Butyrate Induces Glutathione S-Transferase in Human Colon Cells and Protects From Genetic Damage by 4-Hydroxy-2-Nonenal

Butyrate, one of the major products of gut fermentation, is known to inhibit proliferation, induce apoptosis and differentiation, and increase phase II enzyme activities in tumor cells, whereas little information is available on protective effects in less-transformed colon cells. The aim of this study was to investigate whether the chemoprotective mechanism of glutathione S-transferase (GST) induction by butyrate could also play a role in earlier stages of colon carcinogenesis and whether chemoresistance of cells toward the endogenous genotoxic risk factor 4-hydroxy-2-nonenal (HNE) could be a consequence of butyrate treatment. As cell models, we used the human tumor cell lines HT29 and HT29 clone 19A, a differentiated subclone with properties resembling primary colon cells. We determined the expression of GSTP1 protein (enzyme-linked immunosorbent assay), the major GST in HT29, GSTP1 mRNA (Northern blotting), GST activity, intracellular glutathione, and total protein. The genotoxic impact of HNE (100-200 μM) was compared in butyrate-treated and nontreated cells using single-cell microgel electrophoresis. Our results show that GSTP1 mRNA, GSTP1 protein, GST activity, and total protein were increased (1.2- to 2.5-fold) and glutathione levels were maintained after 24- 72 h of incubation with 4 mM butyrate. Moreover, a marked reduction of HNE-induced genotoxicity was caused by preincubation with butyrate. Butyrate also induced the phosphorylation of extracellular signal-regulated kinases (ERK1/2, Western blotting) after 5-30 min, which indicates a regulation of GST expression by this signal pathway. Most effects were greater in HT29 parent cells than in clone cells. In conclusion, butyrate enhances expression of GST and other proteins in both cell lines, which leads to an enhanced chemoprotection, reducing the impact of HNE genotoxicity. Thus butyrate could play a role in early and later stages of cancer prevention by reducing exposure to relevant risk factors.     

Intraventricular entrapment of a Sapien-3 balloon in transapical TAVR: A near missed catastrophe

Balloon rupture is an uncommon complication during balloon-expandable transcatheter aortic valve replacement (TAVR). We describe a balloon rupture and tearing with intraventricular entrapment complicating transapical-TAVR, as well as our bailout retrieval of the failed device.     

Association between Body Iron Status and Leukocyte Telomere Length,a Biomarker of Biological Aging,in a Nationally Representative Sample of US Adults

Background

Excess iron levels can induce oxidative stress and could therefore affect telomere attrition. However, little is known about the impact of body iron status on telomere length.

Do I Just Look Stressed or am I Stressed? Work-related Stress in a Sample of Italian Employees

Work-related stress is becoming a significant problem in Italy and it is therefore essential to advance the theory and methodology required to detect this phenomenon at work. Thus, the aim of this paper is to propose a new method for evaluating stress at work by measuring the discrepancies between employees’ perceptions of stress and their leaders’ evaluation of the stress of their subordinates. In addition, a positive impression scale was added to determine whether workers might give socially desirable responses in organizational diagnosis. Over 1,100 employees and 200 leaders within several Italian organizations were involved in this study. Structural equation modeling was used to test such new method for evaluating stress in a model of stress at work that incorporates relationships among individual (positive impression), interpersonal (workplace bullying) and organizational factors (working conditions, welfare culture, training). Results showed that the leaders’ capacity to understand subordinates’ stress is associated with subordinates’ psychological well-being since higher disagreement between self and leaders’ ratings was related to lower well-being. We discuss the implications of healthy leadership for the development of healthy organizations.     

Racial Differences in the Associations of Posttraumatic Stress and Insomnia With Body Mass Index Among Trauma-Exposed Veterans

Posttraumatic stress is associated with increased body mass index (BMI) and rates of obesity. Black adults are at greater risk for obesity, trauma exposure, development of posttraumatic stress disorder, and comorbid sleep problems compared to White adults. Accordingly, Black adults with a history of trauma exposure may be at greater risk for elevated BMI associated with posttraumatic stress and insomnia. Multiple linear regression was used to examine race as a moderator of the relationship between posttraumatic symptoms and insomnia with BMI in a sample of Black and White trauma-exposed Veterans (N = 171), controlling for age and sex. There was a significant interaction of race with PTSD (p = 0.042) and insomnia symptoms (p = 0.045) on BMI. Simple slopes showed a significant positive association of posttraumatic stress and BMI among Black (p = 0.003), but not White Veterans (p = 0.590). Similarly, insomnia was significantly associated with greater BMI for Black (p = 0.023), but not White Veterans (p = 0.496). Posttraumatic stress and insomnia may play a particularly important role in the development of weight related health problems among Black Veterans. Early identification and treatment of these symptoms may reduce the risk of obesity among this vulnerable population.