Cortisol Associated Diseases and Disorders
physiological functions of cortisol, one of the most vital hormones for maintaining balance in the body:
🧬 What Is Cortisol?
- Cortisol is the primary glucocorticoid hormone produced by the adrenal cortex (zona fasciculata).
- It is released in response to stress, under control of the HPA axis:
- Hypothalamus → CRH
- Pituitary → ACTH
- Adrenal glands → Cortisol
🔑 Physiological Functions of Cortisol
1. 🔄 Metabolism Regulation
Cortisol is crucial for maintaining energy balance, especially during fasting or stress:
- Increases gluconeogenesis in the liver → raises blood glucose
- Breaks down proteins (catabolism) for amino acids
- Mobilizes fats for energy (lipolysis)
- Reduces glucose uptake in peripheral tissues (insulin antagonism)
✅ Goal: Maintain blood glucose and energy during stress or fasting
2. 🛡️ Anti-Inflammatory & Immunosuppressive
Cortisol regulates immune function by:
- Inhibiting cytokine production (e.g., IL-1, IL-6, TNF-α)
- Suppressing T-cell activation and inflammation
- Reducing histamine release and stabilizing mast cells
✅ Used therapeutically as steroids (e.g., prednisone) in autoimmune or inflammatory conditions
3. 😰 Stress Response (“Fight or Flight”)
As part of the HPA axis, cortisol:
- Helps the body adapt to physical and psychological stress
- Supports cardiovascular tone, blood pressure, and alertness
- Works with adrenaline to handle acute stress
✅ Known as the “stress hormone”
4. 💧 Fluid Balance & Blood Pressure
Cortisol helps maintain vascular tone and enhances the effect of catecholamines (like norepinephrine).
- Mild mineralocorticoid activity: promotes sodium retention and potassium excretion (less than aldosterone)
✅ Supports normal blood pressure and fluid balance
5. 🧠 Mood & Cognitive Function
Cortisol receptors are found in the hippocampus, amygdala, and prefrontal cortex:
- Regulates mood, motivation, and memory
- Both low and high levels are linked to:
- Depression
- Anxiety
- Memory problems
- Sleep disturbances
6. 🦴 Bone and Skin Effects
- Inhibits bone formation (reduces osteoblast activity)
- Promotes bone resorption → prolonged excess may cause osteoporosis
- Thins the skin with prolonged high levels
7. ⏰ Circadian Rhythm
- Follows a daily cycle:
- Highest in the early morning (around 6–8 AM)
- Lowest at night (midnight)
- Regulates wakefulness and energy cycles
⚖️ Cortisol Balance is Critical
| Too Little (Adrenal insufficiency) | Too Much (Cushing’s syndrome) |
| Fatigue, low BP, hypoglycemia | Weight gain, high BP, hyperglycemia |
| Weakness, salt craving | Muscle wasting, skin thinning |
| Depression, darkening of skin (ACTH↑) | Mood swings, osteoporosis |