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March 14, 2022
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Agmatine, aka 1-(4-aminobutyl)guanidine, is a natural substance that is formed by the decarboxylation of the amino acid l-arginine, the Molecule of the Week for September 25, 2017. Agmatine belongs to a group of molecules called biogenic amines (BAs), which includes former MOTWs histamine, tyramine, putrescine, cadaverine, spermidine, and spermine. Agmatine and other BAs are particularly abundant in high-protein foods such as meats and dairy products.

In 1910, biochemist Albrecht Kossel at the Heidelberg Academy of Sciences (Germany) discovered agmatine in herring roe and reported a synthesis of it. Kossel was awarded the Nobel Prize in Physiology or Medicine the same year for his discoveries in cell biology. Nine years later, in an extensive study, Frederick W. Heyl at Upjohn (Kalamazoo, MI) reported the presence of agmatine in pollen protein extracts from ragweed (Ambrosia artemisiifolia).

Agmatine has a variety of biochemical properties. It can modify neurotransmitter systems, ion channels, nitric oxide (NO) synthesis, and polyamine metabolism. In a 1994 article, G. Li and co-workers at Cornell University Medical College (New York City) reported that agmatine is formed in the bovine brain and displaces clonidine by binding to α-2-adrenergic and imidazoline receptors. They also state that agmatine may act as a neurotransmitter.

Agmatine is is described as an important biomolecule in the 2021 book Starving Cancer Cells: Evidence-Based Strategies to Slow Cancer Progression by Robert Fried, Richard M. Carlton, and Dennis A. Fried. They cite a study in which agmatine abolished ornithine decarboxylase protein expression and polyamines biosynthesis to induce caspase-dependent apoptosis, and another that showed that it inhibited NO production mainly by depressing inducible NO synthase activity.

Agmatine hazard information

Hazard class*GHS code and hazard statement
Acute toxicity, oral, category 4H302—Harmful if swallowedChemical Safety Warning
Skin corrosion/irritation, category 2H315—Causes skin irritationChemical Safety Warning

Serious eye damage/eye irritation, category 2A

H319—Causes serious eye irritationChemical Safety Warning
Acute toxicity, inhalation, category 4H332—Harmful if inhaledChemical Safety Warning
Specific target organ toxicity, single exposure, respiratory tract irritation, category 3H335—May cause respiratory irritationChemical Safety Warning

*Globally Harmonized System (GHS) of Classification and Labeling of Chemicals. Explanation of pictograms.

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Agmatine fast facts

CAS Reg. No.306-60-5
Guanidine, N-(4-aminobutyl)-
Empirical formulaC5H14N4
Molar mass130.19 g/mol
AppearanceWhite crystals or powder
Melting point102 °C
Water solubility≈13 g/L

MOTW update

Imidacloprid1 was the Molecule of the Week for August 25, 2014. It is a neonicotinoid pesticide that has come under regulatory pressure because of its neurotoxic risk to honeybees.

In 2020, the US Environmental Protection Agency unexpectedly announced that it was allowing the continued use of neonicotinoids, including imidacloprid. But the pressure to restrict them continues. Last month, the California Department of Pesticide Regulations (DPR) announced it will ban the use of neonicotinoids on flowering crops when they are in bloom. DPR estimates that this will reduce neonicotinoid use by ≈45% in California.

1. CAS Reg. No. 138261-41-3.

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