[P3-2-22] Correlation between estrogen level and HSP70 expression in OVX rats
Keywords:OVXrat 、Salivary gland、aging
To determine whether the expression of HSP70, a repair-promoting protein in damaged cells, is affected by elevated estrogen levels, we continued the subject experiment on P. gingivalis uninfected rats in the present study and observed the level of tissue cell disruption in OVX rats given different estrogen levels. Nine-week-old female rats, 24 OVX and six sham were used. OVX rats were further divided into three subgroups which were given different estrogen sources and levels: regular food, food containing soy isoflavones, and β-estradiol pellet implants. After nine month, their mandibular central incisor gingiva and tongues were brushed with an electric toothbrush for one minute. Three hours after brushing, all rats were perfused. Mandibular and maxilla gums, tongues, and salivary glands were removed and prepared as frozen sections. HSP70 antibody was used as the labeling marker for repaired cells. Results showed HSP70 expression to be considerably more abundant in the salivary glands of OVX rats with implanted β-estradiol pellets, indicating more repair of cell damage occurred in rats with higher amounts of estrogen consumption. From these results alone, a strong correlation can be made between estrogen level and a body’s ability to repair damaged cells; however, HSP70 expression in sham rats, which should have the highest estrogen level of all groups, was unexpectedly lower than that in OVX rats with β-estradiol pellets. The timing of observation should be adjusted in our future experiment to reflect optimal maturity period when their estrogen levels are highest.