Role of folate-conjugated glycol-chitosan nanoparticles in modulating the activated macrophages to ameliorate inflammatory arthritis: in vitro and in vivo activities

Drug Deliv Transl Res. 2020 Aug;10(4):1057-1075. doi: 10.1007/s13346-020-00765-w.

Abstract

Activated macrophages are the primary targets in rheumatoid arthritis (RA) management. So, we report efficacious, dual-functional Methotrexate (MTX) loaded folate-conjugated pH-responsive glycol-chitosan nanoparticles (MFGCN) prepared by nano-precipitation and zero-order cross-linking reaction for targeting inflamed arthritic tissue. Physical characterization by DLS, SEM and TEM indicated a spherical, smooth morphology with a diameter ~ 300 nm. 1H NMR and FTIR indicated folic acid conjugation to GC by zero-order cross-linkers. In vitro release kinetics in PBS showed pH-responsive and sustained release behaviour of MFGCN. Enhanced cellular uptake and cytotoxicity of MFGCN in LPS(+)RAW and activated peritoneal macrophages (Mϕ) were observed when compared to LPS(-)RAW cells. MFGCN-induced mitochondrial membrane potential (MMP) perturbations indicated apoptosis. Oxidative stress was evident by significant increase in ROS and RNS, 4 h post incubation with MFGCN. Negligible hemolysis by FGCN and MFGCN on rat RBC's indicated biocompatibility. In vivo biodistribution of MFGCN in adjuvant-induced arthritis (AIA) rats indicated RA targetability. Prolonged blood circulation coupled with higher concentrations of 99mTc-MFGCN at the arthritic site was observed post 24 h of injection. The gamma scintigraphic image confirmed accumulation of radiolabelled MFGCN in arthritic paw when compared to the non-inflamed paw, confirming the selective uptake of 99mTc-MFGCN by folate-overexpressing macrophages in the arthritic synovium thereby proving its targeted efficacy and theranostic potential. In AIA rats, MFGCN lowers arthritic signs, improves antioxidant response and decreases pro-inflammatory cytokines, suggesting its potential in targeting activated macrophages of synovium. Graphical abstract.

Keywords: Adjuvant-induced arthritis; Biodistribution; Biopolymers; Glycol chitosan; Methotrexate; Rheumatoid arthritis; Scintigraphy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antirheumatic Agents / administration & dosage*
  • Arthritis, Experimental / drug therapy*
  • Arthritis, Rheumatoid / drug therapy*
  • Cell Survival / drug effects
  • Chitosan / administration & dosage*
  • Chitosan / chemistry
  • Drug Liberation
  • Female
  • Folic Acid / administration & dosage*
  • Folic Acid / chemistry
  • HEK293 Cells
  • Humans
  • MCF-7 Cells
  • Membrane Potential, Mitochondrial / drug effects
  • Methotrexate / administration & dosage*
  • Methotrexate / chemistry
  • Mice
  • Nanoparticles / administration & dosage*
  • Nanoparticles / chemistry
  • RAW 264.7 Cells
  • Rats, Wistar

Substances

  • Antirheumatic Agents
  • glycol-chitosan
  • Chitosan
  • Folic Acid
  • Methotrexate