Water-soluble protein from walleye pollock (Gadus chalcogrammus) suppresses lipopolysaccharide-induced inflammation by attenuating TLR4-MyD88 expression in macrophages

Water-soluble protein (WSP) from fish meat is abundant in the waste effluent generated via the surimi manufacturing process. This study investigated the anti-inflammatory effects and mechanisms of fish WSP using primary macrophages (MΦ) and animal ingestion. MΦ were treated with digested-WSP (d-WSP, 500 µg/mL) with or without lipopolysaccharide (LPS) stimulation. For the ingestion study, male ICR mice (5 weeks old) were fed 4% WSP for 14 days following LPS administration (4 mg/kg body weight). d-WSP decreased the expression of Tlr4, an LPS receptor. Additionally, d-WSP significantly suppressed the secretion of inflammatory cytokines, phagocytic ability, and Myd88 and Il1b expressions of LPS-stimulated macrophages. Furthermore, the ingestion of 4% WSP attenuated not only LPS-induced IL-1β secretion in the blood but also Myd88 and Il1b expressions in the liver. Thus, fish WSP decreases the expressions of the genes involved in the TLR4-MyD88 pathway in MΦ and the liver, thereby suppressing inflammation.

A novel approach for the prevention of ionizing radiation-induced bone loss using a designer multifunctional cerium oxide nanozyme

The disability, mortality and costs due to ionizing radiation (IR)-induced osteoporotic bone fractures are substantial and no effective therapy exists. Ionizing radiation increases cellular oxidative damage, causing an imbalance in bone turnover that is primarily driven via heightened activity of the bone-resorbing osteoclast. We demonstrate that rats exposed to sublethal levels of IR develop fragile, osteoporotic bone. At reactive surface sites, cerium ions have the ability to easily undergo redox cycling: drastically adjusting their electronic configurations and versatile catalytic activities. These properties make cerium oxide nanomaterials fascinating. We show that an engineered artificial nanozyme composed of cerium oxide, and designed to possess a higher fraction of trivalent (Ce³⁺) surface sites, mitigates the IR-induced loss in bone area, bone architecture, and strength. These investigations also demonstrate that our nanozyme furnishes several mechanistic avenues of protection and selectively targets highly damaging reactive oxygen species, protecting the rats against IR-induced DNA damage, cellular senescence, and elevated osteoclastic activity in vitro and in vivo. Further, we reveal that our nanozyme is a previously unreported key regulator of osteoclast formation derived from macrophages while also directly targeting bone progenitor cells, favoring new bone formation despite its exposure to harmful levels of IR in vitro. These findings open a new approach for the specific prevention of IR-induced bone loss using synthesis-mediated designer multifunctional nanomaterials.

Impact of Docosahexaenoic acid supplementation on proinflammatory cytokines release and the development of Necrotizing enterocolitis in preterm Neonates: A randomized controlled study

INTRODUCTION

Preterm neonates have under-developed immune-regulatory system; consequently, there is a risk for developing chronic inflammation. Necrotizing enterocolitis (NEC) is an acute devastating neonatal intestinal inflammatory disorder. Due to the obscure multifactorial etiology, early diagnosis and effective treatment of NEC are limited. Consequently, effective strategies in the prevention of NEC, including nutritional approaches, are critically needed. The current study was conducted to assess the potential immunomodulatory effect of Docosahexaenoic Acid (DHA) supplementation in preterm neonates at neonatal intensive care unit (NICU) and subsequently its effect on preventing or reducing NEC incidence.

METHODS

This was a prospective randomized controlled study. A total of 67 neonates, with gestational age equal or less than 32 weeks at birth and weight less than or equal 1500 g, were randomly assigned to either DHA group or the control group. Modified Bell's staging criteria for NEC was used as an objective tool for diagnosis and staging of NEC. Levels of Interleukin 1 beta (IL-1β) were measured at baseline and after 10 days. Mortality and NICU length of stay (LOS) were also monitored.

RESULTS

Thirty neonates of each group completed the study. A statistically significant difference was observed between the two groups regarding diagnosis and staging of NEC (p = 0.0001). There was also a statistically significant difference between DHA group 22(73.3), 95% CI [55.9, 86.5] and the control group 8 (26.7), 95% CI [13.5, 44.1] in the percentage change in IL-1β levels (p = 0.0001).A statistically significant association was found between IL and 1 β change and NEC diagnosis (p = 0.001). NICU LOS was significantly lower among DHA group 21.63 ± 6.67 compared to the control group 25.07 ± 4.67 (p = 0.025). Mortality n (%) among the control group 4 (11.8) was higher than DHA group 3 (9.1), however, no significant difference was detected (p = 1.0).

CONCLUSION

Findings of this study suggest that enteral DHA supplementation can reduce NEC incidence in preterm neonates through its immunoregulatory effect that modulates production of regulatory cytokines.Trial registration: Registered at clinical trials.gov (NCT03700957), 6 October 2018.

Gingival crevicular fluid infiltrating CD14+ monocytes promote inflammation in periodontitis

Periodontitis is a condition that occurs because of inflammation-mediated tissue degeneration. Many studies have been conducted to identify inflammatory molecules in periodontitis, but the well-defined role of cells from the immune system in the progression of periodontitis as well as in gingival tissue degeneration has not been appropriately established. The objective of the present study was to characterize the monocytes isolated from the gingival crevicular fluid (GCF) in patients with periodontitis. GCF was obtained from periodontitis patients and healthy controls. Cytokine levels of CCL2 were evaluated by ELISA in GCF samples. CD14+ monocytes were separated using magnetic sorting from GCF. RT-qPCR was performed to assess the gene expression. Cytometric bead array analysis was performed to analyze the levels of cytokines and chemokines in the secretome of cells. CD14+ monocytes from GCF secreted higher levels of CCL2 and showed elevated expression of genes responsible for monocyte migration. Additionally, upon lipopolysaccharide stimulation, these monocytes secreted higher levels of inflammatory cytokines and chemokines. This investigation aids in understanding the inflammatory microenvironment of periodontitis by characterizing GCF in terms of infiltrated CD14+ monocytes, cytokines, and molecules secreted by these monocytes, which are specific for cellular differentiation.

Morin attenuates STZ-induced diabetic retinopathy in experimental animals

Diabetic retinopathy (DR) occurs in untreated diabetic patients due to the strong influence of oxidative stress. Bioflavonoids are well known for their antioxidant property. Morin, a bioflavonoid, has been demonstrated for its antioxidant as well as antidiabetic activity. Thus, this research work intended to determine the ameliorative impact of morin in DR rats using STZ-induced type 1 diabetic model. To induce type 1 diabetic in rats STZ (60 mg/kg) was administered intraperitoneally. Grouping of animals was done as described below (n = 6), where, group I - normal control, group II - diabetic control, group III - morin (25 mg/kg), group IV - morin (50 mg/kg), and group V - metformin (350 mg/kg) were used. All the animals underwent treatment for 60 days as given above. It was observed that supplementation of morin (25 and 50 mg/kg) showed a noteworthy decline in elevated serum glucose level. Moreover, decrease in the level of LPO and improved activity of endogenous antioxidants (GPx, CAT, and SOD) was observed in morin treated groups. It also notably drops the concentration of TNF-α, IL-1β, and VEGF in the tissue homogenate of the retina. Furthermore, it increased the retinal thickness and cell count in the ganglion cell layer of the retina in diabetic animals. Hence, we can conclude that morin encumbers the progression of DR in diabetic animals, which may be via antioxidant property and suppression of TNF-α, IL-1β, and VEGF.

Data describing expression of formyl peptide receptor 2 in human articular chondrocytes

The formyl peptide receptor 2 (FPR2) belongs to the family of seven-transmembrane G protein-coupled receptors (GPCR) and are expressed by many different cells but mainly studied in immune cells. FPR2 is involved in host defense against bacterial infections and clearance of damaged cells through the oxidative burst and chemotaxis of neutrophils. In addition, FPR2 has also been implicated as an immunomodulator in sterile inflammations, e.g. inflammatory joint diseases. Here we present data regarding FPR2 expression in human articular chondrocytes, isolated from healthy individuals and osteoarthritic patients, on both mRNA and protein level using qPCR and Imagestream flow cytometry. We also present data after receptor stimulation and monitoring of production of nitric oxide, reactive oxygen species, IL-6, IL-8 and MMP-3. The presented data show that human articular chondrocytes from patients with osteoarthritis as well as from healthy individuals express FPR2 both at mRNA and protein level. The biological relevance of FPR2 expression in chondrocytes needs to be further investigated.

Blood cells and endothelial barrier function

The barrier properties of endothelial cells are critical for the maintenance of water and protein balance between the intravascular and extravascular compartments. An impairment of endothelial barrier function has been implicated in the genesis and/or progression of a variety of pathological conditions, including pulmonary edema, ischemic stroke, neurodegenerative disorders, angioedema, sepsis and cancer. The altered barrier function in these conditions is often linked to the release of soluble mediators from resident cells (e.g., mast cells, macrophages) and/or recruited blood cells. The interaction of the mediators with receptors expressed on the surface of endothelial cells diminishes barrier function either by altering the expression of adhesive proteins in the inter-endothelial junctions, by altering the organization of the cytoskeleton, or both. Reactive oxygen species (ROS), proteolytic enzymes (e.g., matrix metalloproteinase, elastase), oncostatin M, and VEGF are part of a long list of mediators that have been implicated in endothelial barrier failure. In this review, we address the role of blood borne cells, including, neutrophils, lymphocytes, monocytes, and platelets, in the regulation of endothelial barrier function in health and disease. Attention is also devoted to new targets for therapeutic intervention in disease states with morbidity and mortality related to endothelial barrier dysfunction.