HISTOLOGY AND HISTOPATHOLOGY

From Cell Biology to Tissue Engineering

 

Effects of estrogen on STIM1/Orai1 in the sublingual gland of ovariectomized rats

Yun Bai1,2, Bing Li1, Sinan Wang1, Hai Jiang3, Junlei Li4, Wenjuan Wang3, Ke Wang3, Lihua Qin3 and Jing Jia1,5

1Shanxi Medical University School and Hospital of Stomatology, Taiyuan, 2Department of Stomatology, Tianjin Hospital, Tianjin, 3Department of Anatomy and Histoembryology, School of Basic Medical Science, Peking University, 4Department of Cardiology, Peking University People's Hospital and 5Department of Stomatology, The Third Medical Center, Chinese PLA (People's Liberation Army) General Hospital, Beijing, China

Offprint requests to: Lihua Qin, Department of Anatomy and Histoembryology, School of Basic Medical Science, Peking University, Beijing, China. e-mail: qinlihua88@163.com and Jing Jia, Department of Stomatology, The Third Medical Center, Chinese PLA (People's Liberation Army) General Hospital, Beijing 100039, China. e-mail: jiajing1996@aliyun.com


Summary. Background. Studies have shown that estrogen can protect the function of the sublingual gland, but the specific mechanism is still unclear. Besides, the STIM1/Orai1 pathway is important to secretion in the salivary gland. Here, we explore the possible effects of estrogen on sublingual gland function by observing changes of STIM1 and Orai1 levels in the sublingual glands of ovariectomized rats. Methods. 42 adult female Sprague-Dawley rats were randomly divided into three groups: SHAM, OVX, and OVX+E (n=14 per group). Two weeks after ovariectomy, rats were treated with estrogen (β-estradiol). The expression of STIM1 and Orai1 in the sublingual gland were observed by double label-immunohistochemistry and immunofluorescence. Calcium imaging was conducted to observe changes in cellular Ca2+ levels. Results. IHC and IF showed that the levels of both STIM1 and Orai1 decreased following ovariectomy, but increased to SHAM levels after estrogen treatment. By IF, STIM1 and Orai1 exhibited perfect co-localization. Calcium imaging results showed that the Ca2+ in the cells decreased after ovariectomy. Estrogen intervention returned levels of these proteins and Ca2+ to the same as those in the control group. Conclusion. This study demonstrates that low estrogen status significantly reduced the expression of STIM1 and Orai1 in the sublingual gland of rats, along with cellular Ca2+ levels. These data provide insight into the likely mechanisms underlying sublingual gland secretion dysfunction during menopause. Histol Histopathol 35, 701-707 (2020)

Key words: STIM1, Orai1, Sublingual gland, Estrogen, Ovariectomized rats

DOI: 10.14670/HH-18-198