Table 1. Possible theranostic applications and their effects within the polyamine metabolism.

Target gene	Manipulation/ agent	Mechanism	Effect	References
ODC	DFMO	Irreversible ODC inhibition	Neuroprotective	[8]
SSAT	KO mouse	Deletion of SSAT	Neuroprotective	[155]
PAO	MDL 72527	Irreversible PAO inhibition	Neuroprotective	[180, 181]
SMO	Transgenic mouse	SMO overexpression	Neurotoxic	[182]
Arg1, Arg2	Norvaline	Noncompetitive arginase inhibition	Neuroprotective	[11, 167–169]
Arg1, Arg2	Resveratrol	Noncompetitive arginase inhibition	Neuroprotective	[183]
Arg1, Arg2	Chloroquine	Competitive arginase inhibition	Neuroprotective	[184]
Arg1, Arg2	Citrulline	Noncompetitive arginase inhibition	Neuroprotective	[172, 185]
Arg2	KO mouse	Deletion of Arg2	Neuroprotective	[186]
Arg1	AAV-mediated overexpression	Arg1 overexpression in the hippocampus	Neuroprotective	[173]
Arg1 in myeloid cells	Transgenic mouse	Arg1 haploinsufficiency	Neurotoxic	[174]