Coenzyme A and its thioester pools in fasted and fed rat tissues

Area of Science:

• Biochemistry
• Metabolomics
• Physiology

Background:

• Coenzyme A (CoA) and its derivatives, acetyl-CoA and malonyl-CoA, are crucial metabolic intermediates.
• Understanding the tissue-specific distribution and regulation of CoA pools is essential for comprehending energy metabolism.

Purpose of the Study:

• To comprehensively analyze the levels of nonesterified CoA (CoASH), acetyl-CoA, and malonyl-CoA in thirteen rat tissues.
• To investigate the impact of fasting and feeding on these CoA species across different tissues.
• To elucidate tissue-specific metabolic adaptations in response to nutritional status.

Main Methods:

• Utilized the acyl-CoA cycling method for sensitive detection of CoA molecular species at the picomole level.
• Analyzed CoA levels in various rat tissues under both fasted and fed conditions.
• Performed a comparative analysis across thirteen distinct tissue types.

Main Results:

• Feeding induced a significant increase in malonyl-CoA and a reciprocal decrease in acetyl-CoA in brain tissues, including the cerebral cortex, hippocampus, cerebellum, medulla oblongata, and hypothalamus.
• Non-brain tissues exhibited variable pool sizes for acetyl-CoA, malonyl-CoA, and CoASH.
• Liver, heart, and brown adipose tissue possessed larger total CoA pools compared to perirenal, epididymal, and ovarian adipose tissues.
• The response of CoA pools to feeding was not uniform across all tissues, indicating tissue-specific metabolic regulation.

Conclusions:

• Coenzyme A pools exhibit distinct sizes and dynamic responses to feeding and fasting across different rat tissues.
• Brain tissue demonstrates a specific metabolic shift towards increased malonyl-CoA and decreased acetyl-CoA upon feeding, suggesting altered energy substrate utilization.
• The findings highlight the intricate tissue-specific regulation of CoA metabolism in response to nutritional cues.