Cortisol-3 [AP]

Cortisol is a glucocorticoid hormone produced by the adrenal cortex that is largely responsible for metabolic regulation, immunological response, and stress management. Cortisol, the ultimate output of the hypothalamic-pituitary-adrenal (HPA) axis, regulates blood glucose levels, lipid metabolism, immunological function, and inflammatory reactions. The HPA axis is a complicated neuroendocrine system that regulates glucocorticoid secretion via feedforward and feedback loops, maintaining a balance between physiological homeostasis and stress reactivity. The HPA axis' activity is affected by circadian rhythms, environmental stress, and other internal and external factors. This regulating ability enables cortisol to adapt promptly to varied stressors, thereby protecting the body from harm.

However, disrupting the control of the HPA axis can result in the development of a variety of disorders, including metabolic syndrome (MetS) and major depressive disorder. Metabolic syndrome is a collection of cardiometabolic disorders that includes abdominal obesity, hypertension, hyperglycemia, and dyslipidemia, all of which are major risk factors for type 2 diabetes and cardiovascular disease. According to research, overactivation of the HPA axis, which results in excessive cortisol release, is a major contributor to the development of MetS. High cortisol levels promote fat synthesis while inhibiting insulin action, resulting in insulin resistance and hyperglycemia. These metabolic anomalies accelerate the evolution of MetS, resulting in a vicious cycle. Cortisol is also known to be intimately associated with the onset and development of severe depressive illness. MDD is a widespread mental condition with a complex and poorly understood pathophysiology. The dysfunction of the HPA axis is a well-studied topic. According to research, MDD patients frequently demonstrate HPA axis hyperreactivity, as seen by higher baseline cortisol levels, particularly the cortisol awakening response (CAR) in the morning. CAR is the quick rise in cortisol levels upon waking, which may be connected with arousal, energy surge, and readiness for daily stress. For MDD patients, an aberrant rise in CAR is thought to be associated with the severity of depressive symptoms, particularly morning mood depression and fatigue.

Figure 1. Schematic of the HPA Axis and the Circadian Rhythm of Cortisol/Corticosterone in Humans and Rats over 24 Hours (Source: Lightman SL, et al., 2020)

In addition to its relationship with metabolic syndrome and major depressive disorder, cortisol testing has also become a research focus in recent years. Traditionally, cortisol measurement has been conducted using blood, urine, and saliva samples, but these methods only reflect short-term cortisol levels. Recently, hair cortisol concentration (HCC) measurement has emerged as a new research tool, offering the unique advantage of providing a retrospective assessment of long-term cortisol secretion. HCC reflects cortisol levels over several months, and sample collection is relatively simple and convenient for storage. Therefore, HCC is considered a powerful tool for assessing chronic stress and its related health risks, with significant potential applications in mental health research. Hair cortisol concentration, unlike traditional biological samples, is not greatly impacted by circadian rhythms, alcohol consumption, contraception usage, or other circumstances, making assessment results more stable and trustworthy. In summary, cortisol has a major role in the control of immunity, metabolism, and mental health and is a major stress hormone. We can gain a deeper understanding of the processes by which cortisol plays a role in the development of disorders like major depressive disorder and metabolic syndrome by conducting extensive studies on the HPA axis. Furthermore, more data will be accessible to assist the future diagnosis and prevention of these disorders because of advancements in detection technology, such as the creation of hair cortisol testing.

Cortisol-3 Conjugate [AP]
Cortisol-3 Enzyme Conjugate [AP]
Cortisol-3 [Alkaline Phosphatase Conjugate]
Cortisol-3 [AP] ELISA Conjugate