title: Water soluble bioactives of nacre mediate antioxidant activity and osteoblast differentiation.
abstract: 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.
authors.affiliation: Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, India.
authors.forename: Ratna
authors.initials: R
authors.lastname: Chaturvedi
authors.affiliation: Department of Pathology, University of Texas Health Science Center, San Antonio, Texas, United States of America.
authors.forename: Prajjal Kanti
authors.initials: PK
authors.lastname: Singha
authors.affiliation: Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, India.
authors.forename: Satyahari
authors.initials: S
authors.lastname: Dey
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D052160:Benzothiazoles / Q000737:chemistry; D001688:Biological Products / Q000737:chemistry / Q000494:pharmacology*; D001713:Biphenyl Compounds / Q000737:chemistry; D002113:Calcification, Physiologic / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects* / Q000528:radiation effects; D002460:Cell Line; D024042:Collagen Type I / Q000235:genetics; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D015227:Lipid Peroxidation / Q000187:drug effects / Q000528:radiation effects; D051379:Mice; D060734:Nacre / Q000737:chemistry*; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D015675:Osteocalcin / Q000235:genetics; D010012:Osteogenesis / Q000187:drug effects; D010851:Picrates / Q000737:chemistry; D012995:Solubility; D013451:Sulfonic Acids / Q000737:chemistry; D014158:Transcription, Genetic / Q000187:drug effects / Q000528:radiation effects; D014466:Ultraviolet Rays / Q000009:adverse effects; D014867:Water / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D052160:Benzothiazoles; D001688:Biological Products; D001713:Biphenyl Compounds; D024042:Collagen Type I; D060734:Nacre; D010851:Picrates; D013451:Sulfonic Acids; D014867:Water; D015675:Osteocalcin; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D006861:Hydrogen Peroxide; C004931:1,1-diphenyl-2-picrylhydrazyl; D000469:Alkaline Phosphatase