ABSTRACT
Oxidative stress (OS) is a major disruption in the physiology of the lacrimal functional unit (LFU). Antioxidant enzymes have dual protective activities: antioxidant and antimicrobial activities. Peroxidases have been indistinctly used as markers of the secretory activity of the LFU and implicated in the pathophysiology, diagnosis and treatment of dry eye disease (DED), even though they comprise a large family of enzymes that includes lactoperoxidase (LPO) and glutathione peroxidase (GPO), among others. Assays to measure and correlate OS with other local LFU phenomena have methodological limitations. Studies implicate molecules and reactions involved in OS as markers of homeostasis, and other studies identify them as part of the physiopathology of diseases. Despite these conflicting concepts and observations, it is clear that OS is influential in the development of DED. Moreover, many antioxidant strategies have been proposed for its treatment, including calorie restriction to nutritional supplementation. This review offers a critical analysis of the biological mechanisms, diagnostic outcomes, drug use, dietary supplements, and life habits that implicate the influence of OS on DED.
ABSTRACT
Clinical presentations associated with vitamin A deficiency persist in poor regions globally with the same clinical features as those described centuries ago. However, new forms of vitamin A deficiency affecting the eyes, which have become widespread, as a result of modern societal habits are of increasing concern. Ophthalmic conditions related to vitamin A deficiency require the combined attention of ophthalmologists, pediatricians, internists, dermatologists, and nutritionists due to their potential severity and the diversity of causes. As the eyes and their adnexa are particularly sensitive to vitamin A deficiency and excess, ocular disturbances are often early indicators of vitamin A imbalance. The present review describes the clinical manifestations of hypovitaminosis A with an emphasis on so-called modern dietary disorders and multidisciplinary treatment approaches. The present review also discusses the relationship between retinoic acid therapy and dry eye disease.
Subject(s)
Eye Diseases/etiology , Vitamin A Deficiency/complications , Acne Vulgaris/etiology , Aged , Child, Preschool , Chronic Disease , Eye Diseases/pathology , Humans , Male , Vitamin A/adverse effects , Vitamin A/blood , Vitamin A Deficiency/metabolism , Young AdultABSTRACT
ABSTRACT Clinical presentations associated with vitamin A deficiency persist in poor regions globally with the same clinical features as those described centuries ago. However, new forms of vitamin A deficiency affecting the eyes, which have become widespread, as a result of modern societal habits are of increasing concern. Ophthalmic conditions related to vitamin A deficiency require the combined attention of ophthalmologists, pediatricians, internists, dermatologists, and nutritionists due to their potential severity and the diversity of causes. As the eyes and their adnexa are particularly sensitive to vitamin A deficiency and excess, ocular disturbances are often early indicators of vitamin A imbalance. The present review describes the clinical manifestations of hypovitaminosis A with an emphasis on so-called modern dietary disorders and multidisciplinary treatment approaches. The present review also discusses the relationship between retinoic acid therapy and dry eye disease.
RESUMO As apresentações clínicas associadas à deficiência de vitamina A persistem em regiões pobres ao redor do mundo com os mesmos achados clínicos descritos há séculos. No entanto, novas formas de problemas causados pela vitamina A afetam os olhos, estão associados com os hábitos da sociedade moderna e tem causado preocupação. Eles exigem a atenção dos oftalmologistas, pediatras, internistas, dermatologistas e nutricionistas, devido à sua gravidade e diversidade de causas. Uma vez que os olhos e seus anexos são órgãos muito sensíveis à deficiência e excesso de vitamina A, manifestações oculares podem ser indicadores precoces do desequilíbrio de vitamina A. Essa revisão traz as manifestações clínicas de hipovitaminose A enfatizando os chamados distúrbios dietéticos modernos e formas de abordagem multidisciplinar. E também traz evidências sobre a relação entre a terapia com ácido retinóico e doença do olho seco.
