The Effect of Dietary Intervention Through the Modification of Fatty Acids Composition and Antioxidant Vitamin Intake on Plasma TXB2 Level in Korean Postmenopausal Women with Hypercholesterolemia

The purpose of this study was to observe the effects of dietary intervention, through the modification of dietary fatty acids composition and antioxidant vitamins, on plasma thromboxane B2 (TXB2) levels in postmenopausal women with hypercholesterolemia. The subjects were treated for 12 weeks with one of three methods: hormone replacement therapy (HRT group, n=8), dietary intervention (DIET group, n=8), or HRT combined with dietary intervention (HRT +DIET group, n=8). Changes in serum phospholipid fatty acids composition, serum peroxides, and plasma TXB2 levels were measured at weeks 0, 4 and 12. The P/S ratio increased and the n-6/ n-3 ratio decreased in the DIET and the HRT +DIET group at week 4 (p<0.05). The ratio of C20:5/C20:4 in serum phospholipid increased in the DIET (p<0.05) and the HRT +DIET groups (NS) at week 4. Plasma TXB2 levels decreased in the DIET (-35%, p<0.05) and the HRT +DIET groups (-18.8%, NS) at week 4. Serum lipid peroxides levels significantly decreased by 10.5% and 15.2% in the DIET group at weeks 4 and 12, and by 10.8% in the HRT +DIET group only at week 12 (p<0.05). Dietary intervention may lower thrombotic risks in Korean postmenopausal women by changing the serum fatty acid composition, serum lipid peroxides levels and plasma thromboxane B2 levels.

Tromboxano B2 y factor de crecimiento derivado de las plaquetas en la trombocitemia esencial tratada con anagrelide / Thromboxane B2 and platelet derived growth factor in essential thrombocythemia treated with anagrelide

Presentamos los resultados obtenidos en 17 pacientes con trombocitemia esencial antes del tratamiento con anagrelide y durante la remisión hematológica y clínica inducida por esta droga. Diez pacientes tenían manifestaciones clínicas relacionadas con la trombocitemia, en 8 de ellos al momento de iniciar el tratamiento. Se midieron los niveles plasmáticos del TXB2 y del PDGF por técnica de ELISA. Antes del tratamiento los valores plasmáticos del PDGF corregidos por el recuento de plaquetas eran significativamente menores que en los controles (p = 0.02), y no difirieron de los resultados obtenidos durante la remisión. En cambio, los valores plasmáticos del TXB2, corregidos de acuerdo al recuento de plaquetas, estaban más elevados que en los controles (p = 0.04), y disminuyeron significativamente durante la remisión (p = 0.04), aunque todavía estaban por sobre los valores normales (p = 0.008). Los síntomas desaparecieron en todos los pacientes cuando el recuento de plaquetas se normalizó. Estos resultados muestran que los pacientes con trombocitemia esencial tratados con anagrelide y en remisión hematológica y clínica tienen tendencia a normalizar los niveles del TXB2.

Early prediction of preeclampsia by measurement of plasma endothelin-1 and thromboxane- beta 2 in high risk pregnancy

The aim of this study was to investigate the predictive value of plasma endothelin-1 and thromboxane beta-2 in high risky pregnant women [in the first trimester] who are prone to develop preeclampsia. The study population was composed of 80 high risk pregnant women came for their first routine antenatal care visit during the first trimester. The high risk groups chosen for this study included obese pregnant women, chronic hypertensive pregnant women, diabetic pregnant women, those with past history of preeclampsia or eclampsia, primegravida, old pregnant women [above 35 years old] and multiple gestations. The control group consisted of 20 normal pregnant women without any risk factor. Medical history and physical examination were performed for clinical evaluation of all cases. The results indicated that preeclampsia was developed in 35 cases of the total 80 high risk studied pregnant women. There were highly significant differences between the preeclamptic and non preeclamptic study groups in plasma levels of both endothelin-1 and thromboxane beta-2. It was concluded that maternal plasma endothelin-1 and thromboxane beta-2 levels [at the end of the first trimester] may be useful predictors of subsequent development of preeclampsia in high risk group. They may be used as a guide to start preventive measures as low dose aspirin, fish oil administration, antioxidants and calcium supplementation

Variations in white blood count, thromboxane B2 levels and hematocrit in chronic venous hypertension

Objective: To analyze variations in leukocyte count and thromboxane B2 production in the femoral vein of patients with chronic venous hypertension (CVH). Design: Prospective clinical study, controlled, non randomized and open. Location: Hospital das Cl[inicas, Faculdade de Medicina da Universidade de Sao Paulo, referral center, university hospital. Participants: 15 patients with recurring stasis ulcer were analyzed, selected randomly from the venous diseases outpatient center, and 4 without lower limb venous alterations were also analyzed. Intervention: Blood samples from the femoral and brachial veins were drawn following supine and 45º reverse Trendelenburg. Main outcomes measures: Direct leukocyte count and analysis of the thomboxane B2 with enzyme linked immunosorbent assay test. Results: After 30 minutes in reverse Trendelenburg, patients with CVH showed a leukocyte count reduced by +27 per cent (p=0.02) and thromboxane B2 levels increased by +158 per cent (p=0.02). Conclusions: We suggest that future studies of medications for stasis ulcers include their effects on leukocyte entrapment and thromboxane B2 production in the lower limb venous system.

Effect of aspirin treatment on plasma levels of keto PGF 1 alpha and thromboxane B2.

A study was carried out on the effect of aspirin 175 mg/day on the plasma levels of 6 keto PGF 1 alpha and TXB2 in patients with acute myocardial infarction and in patients subjected to coronary artery bypass surgery. Our results showed a fall in the levels of both the prostagladins from day one to day seven and further from seven to day nine in patients with myocardial infarction treated with aspirin 175 mg/day. In patients with myocardial infarction accompanied by arrhythmias the TXB2 levels dominated over the 6 Keto PGF 1 alpha levels. In the group of patients subjected to coronary bypass surgery but after treatment with aspirin 175 mg/day for a period of five days both 6 keto PGF 1 alpha and TXB2 levels fell significantly.

Changes in 6 keto PGF1 alpha and TXB2 in patients with myocardial infarction.

A study was carried out on the plasma levels of 6 Keto PGF1 alpha and Thromboxane B2 (TXB2) in patients with acute myocardial infarction. Our results showed a generalized increase in the levels after acute myocardial infarction. The 6 Keto PGF1 alpha levels increased twice as compared to control values while the TXB2 levels increased nine times as compared to control values. The prostaglandin levels were found to increase from day 1 to day 3 and further from day 3 to day 7. In most of the patients with uncomplicated myocardial infarction the 6 Keto PGF1 alpha levels were higher than the TXB2 levels. In patients with myocardial infarction accompanied by arrhythmias the TXB2 levels dominated over the 6 Keto PGF1 alpha levels.

Thromboxane in complicated and uncomplicated hypertension

This work comprised 77 hypertensive patients as well as 14 healthy normotensive age matched subjects as a control group. They were categorized into uncomplicated hypertension [group I], hypertension complicated by coronary artery disease [group II], and hypertension complicated by acute cerebral infarction [group III]. They were submitted to full clinical assessment, ECG, abdominal sonography, routine laboratory investigations, plasma renin activity, plasma thromboxane B2 and 6-keto-prostaglandin F1 alpha. Echocardiography and CT brain scan were done whenever indicated. 6-keto-prostaglandin F1 alpha level was significantly reduced in group I, while thromboxane B2 level showed no difference, however, the ratio TXB2/6.K.PGF1 alpha was significantly higher when compared with controls. In hypertensive patients complicated by coronary artery disease [group II] while both thromboxane B2 and 6-keto-prostaglandin F1 alpha levels showed no significant difference compared with either controls or group I, the ratio TXB2/6.K.PGF1 was significantly higher. In hypertensive patients complicated by cerebral infarction [group III] both thromboxane B2 level and the ratio TXB2/6.K.PGF1 alpha level were significantly higher when compared with either controls, group I or group II patients. However, 6.K.PGF1 alpha showed no significant difference when compared with these groups. In the three studied groups both TXB2 and 6.K.PGF1 alpha were positively correlated with either systolic, diastolic or mean blood pressure. Also, TXB2 and 6.K.PGF1 alpha levels were positively correlated to each other. In this study, the plasma renin activity showed no significant difference between the controls and any of the three studied groups

Pathogenesis of hypoxemia.

Thrombocytosis and morphological changes in shape and size of circulating platelets are commonly found in splenectomized thalassemia patients. Functional abnormalities of the platelets are evidently related to their fragile nature. Spontaneous aggregation of platelets can easily occur following application of mild pressure either from a stirring magnetic bar or due to centrifugal force. Platelets are hyper-reactive to chemical stimulation and the release of platelet granule contents (eg ATP) together with other membranous lipid metabolites, thromboxane A2 and malondialdehyde is markedly enhanced. The lipid soluble antioxidant, vitamin E is depleted from various blood compartments. The findings suggest that circulating platelets in splenectomized thalassemia are continuously attacked by yet to be identified blood borne factor(s) and the defective platelets could play a pivotal role in the pathogenesis of hypoxemia.