Matrine and baicalin inhibit apoptosis induced by Panton-Valentine leukocidin of Staphylococcus aureus in bovine mammary epithelial cells

Abstract

It was previously thought that the Panton-Valentine leukocidin (PVL) toxin of Staphylococcus aureus (S. aureus) was not the main cause of cow mastitis. However, in recent years, detection of the gene encoding PVL has been increasing in dairy cow mastitis, which implies that PVL may be related to bovine mastitis. Therefore, we wanted to search for drugs inhibiting PVL or PVL-induced apoptosis. In this report, we investigated the apoptosis mechanism of PVL in bovine mammary epithelial cells (BMEC) and the inhibition mechanism of matrine and baicalin on PVL-induced apoptosis of BMEC. The results demonstrated that BMEC were damaged and underwent apoptosis by a standard PVLproducing strain of S. aureus (ATCC 49775), a PVL knockout mutant Δpvl 49775, complemented mutant C-Δpvl 49775, or recombinant (r)PVL in vitro. The rates of apoptosis and necrosis induced by S. aureus ATCC 49775 and C-Δpvl 49775 were significantly higher than those induced by Δpvl 49775, demonstrating that BMEC apoptosis and necrosis were associated with PVL. In addition, this research found matrine and baicalin could inhibit the apoptosis of BMEC induced by PVL-producing S. aureus and by rPVL. Matrine downregulated protein expression levels of endogenous and exogenous cleaved caspase-3, cleaved caspase-8, and cleaved caspase-9, and the effect was pronounced at a concentration of 50 μg/mL. Baicalin downregulated the expression of cleaved caspase-9. These results suggested that matrine and baicalin may have potential value against cow mastitis caused by the toxin PVL.

Anti-Staphylococcus aureus Single-Chain Fragment Variables Play a Protective Anti-Inflammatory Role In Vitro and In Vivo

“…The number of apoptotic cells and necrotic cells in scFv treatment groups decreased approximately by half (from 1300 to 750 in USA300 group (p < 0.01), from 1240 to 640 in ATCC25923 group (p < 0.01) and from 1590 to 860 in XD69 group (p < 0.01), respectively) compared with that of the NC group. Previous studies demonstrated that Panton-Valentine leucocidin and enterotoxin H of S. aureus could induce apoptosis of bovine mammary epithelial cells [60,61].…”

A Systematic Review of the Pharmacology, Toxicology and Pharmacokinetics of Matrine

“…In recent years, it has been reported that the Panton-Valentine leukocidin (PVL) toxin of Staphylococcus aureus may be related to the pathogenic mechanism of bovine mastitis. Jia et al found that MT inhibited PVL-induced apoptosis of bovine mammary epithelial cells (BMEC) by down-regulating the expression of cleaved caspase-3, cleaved caspase-8, and cleaved caspase-9 proteins (Jia et al, 2020). Furthermore, a subinhibitory concentration of MT inhibited the Staphylococcus aureus secretion of a-hemolysin in a none dose-dependent manner, thus reducing the inflammatory damage of a-hemolysininduced BMEC cells (Feng et al, 2018).…”

Astragalus polysaccharides and astragaloside IV alleviate inflammation in bovine mammary epithelial cells by regulating Wnt/β-catenin signaling pathway

“…BMECs were preserved in our laboratory, the cell line (BMECs) was obtained from Shandong Agricultural University, Tai’an, China [ 22 ]. BMECs were incubated in Dulbecco’s modified Eagle’s medium (DMEM) (Biological Industries, Israel) supplemented with 10% FBS (v/v) (Gibco, Waltham, MA, USA), 5 μg/mL insulin (Sigma-Aldrich, St. Louis, MO, USA), 5 μg/mL transferrin (Sigma-Aldrich), 1 μg/mL hydrocortisone (Sigma-Aldrich), 1 μg/mL corporin (Sigma-Aldrich), and 100 U/mL penicillin-streptomycin (Sigma-Aldrich) in an environment of 5% CO 2 and 95% air at 37°C.…”

“…Fluorescent quantitative PCR was performed according to the procedure described in the ChamQ Universal SYBR qPCR Master Mix kit (Vazyme). The 2- ΔΔCq method was used to analyze the expression of target genes, and β-actin was used as an internal reference [ 22 ]. Primer design for qPCR is shown in Table 2 [ 22 ].…”

“…The 2- ΔΔCq method was used to analyze the expression of target genes, and β-actin was used as an internal reference [ 22 ]. Primer design for qPCR is shown in Table 2 [ 22 ].…”