Natural whole grain components effectively control TNF alpha

Abstract

The immune system plays a key role in recognizing self and non-self compounds to keep our bodies healthy. This leads to a balancing act to provide sufficient immunological response to appropriate antigenic (foreign) agents, and not over-responding which creates detrimental effects on the host. Betaglucans from bacteria, fungi, and cereal grains are immune system stimulators that work through specific cell surface receptors to enhance the host response against antigenic organisms and tumors. One of the most significant signals the peripheral immune system utilizes to respond to an antigenic agent is the secretion of TNFα cytokine. This pleiotropic cytokine leads innate immune system defense, plays a key role in appetite, inflammation, and cancer, and regulates communication to other immune cells to respond in an organized configuration. First, this study demonstrated that beta-glucan from barley and oat as well as enzymatic treatment of beta-glucans from oats enhances immune stimulation through increased TNFα. I have shown through a model cell culture system (RAW 264.7 macrophages), a highly pure barley betaglucan (>91%; 10 μg/ml) and oat beta-glucan (>97%; 300 μg/ml) stimulate macrophages to produce 0.57 +/- 0.19 and 0.49 +/- 0.17 fg/cell TNFα, respectively quantified by ELISA). However, treatment of barley (10 μg/ml) and oat (300 μg/ml) beta-glucans with lichenase (10 u/μg; 1 hr, 40 C) significantly (p<0.05) increased TNFα production only in the oat beta-glucan (300 μg/ml) samples (1.48 +/- 0.55 fg/cell). Uncontrolled production of TNFα has been well documented in patients with chronic diseases such as CVD, obesity, and diabetes. Drugs that suppress TNFα production have relieved many deleterious symptoms and disease progression associated with these chronic diseases. Second, this study demonstrated that phenolic acids associated with cereal bran reduce TNFα production. Bran extracts from wheat and barley containing phenolic acids can almost completely diminish (~87%) the TNFα production from macrophages stimulated by cereal and bacterial beta-glucans. Purified commercially available cinnamic and protocatechuic acid significantly (p<0.05) reduce TNFα production from bacterial and cereal beta-glucan stimulated macrophages. The combined effects of caffeic and ferulic acid significantly reduced TNFα (59-88%) from cereal and bacterial beta-glucan stimulated macrophages. Through a model cell culture system, I demonstrated that beta-glucans, cereal bran extracts, and multiple phenolic acids from cereal bran have the potential to regulate an important cytokine of the immune system.