Serum levels of 17β-estradiol in ovariectomized rats fed young-coconut-juice and its effect on wound healing

Abstract

Department of Neuroscience and Anatomy, The Penn State University College of Medicine, P.O. Box 850, 500 University Drive Hershey, PA, 17033-0850, USA Exogenous estrogens such as 17β-estradiol (E2) can lower the risk of dementia in postmenopausal women (PMS), but can also increase the risk of serious side effects. Estrogen can, however, promote wound healing in ovariectomized rats and in PMS women. Phytoestrogen (PE) derived from plants might be a safer alternative source of estrogen for use in hormone replacement therapy (HRT). Young coconut juice (YCJ), Cocos nucifera (Arecaceae), that is believed to contain PE and other sex hormone-like substances, was therefore investigated for its possible beneficial effects on accelerating wound healing in ovariectomized rats, a model system for the postmenopausal condition. Sixty ovariectomized (ovx) rats were devided into 6 groups, 10 rats per group, group 1 received E2 (i.p.) at 2.5 μg/kgBW/day (control); groups 2 and 3 received YCJ at 20 mL and 100mL/kg BW/day, respectively. Group 4 received YCJ 100 mL/kg BW plus E2 at 2.5 μg/kg BW/ day twice a week, all for 5 weeks. The other two groups were ovx and sham-operated controls receiving vehicle, Milli Q water, like the rest, everyday once a day. Using a chemiluminescent immuno assay, circulating E2 in the ovariectomized group fed with YCJ at 100 mL/kg BW/day was not significantly different from the control group. Circulating E2 was lowest in the ovariectomized rats fed with 100 mL/kg BW of YCJ plus 2.5 μg/kg BW E2 twice a week. This finding indicates an antagonist effect of estrogen-like hormones in YCJ that competes with estradiol for the estrogen receptors. In these experiments, we noted that wound healing was significantly accelerated in ovariectomized rats receiving 100 mL YCJ/kg BW/day compared with any other groups.