PolyphyllinVI alleviates the spared nerve injury-induced neuropathic pain based on P2X3 receptor-mediated the release of inflammatory mediators.

ETHNOPHARMACOLOGICAL RELEVANCE: PolyphyllinVI (PPⅥ) is the main bioactive component of Chonglou which is a traditional Chinese herbal with various effects, including antitumor, anti-inflammatory, and analgesia. AIM OF THE STUDY: This study aimed to investigate the properties and mechanisms of the analgesia of PPⅥ by using neuropathic pain (NPP) mice. MATERIALS AND METHODS: The potential targets and mechanisms of PPⅥ in alleviating NPP were excavated based on the network pharmacology. Subsequently, the construction of a spared nerve injury (SNI) mice model was used to evaluate the effect of PPⅥ on NPP and the expression of the P2X3 receptor. We identified the signaling pathways of PPⅥ analgesia by RNA sequencing. RESULTS: The results of network pharmacology showed that BCL2, CASP3, JUN, STAT3, and TNF were the key targets of the analgesic effect of PPⅥ. PPⅥ increased the MWT and TWL of SNI mice and decreased the level of P2X3 receptors in the dorsal root ganglion (DRG) and spinal cord (SC). Additionally, PPⅥ reduced the release of pro-inflammatory mediators (TNF-α, IL-1ß, and IL-6) in the DRG, SC, and serum. Based on the KEGG enrichment of differentially expressed genes (DEGs) identified by RNA-Seq, PPVI may relieve NPP by regulating the AMPK/NF-κB signaling pathway. Western blotting results showed that the AMPK signaling pathway was activated, followed by inhibition of the NF-κB signaling pathway. CONCLUSION: PPⅥ increased the MWT and TWL of SNI mice maybe by inhibiting the expression of the P2X3 receptor and the release of inflammatory mediators. The properties of the analgesia of PPⅥ may be based on the AMPK/NF-κB pathway.

Anti-inflammatory and analgesic properties of Polyphyllin VI revealed by network pharmacology and RNA sequencing.

Inflammatory pain, sustained by a complex network of inflammatory mediators, is a severe and persistent illness affecting many of the general population. We explore possible anti-inflammatory pathways of Polyphyllin VI (PPVI) based on our prior study, which showed that PPVI reduces inflammation in mice to reduce pain. Network pharmacology and RNA-Seq identified the contribution of the MAPK signaling pathway to inflammatory pain. In the LPS/ATP-induced RAW264.7 cell model, pretreatment with PPVI for 1 h inhibited the release of IL-6 and IL-8, down-regulated expression of the P2X7 receptor(P2X7R), and decreased phosphorylation of p38 and ERK1/2 components of the MAPK pathway. Moreover, PPVI decreased expression of IL-6 and IL-8 was observed in the serum of the inflammatory pain mice model and reduced phosphorylation of p38 and ERK1/2 in the dorsal root ganglia while the reductions of expression of IL-6 and phosphorylation of ERK1/2 were not observed after the pre-treatment with A740003 (an antagonist of the P2X7R). These results suggest that PPVI may inhibit the release of IL-8 by regulating P2X7R to reduce the phosphorylation of p38. However, the modulation of PPVI on the release of IL-6 and phosphorylation of ERK1/2 may mediated by other P2X7R-independent signals.

Polyphyllin VI screened from Chonglou by cell membrane immobilized chromatography relieves inflammatory pain by inhibiting inflammation and normalizing the expression of P2X3 purinoceptor.

Objective: Inflammatory pain is one of the most common diseases in daily life and clinic. In this work, we analysed bioactive components of the traditional Chinese medicine Chonglou and studied mechanisms of their analgesic effects. Material and methods: Molecular docking technology and U373 cells overexpressing P2X3 receptors combined with the cell membrane immobilized chromatography were used to screen possible CL bioactive molecules interacting with the P2X3 receptor. Moreover, we investigated the analgesic and anti-inflammatory effects of Polyphyllin VI (PPIV), in mice with chronic neuroinflammatory pain induced by CFA (complete Freund's adjuvant). Results: The results of cell membrane immobilized chromatography and molecular docking showed that PPVI was one of the effective compounds of Chonglou. In mice with CFA-induced chronic neuroinflammatory pain, PPVI decreased the thermal paw withdrawal latency and mechanical paw withdrawal threshold and diminished foot edema. Additionally, in mice with CFA-induced chronic neuroinflammatory pain, PPIV reduced the expression of the pro-inflammatory factors IL-1, IL-6, TNF-α, and downregulated the expression of P2X3 receptors in the dorsal root ganglion and spinal cord. Conclusion: Our work identifies PPVI as a potential analgesic component in the Chonglou extract. We demonstrated that PPVI reduces pain by inhibiting inflammation and normalizing P2X3 receptor expression in the dorsal root ganglion and spinal cord.

Combining antioxidant astaxantin and cholinesterase inhibitor huperzine A boosts neuroprotection.

Oxidative stress is a pathophysiological condition resulting in neurotoxicity, which is possibly associated with neurodegenerative disorders. In this study, the antioxidative effects of the antioxidant astaxanthin (AXT) in combination with huperzine A (HupA), which is used as a cholinesterase inhibitor for the treatment of Alzheimer's disease, were investigated. PC12 cells were treated with either tert­butyl hydroperoxide (TBHP), or with the toxic version of ß­amyloid, Aß25­35, to induce oxidative stress and neurotoxicity. Cell viability, morphology, lactate dehydrogenase (LDH) release, intracellular accumulation of reactive oxygen species (ROS), superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were determined, while neuroprotection was also monitored using an MTT assay. It was found that combining AXT with HupA significantly increased the viability of PC12 cells, prevented membrane damage (as measured by LDH release), attenuated intracellular ROS formation, increased SOD activity and decreased the level of MDA after TBHP exposure when compared to these drugs administered alone. Pretreatment with HupA and AXT decreased toxic damage produced by Aß25­35. These data indicated that combining an antioxidant with a cholinesterase inhibitor increases the degree of neuroprotection; with future investigation this could be a potential therapy used to decrease neurotoxicity in the brain.

Analgesic and antipruritic effects of oxymatrine sustained-release microgel cream in a mouse model of inflammatory itch and pain.

BACKGROUND: Allergic contact dermatitis (ACD) is a highly prevalent inflammatory and immune skin disease accompanied with persistent pruritus and pain. Oxymatrine (OMT) exhibits antipruritic and anti-inflammatory effects in squaric acid dibutyl ester (SADBE) induced ACD mice model, but the need for frequent administration stipulated by short half-life and low bioavailability limits clinical application. OBJECTIVE: To evaluate the analgesic and antipruritic effects of OMT gel (OG), OMT sustained release microgel powder (OMP) and OMT sustained release microgel cream (OMC) in SADBE induced ACD mice, with subsequent study of the mechanism and side effects (irritation) of optimal dosage form. METHOD: On day 11, the thickness of the right cheek skin of mice was measured and mice spontaneous behaviors were recorded for 1.5 h. In the OMC experiment, hematoxylin-eosin and toluidine blue staining were performed on the cheek skin, and the irritation of OMC was tested on the back skin of rabbits. Blood analyzer was used to measure the counts of inflammatory cells in peripheral blood. The mRNA expressions of IL-1ß, TNF-α, CXCR3, CXCL10, IL-6, IL-10, IL-17A and IL-31 in cheek skin, TRPA1 and TRPV1 channels in trigeminal ganglion (TG), IFN-γ in spleen and IL-17A in thymus were measured by RT-qPCR. RESULTS: OMC, OMP and OG significantly decreased wipes and scratching bouts, alleviated skin inflammation. OMC required less frequent administration and is easier to apply, while its antipruritic effect was stronger than the analgesic effect. OMC rescued the deficits in epidermal keratinization and inflammatory cell infiltration, decreased the leukocyte count in peripheral blood, had no irritation to the broken rabbit's skin. Furthermore, OMC significantly down-regulated the mRNA expression of IL-1ß, TNF-α, CXCR3, CXCL10, IL-6, IL-10, IL-17A and IL-31 in cheek skin, TRPA1 and TRPV1 channels in TG, IFN-γ in thymus and IL-17A in spleen. CONCLUSION: We have demonstrated that OMC exhibits advanced analgesic, antipruritic and anti-inflammatory effects when compared with OG and OMP in ACD mice by regulating inflammation, chemokines, immune mediators and inhibiting the mRNA expression of TRPA1 and TRPV1. OMC has no irritation to the intact and damaged skin of rabbits.