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Relationship between hemostasis and hyperhomocysteinemia induced by methionine loading in vitamin B6 and folate deficiency
Monday June 26, 2000: Read by Title Abstracts T.'W2 Thrombosis and Fibrinolysis
70
Concnsion: Plasmin generation is reduced in the patients with HTG, although TG is positively correlated with PAI-1 and tPA. Increased tPA level proportional to PAI-I is interpreted as a compensatory augmentation for inhibitory effect of plasmin conversion by PAI-1. On the contrary, the patients with low HDL.c have enhanced plasmin generation independent of tPA and increased free-TFPl. Enhanced fibrinolytic activity and anti-thrombotic property in low HDL.c suggests compensatory responses against atherothromobotic milieu derived from decreased vascular protective function by HDL particle. I MoT2:W2 I Relationship between hemostasis and
hyperhomocysteinemia induced by methionine loading in vitamin B6 and folate deficiency S.-J. Chang, C.Y. Liao, Y.-C. Li. Department of Biology, National Cheng Kung University, Tainan, Taiwan, ROC
Background: There is increasing evidence that hyperhomocysteinemia (HHcy) is an independent risk factor for thrombosis. The mechanism that increased tendency of thrombosis associated with HHcy is not clear. Imbalance of hemostatlc system may contribute to thrombosis. Objective: To measure plasma concentration of homocysteine (Hey) and investigate the relationship between Hcy level and clotting factors in vitamin B6 and folate deficient rats loaded with methionine (Met). Methods: Sprague-Dawley rats fed with control (Ctl), vitamin B6 deficient (B6D), folate deficient (FD) or vitamin B6 plus folate deficient (B6FD) diet were injected with either saline (0.9%) or Met (0.1 g/kg body weight) and blood sample was collected 2 hours thereafter. Plasma Hey concentration was quantified by HPLC after derivatized with SBD-F. Clotting factors including antithrombin IlI (AT III) protein C (PC) plasminogen (PLG) and plasma concentration of heparin were determined by a chromogenic assay with a chromogenic kinetic system device. Results: Plasma Hey concentrations of B6D FD and B6FD rats were significantly higher than that of Ctl rats (B6D = 25.17 4- 4.38/~M, FD = 24.96 =i= 4.08/~M, B6FD = 33.33 4- 1.33/~M, Ctl = 3.41 =E 0.23 #M, p < 0.01). Plasma Hey concentrations were negatively correlated to AT III (r = -0.98, p < 0.05) PC (r = -0.95, p < 0.05) and PLG levels (r = -0.72, p < 0.05). However, no correlation between plasma Hey concentration and heparin level was found. Conclusions: We suggest that HHcy induced by Met alters plasma concentrations of clotting factors and may contribute to the imbalance of hemostasis in vitamin B6 and folate deficient status.
I MOT4:W2 I Thrombogenetic risk factors in patients with thrombangitis
obUterans M. Brodmann, W. Rennet, G. Stark, M. Winkler, E. Pabst, C. Hofmann, H. K6ppel, E. Pilger. Division of Angiolgy, Department of Internal Medicine,
University Hospital Graz, Austria Objective: Thrombangitis obliterans (TAO) is a segmental inflammatory occlusive disease which primarly affects small or medium sized arteries and veins in the extremities of young adults who have a history of heavy smoking. As it is a fact in histological findings in arteries of patients with TAO that the segmental inflammatory process in the vessel wall is accompanied by a thrombotic occlusion in the arteries, we saw the purpose of our study to evaluate if prothrombotic risk factors can be found in patients suffering from TAO at a higher level than in a control group lacking deep venous thrombosis or arterial disease. Methods: 28 patients (17 male and 11 female) with a history of TAO were enrolled in our study. All patients were evaluated for the following thrombogenic risk factors: antithrombin HI, protein C, protein S, cardiolipin antibodies, lupus anticoagulans, Factor V Leiden (F5 1691A), Prothromhin 20210 A (F2 20210A) and Factor XIII Va134Leu (F13 100T). Results: F2 20210A alleles were more frequent but not statistically significant among patients than among controls (7.1% versus 3.4%). None of the patients had a homozygous status of F2 20210A mutation. F5 1691A alleles tended to be less frequent among patients than among controls (3.6 versus 9.4%), but did not reach significance. None of the patients had a homozygous status of F5 1619A mutation. F13 100T alleles were equally frequent for the heterozygous status among patients and controls (39.6% versus 38.3%) but showed a trend of being more frequent in the homozygous status in the patients group than in the control group. (10.8% versus 7.1%) The difference was not statistically signifcant, None of the evaluated patients showed either a deficiency of antithrombin III, protein C and S, or elavated cardiolipin antibodies IgM and IgG or a lupus anticoagulans. Conclusions: Out of the presented data it is possible to conclude that prothombotic risk factors are not involved in the pathogenesis of TAO
I MoT5:W2 I[ Effects of atorvastatin on fibrinolytic system in patients with familial hypercholesterolemia L. Pucci, S. Bandinelli, D. Lucchesi, E Caricato, R. Navalesi, A. Bertolotto, G. Penno. Endocrinology and Metabolism, Pisa, Italy
Objective: Fibrinolysis is mainly regulated by a balance between tPA and MoT3:W2 [ Increased prevalence of haemostatic abnormalities and osteoarthritis (OA) in a young cohort of patients with coronary heart disease (CHD) and hyperlipidemia I
D.M. Colquhoun2, P.A. Cheras 1, G.V.L. Nielsen I , P. Dubois 1, H.K. Outerbridge 1, D. Battistutta3 . IGreenslopes Hospital; 2Core Research,"
3QUT, Brisbane, Australia Objective: To investigate associations between CHD and OA. Method: Patients (pts) with mixed hyperlipidemia (MH) and CHD were compared with a frequency and age matched control group (C) with no clinical signs of OA and a group of pts with X-ray confirmed OA but without clinical CHD. 20 pts, mean age 47 years (22-59) with MH and CHD were enrolled. These were compared with 23 OA pts and 29 volunteer controls. Presence or absence of OA in the MH/CHD group was based on of X-rays of the hips and knees read by two blinded researchers. Fasting bloods were analysed for haemostatic factors. Ordinal logistic regression modelling assessed associations after adjustment for residual age and sex effects. Results: 13 of 20 CHD pts were X-ray positive for OA. Test BMI BP sy BP di CHOL HDL LDL TG
C
OA
CHD
Test
C
OA
CHD
24.6 121 77 4.91 1.25 3.23 0.93
27.8 126 83*** 5.75** 1.34 3.73 1.51"**
29*** 127"** 83** 8.20*** 0.96*** 5.36*** 4.37**
PrC ECLT t-PA PAI-I ~t2AP Lp(a)
104 145 0.67 6.5 92 148
122'** 167 m 0.60 11.6"* 104' 230
149"* 205* 0.44*** 19.1"** 112"** 493
PAI-1. Decreased fibrinolysis is linked with increased PAI-1 and tPA antigen levels, the last reflecting mainly tPA/PAI-1 complexes. We aimed to evaluate the effects of atorvastatin on plasma tPA and PAI- 1 antigen levels. Methods: Twenty-two non-diabetic patients with familial hypercholesterolemia (FH; 14 M, 8 F; 49 4- 7.8 years-old; BMI 25.2 -F 3.2 kg/m 2) discontinued their lipid lowering drugs for at least 6 weeks. At baseline, after 1 month (atorvastatin 20 mg/day) and 6 months (40 rag/day), fasting lipids, tPA Ag, PAI-1 Ag (TindElize tPA and TintElyze PAI-1, Biopool, Sweden) were measured. Twenty-two healthy subjects acted as controls. ANOVA for repeated measures was used to study the effects on lipids, tPA and PAI-I Ag levels. Results: Atorvastatin reduced total-ch by 39% (373 -4- 44 rag/all at baseline vs 250 -4- 30 and 229 -4- 30 mg/dl after 4 and 24 weeks, respectively, p < 0.0001); LDL by 46% (296 -4- 45 vs 181 -4- 33 and 159 -4- 33 mg/dl, p < 0.0OO1); Apo-B by 39% (220 4- 30 vs 155 -4- 25 and 134 -4- 26 mg/dl, p < 0.0001) and triglycerides by 23% (136 + 58 vs 104 -4- 45 and 101 -4- 45 mg/dl, p < 0.005). No changes in HDL (50 4- 11, 49 5= 11 and 50 -4- 11 mg/dl) and apo-A1 (141 -4- 19, 140 -4- 26 and 146 -4- 27 mg/dl) were observed. Baseline tPA and PAI-1 Ag levels were higher in FH than in controls (tPA 9.4 -4- 4.5 vs 7.3 -4- 2.8 ng/ml, p = 0.019; PAI-1 28.9 4- 15.4 vs 19.4 4- 14.6 ng/ml, p = 0.032). tPA and PAI-1 levels did not change after 4 weeks of therapy (tPA 10.9 4- 5 ng/ml; PAI-1 25.9 4- 16.1 ng/ml) while significantly reduced themselves after 24 weeks (tPA 7.7 -4- 3.7 ng/ml, p = 0.035; PAW 19.6 4- 8.6 ng/ml, p = 0.037). Conclusions: Atorvastatin, an highly effective drug in reducing LDL in FH, seems to have a promising role in regulating fibrinolysis.
*p < 0.05; **p < 0,01; ***p < 0.0OI
Conclusions: OA in the MH/CHD group is significantly more prevalent than expected. A strong association exists between hyperlipidemia and haemostatic risk factors in CHD pts. These haemostatic risk factors are also associated with OA in non-CHD pts.
Xllth International Symposium on Atherosclerosis, Stockholm, Sweden, June 25-29, 2000
70
Concnsion: Plasmin generation is reduced in the patients with HTG, although TG is positively correlated with PAI-1 and tPA. Increased tPA level proportional to PAI-I is interpreted as a compensatory augmentation for inhibitory effect of plasmin conversion by PAI-1. On the contrary, the patients with low HDL.c have enhanced plasmin generation independent of tPA and increased free-TFPl. Enhanced fibrinolytic activity and anti-thrombotic property in low HDL.c suggests compensatory responses against atherothromobotic milieu derived from decreased vascular protective function by HDL particle. I MoT2:W2 I Relationship between hemostasis and
hyperhomocysteinemia induced by methionine loading in vitamin B6 and folate deficiency S.-J. Chang, C.Y. Liao, Y.-C. Li. Department of Biology, National Cheng Kung University, Tainan, Taiwan, ROC
Background: There is increasing evidence that hyperhomocysteinemia (HHcy) is an independent risk factor for thrombosis. The mechanism that increased tendency of thrombosis associated with HHcy is not clear. Imbalance of hemostatlc system may contribute to thrombosis. Objective: To measure plasma concentration of homocysteine (Hey) and investigate the relationship between Hcy level and clotting factors in vitamin B6 and folate deficient rats loaded with methionine (Met). Methods: Sprague-Dawley rats fed with control (Ctl), vitamin B6 deficient (B6D), folate deficient (FD) or vitamin B6 plus folate deficient (B6FD) diet were injected with either saline (0.9%) or Met (0.1 g/kg body weight) and blood sample was collected 2 hours thereafter. Plasma Hey concentration was quantified by HPLC after derivatized with SBD-F. Clotting factors including antithrombin IlI (AT III) protein C (PC) plasminogen (PLG) and plasma concentration of heparin were determined by a chromogenic assay with a chromogenic kinetic system device. Results: Plasma Hey concentrations of B6D FD and B6FD rats were significantly higher than that of Ctl rats (B6D = 25.17 4- 4.38/~M, FD = 24.96 =i= 4.08/~M, B6FD = 33.33 4- 1.33/~M, Ctl = 3.41 =E 0.23 #M, p < 0.01). Plasma Hey concentrations were negatively correlated to AT III (r = -0.98, p < 0.05) PC (r = -0.95, p < 0.05) and PLG levels (r = -0.72, p < 0.05). However, no correlation between plasma Hey concentration and heparin level was found. Conclusions: We suggest that HHcy induced by Met alters plasma concentrations of clotting factors and may contribute to the imbalance of hemostasis in vitamin B6 and folate deficient status.
I MOT4:W2 I Thrombogenetic risk factors in patients with thrombangitis
obUterans M. Brodmann, W. Rennet, G. Stark, M. Winkler, E. Pabst, C. Hofmann, H. K6ppel, E. Pilger. Division of Angiolgy, Department of Internal Medicine,
University Hospital Graz, Austria Objective: Thrombangitis obliterans (TAO) is a segmental inflammatory occlusive disease which primarly affects small or medium sized arteries and veins in the extremities of young adults who have a history of heavy smoking. As it is a fact in histological findings in arteries of patients with TAO that the segmental inflammatory process in the vessel wall is accompanied by a thrombotic occlusion in the arteries, we saw the purpose of our study to evaluate if prothrombotic risk factors can be found in patients suffering from TAO at a higher level than in a control group lacking deep venous thrombosis or arterial disease. Methods: 28 patients (17 male and 11 female) with a history of TAO were enrolled in our study. All patients were evaluated for the following thrombogenic risk factors: antithrombin HI, protein C, protein S, cardiolipin antibodies, lupus anticoagulans, Factor V Leiden (F5 1691A), Prothromhin 20210 A (F2 20210A) and Factor XIII Va134Leu (F13 100T). Results: F2 20210A alleles were more frequent but not statistically significant among patients than among controls (7.1% versus 3.4%). None of the patients had a homozygous status of F2 20210A mutation. F5 1691A alleles tended to be less frequent among patients than among controls (3.6 versus 9.4%), but did not reach significance. None of the patients had a homozygous status of F5 1619A mutation. F13 100T alleles were equally frequent for the heterozygous status among patients and controls (39.6% versus 38.3%) but showed a trend of being more frequent in the homozygous status in the patients group than in the control group. (10.8% versus 7.1%) The difference was not statistically signifcant, None of the evaluated patients showed either a deficiency of antithrombin III, protein C and S, or elavated cardiolipin antibodies IgM and IgG or a lupus anticoagulans. Conclusions: Out of the presented data it is possible to conclude that prothombotic risk factors are not involved in the pathogenesis of TAO
I MoT5:W2 I[ Effects of atorvastatin on fibrinolytic system in patients with familial hypercholesterolemia L. Pucci, S. Bandinelli, D. Lucchesi, E Caricato, R. Navalesi, A. Bertolotto, G. Penno. Endocrinology and Metabolism, Pisa, Italy
Objective: Fibrinolysis is mainly regulated by a balance between tPA and MoT3:W2 [ Increased prevalence of haemostatic abnormalities and osteoarthritis (OA) in a young cohort of patients with coronary heart disease (CHD) and hyperlipidemia I
D.M. Colquhoun2, P.A. Cheras 1, G.V.L. Nielsen I , P. Dubois 1, H.K. Outerbridge 1, D. Battistutta3 . IGreenslopes Hospital; 2Core Research,"
3QUT, Brisbane, Australia Objective: To investigate associations between CHD and OA. Method: Patients (pts) with mixed hyperlipidemia (MH) and CHD were compared with a frequency and age matched control group (C) with no clinical signs of OA and a group of pts with X-ray confirmed OA but without clinical CHD. 20 pts, mean age 47 years (22-59) with MH and CHD were enrolled. These were compared with 23 OA pts and 29 volunteer controls. Presence or absence of OA in the MH/CHD group was based on of X-rays of the hips and knees read by two blinded researchers. Fasting bloods were analysed for haemostatic factors. Ordinal logistic regression modelling assessed associations after adjustment for residual age and sex effects. Results: 13 of 20 CHD pts were X-ray positive for OA. Test BMI BP sy BP di CHOL HDL LDL TG
C
OA
CHD
Test
C
OA
CHD
24.6 121 77 4.91 1.25 3.23 0.93
27.8 126 83*** 5.75** 1.34 3.73 1.51"**
29*** 127"** 83** 8.20*** 0.96*** 5.36*** 4.37**
PrC ECLT t-PA PAI-I ~t2AP Lp(a)
104 145 0.67 6.5 92 148
122'** 167 m 0.60 11.6"* 104' 230
149"* 205* 0.44*** 19.1"** 112"** 493
PAI-1. Decreased fibrinolysis is linked with increased PAI-1 and tPA antigen levels, the last reflecting mainly tPA/PAI-1 complexes. We aimed to evaluate the effects of atorvastatin on plasma tPA and PAI- 1 antigen levels. Methods: Twenty-two non-diabetic patients with familial hypercholesterolemia (FH; 14 M, 8 F; 49 4- 7.8 years-old; BMI 25.2 -F 3.2 kg/m 2) discontinued their lipid lowering drugs for at least 6 weeks. At baseline, after 1 month (atorvastatin 20 mg/day) and 6 months (40 rag/day), fasting lipids, tPA Ag, PAI-1 Ag (TindElize tPA and TintElyze PAI-1, Biopool, Sweden) were measured. Twenty-two healthy subjects acted as controls. ANOVA for repeated measures was used to study the effects on lipids, tPA and PAI-I Ag levels. Results: Atorvastatin reduced total-ch by 39% (373 -4- 44 rag/all at baseline vs 250 -4- 30 and 229 -4- 30 mg/dl after 4 and 24 weeks, respectively, p < 0.0001); LDL by 46% (296 -4- 45 vs 181 -4- 33 and 159 -4- 33 mg/dl, p < 0.0OO1); Apo-B by 39% (220 4- 30 vs 155 -4- 25 and 134 -4- 26 mg/dl, p < 0.0001) and triglycerides by 23% (136 + 58 vs 104 -4- 45 and 101 -4- 45 mg/dl, p < 0.005). No changes in HDL (50 4- 11, 49 5= 11 and 50 -4- 11 mg/dl) and apo-A1 (141 -4- 19, 140 -4- 26 and 146 -4- 27 mg/dl) were observed. Baseline tPA and PAI-1 Ag levels were higher in FH than in controls (tPA 9.4 -4- 4.5 vs 7.3 -4- 2.8 ng/ml, p = 0.019; PAI-1 28.9 4- 15.4 vs 19.4 4- 14.6 ng/ml, p = 0.032). tPA and PAI-1 levels did not change after 4 weeks of therapy (tPA 10.9 4- 5 ng/ml; PAI-1 25.9 4- 16.1 ng/ml) while significantly reduced themselves after 24 weeks (tPA 7.7 -4- 3.7 ng/ml, p = 0.035; PAW 19.6 4- 8.6 ng/ml, p = 0.037). Conclusions: Atorvastatin, an highly effective drug in reducing LDL in FH, seems to have a promising role in regulating fibrinolysis.
*p < 0.05; **p < 0,01; ***p < 0.0OI
Conclusions: OA in the MH/CHD group is significantly more prevalent than expected. A strong association exists between hyperlipidemia and haemostatic risk factors in CHD pts. These haemostatic risk factors are also associated with OA in non-CHD pts.
Xllth International Symposium on Atherosclerosis, Stockholm, Sweden, June 25-29, 2000