Duodenal long noncoding RNAs are associated with glycemic control after bariatric surgery in high-fat diet-induced diabetic mice

Effectiveness of Roux-en-Y Gastric Bypass in Patients with Type 2 Diabetes: A Meta-analysis of Randomized Controlled Trials

This meta-analysis aimed to evaluate the effectiveness of Roux-en-Y gastric bypass (RYGB) in people living with type 2 diabetes mellitus (T2DM). A comprehensive search was conducted in the PubMed database up to January 2024. A random-effects model was used to calculate the pooled standard mean differences (SMDs) and odds ratios (ORs). Ten studies were included in our review. The RYGB group demonstrated significantly better outcomes compared to the non-surgical group in multiple measures. These included higher triple criteria compliance rates (OR 9.04, 95% CI 3.22-25.36), complete T2DM remission (OR 15.37, 95% CI 4.42-53.41), and partial T2DM remission (OR 11.49, 95% CI 3.57-37.03). Additionally, improvements were observed in glycated hemoglobin A1c (HbA1c) levels (SMD - 1.41, 95% CI - 2.22 to - 0.61), with HbA1c < 6.0% (OR 8.54, 95% CI 3.38-21.62) and HbA1c < 7.0% (OR 5.62, 95% CI 3.20-9.86). Fasting blood glucose (FBG) levels also showed improvement (SMD - 0.43, 95% CI - 0.71 to - 0.14), with a higher proportion achieving FBG < 100 mg/dl (OR 11.83, 95% CI 4.75-29.43). Other notable outcomes included significant percentage of total weight loss (%TWL: SMD 1.88, 95% CI 1.39-2.37), reductions in body mass index (BMI: SMD - 2.28, 95% CI - 3.52 to - 1.04), and improvements in lipid profiles, including low-density lipoprotein (LDL) levels (SMD - 1.01, 95% CI - 1.91 to - 0.11) and LDL < 2.59 mmol/L (OR 3.65, 95% CI 1.94-6.87). In addition, high-density lipoprotein (HDL) levels increased (SMD 1.30, 95% CI 0.55-2.05), while triglycerides (SMD - 1.11, 95% CI - 1.70 to - 0.52), systolic blood pressure (SBP: SMD - 0.38, 95% CI - 0.70 to - 0.06), and diastolic blood pressure (DBP: SMD - 0.41, 95% CI - 0.63 to - 0.18) decreased. A greater proportion of patients in the RYGB group achieved SBP < 130 mmHg (OR 3.15, 95% CI 1.61-6.13). Moreover, reductions were noted in insulin use (OR 0.25, 95% CI 0.14-0.46), diabetes medication use (SMD - 1.95, 95% CI - 3.32 to - 0.57), and peripheral neuropathy (OR 0.13, 95% CI 0.02-0.79). However, no significant differences were observed in hypertension medication use or retinopathy between the two groups. RYGB was found to be effective in improving glycemic control, promoting weight loss, enhancing lipid profiles, and managing blood pressure. It also significantly reduced the need for postoperative diabetes medications and the incidence of diabetic peripheral neuropathy in people living with T2DM.

Changes in Circulating Levels of Long Non-Coding RNA p5549 and p19461 Following Metabolic Bariatric Surgery (MBS): A Prospective Study

BACKGROUND

Obesity is attributed to a combination of factors such as lifestyle, environmental influences, and genetic background. Nowadays, the issue of obesity has grown to an epidemic scale. Environmental changes, having contributed to the sharp rise in obesity prevalence, are not the only contributing etiologic factors. Inherent biological variables interact with environmental factors resulting in obesity. Epigenetic mechanisms may explain part of obesity heritability. One of the recently discovered epigenetic mechanisms for controlling gene expression is long non-coding RNAs (lncRNAs). Circulating lncRNA p5549 and p19461 levels were reported to be significantly lower in individuals with obesity. This study aimed to evaluate whether weight loss following metabolic/bariatric surgery (MBS) can be related to altered expression levels of those lncRNAs, which have been reported to be reduced in individuals with obesity.

METHODS

Comparison of circulating levels of lncRNA p5549 and p19461 before and 12 weeks after MBS in thirty-four patients was conducted to evaluate whether MBS can revert the altered levels of these lncRNAs. None of the participating patients were lost to follow-up, and all underwent re-evaluation of post-surgical expression levels.

RESULTS

lncRNA p5549 expression levels in serum were found to increase significantly in the postoperative samples compared to preoperative samples (fold increase: 4.63 ± 7.68, p = 0.014).

CONCLUSION

Epigenetic changes in patients with obesity, specifically lncRNA-p5549 expression levels, are reversed after MBS. The postoperative increase in the expression levels of lncRNA- p19461 was not statistically significant.

Effect of bariatric surgery on metabolism in diabetes and obesity comorbidity: Insight from recent research

Obesity is a prevalent cause of diabetes mellitus (DM) and is a serious danger to human health. Type 2 DM (T2DM) mostly occurs along with obesity. Foodborne obesity-induced DM is caused by an excessive long-term diet and surplus energy. Bariatric surgery can improve the symptoms of T2DM in some obese patients. But different types of bariatric surgery may have different effects. There are some models built by researchers to discuss the surgical procedures' effects on metabolism in diabetes animal models and diabetes patients. It is high time to conclude all this effects and recommend procedures that can better improve metabolism.

Molecular mechanisms of noncoding RNA and epigenetic regulation in obesity with consequent diabetes mellitus development

Diabetes mellitus (DM) and obesity have become two of the most prevalent and challenging diseases worldwide, with increasing incidence and serious complications. Recent studies have shown that noncoding RNA (ncRNA) and epigenetic regulation play crucial roles in the pathogenesis of DM complicated by obesity. Identification of the involvement of ncRNA and epigenetic regulation in the pathogenesis of diabetes with obesity has opened new avenues of investigation. Targeting these mechanisms with small molecules or RNA-based therapies may provide a more precise and effective approach to diabetes treatment than traditional therapies. In this review, we discuss the molecular mechanisms of ncRNA and epigenetic regulation and their potential therapeutic targets, and the research prospects for DM complicated with obesity.

Duodenal-Jejunal bypass improves metabolism and re-models extra cellular matrix through modulating ceRNA network

BACKGROUND

Bariatric surgery (BS) is an effective approach in treating obesity and ameliorating T2DM with obesity. Our previous studies demonstrated that duodenal-jejunal bypass (DJB) altered long non-coding RNAs (lncRNAs) in the gastrointestinal system, which is associated with modulation of lipid metabolism, and glycemic control through entero-pancreatic axis and gut-brain axis. The adipose non-coding RNA expression profile and the underlying competing endogenous RNA (ceRNA) regulatory network pattern post DJB needs further research and investigation.

RESULTS

In this study, we compared the lncRNAs, circular RNAs (circRNAs) and messenger RNAs (mRNAs) expression in adipose tissues between the sham group and the DJB group. 2219 differentially expressed mRNAs (DEmRNAs), 722 differential expression of lncRNAs (DElncRNAs) and 425 differential expression of circRNAs (DEcircRNAs) were identified. GO terms and KEGG pathways analysis of the DEmRNAs implied that the dysregulated adipose mRNAs were associated with lipid, amino acid metabolism, insulin resistance, and extra cellular matrix (ECM)-related pathways. Moreover, via analyzing ceRNA regulatory networks of DElncRNAs and DEcircRNAs, 31 hub DE mRNAs, especially Mpp7, 9330159F19Rik, Trhde. Trdn, Sorbs2, were found on these pathways.

CONCLUSIONS

The role of DJB in adipose tends to remodel ECM and improve the energy metabolism through the ceRNA regulatory network.

Downregulation of hepatic lncRNA Gm19619 improves gluconeogenesis and lipogenesis following vertical sleeve gastrectomy in mice

Long non-coding RNAs (lncRNAs) are emerging important epigenetic regulators in metabolic processes. Whether they contribute to the metabolic effects of vertical sleeve gastrectomy (VSG), one of the most effective treatments for sustainable weight loss and metabolic improvement, is unknown. Herein, we identify a hepatic lncRNA Gm19619, which is strongly repressed by VSG but highly up-regulated by diet-induced obesity and overnight-fasting in mice. Forced transcription of Gm19619 in the mouse liver significantly promotes hepatic gluconeogenesis with the elevated expression of G6pc and Pck1. In contrast, AAV-CasRx mediated knockdown of Gm19619 in high-fat diet-fed mice significantly improves hepatic glucose and lipid metabolism. Mechanistically, Gm19619 is enriched along genomic regions encoding leptin receptor (Lepr) and transcription factor Foxo1, as revealed in chromatin isolation by RNA purification (ChIRP) assay and is confirmed to modulate their transcription in the mouse liver. In conclusion, Gm19619 may enhance gluconeogenesis and lipid accumulation in the liver.

The Association of lncRNA and mRNA Changes in Adipose Tissue with Improved Insulin Resistance in Type 2 Obese Diabetes Mellitus Rats after Roux-en-Y Gastric Bypass

Objective

Roux-en-Y gastric bypass (RYGB) has shown good effects in improving obesity and type II diabetes mellitus (T2DM), but the underlying mechanisms remain unclear. This study explored the changes of related lncRNAs, mRNAs, and signaling pathways in white adipose tissue of T2DM rats after RYGB based on RNA-Seq sequencing, with the aim to provide a theoretical basis for RYGB treatment.

Methods

T2DM rat models were established by continuous feeding with a high-fat diet and injection of streptozotocin (STZ), after which they underwent RYGB or sham surgery. After the surgery, their body weight was measured weekly. Their fasting blood glucose (FBG) and fasting serum insulin (FSI) were also measured. A homeostasis model assessment of insulin resistance (HOMA-IR) was calculated at weeks 0, 8, and 12. Besides, white adipose tissue of T2DM rats was collected for RNA-Seq sequencing and validated by qRT-PCR. A series of bioinformatics analyses, such as differential expression genes (DEGs) screening, was performed. GO and KEGG functional enrichment analysis and protein-protein interaction (PPI) network construction were conducted based on the sequencing data.

Results

RYGB surgery could significantly inhibit the weight growth rate and decrease the FBG, FSI, and HOMA-IR of T2DM rats. Bioinformatics analysis of RNA sequencing (RNA-Seq) results revealed that 87 DE- lncRNAs (49 upregulated and 38 downregulated) and 1,824 DEGs (896 upregulated and 928 downregulated) were present in between the RYGB group and Sham group. GO and KEGG analysis showed that the target genes of DEGs and differentially expressed lncRNAs (DE-lncRNAs) were mainly associated with amino acid metabolism, fatty acid metabolism, channel activity, and other processes. In addition, the PPI network diagram also displayed that genes such as Fasn, Grin3a, and Nog could be key genes playing a role after RYGB. qRT-PCR showed that the expression level of Grin3a in the RYGB group was significantly increased compared with the Sham group, while the expression of Fasn and Nog was significantly decreased, which was consistent with the sequencing results.

Conclusion

Using RNA-Seq sequencing, this study revealed the changes of related lncRNAs, mRNAs, and signaling pathways in the white adipose tissue of T2DM rats after RYGB and identified Fasn, Grin3a, and Nog as potential key genes to function after RYGB.

Alteration of Ileal lncRNAs After Duodenal–Jejunal Bypass Is Associated With Regulation of Lipid and Amino Acid Metabolism

Metabolic and bariatric surgery (MBS) can generate a drastic shift of coding and noncoding RNA expression patterns in the gastrointestinal system, which triggers organ function remodeling and may induce type 2 diabetes (T2D) remission. Our previous studies have demonstrated that the altered expression profiles of duodenal and jejunal long noncoding RNAs (lncRNAs) after the duodenal–jejunal bypass (DJB), an investigational procedure and research tool of MBS, can improve glycemic control by modulating the entero-pancreatic axis and gut–brain axis, respectively. As an indiscerptible part of the intestine, the ileal lncRNA expression signatures after DJB and the critical pathways associated with postoperative correction of the impaired metabolism need to be investigated too. High-fat diet-induced diabetic mice were randomly assigned into two groups receiving either DJB or sham surgery. Compared to the sham group, 1,425 dysregulated ileal lncRNAs and 552 co-expressed mRNAs were identified in the DJB group. Bioinformatics analysis of the differently expressed mRNAs and predicted target genes or transcriptional factors indicated that the dysregulated ileal lncRNAs were associated with lipid and amino acid metabolism-related pathways. Moreover, a series of lncRNAs and their potential target mRNAs, especially NONMMUT040618, Pxmp4, Pnpla3, and Car5a, were identified on the pathway. In conclusion, DJB can induce remarkable alteration of ileal lncRNA and mRNA expression. The role of the ileum in DJB tends to re-establish the energy homeostasis by regulating the lipid and amino acid metabolism.

An Overview of Epigenetics in Obesity: The Role of Lifestyle and Therapeutic Interventions

Obesity has become a global epidemic that has a negative impact on population health and the economy of nations. Genetic predispositions have been demonstrated to have a substantial role in the unbalanced energy metabolism seen in obesity. However, these genetic variations cannot entirely explain the massive growth in obesity over the last few decades. Accumulating evidence suggests that modern lifestyle characteristics such as the intake of energy-dense foods, adopting sedentary behavior, or exposure to environmental factors such as industrial endocrine disruptors all contribute to the rising obesity epidemic. Recent advances in the study of DNA and its alterations have considerably increased our understanding of the function of epigenetics in regulating energy metabolism and expenditure in obesity and metabolic diseases. These epigenetic modifications influence how DNA is transcribed without altering its sequence. They are dynamic, reflecting the interplay between the body and its surroundings. Notably, these epigenetic changes are reversible, making them appealing targets for therapeutic and corrective interventions. In this review, I discuss how these epigenetic modifications contribute to the disordered energy metabolism in obesity and to what degree lifestyle and weight reduction strategies and pharmacological drugs can restore energy balance by restoring normal epigenetic profiles.

Non-Coding RNAs: Novel Players in Insulin Resistance and Related Diseases

The rising prevalence of metabolic diseases related to insulin resistance (IR) have stressed the urgent need of accurate and applicable tools for early diagnosis and treatment. In the last decade, non-coding RNAs (ncRNAs) have gained growing interest because of their potential role in IR modulation. NcRNAs are variable-length transcripts which are not translated into proteins but are involved in gene expression regulation. Thanks to their stability and easy detection in biological fluids, ncRNAs have been investigated as promising diagnostic and therapeutic markers in metabolic diseases, such as type 2 diabetes mellitus (T2D), obesity and non-alcoholic fatty liver disease (NAFLD). Here we review the emerging role of ncRNAs in the development of IR and related diseases such as obesity, T2D and NAFLD, and summarize current evidence concerning their potential clinical application.

Intestinal extracellular vesicles are altered by vertical sleeve gastrectomy

Bariatric surgery is the most effective treatment for obesity and its comorbidities. However, our understanding of the molecular mechanisms behind its beneficial effects is limited. Extracellular vesicles (EVs) comprise an important mode of intercellular communication. They carry nucleic acids, hormones, and signaling molecules and regulate multiple processes. Our aim was to test the role of EVs in the effects of vertical sleeve gastrectomy (VSG) using a mouse model. Small intestinal EVs were obtained from the mice that underwent VSG or control surgery and were on chow or high-fat diet or diet-restricted, and then they were subjected to the proteomic analysis. Enteroid and bacterial cultures were treated with EVs to evaluate their survival effect. A mouse cohort received intraduodenal administration of EVs from VSG or Sham mice for 10 days. Body weight, glucose metabolism, and intestinal morphology were evaluated. EVs were enriched in the intestinal lumen and mucus of VSG compared with Sham mice. Protein composition of VSG and Sham-derived EVs was highly distinct. When introduced into culture, VSG EVs decreased survival of intestinal enteroids and, conversely, promoted proliferation of bacteria. Mice administered with EVs obtained from VSG and Sham groups did not show differences in body weight, food intake, or glucose metabolism. Intestinal morphology was altered, as VSG EVs caused reduction of ileal villi length and decreased epithelial proliferation in the jejunum and ileum. VSG causes remodeling of intestinal EVs, which results in unique protein composition. VSG-derived EVs exhibit cytotoxic effects on epithelial cells and reduce proliferation of intestinal progenitor cells in mice.NEW & NOTEWORTHY This is the first study that investigates the impact of bariatric surgery on protein composition of intestinal extracellular vesicles. Extracellular vesicle composition is greatly altered after vertical sleeve gastrectomy and may potentially modulate various signaling pathways. In our study, extracellular vesicles from vertical sleeve gastrectomy-treated mice promote bacterial proliferation but exhibit cytotoxic effect on epithelial cells and reduce proliferation of intestinal progenitor cells in mice.

Comprehensive analysis of long non-coding RNAs and mRNAs in skeletal muscle of diabetic Goto-Kakizaki rats during the early stage of type 2 diabetes

Skeletal muscle long non-coding RNAs (lncRNAs) were reported to be involved in the development of type 2 diabetes (T2D). However, little is known about the mechanism of skeletal muscle lncRNAs on hyperglycemia of diabetic Goto-Kakizaki (GK) rats at the age of 3 and 4 weeks. To elucidate this, we used RNA-sequencing to profile the skeletal muscle transcriptomes including lncRNAs and mRNAs, in diabetic GK and control Wistar rats at the age of 3 and 4 weeks. In total, there were 438 differentially expressed mRNAs (DEGs) and 401 differentially expressed lncRNAs (DELs) in skeletal muscle of 3-week-old GK rats compared with age-matched Wistar rats, and 1000 DEGs and 726 DELs between GK rats and Wistar rats at 4 weeks of age. The protein-protein interaction analysis of overlapping DEGs between 3 and 4 weeks, the correlation analysis of DELs and DEGs, as well as the prediction of target DEGs of DELs showed that these DEGs (Pdk4, Stc2, Il15, Fbxw7 and Ucp3) might play key roles in hyperglycemia, glucose intolerance, and increased fatty acid oxidation. Considering the corresponding co-expressed DELs with high correlation coefficients or targeted DELs of these DEGs, our study indicated that these dysregulated lncRNA-mRNA pairs (NONRATG017315.2-Pdk4, NONRATG003318.2-Stc2, NONRATG011882.2-Il15, NONRATG013497.2-Fbxw7, MSTRG.1662-Ucp3) might be related to above biological processes in GK rats at the age of 3 and 4 weeks. Our study could provide more comprehensive knowledge of mRNAs and lncRNAs in skeletal muscle of GK rats at 3 and 4 weeks of age. And our study may provide deeper understanding of the underlying mechanism in T2D of GK rats at the age of 3 and 4 weeks.

Obesity-Related Epigenetic Changes After Bariatric Surgery

Objective: In recent years, an increasing number of studies have begun focusing on epigenetics as a link between environmental factors and a greater predisposition to the development of obesity and its comorbidities. An important challenge in this field is the evaluation of the possibility of the reversal of obesity-related epigenetic marks by means of therapy to induce weight loss and if the beneficial effects of therapy in reducing obesity are mediated by epigenetic mechanisms. We aimed to offer an outline of the current results regarding to the impact of bariatric surgery on epigenetic regulation, as well as to show if the beneficial effect of this intervention could be mediated by epigenetic mechanisms. Methods: A review of the scientific publications in PubMed was performed by using key words related to obesity, epigenetics and bariatric surgery to provide an update of recent findings in this area of research. The most relevant and recently published articles and abstracts were selected to frame this review. Results: Previous studies have demonstrated the presence of differential DNA methylation after bariatric surgery and the differential expression of non-coding RNAs. Therefore, epigenetic regulation could mediate the benefit of bariatric surgery on body weight and the metabolic disturbances associated with excess body weight, such as insulin resistance, hypertension, and cardiovascular disease. This evidence is relatively new as epigenetic regulation was first evaluated in the obesity field only a few years ago. However, there is an urgent need to perform longitudinal studies to evaluate the capacity of epigenetic marks in the prediction of bariatric surgery response. Conclusions: Bariatric surgery appears to be capable of partially reversing the obesity-related epigenome. The identification of potential epigenetic biomarkers predictive for the success of bariatric surgery may open new doors to personalized therapy for severe obesity.