Avenanthramide
Encyclopedia
Avenanthramides are a type of oat
phytoalexin
s that exist predominantly in the groats
of oat seeds.
Among a group of at least 25 avenanthramides that differ in the substituents on the cinnamic acid
and anthranilic acid
rings, three are predominant in oat grain: Bc (also called avenanthramide C), Bf (also called avenanthramide B) and Bp (also called avenanthramide A).
In vitro
experiments indicate they have significant antioxidant
activities, with Bc > Bf > Bp. In human and animal tests, this antioxidant capacity provides health benefits ranging from reduced rate of LDL oxidation to protecting against cancers and heart disease
. Because of its antioxidant properties, high levels of avenanthramide are desirable in oat grain. Researchers at the Agricultural Research Service
(ARS) currently are trying to understand what environmental factors regulate the amount of avenanthramide produced in oat grain. http://www.ars.usda.gov/is/pr/2010/100201.htm Past studies have found an increase in avenanthramide production in plants that are infected by a fungus, leading researchers to believe that avenanthramide is used as a chemical defense in helping the oat grain fight off the fungus. ARS researchers found that cultivars with the strongest resistance to crown rust, a fungus that affects oat grains, had the highest concentration of avenanthramide. However, because not all cultivars with high crown rust resistance had high levels of avenanthramide, researchers suspect other environmental factors play a role in avenanthramide production. Nevertheless, scientists suggest farmers can still select for highly resistant cultivars to increase the production of avenanthramide in their grain.
They are tranilast
analogues and have anti-inflammatory and antifibrotic properties, probably due to TGF-beta inhibitory effects.
and antipruritic
properties of oatmeal
. In 1978 the U.S. Food and Drug Administration
(FDA) external review panel noted that colloidal oatmeal was safe and effective for the symptomatic relief of dry skin and itching.
Recent studies were conducted to verify whether avenanthramides are also responsible for the antipruritic activity of oat extracts. The results of human in vivo skin prick tests combined with an in vitro model, investigating the inhibitory activity of avenanthramides on the histamine
net release from rat peritoneal mast cells stimulated by substance P
showed a clear indication that avenanthramides found in oat extract play a major role in the reduction of itching and redness in skin. Because of the fundamental role of histamine in itch sensation, our results can be considered as a clear indication that oat extracts with a standardized content of avenanthramides are useful materials to reduce histamine related itch sensation and redness in skin.
Most recently, extracts containing avenanthramides have been used in veterinary medicine
in various topical forms, such as shampoos, sprays and ear cleansing solutions, by AvenaPro Pet Solutions for the relief of companion animals exhibiting adverse skin conditions, including atopic dermatitis
.
OATS
OATS - Open Source Assistive Technology Software - is a source code repository or "forge" for assistive technology software. It was launched in 2006 with the goal to provide a one-stop “shop” for end users, clinicians and open-source developers to promote and develop open source assistive...
phytoalexin
Phytoalexin
Phytoalexins are antimicrobial substances synthesized de novo by plants that accumulate rapidly at areas of incompatible pathogen infection. They are broad spectrum inhibitors and are chemically diverse with different types characteristic of particular plant species...
s that exist predominantly in the groats
Groats
Groats are the hulled grains of various cereals, such as oats, wheat, barley or buckwheat . Groats are whole grains that include the cereal germ and fiber-rich bran portion of the grain as well as the endosperm...
of oat seeds.
Among a group of at least 25 avenanthramides that differ in the substituents on the cinnamic acid
Cinnamic acid
Cinnamic acid is a white crystalline organic acid, which is slightly soluble in water.It is obtained from oil of cinnamon, or from balsams such as storax. It is also found in shea butter and is the best indication of its environmental history and post-extraction conditions...
and anthranilic acid
Anthranilic acid
Anthranilic acid is the organic compound with the formula C6H4COOH. This amino acid is a white solid when pure, although commercial samples may appear yellow. The molecule consists of a benzene ring with two adjacent functional groups, a carboxylic acid and an amine...
rings, three are predominant in oat grain: Bc (also called avenanthramide C), Bf (also called avenanthramide B) and Bp (also called avenanthramide A).
In vitro
In vitro
In vitro refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments...
experiments indicate they have significant antioxidant
Antioxidant
An antioxidant is a molecule capable of inhibiting the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons or hydrogen from a substance to an oxidizing agent. Oxidation reactions can produce free radicals. In turn, these radicals can start chain reactions. When...
activities, with Bc > Bf > Bp. In human and animal tests, this antioxidant capacity provides health benefits ranging from reduced rate of LDL oxidation to protecting against cancers and heart disease
Heart disease
Heart disease, cardiac disease or cardiopathy is an umbrella term for a variety of diseases affecting the heart. , it is the leading cause of death in the United States, England, Canada and Wales, accounting for 25.4% of the total deaths in the United States.-Types:-Coronary heart disease:Coronary...
. Because of its antioxidant properties, high levels of avenanthramide are desirable in oat grain. Researchers at the Agricultural Research Service
Agricultural Research Service
The Agricultural Research Service is the principal in-house research agency of the United States Department of Agriculture . ARS is one of four agencies in USDA's Research, Education and Economics mission area...
(ARS) currently are trying to understand what environmental factors regulate the amount of avenanthramide produced in oat grain. http://www.ars.usda.gov/is/pr/2010/100201.htm Past studies have found an increase in avenanthramide production in plants that are infected by a fungus, leading researchers to believe that avenanthramide is used as a chemical defense in helping the oat grain fight off the fungus. ARS researchers found that cultivars with the strongest resistance to crown rust, a fungus that affects oat grains, had the highest concentration of avenanthramide. However, because not all cultivars with high crown rust resistance had high levels of avenanthramide, researchers suspect other environmental factors play a role in avenanthramide production. Nevertheless, scientists suggest farmers can still select for highly resistant cultivars to increase the production of avenanthramide in their grain.
They are tranilast
Tranilast
Tranilast is an antiallergic drug. It was developed by Kissei Pharmaceuticals and was approved in 1982 for use in Japan and South Korea for bronchial asthma...
analogues and have anti-inflammatory and antifibrotic properties, probably due to TGF-beta inhibitory effects.
Anti-inflammatory and anti-itch properties
Ancient literature describes the anti-inflammatoryAnti-inflammatory
Anti-inflammatory refers to the property of a substance or treatment that reduces inflammation. Anti-inflammatory drugs make up about half of analgesics, remedying pain by reducing inflammation as opposed to opioids, which affect the central nervous system....
and antipruritic
Antipruritic
Antipruritics, also known as anti-itch drugs, are medications that inhibit the itching that is often associated with sunburns, allergic reactions, eczema, psoriasis, chickenpox, fungal infections, insect bites and stings like those from mosquitoes, fleas, and mites, and contact dermatitis and...
properties of oatmeal
Oatmeal
Oatmeal is ground oat groats , or a porridge made from oats . Oatmeal can also be ground oat, steel-cut oats, crushed oats, or rolled oats....
. In 1978 the U.S. Food and Drug Administration
Food and Drug Administration
The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
(FDA) external review panel noted that colloidal oatmeal was safe and effective for the symptomatic relief of dry skin and itching.
Recent studies were conducted to verify whether avenanthramides are also responsible for the antipruritic activity of oat extracts. The results of human in vivo skin prick tests combined with an in vitro model, investigating the inhibitory activity of avenanthramides on the histamine
Histamine
Histamine is an organic nitrogen compound involved in local immune responses as well as regulating physiological function in the gut and acting as a neurotransmitter. Histamine triggers the inflammatory response. As part of an immune response to foreign pathogens, histamine is produced by...
net release from rat peritoneal mast cells stimulated by substance P
Substance P
In the field of neuroscience, substance P is a neuropeptide: an undecapeptide that functions as a neurotransmitter and as a neuromodulator. It belongs to the tachykinin neuropeptide family. Substance P and its closely related neuropeptide neurokinin A are produced from a polyprotein precursor...
showed a clear indication that avenanthramides found in oat extract play a major role in the reduction of itching and redness in skin. Because of the fundamental role of histamine in itch sensation, our results can be considered as a clear indication that oat extracts with a standardized content of avenanthramides are useful materials to reduce histamine related itch sensation and redness in skin.
Most recently, extracts containing avenanthramides have been used in veterinary medicine
Veterinary medicine
Veterinary Medicine is the branch of science that deals with the prevention, diagnosis and treatment of disease, disorder and injury in non-human animals...
in various topical forms, such as shampoos, sprays and ear cleansing solutions, by AvenaPro Pet Solutions for the relief of companion animals exhibiting adverse skin conditions, including atopic dermatitis
Atopic dermatitis
Atopic dermatitis is an inflammatory, chronically relapsing, non-contagious and pruritic skin disorder...
.