Arginine is found in all protein foods and is very abundant in seeds and nuts. It is considered a semi-essential amino acid during early development, infection/inflammation, or renal and/or intestinal impairment. It has many functions in the body including:

- ammonia disposal in the urea cycle

- immune function

- stimulation of insulin release

- muscle metabolism (creatine/creatinine precursor)

- nitric oxide (NO) formation

- glutamic acid and proline formation

- glucose/glycogen conversion

- stimulation of the release of growth hormone, vasopressin, and prolactin

- wound healing

Because arginine is a precursor for nitric oxide synthesis, it is often used therapeutically in cardiovascular disease for its vasodilatory effects.

Arginine is found in all protein foods and is very abundant in seeds and nuts. It is considered a semi-essential amino acid during early development, infection/inflammation, or renal and/or intestinal impairment.

Arginine is a conditionally essential amino acid that is critical for your cardiovascular health and detoxification functions. The amino acid, arginine, is used to make the powerful blood vessel regulator, nitric oxide. Nitric oxide acts to lower blood pressure.

Physiological Function:

L-Arginine is a conditionally essential amino acid found in the diet. It is a dietary supplement used mostly by athletes because it is the amino acid that directly produces nitric oxide via the nitric oxide synthase enzymes.

Arginine helps heal injuries, aids kidneys in removing waste, and boosts immune system function.

Arginine is a conditionally essential amino acid that is critical for your cardiovascular health and detoxification functions. The amino acid, arginine, is used to make the powerful blood vessel regulator, nitric oxide. Nitric oxide acts to lower blood pressure.

Argininosuccinate (aka Arginosuccinic acid) is a basic amino acid. Some cells synthesize it from citrulline, aspartic acid and use it as a precursor for arginine in the urea cycle or Citrulline-NO cycle. The enzyme that catalyzes the reaction is argininosuccinate synthetase. Argininosuccinic acid is a precursor to fumarate in the citric acid cycle via argininosuccinate lyase. Defects in the argininosuccinate lyase enzyme can lead to argininosuccinate lyase deficiency, which is an inborn error of metabolism.

Argininosuccinate (aka Arginosuccinic acid) is a basic amino acid. Some cells synthesize it from citrulline, aspartic acid and use it as a precursor for arginine in the urea cycle or Citrulline-NO cycle. The enzyme that catalyzes the reaction is argininosuccinate synthetase. Argininosuccinic acid is a precursor to fumarate in the citric acid cycle via argininosuccinate lyase. Defects in the argininosuccinate lyase enzyme can lead to argininosuccinate lyase deficiency, which is an inborn error of metabolism.

It is not normally detectable in healthy adults. Adult argininosuccinate lyase insufficiencies are typically treated with a lower protein/higher carbohydrate diet, arginine supplementation, and avoidance of fasting.

Aromatic L-amino acid decarboxylase (AADC) enzyme plays a crucial role in the human body's ability to process certain amino acids into neurotransmitters, which are chemical messengers that transmit signals in the brain and other areas of the nervous system.

AADC acts on L-amino acids, particularly those with an aromatic side chain, such as L-dopa (levodopa), converting them into dopamine, and 5-hydroxytryptophan into serotonin. These neurotransmitters are essential for regulating mood, movement, and autonomic functions within the body.

The assessment of AADC enzyme activity can help diagnose AADC deficiency—a rare but serious condition that affects neurotransmitter synthesis, leading to developmental delays, movement disorders, and autonomic dysfunction. By evaluating this marker, healthcare providers can gain insights into a patient's neurotransmitter production capabilities, guiding diagnosis and treatment strategies for conditions influenced by neurotransmitter levels. This makes the Aromatic L-amino acid decarboxylase enzyme a significant point of interest for researchers and clinicians alike, offering a window into the complex interplay of genetics, enzyme activity, and neurological health.

Fecal Arsenic (As) provides an estimate of a very recent oral exposure to the element, and to a much lesser extent, As that has been excreted from the body in bile. Inorganic As accumulates in hair, nails, skin, thyroid gland, bone and the gastrointestinal tract. Non-toxic organic As (shellfish) is rapidly excreted, primarily in the urine and to a lesser extent in the feces.

Arsenic circulating in the blood will bind to protein by formation of a covalent complex with sulfhydryl groups of the amino acid cysteine. Keratin, the major structural protein in hair and nails, contains many cysteine residues and, therefore, is one of the major sites for accumulation of arsenic. Since arsenic has a high affinity for keratin, the concentration of arsenic in hair is higher than in other tissues. Arsenic binds to keratin at the time of exposure, "trapping" the arsenic in hair. Therefore, hair analysis for arsenic is not only used to document that an exposure occurred, but when it occurred. Hair collected from the nape of the neck can be used to document recent exposure. Axillary or pubic hair is used to document long-term (6 months-1 year) exposure.

Sources:

Found in water, air, soil, cigarettes, and cosmetics. Food grown in contaminated water sources, such as rice and vegetables, or fish, are a common source. Major sources of occupational exposureis the manufacture of pesticides, herbicides, and agricultural products.

90% of all arsenic produced is used as a preservative for wood to prevent rotting and decay. Copper chromated arsenate (CCA), also known as pressure-treated wood, wasphased out for residential use in 2003, but wood treated prior could still be in existing structures. CCA-treated wood is still used in industrial applications. 

Organic arsenic found in seafood is relatively nontoxic, while the inorganic forms are toxic.

Exposure to arsenic-laden drinking water can induce symptoms of gastroenteritis and lead to cancer, diabetes, and neurological and vascular dysfunction. Long-term arsenic exposure in drinking water shows a dose-response relationship to carotid atherosclerosis. The mechanism involves the induction of expression of genes coding inflammatory mediators. Arsenic has also been linked to dermatosis and cancers of the skin, bladder, and lung. Dietary arsenic is contributed by various foods including cereals and breads, 18.1%; starchy vegetables, 14.9%; and meats and fish, 32.1% of total average daily intake.