- Email: [email protected]
Therapeutic Effect of Tripterygium wilfordii on Proteinuria Associated With Sirolimus in Renal Transplant Recipients
Therapeutic Effect of Tripterygium wilfordii on Proteinuria Associated With Sirolimus in Renal Transplant Recipients S.M. Ji, L.S. Li, J.Q. Wen, G.Z. Sha, Z. Cheng, D.R. Cheng, J.S. Chen, and Z.H. Liu ABSTRACT Sirolimus (SRL) is a potent immunosuppressive drug used to prevent acute allograft rejection after renal transplantation. Nevertheless, the occurrence of proteinuria has recently been recognized among patients on SRL-based therapy. The aim of this study was to investigate the therapeutic effects of Tripterygium wilfordii Hook F. (T II) on proteinuria associated with SRL in renal transplant recipients. According to accepting T II, 36 recipients were divided into 2 groups: T II group (n ⫽ 21) and valsartan group (n ⫽ 15). The T II group was administered 1 mg/kg/d, and the valsartan group, 80 mg twice per day for 12 months. Efficiency was then evaluated. Complete remission: proteinuria decreased by ⬎50%; partial remission: proteinuria decreased by 20% to 50%; ineffective: proteinuria decreased by ⬍20%. Upon 12-month follow-up, the total effective rates in the T II group and the valsartan group were 95.2% and 86.7% (P ⬍ .05), respectively. Twenty of 21 patients with proteinuria in the T II group were negative at 3-month follow-up with disappearance of edema. There were some adverse events that had greater incidence rates in the valsartan group compared with the T II group, such as hyperkalemia (26.7% vs 4.8%). We concluded that the application of T II markedly reduced proteinuria associated with SRL in renal transplant patients.
S
IROLIMUS (SRL) is a potent immunosuppressive drug used for the prevention of acute allograft rejection after renal transplantation.1 SRL regimens have been either as a de novo immunosuppressive protocol or in a conversion protocol from calcineurin inhibitors (CNI) to SRL.2– 4 Nevertheless, the occurrence of proteinuria has recently been recognized among patients on SRL-based therapy,5,6 an adverse event that affects deterioration of long-term renal function. Tripterygium wilfordii Hook F., called T II, has been used as an insecticide for many centuries in traditional Chinese medicine. Only in the past 20 years has it been used to treat a variety of autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus, with promising results.7,8 It was first used in the treatment of glomerular disease by a group of workers from Jinling Hospital in 1997.9 The chemistry of the plant has been studied: 15 alkaloids, 15 triterpenoids, and 12 diterpenoids have been isolated from the plant, among which diterpenoids are believed to be the most important useful compounds for nephrological practice.10 We pioneered a therapeutic trial of T II in glomerular disease. Triptolide, an active fraction purified from an extract of T. wilfordii, increased the
remission rates of nephritic proteinuria, including IgA nephritis, IgM nephritis, and mesangial proliferative glomerulonephritis (MsPGN).9,11 The purpose of this study was to investigate the therapeutic effects of T. wilfordii Hook F. on proteinuria associated with SRL among renal transplant recipients. PATIENTS AND METHODS Patient Population Among 124 cadaveric renal allograft recipients transplanted between April 2001 and November 2006, we enrolled 36 patients (24 males and 12 females) of ages ranging from 22 to 48 years due to severe proteinuria caused by SRL prescribed either as a de novo immunosuppressant or in a conversion protocol. Proteinuria was diagnosed by 24-hour urine collections performed routinely or when patients showed edema or when detected on urinalysis. From the Research Institute of Nephrology (S.M.J., J.Q.W., G.Z.S., Z.C., D.R.C., J.S.C.), Department of Nephropathy, Jinling Hospital, Nanjing, China, and Nanjing University School of Medicine (L.S.L., Z.H.L.), Nanjing, China. Address reprint requests to Dr Lei-shi Li, Research Institute of Nephrology, Jinling Hospital, 305 East Zhong Shan Road, Nanjing 210002, China. E-mail: [email protected]
0041-1345/08/$–see front matter doi:10.1016/j.transproceed.2008.07.140
© 2008 by Elsevier Inc. All rights reserved. 360 Park Avenue South, New York, NY 10010-1710
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EFFECT OF TRIPTERYGIUM ON PROTEINURIA
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Thirty-six patients developed proteinuria (⬎1.5 g/24 h) on SRL for 1 to 6 months. Only 6/31 patients (19.4%) receiving SRL de novo developed proteinuria, and 30 patients (30/93; 32.3%) displayed proteinuria after abrupt cessation of a CNI. The mean value of proteinuria was 4.4 ⫾ 2.9 g/24 h (range, 1.5–7.3 g/24 h). Patients presenting any degree of proteinuria before conversion to SRL were not enrolled in the study. Only patients who developed de novo proteinuria after SRL were included in this analysis. Primary diseases included chronic glomerulonephritis (n ⫽ 26; 72.2%), hypertensive nephropathy (n ⫽ 2; 5.6%), polycystic kidney disease (n ⫽ 2; 5.6%), purpuric nephritis (n ⫽ 2; 5.6%), lupus nephritis (n ⫽ 2; 5.6%), and gouty nephropathy (n ⫽ 2; 5.6%).
Study Design Patients were randomly assigned to treatment with T II (T II group; n ⫽ 21) or without T II (valsartan group; n ⫽ 15) for 12 months. There was no significant difference between the 2 groups in sex, age, mean blood pressure serum albumin level, hemoglobin, fasting blood glucose, proteinuria, levels of serum creatinine (SCr) and serum total cholesterol (TC), and triglycerides (TG). There also was no significant difference between the 2 groups in mean daily dosage of mycophenolate mofetil (MMF), MMF AUC 0 –12, cyclosporine, or tacrolimus before enrollment. Hypertension was defined as a diastolic blood pressure (DBP) ⬎90 mm Hg and/or a systolic blood pressure (SBP) ⬎140 mm Hg at 2 or more visits. The study was approved by our ethics committee; all patients gave written informed consent.
Dosage of T II T II (1 mg/kg/d) was continued over 1 year. Tripterygium wilfordii Hook F. was provided by Mei-Tong Pharmaceutical Ltd (TaiZhou, China) as a 10 mg triptolide. During the overall clinical follow-up, all patients did not use angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB). Patients with hypertension were given calcium channel antagonists, -receptor blockers, ␣-receptor blockers, and/or loop diuretics to control blood pressure at 120/80 mm Hg.
Dosage of Valsartan Patients who continued to meet the eligibility criteria were administered open-label valsartan (Beijing Novartis Pharma Ltd) in an
initial dosage of 80 mg/d, force titrated to 80 mg twice per day after 1 week. Treatment with valsartan was continued for 12 months. When necessary, the doses of other antihypertensive medications were altered to maintain the goal blood pressure of 120/80 mm Hg.
Immunosuppressive Protocol These patients underwent abrupt cessation of cyclosporine or tacrolimus the evening before and SRL (Rapamune, Wyeth) addition the following morning as a first dose of 6 mg orally, thereafter, a maintenance dosage of 2 mg/d. The SRL doses were adjusted to obtain trough blood levels in the range of 6 to 10 ng/mL (ELISA method). SRL trough blood levels were monitored 7 days after conversion, every week for the first month, every 2 weeks for the second and third months, then monthly thereafter. After conversion, MMF (Cell Cept, Roche Pharmaceutical Co, Ltd), 750 mg twice per day, was adjusted by AUC 0 –12 to be maintained at 35 to 45 mg/h/L. In both groups, steroid therapy was unchanged.
Evaluation of Efficiency Complete remission: proteinuria decreased by ⬎50%; partial remission: proteinuria decreased by 20% to 50%; ineffective: proteinuria decreased by ⬍20%.
Statistical Analysis We used JMP software version 6.0 (SAS Institute Inc, Cary, NC, United States) for statistical analysis. For categorical data, the Fisher exact test or Pearson chi-square test was used. Parametric continuous data were analyzed by Student t tests. For nonparametric continuous data, we employed Wilcoxon rank-sum tests. P ⬍ .05 (2-sided) was considered significant.
RESULTS Baseline Characteristics
The patients’ clinical and laboratory data during the 12month follow-up are summarized in Table 1. SBP and DBP remained stable for the T II treatment study period: SBP 137.1 ⫾ 26.4 vs 127.8 ⫾ 24.3 mm Hg and DBP 89.2 ⫾ 4.3 vs 83.4 ⫾ 4.9 mm Hg (P ⫽ .87). SBP fell from 139.8 ⫾ 6.2 to 128.2 ⫾ 6.0 mm Hg and DBP 84.2 ⫾ 4.3 to 82.4 ⫾ 4.9 mm Hg (P ⫽ .84) by the end of the 12 months of valsartan
Table 1. Clinical and Laboratory Data T II Group (n ⫽ 21)
SBP (mm Hg) DBP (mm Hg) Mean proteinuria level (g/24 h) Serum albumin level (g/L) Hemoglobin level (g/L) Blood glucose (mmol/L) Total cholesterol (mmol/L) Serum triglyceride (mmol/L) Serum creatinine (mg/dL) Serum potassium (mmol/L) *P ⬍ .05, 12 months vs baseline. † P ⬍ .001, 12 months vs baseline.
Valsartan Group (n ⫽ 15)
Baseline
12 Months
Baseline
12 Months
137.1 ⫾ 26.4 89.2 ⫾ 4.3 4.4 ⫾ 2.9 36.4 ⫾ 2.9 13.1 ⫾ 2.2 5.5 ⫾ 1.0 6.6 ⫾ 1.2 3.1 ⫾ 1.0 1.6 ⫾ 0.5 4.3 ⫾ 0.1
127.8 ⫾ 24.3 83.4 ⫾ 4.9 0.9 ⫾ 0.2† 41.1 ⫾ 1.2* 12.1 ⫾ 2.2 5.4 ⫾ 1.1 5.5 ⫾ 2.1* 2.5 ⫾ 1.4* 1.2 ⫾ 0.4* 4.2 ⫾ 0.2
139.8 ⫾ 6.2 84.2 ⫾ 4.3 4.3 ⫾ 2.7 36.8 ⫾ 3.0 13.3 ⫾ 3.2 5.0 ⫾ 1.1 6.5 ⫾ 2.1 2.9 ⫾ 1.3 1.6 ⫾ 0.3 4.1 ⫾ 0.5
128.2 ⫾ 6.0 82.4 ⫾ 4.9 1.6 ⫾ 0.5† 37.9 ⫾ 4.2 11.3 ⫾ 3.2 4.4 ⫾ 1.9 6.9 ⫾ 1.1 2.0 ⫾ 1.3 2.1 ⫾ 0.5* 4.9 ⫾ 1.3
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JI, LI, WEN ET AL
therapy, but remained stable thereafter. However, the mean proteinuria level in the T II group was significantly lower than the valsartan group (P ⬍ .001). The serum albumin level in the T II group was significantly higher than the valsartan group (41.1 ⫾ 1.2 vs 37.9 ⫾ 4.2 g/L; P ⬍ .05). The serum hemoglobin level in the T II group was higher than the valsartan group (12.1 ⫾ 2.2 vs 11.3 ⫾ 3.2 g/L). There was no significant difference in fasting blood glucose: 5.4 ⫾ 1.1 vs 4.4 ⫾ 1.9 mmol/L (P ⫽ .81). TC and TG levels in the T II group were significantly lower than the valsartan group (P ⬍ .05). In the valsartan group, blood TC and TG levels did not clearly change and even showed an increasing tendency, namely, 6.5 ⫾ 2.1 vs 6.9 ⫾ 1.1 and 2.0 ⫾ 1.3 vs 2.9 ⫾ 1.3 mmol/L, respectively. As for the mean SCr at 3, 6, and 12 months follow-up, each value among the T II group was lower than that of the valsartan group (1.6 ⫾ 0.5 vs 1.6 ⫾ 0.3, 1.5 ⫾ 0.3 vs 1.8 ⫾ 0.5, and 1.2 ⫾ 0.4 vs 2.1 ⫾ 0.5 mg/dL; P ⬍ .05). Efficiency
At 12 months, the total effective rates in the T II group and the valsartan group were respectively 95.2% and 86.7% (P ⬍ .05; Table 2), and the ineffective rates 4.8% versus 13.3% (P ⬍ .001). However, 3 cases occurred in the ineffective group: 1 case in the T II group and 2 cases in the valsartan group. When the 3 patients (8.3%) had SRL withdrawn, we observed reversion of proteinuria and edema upon conversion to tacrolimus at 3, 3, or 6 months after conversion to SRL.
Time follow-up (months) (%)
W W TXW
X
Y
Z
[
\
]
}GGOGdGXZP {G p p G G G G GOGdGYWP
TYW TZW
P<0.001
T[W T\W T]W T^W
Fig 1.
Decreased extent of proteinuria in the 2 groups.
Dosage of SRL at Time of Proteinuria
There was no significant difference between the 2 groups in mean MMF AUC 0 –12 or SRL trough blood levels: 45 ⫾ 3.5 vs 46 ⫾ 3 mg/h/L and 5.8 ⫾ 0.4 vs 5.9 ⫾ 0.3 g/L, respectively. The dosage of SRL at the time of proteinuria ranged from 1.5 to 7.3 mg/24 h (mean, 4.4 ⫾ 2.9 g/24 h), with SRL trough blood levels ranging from 5.4 to 10.3 ng/mL (mean, 6.4 ⫾ 0.7 ng/mL). There was no correlation between proteinuria levels and SRL dosage (r ⫽ .44; P ⫽ NS), or SRL trough blood levels (r ⫽ .27; P ⫽ NS). All patients were followed for 12.2 (⫾3.7) months after treatment. There were no rejection episodes during the 12month follow-up. Adverse Events
Decreased Extent of Proteinuria
The 2 levels of proteinuria dropped in the 2 groups, but the decreased extent of proteinuria was more obvious in the T II group than the valsartan group (Fig 1). Mean proteinuria was 4.2 ⫾ 1.7 g/d at baseline in the T II group and fell to 0.9 ⫾ 0.2 g/d at the end of the study. Twenty of 21 patients with proteinuria in the T II group were negative at 3-month follow-up with disappearance edema. Patients in the valsartan group also showed decreased proteinuria, but none of them were negative, and the SCr level was constantly rising. Two patients developed kidney graft insufficiency with SCr levels of 4.0 mg/dL, and accompanying hyperkalemia, requiring patient to return to hemodialysis therapy after 9 months.
Table 2. Comparison of Efficiency Between the 2 Groups
Complete remission, n (%) Partial remission, n (%) Ineffective, n (%) Total effective rate (%)
T II Group (n ⫽ 21)
Valsartan Group (n ⫽ 15)
P
16 (76.2) 4 (19.0) 1 (4.8) 95.2
8 (53.3) 5 (33.3) 2 (13.3) 86.7
⬍.001 ⬍.05 ⬍.001 ⬍.001
All patients tolerated T II over the 12 months of this study. However, there were some adverse events that had greater incidence rates in the valsartan group compared with the T II group, namely, hyperkalemia (26.7% vs 4.8%). The mean serum potassium trended upward during valsartan treatment from 4.1 ⫾ 0.5 to 4.9 ⫾ 1.3 mmol/L. In 2 patients there was a need to reduce or discontinue valsartan therapy because of persistent hyperkalemia (serum potassium ⬎6.0 mmol/L). Other adverse events included cough (26.6% vs 0%), numbness (6.7% vs 0%), dry mouth (13.3% vs 0%), fatigue (26.6% vs 4.8%), headache (26.6% vs 0%), and sore throat (33.3% vs 4.8%). The incidences of herpes simplex (13.3% vs 0%), cutaneous herpes zoster infections (0% vs 0%), leukopenia (6.7% vs 0%), liver dysfunction (6.7% vs 0%), and gastrointestinal events (13.3% vs 4.8%) beween the 2 groups showed obvious differences. DISCUSSION
The present study suggested that heavy proteinuria was observed in 29.0% of patients receiving SRL-based immunosuppression at our center, developing prominently in the first 3 months after the initiation of SRL. Herein we have evaluated the safety and efficacy on proteinuria associated with SRL in renal transplant patients, comparing Triptery-
EFFECT OF TRIPTERYGIUM ON PROTEINURIA
gium with a valsartan-based immunosuppressive regimen in renal transplant recipients. Our results from this follow-up study demonstrated that the levels of proteinuria dropped in the 2 groups; the total effective rates in the T II and the valsartan groups were 95.2% and 86.7%, respectively. The side effects were minimal in the T II group. However, increased hyperkalemia occurred in 2/10 patients in the valsartan group, requiring interruption or cessation of valsartan therapy. This study suggested that the application of T II showed greater effects than valsartan to reduce proteinuria associated with SRL in renal transplant patients. Proteinuria is considered to be an important marker for the progression of chronic kidney disease. More recently, proteinuria has been reported to be a consequence of SRL therapy,12 although the mechanism is still not clear. Other information has indicated that proteinuria may be partially reversed following SRL dose reduction.13 Also, there is evidence that conversion from SRL to MMF in the face of stable therapy with tacrolimus leads to a significant reduction in proteinuria14 and finally that patients treated with de novo SRL-based immunosuppression suffer kidney tubular/parietal epithelial cell and podocyte apoptosis, which may explain, in part at least, the origin of the proteinuria.15 No significant correlation was observed between the development of proteinuria and the SRL dose or blood level. However, in the 3 patients (8.3%) who had SRL withdrawn we observed reversion of proteinuria and edema, strongly suggesting that SRL had a direct effect to induce proteinuria. Triptolide is a potent immunosuppressive ingredient of diterpenoid from T. wilfordii Hook F. In recent years, there has been considerable interest in the application of Tripterygium and its main bioactive constituent, the diterpene triepoxide triptolide,11 to treat a variety of autoimmune diseases, such as rheumatoid arthritis, nephritis, and systemic lupus erythematosus.12,13 It is being tried as an immunosuppressant in organ transplantation.16 Triptolide may reduce proteinuria, alleviate glomerular immune injuries, and also remarkably improve the podocyte lesion necessary to restore the normal structure of slit diaphragm. Our results indicated that recovery of the expression and distribution of nephrin and podocin, along with the improvement in podocyte foot process effacement, contributed to the reduction in proteinuria among patients with Heymann nephritis treated with triptolide. The therapeutic effect of triptolide might be due to its direct activity on treatment with podocyte injuries.17 Triptolide stabilizes cytoskeleton filaments and increases nephrin and podocin production on podocytes. However, the results of the current study showed that triptolide not only provided direct protection of podocytes against puromycin aminonucleoside (PAN)-induced injury, but also enhanced recovery from prior podocyte injury. The results also showed that triptolide has profound effects on podocytes in vitro and in vivo. The main mode of action of triptolide18 is inhibition of expression of proinflammatory genes, such as those for interleukin-2 (IL-2), inducible nitric oxide synthase (iNOS),
3477
tumor necrosis factor-alpha (TNF-alpha), cyclooxygenase-2 (COX-2), and interferon-gamma (IFN-gamma). The protective effect of triptolide may partially contribute to the restoration of myosin phosphatase activity mediated by Rho kinase. The antiproteinuria effect of triptolide observed in vivo may be due, at least in part, to its direct effects on podocytes.19 More research is needed to investigate triptolide as a potential future therapy for patients with podocyte diseases.
REFERENCES 1. Oldakowska-Jedynak U, Paczek L, Mucha K, et al: Successful reversal of acute vascular rejection and cyclosporine-associated nephrotoxicity in renal allograft with combined sirolimus and mycophenolate mofetil as immunotherapy. Transplant Proc 38:66, 2006 2. Webster AC, Lee VWS, Chapman JR, et al: Target of rapamycin inhibitors (sirolimus and everolimus) for primary immunosuppression of renal transplant recipients: a systematic review and meta-analysis of randomized trials. Transplantation 81:1234, 2006 3. Ciancio G, Burke GW, Gaynor JJ, et al: A randomized long-term trial of tacrolimus/sirolimus versus tacrolimums/mycophenolate versus cyclosporine/sirolimus in renal transplantation: three-year analysis. Transplantation 81:845, 2006 4. Watson JE, Firth J, Williams PF, et al: A randomized controlled trial of late conversion from CNI-based to sirolimus based immunosuppression following renal transplantation. Am J Transplant 5:2496, 2005 5. van der Akker JM, Wetzels JFM, Hoitsma AJ: Proteinuria following conversion from azathioprine to sirolimus in renal transplant recipients. Kidney Int 70:1355, 2006 6. Boratynska M, Banasik M, Watorek E, et al: Conversion to sirolimus from cyclosporine may induce nephrotic proteinuria and progressive deterioration of renal function in chronic allograft nephropathy patients. Transplant Proc 38:101, 2006 7. Tao X, Sun Y, Dong Y, et al: A prospective, controlled, double-blind, cross-over study of Tripterygium wilfordii Hook F. in the treatment of rheumatoid arthritis. Chin Med J Engl 102:327, 1989 8. Qin WZ, Liu CH, Yang SM: Tripterygium wilfordii Hook F. in systemic lupus erythematosus. Chin Med J 94:827, 1981 9. Hu W, Tang Z, Yao X, et al: Double dosage of Tripterygium wilfordii Hook F. in treating nephritic syndrome: a prospective clinical trial. J Nephrol Dial Transplant 6:210, 1997 10. Zheng J: Screening of active anti-inflammatory, immunosuppressive and antifertility components of Tripterygium wilfordii. III. A comparison of the antiinflammatory and immunosuppressive activities of 7 diterpene lactone epoxide compounds in vivo. Acta Acad Med Sinicae 13:391, 1991 11. Chen BJ: Triptolide, a novel immunosuppressive and antiinflammatory agent purified from a Chinese herb Tripterygium wilfordii Hook F. Leukemia Lymphoma 42:253, 2001 12. Izzedine H, Brocheriou I, Frances C, et al: Posttransplantation proteinuria and sirolimus. N Engl J Med 353:2088, 2005 13. Letavernier E, Pèraldi MN, Pariente A, et al: Proteinuria following a switch from calcineurin inhibitors to sirolimus. Transplantation 80:1198, 2005 14. Augustine JJ, Chang PC, Klaus TC, et al: Improved renal function after conversion from tacrolimus/sirolimus to tacrolimus/ mycophenolate mofetil in renal transplant recipients. Transplantation 81:1004, 2006 15. Straathof-Galema L, Wetzels JF, Dijkman HB, et al: Sirolimus-associated heavy proteinuria in a renal transplant
3478 recipient: evidence for a tubular mechanism. Am J Transplant 69:429, 2006 16. Ji SM, Wang QW, Chen JS, et al: Clinical trial of Tripterygium wilfordii Hook F. in human kidney transplantation in China. Transplant Proc 38:1274, 2006 17. Qin WS, Liu ZH, Zeng CH, et al: Therapeutic effect of triptolide on podocyte injury in passive Heymann nephritis. J Nephrol Dial Transplant 16:101, 2007
JI, LI, WEN ET AL 18. Liu Q, Chen T, Chen G, et al: Immunosuppressant triptolide inhibits dendritic cell-mediated chemoattraction of neutrophils and T cells through inhibiting Stat-phosphorylation and NFB activation. Biochem Biophys Res Commun 345:1122, 2006 19. Chen ZH, Liu ZH, Sun H, et al: Triptolide ameliorates podocyte injury induced by puromycin aminonucleoside in vitro. J Nephrol Dial Transplant 16:119, 2007
S
IROLIMUS (SRL) is a potent immunosuppressive drug used for the prevention of acute allograft rejection after renal transplantation.1 SRL regimens have been either as a de novo immunosuppressive protocol or in a conversion protocol from calcineurin inhibitors (CNI) to SRL.2– 4 Nevertheless, the occurrence of proteinuria has recently been recognized among patients on SRL-based therapy,5,6 an adverse event that affects deterioration of long-term renal function. Tripterygium wilfordii Hook F., called T II, has been used as an insecticide for many centuries in traditional Chinese medicine. Only in the past 20 years has it been used to treat a variety of autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus, with promising results.7,8 It was first used in the treatment of glomerular disease by a group of workers from Jinling Hospital in 1997.9 The chemistry of the plant has been studied: 15 alkaloids, 15 triterpenoids, and 12 diterpenoids have been isolated from the plant, among which diterpenoids are believed to be the most important useful compounds for nephrological practice.10 We pioneered a therapeutic trial of T II in glomerular disease. Triptolide, an active fraction purified from an extract of T. wilfordii, increased the
remission rates of nephritic proteinuria, including IgA nephritis, IgM nephritis, and mesangial proliferative glomerulonephritis (MsPGN).9,11 The purpose of this study was to investigate the therapeutic effects of T. wilfordii Hook F. on proteinuria associated with SRL among renal transplant recipients. PATIENTS AND METHODS Patient Population Among 124 cadaveric renal allograft recipients transplanted between April 2001 and November 2006, we enrolled 36 patients (24 males and 12 females) of ages ranging from 22 to 48 years due to severe proteinuria caused by SRL prescribed either as a de novo immunosuppressant or in a conversion protocol. Proteinuria was diagnosed by 24-hour urine collections performed routinely or when patients showed edema or when detected on urinalysis. From the Research Institute of Nephrology (S.M.J., J.Q.W., G.Z.S., Z.C., D.R.C., J.S.C.), Department of Nephropathy, Jinling Hospital, Nanjing, China, and Nanjing University School of Medicine (L.S.L., Z.H.L.), Nanjing, China. Address reprint requests to Dr Lei-shi Li, Research Institute of Nephrology, Jinling Hospital, 305 East Zhong Shan Road, Nanjing 210002, China. E-mail: [email protected]
0041-1345/08/$–see front matter doi:10.1016/j.transproceed.2008.07.140
© 2008 by Elsevier Inc. All rights reserved. 360 Park Avenue South, New York, NY 10010-1710
3474
Transplantation Proceedings, 40, 3474 –3478 (2008)
EFFECT OF TRIPTERYGIUM ON PROTEINURIA
3475
Thirty-six patients developed proteinuria (⬎1.5 g/24 h) on SRL for 1 to 6 months. Only 6/31 patients (19.4%) receiving SRL de novo developed proteinuria, and 30 patients (30/93; 32.3%) displayed proteinuria after abrupt cessation of a CNI. The mean value of proteinuria was 4.4 ⫾ 2.9 g/24 h (range, 1.5–7.3 g/24 h). Patients presenting any degree of proteinuria before conversion to SRL were not enrolled in the study. Only patients who developed de novo proteinuria after SRL were included in this analysis. Primary diseases included chronic glomerulonephritis (n ⫽ 26; 72.2%), hypertensive nephropathy (n ⫽ 2; 5.6%), polycystic kidney disease (n ⫽ 2; 5.6%), purpuric nephritis (n ⫽ 2; 5.6%), lupus nephritis (n ⫽ 2; 5.6%), and gouty nephropathy (n ⫽ 2; 5.6%).
Study Design Patients were randomly assigned to treatment with T II (T II group; n ⫽ 21) or without T II (valsartan group; n ⫽ 15) for 12 months. There was no significant difference between the 2 groups in sex, age, mean blood pressure serum albumin level, hemoglobin, fasting blood glucose, proteinuria, levels of serum creatinine (SCr) and serum total cholesterol (TC), and triglycerides (TG). There also was no significant difference between the 2 groups in mean daily dosage of mycophenolate mofetil (MMF), MMF AUC 0 –12, cyclosporine, or tacrolimus before enrollment. Hypertension was defined as a diastolic blood pressure (DBP) ⬎90 mm Hg and/or a systolic blood pressure (SBP) ⬎140 mm Hg at 2 or more visits. The study was approved by our ethics committee; all patients gave written informed consent.
Dosage of T II T II (1 mg/kg/d) was continued over 1 year. Tripterygium wilfordii Hook F. was provided by Mei-Tong Pharmaceutical Ltd (TaiZhou, China) as a 10 mg triptolide. During the overall clinical follow-up, all patients did not use angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB). Patients with hypertension were given calcium channel antagonists, -receptor blockers, ␣-receptor blockers, and/or loop diuretics to control blood pressure at 120/80 mm Hg.
Dosage of Valsartan Patients who continued to meet the eligibility criteria were administered open-label valsartan (Beijing Novartis Pharma Ltd) in an
initial dosage of 80 mg/d, force titrated to 80 mg twice per day after 1 week. Treatment with valsartan was continued for 12 months. When necessary, the doses of other antihypertensive medications were altered to maintain the goal blood pressure of 120/80 mm Hg.
Immunosuppressive Protocol These patients underwent abrupt cessation of cyclosporine or tacrolimus the evening before and SRL (Rapamune, Wyeth) addition the following morning as a first dose of 6 mg orally, thereafter, a maintenance dosage of 2 mg/d. The SRL doses were adjusted to obtain trough blood levels in the range of 6 to 10 ng/mL (ELISA method). SRL trough blood levels were monitored 7 days after conversion, every week for the first month, every 2 weeks for the second and third months, then monthly thereafter. After conversion, MMF (Cell Cept, Roche Pharmaceutical Co, Ltd), 750 mg twice per day, was adjusted by AUC 0 –12 to be maintained at 35 to 45 mg/h/L. In both groups, steroid therapy was unchanged.
Evaluation of Efficiency Complete remission: proteinuria decreased by ⬎50%; partial remission: proteinuria decreased by 20% to 50%; ineffective: proteinuria decreased by ⬍20%.
Statistical Analysis We used JMP software version 6.0 (SAS Institute Inc, Cary, NC, United States) for statistical analysis. For categorical data, the Fisher exact test or Pearson chi-square test was used. Parametric continuous data were analyzed by Student t tests. For nonparametric continuous data, we employed Wilcoxon rank-sum tests. P ⬍ .05 (2-sided) was considered significant.
RESULTS Baseline Characteristics
The patients’ clinical and laboratory data during the 12month follow-up are summarized in Table 1. SBP and DBP remained stable for the T II treatment study period: SBP 137.1 ⫾ 26.4 vs 127.8 ⫾ 24.3 mm Hg and DBP 89.2 ⫾ 4.3 vs 83.4 ⫾ 4.9 mm Hg (P ⫽ .87). SBP fell from 139.8 ⫾ 6.2 to 128.2 ⫾ 6.0 mm Hg and DBP 84.2 ⫾ 4.3 to 82.4 ⫾ 4.9 mm Hg (P ⫽ .84) by the end of the 12 months of valsartan
Table 1. Clinical and Laboratory Data T II Group (n ⫽ 21)
SBP (mm Hg) DBP (mm Hg) Mean proteinuria level (g/24 h) Serum albumin level (g/L) Hemoglobin level (g/L) Blood glucose (mmol/L) Total cholesterol (mmol/L) Serum triglyceride (mmol/L) Serum creatinine (mg/dL) Serum potassium (mmol/L) *P ⬍ .05, 12 months vs baseline. † P ⬍ .001, 12 months vs baseline.
Valsartan Group (n ⫽ 15)
Baseline
12 Months
Baseline
12 Months
137.1 ⫾ 26.4 89.2 ⫾ 4.3 4.4 ⫾ 2.9 36.4 ⫾ 2.9 13.1 ⫾ 2.2 5.5 ⫾ 1.0 6.6 ⫾ 1.2 3.1 ⫾ 1.0 1.6 ⫾ 0.5 4.3 ⫾ 0.1
127.8 ⫾ 24.3 83.4 ⫾ 4.9 0.9 ⫾ 0.2† 41.1 ⫾ 1.2* 12.1 ⫾ 2.2 5.4 ⫾ 1.1 5.5 ⫾ 2.1* 2.5 ⫾ 1.4* 1.2 ⫾ 0.4* 4.2 ⫾ 0.2
139.8 ⫾ 6.2 84.2 ⫾ 4.3 4.3 ⫾ 2.7 36.8 ⫾ 3.0 13.3 ⫾ 3.2 5.0 ⫾ 1.1 6.5 ⫾ 2.1 2.9 ⫾ 1.3 1.6 ⫾ 0.3 4.1 ⫾ 0.5
128.2 ⫾ 6.0 82.4 ⫾ 4.9 1.6 ⫾ 0.5† 37.9 ⫾ 4.2 11.3 ⫾ 3.2 4.4 ⫾ 1.9 6.9 ⫾ 1.1 2.0 ⫾ 1.3 2.1 ⫾ 0.5* 4.9 ⫾ 1.3
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JI, LI, WEN ET AL
therapy, but remained stable thereafter. However, the mean proteinuria level in the T II group was significantly lower than the valsartan group (P ⬍ .001). The serum albumin level in the T II group was significantly higher than the valsartan group (41.1 ⫾ 1.2 vs 37.9 ⫾ 4.2 g/L; P ⬍ .05). The serum hemoglobin level in the T II group was higher than the valsartan group (12.1 ⫾ 2.2 vs 11.3 ⫾ 3.2 g/L). There was no significant difference in fasting blood glucose: 5.4 ⫾ 1.1 vs 4.4 ⫾ 1.9 mmol/L (P ⫽ .81). TC and TG levels in the T II group were significantly lower than the valsartan group (P ⬍ .05). In the valsartan group, blood TC and TG levels did not clearly change and even showed an increasing tendency, namely, 6.5 ⫾ 2.1 vs 6.9 ⫾ 1.1 and 2.0 ⫾ 1.3 vs 2.9 ⫾ 1.3 mmol/L, respectively. As for the mean SCr at 3, 6, and 12 months follow-up, each value among the T II group was lower than that of the valsartan group (1.6 ⫾ 0.5 vs 1.6 ⫾ 0.3, 1.5 ⫾ 0.3 vs 1.8 ⫾ 0.5, and 1.2 ⫾ 0.4 vs 2.1 ⫾ 0.5 mg/dL; P ⬍ .05). Efficiency
At 12 months, the total effective rates in the T II group and the valsartan group were respectively 95.2% and 86.7% (P ⬍ .05; Table 2), and the ineffective rates 4.8% versus 13.3% (P ⬍ .001). However, 3 cases occurred in the ineffective group: 1 case in the T II group and 2 cases in the valsartan group. When the 3 patients (8.3%) had SRL withdrawn, we observed reversion of proteinuria and edema upon conversion to tacrolimus at 3, 3, or 6 months after conversion to SRL.
Time follow-up (months) (%)
W W TXW
X
Y
Z
[
\
]
}GGOGdGXZP {G p p G G G G GOGdGYWP
TYW TZW
P<0.001
T[W T\W T]W T^W
Fig 1.
Decreased extent of proteinuria in the 2 groups.
Dosage of SRL at Time of Proteinuria
There was no significant difference between the 2 groups in mean MMF AUC 0 –12 or SRL trough blood levels: 45 ⫾ 3.5 vs 46 ⫾ 3 mg/h/L and 5.8 ⫾ 0.4 vs 5.9 ⫾ 0.3 g/L, respectively. The dosage of SRL at the time of proteinuria ranged from 1.5 to 7.3 mg/24 h (mean, 4.4 ⫾ 2.9 g/24 h), with SRL trough blood levels ranging from 5.4 to 10.3 ng/mL (mean, 6.4 ⫾ 0.7 ng/mL). There was no correlation between proteinuria levels and SRL dosage (r ⫽ .44; P ⫽ NS), or SRL trough blood levels (r ⫽ .27; P ⫽ NS). All patients were followed for 12.2 (⫾3.7) months after treatment. There were no rejection episodes during the 12month follow-up. Adverse Events
Decreased Extent of Proteinuria
The 2 levels of proteinuria dropped in the 2 groups, but the decreased extent of proteinuria was more obvious in the T II group than the valsartan group (Fig 1). Mean proteinuria was 4.2 ⫾ 1.7 g/d at baseline in the T II group and fell to 0.9 ⫾ 0.2 g/d at the end of the study. Twenty of 21 patients with proteinuria in the T II group were negative at 3-month follow-up with disappearance edema. Patients in the valsartan group also showed decreased proteinuria, but none of them were negative, and the SCr level was constantly rising. Two patients developed kidney graft insufficiency with SCr levels of 4.0 mg/dL, and accompanying hyperkalemia, requiring patient to return to hemodialysis therapy after 9 months.
Table 2. Comparison of Efficiency Between the 2 Groups
Complete remission, n (%) Partial remission, n (%) Ineffective, n (%) Total effective rate (%)
T II Group (n ⫽ 21)
Valsartan Group (n ⫽ 15)
P
16 (76.2) 4 (19.0) 1 (4.8) 95.2
8 (53.3) 5 (33.3) 2 (13.3) 86.7
⬍.001 ⬍.05 ⬍.001 ⬍.001
All patients tolerated T II over the 12 months of this study. However, there were some adverse events that had greater incidence rates in the valsartan group compared with the T II group, namely, hyperkalemia (26.7% vs 4.8%). The mean serum potassium trended upward during valsartan treatment from 4.1 ⫾ 0.5 to 4.9 ⫾ 1.3 mmol/L. In 2 patients there was a need to reduce or discontinue valsartan therapy because of persistent hyperkalemia (serum potassium ⬎6.0 mmol/L). Other adverse events included cough (26.6% vs 0%), numbness (6.7% vs 0%), dry mouth (13.3% vs 0%), fatigue (26.6% vs 4.8%), headache (26.6% vs 0%), and sore throat (33.3% vs 4.8%). The incidences of herpes simplex (13.3% vs 0%), cutaneous herpes zoster infections (0% vs 0%), leukopenia (6.7% vs 0%), liver dysfunction (6.7% vs 0%), and gastrointestinal events (13.3% vs 4.8%) beween the 2 groups showed obvious differences. DISCUSSION
The present study suggested that heavy proteinuria was observed in 29.0% of patients receiving SRL-based immunosuppression at our center, developing prominently in the first 3 months after the initiation of SRL. Herein we have evaluated the safety and efficacy on proteinuria associated with SRL in renal transplant patients, comparing Triptery-
EFFECT OF TRIPTERYGIUM ON PROTEINURIA
gium with a valsartan-based immunosuppressive regimen in renal transplant recipients. Our results from this follow-up study demonstrated that the levels of proteinuria dropped in the 2 groups; the total effective rates in the T II and the valsartan groups were 95.2% and 86.7%, respectively. The side effects were minimal in the T II group. However, increased hyperkalemia occurred in 2/10 patients in the valsartan group, requiring interruption or cessation of valsartan therapy. This study suggested that the application of T II showed greater effects than valsartan to reduce proteinuria associated with SRL in renal transplant patients. Proteinuria is considered to be an important marker for the progression of chronic kidney disease. More recently, proteinuria has been reported to be a consequence of SRL therapy,12 although the mechanism is still not clear. Other information has indicated that proteinuria may be partially reversed following SRL dose reduction.13 Also, there is evidence that conversion from SRL to MMF in the face of stable therapy with tacrolimus leads to a significant reduction in proteinuria14 and finally that patients treated with de novo SRL-based immunosuppression suffer kidney tubular/parietal epithelial cell and podocyte apoptosis, which may explain, in part at least, the origin of the proteinuria.15 No significant correlation was observed between the development of proteinuria and the SRL dose or blood level. However, in the 3 patients (8.3%) who had SRL withdrawn we observed reversion of proteinuria and edema, strongly suggesting that SRL had a direct effect to induce proteinuria. Triptolide is a potent immunosuppressive ingredient of diterpenoid from T. wilfordii Hook F. In recent years, there has been considerable interest in the application of Tripterygium and its main bioactive constituent, the diterpene triepoxide triptolide,11 to treat a variety of autoimmune diseases, such as rheumatoid arthritis, nephritis, and systemic lupus erythematosus.12,13 It is being tried as an immunosuppressant in organ transplantation.16 Triptolide may reduce proteinuria, alleviate glomerular immune injuries, and also remarkably improve the podocyte lesion necessary to restore the normal structure of slit diaphragm. Our results indicated that recovery of the expression and distribution of nephrin and podocin, along with the improvement in podocyte foot process effacement, contributed to the reduction in proteinuria among patients with Heymann nephritis treated with triptolide. The therapeutic effect of triptolide might be due to its direct activity on treatment with podocyte injuries.17 Triptolide stabilizes cytoskeleton filaments and increases nephrin and podocin production on podocytes. However, the results of the current study showed that triptolide not only provided direct protection of podocytes against puromycin aminonucleoside (PAN)-induced injury, but also enhanced recovery from prior podocyte injury. The results also showed that triptolide has profound effects on podocytes in vitro and in vivo. The main mode of action of triptolide18 is inhibition of expression of proinflammatory genes, such as those for interleukin-2 (IL-2), inducible nitric oxide synthase (iNOS),
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tumor necrosis factor-alpha (TNF-alpha), cyclooxygenase-2 (COX-2), and interferon-gamma (IFN-gamma). The protective effect of triptolide may partially contribute to the restoration of myosin phosphatase activity mediated by Rho kinase. The antiproteinuria effect of triptolide observed in vivo may be due, at least in part, to its direct effects on podocytes.19 More research is needed to investigate triptolide as a potential future therapy for patients with podocyte diseases.
REFERENCES 1. Oldakowska-Jedynak U, Paczek L, Mucha K, et al: Successful reversal of acute vascular rejection and cyclosporine-associated nephrotoxicity in renal allograft with combined sirolimus and mycophenolate mofetil as immunotherapy. Transplant Proc 38:66, 2006 2. Webster AC, Lee VWS, Chapman JR, et al: Target of rapamycin inhibitors (sirolimus and everolimus) for primary immunosuppression of renal transplant recipients: a systematic review and meta-analysis of randomized trials. Transplantation 81:1234, 2006 3. Ciancio G, Burke GW, Gaynor JJ, et al: A randomized long-term trial of tacrolimus/sirolimus versus tacrolimums/mycophenolate versus cyclosporine/sirolimus in renal transplantation: three-year analysis. Transplantation 81:845, 2006 4. Watson JE, Firth J, Williams PF, et al: A randomized controlled trial of late conversion from CNI-based to sirolimus based immunosuppression following renal transplantation. Am J Transplant 5:2496, 2005 5. van der Akker JM, Wetzels JFM, Hoitsma AJ: Proteinuria following conversion from azathioprine to sirolimus in renal transplant recipients. Kidney Int 70:1355, 2006 6. Boratynska M, Banasik M, Watorek E, et al: Conversion to sirolimus from cyclosporine may induce nephrotic proteinuria and progressive deterioration of renal function in chronic allograft nephropathy patients. Transplant Proc 38:101, 2006 7. Tao X, Sun Y, Dong Y, et al: A prospective, controlled, double-blind, cross-over study of Tripterygium wilfordii Hook F. in the treatment of rheumatoid arthritis. Chin Med J Engl 102:327, 1989 8. Qin WZ, Liu CH, Yang SM: Tripterygium wilfordii Hook F. in systemic lupus erythematosus. Chin Med J 94:827, 1981 9. Hu W, Tang Z, Yao X, et al: Double dosage of Tripterygium wilfordii Hook F. in treating nephritic syndrome: a prospective clinical trial. J Nephrol Dial Transplant 6:210, 1997 10. Zheng J: Screening of active anti-inflammatory, immunosuppressive and antifertility components of Tripterygium wilfordii. III. A comparison of the antiinflammatory and immunosuppressive activities of 7 diterpene lactone epoxide compounds in vivo. Acta Acad Med Sinicae 13:391, 1991 11. Chen BJ: Triptolide, a novel immunosuppressive and antiinflammatory agent purified from a Chinese herb Tripterygium wilfordii Hook F. Leukemia Lymphoma 42:253, 2001 12. Izzedine H, Brocheriou I, Frances C, et al: Posttransplantation proteinuria and sirolimus. N Engl J Med 353:2088, 2005 13. Letavernier E, Pèraldi MN, Pariente A, et al: Proteinuria following a switch from calcineurin inhibitors to sirolimus. Transplantation 80:1198, 2005 14. Augustine JJ, Chang PC, Klaus TC, et al: Improved renal function after conversion from tacrolimus/sirolimus to tacrolimus/ mycophenolate mofetil in renal transplant recipients. Transplantation 81:1004, 2006 15. Straathof-Galema L, Wetzels JF, Dijkman HB, et al: Sirolimus-associated heavy proteinuria in a renal transplant
3478 recipient: evidence for a tubular mechanism. Am J Transplant 69:429, 2006 16. Ji SM, Wang QW, Chen JS, et al: Clinical trial of Tripterygium wilfordii Hook F. in human kidney transplantation in China. Transplant Proc 38:1274, 2006 17. Qin WS, Liu ZH, Zeng CH, et al: Therapeutic effect of triptolide on podocyte injury in passive Heymann nephritis. J Nephrol Dial Transplant 16:101, 2007
JI, LI, WEN ET AL 18. Liu Q, Chen T, Chen G, et al: Immunosuppressant triptolide inhibits dendritic cell-mediated chemoattraction of neutrophils and T cells through inhibiting Stat-phosphorylation and NFB activation. Biochem Biophys Res Commun 345:1122, 2006 19. Chen ZH, Liu ZH, Sun H, et al: Triptolide ameliorates podocyte injury induced by puromycin aminonucleoside in vitro. J Nephrol Dial Transplant 16:119, 2007