Joshua D. Lambert, Ph.D.

Research Interests

Prevention of Obesity and Fatty Liver Disease by Dietary Polyphenols  The emerging epidemic of obesity, and related complications including fatty liver disease, makes the development of preventive strategies a key public health concern.  My laboratory is currently studying the effectiveness of polyphenols from green tea (Camellia sinensis) and cocoa (Theobroma cacao) in preventing obesity and non-alcoholic fatty liver disease with the goal of understanding the underlying mechanisms of action.

Mitigation of Gastrointestinal Inflammation and Cancer by Dietary Phytochemicals  Chronic inflammation plays an important role in the pathology of inflammatory bowel disease (IBD) and the development of gastrointestinal cancers.  My laboratory is currently studying the anti-inflammatory and cancer inhibitory activities of polyphenols from cocoa, tea, and other food sources, as well as protein and fiber from soy in cell-line and animal models of gastrointestinal inflammation, and oral and colon cancers.  Our goal is to demonstrate potential anti-inflammatory and cancer inhibitory efficacy, identify putative underlying mechanism of action, and characterize the key phytochemicals responsible for the activity.  

Bioavailability and Potential Toxicity of Dietary Phytochemicals  Although dietary phytochemicals, including EGCG, have a long history of safe use as part of the diet, there is emerging evidence that high doses of some of these compounds, given in concentrated dose forms (capsules, tablets, etc.) may cause liver toxicity in humans.  Research in my laboratory is focused on understanding the dose-response relationships and mechanisms of action underlying these potential toxicities in mice.   We are studying the role of biotransformation and bioavailability in determining toxic potential of important dietary phytochemicals, and assessing the potential for phytochemical-drug interactions that could lead to adverse effects.

Characterization of Factors that Impact the Chemistry and Bioactivity of Food and Medicinal Plants  Varying plant genetics, environmental conditions, production, and post-harvest processing factors may impact plant chemistry. This variability complicates the relationship between plant consumption and human health, and may confound attempts to study the putative health beneficial effects of food and medicinal plants in humans.  My research group has on-going collaborative studies to (1) examine the effect of post-harvest processing on the chemistry and anti-inflammatory effects of cocoa; (2) characterize variability in the chemistry and anticancer/anti-inflammatory effects of cloves (Syzygium aromaticum); and (3) quantify the effects of genetic, environmental, and production factors on the chemistry of goldenseal (Hydrastis canadensis).  Our goal is to help better define the factors that influence the relationship between food/medicinal plants and human health.  

Funding

Our research is or has been funded by:

• USDA National Institute of Food and Agriculture
• The National Center for Complementary and Alternative Medicine
• The National Cancer Institute
• The American Institute for Cancer Research
• Tobacco Centers of Regulatory Science (P50), US National Institutes of Health (NIH) and US Food and Drug Administration (FDA)
• The Pennsylvania Soybean Board
• The Cherry Marketing Institute
• The California Table Grape Commission

Graduate Program Affiliation

I am a member of the graduate faculty in the following programs:

• Food Science
• Molecular, Cellular, and Integrative Biosciences
• Integrated and Biomedical Physiology

Selected Publications (from more than 100)

1. Ureña J, Ebersol L, Silakov A, Elias RJ, Lambert JD (2020) Impact of atomizer age and flavor on in vitro toxicity of aerosols from a third-generation electronic cigarette against human oral cells.  Chem Res Toxicol. 33: 2527 – 37.   
2. Wang L, Tao L, Hao L, Stanley TH, Huang K-H, Lambert JD, Kris-Etherton PM (2020) A moderate-fat diet with one avocado per day increases plasma antioxidants and decreases the oxidation of small, dense LDL in adults with overweight and obesity: a randomized controlled trial. J Nutr. 150: 276 – 84. 
3. Khoo WY, Chrisfield BJ, Sae-tan S, Lambert JD (2020) Mitigation of non-alcoholic fatty liver disease in high fat-fed mice by the combination of decaffeinated green tea extract and voluntary exercise.  J Nutr Biochem. 76:108262.
4. Cirillo S, Ureña J, Lambert JD, Vivarelli F, Canistro D, Paolini M, Cardenia V, Rodriguez-Estrada, Ritchie JP, Elias RJ (2019) Impact of heating coil resistance on the production of reactive carbonyls, reactive oxygen species and induction of cytotoxicity in human lung cancer cells in vitro. Regul Toxicol Pharmacol. 109:104500. 
5. Lambert JD, VanDusen SR, Cockroft JE, Smith E, Greenwood DC, Cade JE (2019) Bitter taste sensitivity, food intake, and risk of malignant cancer in the UK Women's Cohort Study.  Eur J Nutr. 58: 2111 – 21. 
6. Hatzakis E, Mazzola E, Shegog RM, Ziegler GR, Lambert JD (2019) Perseorangin: a natural pigment from Avocado (Persea americana) seed. Food Chem. 293: 15 – 22. 
7. Dabas D, Elias RJ, Ziegler GR, Lambert JD (2019) In vitro antioxidant and cancer inhibitory activity of a colored avocado seed extract.  Int J Food Sci. 2019: 6509421. 
8. Racine KC, Lee AH, Wiersema BD, Huang H, Lambert JD, Stewart AC, Neilson AP (2019) Development and characterization of a pilot-scale model cocoa fermentation system suitable for studying the impact of fermentation on phenolic compounds and quality of cocoa.  Foods. 8: 102. 
9. Dabas D, Ziegler GR, Lambert JD (2019) Anti-inflammatory properties of a colored avocado seed extract.  Adv Food Technol Nutr Sci. 5: 8 – 12. 

Teaching Responsibilities

• FDSC 406, Physiology of Nutrition
• FDSC 407, Food Toxins
• FDSC 501, Research Methods