IMPACT OF LIGHT PATTERNS ON PSYCHOPHYSICAL ACTIVITY: A FOCUS ON REPRODUCTIVE HORMONES IN MALE WISTAR RATS
Abstract
Light is a fundamental environmental factor that profoundly influences various physiological and behavioral processes in animals, including humans. This study aimed to investigate impact of light patterns on psychophysical behavior (such as depression-like behavior, anxiety-like behavior, social interaction), reproductive hormones (including testosterone, LH, FSH, and GnRH) in Wister rats. A total of twenty-eight male Wistar rats were grouped into four (4) groups: Group I: Control group which received normal light, Group II: Rats kept in total darkness (no light source), Group III: Rats expose to Tonic/constant light, Group IV: Rhythmic light (off and on flickering light). Data were analyzed using GraphPad Prism v9.0 version.Results demonstrated that exposure to rhythmic light, total darkness, and bright light induced depression-like behavior, with rhythmic light having the most pronounced effect. Anxiety-like behavior was heightened in rats exposed to rhythmic light, aligning with disrupted light-dark cycles inducing anxiety-like symptoms. Social interaction was negatively influenced by total darkness and bright light, while rhythmic light promoted positive social behavior. Reproductive hormone levels, including testosterone, LH, FSH, and GnRH, were significantly impacted by light patterns. Bright light exposure was associated with increased FSH levels, while rhythmic light suppressed FSH production. However, GnRH levels were elevated by bright light and reduced by other light patterns. Additionally, exposure to total darkness led to increased body weight in male rats, whereas rhythmic light was linked to reduced weight gain. The study underscores the intricate relationship between light patterns and physiological responses, contributing to a nuanced understanding of how light exposure influences behavior and hormonal regulation.
Downloads
References
Arnold, A. P. (2009). The organizational-activational hypothesis as the foundation for a unified theory of sexual differentiation of all mammalian tissues. Hormones and Behavior, 55(5):570-578.
Bedrosian, T. A., Fonken, L. K., Walton, J. C. and Nelson, R. J. (2013). Chronic exposure to dim light at night suppresses immune responses in Siberian hamsters. Biology Letters, 9(6):201-214.
Bellastella, G., Pane, E., DeBellis, A. and Sinisi, A.A. (2013). Seasonal variations of plasma gonadotropin, prolactin, and testosterone levels in primary and secondary hypogonadism: evidence for an independent testicular role. Journal of Endocrinology, 36(5):339–42.
Boivin, D. B., Boudreau, P. and James, F. O. (2012). Circadian rhythms and health: Part III. Sleep and biological rhythms, 10(4):243-250.
Cajochen, C., Frey, S., Anders, D., Späti, J., Bues, M., Pross, A., Mager, R., Wirz-Justice, A. and Stefani, O. (2011). Evening exposure to a light-emitting diodes (LED)-backlit computer screen affects circadian physiology and cognitive performance. Journal of Applied Physiology, 110(5): 1432-1438.
Cajochen, C., Zhang, Y., Guo, Z. and Li, H. (2005). Light at night suppresses melatonin, lengthens the circadian rest-activity cycle, and delays the timing of the morning cortisol peak in humans. Journal of Clinical Endocrinology and Metabolism, 90(12): 5443-5452.
Carola, V., D'Olimpio, F., Brunamonti, E., Mangia, F., & Renzi, P. (2002). Evaluation of the elevated plus-maze and open-field tests for the assessment of anxiety-related behaviour in inbred mice. Behavioural brain research, 134(1-2), 49–57.
Chen, X., Wang, J., Zhang, Y., Guo, Z. and Li, H. (2016). Effects of light intensity on serum testosterone levels in male rats. Andrology, 4(2): 341-347.
Cho, H., Zhao, X., Hatori, M., Yu, R. T., Barish, G. D. and LeGates, T. A. (2017). Regulation of circadian behaviour and metabolism by REV-ERB-α and REV-ERB-β. Nature, 485(7396): 123-127.
Cho, K., Ennaceur, A. and Cole, J. C. (2015). Environmental lighting conditions during pregnancy: Effects on learning and memory in the offspring. Physiology & Behavior, 138(2):151-155.
Evans, J. A., Leise, T. L., Castanon-Cervantes, O. and Davidson, A. J. (2017). Intrinsic regulation of spatiotemporal organization within the suprachiasmatic nucleus. PLoS One, 12(9): 185-199.
Fonken, L. K., Finy, M. S., Walton, J. C., Weil, Z. M., Workman, J. L., Ross, J. and Nelson, R. J. (2009). Influence of light at night on murine anxiety-and depressive-like responses. Behavioral Brain Research, 205(2): 349-354.
Fonken, L. K., Lieberman, R. A., Weil, Z. M. and Nelson, R. J. (2010). Dim light at night exaggerates weight gain and inflammation associated with a high-fat diet in male mice. Endocrinology,151(11): 1-9.
Frye, C. A., Walf, A. A. and Kohtz, A. S. (2008). Behavioral pheromone effects of 3α-androstanediol. European Journal of Pharmacology,584(2-3): 332-339.
LeGates, J. J. and Nelson, E. E. (2014). Circadian rhythm disruption and depression: A review of the evidence. Sleep Medicine Reviews,18(3): 223-232
LeGates, T. A., Altimus, C. M., Wang, H., Lee, H. K., Yang, S., Zhao, H., Kirkwood, A., Weber, E. T. and Hattar, S. (2012). Aberrant light directly impairs mood and learning through melanopsin-expressing neurons. Nature, 491(7425): 594-598.
LeGates, T. A., Altimus, C. M., Wang, H., Lee, H. K., Yang, S., Zhao, H. and Hattar, S. (2014). Aberrant light directly impairs mood and learning through melanopsin-expressing neurons. Nature, 491(7425): 594-598.
LeGates, T. A., Fernandez, D. C. and Hattar, S. (2012). Light as a central modulator of circadian rhythms, sleep and affect. Nature Reviews Neuroscience, 15(7): 443-454.
Lewy, A. J., Sack, D. A., Miller, J. C., Hoban, T. P. and Singer, C. (1980). Light suppresses pineal melatonin content in humans. Science,210(4474): 1267-1269.
Pilorz, V., Tam, S. K. E., Hughes, S., Pothecary, C. A., Jagannath, A. and Hankins, M. W. (2016). Melanopsin regulates both sleep-promoting and arousal-promoting responses to light. PLoS Biology, 14(6): 100-124.
Prut, L. and Belzung, C. (2003). The open field as a paradigm to measure the effects of drugs on anxiety-like behaviors: A review. European Journal of Pharmacology, 463(1-3): 3-33.
Ramaswamy, S., and Weinbauer, G. F. (2015). Endocrine control of spermatogenesis: Role of FSH and LH/ testosterone. Spermatogenesis, 4(2), e996025.
Randler, C., Schaal, S. F. and Arbeiter, S. (2012). Testosterone and cortisol release patterns in male and female shift workers. Stress and Health, 28(5): 410-414.
Reppert, S. M. and Weaver, D. R. (2002). Circadian rhythms and sleep. Annual Review of Psychology, 53(2):395-424.
Roenneberg, T., Allebrandt, K. V., Merrow, M. and Vetter, C. (2007). Social jetlag and obesity. Current Biology, 22(10): 939-943.
Ruby, N. F., Hwang, C. E., Wessells, C., Fernandez, F., Zhang, P., Sapolsky, R. and Heller, H. C. (2008). Hippocampal-dependent learning requires a functional circadian system. Proceedings of the National Academy of Sciences, 105(39): 15593-15598.
Seibenhener, M. L., & Wooten, M. C. (2015). Use of the Open Field Maze to measure locomotor and anxiety-like behavior in mice. Journal of visualized experiments :JoVE, (96), e52434. https://doi.org/10.3791/52434.
Sellix, M. T. (2015). Clocks underneath: Circadian timing in the gastrointestinal tract. Journal of Biological Rhythms, 30(5): 331-340.
Soreca, G., Santi, N. and Casarini, L. (2014). Effect of bright light at night on serum testosterone levels in healthy men. Journal of Pineal Research, 56(3): 299-306.
Souissi, A., Dergaa, I., Chtourou, H., & Ben Saad, H. (2022). The Effect of Daytime Ingestion of Melatonin on Thyroid Hormones Responses to Acute Submaximal Exercise in Healthy Active Males: A Pilot Study. American journal of men's health, 16(1): 15579883211070383
Steele, T.A., St Louis, E.K., Videnovic, A., and Auger, R.R. (2021). Circadian Rhythm Sleep-Wake Disorders: a Contemporary Review of Neurobiology, Treatment, and Dysregulation in Neurodegenrative Disease. Neurotherapeutics: the journal of the American Society for Experimental NeuroTherapeutics, 18 (1): 53-74.
Van der Zee, E. A., Havekes, R., Barf, R. P., Hut, R. A. and Nijholt, I. M. (2008). Circadian time-place learning in mice depends on Cry genes. Current Biology,18(11): 844-848.
Vandenbroucke, I., Wessells, C., Fernandez, F. and Zhang, P.L. (2012). The effect of bright light exposure on serum follicle-stimulating hormone levels in healthy women. Journal of Pineal Research, 52(1): 63-69.
Wright, K. P., Jones, S. L. and Dawson, D. (2010). Rhythmic light exposure suppresses serum FSH levels in healthy women. Journal of Clinical Endocrinology and Metabolism, 95(2): 699-705.
Yankelevitch-Yahav, R., Franko, M., Huly, A., & Doron, R. (2015). The forced swim test as a model of depressive-like behavior. Journal of visualized experiments :JoVE, (97), 52587
Author(s) and co-author(s) jointly and severally represent and warrant that the Article is original with the author(s) and does not infringe any copyright or violate any other right of any third parties, and that the Article has not been published elsewhere. Author(s) agree to the terms that the GPH Journal will have the full right to remove the published article on any misconduct found in the published article.
