Galactosamine is a hexosamine derived from galactose with the molecular formula C6H13NO5. A few amino sugars, including galactosamine, have been shown to kill tumors in the laboratory. It is unlikely to be used in cancer therapy, however. D-galactosamine is a hepatotoxic, or liver-damaging, agent. Researchers studying animal models of liver failure sometimes use D-galactosamine to induce liver damage. Galactosamine is also helpful for researchers studying agents that might protect the liver from damage.

Kynurenine is a metabolite of the amino acid L-tryptophan used in the production of niacin. Kynurenine is synthesized by the enzyme tryptophan dioxygenase, which is made primarily but not exclusively in the liver, and indoleamine 2,3-dioxygenase, which is made in many tissues in response to immune activation. Kynurenine and its further breakdown products carry out diverse biological functions, including dilating blood vessels during inflammation and regulating the immune response. Evidence suggests that increased kynurenine production may precipitate depressive symptoms associated with interferon treatment for hepatitis C. Cognitive deficits in schizophrenia are associated with imbalances in the enzymes that break down kynurenine. Kynurenine production is increased in Alzheimer's disease and cardiovascular disease where its metabolites are associated with cognitive deficits and depressive symptoms.

Corticosterone is an adrenocortical steroid, the major glucocorticoid that has modest but significant activities as a mineralocorticoid and a glucocorticoid. Corticosterone is of minor importance in humans but is known, that it has a profound effect on the structure and function of the hippocampus. Brain corticosterone may involve memory storage and emotional stress might cause increases in plasma corticosterone.