Asunto(s)
Infecciones por Coronavirus , Pandemias , Neumonía Viral , Síndrome Respiratorio Agudo Grave , Ácido Ascórbico , Betacoronavirus , COVID-19 , Citocinas , Humanos , SARS-CoV-2RESUMEN
In this study, we demonstrated that Withania somnifera L. extract (WSE) protects mice from a lethal dose of Listeria monocytogenes when administered prophylactically at 100, 250 and 500 mg/kg for 10 days, with survival rates up to 30%. These doses also prevented the myelosuppression and the splenomegaly caused by a sublethal infection with L. monocytogenes, due to increased numbers of granulocyte-macrophage progenitors (CFU-GM) in the bone marrow. Investigation of the production of colony-stimulating factors (CSFs) revealed increased colony-stimulating activity (CSA) in the serum of normal and infected mice pre-treated with WSE. Further studies to investigate the levels of interferon-gamma (INF-gamma) and lymphocyte cell proliferation were undertaken. We observed dose-dependent increases in cell proliferation and in the levels of INF-gamma in mice infected with L. monocytogenes and treated with WSE. All together, our results suggest that WSE indirectly modulates immune activity and probably disengages Listeria-induced suppression of these responses by inducing a higher reserve of myeloid progenitors in the bone marrow, proliferation of lymphocytes and increased INF-gamma levels.
Asunto(s)
Listeria monocytogenes , Listeriosis/prevención & control , Withania/química , Animales , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Interferón gamma/inmunología , Listeria monocytogenes/crecimiento & desarrollo , Listeriosis/inmunología , Listeriosis/microbiología , Listeriosis/patología , Linfocitos/citología , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Bazo/citología , Bazo/efectos de los fármacos , Bazo/inmunologíaRESUMEN
In this study, the autonomous proliferation of bone marrow progenitor cells (CFU-C), a pathological phenomenon observed in many hematological abnormalities, was investigated in 31 individuals who had been diagnosed as having neutropenia. Of these subjects, 18 had been chronically exposed (range of exposure 5-30 years) to a variety of petroleum distillates. We observed that the group of exposed individuals presented higher numbers of autonomous CFU-C when compared with those unexposed subjects. In addition, follow-up data demonstrated that 20% of the exposed population (4 of the 18) developed malignant hematological diseases. The autonomous CFU-C obtained from all individuals studied was composed predominantly of macrophages. This suggests an involvement of these cells in the development of hematological abnormalities, probably as a result of increased production of chemical myelotoxic metabolites.