Abstract
Decreased salivary secretion and diminished taste sensation are common symptoms in female at menopause or after surgical ovariectomy at any age. The aim of the study is to investigate the histological, immunohistochemical and molecular changes of the submandibular gland in a rat model of menopause and the possible protective effect of combined coenzyme Q10 and estrogen compared to estrogen therapy alone. Fifty adult female rats were used. They were classified into 5 equal groups: negative control (I), positive control receiving coenzyme Q10 (II), ovariectomized (III), ovariectomized and received estrogen (IV) as well as ovariectomized and received both estrogen and coenzyme Q10 (V). After 8 weeks the submandibular glands were dissected out for histological and a SMA immunohistochemical assessment. SMP-30 gene expression was also carried out. Moreover, measurement of lipid peroxidation product and total antioxidant capacity were done. The study revealed that ovariectomy induces oxidative stress of the submandibular gland in the form of increased oxidative stress markers, decreased SMP-30 mRNA gene expression, increased optical density of a SMA and ultrastructure degenerative changes. Slight improvement of these results is observed in estrogen treated group. In contrary, nearly complete recovery is noticed in combined estrogen and coenzyme Q10 treated group. We concluded that ovariectomy could induce submandibular gland cellular senescence and oxidative stress dependent histological changes. Estrogen has a protective role but combined coenzyme Q10 and estrogen therapy could have a better effect in prevention and protection against ovariectomy induced submandibular gland damage.