Glutathione (GSH), a major cellular antioxidant protects cells against oxidative stress injury. Nuclear factor erythroid 2-related factor 2 (NFE2L2/Nrf2) is a redox sensitive master regulator of battery of antioxidant...Glutathione (GSH), a major cellular antioxidant protects cells against oxidative stress injury. Nuclear factor erythroid 2-related factor 2 (NFE2L2/Nrf2) is a redox sensitive master regulator of battery of antioxidant enzymes including those involved in GSH antioxidant machinery. Earlier we reported that ethanol (ETOH) elicits apoptotic death of pri-mary cortical neurons (PCNs) which in partly due to depletion of intracellular GSH levels. Further a recent report from our laboratory illustrated that ETOH exacerbated the dysregulation of GSH and caspase mediated cell death of pure cortical neurons that are compromised in Nrf2 machinery (Narasimhan et al., 2011). In various experimental models of neurodegeneration, neuronal antioxidant defenses mainly GSH has been shown to be supported by astrocytes. We therefore sought to determine whether astrocytes can render protection to neurons against ETOH toxicity, particularly when the function of Nrf2 is compromised in neurons. The experimental model consisted of co-culturing PCAs with Nrf2 downregulated PCNs that were exposed with and without 4 mg/mL ETOH for 24 h. Monochlorobimane (MCB) staining followed by FACS analysis showed that astrocytes blocked ETOH induced GSH decrement in Nrf2-silenced neurons as opposed to exaggerated GSH depletion in Nrf2 downregulated PCNs alone. Similarly, the heightened activa-tion of caspase 3/7 observed in Nrf2-compromised neurons was attenuated when co-cultured with astrocytes as meas-ured by luminescence based caspase Glo assay. Furthermore, annexin-V-FITC staining followed by FACS analysis re-vealed that Nrf2 depleted neurons showed resistance to ETOH induced neuronal apoptosis when co-cultured with as-trocytes. Thus, the current study identifies ETOH induced dysregulation of GSH and associated apoptotic events ob-served in Nrf2-depleted neurons can be blocked by astrocytes. Further our results suggest that this neuroprotective ef-fect of astrocyte despite dysfunctional Nrf2 system in neurons could be compensated by astrocytic GSH supply.展开更多
The micromass culture was used to determine the effects of vanadium pentoxide (V2O5 ) on the proliferation and differentiation of limb bud cells of rat. In the in vitro test, the results showed that V2O5 had obvious i...The micromass culture was used to determine the effects of vanadium pentoxide (V2O5 ) on the proliferation and differentiation of limb bud cells of rat. In the in vitro test, the results showed that V2O5 had obvious inhibiting effects on both proliferation and differentiation of limb bud cells with a dosedependent response, its proliferating and differentiating IC50 being 13.64 and 4.77μmol/L, respectively. In the in vivo/in vitro test, the results showed that V2O5 had no obvious effect on cell proliferation but had obvious inhibiting effect on cell differentiation. These results indicated that V2O5 might have a specific inhibiting effect on the differentiation of limb bud cells.展开更多
为深入揭示同型半胱氨酸(hom ocysteine,HCY)的致畸性及作用机理,应用大鼠胚胎中脑细胞微团培养法探讨了HCY(0～10m m ol/L)对胚胎中脑细胞增殖和分化的影响。结果显示:随着剂量的增加,HCY对胚胎中脑细胞分化具有促进和抑制双相作用,半...为深入揭示同型半胱氨酸(hom ocysteine,HCY)的致畸性及作用机理,应用大鼠胚胎中脑细胞微团培养法探讨了HCY(0～10m m ol/L)对胚胎中脑细胞增殖和分化的影响。结果显示:随着剂量的增加,HCY对胚胎中脑细胞分化具有促进和抑制双相作用,半数抑制分化浓度(IC50 )为4.3m m ol/L,当加入肝微粒体S9时,IC50减至2.3m m ol/L;在实验剂量范围内,HCY对中脑细胞增殖无明显抑制作用。上述结果说明HCY 对大鼠胚胎中脑细胞分化的影响明显高于对细胞增殖的影响。展开更多
文摘Glutathione (GSH), a major cellular antioxidant protects cells against oxidative stress injury. Nuclear factor erythroid 2-related factor 2 (NFE2L2/Nrf2) is a redox sensitive master regulator of battery of antioxidant enzymes including those involved in GSH antioxidant machinery. Earlier we reported that ethanol (ETOH) elicits apoptotic death of pri-mary cortical neurons (PCNs) which in partly due to depletion of intracellular GSH levels. Further a recent report from our laboratory illustrated that ETOH exacerbated the dysregulation of GSH and caspase mediated cell death of pure cortical neurons that are compromised in Nrf2 machinery (Narasimhan et al., 2011). In various experimental models of neurodegeneration, neuronal antioxidant defenses mainly GSH has been shown to be supported by astrocytes. We therefore sought to determine whether astrocytes can render protection to neurons against ETOH toxicity, particularly when the function of Nrf2 is compromised in neurons. The experimental model consisted of co-culturing PCAs with Nrf2 downregulated PCNs that were exposed with and without 4 mg/mL ETOH for 24 h. Monochlorobimane (MCB) staining followed by FACS analysis showed that astrocytes blocked ETOH induced GSH decrement in Nrf2-silenced neurons as opposed to exaggerated GSH depletion in Nrf2 downregulated PCNs alone. Similarly, the heightened activa-tion of caspase 3/7 observed in Nrf2-compromised neurons was attenuated when co-cultured with astrocytes as meas-ured by luminescence based caspase Glo assay. Furthermore, annexin-V-FITC staining followed by FACS analysis re-vealed that Nrf2 depleted neurons showed resistance to ETOH induced neuronal apoptosis when co-cultured with as-trocytes. Thus, the current study identifies ETOH induced dysregulation of GSH and associated apoptotic events ob-served in Nrf2-depleted neurons can be blocked by astrocytes. Further our results suggest that this neuroprotective ef-fect of astrocyte despite dysfunctional Nrf2 system in neurons could be compensated by astrocytic GSH supply.
文摘The micromass culture was used to determine the effects of vanadium pentoxide (V2O5 ) on the proliferation and differentiation of limb bud cells of rat. In the in vitro test, the results showed that V2O5 had obvious inhibiting effects on both proliferation and differentiation of limb bud cells with a dosedependent response, its proliferating and differentiating IC50 being 13.64 and 4.77μmol/L, respectively. In the in vivo/in vitro test, the results showed that V2O5 had no obvious effect on cell proliferation but had obvious inhibiting effect on cell differentiation. These results indicated that V2O5 might have a specific inhibiting effect on the differentiation of limb bud cells.
文摘为深入揭示同型半胱氨酸(hom ocysteine,HCY)的致畸性及作用机理,应用大鼠胚胎中脑细胞微团培养法探讨了HCY(0～10m m ol/L)对胚胎中脑细胞增殖和分化的影响。结果显示:随着剂量的增加,HCY对胚胎中脑细胞分化具有促进和抑制双相作用,半数抑制分化浓度(IC50 )为4.3m m ol/L,当加入肝微粒体S9时,IC50减至2.3m m ol/L;在实验剂量范围内,HCY对中脑细胞增殖无明显抑制作用。上述结果说明HCY 对大鼠胚胎中脑细胞分化的影响明显高于对细胞增殖的影响。
