Histopathological investigation of the effects of trastuzumab on the uterus in a rat model with endometriosis

It was aimed to investigate histopathological effects of trastuzumab on the uterus in a rat model with experimentally induced endometriotic tissue in the present study. In this study, 28 female Wistar albino rats (10-12 weeks old, 250-280 g) were divided into 4 groups (n =7). After a 7-day acclimation period, rats in the estrous phase were selected. The control group received no endometriosis induction; fat tissue was attached to the peritoneum and the abdomen was sutured. The endometriosis group underwent surgical induction of endometriosis using an auto-transplantation method, where uterine horn fragments were sutured to the peritoneum and mesentery. After a 4-week recovery period, the lesion size was measured, but no treatment was given. The endometriosis+Trastuzumab group received the same induction procedure as the endometriosis group, followed by intraperitoneal administration of trastuzumab (5 mg/kg) for 4 weeks. The trastuzumab group had no endometriosis induction but received the same trastuzumab dosage and schedule. Every animal tissue sample was obtained, and histopathological analysis was performed. In histopathological analysis, there was a significant difference between the Endometriosis group which had the most severe pathological changes compared to the control group (p<0.01). As well as; Endometriosis+Trastuzumab groups showed significant improvement in terms of epithelial integrity (p<0.05), Mast cell infiltration (p<0.01), glandular degeneration (p<0.05), and fibrosis (p0.05). Trastuzumab treatment resulted in protective effects on endometriosis-affected uterine tissue. In this context, histopathological results suggested that trastuzumab may be beneficial in treating damage caused by experimentally induced endometriosis.