Cell therapy with hiPSC-derived RPE cells and RPCs prevents visual function loss in a rat model of retinal degeneration.

Photoreceptor loss is the principal cause of blindness in retinal degenerative diseases (RDDs). Whereas some therapies exist for early stages of RDDs, no effective treatment is currently available for later stages, and once photoreceptors are lost, the only option to rescue vision is cell transplantation. With the use of the Royal College of Surgeons (RCS) rat model of retinal degeneration, we sought to determine whether combined transplantation of human-induced pluripotent stem cell (hiPSC)-derived retinal precursor cells (RPCs) and retinal pigment epithelial (RPE) cells was superior to RPE or RPC transplantation alone in preserving retinal from degeneration. hiPSC-derived RPCs and RPE cells expressing (GFP) were transplanted into the subretinal space of rats. In vivo monitoring showed that grafted cells survived 12 weeks in the subretinal space, and rats treated with RPE + RPC therapy exhibited better conservation of the outer nuclear layer (ONL) and visual response than RPE-treated or RPC-treated rats. Transplanted RPE cells integrated in the host RPE layer, whereas RPC mostly remained in the subretinal space, although a limited number of cells integrated in the ONL. In conclusion, the combined transplantation of hiPSC-derived RPE and RPCs is a potentially superior therapeutic approach to protect retina from degeneration in RDDs.

Transcriptomics analysis of Ccl2/Cx3cr1/Crb1rd8 deficient mice provides new insights into the pathophysiology of progressive retinal degeneration.

Chronic oxidative stress and immune dysregulation are key mechanisms involved in the pathogenesis of most retinal degenerative diseases, including age-related macular degeneration. The Ccl2-/-/Cx3cr1-/-/Crb1rd8/rd8 mouse model develops a progressive degeneration phenotype, with photoreceptor atrophy, drusen-like lesions or pigment alterations at an early age; however, the role of oxidative stress and immune function in the pathogenesis of the model is poorly understood. We performed a comprehensive characterization of the Ccl2-/-/Cx3cr1-/-/Crb1rd8/rd8 mouse to evaluate how these pathways influence pathogenesis. We generated a Ccl2-/-/Cx3cr1-/- double-knockout (DKO) mouse on a C57BL/6N background (with the rd8 mutation of the Crb1 gene), assessed its retina status and function during 9 months in both in vivo and post-mortem analysis, and performed a comprehensive transcriptomic analysis. DKOrd8 mice presented focal retinal lesions with increased infiltration of microglia and involvement of Müller cells. Lesions progressed to thinning of the photoreceptor nuclear layer, causing a loss in retinal function. Transcriptomics analysis revealed major differential expression of genes involved in oxidative stress and neuronal function, in particular genes related to the mitochondrial electron transport chain and antioxidant cellular response. Our results suggest that alterations in chemokine signaling combined with the rd8 mutation in Ccl2-/-/Cx3cr1-/-/Crb1rd8/rd8 mice involve early changes in several pathways associated with age-related macular degeneration, highlighting the relevance of these processes in the pathological retinal degeneration in the DKOrd8 model.

Expression of Melatonin and Dopamine D3 Receptor Heteromers in Eye Ciliary Body Epithelial Cells and Negative Correlation with Ocular Hypertension.

BACKGROUND: Experiments in the late nineties showed an inverse relationship in the eye levels of melatonin and dopamine, thereby constituting an example of eye parameters that are prone to circadian variations. The underlying mechanisms are not known but these relevant molecules act via specific cell surface dopamine and melatonin receptors. This study investigated whether these receptors formed heteromers whose function impact on eye physiology. We performed biophysical assays to identify interactions in heterologous systems. Particular heteromer functionality was detected using Gi coupling, MAPK activation, and label-free assays. The expression of the heteroreceptor complexes was assessed using proximity ligation assays in cells producing the aqueous humor and human eye samples. Dopamine D3 receptors (D3Rs) were identified in eye ciliary body epithelial cells. We discovered heteromers formed by D3R and either MT1 (MT1R) or MT2 (MT2R) melatonin receptors. Heteromerization led to the blockade of D3R-Gi coupling and regulation of signaling to the MAPK pathway. Heteromer expression was negatively correlated with intraocular hypertension. CONCLUSIONS: Heteromers likely mediate melatonin and dopamine actions in structures regulating intraocular pressure. Significant expression of D3R-MT1R and D3R-MT1R was associated with normotensive conditions, whereas expression diminished in a cell model of hypertension. A clear trend of expression reduction was observed in samples from glaucoma cases. The trend was marked but no statistical analysis was possible as the number of available eyes was 2.

Potentiation of cannabinoid signaling in microglia by adenosine A2A receptor antagonists.

Neuroprotective M2-skewed microglia appear as promising to alter the course of neurodegenerative diseases and G protein-coupled receptors (GPCRs) are potential targets to achieve such microglial polarization. A common feature of adenosine A2A (A2A R) and cannabinoid CB2 (CB2 R) GPCRs in microglia is that their expression is upregulated in Alzheimer's disease (AD). On the one hand, CB2 R seems a target for neuroprotection, delaying neurodegenerative processes like those associated to AD or Parkinson's diseases. A2A R antagonists reduce amyloid burden and improve cognitive performance and memory in AD animal models. We here show a close interrelationship between these two receptors in microglia; they are able to physically interact and affect the signaling of each other, likely due to conformational changes within the A2A -CB2 receptor heteromer (A2A -CB2 Het). Particularly relevant is the upregulation of A2A -CB2 Het expression in samples from the APPSw ,Ind AD transgenic mice model. The most relevant finding, confirmed in both heterologous cells and in primary cultures of microglia, was that blockade of A2A receptors results in increased CB2 R-mediated signaling. This heteromer-specific feature suggests that A2A R antagonists would potentiate, via microglia, the neuroprotective action of endocannabinoids with implications for AD therapy.

Evaluation of bariatric surgery patients at the emergency department of a tertiary referral hospital.

OBJECTIVE: To describe the profile of the bariatric surgery patients that were admitted to the Emergency Department (ED). METHOD: A retrospective review of the reasons why bariatric surgery patients go to our ED. We analyzed the first 30 days after the surgery. We evaluated the number and indications of admissions, the examinations ordered, and final diagnosis and destination of the patients. RESULTS: From January 2010 to July 2012, 320 patients underwent bariatric surgery at our Institution. Fifty three patients (16.6%) were admitted to the ED at least once. We found 58 admissions (1.1 admissions by patient). Patients who had duodenal switch and Roux-en-Y gastric bypass were the most representative (74%). The main indications for admission were abdominal pain (50%), and problems related to the surgical wounds (22.4%). Blood test was the most performed examination (75.9%). The most frequent final diagnosis was unspecific abdominal pain in 27 cases (46.6%), and complications of the surgical wound in 10 patients (17.2%). Nineteen patients (35.84%) were admitted to the surgical ward from the ED, and 5 of them required surgical revision (9.4%). Multivariate analyses showed that the type of surgery was the only predictor variable for the ED admission. CONCLUSIONS: Attending ED after bariatric surgery is not common, and less than a third of the patients required hospital admission. Just a small percentage of the examinations showed any pathological value. Readmission rate is very low. Surgical procedure is the only predictor for ED admission.

One stage laparoscopic left adrenalectomy and sleeve gastrectomy by direct supragastric approach.

INTRODUCTION: The advances in laparoscopic surgical technique and the greater experience of surgical teams have enabled the combination of different surgical techniques in a single procedure. This paper presents a case of a sleeve gastrectomy and a left adrenalectomy by laparoscopy for a morbidly obese patient with Cushing's syndrome. PRESENTATION OF CASE: A 52 year-old male patient with a BMI of 53kg/m(2) was diagnosed as having Cushing's syndrome caused by a left adrenal tumor. Sleeve gastrectomy was performed according to the usual technique. The adrenalectomy was performed at the same time by a left supragastric approach. The evolution was favorable, with 52% of excess weight loss observed after six months. Plasma and urinary cortisol at the 3- and 6-month follow-ups were under normal range and the patient required glucocorticoid therapy, confirming the cure of Cushing's syndrome. DISCUSSION: Teams with experience of advanced laparoscopic surgery can successfully combine complex procedures in one surgical period. The approach we used for the adrenalectomy proved itself to be feasible after the sleeve gastrectomy. CONCLUSION: Both procedures can be safely done in experience teams. Sleeve gastrectomy facilitates the direct supragastric approach.

[Laparoscopic Gastric Plication: a new surgery for the treatment of morbid obesity]. / Gastroplastia tubular plicada, una nueva técnica para el tratamiento de la obesidad mórbida.

INTRODUCTION: Laparoscopic Gastric Plication is a new technique derived from sleeve gastrectomy. Plication of the greater curvature produces a restrictive mechanism that causes weight loss. The results of the first cases where this technique has been applied in this hospital are presented. METHODS: A review was made of patients operated on in our hospital between November 2009 and December 2010. Plication of the gastric greater curvature was performed under general anaesthetic and by laparoscopy using 3 lines of sutures and with an orogastric probe as a guide. The results of the morbidity, mortality and weight loss are presented. RESULTS: A total of 13 patients were operated on (7 women). The maximum body mass index (BMI) varied between 37.11 kg/m² and 51.22 kg/m² at the time of the operation. The most frequently found morbidity was nausea and vomiting. Two patients required further surgery due intractable vomiting and total dysphagia; in one the plication unfolded, and in the second it was converted into vertical gastrectomy. CONCLUSIONS: Laparoscopic Gastric Plication is a new surgical technique which gives equivalent short-term results as vertical gastrectomy. It is a reproducible and reversible technique with results and indications still to be validated.