Low testosterone produce hypercoagulable state (Erem 2008)
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Hemostasis
Ajayi AA, Mathur R, Halushka PV. Testosterone increases human platelet thromboxane A2 receptor density and aggregation responses. Circulation. 1995 Jun 1;91(11):2742-7. BACKGROUND: The incidence of thrombotic cardiovascular disease is greater in men than in premenopausal women. Testosterone has been implicated as a significant risk factor for cardiovascular disease and for acute myocardial infarctions and strokes in young male athletes who abuse anabolic steroids. Thromboxane A2 (TXA2) is a vasoconstrictor and platelet proaggregatory agent that has been implicated in the pathogenesis of cardiovascular disease. We therefore tested the hypothesis that testosterone regulates the expression of human platelet TXA2 receptors. METHODS AND RESULTS: In a double-blind, placebo-controlled, randomized, parallel-group study, we determined the effects of testosterone cypionate 200 mg IM given twice, 2 weeks apart, or saline placebo in 16 healthy men. Platelet TXA2 receptor density (Bmax) and dissociation constant (Kd) were measured by use of the TXA2 mimetic 125I-BOP. Platelet aggregation responses to I-BOP and to thrombin and plasma testosterone concentrations were measured before treatment (pretreatment phase), at 2 and 4 weeks (active phase), and again at 8 weeks (recovery phase). Treatment with testosterone was associated with an increase in the Bmax value from 0.95 +/- 0.13 to 2.10 +/- 0.4 pmol/mg protein (n = 9), with a peak effect at 4 weeks (P = .001), returning to baseline by 8 weeks. There was no significant change in Bmax values in the saline-treated group. The Kd values were unchanged. Testosterone treatment was associated with a significant increase in the maximum platelet aggregation response to I-BOP (P < .001) at 4 weeks and returned to baseline at 8 weeks. The EC50 values were not significantly changed. Platelet TXA2 receptor density was positively correlated (r = .56, P < .001, n = 32 measurements) with pretreatment (endogenous) plasma testosterone levels (range, 215 to 883 ng/dL) but not Kd. CONCLUSIONS: Testosterone regulates the expression of platelet TXA2 receptors in humans. This may contribute to the thrombogenicity of androgenic steroids. PMID: 7758179 Ames PR, Tommasino C, Alves J, Morrow JD, Iannaccone L, Fossati G, Caruso S, Caccavo F, Brancaccio V. Antioxidant susceptibility of pathogenic pathways in subjects with antiphospholipid antibodies: a pilot study. Lupus. 2000;9(9):688-95. The pathogenesis of antiphospholipid antibody (aPL) related thrombosis is multifactorial and includes, amongst others, enhanced coagulation activation measured as prothrombin fragment 1 + 2 (F1 + 2), elevated plasma levels of von Willebrand factor (vWF), plasminogen activator inhibitor (PAI) and endothelin-1 (ET-1) as well as heightened thromboxane generation and lipid peroxidation. To evaluate the antioxidant susceptibility of some of the above pathways, probucol (500 mg/d orally, a cholesterol lowering agent bearing antioxidant properties) was administered for a three week period to 14 subjects with aPL and to seven healthy controls. At baseline aPL participants showed higher plasma levels of vWF (P = 0.006), ET-1 (P = 0.0002) and enhanced urinary excretion of 11-dehydro-thromboxane-B2 (TXB2) (P = 0.0004), F2-isoprostanes (marker of lipid peroxidation) (P = 0.02) and albumin (P = 0.04) than controls. In the aPL group baseline IgG anticardiolipin (aCL) titre positively related with urinary TXB2 (r2 = 0.43, P = 0.01) and inversely with urinary NOx (r2 = -0.6, P = 0.005) whereas urinary NOx and TXB2 were negatively correlated (r2 = -0.42, P = 0.01). After the treatment period significant decreases from baseline values were noted for PAI (P = 0.01), ET-1 (P = 0.006), TXB2 (P = 0.02), F2-isoprostanes (P = 0.01) and albuminuria (P = 0.01) in aPL participants but not in controls. These pilot data support oxidative sensitive mechanisms and a potential role for antioxidant treatment in the pathogenesis of aPL induced vasculopathy. Anderson RA, Ludlam CA, Wu FC. Haemostatic effects of supraphysiological levels of testosterone in normal men. Thromb Haemost. 1995 Aug;74(2):693-7. The effects of exogenous testosterone on the haemostatic system were studied in a group of 32 healthy men undergoing a clinical trial of hormonal male contraception. The men received 200 mg testosterone oenanthate (TE) weekly i.m., and plasma samples were taken pretreatment, at defined time points up to 52 weeks of treatment, and 4 and 8 weeks after discontinuing TE. This dose of TE caused a 2-fold increase in trough plasma testosterone levels. TE caused a fall in plasma fibrinogen concentration after 16 weeks of treatment. This was sustained for the duration of TE treatment and recovered to pretreatment levels during the recovery phase. There was also a sustained fall in the level of C4b binding protein which showed a rebound to levels above pretreatment during recovery. Levels of antithrombin III and prothrombin fragment F1.2 rose initially during TE treatment, and levels of protein C, protein S (free) and plasminogen activator inhibitor fell, but the concentrations of these factors all returned to pretreatment levels during continued treatment. There was no change in the plasma concentrations of beta-thromboglobulin, tissue plasminogen activator, protein S (total), or D-dimer. There was a sustained increase in haemoglobin concentration and haematocrit, without any change in platelet count. The observed changes were consistent with mild activation of the haemostatic system during initial treatment with testosterone. After several months the raised activation markers had returned to pretreatment levels indicating that a new equilibrium had been established which did not appear to be prothrombotic.(ABSTRACT TRUNCATED AT 250 WORDS) PMID: 8585008 Angelova P, Momchilova A, Petkova D, Staneva G, Pankov R, Kamenov Z. Testosterone replacement therapy improves erythrocyte membrane lipid composition in hypogonadal men. Aging Male. 2012 Sep;15(3):173-9. AIM: The aim of this study was to investigate the effects of testosterone replacement therapy (TRT) on erythrocyte membrane (EM) lipid composition and physico-chemical properties in hypogonadal men. METHODS: EM isolated from three patients before and after TRT with injectable testosterone undecanoate or testosterone gel were used for analysis of the phospholipid and fatty acid composition, cholesterol/phospholipid ratio, membrane fluidity, ceramide level and enzyme activities responsible for sphingomyelin metabolism. RESULTS: TRT induced increase of phosphatidylethanolamine (PE) in the EMs and sphingomyelin. Reduction of the relative content of the saturated palmitic and stearic fatty acids and a slight increase of different unsaturated fatty acids was observed in phosphatidylcholine (PC). TRT also induced decrease of the cholesterol/total phospholipids ratio and fluidization of the EM. DISCUSSION: The TRT induced increase of PE content and the reduction of saturation in the PC acyl chains induced alterations in the structure of EM could result in higher flexibility of the erythrocytes. The increase of the SM-metabolizing enzyme neutral sphingomyelinase, which regulates the content of ceramide in membranes has a possible impact on the SM signaling pathway. CONCLUSION: We presume that the observed effect of TRT on the composition and fluidity of the EM contributes for improvement of blood rheology and may diminish the thrombosis risk. Larger studies are needed to confirm the findings of this pilot study. PMID: 22776010 Bonithon-Kopp C, Scarabin PY, Bara L, Castanier M, Jacqueson A, Roger M. Relationship between sex hormones and haemostatic factors in healthy middle-aged men. Atherosclerosis. 1988 May;71(1):71-6. Associations of plasma testosterone and estradiol with some haemostatic factors (factor VII activity, fibrinogen, antithrombin III and alpha 2-antiplasmin) were cross-sectionally examined in 251 healthy, middle-aged men participating in the Paris Prospective Study II on risk factors for ischaemic heart disease. Testosterone levels were negatively correlated to factor VII activity and alpha 2-antiplasmin, the main inhibitor of fibrinolysis. No association was found either between testosterone levels and both fibrinogen and antithrombin III, or between estradiol levels and the set of haemostatic variables. The associations between testosterone and both factor VIIc and alpha 2-antiplasmin were independent of HDL-cholesterol, LDL-cholesterol, triglycerides, smoking, alcohol, body mass index and blood pressure. These results suggest that low circulating testosterone levels might be associated with a hypercoagulability state and therefore could contribute to an increased risk of IHD. PMID: 3377881 Campelo AE, Cutini PH, Massheimer VL. Testosterone modulates platelet aggregation and endothelial cell growth through nitric oxide pathway. J Endocrinol. 2012 Apr;213(1):77-87. The aim of the present study was to investigate the effect of testosterone on the modulation of cellular events associated with vascular homeostasis. In rat aortic strips, 5-20 min treatment with physiological concentrations of testosterone significantly increased nitric oxide (NO) production. The rapid action of the steroid was suppressed by the presence of an androgen receptor antagonist (flutamide). We obtained evidence that the enhancement in NO synthesis was dependent on the influx of calcium from extracellular medium, because in the presence of a calcium channel blocker (verapamil) the effect of testosterone was reduced. Using endothelial cell (EC) cultures, we demonstrated that androgen directly acts at the endothelial level. Chelerythrine or PD98059 compound completely suppressed the increase in NO production, suggesting that the mechanism of action of the steroid involves protein kinase C and mitogen-activated protein kinase pathways. It is known that endothelial NO released into the vascular lumen serves as an inhibitor of platelet activation and aggregation. We showed that testosterone inhibited platelet aggregation and this effect was dependent on endothelial NO synthesis. Indeed, the enhancement of NO production elicited by androgen was associated with EC growth. The steroid significantly increased DNA synthesis after 24 h of treatment, and this mitogenic action was blunted in the presence of NO synthase inhibitor N-nitro-l-arginine methyl ester. In summary, testosterone modulates vascular EC growth and platelet aggregation through its direct action on endothelial NO production. PMID: 22281525 Canonico M, Oger E, Plu-Bureau G, Conard J, Meyer G, Levesque H, Trillot N, Barrellier MT, Wahl D, Emmerich J, Scarabin PY; Estrogen and Thromboembolism Risk (ESTHER) Study Group. Hormone therapy and venous thromboembolism among postmenopausal women: impact of the route of estrogen administration and progestogens: the ESTHER study. Circulation. 2007 Feb 20;115(7):840-5. BACKGROUND: Oral estrogen therapy increases the risk of venous thromboembolism (VTE) in postmenopausal women. Transdermal estrogen may be safer. However, currently available data have limited the ability to investigate the wide variety of types of progestogen. METHODS AND RESULTS: We performed a multicenter case-control study of VTE among postmenopausal women 45 to 70 years of age between 1999 and 2005 in France. We recruited 271 consecutive cases with a first documented episode of idiopathic VTE (208 hospital cases, 63 outpatient cases) and 610 controls (426 hospital controls, 184 community controls) matched for center, age, and admission date. After adjustment for potential confounding factors, odds ratios (ORs) for VTE in current users of oral and transdermal estrogen compared with nonusers were 4.2 (95% CI, 1.5 to 11.6) and 0.9 (95% CI, 0.4 to 2.1), respectively. There was no significant association of VTE with micronized progesterone and pregnane derivatives (OR, 0.7; 95% CI, 0.3 to 1.9 and OR, 0.9; 95% CI, 0.4 to 2.3, respectively). In contrast, norpregnane derivatives were associated with a 4-fold-increased VTE risk (OR, 3.9; 95% CI, 1.5 to 10.0). CONCLUSIONS: Oral but not transdermal estrogen is associated with an increased VTE risk. In addition, our data suggest that norpregnane derivatives may be thrombogenic, whereas micronized progesterone and pregnane derivatives appear safe with respect to thrombotic risk. If confirmed, these findings could benefit women in the management of their menopausal symptoms with respect to the VTE risk associated with oral estrogen and use of progestogens. Canonico M, Fournier A, Carcaillon L, Olié V, Plu-Bureau G, Oger E, Mesrine S, Boutron-Ruault MC, Clavel-Chapelon F, Scarabin PY. Postmenopausal hormone therapy and risk of idiopathic venous thromboembolism: results from the E3N cohort study. Arterioscler Thromb Vasc Biol. 2010 Feb;30(2):340-5. OBJECTIVE: Oral estrogen therapy increases venous thromboembolism risk among postmenopausal women. Although recent data showed transdermal estrogens may be safe with respect to thrombotic risk, the impact of the route of estrogen administration and concomitant progestogens is not fully established. METHODS AND RESULTS: We used data from the E3N French prospective cohort of women born between 1925 and 1950 and biennially followed by questionnaires from 1990. Study population consisted of 80 308 postmenopausal women (average follow-up: 10.1 years) including 549 documented idiopathic first venous thromboembolism. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox proportional models. Compared to never-users, past-users of hormone therapy had no increased thrombotic risk (HR=1.1; 95% CI: 0.8 to 1.5). Oral not transdermal estrogens were associated with increased thrombotic risk (HR=1.7; 95% CI: 1.1 to 2.8 and HR=1.1; 95% CI: 0.8 to 1.8; homogeneity: P=0.01). The thrombotic risk significantly differed by concomitant progestogens type (homogeneity: P<0.01): there was no significant association with progesterone, pregnanes, and nortestosterones (HR=0.9; 95% CI: 0.6 to 1.5, HR=1.3; 95% CI: 0.9 to 2.0 and HR=1.4; 95% CI: 0.7 to 2.4). However, norpregnanes were associated with increased thrombotic risk (HR=1.8; 95% CI: 1.2 to 2.7). CONCLUSIONS: In this large study, we found that route of estrogen administration and concomitant progestogens type are 2 important determinants of thrombotic risk among postmenopausal women using hormone therapy. Transdermal estrogens alone or combined with progesterone might be safe with respect to thrombotic risk. PMID: 19834106 Carta G, Iovenitti P, Falciglia K. Recurrent miscarriage associated with antiphospholipid antibodies: prophylactic treatment with low-dose aspirin and fish oil derivates. Clin Exp Obstet Gynecol. 2005;32(1):49-51. PROBLEM: The aim of this study was to evaluate the effects of two different prophylactic protocols, low-dose aspirin and fish oil derivates, in the treatment of patients with recurrent pregnancy loss associated with antiphospholipid antibodies (APA) syndrome. METHODS: A prospective study included 30 patients who were alternately assigned to treatment. Each patient had had at least two consecutive spontaneous abortions, positive antiphospholipid antibodies on two occasions, and a complete evaluation. RESULTS: Among patients treated with low-dose aspirin, 12 out of the 15 (80%) pregnancies ended in live births. In the fish oil derivate group 11 out of the 15 (73.3%) ended in live births (p > 0.05). There were no significant differences between the low-dose aspirin and the fish oil derivates groups with respect to gestational age at delivery (39.9 +/- 0.4 vs 39 +/- 1.5 weeks), fetal birth weight (3290 +/- 200g vs 3560 +/- 100 g), number of cesarean sections (25% vs 18%), or complications. CONCLUSION: There were no significant differences in terms of pregnancy outcome between women with recurrent pregnancy loss associated with APA syndrome treated with low-dose aspirin or fish oil derivates.(Usual rate of fetal loss is 90% in untreated women with APL (Rai 1997). Suppression of APL with Prednisone also prevents spontaneous abortions (Lubbe 1983).-HHL) De Pergola G, De Mitrio V, Sciaraffia M, Pannacciulli N, Minenna A, Giorgino F, Petronelli M, Laudadio E, Giorgino R. Lower androgenicity is associated with higher plasma levels of prothrombotic factors irrespective of age, obesity, body fat distribution, and related metabolic parameters in men. Metabolism. 1997 Nov;46(11):1287-93. The purpose of this study was to examine the relationships between androgenic status and plasma levels of both prothrombotic and antithrombotic factors in men, irrespective of obesity, body fat distribution, and metabolic parameters. Sixty-four apparently healthy men, 40 with a body mass index (BMI) greater than 25 kg/m2 (overweight and obese [OO]) and 24 non-obese controls with a BMI less than 25, were selected and evaluated for (1) plasma concentrations of plasminogen activator inhibitor-1 (PAI-1) antigen, PAI-1 activity, fibrinogen, von Willebrand factor (vWF) antigen, vWF activity, and factor VII (FVII) as the prothrombotic factors; (2) plasma levels of tissue plasminogen activator (TPA) antigen, protein C, and antithrombin III as the antithrombotic factors; (3) fasting plasma concentrations of insulin and glucose and the lipid pattern (triglycerides [TG] and total and high-density lipoprotein [HDL] cholesterol) as the metabolic parameters; and (4) free testosterone (FT), dehydroepiandrosterone sulfate (DHEAS), and sex hormone-binding globulin (SHBG) serum levels as the parameters of androgenicity. Body fat distribution was evaluated by the waist to hip ratio (WHR). In OO and non-obese subjects taken together, plasma levels of PAI-1 antigen, fibrinogen, and FVII were inversely associated with FT (r = .255, P < .05, r = -3.14, P < .05, and r = -.278, P < .05, respectively), and the negative relationships of both fibrinogen and FVII with FT were maintained after stepwise multiple regression analysis. Plasma concentrations of PAI-1 antigen and PAI-1 activity were also negatively correlated with SHBG (r = -.315, P < .05 and r = -.362, P < .01, respectively), and these associations held irrespective of the other parameters investigated. None of the antithrombotic and fibrinolytic factors were independently related to serum androgen levels. Subjects with a BMI higher than 25 kg/m2 had higher plasma concentrations of PAI-1 antigen, PAI-1 activity, and fibrinogen as compared with non-obese controls (P < .001, P < .001, and P < .01, respectively). In addition, in OO and control subjects as a whole, multiple stepwise regression analysis showed that the associations of BMI with PAI-1 activity, fibrinogen, vWF antigen, and vWF activity were independent of any other metabolic and hormonal parameters. Plasma concentrations of PAI-1 antigen, PAI-1 activity, and fibrinogen were also directly correlated with WHR in all subjects taken together, irrespective of the other parameters investigated. Evaluation of antithrombotic factors showed that OO subjects had higher TPA plasma concentrations than non-obese controls (P < .001), whereas protein C and antithrombin III did not differ in the two groups. TPA was also directly correlated with BMI (r = .415, P < .001) and WHR (r = .393, P < .001) in all subjects. The results of this study indicate that (1) men with lower FT serum levels have higher fibrinogen and FVII plasma concentrations, and those with lower SHBG serum levels also have higher levels of PAI-1 antigen and activity; (2) irrespective of other factors, obesity per se may account for higher concentrations of PAI-1, fibrinogen, and vWF; (3) plasma levels of PAI-1 (antigen and activity) and fibrinogen correlate independently with WHR; and (4) among the investigated antithrombotic factors (TPA antigen, protein C, antithrombin III), only TPA antigen plasma concentrations are higher in men with abdominal obesity. Thus, because of the increase in several prothrombotic factors, men with central obesity, particularly those with lower androgenicity, seem to be at greater risk for coronary heart disease (CHD). Apparently, this risk is not counteracted by a parallel increase in plasma concentrations of antithrombotic factors. PMID: 9361687 Di Nisio M, Barbui T, Di Gennaro L, Borrelli G, Finazzi G, Landolfi R, Leone G, Marfisi R, Porreca E, Ruggeri M, Rutjes AW, Tognoni G, Vannucchi AM, Marchioli R; European Collaboration on Low-dose Aspirin in Polycythemia Vera (ECLAP) Investigators. The haematocrit and platelet target in polycythemia vera. Br J Haematol. 2007 Jan;136(2):249-59. Polycythemia vera (PV) is a chronic myeloproliferative disorder whose major morbidity and mortality are thrombohaemorragic events and progression to acute leukaemia or myelofibrosis. Whether the haematocrit and platelet count predict such complications remains unclear. The European Collaboration on Low-dose Aspirin in Polycythemia Vera prospective study included 1638 PV patients. A total of 164 deaths (10%), 145 (8.85%) major thrombosis and 226 (13.8%) total thrombosis were encountered during 4393 person-years follow-up (median 2.8 years). In time-dependent multivariable analysis, a haematocrit in the evaluable range of 40-55% was neither associated with the occurrence of thrombotic events, mortality nor with haematological progression in the studied population. The haematocrit of patients in the highest and lowest deciles at baseline was maintained within a narrow interval of haematocrit values ranging from 40% to 47% throughout follow-up. High platelet count was associated with a lower progression rate to acute leukaemia/myelofibrosis, whereas it had no significant relationship with thrombotic events or mortality. Our findings do not suggest that the range of haematocrit (<55%) and platelet counts (<600 x 10(9)/l) we encountered in our population had an impact on the outcome of PV patients treated by current therapeutic strategies. PMID: 17156406 Erem C, Kocak M, Hacihasanoglu A, Yilmaz M. Blood coagulation and fibrinolysis in male patients with hypogonadotropic hypogonadism: plasma factor V and factor X activities increase in hypogonadotropic hypogonadism. J Endocrinol Invest. 2008 Jun;31(6):537-41. BACKGROUND AND OBJECTIVES: In men, androgens have both pro- and anti-thrombotic effects. Androgen deficiency in men is associated with an increased incidence of cardiovascular disease (CVD). However, the influence of hypogonadism on hemostasis is controversial. Little is known about hemostatic features of male patients with idiopathic hypogonadotropic hypogonadism (IHH). Thus, the aim of the present study was to evaluate the markers of endogenous coagulation and fibrinolysis, and to investigate the relationships between endogenous sex hormones and hemostatic parameters and serum lipid profile in men with IHH. DESIGN AND METHODS: Seventeen patients with IHH and 20 age-matched healthy controls were included in the study. Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, factors (F) V, VII, VIII, IX, and X activities, von Willebrand factor (vWF), antithrombin III (AT III), protein C, protein S, tissue plasminogen activator (t-PA), and tissue plasminogen activator inhibitor (PAI-1), as well as common lipid variables, were measured. The relationships between serum sex hormones and these hemostatic parameters were examined. RESULTS: Compared with the control subjects, platelet count, FV, FX, and protein C activities were significantly increased in patients with IHH (p<0.01, p<0.05, p<0.01, and p<0.05, respectively), whereas AT III was decreased (p<0.05). Fibrinogen, FVIII, vWF, t-PA, PAI-1, and the other coagulation/fibrinolysis parameters and lipid profile in patients with IHH were not different from the controls. In patients with IHH, we showed that serum LH level was negatively correlated with fibrinogen (r: -0.78, p<0.01) and protein C (r: -0.55, p<0.05) and positively correlated with t-PA (r: 0.53, p<0.05). Serum FSH levels inversely correlated with fibrinogen (r: -0.75, p<0.01). INTERPRETATION AND CONCLUSIONS: |