Lithium chloride suppresses ferroptosis of induced pluripotent stem cells with ApoE4/E4 from a sporadic Alzheimer's disease patient

Abstract

Alzheimer's disease (AD), particularly its sporadic form (SAD, 95 % AD patients), is strongly associated with the apolipoprotein E4 (ApoE4) genotype and characterized by oxidative stress, iron dysregulation, and increased susceptibility to ferroptosis. Lithium, a well-established neuroprotective agent, has shown potential to mitigate several pathological mechanisms in AD, including ferroptosis. This study investigates the therapeutic potential of lithium chloride in human induced pluripotent stem cells (iPSCs) derived from a SAD patient with ApoE4/E4 genotype and compared effects with those of isogenic gene-edited ApoE3/E3 control. Lithium treatment significantly improved cell viability in ApoE4/E4 iPSCs. It also reversed key ferroptosis phenotypes, including elevated cytosolic Fe²⁺, increased expression of divalent metal transporter 1, reduced level of glutathione peroxidase 4, enhanced lipid peroxidation and excessive ROS production. Moreover, lithium (0.25 mM) normalized mitochondrial respiration and reduced proton leak, indicating preservation of mitochondrial function and protection against mitochondrial damage and cell death. Lithium also reduced the expression of type 1 InsP₃ receptor (InsP₃R-1) protein, a Ca²⁺ channel located on the endoplasmic reticulum (ER) membrane. Together, these findings highlight lithium's inhibition of ferroptosis through modulation of iron metabolism, antioxidant defenses and inhibition of disrupted Ca²⁺ signaling. Given the drug's demonstrated efficacy in reversing ApoE4-driven cellular vulnerabilities, lithium salt warrants further investigation for the treatment of AD.

Keywords: Calcium; Cell death; Endoplasmic reticulum; Mitochondria; Neurodegenerative diseases; Oxidative stress.