Melanin extract from Gallus gallus domesticus promotes proliferation and differentiation of osteoblastic MG-63 cells via bone morphogenetic protein-2 signaling

BACKGROUND/OBJECTIVES: Gallus gallus domesticus (GD) is a natural mutant breed of chicken in Korea with an atypical characterization of melanin in its tissue. This study investigated the effects of melanin extracts of GD on osteoblast differentiation and inhibition of osteoclast formation. MATERIALS/METHODS: The effects of the melanin extract of GD on human osteoblast MG-63 cell differentiation were examined by evaluating cell viability, osteoblast differentiation, and expression of osteoblast-specific transcription factors such as bone morphogenetic protein 2 (BMP-2), small mothers against decapentaplegic homologs 5 (SMAD5), runt-related transcription factor 2 (RUNX2), osteocalcin and type 1 collagen (COL-1) by reverse transcription-polymerase chain reaction and western blotting analysis. We investigated the inhibitory effect of melanin on the osteoclasts formation through tartrate-resistant acid phosphatase (TRAP) activity and TRAP stains in Raw 264.7 cell. RESULTS: The melanin extract of GD was not cytotoxic to MG-63 cells at concentrations of 50-250 µg/mL. Alkaline phosphatase (ALP) activity and bone mineralization of melanin extract-treated cells increased in a dose-dependent manner from 50 to 250 µg/mL and were 149% and 129% at 250 µg/mL concentration, respectively (P < 0.05). The levels of BMP-2, osteocalcin, and COL-1 gene expression were significantly upregulated by 1.72-, 4.44-, and 2.12-fold in melanin-treated cells than in the control cells (P < 0.05). The levels of RUNX2 and SMAD5 proteins were higher in melanin-treated cells than in control vehicle-treated cells. The melanin extract attenuated the formation of receptor activator of nuclear factor kappa-B ligand-induced TRAP-positive multinucleated RAW 264.7 cells by 22%, and was 77% cytotoxic to RAW 264.7 macrophages at a concentration of 500 µg/mL. CONCLUSIONS: This study provides evidence that the melanin extract promoted osteoblast differentiation by activating BMP/SMADs/RUNX2 signaling and regulating transcription of osteogenic genes such as ALP, type I collagen, and osteocalcin. These results suggest that the effective osteoblastic differentiation induced by melanin extract from GD makes it potentially useful in maintaining bone health.

Effect of bushen tiaojing recipe on the expressions of Smad1, Smad5, Smad8, and Smad4 in human mural granulosa cells / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the effect of Bushen Tiaojing Recipe (BTR) on the expressions of drosophila mothers against decapentaplegic protein (Smadl), Smad5, Smad8, and Smad4 on human mural granulosa cells.</p><p><b>METHODS</b>Sixty-six patients undergoing in vitro fertilization-embryo transfer (IVF-ET) were randomly assigned to two groups in the ratio of 1:2, the treatment group and the control group. Twenty-three patients in the treatment group were treated with BTR and GnRHa/FSH/hCG, while forty-three patients in the control group were treated with GnRHa/FSH/hCG. The mRNA expressions of Smad1, Smad5, Smad8, and Smad4 on mural granulosa cells of the mature follicle were detected by real-time PCR on the ovum retrieval day. The expressions of Smad1, Smad5, Smad8, and Smad4 at the protein level were observed using cell immunofluorescence method.</p><p><b>RESULTS</b>The mRNA and protein expressions of Smadl in the granulosa cells were significantly higher in the treatment group than in the control group (P <0.05). There was no statistical difference in the mRNA and protein expressions of Smad5, Smad8, and Smad4 between the two groups.</p><p><b>CONCLUSION</b>The mechanisms of BTR for improving the pregnancy rate and the ovarian functions might be correlated with up-regulating mRNA and protein expressions of Smadl of human mural granulosa cells.</p>

Expression of Smad1 and Smad5 in the testis of infertile rats with kidney-yang deficiency / 中华男科学杂志

<p><b>OBJECTIVES</b>To study the expression of Smad1 and Smad5 in the testis of infertile rats with adenine-modeled kidney-yang deficiency and the pathological mechanism of infertility with kidney-yang deficiency, attempting to obtain experimental evidence for the prevention and treatment of male infertility.</p><p><b>METHODS</b>Forty-eight 60 d male SD rats were divided randomly into 6 groups with 8 in each: 7 d, 14 d and 21 d kidney-yang deficiency groups, and 7 d, 14 d and 21 d control groups. The experimental rats had been fed with adenine (300 mg/kg) and the expression levels of Smad1 and Smad5 were measured with immunohistochemical SABC method at the 7th, 14th and 21st day.</p><p><b>RESULTS</b>Smad1 immunoreactivity was mainly located in the spermatogonia, spermatocytes and spermatids, and the reactive substance distributed in cytoplasm with negative nuclei. Sertoli cells and Leydig cells were negative. Compared with the control, the expression level of Smad1 was decreased significantly at the 21st day (P < 0.05), but with no significant difference at the 7th and 14th day (P > 0.05). Smad5 immunoreactivity was mainly located in the spermatogonia and spermatocytes, and the reactive substance distributed in cytoplasm with negative nuclei. Compared with the control, the expression level of Smad5 was not significantly different at the 7th day (P > 0.05). The expression of Smad5 was negative at the 14th and the 21st day.</p><p><b>CONCLUSION</b>The weaker expression of Smad1 and no expression of Smad5 may be one of the pathological mechanisms of infertility with adenine-modeled kidney-yang deficiency.</p>