LncRNA as a regulator in the development of diabetic complications

Peptides based on the interface of hnRNPA2B1-transthyretin complex repress retinal angiogenesis in diabetic retinopathy

BACKGROUND

Heterogeneous nuclear ribonucleoprotein A2B1 (hnRNPA2B1) plays a vital role in angiogenesis, when its nucleic acid-binding domain is occupied by transthyretin (TTR), the neovascularization of human retinal microvascular endothelial cells (hRECs) is repressed under hyperglycemic conditions.

METHODS

HnRNPA2B1-targeting peptides (THIPs) were designed based on the core fragments at the TTR-hnRNPA2B1 interface. Biacore, Langmuir equilibrium adsorption, and co-immunoprecipitation (co-IP) assays were performed to determine the association between the THIPs and hnRNPA2B1. Proliferation and DNA synthesis in hRECs were detected using CCK-8 and EdU assays. Transwell, wound healing, and tube formation assays were used to evaluate migratory and the angiogenic capacity of hRECs. Related RNA and protein expression levels were tested by quantitative PCR and western blot assays, respectively. Streptozotocin (STZ)-induced diabetic retinopathy (DR) model rats were intravitreally injected with 5 μL of AAV9 virus (1 × 1012 vg/mL) every 8 weeks, with sterile saline used as control. After 16 weeks, the retinas were extracted and subjected to Evans blue leakage and retinal trypsin digestion assays. Retinal paraffin sections were prepared and stained with hematoxylin and eosin (H&E) or subjected to immunohistochemical or immunofluorescence assays.

RESULTS

Biacore, Langmuir equilibrium adsorption, and co-IP analyses demonstrated that the four designed THIPs specifically recognized hnRNPA2B1. CCK-8 and EdU labeling assays showed that the THIPs inhibited proliferation and DNA synthesis in hRECs under hyperglycemia. Transwell, wound healing and tube formation assays demonstrated that the THIPs inhibited the migratory and angiogenic capacity of hRECs. Quantitative PCR and western blot assays suggested that the THIPs exerted their effects via the STAT4/miR-223-3p/FBXW7 and the downstream Notch1/Akt/mTOR axes. In vivo studies using DR model rat revealed that the intravitreal administration of THIP-4 significantly mitigated retinal leakage, capillary decellularization, pericyte loss, fibrosis, and gliosis during DR progression.

CONCLUSION

Our findings demonstrated that under hyperglycemia, THIP-4 suppressed DR progression via the STAT4/miR-223-3p/FBXW7 and Notch1/Akt/mTOR axes both in vitro and in vivo. These results indicated that THIP-4 has strong potential for clinical application in DR and other angiogenesis associated diseases.

Curcumol ameliorates diabetic retinopathy via modulating fat mass and obesity-associated protein-demethylated MAF transcription factor G antisense RNA 1

BACKGROUND

Diabetic retinopathy (DR) is a major microvascular complication of diabetes mellitus, leading to significant visual impairment and blindness among adults. Current treatment options are limited, making it essential to explore novel therapeutic strategies. Curcumol, a sesquiterpenoid derived from traditional Chinese medicine, has shown anti-inflammatory and anti-cancer properties, but its potential role in DR remains unclear.

AIM

To investigate the therapeutic effects of curcumol on the progression of DR and to elucidate the underlying molecular mechanisms, particularly its impact on the fat mass and obesity-associated (FTO) protein and the long non-coding RNA (lncRNA) MAF transcription factor G antisense RNA 1 (MAFG-AS1).

METHODS

A streptozotocin-induced mouse model of DR was established, followed by treatment with curcumol. Retinal damage and inflammation were evaluated through histological analysis and molecular assays. Human retinal vascular endothelial cells were exposed to high glucose conditions to simulate diabetic environments in vitro. Cell proliferation, migration, and inflammation markers were assessed in curcumol-treated cells. LncRNA microarray analysis identified key molecules regulated by curcumol, and further experiments were conducted to confirm the involvement of FTO and MAFG-AS1 in the progression of DR.

RESULTS

Curcumol treatment significantly reduced blood glucose levels and alleviated retinal damage in streptozotocin-induced DR mouse models. In high-glucose-treated human retinal vascular endothelial cells, curcumol inhibited cell proliferation, migration, and inflammatory responses. LncRNA microarray analysis identified MAFG-AS1 as the most upregulated lncRNA following curcumol treatment. Mechanistically, FTO demethylated MAFG-AS1, stabilizing its expression. Rescue experiments demonstrated that the protective effects of curcumol against DR were mediated through the FTO/MAFG-AS1 signaling pathway.

CONCLUSION

Curcumol ameliorates the progression of DR by modulating the FTO/MAFG-AS1 axis, providing a novel therapeutic pathway for the treatment of DR. These findings suggest that curcumol-based therapies could offer a promising alternative for managing this debilitating complication of diabetes.

Non-coding RNA as a key regulator and novel target of apoptosis in diabetic cardiomyopathy: Current status and future prospects

The occurrence of diabetic cardiomyopathy (DCM) can be independent of several risk factors such as hypertension and myocardial ischemia, which can lead to heart failure, thus seriously threatening human health and life. Sustained hyperglycemic stimulation can induce cardiomyocyte apoptosis, which is recognized as the pathological basis of DCM. It has been demonstrated that dysregulation induced by apoptosis is closely associated to progression of DCM, but mechanisms behind it requires further clarification. Currently, increasing evidence has shown that non-coding RNA (ncRNA), especially microRNA, long-chain non-coding RNA (lncRNA), and circular RNA (circRNA), play a regulative role in apoptosis, thus affecting the progression of DCM. Notably, some ncRNAs have also exhibit potential significance as biomarkers and/or therapeutic targets for patients with DCM. In this review, recent findings regarding the potential mechanisms of ncRNA in regulating apoptosis and their role in the progression of DCM were systematically summarized in this research. The conclusion reveals that ncRNA abnormalities exert a crucial role in pathological changes of DCM, which offers potential therapeutic targets for the prevention of DCM.

RNA-based diagnostic innovations: A new frontier in diabetes diagnosis and management

Background/Objective: Diabetes mellitus (DM) remains a major global health challenge due to its chronic nature and associated complications. Traditional diagnostic approaches, though effective, often lack the sensitivity required for early-stage detection. Recent advancements in molecular biology have identified RNA molecules, particularly non-coding RNAs such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), as promising biomarkers for diabetes. This review aims to explore the role of RNA-based biomarkers in the diagnosis, prognosis, and management of diabetes, highlighting their potential to revolutionize diabetes care.Method: A comprehensive literature review was conducted using electronic databases including PubMed, Scopus, and Web of Science. Articles published up to 2024 were screened and analyzed to extract relevant findings related to RNA-based diagnostics in diabetes. Emphasis was placed on studies demonstrating clinical utility, mechanistic insights, and translational potential of RNA molecules.Results: Numerous RNA species, particularly miRNAs such as miR-375, miR-29, and lncRNAs like H19 and MEG3, exhibit altered expression patterns in diabetic patients. These molecules are involved in key regulatory pathways of glucose metabolism, insulin resistance, and β-cell function. Circulating RNAs are detectable in various biofluids, enabling non-invasive diagnostic approaches. Emerging technologies, including RNA sequencing and liquid biopsy platforms, have enhanced the sensitivity and specificity of RNA detection, fostering the development of novel diagnostic tools and personalized therapeutic strategies.Conclusion: RNA-based biomarkers hold significant promise in advancing early detection, risk stratification, and therapeutic monitoring in diabetes care. Despite current challenges such as standardization and clinical validation, the integration of RNA diagnostics into routine clinical practice could transform diabetes management, paving the way for precision medicine approaches. Further research and multi-center trials are essential to validate these biomarkers and facilitate their regulatory approval and clinical implementation.

LncRNA-mediated regulation of cisplatin response in breast cancer

Breast cancer is a prevalent and aggressive disease characterized by high metastasis, recurrence, and mortality rates. While cisplatin is an effective chemotherapy drug, its use is limited by its toxic effects on the body. Despite advancements in therapeutic strategies, the therapeutic response is often unsatisfactory due to drug resistance, leading to poor prognosis. Recent studies have shown that cisplatin interacts with long non-coding RNAs (lncRNAs) and accelerates the development of resistance in tumor cells to therapy. This interaction highlights the complex mechanisms involved in the response of cancer cells to chemotherapy. Several lncRNAs have been identified as key players in mediating cisplatin resistance in breast cancer. These lncRNAs include SNHG15, HULC, HCP5, MT1JP, LncMat2B, DLX6-ASL, Linc00665, CARMN, and Lnc-EinRP44-3:6. These lncRNAs have been shown to target microRNAs and mRNAs and modulate the expression of genes involved in cisplatin resistance, which is important in treating breast cancer.

The m6A-ncRNAs axis in diabetes complications: novel mechanism and therapeutic potential

Diabetes, a multifaceted metabolic disorder, poses a significant global health burden with its increasing prevalence and associated complications, such as diabetic nephropathy, diabetic retinopathy, diabetic cardiomyopathy, and diabetic angiopathy. Recent studies have highlighted the intricate interplay between N6-methyladenosine (m6A) and non-coding RNAs (ncRNAs) in key pathways implicated in these diabetes complications, like cell apoptosis, oxidative stress, and inflammation. Thus, understanding the mechanistic insights into how m6A dysregulation impacts the expression and function of ncRNAs opens new avenues for therapeutic interventions targeting the m6A-ncRNAs axis in diabetes complications. This review explores the regulatory roles of m6A modifications and ncRNAs, and stresses the role of the m6A-ncRNA axis in diabetes complications, providing a therapeutic potential for these diseases.

Preliminary research on LncRNA ATP2B2-IT2 in neovascularization of diabetic retinopathy

OBJECTIVE

Diabetic retinopathy (DR) is a common complication of diabetes, and recent findings have shown that long noncoding RNAs (lncRNAs) may be involved in its pathogenesis. Through bioinformatics analysis, we found that lncRNA ATP2B2-IT2 may be involved in this process. This study primarily investigated the expression of the lncRNA ATP2B2-IT2 in human retinal microvascular endothelial cells (HRMECs) under high-glucose conditions and its effects on HRMEC proliferation, migration, and neovascularization.

METHODS

We used RT‒PCR to assess the expression levels of lncRNA ATP2B2-IT2 and vascular endothelial growth factor (VEGF) in HRMECs under normal glucose (5.5 mmol/L) and high glucose (30 mmol/L) conditions. HRMECs were subsequently divided into four groups: the normal glucose (NG), high glucose (HG), high glucose with lncRNA ATP2B2-IT2 silencing (HG + si-lncRNA ATP2B2-IT2), and high glucose with silencing control (HG + si-NC) groups. The expression levels of the lncRNA ATP2B2-IT2 and VEGF in each group were determined using RT‒PCR. Thereafter, cell proliferation, migration, and neovascularization were assessed using CCK-8, Transwell, and tube formation assays, respectively.

RESULTS

RT‒PCR revealed that the expression levels of the lncRNA ATP2B2-IT2 and VEGF were greater in the HG group than in the NG group (P < 0.05). After silencing of the lncRNA ATP2B2-IT2, the expression of VEGF decreased significantly (P < 0.05). Subsequent CCK-8, Transwell, and tube formation assays demonstrated that compared to those in the NG group, the HRMECs in the HG group exhibited significantly increased proliferation, migration, and neovascularization (P < 0.05). However, after silencing of the lncRNA ATP2B2-IT2, the proliferation, migration, and neovascularization of HRMECs were significantly decreased in the HG + si-lncRNA ATP2B2-IT2 group compared to those in the HG group (P < 0.05).

CONCLUSION

LncRNA ATP2B2-IT2 may promote the proliferation, migration and neovascularization of HRMECs under high-glucose conditions.

STAT3-induced upregulation of lncRNA TTN-AS1 aggravates podocyte injury in diabetic nephropathy by promoting oxidative stress

Background

Diabetic nephropathy (DN) is the most common microvascular complication of diabetes mellitus (DM), being the second cause of end-stage renal disease globally. Podocyte injury is closely associated with DN developmen. Our study aimed to investigate the role of long non-coding RNA (lncRNA) TTN-AS1 in DN-associated podocyte injury.

Methods

The mouse podocyte cell line (MPC5) and human primary podocytes were stimulated by high glucose (HG; 30 nM glucose) to establish the cellular model of DN. Before HG stimulation, both podocytes were transfected with sh-TTN-AS1#1/2 or pcDNA3.1/STAT3 to evaluate the influence of TTN-AS1 knockdown or STAT3 overexpression on HG-induced podocyte injury. TTN-AS1 and STAT3 expression in both podocytes was examined by RT-qPCR. Cell viability and death were assessed by CCK-8 and LDH release assay. ELISA was adopted for testing IL-6 and TNF-α contents in cell supernatants. The levels of oxidative stress markers (ROS, MDA, SOD, and GSH) in cell supernatants were determined by commercial kits. Western blotting was used for measuring the expression of fibrosis markers (fibronectin and α-SMA and podocyte function markers (podocin and nephrin) in podocytes.

Results

HG stimulation led to decreased cell viability, increased cell death, fibrosis, inflammation, cell dysfunction and oxidative stress in podocytes. However, knockdown of TTN-AS1 ameliorated HG-induced podocyte injury. Mechanically, the transcription factor STAT3 interacted with TTN-AS1 promoter and upregulated TTN-AS1 expression. STAT3 overexpression offset the protective effect of TTN-AS1 silencing on HG-induced podocyte damage.

Conclusion

Overall, STAT3-mediated upregulation of lncRNA TTN-AS1 could exacerbate podocyte injury in DN through suppressing inflammation and oxidative stress.