Expression and cellular distribution of TLR4, MyD88, and NF-κB in diabetic renal tubulointerstitial fibrosis, in vitro and in vivo

Autor: Ming-cai Qiu, Lanjie He, Fengao Li, Ping Liu
Rok vydání: 2014
Předmět:
Male
medicine.medical_specialty
Epithelial-Mesenchymal Transition
Endocrinology
Diabetes and Metabolism
Blotting
Western
Fluorescent Antibody Technique
Inflammation
Real-Time Polymerase Chain Reaction
Diabetes Mellitus
Experimental
Immunoenzyme Techniques
Rats
Sprague-Dawley
Diabetic nephropathy
Pathogenesis
chemistry.chemical_compound
Endocrinology
Western blot
In vivo
Internal medicine
Internal Medicine
medicine
Animals
Diabetic Nephropathies
RNA
Messenger
Cells
Cultured
medicine.diagnostic_test
Reverse Transcriptase Polymerase Chain Reaction
business.industry
Macrophages
NF-kappa B
NF-κB
General Medicine
medicine.disease
Fibrosis
Extracellular Matrix
Rats
Up-Regulation
Toll-Like Receptor 4
Glucose
Kidney Tubules
chemistry
Sweetening Agents
Myeloid Differentiation Factor 88
Tubulointerstitial fibrosis
TLR4
Nephritis
Interstitial
medicine.symptom
business
Zdroj: Diabetes Research and Clinical Practice. 105:206-216
ISSN: 0168-8227
Popis: Inflammation and extracellular matrix hyperplasia are crucial in the pathogenesis of tubulointerstitial fibrosis (TIF) involved in diabetic nephropathy (DN). Macrophage accumulation plays a major role, but whether immune factors contribute to DN pathogenesis is not well understood. This study aimed to investigate TLR4-MyD88-NF-κB-dependent pathway's involvement in TIF pathogenesis.STZ-induced diabetic rats and rat renal tubular epithelial NRK-52E cells cultured under high glucose conditions were used as in vivo and in vitro models, respectively. Real-time RT-PCR, western blot, immunohistochemistry and immunofluorescence were performed to examine the mRNA and protein levels of TLR4, MyD88, NF-κB, MCP-1, and α-SMA.Compared with 5.5 mmol/L glucose, treatment of NRK-52E cells with 25 and 50 mmol/L d-glucose resulted in significantly increased TLR4 and MyD88 mRNA and protein levels (P0.05). TLR4 and MyD88 were detected in the cytoplasm of most NRK-52E cells cultured under high glucose. Pronounced damage in the renal tubulointerstitium was observed in diabetic rats (scores: 3.82 ± 0.65 vs. 0.38 ± 0.08, P0.01). Compared with the normal controls, a sharp upregulation of TLR4, MyD88, NF-κB p65, MCP-1, and α-SMA mRNA and protein levels was observed in diabetic rat kidneys (P0.05). In diabetic animals, TLR4 and MyD88 were strongly expressed in the cytoplasm, while NF-κB p65 was widely expressed in cytoplasm and nuclei of renal tubular epithelial cells.The inflammatory reaction and epithelial-mesenchymal transformation observed in renal tubulointerstitium may be the result of overactivation of the TLR4-MyD88-NF-κB-dependent innate immunity under high glucose, and may be involved in DN occurrence and progression.
Databáze: OpenAIRE
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