Worldwide, multiple Fusarium mycotoxins occur as contaminants of cereals with important impacts on human and animal health. The aim of this study was to investigate the effects of the widespread Fusarium secondary metabolite enniatin (ENN), a cyclic hexadepsipeptide, on human cell growth and survival. While short-term exposure (up to 8 h) to ENN at nanomolar concentrations slightly but significantly stimulated cell proliferation, it showed profound apoptosis-inducing effects especially against various human cancer cell types at low micromolar concentrations (already after 24 h of treatment). Several cellular changes indicative for programmed cell death such as cell shrinkage, chromatin condensation, DNA fragmentation, and apoptotic body formation were observed. Correspondingly, the cleavage of poly(ADP-ribosyl)polymerase and the activation of multiple caspases accompanied a distinct loss of mitochondrial membrane potential. To investigate the impact of apoptosis- and cell cycle-regulating proteins on ENN activity, HCT116 cells with homozygously disrupted p53, p21, or bax genes were analyzed. In vitality assays, no significant influences of these proteins on the anticancer activity of ENN were detectable. In contrast, 3H-thymidine incorporation revealed a significantly more efficient block of DNA synthesis in p53 wild-type as compared to knock-out cells. Accordingly, fluorescence-activated cell sorting analysis demonstrated a stronger ENN-induced cell cycle arrest in the G0/G1 phase. Profound ENN-mediated induction of p53 and the p53-downstream cell cycle inhibitor p21 were detectable in p53 wild-type cells by Western blotting. P53-independent p21 induction was also detectable at higher ENN concentrations in p53 (-/-) cells. In contrast, bax activation by ENN was independent of the cellular p53 status. In summary, our results suggest that short-term exposure to very low ENN concentrations, for example, via food intake, might have tumor-promoting functions based on growth stimulation. In contrast, elevated ENN concentrations exert profound p53-dependent cytostatic and p53-independent cytotoxic activities especially against human cancer cells, suggesting a potential quality of ENN as an anticancer drug.

Rationale: Alveolar liquid clearance is regulated by Na 1 uptake through the apically expressed epithelial sodium channel (ENaC) and basolaterally localized Na 1 -K 1 -ATPase in type II alveolar epithelial cells. Dysfunction of these Na 1 transporters during pulmonary inflammation can contribute to pulmonary edema.Objectives: In this study, we sought to determine the precise mechanism by which the TIP peptide, mimicking the lectin-like domain of tumor necrosis factor (TNF), stimulates Na 1 uptake in a homologous cell system in the presence or absence of the bacterial toxin pneumolysin (PLY).Methods: We used a combined biochemical, electrophysiological, and molecular biological in vitro approach and assessed the physiological relevance of the lectin-like domain of TNF in alveolar liquid clearance in vivo by generating triple-mutant TNF knock-in mice that express a mutant TNF with deficient Na 1 uptake stimulatory activity.Measurements and Main Results: TIP peptide directly activates ENaC, but not the Na 1 -K 1 -ATPase, upon binding to the carboxyterminal domain of the a subunit of the channel. In the presence of PLY, a mediator of pneumococcal-induced pulmonary edema, this binding stabilizes the ENaC-PIP2-MARCKS complex, which is necessary for the open probability conformation of the channel and preserves ENaC-a protein expression, by means of blunting the protein kinase C-a pathway. Triple-mutant TNF knock-in mice are more prone than wild-type mice to develop edema with low-dose intratracheal PLY, correlating with reduced pulmonary ENaC-a subunit expression.Conclusions: These results demonstrate a novel TNF-mediated mechanism of direct ENaC activation and indicate a physiological role for the lectin-like domain of TNF in the resolution of alveolar edema during inflammation.

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BackgroundChronic kidney disease (CKD) and end-stage renal disease (ESRD) represent worldwide health problems with an epidemic extent. Therefore, attention must be given to the optimisation of patient care, as gaps in the care of CKD and ESRD patients are well documented. As part of a multidisciplinary patient care strategy, clinical pharmacy services have led to improvements in patient care. The purpose of this study was to summarise the available evidence regarding the role and impact of clinical pharmacy services for these patient populations.MethodsA literature search was conducted using the Medline, Embase and International Pharmaceutical Abstracts databases to identify relevant studies on the impact of clinical pharmacists on CKD and ESRD patients, regarding disease-oriented and patient-oriented outcomes, and clinical pharmacist interventions on drug-related problems.ResultsAmong a total of 21 studies, only four (19%) were controlled trials. The majority of studies were descriptive (67%) and before-after studies (14%). Interventions comprised general clinical pharmacy services with a focus on detecting, resolving and preventing drug-related problems, clinical pharmacy services with a focus on disease management, or clinical pharmacy services with a focus on patient education in order to increase medication knowledge. Anaemia was the most common comorbidity managed by clinical pharmacists, and their involvement led to significant improvement in investigated disease-oriented outcomes, for example, haemoglobin levels. Only four of the studies (including three controlled trials) presented data on patient-oriented outcomes, for example, quality of life and length of hospitalisation. Studies investigating the number and type of clinical pharmacist interventions and physician acceptance rates reported a mean acceptance rate of 79%. The most common reported drug-related problems were incorrect dosing, the need for additional pharmacotherapy, and medical record discrepancies.ConclusionsFew high-quality trials addressing the benefit and impact of clinical pharmacy services in CKD and ESRD patients have been published. However, all available studies reported some positive impact resulting from clinical pharmacist involvement, including various investigated outcome measures that could be improved. Additional randomised controlled trials investigating patient-oriented outcomes are needed to further determine the role of clinical pharmacists and the benefits of clinical pharmacy services to CKD and ESRD patients.

The pore-forming toxin Panton–Valentine leukocidin (PVL) is carried by community-acquired methicillin-resistant Staphylococcus aureus and associated with necrotizing pneumonia together with poor prognosis of infected patients. Although the cell-death–inducing properties of PVL have previously been examined, the pulmonary immune response to PVL is largely unknown. Using an unbiased transcriptional profiling approach, we show that PVL induces only 29 genes in mouse alveolar macrophages, which are associated with TLR signaling. Further studies indicate that PVL directly binds to TLR2 and induces immune responses via NF-κB in a TLR2, CD14, MyD88, IL-1R–associated kinase 1, and TNFR-associated factor 6-dependent manner. PVL-mediated inflammation is independent of pore formation but strongly depends on the LukS subunit and is suppressed in CD14/TLR2−/− cells. In vivo PVL or LukS induced a robust inflammatory response in lungs, which was diminished in CD14/TLR2−/− mice. These results highlight the proinflammatory properties of PVL and identify CD14/TLR2 as an essential receptor complex for PVL-induced lung inflammation.