Viitasalo A, Pihlajamaki J, Lindi V, Atalay M, Kaminska D, Joro R, Lakka T A
Department of Physiology, Institute of Biomedicine, University of Eastern Finland, Kuopio Campus, Kuopio, Finland; Institute of Dentistry, University of Eastern Finland, Kuopio Campus, Kuopio, Finland.
Pediatr Obes. 2015 Apr;10(2):84-90. doi: 10.1111/ijpo.234. Epub 2014 Jun 11.
PNPLA3 I148M polymorphism (rs738409) has been strongly associated with liver fat content and plasma alanine aminotransferase (ALT) levels in obese adults and children, but little is known about these relationships in normal weight individuals. We studied the associations and interactions of overweight and the PNPLA3 I148M polymorphism with plasma ALT levels during 2-year follow-up in children.
Subjects were a population sample of 481 Caucasian children aged 6-8 years examined at baseline and 419 children re-examined after 2-year follow-up. Altogether, 58 (12%) of 481 children at baseline and 71 (17%) of 419 children after 2-year follow-up were overweight. We assessed plasma ALT levels and other cardiometabolic risk factors and genotyped the PNPLA3 I148M polymorphism.
Being overweight and carrying PNPLA3 148M allele were associated with increased ALT levels at baseline (P = 0.002; P = 0.033) and after 2-year follow-up (P < 0.001; P = 0.001). Being overweight (P < 0.001) and carrying PNPLA3 148M allele (P = 0.001) were also associated with increase in ALT levels during 2-year follow-up. PNPLA3 148M allele carriers had increased ALT levels at baseline (P = 0.024 for interaction) and after 2-year follow-up (P = 0.002 for interaction) as well as a larger increase in ALT levels during 2-year follow-up (P = 0.002 for interaction) if they were overweight but not if they were normal weight. Further adjustment for clinical puberty, dietary factors, physical activity or sedentary behaviour had little or no effect on these associations.
PNPLA3 148M allele carriers had higher plasma ALT levels and larger increase in ALT levels during follow-up than non-carriers only among overweight children.
PNPLA3 I148M多态性（rs738409）与肥胖成人及儿童的肝脏脂肪含量和血浆丙氨酸氨基转移酶（ALT）水平密切相关，但对于正常体重个体的这些关系知之甚少。我们研究了超重及PNPLA3 I148M多态性与儿童2年随访期间血浆ALT水平的关联及相互作用。
研究对象为481名6 - 8岁白种儿童的群体样本，在基线时进行检查，419名儿童在2年随访后再次接受检查。基线时481名儿童中有58名（12%）超重，2年随访后419名儿童中有71名（17%）超重。我们评估了血浆ALT水平及其他心血管代谢危险因素，并对PNPLA3 I148M多态性进行基因分型。
超重及携带PNPLA3 148M等位基因与基线时（P = 0.002；P = 0.033）及2年随访后（P < 0.001；P = 0.001）ALT水平升高相关。超重（P < 0.001）及携带PNPLA3 148M等位基因（P = 0.001）也与2年随访期间ALT水平升高相关。PNPLA3 148M等位基因携带者在基线时（交互作用P = 0.024）及2年随访后（交互作用P = 0.002）ALT水平升高，且在2年随访期间ALT水平升高幅度更大（交互作用P = 0.002），前提是他们超重，若体重正常则不然。进一步对临床青春期、饮食因素、身体活动或久坐行为进行调整，对这些关联影响很小或没有影响。
仅在超重儿童中，PNPLA3 148M等位基因携带者随访期间的血浆ALT水平高于非携带者，且ALT水平升高幅度更大。
