Luteolin Supplementation Prevents Selenite-Induced Cataractogenesis inSprague DawleyRat Pups

Protective Effects of Trimetazidine in Retarding Selenite-Induced Lens Opacification

Purpose: Cataracts are the leading cause of vision loss worldwide, and the over-production of reactive oxygen species (ROS) is the foremost underlying cause of cataracts. Reducing ROS levels can efficiently prevent lens opacification, as evidenced by many studies. Here, we inhibited ROS overproduction with trimetazidine (TMZ), which is an antioxidant, to explore the therapeutic effects of TMZ and the mechanism of lens opacification.Materials and methods: Sodium selenite-induced cataract formation resulted in a significant loss of lens transparency. This effect could be efficiently rescued by TMZ, which was further found to be an inhibitor of ROS production, as determined by assaying oxidative stress-related parameters (SOD activity, MDA, ·OH and H₂O₂ levels) during cataract formation. The experimental protocols involving animal research were approved by the Animal Care and Ethics Committee of Wenzhou Medical University and conducted according to the Association for Research in Vision and Ophthalmology under the guidelines of the Animal Welfare Act (SYXK 2015-0009).Results: Our study found that TMZ can retard the onset and progression of lens opacification in vivo in experiments using Sprague-Dawley (SD) suckling rats and can rescue the morphology of HLEB₃ cells in vitro. The flow cytometry and DNA fragmentation assays showed that TMZ could prevent sodium selenite-induced apoptosis. The western blot analysing showed that the levels of apoptosis-associated Bcl-2 and Nrf2 were dramatically decreased following the sodium selenite treatment. In addition, the bisulfate DNA sequencing revealed that the demethylation of CpGs in the promoter region of Keap1 was stimulated, and that this demethylation could be inhibited by TMZ by rescuing the Nrf2 expression level.Conclusions: Our findings indicate that the antioxidant TMZ strongly reduces ROS production, which ultimately delays the progression of cataract formation, suggesting that treatment with TMZ represents a novel, promising antioxidant protection to retard cataract formation.

Novel extraction techniques and pharmaceutical activities of luteolin and its derivatives

Luteolin is a 3', 4', 5, 7 tetra hydroxyl flavonoid that exits in many plants, fruits, and vegetable. Many methods of extraction, isolation, and purification are being used, and therapeutic properties are being under discussion due to its valuable role in nutrition and human health. In this review, we have summarized conventional and novel extraction techniques from most recent research on luteolin, its derivatives, and its biological activities. Maceration, soxhlet, reflux, hydrodistillation, ultrasound-assisted extraction, microwave-assisted extraction, ultrasound microwave-assisted extraction, enzyme-assisted extraction, supercritical fluid extraction, and high-speed counter-current chromatography extraction techniques are being used for isolation and purification of these phytochemicals. The anti-inflammatory, anti-cancer, antioxidant, antiviral, heart protective, neurological impairments protection, anti-aging, and whiting properties have been discussed in this review. The literature suggests luteolin and its derivative has many promising health benefits and its therapeutic activity is strongly associated with isolating and purifying solvents and extraction techniques. PRACTICAL APPLICATIONS: This review aims to highlight the sources, novel extraction techniques, and pharmaceutical properties of luteolin. This review provides enough knowledge about how to get maximum extraction yield of luteolin using the novel extraction techniques. Because its therapeutic activity is strongly associated with isolating and purifying solvents and techniques.

Effect of Moringa oleifera stem extract on hydrogen peroxide-induced opacity of cultured mouse lens

Background

Moringa oleifera, also known as horseradish tree or drumstick tree, has strong antioxidant properties. In the present study, we investigated the potential effect of Moringa oleifera stem extract (MOSE) on cataract formation induced by oxidative stress in cultured mouse lenses.

Methods

Mouse lenses cultured in vitro were pretreated with MOSE (0.5 and 1 mg/mL) for 24 h. Then, 1 mM hydrogen peroxide was added, and mouse lenses were cultured for a further 24 h. The medium was then changed to normal culture medium. After 48 h, lens opacification, reactive oxygen species (ROS) generation, reduced glutathione (GSH) content, and activities of superoxide dismutase (SOD) and catalase (CAT) were measured in lens tissues. In addition, the protein expression of peroxisome proliferator-activated receptor alpha (PPARα), a nuclear receptor with potential benefits to improve vision-threatening eye diseases, was assayed.

Results

MOSE (1 mg/mL) alleviated lens opacification, reduced ROS generation, increased GSH content, and elevated SOD and CAT activities in cultured lenses. Moreover, MOSE upregulated the expressions of SOD, CAT, and PPARα.

Conclusions

This study showed that MOSE alleviates oxidative stress-induced cataract formation, and the mechanism of the effect is mainly related to its improvement of the endogenous antioxidant system in the lens.

Electronic supplementary material

The online version of this article (10.1186/s12906-019-2555-z) contains supplementary material, which is available to authorized users.

Rosmarinic Acid Restores Complete Transparency of Sonicated Human Cataract Ex Vivo and Delays Cataract Formation In Vivo

Cataract, the leading cause of vision impairment worldwide, arises from abnormal aggregation of crystallin lens proteins. Presently, surgical removal is the only therapeutic approach. Recent findings have triggered renewed interest in development of non-surgical treatment alternatives. However, emerging treatments are yet to achieve full and consistent lens clearance. Here, the first ex vivo assay to screen for drug candidates that reduce human lenticular protein aggregation was developed. This assay allowed the identification of two leading compounds as facilitating the restoration of nearly-complete transparency of phacoemulsified cataractous preparation ex vivo. Mechanistic studies demonstrated that both compounds reduce cataract microparticle size and modify their amyloid-like features. In vivo studies confirmed that the lead compound, rosmarinic acid, delays cataract formation and reduces the severity of lens opacification in model rats. Thus, the ex vivo assay may provide an initial platform for broad screening of potential novel therapeutic agents towards pharmacological treatment of cataract.

Anthraquinones and flavonoids of Cassia tora leaves ameliorate sodium selenite induced cataractogenesis in neonatal rats

The present study was undertaken to evaluate the efficacy ofCassia toraleaves, an edible plant traditionally used for eye ailments, in preventing experimental cataractogenesis.