Plants, Genes and Health: a Growing Connection

Juvenon Health Journal volume 10 number 12 February 2012

By Benjamin V. Treadwell, Ph.D.

What if you could tune your body, like a mechanic tunes a race car, to achieve maximum performance/health?

This is not just a fantasy, even though the human body is far more complex than an automobile engine. But thanks to recent advances in analytical technology and nutrition, medical research is getting closer to making “fine-tuning” the body’s biochemical reactions a reality.

These reactions aren’t isolated. The cells, tissues, and organs of our bodies are interconnected via hormones and numerous additional metabolic regulators. The healthy body requires a balance between the regulators, maintained by specific signals and governed by gene expression.

Unfortunately, highly tuned regulations in the body can become dysfunctional.  This imbalance leads to reduced energy and health problems. Here’s where a genetic tune-up could help. It’s also where diet, especially plant nutrients (like fisetin, discussed in our last Health Journal), can make a difference. And it’s where a new concept – nutrigenomics – comes in.

Diet, DNA and Deer

Consider the role a deer’s genetic make-up plays in its ability to metabolize available food. The animal forages on a variety of plants, which differ greatly from season to season. In late fall, when some plants become scarce, the deer eats less, switching to a diet of woody stems, roots and evergreens.

How does the deer thrive on this lower-calorie menu? Research indicates the animal’s limited, available-food diet modulates its metabolism. How does the deer know when to stop eating leaves and start eating woody stems? The deer does not need to be conscious of the coming seasons and their associated foods. The information is built into its genes. Among the variety of nutrients contained in each food type, some are recognized by cell sensors that bind to the nutrient. The nutrient-bound sensor, in turn, functions as a messenger to alert the cell of a change in diet. The cell makes the necessary adjustments to produce the tools (enzymes) required to process the twigs, roots and evergreens for energy.

This explains why providing grain for deer in the winter months may actually harm rather than help them. A plentiful food supply causes the deer’s winter-tuned metabolism to revert to summer regulations. If the grain becomes unavailable, the deer will actually starve. Their metabolism cannot adapt quickly enough to the much more difficult-to-digest, naturally available foods.

Genes + Nutrients = Nutrigenomics
This interaction between specific dietary nutrients and the genes involved in regulating metabolism is evident in humans as well as animals. It affects everything from brain function and memory, to bones, to the immune system. It is the essence of one of the newest fields of medicine, nutrigenomics.

Nutrigenomic studies underscore the importance of including plants in our diet. Their nutrients are critical for optimal regulation of gene expression, maintaining our health, both physical and mental.

Plant Nutrients for a Healthy Gut

A recent study of immune intestinal structures supports the need to “eat right” (sufficient plant nutrients) for healthy development, too. (See this issue’s “Research Update.”)

The digestive system is exposed to toxic substances from the pathogenic bacteria it harbors, as well as the environment (pesticides, etc.)  in one study, researchers identified the aryl hydrocarbon receptor (AhR) cellular component as key to neutralizing the toxins. The research team confirmed that mice lacking these receptors had deficient intestinal immunity. The subjects showed symptoms of inflammatory bowel disease and increased susceptibility to cancer.

Next, the investigators set out to prove the AhRs are required not only for protection, but also to trigger the normal development of a robust immune system, at least in mouse gut tissue. They were interested, too, in whether phytochemicals (plant nutrients), binding to this receptor, are involved.

One plant nutrient, indol-3-carbinol, is present in cruciferous vegetables such as broccoli. Adding this phytochemical to the mouse chow and fed to the mice for several weeks, resulted in the presence of additional specialized immune structures within the lining of the intestines. Meanwhile, the control animals, who did not eat the phytochemicals, showed an almost complete absence of the immune intestinal structures required for a healthy, disease-free digestive system.

Part Plant

The deer and mice data paint a picture of an animal kingdom continuing to rely on the plant world for a healthy existence. It seems we are consuming plants for more than food (fat, carbohydrates, protein, vitamins) and energy, though.

The co-evolution of animal and plant left an indelible imprint. During the process, the pre-animal was basically part plant. It depended on them to supply nutrients supporting its growth and development, sharing genes and gene products. In fact, it’s likely some of the genes and regulators of metabolic pathways involved in plant defense were “hijacked” and incorporated into the genome of the evolving animal.

In fact, there are numerous examples of phytochemicals that function as immune enhancers, both for the plant manufacturing them and the animal consuming the plant. Indol-3-carbinol, already mentioned, is one example. Other plant nutrients, which ward off predators and pathogens, also contribute to immune defenses for herbivores and omnivores.

It seems the paradigm of animal dependence on plants is expanding. A veritable “flood” of recent studies has shown multiple effects of a variety of plant nutrients, which may help to promote more youthful health for both body and mind.

Personal Plants

Plants seem to be winning the species survival game. The shrewd animal helps assure their continued existence, not only because they provide sustenance, but also due to the health benefits they initiate as part of the animal diet.

Recent discoveries about how that happens (nutrigenomics) have led to an explosion of ideas on improving health with diet on a case-by-case basis. After all, we are genetically diverse. The differences may be small in terms of percentage, but they seem to have dramatic effects on which nutrients we need and how much of them.

In the not too distant future, nutrigenomics will develop laboratory tests capable of determining each person’s optimum combination/intake of nutrients to maintain maximum health and vitality. Of course, there’s still a lot of work to be done to make this level of “personalized medicine” practical and affordable. Until then, consuming a variety of plants and/or supplements containing plant nutrients is the next best thing.

Dr. Treadwell
answers your questions.

question:  Recently, there have been articles saying that we don’t need to be taking vitamins in addition to a balanced diet. What do you think? After just reading the e-mail that you sent, I can imagine that would not be your position, especially as we all age. I’m looking squarely at 60! Thanks — A

answer: I think it’s fair to say that at least some of us may need more nutrition than our diet is providing. The evidence in support of taking vitamins and nutritional supplements for optimal health seems substantial.

For every article reporting little or no positive effect from supplementing with vitamins, there are even more studies demonstrating the complete opposite, conducted by laboratories around the world. In practice, health professionals routinely order tests to monitor blood levels of vitamins and minerals, then recommend health supplements as indicated.

Factors other than an “unbalanced” diet can also cause deficiencies. As you mentioned, they include aging. Older people, for example, are often deficient in Vitamin B-12. Peer-reviewed research indicates they may benefit from supplementing. Research has connected low levels of B-12 to senior health concerns like atherosclerosis and neurodegenerative conditions such as Alzheimer’s disease.

Recently, you may have also read about the “dangers” of some vitamins. One seems to contribute to cardiovascular disease, while another may increase the incidence of stroke. Pretty shocking until you realize that flawed experimental protocols or uneducated interpretations are often behind these kinds of conclusions.

In other words, it’s best to take what you see in the media with a grain of salt (unless you’re hypertensive). Hedge your bets with exercise and a healthy diet of fruits, vegetables, legumes, fish, olive oil, and a minimum of high-fat, high-sugar, low-food-value choices.

When selecting supplements, be skeptical. Rely on trusted sources, including your health professional. And keep in mind that genetics, as well as stress, also contribute to your vitamin needs. These factors vary from person to person, making it nearly impossible to prescribe a vitamin (or no-vitamin) regimen that applies to everyone.

No wonder the RDA is in constant flux! Current and future research will provide us with the tools to examine parameters of health on a more personal level, allowing for nutrient recommendations tailored to the individual.

Dr. Benjamin V. Treadwell is a former Harvard Medical School professor and member of Juvenon’s Scientific Advisory Board.

After identifying a small molecule in strawberries that may help maintain aging brain function on multiple levels, investigators from the Salk Institute for Biological Sciences in La Jolla, CA examined this molecules effects in mice and rats. Their findings appeared in a Genes & Nutrition article: “Modulation of multiple pathways involved in the maintenance of neuronal function during aging by fisetin.”

Fisetin, is a plant flavonoid, found at highest concentrations in strawberries. Fisetin acts directly as an antioxidant, helping maintain mitochondrial function in the presence of oxidative stress. It can increase the levels of a major intracellular antioxidant, glutathione, and also acts as an anti-inflammatory.

To determine how fisetin may help reduce age-related learning and memory deficits, the research team conducted rodent model experiments. In one study, they fed half a group of mice food containing fisetin and the other half (the controls) the same food without the flavonoid.

The two groups navigated a water maze with a submerged “rest” platform that would allow them to avoid becoming exhausted from swimming. There were visual cues to help them find it. The time it took each mouse to locate the platform was recorded.

To measure learning, both groups ran the water maze again 24 hours later. The fisetin-fed group was much faster than the controls, finding the platform in half their original times. In other words, they demonstrated a significant advantage in their ability to remember/learn.

Intrigued by what seemed to be a fisetin-induced improvement in learning ability, the researchers designed another experiment to help determine the mechanism(s) behind it. This time the study focused on the memory center of the brain, the hippocampus. The investigators hypothesized that fisetin facilitates the molecular basis for learning and memory: long-term potentiation (LTP).

LTP is the term for helping two neurons transmit electrical charges and improving sensitivity to electrical stimuli. A strong external stimulus improves the synapse’s strength, sensitizing it to a full response with subsequently less intense stimuli. This effect can last for a long period of time, hence long-term potentiation.

To test their theory, the research team incubated sections of tissue from the rats’ hippocampi in a medium with or without (control) fisetin. They stimulated the sections with electrical pulses and recorded the responses. The hippocampal tissue incubated in the presence of fisetin was more responsive to minimal electrical stimulation than the control tissue.

The results support the team’s hypothesis. They demonstrate that fisetin increases the sensitivity of the biochemical pathways involved in inducing the memory-important brain activity, LTP. (Additional studies by this group have also shown that fisetin acts on multiple biochemical pathways to improve brain health and function.)

Read abstract Here

This Research Update column highlights articles related to recent scientific inquiry into the process of human aging. It is not intended to promote any specific ingredient, regimen, or use and should not be construed as evidence of the safety, effectiveness, or intended uses of the Juvenon product. The Juvenon label should be consulted for intended uses and appropriate directions for use of the product.