Favipiravir Protects Enterocytes From Cell Death After Inflammatory Storm.

Over the past years, inflammatory bowel disease (IBD) treatment has become more targeted, anticipating the use of immune-modifying therapies at an earlier stage. During the treatment process prevention and management of viral infections hold significant importance. The protective role of favipiravir on enterocytes which are affected by inflammation is still unknown. We aim to analyze the effects of favipiravir on enterocytes after an inflammatory condition. We conducted a 2,5-diphenyl-2H-tetrazolium bromide (MTT) assay to assess the cytotoxicity of favipiravir on intestinal epithelioid cells (IEC-6). To mimic the inflammation model in cell culture conditions, we exposed IEC-6 cells to tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). The cells were categorized into four groups: control, inflammation model, application of favipiravir before inflammation (prophylactic), and application of favipiravir after inflammation (treatment). We assessed the presence and distribution of caspase 1, caspase 3, interleukin 6 (IL6), interleukin 8 (IL8), mixed lineage kinase domain-like protein (MLKL), receptor-interacting protein kinase 1 (RIPK1), and TNF-α using indirect immunoperoxidase staining. TNF-α and IL8 levels were analyzed with enzyme-linked immunosorbent assay (ELISA) in a culture medium. Caspase 1 was observed to be strong (+++) in the treatment group and weak (+) in the prophylactic group compared to the inflammation group. Caspase 3 was weak (+) in the inflammation group, and it was strong (+++) in the prophylactic and treatment group, the increase in the treatment group was significant. Therefore administering favipiravir before inducing inflammation appears to control the inflammatory caspase pathway in intestinal enterocytes, protecting them from inflammatory responses, while the caspase 3-dependent apoptotic pathway may not be active in enterocytes during inflammation. IL6 and IL8 were negative (-) in control, IL6 was weak (+) in inflammation and favipiravir treated groups; IL8 increased significantly in favipiravir groups compared to control and inflammation groups. Consequently, favipiravir may trigger IL6 release, initiating the inflammatory pathway and potentially enhancing IL8 interactions with other cytokines. TNF-α immunoreactivity was strong (+++) in the inflammation group, while it was moderate (++) in favipiravir-administered groups. MLKL immunoreactivity was strong (+++) in all groups, RIPK1 was weak (+) in control, strong (+++) in the inflammation and treatment group, moderate (++) in the prophylactic group, and the increase in inflammation and treatment group was significant compared to control. Our findings suggest that in the treatment group, necroptosis was triggered by increased MLKL and RIPK1, key players in inflammation and cell death. After immunocytochemical evaluation, our findings suggest that, after the onset of inflammation, favipiravir may play a role in cell death by increasing necroptosis rather than apoptosis.

Antibacterial and antibiofilm activities of ceragenins against Achromobacter species isolated from cystic fibrosis patients.

Achromobacter species, which are recognized as emerging pathogens isolated from patients with cystic fibrosis, are capable of forming biofilm in the respiratory tract in patients and innate multidrug resistance to antimicrobials. CSAs are cationic salt derivatives that mimic the activity of antimicrobial peptides and exhibit antimicrobial activity against bacteria. In this study, the in vitro activities of various ceragenins against Achromobacter-species biofilms were investigated comparatively with a conventional antibiotic (meropenem). Biofilm-formation inhibition and biofilm-adhesion inhibition were investigated on five strong biofilm-producing strains. The lowest MIC50 result was obtained with CSA-13. All of the tested CSAs showed significant biofilm inhibitory activity in the manner of a time- and concentration-dependent effect. To the best of our knowledge, this is the first article to evaluate the antibacterial and antibiofilm activities of tested CSAs against Achromobacter species.

Comparative in vitro activities of meropenem in combination with colistin, levofloxacin, or chloramphenicol against Achromobacter xylosoxidans strains isolated from patients with cystic fibrosis.

OBJECTIVES: Achromobacter xylosoxidans is an emerging pathogen in cystic fibrosis (CF). Relatively little is known about its clinical impact and optimal management. In the present study, the in vitro bactericidal activities of meropenem, either alone or in combination with colistin, levofloxacin, or chloramphenicol, were assessed using A. xylosoxidans strains isolated from CF patients. The synergistic interactions of these combinations were also investigated. METHODS: Minimal inhibitory concentrations (MICs) were determined by microbroth dilution. Bactericidal and synergistic effects of the tested antibiotic combinations were assessed by using the time-kill curve technique. RESULTS: Based on the time-kill curves, we found that meropenem-colistin combinations have bactericidal and synergistic activities for 24 h against A. xylosoxidans strains, both at 1 × MIC and 4 × MIC. Although synergistic interactions were seen with meropenem-levofloxacin combinations, no bactericidal interactions were observed. Additionally, the meropenem-chloramphenicol combinations were found to be neither bactericidal nor synergistic. No antagonism was observed with any combination tested. CONCLUSIONS: This study's findings could have important implications for empirical or combination antimicrobial therapy with tested antibiotics.

Comparative In Vitro Activities of First and Second-Generation Ceragenins Alone and in Combination with Antibiotics Against Multidrug-Resistant Klebsiella pneumoniae Strains.

OBJECTIVES: The ceragenins, or CSAs, were designed to mimic the activities of antimicrobial peptides and represent a new class of antimicrobial agent. The aim of this study was to comparatively investigate the antimicrobial activities of first/second generation ceragenins and various antibiotics against multidrug-resistant (MDR) Klebsiella pneumoniae, including colistin-resistant bacteria. Also, the synergistic effects of two ceragenins with colistin or meropenem were investigated with six K. pneumoniae strains presenting different resistant patterns. METHODS: Minimal inhibition concentrations (MICs) were determined by the microdilution method according to the CLSI. Antibiotic combination studies were evaluated by the time-kill curve method. RESULTS: MIC50 and MIC90 values of tested ceragenins ranged from 8 to 32 mg/L and 16 to 128 mg/L. Overall, among the ceragenins tested, CSA-131 showed the lowest MIC50 and MIC90 values against all microorganisms. The MICs of the ceragenins were similar or better than tested antibiotics, except for colistin. Synergistic activities of CSA-131 in combination with colistin was found for strains both at 1× MIC and 4× MIC. No antagonism was observed with any combination. CONCLUSIONS: First-generation ceragenins CSA-13 and CSA-44 and second-generation ceragenins CSA-131, CSA-138 and CSA-142 have significant antimicrobial effects on MDR K. pneumoniae. Mechanisms allowing resistance to clinical comparator antibiotics like colistin did not impact the activity of ceragenins. These results suggest that ceragenins may play a role in treating infections that are resistant to known antibiotics.

Is CHA2DS2-VASc Score Different in Patients with Non-valvular Atrial Fibrillation Suffering from Cerebral and Non-cerebral Thromboembolism?CHA2DS2-VASc Score in Thromboembolism.

BACKGROUND: Thromboembolic complication is directly related to CHA2DS2-VASc score in patients with non-valvular atrial fibrillation (NVAF). In this study we compared the CHA2DS2-VASc score and in-hospital mortality between NVAF patients with non-cerebral thromboembolism and those with stroke. METHODS: We retrospectively reviewed medical records of 213 patients with NVAF who experienced stroke and 115 patients with NVAF who experienced non-cerebral thromboembolism between 2010 and 2015. In all patients, CHA2DS2-VASc score before the event was calculated. RESULTS: The mean CHA2DS2-VASc score was similar in patients with stroke (4.52±1.66) and those with non-cerebral thromboembolism (4.29±2.02) (p=0.196). In-hospital mortality rate was similar between the groups (19% vs. 17%, p=0.756). The rates of coronary artery disease (52% vs. 38%, p=0.014), prior transient ischemic attack (16% vs. 5%, p=0.001), and prior non-cerebral thromboembolism (18% vs. 3%, p<0.001) were higher in patients with non-cerebral thromboembolism. Warfarin (55% vs. 14% p<0.001) and antiplatelet use (56% vs. 40%, p=0.004) was more common in the non-cerebral embolism group, while non-vitamin K antagonist oral anticoagulant (NOAC) use was more common in the stroke group (15% vs. 7% p=0.026). CONCLUSION: The patients with stroke had similar CHA2DS2-VASc score and in-hospital mortality compared to patients with non-cerebral thromboembolism.