Browsing by Subject "High glucose"

Now showing 1 - 4 of 4
  • Thumbnail Image
    Publication
    Open Access
    1,25-Dihydroxyvitamin D3 mitigates high glucose-induced oxidative stress, inflammation, and extracellular matrix accumulation in glomerular mesangial cells via the ROS/TXNIP/NLRP3 pathway
    (2026) Bo Chen; Chunjiang Zhang; Lin Jia; Xingyu Yao; Gang Liu; Qingyue Meng; Biología Celular e Histología; Universidad de Murcia, Departamento de Biologia Celular e Histiologia
    ackground. 1,25-Dihydroxyvitamin D3 (1,25(OH)2D3) is a physiologically active form of vitamin D. Our study investigated the renoprotective functions of 1,25(OH)2D3 in diabetic nephropathy (DN) progression and its underlying mechanism targeting the ROS/TXNIP/NLRP3 inflammasome pathway. Methods. DN was induced in Wistar rats via high-fat diet (4 weeks) and streptozotocin injection (30 mg/kg, i.p.); hyperglycemic rats were randomized into DN and DN + 1,25(OH)2D3 (16 μg/kg, 12 weeks) groups. Rat mesangial HBZY-1 cells were maintained under normal glucose (5.5 mM), high glucose (25 mM), high glucose plus 1,25(OH)2D3 (1-50 nM), or high glucose plus N acetylcysteine (NAC, 10 mM). Cell viability was assessed by the CCK-8 assay. Oxidative stress parameters (ROS via DCFH-DA fluorescence, MDA content, SOD activity) and pyroptosis markers (LDH release, PI/Hoechst 33342 nuclear staining) were quantified. Renal histopathology was performed using PAS and Masson trichrome staining. Biochemical analyses included serum creatinine, urea nitrogen, and 24h urinary protein quantification. Molecular profiling encompassed ELISA (IL-1β, IL-6, TNF-α, IL-18, fibronectin, collagen IV), RT-qPCR (NOX2, NOX4, NLRP3, ASC), western blotting (TXNIP, NLRP3, ASC, caspase-1, IL-1β, IL-18, collagen IV, fibronectin, laminin), and TXNIP immunofluorescence. Results. 1,25(OH)2D3 significantly attenuated high glucose-induced pathological alterations in HBZY-1 cells, including ROS overproduction, TXNIP upregulation, NLRP3 inflammasome activation, oxidative stress, inflammation, extracellular matrix (ECM) deposition, and pyroptotic cell death. Consistently, 1,25(OH)2D3 suppressed ROS/TXNIP/ NLRP3/caspase-1 signaling, ameliorated renal dysfunction, and mitigated histopathological damage in DN rats. Conclusion. 1,25(OH)2D3 confers renoprotection in DN by inhibiting the ROS/TXNIP/NLRP3 inflamma some axis, thereby suppressing oxidative stress, inflammatory cytokine production, ECM accumulation, and pyroptotic cell death in glomerular mesangial cells and renal tissues.
  • Thumbnail Image
    Publication
    Open Access
    Death-associated protein kinase 1 correlates with podocyte apoptosis and renal damage and can be mediated by miR-361
    (Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2021) Wu, Guang-jun; Zhao, Hong-biao; Zhang, Xiao-wei
    Background. Herein, we aimed to determine whether DAPK1 and its post-transcriptional regulator miR-361 were implicated in high glucose (HG)-induced podocyte injury and renal damage in db/db mice. Materials and methods. Podocytes were incubated with normal glucose (NG; 5 mM) or HG (30 mM). Podocyte apoptosis was evaluated using TUNEL staining. Lentiviral-delivered specific short hairpin RNA (shRNA) was designed to silence DAPK1 expression in podocytes. miR-361 agomir was administrated by tail intravenous injection in db/db diabetic mice to investigate the renoprotection of miR-361 in vivo. Results. Exposure of podocytes to HG led to a significant increase in DAPK1 mRNA and protein levels and a decrease in miR-361 expression levels. Knockdown of DAPK1 attenuated HG-triggered growth inhibition, apoptosis, DNA damage and cell membrane damage in podocytes. Mechanically, DAPK1 was a direct target of miR-361. Transfection with miR-361 mimics into podocytes resulted in a significant decrease in the DAPK1 protein expression level. In addition, HGinduced the up-regulation of the DAPK1 protein expression level in podocytes was restrained by miR-361 mimics transfection. Intriguingly, overexpression of DAPK1 in HG-stimulated podocytes muted miR-361- mediated cytoprotection, including anti-apoptosis, resistance to DNA and membrane damage. In vivo, overexpression of miR-361 protected against hyperglycemia-induced podocyte loss, tubular atrophy and interstitial fibrosis in the kidney of db/db mice. Moreover, overexpression of miR-361 inhibited the protein expression of DAPK1 in the kidney of db/db mice. Conclusion. Our research presented a novel mechanism of HG-induced podocyte damage or renal lesion, supporting the miR-361/DAPK1 signaling pathway that could be used as a potential therapeutic target for the treatment of DN.
  • Thumbnail Image
    Publication
    Open Access
    Electron microscopic analysis of glucose-induced endothelial damage in primary culture: Possible mechanism and prevention
    (Murcia : F. Hernández, 2006) Mandal, A.K.; Ping, T.; Caldwell, S.; Bagnell, R.; Hiebert, L.M.
    We previously reported that high glucose treated cultured endothelial cells (ECs) showed intercellular gaps by transmission electron microscopy (TEM). These gaps were abrogated with insulin and/or heparin treatment. Our aims were to assess the severity of injury in ECs treated with high glucose for variable duration, and to further study the protective effects of insulin and/or heparin. Cells were also treated with Lbuthionine sulfoximine (BSO), a glutathione inhibitor, to help understand the mechanism of high glucose injury. Primary porcine ECs were treated with high glucose (30 mM) for 2, 6 or 10 days; and glucose plus insulin (1 U/ml), glucose plus heparin (5 µg/ml), glucose plus insulin plus heparin for 6 days. ECs were treated with BSO (0.001-0.05 mM) for 2 days. Pellets from trypsinized cells were processed for TEM. High glucose treatment revealed apoptosis or necrosis showing variable cell size, abnormal nuclei, condensation of nuclear chromatin, few mitochondria, cell membrane disruption and needle-shaped structures. Changes increased with duration of exposure. In high glucose plus heparin or insulin treated cultures at least one-half of the cells appeared normal. Most ECs were intact when treated with high glucose plus insulin plus heparin. BSO treatment showed dose-dependent changes with low doses showing apoptosis whereas higher doses revealed necrosis similar to high glucose treatment for 6 or 10 days. High glucose-induced EC injury increased with duration of exposure. These data demonstrate that high glucose injury resembles that of BSO treatment, suggesting that glutathione depletion may be involved in EC injury. Insulin and/or heparin protect against high glucose-induced injury.
  • Thumbnail Image
    Item
    Open Access
    Lysophosphatidylcholine negatively reverses the effects of human umbilical cord-derived mesenchymal stem cells on high glucose-induced cell dysfunction
    (Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2026) Yong Chai; Han Liu; Yao Zhao; ChunYi Liu; Rui Luo; Qiang Gan; Xian Liu; Biología Celular e Histología
    Background. Increasing attention has been attracted to the application of human umbilical cord-derived mesenchymal stem cells (HUCMSCs) in the cell therapy of various diabetic complications, including diabetic retinopathy (DR). Lysophosphatidylcholine (LPC) has been reported to induce cell apoptosis and an inflammatory response. The present study aimed to investigate the mechanism of HUCMSCs in high glucose (HG)-treated retinal microvascular endothelial cells (RMECs) and the effect of LPC on this mechanism. Methods. To mimic DR in vitro, RMECs were treated with HG. Flow cytometry analysis was used to identify HUCMSCs and the expression of their surface markers. The apoptosis of RMECs was also accessed using flow cytometry analysis. A CCK-8 assay was performed to measure the viability of RMECs. ELISA was used to detect the concentration of inflammatory cytokines (TNF-α, IL-6, and IL-1β) in RMECs. The protein expression of tight junction proteins in RMECs was examined using western blot analysis. Results. HUCMSCs were identified to present positive markers (CD105, CD73, and CD90) and loss of negative markers (CD45, CD34, and HLA-DR). In RMECs, HG significantly induced a decrease in cell viability and an increase in cell apoptosis and tight junction proteins. Moreover, HG treatment promoted the production of inflammatory cytokines (TNF-α, IL-6, and IL-1β) and facilitated oxidative stress. However, these dysregulated cellular behaviors were alleviated by the treatment of the culture medium of HUCMSCs. Furthermore, LPC treatment reversed the effect of HUCMSCs on HG-induced RMEC injury and impaired the blood-retinal barrier. Moreover, the effect of HUCMSCs on the inflammatory response and oxidative stress of RMEC was also neutralized by LPC treatment. Conclusion. LPC reverses the effects of HUCMSCs on HG-induced RMEC dysfunction, impaired blood-retinal barrier, inflammation, and oxidative stress