Vitamin C Differentially Impacts the Serum Proteome Profile in Female and Male Mice

Abstract

A suboptimal blood vitamin C (ascorbate) level increases the risk of several chronic diseases. However, the detection of hypovitaminosis C is not a simple task, as ascorbate is unstable in blood samples. In this study, we examined the serum proteome of mice lacking the gulonolactone oxidase (Gulo) required for the ascorbate biosynthesis. Gulo –/– mice were supplemented with different concentrations of ascorbate in drinking water, and serum was collected to identify proteins correlating with serum ascorbate levels using an unbiased label-free liquid chromatography-tandem mass spectrometry global quantitative proteomic approach. Parallel reaction monitoring was performed to validate the correlations. We uncovered that the serum proteome profiles differ significantly between male and female mice. Also, unlike Gulo –/– males, a four-week ascorbate treatment did not entirely re-establish the serum proteome profile of ascorbate-deficient Gulo –/– females to the optimal profile exhibited by Gulo –/– females that never experienced an ascorbate deficiency. Finally, the serum proteins involved in retinoid metabolism, cholesterol, and lipid transport were similarly affected by ascorbate levels in males and females. In contrast, the proteins regulating serum peptidases and the protein of the acute phase response were different between males and females. These proteins are potential biomarkers correlating with blood ascorbate levels and require further study in standard clinical settings. The complete proteomics data set generated in this study has been deposited to the public repository ProteomeXchange with the data set identifier: PXD027019.

Vitamin C modulates the levels of several proteins of the mitochondrial complex III and its activity in the mouse liver

“…Finally, since the ascorbate levels in serum of the exact same mice had already been measured [ 21 ], we determined whether there was a correlation between the ascorbate levels in serum and liver ( Table S2 ). When we analyzed both males and females together (N = 36), we found that the ascorbate levels in liver correlated significantly with the ascorbate levels in serum with a Pearson's correlation coefficient r of 0.9467 ( p -value <0.00001) ( Fig.…”

“…Additional reports have indicated that even before inducing liver injury, vitamin C deficient Gulo −/− mice exhibit metabolic alterations [ 30 ] that impacts liver functions [ 20 , 31 ]. More recently, it has been shown that the levels of several proteins secreted in the blood by the liver correlate positively or inversely with the serum ascorbate concentrations in Gulo −/− mice [ 21 ]. Such proteins are involved in platelet activation response, extracellular matrix−receptor interactions, focal adhesion, carbon metabolism, and complement and coagulation cascades.…”

“…In this context, the Gulo −/− mouse is a relevant model that depends entirely on ascorbate derived from the diet [ 19 ]. Importantly, the levels of ascorbate found in the serum of Gulo −/− mice reflect the amounts of ascorbate provided in drinking water and can be controlled in a non-invasive manner [ 20 , 21 ]. A previous targeted mass spectrometry study on male Gulo −/− mice supplemented with various ascorbate concentrations in their drinking water showed important alterations in their serum metabolic profiles [ 20 ].…”

Quantitative comparison of the actual antioxidant activity of Vitamin C, Vitamin E, and NADH

“…[ 23 ] All operations were carried out in an argon‐filled glovebox. BNAH, [ 19 ] iAscH − , [ 1c ] and t Bu 3 PhO •[ 24 ] were synthesized according to conventional synthetic strategies. The typical synthetic routes of these compounds were provided in the Supporting Information.…”

“…Vitamin C, Vitamin E, and NADH are three important bio‐redox cofactors in vivo, which all can take place as antioxidants. Vitamin C, ascorbic acid (AscH 2 ) (AscH − exists as the predominant form of AscH 2 in physiological pH), is a key biological cofactor, which exists extensively in vivo [ 1 ] as effective one‐electron (including hydrogen atom) or two‐electron (including hydride ion) donor to take part in a wide range of biochemical processes. Generally, Vitamin C is used as an antioxidant for reducing α‐tocopheroxyl radical [ 2 ] or oxidized glutathione, [ 3 ] and as a cofactor for metalloenzymes such as ascorbate oxidase [ 4 ] and cytochrome b561.…”