Tianxiangdan (TXD), a traditional Chinese herbal remedy, demonstrates efficacy in mitigating myocardial ischemia-reperfusion (I/R)-induced damage. This study employed network pharmacology to evaluate the therapeutic targets and mechanisms of TXD in treating I/R. High-performance liquid chromatography-mass spectrometry (HPLC-MS) identified 86 compounds in TXD. Network pharmacological analysis predicted potential target genes and their modes of action. Cardiac function, ischaemic ST changes, lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD) activity, myocardial fiber, and infarct size were assessed using in vivo and in vitro I/R injury models. Estrogen receptor alpha (ERα) protein expression and estradiol (E2) levels were measured to confirm TXD's impact on estrogen levels and ERα expression. To examine if TXD reduces I/R injury through ERα, an AZD group (300 nmol·L^-1 AZD9496 and 15% TXD serum) was compared to a TXD group (15% TXD serum). The study hypothesized that TXD upregulates the ERα-mediated iron metamorphosis pathway. I/R injury-induced ferroptosis was identified using a Fer-1 group (1.0 μmol·L^-1 Fer-1 and 15% TXD serum) to elucidate the potential association between ferroptosis and ERα proteins. A DCFH-DA probe detected reactive oxygen species (ROS) and Fe²⁺, while Western blotting assessed target protein expression. Both in vitro and in vivo experiments demonstrated that TXD attenuated I/R injury by reducing elevated ST-segment levels, improving cardiac injury biomarkers (LDH, MDA, and SOD), alleviating pathological features, and preventing I/R-induced loss of cell viability in vitro. The effects and mechanisms of TXD on I/R injury-associated ferroptosis were investigated using I/R-induced H9c2 cells. The TXD group showed significantly decreased ROS and Fe²⁺ levels, while the AZ group (treated with AZD9496) exhibited increased levels. The TXD group demonstrated enhanced expression of ERα and glutathione peroxidase 4 (GPX4), with reduced levels of P53 protein and ferritin-heavy polypeptide 1 (FTH1). The AZ group exhibited contrasting effects on these expression levels. The literature indicated a novel connection between ERα and ferroptosis. TXD activates the ERα signaling pathway, promoting protection against I/R-induced myocardial cell ferroptosis. This study provides evidence supporting TXD use for myocardial ischemia treatment, particularly in older female patients who may benefit from its therapeutic outcomes.
Animals ; Ferroptosis/drug effects* ; Estrogen Receptor alpha/genetics* ; Myocardial Reperfusion Injury/genetics* ; Drugs, Chinese Herbal/pharmacology* ; Male ; Mice ; Humans ; Mice, Inbred C57BL ; Estradiol/metabolism*

Ischemic stroke (IS) is a prevalent neurological disorder often resulting in significant disability or mortality. Resveratrol, extracted from Polygonum cuspidatum Sieb. et Zucc. (commonly known as Japanese knotweed), has been recognized for its potent neuroprotective properties. However, the neuroprotective efficacy of its derivative, (E)-4-(3,5-dimethoxystyryl) quinoline (RV02), against ischemic stroke remains inadequately explored. This study aimed to evaluate the protective effects of RV02 on neuronal ischemia-reperfusion injury both in vitro and in vivo. The research utilized an animal model of middle cerebral artery occlusion/reperfusion and SH-SY5Y cells subjected to oxygen-glucose deprivation and reperfusion to simulate ischemic conditions. The findings demonstrate that RV02 attenuates neuronal mitochondrial damage and scavenges reactive oxygen species (ROS) through mitophagy activation. Furthermore, Parkin knockdown was found to abolish RV02's ability to activate mitophagy and neuroprotection in vitro. These results suggest that RV02 shows promise as a neuroprotective agent, with the activation of Parkin-mediated mitophagy potentially serving as the primary mechanism underlying its neuroprotective effects.
Animals ; Ubiquitin-Protein Ligases/genetics* ; Mitophagy/drug effects* ; Resveratrol/analogs & derivatives* ; Neuroprotective Agents/pharmacology* ; Humans ; Neurons/metabolism* ; Reactive Oxygen Species/metabolism* ; Ischemic Stroke/genetics* ; Male ; Quinolines/pharmacology* ; Mice ; Fallopia japonica/chemistry* ; Mitochondria/metabolism* ; Reperfusion Injury/metabolism* ; Rats ; Mice, Inbred C57BL ; Disease Models, Animal

Aralia taibaiensi, widely distributed in western China, particularly in the Qinba Mountains, has been utilized as a folk medicine for treating diabetes, gastropathy, rheumatism, and cardiovascular diseases. Saponins from A. taibaiensis (sAT) have demonstrated protective effects against oxidative stress and mitochondrial dysfunction induced by ischemia/reperfusion (I/R). However, the underlying mechanisms remain unclear. In vivo, middle cerebral artery occlusion/reperfusion (MCAO/R) induced inflammatory infiltration, neuronal injury, cell apoptosis, mitochondrial dysfunction, and oxidative stress in the ischaemic penumbra, which were effectively mitigated by sAT. sAT increased the mRNA and protein expression levels of apelin and its receptor apelin/apelin receptors (ARs) both in vivo and in vitro. (Ala13)-Apelin-13 (F13A) and small interfering RNA (siRNA) abolished the regulatory effects of sAT on neuroprotection mediated by adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)/protein kinase B (Akt). Furthermore, sAT induced apelin/AR expression by simultaneously inhibiting P38 mitogen-activated protein kinase (P38 MAPK)/activating transcription factor 4 (ATF4) and upregulating hypoxia-inducible factor-1α (HIF-1α). Our findings indicate that sAT regulates apelin/AR/AMPK by inhibiting P38 MAPK/ATF4 and upregulating HIF-1a, thereby suppressing oxidative stress and mitochondrial dysfunction.
Animals ; Reperfusion Injury/prevention & control* ; Aralia/chemistry* ; Saponins/administration & dosage* ; AMP-Activated Protein Kinases/genetics* ; Male ; Apelin/genetics* ; Signal Transduction/drug effects* ; Neuroprotective Agents/administration & dosage* ; Brain Ischemia/genetics* ; Rats, Sprague-Dawley ; Rats ; Oxidative Stress/drug effects* ; Apelin Receptors/genetics* ; Humans ; Apoptosis/drug effects* ; Mice

This study investigates the mechanism by which Xintong Granules improve myocardial ischemia-reperfusion injury(MIRI) through the regulation of gut microbiota and their metabolites, specifically short-chain fatty acids(SCFAs). Rats were randomly divided based on body weight into the sham operation group, model group, low-dose Xintong Granules group(1.43 g·kg~(-1)·d~(-1)), medium-dose Xintong Granules group(2.86 g·kg~(-1)·d~(-1)), high-dose Xintong Granules group(5.72 g·kg~(-1)·d~(-1)), and metoprolol group(10 mg·kg~(-1)·d~(-1)). After 14 days of pre-administration, the MIRI rat model was established by ligating the left anterior descending coronary artery. The myocardial infarction area was assessed using the 2,3,5-triphenyltetrazolium chloride(TTC) staining method. Apoptosis in tissue cells was detected by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling(TUNEL) assay. Pathological changes in myocardial cells and colonic tissue were observed using hematoxylin-eosin(HE) staining. The levels of tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), interleukin-6(IL-6), creatine kinase MB isoenzyme(CK-MB), and cardiac troponin T(cTnT) in rat serum were quantitatively measured using enzyme-linked immunosorbent assay(ELISA) kits. The activities of lactate dehydrogenase(LDH), creatine kinase(CK), and superoxide dismutase(SOD) in myocardial tissue, as well as the level of malondialdehyde(MDA), were determined using colorimetric assays. Gut microbiota composition was analyzed by 16S rDNA sequencing, and fecal SCFAs were quantified using gas chromatography-mass spectrometry(GC-MS). The results show that Xintong Granules significantly reduced the myocardial infarction area, suppressed cardiomyocyte apoptosis, and decreased serum levels of pro-inflammatory cytokines(TNF-α, IL-1β, and IL-6), myocardial injury markers(CK-MB, cTnT, LDH, and CK), and oxidative stress marker MDA. Additionally, Xintong Granules significantly improved intestinal inflammation in MIRI rats, regulated gut microbiota composition and diversity, and increased the levels of SCFAs(acetate, propionate, isobutyrate, etc.). In summary, Xintong Granules effectively alleviate MIRI symptoms. This study preliminarily confirms that Xintong Granules exert their inhibitory effects on MIRI by regulating gut microbiota imbalance and increasing SCFA levels.
Animals ; Gastrointestinal Microbiome/drug effects* ; Rats ; Male ; Myocardial Reperfusion Injury/genetics* ; Drugs, Chinese Herbal/administration & dosage* ; Rats, Sprague-Dawley ; Apoptosis/drug effects* ; Humans ; Tumor Necrosis Factor-alpha/metabolism* ; Interleukin-6/genetics* ; Malondialdehyde/metabolism*

OBJECTIVE: To investigate the regulatory effect of electroacupuncture (EA) at "Neiguan" (PC6) on mitochondrial autophagy in rats with myocardial ischemia-reperfusion injury (MIRI) at different phases (ischemia and reperfusion phases), and to explore the bidirectional regulatory effects of EA at "Neiguan" (PC6) and its potential mechanism. METHODS: Forty-five male SD rats were randomly divided into 6 groups according to the random number table method, namely, sham-operation group (n=9), model-A group (n=6), model-B group (n=9), EA-A1 group (n=6), EA-B1 group (n=6), and EA-B2 group (n=9). Except the rats in the sham-operation group, the MIRI model was established in the other groups with the physical ligation and tube pushing method. In the model-A group, the samples were collected directly after ligation, and in the model-B group, the samples were collected after ligation and reperfusion. In the EA-A1 group, EA was delivered while the ligation was performed, and afterwards, the samples were collected. In the EA-B1 group, while the ligation was performed, EA was operated at the same time, and after reperfusion, the samples were collected. In the EA-B2 group, during ligation and the opening of the left anterior descending branch of the coronary artery, EA was delivered, and after reperfusion, the samples were collected. EA was performed at bilateral "Neiguan" (PC6), with a disperse-dense wave, a frequency of 2 Hz/100 Hz, a current of 1 mA, and a duration of 30 min. HE staining was employed to observe the morphology of cardiomyocytes, TUNEL was adopted to detect the apoptosis of cardiomyocytes, transcriptome sequencing was to detect the differentially expressed genes in the left ventricle, JC-1 flow cytometry was to detect the mitochondrial membrane potential (MMP) of cardiomyocytes, Western blot was to detect the protein expression of phosphatase and tensin homolog-induced kinase 1 (Pink1), Parkin and p62 in the left ventricle of rats, and ELISA was to detect the levels of serum creatine kinase isoenzyme (CK-MB) and cardiac troponin I (cTn-I) in the rats. RESULTS: Compared with the sham-operation group, the cardiomyocytes of rats in the model-B group were severely damaged, with disordered arrangement, unclear boundaries, broken muscle fibers, edema and loose distribution; and the cardiomyocytes in the EA-B2 group were slightly damaged, the cell structure was partially unclear, the cells were arranged more regularly, and the intact cardiomyocytes were visible. Compared with the sham-operation group, the apoptosis of cardiomyocytes increased in the model-B group (P<0.001); and when compared with the model-B group, the apoptosis alleviated in the EA-B2 group (P<0.001). The differentially expressed genes among the EA-B2 group, the sham-operation group and the model-B group were closely related to cell autophagy and mitochondrial autophagy. Compared with the sham-operation group, MMP of cardiomyocytes was reduced (P<0.001), the protein expression of Pink1, Parkin, and p62 of the left ventricle and the levels of serum CK-MB and cTn-I were elevated in the model B group (P<0.001). In comparison with model-A group, the MMP of cardiomyocytes and the levels of serum CK-MB and cTn-I were reduced (P<0.001, P<0.05), and the protein expression of Pink1 in the left ventricle rose in the EA-A1 group (P<0.01). Compared with the model-B group, MMP of cardiomyocytes increased (P<0.001), the protein expression of Pink1, Parkin, and p62 of the left ventricle, and the levels of serum CK-MB and cTn-I decreased (P<0.001) in the EA-B1 group and the EA-B2 group. When compared with the EA-A1 group, MMP of cardiomyocytes increased (P<0.001), and the protein expression of Pink1, Parkin, and p62 of the left ventricle, and the levels of serum CK-MB and cTn-I decreased in the EA-B1 group (P<0.01). CONCLUSION EA at "Neiguan" (PC6) can ameliorate MIRI in rats, which may be achieved through the Pink1/Parkin-mediated mitochondrial autophagy pathway. EA can alleviate myocardial injury by enhancing mitochondrial autophagy at the ischemia phase, and it can reduce reperfusion injury by weakening mitochondrial autophagy at the reperfusion phase.
Animals ; Electroacupuncture ; Male ; Myocardial Reperfusion Injury/metabolism* ; Rats, Sprague-Dawley ; Rats ; Acupuncture Points ; Autophagy ; Humans ; Mitochondria/genetics*

OBJECTIVE: To observe the effects of Xingnao Kaiqiao acupuncture technique (for regaining consciousness and opening orifice) on methylation of N6-methyladenosine (m6A), and key methyltransferases and demethylases, so as to clarify the mechanism of acupuncture on cerebral ischemia-reperfusion injury (CIRI). METHODS: Of 68 male Sprague-Dawley rats of SPF grade, 15 rats were randomly selected as a sham-operation group, and the remaining rats were subjected to the model of middle cerebral artery occlusion using the suture ligation. CIRI was induced by ischemia for 2 h followed by reperfusion. Rats that failed to modeling or died were excluded. The rest 45 rats were randomly divided into three groups, i.e. model group, acupuncture group, and non-point acupuncture group, with 15 rats in each group. The rats in the acupuncture group were treated with acupuncture at bilateral "Neiguan" (PC6) and "Shuigou" (GV26). In the non-point acupuncture group, acupuncture was delivered at three non-points, located 3 mm below the bilateral midaxillary line and 3 mm lateral to the tip of the coccyx. One intervention was operated in these two acupuncture groups and the needles were retained for 30 min. Before modeling start and 2 h after ischemia, a laser speckle flowmeter was used to monitor the cerebral blood perfusion. In 2 h of ischemia and 24 h of reperfusion, the neurological behavioral score was evaluated. The volume of rat cerebral infarction was determined by triphenyltetrazolium chloride (TTC) staining, and the level of m6A methylation in ischemic cortical area was detected by Dot blot, and the protein and mRNA expression of the demethylase i.e. fat mass and obesity-associated protein (FTO), AlkB homolog 5 (ALKBH5) and key methyltransferases, i.e. methyltransferase-like 3 (METTL3), methyltransferase-like 14 (METTL14), and Wilms' tumor 1-associated protein (WTAP) in ischemic cortical area were detected by Western blot and real-time PCR. RESULTS: Cerebral blood perfusion decreased by>70% after 2 h ischemia. Compared with the sham-operation group, the neurobehavioral score and the percentage of cerebral infarction volume increased in the model group (P<0.01); the level of m6A methylation in the ischemic cortical area increased (P<0.01), the protein and mRNA expression of FTO decreased (P<0.01), and that of ALKBH5, METTL3, and METTL14 increased (P<0.01, P<0.05) in the model group. When compared with the model group and the non-point acupuncture group, the acupuncture group showed a decrease in the neurobehavioral score and the percentage of cerebral infarction volume (P<0.01), the level of m6A methylation in the ischemic cortical area was reduced (P<0.01, P<0.05), and the protein and mRNA expression of FTO was elevated (P<0.01). CONCLUSION Xingnao Kaiqiao acupuncture technique presents its protective effect on the brain in the rats with CIRI, which is related to up-regulating the expression of FTO and modulating m6A methylation.
Animals ; Rats, Sprague-Dawley ; Male ; Acupuncture Therapy ; Reperfusion Injury/genetics* ; Rats ; Brain Ischemia/genetics* ; Humans ; Adenosine/metabolism* ; Methylation ; Acupuncture Points ; Cerebral Cortex/metabolism*

OBJECTIVE: To explore the neuroprotective effect and underlying mechanism of Xingnao Kaiqiao acupuncture (acupuncture for regaining consciousness and opening orifices) in the rat models of cerebral ischemia-reperfusion injury (CIRI) based on the p53 protein (p53)/solute carrier family 7 member 11 (SLC7A11)/glutathione peroxidase 4 (GPX4) signaling pathway. METHODS: Of 102 male Wistar rats, 20 rats were randomly collected as a sham-operation group. Using a modified external carotid artery filament insertion method, CIRI models were prepared by occluding the middle cerebral artery in the rest rats. After modeling and excluding 1 non-successfully modeled rat and 1 dead one, the other modeled rats were randomized into a model group, an agonist group, an acupuncture group, and an acupuncture + agonist group, 20 rats in each one. Xingnao Kaiqiao acupuncture therapy was delivered in the rats of the acupuncture group and the acupuncture + agonist group. The acupoints included "Shuigou" (GV26), bilateral "Neiguan" (PC6), and "Sanyinjiao" (SP6) on the affected side. Electroacupuncture was attached to "Neiguan" (PC6) and "Sanyinjiao" (SP6) on the affected side, with dense-disperse wave, a frequency of 2 Hz/15 Hz and intensity of 1 mA. The intervention was delivered twice daily, 20 min each time and for 7 consecutive days. In the agonist group and acupuncture+agonist group, p53 agonist, COTI-2 was intraperitoneally injected (15 mg/kg), once daily for 7 consecutive days. Neurological deficit was evaluated using Zausinger's six-point scale. Cerebral infarction volume was quantified by triphenyl tetrazolium chloride (TTC) staining. Histopathological changes were observed using hematoxylin-eosin (HE) staining. Iron deposition was assessed by Prussian blue staining. Mitochondrial ultrastructure in the ischemic cortex was examined under transmission electron microscopy (TEM). Serum iron (Fe²⁺) was measured with chromometry. Malondialdehyde (MDA) and glutathione (GSH) levels in the ischemic hippocampus were determined using thiobarbituric acid and microplate assays, respectively. The mean fluorescence intensity of reactive oxygen species (ROS) in the ischemic cortex was analyzed by flow cytometry. The mRNA and protein expression of GPX4, SLC7A11, and p53 in the ischemic hippocampus were evaluated using quantitative real-time PCR (qRT-PCR) and Western blotting, respectively. RESULTS: Compared with the sham-operated group, the model group exhibited the decrease in neurological deficit score (P<0.01), and the increase in cerebral infarction volume percentage (P<0.01). The changes of brain tissue were presented in extensive cellular necrosis, pyknotic and deeply-stained nuclei, and vacuolar degeneration. The iron deposition was elevated in cortex and hippocampus (P<0.01), mitochondrial membrane density increased, the cristae was broken or reduced, and the outer membrane ruptured. The levels of Fe²⁺ and MDA, as well as the mean flourscence intensity of ROS were elevated (P<0.01) and the level of GSH was reduced (P<0.01). The mRNA and protein expression of GPX4 and SLC7A11 was reduced (P<0.01), while that of p53 rose (P<0.01). When compared with the model group, in the agonist group, the neurological deficit score was reduced (P<0.05), the percentage of infarction volume was higher (P<0.01), the histopathological damage was further exacerbated, and the percentage of iron deposition increased in the cortex and hippocampus (P<0.01). The mitochondrial quantity decreased, the membrane density increased, the mitochondrial cristae were broken or reduced, and the outer membrane was ruptured. The levels of Fe²⁺ and MDA, as well as the mean flourscence intensity of ROS were higher (P<0.01, P<0.05) and the level of GSH was reduced (P<0.05). The mRNA and protein expression of GPX4 and SLC7A11 decreased (P<0.01, P<0.05), while that of p53 was elevated (P<0.01). Besides, in comparison with the model group, the neurological deficit score was higher in the acupuncture group and the acupuncture + agonist group (P<0.01, P<0.05), the percentage of cerebral infarction volume was lower in the acupuncture group (P<0.01), the pathological damage of brain tissue was alleviated in the acupuncture group and the acupuncture + agonist group, and the percentage of iron depositiondecreased in the cortex and hippocampus (P<0.01). The mitochondrial structure was relatively clear, the mitochondrial cristae were fractured or reduced mildly in the acupuncture group and the acupuncture + agonist group. The levels of Fe²⁺ and MDA, as well as the mean flourscence intensity of ROS were lower (P<0.01) and the level of GSH was higher (P<0.01) in the acupuncture group. The mean fluorescence intensity of ROS were dropped (P<0.01) in the acupuncture + agonist group. The mRNA expression of GPX4 and SLC7A11 was elevated (P<0.01) and that of p53 was reduced (P<0.01, P<0.05) in either the acupuncture group or the acupuncture + agonist group; the protein expression of GPX4 and SLC7A11 rose (P<0.05, P<0.01) and that of p53 was dropped (P<0.01) in the acupuncture group; and the protein expression of p53 was also lower in the acupuncture + agonist group (P<0.05). When compared with the agonist group, in the acupuncture + agonist group, neurological deficit score increased (P<0.01), the percentage of cerebral infarction volume decreased (P<0.01), the pathological brain tissue damage was reduced, the percentage of iron deposition in cortex and hippocampus decreased (P<0.01), the mitochondrial structure was relatively clear and the cristae broken or reduced slightly; the levels of Fe²⁺ and MDA, as well as the mean fluorescence intensity of ROS were dropped (P<0.01), while the level of GSH increased (P<0.05); the mRNA and protein expression of GPX4 and SLC7411 was elevated (P<0.01, P<0.05), and that of p53 reduced (P<0.01). In comparison with the acupuncture + agonist group, in the acupuncture group, the neurological deficit score increased (P<0.05), the percentage of cerebral infarction volume decreased (P<0.05), the pathological brain tissue damage was alleviated, the percentage of iron deposition in cortex and hippocampus decreased (P<0.01), the mitochondrial structure was normal in tendency; the levels of Fe²⁺ and MDA, as well as the mean fluorescence intensity of ROS were reduced (P<0.05), while the level of GSH rose (P<0.01); the mRNA and protein expression of GPX4 and SLC7411 was elevated (P<0.01, P<0.05), and that of p53 reduced (P<0.01, P<0.05). CONCLUSION Xingnao Kaiqiao acupuncture can alleviate neurological damage in CIRI rats, which is obtained probably by inhibiting ferroptosis through p53/SLC7A11/GPX4 pathway.
Animals ; Reperfusion Injury/metabolism* ; Male ; Acupuncture Therapy ; Rats ; Tumor Suppressor Protein p53/genetics* ; Brain Ischemia/metabolism* ; Rats, Wistar ; Signal Transduction ; Humans ; Phospholipid Hydroperoxide Glutathione Peroxidase/genetics* ; Disease Models, Animal ; Acupuncture Points ; Amino Acid Transport System y+/genetics*

BACKGROUND: The protective effect of mesenchymal stem cells (MSCs) on cardiac ischemia-reperfusion (I/R) injury has been widely reported. Dental pulp-derived mesenchymal stem cells (DP-MSCs) have therapeutic effects on various diseases, including diabetes and cirrhosis. This study aimed to determine the therapeutic effects of DP-MSCs on I/R injury and elucidate the underlying mechanism. METHODS: Myocardial I/R injury model mice were treated with DP-MSCs or a miR-19a-3p mimic. The infarct volume, fibrotic area, pyroptosis, inflammation level, and cardiac function were measured. Cardiomyocytes exposed to hypoxia-reoxygenation were transfected with the miR-19a-3p mimic, miR-19a-3p inhibitor, or negative control. Pyroptosis and protein expression in the interferon regulatory factor 8/mitogen-activated protein kinase (IRF-8/MAPK) pathway were measured. RESULTS: DP-MSCs protected cardiac function in cardiac I/R-injured mice and inhibited cardiomyocyte pyroptosis. The upregulation of miR-19a-3p protected cardiac function, inhibited cardiomyocyte pyroptosis, and inhibited IRF-8/MAPK signaling in cardiac I/R-injured mice. DP-MSCs inhibited cardiomyocyte pyroptosis and the IRF-8/MAPK signaling by upregulating the miR-19a-3p levels in cardiomyocytes injured by I/R. CONCLUSION DP-MSCs protected cardiac function by inhibiting cardiomyocyte pyroptosis through miR-19a-3p under I/R conditions.
Animals ; MicroRNAs/metabolism* ; Pyroptosis/genetics* ; Mesenchymal Stem Cells/metabolism* ; Myocytes, Cardiac/cytology* ; Mice ; Male ; Mice, Inbred C57BL ; Dental Pulp/cytology* ; Myocardial Reperfusion Injury/therapy* ; MAP Kinase Signaling System/physiology*

This study aims to investigate the protective effects and mechanisms of polysaccharide extract PCP1 from Polygonatum cyrtonema in ameliorating cerebral ischemia-reperfusion(I/R) injury in rats through modulation of the Toll-like receptor 4(TLR4)/NOD-like receptor protein 3(NLRP3) signaling pathway. In vivo, SD rats were randomly divided into the sham group, model group, PCP1 group, nimodipine(NMDP) group, and TLR4 signaling inhibitor(TAK-242) group. A middle cerebral artery occlusion/reperfusion(MCAO/R) model was established, and neurological deficit scores and infarct size were evaluated 24 hours after reperfusion. Hematoxylin-eosin(HE) and Nissl staining were used to observe pathological changes in ischemic brain tissue. Transmission electron microscopy(TEM) assessed ultrastructural damage in cortical neurons. Enzyme-linked immunosorbent assay(ELISA) was used to measure the levels of interleukin-1β(IL-1β), interleukin-6(IL-6), interleukin-18(IL-18), tumor necrosis factor-α(TNF-α), interleukin-10(IL-10), and nitric oxide(NO) in serum. Immunofluorescence was used to analyze the expression of TLR4 and NLRP3 proteins. In vitro, a BV2 microglial cell oxygen-glucose deprivation/reperfusion(OGD/R) model was established, and cells were divided into the control, OGD/R, PCP1, TAK-242, and PCP1 + TLR4 activator lipopolysaccharide(LPS) groups. The CCK-8 assay evaluated BV2 cell viability, and ELISA determined NO release. Western blot was used to analyze the expression of TLR4, NLRP3, and downstream pathway-related proteins. The results indicated that, compared with the model group, PCP1 significantly reduced neurological deficit scores, infarct size, ischemic tissue pathology, cortical cell damage, and the levels of inflammatory factors IL-1β, IL-6, IL-18, TNF-α, and NO(P<0.01). It also elevated IL-10 levels(P<0.01) and decreased the expression of TLR4 and NLRP3 proteins(P<0.05, P<0.01). Moreover, in vitro results showed that, compared with the OGD/R group, PCP1 significantly improved BV2 cell viability(P<0.05, P<0.01), reduced cell NO levels induced by OGD/R(P<0.01), and inhibited the expression of TLR4-related inflammatory pathway proteins, including TLR4, myeloid differentiation factor 88(MyD88), tumor necrosis factor receptor-associated factor 6(TRAF6), phosphorylated nuclear factor-kappaB dimer RelA(p-p65)/nuclear factor-kappaB dimer RelA(p65), NLRP3, cleaved-caspase-1, apoptosis-associated speck-like protein(ASC), GSDMD-N, IL-1β, and IL-18(P<0.05, P<0.01). The protective effects of PCP1 were reversed by LPS stimulation. In conclusion, PCP1 ameliorates cerebral I/R injury by modulating the TLR4/NLRP3 signaling pathway, exerting anti-inflammatory and anti-pyroptotic effects.
Animals ; Toll-Like Receptor 4/genetics* ; NLR Family, Pyrin Domain-Containing 3 Protein/genetics* ; Rats, Sprague-Dawley ; Rats ; Reperfusion Injury/genetics* ; Male ; Signal Transduction/drug effects* ; Polysaccharides/isolation & purification* ; Polygonatum/chemistry* ; Brain Ischemia/genetics* ; Drugs, Chinese Herbal/administration & dosage* ; Mice ; Humans

This study aims to investigate the molecular mechanism by which naringin alleviates cerebral ischemia/reperfusion(CI/R) injury through DRP1/LRRK2/MCU signaling axis. A total of 60 SD rats were randomly divided into the sham group, the model group, the sodium Danshensu group, and low-, medium-, and high-dose(50, 100, and 200 mg·kg~(-1)) naringin groups, with 10 rats in each group. Except for the sham group, a transient middle cerebral artery occlusion/reperfusion(tMCAO/R) model was established in SD rats using the suture method. Longa 5-point scale was used to assess neurological deficits. 2,3,5-Triphenyl tetrazolium chloride(TTC) staining was used to detect the volume percentage of cerebral infarction in rats. Hematoxylin-eosin(HE) staining and Nissl staining were employed to assess neuronal structural alterations and the number of Nissl bodies in cortex, respectively. Western blot was used to determine the protein expression levels of B-cell lymphoma-2 gene(Bcl-2), Bcl-2-associated X protein(Bax), cleaved cysteine-aspartate protease-3(cleaved caspase-3), mitochondrial calcium uniporter(MCU), microtubule-associated protein 1 light chain 3(LC3), and P62. Mitochondrial structure and autophagy in cortical neurons were observed by transmission electron microscopy. Immunofluorescence assay was used to quantify the fluorescence intensities of MCU and mitochondrial calcium ion, as well as the co-localization of dynamin-related protein 1(DRP1) with leucine-rich repeat kinase 2(LRRK2) and translocase of outer mitochondrial membrane 20(TOMM20) with LC3 in cortical mitochondria. The results showed that compared with the model group, naringin significantly decreased the volume percentage of cerebral infarction and neurological deficit score in tMCAO/R rats, alleviated the structural damage and Nissl body loss of cortical neurons in tMCAO/R rats, inhibited autophagosomes in cortical neurons, and increased the average diameter of cortical mitochondria. The Western blot results showed that compared to the sham group, the model group exhibited increased levels of cleaved caspase-3, Bax, MCU, and the LC3Ⅱ/LC3Ⅰ ratio in the cortex and reduced protein levels of Bcl-2 and P62. However, naringin down-regulated the protein expression of cleaved caspase-3, Bax, MCU and the ratio of LC3Ⅱ/LC3Ⅰ ratio and up-regulated the expression of Bcl-2 and P62 proteins in cortical area. In addition, immunofluorescence analysis showed that compared with the model group, naringin and positive drug treatments significantly decreased the fluorescence intensities of MCU and mitochondrial calcium ion. Meanwhile, the co-localization of DRP1 with LRRK2 and TOMM20 with LC3 in cortical mitochondria was also decreased significantly after the intervention. These findings suggest that naringin can alleviate cortical neuronal damage in tMCAO/R rats by inhibiting DRP1/LRRK2/MCU-mediated mitochondrial fragmentation and the resultant excessive mitophagy.
Animals ; Rats, Sprague-Dawley ; Reperfusion Injury/genetics* ; Flavanones/administration & dosage* ; Rats ; Dynamins/genetics* ; Male ; Brain Ischemia/genetics* ; Protein Serine-Threonine Kinases/genetics* ; Signal Transduction/drug effects* ; Humans ; Drugs, Chinese Herbal/administration & dosage*