Proteomic analysis of cerebrospinal fluid from obese women with idiopathic intracranial hypertension: a new approach for identifying new candidates in the pathogenesis of obesity.

Body weight control is tightly regulated in the hypothalamus. The inaccessibility of human brain tissue can be partially solved by using cerebrospinal fluid (CSF) as a tool for assessing the central nervous system's production of orexigen and anorexigen factors. Using proteomic analysis, the present study investigated the differentially displayed proteins in human CSF from obese and non-obese subjects. We designed a case-control study conducted in a reference hospital where eight obese (cases) and eight non-obese (controls) women with idiopathic intracranial hypertension were included. Intracranial hypertension was normalised through the placement of a ventriculo- or lumboperitoneal shunt in the 12 months before their inclusion in the study. Isotope-coded protein label (for proteins > 10 kDa) and label-free liquid chromatography (for proteins < 10 kDa) associated with mass spectrometry analysis were used. Eighteen differentially expressed proteins were identified. Many of them fall into three main groups: inflammation (osteopontin, fibrinogen γ and ß chain, α1 acid glycoprotein 2 and haptoglobin), neuroendocrine mediators (neurosecretory protein VGF, neuroendocrine protein 7B2, chromogranin-A and chromogranin B), and brain plasticity (testican-1, isoform 10 of fibronectin, galectin-3 binding protein and metalloproteinase inhibitor type 2). The differential production of osteopontin, neurosecretory protein VGF, chromogranin-A and fibrinogen γ chain was further confirmed by either enzyme-linked immunosorbent assay or western blotting. In conclusion, we have identified potential candidates that could be involved in the pathogenesis of obesity. Further studies aiming to investigating the precise role of these proteins in the pathogenesis of obesity and their potential therapeutic implications are needed.

Proteomic analysis of human vitreous fluid by fluorescence-based difference gel electrophoresis (DIGE): a new strategy for identifying potential candidates in the pathogenesis of proliferative diabetic retinopathy.

AIMS/HYPOTHESIS: The aim of this study was to compare the protein profile of vitreous fluid from diabetic patients with proliferative diabetic retinopathy (PDR) with that from non-diabetic patients with idiopathic macular holes (MH). The mRNA of proteins differentially produced was also assessed in the retinas from diabetic and non-diabetic donors. MATERIALS AND METHODS: Vitreous humour from type 1 diabetic patients with PDR (n = 8) and from non-diabetic patients with MH (n = 10) closely matched in terms of age were studied. The comparative proteomic analysis was performed using fluorescence-based difference gel electrophoresis (DIGE). Differentially produced proteins (abundance ratio >1.4, p < 0.05) were identified by mass spectrometry. Expressions of mRNA were measured by real-time RT-PCR in retinas from ten human eyes obtained at post-mortem (five eyes from diabetic subjects and five eyes from non-diabetic subjects). RESULTS: Eight proteins were highly produced in PDR patients in comparison with non-diabetic subjects: zinc-alpha(2)-glycoprotein (ZAG), apolipoprotein (apo) A1, apoH, fibrinogen A, and the complement factors C3, C4b, C9 and factor B). We found three proteins that were underproduced in PDR subjects: pigment epithelial derived factor (PEDF), interstitial retinol-binding protein (IRBP) and inter-alpha-trypsin inhibitor heavy chain (ITIH2). There was no overlap in the vitreous levels of the above-mentioned proteins between PDR patients and non-diabetic control subjects. The differential production of ZAG, C3, factor B, PEDF and IRBP was further confirmed by western blot, and was in agreement with mRNA levels detected in the retina. CONCLUSIONS/INTERPRETATION: Proteomic analysis by DIGE, which permits an accurate quantitative comparison, was useful in identifying new potential candidates involved in the pathogenesis of PDR.

[Breast feeding and birth of twins]. / Lactancia materna y parto gemelar.

OBJECTIVES: To investigate the breast-feeding (BF) situation after birth of twins and find what factors affect the decision to breast-feed, its length and the reasons for stopping it. DESIGN: Retrospective, observational study. SETTING: Sabadell Hospital, Barcelona. PARTICIPANTS: All the women who gave birth to twins between January 1994 and June 1997 (n = 72). MAIN RESULTS: 64 women (88.9%) began BF. It was exclusive in 37 cases (57.8%) and mixed in the other 27 (42.2%). The main reason for choice was "better feeding" (100% of cases). The age of mothers, the type of birth, the weight of the children, admissions to the New-born Baby Department, work situation, mother's educational qualifications and the existence of domestic help affected neither initial breast-feeding nor its length. Women with prior counselling started BF in greater numbers than those not counselled (p = 0.026). Almost half of them received the information through the matron or nurse. Mean length of BF was 102 days. After two months, half of those who began BF were still breast-feeding; and at four months, 26.5%. CONCLUSIONS: We observed a high level of starting breast-feeding after twin births, almost the same as for single births. Women with previous knowledge of the question are more likely to breast-feed. The length of BF is slightly greater in the studies reviewed. Adequate prenatal, postnatal and puerperal support from health-workers can have a positive effect on the success of BF after twin births.