Transcriptomic analyses reveal antiinflammatory mechanism of withanolides derived from the fruits of Physalis alkekengi L. var. franchetii

In China, the fruits of Physalis alkekengi L. var. franchetii, which are conventionally utilized as edible berry, have attracted wide attention due to its significant biological activities. In the present study, phytochemical studies on the fruits of Physalis plants afforded six compounds, including two new withanolides (1-2) and four known agnologues (3-6). The inhibitory effects of these compounds on the formation of nitric oxide (NO) stimulated by lipopolysaccharide (LPS) in RAW264.7 macrophages were evaluated. Physapubescin M (1), with IC50 value of 1.58 mu M, was selected for further study. The protein expression of COX-2 and iNOS, and LPS-induced production of cytokines (IL-6, IL-1 beta and TNF-alpha) were reduced by physapubescin M (1) in a dose-dependent way. In addition, transcriptomic analyses were conducted to profile gene expression alterations in LPS-induced RAW264.7 cells upon treatment of physapubescin M (1) and the potential antiinflammatory mechanism of withnolides was mentioned. These results provide broad view to the underlying antiinflammatory mechanism of withnolides, and give a theoretical basis for the utilization of the fruits of P. alkekengi L. var. franchetii.