The gender-differentiated antioxidant effects of a lutein-containing supplement in the aqueous humor of patients with senile cataracts

Effects and Mechanisms of Lutein on Aging and Age-Related Diseases

Aging and age-related diseases are serious public health issues that are receiving growing attention from researchers. Lutein has a critical function in the prevention and management of these issues. Possible mechanisms mainly include suppressing inflammation and oxidative stress, regulating cell activity, and modulating the levels of toxic substances. In this narrative review paper, we sum up the most current developments in the study of the effects of lutein on aging and five age-related diseases (age-related macular degeneration, cataracts, Alzheimer's disease, Parkinson's disease, and osteoporosis), and fundamental mechanisms are reviewed. The bioavailability of lutein and the strategies to improve its bioavailability are discussed. This piece of work can bring a clearer comprehension of the protective effects of lutein against aging and age-related diseases and can be also helpful for developing lutein as functional food and dietary supplements for these age-related diseases.

Effects of Recombinant Human Epidermal Growth Factor Eye Drops Combined with Phacoemulsification on Short- and Long-Term Visual Acuity Recovery and Related Dry Eye Complications in Patients with Senile Cataract

Objective

To investigate the effects of recombinant human epidermal growth factor eye drops combined with phacoemulsification on short- and long-term visual acuity recovery and related dry eye complications in patients with senile cataract.

Methods

Sixty patients with senile cataract cured from January 2019 to January 2021 were enrolled in our hospital. The patients in the control group were arbitrarily assigned into the control and the research group. The former group received phacoemulsification, and the latter group received recombinant human epidermal growth factor (RhEGF) eye drops combined with phacoemulsification. The curative effect, the incidence of xerophthalmia, short-term and long-term vision improvement, changes of corneal endothelial cells, serum factors, and life quality scores were compared.

Results

The effective rate of the research group was 90.00%, and the effective rate of the control group was 66.67%; the curative effect of the research group was higher than that of the control group (P < 0.05). The incidence of dry eye in the research group was lower than that in the control group (P < 0.05). The short-term and long-term visual acuity improvement effect of the research group was better than that of the control group (P < 0.05). After treatment, the density of corneal endothelial cells in the research group was higher than that in the control group, while the proportion of hexagonal cells and the coefficient of variation of corneal endothelial cells in the research group were lower than those in the control group (P < 0.05). After treatment, IL-6 and TNF-α in the research group were lower than those in the control group (P < 0.05). Compared with the control group, the physical function, psychological function, social function, and healthy self-cognition scores of the research group were all lower (P < 0.05).

Conclusion

Cataract is the leading cause of blindness in the world. With the continuous improvement of cataract phacoemulsification technology, the incidence of some serious complications has gradually lessened. Xerophthalmia is one of the most obvious and predictable complications after cataract surgery and may affect the recovery of postoperative visual acuity. Recombinant human epidermal growth factor eye drops can effectively enhance the visual acuity of patients, promote the curative effect, and strengthen the life quality.

Changes in Aqueous Humor Lutein Levels of Patients with Cataracts after a 6-Week Course of Lutein-Containing Antioxidant Supplementation

PURPOSE

Oxidative damage is known to be an important cause of age-related cataracts and it has been suggested that administration of antioxidants, such as lutein, may delay the onset and progression of cataracts. Our previous investigation of human aqueous humor after the intake of a lutein-containing supplement demonstrated decreases in peroxidative products. This study evaluated the transportation of lutein into aqueous humor which is an important factor when measuring the antioxidant effects of lutein on the lens.

METHODS

This study enrolled 155 patients with binocular cataracts of the same grade. Serum and aqueous humor samples were collected during cataract surgery before (as pre-intake samples) and after 6 weeks of oral intake of Ocuvite + Lutein^® (as post-intake samples). Lutein levels were measured with high-performance liquid chromatography.

RESULTS

Lutein levels in both the serum and aqueous humor were significantly higher in the post-intake than the pre-intake samples. There were significant increases in the lutein levels in patients with lower pre-intake lutein serum levels. There was also a tendency for greater increases in patients with lower pre-intake aqueous humor lutein levels.

CONCLUSIONS

These results demonstrate that oral lutein supplementation increases lutein levels, which further induce decreases in peroxidation in the aqueous humor. Furthermore, lutein supplementation may be more effective in patients with lower serum lutein levels.

UHPLC-DAD Characterization of Origanum vulgare L. from Atacama Desert Andean Region and Antioxidant, Antibacterial and Enzyme Inhibition Activities

The Lamiaceae family is an important source of species among medicinal plants highly valued for their biological properties and numerous uses in folk medicine. Origanum is one of the main genera that belong to this family. The purpose of the study was to determine the phenolic composition of the Origanum vulgare extract and evaluate the antimicrobial, antioxidant, and inhibitory activities of this species that grows in the Andean region of the Atacama Desert. High-performance liquid chromatography was performed to determine the main phenols. Rosmarinic acid was identified as the predominant phenolic compound in this species (76.01 mg/100 g DW), followed by protocatechuic acid, which to our knowledge, no previous study reported similar concentrations in O. vulgare. The oregano extract exhibited a content of total phenolic (3948 mg GAE/100 g DW) and total flavonoid (593 mg QE/100 g DW) with a higher DPPH antioxidant activity (IC₅₀ = 40.58 µg/mL), compared to the same species grown under other conditions. Furthermore, it was found to inhibit α-glucosidase activity with an IC₅₀ value (7.11 mg/mL) lower than acarbose (129.32 mg/mL). Pseudomonas syringae and Pantoea agglomerans (both MIC 0.313 mg/mL and MBC 1.25 mg/mL) were the bacteria most susceptible to oregano extract with the lowest concentration necessary to inhibit bacterial growth. These results open the door for the potential use of this plant to manage chronic diseases, and they expand the knowledge of the species cultivated in arid environmental conditions.

Comparative study between lutein and its liposomal form on cisplatin-induced retinal injury in rabbits

Aim: Lutein is a potent antioxidant that is found in ocular tissue. It protects retina against oxidative stress. We aimed to increase lutein efficiency by encapsulating it into liposome and testing its neuroprotective effect against cisplatin-induced retinal injury in rabbits. Materials and methods: Twenty-four male, New Zealand, rabbits weighing 1.5-2 kg were divided into four groups, as follows: group I as a control, group II received cisplatin, group III received free lutein + cisplatin and group IV received liposomal lutein + cisplatin. All treatments were administrated twice per week for 14 days. Electroretinogram (ERG) was recorded for all rabbits just before decapitation. Then, the retinae were subjected to histopathological evaluations and comet assay. Results: Results indicated significant decrease (p ˂ 0.01) in ERG waves, significant increase (p ˂ 0.01) in all parameters of comet assay (% tailed cells, tail length, DNA% in tail and tail moment), severe fragmentation in photoreceptors layer and changes in inner retina after the administration of cisplatin. There were some sort of improvement in ERG, comet assay and the histological results after the administration of lutein with cisplatin, whereas these tests yielded values comparable to control in the liposomal lutein group. Conclusions: Liposomal lutein administration could prevent the detrimental effects of cisplatin on the retina, while avoiding the use any artificial chemicals. The latter might be preferable but with possible highly toxic effects. Results were promising and worse further future investigations.

Nutritional effect on age-related cataract formation and progression

PURPOSE OF REVIEW

To provide a comprehensive summary of the latest evidence-based data on nutrients linked to the pathogenesis of cataract formation and progression.

RECENT FINDINGS

This summary of peer-reviewed publications emphasizes the ongoing effort to modulate the cataractogenous process through nutrition, and points at an only weak evidence for the contribution of a specific nutrient to this process. Although observational studies successfully demonstrated a positive correlation between specific nutrients intake and age-related cataract, such evidence was usually lacking in following interventional studies. Three metanalyses point towards a beneficial effect of high intake of vitamin C, vitamin E and vitamin A on the risk of age-related cataract. New studies point at a protective effect of a high intake of vitamin K1 and vitamin D but negate the influence of Mediterranean diet or an overall high dairy consumption on the progression of cataract in a subgroup of patients. Sterols are candidate nutrients for future investigation.

SUMMARY

Nutrition rich in fruits and vegetables, and a high dietary intake of vitamins A, C, D, E and K1 may be inversely associated with the risk of age-related cataract. More studies involving patients in a wide range of nutritional status are required to establish the long-term benefit of nutritional supplements.

Gender differences in mRNA expression of aquaporin 8 and glutathione peroxidase in cataractous lens following intake of an antioxidant supplement

Antioxidants can decrease oxidative damage and prevent age-related ocular disease. Our previous investigation on human aqueous humor following intake of a lutein-containing antioxidant supplement reported an increase in the scavenging activity of superoxide in both genders and an increase in the amount of hydrogen peroxide (H₂O₂) in females. Aquaporin 8 (AQP8) is a diffusion facilitator of H₂O₂ and glutathione peroxidase (Gpx) is a H₂O₂ scavenging enzyme. The correlation between AQP8 and Gpx may be the key to determining how oxidative stress in the aqueous humor affects the lens after intake of antioxidant supplements. In this study, 24 patients with the same grade of binocular cataract were included. Anterior capsule samples, including lens epithelial cells (LECs), were collected during cataract surgery before (as pre-intake samples) and after 6 weeks of oral intake of Ocuvite Lutein ^® (as post-intake samples). The mRNA expression of APQ8 and Gpx was measured using real-time polymerase chain reaction. Among males, AQP8 expression decreased significantly after the supplementation (P = .03), while there was no statistical change among females. AQP8 expression was significantly correlated to that of Gpx in post-intake samples among females (R = 0.69, P = .02), while no correlation was evident among males. The results suggest antioxidant supplementation may work by different mechanisms on LECs between genders. After supplementation, a decrease in AQP8 in LECs may inhibit the influx of H₂O₂ from the aqueous humor in males. In females however, the correlation between AQP8 and Gpx in LECs may indicate an increase in Gpx activity following the influx of H₂O₂ from the aqueous humor and further scavenging of H₂O₂.

Immunolocation of Aquaporin 8 in Human Cataractous Lenticular Epithelial Cells

Purpose/Aim

Aquaporin 8 (AQP8) is a diffusion facilitator of hydrogen peroxide (H₂O₂) through cell membranes. The purpose of this study was to confirm and localize AQP8 in human lenticular epithelial cells (LECs).

Materials and Methods

Lenticular anterior capsule samples, including LECs, were collected during cataract surgery of cataract patients after informed consent. The localization of AQP8 was detected by immunohistochemical staining using an antibody to AQP8. Real-time polymerase chain reaction (RT-PCR) was also used to determine the AQP8 mRNA expression levels. The PCR products were analyzed by gel electrophoresis following analyses of band density.

Results

Immunohistochemical staining showed AQP8 was distributed throughout the whole area of the anterior capsulotomy. AQP8 labeling was observed surrounding and within the cytoplasm of LECs. RT-PCR and gel electrophoresis also revealed the presence of AQP8 mRNA in the lenticular anterior capsule. The results of immunohistochemical staining were comparable to those of RT-PCR and gel electrophoresis.

Conclusions

The results of this study indicate the distribution of AQP8 in human LECs. This is the first investigation confirming the presence of AQP8 in human LECs.