GsMTx4

GsMtx4, a peptide isolated from tarantula venom that selectively inhibits SACs and that has effectively suppressed stretch-induced atrial fibrillation in perfused rabbit hearts might circumvent this limitation. Inhomogeneous local mechanical stresses due to hypercontracture and swelling during ischemic reperfusion injury (IRI) likely induce elevated MSC activity that can contribute to cation imbalance.   >> Read More

Grammastola spatulata mechanotoxin #4 (GsMTx4) is a 35 amino acid peptide that inhibits the gating of cation selective MSCs with similar affinity in either the l or d enantiomic forms, emphasizing its lack of stereospecificity when interacting with MSCs. Cationic MSCs may belong to the Transient Receptor Potential (TRP) and/or Piezo families known to be expressed in cardiomyocytes and vascular tissue. In vitro measures of MSC activity in cardiac tissue, single cells and patch assays, show GsMTx4 activity in the range of 0.1–5 μM. GsMTx4 is a gating modifier that inhibits MSCs by clamping the membrane tension of the outer monolayer where its penetration depth, and thus its surface area contribution, is tension dependent.

GsMTx4-D is a cardioprotectant against myocardial infarction during ischemia and reperfusion