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Background: In the field of xenotransplantation, digital image analysis (DIA) is an asset to quantify heterogeneous cell infiltrates around transplanted encapsulated islets. Materials and Methods: RGD-alginate was used to produce empty capsules or to encapsulate neonatal porcine islets (NPI) with different combinations of human pancreatic extracellular matrix (hpECM), porcine mesenchymal stem cells (pMSC) and a chitosan anti-fouling coating. Capsules were transplanted subcutaneously in rats for one month and then processed for immunohistochemistry. Immunostainings for macrophages (CD68) and lymphocytes (CD3) were quantified by DIA in two concentric regions of interest (ROI) around the capsules. DIA replicability and reproducibility were assessed by two blind operators. Repeatability was evaluated by processing the same biopsies at different time points. DIA was also compared with quantification by point counting (PC). Results: Methodology validation: different sizes of ROIs were highly correlated. Intraclass correlation coefficients confirmed replicability and reproducibility. Repeatability showed a very strong correlation with CD3 stains and moderate/strong for CD68 stains. Group comparisons for CD68 IHC at each time point proved internal consistency. Point counting and DIA were strongly correlated with both CD3 and CD68. Capsule biocompatibility: Macrophage infiltration was higher around capsules containing biomaterials than around empty and RGD-alginate- NPI capsules. Lymphocytic infiltration was comparable among groups containing cells and higher than in empty capsules. Conclusion: We validated a semi-automated quantification methodology to assess cellular infiltrates and successfully applied it to investigate graft biocompatibility, showing that neonatal porcine islets encapsulated in alginate alone triggered less infiltration than capsules containing islets and bioactive materials.

Current understanding of fibrosis remains incomplete despite the increasing burden of related diseases. Preclinical models are used to dissect the pathogenesis and dynamics of fibrosis, and to evaluate anti-fibrotic therapies. These studies require objective and accurate measurements of fibrosis. Existing histological quantification methods are operator-dependent, organ-specific, and/or need advanced equipment. Therefore, we developed a robust, minimally operator-dependent, and tissue-transposable digital method for fibrosis quantification. The proposed method involves a novel algorithm for more specific and more sensitive detection of collagen fibers stained by picrosirius red (PSR), a computer-assisted segmentation of histological structures, and a new automated morphological classification of fibers according to their compactness. The new algorithm proved more accurate than classical filtering using principal color component (red-green-blue, RGB) for PSR detection. We applied this new method on established mouse models of liver, lung, and kidney fibrosis and demonstrated its validity by evidencing topological collagen accumulation in relevant histological compartments. Our data also showed an overall accumulation of compact fibers concomitant with worsening fibrosis and evidenced topological changes in fiber compactness proper to each model. In conclusion, we describe here a robust digital method for fibrosis analysis allowing accurate quantification, pattern recognition, and multi-organ comparisons useful to understand fibrosis dynamics.

Ulipristal acetate (UPA), a selective progesterone receptor modulator (SPRM), offers new therapeutic options for the clinical management of large uterine fibroids associated with heavy menstrual bleeding or with other moderate or severe symptoms (bulk symptoms, pelvic pain, decreased quality of life). SPRM are synthetic compounds that exert an agonist or antagonist effect on target tissues by their binding to progesterone receptors. UPA reduces fibroid size, controls bleeding in a high percentage of women and significantly improves quality of life. The present review aims to provide insights into UPA indications and its mechanism of action.

Introduction Vascular hyperpermeability is a major aspect of sepsis pathophysiology. We previously demonstrated that AMPK protects against sepsis induced vascular hyperpermeability by mechanisms involving interendothelial junctions (IEJs) regulation. The SGLT2 inhibitor Canagliflozin, prescribed in diabetes and known for its cardiovascular protective properties, has recently been shown to activate AMPK in different cell types. Objectives Here, we show that Canagliflozin might be considered as a new therapeutic approach against sepsis induced vascular hyperpermeability. We also decipher molecular mechanisms underlying this protective effect. Methods In vivo experiments were performed on endothelial-specific α1AMPK knockout (e-AMPK KO) mice. Canagliflozin administration was achieved by oral gavage (100 mg/kg) and validated by plasmatic dosages. LPS was administered by intraperitoneal injection (10 mg/kg). Myocardial edema was assessed by Evans Blue Dye extravasation measurement. In vitro experiments were performed in Human Dermal Blood Endothelial Cells (HDBEC). α1AMPK was invalidated with a specific siRNA or activated by Canagliflozin (10 μM). Results We show that Canagliflozin activates AMPK in HDBEC at physiological concentrations. Canagliflozin administration strongly protects against LPS induced vascular leakage in WT but not in e-AMPK KO mice. Accordingly, albuminemia is preserved by Canagliflozin treatment in septic WT mice. More interestingly, Canagliflozin treatment increases survival in response to sepsis injury. In vitro, AMPK activation by Canagliflozin preserves the integrity of IEJs (Cx43, VeCad, ZO1). Conclusion Our work demonstrates the protective effects of Canagliflozin on sepsis induced vascular hyperpermeability and mortality, and highlights key molecular mechanisms involved in this protection. This should open the field to consider Canagliflozin as a new therapeutic support of sepsis induced vascular hyperpermeability.

Uterine fibroids are the most common tumors affecting premenopausal women, responsible for bleeding, pain, and reduced quality of life. When symptomatic, their management mainly involves surgery, which is all too often radical (hysterectomy). While surgical options sparing the uterus (hysteroscopic and laparoscopic myomectomy) and other non-surgical approaches do indeed exist, drug-based therapies are associated with lower costs and morbidity rates. Since progesterone is required for fibroid growth, gonadotropin agonists have been used to control bleeding and decrease fibroid volume, but they only represent a temporary remedy due to adverse events. Ulipristal acetate (UPA), a selective progesterone receptor modulator, is indicated for fibroid management. It is safe, provides fast control of bleeding, and causes sustained fibroid volume reduction in the vast majority of cases (80%). Indeed, UPA-treated fibroids shrink by a combination of inhibition of cell proliferation, stimulation of cell death, and fibrosis resorption. In the case of symptom recurrence, repeated intermittent 3-month courses of daily UPA considerably maximize the impact of treatment, sometimes resulting in complete disappearance of treated fibroids. Despite the therapeutic dose of UPA being very well tolerated, patients with liver anomalies or disorders should be excluded at screening according to European Medicines Agency-Pharmacovigilance Risk Assessment Committee (PRAC) recommendations. We therefore propose new algorithms for fibroid management in premenopausal women with symptomatic fibroids, depending on their localization, the patient's wishes, and clinical response, while monitoring liver enzymes and bilirubin, as recommended by the PRAC, in order to minimize the risks of possible liver toxicity.

ContextUlipristal acetate (UPA), a selective progesterone receptor modulator, clinically reduces uterine myoma size in 80% of cases. However, the molecular mechanism of action is still poorly understood, as is the reason why 20% of myomas do not respond to treatment.ObjectiveTo elucidate whether matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) are associated with myoma volume shrinkage after UPA therapy.DesignProspective study.SettingAcademic research unit of a university hospital.PatientsUterine biopsies were obtained from 59 patients with symptomatic myomas undergoing myomectomy, 45 of whom were treated preoperatively with either one or greater than or equal to two, 3-month courses of UPA and 14 not given any hormone therapy to serve as controls. Myoma volume was individually monitored during UPA therapy to determine any substantial clinical response (defined as a reduction in volume of >25%). Three groups were established based on the response to treatment: responsive (R) after one course (n = 12); R after two to four courses (n = 15); and nonresponsive (NR; n = 18).InterventionsUPA treatment given as preoperative management for symptomatic myomas.Main Outcome MeasuresMMP and TIMP expression assessed by zymography and immunohistochemistry.ResultsCompared with controls and NR myomas, responders showed significantly higher expression levels for MMP-1 (P < 0.0001) and MMP-2 (P = 0.009) and significantly lower expression levels for TIMP-1 (P = 0.040).ConclusionsThe correlation found between MMP expression and volume fold change supports the notion that MMPs play a key role in UPA-induced myoma shrinkage.