A multifunctional biomimetic nanoplatform for image-guideded photothermal-ferroptotic synergistic osteosarcoma therapy.

Much effort has been devoted to improving treatment efficiency for osteosarcoma (OS). However, most current approaches result in poor therapeutic responses, thus indicating the need for the development of other therapeutic options. This study developed a multifunctional nanoparticle, PDA-MOF-E-M, an aggregation of OS targeting, programmed death targeting, and near-infrared (NIR)-aided targeting. At the same time, a multifunctional nanoparticle that utilises Fe-MOFs to create a cellular iron-rich environment and erastin as a ferroptosis inducer while ensuring targeted delivery to OS cells through cell membrane encapsulation is presented. The combination of PDA-MOF-E-M and PTT increased intracellular ROS and LPO levels and induced ferroptosis-related protein expression. A PDA-based PTT combined with erastin showed significant synergistic therapeutic improvement in the anti-tumour efficiency of the nanoparticle in vitro and vivo. The multifunctional nanoparticle efficiently prevents the osteoclasia progression of OS xenograft bone tumors in vivo. Finally, this study provides guidance and a point of reference for clinical approaches to treating OS.

Senktide blocks aberrant RTN3 interactome to retard memory decline and tau pathology in social isolated Alzheimer's disease mice.

Sporadic or late-onset Alzheimer's disease (LOAD) accounts for more than 95% of Alzheimer's disease (AD) cases without any family history. Although genome-wide association studies have identified associated risk genes and loci for LOAD, numerous studies suggest that many adverse environmental factors, such as social isolation, are associated with an increased risk of dementia. However, the underlying mechanisms of social isolation in AD progression remain elusive. In the current study, we found that 7 days of social isolation could trigger pattern separation impairments and presynaptic abnormalities of the mossy fibre-CA3 circuit in AD mice. We also revealed that social isolation disrupted histone acetylation and resulted in the downregulation of 2 dentate gyrus (DG)-enriched miRNAs, which simultaneously target reticulon 3 (RTN3), an endoplasmic reticulum protein that aggregates in presynaptic regions to disturb the formation of functional mossy fibre boutons (MFBs) by recruiting multiple mitochondrial and vesicle-related proteins. Interestingly, the aggregation of RTN3 also recruits the PP2A B subunits to suppress PP2A activity and induce tau hyperphosphorylation, which, in turn, further elevates RTN3 and forms a vicious cycle. Finally, using an artificial intelligence-assisted molecular docking approach, we determined that senktide, a selective agonist of neurokinin3 receptors (NK3R), could reduce the binding of RTN3 with its partners. Moreover, application of senktide in vivo effectively restored DG circuit disorders in socially isolated AD mice. Taken together, our findings not only demonstrate the epigenetic regulatory mechanism underlying mossy fibre synaptic disorders orchestrated by social isolation and tau pathology but also reveal a novel potential therapeutic strategy for AD.

Tau pathology epigenetically remodels the neuron-glial cross-talk in Alzheimer's disease.

The neuron-glia cross-talk is critical to brain homeostasis and is particularly affected by neurodegenerative diseases. How neurons manipulate the neuron-astrocyte interaction under pathological conditions, such as hyperphosphorylated tau, a pathological hallmark in Alzheimer's disease (AD), remains elusive. In this study, we identified excessively elevated neuronal expression of adenosine receptor 1 (Adora1 or A1R) in 3×Tg mice, MAPT P301L (rTg4510) mice, patients with AD, and patient-derived neurons. The up-regulation of A1R was found to be tau pathology dependent and posttranscriptionally regulated by Mef2c via miR-133a-3p. Rebuilding the miR-133a-3p/A1R signal effectively rescued synaptic and memory impairments in AD mice. Furthermore, neuronal A1R promoted the release of lipocalin 2 (Lcn2) and resulted in astrocyte activation. Last, silencing neuronal Lcn2 in AD mice ameliorated astrocyte activation and restored synaptic plasticity and learning/memory. Our findings reveal that the tau pathology remodels neuron-glial cross-talk and promotes neurodegenerative progression. Approaches targeting A1R and modulating this signaling pathway might be a potential therapeutic strategy for AD.

miR-135a-5p mediates memory and synaptic impairments via the Rock2/Adducin1 signaling pathway in a mouse model of Alzheimer's disease.

Aberrant regulation of microRNAs (miRNAs) has been implicated in the pathogenesis of Alzheimer's disease (AD), but most abnormally expressed miRNAs found in AD are not regulated by synaptic activity. Here we report that dysfunction of miR-135a-5p/Rock2/Add1 results in memory/synaptic disorder in a mouse model of AD. miR-135a-5p levels are significantly reduced in excitatory hippocampal neurons of AD model mice. This decrease is tau dependent and mediated by Foxd3. Inhibition of miR-135a-5p leads to synaptic disorder and memory impairments. Furthermore, excess Rock2 levels caused by loss of miR-135a-5p plays an important role in the synaptic disorder of AD via phosphorylation of Ser726 on adducin 1 (Add1). Blocking the phosphorylation of Ser726 on Add1 with a membrane-permeable peptide effectively rescues the memory impairments in AD mice. Taken together, these findings demonstrate that synaptic-related miR-135a-5p mediates synaptic/memory deficits in AD via the Rock2/Add1 signaling pathway, illuminating a potential therapeutic strategy for AD.

TRIM47 promotes malignant progression of renal cell carcinoma by degrading P53 through ubiquitination.

BACKGROUND: Renal cell carcinoma (RCC) is one of the most common malignant tumors originating from the renal parenchymal urinary epithelial system. Tripartite motif 47 (TRIM47) is a member of the TRIM family proteins, which has E3 ligase activity and has been demonstrated to be involved in the occurrence and prognosis of many tumors. The main purpose of this study is to explore the role and potential mechanism of TRIM47 in promoting malignant biological behavior of RCC. MATERIALS AND METHODS: TRIM47 mRNA and protein levels in human renal cancer and paired normal adjacent tissues were detected by qRT-PCR and Western blot. The effects of TRIM47 knockdown and overexpression in renal cell carcinoma cells on cell proliferation, invasion and xenograft tumor growth in nude mice were analyzed. The molecular mechanism was explored by mass spectrometric exploration,Western blot and immunoprecipitation assays. RESULTS: TRIM47 promoted RCC cell proliferation in vitro and in vivo as an oncogene. Mechanistically, TRIM47 exerted an E3 ligase activity by interacting with P53 protein to increase its ubiquitination and degradation, which further promoted the malignant biological behavior of RCC. CONCLUSIONS: Our study demonstrated that the TRIM47-P53 axis played a functional role in RCC progression and suggested a potential therapeutic target for RCC.

Loss of ferroportin induces memory impairment by promoting ferroptosis in Alzheimer's disease.

Iron homeostasis disturbance has been implicated in Alzheimer's disease (AD), and excess iron exacerbates oxidative damage and cognitive defects. Ferroptosis is a nonapoptotic form of cell death dependent upon intracellular iron. However, the involvement of ferroptosis in the pathogenesis of AD remains elusive. Here, we report that ferroportin1 (Fpn), the only identified mammalian nonheme iron exporter, was downregulated in the brains of APPswe/PS1dE9 mice as an Alzheimer's mouse model and Alzheimer's patients. Genetic deletion of Fpn in principal neurons of the neocortex and hippocampus by breeding Fpnfl/fl mice with NEX-Cre mice led to AD-like hippocampal atrophy and memory deficits. Interestingly, the canonical morphological and molecular characteristics of ferroptosis were observed in both Fpnfl/fl/NEXcre and AD mice. Gene set enrichment analysis (GSEA) of ferroptosis-related RNA-seq data showed that the differentially expressed genes were highly enriched in gene sets associated with AD. Furthermore, administration of specific inhibitors of ferroptosis effectively reduced the neuronal death and memory impairments induced by Aß aggregation in vitro and in vivo. In addition, restoring Fpn ameliorated ferroptosis and memory impairment in APPswe/PS1dE9 mice. Our study demonstrates the critical role of Fpn and ferroptosis in the progression of AD, thus provides promising therapeutic approaches for this disease.

Tau overexpression impairs neuronal endocytosis by decreasing the GTPase dynamin 1 through the miR-132/MeCP2 pathway.

Tauopathies are a class of neurodegenerative diseases that are characterized by pathological aggregation of tau protein, which is accompanied by synaptic disorders. However, the role of tau in endocytosis, a fundamental process in synaptic transmission, remains elusive. Here, we report that forced expression of human tau (hTau) in mouse cortical neurons impairs endocytosis by decreasing the level of the GTPase dynamin 1 via disruption of the miR-132-MeCP2 pathway; this process can also be detected in the brains of Alzheimer's patients and hTau mice. Our results provide evidence for a novel role of tau in the regulation of presynaptic function.

HIF1/2α mediates hypoxia-induced LDHA expression in human pancreatic cancer cells.

Glycolysis is a typical conduit for energy metabolism in pancreatic cancer (PC) due to the hypoxic microenviroment. Lactate dehydrogenase A (LDHA) catalyzes the conversion of pyruvate to lactate and is considered to be a key checkpoint of anaerobic glycolysis. The aim of the present study was to explore the mechanism of interactions between hypoxia, HIF-1/2α and LDHA, and the function of LDHA on PC cells by analyzing 244 PC and paratumor specimens. It was found that LDHA was over-expressed and related to tumor stages. The result of in vitro study demonstrated that hypoxia induced LDHA expression. To explore the relationship between HIF and LDHA, chromatin immunoprecipitation assay and luciferase assay were performed. The result showed that HIF-1/2α bound to LDHA at 89bp under the hypoxic condition. Furthermore, knockdown of endogenous HIF-1α and HIF-2α decreased the LDHA expression even in the hypoxic condition, which was accompanied with a significant decrease in lactate production and glucose utilization (p < 0.01). Immunofluorescence in the 244 specimens showed that HIF-1/2α was over-expressed and associated with LDHA over-expression (p < 0.0001). Forced expression of LDHA promoted the growth and migration of PC cells, while knocking down the expression of LDHA inhibited the cell growth and migration markedly. In summary, the present study proved that HIF1/2α could activate LDHA expression in human PC cells, and high expression of LDHA promoted the growth and migration of PC cells.

[Testbed-Based Exhaust Emission Factors for Marine Diesel Engines in China].

Water-borne transportation plays an important role in the economic and social development and contributes greatly to air pollution in China as well. An effective regulating policy is dependent on accurate estimation in terms of sorts, quantification and location of emissions. However, there is insufficient real and reliable data source for China's marine diesel engines and vessels. In order to employ fuel-based approach and ship activity-based approach to estimate accurately the exhaust emissions from water-borne transportation sector in China, emission factors of different types of marine diesel engines were investigated. Based on statistical analysis on Parent Engine emission test reports of 76 and 113 marine diesel engines manufactured by China's engine makers in accordance with IMO NOx TierⅠ and TierⅡ standards respectively as defined in MARPOL(International Convention for the Prevention of Pollution from Ships) Annex VI, abnormal data were statistically identified and eliminated by Grubbs' criterion method, fuel-based emission factors and energy-based emission factors of NOx, CO, HC and CO2 for 2-Stroke main engines, 4-Stroke main engines and 4-Stroke auxiliary engines were determined respectively. The results showed that fuel-based emission factors of NOx, CO, HC and CO2 for different types of marine diesel engines were 30.67-76.55, 3.01-6.13, 1.25-2.24 and 3141.15-3165.63 kg·t-1 respectively. Energy-based emission factors of NOx, CO, HC and CO2 for different types of marine diesel engines were 6.83-13.64, 0.61-1.35, 0.21-0.50 and 534.04-745.18 g·(kW·h)-1 respectively. In addition, the relationships of energy-based emission factors against engine load were expressed by power function or quadratic polynomial and the algorithm coefficients were determined. In addition, it is difficult to obtain the true emission levels of marine diesel engines in China through simple modification of emission factors reported by foreign institutes. In particular,considering the diversity of diesel engines onboard China's coastal and inland vessels, more samples and tests in terms of types and operational conditions are necessary to provide basic data for marine emission inventories in China. The results could provide applicable data for estimation of marine emissions in China.

Cattle encephalon glycoside and ignotin injection improves cognitive impairment in APPswe/PS1dE9 mice used as multitarget anti-Alzheimer's drug candidates.

BACKGROUND: Cattle encephalon glycoside and ignotin injection (CEGI), a multitargeted neurotrophic drug, has been widely used in the treatment of central and peripheral nerve injuries, such as stroke, hypoxic ischemic encephalopathy, and diabetic neuropathy in the People's Republic of China. However, data regarding the effect of CEGI on Alzheimer's disease (AD) remain scarce. The present study aimed to investigate the effect of CEGI on learning and memory in an APPswe/PS1dE9 double-transgenic mouse model, a suitable animal model of AD, and elucidate its possible mechanisms. MATERIALS AND METHODS: Five-month-old APP/PS1 mice were intraperitoneally administered 6.6 mL/kg or 13.2 mL/kg of CEGI for 1 month. After 1 month of administration, all mice received Morris water maze training and a probe test. Mouse brain sections were detected by standard biochemical and immunohistochemical measures. RESULTS: CEGI treatment significantly improved the spatial learning and memory deficits and decreased cerebral amyloid-ß42 levels in brain homogenates of APP/PS1 mice. CEGI treatment elevated the activities of superoxide dismutase, and reduced the levels of malondialdehyde. CEGI attenuated neuronal damage in the hippocampus of APP/PS1 mice and upregulated protein and gene expression of Bcl-2 and the ratio of Bcl-2/Bax. CEGI treatment decreased the number of Iba1(+) activated microglia in the cortex of the APP/PS1 mice. CONCLUSION: Our results showed that CEGI prevents memory impairment, possibly by decreasing the amyloid-ß42 levels in APP/PS1 mice and inhibiting oxidative stress, apoptosis, and inflammation, making CEGI a promising therapeutic agent for AD.

[Expression of tau-related protein in spinal cord of patients with Alzheimer's disease].

OBJECTIVE: To study the expression of tau-related protein in spinal cord of Chinese patients with Alzheimer's disease. METHODS: Gallays-Braak stain and immunohistochemical study for tau protein (AT8) were carried out in the spinal cord tissue (T2, T8, T10, L2 and S2 segments) of 3 Chinese patients with Alzheimer's disease. Seven age-matched cases without evidence of dementia or neurologic disease were used as controls. RESULTS: Neurofibrillary tangles were identified in the neurons of anterior horn in 2 Alzheimer's disease cases but none was observed in the controls. Tau-positive axons and astroglia were detected in all Alzheimer's disease cases. Tau immunoreactivity in spinal cord of the patients correlated with that in brain tissue. CONCLUSION: The expression of tau-related protein is demonstrated in the spinal cord of Alzheimer's disease patients suggesting that axonal transport defect may play a role in the pathogenesis of Alzheimer's disease.

[An experimental research of neuroglobin expression changes and neural apoptosis after traumatic brain injury].

OBJECTIVE: To study the expression changes of neuroglobin in rats with the model of diffuse traumatic brain injury and explore the relationship between the neuroglobin and neuron apoptosis in traumatic brain injury. METHODS: The diffuse traumatic brain injury of rats was induced by the Marmarou's 'weight-drop' device. And the immunohistochemical technique was used to detect the expression changes of neuroglobin and neuron apoptosis in rat brain at different time points post-injury. RESULTS: The expression of neuroglobin increased twice and reached peaks at 2 hours and 72 hours post-injury respectively. And the increased expression of neuroglobin from 30 minutes to 1 hour post-injury and from 48 hours to 72 hours post-injury accompanied with the decreased expression ratio of Bax to Bcl-2. CONCLUSION: The increased expression of neuroglobin in traumatic brain injury informed us that neuroglobin had anti-apoptosis action in post-injury neuron. It could protect the neuron from traumatic stress and secondary ischemia and hypoxia insults during ultra-early and acute stages.