Silencing long non-coding RNA Kcnq1ot1 alleviates pyroptosis and fibrosis in diabetic cardiomyopathy

The lncRNA HOTAIR attenuates pyroptosis of diabetic cardiomyocytes by recruiting FUS to regulate SIRT3 expression

Diabetic cardiomyopathy (DCM) is a serious cardiovascular complication of diabetes that severely affects the quality of life of diabetic patients. Long noncoding RNAs (lncRNAs) play important roles in the pathogenesis of DCM. However, the role of the lncRNA homeobox transcript antisense RNA (HOTAIR) in the progression of DCM remains unclear. The present study aimed to investigate the role of HOTAIR in high glucose (HG)-induced pyroptosis in cardiomyocytes. The expression of the lncRNA HOTAIR, FUS, and SIRT3 in H9C2 cardiomyocytes was detected by RT-qPCR. Western blotting was used to evaluate the expression of FUS and SIRT3 as well as that of pyroptosis- and inflammation-related proteins. RT-qPCR and ELISA were used to determine the expression and secretion of IL-1β and IL-18. RNA pulldown and RIP experiments were used to validate the binding relationship among HOTAIR, FUS, and SIRT3. Flow cytometry was performed to detect pyroptosis. HG induced pyroptosis and elevated the expression of proteins associated with pyroptosis and inflammation (NLRP3, GSDMD-N, cleaved caspase-1, IL-1β, and IL-18) in cardiomyocytes. HOTAIR and SIRT3 levels were decreased in HG-exposed H9C2 cells. Additionally, overexpression of HOTAIR inhibited the HG-induced pyroptosis and inflammatory response in cardiomyocytes. HOTAIR upregulated SIRT3 expression in H9C2 cells by targeting FUS. Moreover, SIRT3 upregulation suppressed HG-mediated pyroptosis of cardiomyocytes. Notably, SIRT3 depletion reversed the inhibitory effect of HOTAIR on HG-triggered pyroptosis in cardiomyocytes. Our research indicates that HOTAIR alleviates pyroptosis in diabetic cardiomyocytes through the FUS/SIRT3 axis, providing a potential marker for the diagnosis and treatment of DCM.

Ferroptosis, necroptosis and cuproptosis: Novel forms of regulated cell death in diabetic cardiomyopathy

Diabetes is a common chronic metabolic disease, and its incidence continues to increase year after year. Diabetic patients mainly die from various complications, with the most common being diabetic cardiomyopathy. However, the detection rate of diabetic cardiomyopathy is low in clinical practice, and targeted treatment is lacking. Recently, a large number of studies have confirmed that myocardial cell death in diabetic cardiomyopathy involves pyroptosis, apoptosis, necrosis, ferroptosis, necroptosis, cuproptosis, cellular burial, and other processes. Most importantly, numerous animal studies have shown that the onset and progression of diabetic cardiomyopathy can be mitigated by inhibiting these regulatory cell death processes, such as by utilizing inhibitors, chelators, or genetic manipulation. Therefore, we review the role of ferroptosis, necroptosis, and cuproptosis, three novel forms of cell death in diabetic cardiomyopathy, searching for possible targets, and analyzing the corresponding therapeutic approaches to these targets.

Ferroptosis, necroptosis and cuproptosis: Novel forms of regulated cell death in diabetic cardiomyopathy

Diabetes is a common chronic metabolic disease, and its incidence continues to increase year after year. Diabetic patients mainly die from various complications, with the most common being diabetic cardiomyopathy. However, the detection rate of diabetic cardiomyopathy is low in clinical practice, and targeted treatment is lacking. Recently, a large number of studies have confirmed that myocardial cell death in diabetic cardiomyopathy involves pyroptosis, apoptosis, necrosis, ferroptosis, necroptosis, cuproptosis, cellular burial, and other processes. Most importantly, numerous animal studies have shown that the onset and progression of diabetic cardiomyopathy can be mitigated by inhibiting these regulatory cell death processes, such as by utilizing inhibitors, chelators, or genetic manipulation. Therefore, we review the role of ferroptosis, necroptosis, and cuproptosis, three novel forms of cell death in diabetic cardiomyopathy, searching for possible targets, and analyzing the corresponding therapeutic approaches to these targets.

CircRNA DICAR as a novel endogenous regulator for diabetic cardiomyopathy and diabetic pyroptosis of cardiomyocytes

In this study, we identified that a conserved circular RNA (circRNA) DICAR, which was downregulated in diabetic mouse hearts. DICAR had an inhibitory effect on diabetic cardiomyopathy (DCM), as the spontaneous cardiac dysfunction, cardiac cell hypertrophy, and cardiac fibrosis occurred in DICAR deficiency (DICAR^+/-) mice, whereas the DCM was alleviated in DICAR-overexpressed DICAR^Tg mice. At the cellular level, we found that overexpression of DICAR inhibited, but knockdown of DICAR enhanced the diabetic cardiomyocyte pyroptosis. At the molecular level, we identified that DICAR-VCP-Med12 degradation could be the underlying molecular mechanism in DICAR-mediated effects. The synthesized DICAR junction part (DICAR-JP) exhibited a similar effect to the entire DICAR. In addition, the expression of DICAR in circulating blood cells and plasma from diabetic patients was lower than that from health controls, which was consistent with the decreased DICAR expression in diabetic hearts. DICAR and the synthesized DICAR-JP may be drug candidates for DCM.

Up-regulating microRNA-214-3p relieves hypoxic-ischemic brain damage through inhibiting TXNIP expression

A list of microRNAs (miRs) has been referred to involve in the development of hypoxic-ischemic brain damage (HIBD). Based on that, we probed the concrete role of miR-214-3p regulating thioredoxin-interacting protein (TXNIP) in the illness. A neonatal HIBD mouse model was established using the Rice-Vannucci method, followed by measurements of miR-214-3p and TXNIP levels in brain tissues. After modeling, mice were given brain injection of the compounds that could alter miR-214-3p and TXNIP expression. Afterward, neurological function, neuronal inflammation, neuronal apoptosis, neuron morphology, and the number of Nissl body were assessed in HIBD mice. The binding of miR-214-3p to TXNIP was analyzed. Lower miR-214-3p and higher TXNIP were analyzed in brain tissues of mice with HIBD. Up-regulating miR-214-3p or depleting TXNIP improved neurological function, reduced neuronal inflammation and neuronal apoptosis, attenuated morphological damage of neurons, and increased the number of Nissl bodies in mice with HIBD. TXNIP was targeted by miR-214-3p and overexpressing TXNIP reversed the therapeutic effect of miR-214-3p on HIBD mice. It is noted that promotion of miR-214-3p relieves HIBD in mice through inhibiting TXNIP expression.

A landscape of Long non-coding RNAs reveals the leading transcriptome alterations in murine aorta during aging

Considerable studies have given convincing evidence of a forefront position for vascular aging in preventing cardiovascular disease. Various functions of Long non-coding RNAs (lncRNAs) are becoming increasingly distinct in aging-related diseases. This study aims at a better insight into the expression profile and mechanisms of lncRNAs in vascular senescence. High-throughput sequencing was used to detect the differential expression (DE) of lncRNAs and mRNAs in the aorta of 96 W and 8 W-old mice, while 1423 lncRNAs and 80 mRNAs were differentially expressed. By performing GO and KEGG enrichment analysis, we found that DE lncRNAs were mainly involved in purine metabolism and cGMP-PKG signaling pathways. In addition, a co-expression functional network of DE lncRNAs and DE mRNAs was constructed, and ENSMUST00000218874 could interact with 41 DE mRNAs, suggesting that it may play an essential role in vascular senescence. This study reveals DE lncRNAs in naturally aging vascular, which may provide new ideas and targets for aging-related cardiovascular diseases.

A pyroptosis-related lncRNA signature in bladder cancer

PURPOSE

Pyroptosis, a type of programmed cell death, is implicated in the tumorigenesis, development and migration of cancer, which can be regulated by long non-coding RNAs (lncRNAs). Our research aimed to investigate the prognostic role of pyroptosis-related lncRNAs and the relationship to the tumor immune microenvironment through bioinformatics analysis.

METHODS

The clinical and RNA-sequencing data of bladder cancer patients were downloaded from The Cancer Genome Atlas (TCGA). And 412 bladder cancer subjects with clinical information were divided into training and testing cohort. And 52 reported pyroptosis-related genes were used to screen pyroptosis-related lncRNAs. A pyroptosis-related lncRNA signature was constructed based on Cox regression analyses.

RESULTS

A 9-pyroptosis-related-lncRNA signature was identified to separate patients with bladder cancer into two groups. The prognosis of bladder cancer patients in the high-risk group was significantly inferior compared with those in the low-risk group. Risk scores were validated to develop an independent prognostic indicator based on multivariate Cox regression analysis. Receiver operating characteristic curve (ROC) analysis examined the signature on overall survival. The area under time-dependent ROC curve (AUC) at 1-, 3, and 5-years measured 0.747, 0.783, and 0.768, respectively. Analysis of the immune landscape and PD-L1 expression showed that PD-L1 is upregulated in the high-risk group. The immunocyte subtypes of the two groups were different.

CONCLUSION

A novel pyroptosis-related lncRNA signature was identified with prognostic value for bladder cancer patients. Pyroptosis-related lncRNAs have a potential role in cancer immunology and may serve as prognostic or therapeutic targets.

The Function and Therapeutic Potential of lncRNAs in Cardiac Fibrosis

Cardiac fibrosis remains an unresolved problem in cardiovascular diseases. Fibrosis of the myocardium plays a key role in the clinical outcomes of patients with heart injuries. Moderate fibrosis is favorable for cardiac structure maintaining and contractile force transmission, whereas adverse fibrosis generally progresses to ventricular remodeling and cardiac systolic or diastolic dysfunction. The molecular mechanisms involved in these processes are multifactorial and complex. Several molecular mechanisms, such as TGF-β signaling pathway, extracellular matrix (ECM) synthesis and degradation, and non-coding RNAs, positively or negatively regulate myocardial fibrosis. Long noncoding RNAs (lncRNAs) have emerged as significant mediators in gene regulation in cardiovascular diseases. Recent studies have demonstrated that lncRNAs are crucial in genetic programming and gene expression during myocardial fibrosis. We summarize the function of lncRNAs in cardiac fibrosis and their contributions to miRNA expression, TGF-β signaling, and ECMs synthesis, with a particular attention on the exosome-derived lncRNAs in the regulation of adverse fibrosis as well as the mode of action of lncRNAs secreted into exosomes. We also discuss how the current knowledge on lncRNAs can be applied to develop novel therapeutic strategies to prevent or reverse cardiac fibrosis.

Suppression of Chronic Unpredictable Stress-Persuaded Increased Monoamine Oxidase Activity by Taurine Promotes Significant Neuroprotection in Zebrafish Brain

Neuropsychiatric upshots following chronic exposure to unpredictable adverse stressors have been well documented in the literature. Considering the significant impact of chronic unpredictable stress (CUS), the literature is elusive regarding the neuroprotective efficacy of taurine against CUS-induced oxidative stress and chromatin condensation in the zebrafish brain. In this study, to ameliorate CUS-persuaded neurological outcomes, waterborne treatment of taurine as a prophylactic intervention was undertaken. Further, our approach also focused on the gross neurobehavioral response of zebrafish, oxidative stress indices and neuromorphology of the zebrafish brain following CUS exposure with taurine treatment. Because taurine provides significant neuroprotection against oxidative insult, the cytosolic level of monoamine oxidase (MAO) in the zebrafish brain following CUS exposure is worth investigating. Further, as heightened MAO activity is associated with augmented oxidative and chromatin condensation, the focus of this study was on whether taurine provides neuroprotection by downregulating MAO levels in the brain. Our findings show that CUS-persuaded altered neurobehavioral response was significantly rescued by taurine. Moreover, our findings firmly support the hypothesis that taurine acts as a radical neuroprotector by restoring glutathione biosynthesis in the zebrafish brain subsequent to CUS exposure. Additionally, the rising level of brain MAO following chronic exposure to CUS is ameliorated by taurine treatment. These findings strongly advocate the role of taurine as a natural MAO inhibitor through the neuroprotection it provides against CUS-instigated oxidative stress in zebrafish. However, the fundamental neuroprotective mechanism of such natural compounds needs to be elucidated to determine their neuroprotective efficacy against stress regimens.

Targeting epigenetics in diabetic cardiomyopathy: Therapeutic potential of flavonoids

The pathophysiological mechanisms of diabetic cardiomyopathy have been extensively studied, but there is still a lack of effective prevention and treatment methods. The ability of flavonoids to protect the heart from diabetic cardiomyopathy has been extensively described. In recent years, epigenetics has received increasing attention from scholars in exploring the etiology and treatment of diabetes and its complications. DNA methylation, histone modifications and non-coding RNAs play key functions in the development, maintenance and progression of diabetic cardiomyopathy. Hence, prevention or reversal of the epigenetic alterations that have occurred during the development of diabetic cardiomyopathy may alleviate the personal and social burden of the disease. Flavonoids can be used as natural epigenetic modulators in alternative therapies for diabetic cardiomyopathy. In this review, we discuss the epigenetic effects of different flavonoid subtypes in diabetic cardiomyopathy and summarize the evidence from preclinical and clinical studies that already exist. However, limited research is available on the potential beneficial effects of flavonoids on the epigenetics of diabetic cardiomyopathy. In the future, clinical trials in which different flavonoids exert their antidiabetic and cardioprotective effects through various epigenetic mechanisms should be further explored.

Ginseng glycoprotein and ginsenoside facilitate anti UV damage effects in diabetic rats

Diabetes mellitus combined with ultraviolet (UV) radiation damage not only brings great mental stress to patients, but also seriously impairs their quality of life. A UV-irradiated diabetic rat trauma skin model was established by us to investigate the effects and possible mechanisms of ginsenoside and glycoprotein on skin trauma repair in UV-irradiated diabetic rats. In the study, ginsenosides and ginseng glycoproteins were extracted from different parts of ginseng roots. It found that it's easier to prepare saponins in ginseng bark and proteins in ginseng core in large quantities. Since glycoprotein-like metabolites are relatively novel ginseng extracts, specifically characterized its structures. It was verified that the ginseng glycoproteins are not toxic to HaCaT cells and can significantly increase the survival of HaCaT cells after UV damage at the in vitro cellular level. Experiments in vivo were conducted to evaluate the therapeutic effects of ginsenoside and ginseng glycoprotein in a rat model of diabetes mellitus combined with UV irradiation injury. Histopathological changes on rat skin after treatment with ginsenoside and ginseng glycoprotein were evaluated by hematoxylin and eosin (H&E) staining and aldehyde fuchsine staining. The expression levels of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), matrix metalloproteinases (MMPs), hydroxyproline (HYP), interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) were measured. The results indicate that both ginsenoside and ginseng glycoprotein could improve skin damage and ulcers caused by diabetes combined with UV irradiation and could alleviate a range of skin damage caused by the combination of diabetes and UV irradiation, including peroxidation and collagen fiber loss. Ginsenoside and ginseng glycoproteins can be considered as natural product candidates for the development of new drugs to treat diabetes combined with UV irradiation-induced skin damage.

Garlic (Allium sativum L.) in diabetes and its complications: Recent advances in mechanisms of action

Diabetes mellitus (DM) is a metabolic disease characterized by chronic hyperglycemia and impaired islet secretion that places a heavy burden on the global health care system due to its high incidence rate, long disease course and many complications. Fortunately, garlic (Allium sativum L.), a well-known medicinal plant and functional food without the toxicity and side effects of conventional drugs, has shown positive effects in the treatment of diabetes and its complications. With interdisciplinary development and in-depth exploration, we offer a clear and comprehensive summary of the research from the past ten years, focusing on the mechanisms and development processes of garlic in the treatment of diabetes and its complications, aiming to provide a new perspective for the treatment of diabetes and promote the efficient development of this field.

Unveiling the Vital Role of Long Non-Coding RNAs in Cardiac Oxidative Stress, Cell Death, and Fibrosis in Diabetic Cardiomyopathy

Diabetes mellitus is a burdensome public health problem. Diabetic cardiomyopathy (DCM) is a major cause of mortality and morbidity in diabetes patients. The pathogenesis of DCM is multifactorial and involves metabolic abnormalities, the accumulation of advanced glycation end products, myocardial cell death, oxidative stress, inflammation, microangiopathy, and cardiac fibrosis. Evidence suggests that various types of cardiomyocyte death act simultaneously as terminal pathways in DCM. Long non-coding RNAs (lncRNAs) are a class of RNA transcripts with lengths greater than 200 nucleotides and no apparent coding potential. Emerging studies have shown the critical role of lncRNAs in the pathogenesis of DCM, along with the development of molecular biology technologies. Therefore, we summarize specific lncRNAs that mainly regulate multiple modes of cardiomyopathy death, oxidative stress, and cardiac fibrosis and provide valuable insights into diagnostic and therapeutic biomarkers and strategies for DCM.

MTHFR epigenetic derepression protects against diabetes cardiac fibrosis

BACKGROUND

Diabetes cardiac fibrosis is associated with altered DNA methylation of fibrogenic genes; however, the underlying mechanisms remain unclear.

OBJECTIVES

In this study, we investigate the critical role of DNA methylation aberration-associated suppression of MTHFR in diabetes cardiac fibrosis, and the protective effects of folate on diabetes cardiac fibrosis, using cultured cells, animal models, and clinical samples.

METHODS AND RESULTS

Herein, we report that DNA methylation repression of MTHFR, critically involved in diabetes cardiac fibrosis, mediates the significant protective effects of folate in a mouse model of diabetes cardiac fibrosis induced by STZ. Heart MTHFR expression was markedly suppressed in diabetes cardiac fibrosis patients and mice, accompanied by increased DNMT3A and MTHFR promoter methylation. Knockdown of DNMT3A demethylated MTHFR promoter, recovered the MTHFR loss, and alleviated the diabetes cardiac fibrosis pathology and cardiac fibroblasts pyroptosis. Mechanistically, DNMT3A epigenetically repressed MTHFR expression via methylation of the promoter. Interestingly, folate supplementation can rescue the effect of MTHFR loss in diabetes cardiac fibrosis, suggesting that inactivation of MTHFR through epigenetics is a critical mediator of diabetes cardiac fibrosis.

CONCLUSIONS

The current study identifies that MTHFR repression due to aberrant DNMT3A elevation and subsequent MTHFR promoter hypermethylation is likely an important epigenetic feature of diabetes cardiac fibrosis, and folate supplementation protects against diabetes cardiac fibrosis.

LncRNA Airn alleviates diabetic cardiac fibrosis by inhibiting activation of cardiac fibroblasts via a m6A-IMP2-p53 axis

BACKGROUND

Cardiac fibrosis is a leading cause of cardiac dysfunction in patients with diabetes. However, the underlying mechanisms of cardiac fibrosis remain unclear. This study aimed to investigate the role of the long non-coding RNA (LncRNA) Airn in the pathogenesis of cardiac fibrosis in diabetic cardiomyopathy (DCM) and its underlying mechanism.

METHODS

Diabetes mellitus (DM) was induced in mice by streptozotocin injection. An intramyocardial adeno-associated virus (AAV) was used to manipulate Airn expression. The functional significance and underlying mechanisms in DCM fibrosis were investigated both in vitro and in vivo.

RESULTS

Diabetic hearts showed a significant impairment in cardiac function, accompanied by obviously increased cardiac fibrosis. Interestingly, lncRNA Airn expression was significantly decreased in both diabetic hearts and high glucose (HG)-treated cardiac fibroblasts (CFs). AAV-mediated Airn reconstitution prevented cardiac fibrosis and the development of DCM, while Airn knockdown induced cardiac fibrosis phenotyping DCM. As in vitro, Airn reversed HG-induced fibroblast-myofibroblast transition, aberrant CFs proliferation and section of collagen I. In contrast, Airn knockdown mimicked a HG-induced CFs phenotype. Mechanistically, we identified that Airn exerts anti-fibrotic effects by directly binding to insulin-like growth factor 2 mRNA-binding protein 2 (IMP2) and further prevents its ubiquitination-dependent degradation. Moreover, we revealed that Airn/IMP2 protected p53 mRNA from degradation in m6A manner, leading to CF cell cycle arrest and reduced cardiac fibrosis. As a result, ablation of p53 blunted the inhibitory effects of Airn on fibroblast activation and cardiac fibrosis.

CONCLUSIONS

Our study demonstrated for the first time that Airn prevented the development of cardiac fibrosis in diabetic heart via IMP2-p53 axis in an m6A dependent manner. LncRNA Airn could be a promising therapeutic target for cardiac fibrosis in DCM.

LncRNA KCNQ1OT1: Molecular mechanisms and pathogenic roles in human diseases

Long non-coding RNAs (lncRNAs) exhibit a length more than 200 nucleotides and they are characterized by non-coding RNAs (ncRNA) not encoded into proteins. Over the past few years, the role and development of lncRNAs have aroused the rising attention of researchers. To be specific, KCNQ1OT1, the KCNQ1 opposite strand/antisense transcript 1, is clearly classified as a regulatory ncRNA. KCNQ1OT1 is capable of interacting with miRNAs, RNAs and proteins, thereby affecting gene expression and various cell functions (e.g., cell proliferation, migration, epithelial-mesenchymal transition (EMT), apoptosis, viability, autophagy and inflammation). KCNQ1OT1 is dysregulated in a wide range of human diseases (e.g., cardiovascular disease, cancer, diabetes, osteoarthritis, osteoporosis and cataract), and it is speculated to act as a therapeutic target for treating various human diseases. On the whole, this review aims to explore the biological functions, underlying mechanisms and pathogenic roles of KCNQ1OT1 in human diseases.

Silencing lncRNA KCNQ1OT1 reduced hepatic ischemia reperfusion injury-induced pyroptosis by regulating miR-142a-3p/HMGB1 axis

BACKGROUND

Based on pre-existing evidence, KCNQ1OT1 has been pointed out to be closely related to myocardial and cerebral ischemia reperfusion injury diseases. Herein, the objective of our study is to probe into the potential function as well as the underlying mechanism of KCNQ1OT1 on hepatic ischemia reperfusion injury (HIRI).

METHODS

Using C57BL/6 J mice and primary mouse hepatocytes were conducted to establish HIRI model in vivo and in vitro. Cell viability was examined using CCK-8 assay and EdU assay. Flow cytometric analysis was performed to evaluate the pyroptosis. Dual-luciferase reporter assay was employed to verify the interaction relationships. qRT-PCR and Western blot were adopted to analyze the mRNA and protein level. Histopathological alteration of liver tissue was evaluated by HE staining. Immunohistochemistry (IHC) was performed to measure NLRP3 and caspase 1.

RESULTS

Our data revealed that KCNQ1OT1 expression was ascending in hepatic tissue of HIRI mouse. Moreover, deprivation of KCNQ1OT1 mitigated I/R-induced hepatic injury and pyroptosis in vivo. Further experiments demonstrated that silencing KCNQ1OT1 promoted proliferation and inhibited pyroptosis in hypoxia/reoxygenation (H/R)-induced primary mouse hepatocytes. Mechanistically, KCNQ1OT1 functioned as a competing endogenous RNA which sponged miR-142a-3p, therefore promoted HMGB1 expression to activate TLR4/NF-κB signaling pathway in HIRI.

CONCLUSION

LncRNA KCNQ1OT1 elevated HMGB1 expression through binding to miR-142a-3p, thereby promoting pyroptosis in HIRI.

Puerarin-V Improve Mitochondrial Respiration and Cardiac Function in a Rat Model of Diabetic Cardiomyopathy via Inhibiting Pyroptosis Pathway through P2X7 Receptors

There is a new form of puerarin, puerarin-V, that has recently been developed, and it is unclear whether puerarin-V has a cardioprotective effect on diabetic cardiomyopathy (DCM). Here, we determined whether puerarin-V had any beneficial influence on the pathophysiology of DCM and explored its possible mechanisms. By injecting 30 mg/kg of STZ intraperitoneally, diabetes was induced in rats. After a week of stability, the rats were injected subcutaneously with ISO (5 mg/kg). We randomly assigned the rats to eight groups: (1) control; (2) model; (3) metformin; (4-6) puerarin-V at different doses; (7) puerarin (API); (8) puerarin injection. DCM rats were found to have severe cardiac insufficiency (arrythmia, decreased LVdP/dt, and increased E/A ratio). In addition, cardiac injury biomarkers (cTn-T, NT-proBNP, AST, LDH, and CK-MB), inflammatory cytokines (IL-1β, IL-18, IL-6, and TNF-α), and oxidative damage markers (MDA, SOD and GSH) were markedly increased. Treatment with puerarin-V positively adjusts these parameters mentioned above by improving cardiac function and mitochondrial respiration, suppressing myocardial inflammation, and maintaining the structural integrity of the cardiac muscle. Moreover, treatment with puerarin-V inhibits the P2X7 receptor-mediated pyroptosis pathway that was upregulated in diabetic hearts. Given these results, the current study lends credence to the idea that puerarin-V can reduce myocardial damage in DCM rats. Furthermore, it was found that the effect of puerarin-V in diabetic cardiomyopathy is better than the API, the puerarin injection, and metformin. Collectively, our research provides a new therapeutic option for the treatment of DCM in clinic.

Research status and trends of the diabetic cardiomyopathy in the past 10 years (2012–2021): A bibliometric analysis

Background

Diabetic cardiomyopathy is one of the most life-threatening diabetic complications. However, the previous studies only discuss a particular aspect or characteristic of DCM, the current state and trends were explored by limited research. We aimed to perform a systemically bibliometric study of DCM research progress status in the past decade, visualize the internal conceptual structure and potential associations, and further explore the prospective study trends.

Methods

Articles related to DCM published from January 2012 to December 2021 were collected in the Web of Science core collection (WoSCC) database on June 24, 2022. We exported all bibliographic records, including titles, abstracts, keywords, authorship, institutions, addresses, publishing sources, references, citation times, and year of publication. In addition, the journal Impact Factor and Hirsch index were obtained from the Journal Citation Report. We conducted the data screening, statistical analysis, and visualization via the Bibliometrix R package. VOS viewer software was employed to generate the collaboration network map among countries and institutions for better performance in visualization.

Results

In total, 1,887 original research articles from 2012 to 2021 were identified. The number of annual publications rapidly increased from 107 to 278, and a drastic increase in citation times was observed in 2017–2019. As for global contributions, the United States was the most influential country with the highest international collaboration, while China was the most productive country. Professor Cai Lu was the most prolific author. Shandong University published the most articles. Cardiovascular Diabetology journal released the most DCM-related articles. “Metabolic Stress-induced Activation of FoxO1 Triggers Diabetic Cardiomyopathy in Mice” Battiprolu PK et al., J Clin Invest, 2012. was the most top-cited article regarding local citations. The top three keywords in terms of frequency were apoptosis, oxidative stress, and fibrosis. The analysis of future topic trends indicated that “Forkhead box protein O1,” “Heart failure with preserved ejection fraction,” “Dapagliflozin,” “Thioredoxin,” “Mitochondria dysfunction,” “Glucose,” “Pyroptosis,” “Cardiac fibroblast” and “Long non-coding RNA” could be promising hotspots.

Conclusion

This study provides meaningful insights into DCM, which is expected to assist cardiologists and endocrinologists in exploring frontiers and future research directions in the domain through a refined and concise summary.

Glycation-Associated Diabetic Nephropathy and the Role of Long Noncoding RNAs

The glycation of various biomolecules is the root cause of many pathological conditions associated with diabetic nephropathy and end-stage kidney disease. Glycation imbalances metabolism and increases renal cell injury. Numerous therapeutic measures have narrowed down the adverse effects of endogenous glycation, but efficient and potent measures are miles away. Recent advances in the identification and characterization of noncoding RNAs, especially the long noncoding RNAs (lncRNAs), have opened a mammon of new biology to explore the mitigations for glycation-associated diabetic nephropathy. Furthermore, tissue-specific distribution and condition-specific expression make lncRNA a promising key for second-generation therapeutic interventions. Though the techniques to identify and exemplify noncoding RNAs are rapidly evolving, the lncRNA study encounters multiple methodological constraints. This review will discuss lncRNAs and their possible involvement in glycation and advanced glycation end products (AGEs) signaling pathways. We further highlight the possible approaches for lncRNA-based therapeutics and their working mechanism for perturbing glycation and conclude our review with lncRNAs biology-related future opportunities.

LncRNA KCNQ1OT1 predicts further cerebral events in patients with transient ischemic attack

Transient ischemic attack (TIA) poses a great threat of cerebrovascular diseases to a large number of patients, despite its reversible neurological dysfunction. Long non-coding RNAs (lncRNAs) have been proven to play critical roles in the pathophysiological development of cerebrovascular events. Exploring the function of lncRNAs in modulating TIA prognosis would help to develop individualized therapeutics. A total of 231 participants with the first onset of TIA were recruited in the study, including 65 subsequent stroke patients. The expression of lncRNA potassium voltage-gated channel subfamily Q member 1 opposite strand 1 (KCNQ1OT1) was upregulated in patients with recurrent ischemic events after TIA. Additionally, KCNQ1OT1 could be regarded as an independent predictor for subsequent ischemic stroke. The optimal diagnostic value was determined at 1.29 with a sensitivity of 63% and a specificity of 72%. Fewer patients would survive from further ischemic stroke with their KCNQ1OT1 level over 1.29. Furthermore, the expression of KCNQ1OT1 was elevated with a growing serum high-sensitivity C-reactive protein (hs-CRP) level. KCNQ1OT1 might be involved in the regulation of early inflammatory response during recurrence of TIA.

Antisense Transcription in Plants: A Systematic Review and an Update on cis-NATs of Sugarcane

Initially, natural antisense transcripts (NATs, natRNAs, or asRNAs) were considered repressors; however, their functions in gene regulation are diverse. Positive, negative, or neutral correlations to the cognate gene expression have been noted. Although the first studies were published about 50 years ago, there is still much to be investigated regarding antisense transcripts in plants. A systematic review of scientific publications available in the Web of Science databases was conducted to contextualize how the studying of antisense transcripts has been addressed. Studies were classified considering three categories: “Natural antisense” (208), artificial antisense used in “Genetic Engineering” (797), or “Natural antisense and Genetic Engineering”-related publications (96). A similar string was used for a systematic search in the NCBI Gene database. Of the 1132 antisense sequences found for plants, only 0.8% were cited in PubMed and had antisense information confirmed. This value was the lowest when compared to fungi (2.9%), bacteria (2.3%), and mice (54.1%). Finally, we present an update for the cis-NATs identified in Saccharum spp. Of the 1413 antisense transcripts found in different experiments, 25 showed concordant expressions, 22 were discordant, 1264 did not correlate with the cognate genes, and 102 presented variable results depending on the experiment.

Targeting Pyroptosis: New Insights into the Treatment of Diabetic Microvascular Complications

Pyroptosis is an inflammatory form of programmed cell death that is dependent on inflammatory caspases, leading to the cleavage of gasdermin D (GSDMD) and increased secretion of interleukin (IL)-1β and IL-18. Recent studies have reported that hyperglycemia-induced cellular stress stimulates pyroptosis, and different signaling pathways have been shown to play crucial roles in regulating pyroptosis. This review summarized and discussed the molecular mechanisms, regulation, and cellular effects of pyroptosis in diabetic microvascular complications, such as diabetic nephropathy, diabetic retinopathy, and diabetic cardiomyopathy. In addition, this review aimed to provide new insights into identifying better treatments for diabetic microvascular complications.

NLRP3 Inflammasome/Pyroptosis: A Key Driving Force in Diabetic Cardiomyopathy

Diabetic cardiomyopathy (DCM), a serious diabetic complication, is a kind of low-grade inflammatory cardiovascular disorder. Due to the high risk of morbidity and mortality, DCM has demanded the attention of medical researchers worldwide. The pathophysiological nature of DCM is intricate, and the genesis and development of which are a consequence of the coaction of many factors. However, the exact pathogenesis mechanism of DCM remains unclear. Pyroptosis is a newly identified programmed cell death (PCD) that is directly related to gasdermin D(GSDMD). It is characterized by pore formation on the cell plasma membrane, the release of inflammatory mediators, and cell lysis. The initiation of pyroptosis is closely correlated with NOD-like receptor 3 (NLRP3) activation, which activates caspase-1 and promotes the cleaving of GSDMD. In addition to adjusting the host’s immune defense, NLRP3 inflammasome/pyroptosis plays a critical role in controlling the systemic inflammatory response. Recent evidence has indicated that NLRP3 inflammasome/pyroptosis has a strong link with DCM. Targeting the activation of NLRP3 inflammasome or pyroptosis may be a hopeful therapeutic strategy for DCM. The focus of this review is to summarize the relevant mechanisms of pyroptosis and the relative contributions in DCM, highlighting the potential therapeutic targets in this field.

The Role of NLRP3 Inflammasome in Diabetic Cardiomyopathy and Its Therapeutic Implications

Diabetic cardiomyopathy (DCM) is a serious complication of diabetes mellitus (DM). However, the precise molecular mechanisms remain largely unclear, and it is still a challenging disease to diagnose and treat. The nucleotide-binding oligomerization domain and leucine-rich repeat pyrin 3 domain (NLRP3) inflammasome is a critical part of the innate immune system in the host to defend against endogenous danger and pathogenic microbial infections. Dysregulated NLRP3 inflammasome activation results in the overproduction of cytokines, primarily IL-1β and IL-18, and eventually, inflammatory cell death-pyroptosis. A series of studies have indicated that NLRP3 inflammasome activation participates in the development of DCM, and that corresponding interventions could mitigate disease progression. Accordingly, this narrative review is aimed at briefly summarizing the cell-specific role of the NLRP3 inflammasome in DCM and provides novel insights into developing DCM therapeutic strategies targeting the NLRP3 inflammasome.

The role of pyroptosis and its crosstalk with immune therapy in breast cancer

Pyroptosis is a brand-new category of programmed cell death (PCD) that is brought on by multitudinous inflammasomes, which can recognize several stimuli to pilot the cleavage of and activate inflammatory cytokines like IL-18 and IL-1β is believed to have dual effects on the development of multiple cancers including breast cancer. However, pyroptosis has different effects on cancers depending on the type of tissues and their distinct heredity. Recently, the association between pyroptosis and breast cancer has received more and more attention, and it is thought that inducing pyroptosis could be used as a cancer treatment option. In addition, a great deal of evidence accumulating over the past decades has evinced the crosstalk between pyroptosis and tumor immunological therapy. Thus, a comprehensive summary combining the function of pyroptosis in breast cancer and antitumor immunity is imperative. We portray the prevalent knowledge of the multidimensional roles of pyroptosis in cancer and summarize the pyroptosis in breast cancer principally. Moreover, we elucidate the influence of inflammasomes and pyroptosis-produced cytokines on the tumor microenvironment (TME) of breast cancer. Taken together, we aim to provide a clue to harness pyroptosis rationally and apply it to augment immunotherapy efficiency for breast cancer.

Therapeutic Implications of Targeting Pyroptosis in Cardiac-related Etiology of Heart Failure

Heart failure remains a considerable clinical and public health problem, it is the dominant cause of death from cardiovascular diseases, besides, cardiovascular diseases are one of the leading causes of death worldwide. The survival of patients with heart failure continues to be low with 45-60% reported deaths within five years. Apoptosis, necrosis, autophagy, and pyroptosis mediate cardiac cell death. Acute cell death is the hallmark pathogenesis of heart failure and other cardiac pathologies. Inhibition of pyroptosis, autophagy, apoptosis, or necrosis reduces cardiac damage and improves cardiac function in cardiovascular diseases. Pyroptosis is a form of inflammatory deliberate cell death that is characterized by the activation of inflammasomes such as NOD-like receptors (NLR), absent in melanoma 2 (AIM2), interferon-inducible protein 16 (IFI-16), and their downstream effector cytokines: Interleukin IL-1β and IL-18 leading to cell death. Recent studies have shown that pyroptosis is also the dominant cell death process in cardiomyocytes, cardiac fibroblasts, endothelial cells, and immune cells. It plays a crucial role in the pathogenesis of cardiac diseases that contribute to heart failure. This review intends to summarize the therapeutic implications targeting pyroptosis in the main cardiac pathologies preceding heart failure.

MLKL-mediated necroptosis is a target for cardiac protection in mouse models of type-1 diabetes

Background

Cardiomyocyte death contributes to cardiac pathology of diabetes. Studies have shown that the RIPK3/MLKL necroptosis signaling is activated in diabetic hearts. Deletion of RIPK3 was reported to attenuate myocardial injury and heart dysfunction in streptozocin (STZ)-induced diabetic mice, suggesting a potential role of necroptosis in diabetic cardiomyopathy. This study characterized cardiomyocyte necroptosis in diabetic hearts and investigated whether MLKL-mediated necroptosis is a target for cardiac protection in diabetes.

Methods

Type 1 diabetes was induced in RIPK3 knockout, MLKL knockout and wild-type mice. Akita Type-1 diabetic mice were injected with shRNA for MLKL. Myocardial function was assessed by echocardiography. Immuno-histological analyses determined cardiomyocyte death and fibrosis in the heart. Cultured adult mouse cardiomyocytes were incubated with high glucose in the presence of various drugs. Cell death and phosphorylation of RIPK3 and MLKL were analysed.

Results

We showed that the levels of phosphorylated RIPK3 and MLKL were higher in high glucose-stimulated cardiomyocytes and hearts of STZ-induced type-1 diabetic mice, akita mice and type-1 diabetic monkeys when compared to non-diabetic controls. Inhibition of RIPK3 by its pharmacological inhibitor or gene deletion, or MLKL deletion prevented high glucose-induced MLKL phosphorylation and attenuated necroptosis in cardiomyocytes. In STZ-induced type-1 diabetic mice, cardiomyocyte necroptosis was present along with elevated cardiac troponin I in serum and MLKL oligomerization, and co-localized with phosphorylated MLKL. Deletion of RIPK3 or MLKL prevented MLKL phosphorylation and cardiac necroptosis, attenuated serum cardiac troponin I levels, reduced myocardial collagen deposition and improved myocardial function in STZ-injected mice. Additionally, shRNA-mediated down-regulation of MLKL reduced cardiomyocyte necroptosis in akita mice. Interestingly, incubation with anti-diabetic drugs (empagliflozin and metformin) prevented phosphorylation of RIPK3 and MLKL, and reduced cell death in high glucose-induced cardiomyocytes.

Conclusions

We have provided evidence that cardiomyocyte necroptosis is present in diabetic hearts and that MLKL-mediated cardiomyocyte necroptosis contributes to diabetic cardiomyopathy. These findings highlight MLKL-mediated necroptosis as a target for cardiac protection in diabetes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01602-9.

Gut microbiota: A new therapeutic target for diabetic cardiomyopathy

Diabetic cardiomyopathy seriously affects quality of life and even threatens life safety of patients. The pathogenesis of diabetic cardiomyopathy is complex and multifactorial, and it is widely accepted that its mechanisms include oxidative stress, inflammation, insulin resistance, apoptosis, and autophagy. Some studies have shown that gut microbiota plays an important role in cardiovascular diseases. Gut microbiota and its metabolites can affect the development of diabetic cardiomyopathy by regulating oxidative stress, inflammation, insulin resistance, apoptosis, and autophagy. Here, the mechanisms of gut microbiota and its metabolites resulting in diabetic cardiomyopathy are reviewed. Gut microbiota may be a new therapeutic target for diabetic cardiomyopathy.

Non-coding RNAs in necroptosis, pyroptosis, and ferroptosis in cardiovascular diseases

Accumulating evidence has proved that non-coding RNAs (ncRNAs) play a critical role in the genetic programming and gene regulation of cardiovascular diseases (CVDs). Cardiovascular disease morbidity and mortality are rising and have become a primary public health issue that requires immediate resolution through effective intervention. Numerous studies have revealed that new types of cell death, such as pyroptosis, necroptosis, and ferroptosis, play critical cellular roles in CVD progression. It is worth noting that ncRNAs are critical novel regulators of cardiovascular risk factors and cell functions by mediating pyroptosis, necroptosis, and ferroptosis. Thus, ncRNAs can be regarded as promising therapeutic targets for treating and diagnosing cardiovascular diseases. Recently, there has been a surge of interest in the mediation of ncRNAs on three types of cell death in regulating tissue homeostasis and pathophysiological conditions in CVDs. Although our understanding of ncRNAs remains in its infancy, the studies reviewed here may provide important new insights into how ncRNAs interact with CVDs. This review summarizes what is known about the functions of ncRNAs in modulating cell death-associated CVDs and their role in CVDs, as well as their current limitations and future prospects.

Non-coding RNAs: Important participants in cardiac fibrosis

Cardiac remodeling is a pathophysiological process activated by diverse cardiac stress, which impairs cardiac function and leads to adverse clinical outcome. This remodeling partly attributes to cardiac fibrosis, which is a result of differentiation of cardiac fibroblasts to myofibroblasts and the production of excessive extracellular matrix within the myocardium. Non-coding RNAs mainly include microRNAs and long non-coding RNAs. These non-coding RNAs have been proved to have a profound impact on biological behaviors of various cardiac cell types and play a pivotal role in the development of cardiac fibrosis. This review aims to summarize the role of microRNAs and long non-coding RNAs in cardiac fibrosis associated with pressure overload, ischemia, diabetes mellitus, aging, atrial fibrillation and heart transplantation, meanwhile shed light on the diagnostic and therapeutic potential of non-coding RNAs for cardiac fibrosis.

Current knowledge of pyroptosis in heart diseases

Pyroptosis is a form of pro-inflammatory, necrotic cell death mediated by proteins of the gasdermin family. Various heart diseases, including myocardial ischemia/reperfusion injury, myocardial infarction, and heart failure, involve cardiomyocyte and non-myocyte pyroptosis. Cardiomyocyte pyroptosis also causes the release of pro-inflammatory cytokines. Recent studies have confirmed that pyroptosis is predominantly triggered by both the canonical and non-canonical inflammasome pathways, which independently facilitate caspase-1 or caspase-11/4/5 activation and gasdermin D (GSDMD) cleavage. Cardiac fibroblast and myeloid cell pyroptosis also contributes to the pathogenesis and development of heart diseases. This review summarizes the recent studies on pyroptosis in heart diseases and discusses the associated therapeutic targets.

Spotlight on pyroptosis: role in pathogenesis and therapeutic potential of ocular diseases

Pyroptosis is a programmed cell death characterized by swift plasma membrane disruption and subsequent release of cellular contents and pro-inflammatory mediators (cytokines), including IL‐1β and IL‐18. It differs from other types of programmed cell death such as apoptosis, autophagy, necroptosis, ferroptosis, and NETosis in terms of its morphology and mechanism. As a recently discovered form of cell death, pyroptosis has been demonstrated to be involved in the progression of multiple diseases. Recent studies have also suggested that pyroptosis is linked to various ocular diseases. In this review, we systematically summarized and discussed recent scientific discoveries of the involvement of pyroptosis in common ocular diseases, including diabetic retinopathy, age-related macular degeneration, AIDS-related human cytomegalovirus retinitis, glaucoma, dry eye disease, keratitis, uveitis, and cataract. We also organized new and emerging evidence suggesting that pyroptosis signaling pathways may be potential therapeutic targets in ocular diseases, hoping to provide a summary of overall intervention strategies and relevant multi-dimensional evaluations for various ocular diseases, as well as offer valuable ideas for further research and development from the perspective of pyroptosis.

Silencing long noncoding RNA-CES1P1 suppresses glomerular endothelial cell inflammation in diabetic nephropathy

Diabetic nephropathy (DN) has become the main cause of end-stage renal disease worldwide. Inflammation is associated with the occurrence and development of DN, and long noncoding RNAs (lncRNAs) are involved in the regulation of inflammatory processes. This study aims to determine the role and mechanism of lncRNA-CES1P1 in DN.C57BL/6 mice and human umbilical vein endothelial cells (HUVECs) were used for this experimental study. In vivo experimental intraperitoneal injection of streptozotocin (STZ) to construct a diabetes mellitus (DM) model in C57BL/6 mice caused increased expression of lncRNA-CES1P1, decreased expression of miR-214-3p in kidney tissue, and produced renal inflammation and proteinuria. Exogenous knockdown of lncRNA-CES1P1 expression decreased renal inflammatory infiltration. In vitro experiments using high glucose (HG) stimulation of HUVECs cell revealed increased expression of lncRNA-CES1P1, decreased expression of miR-214-3p, and increased expression of the inflammatory factors IL-17, IκB, NF-κB, and IL-6. Luciferase reporter assays showed direct targets of miR-214-3p interaction with lncRNA-CES1P1 and IL-17. These results suggest that hyperglycemia represses miR-214-3p by inducing lncRNA-CES1P1, which promotes the expression of the inflammatory factors IL-17, IκB, NF-κB and IL-6 ultimately leading to the development of DN. Interfering with lncRNA-CES1P1 can reduce hyperglycemia-induced DN.

Melatonin Alleviates Hyperglycemia-Induced Cardiomyocyte Apoptosis via Regulation of Long Non-Coding RNA H19/miR-29c/MAPK Axis in Diabetic Cardiomyopathy

Recent studies revealed that non-coding RNAs (ncRNAs) play a crucial role in pathophysiological processes involved in diabetic cardiomyopathy (DCM) that contribute to heart failure. The present study was designed to further investigate the anti-apoptotic effect of melatonin on cardiomyocytes in diabetic conditions, and to elucidate the potential mechanisms associated with ncRNAs. In animal models, we induced diabetes in SD rats by single intraperitoneal injection of streptozotocin (STZ) solution (55 mg/kg) at 18:00 in the evening, after a week of adaptive feeding. Our results indicate that melatonin notably alleviated cardiac dysfunction and cardiomyocyte apoptosis. In the pathological situation, lncRNA H19 level increased, along with a concomitant decrease in miR-29c level. Meanwhile, melatonin significantly downregulated lncRNA H19 and upregulated miR-29c levels. In our in vitro experiments, we treated H9c2 cells with high-concentration glucose medium (33 mM) to simulate the state of diabetes. It was verified that positive modulation of miR-29c and inhibition of lncRNA H19, as well as mitogen-activated protein kinase (MAPK) pathways, distinctly attenuated apoptosis in high-glucose-treated H9c2 cells. A luciferase activity assay was conducted to evaluate the potential target sites of miR-29c on lncRNA H19 and MAPK13. LncRNA H19 silencing significantly downregulated the expression of miR-29c target gene MAPK13 by inducing miR-29c expression. Most importantly, our results show that melatonin alleviated apoptosis by inhibiting lncRNA H19/MAPK and increasing miR-29c level. Our results elucidate a novel protective mechanism of melatonin on diabetic cardiomyocyte apoptosis, which involved the regulation of lncRNA H19/miR-29c and MAPK pathways, providing a promising strategy for preventing DCM in diabetic patients.

Progress toward molecular therapy for diabetes mellitus: A focus on targeting inflammatory factors

Diabetes mellitus (DM) has been the most prevalent global metabolic disease, turning into a serious risk for human health. Several researches have recorded a role for inflammation and immunity in the pathogenesis of both in T1DM and in T2DM. Lots of chemical agents are available to control and to cure diabetic patients, which are not always sufficient for euglycemia maintenance and late stage diabetic complications avoidance. Therefore, newborn therapeutic methods to refine clinical outcomes in DM are required. Nucleic-acid-based therapy also known as gene expression level regulator within the target cells has been calculated to be promising in various diseases. Thus, pronounced attempts have been dedicated to develop new targeted molecular therapy aimed at improving insulin resistance in DM. This review mainly focuses on recent progress in DM molecular therapy and whether, has potential efficacy against inflammatory mediators involved in DM.

LncRNA KCNQ1OT1 promotes the apoptosis and inflammatory response of microglia by regulating the miR-589-5p/NPTN axis after spinal cord injury

Spinal cord injury (SCI) is a devastating traumatic condition accompanied with excessive inflammatory response and apoptosis of microglia. Long noncoding RNAs (lncRNAs) have been confirmed to be key regulators of cell inflammatory response. Nevertheless, the role of lncRNA KCNQ1OT1 in microglia apoptosis or inflammatory response after SCI remains to be explored. Our study focused on exploring the role and mechanism of KCNQ1OT1 in microglia after SCI. RT-qPCR showed that SCI induced the increase of KCNQ1OT1 level in mice spinal cord. Inhibition of KCNQ1OT1 suppressed the inflammatory response and apoptosis of microglia. In addition, KCNQ1OT1 was proved to bind with miR-589-5p, and NPTN was directly targeted by miR-589-5p. Furthermore, KCNQ1OT1 was negatively correlated with miR-589-5p and positively associated with NPTN. Rescue assays indicated that NPTN overexpression reversed the anti-inflammatory and anti-apoptosis effects of KCNQ1OT1 silencing. In summary, these data revealed that KCNQ1OT1 promoted inflammatory response and apoptosis of microglia by regulating the miR-589-5p/NPTN axis after SCI, which may offer a novel promising therapeutic target for SCI.

Mitochondrial damage and activation of the cytosolic DNA sensor cGAS-STING pathway lead to cardiac pyroptosis and hypertrophy in diabetic cardiomyopathy mice

Diabetic cardiomyopathy (DCM) is a serious cardiac complication of diabetes that currently lacks specific treatment. The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway has been suggested to contribute to the pathogenesis of cardiovascular diseases. However, whether cGAS-STING is involved in the development of DCM has not been established. Our study aimed to determine the role of cGAS-STING in the initiation of nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3 (NLRP3) inflammasome-induced cardiac pyroptosis and chronic inflammation during the pathogenesis of DCM. C57BL/6J mice were preinjected with adeno-associated virus 9 (AAV9) intravenously via the tail vein to specifically knock down myocardial STING. After four weeks, mice with myocardium-specific knockdown of STING received injections of streptozotocin (STZ; 50 mg/kg) and a high-fat diet to induce diabetes. Measurements included echocardiography, immunohistochemical analyses, wheat germ agglutinin (WGA) staining, and western blotting. Here, we showed that the cGAS-STING signaling pathway was activated in diabetic hearts, which was indicated by the increased phosphorylation of TANK-binding kinase 1 (TBK1) and interferon (IFN) regulatory factor 3 (IRF3), leading to the activation of the NLRP3 inflammasome in the hearts of diabetic mice and proinflammatory cytokine release into serum. Moreover, STING knockdown via adeno-associated virus-9 (AAV9) in diabetic mouse heart alleviated cardiac pyroptosis and the inflammatory response, prevented diabetes-induced hypertrophy, and restored cardiac function. Mechanistically, we showed that palmitic acid (PA)-induced lipotoxicity impairs mitochondrial homeostasis, producing excessive mitochondrial reactive oxygen species (mtROS), which results in oxidative damage to mitochondrial DNA (mtDNA) and its release into the cytoplasm while switching on cGAS-STING-mediated pyroptosis in cardiomyocytes, thereby worsening the progression of diabetic cardiomyopathy. Our study demonstrated that activation of the cGAS-STING pathway caused by mitochondrial oxidative damage and mtDNA escape induced by free fatty acids promoted pyroptosis and proinflammatory responses in cardiomyocytes in a NLRP3 inflammasome-dependent manner, thus promoting myocardial hypertrophy during the progression of DCM.

Curcumin improves the function of umbilical vein endothelial cells by inhibiting H2O2‑induced pyroptosis

Endothelial cell (EC) dysfunction is one of the initiating factors of atherosclerosis. EC dysfunction is primarily caused by oxidative damage and inflammation. As a classic non-specific antioxidant and anti-inflammatory drug, curcumin has been widely used in studies of lipid metabolism disorders. However, whether curcumin is able to alleviate H₂O₂-induced EC damage and its related mechanisms has remained to be elucidated. The present study confirmed the protective effects of curcumin on human umbilical vein endothelial cells (HUVECs). A HUVEC injury model was established using H₂O₂ and the optimal concentrations and time of curcumin to achieve therapeutic effects were explored. Curcumin was observed to inhibit H₂O₂-induced pyroptosis by inhibiting the activation of NOD-, LRR- and pyrin domain-containing protein 3. In addition, curcumin improved HUVEC function by restoring αvβ3 and reducing endothelin-1 expression. In conclusion, the results of the present study revealed the mechanism through which curcumin inhibits pyroptosis and indicated that curcumin may have a potential utility in treating diseases of EC dysfunction.

Silencing of LncRNA KCNQ1OT1 confers an inhibitory effect on renal fibrosis through repressing miR-124-3p activity

LncRNA have been increasingly shown that plays pivotal roles in the development of various diseases, including renal fibrosis. Nevertheless, the pathological function of Long non-coding RNA KCNQ1OT1 (KCNQ1OT1) in the renal fibrosis remains obscure. Unilateral ureteral obstruction (UUO) was used to induce renal fibrosis. We detected the expression levels of KCNQ1OT1 in the TGF-β1-induced HK-2 cells via RT-qPCR analysis. The functions of KCNQ1OT1 on the progression of renal fibrosis were examined by CCK-8, EdU, dual-luciferase reporter, and immunofluorescence analyses. In the present study, we found that sh-KCNQ1OT1 obviously attenuated UUO-induced renal fibrosis. Moreover, production of extracellular matrix (ECM), including α-SMA and Fibronectin levels, was significantly increased in kidney and HK-2 cells after UUO or TGF-β stimulation. Knockdown of KCNQ1OT1 inhibited cell proliferation and inhibits the α-SMA and Fibronectin expression of TGF-β1-induced HK-2 cells. In addition, bioinformatics analysis and dual-luciferase reporter assay indicated that miR-124-3p was a target gene of KCNQ1OT1. Mechanistically, silencing miR-124-3p abolished the repressive effects of KCNQ1OT1 on TGF-β1-induced HK-2 cells. In conclusion, KCNQ1OT1 knockdown plays an anti-fibrotic effect through promotion of miR-124-3p expression in renal fibrosis, which provides a promising therapeutic target for the treatment of renal fibrosis.

Cardiac Remodeling in Heart Failure: Role of Pyroptosis and Its Therapeutic Implications

Pyroptosis is a kind of programmed cell death closely related to inflammation. The pathways that mediate pyroptosis can be divided into the Caspase-1-dependent canonical pathway and the Caspase4/5/11-dependent non-canonical pathway. The most significant difference from other cell death is that pyroptosis rapidly causes rupture of the plasma membrane, cell expansion, dissolution and rupture of the cell membrane, the release of cell contents and a large number of inflammatory factors, and send pro-inflammatory signals to adjacent cells, recruit inflammatory cells and induce inflammatory responses. Cardiac remodeling is the basic mechanism of heart failure (HF) and the core of pathophysiological research on the underlying mechanism. A large number of studies have shown that pyroptosis can cause cardiac fibrosis, cardiac hypertrophy, cardiomyocytes death, myocardial dysfunction, excessive inflammation, and cardiac remodeling. Therefore, targeting pyroptosis has a good prospect in improving cardiac remodeling in HF. In this review, the basic molecular mechanism of pyroptosis is summarized, the relationship between pyroptosis and cardiac remodeling in HF is analyzed in-depth, and the potential therapy of targeting pyroptosis to improve adverse cardiac remodeling in HF is discussed, providing some ideas for improving the study of adverse cardiac remodeling in HF.

Regulation of Pyroptosis by ncRNA: A Novel Research Direction

Pyroptosis is a novel form of programmed cell death (PCD), which is characterized by DNA fragmentation, chromatin condensation, cell swelling and leakage of cell contents. The process of pyroptosis is performed by certain inflammasome and executor gasdermin family member. Previous researches have manifested that pyroptosis is closely related to human diseases (such as inflammatory diseases) and malignant tumors, while the regulation mechanism of pyroptosis is not yet clear. Non-coding RNA (ncRNA) such as microRNA (miRNA), long non-coding RNA (lncRNA) and circular RNA (circRNA) have been widely identified in the genome of eukaryotes and played a paramount role in the development of cell function and fate after transcription. Accumulating evidences support the importance of ncRNA biology in the hallmarks of pyroptosis. However, the associations between ncRNA and pyroptosis are rarely reviewed. In this review, we are trying to summarize the regulation and function of ncRNA in cell pyroptosis, which provides a new research direction and ideas for the study of pyroptosis in different diseases.

Comprehensive Bioinformatics Analysis of Gasdermin Family of Glioma

Pyroptosis is a programmed cell death mediated by gasdermins (GSDMs). The prognostic value of pyroptosis-related genes in different tumor types has been gradually demonstrated recently. However, the prognostic impact of GSDMs expression in glioma remains unclear. Here, we present a comprehensive bioinformatic analysis of gasdermin family member gene expression, producing a prognostic model for glioma and creating a competing endogenous RNA (ceRNA) network. The mRNA expression profiles and clinical information of glioma patients were downloaded from TCGA and CGGA. A risk score based on the gasdermin family was constructed in the TCGA cohort and validated in CGGA. The Jurkat cell was used to verify the relationship between pyroptosis and activation-induced cell death (AICD). We identify a significant association between the expression of GSDMD and GSDME and the glioma stage. The least absolute shrinkage and selection operator (LASSO) Cox regression analysis was used to construct a prognostic gene model based on the four prognostic gasdermin family genes (GSDMC, GSDMD, GSDME, and PJVK). This model was able to predict the overall survival of glioma patients with high accuracy. We show that gasdermin family genes are expressed primarily by immune cells, endothelial cells, and neuronal cells in the tumor microenvironment, rather than by malignant tumor cells. T cells were significantly activated in high-risk patients; however, the activation-induced cell death (AICD) pathway was also significantly activated, suggesting widespread expiration of cytotoxic T lymphocytes (CTLs), facilitating tumor progression. We also identify the lncRNA/miR-296-5p/GSDMD regulatory axis as an important player in glioma progression. We have conducted a comprehensive bioinformatic analysis identifying the importance of gasdermin family members in glioma; a prognostic algorithm containing four genes was constructed.

Cellular interplay between cardiomyocytes and non-myocytes in diabetic cardiomyopathy

Patients with Type 2 diabetes mellitus (T2DM) frequently exhibit a distinctive cardiac phenotype known as diabetic cardiomyopathy. Cardiac complications associated with T2DM include cardiac inflammation, hypertrophy, fibrosis and diastolic dysfunction in the early stages of the disease, which can progress to systolic dysfunction and heart failure. Effective therapeutic options for diabetic cardiomyopathy are limited and often have conflicting results. The lack of effective treatments for diabetic cardiomyopathy is due in part, to our poor understanding of the disease development and progression, as well as a lack of robust and valid preclinical human models that can accurately recapitulate the pathophysiology of the human heart. In addition to cardiomyocytes, the heart contains a heterogeneous population of non-myocytes including fibroblasts, vascular cells, autonomic neurons and immune cells. These cardiac non-myocytes play important roles in cardiac homeostasis and disease, yet the effect of hyperglycaemia and hyperlipidaemia on these cell types are often overlooked in preclinical models of diabetic cardiomyopathy. The advent of human induced pluripotent stem cells provides a new paradigm in which to model diabetic cardiomyopathy as they can be differentiated into all cell types in the human heart. This review will discuss the roles of cardiac non-myocytes and their dynamic intercellular interactions in the pathogenesis of diabetic cardiomyopathy. We will also discuss the use of sodium-glucose cotransporter 2 inhibitors as a therapy for diabetic cardiomyopathy and their known impacts on non-myocytes. These developments will no doubt facilitate the discovery of novel treatment targets for preventing the onset and progression of diabetic cardiomyopathy.

Tetrahedral Framework Nucleic Acids Inhibit Skin Fibrosis via the Pyroptosis Pathway

The skin is the first line of defense for the human body and is vulnerable to injury. Various topical or systemic diseases facilitate skin inflammation, and when the intensity or duration of skin injury exceeds the ability of tissue repair, fibrosis, an outcome of a dysregulated tissue-repair response, begins to dominate the repair process. However, existing methods for reducing skin fibrosis are insufficient and cause side effects, highlighting the need for drugs that effectively inhibit skin fibrosis and reduce immunogenicity, inflammation, apoptosis, and pyroptosis. Tetrahedral framework nucleic acids (tFNAs) are DNA nanomaterials that have a unique spatial structure, demonstrate excellent biosecurity, and promote anti-inflammatory, antioxidative, antifibrotic, angiogenic, and skin-wound-healing activities with almost no toxicity. Here, we explored the potential of tFNAs in skin fibrosis therapy in vitro and in vivo. After incubating cells or injecting mice with profibrogenic molecules and tFNAs, we found that the tFNAs inhibited the epithelial-mesenchymal transition, reduced inflammatory factor levels, decreased skin collagen content, and inhibited the pyroptosis pathway. These findings suggest the potential of tFNAs in treating pyroptosis-related diseases.

Co-administration of hydrogen and metformin exerts cardioprotective effects by inhibiting pyroptosis and fibrosis in diabetic cardiomyopathy

Hydrogen is a novel medical gas with several properties, including anti-oxidative, anti-inflammatory, anti-apoptotic, anti-allergic, and energy metabolism stimulating properties. Hydrogen therapy has been proven effective in the treatment of myocardial ischemia, myocardial infarction, and ischemia-reperfusion injury. Diabetic cardiomyopathy (DCM) is a serious cardiovascular complication of long-term chronic diabetes that is linked to increased heart failure and arrhythmia morbidity. The effect of hydrogen on the pathogenesis of DCM is yet to be determined. Metformin is a well-known pharmacological agent for the treatment of diabetes; however, the application of large doses of the drug is limited by its side effects. Therefore, this highlights the importance of developing novel therapies against DCM. In this regard, we investigated the effect of hydrogen on DCM and the mechanisms that underlie it. Furthermore, we also assessed the efficacy of co-administration of metformin and hydrogen. In this study, we found that hydrogen improved cardiac dysfunction and abnormal morphological structure in streptozotocin-induced diabetic mice. As a mechanism, it was confirmed that hydrogen mediated its action by reducing pyroptosis via inhibition of the AMPK/mTOR/NLRP3 signaling pathway and ameliorating fibrosis via inhibition of the TGF-β1/Smad signaling pathway. Furthermore, our findings suggested that co-administration of hydrogen and metformin shows potent protective effects, as evidenced by increased survival rates, reduced fasting blood glucose, and decreased cell injury when compared to a single application of metformin. In conclusion, our study demonstrated that hydrogen inhalation attenuates DCM by reducing pyroptosis and fibrosis and that hydrogen can be combined with metformin to exhibit a more potent cardioprotective effect in DCM.

Long noncoding RNA Kcnq1ot1 prompts lipopolysaccharide-induced acute lung injury by microRNA-7a-5p/Rtn3 axis

Background

Long noncoding RNA (lncRNA)-regulated mechanism in acute lung injury (ALI) has attracted special interests in study researches. We planned to disclose whether KCNQ1 overlapping transcript 1 (Kcnq1ot1) is involved in ALI and its mechanism.

Methods

The lipopolysaccharide (LPS)-induced ALI model was established in mice. Kcnq1ot1, microRNA (miR)-7a-5p and Reticulon 3 (Rtn3) levels were measured in lung tissues of mice. The vector that changed Kcnq1ot1, miR-7a-5p and Rtn3 expression was injected into LPS-treated mice, and pathological damage, fibrosis, apoptosis and inflammatory response were subsequently examined in lung tissues. The relation between Kcnq1ot1 and miR-7a-5p, and that between miR-7a-5p and Rtn3 were identified.

Results

Kcnq1ot1 and Rtn3 expression increased while miR-7a-5p expression decreased in LPS-treated mice. Reduced Kcnq1ot1 or elevated miR-7a-5p alleviated pathological damage, fibrosis, apoptosis and inflammatory response in ALI mice, while overexpressed Rtn3 worsened ALI in mice. Downregulation of Rtn3 reversed the exacerbation of miR-7a-5p downregulation in ALI mice. Kcnq1ot1 competitively bound to miR-7a-5p and miR-7a-5p negatively mediated Rtn3 expression.

Conclusion

Our experiments evidence that silencing Kcnq1ot1 upregulates miR-7a-5p to suppress Rtn3 expression, thereby diminishing LPS-induced ALI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40001-022-00653-8.

Pyroptosis in neurodegenerative diseases: What lies beneath the tip of the iceberg?

Neurodegenerative diseases gradually receive attention with a rapidly aging global population. The hallmark of them is a progressive neuronal loss in the brain or peripheral nervous system due to complex reasons ranging from protein aggregation, immune dysregulation to abnormal cell death. The death style of nerve cell is no longer restricted to apoptosis, autophagy and necrosis as confirmed before. With the successive discoveries of the gasdermin (GSDM) protein family and key caspase molecules in the past several decades, pyroptosis emerges as a novel kind of programmed cell death. A substantial body of evidence has recognized the close connection between pyroptosis and the occurrence and development of neurodegenerative diseases. In this review, we summarize molecular mechanisms of pyroptosis, evidences for pyroptosis involvement in neurodegenerative diseases and finally we hope to provide a novel angle for clinical decision-making.