Ivermectina: ¿Un antiparasitario frente a SARS-CoV-2? / Ivermectin: an antiparasitic drug to fight SARS-CoV-2?

RESUMEN La capacidad de propagación y letalidad del SARS-CoV-2 en todo el mundo motiva la urgente necesidad de desarrollar una estrategia terapéutica apropiada para controlar los casos de COVID-19. El desarrollo de nuevos fármacos frente a este nuevo virus es apremiante debido a su rápida diseminación. Se han propuesto alternativas paralelas empleando fármacos ya disponibles para fines similares. Esta revisión describe el potencial antiviral de la ivermectina, así como sus mecanismos de acción frente a algunos virus, y discute su probable aplicación contra el SARS-CoV-2.

ABSTRACT The global spread and lethality of SARS-CoV-2 prompt the urgent need to develop an appropriate therapeutic strategy to control COVID-19 cases. The development of new drugs to fight this novel virus is urgent due to its rapid spread. Parallel alternatives have been proposed by using drugs already available for similar purposes. This review article describes the antiviral potential of ivermectin as well as its mechanisms of action against some viruses, and discusses its probable use to fight SARS-CoV-2.

Nanoelectrochemical Study of Molecular Transport through the Nuclear Pore Complex.

The nuclear pore complex (NPC) is the proteinaceous nanopore that solely mediates the transport of both small molecules and macromolecules between the nucleus and cytoplasm of a eukaryotic cell to regulate gene expression. In this personal account, we introduce recent progress in our nanoelectrochemical study of molecular transport through the NPC. Our work represents the importance of chemistry in understanding and controlling of NPC-mediated molecular transport to enable the efficient and safe delivery of genetic therapeutics into the nucleus, thereby fundamentally contributing to human health. Specifically, we employ nanoscale scanning electrochemical microscopy to test our hypothesis that the nanopore of the NPC is divided by transport barriers concentrically into peripheral and central routes to efficiently mediate the bimodal traffic of protein transport and RNA export, respectively, through cooperative hydrophobic and electrostatic interactions.

Nuclear proteasomal degradation of Saccharomyces cerevisiae inorganic pyrophosphatase Ipp1p, a nucleocytoplasmic protein whose stability depends on its subcellular localization.

Inorganic pyrophosphate (PPi) is an abundant by-product of cellular metabolism. PPi-producing reactions take place in the nucleus concurrently with reactions that use PPi as a substrate. Saccharomyces cerevisiae possesses two soluble pyrophosphatases (sPPases): Ipp1p, an essential and allegedly cytosolic protein, and Ipp2p, a mitochondrial isoenzyme. However, no sPPase has yet been unambiguously described in the nucleus. In vivo studies with fluorescent fusions together with activity and immunodetection analyses demonstrated that Ipp1p is a nucleocytoplasmic protein. Mutagenesis analysis showed that this sPPase possesses a nuclear localization signal which participates in its nuclear targeting. Enforced nucleocytoplasmic targeting by fusion to heterologous nuclear import and export signals caused changes in polypeptide abundance and activity levels, indicating that Ipp1p is less stable in the nucleus that in the cytoplasm. Low nuclear levels of this sPPase are physiologically relevant and may be related to its catalytic activity, since cells expressing a functional nuclear-targeted chimaera showed impaired growth and reduced chronological lifespan, while a nuclear-targeted catalytically inactive protein was not degraded and accumulated in the nucleus. Moreover, nuclear proteasome inhibition stabilized Ipp1p whereas nuclear targeting promoted its ubiquitination and interaction with Ubp3p, a component of the ubiquitin-proteasome system. Overall, our results indicate that Ipp1p is nucleocytoplasmic, that its stability depends on its subcellular localization and that sPPase catalytic competence drives its nuclear degradation through the ubiquitin-proteasome system. This suggests a new scenario for PPi homeostasis where both nucleocytoplasmic transport and nuclear proteasome degradation of the sPPase should contribute to control nuclear levels of this ubiquitous metabolite.