The effects of an acute exercise bout on GH and IGF-1 in prediabetic and healthy African Americans: A pilot study investigating gene expression

Multi-Tiered Assessment of Gene Expression Provides Evidence for Mechanisms That Underlie Risk for Type 2 Diabetes

Introduction

Integrated transcriptome and microRNA differential gene expression (DEG) analyses may help to explain type 2 diabetes (T2D) pathogenesis in at-risk populations. The purpose of this study was to characterize DEG in banked biospecimens from underactive adult participants who responded to a randomized clinical trial measuring the effects of lifestyle interventions on T2D risk factors. DEGs were further examined within the context of annotated biological pathways.

Methods

Participants (n = 52) in a previously completed clinical trial that assessed a 12-week behavioural intervention for T2D risk reduction were included. Participants who showed >6mg/dL decrease in fasting blood glucose were identified as responders. Gene expression was measured by RNASeq, and overrepresentation analysis within KEGG pathways and weighted gene correlation network analysis (WGCNA) were performed.

Results

No genes remained significantly differentially expressed after correction for multiple comparisons. One module derived by WGCNA related to body mass index was identified, which contained genes located in KEGG pathways related to known mechanisms underlying risk for T2D as well as pathways related to neurodegeneration and protein misfolding. A network analysis showed indirect connections between genes in this module and islet amyloid polypeptide (IAPP), which has previously been hypothesized as a mechanism for T2D.

Discussion

We validated prior studies that showed pathways related to metabolism, inflammation/immunity, and endocrine/hormone function are related to risk for T2D. We identified evidence for new potential mechanisms that include protein misfolding. Additional studies are needed to determine whether these are potential therapeutic targets to decrease risk for T2D.

Dynamic of irisin secretion change after moderate-intensity chronic physical exercise on obese female

OBJECTIVES

Exercise is one of the beneficial mediators for the regulation and prevention of obesity through the role of irisin, so it potentially enhances metabolism health. This study aims to investigate the dynamic of irisin secrecy change after chronic exercise in obese females.

METHODS

Thirty-one female adolescents aged 20-22 years enrolled in the study and were given interventions aerobic, resistance, and a combination of aerobic and resistance training. The exercises were performed at moderate-intensity, for 35-40 min per session, and three times a week for four weeks. The measurement of irisin level, IGF-1 level, and bio-anthropometry was carried out before and after the four weeks of exercise. The bio-anthropometry measurement was carried out using seca mBCA 514, while the measurement of insulin-like growth factor 1 (IGF-1) and irisin was completed using an enzyme-linked immunosorbent assay (ELISA). The obtained data were analyzed using a one-way ANOVA test with 5 % significance.

RESULTS

Our results indicated higher dynamic of irisin and IGF-1 increases in the group with a combination of aerobic and resistance training exercises than the other two groups with a different exercise. Further, we also observed different dynamics of irisin and IGF-1 level increase (p<0.05). Besides, the irisin was also correlated with the IGF-1 and bio-anthropometric parameters (p<0.05).

CONCLUSIONS

The combination of aerobic and resistance training exercises is considered as the alternative for enhancing the dynamic of irisin and IGF-1 increase. Thus, it can be used to prevent and regulate obesity.

Physiological response of endurance exercise as a growth hormone mediator in adolescent women's

OBJECTIVES

Overweight status decreases the growth hormone (GH) secretion, thus, increasing the risk factors for medical complications. However, proper exercise is reported to enhance GH and affect the energy balance. Therefore, exercise is proclaimed to be an accurate and engaging therapy to increase GH in preventing overweight. This study aims to investigate the physiological response of exercise in mediating the increase of GH secretion in female adolescents.

METHODS

22 overweight women aged 19-20 years old, with maximal oxygen consumption of 27-35 mL/kg/min, were selected as sample size. They were divided into three groups, namely (CONT, n=7) Control, (MIEE, n=7) Moderate-intensity interval endurance exercise, and (MCEE, n=8) Moderate-intensity continuous endurance exercise. The exercise was carried out by running for 30-35 min using treadmills with an intensity of 60-70% HR_max. The blood sampling for GH examination was carried out four times before exercise, 10 min, 6 h, and 24 h after exercise. The enzyme-linked immunosorbent assay (ELISA) was used to measure the GH and IGF-1 levels. The data analysis was carried out using a one-way ANOVA test, with a significance level of 5%.

RESULTS

The results of the one-Way ANOVA test suggested a significantly different average GH and IGF-1 before and after the exercise between the three groups (CON, MIEE, and MCEE) (p≤0.05).

CONCLUSIONS

MCEE increases the GH and IGF-1 levels more considerably than MIEE. Therefore, exercise is a mediator to increase GH and IGF-1 secretion in overweight individuals. Exercise could be a viable therapy for overweight people.

Integrated computational approaches to screen gene expression data to determine key genes and therapeutic targets for type-2 diabetes mellitus

There is a rapid rise in cases of Type-2-diabetes mellitus (T2DM) globally, irrespective of the geography, ethnicity or any other variable factors. The molecular mechanisms that could cause the condition of T2DM need to be more thoroughly analysed to understand the clinical manifestations and to derive better therapeutic regimes. Tools in bioinformatics are used to trace out key gene elements and to identify the key causative gene elements and their possible therapeutic agents. Microarray datasets were retrieved from the Gene expression omnibus database and studied using R to derive different expressed gene (DEG) elements. With the comparison of the expressed genes with disease specific genes in DisGeNET, the final annotated genes were taken for analysis. Gene Ontology studies, Protein-protein interaction (PPI), Co-expression analysis, Gene-drug interactions were performed to scale down the hub genes and to identify the novelty across the genes analysed so far. In vivo and invitro analysis of key genes and the trace of interaction pathway is crucial to better understand the unique outcomes from the novel genes, forming the basis to understand the pathway that ends up causing T2DM. Afterwards, docking was executed enabling recognition of interacting residues involved in inhibition. The complex CCL5-265 and CD8A-40585 thus docked showed best results as is evident from its PCA analysis and MMGBSA calculation. There is now scope for deriving candidate drugs that could possibly detect personalized therapies for T2DM.