RESUMO
Four (1-4) hitherto unknown and seven (5-11) known ergostane-type sterols were isolated from the EtOH extract of the dried fruiting bodies of the polypore macrofungus Fomes fomentarius. On the basis of spectroscopic analysis, the structures of polyhydroxylated sterols 1-4 were elucidated to be (22E,24R)-3ß,5α,6ß,14α-tetrahydroxyergosta-7,9(11),22-triene (fomentarol A, 1), (22E,24R)-3ß,5ß,6α,7α-tetrahydroxy-8α,9α-dihydroergosta-14,22-diene (fomentarol B, 2), (22E,24R)-3ß,5α-dihydroxy-6ß-ethoxyergosta-7,22-diene (fomentarol C, 3), and (22E,24S)-3ß,25-dihydroxy-15α-O-ß-D-glucopyranosylergosta-7,22-dien-6-one (fomentarol D, 4), respectively. Rings A/B and B/C are in turn cis-fused in compound 2, which is uncommon in natural ergostane-type sterols. The potential biogenetic relationship of 2 and other ergostane-type sterols isolated from F. fomentarius was briefly discussed. Moderate cytotoxic effects of the isolated sterols against a small panel of human cancer cell lines were also established.
Assuntos
Coriolaceae/química , Esteróis/isolamento & purificação , Conformação Molecular , Estereoisomerismo , Esteróis/químicaRESUMO
Although corticosteroid-induced osteonecrosis of the femoral head (ONFH) is common, the treatment for it remains limited and largely ineffective. We examined whether implantation of hypoxia inducible factor-1α (HIF-1α) transgenic bone marrow cells (BMCs) can promote the repair of the necrotic area of corticosteroid-induced ONFH. In this study, we confirmed that HIF-1α gene transfection could enhance mRNA expression of osteogenic genes in BMCs in vitro. Alkaline phosphatase activity assay and alizarin red-S staining indicated HIF-1α transgenic BMCs had enhanced osteogenic differentiation capacity in vitro. Furthermore, enzyme linked immunosorbent assay (ELISA) for VEGF revealed HIF-1α transgenic BMCs secreted more VEGF as compared to normal BMCs. An experimental rabbit model of early-stage corticosteroid-induced ONFH was established and used for an evaluation of cytotherapy. Transplantation of HIF-1α transgenic BMCs dramatically improved the bone regeneration of the necrotic area of the femoral head. The number and volume of blood vessel were significantly increased in the necrotic area of the femoral head compared to the control groups. These results support HIF-1α transgenic BMCs have enhanced osteogenic and angiogenic activity in vitro and in vivo. Transplantation of HIF-1α transgenic BMCs can potentially promote the repair of the necrotic area of corticosteroid-induced ONFH.
Assuntos
Células da Medula Óssea/metabolismo , Regeneração Óssea , Necrose da Cabeça do Fêmur/terapia , Cabeça do Fêmur/irrigação sanguínea , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Osteogênese , Corticosteroides , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Células da Medula Óssea/citologia , Transplante de Medula Óssea , Diferenciação Celular , Engenharia Celular , Células Cultivadas , Cabeça do Fêmur/metabolismo , Cabeça do Fêmur/patologia , Necrose da Cabeça do Fêmur/induzido quimicamente , Necrose da Cabeça do Fêmur/metabolismo , Necrose da Cabeça do Fêmur/patologia , Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Neovascularização Fisiológica , Coelhos , Transgenes , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Ten new triterpenoids, named meliasenins I-R (1-10), one new steroid (11), and 11 related known compounds (12-22) were isolated from fruits of Melia toosendan. The structures of the new compounds were established on the basis of spectroscopic methods, including 2D NMR techniques and mass spectrometry. The relative configuration of 1, (20R*,23E)-25-hydroperoxyeupha-7,23-diene-3ß,16ß-diol (meliasenin I), was confirmed by single-crystal X-ray diffraction analysis. All isolated triterpenoids (1-10, 12-15) and two steroids (11, 20) were tested for their cytotoxicity against U20S human osteosarcoma and MCF-7 human breast cancer cells using the MTT assay, and some of them were significantly cytotoxic (IC(50) <10 µg/mL). The insecticidal properties of compounds 1-15 and 20 were also briefly evaluated.