Corticosterone
[CAS# 50-22-6]

Identification

• Classification: API >> Antibiotics >> Other antibiotics
• Name: Corticosterone
• Synonyms: 11beta,21-Dihydroxyprogesterone; 17-Deoxycortisol; 4-Pregnene-11beta,21-diol-3,20-dione; Corticosteron; Kendall's compound B; NSC 9705; Reichstein's substance H
• Molecular Formula: C₂₁H₃₀O₄
• Molecular Weight: 346.46
• CAS Registry Number: 50-22-6
• EC Number: 200-019-6
• SMILES: C[C@]12CCC(=O)C=C1CC[C@@H]3[C@@H]2[C@H](C[C@]4([C@H]3CC[C@@H]4C(=O)CO)C)O

Properties

• Density: 1.21±0.1 g/cm³ (20 ºC 760 Torr), Calc.^*
• Melting point: 185.3 ºC^**

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software V11.02 (©1994-2014 ACD/Labs)

^** Wassvik, Carola M.; Journal of Medicinal Chemistry 2008, V51(10), P3035-3039.

Safety Data

• Hazard Symbols: GHS07 Warning
• Hazard Statements: H317
• Precautionary Statements: P261-P272-P280-P302+P352-P321-P333+P317-P362+P364-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin sensitization	Skin Sens.	1	H317

Discovory and Applicatios

Corticosterone is a naturally occurring steroid hormone classified as a glucocorticoid. It plays a crucial role in the regulation of energy, immune responses, and stress reactions in many vertebrate species. Structurally, corticosterone is a 21-carbon steroid derived from cholesterol and is biosynthesized in the adrenal cortex, specifically in the zona fasciculata. It is one of the key end products of the hypothalamic-pituitary-adrenal (HPA) axis, a major neuroendocrine system that controls reactions to stress and regulates various body processes including digestion, the immune system, mood, and energy storage and expenditure.

The discovery of corticosterone dates back to early studies on adrenal function in the 1930s and 1940s. Scientists investigating the physiological effects of adrenal gland extracts eventually isolated various corticosteroids, including corticosterone, and identified their distinct biological activities. Corticosterone was recognized as one of the principal glucocorticoids in many non-human vertebrates, especially rodents, reptiles, and birds. In humans and other primates, however, cortisol is the predominant glucocorticoid, with corticosterone playing a more minor role.

In terms of biosynthesis, corticosterone is produced from progesterone through a sequence of enzymatic reactions involving 21-hydroxylation and 11β-hydroxylation. The intermediate compound, 11-deoxycorticosterone, is converted into corticosterone by the enzyme 11β-hydroxylase (CYP11B1). The regulation of corticosterone synthesis is controlled by adrenocorticotropic hormone (ACTH), which is released from the pituitary gland in response to corticotropin-releasing hormone (CRH) from the hypothalamus. This tightly regulated feedback loop ensures that corticosterone levels rise appropriately in response to physiological stress.

Functionally, corticosterone exerts its effects by binding to intracellular glucocorticoid receptors (GRs), which then translocate to the nucleus and influence gene expression. It helps mobilize energy reserves by promoting gluconeogenesis in the liver, increasing blood glucose levels, and modulating fat and protein metabolism. Additionally, corticosterone has potent anti-inflammatory and immunosuppressive properties, making it essential for controlling immune responses and inflammation during stress.

In laboratory research, corticosterone is frequently used as a biomarker for stress in animal studies. Its levels are measured in blood, saliva, or feces to assess the physiological stress response in experimental models, particularly in rodents. Such studies contribute to understanding the effects of stress on behavior, neurobiology, and disease processes. For example, chronic elevation of corticosterone in animal models is used to simulate conditions like depression, anxiety, and metabolic disorders.

Pharmacologically, corticosterone itself is not typically used as a therapeutic drug in clinical practice due to the availability of more potent and selective synthetic glucocorticoids such as dexamethasone, prednisone, and hydrocortisone. However, corticosterone plays a critical role in preclinical studies aimed at evaluating the effects of glucocorticoid signaling on various physiological and pathological processes.

In avian and reptilian physiology, corticosterone serves as the main glucocorticoid, analogous to cortisol in mammals. It regulates energy allocation during migration, reproduction, and immune defense. In birds, elevated corticosterone levels are often associated with environmental stressors such as predation risk, food scarcity, and habitat disturbance.

Additionally, corticosterone influences central nervous system activity, including mood, memory, and cognition. It affects neuronal excitability, neurogenesis, and synaptic plasticity. Research in neuroscience has shown that abnormal corticosterone levels, whether elevated or suppressed, can have profound effects on brain function and behavior, providing insights into the pathophysiology of mood and anxiety disorders.

Corticosterone continues to be an essential hormone for understanding the complex interplay between endocrine regulation and organismal response to environmental challenges. Its well-established role in stress physiology, energy homeostasis, and immune modulation makes it a key target for both basic and applied biomedical research.

References

1979. Serum levels of corticosterone and 18-hydroxy-11-deoxycorticosterone in the female rat at the high and low points of the circadian rhythm. Steroids, 33(2).
DOI: 10.1016/0039-128x(79)90025-4

1979. Plasma Concentrations of Progesterone and Corticosterone During the Ovulation Cycle of the Hen (Gallus Domesticus). Poultry Science, 58(1).
DOI: 10.3382/ps.0580211

1979. THE EFFECT OF INTRACEREBROVENTRICULAR ADMINISTRATION OF METHIONINE-ENKEPHALIN ON THE STRESS-INDUCED SECRETION OF CORTICOSTERONE IN MICE. British Journal of Pharmacology, 66(2).
DOI: 10.1111/j.1476-5381.1979.tb13660.x