Beverly Chimene

Introduction: Hypertension is defined as having blood pressure measured above 140 mmHg systolic or 90 mmHg diastolic. ¹ Specific hypertensive conditions are categorized by the severity or consistency of the rise in blood pressure. Hypertension is a leading risk factor for Cardiovascular disease and effects over a billion people worldwide. ^2,3 This disease is common place in the healthcare community, but still almost half of the diagnosed patients’ hypertension are uncontrolled due to ineffective treatments and the complex mechanisms of blood pressure. The standard antihypertensive medications target multiple systems including the autonomic nervous system and kidney regulation.⁴ However, new prominent hypertensive research is focusing on the endogenous gasotransmitter, Hydrogen Sulfide (H₂S), for its vasodilatory functions.  Methods: Various studies have been conducted to investigate H₂S’s mechanism of action and concentrations relative to pathologic effects. Commonly, the main H₂S producing enzymes, cystathionine γ-lyase (CSE) and Cystathionine β-synthase (CBS), were genetically manipulated to knock-out H₂S in live models to determine the impact on vasorelaxation.⁵ Additionally, H₂S donors, Na₂S, NaHS, and sodium thiosulfate (STS), were compared to placebos in order to view effects on vascular smooth muscles in several pathologies, including cardiac and hepatic injuries and portal hypertension.^5,6  Results: Researchers analyzing apoptotic activity in hepatocytes found that H₂S is involved in inhibiting anti-apoptotic genes to allow for reconstruction of blood vessels and smooth muscle cells.⁶ This action allows for control over extracellular matrix and collagen production ensuring the continued compliance necessary for healthy blood pressure. H₂S’s protective actions were found to extend to pathologic conditions. Results from King et al. show the presence of H₂S minimized injuries from cirrhotic ischemia.⁵ This was further supported by a study that determined pretreatment with H₂S decreased the effects of oxidative stress by reactive oxygen species.⁷ In order to branch findings to possible treatment options, researchers analyzed STS effectiveness as a H₂S donor specifically targeting the Renin-Angiotensin-Aldosterone system. STS prevented hypertension in rat models and promoted additional vasodilation mechanisms.   Conclusion: H₂S shows various antihypertensive properties and beneficial cardiovascular protective qualities. With further exploration, H₂S may be a valuable treatment option for hypertension and cardiovascular diseases.

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3. Tayefi, Maryam, Habibollah Esmaeili, Maryam Saberi Karimian, Alireza A. Zadeh, Mahmoud Ebrahimid, Mohammad Safarian, Mohsen Nematy, and Seyed Mohammad Reza Parizadeh. “The application of a decision tree to establish the parameters associated with hypertension.”Computer Methods and Programs in Biomedicine 139 (2017): 83-91. Web.
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