Gold Nanoclusters Enhance the Efficacy of the Polymer-Based Chaperone in Restoring and Maintaining the Native Conformation of Human Islet Amyloid Polypeptide.

The misfolding and un-natural fibrillation of proteins/peptides are associated with many conformation diseases, such as human islet amyloid polypeptide (hIAPP) in type 2 diabetes (T2D). Inspired by molecular chaperones maintaining protein homeostasis in vivo, many polymer-based artificial chaperones were introduced to regulate protein/peptide folding and fibrillation. However, the pure polymer chaperones prefer to agglomerate into large-size micelles in the physiological environment and thus lose their chaperone functions, which greatly restricts the application of polymer-based chaperones. Here, we designed and prepared a core-shell artificial chaperone based on a dozen poly-(N-isopropylacrylamide-co-N-acryloyl-O-methylated-l-arginine) (PNAMR) anchored on a gold-nanocluster (AuNC) core. The introduction of the AuNC core significantly reduced the size and enhanced the efficacy and stability of polymer-based artificial chaperones. The PNAMR@AuNCs, with a diameter of 2.5 ± 0.5 nm, demonstrated exceptional ability in maintaining the natively unfolded conformation of protein away from the misfolding and the following fibrillation by directly binding to the natively unfolded monomolecular hIAPP and hence in preventing their conversion into toxic oligomers. More excitingly, the PNAMR@AuNCs were able to restore the natural unfolded conformation of hIAPP via dissolving the ß-sheet-rich hIAPP fibrils. Considering the uniform molecular mechanism of protein misfolding and fibrillation in conformation disorders, this finding provides a generic therapeutic strategy for neurodegenerative diseases and other conformation diseases by using PNAMR@AuNC artificial chaperones to restore and maintain the native conformation of amyloid proteins.

Gold nanoclusters eliminate obesity induced by antipsychotics.

Obesity induced by antipsychotics have plagued more than 20 million people worldwide. However, no drug is available to eliminate the obesity induced by antipsychotics. Here we examined the effect and potential mechanisms of a gold nanoclusters (AuNCs) modified by N-isobutyryl-L-cysteine on the obesity induced by olanzapine, the most prescribed but obesogenic antipsychotics, in a rat model. Our results showed that AuNCs completely prevented and reversed the obesity induced by olanzapine and improved glucose metabolism profile in rats. Further mechanism investigations revealed that AuNCs exert its anti-obesity function through inhibition of olanzapine-induced dysfunction of histamine H1 receptor and proopiomelanocortin signaling therefore reducing hyperphagia, and reversing olanzapine-induced inhibition of uncoupling-protein-1 signaling which increases thermogenesis. Together with AuNCs' good biocompatibility, these findings not only provide AuNCs as a promising nanodrug candidate for treating obesity induced by antipsychotics, but also open an avenue for the potential application of AuNCs-based nanodrugs in treating general obesity.

Engineering Nanointerfaces of Au25 Clusters for Chaperone-Mediated Peptide Amyloidosis.

Synthetic nanomaterials possessing biomolecular-chaperone functions are good candidates for modulating physicochemical interactions in many bioapplications. Despite extensive research, no general principle to engineer nanomaterial surfaces is available to precisely manipulate biomolecular conformations and behaviors, greatly limiting attempts to develop high-performance nanochaperone materials. Here, we demonstrate that, by quantifying the length (-SCxR±, x = 3-11) and charges (R- = -COO-, R+ = -NH3+) of ligands on Au25 gold nanochaperones (AuNCs), simulating binding sites and affinities of amyloid-like peptides with AuNCs, and probing peptide folding and fibrillation in the presence of AuNCs, it is possible to precisely manipulate the peptides' conformations and, thus, their amyloidosis via customizing AuNCs nanointerfaces. We show that intermediate-length liganded AuNCs with a specific charge chaperone peptides' native conformations and thus inhibit their fibrillation, while other types of AuNCs destabilize peptides and promote their fibrillation. We offer a microscopic molecular insight into peptide identity on AuNCs and provide a guideline in customizing nanochaperones via manipulating their nanointerfaces.

Inhibition of MicroRNA miR-101-3p on prostate cancer progression by regulating Cullin 4B (CUL4B) and PI3K/AKT/mTOR signaling pathways.

To probe into the efffects of miR-101-3p via regulating CUL4B within PI3K/AKT/mTOR signaling pathway on progression of prostate cancer (PCA). Western blot and qRT-PCR were adopted to detect CUL4B and miR-101-3p expressions in 75 cases with PCA . The cellular strains of PCA (LNCaP and PC3) were chose as the objects to check the targeting correlation between CUL4B and miR-101-3p through dual-luciferase reporter experiments. LNCaP cells and PC3 cells were randomly divided into the blank group, miR-101-3p mimic group, siRNA negative control (NC) group, CUL4B siRNA group and CUL4B siRNA plus the miR-101-3p inhibitor group. Cellular bioactivity measurement was done via Cell-Light EDU, MTT, Annexin-V-FITC/PI, scratch-heal experiments and invasion tests of Transwell. MiR-101-3p expression was decreased more signally in tumor tissues than in normal tissues adjacent to the cancer. MiR-101-3p inhibited cellular proliferating, migrating and invasion. Nevertheless, it promoted cellular apoptosis, up-regulated apoptotic proteins as well as down-regulated anti-apoptotic proteins. CUL4B siRNA and miR-101-3p simulation were similar in terms of their outcomes. Nonetheless, these results could be reversed through the miR-101-3p inhibitor. Besides, CUL4B siRNA and the simulation halted a serious of PI3K signal in PCA cells. MiR-101-3p expression was down-regulated in PCA patients. CUL4B was upregulated in PCA patients. Moreover, miR-101-3p suppressed cellular invasion, migration, proliferation and led to cellular apoptosis, which might be related to the PI3K/AKT/mTOR signaling pathway suppression. Finally, we found, MiR-101-3P suppressed PCA progression via aiming for CUL4B, which may offer the new molecular target for PCA clinical treatment.

Ginkgolide A attenuates sepsis-associated kidney damage via upregulating microRNA-25 with NADPH oxidase 4 as the target.

The aim of the present study was to explore the effects of Ginkgolide A (GA) on renal function of mice with sepsis and whether GA could attenuate sepsis-associated inflammation and apoptosis in kidney via upregulating microRNA (miR)-25 with NADPH oxidase 4 (Nox4) as the target. Experiments were carried out on lipopolysaccharide (LPS)-treated mice and kidney tubular (NRK-52E) cells. GA significantly inhibited the increases of creatinine (Cr), blood urea nitrogen (BUN) and cystatin C (CysC) in the serum of LPS-treated mice. The increases of inflammatory factors including tumor necrosis factor (TNF)-α, interleukin (IL)-1ß and IL-6 in the kidneys of LPS-treated mice or NRK-52E cells were inhibited by GA administration. The changes of cleaved-caspase 3, cleaved-caspase 8, Bax, Bcl2 in mouse kidney and NRK-52E cells treated by LPS were reversed by GA administration. The sepsis-induced decrease of miR-25 was enhanced by GA treatment. The LPS-induced increases of inflammatory factors and apoptosis in mouse kidney or NRK-52E cells were attenuated after miR-25 agomiR administration. The bioinformatics analysis and luciferase reporter assays showed that Nox4 was a direct target gene of miR-25. Treatment with miR-25 inhibited Nox4 expression, while Nox4 over-expression reversed the inhibiting effects of miR-25 agomiR on LPS-induced increases of inflammatory factors and apoptosis in NRK-52E cells. These results indicated that GA could improve sepsis-induced renal damage by attenuating renal inflammation and apoptosis via upregulating miR-25 with Nox4 as the target.

Comparison of Retrograde Intrarenal Surgery and Micro-Percutaneous Nephrolithotomy for Kidney Stones: A Meta-Analysis.

BACKGROUND: Advances in micro-percutaneous nephrolithotomy (PCNL) for kidney stones have made it an alternative approach to the retrograde intrarenal surgery (RIRS) approach. Nevertheless, the superiority of micro-PCNL over RIRS is still under debate. The results are controversial. OBJECTIVES: The purpose of this study was to systematically evaluate the clinical results in patients presenting with kidney stones treated with micro-PCNL or RIRS. METHODS: A literature search was done for electronic databases to identify researches that compared micro-PCNL and RIRS till December 2019. The clinical outcome included complications, stone-free rates (SFRs), hemoglobin reduction, length of hospital stay, and operative time. RESULTS: Five articles were included in our study. The pooled results revealed no statistical difference in the rate of complications (OR = 0.99, 95% CI = 0.57-1.74, p = 0.99), length of hospital stay (MD = -0.29, 95% CI = -0.82 to 0.24, p = 0.28), and operative time (MD = -6.63, 95% CI = -27.34 to 14.08, p = 0.53) between the 2 groups. However, significant difference was present in hemoglobin reduction (MD = -0.43, 95% CI = -0.55 to 0.30, p < 0.001) and the SFRs (OR = 0.59, 95% CI = 0.36-0.98, p = 0.04) when comparing RIRS with micro-PCNL. CONCLUSIONS: Compared with micro-PCNL to treat kidney stones, RIRS is associated with better stone clearance and bearing higher hemoglobin loss. As the advantages of both technologies have been shown in some fields, the continuation of well-designed clinical trials may be necessary.

[Factors affecting selection of tracheostomy after mandibular tumor operation: a retrospective study].

PURPOSE: To assess the factors affecting selection of tracheostomy after mandibulectomy. METHODS: The clinical data of 165 patients who were divided into intubated group and tracheostomy group were collected from January 2008 to December 2012 in Shanghai Ninth People's Hospital, including demographics, smoke habits, alcohol consumption, pulmonary disease, American Society of Anesthesiologists (ASA) physical status classification, history of jaw operation, length of surgery, preoperative radiotherapy, free flap reconstruction, resection over the anterior midline, and radical neck dissection. The postoperative outcomes, such as the duration of keeping tube, the length of ICU stay, the length of hospital stay, and the number of complications and death were collected. Statistical analysis was performed using SAS version 9.2 software package. RESULTS: There were 81 patients in intubated group and 84 patients in tracheostomy group. Three factors that might be associated with selection of tracheostomy after mandibulectomy were preoperative radiotherapy (OR: 3.51, 95% CI: 1.34-9.20), free flap reconstruction (OR: 3.99, 95%CI: 1.84-8.65), and resection over the anterior midline of the jaw (OR: 20.08, 95%CI: 6.52-160.35)(P<0.05). CONCLUSIONS: Tracheostomy was suitable for patients who received preoperative radiotherapy, free flap reconstruction and resection over the anterior midline after mandibular tumor resection were factors in considering of tracheotomy.

Bioanalysis of Targeted Nanoparticles in Monkey Plasma via LC-MS/MS.

This work represents the first reporting of a comprehensive bioanalytical GLP methodology detailing the mass spectrometric quantitation of PF-05212384 dosed as a targeted polymeric encapsulated nanoparticle (PF-07034663) to monkeys. Polymeric nanoparticles are a type of drug formulation that enables the sustained release of an active therapeutic agent (payload) for targeted delivery to specific sites of action such as cancer cells. Through the careful design and engineering of the nanoparticle formulation, it is possible to improve the biodistribution and safety of a given therapeutic payload in circulation. However, the bioanalysis of nanoparticles is challenging due to the complexity of the nanoparticle drug formulation itself and the number of pharmacokinetic end points needed to characterize the in vivo exposure of the nanoparticles. Gedatolisib, also known as PF-05212384, was reformulated as an encapsulated targeted polymeric nanoparticle. The bioanalytical assays were validated to quantitate both total and released PF-05212384 derived from the encapsulated nanoparticle (PF-07034663). Assay performance calculated from quality control samples in three batch runs demonstrated intraday precision and accuracy within 10.3 and 12.2%, respectively, and interday precision and accuracy within 9.1 and 8.5%, respectively. This method leveraged automation to ease the burden of a laborious and complicated sample pretreatment and extraction procedure. The automated method was used to support a preclinical safety study in monkeys in which both released and total PF-05212384 concentrations were determined in over 1600 monkey plasma study samples via LC-MS/MS.

Enantioselective synthesis of (-)-maoecrystal V by enantiodetermining C-H functionalization.

The evolution of a program directed at the enantioselective total synthesis of maoecrystal V, a highly modified ent-kauranoid, is described. An early stage chiral auxiliary-directed asymmetric C-H functionalization for the construction of a key benzofuran intermediate enabled the first asymmetric synthesis of the natural enantiomer of maoecrystal V, confirming the assigned stereochemistry. A divergent course of the central intramolecular Diels-Alder reaction, which is dependent on the nature of the dienophile, initially led to the development of an unanticipated and previously unknown isomer of maoecrystal V, which we named maoecrystal ZG. In light of the reported selective and potent cytotoxic activity of maoecrystal V, the cytotoxic properties of maoecrystal ZG were also investigated.

Digitoflavone inhibits IκBα kinase and enhances apoptosis induced by TNFα through downregulation of expression of nuclear factor κB-regulated gene products in human pancreatic cancer cells.

Tumor necrosis factor-α (TNFα) activates both cell death and cell survival pathways. The activation of survival pathway renders most cancer cells resistant to TNF-induced cytotoxicity. We found that pretreatment with digitoflavone, a plant flavonoid, greatly sensitized TNFα-induced apoptotic cell death in several human pancreatic cancer cells. In search of the molecular basis of the sensitization effect of digitoflavone, digitoflavone was found to inhibit TNFα-induced activation of nuclear transcription factor-kappa B (NF-κB) which is the main survival factor in TNFα signaling. NF-κB suppression occurred through inhibition of IκBα kinase activation, IκBα phosphorylation, IκBα degradation, and NF-κB nuclear translocation. This inhibition correlated with suppression of NF-κB-dependent genes involved in antiapoptosis (mcl-1, bcl-2, bcl-xl, c-iap1, c-iap2, flip, and survivin), proliferation (c-myc, cyclin d1), and angiogenesis (vegf, cox-2, and mmp-9). In addition, digitoflavone can activate JNK through inhibition of NF-κB signaling, provide a continuous blockade of the feed-back inhibitory mechanism by JNK-induced NF-κB activation. This study found a novel function of digitoflavone and enhanced the value of digitoflavone as an anticancer agent.

Synthesis and biological evaluation of scopoletin derivatives.

A series of new scopoletin derivatives were designed and synthesized. Their anti-proliferative effect was initially evaluated against various human cancer cell lines. Among the tested compounds, A1, A2, and D6 showed significant anti-proliferative activities. Angiogenesis was detected by endothelial cell migration assay and tube formation study. The results showed that A1, A2, and D6 inhibited the vascular endothelial growth factor (VEGF)-stimulated proliferation, migration, and tube formation of human umbilical vein endothelial cells in vitro. Moreover, they inhibited the vessel growth in the chorioallantoic membrane in vivo. This inhibition was correlated with a significant decrease in the VEGF-triggered phosphorylated forms of ERK1/2 and Akt. In summary, these findings strongly suggested that these scopoletin derivatives might be structurally novel angiogenesis inhibitors.

Escin sodium induces apoptosis of human acute leukemia Jurkat T cells.

Escin sodium has been used in the clinic as an antioedematous, antiexudative and vasoprotective agent for many years and has shown excellent tolerability. However, little is known about its anticancer activity. This is a report for the first time that escin sodium exerts a cytotoxic effect on human acute leukemia Jurkat T cells via the induction of apoptosis rather than cell cycle arrest. Escin sodium activated the initiator caspase-8, -9, and the effector caspase-3, degraded poly (ADP-ribose) polymerase (PARP) and attenuated the expression of Bcl-2. In addition, escin sodium inhibited the growth of cancer cells in a selective manner with Jurkat cells most sensitive to it. Taken together, the data show that escin sodium possesses potent apoptogenic activity toward human acute leukemia Jurkat T cells.

Expression and purification of an antitumor-analgesic peptide from the venom of Mesobuthus martensii Karsch by small ubiquitin-related modifier fusion in Escherichia coli.

To prevent protein aggregation, some proteins are usually expressed as fusion proteins from which target proteins can be released by proteolytic or chemical reagents. In this report, small ubiquitin-related modifier (SUMO) linked with a hexa-histidine tag was used as a fusion partner for the antitumor-analgesic peptide from the venom of Buthus martensii (Karsch) scorpion (AGAP). The optimal expression level of the soluble fusion protein, SUMO-AGAP, was up to 40% of the total cellular protein. The fusion protein was purified by Ni-NTA affinity chromatography and cleaved by a SUMO-specific protease (Ulp1) to obtain the recombinant AGAP (rAGAP), which was further purified by Ni-NTA affinity chromatography. The purified final product was >95% pure by SDS-PAGE stained with Coomassie brilliant blue R-250. Mass spectroscopic analysis indicated the protein to be 7142.63 Dalton, which equaled the theoretically expected mass. N-terminal sequencing of rAGAP showed the sequence corresponded to the native protein. MTT assay indicated the rAGAP could significantly inhibit the proliferation of Jurkat and Hut 78 T lymphoma cell lines. The further writhing experiment showed that the rAGAP had an intensive analgesic effect. The expression strategy presented in this study allows convenient high yield and easy purification of the rAGAP with native sequences.

From allene to allene: a palladium-catalyzed approach to beta-allenyl butenolides and their application to the synthesis of polysubstituted benzene derivatives.

An allene to allene protocol for the synthesis of beta-allenyl butenolides in moderate to high yields from 2,3-allenoic acids and propargylic carbonates catalyzed by Pd(OAc)2-TFP has been developed; the products were applied successfully to the Diels-Alder reaction with electron-deficient alkynes to afford polysubstituted benzene derivatives with an excellent regioselectivity.