The underlying mechanism of scorpion venom peptide BmK AS in reducing epilepsy seizures: mediated through dual modulation of Nav1.6 and the inflammasome pathway

Posted by
  The underlying mechanism of scorpion venom peptide BmK AS in reducing epilepsy seizures: mediated through dual modulation of Nav1.6 and the inflammasome pathway Abstract Introduction:  Voltage-gated sodium channel (VGSC) dysregulation, particularly of the Nav1.6 subtype, is a core mechanism underlying epileptogenesis and its associated neuropsychiatric comorbidities. The scorpion venom peptide BmK AS has demonstrated anticonvulsant potential, but its efficacy in chronic epilepsy and the precise mechanisms of action remain undefined. Methods:  Here, we show that BmK AS exerts robust anti-epileptic and neuroprotective effects through converging mechanisms. In a kainic acid-induced mouse model, BmK AS treatment reduced mortality and seizure parameters. Electrophysiological studies assessed BmK AS modulation of VGSC subtypes. The functional relevance of Nav1.6 targeting was confirmed by the loss of BmK AS’s anti-seizure efficacy upon its pharmacological blockade in a PTZ-in...

Discovering unknown Madagascar biodiversity: integrative taxonomy of raft spiders (Pisauridae: Dolomedes)

Posted by

 


Discovering unknown Madagascar biodiversity: integrative taxonomy of raft spiders (Pisauridae: Dolomedes)

Abstract



Madagascar is a global biodiversity hotspot, but its biodiversity continues to be underestimated and understudied. Of raft spiders, genus Dolomedes Latreille, 1804, literature only reports two species on Madagascar. Our single expedition to humid forests of eastern and northern Madagascar, however, yielded a series of Dolomedes exemplars representing both sexes of five morphospecies. To avoid only using morphological diagnostics, we devised and tested an integrative taxonomic model for Dolomedes based on the unified species concept. The model first determines morphospecies within a morphometrics framework, then tests their validity via species delimitation using COI. It then incorporates habitat preferences, geological barriers, and dispersal related traits to form hypotheses about gene flow limitations. Our results reveal four new Dolomedes species that we describe from both sexes as Dolomedes gregoric sp. nov., D. bedjanic sp. nov., D. hydatostella sp. nov., and D. rotundus sp. nov. The range of D. kalanoro Silva & Griswold, 2013, now also known from both sexes, is expanded to eastern Madagascar. By increasing the known raft spider diversity from one valid species to five, our results merely scratch the surface of the true Dolomedes species diversity on Madagascar. Our integrative taxonomic model provides the framework for future revisions of raft spiders anywhere.

Yu K, Kuntner M. 2024. Discovering unknown Madagascar biodiversity: integrative taxonomy of raft spiders (Pisauridae: Dolomedes) PeerJ 12:e16781