Mycoplasma Hyopneumoniae 168 And 168L Induce The Difference Of The Mitochondrial Pathway Of Apoptosis Of Porcine Tracheal Epithelial Cells

Mycoplasma hyopneumoniae (Mhp) is the pathogen of Mycoplasma Pneumoniae of Swine. The main symptoms of this disease are asthma and cough, with meat or shrimp-like consolidation in the leading edge of lobus cardiacus of lung as pathological features. The disease has high morbidity and low mortality.Aim at:In vitro study was conducted to explore the defference of apoptosis between the host cell apoptosis infected by Mhp 168L or Mhp 168.Methods and results:Key mitochondrial pathway of apoptotic markers like chromosome breakage, cytochrome c release, the loss of mitochondrial membrane potential, caspase-3 expression difference were also observed in all the groups. Firstly, we used 5×103CCU/cell concentration of Mhp 168 or Mhp 168L to infect PTEC, than using AO/EB double staining method to detect cell apoptosis rate after cultured for 12h, 18h,24h,30h, to determine the best time to infection. TUNEL detection of PTEC infected by Mhp 168 was observed positive cells, and the positive cells was significantly higher than the Mhp 168L infection group. It also through the analysis of flow cytometry using Annexin V-FITC and PI double staining, determined the optimal concentration and time of infection. Both caspase-8 and-12 activation were detected in apoptosis and haven’t found increased sign. Caspase-3 activation of Mhp 168 infection group was significantly high than Mhp 168L infection group. Cytosolic fraction cytochrome c was detected by immunofluorescence, fluorescence intensity of Mhp 168 infection group was higher than Mhp 168L infection group. JC-1 staining was used to detect mitochondrial membrane potential, green fluorescence intensity of Mhp 168 infection group was higher than Mhp 168L infection group. NAC pre-treatment significantly altered key apoptotic events like prevented cytochrome c release, loss of mitochondrial membrane potential and caspase-3 activation.Conclusions:Our results indicate that Mhp 168 and Mhp 168L turely induces apoptosis in PTEC cells through mitochondrial pathways.