Potential water-soluble metal phthalocyanine candidates for the treatment of Alzheimer's disease: Synthesis, cholinesterase enzyme inhibition, kinetic analysis and cytotoxicity against human neuroblastoma (SH-SY5Y)

J Inorg Biochem. 2026 Mar:276:113197. doi: 10.1016/j.jinorgbio.2025.113197. Epub 2025 Dec 15.

Abstract

In this study, manganese (III), cobalt (II), copper (II) and zinc (II) phthalocyanines and their quaternized cationic derivatives bearing morpholine groups in the non-peripheral position were producedand characterized by various spectroscopic techniques such as UV-Vis, FT-IR, 1H and 13C NMR (only for Zn(II)), MALDI-TOF mass spectra. The inhibitory potential of new compounds on AChE and BuChE enzymes was investigated and IC50 values were determined. It was found that water-soluble derivatives showed stronger inhibitory properties. The most effective compounds in AChE inhibition were water-soluble zinc (II) phthalocyanine (ZT6Q) (IC50 = 0.85 ± 0.18 μM) and water-soluble manganese (III) phthalocyanine ZT3Q (IC50 = 2.26 ± 0.38 μM), while ZT6Q showed the strongest effect in BuChE inhibition (IC50 = 5.15 ± 0.48 μM). Lineweaver-Burk analyses revealed that these compounds inhibited both enzymes in a mixed manner. Ki and Kii values were also calculated. In cell viability tests against human neuroblastoma (SH-SY5Y), ZT6Q did not show cytotoxic effects up to 10 μM, on the contrary, they increased cell viability. However, ZT3Q exhibited higher cytotoxicity at 48 h exposure. The findings indicate that these compounds can be evaluated as potential therapeutic agents.

Keywords: Alzheimer; Cholinesterase enzymes; Cytotoxicity; Water-soluble phthalocyanines.

MeSH terms

  • Acetylcholinesterase / chemistry
  • Acetylcholinesterase / metabolism
  • Alzheimer Disease* / drug therapy
  • Alzheimer Disease* / enzymology
  • Butyrylcholinesterase / chemistry
  • Butyrylcholinesterase / metabolism
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Cholinesterase Inhibitors* / chemical synthesis
  • Cholinesterase Inhibitors* / chemistry
  • Cholinesterase Inhibitors* / pharmacology
  • Humans
  • Indoles* / chemical synthesis
  • Indoles* / chemistry
  • Indoles* / pharmacology
  • Isoindoles
  • Kinetics
  • Neuroblastoma* / drug therapy
  • Neuroblastoma* / pathology
  • Solubility
  • Water / chemistry

Substances

  • Indoles
  • Cholinesterase Inhibitors
  • Isoindoles
  • Acetylcholinesterase
  • phthalocyanine
  • Butyrylcholinesterase
  • Water