Specialty Corner: The Effects of Testosterone Therapy in Females on Lipid Parameters and Cardiovascular Disease Risk

Testosterone is a predominantly male hormone responsible for virilization of the external male genitalia during embryonic development, promotion of somatic growth, and secondary sexual characteristics in puberty, normal sexual function and libido in both males and females, and promotion of bone formation, bone health and maintenance of bone and muscle mass in adults.(1,2) It circulates in females at approximately  13-14% of the level observed in males.(3) Testosterone levels in females decrease from approximately 20 years to 40 years of age(4) and start rising again between 38 and 50 years old, but never reach the level of 20-year old.(4,5)

Testosterone (replacement) therapy is increasingly used in women for the treatment of sexual dysfunction.(6) It is the principal gender-affirming hormone therapy (GHT) used in transgender males (TGMs) to decrease gender dysphoria, suppress natal secondary sexual characteristics and induce changes (virilization) consistent with male gender and is continued lifelong to maintain virilization (7,8) See Table 1. Research has concluded that GHT generally leads to high satisfaction rates, increased quality of life and higher psychological well-being.(9,10,11) However, owing to increased association of hyperandrogenemia with cardiometabolic risk factors such as dyslipidemia, insulin resistance, hypertension, Type 2 diabetes, increased BMI, increase waist-to-hip ratio, in hyperandrogenic women with polycystic ovarian disease (PCOS), and to increase incidence of cardiometabolic disease in cisgender men compared to cisgender women, there is concern about cardiometabolic risk of androgen therapy.(12,13)

Most of the literature on transgender individuals adhering to GHT is based on retrospective cohort studies of short to medium (10 years) follow up duration, small sample size and relatively young age of cohorts followed. These factors may explain the inconclusiveness of the assessments of cardiometabolic disease biomarkers  in most of the available literature.(14) Prospective cohort studies, observational studies and cross-sectional studies in this population are inherently riddled with confounders, selection and reporting bias.  Most of these studies compared a cohort of transgender males (TGMs) with cisgender population or to the general population. Such comparison is potentially biased and confounded by lifestyle factors, and prone to associated pathology and other factors specific to the transsexual population aside from cross-sex hormone treatment. In this population, randomized placebo-controlled trials are difficult, and may be unethical, if not impossible.

Testosterone has both androgenic and anabolic properties and stimulates protein synthesis and fat oxidation thereby reducing lipid storage.(15,16) See table 2 for other effects of testosterone.  Treatment of TGMs (F-to-M) with intramuscular injections of 250 mg of testosterone ester every 2 to 3 weeks was shown to cause a decrease in subcutaneous fat, while simultaneously increasing visceral fat and BMI.(17,18) Zang et al noted a decrease in hormone sensitive lipase expression in the subcutaneous fat from postmenopausal women treated with oral testosterone undecanoate, which may explain the shift of fat accumulation to the abdominal viscera. (19) They also noted an increase in the enzyme phosphodiesterase-3B involved in the antilipolytic action of insulin in adipocytes following oral administration of testosterone undecanoate.

In a systematic review and meta-analysis of 29 trials with moderate risk of bias, Maraka S. et al summarized the effect of sex hormone therapy on lipid levels and important cardiovascular outcome in the transgender population.(20) They noted a statistically significant increase in triglyceride levels at 3 to 6 months of therapy (9 mg/dL; 95% CI: 2.5 to 15.5 mg/dL) and at >24 months (21.4 mg/ dL; 95% CI:0.1 to 42.6 mg/dL) compared to baseline. There was a statistically significant decrease in serum high density lipoprotein-cholesterol (HDL-C) levels across all follow up periods, with highest change at >24 months (-8.5 mg/dL; 95% CI: -13.0 to -3.9 mg/dL). The serum low density lipoprotein-cholesterol (LDL-C) when measured at 12 months showed a statistical increase (11.3 mg/dL; 95% CI: 
55 TO 17.1 mg/dL) and at >24 months (17.8 mg/dL; 95% CI: 3.5 to 32.1 mg/dL). Total cholesterol (TC) change was not statistically significant at any time during the period. Goh H.H. et al observed that supraphysiologic levels of testosterone in women caused statistical increase in TC, TG, LDL-C, apolipoprotein B (APO B) and atherogenic index LDL-C/HDL-C and statistically significant decrease in HDL-C and apolipoprotein A1 (APOA1)/APO B ratio (21); see Table 3. Their findings were corroborated in a study with synthetic androgens.(22)

Reports of various effects of GHT on blood pressure have been inconsistent and varied from elevated systolic (SBP) and diastolic (DBP) pressures (23), increase in SBP, but no change in DBP (24,25); no change in SBP and DBP (26); no change in SBP but significant change  in DBP.(27) Yiu-Fai C. et al noted that while oophorectomy in spontaneously hypertensive rats was associated with decreased renal renin, renal and hepatic angiotensinogen mRNA, but it did not affect blood pressure and plasma renin. However, administration of testosterone caused increase in blood pressure, plasma renin, renal renin and angiotensinogen mRNA, and hepatic angiotensinogen mRNA levels, suggesting an androgen-dependent development of hypertension in spontaneously hypertensive rats may be related to 
androgen-induced activation of the reninangiotensin system.(28)

High levels of testosterone are associated with increased level of the potent vasoconstrictor, endothelin, in postmenopausal women (29) and in TGM. (30) Androgen administration reduces insulin sensitivity in young, regularly menstruating females (31) and peripheral glucose uptake in TGMs (32), while antiandrogen therapy improves insulin sensitivity in hyperandrogenic females. (33,34) Testosterone therapy in TGMs have been reported to result in increased hepatic lipase activity.(17)

TGMs treated with GHT compared with age-matched untreated TGMs had higher brachial-ankle pulse wave velocity, no difference in carotid augmentation index (23), higher brachial artery diameter and reduced nitrate-induced vascular response, and similar endothelial function.(35) Longterm high dose treatment with androgen is likely to cause decreased flow mediated and decreased endothelial function in TGM (36), and increased arterial stiffness.(37)

Naessen et al observed that independent of traditional risk factors, women with total testosterol in the lowest quintile had the greatest risk of CVD and allcause mortality over a period of 4.5 year follow-up.(38) Some trials showed that postmenopausal women with low testosterone have an impaired endothelial function (39), an increased risk of CVD independent of metabolic factors (40,41), increased carotid atherosclerosis.(42) Several studies including a case-controlled study of 364 postmenopausal women from Atherosclerosis Risk in Communities Study (ARIC) (43,44,45,46,47) and a study of approximately 2000 postmenopausal women in the Multi-Ethnic Study of Atherosclerosis (MESA) (46) noted increased CIMT in women with low testosterone. In contrast, MESA women (46) with higher testosterone levels had extensive coronary artery calcium score and 528 postmenopausal women with high testosterone in the Rotterdam study (48) had increased aortic atherosclerosis. Certain other trials showed significantly lower intimal-medial thickness wall in the highest testosterone tertile compared with those in the lower testosterone tertile. (42) These suggest a possible U-shaped relationship between testosterone and cardiovascular disease.(49) 
Some experimental studies have shown that androgens inhibit apoptosis, suppress proinflammatory cytokine activity, and enhance smooth muscle cell proliferation - factors that are unfavorable to atheroma formation, that lead to maintenance of plaque integrity.(50) Malkin CJ et al suggested that these may be the mechanism by which androgen deficiency impacts coronary artery disease in men, and that this may be true for women with low testosterone.(50) See Table 2.

Two historical case-controlled studies published in communications in the New England Journal of medicine in 1939 and in the Journal of Clinical Endocrinology and Metabolism in 1946 by Maurice Lesser MD on a total of 122 men and 12 women ages from 34 years to 77 years with established clinical diagnosis of angina showed sustained improvement of anginal pains that began from average of 28 days following initiation of several injections of testosterone propionate every second and fifth day through 2-34 months after the last injection.(51,52) Similar favorable effects of testosterone propionate on angina pectoris was confirmed by other investigators.(53,54,55,56)

Despite increased association of cardiometabolic risk profile in TGMs on testosterone therapy, existing epidemiological data lack any consistent evidence of increased risk of MI and stroke. A retrospective observational study by Kesteren et al that looked at 293 TGMs receiving GHT for a total 2418 patientyears did not find any significant difference in the standardized incidence ratio (SIR) in myocardial infarction (MI) between TGMs and CGFs.(57) In a cohort of 365 TGMs at a University gender clinic in Netherlands with a mean age of 26.1 years (range 16-57 years, only 6 over 65 years of age), followed up for 18.5 years for 6866 patient-years of follow up, the use of testosterone in doses used for hypogonadal men seemed safe.(58) Only one MI was observed in a 72 y/o TGM subject after 42 years of testosterone treatment. In summary, despite existence of unfavorable cardiometabolic risk profile including blood pressure, atherogenic lipid and lipoprotein profile, there is no consistent or convincing evidence of increased risk of CAD or stroke associated with testosterone therapy. Testosterone has both vasoprotective and vasoinjurious properties (see Table 2) and TGMs do not have more CV events in observational, cross sectional and prospective or retrospective cohort studies. It is possible that physiologic levels of testosterone are beneficial for optimal cardiovascular health in women and that suboptimal or supraphysiologic levels are detrimental to cardiovascular health, and that doses used in hypogonadal men are safe. More longterm studies that are adequately-powered and well-controlled to address all possible confounders may be needed to come to a better understanding of the effect of longterm testosterone use on cardiovascular health in females.

Disclosure statement: Dr. Nwizu has no financial disclosures to report.

References 

1. Handelsman DJ (January 2013). “Androgen Physiology, Pharmacology and Abuse”. Endotext [Internet]. WWW.ENDOTEXT. ORG. MDText.com, Inc.
2. Androgen replacement therapy in women Cameron, Deborah R et al. Fertility and Sterility, Volume 82, Issue 2, 273 - 289
3. doi:10.1373/clinchem.2003.027565. PMID 14981046.
4. Zumoff B, Strain GW, Miller LK, Rosner W. Twenty-four hour mean plasma testosterone concentration declines with age in normal premenopausal women. J Clin Endocrinol Metab 1995;80:1429– 1430
5. Sowers MF, Zheng H, McConnell D, Nan B, Karvonen-Gutierrez CA, Randolph Jr JF. Testosterone, sex hormone binding globulin and free androgen index among adult women: chronological and ovarian aging. Hum Reprod 2009; 24: 2276–2285.
6. David S.R, Moreau M, Kroll R, Bouchard Celine, Panay N, Gass M, Braunstein G, Hirschberg A.L, Rodenberg C, Pack S, Koch H, Moufarege A, et al., for the APHRODITE Study Team.  Testosterone for Low Libido in Postmenopausal Women Not Taking Estrogen. N Engl J Med 2008; 359:2005-2017
7. Hembree WC, Cohen-Kettenis PT, Gooren L, Hannema SE, Meyer WJ, Murad MH, et al. Endocrine treatment of gender-dysphoric/ gender-incongruent persons: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab 2017;102:3869 –903. 8. Gooren LJ, Giltay EJ & Bunck MC. Long-term treatment of transsexuals with cross-sex hormones: extensive personal experience. Journal of Clinical Endocrinology and Metabolism 2008 93 19–25. (doi:10.1210/jc.2007-1809)
9. Kuiper B & Cohen-Kettenis P. Sex reassignment surgery: a study of 141 Dutch transsexuals. Archives of Sexual Behaviour 1988 17 439–457. (doi:10.1007/BF01542484) 10. Weyers S, Elaut E, De Sutter P, Gerris J, T’Sjoen G, Heylens G, De Cuypere G & Verstraelen H. Long-term assessment of the physical, mental, and sexual health among transsexual women. Journal of Sexual Medicine 2009 6 752–760. (doi:10.1111/j.1743-6109. 2008.01082.x)
11. Murad MH, Elamin MB, Garcia MZ, Mullan RJ, Murad A, Erwin PJ & Montori VM. Hormonal therapy and sex reassignment: a systemic review and meta-analysis of quality of life and psychosocial outcomes. Clinical Endocrinology 2010 72 214–231. (doi:10. 1111/j.1365-2265.2009.03625.x)
12. Schiffer L, Kempegowda P, Arlt W, O’Reilly MW. Mechanisms in endocrinology: the sexually dimorphic role of androgens in human metabolic disease. Eur J Endocrinol 2017;177:R125– 43.
13. Wierman ME, Basson R, Davis SR, Khosla S, Miller KK, Rosner W. Androgen therapy in women: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab 2006;91:3697–710.
14. Justine Defreyne, Laurens D L Van de Bruaene, Ernst Rietzschel, Judith Van Schuylenbergh, Guy G R T’Sjoen, Effects of GenderAffirming Hormones on Lipid, Metabolic, and Cardiac Surrogate Blood Markers in Transgender Persons, Clinical Chemistry, Volume 65, Issue 1, 1 January 2019, Pages 119–134, https://doi. org/10.1373/clinchem.2018.288241
15. BS DJHMB. Androgen Physiology, Pharmacology and Abuse. [Updated 2016 Dec 12]. In: Feingold KR, Anawalt B, Boyce A, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText. com, Inc.; 2000-. Available from: https://www.ncbi.nlm.nih.gov/ books/NBK279000/
16. Shadid S. Fatty acid and glucose metabolism in upper body obesity: effects of diet and exercise compared to pioglitazone administration [Doctoral thesis]. Maastricht (the Netherlands): Universitaire Pers Maastricht, 2007:183pp.
17. Elbers JM, Giltay EJ, Teerlink T, Scheffer PG, Asscheman H, Seidell JC et al. Effects of sex steroids on components of the insulin resistance syndrome in transsexual subjects. Clin Endocrinol 2003; 58: 562–571.
18. Elbers JM, Asscheman H, Seidell JC, Megens JA, Gooren LJ . Longterm testosterone administration increases visceral fat in female to male transsexuals. J Clin Endocrinol Metab 1997; 82: 2044–2047.
19. Zang H, Ryden M, Wahlen K, Dahlman-Wright K, Arner P, Linden Hirschberg A . Effects of testosterone and estrogen treatment on lipolysis signaling pathways in subcutaneous adipose tissue of postmenopausal women. Fertil Steril 2007; 88: 100–106.
20. Maraka S, Singh Ospina N, Rodriguez-Gutierrez R, et al. Sex Steroids and Cardiovascular Outcomes in Transgender Individuals: A Systematic Review and Meta-Analysis. J Clin Endocrinol Metab. 2017;102(11):3914–3923. doi:10.1210/jc.2017-01643
21. Goh HH, Loke DF, Ratnam SS. The impact of long-term testosterone replacement therapy on lipid and lipoprotein profiles in women. Maturitas. 1995;21(1):65–70. doi:10.1016/03785122(94)00861-z
22. Bardin CW, Swerdloff RS, Santen RJ. Androgens: Risks and benefits. Special article. J Clin Endocrinol Metab 1991; 73: 4-7.
23. Emi Y, Adachi M, Sasaki A, Nakamura Y, Nakatsuka M. Increased arterial stiffness in female-to-male transsexuals treated with androgen. J Obstet Gynaecol Res. 2008; 34:890–897. doi: 10.1111/j.1447-0756.2008.00857.x
24. Colizzi M, Costa R, Scaramuzzi F, Palumbo C, Tyropani M, Pace V, Quagliarella L, Brescia F, Natilla LC, Loverro G, Todarello O. Concomitant psychiatric problems and hormonal treatment induced metabolic syndrome in gender dysphoria individuals: a 2 year follow-up study. J Psychosom Res. 2015; 78:399–406. doi: 10.1016/j.jpsychores.2015.02.001
25. Mueller A, Haeberle L, Zollver H, Claassen T, Kronawitter D, Oppelt PG, Cupisti S, Beckmann MW, Dittrich R. Effects of intramuscular testosterone undecanoate on body composition and bone mineral density in female-to-male transsexuals. J Sex Med. 2010; 7:3190–3198. doi: 10.1111/j.1743-6109.2010.01912.x
26. Elbers JM, Giltay EJ, Teerlink T, Scheffer PG, Asscheman H, Seidell JC, Gooren LJ. Effects of sex steroids on components of the insulin resistance syndrome in transsexual subjects. Clin Endocrinol (Oxf). 2003; 58:562–571. doi: 10.1046/j.1365-2265.2003.01753.x
27. van Velzen DM, Paldino A, Klaver M, Nota NM, Defreyne J, Hovingh GK, Thijs A, Simsek S, T’Sjoen G, den Heijer M. Cardiometabolic effects of testosterone in transmen and estrogen plus cyproterone acetate in transwomen. J Clin Endocrinol Metab. 2019; 104:1937–1947. doi: 10.1210/jc.2018-02138
28. Chen YF, Naftilan AJ, Oparil S. Androgen-dependent angiotensinogen and renin messenger RNA expression in hypertensive rats. Hypertension. 1992;19(5):456–463. doi:10.1161/01.hyp.19.5.456
29. Maturana MA, Breda V, Lhullier F, Spritzer PM . Relationship between endogenous testosterone and cardiovascular risk in early postmenopausal women. Metabolism 2008; 57: 961–965.
30. Polderman KH, Stehouwer CD, van Kamp GJ, Dekker GA, Verheugt FW, Gooren LJ. Influence of sex hormones on plasma endothelin levels. Ann Intern Med. 1993; 118:429–432. doi: 10.7326/00034819-118-6-199303150-00006
31. Diamond MP, Grainger D, Diamond MC, Sherwin RS, Defronzo RA. Effects of methyltestosterone on insulin secretion and sensitivity in women. J Clin Endocrinol Metab 1998; 83: 4420–4425.
32. Polderman KH, Gooren LJ, Asscheman H, Bakker A, Heine RJ . Induction of insulin resistance by androgens and estrogens. J Clin Endocrinol Metab 1994; 79: 265–271.
33. Ibanez L, Valls C, Ferrer A, Ong K, Dunger DB, De Zegher F . Additive effects of insulin-sensitizing and anti-androgen treatment in young, nonobese women with hyperinsulinism, hyperandrogenism, dyslipidemia, and anovulation. J Clin Endocrinol Metab 2002; 87: 2870–2874.
34. Moghetti P, Tosi F, Castello R, Magnani CM, Negri C, Brun E et al. The insulin resistance in women with hyperandrogenism is partially reversed by antiandrogen treatment: evidence that androgens impair insulin action in women. J Clin Endocrinol Metab 1996; 81: 952–960.
35. Credie RJMC, Bs C, Crohon JAMC, Turner LEO, Griffiths KA, Handelsman DJ, Celermajer DS. Vascular reactivity is impaired in genetic females taking high-dose androgens.J Am Coll Cardiol. 1998; 32:1331–1335
36. Gulanski BI, Flannery CA, Peter PR, Leone CA, Stachenfeld NS. Compromised endothelial function in transgender men taking testosterone. Clin Endocrinol (Oxf). 2020;92(2):138–144. doi:10.1111/cen.14132
37. Emi Y, Adachi M, Sasaki A, Nakamura Y, Nakatsuka M. Increased arterial stiffness in female-to-male transsexuals treated with androgen. J Obstet Gynaecol Res. 2008;34(5):890–897. doi:10.1111/j.1447-0756.2008.00857.x
38. Naessen T, Sjogren U, Bergquist J, Larsson M, Lind L, Kushnir MM. Endogenous steroids measured by high-specificity liquid chromatography-tandem mass spectrometry and prevalent cardiovascular disease in 70-year-old men and women. J Clin Endocrinol Metab. 2010;95:1889–1897.
39. Montalcini T, Gorgone G, Gazzaruso C, Sesti G, Perticone F, Pujia A . Endogenous testosterone and endothelial function in postmenopausal women. Coron Artery Dis 2007; 18: 9–13.
40. KaczmarekA Reczuch K Majda J Banasiak W & Ponikowski P. The association of lower testosterone level with coronary artery disease in postmenopausal women. International Journal of Cardiology 20038753–57.
41. RakoS. Testosterone deficiency: a key factor in the increased cardiovascular risk to women following hysterectomy or with natural aging? Journal of Women’s Health 19987825–829.
42. BerniniGP Moretti A Sgro’ M Argenio GF Barlascini CO Cristofani R & Salvetti A. Influence of endogenous androgens on carotid wall in postmenopausal women. Menopause 2001843–50
43. Bernini GP, Sgro’ M, Moretti A, Argenio GF, Barlascini CO, Cristofani R, Salvetti A 1999 Endogenous androgens and carotid intimal-medial thickness in women. J Clin Endocrinol Metab 84:2008–2012. 
44. Golden SH, Maguire A, Ding J, Crouse JR, Cauley JA, Zacur H, Szklo M 2002 Endogenous postmenopausal hormones and carotid atherosclerosis: a case-control study of the atherosclerosis risk in communities cohort. Am J Epidemiol 155:437–445.
45. Montalcini T, Gorgone G, Gazzaruso C, Sesti G, Perticone F, Pujia A 2007 Role of endogenous androgens on carotid atherosclerosis in non-obese postmenopausal women. Nutr Metab Cardiovasc Dis 17:705–711.
46. Ouyang P, Vaidya D, Dobs A, Golden SH, Szklo M, Heckbert SR, Kopp P, Gapstur SM 2009 Sex hormone levels and subclinical atherosclerosis in postmenopausal women: the Multi-Ethnic Study of Atherosclerosis. Atherosclerosis 204:255–261.
47. Debing E, Peeters E, Duquet W, Poppe K, Velkeniers B, Van den Brande P 2007 Endogenous sex hormone levels in postmenopausal women undergoing carotid artery endarterectomy. Eur J Endocrinol 156:687–693.
48. Hak AE, Witteman JC, de Jong FH, Geerlings MI, Hofman A, Pols HA 2002 Low levels of endogenous androgens increase the risk of atherosclerosis in elderly men: the Rotterdam study. J Clin Endocrinol Metab 87:3632–3639.
49. Yeap BB. Testosterone and its metabolites: differential associations with cardiovascular and cerebrovascular events in men. Asian J Androl. 2018;20:109–14.
50. Malkin CJ, Pugh PJ, Jones RD, Jones TH, Channer KS 2003 Testosterone as a protective factor against atherosclerosis— immunomodulation and influence upon plaque development and stability. J Endocrinol 178:373–380.]
51. LESSER, M. A. The treatment of angina pectoris with testosterone propionate; preliminary report. New England J. Mcd. 226: 51-54, (1942).
52. LESSER MA. Testosterone propionate therapy in one hundred cases of angina pectoris. J Clin Endocrinol Metab. 1946;6:549–557. doi:10.1210/jcem-6-8-549
53. WALKER, T. C. The use of testosterone propionate and estrogenic substance in treatment of essential hypertension, angina pectoris and peripheral vascular disease. J. Clin. Endocrinol. 2: 560-568 (1942).
54. SIGLER, L. H. AND J. TULGAN. Treatment of angina pectoris by testosterone. New York State J. Med. 43: 1424-1428 (1943).
55. STRONG, G. F. AND A. W. WALLACE. Treatment of angina pectoris and peripheral vascular disease with sex hormones. Canad. M. A. J. 50: 30-33 (1944).
56. AVALDMAN, S. The treatment of angina pectoris with testosterone propionate. J. Clin. Endocrinol. 5: 305-317 (1945).
57. 12.van Kesteren PJ, Asscheman H, Megens JA, Gooren LJ. Mortality and morbidity in transsexual subjects treated with crosssex hormones. Clin Endocrinol (Oxf). 1997; 47:337–342. doi: 10.1046/j.1365-2265.1997.2601068.x
58. Asscheman, H., Giltay, E., Megens, J., de Ronde, W., van Trotsenburg, M., & Gooren, L. (2011). A long-term follow-up study of mortality in transsexuals receiving treatment with cross-sex hormones, European Journal of Endocrinology, 164(4), 635-642. Retrieved Feb 20, 2020, from https://eje.bioscientifica.com/view/ journals/eje/164/4/635.xml
59. Quinn VP, Nash R, Hunkeler E, Contreras R, Cromwell L, BecerraCulqui TA. Cohort profile: Study of Transition, Outcomes and Gender (STRONG) to assess health status of transgender people. BMJ Open 2017;7:e018121.
60. Dekker MJHJ, Wierckx K, Van Caenegem E, Klaver M, Kreukels BP, Elaut E. A European network for the investigation of gender incongruence: endocrine part. J Sex Med 2016;13:994–9.
61. Wiik A, Andersson DP, Brismar TB, Chanpen S, Dhejne C, Ekström TJ. Metabolic and functional changes in transgender individuals following cross-sex hormone treatment: design and methods of the GEnder Dysphoria Treatment in Sweden (GETS) study. Contemp Clin Trials Commun 2018;10:148–53.
62. Lucas-Herald AK, Alves-Lopes R, Montezano AC, Ahmed SF, Touyz RM. Genomic and non-genomic effects of androgens in the cardiovascular
63. Deenadayalu VP, White RE, Stallone JN, Gao X, Garcia AJ. Testosterone relaxes coronary arteries by opening the largeconductance, calcium-activated potassium channel. Am J Physiol Heart Circ Physiol. 2001;281:H1720–H1727. doi: 10.1152/ ajpheart.2001.281.4.H1720
64. Jones RD, English KM, Jones TH, Channer KS. Testosteroneinduced coronary vasodilatation occurs via a non-genomic mechanism: evidence of a direct calcium antagonism action. Clin Sci (Lond). 2004;107:149– 158. doi: 10.1042/CS20030386
65. Tambo A, Roshan MH, Pace NP. Testosterone and cardiovascular disease. Open Cardiovasc Med J. 2016;10:1–10. doi: 10.2174/ 1874192401610010001
66. Wu SZ, Weng XZ. Therapeutic effects of an androgenic preparation on myocardial ischemia and cardiac function in 62 elderly male coronary heart disease patients. Chin Med J (Engl) 1993; 106: 
415–8
67. Kelly DM, Jones TH. Testosterone: a vascular hormone in health and disease. J Endocrinol 2013; 217: R47–71.
68. Pugh PJ, Jones TH, Channer KS. Acute haemodynamic effects of testosterone in men with chronic heart failure. Eur Heart J 2003; 24: 909–15.
69. Malkin CJ, Morris PD, Pugh PJ, English KM, Channer KS. Effect of testosterone therapy on QT dispersion in men with heart failure. Am J Cardiol 2003; 92: 1241–3
70. Schwartz JB, Volterrani M, Caminiti G, Marazzi G, Fini M, et al. Effects of testosterone on the Q-T interval in older men and older women with chronic heart failure. Int J Androl 2011; 34: e415–21
71. Scragg JL, Dallas ML, Peers C. Molecular requirements for L-type Ca2+ channel blockade by testosterone. Cell Calcium 2007; 42: 11–5.
72. Jones RD, Pugh PJ, Jones TH, Channer KS. The vasodilatory action of testosterone: a potassium-channel opening or a calcium antagonistic action? Br J Pharmacol 2003; 138: 733–44
73. Lesser MA. Testosterone propionate therapy in one hundred cases of angina pectoris. J Clin Endocrinol Metab 1946; 6: 549–57.
74. Jaffe MD. Effect of testosterone cypionate on post exercise ST segment depression. Eur Heart J 1977; 39: 1217–22.
75. English KM, Steeds RP, Jones TH, Diver MJ, Channer KS. Low-dose transdermal testosterone therapy improves angina threshold in men with chronic stable angina: a randomized, double-blind, placebo-controlled study. Circulation 2000; 102: 1906–11.
76. Malkin CJ, Pugh PJ, Morris PD, Kerry KE, Jones RD, et al. Testosterone replacement in hypogonadal men with angina improves ischaemic threshold and quality of life. Heart 2004; 90: 871–6
77. Mathur A, Malkin C, Saeed B, Muthusamy R, Jones TH, et al. Long-term benefits of testosterone replacement therapy on angina threshold and atheroma in men. Eur J Endocrinol 2009; 161: 443–9.
78. Cornoldi A, Caminiti G, Marazzi G, Vitale C, Patrizi R, et al. Effects of chronic testosterone administration on myocardial ischemia, lipid metabolism and insulin resistance in elderly male diabetic patients with coronary artery disease. Int J Cardiol 2010; 142: 50–5
79. Webb CM, Adamson DL, de Zeigler D, Collins P. Effect of acute testosterone on myocardial ischemia in men with coronary artery disease. Am J Cardiol 1999; 83: 437–9.
80. Rosano GM, Leonardo F, Pagnotta P, Pelliccia F, Panina G, et al. Acute anti-ischemic effect of testosterone in men with coronary artery disease. Circulation 1999; 99: 1666–70
81. Thompson PD, Ahlberg AW, Moyna NM, Duncan B, Ferraro-Borgida M, et al. Effect of intravenous testosterone on myocardial ischemia in men with coronary artery disease. Am Heart J 2002; 143: 249–56
82. Webb CM, McNeill JG, Hayward CS, de Zeigler D, Collins P. Effects of testosterone on coronary vasomotor regulation in men with coronary heart disease. Circulation 1999; 100: 1690–6
83. Malkin CJ, Pugh PJ, Jones RD, Kapoor D, Channer KS, et al. The effect of testosterone replacement on endogenous inflammatory cytokines and lipid profiles in hypogonadal men. J Clin Endocrinol Metab 2004; 89: 3313–8
84. Newby AC & Zaltsman AB 1999 Fibrous cap formation or destruction - the critical importance of vascular smooth muscle cell proliferation, migration and matrix formation. Cardiovascular Research 41 345–360.
85. Williams MR, Ling S, Dawood T, Hashimura K, Dai A, Li H, Liu JP, Funder JW, Sudhir K & Komesaroff PA 2002 Dehydroepiandrosterone inhibits human vascular smooth muscle cell proliferation independent of ARs and ERs. Journal of Clinical Endocrinology and Metabolism 87 176–181.
86. Lopes RA, Neves KB, Pestana CR, et al. Testosterone induces apoptosis in vascular smooth muscle cells via extrinsic apoptotic pathway with mitochondria-generated reactive oxygen species involvement. Am J Physiol Heart Circ Physiol. 2014;306(11):H1485:H1494. doi:10.1152/ajpheart.00809.2013
87. Malkin, CJ., Pugh, PJ., Jones, RD., Jones, TH., & Channer, KS. (2003). Testosterone as a protective factor against atherosclerosis-immunomodulation and influence upon plaque development and stability, Journal of Endocrinology, 178(3), 373-380. Retrieved May 13, 2020, from https://joe.bioscientifica.com/view/journals/ joe/178/3/373.xml
88. Kanda N, Tsuchida T & Tamaki K 1996 Testosterone inhibits immunoglobulin production by human peripheral blood mononuclear cells. Clinical and Experimental Immunology 106 410–415
89. Li ZG, Danis VA & Brooks PM 1993 Effect of gonadal steroids on the production of IL-1 and IL-6 by blood mononuclear cells in vitro. Clinical and Experimental Rheumatology 11 157–162
90. Hatakeyama H, Nishizawa M, Nakagawa A, Nakano S, Kigoshi T & Uchida K 2002 Testosterone inhibits tumor necrosis factoralphainduced vascular cell adhesion molecule-1 expression in human aortic endothelial cells. FEBS 530 129–132
91. Schwartz JB, Volterrani M, Caminiti G, et al. Effects of testosterone on the Q-T interval in older men and older women with chronic heart failure. Int J Androl. 2011;34(5 Pt 2):e415-e421. doi:10.1111/j.1365-2605.2011.01163.x
92. Griggs RC, Kingston W, Jozefowicz RF, Herr BE, Forbes G, Halliday D. Effect of testosterone on muscle mass and muscle protein synthesis. J Appl Physiol (1985). 1989;66(1):498-503. doi:10.1152/ jappl.1989.66.1.498
93. Pugh PJ, Jones RD, West JN, Jones TH, Channer KS. Testosterone treatment for men with chronic heart failure. Heart 2004; 90: 446–7.
94. Malkin CJ, Pugh PJ, West JN, van Beek EJ, Jones TH, et al. Testosterone therapy in men with moderate severity heart failure: a double-blind randomized placebo controlled trial. Eur Heart J 2006; 27: 57–64.
95. Chignalia AZ, Oliveira MA, Debbas V, et al. Testosterone induces leucocyte migration by NADPH oxidase-driven ROS- and COX2dependent mechanisms. Clin Sci (Lond). 2015;129(1):39;48. doi:10.1042/CS20140548
96. Urhausen A, Albers T, Kindermann W. Are the cardiac effects of anabolic steroid abuse in strength athletes reversible. Heart 2004; 90: 496–501.