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Introduction: Methomyl (MET) is a carbamate insecticide, used in agriculture and public health to eliminate harmful insects. Besides its advantages in agriculture, it causes neurotoxic effects. The aim of this study was to evaluate the effect of MET on Spatial Working Memory (SWM), oxidative stress parameters, and histopathological changes in the hippocampus, as well as the possible protective role of Pelargonium graveolens Essential Oil (EO). Methods: Male Wistar rats were randomized into four groups of six animals: group I as the control that received the vehicle; group II received EO (75 mg/kg b.w), group III received MET (2 mg/kg b.w); and group IV received both MET and EO. The rats were administered the respective doses orally by gavage for 28 days. SWM was assessed using Y-maze on the day before the first treatment and day 28 after the last dose. They were sacrificed by decapitation and their brains were taken for assessing oxidative stress parameters and histopathological analysis. Results: MET treatment caused SWM deficits. Furthermore, drastic changes were observed in aspartate transaminase, alanine aminotransferase, and alkaline phosphatase activities. The level of malondialdehyde significantly increased, whereas antioxidant (glutathione-S-transferase and catalase) enzyme activities significantly decreased. The CA1 region of the hippocampus of rats exposed to MET revealed severe histological alterations. However, supplementation with EO improved SWM and partially restored the activities of antioxidant systems and prevented neuronal cell damage. Conclusion: P. graveolens EO has the potential in mitigating most of the adverse effects in the hippocampus and prevents SWM impairment induced by MET toxicity.

Awara (Astrocaryum vulgare M.) pulp oil has been shown to possess anti-inflammatory properties in vivo, and contains an unsaponifiable matter rich in bioactive compounds. This study focused on the ethanolic unsaponifiable fraction (EUF) of awara pulp oil. Its chemical composition has been characterized: carotenoid, phytosterol, and tocopherol contents represent 125.7, 152.6, and 6.8 μg/mg of EUF, respectively. We further evaluated this fraction for anti-inflammatory properties in J774 macrophages activated by lipopolysaccharide (LPS) plus interferon (IFN) γ to understand the biological effects of awara pulp oil. EUF strongly decreased nitric oxide (NO), prostaglandin E(2), tumour necrosis factor (TNF) α, and interleukin (IL) -6 and -10 production in activated J774 cells. Moreover, it inhibited expression of inducible NO synthase and cyclooxygenases-2 in vitro. The anti-inflammatory properties of EUF were also confirmed in vivo by modulation of TNFα, IL-6 and IL-10 serum concentration in an endotoxic shock model. Pre-treatment with awara oil fraction offers promise as a protective means to lower the production of excessive amounts of pro-inflammatory molecules. [ABSTRACT FROM AUTHOR]

Cystic echinococcosis (CE) is one of the most important zoonotic diseases with a worldwide distribution. It is caused by the larval stage of the dog tapeworm "Echinococcus granulosussensu lato" and constitutes a major economic and public health problem in several countries. Protoscoleces are one component of this larval stage that can interact with both definitive and intermediate hosts. The aim of the present study was to investigate the potential role of using a radio-attenuated form of these protoscoleces for immunoprophylaxis against experimental murine echinococcosis. However, mice were immunized twice at 15-day intervals with gamma (γ) irradiated protoscoleces at doses of 0.4, 0.8, 1.2 and 1.4 kGy then challenged with the intact parasites. Macroscopic and histological analyses with cytokine measurements were performed in order to estimate the number and diameter of cysts, microscopic changes and cytokine profile. An improvement in protection against the challenge dose was observed with increasing dose, giving percentages of 47.7, 49, 55.23 and 70.6%, for the 0.4, 0.8, 1.2 and 1.4 kGy-groups respectively. These data suggest that immunization with radio-attenuated protoscoleces may induce satisfactory protective immunity by reducing successfully the formation of cysts, caused by challenge infection., (© 2022 John Wiley & Sons Ltd.)

The aim of the present study was to estimate the potential toxic effects of a subacute and a subchronic exposure to methomyl (MET) on some parts of the digestive system in male albino rats. Wistar rats were exposed daily by oral gavage to 4 mg/kg body weight (b.w.) of MET over 28 days in subacute experiments and to 1 mg/kg b.w. of MET for 90 consecutive days in subchronic exposure. Plasma levels of liver function indicators (ALT, AST, ALP and LDH) were significantly elevated after administration of MET to rats. MET had significant pro-oxidative effects on the intestines, as indicated by decreases in nonenzymatic (GSH) and enzymatic antioxidant (GPx, GST and CAT) parameters and significant increases in TBARS levels in both the duodenum and colon of rats. Microscopically, the duodenum and colon of rats exposed to MET showed severe pathological changes. It could be concluded that MET profoundly altered the structure and antioxidant status of intestinal rat tissue, which might lead to intestinal and digestive dysfunctions.

Aims: To compare the bioactivity of circulating microparticles (MPs) isolated from dyslipidemic Psammomys obesus (P. obesus) fed a high-energy diet (HED) with those released from healthy P. obesus fed a normal diet (ND)., Methods: Vascular reactivity of aortic rings was evaluated by myography, after 24 h incubation in the absence or in the presence of circulating MPs isolated, by differential centrifugations, from the plasma of animals subjected to HED (MPs HED ) or ND (MPs ND ) for 12 weeks. Human umbilical vein endothelial cells (HUVECs) were treated for 24 h with MPs HED or MPs ND animals and subjected to immunofluorescence staining of caveolin-1 (cav-1), intercellular adhesion molecule-1 (ICAM-1), endothelial nitric oxide synthase (eNOS), F-actin and reactive oxygen species (ROS) detection., Results: The HED exerted a distinctly pronounced hyperlipidemic effect marked by plasmatic increase of total cholesterol, low-density lipoprotein-cholesterol (LDL-C) and triglyceride (TG). Both MPs ND and MPs HED induced a significant reduction of maximal relaxation induced by acetylcholine (ACh). Interestingly, MPs HED significantly decreased eNOS expression up to ~25% and increased ROS production up to ~75% on in vitro treated HUVECs. Moreover, in HUVECs, MPs HED significantly decreased cav-1 expression up to ~50% whereas significant increase of ICAM-1 expression by about 2-fold approximately was observed., Conclusion: Our experimental study demonstrated the dual role of MPs on vascular function by modulating endothelial cell function. Furthermore, MPs may be considered as vectors of a bioactive information contributing to inflammation and vascular damage., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Aims: To compare the effects of a high-energy diet (HED) with those of a low-energy diet (LED) on biochemical parameters, microparticle (MP) subpopulations and endothelial caveolin-1 (cav-1) protein expression in Psammomys obesus (P. obesus)., Methods: After 12weeks of feeding with either the HED or LED, fasting plasma glucose and lipid parameters were measured using an enzymatic colorimetric kit while serum insulin concentration was determined with radioimmunoassay kits. MP subpopulations and cav-1 protein expression were quantified using flow cytometry and western blot analysis, respectively., Results: We observed that the HED caused a marked increase in lipid parameters, even in normoglycemic P. obesus. The total number of circulating MPs and the numbers of platelet-, leukocyte-, and erythrocyte-derived MPs were unaltered in the HED group. However, the HED induced increases in the numbers of monocytes/neutrophils and procoagulant MPs and a decrease in the endothelial MP levels. Cav-1β protein expression and reactive oxygen species production were increased in the vascular endothelium of HED-treated P. obesus., Conclusion: From these findings, it is indicated that the HED exerts deleterious effects on the vascular system by increasing the monocyte/neutrophil and procoagulant MP levels, which may lead to cav-1β protein overexpression in dyslipidemic P. obesus., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Awara (Astrocaryum vulgare M.) is a palm fruit mainly used in nutrition. We analysed the pulp oil for fatty acid, tocopherol, carotenoid, and phytosterol and we evaluated whether this oil may attenuate inflammation in vivo. In an endotoxic shock model, awara pulp oil treatment decreased pro-inflammatory cytokines and increased anti-inflammatory cytokines. In a pulmonary inflammation model, awara pulp oil treatment reduced eosinophil and lymphocyte numbers recovered into the broncho-alveolar lavages. These results suggest that awara pulp oil administration can efficiently counteract an acute and chronic inflammatory response in vivo that is probably mediated by fatty acids and minor compounds., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Mannoproteins, as the main constituents of the outer layer of yeast cell walls, are able to interact with phagocytic cells in an opsonin-independent manner through the mannose receptor (MR) and to induce yeast ingestion by the professional phagocytes. Moreover, the MR also mediates endocytosis of soluble ligands through clathrin-coated pits. Here, we studied some aspects of the interaction between the MR and Candida albicans using murine E-clone macrophages and the consequences on MR trafficking. Using a pull-down assay involving mixture E-clone macrophage detergent lysate with mannosylated Sepharose beads and glutaraldehyde-fixed, heat-killed (HK) C. albicans, we found that binding of solubilized MR to mannosylated particles occurred with characteristics similar to the receptor's cell-surface mannose-binding activity. We then demonstrated that MR expressed on E-clone macrophages contributed to phagocytosis of unopsonized, HK C. albicans and that yeast phagocytosis induced a decrease in MR endocytic activity without concomitant degradation of the receptor in the time lapse studied.

Aspergillus fumigatus is a ubiquitous fungus that grows in decaying organic matter. It can cause disease in both immunodeficient and immunocompetent patients by using virulence factors to escape the host defenses. Some of these factors, such as a diffusate, released from the spores of A. fumigatus, have previously been described. This diffusate was demonstrated to inhibit oxidative burst and phagocytosis of coated red blood cells. The present study has shown that this substance can inhibit the phagocytosis of A. fumigatus spores by murine alveolar macrophages (MALU) and evaluated the action of this substance. We quantified phagocytosis by MALU cells with and without diffusate and evaluated the inhibition of phagocytosis by testing diffusates from different strains. We conclude that the spore diffusate of some strains of A. fumigatus can reversibly decrease the ability of alveolar macrophages to ingest A. fumigatus spores.

Our laboratory recently developed a light microscopy staining technique that provides a mean to distinguish between yeast that are simply bound to the surface of macrophages and yeast that have actually been phagocytized by macrophages (7). We adapted this technique by using fluorescent probes in order to test phagocytic activity by flow cytometry. Thus we are able to distinguish unambiguously extracellular from intracellular yeast during phagocytosis with the fast rate of flow cytometry (approximately 200 cells/s). The fluorescence quenching induced by a 1% tannic acid solution (w/v) can be applied to any FITC-labeled, heat-killed yeast cell or bacteria. The yeast cells already engulfed in the macrophage remain with their native fluorescence (internal and external pH equilibrated by 50 microM monensin 30 min/4 degrees C) protected from the action of tannic acid, a nonmembrane permeable molecule. The results presented here validate this new technique. An application is presented showing the inhibition of endocytosis by cytochalasin-B.

In the central nervous system, the functions of microglia appear crucial after brain damage, when phagocytes eliminate cell debris, acting as the scavengers of the brain. Diseases where an active role for microglia has been proposed recently include Alzheimer's disease, the acquired immune deficiency syndrome (AIDS) and multiple sclerosis. Only recently has it been possible to obtain a microglial cell line retaining morphological and functional aspects of these cells and their secretory products. Sugar receptors are expressed by a variety of phagocytes in primary cultures, but in contrast, are absent on the majority of the described macrophage-like cell lines. We here establish, by 4 degrees C binding experiments, that this murine cell line, called BV-2, expresses a high level (9.86 +/- 0.91 x 10(5); n = 3) of beta-glucan receptors. At 37 degrees C, BV-2 cells show high phagocytic power that can only be inhibited by the free polysugar beta-laminarin (a poly-glucose) and not by mannan (a poly-mannose) as described for macrophages. The beta-glucan receptor expressed by the microglial cell line BV-2 is fully functional in phagocytosis of unopsonized heat-killed yeast particles.

We studied the involvement of lectin-like receptors in phagocytosis of unopsonized heat-killed yeast (Saccharomyces cerevisiae) by murine macrophage-like cell lines and murine peritoneal resident macrophages. For this purpose we used a technique that allowed us to discriminate ingested and adsorbed heat-killed yeast. The internalization can be partly inhibited by soluble polyosides such as laminarin (beta-glucan) or alpha-mannan. However, when they were used together (0.4 mg/ml alpha-mannan and 0.4 mg/ml laminarin), almost complete inhibition of phagocytosis was obtained. These observations suggest that phagocytosis of unopsonized heat-killed yeast by murine macrophage-like cell lines as well as murine peritoneal resident macrophages is mediated by both mannose and beta-glucan receptors. The respective activity of these two types of receptors is a function of in vitro cell differentiation. To achieve maximal phagocytosis of unopsonized heat-killed yeast, coexpression of both mannose and beta-glucan receptors is required.

Murine macrophages isolated from the peritoneal cavity or from the lung were continuously grown and expanded in vitro on a confluent layer of "mesothelial or endothelial" feeding cells. These cell lines could be obtained from C57B16 or BalbC mice and were nontumorogenic in nude mice. The macrophages were characterized by their capacity to phagocytose yeasts and by the presence of nonspecific esterases, of Fc receptors, and of specific antigens (MAC1 ...). In vitro, these macrophages were fully activated and were tumoricidal against different tumor cell lines. In vivo, adoptive transfer of the expanded macrophages to mice bearing EMT6 sarcoma or 3LL metastasizing carcinoma inhibited the growth of the primary tumors and the development of metastases. Local injection in the vicinity of the primary tumor and i.v. transplantation were effective. The adoptive transfer of expanded macrophages could lead to a new kind of immunotherapy of neoplastic diseases combining selective amplification with effective activation of macrophages as key effector cells.