Inhibition of histone deacetylase promotes a neuroprotective mechanism in an experimental model of Parkinson's disease.

Introduction: Therapies targeting histone deacetylase (HDAC) have gained wider attention in the treatment of various clinical conditions. However, the use of HDAC inhibitors in pre-clinical trials in the case of Parkinson's disease (PD) is very limited. In the present study, the HDAC inhibitor, entinostat, was tested in animals induced with Parkinson's disease experimentally. Material and methods: Wistar male rats (150 ±10 g) were administered with rotenone (2 mg/kg/day, s.c.) for 21 days to induce PD, while entinostat (20 mg/kg) was given intraperitoneally. Then, the neurological functions, PD markers, and HDACs were analysed in the control and experimental animals. Results: The results demonstrated that rats that received entinostat displayed progressive motor, behavioural, and neurological function with attenuated α-synuclein and improved tyrosine-hydroxylase compared to control cells. Moreover, the induction of PD in rats demonstrated reduced levels of H2S, dopamine, 3, and 4-dihydroxyphenylacetic acid (DOPAC), and increased monoamine oxidase activity in PD rats. However, the rats that received entinostat demonstrated progressive levels of dopa and DOPAC, with attenuated levels of HDAC-2, -4, and -6 mRNA in the PD rats compared to controls. On the other hand, elevated (p < 0.01) levels of PD marker genes such as GDF3 and NMDA2b were reduced, with a significant increase in neuroprotective genes such as VDAC3 and CBX5 in entinostat-supplemented rats. Conclusions: The study results suggest that inhibition of HDAC systematically improves the neurological functions, and hence treatments, emphasizing that HDACI, as the speculated mechanism, will be a promising mode of treatment in PD.

Systematic genome-wide Mendelian randomization reveals the causal links between miRNAs and Parkinson's disease.

Background: MicroRNAs (miRNAs) have pivotal roles in gene regulation. Circulating miRNAs have been developed as novel candidate non-invasive biomarkers for diagnosis, prognosis, and treatment response for diseases. However, miRNAs that have causal effects on Parkinson's Disease (PD) remain largely unknown. To investigate the causal relationships between miRNAs and PD, here we conduct a Mendelian randomization (MR) study. Methods: This study utilized the summary-level data of respective genome-wide association studies (GWAS) for 2083 miRNAs and seven PD-related outcomes to comprehensively reveal the causal associations between the circulating miRNAs and PD. Two-sample MR design was deployed and the causal effects were estimated with inverse variance weighted, MR-Egger, and weighted median. Comprehensively sensitive analyses were followed, including Cochran's Q test, MR-Egger intercept test, MR-PRESSO, and leave-one-out analysis, to validate the robustness of our results. Finally, we investigated the potential role of the MR significant miRNAs by predicting their target genes and functional enrichment analysis. Results: Inverse variance weighted estimates suggested that two miRNAs, miR-205-5p (ß = -0.46, 95%CI: -0.690 to -0.229, p = 9.3 × 10-5) and miR-6800-5p (ß = -0.389, 95%CI: -0.575 to -0.202, p = 4.32 × 10-5), significantly decreased the rate of cognitive decline among PD patients. In addition, eight miRNAs were nominally associated with more than three PD-related outcomes each. No significant heterogeneity of instrumental variables or horizontal pleiotropy was found. Gene Ontology (GO) analysis showed that the targets of these causal miRNAs were significantly enriched in cell cycle, apoptotic, and aging pathways. Conclusion: This MR study identified two miRNAs whose genetically regulated expression might have a causal role in the development of PD dementia. Our findings provided potential miRNA biomarkers to make better and early diagnoses and risk assessments of PD.

The impact of gut microbial signals on hematopoietic stem cells and the bone marrow microenvironment.

Hematopoietic stem cells (HSCs) undergo self-renewal and differentiation in the bone marrow, which is tightly regulated by cues from the microenvironment. The gut microbiota, a dynamic community residing on the mucosal surface of vertebrates, plays a crucial role in maintaining host health. Recent evidence suggests that the gut microbiota influences HSCs differentiation by modulating the bone marrow microenvironment through microbial products. This paper comprehensively analyzes the impact of the gut microbiota on hematopoiesis and its effect on HSCs fate and differentiation by modifying the bone marrow microenvironment, including mechanical properties, inflammatory signals, bone marrow stromal cells, and metabolites. Furthermore, we discuss the involvement of the gut microbiota in the development of hematologic malignancies, such as leukemia, multiple myeloma, and lymphoma.

Association between gut microbiota and sensorineural hearing loss: a Mendelian randomization study.

Background: Several recent studies speculated that the gut microbiota is associated with sensorineural hearing loss (SNHL) and proposed the concept of the gut-inner ear axis. However, the causal effect of gut microbiota on SNHL is still unknown. In this study, we performed a two-sample Mendelian randomization (MR) analysis to estimate the causal effect of gut microbiota on SNHL. Methods: Gut microbiota data were obtained from the largest available genome-wide association study (n = 18,340) conducted by the MiBioGen consortium. The summary statistics of SNHL were obtained from the FinnGen consortium R8 release data (28,310 cases and 302,750 controls). The causal effects were estimated with inverse-variance weighted, MR-Egger, and weighted median. Reverse Mendelian randomization analysis was performed on the bacteria that were found to be associated with SNHL in forward Mendelian randomization analysis. We then performed sensitivity analyses, including Cochran's Q-test, MR-Egger intercept test, MR-PRESSO, cML-MA-BIC, and leave-one-out analysis, to detect heterogeneity and pleiotropy. Results: The inverse-variance weighted results suggested that Lachnospiraceae (UCG001) had a significant protective effect against SNHL (odds ratio = 0.85, 95% confidence interval: 0.78-0.93, P = 6.99 × 10-4). In addition, Intestinimonas (odds ratio = 0.89, 95% confidence interval: 0.82-0.97, P = 8.53 × 10-3) presented a suggestively protective effect on SNHL. Rikenellaceae (RC9gutgroup) (odds ratio = 1.08, 95% confidence interval: 1.02-1.15, P = 0.01) and Eubacterium (hallii group) (odds ratio = 1.12, 95% confidence interval: 1.00-1.24, P = 0.048) suggestively increase the risk of SNHL. The results of the reverse MR analysis showed that there is no significant causal effect of SNHL on the gut microbiota. No significant heterogeneity of instrumental variables or pleiotropy was detected. Conclusion: The evidence that the four genera mentioned above are associated with SNHL supports the hypothesis of a gut-inner ear axis. Our study provides microbial markers for the prevention and treatment of SNHL, and further studies are needed to explore the mechanisms of the gut microbiome-inner ear axis in health and diseases.

The spatiotemporal heterogeneity of the biophysical microenvironment during hematopoietic stem cell development: from embryo to adult.

Hematopoietic stem cells (HSCs) with the ability to self-renew and differentiate are responsible for maintaining the supply of all types of blood cells. The complex and delicate microenvironment surrounding HSCs is called the HSC niche and can provide physical, chemical, and biological stimuli to regulate the survival, maintenance, proliferation, and differentiation of HSCs. Currently, the exploration of the biophysical regulation of HSCs remains in its infancy. There is evidence that HSCs are susceptible to biophysical stimuli, suggesting that the construction of engineered niche biophysical microenvironments is a promising way to regulate the fate of HSCs in vitro and ultimately contribute to clinical applications. In this review, we introduced the spatiotemporal heterogeneous biophysical microenvironment during HSC development, homeostasis, and malignancy. Furthermore, we illustrated how these biophysical cues contribute to HSC behaviors, as well as the possible mechanotransduction mechanisms from the extracellular microenvironment into cells. Comprehending the important functions of these biophysical regulatory factors will provide novel approaches to resolve clinical problems.

Cascade amplification of tumor chemodynamic therapy and starvation with re-educated TAMs via Fe-MOF based functional nanosystem.

Tumor microenvironment is characterized by the high concentration of reactive oxygen species (ROS), which is an effective key used to open the Pandora's Box against cancer. Herein, a tumor-targeted nanosystem HFNP@GOX@PFC composed of ROS-cleaved Fe-based metal-organic framework, hyaluronic acid (HA), glucose oxidase (GOX) and perfluorohexane (PFC) has been developed for tumor cascade amplified starvation and chemodynamic therapy (CDT). In response to the high concentration of hydrogen peroxide (H2O2) intratumorally, HFNP@GOX@PFC endocytosed by tumor cells can specially be disassembled and release GOX, PFC and Fe2+, which can collectively starve tumor and self-produce additional H2O2 via competitively glucose catalyzing, supply oxygen to continuous support GOX-mediated starvation therapy, initiate CDT and cascade amplify oxidative stress via Fe2+-mediated Fenton reaction, leading to the serious tumor damage with activated p53 signal pathway. Moreover, HFNP@GOX@PFC also significantly initiates antitumor immune response via re-educating tumor-associated macrophages (TAMs) by activating NF-κB and MAPK signal pathways. In vitro and in vivo results collectively demonstrate that nanosystem not only continuously initiates starvation therapy, but also pronouncedly cascade-amplify CDT and polarize TAMs, consequently efficiently inhibiting tumor growth with good biosafety. The functional nanosystem combined the cascade amplification of starvation and CDT provides a new nanoplatform for tumor therapy.

[Application of multivariate models in whole process control of solid preparations].

The production of solid preparations is a multi-unit and multi-step system and is a whole process chain. Its quality is affected by many factors such as material properties and process parameters. As an important analysis tool, multivariate models play an important role in pharmaceutical monitoring. Besides, multivariate models can comprehensively understand the multi-factor relationship between material properties, process parameters, and quality attributes of products, thereby promoting the whole process optimization and controlling the drug production quality. This paper summarized the application of commonly used multivariate models in the process of solid preparations, which provides a certain reference for the process modeling of Chinese medicinal preparations.

Analysis of the effects of magnetic levitation to simulate microgravity environment on the Arp2/3 complex pathway in macrophage.

With dwindling natural resources on earth, current and future generations will need to explore space to new planets that will require travel under no or varying gravity conditions. Hence, long-term space missions and anticipated impacts on human biology such as changes in immune function are of growing research interest. Here, we reported new findings on mechanisms of immune response to microgravity with a focus on macrophage as a cellular model. We employed a superconducting magnet to generate a simulated microgravity environment and evaluated the effects of simulated microgravity on RAW 264.7 mouse macrophage cell line in three time frames: 8, 24, and 48 h. As study endpoints, we measured cell viability, phagocytosis, and used next-generation sequencing to explore its changing mechanism. Macrophage cell viability and phagocytosis both showed a marked decrease under microgravity. The differentially expressed genes (DEG) were identified in two ways: (1) gravity-dependent DEG, compared µg samples and 1 g samples at each time point; (2) time-dependent DEG, compared time-point samples within the same gravitational field. Through transcriptome analysis and confirmed by molecular biological verification, our findings firstly suggest that microgravity might affect macrophage phagocytosis by targeting Arp2/3 complex involved cytoskeleton synthesis and causing macrophage immune dysfunction. Our findings contribute to an emerging body of scholarship on biological effects of space travel.

Roles of α­synuclein in gastrointestinal microbiome dysbiosis­related Parkinson's disease progression (Review).

Parkinson's disease (PD) is the second most common neurodegenerative disease amongst the middle­aged and elderly populations. Several studies have confirmed that the microbiota­gut­brain axis (MGBA) serves a key role in the pathogenesis of PD. Changes to the gastrointestinal microbiome (GM) cause misfolding and abnormal aggregation of α­synuclein (α­syn) in the intestine. Abnormal α­syn is not eliminated via physiological mechanisms and is transported into the central nervous system (CNS) via the vagus nerve. The abnormal levels of α­syn aggregate in the substantia nigra pars compacta, not only leading to the formation of eosinophilic Lewis Bodies in the cytoplasm and mitochondrial dysfunction in dopaminergic (DA) neurons, but also leading to the stimulation of an inflammatory response in the microglia. These pathological changes result in an increase in oxidative stress (OS), which triggers nerve cell apoptosis, a characteristic of PD. This increase in OS further oxidizes and intensifies abnormal aggregation of α­syn, eventually forming a positive feedback loop. The present review discusses the abnormal accumulation of α­syn in the intestine caused by the GM changes and the increased levels of α­syn transport to the CNS via the MGBA, resulting in the loss of DA neurons and an increase in the inflammatory response of microglial cells in the brain of patients with PD. In addition, relevant clinical therapeutic strategies for improving the GM and reducing α­syn accumulation to relieve the symptoms and progression of PD are described.

Study on the Mechanism of Ionic Liquids Improving the Extraction Efficiency of Essential Oil Based on Experimental Optimization and Density Functional Theory: The Fennel (Foeniculi fructus) Essential Oil Case.

In this work, microwave-assisted ionic liquids treatment, followed by hydro-distillation (MILT-HD), as an efficient extraction technology, was used to extract essential oil. The purpose for this was to use multivariate analysis (MVA) models to investigate the effects of potential critical process parameters on the extraction efficiency of essential oil, and explore the mechanism of ionic liquids (ILs). According to the design of experiment (DoE), under optimal process conditions, the extraction efficiency of essential oil was dramatically enhanced, and had low energy demands. Since little is known regarding those mechanisms, according to the non-covalent interaction analysis, the underlying mechanism for ILs improving extraction efficiency was explored based on the density functional theory (DFT). The results showed that ILs could form intense non-covalent bond interaction with cellulose. It helped destroy the network hydrogen bond structure of cellulose in plant cells and caused the essential oils in the cells to be more easily exposed to the extraction solution, thereby accelerating extraction efficiency. Based on this work, it is conducive to understand the MILT-HD process better and gain knowledge of the mechanism of ILs.

Pharmaceutical application of multivariate modelling techniques: a review on the manufacturing of tablets.

The tablet manufacturing process is a complex system, especially in continuous manufacturing (CM). It includes multiple unit operations, such as mixing, granulation, and tableting. In tablet manufacturing, critical quality attributes are influenced by multiple factorial relationships between material properties, process variables, and interactions. Moreover, the variation in raw material attributes and manufacturing processes is an inherent characteristic and seriously affects the quality of pharmaceutical products. To deepen our understanding of the tablet manufacturing process, multivariable modeling techniques can replace univariate analysis to investigate tablet manufacturing. In this review, the roles of the most prominent multivariate modeling techniques in the tablet manufacturing process are discussed. The review mainly focuses on applying multivariate modeling techniques to process understanding, optimization, process monitoring, and process control within multiple unit operations. To minimize the errors in the process of modeling, good modeling practice (GMoP) was introduced into the pharmaceutical process. Furthermore, current progress in the continuous manufacturing of tablets and the role of multivariate modeling techniques in continuous manufacturing are introduced. In this review, information is provided to both researchers and manufacturers to improve tablet quality.

[Potential molecular mechanism of Banxia Xiexin Decoction in treatment of colon cancer based on network pharmacology and molecular docking technology].

The aim of this paper was to explore the potential molecular mechanism of Banxia Xiexin Decoction in the treatment of colon cancer through pharmacology network and molecular docking methods. The chemical constituents and action targets of 7 herbs from Banxia Xiexin Decoction were collected by using TCMSP database,Chinese Pharmacopoeia and literatures consultation. GeneCards database was used to predict the potential targets of colon cancer. GO biological process analysis and KEGG pathway enrichment analysis of the disease and drug intersection targets were carried out through DAVID database. "Component-target-pathway" network and protein-protein interaction(PPI) network were construction by using Cytoscape and STRING database,and then the core components and targets of Banxia Xiexin Decoction in the treatment of colon cancer were selected according to the topological parameters. Finally, Autodock Vina was used to realize the molecular docking of core components and key targets. The prediction results showed that there were 190 active compounds and 324 corresponding targets for Banxia Xiexin Decoction,involving 74 potential targets for colon cancer. Cytoscape topology analysis revealed 11 key targets such as STAT3,TP53,AKT1,TNF,IL6 and SRC, as well as 10 core components such as quercetin,ß-sitosterol,baicalein,berberine,and 6-gingerol.In bioinformatics enrichment analysis, 679 GO terms and 106 KEGG pathways were obtained, mainly involving PI3 K-AKT signaling pathway,TNF signaling pathway and TP53 signaling pathway. The results of molecular docking showed that baicalein,berberine,licochalcone A and 6-gingerol had a high affinity with SRC,STAT3,TNF and IL6. The results suggested that Banxia Xiexin Decoction could play an anti-colon cancer effect by inhibiting cell proliferation, regulating cell cycle, inducing apoptosis and anti-inflammatory function. The study revealed the multi-components,multi-targets and multi-pathways molecular mechanism of Banxia Xiexin Decoction,which could provide scientific basis and research ideas for the clinical application of Banxia Xiexin Decoction and the treatment of colon cancer with compound Chinese medicines.

Evolutionary History, Genomic Adaptation to Toxic Diet, and Extinction of the Carolina Parakeet.

As the only endemic neotropical parrot to have recently lived in the northern hemisphere, the Carolina parakeet (Conuropsis carolinensis) was an iconic North American bird. The last surviving specimen died in the Cincinnati Zoo in 1918 [1]. The cause of its extinction remains contentious: besides excessive mortality associated to habitat destruction and active hunting, their survival could have been negatively affected by its range having become increasingly patchy [2] or by the exposure to poultry pathogens [3, 4]. In addition, the Carolina parakeet showed a predilection for cockleburs, an herbaceous plant that contains a powerful toxin, carboxyatractyloside, or CAT [5], which did not seem to affect them but made the birds notoriously toxic to most predators [3]. To explore the demographic history of this bird, we generated the complete genomic sequence of a preserved specimen held in a private collection in Espinelves (Girona, Spain), as well as of a close extant relative, Aratinga solstitialis. We identified two non-synonymous genetic changes in two highly conserved proteins known to interact with CAT that could underlie a specific dietary adaptation to this toxin. Our genomic analyses did not reveal evidence of a dramatic past demographic decline in the Carolina parakeet; also, its genome did not exhibit the long runs of homozygosity that are signals of recent inbreeding and are typically found in endangered species. As such, our results suggest its extinction was an abrupt process and thus likely solely attributable to human causes.

The VraSR regulatory system contributes to virulence in Streptococcus suis via resistance to innate immune defenses.

Streptococcus suis is a highly invasive pathogen that can cause sepsis and meningitis in pigs and humans. However, we have limited understanding of the mechanisms S. suis uses to evade innate immunity. To investigate the involvement of the two-component signal transduction system of S. suis in host immune defense, we examined the expression of 15 response regulators of S. suis following stimulation with polymorphonuclear leukocytes (PMNs). We found that several response regulators were significantly up-regulated including vraR. Thus, we constructed an isogenic deletion mutant of vraSR genes in S. suis and demonstrated VraSR promotes both bacterial survival in human blood and resistance to human PMN-mediated killing. The VraSR mutant was more susceptible to phagocytosis by human PMNs and had greater sensitivity to oxidant and lysozyme than wild-type S. suis. Furthermore, in vitro findings and in vivo evidence from a mouse infection model together strongly demonstrate that ΔvraSR had greatly attenuated virulence compared with wild-type S. suis. Collectively, our data reveal that VraSR is a critical regulatory system that contributes to the survival of S. suis and its ability to defend against host innate immunity.

[Application of quality by design in granulation process for ginkgo leaf tablet (⠣)： influence and control of raw materials' quality variation].

Raw materials' quality variation could affect the quality consistency of product and the clinical efficacy. In this paper, the high shear wet granulation (HSWG) process of the ginkgo leaf tablet was taken as the research object. Ginkgo biloba extracts and excipients microcrystalline cellulose collected from various sources and batches were used to simulate raw materials' quality variation. Real-time torque was recorded to analyze the viscosity of the wetting mass, and then by combining with physical fingerprint, the impact of physical quality variation of powders on granule properties could be investigated. Based on regime map thesis, whether the granules' nucleation mode was in mechanical dispersion regime was determined by calculating dimensionless parameters, which would lead to the unstable output in considerations of granule yield ratio and particle size distribution (PSD) curve. The orthogonal partial least square (OPLS) model was adopted to build the relationship between the micromeritic properties and the mediangranule size (D50) of Ginkgo biloba granules and then the critical material attributes (CMAs) were screened by variable importance in the projection (VIP) indexes. The results demonstrated that the properties of powders including hygroscopicity, angle of repose, Hausner ratio, Carr index, D10 and loss on drying affected the granule size. Besides, Ginkgo biloba granules were compressed into tablets. In view of tensile strength analysis, the raw materials' quality variation did not result in decrease of tensile strength of the ginkgo leaf tablets. The design space of critical quality attributes (CQAs) and the process design space which could cope with raw materials' quality variation were proved to be robust..

The manganese efflux system MntE contributes to the virulence of Streptococcus suis serotype 2.

Manganese is an essential micronutrient to bacteria and plays an important role in bacterial physiology. However, an excess of manganese is extremely deleterious to the cell. The manganese efflux system is used to control intracellular manganese levels by some bacteria. In this study, we have identified a cation efflux family protein (MntE) that functions as a manganese export system in Streptococcus suis serotype 2. To investigate the role of mntE in S. suis 2, a mntE deletion mutant (ΔmntE) and the corresponding complementation strain (CΔmntE) were constructed. ΔmntE displayed similar growth compared to the wild-type and complementation strains under normal growth conditions, but was defective in medium supplemented with high concentrations of manganese. In addition, the mutant was more sensitive to oxidative stress conferred by diamide. Using a competitive-infection assay in the murine infection model, we demonstrated for the first time that MntE is involved in the virulence of S. suis 2. Collectively, our data indicate that manganese homeostasis controlled by the manganese efflux system MntE is important for the pathogenesis of S. suis 2.

Identification of four type II toxin-antitoxin systems in Actinobacillus pleuropneumoniae.

Toxin-antitoxin (TA) systems are small genetic elements that are widely prevalent in the genomes of bacteria and archaea. These modules have been identified in various bacteria and proposed to play an important role in bacterial physiology and virulence. However, their presence in the genomes of Actinobacillus species has received no attention. In this study, we describe the identification of four type II TA systems in Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia. Reverse transcription PCR analysis revealed that the genes encoding the toxin and antitoxin are co-transcribed. Overexpression of each toxin inhibited the growth of Escherichia coli, and the toxic effect could be counteracted by its cognate antitoxin. The pull-down experiments demonstrated that each toxin interacts with its cognate antitoxin in vivo. The promoter activity assays showed that each antitoxin could autoregulate either positively or negatively the TA operon transcription. In addition, the APJL_0660/0659 TA system is present in half of the detected serovars of A. pleuropneumoniae, while the others are present in all. Collectively, we identified four type II TA systems in A. pleuropneumoniae, and this study has laid the foundation for further functional study of these TA systems.

Contribution of NADH oxidase to oxidative stress tolerance and virulence of Streptococcus suis serotype 2.

Streptococcus suis is a major swine and zoonotic pathogen that causes severe infections. Previously, we identified 2 Spx regulators in S. suis, and demonstrated that SpxA1 affects oxidative stress tolerance and virulence. However, the mechanism behind SpxA1 function remains unclear. In this study, we targeted 4 genes that were expressed at significantly reduced levels in the spxA1 mutant, to determine their specific roles in adaptation to oxidative stress and virulence potential. The Δnox strain exhibited impaired growth under oxidative stress conditions, suggesting that NADH oxidase is involved in oxidative stress tolerance. Using murine and pig infection models, we demonstrate for the first time that NADH oxidase is required for virulence in S. suis 2. Furthermore, the enzymatic activity of NADH oxidase has a key role in oxidative stress tolerance and a secondary role in virulence. Collectively, our findings reveal that NADH oxidase plays an important part in SpxA1 function and provide a new insight into the pathogenesis of S. suis 2.

Formate-tetrahydrofolate ligase is involved in the virulence of Streptococcus suis serotype 2.

Streptococcus suis is an emerging zoonotic pathogen that causes severe infections in pigs and humans. However, the pathogenesis of S. suis remains unclear. The present study targeted a putative virulence-associated factor (fhs, encoding the formate-tetrahydrofolate ligase) of S. suis. To investigate the role of fhs in the virulence potential of S. suis serotype 2, an fhs deletion mutant (Δfhs) and the corresponding complementation strain (CΔfhs) were generated. The Δfhs mutant displayed similar growth compared to that of the wild-type and complementation strains. Using murine and pig infection models, we demonstrated for the first time that the formate-tetrahydrofolate ligase is required for the full virulence of S. suis 2. Our findings provide a new insight into the pathogenesis of S. suis 2.