Dataset Information

Exercise downregulates HIPK2 and HIPK2 inhibition protects against myocardial infarction.

ABSTRACT:

Background

Exercise can protect myocardial infarction (MI) and downregulate cardiac Homeodomain-Interacting Protein Kinase 2 (HIPK2). However, the role of HIPK2 in MI is unclear.

Methods

HIPK2^-/- mice and miR-222^-/- rats, HIPK2 inhibitor (PKI1H) and adeno-associated virus serotype 9 (AAV9) carrying miR-222 were applied in the study. Animals were subjected to running, swimming, acute MI or post-MI remodeling. HIPK2 inhibition and P53 activator were used in neonatal rat cardiomyocytes (NRCMs) and human embryonic stem cell-derived cardiomyocytes (hESC-CMs) subjected to oxygen glucose deprivation/reperfusion (OGD/R). Serum miR-222 levels were analyzed in healthy people and MI patients that were survival or readmitted to the hospital and/or died.

Findings

Cardiac HIPK2 protein levels were reduced by exercise while increased in MI. In vitro, HIPK2 suppression by lentiviral vectors or inhibitor prevented apoptosis induced by OGD/R in NRCMs and hESC-CMs. HIPK2 inhibitor-treated mice and HIPK2^-/- mice reduced infarct size after acute MI, and preserved cardiac function in MI remodeling. Mechanistically, protective effect against apoptosis by HIPK2 suppression was reversed by P53 activators. Furthermore, increasing levels of miR-222, targeting HIPK2, protected post-MI cardiac dysfunction, whereas cardiac dysfunction post-MI was aggravated in miR-222^-/- rats. Moreover, serum miR-222 levels were significantly reduced in MI patients, as well as in MI patients that were readmitted to the hospital and/or died compared to those not.

Interpretation

Exercise-induced HIPK2 suppression attenuates cardiomyocytes apoptosis and protects MI by decreasing P-P53. Inhibition of HIPK2 represents a potential novel therapeutic intervention for MI.

Funding

This work was supported by the grants from National Key Research and Development Project (2018YFE0113500 to JJ Xiao), National Natural Science Foundation of China (82020108002, 81722008, and 81911540486 to JJ Xiao, 81400647 to MJ Xu, 81800265 to YJ Liang), Innovation Program of Shanghai Municipal Education Commission (2017-01-07-00-09-E00042 to JJ Xiao), the grant from Science and Technology Commission of Shanghai Municipality (18410722200 and 17010500100 to JJ Xiao), the "Dawn" Program of Shanghai Education Commission (19SG34 to JJ Xiao), Shanghai Sailing Program (21YF1413200 to QL Zhou). JS is supported by Horizon2020 ERC-2016-COG EVICARE (725229).

SUBMITTER: Zhou Q

PROVIDER: S-EPMC8626841 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:RationaleThioredoxin-interacting protein (Txnip) is a novel molecular target with translational potential in diverse human diseases. Txnip has several established cellular actions including binding to thioredoxin, a scavenger of reactive oxygen species (ROS). It has been long recognized from in vitro evidence that Txnip forms a disulfide bridge through cysteine 247 (C247) with reduced thioredoxin to inhibit the anti-oxidative properties of thioredoxin. However, the physiological significance of the Txnip-thioredoxin interaction remains largely undefined in vivo.ObjectiveA single mutation of Txnip, C247S, abolishes the binding of Txnip with thioredoxin. Using a conditional and inducible approach with a mouse model of a mutant Txnip that does not bind thioredoxin, we tested whether the interaction of thioredoxin with Txnip is required for Txnip's pro-oxidative or cytotoxic effects in the heart.Methods and resultsOverexpression of Txnip C247S in cells resulted in a reduction in ROS, due to an inability to inhibit thioredoxin. Hypoxia (1% O2, 24 h)-induced killing effects of Txnip were decreased by lower levels of cellular ROS in Txnip C247S-expressing cells compared with wild-type Txnip-expressing cells. Then, myocardial ischemic injuries were assessed in the animal model. Cardiomyocyte-specific Txnip C247S knock-in mice had better survival with smaller infarct size following myocardial infarction (MI) compared to control animals. The absence of Txnip's inhibition of thioredoxin promoted mitochondrial anti-oxidative capacities in cardiomyocytes, thereby protecting the heart from oxidative damage induced by MI. Furthermore, an unbiased RNA sequencing screen identified that hypoxia-inducible factor 1 signaling pathway was involved in Txnip C247S-mediated cardioprotective mechanisms.ConclusionTxnip is a cysteine-containing redox protein that robustly regulates the thioredoxin system via a disulfide bond-switching mechanism in adult cardiomyocytes. Our results provide the direct in vivo evidence that regulation of redox state by Txnip is a crucial component for myocardial homeostasis under ischemic stress.

Project description:BackgroundHomeodomain-Interacting Protein Kinase 2 (HIPK2) has been reported to maintain basal cardiac function, however, its role in pathological cardiac remodeling remains unclear.MethodsHIPK2 inhibitors (tBID and PKI1H) treated mice and two lines of HIPK2-/- mice were subjected to transverse aortic constriction (TAC). HIPK2 knockdown were performed in neonatal rat cardiomyocytes (NRCMs), neonatal rat cardiac fibroblasts (NRCFs), and human embryonic stem cell-derived cardiomyocytes (hESC-CMs). Microarray analysis was used to screen HIPK2 targets. Overexpression of early growth response 3 (EGR3) and C-type lectin receptor 4D (CLEC4D) were performed in NRCMs, while an activator of Smad3 was used in NRCFs, to rescue the effects of HIPK2 knockdown. Finally, the effects of EGR3 and CLEC4D knockdown by AAV9 in TAC were determined.FindingsHIPK2 was elevated in TAC mice model, as well as cardiomyocyte hypertrophy and NRCFs fibrosis model. Pharmacological and genetic inhibition of HIPK2 improved cardiac function and suppressed cardiac hypertrophy and fibrosis induced by TAC. In vitro, HIPK2 inhibition prevented cardiomyocyte hypertrophic growth and NRCFs proliferation and differentiation. At the mechanistic level, we identified EGR3 and CLEC4D as new targets of HIPK2, which were regulated by ERK1/2-CREB and mediated the protective function of HIPK2 inhibition in cardiomyocytes. Meanwhile, inhibition of phosphorylation of Smad3 was responsible for the suppression of cardiac fibroblasts proliferation and differentiation by HIPK2 inhibition. Finally, we found that inhibition of EGR3 or CLEC4D protected against TAC.InterpretationHIPK2 inhibition protects against pathological cardiac remodeling by reducing EGR3 and CLEC4D with ERK1/2-CREB inhibition in cardiomyocytes, and by suppressing the phosphorylation of Smad3 in cardiac fibroblasts.FundingThis work was supported by the grants from National Key Research and Development Project (2018YFE0113500 to J.X.), National Natural Science Foundation of China (82020108002 and 81911540486 to J.X., 81400647 to MJ Xu), the grant from Science and Technology Commission of Shanghai Municipality (21XD1421300 and 20DZ2255400 to J.X.), the "Dawn" Program of Shanghai Education Commission (19SG34 to J.X.), and Shanghai Sailing Program (21YF1413200 to Q.Z.).

Project description:PurposeOestrogen receptor β is believed to exert a cardioprotective effect against ischaemic injury. Nonetheless, the mechanism underlying its protective action remains to be fully elucidated. Recently, increased attention has been focused on Notch1 signalling for ameliorating cardiac ischaemic injury. Here, we hypothesised that oestrogen receptor β activation attenuates myocardial infarction (MI)-induced cardiac damage by modulating the Notch1 signalling pathway.MethodsMale C57BL/6 mice were used to establish an MI model through the ligation of the anterior descending branch of the left coronary artery. Two chemical drugs, 2,3-Bis(4-hydroxyphenyl)-propionitrile (DPN) and N-[N-(3,5-difluorophenacetyl)-l-alanyl]-s-phenylglycine t-butyl ester (DAPT), a specific inhibitor of Notch1 signalling) were administered via intraperitoneal injection to change oestrogen receptor β and Notch1 activities. Immunohistochemistry, western blot analysis, enzyme-linked immunosorbent assay (Elisa) assessment and echocardiography were used in this study to analyse cardiac oxidative stress, apoptosis, infraction volume, fibrosis and cardiac function.ResultsDPN-mediated oestrogen receptor β activation effectively protected cardiomyocytes from MI-induced oxidative damage and apoptosis. Furthermore, oestrogen receptor β activation reduced the infarct size and lowered the levels of myocardial enzymes in the serum, thereby leading to greater overall cardiac function improvement. Ischaemic injury-induced myocardial fibrosis was attenuated by oestrogen receptor β activation. Nevertheless, all of these cardioprotective effects of oestrogen receptor β activation were almost abrogated by DAPT administration, i.e. DAPT attenuated the anti-oxidative and anti-apoptotic effects and the decrease in infarct and fibrotic areas and reversed cardiac functional recovery. The levels of phospho-phosphatidylinositol-3-kinase (PI3K) and phospho-protein kinase B (Akt) were increased after DPN administration, and this change was reversed after DAPT was administered.ConclusionsAll of these new findings indicate that oestrogen receptor β activation is effective in ameliorating MI-induced cardiac dysfunction by enhancing Notch1 signalling and that PI3K/Akt signalling is the downstream mediator.