Hormones and their role in the human body

Hormones

Hormones are chemical transmitters released directly into the bloodstream, which is carried to organs and tissues of the body to perform specific functions. Different hormones work on different parts of the body to perform different functions.

Types of Hormones

Hormones are of three types:

• Lipid-derived
• amino acid-derived
• peptide

Lipid-derived hormones 

As the name suggests, these hormones are derived from cholesterol, they are structurally similar to fatty acid. Lipid hormones are introduced in humans as Steroid hormones. Functional groups like alcohol and ketones form these categories of hormones. Examples include estrogen, aldosterone, testosterone and cortisol. These hormones are water-insoluble and are transported by proteins found in the blood.

Hence they remain in circulation for a longer period than peptide hormones.

Amino-acid derived hormones

Hormones derived from amino acids are smaller molecules. They are derived from amino acid-like tyrosine and tryptophan. The amino acid-derived hormones have “one” at the end of their chemical names. Examples of amino acid-derived hormones are thyroxine, which is produced by the thyroid gland, norepinephrine, which is synthesized in the medulla of the adrenal gland, and epinephrine. The pineal gland in the brain on the other hand produces and perspires melatonin, which helps in coordinating the sleep cycle.

Peptides 

The peptide hormones consist of a polypeptide chain. To be more precise, short polypeptide chains are found in these hormones. Antidiuretic hormone and oxytocin made in the posterior pituitary gland of the CNS are discharged into the bloodstream. This category is composed of small proteins like growth hormone(formed by the pituitary gland), and large size glycoproteins which include FSH(follicle-stimulating hormone). Released peptide hormones are kept in vesicles of cells that synthesize them.

It is released in response to a stimulus which includes a rise in glucose level when insulin is released. They are insoluble in lipids but soluble in water. Therefore, they cannot cross through the plasma membranes of cells and have their receptors found on the target cell’s surface.

Important hormones and their functions

Estrogen 

Estrogen is one of the most important female sex hormones, but men also produce estrogen, although in smaller amounts. Estrogen is produced in the ovaries and is involved in ovulation, breast maturation, menstruation, and bone and cartilage density growth in women.

Too much estrogen can raise the threat of cancers and are linked to symptoms like weight gain, depression, difficulty in sleeping, headaches. In addition, while estrogen levels inherently decline with age, until menopause, some circumstances may cause low estrogen in not yet perimenopausal women. 

Testosterone

It is one of the most significant androgens found in the body. The female body also releases testosterone and other androgens but in less amounts. This hormone accounts for fat distribution, muscle strength, bone mass, and red blood cell production in men and women.

Progesterone

The female reproductive system secretes this hormone. Progesterone, like estrogen, is an essential part of the menstrual cycle. It also aids in the preparation of the uterus for pregnancy and is an essential element in the early stages of pregnancy.

Inadequate progesterone levels can cause heavy and irregular menstrual cycles, as well as a variety of reproductive problems. Premature labour or miscarriage can result from a drop in estrogen levels during pregnancy. Furthermore, too much progesterone may raise the risk of breast cancer.

Insulin

It is prepared by the pancreas. It has numerous roles, but its primary role is converting glucose into glycogen and regulating blood sugar levels.

Cortisol

Cortisol is a steroid hormone created by the adrenal glands. It has many duties that aid in keeping us healthy. For example, cortisol regulates metabolism, it acts as an anti-inflammatory agent, leveling blood pressure.

It is sometimes called a stress hormone because the higher level of cortisol is released under stress. A high level of cortisol can cause hypertension, sleep loss, anxiety, and autoimmune issues, a low level of cortisol can lead to low blood pressure, weakness, fatigue, etc.

Growth Hormone

Human growth hormone is abbreviated as HGH and is formed by the pituitary gland. HGH’s primary responsibility is growth and development. It promotes cell growth, cell regeneration, and cell reproduction in children. It increases metabolism.

Adrenaline

Adrenaline is a stress hormone. Adrenaline’s primary responsibility is to prepare the body for its “fight or flight” situation and allow for quick decision-making in dangerous or stressful circumstances. Excess concentration of adrenaline may lead to high blood pressure, rapid heartbeat, etc.

Thyroid Hormones

Thyroid hormones are created in the thyroid gland. They serve a variety of crucial tasks in the body. The thyroid hormone’s most significant responsibility is handling metabolism. An imbalance of thyroid hormones can cause severe conditions like Grave’s disease or Hashimoto’s disease, which can cause difficulties with weight control and energy levels.

Conclusion

Transmission of these hormones from neighboring cells to tissues in different regions of the body is done by releasing these hormones in the blood. Blood transmits these hormones to the target cells. Hormones are released in the blood that carries these chemicals to the required target. Hormones produce reactions in the targeted cells, which have a receptor for a signal. The tissues, cells, and organs that secrete hormones constitute the endocrine system.