<p>Antagonistic Effects Of Baicalin On <em>Mycoplasma gallisepticum</em>-Induced Inflammation And Apoptosis By Restoring Energy Metabolism In The Chicken Lungs</p>

Abstract

BackgroundBaicalin possesses potential anti-inflammatory, anti-tumor and anti-oxidant activities. In the present study, we attempted to investigate the preventive effects of baicalin against Mycoplasma gallisepticum (MG)-induced inflammation, apoptosis and energy metabolism dysfunction in chicken lungs.MethodsExperimental chickens were randomly divided into 1) control group, 2) MG infection group, 3) MG-infected group treated with baicalin at a dose of 450 mg/kg and 4) baicalin alone treated group (450 mg/kg). After 7 days of post-treatment, serum and lung tissues were collected for different experimental analyses. The hallmarks of inflammation, apoptosis and energy metabolism dysfunction were detected by histological and ultrastructural examination, qRT-PCR, Western blotting and terminal deoxynucleotidyl transferase-mediated dUTP nick endlabeling (TUNEL) assay.ResultsThe level of serum inflammatory markers were increased with MG infection. Histological and ultrastructural analysis showed excessive inflammatory cells infiltrates, alveolar wall thickening, hemorrhages, mitochondrial and nuclear damage, including mitochondrial swelling and condensation of DNA in the lungs of chickens infected with MG. TUNEL assay positive-stained nuclei were significantly increased in MG infection group. In addition, the mRNA and protein expression level of energy metabolism-related genes and ATPase activities were significantly reduced. Meanwhile, MG-induced morphological and ultrastructural changes were partially disappeared with baicalin-treatment, and the level of serum inflammatory markers were significantly reduced. It has been noted that baicalin significantly attenuated MG-induced inflammation and apoptosis in the chicken lungs through the suppression of nuclear factor-kappa B and reduced extensive positive-stained apoptotic nuclei. More importantly, ATPase activities and mRNA and protein expression level of energy metabolism-related genes were significantly improved with baicalin-treatment in the lungs of chickens infected with MG.ConclusionConclusively, it has been suggested from these results that baicalin-treatment efficiently prevented MG-induced inflammation, apoptosis and energy metabolism dysfunction in the chicken lungs and provide basis for new therapeutic targets to control MG infection.

Baicalin attenuated Mycoplasma gallisepticum‐induced immune impairment in chicken bursa of fabricius through modulation of autophagy and inhibited inflammation and apoptosis

“…These results are consistent with the results of apoptosis which proved that MG infection causing the depletion of CD8 + cells might be due to apoptosis. Our previous studies also revealed that MG induced apoptosis in chicken lungs and spleen 36,59 . Hence, we speculate that the depletion of CD8 + cells in chicken BF could be the possible cause of immune impairment during MG infection.…”

“…Baicalin treatment was started after 3 days of challenge. Baicalin powder was first dissolved in distilled water and given orally once a day as mentioned previously 36 . Chickens were sacrificed after 7 days of baicalin post‐treatment and BF samples were collected for experimental analyses.…”

“…DNA fragmentation was detected by TUNEL staining in tissue section which is a standard technique for the detection of apoptosis. Three sections were randomly chosen and positive cells were counted under a fluorescence microscope after anti‐fluorescence quenching in visual fields (magnification field (×400)) as described previously 36 …”

Current status of vaccine research, development, and challenges of vaccines for Mycoplasma gallisepticum

“…Previous reports showed that factors such as high feeding density, heat and/cold stresses, excessive ammonia, accumulation of feces, fouling of the chicken house, excessive temperature differences, and sudden changes in climate can contribute to the spread and outbreak of disease ( Hochachka and Dhondt, 2000 ; Ley, 2003 ). Mycoplasma gallisepticum infection caused major economic losses in terms of reduced weight gain, egg production and hatchability, downgrading carcass quality, and the infected birds become susceptible to other diseases ( Beaudet et al., 2017 ; Ishfaq et al., 2019a ). Mycoplasma gallisepticum is a continuing problem in poultry and efforts to prevent the losses in commercial flocks particularly in layer and breeders including bacterin-based vaccines, killed vaccines, and live vaccines.…”

Baicalin inhibits inflammation caused by coinfection of Mycoplasma gallisepticum and Escherichia coli involving IL-17 signaling pathway

“…Baicalin suppressed inflammation mainly through suppression of toll-like receptors and nuclear factor kappa-B (NF-κB) pathway ( Ming et al., 2018 ). Earlier studies explained that baicalin interacted with various signaling pathways and ameliorated MG-induced inflammation in chicken thymus ( Li et al., 2019 ), spleen ( Ishfaq et al., 2019a ), DF-1 cells ( Wu et al., 2019a ) and lungs ( Ishfaq et al., 2019b ). In addition, baicalin proved effective against E. coli or LPS-induced inflammation in various experimental animals ( Nagaki et al., 2001 ; Cheng et al., 2017 ; Zhao et al., 2018 ).…”