Putative protective role of lutein and zeaxanthin in diabetic retinopathy

Abstract

Diabetic retinopathy (DR) is one of the most important microvascular complications of diabetes and remains the leading cause of blindness in the working-age individuals. The exact aetiopathogenesis of DR remains elusive despite major advances in basic science and clinical research. Oxidative damage as one of the underlying causes for DR is increasingly being recognised. In humans, three hydroxycarotenoids, lutein (L), zeaxanthin (Z) and -zeaxanthin (MZ), accumulate at the central retina (to the exclusion of all other dietary carotenoids), where they are collectively known as macular pigment. These hydroxycarotenoids by nature of their biochemical structure and function help neutralise reactive oxygen species, and thereby, prevent oxidative damage to the retina (biological antioxidants). Apart from their key antioxidant function, evidence is emerging that these carotenoids may also exhibit neuroprotective and anti-inflammatory function in the retina. Since the preliminary identification of hydroxycarotenoid in the human macula by Wald in the 1940s, there has been astounding progress in our knowledge of the role of these carotenoids in promoting ocular health. While the Age-Related Eye Disease Study 2 has established a clinical benefit for L and Z supplements in patients with age-related macular degeneration, the role of these carotenoids in other retinal diseases potentially linked to oxidative damage remains unclear. In this article, we comprehensively review the literature germane to the putative protective role of two hydroxycarotenoids, L and Z, in the pathogenesis of DR.

Single-step preparation of selected biological fluids for the high performance liquid chromatographic analysis of fat-soluble vitamins and antioxidants

“…It is important to stress that the Mediterranean diet also allows the intake of fat-soluble antioxidants, among which carotenoids, such as lutein, zeaxanthin, astaxanthin, -carotene, -carotene, lycopene, etc., are certainly one of the most well represented groups in foods of vegetal origin [4]. Several studies indicated that these compounds, due to their capacity to scavenge reactive oxygen species (ROS) [5], may exert beneficial effects in different pathological states characterized by increased ROS production, such as neurodegenerations [6], myocardial ischemia [7], diabetic retinopathy [8].…”

Nutrients and chemical composition of Desplatsia dewevrei

“…It is also useful in process of beverage fermentation (Anthony et al, 2001). The valine content of the leaves (3.170 g/100 g) and fruits (2.581 g/100 g) of D. dewevrei was found to be higher to D. guineense (Ayessou et al, 2014;Kumari, Catherina, Katherine, Chew, & Kah-Guan, 2017). Nonessential amino acids are said to be dispensable because the body can synthesize them readily.…”

Adjuvant Therapies in Diabetic Retinopathy as an Early Approach to Delay Its Progression: The Importance of Oxidative Stress and Inflammation

“…Astaxanthin has proven to be efficient against OS as an antioxidant, in addition to having anti-inflammatory and antiapoptotic properties, underlining its importance in neurodegeneration in DR [73]. In preclinical studies, this xanthophyll has shown to decrease OS damage-induced biomarkers and to increase glutamine synthetase concentrations in Müller cells, reducing apoptosis in retinal ganglion cells as seen in Figure 2 [74,75]. Astaxanthin can also regulate glycemic states and reduce insulin resistance and exert an antiinflammatory effect by decreasing the expression of NF-κβ and TNF-α [76] and by inhibiting the expression of proinflammatory molecules such as ICAM-1 and monocyte chemoattractant protein-1 (MCP-1) and angiogenesis via VEGF [66].…”