Retinal neurodegeneration is considered an early event in the pathogenesis of several ocular diseases, such as diabetic retinopathy, age-related macular degeneration, and glaucoma. At present, there is no definitive treatment to prevent the progression or reversal of vision loss caused by photoreceptor degeneration and the death of retinal ganglion cells. Neuroprotective approaches are being developed to increase the life expectancy of neurons by maintaining their shape/function and thus prevent the loss of vision and blindness. A successful neuroprotective approach could prolong patients’ vision functioning and quality of life. Conventional pharmaceutical technologies have been investigated for delivering ocular medications; however, the distinctive structural characteristics of the eye and the physiological ocular barriers restrict the efficient delivery of drugs. Recent developments in bio-adhesive in situ gelling systems and nanotechnology-based targeted/sustained drug delivery systems are receiving a lot of attention. This review summarizes the putative mechanism, pharmacokinetics, and mode of administration of neuroprotective drugs used to treat ocular disorders. Additionally, this review focuses on cutting-edge nanocarriers that demonstrated promising results in treating ocular neurodegenerative diseases.

Background: Curcumin, a providential spice, has its role in protecting the brain from neurodegeneration. Despite its ubiquitous role, it is not exploited alone due to its hampered bioavailability. By restraining the intestinal and liver enzymatic metabolism, one can boost the bioavailability of curcumin and promotes reabsorption of the curcumin. Diclofenac inhibits uridine 5'-diphosphoglucuronosyltransferase enzymes specifically responsible for the metabolism and elimination of curcumin. Lactobacillus rhamnosus is able to synthesize and release the β -d-glucuronidase enzyme, which reverts curcumin into the active form. Objective: In this research, we aim to combine curcumin with Lactobacillus rhamnosus and diclofenac as an adjuvant with curcumin to potentiate anti-Alzheimer effect in mice impaired with memory by scopolamine. Methods: To induce amnesia, scopolamine was used in mice model (1mg/kg, daily for 10 days i.p.). After execution of behavioural tests (Morris Water Maze test), brain and liver were isolated for further neurochemical and histopathology examination. Results: Our finding showed a marked rise in the level of antioxidant enzymes in curcumin with L. rhamnosus and diclofenac compared to curcumin alone. Additionally, the behavioural study revealed that cognition in mice with curcumin adjuvant with L. rhamnosus and diclofenac showed a marked improvement. The histology study proves that curcumin alone possesses less and a non-significant neuroprotective effect as compared to curcumin with L. rhamnosus and diclofenac. Conclusion: This entire outcome ratifies that curcumin with L. rhamnosus and diclofenac has higher activity as compared to curcumin alone, which reversed the cognition in the Alzheimer disease model.

Background: Clinical studies have already revealed the ubiquitous neuroprotective role of curcumin in neuronal deterioration, but it cannot be used alone due to its truncated bioavailability. Currently, many such approaches are functional, which overcome this issue either by increasing the solubility or absorption. These approaches carry a costlier treatment. One more tactic is present but less focused i.e., by limiting the intestine and liver enzymatic metabolism; by this approach, curcumin will be more available for its beneficial outcome. Objective: The goal of this study was to evaluate the impact of Lactobacillus rhamnosus and diclofenac on the neuroprotective effects of curcumin against scopolamine-induced dementia. Methods: Physical parameters involved a novel tank test, T maze test, whereas neurochemical parameters include brain oxidative stress and acetylcholinesterase (Ache) inhibition activity in a zebrafish dementia model. Results: Our results demonstrated that curcumin with Lactobacillus rhamnosus and diclofenac significantly (p<0.05) reduced anxiety, memory deficits, and brain oxidative stress compared to the alone curcumin- treated group. Conclusion: This result approves that curcumin with L.rhamnosus and diclofenac have superior activity compared to curcumin alone. However, further clinical studies are needed to validate these findings.