scholarly journals Immunoreactivity of the SARS-CoV-2 entry proteins ACE-2 and TMPRSS-2 in murine models of hormonal manipulation, ageing, and cardiac injury

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Susan Bengs ◽  
Alexia Rossi ◽  
Martina Haberecker ◽  
Nidaa Mikail ◽  
Alexander Meisel ◽  
...  

AbstractPrevious work indicates that SARS-CoV-2 virus entry proteins angiotensin-converting enzyme 2 (ACE-2) and the cell surface transmembrane protease serine 2 (TMPRSS-2) are regulated by sex hormones. However, clinical studies addressing this association have yielded conflicting results. We sought to analyze the impact of sex hormones, age, and cardiovascular disease on ACE-2 and TMPRSS-2 expression in different mouse models. ACE-2 and TMPRSS-2 expression was analyzed by immunostaining in a variety of tissues obtained from FVB/N mice undergoing either gonadectomy or sham-surgery and being subjected to ischemia–reperfusion injury or transverse aortic constriction surgery. In lung tissues sex did not have a significant impact on the expression of ACE-2 and TMPRSS-2. On the contrary, following myocardial injury, female sex was associated to a lower expression of ACE-2 at the level of the kidney tubules. In addition, after myocardial injury, a significant correlation between younger age and higher expression of both ACE-2 and TMPRSS-2 was observed for lung alveoli and bronchioli, kidney tubules, and liver sinusoids. Our experimental data indicate that gonadal hormones and biological sex do not alter ACE-2 and TMPRSS-2 expression in the respiratory tract in mice, independent of disease state. Thus, sex differences in ACE-2 and TMPRSS-2 protein expression observed in mice may not explain the higher disease burden of COVID-19 among men.

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Bo Yang ◽  
Li’e Zang ◽  
Jingwen Cui ◽  
Linlin Wei

Abstract Background Stroke serves as a prevalent cerebrovascular disorder with severe cerebral ischemia/reperfusion (CIR) injury, in which neural stem cells (NSCs) play critical roles in the recovery of cerebral function. Circular RNAs (circRNAs) have been widely found to participate in stroke and NSC modulation. However, the role of circRNA TTC3 (circTTC3) in the regulation of CIR injury and NSCs remains elusive. Here, we aimed to explore the impact of circTTC3 on CIR injury and NSCs. Methods The middle cerebral artery occlusion/repression (MCAO/R) model was established in C57BL/6J mice. The primary astrocytes were isolated from the cerebellum from C57BL/6J mice. The primary NSCs were obtained from rat embryos. The effect of circTTC3 on CIR injury and NSCs was analyzed by TTC staining, qPCR, Western blot, LDH colorimetric kits, MTT assays, Annexin V-FITC Apoptosis Detection Kit, luciferase reporter gene assays, and others in the system. Results Significantly, the expression of circTTC3 was elevated in the MCAO/R mice and oxygen and glucose deprivation (OGD)-treated astrocytes. The depletion of circTTC3 attenuated cerebral infarction, neurological score, and brain water content. The OGD treatment induced apoptosis and the levels of lactate dehydrogenase (LDH) in the astrocytes, in which circTTC3 depletion reduced this phenotype in the system. Moreover, the depletion of circTTC3 promoted the proliferation and upregulated the nestin and β-tubulin III expression in NSCs. Mechanically, circTTC3 was able to sponge miR-372-3p, and miR-372-3p can target Toll-like receptor 4 (TLR4) in NSCs. The miR-372-3p inhibitor or TLR4 overexpression could reverse circTTC3 depletion-mediated astrocyte OGD injury and NSC regulation. Conclusion Thus, we conclude that circTTC3 regulates CIR injury and NSCs by the miR-372-3p/TLR4 axis in cerebral infarction. Our finding presents new insight into the mechanism by which circTTC3 modulates CIR injury and NSC dysfunction. CircTTC3, miR-372-3p, and TLR4 may serve as potential targets for the treatment of CIR injury during stroke.


Author(s):  
Kang Zhou ◽  
Yan Xu ◽  
Qiong Wang ◽  
Lini Dong

Abstract Myocardial injury is still a serious condition damaging the public health. Clinically, myocardial injury often leads to cardiac dysfunction and, in severe cases, death. Reperfusion of the ischemic myocardial tissues can minimize acute myocardial infarction (AMI)-induced damage. MicroRNAs are commonly recognized in diverse diseases and are often involved in the development of myocardial ischemia/reperfusion injury. However, the role of miR-431 remains unclear in myocardial injury. In this study, we investigated the underlying mechanisms of miR-431 in the cell apoptosis and autophagy of human cardiomyocytes in hypoxia/reoxygenation (H/R). H/R treatment reduced cell viability, promoted cell apoptotic rate, and down-regulated the expression of miR-431 in human cardiomyocytes. The down-regulation of miR-431 by its inhibitor reduced cell viability and induced cell apoptosis in the human cardiomyocytes. Moreover, miR-431 down-regulated the expression of autophagy-related 3 (ATG3) via targeting the 3ʹ-untranslated region of ATG3. Up-regulated expression of ATG3 by pcDNA3.1-ATG3 reversed the protective role of the overexpression of miR-431 on cell viability and cell apoptosis in H/R-treated human cardiomyocytes. More importantly, H/R treatments promoted autophagy in the human cardiomyocytes, and this effect was greatly alleviated via miR-431-mimic transfection. Our results suggested that miR-431 overexpression attenuated the H/R-induced myocardial damage at least partly through regulating the expression of ATG3.


2006 ◽  
Vol 290 (3) ◽  
pp. C719-C727 ◽  
Author(s):  
Frank C. Chen ◽  
Ozgur Ogut

The severity and duration of ischemia-reperfusion injury is hypothesized to play an important role in the ability of the heart subsequently to recover contractility. Permeabilized trabeculae were prepared from a rat model of ischemia-reperfusion injury to examine the impact on force generation. Compared with the control perfused condition, the maximum force (Fmax) per cross-sectional area and the rate of tension redevelopment of Ca2+-activated trabeculae fell by 71% and 44%, respectively, during ischemia despite the availability of a high concentration of ATP. The reduction in Fmax with ischemia was accompanied by a decline in fiber stiffness, implying a drop in the absolute number of attached cross bridges. However, the declines during ischemia were largely recovered after reperfusion, leading to the hypothesis that intrinsic, reversible posttranslational modifications to proteins of the contractile filaments occur during ischemia-reperfusion injury. Examination of thin-filament proteins from ischemic or ischemia-reperfused hearts did not reveal proteolysis of troponin I or T. However, actin was found to be glutathionylated with ischemia. Light-scattering experiments demonstrated that glutathionylated G-actin did not polymerize as efficiently as native G-actin. Although tropomyosin accelerated the time course of native and glutathionylated G-actin polymerization, the polymerization of glutathionylated G-actin still lagged native G-actin at all concentrations of tropomyosin tested. Furthermore, cosedimentation experiments demonstrated that tropomyosin bound glutathionylated F-actin with significantly reduced cooperativity. Therefore, glutathionylated actin may be a novel contributor to the diverse set of posttranslational modifications that define the function of the contractile filaments during ischemia-reperfusion injury.


Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Haobo Li ◽  
Michael G Irwin ◽  
Zhengyuan Xia

Introduction: Signal transducer and activator of transcription 3 (STAT3) plays a key role in postconditioning (IPo) mediated protection against myocardial ischemia reperfusion injury, but the mechanism by which IPo activates STAT3 is unknown. Adiponectin (APN), a protein with anti-ischemic properties, activates STAT3. We hypothesized that IPo activates mitochondrial STAT3 (MitoSTAT3) via APN signaling. Methods and Results: Wild type (WT) and APN knockout (KO) mice were either sham operated or subjected to 30 min of coronary artery occlusion followed by 2 hours of reperfusion with or without IPo (3 cycles of 10 seconds reperfusion and 10 seconds reocclusion; n=8/group). At the end of reperfusion, KO mice exhibited more severe myocardial injury evidenced as increased infarct size (% of area at risk) 49.2±2.0 vs WT 39.4±3.5, P <0.01; plasma troponin I (ng/ml): KO 72.8±7.6 vs WT 45.7±4.0, P <0.01; worse cardiac function (lower dP/dt max and end-systolic pressure-volume relation, P <0.05); more severely impaired mitochondrial function (reductions in complex IV and complex V protein expression) and more severe reduction of MitoSTAT3 phosphorylation (activation) at site Ser727, P <0.01. IPo significantly attenuated post-ischemic cardiac injury and dysfunction with a concomitant increase in phosphorylated MitoSTAT3 and attenuation of mitochondrial dysfunction in WT (all P <0.05) but not in KO mice. In cultured cardiac H9C2 cells, hypoxic postconditioning (HPo, 3 cycles of 5 min hypoxia and 5 min reoxygenation) significantly attenuated hypoxia/reoxygenation (HR, 3 hours hypoxia/3 hours reoxygenation) induced cell injury (increased apoptotic cell death as % of HR): HR 100.2±0.4 vs HPo 78.2±4.8, P <0.05) and reduced mitochondrial transmembrane potential (% total cells, HR 37.2±4.9 vs HPo 23.5±3.7, P <0.01). APN, adiponectin receptor 1 (AdipoR1), or STAT3 gene knockdown but not AdipoR2 gene knockdown, respectively, abolished HPo cellular protection (all P <0.05 vs. HPo). APN supplementation (10μg/ml) restored HPo protection in cells with APN knockdown but not in cells with AdipoR1or STAT3 gene knockdown. Conclusion: Adiponectin and AdipoR1 signaling are required for IPo to activate myocardial mitochondrial STAT3 to confer cardioprotection.


2021 ◽  
Vol 19 (4) ◽  
pp. 543-549
Author(s):  
Fanglin Luo ◽  
Shunxiang Luo ◽  
Yanqing Wu

Using a rat model, we have explored the underlying mechanism of ischemia/reperfusion (I/R)-mediated myocardial infarction and assessed the protective potential of zingerone. The results show that zingerone exhibits not only the myocardial protective effect, but also antioxidative and anti-inflammatory effects by suppression of markers of oxidation and proinflammatory cytokine release. Zingerone promotes protective effects against I/R-induced myocardial infarction by regulating Nrf2/HO-1 and NF-κB signaling pathways. These findings provide novel insights into the effects of zingerone on the cardioprotective mechanism of myocardial injury after I/R and may open new avenues for myocardial infarction treatment.


2014 ◽  
Vol 115 (suppl_1) ◽  
Author(s):  
Jingyuan li ◽  
Zoltan Pierre Arany ◽  
Mansoureh Eghbali

Angiogenesis plays an important role in the pathogenesis of cardiovascular disease. Pro-angiogenic and anti-angiogenic treatments have provided new insights into the impact of angiogenesis-based approaches on coronary artery disease. We have recently reported that the hearts of late pregnant (LP) mice are more prone to ischemia/reperfusion (I/R) injury compared to non pregnant(NP) mice. Provided the significant change of angiogenesis status in pregnancy, here we explored whether stimulating the angiogenesis with VEGF is able to protect the heart against I/R injury in late pregnancy, and whether anti-antigenic treatment with soluble endoglin(sENG), an anti-angiogenic factor, aggravates cardiac I/R injury in NP. Pregnant mice at day 12 either received daily injection of VEGF (100 ug/kg daily subcutaneous injection) or PBS(LP CTRL) for 7 days, and at day 19 the LP mice hearts were subjected to 20 min ischemia followed by 40 min reperfusion in Langendorff. NP mice either received a single adenovirus sENG(2х10 8particles via tail vein injection) or vehicle(NP CTRL), and 10 days later NP mice were subjected to 20 min ischemia followed by 40 min reperfusion in Langendorff. The heart function was recorded throughout the experiments, and the infarct size was measured by TTC staining at the end of experiments. Exogenous VEGF treatment significantly improved the cardiac function of LP mice after ischemia. The rate pressure product (RPP) at the end of reperfusion was improved from 1617±287 mmHg*beats/min (n=6) in LP CTRL to 11287±1783 mmHg*beats/min (n=3) in the VEGF group(p<0.01). The infarct size was also significantly reduced by VEGF treatment to 25.0±4.3% (n=3) from 57.4±5.2%(n=6) in CTRL (p<0.01). While sENG aggravated the cardiac I/R injury in NP, as the RPP at the end of reperfusion in the sENG group (4523±1281 mmHg*beats/min, n=4) was significantly lower compared with NP CTRL group(12818±1213 mmHg*beats/min, n=6)(p<0.01). Furthermore, the infarct size in the sENG group was markedly higher compared with NP CTRL group (34.0±3.3% (n=4) vs. 16.3±1.4%(n=6) in NP CTRL, p<0.05). In conclusion, anti-angiogenic treatment aggravates the cardiac I/R injury in NP, while angiogenic therapy protects the heart against I/R injury in LP.


2015 ◽  
Vol 35 (6) ◽  
pp. 2121-2134 ◽  
Author(s):  
Jian-Ying Zhang ◽  
Feng Wu ◽  
Xiao-Ming Gu ◽  
Zhen-Xiao Jin ◽  
Ling-Heng Kong ◽  
...  

Aims: The aim of this study was to determine whether calpain is involved in Cl- -induced myocardial ischemia/reperfusion (I/R) injury. Methods: Isolated rat hearts were subjected to either 45 min of global no-flow ischemia followed by reperfusion or successive perfusion with Ca2+ -free KH solution for 3 min and normal KH solution for 30 min, also known as Ca2+ paradox. Results: The hearts in the I/R group exhibited increases in myocardial injury area, LDH release, caspase 3 activity and apoptotic indices and a marked decline in cardiac performance. As was the case regarding the effects of MDL 28170, an inhibitor of calpain, treatment with 5 µM NPPB, 5 µM DIDS and low Cl- significantly attenuated cardiac injury. Moreover, each of the treatments significantly protected against Ca2+ overload-induced injury in the setting of Ca2+ paradox. The Western blot and immunofluorescence data revealed that there was an increase in the percentages of calpain membrane-positive cells and the numbers of fragments resulting from the calpain-mediated proteolysis of α-fodrin in both the I/R and the Ca2+ paradox, indicating that the activation of calpain occurred. More importantly, these effects were mitigated by the blockade of transmembrane Cl- flux, as was accomplished via MDL 28170. Conclusion: Our results provide evidence that the blockade of transmembrane Cl- flux mitigates I/R-induced cardiac injury via the inhibition of calpain activity. They also indicate that intracellular Ca2+ overload regulates calpain activation in the setting of Cl- -induced injury.


Author(s):  
Yuika Osada ◽  
Shunsaku Nakagawa ◽  
Kanako Ishibe ◽  
Shota Takao ◽  
Aimi Shimazaki ◽  
...  

Recent studies have revealed the impact of antibiotic-induced microbiome depletion (AIMD) on host glucose homeostasis. The kidney has a critical role in systemic glucose homeostasis; however, information regarding the association between AIMD and renal glucose metabolism remains limited. Hence, we aimed to determine the effects of AIMD on renal glucose metabolism by inducing gut microbiome depletion using an antibiotic cocktail (ABX) composed of ampicillin, vancomycin, and levofloxacin in mice. The results showed that the bacterial 16s rRNA expression, luminal concentrations of short-chain fatty acids and bile acids, and plasma glucose levels were significantly lower in ABX-treated mice than in vehicle-treated mice. In addition, ABX treatment significantly reduced renal glucose and pyruvate levels. The mRNA expression levels of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase in the renal cortex were significantly higher in ABX-treated mice than in vehicle-treated mice. We further examined the impact of AIMD on the altered metabolic status in mice after ischemia-induced kidney injury. After exposure to ischemia for 60 min, the renal pyruvate concentrations were significantly lower in ABX-treated mice than in vehicle-treated mice. ABX treatment caused a more severe tubular injury after ischemia-reperfusion (IR). Our findings confirm that AIMD is associated with decreased pyruvate levels in the kidney, which may have been caused by the activation of renal gluconeogenesis. Thus, we hypothesized that AIMD would increase the vulnerability of the kidney to IR injury.


2021 ◽  
Vol 129 (Suppl_1) ◽  
Author(s):  
Alexander S Milliken ◽  
Sergiy M Nadtochiy ◽  
Paul S Brookes

Succinate is a metabolite that plays a central role in ischemia-reperfusion (IR) injury,which is relevant to myocardial infarction (heart attack) and stroke. Succinateaccumulates during ischemia and is rapidly consumed at reperfusion driving reactiveoxygen species (ROS) generation at complex-I (Cx-I) and III of the mitochondrial electrontransport chain. This ROS production triggers cell-death, leading to tissue necrosis.Although succinate oxidation has been extensively studied and exploited as a noveltherapeutic target, only 1/3 of the succinate accumulated in ischemia is oxidized atreperfusion, with the remaining 2/3 being released from the cell via monocarboxylatetransporter 1 (MCT1). Extracellular succinate is thought to be pro-inflammatory, and ithas been proposed that preventing succinate release may be therapeutically beneficial.To determine the impact of preventing succinate release on IR injury, we comparedfunctional recovery (i.e. rate x pressure product, RPP) and infarction (i.e. tissue necrosis)of Langendorff perfused mouse hearts treated with an MCT1 inhibitor, AR-C155858,versus vehicle control. This revealed that succinate retention worsens IR injury (i.e.increased infarction and decreased functional recovery) likely due to increased ROS. Totest this hypothesis, we utilized a Langendorff apparatus positioned within aspectrofluorimeter, which permits real-time fluorescence measurements in beatingmouse hearts. Using the mitochondria targeted superoxide probe, MitoSOX red tomeasure ROS production at reperfusion + AR-C155858, demonstrated that succinateretention leads to enhanced mitochondrial ROS generation at the onset of reperfusion.Overall, these results suggest that inhibiting succinate release in the context of IR injurymay not be a viable therapeutic approach, regardless of any downstream anti-inflammatory effects.


Sign in / Sign up

Export Citation Format

Share Document