ω-Grammotoxin-SIA inhibits voltage-gated Na+ channel currents.

ω-Grammotoxin-SIA (GrTX-SIA) was originally isolated from the venom of the Chilean rose tarantula and demonstrated to function as a gating modifier of voltage-gated Ca2+ (CaV) channels. Later experiments revealed that GrTX-SIA could also inhibit voltage-gated K+ (KV) channel currents via a similar mechanism of action that involved binding to a conserved S3-S4 region in the voltage-sensing domains (VSDs). Since voltage-gated Na+ (NaV) channels contain homologous structural motifs, we hypothesized that GrTX-SIA could inhibit members of this ion channel family as well.

Understanding the physiological role of Na1.9: Challenges and opportunities for pain modulation.

Voltage-activated Na (Na) channels are crucial contributors to rapid electrical signaling in the human body. As such, they are among the most targeted membrane proteins by clinical therapeutics and natural toxins. Several of the nine mammalian Na channel subtypes play a documented role in pain or other sensory processes such as itch, touch, and smell.

Malignant neoplasm of breast in Brazilian women: A cross-sectional study from 2008 to 2019.

Objective: Breast cancer is the most lethal malignancy for women worldwide. Developed countries, such as Portugal, Spain, and the United States, have declining mortality rates due to breast cancer; however, in developing countries, the epidemiological reports are scarce. In this context, the aims of this study are to describe and discuss the female breast cancer profile of hospitalization and mortality according to age and geographic region in Brazil from 2008 to 2019.

Neurotoxicity of Olindias sambaquiensis and Chiropsalmus quadrumanus extracts in sympathetic nervous system.

Cnidarians are equipped with nematocysts, which are specialized organelles used to inoculate venom during prey capturing and defense. Their venoms are rich in toxins and a potential source of bioactive compounds, however, poorly explored so far. In this work, the activity of the methanolic extracts from the hydromedusa Olindias sambaquiensis and the cubozoan jellyfish Chiropsalmus quadrumanus were studied in sympathetic neurotransmission.

The Influence of Silver Nanoparticles Against Toxic Effects of Venom.

Purpose: A silver nanoparticle obtained by reducing salts with solid dispersion of curcumin (130 nm, 0.081 mg mL) was used to counteract against the toxic - edematogenic, myotoxic, and neurotoxic - effects of venom.

Methods: The edematogenic effect was evaluated by plasma extravasation in rat dorsal skin after injection of 50 µg per site of venom alone or preincubated with 1, 10, and 100 µL of AgNPs; the myotoxicity was evaluated by measuring the creatine kinase released into the organ-bath before the treatment and at the end of each experiment; and neurotoxicity was evaluated in chick biventer cervicis using the conventional myographic technique, face to the exogenous acetylcholine (ACh) and potassium chloride (KCl) added into the bath before the treatment and after each experiment.