ABSTRACT
During the screening of a variety of plant sources for their anti-obesity activity, it was found that a water-soluble extract, named PG105, prepared from stem parts of Cucurbita moschata, contains potent anti-obesity activities in a high fat diet-induced obesity mouse model. In this animal model, increases in body weight and fat storage were suppressed by 8-week oral administration of PG105 at 500 mg/kg, while the overall amount of food intake was not affected. Furthermore, PG105 protected the development of fatty liver and increased the hepatic beta-oxidation activity. Results from blood analysis showed that the levels of triglyceride and cholesterol were significantly lowered by PG105 administration, and also that the level of leptin was reduced, while that of adiponectin was increased. To understand the underlying mechanism at the molecular level, the effects of PG105 were examined on the expression of the genes involved in lipid metabolism by Northern blot analysis. In the liver of PG105-treated mice, the mRNA level of lipogenic genes such as SREBP-1c and SCD-1 was decreased, while that of lipolytic genes such as PPARalpha, ACO-1, CPT-1, and UCP-2 was modestly increased. Our data suggest that PG105 may have great potential as a novel anti-obesity agent in that both inhibition of lipid synthesis and acceleration of fatty acid breakdown are induced by this reagent.
Subject(s)
Anti-Obesity Agents/isolation & purification , Anti-Obesity Agents/therapeutic use , Cucurbita/chemistry , Fats/pharmacology , Lipid Metabolism/drug effects , Obesity/drug therapy , Obesity/metabolism , Adipocytes/cytology , Adipocytes/drug effects , Adipocytes/metabolism , Animal Feed , Animals , Body Weight/drug effects , Cell Differentiation/drug effects , Disease Models, Animal , Fatty Acids/metabolism , Liver/drug effects , Liver/metabolism , Male , Mice , Mice, Inbred C57BL , Obesity/pathology , Oxidation-Reduction , PPAR alpha/metabolism , Plant Extracts/chemistry , Plant Extracts/therapeutic use , WaterABSTRACT
Atopic dermatitis (AD) is a chronic inflammatory skin disease, which requires safe and effective pharmacological therapy. We previously found that two preparations from Actinidia arguta, PG102T, and PG102E, could modulate Th1/Th2 pathways and suppress IgE biosynthesis. This study was performed to assess the therapeutic effects of PG102T and PG102E on the development of dermatitis in NC/Nga mice, characterized by the spontaneous onset of AD along with an elevated level of IgE under conventional conditions. PG102T or PG102E administration significantly reduced dermatitis severity as well as scratching tendency in conventional mice. The suppression of dermatitis by PG102 was accompanied by a decrease in the plasma level of IgE, IgG1, and IL-4 and also by an increase in that of IgG2a and IL-12. The splenic level of IL-4, IL-5, and IL-10 was downregulated, whereas that of IFN-gamma and IL-12 was increased. The number of eosinophils and the expression of eotaxin and thymus and activation-regulated chemokine were decreased by PG102T or PG102E. Histological findings also indicated that the thickening of epidermis/dermis and the dermal infiltration of inflammatory cells including mast cells were greatly inhibited. These data suggest that PG102 may be effective therapeutic agents for the treatment of AD.
Subject(s)
Actinidia , Dermatitis, Atopic/drug therapy , Phytotherapy , Plant Extracts/therapeutic use , Plant Preparations/therapeutic use , Animals , Chemokine CCL11 , Chemokines, CC/metabolism , Cytokines/metabolism , Dermatitis, Atopic/metabolism , Dermatitis, Atopic/pathology , Disease Models, Animal , Female , Immunoglobulin E/metabolism , Immunoglobulin G/metabolism , Interleukin-10/metabolism , Interleukin-12/metabolism , Mast Cells/pathology , Mice , Mice, Inbred Strains , Spleen/metabolismABSTRACT
BACKGROUND: Various allergic responses are thought to result from the unbalanced development of T(H)1 and T(H)2 pathways and, subsequently, the overproduction of IgE. Therefore the modulation of T(H)1 and T(H)2 responses is a rational strategy for the treatment of allergic diseases. OBJECTIVE: The present study was performed to investigate the immune-modulating activities of PG102 preparations from Actinidia arguta in ovalbumin-sensitized murine models. METHODS: Two preparations from A arguta, PG102T and PG102E, were chosen for animal experimentation on the basis of their ability to regulate the production of IgE in U266B1 cells. The changes in splenic levels of cytokines and plasma levels of immunoglobulin isotypes were examined. The effects of PG102 on subcellular composition (CD4(+)IL-4(+) or CD19(+)IgE(+) cells), IgE production in B cells, and selective transcription factors were analyzed. RESULTS: Oral administration of PG102T and PG102E significantly decreased the level of selective T(H)2 cytokines, whereas it increased the level of T(H)1 cytokines. The differential effects of PG102T and PG102E on T(H)1 and T(H)2 cytokines were accompanied by a decrease in the plasma levels of IgE and IgG1 and by an increase in the plasma level of IgG2a. The percentages of both IL-4-producing T cells and IgE-producing B cells were decreased. The concentration of IgE produced within B cells also appeared to be reduced. Finally, PG102T and PG102E downregulated the level of GATA-binding protein 3, while inducing that of T-box transcription factor and nuclear factor of activated T cells c2. CONCLUSION: PG102T and PG102E have great potential as orally active immune modulators for the therapy of various allergic diseases.
