Letizia Galleri

Increased expression of microRNA miR‐326 in type 1 diabetic patients with ongoing islet autoimmunity

The current paradigm that microRNAs represent a new layer of gene regulation has generated much interest in this field. MicroRNAs have emerged as important regulatory factors involved in the developmental processes and in the regulation of insulin secretion and signalling. Furthermore, recent studies revealed an altered microRNA profiling in lymphocytes of patients with autoimmune diseases like multiple sclerosis, in which a hyperexpression of miR‐326 was reported. Here, we analysed the expression levels of miR‐326 in peripheral blood lymphocytes from type 1 diabetic (T1D) patients in relationship with ongoing islet autoimmunity.

Changes of Placental Kiss-1 mRNA Expression and Maternal/Cord Kisspeptin Levels at Preterm Delivery

Kisspeptin, a placental polypeptide secreted throughout pregnancy, is suggested to play a role at parturition. Here we evaluated whether its placental mRNA expression and maternal/fetal plasma levels change at term and preterm delivery, and its effect on oxytocin secretion from placental explants. Samples were collected from 40 women with singleton pregnancies who underwent elective cesarean section at term (TNL), term vaginal delivery (TD), and preterm vaginal delivery (PTD). Plasma Kisspeptin and oxytocin levels were assessed by ELISA; placental mRNA expression by Real-time quantitative RT-PCR analysis. Placental expression was significantly (P < 0.0001) higher in PTD than TNL and TD and significantly (P < 0.001) higher in TD than TNL. Maternal/fetal plasma concentrations did not differ among the groups, and maternal were significantly higher than fetal levels (P < 0.05). In placental explants increasing doses of kisspeptin did not modify oxytocin secretion. In conclusion, labor is associated with increased placental KiSS-1 expression without changes in maternal/fetal circulation.

Activin A, activin receptor type II, nodal, and cripto mRNA are expressed by eutopic and ectopic endometrium in women with ovarian endometriosis.

Activin A is a dimeric protein that regulates endometrial functions by signaling at its receptors, namely type I (ActRI) and type II (ActRII). Nodal is an activin competitor that requires the coreceptor cripto to assemble its signaling pathway through ActRI and ActRII. In the current study, we evaluated the expression of activin A, ActRII, nodal, and cripto in eutopic and ectopic endometrium collected from women with ovarian endometrioma (n = 15) and in eutopic endometrium of healthy participants (n = 15). Eutopic endometrial samples were evaluated according to the stage of menstrual cycle. Total RNA was extracted from tissue homogenates and analyzed by real-time polymerase chain reaction (PCR). Activin A messenger RNA (mRNA) expression in eutopic endometrium of patients with endometriosis was significantly higher than in controls (P < .001) with a 10.2-fold and 7.3-fold increase in the proliferative and secretory phases, respectively. ActRII and nodal mRNA expression were found to be similar in patients with and without endometriosis, while cripto mRNA was markedly lower in eutopic (fold change = 0.03 at proliferative phase, P < .001) and ectopic endometrium (fold change = 0.14, P < .001) of women with endometriosis compared with eutopic endometrium from healthy controls. In conclusion, the altered endometrial expression of activin A and cripto during the menstrual cycle and the differences observed in the endometriotic tissue support the involvement of the activin system in endometrial changes of women with endometriosis.

Low serum and peritoneal fluid concentration of interferon-γ–induced protein-10 (CXCL10) in women with endometriosis

OBJECTIVE To evaluate serum and peritoneal fluid concentrations of interferon-gamma-inducible protein-10 (CXCL10), a chemokine involved in local immune function, in women with endometriosis. DESIGN Prospective study. SETTING Division of Obstetrics and Gynecology, University of Siena. PATIENT(S) A total of 147 women were divided in two groups: women with (n = 77) and without (n = 70) endometriosis. INTERVENTION(S) Serum and peritoneal fluid were collected from all patients undergoing laparoscopy. MAIN OUTCOME MEASURE(S) CXCL10 concentrations were measured by a specific ELISA. RESULT(S) Serum CXCL10 concentrations in women with endometriosis were significantly lower than in those without endometriosis. No statistically significant difference between women with early endometriosis and those with advanced endometriosis was found. CXCL10 concentrations in peritoneal fluid of women with advanced endometriosis were significantly lower than in that of women with an early stage of, or without, endometriosis. CONCLUSION(S) The decreased concentrations of CXCL10 in serum and peritoneal fluid of women with endometriosis indicate an impaired immune activity in women with endometriosis.

Viral Infections and Diabetes

Type 1 diabetes mellitus (T1DM) is a multi-factorial autoimmune disease determined by the interaction of genetic, environmental and immunologic factors. One of the environmental risk factors identified by a series of independent studies is represented by viral infection, with strong evidence showing that viruses can indeed infect pancreatic beta cells with consequent effects ranging from functional damage to cell death. In this chapter we review the data obtained both in man and in experimental animal models in support of the potential participation of viral infections to Type 1 diabetes pathogenesis, with a particular emphasis on virus-triggered islet inflammation, beta-cell dysfunction and autoimmunity.

Evaluation of endometrial activin A secretion for prediction of pregnancy after intrauterine insemination

OBJECTIVE To measure activin A concentrations in uterine washing fluid collected from women with couple infertility undergoing intrauterine insemination (IUI). DESIGN Retrospective case-control study. SETTING Tertiary university center for womens care. PATIENT(S) Fifty women, of whom 25 became pregnant after up to three IUI attempts and 25 did not. INTERVENTION(S) Endocrine and clinical evaluation, semen analyses and hypo-osmotic swelling test, ovarian stimulation, endometrial thickness measurement by ultrasound, uterine washing fluid collection by sonohysterography, and IUI. MAIN OUTCOME MEASURE(S) Activin A measurement by enzyme-linked immunosorbent assay, receiver operating characteristics curve analysis, and pregnancy rates after IUI; sensitivity, specificity, positive and negative likelihood ratios of activin A, and endometrial thickness for pregnancy prediction. RESULT(S) Activin A was measurable in all samples evaluated, and the levels (mean +/- SEM) were statistically significantly higher in the pregnant (0.08 +/- 0.01 ng/mL) than in the nonpregnant (0.022 +/- 0.001 ng/mL) group. Activin A at the cut off of 0.04 ng/mL achieved a sensitivity of 76.0 % (95% CI, 54.9%-90.6%) and a specificity of 100% (95% CI, 86.2%-100%) as a single marker for prediction of pregnancy. CONCLUSION(S) Activin A is secreted into uterine lumen; the levels in endometrial washing fluids were higher in women who subsequently became pregnant after IUI, so its measurement may be useful in predicting successful implantation.

Virus Infections: Lessons from Pancreas Histology

Type 1 diabetes mellitus is a chronic autoimmune disease resulting from the progressive immune-mediated destruction of pancreatic β cells in genetically susceptible individuals, with the likely contribution of environmental factors, among which viruses have been extensively studied. The pathologic hallmark of the disease is insulitis—a process characterized by islet infiltration of immunocompetent cells that has been well characterized in animal models of islet autoimmunity, and to a lesser extent, in humans. Insulitis characterization has provided valuable information to gain insights into the disease pathogenesis. We review the recent literature on the viral contribution to β-cell destruction and dysfunction in type 1 diabetes, with particular reference to the pathology of the pancreatic islet in humans and in animal models of the disease.

Amniotic fluid urocortin, CRF, oestriol, dehydroepiandrosterone sulfate and cortisol concentrations at mid-trimester: putative relationship with preterm delivery

OBJECTIVE Stress-related peptide and steroid hormones are involved in the pathogenesis of preterm delivery, even though their clinical usefulness as predictive markers of preterm delivery remains unclear. The present study evaluated whether mid-trimester amniotic fluid concentrations of stress-related peptides, that is corticothophin-releasing factor (CRF) and urocortin (Ucn) and feto-placental steroids (oestriol, DHEA-S and cortisol) correlated with preterm delivery. STUDY DESIGN It is a retrospective case-control study. Healthy women (n=130) undergoing amniocentesis at mid-gestation for genetic indications, of whom 15 had a preterm delivery (cases) and 115 delivered at term (controls). CRF, urocortin, cortisol, DHEA-S and oestriol concentrations were measured by specific and sensitive immunoenzymatic assays. RESULTS Amniotic fluid urocortin concentrations in the cases (0.50+/-0.07 ng/ml) (M+/-SD) were significantly lower (P<0.0001) than in the control group (0.90+/-0.26 ng/ml), while CRF concentrations did not differ between the cases (1.52+/-0.39 ng/ml) and control group (1.64+/-0.68 ng/ml). Amniotic fluid cortisol (17.71+/-3.72 ng/ml vs. 17.32+/-3.17 ng/ml), DHEA-S (0.16+/-0.06 ng/ml vs. 0.17+/-0.09 ng/ml) and oestriol (4.68+/-1.95 ng/ml vs. 4.79+/-1.84 ng/ml) concentrations were similar in the two groups. CONCLUSIONS The low amniotic fluid concentrations of urocortin at mid-trimester may be a signal of predisposition to preterm delivery, while the unchanged CRF and steroid hormones concentrations in women delivering preterm suggest that this mechanisms are not yet activated at mid-trimester.

Maternal plasma corticotropin-releasing factor (CRF) and CRF-binding protein (CRF-BP) levels in post-term pregnancy: effect of prostaglandin administration.

OBJECTIVE Placental corticotropin-releasing factor (CRF) affects myometrial contractility and the secretion of several uterotonins such as prostaglandins (PGs); however, the activity of CRF is counteracted by CRF-binding protein (CRF-BP). At term and pre-term labor, CRF levels in maternal plasma are highest whereas those of CRF-BP are falling, and the cause of this fall is unknown. Thus, in this study, we investigated the effect of PG administration for labor induction on maternal plasma CRF and CRF-BP concentrations. DESIGN Maternal plasma CRF and CRF-BP levels were assayed before and after (2 h later) induction of labor by intracervical administration of prostaglandin E(2) (PGE(2)), and at delivery in a group of healthy post-term pregnancies (n=18). Controls were women at term out of labor (n=22), who subsequently progressed to deliver a healthy singleton baby. METHODS CRF was measured by two-site immunoradiometric assay, and CRF-BP was assayed by radioimmunoassay. RESULTS Maternal plasma CRF levels were significantly (P<0.0001) lower and CRF-BP significantly (P<0.0005) higher in post-term than in term pregnancies. With respect to induction of labor, 2 mg PGE(2) were sufficient to increase maternal plasma CRF levels at delivery (P<0.005). While 0.5 mg PGE(2) significantly decreased maternal plasma CRF-BP levels at delivery (P<0.001), 2.0 mg PGE(2) significantly reduced CRF-BP concentrations both after 2 h (P<0.05) and at delivery (P<0.0001). CONCLUSIONS In the light of the well-known stimulation of prostaglandin release by CRF, these data suggest a positive feedback effect of PGE(2) on maternal CRF release during induced labor.

Delta-cell-specific expression of hedgehog pathway Ptch1 receptor in murine and human endocrine pancreas

Hedgehog pathway plays an important role during pancreas development, when its inactivation is crucial to assure expression of pancreatic marker genes involved in the organ formation and to assure an appropriate organogenesis. Patched1 (Ptch1) is a transmembrane receptor of hedgehog pathway which has a key role in this process. In fact, heterozygous Ptch1 mutant (ptc+/−) mice are affected by an impaired glucose tolerance accompanied by reduced islet function. In the light that the cell distribution of Ptch1 receptor within the endocrine pancreas has not yet been established, we aimed at identifying the pancreatic endocrine cell subset(s) expressing such molecule.