Green tea extract combined with exercise reduces fatty liver disease in mice
Although untested in human trials, results suggest a potential health strategy
February 14, 2020
Science Daily/Penn State
The combination of green tea extract and exercise reduced the severity of obesity-related fatty liver disease by 75% in mice fed a high-fat diet, according to researchers, whose recent study may point to a potential health strategy for people.
The outcome is important, explained Joshua Lambert, associate professor of food science, because nonalcoholic fatty liver disease is a significant global health problem that is expected to worsen. Because of the high prevalence of risk factors such as obesity and type 2 diabetes, fatty liver disease is forecast to afflict more than 100 million people by 2030. And there are currently no validated therapies for the disease.
In the study, mice fed a high-fat diet for 16 weeks that consumed green tea extract and exercised regularly by running on a wheel were found to have just a quarter of the lipid deposits in their livers compared to those seen in the livers of a control group of mice. Mice that were treated with green tea extract alone or exercise alone had roughly half as much fat in their livers as the control group.
In addition to analyzing the liver tissues of mice in the study, which was published recently in the Journal of Nutritional Biochemistry, researchers also measured the protein and fat content in their feces. They found that the mice that consumed green tea extract and exercised had higher fecal lipid and protein levels.
"By examining the livers of these mice after the study concluded and by screening their feces during the research, we saw that the mice that consumed green tea extract and exercised actually were processing nutrients differently -- their bodies were handling food differently," Lambert said.
"We think the polyphenols in green tea interact with digestive enzymes secreted in the small intestine and partially inhibit the breakdown of carbohydrates, fat and protein in food," he added. "So, if a mouse doesn't digest the fat in its diet, that fat and the calories associated with it pass through the mouse's digestive system, and a certain amount of it ends up coming out in its feces."
It may be significant, Lambert explained, that mice treated with both green tea extract and exercise had higher expression of genes related to the formation of new mitochondria. That gene expression is important, he said, because it provides markers that will help researchers understand the mechanism by which green tea polyphenols and exercise might work together to mitigate fatty liver deposits.
"We measured the expression of genes that we know are related to energy metabolism and play an important role in energy utilization," Lambert said. "In the mice that had the combination treatment, we saw an increase in the expression of genes that wasn't there before they consumed green tea extract and exercised."
More research is needed to see if there is a synergy created by green tea extract and exercise working together to reduce fat deposited in the liver, or if the effects are simply additive, Lambert pointed out. His research group in the College of Agricultural Sciences for 12 years has studied the health benefits of polyphenols -- often called antioxidants -- from green tea, cocoa, avocados and other sources.
In previous related research, Lambert and colleagues demonstrated that green tea extract and exercise together sharply reduced body mass and improved cardiovascular health of high-fat-fed mice. But because no human trials assessing the health benefits and risks of green tea combined with exercise have been conducted, he urges caution for people who decide to experiment with the health strategy on their own.
"I believe people should engage in more physical activity, and replacing high-calorie beverages with decaffeinated, diet green tea -- which has no calories -- is a smart move," he said. "Combining the two might have health benefits for people, but we don't have the clinical data yet."
https://www.sciencedaily.com/releases/2020/02/200214134655.htm
Can pomegranate juice protect the infant brain?
August 21, 2019
Science Daily/Brigham and Women's Hospital
In ongoing investigations, clinical researchers are exploring whether pomegranate juice intake during pregnancy can have a protective effect.
When it comes to protecting the newborn brain, taking steps to mitigate risk before birth may be critical. Some newborns, such as those with intrauterine growth restriction (IUGR), are at heightened risk. Being able to intervene before birth to aid in protecting the newborn brain may prevent the often-devastating effects of brain injury. In ongoing investigations, clinical researchers from Brigham and Women's Hospital are exploring whether pomegranate juice intake during pregnancy can have a protective effect. In a paper appearing in PLOS One, the team presents its preliminary findings from a clinical trial of expectant mothers whose babies were diagnosed with IUGR. The exploratory study, supported by National Institute of Health Grants, The Foundation for Barnes-Jewish Hospital and an unrestricted gift from POM Wonderful, shows promise, with evidence of better brain development and brain connectivity in infants born to mothers who consumed pomegranate juice daily. A second, larger clinical trial is currently underway at the Brigham to validate these findings.
"Our study provides preliminary evidence suggesting potential protective effects for newborns exposed to pomegranate juice while in utero," said senior author Terrie Inder, MBCHB, chair of the Department of Pediatric Newborn Medicine at the Brigham. "These findings warrant continued investigation into the potential neuroprotective effects of polyphenols in at-risk newborns, such as those with hypoxic-ischemic injury."
In cases of IUGR, a baby in the womb is measuring small for its gestational age, often because of issues with the placenta, which brings oxygen and nutrients to the growing fetus. One out of every 10 babies is considered to have IUGR. The process of birth itself can further decrease blood flow or oxygen to the baby, including to the baby's brain. If this is very severe, it can result in a condition known as hypoxic-ischemic injury, which contributes to almost one-quarter of newborn deaths worldwide.
Polyphenols, which include tannic acid and ellagitannins, are part of a class of antioxidants found in many foods and beverages, including nuts, berries, red wine and teas. Pomegranate juice is a particularly rich source of these molecules. Polyphenols are known to cross the blood-brain barrier, and studies in animal models have demonstrated protective effects against neurodegenerative diseases. To date, no clinical studies had evaluated the potential effects of giving pregnant women pomegranate juice to protect the brains of at-risk newborns.
The current randomized, controlled, double-blinded study enrolled 78 mothers from Barnes-Jewish Hospital obstetric clinic in St. Louis with IUGR diagnosed at 24-43 weeks' gestation. Women were randomized to receive 8 ounces of pomegranate juice daily or a taste/calorie matched placebo that was polyphenol free. Women drank the juice daily from enrollment until delivery. The team measured several aspects of brain development and injury, including infant brain macrostructure, microstructural organization and functional connectivity.
While the team did not observe differences in brain macrostructure, they did find regional differences in white matter microstructure and functional connectivity.
"These measures tell us about how the brain is developing functionally," said Inder. "We saw no difference in brain growth and baby growth, but we did see improvement in cabling network and brain development measured by synchronous blood flow and visual development of the brain."
The authors note that the findings warrant the need for a larger, rigorously designed clinical trial to allow continued investigation into the potential neuroprotective effects of polyphenols. Such a study is now underway at the Brigham.
"We plan to continue investigating these exciting findings," said Inder. "While the preliminary evidence shows promise, additional study and replication is needed."
https://www.sciencedaily.com/releases/2019/08/190821142719.htm
Coffee affects cannabis and steroid systems
March 15, 2018
Science Daily/Northwestern University
Coffee affects your metabolism in dozens of other ways besides waking you up, including your metabolism of neurotransmitters typically linked to cannabis, a study reports. The neurotransmitters related to the endocannabinoid system -- the same ones affected by cannabis -- decreased after drinking four to eight cups of coffee in a day. That's the opposite of what occurs after someone uses cannabis. The study also gives possible insight in the cause of munchies. Coffee may also increase the elimination of steroids.
It's well known that a morning cup of joe jolts you awake. But scientists have discovered coffee affects your metabolism in dozens of other ways, including your metabolism of steroids and the neurotransmitters typically linked to cannabis, reports a new study from Northwestern Medicine.
In a study of coffee consumption, Northwestern scientists were surprised to discover coffee changed many more metabolites in the blood than previously known. Metabolites are chemicals in the blood that change after we eat and drink or for a variety of other reasons.
The neurotransmitters related to the endocannabinoid system -- the same ones affected by cannabis -- decreased after drinking four to eight cups of coffee in a day. That's the opposite of what occurs after someone uses cannabis. Neurotransmitters are the chemicals that deliver messages between nerve cells.
Cannabinoids are the chemicals that give the cannabis plant its medical and recreational properties. The body also naturally produces endocannabinoids, which mimic cannabinoid activity.
In addition, certain metabolites related to the androsteroid system increased after drinking four to eight cups of coffee in a day, which suggests coffee might facilitate the excretion or elimination of steroids. Because the steroid pathway is a focus for certain diseases including cancers, coffee may have an effect on these diseases as well.
"These are entirely new pathways by which coffee might affect health," said lead author Marilyn Cornelis, assistant professor of preventive medicine at Northwestern University Feinberg School of Medicine. "Now we want to delve deeper and study how these changes affect the body."
Little is known about how coffee directly impacts health. In the new study, Northwestern scientists applied advanced technology that enabled them to measure hundreds of metabolites in human blood samples from a coffee trial for the first time. The study generates new hypotheses about coffee's link to health and new directions for coffee research.
The paper will be published March 15 in the Journal of Internal Medicine.
Drinking lots of coffee for science
In the three-month trial based in Finland, 47 people abstained from coffee for one month, consumed four cups a day for the second month and eight cups a day for the third month. Cornelis and colleagues used advanced profiling techniques to examine more than 800 metabolites in the blood collected after each stage of the study.
Blood metabolites of the endocannabinoid system decreased with coffee consumption, particularly with eight cups per day, the study found.
The endocannabinoid metabolic pathway is an important regulator of our stress response, Cornelis said, and some endocannabinoids decrease in the presence of chronic stress.
"The increased coffee consumption over the two-month span of the trial may have created enough stress to trigger a decrease in metabolites in this system," she said. "It could be our bodies' adaptation to try to get stress levels back to equilibrium."
The endocannabinoid system also regulates a wide range of functions: cognition, blood pressure, immunity, addiction, sleep, appetite, energy and glucose metabolism.
"The endocannabinoid pathways might impact eating behaviors," suggested Cornelis, "the classic case being the link between cannabis use and the munchies."
Coffee also has been linked to aiding weight management and reducing risk of type 2 diabetes.
"This is often thought to be due to caffeine's ability to boost fat metabolism or the glucose-regulating effects of polyphenols (plant-derived chemicals)," Cornelis said. "Our new findings linking coffee to endocannabinoids offer alternative explanations worthy of further study."
It's not known if caffeine or other substances in coffee trigger the change in metabolites.
https://www.sciencedaily.com/releases/2018/03/180315091253.htm