STRESS, LEARNING AND ESTRADIOL

STRESS, LEARNING AND ESTRADIOL

TUESDAY, NOVEMBER 29TH, 2011 / CHANDLER MARRS, PHD

In many ways, we assume males and females are the same, even though we know each sex has distinct and obvious differences in physiology and behavior. In the case of the stress, although the basic physiological response is comparable, the chemical reactions that the stress response elicits in males versus females are quite dissimilar. The divergent reactions are mediated by the varying concentrations of reproductive hormones that each sex is exposed to.  Far beyond just controlling sex differentiation and reproduction, sex hormones like progesterone, estradiol and testosterone modulate brain and body chemistry, quite significantly. The differences in the circulating concentrations of these hormones may account for the unequal prevalence rates of many diseases such as of depression, auto-immune disease, or migraine. These diseases are far more common in women than men.

These hormones also influence neurochemistry, and therefore, learning. In general, males and females learn quite differently from one another. Males tend to be better at spatial tasks while females tend to perform better at verbal tasks. Research suggests testosterone and estradiol may mediate those performance differences.

Estradiol also appears to affect learning under stress. When exposed to stressful conditions, male rodents learn certain classically conditioned tasks more rapidly than female rodents. However, when the female rodents’ ovaries are removed or estradiol is blocked by a drug like Tamoxifen, the difference between the two sexes is removed. That is, the female rodents acquire the conditioning as quickly and as effectively as the male rodents (Wood & Shor 1998http://www.pnas.org/content/95/7/4066).

Even though, humans are far more complicated than rodents and the controlled stress and the scope of classical conditioning tasks in the lab are limited compared to the stress and learning that takes place in the real world, it is clear that sex matters, and thus by definition, sex hormones matter.

To read more about sex differences in neurochemistry:

Chill out – prostate cancer cells thrive on stress, as do ALL cancer cells

Chill out – all cancer cells, including prostate cancer cells thrive on stress

28 January, 2013

By Staff Writer
NYR Natural News

Natural Health News — A diagnosis of prostate is a pretty stressful event.

Now a study from researchers at Wake Forest Baptist Medical Center indicates that stress is not just an emotional side effect of the diagnosis; it also can reduce the effectiveness of prostate cancer drugs and accelerate the growth of prostate cancer.

The findings are published in the February issue of the Journal of Clinical Investigation.

The  team tested the effects of behavioural stress in two different mouse models of prostate cancer.

Stress reduces effectiveness of drug therapy

One model used mice that were implanted with human prostate cancer cells and treated with a drug that is currently in clinical trial for prostate cancer treatment. When the mice were kept calm and free of stress, the drug destroyed prostate cancer cells and inhibited tumour growth. However, when the mice were stressed, the cancer cells didn’t die and the drug didn’t work.

In the second model, mice with a genetic predisposition to develop prostate cancer were used. When these mice were repeatedly stressed, the size of prostate tumours increased. When the mice were treated with bicalutamide, a drug currently used to treat prostate cancer, their prostate tumours decreased in size. However, if mice were subjected to repeated stress, the prostate tumours didn’t respond as well to the drug.

According to the researchers epinephrine, a hormone also known as adrenaline, sets off the cellular chain reaction that controls cell death. Considering that prostate cancer diagnosis increases stress and anxiety levels, stress-induced activation of the signalling pathway that turns off the cell death process may lead to a vicious cycle of stress and cancer progression.

Yet in both models in which the mice were given beta-blocker, stress did not promote prostate tumour growth. One of the actions of beta-blockers is to inhibits the activation  epinephrine.

Better ways to destress

Here’s where the researchers thinking goes a bit awry, by suggesting that beta-blockers should be supplied to prostate cancer patients to improve the effectiveness of anti-cancer therapies. Beta blockers come with a whole host of adverse effects including fatigue, stomach upset, dizziness as well as depression, shortness of breath and loss of sex drive.

Stress reduction is an important part of any kind of cancer regime – and is really best incorporated in our lifestyle before we get sick.

A study in 2006 have shown for instance that a regime of non-pharmacological stress reduction – including meditation, yoga and Tai Chi exercises – and a plant-based diet were effective in significantly reducing the PSA rate, indicating a reduction in the rate of progression of the prostate cancer.

Similar results were found in a 2011 when diet, physical activity, and stress reduction (in this case meditation) slowed prostate tumour promotion and disease progression.

Lowering levels of other stress hormones

Reducing levels of other stress hormones can be beneficial too. In one 2004 study researchers investigated the relationships between a mindfulness-based stress reduction meditation program for early stage breast and prostate cancer patients and quality of life, mood states, stress symptoms, and levels of cortisol, dehydroepiandrosterone-sulfate (DHEAS) and melatonin.

The participants were enrolled in a Mindfulness-Based Stress Reduction (MBSR) program that incorporated relaxation, meditation, gentle yoga, and daily home practice. After 8 weeks the participants experienced enhanced quality of life and decreased stress symptoms.

New Study Finds Olive Oil Effective against HER-2 Breast Cancer

New Study Finds Olive Oil Effective against HER-2 Breast Cancer

by Barbara L. Minton

(NaturalNews) Olive oil, that magical elixir from the Mediterranean, has long been known to confer many health benefits. It is one reason people who eat the Mediterranean diet live such long, healthy and happy lives. Researchers are busy scientifically documenting these benefits including recent reports on the ability of olive oil to prevent heart disease and colon cancer. The latest study shows that olive oil is effective against HER-2 positive breast cancer, a form of breast cancer for which the medical establishment offers little in the way of tolerable treatment.

Research shows polyphenols from extra virgin olive oil inhibit HER-2 activity

The December, 8 issue of the journal BMC Cancer reports researchers hypothesizing that the effects of the olive oil rich Mediterranean diet on breast cancer risk might be underestimated when it comes to HER-2 breast carcinomas. They investigated the anti HER-2 effects of phenolic fractions directly extracted from commercial extra virgin olive oil (EVOO) in cultured human breast cancer cell lines. They tested for the ability to kill both HER-2 positive and negative tumors. The effects of the EVOO fractions on the expression and activation status of HER-2 oncoprotein were evaluated.

They found that all the major EVOO polyphenols (i.e. secoiridoids and lignans) induced strong tumor killing effects by selectively triggering high levels of apoptotic cell death (programmed cell death) in cells over expressing HER-2. The EVOO polyphenols drastically depleted HER-2 protein and reduced autophosphorylation in a dose and time dependent manner. EVOO polyphenols induced HER-2 downregulation regardless of the molecular mechanism contributing to HER-2 overexpression. (i.e. naturally by gene amplification and ectopically driven by a viral promoter).

The researchers concluded that the ability of EVOO derived polyphenols to inhibit HER-2 activity by promoting the degradation of the HER-2 protein itself, together with the fact that humans have safely been ingesting polyphenols from olive oil for as long as they have been consuming olives and olive oil, support the notion that EVOO is an excellent and safe treatment targeting HER-2.

Olive oil has a long history as a healer

The health and therapeutic benefits of olive oil were first mentioned by Hippocrates, who promoted the idea that food was the best and only medicine worth using. Olive oil has contributed to the nutrition and beauty of the Mediterraneans for centuries, where it is used to maintain skin, hair, and muscle suppleness. It is a healer of abrasions, and soother of the sunburned. It has a history of external as well as internal use, and is one reason Mediterranean women have such glowing skin.

Consuming olive oil can help lower LDL cholesterol. It is rich in antioxidants that discourage artery clogging and chronic diseases involving the cardio-vascular system. People who use olive oil regularly and in place of other fats such as hydrogenated fats and vegetable oils have much lower rates of atherosclerosis, diabetes, colon cancer, and asthma.

A prospective study conducted in Florence, Italy and reported in the August, 2007 edition of the British Journal of Nutrition involved 5,611 adults 60 years or older. These adults adhered to a Mediterranean style dietary pattern characterized by high consumption of olive oil, raw vegetables, soups, and poultry. They were found to have a significantly lower rate of death from all causes in both crude and adjusted models. After 6.2 years, those most closely following an olive oil and salad dietary pattern had a 50% reduced risk of overall mortality.

In the same study people who followed another version of the Mediterranean diet based on a pasta and meat dietary pattern characterized by pasta, tomato sauce, red meat, processed meat, added animal fat, white bread and wine showed an overall mortality risk increase.

A study done in Greece and reported in March, 2007 edition of Clinical Cardiology found that relying only on olive oil may cut the risk of coronary heart disease almost in half. The study involved 700 men and 148 women with coronary heart disease along with 1078 matched controls. It looked at diet as well as alcohol intake, physical activity and smoking habits. Use of oils in daily cooking and food preparation was evaluated. After adjusting for a variety of variables, the exclusive use of olive oil was associated with a 47% lower likelihood of coronary heart disease.

People who consume 25 milliliters (about 2 tablespoons) of virgin olive oil daily for one week showed less oxidation of LDL cholesterol and higher blood levels of antioxidant compounds, especially the phenols used in the HER-2 study.

Olive oil is monounsaturated fat

There are three kinds of dietary fats: saturated fat that comes from animals and coconuts; polyunsaturated fat that comes from plants, seeds, nuts, and vegetable oil; and monounsaturated fat that comes from olive and safflower oil. Monounsaturated fats contain no cholesterol. It is not the monounsaturated fat of olive oil that conveys most of its health benefits. Instead, it is the polyphenols of olive oil that produce its remarkable benefits as was seen in the HER-2 study.

Extra virgin olive oil is well worth its cost

While all types of olive oil are sources of monounsaturated fat, extra virgin olive oil, the oil that comes from the first pressing of the olives, contains higher levels of antioxidants, particularly polyphenols and vitamin E, because it is less processed.

Generally olive oil is extracted by pressing or crushing olives. It comes in different varieties depending on the amount of pressing. These include:

Extra virgin oil - considered the best variety. It is extracted without the use of heat, and is considered a cold pressed oil. Because there is no heat or chemicals involved in its processing the flavor remains intact. As it is handled less, it retains more of its natural state.

Virgin oil - from the second pressing. It is like using a tea bag twice. The nutrients and the flavor just are not what they were the first time around.

Pure - oil has undergone some processing and heat during filtering and refining. A little extra virgin olive oil is added to this refined oil, and creates what is considered a lower grade of oil that is frequently sold under the simple term olive oil in the U.S.

Extra light - oil has undergone considerable processing and is valued by some for its lack of flavor. In this processing many nutrients are compromised. It is frequently marketed as light oil to fool you into thinking it is low fat. This type of oil is unregulated by any certification organization and there is no precedent as to what its content should be. Sometimes it has been cut with other vegetable oils.

Using olive oil

Olive oil prefers to hide its beauty. It does best when kept in a cool and dark location, in a tightly sealed bottle. This is why the really good extra virgin oils come in dark glass bottles. Like other oils, olive oil can easily become rancid when exposed to air, light or high temperatures.

The measure of an oils ability to be used in cooking is its smoke point. Once an oil begins to smoke it has lost its integrity and is producing free radicals.

Olive oil is fine for use in cooking at very low temperatures. For cooking at higher temperatures safflower oil or coconut oil are much better choices. Safflower oil, the other monosaturated oil, retains its integrity at temperatures up to 500 degrees, as does coconut oil. The flavor of safflower oil is not as delicate as that of olive oil, but when it is used in cooking other flavors usually blend well with its taste. Olive oil may be added to cooked foods when they have cooled.

Get creative with olive oil

Add olive oil to almost any cooked food after it has cooled. Use it in soups, sauces, beans, stews, and vegetable dishes. Replace vegetable oil in salad dressings and mayonnaise. Any mealtime fat can be replaced by olive oil. Put some in fresh veggie juices and smoothies. Use it in baked potatoes with herbs such asturmeric, cayenne and cumin. Add it to mashed potatoes. Warm green beans, broccoli or spinach and add olive oil and garlic. Coat cooked pasta in it. Olive oil makes a great dip for bread, especially when embellished with some oregano or thyme. Put it on air popped corn along with some sea salt and black pepper.

Use olive oil as a hair conditioner, diaper rash treatment, and skin softener. Rub it on your breasts.

Sources of information about olive oil are:

Olive Oil`s Health Benefits, healingdaily.com.

Olive Oil: Extra Virgin, whfoods.com.

Health Benefits of Olive Oil and the Mediterranean Diet, mediterraneandiet.gr.s.shtml