Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Circadian Rhythms and Gene Regulation

Circadian Rhythms and Gene Regulation

The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent years,...

Circadian Rhythms and Gene Regulation

Circadian Rhythms and Gene Regulation

The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent years,...

The Pineal Gland

The Pineal Gland

The pineal gland, a diminutive endocrine structure named for its pinecone-shaped appearance, is situated atop the third ventricle within the diencephalon region of the forebrain. This gland, composed of secretory cells known as pinealocytes arranged in compact cords and clusters around dense particles of calcium salts, plays a pivotal role in hormonal regulation.
The primary secretion of the pineal gland is the hormone melatonin, derived from serotonin. The concentration of melatonin in the...

Understanding Sleep

Understanding Sleep

Sleep, an essential biological state, involves significant reductions in physical activity, sensory awareness, and interaction with the environment. This complex physiological process is primarily regulated by specific brain regions, notably the hypothalamus and pons, which govern the sleep-wake cycle or circadian rhythm.
The circadian rhythm, a nearly 24-hour cycle, is deeply influenced by environmental light cues. Light exposure directly affects the hypothalamus, which in turn regulates...

An Overview of the Endocrine System

An Overview of the Endocrine System

The endocrine system, a complex network of glands, orchestrates physiological balance within the body through the production and secretion of hormones. These hormones are chemical messengers in intercellular communication, acting as conduits between the secretory cells and distant target sites. They traverse the circulatory system by being released into the extracellular fluid, and their impact is specific to cells possessing receptors for a particular hormone.
The endocrine system collaborates...

Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response

Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response

Circadian rhythms are cyclic changes that are crucial in plasma drug concentrations. Various standard circadian parameters, including core body temperature, heart rate, and other cardiovascular factors, directly impact disease states and the therapeutic response to drug therapy.
The time of drug administration is an important factor to consider, as it can influence the toxic dose of a drug. For example, a study conducted by Prins et al. in 1997 examined the effects of the timing of...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Melatonin Impairs Glucose Tolerance, First-Phase Insulin Secretion, and Insulin Feedback Inhibition; Interaction With MTNR1B Diabetes Risk Variant.

Diabetes care·2026

Same author

Judicious elevation of ambient carbon dioxide during hypobaric hypoxia to improve oxygenation in airline passengers - a randomized feasibility study.

Journal of applied physiology (Bethesda, Md. : 1985)·2026

Same author

Constant-routine protocol reveals an endogenous circadian rhythm in diet-induced thermogenesis with a peak in the biological morning.

Metabolism: clinical and experimental·2026

Same author

Chronotype and disordered eating indicators: A systematic review and meta-analysis.

Clinical psychology review·2026

Same author

The efficacy of pink noise and earplugs for mitigating sleep disruption induced by different environmental noise sources.

Sleep health·2026

Same author

Peptides Targeting GDNF Family Receptor Alpha 1 (GFRα1) Mimic Glial Cell Line-Derived Neurotrophic Factor (GDNF) Bioactivity.

Journal of medicinal chemistry·2026

Search research articles

Related Experiment Video

Updated: May 29, 2026

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures

Published on: November 11, 2016

Circadian system, sleep and endocrinology.

Christopher J Morris¹, Daniel Aeschbach, Frank A J L Scheer

¹Division of Sleep Medicine, Brigham and Women's Hospital, Boston, MA, United States. cjmorris@rics.bwh.harvard.edu

Molecular and Cellular Endocrinology

|September 24, 2011

Summary

This summary is machine-generated.

Circadian timing systems regulate hormone levels, but misalignment disrupts this, negatively impacting metabolic health. Understanding these disruptions is key to developing countermeasures for conditions like shift work.

More Related Videos

Through-the-Wall Blood Sampling Method to Minimize Sleep Disruption in Clinical Settings

Through-the-Wall Blood Sampling Method to Minimize Sleep Disruption in Clinical Settings

Published on: June 13, 2025

Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments

Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments

Published on: August 8, 2019

Related Experiment Videos

Last Updated: May 29, 2026

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures

Published on: November 11, 2016

Through-the-Wall Blood Sampling Method to Minimize Sleep Disruption in Clinical Settings

Through-the-Wall Blood Sampling Method to Minimize Sleep Disruption in Clinical Settings

Published on: June 13, 2025

Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments

Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments

Published on: August 8, 2019

Area of Science:

Endocrinology
Chronobiology
Neuroscience

Background:

Hormone levels naturally fluctuate over 24 hours, influenced by sleep-wake cycles and the body's internal circadian timing system.
The suprachiasmatic nucleus (SCN) in the hypothalamus governs the circadian timing system, impacting hormone secretion through neural and humoral signals.
Peripheral tissues also possess circadian clock proteins involved in hormone regulation.

Purpose of the Study:

To explore the mechanisms by which the circadian timing system influences hormone secretion.
To investigate the consequences of circadian misalignment on hormonal and metabolic factors.
To highlight the need for further research into countermeasures for circadian disruption.

Main Methods:

Review of existing literature on circadian rhythms and hormone regulation.
Analysis of experimental data on the effects of circadian misalignment.
Discussion of the roles of the SCN and peripheral clocks in hormonal control.

Main Results:

Sleep significantly affects some hormones (e.g., growth hormone) but not others (e.g., melatonin), which are more strongly tied to circadian rhythms.
Circadian misalignment, common in shift workers, desynchronizes behavioral cycles from the internal clock.
Evidence suggests circadian misalignment adversely affects metabolic factors like glucose and insulin levels.

Conclusions:

The circadian timing system, involving the SCN and peripheral clocks, plays a crucial role in regulating hormone secretion.
Circadian misalignment can lead to detrimental metabolic and hormonal changes.
Further research is essential to elucidate the mechanisms behind these negative effects and develop effective countermeasures.