How a Brazilian snake's venom led to a widely used blood pressure drug

(Image credit: Wikimedia Commons)Long before modern medical science emerged, nature held answers to healing, protection and healthy living within its bounds. Across several communities and spiritual cosmologies, the natural world has been viewed as the guide for the human world, as have the species that reside in it. Among the myriad spcies that have been a major subject of scientifc study, the animal venom has held serious importance. Therefore, native to parts of South American, including Brazil, a pit viper that possesses harmful venom was researched in the 1960s. The snake in question was Bothrops jararaca, commonly known as the Brazilian lancehead or jararaca.(Image credit: Canva) As researchers investigated its biolgical effects, they discovered compounds that would help shape the evolution of a new class of medicine, soemthing that would go on to change the use of western drugs in cardiovascular medicine, as this pit viper went on to change the treatment of blood pressure. With this seminal discovery, a research led a new pathway for a harmful substance to become a paramount drug. This work contributd to the development of captopril, an oral drug approved in the United states in 1981 for treating hypertension.The discovery hidden in snake venomThe research began sometime in the year 1965 with a young Brazilian pharmacologist, Sergio Ferreira, who published a paper, that was based on his PhD thesis, in the British Journal of Pharmacology . He described the properties of an extract of snake venom where he desrcibred the potential properties, of a snake venom and indetified a substance that enhanced the effects of bradykinin, a naturally occuring peptide that involved in wideing blood vessels and subsequently lowering blood pressure.Captopril: ball and stick model (Image credit: Wikimedia Commons) Further investigation revealed that the venom contained small molecules called bradykinin-potentiating peptides. These findings became particularly important as scientists established how the peptides interacted with the body's blood-pressure-regulating systems. One enzyme that recieved considerable attention: angiotensin-converting enzyme, commonly known as ACE. Under normal circumstances, ACE helps convert angiotensin I into angiotensin II, a substance that constricts blood vessels and contributes to an increase in blood pressure. The enzyme also breaks down bradykinin, which helps blood vessels relax.From venom peptide to a medicineUnderstanding the biological effects of the venom was only the beginning. The challenge was to turn those findings into a medicine that patients could take reliably. Researchers discovered that the venom-derived peptide teprotide could inhibit ACE and lower blood pressure. However, teprotide could not be administered orally, making it less practical for routine treatment. Scientists needed a different compound that could reproduce the desired effect while being suitable for use as a tablet. Captopril became the first ACE inhibitor approved by the United States Food and Drug Administration in 1981. Its development marked an important milestone in pharmacology, demonstrating how observations made in nature could guide the design of medicines for human use.Why this discovery still mattersHigh blood pressure, or hypertension, can place sustained strain on the heart and blood vessels, increasing the risk of serious cardiovascular complications. Because the condition may develop without obvious symptoms, treatment often depends on identifying elevated blood pressure and managing it over time.Captopril has offered new ways of responding to this problem by targeting the biological processes that are involved in regulating blood pressure. It became a vital medicine in the treatment of hypertension, and ACE inhibitors subsequently developed into an established class of cardiovascular drugs. These medicines are also used in other clinical settings, including certain cases of heart failure and kidney disease, depending on the individual patient's condition.However, the research on snake venom doesnt propogate the use of snake venom itself as a replacement of a prescribed drug. While, the venom has been able to rpovide researches with a biological clue, the years of researhc, experiemntation and development has enabled the drug to be established for use today.From a Brazilian pit viper to a laboratory designed pill, the journey of captopril has been long. However, the 15-20 years spent between the research and the drug's approval saw the field of medical science evolve. Today, decades later, multiple researchers around the world attest to how the natural world has opened many doors for discovery that would have otherwise remained out of reach.