Bhattacharyya A K, Connor W E
J Clin Invest. 1974 Apr;53(4):1033-43. doi: 10.1172/JCI107640.
Although the usual diet may contain 150-250 mg of plant sterols, chiefly beta-sitosterol, only trace amounts of these sterols have heretofore been found in human or animal blood and tissues. We now report elevated plant sterol levels in the blood and tissues of two sisters with extensive tendon xanthomas but normal plasma cholesterol levels. Besides beta-sitosterolemia and xanthomatosis, no other physical, mental, or biochemical abnormalities were detected.Repeatedly, the plasmas of the two sisters have contained 27.1 and 17.7 mg/100 ml of beta-sitosterol, 9.7 and 8.2 mg/100 ml of campesterol, and 0.5 and 0.5 mg/100 ml of stigmasterol, respectively. These plant sterols constituted 15.6 and 11.3% of the total plasma sterols. Some 60% of the plasma beta-sitosterol and campesterol was esterified; the measurable stigmasterol was entirely unesterified. The transport of the plasma beta-sitosterol and campesterol was largely in low density lipoproteins (76 and 83%, respectively). High density lipoproteins carried the remainder. Plant sterols were barely detectable in the very low density lipoprotein fraction. Only trace amounts of stigmasterol could be detected in the low density and high density lipoprotein fractions. The plant sterol content of the red blood cells averaged 12-13 mg/100 ml packed cells or about 13% of the total sterols. Two tendon xanthoma biopsies with the usual high concentration of cholesterol had 36.7 and 4.0 mg of plant sterols/g dry wt, of which 25.7 and 2.9 mg were beta-sitosterol, entirely in the free form. Plant sterols were also found in adipose tissue (0.2 mg/g wet wt) and in skin surface lipids (3.2 mg/g of lipid). The intestinal absorption of beta-sitosterol in both the patients, measured by two techniques, indicated greatly increased absorption of this sterol (about 24 and 28% in the patients L. H. and R. H., respectively, normal absorption being <5%). We suggest that increased absorption of beta-sitosterol must be considered as one cause of this disease. The reason for the extensive xanthomatosis in these two patients remains unknown. Perhaps in some way plant sterols initiated the development of xanthomas with otherwise normal plasma cholesterol levels. Clinical atherosclerosis has not yet occurred. The occurrence of beta-sitosterolemia in these two sisters with un-affected parents suggests an inherited recessive trait.
尽管日常饮食中可能含有150 - 250毫克的植物甾醇，主要是β - 谷甾醇，但迄今为止，在人类或动物的血液和组织中仅发现极少量的这些甾醇。我们现在报告两名患有广泛肌腱黄色瘤但血浆胆固醇水平正常的姐妹，其血液和组织中的植物甾醇水平升高。除了β - 谷甾醇血症和黄色瘤病外，未检测到其他身体、精神或生化异常。这两名姐妹的血浆中，β - 谷甾醇含量分别为27.1和17.7毫克/100毫升，菜油甾醇含量分别为9.7和8.2毫克/100毫升，豆甾醇含量分别为0.5和0.5毫克/100毫升。这些植物甾醇分别占血浆总甾醇的15.6%和11.3%。血浆中约60%的β - 谷甾醇和菜油甾醇被酯化；可测量的豆甾醇则完全未被酯化。血浆中β - 谷甾醇和菜油甾醇的转运主要存在于低密度脂蛋白中（分别为76%和83%）。高密度脂蛋白携带其余部分。极低密度脂蛋白部分几乎检测不到植物甾醇。在低密度和高密度脂蛋白部分仅能检测到极少量的豆甾醇。红细胞中的植物甾醇含量平均为12 - 13毫克/100毫升压实细胞，约占总甾醇的13%。两份肌腱黄色瘤活检标本中胆固醇含量通常较高，植物甾醇含量分别为36.7和4.0毫克/克干重，其中25.7和2.9毫克为β - 谷甾醇，均为游离形式。在脂肪组织（0.2毫克/克湿重）和皮肤表面脂质（3.2毫克/克脂质）中也发现了植物甾醇。通过两种技术测量，两名患者中β - 谷甾醇的肠道吸收表明该甾醇的吸收大幅增加（患者L.H.和R.H.分别约为24%和28%，正常吸收<5%）。我们认为β - 谷甾醇吸收增加必须被视为这种疾病的一个原因。这两名患者广泛发生黄色瘤病的原因尚不清楚。也许植物甾醇以某种方式引发了血浆胆固醇水平正常的患者黄色瘤的发展。临床动脉粥样硬化尚未发生。这两名姐妹患有β - 谷甾醇血症，而其父母未受影响，提示这是一种隐性遗传特征。
