Effects of miR-152-Mediated Targeting of SOCS3 on Hepatic Insulin Resistance in Gestational Diabetes Mellitus Mice

Dietary modulation of microRNAs in insulin resistance and type 2 diabetes

The prevalence of type 2 diabetes is increasing worldwide. Various molecular mechanisms have been proposed to interfere with the insulin signaling pathway. Recent advances in proteomics and genomics indicate that one such mechanism involves the post-transcriptional regulation of insulin signaling by microRNA (miRNA). These noncoding RNAs typically induce messenger RNA (mRNA) degradation or translational repression by interacting with the 3' untranslated region (3'UTR) of target mRNA. Dietary components and patterns, which can either enhance or impair the insulin signaling pathway, have been found to regulate miRNA expression in both in vitro and in vivo studies. This review provides an overview of the current knowledge of how dietary components influence the expression of miRNAs related to the control of the insulin signaling pathway and discusses the potential application of these findings in precision nutrition.

Irisin alleviates the pyroptosis of β cells in T2DM by inhibiting NLRP3 inflammasome through regulating miR-19b-3p/SOCS3/STAT3 axis mediated autophagy

The purpose of this study was to analyze the mechanism by which irisin affects β-cell pyroptosis in type 2 diabetes mellitus (T2DM). The in vivo T2DM model was established by raised with high-fat diet and intraperitoneally injection of streptozocin. Min6 cells were divided into four groups: negative control (NC), high glucose (HG), HG + irisin, and HG + irisin+3-MA. The cell viability was determined by CCK-8 assay. Dual-luciferase gene reporter assay was conducted to confirm the binding between miR-19b-3p and SOCS3. The expression level of FNDC5 and GSDMD was visualized using the immunofluorescence assay. The protein level of FNDC5, Beclin1, LC3II/I, NLRP3, cleaved-caspase-1, GSDMD-N, STAT3, p-STAT3, and SOCS3 was determined by Western blotting. The secretion of irisin, lactate dehydrogenase (LDH), and insulin was checked by ELISA. In vivo results showed that pathological changes in islet tissues with declined number of β cells, elevated FBG value, decreased FIN and HOMA-β value, elevated autophagy-associated proteins expressions, and activated NLRP3 signaling in T2DM mice, which were dramatically reversed by FNDC5 overexpression. Furthermore, the declined level of miR-19b-3p and p-STAT3, as well as the upregulation of SOCS3, was greatly rescued by FNDC5 overexpression. The in vitro data confirmed the binding site between SOCS3 and miR-19b-3p. SOCS3 was downregulated and p-STAT3 was upregulated in miR-19b-3p mimic-treated Min6 cells. In HG-stimulated Min6 cells, the elevated cell viability, increased production of insulin, decreased release of LDH, and inactivated NLRP3 signaling induced by irisin were abolished by miR-19b-3p inhibitor and STAT3 inhibitor. The increased level of autophagy-related proteins and activated SOCS3/STAT3 axis induced by irisin in HG-stimulated Min6 cells were abolished by miR-19b-3p inhibitor. The inhibitory effect of irisin against NLRP3 signaling in HG-stimulated Min6 cells was abrogated by 3-MA. In conclusion, irisin alleviated the pyroptosis of β cells in T2DM by inhibiting NLRP3 signaling through miR-19b-3p/SOCS3/STAT3 axis mediated autophagy.

The role of ncRNA regulatory mechanisms in diseases-case on gestational diabetes

Non-coding RNAs (ncRNAs) are a class of RNA molecules that do not have the potential to encode proteins. Meanwhile, they can occupy a significant portion of the human genome and participate in gene expression regulation through various mechanisms. Gestational diabetes mellitus (GDM) is a pathologic condition of carbohydrate intolerance that begins or is first detected during pregnancy, making it one of the most common pregnancy complications. Although the exact pathogenesis of GDM remains unclear, several recent studies have shown that ncRNAs play a crucial regulatory role in GDM. Herein, we present a comprehensive review on the multiple mechanisms of ncRNAs in GDM along with their potential role as biomarkers. In addition, we investigate the contribution of deep learning-based models in discovering disease-specific ncRNA biomarkers and elucidate the underlying mechanisms of ncRNA. This might assist community-wide efforts to obtain insights into the regulatory mechanisms of ncRNAs in disease and guide a novel approach for early diagnosis and treatment of disease.

Oral probiotics increased the proportion of Treg, Tfr, and Breg cells to inhibit the inflammatory response and impede gestational diabetes mellitus

BACKGROUND

Children of mothers with gestational diabetes mellitus (GDM) are more prone to acquire type 2 diabetes and obesity as adults. Due to this link, early intervention strategies that alter the gut microbiome may benefit the mother and kid long-term. This work uses metagenomic and transcriptome sequencing to investigate how probiotics affect gut microbiota dysbiosis and inflammation in GDM.

METHODS

GDM and control metagenomic sequencing data were obtained from the SRA database. This metagenomic data helped us understand gut microbiota abundance and function. KEGG detected and extracted functional pathway genes. Transcriptome sequencing data evaluated GDM-related gene expression. Finally, GDM animal models were given probiotics orally to evaluate inflammatory response, regulatory immune cell fractions, and leptin protein levels.

RESULTS

GDM patients had more Fusobacteria and Firmicutes, while healthy people had more Bacteroidetes. Gut microbiota composition may affect GDM by altering the L-aspartate and L-asparagine super pathways. Mannan degradation and the super pathway of L-aspartate and L-asparagine synthesis enhanced in GDM mice with leptin protein overexpression. Oral probiotics prevent GDM by lowering leptin. Oral probiotics increased Treg, Tfr, and Breg cells, which decreased TNF-α and IL-6 and increased TGF-β and IL-10, preventing inflammation and preserving mouse pregnancy.

CONCLUSION

Dysbiosis of the gut microbiota may increase leptin expression and cause GDM. Oral probiotics enhance Treg, Tfr, and Breg cells, which limit the inflammatory response and assist mice in sustaining normal pregnancy. Thus, oral probiotics may prevent GDM, enabling targeted gut microbiota modulation and maternal and fetal health.

Effects of antidiabetics and exercise therapy on suppressors of cytokine signaling-1, suppressors of cytokine signaling-3, and insulin receptor substrate-1 molecules in diabetes and obesity

OBJECTIVE

Pathological destruction of insulin signaling molecules such as insulin receptor substrate, especially due to the increase in suppressors of cytokine signaling molecules, has been demonstrated in experimental diabetes. The contribution of suppressors of cytokine signaling proteins to the development of insulin resistance and the effects of antidiabetic drugs and exercise on suppressors of cytokine signaling proteins are not clearly known.

METHODS

A total of 48 Wistar albino adult male rats were divided into six groups: control group, obese group with diabetes, obese diabetic rats treated with metformin, obese diabetic rats treated with pioglitazone, obese diabetic rats treated with exenatide, and obese diabetic rats with applied exercise program. Immunohistochemical staining was performed in both the liver and adipose tissue.

RESULTS

There was a statistically significant decrease in suppressors of cytokine signaling-1, a decrease in suppressors of cytokine signaling-3, an increase in insulin receptor substrate-1, and a decrease in immunohistochemical staining in the obese group treated with metformin and exenatide compared to the obese group without treatment in the liver tissue (p<0.05). A statistically significant decrease in immunohistochemical staining of suppressors of cytokine signaling-1 and suppressors of cytokine signaling-3 was found in the obese group receiving exercise therapy compared to the obese group without treatment in visceral adipose tissue (p<0.05). Likewise, no significant immunohistochemistry staining was seen in diabetic obese groups.

CONCLUSION

Metformin or exenatide treatment could prevent the degradation of insulin receptor substrate-1 protein by reducing the effect of suppressors of cytokine signaling-1 and suppressors of cytokine signaling-3 proteins, especially in the liver tissue. In addition, exercise can play a role as a complementary therapy by reducing suppressors of cytokine signaling-1 and suppressors of cytokine signaling-3 proteins in visceral adipose tissue.

Gestational Diabetes Sensitizes Mice to Future Metabolic Syndrome That Can Be Relieved by Activating CAR

Diabetes and related metabolic syndrome are common metabolic disorders. Gestational diabetes mellitus (GDM) is rather prevalent in the clinic. Although most GDM resolves after therapeutic intervention and/or after delivery, the long-term health effect of GDM remains to be better understood. The constitutive androstane receptor (CAR), initially characterized as a xenobiotic receptor, was more recently proposed to be a therapeutic target for obesity and type 2 diabetes mellitus (T2DM). In this study, high-fat diet (HFD) feeding was used to induce GDM. Upon delivery, GDM mice were returned to chow diet until the metabolic parameters were normalized. Parous non-GDM control females or metabolically normalized GDM females were then subjected to HFD feeding to induce nongestational obesity and T2DM. Our results showed that GDM sensitized mice to metabolic abnormalities induced by a second hit of HFD. Treatment with the CAR agonist 1,4-bis [2-(3,5 dichloropyridyloxy)] benzene efficiently attenuated GDM-sensitized and HFD-induced obesity and T2DM, including decreased body weight, improved insulin sensitivity, inhibition of hyperglycemia and hepatic steatosis, increased oxygen consumption, and decreased adipocyte hypertrophy. In conclusion, our results have established GDM as a key risk factor for the future development of metabolic disease. We also propose that CAR is a therapeutic target for the management of metabolic disease sensitized by GDM.

Metformin improves high‑fat diet‑induced insulin resistance in mice by downregulating the expression of long noncoding RNA NONMMUT031874.2

Metformin (MET) is the first-line therapeutic option for patients with type 2 diabetes that has garnered substantial attention over recent years. However, an insufficient number of studies have been performed to assess its effects on insulin resistance and the expression profile of long noncoding RNAs (lncRNAs). The present study divided mice into three groups: Control group, high-fat diet (HFD) group and HFD + MET group. A high-throughput sequencing analysis was conducted to detect lncRNA and mRNA expression levels, and differentially expressed lncRNAs were selected. Subsequently, the differentially expressed lncRNAs were validated both in vivo and in vitro (mouse liver AML12 cells treated with Palmitic acid) models of insulin resistance. After validating randomly selected lncRNAs via reverse transcription-quantitative PCR a novel lncRNA, NONMMUT031874.2, was identified, which was upregulated in the HFD group and reversed with MET treatment. To investigate the downstream mechanism of NONMMUT031874.2, lncRNA-microRNA (miR/miRNA)-mRNA co-expression network was constructed and NONCODE, miRBase and TargetScan databases were used, which indicated that NONMMUT031874.2 may regulate suppressor of cytokine signaling 3 by miR-7054-5p. For the in vitro part of the present study, AML12 cells were transfected with small interfering RNA to knock down NONMMUT031874.2 expression before being treated with palmitic acid (PA) and MET. The results showed that the expression of NONMMUT031874.2 was significantly increased whereas miR-7054-5p expression was significantly decreased by PA treatment. By contrast, after knocking down NONMMUT031874.2 expression or treatment with MET, the aforementioned in vitro observations were reversed. In addition, it was also found that NONMMUT031874.2 knockdown and treatment with MET exerted similar effects in alleviating insulin resistance and whilst decreasing glucose concentration in AML12 cells. These results suggest that MET treatment can ameliorate insulin resistance by downregulating NONMMUT031874.2 expression.