Seven novel modulators of the analgesic target NaV1.7 uncovered using a high-throughput venom-based discovery approach

摘要: Background and Purpose Chronic pain is a serious worldwide health issue, with current analgesics having limited efficacy dose-limiting side effects. Humans loss-of-function mutations in the voltage-gated sodium channel NaV1.7 (hNaV1.7) are indifferent to pain, making hNaV1.7 promising target for analgesic development. Since spider venoms replete NaV modulators, we examined their potential as source of inhibitors. Experimental Approach We developed high-throughput fluorescent-based assay screen against isolate ‘hit’ peptides. To examine binding site these peptides, constructed panel chimeric channels which S3b-S4 paddle motif from each voltage sensor domain was transplanted into homotetrameric KV2.1 channel. Key Results We screened 205 found that 40% contain at least one inhibitor hNaV1.7. By deconvoluting venoms, discovered seven novel members NaSpTx family 1. One Hd1a (peptide μ-TRTX-Hd1a venom Haplopelma doriae), inhibited high level selectivity over all other subtypes, except hNaV1.1. We showed gating modifier inhibits by interacting II. The structure Hd1a, determined using heteronuclear NMR, contains an cystine knot likely confer levels chemical, thermal biological stability. Conclusion Implications Our data indicate rich natural inhibitors might be useful leads development analgesics.