Chaturvedi Ratna, Singha Prajjal Kanti, Dey Satyahari
Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, India.
Department of Pathology, University of Texas Health Science Center, San Antonio, Texas, United States of America.
PLoS One. 2013 Dec 19;8(12):e84584. doi: 10.1371/journal.pone.0084584. eCollection 2013.
The water soluble matrix of nacre is a proven osteoinductive material. In spite of the differences in the biomolecular compositions of nacre obtained from multiple species of oysters, the common biochemical properties of those principles substantiate their biological activity. However, the mechanism by which nacre stimulates bone differentiation remains largely unknown. Since the positive impact of antioxidants on bone metabolism is well acknowledged, in this study we investigated the antioxidant potential of a water soluble matrix (WSM) obtained from the nacre of the marine oyster Pinctada fucata, which could regulate its osteoblast differentiation activity. Enhanced levels of ALP activity observed in pre-osteoblast cells upon treatment with WSM, suggested the induction of bone differentiation events. Furthermore, bone nodule formation and up-regulation of bone differentiation marker transcripts, i.e. collagen type-1 and osteocalcin by WSM confirmed its ability to induce differentiation of the pre-osteoblasts into mature osteoblasts. Remarkably, same WSM fraction upon pre-treatment lowered the H2O2 and UV-B induced oxidative damages in keratinocytes, thus indicating the antioxidant potential of WSM. This was further confirmed from the in vitro scavenging of ABTS and DPPH free radicals and inhibition of lipid peroxidation by WSM. Together, these results indicate that WSM poses both antioxidant potential and osteoblast differentiation property. Thus, bioactivities associated with nacre holds potential in the development of therapeutics for bone regeneration and against oxidative stress induced damages in cells.
珍珠母的水溶性基质是一种经证实的骨诱导材料。尽管从多种牡蛎中获得的珍珠母在生物分子组成上存在差异，但这些成分的共同生化特性证实了它们的生物活性。然而，珍珠母刺激骨分化的机制在很大程度上仍不清楚。由于抗氧化剂对骨代谢的积极影响已得到充分认可，在本研究中，我们研究了从海洋牡蛎马氏珠母贝的珍珠母中获得的水溶性基质（WSM）的抗氧化潜力，它可以调节其成骨细胞分化活性。用WSM处理前成骨细胞后观察到碱性磷酸酶（ALP）活性水平升高，提示骨分化事件的诱导。此外，WSM诱导骨结节形成并上调骨分化标志物转录本，即I型胶原蛋白和骨钙素，证实了其诱导前成骨细胞分化为成熟成骨细胞的能力。值得注意的是，预处理后的相同WSM组分降低了H2O2和UV-B诱导的角质形成细胞氧化损伤，从而表明WSM具有抗氧化潜力。WSM对ABTS和DPPH自由基的体外清除以及对脂质过氧化的抑制进一步证实了这一点。总之，这些结果表明WSM具有抗氧化潜力和成骨细胞分化特性。因此，与珍珠母相关的生物活性在开发骨再生治疗药物和对抗细胞氧化应激诱导的损伤方面具有潜力。
