Obesity and insulin resistance-related changes in the expression of lipogenic and lipolytic genes in morbidly obese subjects.

BACKGROUND: The storage capacity of adipose tissue may be an important factor linking obesity, insulin resistance (IR), and associated morbidities. The aim of this study was to analyze the expression of lipogenic and lipolytic genes in adipose tissue and the influence of IR. METHODS: We studied the mRNA expression of peroxisome proliferator-activated receptor-γ (PPARγ) and lipogenic and lipolytic enzymes in the visceral (VAT) and subcutaneous adipose tissue (SAT) from 23 morbidly obese patients (MO; 13 with low IR and ten with high IR) and from 15 healthy, lean controls. RESULTS: In the VAT and SAT from the MO, we found an increased expression of PPARγ (p = 0.001 and p = 0.022, respectively), acyl-coenzyme A (CoA)/cholesterol acyltransferase (p < 0.001 and p < 0.001), aquaporin 7 (p < 0.001 and p = 0.003), and adipose triglyceride lipase (p < 0.001 and p < 0.001) and a reduced expression of acetyl-coenzyme A carboxylase (p = 0.004 and p < 0.001), independently of the state of IR. The expression of phosphoenolpyruvate carboxykinase and acyl-CoA synthetase, however, was significantly lower in the MO with high IR (p < 0.05). Glycerol kinase (p = 0.010), hormone-sensitive lipase (p < 0.001), and perilipin (p = 0.006) were only significantly increased in VAT. Acyl-CoA synthetase (p = 0.012) and fatty acid binding protein-4 (p = 0.003) were only significantly decreased in SAT. The expression of the genes studied was only greater in the SAT than the VAT in the controls. CONCLUSION: Our results show an upregulation of genes facilitating triglyceride/fatty acid cycling and a reduction in the genes involved in de novo synthesis of fatty acids in morbid obesity. The expression of some of the genes studied seems to be related with the state of IR. VAT and SAT differ metabolically and also between controls and MO.

[Immunity related to cytomegalovirus after allogenic bone marrow transplantation: role of donor immunity to cytomegalovirus in the incidence of cytomegalovirus infection in recipients]. / Immunité vis-à-vis du cytomégalovirus après greffe de moelle osseuse allogénique: Rôle de l'immunité du donneur vis-à-vis du cytomégalovirus dans l'incidence de l'infection à cytomégalovirus chez les receveurs.

Cytomegalovirus infections are severe and frequent after BMT. This study included 34 bone marrow transplant recipients (23 aplastic anaemias and 11 leukaemias), their marrow donors and 125 related or non related normal controls. Assays were performed before transplantation and every 30 days between D 0 and D 90, and then every six months. They included detection of CMV induced lymphocyte proliferation in vitro, CMV antibody determinations by complement fixation and reverse haemagglutination, viraemia and/or viruria. Similarly, cellular immunity to mitogens and to other specific antigens was evaluated. During the period of study, 22 patients developed CMV infection. The diagnostic was confirmed by virus isolation from the 12th to the 96th day after the graft. Development of positive CMV proliferation test occurred from the 9th to the 84th day after virus isolation (30 to 120th day after the graft). In one case, the CMV infection was only proved by the lymphocyte proliferation to CMV in vitro and only 60 days later by viruria and 105 days later by detection of CMV antibodies. For the other 12 patients (7 aplasies and 5 leukaemias) and 10 of their bone marrow donors, no CMV infection was proved, before or after transplant, by any of the assays performed. By selecting a donor without previous CMV infection, we hope to reduce the incidence of CM infection in recipients.