Clinical islet isolation outcomes with a highly purified neutral protease for pancreas dissociation

Background: Pancreas dissociation is a critical initial component of the islet isolation procedure and introduces high variability based on factors including the enzyme type, specificity and potency. Product refinement and alterations to the application strategies have improved isolation outcomes over time; however, islet utilization from donor organs remains low. In this study we evaluate a low endotoxin-high activity grade neutral protease in clinical islet isolation.

Materials and Methods: The use of a non-collagenolytic enzyme, either thermolysin or high active neutral protease, was randomized in clinical islet isolations to evaluate efficacy. Additionally a retrospective comparison to neutral protease NB was conducted.

Results:The thermolysin group had lower trapped islet population and increased purity and post-culture islet mass in comparison to high active grade neutral protease. Comparison of neutral protease NB GMP grade to high active neutral protease displayed no measurable difference in islet mass or viability and transplantation outcomes at 1 mo post-transplant were favorable for both groups.

Conclusions: High activity neutral protease can generate clinical grade islets and may prove beneficial to islet function and viability based on a reduced endotoxin load but dosing of neutral protease requires ongoing optimization.     

Glycogen synthase kinase-3 (GSK-3) regulates TGF-β1-induced differentiation of pulmonary fibroblasts

Background

Chronic lung diseases such as asthma, COPD and pulmonary fibrosis are characterized by abnormal extracellular matrix (ECM) turnover. TGF-β is a key mediator stimulating ECM production by recruiting and activating lung fibroblasts and initiating their differentiation process into more active myofibroblasts. Glycogen synthase kinase-3 (GSK-3) regulates various intracellular signalling pathways; its role in TGF-β₁-induced myofibroblast differentiation is currently largely unknown.

Purpose

To determine the contribution of GSK-3 signalling in TGF-β₁-induced myofibroblast differentiation.

Experimental Approach

We used MRC5 human lung fibroblasts and primary pulmonary fibroblasts of individuals with and without COPD. Protein and mRNA expression were determined by immunoblotting and RT-PCR analysis respectively.

Results

Stimulation of MRC5 and primary human lung fibroblasts with TGF-β₁ resulted in time- and dose-dependent increases of α-sm-actin and fibronectin expression, indicative of myofibroblast differentiation. Pharmacological inhibition of GSK-3 by SB216763 dose-dependently attenuated TGF-β₁-induced expression of these myofibroblasts markers. Moreover, silencing of GSK-3 by siRNA or pharmacological inhibition by CT/CHIR99021 fully inhibited the TGF-β₁-induced expression of α-sm-actin and fibronectin. The effect of GSK-3 inhibition on α-sm-actin expression was similar in fibroblasts from individuals with and without COPD. Neither smad, NF-κB nor ERK1/2 were involved in the inhibitory actions of GSK-3 inhibition by SB126763 on myofibroblast differentiation. Rather, SB216763 increased the phosphorylation of CREB, which in its phosphorylated form acts as a functional antagonist of TGF-β/smad signalling.

Conclusion and Implication

We demonstrate that GSK-3 signalling regulates TGF-β₁-induced myofibroblast differentiation by regulating CREB phosphorylation. GSK-3 may constitute a useful target for treatment of chronic lung diseases.     

Design of a randomised controlled trial on immune effects of acidic and neutral oligosaccharides in the nutrition of preterm infants: carrot study

Background

Overweight and obesity are increasing among children all over the world. Socio-economic factors may influence the development of overweight and obesity in childhood, and it has been proposed that breastfeeding may protect against obesity. The aim of our study was to examine the relationship between exclusive breastfeeding and obesity when potential confounders, such as socioeconomic factors, are considered.

Methods

The data analyzed was from ABIS (All Babies in Southeast Sweden), a prospective cohort study. All parents with children born between October 1, 1997 and October 1, 1999 in Southeast Sweden (n = 21,700) were asked to participate. Parents were asked to answer periodic questionnaires from the time of the child's birth (n = 16,058) until he/she was five years of age (n = 7,356). Cutoffs for overweight and obesity were defined according to Cole et al, age and gender adjusted. Short-term exclusive breastfeeding was defined as < 4 months of exclusive breastfeeding. Multiple logistic regressions were used to identify variables that predict the child's BMI (Body Mass Index) at five years of age.

Results

At five years of age, 12.9% of the children in the study wereoverweight and 4.3% were obese. At the age of three months, 78.4% of the children were being breastfed exclusively. The median exclusive breastfeeding duration was four months. High maternal BMI > 30 (AOR = 1.07; CI = 1.05–1.09; P < 0.001), maternal smoking (AOR = 1.43; CI = 1.05–1.95; P = 0.023) and being a single parent (AOR = 2.10; CI = 1.43–3.09; P < 0.001) were associated with short-term exclusive breastfeeding (less than 4 months). Short-term exclusive breastfeeding was less common if one of the parents had a university degree (Mother: AOR = 0.74; CI = 0.61–0.90; P = 0.003 Father: AOR = 0.73; CI = 0.58–0.92; P = 0.008) or if the father was more than 37 years old (AOR = 0.74; CI = 0.55–0.99; P = 0.045). Short-term exclusive breastfeeding was associated with obesity in five-year-old children (simple logistic regression: OR = 1.44; CI = 1.00–2.07; P = 0.050), but when including other independent factors in the analysis, short-term exclusive breastfeeding did not attain statistical significance.

Conclusion

We cannot exclude the possibility that exclusive breastfeeding influences weight development, but it does not seem to protect against obesity at five years of age.     

Increased risk of second malignancy in pancreatic intraductal papillary mucinous tumors: Review of the literature

AIM: To analyze the available evidence about the risk of extrapancreatic malignancies and pancreatic ductal adenocarcinoma associated to pancreatic intraductal papillary mucinous tumors (IPMNs).METHODS: A systematic search of literature was undertaken using MEDLINE, EMBASE, Cochrane and Web-of-Science libraries. No limitations for year of publication were considered; preference was given to English papers. All references in selected articles were further screened for additional publications. Both clinical series and Literature reviews were selected. For all eligible studies, a standard data extraction form was filled in and the following data were extracted: study design, number of patients, prevalence of pancreatic cancer and extrapancreatic malignancies in IPMN patients and control groups, if available.RESULTS: A total of 805 abstracts were selected and read; 25 articles were considered pertinent and 17 were chosen for the present systematic review. Eleven monocentric series, 1 multicentric series, 1 case-control study, 1 population-based study and 3 case report were included. A total of 2881 patients were globally analyzed as study group, and the incidence of pancreatic cancer and/or extrapancreatic malignancies ranged from 5% to 52%, with a mean of 28.71%. When a control group was analyzed (6 papers), the same incidence was as low as 9.4%.CONCLUSION: The available Literature is unanimous in claiming IPMNs to be strongly associated with pancreatic and extrapancreatic malignancies. The consequences in IPMNs management are herein discussed.