Tyramine is a naturally occurring monoamine compound and trace amine derived from the amino acid tyrosine. Tyramine occurs widely in plants and animals, and is metabolized by the enzyme monoamine oxidase. Tyramine is an alpha-adrenergic agonist. Hypertension can occur, from ingestion of tyramine-rich foods in conjunction with monoamine oxidase inhibitors. The possibility that tyramine acts directly as a neurotransmitter was revealed by the discovery of a G protein-coupled receptor with high affinity for tyramine, called TAAR. It exhibits sympathomimetic effects by causing the release of endogenic norepinephrine. It has been used in mydriatic eyedrops. This has been said to reduce the intraocular pressure in rabbits and in some patients with open-angle glaucoma.

Hyodeoxycholic acid, also known as HDCA, is a secondary bile acid. Natural 6alpha-hydroxylated bile acids are receptor-specific activators of nuclear liver X receptor alpha (LXRalpha), a nuclear receptor regulating the expression of the cholesterol 7alpha-hydroxylase gene. AHRO-001 (Hyodeoxycholic acid) is in phase I clinical trials for the treatment of atherosclerosis. Through a complex signaling processes utilizing LXR receptors, the compound is designed to increase the efficiency of cholesterol efflux using the HDL cells, which act on all cholesterol in the arterial circulation as well as in the lipid core of plaque deposits in the artery walls. Use of AHRO-001 has shown no adverse effects on morbidity, mortality or toxicity and has been well tolerated at high doses.

Cytidine is a substrate of the uridine-cytidine kinase and is a part nucleic acids. It can serve as a substrate for the salvage pathway of pyrimidine nucleotide synthesis, as a precursor of the cytidine triphosphate (CTP) needed in the phosphatidylcholine (PC) and phosphatidylethanolamine (PE) biosynthetic pathway. Cytidine was also used under the brand name posilent in Germany for the treatment of muscular, accommodative, and nervous eye disorders.

Phenylacetate is the ester of a phenol and acetic acid. It is a metabolite of anticancer drug phenylbutyrate (PB), natural neurotransmitter phenylethylamine. Naturally, it is an odorant found in strawberries, passion fruit, and black tea. Phenylacetate level in urine was used as a marker for the diagnosis of some forms of unipolar major depressive disorders. Phenylacetate is used as a tool substrate to study esterase activity in the blood of patients in clinical studies of the effect of nutritional supplements on paraoxonase-1 levels.

11-Deoxycortisol (also known as cortodoxone) is the predominant deoxycorticosteroid and is the immediate precursor of cortisol, which is formed by the enzymatic action of 11beta-hydrozylase (P450). Deficiency of this enzyme causes congenital adrenal hyperplasia, which is characterized by hypertension. 11-deoxycortisol is measured as part of the Metyrapone Test. Metyrapone blocks the formation of cortisol, resulting in increased secretion of Adrenocorticotropic hormone (ACTH) and 11-deoxycortisol in normal individuals.