Division of Endocrinology, University of Mississippi School of Medicine, Jackson, MS, USA.
Hormones (Athens). 2012 Apr-Jun;11(2):166-77. doi: 10.14310/horm.2002.1344.
Polymorphisms (SNP) in the glucocorticoid receptor (GR) gene can alter sensitivity to glucocorticoids. Previous studies of the N363S and BclI SNP in the GR gene have shown a metabolic syndrome phenotype in mostly non-African populations. The obesity phenotype of African Americans (AA) seems to be more severe than that of Caucasians.
We aimed to assess the prevalence of N363S and BclI in obese and non-obese Caucasian (n=26) and African (n=23) Mississippians (age: 23-63 years) to investigate associations with body composition (body mass index/BMI, waist-to-hip ratio), metabolic parameters (salivary cortisol, fasting glucose and insulin, hemoglobin A1C, fructosamine, HOMA-IR index), and psychological stress perception (blood pressure/BP, perceived stress scale/PSS).
All subjects were homozygous for wildtype N363N. BclI polymorphism genotype frequencies among the 23 AA were: homozygous CC (57%), GG (4%), and heterozygous CG (39%), and among the 26 white women: homozygous CC (35%), GG (19%), and heterozygous CG (46%). Linear and logistic regression analyses including a parsimonious model identified BMI as a statistically significant parameter between the two ethnic groups (BMI was 3.13 kg/m2 higher in AA). Within the AA group, BMI, waist-to-hip ratio, log (HOMA-IR), PSS scores, BP, and hyperlipidemia showed no statistically significant relationships for the BclI polymorphism. PSS scores were 15.2 for AA vs. 14.7 for white women (normal mean: 14.7 vs. 12.8).
Black Mississippians have a higher BMI than whites, which may be related to the presence of the BclI polymorphism and increased glucocorticoid sensitivity. Although more blacks (52%) than whites (38%) had elevated BP, PSS scores in both groups suggest that a high BMI is not regarded as abnormal or stressful. This might negatively impact behavior change regarding lifestyle modifications with increased physical activity and healthier food choices. Larger studies, particularly in African populations, are needed to better define metabolic and psychological characteristics in relation to the N363S and BclI GR gene polymorphisms.
糖皮质激素受体（GR）基因中的多态性（SNP）可改变对糖皮质激素的敏感性。先前对 GR 基因中的 N363S 和 BclI SNP 的研究表明，非非洲人群中存在代谢综合征表型。非裔美国人（AA）的肥胖表型似乎比白种人更为严重。
我们旨在评估肥胖和非肥胖的密西西比州白种人（n=26）和非洲裔美国人（n=23）中 N363S 和 BclI 的发生率，以研究其与身体成分（体重指数/ BMI、腰臀比）、代谢参数（唾液皮质醇、空腹血糖和胰岛素、糖化血红蛋白、果糖胺、HOMA-IR 指数）和心理应激感知（血压/ BP、感知压力量表/ PSS）的关系。
所有受试者均为 N363N 纯合子。23 名 AA 的 BclI 多态性基因型频率为：纯合 CC（57%）、GG（4%）和杂合 CG（39%），26 名白人女性为：纯合 CC（35%）、GG（19%）和杂合 CG（46%）。线性和逻辑回归分析包括一个简约模型，确定 BMI 是两个种族之间的统计学显著参数（AA 的 BMI 高 3.13kg/m2）。在 AA 组中，BMI、腰臀比、log（HOMA-IR）、PSS 评分、BP 和血脂异常与 BclI 多态性无统计学显著关系。AA 的 PSS 评分为 15.2，白人女性为 14.7（正常均值：14.7 对 12.8）。
密西西比州的黑人 BMI 高于白人，这可能与 BclI 多态性和糖皮质激素敏感性增加有关。尽管黑人（52%）的 BP 升高高于白人（38%），但两组的 PSS 评分表明，高 BMI 并不被视为异常或有压力。这可能会对增加身体活动和更健康的食物选择的生活方式改变行为产生负面影响。需要更大规模的研究，特别是在非洲人群中，以更好地定义与 N363S 和 BclI GR 基因多态性相关的代谢和心理特征。
