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.

Arsenic is a natural component of the earth’s crust and is widely distributed throughout the environment in the air, water and land. It is highly toxic in its inorganic form and considered a carcinogenic heavy metal.

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.

Elemental analysis provides a good estimate of exposure to inorganic arsenic (As). However, hair can be contaminated externally with As from air, water, dust, shampoos and soap. Inorganic As, and some organic As compounds, can cause toxicity. Some research suggests that As may beessential at extremely low levels but its function is not understood. Inorganic As accumulates inhair, nails, skin, thyroid gland, bone and the gastrointestinal tract. Organic As is rapidly excreted in the urine.

Urinary arsenic (As) provides an indication of recent or ongoing exposure to various forms of the metalloid. Urine As may also indicate, to a lesser extent, endogenous detoxification of inorganic As. The less toxic organic forms of As from seafood have a circulating half-life of about 48 hours, and are rapidly excreted from the body. Consider very recent shellfish consumption with a finding of high urinary As.

Food, well water, and air are common sources of exposure for As. The predominant dietary source of As is seafood, followed by rice/rice-based products, mushrooms, and poultry (antiparasitics in feed). While fish/shellfish contain the highest levels of As, most abundant are the much less harmful organic As species arsenobetaine and arsenocholine; they are rapidly and efficiently excreted.

Arsenic is a natural component of the earth’s crust and is widely distributed throughout the environment in the air, water and land. It is highly toxic in its inorganic form and considered a carcinogenic heavy metal.

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.

Arsenic is a natural component of the earth’s crust and is widely distributed throughout the environment in the air, water and land. It is highly toxic in its inorganic form and considered a carcinogenic heavy metal.

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.