Microalgae as a Nutraceutical Tool to Antagonize the Impairment of Redox Status Induced by SNPs: Implications on Insulin Resistance

Abstract

Microalgae represent a growing innovative source of nutraceuticals such as carotenoids and phenolic compound which are naturally present within these single-celled organisms or can be induced in response to specific growth conditions. The presence of the unfavourable allelic variant in genes involved in the control of oxidative stress, due to one or more SNPs in gene encoding protein involved in the regulation of redox balance, can lead to pathological conditions such as insulin resistance, which, in turn, is directly involved in the pathogenesis of type 2 diabetes mellitus. In this review we provide an overview of the main SNPs in antioxidant genes involved in the promotion of insulin resistance with a focus on the potential role of microalgae-derived antioxidant molecules as novel nutritional tools to mitigate oxidative stress and improve insulin sensitivity.

Keywords: antioxidants; insulin resistance; microalgae; nutraceuticals; oxidative stress; reactive oxygen species; single nucleotide polymorphisms.

Figure 1

Microalgae mitigate the ability of SNPs in inducing oxidative stress and deregulating insulin signaling.

Figure 2

SNPs induced oxidative stress, that could be counteracted by microalgae. Representation of the effect of some polymorphisms on the promotion of oxidative stress leading to a self-maintenance loop via the inflammation pathway. Oxidative stress promotes the phosphorylation of IkB, with the release of NF-kB and its translocation into the nucleus with a consequent expression promotion of pro-inflammatory genes. The molecules produced by microalgae, such as quercetin and EPA, can prevent phosphorylation of IkB and block the self-maintaining loop described above. Other microalgae metabolites such as the carotenoids astaxanthin and β-carotene can promote the translocation of the transcription factor NRF2 from the cytoplasm to the nucleus, as a consequence of the cleavage of its binding to the inhibitor Keap1, promoted by oxidative stress. The NRF2 translocation to the nucleus induced by carotenoids promotes the expression of antioxidant genes through its binding to ARE domains. In addition to the mechanisms mentioned, some microalgae metabolites such as ascorbic acid can reduce the oxidative stress by a direct scavenging activity.