It’s finals week, and you’re staring at a mountain of assignments and study guides. Getting some sleep feels impossible as your mind races and your stomach churns. This feeling of anxiety is a part of your body’s natural stress response, driven by the hypothalamic-pituitary-adrenal (HPA) axis. This neuroendocrine system is an evolutionary response that is designed to prepare you for challenges and short-term stressful situations, but when it is activated too frequently or stays active for too long, it can disrupt your health and lead to chronic stress.
The HPA axis is comprised of three main organs: the hypothalamus, pituitary gland, and adrenal glands. Situated near the base of the brain, the hypothalamus regulates homeostatic life functions. The pituitary gland, located below the hypothalamus, is responsible for making, storing, and releasing essential hormones, like growth hormone and thyroid-stimulating hormone, which are essential for regulating growth and metabolism. The adrenal glands, which sit on the tops of your kidneys, release hormones that help control bodily functions, like our immune response, blood pressure regulation, and stress response.
In response to stress, the hypothalamus releases a hormone called corticotropin-releasing hormone (CRH). CRH then stimulates the anterior pituitary gland to release another hormone called the adrenocorticotropic hormone (ACTH). Finally, ACTH triggers the adrenal glands to release cortisol.
As the primary stress hormone, cortisol floods the body and primes it to handle stressful situations, through our “fight-or-flight” response. When cortisol is released, it impacts the body’s organs and functions by temporarily slowing our metabolism, controlling sleep/wake functions, suppressing inflammation, increasing glucose production, and storing extra energy from our food.
Regulation of the HPA axis in the body is critical, as dysfunction can become dangerous to one’s health. Chronic stress, for example, leads to the overactivation of the HPA axis and causes high levels of cortisol to stay in the body for long periods of time. This makes it harder for the body to regulate the HPA axis, and the consistently high levels of cortisol can lead to a number of health issues, such as metabolic diseases, mental health conditions, immune system dysfunction, and may even play a role in neurodegenerative conditions like Parkinson’s disease.
Parkinson’s is a progressive movement disorder caused by the death of dopaminergic neurons in the substantia nigra brain region, accompanied by an inflammatory reaction that is believed to be a contributor to its pathogenesis. During chronic stress and dysregulation of the HPA axis, cells in the brain called microglia are overactivated. These cells normally protect the brain from infection and injury, but when overactivated, they can contribute to inflammation in the brain. This excess inflammation in the brain is harmful and can contribute to neuronal damage and death, especially in areas that are more vulnerable, like the substantia nigra.
Finding healthy ways to cope with stress can be difficult for many people, but it is vital for mental and physical health. Stress can manifest itself in many ways, and can result in many physical, behavioral, and emotional changes. Some common stress signs include muscle tension, exhaustion, anxiety, irritability, digestive problems, and headaches. Recent research by Liza Varvogli and Christina Darviri shows that progressive muscle relaxation, guided imagery, diaphragmatic breathing, transcendental meditation, cognitive behavioral therapy, and emotional freedom techniques are all scientifically backed, evidence-based techniques that result in good outcomes for those who are suffering from chronic stress. By managing stress in healthy and effective ways, the HPA axis can be regulated well and help to keep the body and mind in good health.
“Finding healthy ways to cope with stress can be difficult for many people, but it is vital for mental and physical health.”