HIBCH Human

3-Hydroxyisobutyryl-CoA Hydrolase (HIBCH) is an enzyme that plays a crucial role in the metabolism of certain amino acids. It is specifically involved in the degradation of valine, leucine, and isoleucine, which are branched-chain amino acids. The enzyme is encoded by the HIBCH gene in humans .

HIBCH catalyzes the hydrolysis of 3-hydroxyisobutyryl-CoA to 3-hydroxyisobutyrate and Coenzyme A (CoA). This reaction is a part of the valine degradation pathway, which is essential for energy production and various metabolic processes . The systematic name of this enzyme is 3-hydroxy-2-methylpropanoyl-CoA hydrolase .

The enzyme participates in several metabolic pathways:

• Valine, Leucine, and Isoleucine Degradation: These pathways are crucial for the breakdown of branched-chain amino acids, which are important for muscle metabolism and energy production .
• β-Alanine Metabolism: This pathway is involved in the production of β-alanine, a precursor for the synthesis of carnosine, which helps buffer acid in muscles .
• Propanoate Metabolism: This pathway is involved in the conversion of propionate to succinate, which enters the citric acid cycle for energy production .

Mutations in the HIBCH gene can lead to a deficiency in the enzyme, resulting in a metabolic disorder known as 3-Hydroxyisobutyryl-CoA Hydrolase Deficiency. This condition can cause a range of symptoms, including developmental delay, muscle weakness, and metabolic acidosis . Additionally, the enzyme’s activity has been linked to conditions such as insulin resistance and type 2 diabetes .

Recent research has highlighted the role of HIBCH in regulating hepatic lipid accumulation and its potential implications for fatty liver disease . Understanding the enzyme’s function and regulation can provide insights into metabolic diseases and offer potential targets for therapeutic intervention.