Gene expression profiling of rat livers with Yin-deficiency-heat syndrome

OBJECTIVE： To explore the nature of ＂Yin internal heat caused by Yin-deficiency＂ in terms of the theo- ry of Traditional Chinese Medicine, by studying en- ergy metabolism in rats with Yin-deficiency-heat syndrome and analyzing the gene expression pro- file of their livers. METHODS： A Yin-deficiency-heat syndrome model was induced in rats using three Chinese medicinal herbs. Glycogen and triglycerides in blood plasma, and the enzyme activity of ATP in livers were mea- sured colorimetrically. Triiodothyronine （T3）, thyrox- ine （T4）, and thyroid stimulating hormone levels in blood plasma were also measured with enzyme linked immunosorbent assay. The gene expression profile of livers was detected with gene chip analy- sis. Differentially expressed genes were screened out and classified according to Gene Ontology. The accuracy of results were examined with reversetranscription-polymerase chain reaction RESULTS： Compared with the control group, body weight （P〈0.05） and hepatic glycogen （P〈0.05） were significantly lower in the Yin-deficiency-heat syndrome group. Moreover, toe temperature （P〈 0.01） and triglyceride （P〈0.05）, Na ＋-K＋-ATPase （P〈 0.01）, Mg2＋-ATPase （P〈0.01）, T3 （P〈0.05）, and 1-4 （P〈 0.01） levels were significantly higher. There were 99 differentially expressed genes in livers from the Y/n-deficiency-heat syndrome group. Genes were mainly related to sterol synthesis （Pc=0.0392）, de- fense response （Pc=0.0448）, and sterol metabolism （Pc=0.0533）. CONCLUSION： Abnormal expression genes in rats with Yin-deficiency-heat syndrome prompted the synthesis and metabolism of cholesterol, increased energy consumption, and reduced defense re- sponse. This gene expression might be the molecu- lar mechanism underlying ＂internal heat caused by Yin-deficiency＂ in the rats with Yin-deficiency-heat syndrome.