Attenuated expression of SECIS binding protein 2 causes loss of telomeric reserve without affecting telomerase

The family of selenoproteins have a broad range of functions, including protection against oxidative damage. Previous studies have shown that elevated levels of oxidative damage can induce accelerated loss of telomeric DNA during proliferation of mammalian cells. The incorporation of selenocysteine (Sec) into proteins in mammalian cells requires the Sec insertion sequence (SECIS) binding protein 2 (SBP2). Thus in the present study we have assessed the effect of knocking down the expression of SBP2 on telomere length. Following knock-down of SBP2 expression in two different human cell lines, the MSTO mesothelioma cell line (5 Kb average telomere length) and SY5Y neuroblastoma cell line (4.2 Kb average telomere length), we observed a significant reduction (−0.6 to −1.1 Kb; P  0.01) in telomere length as compared to control cells. This reduction in telomere length was independent of affects on telomerase, since both telomerase activity levels and Tert mRNA expression levels were not altered by knock-down of SBP2 expression. Furthermore, telomeres were particularly sensitive to S1 nuclease digestion following SBP2 knock-down, indicating an increased frequency of oxidative damage-induced lesions in the telomeric DNA in these cells. Together, these observations imply that selenoproteins may help protect telomeric reserve in mammalian cells.     

Direct effect of cocaine on epigenetic regulation of PKC gene repression in the fetal rat heart

Maternal cocaine administration during gestation caused a down-regulation of PKC expression in the heart of adult offspring resulting in an increased sensitivity to ischemia and reperfusion injury. The present study investigated the direct effect of cocaine in epigenetic modification of PKC gene repression in the fetal heart. Hearts were isolated from gestational day 17 fetal rats and treated with cocaine in an ex vivo organ culture system. Cocaine treatment for 48 h resulted in significant decreases in PKC protein and mRNA abundance and increases in CpG methylation at two SP1 binding sites in the PKC promoter region (− 346 and − 268). Electrophoretic mobility shift assays demonstrated that CpG methylation of both SP1 sites inhibited SP1 binding. Consistently, chromatin immunoprecipitation assays showed that cocaine treatment significantly decreased binding of SP1 to the SP1 sites in the intact fetal heart. Reporter gene assays revealed that site-directed mutations of CpG methylation at both SP1 sites significantly reduced the PKC promoter activity while methylation of a single site at either − 346 or − 268 did not have a significant effect. The causal effect of increased methylation in the cocaine-induced down-regulation of PKC was demonstrated with the use of DNA methylation inhibitors. The presence of either 5-aza-2′-deoxycytodine or procainamide blocked the cocaine-induced increase in SP1 sites methylation and decrease in PKC mRNA. The results demonstrate a direct effect of cocaine in epigenetic modification of DNA methylation and programming of cardiac PKC gene repression linking prenatal cocaine exposure and pathophysiological consequences in the heart of adult offspring.     

Effects of mild calorie restriction and high-intensity interval walking in middle-aged and older overweight Japanese

We investigated whether a combination of mild calorie restriction (MCR) and high-intensity interval walking (HIW) improved physical fitness more than HIW alone in middle-aged and older overweight Japanese (40–69 years old, BMI  23.6 kg/m²). Forty-seven women and 16 men were divided into MCR + HIW and HIW groups. All subjects performed HIW: 5 sets of 3-min low-intensity walking (40% peak aerobic capacity for walking, VO_2peak) and 3-min high-intensity walking (70% VO_2peak) per day, 4 days per week, for 16 weeks while energy expenditure was monitored with a tri-axial accelerometer. The MCR + HIW group consumed meal replacement formula (240 kcal): a mixture of low-carbohydrates and -fat and high-protein, for either lunch or dinner everyday and therefore, had 87% of the energy intake of the HIW group during the intervention period. Although the HIW group showed improvements in BMI, blood pressure, and several blood chemicals, the MCR + HIW group had greater improvement. Moreover, the medical expenditure for the 6 months including the intervention period was 59% lower in the MCR + HIW group than in the HIW group. Our strategy of a short-term combination of MCR and HIW may thus prevent lifestyle-associated diseases and improve health in middle-aged and older overweight Japanese.     

Involvement of Src in L-type Ca channel depression induced by macrophage migration inhibitory factor in atrial myocytes

Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine that controls inflammatory processes, and inflammation is known to play an important role in the pathogenesis of atrial fibrillation (AF). The present study sought to investigate whether MIF expression is responsible for the changes in L-type Ca²⁺ currents (I_Ca,L) seen in AF. Whole-cell voltage-clamp recordings and biochemical assays were used to study the regulation and expression of I_Ca,L in human atrial myocytes and in HL-1 cells. Basal I_Ca,L was reduced in AF compared to sinus rhythm (SR) controls, mRNA and protein levels of the pore-forming α_1C subunit of L-type Ca²⁺ channel (LCC α_1C) were also decreased, while MIF expression levels were increased in AF. Levels of Src and activated Src (p-Src Y⁴¹⁶) were higher in AF than in SR. Treatment of atrial myocytes from a patient with SR with human recombinant MIF (rMIF) (40 nM, 1 h) was found to depress I_Ca,L amplitudes, while mouse rMIF (20 or 40 nM, 24 h) suppressed peak I_Ca,L in HL-1 cells by  69% and  83% in a concentration-dependent manner. Mouse rMIF impaired the time-dependent recovery from inactivation of I_Ca,L and down-regulated LCC α_1C subunit levels. The depression of I_Ca,L and decrease of LCC protein levels induced by rMIF were prevented by the Src inhibitors genistein and PP1. These results implicate MIF in the electrical remodeling that accompanies AF, probably by decreasing I_Ca,L amplitudes through impairment of channel function, down-regulation of LCC α_1C subunit levels, and the activation of c-Src kinases in atrial myocytes.     

Interethnic differences of CYP2C9 alleles in healthy Hungarian and Roma population samples: Relationship to worldwide allelic frequencies

CYP2C9 gene polymorphisms are widely studied in several ethnic groups, however they are less known in the Roma population. The aim of this work was to study the ethnic differences of the CYP2C9 allele distribution in a healthy Roma population in order to compare them with a healthy Hungarian population. A total of 535 Hungarian and 465 Roma volunteers were genotyped for the CYP2C92 (Arg144Cys) and CYP2C93 (Ile359Leu) allelic variants by PCR-RFLP assay. The frequencies of the CYP2C91, 2 and 3 alleles in the Hungarian population were 0.787, 0.125, and 0.088 and in Roma 0.727, 0.118, and 0.155, respectively. We found a significant difference in CYP2C93 prevalence between the Hungarian and Roma populations, which have therapeutic consequences (p < 0.005). The distribution of 1/1, 1/2, 1/3, 2/2, 2/3, and 3/3 genotypes in Hungarians were 0.620, 0.195, 0.139, 0.021, 0.015, and 0.011, while in Roma were 0.533, 0.168, 0.219, 0.011, 0.047, and 0.022, respectively. A significant difference was found between the Hungarian and Roma populations regarding the 1/1, 1/3 and the 2/3 (p < 0.005) genotypes. This is the first study to investigate the polymorphisms of CYP2C9 gene in the two largest populations in Hungary, healthy Hungarians and Roma. The prevalence of variant CYP2C9 alleles in the Hungarian population is similar to that observed in other European populations. In contrast, the Roma population differs from Hungarians, from most of other Caucasian groups, and from Indians in the incidence of CYP2C9 common variants. The difference in allele distribution patterns between the two populations studied has therapeutic implications as it influences the optimization of therapies.     

Netrin-1 prevents ischemia/reperfusion-induced myocardial infarction via a DCC/ERK1/2/eNOSs1177/NO/DCC feed-forward mechanism

We have recently shown that a novel endothelial mitogen netrin-1 potently stimulates nitric oxide (NO) production via a DCC-ERK1/2 dependent mechanism. In view of the well-established cardioprotective role of NO, the present study investigated whether netrin-1 is cardioprotective via NO signaling in the heart. Netrin-1 receptor DCC was abundantly expressed in the C57BL/6J mouse hearts. Perfusion of heart with netrin-1 (100 ng/mL) using a Langendorff system significantly increased NO production. Under ischemia/reperfusion (I/R), netrin-1 induced a substantial reduction in infarct size (21.8 ± 4.9% from 42.5 ± 3.6% in the controls), which was accompanied by an augmented production of NO. Pre-perfusion with DCC-antibody, U0126 (MEK1/2 inhibitor), L-NAME or PTIO (NO scavenger) attenuated protective effects of netrin-1 on infarct size and NO production, indicating upstream roles of DCC and ERK1/2 in NO production, as well as an essential role of NO in cardioprotection. Netrin-1 induced reduction in infarct size was significantly attenuated in DCC+/− mice, confirming an intermediate role of DCC. In additional experiments we found netrin-1 increased ERK1/2 and eNOS_s1177 phosphorylation, and DCC protein expression, which was diminished by I/R. Furthermore, netrin-1-induced DCC upregulation was NO and ERK1/2-dependent, implicating a feed-forward mechanism. DAF-AM staining revealed enhanced NO production in both cardiac endothelial cells (ECs) and myocytes. In primarily isolated cardiomyocytes, netrin-1 also increased NO production, DCC abundance and ERK1/2 phosphorylation. Of note, cardiac apoptosis was significantly attenuated by netrin-1, which was reversed by DCC-antibody, U0126, L-NAME or PTIO. In summary, our data clearly demonstrate that netrin-1 potently protects the heart from I/R injury by stimulating NO production from cardiac ECs and myocytes. This potent effect is mediated by a DCC/ERK1/2/eNOS_s1177/NO/DCC feed-forward mechanism in both cell types.     

Gene expression profiling and prediction of clinical outcome in ovarian cancer

Epithelial ovarian cancer is the most lethal gynaecological cancer. Despite debulking surgery and platinum/taxane-based chemotherapy, the prognosis remains poor with 25% 5-year survival. Current histo-clinical prognostic factors are insufficient to capture the complex cascade of events that drive the heterogeneous clinical behaviour of the disease. There is a crucial need to identify new prognostic subclasses of disease as well as new therapeutic targets. Today, DNA microarrays allow the simultaneous and quantitative analysis of the mRNA expression levels of thousands of genes in a tumour sample. They have been applied to ovarian cancer research for predicting initial surgical resectability, survival and response to first-line chemotherapy. The first results are promising. In this review, we describe recent applications of DNA microarrays in ovarian cancer research and discuss some issues to address in the near future to allow the technology to reach its full potential in clinical practice.     

Changes of intra-mitochondrial Ca in adult ventricular cardiomyocytes examined using a novel fluorescent Ca indicator targeted to mitochondria

In this study a Ca²⁺ sensitive protein was targeted to the mitochondria of adult rabbit ventricular cardiomyocytes using an adenovirus transfection technique. The probe (Mitycam) was a Ca²⁺-sensitive inverse pericam fused to subunit VIII of human cytochrome c oxidase. Mitycam expression pattern and Ca²⁺ sensitivity was characterized in HeLa cells and isolated adult rabbit cardiomyocytes. Cardiomyocytes expressing Mitycam were voltage-clamped and depolarized at regular intervals to elicit a Ca²⁺ transient. Cytoplasmic (Fura-2) and mitochondrial Ca²⁺ (Mitycam) fluorescence were measured simultaneously under a range of cellular Ca²⁺ loads. After 48 h post-adenoviral transfection, Mitycam expression showed a characteristic localization pattern in HeLa cells and cardiomyocytes. The Ca²⁺ sensitive component of Mitycam fluorescence was 12% of total fluorescence in HeLa cells with a K_d of  220 nM. In cardiomyocytes, basal and beat-to-beat changes in Mitycam fluorescence were detected on initiation of a train of depolarizations. Time to peak of the mitochondrial Ca²⁺ transient was slower, but the rate of decay was faster than the cytoplasmic signal. During spontaneous Ca²⁺ release the relative amplitude and the time course of the mitochondrial and cytoplasmic signals were comparable. Inhibition of mitochondrial respiration decreased the mitochondrial transient amplitude by  65% and increased the time to 50% decay, whilst cytosolic Ca²⁺ transients were unchanged. The mitochondrial Ca²⁺ uniporter (mCU) inhibitor Ru360 prevented both the basal and transient components of the rise in mitochondrial Ca²⁺. The mitochondrial-targeted Ca²⁺ probe indicates sustained and transient phases of mitochondrial Ca²⁺ signal, which are dependent on cytoplasmic Ca²⁺ levels and require a functional mCU.     

Mitochondrial free calcium regulation during sarcoplasmic reticulum calcium release in rat cardiac myocytes

Cardiac mitochondria can take up Ca²⁺, competing with Ca²⁺ transporters like the sarcoplasmic reticulum (SR) Ca²⁺-ATPase. Rapid mitochondrial [Ca²⁺] transients have been reported to be synchronized with normal cytosolic [Ca²⁺]_i transients. However, most intra-mitochondrial free [Ca²⁺] ([Ca²⁺]_mito) measurements have been uncalibrated, and potentially contaminated by non-mitochondrial signals. Here we measured calibrated [Ca²⁺]_mito in single rat myocytes using the ratiometric Ca²⁺ indicator fura-2 AM and plasmalemmal permeabilization by saponin (to eliminate cytosolic fura-2). The steady-state [Ca²⁺]_mito dependence on [Ca²⁺]_i (with 5 mM EGTA) was sigmoid with [Ca²⁺]_mito < [Ca²⁺]_i for [Ca²⁺]_i below 475 nM. With low [EGTA] (50 μM) and 150 nM [Ca²⁺]_i (± 15 mM Na⁺) cyclical spontaneous SR Ca²⁺ release occurred (5–15/min). Changes in [Ca²⁺]_mito during individual [Ca²⁺]_i transients were small ( 2–10 nM/beat), but integrated gradually to steady-state. Inhibition SR Ca²⁺ handling by thapsigargin, 2 mM tetracaine or 10 mM caffeine all stopped the progressive rise in [Ca²⁺]_mito and spontaneous Ca²⁺ transients (confirming that SR Ca²⁺ releases caused the [Ca²⁺]_mito rise). Confocal imaging of local [Ca²⁺]_mito (using rhod-2) showed that [Ca²⁺]_mito rose rapidly with a delay after SR Ca²⁺ release (with amplitude up to 10 nM), but declined much more slowly than [Ca²⁺]_i (time constant 2.8 ± 0.7 s vs. 0.19 ± 0.06 s). Total Ca²⁺ uptake for larger [Ca²⁺]_mito transients was  0.5 μmol/L cytosol (assuming 100:1 mitochondrial Ca²⁺ buffering), consistent with prior indirect estimates from [Ca²⁺]_i measurements, and corresponds to  1% of the SR Ca²⁺ uptake during a normal Ca²⁺ transient. Thus small phasic [Ca²⁺]_mito transients and gradually integrating [Ca²⁺]_mito signals occur during repeating [Ca²⁺]_i transients.     

Heterogeneous expression of SNARE proteins SNAP-23, SNAP-25, Syntaxin1 and VAMP in human parathyroid tissue

In regulated exocytosis synaptosomal-associated protein of 25 kDa (SNAP-25) is one of the key-players in the formation of SNARE (soluble N-ethylmaleimide-sensitive fusion attachment protein receptor) complex and membrane fusion. SNARE proteins are essentially expressed in neurons, neuroendocrine and endocrine cells. Whether parathyroid cells express these proteins is not known. In this study, we have examined the expression of the SNARE protein SNAP-25 and its cellular homologue SNAP-23, as well as syntaxin1 and VAMP (vesicle-associated membrane protein) in samples of normal parathyroid tissue, chief cell adenoma, and parathyroid carcinoma, using immunohistochemistry and Western blot analysis. SNAP-23 and VAMP were evenly expressed in all studied parathyroid tissues using immunohistochemistry and/or Western blot analysis. SNAP-25 (and Syntaxin1) was not expressed in normal parathyroid tissue, but in approximately 20% of chief cell adenomas, and in 45% of parathyroid carcinoma samples. It is likely that the SNARE proteins SNAP-23 and VAMP play a role in the stimulus-secretion coupling and exocytosis of parathyroid hormone as these proteins were expressed in all of the parathyroid samples we studied. In particular, preferential expression of SNAP-23 rather than SNAP-25 provides an explanation of the high level of PTH secretion that occurs under conditions of low cytoplasmic free Ca²⁺ concentration (around 0.1 μmol/l). SNAP-25 (and Syntaxin1) appears to be a tumour-specific protein(s) in parathyroid tissues since its expression was restricted to pathological tissues.     

Kinetic evidence for modulation by glycophorin A of a conformational equilibrium between two states of band 3 (SLC4A1) bound reversibly by the competitive inhibitor DIDS

Recent evidence has suggested that erythrocytes naturally deficient in glycophorin A (GPA) have a reduced V_max for monovalent anion exchange. Unanswered is whether miss-folding of band 3 during biosynthesis, or the absence of GPA modulation of properly folded band 3 is responsible. Here, I determine the effect of selective depletion of GPA on the kinetics of reversible binding of the competitive transport inhibitor DIDS (4,4′-diisothiocyanato-2,2′-stilbenedisulfonate) to properly folded band 3. Reversible binding of DIDS follows biphasic kinetics: a fast phase {DIDS + band 3  (DIDS − band 3), k₁, k_− 1} and a slower phase {(DIDS − band 3)  (DIDS − band 3), k₂, k_− 2}. Selective depletion of GPA was accomplished by pretreating membranes with Triton X-100, over a range where erythrocyte hemolysis is inhibited by the detergent (0% to 0.03%, v/v). Pretreatment with sublytic Triton X-100: (a) virtually completely depleted GPA, (b) did not deplete membrane-bound band 3, and (c) slowed the overall rate of reversible binding of DIDS to band 3. Data analysis and model simulation studies indicated that the decrease in the rate of binding of DIDS was due exclusively to a decrease in k_− 2, with no change in the initial rate of binding. Thus, depletion of GPA does not alter the native conformation of band 3 at the DIDS binding site, but rather modulates a conformational equilibrium between two states of the binary complex formed by the competitive inhibitor DIDS, reversibly bound to properly folded band 3.     

Mechanistic insights into folic acid-dependent vascular protection: Dihydrofolate reductase (DHFR)-mediated reduction in oxidant stress in endothelial cells and angiotensin II-infused mice: A novel HPLC-based fluorescent assay for DHFR activity

Folate supplementation improves endothelial function in patients with hyperhomocysteinemia. Mechanistic insights into potential benefits of folate on vascular function in general population however, remain mysterious. Expression of dihydrofolate reductase (DHFR) was markedly increased by folic acid (FA, 50 μmol/L, 24 h) treatment in endothelial cells. Tetrahydrofolate (THF) is formed after incubation of purified DHFR or cellular extracts with 50 μmol/L of substrate dihydrofolic acid. THF could then be detected and quantified by high performance liquid chromatography (HPLC) with a fluorescent detector (295/365 nm). Using this novel and sensitive assay, we found that DHFR activity was significantly increased by FA. Furthermore, FA improved redox status of Ang II treated cells by increasing H₄B and NO bioavailability while decreasing superoxide (O₂⁻) production. It however failed to restore NO levels in DHFR siRNA-transfected or methotrexate pre-treated cells, implicating a specific and intermediate role of DHFR. In mice orally administrated with FA (15 mg/kg/day, 16 days), endothelial upregulation of DHFR expression and activity occurred in correspondence to improved NO and H₄B bioavailability, and this was highly effective in reducing Ang II infusion (0.7 mg/kg/day, 14 days)-stimulated aortic O₂⁻ production. 5′-methyltetrahydrofolate (5′-MTHF) levels, GTPCH1 expression and activity remained unchanged in response to FA or Ang II treatment in vitro and in vivo. FA supplementation improves endothelial NO bioavailability via upregulation of DHFR expression and activity, and protects endothelial cells from Ang II-provoked oxidant stress both in vitro and in vivo. These observations likely represent a novel mechanism (intermediate role of DHFR) whereby FA induces vascular protection.     

Vaccination of European badgers (Meles meles) with BCG by the subcutaneous and mucosal routes induces protective immunity against endobronchial challenge with Mycobacterium bovis

Mycobacterium bovis is endemic in badger (Meles meles) populations of Ireland and the United Kingdom and infected badgers are a potential source of infection for cattle. In domestic livestock tuberculosis causes economic losses from lost production and the costs associated with eradication programmes, and in addition there is a risk of zoonotic infection. Whereas culling is currently used to control tuberculous badger populations in Ireland, vaccination, if it were available, would be preferred. A study was undertaken to examine the protective responses of badgers vaccinated either by the subcutaneous or mucosal (intranasal and conjunctival) routes with bacille Calmette-Guérin (BCG), when challenged with M. bovis by the endobronchial route. Three groups of badgers were used. The first group (n = 4) was vaccinated with 5 × 10⁵ colony forming units (cfu) of BCG by subcutaneous injection. In the second group (n = 5) badgers were vaccinated via the mucosal route by instilling 1.0 × 10⁵ cfu into each conjunctival sac and spraying 1.0 × 10⁵ cfu into each nostril (final vaccine dose of 4 × 10⁵ cfu). The control (n = 5) badgers served as a non-vaccinated group. Twelve weeks post-vaccination all badgers in the three groups were challenged with 10⁴ cfu of M. bovis by endobronchial inoculation. At 12 weeks post-infection all badgers were examined post-mortem to assess the pathological and bacteriological responses to challenge. Gross and histological lesions of tuberculosis were seen in all challenged badgers and M. bovis was recovered from all challenged badgers. However, across six of the eight parameters used to measure disease severity, the infection in the vaccinated badgers was significantly less severe than in the control group. The BCG vaccine induced a significant protective effect in the badgers and the protective immunity was generated by subcutaneous and mucosal vaccination.     

Distribution of CYP1A1*2A polymorphism in adult patients with acute lymphoblastic leukemia in a Mexican population

The effects of the CYP1A12A genotype on susceptibility to leukemia have received particular attention in recent years because this enzyme plays a central role in the activation of carcinogens. Several polymorphisms at the CYP1A1 locus have been identified and their genotypes appear to exhibit population frequencies that depend on ethnicity. We evaluated the role of the CYP1A12A genotype in adults with acute lymphoblastic leukemia (ALL) by genotyping 210 patients and 228 healthy controls from the Mexican population. The frequency of the CC genotype was 8% (18/228) in the control group and 42% (88/210) in ALL patients; the frequency of the CT genotype was 39% (89/228) and 29.5% (62/210), respectively; and that of the TT genotype was 53% (121/228) and 28.5% (60/210), respectively. The odds ratio was 8.4 (95% CI, 4.7–15.5; P < 0.001). These data indicate that the CYP1A12A genotype contributes significantly to susceptibility to adult ALL in a sample of the Mexican population.     

Detection of myocardial ischemia by vessel-specific leads derived from the 12-lead electrocardiogram and its subsets

Currently used electrocardiographic criteria for identifying patients with ST-elevation myocardial infarction (STEMI) perform with high specificity but low sensitivity. Our aim was to enhance ischemia-detection ability of conventional STEMI criteria based on 12-lead electrocardiogram (ECG) by adding new criteria using 3 vessel-specific leads (VSLs) derived from 12-lead ECG. Study data consisted of 12-lead ECGs acquired during 99 ischemic episodes caused by balloon inflation in, respectively, left anterior descending coronary artery (LAD; n = 35), right coronary artery (RCA; n = 47), and left circumflex coronary artery (LCx; n = 17). ST deviation was measured at J point in 12 standard leads, and for 3 VSLs, its value was derived from 12-lead ECG by using 8 independent predictor leads or just a pair of precordial leads combined with a pair of limb leads. Mean values of sensitivity (SE) and specificity (SP) of ischemia detection achieved with conventional STEMI vs VSL criteria were then obtained from bootstrap trials. We found that the detection of ischemic state by conventional criteria achieved the mean SE/SP of 60%/96% in the total set of ischemic episodes, 74%/97% in the LAD subgroup, 60%/94% in the RCA subgroup, and 36%/100% in the LCx subgroup. In comparison, the mean SE/SP values of VSLs derived from 8 independent leads of 12-lead ECG were, at 125-μV threshold, 76%/96% in the total set, 91%/97% in the LAD subgroup, 70%/94% in the RCA subgroup, and 71%/100% in the LCx subgroup (with asterisk denoting a statistically significant increase). The mean SE/SP of VSLs derived from some of the 4-predictor lead sets (namely, those including lead V₃) matched or exceeded values achieved by VSLs derived from 8 predictors; for instance, with predictor leads I, II, V₃, V₆ derived VSLs attained at 125-μV threshold the mean SE/SP of 80%/95% in the total set, 91%/97% in the LAD subgroup, 74%/92% in the RCA subgroup, and 71%/100% in the LCx subgroup. Based on these results, we conclude that, in our data set, 3 VSLs derived from the complete standard 12-lead ECG—and even from its subsets—can identify acute ischemia better than existing STEMI criteria.     

Reduced DIDS-sensitive chloride conductance in Ae1-/- mouse erythrocytes

The resting membrane potential of the human erythrocyte is largely determined by a constitutive Cl⁻ conductance  100-fold greater than the resting cation conductance. The 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid (DIDS)-sensitive electroneutral Cl⁻ transport mediated by the human erythroid Cl⁻/HCO₃⁻ exchanger, AE1 (SLC4A1, band 3) is > 10,000-fold greater than can be accounted for by the Cl⁻ conductance of the red cell. The molecular identities of conductive anion pathways across the red cell membrane remain poorly defined. We have examined red cell Cl⁻ conductance in the Ae1^−/− mouse as a genetic test of the hypothesis that Ae1 mediates DIDS-sensitive Cl⁻ conductance in mouse red cells. We report here that wildtype mouse red cell membrane potential resembles that of human red cells in the predominance of its Cl⁻ conductance. We show with four technical approaches that the DIDS-sensitive component of erythroid Cl⁻ conductance is reduced or absent from Ae1^−/− red cells. These results are consistent with the hypothesis that the Ae1 anion exchanger polypeptide can operate infrequently in a conductive mode. However, the fragile red cell membrane of the Ae1^−/− mouse red cell exhibits reduced abundance or loss of multiple polypeptides. Thus, loss of one or more distinct, DIDS-sensitive anion channel polypeptide(s) from the Ae1^−/− red cell membrane cannot be ruled out as an explanation for the reduced DIDS-sensitive anion conductance.     

Sam So Eum, a herb extract, as the remedy for allergen-induced asthma in mice

We studied administering Sam So Eum (SSE) as a herbal medicine to treat asthma in mice and we discussed the mechanism of restoring the immuno-modulating cytokines such as IL-10 and IFN-γThe mice treated with SSE did not show any significant variation in their body weight and they looked very similar to the controlled ones. The SSE-treated mice showed reduced levels of airway responsiveness to methacholine, and these levels were initially elevated by the induction of asthma compared to the control group. The SSE elevated production level of IFN-γ, which was down-regulated upon induction of asthma. This result implies that SSE can change the Th1/Th2 ratio through Th1-skewing reactions, and that SSE can decrease airway hyperresponsiveness by changing the Th1/Th2 ratio. The treatment with SSE also restored the IL-10 level to that of the naive condition. This means that SSE reduced the airway inflammation through this pathway. The ovalbumin (OVA)-specific antibody (total Ig) production in the serum was also decreased upon SSE treatment. Prednisolone (PD) was used as positive control. The effectiveness of SSE was almost the same as that of PD. These results suggest the possibility of using SSE for the treatment of patients with asthma, and its therapeutic efficacy involves restoring the IFN-γ and IL-10 levels.     

Prevalence of iodine deficiency in Europe in 2010

The adverse effects of iodine deficiency (ID)  intellectual impairment, damaged reproduction, goiter and hypo- and hyperthyroidism  are well known and easily corrected with salt iodization, but they continue to impair health and socioeconomic development, with more than two billion people at risk worldwide. During the major global expansion of salt iodization over the past four decades, much of Europe has remained iodine deficient. Although every European country endorsed the goal of eliminating iodine deficiency at the 1992 World Health Assembly, control of iodine deficiency has received low priority in much of Europe. However, there has been recent progress in the region and the number of children with low iodine intakes has decreased by ca. 30% since 2003. This paper presents an estimate of the prevalence of iodine deficiency in Europe in 2010, based on a systematic review to update the WHO Vitamin and Mineral Nutrition Information System (VMNIS) database.     

Pro12Ala polymorphism in PPAR gamma 2 associated with essential hypertension in Chinese nonagenarians/centenarians

The Pro12Ala polymorphism of PPAR γ 2 has been shown to influence hypertension and the benefit of longevity in previous studies. We examined whether the polymorphism was related to essential hypertension among long-lived subjects (90 years). The Pro12Ala variant was examined using polymerase chain reaction restriction fragment length polymorphism in a population-based sample of 839 long-lived subjects (mean 94 years SD 4 years, aged 90–108 years). The genotype frequencies of the Pro12Ala polymorphism were 0.2% Ala12Ala, 9.4% Pro12Ala and 90.4% Pro12Pro in all participants. The frequency of the Ala12 allele was 3.45% in the hypertension group and 6.92% among the normotension group (P = 0.001). Moreover, in the total study population, Ala12 allele carriers had lower levels of triglycerides (1.03 ± 0.5 mmol/L (means ± SD) vs. 1.25 ± 0.61 mmol/L; P < 0.001). In conclusion, these results suggest that the Pro12Ala polymorphism of the PPAR γ 2 gene is associated with hypertension and triglycerides levels in Chinese nonagenarians/centenarians.