G. De Sandre

Visceral Fat Accumulation and Its Relation to Plasma Hemostatic Factors in Healthy Men

The associations between abdominal visceral fat and the plasma hemostatic system were examined in 38-year-old healthy men (n=52) with a wide range of fatness and fat distribution. Plasma hemostatic factors and metabolic parameters, including glucose tolerance, were measured, and body fatness and adipose tissue distribution were assessed by using computed tomography. The men with more visceral fat (ie, higher than the median value [n=26]) had a less favorable metabolic profile than the men with less visceral fat (n=26). They also had significantly (P<.05) higher plasma fibrinogen, factor VIII clotting activity, tissue-type plasminogen activator antigen, and plasminogen activator inhibitor-1 (PAI-1) activity (19.2+/-2.4 versus 8.5+/-1.6 AU/mL, P<.001) and lower basal tissue-type plasminogen activator activity. After adjustment for plasma insulin, the men with larger abdominal visceral fat area still had significantly higher plasma PAI-1 activity, but no difference was found in any of the other hemostatic factors. In multiple linear regression analysis, abdominal visceral fat area was a positive predictor of plasma PAI-1 activity, but it failed to show any significant association with other hemostatic factors after controlling for plasma insulin. These results suggest the presence of relationships between abdominal visceral fat and several plasma hemostatic factors that are largely mediated by concomitant alterations in plasma insulin concentration. In addition, our results suggest that abdominal accumulation of visceral fat is an independent predictor of plasma PAI-1 activity.

Expression of plasminogen activator inhibitor-1 in human adipose tissue : a role for TNF-α?

Elevated plasminogen activator inhibitor-1 (PAI-1) plasma levels, responsible for reduced fibrinolysis, are associated with animal and human obesity and with increased cardiovascular disease. The expression of PAI-1 has been found recently in animal and human adipose tissue. Factors and mechanisms regulating such an expression remain to be elucidated. In omental and/or subcutaneous biopsies from obese non-diabetic patients, incubated in Medium 199, we have confirmed that human adipose tissue expresses PAI-1 protein and mRNA; furthermore we have demonstrated that such an expression is clearly evident also in collagenase isolated human adipocytes and that it is stimulated by incubation itself and enhanced by exogenous human tumor necrosis factor-alpha (h-TNF-alpha). Since human adipose tissue produces TNF-alpha, to further characterize the relationship of PAI-1 to TNF-alpha, human fat biopsies were also incubated with Pentoxifylline (PTX) or Genistein, both known to inhibit endogenous TNF-alpha through different mechanisms. PTX caused a dose-dependent decrease of basal PAI-1 protein release, reaching 80% maximal inhibitory effect at 10(-3)M, the same inhibitory effect caused by Genistein at 100 microg/ml. This was associated to a marked inhibition of PAI-1 mRNA and of endogenous TNF-alpha production. Furthermore, when human fat biopsies were incubated in the presence of polyclonal rabbit neutralizing anti-human TNF-alpha antibody (at a concentration able to inhibit 100 UI/ml human TNF-alpha activity), a modest but significant decrease of the incubation induced expression of PAI-1 mRNA was observed (19.8+/-19.0% decrease, P = 0.04, n = 7). In conclusion, the results of this study demonstrate that PAI-I expression is present in human isolated adipocytes and that it is enhanced in human adipose tissue in vitro by exogenous TNF-alpha. Furthermore our data support the possibility of a main role of endogenous TNF-alpha on human adipose tissue PAI-1 expression. This cytokine, produced by human adipose tissue and causing insulin resistance, may be a link in the clinical relationship between insulin-resistance syndrome and increased PAI-1 plasma levels.

Severe impairment of antioxidant system in human hepatoma

Catalase (CAT), glutathione‐peroxidase (GSH‐Px) activity and reduced glutathione content (GSH) were measured in patients who had hepatocellular carcinoma, and values compared with those of normal liver and liver adjacent to neoplastic tissue. The results showed a remarkable reduction of CAT in tumor and corresponding tumor‐free tissue (P < 0.001 and P < 0.02, respectively). All neoplastic samples had a significant lower activity of CAT than the corresponding adjacent tumor‐free tissue (P < 0.05). The GSH‐Px activity of tumor tissue also was lower than normal (P < 0.001) but similar to that of adjacent tissue. No correlation was noted between the two enzyme activities. Glutathione content was extremely low in tumor (P < 0.001) and even in tumor‐free tissue (P < 0.05) when compared with normal liver. In all cases the content of GSH in neoplastic tissue was lower than that of the corresponding tumor‐free tissue (P < 0.05). Whereas in normal liver the activity of GSH‐Px was positively correlated with the content of GSH, in the neoplastic tissue such a relationship disappeared. All these findings suggest that the antioxidant system of hepatocellular carcinoma cell is severely impaired.

The white blood cell count: its relationship to plasma insulin and other cardiovascular risk factors in healthy male individuals

Targher G, Seidell JC, Tonoli M, Muggeo M, De Sandre G, Cigolini M (Division of Endocrinology and Metabolic Diseases, Institute of Clinical Medicine, University of Verona, Italy; and Department of Chronic Diseases and Environmental Epidemiology‐RIVM, Bilthoven, The Netherlands). The white blood cell count: relationship to plasma insulin and other cardiovascular risk factors in healthy males. J Intern Med 1996; 239: 435–41.

Relationships of plasminogen activator inhibitor-1 to anthropometry, serum insulin, triglycerides and adipose tissue fatty acids in healthy men

Increased plasma levels of plasminogen activator inhibitor-1 (PAI-1), responsible for reduced fibrinolytic activity, have been shown to be an important risk factor for cardiovascular disease. PAI-1 plasma levels are influenced by several factors which have not yet been fully clarified, including dietary fat intake. The relationships of PAI-1 with other cardiovascular risk factors are still not well known. In a random sample of 38-year-old healthy men (n = 94), the association of PAI-1 plasma levels (measured as activity and antigen) with anthropometric parameters, serum lipids, fasting and 2 h insulin and glucose concentration after oral glucose-load was analysed. Furthermore, the fatty acid composition of subcutaneous adipose tissue, as an objective and reliable index of dietary fat intake, was measured. The univariate analysis showed that plasma levels of PAI-1 were significantly associated with body mass index (BMI) (r = 0.37, P < 0.001), waist/hip ratio (WHR) (r = 0.26, P < 0.01), serum triglycerides (r = 0.47, P < 0.0001), HDL/total cholesterol ratio (r = -0.35, P < 0.001), fasting and 2-h insulin (r = 0.27, P < 0.01 and r = 0.34, P < 0.001) and glucose concentrations (r = 0.25, P < 0.05 and r = 0.28, P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Early splenectomy and polychemotherapy versus polychemotherapy alone in chronic myeloid leukemia.

Abstract The effect of early splenectomy and of polychemotherapy with hydroxyurea, busulfan, and alternate bimonthly courses of arabinosyl cytosine and vincristine plus prednisone, was evaluated in 139 previously untreated patients with chronic myeloid leukemia (CML), consecutively admitted to 18 hospitals from March 1973 to October 1974. Fifty-six patients were splenectomized and 83 patients were not splenectomized. Splenectomy did not influence the duration of chronic and blastic phase, and did not prolong survival. The prognosis of high risk patients was not improved. During the chronic phase, high platelet counts were more frequent in splenectomy group, and five patients developed thrombotic or thromboembolic complications, 5 to 19 months after the operation. The median survival of the whole group was 50 months, with 32 of 139 patients (actuarial proportion 30%) remaining alive 72 months after diagnosis, but the slope of the survival curve was similar to that of historical controls. The results of this trial suggests that new strategies should be developed for the therapy of CML.

Effects on Red Blood Cell Choline Transport Induced by Different Sulfhydryl Compounds

The uptake of choline was studied in different types of paroxysmal nocturnal hemoglobinuria (PNH)-like RBC obtained from normal human erythrocytes by the action of different sulfhydryl compounds. The results were compared with the uptake of choline in true PNH cells and in normal reticulocytes. The PNH-like cells which better mimicked true PNH were those prepared using acetylcysteine. Indeed these erythrocytes displayed a capacity to incorporate choline against a concentration gradient exactly as PNH cells exposed to either acetylcholine or choline. The uptake of choline by by the other PNH-like cells differed from that of PNH erythrocytes in several ways. The results suggest that every sulfhydryl compound induces a different damage on RBC membrane.