A genome-wide association study confirms APOE as the major gene influencing survival in long-lived individuals

We conducted a case–control genome-wide association study (GWAS) of human longevity, comparing 664,472 autosomal SNPs in 763 long-lived individuals (LLI; mean age: 99.7 years) and 1085 controls (mean age: 60.2 years) from Germany. Only one association, namely that of SNP rs4420638 near the APOC1 gene, achieved genome-wide significance (allele-based P = 1.8 × 10^?10). However, logistic regression analysis revealed that this association, which was replicated in an independent German sample, is fully explicable by linkage disequilibrium with the APOE allele ?4, the only variant hitherto established as a major genetic determinant of survival into old age. Our GWAS failed to identify any additional autosomal susceptibility genes. One explanation for this lack of success in our study would be that GWAS provide only limited statistical power for a polygenic phenotype with loci of small effect such as human longevity. A recent GWAS in Dutch LLI independently confirmed the APOE–longevity association, thus strengthening the conclusion that this locus is a very, if not the most, important genetic factor influencing longevity.     

Better IVF outcomes following improvements in laboratory air quality

Background

It has been proved that air quality is crucial for the success of IVF because of the presence of volatile organic compounds (VOCs), microbes, and perfumes, all of which can be harmful to embryo development in vitro. Therefore IVF laboratories are equipped with high efficiency particulate air (HEPA), and activated carbon filters plus positive pressure for air particulate control, with or without CODA system. Here we introduce a new technology using specially treated Honeycomb matrix media aligned in the Landson ™ series system for our laboratory air purification and its impact on IVF outcome.

Methods

Air samples were collected outside and inside the laboratory, and intra-incubator at three different time points, before and after changing carbon filters and after Landson system installation, and we correlated air compounds measure variation with IVF outcome from 1403 cycles.

Results

An improvement of air quality was confirmed with passages of total VOCs from 0.42 mg/m³, 30.48 mg/m³, 9.62 mg/m3, to 0.1 mg/m³, 2.5 mg/m³, 2.19 mg/m³ through 0.07 mg/m³, 0.16 mg/m³, 0.29 mg/m³, outside the laboratory, inside laboratory and intra-incubator respectively at three separated air sampling times. A clear decrease was observed in some VOCs such as formaldehyde, ethylene, acethylene, propylene, SO2, pentane, NOx, benzene, Hallon-1211, CFC and alcohol.At the same time a significant difference (P < 0.05) was found between the third testing time TT3 after carbon filter change and Landson system installation and the first testing time TT1 before carbon filter change in fertilization rate 83.7 % vs 70.1 %, embryo cleavage rate 97.35 % vs 90.8 %, day 5 blastocyst formation rate 51.1 % vs 41.7 %, and pregnancy/implantation rates 54.6 %, 34.4 % vs 40.6 %, 26.4 %.

Conclusion

Air purification by the new technology of Landson ™ series significantly improved IVF laboratory air quality, and embryo quality, thus increased pregnancy and implantation rates.     

Mechanophysical-chemotherapy combinations: a dual approach to combat cancer

Cancer treatment, owing to its myriad limitations, has often been a formidable challenge to both the practitioners as well as researchers. There has been a continued effort in designing newer and successful strategies to obtain optimal results. One such strategy includes the elucidation of a combinatorial approach of the conventional chemotherapy protocol with various mechanophysical methods. This opinion article discusses that how two thrust areas like targeting cancerous cells using a novel drug-delivery system and mechanophysical methods of killing them can be amalgamated into a complete new vector, which is driven with precision, specificity, accuracy, and better efficacy. This approach relies on devising a mechanophysical responsive vehicle, which could be added to other anticancer therapies. The new combined tool would then kill the cancer cells not just by releasing the chemotherapeutic drug at the desired site but also by killing individual cells through the purported mechanophysical stimuli. Summarily, the resultant vector generates an angle influenced by the direction of the mechanophysical vector, leading to a better therapeutic modality.     

Correction of HDL dysfunction in individuals with diabetes and the haptoglobin 2-2 genotype

OBJECTIVE—Pharmacogenomics is a key component of personalized medicine. The Israel Cardiovascular Events Reduction with Vitamin E Study, a prospective placebo-controlled study, recently demonstrated that vitamin E could dramatically reduce CVD in individuals with diabetes and the haptoglobin (Hp) 2-2 genotype (40% of diabetic individuals). However, because of the large number of clinical trials that failed to demonstrate benefit from vitamin E coupled with the lack of a mechanistic explanation for why vitamin E should be beneficial only in diabetic individuals with the Hp 2-2 genotype, enthusiasm for this pharmacogenomic paradigm has been limited. In this study, we sought to provide such a mechanistic explanation based on the hypothesis that the Hp 2-2 genotype and diabetes interact to promote HDL oxidative modification and dysfunction.RESEARCH DESIGN AND METHODS—Hb and lipid peroxides were assessed in HDL isolated from diabetic individuals or mice with the Hp 1-1 or Hp 2-2 genotypes. HDL function was assessed based on its ability to promote cholesterol efflux from macrophages. A crossover placebo-controlled study in Hp 2-2 diabetic humans and in Hp 1-1 and Hp 2-2 diabetic mice assessed the ability of vitamin E to favorably modify these structural and functional parameters.RESULTS—Hb and lipid peroxides associated with HDL were increased and HDL function was impaired in Hp 2-2 diabetic individuals and mice. Vitamin E decreased oxidative modification of HDL and improved HDL function in Hp 2-2 diabetes but had no effect in Hp 1-1 diabetes.CONCLUSIONS—Vitamin E significantly improves the quality of HDL in Hp 2-2 diabetic individuals.Pharmacogenomics is a key component of personalized medicine (1). Therapy targeted to a specific patient based on his or her genetically determined pathophysiology responsible for the disease offers the possibility of significantly improving patient care and reducing costs. However, despite the clear public health and economic benefits that would be attained by such an approach, this paradigm has not been successfully applied to a common disease.Cardiovascular disease (CVD) is responsible for 75% of deaths among individuals with diabetes, and yearly expenditures for CVD in diabetes exceed $200 billion (2). Neither conventional risk factors nor the degree of glycemic control adequately predict which individuals with diabetes develop CVD, suggesting the existence of genetic susceptibility factors.A polymorphism in the haptoglobin (Hp) gene may define which individuals with diabetes are at greatest risk of CVD. There exist two classes of alleles at the Hp locus denoted 1 and 2 with three possible Hp genotypes 1-1, 2-1, and 2-2 (3). In five independent longitudinal studies performed in ethnically and geographically diverse groups, individuals with the Hp 2-2 genotype and diabetes were found to have a two- to fivefold increased risk of CVD compared with diabetic individuals without the Hp 2-2 genotype (4–8). The prevalence of the Hp 2-2 genotype in the diabetic population in most Western countries is ∼40%, making this a common polymorphism.The Hp polymorphism differs from nearly all polymorphisms being assessed in genome-wide association studies because it is a functional polymorphism (3). Understanding functional differences between the Hp 1 and Hp 2 allelic protein products, particularly in diabetes, may provide insight into why Hp 2-2 diabetic individuals have more CVD and how this increased burden of disease might be reduced. The most well-understood function of Hp is to bind Hb released from erythrocytes (3). Each day, >6 g Hb is released into the bloodstream due to turnover of erythrocytes, and heme iron in this Hb is a powerful oxidizing agent (9,10). Hp, which is present in a 400-fold molar excess to free Hb under normal conditions, binds Hb, reducing its ability to mediate oxidative modifications and directing its removal from the blood via the monocyte/macrophage CD163 Hp-Hb scavenger receptor (11).More than 5 years ago, motivated by in vitro studies demonstrating that the Hp 2-2 protein provides inferior protection against Hb-mediated oxidative stress (9,10), coupled with the suggested importance of oxidative stress in diabetic atherosclerosis (12), we sought to determine whether antioxidant therapy might be particularly beneficial to the Hp 2-2 diabetic cohort. We first tested this hypothesis by examining stored samples from the Heart Outcomes Prevention Evaluation (HOPE) study, which had failed to demonstrate benefit from vitamin E (13). We found that myocardial infarction and CVD death were reduced by >40 and 50%, respectively, in Hp 2-2 diabetic HOPE participants who received vitamin E (14). To prospectively test the hypothesis, we initiated a double-blind randomized placebo-controlled study of vitamin E in 1,434 Hp 2-2 diabetic individuals (Israel Cardiovascular Events Reduction with Vitamin E [ICARE] Study). We found that vitamin E supplementation was associated with a >50% reduction in the combined primary outcome of stroke, myocardial infarction, and cardiovascular death in Hp 2-2 diabetes (7).Enthusiasm for these findings, despite the considerable public health and economic benefits that they suggest, has been muted. Our study comes in the wake of numerous large clinical trials that failed to demonstrate that vitamin E provides any protection against CVD and may be harmful (13,15–20). Further hampering acceptance of this paradigm is the lack of a rational pathophysiological and pharmacogenomic mechanism to explain why Hp 2-2 diabetic individuals have an increased risk of CVD and how vitamin E mitigates this risk. In this study, we sought to provide a rationale for the pharmacogenomic application of the Hp genotype to prevent CVD in diabetes by elucidating the unique structural modifications and dysfunctional nature of HDL in Hp 2-2 diabetic individuals and how these structural and functional changes in HDL are rapidly reversed with vitamin E.     

Vitamin E and diabetic nephropathy in mice model and humans

Diabetes mellitus (DM) is associated with increased oxidative stress due to elevated glucose levels in the plasma. Glucose promotes glycosylation of both plasma and cellular proteins with increased risk for vascular events. Diabetic patients suffer from a higher incidence of cardiovascular complications such as diabetic nephropathy. Haptoglobin (Hp) is an antioxidant plasma protein which binds free hemoglobin, thus preventing heme-iron mediated oxidation. Two alleles exist at the Hp gene locus (1 and 2) encoding three possible Hp genotypes that differ in their antioxidant ability, and may respond differently to vitamin E treatment. Several clinical studies to have shown that Hp 1-1 genotype is a superior antioxidant to the Hp 2-2 genotype and Hp 2-2 genotype is associated with a higher incidence of cardiovascular disease. Vitamin E was found to have beneficial effect in patient and mice with Hp 2-2 genotype. In this review we have summarized the results of our studies in patients with diabetic nephropathy treated with vitamin E and in diabetic mice with different haptoglobin genotypes.     

Selective retroinfusion of GSH and cariporide attenuates myocardial ischemia-reperfusion injury in a preclinical pig model

OBJECTIVE: Reperfusion after ischemia may contribute to loss of myocardial function and increase in infarct size. Scavenging of reactive oxygen species (ROS) by glutathione (GSH) and inhibition of the sodium-proton-exchanger by cariporide are both capable of reducing myocardial reperfusion injury. We tested the efficacy of both agents applied regionally into the myocardium immediately before reperfusion. METHODS: Neonatal rat cardiomyocytes (NRCMs) were exposed to either hypoxia (H, 8 h)/reoxygenation (R, 1 h) or H2O2 (300 microM) in the presence or absence of GSH (10 mg/ml). In pigs (n=5 per group), percutaneous LAD occlusion was performed for 60 min. Application of GSH (250 mg/kg) and/or cariporide (1 mg/kg) was achieved by pressure-regulated retroinfusion of the anterior cardiac vein draining the ischemic area starting 5 min before reopening of the occluded LAD. Seven days later, subendocardial segment shortening (SES) was analyzed by sonomicrometry. Infarct size was determined by methylene-blue staining of the non-ischemic area and tetrazolium red staining of the viable myocardium in the area at risk (AAR). RESULTS: NRCM incubated with GSH (10 mg/ml) survived H/R or H2O2 (0.3 mM) to a larger extent than untreated cells. In pigs, infarct size of untreated hearts (51 +/- 6% of the AAR) was not significantly altered by GSH or cariporide retroinfusion alone (41 +/- 3% and 42 +/- 6%). In contrast, combined retroinfusion of cariporide and GSH significantly reduced infarct size (29 +/- 3%). SES of the infarcted area was improved only after cariporide/GSH retroinfusion as compared to untreated hearts. Additional systemic application of CD18-antibody IB4 (1.5 mg/kg) did not alter infarct size or SES in comparison to GSH/cariporide retroinfusion alone. CONCLUSION: Timely application of GSH scavenging ROS and cariporide targeting ion imbalance provides cardioprotection to the postischemic heart, which is superior to either treatment alone. The lack of an effect of additional IB4 treatment may indicate that GSH/cariporide retroinfusion itself affects leukocyte-dependent reperfusion injury.     

Impact of Antibiotics with Various Target Sites on the Metabolome of Staphylococcus aureus

In this study, global intra- and extracellular metabolic profiles were exploited to investigate the impact of antibiotic compounds with different cellular targets on the metabolome of Staphylococcus aureus HG001. Primary metabolism was largely covered, yet uncommon staphylococcal metabolites were detected in the cytosol of S. aureus, including sedoheptulose-1,7-bisphosphate and the UDP-MurNAc-pentapeptide with an alanine-seryl residue. By comparing the metabolic profiles of unstressed and stressed staphylococcal cells in a time-dependent manner, we found far-ranging effects within the metabolome. For each antibiotic compound, accumulation as well as depletion of metabolites was detected, often comprising whole biosynthetic pathways, such as central carbon and amino acid metabolism and peptidoglycan, purine, and pyrimidine synthesis. Ciprofloxacin altered the pool of (deoxy)nucleotides as well as peptidoglycan precursors, thus linking stalled DNA and cell wall synthesis. Erythromycin tended to increase the amounts of intermediates of the pentose phosphate pathway and lysine. Fosfomycin inhibited the first enzymatic step of peptidoglycan synthesis, which was followed by decreased levels of peptidoglycan precursors but enhanced levels of substrates such as UDP-GlcNAc and alanine-alanine. In contrast, vancomycin and ampicillin inhibited the last stage of peptidoglycan construction on the outer cell surface. As a result, the amounts of UDP-MurNAc-peptides drastically increased, resulting in morphological alterations in the septal region and in an overall decrease in central metabolite levels. Moreover, each antibiotic affected intracellular levels of tricarboxylic acid cycle intermediates.