in preventing and decreasing cognitive impairment are the most recent characteristics that have been studied. For this study, we conducted a systematic review and meta-analysis to critically analyse and evaluate the existing data on the effects of PPAR-γ agonist therapy on the cognitive status of patients. For this purpose, we first analysed both early intervention and later treatment with PPAR-γ agonists, according to the disease status. The involved studies indicated that early PPAR-γ agonist intervention is beneficial for patients and that high-dose PPAR-γ therapy may have a better clinical effect, especially in reversing the effects of cognitive impairment. Furthermore, the efficacy of pioglitazone (PIO) seems to be promising, particularly for patients with comorbid diabetes. PIO presented a better clinical curative effect and safety, compared with rosiglitazone (RSG). Thus, PPAR-γ agonists play an important role in the inflammatory response of AD or DM patients, and clinical therapeutics should focus more on relevant metabolic indices.
PubMed: 36830783
DOI: 10.3390/biomedicines11020246 -
The Cochrane Database of Systematic... Jan 2023Peroxisome proliferator-activated receptor gamma (PPAR-γ) agonists are insulin-sensitising drugs used for the treatment of insulin resistance. In addition to lowering... (Review)
Review
BACKGROUND
Peroxisome proliferator-activated receptor gamma (PPAR-γ) agonists are insulin-sensitising drugs used for the treatment of insulin resistance. In addition to lowering glucose in diabetes, these drugs may also protect against hyperlipidaemia and arteriosclerosis, which are risk factors for stroke. This is an update of a review first published in January 2014 and subsequently updated in December 2017 and October 2019.
OBJECTIVES
To assess the efficacy and safety of PPAR-γ agonists in the secondary prevention of stroke and related vascular events for people with stroke or transient ischaemic attack (TIA).
SEARCH METHODS
We searched the Cochrane Stroke Group Trials Register (1 January 2022), the Cochrane Central Register of Controlled Trials (CENTRAL; 2021, Issue 12), MEDLINE (1949 to 1 January 2022), Embase (1980 to 1 January 2022), CINAHL (1982 to 1 January 2022), AMED (1985 to 1 January 2022), and 11 Chinese databases (1 January 2022). In an effort to identify further published, unpublished, and ongoing trials, we searched ongoing trials registers, reference lists, and relevant conference proceedings, and contacted authors and pharmaceutical companies. We did not impose any language restrictions.
SELECTION CRITERIA
We included randomised controlled trials (RCTs) evaluating PPAR-γ agonists versus placebo for the secondary prevention of stroke and related vascular events in people with stroke or TIA, with the outcomes of recurrent stroke, vascular events, and adverse events.
DATA COLLECTION AND ANALYSIS
Two review authors independently screened the titles and abstracts of identified records, selected studies for inclusion, extracted eligible data, cross-checked the data for accuracy, and assessed methodological quality and risk of bias. We evaluated the certainty of evidence for each outcome using the GRADE approach.
MAIN RESULTS
We identified five RCTs with 5039 participants; two studies had a low risk of bias for all domains. Four studies evaluated the drug pioglitazone, and one study evaluated rosiglitazone. The participants in different studies were heterogeneous. Recurrent stroke Three studies evaluated the number of participants with recurrent stroke (4979 participants, a single study contributing 3876 of these). Peroxisome proliferator-activated receptor gamma agonists probably reduce the recurrence of stroke compared with placebo (risk ratio (RR) 0.66, 95% confidence interval (CI) 0.44 to 0.99; moderate-certainty evidence). Adverse events Evidence that adverse events occurred more frequently in participants treated with PPAR-γ agonists when compared with placebo was uncertain due to wide confidence intervals and high levels of statistical heterogeneity: risk difference 10%, 95% CI -8% to 28%; low-certainty evidence). Data were available on additional composite outcomes reflecting serious vascular events (all-cause death and other major vascular events; all-cause mortality, non-fatal myocardial infarction or non-fatal stroke) from one study in 984 people. This study provided low-certainty evidence that PPAR-γ agonists led to fewer events (data not meta-analysed). Vascular events Peroxisome proliferator-activated receptor gamma agonists given over a mean duration of 34.5 months in a single trial of 984 participants may reduce serious vascular events expressed as a composite outcome of total events of cardiovascular death, non-fatal myocardial infarction or non-fatal stroke (RR 0.73, 95% CI 0.54 to 0.99; low-certainty evidence). Other outcomes One study in 20 people measured insulin sensitivity, and one study in 40 people measured the ubiquitin-proteasome activity in carotid plaques. Our confidence in the improvements observed with PPAR-γ agonists were limited by small sample sizes and risk of bias. None of the studies reported the number of participants with disability due to vascular events or improvement in quality of life.
AUTHORS' CONCLUSIONS
Peroxisome proliferator-activated receptor gamma agonists probably reduce recurrent stroke and total events of cardiovascular death, non-fatal myocardial infarction or non-fatal stroke, and may improve insulin sensitivity and the stabilisation of carotid plaques. Their effects on adverse events are uncertain. Our conclusions should be interpreted with caution considering the small number and the quality of the included studies. Further well-designed, double-blind RCTs with large samples are required to assess the efficacy and safety of PPAR-γ agonists in the secondary prevention of stroke and related vascular events in people with stroke or TIA.
Topics: Humans; Ischemic Attack, Transient; PPAR gamma; Insulin Resistance; Stroke; Myocardial Infarction; Randomized Controlled Trials as Topic
PubMed: 36625492
DOI: 10.1002/14651858.CD010693.pub6 -
Nutrients Dec 2022Genetic components may play an important role in the regulation of nutrient and energy metabolism. In the presence of specific genetic variants, metabolic dysregulation... (Review)
Review
Genetic components may play an important role in the regulation of nutrient and energy metabolism. In the presence of specific genetic variants, metabolic dysregulation may occur, especially in relation to the processes of digestion, assimilation, and the physiological utilization of nutrients supplied to the body, as well as the regulation of various metabolic pathways and the balance of metabolic changes, which may consequently affect the effectiveness of applied reduction diets and weight loss after training. There are many well-documented studies showing that the presence of certain polymorphic variants in some genes can be associated with specific changes in nutrient and energy metabolism, and consequently, with more or less desirable effects of applied caloric reduction and/or exercise intervention. This systematic review focused on the role of genes encoding peroxisome proliferator-activated receptors (PPARs) and their coactivators in nutrient and energy metabolism. The literature review prepared showed that there is a link between the presence of specific alleles described at different polymorphic points in genes and various human body characteristics that are crucial for the efficacy of nutritional and/or exercise interventions. Genetic analysis can be a valuable element that complements the work of a dietitian or trainer, allowing for the planning of a personalized diet or training that makes the best use of the innate metabolic characteristics of the person who is the subject of their interventions.
Topics: Humans; Peroxisome Proliferator-Activated Receptors; Nutrients; Energy Metabolism; Diet; Alleles
PubMed: 36558537
DOI: 10.3390/nu14245378 -
Nutrients Nov 2022The health benefits of omega-3 fatty acid (FA) supplementation on inflammatory gene expression (IGE) and multiple sclerosis (MS) are becoming more evident. However, an... (Meta-Analysis)
Meta-Analysis Review
The health benefits of omega-3 fatty acid (FA) supplementation on inflammatory gene expression (IGE) and multiple sclerosis (MS) are becoming more evident. However, an overview of the results from randomized controlled trials is lacking. This study aimed to conduct a meta-analysis to evaluate the effect of omega-3 fatty acid intake on MS (based on the criteria of the Expanded Disability Status Scale (EDSS)) and inflammatory gene expression (IGE). A search was conducted of PubMed, EMBASE, and Web of Science for cohort studies published from the inception of the database up to May 2022 that assessed the associations of omega-3 polyunsaturated fatty acids (n-3 PUFAs), docosahexaenoic acid (DHA), α-linolenic acid (ALA), and eicosapentaenoic acid (EPA) with EDSS and inflammatory gene expression (peroxisome proliferator-activated receptor gamma (PPAR-γ), tumor necrosis factor-alpha (TNF-α), interleukin-1 (IL-1), interleukin-6 (IL-6), and interleukin-8 (IL-8)) outcomes. For the highest vs. lowest comparison, the relative risk (RR) estimates with a 95% confidence interval (CI) were pooled using the random-effect model. In total, 13 cohort studies with 1353 participants were included in the meta-analysis during periods of 3 to 144 weeks. A significant inverse relationship was found between DHA and EDSS scores (RR: 1.05; 95% CI: 0.62, 1.48; p < 0.00001). Our results also showed that omega-3 FAs significantly upregulated the gene expression of PPAR-γ (RR: 0.95; 95% CI: 0.52, 1.38; p < 0.03) and downregulated the expression of TNF-α (RR: −0.15; 95% CI: −0.99, 0.70; p < 0.00001) and IL-1 (RR: −0.60; 95% CI: −1.02, −0.18; p < 0.003). There was no clear evidence of publication bias with Egger’s tests for inflammatory gene expression (p = 0.266). Moreover, n-3 PUFAs and EPA were not significantly associated with EDSS scores (p > 0.05). In this meta-analysis of cohort studies, blood omega-3 FA concentrations were inversely related to inflammatory gene expression (IGE) and EDSS score, which indicates that they may hold great potential markers for the diagnosis, prognosis, and management of MS. However, further clinical trials are required to confirm the potential effects of the omega-3 FAs on MS disease management.
Topics: Humans; Multiple Sclerosis; Tumor Necrosis Factor-alpha; Peroxisome Proliferator-Activated Receptors; Fatty Acids, Omega-3; Eicosapentaenoic Acid; Docosahexaenoic Acids; Interleukin-1; Gene Expression; Immunoglobulin E
PubMed: 36364885
DOI: 10.3390/nu14214627 -
Frontiers in Endocrinology 2022The relationships between the rs1801282 and rs3856806 polymorphisms in nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) gene and obesity... (Meta-Analysis)
Meta-Analysis
G Allele of the rs1801282 Polymorphism in PPARγ Gene Confers an Increased Risk of Obesity and Hypercholesterolemia, While T Allele of the rs3856806 Polymorphism Displays a Protective Role Against Dyslipidemia: A Systematic Review and Meta-Analysis.
BACKGROUND
The relationships between the rs1801282 and rs3856806 polymorphisms in nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) gene and obesity indexes as well as serum lipid levels have been extensively investigated in various studies, but the results were inconsistent and even contradictory.
METHODS
PubMed, Google Scholar, Embase, Cochrane Library, Web of Science, Wanfang, CNKI and VIP databases were searched for eligible studies. The random-effTPDEects model was used, and standardized mean difference (SMD) with 95% confidence interval (CI) was calculated to estimate the differences in obesity indexes and serum lipid levels between the subjects with different genotypes in a dominant model. Heterogeneity among studies was assessed by Cochran's x-based Q-statistic test. Publication bias was identified by using Begg's test.
RESULTS
One hundred and twenty studies (70,317 subjects) and 33 studies (18,353 subjects) were identified in the analyses for the rs1801282 and rs3856806 polymorphisms, respectively. The G allele carriers of the rs1801282 polymorphism had higher levels of body mass index (SMD = 0.08 kg/m, 95% CI = 0.04 to 0.12 kg/m, < 0.001), waist circumference (SMD = 0.12 cm, 95% CI = 0.06 to 0.18 cm, < 0.001) and total cholesterol (SMD = 0.07 mmol/L, 95% CI = 0.02 to 0.11 mmol/L, < 0.01) than the CC homozygotes. The T allele carriers of the rs3856806 polymorphism had lower levels of low-density lipoprotein cholesterol (SMD = -0.09 mmol/L, 95% CI = -0.15 to -0.03 mmol/L, < 0.01) and higher levels of high-density lipoprotein cholesterol (SMD = 0.06 mmol/L, 95% CI = 0.02 to 0.10 mmol/L, < 0.01) than the CC homozygotes.
CONCLUSIONS
The meta-analysis suggests that the G allele of the rs1801282 polymorphism confers an increased risk of obesity and hypercholesterolemia, while the T allele of the rs3856806 polymorphism displays a protective role against dyslipidemia, which can partly explain the associations between these polymorphisms and cardiovascular disease.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/, identifier [CRD42022319347].
Topics: Alleles; Cholesterol, HDL; Dyslipidemias; Humans; Hypercholesterolemia; Obesity; PPAR gamma; Polymorphism, Single Nucleotide
PubMed: 35846293
DOI: 10.3389/fendo.2022.919087 -
Frontiers in Physiology 2022Blood flow restriction (BFR) exercise may be a potential exercise program to promote angiogenesis. This review aims to compare the effects of exercise with and without...
BACKGROUND
Blood flow restriction (BFR) exercise may be a potential exercise program to promote angiogenesis. This review aims to compare the effects of exercise with and without BFR on angiogenesis-related factors in skeletal muscle among healthy adults.
METHODOLOGY
Searches were made in Web of Science, Scopus, PubMed, and EBSCO databases from January 2001 to June 2021. Studies were screened, quality was evaluated, and data were extracted. The review protocol was registered at PROSPERO (PROSPERO registration number: CRD42021261367). Standardized mean differences (SMD) of vascular endothelial growth factor (VEGF), vascular endothelial growth factor receptor 2 (VEGFR-2), hypoxia inducible factor 1α (HIF-1α), peroxisome proliferator-activated receptorγcoactivator-1α (PGC-1α) and endothelial nitric oxide synthase (eNOS) were analyzed using Revman 5.4 software with a 95% confidence interval (95% CI).
RESULTS
Ten studies fulfilled the inclusion criteria with a total of 75 participants for BFR group and 77 for CON group. BFR exercise elicits greater expression of VEGF (heterogeneity test, = 0.09, I = 44%; SMD, 0.93 [0.38, 1.48], < 0.05), VEGFR-2 (heterogeneity test, = 0.81, I = 0%; SMD, 0.64 [0.08, 1.21], < 0.05), HIF-1α (heterogeneity test, = 0.67, I = 0%; SMD, 0.43 [0.03, 0.82], < 0.05), PGC-1α (heterogeneity test, = 0.02, I = 54%; SMD, 0.74 [0.21, 1.28], < 0.05) and eNOS (heterogeneity test, = 0.88, I = 0%; SMD, 0.60 [0.04, 1.17], < 0.05) mRNA than non-BFR exercise. In the sub-group analysis, resistance exercise with BFR elicits greater expression of VEGF (heterogeneity test, = 0.36, I = 6%; SMD, 1.66 [0.97, 2.35], < 0.05) and HIF-1α (heterogeneity test, = 0.56, I = 0%; SMD, 0.51 [0.01, 1.02], < 0.05) mRNA than aerobic exercise with BFR.
CONCLUSION
Exercise with BFR elicited more angiogenesis-related factors mRNA expression than exercise without BFR, but not VEGF and PGC-1α protein expression. Therefore, BFR training may be a potential training program to improve vascular function.
SYSTEMATIC REVIEW REGISTRATION
[https://www.crd.york.ac.uk/prospero/], identifier [CRD42021261367].
PubMed: 35250618
DOI: 10.3389/fphys.2022.814965 -
Brain Sciences Jan 2022Antiseizure medications are the cornerstone pharmacotherapy for epilepsy. They are not devoid of side effects. In search for better-tolerated antiseizure agents,... (Review)
Review
Antiseizure medications are the cornerstone pharmacotherapy for epilepsy. They are not devoid of side effects. In search for better-tolerated antiseizure agents, cannabinoid compounds and other N-acylethanolamines not directly binding cannabinoid receptors have drawn significant attention. Among these, palmitoylethanolamide (PEA) has shown neuroprotective, anti-inflammatory, and analgesic properties. All studies examining PEA's role in epilepsy and acute seizures were systematically reviewed. Preclinical studies indicated a systematically reduced PEA tone accompanied by alterations of endocannabinoid levels. PEA supplementation reduced seizure frequency and severity in animal models of epilepsy and acute seizures, in some cases, similarly to available antiseizure medications but with a better safety profile. The peripheral-brain immune system seemed to be more effectively modulated by subchronic pretreatment with PEA, with positive consequences in terms of better responding to subsequent epileptogenic insults. PEA treatment restored the endocannabinoid level changes that occur in a seizure episode, with potential preventive implications in terms of neural damage. Neurobiological mechanisms for PEA antiseizure effect seemed to include the activation of the endocannabinoid system and the modulation of neuroinflammation and excitotoxicity. Although no human study was identified, there is ground for testing the antiseizure potential of PEA and its safety profile in human studies of epilepsy.
PubMed: 35053844
DOI: 10.3390/brainsci12010101