Effects of Azithromycin on Behavior, Pathologic Signs, and Changes in Cytokines, Chemokines, and Neutrophil Migration in C57BL/6 Mice Exposed to Dextran Sulfate Sodium

Dietary Supplementation of Haskap Berry (Lonicera caerulea L.) Anthocyanins and Probiotics Attenuate Dextran Sulfate Sodium-Induced Colitis: Evidence from an Experimental Animal Model

Haskap berry (Lonicera caerulea L.) is a rich dietary source of anthocyanins with potent anti-inflammatory properties. In this study, isolated haskap berry anthocyanins were encapsulated in maltodextrin and inulin (3:1) by freeze-drying to improve stability and bioavailability. The structural properties of microcapsules, encapsulation yield, efficiency, recovery, and powder retention were evaluated. The microcapsules that exhibited the highest encapsulation efficiency (60%) and anthocyanin recovery (89%) were used in the dextran sulfate sodium (DSS)-induced acute colitis in mice. Thirty-five BALB/c male mice of seven weeks old were divided into seven dietary supplementation groups (n = 5) to receive either free anthocyanins, encapsulated anthocyanins (6.2 mg/day), or probiotics (1 × 109 CFU/day) alone or as combinations of anthocyanin and probiotics. As observed by clinical data, free anthocyanin and probiotic supplementation significantly reduced the severity of colitis. The supplementary diets suppressed the DSS-induced elevation of serum inflammatory (interleukin (IL)-6 and tumor necrosis factor) and apoptosis markers (B-cell lymphoma 2 and Bcl-2-associated X protein) in mice colon tissues. The free anthocyanins and probiotics significantly reduced the serum IL-6 levels. In conclusion, the dietary supplementation of haskap berry anthocyanins and probiotics protects against DSS-induced colitis possibly by attenuating mucosal inflammation, and this combination has the potential as a health-promoting dietary supplement and nutraceutical.

The immunomodulatory effects of probiotics and azithromycin in dextran sodium sulfate-induced ulcerative colitis in rats via TLR4-NF-κB and p38-MAPK pathway

Ulcerative colitis (UC), a chronic autoimmune disease of the gut with a relapsing and remitting nature, considers a major health-care problem. DSS is a well-studied pharmacologically-induced model for UC. Toll-Like Receptor 4 (TLR4) and its close association with p-38-Mitogen-Activated Protein Kinase (p-38 MAPK) and nuclear factor kappa B (NF-κB) has important regulatory roles in inflammation and developing UC. Probiotics are gaining popularity for their potential in UC therapy. The immunomodulatory and anti-inflammatory role of azithromycin in UC remains a knowledge need. In the present rats-established UC, the therapeutic roles of oral probiotics (60 billion probiotic bacteria per kg per day) and azithromycin (40 mg per kg per day) regimens were evaluated by measuring changes in disease activity index, macroscopic damage index, oxidative stress markers, TLR4, p-38 MAPK, NF-κB signaling pathway in addition to their molecular downstream; tumor necrosis factor alpha (TNFα), interleukin (IL)1β, IL6, IL10 and inducible nitric oxide synthase (iNOS). After individual and combination therapy with probiotics and azithromycin regimens, the histological architecture of the UC improved with restoration of intestinal tissue normal architecture. These findings were consistent with the histopathological score of colon tissues. Each separate regimen lowered the remarkable TLR4, p-38 MAPK, iNOS, NF-κB as well as TNFα, IL1β, IL6 and MDA expressions and elevated the low IL10, glutathione and superoxide dismutase expressions in UC tissues. The combination regimen possesses the most synergistic beneficial effects in UC that, following thorough research, should be incorporated into the therapeutic approach in UC to boost the patients' quality of life.

Establishment of Food Allergy Model in Dextran Sulfate Sodium Induced Colitis Mice

Food allergy (FA) has become a global food safety issue. Evidence suggests that inflammatory bowel disease (IBD) can increase the incidence of FA, but it is mostly based on epidemiological studies. An animal model is pivotal for unraveling the mechanisms involved. However, dextran sulfate sodium (DSS)-induced IBD models may cause substantial animal losses. To better investigate the effect of IBD on FA, this study aimed to establish a murine model to fit both IBD and FA symptoms. Firstly, we compared three DSS-induced colitis models by monitoring survival rate, disease activity index, colon length, and spleen index, and then eliminated the colitis model with a 7-day administration of 4% due to high mortality. Moreover, we evaluated the modeling effects on FA and intestinal histopathology of the two models selected and found the modeling effects were similar in both the colitis model with a 7-day administration of 3% DSS and the colitis model with long-term administration of DSS. However, for animal survival reasons, we recommend the colitis model with long-term administration of DSS.

Expression of Human Interleukin 8 in Mice Alters Their Natural Behaviors

Objective

To examine the effects of human interleukin (IL) 8 expression on mouse behavior.

Methods

A mouse line expressing human IL8 in the intervertebral discs (IVD) and cartilaginous tissues (hIL8⁺ ) was generated. Mouse spontaneous behaviors, including locomotion, climbing, rearing, grooming, eating, drinking, and immobility were recorded with a fully automatic, non-invasive platform.

Results

Distance traveled by the hIL8⁺ mice declined with age compared with control littermates, and male hIL8⁺ mice traveled a shorter distance than male controls and females of either genotype (p <0.05). The hIL8⁺ mice also spent less time in locomotion than control mice (p <0.01), and male hIL8⁺ mice spent the least amount of time and had lowest count in locomotion compared with the other 3 groups at 12 weeks of age or greater (p <0.05). The hIL8⁺ mice spent less time climbing than controls, and male mice spent less time climbing than female mice of the same genotype (p <0.01). The hIL8⁺ mice spent more time eating and less time drinking than controls, and all mice spent less time eating and more time drinking with increasing age. Finally, hIL8⁺ mice spent more time immobile than controls, and male hIL8⁺ mice spent more time immobile than any other group (p <0.05).

Conclusion

The hIL8⁺ mice, especially hIL8⁺ males, showed reduced ambulation and climbing. Mice showed age-related decrease in eating and increase in drinking and grooming time that was also influenced by expression of hIL8. These changes in natural behaviors in control mice are consistent with functional decline with age. Effects of hIL8 superimposed on the natural aging process could involve systemic (e.g., on the brain) and local (e.g., in the spine and joint tissues) mechanisms. Future exploration of these mechanisms might be productive.

Nonantimicrobial Actions of Macrolides: Overview and Perspectives for Future Development

Macrolides are among the most widely prescribed broad spectrum antibacterials, particularly for respiratory infections. It is now recognized that these drugs, in particular azithromycin, also exert time-dependent immunomodulatory actions that contribute to their therapeutic benefit in both infectious and other chronic inflammatory diseases. Their increased chronic use in airway inflammation and, more recently, of azithromycin in COVID-19, however, has led to a rise in bacterial resistance. An additional crucial aspect of chronic airway inflammation, such as chronic obstructive pulmonary disease, as well as other inflammatory disorders, is the loss of epithelial barrier protection against pathogens and pollutants. In recent years, azithromycin has been shown with time to enhance the barrier properties of airway epithelial cells, an action that makes an important contribution to its therapeutic efficacy. In this article, we review the background and evidence for various immunomodulatory and time-dependent actions of macrolides on inflammatory processes and on the epithelium and highlight novel nonantibacterial macrolides that are being studied for immunomodulatory and barrier-strengthening properties to circumvent the risk of bacterial resistance that occurs with macrolide antibacterials. We also briefly review the clinical effects of macrolides in respiratory and other inflammatory diseases associated with epithelial injury and propose that the beneficial epithelial effects of nonantibacterial azithromycin derivatives in chronic inflammation, even given prophylactically, are likely to gain increasing attention in the future. SIGNIFICANCE STATEMENT: Based on its immunomodulatory properties and ability to enhance the protective role of the lung epithelium against pathogens, azithromycin has proven superior to other macrolides in treating chronic respiratory inflammation. A nonantibiotic azithromycin derivative is likely to offer prophylactic benefits against inflammation and epithelial damage of differing causes while preserving the use of macrolides as antibiotics.

Targeting Neutrophils to Treat Acute Respiratory Distress Syndrome in Coronavirus Disease

This review describes targeting neutrophils as a potential therapeutic strategy for acute respiratory distress syndrome (ARDS) associated with coronavirus disease 2019 (COVID-19), a pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Neutrophil counts are significantly elevated in patients with COVID-19 and significantly correlated with disease severity. The neutrophil-to-lymphocyte ratio can serve as a clinical marker for predicting fatal complications related to ARDS in patients with COVID-19. Neutrophil-associated inflammation plays a critical pathogenic role in ARDS. The effector functions of neutrophils, acting as respiratory burst oxidants, granule proteases, and neutrophil extracellular traps, are linked to the pathogenesis of ARDS. Hence, neutrophils can not only be used as pathogenic markers but also as candidate drug targets for COVID-19 associated ARDS.