Magnetic iron-oxide nanoparticles in the brain connected to alcohol-associated liver disease

• Published in: Scientific reports Vol. 15; no. 1; pp. 24505 - 9
• Main Authors: Kaub, Leon, Milz, Stefan, Barapatre, Nirav, Büttner, Andreas, Michalke, Bernhard, Schmitz, Christoph, Gilder, Stuart A.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 08.07.2025; Nature Publishing Group; Nature Portfolio
• Subjects: 631/378; 631/45/321/1155; 639/301/357/997; 639/925/928/1069; 692/4020/4021/1607/1608; Aged; Air pollution; Alcohol; Alcohol use disorder; Alzheimer's disease; Brain - metabolism; Brain - pathology; Brain iron; Brain magnetite; Brain stem; Brain Stem - metabolism; Brain Stem - pathology; Cirrhosis; Copper; Female; Health hazards; Heavy metals; Homeostasis; Humanities and Social Sciences; Humans; Indoor air pollution; Iron - metabolism; Iron overload; Iron oxides; Isotopes; LA-ICP-MS; Liver; Liver cirrhosis; Liver diseases; Liver Diseases, Alcoholic - metabolism; Liver Diseases, Alcoholic - pathology; Magnetic Iron Oxide Nanoparticles - chemistry; Magnetite; Male; Manganese; Mass spectrometry; Mass spectroscopy; Middle Aged; multidisciplinary; Nanoparticles; Neurodegenerative diseases; Physiology; Polymerization; Science; Science (multidisciplinary); Surface charge; Trace metals; Brain iron; Iron overload; LA-ICP-MS; Brain magnetite; Alcohol use disorder
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-025-09756-8

Magnetic iron-oxide nanoparticles in the form of magnetite (Fe 3 O 4 ) are present in the human brain. They have been hypothesized to biomineralize in situ, as a result of dysfunctional iron homeostasis related to Alzheimer’s disease, or to enter the brain as airborne pollution particles. Regardless of their origin, magnetic iron-oxides pose a potential hazard to human health due to their high redox activity and surface charge. Here we report measurements on four post-mortem human brainstems, with one brainstem showing approximately 100 times higher magnetite concentrations than the other cases. This brainstem came from a subject with alcohol-associated liver disease (ALD) that manifested in liver cirrhosis and massive hepatic iron overload. Laser ablation – inductively coupled plasma – mass spectrometry showed the highest levels of trace metals (iron, copper and manganese) in the ALD brainstem. It is well established that a dysfunctional liver can result in the accumulation of trace metals in the brain. Our data indicate a similar pathway for magnetite particles, yet liver pathology has not been linked to magnetite occurrence in the brain so far. It may prove to be a crucial factor in understanding the high variation of magnetite concentrations found in human brains.