Homocysteine, an amino acid synthesized intracellularly by removal of the N-methyl group from the essential amino acid methionine. High plasma level of homocysteine is called hyperhomocysteinemia is a clinical biomarker for increased risk of cardiovascular disease, thromboembolic diseases, and myocardial infarction. It was shown, that hyperhomocysteinemia could be an independent risk factor for dementia and Alzheimer's disease. The falling of homocysteine concentrations in response to increasing B-group-vitamin status, have the hope that mental decline, or Alzheimer's disease, could be prevented by dietary modification or food fortification. Besides, homocysteine can behave as an anti-oxidant agent by increasing the antioxidant capacity of the tumor and endothelial cells.

Eltanolone (pregnanolone) is an endogenous neuro active steroid that is biosynthesized from progesterone. It is a positive allosteric modulator of the GABAA receptor, as well as a negative allosteric modulator of the glycine receptor. There is strong evidence that it is involved in the pathophysiology of premenstrual syndrome, catamenial epilepsy, major depression, and stress-sensitive brain disorders and is known to have sedative, anxiolytic, anesthetic, and anticonvulsant effects. It was investigated for clinical use as a general (intravenous) anesthetic. It produced unwanted side effects such as convulsions on occasion, and for that reason was not marketed. Pregnanolone possesses neuroprotective and neurotrophic properties thus has been through a number of clinical trials including for treatment of traumatic brain injury (TBI), Alzheimer disease, cognitive impairment and fragile X-associated tremor/ataxia syndrome.

Androsterone, a neurosteroid, acts as a positive allosteric modulator of GABA(A) receptors, that can cross into the brain and could have effects on brain function. It was discovered, that the association of beta subunits with alpha subunits GABA(A) receptor affects the sensitivity of glycine receptors to androsterone. In spite of that, androsteron is considered as an inactive metabolite of testosterone. In addition, was studied that androsterone possessed anticonvulsant properties. Although of low potency, the androsterone was present in high abundance and was able to represent endogenous modulator of seizure susceptibility.

PGD2 (Prostaglandin D2) is a major cellular regulator, has been shown to bind different receptors: D prostanoid receptor (DP) and chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2). PGD2 reportedly inhibits platelet aggregation, the proliferation of cells, and activation of neutrophils. This compound is also a potent vasodilator that also relaxes smooth muscle but causes contraction of the bronchial airways. PGD2 promotes T cell migration via CRTH2 and aggravates asthma. In contrast, there have been some studies suggesting that PGD2 exerts anti-inflammatory effects via DP, such as inhibiting the migration and activation of neutrophils, basophils, dendritic cells and T cells. Elevated levels of prostaglandin D2 (PGD2) have been shown to be present in the bald scalp of androgenic alopecia (AGA) patients and was suggested the PGD(2)-GPR44 pathway as a potential target for treatment. Also was revealed, that PGD2 might be a new target for asthma therapy, PGD2 in serum and BALF were lower in the treated group than in the untreated group.

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.

3-Methoxytyramine (3-MT) is a human trace amine that occurs as a metabolite of the neurotransmitter dopamine. It has been shown to act as an agonist of human TAAR1, and an inhibitor of mitochondrial respiration. 3-MT has garnered research interest for its potential links and implications to Parkinson's disease and other Neurological disorders.