Steroids display varied biological functions and play a crucial role in the
fascinating fields of biology, chemistry, and medicine.Steroids encompass wideranging natural products which are abundantly encountered in eukaryotic organisms.
These exhibit a pivotal role in regulating the cellular functions of animals, plants, and
fungi. Furthermore, they act as chemical messengers in the human body and get
secreted in the systemic circulation and extracellular fluids, where they regulate
metabolic, immune, and reproductive functions. Steroids are the fundamental
components of cell membranes and serve primarily as signalling molecules. This
chapter gives a comprehensive overview of physiologically active steroids in various
organisms.The biological activities of various steroid classes have been discussed in
detail. Glucocorticoids are a class of steroid hormones that regulate the metabolic
processes involving the formation of glucose from amino acids and fatty acid
deposition of glycogen in the liver. Another important group of hormones, called
mineralocorticoids, helps in balancing water and electrolyte content in the body and
primarily affects the kidney. The principal class of steroids viz. the sex hormones are
essentially crucial for the development and maintenance of reproductive function and
cause stimulation of secondary sexual characteristics in humans. To summarize,
steroids stabilize and regulate the structure and functions of cellular membranes and
play a crucial role in regulating growth and development.
Keywords: Steroids, Natural products, Hormones, Sterols, Therapeutic steroids.
