Just wanted to reiterate and point this out,
Berberine alters the expression of metabolic genes in fat and muscle in vivo.
To investigate the mechanism of berberine action on insulin action and body weight, we next assessed the effects of berberine on the expression of certain genes that are known to play a critical role in energy balance. As shown in Fig. 4A, the expression of a number of adipocyte-specific genes including fatty acid synthase (FAS), ADD1/SREBP1c (adipocyte determination and differentiation-dependent factor 1/sterol regulatory element-binding protein 1c), peroxisome proliferator-activated receptor (PPAR)?, 11?-hydroxysteroid dehydrogenase 1 (11?-HSD1), and aP2 was reduced in various WAT depots of berberine-treated mice. In contrast, the level of cyclin D kinase 5 mRNA was not significantly altered, indicating that the inhibitory effect of berberine on gene expression was restricted to adipogenic and lipogenic genes. Conversely, in skeletal muscle, the expression of uncoupling protein (UCP) 2 mRNA was significantly increased by berberine, while that of UCP3 was unchanged (Fig. 4B). In brown adipose tissue, the expression of PPAR? mRNA also increased dramatically, while the mRNA of lipogenic genes such as FAS was reduced as in the case of WAT (Fig. 4C). Additionally, expression of PPAR? coactivator-1, a key regulator of several mitochondrial genes involved in adaptive thermogenesis, was substantially increased (Fig. 4C).
To further investigate the effects of berberine on overall gene expression, we compared genome-wide expression profiles in the WAT of berberine-treated mice and control mice using DNA microarrays. The genes that responded reproducibly to berberine were categorized by their fold induction (>1.5-fold, 996 genes) or repression (<0.8-fold, 1,483 genes) (online appendix Table 1 [available at
http://diabetes.diabetesjournals.org]). Most genes involved in lipogenesis were downregulated by berberine treatment; for example, FAS and fatty acid desaturase 3, which control the final step of triglyceride synthesis from malonyl-CoA to palmitate and from phosphatidic acid to triglycerides, respectively, decreased 0.59- and 0.27-fold, respectively. Interestingly, 11?-HSD1, a key enzyme linked to visceral obesity and metabolic syndrome, decreased 0.63-fold, and expression of most genes involved in carbohydrate metabolism was also reduced (online appendix Table 1). In contrast, the transcript level of enzymes related to energy dissipation, including glycerol kinase and acyl-CoA dehydrogenase, increased 4.0- and 2.2-fold, respectively. These results imply that berberine treatment in vivo results in an altered gene expression profile that would promote catabolism of high energy intermediates (online appendix Fig. 1).
http://diabetesdiabetesjournals.needdiets.com/content/55/8/2256.full