Dataset Information

The effects of hyperuricemia on endothelial cells are mediated via GLUT9 and the JAK2/STAT3 pathway.

ABSTRACT:

Background

Uric acid (UA) transporters mediate the uptake and outflow of UA, and are greatly involved in the control of UA concentrations. Glucose transporter 9 (GLUT9), one of the UA transporters, has been confirmed to be expressed in human umbilical vein endothelial cells (HUVECs). This study aimed to characterize GLUT9's effect on intracellular UA accumulation in HUVECs in a high-UA environment and to explore the mechanism of cellular dysfunction.

Methods and results

HUVECs were treated with UA to establish a model of cellular dysfunction. Then, UA uptake, GLUT9 expression and endothelial nitric oxide synthase (eNOS) and reactive oxygen species (ROS) amounts were measured. UA uptake was concentration- and time-dependent, and UA treatment significantly reduced nitric oxide (NO) levels and eNOS activity. UA also upregulated pro-inflammatory molecules and GLUT9, and increased intracellular ROS amounts in HUVECs. GLUT9 knockdown reduced UA uptake and ROS content, but antioxidant treatment did not reduce GLUT9 expression. To assess the function of JAK2/STAT3 signaling, HUVECs were treated with UA, and the phosphorylation levels of JAK2, STAT3, IL-6 and SOCS3 were increased by a high concentration of UA. In addition, GLUT9 knockdown reduced the phosphorylation of JAK2/STAT3 intermediates and increased p-eNOS amounts.

Conclusions

GLUT9 mediated the effects of high UA levels on HUVECs by increasing the cellular uptake of UA, activating JAK2/STAT3 signaling, and reduced the production of active eNOS and NO in HUVECs.

SUBMITTER: Nie Q

PROVIDER: S-EPMC8604859 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Sarcodon imbricatus, a rare medicinal and edible fungus, has various pharmacological bioactivities. We investigated the effects of S. imbricatus polysaccharides (SIPS) on hematopoietic function and identified the underlying mechanisms using in vitro experiments with CHRF, K562, and bone marrow mononuclear cells (BMMNCs) and in vivo experiments with a mouse model of cyclophosphamide-induced hematopoietic dysfunction. We found that SIPS induced proliferation and differentiation of CHRF and K562 cells and upregulated the expression of hematopoietic-related proteins, including p90 ribosomal S6 kinases (RSK1p90), c-Myc, and ETS transcription factor, in the two cell lines. After 28 days of treatment, SIPS enhanced the bodyweight and thymus indices of the mice, alleviated enlargement of the spleen and liver, and contributed to the recovery of peripheral blood to normal levels. More importantly, the percentages of B lymphocytes and hematopoietic stem cells or hematopoietic progenitor cells were significantly elevated in bone marrow. Based on an antibody chip analysis and enzyme-linked immunosorbent assay, SIPS were found to successfully regulate 12 cytokines to healthy levels in serum and spleen. The cytokines included the following: interleukins 1Ra, 2, 3, 4, 5, and 6, tumor necrosis factor α, interferon-γ, granulocyte colony-stimulating factor (G-CSF) and macrophage colony-stimulating factor (M-CSF), C-C motif chemokine1, and monocyte chemoattractant protein-1. Moreover, SIPS upregulated the phosphorylation levels of janus kinase 2 (JAK2) and the signal transducer and activator of transcription 3 (STAT3) in the spleen, and similar results were validated in CHRF cells, K562 cells, and BMMNCs. The data indicate that SIPS activated the JAK2/STAT3 pathway, possibly by interactions among multiple cytokines, particularly G-CSF. We found that SIPS was remarkably beneficial to the bone marrow hematopoietic system, and we anticipate that it could improve myelosuppression induced by long-term radiotherapy or chemotherapy.

Project description:As the current clinical treatment of acetaminophen (APAP)‑induced liver injury (AILI) has its limitations, new and effective treatment methods are required. Fingolimod (FTY720) is an immunosuppressive drug developed in recent years that has been shown to have a protective effect against ischemia/reperfusion liver injury. However, the role of FTY720 in AILI remains unclear. The aim of the present study was to determine whether FTY720 has a protective effect on AILI. AILI was induced using intraperitoneal injection of 300 mg/kg APAP in male C57BL/6J mice. Following APAP challenge, the mice were administered 5 mg/kg FTY720 for 30 min. Protein expression levels were measured using western blot analysis. Cell viability was examined using Cell Counting Kit‑8 assays. mRNA levels were measured using reverse transcription‑quantitative PCR. Inflammation levels were evaluated using immunohistochemistry. Cell death and reactive oxygen species levels were examined using immunofluorescence. Furthermore, laser scanning intravital microscopy was used to directly observe immune cell recruitment. APAP treatment increased the serum levels of alanine transaminase and aspartate transaminase at the 6‑ and 12‑h time‑points, suggesting liver tissue damage. However, FTY720 attenuated the liver injury induced by APAP by reducing the recruitment of immune cells and the release of pro‑inflammatory cytokines and chemokines. FTY720 activated JAK2/STAT3 signaling and regulated the expression of BAX, BCL‑2 and p65 to inhibit apoptosis and inflammation. In addition, compared with APAP treatment, the viability of primary hepatocytes treated with APAP and FTY720 was increased. Inhibition of JAK2/STAT3 signaling attenuated the protective, antioxidant effects of FTY720. In conclusion, FTY720 reduced liver injury by regulating the JAK2/STAT3 signaling pathway. This compound was capable of inhibiting oxidative stress to reduce hepatocyte death and the infiltration of neutrophils in the liver.