Endothelial Poldip2 regulates sepsis-induced lung injury via Rho pathway activation

Aims Sepsis-induced lung injury is associated with significant morbidity and mortality. Previously, we showed that heterozygous deletion of polymerase δ-interacting protein 2 (Poldip2) was protective against sepsis-induced lung injury. Since endothelial barrier disruption is thought to be the main mechanism of sepsis-induced lung injury, we sought to determine if the observed protection was specifically due to the effect of reduced endothelial Poldip2. Methods and results Endothelial-specific Poldip2 knock-out mice (EC−/−) and their wild-type littermates (EC+/+) were injected with saline or lipopolysaccharide (18 mg/kg) to model sepsis-induced lung injury. At 18 h post-injection mice, were euthanized and bronchoalveolar lavage (BAL) fluid and lung tissue were collected to assess leucocyte infiltration. Poldip2 EC−/− mice showed reduced lung leucocyte infiltration in BAL (0.21 ± 0.9×106 vs. 1.29 ± 1.8×106 cells/mL) and lung tissue (12.7 ± 1.8 vs. 23 ± 3.7% neutrophils of total number of cells) compared to Poldip2 EC+/+ mice. qPCR analysis of the lung tissue revealed a significantly dampened induction of inflammatory gene expression (TNFα 2.23 ± 0.39 vs. 4.15 ± 0.5-fold, IκBα 4.32 ± 1.53 vs. 8.97 ± 1.59-fold), neutrophil chemoattractant gene expression (CXCL1 68.8 ± 29.6 vs. 147 ± 25.7-fold, CXCL2 65 ± 25.6 vs. 215 ± 27.3-fold) and a marker of endothelial activation (VCAM1 1.25 ± 0.25 vs. 3.8 ± 0.38-fold) in Poldip2 EC−/− compared to Poldip2 EC+/+ lungs. An in vitro model using human pulmonary microvascular endothelial cells was used to assess the effect of Poldip2 knock-down on endothelial activation and permeability. TNFα-induced endothelial permeability and VE-cadherin disruption were significantly reduced with siRNA-mediated knock-down of Poldip2 (5 ± 0.5 vs. 17.5 ± 3-fold for permeability, 1.5 ± 0.4 vs. 10.9 ± 1.3-fold for proportion of disrupted VE-cadherin). Poldip2 knock-down altered expression of Rho-GTPase-related genes, which correlated with reduced RhoA activation by TNFα (0.94 ± 0.05 vs. 1.29 ± 0.01 of relative RhoA activity) accompanied by redistribution of active-RhoA staining to the centre of the cell. Conclusion Poldip2 is a potent regulator of endothelial dysfunction during sepsis-induced lung injury, and its endothelium-specific inhibition may provide clinical benefit.

Beneficial effects of ROCEN (Topical Nano-arthrocen) on atopic dermatitis in mice

Objective Atopic dermatitis (AD) is a chronic inflammatory skin disease mainly caused by immune stimuli. The current study was conducted to investigate the effects of ROCEN and to compare it with betamethasone (Beta) on mice subjected to AD. Methods First, the safety of topical ROCEN was tested to determine possible sensitization induction in vivo. Then, the mice were subjected to oxazolone (Oxa) to induce chronic AD. Consequently, they underwent treatment with ROCEN and Beta. Scratching and wiping behaviors related to dermatitis were evaluated in treated animals for 35 days. The histopathology and immunohistochemistry (IHC) analysis of interleukin-8 (IL-8) and tumor necrosis factor-α (TNF-α) cytokines were performed on the dorsal skin of the treated mice. Results Topical administration of ROCEN and Beta to the dorsum of sensitized mice for 5 weeks significantly alleviated scratching and wiping symptoms and reduced erythema, scaling, and edema in the skin of the mice with AD. Moreover, histological indices showed that ROCEN effectively reduced leucocyte infiltration and improved skin healing parameters in treated AD mice. Application of ROCEN or Beta reduced IHC markers including IL-8 and TNF-α significantly. Conclusion ROCEN alleviated the AD symptoms similar to betamethasone in an experimental animal model.

Dengue virus infection induces inflammation and oxidative stress on the heart

ObjectiveDengue fever is one of the most important arboviral diseases in the world, and its severe forms are characterised by a broad spectrum of systemic and cardiovascular hallmarks. However, much remains to be elucidated regarding the pathogenesis triggered by Dengue virus (DENV) in the heart. Herein, we evaluated the cardiac outcomes unleashed by DENV infection and the possible mechanisms associated with these effects.MethodsA model of an adapted DENV-3 strain was used to infect male BALB/c mice to assess haemodynamic measurements and the functional, electrophysiological, inflammatory and oxidative parameters in the heart.ResultsDENV-3 infection resulted in increased systemic inflammation and vascular permeability with consequent reduction of systolic blood pressure and increase in heart rate. These changes were accompanied by a decrease in the cardiac output and stroke volume, with a reduction trend in the left ventricular end-systolic and end-diastolic diameters and volumes. Also, there was a reduction trend in the calcium current density in the ventricular cardiomyocytes of DENV-3 infected mice. Indeed, DENV-3 infection led to leucocyte infiltration and production of inflammatory mediators in the heart, causing pericarditis and myocarditis. Moreover, increased reactive oxygen species generation and lipoperoxidation were also verified in the cardiac tissue of DENV-3 infected mice.ConclusionsDENV-3 infection induced a marked cardiac dysfunction, which may be associated with inflammation, oxidative stress and electrophysiological changes in the heart. These findings provide new cardiac insights into the mechanisms involved in the pathogenesis triggered by DENV, contributing to the research of new therapeutic targets for clinical practice.

In vivo toxicities of the hospital effluent in Mahdia Tunisia

Hospital effluent (HE) is one of the most important sources of pharmaceutical released into the environment. This kind of pollution is a recognized problem for both human health and aquatic life. Consequently, in the present study, we assessed the effects of hospital untreated effluent on mice via biochemical and histopathological determinations. Female mice were given free access to water bottles containing untreated HE at different dilutions for 21 days. Then clinical biochemistry and histopathology evaluation were conducted. Serum biochemistry analysis showed the presence of significant increase in cholesterol, triglycerides, glycaemia and total bilirubin. However, phosphatase alkaline and urea activities have been significantly decreased compared to the control group. No significant variation was observed for the rest of the studied parameters (high-density lipoproteins; low-density lipoproteins and uric acid). Additionally, multiple alterations, including cellular necrosis, leucocyte infiltration and congestion, were observed in different tissues of mice exposed to the tested HE.

Probiotic Lactobacillus kefiri prevents endotoxin-induced preterm birth and stillbirth in mice

Preterm birth (PTB), defined as birth occurring before 37 weeks of pregnancy, affects 5-18% of pregnancies and is the leading cause of neonatal morbidity and mortality worldwide. Although PTB is considered a syndrome, infection-induced inflammation accounts up to 50% of all cases. Despite the effort to reduce the incidence of PTB, it continues rising worldwide and current approaches for preventing or treating PTB are largely unsatisfactory. Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. It is well known that probiotics can modulate the host immune system exerting a potent anti-inflammatory activity. The main aim of this work was to evaluate the capacity of the probiotic Lactobacillus kefiri (Lk48) to prevent preterm birth in mice. C57BL/6 female mice were treated with Lk48 or vehicle a week before and during pregnancy and were challenged with LPS (10 µg), a dose known to induce 100% of PTB, on gestational day 16. Percentages of PTB as well as stillbirth were evaluated. We observed that oral administration of Lk48 significantly reduced the occurrence of LPS-induced PTB and stillbirth as well as improved post-natal development. This protective effect was associated with a reduction in leucocyte infiltration and reduced inflammation-induced damage in reproductive tissue. Besides, Lk48 treatment also modulated the diversity of vaginal microbiota. Our results demonstrated that prophylactic consumption of probiotic Lactobacillus kefiri prevented LPS-induced PTB and still birth in mice and open new avenues for exploring novel and promising strategies for preventing PTB in humans.

Beneficial Effects of Liposome Containing Arthrocen (ROCEN)) on Atopic Dermatitis in Mice

Objective: Atopic dermatitis (AD) is a chronic inflammatory skin disease caused mainly by the immune stimulus. The current study aimed to investigate the effects of liposome containing arthrocen (ROCEN) and its comparison with betamethasone (Beta) on mice subjected to AD. Methods: First of all, the risk assessment of ROCEN sensitization was done, then mice were subjected to oxazolone (Oxa) for chronic AD induction and treatment. Scratching and wiping behaviors related to dermatitis were evaluated in animals treated topically with ROCEN. The histological and immunohistochemistry analysis of interleukin-8 (IL-8) and tumor necrosis factor-α (TNF-α) were conducted to the dorsal skin of treated rats. Results: The results showed that cutaneous administration of ROCEN on sensitized mice for 5 weeks, alleviated significantly scratching and wiping symptoms, erythema, scaling, and edema in animals’ skin. Moreover, histological indices showed that ROCEN reduced effectively leucocyte infiltration and improved skin healing parameters in AD mice. Immunohistochemically markers of IL-8 and TNF-α were hindered significantly by ROCEN in dermal tissues of mice. Conclusion: ROCEN potentiated alleviation of the AD symptoms rather than betamethasone drug in an experimental model.

Role of placental inflammatory mediators and growth factors in patients with rheumatic diseases with a focus on systemic sclerosis

Objectives Pregnancy in SSc is burdened with an increased risk of obstetric complications. Little is known about the underlying placental alterations. This study aimed to better understand pathological changes and the role of inflammation in SSc placentas. Leucocyte infiltration, inflammatory mediators and atypical chemokine receptor 2 (ACKR2) expression in SSc placentas were compared with those in other rheumatic diseases (ORD) and healthy controls (HC). Methods A case–control study was conducted on eight pregnant SSc patients compared with 16 patients with ORD and 16 HC matched for gestational age. Clinical data were collected. Placentas were obtained for histopathological analysis and immunohistochemistry (CD3, CD20, CD11c, CD68, ACKR2). Samples from four SSc, eight ORD and eight HC were analysed by qPCR for ACKR2 expression and by multiplex assay for cytokines, chemokines and growth factors involved in angiogenesis and inflammation. Results The number of placental CD3, CD68 and CD11 cells was significantly higher in patients affected by rheumatic diseases (SSc+ORD) compared with HC. Hepatocyte growth factor was significantly increased in the group of rheumatic diseases patients (SSc+ORD) compared with HC, while chemokine (C-C motif) ligand 5 (CCL5) was significantly higher in SSc patients compared with ORD and HC. CCL5 levels directly correlated with the number of all local inflammatory cells and higher levels were associated with histological villitis. Conclusions Inflammatory alterations characterize placentas from rheumatic disease patients and could predispose to obstetric complications in these subjects.

The Potential Impacts of Soy Protein on Fish Gut Health

Soy protein is the major source of protein as fishmeal replacement in fish feed because of its worldwide availability and low price. However, the presence of high carbohydrate content along with saponins, lectins, and phytates can have a negative impact on fish gut health. Based on the literature and our lab studies, dietary soybean meal can cause a dose-dependent type of distal intestine inflammation called enteritis in commercial fish species including salmonids. This leads to reduced absorptive capacity, increased mucus secretion, hyperpermeability, and leucocyte infiltration in the lamina propria and submucosa, also inducing the pro-inflammatory cytokine genes expression, including Il-1β, Il-8, and Tnf-α. In addition, dietary soy may alter the composition and population of the gut microbiota via providing nutrients and energy that preferentially support the growth of some gut bacteria. This chapter summarizes the current knowledge of the effects of soy protein on the enteritis and gut microbiota.

Local steroid activation is a critical mediator of the anti-inflammatory actions of therapeutic glucocorticoids

ObjectivesThe enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) plays a well-characterised role in the metabolism and activation of endogenous glucocorticoids (GCs). However, despite its potent upregulation at sites of inflammation, its role in peripheral metabolism and action of therapeutic GCs remains poorly understood. We investigated the contribution of 11β-HSD1 to the anti-inflammatory properties of the active GC corticosterone, administered at therapeutic doses in murine models of polyarthritis.MethodsUsing the tumour necrosis factor-tg and K/BxN serum-induced models of polyarthritis, we examined the anti-inflammatory properties of oral administration of corticosterone in animals with global, myeloid and mesenchymal targeted transgenic deletion of 11β-HSD1. Disease activity and joint inflammation were scored daily. Joint destruction and measures of local and systemic inflammation were determined by histology, micro-CT, quantitative RT-PCR, fluorescence activated cell sorting and ELISA.ResultsGlobal deletion of 11β-HSD1 resulted in a profound GC resistance in animals receiving corticosterone, characterised by persistent synovitis, joint destruction and inflammatory leucocyte infiltration. This was partially reproduced with myeloid, but not mesenchymal 11β-HSD1 deletion, where paracrine GC signalling between cell populations was shown to overcome targeted deletion of 11β-HSD1.ConclusionsWe identify an entirely novel component of therapeutic GC action, whereby following their systemic metabolism, they require peripheral reactivation and amplification by 11β-HSD1 at sites of inflammation to deliver their anti-inflammatory therapeutic effects. This study provides a novel mechanistic understanding of the anti-inflammatory properties of therapeutic GCs and their targeting to sites of inflammation in polyarthritis.