3-Methylhistidine (3-MH) is a post-translationally modified amino acid which is excreted in human urine.[1][2] Urinary concentration of 3-methylhistidine is a biomarker for skeletal muscle protein breakdown in humans who have been subject to muscle injury.[1][3][4] Urinary 3-methylhistidine concentrations are also elevated from consumption of soy-based products and meat, particularly chicken.[1]

Biochemistry

3-Methylhistidine is a metabolic product that is produced in the body via the enzymatic methylation of histidine during peptide bond synthesis and the methylation of actin and myosin.[1][2]

Detection in body fluids

The normal concentration of 3-methylhistidine in the urine of healthy adult humans has been detected and quantified in a range of 3.63–69.27 micromoles per millimole (μmol/mmol) of creatinine, with most studies reporting the average urinary concentration between 15–20 μmol/mmol of creatinine.[1] The average concentration of 3-methylhistidine in human blood plasma has been detected and quantified at 2.85 micromolar (μM) with a range of 0.0–5.9 μM.[1] The average concentration of 3-methylhistidine in human cerebrospinal fluid (CSF) has been detected and quantified at 3.82 μM with a range of 1.39–6.25 μM.[1]

References

  1. ^ a b c d e f g h "3-Methylhistidine". HMDB Version 4.0. Human Metabolome Database. 20 December 2017. Retrieved 25 December 2017.
  2. ^ a b c "3-Methyl-L-histidine". PubChem Compound. United States National Library of Medicine – National Center for Biotechnology Information. 23 December 2017. Retrieved 25 December 2017.
  3. ^ Chinkes DL (September 2005). "Methods for measuring tissue protein breakdown rate in vivo". Current Opinion in Clinical Nutrition and Metabolic Care. 8 (5): 534–537. doi:10.1097/01.mco.0000170754.25372.37. PMID 16079625. S2CID 8318490.
  4. ^ Holm L, Kjaer M (September 2010). "Measuring protein breakdown rate in individual proteins in vivo". Current Opinion in Clinical Nutrition and Metabolic Care. 13 (5): 526–531. doi:10.1097/MCO.0b013e32833c3c64. PMC 3008417. PMID 20616712.