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We previously reported the therapeutic potential of human peripheral blood (hPB) CD34+ cells for bone fracture healing via vasculogenesis/angiogenesis and osteogenesis. Transplantation of not only hPB CD34+ cells but also hPB total mononuclear cells (MNCs) has shown their therapeutic efficiency for enhancing ischemic neovascularization. Compared with transplantation of purified hPB CD34+ cells, transplantation of hPB MNCs is more attractive due to its simple method of cell isolation and inexpensive cost performance in the clinical setting. Thus, in this report, we attempted to test a hypothesis that granulocyte colony-stimulating factor-mobilized (GM) hPB MNC transplantation could also contribute to fracture healing via vasculogenesis/angiogenesis and osteogenesis. Nude rats with unhealing fractures received local administration of the following materials with atelocollagen: 1 × 107 GM hPB MNCs (Hi group), 1 × 106 GM hPB MNCs (Lo group), or PBS (PBS group). Immunohistochemistry and real-time reverse transcriptase-polymerase chain reaction (RT-PCR) demonstrated human cell-derived vasculogenesis and osteogenesis in the Hi and Lo groups, but not in the PBS group at week 1. Intrinsic angiogenesis and osteogenesis assessed by rat capillary, osteoblast density, and real-time RT-PCR analysis was significantly enhanced in the Hi group compared to the other groups. Blood flow assessment by laser doppler perfusion imaging showed a significantly higher blood flow ratio at week 1 in the Hi group compared with the other groups. Morphological fracture healing was radiographically and histologically confirmed in about 30% of animals in the Hi group at week 8, whereas all animals in the other groups resulted in nonunion. Local transplantation of GM hPB MNCs contributes to fracture healing via vasculogenesis/angiogenesis and osteogenesis.

Summary Background Skin pigmentation by ultraviolet (UV) B radiation is caused in part by inflammation mediated by chemokines and cytokines secreted by keratinocytes in the irradiated area. However, such inflammatory processes have not been well documented. Objectives To elucidate the inflammation processes caused by UVB irradiation using skin-lightening agents that suppress melanin synthesis after UVB irradiation. Methods Utilizing a three-dimensional (3D) skin model, agents that suppressed formation of sunburn cells (SBC) after UVB irradiation were screened. Molecules whose expression was upregulated by UVB irradiation and attenuated by pretreatment with the agent were then screened by gene microarray to explore the mechanism of UVB irradiation. Messenger RNA expression of the molecules identified to be responsible for melanin biosynthesis was knocked down with a Tet-off shRNA lentivirus construct to confirm the involvement of the molecule in the pigmentation pathway following UVB irradiation. Results Paeonia suffruticosa Andrews (PSA) pretreatment suppressed SBC formation in the 3D skin model, and erythema formation and pigmentation in volunteers exposed to UVB irradiation. Comprehensive gene analysis after UVB irradiation showed upregulation of CXCR3 and its ligands, CXCL9/monokine induced by interferon (IFN)-γ (MIG), CXCL10/10-kDa IFN-γ-induced protein (IP-10) and CXCL11/inducible T-cell α-chemoattractant (I-TAC). Upregulation of these genes was partially suppressed by PSA pretreatment. Melanin biosynthesis increased upon stimulation of CXCR3 ligands (MIG, IP-10 or I-TAC) and decreased following CXCR3 downregulation by shRNA knockdown. Conclusions UVB irradiation activates CXCR3-mediated signalling that leads to melanin synthesis. PSA pretreatment shows a lightening effect partly by attenuating CXCR3-mediated signalling at the transcriptional level.

Impaired fasting glucose (IFG) represents risk of development of diabetes (DM) and its complications. We investigated insulin secretion and insulin sensitivity in 403 IFG subjects divided into three levels of 2-hour postchallenge glucose (2-h PG) to clarify the factors responsible in the development of glucose intolerance in Japanese IFG. Nearly 60% of the subjects at annual medical check-up with FPG of 6.1-7.0 mmol/l at the first screening were diagnosed by 75 g oral glucose tolerance test (OGTT) to have impaired glucose tolerance (IGT; FPG