Table 2.

In vivo and in vitro effects of melatonin on m⁶A modifications by methyltransferases, demethylases, and “readers”.

m6A Modification Enzymes	Model/Description	Melatonin Doses	Melatonin’s Effects	Reference
METTL3/METT14	Epididymal WAT/Alimentary obesity mouse model	20 mg/kg IP injection × 14 days	Reduced transcription.	[861]
ALKBH5	Epididymal WAT/Alimentary obesity mouse model	20 mg/kg IP injection × 14 days	Reduced transcription.	[861]
FTO/YTHDF2	Epididymal WAT/Alimentary obesity mouse model	20 mg/kg IP injection × 14 days	Significantly increased transcriptions.	[861]
METTL3	MSC-derived EV/SCI mouse model	1 μmol/L for 48 h.	Reduced transcription	[862]
METTL3	Long-term cultured ESCs	10 μM × 90 days.	Maintained pluripotency of ESCs by significantly reducing METTL3 levels.	[863]
METTL3	Mouse SSC Cr (VI)-induced m6A downregulation	50 μM pretreatment	Restored METTL3 levels, attenuated m6A modification reduction.	[872]

WAT: white adipose tissue; MSC: mesenchymal stem cell; EV: extracellular vesicle; SCI: spinal cord injury; ESCs: embryonic stem cells; SSC: spermatogonial stem cell; Cr (VI): chromium (VI); (see Abbreviations for additional acronyms).