AaTs-1, a Tetrapeptide from Scorpion Venom Mitigates Demyelination and Neuroinflammation in a Cuprizone-Induced Model of Multiple Sclerosis

Posted by
  AaTs-1, a Tetrapeptide from Scorpion Venom Mitigates Demyelination and Neuroinflammation in a Cuprizone-Induced Model of Multiple Sclerosis Abstract Purpose This study focuses on the evaluation of the therapeutic potential of Tetrascorpin-1 (AaTs-1), a tetrapeptide isolated from Androctonus australis hector venom, proposed as a putative formyl peptide receptor 2 (FPR2) antagonist, in a cuprizone-induced murine model of Multiple sclerosis (MS), a chronic autoimmune and inflammatory disease of the central nervous system. Methods Acute demyelination was induced in mice by administering cuprizone (0.2% w/w in the diet) for six weeks. During the sixth week of cuprizone intake, demyelinated mice received intranasal administration of AaTs-1 at a dose of 50–100 µg/kg for five consecutive days, with 24-hour intervals between treatments. Results Behavioral assessments, immunological assays, and histological analyses revealed that AaTs-1 improved body weight, reduced behavioral impairments...

Revisiting and rediscovering the tarantulas (Araneae, Theraphosidae) of Culapnitan (Libmanan) Caves in the Philippines: troglomorphism, taxonomy, phylogeny and ecological niche

Posted by

 


Revisiting and rediscovering the tarantulas (Araneae, Theraphosidae) of Culapnitan (Libmanan) Caves in the Philippines: troglomorphism, taxonomy, phylogeny and ecological niche

Abstract

In 1892, French naturalist Eugène Simon described samples of cave-dwelling tarantula species collected from Culapnitan Caves in the Philippines, a cave system that is now part of the present-time Libmanan Caves Natural Park (LCNP). One of these is the new monotypic tarantula genus and species of that time, Orphnaecus pellitus Simon, 1892. Based on Simon’s notes and quick observation of the eyes of the syntypes, this species is highly suspected to be troglobitic. In the present study, we rediscovered O. pellitus from its reported site and investigated its troglobitic characteristics. Morphological analysis of O. pellitus shows troglomorphic characteristics which include reduced eye size, attenuated limbs, shortened tactile setae, and diminishing pigmentation. Tolerance to hypoxia and heightened sensitivity to ground movements are the other subterranean adaptations that were observed. Phylogenetic analysis revealed a cladistic relationship among tarantula morphologically identified from the genus Orphnaecus. Our findings provide evidence that O. pellitus is a true troglobitic tarantula reported worldwide, and currently the only one known from Asia. We also report two new species of Orphnaecus, Orphnaecus libmanan sp. nov. and the dwarf Orphnaecus tangcongvaca sp. nov., collected from the forest grounds of the LCNP. The ecological niche differentiation of theraphosid species in the LCNP is also provided. Our findings are supported by morphology, molecular phylogeny, and ecology.

Acuña DC, Ragasa LRP, Santiago-Bautista MR, von Wirth V, Guevarra Jr LA (2025) Revisiting and rediscovering the tarantulas (Araneae, Theraphosidae) of Culapnitan (Libmanan) Caves in the Philippines: troglomorphism, taxonomy, phylogeny and ecological niche. Subterranean Biology 52: 143-186. https://doi.org/10.3897/subtbiol.52.142334