Interplay between Selenium Levels and Replicative Senescence in WI-38 Human Fibroblasts: A Proteomic Approach.

Selenoproteins are essential components of antioxidant defense, redox homeostasis, and cell signaling in mammals, where selenium is found in the form of a rare amino acid, selenocysteine. Selenium, which is often limited both in food intake and cell culture media, is a strong regulator of selenoprotein expression and selenoenzyme activity. Aging is a slow, complex, and multifactorial process, resulting in a gradual and irreversible decline of various functions of the body.

Selective up-regulation of human selenoproteins in response to oxidative stress.

Selenocysteinse is inserted into selenoproteins via the translational recoding of a UGA codon, normally used as a stop signal. This process depends on the nature of the SECIS element located in the 3'UTR of selenoprotein mRNAs, selenium bioavailability, and possibly exogenous stimuli. To further understand the function and regulation of selenoproteins in antioxidant defense and redox homeostasis, we have investigated how oxidative stress influences selenoprotein expression as a function of different selenium concentrations.

Interplay between selenium levels, selenoprotein expression, and replicative senescence in WI-38 human fibroblasts.

Selenium is an essential trace element, which is incorporated as selenocysteine into at least 25 selenoproteins using a unique translational UGA-recoding mechanism. Selenoproteins are important enzymes involved in antioxidant defense, redox homeostasis, and redox signaling pathways. Selenium levels decline during aging, and its deficiency is associated with a marked increase in mortality for people over 60 years of age.

Selective up-regulation of human selenoproteins in response to oxidative stress.

Selenocysteine is inserted into selenoproteins via the translational recoding of a UGA codon, normally used as a stop signal. This process depends on the nature of the selenocysteine insertion sequence element located in the 3' UTR of selenoprotein mRNAs, selenium bioavailability, and, possibly, exogenous stimuli. To further understand the function and regulation of selenoproteins in antioxidant defense and redox homeostasis, we investigated how oxidative stress influences selenoprotein expression as a function of different selenium concentrations.

Interplay between selenium levels, selenoprotein expression, and replicative senescence in WI-38 human fibroblasts.

Selenium is an essential trace element, which is incorporated as selenocysteine into at least 25 selenoproteins using a unique translational UGA-recoding mechanism. Selenoproteins are important enzymes involved in antioxidant defense, redox homeostasis, and redox signaling pathways. Selenium levels decline during aging, and its deficiency is associated with a marked increase in mortality for people over 60 years of age.

Phenotype-haplotype correlation of IRF5 in systemic sclerosis: role of 2 haplotypes in disease severity.

Objective: Identification of an association between IRF5 rs2004640 and systemic sclerosis (SSc) has highlighted a key role for type 1 interferon (IFN). Additional functional IRF5 variants have been identified as autoimmune susceptibility factors. Our aim was to investigate whether IRF5 haplotypes confer susceptibility to SSc, and to perform genotype haplotype-phenotype correlation analyses.