Differentiation of Adipose Tissue Mesenchymal Stem Cells into Endothelial Cells Depends on Fat Depot Conditions: Regulation by miRNA.

The development of obesity is associated with substantial modulation of adipose tissue (AT) structure. The plasticity of the AT is reflected by its remarkable ability to expand or reduce in size throughout the adult lifespan, which is linked to the development of its vasculature. This increase in AT vasculature could be mediated by the differentiation of adipose tissue-derived stem cells (ASCs) into endothelial cells (ECs) and form new microvasculature. We have already shown that microRNA (miRNA)-145 regulates the differentiation of ASCs into EC-like (ECL) cells. Here, we investigated whether ASCs-differentiation into ECs is governed by a miRNAs signature that depends on fat depot location and /or the metabolic condition produced by obesity. Human ASCs, which were obtained from white AT by surgical procedures from lean and obese patients, were induced to differentiate into ECL cells. We have identified that miRNA-29b-3p in both subcutaneous (s)ASCs and visceral ASCs and miRNA-424-5p and miRNA-378a-3p in subcutaneous (s)ASCs are involved in differentiation into EC-like cells. These miRNAs modulate their pro-angiogenic effects on ASCs by targeting FGFR1, NRP2, MAPK1, and TGF-ß2, and the MAPK signaling pathway. We show for the first time that miRNA-29b-3p upregulation contributes to ASCs' differentiation into ECL cells by directly targeting TGFB2 in both sASCs and visceral ASCs. Moreover, our results reveal that, independent of sASCs' origin (obese/lean), the upregulation of miRNA-378a-3p and the downregulation of miRNA-424-5p inhibit MAPK1 and overexpress FGFR1 and NRP2, respectively. In summary, both the adipose depot location and obesity affect the differentiation of resident ASCs through the expression of specific miRNAs.

Type 2 Diabetes in Obesity: A Systems Biology Study on Serum and Adipose Tissue Proteomic Profiles.

Obesity is associated with metabolic disorders such as insulin resistance and type 2 diabetes mellitus (T2DM), further increasing an already heightened cardiovascular risk. Here, amongst obese class III bariatric surgery patients, we have investigated the effect of T2DM in serum and in two, same patient, adipose tissue (AT) depots through proteomic profile expression analyses. Serum and AT samples from subcutaneous (SAT) and visceral (VAT) fat were collected during bariatric surgery. Bead-based targeted multiplex assay systems were used to simultaneously detect and quantify multiple targets in serum samples (targeted proteomics) and analyze changes in adipokine serum composition. AT samples were assessed through an untargeted proteomics approach. Through a systems biology analysis of the proteomic data, information on the affected biological pathways was acquired. In obese class III individuals, the presence of T2DM induced a significantly higher systemic release of ghrelin, GLP-1, glucagon, MMP3, BAFF, chitinase 3-like 1, TNF-R1 and TNF-R2, and a lower systemic release of IL-8. SAT and VAT proteomes belonging to the same patient showed significant differences in local protein content. While the proteins upregulated in VAT were indicative of metabolic dysregulation, SAT protein upregulation suggested adequate endocrine regulation. The presence of T2DM significantly affected VAT protein composition through the upregulation of dysregulating metabolic pathways, but SAT protein composition was not significantly modified. Our results show that T2DM induces metabolic dysregulation in obese individuals with changes in systemic marker levels and impairment of proteostasis in VAT but not in SAT.

Eeyarestatin I, an inhibitor of the valosin-containing protein, exhibits potent virucidal activity against the flaviviruses.

Cellular responses to stress generally lead to the activation of the endoplasmic reticulum-associated protein degradation (ERAD) pathway. Several lines of study support that ERAD may be playing a proviral role during flaviviral infection. A key host factor in ERAD is the valosin-containing protein (VCP), an ATPase which ushers ubiquitin-tagged proteins to degradation by the proteasome. VCP exhibits different proviral activities, such as engaging in the biogenesis of viral replication organelles and facilitating flavivirus genome uncoating after the viral particle entry. To investigate the possible antiviral value of drugs targeting VCP, we tested two inhibitors: eeyarestatin I (EEY) and xanthohumol (XAN). Both compounds were highly effective in suppressing Zika virus (ZIKV) and Usutu virus (USUV) replication during infection in cell culture. Further analysis revealed an unexpected virucidal activity for EEY, but not for XAN. Preincubation of ZIKV or USUV with EEY before inoculation to cells resulted in significant decreases in infectivity in a dose- and time-dependent manner. Viral genomes in samples previously treated with EEY were more sensitive to propidium monoazide, an intercalating agent, with 10- to 100-fold decreases observed in viral RNA levels, supporting that EEY affects viral particle integrity. Altogether, these results support that EEY is a strong virucide against two unrelated flaviviruses, encouraging further studies to investigate its potential use as a broad-acting drug or the development of improved derivatives in the treatment of flaviviral infection.

Cardiovascular Risk Factors and Differential Transcriptomic Profile of the Subcutaneous and Visceral Adipose Tissue and Their Resident Stem Cells.

BACKGROUND: The increase in the incidence of obesity and obesity-related cardiovascular risk factors (CVRFs) over the last decades has brought attention on adipose tissue (AT) pathobiology. The expansion of AT is associated with the development of new vasculature needed to perfuse the tissue; however, not all fat depots have the same ability to induce angiogenesis that requires recruitment of their own endothelial cells. In this study we have investigated the effect of different CVRFs, on the angiogenic capacity of the subcutaneous (SAT) and visceral (VAT) adipose tissue and on the function of their mesenchymal cell reservoir. METHODS: A transcriptomic approach was used to compare the different angiogenic and inflammatory profiles of the subcutaneous and visceral fat depots from individuals with obesity, as well as their resident stem cells (ASCs). Influence of other risk factors on fat composition was also measured. Finally, the microvesicles (MVs) released by ASCs were isolated and their regenerative potential analyzed by molecular and cellular methodologies. RESULTS: Obesity decreases the angiogenic capacity of AT. There are differences between SAT and VAT; from the 21 angiogenic-related genes analyzed, only three were decreased in SAT compared with those decreased in VAT. ASCs isolated from both fat depots showed significant differences; there was a significant up-regulation of the VEGF-pathway on visceral derived ASCs. ASCs release MVs that stimulate endothelial cell migration and angiogenic capacity. CONCLUSIONS: In patients with obesity, SAT expresses a greater number of angiogenic molecules than VAT, independent of the presence of other CVRFs.

Pancreatic endocrine tumors or apudomas.

INTRODUCTION AND OBJECTIVE: pancreatic endocrine tumors (PET) are difficult to diagnose. Their accurate localization using imaging techniques is intended to provide a definite cure. The goal of this retrospective study was to review a PET series from a private institution. PATIENTS AND METHODS: the medical records of 19 patients with PETs were reviewed, including 4 cases of MEN-1, for a period of 17 years (1994-2010). A database was set up with ten parameters: age, sex, symptoms, imaging techniques, size and location in the pancreas, metastasis, surgery, complications, adjuvant therapies, definite diagnosis, and survival or death. RESULTS: a total of 19 cases were analyzed. Mean age at presentation was 51 years (range: 26-67 y) (14 males, 5 females), and tumor size was 5 to 80 mm (X: 20 mm). Metastatic disease was present in 37% (7/19). Most underwent the following imaging techniques: ultrasounds, computed tomography (CT) an magnetic resonance imaging (MRI). Fine needle aspiration punction (FNA) was performed for the primary tumor in 4 cases. Non-functioning: 7 cases (37%), insulinoma: 2 cases [1 with possible multiple endocrine neoplasia (MEN)], Zollinger-Ellison syndrome (ZES) from gastrinoma: 5 (3 with MEN-1), glucagonoma: 2 cases, 2 somatostatinomas; carcinoid: 1 case with carcinoide-like syndrome. Most patients were operated upon: 14/19 (73%). Four (4/14:28%) has postoperative complications following pancreatectomy: pancreatitis, pseudocyst, and abdominal collections. Some patients received chemotherapy (4), somatostatin (3) and interferon (2) before or after surgery. Median follow-up was 48 months. Actuarial survival during the study was 73.6% (14/19). CONCLUSIONS: age was similar to that described in the literature. Males were predominant. Most cases were non-functioning (37%). Most patients underwent surgery (73%) with little morbidity (28%) and an actuarial survival of 73.6% at the time of the study.

Endoscopic dilation of gastrojejunal anastomotic strictures after laparoscopic gastric bypass. Predictors of initial failure.

BACKGROUND AND AIMS: Laparoscopic Roux-en-Y gastric bypass (LRYGB) is the most frequent technique performed in bariatric surgery. Gastrojejunal anastomotic stricture is one of the most common postoperative complications. The aims of this study were to evaluate the efficacy and safety of endoscopic balloon dilation in the treatment of the gastrojejunal anastomotic strictures after LRYGB and to look for predicting factors that would indicate the need of repeated dilations. METHODS: We included all patients with morbid obesity who underwent a LRYGB at our institution between January 2002 and July 2007. All patients who developed symptoms compatible with stricture of the gastrojejunostomy were referred to upper gastrointestinal endoscopy and underwent endoscopic balloon dilation. RESULTS: One hundred and five out of the 1,330 patients (7.8%) developed an anastomotic stricture. The mean time to diagnosis was 3 months after the surgery. The mean diameter of the stricture was 5 mm. Sixty out of the 105 patients required only one dilation (57%), 29 required two dilations (27,6%), 13 required three dilations, and 3 patients underwent a fourth dilation. Clinical success was achieved in 100% of the cases, with an average of 1.6 dilations. The statistical analysis showed that only the time from surgery to stricture formation (p = 0.007) and the diameter achieved at the first dilation (p = 0.015) had statistical significance as predictors of the need of one or more dilations. CONCLUSIONS: Endoscopic balloon dilation is a safe and effective method. Most of the patients are successfully managed with one or two dilations. The longer time from surgery to the appearance of symptoms ant the largest diameter achieved at the first dilation are the only predicting factors of success with only one dilation.

Management of anastomotic leaks after laparoscopic Roux-en-Y gastric bypass.

BACKGROUND: Anastomotic leaks after bariatric surgery carry high morbidity and mortality. We aimed to describe our experience of the diagnosis and management of gastrointestinal anastomotic leaks in patients undergoing laparoscopic gastric bypass in a single institution. METHODS: Of 1,200 patients who underwent laparoscopic Roux-en-Y gastric bypass with manual gastrojejunal anastomosis for morbid obesity from January 2002 to January 2007, we retrospectively analyzed 59 patients with anastomotic leak. The location of the leak, day of diagnosis, diagnostic methods, clinical manifestations, treatment modalities, associated complications, and length of hospital stay were analyzed. RESULTS: Leaks were located as follows: 67.8% in the gastrojejunostomy, 10.2% in the gastric pouch, 3.4% in the excluded stomach, 5.1% in the jejunojejunal anastomosis, 3.4% in the gastrojejunostomy plus pouch, 3.4% in the pouch plus excluded stomach, and 6.8% in undetermined sites. Routine upper gastrointestinal series revealed contrast extravasation in nine patients (15.3%). Leaks were asymptomatic at diagnosis in 29 patients (49.2%). Surgical reintervention was carried out in 23 patients, and conservative treatment was provided in the remaining 36. Transfer to the intensive care unit was required in 11 patients, with five deaths (0.4%). CONCLUSION: In our experience, most anastomotic leaks can be managed with conservative measures alone. In many patients, abdominal drains are effective in the management of leaks, obviating the need for reintervention. Nasoenteral nutrition was effective in the non-operative management of gastrojejunal leaks in patients without signs of systemic toxicity.

New oral findings in Cohen syndrome.

Cohen syndrome is a hereditary disorder transmitted as an autosomal-recessive trait. Approximately 100 cases have been reported in the genetic and pediatric literature. Despite the fact that oral alterations are often observed in these cases, only 1 work has been published addressing this specific topic, and it tended to concentrate on periodontal abnormalities. The present study details 2 new patients, 2 brothers (8 and 11 years old), and mainly consists of an analysis of the dentomaxillary anomalies that until now have not been studied in depth. In this study, the mandible, characterized as hypoplastic in Cohen syndrome, appears to be in a normal position; what really exists is a maxillary hyperplasia of genetic origin. We also put forward an observation hitherto undescribed in the literature: dental agenesis.