Highlight
Understanding metallic flavor perception to improve cancer therapy
Figure 1. Metallic flavor intensity increases with oxidation expressed as malondialdehyde (MDA – lipid oxidation biomarker)
Achievement/Results
NSF-funded researchers, Dr. Susan Duncan (Food Science and Technology), Dr. Andrea Dietrich (Civil and Environmental Engineering), and Dr. YongWoo Lee (Biomedical sciences and Pathobiology) from Virginia Tech in collaboration with Dr. Gleen Lesser (Hematology and Oncology) at Wake Forest are investigating the mechanisms of taste and odor abnormalities in cancer patients. MILES associate Pinar Omur-Ozbek (a recent graduate, December 2008) under the guidance of Dr. Dietrich investigated the mechanisms of metallic taste flavor perception and strategies to ameliorate its occurrence. They found lipid oxidation in the mouth is associated with metallic flavor/taste perception. Metal ions interact with taste buds and participate in chemical reactions resulting in odorous compounds being formed. Metallic flavor is a problem for tap water consumers due to corrosion of iron and copper metals in the pipes, and it is also a problem for cancer patients receiving therapies such as chemotherapy and radiotherapy.
Cancer patients are sensitive to bitter and metallic flavors from foods such as meat, coffee, and tea. Occurrence of metallic flavor in cancer patients can result in lower quality of life and compromised nutrition status if they reduce food and beverage consumption. These researchers have studied metallic flavor in humans. These studies involve fundamental chemistry to investigate the reactions of iron and copper metal ions with oral tissues. Metal ions react with phospholipids, fatty acids, and proteins in the mouth tissues and saliva to produce odorous aldehydes and ketones, products of lipid oxidation which contribute to metallic flavor/taste.
The collaboration between researchers at Virginia Tech and Wake Forest will help provide researchers and physicians a better understanding of the causes of taste and odor perceptions in cancer patients with the aim to develop treatments for such patients to improve their quality of life and nutrition status. Approximately 75% of cancer patients receiving chemotherapy report altered taste/flavor perceptions with metallic taste being a major concern. This altered taste perception results in decreased food consumption, anxiety, and malnutrition in severe cases which may impact the chance of survival of such patients. In addition, Dr. Duncan and Dr. Dietrich are expanding their research efforts to evaluate lactoferrin (a milk protein) as a natural occurring glycoprotein in milk which as metal chelating properties. This property makes lactoferrin effective in reducing metal-induced oxidation and a valuable bioactive molecule. The researchers hope that a lactoferrin-based therapy may improve the quality of life and indirectly improve the nutritional status of cancer patients.
Address Goals
Discovery: Foster research that will advance the frontiers of knowledge, emphasizing areas of greatest opportunity and potential benefit and establishing the Nation as a global leader in fundamental transformational science and engineering. The goal of these multidisciplinary across university research is to understand the mechanisms of metallic flavor/taste development in cancer patients. Poor quality water is of concern for tap drinking water consumers; however, cancer patients experience a set of side effects after cancer therapies. Understanding the mechanisms of metallic taste can help cancer patients who are hopeful for a better life after facing cancer itself.
Learning: Cultivate a world-class, broadly inclusive science and engineering workforce and expand the scientific literacy of all citizens. Metallic taste perception affects the recovery and quality of life of cancer patients. Of greater concern is the potential effects it may have on the nutrition status of these patients which can lead to morbidities. These researchers hope to provide the basic knowledge on metallic taste formation and investigate solutions to prevent it. This will provide oncologists with alternative therapies for their patients aside from the current chemotherapy and radiotherapy practices.
