Race, Natriuretic Peptides, and High-Carbohydrate Challenge: A Clinical Trial

Circ Res. 2019 Nov 8;125(11):957-968. doi: 10.1161/CIRCRESAHA.119.315026. Epub 2019 Oct 6.

Abstract

Rationale: Lower NP (natriuretic peptide) levels may contribute to the development of cardiometabolic diseases. Blacks have lower NP levels than middle-aged and older white adults. A high-carbohydrate challenge causes an upregulation of a negative ANP regulator microRNA-425 (miR-425), which reduces ANP (atrial-NP) levels in whites.

Objectives: We designed a prospective trial to study racial differences in (1) NP levels among young adults, (2) NP response to a high-carbohydrate challenge, and (3) explore underlying mechanisms for race-based differences.

Methods and results: Healthy self-identified blacks and whites received 3 days of study diet followed by a high-carbohydrate challenge. Gene expression from whole blood RNA was assessed in the trial participants. Additionally, atrial and ventricular tissue samples from the Myocardial Applied Genomics Network repository were examined for NP system gene expression. Among 72 healthy participants, we found that B-type-NP, NT-proBNP (N-terminal-pro-B-type NP), and MRproANP (midregional-pro-ANP) levels were 30%, 47%, and 18% lower in blacks compared with whites (P≤0.01), respectively. The decrease in MRproANP levels in response to a high-carbohydrate challenge differed by race (blacks 23% [95% CI, 19%-27%] versus whites 34% [95% CI, 31%-38]; Pinteraction<0.001), with no change in NT-proBNP levels. We did not observe any racial differences in expression of genes encoding for NPs (NPPA/NPPB) or NP signaling (NPR1) in atrial and ventricular tissues. NP processing (corin), clearance (NPR3), and regulation (miR-425) genes were ≈3.5-, ≈2.5-, and ≈2-fold higher in blacks than whites in atrial tissues, respectively. We also found a 2-and 8-fold higher whole blood RNA expression of gene encoding for Neprilysin (MME) and miR-425 among blacks than whites.

Conclusions: Racial differences in NP levels are evident in young, healthy adults suggesting a state of NP deficiency exists in blacks. Impaired NP processing and clearance may contribute to race-based NP differences. Higher miR-425 levels in blacks motivate additional studies to understand differences in NP downregulation after physiological perturbations.

Clinical trial registration: URL: https://clinicaltrials.gov/ct2/show/NCT03072602. Unique identifier: NCT03072602.

Keywords: carbohydrate; gene expression; glucose; microRNA; natriuretic peptide.

Publication types

  • Clinical Trial
  • Comparative Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • African Americans*
  • Alabama
  • Atrial Natriuretic Factor / blood*
  • Atrial Natriuretic Factor / genetics
  • Biomarkers / blood
  • Cell Line
  • Dietary Carbohydrates / administration & dosage*
  • Dietary Carbohydrates / metabolism
  • Down-Regulation
  • European Continental Ancestry Group*
  • Female
  • Health Status Disparities*
  • Healthy Volunteers
  • Humans
  • Induced Pluripotent Stem Cells / metabolism
  • Male
  • Myocytes, Cardiac / metabolism
  • Natriuretic Peptide, Brain / blood*
  • Natriuretic Peptide, Brain / genetics
  • Peptide Fragments / blood*
  • Peptide Fragments / genetics
  • Prospective Studies
  • Race Factors
  • Time Factors

Substances

  • Biomarkers
  • Dietary Carbohydrates
  • Peptide Fragments
  • midregional pro-atrial natriuretic peptide, human
  • pro-brain natriuretic peptide (1-76)
  • Natriuretic Peptide, Brain
  • Atrial Natriuretic Factor

Associated data

  • ClinicalTrials.gov/NCT03072602