Proteins/Peptides Hormones

Main thing

Proteins/Peptides hormones are hormones made from amino acids; they send regulating messages to different parts of the body.

These hormones consist of chains of amino acids, with peptides being shorter and proteins longer. They are key players in the endocrine system, functioning as messengers that do not enter cells but bind to receptors on cell surfaces. They are synthesized in specific glands from amino acids, following the genetic instructions encoded in DNA. They start as larger molecules (preprohormones), are processed to prohormones, and finally become active hormones, ready to be released into the bloodstream when the body signals a need.

Examples of protein/peptide hormones and their producing glands include:

• Insulin (produced by the pancreas, regulates blood sugar)

• Glucagon (produced by the pancreas, increases blood sugar)

• Growth Hormone (produced by the pituitary gland, stimulates growth)

• Follicle-Stimulating Hormone (FSH) (produced by the pituitary gland, controls reproductive processes)

• Luteinizing Hormone (LH) (produced by the pituitary gland, also controls reproductive processes)

Terms

• Protein Hormone - A hormone made of long chains of amino acids. Example: Growth Hormone, produced by the pituitary gland, which helps the body grow.

• Peptide Hormone - A hormone made of short chains of amino acids. Example: Insulin, produced by the pancreas, which helps control blood sugar.

• Endocrine System - A system of glands that release hormones. Example: The pancreas, which releases insulin and glucagon.

• Water-Soluble - Able to dissolve in water. Example: Vitamin B, which dissolves in water and is not stored in the body.

• DNA - The material that carries genetic information. Example: Human DNA, which determines traits like height.

• Preprohormone - The initial form of a hormone, before it is processed. Example: Preproinsulin, produced by the pancreas, before it becomes insulin.

• Prohormone - A precursor to a hormone, needing further change to become active. Example: Proinsulin, which is turned into insulin.

An analogy

Peptide hormones are like letters shown to you by a postman at your door. The postman (hormone) doesn't leave the letter (doesn't enter the cell) but gives you the message (binds to a receptor), and then moves on.Example: Insulin instructing cells to absorb glucose from the blood.

A main misconception

Many people mistakenly believe that all hormones are steroids and can enter cells. However, protein and peptide hormones function by binding to cell surface receptors, not by entering the cells.Example: Insulin cannot enter cells; it binds to receptors on the cell surface to exert its effect.

The history

1. 1902 - Bayliss and Starling coined the term "hormone".

2. 1921 - Insulin was discovered, a major breakthrough in diabetes treatment.

3. 1953 - DNA's structure was determined, leading to understanding of genetic control over hormone production.

4. 1970s - The concept of peptide hormones expanded with the discovery of many new hormones.

5. 2000s - Advances in biotechnology improved hormone therapy, like growth hormone for deficiencies.

"Insulin is not a cure for diabetes; it is a treatment. It enables the diabetic to burn sufficient carbohydrates so that proteins and fats may be added to the diet in sufficient quantities to provide energy for the economic burdens of life." - Sir Frederick Banting, co-discoverer of insulin, Nobel Laureate.

Three cases how to use it right now

1. Diabetes Management: A person with diabetes uses insulin therapy, produced by the pancreas, to manage blood sugar levels.

2. Growth Hormone Deficiency in Children: A child with growth hormone deficiency receives injections of growth hormone, produced by the pituitary gland, to aid in normal growth.

3. Fertility Treatments: A woman undergoing fertility treatment may use LH and FSH, produced by the pituitary gland, to stimulate ovulation.

Interesting facts

• Insulin, a peptide hormone, can be produced synthetically and is used in diabetes treatment.

• Peptide hormones are produced on demand and not stored in large quantities.

• Insulin was the first hormone to be synthesized in the 1960s.

• Peptide hormones are water-soluble and cannot cross cell membranes.

• Treatments based on peptide hormones have revolutionized care for conditions like diabetes and growth deficiencies.