肝细胞生长因子及其受体在常染色体显性多囊肾病囊肿衬里上皮细胞的表达研究

目的 研究常染色体显性多囊肾病(ADPKD)囊肿衬里上皮细胞中肝细胞生长因子(HGF)及其受体c-MET的分布。方法 采用酶联免疫(ELISA)法测定ADPKD患者囊肿液、血清和原代培养ADPKD囊肿衬里上皮细胞上清液中HGF浓度。逆转录聚合酶链反应(RT-PCR)、原位杂交、Western印迹、免疫组织化学及计算机图像定量分析 HGF、c-MET mRNA和蛋白在囊肿衬里上皮细胞的表达。结果 ADPKD未透析患者囊液中HGF浓度为(8.61±0.07)ng/ml,显著高于血清HGF浓度(0.26±0.05)ng/ml(P<0.01)。原代培养的囊肿衬里上皮细胞上清液中也检测到HGF,浓度为(1.43±0.01)ng/ml。体外培养的ADPKD囊肿衬里上皮细胞中c-MET mRNA含量(75.69±12.36)与HGF mRNA含量(79.89±11.58)呈正相关(r=0.54,P<0.01)。ADPKD囊肿组织中囊肿衬里上皮细胞c-MET mRNA含量(114.75±36.24)与HGF mRNA含量(136.48±39.69)呈正相关(r=0.50,P<0.01)。ADPKD囊肿组织中囊肿衬里上皮细胞c-MET蛋白含量(101.68±21.06)与HGF蛋白含量(125.03±19.34)、培养的囊肿衬里上皮细胞c-MET蛋白含量(11.60±1.83)与HGF蛋白含量(18.46±1.71)均呈正相关(r=0.51,P<0.05;r=0.67,P<0.01)。结论 ADPKD囊肿衬里上皮细胞可合成和分泌HGF。HGF可调节囊肿衬里上皮细胞表达c-MET。     

Cyst formation and growth in autosomal dominant polycystic kidney disease

Previous morphologic studies on kidneys from adult patients with autosomal dominant polycystic kidney disease (ADPKD) indicates that the cysts developed from nephrons and collecting ducts in association with hyperplasia of epithelial cells lining the cyst walls. In the present study, we systematically evaluated by scanning electron microscopy 387 cysts in polycystic kidneys obtained from 10 adult patients. Some cysts were lined by cells typical of collecting duct (7.2%), proximal tubule (1.8%) or glomerular visceral (2.1%) epithelium. The remaining cysts were lined by a single layer of phenotypically undefined (84.0%) or markedly hyperplastic (4.9%) epithelium. The median plane surface area of individual cells within cysts was 182 X 10(-8) cm2. Among all cysts the surface area of single epithelial cells ranged between 22 and 2530 X 10(-8) cm2, but within single cysts the range of individual cell surface areas was more narrow. Mean cell surface area did not increase in direct proportion to cyst diameter; thus, epithelial hyperplasia is a central element in the progressive enlargement of cysts. In some cysts hyperplasia was accentuated by projections into cyst lumens of polyps, small adenomas and cord-like arrangements of cells. Epithelial polyps were found in the cysts of one non-azotemic patient, excluding renal failure as a cause of this accentuated type of epithelial proliferation. Morphologic evidence that cysts compressed adjacent renal parenchyma was observed in all kidneys. In 11 cysts bisected and then both halves thoroughly examined by scanning electron microscopy, one or two tubule openings were seen in one of the hemisections in three cysts (27.3%).(ABSTRACT TRUNCATED AT 250 WORDS)     

Angiogenesis and autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by the growth of multiple cysts that in many cases result in end-stage renal disease. Current strategies to reduce cyst progression in ADPKD focus on modulating cell turnover, fluid secretion, and vasopressin signalling; but an alternative approach may be to target pathways providing “general support” for cyst growth, such as surrounding blood vessels. This could be achieved by altering the expression of growth factors involved in vascular network formation, such as the vascular endothelial growth factor (VEGF) and angiopoietin families. We highlight the evidence that blood vessels and vascular growth factors play a role in ADPKD progression. Recent experiments manipulating VEGF in ADPKD are described, and we discuss how alternative strategies to manipulate angiogenesis may be used in the future as a novel treatment for ADPKD.     

Aberrant epithelial cell growth in autosomal dominant polycystic kidney disease

Renal cyst enlargement in autosomal dominant polycystic kidney disease (ADPKD) is characterized by increased epithelial cell proliferation and fluid accumulation. Using monolayer epithelial cultures derived from individually microdissected human ADPKD cysts and immunolocalization studies in vivo, the roles of matrix and growth factors in aberrant ADPKD cell proliferation have been studied. Abnormal ADPKD basement membrane ultrastructure was associated with increased turnover of 35S-labeled heparan sulfate proteoglycans (HSPG) by comparison to normal renal tubule epithelia in vitro. Mitogenic assays demonstrated significant increase in 3H-thymidine incorporation into ADPKD epithelia grown on type I and type IV collagen by comparison to normal proximal straight tubules (PST), collecting ducts, and thick ascending limbs of Henle (TAL). Proliferation on laminin or fibronectin matrices was unchanged and immunolocalization of matrix proteins was polarized and restricted to basal membranes of both ADPKD cysts and renal tubule epithelia in vivo. ADPKD epithelia in vitro were hypersensitive to the mitogenic action of epidermal growth factor (EGF) and EGF immunoreactivity was detected in ADPKD cyst lining epithelia, in cyst fluid, and in conditioned media from confluent ADPKD cultures, suggesting an autocrine mechanism of growth regulation. In addition, inhibition of epithelial proliferation by transforming growth factor-beta (TGF-beta), which was 100% in normal renal tubule epithelia, was reduced to 41% in ADPKD epithelia.     

Boy with autosomal recessive polycystic kidney and autosomal dominant polycystic liver disease

BACKGROUND: Autosomal recessive polycystic kidney disease (ARPKD) shows a great phenotypic variability between patients, ranging from perinatal demise to mildly affected adults. Autosomal dominant polycystic liver disease (PCLD) does not manifest in childhood. CASE-DIAGNOSIS/TREATMENT: A boy was reported with the co-occurrence of ARPKD and PCLD. He presented at the age of 16 days with pyelonephritis and urosepsis. Subsequent investigations showed enlarged kidneys and hyperechogenic renal medulla and liver parenchyma. Genetic analysis revealed compound heterozygous mutations in the PKHD1 gene (p.Arg496X and p.Ser1862Leu). After his mother was diagnosed with PCLD, the finding of a liver cyst on ultrasound prompted analysis of the PRKCSH gene, revealing a missense mutation (p.Arg139His). At the most recent follow-up at 13 years of age, the patient's course and clinical examination was uneventful with normal renal and liver function without evidence of portal hypertension. CONCLUSIONS: The patient with ARPKD and PCLD has so far demonstrated a benign clinical outcome, consistent with the great phenotypic variability of ARPKD and, apart from the liver cyst, asymptomatic manifestation of PCLD in childhood. However, close long-term follow-up is mandatory.     

Hypertension in autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD) has been shown to be associated with a greater than 50 percent incidence of hypertension prior to deterioration in renal function as assessed by glomerular filtration rate. The present study provides evidence for increased cardiac pre-load, as assessed by plasma atrial natriuretic factor (ANF) and cardiac index, in hypertensive as compared to normotensive ADPKD. The hypertensive ADPKD patients exhibited an increased renal vascular resistance as compared to the normotensive patients in spite of comparable glomerular filtration rates. It is hypothesized that the renal involvement of hypertensive ADPKD patients causes an impaired renal response to the observed increase in cardiac index, and also may release a venoconstrictor (such as angiotensin) which contributes to the enhanced cardiac pre-load and thus the hypertension.     

Androgen receptor pathway in rats with autosomal dominant polycystic kidney disease

Androgens have been implicated in mediating disease escalation in autosomal dominant polycystic kidney disease (ADPKD). Dihydrotestosterone (DHT), an agonist, and flutamide (FLT), an antagonist, were administered to Han:SPRD rats with ADPKD, and the role of androgen receptor (AR) abundance and activation on the enlargement and function of cystic kidneys was evaluated. Renal AR abundance determined by immunoblots in 8- to 10-wk-old Cy/+ male rats was naturally increased four-fold above that of littermate +/+ controls. In male Cy/+, castration decreased AR abundance below control +/+ by -89.4%, and AR expression within cyst mural epithelial cells was strikingly decreased. Castration of Cy/+ male rats also reduced the usual increases in kidney weight by -49.7%, kidney cyst area by -34.0%, and serum urea nitrogen by -72.8%; these indices were restored to precastration levels by DHT. In Cy/+ male rats, FLT administration reduced the increase in kidney weight by -27.6% and serum urea nitrogen by -53.7% and decreased the increment in AR expression by -84.2% in comparison with untreated +/+ controls. There was no effect of FLT in female rats. Immunoblot expression of phospho-extracellular signal-regulated kinase 1/2 (P-ERK) and B-Raf, key intermediates in the mitogen-activated protein kinase pathway that are abnormally elevated in Cy/+, was unaffected by castration and/or administration of DHT or FLT. AR was not expressed in renal epithelial cell nuclei of androgen-deficient rats but was displayed in most tubule and mural cyst cell nuclei of androgen-replete rats. In androgen-deficient Cy/+, 80.6% of renal epithelial cells that had entered the cell cycle (proliferating cell nuclear antigen positive) also expressed P-ERK. In androgen-replete rats, proliferating cell nuclear antigen-positive cells co-expressed AR (12.7%), P-ERK (36.4%), and P-ERK + AR (45.0%); 5.9% were probably stimulated by other mitogenic mechanisms. It is concluded that androgens potentiate renal cell proliferation and cyst enlargement through ERK1/2-dependent and ERK1/2-independent signaling mechanisms in Han:SPRD. It is suggested that the basal rate of cell proliferation is determined by ERK1/2 signaling to a major extent and that androgens have additive effects.     

Role of keratinocyte growth factor in the pathogenesis of autosomal dominant polycystic kidney disease.

BACKGROUND: Previous studies have shown that the expression and distribution of keratinocyte growth factor (KGF), also known as FGF-7 (fibroblast growth factor-7) or HBGF-7 (heparin-binding growth factor-7), may be implicated in kidney cyst formation and expansion. However, there are no data on KGF expression in human autosomal dominant polycystic kidney disease (ADPKD) tissue, and it is unknown whether it affects ADPKD cyst-lining epithelial cell epithelial cell proliferation. METHODS: The expression and distribution of KGF and KGF receptor (KGFR) mRNA in ADPKD cystic and normal kidney tissues were examined using quantitative real-time polymerase chain reaction (PCR) and in situ hybridization. KGF and KGFR protein expression in the above tissues was analysed by immunohistochemistry and western blot. The effect of KGF on cyst-lining epithelial cell proliferation was assessed by MTT assay, and its effect on the cyst-lining epithelial cell cycle was analysed by flow cytometry. The effect of KGF on cyclin D1 and P21(wafl) gene expression in cyst-lining epithelial cells was also determined. RESULTS: KGF and KGFR mRNA expression in ADPKD cysts was higher than in normal kidney tissues. KGF and KGFR protein expression was also higher in ADPKD cysts and was localized to cyst-lining epithelial cells, tubular and interstitial cells. In vitro experiments revealed that KGF promoted cyst-lining epithelial cell proliferation, and decreased the ratio of G0/G1 phase but increased that of S phase. In response to KGF, the expression of the cyclin D1 gene in cyst-lining epithelial cells increased markedly while P21(wafl) expression decreased. CONCLUSIONS: KGF and KGFR expression was upregulated in ADPKD kidney tissues. KGF stimulated the proliferation of cyst-lining epithelial cell in vitro by regulating the expression of cyclin D1 and P21(wafl) genes. KGF may play a role in pathogenesis of ADPKD.     

Renal disease progression in autosomal dominant polycystic kidney disease

Background

Autosomal dominant polycystic kidney disease is a lifelong progressive disorder. However, how age, blood pressure, and stage of chronic kidney disease (CKD) affect the rate of kidney function deterioration is not clearly understood.

Methods

In this long-term observational case study up to 13.9?years (median observation period for slope was 3.3?years), serum creatinine was serially measured in 255 mostly adult patients. The glomerular filtration rate was estimated (eGFR) using a modified Modification of Diet in Renal Disease Study method. The total kidney volume (TKV) has been measured in 86 patients at one center since 2006.

Results

As age increased, eGFR declined significantly (P?Conclusion The declining rate of eGFR was relatively constant and did not correlate with age or eGFR after adolescence. eGFR was already low in young adult patients with hypertension. As age increased after adolescence, eGFR declined and TKV increased similarly between normal and high blood pressure groups. eGFR starts to decline in patients with normal eGFR, suggesting that the decline starts earlier than previously thought.     

Myofibroblast depletion reduces kidney cyst growth and fibrosis in autosomal dominant polycystic kidney disease

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Mineral bone disease in autosomal dominant polycystic kidney disease

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Therapeutic interventions for autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD) is the most common life-threatening hereditary disease in the United States and causes end-stage renal failure requiring dialysis and renal transplantation. There is no effective treatment for ADPKD in humans. However, there are now multiple clinical trials testing a host of therapeutic interventions in children and adults with ADPKD. The major therapeutic interventions being tested in patients with ADPKD include Tolvaptan, Octreotide, Sirolimus, Everolimus, and statins, angiotensin converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs).     

Laparoscopic nephrectomy for autosomal dominant polycystic kidney disease

Background The authors reviewed their experience with laparoscopic nephrectomy for autosomal dominant polycystic kidney disease to evaluate whether patient-related or surgery-related factors influence operative outcomes.Methods A retrospective review was carried out of 22 consecutive laparoscopic nephrectomies performed by one surgeon in a university setting between March 1998 and March 2003. The impact of patient factors (body mass index, preoperative hemoglobin level, preoperative blood urea nitrogen and creatinine, kidney size and side, prior abdominal surgery, dialysis) and surgical factors (surgeon experience and preoperative embolization) on short-term outcomes (estimated blood loss, transfusion requirements, operative time, conversion, intra- and postoperative complications and length of stay) was analyzed using the Students t-test, Pearson correlation, and Mann–Whitney and Fisher tests.Results A total of 19 patients underwent 22 nephrectomies. The average patient age was 49 years (range, 36–65 years) and the average body mass index was 31.4 kg/m² (range, 20.4–64.5 kg/m²). Fourteen patients (68%) were receiving dialysis. Fifteen right (68%) and 7 left (32%) nephrectomies were performed. The median kidney size was 22 cm (range, 8–50 cm). Five patients (23%) had preoperative embolization. The median operative time was 255 min (range, 95–415 min). There were no mortalities. The intraoperative complication rate was 18% (1 vena cava laceration, 1 cecal perforation, 1 dialysis fistula thrombosis, 1 intrarenal bleeding requiring conversion), and the postoperative complication rate was 32% (1 myocardial infarction, 1 urgent laparotomy for clinical peritonitis, 1 minor bile fistula, 1 AV fistula thrombosis, 2 incisional hernias, 1 urinary retention). Four procedures (18%) were converted (1 for vena cava laceration, 1 for cecal perforation, 1 for intrarenal bleeding, 1 for adhesions). The median blood loss was 400 ml (range, 100–5000 ml). Eight patients (36%) received transfusions (median, 2 units). The median length of stay was 4 days. The patients who required blood transfusions had lower preoperative hemoglobin levels. Preoperative embolization did not affect surgical outcome. However, surgeon experience significantly reduced operative time.Conclusions Laparoscopic nephrectomy for autosomal dominant polycystic kidney disease is a safe procedure, providing patients with a short hospital stay. Complication and conversion rates are relatively high.Presented at the 11th International Congress of the European Association for Endoscopic Surgery and other Interventional Techniques (EAES), Glasgow, 15–18 June 2003     

Genotype-phenotype correlations in autosomal dominant and autosomal recessive polycystic kidney disease

The phenotypes that are associated with the common forms of polycystic kidney disease (PKD)--autosomal dominant (ADPKD) and autosomal recessive (ARPKD)--are highly variable in penetrance. This is in terms of severity of renal disease, which can range from neonatal death to adequate function into old age, characteristics of the liver disease, and other extrarenal manifestations in ADPKD. Influences of the germline mutation are at the genic and allelic levels, but intrafamilial variability indicates that genetic background and environmental factors are also key. In ADPKD, the gene involved, PKD1 or PKD2, is a major factor, with ESRD occurring 20 yr later in PKD2. Mutation position may also be significant, especially in terms of the likelihood of vascular events, with 5' mutations most detrimental. Variance component analysis in ADPKD populations indicates that genetic modifiers are important, but few such factors (beyond co-inheritance of a TSC2 mutation) have been identified. Hormonal influences, especially associated with more severe liver disease in female individuals, indicate a role for nongenetic factors. In ARPKD, the combination of mutations is critical to the phenotypic outcome. Patients with two truncating mutations have a lethal phenotype, whereas the presence of at least one missense change can be compatible with life, indicating that many missense changes are hypomorphic alleles that generate partially functional protein. Clues from animal models and other forms of PKD highlight potential modifiers. The information that is now available on both genes is of considerable prognostic value with the prospects from the ongoing genetic revolution that additional risk factors will be revealed.     

Prenatal onset of autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease presenting in the fetus or newborn is rare, only 22 cases having been reported in the literature. A case is reported of a premature newborn infant with severe renal involvement and extrarenal associated abnormalities. The literature is reviewed, and the importance of considering this entity in infants with polycystic kidney disease is discussed since it may affect both genetic counseling and surgical management when radiographically detected.     

Renal infections in autosomal dominant polycystic kidney disease

Renal infection is a common occurrence in autosomal dominant polycystic kidney disease (ADPKD) and often leads to serious complications, including perinephric abscess, septicemia, and death. Important predisposing factors include age, female sex, and recent instrumentation of the urinary tract. Renal infections in ADPKD are most commonly caused by gram-negative enteric organisms. Diagnosis of these infections may be difficult since some patients do not have bacteriuria. Eradication of cyst infections with conventional antibiotic therapy can be difficult despite in vitro sensitivity of responsible organisms to the agents administered. We review recent studies of the anatomic and functional characteristics of renal cysts and discuss their possible relevance to the treatment of renal cyst infections. Finally, we set forth guidelines for the use of diagnostic studies, antimicrobial therapy, and surgical intervention for polycystic kidney infections.     

常染色体显性遗传性多囊肾病患者与血管紧张素转换酶基因多态性的关系

目的 研究人常染色体显性遗传性多囊肾病（ADPKD）与血管紧张素转换酶（ACE）基因多态性的关系。 方法 用PCR方法对103例ADPKD患者及16个ADPKD家系（患者35例,非患病直系亲属30人）进行ACE基因多态性分析。收集患者及家系成员的临床资料,以发病年龄、肝囊肿、高血压、尿路感染、尿路结石、血尿等为主要参数,用统计学方法研究该病ACE基因多态性与ADPKD的关系。 结果 DD型患者的发病年龄比DI型患者早7.2岁[（31.90±11.41）岁比（39.10±10.08）岁];DD型患者的发病年龄比Ⅱ型患者[（46.15±14.74）岁]早14.25岁;DI型患者的发病年龄比Ⅱ型患者早7.05岁,各型间的差异均有统计学意义（均P ＜ 0.05）。3组间高血压、血尿差异有统计学意义。11个家系检查结果显示,ACE基因多态性在ADPKD家系中具有遗传连锁关系,但无统计学意义;家系中患病与非患病者ACE基因型频率差异无统计学意义;家系中患病与非患病者男女之间ACE基因型频率差异无统计学意义;家系中肾功能不全组与肾功能正常组之间DD型及D等位基因频率差异有统计学意义（P ＜ 0.05）。 结论 DD型患者的发病年龄较早,Ⅱ型患者的发病年龄较晚,DI型居中。DI型患者血尿的发生率较高,Ⅱ型患者血尿的发生率较低。DI型患者高血压的发生率较高。ACE基因多态性在ADPKD家系中不提供基因诊断信息; ACE基因多态性与人ADPKD的发病无显著相关性;ACE基因多态性与性别无明显关系。DD型基因型是ADPKD发生肾功能不全的易感因素。