The Association Between Serum β-hydroxybutyrate and Levels of Systemic Hypertension: "An Open-label Randomized Controlled Trial.

Systemic hypertension is defined as a systolic blood pressure that is ≥ 140 mm hg and / or a diastolic blood pressure that is ≥ 90 mm hg a modifiable and it is known to be a serious risk factor for cardiovascular disease. Exercise is widely recommended as a lifestyle modification for hypertensive patients because of its beneficial effect on lowering blood pressure (BP). Similarly, calorie restriction is also documented to lower systemic hypertension.

Interestingly, both exercise and calorie-restriction are associated with increased circulating levels of ketone bodies such as β-hydroxybutyrate (βHB). β-Hydroxybutyrate (βHB; 3-hydroxybutyric acid) is a "ketone body" which is produced the liver, mainly from the oxidation of fatty acids, and is exported to peripheral tissues for use as an energy source. It is transported to extrahepatic tissues, and traditionally recognized as a vital alternative source of energy during starvation. However, recent evidences indicate that apart from serving as energy fuel, ketone bodies such as βHB block nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (Nlrp3)-inflammasome-mediated inflammatory diseases, and thereby play a prominent role in maintaining physiological homeostasis parameter such as blood pressure.

Among environmental factors, excessive salt intake is the most common and important risk factor for hypertension, in which patient with salt-sensitive hypertension demonstrated an increased risk of cardiovascular disease. There is substantial evidence suggesting that blood pressure's (BP) response to dietary salt intake vary considerably among individuals which is a phenomenon described as salt sensitivity of blood pressure.

Another reference demonstrated a lower circulating level of the ketone body, beta-hydroxybutyrate (βHB), in high salt-fed hypertensive rats. Despite the high salt intake, the specific rescue of (βHB) levels by nutritional supplementation of its precursor, 1,3-butanediol, attenuates hypertension and protects kidney function by inhibiting the renal Nlrp3 inflammasome in rats.

Existing Knowledge and Literature Review: PubMed search builder was used to construct the following search entry: hypertension AND β-Hydroxybutyrate. The initial search yielded 39 titles. Studies (RCTs or systemic reviews) relevant to the research question were isolated manually by reading the abstracts. However, due to the novelty of the idea, the investigators were not able to identify any related literature except of "Chakraborty, Saroj" study. which was a non-human research.