548-P: Baicalin Attenuates Fibrosis Process in Human Renal Proximal Tubular Cells in Hyperglycemic Condition

Abstract

Background: Baicalin, isolated from Scutellaria baicalensis, has been reported to have anti-inflammatory effect by inhibiting expression of cell adhesion molecules and migration of leukocytes in vascular cells. However, there is a limited evidence on its anti-inflammatory effect in hyperglycemia-associated milieu in other cells. Hyperglycemia and its associated factors are known to induce diabetic nephropathy by exacerbating inflammation, especially, in proximal convoluted tubule. Herein, we investigated whether baicalin exerts anti-inflammatory and anti-fibrosis effects on human renal proximal tubular cells in hyperglycemia induced conditions. Method: HK-2 cell was maintained in normal glycemic (5.78mM glucose) or in hyperglycemic (30mM glucose) condition with or without advanced glycation end-products (AGE) and tumor necrosis factor alpha (TNFα). In each condition, baicalin was treated at 10uM. Cell viability was determined by MTT assay. Gene and protein expression of multiple inflammatory and fibrosis markers including toll-like receptor 2 (TLR2), TLR4, fibronectin, collagen IV α1 (ColIVα1), collagen IV α2 (ColIVα2), transforming growth factor β (TGFβ), intercellular adhesion molecule 1 (ICAM1), and vascular adhesion molecule 1 (VCAM1) were evaluated by PCR and WB, respectively. Results: Baicalin had no effect on cell viability. Baicalin significantly decreased gene expression of ColIVα2 in response to TNFα stimulation in normal glycemic condition (p=0.038). In hyperglycemic condition, baicalin decreased gene expressions of ICAM1 (p=0.049) and VCAM1 (p=0.049) significantly in AGE treated cells; and it significantly decreased gene expressions of TGFβ (p=0.038) and ICAM1 (p=0.017) in TNFα treated cells. Baicalin also decreased protein expression of ICAM1 in response to AGE (p=0.048) and TNFα (p=0.040) stimulation in hyperglycemic condition. Conclusion: Baicalin attenuated fibrosis process by hyperglycemia associated factors in HK-2 cell. Disclosure J. Nam: None. J. Kim: None. K. Park: None. S. Lee: None. J. Nam: None. J. Park: None. S. Park: None. Y. Kim: None. C. Ahn: None.