According to numerous studies, flavonoids pose a threat to bacteria, fungi and viruses, but they offer only benefits to animal and human cells. Today, flavonoids are extracted from plants to be used in nutraceuticals, medicines and even cosmetics. Some of the most notable health-promoting properties of flavonoids include antioxidant, anti-inflammatory, anti-mutagenic, anti-cancer and cardioprotective properties.
But in a recent study, researchers the Institute Butantan in Brazil found that flavonoids can also be used to treat poisonous snakebites. Specifically, they identified the flavonoid rutin, which is present in apples and buckwheat, as a promising treatment for envenomation by the lancehead pit viper (Bothrops jararaca). The venom from this viper is known to cause blood clotting problems, which can lead to fatal embolism.
The researchers discussed their findings in an article published in the journal PLOS Neglected Tropical Diseases.
The chemical rutin is usually found in popular fruits and vegetables, such as strawberries, bell peppers, chili peppers, blackberries, grapes, figs and black and green tea. In plants, rutin not only functions as part of their defense mechanisms, but it also helps filter ultraviolet rays and fixes nitrogen. Research has found that rutin is a potent antioxidant and anti-inflammatory agent.
Despite the lack of guidelines for the use of rutin, it is a common medicinal component. Rutin is listed as an ingredient in more than 130 registered medicinal preparations. Among the many benefits offered by rutin, it is best known for boosting cardiovascular health by improving blood circulation, preventing blood clots and lowering blood cholesterol. Rutin also strengthens and increases the flexibility of blood vessels, thus improving overall health.
Another health benefit linked to rutin is pain relief, which scientists attribute to its ability to reduce inflammation and fight oxidative stress.
The lancehead pit viper is a highly venomous species endemic to South America. It is responsible for about 70 percent of snakebites reported in Sao Paolo. Although antivenoms are known to counteract the main effects of snakebites, they cannot treat secondary complications. In the case of B. jararaca envenomation, the victim becomes at risk of developing embolisms or suffering from a stroke due to the activity of the viper's venom.
Inside the body, the venom produced by B. jararaca increases the activity of a protein known as platelet tissue factor. This protein is involved in blood clotting and is known to activate the formation of thrombin, an enzyme that can either promote or suppress coagulation. In the presence of a cut or wound, the affected tissue normally recruits platelet tissue factor to initiate the clotting process and stop the bleeding.
However, B. jararaca's venom activates platelet tissue factor even in the absence of tissue or blood vessel injury. This triggers the formation of blood clots, which can turn into embolisms that can clog blood vessels and lead to tissue necrosis or even stroke.
But in their study, the Brazilian researchers found that the flavonoid rubin can stop blood clotting induced by B. jararaca venom by stopping the activity of the enzyme protein disulfide isomerase (PDI). PDI is produced by platelets and damaged epithelial cells in order to activate platelet tissue factor and initiate the blood clotting process.
Because of this activity, the researchers believe that rubin from common plant-based foods is a promising natural medicine that can prevent secondary complications of snakebites, such as thrombosis.