PIVL,a new serine protease inhibitor from Macrovipera lebetina transmediterranea venom,impairs motility of human glioblastoma cells

A novel Kunitz-type serine proteinase inhibitor, termed PIVL, was purified to homogeneity from the venom of the Tunisian snake Macrovipera lebetina transmediterranea. It is a monomeric polypeptide chain cross-linked by three disulfide linkages with an isotope-averaged molecular mass of 7691.7 Da. The 67-residue full-length PIVL sequence was deduced from a venom gland cDNA clone. Structurally, PIVL is built by a single Kunitz/BPTI-like domain. Functionally, it is able to specifically inhibit trypsin activity. Interestingly, PIVL exhibits an anti-tumor effect and displays integrin inhibitory activity without being cytotoxic. Here we show that PIVL is able to dose-dependently inhibit the adhesion, migration and invasion of human glioblastoma U87 cells. Our results also show that PIVL impairs the function of αvβ3 and to a lesser extent, the activity of αvβ6, αvβ5, α1β1 and α5β1 integrins. Interestingly, we demonstrate that the ⁴¹RGN⁴³ motif of PIVL is likely responsible for its anti-cancer effect. By using time lapse videomicroscopy, we found that PIVL significantly reduced U87 cells motility and affected cell directionality persistence by 68%. These findings reveal novel pharmacological effects for a Kunitz-type serine proteinase inhibitor.     

Chromosomal evaluation in a group of Tunisian patients with non-obstructive azoospermia and severe oligozoospermia attending a Tunisian cytogenetic department

Male infertility is the cause in half of all childless partnerships. Numerous factors contribute to male infertility, including chromosomal aberrations and gene defects. Few data exist regarding the association of these chromosomal aberrations with male infertility in Arab and North African populations. We therefore aimed to evaluate the frequency of chromosomal aberrations in a sample of 476 infertile men with non-obstructive azoospermia (n = 328) or severe oligozoospermia (n = 148) referred for routine cytogenetic analysis to the department of cytogenetics of the Pasteur Institute of Tunis. The overall incidence of chromosomal abnormalities was about 10.9%. Out of the 52 patients with abnormal cytogenetic findings, sex chromosome abnormalities were observed in 42 (80.7%) including Klinefelter syndrome in 37 (71%). Structural chromosome abnormalities involving autosomes (19.2%) and sex chromosomes were detected in 11 infertile men. Abnormal findings were more prevalent in the azoospermia group (14.02%) than in the severe oligozoospermia group (4.05%). The high frequency of chromosomal alterations in our series highlights the need for efficient genetic testing in infertile men, as results may help to determine the prognosis, as well as the choice of an assisted reproduction technique. Moreover, a genetic investigation could minimize the risk of transmitting genetic abnormalities to future generations.     

Mutational spectrum of Xeroderma pigmentosum group A in Egyptian patients

Xeroderma pigmentosum (XP) is a rare autosomal recessive hereditary disease characterized by hyperphotosensitivity, DNA repair defects and a predisposition to skin cancers. The most frequently occurring type worldwide is the XP group A (XPA). There is a close relationship between the clinical features that ranged from severe to mild form and the mutational site in XPA gene. The aim of this study is to carry out the mutational analysis in Egyptian patients with XP-A. This study was carried out on four unrelated Egyptian XP-A families. Clinical features were examined and direct sequencing of the coding region of XPA gene was performed in patients and their parents. Direct sequencing of the whole coding region of the XPA gene revealed the identification of two homozygous nonsense mutations: (c.553C>T; p.(Gln185*)) and (c.331G>T; p.(Glu111*)), which create premature, stop codon and a homodeletion (c.374delC: p.Thr125Ilefs*15) that leads to frameshift and premature translation termination. We report the identification of one novel XPA gene mutation and two known mutations in four unrelated Egyptian families with Xermoderma pigmentosum. All explored patients presented severe neurological abnormalities and have mutations located in the DNA binding domain. This report gives insight on the mutation spectrum of XP-A in Egypt. This would provide a valuable tool for early diagnosis of this severe disease.     

Long-Term Physiological Alterations and Recovery in a Mouse Model of Separation Associated with Time-Restricted Feeding: A Tool to Study Anorexia Nervosa Related Consequences

Background

Anorexia nervosa is a primary psychiatric disorder, with non-negligible rates of mortality and morbidity. Some of the related alterations could participate in a vicious cycle limiting the recovery. Animal models mimicking various physiological alterations related to anorexia nervosa are necessary to provide better strategies of treatment.

Aim

To explore physiological alterations and recovery in a long-term mouse model mimicking numerous consequences of severe anorexia nervosa.

Methods

C57Bl/6 female mice were submitted to a separation-based anorexia protocol combining separation and time-restricted feeding for 10 weeks. Thereafter, mice were housed in standard conditions for 10 weeks. Body weight, food intake, body composition, plasma levels of leptin, adiponectin, IGF-1, blood levels of GH, reproductive function and glucose tolerance were followed. Gene expression of several markers of lipid and energy metabolism was assayed in adipose tissues.

Results

Mimicking what is observed in anorexia nervosa patients, and despite a food intake close to that of control mice, separation-based anorexia mice displayed marked alterations in body weight, fat mass, lean mass, bone mass acquisition, reproductive function, GH/IGF-1 axis, and leptinemia. mRNA levels of markers of lipogenesis, lipolysis, and the brown-like adipocyte lineage in subcutaneous adipose tissue were also changed. All these alterations were corrected during the recovery phase, except for the hypoleptinemia that persisted despite the full recovery of fat mass.

Conclusion

This study strongly supports the separation-based anorexia protocol as a valuable model of long-term negative energy balance state that closely mimics various symptoms observed in anorexia nervosa, including metabolic adaptations. Interestingly, during a recovery phase, mice showed a high capacity to normalize these parameters with the exception of plasma leptin levels. It will be interesting therefore to explore further the central and peripheral effects of the uncorrected hypoleptinemia during recovery from separation-based anorexia.     

Physiological and biochemical effects of Olea europaea leaf extracts from four phenological growth stages on the oogenesis of female locust Locusta migratoria

The effects of olive leaf extract (OLE) are studied on several reproductive variables and the ovarian biochemical composition of Locusta migratoria (Orthoptera: Acrididae) adult females. The methanolic extracts are prepared from the leaves sampled during four phenological growth stages of olive tree: cluster formation (Cf), swelling inflorescence buds (Sib), full flowering (Ff) and endocarp hardening (Eh). When applied to adult females during the pre‐ovipositional phase, the treatment elicites a significant adverse effect on their reproductive potential. Indeed, OLE significantly reduces both fecundity and fertility and affects oocyte growth during the first gonadotrophic cycle, as indicated by measurements of ovarian weight, length of terminal oocytes and ovarian index. Furthermore, OLE is examined with respect to ovarian biochemical components. Biochemical analyses reveal a significant reduction of ovarian contents of proteins, lipids and carbohydrates, suggesting a disruption in the incorporation of the haemolymph metabolites in the oocytes and an interference of OLE with the vitellogenesis process. The antigonadotrophic effect is confirmed by a histological study of the ovaries, which clearly shows a delay in ovarian development and in yolk accumulation in the basal oocytes of treated females. The most effect is noted with the extract prepared from the leaves collected at the swelling inflorescence buds for all measured parameters, which appears to be related to its high content of polyphenols.