3-Hydroxyphenylacetic acid and 4-hydroxyphenylacetic acid are produced by the bacterial fermentation of amino acids, much like Indoleacetic acid (IAA).

4-hydroxyphenyllactate is present in relatively higher concentrations in the cerebrospinal fluid and urine of patients with phenylketonuria (PKU) and tyrosinemia.

4-hydroxyphenyllactate is present in relatively higher concentrations in the cerebrospinal fluid and urine of patients with phenylketonuria (PKU) and tyrosinemia.

AKA: 4-Hydroxyphenylpyruvate, 4-HPPA

4-hydroxyphenylpyruvic acid is an intermediate in the breakdown of phenylalanine.

4-hydroxyphenylpyruvic acid is converted to homogentisate; a blockage at this step results in increased homogentisate, which can be diagnostic of alkaptonuria.

If the pathway is not blocked, 4-HPPA ends up in the Krebs cycle converted into fumaric acid.

AKA: 4-Hydroxyphenylpyruvate, 4-HPPA

4-hydroxyphenylpyruvic acid is an intermediate in the breakdown of phenylalanine.

4-hydroxyphenylpyruvic acid is converted to homogentisate; a blockage at this step results in increased homogentisate, which can be diagnostic of alkaptonuria.

If the pathway is not blocked, 4-HPPA ends up in the Krebs cycle converted into fumaric acid.

4-M-E2 (4-Methoxyestradiol) and 4-OH-E2 (4-Hydroxyestradiol) are two important estrogen metabolites whose levels are of particular interest in post-menopausal women, especially when assessed through a Hormone and Urinary Metabolites Assessment Profile. This profile is designed to evaluate the balance and metabolism of hormones, providing valuable insights into a woman's health status after menopause.

Healthy Phase II metabolism methylates 2-hydroxy (2-OH) estrogens to the more cancer-protective 2-methoxy (2-MeO) forms, and neutralizes the potentially carcinogenic 4-OH estrogens to their 4-MeO forms.

Healthy Phase II metabolism methylates 2-hydroxy (2-OH) estrogens to the more cancer-protective 2-methoxy (2-MeO) forms, and neutralizes the potentially carcinogenic 4-OH estrogens to their 4-MeO forms.

Healthy Phase II metabolism methylates 2-hydroxy (2-OH) estrogens to the more cancer-protective 2-methoxy (2-MeO) forms, and neutralizes the potentially carcinogenic 4-OH estrogens to their 4-MeO forms.

4-Methoxyestradiol (4-ME2) is an endogenous, naturally occurring methoxylated catechol estrogen and metabolite of estradiol that is formed by catechol O-methyltransferase via the intermediate 4-hydroxyestradiol.

Neutralized version of carcinogenic 4-OH-E1

Methyl metabolites are considered inactive and are correlated with antiproliferative effects. Proper elimination of 4-M-E2 requires optimal excretion via GI tract optimization. To fully understand this value, it may be beneficial to examine the 4-M-E2 / 4-OH-E2 ratio.