Effect of standardized fruit extract of Luffa cylindrica on oxidative stress markers in hydrogen peroxide induced cataract

Protective effect of Luffa cylindrica Roemer against dexamethasone-induced muscle atrophy in primary rat skeletal muscle cells

Glucocorticoids (GCs) are commonly used in the treatment of chronic inflammatory conditions. However, the administration of high doses and long-term use of GCs can induce muscle atrophy (MA) in patients, leading to a decline in quality of life and increased mortality. MA leads to protein degradation in skeletal muscle, resulting in a reduction of muscle mass. This process is triggered by GCs like dexamethasone (DEX), which induce the expression of E3 ubiquitin ligases, namely Atrogin-1 and muscle RING-finger protein-1 (MuRF1). In this study, we examined the anti-MA potential of Luffa cylindrica Roemer (LCR) on DEX-treated primary skeletal myotubes. Primary skeletal myotubes stimulated with LCR alone resulted in a significant upregulation of myotube development, characterized by an increase in both the number and diameter of myotubes. Contrastingly, combined treatment with LCR and DEX reduced the expression of Atrogin-1, while treatment with DEX alone induced the expression of MuRF1. Furthermore, LCR treatment successfully restored the number and diameter of myotubes that had been diminished by DEX treatment. These findings suggest that LCR holds potential for treating MA, as an accelerating effect on muscle development and anti-MA effects on primary skeletal muscle cells were observed.

Fruit and vegetable intake and the risk of cataract: insights from the UK Biobank study

PURPOSE

A prospective cohort study to investigate the association between fruit and vegetable (F&V) intake and the risk of cataract.

METHODS

We included 72,160 participants who were free of cataract at baseline from the UK Biobank. Frequency and type of F&V intake were assessed using a web-based 24 h dietary questionnaire from 2009 to 2012. Development of cataract during the follow-up was defined by self-report or hospital inpatient records up to 2021. Cox proportional regression models were used to estimate the association between F&V intake and incident cataract.

RESULTS

During a mean follow-up of 9.1 years, 5753 participants developed cataract with a corresponding incidence of 8.0%. After adjusting for multiple demographic, medical and lifestyle covariates, higher intake of F&V were associated with a lower risk of cataract (≥6.5 vs. <2 servings/week: hazards ratio [HR]: 0.82, 95% CI: 0.76 to 0.89; P < 0.0001). Regarding specific types, significant reduced risk of cataract was found for higher intake of legumes (P = 0.0016), tomatoes (≥5.2 vs. <1.8 servings/week: HR: 0.94, 95% CI: 0.88 to 1.00), and apple and pear (>7 vs. <3.5 servings/week: 0.89, 95% CI: 0.83 to 0.94; P < 0.0001), but not for cruciferous vegetables, green leafy vegetables, berry, citrus fruit or melon. Smokers were found to benefit more from F&V intake than former and never smokers. Men also could benefit more from higher vegetable intake than women.

CONCLUSIONS

More F&V intake, especially legumes, tomatoes, apple, and pear, was associated with a lower risk of cataract in this UK Biobank cohort.

Phytochemical Studies, Antioxidant Potential, and Identification of Bioactive Compounds Using GC-MS of the Ethanolic Extract of Luffa cylindrica (L.) Fruit

Luffa cylindrica (L.) is a medicinal plant associated with Cucurbitaceae family which is also known as loofah/sponge gourd, comprising a series of phytochemicals such as chlorophylls, carotenoids, oleanolic acid, saponin, and triterpenoids. The study was carried out to investigate and characterize the bioactive components of ethanolic extract of L. cylindrica. Whole fruit of L. cylindrica was collected, shade dried, pulverized, and extracted successively with ethanol by Soxhlet percolation technique. The crude extracts were later exposed to gas chromatography-mass spectrometry analysis. The profile of the extracts was analyzed for a wide range of secondary metabolites and characterized spectroscopically. A total of 18 components were identified in the ethanolic extract respectively. Prevailing pharmacologically active compounds benzaldehyde, 2-hydroxy-4-methyl-, 4-acetoxy-2-azetidinone, N-decanoic acid, oxirane,2-butyl-3-methyl-, cis, and 3,4-furandiol, tetrahydro-, cis- were present. The extracted compounds were articulated by comparing their retention time and peak area besides the interpretation of mass spectra. Thus, the current study reveals the presence of promising, bioactive components which in turn provides a strength to explore biological activity. In silico molecular docking could be performed for Alzheimer receptors and studied for its activity. Nevertheless, additional studies are required to carry out its bioactivity exploration and toxicity profile.

Comparison of methods to experimentally induce opacification and elasticity change in ex vivo porcine lenses

At the moment, cataract, which is the opacification of the eye’s lens, can only be treated by surgery. In order to develop and test new pharmacological treatment strategies for the disease, there is a need for an appropriate in vitro model using ex vivo animal lenses. In this study, porcine lenses were incubated in either culture medium, glucose, triamcinolone acetonide, sodium chloride, hydrogen peroxide, sodium selenite, neutral buffered formalin, or were exposed to microwave heating to experimentally induce lens opacification. Changes in the lens morphology, weight, size, and elasticity were monitored 7 days after treatment. The fastest induction of dense opacification was seen in lenses exposed to sodium chloride, neutral buffered formalin, and microwave heating. No change in the size and weight of the lenses were detected, whereas loss in elasticity could be detected in lenses treated with formalin solution or microwave heating. Thus, neutral buffered formalin- and microwave-treated ex vivo porcine lenses seem to be a suitable model for mature cataracts, whereas hypertonic sodium chloride may be useful for studies on osmolarity-induced lens opacification.

A mutation in LacDWARF1 results in a GA-deficient dwarf phenotype in sponge gourd (Luffa acutangula)

KEY MESSAGE

A dwarfism gene LacDWARF1 was mapped by combined BSA-Seq and comparative genomics analyses to a 65.4 kb physical genomic region on chromosome 05. Dwarf architecture is one of the most important traits utilized in Cucurbitaceae breeding because it saves labor and increases the harvest index. To our knowledge, there has been no prior research about dwarfism in the sponge gourd. This study reports the first dwarf mutant WJ209 with a decrease in cell size and internodes. A genetic analysis revealed that the mutant phenotype was controlled by a single recessive gene, which is designated Lacdwarf1 (Lacd1). Combined with bulked segregate analysis and next-generation sequencing, we quickly mapped a 65.4 kb region on chromosome 5 using F2 segregation population with InDel and SNP polymorphism markers. Gene annotation revealed that Lac05g019500 encodes a gibberellin 3β-hydroxylase (GA3ox) that functions as the most likely candidate gene for Lacd1. DNA sequence analysis showed that there is an approximately 4 kb insertion in the first intron of Lac05g019500 in WJ209. Lac05g019500 is transcribed incorrectly in the dwarf mutant owing to the presence of the insertion. Moreover, the bioactive GAs decreased significantly in WJ209, and the dwarf phenotype could be restored by exogenous GA3 treatment, indicating that WJ209 is a GA-deficient mutant. All these results support the conclusion that Lac05g019500 is the Lacd1 gene. In addition, RNA-Seq revealed that many genes, including those related to plant hormones, cellular process, cell wall, membrane and response to stress, were significantly altered in WJ209 compared with the wild type. This study will aid in the use of molecular marker-assisted breeding in the dwarf sponge gourd.

Protective Action of Hydrogen Sulfide-Releasing Compounds against Oxidative Stress-Induced Cataract Formation in Cultured Bovine Lenses

PURPOSE

The gaseous signalling molecule, hydrogen sulfide (H₂S) has antioxidant, anti-inflammatory and anti-apoptotic properties. Since oxidative stress has been implicated in the pathogenesis of cataracts and lenticular hydrogen peroxide (H₂O₂) is elevated in some cataract patients, the present study investigated the ability of H₂S-releasing compounds to prevent H₂O₂-induced cataract formation in cultured bovine lenses.

METHODS

Lenses were cultured in either Dulbecco's Modified Eagle Medium (DMEM; control); H₂O₂ (50 mM); ascorbic acid (AA; 3 mM) (positive control); and the H₂S-releasing compounds (diallyl trisulfide [DATS] or GYY4137) in the presence of H₂O₂ (50 mM). Lens opacity was determined using a plate reader to measure transmittance. Lens glutathione content (GSH), superoxide dismutase (SOD) activity and lactate dehydrogenase (LDH) cytotoxicity were assessed before and after treatment with the H₂S-releasing compounds.

RESULTS

Both DATS (10^-7M - 10^-4M) and GYY4137 (10^-7M - 10^-4M) significantly (p < .001) attenuated H₂O₂ (50 mM)-induced loss in transmittance, with DATS (10^-4M) and GYY4137 (10^-7M) achieving a maximal reversal of opacity by 56.86 ± 0.01% (n = 6) and 8.39 ± 0.11% (n = 6) after 120 hours, respectively. These observations were corroborated by photographic evaluation, where DATS (10^-5M - 10^-4M) and GYY4137 (10^-7M - 10^-5M)-treated lenses had relatively clear grids after 120 hours, compared to H₂O₂ (50 mM)-treated lenses. The H₂O₂ (50 mM)-induced decline in total GSH content and total SOD activity were significantly (p < .001; n = 5) reversed by DATS (10^-4M) and GYY4137 (10^-7M). After 24 hours, DATS (10^-4M) and GYY4137 (10^-7M) significantly (p < .001; n = 4) reduced cytotoxicity of primary bovine lens epithelial cells by 33.88 ± 4.59% and 36.19 ± 10.53%, respectively.

CONCLUSION

Both H₂S-releasing compounds protected cultured bovine lenses against oxidative stress-induced cataract formation. The slow-releasing H₂S compound, GYY4137 was more potent than DATS in restoring lenticular total GSH content and total SOD activity along with reducing H₂O₂ (50 mM)-induced cytotoxicity.

Current Trends in the Pharmacotherapy of Cataracts

Cataracts, one of the leading causes of preventable blindness worldwide, refers to lens degradation that is characterized by clouding, with consequent blurry vision. As life expectancies improve, the number of people affected with cataracts is predicted to increase worldwide, especially in low-income nations with limited access to surgery. Although cataract surgery is considered safe, it is associated with some complications such as retinal detachment, warranting a search for cheap, pharmacological alternatives to the management of this ocular disease. The lens is richly endowed with a complex system of non-enzymatic and enzymatic antioxidants which scavenge reactive oxygen species to preserve lens proteins. Depletion and/or failure in this primary antioxidant defense system contributes to the damage observed in lenticular molecules and their repair mechanisms, ultimately causing cataracts. Several attempts have been made to counteract experimentally induced cataract using in vitro, ex vivo, and in vivo techniques. The majority of the anti-cataract compounds tested, including plant extracts and naturally-occurring compounds, lies in their antioxidant and/or free radical scavenging and/or anti-inflammatory propensity. In addition to providing an overview of the pathophysiology of cataracts, this review focuses on the role of various categories of natural and synthetic compounds on experimentally-induced cataracts.

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.

Medicinal Plants and Natural Products Used in Cataract Management

Cataract is the leading reason of blindness worldwide and is defined by the presence of any lens opacities or loss of transparency. The most common symptoms of cataract are impaired vision, decreased contrast sensitivity, color disturbance, and glare. Oxidative stress is among the main mechanisms involved in the development of age-related cataract. Surgery through phacoemulsification and intraocular lens implantation is the most effective method for cataract treatment, however, there are chances of serious complications and irreversible loss of vision associated with the surgery. Natural compounds consisting of antioxidant or anti-inflammatory secondary metabolites can serve as potential leads for anticataract agents. In this review, we tried to document medicinal plants and plant-based natural products used for cataract treatment worldwide, which are gathered from available ethnopharmacological/ethnobotanical data. We have extensively explored a number of recognized databases like Scifinder, PubMed, Science Direct, Google Scholar, and Scopus by using keywords and phrases such as “cataract”, “blindness”, “traditional medicine”, “ethnopharmacology”, “ethnobotany”, “herbs”, “medicinal plants”, or other relevant terms, and summarized the plants/phytoconstituents that are evaluated in different models of cataract and also tabulated 44 plants that are traditionally used in cataract in various folklore medical practices. Moreover, we also categorized the plants according to scientific studies carried out in different cataract models with their mechanisms of action.