Attenuated Cell Apoptosis Research Articles

The alkaloids of Corydalis hendersonii Hemsl. contribute to the cardioprotective effect against ischemic injury in mice by attenuating cardiomyocyte apoptosis via p38 MAPK signaling pathway

BackgroundThere is a characteristic Tibetan folk medicine in China named Corydalis hendersonii Hemsl. (CH) has been used for treatment of cardiovascular related diseases, called “plethora” in Tibetan medicine. Previous studies demonstrated that ethanol extract of CH showed anti-acute myocardial infarction (AMI) effect through inhibiting fibrosis and inflammation. Rich alkaloids fraction (RAF) is isolated from CH, but whether RAF possessing an equivalent effect with the CH ethanol extract and by which mechanism it protects against AMI has not yet reported. The paper aimed to study the potential role of RAF on myocardial injured mice and its underlying mechanism.Materials and methodsLiquid chromatography mass spectrometry-ion trap-time of flight (LCMS-IT-TOF) was used to analyze the chemical profile and isolate pure compounds. The ligation of left anterior descending (LAD) of coronary artery in mice was used to evaluate the in vivo anti-AMI effect, by dividing into eight groups: Sham, Model, Fosinopril (10 mg/kg, i.g.), total extract (TE, 400 mg/kg, i.g.), poor alkaloids fraction (PAF, 300 mg/kg, i.g.), and RAF (25, 50, and 100 mg/kg, respectively, i.g.) groups. Echocardiography was used to evaluate mice heart function through the index of left ventricular end-systolic diameter (LVEDs), left ventricular end-diastolic diameter (LVEDd), fractional shortening (FS) and ejection fraction (EF). We detected the lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) in the serum and the plasma level of angiotensin II (AngII). The apoptosis of mice myocardial tissue was verified by TUNEL assay. The expression of p38 mitogen-activated protein kinases (p38 MAPK), Bcl-2 and Bcl-2-associated X protein (Bax) were detected through immunofluorescence staining, qRT-PCR and western blot in mice heart tissue and H9c2 cells.ResultsEchocardiography data indicated that the values of LVEDd and LVEDs were reduced and the values of FS and EF were improved by TE and RAF significantly. RAF also decreased the levels of LDH, CK-MB and AngII and significantly inhibited inflammatory cells in the marginal zone of myocardial infarction. The TUNEL assay results showed that RAF significantly attenuated cell apoptosis. Immunofluorescence and qRT-PCR assay showed that RAF inhibited p38 MAPK, Bax, and Bcl-2 proteins in mice myocardium. Western blot results validated that the expressions of key proteins were inhibited by RAF. Also, the apoptotic cells and apoptosis-related proteins were dramatically reduced by RAF in vivo and in vitro. Besides, RAF and PAF were analyzed by LCMS-IT-TOF to identify the main compounds and to demonstrate the difference between them. The results showed that a total of 14 alkaloids were identified, which indicated that the isoquinoline alkaloids were the main ingredients in RAF may contributing to the cardioprotective effect in mice.ConclusionsRAF improves cardiac function by inhibiting apoptosis via p38 MAPK signaling pathway, and RAF contributes to the effect against myocardial ischemic injury of TE in mice, which provides a substantial reference for the clinical application against ischemia heart disease and quality control of CH.Graphical

Trehalose attenuates abdominal aortic aneurysm formation by inducing autophagy in smooth muscle cells.

Trehalose is a naturally occurring disaccharide, which has been identified as an autophagy inducer and exhibits protective effect in cardiovascular diseases such as myocardial infraction and atherosclerosis. However, the functional role of trehalose in abdominal aortic aneurysm (AAA) remains undefined. To study the effect of trehalose in AAA, trehalose (1 g/kg per day) were given for 14 continuous days in a mouse model of elastase-induced abdominal aortic aneurysm. On day 14, ultrasound was performed to measure aortic diameter before the abdominal aortas were harvested and processed for further analysis. Verhoeff-Van Gieson staining and TUNEL staining were performed on paraffin sections to evaluate vascular histology and apoptosis, immunofluorescence staining and Western-blot were performed to evaluate expression of autophagy markers. Echocardiography and in situ pictures demonstrated that trehalose attenuated infrarenal aorta dilation. Verhoeff-Van Gieson staining showed elastin degradation was improved in trehalose-treated group. Compared with vehicle-treated mice, trehalose treatment restored smooth muscle cell contractile phenotype with increased α-SMA, Calponin and Myh11 expression. Furthermore, trehalose also attenuated cell apoptosis and leukocytes infiltration. Importantly, trehalose induced autophagy with decrease SQSTM1/p62 accumulation, increased lamp2 expression and LC3B conversion. Trehalose attenuated AAA progression with decreased inflammation and restored SMC contractile phenotype by inducing autophagy. These results demonstrated the therapeutic potential of trehalose in AAA.

Downregulation of mitochondrial calcium uptake family 3 attenuates secondary brain injury after intracerebral hemorrhage in rats.

Intracerebral hemorrhage (ICH) is one type of stroke with a high incidence and mortality. Mitochondria provide energy for various life processes and regulate calcium-mediated signaling pathways by taking up calcium ions from cytoplasm. Mitochondrial calcium uptake family 3 (MICU3) is a tissue-specific enhancer of mitochondrial calcium uptake. The effects and mechanisms of MICU3 in ICH are unknown. In this study, we aimed to explore the role of MICU3 in ICH in rats and neuronal models. First, we constructed ICH model both in vivo and in vitro and observed increased expression of MICU3. Then lentivirus was transduced to knock down MICU3. We observed that knockdown of MICU3 significantly reduced mitochondrial uptake of calcium in primary neurons. Moreover, the downregulation of MICU3 attenuated cell apoptosis and decreased the accumulation of reactive oxygen species (ROS). Recovery of neurobehavioral and cognitive function also benefited from downregulation of MICU3. The findings demonstrated that MICU3 played an important role in cell apoptosis, oxidative stress, and maintenance of mitochondrial structure and function, and promoted rehabilitation of neurobehavior. In conclusion, MICU3 is expected to be a molecular marker and a potential therapeutic target for ICH.

Human Pluripotent Stem Cell-Mesenchymal Stem Cell-Derived Exosomes Promote Ovarian Granulosa Cell Proliferation and Attenuate Cell Apoptosis Induced by Cyclophosphamide in a POI-like Mouse Model.

Premature ovarian insufficiency (POI) is a complex disease which causes amenorrhea, hypergonadotropism and infertility in patients no more than 40 years old. Recently, several studies have reported that exosomes have the potential to protect ovarian function using a POI-like mouse model induced by chemotherapy drugs. In this study, the therapeutic potential of exosomes derived from human pluripotent stem cell-mesenchymal stem cells (hiMSC exosomes) was evaluated through a cyclophosphamide (CTX)-induced POI-like mouse model. POI-like pathological changes in mice were determined by serum sex-hormones levels and the available number of ovarian follicles. The expression levels of cellular proliferation proteins and apoptosis-related proteins in mouse ovarian granulosa cells were measured using immunofluorescence, immunohistochemistry and Western blotting. Notably, a positive effect on the preservation of ovarian function was evidenced, since the loss of follicles in the POI-like mouse ovaries was slowed. Additionally, hiMSC exosomes not only restored the levels of serum sex hormones, but also significantly promoted the proliferation of granulosa cells and inhibited cell apoptosis. The current study suggests that the administration of hiMSC exosomes in the ovaries can preserve female-mouse fertility.

Apigenin alleviates oxidative stress-induced myocardial injury by regulating SIRT1 signaling pathway

Apigenin is a natural flavonoid which is widely found in vegetables and fruits. However, the mechanism of apigenin in oxidative stress-induced myocardial injury has not been fully elucidated. We established an isoproterenol (Iso)-induced myocardial injury mouse model and a hypoxia/reoxygenation (H/R)-induced H9c2 cell injury model, followed by pretreatment with apigenin to explore its protective effects. Apigenin can significantly alleviate isoproterenol-induced oxidative stress, cell apoptosis and myocardial remodeling in vivo. Apigenin pretreatment can also significantly improve cardiomyocyte morphology, decrease H/R induced oxidative stress, and attenuate cell apoptosis and inflammation in vitro. Further mechanism study revealed that apigenin treatment reversed isoprenaline and H/R-induced decrease of Sirtuin1 (SIRT1). Molecular docking results proved that apigenin can form hydrogen bond with 230 Glu, a key site of SIRT1 activation, indicating that apigenin is an agonist of SIRT1. Moreover, SIRT1 knockdown by siRNA significantly reversed the protective effect of apigenin in H/R-induced myocardial injury. In conclusion, apigenin protects cardiomyocyte function from oxidative stress-induced myocardial injury by modulating SIRT1 signaling pathway, which provides a new potential therapeutic natural compound for the clinical treatment of cardiovascular diseases.

Forsythiaside A ameliorates sepsis-induced acute kidney injury via anti-inflammation and antiapoptotic effects by regulating endoplasmic reticulum stress

Ethnopharmacological relevanceSepsis is a systemic inflammatory response syndrome caused by an infection in the body, and accompanying acute kidney injury (AKI) is a common complication of sepsis. It is associated with increased mortality and morbidity. Forsythia Fructus, the dried fruit of Forsythia suspensa (Thunb.) Vahl, is a commonly used traditional Chinese medicine.Aims of the studyThis study aimed to elucidate the protective effect of Forsythiaside A (FTA) on sepsis-induced AKI by downregulating inflammatory and apoptotic responses, and exploring its underlying mechanism.MethodsSeptic AKI was induced through intraperitoneal injection of LPS (10 mg/kg) using male C57BL/6 mice and pretreated with FTA or control saline. First, we assessed the degree of renal injury by creatinine, blood urea nitrogen measurement, and HE staining of renal tissue; secondly, the inflammation and apoptosis were measured byELISA, qPCR, and TUNEL immunofluorescence; finally, the mechanism was explored by computer molecular docking and Western blot.ResultsOur data showed that FTA markedly attenuated pathological kidney injuries, alleviated the elevation of serum BUN and Creatinine, suggesting the renal protective effect of FTA. Notably, FTA significantly inhibited the renal expression of proinflammatory cytokine IL-1β, IL-6, and TNF-α both at protein and mRNA levels and attenuated cell apoptosis in the kidney, as measured by caspase-3 immunoblot and TUNEL assay, indicating its anti-Inflammation and antiapoptotic properties. Mechanistically, administration of LPS resulted in robust endoplasmic reticulum (ER) stress responses in the kidney, evidenced by glucose-regulated protein 78(GRP78) upregulation, protein kinase RNA–like endoplasmic reticulum kinase (PERK) activation, eukaryotic initiation factor 2 alpha (elF2α) phosphorylation and C/EBP homologous protein (CHOP) overexpression, which could be significantly blocked by FTA pretreatment. Dynamic simulation and molecular docking were performed to provide further insight.ConclusionsCollectively, our data suggest that FTA ameliorates sepsis-induced acute kidney injury via its anti-inflammation and antiapoptotic properties by regulating PERK signaling dependent ER stress responses.

Ampelopsin induces MDA-MB-231 cell cycle arrest through cyclin B1-mediated PI3K/AKT/mTOR pathway in vitro and in vivo.

Breast cancer is one of the most common malignant tumors in women and it is the most frequently diagnosed cancer in the world. Ampelopsin (AMP) is a purified component from the root of Ampelopsis grossedentata. It is reported that AMP could significantly inhibit the proliferation of breast cancer cells. However, the antitumor mechanism against breast cancer has not yet been fully elucidated. The purpose of this work was to study the role of AMP against breast cancer MDA-MB-231 cells and to further investigate the underlying mechanism. PI3K/AKT/mTOR plays a very important role in tumor cell growth and proliferation and we hypothesize that AMP may inhibit this pathway. In the present work, the results showed that AMP could significantly inhibit the growth of breast cancer MDA-MB-231 cells in vitro and in vivo. In addition, treatment with AMP decreased the levels of PI3K, AKT and mTOR, as well as cyclin B1 expression, followed by p53/p21 pathway activation to arrest the cell cycle at G2/M. Moreover, it demonstrated a positive association between cyclin B1 and PI3K/AKT/mTOR levels. Importantly, this pathway was found to be regulated by cyclin B1 in MDA-MB-231 cells treated with AMP. Also, it was observed that cyclin B1 overexpression attenuated cell apoptosis and weakened the inhibitory effects of AMP on cell proliferation. Together, AMP could inhibit breast cancer MDA-MB-231 cell proliferation in vitro and in vivo, due to cell cycle arrest at G2/M by inactivating PI3K/AKT/mTOR pathway regulated by cyclin B1.

Endoplasmic reticulum stress mediated by ROS participates in cadmium exposure-induced MC3T3-E1 cell apoptosis

Cadmium (Cd), as one of the seventh most toxic heavy metal pollutants, widely persisted in the environment, leading to osteoblast dysfunction and ultimately Cd-related skeletal disease. However, the damaging effects of Cd on cellular functions and the potential pathogenic mechanisms are still unclear. In our study, Cd is believed to induce mitochondrial dysfunction and endoplasmic reticulum stress (ERS) in a dose-dependent manner, thereby leading to apoptosis, as evident by elevated Drp1, Fis1, GRP78, CHOP, ATF4, P-EIF2α, P-PERK, BAX, cleaved caspase 3 proteins expression and ROS levels, and decreased the levels of Mfn2, OPA1, Bcl2, and intracellular Collagen I, B-ALP, RUNX2, and BGP genes. Additionally, when the exogenous addition of NAC and 4-PBA was added, it was found that NAC and 4-PBA had a positive moderating effect on Cd-induced cell dysfunction. Mechanistically, Cd-induced oxidative stress and apoptosis by upregulating the PERK-EIF2α-ATF4-CHOP signaling pathway and inhibiting the Nrf2/NQO1 pathway. In conclusion, we found that Cd was involved in mitochondrial dysfunction, ERS, and apoptosis in MC3T3-E1 cells, While NAC and 4-PBA relieved ERS and attenuated cell apoptosis.

TWEAK Knockdown Alleviates Post-Cardiac Arrest Brain Injury via the p38 MAPK/NF-κB Pathway.

Cardiac arrest (CA) and subsequent cardiopulmonary resuscitation (CPR) can cause brain injury, which is one of the factors affecting the recovery of brain function in CA patients. There is increasing evidence that tumor necrosis factor-like weak apoptosis-inducing factor (TWEAK) is associated with the brain injury diseases. This study was aimed to investigate the modulation mechanism of TWEAK involved in brain injury after cardiac arrest/subsequent cardiopulmonary resuscitation (CA/CPR). For in vivo experiments, healthy male Sprague-Dawley (SD) rats were applied to establish CA/CPR model, and oxygen-glucose deprivation/reoxygenation (OGD/R)-stimulated neurons model was established in vitro. TWEAK short hairpin RNAs (shRNAs) were injected into the lateral ventricle of CA/CPR rats or transfected into OGD/R cell culture to analyze the consequent alteration in neurological scores, behavioral tests, cell proliferation, cell apoptosis, and neuroinflammation through immunofluorescence staining, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) staining and enzyme linked immunosorbent assay (ELISA). There were high expressions of TWEAK and fibroblast growth factor-inducible 14 (Fn14) in the cerebral cortex of CA/CPR rats and OGD/R-stimulated neuronal cells. TWEAK knockdown attenuated cell apoptosis, inflammation and showed better behavioral tests in CA/CPR rats. Furthermore, TWEAK shRNAs obviously facilitated cell proliferation, suppressed apoptosis and inflammation after OGD/R injury. Western blotting results stated that TWEAK silencing promoted phosphorylated p38 (p-p38) and phosphorylated p65 (p-p65) expressions. TWEAK might be involved in the pathogenesis of CA/CPR through inhibiting p38 MAPK/NF-κB pathway.

Therapeutic Effect of Rapamycin on TDP-43-Related Pathogenesis in Ischemic Stroke.

Stroke is a major cause of death and disability across the world, and its detrimental impact should not be underestimated. Therapies are available and effective for ischemic stroke (e.g., thrombolytic recanalization and mechanical thrombectomy); however, there are limitations to therapeutic interventions. Recanalization therapy has developed dramatically, while the use of adjunct neuroprotective agents as complementary therapies remains deficient. Pathological TAR DNA-binding protein (TDP-43) has been identified as a major component of insoluble aggregates in numerous neurodegenerative pathologies, including ALS, FTLD and Alzheimer's disease. Here, we show that increased pathological TDP-43 fractions accompanied by impaired mitochondrial function and increased gliosis were observed in an ischemic stroke rat model, suggesting a pathological role of TDP-43 in ischemic stroke. In ischemic rats administered rapamycin, the insoluble TDP-43 fraction was significantly decreased in the ischemic cortex region, accompanied by a recovery of mitochondrial function, the attenuation of cellular apoptosis, a reduction in infarct areas and improvements in motor defects. Accordingly, our results suggest that rapamycin provides neuroprotective benefits not only by ameliorating pathological TDP-43 levels, but also by reversing mitochondrial function and attenuating cell apoptosis in ischemic stroke.

Loss of pleckstrin homology domain and leucine-rich repeat protein phosphatase 2 has protective effects on high glucose-injured retinal ganglion cells via the effect on the Akt-GSK-3β-Nrf2 pathway.

Pleckstrin homology domain and leucine-rich repeat protein phosphatase 2 (PHLPP2) is linked to various pathological states. However, whether PHLPP2 mediates diabetic retinopathy is unaddressed. This work explored the biological function of PHLPP2 in modulating high glucose (HG)-elicited damage of retinal ganglion cells (RGCs), an in vitro model for studying diabetic retinopathy. Mouse RGCs were treated with HG to establish a cell model. PHLPP2 was silenced by transfecting specific shRNAs targeting PHLPP2. RT-qPCR, immunoblotting, CCK-8 assay, flow cytometry, TUNEL assay, and ELISA were carried out. Significant increases in PHLPP2 levels were observed in cultured RGCs exposed to HG. The severe damages evoked by HG to RGCs were remarkably weakened in PHLPP2-silenced RGCs, including improved cell survival, attenuated cell apoptosis, repressed oxidative stress, and prohibited proinflammatory response. The silencing of PHLPP2 strengthened the activation of Nrf2 in HG-treated RGCs via modulation of the Akt-GSK-3β axis. Interruption of the Akt-GSK-3β axis reversed PHLPP2-silencing-elicited Nrf2 activation. The protective effects of PHLPP2 silencing on HG-induced injury of RGCs were diminished by Nrf2 inhibition. The loss of PHLPP2 was beneficial for HG-injured RGCs through the effect on the Akt-GSK-3β-Nrf2 pathway. This work suggests a possible role of PHLPP2 in diabetic retinopathy.

Long noncoding RNA HOTAIR facilitates pulmonary vascular endothelial cell apoptosis via DNMT1 mediated hypermethylation of Bcl-2 promoter in COPD

BackgroundTo study the regulatory effect of Long non-coding RNA (LncRNA) HOX transcript antisense RNA (HOTAIR) on pulmonary vascular endothelial cell (HPVEC) apoptosis and determine whether the HOTAIR facilitate HPVEC apoptosis via DNMT1 mediated hypermethylation of Bcl-2 promoter in chronic obstructive pulmonary disease (COPD).MethodsLncRNA array was used to measure the differentially expressed lncRNAs in COPD and non-COPD lung tissues. Expression of HOTAIR in COPD patient lungs and cigarette smoke extract (CSE)-induced HPVEC was assessed by qRT-PCR. The location of HOTAIR was determined in COPD patient lungs and HPVEC by RNA in situ hybridization (RNA-ISH). The emphysema mouse model and HOTAIR knockdown mice were each established by inhaling cigarette smoke or intratracheal lentiviral vectors instillation. The dysregulation of DNA methyltransferase enzyme 1 (DNMT1), B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax) and Cleaved-caspase 3 protein expression were detected by Western blotting. HOTAIR, DNMT1, Bcl-2 and Bax mRNA expression were measured by quantitative real-time polymerase chain reaction. TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) assays were used to assess apoptotic ratio in mice and CSE-induced HPVEC. Methylation-specific PCR (MSP) assay was conducted to observe the alterations in the methylation of the Bcl-2 promoter in specimens. RNA pull-down assay was used for analysis of the correlation between HOTAIR and DNMT1.ResultsThe expression levels of the HOTAIR were up-regulated in COPD patient lungs and CSE-induced HPVEC. HPVEC apoptosis with down-regulated Bcl-2 expression, increased promoter methylation, DNMT1, Bax and Cleaved-caspase 3 expression was found in emphysema mouse model and CSE-induced HPVEC. Knockdown HOTAIR can attenuate cell apoptosis and emphysema via DNMT1 mediated hypermethylation of Bcl-2 promoter in mice. In vitro, HOTAIR can aggravate the apoptosis of CSE-exposed HPVEC. DNMT1 was a target of HOTAIR and had a positive correlation with HOTAIR.ConclusionHOTAIR facilitates HPVEC apoptosis via DNMT1 mediated hypermethylation of Bcl-2 promoter in COPD, and attenuating the expression of HOTAIR may be a new therapy to prevent COPD.

Cadmium-induced apoptosis of Leydig cells is mediated by excessive mitochondrial fission and inhibition of mitophagy

Cadmium is one of the environmental and occupational pollutants and its potential adverse effects on human health have given rise to substantial concern. Cadmium causes damage to the male reproductive system via induction of germ-cell apoptosis; however, the underlying mechanism of cadmium-induced reproductive toxicity in Leydig cells remains unclear. In this study, twenty mice were divided randomly into four groups and exposed to CdCl2 at concentrations of 0, 0.5, 1.0 and 2.0 mg/kg/day for four consecutive weeks. Testicular injury, abnormal spermatogenesis and apoptosis of Leydig cells were observed in mice. In order to investigate the mechanism of cadmium-induced apoptosis of Leydig cells, a model of mouse Leydig cell line (i.e. TM3 cells) was subjected to treatment with various concentrations of CdCl2. It was found that mitochondrial function was disrupted by cadmium, which also caused a significant elevation in levels of mitochondrial superoxide and cellular ROS. Furthermore, while cadmium increased the expression of mitochondrial fission proteins (DRP1 and FIS1), it reduced the expression of mitochondrial fusion proteins (OPA1 and MFN1). This led to excessive mitochondrial fission, the release of cytochrome c and apoptosis. Conversely, cadmium-induced accumulation of mitochondrial superoxide was decreased by the inhibition of mitochondrial fission through the use of Mdivi-1 (an inhibitor of DRP1). Mdivi-1 also partially prevented the release of cytochrome c from mitochondria to cytosol and attenuated cell apoptosis. Finally, given the accumulation of LC3II and SQSTM1/p62 and the obstruction of Parkin recruitment into damaged mitochondria in TM3 cells, the autophagosome-lysosome fusion was probably inhibited by cadmium. Overall, these findings suggest that cadmium induces apoptosis of mouse Leydig cells via the induction of excessive mitochondrial fission and inhibition of mitophagy.

KMT2B-dependent RFK transcription activates the TNF-α/NOX2 pathway and enhances ferroptosis caused by myocardial ischemia-reperfusion

Epigenetic regulation such as histone modification is implicated in the pathogenesis of myocardial ischemia/reperfusion injury (MIRI). Lysine-specific methyltransferase 2B (KMT2B) is a histone H3 lysine 4 (H3K4) methyltransferase. This study aims at exploring the role of KMT2B-mediated histone modification in MIRI. Peripheral blood samples were collected from 30 patients with acute myocardial infarction (AMI) and 30 healthy volunteers for analyses of the expression levels of KMT2B, riboflavin kinase (RFK), tumor necrosis factor (TNF)-α, and NADPH oxidase 2 (NOX2). H9C2 cardiomyocytes and Sprague-Dawley rats were utilized for developing in vitro and in vivo models. To evaluate the effects of the aforementioned molecules on cellular damage and MIRI, short hairpin RNAs or overexpression plasmids were introduced into cardiomyocytes for gene silencing or overexpression and also, they were packaged into adenovirus vectors for in vivo interventions. Immunoprecipitation assays were conducted to assess the interactions between KMT2B and RFK and among RFK, NOX2 sub-unit p22phox, and TNF receptor 1-associated death domain protein. KMT2B, RFK, TNF-α, and NOX2 were notably upregulated in AMI patients. KMT2B knockdown resulted in considerably attenuated cell apoptosis and reduced myocardial infarct area. Additionally, the release of pro-inflammatory proteins and ferroptosis were suppressed. Furthermore, KMT2B could promote RFK gene transcription by upregulating H3 methylation levels and consequently activate the TNF-α/NOX2 axis, which was the possible mechanism underlying the role of KMT2B in MIRI. KMT2B motivates MIRI-induced cellular injury and ferroptosis by inducing RFK transcription and mediating the TNF-α/NOX2 axis.

Modified Taohong Siwu decoction improves cardiac function after myocardial ischaemia and reperfusion in rats by promoting endogenous stem cell mobilization and regulating metabolites

Context Taohong Siwu decoction (THSWD) has been shown to promote heart repair in myocardial infarction. Objective To determine the effects of modified THSWD (THSWD plus four ingredients) on myocardial ischaemia and reperfusion (I/R) injury. Materials and methods Sixty Sprague-Dawley rats were randomly divided into the I/R group and three different modified THSWD dose groups (gavage administration, 1.215, 2.43, and 4.86 g, respectively). 2,3,5-Triphenyltetrazolium chloride and Evans blue staining were used to detect the infarct area at 24 h after treatment. The serum biochemical indexes and cell apoptosis were examined to determine myocardial injury. The number of endogenous stem cells, expression of stromal dell derived factor-1 (SDF-1) and stem cell factor (SCF), and cardiac function were measured at 4 weeks. The serum was collected for metabolomic analysis. Results The high-dose modified THSWD group presented a reduced infarction area (decreased by 21.3%), decreased levels of lactate dehydrogenase and creatinine kinase, attenuated cell apoptosis, and enhanced superoxide dismutase activity in early stage I/R compared with other groups. The serum SCF and SDF-1 levels were higher in the high-dose group than in the I/R group. At 4 weeks, the infarct size and collagen content were the lowest, and the ejection fraction and fractional shortening values were the highest in the high-dose group. Moreover, high-dose modified THSWD affected the metabolism of phosphonate and phosphonate, taurine, and hypotaurine. Conclusions Endogenous stem cell mobilization and metabolic regulation were related to the cardioprotection of modified THSWD. We provided a new strategy and direction for the treatment of cardiovascular diseases with traditional Chinese medicine.

Knockdown of PVT1 Exerts Neuroprotective Effects against Ischemic Stroke Injury through Regulation of miR-214/Gpx1 Axis.

Previous studies have reported that lncRNA PVT1 was closely related to ischemic stroke. Here, the role of PVT1 in ischemic stroke and the underlying mechanism were investigated. OGDR-stimulated PC12 cells were used to construct a cell model to mimic ischemic stroke. si-PVT1, miR-214 mimic, inhibitor, or the negative controls were transfected into PC12 cells prior to OGDR treatment. PVT1, miR-214, and Gpx1 expression was measured by qRT-PCR and western blotting assays. Cell proliferation and apoptosis were tested by CCK-8 assay and western blotting. The expression levels of inflammatory factors were determined by ELISA Kit. Results showed that PVT1 was increased significantly in OGDR PC12 cells. PVT1 knockdown significantly enhanced cell viability and attenuated cell apoptosis, ROS generation, and inflammation in OGDR PC12 cells. More importantly, PVT1 or Gpx1 was a target of miR-214. Mechanistically, PVT1 acted as a competing endogenous RNA of miR-214 to regulate the downstream gene Gpx1. In conclusion, PVT1 knockdown attenuated OGDR PC12 cell injury by modulating miR-214/Gpx1 axis. These findings offer a potential novel strategy for ischemic stroke therapy.

Platycodon D-induced A549 Cell Apoptosis through RRM1-Regulated p53/VEGF/ MMP2 Pathway.

Lung cancer is one of the leading causes of cancer-related deaths worldwide. Platycodin D (PD), a major pharmacological constituent from the Chinese medicinal herb named Platycodonis Radix, has shown potent anti-tumor activity. Also, it is reported that PD could inhibit cellular growth in the non-small-cell lung carcinoma (NSCLC) A549 cell line. However, the underlying mechanism is not fully clarified. Cell proliferation was measured by MTT assay. Annexin V and propidium iodide (PI) assay were employed to study the apoptosis effects of PD on A549 cells. Western blot analysis was used to evaluate protein expression. Also, we used a siRNA against p53, as well as a plasmid-based RRM1 over-expression to investigate their functions. It is demonstrated that PD inhibited A549 cell proliferation in a dose- and time-dependent manner. Further investigations showed that PD induced cell apoptosis, which was supported by dose-dependent and time-dependent caspase-3 activation and p53/VEGF/MMP2 pathway regulation. Also, PD demonstrated the inhibition effect of ribonucleotide reductase M1 (RRM1), whose role in various tumors is contradictory. Remarkably, in this work, RRM1 overexpression in A549 cells could have a negative impact on the regulation of the p53/VEGF/MMP2 pathway induced by PD treatment. Note that RRM1 overexpression also attenuated cell apoptosis and inhibition of cell proliferation of A549 treated with PD. The results suggested that PD could inhibit A549 cell proliferation and induce cell apoptosis by regulating p53/VEGF/MMP2 pathway, in which RRM1 plays an important role directly.

Combined treatment of retinoic acid with olfactory ensheathing cells protect gentamicin-induced SGNs damage in the rat cochlea in vitro

Hearing is mainly dependent on the function of hair cells (HCs) and spiral ganglion neurons (SGNs) which damage or loss of them leads to irreversible hearing loss. Olfactory ensheathing cells (OECs) are specialized glia that forms the fascicles of the olfactory nerve by surrounding the olfactory sensory axons. The OECs, as a regenerating part of the nervous system, play a supporting function in axonal regeneration and express a wide range of growth factors. In addition, retinoic acid (RA) enhances the proliferation and differentiation of these cells into the nerve. In the present study, we co-cultured human OECs (hOECs) with cochlear SGNs in order to determine whether hOECs and RA co-treatment can protect the repair process in gentamycin-induced SGNs damage in vitro. For this purpose, cochlear cultures were prepared from P4 Wistar rats, which were randomly appointed to four groups: normal cultivated SGNs (Control), gentamicin-lesioned SGNs culture (Gent), gentamicin-lesioned SGNs culture treated with OECs (Gent + OECs) and gentamicin-lesioned SGNs culture co-treated with OECs and RA (Gent + OEC& RA). The expression of a specific protein in SGNs was examined using immunohistochemical and Western blotting technique. TUNEl staining was used to detect cell apoptosis. Here, we revealed that combined treatment of OECs and RA protect synapsin and Tuj-1 expression in the lesioned SGNs and attenuate cell apoptosis. These findings suggest that RA co-treatment can enhance efficiency of OECs in repair of SGNs damage induced by ototoxic drug.

Dietary supplementation of salidroside alleviates liver lipid metabolism disorder and inflammatory response to promote hepatocyte regeneration via PI3K/AKT/Gsk3-β pathway

Fatty liver hemorrhagic syndrome (FLHS) is a chronic hepatic disease which occurs when there is a disorder in lipid metabolism. FLHS is often observed in caged laying hens and characterized by a decrease in egg production and dramatic increase of mortality. Salidroside (SDS) is an herbal drug which has shown numerous pharmacological activities, such as protecting mitochondrial function, attenuating cell apoptosis and inflammation, and promoting antioxidant defense system. We aimed to determine the therapeutic effects of SDS on FLHS in laying hens and investigate the underlying mechanisms through which SDS operates these functions. We constructed oleic acid (OA)-induced fatty liver model in vitro and high-fat diet-induced FLHS of laying hens in vivo. The results indicated that SDS inhibited OA-induced lipid accumulation in chicken primary hepatocytes, increased hepatocyte activity, elevated the mRNA expression of proliferation related genes PCNA, CDK2, and cyclinD1 and increased the protein levels of PCNA and CDK2 (P < 0.05), as well as decreased the cleavage levels of Caspase-9, Caspase-8, and Caspase-3 and apoptosis in hepatocytes (P < 0.05). Moreover, SDS promoted the phosphorylation levels of PDK1, AKT, and Gsk3-β, while inhibited the PI3K inhibitor (P < 0.05). Additionally, we found that high-fat diet-induced FLHS hens had heavier body weight, liver weight, and abdominal fat weight, and severe steatosis in histology, compared with the control group (Con). However, hens fed with SDS maintained lighter body weight, liver weight, and abdominal fat weight, as well as normal liver without hepatic steatosis. In addition, high-fat diet-induced FLHS hens had high levels of serum total cholesterol (TC), triglyceride (TG), alanine transaminase (ALT), and aspartate aminotransferase (AST) compared to the Con group, however, in the Model+SDS group, the levels of TC, TG, ALT, and AST decreased significantly, whereas the level of superoxide dismutase (SOD) increased significantly (P < 0.05). We also found that SDS significantly decreased the mRNA expression abundance of PPARγ, SCD, and FAS in the liver, as well as increased levels of PPARα and MTTP, and decreased the mRNA expression of TNF-α, IL-1β, IL-6, and IL-8 in the Model+SDS group (P < 0.05). In summary, this study showed that 0.3 mg/mL SDS attenuated ROS generation, inhibited lipid accumulation and hepatocyte apoptosis, and promoted hepatocyte proliferation by targeting the PI3K/AKT/Gsk3-β pathway in OA-induced fatty liver model in vitro, and 20 mg/kg SDS alleviated high-fat-diet-induced hepatic steatosis, oxidative stress, and inflammatory response in laying hens in vivo.

Isorhapontigenin Modulates SOX9/TOLLIP Expression to Attenuate Cell Apoptosis and Oxidative Stress in Paraquat-Induced Acute Kidney Injury.

Paraquat (PQ) is a widely used herbicide but can be lethal to humans. The kidney is vital for PQ elimination; therefore, explorations for therapeutic approaches for PQ-induced acute kidney injury (AKI) are of great significance. Here, the effects of a natural bioactive polyphenol isorhapontigenin (ISO) on PQ-AKI were investigated. In vitro experiments carried out in PQ-intoxicated rat renal tubular epithelial cells (NRK-52E) showed that ISO treatment inhibited PQ-induced cell apoptosis and oxidative stress, which was evidenced by the decreased proapoptotic proteins [cleaved caspase 3/9 and poly (ADP-ribose) polymerase (PARP)], the reduced oxidative stress indicators [reactive oxygen species (ROS), malondialdehyde (MDA), and lactate dehydrogenase (LDH) leakage], and the increased antioxidants [superoxide dismutase (SOD), nuclear factor E2-related factor 2 (NRF2), and oxygenase-1 (HO-1)]. Furthermore, 50 mg/kg ISO pretreatment before PQ administration significantly attenuated PQ-AKI in rats, as manifested by the improved renal tubule damage, the reduced serum and urine markers of kidney injury, and the inhibited cell apoptosis and oxidative stress in the renal cortex. Furthermore, expression of sex-determining region Y box 9 (SOX9) and Toll-interacting protein (TOLLIP) in NRK-52E cells and the renal cortex was significantly upregulated after ISO treatment. Overexpression of SOX9 increased TOLLIP transcription and attenuated PQ-induced apoptosis and oxidative stress, whereas knockdown of SOX9 impaired the protective effects of ISO on NRK-52E cells against PQ toxicity. In conclusion, the present study demonstrated that ISO modulated SOX9/TOLLIP expression to attenuate cell apoptosis and oxidative stress in PQ-AKI, suggesting the potential of ISO in treating PQ-poisoned patients.