Masaya Yamamoto

klotho is an aging suppressor gene and extends life span when overexpressed in mice. Klotho protein was recently demonstrated to function as a hormone that inhibits insulin/insulin-like growth factor-1 (IGF-1) signaling. Here we show that Klotho protein increases resistance to oxidative stress at the cellular and organismal level in mammals. Klotho protein activates the FoxO forkhead transcription factors that are negatively regulated by insulin/IGF-1 signaling, thereby inducing expression of ma

To develop a carrier for the controlled release of biologically-active growth factors, biodegradable hydrogels were prepared through glutaraldehyde cross-linking of gelatin with isoelectric points (IEP) of 5.0 and 9.0, i.e. 'acidic' and 'basic' gelatins, respectively. Radioiodinated growth factors were used to investigate their sorption and desorption from the hydrogel of both types of gelatin. Basic fibroblast growth factor (bFGF) and transforming growth factor-beta1 (TGF-beta1) were well sorbe

The objective of this study is to investigate the feasibility of a biodegradable hydrogel of gelatin as the controlled release carrier of bone morphogenetic protein-2 (BMP-2) suitable for enhancement of bone regeneration at a segmental bone defect. Hydrogels with three different water contents were prepared through glutaraldehyde crosslinking of gelatin with an isoelectric point of 9.0 under varied reaction conditions. Segmental critical-sized defects (20 mm) were created at the ulnar bone of sk

Biodegradable hydrogels were prepared from gelatin by glutaraldehyde cross-linking for release matrix of recombinant human bone morphogenetic protein-2 (BMP-2). BMP-2 solution was impregnated into the dried hydrogels to prepare BMP-2-incorporating gelatin hydrogels. In the in vitro study, enhanced retention of BMP-2 was observed from the BMP-2-incorporating gelatin hydrogels after an initial burst of BMP-2 incorporated initially in the hydrogel. Following subcutaneous implantation of (125)I-labe

Osteoblasts derived from rat bone marrow cells were cultured on surface-modified poly(ethylene terephthalate) films in the presence of ascorbic acid, beta-glycerophosphate, and dexamethasone. The surfaces employed for cell culture included the untreated hydrophobic surface and three modified surfaces possessing immobilized phosphate polymer chains, collagen molecules, and a thin hydroxyapatite-deposited layer. They all were produced by photo-induced graft polymerization with subsequent surface m