Association between circulating microRNAs 486, 146b and 15b and serum betatrophin levels in obese; type 2 diabetic and non-diabetic children

MicroRNA-29a and microRNA-122 expressions and other inflammatory markers among obese children with diabetes

OBJECTIVES

This study was conducted to study the expression of both microRNA-29a and microRNA-122, and serum levels of sestrin-2, interleukin-6 (IL-6), and other inflammatory markers among obese children with/and without diabetes mellitus.

METHODS

One hundred obese children with diabetes in addition to 100 age- and sex-matched obese children without diabetes, and 100 age- and sex-matched apparently healthy children were included in the study. Expressions of both microRNA-29a and microRNA-122, and serum levels of sestrin-2, IL-6, tumor necrosis factor-α (TNF-α), and high sensitive-CRP (hsCRP) were measured for all included study populations.

RESULTS

Study results showed that the expressions of both microRNA-29a and microRNA-122, serum levels of IL-6, TNF-α, and hsCRP were significantly higher among obese children with diabetes in comparison to both obese children without diabetes and healthy children. In contrast, serum sestrin level was significantly low among obese children with diabetes in comparison to the other study populations. Expressions of both microRNA-29a and microRNA-122 were correlated with waist circumference, BMI, total cholesterol, triglycerides, LDL-cholesterol, HbA1c, c-peptide, glucose, insulin, homeostatic model assessment-insulin resistance (HOMA-IR), IL-6, hsCRP, and TNF-α among obese children with diabetes. However, serum sestrin-2 level was correlated inversely with these parameters. Higher expressions of both microRNA-29a and microRNA-122 among obese children either with or without diabetes mellitus (DM) can suggest their roles in the development of obesity among children.

CONCLUSIONS

The study results can hypothesize that down-regulation of these micro-RNAs may solve this health problem with its sequelae, a hypothesis that needs more studies.

Peripheral blood mononuclear cells-expressed miRNA profiles derived from children with metabolic-associated fatty liver disease and insulin resistance

BACKGROUND

miRNA have been proposed as potential biomarkers of metabolic diseases.

OBJECTIVES

To identify potential miRNA biomarkers of early metabolic-associated fatty liver disease (MAFLD) and/or insulin resistance (IR) in preadolescent children.

METHODS

A total of 70 preadolescents, aged 8.5-12 years old participated in the study. Hepatic fat was assessed by magnetic resonance imaging. Fasting blood biochemical parameters were measured and HOMA-IR calculated. Peripheral blood mononuclear cells (PBMC)-derived miRNA profiles associated with MAFLD (≥5.5% hepatic fat) and IR (HOMA-IR ≥2.5) were identified using untargeted high-throughput miRNAs sequencing (RNA-seq).

RESULTS

A total of 2123 PBMC-derived miRNAs were identified in children with (21.4%) or without MAFLD. Among them, hsa-miR-143-3p, hsa-miR-142-5p and hsa-miR-660-5p were up-regulated, and p-hsa-miR-247, hsa-let-7a-5p and hsa-miR-6823-3p down-regulated. Importantly, children with MAFLD had consistently higher miR-660-5p expression levels than their peers without it (p < 0.01), regardless of weight status. A total of 2124 PBMC-derived miRNA were identified in children with IR (28.6%) versus children without IR, where thirteen of them were dysregulated (p < 0.05) in children with IR. In addition, children with IR showed higher levels of miR-374a-5p and miR-190a-5p (p < 0.01) and lower levels of miR-4284 and miR-4791 (p < 005), than their peers without IR in both the whole sample and in those with overweight or obesity.

CONCLUSIONS

Our study results suggest circulating miR-660-5p as a potential biomarker of the presence of MAFLD in preadolescent children while circulating miR-320a, miR-142-3p, miR-190a-5p, miR-374a-5p and let-7 family miRNAs could serve as potential biomarkers of IR in children.

The Roles and Associated Mechanisms of Adipokines in Development of Metabolic Syndrome

Metabolic syndrome is a cluster of metabolic indicators that increase the risk of diabetes and cardiovascular diseases. Visceral obesity and factors derived from altered adipose tissue, adipokines, play critical roles in the development of metabolic syndrome. Although the adipokines leptin and adiponectin improve insulin sensitivity, others contribute to the development of glucose intolerance, including visfatin, fetuin-A, resistin, and plasminogen activator inhibitor-1 (PAI-1). Leptin and adiponectin increase fatty acid oxidation, prevent foam cell formation, and improve lipid metabolism, while visfatin, fetuin-A, PAI-1, and resistin have pro-atherogenic properties. In this review, we briefly summarize the role of various adipokines in the development of metabolic syndrome, focusing on glucose homeostasis and lipid metabolism.

Serum microRNA-486-5p expression in obese Egyptian children and its possible association with fatty liver

AIMS

Several microRNAs (miRNAs) are involved in regulating the process of adipogenesis. White adipose tissue is a major source for these miRNAs. We aimed to evaluate the expression of miR-486-5p in children with obesity and its possible association with nonalcoholic fatty liver disease (NAFLD).

METHOD

This case-control study included 100 obese and overweight children and 100 normal-weight children of matched age and sex. All children were subjected to anthropometric measurements and evaluation of miR-486-5p expression levels using the SYBR green-based real-time RT-PCR technique.

RESULTS

Obese children showed significantly up-regulated miR-486-5p gene expression (p value < 0.001) when compared to control group. MiR-486-5p gene expression showed significant positive correlation with weight (r = 0.924), BMI (r = 0.497), waist circumference (r = 0.387), fat mass (r = 0.361), LDL(r = 0.351), TG (r = 0.867), TC (r = 0.875) and presence of fatty liver (r = 0.760). The best cutoff value of miR-486-5p gene expression in the prediction of obesity was 0.44 with AUC 0.736 that has a sensitivity 60% and specificity 90%, CONCLUSION: The serum level of the miR-486-5p gene is up-regulated in obese and overweight children and might be an independent predictor for obesity and fatty liver susceptibility.

Investigation of the levels of circulating miR-29a, miR-122, sestrin 2 and inflammatory markers in obese children with/without type 2 diabetes: a case control study

AIM

The present work investigated serum levels of miR-29a, miR-122 and sestrin2 in obese children with/without type-2-diabetes mellitus (T2DM), and their correlations with inflammatory, metabolic and anthropometric parameters.

METHODS

The study included 298 children, divided into: G1 (control, n = 136), G2 (obese without diabetes, n = 90) and G3 (obese with T2DM, n = 72). Metabolic and anthropometric parameters, miR-29a, miR-122 relative expressions, and sestrin2, high sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) levels were measured by their specific methods. The data was processed and analyzed by SPSS V.26 using the corresponding tests. After testing the variables' normality, Kruskal-Wallis one-way-ANOVA, Spearman correlations coefficient were used.

RESULTS

Significant higher serum miR-29a, miR-122, IL-6, hsCRP and TNF-α and lower sestrin2 levels were found in G2 and G3 than G1 and in G3 than G2 (p= > 0.001 for all). Especially in G3, miR-29a and miR-122 levels correlated positively while sestrin2 levels correlated negatively with waist circumference and BMI percentiles, serum levels of LDL-cholesterol, triacylglycerol, total cholesterol, HbA1c%, glucose, insulin, c-peptide, homeostatic model assessment-insulin resistance (HOMA-IR), IL-6, hsCRP and TNF-α.

CONCLUSION

The change in the serum miR-29a, miR-122 and sestrin2 levels in obese children with/without T2DM may suggest a possible role of these biomarkers in the pathogenesis of childhood obesity and their accompanied complications e.g. inflammations and T2DM. Also, further studies are required to test drugs that antagonize the action miR-29a and miR-122 or upregulate sestrin2 in the management of these cases.

High fructose exposure modifies the amount of adipocyte-secreted microRNAs into extracellular vesicles in supernatants and plasma

Background

High fructose exposure induces metabolic and endocrine responses in adipose tissue. Recent evidence suggests that microRNAs in extracellular vesicles are endocrine signals secreted by adipocytes. Fructose exposure on the secretion of microRNA by tissues and cells is poorly studied. Thus, the aim of this study was to evaluate the effect of fructose exposure on the secretion of selected microRNAs in extracellular vesicles from 3T3-L1 cells and plasma from Wistar rats.

Methods

3T3-L1 cells were exposed to 550 µM of fructose or standard media for four days, microRNAs levels were determined in extracellular vesicles of supernatants and cells by RT-qPCR. Wistar rats were exposed to either 20% fructose drink or tap water for eight weeks, microRNAs levels were determined in extracellular vesicles of plasma and adipose tissue by RT-qPCR.

Results

This study showed that fructose exposure increased the total number of extracellular vesicles released by 3T3-L1 cells (p = 0.0001). The levels of miR-143-5p were increased in extracellular vesicles of 3T3-L1 cells exposed to fructose (p = 0.0286), whereas miR-223-3p levels were reduced (p = 0.0286). Moreover, in plasma-derived extracellular vesicles, miR-143-5p was higher in fructose-fed rats (p = 0.001), whereas miR-223-3p (p = 0.022), miR-342-3p (p = 0.0011), miR-140-5p (p = 0.0129) and miR-146b-5p (p = 0.0245) were lower.

Conclusion

Fructose exposure modifies the levels of microRNAs in extracellular vesicles in vitro and in vivo. In particular, fructose exposure increases miR-143-5p, while decreases miR-223-3p and miR-342-3p.