Untargeted Metabolomics and Chemometrics Elucidate Dynamic Plasma Profile Changes Induced by Cocoa Shell in Female Rats.

Abstract

Objective: This study aimed to explore the effects of cocoa shell extract (CSE) supplementation on the plasma metabolome of female rats.

Methods: Female rats were supplemented with CSE (250 mg/kg/day) over seven days, and plasma samples were collected at baseline, day 4, and day 7 for untargeted metabolomic profiling using LC-ESI-QTOF.

Results: A total of 244 plasma metabolites were identified, while 180 were detected in the CSE. Among these, only 21 compounds were consistently detected in both the CSE and the plasma at baseline and day 7. Notably, just three compounds, caffeine, theobromine, and N-isovaleroylglycine, were bioavailable, detected only in plasma after supplementation on day 7, confirming their absorption and systemic distribution. Pathways related to caffeine metabolism, glycerophospholipid biosynthesis, nicotinate, and nicotinamide metabolism were significantly upregulated, indicating enhanced lipid metabolism and energy homeostasis. Conversely, reductions were observed in pathways involving tryptophan, glutathione, arginine, and proline, pointing to shifts in amino acid metabolism and antioxidant defense mechanisms. Network analysis revealed significant changes in the cholinergic synapse, retrograde endocannabinoid signaling, and glutamatergic synapse pathways, which are crucial for cellular communication and neurotransmission.

Conclusions: The observed metabolic reconfiguration demonstrates CSE's rapid modulation of the metabolome, highlighting the bioavailability of its key components. These findings suggest potential mechanisms for CSE as a functional food ingredient with health-promoting effects, potentially supporting cognitive function and metabolic health through energy metabolism, neurotransmission, and lipid signaling pathways.