| First Author | Wu N | Year | 2017 |
| Journal | FASEB J | Volume | 31 |
| Issue | 10 | Pages | 4305-4324 |
| PubMed ID | 28634212 | Mgi Jnum | J:253394 |
| Mgi Id | MGI:6108489 | Doi | 10.1096/fj.201700097R |
| Citation | Wu N, et al. (2017) Prolonged darkness reduces liver fibrosis in a mouse model of primary sclerosing cholangitis by miR-200b down-regulation. FASEB J 31(10):4305-4324 |
| abstractText | Melatonin therapy or prolonged exposure to complete darkness reduces biliary hyperplasia and liver fibrosis in bile-duct-ligated (BDL) rats; however, no information exists in primary sclerosing cholangitis (PSC). Thus, we aimed to determine the therapeutic effects of prolonged dark therapy or melatonin administration on hepatic fibrosis in the multidrug resistance gene 2-knockout (Mdr2(-/-)) mouse model of PSC. Melatonin levels, biliary mass, liver fibrosis, angiogenesis and miR-200b expression were evaluated in wild-type and Mdr2(-/-) mice exposed to darkness or melatonin treatment or in male patients with PSC and healthy controls. Mdr2(-/-) mice were also treated with miR-200b inhibitor or control before evaluating biliary mass, liver fibrosis, and angiogenesis. After overexpression of arylalkylamine N-acetyltransferase (AANAT; the enzyme regulating melatonin synthesis) or inhibition of miR-200b in cholangiocytes and hepatic stellate cells in vitro, we evaluated angiogenesis and fibrosis gene expression. After exposure to darkness or administration of melatonin, Mdr2(-/-) mice show elevated serum melatonin levels and inhibition of biliary mass, along with reduction of liver fibrosis and angiogenesis. MicroRNA PCR analysis demonstrated that miR-200b expression increased in Mdr2(-/-) mice and patients with PSC compared with controls and decreased in Mdr2(-/-) mice subjected to dark exposure or melatonin treatment. Inhibition of miR-200b in Mdr2(-/-) ablates biliary proliferation, liver fibrosis, and angiogenesis. In vitro, overexpression of AANAT or inhibition of miR-200b in cholangiocytes and hepatic stellate cells decreased the expression of miR-200b, angiogenesis, and fibrosis genes. Dark therapy or targeting melatonin/miR-200b axis may be important in the management of biliary damage and liver fibrosis in cholangiopathies including PSC.-Wu, N., Meng, F., Zhou, T., Han, Y., Kennedy, L., Venter, J., Francis, H., DeMorrow, S., Onori, P., Invernizzi, P., Bernuzzi, F., Mancinelli, R., Gaudio, E., Franchitto, A., Glaser, S., Alpini G. Prolonged darkness reduces liver fibrosis in a mouse model of primary sclerosing cholangitis by miR-200b down-regulation. |
