Phase II Liver Detoxification

<a href="http://www.ncbi.nlm.nih.gov/pubmed/12615076" target="_blank">A phase II detoxification enzyme inducer from lemongrass: identification of citral and involvement of electrophilic reaction in the enzyme induction.</a>

This is called the conjugation pathway, whereby the liver cells add another substance (eg. cysteine, glycine or a sulphur molecule) to a toxic chemical or drug, to render it less harmful. This makes the toxin or drug water-soluble, so it can then be excreted from the body via watery fluids such as bile or urine.

Major Phase II pathways

<ul>

<li>Glutathione</li>

<li>Sulphate</li>

<li>Glycine</li>

<li>Glucuronide conjugations</li>

</ul>

Through conjugation, the liver is able to turn drugs, hormones and various toxins into water soluble excretable substances. Individual xenobiotics and metabolites usually follow one or two distinct pathways. This makes testing of the various pathways possible by challenging with known substances.

Sulphur containing foods and amino acids stimulate phase II detoxification

For efficient phase two detoxification, the liver cells require sulphur-containing amino acids such as taurine and cysteine. The nutrients glycine, glutamine, choline and inositol are also required for efficient phase two detoxification.

Eggs and cruciferous vegetables (eg. broccoli, cabbage, Brussels sprouts, cauliflower), raw garlic, onions, leeks and shallots are all good sources of natural sulphur compounds to enhance phase two detoxification. Thus, these foods can be considered to have a cleansing action.

The phase two enzyme systems include both UDP-glucuronyl transferase (GT) and glutathione-S-transferase (GSH-T).

Glutathione-S-transferase

Glutathione-S-transferase is the most powerful internal antioxidant and liver protector. It can be depleted by large amounts of toxins and/or drugs passing through the liver, as well as starvation or fasting. Phase II reactions may follow Phase I for some molecules or act directly on the toxin or metabolite.

Substrates of the glycine pathway

Salicylates and benzoates are detoxified primarily through glycination. Benzoate is present in many food substances and is widely used as a food preservative. Many other substances are detoxified as well via the glycine conjugation pathway. Patients suffering from xenobiotic overloads and environmental toxicity may not have sufficient amounts of glycine to cope with the amount of toxins they are carrying.

Substrates of the sulphation pathways

Neurotransmitters, steroid hormones, certain drugs such as Acetaminophen (also known as paracetamol) and many xenobiotic and phenolic compounds.

Substrates of glucuronidation

Polycyclic aromatic hydrocarbons, steroid hormones, some nitrosamines, heterocyclic amines, some fungal toxins, and aromatic amines. It also removes "used" hormones, such as estrogen and T4 (thyroid hormone) that are produced naturally by the body.

<a href="https://www.carahealth.com/clinic/liver-heavy-metal-plastic-detox/phase-1-2-liver-detoxification">Source</a>