Lipid peroxidation evaluated in epidermis exfoliated during microdermabrasion is a reliable marker of oxidative stress related to obesity

Melatonin and Indole-3-Propionic Acid Reduce Oxidative Damage to Membrane Lipids Induced by High Iron Concentrations in Porcine Skin

Iron excess in tissues results in increased oxidative damage. Among different tissues, the skin can particularly be severely damaged by oxidative stress, as it is exposed not only to endogenous but also directly to exogenous pro-oxidants. The skin is especially vulnerable to harmful oxidative stress. Melatonin and indole-3-propionic acid (IPA), two indole substances, are efficient antioxidants. This study aims to evaluate the potential protective effects of melatonin and IPA against oxidative damage to membrane lipids (lipid peroxidation (LPO)), induced in porcine skin homogenates by the Fenton reaction (Fe²⁺ + H₂O₂ → Fe³⁺ + ^•OH + OH⁻) when iron is used in extremely high concentrations. Skin homogenates were incubated in the presence of FeSO₄ (2400, 1200, 600, 300, 150 and 75 µM) + H₂O₂ (5 mM) with/without melatonin or IPA. LPO level (MDA + 4-HDA/mg protein) was measured spectrophotometrically. Melatonin, in its highest used concentration (5.0 mM), prevented FeSO₄ (1200 mM)-induced LPO, whereas it was effective in concentrations as low as 2.5 mM against all lower iron concentrations. IPA was protective in concentrations as low as 2.5 mM independently of FeSO₄ concentration. In conclusion, melatonin and IPA effectively protect against oxidative damage to membrane lipids induced by high concentrations of iron in porcine skin; therefore, both can be considered pharmacological agents in the case of disorders associated with excessive iron accumulation in the skin.

Relationship between urine lipid peroxidation, anthropometric parameters and parameters associated with goitre formation in school-age children

INTRODUCTION

Oxidative stress has been implicated in the normal ageing process and the pathogenesis of several diseases, including goitre. The aim of the study was to evaluate the relationship between urine lipid peroxidation (LPO) and anthropometric parameters as well as the parameters associated with goitre formation in children.

MATERIAL AND METHODS

The subjects included 172 healthy children (93 girls and 79 boys) aged 8-15, divided into 4 age groups - group I (8-9 years), group II (10-11 years), group III (12-13 years) and group IV (14-15 years) - and into 2 groups based on the BSA: the BSA-1 group (≤ 0.55 m²) and the BSA-2 group (> 0.55 m²).

RESULTS

The value of LPO was the highest in group I but the difference between the groups was not statistically significant (p = 0.074). In the BSA-1 group, the LPO was higher than in the BSA-2 group (12.75 ±6.90 nmol/ml and 10.79 ±4.86 nmol/ml, respectively; p = 0.023). We found a weak, negative linear correlation between LPO and age (r = -0.216; p < 0.005), body mass (r = -0.153; p < 0.05), height (r = -0.152; p < 0.05) and BSA (r = -0.151; p < 0.05).

CONCLUSIONS

Anthropometric parameters of school-age children independently of age are negatively associated with oxidative damage to membrane lipids, whereas factors promoting goitrogenesis do not contribute to this process.