Phoneutria nigriventer, locally known as the Brazilian Wandering Spider, is one of the deadliest spiders that we know of. When stung, an individual experiences increased pulse, blood pressure and respiratory rate; extraordinary pain; a penile erection that lasts for at least 4 hours; and, in several cases, even death.
The venom of the P. nigriventer, also called the Banana spider, contains 6 neurotoxins that fall under the umbrella of PhTx3 (Tx3-1 through Tx3-6). Their mechanism involves blocking Calcium channels, inhibitng Glutamate release and aiding in an excitatory Serotonin response which triggers a cascade of Substance P, causing inflammation and intense pain.
As a single bite can also result in priapism (an erection for at least 4 hours), the component Tx2-6 of the venom is now being further studied to treat erectile differences ((ED); note that I use the phrase "erectile differences" instead of "erectile dysfunction"). The venomous components work by releasing Nitric Oxide, aiding in longer standing erections (a process adopted by Viagra).
Around 30% of people do not respond to Viagra or Cialis. The market has been looking for a genuine Viagra alternate for years.
Universidade Federal de Minas Gerais, Brazil took it a step further by giving us BZ-371A, a synthetic protein resembling the venomus components responsible for long erections. It is now begun Biozeus's Phase II trials in humans and has been through pre-clinical trials to treat Diabetic retinopathy, Dry age-related macular degeneration, Eye disorders, Glaucoma, Lung disorders and Optic nerve disorders.
Trials are expected to end in April 2024, so stay tuned to find out if we have found a genuine Viagra alternate.
Silva, C., et. al. PnPP-19, a Synthetic and Nontoxic Peptide Designed from a Phoneutria nigriventer Toxin, Potentiates Erectile Function via NO/cGMP. Journal of Urology. 2015. https://doi.org/10.1016/j.juro.2015.06.081
Natural Viagra: Spider bite causes prolonged erection. Live Science, April 30, 2007.
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