Bioinformatics analysis to obtain critical genes regulated in subcutaneous adipose tissue after bariatric surgery

CircMAPK9 promotes adipogenesis through modulating hsa-miR-1322/FTO axis in obesity

Circular RNA (circRNA) is a special category of non-coding RNA that has garnered increasing attention in the exploration of lipid metabolism. However, the functional regulation mechanisms of circRNAs in obesity diseases remain unclear. By whole transcriptome sequencing, a total of 164 circular RNAs were found to exhibit differential expression between lean and obese individuals. RT-qPCR was used to detect significant expression of circMAPK9 in obese individuals, and it was closely related to BMI. Western blot, triglyceride detection, and Oil Red O staining were employed to investigate the role of circMAPK9/hsa-miR-1322/FTO in adipogenesis. In adipocytes, the connection between hsa-miR-1322 and circMAPK9 was verified using fluorescence in situ hybridization, luciferase reporter assay, and RNA immunoprecipitation. It was found that circMAPK9 competed for binding hsa-miR-1322 in the cytoplasm, weakening the inhibitory effect on FTO and promoting adipogenesis. Our study revealed the regulatory mechanism and important role of circMAPK9 in the process of adipogenesis.

Large-scale renewable energy brings regionally disproportional air quality and health co-benefits in China

Developing renewable energy could jointly reduce air pollution, greenhouse gas emissions, and bring air pollution-related health co-benefits. However, the temporal and sub-national distributions of investment costs and human health co-benefits from renewable energy deployment remain unclear. To investigate this gap, we linked multiple models for a more comprehensive assessment of the economic-environmental-health co-benefits of renewable energy development in China. The results show that developing renewable energy can avoid 0.6 million premature mortalities, 151 million morbidities, and 111 million work-loss days in 2050. Meanwhile, the human health and economic co-benefits vary substantially across regions in China. Renewable energy can undoubtedly bring health and economic co-benefits. Nevertheless, the economic benefits lag considerably behind the high initial investment cost, first negative in 2030 (-0.6 trillion Yuan) and then positive in 2050 (2.9 trillion Yuan). Hence, renewable energy deployment strategy must be carefully designed considering the regional disparities.

Screening of Biomarkers in Liver Tissue after Bariatric Surgery Based on WGCNA and SVM-RFE Algorithms

As the most common chronic liver disease around the world, nonalcoholic fatty liver disease (NAFLD) has a close connection with obesity, diabetes, and metabolic syndrome. Bariatric surgery (BS) is considered to be the most effective treatment for NAFLD. However, the regulatory mechanism of hepatic lipid metabolism after BS remains poorly elucidated. By analyzing two transcriptome datasets regarding liver tissues after BS, namely, GSE83452 and GSE106737, we acquired 110 differentially expressed genes (DEGs). By further analysis of DEGs in terms of the weighted gene coexpression network analysis (WGCNA) and support vector machine-recursive feature elimination (SVM-RFE) algorithms, we identified four crucial genes participating in the regulation of hepatic lipid metabolism: SRGN, THEMIS2, SGK1, and FPR3. In addition, the results of gene set enrichment analysis (GSEA) showed that BS can activate immune-related regulatory pathways and change immune cell infiltration levels. Finally, through cellular level studies, we found that the silencing of SRGN affects the expression of SREBP-1, SIRT1, and FAS during adipogenesis in the liver and the formation of lipid droplets in the liver. In summary, the immune system in the liver is activated after BS, and SRGN participates in the regulation of hepatic lipid metabolism.

Relationships of ferroptosis-related genes with the pathogenesis in polycystic ovary syndrome

Background

Numerous studies have suggested that ferroptosis plays a significant role in the development of polycystic ovary syndrome (PCOS), but the mechanism remains unclear.

Methods

In this study, we explored the role of ferroptosis-related genes in the pathogenesis of PCOS using a comprehensive bioinformatics method. First, we downloaded several Gene Expression Omnibus (GEO) datasets and combined them into a meta-GEO dataset. Differential expression analysis was performed to screen for significant ferroptosis-related genes between the normal and PCOS samples. The least absolute shrinkage selection operator regression and support vector machine-recursive feature elimination were used to select the best signs to construct a PCOS diagnostic model. Receiver operating characteristic curve analysis and decision curve analysis were applied to test the performance of the model. Finally, a ceRNA network-related ferroptosis gene was constructed.

Results

Five genes, namely, NOX1, ACVR1B, PHF21A, FTL, and GALNT14, were identified from 10 differentially expressed ferroptosis-related genes to construct a PCOS diagnostic model. Finally, a ceRNA network including 117 lncRNAs, 67 miRNAs, and five ferroptosis-related genes was constructed.

Conclusion

Our study identified five ferroptosis-related genes that may be involved in the pathogenesis of PCOS, which may provide a novel perspective for the clinical diagnosis and treatment of PCOS.

Differential Gene Expression of Subcutaneous Adipose Tissue among Lean, Obese, and after RYGB (Different Timepoints): Systematic Review and Analysis

The main roles of adipose tissue include triglycerides storage and adipokine secretion, which regulate energy balance and inflammation status. In obesity, adipocyte dysfunction leads to proinflammatory cytokine production and insulin resistance. Bariatric surgery is the most effective treatment for obesity, the gold-standard technique being Roux-en-Y gastric bypass (RYGB). Since metabolic improvements after RYGB are clear, a better understanding of adipose tissue molecular modifications could be derived from this study. Thus, the aim of this systematic review was to find differentially expressed genes in subcutaneous adipose tissue of lean, obese and post-RYGB (distinct timepoints). To address this objective, publications from 2015-2022 reporting gene expression (candidate genes or transcriptomic approach) of subcutaneous adipose tissue from lean and obese individuals before and after RGYB were searched in PubMed, Elsevier, and Springer Link. Excluded publications were reviews, studies analyzing serum, other types of tissues, or bariatric procedures. A risk-of-bias summary was created for each paper using Robvis, to finally include 17 studies. Differentially expressed genes in post-RYGB vs. obese and lean vs. obese were obtained and the intersection among these groups was used for analysis and gene classification by metabolic pathway. Results showed that the lean state as well as the post-RYGB is similar in terms of increased expression of insulin-sensitizing molecules, inducing lipogenesis over lipolysis and downregulating leukocyte activation, cytokine production and other factors that promote inflammation. Thus, massive weight loss and metabolic improvements after RYGB are accompanied by gene expression modifications reverting the "adipocyte dysfunction" phenomenon observed in obesity conditions.