title: Thyroid dysfunction, either hyper or hypothyroidism, promotes gallstone formation by different mechanisms.
abstract: We have investigated comprehensively the effects of thyroid function on gallstone formation in a mouse model. Gonadectomized gallstone-susceptible male C57BL/6 mice were randomly distributed into three groups each of which received an intervention to induce hyperthyroidism, hypothyroidism, or euthyroidism. After 5 weeks of feeding a lithogenic diet of 15% (w/w) butter fat, 1% (w/w) cholesterol, and 0.5% (w/w) cholic acid, mice were killed for further experiments. The incidence of cholesterol monohydrate crystal formation was 100% in mice with hyperthyroidism, 83% in hypothyroidism, and 33% in euthyroidism, the differences being statistically significant. Among the hepatic lithogenic genes, Trβ was found to be up-regulated and Rxr down-regulated in the mice with hypothyroidism. In contrast, Lxrα, Rxr, and Cyp7α1 were up-regulated and Fxr down-regulated in the mice with hyperthyroidism. In conclusion, thyroid dysfunction, either hyperthyroidism or hypothyroidism, promotes the formation of cholesterol gallstones in C57BL/6 mice. Gene expression differences suggest that thyroid hormone disturbance leads to gallstone formation in different ways. Hyperthyroidism induces cholesterol gallstone formation by regulating expression of the hepatic nuclear receptor genes such as Lxrα and Rxr, which are significant in cholesterol metabolism pathways. However, hypothyroidism induces cholesterol gallstone formation by promoting cholesterol biosynthesis.
authors.affiliation: Department of Thyroid Surgery, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Cancer Institute, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Yu
authors.affiliation: Department of Thyroid Surgery, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China.
authors.forename: Qun-Zi
authors.initials: QZ
authors.lastname: Zhao
authors.affiliation: Cancer Institute, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China.
authors.forename: Shu
authors.initials: S
authors.lastname: Zheng
authors.affiliation: Department of Clinical Medicine, School of Medicine, Zhejiang University, Hangzhou 310029, China.
authors.forename: Wen-Jie
authors.initials: WJ
authors.lastname: Qing
authors.affiliation: Department of Clinical Medicine, School of Medicine, Zhejiang University, Hangzhou 310029, China.
authors.forename: Chun-di
authors.initials: CD
authors.lastname: Miao
authors.affiliation: Department of Clinical Medicine, School of Medicine, Zhejiang University, Hangzhou 310029, China.
authors.forename: Jaiswal
authors.initials: J
authors.lastname: Sanjay
mesh_terms: D000818:Animals; D001835:Body Weight; D002784:Cholesterol / Q000097:blood; D042882:Gallstones / Q000209:etiology* / Q000473:pathology; D006980:Hyperthyroidism / Q000150:complications*; D007037:Hypothyroidism / Q000150:complications*; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D013963:Thyroid Hormones / Q000097:blood
chemical_list: D013963:Thyroid Hormones; D002784:Cholesterol
keywords: C57BL/6 mice; Cholesterol gallstone; Hepatic lithogenic genes; Hyperthyroidism; Hypothyroidism