UBE2C promotes the proliferation of acute myeloid leukemia cells through PI3K/AKT activation.

This study aims to investigate the role and mechanism of tubiquitin-conjugating enzyme E2 C (UBE2C) in acute myeloid leukemia (AML). Initially, UBE2C expression in leukemia was analyzed using the Cancer Genome Atlas database. Further, we silenced UBE2C expression using small-hairpin RNA (sh-RNA). UBE2C expression was detected via the quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and Western blot analysis. Apoptotic events and reactive oxygen species (ROS) levels were detected by flow cytometry. A xenograft model of leukemia cells were established, and the protein levels of UBE2C, KI-67, and cleaved-caspase 3 were detected by immunohistochemistry. We reported an overexpression of UBE2C in leukemia patients and cell lines (HL60, THP-1, U937, and KG-1 cells). Moreover, a high expression level of UBE2C was correlated with a dismal prognosis in AML patients. UBE2C knockdown inhibited the viability and promoted apoptosis in AML cells by regulating the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) signaling pathway. Furthermore, UBE2C knockdown increased cellular Fe2+ and ROS levels, and enhanced erastin-induced ferroptosis in a proteasome-dependent manner. UBE2C knockdown also suppressed the tumor formation of AML cells in the mouse model. In summary, our findings suggest that UBE2C overexpression promotes the proliferation and inhibits ferroptosis in AML cells by activating the PI3K/AKT pathway.

Rearranged Homoadamantane-Type Polycyclic Polyprenylated Acylphloroglucinols from Hypericum pseudohenryi.

Hypseudohenones A-C (1-3), the first rearranged homoadamantane-type polycyclic polyprenylated acylphloroglucinols, were isolated from Hypericum pseudohenryi. Their structures with an unprecedented tricyclo[4.3.1.13,8]undecane-2,4,10-trione core were determined by spectroscopic analysis, quantum-chemical calculations, and X-ray crystallography. A method for determining the relative configuration at C-3 was established by the peak shape of H-28 or J-value of H-3/H-28. Moreover, 2-3 exhibited significant AChE inhibitory activity, and the interactions of 2-3 with AChE were evaluated by molecular docking.

The spatial changes of China's environmental efficiency and driving factors from the perspective of circular economy.

This paper mainly uses the super-efficiency EBM model to measure the environmental efficiency of 30 provinces in China from 2005 to 2019, utilizes the Theil index to analyze the degree of differentiation, and investigate the stochastic convergence of environmental efficiency in different regions. At the same time, it focuses on exploring the direction, intensity, and changing trend of the internal driving factors of environmental efficiency including fiscal decentralization and tax competition, so as to measure and show the overall situation of circular economy development. The research results show that (1) from a national perspective, environmental efficiency shows a pattern of gradual convergence from east to west and from coast to inland. There is a significant stepped regional imbalance in the development level of circular economy in the eastern coastal areas and the central, western inland areas. (2) The differences in environmental efficiency among the four major economic regions were apparently significant while the differences inside each region itself were relatively minor, although in a trend of being gradually widened. There are differences in the development level of circular economy in different regions or within the same region. (3) The inter-provincial efficiency in the eastern, western and northeastern zones maintained relatively stable, while the inter-provincial differences in the central region were expanding. The environmental deficit problem caused by economic development has been alleviated and the basic development model of circular economy has been initially established. (4) Economic development has played a positive role in improving the environmental efficiency of the region. But the resident consumption level inhibited the improvement of the environmental efficiency level of the surrounding areas. The conclusion of this paper can provide a macroscopic reference for the government in finding effective countermeasures to improve environmental efficiency.

Ultrasound combined with glial cell line-derived neurotrophic factor-loaded microbubbles for the targeted treatment of drug addiction.

Drug addiction is a serious problem globally, recently exacerbated by the COVID-19 pandemic. Glial cell-derived neurotrophic factor (GDNF) is considered a potentially effective strategy for the treatment of addiction. Previous animal experiments have proven that GDNF has a good therapeutic effect on drug addiction, but its clinical application is limited due to its poor blood-brain barrier (BBB) permeability. Low-frequency focused ultrasound, combined with microbubbles, is a non-invasive and reversible technique for locally-targeted BBB opening. In the present study, magnetic resonance imaging-guided low-frequency focused ultrasound, combined with GDNF microbubbles, was used to target BBB opening in the ventral tegmental area (VTA) region. The effects of GDNF on morphine-induced conditioned place preference (CPP) and acute withdrawal symptoms in rats after a partially opened BBB were evaluated by behavioral observation. Western blot was used to detect changes in tyrosine hydroxylase (TH) expression levels in the VTA region after different treatments, and high performance liquid chromatography was used to detect the changes in monoamine neurotransmitter content. The results showed that ultrasound combined with GDNF microbubbles targeted and opened the BBB in the VTA region, and significantly increased GDNF content, destroyed morphine-induced CPP, and reduced the withdrawal symptoms of morphine addiction in rats. Furthermore, the up-regulation of TH expression and the increase of norepinephrine and dopamine content induced by morphine were significantly reversed, and the increase of 5-hydroxytryptamine content was partially reversed. Therefore, ultrasound combined with GDNF microbubbles to target and open the BBB can effectively increase the content of central GDNF, thus playing a therapeutic role in morphine addiction. Our study provides a new approach to locally open the BBB and target delivery of neurotrophic factors, such as GDNF, to treat brain diseases like addiction.

Corilagin prevents non-alcoholic fatty liver disease via improving lipid metabolism and glucose homeostasis in high fat diet-fed mice.

Non-alcoholic fatty liver disease (NAFLD) has been considered to be one of the most common chronic liver diseases. However, no validated pharmacological therapies have been officially proved in clinic due to its complex pathogenesis. The purpose of this study was to examine the protective effects of Corilagin (referred to Cori) against NAFLD in mice under a high fat diet (HFD) condition. Mice were fed either a normal control diet (NCD) or HFD with or without Cori (5 or 10 mg/kg body weight) for 15 weeks. In our results, Cori treatment significantly attenuated HFD-induced hepatic steatosis, high NAFLD activity score (NAD) and liver injury. Consistently, Cori treatment remarkably alleviated HFD-induced hepatic lipid accumulation (e.g., triglycerides (TG) and total cholesterol (TC) contents in liver), and improved plasma lipid concentrations (e.g., plasma TG, TC, low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c)). Moreover, Cori treatment ameliorated NAFLD associated metabolic disorders such as glucose intolerance and insulin resistance in HFD-fed mice. Additionally, Cori treatment dramatically changed HFD-induced liver gene expression profiles, and identified overlapped differentially expressed genes (DEGs) between NCD vs. HFD group and HFD vs. HCR (high fat diet plus treatment with Cori) group. With these DEGs, we observed a marked enrichment of Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, which were closely associated with the metabolic balance in liver. Particularly, we found several potential hub proteins against NAFLD development with analyses of protein-protein interaction (PPI) network and qPCR assays. Collectively, our results revealed the important protective effects of Cori against the progress of NAFLD, which was probably mediated through improving dysregulated lipid metabolism and insulin resistance in HFD-fed mice. Additionally, Cori-dependent overlapped DEGs might serve as a featured NAFLD-associated gene expression signature for the diagnosis, treatment, as well as drug discovery and development of NAFLD in the near future.

Non-invasive, targeted, and non-viral ultrasound-mediated brain-derived neurotrophic factor plasmid delivery for treatment of autism in a rat model.

Autism has clinical manifestations such as social interaction disorder, speech and intellectual development disorder, narrow interest range, and stereotyped and repetitive behavior, all of which bring considerable economic and mental burden to society and families, and represent a public health problem requiring urgent attention. Brain-derived neurotrophic factor (BDNF) plays an important role in supporting survival, differentiation, growth, and synapse formation of neurons and participates in the plasticity of nerves. However, it is difficult for BDNF to penetrate the blood-brain barrier (BBB) due to its large molecular weight. Low-frequency focused ultrasound (FUS) combined with microbubbles (MBs) has been demonstrated to be a promising method for opening the BBB non-invasively, transiently, and locally. Here, we studied the therapeutic effect of FUS combined with BDNF plasmid-loaded cationic microbubbles (BDNFp-CMBs) in a rat model of autism. BDNF-CMBs were prepared and the transfection efficiency of FUS combined with BDNF-CMBs was tested in vitro. A rat model of autism was established from the juvenile male offspring of Sprague-Dawley (SD) pregnant rats treated with sodium valproate (VPA) solution through intraperitoneal injection. The autism rats were randomized into three groups: the VPA group, which received no treatment, the BDNFp group, which was treated by injection of BDNFp, and the FUS + BDNFp-CMBs group, which was administered FUS combined with BDNFp-CMBs. Age-matched normal rats served as the control group (Con). Following treatment, stereotyped, exploratory, and social-behavioral tests were performed on the animals in each group. The rat brains were then collected for subsequent histological examination, and the changes in synaptic structures in the prefrontal cortex (PFC) were detected under transmission electron microscopy. The results showed that the constructed BDNFp could be loaded onto CMBs with high loading efficiency. The BDNFp-CMBs prepared in this study showed good stability in vivo. FUS combined BDNFp-CMBs could effectively and non-invasively open the BBB of rats. The stereotyped, exploratory, and social behaviors of the FUS + BDNFp-CMBs group were significantly improved. Compared to the VPA group, the abnormality of neuronal morphology and number in the PFC of the FUS + BDNFp-CMBs was alleviated to a certain extent and was accompanied by restoration of the damaged synapses in the encephalic region. Our work demonstrates the positive therapeutic effect of BDNF delivered by FUS non-invasively across the BBB into the PFC in a rat model of autism, offering a potential strategy for treating autism.

Therapeutic Effect of Ultrasound Combined With Porous Lipid Clioquinol/PLGA Microbubbles on Ferroptosis in HL-1 Cardiac Cell Induced by Isoproterenol Attack.

In recent years, studies have shown a close relationship between cardiomyocyte death and ferroptosis. Clioquinol (CQ) can inhibit ferroptosis. Porous lipid-poly (lactic-co-glycolic acid) (PLGA) microbubbles (MBs) were prepared by double emulsification (W1/O/W2) using 1,2-dioctadecanoyl-sn-glycero-3-phophocholine and PLGA as raw materials. Porous lipid-PLGA MBs were used as carriers to prepare CQ/PLGA MBs containing CQ. CQ/PLGA had the advantages of high drug loading, good biocompatibility, and sustained release. Our results showed that CQ/PLGA improved the effect of CQ and reduced its cytotoxicity. Under low-frequency ultrasound with certain parameters, CQ/PLGA showed steady-state cavitation, which increased the membrane permeability of mouse cardiomyocyte HL-1 to a certain extent and further prevented the process of ferroptosis in mouse cardiomyocyte HL-1.

Ultrasound-triggered drug delivery for glioma therapy through gambogic acid-loaded nanobubble-microbubble complexes.

Glioma is one of the most common primary brain tumors. Gambogic acid (GA) is widely used in tumor chemotherapy. However, GA has poor water solubility, low bioavailability, and difficult permeability across the blood-brain barrier (BBB), leading to poor efficacy against brain tumors. In our study, we developed negatively charged GA-loaded PLGA nanobubbles [GA/poly(lactic-co-glycolic acid) (PLGA)] and conjugated them onto the surface of cationic lipid microbubbles (CMBs) through electrostatic interactions. The resulting GA/PLGA-CMB complex was characterized for its particle size, distribution, drug encapsulation efficiency, and ultrasound imaging property, revealing a high drug encapsulation efficiency and excellent contrast imaging capability. Importantly, significantly enhanced GA delivery into the brain could be observed after the intravenous administration of GA/PLGA-CMBs combined with low-intensity focused ultrasound (FUS) due to the cavitation from CMBs, which mediated blood-brain barrier (BBB) opening. Taking advantage of the opened BBB, GA/PLGA nanobubbles could be delivered into the tumor. Then, the second FUS irradiation at higher energy was used to induce the cavitation of GA/PLGA nanobubbles, producing the second cavitation on tumor cells, significantly enhancing the ability of GA to enter tumor cells and inhibit tumor growth inhibition efficacy.

A Gambogic Acid-Loaded Delivery System Mediated by Ultrasound-Targeted Microbubble Destruction: A Promising Therapy Method for Malignant Cerebral Glioma.

Background: The blood-brain barrier (BBB) inhibits the delivery of macromolecular chemotherapeutic drugs to brain tumors, leading to low utilization rates and toxic side effects to surrounding tissues and organs. Ultrasonic targeted microbubble destruction (UTMD) technology can open the BBB, leading to a new type of drug delivery system with particular utility in glioma. Purpose: We have developed a new type of drug-loaded microbubble complex based on poly(lactic-co-glycolic acid) (PLGA) that targets gambogic acid (GA) to the area of brain tumors through UTMD. Methods: GA/PLGA nanoparticles were prepared by the double emulsification method, and cationic microbubbles (CMBs) were prepared by a thin film hydration method. The GA/PLGA-CMB microbubble complex was assembled through electrostatic attractions and was characterized chemically. The anti-glioblastoma effect of GA/PLGA-CMB combined with focused ultrasound (FUS) was evaluated by biochemical and imaging assays in cultured cells and model mice. Results: GA/PLGA-CMB combined with FUS demonstrated a significant inhibitory effect on glioblastoma cell lines U87 and U251 as compared with controls (P<0.05). Tumor access and imaging analyses demonstrated that administration of GA/PLGA-CMBs combined with FUS can open the BBB and target the treatment of glioblastoma in a mouse model, as compared with control groups (P<0.05). Conclusion: The combination of PLGA-CMB with FUS provides an effective and biocompatible drug delivery system, and its application to the delivery of GA in a mouse glioblastoma model was successful.

A time-course study of microglial activation and dopaminergic neuron loss in the substantia nigra of mice with paraquat-induced Parkinson's disease.

Activated microglia play an active role in the pathogenesis of PD and paraquat (PQ) induces PD. The study was to understand the time relationship between microglial activation and dopaminergic neuron loss in the substantia nigra (SN) of PQ-induced PD mice. Male C57BL/6 mice were injected intraperitoneally with PQ, twice a week for six weeks. Some mice underwent behavioral assessments each week and were sacrificed for SN tissues, in which histopathological analysis, dopaminergic neuron loss, microglial activation and phenotypic characteristics were evaluated. The results showed that motor retardation, coordination disorders and limb stiffness occurred four weeks after PQ exposure, as well as the degeneration and loss of dopaminergic neurons in the SN. Activated microglia and increased CD68 expression appeared two weeks after PQ exposure in time-dependent manners. Increased CD86 and decreased CD206 expression were observed four weeks after PQ exposure, accompanied by increased TNF-α and IL-6 levels and decreased IL-10 and TGF-ß levels. These results indicate that PQ can activate microglia in vivo, and microglial activation precedes neuronal loss in the SN. Activated microglia are characterized by mixed M1/M2 polarization in the early stage and M1 polarization in the late stage of PQ-induced PD development.

Purification of biflavonoids from Selaginelladoe derleinii Hieron by special covalent organic polymers material.

Herein, a novel covalent organic polymers (COP) material based on acylhydrazone bond (AB-COP) was prepared as an efficient extraction material for enriching natural medicine biflavonoids from Selaginella doederleinii Hieron. The obtained AB-COP structure was characterized in detail. And it was the first time to investigate the effect of AB-COP on the adsorption of biflavonoids. The effects of initial concentration of solution, adsorption temperature, solid-liquid ratio, adsorption time on the adsorption of biflavonoids were studied. In addition, adsorption kinetic model, adsorption thermodynamic model and density functional theory (DFT) were also investigated to evaluate the adsorption mechanism. At the same time, the static desorption and reusability of AB-COP were investigated. Finally, the dynamic enrichment effect of AB-COP for biflavonoids was investigated. The results showed that AB-COP was successfully synthesized by Fourier transform infrared spectroscopy (FT-IR), solid state nuclear magnetism (NMR), X-ray diffraction (XRD), thermogravimetric analysis (TG), scanning electron microscopy (SEM), laser particle size analysis and Brunner Emmet Teller (BET) specific surface area test. The optimized adsorption parameters of AB-COP were initial concentration of 0.5 mg/mL, temperature of 45 °C, solid-liquid ratio of 10:10 (mg/mL), adsorption time of 60 min. The Langmuir adsorption isotherm could effectively describe the adsorption process, the pseudo-secondary adsorption model could accurately explain the adsorption mechanism, and the DFT calculations revealed that the interaction forces of AB-COP and biflavonoids were π-π stacking and hydrogen bonding. In addition, AB-COP successfully resolved biflavonoids through urea-methanol (1.3 mol/L), and the material can be reused at least four times. Finally, the solid phase extraction (SPE) chromatographic column prepared by AB-COP was successfully applied to the enrichment of biflavonoids from S. doederleinii, and the effect was significantly better than traditional chromatography materials, andthis method was also successfully applied to the enrichment of flavonoids in other plant extracts including Flos sophorae, Pericarpium viride, Lophatheri herba, Herba cuscutae. These results provide references for further purification of bioactive ingredients from plant extracts by using AB-COP.

Acoustic Beam Mapping for Guiding HIFU Therapy In Vivo Using Sub-Therapeutic Sound Pulse and Passive Beamforming.

OBJECTIVE: Although HIFU has been successfully applied in various clinical applications in the past two decades for the ablation of many types of tumors, one bottleneck in its wider applications is the lack of a reliable and affordable strategy to guide the therapy. This study aims at estimating the therapeutic beam path at the pre-treatment stage to guide the therapeutic procedure. METHODS: An incident beam mapping technique using passive beamforming was proposed based on a clinical HIFU system and an ultrasound imaging research system. An optimization model was created to map the cross-like beam pattern by maximizing the total energy within the mapped area. This beam mapping technique was validated by comparing the estimated focal region with the HIFU-induced actual focal region (damaged region) through simulation, in-vitro, ex-vivo and in-vivo experiments. RESULTS: The results of this study showed that the proposed technique was, to a large extent, tolerant of sound speed inhomogeneities, being able to estimate the focal location with errors of 0.15 mm and 0.93 mm under in-vitro and ex-vivo situations respectively, and slightly over 1 mm under the in-vivo situation. It should be noted that the corresponding errors were 6.8 mm, 3.2 mm, and 9.9 mm respectively when the conventional geometrical method was used. CONCLUSION: This beam mapping technique can be very helpful in guiding the HIFU therapy and can be easily applied in clinical environments with an ultrasound-guided HIFU system. SIGNIFICANCE: The technique is safe and can potentially be adapted to other ultrasound-related beam manipulating applications.

Efficacy and safety of CDK4/6 inhibitors combined with endocrine therapy versus endocrine therapy alone in hormone receptor-positive, HER2-negative, advanced breast cancer: a systematic review and meta-analysis.

BACKGROUND: In previous studies on the application of cyclin-dependent kinase 4/6 (CDK4/6) inhibitors combined with endocrine therapy in advanced breast cancer, the outcomes of overall survival (OS) were inconsistent. This systematic review and meta-analysis aimed to further evaluate the clinical efficacy and safety of CDK4/6 inhibitors combined with endocrine therapy on patients with hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. METHODS: Randomized controlled trials (RCTs) comparing CDK4/6 inhibitors plus endocrine therapy and endocrine therapy alone in patients with HR-positive and HER2-negative advanced breast cancer were searched in the databases of PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), WANFANG and China Science and Technology Journal Database (VIP) up to November 2022. Hazard ratios (HRs) and confidence intervals (CI) of OS, progression-free survival (PFS), the time from randomization to the first recorded disease progression while the patient was receiving next-line therapy or death from any cause (PFS2), time to first subsequent chemotherapy after discontinuation (TTC), and objective response rate (ORR), clinical benefit rate (CBR), safety indicators were extracted. Stata 14.0 software was used for meta analysis and the Cochrane risk-of-bias tool 2.0 was used to evaluate the bias risk. RESULTS: A total of 9 RCTs with 4,920 participants were included. The addition of CDK4/6 inhibitors to endocrine therapy significantly prolonged OS (HR 0.76; 95% CI: 0.69-0.84; P<0.001), regardless of the application in first-line and second-line treatment, compared with endocrine therapy alone. Similar benefit was observed in PFS (HR 0.56; 95% CI: 0.52-0.60; P<0.001). Moreover, the CDK4/6 inhibitors group improved results of ORR [relative risk (RR) 1.43; 95% CI: 1.27-1.62; P<0.001], CBR (RR 1.24; 95% CI: 1.08-1.41; P<0.01 and RR 1.11; 95% CI: 1.06-1.18; P<0.001), PFS2 (HR 0.68; 95% CI: 0.60-0.76; P<0.001) and TTC (HR 0.65; 95% CI: 0.58-0.72; P<0.001). One of the included RCTs had performance bias. Publication bias was not significant. CONCLUSIONS: CDK4/6 inhibitors combined with endocrine therapy effectively prolong OS, PFS, PFS2, and TTC, and also improve ORR and CBR in patients with HR-positive, HER2-negative advanced breast cancer, and the safety was within the controllable range.

Cardioprotective effects of Amentoflavone by suppression of apoptosis and inflammation on an in vitro and vivo model of myocardial ischemia-reperfusion injury.

Inflammation modulation is currently considered a promising therapeutic strategy to counteract the burden of cardiovascular disease. Amentoflavone (AME) is a natural biflavone with two apigenin molecules that, possess promising anti-inflammatory, anti-oxidative, and anti-cancer properties. In the present study, we aimed to investigate the effects of AME on myocardial ischemia-reperfusion injury in vivo and in vitro, and to elucidate the underlying mechanism. Our results showed that AME significantly reduced the levels of LDH, CK-MB, IL-6, IL-1ß, and TNF-α after hypoxia (H) 12 h/reoxygenation (R) 4 h treatment, and significantly increased the cell survival rate of H9c2 cardiomyocytes induced by H/R and inhibited their apoptosis rate. AME (25, 50, 100 mg·kg-1·d-1, i.g.) or a positive control drug diltiazem (DIZ) (16 mg·kg-1·d-1, i.g.) was used as pretreatment for 7 days; the myocardial ischemia-reperfusion(I/R) model was established. TTC staining results showed that the infarct volume was significantly reduced after AME and DIZ treatment. Oral administration of AME dose-dependently ameliorated I/R injury-induced increase in pro-inflammatory factors (IL-6, IL-1ß, and TNF-α) and levels of LDH and CK-MB. Results of TUNEL and HE staining showed that the I/R model had more induced apoptosis, but could be effectively reduced by pretreatment with AME. After surgery, the heart of the rat was examined via western blotting to detect inflammation-related proteins. Compared with the sham group, the p-AKT in the I/R group was significantly reduced and the content of p-NF-κBp65 was significantly increased. However, these changes could be reversed by AME treatment. DIZ treatment exerted similar beneficial effects in I/R rats as the high dose of AME did. This study highlights the excellent therapeutic potential of AME for managing myocardial ischemia-reperfusion injury.

Effect of Gambogic Acid-Loaded Porous-Lipid/PLGA Microbubbles in Combination With Ultrasound-Triggered Microbubble Destruction on Human Glioma.

Gambogic acid (GA) is a highly effective antitumor agent, and it is used for the treatment of a wide range of cancers. It is challenging to deliver drugs to the central nervous system due to the inability of GA to cross the blood-brain barrier (BBB). Studies have shown that ultrasound-targeted microbubble destruction can be used for transient and reversible BBB disruption, significantly facilitating intracerebral drug delivery. We first prepared GA-loaded porous-lipid microbubbles (GA porous-lipid/PLGA MBs), and an in vitro BBB model was established. The cell viability was detected by CCK-8 assay and flow cytometry. The results indicate that U251 human glioma cells were killed by focused ultrasound (FUS) combined with GA/PLGA microbubbles. FUS combined with GA/PLGA microbubbles was capable of locally and transiently enhancing the permeability of BBB under certain conditions. This conformational change allows the release of GA to extracellular space. This study provides novel targets for the treatment of glioma.

Ultrasound Combined With Microbubbles Loading BDNF Retrovirus to Open BloodBrain Barrier for Treatment of Alzheimer's Disease.

Background: Brain-derived nerve growth factor (BDNF) is a promising effective target for the treatment of Alzheimer's disease (AD). BDNF, which has a high molecular weight, has difficulty in crossing the blood-brain barrier (BBB). The study aimed to prepare microbubbles loading brain-derived nerve growth factor (BDNF) retrovirus (MpLXSN-BDNF), to verify the characteristics of the microbubbles, and to study the therapeutic effect of the microbubbles combined with ultrasound on the opening of the blood-brain barrier in an AD rat model. Methods: 32 adult male SD rats were randomly divided into four groups: control group, ultrasound + pLXSN-EGFP microbubble group (U + MpLXSN-BDNF), ultrasound + pLXSN-BDNF microbubble group, and ultrasound + microbubble + pLXSN-BDNF virus group (U + MpLXSN-BDNF), with eight rats in each group. At the same time, the left hippocampus of rats was irradiated with low-frequency focused ultrasound guided by MRI to open the blood-brain barrier (BBB). The effects of BDNF overexpression on AD rats were evaluated behaviorally before and 1 month after the treatment. The number of acetylcholinesterase (ChAT)-positive cells and the content of acetylcholine (ACh) in brain tissues were determined by immunohistochemistry and high-performance liquid chromatography (HPLC), respectively. IF staining of synaptic spines and Western blot of synaptophysin presented herein detected synaptic density recovery. Results: Signal intensity enhancement at the BBB disruption sites could be observed on the MR images. The behavioral evaluation showed that the times of crossing the original platform in the U + MpLXSN-BDNF group increased significantly after treatment. Immunohistochemistry and HPLC revealed that the number of ChAT-positive neurons and the contents of ACh in the brain were significantly decreased in the treated groups compared with the controls. IF staining of synaptic spines and Western blot data of synaptophysin showed that the U + MpLXSN-BDNF group can recover the synaptic loss better by BDNF supplementation than the other treatment groups. Conclusion: Ultrasound combined with viral microbubbles carrying BDNF can increase the transfection efficiency of brain neurons, promote the high expression of exogenous gene BDNF, and play a therapeutic role in the AD model rats.

MRI-Guided Focused Ultrasound-Induced Blood Brain Barrier Disruption to Deliver Glial Cell Line Derived Neurotropic Factor Proteins into Brain to Treat Rat Depression.

Glial cell line derived neurotropic factor (GDNF) plays a crucial role in the development and maintenance of glial cells, serotonergic and dopaminergic neurons. A positively therapeutic effect has been demonstrated on some animal neurodegenerative diseases. However, the inability to deliver the protein across blood brain barrier (BBB) into damaged brain region limits its clinical application. Here, we developed GDNF-loaded microbubbles (MBs) and achieved a local and precise delivery of GDNF into the brain through MRI-guided focused ultrasound-induced BBB disruption. To demonstrate the therapeutic effect, rat depression model was developed by chronic mild stress treatment. Typical depression behaviors were confirmed. MRI-guided focused ultrasound was used to irradiate the GDNF-loaded MBs. Obvious BBB opening was observed in the treated rat brains and a significant higher GDNF concentration was detected in the ultrasound-treated brain tissues. Behavioral tests demonstrated the increased GDNF could reverse the depressive-like behaviors induced by chronic mild stress, improve the expression of 5-HT 1B receptor and the protein p11, and increase the number of 5-HT or TPH2 immunoreactive neurons. In conclusion, our study provided an effective approach to deliver GDNF proteins into brain to treat rat depression through MRI-guided focused ultrasound-induced destruction of blood-brain barrier.

Attenuation of paraquat-induced inflammation by inhibitors of phosphorylation of mitogen-activated protein kinases in BV2 microglial cells.

Paraquat has dopaminergic neurotoxicity and potentially contributes to Parkinson's disease (PD) as a risk factor. However, the cellular and molecular mechanisms of PQ-induced neurodegeneration have not been clearly elucidated. Studies have shown that PQ induces microglial neuroinflammation through toll-like receptor 4 (TLR4)-nuclear factor-κB pathway, resulting in neuronal cell loss. Mitogen-activated protein kinases (MAPKs) are involved in the production of pro-inflammatory cytokines in microglia, and in this study, the role of MAPKs in PQ-activated microglial inflammation was investigated. Murine BV2 microglial cells were treated with 40 µM of PQ following pretreatment of the cells with selective inhibitor of MAPKs phosphorylation for blockage of the phosphorylation of ERK, JNK and P38, or a specific TLR4 inhibitor for blocking the activation of TLR4. The protein expression of phosphorylated ERK, JNK and p38, and the transcription expression of pro-inflammatory mediators were assessed with Western blotting and qRT-PCR technique, respectively. The results indicated that PQ significantly induced the phosphorylation of ERK, JNK and P38 in microglia, while MAPKs inhibitors suppressed PQ-induced phosphorylation of ERK, JNK and P38, and reduced the transcription level of pro-inflammatory cytokines. PQ-stimulated phosphorylation of ERK, JNK and P38 was also reduced by TLR4 inhibitor. The inhibited intensity in the level of pro-inflammatory cytokine transcription was obviously greater in TLR4 inhibitor + PQ group than in each MAPK inhibitor + PQ group. Taken together, inhibition of MAPKs phosphorylation partially attenuates PQ-induced microglial inflammation, which may become a potential intervention strategy for PQ neurotoxicity.

New Organometallic Tetraphenylethylene⋠Iridium(III) Complexes with Antineoplastic Activity.

Iridium(III) complexes have attracted more and more attention in the past few years because of their potential antineoplastic activity. In this study, four IrIII complexes of the types [(η5 -Cpx )Ir(N^N)Cl]PF6 (complexes 1 and 2) and [Ir(Phpy)2 (N^N)]PF6 (complexes 3 and 4) have been synthesized and characterized. They exhibit potential antineoplastic activity towards A549 cells, especially in the case of complex 1 [IC50 =(3.56±0.5) µm], which was nearly six times as effective as cisplatin [(21.31±1.7) µm]. Additionally, these complexes show some selectivity towards cancer cells over normal cells. They could be transported by serum albumin (binding constants were changed from 0.37×105 to 81.71×105 m-1 ). IrIII complexes 1 and 2 could catalyze the transformation of nicotinamide adenine dinucleotide reduced form (NADH) into NAD+ (turnover numbers 43.2, 11.9] and induce the accumulation of reactive oxygen species, thus confirming their antineoplastic mechanism of oxidation, whereas the cyclometalated complexes 3 and 4 were able to target the lysosome [Pearson co-localization coefficient (PCC)=0.73], cause lysosomal damage, and induce apoptosis. Understanding the mechanism of action would help further structure-activity optimization on these IrIII complexes as emerging cancer therapeutics.

A Rutile TiO2 Electron Transport Layer for the Enhancement of Charge Collection for Efficient Perovskite Solar Cells.

Interfacial charge collection efficiency has demonstrated significant effects on the power conversion efficiency (PCE) of perovskite solar cells (PSCs). Herein, crystalline phase-dependent charge collection is investigated by using rutile and anatase TiO2 electron transport layer (ETL) to fabricate PSCs. The results show that rutile TiO2 ETL enhances the extraction and transportation of electrons to FTO and reduces the recombination, thanks to its better conductivity and improved interface with the CH3 NH3 PbI3 (MAPbI3 ) layer. Moreover, this may be also attributed to the fact that rutile TiO2 has better match with perovskite grains, and less trap density. As a result, comparing with anatase TiO2 ETL, MAPbI3 PSCs with rutile TiO2 ETL delivers significantly enhanced performance with a champion PCE of 20.9 % and a large open circuit voltage (VOC ) of 1.17 V.