New advances in innate immune endosomal trafficking.

The exocytic and endocytic intracellular trafficking pathways in innate immune cells are known for mediating the secretion of key inflammatory mediators or the internalization of growth factors, nutrients, antigens, cell debris, pathogens and even therapeutics, respectively. Inside cells, these pathways are intertwined as an elaborate network that supports the regulation of immune functions. Endosomal membranes host dynamic platforms for molecular complexes that control signaling and inflammatory responses. High content screens, coupled with elegant microscopy across the scale of resolving molecular complexes to tracking live cellular organelles, have been employed to generate the studies highlighted here. With a focus on deactivation of STING, scaffolding by SLC15A4/TASL complexes and macropinosome shrinkage via the chloride channel protein TMEM206, new studies are identifying molecules, molecular interactions and mechanisms for immune regulation throughout endosomal pathways.

Unmet needs for rehabilitation service of middle-aged and older adult residents in Chengdu, Sichuan, China: A cross-sectional study.

To investigate the unmet needs for rehabilitation services among middle-aged and older adults in Chengdu, Sichuan, China, and identify the associated factors. This cross-sectional study was conducted on middle-aged and older adults in Chengdu, Sichuan, China, between 2015 and 2016. The questionnaire included demographic data and questions about rehabilitation needs. Multivariable logistic regression analysis was used to identify the associated factors of unmet needs for rehabilitation services. Among 663 participants, 91.70% needed medical rehabilitation (608/663), 26.55% of who need auxiliary equipment (176/663), 77.07% of who need daily care and social participation (511/663), and 79.34% of who need recreational therapy activities (526/663), while < 30% required auxiliary equipment. Multivariate logistic regression analysis showed that residents who were married, had annual income < CNY 80,000, had no medical insurance, had three or more health problems, were aged ≥ 60, and the disability status were independently associated with unmet needs for rehabilitation services (all P < 0.05). Marital status, annual income, medical insurance, health problems, and disability might be factors independently associated with the unmet needs for rehabilitation services. Attention should be paid to the financial burden of the population on rehabilitation services, and in addition to the disabled, the slow patients should also be given priority.

PTBP1 promotes hepatocellular carcinoma progression by regulating the skipping of exon 9 in NUMB pre-mRNA.

Aberrant alternative splicing is one of the important causes of cancer. Polypyrimidine tract binding protein 1 (PTBP1) has been found to be involved in splicing regulation in a variety of tumors. Here, we observed significant up-regulation of PTBP1 in primary hepatocellular carcinoma (HCC) tissues. High levels of PTBP1 expression were associated with poor prognosis and increased metastatic potential in HCC. In vitro studies demonstrated that elevated PTBP1 promoted both migration and invasion by HCC cells. In contrast, knockdown of PTBP1 significantly inhibited the migration and invasion of HCC cells in vitro. Further, up-regulation of PTBP1 markedly accumulated the expression of oncogenic isoform of NUMB, NUMB-PRRL. We observed two isoforms of NUMB, NUMB-PRRL and NUMB-PRRS exhibit opposite function in HCC cells, which partially explain PTBP1 plays the tumor promoting roles in a NUMB splicing-dependent manner. In summary, our study indicates that PTBP1 may serve as an oncogene in HCC patients by regulating the alternative splicing of NUMB exon 9 and could potentially serve as a prognostic indicator.

Analysis of the effectiveness of the application of pelvic floor rehabilitation exercise and the factors influencing its self-efficacy in postoperative patients with cervical cancer.

Objective: To analyze the application effect of pelvic floor rehabilitation exercise in postoperative patients with cervical cancer and the factors influencing their self-efficacy. Methods: 120 postoperative patients with cervical cancer from January 2019 to January 2022 from the Department of Rehabilitation, Aeronautical Industry Flying Hospital, Bayi Orthopaedic Hospital and Southwest Medical University Affiliated Hospital of Traditional Chinese Medicine, and the Department of Obstetrics and Gynecology, Chengdu Seventh People's Hospital, and the Department of Oncology, Sichuan Provincial People's Hospital were selected for the study. They were divided into routine group (n=44, applied routine care) and exercise group (n=76, applied routine care + pelvic floor rehabilitation exercise) according to the different perioperative care programs. The perioperative indicators, bladder function recovery rate and urinary retention incidence, urodynamic indicators, and pelvic floor distress inventory-short form 20 (PFDI-20) scores were compared between the 2 groups. The general data, PFDI-20 scores and broome pelvic muscle self-efficacy scale (BPMSES) scores of patients in the exercise group were investigated and analyzed individually to investigate the factors influencing the self-efficacy of patients with pelvic floor rehabilitation exercise after cervical cancer surgery. Results: The time of first anal exhaust, urine tube retention and hospitalization after surgery were shorter in the exercise group than in the routine group (P<0.05). The bladder function grade I rate after surgery was more in the exercise group than in the routine group, and the urinary retention incidence was lower than that in the routine group (P<0.05). At 2 weeks after exercise, bladder compliance and bladder detrusor systolic pressure were higher in both groups than before exercise, and they were higher in the exercise group than in the routine group (P<0.05). There was no significant difference in urethral closure pressure within and between the two groups (P>0.05). At 3 months after surgery, the PFDI-20 scores were higher in both groups than before surgery, and the exercise group was lower than the routine group (P<0.05).The BPMSES score for the exercise group was (103.33 ± 9.16). Marital status, residence and PFDI-20 scores were influential factors in the self-efficacy level of patients undergoing pelvic floor rehabilitation exercise after cervical cancer surgery (P<0.05). Conclusion: Implementing pelvic floor rehabilitation exercise for postoperative patients with cervical cancer can speed up the recovery of pelvic organ function and reduce the occurrence of postoperative urinary retention. Marital status, residence and PFDI-20 scores were influential factors in the self-efficacy level of patients undergoing pelvic floor rehabilitation exercise after cervical cancer surger, medical staff need to incorporate these clinical features to provide targeted nursing interventions to enhance patient compliance with training and improve postoperative survival quality.

New Drug Targets and Preclinical Modelling Recommendations for Treating Acute Myocardial Infarction.

Acute myocardial infarction (AMI) is the leading cause of morbidity and mortality worldwide and the primary underlying risk factor for heart failure. Despite decades of research and clinical trials, there are no drugs currently available to prevent organ damage from acute ischaemic injuries of the heart. In order to address the increasing global burden of heart failure, drug, gene, and cell-based regeneration technologies are advancing into clinical testing. In this review we highlight the burden of disease associated with AMI and the therapeutic landscape based on market analyses. New studies revealing the role of acid-sensitive cardiac ion channels and other proton-gated ion channels in cardiac ischaemia are providing renewed interest in pre- and post-conditioning agents with novel mechanisms of action that may also have implications for gene- and cell-based therapeutics. Furthermore, we present guidelines that couple new cell technologies and data resources with traditional animal modelling pipelines to help de-risk drug candidates aimed at treating AMI. We propose that improved preclinical pipelines and increased investment in drug target identification for AMI is critical to stem the increasing global health burden of heart failure.

FFP: joint Fast Fourier transform and fractal dimension in amino acid property-aware phylogenetic analysis.

BACKGROUND: Amino acid property-aware phylogenetic analysis (APPA) refers to the phylogenetic analysis method based on amino acid property encoding, which is used for understanding and inferring evolutionary relationships between species from the molecular perspective. Fast Fourier transform (FFT) and Higuchi's fractal dimension (HFD) have excellent performance in describing sequences' structural and complexity information for APPA. However, with the exponential growth of protein sequence data, it is very important to develop a reliable APPA method for protein sequence analysis. RESULTS: Consequently, we propose a new method named FFP, it joints FFT and HFD. Firstly, FFP is used to encode protein sequences on the basis of the important physicochemical properties of amino acids, the dissociation constant, which determines acidity and basicity of protein molecules. Secondly, FFT and HFD are used to generate the feature vectors of encoded sequences, whereafter, the distance matrix is calculated from the cosine function, which describes the degree of similarity between species. The smaller the distance between them, the more similar they are. Finally, the phylogenetic tree is constructed. When FFP is tested for phylogenetic analysis on four groups of protein sequences, the results are obviously better than other comparisons, with the highest accuracy up to more than 97%. CONCLUSION: FFP has higher accuracy in APPA and multi-sequence alignment. It also can measure the protein sequence similarity effectively. And it is hoped to play a role in APPA's related research.

Modelling urban flooding integrated with flow and sediment transport in drainage networks.

Drainage networks play an essential role in mitigating urban flooding, which, nevertheless, are prone to suffer sediment deposits. To date, however, the effects of sediments in drainage networks on urban flooding remain poorly understood. Here an integrated model is proposed for urban flooding. It is composed of a hydrological module for surface runoff integrated with a one-dimensional hydro-sediment-morphodynamic module for coupled open-channel or pressurized flow and sediment transport in drainage networks. The governing equations are solved synchronously using a well-balanced finite volume method. The model is tested against two laboratory cases involving mixed flow and sediment transport in pipes, and the results agree well with observed data. A new residential area with virtually pervious surface and an established urban area with essentially impervious surfaces are studied using the present model to unravel how sediments in drainage networks affect urban flooding under different extreme rainfall and sediment scenarios. The results reveal that sediments alter the discharge hydrographs in the drainage networks to distinct extents under different storm return periods. As far as the present computational cases are concerned, when a third of the pipe diameter is occupied by sediment deposits, the peak pipeline flow discharge decreases by up to 25 %. Accordingly, the surface inundation depth increases by up to 18 %, and the inundation area expands by up to 12 %, characterizing a considerably higher flooding risk. The present findings provide insight into the influences of sediment transport in drainage networks on urban flooding.

Significant role of long non-coding RNA MALAT1 in deep vein thrombosis via the regulation of vascular endothelial cell physiology through the microRNA-383-5p/BCL2L11 axis.

Deep vein thrombosis (DVT) is a vascular disease. The long non-coding RNA (lncRNA), metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), is positively expressed in DVT tissues, and regulates the biological behavior of endothelial progenitor cells. Here, we explored whether MALAT1 affected the physiology of human vascular endothelial cells (HUVECs) and analyzed its underlying mechanism. To overexpress/silence the expression of MALAT1 in HUVECs, MALAT1-plasmid/MALAT1-small interfering RNA (siRNA) was used. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and flow cytometry analyses were performed to observe the cell viability and apoptosis. Reverse transcription-quantitative polymerase chain reaction and western blotting were used to determine the apoptosis-related protein and gene expression levels. We used Starbase software to predict the associations among MALAT1, microRNA (miR)-383-5p, and BCL2-like 11 (BCL2L11). Luciferase reporter assay was used to validate their relationship. Compared to the control vector group, MALAT1-plasmid suppressed the viability and induced apoptosis of HUVECs, while improving Bcl-2-associated X protein (Bax) expression and decreasing Bcl-2 expression. There was an interaction between MALAT1 and miR-383-5p. Compared to the control siRNA group, MALAT1-siRNA increased the cell viability, reduced cell apoptosis, upregulated Bcl-2 expression, and suppressed Bax expression. These changes were reversed by the miR-383-5p inhibitor. Additionally, we verified that BCL2L11 is a target of miR-383-5p. miR-383-5p improved the cell proliferation, while decreasing cell apoptosis in HUVECs by targeting BCL2L11. Therefore, the lncRNA-MALAT1/miR-383-5p/BCL2L11 axis may be effective for DVT treatment.

Coupled modelling of flow and non-capacity sediment transport in sewer flushing channel.

Flushing is cost-effective for mitigating sediments and constraining environmental problems in sewer systems. Previous mathematical models are almost exclusively built upon simplified governing equations evoking the assumptions of slow bed evolution and sediment transport capacity, of which the applicability remains open to question. Here a 1D coupled non-capacity model is presented for non-uniform sediment transport in sewer flushing channels, as adapted from recently established shallow water hydro-sediment-morphodynamic models for fluvial processes. The present model is tested for an experimental flushing case in Paris's Des Coteaux catchment system. The computational results agree with observed data more closely than those of a previous decoupled capacity model. While the differences between decoupled and capacity models and the present coupled non-capacity model are minor for flushing processes of short-durations, they are more pronounced for sustained long-duration flushing processes. Physically, the adaptation of suspended sediments to capacity regime cannot be fulfilled quickly, though bedload sediments can adapt to capacity regime instantly. Also, the bed deformation rate is comparable to its counterpart of the flow depth. Therefore, coupled non-capacity modelling is suggested for general applications to sewer flushing channels, of which the computing cost is essentially equivalent to simplified models built upon decoupling and capacity assumptions.

Study on the Mechanism of Platelet-Released Clusterins Inducing Restenosis after Carotid Endarterectomy by Activating TLR3/NF-κb p65 Signaling Pathway.

This study aimed to explore the role of clusterin released by platelet aggregation in restenosis after carotid endarterectomy. 35 patients who underwent carotid endarterectomy due to carotid artery stenosis were enrolled in this study. They were admitted to the Third Affiliated Hospital of Qiqihar Medical University from January 2018 to January 2019. All the patients were divided into two groups: the restenosis group and the nonrestenosis group, according to the follow-up results within 12 months. Peripheral blood was collected on the first day, 6 months, and 12 months after operation. The expression of CLU in serum of plasma and platelet culture medium was detected by an ELISA experiment. The vascular endothelial cells were cultured in vitro with 100 ng/mL of human recombinant CLU added to the medium. Cell proliferation, migration, and invasion were detected by CCK8, scratch, and Transwell invasion tests. The expression level of TLR3 and NF-κb p65 proteins in cells was detected by western blot. TLR3 knockout plasmids in vascular endothelial cell lines were transfected. Cell proliferation and migration were detected by CCK8 and the scratch assay. The CLU content in peripheral blood plasma and supernatant of platelet culture medium was significantly higher in the restenosis group than that of the control group (p=0.003) 6 months after operation (p=0.047) and 12 months after operation (p=0.011). When CLU was added to vascular endothelial cell culture medium, the proliferation and migration were significantly enhanced. The TLR3/NF-κb p65 protein expression level in cells also significantly increased. After the transfection of TLR3 knockout plasmids into vascular endothelial cell lines, CLU cannot promote the proliferation and migration of vascular endothelial cells. Platelet-released clusterin can induce vascular endothelial cell proliferation and migration by activating the TLR3/NF-kb p65 signaling pathway, leading to carotid artery restenosis after carotid endarterectomy.

Combined Effect of Flaxseed Oil and Vitamin E Supplementation During Bull Semen Cryopreservation on Sperm Characteristics.

The present study was performed to investigate the effects of supplementing flaxseed oil (FO) or vitamin E (VE) or their combination to an extender for Simmental bull semen cryopreservation. In experiment 1, different concentrations of FO (0, 10, 100, and 1000 ng/mL) and VE (0.05, 0.1, and 0.2 mg/mL) were added to the extenders. In experiment 2, FO, VE, and FO + VE were added and a control group was included. Sperm viability, motility, motion parameters, acrosome integrity and membrane integrity, endogenous antioxidant indices, reactive oxygen species, and malondialdehyde levels were evaluated after semen thawing. A higher percentage of viability, motion parameters, endogenous antioxidant indices, and membrane integrity was observed after supplementation with 10 ng/mL FO or 0.1 mg/mL VE compared with the control group (p < 0.05). Also, combined supplementation of 10 ng/mL FO +0.1 mg/mL VE further improved the quality of frozen-thawed sperm by regulating viability, motion parameters, membrane integrity, and endogenous antioxidant indices compared with the FO or VE alone (p < 0.05). These results indicated that FO (10 ng/mL) + VE (0.1 mg/mL) could further improve the protective effects on bull sperm post-thaw.

Circ-HOMER1 enhances the inhibition of miR-1322 on CXCL6 to regulate the growth and aggressiveness of hepatocellular carcinoma cells.

Hepatocellular carcinoma (HCC) is a common liver malignancy worldwide accompanying with the high rate of recurrence. Accumulating reports have documented the significance of circular RNAs (circRNAs) in carcinogenesis and development of HCC. This study aimed to establish the mechanism underlying circ-HOMER1 involvement in HCC. To this end, we identified a binding site for miR-1322 via bioinformatics, quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR), and dual-luciferase reporter assays providing evidence of a direct link between circ-HOMER1 and miR-1322. Similarly, the target gene of miR-1322 was investigated. Moreover, we determined the specific function of circ-HOMER1 in HCC with the aid of qRT-PCR based on patient clinical records, Cell Counting Kit-8, acridine orange/ethidium bromide double fluorescence staining, flow cytometry, and wound-healing and transwell assays. Notably, circ-HOMER1 was upregulated in both HCC cells and tissues. This aberrant expression pattern was closely correlated with larger tumor size, higher tumor-node-metastasis stage, and poorer prognosis for the patients with HCC. Moreover, silenced circ-HOMER1 inhibited cell proliferation, migration, and invasion concomitant with the promotion of apoptosis in HCC cells, and vice versa. Mechanistically, circ-HOMER1 enhanced the inhibition of miR-1322 on CXCL6 in HCC. Furthermore, we found that circ-HOMER1 promoted HCC cell growth and aggressiveness by miR-1322/CXCL6 axis. This study may provide a potential prognostic indicator and therapeutic target for patients with HCC.

Modification of distinct ion channels differentially modulates Ca2+ dynamics in primary cultured rat ventricular cardiomyocytes.

Primary cultured cardiomyocytes show spontaneous Ca2+ oscillations (SCOs) which not only govern contractile events, but undergo derangements that promote arrhythmogenesis through Ca2+ -dependent mechanism. We systematically examined influence on SCOs of an array of ion channel modifiers by recording intracellular Ca2+ dynamics in rat ventricular cardiomyocytes using Ca2+ specific fluorescence dye, Fluo-8/AM. Voltage-gated sodium channels (VGSCs) activation elongates SCO duration and reduces SCO frequency while inhibition of VGSCs decreases SCO frequency without affecting amplitude and duration. Inhibition of voltage-gated potassium channel increases SCO duration. Direct activation of L-type Ca2+ channels (LTCCs) induces SCO bursts while suppressing LTCCs decreases SCO amplitude and slightly increases SCO frequency. Activation of ryanodine receptors (RyRs) increases SCO duration and decreases both SCO amplitude and frequency while inhibiting RyRs decreases SCO frequency without affecting amplitude and duration. The potencies of these ion channel modifiers on SCO responses are generally consistent with their affinities in respective targets demonstrating that modification of distinct targets produces different SCO profiles. We further demonstrate that clinically-used drugs that produce Long-QT syndrome including cisapride, dofetilide, sotalol, and quinidine all induce SCO bursts while verapamil has no effect. Therefore, occurrence of SCO bursts may have a translational value to predict cardiotoxicants causing Long-QT syndrome.

Activation of sodium channels by α-scorpion toxin, BmK NT1, produced neurotoxicity in cerebellar granule cells: an association with intracellular Ca2+ overloading.

Voltage-gated sodium channels (VGSCs) are responsible for the action potential generation in excitable cells including neurons and involved in many physiological and pathological processes. Scorpion toxins are invaluable tools to explore the structure and function of ion channels. BmK NT1, a scorpion toxin from Buthus martensii Karsch, stimulates sodium influx in cerebellar granule cells (CGCs). In this study, we characterized the mode of action of BmK NT1 on the VGSCs and explored the cellular response in CGC cultures. BmK NT1 delayed the fast inactivation of VGSCs, increased the Na+ currents, and shifted the steady-state activation and inactivation to more hyperpolarized membrane potential, which was similar to the mode of action of α-scorpion toxins. BmK NT1 stimulated neuron death (EC50 = 0.68 µM) and produced massive intracellular Ca2+ overloading (EC50 = 0.98 µM). TTX abrogated these responses, suggesting that both responses were subsequent to the activation of VGSCs. The Ca2+ response of BmK NT1 was primary through extracellular Ca2+ influx since reducing the extracellular Ca2+ concentration suppressed the Ca2+ response. Further pharmacological evaluation demonstrated that BmK NT1-induced Ca2+ influx and neurotoxicity were partially blocked either by MK-801, an NMDA receptor blocker, or by KB-R7943, an inhibitor of Na+/Ca2+ exchangers. Nifedipine, an L-type Ca2+ channel inhibitor, slightly suppressed both Ca2+ response and neurotoxicity. A combination of these three inhibitors abrogated both responses. Considered together, these data ambiguously demonstrated that activation of VGSCs by an α-scorpion toxin was sufficient to produce neurotoxicity which was associated with intracellular Ca2+ overloading through both NMDA receptor- and Na+/Ca2+ exchanger-mediated Ca2+ influx.

Chemical synthesis and biological evaluation of ω-hydroxy polyunsaturated fatty acids.

ω-Hydroxy polyunsaturated fatty acids (PUFAs), natural metabolites from arachidonic acid (ARA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were prepared via convergent synthesis approach using two key steps: Cu-mediated CC bond formation to construct methylene skipped poly-ynes and a partial alkyne hydrogenation where the presence of excess 2-methyl-2-butene as an additive that is proven to be critical for the success of partial reduction of the poly-ynes to the corresponding cis-alkenes without over-hydrogenation. The potential biological function of ω-hydroxy PUFAs in pain was evaluated in naive rats. Following intraplantar injection, 20-hydroxyeicosatetraenoic acid (20-HETE, ω-hydroxy ARA) generated an acute decrease in paw withdrawal thresholds in a mechanical nociceptive assay indicating pain, but no change was observed from rats which received either 20-hydroxyeicosapentaenoic acid (20-HEPE, ω-hydroxy EPA) or 22-hydroxydocosahexaenoic acid (22-HDoHE, ω-hydroxy DHA). We also found that both 20-HEPE and 22-HDoHE are more potent than 20-HETE to activate murine transient receptor potential vanilloid receptor1 (mTRPV1).

Impacts of Three Gorges Reservoir on the sedimentation regimes in the downstream-linked two largest Chinese freshwater lakes.

We studied the impacts of Three Gorges Reservoir (TGR) on the sedimentation regimes in the downstream-linked two largest Chinese freshwater lakes, Lake Dongting and Lake Poyang. Our results indicate that up to 1.73 × 109 t sediment was retained in TGR from June 2003 to December 2014. This resulted in a 145.9 × 106 t yr-1 decline in the suspended sediment load at Zhicheng and a 16.8 × 106 t yr-1 lower sediment flow from Yangtze River to Lake Dongting, which partially explains the 13.4 × 106 t yr-1 lower sedimentation in Lake Dongting during the post-TGR period. Furthermore, TGR resulted in a 0.5 ± 0.3 m reduction of the multi-year mean water level at the Lake Poyang outlet Hukou, accelerating the suspended sediment export discharge from the lake. The reduced sedimentation in Lake Poyang during the post-TGR period was estimated to 6.3 × 106 t yr-1. We estimate that a monthly mean concentration of sediment flow from TGR below 0.60 kg m-3 will lead to erosion in Lake Dongting and Lake Poyang. Better regulation of TGR may extend the life expectancy of the two vanishing large lakes.

Development of a Rapid Throughput Assay for Identification of hNav1.7 Antagonist Using Unique Efficacious Sodium Channel Agonist, Antillatoxin.

Voltage-gated sodium channels (VGSCs) are responsible for the generation of the action potential. Among nine classified VGSC subtypes (Nav1.1-Nav1.9), Nav1.7 is primarily expressed in the sensory neurons, contributing to the nociception transmission. Therefore Nav1.7 becomes a promising target for analgesic drug development. In this study, we compared the influence of an array of VGSC agonists including veratridine, BmK NT1, brevetoxin-2, deltamethrin and antillatoxin (ATX) on membrane depolarization which was detected by Fluorescence Imaging Plate Reader (FLIPR) membrane potential (FMP) blue dye. In HEK-293 cells heterologously expressing hNav1.7 α-subunit, ATX produced a robust membrane depolarization with an EC50 value of 7.8 ± 2.9 nM whereas veratridine, BmK NT1, and deltamethrin produced marginal response. Brevetoxin-2 was without effect on membrane potential change. The ATX response was completely inhibited by tetrodotoxin suggesting that the ATX response was solely derived from hNav1.7 activation, which was consistent with the results where ATX produced a negligible response in null HEK-293 cells. Six VGSC antagonists including lidocaine, lamotrigine, phenytoin, carbamazepine, riluzole, and 2-amino-6-trifluoromethylthiobenzothiazole all concentration-dependently inhibited ATX response with IC50 values comparable to that reported from patch-clamp experiments. Considered together, we demonstrate that ATX is a unique efficacious hNav1.7 activator which offers a useful probe to develop a rapid throughput screening assay to identify hNav1.7 antagonists.

Cardiotoxicity screening: a review of rapid-throughput in vitro approaches.

Cardiac toxicity represents one of the leading causes of drug failure along different stages of drug development. Multiple very successful pharmaceuticals had to be pulled from the market or labeled with strict usage warnings due to adverse cardiac effects. In order to protect clinical trial participants and patients, the International Conference on Harmonization published guidelines to recommend that all new drugs to be tested preclinically for hERG (Kv11.1) channel sensitivity before submitting for regulatory reviews. However, extensive studies have demonstrated that measurement of hERG activity has limitations due to the multiple molecular targets of drug compound through which it may mitigate or abolish a potential arrhythmia, and therefore, a model measuring multiple ion channel effects is likely to be more predictive. Several phenotypic rapid-throughput methods have been developed to predict the potential cardiac toxic compounds in the early stages of drug development using embryonic stem cells- or human induced pluripotent stem cell-derived cardiomyocytes. These rapid-throughput methods include microelectrode array-based field potential assay, impedance-based or Ca(2+) dynamics-based cardiomyocytes contractility assays. This review aims to discuss advantages and limitations of these phenotypic assays for cardiac toxicity assessment.

Involvement of JNK and caspase activation in hoiamide A-induced neurotoxicity in neocortical neurons.

The frequent occurrence of Moorea producens (formerly Lyngbya majuscula) blooms has been associated with adverse effects on human health. Hoiamide A is a structurally unique cyclic depsipeptide isolated from an assemblage of the marine cyanobacteria M. producens and Phormidium gracile. We examined the influence of hoiamide A on neurite outgrowth in neocortical neurons and found that it suppressed neurite outgrowth with an IC50 value of 4.89 nM. Further study demonstrated that hoiamide A stimulated lactic acid dehydrogenase (LDH) efflux, nuclear condensation and caspase-3 activity with EC50 values of 3.66, 2.55 and 4.33 nM, respectively. These data indicated that hoiamide A triggered a unique neuronal death profile that involves both necrotic and apoptotic mechanisms. The similar potencies and similar time-response relationships between LDH efflux and caspase-3 activation/nuclear condensation suggested that both necrosis and apoptosis may derive from interaction with a common molecular target. The broad-spectrum caspase inhibitor, Z-VAD-FMK completely inhibited hoiamide A-induced neurotoxicity. Additionally, hoiamide A stimulated JNK phosphorylation, and a JNK inhibitor attenuated hoiamide A-induced neurotoxicity. Collectively, these data demonstrate that hoiamide A-induced neuronal death requires both JNK and caspase signaling pathways. The potent neurotoxicity and unique neuronal cell death profile of hoiamide A represents a novel neurotoxic chemotype from marine cyanobacteria.

Effects of novel single nucleotide polymorphisms of the FSH beta-subunit gene on semen quality and fertility in bulls.

The follicle-stimulating hormone (FSH) acts on the Sertoli cells in the seminiferous tubules of the testis and regulates spermatogenesis up to the secondary spermatocyte stage. This study aimed to investigate molecular genetic characteristics of the bovine FSH beta-subunit gene (FSHB) and elucidate the effects of single nucleotide polymorphisms (SNPs) of FSHB on the quality of fresh and frozen semen and on fertility in bulls. We used polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) and sequencing of the FSHB gene in 56 bulls belonging to three breeds. We identified 13 substitutions and 1 insertion in the upstream regulation region and in the coding region of exon 3, which were all linked together. Bioinformatics analysis suggested that mutations of the 5'-upstream regulation region altered the binding sites for transcription factors, and radioimmunoassay demonstrated that mutations may result in alterations in the serum FSH concentrations. The least-squares analysis revealed that bulls with this genotype exhibited a significantly lower sperm concentration in fresh semen and a lower percentage of acrosome integrity in both fresh and frozen semen (P<0.05). These bulls also exhibited a significantly higher percentage of sperm deformity in fresh semen (P<0.05), which was more pronounced in frozen semen (P<0.01), and a significantly lower sperm motility in frozen semen (P<0.05). For fertility evaluation, the nonreturn rates obtained from 14,416 inseminations with the analyzed batches revealed that bulls with this genotype showed significantly lower nonreturn rates (P<0.05). In other words, bulls with this genotype exhibited lower semen quality, poor freeze resistance, and lower fertility. These results suggest that the SNPs in bovine FSHB are associated with semen quality and fertility in bulls.