Volume 10, Issue 4
Dear Nutrition Enthusiast,
RESEARCH UPDATE: ON THE CLINICAL FRONT
Selectively Inhibitory Effects of Green Tea Polyphenols on Microbial Metabolism
The bioavailability of green tea polyphenols (GTP) is limited and unabsorbed GTP can have bi-directional metabolic interactions with gut microbes after reaching the large intestine. In this study, Zhou and colleagues conducted metabolomic analysis on the samples from healthy postmenopausal women who consumed GTP extract daily for 12 months (The Minnesota green tea trial) to determine the influences of GTP on fecal and urinary metabolomes. Major GTP and their direct sulfate and glucuronide metabolites were largely absent in feces and urine, whereas the GTP microbial metabolites phenyl-ɣ-valerolactones and phenylvaleric acids were abundant, suggesting extensive microbial biotransformation of GTP and bioavailability of these microbial metabolites. Chronic consumption of GTP did not significantly affect fecal microbiome and major microbial metabolites, including secondary bile acids and short-chain fatty acids. However, GTP selectively decreased the levels of microbial metabolites of aromatic amino acids (AAA), potentially through competitive inhibition. This study revealed extensive contributions of microbial metabolism to the formation of GTP metabolites and the influences of GTP on microbial production of AAA metabolites.
The National Cancer Institute and National Institutes of Health’s John Milner Nutrition and Cancer Prevention Research Practicum will take place March 16-20, 2020, and is now accepting applications –deadline is November 29, 2019. For details about the practicum, eligibility and details for applying to the practicum, go to: John Milner Nutrition and Cancer Prevention Research Practicum.
Stars in Nutrition and Cancer lecture Lifestyle and Breast Cancer: Addition by Subtraction and the Value of Randomized Clinical Trials by Dr. Rowan Chlebowski available for viewing. All past lectures have been approved by the CDR for CPE credit for RDNs.
Body Composition and Cancer Webinar Series is a monthly webinar series which received support from the NCI. Webinars take place on the third Thursday of the month from 12-1 PST (3-4 EST) through June 2020. If you interested in receiving announcements or call-in information for the webinar series, please email Adam Boroian at adam.boroian
@kp.org, and you will be added to the mailing list.
October 26-29, 2019
Food & Nutrition Conference & Expo
Academy of Nutrition and Dietetics
November 6-8, 2019
Las Vegas, NV
November 12-13, 2019
NIH Sensory Nutrition and Disease Workshop
National Institute of Diabetes and Digestive and Kidney Diseases
Personalized Nutrition 2019
American College of Nutrition
San Diego, CA
RESEARCH UPDATE: WHAT’S NEW IN BASIC SCIENCE
Role of Host GPR120 and Omega-3’s in Inhibition of Prostate Cancer
GPR120, a G-protein coupled receptor is involved in modulation of metabolism, endocrine and immune function and has an anti-inflammatory effect when activated by omega-3 fatty acids (ω-3 FAs). Liang and colleagues evaluated ω-3 FAs anticancer effects through GPR120 on host M2-like tumor-associated macrophages (M2-TAMs). Immunocompetent wild-type (WT) and GPR120-knockout (GPR120KO) mice received 30% of energy from dietary fish oil (ω-3) or corn oil (ω-6). Compared to an ω-6 diet, the ω-3 diet decreased MycCap allograft prostate tumor growth, numbers of M2-TAMs in tumor tissue, and gene expression of M2-TAM markers in WT mice. However, ω-3 FAs had no anticancer effects on GPR120KO mice. A correlation between GPR120 and cell cycle progression genes and lower proliferation (Ki-67 index) in archived human stromal tissue indicated individuals with a higher GPR120 expression may be better responders to ω-3 fish oil interventions. These findings suggest host GPR120 may play a role in the anticancer effects of dietary ω-3 FAs. Clinical studies are warranted to evaluate if host GPR120 expression predicts efficacy of dietary ω-3 FAs and a possible precision approach to fish oil therapy in prostate cancer.
CCAR2, An Early Target for Acetylation in Colon Cancer Cells Treated with Sulforaphane
Cell cycle and apoptosis regulator 2 (CCAR2) has gained attention as a master regulator of metabolism, aging, and cancer. CCAR2 is thought to function in the regulation of Wnt/β-catenin signaling for promotion of colorectal cancer, and over-expression of CCAR2 in colon tumors is associated with reduced patient survival. Rajendran and colleagues identified CCAR2 as an early target for acetylation in colon cancer cells treated with the broccoli compound sulforaphane. They found that sulforaphane-induced acetylation sites on CCAR2 interfered with Wnt coactivator functions and influenced CCAR2 acetyl reader interactions, including those of bromodomain and extraterminal domain (BET) family members and BRD9. Treatment with the BET inhibitor JQ1 synergized with sulforaphane in colon cancer cells, and suppressed tumor development effectively in a preclinical model of colorectal cancer. Hear the authors explain the results, which highlight the competition that exists among the readers of acetylated histone and non-histone proteins, and provide a mechanistic basis for potential new therapeutic avenues involving epigenetic combination treatments.
SPOTLIGHT INVESTIGATOR: KATHLEEN ARCARO
Kathleen Arcaro, PhD, is a Professor of Environmental Toxicology in the Department of Veterinary and Animal Sciences at the University of Massachusetts Amherst. For the past 15 years, Dr. Arcaro’s research has focused on using breast milk to study modifiable biomarkers of breast cancer risk. She has shown that DNA methylation profiles of sloughed epithelial cells naturally present in milk provide information about individual risk, and that inflammatory profiles detected in milk are associated with breast cancer risk factors. After demonstrating the feasibility of increasing fruit and vegetable consumption among breastfeeding women to 8 to 10 daily servings, Dr. Arcaro and her colleagues received an R01, Fruit and Vegetable Intervention in Lactating Women to Reduce Breast Cancer Risk: Effects on Breast Cell DNA Methylation, Breast Inflammation, and Weight.
Did you know? The Famed Figs – A Thing Before Refined Sugar
Figs (ficus carica), a native to the Middle East and Mediterranean, date back to the Bible. Figs blossom on one of the world’s oldest trees, the Ficus tree. This succulent natural sweetener has long been appreciated by many – from the Greeks, whose laws prohibited the export of this delicate fruit to Thomas Jefferson, who fell in love with the greenish-white French Marseilles fig variety and planted them in Virginia. Although considered a fruit, figs are actually a flower inverted into themselves. The fleshy skin and seeds of fresh figs are a rich source of folate, potassium, calcium, magnesium, iron, copper, and vitamins A and K, along with fiber and prebiotics. This Fall, consider adding freshly sliced or roasted figs to spinach, kale, fennel and arugula salads, or try something warm such as fig-braised chicken with spiced walnuts. Be mindful to eat the dried variety in moderation because they are high in natural sugars and contain 95 grams carbohydrates per cup, and all figs can exert a laxative effect!