Conclusion
TNFRII and IKKβ antagonists may improve glucose uptake in granulosa cells induced by TNF-α by blocking the TNFRII-IKKβ-NF-κB signaling pathway under high androgen conditions.
Methods
KGN cell line was treated with testosterone and TNF-α alone or co-culture combination for 24 hr, or starved for 24 hr. Quantitative real-time polymerase chain reaction (qPCR) and western blot were performed to measure glucose transporter type 4 (GLUT4) message RNA (mRNA) and protein expression in treated KGN cells. Glucose uptake and GLUT4 expression were detected by immunofluorescence (IF). Furthermore, western blot was performed to measure the contents in the nuclear factor kappa-B (NF-κB) pathway. Meantime, upon addition of TNF-α receptor II (TNFRII) inhibitor or Inhibitor of nuclear factor kappa-B kinase subunit beta (IKKβ) antagonist to block the TNFRII-IKKβ-NF-κB signaling pathway, the glucose uptake in KGN cells and GLUT4 translocation to cytomembrane were detected by IF, and related proteins in TNFRII-IKKβ-NF-κB were detected by western blot.
Results
The glucose uptake in Testosterone + TNF-α group was lowered significantly, and Total GLUT4 mRNA and proteins were reduced significantly. GLUT4 translocation to cytomembrane was tarnished visibly; concurrently, the phosphorylated proteins in the TNFRII-IKKβ-NF-κB signaling pathway were enhanced significantly. Furthermore, upon addition of TNFRII inhibitor or IKKβ inhibitor to block the TNFRII-IKKβ-NF-κB signaling pathway, the glucose uptake of treated granulosa cells was improved.