NPAS2 ameliorates myocardial ischaemia/reperfusion injury in rats via CX3CL1 pathways and regulating autophagy.
Ontology highlight
ABSTRACT: Background
Myocardial ischemia/reperfusion (I/R) injury is common during the treatment of cardiovascular diseases. Neuronal PAS Domain Protein 2 (NPAS2) is one of the core genes that control the rhythm of the biological clock. NPAS2 also regulates the biological rhythm.Results
The rat I/R model showed that the expression of NPAS2 decreased with the increase of reperfusion time. Overexpressing NPAS2 adenovirus (ad-NPAS2) was injected into IR rat which demonstrated that ad-NPAS2 ameliorated rats I/R injury. A hypoxia/reoxygenation (H/R) model in rat cardiomyocytes showed that ad-NPAS2 inhibited cardiomyocyte apoptosis. Co-Immunoprecipitation results showed that there is an interaction between NPAS2 and Cry2. Knockdown of Cry2 aggravated the cardiomyocyte apoptosis induced by H/R. Additionally, NPAS2 directly act on the promoter region of CX3CL1. Knockdown of CX3CL1 reverse the protective effect of ad-NPAS2 on rat myocardial ischemia-reperfusion injury and H/R-induced cardiomyocyte apoptosis. CX3CL1 also regulates autophagy through the downstream AKT/mTOR pathway.Conclusions
research demonstrated that overexpression of NPAS2 interacts with Cry2 and promotes the transcriptional activity of CX3CL1. Moreover, overexpression of NPAS2 regulates the downstream AKT/mTOR pathway to inhibit autophagy in order to improve rat cardiac I/R injury.
SUBMITTER: Huang J
PROVIDER: S-EPMC8436934 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:BACKGROUND AND PURPOSE:Antioxidants provide a promising therapeutic effect for the cardiovascular disease. Luteolin, a polyphenolic bioflavonoid, is known to confer cardioprotection, although the underlying mechanisms, especially the role of luteolin on the antioxidant enzymes, such as the peroxiredoxin family, remain unknown. EXPERIMENTAL APPROACH:We measured the effects of luteolin on myocardial ischaemia/reperfusion (MI/R) injury in vivo (Sprague-Dawley rats) and in vitro, together with the underlying mechanisms, with a focus on signalling by peroxiredoxins. H9c2 cells were used to assess the changes in peroxiredoxins and the other antioxidant enzymes. Oxidative stress, cardiac function, LDH release, ROS and infarct size were also assayed. KEY RESULTS:Luteolin exerted significant cardioprotective effects in vivo and in vitro via improving cardiac function, increasing the expression of anti-apoptotic protein Bcl-2 and decreasing the pro-apoptotic protein Bax and active caspases 3 and 9, associated with MI/R. Mechanistically, luteolin markedly enhanced expression of peroxiredoxin II, without significant effects on other forms of peroxiredoxin, catalase or SOD1. Molecular docking showed that luteolin could indeed bind to the enzymic active pocket of peroxiredoxin II. Furthermore, down-regulation of peroxiredoxin II by peroxiredoxin II-antisense, administered by adenovirus infection of H9c2 cardiomyocytes, and inhibition of peroxiredoxin II in vivo significantly reversed the cardioprotective effects of luteolin. CONCLUSIONS AND IMPLICATIONS:Our findings, for the first time, demonstrate that luteolin protects against MI/R injury through promoting signalling through the endogenous antioxidant enzyme, peroxiredoxin II, indicating the important beneficial role of this antioxidant system in the heart.
| S-EPMC6057904 | biostudies-literature
Project description:Background: Myocardial ischaemia/reperfusion (I/R) results in myocardial injury via excessive autophagy. Huoxue Jiedu Formula (HJF) has been widely applied in China for the treatment of ischaemic heart disease. However, the mechanisms of HJF are still poorly understood. Thus, the present experiment was designed to observe the effects of HJF on myocardial I/R injury and explore the possible mechanism. Methods: Myocardial injury in rats subjected to myocardial I/R was reflected by nitrotetrazolium blue chloride staining, thioflavin S staining, serum creatine kinase-MB (CK-MB) and cardiac troponin T (cTnT). Autophagy was determined by electron microscopy, laser confocal microscopy, Q-PCR and western blot. The possible pathway was predicted by network pharmacology and validated in vivo and in vitro. Results: Pretreatment of HJF decreased the no-reflow area, infarcted area, serum CK-MB levels and serum cTnT levels in I/R rat model. In addition, pretreatment of HJF decreased autophagy in heart tissues (decrease in Beclin-1 and LC3-II, and increase in Bcl-2, p62 and ratio of LC3-I/LC3-II). In the vivo study, pretreatment of HJF significantly decreased hypoxia/reoxygenation (H/R)-induced autophagy in H9C2 cells. Network pharmacology was applied to predict the possible mechanism by which HJF affects cardiac autophagy, and the PI3K/AKT/mTOR signalling pathway was the most significantly enriched pathway. And experimental studies demonstrated that pretreatment of HJF increased the phosphorylation of AKT and mTOR, and the effects of HJF on autophagy would be offset by PI3K inhibitor LY294002. Conclusion: Pretreatment of HJF ameliorates myocardial I/R injury by decreasing autophagy through activating PI3K/AKT/mTOR pathway.
| S-EPMC7952439 | biostudies-literature
Project description:Cardiovascular disease (CVD) is the leading cause of the death worldwide. An increasing number of studies have found that autophagy is involved in the progression or prevention of CVD. However, the precise mechanism of autophagy in CVD, especially the myocardial ischaemia-reperfusion injury (MI/R injury), is unclear and controversial. Here, we show that the cardiomyocyte-specific disruption of autophagy by conditional knockout of Atg7 leads to severe contractile dysfunction, myofibrillar disarray and vacuolar cardiomyocytes. A negative cytoskeleton organization regulator, CLP36, was found to be accumulated in Atg7-deficient cardiomyocytes. The cardiomyocyte-specific knockout of Atg7 aggravates the MI/R injury with cardiac hypertrophy, contractile dysfunction, myofibrillar disarray and severe cardiac fibrosis, most probably due to CLP36 accumulation in cardiomyocytes. Altogether, this work reveals autophagy may protect cardiomyocytes from the MI/R injury through the clearance of CLP36, and these findings define a novel relationship between autophagy and the regulation of stress fibre in heart.
| S-EPMC5008017 | biostudies-literature
Project description:BackgroundIschaemic preconditioning elicited by brief periods of coronary occlusion and reperfusion protects the heart from a subsequent prolonged ischaemic insult. Here, we test the hypothesis that short-term non-ischaemic stimulation of hypertrophy renders the heart resistant to subsequent ischaemic injury.Methods and resultsTransient transverse aortic constriction (TAC) was performed for 3 days in mice and then withdrawn for 4 days by aortic debanding, followed by subsequent exposure to myocardial ischaemia-reperfusion (I/R) injury. Following I/R injury, myocardial infarct size and apoptosis were significantly decreased, and cardiac dysfunction was markedly improved in the TAC preconditioning group compared with the control group. Mechanistically, TAC preconditioning markedly suppressed I/R-induced autophagy and preserved autophagic flux by deacetylating SOD2 via a SIRT3-dependent mechanism. Moreover, treatment with an adenovirus encoding SIRT3 partially mimicked the effects of hypertrophic preconditioning, whereas genetic ablation of SIRT3 in mice blocked the cardioprotective effects of hypertrophic preconditioning. Furthermore, in vivo lentiviral-mediated knockdown of Beclin 1 in the myocardium ameliorated the I/R-induced impairment of autophagic flux and was associated with a reduction in cell death, whereas treatment with a lentivirus encoding Beclin 1 abolished the cardioprotective effect of TAC preconditioning.ConclusionsThe present study identifies TAC preconditioning as a novel strategy for induction of an endogenous self-defensive and cardioprotective mechanism against cardiac injury. Specifically, TAC preconditioning reduced myocardial autophagic cell death in a SIRT3/SOD2 pathway-dependent manner.
| S-EPMC8249780 | biostudies-literature
Project description:AimsThrombopoietin (Tpo) is known for its ability to stimulate platelet production. However, it is currently unknown whether Tpo plays a physiological function in the heart.Methods and resultsWe assessed the potential protective role of Tpo in vitro and in vivo in two rat models of myocardial ischaemia/reperfusion. Tpo receptor (c-mpl) message was detected in the heart using RT-PCR, and the Tpo receptor protein was detected using western blotting and immunohistochemistry. Tpo treatment immediately before ischaemia reduced myocardial necrosis, apoptosis, and decline in ventricular function following ischaemia/reperfusion in the rat in a concentration- and dose-dependent manner with an optimal concentration of 1.0 ng/mL in vitro and an optimal dose of 0.05 microg/kg iv in vivo. Tpo also reduced infarct size when given after the onset of ischaemia or at reperfusion. Tpo activated JAK-2 (Janus kinase-2) and p44 MAPK (mitogen-activated protein kinase) during reperfusion but not prior to ischaemia. Inhibition of JAK-2 (AG-490), p42/44 MAPK (PD98059), mitochondrial K(ATP) channels (5-HD), and sarcolemmal K(ATP) channels (HMR 1098) abolished Tpo-induced resistance to injury from myocardial ischaemia/reperfusion. AG-490, PD98059, 5-HD, and HMR1098 alone had no effect on cardioprotection. Treatment with a single dose of Tpo (0.05 or 1.0 microg/kg iv) did not result in the elevation of platelet count or haematocrit over a 16-day period.ConclusionA single treatment of Tpo confers cardioprotection through JAK-2, p42/44 MAPK, and K(ATP) channels, suggesting a potential therapeutic role of Tpo in the treatment of injury resulting from myocardial ischaemia and reperfusion.
| S-EPMC2958050 | biostudies-literature
Project description:Transforming growth factor ?-activated protein kinase 1 (TAK1) involves in various biological responses and is a key regulator of cell death. However, the role of TAK1 on acute myocardial ischaemia/reperfusion (MI/R) injury is unknown. We observed that TAK1 activation increased significantly after MI/R and hypoxia/reoxygenation (H/R), and we hypothesized that TAK1 has an important role in MI/R injury. Mice (TAK1 inhibiting by 5Z-7-oxozeaenol or silencing by AAV9 vector) were exposed to MI/R injury. Primary cardiomyocytes (TAK1 silencing by siRNA; and overexpressing TAK1 by adenovirus vector) were used to induce H/R injury model in vitro. Inhibition of TAK1 significantly decreased MI/R-induced myocardial infarction area, reduced cell death and improved cardiac function. Mechanistically, TAK1 silencing suppressed MI/R-induced myocardial oxidative stress and attenuated endoplasmic reticulum (ER) stress both in vitro and in vivo. In addition, the inhibition of ROS by NAC partially reversed the damage of TAK1 in vitro. Our study presents the first direct evidence that inhibition of TAK1 mitigated MI/R injury, and TAK1 mediated ROS/ER stress/apoptosis signal pathway is important for the pathogenesis of MI/R injury.
| S-EPMC7299680 | biostudies-literature
Project description:BACKGROUND AND PURPOSE:Nicorandil, an ATP-sensitive potassium (K(ATP) ) channel opener and nitric oxide donor, is used in the treatment of angina and acute heart failure. Here we investigated the effects of two K(ATP) channel openers, nicorandil and cromakalim on ischaemia reperfusion (I-R) injury in the kidney. EXPERIMENTAL APPROACH:Right nephrectomy was performed in 8-week-old male Sprague-Dawley rats and they were then divided into six groups: control group; I-R, including 30 min of left renal ischaemia followed by 24 h of reperfusion; I-R groups plus nicorandil 3 or 10 mg·kg?¹ i.p.; and I-R groups plus cromakalim 100 or 300 µg·kg?¹ i.p. After reperfusion, renal function was estimated by serum creatinine (SCr), urinary albumin:creatinine ratio (ACR) and urinary ?2-microglobulin (?2-MG). Levels of K(ATP) channel subtypes were investigated by Western blot. Kidney sections were stained for 4-hydroxy-2-nonenal and 8-hydroxy-2'-deoxyguanosine. KEY RESULTS:Renal I-R induced significant increases in SCr, ACR and ?2-MG levels compared with the control animals. Treatment with K(ATP) channel openers reduced urinary ?2-MG levels, raised by I-R. Both K(IR) 6.1 and K(IR) 6.2 channels were expressed. Expression of K(IR) 6.2 channels in the I-R group was lower than in the control group, which was restored to normal by treatment with K(ATP) channel openers. Histologically, severe acute tubular damage was observed in the I-R kidney and this damage was ameliorated by K(ATP) channel openers, dose-dependently. CONCLUSIONS AND IMPLICATIONS:ATP-sensitive potassium channel openers protected against proximal tubule damage after I-R injury. Nicorandil could represent a powerful additional component in the treatment of patients undergoing partial nephrectomy or renal transplantation.
| S-EPMC3087131 | biostudies-literature
Project description:AimsThe present study was designed to examine the mechanism involved in mitochondrial aldehyde dehydrogenase (ALDH2)-induced cardioprotection against ischaemia/reperfusion (I/R) injury with a focus on autophagy.MethodsWild-type (WT), ALDH2 overexpression, and knockout (KO) mice (n = 4-6 for each index measured) were subjected to I/R, and myocardial function was assessed using echocardiographic, Langendroff, and edge-detection systems. Western blotting was used to evaluate AMP-dependent protein kinase (AMPK), Akt, autophagy, and the AMPK/Akt upstream signalling LKB1 and PTEN.ResultsALDH2 overexpression and KO significantly attenuated and accentuated, respectively, infarct size, factional shortening, and recovery of post-ischaemic left ventricular function following I/R as well as hypoxia/reoxygenation-induced cardiomyocyte contractile dysfunction. Autophagy was induced during ischaemia and remained elevated during reperfusion. ALDH2 significantly promoted autophagy during ischaemia, which was accompanied by AMPK activation and mammalian target of rapamycin (mTOR) inhibition. On the contrary, ALDH2 overtly inhibited autophagy during reperfusion accompanied by the activation of Akt and mTOR. Inhibition and induction of autophagy mitigated ALDH2-induced protection against cell death in hypoxia and reoxygenation, respectively. In addition, levels of the endogenous toxic aldehyde 4-hydroxy-2-nonenal (4-HNE) were elevated by ischaemia and reperfusion, which was abrogated by ALDH2. Furthermore, ALDH2 ablated 4-HNE-induced cardiomyocyte dysfunction and protein damage, whereas 4-HNE directly decreased pan and phosphorylated LKB1 and PTEN expression.ConclusionOur data suggest a myocardial protective effect of ALDH2 against I/R injury possibly through detoxification of toxic aldehyde and a differential regulation of autophagy through AMPK- and Akt-mTOR signalling during ischaemia and reperfusion, respectively.
| S-EPMC3076664 | biostudies-literature
Project description:Despite improvements in revascularization after a myocardial infarction, coronary disease remains a major contributor to global mortality. Neutrophil infiltration and activation contributes to tissue damage, via the release of myeloperoxidase (MPO) and formation of the damaging oxidant hypochlorous acid. We hypothesized that elevation of thiocyanate ions (SCN-), a competitive MPO substrate, would modulate tissue damage. Oral dosing of rats with SCN-, before acute ischemia-reperfusion injury (30 min occlusion, 24 h or 4 week recovery), significantly reduced the infarct size as a percentage of the total reperfused area (54% versus 74%), and increased the salvageable area (46% versus 26%) as determined by MRI imaging. No difference was observed in fractional shortening, but supplementation resulted in both left-ventricle end diastolic and left-ventricle end systolic areas returning to control levels, as determined by echocardiography. Supplementation also decreased antibody recognition of HOCl-damaged myocardial proteins. SCN- supplementation did not modulate serum markers of damage/inflammation (ANP, BNP, galectin-3, CRP), but returned metabolomic abnormalities (reductions in histidine, creatine and leucine by 0.83-, 0.84- and 0.89-fold, respectively), determined by NMR, to control levels. These data indicate that elevated levels of the MPO substrate SCN-, which can be readily modulated by dietary means, can protect against acute ischemia-reperfusion injury.
| S-EPMC8209016 | biostudies-literature
Project description:The circadian clock is closely related to the development of diabetes mellitus and cardiovascular disease, and disruption of the circadian clock exacerbates myocardial ischaemia/reperfusion injury (MI/RI). HDAC3 is a key component of the circadian negative feedback loop that controls the expression pattern of the circadian nuclear receptor Rev-erbα to maintain the stability of circadian genes such as BMAL1. However, the mechanism by which the HDAC3-orchestrated Rev-erbα/BMAL1 pathway increases MI/RI in diabetes and its relationship with mitophagy have yet to be elucidated. Here, we observed that the clock genes Rev-erbα, BMAL1, and C/EBPβ oscillations were altered in the hearts of rats with streptozotocin (STZ)-induced diabetes, with upregulated HDAC3 expression. Oscillations of Rev-erbα and BMAL1 were rapidly attenuated in diabetic MI/R hearts versus non-diabetic I/RI hearts, in accordance with impaired and rhythm-disordered circadian-dependent mitophagy that increased injury. Genetic knockdown of HDAC3 significantly attenuated diabetic MI/RI by mediating the Rev-erbα/BMAL1 circadian pathway to recover mitophagy. Primary cardiomyocytes with or without HDAC3 siRNA and Rev-erbα siRNA were exposed to hypoxia/reoxygenation (H/R) in vitro. The expression of HDAC3 and Rev-erbα in cardiomyocytes was increased under high-glucose conditions compared with low-glucose conditions, with decreased BMAL1 expression and mitophagy levels. After H/R stimulation, high glucose aggravated H/R injury, with upregulated HDAC3 and Rev-erbα expression and decreased BMAL1 and mitophagy levels. HDAC3 and Rev-erbα siRNA can alleviate high glucose-induced and H/R-induced injury by upregulating BMAL1 to increase mitophagy. Collectively, these findings suggest that disruption of HDAC3-mediated circadian gene expression oscillations induces mitophagy dysfunction, aggravating diabetic MI/RI. Cardiac-specific HDAC3 knockdown could alleviate diabetic MI/RI by regulating the Rev-erbα/BMAL1 pathway to restore the activation of mitophagy.
| S-EPMC7791027 | biostudies-literature