Hormones and blood

Nut Cereal

There are many hormones that assist in the production of blood cells and platelets, regulating blood pressure, protection of blood cells and blood clotting.  Where a patient has constant issues with blood pressure or keeping adequate levels of iron, analysis of hormones should be considered.

Erythropoietin (EPO, haematopoietin or haemopoietin)

Erythropoietin is produced mainly in the kidney, by interstitial cells.  Once the hormone is made it protects red blood cells against destruction.  It also stimulates stem cells of the bone marrow to increase the production of red blood cells.

Angiotensin

Angiotensin is a hormone that helps regulate your blood pressure by constricting (narrowing) blood vessels and triggering water and sodium intake.  Angiotensin is part of linked hormones, enzymes, proteins and reactions called the renin-angiotensin-aldosterone system.

There are four different forms of angiotensin: Angiotensin I–IV.  Angiotensin II is the main and active form of the hormone.  If your body has too little or too much angiotensin, it can cause health issues.

Angiotensin II binds to several receptors and affects many different systems and functions, including:

  • Stimulating the release of aldosterone from your adrenal glands, which causes your body to retain sodium and lose potassium through your urine.
  • Increasing blood pressure by narrowing blood vessels.
  • Triggering the sensation of thirst through your hypothalamus.
  • Triggering the desire for sodium through your hypothalamus.
  • Stimulating the release of antidiuretic hormone from your pituitary gland, which causes your kidneys to reabsorb water. (1)

Thrombopoietin

Thrombopoietin is the chemical mediator that regulates the number of platelets in the blood by stimulating an increase in the number and growth of megakaryocytes, thus controlling the rate of platelet production.

Vasopressin

Vasopressin is known as an antidiuretic hormone.  It maintains the appropriate volume of water in the space that surrounds cells within the body.  It plays a role in regulating circadian rhythm, maintains the body’s internal temperature, blood volume and the proper flow of urine from the kidneys.  Nerve cells at the base of the brain (hypothalamus) make and transport vasopressin to the pituitary gland, which then releases the hormone into the bloodstream  If your body produces too much vasopressin, your kidneys may retain water.  If you don’t have enough vasopressin, your kidneys may excrete too much water.  This causes frequent urination and can lead to dehydration, as well as low blood pressure. (2)

Aldosterone

Aldosterone is a steroid hormone produced by the adrenal glands.  It supports the regulation of blood pressure mainly by acting on organs such as the kidney and the colon to increase the amount of sodium reabsorbed into the bloodstream and to increase the amount of potassium excreted in the urine.  Aldosterone also causes water to be reabsorbed along with sodium; this increases blood volume and therefore blood pressure. (3)

Hepcidin

Hepcidin is a peptide hormone produced in the liver that plays a crucial role in iron production and uptake.  Serum iron levels must be tightly regulated to ensure an adequate supply is available for hemoglobin synthesis, without allowing iron overload to occur in the body.  Hepcidin decreases the level of iron by reducing dietary absorption and inhibiting iron release from cellular storage.  Too much hepcidin can lead to problems like iron deficiency, where your body doesn’t absorb enough iron.  Too little hepcidin can cause iron overload, where your body absorbs too much.

Prostaglandins

Most hormones are produced by glands and transported in the bloodstream.  Prostaglandins are produced at the site where they are needed, are produced in nearly all body cells and are part of the body’s way of dealing with injury and illness, where there is inflammation, pain and fever.  When a blood vessel is injured, a prostaglandin called thromboxane stimulates the formation of a blood clot; a muscle in the blood vessel wall contracts to try to prevent blood loss.  Another prostaglandin called prostacyclin has the opposite effect to thromboxane, reducing blood clotting and removing any clots that are no longer needed and causing the muscle in the blood vessel wall to relax.  The opposing effects that thromboxane and prostacyclin have on the blood vessels can control the amount of blood flow and regulate response to injury and inflammation. (4)

References:
  1. Professional, C. C. M. (n.d.-a). Angiotensin. Cleveland Clinic. https://my.clevelandclinic.org/health/articles/23359-angiotensin
  2. Cassata, C. (2023, September 22). What is vasopressin? EverydayHealth.com. https://www.everydayhealth.com/vasopressin/guide/
  3. Aldosterone | You and Your Hormones from the Society for Endocrinology. (n.d.). https://www.yourhormones.info/hormones/aldosterone
  4. Prostaglandins | You and Your Hormones from the Society for Endocrinology. (n.d.). https://www.yourhormones.info/hormones/prostaglandins/

 

 

 

Hormones involved in Digestion

gut health

The gut is a major producer of hormones, with more than 20 known hormones being responsible for controlling food intake, digestion of food, energy expenditure and influence the pleasure of eating.  Some of these digestive hormones target the brain and work in association with the enteric nervous system and is often why the gut is known as the “2nd brain”.

Some of the well known hormones are below:

Gastrin

Gastrin is a hormone that is produced in the lining of the stomach and upper small intestine and is released into the bloodstream.  During a meal, gastrin stimulates the stomach to release hydrochloric acid, which then allows the stomach to break down food and absorb certain vitamins such as vitamin B12.  Gastric acid also acts as a disinfectant.  Gastrin can stimulate the gallbladder to empty its store of bile and the pancreas to secrete enzymes.  Gastrin also stimulates growth of the stomach lining and increases the muscle contractions of the gut to aid digestion. (1)

Ghrelin

Ghrelin is a hormone that is produced and released mainly by the stomach with small amounts also released by the small intestine, pancreas and brain.  It is known as the ‘hunger hormone’ because it stimulates appetite, increases food intake and promotes fat storage.  Ghrelin levels are actually higher in people with lean body weight compared to those who are overweight.  High levels of Ghrelin have also been found in people with certain cancers, anorexia nervosa and cachexia. (2)

Glucagon

Glucagon is made by the pancreas and helps regulate your blood glucose (sugar) levels.  Glucagon increases your blood sugar level and prevents it from dropping too low, whereas insulin, another hormone, decreases blood sugar levels.

Insulin

Insulin is released from the Pancreas and is essential for helping your body use glucose for energy.  If your body cannot produce enough insulin, or your body cannot use the insulin being released, it causes high blood sugar levels.  In most people insulin lowers blood sugar levels, stimulates metabolism of glucose, protein, and fat.  The inability to produce insulin by destruction of beta cells in the pancreas, creates an autoimmune condition which results in Type 1 Diabetes Mellitus and those diagnosed require injections of insulin for the rest of their lives.  Type 2 Diabetes Mellitus is when the body cannot properly use insulin, and is often a result of poor eating and lifestyle habits which results in insulin resistance. (3) (4)

Insulin-like growth factor (IGF-1)

IGF is a hormone that your body makes naturally in the liver and acts much like insulin.  It used to be known as somatomedin.   IGF helps to control growth hormone secretion in the pituitary gland.  IGF works with growth hormones to promote growth and development of bone and tissue.  These hormones also affect how your body metabolizes sugar, or glucose.  IGF and insulin can work together to rapidly reduce the level of glucose in your blood.

Leptin

Leptin is a hormone released by body fat that helps your body maintain normal weight on a long-term basis.  It does this by regulating hunger by providing the sensation of satiety (feeling full).  As leptin is created by stored body fat, the higher level of body fat means a higher release of leptin.  This signal should mean that the person stops eating.  For those on weight loss protocols, as your body fat decreases, your leptin levels decrease, which may signal your body to think that it is suddenly in starvation, which it clearly is not.  This feeling of starvation can stimulate hunger and appetite and can lead to increased food consumption.  (5)

Gastric Inhibitory Peptide (GIP)

GIP is a member of the secretin family of hormones.  It was discovered in extracts of intestine that inhibited gastric motility and secretion of acid, and initially called enterogastrone.  It is secreted from mucosal epithelial cells in the first part of the small intestine.

GIP enhances the release of insulin in response to infusions of glucose.  For this action, it has also been referred to as glucose-dependent insulinotropic peptide.

Secretin

Secretin is a digestive hormone secreted by the wall of the upper part of the small intestine (the duodenum) that regulates gastric acid secretion and pH levels in the duodenum.  When hydrochloric acid passes from the stomach into the duodenum, secretin is released into the bloodstream and stimulates the duct cells of the pancreas to secrete water and bicarbonate.  By this mechanism, hydrochloric acid secreted by the stomach is diluted and neutralized.  Secretin also inhibits the secretion of gastrin, which triggers the initial release of hydrochloric acid into the stomach, and delays gastric emptying. (6)

References

  1. Gastrin | You and Your Hormones from the Society for Endocrinology. (n.d.). https://www.yourhormones.info/hormones/gastrin/
  2. Ghrelin | You and Your Hormones from the Society for Endocrinology. (n.d.). https://www.yourhormones.info/hormones/ghrelin/
  3. (2023, December 6). Type 1 diabetes | Diabetes Australia | Diabetes Australia. Diabetes Australia. https://www.diabetesaustralia.com.au/about-diabetes/type-1-diabetes/
  4. Healthdirect Australia. (2021, November 4). Type 2 diabetes. https://www.healthdirect.gov.au/type-2-diabetes
  5. Professional, C. C. M. (n.d.-d). Leptin & Leptin Resistance. Cleveland Clinic. https://my.clevelandclinic.org/health/articles/22446-leptin
  6. Utiger, R. D. (1998, July 20). Secretin | Definition & Function. Encyclopedia Britannica. https://www.britannica.com/science/secretin

 

 

Hormones and Mood

Healthy foods

Many hormones affect your mood, emotions, behaviour and personality.  Certain hormones are associated with specific traits such as depression and happiness, and due to the fluctuations of hormones and the overall health of people, these traits change from person to person.  Hormones can spike dramatically during periods of major life changes, such as after child birth, children beginning puberty, death of a family member or divorce.

Dopamine

This neurotransmitter is also a neurohormone related to the hypothalamus, and one of its main function as a hormone, is to inhibit the release of prolactin and to act in cells in the brain to give you feelings of pleasure, motivation and satisfaction.  Dopamine also controls memory, sleep, learning, concentration and mood.  When you do something fun, you have an increase of dopamine in the brain.  This can also occur when you drink alcohol or use illegal drugs which can lead to addiction.

Dopamine also controls body movements and low levels have been associated with Parkinson’s Disease.  Low levels are also found in people with ADHD.  An imbalance of dopamine can cause mental illness such as depression and schizophrenia.

Dopamine is derived from amino acids, specifically tyrosine which occurs naturally in foods such as nuts, eggs, seeds, dairy and meat.

Melatonin

Released from the Pineal gland, Melatonin is an antioxidant hormone and is important in regulating the circadian rhythm (sleep/wake cycle).  Circadian rhythm is the physical, mental and behavioural changes that follow a 24-hour cycle and respond primarily to light (day light) and dark (night time).

Researchers have also found that Melatonin helps in regulating female hormones and the menstrual cycle.  Melatonin released by the pineal gland (not supplements) helps protect against neurodegeneration (loss of function of neurons) and can cause conditions such as Alzheimer’s and Parkinson’s.  Melatonin supplementation is also being used as an extra treatment for women with breast cancer.

Serotonin

Also known as 5-hydroxytryptamine (5-HT), serotonin is a hormone and a monoamine neurotransmitter.  Serotonin carries messages between the central nervous system in your brain and throughout your body via your peripheral nervous system.  Around 90% of serotonin is made in the gut lining and 10% is produced by the brain.  It is released into the blood stream where it is absorbed by platelets.

Serotonin assists in learning, memory, happiness, regulating body temperature, sleep, sexual behaviour and hunger.  Low levels are related to depressive mood, anxiety and other mental health conditions.

Serotonin is a product of the essential amino acid tryptophan, which isn’t produced by the body, but ingested via foods such as chicken, cheese, fish, peanuts and turkey.

Adrenaline (or epinephrine)

Naturally released from the Adrenal Gland (which sits on the top of each kidney), following a message from the brain that you are facing a stressful, exciting or dangerous situation.  Adrenaline is a hormone that causes your heart rate to increase, your breathing rate to increase, increase in blood pressure and a rise in blood sugar which gives you energy.  This is known as a ‘fight or flight’ response.  Adrenaline is also a medication that is used to treat anaphylaxis. (1)

Norepinephrine (or noradrenaline)

Norepinephrine is both a hormone and a neurotransmitter.  Norepinephrine is produced within the inner adrenal medulla.  Norepinephrine helps the body respond to stress and exercise, it plays a role in your mood and ability to concentrate, it increases heart rate, increases blood pressure, breaks down fat and increases blood sugar levels.  Low levels can cause lethargy, lack of concentration, ADHD symptoms and possibly depression. (2)

Corticoliberin (Corticotropin-releasing factor (CRF), also termed corticotropin-releasing hormone (CRH))

Corticoliberin is a corticotropin-releasing polypeptide hormone.  It is also a neurotransmitter involved in the response to internal or external stresses.  CRF regulates adrenal function indirectly through the central nervous system (CNS) via the hypothalamic-pituitary-adrenal (HPA) axis and via the autonomic nervous system by way of locus coeruleus (LC) in the brain stem. (3)

Orexin

Orexin is a neuropeptide hormone, also known as hypocretins, produced in the hypothalamus.  Orexins bind and activate two G-protein–coupled receptors (GPCRs), orexin receptor type 1 (OX1R) and type 2 (OX2R).  Orexin/receptor pathways play vital regulatory roles in feeding behaviour, sleep–wake rhythm, reward and addiction and energy balance.  Several studies have shown that orexin/receptor pathways are involved in pathological processes of neurological diseases such as narcolepsy, depression, ischemic stroke, drug addiction and Alzheimer’s disease.

Oxytocin

Oxytocin is a peptide hormone and neuropeptide produced in the hypothalamus and released by the posterior pituitary.  The two main physical functions of oxytocin are to stimulate uterine contractions in labour and childbirth and to stimulate contractions of breast tissue to aid in lactation after childbirth.  During labour, when the fetus’s body pushes against the cervix, the nerve impulses travel to your brain and stimulate your pituitary gland to release oxytocin into your bloodstream.  The oxytocin travels to your uterus and stimulates contractions.  Once the baby is born, oxytocin promotes lactation by causing contractions of the myoepithelial cells in the alveolar ducts of the breasts.  These contractions move milk through your breast tissue.  In males oxytocin plays a part in ejaculation.  The hormone contracts the vas deferens to push sperm and semen forward for ejection.  Oxytocin also affects the production of testosterone in the testes.  (4)

You might know Oxytocin by one of its other names: the love hormone or bonding hormone.  Oxytocin plays an important part in human bonding.  Released during childbirth and breastfeeding, it’s a key factor in the bond between parent and infant.  Hugging, kissing, cuddling and sexual intimacy can all trigger oxytocin production, which can strengthen bonds between adults.

Cortisol

Cortisol is a glucocorticoid (steroid) hormone produced by the adrenal glands.  This hormone regulates the body’s stress response, helps control your body’s use of fats, proteins and carbohydrates (metabolism), suppresses inflammation, regulates blood pressure, regulates blood sugar, and helps control the sleep-wake cycle.  Your body releases cortisol when it has any type of stress, whether it is physical or mental stress.  Cortisol will release adrenaline when a person needs to be on high alert and releases glucose when fast energy is required (ie. to run away from danger).  Normally cortisol would be low in the evening and high in the  mornings.  Cortisol counterbalances the effects of insulin.  Having chronically high cortisol can lead to high levels of blood sugar.  (6)

 

References:
  1. Healthdirect Australia. (2023, October 17). Adrenaline. Healthdirect. https://www.healthdirect.gov.au/adrenaline
  2. Society, E. (2023, January 5). Adrenal hormones. Endocrine Society. https://www.endocrine.org/patient-engagement/endocrine-library/hormones-and-endocrine-function/adrenal-hormones
  3. Tsatsanis, C., Dermitzaki, E., Venihaki, M., Chatzaki, Ε., Minas, V., Gravanis, A., & Margioris, A. N. (2007). The corticotropin-releasing factor (CRF) family of peptides as local modulators of adrenal function. Cellular and Molecular Life Sciences, 64(13), 1638–1655. https://doi.org/10.1007/s00018-007-6555-7
  4. Professional, C. C. M. (n.d.-f). Oxytocin. Cleveland Clinic. https://my.clevelandclinic.org/health/articles/22618-oxytocin
  5. Professional, C. C. M. (n.d.-b). Cortisol. Cleveland Clinic. https://my.clevelandclinic.org/health/articles/22187-cortisol