Usnic Acid Potassium Salt: Evaluation of the Acute Toxicity and Antinociceptive Effect in Murine Model.

To obtain usnic acid potassium salt (PS-UA), the usnic acid (UA) was extracted and purified from the lichen Cladonia substellata, and modified to produce PS-UA. The structure was determined by 1H-NMR, IR and elemental analysis, ratified through computational models, as well as identification the site of K+ insertion in the molecule. Antinociceptive activity was detected through contortions in mice induced by acetic acid and formalin (phases I and II) after treatments with 10 and 20 mg/kg of PS-UA, indicating interference in both non-inflammatory and inflammatory pain. After oral administration at doses of 500, 1000 and 2000 mg/kg, no deaths of mice with treatments below 2000 mg/kg were observed. Except for body weight gain, food and water consumption decreased with treatments of 1000 and 2000 mg/kg, and the number of segmented leukocytes was higher for both treatments. Regarding serum levels, cholesterol and triglycerides decreased, however, there was an increase in hepatic transaminases with both treatments. Liver and kidney histological changes were detected in treatments of 2000 mg/kg, while the spleen was preserved. The PS-UA demonstrated antinociceptive activity while the acute toxicity at the concentration of 2000 mg/kg was the only dose that presented morphological changes in the liver and kidney.

Immunomodulation of liver injury by Ascaris suum extract in an experimental model of autoimmune hepatitis.

Adult worm extract from Ascaris suum (Asc) has immunosuppressive activity and elicits Th2/IL-4/IL-10 response. This study evaluated the prophylactic and therapeutic effect of Asc in a murine model of concanavalin A (ConA)-induced autoimmune hepatitis (AIH). BALB/c mice received ConA, iv, (20 mg/kg), and three groups of animals were formed: (1) AIH, received only ConA; (2) AIH + Asc prophylactic, treated with Asc (1 mg/ml), ip, 30 min before of the AIH; and (3) AIH + Asc therapeutic, treated with Asc 2 h after the AIH. Plasma transaminase and immunoglobulins (measured at 8 and 24 h and 7 days after treatment) and cytokine production (IL-4, IL-10, IL-13, and IFN-γ) by splenocytes upon ConA and Asc stimulus were compared. The livers were weighed and examined histologically. In the AIH group, there was an increase in liver weight, transaminase levels, and total immunoglobulins. These parameters were reduced by 8-24 h and 7 days in the prophylactic group, but in the therapeutic group, only on day 7. The survival rate of mice in the AIH group was 38.5%, compared to 67% in the therapeutic Asc group. The survival rate of the animals with AIH that were prophylactically treated with Asc was 100%. A decrease of cellular infiltration and high levels of IL-4, IL-10, and IL-13 were induced by Asc. An increase of liver fibrosis was also observed, but with less intensity with prophylactic treatment. Thus, the Ascaris components have an inhibitory effect on AIH, with an intense Th2 immune response.

Carbohydrate profiling of fungal cell wall surface glycoconjugates of Aspergillus species in brain and lung tissues using lectin histochemistry.

The aim of this study was to evaluate, through lectin histochemistry, the expression of N-acetyl-D-glucosamine, L-fucose, D-galactose and glucose/mannose on the cell wall surfaces of Aspergillus species in histopathological specimens of brain (n = 1) and lung (n = 6) tissues obtained during autopsy of patients diagnosed postmortem as having had invasive aspergillosis. Concanavalin A (Con A), wheat germ agglutinin (WGA), Ulex europeus agglutinin I (UEA-I) and peanut agglutinin (PNA), all conjugated with horseradish peroxidase, were employed. Lectin-binding was visualized using 3,3-diaminobendizine (DAB) and hydrogen peroxide in phosphate buffer solution (PBS). We observed expression of N-acetyl-D-glucosamine and methyl-α-D-mannoside on the cell wall surfaces of all evaluated Aspergillus species, while the expression of L-fucose and D-galactose demonstrated inter and intra-specific variations. The results obtained from this study indicate that the use of WGA and Con A lectins permits visualization of Aspergillus structures such as hyphae, conidial heads and conidia in histopathological specimens of brain and lung tissues.

Lectin staining patterns in human gastric mucosae with and without exposure to Helicobacter pylori.

The aim of the present study was to evaluate qualitative changes in the glycoconjugate expression in human gastric tissue of positive and negative patients for Helicobacter pylori, through lectins: Wheat Germ Agglutinin (WGA) and Concanavalin A (Con A). The lectins recognized differently the glycoconjugates in the superficial mucous layer at the gastric tissues. The results suggest a significant change in the carbohydrate moieties present on the surface of the gastric cells during infection.

Lectin staining patterns in human gastric mucosae with and without exposure to Helicobacter pylori / Padrões de ligação de lectinas em mucosa gástrica humana com e sem exposição a Helicobacter pylori

The aim of the present study was to evaluate qualitative changes in the glycoconjugate expression in human gastric tissue of positive and negative patients for Helicobacter pylori, through lectins: Wheat Germ Agglutinin (WGA) and Concanavalin A (Con A). The lectins recognized differently the glycoconjugates in the superficial mucous layer at the gastric tissues. The results suggest a significant change in the carbohydrate moieties present on the surface of the gastric cells during infection.

O objetivo do presente estudo foi avaliar as mudanças qualitativas na expressão de glicoconjugados em tecidos gástrico humano de pacientes infectados ou não pelo Helicobacter pylori, através das lectinas: Wheat germ agglutinin (WGA) e Concanavalina A (Con A). As lectinas reconheceram diferentemente os glicoconjugados nas camadas mucosas superficiais do tecido gástrico. Os resultados sugerem mudanças significantes nas porções de carboidratos presentes nas células gástricas durante a infecção.

Altered lectin-binding sites in normal colon and ulcerative colitis

O presente trabalho objetivou, através de histoquímica com lectinas e análise digital de imagens, avaliar a expressão de carboidratos em amostras de colo normal e com colite ulcerativa. A partir de fragmentos de mucosa intestinal foram obtidos cortes histológicos (4mm) que foram incubados com lectinas (Con A, WGA, LTA e PNA), e os resultados das marcações foram avaliados através de microscopia óptica e sistema de análise de imagens. Os resultados obtidos revelaram uma intensa marcação para as células inflamatórias, principalmente neutrófilos infiltrados no tecido de reto e sigmóide, bem como células das glândulas intestinais. As lectinas WGA e LTA exibiram padrões distintos de marcação entre o epitélio normal e os casos de colite ulcerativa. As lectinas PNA e Con A falharam em reconhecer os carboidratos celulares nos casos estudados em ambos os grupos. Os resultados obtidos foram confirmados pela análise de imagem. As observações obtidas sugerem que as lectinas WGA e LTA são marcadores promissores para diferenciar o epitélio normal do padrão inflamatório da colite ulcerativa, indicando uma expressão distinta de N-acetilglicosamina e L-fucose nos respectivos casos estudados.