Rosiglitazone affects the progression of surgically-induced endometriosis in a rat model

Endometriosis is closely associated with inflammatory reactions and angiogenesis. Whether PPARγ is a target for the treatment of endometriosis remains unknown. The present study was designed to investigate the impact of a PPARγ agonist (rosiglitazone, RSG) on endometriosis in a rat model and to identify the underlying mechanism. The endometriosis model was established in rats. The pathological state of the endometrium was examined using hematoxylin-eosin staining. The microstructures of interest were visualized using electron microscopy. Western blot analysis and reverse transcription-quantitative polymerase chain reaction were used to detect PPARγ and MAT2A expression. VEGF and caspase-3 expression were investigated using immunohistochemistry. Pathological analysis revealed transparent and red nodules in the model group, and that vasoganglions were present all over the nodules. Endometrial epithelial hyperplasia was observed in the model group, and the shape was columnar. Increased interstitial cell numbers, with compact structure and abundant blood supply, were detected in the model group. Compared with the model group, incomplete epithelial structures with sparse interstitial cells and loose structure were observed in the pathological images from RSG treatment groups. Numerous inflammatory cells and poor blood supply were observed in the endometrial tissues, and the gland was filled mostly with vacuolar cells. Electron microscopy revealed that the tissue structure was integrated. Many vacuoles were formed within the endometrial tissue and the classical morphological changes of apoptotic cells were observed in RSG-treated groups. Caspase-3 and PPARγ expression increased and expression of VEGF and MAT2A decreased in RSG-treated groups. Taken together, these results revealed that RSG impacts the development and progression of endometriosis likely by inhibiting angiogenesis and inducing apoptosis.