Melatonin Deficits Result in Pathologic Metabolic Reprogramming in Differentiated Neurons

Area of Science:

• Neuroscience
• Cell Biology
• Metabolism

Background:

• Mature neurons rely on oxidative phosphorylation (OXPHOS) for ATP, a process generating reactive oxygen species.
• Melatonin, produced in neuronal mitochondria, scavenges free radicals and inhibits cell death pathways.
• Previous work linked melatonin loss to mitochondrial DNA release and inflammation.

Purpose of the Study:

• To investigate the role of melatonin in metabolic reprogramming during neuronal differentiation.
• To determine if melatonin deficiency impacts the switch to OXPHOS in mature neurons.
• To assess the effect of melatonin supplementation on neuronal metabolic defects.

Main Methods:

• Comparison of metabolic profiles in aralkylamine N-acetyltransferase knockout (AANAT-KO) neurons versus AANAT-expressing neurons.
• Analysis of BAK and BAX protein levels in mature neurons.
• Assessment of metabolic reprogramming and BAK/BAX levels following exogenous melatonin treatment during differentiation.

Main Results:

• Melatonin deficiency specifically altered metabolic reprogramming in mature neurons, not neural progenitors.
• AANAT-KO neurons exhibited elevated levels of pro-apoptotic proteins BAK and BAX.
• Exogenous melatonin treatment rescued metabolic defects and normalized BAK/BAX levels in differentiating AANAT-KO neurons.

Conclusions:

• Melatonin is crucial for proper metabolic reprogramming during the neuronal maturation switch to OXPHOS.
• Melatonin deficiency compromises neuronal health by disrupting energy metabolism and increasing cell death markers.
• Melatonin supplementation can restore normal metabolic function and cellular homeostasis in developing neurons.