CYP1A2 genotype and acute effects of caffeine intake on growth hormone and testosterone response to resistance exercise

Rahimi, Mohammad Rahman; Faraji, Hassan; Khodamoradi, Maryam

doi:10.22059/sshr.2024.382033.1163

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	CYP1A2 genotype and acute effects of caffeine intake on growth hormone and testosterone response to resistance exercise
Sport Sciences and Health Research
دوره 16، شماره 2، مهر 2024، صفحه 279-293 اصل مقاله (506.13 K)
نوع مقاله: Research Paper
شناسه دیجیتال (DOI): 10.22059/sshr.2024.382033.1163
نویسندگان
Mohammad Rahman Rahimi^* ¹؛ Hassan Faraji²؛ Maryam Khodamoradi³
¹Department of Exercise Physiology, University of Kurdistan, Sanandaj 66177-15175, Iran. ORCID No: https://orcid.org/0000-0002-4302-1472
²Department of Physical Education and Sports Science, Marivan Branch, Islamic Azad University, Marivan, Iran.
³Department of Exercise Physiology, University of Kurdistan, 66177-15175 Sanandaj, Iran
چکیده
Background: Caffeine is widely recognized as a potent ergogenic aid commonly used to enhance exercise performance and recovery. However, individual responses to caffeine can vary significantly, a variability that might be explained by genetic differences. Aim: This study aimed to investigate the influence of the CYP1A2 rs762551 SNP on the effects of caffeine (CAF) consumption on growth hormone (GH) and testosterone (TS) levels response to resistance exercise (RE) in male athletes. Materials and Methods: Thirty resistance-trained men (mean age 21.72±4.06 years, weight 77.31±14.07 kg, height 179.31±5.08 cm) participated in a randomized, double-blind, placebo-controlled, crossover study. They consumed either CAF (6 mg/kg) or placebo (PL; 6 mg/kg maltodextrin) one hour before performing a RE protocol including three sets with 85% of 1RM and two-minute rest. CYP1A2 genotyping categorized participants as AA homozygous ("fast" metabolizers) or AC heterozygous ("slow" metabolizers). GH and TS levels were measured by ELISA methods. Results: Repeated measures ANOVA showed significant differences in GH levels across time (F=10.94, P=0.000), with significant time-group (F=4.3, P=0.019) and time-genotype-group interactions (F=3.83, P=0.024). One-way ANOVA indicated significant differences in GH levels between CAF and PL conditions in AA individuals, but not in AC/CC genotypes. For testosterone, significant effects of time (F=14.88, P=0.000) and time-group interaction (F=3.197, P=0.045) were observed. Post-RE CAF supplementation significantly increased serum GH and TS levels in AA individuals compared to PL. Both CAF and PL groups showed increased serum hormone concentrations post-exercise. Conclusion: In conclusion, the study demonstrated that caffeine consumption significantly increased serum levels of growth hormone and testosterone in individuals with the AA genotype of the CYP1A2 rs762551 SNP. These findings suggest that genetic variations play a role in the hormonal response to caffeine, which may have implications for exercise performance and recovery strategies.
کلیدواژه‌ها
Caffeine؛ CYP1A2 rs762551 SNP؛ hormonal response؛ resistance exercise

مراجع
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CYP1A2 genotype and acute effects of caffeine intake on growth hormone and testosterone response to resistance exercise

[1] McLellan TM, Caldwell JA, Lieberman HR. "A review of caffeine’s effects on cognitive, physical and occupational performance". Neuroscience & Biobehavioral Reviews. 2016; 71: 294-312. DOI: 10.1016/j.neubiorev.2016.09.001.

[2] Ebrahimi M, Telyari M. "The effect of caffeinated mouth rinsing on agility, jump height and service and spike accuracy in male volleyball players". Research in Exercise Nutrition. 2022; 1(3). DOI: 10.22034/REN.2023.139961.1021.

[3] Rahimi MR, Beaven CM. "Caffeine modifies the immune and anti-inflammatory responses to short incremental cycling exercise until exhaustion in humans: A pilot study". Journal of Science in Sport and Exercise. 2023: 6(4): 404-408. DOI: 10.1007/s42978-023-00226-z.

[5] Rahimi MR, Khabiri P, Faraji H. "Effects of caffeine ingestion on resistance exercise-induced apoptosis in athletes: A randomized, double-blind, placebo-controlled, crossover study". Progress in Nutrition. 2018; 20(4): 563-9. DOI: 10.23751/pn.v20i4.6442.

[6] Rahimi MR, Khodamoradi M, Falah F. "Effects of caffeine consumption before resistance exercise on blood levels of testosterone and growth hormones in male athletes". 2019; Koomesh. 2019; 21(4): 679-685.

[8] Rahimi MR, Semenova EA, Larin AK, Kulemin NA, Generozov EV, Łubkowska B, et al. "The ADORA2A TT genotype is associated with anti-inflammatory effects of caffeine in response to resistance exercise and habitual coffee intake". Nutrients. 2023; 15(7): 1634. DOI: 10.3390/nu15071634.

[9] Craig B, Brown R, Everhart J. "Effects of progressive resistance training on growth hormone and testosterone levels in young and elderly subjects". Mechanisms of Ageing and Development. 1989; 49(2): 159-69. DOI: 10.1016/0047-6374(89)90099-7.

[10] Burke LM. "Caffeine and sports performance". Applied Physiology, Nutrition, and Metabolism. 2008; 33(6): 1319-34. DOI: 10.1139/H08-130.

[11] Martins GL, Guilherme JPLF, Ferreira LHB, de Souza-Junior TP, Lancha Jr AH. "Caffeine and exercise performance: Possible directions for definitive findings". Frontiers in Sports and Active Living. 2020; 2: 574854. DOI: 10.3389/fspor.2020.574854.

[12] Graham T, Spriet L. "Metabolic, catecholamine, and exercise performance responses to various doses of caffeine". Journal of Applied Physiology. 1995; 78(3): 867-74.

[13] Graham TE. "Caffeine and exercise." Sports Medicine. 2001; 31(11): 785-807. DOI: 10.1186/1550-2783-7-5.

[14] Nawrot P, Jordan S, Eastwood J, Rotstein J, Hugenholtz A, Feeley M. "Effects of caffeine on human health". Food Additives & Contaminants. 2003; 20(1): 1-30. DOI: 10.1080/0265203021000007840.

[15] Lu S-S, Lau CP, Tung YF, Huang SW, Chen YH, Shih HC, et al. "Lactate and the effects of exercise on testosterone secretion: Evidence for the involvement of a cAMP-mediated mechanism". Medicine and Science in Sports and Exercise. 1997; 29(8): 1048-54. DOI: 10.1097/00005768-199708000-00010.

[17] Goldstein ER, Ziegenfuss T, Kalman D, Kreider R, Campbell B, Wilborn C, et al. "International society of sports nutrition position stand: caffeine and performance". Journal of the International Society of Sports Nutrition. 2010; 7(1): 5. DOI: https://doi.org/10.1186/1550-2783-7-5.

[18] Rahimi MR, Faraji H, Parhoon N. "The effect of MCT1 T1470A polymorphism on the number of repetition and the volume of resistance exercise in young male athletes". Journal of Applied Exercise Physiology. 2021; 17(34): 15-30. DOI: 10.22080/JAEP.2021.21794.2046.

[19] Grgic J, Trexler ET, Lazinica B, Pedisic Z. "Effects of caffeine intake on muscle strength and power: a systematic review and meta-analysis". Journal of the International Society of Sports Nutrition. 2018; 15(1): 11. DOI: 10.1186/s12970-018-0216-0.

[20] Pickering C, Grgic J. "Caffeine and exercise: what next?". Sports Medicine. 2019; 49: 1007-30. DOI: 10.1007/s40279-019-01101-0.

[21] Guest NS, Horne J, Vanderhout SM, El-Sohemy A. "Sport nutrigenomics: personalized nutrition for athletic performance". Frontiers in Nutrition. 2019; 6: 8. DOI: 10.3389/fnut.2020.606378.

[22] Rodak K, Kokot I, Kratz EM. "Caffeine as a factor influencing the functioning of the human body—Friend or foe?". Nutrients. 2021; 13(9): 3088. DOI: 10.3390/nu13093088.

[23] Cappelletti S, Daria P, Sani G, Aromatario M. "Caffeine: cognitive and physical performance enhancer or psychoactive drug?". Current Neuropharmacology. 2015; 13(1): 71-88. DOI: 10.2174/1570159X13666141210215655.

[24] Sachse C, Brockmöller J, Bauer S, Roots I. "Functional significance of a C→ A polymorphism in intron 1 of the cytochrome P450 CYP1A2 gene tested with caffeine". British Journal of Clinical Pharmacology. 1999; 47(4): 445-9. DOI: 10.1046/j.1365-2125.1999.00898.x.

[25] Pataky M, Womack C, Saunders M, Goffe J, D'lugos A, El‐Sohemy A, et al. "Caffeine and 3‐km cycling performance: Effects of mouth rinsing, genotype, and time of day". Scandinavian Journal of Medicine & Science in Sports. 2016; 26(6): 613-9. DOI: 10.1111/sms.12501.

[26] Womack CJ, Saunders MJ, Bechtel MK, Bolton DJ, Martin M, Luden ND, et al. "The influence of a CYP1A2 polymorphism on the ergogenic effects of caffeine". Journal of the International Society of Sports Nutrition. 2012; 9(1): 1. DOI: 10.1186/1550-2783-9-7.

[27] Rahimi R. "The effect of CYP1A2 genotype on the ergogenic properties of caffeine during resistance exercise: a randomized, double-blind, placebo-controlled, crossover study". Irish Journal of Medical Science. 2018: 1-9. DOI: 10.1007/s11845-018-1780-7.

[28] McGrath MC. The Significance of CYP1A2 Genotype on Caffeine Metabolism and exercise Performance. A Thesis Presented in Partial Fulfilment of the Requirements for the Degree of Master of Science in Human Nutrition, Massey University, Manawatu, New Zealand: Massey University; 2015.

[29] Grgic J, Pickering C, Bishop DJ, Schoenfeld BJ, Mikulic P, Pedisic Z. "CYP1A2 genotype and acute effects of caffeine on resistance exercise, jumping, and sprinting performance". Journal of the International Society of Sports Nutrition. 2020; 17(1): 21. DOI: 10.1186/s12970-020-00349-6.

[30] Grgic J, Pickering C, Del Coso J, Schoenfeld BJ, Mikulic P. "CYP1A2 genotype and acute ergogenic effects of caffeine intake on exercise performance: A systematic review". European Journal of Nutrition. 2021; 60: 1181-95. DOI: 10.1007/s00394-020-02427-6.

[32] Kraemer WJ, Ratamess NA, Hymer WC, Nindl BC, Fragala MS. "Growth hormone(s), testosterone, insulin-like growth factors, and cortisol: roles and integration for cellular development and growth with exercise". Frontiers in Endocrinology. 2020; 11: 33. DOI: 10.3389/fendo.2020.00033.

[33] Hochberg Z, Hertz P, Benderly A. "Caffein stimulates growth hormone secretion by cultured rat pituitary cells". Journal of Endocrinological Investigation. 1984; 7: 59-60. DOI: 10.1007/BF03348378.

[34] Beaven CM, Hopkins WG, Hansen KT, Wood MR, Cronin JB, Lowe TE. "Dose effect of caffeine on testosterone and cortisol responses to resistance exercise". International Journal of sport Nutrition and Exercise Metabolism. 2008; 18(2): 131-41. DOI: 10.1123/ijsnem.18.2.131.

[35] Wu BH, Lin JC. "Caffeine attenuates acute growth hormone response to a single bout of resistance exercise". Journal of Sports Science & Medicine. 2010; 9(2): 262. DOI: 10.1007/s40279-018-0997-y.

[36] Goto K, Ishii N, Takamatsu K. "Growth hormone response to training regimen with combined high-and low-intensity resistance exercises". International Journal of Sport and Health Science. 2004; 2: 111-8. DOI: 10.5432/ijshs.2.111.

[37] Ratamess NA, Hoffman JR, Ross R, Shanklin M, Faigenbaum AD, Kang J. "Effects of an amino acid/creatine energy supplement on the acute hormonal response to resistance exercise". International Journal of Sport Nutrition and Exercise Metabolism. 2007; 17(6): 608-23. DOI: 10.1123/ijsnem.17.6.608.

[38] Rahimi R. "The effect of CYP1A2 genotype on the ergogenic properties of caffeine during resistance exercise: A randomized, double-blind, placebo-controlled, crossover study". Irish Journal of Medical Science. 2019; 188(1): 337-45. DOI: 10.1007/s11845-018-1780-7.

[39] Shohet KL, Landrum RE. "Caffeine consumption questionnaire: a standardized measure for caffeine consumption in undergraduate students". Psychological Reports. 2001; 89(3): 521-6. DOI: 10.2466/pr0.2001.89.3.521.

[40] Boroujerdi SS, Rahimi R. "Acute GH and IGF-I responses to short vs. long rest period between sets during forced repetitions resistance training system". South African Journal for Research in Sport, Physical Education and Recreation. 2008; 30(2): 31-8. DOI: 10.4314/sajrs.v30i2.25980.

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