lncRNA uc.48+ regulates immune and inflammatory reactions mediated by the P2X7 receptor in type 2 diabetic mice

LncRNA NEAT1 aggravates human microvascular endothelial cell injury by inhibiting the Apelin/Nrf2/HO-1 signalling pathway in type 2 diabetes mellitus with obstructive sleep apnoea

Long noncoding RNAs (lncRNAs) regulate the progression of type 2 diabetes mellitus complicated with obstructive sleep apnoea (T2DM-OSA). However, the role of the lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) in T2DM-OSA remains unknown. This study aimed to reveal the function of NEAT1 in T2DM-OSA and the underlying mechanism. KKAy mice were exposed to intermittent hypoxia (IH) or intermittent normoxia to generate a T2DM-OSA mouse model. HMEC-1 cells were treated with high glucose (HG) and IH to construct a T2DM-OSA cell model. RNA expression was detected by qRT-PCR. The protein expression of Apelin, NF-E2-related factor 2 (Nrf2), haem oxygenase-1 (HO-1), and up-frameshift suppressor 1 (UPF1) was assessed using western blot. Cell injury was evaluated using flow cytometry, enzyme-linked immunosorbent assay, and oxidative stress kit assays. RIP, RNA pull-down, and actinomycin D assays were performed to determine the associations between NEAT1, UPF1, and Apelin. NEAT1 expression was upregulated in the aortic vascular tissues of mice with T2DM exposed to IH and HMEC-1 cells stimulated with HG and IH, whereas Apelin expression was downregulated. The absence of NEAT1 protected HMEC-1 cells from HG- and IH-induced damage. Furthermore, NEAT1 destabilized Apelin mRNA by recruiting UPF1. Apelin overexpression decreased HG- and IH-induced injury to HMEC-1 cells by activating the Nrf2/HO-1 pathway. Moreover, NEAT1 knockdown reduced HG- and IH-induced injury to HMEC-1 cells through Apelin. NEAT1 silencing reduced HMEC-1 cell injury through the Apelin/Nrf2/HO-1 signalling pathway in T2DM-OSA.Abbreviations: LncRNAs, long non-coding RNAs; T2DM, type 2 diabetes mellitus; OSA, obstructive sleep apnoea; NEAT1, nuclear paraspeckle assembly transcript 1; IH, intermittent hypoxia; HMEC-1, human microvascular endothelial cells; HG, high glucose; Nrf2, NF-E2-related factor 2; UPF1, up-frameshift suppressor 1; HO-1, haem oxygenase-1; qRT-PCR, quantitative real-time polymerase chain reaction; ELISA, enzyme-linked immunosorbent assay; GAPDH, glyceraldehyde 3-phosphate dehydrogenase; TNF-α, tumour necrosis factor-α; CCK-8, Cell Counting Kit-8; IL-1β, interleukin-1β; ROS, reactive oxygen species; MDA, malondialdehyde; SOD, superoxide dismutase; RIP, RNA immunoprecipitation; SD, standard deviations; GSH, glutathione; AIS, acute ischaemic stroke; HMGB1, high mobility group box-1 protein; TLR4, toll-like receptor 4.

Non-coding RNAs in diabetic foot ulcer- a focus on infected wounds

Diabetes mellitus is associated with a wide range of neuropathies, vasculopathies, and immunopathies, resulting in many complications. More than 30% of diabetic patients risk developing diabetic foot ulcers (DFUs). Non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), play essential roles in various biological functions in the hyperglycaemic environment that determines the development of DFU. Ulceration results in tissue breakdown and skin barrier scavenging, thereby facilitating bacterial infection and biofilm formation. Many bacteria contribute to diabetic foot infection (DFI), including Staphylococcus aureus (S. aureus) et al. A heterogeneous group of "ncRNAs," termed small RNAs (sRNAs), powerfully regulates biofilm formation and DFI healing. Multidisciplinary foot care interventions have been identified for nonhealing ulcers. With an appreciation of the link between disease processes and ncRNAs, a novel therapeutic model of bioactive materials loaded with ncRNAs has been developed to prevent and manage diabetic foot complications.

Macrophage lncRNAs in cancer development: Long-awaited therapeutic targets

In the tumor microenvironment, the interplay among macrophages, cancer cells, and endothelial cells is multifaceted. Tumor-associated macrophages (TAMs), which often exhibit an M2 phenotype, contribute to tumor growth and angiogenesis, while cancer cells and endothelial cells reciprocally influence macrophage behavior. This complex interrelationship highlights the importance of targeting these interactions for the development of novel cancer therapies aimed at disrupting tumor progression and angiogenesis. Accumulating evidence underscores the indispensable involvement of lncRNAs in shaping macrophage functionality and contributing to the development of cancer. Animal studies have further validated the therapeutic potential of manipulating macrophage lncRNA activity to ameliorate disease severity and reduce morbidity rates. This review provides a survey of our current understanding of macrophage-associated lncRNAs, with a specific emphasis on their molecular targets and their regulatory impact on cancer progression. These lncRNAs predominantly govern macrophage polarization, favoring the dominance of M2 macrophages or TAMs. Exosomes or extracellular vesicles mediate lncRNA transfer between macrophages and cancer cells, affecting cellular functions of each other. Moreover, this review presents therapeutic strategies targeting cancer-associated lncRNAs. The insights and findings presented in this review pertaining to macrophage lncRNAs can offer valuable information for the development of treatments against cancer.

Circulating Levels of HOTAIR- lncRNA Are Associated with Disease Progression and Clinical Parameters in Type 2 Diabetes Patients

Background

Recent studies have implicated dysregulated long non-coding RNA (lncRNA) levels in the pathogenesis of type 2 diabetes (T2D). This study aimed to assess the expression of circulating HOTAIR and uc.48+, examining their correlation with clinical and biochemical variables in T2D patients, pre-diabetic individuals, and healthy controls.

Methods

Peripheral blood levels of lncRNAs were quantified using QRT-PCR in 65 T2D patients, 63 pre-diabetic individuals, and 63 healthy subjects. Pathway enrichment analysis was conducted to explore the functional enrichment of lncRNA-miRNA targets.

Results

Analysis revealed a significantly elevated circulating level of HOTAIR in both T2D (P < 0.0001) and pre-diabetic patients (P = 0.04) compared to controls. ROC analysis demonstrated that, at a cutoff value of 9.1, with a sensitivity of 80% and specificity of 62%, HOTAIR could distinguish T2D patients from controls (AUC = 0.723, 95% CI 0.637-0.799, P < 0.0001). Spearman correlation analysis identified a significant positive correlation between HOTAIR expression, HbA1c, and insulin resistance (P < 0.005). MiRNA enrichment analysis indicated significant enrichment of diabetes-related pathways among HOTAIR's miRNA targets. Conversely, no significant difference in uc.48+ circulating levels between groups was observed, but a significant positive correlation emerged between uc.48+ and systolic blood pressure.

Conclusions

This study provides evidence that elevated HOTAIR expression levels are associated with T2D progression, suggesting their potential as biomarkers for early diagnosis and prognosis.

Ultra-conserved RNA: a novel biological tool with diagnostic and therapeutic potential

Ultra-conserved RNA (ucRNA) is a subset of long non-coding RNA, that is highly conserved among mice, rats and humans. UcRNA has attracted extensive attention in recent years for its potential biological significance in normal physiological function and diseases. However, due to the instability of RNA and the technical limitation, the function and mechanism of ucRNAs are largely unknown. Over the last two decades, researchers have made a lot of efforts to try to lift the veil of ucRNA in nervous, cardiovascular system and other systems as well as cancers. Since the concept of the glymphatic system is relatively new, we summarized here recent findings on the functions, regulation and the underlying mechanisms of ucRNAs in physiology and pathology. Meanwhile, pathology in some diseases is likely to contribute to abnormal expression of ucRNA in turn. We also discuss the technical challenges and bright prospects for future applications of ucRNAs in the diagnosis and treatment of diseases.

A novel definition and treatment of hyperinflammation in COVID-19 based on purinergic signalling

Hyperinflammation plays an important role in severe and critical COVID-19. Using inconsistent criteria, many researchers define hyperinflammation as a form of very severe inflammation with cytokine storm. Therefore, COVID-19 patients are treated with anti-inflammatory drugs. These drugs appear to be less efficacious than expected and are sometimes accompanied by serious adverse effects. SARS-CoV-2 promotes cellular ATP release. Increased levels of extracellular ATP activate the purinergic receptors of the immune cells initiating the physiologic pro-inflammatory immune response. Persisting viral infection drives the ATP release even further leading to the activation of the P2X7 purinergic receptors (P2X7Rs) and a severe yet physiologic inflammation. Disease progression promotes prolonged vigorous activation of the P2X7R causing cell death and uncontrolled ATP release leading to cytokine storm and desensitisation of all other purinergic receptors of the immune cells. This results in immune paralysis with co-infections or secondary infections. We refer to this pathologic condition as hyperinflammation. The readily available and affordable P2X7R antagonist lidocaine can abrogate hyperinflammation and restore the normal immune function. The issue is that the half-maximal effective concentration for P2X7R inhibition of lidocaine is much higher than the maximal tolerable plasma concentration where adverse effects start to develop. To overcome this, we selectively inhibit the P2X7Rs of the immune cells of the lymphatic system inducing clonal expansion of Tregs in local lymph nodes. Subsequently, these Tregs migrate throughout the body exerting anti-inflammatory activities suppressing systemic and (distant) local hyperinflammation. We illustrate this with six critically ill COVID-19 patients treated with lidocaine.

LncRNA PTGS2 regulates islet β-cell function through the miR-146a-5p/RBP4 axis and its diagnostic value in type 2 diabetes mellitus

OBJECTIVE

To investigate the effect of long non-coding RNA (LncRNA) PTGS2 on islet β-cell function via the miR-146a-5p/Retinol binding protein 4 (RBP4) axis and its diagnostic value in type 2 diabetes mellitus (T2DM).

METHODS

The Gene Expression Omnibus (GEO) was analyzed and LncRNA PTGS2 was identified as a potential regulator of T2DM. Mouse pancreatic β cell INS-1 cells were cultured with high glucose, and the relative expression of LncRNA PTGS2 in the serum of T2DM patients and INS-1 cells was detected by Fluorescence Quantitative PCR (qRT-PCR) and its diagnostic value for T2DM was analyzed. The PTGS2/miR-146a-5p/RBP4 axis in INS-1 cells was intervened to observe the changes in cell function. The proliferation of INS-1 cells was detected by CCK8, and the level of insulin secretion was detected by enzyme linked immunosorbent assay (ELISA). The regulatory relationship among LncRNA PTGS2, miR-146a-5p and RBP4 was determined by dual-luciferase reporter assay.

RESULTS

The expression of LncRNA PTGS2 in the serum of T2DM patients increased, and the expression of LncRNA PTGS2 was positively correlated with the fasting blood glucose level of patients (R=0.306, P<0.05). Knockdown of LncRNA PTGS2 could promote the proliferation and insulin secretion of INS-1 cells, while overexpression of LncRNA PTGS2 showed the opposite results (all P<0.05). Knockdown of LncRNA PTGS2 could up-regulate the expression of miR-146a-5p. Overexpression of LncRNA PTGS2 inhibited the proliferation and insulin secretion of INS-1 cells, while miR-146a-5p could partially reverse this effect. RBP4 has been identified as a downstream target gene of miR-146a-5p. Overexpression of miR-146a-5p could inhibit the expression of RBP4, which was positively correlated withLncRNA PTGS2 regulation. The effect of RBP4 on INS-1 cells was the same as that of LncRNA PTGS2.

CONCLUSION

LncRNA PTGS2 can damage islet β-cell function by regulation of miR-146a-5p and up-regulation of RBP4. LncRNA PTGS2 has potential value in the diagnosis of T2DM.

Interleukin-1β in Multifactorial Hypertension: Inflammation, Vascular Smooth Muscle Cell and Extracellular Matrix Remodeling, and Non-Coding RNA Regulation

The biological activities of interleukins, a group of circulating cytokines, are linked to the immuno-pathways involved in many diseases. Mounting evidence suggests that interleukin-1β (IL-1β) plays a significant role in the pathogenesis of various types of hypertension. In this review, we summarized recent findings linking IL-1β to systemic arterial hypertension, pulmonary hypertension, and gestational hypertension. We also outlined the new progress in elucidating the potential mechanisms of IL-1β in hypertension, focusing on it's regulation in inflammation, vascular smooth muscle cell function, and extracellular remodeling. In addition, we reviewed recent studies that highlight novel findings examining the function of non-coding RNAs in regulating the activity of IL-1β and its associated proteins in the setting of hypertension. The information collected in this review provides new insights into understanding the pathogenesis of hypertension and could lead to the discovery of new anti-hypertensive therapies to combat this highly prevalent disease.

Molecular Mechanisms and Functions of lncRNAs in the Inflammatory Reaction of Diabetes Mellitus

Diabetes is a chronic inflammatory state, and several studies have shown that the mechanisms of insulin resistance and abnormal islet β-cell function in diabetes are closely related to inflammatory reactions. Inflammation plays a critical role in diabetic complications. Long noncoding RNAs (lncRNAs), a new area of genomic research for gene regulation, have complex biological functions in various aspects of cellular biological activity. Recent studies have shown that lncRNAs are associated with the regulation of inflammatory responses in various ways, including at the epigenetic, transcriptional, and posttranscriptional levels. This paper presents a brief review of studies on the mechanisms of lncRNAs in diabetic inflammation. The purpose of this article is to determine the role of lncRNAs in the process of diabetic inflammation and to provide new strategies for the use of lncRNAs in the treatments for diabetic inflammation.