SEC24A deficiency lowers plasma cholesterol through reduced PCSK9 secretion.

The secretory pathway of eukaryotic cells packages cargo proteins into COPII-coated vesicles for transport from the endoplasmic reticulum (ER) to the Golgi. We now report that complete genetic deficiency for the COPII component SEC24A is compatible with normal survival and development in the mouse, despite the fundamental role of SEC24 in COPII vesicle formation and cargo recruitment. However, these animals exhibit markedly reduced plasma cholesterol, with mutations in Apoe and Ldlr epistatic to Sec24a, suggesting a receptor-mediated lipoprotein clearance mechanism. Consistent with these data, hepatic LDLR levels are up-regulated in SEC24A-deficient cells as a consequence of specific dependence of PCSK9, a negative regulator of LDLR, on SEC24A for efficient exit from the ER. Our findings also identify partial overlap in cargo selectivity between SEC24A and SEC24B, suggesting a previously unappreciated heterogeneity in the recruitment of secretory proteins to the COPII vesicles that extends to soluble as well as trans-membrane cargoes. DOI:http://dx.doi.org/10.7554/eLife.00444.001

Desalted Duck Egg White Peptides Promote Calcium Uptake and Modulate Bone Formation in the Retinoic Acid-Induced Bone Loss Rat and Caco-2 Cell Model

Desalted duck egg white peptides (DPs) have been proven to promote calcium uptake in Caco-2 cells and rats treated with a calcium-deficient diet. The retinoic acid-induced bone loss model was used to evaluate the effect of DPs on calcium absorption and bone formation. Three-month-old Wistar female rats were treated with 0.9% saline, DPs (800 mg/kg), or alendronate (5 mg/kg) for three weeks immediately after retinoic acid treatment (80 mg/kg) once daily for two weeks. The model group was significantly higher in serum bone alkaline phosphatase than the other three groups (p < 0.05), but lower in calcium absorption rate, serum osteocalcin, bone weight index, bone calcium content, bone mineral density, and bone max load. After treatment with DPs or alendronate, the absorption rate increased and some serum and bone indices recovered. The morphology results indicated bone tissue form were ameliorated and numbers of osteoclasts decreased after supplementation with DPs or alendronate. The in vitro study showed that the transient receptor potential vanilloid 6 (TRPV6) calcium channel was the main transport pathway of both DPs and Val-Ser-Glu-Glu peptitde (VSEE), which was identified from DPs. Our results indicated that DPs could be a promising alternative to current therapeutic agents for bone loss because of the promotion of calcium uptake and regulation of bone formation

A gold-triggered dearomative spirocarbocyclization/Diels-Alder reaction cascade towards diverse bridged N-heterocycles

A rapid approach for the diversity-oriented synthesis of complex bridged polycyclic N-heterocycles from readily available starting materials in two operational steps has been developed. This strategy firstly introduces molecular diversity by an Ugi four-component reaction, and then achieves these bridged N-heterocycles via an efficient gold-triggered chemo- and diastereoselective cascade non-oxidative ortho-dearomative spirocarbocyclization/Diels-Alder reaction sequence. The application of microwave irradiation for this cascade process efficiently shortens the reaction time to 10 minutes and improves the diastereoselectivity.status: publishe

Facile construction of diverse polyheterocyclic scaffolds via gold-catalysed dearomative spirocyclization/1,6-addition cascade

A gold-catalysed post-Ugi chemo- and diastereoselective cascade dearomative spirocyclization/1,6-addition sequence is disclosed for the synthesis of diverse fused polyheterocyclic scaffolds bearing indole, pyrrole, benzothiophene, furan or electron-rich arene moieties from easily available building blocks. The effectiveness and efficiency of this diversity-oriented approach has been proved in the rapid construction of 28 fused polyheterocyclic scaffolds with a good building-block variability and structural complexity in two operational steps

Sleep disturbance and psychological distress are associated with functional dyspepsia based on Rome III criteria

Abstract Background Functional dyspepsia (FD) is considered a bio-psychosocial disorder. The role of psychosocial factors in FD pathogenesis remains unclear. Methods This study evaluated sleep quality and mood symptoms in patients with FD, assessing the associations of FD severity, disordered sleep, and psychological symptoms. One-hundred-and-fifteen adult patients with typical FD symptoms were enrolled alongside 61 healthy volunteers. Rome III criteria were used to evaluate FD symptoms; sleep disorder was assessed with the Pittsburgh Sleep Quality Index (PSQI), and Symptom Checklist-90-Revised (SCL-90R) was utilized to determine the status of depression, anxiety and other psychological symptoms. Results PSQI scores and nine symptomatic dimensions of SCL-90R were significantly higher in FD patients than in controls. Multiple logistic regression indicated that lower BMI, lower level of education, and sleep disturbance were independently associated with FD and FD subgroups. Hostility and phobic anxiety were independent risk factors for FD. Further analysis showed that hostility was an independent risk factor for both FD subgroups, and somatization and additional psychiatric symptoms for epigastric pain syndrome. Conclusions We found that FD was associated with sleep disorder and psychopathological factors. These findings suggest that implementing sleeping and/or psychological therapies may help reduce FD symptoms

Facile construction of diverse polyheterocyclic scaffolds via gold-catalysed dearomative spirocyclization/1,6-addition cascade

A gold-catalysed post-Ugi chemo- and diastereoselective cascade dearomative spirocyclization/1,6-addition sequence is disclosed for the synthesis of diverse fused polyheterocyclic scaffolds bearing indole, pyrrole, benzothiophene, furan or electron-rich arene moieties from easily available building blocks. The effectiveness and efficiency of this diversity-oriented approach has been proved in the rapid construction of 28 fused polyheterocyclic scaffolds with a good building-block variability and structural complexity in two operational steps.status: publishe

Modular Access to Diverse Bridged Indole Alkaloid Mimics via a Gold-Triggered Cascade Dearomative Spirocarbocyclization/[4+2] Cycloaddition Sequence

A modular and streamlined synthetic strategy for the generation of bridged indole alkaloid-like heterocycles from easily available building blocks is elaborated. This approach utilizes an Ugi four-component reaction, establishing diversity, followed by an efficient cationic gold-triggered intramolecular cascade non-oxidative dearomative spirocarbocyclization/concerted [4 + 2] cyclization cascade, furnishing these architecturally complex and distinct bridged heterocyclic scaffolds with good diastereoselectivity.status: publishe

Modular Access to Diverse Bridged Indole Alkaloid Mimics via a Gold-Triggered Cascade Dearomative Spirocarbocyclization/[4 + 2] Cycloaddition Sequence

A modular and streamlined synthetic strategy for the generation of bridged indole alkaloid-like heterocycles from easily available building blocks is elaborated. This approach utilizes an Ugi four-component reaction, establishing diversity, followed by an efficient cationic gold-triggered intramolecular cascade non-oxidative dearomative spirocarbocyclization/concerted [4 + 2] cyclization cascade, furnishing these architecturally complex and distinct bridged heterocyclic scaffolds with good diastereoselectivity

Access to Polycyclic Azepino[5,4,3-cd]indoles via a Gold-Catalyzed Post-Ugi Dearomatization Cascade.

The development of a rapid and diverse access to complex natural product-like 3,4-fused indole scaffolds has always attracted considerable attention from synthetic and medicinal communities. We herein disclose a modular and straightforward protocol to prepare the densely substituted polycyclic azepino[5,4,3-cd]indole scaffolds. This synthetic process involves an Ugi four-component reaction from easily available starting materials and a gold-catalyzed post-Ugi domino dearomatization/Michael addition sequence, enabling facile access to the highly functionalized azepino[5,4,3-cd]indole core with excellent chemo-, regio-, and diastereoselectivity.status: publishe