Dataset Information

Divanillyl sulfone suppresses NLRP3 inflammasome activation via inducing mitophagy to ameliorate chronic neuropathic pain in mice.

ABSTRACT:

Background

Chronic neuropathic pain is a frequent sequel to peripheral nerve injury and maladaptive nervous system function. Divanillyl sulfone (DS), a novel structural derivative of 4,4'-dihydroxydibenzyl sulfoxide from a traditional Chinese medicine Gastrodia elata with anti-nociceptive effects, significantly alleviated neuropathic pain following intrathecal injection. Here, we aimed to investigate the underlying mechanisms of DS against neuropathic pain.

Methods

A chronic constrictive injury (CCI) mouse model of neuropathic pain induced by sciatic nerve ligation was performed to evaluate the effect of DS by measuring the limb withdrawal using Von Frey filament test. Immunofluorescence staining was used to assess the cell localizations and expressions of Iba-1, ASC, NLRP3, and ROS, the formation of autolysosome. The levels of NLRP3-related proteins (caspase-1, NLRP3, and IL-1β), mitophagy-related proteins (LC3, Beclin-1, and p62), and apoptosis-related proteins (Bcl-XL and Bax) were detected by Western blotting. The apoptosis of BV-2 cell and caspase activity were evaluated by flow cytometry.

Results

DS significantly alleviated the neuropathic pain by increasing the mechanical withdrawal threshold and inhibiting the activation of NLRP3 in CCI-induced model mice. Our findings indicated that DS promoted the mitophagy by increasing the LC3II and Beclin 1 and decreasing the levels of p62 protein in BV-2 cell. This is accompanied by the inhibition of NLRP3 activation, which was shown as inhibited the expression of NLRP3 in lysates as well as the secretion of mature caspase-1 p10 and IL-1β p17 in supernatants in cultured BV-2 microglia. In addition, DS could promote mitophagy-induced improvement of dysfunctional mitochondria by clearing intracellular ROS and restoring mitochondrial membrane potential.

Conclusion

Together, our findings demonstrated that DS ameliorate chronic neuropathic pain in mice by suppressing NLRP3 inflammasome activation induced by mitophagy in microglia. DS may be a promising therapeutic agent for chronic neuropathic pain.

SUBMITTER: Shao S

PROVIDER: S-EPMC8223331 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Background Paclitaxel is commonly used as a cancer chemotherapy drug that frequently causes peripheral neuropathic pain. Inflammasome is a multiprotein complex consisting of Nod-like receptor proteins (NLRPs), apoptosis-associated speck-like protein, and caspase-1, which functions to switch on the inflammatory process and the release of interleukin-1?. Growing evidences have supported that peripheral interleukin-1? is critical in enhancing paclitaxel-induced neuropathic pain. However, whether activation of NLRP3 inflammasome in peripheral nerve contributes to paclitaxel-induced neuropathic pain is still unclear. Results Paclitaxel induced mechanical allodynia of rats from day 3 and worsened gradually till 3 weeks after injection. Paclitaxel resulted in expression of NLRP3 and activated fragments of caspase-1 and interleukin-1? in L4-6 dorsal root ganglia and sciatic nerve three weeks after injection, indicating activation of NLRP3 inflammasome. The expression of NLRP3 was located in CD68-labeled macrophages infiltrating in L4-6 dorsal root ganglia and sciatic nerve, and paclitaxel increased the expression of NLRP3 in macrophage. Moreover, the paclitaxel elicited mitochondria damage, which became swollen and enlarged in macrophages and axons of sciatic nerve three weeks after injection. In vitro, paclitaxel increased the number of damaged mitochondria and mitochondrial reactive oxygen species production in the rat alveolar macrophage cell line NR8383. The administration of a non-specific reactive oxygen species scavenger, phenyl-N-tert-butylnitrone, markedly alleviated mechanical allodynia and inhibited the activation of NLRP3 inflammasome in L4-6 dorsal root ganglia and sciatic nerve of the paclitaxel-induced neuropathic pain model. Conclusions Paclitaxel induced mechanical allodynia and activation of NLRP3 inflammasome in infiltrated macrophages of L4-6 dorsal root ganglia and sciatic nerve. Paclitaxel elicited mitochondria damage and reactive oxygen species production may result in activation of NLRP3 inflammasome in peripheral nerve, which contributes to paclitaxel-induced neuropathic pain.