Selective Peptide Cysteine Manipulation on Demand and Difficult Protein Chemical Synthesis Enabled by Controllable Acidolysis of N,S-Benzylidene Thioacetals.

Although solid-phase peptide synthesis combining with chemical ligation provides a way to build up customized polypeptides in general, many targets are still presenting challenges for the conventional synthetic process, such as hydrophobic proteins. New methods and strategies are still required to overcome these obstacles. In this study, kinetic studies of Cys/Pen ligation and its acidolysis were performed, from which the fast acidolysis of substituted N,S-benzylidene thioacetals (NBTs) was discovered. The study demonstrates the potential of NBTs as a promising Cys switchable protection, facilitating the chemical synthesis of peptides and proteins by efficiently disrupting peptide aggregation. The compatibility of NBTs with other commonly adopted Cys protecting groups and their applications in sequential disulfide bond formation were also investigated. The first chemical synthesis of the native human programmed death ligand 1 immunoglobulin V-like (PD-L1 IgV) domain was achieved using the NBT strategy, showcasing its potential in difficult protein synthesis.

Exosome inhibition improves response to first-line therapy in small cell lung cancer.

Exosomes are recognized as important mediators of cell-to-cell communication, facilitating carcinogenesis. Although there have been significant advancements in exosome research in recent decades, no drugs that target the inhibition of sEV secretion have been approved for human use. For this study, we employed GW4869 and Nexinhib20 as inhibitors of exosome synthesis and trafficking combined. First, we found that Nexinhib20 and GW4869 effectively inhibited RAB27A and neutral sphingomyelinase 2 (nSMase2) nsMase2. Interestingly, the inhibition of nsMase2 and RAB27A decreased expression of CD9, CD63 and Tsg101, both at RNA and protein levels. We used a combination treatment strategy of cisplatin/etoposide plus GW4869 or Nexinhib20 on small cell lung cancer (SCLC) cell lines. The combination treatment of GW4869 or Nexinhib20 effectively enhanced the inhibitory effects of first-line chemotherapy on the SCLC cells. Furthermore, we demonstrated that reducing exosome release through GW4869 and Nexinhib20 treatment effectively reduced cellular proliferation and significantly induced apoptosis in SCLC cells. Also, we showed that combining exosome inhibition with chemotherapy has a significant synergistic effect on cellular proliferation. We also found increased p53 and p21 expressions with western blot and significantly changing Bax, BCL2, caspase-3 and caspase-9 expressions. Inhibiting the exosome pathway offers opportunities for developing novel, effective treatment strategies for SCLC.

Blockade of exosome release alleviates the hypersensitive reaction by influencing the T helper cell population in cow's milk allergic mice.

The aim of this work was to evaluate the ameliorative effects of exosome biogenesis in cow's milk allergy (CMA) response. In this context, BALB/c mice were systemically sensitized with cow's milk proteins plus an aluminum adjuvant to induce CMA. The inhibitor GW4869 of exosome biogenesis was added before sensitization and then the anaphylactic reactions were evaluated both in vivo (clinical score and body temperature) and in vitro (serum histamine, allergen-specific antibodies, cytokines by ELISA and cell analysis by flow cytometry) to explore the role of exosomes in the development of CMA. Nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM) showed that the size distribution and morphology of CMA-derived exosomes were not changed after GW4869 preconditioning, and the concentration of exosomes was much lower than that of the CMA group. In the GW4869 group, inhibition of release of exosomes modulated the induction of T helper 2 cell (Th2)-related substances, with a decrease in histamine and allergen-specific immunoglobulin (Ig) E, and the expression of Th1, Th2, and Th17 cells all decreased as well. Moreover, the experimental data were integrated by means of principal component analysis (PCA) to give an overview that the percentage of Th cells and concentrations of cytokines were more influenced by GW4869 treatment. These data for the first time demonstrated that exosomes are involved in the development of CMA and the blockade of exosome release with GW4869 suppressed the IgE-mediated immune response in CMA.

GTS-21 attenuates ACE/ACE2 ratio and glycocalyx shedding in lipopolysaccharide-induced acute lung injury by targeting macrophage polarization derived ADAM-17.

Acute lung injury (ALI) has received considerable attention in intensive care owing to its high mortality rate. It has been demonstrated that the selective alpha7 nicotinic acetylcholine receptor agonist Gainesville Tokushima scientists (GTS)-21 is promising for treating ALI caused by lipopolysaccharides (LPS). However, the precise underlying mechanism remains unknown. This study aimed to investigate the potential efficacy of GTS-21 in the treatment of ALI. We developed mouse models of ALI and alveolar epithelial type II cells (AT2s) injury following treatment with LPS and different polarized macrophage supernatants, respectively. Pathological changes, pulmonary edema, and lung compliance were assessed. Inflammatory cells count, protein content, and pro-inflammatory cytokine levels were analysed in the bronchoalveolar lavage fluid. The expression of angiotensin-converting enzyme (ACE), ACE2, syndecan-1 (SDC-1), heparan sulphate (HS), heparanase (HPA), exostosin (EXT)-1, and NF-κB were tested in lung tissues and cells. GTS-21-induced changes in macrophage polarization were verified in vivo and in vitro. Polarized macrophage supernatants with or without recombination a disintegrin and metalloproteinase-17 (ADAM-17) and small interfering (si)RNA ADAM-17 were used to verify the role of ADAM-17 in AT2 injury. By reducing pathological alterations, lung permeability, inflammatory response, ACE/ACE2 ratio, and glycocalyx shedding, as well as by downregulating the HPA and NF-κB pathways and upregulating EXT1 expression in vivo, GTS-21 significantly diminished LPS-induced ALI compared to that of the LPS group. GTS-21 significantly attenuated macrophage M1 polarization and augmented M2 polarization in vitro and in vivo. The destructive effects of M1 polarization supernatant can be inhibited by GTS-21 and siRNA ADAM-17. GTS-21 exerted a protective effect against LPS-induced ALI, which was reversed by recombinant ADAM-17. Collectively, GTS-21 alleviates LPS-induced ALI by attenuating AT2s ACE/ACE2 ratio and glycocalyx shedding through the inhibition of macrophage M1 polarization derived ADAM-17.

Novel mechanism of cisplatin resistance in head and neck squamous cell carcinoma involving extracellular vesicles and a copper transporter system.

BACKGROUND: Cisplatin (CDDP) plays a central role in chemotherapy for head and neck squamous cell carcinoma (HNSCC), but drug resistance in HNSCC chemotherapy remains a problem, and the mechanism of CDDP resistance is unclear. We investigated CDDP-resistance mechanisms mediated by extracellular vesicles (EVs) and ATPase copper transporting beta (ATP7B) in HNSCC. METHODS: We established CDDP-resistant sublines of HNSCC cells and verified their ATP7B expression. We used an EV secretion inhibitor (GW4869) and ATP7B short hairpin (sh)RNA transfection to examine the correlation between EV secretion and ATP7B expression. RESULTS: The CDDP-resistant HNSCC sublines showed decreased CDDP sensitivity and increased ATP7B expression. GW4869 suppressed ATP7B expression, and ATP7B shRNA transfection suppressed EV secretion. The suppressions of EV secretion and ATP7B expression both enhanced CDDP's cell-killing effect. CONCLUSIONS: EVs were involved in the ATP7B-mediated mechanism underlying CDDP resistance. Further clarification of the EV-induced CDDP-resistance mechanism may lead to novel therapeutic strategies for HNSCC.

Mechanism of HCG regulating epithelial-mesenchymal transition progression in endometrial cells through the FoxO1/miR223-5p/Wnt5α pathway.

RESEARCH QUESTION: Does human chorionic gonadotrophin (HCG) influence endometrial receptivity and epithelial-mesenchymal transition (EMT) via the FoxO1/miR223-5p/Wnt5α pathway? DESIGN: This study aimed to establish the co-culture system of human embryonic trophoblast cell line (HTR-8-Svneo) cells and human endometrial epithelial cell line (HEEC) cells. The expression of Wnt5α protein and EMT-related proteins in HTR-8-Svneo and HEEC cells treated in a gradient-dependent manner using HCG and exosome inhibitor GW4869 were detected in the co-culture system. RESULTS: In the HTR-8-Svneo/HEEC co-culture system, miR223-5p in HEEC cells increased significantly with induction of HTR-8-Svneo cells by 100 IU/ml HCG for 48 h (P = 0.046), and Wnt5α protein decreased significantly in HEEC cells (P = 0.021). Pretreatment of HTR-8-Svneo cells with GW4869, and knockdown of FoxO1 in HTR-8-Svneo cells, significantly inhibited the above effects of HCG on miR223-5p and Wnt5α expression in HEEC cells in the HTR-8-Svneo/HEEC co-culture system. HTR-8-Svneo cells induced with 100 IU/ml HCG for 48 h significantly enhanced the logarithmic phase proliferation activity of HEEC cells in the co-culture system (P < 0.001), while knockdown of FoxO1 in HTR-8-Svneo cells and inhibition of miR223-5p in HEEC cells suppressed proliferation of HEEC cells in the HTR-8-Svneo/HEEC co-culture system (P < 0.001). CONCLUSIONS: HCG exposure induces HTR-8-Svneo cells to up-regulate miR223-5p expression, which enters HEEC cells in the co-culture system through the exosomal pathway, and inhibits Wnt5α expression and the progress of EMT.

Helicobacter pylori promotes gastric fibroblast proliferation and migration by expulsing exosomal miR-124-3p.

Gastric fibroblasts (GFs) are direct targets of Helicobacter pylori (H. pylori). GFs infected with H. pylori exhibit marked changes in their morphology and biological behavior. However, the molecular mechanisms by which H. pylori regulates GFs remain unknown. In this study, we cocultured GFs with H. pylori for 48 h. As a result, GFs exhibited an elongated and spindle-shaped morphology. Further, cancer-associated fibroblast (CAF) biomarkers were increased, and related behaviors were significantly enhanced in H. pylori-activated GFs. The number of extracellular vesicles (EVs) secreted by H. pylori-activated GFs remarkably increased. The miR-124-3p level was increased in secreted EVs but decreased in the cytoplasm of H. pylori-activated GFs. Overexpression of miRNA-124-3p in the original GFs significantly suppressed their proliferation and migration. In addition, the migration-promoting effects of H. pylori-activated GFs were suppressed by miR-124-3p and GW4869, which blocked EV generation. Finally, pull-down and luciferase assays revealed that SNAI2 is a target of miR-124-3p. The migration-inhibitory effects of GFs treated with miR-124-3p were eliminated by the overexpression of SNAI2, and the upregulation of SNAI2 in H. pylori-activated GFs was partially alleviated by miR-124-3p or GW4869. Overall, H. pylori infection promotes the proliferation and migration of GFs by accelerating the expulsion of EVs carrying miRNA-124-3p, a SNAI2 inhibitor.

A novel multi-functional fluorescent probe for dual-channel detection of SO2 and Hg2+ and dynamic visualization of SO2 fluctuations in vivo upon mercury exposure.

Although there are many drugs used for the treatment of mercury poisoning, it is remains confused that pathological symptoms associated with Hg2+-induced oxidative stress. It is reported that SO2 can be generated as the anti-oxidant, and plays an important role in maintaining redox balance in cells. There has not yet been a study to precisely track the changes in SO2 during mercury ion poisoning. We developed a novel dual-response fluorescence probe (CY-SPH) for respective or successive determination of Hg2+ and SO2 in neutral aqueous media. The nucleophilic addition of HSO3- toward CY-SPH caused a significant fluorescence enhancement at 455 nm while the Hg2+ -triggered desulfurization of CY-SPH to the final phenolic product (CY-OH) elicited a markedly enhanced emission at 760 nm, allowing for two-color visualization of Hg2+ and SO2 with good selectivity (detection limit: 67.2 nM for Hg2+ and 34.7 nM for SO2). Moreover, CY-OH could undergo further nucleophilic addition reaction with HSO3- and resulted in a decrease in emission at 760 nm and an increase in emission at 438 nm, enabling the ratiometric determination of SO2 with better sensitivity (detection limit, 3.50 nM). Significantly, CY-SPH can monitor the endogenous SO2 fluctuations upon mercury exposure by means of confocal fluorescence imaging, which may prove valuable for deciphering the relationship between SO2 levels and the mercury induced oxidative stress. We anticipated that this research will promote to understand the functions of SO2 under the oxidative stress by Hg2+.

Chemical element distribution in Arctic soils: Assessing vertical, spatial, animal and anthropogenic influences in Elsa and Ebba Valleys, Spitsbergen, Svalbard.

The Arctic region is threatened by climate change and pollution caused by human activities which potentially influence the elemental concentrations available to and from the biota. To better understand this delicate balance, it is crucial to investigate the role of several factors. Therefore, we quantified the level of 43 chemical elements in soils from Elsa and Ebba Valleys, Petunia Bay, Spitsbergen, a region that has experienced lasting environmental impacts from historical mining activities. We evaluated the a) vertical sampling influence by examining the variation in element distribution between the soil upper and deeper layers, b) animal influence by verifying the role of native animals, particularly vertebrates, in introducing thought faeces elements to the soil and c) anthropogenic influence by studying the spatial geographical differences in element distribution based on the degree of human pressure between the valleys. Our analysis also includes data on soil organic matter (SOM) and mineral composition. Both valleys exhibited similar mineralogical composition, but Elsa Valley had higher concentrations of most analyzed elements compared to Ebba Valley. Despite the contribution of vertebrate feaces, no increase in element concentrations was observed in the animal-influenced soils. The sampled soil layers had similar chemical element profiles for most elements. SOM content tended to be higher in superficial soils and showed a strong positive correlation with most quantified elements. The higher concentrations in Elsa Valley reflect its past mining and mineral exploration, making this area more significantly impacted than Ebba Valley. Surprisingly, vertebrate animals do not appear to influence the concentrations of chemical elements or organic matter in soils. Our findings provide valuable insights into the legacy of past mining activities and mechanisms driving environmental change in the Arctic.

Design, Synthesis, In Silico and POM Studies for the Identification of the Pharmacophore Sites of Benzylidene Derivatives.

Due to the uneven distribution of glycosidase enzyme expression across bacteria and fungi, glycoside derivatives of antimicrobial compounds provide prospective and promising antimicrobial materials. Therefore, herein, we report the synthesis and characterization of six novel methyl 4,6-O-benzylidene-α-d-glucopyranoside (MBG) derivatives (2-7). The structures were ascertained using spectroscopic techniques and elemental analyses. Antimicrobial tests (zone of inhibition, MIC and MBC) were carried out to determine their ability to inhibit the growth of different Gram-positive, Gram-negative bacteria and fungi. The highest antibacterial activity was recorded with compounds 4, 5, 6 and 7. The compounds with the most significant antifungal efficacy were 4, 5, 6 and 7. Based on the prediction of activity spectra for substances (PASS), compounds 4 and 7 have promising antimicrobial capacity. Molecular docking studies focused on fungal and bacterial proteins where derivatives 3 and 6 exhibited strong binding affinities. The molecular dynamics study revealed that the complexes formed by these derivatives with the proteins L,D-transpeptidase Ykud and endoglucanase from Aspergillus niger remained stable, both over time and in physiological conditions. Structure-activity relationships, including in vitro and in silico results, revealed that the acyl chains [lauroyl-(CH3(CH2)10CO-), cinnamoyl-(C6H5CH=CHCO-)], in combination with sugar, were found to have the most potential against human and fungal pathogens. Synthetic, antimicrobial and pharmacokinetic studies revealed that MBG derivatives have good potential for antimicrobial activity, developing a therapeutic target for bacteria and fungi. Furthermore, the Petra/Osiris/Molinspiration (POM) study clearly indicated the presence of an important (O1δ-----O2δ-) antifungal pharmacophore site. This site can also be explored as a potential antiviral moiety.

Synthesis of benzylidene-benzofuranone derivatives as probes for detection of amyloid fibrils in cells.

Aggregated protein is the common cause of a wide variety of neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease, etc. It is proven that protein aggregation like amyloid ß (Aß) is one of the critical factors causing AD and, its diagnosis in the early stages of the disease is important for the treatment or prevention of AD. To have a better understanding of protein aggregation and its pathologies, there is a huge need to design and develop new and more trustworthy probe molecules for in vitro amyloid quantification and in vivo amyloid imaging. In this study, 17 new biomarker compounds, have been synthesized from benzofuranone derivatives, to detect and identify amyloid in vitro (dye-binding assay) as well as in the cell by staining method. According to the results, some of these synthetic derivatives can be considered suitable identifiers and quantifiers to detect amyloid fibrils in vitro. Compared to thioflavin T, 4 probes out of 17 probes have shown good results in selectivity and detectability of Aß depositions, and their binding properties were also confirmed with in silico analysis. The drug-likeness prediction results for selected compounds by the Swiss ADME server show a satisfactory percentage of blood-brain barrier (BBB) permeability and gastrointestinal (GI) absorption. Among all of them, compound 10 was able to show better binding properties than others, and in vivo study showed that this compound was capable of detecting intracellular amyloid.Communicated by Ramaswamy H. Sarma.

Synthesis of benzylidene-indandione derivatives as quantification of amyloid fibrils.

The formation of amyloid fibrils due to its association with fatal diseases, including Alzheimer's, has been investigated by many researchers. These common diseases, mostly become verified when it is too late to be treated. Currently, no cure is available for neurodegenerative diseases, and the process of diagnosing amyloid fibrils in the early stages, while there are fewer amyloid fibrils, has become an issue of interest. To do so, determining new probes with the highest binding affinity to the lowest number of amyloid fibrils is necessary. In this study, we proposed to employ new synthesized benzylidene-indandione derivatives as amyloid fibrils fluorescent detection probes. Native soluble proteins of insulin, bovine serum albumin (BSA), BSA amorphous aggregation, and insulin amyloid fibrils were used to evaluate our compounds' specificity to the amyloid structure. While ten synthesized compounds were examined individually, four of them including 3d, 3g, 3i, and 3j showed a high binding affinity with selectivity and specificity to amyloid fibrils, and their binding properties were also confirmed with in silico analysis. The drug-likeness prediction results for selected compounds by Swiss ADME server shows a satisfactory percentage of blood-brain barrier (BBB) permeability and gastrointestinal (GI) absorption for the compounds 3g, 3i, and 3j. More evaluation is needed to determine all properties of compounds in vitro and in vivo.

Structural, vibrational spectroscopy, molecular docking, DFT studies and antibacterial activity of (E)-N1-(3-chlorobenzylidene)benzene-1,4-diamine.

In this work, (E)-N1-(3-chlorobenzylidene)benzene-1,4-diamine (CBD) compound was synthesized with good yield. The spectral studies were recorded by FT-IR, FT-Raman, NMR and UV-Vis to determine structural parameters. The geometrical parameters were optimized using DFT calculations at 6-311++G(d,p) basis set. The calculated structural parameters of the molecule were in line with the experimental data. The molecular orbitals of the compound were investigated through highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) analysis. The hyper conjugative interaction energy E(2) along with donor, acceptor electron densities (EDs) were determined by natural bond orbital (NBO) analysis. The molecular electrostatic potential (MEP), mulliken atomic charges, non-linear optical (NLO) properties and potential energy surface (PES) scan were also calculated. The 1H and 13C NMR chemical shifts calculated using Gauge invariant atomic orbital (GIAO) method were compared with the experimental NMR chemical shifts. Thermogravimetry (TG) and Differential Scanning Calorimetry (DSC) were carried out to characterise the thermal behaviour and stability of CBD molecule. In addition, PreADMET tool was also used to estimate ADME and Toxicity of CBD compound. The compound screened against four pathogens two gram positive and two gram negative had shown good anti-bacterial behaviour. The molecular docking studies executed against anti-bacterial target topoisomerase DNA gyrase enzyme (2XCT) emphasized good binding behaviour over the standard drug.Communicated by Ramaswamy H. Sarma.

Design, Synthesis, Crystal Structure, In Vitro and In Silico Evaluation of New N'-Benzylidene-4-tert-butylbenzohydrazide Derivatives as Potent Urease Inhibitors.

BACKGROUND: Hydrazides play a vital role in making biologically active compounds in various fields of chemistry. These determine antioxidant, antidepressant, antimalarial, anti-inflammatory, antiglycating, and antimicrobial activity. In the present study, twenty-three new N' benzylidene-4-(tert-butyl)benzohydrazide derivatives (4-26) were synthesized by the condensation of aromatic aldehydes and commercially available 4-(tert-butyl)benzoic acid. All the target compounds were successfully synthesized from good to excellent yield; all synthesized derivatives were characterized via spectroscopic techniques such as HREI-MS and 1H-NMR. Synthesized compounds were evaluated for in vitro urease inhibition. All synthesized derivatives demonstrated good inhibitory activities in the range of IC50 = 13.33 ± 0.58-251.74 ± 6.82 µM as compared with standard thiourea having IC50 = 21.14 ± 0.425 µM. Two compounds, 6 and 25, were found to be more active than standard. SAR revealed that electron donating groups in phenyl ring have more influence on enzyme inhibition. However, to gain insight into the participation of different substituents in synthesized derivatives on the binding interactions with urease enzyme, in silico (computer simulation) molecular modeling analysis was carried out.

Synthesis, Characterization, and Investigation of Mesomorphic Properties of a New 2,5-Bis-(4-alkanoyloxybenzylidene)cyclopentan-1-one.

A new set of cyclopentanone chalcone esters 2,5-bis-(4-alkanoyloxybenzylidene)cyclopentan-1-one (B2-B10) has been synthesized and monitored by TLC. Structures of these compounds were determined by spectroscopic techniques (FTIR, H NMR, and mass spectrometry). Differential scanning calorimetry (DSC) and polarized optical microscopy were used to evaluate their transition temperatures and mesophase properties (POM) throughout heating and cooling scans. The thermal data indicate that the compounds B5-B10 have mesomorphic properties with thermal stabilities; the data also reveal that the compounds B6-B10 are monotropic, whereas B5 is enantiotropic. B6, B7, and B9 only have a nematic phase, but B8 and B10 have a smectic phase followed by a nematic phase, and B5 only has a smectic phase. In addition, the study reveals that the inclusion of an acyl group as a terminal chain had the opposite effect on isotropization temperatures for compounds B6, B8, and B10, resulting in an increase in transition temperatures and a decrease in mesophase stability. The lack of a smectic phase in B7 and B9 compounds could be attributed to the narrow phase temperature range, which makes examination difficult, or to the molecules' lack of lateral attraction.

Photoprotective effect of 18ß-glycyrrhetinic acid derivatives against ultra violet (UV)-B-Induced skin aging.

Excessive exposure to sun can harm the skin, causing sunburn, photo-aging, and even skin cancer. Different benzylidene derivatives (A02-A18 and A19-A34) of 18ß-Glycyrrhetinic acid (A01) were designed and synthesized in an effort to discover photo-protective compounds against UV-B -induced skin aging. The synthesized derivatives were subjected to cellular viability test using MTT assay in primary Human Dermal Fibroblasts (HDFs). The results indicate A01, A05, A15, A22, A23, A25, A26, A28, A29, A32, A33, and A34 significantly enhanced cell viability of HDFs. Compound A33 at 10 and 25 µM showed a significant photo-protective effect against UV-B (10 mJ/cm2) -induced damage in HDFs. A33 at 25 µM significantly restored the UV-B -induced damage via its potent anti-oxidant, anti-apoptotic effects and ability to prevent collagen degradation. These findings pave the way for further development of A33 as a photo-protective skin agent.

Exporting Proteins Associated with Senescence Repair via Extracellular Vesicles May Be Associated with Early Pregnancy Loss.

INTRODUCTION: Dysfunction of placental development is involved in early pregnancy loss. Senescent changes have been seen in missed miscarriage, one type of pregnancy loss. Extracellular vesicles (EVs) have been widely implicated in the pathogenesis of diseases. In this study, we investigated the protein profiles in placental EVs derived from missed miscarriage in comparison with healthy pregnancy. We also investigated whether cargos packed into EVs are involved in the dysfunctional development of the placenta seen in missed miscarriage. METHODS: Proteomic analysis of placental EVs derived from healthy and missed-miscarriage placentae was performed. Three senescence-repair-associated proteins, replication protein A-70 (RPA-70), proteasome activator subunit-4 (PMSE-4), and protein activated kinase-2, (PAK-2) were examined in placental EVs and placentae, and in placental explants that had been treated with or without GW4869, by western blotting and immunohistochemistry. RESULTS: The total number of proteins associated with placental EVs was not different between the two groups. However, there were 106 and 151 abundantly expressed proteins associated with placental micro- or nano-EVs from missed miscarriage in comparison with EVs from controls. Of these abundant proteins, 59 and 81 proteins in placental micro- or nano-EVs, respectively, are associated with DNA damage/repair and cell death/survival. We further found higher levels of three senescence-repair-associated proteins (RPA-70, PMSE-4, and PAK-2) associated with placental EVs, but lower levels of these proteins in missed-miscarriage placentae. Regarding inhibition of EV formation or release by GW4869, we found that the expression of these three proteins was higher in GW4869-treated placental explants from missed miscarriage. DISCUSSION: Our data may suggest that "inadvertently" sorting of cargos and exporting proteins associated with senescence-repair by placental EVs may be associated with the dysfunction of placental development seen in missed miscarriage.

From Hair to Colon: Hair Follicle-Derived MSCs Alleviate Pyroptosis in DSS-Induced Ulcerative Colitis by Releasing Exosomes in a Paracrine Manner.

Ulcerative colitis (UC) has attracted intense attention due to its high recurrence rate and the difficulty of treatment. Pyroptosis has been suggested to be crucial in the development of UC. Although mesenchymal stem cells (MSCs) are broadly used for UC therapy, they have rarely been studied in the context of UC pyroptosis. Hair follicle-derived MSCs (HFMSCs) are especially understudied with regard to UC and pyroptosis. In this study, we aimed to discover the effects and potential mechanisms of HFMSCs in UC. We administered HFMSCs to dextran sulfate sodium- (DSS-) treated mice and found that the HFMSCs significantly inhibited pyroptosis to alleviate DSS-induced UC. A transwell system and GW4869, an exosome inhibitor, were used to prove the paracrine mechanism of HFMSCs. HFMSC supernatant reduced pyroptosis-related protein expression and promoted cell viability, but these effects were attenuated by GW4869, suggesting a role for HFMSC-released exosomes (Exos) in pyroptosis. Next, Exos were extracted and administered in vitro and in vivo to explore their roles in pyroptosis and UC. In addition, the biodistribution of Exos in mice was tracked using an imaging system and immunofluorescence. The results suggested that Exos not only improved DSS-induced pyroptosis and UC but also were internalized into the injured colon. Furthermore, the therapeutic efficacy of Exos was dose dependent. Among the Exo treatments, administration of 400 µg of Exos per mouse twice a week exhibited the highest efficacy. The differentially expressed miRNAs (DEmiRNAs) between MSCs and MSC-released Exos suggested that Exos might inhibit pyroptosis through tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) signalling and interferon- (IFN-) gamma pathways. Our study reveals that HFMSCs can alleviate pyroptosis in UC by releasing DEmiRNA-containing Exos in a paracrine manner. This finding may lead to new treatments for UC.

Synthesis of 4-Hydroxyquinolines as Potential Cytotoxic Agents.

The synthesis of alkyl 2-(4-hydroxyquinolin-2-yl) acetates and 1-phenyl-4-(phenylamino)pyridine-2,6(1H,3H)-dione was optimised. Starting from 4-hydroxyquinolines (4HQs), aminomethylation was carried out via the modified Mannich reaction (mMr) applying formaldehyde and piperidine, but a second paraformaldehyde molecule was incorporated into the Mannich product. The reaction also afforded the formation of bisquinoline derivatives. A new 1H-azeto [1,2-a]quinoline derivative was synthesised in two different ways; namely starting from the aminomethylated product or from the ester-hydrolysed 4HQ. When the aldehyde component was replaced with aromatic aldehydes, Knoevenagel condensation took place affording the formation of the corresponding benzylidene derivatives, with the concomitant generation of bisquinolines. The reactivity of salicylaldehyde and hydroxynaphthaldehydes was tested; under these conditions, partially saturated lactones were formed through spontaneous ring closure. The activity of the derivatives was assessed using doxorubicin-sensitive and -resistant colon adenocarcinoma cell lines and normal human fibroblasts. Some derivatives possessed selective toxicity towards resistant cancer cells compared to doxorubicin-sensitive cancer cells and normal fibroblasts. Cytotoxic activity of the benzylidene derivatives and the corresponding Hammett-Brown substituent were correlated.

The alpha-7 nicotinic acetylcholine receptor agonist GTS-21 does not affect food intake in rats.

Obesity is a prevalent disease, but effective treatments remain limited. Agonists of the alpha-7 nicotinic acetylcholine receptor (α7nAChR) promote negative energy balance in mice, but these effects are not well-studied in rats. We tested the hypothesis that the α7nAChR agonist GTS-21 would decrease food intake and body weight in adult male Sprague Dawley rats. Contrary to our hypothesis, acute systemic administration of GTS-21 produced no significant effects on chow or high-fat diet (HFD) intake. Acute intracerebroventricular (ICV) GTS-21 also had no impact on chow intake, and actually increased body weight at the highest dose tested. Previous studies suggest that GTS-21 engages the food intake-suppressive glucagon-like peptide-1 (GLP-1) system in mice. As there are known species differences in GLP-1 physiology between mice and rats, we tested the ability of GTS-21 to elicit GLP-1 secretion in rats. Our results showed that plasma levels of total GLP-1 in rats were not significantly altered by peripheral GTS-21 injection. These results represent an advance in understanding how α7nAChR activation impacts energy balance control in rodents and suggest that there may be important differences between rats and mice in the ability of GTS-21/α7nAChR activation to increase secretion of GLP-1.