Immunosuppressive and hepatoprotective potential of Sarcococca saligna and its biomarker components.

Sarcococca saligna methanolic extract, fractions and isolated pure compounds saracocine (1), saracodine (2), pachyximine-A (3) and terminaline (4) were found to possess potent immunosuppressive activities. The fractions and compounds were tested in-vitro for their effects on human T-cell proliferation, and cytokine (IL-2) production. All the fractions, sub-fractions and purified compounds showed significant suppressive effect on IL-2 production in a dose-dependent manner. They also exhibited a suppressive effect on the phytohemagglutinin-stimulated T-cell proliferation. None of the extracts and purified compounds showed any cytotoxicity effects on the 3T3 mice fibroblast cell line. The crude extract, DCM fraction (pH9), DCM fractions (pH7) and one of the steroidal alkaloids (terminaline) were checked in-vivo for their hepato-protective potential against CCl4-induced liver injury. In in-vivo experiments, the basic and neutral DCM fractions and terminaline (4) significantly reduced inflammation in the liver. DCM fraction (pH9), DCM fractions (pH7) and compound 4 reduced the serum enzyme levels (ALT, AST, and ALP) down to control levels despite CCl4 treatment. They also reduced the CCl4-induced damaged area to almost zero as assessed by histopathology. The pale necrotic areas and mixed inflammatory infiltrate which are seen after CCl4 treatment were absent in the cases of basic, neutral fractions and terminaline treatment. These hepato-protective effects were better than the positive control silymarin. Our results suggest the therapeutic effect of S. saligna extract, fractions and bioactive steroidal alkaloids against CCl4-induced liver injury in vivo and their immunosuppressive function in vitro.

Identification of novel Interleukin-2 inhibitors through computational approaches.

Interleukin-2 (IL-2), is a 15.5-kDa cytokine that is now emerging as a target in drug discovery for novel therapeutic approaches in several autoimmune disorders. In an attempt to identify new inhibitors for the IL-2/IL-2R interaction, virtual screening (VS) was performed. Four different docking programs (GOLD, FlexX, Glide, and LigandFit) in combination with several scoring functions were used to identify novel IL-2/IL-2R interaction inhibitors.VSof a database of 6,000compounds resulted in the identification of three novel and moderately active hits with IC50 values ranging from 6.6 to 44.3 µM. Furthermore, the effect of these three compounds on the expression of IL-2Rα was assessed. The three active hits showed dose-dependent inhibitory effects on the expression of IL-2Rα with an IC50 range of 5.8 to 140µM. The cytotoxicity of these active hits was assessed using three normal cell-lines: bovine kidney cell-line (MDBK), mouse fibroblast cell-line (3T3), and rat hepatocytes cell-line (CC-1).Thecompoundswere found to have negligible cytotoxicity compared to their IC50 as IL-2/IL-2R interaction inhibitors. These results demonstrate that our VS protocol can identify novel inhibitors for IL-2/IL-2R interaction that effectively suppress IL-2 production, as well as the expression of IL-2Rα. Optimization of these molecules could lead to improved and effective anti-inflammatory therapeutics.

New cyclomyrsinol diterpenes from Euphorbia aellenii with their immunomodulatory effects.

Chloroform-acetone extract of the aerial parts of Euphorbia aellenii Rech. f. (Euphorbiaceae) was investigated for its diterpenoidal constituents. This led to the isolation of two new and one known cyclomyrsinol-type diterpenes 1-3. The structures were elucidated on the basis of 1D and 2D (1)H and (13)C NMR techniques, and in vitro immunomodulatory activity was evaluated by standard proliferation of human peripheral blood lymphocytes. Results showed that all the three compounds were found to inhibit lymphocyte proliferation significantly (p < 0.05) at 50 µg/ml concentration. Among them, compound 2 showed more activity against phytohemagglutinin-activated T-cell proliferation with an IC(50) of 40.4 ± 9.35 µg/ml.

New immunosuppressive cyclomyrsinol diterpenes from Euphorbia kopetdaghi Prokh.

Aceton: chloroform (1:2) extracts of the aerial parts of Euphorbia kopetdaghi Prokh. (Euphorbiaceae) were investigated for its diterpenoids and afforded three new five-membered ring, pentacyclic myrisinane polyester comprised of 3,5,10-O-triacetyl-8-O-isobutanoyl-14-O-benzoylcyclomyrsinol (1), 3,5,10,14-O-tetraacetyl-8-O-(2'-methyl butanoyl)-cyclomyrsinol (2) and 3,5,10,14-O-tetracetyl-8-O-isobutanoylcyclomyrsinol (3). The structures were elucidated based on (13)C- and (1)H-NMR as well as 2D-NMR, IR and different MS spectra and the immunomodulation activity for compound 1 was evaluated through lymphocyte proliferation assay, IL-2 assay, oxidative burst of phagocytic leukocytes and through their cytotoxicity on two cell lines. Compound 1 showed significant suppressive activity against phytohemagglutinin-activated T-cell proliferation with an IC(50) of 1.83 µg mL(-1), IL-2 suppressive activity with an IC(50) of 19.0 µg mL(-1) and oxidative burst suppressive activity with an IC(50) of 1.6 µg mL(-1) and ignorable cytotoxic effect on the CC-1 rat hepatocyte and 3T3-L1 mouse fibroblast cell-lines.

Flavonol Glycosides from Euphorbia microsciadia Bioss. with their Immunomodulatory Activities.

FOUR KNOWN FLAVONOIDS: quercetin 3-O-ß-D-rutinoside (Q3Rut), myricetin 3-O-ß-D-galactopyranoside (M3Gal), quercetin 3-O-ß-D-galactopyranoside (Q3Gal) and quercetin 3-O-ß-D-glucopyranoside (Q3Glc), for the first time were isolated from aerial parts of Euphorbia microsciadia. The chemical structure of them was elucidated on the basis of 1 and 2 D-NMR spectra and different spectroscopic techniques. The immunomodulatory activities of isolated compounds were compared using standard T-cell proliferation assay. These data showed that lymphocyte suppression activity of flavonoids (1-4) were comparatively lower than prednisolon as a standard drug. Immunosuppressive activity of flavonoids with hydroxyl groups at both 3'-and 4'-positions in their B-ring (Q3Gal) were more than those with 3'-,4'-and 5'-hydroxyl substitution (M3Gal). In these compounds, Q3Gal showed the most inhibitory activity, whereas M3Gal showed the least lymphocyte antiprolifeartive activity.

Cycloartanes from Euphorbia aellenii Rech. f. and their Antiproliferative Activity.

The cytotoxic chloroform fraction of Euphorbia aellenii afforded two cycloartane type triterpenes-cycloart-25-en-3ß,24-diol (1) and 24-methylene-cycloartan-3ß-ol (2)-for the first time from this plant. Preparation of cycloartane derivatives, 3ß, 24-O-diacetyl-cycloart-25-en as compound 3 and 3ß-O-acetyl-24-methylene-cycloartan (4) were conducted by acetylating of 1 and 2, respectively. The structures of the isolated compounds were elucidated by spectroscopic methods and their activities evaluated by proliferation assay on human peripheral blood lymphocytes (PBLs). Comparing the results suggested that anti-proliferation effect of these compounds on PBLs might be due to the presence of free 3-OH group while masking the free OH groups by acetylation, could induce proliferation activity.