The effect of alfuzosin on renal resistive index,urinary electrolytes and β2 microglobulin levels and TGF β-1 levels of kidney tissue in rats with unilateral ureteropelvic junction obstruction

Background: In this study, it was aimed to determine the effects of alfuzosin on experimentally generated unilateral partial ureteropelvic junction obstruction (UPO) in rats.

Materials and methods: Thirty Long–Evans rats were randomly allocated into five groups. In control group (C), nothing was performed; in group Sham (S) only laparotomy was done; in Alfuzosin group (A) only alfuzosin was administered for two weeks (10?mg/kg/day p.o.) without any surgery; in UPO group, unilateral UP junction obstruction was produced; and in the Group UPT (ureteropelvic obstruction?+?treatment), alfuzosin was administered for two weeks (10?mg/kg/day p.o.) in addition to UPO production. Renal pelvic anteroposterior diameters were determined with ultrasonography (USG) and renal arterial resistivity indexes by color Doppler USG. Urine was collected both at the beginning and at the end of the experiment for 24?h in all the groups and at the end of the experiment, blood samples were obtained. Blood and urine electrolytes and TGF-β1, urine density, urine β₂ microglobulin levels were determined. Renal tissue samples harvested from all of the rats were histopathologically evaluated. Results were determined using one-way ANOVA t-test; p?<?0.05 was accepted as significant.

Results: Urine density in the UPT group was lower with respect to UPO group and blood electrolytes were preserved as close to normal (p?<?0.05). In the UPT group, urine TGF-β1 and blood TGF-β1, blood β₂ microglobulin levels and histopathologic damage scores were lower compared to the UPO group (p?<?0.05).

Conclusion: It is shown in this experimental unilateral partial UPO model that alfuzosin treatment prevents obstructive renal damage.     

Advanced IgA nephropathy with impaired renal function benefits from losartan treatment in rats

Abstract

Background: Treatment with angiotensin receptor blockers (ARBs) is successful in mitigating IgA nephropathy (IgAN), independent of blood pressure changes, but the therapeutic role of ARB in advanced IgAN with impaired renal function is to be ascertained. The present study was performed to investigate the effect of losartan on advanced IgAN induced by staphylococcal enterotoxin B (SEB) combined with 5/6 nephrectomy in rats. Methods: Fifty-four male SD rats were randomly divided into three group: Rats in the model group were treated with SEB plus 5/6 nephrectomy, and those in the losartan group were gavaged with losartan (33.3?mg?kg^?1?d^?1) besides the treatment with SEB plus 5/6 nephrectomy. The urine and blood biochemical changes of rats were tested. IgA, IgG, IgM and C3 depositions were studied dynamically with immunofluorescence. The renal tissue structures were observed under light microscopy. The expressions of TGF-β1, FN, alpha-SMA and FGF-1 in rat renal tissues were determined with immunohistochemical methods and real-time PCR. Results: At 12 weeks, rats with SEB treatment plus 5/6 nephrectomy showed gradually increased urinary red blood cell (URBC) with a gradual elevation of the 24?h urinary protein, serum BUN and Scr, but losartan treatment lowered the levels of 24?h urinary protein, serum BUN and Scr. A large number of IgA depositions in the mesangial area, glomerulosclerosis and tubulointerstitial fibrosis were found in the model group, and the losartan group showed relieved injury. The expressions of TGF-β1, FN, alpha-SMA and FGF-1 were significantly elevated in the model. Losartan lessened their expressions. Conclusion: Losartan treatment can delay the progression of advanced IgA nephropathy with impaired renal function.     

Atorvastatin attenuates experimental contrast-induced acute kidney injury: a role for TLR4/MyD88 signaling pathway

Objectives: To investigate the protective effect of different atorvastatin doses on contrast-induced acute kidney injury and the related mechanism.

Methods: Healthy male Sprague–Dawley (SD) rats were randomly divided into the blank control group, experimental control group and different-dose atorvastatin groups. A rat model of contrast-induced acute kidney injury was established. We detected changes in serum creatinine (Scr) and blood urea nitrogen (BUN) before and after model establishment, observed and scored renal tubular injury, analyzed rat renal cell apoptosis, and measure the expression of signal pathway proteins and downstream inflammatory factors.

Results: After contrast agent injection, the Scr and BUN levels of the experimental control group were significantly increased, the different doses applied in the atorvastatin group significantly reduced the Scr and BUN levels (p?p?p?p?Conclusion: Different atorvastatin doses have protective effects on contrast-induced acute renal tubular injury in rats, possibly by targeting TLR4, suppressing TLR4 expression, regulating the TLR4/Myd88 signaling pathway, and inhibiting the expression of downstream inflammatory factors.     

益肾泄浊方在大鼠5／6肾切除模型中抗肾间质纤维化的作用

目的观察益肾泄浊方对大鼠5／6肾切除模型肾间质纤维化的影响。方法将50只SD大鼠随机分为假手术组（A组）、手术组（B组）、中药治疗组（造模后给予益肾泻浊方10ml／kg灌胃,C组）、缬沙坦治疗组（造模后给予缬沙坦10mg／kg灌胃,D组）以及中药＋缬沙坦治疗组（造模后给予益肾泻浊方10ml／kg＋缬沙坦10mg／kg灌胃,E组）,每组各10只。干预16周后,检测24h尿蛋白、肾功能,予肾脏组织Masson染色行肾间质纤维化评分;RT-PCR检测肾脏TGF-β1、I型胶原、FNmRNA的表达。结果与A组相比,B组大鼠的肾功能指标、尿蛋白水平、肾问质纤维化评分、TGF-β1、I型胶原、FN的表达均明显增加（P〈O．01）。各干预组较B组以上各指标均显著下降（P〈0．01）,E组指标下降更明显（P〈0．01）。结论益肾泻浊方能有效减缓5／6肾切除大鼠模型的肾脏纤维化进展;其抗纤维化机制可能与抑制肾脏TGF-β1的表达,降低I型胶原、FN的沉积有关。     

Metformin alleviated EMT and fibrosis after renal ischemia–reperfusion injury in rats

Purpose The purpose of this study is to assess the potential effects of metformin on the development of EMT and tubulointerstitial fibrosis 12 weeks after acute renal ischemia–reperfusion. Methods Male Sprague–Dawley rats were randomly assigned to four groups: Sham, IRI, transient administration of metformin (TAM), and continuous administration of metformin (CAM). Metformin was administered i.p. at a dose of 125?μg kg?^??1 d^???1 3 d prior to suffering from IRI (TAM), or from 3 d before suffering from IRI to 12 weeks after reperfusion (CAM). Renal function, histology, and expressions of IL-6, TNF-α, α-SMA, TGF-β1, Vimentin, and E-cadherin were analyzed. Results Tubulointerstitial fibrosis worsened further in IRI, accompanied by the increased expressions of interleukin-6, TNF-α, α-SMA, TGF-β1, Vimentin, and loss of E-cadherin. Although there were no significant differences between IRI and TAM (p?>?0.05). Compared with the IRI, expressions of IL-6, TNF-α, α-SMA, TGF-β1, and Vimentin were reduced and the expression of E-cadherin was restored in CAM (p?0.05). CAM also significantly promoted activation of AMPK (p?0.05), which showed no difference among Sham, IRI, and TAM (p?>?0.05). Conclusions CAM significantly attenuated tubulointerstitial fibrosis and EMT in rats, potentially via activation of AMPK and down-regulation of TGF-β1.     

TGF-β1及FN在狼疮样小鼠肾组织中的表达及霉酚酸酯的干预作用

目的：研究TGF-β1及FN在狼疮样小鼠肾组织中的表达及霉酚酸酯（MMF）的干预作用。方法：建立cGVHD狼疮样小鼠模型。按随机设计原则将模型动物分两组即模型组和MMF治疗组,另设正常对照组。检测各组小鼠血肌酐、尿素氮及尿蛋白的变化,用HE染色观察肾组织纤维化程度,以Real-time PCR检测各组小鼠肾组织中TGF-β1及FN的mRNA丰度,并用Western blotting方法检测各组小鼠肾组织中TGF-β1及FN的蛋白表达情况。结果：12周模型组的小鼠肾小球系膜节段、弥漫性增生,且血肌酐、尿素氮及尿蛋白较正常对照组均明显增加,Real-timePCR及Western blotting结果证实模型组小鼠的肾组织中TGF-β1及FN的mRNA和蛋白表达水平与正常组相比水平均明显增加,而MMF治疗组与模型组相比其TGF-β1及FN的mRNA和蛋白表达均降低,且血肌酐、尿素氮及尿蛋白水平也有所降低。结论：TGF-β1可能参与了狼疮肾炎的发病,MMF可能通过抑制肾组织TGF-β1的表达来改善狼疮肾炎的增生病变。     

益肾泄浊方对TGF-β_1诱导大鼠肾小管上皮细胞Ⅰ型胶原及FN表达的影响

目的：探讨益肾泄浊方对TGF-β1诱导大鼠肾小管上皮细胞Ⅰ型胶原及FN表达的影响。方法：采用灌胃法分别给予健康大鼠益肾泻浊方冲剂、缬沙坦以及益肾泻浊方＋缬沙坦联合治疗,取给药后大鼠的血清分组干预经TGF-β1刺激72h后的大鼠肾小管上皮（NRK52E）细胞,用RT-PCR方法检测Ⅰ型胶原、FNmRNA的表达,用ELISA方法检测FN蛋白水平的表达。结果：益肾泻浊方、缬沙坦均能抑制TGF-β1诱导的NRK52EⅠ型胶原、FN的表达,而益肾泻浊方与缬沙坦联用后,对NRK52E细胞FN表达的抑制作用更为显著。结论：益肾泻浊方抑制TGF-β1诱导大鼠肾小管上皮细胞Ⅰ型胶原及FN的表达,可延缓肾脏纤维化的进展。     

黄芪对人肾小管上皮细胞细胞外基质分泌的影响及其机制探讨

目的：探讨黄芪对人肾小管上皮细胞细胞外基质分泌的影响及甚可能机制。方法：将体外培养的人肾小管上皮（HK-2）细胞株转板至细胞融合并同步后,分为空白对照组、转化生长因子-β（TGF-β1）刺激组（5ng／ml）、TGF-β1加黄芪100μg／ml组、TGF-β1加黄芪1mg／ml组。作用24h后半定量逆转录多聚酶链反应（RT—PCR）检测纤维连接蛋白（FN）及纤溶酶原激活物抑制剂-1（PAI-1）mRNA;酶联免疫吸附试验（ELISA）法检测上清液中FN的含量;westernblot检测PAI-1的表达。结果：（1）HK-2细胞表达少量FN和PAI-1;（2）HK-2细胞在5ng／ml TGF-β1．刺激下分泌FN、PAI—1mRNA及FN、PAI-1蛋白表达明显增加,与空白对照组比较差异有统计学意义（P〈0．01）;（3）HK-2细胞在TGF-β1和不同浓度的黄芪作用后,可使FN、PAI-1mRNA及蛋白表达减少,与TGF-β1组比较差异有统计学意义（P〈0．01）,尤以黄芪1mg／mi组为甚。结论：TGF—β1可促进HK-2细胞分泌FN和PAI—1,黄芪可部分拮抗TGF-β1的上述效应。这可能是黄芪预防或改善肾小管间质病变的作用机制之一。     

The effect of simvastatin and erythropoietin on renal fibrosis in rats with unilateral ureteral obstruction

Prevention of fibrosis is a very important therapeutic strategy in the treatment of obstructive nephropathy (ON). The aim of this study is to show and compare the actions of Simvastatin (Simv) and Erythropoietin (Epo) in renal expression of nuclear factor kappa B (NFκB), transforming growth factor-β (TGF-β), basic fibroblast growth factor (bFGF), platelet-derived growth factor B (PDGF-B), fibronectin and development of interstitial fibrosis in rats with unilateral ureteral obstruction (UUO). A total of 48 Sprague–Dawley rats were allocated to 4 groups of sham, Epo, Simv and control. Unilateral ureteral ligation was performed on all rats except the Sham group. For interstitial fibrosis Masson’s trichrome stain and for the expression of TGF-β, PDGF-B, bFGF, NFκB and fibronectin, immunohistochemical methods were used. In the Epo and Simv groups, expression of TGF-β and fibronectin and staining with Masson’s trichrome were less compared to the control group. In addition, fibronectin expression in the Epo group was less than the Simv group. Unlike the Simv group, NFκB and bFGF expression in the Epo group were less when compared to the control group. Consequently, it was seen that both Epo and Simv prevented fibrosis in ON. Epo was superior in this effect by suppressing the expressions of NFκB and bFGF more effectively than Simv. Based on this finding, Epo might be a better agent than Simv in the prevention of fibrosis in ON.     

梓醇对5/6肾切除大鼠肾组织TGF-β1、CTGF表达的影响

目的:观察梓醇(catalpol)对肾衰大鼠肾组织TGF-β1、CTGF表达的影响。方法:将Wistar大鼠50只随机分为正常组,模型组,梓醇高、中、低剂量(100、50、10 mg/kg)组。除正常组外,其余各组大鼠均行5/6(ablation/infarction,A/I)肾切除法建立肾衰竭大鼠模型,从手术当日开始,梓醇各剂量组连续灌胃给药60 d。检测血清肌酐(Cr)、尿素氮(BUN)、超敏反应蛋白(hs-CRP)、血红蛋白(Hb)水平变化,ELISA法检测肾纤维化指标肾皮质转化生长因子(TGF-β1)、结缔组织生长因子(CTGF)的水平变化,HE染色观察大鼠肾脏病理变化,免疫组化法检测肾组织TGF-β1、CTGF的表达。结果:模型组大鼠血清Cr、BUN、hs-CRP水平显著升高(P<0.01)、Hb水平明显降低(P<0.01);血TGF-β1、CTGF含量显著上升(P<0.01);肾组织TGF-β1、CTGF的表达量增多。比较模型组,梓醇高(P<0.01)、中(P<0.05)、低(P<0.05)剂量组大鼠血清Cr、BUN、hs-CRP、TGF-β1、CTGF水平降低,Hb水平升高,肾组织TGF-β1、CTGF的表达量减少,其中尤以梓醇高剂量组疗效最佳。结论:梓醇可有效阻断大鼠肾纤维化进程、改善微炎症反应,保护大鼠肾功能,其作用机制可能与通过下调TGF-β1、CTGF表达,抑制纤维细胞增殖,减少纤维组织增生、炎性浸润相关,且具剂量依赖性。     

Are there any new reliable markers to detect renal injury in obese children?

Aim: The aim of this study was to examine the serum and urine levels of kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), osteopontin (OPN), matrix metalloproteinase-9 (MMP-9), and serum Cystatin-C to determine the renal effect of obesity in obese children.

Methods: Seventy-two obese and 35 non-obese healthy children were included in this study. Blood pressure (BP) was evaluated with office measurement. Creatinine, cystatin C, lipids, fasting glucose, and insulin levels were measured, and homeostasis model assessment -insulin resistance (HOMA-IR) was calculated. The urine albumin/creatinine ratio was calculated. The serum and urine KIM-1, NGAL, OPN, and MMP-9 levels were measured.

Results: Serum cystatin-C, triglyceride, and homeostasis model assessment-insulin resistance (HOMA-IR) index were found to be significantly higher in the obese group (p?=?.0001), and high-density lipoprotein (HDL) cholesterol was found to be significantly lower (p?=?.019) in the obese group. No significant differences were found in serum KIM-1, NGAL, OPN or MMP-9 levels between groups (p?>?.05). No significant differences were found in urine KIM-1 and MMP-9 levels (p?>?.05), Urine NGAL, and OPN levels were found significantly higher in obese groups (p?Conclusions: According to our results, although serum KIM-1, NGAL, OPN, MMP-9, and urine MMP-9, urine KIM-1 do not appear to be ideal markers to evaluate renal injury in the early period of obesity, the serum levels of cystatin C and urine NGAL, urine OPN can be used as a good marker for assessing the renal effect of obesity which can lead end stage renal disease in pediatric population.     

Mechanism of miR-365 in regulating BDNF-TrkB signal axis of HFD/STZ induced diabetic nephropathy fibrosis and renal function

Purpose

Diabetic nephropathy (DN) is one of the most serious complications of diabetes that leads to decline of renal function. Although numerous studies have revealed that microRNAs (miRNAs) play essential roles in the progression of DN, whether miR-365 is involved remains elusive.

Methods

The successful construction of DN model was confirmed by ELSIA, hematoxylin–eosin (HE) and Masson staining assay. The expression of miR-365 was detected through RT-qPCR. The levels of BDNF, p-TrkB, α-smooth muscle actin (SMA), collagen IV (Col.IV), transforming growth factor-β1 (TGF-β1), tumor necrosis factor α (TNF-α), and interleukin-6 (IL-6) were evaluated by western blot, IF or ELISA assays. Luciferase reporter assay was used to detect the interaction between miR-365 and BDNF.

Results

The DN mice model was induced by streptozotocin (STZ). Then miR-365 expression was found to upregulate in tissues of DN rat. Furthermore, elevated expression of miR-365 was found in high glucose (HG)-treated HK-2 cells. Silencing of miR-365 suppressed the accumulation of ECM components and secretion of inflammatory cytokines in HK-2 cells. In addition, it was demonstrated that miR-365 could target BDNF. The protein levels of BDNF and p-TrkB were negatively regulated by miR-365 in HK-2 cells. Moreover, inhibition of miR-365 suppressed the levels of SMA, Col.IV, TGF-β1, TNF-α, and IL-6, indicating the renal fibrosis was inhibited by miR-365 knockdown.

Conclusion

MiR-365 could regulate BDNF-TrkB signal axis in STZ induced DN fibrosis and renal function. The results of the current study might provide a promising biomarker for the treatment of DN in the future.

     

转化生长因子β1短发夹RNA对白蛋白刺激人肾近曲小管上皮细胞细胞因子表达的影响

目的 研究pcDU6载体质粒介导的转化生长因子β1（TGF-β1）短发夹RNA（shRNA）对人血清白蛋白（HSA）致人肾近曲小管上皮细胞（HK2细胞）增殖，TGF-β1、结缔组织生长因子（CTGF）和纤连蛋白（FN）表达的影响，并探讨有关机制。方法 构建TGF-β1shRNA的pcDU6载体质粒，体外培养HK2细胞株。采用脂质体转染将表达TGF-β1shRNA的pcDU6质粒载体（pcDU6-A1-A2和peDU6-B1-B2）分别导人实验组细胞。用HSA（5g／L）刺激HK2细胞12h或24h。四甲基偶氮唑盐（MTF）比色法测定细胞增殖水平。RT-PCR半定量分析HK2细胞中TGF-β1、CTGF和FNmRNA的表达水平；双抗夹心酶联免疫吸附法检测HK2细胞培养液中TGF-β1及FN蛋白质水平。结果 HK2细胞在HSA刺激下，其TGF-β1、CTGF及FNmRNA的表达明显上调，培养液中TGF-β1和FN的蛋白质含量亦明显升高（P〈0．05）。与pcDU6空载体组比较，pcDU6载体质粒介导的TGF-β1shRNA干扰组TGF-β1、CTGF及FNmRNA的表达明显下调（P〈0．05）。TGF-β1shRNA转染HK2细胞后12h或24h，细胞培养液中TGF-β1和FN蛋白质含量明显下降，HK2细胞增殖被部分抑制（P〈0．05）。在细胞增殖、TGF-β1、CTGF及FN基因表达方面，TGF-β1shRNA干扰组组间比较，以及pcDU6空载体转染组与HSA刺激组比较，差异均无统计学意义。结论 peDU6载体质粒介导的TGF-β1shRNA能够明显抑制HSA刺激下HK2细胞增殖、TGF-β1、CTGF和FN基因的表达。HSA刺激HK2细胞增殖及CTGF和FN基因的过表达可能通过TGF-β1介导。     

Premature senescence and cellular phenotype transformation of mesangial cells induced by TGF-B1

Abstract

Background: Transforming growth factor-β1 (TGF-β1) is a polypeptide member of the transforming growth factor β superfamily of cytokines and performs many cellular functions. Its overexpression may lead to renal fibrosis. Aim: This study planed to investigate the effects of TGF-β1 on the cell cycle and phenotype of mesangial cells. Methods: Rat mesangial cells were cultured together with different concentrations (0, 1, 2, 5, and 10?ng/mL) of TGF-β1 for specified times from 0?min to 72?h. 0?ng/mL TGF-β1 and 0?min served as controls. Cell cycles were assessed by flow cytometry and α-smooth muscle actin expression (α-SMA) protein expression by western blot analysis. All data were presented as Mean?±?SD. Statistical analysis was performed by using one-way analysis of variance and correlation analysis. Results were considered significant at p?<?0.05. Results: After 15?min of co-culture with different concentrations of TGF-β1, the percentage of mesangial cells in G0/G1 phase was significantly elevated compared to the control (p?<?0.05). 12?h co-culture induced cell hyperplasia, 24?h co-culture obvious up-regulation of α-SMA (p?<?0.01) and one or two cells’ myofibroblast phenotype transition, and 36?h co-culture several cells’ phenotype transition. Correlation analysis prompted that the TGF-β1-induced premature aging was time-dependent (p?<?0.01). Conclusion: TGF-β1 may induce mesangial cells’ premature senescence and myofibroblast-like phenotype transformation time-dependently, which may contribute to the development of early stage of glomerulosclerosis.     

Protective effects of estrogen and bortezomib in kidney tissue of post-menopausal rats: an ultrastructural study

Purpose: Symptoms and disorders related to menopause and its associated estrogen deficiency have become a considerable health concern worldwide. Ovarian hormone depletion/estrogen deficiency can be usefully studied using animal models after removal of the ovaries [ovariectomy (Ovx)]. This study assessed renal changes after Ovx-induced estrogen deficiency in a rat model.

Methods: Rats were randomly allotted into one control group (group I, healthy) and three study groups (group II, Ovx group; group III, Ovx +17β-estradiol group; and group IV, Ovx?+?bortezomib group).

Results: In the Ovx group (group II), thickening of glomerular capillary walls, narrowing of Bowman’s capsular space, glomerular hypertrophy, atrophic tubules, and loss of the basal membranes of the tubules were observed. Mesangial cell proliferation was observed, particularly in the glomerulus. Immunohistochemical (IHC) staining studies in this group showed dense staining in the mesangial cells, tubular cell Nf-KB/p65, and caspase-3. Groups III and IV (Ovx +17β-estradiol and Ovx?+?bortezomib) showed decreased NF-kB/p65 and caspase-3 expression compared with the Ovx group (p?Conclusion: In renal failure related to estrogen deficiency caused by Ovx, 17β-estradiol and bortezomib have a protective effect on renal tissue.     

Prolonged alendronate treatment prevents the decline in serum TGF-β1 levels and reduces cortical bone strength in long-term estrogen deficiency rat model

IntroductionWhile the anti-resorptive effects of the bisphosphonates (BPs) are well documented, many questions remain about their mechanisms of action, particularly following long-term use. This study evaluated the effects of alendronate (Ale) treatment on TGF-β1 signaling in mesenchymal stem cells (MSCs) and osteocytes, and the relationship between prolonged alendronate treatment on systemic TGF-β1 levels and bone strength.MethodsTGF-β1 expression and signaling were evaluated in MSCs and osteocytic MLO-Y4 cells following Ale treatment. Serum total TGF-β1 levels, a bone resorption marker (DPD/Cr), three-dimensional microCT scans and biomechanical tests from both the trabecular and cortical bone were measured in ovariectomized rats that either received continuous Ale treatment for 360 days or Ale treatment for 120 days followed by 240 days of vehicle. Linear regression tests were performed to determine the association of serum total TGF-β1 levels and both the trabecular (vertebrae) and cortical (tibiae) bone strength.ResultsAle increased TGF-β1 signaling in the MSCs but not in the MLO-Y4 cells. Ale treatment increased serum TGF-β1 levels and the numbers of TGF-β1-positive osteocytes and periosteal cells in cortical bone. Serum TGF-β1 levels were not associated with vertebral maximum load and strength but was negatively associated with cortical bone maximum load and ultimate strength.ConclusionsThe increase of serum TGF-β1 levels during acute phase of estrogen deficiency is likely due to increased osteoclast-mediated release of matrix-derived latent TGF-β1. Long-term estrogen-deficiency generally results in a decline in serum TGF-β1 levels that are maintained by Ale treatment. Measuring serum total TGF-β1 levels may help to determine cortical bone quality following alendronate treatment.     

Urinary Transforming Growth Factor-β1 Excretion in Renal Allograft Recipients During the Early Post-transplantation Period

Background.?Transforming growth factor-β₁ (TGF-β₁), the major fibrogenic growth factor, is implicated in the pathogenesis of renal scarring in experimental and clinical nephropathies as well as in chronic allograft nephropathy. In this study we examined the pattern of changes of TGF-β₁ excretion in the urine and the sites of TGF-β₁ expression in the kidney of transplanted patients during the early post-transplantation period. Methods.?Eighteen renal allograft recipients were included in the study. In all patients urinary TGF-β₁ levels were determined by ELISA in sequential measurements during the first two postoperative months and compared to that of 14 healthy subjects. The renal expression of TGF-β₁ protein was studied in 4 patients that underwent a biopsy of the transplanted kidney at the same period. All patients were treated with prednisolone, cyclosporin, and mycophenolate mofetil. Results.?Urinary TGF-β₁ levels were increased during the first postoperative days. Although they were gradually reduced during the first two post-operative months, they remained significantly higher compared to those of normal subjects (580 ± 148 ng/24 h vs. 310 ± 140 ng/24 h p<0.01). The decline of urinary TGF-β₁ excretion followed that of serum creatinine. TGF-β₁ protein expression was identified within the cytoplasm of tubular epithelial cells of transplanted patients. Conclusions.?Elevated urinary TGF-β₁ levels are observed during the early post-transplantation period in renal allograft recipients and are maintained high even after restoration of renal function to normal.