[Regulatory effect of Astragalus membranaceus on the immune disorder in rats with IgA nephropathy].
OBJECTIVE
To study the regulattory effect of Astragalus membranaceus on immune disturbance of the rats with IgA nephropathy.


METHODS
Rats IgA nephropathy (IgAN) model was duplicated by oral feeding of bovine serum albumin (BSA), subcutaneous injection of carbon tetrachloride (CCl4) and injection of lipopolysaccharide (LSP) into vena caudalis. The rats were divided into three groups randomly for the normal, IgAN model group and the group treated with Astragalus membranaceus (treatment group). The treatment group was given the Astragalus membranaceus granules via intragastric administratsion, the normal group and the IgAN model group were given the equal amount of aqua destillata by gastric perfusion. The rats were examined for albuminuria, hematuria and pathological changes of renal tissue and the distribution of TGF-beta and interleukin-5 in renal tissue was determined by immunohistochemistry and the IFN-gamma and IL-4 of cytokine of Th1 and Th2 types were detected in rats IgA nephropathy model by sandwich enzyme linked immunosorbent assay (ELISA).


RESULTS
(1) The hematuria in rats with IgA nephropathy significantly increased compared with normal control group and Astragalus treatment group (P < 0.05). There was significant increase in albuminuria in rats with IgA nephropathy, compared with normal control group and astragalus treatment group (P < 0.01). (2) The pathological change of glomerular mesangium, renal tubules and renal interstitia became serious in rats IgA nephropathy model when compared with normal control group and astragalus treatment group. Immumofluorescence showed renal IgA density in rats IgA nephropathy model was significantly higher than that in the normal control group (P < 0.001) and astragalus treatment group (P < 0.001). (3) The result of immuno histochemistry showed that there was only weak expression of TGF-beta and interleukin 5 in normal renal tissue. The expression of TGF-beta and interleukin 5 in IgA nephropathy model was significantly stronger than those in normal control group (P < 0.05) and astragalus treatment group (P < 0.05). (4) The serum IL-4 levels were (33.74 +/- 7.52) pg/ml in rats IgA nephropathy model, significantly higher than that in normal control group (2.36 +/- 0.85) pg/ml and astragalus treatment group (3.24 +/- 1.13) pg/ml. The IFN-gamma level in serum of rats IgA nephropathy model was (18.79 +/- 3.80) pg/ml, which was significantly higher than that in normal control group (46.53 +/- 5.56) pg/ml and astragalus treatment group (41.28 +/- 2.95) pg/ml.


CONCLUSIONS
The astragalus could lower the level of hematuria and 24 hours-albuminuria of the IgAN model, and amelioratse the change of the renal pathology and reduce the deposit of IgA in glomerular mesangium. The possible mechanism of the effect is that astragalus could regulate the derangement of Th1, Th2, accordingly could improve the level of IL-4 and IFN-gamma in the serum and diminish the expression of cytokine Th2 TGF-beta1 and IL-5 of the renal tissue, and thereby could postpone the development of IgAN.
Peng
Xiao-jie
XJ
Pediatric Nephrology Unit and Laboratory, the Second Xiangya Hospital of Central South University, Changsha 410011, China.
Wu
Xiao-chuan
XC
Zhang
Guo-zhen
GZ
Yi
Zhu-wen
ZW
Zheng
Wei-min
WM
He
Xiao-jie
XJ
Mo
Shuang-hong
SH
Tan
Hong
H
D000818:Animals; D027885:Astragalus propinquus / Q000737:chemistry* / Q000276:immunology*; D002417:Cattle; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D005922:Glomerulonephritis, IGA / Q000276:immunology*; D015847:Interleukin-4 / Q000494:pharmacology; D015848:Interleukin-5 / Q000494:pharmacology; D007684:Kidney Tubules / Q000187:drug effects; D051381:Rats; D016212:Transforming Growth Factor beta / Q000276:immunology; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology*
D004365:Drugs, Chinese Herbal; D015848:Interleukin-5; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D015847:Interleukin-4