Gut bacteria from wild mice boost health in lab mice

Laboratory mice that are given the gut bacteria of wild mice can survive a deadly flu virus infection and fight colorectal cancer dramatically better than laboratory mice with their own gut bacteria; researchers report (October 19, 2017) in the journal Cell.

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The immunological benefits from the wild mice’s gut bacteria may, in part, explain a persistent problem in disease research: Why disease experiments in lab mice, such as vaccine studies, turn out very differently in humans or other animals. “We think that by restoring the natural ‘microbial identity’ of laboratory mice, we will improve the modeling of complex diseases of free-living mammals, which includes humans and their diseases,” said Barbara Rehermann, M.D., senior author of the paper. Rehermann is chief of the Immunology Section, Liver Diseases Branch, of the NIH’s National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). “By being so different, natural microbiota will help us to discover protective mechanisms that are relevant in the natural world and absent in the laboratory,” said Stephan Rosshart, M.D., first author of the paper and NIDDK postdoctoral fellow.

Mammals, humans included, depend on their microbiota, the collection of microorganisms they host in and on their bodies. Evolution shapes each animal’s microbiota, favoring populations of organisms that help the animal survive their environment and diseases they encounter. However, laboratory mice are not random house mice plucked from a field or basement. Laboratory mice are carefully bred, fed, and raised in tightly controlled conditions so that each mouse has predictable traits and genetics. This is an excellent advantage in basic biology research, but creating that predictability means that a controlled environment, and not the survival pressures of the outside world, shaped the microbiotas of laboratory mice.

“We hypothesized that this might explain why laboratory mice, while paramount for understanding basic biological phenomena are limited in their predictive utility for modeling complex diseases of humans and other free-living mammals,” said Rosshart. Therefore, the researchers tried to give laboratory mice back what they have lost: A naturally co-evolved wild mouse gut microbiota. The researchers trapped more than 800 wild mice from eight locations across Maryland and the District of Columbia to find healthy, suitable candidates for a gut microbiota donation. They then tested and compared the gut microbiomes (collective genomes of the gut microbiota) of the wild mice (Mus musculus domesticus) and a standard strain of laboratory mice, called C57BL/6, from multiple sources. The researchers confirmed that C57BL/6 mice had distinct gut microbiomes from wild mice.

Researchers then introduced (engrafted) the microbiota of wild mice to pregnant, germ-free C57BL/6 mice. Germ-free mice are raised in a sterile environment and don’t have microbiomes of their own. For a control group comparison, the researchers also engrafted microbiota from regular C57BL/6 mice into a separate group of pregnant, germ-free mice. Four generations later, the mice still carried either the wild microbiomes or the control laboratory microbiomes passed down from their foremothers.

When exposed to a high dose of influenza virus, 92 percent of the laboratory mice with wild microbiomes survived, whereas only 17 percent of laboratory mice and mice in the control group survived. In other experiments, the laboratory mice with wild microbiomes had better outcomes in the face of induced colorectal tumors, whereas the other mice had a higher number of tumors and more severe disease. The beneficial effects of the wild microbiota were associated with reduced inflammation in both models.

The researchers note that more work and evaluation is needed for definitive results, and they hope to improve and expand upon the method of using natural microbiomes in laboratory mice. “We are planning to create a complete microbiological fingerprint of natural microbiota and its potential trans-kingdom interaction by describing all components of the microbiome — for example, viruses and fungi — in parallel and at various body sites,” Rehermann said.

So, it’s ok not to be a germaphobe and let the little critters run free, every now and then!

Adapted from: Rosshart et al. Wild Mouse Gut Microbiota Promotes Host Fitness and Improves Disease ResistanceCell, 2017 DOI: 10.1016/j.cell.2017.09.016

Nutrition Nugget

Use A Vegetable Substitute! Love spaghetti? Try spaghetti squash. Sure it’s not pasta but just try it, you may like it! Love mashed potatoes? Try mashed cauliflower (OMG it’s heavenly! You will never go back to potatoes). Mix in some Greek yogurt to give it a thick, creamy texture like regular mashed potatoes. While vegetables most likely won’t be the carbs you know and love, they’re a good way to make your favorite meals healthier!

Inspirational Nugget

Even when things seem hopeless, life has a way of defying the odds, overcoming the obstacles and coming back strong. So never give up, regardless of how hopeless things may seem. There is ALWAYS a way.



GM soybean oil causes less obesity and insulin resistance but is harmful to liver function

Mouse study compares Plenish to conventional soybean, coconut, and olive oils. 


Researchers at the University of California, Riverside have tested a genetically-modified (GM) soybean oil used in restaurants and found that while it induces less obesity and insulin resistance than conventional soybean oil, its effects on diabetes and fatty liver are similar to those of conventional soybean oil. Soybean oil is the major vegetable cooking oil used in the United States, and its popularity is on the increase worldwide. Rich in unsaturated fats, especially linoleic acid, soybean oil induces obesity, diabetes, insulin resistance, and fatty liver in mice. UC Riverside researchers tested Plenish®, a genetically-modified (GM) soybean oil released by DuPont in 2014. Plenish is engineered to have low linoleic acid, resulting in an oil similar in composition to olive oil, the basis of the Mediterranean diet and considered to be healthful.

The study, published (October, 2017) in Nature Scientific Reports, is the first to compare the long-term metabolic effects of conventional soybean oil to those of Plenish. The study also compares both conventional soybean oil and Plenish to coconut oil, which is rich in saturated fatty acids and causes the least amount of weight gain among all the high-fat diets tested. “We found all three oils raised the cholesterol levels in the liver and blood, dispelling the popular myth that soybean oil reduces cholesterol levels,” said Frances Sladek, a professor of cell biology, who led the research project. Next, the researchers compared Plenish to olive oil. Both oils have high oleic acid, a fatty acid believed to reduce blood pressure and help with weight loss.

“In our mouse experiments, olive oil produced essentially identical effects as Plenish; more obesity than coconut oil, although less than conventional soybean oil, and very fatty livers, which was surprising as olive oil is typically considered to be the healthiest of all the vegetable oils,” said Poonamjot Deol, an assistant project scientist working in Sladek’s lab and the co-first author of the research paper. “Plenish, which has a fatty acid composition similar to olive oil, induced hepatomegaly, or enlarged livers, and liver dysfunction, just like olive oil.” Sladek explained that some of the negative metabolic effects of animal fat that researchers often see in rodents could actually be due to high levels of linoleic acid, given that most U.S. farm animals are fed soybean meal. “This could be why our experiments are showing that a high-fat diet enriched in conventional soybean oil has nearly identical effects to a diet based on lard,” she said.

The researchers further speculate that the increased consumption of soybean oil in the U.S. since the 1970’s could be a contributing factor to the obesity epidemic. According to the Centers for Disease Control and Prevention, 35 percent of adults are obese. In some ethnic groups, however, such as Hispanics and African-Americans, between 42 percent and 48 percent of the population is obese. Obesity, officially designated by the American Medical Association in 2013 as a disease, is linked to diabetes, heart disease, and cancer.

“Our findings do not necessarily relate to other soybean products like soy sauce, tofu, or soy milk, products that are largely from the water-soluble compartment of the soybean; oil, on the other hand, is from the fat-soluble compartment,” Sladek said. “More research into the amounts of linoleic acid in these products and others is needed.” Linoleic acid is an essential fatty acid. All humans and animals must obtain it from their diet.

“But just because it is essential does not necessarily mean it is good to have more of it in your diet,” Deol said. “Our bodies need just 1-to-2 percent linoleic acid from our diet, but Americans, on average, have 8-to-10 percent linoleic acid in their diets.” Deol and Sladek recommend avoiding conventional soybean oil as much as possible. “This might be difficult as conventional soybean oil is used in most restaurant cooking and found in most processed foods,” Deol said. “One advantage of Plenish is that it generates fewer trans fats than conventional soybean oil.”

“But with its effects on the liver, Plenish would still not be my first choice of an oil,” Sladek said. “Indeed, I used to use exclusively olive oil in my home, but now I substitute some of it for coconut oil. Of all the oils we have tested thus far, coconut oil produces the fewest negative metabolic effects, even though it consists nearly entirely of saturated fats. Coconut oil does increase cholesterol levels, but no more than conventional soybean oil or Plenish.”

The researchers have not examined the cardiovascular effects of coconut oil. “As a result, we do not know if the elevated cholesterol coconut oil induces is detrimental,” Sladek said. “The take-home message is that it is best not to depend on just one oil source. Different dietary oils have far reaching and complex effects on metabolism that require additional investigation.”

The study builds on an earlier study by the researchers that compared soybean oil to a high fructose diet and found soybean oil causes more obesity and diabetes than coconut oil. Next, the researchers, who found a positive correlation between oxylipins (oxidized fatty acids) in linoleic acid and obesity, plan to determine whether the oxylipins cause obesity, and, if so, by what mechanism. They will also study the effects of conventional and GM soybean oil on intestinal health.

Adapted from: Poonamjot Deol, Johannes Fahrmann, Jun Yang, Jane R. Evans, Antonia Rizo, Dmitry Grapov, Michelle Salemi, Kwanjeera Wanichthanarak, Oliver Fiehn, Brett Phinney, Bruce D. Hammock, Frances M. Sladek. Omega-6 and omega-3 oxylipins are implicated in soybean oil-induced obesity in mice. Scientific Reports, 2017; 7 (1) DOI: 10.1038/s41598-017-12624-9

Nutrition Tip of the Day

Chicken, fish and beans are good choices for protein! Remove skin and visible fat from poultry. If you do eat red meat, limit it to once in a while, keep portion size small and choose the leanest cuts.

Daily Inspiration 




The Paleo Diet

Initially thought of as a ‘good idea’ as most ideas are, the Paleo diet comes from our hunter gatherer lifestyles a very, long time ago (substantially pre-iPhone days).  Pro-Paleos argued that we as humans weren’t designed for agri-business and genetically modified foods that give us disease.  This apparently includes the humble sweet potato and whole wheat bread. They also declined to realize the human lifespan was about 20 some years old. The article from Scientific American Proponents of the Paleo diet follow a nutritional plan based on the eating habits of our ancestors in the Paleolithic period, between 2.5 million and 10,000 years ago. Before agriculture and industry, humans presumably lived as hunter–gatherers: picking berry after berry off of bushes; digging up tumescent tubers; chasing mammals to the point of exhaustion; scavenging meat, fat and organs from animals that larger predators had killed; and eventually learning to fish with lines and hooks and hunt with spears, nets, bows and arrows.”—Ferris Jabr
Currently, paleo diets aren’t really paleo.  They’re described as basically not eating: processed foods, dairy, lentils, peas, beans, peanuts.  Nuts are acceptable because they were growing to some extent 2.5 million years ago.  Basically, humans have evolved since our neanderthal days. We all have different ethnic backgrounds and can eat or digest different things.  Your Italian grandmother from Sicily might not have consumed much dairy (because there are few resources for it in southern Italy) but your Danish grandfather might have no problems with whole milk as it had been a part of their society longer.
Vegetables have evolved in several million years, check out the book Eating On The Wild Side.  Tomatoes, for instance, were more of a sad little berry than a large juicy fruit (thanks modern agriculture). Keep in mind that this diet wasn’t meant for getting every nutrient in.  You’ll have to eat a lot of greens to get calcium (if the oxaloacetic acid doesn’t suck it out first).  We also didn’t live very long 2.5 million years ago, and current hunter-gather societies today aren’t the picture of health either.