Chinese Herbs Nephropathy Research Articles

Valvular heart disease and Chinese-herb nephropathy

Valvular heart disease and Chinese-herb nephropathy

Changing the Name of Chinese Herbs Nephropathy to Aristolochia Nephropathy or Aristolochic-Acid Nephropathy

In this article, the proposal to rename “Chinese herbs nephropathy” was reviewed. Prolonged use of Chinese herbs that contain aristolochic acid may induce tubulo-interstitial disorders. In our opinion, the “Chinese herbs nephropathy” nomenclature is equivocal, and should be changed to “aristolochic-acid nephropathy”. Professor Vanherweghem, who is the first author to write about this disease, also used the name “Aristolochia nephropathy.”

32P-post-labelling analysis of DNA adducts formed by aristolochic acid in tissues from patients with Chinese herbs nephropathy.

Recently, we reported that aristolochic acid (AA) a naturally occurring nephrotoxin and carcinogen is implicated in a unique type of renal fibrosis, designated Chinese herbs nephropathy (CHN). Indeed, we identified the principal aristolochic acid-DNA adduct in the kidney of five such patients. We now extend these observations and demonstrate the presence of additional AA-DNA adducts by the 32P-post-labelling method not only in the kidneys, but also in a ureter obtained after renal transplantation. Using the nuclease P1 version of the assay not only the major DNA adduct of aristolochic acid, 7-(deoxyadenosin-N6-yl)-aristolactam I (dA-AAI), but also the minor adducts, 7-(deoxyguanosin-N2-yl)-aristolactam I (dG-AAI) and 7-(deoxyadenosin-N6-yl)-aristolactam II (dA-AAII) were detected, and identified by cochromatographic analyses with TLC and HPLC. Quantitative analyses of six kidneys revealed relative adduct levels from 0.7 to 5.3/10(7) for dA-AAI, from 0.02 to 0.12/10(7) for dG-AAI and 0.06 to 0.24/ 10(7) nucleotides for dA-AAII. The detection of the dA-AAII adduct is consistent with the occurrence of aristolochic acid II (AAII) in the herb powder imported under the name of Stephania tetrandra and confirms that the patients had indeed ingested the natural mixture of AAI and AAII. 32P-post-labelling analyses of further biopsy samples of one patient showed the known adduct pattern of AA exposure not only in the kidney, but also in the ureter, whereas in skin and muscle tissue no adduct spots were detectable. In an attempt to explain the higher level of the dA-AAI adduct compared to the dG-AAI adduct level in renal tissue even 44 months after the end of regimen, the persistence of these two purine adducts was investigated in the kidney of rats given a single oral dose of pure AAI. In contrast to the dG-AAI adduct, the dA-AAI adduct exhibited a lifelong persistence in the kidney of rats. Our data demonstrate that AA forms DNA adducts in human tissue by the same activation mechanism(s) reported from animal studies. Thus, the carcinogenic/mutagenic activity of AA observed in animals could also be responsible for the urothelial cancers observed in two of the CHN patients.

Chinese herbs nephropathy presentation, natural history and fate after transplantation.

Chinese herbs nephropathy is a new type of subacute interstitial nephropathy reported in women who had followed a slimming regimen including Chinese herbs. We report the clinical presentation and follow-up of 15 cases and compare them with a control group of 15 women with interstitial nephropathies of other origins, matched for age, sex, and initial serum creatinine (mean 3 mg/dl). At presentation the Chinese herbs nephropathy group differed from the control group by a lower proteinuria (P = 0.009), a more severe anaemia (P = 0.002), and a higher prevalence of aortic insufficiency (42% vs 0%, P < 0.05). It was further characterized by mild hypertension in 80%, glycosuria and leukocyturia in 40% and asymmetric kidneys in 54% of the cases. During follow-up, deterioration of renal function was faster in the Chinese herbs nephropathy than in the control group (P < 0.05). It was influenced by the duration of Chinese herbs treatment (P = 0.037) and the delay between the end of Chinese herbs ingestion and diagnosis of the disease (P = 0.013). In three cases, renal failure developed 3 years after Chinese herbs ingestion. Complications included severe aortic regurgitation requiring surgery (n = 1), urothelial carcinoma (n = 2), bilateral ureterohydronephrosis due to periureteral fibrosis (n = 1). Five patients with Chinese herbs nephropathy were successfully transplanted, without evidence of recurrence of the disease. Chinese herbs nephropathy is characterized by a lower proteinuria, more severe anaemia, and a faster progression to renal failure than other interstitial nephropathies. The duration of Chinese herbs treatment and interval between withdrawal of Chinese herbs and diagnosis are correlated with the rate of progression. Severe, unusual extrarenal complications may affect Chinese herbs nephropathy patients.

Proximal tubular injury in Chinese herbs nephropathy: Monitoring by neutral endopeptidase enzymuria

Neutral endopeptidase (NEP) is a 94 kDa ectoenzyme of the proximal tubule brush border, physiologically released into the urine with apical membrane fragments. As proximal tubular atrophy was a histological hallmark of Chinese herbs nephropathy (CHN), this study firstly determined renal excretion of NEP in healthy control subjects (N = 31), in patients with CHN (N = 26) and in women having consumed Chinese herbs and whose renal function was normal but running the risk of developing CHN (N = 27). Another patient group consisted of female patients with glomerular diseases (N = 12). At the same time, measurements of urinary microproteins (Clara cell protein, retinol binding protein, beta 2-microglobulin and alpha 1-microglobulin) were performed, as indicators of tubular dysfunction. Cell damage was estimated by the excretion of N-acetyl-beta-D-glucosaminidase (NAG). In the control group, the physiological NEP enzymuria was 43.1 micrograms/24 hr (geometric mean). In CHN patients, levels of urinary NEP were significantly decreased in those with moderate renal failure (26.7 micrograms/24 hr; N = 21; P < 0.05) and almost abolished in end-stage renal failure patients (4.35 micrograms/24 hr; N = 5; P < 0.05). In patients at risk as well as in patients with glomerular diseases, urinary NEP levels were not statistically different from those observed in control subjects (40.68 micrograms/24 hr and 48.5 micrograms/24 hr, respectively). Several degrees of tubular dysfunction and injury were noted in patients groups, as attested by increased urinary microproteins and NAG excretions. Considering the data from control and CHN patients, NEP enzymuria positively correlated with individual creatinine clearance values (r = 0.76; P = 0.0001) and negatively correlated with urinary microproteins levels (r = -0.55; P = 0.00001). Finally, NEP was regularly quantitated in the urine of 6 CHN patients for a period ranging from six months to two years and in 19 patients at risk during two years, respectively. In the first group, renal function progressively deteriorated in 3 patients, leading them to renal replacement therapy after 38 to 115 weeks. Stable parameters were observed in the remaining 3 patients. A direct correlation between creatinine clearance and NEP excretion was found longitudinally in each case. In the second group, no significant change of urinary NEP levels was observed (45.9 micrograms/24 hr), in parallel with stable renal function. Taken together, these results indicate that, in CHN patients, NEP enzymuria provides a rapid and noninvasive determination of the degree of structural impairment affecting the proximal tubular population and further reflecting the severity of the renal disease. The interest of this urinary marker in monitoring the progression of other tubulointerstitial diseases remains to be assessed.

関西地方におけるChinese herbs nephropathyの多発状況について

In 1993, Vanherweghem and his associates reported cases of rapidly progressive renal interstitial fibrosis in young women who were administered a slimming regimen including Chinese herbs. Subsequently, similar cases have been reported. In Japan, especially in the Kansai area, several cases of Chinese herbs nephropathy have already been reported. We experienced a patient suffering from Chinese herbs nephropathy (CHN), and further detected aristolochic acids from the Chinese herbs taken by the patient. Aristolochic acids are known to be causative agents of CHN. The danger of CHN should be noted as soon as possible and drugs containing aristolochic acids should be prohibited.

Effects of steroids on the progression of renal failure in chronic interstitial renal fibrosis: A pilot study in Chinese herbs nephropathy

Chinese herbs nephropathy is characterized by an extensive interstitial fibrosis and by a rapid evolution to end-stage renal failure. We thus decided to try steroid therapy (prednisolone 1 mg/kg for 1 month, tapered off 0.1 mg/kg every 2 weeks) in cases with moderate renal failure and evidence of deterioration in renal function. Our steroid group (SG) consisted of 12 female patients with biopsy-proven renal fibrosis who were followed for at least 12 months after the initiation of steroids. Plasma creatinine level (P creat) ranged from 1.8 to 3.9 mg/dL (mean ± SEM, 2.8 ± 0.2 mg/dL) when steroids were initiated at t = 0. Renal failure was in progression since P creat was 2.1 ± 0.1 mg/dL ( P = 0.022) 3 months before t = 0. Our control group (CG; N = 23) was selected retrospectively from among the 81 patients in the Belgian Register of Chinese Herbs Nephropathy. Compared with the CG, renal function was better preserved in the SG (P creat; mean ± SEM): SG v CG, 2.9 ± 0.3 mg/dL v 5.3 ± 0.5 mg/dL at 6 months ( P = 0.0024) and 4.0 ± 0.7 mg/dL v 7.1 ± 0.5 mg/dL at 1 year ( P = 0.001). The slope of the reciprocal serum creatinine concentration was similar in both groups before t = 0 (−0.0463 mg/dL/mo in the SG v −0.0438 mg/dL/mo in the CG; P = 0.83), but it became less steep after initiation of steroid therapy (between 0 and 6 months, −0.000742 mg/dL/mo in the SG v −0.0284 mg/dL/mo in the CG; P < 0.001). Finally, only two of the 12 patients in the SG required dialysis at 1 year compared with 16 of the 23 patients in the CG ( P = 0.0045). We conclude that steroid therapy slows the progression of renal failure in a disease characterized by an interstitial fibrosis that progresses quickly despite the fact that the insulting agent has been withdrawn. This supports the hypothesis that renal interstitial fibrosis may be an immune-mediated process.

Low molecular weight proteinuria in Chinese herbs nephropathy

Urinary excretion of five low molecular weight proteins (LMWP) [beta 2-microglobulin (beta 2m), cystatin C (cyst C), Clara cell protein (CC16), retinol-binding protein (RBP) and alpha 1-microglobulin (alpha 1m)], albumin and N-acetyl-beta-D-glucosaminidase (NAG) were quantified in 16 patients who followed a weight reduction program which included Chinese herbs, which have been incriminated in the genesis of Chinese herbs nephropathy (CHN). An additional group of four patients transplanted for CHN were investigated. Urinary data were obtained for comparison purpose in five groups of proteinuric patients: two groups with normal serum creatinine (SCr) and glomerular albuminura [12 patients with diabetes mellitus and microalbuminuria (DN), 10 patients with primary nephrotic syndrome (NS)]; two groups with normal SCr and toxic nephropathy [6 patients with analgesic (AN), 9 patients with cadmium nephropathy (CdN)]; and one group of seven patients with glomerular diseases and increased SCr (GN). Patients were classified according to serum level S beta 2m to take into account the possibility of overflow proteinuria at S beta 2m > or = 5 mg/liter. Three patients (CHN0) with a S beta 2m < 5 mg/liter, had a normal urinary protein pattern including NAG and a normal S beta 2m. Eight patients (CHN1) with a S beta 2m < 5 mg/liter had various abnormalities of their urinary protein pattern. In four of them (CHN1a) only beta 2m, RBP and CC16 were increased while total proteinuria and SCr were normal. In the other four (CHN1b and c) albumin, cyst C, alpha 1m and NAG were also elevated, while total proteinuria and SCr were moderately raised. Five patients (CHN2) with a S beta 2m > or = 5 mg/liter had a markedly increased excretion of all LMWP, albumin and NAG (CHN1 vs. CHN2, P < 0.05) as well as a further increase in total proteinuria and SCr. The urinary LMWP/albumin concentration ratio was strikingly higher in CHN patients than in patients with glomerular albuminuria (CHN1 vs. DN and NS, P < 0.01) or moderate renal failure with elevated S beta 2m level (CHN2 vs. GN, P < 0.01), confirming the existence of a tubular proteinuria independent of glomerular albuminuria or overflow proteinuria. A similar proteinuria pattern was present in the two toxic nephropathies (CdN and AN). This pattern was no longer recognizable after transplantation. In conclusion, CHN exhibits various profiles of tubular proteinuria which are the hallmarks of the disease. This pattern is still detectable in patients with renal failure and/or glomerular albuminuria. It is identical to that observed in cadmium and analgesic nephropathies. It does not recur after transplantation. Its most sensitive and reliable marker is a raised urinary level of CC16 or RBP.

Chinese herbs nephropathy and renal pelvic carcinoma

Chinese herbs nephropathy and renal pelvic carcinoma

The tragic paradigm of Chinese herbs nephropathy

The tragic paradigm of Chinese herbs nephropathy

Purification and characterisation of immunoglobulins bound to the placenta of sheep

Aristolochic acid impedes endocytosis and induces DNA adducts in proximal tubule cells.Aristolochic acid (AA), present in Aristolochia plants, appears to be the toxin responsible for Chinese herbs nephropathy (CHN), a rapidly progressive tubulointerstitial nephritis. One of the earliest sign of CHN is the urinary excretion of low-molecular-weight proteins (LMWP), suggesting that AA is toxic to proximal tubules (PT).The effects of AA on PT functions including reabsorption of LMWP were investigated on the well-established opossum kidney (OK) cell line, a model for PT, and compared with those of the classical PT toxin cadmium chloride (CdCl2).OK cell monolayers internalized albumin and β2-microglobulin by receptor-mediated endocytosis, both proteins apparently competing for the same receptor, a complex of megalin and cubulin. The process was significantly impaired by 24-hour preincubation with AA (10 or 20 μmol/L) or CdCl2 (15 μmol/L). Furthermore, 24-hour exposure to AA followed by its removal during one to six days led to a persistent inhibition of the uptake of albumin, in contrast to the substantial recovery observed after CdCl2 removal. Neither AA nor CdCl2 affected cell viability, Na+-glucose cotransport or total rate of protein synthesis. AA significantly decreased megalin expression and formed specific DNA adducts in OK cells, similar to those found in kidneys from CHN patients.The present data support the involvement of AA in the early PT dysfunction found in CHN; furthermore, they suggest a causal relationship between DNA adduct formation, decreased megalin expression, and inhibition of receptor-mediated endocytosis of LMWP.

Fetal IGF-1 and IGFBP-2 response to betamethasone and thyroxine

Aristolochic acid impedes endocytosis and induces DNA adducts in proximal tubule cells.Aristolochic acid (AA), present in Aristolochia plants, appears to be the toxin responsible for Chinese herbs nephropathy (CHN), a rapidly progressive tubulointerstitial nephritis. One of the earliest sign of CHN is the urinary excretion of low-molecular-weight proteins (LMWP), suggesting that AA is toxic to proximal tubules (PT).The effects of AA on PT functions including reabsorption of LMWP were investigated on the well-established opossum kidney (OK) cell line, a model for PT, and compared with those of the classical PT toxin cadmium chloride (CdCl2).OK cell monolayers internalized albumin and β2-microglobulin by receptor-mediated endocytosis, both proteins apparently competing for the same receptor, a complex of megalin and cubulin. The process was significantly impaired by 24-hour preincubation with AA (10 or 20 μmol/L) or CdCl2 (15 μmol/L). Furthermore, 24-hour exposure to AA followed by its removal during one to six days led to a persistent inhibition of the uptake of albumin, in contrast to the substantial recovery observed after CdCl2 removal. Neither AA nor CdCl2 affected cell viability, Na+-glucose cotransport or total rate of protein synthesis. AA significantly decreased megalin expression and formed specific DNA adducts in OK cells, similar to those found in kidneys from CHN patients.The present data support the involvement of AA in the early PT dysfunction found in CHN; furthermore, they suggest a causal relationship between DNA adduct formation, decreased megalin expression, and inhibition of receptor-mediated endocytosis of LMWP.

Chinese herb nephropathy - follow-up recommended

Chinese herb nephropathy - follow-up recommended

Chinese herb nephropathy ??? follow-up recommended

Chinese herb nephropathy ??? follow-up recommended

Chinese herbs nephropathy: A clue to Balkan endemic nephropathy?

Rapidly progressive interstitial renal fibrosis has recently been reported in young women who have been on a slimming regimen including Chinese herbs. We examined four nephroureterectomies performed in three patients prior to or at the time of transplantation to determine the nature and topography of the kidney and urinary tract lesions in Chinese herbs nephropathy (CHN). Extensive, hypocellular, interstitial sclerosis, tubular atrophy and global sclerosis of glomeruli decreasing from the outer to the inner cortex, including the columns of Bertin, were observed in the four kidney specimens, together with severe fibromucoid to fibrous intimal thickening, mainly of interlobular arteries, normal or collapsed residual glomeruli, and mild to moderate atypia and atypical hyperplasia of the urothelium. In addition, bilateral pelvi-ureteric sclerosis was observed in one case. With the exception of the latter, these lesions are very similar to those described in Balkan endemic nephropathy (BEN). The clinical presentation of the patients was also similar to that observed in BEN: normal blood pressure, aseptic leukocyturia, low grade low molecular weight proteinuria, early and severe anemia. In conclusion, on morphological and clinical grounds, CHN appears similar to BEN. A common etiologic agent, aristolochic acid, is suspected. The known carcinogenic potential of this compound, taken together with our finding of multiple foci of cellular atypia of the urothelium suggest that CHN patients should undergo a regular follow-up for urothelial malignancy.