Trends of the potentially inappropriate medication consumption over 10 years in older adults in the East of France.

PURPOSE: To describe the trends of potentially inappropriate medication (PIM) use in older adults from 1995 to 2004 in the East of France, by using the 1997 Beers criteria and its French update, and to assess risk factors for this PIM use. METHODS: We carried out a repeated cross-sectional study using data collected among people aged >/=65 years, examined in the Center for Preventive Medicine. Studied variables were socio-demographic, clinical data, medication consumption and the self-health status. Joinpoint regression analysis was used to estimate the temporal changes in PIM rate. RESULTS: 30 683 participants were included. 51.2% were women. The mean age was 70.1 +/- 4.3 years [65-99]. The annual overall rate of PIM use decreased significantly during the study period. These rates range from 14.9% in 1995 to 9.0% in 2004 according the Beers criteria (-3.4% per year) and from 33.5% in 1995 to 19.3% in 2004 according to the French update criteria (-3.6% per year). The annual rate of medication users increased during the same period (+0.75% per year). The risk of PIM consumption increased with age, number of drugs and frequency of the visits to the physician (OR = 1.26 [1.18-1.35]). This risk was also higher among women (OR = 1.29 [1.18-1.40]), elderly living alone (OR = 1.09 [1.02-1.17]) and with those with low education level (OR = 1.19 [1.02-1.38]). CONCLUSION: This study shows a decrease in PIM consumption. Despite an increase of drug use in the elderly, an improving of the quality of this consumption remains possible.

Trueness verification of actual creatinine assays in the European market demonstrates a disappointing variability that needs substantial improvement. An international study in the framework of the EC4 creatinine standardization working group.

BACKGROUND: The European In Vitro Diagnostics (IVD) directive requires traceability to reference methods and materials of analytes. It is a task of the profession to verify the trueness of results and IVD compatibility. METHODS: The results of a trueness verification study by the European Communities Confederation of Clinical Chemistry (EC4) working group on creatinine standardization are described, in which 189 European laboratories analyzed serum creatinine in a commutable serum-based material, using analytical systems from seven companies. Values were targeted using isotope dilution gas chromatography/mass spectrometry. Results were tested on their compliance to a set of three criteria: trueness, i.e., no significant bias relative to the target value, between-laboratory variation and within-laboratory variation relative to the maximum allowable error. RESULTS: For the lower and intermediate level, values differed significantly from the target value in the Jaffe and the dry chemistry methods. At the high level, dry chemistry yielded higher results. Between-laboratory coefficients of variation ranged from 4.37% to 8.74%. Total error budget was mainly consumed by the bias. Non-compensated Jaffe methods largely exceeded the total error budget. Best results were obtained for the enzymatic method. The dry chemistry method consumed a large part of its error budget due to calibration bias. CONCLUSIONS: Despite the European IVD directive and the growing needs for creatinine standardization, an unacceptable inter-laboratory variation was observed, which was mainly due to calibration differences. The calibration variation has major clinical consequences, in particular in pediatrics, where reference ranges for serum and plasma creatinine are low, and in the estimation of glomerular filtration rate.

Contrasting effects of peroxisome-proliferator-activated receptor (PPAR)gamma agonists on membrane-associated prostaglandin E2 synthase-1 in IL-1beta-stimulated rat chondrocytes: evidence for PPARgamma-independent inhibition by 15-deoxy-Delta12,14prostaglandin J2.

Microsomal prostaglandin E synthase (mPGES)-1 is a newly identified inducible enzyme of the arachidonic acid cascade with a key function in prostaglandin (PG)E2 synthesis. We investigated the kinetics of inducible cyclo-oxygenase (COX)-2 and mPGES-1 expression with respect to the production of 6-keto-PGF1alpha and PGE2 in rat chondrocytes stimulated with 10 ng/ml IL-1beta, and compared their modulation by peroxisome-proliferator-activated receptor (PPAR)gamma agonists. Real-time PCR analysis showed that IL-1beta induced COX-2 expression maximally (37-fold) at 12 hours and mPGES-1 expression maximally (68-fold) at 24 hours. Levels of 6-keto-PGF1alpha and PGE2 peaked 24 hours after stimulation with IL-1beta; the induction of PGE2 was greater (11-fold versus 70-fold, respectively). The cyclopentenone 15-deoxy-Delta12,14prostaglandin J2 (15d-PGJ2) decreased prostaglandin synthesis in a dose-dependent manner (0.1 to 10 microM), with more potency on PGE2 level than on 6-keto-PGF1alpha level (-90% versus -66% at 10 microM). A high dose of 15d-PGJ2 partly decreased COX-2 expression but decreased mPGES-1 expression almost completely at both the mRNA and protein levels. Rosiglitazone was poorly effective on these parameters even at 10 microM. Inhibitory effects of 10 microM 15d-PGJ2 were neither reduced by PPARgamma blockade with GW-9662 nor enhanced by PPARgamma overexpression, supporting a PPARgamma-independent mechanism. EMSA and TransAM analyses demonstrated that mutated IkappaBalpha almost completely suppressed the stimulating effect of IL-1beta on mPGES-1 expression and PGE2 production, whereas 15d-PGJ2 inhibited NF-kappaB transactivation. These data demonstrate the following in IL-1-stimulated rat chondrocytes: first, mPGES-1 is rate limiting for PGE2 synthesis; second, activation of the prostaglandin cascade requires NF-kappaB activation; third, 15d-PGJ2 strongly inhibits the synthesis of prostaglandins, in contrast with rosiglitazone; fourth, inhibition by 15d-PGJ2 occurs independently of PPARgamma through inhibition of the NF-kappaB pathway; fifth, mPGES-1 is the main target of 15d-PGJ2.

Impact of standardized calibration on the inter-assay variation of 14 automated assays for the measurement of creatinine in human serum.

PURPOSE: The aim of our study was to measure the inter-assay variation and accuracy of serum creatinine assays and to assess the effect of standardized calibration procedures on this variability. METHODS: We analyzed 30 human sera and three reference materials, using 17 creatinine assays (12 colorimetric, 4 enzymatic and 1 HPLC). We compared two standardized calibration procedures, using either a reference material or secondary standards, to that recommended by the manufacturers. RESULTS: For assays calibrated according to the manufacturers' recommendations, the median inter-assay coefficient of variation (CV) was 14.2% for 20 low samples (45-150 microM), and 7.7% for 10 high samples (250-350 microM). The CV was significantly influenced by the calibration procedure, but none of the standardized calibration procedures significantly improved the inter-assay variability. However, a significant decrease in CV was noted within each type of assay method (colorimetric or enzymatic) when the standardized calibration used standards of level(s) close to the concentrations to be measured. Only the compensated Jaffe technique and the amido-hydrolase assay showed bias of less than 10%. CONCLUSIONS: Standardizing calibration procedures is unlikely to decrease the analytical variability of creatinine assays enough to allow uniform and reliable use of the equations for estimation of glomerular filtration rate.

Effect of chemopreventive agents on glutathione S-transferase P1-1 gene expression mechanisms via activating protein 1 and nuclear factor kappaB inhibition.

Glutathione S-transferase P1-1 (GSTP1-1) is a phase II drug metabolism enzyme implicated in carcinogenesis and development of resistance to anti-cancer drugs. It was previously shown that both activating protein 1 (AP-1) and nuclear factor kappaB (NF-kappaB) are involved in its regulation. In the present study we examined the inhibitory effect of several chemopreventive agents on the tumor necrosis factor (TNF) alpha- or 12-O-tetradecanoylphorbol 13 acetate (TPA)-induced promoter activity of GSTP1-1, as demonstrated by transient transfection experiments in K562 and U937 leukemia cells. Our results provide evidence for a differential effect of chemopreventive agents such as beta-lapachone, emodin, sanguinarine and capsaicin, which significantly inhibit reporter gene expression as well as TNFalpha- and TPA-induced binding of AP-1 and NF-kappaB, whereas trans-anethole and silymarin do not produce any inhibitory effect. Our results demonstrate the ability of selected chemopreventive agents to decrease GSTP1-1 gene expression mechanisms and could thus contribute to reduce the incidence of glutathione related drug resistance in human leukemia.

Induction of apoptosis by curcumin: mediation by glutathione S-transferase P1-1 inhibition.

Expression of glutathione S-transferase P1-1 (GSTP1-1) is correlated to carcinogenesis and resistance of cancer cells against chemotherapeutic agents. Curcumin, a natural compound extracted from Curcuma longa, has shown strong antioxidant and anticancer properties and also the ability to regulate a wide variety of genes that require activating protein 1 and nuclear factor kappaB (NF-kappaB) activation. In the present study, we examined the inhibitory effect of curcumin on the expression of GSTP1-1 mRNA as well as protein, and we correlated this inhibition with the apoptotic effect of curcumin on K562 leukemia cells. Curcumin efficiently inhibited the tumour necrosis factor alpha- and phorbol ester-induced binding of AP-1 and NF-kappaB transcription factors to sites located on the GSTP1-1 gene promoter. TNFalpha-induced GSTP1-1 promoter activity was also inhibited by curcumin as shown by reporter gene assay. In parallel, curcumin induced pro-caspases 8 and 9 as well as poly ADP ribose polymerase cleavage and thus leading to apoptosis in K562 cells. Our results overall add a novel role for curcumin as this chemoprotective compound could contribute to induce apoptosis by its ability to inhibit the GSTP1-1 expression at the level of transcription.

Erythrocytes as targets for gamma-glutamyltranspeptidase initiated pro-oxidant reaction.

Gamma-glutamyltranspeptidase (GGT) is a well known cell plasma membrane and serum circulating enzyme. In clinical chemistry, GGT is used as a marker of alcohol consumption and drug uptake. Serum GGT activity varies in hepatobiliary diseases and cancer. This enzyme is involved in glutathione (GSH) metabolism, which is generally associated with antioxidant properties. However, in recent years, findings from our group and from others showed that GGT-catalysed extracellular metabolism of GSH leads, in the presence of iron, to the generation of reactive oxygen species (ROS). It was demonstrated that those highly reactive species oxidise lipids, cell surface protein thiols or activate transcriptional factors such as Nuclear Factor kappaB (NFkappaB). The objective of the present work is to determine whether the red blood cells are targets for plasma GGT-initiated pro-oxidant reaction. The results obtained demonstrate that the GGT/GSH/iron system oxidises isolated erythrocyte membranes. A significant release of haemoglobin and a decrease of erythrocyte deformability are also observed. In addition, in vivo studies showed a relationship between plasma GGT activity and erythrocyte deformability in 20 studied subjects. In conclusion, GGT-mediated ROS production is able to oxidise erythrocytes and thus disturbs their functions.

Enhanced resistance of HeLa cells to cisplatin by overexpression of gamma-glutamyltransferase.

Gamma-glutamyltransferase (GGT), which is a key enzyme for the cellular glutathione (GSH) homeostasis, was shown to be overexpressed in human tumor cells selected for resistance to cisplatin and to influence the resistance of experimental tumors in vivo. We first established that cisplatin treatment of HeLa cells was accompanied by an early 3-fold induction of GGT synthesis, enhancing the possibility that this enzyme plays an important role in the cell defenses against this anticancer drug. This role was then studied using a GGT-transfected HeLa cell line (HeLa-GGT) exhibiting 10 times the activity of the parental HeLa cells (120-150 and 10-14 mU/mg protein, respectively). Both cell lines showed comparable intracellular GSH levels and cisplatin resistance when cultured in high (250 microM) or low (50 microM) cysteine-containing medium. When 50 microM of GSH were included in the low-cysteine culture medium only HeLa-GGT cells partially recovered their intracellular GSH and exhibited an increased resistance to cisplatin. Cisplatin treatment also inhibited GGT-dependent production of reactive oxygen species, a process depending on the availability of cysteinylglycine produced during GSH catabolism. Furthermore, we showed that cisplatin forms adducts with cysteinylglycine 10 times more rapidly than with GSH, and that these adducts were formed only in the extracellular medium of HeLa GGT cells. This extracellular mechanism could at least partially account for the increased resistance of GGT-rich cells to cisplatin.