Stress, Hormones, and Mental Health: Understanding the HPG Axis and its Interplay with the HPA Axis

This podcast episode delves into the intricate relationship between the Hypothalamic-Pituitary-Gonadal (HPG) axis, responsible for reproduction, development, and aging, and the Hypothalamic-Pituitary-Adrenal (HPA) axis, which governs the body's stress response. Dr. Snipes emphasizes that these two systems are inextricably intertwined, profoundly impacting mental health, mood, and cognition. The discussion highlights the roles of key hormones like estrogen, progesterone, testosterone, and DHEA, explaining how their balance or imbalance directly influences neurotransmitter availability (serotonin, dopamine, norepinephrine, Gaba) and overall brain function. The episode also explores the impact of insulin sensitivity and stress on these axes, underscoring their systemic influence.

A critical distinction made is the reciprocal relationship between stress hormones and gonadal hormones: cortisol suppresses estrogen and testosterone, while estrogen and testosterone tend to suppress cortisol. This dynamic is crucial for understanding sex-specific differences in the prevalence and symptoms of affective disorders. The presentation also details the functions of individual hormones, noting estrogen's and testosterone's roles in muscle mass, fat distribution, anti-inflammatory processes, bone density, and cognitive functions. Progesterone, a precursor to cortisol, increases with stress but also possesses anxiolytic properties. The concept of "estrogen dominance" is introduced as a potential cause of mood swings, anxiety, and other symptoms, often resulting from chronic stress leading to reduced cortisol and progesterone levels.

Practical insights include the recommendation for a comprehensive blood workup for clients presenting with cognitive decline or persistent mood symptoms, as underlying hormonal imbalances may be a root cause. The episode cautions against self-supplementation of DHEA due to potential adverse effects and lack of standardization. It also highlights Polycystic Ovarian Syndrome (PCOS) not merely as a biological condition but as a potential indicator of chronic HPA and HPG axis dysregulation, often exacerbated by ongoing stress, including that stemming from adverse childhood experiences. Addressing chronic physiological and psychological stress is presented as a fundamental step in restoring hormonal balance and improving mental health.

Broader implications extend to the long-term impact of early childhood experiences, where chronic stress can permanently alter the HPA and HPG axes, affecting adult mood, reproductive desire, and susceptibility to various diseases. The podcast connects hormonal dysregulation to the development and progression of neurocognitive disorders like Alzheimer's, dementia, and Parkinson's disease, suggesting that endocrinologists may play an early diagnostic role. Furthermore, the discussion touches upon the link between hormonal health and autoimmune issues, cardiovascular health, lung function, and even certain hormone-dependent cancers, emphasizing the holistic nature of the endocrine system's influence on overall well-being and the neuroprotective role of sex hormones.

The hpg axis has been implicated in the development of psychiatric conditions such as mood anxiety and cognitive disorders.

Remember the HPA axis is our stress response system and the hpg axis is more than but we think about it in terms of our reproduction and development system but they all work together.

cortisol our main stress hormone suppresses estrogen and testosterone and estrogen and testosterone tend to suppress cortisol so they work against each other.

alterations in maternal care... can produce significant effects on both the hpg and HPA physiology as well as behavior in The Offspring at adulthood.

when a child experiences adverse childhood experiences... that ongoing chronic stress can alter the HPA axis even you know as young as infancy and they've shown that the alterations in in maternal care not only impact the HPA axis... but also it impacts the hpg axis.

estrogen increases serotonin and serotonin receptors in the brain and modulates higher order cognitive processes that are driven by dopamine such as learning reward processing working memory and impulse control.

stress suppresses estrogen and testosterone.

PCOS is an indication of norepinephrine and the ovaries cystic development in the ovaries which is an indication of some other pathology that may be causing that including including chronic stress and stress that may be continuing to be carried as a result of adverse childhood experiences.

men and women with Alzheimer's disease anxiety depression and other neurocognitive or mental health issues have been found to have lower levels of depending on the gender testosterone or estrogen than those without neurocognitive or mental health issues.

our sex hormones are actually very neuroprotective and if we start losing them... we lose that neuroprotective factor.

oxidative stress is now recognized as a central contributor to the development of many different disorders including PCOS and Neuropsychiatric disorders including anxiety and depression.

people with diabetes tend to have... they tend to be more insulin resistant and they tend to have lower levels of testosterone or or estrogen.