Tryptophan Metabolism (Degradation) and the Kynurenine Pathway

The video explains the kynurenine pathway, which degrades tryptophan, an essential amino acid. Tryptophan is crucial for producing serotonin and melatonin. The pathway involves enzymes like IDO and TDO, activated by stress and cytokines, leading to metabolites such as quinolinic acid, which has neurotoxic effects and is linked to psychiatric disorders. Diseases like depression, ALS, and Parkinson's are associated with disruptions in this pathway. The video concludes with a call to action for viewers to engage with the content.

What is the primary role of tryptophan in the body?

• It is a source of energy.

• It is a vitamin.

• It is a precursor for serotonin and melatonin.

• It is a structural component of DNA.

Which enzyme is activated by cortisol in the kynurenine pathway?

• Kynurenine aminotransferase

• Kynurenine hydroxylase

• Tryptophan dioxygenase

• Indoleamine 2-3 dioxygenase

What is the effect of the kynurenine pathway on serotonin levels?

• Increases serotonin production

• Decreases serotonin production

• Has no effect on serotonin

• Converts serotonin into melatonin

Which metabolite of the kynurenine pathway is known to have neurotoxic effects?

• 5-hydroxytryptamine

• Quinolinic acid

• Picolinic acid

• Melatonin

What genetic condition is associated with a deficiency in the enzyme kynureninase?

• Hydroxyquinoline anuria

• Major depressive disorder

• Parkinson's disease

• Amyotrophic lateral sclerosis

Which mood disorder is linked to disruptions in the kynurenine pathway?

• Schizophrenia

• Major depressive disorder

• Anxiety disorder

• Bipolar disorder

Which of the following diseases is NOT mentioned as being associated with the kynurenine pathway?

• Amyotrophic lateral sclerosis

• Major depressive disorder

• Parkinson's disease

• Alzheimer's disease