title: Polysaccharides from Liriopes Radix ameliorate streptozotocin-induced type I diabetic nephropathy via regulating NF-κB and p38 MAPK signaling pathways.
abstract: BACKGROUND
  The polysaccharides from Liriopes Radix (PSLR) has been indicated to ameliorate insulin signaling transduction and glucose metabolism. We aimed to investigate whether PSLR exerts an ameliorative effect on renal damage in diabetes induced by streptozotocin.
  
  
  METHODS
  Diabetes was induced with STZ (60 mg/kg) by intraperitoneal injection in rats. Two weeks after STZ injection, rats in the treatment group were orally dosed with PSLR (200 and 300 mg/kg/day for 8 weeks. The normal rats were chosen as nondiabetic control group. Changes in renal function-related parameters in plasma and urine were analyzed at the end of the study. Kidneys were isolated for pathology histology, immunohistochemistry, and Western blot analyses.
  
  
  RESULTS
  Diabetic rats exhibited renal dysfunction, as evidenced by reduced creatinine clearance, blood urea nitrogen and proteinuria, along with marked elevation in the ratio of kidney weight to body weight. All of these abnormalities were significantly reversed by PSLR. The histological examinations revealed amelioration of diabetes-induced glomerular pathological changes following treatment with PSLR. The less protein expressions of renal nephrin and podocin in diabetic rats were increased following treatment with PSLR. PSLR reduced the accumulation of ED-1-expressing macrophages in renal tissue of diabetic rats. PSLR almost completely abolished T cells infiltration and attenuated the expression of proinflammatory cytokines. PSLR treatments not only reduced the degradation of inhibitory kappa B kinase, but also downregulated the protein expression of nuclear factor kappa B (NF-κB) and p38 mitogen-activated protein kinase (MAPK) in diabetic kidney.
  
  
  CONCLUSIONS
  The results suggest that the renal protective effects of PSLR occur through improved glycemic control and renal structural changes, which are involved in the inhibition of NF-κB and p-38 MAPK mediated inflammation.
authors.forename: Hung-Jen
authors.initials: HJ
authors.lastname: Lu
authors.forename: Thing-Fong
authors.initials: TF
authors.lastname: Tzeng
authors.forename: Shorong-Shii
authors.initials: SS
authors.lastname: Liou
authors.forename: Sheng
authors.initials: S
authors.lastname: Da Lin
authors.affiliation: Department of Food Science, College of Agriculture, National Pingtung University of Science and Technology, Neipu Township, Pingtung County, Taiwan. mcwu@mail.npust.edu.tw.
authors.forename: Ming-Chang
authors.initials: MC
authors.lastname: Wu
authors.forename: I-Min
authors.initials: IM
authors.lastname: Liu
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy / Q000378:metabolism; D003928:Diabetic Nephropathies / Q000378:metabolism / Q000517:prevention & control*; D007249:Inflammation / Q000378:metabolism; D007328:Insulin / Q000378:metabolism; D007668:Kidney / Q000187:drug effects; D019668:Liliaceae / Q000737:chemistry*; D020935:MAP Kinase Signaling System / Q000187:drug effects*; D008297:Male; D016328:NF-kappa B / Q000378:metabolism*; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use; D018517:Plant Roots / Q000737:chemistry; D011134:Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology* / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction; D013311:Streptozocin; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*
chemical_list: D001786:Blood Glucose; D007328:Insulin; D016328:NF-kappa B; D010936:Plant Extracts; D011134:Polysaccharides; D013311:Streptozocin; D048051:p38 Mitogen-Activated Protein Kinases