Qiling Tongluo Prescription Improves Renal Injury in Rats with Idiopathic Membranous Nephropathy by Inhibiting TLR4/MyD88/NF-κB Signaling Pathway / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo explore the therapeutic effect and mechanism of Qiling Tongluo prescription against idiopathic membranous nephropathy （IMN） in rats based on Toll-like receptor 4/myeloid differentiation factor 88/nuclear transcription factor-κB （TLR4/MyD88/NF-κB） signaling pathway. MethodSixty male SD rats were randomly divided into the normal group， model group， benazepril hydrochloride （10 mg·kg-1） group， and low-，medium-， and high-dose （6.48， 12.95， and 25.9 g·kg-1） Qiling Tongluo prescription groups. The IMN rat model was established by injection of cationized bovine serum albumin （C-BSA） into the tail vein. After the model was successfully prepared， the rats were gavaged with the corresponding drugs， once a day， for four consecutive weeks. After the treatment， the pathological changes in rat kidneys were observed by hematoxylin-eosin （HE） staining， Masson staining， and periodic acid-silver metheramine （PASM） staining， followed by the detection of 24 h urinary total protein （24 h UTP）， plasma albumin （ALB）， total serum protein （TP）， serum creatinine （SCr）， urea nitrogen （BUN）， and uric acid （UA） levels. The levels of interleukin-1β （IL-1β） and interleukin-6 （IL-6） were determined by enzyme-linked immunosorbent assay （ELISA）， and the mRNA and protein expression levels of TLR4， MyD88， and NF-κB in the kidney tissue were assayed by real-time fluorescent quantitative polymerase chain reaction （Real-time PCR）， immunohistochemistry （IHC）， and Western blot. ResultCompared with the normal group， the model group exhibited elevated 24 h UTP and serum SCr， BUN， UA， IL-1β， and IL-6 （P<0.05， P<0.01）， decreased ALB and TP （P<0.01）， up-regulated TLR4， MyD88， and NF-κB p65 mRNA and protein expression in kidney tissue （P<0.05， P<0.01）， obvious inflammation， disordered glomerular structure with enlarged volume， irregularly thickened basement membrane， inflammatory cell infiltration in the renal interstitium， reduced renal tubular epithelial cells due to shedding and apoptosis， and some vacuolar degeneration. Compared with the model group， benazepril hydrochloride and Qiling Tongluo prescription at the high dose remarkably lowered the serum SCr and UA （P<0.05） and increased ALB and TP （P<0.05）. Benazepril hydrochloride and Qiling Tongluo prescription at the low， medium， and high doses down-regulated the 24 h UTP， serum IL-1β and IL-6 levels， and renal TLR4， MyD88， and NF-κB p65 mRNA and protein expression to varying degrees （P<0.05， P<0.01）， alleviated IMN inflammatory reaction， glomerular swelling， and volume increase， slightly dilated glomerular capillaries， proliferated mesangial matrix， and relieved pathological and morphological damages in rat kidney， with inflammatory cell infiltration occasionally observed. ConclusionQiling Tongluo prescription may reduce the release and expression of inflammatory factors by regulating the TLR4/MyD88/NF-κB signaling pathway to inhibit the inflammatory response in IMN rats， ameliorate proteinuria and kidney damage， and protect kidney function.