The function of ALDH7A1 (aldehyde dehydrogenase 7 family member A1, Ensembl gene identifier ENSG00000164904) is as follows. Aldehyde dehydrogenase enzyme that mediates important protective effects (PubMed:16491085, PubMed:20207735, PubMed:20554659, PubMed:21338592, PubMed:25554827, PubMed:31302938, PubMed:31652343, PubMed:38604394, PubMed:40233740). Protects cells from oxidative stress by metabolizing a number of lipid peroxidation-derived aldehydes (PubMed:16491085, PubMed:20207735, PubMed:21338592, PubMed:40233740). Involved in cellular defense against hyperosmotic stress by metabolizing betaine aldehyde to betaine, an important cellular osmolyte and methyl donor (PubMed:20207735). {ECO:0000269|PubMed:16491085, ECO:0000269|PubMed:20207735, ECO:0000269|PubMed:20554659, ECO:0000269|PubMed:21338592, ECO:0000269|PubMed:25554827, ECO:0000269|PubMed:31302938, ECO:0000269|PubMed:31652343, ECO:0000269|PubMed:38604394, ECO:0000269|PubMed:40233740}. [Isoform 1]: Involved in lysine catabolism in the brain by mediating the conversion of L-aminoadipate-semialdehyde ((S)-2-amino-6- oxohexanoate) to L-2-aminoadipate. {ECO:0000269|PubMed:16491085, ECO:0000269|PubMed:20207735}. [Isoform 2]: Acts as a key inhibitor of ferroptosis both by generating membrane NADH and decreasing the level of reactive aldehydes (PubMed:40233740). Recruited to plasma membrane in response to ferroptotic stress and phosphorylation by AMPK, generating membrane NADH to support AIFM2/FSP1 activity, an essential ferroptosis suppressor protein (PubMed:40233740). Also directly inhibits ferroptosis by decreasing lipid peroxidation via consumption of reactive aldehydes, such as 4-hydroxynonenal (4-HNE) and malonaldehyde (PubMed:40233740). Also acts as a regulator of cellular energy homeostasis in response to cellular energy stress, such as starvation and hypoxia, by inhibiting COPI-mediated intracellular transport, thereby reducing cellular energy consumption (PubMed:31492851). .