No abstract

The popularity and availability of herbal extracts has increased dramatically over the last decade, providing an inexpensive manner of self-medication. Although the efficacy of individual extracts is currently being intensively studied, research regarding complex mixtures is limited. Therefore, we evaluated the effects of three complex formulations including BRC-301, a polyherbal extract; BRC-304, a mixture of vitamins, minerals, antioxidant enzymes, botanical extracts and carotenoids; and BRC-306, a proprietary blend of Uncaria tomentosa (cat's claw) and Phytolens ® on murine dendritic cells (DCs). We hypothesized that these formulations would decrease the inflammatory responsiveness and innate function of DCs. To address this hypothesis, we evaluated the effects of BRC-301, 304, and 306 on DC2.4 cells and further assessed the effects of BRC-301 on bone marrow-derived DCs (bmDCs). LPS stimulation of DC2.4 cells and bmDCs induced production of NO, TNF-α, and IL-6, a response that was modulated by concomitant treatment with non-cytotoxic concentrations of BRC-301. In contrast, only the production of NO or IL-6 by LPS-activated DC2.4 cells was affected by BRC-304 or BRC-306, respectively. Flow cytometric evaluation following concurrent BRC-301 and LPS treatment revealed an increased relative expression of CD11c, CD86, and CD54 on bmDCs and an increased frequency of bmDCs expressing MHC II. Finally, BRC-301 enhanced the uptake of FITC-conjugated ovalbumin by bmDCs. Taken together, these results suggest that these commercially available formulations modulate the innate responsiveness of murine DCs and may enhance their ability to initiate T cellmediated immunity.

The popularity of herbal supplements, especially those with purported anti-inflammatory effects, has drastically increased in recent years as more people have turned to natural therapeutics. As the supplement industry is loosely regulated, the safety and efficacy of these products is poorly understood. In the present study, we examined the effects of natural product formulations prepared by the Biotics Research Corporation (BRC) on cyclooxygenase (COX) enzyme activity. We also evaluated the immune responsiveness of RAW264.7 macrophages, a key cell population involved in the inflammation, to those formulations. As a result, three supplements, BRC-301, BRC-304, and BRC-306, selectively inhibited COX-2, the inducible isoform involved in inflammation. Further evaluation of these three products indicated that BRC-304 and BRC-306 produced minimal effects on the production of inflammatory mediators by lipopolysaccharide (LPS)-stimulated macrophages. BRC-301 decreased the LPS-induced production of nitric oxide and IL-6, as well as CD40 expression. Collectively, these results suggest that the BRC-301 extract, comprising several polyphenolic natural products, may have a protective effect in chronic inflammatory disorders.