[Review of nutritional components in Covid-19: what about micronutrients?].

Nutritional status is an important protection factor against viral infections. Both undernutrition and malnutrition cause deficits in micronutrients, trace elements and vitamins necessary for various physiological functions and the appropriate functioning of the immune system. These deficiencies and infectious diseases often coexist, with complex interactions.

Dysregulation of tryptophan catabolism at the host-skin microbiota interface in hidradenitis suppurativa.

Hidradenitis suppurativa (HS) is a chronic skin disorder of unknown etiology that manifests as recurrent, painful lesions. Cutaneous dysbiosis and unresolved inflammation are hallmarks of active HS, but their origin and interplay remain unclear. Our metabolomic profiling of HS skin revealed an abnormal induction of the kynurenine pathway of tryptophan catabolism in dermal fibroblasts, correlating with the release of kynurenine pathway-inducing cytokines by inflammatory cell infiltrates.

Simultaneous analysis of retinol, six carotenoids, two tocopherols, and coenzyme Q10 from human plasma by HPLC.

Lipophilic antioxidant determination is of relevance in health and diseases. Several HPLC methods exists but rare are those including coenzyme Q10 with carotenoids, retinol and tocopherols. Here a single-step extraction was proposed for the detection of retinol, α and γ-tocopherols, lutein, zeaxanthin, trans-ß-carotene, α-carotene, ß-cryptoxanthin and lycopene as well as coenzyme Q10.

Tryptophan metabolism in phenylketonuria: A French adult cohort study.

Many similarities between tryptophan (Trp) and phenylalanine (Phe) metabolisms exist. It is possible that a modification of Trp metabolism might be seen in phenylketonuria (PKU). As some of these metabolites have neuroactive properties, they should be consider in neurological impairment seen in this pathology and not totally explained by blood Phe concentrations.

[Tryptophan metabolism: utility of plasmatic assay in phenylketonuria, a study in 6 adult patients].

Phenylketonuria (PKU, OMIM 261600) is an autosomal recessive inborn error of metabolism caused by a deficiency of the hepatic enzyme phenylalanine hydroxylase (PAH; EC 1.14.16.

Simultaneous determination of tryptophan and 8 metabolites in human plasma by liquid chromatography/tandem mass spectrometry.

Tryptophan (Trp) is an essential amino-acid and the precursor of many biologically active substances such as kynurenine (KYN) and serotonin (5HT). Its metabolism is involved in different physiopathological states, such as cardiovascular diseases, cancer, immunomodulation or depression. Hence, the quantification of Trp catabolites, from both KYN and 5HT pathways, might be usefulfor the discovery of novel diagnostic and follow-up biomarkers.

[Development and analytical validation according COFRAC recommendations of pyruvate and ketone body assay on open automated analyser].

Measurements of pyruvate and ketones bodies (acetoacetate and 3-hydroxybutyrate) are essential to the investigation of intermediary metabolism. Indeed, their blood levels reflect energy balance influenced by nutritional status. This balance can be disturbed in certain diseases such as diabetes and some inherited metabolic disorders.