Roles of long noncoding RNAs and small extracellular vesicle-long noncoding RNAs in type 2 diabetes

Polyethylene glycol loxenatide modulates lipid metabolism and insulin resistance through lncRNA steroid receptor RNA activator/cellular nucleic acid binding protein/Rho-associated coiled-coil kinase 2 axis in type 2 diabetes mellitus

BACKGROUND

Polyethylene glycol loxenatide (PEG-Loxe) is applied in treating type 2 diabetes mellitus. Nevertheless, the effect and mechanism of PEG-Loxe on lipid metabolism disorder and insulin resistance in type 2 diabetes mellitus are not fully understood.

METHODS

Type 2 diabetes mellitus rats developed by high-fat diet/streptozotocin injection were treated with PEG-Loxe (0.3 or 1 mg/kg). Insulin resistance was evaluated by fasting blood glucose (FBG), oral glucose tolerance test, fasting insulin, homeostasis model of assessment for insulin resistance and for insulin sensitivity. Immunohistochemistry, hematoxylin and eosin staining, and biochemistry measurements were performed to assess lipid metabolism. Inflammatory response and oxidative stress were assessed by inflammatory cytokines and reactive oxygen species. Genes' expressions were tested using RT-qPCR, western blot, and in situ hybridization. Relationships of molecules were validated by pull-down assay and RNA immunoprecipitation. mRNA stability was examined by actinomycin D assay.

RESULTS

High-PEG-Loxe decreased FBG and ameliorated glucose tolerance, hyperinsulinemia, and insulin resistance. Low-PEG-Loxe partly while high-PEG-Loxe apparently relieved hepatocyte injury, reduced lipase I, triglyceride, total cholesterol and leptin, and increased adiponectin in type 2 diabetes mellitus rats. PEG-Loxe mitigated inflammatory response and oxidative stress. High-PEG-Loxe reduced RhoA and Rho-associated coiled-coil kinase 2 (ROCK2) in liver tissues of type 2 diabetes mellitus rats, while both doses of PEG-Loxe decreased steroid receptor RNA activator (SRA). SRA overexpression reversed the protective functions of high-PEG-Loxe. SRA cooperated with cellular nucleic acid binding protein (CNBP) to enhance ROCK2 mRNA stability.

CONCLUSION

High-PEG-Loxe relieves insulin resistance and lipid metabolism disorder in type 2 diabetes mellitus through SRA/CNBP/ROCK2 axis. This research provides a molecular mechanism of PEG-Loxe for treating type 2 diabetes mellitus.

LncRNA LYPLAL1, miR-204-5p, and SIRT1: novel signatures for risk assessment of diabetic macrovascular complications

Long-term, uncontrolled diabetes mellitus can lead to micro- and macrovascular problems. The protective function of lncRNA LYPLAL1 is to reduce endothelium cell inflammation by upregulating sirtuin 1 (SIRT1) and reducing microRNA (miR)-204-5p. This work attempted to examine the lncRNA LYPLAL1/miR-204-5p/SIRT1 molecules as diagnostic biomarkers for diabetic MVC and to assess their clinical correlations. The study enrolled 32 controls, 32 patients with diabetes alone, and 32 patients with diabetic MVC. RT-qPCR, or quantitative real-time PCR, was utilized to determine the expression levels of lncRNA and miR. SIRT1 was measured by ELISA. When comparing cases with MVC to those without MVC, the lncRNA LYPLAL1 and SIRT1 values were significantly lower. Conversely, patients with MVC had significantly higher miR-204-5p levels than those without MVC. The LncRNA LYPLAL1 performed best in terms of detecting MVC. It attained 90.6% specificity and 96.9% sensitivity. A combination of three markers (lncRNA LYPLAL1, miR-204-5p, and SIRT1) yielded the best accuracy at 98.4%. LYPLAL1 expression appeared to be an independent MVC predictor. Adjusted OR for LYPLAL1 expression was 405 (95% CI: 1.4-1200) (p = 0.039). When we compared cases with MVC to those without MVC, the lncRNA LYPLAL1 and SIRT1 values were significantly lower. Patients with MVC had significantly higher miR-204-5p levels than those without MVC. LYPLAL1 LncRNA demonstrated the best performance characteristics. LncRNA LYPLAL1 expression is an independent predictor of MVC.

The Mechanism of Pyroptosis and Its Application Prospect in Diabetic Wound Healing

Pyroptosis defines a form of pro-inflammatory-dependent programmed cell death triggered by gasdermin proteins, which creates cytoplasmic pores and promotes the activation and accumulation of immune cells by releasing several pro-inflammatory mediators and immunogenic substances upon cell rupture. Pyroptosis comprises canonical (mediated by Caspase-1) and non-canonical (mediated by Caspase-4/5/11) molecular signaling pathways. Numerous studies have explored the contributory roles of inflammasome and pyroptosis in the progression of multiple pathological conditions such as tumors, nerve injury, inflammatory diseases and metabolic disorders. Accumulating evidence indicates that the activation of the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome results in the activation of pyroptosis and inflammation. Current evidence suggests that pyroptosis-dependent cell death plays a progressive role in the development of diabetic complications including diabetic wound healing (DWH) and diabetic foot ulcers (DFUs). This review presents a brief overview of the molecular mechanisms underlying pyroptosis and addresses the current research on pyroptosis-dependent signaling pathways in the context of DWH. In this review, we also present some prospective therapeutic compounds/agents that can target pyroptotic signaling pathways, which may serve as new strategies for the effective treatment and management of diabetic wounds.

Distinctive genes and signaling pathways associated with type 2 diabetes-related periodontitis: Preliminary study

The biological mechanisms underlying the pathogenesis of type 2 diabetes (T2DM)-related periodontitis remain unclear. This cross-sectional study evaluated the distinctive transcriptomic changes between tissues with periodontal health and with periodontitis in patients with T2DM. In this cross-sectional study, whole transcriptome sequencing was performed on gingival biopsies from non-periodontitis and periodontitis tissues from non-diabetic and diabetic patients. A differentially expressed gene (DEG) analysis and Ingenuity Pathway Analysis (IPA) assessed the genes and signaling pathways associated with T2DM-related periodontitis. Immunohistochemistry was performed to validate selected DEGs possibly involved in T2DM-related periodontitis. Four hundred and twenty and one thousand five hundred and sixty-three DEGs (fold change ≥ 2) were uniquely identified in the diseased tissues of non-diabetic and diabetic patients, respectively. The IPA predicted the activation of Phagosome Formation, Cardiac β-adrenergic, tRNA Splicing, and PI3K/AKT pathways. The IPA also predicted the inhibition of Cholesterol Biosynthesis, Adrenomedullin, and Inositol Phosphate Compounds pathways in T2DM-related periodontitis. Validation of DEGs confirmed changes in protein expression of PTPN2, PTPN13, DHCR24, PIK3R2, CALCRL, IL1RN, IL-6R and ITGA4 in diseased tissues in diabetic subjects. Thus, these preliminary findings indicate that there are specific genes and functional pathways that may be involved in the pathogenesis of T2DM-related periodontitis.

Small extracellular vesicles - A host for advanced bioengineering and "Trojan Horse" of non-coding RNAs

Small extracellular vesicles (sEVs) are a type of membranous vesicles that can be released by cells into the extracellular space. The relationship between sEVs and non-coding RNAs (ncRNAs) is highly intricate and interdependent. This symbiotic relationship plays a pivotal role in facilitating intercellular communication and holds profound implications for a myriad of biological processes. The concept of sEVs and their ncRNA cargo as a "Trojan Horse" highlights their remarkable capacity to traverse biological barriers and surreptitiously deliver their cargo to target cells, evading detection by the host-immune system. Accumulating evidence suggests that sEVs may be harnessed as carriers to ferry therapeutic ncRNAs capable of selectively silencing disease-driving genes, particularly in conditions such as cancer. This approach presents several advantages over conventional drug delivery methods, opening up new possibilities for targeted therapy and improved treatment outcomes. However, the utilization of sEVs and ncRNAs as therapeutic agents raises valid concerns regarding the possibility of unforeseen consequences and unintended impacts that may emerge from their application. It is important to consider the fundamental attributes of sEVs and ncRNAs, including by an in-depth analysis of the practical and clinical potentials of exosomes, serving as a representative model for sEVs encapsulating ncRNAs.

Non-coding RNA-mediated modulation of ferroptosis in cardiovascular diseases

Cardiovascular disease (CVD) is a major contributor to increasing morbidity and mortality worldwide and seriously threatens human health and life. Cardiomyocyte death is considered the pathological basis of various CVDs, including myocardial infarction, heart failure, and aortic dissection. Multiple mechanisms, such as ferroptosis, necrosis, and apoptosis, contribute to cardiomyocyte death. Among them, ferroptosis is an iron-dependent form of programmed cell death that plays a vital role in various physiological and pathological processes, from development and aging to immunity and CVD. The dysregulation of ferroptosis has been shown to be closely associated with CVD progression, yet its underlying mechanisms are still not fully understood. In recent years, a growing amount of evidence suggests that non-coding RNAs (ncRNAs), particularly microRNAs, long non-coding RNAs, and circular RNAs, are involved in the regulation of ferroptosis, thus affecting CVD progression. Some ncRNAs also exhibit potential value as biomarker and/or therapeutic target for patients with CVD. In this review, we systematically summarize recent findings on the underlying mechanisms of ncRNAs involved in ferroptosis regulation and their role in CVD progression. We also focus on their clinical applications as diagnostic and prognostic biomarkers as well as therapeutic targets in CVD treatment. DATA AVAILABILITY: No new data were created or analyzed in this study. Data sharing is not applicable to this article.

Exosomes in brain diseases: Pathogenesis and therapeutic targets

Exosomes are extracellular vesicles with diameters of about 100 nm that are naturally secreted by cells into body fluids. They are derived from endosomes and are wrapped in lipid membranes. Exosomes are involved in intracellular metabolism and intercellular communication. They contain nucleic acids, proteins, lipids, and metabolites from the cell microenvironment and cytoplasm. The contents of exosomes can reflect their cells' origin and allow the observation of tissue changes and cell states under disease conditions. Naturally derived exosomes have specific biomolecules that act as the "fingerprint" of the parent cells, and the contents changed under pathological conditions can be used as biomarkers for disease diagnosis. Exosomes have low immunogenicity, are small in size, and can cross the blood-brain barrier. These characteristics make exosomes unique as engineering carriers. They can incorporate therapeutic drugs and achieve targeted drug delivery. Exosomes as carriers for targeted disease therapy are still in their infancy, but exosome engineering provides a new perspective for cell-free disease therapy. This review discussed exosomes and their relationship with the occurrence and treatment of some neuropsychiatric diseases. In addition, future applications of exosomes in the diagnosis and treatment of neuropsychiatric disorders were evaluated in this review.

Non-coding RNAs regulating mitochondrial function in cardiovascular diseases

Cardiovascular disease (CVD) is the leading cause of disease-related death worldwide and a significant obstacle to improving patients' health and lives. Mitochondria are core organelles for the maintenance of myocardial tissue homeostasis, and their impairment and dysfunction are considered major contributors to the pathogenesis of various CVDs, such as hypertension, myocardial infarction, and heart failure. However, the exact roles of mitochondrial dysfunction involved in CVD pathogenesis remain not fully understood. Non-coding RNAs (ncRNAs), particularly microRNAs, long non-coding RNAs, and circular RNAs, have been shown to be crucial regulators in the initiation and development of CVDs. They can participate in CVD progression by impacting mitochondria and regulating mitochondrial function-related genes and signaling pathways. Some ncRNAs also exhibit great potential as diagnostic and/or prognostic biomarkers as well as therapeutic targets for CVD patients. In this review, we mainly focus on the underlying mechanisms of ncRNAs involved in the regulation of mitochondrial functions and their role in CVD progression. We also highlight their clinical implications as biomarkers for diagnosis and prognosis in CVD treatment. The information reviewed herein could be extremely beneficial to the development of ncRNA-based therapeutic strategies for CVD patients.