[Anti-radiation effect and mechanism studies of ethanol extracts from Spatholobus suberectus and its active component catechin].

To study the anti-radiation effect and mechanism of ethanol extracts from Spatholobus suberectus and its active component catechin, ICR mice were exposed to 6Gy irradiation and randomly divided into normal group, model group, positive control group (amifostine, 43.6 mg•kg⁻¹, iv 30 min before irradiation), SSD group (10, 20, 40 g•kg⁻¹) and catechin group (50, 100, 200 mg•kg⁻¹). The mice were administered the appropriate drugs once a day after irradiation for 28 consecutive days. Blood samples were collected from the tail end and the number of peripheral blood cells was counted before irradiation and on day 1, 3, 7, 14, 21 and 28 using a microcell counter. Changes of thymus and spleen index of mice on day 7 were observed. The serum SOD, GSH-Px activity and MDA level were detected by the colorimetric method. The colony forming ability of bone marrow hematopoietic progenitor cells on day 7 was detected by semi solid culture method. The HE staining was adopted to observe the pathological changes. The apoptosis of bone marrow cells was detected by flow cytometry. The expression of cleaved caspase-3 and Bax of bone marrow cells were measured separately by western-blotting and immunohistochemistry method. SSD and catechin can both significantly revert the irradiated-induced decline in hematological parameters (RBC, WBC, PLT, Hb), improve thymus and spleen index, significantly enhance serum SOD and GSH-Px activity and decrease the MDA level. The proliferation and differentiation of hematopoietic progenitor cells in bone marrow were promoted, the apoptosis of bone marrow cells was significantly up-regulated and the expression of cleaved caspase-3 and Bax was significantly reduced in SSD and catechin group. SSD and catechin have significant anti-radiation effect and its mechanism may be related to hematopoietic promoting, antioxidant and anti-apoptotic effects.

Anti-radiation effect and mechanism studies of ethanol extracts from Spatholobus suberectus and its active component catechin / 中国中药杂志

To study the anti-radiation effect and mechanism of ethanol extracts from Spatholobus suberectus and its active component catechin, ICR mice were exposed to 6Gy irradiation and randomly divided into normal group, model group, positive control group (amifostine, 43.6 mg•kg⁻¹, iv 30 min before irradiation), SSD group (10, 20, 40 g•kg⁻¹) and catechin group (50, 100, 200 mg•kg⁻¹). The mice were administered the appropriate drugs once a day after irradiation for 28 consecutive days. Blood samples were collected from the tail end and the number of peripheral blood cells was counted before irradiation and on day 1, 3, 7, 14, 21 and 28 using a microcell counter. Changes of thymus and spleen index of mice on day 7 were observed. The serum SOD, GSH-Px activity and MDA level were detected by the colorimetric method. The colony forming ability of bone marrow hematopoietic progenitor cells on day 7 was detected by semi solid culture method. The HE staining was adopted to observe the pathological changes. The apoptosis of bone marrow cells was detected by flow cytometry. The expression of cleaved caspase-3 and Bax of bone marrow cells were measured separately by western-blotting and immunohistochemistry method. SSD and catechin can both significantly revert the irradiated-induced decline in hematological parameters (RBC, WBC, PLT, Hb), improve thymus and spleen index, significantly enhance serum SOD and GSH-Px activity and decrease the MDA level. The proliferation and differentiation of hematopoietic progenitor cells in bone marrow were promoted, the apoptosis of bone marrow cells was significantly up-regulated and the expression of cleaved caspase-3 and Bax was significantly reduced in SSD and catechin group. SSD and catechin have significant anti-radiation effect and its mechanism may be related to hematopoietic promoting, antioxidant and anti-apoptotic effects.

Hemopoietic progenitor cell identification in fetal and adult blood / Célula progenitora hamatopoética: identificação em sangue fetal e de adulto

Hemopoietic progenitor cells give rise to all cellular elements of the blood and are of importance as a potential source of cells used for correction of various pathological conditions. The main objective of this study was to identify and quantitative hemopoietic progenitor cell in antenatal fetal blood, in cord blood at the time of delivery and in adult blood, using monoclonal antibodies to surface markers and flow cytometry. CD34+ cells, most of them probably representing progenitor cells, were detected in prenatal fetal blood as early as the 17th week of gestation. The proportion of these cells showed a tendency to decrease as the pregnancy progressed. Within the population of CD34+ cells, a relatively low proportion (less than 1 percent) were negative for the surface marker CD33 or HLA-Dr, indicating a population of primitive stem cells, i.e., progenitor cells no committed to a specific lineage. On the contrary, another group coexpressed CD33 or HLA-Dr, being more mature progenitor cells already committed to differentiate along a specific lineage. The percentage of CD34+ obtained in blood of adult patients after mobilization with chemotherapeutic agents and growth factors showed an average value of 2.7± 3.1 percent. The percentage of CD34+ in the apheresis products of various patients varied from 0.58 to 1.48. In some cases the cells were reinfused in the patient with good results. Our findings are in agreement with previous studies suggesting that CD34+ stem cells is a heterogeneous population, with each subset having variable degree o commitment to differentiate toward a specific cell lineage.

As células progenitoras hematopoéticas são as responsáveis pela produção de todos os elementos do sangue e são as potenciais fontes de células usadas para o tratamento de várias condições patológicas. O principal objetivo deste trabalho foi identificar e quantificar as células progenitoras hematopoiéticas no sangue fetal do período pré-natal, no sangue de cordão umbilical no momento do parto e no sangue do adulto, usando anticorpos monoclonais para marcadores de superfície e citometria de fluxo. As células CD34+ na maioria das vezes representam células progenitoras e foram detectadas no sangue fetal pré-natal tão precoce como na 17ª semana de gestação. A proporção destas células mostrou a tendência de diminuir durante a progressão da gestação. Dentro da população de células CD34+, uma proporção relativamente pequena (menos de 1 por cento) foi negativa para os marcadores de superfície CD33 ou HLA-Dr, indicando uma população de células primitivas, isto é, células progenitoras não comissionadas com uma linhagem específica. Ao contrário, outro grupo co-expressa CD33 ou HLA-Dr, sendo progenitores celulares mais maduros já comprometidos com linhagens específicas. A porcentagem de CD34+ obtida no sangue de adultos após mobilização com agentes quimioterápicos e fator de crescimento mostrou uma média de 2.7+/-3.1 por cento. 0 por cento de CD34+ no produto aferético de vários pacientes variou de 0.58 a 1.48. Em alguns casos as células foram infundidas nos pacientes com bons resultados. Nossos achados estão de acordo com estudos prévios sugerindo que células CD34+ sejam uma população heterogênea com cada subgrupo apresentando graus de comprometimento com diferentes linhagens específicas.