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Role of Tamm-Horsfall protein and uromodulin in calcium oxalate crystallization
Carvalho, M.;Mulinari, R.A.;Nakagawa, Y.;
Brazilian Journal of Medical and Biological Research , 2002, DOI: 10.1590/S0100-879X2002001000009
Abstract: one of the defenses against nephrolithiasis is provided by macromolecules that modulate the nucleation, growth, aggregation and retention of crystals in the kidneys. the aim of the present study was to determine the behavior of two of these proteins, tamm-horsfall and uromodulin, in calcium oxalate crystallization in vitro. we studied a group of 10 male stone formers who had formed at least one kidney stone composed of calcium oxalate. they were classified as having idiopathic nephrolithiasis and had no well-known metabolic risk factors involved in kidney stone pathogenesis. ten normal men were used as controls, as was a group consisting of five normal women and another consisting of five pregnant women. crystallization was induced by a fixed supersaturation of calcium oxalate and measured with a coulter counter. all findings were confirmed by light and scanning electron microscopy. the number of particulate material deposited from patients with tamm-horsfall protein was higher than that of the controls (p<0.001). however, tamm-horsfall protein decreased the particle diameter of the stone formers when analyzed by the mode of the volume distribution curve (p<0.002) (5.64 ± 0.55 μm compared to 11.41 ± 0.48 μm of uromodulin; 15.94 ± 3.93 μm and 12.45 ± 0.97 μm of normal men tamm-horsfall protein and uromodulin, respectively; 8.17 ± 1.57 μm and 9.82 ± 0.95 μm of normal women tamm-horsfall protein and uromodulin, respectively; 12.17 ± 1.41 μm and 12.99 ± 0.51 μm of pregnant tamm-horsfall protein and uromodulin, respectively). uromodulin produced fewer particles than tamm-horsfall protein in all groups. nonetheless, the total volume of the crystals produced by uromodulin was higher than that produced by tamm-horsfall protein. our results indicate a different effect of tamm-horsfall protein and uromodulin. this dual behavior suggests different functions. tamm-horsfall protein may act on nucleation and inhibit crystal aggregation, while uromodulin may promote aggregation of
Role of Tamm-Horsfall protein and uromodulin in calcium oxalate crystallization  [cached]
Carvalho M.,Mulinari R.A.,Nakagawa Y.
Brazilian Journal of Medical and Biological Research , 2002,
Abstract: One of the defenses against nephrolithiasis is provided by macromolecules that modulate the nucleation, growth, aggregation and retention of crystals in the kidneys. The aim of the present study was to determine the behavior of two of these proteins, Tamm-Horsfall and uromodulin, in calcium oxalate crystallization in vitro. We studied a group of 10 male stone formers who had formed at least one kidney stone composed of calcium oxalate. They were classified as having idiopathic nephrolithiasis and had no well-known metabolic risk factors involved in kidney stone pathogenesis. Ten normal men were used as controls, as was a group consisting of five normal women and another consisting of five pregnant women. Crystallization was induced by a fixed supersaturation of calcium oxalate and measured with a Coulter Counter. All findings were confirmed by light and scanning electron microscopy. The number of particulate material deposited from patients with Tamm-Horsfall protein was higher than that of the controls (P<0.001). However, Tamm-Horsfall protein decreased the particle diameter of the stone formers when analyzed by the mode of the volume distribution curve (P<0.002) (5.64 ± 0.55 μm compared to 11.41 ± 0.48 μm of uromodulin; 15.94 ± 3.93 μm and 12.45 ± 0.97 μm of normal men Tamm-Horsfall protein and uromodulin, respectively; 8.17 ± 1.57 μm and 9.82 ± 0.95 μm of normal women Tamm-Horsfall protein and uromodulin, respectively; 12.17 ± 1.41 μm and 12.99 ± 0.51 μm of pregnant Tamm-Horsfall protein and uromodulin, respectively). Uromodulin produced fewer particles than Tamm-Horsfall protein in all groups. Nonetheless, the total volume of the crystals produced by uromodulin was higher than that produced by Tamm-Horsfall protein. Our results indicate a different effect of Tamm-Horsfall protein and uromodulin. This dual behavior suggests different functions. Tamm-Horsfall protein may act on nucleation and inhibit crystal aggregation, while uromodulin may promote aggregation of calcium oxalate crystals.
Qualification and application of an ELISA for the determination of Tamm Horsfall Protein (THP) in human urine and its use for screening of Kidney Stone Disease
Wai-Hoe Lau, Wing-Seng Leong, Zhari Ismail, Lay-Harn Gam
International Journal of Biological Sciences , 2008,
Abstract: Kidney stone disease affects 1 - 20% of the general population. At present, the diagnosis of a stone is done using radiography method when noticeable symptoms appeared. We developed a non-invasive quantitative assay for urinary THP, namely ELISA; whereby our previous study and other reports had shown the usefulness of THP as biomarker for kidney stone disease. Since urine is biological fluid that is easily obtainable, this method could be used as a screening assay for kidney stone prior to confirmation with radiography. The ELISA gave assay linearity r2 > 0.999 within the range of 109 ng/mL to 945 ng/mL THP. Assay precisions were < 4% (C.V.) for repeatability and < 5% (C.V.) for reproducibility. Assay accuracy range from 97.7% to 101.2% at the various THP concentrations tested. Assay specificity and sensitivity were 80% and 86%, respectively. The cut-off points at P < 0.05 were 37.0 and 41.2 μg/mL for male and female, respectively. The assay is cost effective and rapid whereby the cost for assaying each urine sample in duplicate is approximately USD0.35 and within 5 hours, 37 samples can be assayed alongside full range of standards and 3 QC samples in each plate. Furthermore, sample preparation is relatively easy where urine sample was diluted 10 times in TEA buffer. The usability of the ELISA method for diagnosis of kidney stone disease is evaluated with 117 healthy subjects and 58 stone formers.
Tamm-Horsfall protein facilitates catheter associated urinary tract infection
Hajamohideen S Raffi, James M Bates, Dayl J Flournoy, Satish Kumar
BMC Research Notes , 2012, DOI: 10.1186/1756-0500-5-532
Abstract: Twenty one urinary catheters were obtained from 20 hospitalized patients. THP was eluted from the catheter surface and catheter segments were cultured. Additional studies were performed in vitro on unused silicone and latex catheters to determine the binding of THP, and the effect of THP on the binding of Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa), to the catheter surface.On catheters obtained from patients, the THP deposition was significantly more on culture positive catheters than on culture negative catheters. In the in vitro studies, THP bound to both silicone and latex catheters, and THP enhanced the adherence of E. coli and P. aeruginosa to both types of catheters.THP binds to urinary catheters and facilitates the binding of uropathogenic bacteria to catheters.Catheter Associated Urinary Tract Infection (CAUTI) is a common hospital acquired infection. Urinary catheters are placed in one of four hospitalized patients in the United States [1]. About 26% of catheterized patients develop asymptomatic catheter associated bacteriuria (CAB) of which 24% progress to symptomatic CAUTI [2]. CAUTI accounts for 40% of all hospital acquired infections [3,4] and 80% of all hospital acquired urinary tract infections (UTI) [5]. In adult intensive care units, more than 95% of urinary tract infections are caused by urinary catheters [6].Tamm-Horsfall protein (THP) is the most abundant protein in normal urine with multiple postulated biological functions [7-9]. THP is a glycoprotein with a variety of n-linked and o-linked glycans that give it a versatile ability to bind a variety of substances [7,8]. We [10] and others [11] have previously shown that THP plays a defensive role against UTI presumably by binding uropathogenic bacteria and helping to clear them from the urinary tract.The role of THP as a host defense factor against UTI has not been studied in the presence of an in-dwelling urinary catheter. The abundance of THP in urine and its tendency
Stabilization of Submicron Calcium Oxalate Suspension by Chondroitin Sulfate C May Be an Efficient Protection from Stone Formation  [PDF]
Jun-Jun Li,Jun-Fa Xue,Jian-Ming Ouyang
Bioinorganic Chemistry and Applications , 2013, DOI: 10.1155/2013/360142
Abstract: The influences of chondroitin sulfate C (C6S) on size, aggregation, sedimentation, and Zeta potential of sub-micron calcium oxalate monohydrate (COM) and calcium oxalate dihydrate (COD) crystallites with mean sizes of about 330?nm were investigated using an X-ray diffractometer, nanoparticle size Zeta potential analyzer, ultraviolet spectrophotometer, and scanning electron microscope, after which the results were compared with those of micron-grade crystals. C6S inhibited the conversion of COD to COM and the aggregation of COM and COD crystallitesis; it also decreased their sedimentation rate, thus increasing their stability in aqueous solution. The smaller the size of the COD crystallites, the easier they can be converted to COM. The stability of sub-micron COD was worse than that of micron-grade crystals. C6S can inhibit the formation of calcium oxalate stones. 1. Introduction The formation of urinary stones is closely related to supersaturation, nucleation, growth, and aggregation of stone salt. Compared with the urine of stone patients, normal urine has more types of inhibitors with higher concentration and stronger activity. These inhibitors include some small-molecule inorganic salts such as citrate and pyrophosphate and urinary macromolecules such as glycosaminoglycan (GAG), nephrocalcin, Tamm-Horsfall protein, and prothrombin fragment 1 [1–5]. As the main component of urinary stones, calcium oxalate (CaOxa) mainly exists in the form of calcium oxalate monohydrate (COM) and calcium oxalate dehydrate (COD). In the urine of patients afflicted with urinary stones, the existing probability of COM crystallites is much higher than that in healthy controls [6]. A study showed that CaOxa crystals in urine only take 3?min to 4?min to flow through the nephron [7] and about 12?min to pass through the pelvis. Within such a short time, the crystal could not grow into a pathological size (larger than tens of microns). Rapid aggregation of the crystals is an important factor in CaOxa stone formation [8, 9]. GAG is an important urinary macromolecule that inhibits urinary stone formation [2]. Urinary GAGs originate from two sources. The first source of urinary GAGs is the serum, which is filtered through the kidney into the urine. The electrophoretic types of GAGs in urine are similar to those present in the serum; moreover, the excretion of urinary GAGs increases along with the increment of GAG concentration in the serum [10–12]. The GAGs in the serum originate from degradation products of proteoglycans in connective tissues, such as the cartilage,
Role of Tamm-Horsfall protein in the binding and in vivo phagocytosis of type 1 fimbriated Escherichia coli by mouse peritoneal macrophages
Bastos, A.C.S.C.;Santos, L.B.;Tamashiro, W.M.S.C.;Yamada, A.T.;Oliveira, U.M.;Yano, T.;
Brazilian Journal of Medical and Biological Research , 2001, DOI: 10.1590/S0100-879X2001000700011
Abstract: tamm-horsfall glycoprotein (thp) contains manno-oligosaccharides that are recognized by type 1 fimbriae (f1) of escherichia coli. in the present study, we examined the in vivo phagocytic activity of mouse peritoneal macrophages after treatment of bacteria with thp. at low thp concentrations (12.5 μg/ml and 50 μg/ml) no significant difference was observed in the phagocytosis of e. coli f1+. however, at high thp concentrations (500 μg/ml and 1250 μg/ml) we obtained a reduction of bacterial phagocytosis by mouse peritoneal macrophages.
Role of Tamm-Horsfall protein in the binding and in vivo phagocytosis of type 1 fimbriated Escherichia coli by mouse peritoneal macrophages  [cached]
Bastos A.C.S.C.,Santos L.B.,Tamashiro W.M.S.C.,Yamada A.T.
Brazilian Journal of Medical and Biological Research , 2001,
Abstract: Tamm-Horsfall glycoprotein (THP) contains manno-oligosaccharides that are recognized by type 1 fimbriae (F1) of Escherichia coli. In the present study, we examined the in vivo phagocytic activity of mouse peritoneal macrophages after treatment of bacteria with THP. At low THP concentrations (12.5 μg/ml and 50 μg/ml) no significant difference was observed in the phagocytosis of E. coli F1+. However, at high THP concentrations (500 μg/ml and 1250 μg/ml) we obtained a reduction of bacterial phagocytosis by mouse peritoneal macrophages.
Tamm-Horsfall Glycoprotein Enhances PMN Phagocytosis by Binding to Cell Surface-Expressed Lactoferrin and Cathepsin G That Activates MAP Kinase Pathway  [PDF]
Syue-Cian Siao,Ko-Jen Li,Song-Chou Hsieh,Cheng-Han Wu,Ming-Chi Lu,Chang-Youh Tsai,Chia-Li Yu
Molecules , 2011, DOI: 10.3390/molecules16032119
Abstract: The molecular basis of polymorphonuclear neutrophil (PMN) phagocytosis-enhancing activity (PEA) by human purified urinary Tamm-Horsfall glyco- protein (THP) has not been elucidated. In this study, we found human THP bound to lactoferrin (LF) and cathepsin G (CG) expressed on the surface of PMN, identified by a proteomic study with MALDI-TOF- LC/LC/mass spectrometric analysis. Pre-incubation of 10% SDS-PAGE electrophoresed PMN lysates with monoclonal anti-LF or anti-CG antibody reduced the binding with THP. To elucidate the signaling pathway of THP on PMN activation, we found THP enhanced ERK1/2 phosphorylation, reduced p38 MAP kinase phosphorylation, but had no effect on DNA binding of the five NF-kB family members in PMN. To further clarify whether the carbohydrate-side chains or protein-core structure in THP molecule is responsible for THP-PEA, THP was cleaved by different degrading enzymes with carbohydrate specificity (neuraminidase and β-galactosidase), protein specificity (V8 protease and proteinase K) or glycoconjugate specificity (carboxylpeptidase Y and O-sialoglycoprotein endopeptidase). We clearly demonstrated that the intact protein-core structure in THP molecule was more important for THP-PEA than carbohydrate-side chains. Putting these results together, we conclude that THP adheres to surface-expressed LF and CG on PMN and transduces signaling via the MAP kinase pathway to enhance PMN phagocytosis.
SDS-PAGE-Based Quantitative Assay for Screening of Kidney Stone Disease
Lau Wai-Hoe, Leong Wing-Seng, Zhari Ismail, Gam Lay-Harn
Biological Procedures Online , 2009, DOI: 10.1007/s12575-009-9007-y
Abstract: Pathogenesis of kidney stone disease involves nucleation, growth, aggregation, and retention of crystals in the kidney. Biochemical tests for urinary electrolytes cannot specifically identify the formation of stone in the kidney. In human, the mechanism against the formation of kidney stone involves macromolecules, i.e., protein and glycosaminoglycan that are polyanionic molecules with substantial amounts of acidic amino acid residues that inhibit crystal aggregation [1]. Tamm Horsfall glycoprotein (THP) is one of the inhibitors to crystalize aggregation in kidney [2,3].Tamm Horsfall glycoprotein is the most abundant urinary protein in healthy individual [4,5]. It is excreted by the thick ascending limb of the loop of Henle [6]. THP is excreted in urine at a rate of ~50 mg/day and can be influenced by many factors including urine volume, diet, and exercise [7]. THP has a molecular weight of ~85 kDa although inclines to form macroaggregates of several million Daltons [8]. THP is heavily glycosylated by N-linked glycans that account for about 30% of its molecular weight [9]. Kidney stone patients excrete THP molecules lacking terminally linked sialic acid that reduces its inhibitory activity against stone formation [10]. Although reduced urinary THP excretion in stone patients had been documented [11-13], quantitative analysis of THP by using electroimmunodiffusion shown no changes in THP excretion levels between stone patients and healthy subjects [14,15]. Other studies by using radioimmunoassay and ELISA shown that THP excretion was inconsistent or reduced in stone patients [17-19] compared to the healthy subjects [16]. In the studies where analysis of THP was carried out by using SDS-PAGE, Yokomizoi et al. [11] showed that THP intensity in stone patients was lower than that of healthy subjects while Pourmand et al. [20] stated there was no significant difference in THP excretion between the two cohorts. In our earlier study, we had reported that THP can be used to
EGF Receptor-Dependent Mechanism May be Involved in the Tamm–Horsfall Glycoprotein-Enhanced PMN Phagocytosis via Activating Rho Family and MAPK Signaling Pathway  [PDF]
Ko-Jen Li,Sue-Cien Siao,Cheng-Han Wu,Chieh-Yu Shen,Tsai-Hung Wu,Chang-Youh Tsai,Song-Chou Hsieh,Chia-Li Yu
Molecules , 2014, DOI: 10.3390/molecules19011328
Abstract: Our previous studies showed that urinary Tamm–Horsfall glycoprotein (THP) potently enhanced polymorphonuclear neutrophil (PMN) phagocytosis. However, the domain structure(s), signaling pathway and the intracellular events responsible for THP-enhanced PMN phagocytosis remain to be elucidated. THP was purified from normal human urine. The human promyelocytic leukemia cell line HL-60 was induced to differentiate into PMNs by all-trans retinoid acid. Pretreatment with different MAPK and PI3K inhibitors was used to delineate signaling pathways in THP-enhanced PMN phagocytosis. Phosphorylation of molecules responsible for PMN phagocytosis induced by bacterial lipopolysaccharide (LPS), THP, or human recombinant epidermal growth factor (EGF) was evaluated by western blot. A p38 MAPK inhibitor, SB203580, effectively inhibited both spontaneous and LPS- and THP-induced PMN phagocytosis. Both THP and LPS enhanced the expression of the Rho family proteins Cdc42 and Rac that may lead to F-actin re-arrangement. Further studies suggested that THP and EGF enhance PMN and differentiated HL-60 cell phagocytosis in a similar pattern. Furthermore, the EGF receptor inhibitor GW2974 significantly suppressed THP- and EGF-enhanced PMN phagocytosis and p38 and ERK1/2 phosphorylation in differentiated HL-60 cells. We conclude that EGF receptor-dependent signaling may be involved in THP-enhanced PMN phagocytosis by activating Rho family and MAP kinase.
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