Hyaluronate functionalized Span-Labrasol nanovesicular transdermal therapeutic system of ferulic acid targeting diabetic nephropathy.

Diabetic kidney disease, known as diabetic nephropathy (DN), is a widespread severe diabetes complication leading to kidney failure. Due to the lack of efficacious therapies, this study endeavors to enhance DN therapeutic effectiveness of ferulic acid (FRA), a natural phenolic with poor oral bioavailability, by developing a transdermal kidney-targeted spanlastic formulation. Spanlastics (SP) nanovesicles were prepared using Span 60 and Labrasol or Brij35 as edge activators (EA). Cationic guar (CG) and hyaluronic acid (HA) were employed as coatings. The formulations were assessed for entrapment efficiency (EE), particle size (PS) and zeta potential (ZP). A 21 × 31 factorial optimization of FRA spanlastic formulations revealed the desirable nanoformula was FRA-L-H-SP comprising Labrasol and hyaluronate coating. Transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR), Diphenylpicrylhydrazyl (DPPH) antioxidant activity, in-vitro release, and rat skin ex-vivo permeation assessed this formula and the uncoated one (FRA-L-SP). Biochemical indicators and histopathology for diabetes and kidney injury were evaluated in the Streptozotocin (STZ)-induced DN rat model. Results showed significant improvements after treatment with FRA-L-H-SP compared to FRA-L-SP and free FRA, with decreased blood glucose, creatinine, and intercellular adhesion molecule-1 (ICAM-1) levels and increased insulin, AMP-activated protein kinase (AMPK), and sirtuins (SIRT). This enhancement can be acknowledged as passive targeting of SP and active targeting properties of hyaluronic to cluster of differentiation 44 (CD44) receptors, revealing the potential to improve DN pathophysiology.