MiR-183 regulates the differentiation of osteoblasts in the development of osteoporosis by targeting Smad4.

OBJECTIVE: To discuss the effect of miR-183 on osteoblast differentiation in the osteoporosis progression via targeting Smad4. METHODS: Osteoporosis models were constructed on ovariectomized (OVX) mice to determine the expression of miR-183 and Smad4. Then, MC3T3-E1 cells and primary osteoblasts were divided into Mock, miR-control, miR-183 mimic, miR-183 inhibitor, siSmad4 and miR-183 inhibitor + siSmad4 groups. Alkaline phosphatase (ALP) staining were performed to determine ALP activity, alizarin red staining to evaluate the calcium deposit, while qRT-PCR and Western blotting were used to determine the expression of related molecules. Besides, MC3T3-E1 cells transfected with miR-control or miR-183 mimic were cultured with or without TGF-ß1 to verify whether miR-183 regulates the TGF-ß signaling pathway. RESULTS: MiR-183 was up-regulated with decreased Smad4 in the femur of OVX mice, and dual luciferase reporter gene assay showed that Smad4 was a target of miR-183. As compared to Mock group, MC3T3-E1 cells and primary osteoblasts in the miR-183 mimic group and siSmad4 group had significant reductions of OCN, OPN, Runx2 and Osx, as well as decreased ALP activity and calcium deposit. Contrarily, miR-183 and Smad4 were up-regulated and down-regulated respectively. However, cells in the miR-183 inhibitor group manifested the opposite changes. Besides, osteoblast differentiation in the miR-183 inhibitor + siSmad4 group was weakened evidently when compared to miR-183 inhibitor group. Pathway analysis indicated that miR-183 regulated osteogenic differentiation via TGF-ß signaling pathway. CONCLUSION: MiR-183 was up-regulated in osteoporosis, and miR-183 overexpression can inhibit osteoblast differentiation by targetedly down-regulating TGF-ß pathway member Smad4 to trigger osteoporosis.

[The transplantation of latissimus dorsi flap of the base of T shape artery with the pedicle of the thoracodorsal artery].

OBJECTIVE: To explore the possibility that the free latissimus dorsi musculo-cutaneous flap to repair the forearm leg wound. METHODS: To design latissimus dorsi musculo-cutaneous flap which is foundation on T form thoracodorsal artery stalk. To set the short arm into the receiver artery break and anastomos them. It is not only reassure the blood of free musculo-cutaneous flap, but also reconstruct the continuation of the receiver main artery. RESULTS: In 16 patients, 15 patients success completely, 1 patient main success. The blood supply of receiver is adequate. CONCLUSIONS: The free T form thoracodorsal artery stalk musculo-cutaneous flap free grafting is a good method to repair the skin and soft tissues defection of forearm and leg.