3-Carboxamido-5-aryl-isoxazoles as new CB2 agonists for the treatment of colitis

Recent investigations showed that anandamide, the main endogenous ligand of CB₁ and CB₂ cannabinoid receptors, possesses analgesic, antidepressant and anti-inflammatory effects. In the perspective to treat inflammatory bowel disease (IBD), our approach was to develop new selective CB₂ receptor agonists without psychotropic side effects associated to CB₁ receptors. In this purpose, a new series of 3-carboxamido-5-aryl-isoxazoles, never described previously as CB₂ receptor agonists, was designed, synthesized and evaluated for their biological activity. The pharmacological results have identified great selective CB₂ agonists with in vivo anti-inflammatory activity in a DSS-induced acute colitis mouse model.     

Glucose-responsive insulin and glucagon delivery (dual-hormone artificial pancreas) in adults with type 1 diabetes: a randomized crossover controlled trial

Background:

Most patients with type 1 diabetes do not achieve their glycemic targets. We aimed to assess the efficacy of glucose-responsive insulin and glucagon closed-loop delivery for controlling glucose levels in adults with type 1 diabetes.

Methods:

We conducted a randomized crossover trial involving 15 adults with type 1 diabetes, comparing standard insulin-pump therapy with dual-hormone, closed-loop delivery. Patients were admitted twice to a clinical research facility and received, in random order, both treatments. Each 15-hour visit (from 1600 to 0700) included an evening exercise session, followed by a medium-sized meal, a bedtime snack and an overnight stay. During visits that involved closed-loop delivery, basal insulin and glucagon miniboluses were delivered according to recommendations based on glucose sensor readings and a predictive dosing algorithm at 10-minute intervals. During visits involving standard insulin-pump therapy (control visits), patients used conventional treatment.

Results:

Dual-hormone closed-loop delivery increased the percentage of time for which patients’ plasma glucose levels were in the target range (median 70.7% [interquartile range (IQR) 46.1%–88.4%] for closed-loop delivery v. 57.3% [IQR 25.2%–71.8%] for control, p = 0.003) and decreased the percentage of time for which plasma glucose levels were in the low range (bottom of target range [< 4.0 mmol/L], 0.0% [IQR 0.0%–3.0%] for closed-loop delivery v. 10.2% [IQR 0.0%–13.0%] for control, p = 0.01; hypoglycemia threshold [< 3.3 mmol/L], 0.0% [IQR 0.0%–0.0%] for closed-loop delivery v. 2.8% [IQR 0.0%–5.9%] for control, p = 0.006). Eight participants (53%) had at least 1 hypoglycemic event (plasma glucose < 3.0 mmol/L) during standard treatment, compared with just 1 participant (7%) during closed-loop treatment (p = 0.02).

Interpretation:

Dual-hormone, closed-loop delivery guided by advanced algorithms improved short-term glucose control and reduced the risk of hypoglycemia in a group of 15 adults with type 1 diabetes. Trial registration: ClinicalTrials.gov, no. {"type":"clinical-trial","attrs":{"text":"NCT01297946","term_id":"NCT01297946"}}NCT01297946.The Diabetes Control and Complications Trial has shown that intensive insulin therapy in type 1 diabetes with the aim of good glycemic control substantially reduces microvascular and macrovascular complications.^1,2 However, despite advances in insulin analogs, insulin pumps and continuous glucose-monitoring systems, glucose control remains problematic, and most patients with type 1 diabetes do not achieve their glycemic targets.³Hypoglycemia remains the major barrier to the intensification of insulin therapy.⁴ Intensive insulin therapy and lower levels of glycated hemoglobin are unfortunately associated with an increased risk of hypoglycemia.⁵ The frequency of patient-reported nonsevere hypoglycemia (blood glucose ≤ 3.5 mmol/L, with or without symptoms) is about 2.7 episodes/patient per week,⁶ with episodes commonly occuring during the night. In a recent continuous glucose-monitoring trial conducted by the Juvenile Diabetes Research Foundation,⁷ hypoglycemia (glucose sensor reading < 3.3 mmol/L) occurred during 8.5% of the nights included in the study period, with 47% of those nights involving at least 1 hour of hypoglycemia, 23% involving at least 2 hours, and 11% involving at least 3 hours.Advances in insulin infusion pumps and continuous glucose-monitoring systems could improve glycemic control;⁸ however, we still lack the ability to combine these devices in an automated manner. Closed-loop insulin delivery systems (i.e., the artificial pancreas) combine the 2 devices using a mathematical algorithm.⁹ These systems might improve glycemic control and reduce the risk of hypoglycemia compared with conventional insulin-pump therapy (i.e., continuous subcutaneous insulin infusion).^10,11 However, a clinically significant number of hypoglycemic events (blood glucose < 3.0 mmol/L) were still reported during tests of closed-loop delivery systems.^10,11Dual-hormone closed-loop delivery systems have also been proposed to regulate glucose levels. These systems combine insulin delivery with subcutaneous glucagon delivery to further reduce the risk of hypoglycemia.^12–14 However, their potential benefits to improve glycemic control are currently unknown. We sought to determine whether dual-hormone closed-loop delivery, compared with conventional insulin pump therapy, can improve glycemic control and reduce the risk of hypoglycemia in adults with type 1 diabetes.     

Unclosed HIV-1 Capsids Suggest a Curled Sheet Model of Assembly

The RNA genome of retroviruses is encased within a protein capsid. To gather insight into the assembly and function of this capsid, we used electron cryotomography to image human immunodeficiency virus (HIV) and equine infectious anemia virus (EIAV) particles. While the majority of viral cores appeared closed, a variety of unclosed structures including rolled sheets, extra flaps, and cores with holes in the tip were also seen. Simulations of nonequilibrium growth of elastic sheets recapitulated each of these aberrations and further predicted the occasional presence of seams, for which tentative evidence was also found within the cryotomograms. To test the integrity of viral capsids in vivo, we observed that ~ 25% of cytoplasmic HIV complexes captured by TRIM5α had holes large enough to allow internal green fluorescent protein (GFP) molecules to escape. Together, these findings suggest that HIV assembly at least sometimes involves the union in space of two edges of a curling sheet and results in a substantial number of unclosed forms.     

Serum profile in preeclampsia and intra-uterine growth restriction revealed by iTRAQ technology

In order to identify new protein markers modified in placental diseases, high-throughput analysis of proteins in the plasma of pregnant women was carried out for normal and pathological pregnancies (Preeclampsia and/or Intra-Uterine Growth Restriction) using iTRAQ technology. We could identify 166 proteins that were modified (p < 0.05) and the technique used allowed the detection of previously undetected factors, such as various members of the SERPINA clade. The modifications of two proteins (C reactive protein and antichymotrypsin, SERPINA3) were validated on individual samples. Complement and coagulation cascades proteins were significantly enriched among modified protein clusters in the case of intra-uterine growth restriction (p < 2.6 · 10^? 11). Several proteins were specifically enriched in isolated preeclampsia and depleted when preeclampsia was complicated by intra-uterine growth restriction. These findings suggest that the growth restricted foeto-placental unit is able to moderate some changes in maternal plasma composition. Overall, the use of iTRAQ technology, for the first time on this subject, enabled us to provide a new list of proteins modified in placental diseases, among which proteins expressed at a low level that were not accessible by other methods.     

A region within the C-terminal domain of Ure2p is shown to interact with the molecular chaperone Ssa1p by the use of cross-linkers and mass spectrometry

The propagation of yeast prion phenotypes is highly dependent on molecular chaperones. We previously demonstrated that the molecular chaperone Ssa1p sequesters Ure2p in high molecular weight, assembly incompetent oligomeric species. We also determined the affinity of Ssa1p for Ure2p, and its globular domain. To map the Ure2p-Ssa1p interface, we have used chemical cross-linkers and MS. We demonstrate that Ure2p and Ssa1p form a 1 : 1 complex. An analytical strategy combining in-gel digestion of cross-linked protein complexes, and both MS and MS/MS analysis of proteolytic peptides, allowed us to identify a number of peptides that were modified because they are exposed to the solvent. A difference in the exposure to the solvent of a single lysine residue, lysine 339 of Ure2p, was detected upon Ure2p-Ssa1p complex formation. These observations strongly suggest that lysine 339 and its flanking amino acid stretches are involved in the interaction between Ure2p and Ssa1p. They also reveal that the Ure2p amino-acid stretch spanning residues 327-339 plays a central role in the assembly into fibrils.