Purpose: Probiotic Lactobacillus gasseri SBT2055 (LG2055) has an anti-obesity effect although it is unknown whether the effect influences inflammatory responses in adipose tissue and lipid metabolism in the liver, which are considered substantially relevant to adiposity.
Methods: C57BL/6 mice were fed a 10%-fat diet containing LG2055 cells for 24 weeks. We then studied body weight, fat tissue mass, liver fat content and inflammatory genes in the adipose tissue, and lipogenic and lipolytic genes in the liver.
Results: Consumption of LG2055 resulted in a significant reduction in body weight and fat tissue mass (epididymal and perirenal/retroperitoneal), with a lowered level of triglyceride content in the liver. DNA microarray analysis showed that LG2055 generally inhibited the up-regulation of pro-inflammatory genes, including CCL2 and CCR2, in the epididymal adipose tissue. In the liver, LG2055 tended to inhibit lipogenic gene up-regulation, including ACC1, FAS and SREBP1, but LG2055 did not markedly alter lipolytic genes. Real-time PCR analysis confirmed the DNA microarray results in part, showing a significant reduction in the mRNA expression of CCL2 in the epididymal adipose tissue, and a downward tendency in FAS mRNA expression in the liver, in the LG2055-fed group.
Conclusions: LG2055 significantly prevented body weight gain, fat accumulation and pro-inflammatory gene expression in the adipose tissue. Relatively lower triglyceride levels and reduced expression of lipogenic genes were also observed in the liver. It is suggested that improvement in the inflammatory state of the adipose tissue might be a possible mechanism underlying the anti-obesity effect of LG2055.