Increased peritoneal and endometrial gene expression of biologically relevant cytokines and growth factors during the menstrual phase in women with endometriosis.

OBJECTIVE: To examine differential messenger RNA (mRNA) expression of relevant cytokines, metalloproteases, growth and adhesion factors in endometrium and peritoneum from women with endometriosis when compared with women without the disease during menstrual and luteal phases of the cycle. DESIGN: Patients with endometriosis were compared with control patients. SETTING: University hospital. PATIENT(S): A total of 35 patients (20 patients during the luteal phase and 15 patients during the menstrual phase) were selected for this study on the basis of cycle phase and presence or absence of endometriosis. INTERVENTION(S): In this study, endometriosis was laparoscopically and histologically confirmed in 24 women with endometriosis of revised American Society for Reproductive Medicine (ASRM) stage I-II (n = 12) and revised ASRM stage III-IV (n = 12), and the presence of a normal pelvis was documented by laparoscopy in 11 control patients. The macroscopically normal peritoneum tissues were collected from lateral wall left or right, near the colon ascendens or descendens. MAIN OUTCOME MEASURE(S): The expression levels were determined as ratios between the target molecules and beta-actin as housekeeping gene. RESULT(S): In women with endometriosis, peritoneal mRNA levels of matrix metalloproteinase (MMP)-3, transforming growth factor-beta, interleukin (IL)-6, and intercellular adhesion molecule-1 and endometrial mRNA levels of MMP-3, tumor necrosis factor (TNF)-alpha, and IL-8 were significantly higher during the menstrual phase when compared with luteal phase. During the menstrual phase of the cycle, both endometrial expression of TNF-alpha, IL-8, and MMP-3 mRNA levels and peritoneal expression of transforming growth factor-beta, IL-6, and intercellular adhesion molecule-1 mRNA levels were significantly higher in women with endometriosis when compared with controls. Immunohistochemical staining confirmed the presence of TNF-alpha in peritoneum and endometrium in both women with endometriosis and controls. CONCLUSION(S): Increased endometrial and peritoneal cytokine mRNA expression during menstruation may contribute to a pelvic inflammatory microenvironment favoring the development of endometriosis.

Early accumulation of interferon-gamma in grafts tolerized by donor-specific blood transfusion: friend or enemy?

BACKGROUND: We previously documented an early (day-2) interferon (IFN)-gamma accumulation in cardiac allografts of rats made tolerant by donor-specific blood transfusion (DSBT) but not in rejecting controls. This contrasted with the IFN-gamma peak seen later (day 5) in rejecting but not in tolerant rats. METHODS: To further examine the role of early intragraft IFN-gamma in DSBT-induced tolerance, we studied whether IFN-gamma up-regulation correlates with the magnitude of the DSBT effect and how IFN-gamma is influenced by interventions abrogating tolerance. RESULTS: The protective effect of DSBT depended upon the timing of administration: day-12 DSBT induced indefinite graft survival; day-6 DSBT gave a moderate, and day-0 DSBT, no graft prolongation. IFN-gamma up-regulation correlated with the DSBT effect: it was maximal after day-12 DSBT, intermediate after day-6 DSBT, and absent after day-0 DSBT. Tolerant splenocytes transferred tolerance into naive rats in a donor-specific manner, indicating that alloantigen-specific regulatory cells operate. Thymectomy prevented regulatory cells development, caused further amplification of intragraft IFN-gamma, and led to rejection, although graft survival was still prolonged. CONCLUSIONS: Day 2 intragraft IFN-gamma correlates with the DSBT protective effect. Thymectomy abrogates DSBT-induced tolerance, prevents regulatory cell development, and paradoxically causes further accumulation of intragraft IFN-gamma. These data indicate that DSBT has a stimulatory and a (thymus-dependent) inhibitory effect on early intragraft IFN-gamma. Intragraft IFN-gamma is beneficial, providing it occurs early and remains moderate. The role of intragraft IFN-gamma in tolerance and rejection depends upon the timing and the degree of production and perhaps the type of IFN-gamma producing cells (regulatory or effector).

Novel alleles of yeast hexokinase PII with distinct effects on catalytic activity and catabolite repression of SUC2.

In the yeast Saccharomyces cerevisiae, glucose or fructose represses the expression of a large number of genes. The phosphorylation of glucose or fructose is catalysed by hexokinase PI (Hxk1), hexokinase PII (Hxk2) and a specific glucokinase (Glk1). The authors have shown previously that either Hxk1 or Hxk2 is sufficient for a rapid, sugar-induced disappearance of catabolite-repressible mRNAs (short-term catabolite repression). Hxk2 is specifically required and sufficient for long-term glucose repression and either Hxk1 or Hxk2 is sufficient for long-term repression by fructose. Mutants lacking the TPS1 gene, which encodes trehalose 6-phosphate synthase, can not grow on glucose or fructose. In this study, suppressor mutations of the growth defect of a tps1delta hxk1delta double mutant on fructose were isolated and identified as novel HXK2 alleles. All six alleles studied have single amino acid substitutions. The mutations affected glucose and fructose phosphorylation to a different extent, indicating that Hxk2 binds glucose and fructose via distinct mechanisms. The mutations conferred different effects on long- and short-term repression. Two of the mutants showed very similar defects in catabolite repression, despite large differences in residual sugar-phosphorylation activity. The data show that the long- and short-term phases of catabolite repression can be dissected using different hexokinase mutations. The lack of correlation between in vitro catalytic hexokinase activity, in vivo sugar phosphate accumulation and the establishment of catabolite repression suggests that the production of sugar phosphate is not the sole role of hexokinase in repression. Using the set of six hxk2 mutants it was shown that there is a good correlation between the glucose-induced cAMP signal and in vivo hexokinase activity. There was no correlation between the cAMP signal and the short- or long-term repression of SUC2, arguing against an involvement of cAMP in either stage of catabolite repression.