hsa-miR-607, lncRNA TUG1 and hsa_circ_0071106 can be combined as biomarkers in type 2 diabetes mellitus

Circ_0000284 Is Involved in Arsenite-Induced Hepatic Insulin Resistance Through Blocking the Plasma Membrane Translocation of GLUT4 in Hepatocytes via IGF2BP2/PPAR-γ

Arsenic exposure can induce liver insulin resistance (IR) and diabetes (DM), but the underlying mechanisms are not yet clear. Circular RNAs (circRNAs) are involved in the regulation of the onset of diabetes, especially in the progression of IR. This study aimed to investigate the role of circRNAs in arsenic-induced hepatic IR and its underlying mechanism. Male C57BL/6J mice were given drinking water containing sodium arsenite (0, 0.5, 5, or 50 ppm) for 12 months. The results show that sodium arsenite increased circ_0000284 expression, decreased insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) and peroxisome proliferator-activated receptor-γ (PPAR-γ), and inhibited cell membrane protein levels of insulin-responsive glucose transporter protein 4 (GLUT4) in the mouse livers, indicating that arsenic exposure causes liver damage and disruptions to glucose metabolism. Furthermore, sodium arsenite reduced glucose consumption and glycogen levels, increased the expression of circ_0000284, reduced the protein levels of IGF2BP2 and PPAR-γ, and inhibited GLUT4 protein levels in the cell membranes of insulin-treated HepG2 cells. However, a circ_0000284 inhibitor reversed arsenic exposure-induced reductions in IGF2BP2, PPAR-γ, and GLUT4 levels in the plasma membrane. These results indicate that circ_0000284 is involved in arsenite-induced hepatic insulin resistance through blocking the plasma membrane translocation of GLUT4 in hepatocytes via IGF2BP2/PPAR-γ. This study provides a scientific basis for finding early biomarkers for the control of arsenic exposure and type 2 diabetes mellitus (T2DM), and discovering new prevention and control measures.

Construction of circRNA-miRNA-mRNA ceRNA regulatory network and screening of diagnostic targets for tuberculosis

Tuberculosis (TB) is a chronic infectious disease caused by Mycobacterium tuberculosis (Mtb), which threatens human health and safety all over the world. Hundreds of thousands of people die from TB every year. Timely early diagnosis and treatment of patients is the most important measure to control the source of infection and curb the epidemic of tuberculosis. The existing diagnostic methods have the disadvantages of poor sensitivity and long culture time. Competitive endogenous RNAs (ceRNAs) can regulate the expression of corresponding target genes by competing for the same microRNA (miRNA) response elements (MREs) as mRNA. Recent studies have found that circRNA has the advantages of long half-life, good stability and tissue specificity, and can be used as a biomarker for predicting, diagnosing and treating various diseases, and is an ideal candidate for biomarkers in body fluid biopsy. In this study, transcriptome sequencing was performed on whole blood samples to screen out TB-related mirna and mRNA differential expression, and to construct the ceRNA regulatory network. Through the analysis of ceRNA regulatory network, it was found that circRNA could competitively bind has-miR-607 and induce down-regulation of has-miR-607, thereby inhibiting the expression of IFNG. The hsa_circ_0000566, hsa_circ_0001844, hsa_circ_0005408, hsa_circ_0007587, hsa_circ_0086710, IFNG and has-miR-607 couble be used as new diagnostic targets for TB. The results of this study not only provide a new perspective for studying the potential role of ceRNA regulatory network in tuberculosis, but also provide a new target and method for the diagnosis of tuberculosis.

A Comprehensive Bioinformatic Analysis Identifies a Tumor Suppressor Landscape of the MEG3 lncRNA in Breast Cancer

Breast cancer (BC) is the leading cause of cancer mortality in women and a major risk to world health. Therefore, effective strategies are required for prompt diagnosis and treatment. Nowadays, non-coding RNAs (ncRNAs), particularly long ncRNAs (lncRNAs), have assumed a significant role in the prognosis and diagnosis of diseases, including cancer. In the present study, surveying the bioinformatic tools, including the lncRNADisease v2.0, OncoDB, InteractiVenn, GEPIA, RAID, COXPRESdb, DAVID v6.8, GEO2R, and LncSEA, we proposed the Maternally Expressed Gene (MEG3) as a potential biomarker in BC. This lncRNA significantly downregulates in BC and is associated with tumor size, metastasis, and pathological stage. MEG3 expression is downregulated in several types of primary human cancers and tumor cell lines, which raises the possibility that it could act as a tumor suppressor. The results suggest that MEG3 may play a crucial role in fundamental pathways, including apoptosis, and interact with essential genes and proteins such as P53. It may also be associated with the prognosis, proliferation, migration, invasion, and metastasis of BC.

Biofluid-Derived Exosomal LncRNAs: Their Potential in Obesity and Related Comorbidities

Obesity has escalated into a critical global health crisis, tripling in prevalence since the mid-1970s. This increase mirrors the rise in metabolic-associated diseases such as type 2 diabetes (T2D) and its complications, certain cancers, and cardiovascular conditions. While substantial research efforts have enriched our understanding and led to the development of innovative management strategies for these diseases, the suboptimal response rates of existing therapies remain a major obstacle to effectively managing obesity and its associated conditions. Over the years, inter-organ communication (IOC) has emerged as a crucial factor in the development and progression of metabolic disorders. Exosomes, which are nano-sized vesicular couriers released by cells, play a significant role in this communication by transporting proteins, lipids, and nucleic acids across cellular landscapes. The available evidence indicates that exosomal RNAs present in biofluids such as blood, urine, milk, vitreous humor (VH), and cerebrospinal fluid (CSF) are altered in numerous diseases, suggesting their diagnostic and therapeutic potential. Long non-coding RNAs contained in exosomes (exo-lncRNAs) have attracted considerable interest, owing to their ability to interact with critical components involved in a multitude of metabolic pathways. Recent studies have found that alterations in exo-lncRNAs in biofluids correlate with several metabolic parameters in patients with metabolic-associated conditions; however, their exact roles remain largely unclear. This review highlights the diagnostic and therapeutic potential of exosomal lncRNAs in obesity and its associated conditions, emphasizing their role in IOC and disease progression, aiming to pave the way for further research in this promising domain.

Relationship of lncRNA FTX and miR-186-5p levels with diabetic peripheral neuropathy in type 2 diabetes and its bioinformatics analysis

BACKGROUND

Diabetic peripheral neuropathy (DPN) frequently occurs as a secondary condition in individuals with type 2 diabetes mellitus (T2DM).

OBJECTIVE

To explore the relationship of lncRNA FTX and miR-186-5p levels with DPN in T2DM.

METHODS

The study enrolled 50 patients with T2DM and 45 patients with DPN. Expression levels of FTX and miR-186-5p were measured by RT-qPCR. The levels of MDA, GSH, and SOD in the serum were measured to assess the patients' oxidative stress levels. In addition, the target genes of miR-186-5p were analyzed by bioinformatics.

RESULTS

Serum FTX levels were increased and miR-186-5p levels were decreased in patients with T2DM and DPN. Both of them had high diagnostic value for T2DM and DPN. In addition, FTX and miR-186-5p were risk factors for the onset of DPN in people with T2DM and were significantly correlated with oxidative stress indicators in patients.

CONCLUSION

FTX and miR-186-5p are closely related to the disease progression of DPN in people with T2DM and may become therapeutic targets for DPN in people with T2DM.

Diabetes and diabetic associative diseases: An overview of epigenetic regulations of TUG1

The epigenetic regulation of lncRNA TUG1 has garnered significant attention in the context of diabetes and its associated disorders. TUG1's multifaceted roles in gene expression modulation, and cellular differentiation, and it plays a major role in the growth of diabetes and the issues that are related to it due to pathological processes. In diabetes, aberrant epigenetic modifications can lead to dysregulation of TUG1 expression, contributing to disrupted insulin signaling, impaired glucose metabolism, and beta-cell dysfunction. Moreover, it has been reported that TUG1 contributes to the development of problems linked to diabetes, such as nephropathy, retinopathy, and cardiovascular complications, through epigenetically mediated mechanisms. Understanding the epigenetic regulations of TUG1 offers novel insights into the primary molecular mechanisms of diabetes and provides a possible path for healing interventions. Targeting epigenetic modifications associated with TUG1 holds promise for restoring proper gene expression patterns, ameliorating insulin sensitivity, and mitigating the inception and development of diabetic associative diseases. This review highlights the intricate epigenetic landscape that governs TUG1 expression in diabetes, encompassing DNA methylation and alterations in histone structure, as well as microRNA interactions.

Whole transcriptome sequencing analyses of islets reveal ncRNA regulatory networks underlying impaired insulin secretion and increased β-cell mass in high fat diet-induced diabetes mellitus

AIM

Our study aims to identify novel non-coding RNA-mRNA regulatory networks associated with β-cell dysfunction and compensatory responses in obesity-related diabetes.

METHODS

Glucose metabolism, islet architecture and secretion, and insulin sensitivity were characterized in C57BL/6J mice fed on a 60% high-fat diet (HFD) or control for 24 weeks. Islets were isolated for whole transcriptome sequencing to identify differentially expressed (DE) mRNAs, miRNAs, IncRNAs, and circRNAs. Regulatory networks involving miRNA-mRNA, lncRNA-mRNA, and lncRNA-miRNA-mRNA were constructed and functions were assessed through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses.

RESULTS

Despite compensatory hyperinsulinemia and a significant increase in β-cell mass with a slow rate of proliferation, HFD mice exhibited impaired glucose tolerance. In isolated islets, insulin secretion in response to glucose and palmitic acid deteriorated after 24 weeks of HFD. Whole transcriptomic sequencing identified a total of 1324 DE mRNAs, 14 DE miRNAs, 179 DE lncRNAs, and 680 DE circRNAs. Our transcriptomic dataset unveiled several core regulatory axes involved in the impaired insulin secretion in HFD mice, such as miR-6948-5p/Cacna1c, miR-6964-3p/Cacna1b, miR-3572-5p/Hk2, miR-3572-5p/Cckar and miR-677-5p/Camk2d. Additionally, proliferative and apoptotic targets, including miR-216a-3p/FKBP5, miR-670-3p/Foxo3, miR-677-5p/RIPK1, miR-802-3p/Smad2 and ENSMUST00000176781/Caspase9 possibly contribute to the increased β-cell mass in HFD islets. Furthermore, competing endogenous RNAs (ceRNA) regulatory network involving 7 DE miRNAs, 15 DE lncRNAs and 38 DE mRNAs might also participate in the development of HFD-induced diabetes.

CONCLUSIONS

The comprehensive whole transcriptomic sequencing revealed novel non-coding RNA-mRNA regulatory networks associated with impaired insulin secretion and increased β-cell mass in obesity-related diabetes.

Long noncoding RNAs as potential diagnostic biomarkers for diabetes mellitus and complications: A systematic review and meta-analysis

AIMS

Long noncoding RNAs (lncRNAs) may be associated with the development of type 2 diabetes mellitus and its complications; however, the findings remain controversial. We aimed to synthesize the available data to assess the diagnostic utility of lncRNAs for identification of type 2 diabetes mellitus and its consequences.

MATERIALS AND METHODS

We performed a systematic review and meta-analysis, searching PubMed, Embase, and Web of Science for articles published from September 11, 2015 to December 27, 2022. We evaluated human case-control or cohort studies on differential lncRNA expression in type 2 diabetes mellitus or its associated comorbidities. We excluded studies if they were non-peer reviewed or published in languages other than English. From 2387 identified studies, we included 17 (4685 participants).

RESULTS

Analysis of the pooled data showed that lncRNAs had a diagnostic area under the curve (AUC) of 0.84 (95% CI: 0.80-0.87), with a sensitivity of 0.79 (95% CI: 0.74-0.83) and a specificity of 0.75 (95% CI: 0.69-0.80). LncRNAs had an AUC of 0.65 for the diagnosis of prediabetes, with 82% sensitivity and 65% specificity.

CONCLUSIONS

LncRNAs may be promising diagnostic markers for type 2 diabetes mellitus and its complications.

Decrypting the circular RNAs does a favor for us: Understanding, diagnosing and treating diabetes mellitus and its complications

Circular RNAs (circRNAs), a novel type of single-stranded noncoding RNAs with a covalently closed loop structure, are generated in a circular conformation via non-canonical splicing or back-splicing events. Functionally, circRNAs have been elucidated to soak up microRNAs (miRNAs) and RNA binding proteins (RBPs), serve as protein scaffolds, maintain mRNA stability, and regulate gene transcription and translation. Notably, circRNAs are strongly implicated in the regulation of β-cell functions, insulin resistance, adipocyte functions, inflammation as well as oxidative stress via acting as miRNA sponges and RBP sponges. Basic and clinical studies have demonstrated that aberrant alterations of circRNAs expressions are strongly associated with the initiation and progression of diabetes mellitus (DM) and its complications. Here in this review, we present a summary of the biogenesis, transportation, degradation and functions of circRNAs, and highlight the recent findings on circRNAs and their action mechanisms in DM and its complications. Overall, this review should contribute greatly to our understanding of circRNAs in DM pathogenesis, offering insights into the further perspectives of circRNAs for DM diagnosis and therapy.

LncRNA LINC01018 Screens Type 2 Diabetes Mellitus and Regulates β Cell Function Through Modulating miR-499a-5p

Type 2 diabetes mellitus (T2DM) is characterized by hyperglycemia, which seriously endangers human health. The dysregulation of lncRNA LINC01018 in T2DM has been noticed in previous studies, but whether it served as a biomarker lacks validation. This study aimed to confirm the abnormal expression of LINC01018 in T2DM and reveals its specific function in regulating pancreatic β cell function. This study enrolled 77 T2DM patients and 41 healthy individuals and compared the plasma LINC01018 levels between two groups using PCR. The pancreatic β cell was induced with 25 mM glucose to mimic cell injury during T2DM. The effects of LINC01018 on β cell proliferation, dedifferentiation, and insulin production were evaluated by CCK8, western blotting, and ELISA. Moreover, the involvement of miR-499a-5p was also evaluated with luciferase reporter assay. Increased plasma LINC01018 was observed in T2DM patients compared with healthy individuals, which discriminates patients with high sensitivity and specificity. Upregulated LINC01018 was associated with patients' fasting blood glucose and weight loss. High glucose induced the increasing LINC01018 in pancreatic islet β cells and suppressed cell proliferation, insulin secretion, and promoted cell dedifferentiation. Silencing LINC01018 could alleviate the impaired function of β cells by high glucose, which was reversed by the knockdown by miR-499a-5p. Upregulated LINC01018 served as a potential diagnostic biomarker for T2DM and alleviated high glucose-induced β cell dysfunction via negatively modulating miR-499a-5p.

ETS2 promotes cardiomyocyte apoptosis and autophagy in heart failure by regulating lncRNA TUG1/miR-129-5p/ATG7 axis

Heart failure (HF) is a chronic disease in which the heart is unable to provide enough blood and oxygen to the peripheral tissues. Cardiomyocyte apoptosis and autophagy have been linked to HF progression. However, the underlying mechanism of HF is unknown. In this study, H₂ O₂ -treated AC16 cells were used as a cell model of HF. The mRNA and protein levels of related genes were examined using RT-qPCR and western blot. Cell viability and apoptosis were assessed using CCK-8 and flow cytometry, respectively. The interactions between ETS2, TUG1, miR-129-5p, and ATG7 were validated by luciferase activity, ChIP, and RNA-Binding protein Immunoprecipitation assays. According to our findings, H₂ O₂ stimulation increased the expression of ETS2, TUG1, and ATG7 while decreasing the expression of miR-129-5p in AC16 cells. Furthermore, H₂ O₂ stimulation induced cardiomyocyte apoptosis and autophagy, which were reversed by ETS2 depletion, TUG1 silencing, or miR-129-5p upregulation. Mechanistically, ETS2 promoted TUG1 expression by binding to the TUG1 promoter, and TUG1 sponged miR-129-5p to increase ATG7 expression. Furthermore, TUG1 overexpression reversed ETS2 knockdown-mediated inhibition of cardiomyocyte apoptosis and autophagy and miR-129-5p inhibition abolished TUG1 depletion-mediated suppression of cardiomyocyte apoptosis and autophagy in H₂ O₂ -induced AC16 cells. As presumed, ATG7 overexpression reversed miR-129-5p mimics-mediated repression of cardiomyocyte apoptosis and autophagy in H₂ O₂ -induced AC16 cells. Finally, ETS2 silencing reduced cardiomyocyte apoptosis and autophagy to slow HF progression by targeting the ETS2/TUG1/miR-129-5p/ATG7 axis, which may provide new therapeutic targets for HF treatment.

Long non-coding RNAs TUG1 and MEG3 in patients with type 2 diabetes and their association with endoplasmic reticulum stress markers

BACKGROUND

Long non-coding RNAs (lncRNAs), including taurine upregulated gene 1 (TUG1), metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), and maternally expressed 3 (MEG3) play a regulatory role in endoplasmic reticulum (ER) stress. The present study aimed to investigate the expression of these lncRNAs in patients with type 2 diabetes and their association with biochemical and ER stress parameters.

MATERIALS AND METHODS

Participants included 57 patients with diabetes and 32 healthy individuals. Real-time PCR was performed to assess MALAT1, TUG1, MEG3, ATF4, and CHOP gene expression in peripheral blood mononuclear cells. Plasma GRP78, advanced glycation end products (AGEs), and insulin were measured using enzyme-linked immunosorbent assay (ELISA), and insulin resistance (IR) was calculated by the homeostasis model assessment of insulin resistance (HOMA-IR).

RESULTS

The expression of TUG1, MEG3, ATF4, and CHOP genes was significantly increased in the patients with diabetes compared to healthy individuals. MALAT1 gene expression was also higher in patients group; although it did not reach significant levels. TUG1 and MEG3 expression revealed significant positive correlations with the indices of glycemic control, including FBS, HbA1c, HOMA-IR, and AGEs, as well as markers of ER stress. MALAT1 expression was also positively correlated with ATF4 and AGEs.

CONCLUSION

The expression levels of TUG1 and MEG3 lncRNAs were increased in patients with diabetes and were associated with glycemic control and components of ER stress. Thus, these lncRNAs might be considered appropriate markers to identify ER stress due to hyperglycemia.