Stromelysin-1 5A/6A and eNOS T-786C polymorphisms, MTHFR C677T and A1298C mutations, and cigarette-cannabis smoking: a pilot, hypothesis-generating study of gene-environment pathophysiological associations with Buerger's disease.

Buerger's disease (BD) etiologies are poorly understood. Beyond smoking cessation, medical-surgical treatments have limited success. We hypothesized that mutations associated with arterial vasospasm (stromelysin-1 5A/6A, eNOS T-786C) and C677T-A1298C methylene tetrahydrofolate reductase (MTHFR) interacted with cigarette-cannabis smoking, reducing vasodilatory nitric oxide (NO), promoting arterial spasm-thrombosis. Of 21 smoking BD patients (14 men [2 siblings], 7 women; 20 white, 1 African-American), compared to 21 age-gender-race matched healthy controls, 5A/6A stromelysin- 1 homozygosity was present in 7 of 21 (33%) BD cases versus 5 of 21 (24%) controls (risk ratio 1.4; 95% confidence interval [CI] 0.5-3.7), and eNOS T-786C homozygosity was present in 3 of 21 (14%) BD cases versus 1 of 21 (5%) controls (risk ratio 3.0; 95% CI 0.3-26.6). C677T MTHFR homozygosity or compound C677T-A1298C heterozygosity was present in 7 of 21 cases (33%) versus 11 of 21 controls (52%) (risk ratio 0.6; 95% CI 0.3-1.3). In 18 patients who stopped and 3 who continued smoking, all stromelysin-1 5A/6A and/or eNOS heterozygotes-homozygotes, superficial phlebitis, lower limb gangrenous ulcers, and intractable ischemic rest pain with arterial occlusion progressed despite conventional medical therapy, threatening amputation. In 15 patients, to increase vasodilatory NO via endothelial NO synthase, l-arginine (15 g/day) was given, along with folic acid (5 mg), vitamin B6 (100 mg), and B12 (2000 mg/day) to optimize homocysteine metabolism and reduce asymmetric dimethylarginine, a NO synthase inhibitor. Unexpectedly quickly and strikingly, within 8 weeks to 8 months receiving l-arginine-folic acid, 11 of 15 treated patients improved with uniform pain reduction, ulcer healing, and in 5, full recovery of previously absent peripheral pulses. In smokers homo/heterozygous for stromelysin-1 5A/6A and eNOS T-786C mutations, we speculate that the development and severity of BD are related to a gene-environment vasospastic interaction with reduced NO-mediated vasodilatation. Increasing NO production by l-arginine while optimizing homocysteine metabolism by folic acid-B6-B12 may have therapeutic benefit. Further blinded, placebo-controlled studies are needed to determine whether our observations can be generalized to larger BD cohorts.

The factor V Leiden mutation, high factor VIII, and high plasminogen activator inhibitor activity: etiologies for sporadic miscarriage.

We hypothesized that the thrombophilic G1691A factor V Leiden gene mutation was a common significant cause of sporadic first trimester miscarriage. We compared thrombophilia and hypofibrinolysis in 92 women (85 white, 5 black, 2 other) with 1 or more pregnancies and 1 miscarriage (143 live births, 92 miscarriages) (cases) and in 380 female controls (355 white, 21 black, 4 other) with 1 or more pregnancies and 0 miscarriages (964 live births). We used polymerase chain reaction techniques to characterize thrombophilic gene mutations (G1691A V Leiden [FV], G20210A prothrombin, C677T/A1298C MTHFR) and hypofibrinolytic gene mutations (plasminogen activator inhibitor [PAI-1] activity 4G4G). We carried out serologic measures of thrombophilia (homocysteine, anticardiolipin antibodies [ACLA] immunoglobulin G and immunoglobulin M, lupus anticoagulant, factor VIII, factor XI, protein C, total and free protein S, antithrombin III) and hypofibrinolysis (plasminogen activator inhibitor activity [PAI-Fx], lipoprotein[a]). Of the 380 controls, 6 (1.6%) had FV heterozygosity vs 12 heterozygous and 2 homozygous FV cases (15.2% [14/92]; P < .0001). Plasminogen activator inhibitor activity was high (> or =21.1 U/mL) in 21 (33%) of 63 cases vs 27 (18%) of 152 controls (P = .013). Factor VIII was high (>150%) in 15 (31%) of 48 cases vs 19 (18%) of 103 controls (P = .079). By logistic regression, with age and factor VIII (categorical [< or =150%, >150%]) as explanatory variables and group (cases, controls) as the dependent variable, after adjusting for age, high factor VIII was a significant predictor for miscarriage (odds ratio, 3.28; 95% confidence interval, 1.34-8.04; P = .01). There were no other group differences (P > .05) in measures of thrombophilia and hypofibrinolysis. After unexplained sporadic first trimester miscarriage, we suggest that measurements be done of the FV mutation, PAI-Fx, and factor VIII, etiologies for sporadic miscarriage.