Antibody levels to Malassezia pachydermatis and Staphylococcus pseudintermedius in atopic dogs and their relationship with lesion scores.

BACKGROUND: Elevated immunoglobulin E (IgE) levels to Malassezia or Staphylococcus species in human atopic dermatitis are related to the skin severity index; a similar association has not been reported in atopic dogs. OBJECTIVES: To investigate serum levels of allergen-specific IgE, total specific IgG and IgG subclasses (IgG1 and IgG2) for M. pachydermatis and S. pseudintermedius, and to correlate them with the severity of dermatitis in dogs. ANIMALS: Serum samples were collected from dogs categorized by age and disease status. Groups 1 and 2: <3-year-old healthy (n = 9) and atopic dogs (n = 9), respectively; and groups 3 and 4: ≥3-year-old healthy (n = 11) and atopic dogs (n = 14), respectively. METHODS AND MATERIALS: Antibody levels were measured by ELISA. The Canine Atopic Dermatitis Lesion Index (CADLI) was analyzed in relation to antibody levels. RESULTS: Specific IgE and total IgG against M. pachydermatis and S. pseudintermedius were significantly increased in atopic dogs of all ages. Although differences between atopic and healthy dogs, with regard to specific IgG1 and IgG2 levels to each microbe, varied in significance within age groups. No significant relationships were found between the CADLI and any specific immunoglobulin levels for both microbe types. CONCLUSIONS AND CLINICAL IMPORTANCE: In dog skin, microbes may act as allergens triggering inflammatory responses via IgE- and IgG-dependent pathway(s). The affinity of the IgG subclass produced may vary according to antigen type. Specific IgE levels may be related to clinical disease in dogs and not to skin lesion severity.

Comparative proteomics reveals concordant and discordant biochemical effects of caffeine versus epigallocatechin-3-gallate in human endothelial cells.

Caffeine and epigallocatechin-3-gallate (EGCG) are the most abundant bioactive chemicals found in coffee and tea, respectively. While they are known to regulate normal physiology and body homeostasis, their biochemical effects, particularly at cellular and subcellular levels, remain under-investigated. We thus performed comparative proteomics study followed by bioinformatics analyses to investigate differential biochemical effects of these two chemicals on human endothelial cells. EA.hy926 cells were incubated with 100 µM caffeine or EGCG for 24-h and then subjected to label-free quantitative proteomics using nanoLC-ESI-Qq-TOF MS/MS compared to the control cells. A total of 142 and 152 significantly altered proteins were identified in caffeine-exposed and EGCG-exposed cells, respectively. Among these, 86 were the common changes found in both caffeine-exposed and EGCG-exposed cells. Bioinformatics revealed that both caffeine and EGCG mostly affected ribosomal proteins involving protein synthesis for membrane destination and secretion (e.g., SRP-dependent cotranslational protein targeting to membrane, protein targeting to endoplasmic reticulum, nuclear-transcribed mRNA catabolic process, nonsense-mediated decay, etc.). While the down-regulated proteins were similar in both groups, the up-regulated proteins in the EGCG-exposed cells highlighted the promoting effects of EGCG on actin-crosslink formation, glycolysis and ubiquitin-proteasome activity. These concordant and discordant changes in cellular proteome of human endothelial cells induced by caffeine and EGCG are useful for better understanding of biochemical/physiological effects of these two bioactive chemicals.

Quantitative proteomics reveals common and unique molecular mechanisms underlying beneficial effects of caffeine and trigonelline on human hepatocytes.

Caffeine and trigonelline are the major bioactive compounds in coffee. Caffeine alone or combined with other coffee compounds shows hepatoprotective effects. However, molecular mechanisms underlying such hepatoprotective effects remain unclear. We therefore addressed molecular effects of caffeine and trigonelline on human hepatocytes using quantitative proteomics followed by bioinformatic analyses to obtain topological and functional significance. HepG2 cells were treated with 100 µM caffeine or trigonelline for 24-h and evaluated by quantitative proteomics using nanoLC-ESI-LTQ-Orbitrap MS/MS. A total of 26 and 25 significantly altered proteins were identified in caffeine-treated and trigonelline-treated cells, respectively, compared with control cells. Topological analyses revealed that ribosomal and translation regulatory proteins predominantly served as the hub proteins associated with protein clusters. Functional analyses also revealed that these two bioactive compounds shared some molecular mechanisms via induction of translational processes. There were also other unique molecular functions and biological processes triggered or suppressed by either caffeine or trigonelline. These data highlight common and unique molecular mechanisms underlying the hepatoprotective effects of caffeine and trigonelline that may be useful for future clinical applications.

Hyaluronic acid promotes calcium oxalate crystal growth, crystal-cell adhesion, and crystal invasion through extracellular matrix.

Hyaluronic acid (HA), a macromolecule in glycosaminoglycans family, is normally excreted into the urine with a small amount, but with much greater level in the urine from stone patients (formers). However, its precise roles in kidney stone pathogenesis remained unclear. This study examined its roles in calcium oxalate (CaOx) kidney stone formation processes, including neocrystallization, crystal growth, adhesion, internalization, aggregation and invasion. The results showed that HA (1, 10, 100, 1000, or 10,000 ng/ml) did not affect CaOx neocrystallization, aggregation, and internalization into MDCK distal renal tubular cells. However, HA significantly promoted CaOx crystal growth (at 10-10,000 ng/ml), adhesion onto renal tubular cells (at 1000-10,000 ng/ml), and invasion through extracellular matrix (ECM) (at 1-10,000 ng/ml). Analysis of the plasminogen sequence revealed six sites with the HA-binding motif "B(X7)B" that explained the HA ability to trigger the plasminogen-plasmin system required for crystal invasion. In summary, our systematic analysis highlights the promoting effects of HA on CaOx crystal growth, crystal-cell adhesion and invasion through the ECM. These effects of HA may explain its high level in the stone patients' urine, thereby promoting the stone formation.

Cellular proteome datasets of human endothelial cells under physiologic state and after treatment with caffeine and epigallocatechin-3-gallate.

Human endothelial cells play several significant roles in vascular biology and homeostasis. We report herein cellular proteome datasets of EA.hy926 human endothelial cells under physiologic condition and after treatment with 100 µM caffeine or EGCG for 24-h. Cellular proteins were extracted and subjected to in-solution tryptic digestion using filter-aided sample preparation (FASP) method. The digested peptides were analyzed by nanoflow liquid chromatography coupled to tandem mass spectrometry (nanoLC-ESI-Qq-TOF MS/MS). Finally, the mass spectral data were searched against the human Swiss-Prot database using Mascot 2.4 search engine and quantified using Skyline v.3.5 software and BiblioSpec algorithm. All of these data were used for further comparative proteomics study followed by bioinformatics analyses to investigate differential biochemical effects of caffeine and EGCG on human endothelial cells (Chanthick et al., 2019) [1].

The prevalence of positive intradermal allergy tests in 114 dogs with atopic dermatitis in the Bangkok metropolis, Thailand.

Intradermal allergy tests using 47 selected local aero-allergens were performed on 114 dogs with atopic dermatitis. The subject animals visited the Dermatology Unit at the Veterinary Teaching Hospital of Kasetsart University or the SLV Pet Hospital with chronic pruritus and various skin lesions. Allergen extracts were composed of: 4 house dust and house dust mites, 7 household insects, 24 pollens, 11 mold spores, and Kapok. The prevalence of sensitization to various allergens were as follows: Dermatophagoides farinae (74.56%), Dermatophagoides pteronyssinus (53.51%), house dust (26.32%), American cockroach (Periplaneta americana) (23.68%), Para glass (21.93%) and mixed ants (20.18%). No relationship was noted between the various allergen groups and the location of the skin lesions except for those animals that reacted to pollens which appeared to have be more likely to have lesion affecting the perineum and tail area (p=0.022; OR, 6.429; 95% CI, 1.003-40.292).

Transcytosis Involvement in Transport System and Endothelial Permeability of Vascular Leakage during Dengue Virus Infection.

The major role of endothelial cells is to maintain homeostasis of vascular permeability and to preserve the integrity of vascular vessels to prevent fluid leakage. Properly functioning endothelial cells promote physiological balance and stability for blood circulation and fluid components. A monolayer of endothelial cells has the ability to regulate paracellular and transcellular pathways for transport proteins, solutes, and fluid. In addition to the paracellular pathway, the transcellular pathway is another route of endothelial permeability that mediates vascular permeability under physiologic conditions. The transcellular pathway was found to be associated with an assortment of disease pathogeneses. The clinical manifestation of severe dengue infection in humans is vascular leakage and hemorrhagic diatheses. This review explores and describes the transcellular pathway, which is an alternate route of vascular permeability during dengue infection that corresponds with the pathologic finding of intact tight junction. This pathway may be the route of albumin transport that causes endothelial dysfunction during dengue virus infection.

Caveolae-mediated albumin transcytosis is enhanced in dengue-infected human endothelial cells: A model of vascular leakage in dengue hemorrhagic fever.

Vascular leakage is a life-threatening complication of dengue virus (DENV) infection. Previously, association between "paracellular" endothelial hyperpermeability and plasma leakage had been extensively investigated. However, whether "transcellular" endothelial leakage is involved in dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) remained unknown. We thus investigated effects of DENV (serotype 2) infection on transcellular transport of albumin, the main oncotic plasma protein, through human endothelial cell monolayer by Western blotting, immunofluorescence staining, fluorescence imaging, and fluorometry. The data showed that Alexa488-conjugated bovine serum albumin (Alexa488-BSA) was detectable inside DENV2-infected cells and its level was progressively increased during 48-h post-infection. While paracellular transport could be excluded using FITC-conjugated dextran, Alexa488-BSA was progressively increased and decreased in lower and upper chambers of Transwell, respectively. Pretreatment with nystatin, an inhibitor of caveolae-dependent endocytic pathway, significantly decreased albumin internalization into the DENV2-infected cells, whereas inhibitors of other endocytic pathways showed no significant effects. Co-localization of the internalized Alexa488-BSA and caveolin-1 was also observed. Our findings indicate that DENV infection enhances caveolae-mediated albumin transcytosis through human endothelial cells that may ultimately induce plasma leakage from intravascular compartment. Further elucidation of this model in vivo may lead to effective prevention and better therapeutic outcome of DHF/DSS.