Nutrition Frontiers - Winter 2016

Date Posted: 

Wednesday, February 3, 2016

A newsletter from the Nutritional Science Research Group (NSRG), Division of Cancer Prevention, NCI

Volume 7, Issue 1

RESEARCH UPDATE: ON THE CLINICAL FRONT

DNA Methylation in CYP Genes May Predict Vitamin D Response

Image of an eldering woman wearing a hat and looking up toward the sun.

Cytochrome P450 (CYP) enzymes CYP2R1 and CYP27A1 are known key enzymes that play an important role in converting vitamin D from various sources into circulating 25(OH)D. In a study of 446 randomized white postmenopausal women receiving 1100 IU/day of vitamin D supplementation for at least 1-year, Zhou and colleagues looked at DNA methylation levels in the promoter region of CYP genes (CYP2R1, CYP24A1, CYP27A1, CYP27B1). Baseline DNA methylation levels of the CYPR21 and CYP24A1 genes differed significantly between the responders and the non-responders of vitamin D supplementation; non-responders had higher levels of DNA methylation levels in promoter region of CYPR21 and CYP24A1 and lower levels of serum 25 (OH)D. This inverse correlation, further verified in a validation study, suggests response to Vitamin D supplementation may differ depending on promoter methylation of the CYP genes. Further studies are needed to verify the potentiality of CYPR21 and CYP24A1 as biomarkers predicting vitamin D response.

Announcements

February 18-20, 2016
Multidisciplinary Head and Neck Cancer Symposium
Scottsdale, AZ

February 26-27, 2016
ASCO Quality Care Symposium
Phoenix, AZ

March 12-15, 2016
American Society of Preventive Oncology
Columbus, OH

March 12-13, 2016
Culinary Translation in Cancer Care
Washington, DC

March 14, 2016
IOM Workshop on Assessing Nutrition Care in Outpatient Oncology
Washington, DC

March 14-18, 2016
John Milner Nutrition and Cancer Prevention Research Practicum
Rockville, MD

March 15, 2016
Stars in Nutrition and Cancer
Bethesda, MD

April 02-06, 2016
Experimental Biology
San Diego

April 16-20, 2016
AACR Annual Meeting
New Orleans, LA

April 28-30, 2016
Oncology Nutrition DPG Symposium
Glendale, AZ

May 04-06, 2016
Accelerating Anticancer Agent Development and Validation Workshop
Bethesda, MD

May 16-18, 2016
National Nutrient Databank Conference
Alexandria, VA

May 17-20, 2016
Integrative Medicine and Health
Las Vegas, NV
 

RESEARCH UPDATE: WHAT'S NEW IN BASIC SCIENCE

Microbiota-Dependent Hepatic Lipogenesis Promotes Metabolic Syndrome

Diagram of internal organs with the liver highlighted.

Gut microbiota plays a key role in the host energy homeostasis and can be an environmental risk factor for metabolic diseases. Toll-like receptor 5 (TLR5) is required for gut microbiota homeostasis; TLR5-deficient (T5KO) mice develop an altered microbiota that promotes metabolic syndrome. Now Singh and colleagues show that short chain fatty acids (SCFAs) generated by gut bacterial fermentation of dietary fiber fuel lipogenesis in the liver, promoting insulin resistance and inflammation. When compared to wild-type littermates, T5KO mice generated more cecal SCFAs and increased liver de novo lipogenesis; dietary SCFAs aggravated metabolic syndrome in these mice. Hepatic stearoyl CoA desaturase-1 (SCD1) is a key regulatory enzyme in the homeostasis of saturated fatty acids and monounsaturated fatty acids (MUFA); deletion of SCD1 in T5KO mice attenuated hepatic oleate, a MUFA, enrichment and ameliorated metabolic syndrome. This study identifies a potential gut microbiota-liver axis underlying the development of metabolic syndrome in T5KO mice.

New Cannabinoid Receptor Associated with Obesity

Line drawings of human figures with various builds, from slender to obese.

The endocannabinoid system controls appetite, food intake and energy balance mainly through the CB1 receptor in white adipose tissue (WAT). The G protein-coupled receptor GPR55 is a novel cannabinoid receptor associated with obesity in humans. Lysophosphatidylinositol (LPI), the endogenous ligand of GPR55 is elevated in patients with obesity. Imbernon and colleagues found that the regulation of GPR55 in WAT and circulating LPI levels in rat are regulated by different physiological and pathophysiological settings involved in energy balance. The findings of this study revealed that GPR55 is regulated similarly to cannabinoid CB1 receptor in gonadal fat pad WAT, and both are influenced by nutritional status, gestation, postnatal development, sex steroids and pituitary factors. Further research is needed to determine if LPI/GPR55 could be potential targets for obesity treatment.

SPOTLIGHT: JAMES VERSALOVIC

Portrait of James Versalovic, MD, PhDJames Versalovic, MD, PhD serves as Pathologist-In-Chief, Head of the Department of Pathology, and as member of the Board of Directors at Texas Children's Hospital. He also serves as Vice Chair of Pathology and Immunology at Baylor College of Medicine, and Director of the Texas Children's Microbiome Center. Dr. Versalovic received his MD and PhD from Baylor College of Medicine. He seeks to understand the nature of the mammalian gut microbiome and how gut bacteria impact mucosal immunity and intestinal inflammation. Hi research explores microbiome replacement and manipulation of the intestinal microbiome. Dr. Versalovic was awarded a U01 for his project Gut L-Histidine Metabolism and Histamine Signaling in Colonic Neoplasia.

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Did You Know? Chia is a Rediscovered Powerhouse

Image of chia seeds.The tiny chia seed comes from the flowering Salvia hispanica plant, a member of the mint family. First recorded around 3500 B.C., the Aztecs and the Mayans believed it to offer supernatural powers. Unlike many ancient grains, which were lost to the modern world, chia's fame endured in Mexico, where the celebrated Tarahumara tribe credit their ability to run hundreds of miles to Iskiate - a drink mixture of chia seeds, lemon, and water.

A 2-tablespoon serving of black or white chia seeds provide 10 grams of fiber, loads of gluten-free plant proteins (5 grams), 180 mg of calcium, more than most dairy sources, and a whopping 4,900 mg of the healthy omega-3 fat, ALA! Unlike flaxseeds, which need to be grinded to release the health components of the seeds, chia seeds can be eaten whole or milled. Try dipping fruits into a bowl of chia seeds or toss the seeds in any salad for added crunch. In liquids, chia's soluble fiber swells into a gelatinous form, making it useful as an egg substitute or a soup thickener. The mighty chia can be added to anything you choose - from tabouleh, smoothies, dips, yogurts, oatmeal and the likes of pancake batter for added fluffiness.

References:

http://foodandnutrition.org/january-february-2014/chia-seeds-tiny-seeds-rich-history/
http://www.ancientgrains.com/chia-seed-history-and-origin/
https://www.foodmatters.com/article/14-proven-health-benefits-of-chia-seeds
http://www.whfoods.com/genpage.php?tname=foodspice&dbid=81