Effects of Potassium Bicarbonate Supplements on Circulating microRNA Expression

Area of Science:

• Biochemistry
• Gerontology
• Nutritional Science

Background:

• Dietary acid load is implicated in musculoskeletal health decline.
• Alkali supplementation may counteract negative effects of acid load.
• MicroRNAs (miRNAs) are emerging biomarkers for bone and muscle metabolism.

Purpose of the Study:

• To investigate the effects of potassium bicarbonate (KHCO3) supplementation on serum microRNAs.
• To assess changes in biomarkers of bone metabolism and acid-base balance.
• To explore the relationship between microRNAs and bone resorption markers.

Main Methods:

• A randomized controlled trial involving 24 older adults (12 KHCO3, 12 placebo) for 84 days.
• Measurements included serum microRNAs, urinary net acid excretion (UNAE), urinary N-telopeptide (UNTX), urinary calcium (UCa), and serum P1NP.
• Statistical analyses compared changes between groups and correlated miRNA expression with biomarker changes.

Main Results:

• Potassium bicarbonate significantly reduced UNAE, UNTX, UCa, and serum P1NP compared to placebo.
• Serum levels of microRNA-133b (c-miR-133b) and microRNA-21-5p (c-miR-21-5p) significantly increased in the KHCO3 group.
• Increased c-miR-133b and c-miR-21-5p were inversely associated with UNAE, UNTX, and UCa, indicating reduced bone resorption.

Conclusions:

• Reducing dietary acid load with KHCO3 supplementation is associated with increased expression of specific circulating microRNAs.
• These microRNAs may serve as biomarkers reflecting reduced bone resorption and potential benefits for bone health in older adults.
• Further research is needed to confirm the role of these microRNAs in musculoskeletal health.