Objective: To study the effects of vibration on the expression of mitochondrial fusion and fission genes and ultrastructure of skeletal muscle in rabbits. Methods: Thirty-two 3.5-month-old New Zealand rabbits were randomly divided into low-intensity group, medium-intensity group, high-intensity group and control group, with 8 rabbits in each group. The rabbits in the experimental group were subjected to hind limb vibration load test for 45 days. The vibration intensity of the high intensity group was 12.26 m/s(2), the medium intensity group was 6.13 m/s(2), and the low intensity group was 3.02 m/s(2) according to the effective value of weighted acceleration[a(hw (4))] for 4 hours of equal energy frequency. The control group was exposed to noise only in the same experimental environment as the medium-intensity group. The noise levels of each group were measured during the vibration load experiment. After the test, the mRNA expression of mitochondrial fusion gene (Mfn1/Mfn2) and fission gene (Fis1, Drp1) by RT-PCR in the skeletal muscles were measured and the ultrastructure of the skeletal muscles were observed in high intensity group. Results: The mRNA expression of mitochondrial in the skeletal muscle tissues of control group, low intensity group, medium intensity group and high intensity group were Mfn1: 3.25±1.36, 3.85±1.90, 4.53±2.31 and 11.63±7.68; Mfn2: 0.68±0.25, 1.02±0.40, 0.94±0.33 and 1.40±0.45; Fis1: 1.05±0.62, 1.15±0.59, 1.53±1.06 and 2.46±1.51 and Drp1: 3.72±1.76, 2.91±1.63, 3.27±2.01 and 4.21±2.46, respectively. Compared with the control group, the expressions of Mfn1 mRNA, Mfn2 mRNA and Fis1 mRNA in the high-intensity group increased significantly (P<0.05) , and the expressions of Mfn2 mRNA in the medium-intensity group and the low-intensity group increased significantly (P<0.05) . Compared with the control group, the ultrastructure of skeletal muscle of high intensity group showed mitochondrial focal accumulation, cristae membrane damage, vacuole-like changes; Z-line irregularity of muscle fibers, and deficiency of sarcomere. Conclusion: Vibration must be lead to the abnormal mitochondrial morphology and structure and the disorder of energy metabolism due to the expression imbalance of mitochondrial fusion and fission genes in skeletal muscles of rabbits, which may be an important target of vibration-induced skeletal muscle injury.
Animals ; Hindlimb/metabolism* ; Mitochondria/metabolism* ; Mitochondrial Dynamics ; Mitochondrial Proteins/pharmacology* ; Muscle, Skeletal ; Rabbits ; Vibration/adverse effects*

Apoptosis Regulatory Proteins ; Apoptosis ; Antiviral Agents/pharmacology* ; Mitochondrial Proteins ; Cell Line, Tumor ; Antineoplastic Agents/pharmacology*

OBJECTIVETo investigate the differentially expressed mitochondrial proteins in hydroxycamptothecin (HCPT)-treated SMMC-7721 cells by comparative proteomic analysis.

METHODSApoptosis of SMMC-7721 cells were induced by using HCPT and their mitochondria were isolated with a mitochondria isolation kit for cultured cells. Three different solubility protein fractions were extracted with ReadyPrep Sequential Extraction Kit and were separated by two-dimensional gel electrophoresis (2-DE). PDQuest software was used to differentiate mitochondrial proteins between control cells and HCPT-treated cells. Matrix assisted laser desorption/ionization time of flying mass spectrometry (MALDI-TOF-MS) was used to identify some of the different proteins.

RESULTSHighly purified mitochondria and high resolution 2-DE patterns of the proteins were obtained. Forty-four mitochondrial protein spots from the HCPT-treated cells showed different expressions compared to those of the control cells. Twenty of the different protein spots were analyzed by MALDI-TOF-MS.

CONCLUSIONDifferently expressed mitochondrial proteins in HCPT-treated cells and control cells were obtained in this study. This will be of help to understand the mechanism by which HCPT induces cell apoptosis.

Antineoplastic Agents, Phytogenic ; pharmacology ; Camptothecin ; analogs & derivatives ; pharmacology ; Cell Line, Tumor ; Humans ; Membrane Potentials ; drug effects ; Mitochondrial Proteins ; metabolism ; Proteomics

OBJECTIVETo study effects of three pentacyclic triterpenoids, oleanolic acid (OA), ursolic acid (UA) and asiatic acid (AA) on Ca(2+)-induced liver mitochondrial permeability transition (MPT).

METHODEffects of three compounds on liver MPT induced by Ca2+ were assessed by measuring the change in mitochondrial swelling, mitochondrial membrane potential and release of matrix Ca2+ in vitro.

RESULTObvious mitochondrial swelling, loss of mitochondrial membrane potential and release of matrix Ca2+ occurred after the addition of 50 micromol x L(-1) Ca2+. However, preincubation with 50 mg x L(-1) OA, UA or AA significantly blocked the above changes. In addition, it was also found that there are differences in the inhibitions of three compounds on liver MPT induced by Ca2+.

CONCLUSIONThree pentacyclic triterpenoids, OA, UA and AA, have significant mitochondrial protection through blocking on liver MPT and the inhibition on liver MPT of AA is stronger than that of UA and OA.

Animals ; Calcium ; metabolism ; pharmacology ; Membrane Potential, Mitochondrial ; drug effects ; Mice ; Mice, Inbred ICR ; Mitochondria, Liver ; drug effects ; metabolism ; Mitochondrial Membrane Transport Proteins ; drug effects ; Mitochondrial Swelling ; drug effects ; Pentacyclic Triterpenes ; pharmacology

Objective: To investigate the effect of arsenic and its main metabolites on the apoptosis of human lung adenocarcinoma cell line A549 and the expression of pro-apoptotic genes Bad and Bik. Methods: In October 2020, A549 cells were recovered and cultured, and the cell viability was detected by the cell counting reagent CCK-8 to determine the concentration and time of sodium arsenite exposure to A549. The study was divided into NaAsO(2) exposure groups and metobol: le expoure groups: the metabolite comparison groups were subdivided into the control group, the monomethylarsinic acid exposure group (60 μmol/L) , and the dimethylarsinic acid exposure group (60 μmol/L) ; sodium arsenite dose groups were subdivided into 4 groups: control group (0) , 20, 40, 60 μmol/L sodium arsenite NaAsO(2). Hoechst 33342/propidium iodide double staining (Ho/PI) was used to observe cell apoptosis and real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression levels of Bad and Bik mRNA in cells after exposure. Western blotting was used to detect the protein expressions of Bad, P-Bad-S112, Bik, cleaved Bik and downstream proteins poly ADP-ribose polymerase PARP1 and cytochrome C (Cyt-C) , using spectrophotometry to detect the activity changes of caspase 3, 6, 8, 9. Results: Compared with the control group, the proportion of apoptotic cells in the 20, 40, and 60 μmol/L NaAsO(2) dose groups increased significantly (P<0.01) , and the expression levels of Bad, Bik mRNA, the protein expression levels of Bad, P-Bad-S112, Bik, cleaved Bik, PARP1, Cyt-C were increased (all P<0.05) , and the activities of Caspase 3, 6, 8, and 9 were significantly increased with significantly differences (P<0.05) . Compared with the control group, the expression level of Bad mRNA in the DMA exposure group (1.439±0.173) was increased with a significant difference (P=0.024) , but there was no significant difference in the expression level of Bik mRNA (P=0.788) . There was no significant differences in the expression levels of Bad and Bik mRNA in the poison groups (P=0.085, 0.063) . Compared with the control group, the gray values of proteins Bad, Bik, PARP1 and Cyt-C exposed to MMA were 0.696±0.023, 0.707±0.014, 0.907±0.031, 1.032±0.016, and there was no significant difference between the two groups (P=0.469, 0.669, 0.859, 0.771) ; the gray values of proteins Bad, Bik, PARP1 and Cyt-C exposed to DMA were 0.698±0.030, 0.705±0.022, 0.908±0.015, 1.029±0.010, and there was no difference between the two groups (P=0.479, 0.636, 0.803, 0.984) . Conclusion: Sodium arsenite induces the overexpression of Bad and Bik proteins, initiates the negative feedback regulation of phosphorylated Bad and the degradation of Bik, activates the downstream proteins PARP1, Cyt-C and Caspase pathways, and mediates the apoptosis of A549 cells.
A549 Cells ; Adenosine Diphosphate Ribose/pharmacology* ; Apoptosis ; Apoptosis Regulatory Proteins ; Arsenic ; Arsenites ; Cacodylic Acid/pharmacology* ; Caspase 3 ; Caspases/pharmacology* ; Cytochromes c/pharmacology* ; Humans ; Mitochondrial Proteins/pharmacology* ; Poisons ; Propidium/pharmacology* ; RNA, Messenger ; Sincalide/pharmacology* ; Sodium Compounds ; bcl-Associated Death Protein/metabolism*

OBJECTIVETo study the apoptotic effect and mechanisms of methylmercury (MeHg) on HL-7702 cell line in vitro.

METHODSIn this study, the cell apoptosis was observed by AO/EB method and FCM method; the mitochondrial membrane potential was detected by FCM; and the expression of proteins related to apoptosis was measured by immunocytochemical method.

RESULTSAfter exposure to MeHg for 24 h in different doses, apoptotic rate ascended with the increasing of MeHg concentration. By AO/EB method, cell apoptotic ratio of negative control group was (2.62 +/- 0.19)%, cell apoptotic ratio of 10-50 micromol/L exposure groups were (7.97 +/- 0.64)%, (12.66 +/- 0.76)%, (19.16 +/- 0.87)%, (18.42 +/- 0.88)%, and (11.52 +/- 0.63)%, there were significant differences between the exposure and negative control groups (q values were 17.057, 32.009, 52.732, 50.373, 28.375; P<0.05). Mitochondrial membrane potential descended with the increase of MeHg, mitochondrial membrane potential of negative control group was (10.23 +/- 3.43) mV, mitochondrial membrane potential of 10-50 micromol/L exposure groups were (3.25 +/- 0.66), (3.03 +/- 0.35), (1.68 +/- 1.26), (1.69 +/- 1.13) and (1.77 +/- 0.88) mV, and there was significant differences between exposure and negative control groups (q values were 9.569, 9.871, 11.722, 11.708, 11.598; P<0.05). The expression of Bax, Bcl-2, CytC, Caspase-3 and AIF enhanced with the increase of MeHg, Bax/Bcl-2 ratio also appeared a trend of increase. Bax expression integral optical density (IOD) of negative control group was (21295.86 +/- 1969.81), Bax expression IOD of 10, 20, 30 micromol/L groups were 42807.87 +/- 4416.64, 55651.65 +/- 4662.72, and 72708.56 +/- 910.10, there were significant differences in Bax expression between 10, 20, 30 micromol/L groups and negative control group (q values were 14.191, 14.320, 33.917; P<0.05); Bcl-2 expression IOD of negative control group was (12588.33 +/- 4091.02), Bcl-2 expression IOD of 10, 20, 30 micromol/L groups were 20539.16 +/- 4906.09, 23689.97 +/- 2281.42, and 28692.80 +/- 4655.86, there were significant differences in Bcl-2 expression between 10, 20, 30 micromol/L groups and negative control group (q values were 4.322, 6.035, 8.754; P<0.05); and AIF expression IOD of negative control group was (12942.72 +/- 457.94), AIF expression IOD of 10, 20, 30, 40 micromol/L groups were 16973.57 +/- 1922.87, 29998.91 +/- 6803.58, 52467.16 +/- 1916.25 and 106342.53 +/- 1273.19, there were significant differences in AIF expression between 20, 30 and 40 micromol/L groups and negative control group (q values were 11.449, 26.530, 62.692; P<0.05).

CONCLUSIONMeHg could induce apoptosis on HL-7702 cell line in vitro. The mechanisms could be related to mitochondrial pathway in apoptosis.

Apoptosis ; drug effects ; Cell Line ; Flow Cytometry ; Hepatocytes ; cytology ; drug effects ; Humans ; Membrane Potential, Mitochondrial ; drug effects ; Methylmercury Compounds ; pharmacology ; Mitochondrial Proteins ; metabolism

OBJECTIVETo investigate the effects of resveratrol (Res) on mitochondrial opening and Ca(2+)-induced Ca(2+) release (CICR) from rat liver cell mitochondria mediated by Ca(2+).

METHODSWistar rat liver cell mitochondria was extracted and Res-induced mitochondrial swelling was assessed spectrophotometrically at 540 nm to examine the permeability transition pore (PTP) opening. The membrane potential changes of Res-treated mitochondria were measured with fluorescence spectrophotometery. Ca(2+) uptake and release by the mitochondria was determined by absorbance change of arsenazo III at 685-675 nm monitored by dual wavelength spectrophotometry.

RESULTSRes promoted Ca(2+)-mediated PTP opening, and this effect was completely inhibited by CsA and lowered by trifluoperazine. CICR accelerated by Res treatment was completely blocked by ruthenium red and partly by trifluoperazine.

CONCLUSIONRes can promote PTP opening by inducing CICR, which may be one of the pathways that Res induces cell apoptosis.

Animals ; Calcium ; metabolism ; Cells, Cultured ; Female ; Hepatocytes ; cytology ; metabolism ; Mitochondria, Liver ; drug effects ; metabolism ; Mitochondrial Membrane Transport Proteins ; metabolism ; Mitochondrial Swelling ; drug effects ; Rats ; Rats, Wistar ; Stilbenes ; pharmacology

The aim of this study was to investigate the effect of edaravone (Eda) on the balance of mitochondrial fusion and fission in Parkinson's disease (PD) cell model. A cell model of PD was established by treating PC12 cells with 500 μmol/L 1-methyl-4-phenylpyridinium (MPP). Thiazole blue colorimetry (MTT) was used to detect the effect of different concentrations of Eda on the survival rate of PC12 cells exposed to MPP. The mitochondrial morphology was determined by laser confocal microscope. Western blot was used to measure the protein expression levels of mitochondrial fusion- and fission-related proteins, including OPA1, MFN2, DRP1 and Fis1. The results showed that pretreatment with different concentrations of Eda antagonized MPP-induced PC12 cell damage in a dose-dependent manner. The PC12 cells treated with MPP showed mitochondrial fragmentation, up-regulated DRP1 and Fis1 protein expression levels, and down-regulated MFN2 and OPA1 protein expression levels. Eda could reverse the above changes in the MPP-treated PC12 cells, but did not affect Fis1 protein expression. These results suggest that Eda has a protective effect on the mitochondrial fusion disruption induced by MPP in PC12 cells. The mechanism may be related to the up-regulation of OPA1/MFN2 and down-regulation of DRP1.
1-Methyl-4-phenylpyridinium ; Animals ; Dynamins ; Edaravone ; pharmacology ; GTP Phosphohydrolases ; Mitochondria ; drug effects ; Mitochondrial Dynamics ; Mitochondrial Proteins ; PC12 Cells ; Parkinson Disease ; Rats ; Up-Regulation

Wuzi-Yanzong-Wan (WZYZW) is a classic prescription for male infertility. Our previous investigation has demonstrated that it can inhibit sperm apoptosis via affecting mitochondria, but the underlying mechanisms are unclear. The purpose of the present study was to explore the actions of WZYZW on mitochondrial permeability transition pore (mPTP) in mouse spermatocyte cell line (GC-2 cells) opened by atractyloside (ATR). At first, WZYZW-medicated serum was prepared from rats following oral administration of WZYZW for 7 days. GC-2 cells were divided into control group, model group, positive group, as well as 5%, 10%, 15% WZYZW-medicated serum group. Cyclosporine A (CsA) was used as a positive control. 50 μmol·L^-1 ATR was added after drugs incubation. Cell viability was assessed using CCK-8. Apoptosis was detected using flow cytometry and TUNEL method. The opening of mPTP and mitochondrial membrane potential (MMP) were detected by Calcein AM and JC-1 fluorescent probe respectively. The mRNA and protein levels of voltage-dependent anion channel 1 (VDAC1), cyclophilin D (CypD), adenine nucleotide translocator (ANT), cytochrome C (Cyt C), caspase 3, 9 were detected by RT-PCR (real time quantity PCR) and Western blotting respectively. The results demonstrated that mPTP of GC-2 cells was opened after 24 hours of ATR treatment, resulting in decreased MMP and increased apoptosis. Pre-protection with WZYZ-medicated serum and CsA inhibited the opening of mPTP of GC-2 cells induced by ATR associated with increased MMP and decreased apoptosis. Moreover, the results of RT-qPCR and WB suggested that WZYZW-medicated serum could significantly reduce the mRNA and protein levels of VDAC1 and CypD, Caspase-3, 9 and CytC, as well as a increased ratio of Bcl/Bax. However, ANT was not significantly affected. Therefore, these findings indicated that WZYZW inhibited mitochondrial mediated apoptosis by attenuating the opening of mPTP in GC-2 cells. WZYZW-medicated serum inhibited the expressions of VDAC1 and CypD and increased the expression of Bcl-2, which affected the opening of mPTP and exerted protective and anti-apoptotic effects on GC-2 cell induced by ATR.
1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine ; Animals ; Atractyloside/pharmacology* ; Cyclophilin D ; Male ; Matrix Metalloproteinases ; Mice ; Mitochondrial Membrane Transport Proteins/metabolism* ; Mitochondrial Permeability Transition Pore ; RNA, Messenger ; Rats

OBJECTIVE: To explore the protective effect and possible mechanisms of bloodletting acupuncture at Jing-well points (BAJP) pre-treatment on acute hypobaric hypoxia (AHH)-induced myocardium injury rat. METHODS: Seventy-five rats were randomly divided into 5 groups by a random number table: a control group (n=15), a model group (n=15), a BAJP group (n=15), a BAJP+3-methyladenine (3-MA) group (n=15), and a BANA (bloodletting at nonacupoint; tail bleeding, n=15) group. Except for the control group, the AHH rat model was established in the other groups, and the corresponding treatment methods were adopted. Enzyme-linked immunosorbent assay (ELISA) was used to detect creatine kinase isoenzyme MB (CK-MB) and cardiac troponins I (CTnI) levels in serum and superoxide dismutase (SOD) and malondialdehyde (MDA) levels in myocardial tissue. Hematoxylin-eosin (HE) staining was used to observe myocardial injury, and terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) staining was used to observe cell apoptosis. Transmission electron microscopy detection was used to observe mitochondrial damage and autophagosomes in the myocardium. The mitochondrial membrane potential of the myocardium was analyzed with the fluorescent dye JC-1. Mitochondrial respiratory chain complex (complex I, III, and IV) activities and ATPase in the myocardium were detected by mitochondrial respiratory chain complex assay kits. Western blot analysis was used to detect the autophagy index and hypoxia inducible factor-1α (HIF-1α)/Bcl-2 and adenovirus E1B 19k Da-interacting protein 3 (BNIP3) signaling. RESULTS: BAJP reduced myocardial injury and inhibited myocardial cell apoptosis in AHH rats. BAJP pretreatment decreased MDA levels and increased SOD levels in AHH rats (all P<0.01). Moreover, BAJP pretreatment increased the mitochondrial membrane potential (P<0.01), mitochondrial respiratory chain complex (complexes I, III, and IV) activities (P<0.01), and mitochondrial ATPase activity in AHH rats (P<0.05). The results from electron microscopy demonstrated that BAJP pretreatment improved mitochondrial swelling and increased the autophagosome number in the myocardium of AHH rats. In addition, BAJP pretreatment activated the HIF-1α/BNIP3 pathway and autophagy. Finally, the results of using 3-MA to inhibit autophagy in BAJP-treated AHH rats showed that suppression of autophagy attenuated the treatment effects of BAJP in AHH rats, further proving that autophagy constitutes a potential target for BAJP treatment of AHH. CONCLUSION BAJP is an effective treatment for AHH-induced myocardial injury, and the mechanism might involve increasing HIF-1α/BNIP3 signaling-mediated autophagy and decreasing oxidative stress.
Animals ; Rats ; Acupuncture Therapy ; Altitude ; Apoptosis ; Autophagy ; Bloodletting ; Hypoxia/metabolism* ; Membrane Proteins/pharmacology* ; Mitochondrial Proteins/pharmacology* ; Oxidative Stress ; Rats, Sprague-Dawley