Fetuin-A is a HIF target that safeguards tissue integrity during hypoxic stress

Intrauterine growth restriction (IUGR) is associated with reduced kidney size at birth, accelerated renal function decline, and increased risk for chronic kidney and cardiovascular diseases in adults. Precise mechanisms underlying fetal programming of adult diseases remain largely elusive and warrant extensive investigation. Setting up a mouse model of hypoxia-induced IUGR, fetal adaptations at mRNA, protein and cellular levels, and their long-term functional consequences are characterized, using the kidney as a readout. Here, we identify fetuin-A as an evolutionary conserved HIF target gene, and further investigate its role using fetuin-A KO animals and an adult model of ischemia-reperfusion injury. Beyond its role as systemic calcification inhibitor, fetuin-A emerges as a multifaceted protective factor that locally counteracts calcification, modulates macrophage polarization, and attenuates inflammation and fibrosis, thus preserving kidney function. Our study paves the way to therapeutic approaches mitigating mineral stress-induced inflammation and damage, principally applicable to all soft tissues.

Evaluation of the MDACC clinical classification system for pancreatic cancer patients in an European multicenter cohort

BACKGROUND

The MDACC group recommends to extend the current borderline classification for pancreatic cancer into three groups: type A patients with resectable/borderline tumor anatomy, type B with resectable/borderline resectable tumor anatomy and clinical findings suspicious for extrapancreatic disease and type C with borderline resectable and marginal performance status/severe pre-existing comorbidity profile or age>80. This study intents to evaluate the proposed borderline classification system in a multicenter patient cohort without neoadjuvant treatment.

METHODS

Evaluation was based on a multicenter database of pancreatic cancer patients undergoing surgery from 2005 to 2016 (n = 1020). Complications were classified based on the Clavien-Dindo classification. χ²-test, Kaplan-Meier estimator and Cox regression hazard model were used for statistical analysis.

RESULTS

Most patients (55.1%) were assigned as type A patients, followed by type C (35.8%) and type B patients (9.1%). Neither the complication rate, nor the mortality rate revealed a correlation to any subgroup. Type B patients had a significant worse progression free (p < 0.001) and overall survival (p = 0.005). Type B classification was identified as an independent prognostic marker for progression free survival (p = 0.005, HR 1.47).

CONCLUSION

The evaluation of the proposed classification in a cohort without neoadjuvant treatment did not justify an additional medical borderline subgroup. A new subgroup based on prognostic borderline patients might be the main target group for neoadjuvant protocols in future.

Bilateral uterine vessel ligation as a model of intrauterine growth restriction in mice

BACKGROUND

Intrauterine growth restriction (IUGR) occurs in up to 10% of pregnancies and is considered as a major risk to develop various diseases in adulthood, such as cardiovascular diseases, insulin resistance, hypertension or end stage kidney disease. Several IUGR models have been developed in order to understand the biological processes linked to fetal growth retardation, most of them being rat or mouse models and nutritional models. In order to reproduce altered placental flow, surgical models have also been developed, and among them bilateral uterine ligation has been frequently used. Nevertheless, this model has never been developed in the mouse, although murine tools display multiple advantages for biological research. The aim of this work was therefore to develop a mouse model of bilateral uterine ligation as a surgical model of IUGR.

RESULTS

In this report, we describe the set up and experimental data obtained from three different protocols (P1, P2, P3) of bilateral uterine vessel ligation in the mouse. Ligation was either performed at the cervical end of each uterine horn (P1) or at the central part of each uterine horn (P2 and P3). Time of surgery was E16 (P1), E17 (P2) or E16.5 (P3). Mortality, maternal weight and abortion parameters were recorded, as well as placentas weights, fetal resorption, viability, fetal weight and size. Results showed that P1 in test animals led to IUGR but was also accompanied with high mortality rate of mothers (50%), low viability of fetuses (8%) and high resorption rate (25%). P2 and P3 improved most of these parameters (decreased mortality and improved pregnancy outcomes; improved fetal viability to 90% and 27%, respectively) nevertheless P2 was not associated to IUGR contrary to P3. Thus P3 experimental conditions enable IUGR with better pregnancy and fetuses outcomes parameters that allow its use in experimental studies.

CONCLUSIONS

Our results show that bilateral uterine artery ligation according to the protocol we have developed and validated can be used as a surgical mouse model of IUGR.

Podocyte EphB4 signaling helps recovery from glomerular injury

Eph receptor tyrosine kinases and their ligands (ephrins) have a pivotal role in the homeostasis of many adult organs and are widely expressed in the kidney. Glomerular diseases beginning with mesangiolysis can recover, with podocytes having a critical role in this healing process. We studied here the role of Eph signaling in glomerular disease recovery following mesangiolytic Thy1.1 nephritis in rats. EphB4 and ephrinBs were expressed in healthy glomerular podocytes and were upregulated during Thy1.1 nephritis, with EphB4 strongly phosphorylated around day 9. Treatment with NPV-BHG712, an inhibitor of EphB4 phosphorylation, did not cause glomerular changes in control animals. Nephritic animals treated with vehicle did not have morphological evidence of podocyte injury or loss; however, application of this inhibitor to nephritic rats induced glomerular microaneurysms, podocyte damage, and loss. Prolonged NPV-BHG712 treatment resulted in increased albuminuria and dysregulated mesangial recovery. Additionally, NPV-BHG712 inhibited capillary repair by intussusceptive angiogenesis (an alternative to sprouting angiogenesis), indicating a previously unrecognized role of podocytes in regulating intussusceptive vessel splitting. Thus, our results identify EphB4 signaling as a pathway allowing podocytes to survive transient capillary collapse during glomerular disease.

Complicated sigmoid diverticulitis--Hartmann's procedure or primary anastomosis?

INTRODUCTION

Diverticular disease of the colon is a common condition in developed countries. For perforated diverticulitis Hartmann's procedure is a safe and quick treatment option. But intestinal restoration needs further interventions. This leads to high complication rates and cost. Therefore a critical evaluation of surgical treatment options is necessary.

METHODS

During a period of 18 months 88 patients underwent surgical resection for diverticulitis. Forty patients had emergency surgery. Among those a primary anastomosis was performed in 21 patients. The other 19 patients had interval colostomy. Among 21 patients with primary anastomosis major complications occurred in two patients, vs. twelve in patients with Hartmann's operation (p = 0.03). In the Hartmann group eight patients had major general complications, vs. one patient in the group with primary anastomosis (p = 0.06). The mean hospital stay was 38 days after Hartmann's procedure, vs. 13 days for patients with primary anastomosis (p < 0.01).

CONCLUSION

In emergency surgery for complicated diverticulitis primary anastomosis is not associated with an increased postoperative morbidity. A primary anastomosis reduces the need for further surgical interventions and complex re-operations. Thus, an overall reduction of morbidity, cost, complication rate and hospital stay is possible. Therefore this technique is advantageous for patients and hospitals.

Glycogenome expression dynamics during mouse C2C12 myoblast differentiation suggests a sequential reorganization of membrane glycoconjugates

Background

Several global transcriptomic and proteomic approaches have been applied in order to obtain new molecular insights on skeletal myogenesis, but none has generated any specific data on glycogenome expression, and thus on the role of glycan structures in this process, despite the involvement of glycoconjugates in various biological events including differentiation and development. In the present study, a quantitative real-time RT-PCR technology was used to profile the dynamic expression of 375 glycogenes during the differentiation of C2C12 myoblasts into myotubes.

Results

Of the 276 genes expressed, 95 exhibited altered mRNA expression when C2C12 cells differentiated and 37 displayed more than 4-fold up- or down-regulations. Principal Component Analysis and Hierarchical Component Analysis of the expression dynamics identified three groups of coordinately and sequentially regulated genes. The first group included 12 down-regulated genes, the second group four genes with an expression peak at 24 h of differentiation, and the last 21 up-regulated genes. These genes mainly encode cell adhesion molecules and key enzymes involved in the biosynthesis of glycosaminoglycans and glycolipids (neolactoseries, lactoseries and ganglioseries), providing a clearer indication of how the plasma membrane and extracellular matrix may be modified prior to cell fusion. In particular, an increase in the quantity of ganglioside G_M3 at the cell surface of myoblasts is suggestive of its potential role during the initial steps of myogenic differentiation.

Conclusion

For the first time, these results provide a broad description of the expression dynamics of glycogenes during C2C12 differentiation. Among the 37 highly deregulated glycogenes, 29 had never been associated with myogenesis. Their biological functions suggest new roles for glycans in skeletal myogenesis.