Joshua D. Lambert, Ph.D.

Research Interests:

The research focus of my laboratory is on the potential obesity and fatty liver disease preventive effects, as well as, the bioavailability and potential hepatotoxicity of dietary phytochemicals.  We have active research programs on polyphenols derived from tea, cocoa, mushrooms, and avocados.

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 (-)-epigallocatechin-3-gallate (EGCG), and other dietary polyphenols, as obesity preventive agents with the goal of understanding the underlying mechanisms of action and maximizing preventive activity using mouse models.

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.

My laboratory is also interested in the potential lung cancer preventive activities of dietary phytochemicals either as single agents or in combination with pharmaceutical compounds.  The focus is on establishing efficacy in cell culture and mouse models of lung cancer and studying the underlying mechanisms of action.

Selected Publications:

1. Gu Y, Hurst WJ, Stuart DA, Lambert JD  (2011)  Inhibition of Key Digestive Enzymes by Cocoa Extracts and Procyanidins.  J. Ag. Food Chem.  in press.
2. Grove KA, Sae-Tan S, Kennett MJ, Lambert JD (2011)  (-)-Epigallocatechin-3-gallate inhibits pancreatic lipase and reduces weight gain in high fat-fed obese mice.  Obesity.  in press.
3. Sae-Tan S, Grove KA, Kennett MJ, Lambert JD (2011)  (-)-Epigallocatechin-3-gallate Increases the Expression of Genes Related to Fat Oxidation in the Skeletal Muscle of High Fat-Fed Mice.  Food & Function.  2: 111 - 116.
4. Grove KA, Lambert JD.  (2010) Prevention of obesity by tea (Camellia sinensis), a critical review of the laboratory, epidemiological and human intervention studies.  J. Nutr.  140: 446 – 53.
5. Lambert JD, Kennett MJ, Sang S, Reuhl KR, Ju J, Yang CS.  (2010) Hepatotoxicity of High oral dose (-)-epigallocatechin-3-gallate in mice.  Food Chem. Toxicol.  48: 409 – 16.
6. Lambert JD, Elias RJ.  (2010) The antioxidant and pro-oxidant activities of green tea polyphenols: a role in cancer prevention.  Arch. Biochem. Biophys.  501: 65-72.
7. Lambert JD, Sang S, Hong J, Yang CS.  (2010)  Anticancer and anti-inflammatory effects of cysteine metabolites of the green tea polyphenol, (-)-epigallocatechin-3-gallate.  J. Ag. Food Chem.  58: 10016-9.
8. Lambert JD, Lu G, Lee MJ, Hu J, Ju J, Yang CS.  (2009)  Inhibition of lung cancer growth in mice by dietary mixed tocopherols.  Mol Nutr Food Res.  53: 1030 – 5.
9. Meyers RO, Lambert JD, Hajicek N, Pourpak A, Kalaitzis JN, Dorr RT.  (2009)  Synthesis, characterization and anti-melanoma activity of tetra-O-substituted analogs of nordihydroguaiaretic acid.  Bioorg. Med. Chem. Lett.  19: 4752 – 5.