Screening Of Effective Ingredients Of Triterpenoid Saponins From Stauntonia Chinensis And Their Analgesic Effect

Pain is an unpleasant sensory and emotional experience.It not only causes patients to suffer mental and physical pain,but it affects their daily life and work.At present,the mainstay analgesics for pain such as aspirin and opioid,have serious unwanted effects.There is a dire demand for novel analgesic durgs in the clinic.Starntonia Chinensis DC is a traditional Chinese medicine that have effects on anti-inflammation and analgesia.Accumulating studies have found that Triterpenoid Saponins from Stauntonia Chinensis(TSS)can improve the pain threshold of mice caused by thermal stimulation,acetic acid,capsaicin and formalin.In the central nervous system,TSS can enhanced the spontaneous inhibitosy synaptic response in cultured mouse cortical neurons.However,TSS is a mixture whose analgesic effect may be the synergistic effect of some monomers,or the effect of one of the monomers.Taken together,screening the active ingredients of TSS is of great significance for developing novel analgesics.This study aims to screen the active ingredients of TSS and to explore their analgesic mechanisms.First,we used patch clamp technique to record minute inhibitory post synaptic currents(mini-IPSCs).These results showed that the mixture of eight monomers can increase mini-IPSCs.Next,we found that YF-50 is one of the active ingredients of TSS by using method of reverse screening.Further to explore the mechanism of YF-50 in the central nervous system,the mini-IPSCs,minute excitatory post synaptic currents(mini-EPSCs),and evoked-inhibitory post synaptic currents(evoked-IPSCs)of neurons were recorded after incubation with YF-50.We found that the analgesic mechanism of YF-50 is similar to TSS.We also clarified the analgesia effective time of YF-50 and it could last at least 4 hours.Finally,the behaviors experiment suggested that YF-50 can increase the pain threshold caused by thermal stimulation、formalin and acetic acid.This study screened out one of the active ingredients of TSS analgesia——YF-50.We found that the analgesic mechanisms of YF-50 in the CNS is similar to TSS.Simultaneously,the analgesic effect of YF-50 can last for at least 4 hours.Through behavior test,it was found that YF-50 can relieve acute pain.It is further confirmed that YF-50 is one of the effective ingredients of TSS analgesia.