Olea europaea subsp. Cuspidata and Juniperus procera hydroalcoholic leaves' extracts modulate stress hormones in stress-induced cystitis in rats

Objective: To study the effect of Saudi medicinal plant in stress-induced cystitis in experimental rats. Materials and Methods: Seventy-two female Sprague Dawley rats (200–250 g) were divided into eight groups of 9 rats each. Group 1 and 2 are controls assigned nonstressed and stressed, respectively. Other six groups received different treatments for 2 weeks. After the 14 days of treatment, each group was exposed to water-immersion restraint stress (WIRS) for 30 min. Blood samples were collected to measure the corticotropin-releasing hormone (CRH) and adrenocorticotropic hormone (ACTH) levels. The rats were sacrificed, and their urinary bladders were isolated immediately for a histological and immunohistochemical examination. Results: Rats exposed to WIRS had lesions in the urinary bladder, with a significant increase in plasma CRH and ACTH levels in comparison to the nonstressed controls. Bladder cut sections in stressed rats showed no gross structural abnormality in smooth muscle and connective tissue ratio. There were noticeable variations in mast cell (MC) infiltration and activity with a loss of more than 20% of cellular staining and a significant increase in the number of red blood cell-filled blood vessels. Our findings showed that supplementation of Olea europaea leaf extract (OEE) or Juniperus procera leaf extract (JPE) reduced the MC infiltration and significantly reduced stress hormones compared to the stressed controls. Conclusions: The present study demonstrated that OEE/JPE alone and their combination have a potential protective effect against stress-induced cystitis in rats. The underlying mechanism of the present study also resulted in a decrease in CRH and ACTH stress hormones.