Intracellular gap (iGap) formation in liver sinusoidal endothelial cells (LSECs) is caused by the destruction of fenestrae and appears under pathological conditions; nevertheless, their role in metastasis of cancer cells to the liver remained unexplored. We elucidated that hepatotoxin-damaged and fibrotic livers gave rise to LSECs-iGap formation, which was positively correlated with increased numbers of metastatic liver foci after intrasplenic injection of Hepa1-6 cells. Hepa1-6 cells induced interleukin-23–dependent tumor necrosis factor–α (TNF-α) secretion by LSECs and triggered LSECs-iGap formation, toward which their processes protruded to transmigrate into the liver parenchyma. TNF-α triggered depolymerization of F-actin and induced matrix metalloproteinase 9 (MMP9), intracellular adhesion molecule 1, and CXCL expression in LSECs. Blocking MMP9 activity by doxycycline or an MMP2/9 inhibitor eliminated LSECs-iGap formation and attenuated liver metastasis of Hepa1-6 cells. Overall, this study revealed that cancer cells induced LSEC-iGap formation via proinflammatory paracrine mechanisms and proposed MMP9 as a favorable target for blocking cancer cell metastasis to the liver.

Hepatic stellate cells (HSCs) are the primary cell type in liver fibrosis, a significant global health care burden. Cytoglobin (CYGB), a globin family member expressed in HSCs, inhibits HSC activation and reduces collagen production. We studied the antifibrotic properties of globin family members hemoglobin (HB), myoglobin (MB), and neuroglobin (NGB) in comparison with CYGB. We characterized the biological activities of globins in cultured human HSCs (HHSteCs) and their effects on carbon tetrachloride (CCl₄)-induced cirrhosis in mice. All globins demonstrated greater antioxidant capacity than glutathione in cell-free systems. Cellular fractionation revealed endocytosis of extracellular MB, NGB, and CYGB, but not HB; endocytosed globins localized to intracellular membranous, cytoplasmic, and cytoskeletal fractions. MB, NGB, and CYGB, but not HB, scavenged reactive oxygen species generated spontaneously or stimulated by H₂O₂ or transforming growth factor β1 in HHSteCs and reduced collagen 1A1 production via suppressing COL1A1 promoter activity. Disulfide bond-mutant NGB displayed decreased heme and superoxide scavenging activity and reduced collagen inhibitory capacity. RNA sequencing of MB- and NGB-treated HHSteCs revealed downregulation of extracellular matrix–encoding and fibrosis-related genes and HSC deactivation markers. Upregulation of matrix metalloproteinase (MMP)-1 was observed following MB and NGB treatment, and MMP-1 knockdown partially reversed globin-mediated effects on secreted collagen. Importantly, administration of MB, NGB, and CYGB suppressed CCl₄-induced mouse liver fibrosis. These findings revealed unexpected roles for MB and NGB in deactivating HSCs and inhibiting liver fibrosis development, suggesting that globin therapy may represent a new strategy for combating fibrotic liver disease.

Pancreatic cancer is a highly challenging malignancy with extremely poor prognosis. Cytoglobin (CYGB), a hemeprotein involved in liver fibrosis and cancer development, is expressed in pericytes of all organs. Here, we examined the role of CYGB in the development of pancreatic cancer. CYGB expression appeared predominately in the area surrounding adenocarcinoma and negatively correlated with tumor size in patients with pancreatic cancer. Directly injecting 7, 12-dimethylbenz[a]anthracene into the pancreatic tail in wild-type mice resulted in time-dependent induction of severe pancreatitis, fibrosis, and oxidative damage, which was rescued byCygboverexpression in transgenic mice. Pancreatic cancer incidence was 93% in wild-type mice but only 55% in transgenic mice. Enhanced CYGB expression in human pancreatic stellate cells in vitro reduced cellular collagen synthesis, inhibited cell activation, increased expression of antioxidant-related genes, and increased CYGB secretion into the medium.Cygb-overexpressing or recombinant human CYGB (rhCYGB) -treated MIA PaCa-2 cancer cells exhibited dose-dependent cell cycle arrest at the G1 phase, diminished cell migration, and reduction in colony formation. RNA sequencing in rhCYGB-treated MIA PaCa-2 cells revealed downregulation of cell cycle and oxidative phosphorylation pathways. An increase in MIA PaCa-2 cell proliferation and reactive oxygen species production by H₂O₂challenge was blocked by rhCYGB treatment orCygboverexpression. PANC-1, OCUP-A2, and BxPC-3 cancer cells showed similar responses to rhCYGB. Known antioxidants N-acetyl cysteine and glutathione also inhibited cancer cell growth. These results demonstrate that CYGB suppresses pancreatic stellate cell activation, pancreatic fibrosis, and tumor growth, suggesting its potential therapeutic application against pancreatic cancer.

Neuropathic pain (NP) arises from diverse conditions, including peripheral nerve injury, spinal cord injury (SCI), and painful diabetic neuropathy, yet these disorders share oxidative stress, mitochondrial dysfunction, lipid dysregulation, and altered neuronal excitability. We investigated whether dietary omega-3 polyunsaturated fatty acids modulate ferroptotic stress-associated pathways, defined as lipid peroxidation susceptibility and impaired antioxidant defense rather than overt ferroptotic cell death. Female Sprague–Dawley rats received either a soy oil control diet (SOD) or fish oil omega-3-enriched diet (FOD) before chronic constriction injury (CCI). Behavioral outcomes were assessed using Hargreaves and CatWalk testing, followed by dorsal root ganglion (DRG) RNA sequencing, RT-PCR, and GPX4 ELISA. Previously generated SCI metabolomics and human diabetic serum metabolomic/lipidomic datasets were re-analyzed for shared pathways. FOD attenuated CCI-induced thermal hypersensitivity and improved gait parameters. DRG transcriptomics showed reduced injury-associated transcriptional disruption, enrichment of selenoamino acid metabolism, nonsense-mediated decay, and ribosomal quality-control pathways, and reduced mitochondrial dysfunction pathway activity. Omega-3 increased Gpx1/Gpx4 expression and GPX4 protein, reduced pain-associated genes including Scn10a, Piezo2, Trpa1, and Oprm1, and aligned with selenoamino acid enrichment in SCI and human datasets. Human lipidomics showed MG/DG/PC/PE pathway remodeling. These findings support ferroptotic stress as a plausible shared downstream mechanism modulated by omega-3 supplementation across NP models.