Viburnum opulus L.: A remedy for the treatment of endometriosis demonstrated by rat model of surgically-induced endometriosis

Abstract

Ethnopharmacological relevance: Endometriosis is a gynecological disorder characterized by the presence of endometrial tissue outside the uterine cavity. The fruits of Viburnum opulus L. have been used to treat gynecological disorders including primary and secondary dysmenorrhea and ovarian cysts.

Materials and methods: Air-dried and powdered fruits of V. opulus were extracted sequentially with n-hexane, ethyl acetate (EtOAc), and methanol (MeOH), respectively for four days. Endometriosis was induced by suturing 15mm piece of endometrium into abdominal wall of Sprague Dawley rats. In second laparotomy, the dimensions of endometrial implants were measured and intra-abdominal adhesions were scored. The abdomen was closed. Extracts were daily administered to the rats. At the end of the experiment, rats were sacrified and endometriotic foci areas and intra-abdominal adhesions were re-evaluated. The tissues were also histopathologically investigated. Furthermore, tumor necrosis factor-α (TNF-α), vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) levels of peritoneal fluid were measured. HPLC analyses were conducted on the most potent EtOAc and MeOH extracts to determine the amount of the major compound, chlorogenic acid.

Results: The endometriotic volumes were found to be reduced significantly in the EtOAc extract-administered group to 30.1mm³ and in the MeOH extract-administered group to 34.7mm³ as compared to the control group. No adhesion was observed in the reference and EtOAc groups. Histopathological data also supported the results. Both EtOAc and MeOH extract-administered groups displayed significant remission in the levels of TNF-α, VEGF and IL-6. When the active extracts were subjected to HPLC analysis, chlorogenic acid was found to be the major compound and the amount of this compound was calculated as 0.5112±0.0012mg and 1.7072±0.0277mg/100mg extract, repectively.

Conclusions: The results of the present study indicate that the effectiveness of the fruit extract of V. opulus could be partially attributed chlorogenic acid. Other phenolic compounds could potentiate the activity due to their amount.

Keywords: Cytokine; Experimental endometriosis model; Rat; Viburnum opulus.