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

The prevalence of a high-energy diet and a sedentary lifestyle has increased the incidence of type 2 diabetes (T2D). T2D is a chronic disease characterized by high blood glucose levels and insulin resistance in peripheral tissues. The pathological mechanism of this disease is not fully clear. Accumulated evidence has shown that noncoding RNAs have an essential regulatory role in the progression of diabetes and its complications. The roles of small noncoding RNAs, such as miRNAs, in T2D, have been extensively investigated, while the function of long noncoding RNAs (lncRNAs) in T2D has been unstudied. It has been reported that lncRNAs in T2D play roles in the regulation of pancreatic function, peripheral glucose homeostasis and vascular inflammation. In addition, lncRNAs carried by small extracellular vesicles (sEV) were shown to mediate communication between organs and participate in diabetes progression. Some sEV lncRNAs derived from stem cells are being developed as potential therapeutic agents for diabetic complications. In this review, we summarize the current knowledge relating to lncRNA biogenesis, the mechanisms of lncRNA sorting into sEV and the regulatory roles of lncRNAs and sEV lncRNAs in diabetes. Knowledge of lncRNAs and sEV lncRNAs in diabetes will aid in the development of new therapeutic drugs for T2D in the future.

Platelet Internalization Mediates Ferroptosis in Myocardial Infarction.

BACKGROUND: Myocardial cell death is the hallmark of myocardial infarction. In the process of myocardial injury, platelets contribute to the pathogenesis by triggering intense inflammatory responses. Yet, it is still unclear if platelets regulate cardiomyocyte death directly, thereby exacerbating myocardial injury in myocardial infarction. METHODS: We describe a mechanism underlying the correlative association between platelets accumulation and myocardial cell death by using myocardial infarction mouse model and patient specimens. RESULTS: Myocardial infarction induces platelets internalization, resulting in the release of miR-223-3p, a platelet-enriched miRNA. By targeting the ACSL3, miR-223-3p delivered by internalized platelets cause the reduction of stearic acid-phosphatidylcholine in cardiomyocytes. The presence of stearic acid-phosphatidylcholine protects cardiomyocytes against ferroptosis. CONCLUSIONS: Our work reveals a novel mechanism of platelet-mediated myocardial injury, highlighting antiplatelet therapies could potentially represent a multimechanism treatment of myocardial infarction, and implying ferroptosis being considered as novel target for therapeutics.

Light Chain Amyloidosis-Induced Autophagy Is Mediated by the Foxo3a/Beclin-1 Pathway in Cardiomyocytes.

Cardiac amyloidosis is a disease in which the extracellular space of the heart is deposited with and infiltrated by amyloid fibrillar material, and light chain (LC) amyloidosis (AL) is the most serious form of the disease. AL is caused by the overproduction and aggregation of monoclonal immunoglobulin LCs produced by bone marrow plasma cells. Studies have shown that the initial response at a subcellular level to the toxicity of AL is lysosomal dysfunction with impaired autophagy, elevated reactive oxygen species, cellular dysfunction, and cellular death. Therefore, we speculate that the multiple myeloma complicated by cardiac amyloidosis is due to the deposition of λ LC fibrils in cardiomyocytes, leading to dysregulation of autophagy and cell death. We constructed BACN1 siRNA or FOXO3A siRNA and transfected them into H9c2 cells. We detected changes in oxidative stress- and autophagy-related markers. Our results show that monoclonal immunoglobulin λ LCs can form amyloid aggregates, which are cytotoxic to cardiomyocytes. λ LC fibrils deposit on the cell surface, causing oxidative stress and excessive autophagy by increasing Beclin-1 expression and the LC3 II/LC3 I ratio and decreasing p62 expression, ultimately inducing cell death. Beclin-1 knockdown reversed the increase in the LC3 II/LC3 I ratio and the decrease in p62 induced by LC fibrils, while suppressing overactivated autophagy and oxidative stress. Furthermore, LCs reduce the expression of p-Foxo3a (Ser253) (inactive) and promote Foxo3a translocation into the nucleus to perform transcriptional activity, which induces autophagy-related gene overexpression. Silencing Foxo3a can suppress excessive autophagy induced by LC fibrils and protect cells from death. In summary, the results showed that the cytotoxicity of amyloid fibrils formed by λ LCs on cardiomyocytes is triggered by excessive autophagy and is mediated through the Foxo3a/Beclin-1 pathway.

Phosphatidylserine in Diabetes Research.

Phospholipids are lipids that constitute the basic structure of cell membranes. In-depth research has shown that in addition to supporting cell structures, phospholipids participate in multiple cellular processes, including promoting cell signal transduction, guiding protein translocation, activating enzymatic activity, and eliminating dysfunctional/redundant organelles/cells. Diabetes is a chronic metabolic disease with a complicated etiology and pathology. Studies have shown that the level of certain phospholipids, for example, the ratio of phosphatidylcholine (PC) to phosphatidylethanolamine (PE) in liver tissue, is negatively associated with insulin sensitivity. In addition, PS is a phospholipid exhibiting extensive cellular functions in diabetes. For this review, we analyzed many PS studies focusing on diabetes and insulin sensitivity in recent years and found that PS participates in controlling insulin secretion, regulating insulin signaling transduction, and participating in the progression of diabetic complications by mediating coagulation disorders in the microvasculature or targeting mitochondria. Moreover, PS supplements in food and PS-containing liposomes have been shown to protect against type 1 and type 2 diabetes (T1D and T2D, respectively) in animal studies. Therefore, by summarizing the regulatory roles played by PS in diabetes and the potential of successfully using PS or PS-containing liposomes for diabetic therapy, we hope to provide new ideas for further research into the mechanisms of diabetes and for drug development for treating diabetes and its complications.

Phospholipids in small extracellular vesicles: emerging regulators of neurodegenerative diseases and cancer.

Small extracellular vesicles (sEVs) are generated by almost all cell types. They have a bilayer membrane structure that is similar to cell membranes. Thus, the phospholipids contained in sEVs are the main components of cell membranes and function as structural support elements. However, as in-depth research on sEV membrane components is conducted, some phospholipids have been found to participate in cellular biological processes and function as targets for cell-cell communication. Currently, sEVs are being developed as part of drug delivery systems and diagnostic factors for various diseases, especially neurodegenerative diseases and cancer. An understanding of the physiological and pathological roles of sEV phospholipids in cellular processes is essential for their future medical application. In this review, the authors discuss phospholipid components in sEVs of different origins and summarize the roles of phospholipids in sEV biogenesis. The authors further collect the current knowledge on the functional roles of sEV phospholipids in cell-cell communication and bioactivities as signals regulating neurodegenerative diseases and cancer and the possibility of using sEV phospholipids as biomarkers or in drug delivery systems for cancer diagnosis and treatment. Knowledge of sEV phospholipids is important to help us identify directions for future studies.

Noncoding RNAs in doxorubicin-induced cardiotoxicity and their potential as biomarkers and therapeutic targets.

Anthracyclines, such as doxorubicin (DOX), are well known for their high efficacy in treating multiple cancers, but their clinical usage is limited due to their potential to induce fatal cardiotoxicity. Such detrimental effects significantly impact the overall physical condition or even induce the morbidity and mortality of cancer survivors. Therefore, it is extremely important to understand the mechanisms of DOX-induced cardiotoxicity to develop methods for the early detection of cytotoxicity and therapeutic applications. Studies have shown that many molecular events are involved in DOX-induced cardiotoxicity. However, the precise mechanisms are still not completely understood. Recently, noncoding RNAs (ncRNAs) have been extensively studied in a diverse range of regulatory roles in cellular physiological and pathological processes. With respect to their roles in DOX-induced cardiotoxicity, microRNAs (miRNAs) are the most widely studied, and studies have focused on the regulatory roles of long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs), which have been shown to have significant functions in the cardiovascular system. Recent discoveries on the roles of ncRNAs in DOX-induced cardiotoxicity have prompted extensive interest in exploring candidate ncRNAs for utilization as potential therapeutic targets and/or diagnostic biomarkers. This review presents the frontier studies on the roles of ncRNAs in DOX-induced cardiotoxicity, addresses the possibility and prospects of using ncRNAs as diagnostic biomarkers or therapeutic targets, and discusses the possible reasons for related discrepancies and limitations of their use.

Baicalein attenuates cardiac hypertrophy in mice via suppressing oxidative stress and activating autophagy in cardiomyocytes.

Baicalein is a natural flavonoid extracted from the root of Scutellaria baicalensis that exhibits a variety of pharmacological activities. In this study, we investigated the molecular mechanisms underlying the protective effect of baicalein against cardiac hypertrophy in vivo and in vitro. Cardiac hypertrophy was induced in mice by injection of isoproterenol (ISO, 30 mg·kg-1·d-1) for 15 days. The mice received caudal vein injection of baicalein (25 mg/kg) on 3rd, 6th, 9th, 12th, and 15th days. We showed that baicalein administration significantly attenuated ISO-induced cardiac hypertrophy and restored cardiac function. The protective effect of baicalein against cardiac hypertrophy was also observed in neonatal rat cardiomyocytes treated with ISO (10 µM). In cardiomyocytes, ISO treatment markedly increased reactive oxygen species (ROS) and inhibited autophagy, which were greatly alleviated by pretreatment with baicalein (30 µM). We found that baicalein pretreatment increased the expression of catalase and the mitophagy receptor FUN14 domain containing 1 (FUNDC1) to clear ROS and promote autophagy, thus attenuated ISO-induced cardiac hypertrophy. Furthermore, we revealed that baicalein bound to the transcription factor FOXO3a directly, promoting its transcription activity, and transactivated catalase and FUNDC1. In summary, our data provide new evidence for baicalein and FOXO3a in the regulation of ISO-induced cardiac hypertrophy. Baicalein has great potential for the treatment of cardiac hypertrophy.

The relationship between phospholipids and insulin resistance: From clinical to experimental studies.

Insulin resistance induced by high-fat diet and impropriate life style is a major contributor to the pathogenesis of metabolic disease. However, the underlying molecular mechanisms remain unclear. Recent studies in metabolic dysfunction have extended this beyond simply elevated cholesterol and triglycerides levels and have identified a key role for lipid metabolism. For example, altered phospholipid metabolism has now become central in the pathogenesis of metabolic disease. In this review, we discuss the association between insulin sensitivity and phospholipid metabolism and highlight the most significant discoveries generated over the last several decades. Finally, we summarize the current knowledge surrounding the molecular mechanisms related to phospholipids and insulin resistance and provide new insight for future research into their relationship.

Circulating miR-22-5p and miR-122-5p are promising novel biomarkers for diagnosis of acute myocardial infarction.

BACKGROUND/AIMS: This study sought to evaluate the potential of circulating microRNAs (miRNAs) as novel indicators for acute myocardial infarction (AMI). METHODS: Plasma samples were collected from each participant, and total RNA was extracted. Quantitative real-time polymerase chain reaction were used to investigate the expression of circulating miRNAs. We measured circulating levels of six individual miRNAs, which are known to be relevant to AMI, in the plasma samples from 66 AMI patients and 70 non-AMI healthy comparisons. RESULTS: Five small RNAs were specifically expressed in AMI patients, plasma miR-122-5p levels is significantly elevated (p < 0.0001) in AMI patients, while plasma miR-22-5p ( p < 0.05) levels were significantly decreased. In addition, significant correlations between miR-22-5p and miR-122-5p ( R = 0.773), miR-122-5p and creatine kinase isoenzyme (CK-MB; R = 0.6296) were detected. Further, receiver operating characteristic (ROC) analysis indicated that miR-22-5p showed considerable diagnostic efficiency for predicting AMI (area under the curve [AUC] = 0.975). Combining miR-22-5p and miR-122-5p in a panel increased the sensitivity (98.6%) of distinguishing between patients with AMI and healthy comparisons. CONCLUSION: Circulating miR-22-5p and miR-122-5p could be considered promising novel diagnostic biomarkers for AMI.

A review of sources, multimedia distribution and health risks of novel fluorinated alternatives.

Per- and polyfluoroalkyl substances (PFASs) are a class of emerging persistent organic pollutants (POPs). They are widely used in industrial and consumer applications. Due to their persistence, bioaccumulation, long-distance migration and toxicity, it is important to find new compounds that can replace PFASs. The present review investigated the sources, fates and environmental effects of alternative PFAS compounds using surveys have been conducted over the past several years. Concentrations of PFAS alternatives in various environmental media, as well as human tissues, are summarized based on the available data. The results showed that hexafluoropropylene oxide dimer (HFPO-DA), hexafluoropropylene trimer acids (HFPO-TA), and 6:2 chlorinated polyfluorinated ether sulfonic acid (6:2 Cl-PFESA) have become the dominant global perfluorinated pollutants. Currently, there are a few toxicity assessments of these novel fluorinated alternatives, showing that they have systemic multiple organ toxicities. PFAS alternatives exhibited comparable or even more serious potential toxicity than legacy PFASs, indicating that these fluorinated alternatives are also harmful to the environment. Therefore, these alternatives require additional toxicological studies to confirm whether they can be used for a long time.

Prox1 is essential for oligodendrocyte survival and regulates oligodendrocyte apoptosis via the regulation of NOXA.

Demyelinating diseases, such as multiple sclerosis, are known to result from acute or chronic injury to the myelin sheath and inadequate remyelination. Its underlying molecular mechanisms, however, remain unclear. The transcription factor prospero homeobox 1 (Prox1) plays an essential role during embryonic development of the central nervous system and cell differentiation. Thus, we aimed to investigate the role of Prox1 in the survival and differentiation of oligodendrocytes. Cell viability was measured by MTT assay. Flow cytometry was conducted to analyze cell apoptosis. Ectopic-Prox1 and shProx1 were used for the overexpression and knockdown respectively of Prox1 in FBD-102b cells. Real-time reverse transcriptase polymerase chain reaction and western blot analysis were used to assess the alterations of signaling pathway-related mRNAs and proteins, respectively. Results showed that Prox1 was upregulated in differentiating oligodendrocytes, and Prox1 knockdown inhibited the differentiation of oligodendrocytes. In addition, overexpression of Prox1 promoted oligodendrocyte differentiation, as shown by the change in myelin basic protein expression. The overexpression of Prox1 had no effect on oligodendrocyte survival, while Prox1 knockdown impaired cell survival. Further study demonstrated that Prox1 knockdown promoted oligodendrocyte apoptosis and activated NOXA, a pro-apoptotic member of the Bcl-2 protein family. Knockdown of NOXA by siRNA abrogated Prox1 knockdown-induced apoptosis. Our findings indicated that Prox1 regulated the differentiation of oligodendrocyte precursor cells via the regulation of NOXA. Therefore, Prox1 could be a potential modulator of demyelinating diseases in clinical settings.

Berberine treatment attenuates the palmitate-mediated inhibition of glucose uptake and consumption through increased 1,2,3-triacyl-sn-glycerol synthesis and accumulation in H9c2 cardiomyocytes.

Dysfunction of lipid metabolism and accumulation of 1,2-diacyl-sn-glycerol (DAG) may be a key factor in the development of insulin resistance in type 2 diabetes. Berberine (BBR) is an isoquinoline alkaloid extract that has shown promise as a hypoglycemic agent in the management of diabetes in animal and human studies. However, its mechanism of action is not well understood. To determine the effect of BBR on lipid synthesis and its relationship to insulin resistance in H9c2 cardiomyocytes, we measured neutral lipid and phospholipid synthesis and their relationship to glucose uptake. Compared with controls, BBR treatment stimulated 2-[1,2-(3)H(N)]deoxy-D-glucose uptake and consumption in palmitate-mediated insulin resistant H9c2 cells. The mechanism was though an increase in protein kinase B (AKT) activity and GLUT-4 glucose transporter expression. DAG accumulated in palmitate-mediated insulin resistant H9c2 cells and treatment with BBR reduced this DAG accumulation and increased accumulation of 1,2,3-triacyl-sn-glycerol (TAG) compared to controls. Treatment of palmitate-mediated insulin resistant H9c2 cells with BBR increased [1,3-(3)H]glycerol and [1-(14)C]glucose incorporation into TAG and reduced their incorporation into DAG compared to control. In addition, BBR treatment of these cells increased [1-(14)C]palmitic acid incorporation into TAG and decreased its incorporation into DAG compared to controls. BBR treatment did not alter phosphatidylcholine or phosphatidylethanolamine synthesis. The mechanism for the BBR-mediated decreased precursor incorporation into DAG and increased incorporation into TAG in palmitate-incubated cells was an increase in DAG acyltransferase-2 activity and its expression and a decrease in TAG hydrolysis. Thus, BBR treatment attenuates palmitate-induced reduction in glucose uptake and consumption, in part, through reduction in cellular DAG levels and accumulation of TAG in H9c2 cells.

Reduction in cardiolipin decreases mitochondrial spare respiratory capacity and increases glucose transport into and across human brain cerebral microvascular endothelial cells.

Microvessel endothelial cells form part of the blood-brain barrier, a restrictively permeable interface that allows transport of only specific compounds into the brain. Cardiolipin is a mitochondrial phospholipid required for function of the electron transport chain and ATP generation. We examined the role of cardiolipin in maintaining mitochondrial function necessary to support barrier properties of brain microvessel endothelial cells. Knockdown of the terminal enzyme of cardiolipin synthesis, cardiolipin synthase, in hCMEC/D3 cells resulted in decreased cellular cardiolipin levels compared to controls. The reduction in cardiolipin resulted in decreased mitochondrial spare respiratory capacity, increased pyruvate kinase activity, and increased 2-deoxy-[(3) H]glucose uptake and glucose transporter-1 expression and localization to membranes in hCMEC/D3 cells compared to controls. The mechanism for the increase in glucose uptake was an increase in adenosine-5'-monophosphate kinase and protein kinase B activity and decreased glycogen synthase kinase 3 beta activity. Knockdown of cardiolipin synthase did not affect permeability of fluorescent dextran across confluent hCMEC/D3 monolayers grown on Transwell(®) inserts. In contrast, knockdown of cardiolipin synthase resulted in an increase in 2-deoxy-[(3) H]glucose transport across these monolayers compared to controls. The data indicate that in hCMEC/D3 cells, spare respiratory capacity is dependent on cardiolipin. In addition, reduction in cardiolipin in these cells alters their cellular energy status and this results in increased glucose transport into and across hCMEC/D3 monolayers. Microvessel endothelial cells form part of the blood-brain barrier, a restrictively permeable interface that allows transport of only specific compounds into the brain. In human adult brain endothelial cell hCMEC/D3 monolayers cultured on Transwell(®) plates, knockdown of cardiolipin synthase results in decrease in mitochondrial cardiolipin and decreased mitochondrial spare respiratory capacity. The reduced cardiolipin results in an increased activity of adenosine monophosphate kinase (pAMPK) and protein kinase B (pAKT) and decreased activity of glycogen synthase kinase 3 beta (pGSK3ß) which results in elevated glucose transporter-1 (GLUT-1) expression and association with membranes. This in turn increases 2-dexoyglucose uptake from the apical medium into the cells with a resultant 2-deoxyglucose movement into the basolateral medium.

The antioxidant edaravone prevents cardiac dysfunction by suppressing oxidative stress in type 1 diabetic rats and in high-glucose-induced injured H9c2 cardiomyoblasts.

Edaravone, a radical scavenger, has been recognized as a potential protective agent for cardiovascular diseases. However, little is known about the effect of edaravone in cardiac complications associated with diabetes. Here, we have demonstrated that edaravone prevents cardiac dysfunction and apoptosis in the streptozotocin-induced type 1 diabetic rat heart. Mechanistic studies revealed that edaravone treatment improved cardiac function and restored superoxide dismutase levels. In addition, treatment of diabetic animals by edaravone increased protein expressions of sirtuin-1 (SIRT-1), peroxisome proliferator activated receptor γ coactivator α (PGC-1α), nuclear factor like-2 (NRF-2), and B cell lymphoma 2 (Bcl-2), and reduced protein expressions of Bax and Caspase-3 compared to the control group. High glucose incubation resulted in the production of reactive oxygen species (ROS) and cell death. Treatment of high-glucose-incubated H9c2 cells by edaravone reduced ROS production and cell death. In addition, the treatment of high-glucose-incubated H9c2 cells by edaravone increased the activity of antioxidative stress by increasing SIRT-1, PGC-1α, and NRF-2, and this treatment also reduced apoptosis by increasing Bcl-2 expression and reducing Bax and Caspase-3 expressions. Knockdown SIRT-1 with small interferer RNA abolished the effects of edaravone. Overall, our data demonstrated that edaravone may be an effective agent against the development of diabetic cardiomyopathy.

Berberine as a therapy for type 2 diabetes and its complications: From mechanism of action to clinical studies.

The incidence of type 2 diabetes is increasing rapidly worldwide, and the development of novel anti-diabetic drugs is emerging. However, most anti-diabetic drugs cannot be used in patients with hepatic dysfunction, renal disease, and heart disease, which makes pharmacological therapy of type 2 diabetes complicated. Despite continued introduction of novel agents, the search for an ideal drug that is useful as both a hypoglycemic agent and to reduce diabetes-related complications remains elusive. Berberine is an isoquinoline alkaloid extract that has shown promise as a hypoglycemic agent in the management of diabetes in animal and human studies. Mechanistic studies have revealed beneficial effects of berberine on diabetes-related complications. Although there have been few clinical reports of the anti-diabetic effects of berberine, little documentation of adverse effects in humans positions it as a potential candidate drug to treat type 2 diabetes. In the present review, the anti-diabetic mechanism of berberine, its effect on diabetes-related complications, and its recent use in human clinical studies is highlighted. In addition, we summarize the different treatments for type 2 diabetes in adults and children.

Oxidative modification of miR-30c promotes cardiac fibroblast proliferation via CDKN2C mismatch.

The response of cardiac fibroblast proliferation to detrimental stimuli is one of the main pathological factors causing heart remodeling. Reactive oxygen species (ROS) mediate the proliferation of cardiac fibroblasts. However, the exact molecular mechanism remains unclear. In vivo, we examined the oxidative modification of miRNAs with miRNA immunoprecipitation with O8G in animal models of cardiac fibrosis induced by Ang II injection or ischemia‒reperfusion injury. Furthermore, in vitro, we constructed oxidation-modified miR-30c and investigated its effects on the proliferation of cardiac fibroblasts. Additionally, luciferase reporter assays were used to identify the target of oxidized miR-30c. We found that miR-30c oxidation was modified by Ang II and PDGF treatment and mediated by excess ROS. We demonstrated that oxidative modification of G to O8G occurred at positions 4 and 5 of the 5' end of miR-30c (4,5-oxo-miR-30c), and this modification promoted cardiac fibroblast proliferation. Furthermore, CDKN2C is a negative regulator of cardiac fibroblast proliferation. 4,5-oxo-miR-30c misrecognizes CDKN2C mRNA, resulting in a reduction in protein expression. Oxidized miR-30c promotes cardiac fibroblast proliferation by mismatch mRNA of CDKN2C.

Copper and Diabetes: Current Research and Prospect.

Copper is an essential trace metal for normal cellular functions; a lack of copper is reported to impair the function of important copper-binding enzymes, while excess copper could lead to cell death. Numerous studies have shown an association between dietary copper consumption or plasma copper levels and the incidence of diabetes/diabetes complications. And experimental studies have revealed multiple signaling pathways that are triggered by copper shortages or copper overload in diabetic conditions. Moreover, studies show that treated with copper chelators improve vascular function, maintain copper homeostasis, inhibit cuproptosis, and reduce cell toxicity, thereby alleviating diabetic neuropathy, retinopathy, nephropathy, and cardiomyopathy. However, the mechanisms reported in these studies are inconsistent or even contradictory. This review summarizes the precise and tight regulation of copper homeostasis processes, and discusses the latest progress in the association of diabetes and dietary copper/plasma copper. Further, the study pays close attention to the therapeutic potential of copper chelators and copper in diabetes and its complications, and hopes to provide new insight for the treatment of diabetes.

The anti-diabetic effects of metformin are mediated by regulating long non-coding RNA.

Type 2 diabetes (T2D) is a metabolic disease with complex etiology and mechanisms. Long non-coding ribonucleic acid (LncRNA) is a novel class of functional long RNA molecules that regulate multiple biological functions through various mechanisms. Studies in the past decade have shown that lncRNAs may play an important role in regulating insulin resistance and the progression of T2D. As a widely used biguanide drug, metformin has been used for glucose lowering effects in clinical practice for more than 60 years. For diabetic therapy, metformin reduces glucose absorption from the intestines, lowers hepatic gluconeogenesis, reduces inflammation, and improves insulin sensitivity. However, despite being widely used as the first-line oral antidiabetic drug, its mechanism of action remains largely elusive. Currently, an increasing number of studies have demonstrated that the anti-diabetic effects of metformin were mediated by the regulation of lncRNAs. Metformin-regulated lncRNAs have been shown to participate in the inhibition of gluconeogenesis, regulation of lipid metabolism, and be anti-inflammatory. Thus, this review focuses on the mechanisms of action of metformin in regulating lncRNAs in diabetes, including pathways altered by metformin via targeting lncRNAs, and the potential targets of metformin through modulation of lncRNAs. Knowledge of the mechanisms of lncRNA modulation by metformin in diabetes will aid the development of new therapeutic drugs for T2D in the future.

Decreased in n-3 DHA enriched triacylglycerol in small extracellular vesicles of diabetic patients with cardiac dysfunction.

PURPOSE: Diabetic cardiomyopathy is the leading cause of death in diabetic patients, and the mechanism by which factors other than hyperglycemia contribute to the development of diabetic cardiomyopathy is unknown. Serum small extracellular vesicles (sEVs) carry bioactive proteins or nuclei, which enter into remote tissues and modulate cell functions. However, in diabetic conditions, the changes of lipids carried by sEVs has not been identified. Our study aims to explore the changes of lipids in sEVs in diabetic patients with cardiovascular disease, we hope to provide new ideas for understanding the role of lipid metabolism in the pathogenesis of diabetic cardiomyopathy. METHODS: SEVs samples derived from serum of health controls (Ctrl), diabetic patients without cardiovascular diseases (DM), and diabetic patients with cardiovascular diseases (DM-CAD) were used for lipidomics analysis. Because AC16 cells are also treated with those sEVs to confirm the entrance of cells and effects on insulin sensitivity, a lipidomics analysis on cells was also performed. RESULTS AND CONCLUSIONS: In this study, we found that docosahexaenoic acid (DHA)-triacylglycerides of sEVs from serums of DM-CAD patients decreased significantly, and those sEVs could enter into AC16 cells and diminish insulin sensitivity. In addition, DHA-triacylglycerides were also decreased in cells treated with sEVs from DM-CAD. Therefore, DHA-triacylglycerides carried by sEVs may mediate intercellular signaling and be associated with the incidence of diabetic cardiovascular complications.

The relationship between gut microbiota and COVID-19 progression: new insights into immunopathogenesis and treatment.

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has posed a global health crisis. Increasing evidence underlines the key role of competent immune responses in resisting SARS-CoV-2 infection and manifests the disastrous consequence of host immune dysregulation. Elucidating the mechanisms responsible for deregulated host immunity in COVID-19 may provide a theoretical basis for further research on new treatment modalities. Gut microbiota comprises trillions of microorganisms colonizing the human gastrointestinal tract and has a vital role in immune homeostasis and the gut-lung crosstalk. Particularly, SARS-CoV-2 infection can lead to the disruption of gut microbiota equilibrium, a condition called gut dysbiosis. Due to its regulatory effect on host immunity, gut microbiota has recently received considerable attention in the field of SARS-CoV-2 immunopathology. Imbalanced gut microbiota can fuel COVID-19 progression through production of bioactive metabolites, intestinal metabolism, enhancement of the cytokine storm, exaggeration of inflammation, regulation of adaptive immunity and other aspects. In this review, we provide an overview of the alterations in gut microbiota in COVID-19 patients, and their effects on individuals' susceptibility to viral infection and COVID-19 progression. Moreover, we summarize currently available data on the critical role of the bidirectional regulation between intestinal microbes and host immunity in SARS-CoV-2-induced pathology, and highlight the immunomodulatory mechanisms of gut microbiota contributing to COVID-19 pathogenesis. In addition, we discuss the therapeutic benefits and future perspectives of microbiota-targeted interventions including faecal microbiota transplantation (FMT), bacteriotherapy and traditional Chinese medicine (TCM) in COVID-19 treatment.