RESUMO
Purpurin is a common component ofRubia cordifolia L. The study on its molecular target was useful for elucidating the therapeutic material basis and action mechanism ofR. cordifolia. HT-29 cells were used in the cell culture. The highly expressed G Protein-coupled Receptor-35 (GPR35) agonist was used as target. The label-free optical biosensor cellular assay was used to investigate the agonist activity ofpurpurin at an endogenous receptor. The results showed thatpurpurin can cause DMR response in HT-29 cells. And the DMR response curve type was consistent with zaprinast. Its EC50 was 6.142± 0.189μmol·L-1. In addition,purpurinhad desensitization effect on GPR35 agonist zaprinast in HT-29 cells. GPR35 agonist ML145 blocked the DMR ofpurpurin. It was concluded thatpurpurinwas the GPR35 agonist.
RESUMO
AIM@#To determine the IPP origin of the naphthoquinones (NQs) in Rubia cordifolia, and to evaluate the effects of methyl jasmonate (MeJA) treatment, MEP, and MVA pathway inhibitor treatment on the accumulation of anthraquinones (AQs) and NQs in cell suspension cultures of R. cordifolia.@*METHODS@#Cell suspension cultures of R. cordifolia were established. Specific inhibitors (lovastatin and clomazone) and MeJA were supplied to the media, respectively. Treated cells were sampled every three days. Content determination of purpurin (AQs) and mollugin (NQs) were carried out using RP-HPLC. The yield of the two compounds was compared with the DMSO-supplied group and the possible mechanism was discussed.@*RESULTS@#Lovastatin treatment increased the yield of purpurin and mollugin significantly. Clomazone treatment resulted in a remarkable decrease of both compounds. In the MeJA-treated cells, the purpurin yield increased, meanwhile, the mollugin yield decreased compared with control.@*CONCLUSION@#The IPP origin of mollugin in R. cordifolia cell suspension cultures was likely from the MEP pathway. To explain the different effects of MeJA on AQs and NQs accumulation, studies on the regulation and expression of the genes, especially after prenylation of 1,4-dihydroxy-2-naphthoic acid should be conducted.