This study investigated the effects of total flavonoids of Dracocephalum moldavica(TFDM) on apoptosis in rat H9c2 cells induced by endoplasmic reticulum stress(ERS) established by oxygen-glucose deprivation and reoxygenation(OGD/R) injury and tunicamycin(TM), and explored the potential mechanisms. After successful modeling, the following groups were set in this experiment: control group, model(OGD/R or TM) group, and TFDM low-, medium-, and high-dose groups(12.5, 25, and 50 μg·mL~(-1)). The OGD/R injury model was constructed in vitro. Cell proliferation was assessed using the cell counting kit-8(CCK-8) method. The levels of lactate dehydrogenase(LDH) and creatine kinase MB isoenzyme(CKMB) in the cell supernatant were detected. Western blot was used to assess the expression of ERS-related proteins, including glucose regulatory protein 78(GRP78), C/EBP homologous protein(CHOP), activating transcription factor 6(ATF6), and apoptotic proteins B-cell lymphoma 2(Bcl-2) and Bcl-2-associated X protein(Bax). Apoptosis was detected using the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling(TUNEL) method. In the TM-induced ERS model, Western blot was used to measure the expression of ERS pathway-related proteins GRP78, CHOP, inositol-requiring enzyme 1(IRE1), X-box binding protein 1(XBP1), protein kinase RNA-like endoplasmic reticulum kinase(PERK), eukaryotic initiation factor 2α(eIF2α), ATF6, p-ATF6, and apoptotic proteins Bcl-2, Bax, cysteinyl aspartate specific proteinase-12(caspase-12), and cleaved caspase-12. Gene expression of GRP78, CHOP, PERK, and ATF6 was detected by real-time fluorescence quantitative PCR(RT-qPCR). Apoptosis was again detected using the TUNEL method. The results showed that in the OGD/R model, compared with the control group, the levels of LDH and CKMB in the cell supernatant were significantly increased in the OGD/R group. Compared with the OGD/R group, the levels of LDH and CKMB in the TFDM group were significantly reduced. Western blot results revealed that compared with the control group, the expression of ERS-related proteins and Bax in the OGD/R group was significantly increased, while the expression of Bcl-2 was significantly decreased. Compared with the OGD/R group, the expression of ERS-related proteins and Bax in the TFDM groups was significantly reduced, and the expression of Bcl-2 was significantly increased. TUNEL assay showed that apoptosis was significantly decreased after TFDM treatment. In the TM-induced ERS experiment, compared with the control group, the expression of ERS-related genes, ERS-related proteins, and apoptotic proteins in the TM group was significantly increased, while the expression of Bcl-2 was significantly decreased. Compared with the TM group, the expression of ERS-related genes, ERS-related proteins, and apoptotic proteins in the TFDM group was significantly reduced, and the expression of Bcl-2 was significantly increased. These results suggest that ERS exists in the OGD/R-injured H9c2 cell model, and TFDM can effectively inhibit ERS-induced apoptosis. The mechanism may be related to the downregulation of ERS pathway-related proteins and apoptotic proteins.
Animals ; Endoplasmic Reticulum Stress/drug effects* ; Apoptosis/drug effects* ; Rats ; Flavonoids/pharmacology* ; Glucose/metabolism* ; Cell Line ; Lamiaceae/chemistry* ; Drugs, Chinese Herbal/pharmacology* ; Oxygen/metabolism* ; Reperfusion Injury/physiopathology* ; Myocytes, Cardiac/cytology*

This study aims to elucidate the role and mechanism of clematichinenoside AR(CAR) in protecting bone marrow mesenchymal stem cells(BMSCs) from hypoxia-induced apoptosis. BMSCs were isolated by the bone fragment method and identified by flow cytometry. Cells were cultured under normal conditions(37℃, 5% CO_2) and hypoxic conditions(37℃, 90% N_2, 5% CO_2) and treated with CAR. The BMSCs were classified into eight groups: control(normal conditions), CAR(normal conditions + CAR), hypoxia 24 h, hypoxia 24 h + CAR, hypoxia 48 h, hypoxia 48 h + CAR, hypoxia 72 h, and hypoxia 72 h + CAR. The cell counting kit-8(CCK-8) assay and terminal-deoxynucleoitidyl transferase mediated nick end labeling(TUNEL) were employed to measure cell proliferation and apoptosis, respectively. The number of mitochondria and mitochondrial membrane potential were measured by MitoTracker®Red CM-H2XRo staining and JC-1 staining, respectively. The level of reactive oxygen species(ROS) was measured with the DCFH-DA fluorescence probe. The protein levels of B-cell lymphoma-2 associated X protein(BAX), caspase-3, and optic atrophy 1(OPA1) were determined by Western blot. The results demonstrated that CAR significantly increased cell proliferation. Compared with the control group, the hypoxia groups showed increased apoptosis rates, reduced mitochondria, elevated ROS levels, decreased mitochondrial membrane potential, upregulated expression of BAX and caspase-3, and downregulated expression of OPA1. In comparison to the corresponding hypoxia groups, CAR intervention significantly decreased the apoptosis rate, increased mitochondria, reduced ROS levels, elevated mitochondrial membrane potential, downregulated the expression of BAX and caspase-3, and upregulated the expression of OPA1. Therefore, it can be concluded that CAR may exert an anti-apoptotic effect on BMSCs under hypoxic conditions by regulating OPA1 to maintain mitochondrial homeostasis.
Mesenchymal Stem Cells/metabolism* ; Apoptosis/drug effects* ; Mitochondria/metabolism* ; Animals ; Rats ; Cell Hypoxia/drug effects* ; Homeostasis/drug effects* ; Reactive Oxygen Species/metabolism* ; Rats, Sprague-Dawley ; Membrane Potential, Mitochondrial/drug effects* ; Saponins/pharmacology* ; Caspase 3/genetics* ; Male ; bcl-2-Associated X Protein/genetics* ; Bone Marrow Cells/metabolism* ; Cell Proliferation/drug effects* ; Protective Agents/pharmacology* ; Cells, Cultured

This paper explored the specific mechanism of ginsenoside Rg_1 in regulating mitochondrial fusion through the neurogenic gene Notch homologous protein 1(Notch1) pathway to alleviate hypoxia/reoxygenation(H/R) injury in HL-1 cells. The relative viability of HL-1 cells after six hours of hypoxia and two hours of reoxygenation was detected by cell counting kit-8(CCK-8). The lactate dehydrogenase(LDH) activity in the cell supernatant was detected by the lactate substrate method. The content of adenosine triphosphate(ATP) was detected by the luciferin method. Fluorescence probes were used to detect intracellular reactive oxygen species(Cyto-ROS) levels and mitochondrial membrane potential(ΔΨ_m). Mito-Tracker and Actin were co-imaged to detect the number of mitochondria in cells. Fluorescence quantitative polymerase chain reaction and Western blot were used to detect the mRNA and protein expression levels of Notch1, mitochondrial fusion protein 2(Mfn2), and mitochondrial fusion protein 1(Mfn1). The results showed that compared with that of the control group, the cell activity of the model group decreased, and the LDH released into the cell culture supernatant increased. The level of Cyto-ROS increased, and the content of ATP decreased. Compared with that of the model group, the cell activity of the ginsenoside Rg_1 group increased, and the LDH released into the cell culture supernatant decreased. The level of Cyto-ROS decreased, and the ATP content increased. Ginsenoside Rg_1 elevated ΔΨ_m and increased mitochondrial quantity in HL-1 cells with H/R injury and had good protection for mitochondria. After H/R injury, the mRNA and protein expression levels of Notch1 and Mfn1 decreased, while the mRNA and protein expression levels of Mfn2 increased. Ginsenoside Rg_1 increased the mRNA and protein levels of Notch1 and Mfn1, and decreased the mRNA and protein levels of Mfn2. Silencing Notch1 inhibited the action of ginsenoside Rg_1, decreased the mRNA and protein levels of Notch1 and Mfn1, and increased the mRNA and protein levels of Mfn2. In summary, ginsenoside Rg_1 regulated mitochondrial fusion through the Notch1 pathway to alleviate H/R injury in HL-1 cells.
Ginsenosides/pharmacology* ; Receptor, Notch1/genetics* ; Signal Transduction/drug effects* ; Mice ; Animals ; Mitochondrial Dynamics/drug effects* ; Mitochondria/metabolism* ; Cell Line ; Reactive Oxygen Species/metabolism* ; Oxygen/metabolism* ; Cell Hypoxia/drug effects* ; Cell Survival/drug effects* ; Membrane Potential, Mitochondrial/drug effects* ; Humans

To study the therapeutic effect and mechanisms of ethyl syringate(MD) on ulcerative colitis(UC), the MTT assay was used to detect the proliferation inhibition of RAW264.7 cells and HT-29 cells by different concentrations of MD(50, 100, 200, 400 μmol·L~(-1)). UC cell models were constructed by inducing RAW264.7 cells and HT-29 cells with lipopolysaccharide(LPS) and tumor necrosis factor-α(TNF-α). An animal model was established by inducing mice with 2.5% dextran sulfate sodium(DSS) to verify the therapeutic effect of MD on UC. A control group, a model group(LPS or TNF-α), and groups treated with different concentrations of MD(50, 100, 200, 400 μmol·L~(-1)) were set up in this study. Nitric oxide(NO) levels were measured using a NO detection kit. Intracellular reactive oxygen species(ROS) levels were assessed using a laser confocal microscope and ROS kit. Enzyme-linked immunosorbent assay(ELISA) was used to detect changes in the levels of interleukin-6(IL-6), TNF-α, interferon-γ(INF-γ), interleukin-10(IL-10), and myeloperoxidase(MPO) in cells and animal tissues. Western blot was used to detect the expression levels of phosphorylated Janus kinase 2(p-JAK2), Janus kinase 2(JAK2), phosphorylated signal transducer and activator of transcription 3(p-STAT3), signal transducer and activator of transcription 3(STAT3), zonula occludens-1(ZO-1), occludin, and claudin-1 in cells and animal tissues. The results showed that MD can improve the inflammatory response by inhibiting the production of NO and ROS and regulating the expression of inflammatory factors. It significantly reduced the disease activity index(DAI) in mice, improved the shortening of the colon, and repaired intestinal epithelial damage by inhibiting the activation of the JAK2/STAT3 pathway, thereby exerting anti-UC activity.
Animals ; Colitis, Ulcerative/chemically induced* ; Janus Kinase 2/genetics* ; STAT3 Transcription Factor/genetics* ; Mice ; Humans ; Signal Transduction/drug effects* ; Male ; RAW 264.7 Cells ; Reactive Oxygen Species/metabolism* ; Nitric Oxide/metabolism* ; HT29 Cells ; Salicylates/administration & dosage* ; Protective Agents/administration & dosage*

This article investigated the effect and mechanism of salidroside(SAL) on the expression of adhesion molecules in oxidized low-density lipoprotein(oxLDL)-induced mouse aortic endothelial cell(MAEC). The oxLDL-induced endothelial cell injury model was constructed, and the safe concentration and action time of SAL were screened. The cells were divided into control group, oxLDL group, low and high concentration groups of SAL, and ferrostatin-1(Fer-1) group. The cell viability was detected by CCK-8 assay; lactate dehydrogenase(LDH) leakage was measured by colorimetry; the expression of intercellular adhesion molecule 1(ICAM-1) and recombinant vascular cell adhesion molecule 1(VCAM-1) were detected by immunofluorescence; Fe~(2+),glutathione(GSH),malondialdehyde(MDA),and 4-hydroxynonenal(4-HNE) levels were detected by kit method; reactive oxygen species(ROS) was detected by DCFH-DA probe; the levels of glutathione peroxidase 4(GPX4),silent mating type information regulation 2 homolog 1(SIRT1), and nuclear factor erythroid 2-related factor 2(Nrf2) were determined by using Western blot. The inhibitors of Nrf2 and SIRT1 were used, and endothelial cell were divided into control group, oxLDL group, SAL group, ML385 group(Nrf2 inhibitor), and EX527 group(SIRT1 inhibitor). The ultrastructure of mitochondria was observed by electron microscope; mitochondrial membrane potential(MMP) was detected by flowcytometry; the expressions of SIRT1,Nrf2,solute carrier family 7 member 11(SLC7A11),GPX4,ferroportin 1(FPN1),ferritin heavy chain 1(FTH1),ICAM-1, and VCAM-1 were detected by Western blot. The results showed that similar to Fer-1,low and high concentrations of SAL could improve cell viability, inhibit LDH release and the expression of ICAM-1 and VCAM-1 in oxLDL-induced endothelial cells(P<0.05 or P<0.01). It was related to increase in GSH level, decrease in Fe~(2+),ROS,MDA, and 4-HNE level, and up-regulation of SIRT1,Nrf2, and GPX4 expression to inhibit ferroptosis(P<0.05 or P<0.01). The intervention effect of high concentration SAL was the most significant. ML385 and EX527 could partially offset the protection of SAL on mitochondrial structure and MMP and reverse the ability of SAL to up-regulate the expression of SIRT1,Nrf2,SLC7A11,GPX4,FPN1, and FTH1 and down-regulate the expression of ICAM-1 and VCAM-1(P<0.05 or P<0.01).To sum up, SAL could reduce the expression of ICAM-1 and VCAM-1 in oxLDL-induced endothelial cell, which may relate to activation of SLC7A11/GPX4 antioxidant signaling pathway mediated by SITR1/Nrf2, up-regulation of FPN1 and FTH1 expression, and inhibition of ferroptosis.
Sirtuin 1/genetics* ; Animals ; Ferroptosis/drug effects* ; Lipoproteins, LDL/metabolism* ; NF-E2-Related Factor 2/genetics* ; Mice ; Endothelial Cells/cytology* ; Glucosides/pharmacology* ; Phenols/pharmacology* ; Cell Adhesion Molecules/genetics* ; Reactive Oxygen Species/metabolism* ; Intercellular Adhesion Molecule-1/genetics* ; Vascular Cell Adhesion Molecule-1/genetics* ; Cell Survival/drug effects*

This study aims to explore the mechanism of Buyang Huanwu Decoction(BHD) in promoting angiogenesis after oxygen-glucose deprivation/reoxygenation(OGD/R) of mouse brain microvascular endothelial cell line(brain-derived Endothelial cells.3, bEnd.3) based on the caveolin-1(Cav1)/Yes-associated protein 1(YAP1)/hypoxia-inducible factor-1α(HIF-1α) signaling pathway. Ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry(UPLC-Q-TOF-MS) was used to analyze the blood components of BHD. The cell counting kit-8(CCK-8) method was used to detect the optimal intervention concentration of drug-containing serum of BHD after OGD/R injury of bEnd.3. The lentiviral transfection method was used to construct a Cav1 silent stable strain, and Western blot and polymerase chain reaction(PCR) methods were used to verify the silencing efficiency. The control bEnd.3 cells were divided into a normal group(sh-NC control group), an OGD/R model + blank serum group(sh-NC OGD/R group), and an OGD/R model + drug-containing serum group(sh-NC BHD group). Cav1 silent cells were divided into an OGD/R model + blank serum group(sh-Cav1 OGD/R group) and an OGD/R model + drug-containing serum group(sh-Cav1 BHD group). The cell survival rate was detected by the CCK-8 method. The cell migration ability was detected by a cell migration assay. The lumen formation ability was detected by an angiogenesis assay. The apoptosis rate was detected by flow cytometry, and the expression of YAP1/HIF-1α signaling pathway-related proteins in each group was detected by Western blot. Finally, co-immunoprecipitation was used to verify the interaction between YAP1 and HIF-1α. The results showed astragaloside Ⅳ, formononetin, ferulic acid, and albiflorin in BHD can all enter the blood. The drug-containing serum of BHD at a mass fraction of 10% may be the optimal intervention concentration for OGD/R-induced injury of bEnd.3 cells. Compared with the sh-NC control group, the sh-NC OGD/R group showed significantly decreased cell survival rate, cell migration rate, mesh number, node number, and lumen length, significantly increased cell apoptotic rate, significantly lowered phosphorylation level of YAP1 at S127 site, and significantly elevated nuclear displacement level of YAP1 and protein expression of HIF-1α, vascular endothelial growth factor(VEGF), and vascular endothelial growth factor receptor 2(VEGFR2). Compared with the same type of OGD/R group, the sh-NC BHD group and sh-Cav1 BHD group had significantly increased cell survival rate, cell migration rate, mesh number, node number, and lumen length, a significantly decreased cell apoptotic rate, a further decreased phosphorylation level of YAP1 at S127 site, and significantly increased nuclear displacement level of YAP1 and protein expression of HIF-1α, VEGF, and VEGFR2. Compared with the sh-NC OGD/R group, the sh-Cav1 OGD/R group exhibited significantly decreased cell survival rate, cell migration rate, mesh number, node number, and lumen length, a significantly increased cell apoptotic rate, a significantly increased phosphorylation level of YAP1 at S127 site, and significantly decreased nuclear displacement level of YAP1 and protein expression of HIF-1α, VEGF, and VEGFR2. Compared with the sh-NC BHD group, the sh-Cav1 BHD group showed significantly decreased cell survival rate, cell migration rate, mesh number, node number, and lumen length, a significantly increased cell apoptotic rate, a significantly increased phosphorylation level of YAP1 at the S127 site, and significantly decreased nuclear displacement level of YAP1 and protein expression of HIF-1α, VEGF, and VEGFR2. YAP1 protein was present in the protein complex precipitated by the HIF-1α antibody, and HIF-1α protein was also present in the protein complex precipitated by the YAP1 antibody. The results confirmed that the drug-containing serum of BHD can increase the activity of YAP1/HIF-1α pathway in bEnd.3 cells damaged by OGD/R through Cav1 and promote angiogenesis in vitro.
Drugs, Chinese Herbal/pharmacology* ; Animals ; Mice ; Signal Transduction/drug effects* ; Glucose/metabolism* ; Caveolin 1/genetics* ; Hypoxia-Inducible Factor 1, alpha Subunit/genetics* ; YAP-Signaling Proteins ; Oxygen/metabolism* ; Endothelial Cells/metabolism* ; Cell Line ; Adaptor Proteins, Signal Transducing/genetics* ; Neovascularization, Physiologic/drug effects* ; Cell Hypoxia/drug effects* ; Angiogenesis

This study aims to explore the effects and action mechanisms of the active ingredients in Buyang Huanwu Decoction(BYHWD), namely tetramethylpyrazine(TMP) and hydroxy-safflor yellow A(HSYA), on oxygen-glucose deprivation/reglucose-reoxygenation(OGD/R)-induced inflammation and oxidative stress of microglia(MG). Network pharmacology was used to screen the effective monomer ingredients of BYHWD and determine the safe concentration range for each component. Inflammation and oxidative stress models were established to further screen the best ingredient combination and optimal concentration ratio with the most effective anti-inflammatory and antioxidant effects. OGD/R BV2 cell models were constructed, and BV2 cells in the logarithmic growth phase were divided into a normal group, a model group, an HSYA group, a TMP group, and an HSYA + TMP group. Enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of inflammatory cytokines such as interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), and interleukin-6(IL-6). Oxidative stress markers, including superoxide dismutase(SOD), nitric oxide(NO), and malondialdehyde(MDA), were also measured. Western blot was used to analyze the protein expression of both inflammation-related pathway [Toll-like receptor 4(TLR4)/nuclear factor-kappa B(NF-κB)] and oxidative stress-related pathway [nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)]. Immunofluorescence was used to assess the expression of proteins such as inducible nitric oxide synthase(iNOS) and arginase-1(Arg-1). The most effective ingredients for anti-inflammatory and antioxidant effects in BYHWD were TMP and HSYA. Compared to the normal group, the model group showed significantly increased levels of IL-1β, TNF-α, IL-6, NO, and MDA, along with significantly higher protein expression of NF-κB, TLR4, Nrf2, and HO-1 and significantly lower SOD levels. The differences between the two groups were statistically significant. Compared to the model group, both the HSYA group and the TMP group showed significantly reduced levels of IL-1β, TNF-α, IL-6, NO, and MDA, lower expression of NF-κB and TLR4 proteins, higher levels of SOD, and significantly increased protein expression of Nrf2 and HO-1. Additionally, the expression of the M1-type MG marker iNOS was significantly reduced, while the expression of the M2-type MG marker Arg-1 was significantly increased. The results of the HSYA group and the TMP group had statistically significant differences from those of the model group. Compared to the HSYA group and the TMP group, the HSYA + TMP group showed further significant reductions in IL-1β, TNF-α, IL-6, NO, and MDA levels, along with significant reductions in NF-κB and TLR4 protein expression, an increase in SOD levels, and elevated Nrf2 and HO-1 protein expression. Additionally, the expression of the M1-type MG marker iNOS was reduced, while the M2-type MG marker Arg-1 expression increased significantly in the HSYA + TMP group compared to the TMP or HSYA group. The differences in the results were statistically significant between the HSYA + TMP group and the TMP or HSYA group. The findings indicated that the combined use of HSYA and TMP, the active ingredients of BYHWD, can effectively inhibit OGD/R-induced inflammation and oxidative stress of MG, showing superior effects compared to the individual use of either component.
Oxidative Stress/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Animals ; Mice ; Glucose/metabolism* ; Cell Line ; Inflammation/genetics* ; Oxygen/metabolism* ; Pyrazines/pharmacology* ; Microglia/metabolism* ; NF-E2-Related Factor 2/immunology* ; NF-kappa B/immunology* ; Toll-Like Receptor 4/immunology* ; Anti-Inflammatory Agents/pharmacology* ; Humans

OBJECTIVES: To investigate the mechanism through which N-acetylneuraminic acid (Neu5Ac) exacerbates hypoxia/reoxygenation (H/R) injury in rat cardiomyocytes (H9C2 cells). METHODS: H9C2 cells were cultured in hypoxia and glucose deprivation for 8 h followed by reoxygenation for different durations to determine the optimal reoxygenation time. Under the optimal H/R protocol, the cells were treated with 0, 5, 10, 20, 30, 40, 50, and 60 mmol/L Neu5Ac during reoxygenation to explore the optimal drug concentration. The cells were then subjected to H/R injury followed by treatment with Neu5Ac, Fer-1 (a ferroptosis inhibitor), or both. The changes in SOD activity, intracellular Fe²⁺ and lipid ROS levels in the cells were evaluated, and the cellular expressions of Nrf2, GPX4, HO-1, FSP1, and xCT proteins were detected using Western blotting. RESULTS: Following hypoxia and glucose deprivation for 8 h, the cells with reoxygenation for 6 h, as compared with other time lengths of reoxygenation except for 9 h, showed the lowest expression levels of Nrf2, GPX4, HO-1, and FSP1 proteins (P<0.001). Neu5Ac treatment of dose-dependently decreased the viability of the cells with H/R injury with an IC₅₀ of 30.07 mmol/L. Reoxygenation for 3 h with normal glucose supplementation and a Neu5Ac concentration of 30 mmol/L were selected as the optimal conditions in the subsequent experiments. The results showed that Neu5Ac could significantly increase SOD activity, Fe²⁺ and lipid ROS levels and reduce Nrf2, GPX4, HO-1, and FSP1 protein expressions in H9C2 cells with H/R injury, but its effects were significantly attenuated by treatment with Fer-1. CONCLUSIONS Neu5Ac exacerbates ferroptosis of myocardial cells with H/R injury by inhibiting the Nrf2 axis to promote the production of ROS and lipid ROS.
Ferroptosis/drug effects* ; Myocytes, Cardiac/cytology* ; Animals ; NF-E2-Related Factor 2/metabolism* ; Rats ; N-Acetylneuraminic Acid/pharmacology* ; Cell Hypoxia ; Reactive Oxygen Species/metabolism* ; Cell Line ; Myocardial Reperfusion Injury/metabolism*

OBJECTIVES: To investigate the antioxidative mechanism of snake venom-derived protein C activator (PCA) in mitigating vascular endothelial cell injury. METHODS: Human umbilical vein endothelial cells (HUVECs) were cultured in DMEM containing 1.0 g/L D-glucose and exposed to hypoxia (1% O₂) for 6 h followed by reoxygenation for 2 h to establish a cell model of oxygen-glucose deprivation/reoxygenation (OGD/R). The cell model was treated with 2 μg/mL PCA alone or in combination with 2-ME2 (a HIF-1α inhibitor) or DMOG (a HIF-1α stabilizer), and intracellular production of reactive oxygen species (ROS) and protein expression levels of HIF-1α, BNIP3, and Beclin-1 were detected using DCFH-DA fluorescence probe, flow cytometry, and Western blotting. The OGD/R cell model was transfected with a BNIP3-specific siRNA or a scrambled control sequence prior to PCA treatment, and the changes in protein expressions of HIF-1α, BNIP3 and Beclin-1 and intracellular ROS production were examined. RESULTS: In the OGD/R cell model, PCA treatment significantly upregulated HIF-1α, BNIP3 and Beclin-1 expressions and reduced ROS production. The effects of PCA were obviously attenuated by co-treatment with 2-ME2 but augmented by treatment with DMOG (a HIF-1α stabilizer). In the cell model with BNIP3 knockdown, PCA treatment increased BNIP3 expression and decreased ROS production without causing significant changes in HIF-1α expression. Compared with HUVECs with PCA treatment only, the cells with BNIP3 knockdown prior to PCA treatment showed significantly lower Beclin-1 expression and higher ROS levels. CONCLUSIONS Snake venom PCA alleviates OGD/R-induced endothelial cell injury by upregulating HIF-1α/BNIP3 signaling to suppress ROS generation, suggesting its potential as a therapeutic agent against oxidative stress in vascular pathologies.
Humans ; Reactive Oxygen Species/metabolism* ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Human Umbilical Vein Endothelial Cells/drug effects* ; Membrane Proteins/metabolism* ; Proto-Oncogene Proteins/metabolism* ; Up-Regulation ; Cell Hypoxia ; Cells, Cultured ; Snake Venoms/chemistry* ; Beclin-1

OBJECTIVE: To observe the effect of electroacupuncture (EA) pretreatment of "biaoben acupoint combination" on cardiomyocyte mitochondrial fission in the rats with myocardial ischemia-reperfusion injury (MIRI) and explore its mechanism. METHODS: Fifty male SD rats were randomly divided into a sham-operation group, a model group, an EA pretreatment group, an EA pretreatment + Compound C group and an EA pretreatment+ML385 group, 10 rats in each group. In the EA pretreatment, the EA pretreatment + Compound C group and the EA pretreatment+ML385 group, EA was delivered at bilateral "Neiguan" (PC6), "Zusanli" (ST36) and "Guanyuan" (CV4) for 20 min, with continuous wave and 2 Hz of frequency, 1 mA of current, once daily for consecutive 7 days. On day 8, in the EA pretreatment + Compound C group and the EA pretreatment+ML385 group, 30 min before model preparation, the intraperitoneal injection with Compound C (0.3 mg/kg) and ML385 (30 mg/kg) was administered respectively. Except in the sham-operation group, the ligation of the left anterior descending coronary artery was performed to prepare MIRI rat model in the rest groups. In the sham-operation group, the thread was not ligated. After modeling, the content of reactive oxygen species (ROS) in the ischemic area was measured by flow cytometry, superoxide dismutase (SOD) was detected using xanthine oxidase method, and malondialdelyde (MDA) was detected using thiobarbituric acid (TBA) chromatometry. The morphology of myocardial tissue in the ischemic area was observed with HE staining, and the mitochondria ultrastructure of cardiomyocytes observed under transmission electron microscopy. Using immunofluorescence analysis, the positive expression of mitochondrial fission factor (MFF), mitochondrial fission 1 protein antibody (Fis1) and dynamin-related protein 1 (Drp1) was detected; and with immunohistochemical method used, the protein expression of adenosine monophosphate-activated protein kinase (AMPK), nuclear factor E2-associated factor2 (Nrf2) and Drp1 in the ischemic area was detected. RESULTS: Compared with the sham-operation group, the content of ROS and MDA in the myocardial tissue of the ischemic area, and the positive expression of MFF, Fis1 and Drp1 increased in the model group (P<0.01); the content of SOD and the protein expression of AMRK and Nrf2 decreased (P<0.01), and the protein expression of Drp1 elevated (P<0.01). Compared with the model group, the content of ROS and MDA in the myocardial tissue of the ischemic area, and the positive expression of MFF, Fis1 and Drp1 were dropped in the EA pretreatment group (P<0.01); the content of SOD and the protein expression of AMRK and Nrf2 rose (P<0.01), and the protein expression of Drp1 declined (P<0.01); and in the EA pretreatment+Compound C group and the EA pretreatment+ML385 group, the positive expression of MFF, Fis1 and Drp1, and the protein expression of Drp1 were all reduced (P<0.01). When compared with the EA pretreatment + Compound C group and the EA pretreatment+ML385 group, the content of ROS and MDA in the myocardial tissue of the ischemic area, and the positive expression of MFF, Fis1 and Drp1 were dropped in the EA pretreatment group (P<0.01); the content of SOD and the protein expression of AMRK and Nrf2 rose (P<0.01, P<0.05), and the protein expression of Drp1 decreased (P<0.05). In comparison with the model group, the EA pretreatment+Compound C group and the EA pretreatment+ML385 group, the cardiac muscle fiber rupture, cell swelling and mitochondrial disorders were obviously alleviated in the EA pretreatment group. The morphological changes were similar among the model group, the EA pretreatment+Compound C group and the EA pretreatment+ML385 group. CONCLUSION Electroacupuncture pretreatment of "biaoben acupoint combination" attenuates myocardial injury in MIRI rats, probably through promoting the phosphorylation of AMPK and Nrf2, inhibiting the excessive mitochondrial fission induced by Drp1, and reducing mitochondrial dysfunction caused by mitochondrial fragmentation and vacuolation.
Animals ; Electroacupuncture ; Male ; Rats, Sprague-Dawley ; Myocardial Reperfusion Injury/physiopathology* ; Myocytes, Cardiac/cytology* ; Rats ; Acupuncture Points ; Mitochondrial Dynamics ; Humans ; Reactive Oxygen Species/metabolism* ; NF-E2-Related Factor 2/genetics* ; Superoxide Dismutase/metabolism*