Localization and distribution of wolframin in human female reproductive tract

Wolframin, a transmembrane glycoprotein of endoplasmic reticulum consisting of 890 amino acids, is encoded by the WFS1 gene, mutated in the Wolfram syndrome. This pathology, also called DIDMOAD, is an autosomal recessive disorder defined by the association of diabetes mellitus, optic atrophy, and further organ abnormalities. To gain further insight into the pathogenesis of diseases associated with WFS1 mutations, we conducted an immunohistochemical study to investigate its pattern of expression in human female reproductive tract in physiologic and pathologic conditions. For this purpose, samples of physiologic and pathologic endometrium, samples of placenta throughout pregnancy in normal and diabetic pregnant women, were used. In physiologic endometrium, we observed a light increase of wolframin from proliferative to secretory phase where wolframin was localized in the glands, stroma and cells lining blood vessels. In menopause, wolframin expression increased with a glandular and stromal localization. In pathologic endometrium, we observed an increase of wolframin expression from hyperplasia to polyps until a higher expression in carcinoma tissues. In normal placenta there was a modulation of wolframin throughout pregnancy with a strong level of expression during the first trimester and a moderate level in the third trimester. In diabetic women, the wolframin expression was strongly reduced in the third trimester of gestation. In human endometrium, wolframin seems to have a role in differentiation program. Deregulation of these functions may induce the onset of several endometrial pathologies. Moreover, in normal placenta wolframin may be required to sustain normal rates of cytotrophoblast cell proliferation during the first trimester of gestation. The decrease of wolframin expression in diabetic placentae may hypothesize that this protein is directly regulated by insulin concentration also in the placenta, suggesting that this protein physiologically maintain the glucose homeostasis in this organ

Identification of protein-protein interactions of human HtrA1.

The human heat shock protein HtrA1, a member of the HtrA family of serine proteases, is a evolutionarily highly conserved factor which displays a widespread pattern of expression. The yeast two-hybrid technique was employed to identify new cellular proteins physically interacting with HtrA1, and thus potential targets of this serine protease. An enzymatically inactive HtrA1 point mutant, HtrA1-S328A, was generated and used as bait in a yeast two-hybrid system. Fifty-two plasmids were isolated from primary positive yeast clones. Subsequent sequencing and BLAST analysis revealed cDNAs encoding for 13 different proteins. These putative binding partners of HtrA1 appeared to be a) components of extracellular matrix; b) factors related to signal pathways, and c) unknown proteins. Among the 13 positive clones identified and reported here, it is worth of note that the interaction of HtrA1 with tubulin and collagen (extracellular matrix proteins) and with tuberin (cytoplasmic protein) is confirmed by other studies, and this further supports previous findings in which HtrA1 can be found active as an intracytoplasmic protein or as secreted protein as well

Role of FAP48 in HIV-associated lipodystrophy

The introduction of highly active antiretroviral therapies (HAART) has significantly changed the clinical course of HIV disease, with prolonged survival and better quality of life for HIV infected patients. However, this successful therapeutic advance has been partially marked by the development of serious long-term side effects including metabolic alterations, cardiovascular disease, kidney impairment, bone alterations and adipose tissue redistribution. This last phenomenon is currently indicated as HIV related lipodystrophy (Barbaro, 2006). Even if some studies suggested an independent role for HIV in the development of lipodystrophic phenotype, there is a widely accepted consensus that the risk to develop fat redistribution in HIV patients has to be mostly related to antiretroviral therapy. In order to investigate new pathways involved in the development of lipodystrophy, our group performed an array screening using two identical filter arrays with cDNAlabeled probes, generated from the adipose tissue of either HIV patients affected or not affected by lipodystrophy. Among the genes selected, we focused our attention on a recently described 48 kDa protein of 417 amino acids named FAP48. Our results suggest, using 3T3-L1-FAP48 stable clone, that FAP48 over-expression results in rapid NFAT dephosphorilatyon by activating CaN and in the increase of aP2 gene transcription, a gene expressed at the last phase of the adipocyte differentiation. These data support the role of Fap48 in the activation of adipocyte differentiation through a pathway involving NFAT. Moreover we evaluated the expression of PPARγ and aP2 in 3T3-L1 FAP48pcDNA stably transfected cells treated with five antiretroviral drugs (Indinavir, Amprenavir, Efavirenz, Stavudine and Saquinavir), belonging to the three main classes of anti-HIV drugs, that were able, in our experimental model, to affect adipocyte differentiation (Esposito et al., 2009). We observed that cells treated with Saquinavir and Efavirenz, using 3T3-L1- FAP48 stable clone, are characterized by an increased expression of PPARγ and aP2, during the 6 day time course, compared with the control cells. This evidence supports the hypothesis of a protective mechanism, that in 3T3L1 cells could counteract the toxicity of Efavirenz and Saquinavir or could be activated in presence of these drugs. Drawing from our experimental results it can be then postulated that this mechanism could work trough FAP48/ FBP52/Hsp90 pathway, suggesting this complex as a potential target for novel therapeutic approaches to the HAART related lipodystrophy in patients treated with regimen including Efavirenz and Saquinavir

Selective class II HDAC inhibitors impair myogenesis by modulating the stability and activity of HDAC-MEF2 complexes.

International audienceHistone deacetylase (HDAC) inhibitors are promising new epi-drugs, but the presence of both class I and class II enzymes in HDAC complexes precludes a detailed elucidation of the individual HDAC functions. By using the class II-specific HDAC inhibitor MC1568, we separated class I- and class II-dependent effects and defined the roles of class II enzymes in muscle differentiation in cultured cells and in vivo. MC1568 arrests myogenesis by (i) decreasing myocyte enhancer factor 2D (MEF2D) expression, (ii) by stabilizing the HDAC4-HDAC3-MEF2D complex, and (iii) paradoxically, by inhibiting differentiation-induced MEF2D acetylation. In vivo MC1568 shows an apparent tissue-selective HDAC inhibition. In skeletal muscle and heart, MC1568 inhibits the activity of HDAC4 and HDAC5 without affecting HDAC3 activity, thereby leaving MEF2-HDAC complexes in a repressed state. Our results suggest that HDAC class II-selective inhibitors might have a therapeutic potential for the treatment of muscle and heart diseases

Nuovi siti di allevamento per la vongola R. philippinarum in laguna di Venezia: approccio (eco)tossicologico.

Objective: There is increasing concern about the appropriateness of prescribing pharmaceutical opioids for chronic non-cancer pain (CNCP), given the risks of problematic use and dependence. This article examines pharmaceutical opioid dose and dependence and examines the correlates of each. Design: Baseline data were obtained from a national sample of 1,424 people across Australia (median 58 years, 55% female and experiencing pain for a median of 10 years), who had been prescribed opioids for CNCP. Current opioid consumption was estimated in oral morphine equivalent (OME; mg per day), and ICD-10 pharmaceutical opioid dependence was assessed using the Composite International Diagnostic Interview. Results: Current opioid consumption varied widely: 8.8% were taking = 200 mg OME. Greater daily OME consumption was associated with higher odds of multiple physical and mental health issues, aberrant opioid use, problems associated with opioid medication and opioid dependence. A significant minority, 8.5%, met criteria for lifetime ICD-10 pharmaceutical opioid dependence and 4.7% met criteria for past year ICD-10 pharmaceutical opioid dependence. Multivariate analysis found past-year dependence was independently associated with being younger, exhibiting more aberrant behaviors and having a history of benzodiazepine dependence. Conclusions: In this population of people taking opioids for CNCP, consumption of higher doses was associated with increased risk of problematic behaviors, and was more likely among people with a complex profile of physical and mental health problems

The serine protease HtrA1 specifically interacts and degrades the tuberous sclerosis complex 2 protein

Hamartin and tuberin are products of the tumor suppressor genes TSC1 and TSC2, respectively. Mutations affecting either gene result in the tuberous sclerosis syndrome, a neurologic genetic disorder characterized by the formation of multiple benign tumors or hamartomas. In this study, we report the identification of TSC2, but not TSC1, as a substrate of HtrA1, a member of the human HtrA family proteins of serine proteases. We show the direct interaction and colocalization in the cytoplasm of HtrA1 and TSC2 and that HtrA1 cleaves TSC2 both in vitro and in vivo. Finally, we show that alterations in HtrA1 expression cause modifications in phosphorylation status of two downstream targets of TSC2: 4E-BP1 and S6K. Our data suggest that, under particular physiologic or pathologic conditions, HtrA1 degrades TSC2 and activates the downstream targets. Considering that HtrA1 levels are significantly increased during embryogenesis, we speculate that one of the targets of HtrA1 activity during fetal development is the TSC2-TSC1 pathway