Higher iron stores and the HFE 187C>G variant delay onset of peripheral neuropathy during combination antiretroviral therapy

Association of cytokine gene polymorphisms with peripheral neuropathy susceptibility in people living with HIV in Greece

Relatively little research has been done in recent years to understand what leads to the unceasingly high rates of HIV sensory neuropathy despite successful antiretroviral treatment. In vivo and in vitro studies demonstrate neuronal damage induced by HIV and increasingly identified ART neurotoxicity involving mitochondrial dysfunction and innate immune system activation in peripheral nerves, ultimately all pathways resulting in enhanced pro-inflammatory cytokine secretion. Furthermore, many infectious/autoimmune/malignant diseases are influenced by the production-profile of pro-inflammatory and anti-inflammatory cytokines, due to inter-individual allelic polymorphism within cytokine gene regulatory regions. Associations of cytokine gene polymorphisms are investigated with the aim of identifying potential genetic markers for susceptibility to HIV peripheral neuropathy including ART-dependent toxic neuropathy. One hundred seventy-one people living with HIV in Northern Greece, divided into two sub-groups according to the presence/absence of peripheral neuropathy, were studied over a 5-year period. Diagnosis was based on the Brief Peripheral Neuropathy Screening. Cytokine genotyping was performed by sequence-specific primer-polymerase chain reaction. Present study findings identify age as an important risk factor (p < 0.01) and support the idea that cytokine gene polymorphisms are at least involved in HIV peripheral-neuropathy pathogenesis. Specifically, carriers of IL1a-889/rs1800587 TT genotype and IL4-1098/rs2243250 GG genotype disclosed greater relative risk for developing HIV peripheral neuropathy (OR: 2.9 and 7.7 respectively), while conversely, carriers of IL2+166/rs2069763 TT genotype yielded lower probability (OR: 3.1), all however, with marginal statistical significance. The latter, if confirmed in a larger Greek population cohort, may offer in the future novel genetic markers to identify susceptibility, while it remains significant that further ethnicity-oriented studies continue to be conducted in a similar pursuit.

Genetics of Iron Metabolism and Premenstrual Symptoms: A Mendelian Randomization Study

BACKGROUND

Many women of reproductive age experience adverse psychological and physiological premenstrual symptoms. These symptoms may last for most of the reproductive years and can negatively affect the quality of life of many women. Some studies have examined the role of micronutrients in premenstrual symptoms, but the research on iron has been limited.

OBJECTIVES

The objective of this study was to evaluate the effects of genetic predictors of iron overload and low iron status on premenstrual symptoms using Mendelian randomization.

METHODS

We examined 254 White females aged 20-29 y from the Toronto Nutrigenomics and Health Study. DNA was isolated from peripheral white blood cells and genotyped for the homeostatic regulatory iron gene (HFE; rs1800562 and rs1799945), transmembrane protease serine 6 (TMPRSS6; rs482026), transferrin receptor 2 (TFR2; rs3811647), and transferrin (TF; rs738584) polymorphisms. Risk of iron overload or low iron status was determined based on combined genotypes. Binomial logistic regressions were carried out to examine the association between genetic risk of iron overload or low iron status and the presence of premenstrual symptoms.

RESULTS

Compared with participants with typical risk of iron overload, those with an elevated risk of iron overload were less likely to experience premenstrual symptoms of confusion (OR: 0.13; 95% CI: 0.02, 1.00), headaches (OR: 0.28; 95% CI: 0.08, 0.98), and nausea (OR: 0.13; 95% CI: 0.02, 0.99) after adjusting for BMI, age, and vitamin C and calcium intake. No associations were seen with the other symptoms. There were also no associations between low iron status genotypes and premenstrual symptoms.

CONCLUSIONS

This Mendelian randomization study demonstrates that women with an elevated risk of iron overload may have a lower risk of experiencing some premenstrual symptoms (headache, confusion, and nausea), suggesting that iron status could impact the risk of certain premenstrual symptoms.