Improved bioavailability of raloxifene hydrochloride through nasal administration of poly (methyl vinyl ether-co-maleic acid) nanoparticles in ovariectomized rats

Document Type : Original Article

Authors

1 Novel Drug Delivery Systems Research Center, Department of Pharmaceutics, School of Pharmacy, Isfahan University of Medical Sciences, Isfahan, Iran

2 Department of Pharmacology, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran

10.22038/ijbms.2025.90740.19566

Abstract

Objective(s): To improve the low bioavailability of Raloxifene hydrochloride (RH), which is just 2% through oral administration, an in situ mucoadhesive thermoreversible gel loaded with RH nanoparticles was formulated using Pluronic F127. 
Materials and Methods: Mucoadhesion of the gels was modulated using Carbopol 934, Xanthan gum, and HPMC K4M as mucoadhesive polymers. The formulations containing 18% Pluronic and 0.2% Xanthan gum or 0.5% HPMC were considered as the optimized formulation based on their pH, gelation temperature, mucoadhesive strength, gel strength, viscosity, drug content, histopathological, and pharmacodynamic studies in ovariectomized rats. 
Results: The gelation temperatures were 33.63±0.38 °C for Xanthan gum (0.2%) and 37.18±0.71 °C for HPMC (0.5%). Also, the 51758.67±62.17 dyn/cm2 mucoadhesive strength was seen in HPMC 0.5% and 14867.33±192.60 dyn/cm2 in Xanthan gum 0.2%. The drug released from the gel containing HPMC (0.5%) and Xanthan gum (0.2%) at 180 min was 98.2 ± 0.9% and 92.2 ± 5.6%, respectively. Serum calcium, phosphorus, and alkaline phosphatase significantly decreased in ovariectomized rats treated with oral estradiol valerate (as the standard treatment), and ovariectomized rats received nasal gels containing RH nanoparticles in comparison to the group with no treatment (P<0.05). Histopathological results indicated no adverse effects on the nasal mucosa following the administration of RH nanoparticle gels. Also, compared with the untreated drug, the nasal gel of RH nanoparticles showed an AUC0-24 that was 5.5-fold higher, indicating a significant improvement in RH relative bioavailability (P<0.05). 
Conclusion: These results suggest that the thermoreversible nasal gel formulation of RH can be used as a safe drug-delivery system. 

Keywords

Main Subjects


1. Walker MD, Shane E. Postmenopausal osteoporosis. N Engl J Med 2023; 389:1979–1991. 
2. Aibar-Almazán A, Voltes-Mart\’\inez A, Castellote-Caballero Y, Afanador-Restrepo DF, Carcelén-Fraile M del C, and López-Ruiz E. Current status of the diagnosis and management of osteoporosis. Int J Mol Sci 2022; 23:9465-9491. 
3. Anam AK, Insogna K. Update on osteoporosis screening and management. Med Clin 2021; 105:1117–1134. 
4. Foessl I, Dimai HP, and Obermayer-Pietsch B. Long-term and sequential treatment for osteoporosis. Nat Rev Endocrinol 2023; 19:520–533. 
5. Song S, Guo Y, Yang Y, and Fu D. Advances in pathogenesis and therapeutic strategies for osteoporosis. Pharmacol Ther 2022; 237:108168. 
6. Zhang L, Zheng Y-L, Wang R, Wang X-Q, and Zhang H. Exercise for osteoporosis: a literature review of pathology and mechanism. Front Immunol 2022; 13:1005665. 
7. Alyamani M, Alshehri S, Alam P, Wani SUD, Ghoneim MM,  Shakeel F. Solubility and solution thermodynamics of raloxifene hydrochloride in various (DMSO+ water) compositions. Alexandria Eng J 2022; 61:9119–9128. 
8. Kher JD, Sorathia K, and Kher JD. Bioavailability enhancement of BCS class II raloxifene hydrochloride by inclusion complex and solid dispersion techniques. Zhongguo Ying Yong Sheng Li Xue Za Zhi= Zhongguo Yingyong Shenglixue Zazhi= Chinese J Appl Physiol 2024; 40:e20240002. 
9. Jha AK. Methods of improving the solubility and bioavailability of therapeutic agents. United States: Google Patents; US11311493B2, 2025. 
10. Abukhalil A. Raloxifene composition. WIPO (PCT); WO2011000581A2, 2011. 
11. Alagarsamy A, Rambabu B, Reddy PS, Venugopal K, Kumar BR. Raloxifene pharmaceutical formulations. United States; US20110159084A1, 2009. 
12. Williams G, Suman JD. In vitro anatomical models for nasal drug delivery. Pharmaceutics 2022; 14:1353-1364. 
13. Chavda VP, Jogi G, Shah N, Athalye MN, Bamaniya N, Vora LK, et al. Advanced particulate carrier-mediated technologies for nasal drug delivery. J Drug Deliv Sci Technol 2022; 74:103569. 
14. Rai G, Gauba P, Dang S. Recent advances in nanotechnology for Intra-nasal drug delivery and clinical applications. J Drug Deliv Sci Technol 2023; 86:104726. 
15. Rabiee N, Ahmadi S, Afshari R, Khalaji S, Rabiee M, Bagherzadeh M, et al. Polymeric nanoparticles for nasal drug delivery to the brain: relevance to Alzheimer’s disease. Adv Ther 2021; 4:2000076. 
16. Keller L-A, Merkel O, and Popp A. Intranasal drug delivery: Opportunities and toxicologic challenges during drug development. Drug Deliv Transl Res 2022; 12:735–757. 
17. Fortuna A, Schindowski K, and Sonvico F. Intranasal drug delivery: Challenges and opportunities. Front Pharmacol 2022; 13:868986. 
18. Li S, Yang C, Li J, Zhang C, Zhu L, Song Y, et al. Progress in pluronic F127 derivatives for application in wound healing and repair. Int J Nanomedicine 2023; 18: 4485–4505. 
19. Shamma RN, Sayed RH, Madry H, El Sayed NS, and Cucchiarini M. Triblock copolymer bioinks in hydrogel three-dimensional printing for regenerative medicine: A focus on pluronic F127. Tissue Eng Part B Rev 2022; 28:451–463. 
20. Lupu A, Rosca I, Gradinaru VR, and Bercea M. Temperature induced gelation and antimicrobial properties of Pluronic F127 based systems. Polymers (Basel) 2023; 15:355-372. 
21. Varshosaz J, Minaiyan M, and Dayyani L. Poly(methyl vinyl ether-co-maleic acid) for enhancement of solubility, oral bioavailability and anti-osteoporotic effects of raloxifene hydrochloride. Eur J Pharm Sci 2018; 112:195–206. 
22. Kim EY, Gao ZG, Park JS, Li H, Han K. rhEGF/HP-beta-CD complex in poloxamer gel for ophthalmic delivery. Int J Pharm 2002; 233:159–167. 
23. Qian L, Cook MT, Dreiss CA. In situ gels for nasal delivery: Formulation, characterization and applications. Macromol Mater Eng 2025; 2400356. 
24. Suhagiya K, Borkhataria CH, Gohil S, Manek RA, Patel KA, Patel NK, et al. Development of mucoadhesive in-situ nasal gel formulation for enhanced bioavailability and efficacy of rizatriptan in migraine treatment. Results Chem 2023; 6:101010. 
25. Hard SAAA, Shivakumar HN, Bafail DA, and Moqbel Redhwan MA. Development of in vitro and in vivo evaluation of mucoadhesive in-situ gel for intranasal delivery of vinpocetine. J Drug Target 2025; 33:528–545. 
26. El-Shenawy AA, Mahmoud RA, Mahmoud EA, Mohamed MS. Intranasal in situ gel of apixaban-loaded nanoethosomes: Preparation, optimization, and in vivo evaluation. AAPS PharmSciTech 2021; 22:147. doi: 10.1208/s12249-021-02020-y.
27. Mali A, Bhanwase A. In vitro, Ex vivo and in vivo assessment of brain targeted thermoreversible mucoadhesive in situ intranasal gel of carmustine for the treatment of glioblastoma. Bionanoscience 2024; 14:2571–2581. 
28. Shah N V, Seth AK, Balaraman R, Aundhia CJ, Maheshwari RA, Parmar GR. Nanostructured lipid carriers for oral bioavailability enhancement of raloxifene:  Design and in vivo study. J Adv Res 2016; 7:423–434. 
29. Tjahjono R and Singh N. Correlation between nasal mucosal temperature change and the perception of nasal patency: A literature review. J Laryngol Otol 2021; 135:104–109. 
30. Zhou Y, Zhang X-L, Lu S-T, Zhang N-Y, Zhang H-J, Zhang J, et al. Human adipose-derived mesenchymal stem cells-derived exosomes encapsulated in pluronic F127 hydrogel promote wound healing and regeneration. Stem Cell Res Ther 2022; 13:407-423. 
31. Wu T-Y, Huang C-C, Tsai H-C, Lin T-K, Chen P-Y, Darge HF, et al. Mucin-mediated mucosal retention via end-terminal modified Pluronic F127-based hydrogel to increase drug accumulation in the lungs. Biomater Adv 2024; 156:213722. 
32. Morsi N, Ghorab D, Refai H, and Teba H. Ketoroloac tromethamine loaded nanodispersion incorporated into thermosensitive  in situ gel for prolonged ocular delivery. Int J Pharm 2016; 506:57–67. 
33. Sherafudeen SP and Vasantha PV. Development and evaluation of in situ nasal gel formulations of loratadine. Res Pharm Sci 2015; 10:466–476. 
34. Srivastava SK, Prasad M, Jha AK. Development and Evaluation of Thermo Triggered in situ nasal gel of selegiline for depressive disorders: In vitro, in vivo and ex vivo characterization. Res J Pharm Technol 2022; 15:1424–1430. 
35. Garc\’\ia-Couce J, Tomás M, Fuentes G, Que I, Almirall A, Cruz LJ. Chitosan/Pluronic F127 thermosensitive hydrogel as an injectable dexamethasone delivery carrier. Gels 2022; 8:44-59. 
36. Nian X, Zhang J, Huang S, Duan K, Li X, Yang X. Development of nasal vaccines and the associated challenges. Pharmaceutics 2022; 14:1983-2008. 
37. Mali AH, Shaikh AZ. A short review on nasal drug delivery system. Asian J Pharm Technol 2021; 11:289–292. 
38. Amponsah SK and Adams I. Drug Absorption via the Nasal Route: Opportunities and Challenges. In: Nasal Drug Delivery, Formulations, Developments, Challenges, and Solutions, Springer International Publishing, 2023; 25–42.
39. Mankar SD, Parjane SR, Siddheshwar SS, Dighe SB. Formulation, optimization and in vivo characterization of thermosensitive in situ nasal gel loaded with bacoside a for treatment of epilepsy. AAPS PharmSciTech 2024; 25:151. doi: 10.1208/s12249-024-02870-2.
40. Kammoun AK, Khedr A, Hegazy MA, Almalki AJ, Hosny KM, Abualsunun WA, et al. Formulation, optimization, and nephrotoxicity evaluation of an antifungal in situ nasal gel loaded with voriconazole--clove oil transferosomal nanoparticles. Drug Deliv 2021; 28:2229–2240. 
41. Balakrishnan P, Park E-K, Song C-K, Ko H-J, Hahn T-W, Song K-W, et al. Carbopol-incorporated thermoreversible gel for intranasal drug delivery. Molecules 2015; 20:4124–4135. 
42. dos Santos ACM, Akkari ACS, Ferreira IRS, Maruyama CR, Pascoli M, Guilherme VA, et al. Poloxamer-based binary hydrogels for delivering tramadol hydrochloride: sol-gel  transition studies, dissolution-release kinetics, in vitro toxicity, and pharmacological evaluation. Int J Nanomedicine 2015; 10:2391–2401. 
43. Şenyiğit ZA, Karavana SY, İlem-Özdemir D, Çalışkan Ç, Waldner C, Şen S, et al. Design and evaluation of an intravesical delivery system for superficial bladder  cancer: Preparation of gemcitabine HCl-loaded chitosan-thioglycolic acid nanoparticles and comparison of chitosan/poloxamer gels as carriers. Int J Nanomedicine 2015; 10:6493–6507. 
44. Bhandwalkar MJ and Avachat AM. Thermoreversible nasal in situ gel of venlafaxine hydrochloride: Formulation,  characterization, and pharmacodynamic evaluation. AAPS PharmSciTech 2013; 14:101–110. 
45. Kushan E and Senses E. Thermoresponsive and injectable composite hydrogels of cellulose nanocrystals and pluronic F127. ACS Appl Bio Mater 2021; 4:3507–3517. 
46. Zou S, He Q, Wang Q, Wang B, Liu G, Zhang F, et al. Injectable nanosponge-loaded Pluronic F127 hydrogel for pore-forming toxin neutralization. Int J Nanomedicine 2021; 4239–4250. 
47. Yurtda\cs-K\ir\iml\io\uglu G. A promising approach to design thermosensitive in situ gel based on solid dispersions of desloratadine with Kolliphor®188 and Pluronic®F127. J Therm Anal Calorim 2022; 147:1307–1327. 
48. Rao M, Agrawal DK, and Shirsath C. Thermoreversible mucoadhesive in situ nasal gel for treatment of Parkinson’s  disease. Drug Dev Ind Pharm 2017; 43:142–150. 
49. Verhoeven E, Vervaet C, and Remon JP. Xanthan gum to tailor drug release of sustained-release ethylcellulose mini-matrices prepared via hot-melt extrusion: In vitro and in vivo evaluation. Eur J Pharm Biopharm 2006; 63:320–330. 
50. Charoo NA, Kohli K, Ali A. Preparation of in situ-forming ophthalmic gels of ciprofloxacin hydrochloride for  the treatment of bacterial conjunctivitis: In vitro and in vivo studies. J Pharm Sci 2003; 92:407–413. 
51. Mahmoud RA, Abdelhafez WA, Mahmoud EA, Hassan Y, Amin MA, Zayed GM, et al. Cilostazol niosomes-loaded transdermal gels: An in vitro and in vivo anti-aggregant and skin permeation activity investigations towards preparing an efficient nanoscale formulation. Nanotechnol Rev 2024; 13:20240066. 
52. Bosman A, Koek WNH, Campos-Obando N, van der Eerden BCJ, Ikram MA, Uitterlinden AG, et al. Sexual dimorphisms in serum calcium and phosphate concentrations in the Rotterdam  Study. Sci Rep 2023; 13:8310-8319. 
53. Pardhe BD, Pathak S, Bhetwal A, Ghimire S, Shakya S, Khanal PR, et al. Effect of age and estrogen on biochemical markers of bone turnover in  postmenopausal women: A population-based study from Nepal. Int J Womens Health 2017; 9:781–788. 
54. Shu J, Tan A, Li Y, Huang H, and Yang J. The correlation between serum total alkaline phosphatase and bone mineral density  in young adults. BMC Musculoskelet Disord 2022; 23:467-474. 
55. Cheng X and Zhao C. The correlation between serum levels of alkaline phosphatase and bone mineral  density in adults aged 20 to 59 years. Medicine (Baltimore) 2023; 102:e34755. 
56. Ahmed OA and Badr-Eldin SM. In situ misemgel as a multifunctional dual-absorption platform for nasal delivery  of raloxifene hydrochloride: Formulation, characterization, and in vivo performance. Int J Nanomedicine 2018; 13:6325–6335. 
57. Saini D, Fazil M, Ali MM, Baboota S, and Ali J. Formulation, development and optimization of raloxifene-loaded chitosan  nanoparticles for treatment of osteoporosis. Drug Deliv 2015; 22:823–836. 
58. Moreno E, Schwartz J, Larrañeta E, Nguewa P, Sanmartín C, Agüeros M, et al. Thermosensitive hydrogels of poly(methyl vinyl ether-co-maleic anhydride) - Pluronic (R) F127 copolymers for controlled protein release. Int J Pharm 2014; 459:1-9. 
59. Varshosaz J, Hassanzadeh F, Sadeghi-aliabadi H, Larian Z, Rostami M. Synthesis of Pluronic® F127-poly (methyl vinyl ether-alt-maleic acid) copolymer and production of its micelles for doxorubicin delivery in breast cancer. Chem Eng J 2014; 240:133–146.