Researchers located in the United Kingdom say that levels of a hormone called B-type natriuretic peptide could have a role in reducing risk of Type 2 diabetes. The study was published online in the journal “PLoS Medicine.”
According to the research team, B-type natriuretic peptide, also called BNP, provides a variety of functions in the cardiovascular system: it mediates vasodilation, antifibrotic effects, and natriuresis. The researchers wrote that the hormone also has lipolytic activity and cross-sectional studies have indicated that BNP levels, or levels of the inactive fragment of its pro-hormone, N-terminal fragment of pro-BNP (NT-proBNP), are decreased in individuals who are obese or have Type 2 diabetes or insulin resistance.
The researchers conducted a prospective case-cohort study, using data from three case-control studies that involved patients who had been diagnosed with Type 2 diabetes. They used this data to determine if a connection existed between Type 2 diabetes and NT-proBNP in the bloodstream. The research team also genotyped the variant rs198389 within the BNP locus and used those results in a meta-analysis that used data from 11 case-control studies in all.
The multivariable analysis from the case-cohort study suggested that higher levels of NT-proBNP were correlated with decreased risk of Type 2 diabetes. For every increase of one standard deviation in blood levels of NT-proBNP, patients demonstrated a 21 percent reduction in risk of developing type 2 diabetes. The researchers adjusted for confounding factors, including age, sex, body-mass index, use of tobacco, hereditary history of Type 2 diabetes, hypertension, systolic blood pressure, and cholesterol levels (HDL, LDL and triglyceride).
The researchers stated that their estimates regarding the correlation between Type 2 diabetes and rs198389 were accurate.
“The association between rs198389 and type 2 diabetes observed in case-control studies (OR=0.94 per C allele; 95% CI, 0.91-0.97) was similar to that expected (OR=0.96; 95% CI, 0.93-0.98) based on the pooled estimate for the log-NT-proBNP level to type 2 diabetes association derived from a meta-analysis of our study and published data (HR=0.82 per SD; 95% CI, 0.74-0.9) and the difference in NT-proBNP levels (HR=0.22 per SD; 95% CI, 0.15-0.29) per C allele of rs198389,” wrote the team.
Additionally, there appeared to be no association between the rs198389 genotype and factors that may have confounded results, such as age, sex, and BMI. The researchers wrote that the findings demonstrate there may be a causal relationship between BNP and Type 2 diabetes, and the issue warrants further research. If a link is proven, it may open the door for therapeutics involving the manipulation of BNP activity to reduce risk of Type 2 diabetes. However, additional research will be needed before a definite causal link is established.
“The evidence for a potential causal link between the BNP hormone system and type 2 diabetes also promotes BNP as a potentially interesting target of preventive interventions. Influencing BNP activity by pharmaceutical interventions has been proven to be feasible in the context of CV medicine,” they wrote.
BNP is secreted by the ventricles of the heart as a response mechanism to excessive stretching of cardiomyocytes—the cells that make up heart muscle tissue. Secretion of BNP is related to several physiological processes, including the reduction of central venous pressure and systemic vascular resistance. Secretion of BNP also promotes natriuresis, the process by which the kidneys excrete sodium through urine. Natriuresis reduces the sodium content of the blood by expelling it through urine.