Urumin is a

naturally occurring A natural product is a natural compound or substance produced by a living organism—that is, found in nature. In the broadest sense, natural products include any substance produced by life. Natural products can also be prepared by chemical sy ...

27-

amino acid Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha a ...

virucidal host defense peptide against the human influenza A virus. It was discovered and isolated from the skin of ''

Hydrophylax bahuvistara ''Hydrophylax bahuvistara'', commonly known as the widespread fungoid frog, is a colourful frog found widespread in peninsular India, distributed in Maharashtra, Karnataka, Goa and Madhya Pradesh. It is very similar to another species with ...

'', a species of

frog A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-frog" ''Triadobatrachus'' is ...

found in

South India South India, also known as Dakshina Bharata or Peninsular India, consists of the peninsular southern part of India. It encompasses the Indian states of Andhra Pradesh, Karnataka, Kerala, Tamil Nadu, and Telangana, as well as the union territ ...

, by a team of Emory University researchers. The team that discovered urumin tested the peptide against 8 different H1N1 and 4 different H3N2 viruses, as well as various other influenza viruses. The peptide specifically targets the evolutionarily conserved H1 hemagglutinin stalk region of H1-containing influenza A viruses. Additionally, urumin was active against drug-resistant influenza A viruses, that were resistant against

oseltamivir Oseltamivir, sold under the brand name Tamiflu, is an antiviral medication used to treat and prevent influenza A and influenza B, viruses that cause the flu. Many medical organizations recommend it in people who have complications or are at high ...

zanamivir Zanamivir is a medication used to treat and prevent influenza caused by influenza A and influenza B viruses. It is a neuraminidase inhibitor and was developed by the Australian biotech firm Biota Holdings. It was licensed to Glaxo in 1990 and ap ...

and

peramivir Peramivir (trade name Rapivab) is an antiviral drug developed by BioCryst Pharmaceuticals for the treatment of influenza. Peramivir is a neuraminidase inhibitor, acting as a transition-state analogue inhibitor of influenza neuraminidase and th ...

. While its

mechanism of action In pharmacology, the term mechanism of action (MOA) refers to the specific biochemical interaction through which a drug substance produces its pharmacological effect. A mechanism of action usually includes mention of the specific molecular targ ...

is not fully understood, urumin seems to inhibit viral growth by physically destroying influenza A

virion A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's ...

s, and is able to protect naive mice from doses of influenza A

infection An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable dis ...

as high as 2 times the

LD50 In toxicology, the median lethal dose, LD50 (abbreviation for "lethal dose, 50%"), LC50 (lethal concentration, 50%) or LCt50 is a toxic unit that measures the lethal dose of a toxin, radiation, or pathogen. The value of LD50 for a substance is the ...

. Because of its specific targeting of the hemagglutinin stalk region of the influenza A virus, the mechanism of action of urumin is similar to that of antibodies induced in the body by universal influenza vaccines. Urumin was also tested for toxicity against erythrocytes and showed a

TD50 In toxicology, the median toxic dose (TD50) of a drug or toxin is the dose at which toxicity occurs in 50% of cases. The ''type'' of toxicity should be specified for this value to have meaning for practical purposes. The median toxic dose encompasse ...

of 2,450 μM and TI of 664.7, indicating a favorable toxicity profile against erythrocytes. As such, urumin may represent the basis for a potential first-line antiviral treatment against influenza A, particularly in the context of influenza outbreaks, although the discoverers of the peptide have stated that urumin is far from becoming an anti-flu drug. Urumin was named after

Urumi Urumi (Malayalam: ''uṟumi''; Sinhalese: ''ethunu kaduwa''; Hindi: ''āra'') is a sword with a flexible, whip-like blade, originating in modern-day Kerala in the Indian subcontinent. It is thought to have existed from as early as the Sangam per ...

, a sword used in Kalaripayattu, the martial art of

Kerala Kerala ( ; ) is a state on the Malabar Coast of India. It was formed on 1 November 1956, following the passage of the States Reorganisation Act, by combining Malayalam-speaking regions of the erstwhile regions of Cochin, Malabar, South ...

, where it was discovered.

References

Anti-influenza agents Peptides Virucides {{antimicrobial-stub