Pyridoxal Phosphate and Hepatocyte Growth Factor Prevent Dialysate-Induced Peritoneal Damage
Sakurako Nakamura and
Toshimitsu Niwa
Department of Clinical Preventive Medicine, Nagoya University Hospital, Nagoya, Japan
Address correspondence to: Dr. Toshimitsu Niwa, Department of Clinical Preventive Medicine, Nagoya University Hospital, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8560, Japan. Phone: +81-52-744-1980; Fax: +81-52-744-1954; E-mail: tniwa{at}med.nagoya-u.ac.jp
Glucose-based peritoneal dialysate (PD) is responsible for increasedaccumulation of advanced glycation end products (AGE) in theperitoneum of continuous ambulatory peritoneal dialysis patients.Pyridoxal 5'-phosphate (PLP), a derivative of vitamin B6, protectsproteins from glycation. Hepatocyte growth factor (HGF) healsdamaged tissues in a reciprocal manner against TGF-1. First,with the use of gas chromatography-mass spectrometry, whetherPLP traps 3-deoxyglucosone (3DG), a major glucose degradationproduct in PD, was determined. Then, whether rat peritonealtissue damages induced by intraperitoneal administration ofglucose-based PD is ameliorated by PLP or HGF was examined.In vitro incubation with PLP markedly decreased concentrationof 3DG in a dose-dependent manner, demonstrating the 3DG-trappingeffect of PLP. The peritoneum of PD-treated rats was significantlythickened compared with that of physiologic saline-treated rats.Both PLP and HGF prevented the thickening of rat peritoneuminduced by PD and ameliorated accumulation of AGE and expressionof TGF-1, vascular endothelial growth factor, and type 1 collagenand a number of blood vessels. Furthermore, expression of HGFwas significantly increased in the peritoneum of PLP-treatedrats compared with that of PD-treated rats. In conclusion, PLPshows 3DG-trapping effect. PLP and HGF prevented peritonealthickening; accumulation of AGE; expression of TGF-1, vascularendothelial growth factor, and type 1 collagen; and neoangiogenesisin rat peritoneum induced by PD.
Long-term peritoneal dialysis contributes to functional andstructural deterioration of peritoneal membrane. Glucose-basedperitoneal dialysate (PD) contains high levels of glucose degradationproducts (GDP) formed during heat-sterilization procedure, andthese GDP may readily react with proteins and accelerate accumulationof advanced glycation end products (AGE) (1,2). Accumulationof AGE is associated with peritoneal dysfunction in continuousambulatory peritoneal dialysis (CAPD) patients (3,4). Thus,the prevention of AGE accumulation in the peritoneum is necessaryfor maintenance of long-term CAPD.
New PD solutions with reduced contents of GDP—for example,amino acid-based PD (5), filter-sterilized fluids (6), and two-chamberedPD—have been developed to keep glucose separated frombuffer before use (7). These PD solutions are expected to reducetissue damage and accumulation of AGE in the peritoneum. However,alternative strategies, such as administration of AGE inhibitorsor the agents that promote tissue repair, should also be developed.Some AGE inhibitors exert beneficial effects on diabetic complicationsin animal models (8) mainly by trapping reactive dicarbonylsthat are produced during persistent hyperglycemia (9). However,such inhibitors could be toxic for living tissues because theyalso trap vitamin B6 and neuron-transmitting substances, resultingin vitamin B6 deficiency symptoms such as seizure attacks. Therefore,safe drugs should be developed for the treatment of AGE-relateddisease.
Recently, pyridoxamine (PM), a vitamin B6 derivative, was demonstratedto inhibit formation of AGE, especially by blocking postamadoriprocesses (10), and to inhibit the development of diabetic complicationsand vascular disease in animal models (11,12). Its dicarbonyls-trappingeffect also accounts for inhibition of AGE formation (13). Pyridoxal5'-phosphate (PLP) is another derivative of vitamin B6, whichprotects proteins from glycation (14–16), although itsmechanism is not yet elucidated.
Hepatocyte growth factor (HGF) heals damaged organ in a reciprocalmanner against TGF-1 (17). We previously demonstrated that increasedexpression of HGF was focally detected in the peritoneal tissuesof CAPD patients with low ultrafiltration capacity comparedwith those with normal ultrafiltration capacity (18).
In this study, we determined whether PLP traps 3DG, because3DG is a major GDP in PD formed during heat sterilization (19)and is a precursor of AGE such as imidazolone (20). Furthermore,we examined whether intraperitoneal administration of PLP andHGF shows beneficial effects on PD-induced peritoneal damage,by assessing morphologic changes, the accumulation of AGE, andexpression of growth factors in the peritoneum.
In Vitro Sample Preparation and 3DG Measurement
To determine whether PLP traps GDP, we incubated 3DG (molecularweight 162.1; Dojindo Laboratories, Kumamoto, Japan) with PLP(molecular weight 247.1; Sigma-Aldrich, St. Louis, MO) in vitro.In brief, 3DG (30.8 µM) in 0.1 M phosphate buffer wasincubated with PLP at concentrations of 5, 15, and 30 mM at37°C for 24 h. 3DG solution without PLP was kept immediatelyat –30°C until measurement. For comparing the 3DG-trappingability of PLP with the other vitamin B6 derivatives, pyridoxal(PL) hydrochloride (molecular weight 203.6; Sigma-Aldrich) andPM dihydrochloride (molecular weight 241.1; Sigma-Aldrich) atthe same concentrations as PLP were incubated with 3DG solution.After 24 h of incubation at 37°C, all samples were keptimmediately at –30°C. 3DG concentration was measuredby gas chromatography-mass spectrometry, according to the methodpreviously described (21).
Experimental Design
Sprague-Dawley rats (7 wk old, male, 240 to 250 g) were allowedfree access to food and water and were divided into four groups(seven rats per group): (1) physiologic saline (PS) group given20 ml of PS, (2) PD group given 20 ml of PD (Dianeal PD-2, 2.5%glucose; Baxter Healthcare Corp., Round Lake, IL), (3) PLP groupgiven 20 ml of PD that contained 50 mg of PLP (10.1 mM), and(4) HGF group given 20 ml of PD that contained 1 µg ofHGF (Pepro Tech EC Ltd., London, UK). The concentration of 3DGin unused PD was 0.26 mM. All solutions were administered intraperitoneallyto the rats once a day for 28 d. A rat that was treated withHGF was excluded from the study because it died of unknown causeon the 25th day after starting the experiment. Then, all ofthese rats were anesthetized and their visceral peritoneum includingcolons and parietal peritoneum along with muscles were excised.Tissues were cut into pieces and kept in phosphate-bufferedformaldehyde solutions for 3 d. After fixation, these peritonealtissues were embedded in paraffin, and thin sections (3 to 4µm) were obtained for periodic acid-Schiff staining andimmunohistochemical staining for AGE, growth factors, and extracellularmatrix protein. The experimental protocol was approved by theAnimal Care Committee of Nagoya University Hospital.
Immunohistochemical Study
After paraffin was removed from cut sections, they were treatedwith boiled citrate buffer (10 mM, pH 6.0) for 10 min beforethe staining of AGE, blood vessels, and type I collagen. Regardinggrowth factors, the sections were treated by diluted proteinaseK solution (0.01 mg/ml) for 10 min before staining. An avidin-biotincoupling technique was applied to all cases of immunostaining.For detecting AGE in the peritoneum, a monoclonal anti-imidazoloneantibody (1:100) and a monoclonal anti-N-(carboxymethyl) lysine(CML) antibody (1:200) were prepared. These two anti-AGE antibodieswere produced at our laboratory, and their epitopes and reactivitywere characterized (20,22). For determining the expression ofTGF-1, HGF, and vascular endothelial growth factor (VEGF), apolyclonal anti-TGF-1 antibody, a polyclonal anti-HGF antibody,and a monoclonal anti-VEGF antibody (1:20; Santa Cruz Biotechnology,Santa Cruz, CA) were used, respectively. For clarifying thelocation of blood vessels, a polyclonal anti-von Willebrandfactor antibody (1:200; DAKO, Glostrup, Denmark) was used. Localizationof type I collagen in the peritoneum was detected using a polyclonalanti-rat collagen I antibody (1:20; Sanbio bv, Am Uden, Netherlands).
Histologic Analysis
To assess histologic alterations and to quantify accumulationof AGE and expression of growth factors and type I collagenin the peritoneum, we used colon segments surrounded by thevisceral peritoneum. We measured thickness of these visceralperitonea including outer muscle layers. In brief, we put lightmicroscopic pictures of the peritoneum taken on 10 differentlocations per section into a computer memory board using a digitalcamera (DN100; Nikon, Tokyo, Japan) and measured the thicknessof the outer layer in each picture in a blind manner using NIHImage 1.62. The average value of 10 measurements was adoptedas representative of the case. To evaluate the accumulationof AGE and expression of growth factors in the visceral peritoneum,we took immunostaining pictures of imidazolone, CML, TGF-1,HGF, VEGF, and type I collagen at 10 different locations andrandomly measured their positive areas per 1-mm length of thevisceral peritoneum including outer muscle layer using the NIHImage 1.62. We counted the number of blood vessels per 1-mmlength of the peritoneum at 10 different locations, and theaverage number of them was adopted as a representative value.When there were no significant differences among the four groupsusing the visceral peritoneum, similar measurement was performedusing the parietal peritoneum. When using the parietal peritoneum,positive area and the number of blood vessels were measuredup to the depth of 300 µm from the peritoneal surface.
Statistical Analyses
Results are expressed as mean ± SD. One-way ANOVA wasperformed to determine whether parameters differed among thefour groups. When there were significant differences by ANOVA,Fisher protected least significant difference test was usedfor further analysis between groups. P < 0.05 was consideredsignificant.
3DG-Trapping Effect of PLP
3DG-trapping effect was determined after a 24-h incubation of3DG with PLP, PL, or PM. The concentration of 3DG was decreasedin samples that were incubated with PLP (Figure 1). PLP decreased3DG levels to 52.2% at 5 mM, 23.7% at 15 mM, and 14.0% at 30mM, respectively. PL did not decrease 3DG levels as follows:100% at 5 mM, 96.4% at 15 mM, and 94% at 30 mM, respectively(Figure 1). PM hardly decreased 3DG levels to 93.1% at 5 mM,89.7% at 15 mM, and 89.6% at 30 mM, respectively (Figure 1).Thus, only PLP exerted 3DG-trapping effect.
Figure 1. 3-Deoxyglucosone (3DG)-trapping effect of pyridoxal 5'-phosphate (PLP), pyridoxal (PL), and pyridoxamine (PM) after incubation at 37°C for 24 h. Data are representative of three independent experiments and are shown as mean ± SD. , PLP; , PL; , PM; *P < 0.05, ** P < 0.01, P *** < 0.001 compared with 0 mM
Effects of PLP and HGF on Peritoneal Damage Induced by PD
The visceral peritoneal layer was significantly thickened inthe PD group as compared with the PS group. Administration ofPLP and HGF inhibited peritoneal thickening induced by PD (Table 1,Figure 2). AGE such as imidazolone and CML were accumulatedin the visceral peritoneum of the PD group, whereas only a smallpositive area was noted in the PS group (Table 1, Figure 3,A, B, E, and F). Administration of PLP significantly attenuatedaccumulation of imidazolone and CML in the visceral peritoneum(Table 1, Figure 3, C and G). Administration of HGF also attenuatedaccumulation of AGE in the peritoneum, although not so remarkablyas PLP (Table 1, Figure 3, D and H). Intraperitoneal administrationof PD increased the positive area of type I collagen in thevisceral peritoneum as compared with the PS group (Table 1,Figure 3, I and J). Administration of PLP and HGF significantlydecreased the positive area of type I collagen in the peritoneumas compared with the PD group (Table 1, Figure 3, K and L).
Figure 2. Light microscopic pictures of periodic acid-Schiff staining of the visceral peritoneum. (A) The peritoneum of a rat that was treated with physiologic saline (PS). (B) The peritoneum of a rat that was treated with peritoneal dialysate (PD). (C) The peritoneum of a rat that was treated with PD that contained PLP. (D) The peritoneum of a rat that was treated with PD that contained hepatocyte growth factor (HGF). Magnification, x50.
Figure 3. Light microscopic pictures of imidazolone, N-(carboxymethyl)lysine (CML), and type 1 collagen accumulation in the visceral peritoneum. (A) Imidazolone in the peritoneum of a rat that was treated with PS. (B) Imidazolone in the peritoneum of a rat that was treated with PD. (C) Imidazolone in the peritoneum of a rat that was treated with PD that contained PLP. (D) Imidazolone in the peritoneum of a rat that was treated with PD that contained HGF. (E) CML in the peritoneum of a rat that was treated with PS. (F) CML in the peritoneum of a rat that was treated with PD. (G) CML in the peritoneum of a rat that was treated with PD that contained PLP. (H) CML in the peritoneum of a rat that was treated with PD that contained HGF. (I) Type I collagen in the peritoneum of a rat that was treated with PS. (J) Type I collagen in the peritoneum of a rat that was treated with PD. (K) Type I collagen in the peritoneum of a rat that was treated with PD that contained PLP. (L) Type I collagen in the peritoneum of a rat that was treated with PD that contained HGF. Magnification, x100.
Expression of TGF-1 was much more prominent in the PD groupthan in the PS group. Administration of PLP and HGF inhibitedits expression in the visceral peritoneum. The inhibitory effectof TGF-1 was more prominent in the HGF group than in the PLPgroup (Table 1, Figure 4, A through D). It is interesting thatmarked HGF expression was noted in the peritoneum of the PLPgroup compared with that of the PD group, whereas its expressiondid not differ between the PD and the PS groups (Table 1, Figure 4,E through H). The intensity of VEGF expression and the numberof blood vessels in the visceral peritoneum did not differ amongthe four groups (data not shown), so they were reassessed usingthe parietal peritoneum. Expression of VEGF was increased inthe peritoneum of the PD group as compared with the PS group.Administration of PLP and HGF reduced expression of VEGF ascompared with the PD group (Table 1, Figure 5, A through D).The number of blood vessels was increased in the parietal peritoneumof PD-treated rats than in PS-treated rats. Administration ofPLP and HGF significantly inhibited an increase in the numberof blood vessels in the peritoneum as compared with the PD group(Table 1, Figure 5, E through H).
Figure 4. Light microscopic pictures of TGF-1 and HGF expression in the visceral peritoneum. (A) TGF-1 in the peritoneum of a rat that was treated with PS. (B) TGF-1 in the peritoneum of a rat that was treated with PD. (C) TGF-1 in the peritoneum of a rat that was treated with PD that contained PLP. (D) TGF-1 in the peritoneum of a rat that was treated with PD that contained HGF. (E) HGF in the peritoneum of a rat that was treated with PS. (F) HGF in the peritoneum of a rat that was treated with PD. (G) HGF in the peritoneum of a rat that was treated with PD that contained PLP. (H) HGF in the peritoneum of a rat that was treated with PD that contained HGF. Magnification, x100.
Figure 5. Light microscopic pictures of vascular endothelial growth factor (VEGF) expression and blood vessels in the parietal peritoneum. (A) VEGF in the peritoneum of a rat that was treated with PS. (B) VEGF in the peritoneum of a rat that was treated with PD. (C) VEGF in the peritoneum of a rat that was treated with PD that contained PLP. (D) VEGF in the peritoneum of a rat that was treated with PD that contained HGF. (E) Blood vessels in the peritoneum of a rat that was treated with PS. (F) Blood vessels in the peritoneum of a rat that was treated with PD. (G) Blood vessels in the peritoneum of a rat that was treated with PD that contained PLP. (H) Blood vessels in the peritoneum of a rat that was treated with PD that contained HGF. Magnification, x50.
AGE are considered to be involved in diabetic complicationsand aging, and their accumulation in living tissues leads topathologic tissue damage and organ dysfunction (8,23). Glucose-basedPD is toxic for mesothelial cells, stimulating them to releasegrowth factors and to produce matrix proteins in which bothhigh glucose and GDP are involved (24). High levels of GDP producedin PD during the heat-sterilization process accelerate formationof AGE (2). The localization of AGE detected using the antibodiesagainst CML and imidazolone was identical with that of growthfactors, and the intensity of accumulation was associated withperitoneal dysfunction (18). Thus, accumulation of AGE in peritonealtissues is associated with peritoneal histologic alterationsand ultrafiltration failure in CAPD patients. AGE alter cellularfunctions, including signal transduction pathway (25), and induceexpression of various growth factors, resulting in peritonealsclerosis and/or fibrosis with a loss of ultrafiltration.
Reduction of GDP levels may protect the peritoneum from accumulationof AGE in the peritoneum. Because hydrazine compounds such asaminoguanidine and OPB-9195 trap PL and consequently inducevitamin B6 deficiency, they are not yet used for the treatmentof AGE-related disorders such as diabetic complications (26).Vitamin B6 itself has been known to show preventive effectson coronary heart disease (27) and diabetic retinopathy (28).Recently, a vitamin B6 derivative, PM, was demonstrated to inhibitAGE formation and lipid peroxidation reaction (10,29,30). Moreover,this agent prevented the development of diabetic complicationsand hyperlipidemia in experimental rats (11,12). PLP competeswith sugars for Schiff base formation with protein amino groups(31,32), especially with an active lysine residue (33,34). Namely,decreased accumulation of CML can be explained by the bindingof the aldehyde group in PLP to protein amino groups, protectingthe peritoneum from modification by CML. However, the inhibitionof imidazolone accumulation needs another mechanism, becauseimidazolone mostly arises from 3DG as its precursor (20). Inthis study, we compared 3DG-trapping ability among the threevitamin B6 derivatives and first discovered a remarkable 3DG-trappingcapability of PLP compared with the other vitamin B6 derivatives,PL and PM. Decreased accumulation of imidazolone in the PLPgroup seems to be caused by its 3DG-trapping effect that isone of the characteristics of PLP. The inhibitory effect ofglycation differs between PLP and PL (14). In the present study,we could not confirm the precise mechanism of PLP to trap 3DG;however, it is certain that the 3DG-trapping ability differsbetween PLP and PL, suggesting that the phosphate group in PLPstructure plays an important role in the process of trapping3DG.
TGF-1 is a predominant fibrogenic factor that simultaneouslysuppresses HGF production in a reciprocal manner (17,35,36).VEGF induces vascular fenestrations (37,38), hyperpermeability(39,40), and neovascularization in the peritoneum of experimentalanimals (39,40) and CAPD patients (41). In the experiment ofgene transfer to the rat peritoneum, TGF-1 induced submesothelialzone thickening and decreased ultrafiltration, and the exposureto TGF-1 increased VEGF expression by mesothelial cells (39).Recently, it was demonstrated that expression of VEGF is upregulatedby not only glucose but also GDP (24,42) and glycated proteins(43). A recent immunohistochemical approach using serial sectionsrevealed that AGE promote expressions of TGF-1 and VEGF andthat the proliferation of myofibroblasts plays a crucial rolein morphologic peritoneal alterations and low ultrafiltrationcapacity in CAPD patients (18). In the present study, imidazoloneand CML were co-localized with TGF-1 and VEGF. It is noteworthythat administration of PLP significantly attenuated the expressionof these growth factors. Moreover, administration of PLP decreasedthe number of blood vessels and expression of VEGF in the peritoneum.Thus, PLP inhibits AGE modification of the peritoneum and consequentlyattenuates the expression of growth factors and neoangiogenesis.On the basis of reciprocal balance between TGF-1 and HGF, asuppression of TGF-1 increases HGF expression in the peritoneumof PLP-treated rats.
HGF plays a crucial role in the repairing process of tissues(44,45). In experimental renal disease, the therapeutic valueof HGF was established at relatively high doses of 500 µgto 5 mg/kg per d (17,46,47). In our study, HGF significantlyprevented the development of histologic alterations in the ratperitoneum induced by PD injection at a lower dose of 4 µg/kgper d. Direct administration of HGF on targeting tissue maysave its therapeutic dose, and the present study provides anew prospect for HGF therapy. Production of angiogenic cytokineincreases after TGF-1 exposure (39). Inhibition of TGF-1 expressionmay suppress VEGF production, resulting in decreased neoangiogenesis.Unexpectedly, accumulation of AGE was significantly reducedin the peritoneum of rats that were treated with HGF. As shownin Table 1 and Figure 2, the proliferation of type I collagenin the peritoneum of PD-treated rats was clearly inhibited bytreatment with HGF as well as PLP. Moreover, that inhibitionwas more prominent in HGF-treated rats than in PLP-treated rats.We speculate that treatment with HGF inhibits proliferationof extracellular matrix, a target for AGE modification, in theperitoneum and consequently reduces accumulation of AGE in extracellularmatrix.
In summary, we demonstrated for the first time that PLP inhibitsformation of AGE by trapping 3DG. More notable, PLP and HGFprevented the progression of histologic alterations in the peritoneuminduced by PD. PLP and HGF are expected to be useful for preventingthe development of peritoneal damage in patients who are onlong-term CAPD, although further studies are indispensable.
Footnotes
Published online ahead of print. Publication date availableat www.jasn.org.
Schalkwijk CG, Posthuma N, ten Brink HJ, ter Wee PM, Teerlink T: Induction of 1, 2-dicarbonyl compounds, intermediates in the formation of advanced glycation endproducts, during heat-sterilization of glucose-based peritoneal dialysis fluids. Perit Dial Int 19: 325–333, 1999[Abstract/Free Full Text]
Tauer A, Knerr T, Niwa T, Schaub TP, Lage C, Passlick-Deetjen J, Pischetsrieder M: In vitro formation of N-(carboxymethyl)lysine and imidazolones under conditions similar to continuous ambulatory peritoneal dialysis. Biochem Biophys Res Commun 280: 1408–1414, 2001[CrossRef][Medline]
Nakamura S, Miyazaki S, Sasaki S, Morita T, Hirasawa Y, Niwa T: Localization of imidazolone in the peritoneum of CAPD patients. A factor for a loss of ultrafiltration. Am J Kidney Dis 38: S107–S110, 2001[Medline]
Honda K, Nitta K, Horita S, Yumura W, Nihei H, Nagai R, Ikeda K, Horiuchi S: Accumulation of advanced glycation end products in the peritoneal vasculature of continuous ambulatory peritoneal dialysis patients with low ultra-filtration. Nephrol Dial Transplant 14: 1541–1549, 1999[Abstract/Free Full Text]
Garcia-Lopez E, Lindholm B, Tranaeus A: Biocompatibility of new peritoneal dialysis solutions: Clinical experience. Perit Dial Int 20[Suppl 5]: 48–56, 2000
Linden T, Forsback G, Deppisch R, Henle T, Wieslander A: 3-Deoxyglucosone, a promoter of advanced glycation end products in fluids for peritoneal dialysis. Perit Dial Int 18: 290–293, 1998[Abstract/Free Full Text]
Sundaram S, Cendoroglo M, Cooker LA, Jaber BL, Faict D, Holmes CJ, Pereira BJ: Effect of two-chambered bicarbonate lactate-buffered peritoneal dialysis fluids on peripheral blood mononuclear cell and polymorphonuclear cell function in vitro. Am J Kidney Dis 30: 680–689, 1997[Medline]
Nakamura S, Makita Z, Ishikawa S, Yasumura K, Fujii W, Yanagisawa K, Kawata T, Koike T: Progression of nephropathy in spontaneous diabetic rats is prevented by OPB-9195, a novel inhibitor of advanced glycation. Diabetes 46: 895–899, 1997[Abstract]
Miyata T, Ueda Y, Asahi K, Izuhara Y, Inagi R, Saito A, Van Ypersele De Strihou C, Kurokawa K: Mechanism of the inhibitory effect of OPB-9195 [(+/–)-2-isopropylidenehydrazono-4-oxo-thiazolidin-5-yla cetanilide] on advanced glycation end product and advanced lipoxidation end product formation. J Am Soc Nephrol 11: 1719–1725, 2000[Abstract/Free Full Text]
Booth AA, Khalifah RG, Todd P, Hudson BG: In vitro kinetic studies of formation of antigenic advanced glycation end products (AGEs). J Biol Chem 272: 5430–5437, 1997[Abstract/Free Full Text]
Stitt A, Gardiner TA, Alderson NL, Canning P, Frizzell N, Duffy N, Boyle C, Januszewski AS, Chachich M, Baynes JW, Thorpe SR: The AGE inhibitor pyridoxamine inhibits development of retinopathy in experimental diabetes. Diabetes 51: 2826–2832, 2002[Abstract/Free Full Text]
Alderson NL, Chachich ME, Youssef NN, Beattie RJ, Nachtigal M, Thorpe SR, Baynes JW: The AGE inhibitor pyridoxamine inhibits lipemia and development of renal and vascular disease in Zucker obese rats. Kidney Int 63: 2123–2133, 2003[CrossRef][Medline]
Nagaraj RH, Sarkar P, Mally A, Biemel KM, Lederer MO, Padayatti PS: Effect of pyridoxamine on chemical modification of proteins by carbonyls in diabetic rats: Characterization of a major product from the reaction of pyridoxamine and methylglyoxal. Arch Biochem Biophys 402: 110–119, 2002[CrossRef][Medline]
Khatami M, Suldan Z, David I, Li W, Rocky JH: Inhibitory effects of pyridoxal phosphate, ascorbate and aminoguanidine on nonenzymatic glycosylation. Life Sci 43: 1725–1731, 1988[CrossRef][Medline]
Ganea E, Rixon KC, Harding JJ: Binding of glucose, galactose and pyridoxal phosphate to lens crystallins. Biochim Biophys Acta 1226: 286–290, 1994[Medline]
Lehman TD, Ortwerth BJ: Inhibitors of advanced glycation end product-associated protein cross-linking. Biochim Biophys Acta 1535: 110–119, 2001[Medline]
Mizuno S, Matsumoto K, Kurosawa T, Mizuno-Horikawa Y, Nakamura T: Reciprocal balance of hepatocyte growth factor and transforming growth factor-1 in renal fibrosis in mice. Kidney Int 57: 937–948, 2000[Medline]
Nakamura S, Tachikawa T, Tobita K, Miyazaki S, Sakai S, Morita T, Hirasawa Y, Weigle B, Pischetsrieder M, Niwa T: Role of advanced glycation end products and growth factors in peritoneal dysfunction in CAPD patients. Am J Kidney Dis 41[Suppl 1]: S61–S67, 2003[CrossRef]
Ueda Y, Miyata T, Goffin E, Yoshino A, Inagi R, Ishibashi Y, Izuhara Y, Saito A, Kurokawa K, Van Ypersele De Strihou C: Effect of dwell time on carbonyl stress using icodextrin and amino acid peritoneal dialysis fluids. Kidney Int 58: 2518–2524, 2000[CrossRef][Medline]
Niwa T, Katsuzaki T, Miyazaki S, Miyazaki T, Ishizaki Y, Hayase F, Tatemichi N, Takei Y: Immunohistochemical detection of imidazolone, a novel advanced glycation end product, in kidneys and aortas of diabetic patients. J Clin Invest 99: 1272–1280, 1997[Medline]
Tsukushi S, Kajita M, Nakamura S, Niwa T: Gas chromatographic-mass spectrometric determination of erythrocyte 3-deoxyglucosone in diabetic patients. J Chromatogr B 776: 133–137, 2002
Niwa T, Sato M, Katsuzaki T, Tomoo T, Miyazaki T, Tatemichi N, Takei Y, Kondo T: Amyloid 2-microglobulin is modified with N-(carboxymethyl)lysine in dialysis-related amyloidosis. Kidney Int 50: 1303–1309, 1996[Medline]
Kirstein M, Brett J, Radoff S, Ogawa S, Stern D, Vlassara H: Advanced protein glycosylation induces transendothelial human monocyte chemotaxis and secretion of platelet-derived growth factor: Role in vascular disease of diabetes and aging. Proc Natl Acad Sci U S A 87: 9010–9014, 1990[Abstract/Free Full Text]
Ha H, Cha MK, Choi HN, Lee HB: Effect of peritoneal dialysis solutions on the secretion of growth factors and extracellular matrix proteins by human peritoneal mesothelial cells. Perit Dial Int 22: 171–177, 2002[Abstract/Free Full Text]
Kislinger T, Fu C, Huber B, Qu W, Taguchi A, Du Yan S, Hofmann M, Yan SF, Pischetsrieder M, Stern D, Schmidt AM: N-(carboxymethyl)lysine adducts of proteins are ligands for receptor for advanced glycation end products that activate cell signaling pathways and modulate gene expression. J Biol Chem 274: 31740–31749, 1999[Abstract/Free Full Text]
Taguchi T, Sugiura M, Hamada Y, Miwa I: Inhibition of advanced protein glycation by a Schiff base between aminoguanidine and pyridoxal. Eur J Pharmacol 378: 283–289, 1999[CrossRef][Medline]
Ellis JM, McCully KS: Prevention of myocardial infarction by vitamin B6. Res Commun Mol Pathol Pharmacol 89: 208–220, 1995[Medline]
Ellis JM, Folkers K, Minadeo M, VanBuskirk R, Xia LJ, Tamagawa H: A deficiency of vitamin B6 is a plausible molecular basis of the retinopathy of patients with diabetes mellitus. Biochem Biophys Res Commun 179: 615–619, 1991[CrossRef][Medline]
Metz TO, Alderson NL, Chachich ME, Thorpe SR, Baynes JW: Pyridoxamine traps intermediates in lipid peroxidation reactions in vivo. J Biol Chem 278: 42012–42019, 2003[Abstract/Free Full Text]
Heller JS, Canellakis ES, Bussolotti DL, Coward JK: Stable multisubstrate adducts as enzyme inhibitors—Potent inhibition of ornithine decarboxylase by N-(5'-phosphopyridoxyl)-ornithine. Biochim Biophys Acta 403: 197–207, 1975[Medline]
Kupfer A, Gani V, Shaltiel S: Micelles of pyridoxal-5'-phosphate Schiff bases—An improved model for the B6 site of glycogen phosphorylase. Biochem Biophys Res Commun 79: 1004–1010, 1977[CrossRef][Medline]
Potter D, Wojnar JM, Narasimhan C, Miziorko HM: Identification and functional characterization of an active-site lysine in mevalonate kinase. J Biol Chem 272: 5741–5746, 1997[Abstract/Free Full Text]
Bohney JP, Fonda ML, Feldhoff RC: Identification of Lys190 as the primary binding site for pyridoxal 5'-phosphate in human serum albumin. FEBS Lett 298: 266–268, 1992[CrossRef][Medline]
Matsumoto K, Nakamura T: Hepatocyte growth factor: Renotropic role and potential therapeutics for renal disease. Kidney Int 59: 2023–2038, 2001[Medline]
Nakano N, Morishita R, Moriguchi A, Nakamura Y, Higashi S, Aoki M, Kida I, Matsumoto K, Nakamura T, Higashi J, Ogihara T: Native regulation of local hepatocyte growth factor expression by angiotensin II and transforming growth factor- in blood vessels—Potential role of HGF in cardiovascular disease. Hypertension 32: 444–451, 1998[Abstract/Free Full Text]
Roberts WG, Palade GE: Increased microvascular permeability and endothelial fenestration induced by vascular endothelial growth factor. J Cell Sci 108: 2369–2379, 1995[Abstract]
Roberts WG, Palade GE: Neovasculature induced by vascular endothelial growth factor is fenestrated. Cancer Res 57: 765–772, 1997[Abstract/Free Full Text]
Margetts PJ, Kolb M, Galt T, Hoff CM, Shockley TR, Gauldie J: Gene transfer of transforming growth factor-1 to the rat peritoneum: Effects on membrane function. J Am Soc Nephrol 12: 2029–2039, 2001[Abstract/Free Full Text]
Vriese AS, Tilton RG, Stephan CC, Lameire NH: Vascular endothelial growth factor is essential for hyperglycemia-induced structural and functional alterations of the peritoneal membrane. J Am Soc Nephrol 12: 1734–1741, 2001[Abstract/Free Full Text]
Combet S, Miyata T, Moulin P, Pouthier D, Goffin E, Devuyst O: Vascular proliferation and enhanced expression of endothelial nitric oxide synthase in human peritoneum exposed to long-term peritoneal dialysis. J Am Soc Nephrol 11: 717–728, 2000[Abstract/Free Full Text]
Inagi R, Miyata T, Yamamoto T, Suzuki D, Urakami K, Saito A, van Ypersele de Strihou C, Kurokawa K: Glucose degradation product methylglyoxal enhances the production of vascular endothelial growth factor in peritoneal cells: Role in the functional and morphological alterations of peritoneal membranes in peritoneal dialysis. FEBS Lett 463: 260–264, 1999[CrossRef][Medline]
Mandl-Weber S, Cohen CD, Haslinger B, Kretzler M, Sitter T: Vascular endothelial growth factor production and regulation in human peritoneal mesothelial cells. Kidney Int 61: 570–578, 2002[CrossRef][Medline]
Liu Y, Rajur K, Tolbert E, Dworkin LD: Endogenous hepatocyte growth factor ameliorates chronic renal injury by activating matrix degradation pathways. Kidney Int 58: 2028–2043, 2000[CrossRef][Medline]
Rabkin R, Fervenza F, Tsao T, Sibley R, Friedlaender M, Hsu F, Lassman C, Hausmann M, Huie P, Schwall RH: Hepatocyte growth factor receptor in acute tubular necrosis. J Am Soc Nephrol 12: 531–540, 2001[Abstract/Free Full Text]
Mizuno S, Matsumoto K, Nakamura T: Hepatocyte growth factor suppresses interstitial fibrosis in a mouse model of obstructive nephropathy. Kidney Int 59: 1304–1314, 2001[CrossRef][Medline]
Inoue T, Okada H, Kobayashi T, Watanabe Y, Kanno Y, Kopp JB, Nishida T, Takigawa M, Ueno M, Nakamura T, Suzuki H: Hepatocyte growth factor counteracts transforming growth factor-1, through attenuation of connective tissue growth factor induction, and prevents renal fibrogenesis in 5/6 nephrectomized mice. FASEB J 17: 268–270, 2003[Abstract/Free Full Text]
Received for publication February 15, 2004.
Accepted for publication September 28, 2004.
This article has been cited by other articles:
S. Nakamura, H. Li, A. Adijiang, M. Pischetsrieder, and T. Niwa Pyridoxal phosphate prevents progression of diabetic nephropathy
Nephrol. Dial. Transplant.,
August 1, 2007;
22(8):
2165 - 2174.
[Abstract][Full Text][PDF]
Top
Abstract
Introduction
1. First, with the use of gas chromatography-mass spectrometry, whether PLP traps 3-deoxyglucosone (3DG), a major glucose degradation product in PD, was determined. Then, whether rat peritoneal tissue damages induced by intraperitoneal administration of glucose-based PD is ameliorated by PLP or HGF was examined. In vitro incubation with PLP markedly decreased concentration of 3DG in a dose-dependent manner, demonstrating the 3DG-trapping effect of PLP. The peritoneum of PD-treated rats was significantly thickened compared with that of physiologic saline-treated rats. Both PLP and HGF prevented the thickening of rat peritoneum induced by PD and ameliorated accumulation of AGE and expression of TGF-
-(carboxymethyl) lysine (CML) antibody (1:200) were prepared. These two anti-AGE antibodies were produced at our laboratory, and their epitopes and reactivity were characterized (20,22). For determining the expression of TGF-
antibody, and a monoclonal anti-VEGF antibody (1:20; Santa Cruz Biotechnology, Santa Cruz, CA) were used, respectively. For clarifying the location of blood vessels, a polyclonal anti-von Willebrand factor antibody (1:200; DAKO, Glostrup, Denmark) was used. Localization of type I collagen in the peritoneum was detected using a polyclonal anti-rat collagen I antibody (1:20; Sanbio bv, Am Uden, Netherlands). 
, PLP; 
, PL; 
, PM; *P < 0.05, ** P < 0.01, P *** < 0.001 compared with 0 mM
