[Stress response genes expression analysis of barley Hordeum vulgare under space flight environment]

Transcriptome of barley Hordeum vulgare grown aboard International Space Station (ISS) was analyzed by means of microarray. It was revealed 500 genes with mRNA level, changed more than two folds in space environment. Among them are genes encoding stress response proteins, videlicet Heat Shock Proteins (HSP), Pathogenesis-Related Proteins (PR) and Antioxidant Proteins. Further analysis of these genes by real time PCR showed enhanced transcription level of Reactive oxygen Species (ROS) scavenging genes. The mRNA level of superoxide dismutase (sod) was 6 folds higher in space environment when compare to Earth conditions. Glutamyl transferase gene expression was enhanced 24 times in space. Transcription of catalase gene (cat) was increased 18 times and of ascorbate peroxidase was increased 3 times in space in comparison with ground control. For the first time it was shown that space flight environment may induce oxidative stress in plants.

[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.

Intrinsic Radiosensitivity and PLD Repair in Osteosarcoma Cell Lines

The response to radiation of seven osteosarcoma cell lines was analysed by in vitro colony-forming assay and compared with that of eight human fibroblast strains. The values of D0, the surviving fraction after 2 Gy (S2Gy), and the mean inactivation dose (D) of osteosarcoma cells in log-phase culture were significantly higher than those of fibroblast strains (p less than 0.01). PLD (potentially lethal damage) repair of osteosarcoma cells evaluated in the plateau phase of growth showed great variation for enhancement of survival, although all of the values were maximized within 12 h after irradiation. In the osteosarcoma, intrinsic radiosensitivity in vitro reflected the clinical response to radiation. However, the capacity for PLD repair might not be a good indicator for predicting the results of radiation therapy.

The association of vacA genotype and Helicobacter pylori-related disease in Latin American and African populations

In the populations of Western countries, particular genotypes of the vacuolating cytotoxin gene, vacA (vacA s, signal region variants; vacA m, middle region variants) of Helicobacter pylori are believed to be risk factors for the development of peptic ulcers and gastric cancer. However, it was unclear whether these vacA gene variants are associated with the development of gastrointestinal diseases in developing nations. The relationship between vacA genotypes and H. pylori-related disease development in Latin American and African populations was investigated using meta-analysis of 2612 patients from Latin America (2285 strains) and 520 patients from Africa (434 strains). The frequencies of vacA s and m genotypes differed between strains from Latin America (77.2% for s1 and 68.1% for m1) and Africa (83.9% for s1 and 56.7% for m1). Latin American strains with s1 and m1 genotypes increased the risk of gastric cancer (OR 4.17, 95% CI 2.49-6.98 for s1, and 3.59, 2.27-5.68 for m1) and peptic ulcers (e.g. 1.73, 1.37-2.20 for s1). African strains with the s1 or m1 genotypes also increased the risk of peptic ulcers (8.69, 1.16-64.75 for s1) and gastric cancer (10.18, 2.36-43.84 for m1). The cagA-positive genotype frequently coincided with s1 and m1 genotypes in both populations. Overall, the vacA s and m genotypes were related to gastric cancer and peptic ulcer development and might be useful markers of risk factors for gastrointestinal disease, especially in Latin America. Further studies will be required to evaluate the effects of vacA genotypes in African populations because of the small sample number currently available.

88 EXPRESSION OF ENZYMES RELATED TO HOMOCYSTEINE METABOLISM AND HOMOCYSTEINE SENSITIVITY IN BOVINE PREIMPLANTATION EMBRYOS

Homocysteine is a nonessential amino acid produced through methionine metabolism. Elevation of homocysteine levels (hyperhomocysteinemia) increases intracellular S-adenosylhomocysteine (SAH). S-adenosylhomocysteine binds to methyltransferases (MT) with greater affinity than does S-adenosylmethionine, which is the universal methyl donor used by various cellular MT, including DNA and histone MT. Thus, SAH acts as a potent competitive inhibitor of methylation reactions. Therefore, disorder of homocysteine metabolism may affect cellular homeostasis in part through the process involving methylation reactions (Williams KT and Schalinske KL 2007 J. Nutr. 137, 311–314). Despite its predicted importance, the involvement of homocysteine metabolism in pre-implantation embryonic development remains unaddressed. In the present study, the expression of enzymes related to homocysteine metabolism in bovine pre-implantation embryos and the effects of homocysteine on the post-fertilization development of these embryos in vitro were investigated. Cumulus-enclosed oocytes obtained from slaughterhouse bovine ovaries were in vitro-matured (IVM) for 22 h in modified synthetic oviduct fluid (mSOF) supplemented with 10% v/v FCS and 0.2 IU mL–1 follicle-stimulating hormone. After IVM, the oocytes were subjected to IVF with Percoll gradient-selected sperm from one bull in an mSOF-based medium for 20 h. After IVF, presumptive zygotes were freed from the cumulus cells and cultured in mSOF up to Day 8 (IVF = Day 0). All cultures were performed at 38.5°C under 5% CO2, 5% O2, and 90% N2. Total RNA was extracted from individual blastocysts on Day 7 to 8 and reverse transcribed to cDNA using oligo(dT) primer. Transcripts for methionine adenosyltransferase 2A (MAT2A), MAT2B, adenosylhomocysteinase, methionine synthase, betaine-homocysteine MT, serine hydroxymethyltransferase 1, and 5,10-methylenetetrahydrofolate reductase were examined by qualitative PCR using bovine-specific primers for each gene and the cDNA as templates. β-Actin transcripts were used as an internal control. Moreover, presumptive zygotes after IVF were cultured in mSOF supplemented with 0 (control), 10, and 100 μm homocysteine, and development to cleavage stage and blastocyst was assessed on Day 3 and Day 7 and 8, respectively. The cultures were replicated 4 times using 561 embryos. The development data were statistically analyzed by using the general linear model. Transcripts for all genes examined were detected. Homocysteine added to the culture medium of bovine IVF embryos did not affect the cleavage rate (86.8, 83.3, and 84.3% for control, 10 μm, and 100 μm, respectively); however, blastocyst rate significantly decreased (P = 0.02) on Day 7 (12.8, 9.3, and 7.5%, respectively). The blastocyst rate on Day 8 showed no difference (P = 0.33) among the groups (24.4, 20.4, and 20.1%, respectively). These results indicate that a system for homocysteine metabolism is present in bovine pre-implantation embryos and that high homocysteine levels affect the developmental kinetics of these embryos. Supported by KAKENHI.

Endocervical adenocarcinoma associated with lobular endocervical glandular hyperplasia showing rapid reaccumulation of hydrometra

Mucinous endocervical adenocarcinoma is characterized by increased watery vaginal discharge, but the early diagnosis is sometimes difficult because biopsy specimen might only serve to sample a superficial part of the tumor. The patient presented with complaints of abdominal distention. No vaginal bleeding or watery discharge was observed. Hydrometra was suspected by imaging studies. Rapid reaccumulation of hydrometra was seen despite drainage. Papanicolaou smear of endocervix and endometrium followed by fractional curettage was performed, but failed to confirm the diagnosis. To investigate the unknown origin of hydrometra, an exploratory laparotomy with total hysterectomy and bilateral salpingo-oophorectomy was performed, followed by pelvic lymphadenectomy because biopsy specimens during operation suggested adenocarcinoma of the cervix. The final pathologic study of surgical specimens revealed mucinous adenocarcinoma, which was located on the proximal area of cervix. Adjacent to carcinoma tissue, lobular endocervical glandular hyperplasia (LEGH) was detected. Pyloric gland mucin (HIK1083), MUC6, and MUC5AC were diffusely immunopositive in the cytoplasm of LEGH cells and the immunoreactivity became weaker in adenocarcinoma cells with tumor progression and loss of differentiation. Based on histopathologic features of the present case, there seems to be a possible link between LEGH and conventional mucinous endocervical adenocarcinomas. The physician should keep in mind the possible existence of endocervical adenocarcinoma in a patient showing rapid reaccumulation of hydrometra, when uterine malignancies are clinically suspected and biopsy finding fails to confirm the diagnosis.

Association study between catechol-O-methyltransferase polymorphisms and uterine leiomyomas in a Japanese population

PURPOSE

To investigate a possible association between uterine leiomyomas and catechol-O-methyltransferase (COMT) polymorphisms in a Japanese population.

METHODS

We compared the allele frequencies and genotype distributions of the exon 4 NlaIII restriction site polymorphism (RSP), the P2 promoter HindIII RSP at -1217, and the exon 6 BglI RSP in the COMT gene in 250 leiomyoma cases and 182 controls using polymerase chain reaction-restriction fragment-length polymorphism analysis.

RESULTS

No significant differences in allele frequencies and genotype distributions of the exon 4 NlaIII RSP, the P2 promoter HindIII RSP at -1217, and the exon 6 BglI RSP were found between uterine leiomyoma cases and controls. Moreover, no associations were noted between these three polymorphisms in COMT genes and leiomyoma size or a family history of uterine leiomyomas.

CONCLUSION

COMT gene polymorphisms are unlikely to be associated with an increased risk of uterine leiomyomas in a Japanese population.

Chondrogenic potential of human synovial mesenchymal stem cells in alginate

OBJECTIVE

In a recent study, we demonstrated that mesenchymal stem cells (MSCs) derived from the synovial membranes of bovine shoulder joints could differentiate into chondrocytes when cultured in alginate. The purpose of the present study was to establish the conditions under which synovial MSCs derived from aging human donors can be induced to undergo chondrogenic differentiation using the same alginate system.

METHODS

MSCs were obtained by digesting the knee-joint synovial membranes of osteoarthritic human donors (aged 59-76 years), and expanded in monolayer cultures. The cells were then seeded at a numerical density of 4x10(6)/ml within discs of 2% alginate, which were cultured in serum-containing or serum-free medium (the latter being supplemented with 1% insulin, transferrin, selenium (ITS). The chondrogenic differentiation capacity of the cells was tested by exposing them to the morphogens transforming growth factor-beta1 (TGF-beta1), TGF-beta2, TGF-beta3, insulin-like growth factor-1 (IGF-1), bone morphogenetic protein-2 (BMP-2) and BMP-7, as well as to the synthetic glucocorticoid dexamethasone. The relative mRNA levels of collagen types I and II, of aggrecan and of Sox9 were determined quantitatively by the real-time polymerase chain reaction (PCR). The extracellular deposition of proteoglycans was evaluated histologically after staining with Toluidine Blue, and that of type-II collagen by immunohistochemistry.

RESULTS

BMP-2 induced the chondrogenic differentiation of human synovial MSCs in a dose-dependent manner. The response elicited by BMP-7 was comparable. Both of these agents were more potent than TGF-beta1. A higher level of BMP-2-induced chondrogenic differentiation was achieved in the absence than in the presence of serum. In the presence of dexamethasone, the BMP-2-induced expression of mRNAs for aggrecan and type-II collagen was suppressed; the weaker TGF-beta1-induced expression of these chondrogenic markers was not obviously affected.

CONCLUSIONS

We have demonstrated that synovial MSCs derived from the knee joints of aging human donors possess chondrogenic potential. Under serum-free culturing conditions and in the absence of dexamethasone, BMP-2 and BMP-7 were the most potent inducers of this transformation process.