Expression patterns of inflammatory and oxidative stress-related genes in the uterine and ovarian tissues of dogs diagnosed with pyometra based on cervical patency status

Abstract

This study aimed to investigate the expression patterns of genes associated with inflammation and oxidative stress in ovarian and uterine tissues of dogs with pyometra, categorized by cervical status (open cervix or closed cervix), which influences disease severity. The control group comprised healthy animals undergoing elective ovariohysterectomy. Tissue inflammatory gene expression and Malondialdehyde (MDA) levels were determined while microbial and histopathological examinations were conducted, along with immunohistochemical evaluations. In the closed-cervix group, uterine TNF and IL6 were upregulated approximately 10-fold while IL10 was upregulated nearly 5-fold. TNF expression differed remarkably between the pyometra groups. In the closed-cervix group, PTGS2 and HMOX1 were upregulated approximately 5-fold whereas NFE2L2 expression was downregulated. The closed-cervix group also had the highest uterine MDA levels. Regarding ovarian tissue, MDA levels were higher in the closed-cervix group than in the open-cervix group while IL10 expression was lower in the closed-cervix group than the open-cervix group. In the closed-cervix group, NFE2L2 was downregulated whereas HMOX1 was upregulated. Uterine TNF levels were positively correlated with IL6, IL10, PTGS2, and HMOX1, but negatively correlated with NFE2L2. IL6 was positively correlated with IL10, PTGS2, and HMOX1. NFE2L2 was negatively correlated with IL6 and HMOX1. IL10 was positively correlated with PTGS2 and HMOX1. MDA was positively correlated with TNF, IL6, IL10, PTGS2, NFE2L2, and HMOX1. TNF levels were positively correlated with ovarian PTGS2, and with IL6 and NFE2L2. MDA was positively correlated with PTGS2 and HMOX1. MDA could be an important biomarker for understanding the severity of pyometra. Moreover, TNF expression and its relationships with various studied parameters such as IL10 may contribute to treatment and prognostic biomarker studies in closed-cervix pyometra pathology.