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DOI: 10.1055/a-2517-4967
In situ Forming Nanoemulgel for Diabetic Retinopathy: Development, characterization, and in vitro efficacy assessment

Abstract
Diabetic retinopathy, the most common microvascular complication of diabetes mellitus, is the leading cause of vision impairment worldwide. Flavonoids with antioxidant properties have been shown to slow its progression. Myricetin, a flavonoid polyphenolic compound, possesses antioxidant properties, but its clinical use in ocular delivery is limited by poor aqueous solubility, stability, and bioavailability. Recently, in situ gels have gained interest as ocular drug delivery vehicles due to their ease of installation and sustained drug release. This study aimed to develop a myricetin-loaded thermoresponsive in situ nanoemulgel to enhance its efficacy in treating diabetic retinopathy. Nanoemulsions were developed via aqueous phase titration using Sefsol 218 as the oil phase, Kolliphore RH40 as the surfactant, and PEG 400 as the co-surfactant. Physicochemical evaluations identified formulation batch ISG17, consisting of 10% oil phase, 30% Smix (1:2), and 60% distilled water, as the optimal formulation. The developed in situ nanoemulgel showed significant enhancement in corneal permeation and retention, which was further confirmed by fluorescence microscopy. Ocular tolerability was demonstrated through corneal hydration tests and histopathology investigations. The antioxidant potential of the myricetin-loaded nanoemulgel was assessed using the DPPH assay. Myricetin was found to be an efficient antioxidant, as indicated by its IC50 values compared to ascorbic acid. The MTT cell viability assay results showed that the developed formulation effectively inhibits the proliferation of Y79 retinoblastoma cells, demonstrating comparable efficacy to the standard marketed preparation Avastin (Bevacizumab injection). In conclusion, the nanoemulsion formulation containing a thermoresponsive polymer for in situ gelling presents a promising drug delivery system, offering superior therapeutic efficacy and better patient compliance for the treatment of diabetic retinopathy.
Publication History
Received: 23 August 2024
Accepted: 27 December 2024
Article published online:
07 February 2025
© 2025. Thieme. All rights reserved.
Georg Thieme Verlag KG
Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany
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References
- 1 Liu Y, Wu N. Progress of nanotechnology in diabetic retinopathy treatment. International journal of nanomedicine. 2021 16. 1391-1403
- 2 Laddha UD, Kshirsagar SJ, Sayyad LS. et al. Development of surface modified nanoparticles of curcumin for topical treatment of diabetic retinopathy: in vitro, ex vivo and in vivo investigation. Journal of Drug Delivery Science and Technology 2022; 76: 103835
- 3 Garcia-Ramírez M, Hernández C, Villarroel M. et al. Interphotoreceptor retinoid-binding protein (IRBP) is downregulated at early stages of diabetic retinopathy. Diabetologia 2009; 52: 2633-2641
- 4 Niisato N, Marunaka Y. Therapeutic potential of multifunctional myricetin for treatment of type 2 diabetes mellitus. Frontiers in Nutrition 2023; 10: 1175660
- 5 Barzegar A. Antioxidant activity of polyphenolic myricetin in vitro cell-free and cell-based systems. Molecular biology research communications 2016; 5: 87
- 6 Matos AL, Bruno DF, Ambrósio AF. et al. The benefits of flavonoids in diabetic retinopathy. Nutrients 2020; 12: 3169
- 7 Kim YS, Kim J, Kim KM. et al Myricetin inhibits advanced glycation end product (AGE)-induced migration of retinal pericytes through phosphorylation of ERK1/2, FAK-1, and paxillin in vitro and in vivo. Biochemical Pharmacology 2015; 93: 496-505
- 8 Liao HH, Zhu JX, Feng H. et al. Myricetin possesses potential protective effects on diabetic cardiomyopathy through inhibiting IκBα/NFκB and enhancing Nrf2/HO-1. Oxidative medicine and cellular longevity. 2017 2017. 8370593
- 9 He Y, Al-Mureish A, Wu N. Nanotechnology in the treatment of diabetic complications: a comprehensive narrative review. Journal of Diabetes Research 2021; 2021: 1-1
- 10 Prajapati BG, Patel AG, Paliwal H. Fabrication of nanoemulsion-based in situ gel using moxifloxacin hydrochloride as model drug for the treatment of conjunctivitis. Food Hydrocolloids for Health 2021; 1: 100045
- 11 Liu R, Sun L, Fang S. et al. Thermosensitive in situ nanogel as ophthalmic delivery system of curcumin: development, characterization, in vitro permeation and in vivo pharmacokinetic studies. Pharmaceutical development and technology 2016; 21: 576-582
- 12 Aithal GC, Nayak UY, Mehta C. et al. Localized in situ nanoemulgel drug delivery system of quercetin for periodontitis: development and computational simulations. Molecules 2018; 23: 1363
- 13 Chowhan A, Giri TK. Polysaccharide as renewable responsive biopolymer for in situ gel in the delivery of drug through ocular route. International journal of biological macromolecules 2020; 150: 559-572
- 14 Soliman KA, Ullah K, Shah A. et al. Poloxamer-based in situ gelling thermoresponsive systems for ocular drug delivery applications. Drug Discovery Today 2019; 24: 1575-1586
- 15 Wu Y, Liu Y, Li X. et al. Research progress of in-situ gelling ophthalmic drug delivery system. Asian journal of pharmaceutical sciences 2019; 14: 1-5
- 16 Bali V, Ali M, Ali J. Study of surfactant combinations and development of a novel nanoemulsion for minimising variations in bioavailability of ezetimibe. Colloids and Surfaces B: Biointerfaces 2010; 76: 410-420
- 17 Srivastava M, Kohli K, Ali M. Formulation development of novel in situ nanoemulgel (NEG) of ketoprofen for the treatment of periodontitis. Drug delivery 2016; 23: 154-166
- 18 Pathak MK, Chhabra G, Pathak K. Design and development of a novel pH triggered nanoemulsified in-situ ophthalmic gel of fluconazole: ex-vivo transcorneal permeation, corneal toxicity and irritation testing. Drug Development and Industrial Pharmacy 2013; 39: 780-790
- 19 Bhalerao H, Koteshwara KB, Chandran S. Design, optimisation and evaluation of in situ gelling nanoemulsion formulations of brinzolamide. Drug Delivery and Translational Research 2020; 10: 529-547
- 20 Morsi N, Ibrahim M, Refai H. et al. Nanoemulsion-based electrolyte triggered in situ gel for ocular delivery of acetazolamide. European journal of pharmaceutical sciences 2017; 104: 302-314
- 21 Abdel-Rashid RS, Helal DA, Omar MM. et al. Nanogel loaded with surfactant based nanovesicles for enhanced ocular delivery of acetazolamide. International Journal of Nanomedicine. 2019: 2973-2983
- 22 Singh S, Kushwaha P, Gupta S. Development and evaluation of thermoresponsive in situ nanoemulgel of myricetin for diabetic retinopathy. Ann Phytomed 2022; 11: 320-326
- 23 The Indian Pharmacopoeia, The Indian Pharmacopoeia Commission: Ghaziabad, India, Published by Ministry of Health and Public Welfare, Government of India, New Delhi 2010 2. 1032
- 24 Nagai N, Minami M, Deguchi S. et al. An in-situ gelling system based on methylcellulose and tranilast solid nanoparticles enhances ocular residence time and drug absorption into the cornea and conjunctiva. Front Bioeng Biotechnol 2020; 8: 764
- 25 Soliman OA, Mohamed EA, Khatera NA. Enhanced ocular bioavailability of fluconazole from niosomal gels and microemulsions: Formulation, optimization, and in vitro–in vivo evaluation. Pharmaceutical Development and Technology 2019; 24: 48-62
- 26 Kaur H, Pancham P, Kaur R. et al. Synthesis and characterization of Citrus limonum essential oil based nanoemulsion and its enhanced antioxidant activity with stability for transdermal application. Journal of Biomaterials and Nanobiotechnology 2020; 11: 215-236
- 27 Wu Q, Bai H, Huang CL. et al. Mechanism study of isoflavones as an anti-retinoblastoma progression agent. Oncotarget 2017; 8: 88401
- 28 Campbell MA, Karras P, Chader GJ. Y-79 retinoblastoma cells: isolation and characterization of clonal lineages. Experimental eye research 1989; 48: 77-85
- 29 Semwal DK, Semwal RB, Combrinck S. et al. Myricetin: A dietary molecule with diverse biological activities. Nutrients 2016; 8: 90
- 30 Destruel PL, Zeng N, Maury M. et al. In vitro and in vivo evaluation of in situ gelling systems for sustained topical ophthalmic delivery: state of the art and beyond. Drug discovery today. 2017; 22: 638-651
- 31 Sheshala R, Kok YY, Ng JM. et al. In Situ Gelling Ophthalmic Drug Delivery System: An Overview and Its Applications. Recent Patents on Drug Delivery & Formulation 2015; 9: 237-248
- 32 Hwang IW, Chung SK. Isolation and identification of myricitrin, an antioxidant flavonoid, from daebong persimmon peel. Preventive nutrition and food science 2018; 23: 341