Asp-containing actinomycin and tetracyclic chromophoric analogues from the Streptomyces sp. strain S22.

Three novel actinomycins, actimomycin S (1), neo-actinomycins C and D (2 and 3), and one new benzo[d]oxazole alkaloid (4) were isolated from the Streptomyces sp. strain S22, along with three known congeners F9 (5), X2 (6) and X0ß (7) and 2-acetylamino-3-hydroxyl-4-methyl-benzoic acid methyl ester (8). The structures of the new products were elucidated by spectroscopic methods, and the absolute configuration of amino acid residues was determined by Marfey's analysis. Actinomycin S contains an aspartic acid (Asp) residue in the ß-peptidolactone ring. This is the first report of an Asp residue within an actinomycin-type natural product. Notably, neo-actinomycins C and D feature a rare tetracyclic 5H-oxazolo[4,5-b]phenoxazine chromophore. Among these, neo-actinomycin D, with an unprecedented molecular formula, represents the highest molecular weight member in the actinomycin family. Actinomycins 1-3 exhibited antimicrobial activity against multiple resistant "ESKAPE" pathogens with MIC values ranging from 1.25 to 80.0 µg mL-1. In addition, 1-3 showed potent cytotoxic activities against the HepG2 liver carcinoma cell line with IC50 values of 0.10, 0.32, and 0.024 µM, respectively. Furthermore, 1 inhibited cell proliferation by inducing G0-G1 phase arrest in the cell cycle.

Extracellular Vesicles Derived from a Human Brain Endothelial Cell Line Increase Cellular ATP Levels.

Engineered cell-derived extracellular vesicles (EVs) such as exosomes and microvesicles hold immense potential as safe and efficient drug carriers due to their lower immunogenicity and inherent homing capabilities to target cells. In addition to innate vesicular cargo such as lipids, proteins, and nucleic acids, EVs are also known to contain functional mitochondria/mitochondrial DNA that can be transferred to recipient cells to increase cellular bioenergetics. In this proof-of-concept study, we isolated naïve EVs and engineered EVs loaded with an exogenous plasmid DNA encoding for brain-derived neurotrophic factor (BDNF-EVs) from hCMEC/D3, a human brain endothelial cell line, and RAW 264.7 macrophages. We tested whether mitochondrial components in naïve or engineered EVs can increase ATP levels in the recipient brain endothelial cells. EVs (e.g., exosomes and microvesicles; EXOs and MVs) were isolated from the conditioned medium of either untreated (naïve) or pDNA-transfected (Luc-DNA or BDNF-DNA) cells using a differential centrifugation method. RAW 264.7 cell line-derived EVs showed a significantly higher DNA loading and increased luciferase expression in the recipient hCMEC/D3 cells at 72 h compared with hCMEC/D3 cell line-derived EVs. Naïve EVs from hCMEC/D3 cells and BDNF-EVs from RAW 264.7 cells showed a small, but a significantly greater increase in the ATP levels of recipient hCMEC/D3 cells at 24 and 48 h post-exposure. In summary, we have demonstrated (1) differences in exogenous pDNA loading into EVs as a function of cell type using brain endothelial and macrophage cell lines and (2) EV-mediated increases in the intracellular ATP levels in the recipient hCMEC/D3 monolayers.

[Differentially expressed microRNAs in the testis of male rats exposed to cigarette smoke: Screening and function verification].

OBJECTIVE: To screen differentially expressed miRNAs in the testis of male rats exposed to cigarette smoke (CS) and identify the early molecular markers of CS-induced apoptosis of testicular cells. METHODS: We randomly divided 200 SPF male SD rats into blank control and low-dose (10 non-filter cigarettes/d), medium-dose (20 non-filter cigarettes/d) and high-dose (30 non-filter cigarettes/d) CS exposure groups. After 2, 4, 6, 8 and 12 weeks of CS exposure, we observed the histopathological changes of the testis by HE staining, detected the apoptosis of the testicular cells by TUNEL, and determined the expressions of caspase-3 and caspase-9 in the testis tissue by immunohistochemistry, RT-PCR and Western blot. Based on the laboratory results, we selected 4 testicular samples from the 12-week high-dose group and another 4 from the control for miRNA microarray-based screening, bioinformatics analysis, and verification of differentially expressed miRNAs in all the animals by RT-PCR. RESULTS: Compared with the controls, the CS-exposed rats showed dose- and time-dependent increase in the atrophy of the testis and significantly increased number of apoptotic testis cells from the 6th week of exposure (P < 0.05), with dramatically up-regulated expressions of caspase-3 (P < 0.01) and caspase-9 protein and mRNA (P < 0.05) in the testis tissue. Microarray-based screening and RT-PCR revealed 5 differentially expressed miRNAs in the testis of the CS-exposed rats, of which miR-138-5p, miR-181d-5p, miR-19a-3p and miR-3588 were down-regulated, and miR-155-5p up-regulated, and the target genes of the differentially expressed miRNAs positively regulated the apoptosis of the testicular cells. CONCLUSIONS: The differentially expressed miRNAs miR-155-5p, miR-138-5p, miR-181d-5p, miR-19a-3p and miR-3588 regulate CS-induced apoptosis of testicular cells, and may become biomarkers for early diagnosis and prognosis of CS-induced spermatogenesis obstruction.《.

Alterations in Oscillatory Behavior of Central Medial Thalamic Neurons Demonstrate a Key Role of CaV3.1 Isoform of T-Channels During Isoflurane-Induced Anesthesia.

Although the central medial nucleus (CeM) of the thalamus is an essential part of the arousal system for sleep and anesthesia initiation, the precise mechanisms that regulate its activity are not well studied. We examined the role of CaV3.1 isoform of T-type calcium channels (T-channels) in the excitability and rhythmic activity of CeM neurons during isoflurane (ISO)-induced anesthesia by using mouse genetics and selective pharmacology. Patch-clamp recordings taken from acute brain slices revealed that CaV3.1 channels in CeM are inhibited by prototypical volatile anesthetic ISO (250 and 500 µM) and selective T-channels blocker 3,5-dichloro-N-[1-(2,2-dimethyl-tetrahydro-pyran-4-ylmethyl)-4-fluoro-piperidin-4-ylmethyl]-benzamide (TTA-P2). Both TTA-P2 and ISO attenuated tonic and burst firing modes, and hyperpolarized CeM neurons from wild type (WT) mice. These effects were greatly diminished or abolished in CaV3.1 null mice. Our ensuing in vivo local field potential (LFP) recordings from CeM indicated that the ability of TTA-P2 and anesthetic concentrations of ISO to promote δ oscillation was substantially weakened in CaV3.1 null mice. Furthermore, escalating ISO concentrations induced stronger burst-suppression LFP pattern in mutant than in WT mice. Our results demonstrate for the first time the importance of CaV3.1 channels in thalamocortical oscillations from the non-specific thalamic nuclei that underlie clinically important effects of ISO.

Dual mediating effects of social support and fertility stress on mindfulness and fertility quality of life in infertile men: A case-control study.

Background: Infertility is one of the three major public health problems in the world, bringing immense physical and psychological damage to men and affecting the quality of men's fertility life. Thus, the purpose of this study was to analyze the status of social support, fertility stress, mindfulness, and fertility quality of life in infertile men, and to explore the dual mediating effects of social support and fertility stress on mindfulness and fertility quality. Methods: A case-control group study was conducted, with 246 men in the case group and 149 in the control group. The Social Support Scale, Fertility Stress Scale, Mindfulness Scale, and Fertility Quality of Life Scale were used to establish a structural equation model using Mplus 8.3 to explore social support and fertility stress. Pathway relationships were drawn between mindfulness and fertility quality of life in infertile men. Results: There were significant differences between infertile and healthy men in each dimension of the core module of fertility quality of life, in the total score of the treatment module, in the total score of social support, in subjective and objective support, and in the total score of fertility stress, social pressure, sexual pressure, marital relationship, and childless pressure (p < 0.05 in each case). Further, the fertility quality of life in infertile men was positively correlated with mindfulness and social support, and negatively correlated with fertility stress (p < 0.05); mindfulness could directly affect the core and treatment modules of fertility life quality, and indirectly affect the core of fertility life quality through social support (mediation effect accounted for 19.0%), while the treatment module (mediation effect accounted for 13.7%), and the core module indirectly affected fertility life quality through fertility stress (mediation effect accounted for 16.8%). Conclusion: The fertility quality of life of infertile men is not optimistic. Mindfulness-related interventions and programs can improve their fertility quality of life.

Structural Identification of Zotarolimus (ABT-578) Metabolites Generated by Human Liver Microsomes Using Ion-Trap and High-Resolution Time-of-Flight Mass Spectrometry in Combination with the Analysis of Fragmentation Patterns.

Zotarolimus (ABT-578) is a sirolimus derivative that, like sirolimus and everolimus, is an inhibitor of cell growth via inhibition of the mechanistic target of rapamycin (mTOR). Zotarolimus was developed for coating coronary stents to prevent smooth muscle cell proliferation and restenosis. Albeit zotarolimus-eluting cardiovascular devices have been on the market for years, details of zotarolimus drug metabolism in humans are still unknown. Hence, it was the goal of the present study to identify zotarolimus metabolites generated by incubation with human liver microsomes. Metabolite structures were identified using high-resolution mass spectrometry, MS/ion-trap (MSn), and comparison of fragmentation patterns of the metabolites with those of zotarolimus and other known sirolimus derivatives. Kinetic parameters such as incubation time, human liver microsomal protein concentrations, and drug concentrations were optimized before scaling up the metabolism experiments. Human liver microsomes mainly hydroxylated and/or demethylated zotarolimus. The structures of the following metabolites were identified: O-demethylated metabolites: 39-O-desmethyl, 16-O-desmethyl, and 27-O-desmethyl zotarolimus; hydroxylated metabolites: hydroxy piperidine zotarolimus, 11-hydroxy, 12-hydroxy, 14-hydroxy, 23-hydroxy, 24-hydroxy, 25-hydroxy, 45/46-hydroxy, and 49-hydroxy zotarolimus; demethylated-hydroxylated metabolites: 16-O-desmethyl, 23/24-hydroxy; 39-O-desmethyl, 23/24-hydroxy; 39-O-desmethyl, 25-hydroxy zotarolimus; 39-O-desmethyl, 11-hydroxy zotarolimus; 39-O-desmethyl, hydroxy-piperidine zotarolimus; 27-O-desmethyl, 45/46-hydroxy zotarolimus; didemethylated metabolites: 16,39-O-didesmethyl zotarolimus; 16,27-O-didesmethyl zotarolimus; 27,39-O-didesmethyl zotarolimus; and dihydroxylated metabolites: 11,24-dihydroxy zotarolimus, 12,24-dihydroxy zotarolimus, and 11,47/48-dihydroxy zotarolimus. It is concluded that zotarolimus is extensively metabolized by human liver microsomes. Twenty-four of these metabolites could be structurally identified using a combination of ion-trap MSn and high-resolution mass spectrometry.

A qualitative analysis of control-value appraisals, positive achievement emotions, and EFL performance in a Chinese senior high school context.

Based on the control-value theory (CVT), this study qualitatively investigated the relationship between control-value appraisals, achievement emotions (mainly enjoyment, pride, and hope), and English-as-a-foreign-language (EFL) performance, and explored other antecedents of achievement emotions in addition to control-value appraisals. Data were collected from six Chinese high school students through two semi-structured interviews and one focus group discussion. With thematic analysis, data were analyzed under the framework of the CVT using NVivo 11.0. Results indicate that high perceived control, high perceived extrinsic, and intrinsic values were interactively associated with enjoyment, pride, and hope. Low perceived control, high perceived extrinsic value, and low perceived intrinsic value were interactively associated with fewer positive achievement emotions (only hope) and more negative achievement emotions like fear. High perceived control, high perceived extrinsic value, and low perceived intrinsic value were interactively associated with fewer positive achievement emotions (only pride), and more negative achievement emotions like anguish. Besides, positive achievement emotions were positively associated with EFL performance, while negative achievement emotions were negatively associated with EFL performance. Moreover, factors inside the classroom, factors outside the classroom, and personal factors were found to be the antecedents of achievement emotions in EFL learning.

Therapeutic Targets of Bufalin on Renal Carcinoma and Mechanisms: Experimental Validation of Network Pharmacology Analysis.

The possible targets underlying the activity of bufalin on renal cell carcinoma (RCC) were investigated using network pharmacology and experimental approaches. PharmMapper and other databases were explored for predicting the bufalin targets and RCC-related targets. Finally, the enriched pathways and the targets were analyzed by the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) pathway enrichment analyses. Furthermore, in vitro cell experiments were used to verify bufalin activation of AKT and MAPK signaling pathways in human mesangial cells. The therapeutic targets related to bufalin were identified via 35 intersecting targets. GO analysis identified 29 molecular functions, 16 cellular components, and 91 biological processes. KEGG pathway annotation identified 15 signal transduction pathways and 4 tumor-related pathways.

Lipopeptide liposomes-loaded hydrogel for multistage transdermal chemotherapy of melanoma.

Transdermal administration of chemotherapeutics into tumor tissues may be an effective treatment to reduce toxic side effects and improve patient compliance for melanoma. Herein, we report a multistage transdermal drug delivery system for chemotherapy of melanoma. In this system, dendritic lipopeptide (DLP) modified multistage targeted liposomes (Mtlip) were incorporated into the hydrogel matrix to achieve localized and sustained drug release; Ultra-deformability of Mtlip can pass through dense stratum corneum to the epidermis where melanoma is located; Virus-mimicking Mtlip enhances the payload in tumor tissues by high permeability; The positive charged Mtlip can improve cell uptake efficiency and selectively accumulate into mitochondria to increases toxic. The efficacy of this type of multistage targeted liposomes loaded hydrogel in treating melanoma was systematically evaluated both in vitro and in vivo.

Simultaneous Quantification of 17 Cannabinoids by LC-MS-MS in Human Plasma.

In recent years, the surge in use of tetrahydrocannabinol (THC) and cannabidiol (CBD) has increased the need for sensitive and specific analytical assays to measure the said compounds in patients, to establish dose-effect relationships and to gain knowledge of their pharmacokinetics and metabolism. We developed and validated an online extraction high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS-MS) method for simultaneous quantification of 17 cannabinoids and metabolites including THC and its metabolites, CBD and its metabolites and other minor cannabinoids in human plasma. CBD-glucuronide (CBD-gluc) standard was produced in-house by isolation of CBD-gluc from urine of patients using pure CBD oil. For calibration standards and quality control samples, human plasma was spiked with cannabinoids at varying concentrations within the working range of the respective compound and 200 µL of the plasma was extracted using a simple one-step protein precipitation procedure. The extracts were analyzed using online trapping LC/LC-atmospheric pressure chemical ionization-MS-MS running in the positive multiple reaction monitoring mode. The lower limit of quantification ranged from 0.78 to 7.8 ng/mL, and the upper limits of quantification were between 100 and 2,000 ng/mL. Inter-day analytical accuracy and imprecision ranged from 90.4% to 111% and from 3.1% to 17.4%, respectively. The analysis of plasma samples collected during clinical studies showed that (3R-trans)-cannabidiol-7-oic acid (7-CBD-COOH) was the major human metabolite with 5960% (59.6-fold) of CBD followed by 7-hydroxy-CBD (177%), CBD-gluc (157%) and 6α-hydroxy-CBD (39.8%); 6ß-hydroxy-CBD was not detected in any of the samples. In the present study, we developed and validated a robust LC-MS-MS assay for the simultaneous quantification of cannabinoids and their metabolites, which has been used to measure >5,000 samples in clinical studies. Moreover, we were able to quantify CBD-gluc and showed that 7-CBD-COOH, 7-hydroxy-CBD and CBD-gluc are the major CBD metabolites in human plasma.

Microvesicles transfer mitochondria and increase mitochondrial function in brain endothelial cells.

We have demonstrated, for the first time that microvesicles, a sub-type of extracellular vesicles (EVs) derived from hCMEC/D3: a human brain endothelial cell (BEC) line transfer polarized mitochondria to recipient BECs in culture and to neurons in mice acute brain cortical and hippocampal slices. This mitochondrial transfer increased ATP levels by 100 to 200-fold (relative to untreated cells) in the recipient BECs exposed to oxygen-glucose deprivation, an in vitro model of cerebral ischemia. We have also demonstrated that transfer of microvesicles, the larger EV fraction, but not exosomes resulted in increased mitochondrial function in hypoxic endothelial cultures. Gene ontology and pathway enrichment analysis of EVs revealed a very high association to glycolysis-related processes. In comparison to heterotypic macrophage-derived EVs, BEC-derived EVs demonstrated a greater selectivity to transfer mitochondria and increase endothelial cell survival under ischemic conditions.

Lucifer Yellow - A Robust Paracellular Permeability Marker in a Cell Model of the Human Blood-brain Barrier.

The blood-brain barrier BBB consists of endothelial cells that form a barrier between the systemic circulation and the brain to prevent the exchange of non-essential ions and toxic substances. Tight junctions (TJ) effectively seal the paracellular space in the monolayers resulting in an intact barrier. This study describes a LY-based fluorescence assay that can be used to determine its apparent permeability coefficient (Papp) and in turn can be used to determine the kinetics of the formation of confluent monolayers and the resulting tight junction barrier integrity in hCMEC/D3 monolayers. We further demonstrate an additional utility of this assay to determine TJ functional integrity in transfected cells. Our data from the LY Papp assay shows that the hCMEC/D3 cells seeded in a transwell setup effectively limit LY paracellular transport 7 days-post culture. As an additional utility of the presented assay, we also demonstrate that the DNA nanoparticle transfection does not alter LY paracellular transport in hCMEC/D3 monolayers.