Have you ever gone through a long period of extreme stress, such as a divorce, losing a loved one, or a period of financial struggle? Did you notice how your body reacted to it? You may have found yourself eating more than usual, maybe you felt really exhausted, or maybe you felt “totally stressed out” and more anxious than usual. Any and all of those reactions are perfectly normal, because for most of us, stress causes a biochemical reaction in our endocrine and nervous system, leading to a disruption in the normal patterns of chemicals that our body relies on to feel balanced.
The interesting thing is that we don’t all have exactly the same reactions to stress. Some people tend to eat more, some people completely lose their appetite. Some people can handle excess stress without getting anxious, and some people are extremely sensitive to it. Like snowflakes, we all have our own unique biochemical individuality.
Scientists are extremely interested in learning more about how our endocrine and nervous system creates chemical messengers in reaction to stress. By understanding this better, drugs can be developed to manipulate biochemistry and potentially treat stress related problems like anxiety, depression and obesity. These have become very prevalent and concerning problems because they can lead to more serious conditions over time, and so far, have not been easily treatable.
The roles of the endocrine and nervous system are to produce many different chemicals to keep body systems in balance. One of the chemical messengers secreted by the nervous system that deserves attention is neuropeptide Y (NPY). NPY is the most abundant neuropeptide in the brain. Neuropeptides are small protein-like molecules (peptides) used by neurons (nervous cells) to communicate with each other. NPY seems to have many balancing roles, such as moderating appetite depending on conditions (high or low blood sugar) and using or conserving energy as needed. It also interacts with the endocrine system, as some studies suggest NPY suppresses cortisol (the stress hormone) secretion. NPY is secreted during times of stress to help our resiliency to stress. This means that people with healthy doses of NPY can handle bigger challenges without feeling “stressed out” and may in part explain our biochemical individuality.
Scientists don’t fully understand NPY yet, but clinical studies have indicated that people with major depression and anxiety have lower levels of NPY. Animal studies show that when scientists block NPY, animals exhibit more stress-out behaviors, one being higher alcohol intake. And animals with the highest levels of NPY show no behavioral response to stress. Overall, it appears that NPY acts a valuable buffer against the ravages of stress. Researchers in pharmaceutical companies are working to develop a drug that duplicates NPY or acts on NPY receptors in the body, to treat people with anxiety, depression or obesity.
So naturally I found it interesting to read a study that found that adaptogenic herbs herbs enhance the beneficial effects of NPY. That helps us better understand why adaptogens are helpful to counteract the effect of stress. An in vitro study, meaning a cell study in a test tube, showed that three adaptogenic herbs, Eleuthero, Rhodiola, and Schizandra increased nerve cells secretion of NPY. The bigger the dose of adaptogens, the more NPY was secreted.
What fascinates me about herbs is that unlike pharmaceutical drugs, which usually have one specific (and strong) action, herbs offer a variety of phytochemical compounds with different functions. Plants are complex and have a broad variety of actions, but they are usually more gentle and balanced with less side effects. Test tube studies are a good way to isolate active constituents from an herb and examine how they work on specific cells. This study is useful because it singled out the neuropeptide NPY and measured how adaptogens effect it. There are also clinical studies on people that show how adaptogens help with endurance, fatigue and mood.
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