The pathogenesis of canine pyometra is multifactorial, involving hormonal imbalances, aberrant immune responses, and metabolic dysregulation includes lipid metabolism and oxidative stress. This study focuses on lipid metabolism and oxidative stress, revealing the key regulatory role of AMPK and PLIN2 in canine pyometra. Bitches with open cervix pyometra (n:8) and healthy bitches undergoing elective ovariohysterectomy (n:4) were enrolled to the study. In experiment one, the serum and tissue levels of Malondialdehyde (MDA) and Superoxide Dismutase (SOD) activity were assessed. Additionally, uterine histopathological analysis, AMPK and PLIN2 expressions were determined through immunohistochemistry. Furthermore, inflammation, oxidative stress, and lipid metabolism-related factors were evaluated using Western blot analysis. In experiment two, primary cell cultures were prepared from healthy uterine endometrial cells of the dogs in control group. Cultured canine endometrial epithelial cells were treated with lipopolysaccharide (LPS) along with oleic acid (OA) to induce an inflammatory response. Tissue and serum MDA and SOD levels were greater in dogs with pyometra. Accumulated lipid droplets were observed in the uterine tissue of bitches with pyometra. The phosphorylation of AMPK and the expression of PLIN2 significantly increased in the pyometra group. The expression of related lipid synthesis proteins such as ACC1, FASN, SREBP-1c, and PLIN2 was upregulated, while PPARα and PGC1α were downregulated in bitches with pyometra. In experiment two, activation of AMPK and PLIN2 not only restores the expression of PGC1α, but also effectively alleviates inflammation and oxidative stress. The role of lipid metabolism and oxidative stress in canine pyometra is elucidated, thus contributing to the pathogenesis of pyometra in dogs.
