ABSTRACT
Aim To research the neuroprotective effect of Haikun Shenxi (HKSX) medicated serum on N2a/ App695 cells and the underlying mechanism. Methods HKSX medicated serum was prepared and carbohydrate components in it was analyzed using high performance thin layer chromatography (HPTLC) . N2a/ App695 cells were intervened with HKSX medicated serum, the cytotoxicity of HKSX medicated serum was measured by MTT; AP[_
ABSTRACT
In addition to providing energy for cells, mitochondria also participate in calcium homeostasis, cell information transfer, cell apoptosis, cell growth and differentiation. Therefore, maintaining mitochondrial homeostasis is very crucial for the body to carry out normal life activities. Ubiquitination, a post-translational modification of proteins, is involved in various physiological and pathological processes of cells by regulating mitochondrial homeostasis. However, the mechanism by which ubiquitination regulates mitochondrial homeostasis has not been summarized, especially the effect of Parkin protein on cardiovascular diseases. In this paper, the specific mechanism of mitochondrial homeostasis regulated by ubiquitination of Parkin protein is discussed, and the influence of mitochondrial homeostasis imbalance on cardiovascular diseases is reviewed, with a view to providing potential therapeutic strategies for the clinical treatment of cardiovascular diseases.
ABSTRACT
Aim To investigate the targeting mechanism of miR-23b on PINKl/Parkin pathway in transdifferentiation of NRK-52E cellsinduced by TGF-β1, and to elucidate the intervention mechanism of Qingshen granules drug-containing serum on NRK-52E cell transdifferentiation. Methods Ultra-high performance liquid chromatography ( UPLC ) fingerprinting method was used to analyze Qingshen granules. The NRK-52E transdifferentiation model induced by TGF-β1 was constructed. The NRK-52E cells were divided into simulated no-load control group, miR-23b-5p simulated group, inhibitor no-load control group, and miR-23b-5p inhibitor group, after transfection with siRNA, and the effect of miR-23b-5p on PINK1 expression was ob-served. The NRK-52E cells were then divided into normal group, TGF-(31 group, Qingshen granule group, miR-23 b-mimic group, miR-23 b-mimic group, and miR-23b-mimic + Qingshen granule group. Western blot was used to detect the expression of Pinkl, Parkin, LC3 n, Beclin-1, P62 and a-SMA proteins, and RT- PCR was used to detect the expression of miR-23 b-5p, Pinkl, Parkin, Beclin-1 and a-SMA mRNA in NRK- 52E cells. Dual-Luciferase Reporter gene experiment was used to detect the targeting relationship between miR-23b-5p and PINKL Results UPLC fingerprinting method found 11 active components in Qingshen granules. After overexpression of miR-23b-5p, the expression of PINkl mRNA significantly increased (P 0. 05 ). The experimental results showed that the expressions of miR- 23b-5p, Pinkl, Parkin, Beclin-1, LC3 II and LC3 II/ I ratio in TGF-β1 group were significantly lower than those in normal group, but the expressions of P62 and a-SMA were significantly higher than those in normal group ( P <0.05). The expressions of miR-23 b-5 p, Pinkl, Parkin, Beclin-1, LC3 II and LC3 11/ I ratio in Qingshen granule group and miR-23 b-mimic group were significantly higher than those in TGF-β1 group, and the expressions of P62 and a-SMA were significantly lower than those in TGF-β1 group (P < 0. 05 ). The performance of miR-23 b-mimic + Qingshen granule group was better than that of miR-23 b-mimic group (P < 0. 05 ). Conclusions Qingshen granules can up- regulate the expression of miR-23b-5p in NRK-52E cellsand inhibit the transdifferentiation process of NRK- 52E cells by enhancing the mitochondrial autophagy activity mediated by PINKl/Parkin pathway.
ABSTRACT
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.
ABSTRACT
Aim To investigate the effects of total saponins from Trillium tschonoskii maxim(TST)on cognitive impairment and mitochondrial autophagy in aging rats induced by D-galactose(D-gal). Methods Male SD rats were randomly divided into normal control group,model group(D-gal,subcutaneous injection),intervention group(TST,low,medium and high dose groups by intragastric administration),with 10 rats in each group,and administered for 6 weeks. Morris water maze was used to evaluate the cognitive function. HE and Nissl staining were used to test the hippocampal and brain cortex morphology. Immunohistochemistry staining was applied to detect the localization expression of Pink1 and Parkin. Western blot was employed to detect the expressions of Pink1,Parkin,LC3-Ⅱ,p62 and Beclin1. Results Compared with the normal control group,the escape latency time was prolonged and the number of crossing platform decreased in D-gal model group(P<0.05). The number of neurons in hippocampus significantly decreased. The positive cells labeled by Pink1 and Parkin staining in hippocampus significantly decreased. The expressions of Pink1,Parkin,LC3-Ⅱ and Beclin1 were markedly reduced,while the expression of p62 was significantly raised(P<0.05). Compared with D-gal model group,the escape latency time of TST dose groups was shortened,the Times of crossing the platform was more,and the time of staying in the platform quadrant increased(P<0.05). The number of neurons in hippocampus significantly increased. The positive cells labeled by Pink1 and Parkin staining in hippocampus significantly increased. The expressions of Pink1,Parkin,LC3-Ⅱ and Beclin1 in hippocampus were apparently up-regulated,while the protein expression of p62 was evidently down-regulated(P<0.05). Conclusions TST has neuroprotective effects on the learning and memory capacities in aging rats induced by D-gal,which may be related to the increasing levels of Pink1,Parkin,LC3-Ⅱ and Beclin1 proteins and the activation of mitochondrial autophagy.
ABSTRACT
Aim To investigate the potential mechanism of osthole promoting autophagy in cervical cancer HeLa cells. Methods HeLa cells were treated with various concentrations of Osthole(0,10,20,40,80,160,240,320 mg·L-1). MTT was used to detect cell vitality. Transmission electron microscopy(TEM)was used to observe the morphology of HeLa cells after osthole intervention. Mondane sulfonyl cadaverine(MDC)staining was used to dectect the level of autophagy. Western blot was employed to analyze the expression levels of mitochondrial protein MFN1 and DPR1. JC-1 flourescence probe was applied to detect mitochondrial membrane potential. Flow cytometry was used to deteminet the release of reactive oxygen species(ROS). A transplanted tumor model of cervical cancer was established in vivo in nude mice. Western blot was used to detect the protein expression levels of PINK1,Parkin and LC3Ⅱ/. Results Osthole could inhibit the proliferation of HeLa cells significantly. Transmission electron microscopy showed that typical autophagosomes were formed in HeLa cells after osthole intervention. The fluorescence intensity of MDC was enhanced. The expression of mitochondrial fusion protein MFN1 was down-regulated after HeLa cells pretreated with osthole,and mitochondrial fission protein DRP1 was up-regulated. Mitochondrial membrane potential decreased. ROS production of HeLa cells was increased by flow cytometry,which could be reversed by autophagy inhibitor 3-MA. Tumor weight in nude mice was inhibited by osthole obviously,which might restrain cervical cancer. Western blot result indicated that the key factors of mitochondrial autophagy PINK1,Parkin and LC3Ⅱ/ratio were up-regulated in HeLa cells. Conclusions Osthole could induce autophagy in HeLa cells and its mechanism may be related to ROS production and PINK1/Parkin pathway.
ABSTRACT
Aim To predict the potential mechanism of ophiopogonin D (OPD) against pulmonary fibrosis by network pharmacology, and further verify it by experiment in vivo. Methods This study found that ophiopogon was the most frequently used drug in the treatment of pulmonary fibrosis with deficiency of Qi and Yin through data mining. In order to explore its material basis, network pharmacology analysis was carried out. A model of pulmonary fibrosis was established by bleomycin, and different concentrations of ophiopogonin D were administered to verify the results of the pharmacological network. Results Firstly, through network pharmacology analysis, it was found that mitophagy might be the potential target for ophiopogon to exert anti-pulmonary fibrosis effect. Meanwhile, network topology analysis showed that OPD had the greatest relationship with mitophagy. Animal experiments showed that OPD could relieve pulmonary fibrosis and reduce collagen deposition in mice. At the same time, the detection of mitophagy related proteins showed that the compound could increase the expression of PINK1 and Parkin proteins, reduce the content of P62 protein in lung tissue, and reduce the intracellular ROS level. Conclusions OPD can improve mitochondrial function and play an anti-pulmonary fibrosis role by promoting PINKl/Parkin dependent mitophagy in lung tissue.
ABSTRACT
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.
ABSTRACT
Mitophagy is one of the important targets for the prevention and treatment of myocardial ischemia/reperfusion injury (MIRI). Moderate mitophagy can remove damaged mitochondria, inhibit excessive reactive oxygen species accumulation, and protect mitochondria from damage. However, excessive enhancement of mitophagy greatly reduces adenosine triphosphate production and energy supply for cell survival, and aggravates cell death. How dysfunctional mitochondria are selectively recognized and engulfed is related to the interaction of adaptors on the mitochondrial membrane, which mainly include phosphatase and tensin homolog deleted on chromosome ten (PTEN)-induced kinase 1/Parkin, hypoxia-inducible factor-1 α/Bcl-2 and adenovirus e1b19k Da interacting protein 3, FUN-14 domain containing protein 1 receptor-mediated mitophagy pathway and so on. In this review, the authors briefly summarize the main pathways currently studied on mitophagy and the relationship between mitophagy and MIRI, and incorporate and analyze research data on prevention and treatment of MIRI with Chinese medicine, thereby provide relevant theoretical basis and treatment ideas for clinical prevention of MIRI.
Subject(s)
Humans , Mitochondria/metabolism , Mitophagy/genetics , Myocardial Reperfusion Injury , Protein Kinases/metabolismABSTRACT
This study investigated the mechanism of Danggui Shaoyao Powder(DSP) against mitophagy in rat model of Alzheimer's disease(AD) induced by streptozotocin(STZ) based on PTEN induced putative kinase 1(PINK1)-Parkin signaling pathway. The AD rat model was established by injecting STZ into the lateral ventricle, and the rats were divided into normal group, model group, DSP low-dose group(12 g·kg~(-1)·d~(-1)), DSP medium-dose group(24 g·kg~(-1)·d~(-1)), and DSP high-dose group(36 g·kg~(-1)·d~(-1)). Morris water maze test was used to detect the learning and memory function of the rats, and transmission electron microscopy and immunofluorescence were employed to detect mitophagy. The protein expression levels of PINK1, Parkin, LC3BⅠ/LC3BⅡ, and p62 were assayed by Western blot. Compared with the normal group, the model group showed a significant decrease in the learning and memory function(P<0.01), reduced protein expression of PINK1 and Parkin(P<0.05), increased protein expression of LC3BⅠ/LC3BⅡ and p62(P<0.05), and decreased occurrence of mitophagy(P<0.01). Compared with the model group, the DSP medium-and high-dose groups notably improved the learning and memory ability of AD rats, which mainly manifested as shortened escape latency, leng-thened time in target quadrants and elevated number of crossing the platform(P<0.05 or P<0.01), remarkably activated mitophagy(P<0.05), up-regulated the protein expression of PINK1 and Parkin, and down-regulated the protein expression of LC3BⅠ/LC3BⅡ and p62(P<0.05 or P<0.01). These results demonstrated that DSP might promote mitophagy mediated by PINK1-Parkin pathway to remove damaged mitochondria and improve mitochondrial function, thereby exerting a neuroprotective effect.
Subject(s)
Rats , Animals , Mitophagy , Alzheimer Disease/genetics , Powders , Protein Kinases/metabolism , Ubiquitin-Protein Ligases/metabolismABSTRACT
OBJECTIVES@#To study the effect of ligustrazine injection on mitophagy in neonatal rats with hypoxic-ischemic encephalopathy (HIE) and its molecular mechanism.@*METHODS@#Neonatal Sprague-Dawley rats, aged 7 days, were randomly divided into a sham-operation group with 8 rats, a model group with 12 rats, and a ligustrazine group with 12 rats. The rats in the model group and the ligustrazine group were used to establish a neonatal rat model of HIE by ligation of the left common carotid artery followed by hypoxia treatment, and blood vessels were exposed without any other treatment for the rats in the sham-operation group. The rats in the ligustrazine group were intraperitoneally injected with ligustrazine (20 mg/kg) daily after hypoxia-ischemia, and those in the sham-operation group and the model group were intraperitoneally injected with an equal volume of normal saline daily. Samples were collected after 7 days of treatment. Hematoxylin and eosin staining and Nissl staining were used to observe the pathological changes of neurons in brain tissue; immunohistochemical staining was used to observe the positive expression of PINK1 and Parkin in the hippocampus and cortex; TUNEL staining was used to measure neuronal apoptosis; Western blotting was used to measure the expression levels of the mitophagy pathway proteins PINK1 and Parkin and the autophagy-related proteins Beclin-1, microtubule-associated protein 1 light chain 3 (LC3), and ubiquitin-binding protein (P62).@*RESULTS@#Compared with the sham-operation group, the model group had a significant reduction in the number of neurons, an increase in intercellular space, loose arrangement, lipid vacuolization, and a reduction in Nissl bodies. The increased positive expression of PINK1 and Parkin, apoptosis rate of neurons, and protein expression levels of PINK1, Parkin, Beclin1 and LC3 (P<0.05) and the decreased protein expression level of P62 in the hippocampus were also observed in the model group (P<0.05). Compared with the model group, the ligustrazine group had a significant increase in the number of neurons with ordered arrangement and an increase in Nissl bodies, significant reductions in the positive expression of PINK1 and Parkin, the apoptosis rate of neurons, and the protein expression levels of PINK1, Parkin, Beclin1, and LC3 (P<0.05), and a significant increase in the protein expression level of P62 (P<0.05).@*CONCLUSIONS@#Ligustrazine can alleviate hypoxic-ischemic brain damage and inhibit neuronal apoptosis in neonatal rats to a certain extent, possibly by inhibiting PINK1/Parkin-mediated autophagy.
Subject(s)
Rats , Animals , Hypoxia-Ischemia, Brain/metabolism , Animals, Newborn , Rats, Sprague-Dawley , Beclin-1 , Autophagy , Ubiquitin-Protein Ligases/metabolism , Protein Kinases/metabolismABSTRACT
ObjectiveTo observe the effects of Aurantii Fructus Immaturus， Atractylodis Macrocephalae Rhizoma， and their combination on slow transit constipation via PTEN-induced putative kinase 1 （PINK1）/Parkin pathway-mediated mitophagy. MethodFifty-six male SD rats were randomly assigned into normal group， model group， natural recovery group， Aurantii Fructus Immaturus group， Atractylodis Macrocephalae Rhizoma group， Aurantii Fructus Immaturus combined with Atractylodis Macrocephalae Rhizoma group， and mosapride group， with 8 rats in each group. Slow transit constipation model was established by gavage with loperamide （3 mg·kg-1·d-1） for 14 days in other groups except the normal group. After successful modeling， except that the model group was continuously induced by loperamide， the normal group and the natural recovery group were administrated with 0.9% normal saline by gavage， and the rats in the Aurantii Fructus Immaturus （1.35 g·kg-1·d-1） group， the Atractylodis Macrocephalae Rhizoma （2.7 g·kg-1·d-1） group， the Aurantii Fructus Immaturus combined with Atractylodis Macrocephalae Rhizoma （4.05 g·kg-1·d-1） group， and the mosapride （1.56 mg·kg-1·d-1） group were administrated with corresponding drugs by gavage for 7 days. The amount of feces， fecal water content， and intestinal propulsion rate of rats were determined. The pathological changes of the colon were evaluated by hematoxylin-eosin （HE） staining and Alcian blue-periodic acid-Schiff （AB-PAS） staining. The activity of respiratory chain complex and the ultrastructure of the colon tissue were determined by ultraviolet spectrophotometry and observed by transmission electron microscopy， respectively. Real-time fluorescence quantitative polymerase chain reaction（Real-time PCR） was employed to determine the mRNA levels of PINK1， Parkin， and p62， and Western blot to determine the protein levels of microtubule-associated protein 1 light chain 3 （LC3）， PINK1， and Parkin. ResultCompared with the normal group， the model group and the natural recovery group showed decreases in the amount of feces， fecal water content， intestinal propulsion rate （P<0.05，P<0.01）， and activities of mitochondrial respiratory chain complexes Ⅱ， Ⅲ， and Ⅳ in the colon tissue （P<0.05，P<0.01）. Further， the mRNA levels of PINK1 and Parkin and the protein levels of PINK1， Parkin， and LC3 were up-regulated （P<0.01） and the mRNA level of p62 was down-regulated in the model group （P<0.05） and the natural recovery group. Compared with the model group and the natural recovery group， the Aurantii Fructus Immaturus combined with Atractylodis Macrocephalae Rhizoma group showed increased amount of feces， fecal water content， intestinal propulsion rate， and activities of mitochondrial respiratory chain complexes Ⅱ， Ⅲ， and Ⅳ （P<0.05，P<0.01）. Moreover， the combination meliorated the degree of mitochondrial swelling in the colon tissue， down-regulated the mRNA levels of PINK1 and Parkin and the protein levels of PINK1， Parkin， and LC3 （P<0.05，P<0.01）， and up-regulated the mRNA level of p62 （P<0.05）. ConclusionAurantii Fructus Immaturus and Atractylodis Macrocephalae Rhizoma， and their combination may remedy the colonic motility disorders in rats with slow transit constipation by blocking PINK1/Parkin signaling pathway to inhibit the excessive mitophagy in interstitial cells of Cajal in the colon tissue.
ABSTRACT
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.
ABSTRACT
ObjectiveTo investigate the effects of Gandou decoction （GDD） on the mitophagy of hippocampal neurons in toxic milk （TX） mouse model of Wilson disease and explore the protective mechanism of GDD against neuron injury through the PTEN induced kinase 1 （Pink1） /E3 ubiquitin ligase （Parkin） pathway. MethodSixty mice were randomly divided into a blank group， a model group， a penicillamine group （0.09 g·kg-1）， and low- （5.5 g·kg-1）， medium- （11 g·kg-1）， and high-dose （22 g·kg-1） GDD groups， and treated correspondingly by gavage for 8 weeks. Morris water maze， traction test， and pole test were used for the evaluation of animal behaviors. Hematoxylin-eosin （HE） staining and transmission electron microscopy were used to observe cell apoptosis， ultrastructure， autophagy， and mitochondrial structure. The levels of superoxide dismutase （SOD）， reactive oxygen species （ROS）， and malondialdehyde （MDA） were detected by enzyme-linked immunosorbent assay （ELISA）. Real-time fluorescence-based quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of Pink1， Parkin， autophagy-associated protein Beclin-1， microtubule-associated protein 1 light chain 3Ⅱ （LC3Ⅱ）， and p62. Western blot was conducted to detect the protein expression of Pink1， Parkin， Beclin-1， LC3Ⅱ/Ⅰ， and p62. ResultCompared with the blank group， the model group showed prolonged escape latency， decreased times of platform crossing， lower score in the traction test， and longer pole climbing time （P<0.01）. Compared with the model group， the medium- and high-dose GDD groups and the penicillamine group showed shortened escape latencies， increased times of platform crossing， higher scores in the traction test， and shortened pole climbing time （P<0.01）. Compared with the blank group， the model group displayed severely damaged neurons and increased autophagosomes. Compared with the model group， the medium- and high-dose GDD groups and the penicillamine group showed improved neuron damage and reduced autophagosomes. The levels of ROS and MDA were higher and SOD was lower in the model group than those in the blank group （P<0.01）， while the levels of the above indicators were reversed by GDD intervention as compared with the model group （P<0.01）. Compared with the blank group， the model group exhibited up-regulated mRNA and protein expression of Pink1， Parkin， LC3Ⅱ， and Beclin-1 and down-regulated p62 （P<0.05）. Compared with the model group， the medium- and high-dose GDD groups showed reduced mRNA and protein expression of Pink1， Parkin， LC3Ⅱ， and Beclin-1 and increased p62 （P<0.05， P<0.01）. ConclusionGDD can significantly inhibit the excessive mitophagy in neurons of TX mice and protect neurons from damage. The mechanism may be related to the regulation of the Pink1/Parkin pathway.
ABSTRACT
Objective To investigate the expression of mitochondrial autophagy-associated protein PINK1 and Parkin in parotid pleomorphic adenoma (PA) and carcinoma ex pleomorphic adenoma(CA-EX-PA). Methods The expression of PINK1 and Parkin were detected by immunohistochemistry in 24 cases of normal parotid gland tissues, 32 cases of PA tissues and 42 cases of CA-EX-PA tissues. The correlations of PINK1 and Parkin expression with the clinicopathologic characteristics of CA-EX-PA patients were analyzed. Results The positive rates of PINK1 in normal parotid gland, PA and CA-EX-PA tissues were 100%, 91% and 67% respectively; and those of Parkin were 100%, 88% and 52% respectively. The expression rates of PINK1 and Parkin in PA and CA-EX-PA tissues were significantly lower than those in normal tissues (P < 0.05). The expression of PINK1 and Parkin protein were positively correlated in CA-EX-PA tissues (r=0.877, P < 0.01). In CA-EX-PA tissues, the expression of PINK1 and Parkin were associated with tumor invasion, lymph node metastasis and TNM stage (P < 0.05). Conclusion The expression of PINK1 and Parkin are decreased in PA and CA-EX-PA tissues. The decrease of mitochondrial autophagy activity might play important roles in the development, invasion and metastasis of parotid gland tumors.
ABSTRACT
Objective:To investigate the relationship between the mechanism of exogenous hydrogen sulfide (H 2S)-induced reduction of apoptosis in neurons during focal cerebral ischemia-reperfusion (I/R) and PINK1/Parkin pathway-mediated mitochondrial autophagy in rats. Methods:Two hundred and sixteen healthy male Sprague-Dawley rats, aged 6-8 weeks, weighing 250-270 g, were divided into 4 groups ( n=54 each) using a random number table method: control group (group C), I/R group, H 2S group and H 2S plus 3-methyladenine (3-MA) group (H 2S+ 3-MA group). Focal cerebral ischemia was induced by middle cerebral artery occlusion in anesthetized rats.In group H 2S+ 3-MA, 3-MA 10 mg/kg was intraperitoneally injected at 15 min before the onset of reperfusion, while the equal volume of normal saline was given instead in the other groups.In H 2S and H 2S+ 3-MA groups, 0.25% NaSH (a donor of exogenous H 2S) 10 mg/kg was intraperitoneally injected at the onset of reperfusion, while the equal volume of normal saline was given instead in the other groups.At 1, 3 and 7 days of reperfusion, neural function was scored, and corner test (the percentage of left turn was calculated) was performed.Brains were removed and brain tissues were obtained for determination of the cerebral infarct size, Bax, Bcl-2 and caspase-3 positive cells, cell apoptosis, and expression of mitophagy-related protein microtubule-associated protein 1 light chain 3 (LC3), PINK1 and Parkin (by Western blot). The percentage of cerebral infarct size, rate of Bax, Bcl-2 and caspase-3 positive cells and apoptosis rate were calculated.The ratio of LC3-Ⅱexpression to LC3-Ⅰexpression (LC3-Ⅱ/LC3-Ⅰ) was also calculated. Results:Compared with group C, the neural function score was significantly decreased, the percentage of left turn, percentage of cerebral infarct size, rate of Bax, Bcl-2 and caspase-3 positive cells, apoptosis rate of neurons, and LC3-Ⅱ/LC3-Ⅰ were increased, and the expression of PINK1 and Parkin was up-regulated at each time point of reperfusion in group I/R ( P<0.05). Compared with group I/R, the neural function score and rate of Bcl-2 positive cells were significantly increased, the percentage of left turn, percentage of cerebral infarct size, rate of Bax and caspase-3 positive cells, and apoptosis rate of neurons were decreased, the expression of PINK1 and Parkin was up-regulated, and LC3-Ⅱ/LC3-Ⅰ were increased at each time point of reperfusion in group H 2S ( P<0.05), and no significant change was found in the parameters mentioned above in group H 2S+ 3-MA ( P>0.05). Compared with group H 2S, the neural function score and rate of Bcl-2 positive cells were significantly decreased, the percentage of left turn, percentage of cerebral infarct size, rate of Bax and caspase-3 positive cells, and apoptosis rate of neurons were increased, the expression of PINK1 and Parkin was down-regulated, and LC3-Ⅱ/LC3-Ⅰ was decreased at each time point of reperfusion in H 2S+ 3-MA group ( P<0.05). Conclusion:The mechanism by which exogenous H 2S inhibits apoptosis in neurons during focal cerebral I/R is related to enhancing mitochondrial autophagy mediated by the PINK1/Parkin pathway in rats.
ABSTRACT
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.
ABSTRACT
OBJECTIVE@#To investigate the protective effects and mechanism of Chinese herbal compound Tongxinluo Capsule (, TXL) on the Parkin-mediated mitophagy and the ubiquitin-proteasome system in a rat model of myocardial ischemia-reperfusion injury (MIRI).@*METHODS@#Seventy adult male Sprague-Dawley rats were randomly divided into 7 groups: sham group, MIRI group, low- and high-dose TXL (0.5 and 1 g·kg@*RESULTS@#Compared with the sham group, the MIRI group exhibited a larger infarcted area (27.13%±0.01%, P<0.01), a higher apoptotic index (34.33%±2.03% vs.1.81%±0.03%, P<0.01), and higher cTnI expression (14.18±1.01 vs. 7.96±0.32, P<0.01). The mitochondrial integrity was damaged in the MIRI group, while TXL and ATV alleviated the damage of MIRI. More autophagosomes were observed in the high-dose TXL group than in the MIRI group (7.00±0.58 vs. 4.33±1.15, P<0.05). More amounts of PTEN-induced putative kinase protein 1 (PINK1) and Parkin translocated onto the mitochondria were detected in the high-dose TXL group than in the MIRI group (P<0.05). The ubiquitin response was signifificantly downregulated in the high-dose TXL group relative to the MIRI group (P<0.05). CQ administration abolished the activation of autophagy flux and the PINK1/ Parkin pathway induced by high-dose of TXL.@*CONCLUSIONS@#TXL ameliorates MIRI via activating Parkin-mediated mitophagy in rats. The downregulation of the ubiquitin-proteasome system is also involved.
ABSTRACT
Parkin, also known as PARK2, has been closely related to Parkinson's disease (PD) since its discovery. It is considered to be a neuroprotective gene. With the in-depth understanding for its structure, Parkin has been unveiled as an E3 ubiquitin ligase. Parkin is involved in the regulation of cell cycle, mitochondrial homeostasis, energy metabolism and other cellular processes, and is closely related to many diseases. It even plays completely opposite roles in the same pathway, namely cell proliferation and apoptosis, indicating that this must be a gene with an extremely broad and important role. This article summarizes the discovery and structure of Parkin and its self-inhibiting characteristics, focusing on the ubiquitination process that it participates in as E3 ubiquitin ligase and the resulting autophagy, protein degradation, changes in protein subcellular localization and protein interaction. These may all serve as the basis for Parkin to prevent PD and suppress tumors. On this basis, two reasons for Parkin abnormalities leading to PD are summarized: abnormal protein quality control and mitochondrial dysfunction, and extended to cardiovascular and kidney diseases caused by the abnormality of Parkin due to mitochondrial dysfunction. The internal connection between Parkin and cancer is also introduced from the aspects of Parkin as a tumor suppressor, regulating cell cycle, apoptosis and metastasis, oxidative stress and energy metabolism. By maintaining the active state of Parkin or enhancing its expression, it may be possible to improve the condition of PD patients. But the mechanism of Parkin's inhibition of tumor growth remains to be deciphered, and the potential role of Parkin in mediating the relationship between PD and cancer risk should be strengthened. These follow-up in-depth studies and their role in the diagnosis and treatment of related diseases and application of target molecules laid the foundation.
ABSTRACT
@#Given the opposing effects of Akt and AMP-activated protein kinase (AMPK) on metabolic homeostasis, this study examined the effects of deletion of Akt2 and AMPKα2 on fat diet-induced hepatic steatosis. Akt2–Ampkα2 double knockout (DKO) mice were placed on high fat diet for 5 months. Glucose metabolism, energy homeostasis, cardiac function, lipid accumulation, and hepatic steatosis were examined. DKO mice were lean without anthropometric defects. High fat intake led to adiposity and decreased respiratory exchange ratio (RER) in wild-type (WT) mice, which were ablated in DKO but not Akt2−/− and Ampkα2−/− mice. High fat intake increased blood and hepatic triglycerides and cholesterol, promoted hepatic steatosis and injury in WT mice. These effects were eliminated in DKO but not Akt2−/− and Ampkα2−/− mice. Fat diet promoted fat accumulation, and enlarged adipocyte size, the effect was negated in DKO mice. Fat intake elevated fatty acid synthase (FAS), carbohydrate-responsive element-binding protein (CHREBP), sterol regulatory element-binding protein 1 (SREBP1), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), peroxisome proliferator-activated receptor-α (PPARα), PPARγ, stearoyl-CoA desaturase 1 (SCD-1), phosphoenolpyruvate carboxykinase (PEPCK), glucose 6-phosphatase (G6Pase), and diglyceride O-acyltransferase 1 (DGAT1), the effect was absent in DKO but not Akt2−/− and Ampkα2−/− mice. Fat diet dampened mitophagy, promoted inflammation and phosphorylation of forkhead box protein O1 (FoxO1) and AMPKα1 (Ser485), the effects were eradicated by DKO. Deletion of Parkin effectively nullified DKO-induced metabolic benefits against high fat intake. Liver samples from obese humans displayed lowered microtubule-associated proteins 1A/1B light chain 3B (LC3B), Pink1, Parkin, as well as enhanced phosphorylation of Akt, AMPK (Ser485), and FoxO1, which were consolidated by RNA sequencing (RNAseq) and mass spectrometry analyses from rodent and human livers. These data suggest that concurrent deletion of Akt2 and AMPKα2 offers resilience to fat diet-induced obesity and hepatic steatosis, possibly through preservation of Parkin-mediated mitophagy and lipid metabolism.