Analgesic Effects of Triterpenoid Saponins From Stauntonia chinensis via Selective Increase in Inhibitory Synaptic Response in Mouse Cortical Neurons

Abstract

Triterpenoid saponins from Stauntonia chinensis (TSS) are potential therapeutic agents because of its analgesic properties. However, the underlying mechanisms of the anti-nociceptive activity of TSS are largely unclear, especially in CNS. The present study confirmed the analgesic effect of TSS using four models of acute pain based on thermal or chemical stimuli. TSS treatment specifically impaired the threshold of thermal- and chemical-stimulated acute pain. Naloxone did not block the anti-nociceptive effects of TSS, which showed no participation of the opioid system. We investigated the electrical signal in cultured cortical neurons to explore whether TSS treatment directly affected synaptic transmission. TSS treatment selectively increased spontaneous inhibitory synaptic release and GABA induced charge transfer in mouse cortical neurons. The effects of TSS were maintained for at least 8 h in cultured neurons and in injected mice. Taken together, our results suggest that the analgesic role of TSS in cortex occurs via a particular increase in the inhibitory synaptic response at resting state, which supports TSS as a potential candidate for inflammatory pain relief.

Identification and quantification of oleanane triterpenoid saponins and potential analgesic and anti-inflammatory activities from the roots and rhizomes of Panax stipuleanatus

“…For example, total saponins of Psammosilene tunicoids inhibited algesia threshold and effectively decreased the contents of MDA, IL-1β, and TNF-α in the inflammatory tissue soak of rats with adjuvant-induced arthritis [ 17 , 18 ]. The triterpenoid saponins from Stauntonia chinensis enhanced the threshold of thermal- and chemical-stimulated acute pain, which directly increased the inhibitory synaptic response in mouse cortex neurons at the resting state [ 19 ]. P. stipuleanatus was traditionally used to treat pain-related diseases.…”

The Hydroethanolic Stem Bark Extract of Tieghemella heckelii (A.Chev.) Pierre ex Dubard (Sapotaceae) Produced N-Methyl-D-Aspartate (NMDA) Receptor-Dependent Analgesia and Attenuates Acute Inflammatory Pain via Disruption of Oxidative Stress

“…Other reports indicated that quercetin produce anti-inflammatory action in mouse models of colitis, periodontitis, cancer pain, and acute pain via exertion of the inhibitory effect on neutrophil recruitments, oxidative stress, and COX-2 [ 42 – 44 ]. Also, saponin containing plant such as Stauntonia chinensis has been reported to demonstrate significant analgesia in the mouse hot plate, acetic acid-induced writhing, formalin, and capsaicin tests through elevation of the inhibitory synaptic response in cortical neurons [ 45 ]. Therefore, the presence of flavonoids, phenolic compounds, and saponins in THBE may contribute to its profound attenuation of acute nociceptive and inflammatory pain in this study.…”

Phytochemical, Antioxidant and Anti-Inflammatory Characterization of Leaves and Bark of Mimusops coriacea (A.DC) Miq from Ecuador

“…44,45 Triterpenic saponins also exhibit antioxidant and anti-inflammatory properties. 46,47 A greater antioxidant and anti-inflammatory activity were observed for the leaf extract, which presented the highest concentration of phenols and flavonoids. It has been shown that these metabolites can contribute directly to the activities previously described.…”