Nanotherapy offers innovative approach to diabetic retinopathy

Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia. Prolonged hyperglycemia can lead to a variety of chronic complications, including nephropathy, cardiomyopathy, neuropathy, and retinopathy. The International Diabetes Federation predicts that the number of people with diabetes in 2019 was 463 million, and this number is expected to increase to 700 million by 2045.¹ Diabetic retinopathy (DR) is the most common and unique complication of DM and one of the leading causes of preventable blindness in working-age adults.^2-6

Pathways that contribute to the pathogenesis of DR include increased oxidative stress, leading to increased secretion of vascular endothelial growth factor (VEGF), which leads to angiogenesis and vascular permeability; increased oxidative stress leading to leukocyte stasis and subsequent vascular occlusion; glutamate levels Increases lead to neurodegeneration.⁷

Currently, the most successful way to treat DR is to control blood sugar levels. Advanced cases of this condition may require treatments such as laser therapy, anti-VEGF therapy, steroids, or vitrectomy. Laser photocoagulation is used to enhance retinal circulation in patients with altered fundus microcirculation. For individuals with macular edema, anti-VEGF medications are often administered to reduce macular edema and improve vision. In the most severe cases, such as fundus hemorrhage or proliferative vitreoretinopathy, vitrectomy is required.⁸

Despite these treatments, many DR patients continue to experience vision loss and potential side effects. Considering the limited efficacy of traditional drugs due to low bioavailability and potential side effects, as well as the inherent risks of major surgery, nanotechnology has been increasingly integrated into the medical field, providing innovative methods for DR treatment.⁸

Nanotechnology involves the application and properties of materials with dimensions ranging from 0.1 to 100 nanometers. With the rapid development of nanotechnology, it has been widely used in medicine and other various disciplines and fields.^9.10

Due to its small molecular size and versatile functionality, nanotechnology has also been integrated into modern pharmaceutical research, providing solutions to challenges encountered in traditional treatments.^11,12 Nanomedicines can be specifically designed to deliver drugs, reducing or even eliminating side effects. In addition, they can also achieve sustained release, extend the action time of drugs, enhance drug stability, simplify drug storage, and establish new drug delivery routes.

The use of nanoparticles is a novel treatment strategy for DR, and various nanoparticles have been studied. Loading drugs into nanoparticles can overcome several limitations, including enzymatic and chemical degradation, shortened half-life, low solubility in solvents, high doses required to exhibit therapeutic effects, and high toxicity. The main advantages of nanotechnology include small diameter, high blood-retinal barrier penetration, good biocompatibility, and reduced drug degradation in the body to achieve sustained release.² The most commonly used nanoparticles targeting the posterior segment of the eye include nanostructured lipid carriers, polymeric nanoparticles, solid lipid nanoparticles, cationic nanoemulsions, dendrimers, liposomes, and gold nanoparticles.¹³

Extensively studied diabetic retinopathy drugs that can be delivered in nanoparticle form include corticosteroids and anti-angiogenic factors. Corticosteroids such as triamcinolone acetonide, dexamethasone, and fluocinolone acetonide reduce vascular permeability, prevent disruption of the blood-retinal barrier, downregulate VEGF expression and/or production, and inhibit matrix metalloproteinases.^14.15 Recombinant humanized antibodies that exhibit activity against all VEGF-A isoforms, such as bevacizumab, ranibizumab, and pegaptanib, have demonstrated efficacy in the treatment of diabetic retinopathy, diabetic macular edema, and iridogenesis. Effective on blood vessels.¹⁶

Preclinical studies and clinical trials have shown that both corticosteroids and VEGF inhibitors can be delivered in the form of nanoparticles, and they appear to be a promising alternative to traditional systems, which are often associated with very low bioavailability of administered drugs. (5% to 10%) related. .^17-29th

refer to

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