Valproic acid inhibits chronic Toxoplasma infection and associated brain inflammation in mice

Author(s):  
Marjan Enshaeieh ◽  
Geita Saadatnia ◽  
Jalal Babaie ◽  
Majid Golkar ◽  
Samira Choopani ◽  
...  

Individuals infected with Toxoplasma gondii ( T. gondii ) are prone to psycho-behavioral disorders, most notably schizophrenia and bipolar. Valproic acid reportedly inhibited the proliferation of T. gondii tachyzoites in vitro. However, animals treated with the drug neither lived longer during acute infection nor had fewer brain cysts upon chronic infection. In this study, a quantitative real-time PCR (qPCR) method was applied to quantify copy numbers of BAG1 (a bradyzoite-specific protein), REP529 DNA (a repetitive DNA fragment of the parasite), and SAG1 (a highly expressed tachyzoite-specific surface protein) in brains of chronically infected mice treated by valproic acid. The treatment inhibited the infection and decreased BAG1, SAG1, and REP529 copy numbers in mice brains ( P < 0.0001 ), comparable to Trimethoprim/Sulfamethoxazole (TMP/SMZ), the common medication for Toxoplasmosis treatment. Moreover, valproic acid decreased brain TNF-α expression ( P < 0.0001 ), comparable to TMP/SMZ. Histological examination of mice brains showed a marked reduction in cyst establishment, perivascular infiltration of lymphocytes, and glial nodules to the same level as the TMP/SMZ group. Our results provide direct evidence for the efficacy of valproic acid, a mood-stabilizing and antipsychotic drug against chronic Toxoplasma infection. These results might help modulate therapeutic regimens for neuropsychiatric patients and design more effective anti- Toxoplasma drugs.

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Marisol Pérez-Acosta ◽  
Félix Giovanni Delgado ◽  
Jaime E. Castellanos

Dengue virus (DENV) produces an acute infection that results in the overproduction of proinflammatory cytokines. Although increased levels of the immunoregulator soluble ST2 (sST2) protein have been reported in the serum of patients with dengue, its importance during DENV infection remains unclear. The purpose of this study was to evaluate the effect of a recombinant human sST2 protein on the production of TNF-α and IL-6 in an in vitro model of DENV infection. Peripheral blood mononuclear cells (PBMCs) were permissive to in vitro DENV infection since viral antigen was detected in CD14+ monocytes by flow cytometry (median, 1%; range, 0–2.2), and in their supernatants TNF-α and IL-6 were detected. However, sST2 protein was not detected. Using multiple staining on infected PBMC we found that only CD14+ cells produced TNF-α and IL-6. Treatment with human recombinant sST2 protein decreased lipopolysaccharide-induced monocyte TNF-α and IL-6 production. However, this effect was not observed when the monocytes were pretreated with sST2 and later infected with DENV-2. These results suggest that sST2 has different roles in the regulation of TNF-α and IL-6 expression in human monocytes stimulated with LPS and DENV-2.


2008 ◽  
Vol 294 (4) ◽  
pp. E654-E667 ◽  
Author(s):  
Ji Young Kim ◽  
Kun Liu ◽  
Shengli Zhou ◽  
Kristin Tillison ◽  
Yu Wu ◽  
...  

Fat-specific protein 27 (FSP27)/CIDEC was initially identified by its upregulation in TA1 adipogenesis and is one of three cell death-inducing DFF45-like effector (CIDE) family proapoptotic proteins. Ectopic expression of CIDEs promotes apoptosis of mammalian cells. On the other hand, FSP27 has very recently been illustrated to regulate lipid droplet size and promote lipid storage in adipocytes. Regulation of endogenous FSP27 expression is unknown. We assessed the FSP27 transcript level in the well-characterized 3T3-L1 in vitro adipocyte differentiation model and found its emergence parallels the adipocyte-enriched transcript adipocyte fatty acid binding protein and stearoyl Co-A desaturase 1. Furthermore, FSP27 is a differentiation-dependent transcript in adipogenesis of primary rodent and human preadipocytes and in brown adipogenesis. The FSP27 transcript is inversely regulated by TNF-α and insulin, consistent with an antilipolytic function. It is nearly abolished with a 4-h exposure of 3T3-L1 adipocytes to 10 ng/ml TNF-α, while treatment with 100 nM insulin increased the FSP27 transcript eightfold. In the latter case LY-294002 blocked this response, indicating involvement of phosphatidylinositol 3-kinase signals. Northern blot analysis of murine tissues indicated exclusive expression of FSP27 in white and brown adipose tissue; however, a dramatic upregulation occurred in the liver of ob/ob mice. Ectopic expression of murine FSP27 in 293T cells and in 3T3-L1 preadipocytes led to the appearance of key apoptotic hallmarks and cell death. However, despite the upregulation for FSP27 in adipogenesis, we failed to detect DNA laddering indicative of apoptosis in 3T3-L1 adipocytes. This suggests that adipogenesis is accompanied by decreased susceptibility to the proapoptotic effects of FSP27. Overall, our findings support roles for FSP27 in cell death and in adipocyte function.


2021 ◽  
Author(s):  
Adrian R Kendal ◽  
Antonina Lach ◽  
Pierre-Alexis Mouthuy ◽  
Richard Brown ◽  
Constantinos Loizou ◽  
...  

Chronic tendinopathy represents a growing burden to healthcare services in an active and ageing global population. The ability to identify, isolate and interrogate, in vitro, key pathogenic and reparative tendon cell populations is essential to developing precision therapies and implantable materials. Human hamstring tendon cells were cultured for 8 days on either tissue culture plastic or aligned electrospun fibres made of polydioxanone (absorbable polymer). Combined single cell surface proteomics and unbiased single cell transcriptomics (CITE-Seq) revealed six discrete cell clusters, four of which shared key gene expression determinants with ex vivo human cell clusters. These were PTX3_PAPPA, POST_SCX, DCN_LUM and ITGA7_NES cell clusters. Surface proteomics found that PTX3_PAPPA cells were CD10+CD26+CD54+. ITGA7_NES cells were CD146+, and POSTN_SCX cells were CD90+CD95+CD10+. Three clusters preferentially survived and proliferated on the aligned electrospun fibres; DCN_LUM, POSTN_SCX, and PTX3_PAPPA. They maintained high expression of tendon matrix associated genes, including COL1A1, COL1A2, COL3A1, ELN, FBLN1, and up-regulated genesets enriched for TNF-α signalling via NFκB, IFN-γ signalling and IL-6/STAT3 signalling. When cells were pre-selected based on surface protein markers, a similar up-regulation of pro-inflammatory signalling pathways was observed, particularly in PTX3 gene expressing CD10+CD26+CD54+ cells, with increased expression of genes associated with TNF-α signalling and IFN-γ signalling. Discrete human tendon cell sub populations persist in vitro culture and can be recognised by specific gene and surface protein signatures. Aligned PDO fibres promote the survival of three clusters, including pro-inflammatory PTX3 expressing CD10+CD26+CD54+ cells found in chronic tendon disease.


2010 ◽  
Vol 7 (1) ◽  
pp. 30 ◽  
Author(s):  
Henrik Wilms ◽  
Jobst Sievers ◽  
Uta Rickert ◽  
Martin Rostami-Yazdi ◽  
Ulrich Mrowietz ◽  
...  

2013 ◽  
Vol 304 (9) ◽  
pp. C895-C904 ◽  
Author(s):  
Mokarram Hossain ◽  
Syed M. Qadri ◽  
Yang Su ◽  
Lixin Liu

Leukocyte-endothelial interaction triggers signaling events in endothelial cells prior to transendothelial migration of leukocytes. Leukocyte-specific protein 1 (LSP1), expressed in endothelial cells, plays a pivotal role in regulating subsequent recruitment steps following leukocyte adhesion. In neutrophils, LSP1 is activated by phosphorylation of its serine residues by molecules downstream of p38 MAPK and PKC. Whether leukocyte adhesion to endothelial cells is required for endothelial LSP1 activation remains elusive. In addition, discrepancies in the functions of endothelial and leukocyte LSP1 in leukocyte adhesion prevail. We demonstrate that adhesion of wild-type ( Lsp1+/+) neutrophils to LSP1-deficient ( Lsp1−/−) endothelial cells was significantly reduced compared with adhesion to Lsp1+/+endothelial cells. Immunoblotting revealed increased phosphorylated endothelial LSP1 in the presence of adherent Lsp1−/−neutrophils [stimulated by macrophage inflammatory protein-2 (CXCL2), TNF-α, or thapsigargin], but not cytokine or chemokine alone. Pharmacological inhibition of p38 MAPK by SB-203580 (10 μM) significantly blunted the phosphorylation of endothelial LSP1. Functionally blocking endothelial ICAM-1 or neutrophil β2-integrins diminished neutrophil adhesion and phosphorylation of endothelial LSP1. The engagement of endothelial ICAM-1 cross-linking, which mimics leukocyte adhesion, resulted in phosphorylation of endothelial LSP1. In neutrophil-depleted Lsp1+/+mice, administration of ICAM-1 cross-linking antibody resulted in increased phosphorylation of LSP1 and p38 MAPK in TNF-α-stimulated cremaster muscle. In conclusion, endothelial LSP1 participates in leukocyte adhesion in vitro, and leukocyte adhesion through ICAM-1 fosters the activation of endothelial LSP1, an effect at least partially mediated by the activation of p38 MAPK. Endothelial LSP1, in contrast to neutrophil LSP1, is not phosphorylated by cytokine or chemokine stimulation alone.


Author(s):  
U. Aebi ◽  
L.E. Buhle ◽  
W.E. Fowler

Many important supramolecular structures such as filaments, microtubules, virus capsids and certain membrane proteins and bacterial cell walls exist as ordered polymers or two-dimensional crystalline arrays in vivo. In several instances it has been possible to induce soluble proteins to form ordered polymers or two-dimensional crystalline arrays in vitro. In both cases a combination of electron microscopy of negatively stained specimens with analog or digital image processing techniques has proven extremely useful for elucidating the molecular and supramolecular organization of the constituent proteins. However from the reconstructed stain exclusion patterns it is often difficult to identify distinct stain excluding regions with specific protein subunits. To this end it has been demonstrated that in some cases this ambiguity can be resolved by a combination of stoichiometric labeling of the ordered structures with subunit-specific antibody fragments (e.g. Fab) and image processing of the electron micrographs recorded from labeled and unlabeled structures.


2006 ◽  
Vol 175 (4S) ◽  
pp. 257-257
Author(s):  
Jennifer Sung ◽  
Qinghua Xia ◽  
Wasim Chowdhury ◽  
Shabana Shabbeer ◽  
Michael Carducci ◽  
...  

2012 ◽  
Vol 50 (08) ◽  
Author(s):  
M Gluth ◽  
C Weber ◽  
H Mukai ◽  
D Baumgart ◽  
J Turner ◽  
...  
Keyword(s):  

1971 ◽  
Vol 68 (1_Suppl) ◽  
pp. S223-S246 ◽  
Author(s):  
C. R. Wira ◽  
H. Rochefort ◽  
E. E. Baulieu

ABSTRACT The definition of a RECEPTOR* in terms of a receptive site, an executive site and a coupling mechanism, is followed by a general consideration of four binding criteria, which include hormone specificity, tissue specificity, high affinity and saturation, essential for distinguishing between specific and nonspecific binding. Experimental approaches are proposed for choosing an experimental system (either organized or soluble) and detecting the presence of protein binding sites. Techniques are then presented for evaluating the specific protein binding sites (receptors) in terms of the four criteria. This is followed by a brief consideration of how receptors may be located in cells and characterized when extracted. Finally various examples of oestrogen, androgen, progestagen, glucocorticoid and mineralocorticoid binding to their respective target tissues are presented, to illustrate how researchers have identified specific corticoid and mineralocorticoid binding in their respective target tissue receptors.


2020 ◽  
Vol 20 (15) ◽  
pp. 1857-1872
Author(s):  
Alberto M. Muñoz ◽  
Manuel J. Fragoso-Vázquez ◽  
Berenice P. Martel ◽  
Alma Chávez-Blanco ◽  
Alfonso Dueñas-González ◽  
...  

Background: Our research group has developed some Valproic Acid (VPA) derivatives employed as anti-proliferative compounds targeting the HDAC8 enzyme. However, some of these compounds are poorly soluble in water. Objective: Employed the four generations of Polyamidoamine (G4 PAMAM) dendrimers as drug carriers of these compounds to increase their water solubility for further in vitro evaluation. Methods: VPA derivatives were subjected to Docking and Molecular Dynamics (MD) simulations to evaluate their affinity on G4 PAMAM. Then, HPLC-UV/VIS, 1H NMR, MALDI-TOF and atomic force microscopy were employed to establish the formation of the drug-G4 PAMAM complexes. Results: The docking results showed that the amide groups of VPA derivatives make polar interactions with G4 PAMAM, whereas MD simulations corroborated the stability of the complexes. HPLC UV/VIS experiments showed an increase in the drug water solubility which was found to be directly proportional to the amount of G4 PAMAM. 1H NMR showed a disappearance of the proton amine group signals, correlating with docking results. MALDI-TOF and atomic force microscopy suggested the drug-G4 PAMAM dendrimer complexes formation. Discussion: In vitro studies showed that G4 PAMAM has toxicity in the micromolar concentration in MDAMB- 231, MCF7, and 3T3-L1 cell lines. VPA CF-G4 PAMAM dendrimer complex showed anti-proliferative properties in the micromolar concentration in MCF-7 and 3T3-L1, and in the milimolar concentration in MDAMB- 231, whereas VPA MF-G4 PAMAM dendrimer complex didn’t show effects on the three cell lines employed. Conclusion: These results demonstrate that G4 PAMAM dendrimers are capableof transporting poorly watersoluble aryl-VPA derivate compounds to increase its cytotoxic activity against neoplastic cell lines.


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