Development of SCAR Markers to Identify Medicinal Cultivars of Paeonia lactiflora

Paeoniae Radix, the dried root of Paeonia lactiflora, is one of the most important ingredients in Kampo medicine. It is known that Paeoniae Radix is derived from various P. lactiflora cultivars, including medicinal and horticultural cultivars, and that cultivar identification by DNA analysis has been unsuccessful. We attempted to develop sequence characterized amplified region (SCAR) markers as useful DNA markers for the identification and herbal medicine authentication of two cultivars developed in Japan, 'Bonten' and 'Kitasaisho,' which are two superior medicinal strains of P. lactiflora. Sequence-related amplified polymorphism (SRAP) analysis was conducted on fourteen P. lactiflora cultivars, and polymorphic fragments specific to 'Bonten' or 'Kitasaisho' were detected. Then, SCAR markers for 'Bonten' and 'Kitasaisho' were developed from the sequence information of these polymorphic fragments. Thirty cultivars of P. lactiflora and five herbal medicine samples were used to validate the specificity of the developed SCAR markers. As a result, we confirmed that our SCAR markers can identify 'Bonten' or 'Kitasaisho' from the plant samples and the herbal medicine samples. Thus, we have successfully designed two highly specific DNA markers and established an easy, rapid, and cost-efficient method to identify specific cultivars of P. lactiflora. Our SCAR markers are expected to contribute to the maintenance of P. lactiflora cultivars such as 'Bonten' as superior medicinal strains, the development of more elite cultivars in the future, and the deterrence of outflow of original cultivars to foreign countries.

Efficient fertilization in the cultivation of Angelica acutiloba (Siebold & Zucc.) Kitag. in Hokkaido: Effect of amount of supplied nitrogen on growth, yield, and quality of A. acutiloba

Angelica acutiloba (Siebold & Zucc.) Kitag., the source plant of the crude drug Angelicae acutilobae radix, is traditionally cultivated in western regions of Japan. Since A. acutiloba is now also grown in Hokkaido, the northernmost prefecture of the country, the cultivation method, especially the quantity of fertilizer, needs to be adapted because of the cooler climate and shorter growing period. In this study, we compared plant growth and harvest yield of A. acutiloba cultivated with different amounts of nitrogen (N) fertilizer. When plants were fertilized with 24 kg N/10 a, the aerial part was lush, and the diameter at the top of the root was about 1.3 times thicker than that in plants treated with 12 kg N/10 a. On the other hand, the weight of the harvested root grown with 24 kg N/10 a was slightly, although not significantly, less than that in plants grown with 12 kg N/10 a. In addition, we found that the content of (Z)-ligustilide, a major essential oil contained in A. acutiloba root, is affected by nitrogen application. Interestingly, it increased with increasing amounts of supplied nitrogen. However, the importance of Angelicae acutilobae radix as the crude drug is not limited to its (Z)-ligustilide content, and there are also other crucial quality features, such as having thick lateral roots, which were generated in this study with a moderate nitrogen application. We conclude that about 12 kg N/10 a is the optimal amount of nitrogen for healthy growth of A. acutiloba in Hokkaido.

Polymorphism analysis of TCP gene region to intraspecific analysis of Paeonia lactiflora, and application for authentication of Paeoniae Radix

We attempted to conduct an intraspecific analysis of 30 peony cultivars in Japan and to authenticate five herbal medicine samples derived from Paeoniae Radix by polymorphism analysis of the TEOSINTE BRANCHED1, CYCLOIDEA, and PCF (TCP) gene region. We focused on cultivar-dependent differences in leaf margin undulation and analyzed the sequence of the related TCP gene region. As a result, we found that the nucleotide sequences of 29 cultivars of Paeonia lactiflora except 'America' exhibit interspecific variations compared with the nucleotide sequences of Paeonia suffruticosa and Paeonia tenuifolia. Therefore, in the dendrogram constructed on the basis of the sequence similarity in the TCP gene region, the 29 cultivars of P. lactiflora were separated from P. suffruticosa, P. tenuifolia, and 'America', and clustered into three subgroups. There were 16 variations containing heterogenous DNA sequences within P. lactiflora species, and two characteristic variations in subgroup I. Some P. lactiflora cultivars showed the same nucleotide sequence in the TCP gene region, whereas the five herbal medicine samples showed different sequences, although all of them could be authenticated. The results suggest that Paeoniae Radix in the Japanese crude drug market can be authenticated by analysis of the TCP gene region.

Simultaneous UHPLC/MS quantitative analysis and comparison of Saposhnikoviae radix constituents in cultivated, wild and commercial products

Differences in the components of the crude drug Saposhnikoviae radix, both wild and cultivated, and the cultivation duration were examined by UHPLC/MS. As a result, there was no significant difference in composition depending on the region in China where the drug was produced. The most abundant components in all samples were prim-O-glucosylcimifugin, 4'-O-glucosyl-5-O-methylvisamminol, 3'-O-acetylhamaudol and cimifugin. The 1 year-old Saposhnikoviae radix cultivated in Japan had a low component content overall. A comparison of components according to root thickness revealed that glycosides, such as prim-O-glucosylcimifugin and 4'-O-glucosyl-5-O-methylvisamminol, were accumulated in thin roots. In a comparison of the components according to the drying temperature, a large difference was observed in the content of glycosides, and a difference was observed depending on the sugar-binding position. According to a metabolome analysis in domestic commercial products by LC/MS, a characteristic component in the cultivated product was found and its content was low in the 1 year-old sample and high in the 2 year-old sample. If the cultivation duration is prolonged up to about 6 years, the contents of the ingredients are close to those of wild products.

New isoflavone glucosides in yabumame (Amphicarpaea bracteata (L.) Fernald subsp. edgeworthii (Benth.) H.Ohashi var. japonica (Oliv.) H.Ohashi) and their effect on leukotriene B4 production in mast cells

Yabumame (Amphicarpaea bracteata (L.) Fernald subsp. edgeworthii (Benth.) H.Ohashi var. japonica (Oliv.) H.Ohashi) is a legume plant that the Ainu people eat as a traditional food, although the bioactive ingredients other than vitamins have not been studied. In this study, the structures of yabumame isoflavone glucosides were determined and their effect on leukotriene (LT) B₄, a chemical mediator of type I allergy, produced in mast cells, was investigated in vitro. Seven compounds were isolated from yabumame. Their structures were determined by spectroscopic and spectrometric analyses, which were genistein-7-O-β-D-glucoside (1), formononetin-7-O-(2″-O-β-D-glucosyl)-β-D-glucoside (2), formononetin-7-O-β-D-glucoside (3), biochanin A-7-O-(2″-O-β-D-glucosyl)-β-D-glucoside (4), formononetin-7-O-(6″-O-malonyl)-β-D-glucoside (5), biochanin A-7-O-(2″-O-β-D-glucosyl-6″-O-β-D-glucosyl)-β-D-glucoside (6), and biochanin A-7-O-(6″-O-malonyl)-β-D-glucoside (7). Compounds 2, 4, and 6 were determined as new compounds. Compound 3 showed statistically significant suppressive effect on LTB₄ production in mast cells, although the activity was not strong. On the other hand, biochanin A, an aglycone common to compounds 4, 6, and 7, strongly inhibited the LTB₄ production. The results suggest that some of yabumame isoflavone glucosides might contribute to mitigate type I allergy. Seven isoflavone glucosides including 3 new compounds were found in yabumame and their anti-allergic effect was evaluated.

Evaluation of the safety and efficacy of Glycyrrhiza uralensis root extracts produced using artificial hydroponic-field hybrid cultivation systems II: comparison of serum concentration of glycyrrhetinic acid serum concentration in mice

To evaluate the safety and efficacy of Glycyrrhiza uralensis root produced using artificial hydroponic and artificial hydroponic-field hybrid cultivation systems, we investigated the pharmacokinetics of a major metabolite of glycyrrhizin (GL), glycyrrhetinic acid (GA). Hot water extracts obtained from the roots of the artificial hydroponic-field hybrid cultivated Glycyrrhiza uralensis were orally administered at a dose of 100 mg/kg as GL in mice and, compared with a commercial crude drug, Glycyrrhizae Radix. The temporal changes in serum GA concentration was found to depend on the GL concentration of the hot-water extracts. When hot-water extracts containing relatively high GL were administered, bimodal peaks appeared. In contrast, a broad single peak was detected when a hot-water extract containing relatively low GL content was administered. These tendencies in the serum GA concentration time course were observed for all samples, regardless of their derivation. Moreover, we compared the pharmacokinetic parameters and found that the C_max and AUC_0-48 values after oral administration of the extracts from Glycyrrhiza uralensis roots produced by the artificial cultivation system are within the range of variation for the commercial crude drugs. These results suggest the possibility that roots of Glycyrrhiza uralensis cultivated by the artificial hydroponic-field hybrid cultivation system can be used in addition to currently available commercial crude drugs produced from wild plant resources.

Determination of (E)-ferulic acid content in the root of Angelica acutiloba: a simple chemical evaluation method for crude drug quality control

The root of Angelica acutiloba Kitagawa is an important crude drug in Kampo medicines (traditional Japanese medicine). Chemical evaluation of crude drugs is crucial to ensuring the safety and efficacy of herbal medicine; however, there is currently no chemical standard for the A. acutiloba crude drug in Japanese pharmacopoeia. (E)-ferulic acid (FA) is an important active ingredient of Angelica spp., including A. sinensis (Oliv.) Diels, and has been suggested as a marker for quality evaluation of those crude drugs. However, it has been controversial whether FA is a reliable marker constituent of A. acutiloba. To achieve effective extraction of FA from A. acutiloba, we compared three different extraction methods: alkaline hydrolysis, ethanol extraction, and hexane extraction. FA levels in these extracts were assessed using high performance liquid chromatography (HPLC), and alkaline hydrolysis was found to be the most effective. Furthermore, in the hydrolysate, FA was distinctly identified by thin layer chromatography (TLC) analysis. These results provide useful information for the quality control of the A. acutiloba crude drug.

Evaluation of the safety and efficacy of Glycyrrhiza uralensis root extracts produced using artificial hydroponic and artificial hydroponic-field hybrid cultivation systems

Glycyrrhiza uralensis roots used in this study were produced using novel cultivation systems, including artificial hydroponics and artificial hydroponic-field hybrid cultivation. The equivalency between G. uralensis root extracts produced by hydroponics and/or hybrid cultivation and a commercial Glycyrrhiza crude drug were evaluated for both safety and efficacy, and there were no significant differences in terms of mutagenicity on the Ames tests. The levels of cadmium and mercury in both hydroponic roots and crude drugs were less than the limit of quantitation. Arsenic levels were lower in all hydroponic roots than in the crude drug, whereas mean lead levels in the crude drug were not significantly different from those in the hydroponically cultivated G. uralensis roots. Both hydroponic and hybrid-cultivated root extracts showed antiallergic activities against contact hypersensitivity that were similar to those of the crude drug extracts. These study results suggest that hydroponic and hybrid-cultivated roots are equivalent in safety and efficacy to those of commercial crude drugs. Further studies are necessary before the roots are applicable as replacements for the currently available commercial crude drugs produced from wild plant resources.

Prenylated benzophenones from Triadenum japonicum

Six new prenylated benzophenones, (-)-nemorosonol (1) and trijapins A-E (2-6), were isolated from the aerial parts of Triadenum japonicum. (-)-Nemorosonol (1) and trijapins A-C (2-4) have a common tricyclo[4.3.1.0(3,7)]decane skeleton, while 1 is an enantiomer of (+)-nemorosonol previously isolated from Clusia nemorosa. The absolute configuration of (-)-nemorosonol (1) was assigned by ECD spectroscopy. Trijapins A-C (2-4) are analogues of 1 possessing an additional tetrahydrofuran ring. Trijapins D (5) and E (6) are prenylated benzophenones with a 1,2-dioxane moiety and a hydroperoxy group, respectively. (-)-Nemorosonol (1) exhibited antimicrobial activity against Escherichia coli (MIC, 8 μg/mL), Staphylococcus aureus (MIC, 16 μg/mL), Bacillus subtilis (MIC, 16 μg/mL), Micrococcus luteus (MIC, 32 μg/mL), Aspergillus niger (IC50, 16 μg/mL), Trichophyton mentagrophytes (IC50, 8 μg/mL), and Candida albicans (IC50, 32 μg/mL), while trijapin D (5) showed antimicrobial activity against C. albicans (IC50, 8 μg/mL).

Highly oxygenated monoterpene acylglucosides from Spiraea cantoniensis

Six new monoterpene acylglucosides named kodemariosides A-F (1-6) were isolated from the leaves and flowers of Spiraea cantoniensis. Their absolute structures including a highly oxygenated monoterpene aglycon part were determined by NMR experiments and chemical derivatization.

Factors that contribute to faecal cyclooxygenase-2 mRNA expression in subjects with colorectal cancer

Background:

We previously reported that a faecal cyclooxygenase-2 (COX-2) mRNA assay was useful for identifying colorectal cancer (CRC). This study sought to investigate the factors that contribute to faecal COX-2 mRNA expression in subjects with CRC.

Methods:

The study cohort comprised 78 patients with CRC and 36 control subjects. The expressions of COX-2, β-2-microglobulin (B2M), carcinoembryonic antigen (CEA), E-cadherin (E-cad), and CD45 mRNA in faeces and COX-2 mRNA expression in tissue were determined by quantitative real-time RT–PCR.

Results:

The level of faecal expression of COX-2 mRNA in CRC was significantly higher than that in controls. A significant correlation was found between faecal COX-2 mRNA expression and faecal B2M, CEA, E-cad, or CD45 mRNAs, markers of exfoliated total cells, colonocytes, and leukocytes, respectively. A significant correlation was found between the expression of COX-2 mRNA in faeces and tumour surface area, COX-2 mRNA expression in primary tumour. There was no difference in faecal COX-2 mRNA expression between proximal CRC and distal CRC.

Conclusion:

COX-2 mRNA expression in faeces seems to originate from tumour lesion and to be affected by factors such as the number of exfoliated cells, exfoliation of inflammatory cells, COX-2 mRNA expression in tumour, and tumour size.

[13C]-pantoprazole breath test to predict CYP2C19 phenotype and efficacy of a proton pump inhibitor, lansoprazole

BACKGROUND

(13)CO(2) is produced on metabolism of (13)C-labelled-pantoprazole ([(13)C]-pantoprazole) by CYP2C19.

AIM

To investigate whether the [(13)C]-pantoprazole breath test can predict CYP2C19 status and efficacy of proton pump inhibitors (PPIs) in Japanese.

METHODS

We classified 110 healthy volunteers as rapid metabolizers (RM), intermediate metabolizers (IM) or poor metabolizers (PM) of CYP2C19 by genotyping. Breath samples were collected at 10-min intervals for 60 min after dosing with 100 mg [(13)C]-pantoprazole. Changes in the carbon isotope ratios ((13)CO(2)/(12)CO(2)) in carbon dioxide in breath samples were measured and expressed as a delta-over-baseline (DOB) ratio ( per thousand). Of the 110 subjects, twenty-two randomly selected subjects underwent intragastric pH monitoring on day 7 of dosing with 30 mg of lansoprazole.

RESULTS

The DOB values of RMs were the highest and those of PMs the lowest of the three groups. Statistically significant differences were observed in the area-under-the-curve (AUC)(20-60 min) of DOB among the three groups. The mean 24-h intragastric pHs attained by lansoprazole 30 mg for 7 days were inversely correlated with the AUC(20-60 min) of DOB.

CONCLUSIONS

[(13)C]-pantoprazole breath test can easily estimate the individual activity of CYP2C19 and predict the efficacy of a PPI (i.e. lansoprazole). This test would be useful for individualized medicine with a PPI.

Human Sgo1 downregulation leads to chromosomal instability in colorectal cancer

BACKGROUND AND AIMS

Chromosomal instability (CIN) is recognised as a hallmark of cancer and is caused by a spindle assembly checkpoint disorder or chromosome mis-segregation during mitosis. Although the recent identification of human shugoshin (hSgo1), an important player in proper chromosome segregation, has suggested the involvement of hSgo1 in colorectal tumourigenesis, little is known about how it is involved. The aim of this study was to obtain information about the status of hSgo1 in human colorectal cancer.

METHOD AND RESULTS

Among the 46 colorectal cancer cases, hSgo1 mRNA expression was decreased in the tumour tissue in comparison with the corresponding normal tissue (p = 0.032). Human Sgo1-downregulated tumours (tumour to normal mucosa ratio<0.5) had preferential location on the left side large bowel rather than on the right side (p = 0.012), and a higher variation of centromere numbers revealed by fluorescence in situ hybridisation (FISH). To assess the effects of hSgo1 downregulation, hSgo1 knockdown was performed by transfecting the diploid HCT116 cell line with a short hairpin RNA expression vector. hSgo1 knockdown cells proliferated slowly because of both G(2)/M arrest and apoptosis (p<0.001), and markers of CIN in the form of aneuploidy (p<0.001) and micronuclei (p<0.005) were later observed in hSgo1 knockdown cells. Increased centrosome amplification (p<0.05), the presence of binucleated cells and mitotic catastrophes were also noted in hSgo1 knockdown cells.

CONCLUSIONS

These findings suggest that hSgo1-downregulated colorectal cancers have a clinicopathological character of CIN, and hSgo1 downregulation leads to CIN in colorectal cancer cells.

Flavonol Caffeoylglycosides as alpha-Glucosidase Inhibitors from Spiraea cantoniensis Flower

In the screening experiments for rat intestinal alpha-glucosidase inhibitors in 218 plants cultivated in the Japanese temperate region, potent maltase-inhibiting activity was found in the extract of flowers of Spiraea cantoniensis. The enzyme assay guided fractionation of the extract led to the isolation of three flavonol caffeoylglycosides, quercetin 3- O-(6- O-caffeoyl)-beta-galactoside ( 1), kaempferol 3- O-(6- O-caffeoyl)-beta-galactoside ( 2), and kaempferol 3- O-(6- O-caffeoyl)-beta-glucoside ( 3), as rat intestinal maltase inhibitors. This is the first report on the alpha-glucosidase-inhibitory activity of those flavonol caffeoylglycosides. Comparison in the activity of the isolates indicated the importance of caffeoyl substructures in the molecule for the alpha-glucosidase-inhibiting activity. The relatively high contents of the active isolates in the plant suggest that S. cantoniensis could be physiologically useful for treatment of diabetes.

Comparison of the major flavonoid content of S. baicalensis, S. lateriflora, and their commercial products

According to the notification for definition of pharmaceuticals from the Director-General of the Pharmaceutical and Food Safety Bureau, Ministry of Health Labour and Welfare of Japan, the roots of Scutellaria baicalensis (Chinese skullcap) and S. lateriflora (skullcap) are classified as "the raw materials exclusively used as pharmaceuticals", but their aerial parts are classified as "non-pharmaceuticals" so, in principle, there are no health claims for these materials and no descriptions of drug-like dosages or administration directions. Dried root of S. baicalensis is also registered in Japanese Pharmacopoeia XV as scutellaria root. Scutellaria root is considered to have the adverse drug reactions of interstitial pneumonia and drug-induced hepatopathy in kampo medicines (Japanese traditional herbal formulations), and baicalin, its major constituent, is considered to be the cause of the adverse reaction. This study was conducted to evaluate the validity of this borderline between pharmaceuticals and non-pharmaceuticals by analyzing the amounts of four flavonoids, including baicalin, in the roots, stems, and leaves of S. baicalensis and S. lateriflora, and in the commercial products herbal tea and dietary supplements prepared from S. lateriflora. These flavonoids were found in the root of S. baicalensis; its aerial parts, however, did not contain them. On the other hand, the amounts of those flavonoids in the aerial parts of S. lateriflora were larger than in the root. Herbal tea and dietary supplements of S. lateriflora obtained commercially also contained those flavonoids, and the dietary supplements contained amounts of them comparable with that in kampo medicine. These results suggest that classification that the aerial parts of S. lateriflora as non-pharmaceuticals in Japan needs reconsideration.

Effect of MDR1 C3435T polymorphism on cure rates of Helicobacter pylori infection by triple therapy with lansoprazole, amoxicillin and clarithromycin in relation to CYP 2C19 genotypes and 23S rRNA genotypes of H. pylori

BACKGROUND

Polymorphism in MDR1 is associated with variation in the plasma level of a proton pump inhibitor.

AIM

To investigate whether MDR1 polymorphism is associated with eradication rates of Helicobacter pylori by a triple therapy with lansoprazole, amoxicillin and clarithromycin in relation to CYP2C19 genotype status and bacterial susceptibility to clarithromycin.

METHODS

A total of 313 patients infected with H. pylori completed the treatment with lansoprazole 30 mg b.d., clarithromycin 200 mg b.d. and amoxicillin 750 mg b.d. for 1 week. MDR1 C3435T polymorphism and CYP2C19 genotypes of patients and sensitivity of H. pylori to clarithromycin were determined.

RESULTS

Logistic regression analysis revealed that the MDR1 polymorphism as well as CYP2C19 genotypes of patients and clarithromycin-resistance of H. pylori were significantly associated with successful eradication. Eradication rates for H. pylori were 82% (83/101: 95% CI = 73-89), 81% (112/139: CI = 73-87), and 67% (44/73: CI = 48-72) in patients with the MDR1 3435 C/C, C/T and T/T genotype, respectively (P = 0.001).

CONCLUSIONS

Polymorphism of MDR1 is one of the determinants of successful eradication of H. pylori by the triple therapy with lansoprazole, amoxicillin and clarithromycin, together with CYP2C19 genotype and bacterial susceptibility to clarithromycin.

Effect of MDR1 C3435T polymorphism on cure rates of Helicobacter pylori infection by triple therapy with lansoprazole, amoxicillin and clarithromycin in relation to CYP 2C19 genotypes and 23S rRNA genotypes of H. pylori

BACKGROUND

Polymorphism in MDR1 is associated with variation in the plasma level of a proton pump inhibitor.

AIM

To investigate whether MDR1 polymorphism is associated with eradication rates of Helicobacter pylori by a triple therapy with lansoprazole, amoxicillin and clarithromycin in relation to CYP2C19 genotype status and bacterial susceptibility to clarithromycin.

METHODS

A total of 313 patients infected with H. pylori completed the treatment with lansoprazole 30 mg b.d., clarithromycin 200 mg b.d. and amoxicillin 750 mg b.d. for 1 week. MDR1 C3435T polymorphism and CYP2C19 genotypes of patients and sensitivity of H. pylori to clarithromycin were determined.

RESULTS

Logistic regression analysis revealed that the MDR1 polymorphism as well as CYP2C19 genotypes of patients and clarithromycin-resistance of H. pylori were significantly associated with successful eradication. Eradication rates for H. pylori were 82% (83/101: 95% CI = 73-89), 81% (112/139: CI = 73-87), and 67% (44/73: CI = 48-72) in patients with the MDR1 3435 C/C, C/T and T/T genotype, respectively (P = 0.001).

CONCLUSIONS

Polymorphism of MDR1 is one of the determinants of successful eradication of H. pylori by the triple therapy with lansoprazole, amoxicillin and clarithromycin, together with CYP2C19 genotype and bacterial susceptibility to clarithromycin.

Pharmacogenomics-based tailored versus standard therapeutic regimen for eradication of H. pylori

Helicobacter pylori eradication rates by triple therapy with a proton pump inhibitor, amoxicillin, and clarithromycin at standard doses depend on bacterial susceptibility to clarithromycin and patient CYP2C19 genotypes. We examined the usefulness of a personalized therapy for H. pylori infection based on these factors as determined by genetic testing. First, optimal lansoprazole dosing schedules that would achieve sufficient acid inhibition to allow H. pylori eradication therapy in each of different CYP2C19 genotype groups were determined by a 24-h intragastric pH monitoring. Next, 300 H. pylori-positive patients were randomly assigned to the standard regimen group (lansoprazole 30 mg twice daily (b.i.d.)), clarithromycin 400 mg b.i.d., and amoxicillin 750 mg b.i.d. for 1 week) or the tailored regimen group based on CYP2C19 status and bacterial susceptibility to clarithromycin assessed by genetic testing. Patients with failure of eradication underwent the second-line regimen. The per-patient cost required for successful eradication was calculated for each of the groups. In the first-line therapy, the intention-to-treat eradication rate in the tailored regimen group was 96.0% (95% CI=91.5-98.2%, 144/150), significantly higher than that in the standard regimen group (70.0%: 95% CI=62.2-77.2%, 105/150) (P<0.001). Final costs per successful eradication in the tailored and standard regimen groups were $669 and $657, respectively. In conclusion, the pharmacogenomics-based tailored treatment for H. pylori infection allowed a higher eradication rate by the initial treatment without an increase of the final per-patient cost for successful eradication. However, the precise cost-effectiveness of this strategy remains to be determined.

Ubiquitin-dependent degradation of SnoN and Ski is increased in renal fibrosis induced by obstructive injury

Transforming growth factor-beta (TGF-beta) plays a critical role in the progression of renal fibrosis. The activity of TGF-beta is tightly controlled by various mechanisms, among which antagonizing Smad-mediated gene transcription by co-repressors represents one of the important components. We investigated the expression, degradation, and ubiquitination of Smad transcriptional co-repressors SnoN (ski-related novel gene N) and Ski (Sloan-Kettering Institute proto-oncogene) in renal fibrogenesis. We also studied the involvement of Smad-ubiquitination regulatory factor 2 (Smurf2) in ubiquitination of SnoN protein. The kidneys of mice with unilateral ureteral obstruction (UUO) and those of sham-operated mice were used. Renal lesions and the expression of TGF-beta1, type I collagen, SnoN, Ski, and Smurf2 were examined by immunohistochemistry, Western blot, and/or real-time reverse transcriptase-polymerase chain reaction. Degradation and ubiquitination of SnoN/Ski proteins were also investigated. The obstructed kidneys of UUO mice showed progressive tubulointerstitial fibrosis, high expression levels of TGF-beta1, type I collagen, SnoN and Ski mRNAs, and low levels of SnoN and Ski proteins. Both degradation and ubiquitination of SnoN/Ski proteins were markedly increased in the obstructed kidneys, in which Smurf2 expression was increased. Smurf2 immunodepletion in extracts of obstructed kidneys resulted in reduced ubiquitination of SnoN. Our results suggest that the reduction of SnoN/Ski proteins resulting from increased ubiquitin-dependent degradation is involved in the progression of tubulointerstitial fibrosis.

The sequences of the spacer region between the atpF and atpA genes in the plastid genome allows discrimination among three varieties of medicinal Angelica

The dried roots of Angelica acutiloba Kitagawa var. acutiloba Kitagawa, A. acutiloba Kitagawa var. iwatensis Hikino and A. acutiloba Kitagawa var. sugiyamae Hikino have been used as the herbal medicine known in Japan as Japanese Angelica Root. The respective morphological features of, in particular, A. acutiloba var. sugiyamae and A. acutiloba var. iwatensis are similar, and they are not easy to distinguish morphologically from each other. In an attempt to find a method for discriminating among these three varieties, we compared the nucleotide sequence of the spacer region between the atpF and atpA genes among the respective plastid genomes. Comparison of these sequences allowed us to identify each of the three varieties unequivocally.

Screening of indigenous plants from Japan for modulating effects on transformation of the aryl hydrocarbon receptor

The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor with which halogenated and polycyclic aromatic hydrocarbons such as dioxins and benzo[a]pyrene interact as ligands. Since such compounds cause various toxicological effects, including cancer, through the transformation of AhR, it is important to determine influence of modulating factors. It has been reported that certain plant components such as flavonoids and indoles can affect AhR transformation. In this study, to obtain clues to novel ligands of AhR, 191 species of indigenous plants were collected in Japan, and their 50% methanolic extracts (total 368 plant parts) were tested for modulating effects on AhR transformation in a cell-free system using a rat hepatic cytosolic fraction. Among tested extracts at a concentration of 1 mg dry weight of plant/mL, 174 of 368 extracts suppressed 1 nM 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced AhR transformation to 50% or less, while 9 extracts per se induced AhR transformation equivalent to more than 20% of that induced by 1 nM TCDD. Mallotus japonicus (Thunb.) Muell. (leaf) and Trichosanthes rostrata Kitamura (fruit and fruit skin) strongly suppressed 1 nM TCDD-induced AhR transformation, while Phellodendron amurense Ruprecht (seed) per se strongly induced AhR transformation. These results suggest that a large variety of plants in Japan contain various compounds modulating, mainly suppressing, AhR transformation.

Poor metabolizer genotype status of CYP2C19 is a risk factor for developing gastric cancer in Japanese patients with Helicobacter pylori infection

BACKGROUND

Cytochrome P450 2C19 (CYP2C19) polymorphism has been associated with the development of lung, liver or oesophageal cancer by detoxification of carcinogen(s) or activation of procarcinogen(s).

AIM

To clarify the association between CYP2C19 polymorphisms and gastric cancer development in Japanese. Methods : We determined CYP2C19 genotypes (CYP2C19*1, *2 and *3) in 111 Helicobacter pylori-positive patients with gastric cancer and 315 H. pylori-positive controls without gastric cancer consisting of patients with gastritis only or peptic ulcer. Frequencies of CYP2C19 genotypes and serum pepsinogen I and II levels, a biomarker of gastric atrophy, in the gastric cancers and controls were compared.

RESULTS

Frequencies of homozygous extensive metabolizers, heterozygous extensive metabolizers and poor metabolizers were 31.5%, 42.3% and 26.2% in the gastric cancers and 38.1%, 47.0% and 14.9% in the controls, respectively (P = 0.046). Poor metabolizers were associated with an increased risk for developing gastric cancer with the age- and sex-adjusted odds ratio (OR) of 1.975 [95% confidence interval (CI): 1.068-3.649], especially for diffuse type (OR: 3.385, CI: 1.187-9.648). There is no significant association between CYP2C19 genotypes and serum pepsinogen I level or pepsinogen I/II ratios, although serum pepsinogen I level in gastric cancers were significantly decreased.

CONCLUSIONS

In H. pylori-positive Japanese, poor metabolizers of CYP2C19 appear to be at an increased risk for developing gastric cancer, especially diffuse type, and may require an intensive follow-up for scrutinizing possible gastric cancer development.

Effect of concomitant dosing of famotidine with lansoprazole on gastric acid secretion in relation to CYP2C19 genotype status

BACKGROUND

Famotidine increases Helicobacter pylori-eradication rates by a triple lansoprazole/amoxicillin/clarithromycin therapy in patients with the rapid extensive metabolizer genotype of CYP2C19.

AIM

To determine the effect of famotidine on the gastric acid inhibition by lansoprazole in relation to CYP2C19 genotypes.

METHODS

Twenty healthy volunteers with different CYP2C19 genotypes--consisting of six rapid extensive metabolizers, nine intermediate metabolizers and five poor metabolizers--underwent three 7-day courses with placebo, lansoprazole 30 mg twice daily, and lansoprazole 30 mg twice plus famotidine 20 mg twice daily. Lansoprazole was dosed after breakfast and dinner. Famotidine was dosed after lunch and at bedtime. Intragastric pH monitoring was performed for 24 h on day 7 of each course.

RESULTS

With placebo, no difference was observed in intragastric pH profiles among the three CYP2C19 genotype groups. With lansoprazole 30 mg twice daily, the median of 24-h intragastric pH in poor metabolizers (6.1) was significantly higher than those of rapid extensive metabolizers (4.5) and intermediate metabolizers (5.0), respectively (P = 0.0176 and 0.0388), whereas with lansoprazole 30 mg twice and famotidine 20 mg twice daily, the medians were 5.4, 5.7, and 6.1, respectively (not significant).

CONCLUSION

Acid inhibition by lansoprazole was influenced by CYP2C19 genotype status. This influence was offset by the concomitant use of famotidine.

The sequences of the plastid gene rpl16 and the rpl16-rpl14 spacer region allow discrimination among six species of Scutellaria

Dried aerial parts of Scutellaria galericulata L. (Labiatae; marsh skullcap) and Scutellaria lateriflora L. (Labiatae; mad dog skullcap) are mainly used as skullcap, a medicinal herb, in Europe and the United States. The respective dried aerial parts of the two species are difficult to distinguish morphologically from each other. We attempted to discriminate among six species (Scutellaria altissima L. (Labiatae), Scutellaria baicalensis Georgi (Labiatae), Scutellaria galericulata, Scutellaria incana Spreng. (Labiatae), Scutellaria indica L. (Labiatae) and Scutellaria lateriflora) of Scutellaria, which include three medicinal species (Scutellaria galericulata, Scutellaria lateriflora and Scutellaria baicalensis), by comparing the respective nucleotide sequences of the plastid rpl16 gene and the rpl16-rpl14 spacer region. Comparisons of these sequences allowed us to identify each of the six species unequivocally.

High ratio of 1,25-dihydroxyvitamin D3 to parathyroid hormone in serum of tuberculous patients with end-stage renal disease

AIM

Diagnosis of tuberculosis is sometimes difficult because of the low specificity of diagnostic procedures especially in patients on end-stage renal disease (ESRD). As abnormal vitamin D metabolism has been reported in tuberculosis, the aim of the present study was to determine whether serum concentration of 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) may be a useful diagnostic indicator of tuberculosis in patients with ESRD.

PATIENTS AND METHODS

Serum concentrations of 1,25-(OH)2D3, parathyroid hormone (PTH), and calcium were compared in 6 patients with ESRD and active tuberculosis (ESRD-TB group) and 110 patients with ESRD and no tuberculosis (ESRD group). These parameters were compared before and after treatment for tuberculosis in patients of ESRD-TB group.

RESULTS

Hypercalcemia was observed in all 6 patients in the ESRD-TB group. Both higher serum concentration of 1,25-(OH)2D3 and lower serum concentration of PTH were observed in the ESRD-TB group relative to the ESRD group, suggesting enhanced extrarenal production of 1,25-(OH)2D3 and suppressed secretion of PTH by hypercalcemia in the ESRD-TB group. However, these parameters could not be used to distinguish the ESRD-TB group from the ESRD group. The ratio of 1,25-(OH)2D3 to PTH in serum was above 0.9 in the ESRD-TB group and below 0.9 in the ESRD group. Antituberculous treatment reduced this ratio to the range observed in the ESRD group.

CONCLUSION

High ratio of 1,25-(OH)2D3 to PTH in serum is noted in active tuberculous patients with ESRD because of enhanced extrarenal production of 1,25-(OH)2D3.

A case of anaphylactoid shock induced by the BS polysulfone hemodialyzer but not by the F8-HPS polysulfone hemodialyzer

A 57-year-old woman was admitted because of severe bradycardia and hypotension caused by an anti-arrhythmic agent and beta-blocker. For 19 months before admission, she had been undergoing hemodialysis with an F8-HPS polysulfone membrane hemodialyzer without any complications. In 2 dialysis sessions after admission, when a BS polysulfone membrane was used, she experienced anaphylactoid shock with severe hypotension leading to syncope, dyspnea and vomiting, just after the start of hemodialysis. After the anaphylactoid shock, her dialyzer membrane was changed to a cellulose triacetate membrane and she did not suffer from such attacks. This case indicates that severe anaphylactoid shock may be caused by a biocompatible dialyzer membrane and that the reactions of patients to each polysulfone membrane may differ among polysulfone membranes made by different manufacturers.

Discrimination among species of Papaver based on the plastid rpl16 gene and the rpl16-rpl14 spacer sequence

An attempt was made to discriminate among six species of Papaver (P. bracteatum, P. orientale, P. pseudo-orientale, P. rhoeas, P. setigerum and P. somniferum) by comparing the nucleotide sequences of the plastid rpl16 gene and the rpl16-rpl14 spacer region. Comparison of sequences allowed us to distinguish five species, namely P. bracteatum, P. orientale, P. pseudo-orientale, P. rhoeas and P. setigerum plus P. somniferum from one another, but sequences from P. setigerum and P. somniferum were identical. It is difficult to distinguish between P. bracteatum, P. orientale and P. pseudo-orientale at the vegetative stage of growth. However, our method allowed us to distinguish between these three species and the others using nucleotide sequences and should allow identification of P. bracteatum that has been cultivated illegally in the garden in Japan. Furthermore, P. rhoeas was clearly discriminated from P. setigerum and P. somniferum by reference to the sequence of the rpl16 exon using young seedlings.

Association between blood indoxyl sulfate and carbonyl stress marker in hemodialysis patients

BACKGROUND

Indoxyl sulfate (IS) is a protein-bound solute, which is progressively retained in blood according to the decline of renal function. However, clinical relevance of excess IS in hemodialysis (HD) patients remains unknown.

PATIENTS AND METHODS

We measured serum IS and clinical parameters including pentosidine, carboxymethyllysine (CML) and homocysteine levels in 55 HD patients (age: 67 +/- 2 years, time on HD: 67 +/- 11 months, male/female = 30/25), and examined the relationship between IS and these data.

RESULTS

Serum IS was markedly increased in HD patients (80.49 +/- 6.17 microg/ml) compared to normal range (< 1.9 microg/ml). IS was significantly and positively correlated with time on HD (p < 0.01), blood urea nitrogen (p < 0.01), beta2-microglobulin (p < 0.03), and protein catabolic rate (PCR) (p < 0.01). The patients with increased IS needed a higher erythropoietin dosage. Blood IS was positively correlated with pentosidine (r = 0.505, p < 0.01) and CML (r = 0.275, p < 0.05). In contrast, blood IS was not associated with nutritional and inflammatory parameters. A stepwise multiple regression analysis revealed that time on HD, PCR and pentosidine were significant determinants of IS.

CONCLUSIONS

Serum IS was related to time on HD and dietary protein intake. Accumulated IS may be associated with enhanced carbonyl stress in chronic HD patients.

Pseudohyperkalemia occurring in a patient with chronic renal failure and polycythemia vera without severe leukocytosis or thrombocytosis

Pseudohyperkalemia is defined as a serum potassium concentration 0.4 mEq/l greater than the plasma concentration. The basis of this phenomenon is the release of intracellular potassium from platelets, leukocytes, or erythrocytes, commonly in the setting of extreme leukocytosis (> 10 x 10(4)/microl) or thrombocytosis (> 60 x 10(4)/microl). We report a case of pseudohyperkalemia in a patient with chronic renal failure and polycythemia vera without the finding of severe leukocytosis or thrombocytosis (white blood cell count 1.88 x 10(4)/microl and platelet count 37.9 x 10(4)/microl, respectively). The serum potassium concentration was 8.2 mEq/l, while the plasma potassium level was 6.4 mEq/l in a sample obtained simultaneously. The concentrations of platelet factor IV and beta-thromboglobulin, known to be markers of platelet activation, were greater than 100 ng/ml and 200 ng/ml, respectively, indicating that platelet activation may have been related to the development of pseudohyperkalemia in this patient. These findings suggest that pseudohyperkalemia should be considered when hyperkalemia is seen in a patient with chronic renal failure and myeloproliferative disorders.

Measurement of des-gamma-carboxy prothrombin levels in hemodialysis patients positive for anti-hepatitis virus C antibody

BACKGROUND

The prevalence of anti-hepatitis virus C (HCV) antibody is much higher in hemodialysis (HD) patients than in the normal population. Recently, blood des-gamma-carboxy prothrombin (PIVKA-II) has been demonstrated as a sensitive marker for the early detection of hepatocellular carcinoma (HCC). In this study, we measured blood PIVKA-II in HD patients positive for anti-HCV antibody or hepatitis B virus surface (HBs) antigen to examine if HD therapy may affect the measurement of PIVKA-II.

PATIENTS AND METHODS

Ninety-four stable HD patients who had anti-HCV antibodies (n = 86) or HBs antigen (n = 8) without any evidence of HCC were enrolled in the study (age: 60 +/- 11 years, duration of HD: 17 +/- 10 years, male/female = 63/31). Five patients had liver cirrhosis and another 5 patients received warfarin treatment. We simultaneously measured serum PIVKA-II and alpha-fetoprotein (AFP), and compared the association between these markers and HCV RNA titer and laboratory parameters.

RESULTS

Serum PIVKA-II became positive (> or = 40 mAU/ml) in only 5.6% (5/89) of patients without warfarin administration, ranging from 47 to 71 mAU/ml. Seventy out of 89 patients (78.7%) were below 20 mAU/ml. Serum PIVKA-II did not correlate with biochemical parameters including HCV RNA, while serum AFP was significantly correlated with serum AST (r = 0.21, p < 0.05), gamma-GTP (r = 0.21, p < 0.01) and platelet counts (r = -0.29, p < 0.01), respectively. In contrast, 5 patients receiving warfarin had an extremely high PIVKA-II value ranging from 1,930 to 19,900 mAU/ml. PIVKA-II was significantly and inversely correlated with the thrombotest value (r = -0.72, p = 0.01).

CONCLUSION

The positivity of blood PIVKA-II in HD patients with hepatitis viremia was identical to that in patients without renal failure. Warfarin treatment dramatically increased serum PIVKA-II more than 1,000 mAU/ml. These findings suggested that HD treatment itself did not affect the measurement of PIVKA-II, but vitamin K deficiency can readily influence the PIVKA-II level in dialysis patients.

Focal segmental glomerulosclerosis in a case of panhypopituitarism: a possible role of growth hormone treatment

Panhypopituitarism manifests various symptoms including growth failure, hypothyroidism, adrenal insufficiency and hypogonadism. Dwarfism is an important problem in children with this condition, and long-term treatment with recombinant human growth hormone (GH) is usually required. We report a 24-year-old man with panhypopituitarism complicated by focal segmental glomerulosclerosis (FSGS). The patient had been treated with GH for hypopituitary dwarfism from 3 years of age. Proteinuria was initially noticed at 15 years of age and persisted despite cessation of GH supplementation at 18 years of age. A renal biopsy specimen showed glomerular hypertrophy and limited glomerulosclerosis, compatible with FSGS. To our knowledge, this is the first reported case of panhypopituitarism complicated by FSGS. Our case suggests that GH treatment for dwarfism may induce irreversible glomerular disease.

Ultrasound changes of the carpal tunnel in patients receiving long-term hemodialysis: a cross-sectional and longitudinal study

BACKGROUND

Carpal tunnel syndrome (CTS) is one of the major problems of long-term hemodialysis (HD), but sometimes difficult to distinguish from uremic or diabetic neuropathy by clinical symptoms.

PATIENTS AND METHODS

To evaluate the diagnosis of CTS more precisely, we examined the ultrasonographic alterations of the carpal tunnel and tendons of 90 wrists from 45 patients undergoing HD for more than 5 years. We measured the thickness of the palmar radiocarpal ligament (PRL), corresponding to the posterior wall of the carpal tunnel (CT), and the width of the CT, and compared those values with sensory (SCV), motor conduction velocity (MCV) of the median nerve and clinical symptoms. In addition, we longitudinally measured CT and PRL in the same patients for 5 years, and compared ultrasonographic changes and clinical parameters.

RESULTS

A linear positive relationship was found between HD duration and PRL thickness (r = 0.43, p < 0.01) or CT width (r = 0.53, p < 0.01). CT diameter was negatively correlated with MCV (r = -0.30, p < 0.01) and SCV (r = -0.33, p < 0.04). PRL thickness was also inversely correlated with MCV (r = -0.44, p < 0.01) and SCV (r = -0.46, p < 0.01) of the median nerve, respectively. The wrists with clinical CTS and/or previous CTS surgery had significantly greater CT and PRL values compared to patients without CTS (CT: 6.1 0.2vs. 8.0+/-0.3 mm,p<0.01;PRL: 1.9+/-0.1 vs. 3.6 +/- 0.2 mm, p < 0.01). There was a significant increase in CT width from 6.2 +/- 0.2 to 7.1 +/- 0.2 mm (p < 0.01) and PRL thickness from 2.4 +/- 0.2 to 2.8 +/- 0.2 mm (p <0.01) during the 5-year observation, respectively. PRL thickness was constantly increased at the rate of 0.4 mm during the study. However, no significant association was found between the 5-year increases in CT and PRL distance and age, gender, the prevalence of diabetes, or laboratory parameters such as blood beta2-microglobulin, pentosidine and Kt/V(urea).

CONCLUSION

Our data suggest that echographic evaluation of the wrist tissue thickness was useful to assess the progression of CTS. Serial measurements of the wrist by echography may be helpful to clarify the advance of subclinical CTS in patients receiving long-term HD.

Tuberculous arthritis mimicking neoplasm in a hemodialysis patient

Hemodialysis patients are known to develop the complication of extrapulmonary tuberculosis more frequently than the general population. Tuberculous arthritis is a rare form of extrapulmonary tuberculosis and is reported to occur in approximately 1% of cases in nonuremic patients. Only 3 cases in dialysis patients, who were not proven by a bacterial culture or had died before treatment, have been reported. We report herein a culture-proven case of tuberculous arthritis developing at the sternoclavicular joint, which initially mimicked an apparent neoplasm in a hemodialysis patient. A favorable outcome was obtained after antituberculous therapy. Tuberculosis must be considered one of the most significant diagnoses in hemodialysis patients who present with a tumor-like lesion.

Association between circulating leptin and soluble receptors for tumor necrosis factor-alpha in hemodialysis patients

BACKGROUND

The expression of leptin, an adipocyte-derived protein, is regulated by tumor necrosis factor-alpha (TNF-alpha). Since circulating leptin levels adjusted for body fat mass are reported to be increased in dialysis patients, we examined if the TNF-alpha system may influence blood leptin levels in hemodialysis (HD) patients.

PATIENTS AND METHODS

Sixty-three stable HD patients who had no signs of infection, collagen disease or malignancy were enrolled in the study (age: 63 +/- 1 years, duration of HD: 14 +/- 1 years, male/female = 34/29). We measured serum leptin, TNF-alpha, soluble receptors for TNF-alpha (sTNFR p55, p80) and interleukin-6 (IL-6) concentrations with ELISA kits. Body fat mass was determined using DEXA. To evaluate the potential association between serum leptin and the TNF-alpha system, we compared serum leptin and sTNFR levels, which has been validated as a sensitive marker of activation of the TNF-alpha system.

RESULTS

Serum leptin levels were significantly higher in female patients compared to male patients (14.07 +/- 3.60 vs. 4.26 +/- 0.85 ng/ml, p < 0.005). A strong correlation was found between serum leptin levels and estimated body fat mass both in males (r = 0.742, p < 0.0001) and females (r = 0.769, p < 0.001), respectively. Serum TNF-alpha, sTNFR p55, p80 and IL-6 levels were significantly increased in HD patients compared to normal subjects. However, no association was found between serum leptin and serum TNF-alpha, sTNFR p55, p80 and IL-6 levels. Serum leptin levels were significantly correlated with the atherosclerotic index both in men (r = 0.382, p = 0.027) and women (r = 0.281, p = 0.041). In contrast, there was no relationship between circulating leptin values and serum albumin, transferrin, creatinine levels, or normalized protein catabolic rate in each sex.

CONCLUSION

These findings suggested that serum leptin is independent of the TNF-alpha system, and is mainly correlated with body fat volume in HD patients. Elevation of circulating leptin may be associated with the disturbance of the serum lipid profile rather than malnutrition in patients receiving long-term HD.

Dominant effect of supplemented-sucrose on the low protein diet-induced increase in blood pressure of Sprague-Dawley rats

A low-protein diet (LPD) is known to affect the regulation of hemodynamics, and could contribute to the genesis of hypertension. We investigated the mechanism for the LPD-induced elevation of blood pressure in 52 Sprague-Dawley rats. Rats fed the LPD for 8 weeks showed a significantly higher blood pressure than those fed on a normal-protein diet (NPD) when the LPD included sucrose as a predominant component of carbohydrate (LPD with a high sucrose content, 135 +/- 2 mmHg; NPD, 124 +/- 2 mmHg; p<0.05). However, LPD with a low sucrose content, in which corn starch was the main component of carbohydrate, did not have a hypertensive effect (125 +/- 2 mmHg). Urinary epinephrine and norepinephrine excretion was significantly higher in the LPD high-sucrose group than in the NPD and LPD low-sucrose groups, and there was a significant positive correlation between urinary norepinephrine excretion and systolic blood pressure. Urinary nitric oxide excretion was no different between these groups, and 2 % L-arginine administration exerted no antihypertensive effect on the LPD-induced elevation of blood pressure. Sodium restriction also did not attenuate the LPD-induced elevation of blood pressure. These results suggest that the effect of LPD on blood pressure could be interpreted as the effect of the high sucrose content supplemented to the LPD rather than the direct effect of protein restriction, and that the stimulation of sympathetic nervous activity was associated with this elevation of blood pressure.

Dexamethasone attenuates neutrophil infiltration in the rat kidney in ischemia/reperfusion injury: the possible role of nitroxyl

Neutrophil infiltration to the tissue, which is one of the important pathogenetic factors in ischemia/reperfusion injury, can be inhibited by glucocorticoids. The purpose of the present study was to clarify the mechanisms by which glucocorticoids inhibit neutrophil infiltration in renal ischemia/reperfusion injury in rats. Pretreatment with dexamethasone significantly attenuated the enhanced neutrophil infiltration and expression of intercellular adhesion molecule-1 induced by renal ischemia/reperfusion. Treatment with nitroxyl anion releaser known as Angeli's salt abolished the beneficial effect of dexamethasone in renal ischemia/reperfusion. Renal dysfunction and tubular damage induced by renal ischemia/reperfusion were not ameliorated by pretreatment with dexamthasone. These results indicate that the attenuation by dexamethasone of neutrophil infiltration and intercellular adhesion molecule-1 expression during renal ischemia/reperfusion may be mediated by the suppressed production of nitroxyl anion. Thus, neutrophil infiltration in renal ischemia/reperfusion injury may be mediated, at least in part, by the enhanced production of nitroxyl anion.

Elevation of blood (1-->3)-beta-D-glucan concentrations in hemodialysis patients

Determination of the blood (1-->3)-beta-D-glucan (beta-DG) concentration is a sensitive marker to detect the presence of deep mycosis and fungal infections. Although cellulose material is known to contain beta-DG, the influence of a cellulose dialyzer membrane on the blood beta-DG level remains to be elucidated. In this study, we determined the plasma beta-DG levels in dialysis outpatients using either a modified regenerated cellulose (MRC) or a synthetic polysulfone (PS) membrane for more than 3 months. Plasma beta-DG levels were extremely high in patients using the MRC (2,778 +/- 549 pg/ml, n = 9) but not the PS membrane (18.8 +/- 3.7 pg/ml, n = 8) compared to normal ranges (<20 pg/ml). A single dialysis session using the MRC membrane further increased blood beta-DG values to 5,561 +/- 722 pg/ml (p < 0.01). After changing the membranes from MRC to PS, the blood beta-DG levels gradually decreased and reached 29.6 +/- 6.0 pg/ml at 6 months. In contrast, the PS membrane did not affect plasma beta-DG levels after a single dialysis session (16.0 +/- 3.9 pg/ml) or 4 months later (24.0 +/- 4.9 pg/ml). These findings suggested that a cellulose membrane could influence the measurement of blood beta-DG concentrations in the long-term. Careful assessment is required to diagnose the presence of fungal infection in HD patients using a cellulose membrane.

Psoas abscess with osteomyelitis in a patient undergoing long-term hemodialysis

We describe a 69-year-old male patient on maintenance hemodialysis for 24 years who developed a fatal left psoas abscess with osteomyelitis at the hip joint following acute enterocolitis. He had systemic beta(2)-microglobulin amyloid deposition in colon epithelium and psoas muscle. Cultures from abscess fluid and femoral bone marrow yielded Bacteroides fragilis. To our knowledge, this is the first case on hemodialysis having a psoas abscess following acute gastrointestinal infection. This rare case suggested that a secondary psoas abscess could be one of the occult infections in patients undergoing long-term maintenance hemodialysis.

High blood soluble receptor p80 for tumour necrosis factor-alpha is associated with erythropoietin resistance in haemodialysis patients

BACKGROUND

Inflammation is one of the major causes of resistance to erythropoietin (rHuEpo) treatment. Tumour necrosis factor-alpha (TNF-alpha), one of the most potent proinflammatory cytokines, is known to inhibit human erythropoiesis directly in vitro. Although blood levels of soluble receptors for TNF-alpha (sTNFRs) are elevated in haemodialysis (HD) patients, the role of sTNFR for rHuEpo responsiveness in HD patients remains to be clarified.

METHODS

We measured serum sTNFR (p55 and p80) levels in 83 stable outpatients undergoing regular HD (age 62+/-1, HD duration 15+/-1 years). After dividing the patients into three groups according to rHuEpo dose: (low (L) <60, n=31; moderate (M) > or =60 to <120, n=31; high (H) > or =120 U/kg/week rHuEpo, n=21), we examined the relationship between serum sTNFR levels and the degree of renal anaemia and rHuEpo dosage.

RESULTS

Haemoglobin was significantly higher in patients receiving low rHuEpo dosage (L, 10.5+/-0.2; M, 9.7+/-0.1; H, 9.5+/-0.2 g/dl, P<0.01 vs M and H groups). There were no differences in blood TNF-alpha, sTNFR p55, C-reactive protein, albumin, ferritin, or intact parathyroid hormone levels among the three groups. Body mass index and creatinine generation rate, a marker of whole-body muscle volume, were significantly reduced in group H (P<0.01). Serum sTNFR p80 levels were significantly higher in group H (4.88+/-0.45 ng/ml) than in L (3.73+/-0.14 ng/ml) and M (3.67+/-0.21 ng/ml) groups (P<0.05). The blood interleukin (IL)-6 level was also increased in patients requiring high rHuEpo doses (L, 5.5+/-0.5; M, 6.4+/-0.5; H, 10.2+/-2.0 pg/ml, P<0.05 vs L and H groups). A stepwise regression analysis revealed that gender and sTNFR p80 were significant predictors of rHuEpo dosage. A significant direct relationship was found between rHuEpo dose and sTNFR p80 (r=0.499) and IL-6 (r=0.439) values in women (P<0.01) but not in men.

CONCLUSIONS

These findings suggest that high blood sTNFR p80 may contribute to the development of rHuEpo resistance in female patients undergoing long-term HD.