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OBJECTIVE@#To explore the protective effect of bloodletting acupuncture at twelve Jing-well points on hand (BAJP) on acute hypobaric hypoxia (AHH)-induced brain injury in rats and its possible mechanisms.@*METHODS@#Seventy-five Sprague Dawley rats were divided into 5 groups by a random number table (n=15), including control, model, BAJP, BAJP+3-methyladenine (3-MA), and bloodletting acupuncture at non-acupoint (BANA, tail tip blooding) groups. After 7-day pre-treatment, AHH models were established using hypobaric oxygen chambers. The levels of S100B, glial fibrillary acidic protein (GFAP), superoxide dismutase (SOD), and malondialdehyde (MDA) in serum were measured by enzyme-linked immunosorbent assay. Hematoxylin-eosin staining and the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling method were used to assess hippocampal histopathology and apoptosis. Transmission electron microscopy assay was used to observe mitochondrial damage and autophagosomes in hippocampal tissues. Flow cytometry was used to detect mitochondrial membrane potential (MMP). The mitochondrial respiratory chain complexes I, III and IV activities and ATPase in hippocampal tissue were evaluated, respectively. Western blot analysis was used to detect the protein expressions of Beclin1, autophagy protein 5 (ATG5), microtubule-associated protein 1 light chain 3 beta (LC3B), phosphatase and tensin homolog induced kinase 1 (PINK1), and Parkin in hippocampal tissues. The mRNA expressions of Beclin1, ATG5 and LC3-II were analyzed by quantitative real-time polymerase chain reaction.@*RESULTS@#BAJP treatment reduced hippocampal tissue injury and inhibited hippocampal cell apoptosis in AHH rats. BAJP reduced oxidative stress by decreasing S100B, GFAP and MDA levels and increasing SOD level in the serum of AHH rats (P<0.05 or P<0.01). Then, BAJP increased MMP, the mitochondrial respiratory chain complexes I, III and IV activities, and the mitochondrial ATPase activity in AHH rats (all P<0.01). BAJP improved mitochondrial swelling and increased the autophagosome number in hippocampal tissue of AHH rats. Moreover, BAJP treatment increased the protein and mRNA expressions of Beclin1 and ATG5 and LC3-II/LC3-I ratio in AHH rats (all P<0.01) and activated the PINK1/Parkin pathway (P<0.01). Finally, 3-MA attenuated the therapeutic effect of BAJP on AHH rats (P<0.05 or P<0.01).@*CONCLUSION@#BAJP was an effective treatment for AHH-induced brain injury, and the mechanism might be through reducing hippocampal tissue injury via increasing the PINK1/Parkin pathway and enhancement of mitochondrial autophagy.
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ObjectiveTo establish a rat model of diabetic wound by feeding on a high-fat and high-sugar diet combined with intraperitoneal injection of streptozotocin （STZ） and surgical preparation of full-thickness skin defects， observe the effect of cinnamaldehyde on the wound healing of diabetes rats， and explore the therapeutic mechanism of cinnamaldehyde in improving wound healing of diabetes rats based on the PTEN-induced putative kinase （PINK1）/Parkin pathway-mediated mitochondrial autophagy. MethodForty-eight male SD rats were randomly divided into blank group （n=12） and diabetes group （n=36）. The diabetes group was further randomly divided into model group， cinnamaldehyde group， and Beifuxin group， with 12 rats in each group. The blank group and the model group received routine disinfection with physiological saline after creating the wounds， while the cinnamaldehyde group received topical application of polyethylene glycol 400 （PEG 400） gel containing 4 μmol·L-1 cinnamaldehyde， and the Beifuxin group received topical application of Beifuxin gel. Dressings were changed once daily. The wound healing rate of each group was observed. On the 7th and 14th days after intervention， the wound tissues of the rats were collected. Hematoxylin and eosin （HE） staining was performed to observe the pathological changes in the local tissues. Immunohistochemistry （IHC） was used to detect the expression of interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， vascular endothelial growth factor （VEGF）， and collagen fibers. Immunofluorescence （IF） and Real-time polymerase chain reaction （Real-time PCR） were used to detect the protein， and mRNA expression of PINK1， Parkin， microtubule-associated protein 1 light chain 3 Ⅱ （LC3 Ⅱ）. ResultAfter intraperitoneal injection of STZ， compared with the blank group， the random blood glucose values of rats in the diabetic group increased significantly （P<0.01）， all higher than 16.7 mmol·L-1， and persistently hyperglycemic for some time after modeling. Compared with the blank group， the model group showed poor growth and healing of granulation tissue in the wounds， and the wound healing rate decreased （P<0.01）. On the 7th day after intervention， the blank group had squamous epithelial coverage on the wounds. Compared with the blank group， the model group only had a small amount of scab at the wound edges， with a large number of infiltrating inflammatory cells in the wounds. The protein expression levels of IL-6 and TNF-α in the tissues increased （P<0.01）， and the protein and mRNA levels of PINK1， Parkin， and LC3Ⅱ decreased （P<0.01）. On the 14th day after the intervention， the granulation tissue in the wounds of the blank group was mature and well-healed. Compared with the blank group， the model group still had infiltrating inflammatory cells and red blood cell exudation. The protein expression levels of VEGF and collagen fibers in the tissues decreased （P<0.01）， and the protein and mRNA expression levels of PINK1， Parkin， and LC3Ⅱ increased （P<0.01）. Compared with the model group， the cinnamaldehyde group and the Beifuxin group showed better wound healing， with increased wound healing rates （P<0.01）. On the 7th day after intervention， the protein expression levels of IL-6 and TNF-α in the tissues decreased （P<0.01）， and the protein and mRNA expression levels of PINK1， Parkin， and LC3Ⅱ increased （P<0.01）. On the 14th day after intervention， the protein expression levels of VEGF and collagen fibers in the tissues increased （P<0.01）， and the protein and mRNA expression levels of PINK1， Parkin， and LC3Ⅱ decreased （P<0.01）. ConclusionCinnamaldehyde can promote the wound healing of diabetes rats by increasing the wound healing rate， reducing the levels of inflammatory factors IL-6 and TNF-α， and increasing the levels of VEGF and collagen fibers. Its mechanism may be related to the regulation of the PINK1/Parkin signaling pathway， activation of mitochondrial autophagy， inhibition of inflammatory responses， and promotion of angiogenesis and collagen synthesis， thereby promoting the wound healing of diabetes rats.
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Objective To investigate the protective effect and mechanism of polydatin ( PD) on allergic rhinitis (AH) by regulating mitophagy through PINK1- Parkin signaling pathway, and to provide a new target for clinical treatment of AH.Methods Thirty-two BALB/c murine were randomly divided into 4 groups: control group, OVA group, PD low-dose (30 mg • kg 1 ) and high-dose ( 45 mg • kg 1 ) treatment groups.At the end of modeling, the total number of sneezing and nasal nibbing of murine was recorded.HE staining was used to observe the morphology of na- sal mucosal epithelium and eosinophil infiltration.Western blot was used to detect the expression of P1NK1 , Parkin, TOM20 and mitochondrial apoptosis- related proteins Bax, Bcl-2, caspase-3, cleaved- caspase-3 and Cytochrome C.Hie expression of P1NK1 and cleaved-caspase-3 in nasal epithelial cells (HNEpC) was observed by immunofluorescence.Re¬sults The frequency of sneezing and nasal rubbing movements was significantly increased, the nasal mu¬cosa epithelium was thickened, and eosinophils were accumulated in AH murine , these results were reversed after PD treatment.Western blot results shower] that signaling proteins PINK1/Parkin anrl pro-apoptotie pro¬teins, including Bax, caspase-3, cleaved-caspase-3 and Cytochrome C were significantly overexpressed, the expression of TOM20 and Bcl-2 was decreased in OVA group, and PD up-regulated the levels of P1NK1 , Parkin, as well as Bcl-2 and inhibited the expression of TDM20 and pro-apoptotic proteins, while after pre- treatment with mitochondrial division inhibitor 1 ( Mdi- vi-1 ) , the expression of P1NK1 and Parkin was re¬duced , the expression of TOM20 was increased, while PD treatment did not significantly affect this effect.From the immunofluorescence results, it can be seen that the level of P1NK1 was increased after IL-13 stim¬ulation of HNEpCs compared with the control group, and PD further up-regulated the expression of P1NK1 , which was suppressed after pretreatment with Mdivi-1 , while PD did not change this phenomenon.Western blot results for P1NK1 and cleaved-caspase-3 were con¬firmed by immunofluorescence.Conclusion PD may activate mitophagy through the P1NK1 -Parkin signaling pathway, thereby protecting against AR.
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OBJECTIVE：To investig ate the effects of tenuifolin （TEN）on brain mitochondrial autophagy in Aizheimer ’s disease（AD）model mice. METHODS ：Totally 50 male APP/PS1 double transgenic mice were randomly divided into model group，TEN medium-dose+ 3-MA group [TEN 40 mg/（kg·d）+autophagy inhibitor 3-MA 30 mg/（kg·d）] and TEN low-dose ， medium-dose and high-dose groups [ 20，40，80 mg/（kg·d）]，with 10 mice in each group. In addition ，10 wild-type homologous mice were included in normal control group. Administration groups were intragastrically given corresponding drug solution ；normal control group and model group were intragastrically given 0.3％ sodium carboxymethyl cellulose solution ，once a day ，0.01 mL/g， for consecutive 3 months. After last administration ，positive expression [measured by integrated optical density （IOD）] of microtubule associated protein 1 light chain 3（LC3）in neuron was detected ；mRNA expressions of LC3，ubiquitin-binding protein p62，Cathepsin D ，Rab7，phosphatase and tensin homolog deleted on chromosome ten gene-induced putative kinase 1（PINK1） and E 3 ligase（Parkin）as well as protein expressions of LC 3，p62，PINK1 and Parkin were detected in brain mitochondria. RESULTS：Compared with normal control group ，IOD value of LC 3 in neuron as well as mRNA and protein expressions of LC 3， p62，PINK1 and Parkin in brain mitochondria were all increased significantly in model group （P＜0.05 or P＜0.01），while mRNA expressions of Cathepsin D and Rab 7 were decreased significantly （P＜0.05 or P＜0.01）. Compared wit h model group ，IOD values of LC 3（except for TEN low-dose and medium-dose groups ） in neuron ，mRNA expressions of LC 3，Cathepsin D ，Rab7， PINK1（except for TEN low-dose group ）and Parkin （except for TEN low-dose group ） in brain mitochondria as well as protein expressions of LC 3 （except for TEN medium-dose group），PINK1（except fo r TEN high-dose group decreased significantly）and Parkin （except for TEN low-dose group decreased significantly ）were increased significantly in TEN low-dose ， medium-dose and high-dose groups （P＜0.05 or P＜0.01）；mRNA（except for TEN low-dose group ）and protein expressions of p62 were decreased significantly （P＜0.05 or P＜0.01）. Compared with TEN medium-dose group ，the changes of above indexes were inhibited significantly in TEN medium-dose + 3-MA group （P＜0.05 or P＜0.01）. CONCLUSIONS ：TEN can induce mitophagy in brain tissue of AD model mice by activating PINK 1/Parkin signaling pathway and improve lysosome function.