Prototheca zopfii genotype II induces mitochondrial apoptosis in models of bovine mastitis

Abstract

Prototheca zopfii is an alga increasingly isolated from bovine mastitis. of the two genotypes of P. zopfii (genotype i and ii (Gt-i and-ii)), P. zopfii Gt-ii is the genotype associated with acute mastitis and decreased milk production, although its pathogenesis is not well known. the objective was to determine inflammatory and apoptotic roles of P. zopfii Gt-ii in cultured mammary epithelial cells (from cattle and mice) and murine macrophages and using a murine model of mastitis. Prototheca zopfii Gt-ii (but not Gt-i) invaded bovine and murine mammary epithelial cells (Mecs) and induced apoptosis, as determined by the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling assay. this P. zopfii Gt-ii driven apoptosis corresponded to mitochondrial pathways; mitochondrial transmembrane resistance (ΔΨm) was altered and modulation of mitochondrionmediated apoptosis regulating genes changed (increased transcriptional Bax, cytochrome-c and Apaf-1 and downregulated Bcl-2), whereas caspase-9 and-3 expression increased. Apoptotic effects by P. zopfii Gt-ii were more pronounced in macrophages compared to Mecs. in a murine mammary infection model, P. zopfii GT-II replicated in the mammary gland and caused severe inflammation with infiltration of macrophages and neutrophils and upregulation of pro-inflammatory genes (TNF-α, IL-1β and Cxcl-1) and also apoptosis of epithelial cells. thus, we concluded P. zopfii Gt-ii is a mastitis-causing pathogen that triggers severe inflammation and also mitochondrial apoptosis.

Klebsiella pneumoniae infection causes mitochondrial damage and dysfunction in bovine mammary epithelial cells

“…Under various pathological conditions, mitochondria often undergo several morphological changes, including swelling, hyperplasia, hypertrophy and increased density of the mitochondrial matrix [27]. In this study, there was severe mitochondrial swelling and vacuolation, as well as mitochondrial rupture and degenerate cristae after K. pneumoniae infection, consistent with a previous study [28] and providing morphological evidence of mitochondrial damage.…”

“…A change in mitochondrial membrane potential can reflect the permeability of mitochondrial inner membrane, an indicator of mitochondrial function and damage. Furthermore, a decreased mitochondrial inner membrane potential can induce apoptosis [ 27 ]. Perhaps the reduction in MMP was due to a primary effect of an unknown Klebsiella virulence factor.…”

Effect of heat stress on udder health of dairy cows

“…Beyond these ‘mainstream’ pathogens, other organisms like Prototheca spp., Arcanobacterium pyogenes , Mycoplasma , Aerococcus viridans , Corynebacterium bovis , Trueperella pyogenes , Nocardia cyriacigeorgica and yeast have a considerable impact on clinical mastitis incidence (Liu et al ., 2015; Alkasir et al ., 2016; Chen et al ., 2017; Tomazi et al ., 2018; Shahid et al ., 2020). In a recent study in southeastern Poland, Jagielski et al .…”

Protothecosis in humans and animals

“…W odpowiedzi na kontakt z patogenem komórki te inicjują zapalną odpowiedź immunologiczną. Po naruszeniu mechanizmów obronnych nabłonka glony Prototheca mogą atakować makrofagi, powodując, iż patogen staje się bardziej niedostępny dla antybiotyków i trudniej wykryć go metodami diagnostycznymi [44,45]. Mastitis u krów spowodowane przez glony Prototheca spp.…”