Muldoon M F, Kritchevsky S B, Evans R W, Kagan V E
Center for Clinical Pharmacology, University of Pittsburg School of Medicine, PA 15260, USA. mfm10+@pitt.edu
Free Radic Res. 1996 Sep;25(3):239-45. doi: 10.3109/10715769609149049.
Individuals with low serum cholesterol experience greater than expected age-adjusted mortality from non-atherosclerotic diseases, including cancer, respiratory and digestive illnesses, but the basis for these associations remains unclear. The current investigation considered the hypothesis that hypocholesterolemia is associated with reduced antioxidant reserve. Serum total antioxidant activity as well as concentrations of vitamin E, vitamin C, and thiols were compared in two groups of 24 subjects distinct in both mean low density lipoprotein (LDL) cholesterol (2.3 v. 4.9 mM) and mean total cholesterol (4.3 v. 7.0 mM). The low and high cholesterol groups were equivalent in gender mix, age, weight, and serum total protein. Results reveal that compared with the high group, the low cholesterol group had decreased total serum antioxidant activity (p < .05). Thiol concentrations were also lower in the low cholesterol group (p < .05). Group differences in serum total antioxidant activity and thiol concentration were larger among men than women. The two groups did not differ in vitamin C. Low cholesterol was associated with reduced absolute vitamin E levels, although the tocopherol: cholesterol ratio was the same in low and high cholesterol individuals. These data indicate that hypocholesterolemia may be associated with low serum antioxidant reserve, possibly increasing susceptibility to oxidative stress.
血清胆固醇水平较低的个体，在年龄调整后，因非动脉粥样硬化性疾病（包括癌症、呼吸道疾病和消化系统疾病）导致的死亡率高于预期，但这些关联的基础仍不清楚。当前的研究考虑了低胆固醇血症与抗氧化储备降低相关的假说。在两组各24名受试者中，比较了血清总抗氧化活性以及维生素E、维生素C和硫醇的浓度。这两组受试者的平均低密度脂蛋白（LDL）胆固醇水平（分别为2.3 mM和4.9 mM）和平均总胆固醇水平（分别为4.3 mM和7.0 mM）存在差异。低胆固醇组和高胆固醇组在性别构成、年龄、体重和血清总蛋白方面相当。结果显示，与高胆固醇组相比，低胆固醇组的血清总抗氧化活性降低（p < 0.05）。低胆固醇组的硫醇浓度也较低（p < 0.05）。血清总抗氧化活性和硫醇浓度的组间差异在男性中比女性更大。两组在维生素C方面没有差异。低胆固醇与维生素E的绝对水平降低有关，尽管低胆固醇个体和高胆固醇个体的生育酚：胆固醇比值相同。这些数据表明，低胆固醇血症可能与血清抗氧化储备降低有关，可能会增加对氧化应激的易感性。
