Search bioRxiv⌕ Search

bioRxiv · 10.1101/2025.07.02.662898

The Ins and Outs of Manganese: ZIP14 facilitates the efflux of excess manganese from the brain.

Abstract

Manganese (Mn) is essential for many enzymatic processes in the brain; however, Mn overload can lead to neurotoxicity and behavioral deficits. The blood-brain barrier (BBB), comprised of polarized endothelial cells, tightly regulates metals in and out of the brain. ZIP14 (SLC39A14) is a metal transporter more recently found to transport Mn, with mutations in human SLC39A14 resulting in brain Mn accumulation and neurological deficits. However, ZIP14s precise localization and role in BBB endothelial cells remain unclear. Here, we show in vivo ZIP14 expression in BBB endothelial cells, which upregulates following Mn supplementation. Using expansion microscopy, we observed a shift in ZIP14 localization from an equal apical-basolateral distribution to predominantly basolateral after Mn exposure. Endothelial-specific Zip14 KO (EKO) mice exhibited impaired Mn efflux from the brain and increased brain Mn accumulation after nasal delivery and dietary Mn supplementation. In vitro studies using primary endothelial cells from EKO mice and ZIP14-overexpressing hCMEC/D3 cells confirmed that ZIP14 primarily mediates basolateral-to-apical Mn transport. Collectively, our results demonstrate that ZIP14 is critical for brain Mn clearance, highlighting its potential as a therapeutic target to mitigate Mn-induced neurotoxicity. Significance StatementOur study reveals that the endothelial metal transporter ZIP14 plays a critical role in removing excess Mn from the brain. Using expansion microscopy, genetic manipulation, metallomics, and transport studies employing radiolabeled Mn, we demonstrate that ZIP14 undergoes strategic relocalization in response to Mn exposure and primarily functions in basolateral-to-apical transport. Deletion of endothelial ZIP14 leads to brain Mn accumulation, establishing its fundamental role in protecting against Mn-induced neurotoxicity. This finding provides mechanistic insight into how the brain protects itself against Mn overload and why ZIP14 mutations in humans result in brain Mn accumulation.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Zou, J., Thorn, T. L., Wang, Z., Wang, Y., Aydemir, T. B.. 2025-07-03. The Ins and Outs of Manganese: ZIP14 facilitates the efflux of excess manganese from the brain.. https://doi.org/10.1101/2025.07.02.662898

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Thoracoabdominal pressure transmission during prone and supine cardiopulmonary resuscitation in fresh-frozen human cadavers

Background: Prone cardiopulmonary resuscitation (CPR) may be necessary when turning a prone patient supine would delay chest compressions. Although prone compressions can generate arterial pressures comparable with or greater than supine CPR, the pathway of pressure transmission is uncertain. We examined synchronized intrathoracic, intra-abdominal, and central arterial pressures in both supine and prone positions. Methods: Two thawed fresh-frozen adult cadavers underwent three, 2-minute mechanical CPR trials per position in a counterbalanced crossover sequence. Solid-state catheters recorded pleural, peritoneal, and central arterial pressures simultaneously. Trial-level outcomes included peak pressure, mean pressure, pressure-time area, and the mean peritoneal-to-pleural pressure gradient. Exploratory fixed-effects models included position, cadaver, and their interaction. Results: Prone CPR increased peak intrathoracic pressure by 7.04 mmHg, peak intra-abdominal pressure by 21.69 mmHg, and peak arterial pressure by 15.40 mmHg. Mean intra-abdominal and arterial pressures increased by 16.22 and 9.90 mmHg, respectively. The mean peritoneal-to-pleural gradient reversed direction from -8.46 mmHg supine to 4.85 mmHg prone. Intrathoracic pressure-time area increased 3.4-fold, from 1.62 to 5.46 mmHg{middle dot}s, and arterial pressure-time area increased 2.2-fold, from 2.96 to 6.42 mmHg{middle dot}s. Conclusions: Compared to supine, prone mechanical CPR generated higher arterial pressures and reversed the pressure relationship across the thoracoabdominal boundary in both cadavers. Higher abdominal pressure coincided with a larger intrathoracic pressure-time area, a pattern compatible with reduced caudal pressure dissipation.

physiology↗

Hypothalamic Farnesoid X Receptor deficiency alters energy balance by modulating hepatic glucose production and adipose tissue metabolism through central insulin signaling.

Objectives: The bile acid nuclear receptor Farnesoid X Receptor (FXR, NR1H4) is a major regulator of metabolism and energy homeostasis in peripheral organs. It modulates bile acid, glucose, and lipid metabolism, as well as fat mass and body weight. However, FXR is also expressed in the brain, particularly in the hypothalamus, a key center for the regulation of energy homeostasis. Although one study has demonstrated a role for brain FXR activation in energy balance, its specific hypothalamic role is still unknown. Here, we examined the role of FXR in the mediobasal hypothalamus in the regulation of energy balance. Methods: We used a genetic approach combined with metabolic phenotyping to determine the effect of FXR invalidation in the mediobasal hypothalamus on metabolic parameters involved in the central regulation of energy homeostasis. Results: Our results demonstrate that hypothalamic FXR deficiency induces a positive energy balance, resulting in a reduction in energy expenditure due to alterations in glucose metabolism accompanied by structural changes in white adipose tissues. Conclusion: This study uncovers a previously unrecognized role for hypothalamic FXR in the central homeostatic control of energy balance, providing new insights into its contribution to peripheral glucose metabolism and adipose tissue structural remodeling.

physiology↗

Rad and Phospholamban are Key Drivers of the Ventricular Adrenergic Response and Stress-Induced Arrhythmia

The adrenergic response is a fundamental mechanism that regulates heart rate (chronotropy), cardiac contractility (inotropy) and relaxation (lusitropy). Adrenergic stress is also a recognized trigger of arrhythmia in disease. Yet, our understanding of the underlying molecular basis remains incomplete. Protein kinase A (PKA) and the calcium/calmodulin-dependent kinase II (CaMKII) phosphorylate multiple targets proposed to participate in the adrenergic response, including the GTP-binding protein Rad, phospholamban (PLB) and ryanodine receptor 2 (RyR2). Here we demonstrate that phosphorylation of both Rad and PLB is necessary for inotropy and lusitropy. We show that changes in cardiac contractility and relaxation are primarily dependent on intracellular calcium handling. Finally, we report that Rad and PLB control stress-induced arrhythmogenesis, despite the phosphorylation of other pro-arrhythmic targets. We have identified the essential molecular components of the adrenergic response, resolving a long-standing debate in cardiac excitation-contraction coupling and refining current models of sympathetic regulation in health and disease.

physiology↗