ABSTRACT
AIM: Aim of this study was to evaluate the effects of phytocomplexes of Uncaria, Shiitake and Ribes in terms of viability and inflammatory response on immune cell-derived cultures. METHODS: Standardized extracts of Uncaria, Shitake and Ribes and their commercial formulation were tested on cell lines PBMC, U937 and macrophage. The activity was evaluated in terms of cell viability (MTT test), variations of oxidative marker release (ROS and PGE2) and modulatory effects on immune response (gene expression of IL-6, IL-8 and TNFα, RT-PCR). RESULTS: Cell viability was not affected by extracts, except subtle variations observed only at higher doses (>250 µg/mL). The extract mixture was well tolerated, with no effects on cell viability up to doses of 500 µg/mL. Pre-treatment of macrophages with subtoxic doses of the extracts reduced the basal release of oxidative markers and enhanced the cell response to exogenous oxidant stimulation, as revealed by ROS and PGE2 release reduction. The same treatment on macrophage resulted in a selective modulation of the immune response, as shown by an increase of IL-6 mRNA and, partially, IL-8 mRNA, while a reduction was observed for TNFα mRNA. CONCLUSION: Data confirm that extracts and their formulations can act as regulator of the immune system with mechanisms involving the oxidative stress and the release of selected proinflammatory cytokines.
Subject(s)
Cytokines/metabolism , Immune System/drug effects , Phytotherapy/methods , Plant Preparations/pharmacology , Ribes , Shiitake Mushrooms , Uncaria , Cell Line , Cell Survival/drug effects , Cell Survival/immunology , Cytokines/genetics , Dinoprostone/metabolism , Drug Combinations , Gene Expression/drug effects , Gene Expression/immunology , Humans , Immune System/metabolism , Interleukin-6/genetics , Interleukin-6/metabolism , Interleukin-8/genetics , Interleukin-8/metabolism , Macrophages/drug effects , Macrophages/immunology , Oxidative Stress/immunology , Oxidative Stress/radiation effects , Plant Preparations/chemistry , Reactive Oxygen Species/metabolism , Ribes/chemistry , Shiitake Mushrooms/chemistry , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism , U937 Cells/drug effects , U937 Cells/immunology , Uncaria/chemistryABSTRACT
Plants of cranberry (Vaccinium macrocarpon) furnish edible fruits and derivates that have been used for the prevention and treatment of urinary tract infections. In the present work we compare two commercial extracts that contain proanthocyanins (PACs) at 4 percent and 20 percent for antimicrobial, antiproliferative, antiradical and protective properties against oxidative stress on cell lines. Both extracts showed antimicrobial activity (MIC values range 3-100 microg/ml). Extract at 20 percent PACs showed higher antiproliferative activity against HepG2 and MCF7 cells, but not against C2C12 cells. Both extracts showed a dose-dependent free-radical scavenging capacity, and a protective effect on the cell damage was also revealed by reduction of intracellular active oxygen species release. Cranberry extracts confirmed antioxidative properties and efficacy in reduction of cell viability that resulted stronger against tumor cells. The pretreatment with cranberry extracts, furthermore, reveal an increase of cell resistance against oxidative stress, suggesting a potential role as a dietary supplement in preventing free-radical damage. The proanthocyanidin content is critical to determine the extract efficacy. In cellular experiments the extracts resulted clearly differentiated in their activity, and the activity was strongly influenced by PACs content. Only in DPPH test the free radical scavenging activity seemed to be directly related to proanthocyanidins content.
