Skip Navigation
Skip to contents

Endocrinol Metab : Endocrinology and Metabolism


Author index

Page Path
Han Kyoung Choe  (Choe HK) 2 Articles
Diabetes, Obesity and Metabolism
Effects of Intermittent Fasting on the Circulating Levels and Circadian Rhythms of Hormones
Bo Hye Kim, Yena Joo, Min-Seon Kim, Han Kyoung Choe, Qingchun Tong, Obin Kwon
Endocrinol Metab. 2021;36(4):745-756.   Published online August 27, 2021
  • 10,717 View
  • 555 Download
  • 10 Citations
AbstractAbstract PDFPubReader   ePub   CrossRef-TDMCrossref - TDM
Intermittent fasting has become an increasingly popular strategy in losing weight and associated reduction in obesity-related medical complications. Overwhelming studies support metabolic improvements from intermittent fasting in blood glucose levels, cardiac and brain function, and other health benefits, in addition to weight loss. However, concerns have also been raised on side effects including muscle loss, ketosis, and electrolyte imbalance. Of particular concern, the effect of intermittent fasting on hormonal circadian rhythms has received little attention. Given the known importance of circadian hormonal changes to normal physiology, potential detrimental effects by dysregulation of hormonal changes deserve careful discussions. In this review, we describe the changes in circadian rhythms of hormones caused by intermittent fasting. We covered major hormones commonly pathophysiologically involved in clinical endocrinology, including insulin, thyroid hormones, and glucocorticoids. Given that intermittent fasting could alter both the level and frequency of hormone secretion, decisions on practicing intermittent fasting should take more considerations on potential detrimental consequences versus beneficial effects pertaining to individual health conditions.


Citations to this article as recorded by  
  • Fasting intervention and its clinical effects on the human host and microbiome
    Sofia K. Forslund
    Journal of Internal Medicine.2023; 293(2): 166.     CrossRef
  • Thermodynamic Assessment of the Effects of Intermittent Fasting and Fatty Liver Disease Diets on Longevity
    Melek Ece Öngel, Cennet Yildiz, Özge Başer, Bayram Yilmaz, Mustafa Özilgen
    Entropy.2023; 25(2): 227.     CrossRef
  • Effects of Intermittent Fasting on Hypothalamus–Pituitary–Thyroid Axis, Palatable Food Intake, and Body Weight in Stressed Rats
    Cinthia García-Luna, Ixchel Prieto, Paulina Soberanes-Chávez, Elena Alvarez-Salas, Iván Torre-Villalvazo, Gilberto Matamoros-Trejo, Patricia de Gortari
    Nutrients.2023; 15(5): 1164.     CrossRef
  • Intermittent fasting, high-intensity interval training, or a combination of both have beneficial effects in obese mice with nonalcoholic fatty liver disease
    Patrícia de Castro-de-Paiva, Thatiany de Souza Marinho, Carlos Alberto Mandarim-de-Lacerda, Marcia Barbosa Aguila
    The Journal of Nutritional Biochemistry.2022; 104: 108997.     CrossRef
  • Optimal Timing of Thyroid Hormone Replacement During Ramadan Fasting: A Randomized Controlled Trial in Patients with Prior Total Thyroidectomy
    Khalid M. Al-Qahtani, Ibraheem Ahmed Aldeeri, Amal M. Alshaibi, Norah Salman Alshabib, Rakan M. Barghouthi, Ebtihal Y. Alyusuf, Anwar Ali Jammah
    Thyroid.2022; 32(9): 1029.     CrossRef
  • Exploring the Effects of Energy Constraints on Performance, Body Composition, Endocrinological/Hematological Biomarkers, and Immune System among Athletes: An Overview of the Fasting State
    Hadi Nobari, Saber Saedmocheshi, Eugenia Murawska-Ciałowicz, Filipe Manuel Clemente, Katsuhiko Suzuki, Ana Filipa Silva
    Nutrients.2022; 14(15): 3197.     CrossRef
  • Alternate day fasting and time-restricted feeding may confer similar neuroprotective effects during aging in male rats
    Sukanya Bhoumik, Rashmi Kesherwani, Raushan Kumar, Syed Ibrahim Rizvi
    Biogerontology.2022; 23(6): 757.     CrossRef
  • Intermittent Fasting—A Healthy Dietary Pattern for Diabetic Nephropathy
    Ming Yang, Wei Chen, Liyu He, Di Liu, Li Zhao, Xi Wang
    Nutrients.2022; 14(19): 3995.     CrossRef
  • Umbrella review of time-restricted eating on weight loss, fasting blood glucose, and lipid profile
    Han Shi Jocelyn Chew, Wei How Darryl Ang, Zhen Yang Abel Tan, Wen Wei Ang, Kin Sun Chan, Ying Lau
    Nutrition Reviews.2022;[Epub]     CrossRef
  • β-hydroxybutyrate as an Anti-Aging Metabolite
    Lian Wang, Peijie Chen, Weihua Xiao
    Nutrients.2021; 13(10): 3420.     CrossRef
Effect of Mefloquine, a Gap Junction Blocker, on Circadian Period2 Gene Oscillation in the Mouse Suprachiasmatic Nucleus Ex Vivo
Jinmi Koo, Han Kyoung Choe, Hee-Dae Kim, Sung Kook Chun, Gi Hoon Son, Kyungjin Kim
Endocrinol Metab. 2015;30(3):361-370.   Published online December 9, 2014
  • 2,664 View
  • 29 Download
  • 4 Citations
AbstractAbstract PDFPubReader   CrossRef-TDMCrossref - TDM

In mammals, the master circadian pacemaker is localized in an area of the ventral hypothalamus known as the suprachiasmatic nucleus (SCN). Previous studies have shown that pacemaker neurons in the SCN are highly coupled to one another, and this coupling is crucial for intrinsic self-sustainability of the SCN central clock, which is distinguished from peripheral oscillators. One plausible mechanism underlying the intercellular communication may involve direct electrical connections mediated by gap junctions.


We examined the effect of mefloquine, a neuronal gap junction blocker, on circadian Period 2 (Per2) gene oscillation in SCN slice cultures prepared from Per2::luciferase (PER2::LUC) knock-in mice using a real-time bioluminescence measurement system.


Administration of mefloquine causes instability in the pulse period and a slight reduction of amplitude in cyclic PER2::LUC expression. Blockade of gap junctions uncouples PER2::LUC-expressing cells, in terms of phase transition, which weakens synchrony among individual cellular rhythms.


These findings suggest that neuronal gap junctions play an important role in synchronizing the central pacemaker neurons and contribute to the distinct self-sustainability of the SCN master clock.


Citations to this article as recorded by  
  • High-Throughput Screening Assay for Detecting Drug-Induced Changes in Synchronized Neuronal Oscillations and Potential Seizure Risk Based on Ca2+ Fluorescence Measurements in Human Induced Pluripotent Stem Cell (hiPSC)-Derived Neuronal 2D and 3D Cultures
    Hua-Rong Lu, Manabu Seo, Mohamed Kreir, Tetsuya Tanaka, Rie Yamoto, Cristina Altrocchi, Karel van Ammel, Fetene Tekle, Ly Pham, Xiang Yao, Ard Teisman, David J. Gallacher
    Cells.2023; 12(6): 958.     CrossRef
  • The role of gap junctions in cell death and neuromodulation in the retina
    Gergely Szarka, Márton Balogh, ÁdámJ Tengölics, Alma Ganczer, Béla Völgyi, Tamás Kovács-Öller
    Neural Regeneration Research.2021; 16(10): 1911.     CrossRef
  • Programming effects of maternal stress on the circadian system of adult offspring
    Seongsik Yun, Eun Jeong Lee, Han Kyoung Choe, Gi Hoon Son, Kyungjin Kim, Sooyoung Chung
    Experimental & Molecular Medicine.2020; 52(3): 473.     CrossRef
  • Kisspeptin Neuron-Specific and Self-Sustained Calcium Oscillation in the Hypothalamic Arcuate Nucleus of Neonatal Mice: Regulatory Factors of its Synchronization
    Doyeon Kim, Sangwon Jang, Jeongah Kim, Inah Park, Kyojin Ku, Mijung Choi, Sukwon Lee, Won Do Heo, Gi Hoon Son, Han Kyoung Choe, Kyungjin Kim
    Neuroendocrinology.2020; 110(11-12): 1010.     CrossRef

Endocrinol Metab : Endocrinology and Metabolism