Parkinson's disease (PD) is a neurodegenerative disorder with no absolute cure. The evidence of the involvement of gut microbiota in PD pathogenesis suggests the need to identify certain molecule(s) ...derived from the gut microbiota, which has the potential to manage PD. Osteocalcin (OCN), an osteoblast-secreted protein, has been shown to modulate brain function. Thus, it is of interest to investigate whether OCN could exert protective effect on PD and, if yes, whether the underlying mechanism lies in the subsequent changes in gut microbiota.
The intraperitoneal injection of OCN can effectively ameliorate the motor deficits and dopaminergic neuronal loss in a 6-hydroxydopamine-induced PD mouse model. The further antibiotics treatment and fecal microbiota transplantation experiments confirmed that the gut microbiota was required for OCN-induced protection in PD mice. OCN elevated Bacteroidetes and depleted Firmicutes phyla in the gut microbiota of PD mice with elevated potential of microbial propionate production and was confirmed by fecal propionate levels. Two months of orally administered propionate successfully rescued motor deficits and dopaminergic neuronal loss in PD mice. Furthermore, AR420626, the agonist of FFAR3, which is the receptor of propionate, mimicked the neuroprotective effects of propionate and the ablation of enteric neurons blocked the prevention of dopaminergic neuronal loss by propionate in PD mice.
Together, our results demonstrate that OCN ameliorates motor deficits and dopaminergic neuronal loss in PD mice, modulating gut microbiome and increasing propionate level might be an underlying mechanism responsible for the neuroprotective effects of OCN on PD, and the FFAR3, expressed in enteric nervous system, might be the main action site of propionate. Video abstract.
Perfluoroalkyl substances (PFAS) are widely used in various manufacturing processes. Accumulation of these chemicals has adverse effects on human health, including inflammation in multiple organs, ...yet how PFAS are sensed by host cells, and how tissue inflammation eventually incurs, is still unclear. Here, we show that the double-stranded DNA receptor AIM2 is able to recognize perfluorooctane sulfonate (PFOS), a common form of PFAS, to trigger IL-1β secretion and pyroptosis. Mechanistically, PFOS activates the AIM2 inflammasome in a process involving mitochondrial DNA release through the Ca
-PKC-NF-κB/JNK-BAX/BAK axis. Accordingly, Aim2
mice have reduced PFOS-induced inflammation, as well as tissue damage in the lungs, livers, and kidneys in both their basic condition and in an asthmatic exacerbation model. Our results thus suggest a function of AIM2 in PFOS-mediated tissue inflammation, and identify AIM2 as a major pattern recognition receptor in response to the environmental organic pollutants.
Although clinical studies have shown promise for targeting programmed cell death protein-1 (PD-1) and ligand (PD-L1) signaling in non-small cell lung cancer (NSCLC), the factors that predict which ...subtype patients will be responsive to checkpoint blockade are not fully understood.
We performed an integrated analysis on the multiple-dimensional data types including genomic, transcriptomic, proteomic, and clinical data from cohorts of lung adenocarcinoma public (discovery set) and internal (validation set) database and immunotherapeutic patients. Gene set enrichment analysis (GSEA) was used to determine potentially relevant gene expression signatures between specific subgroups.
We observed that
mutation significantly increased expression of immune checkpoints and activated T-effector and interferon-γ signature. More importantly, the
comutated subgroup manifested exclusive increased expression of PD-L1 and a highest proportion of
Meanwhile,
or
-mutated tumors showed prominently increased mutation burden and specifically enriched in the transversion-high (TH) cohort. Further analysis focused on the potential molecular mechanism revealed that
or
mutation altered a group of genes involved in cell-cycle regulating, DNA replication and damage repair. Finally, immunotherapeutic analysis from public clinical trial and prospective observation in our center were further confirmed that
or
mutation patients, especially those with co-occurring
mutations, showed remarkable clinical benefit to PD-1 inhibitors.
This work provides evidence that
and
mutation in lung adenocarcinoma may be served as a pair of potential predictive factors in guiding anti-PD-1/PD-L1 immunotherapy.
.
Copper and zinc are essential micronutrients, whose imbalance may be involved in the development and progression of cancer. However, the role of copper and/or zinc imbalance in the prognosis of ...hepatocellular carcinoma (HCC) is currently unclear. Our objective was to investigate the association between serum levels of copper, zinc and their ratio (copper/zinc) at diagnosis with HCC survival. We included 989 patients with incident HCC in this prospective cohort study, who were enrolled in the Guangdong Liver Cancer Cohort (GLCC) study within 30 days of diagnosis between September 2013 and February 2017. Serum copper and zinc were measured using inductively coupled plasma mass spectrometry. Primary outcomes were liver cancer‐specific survival (LCSS) and overall survival (OS). Cox proportional hazards models were used to calculate the multivariable hazard ratios (HRs) and 95% confidence interval (CI). Higher serum copper levels were strongly associated with worse LCSS (Q4 vs. Q1: HR = 1.87, 95% CI: 1.22–2.86; p < 0.01 for trend) and OS (Q4 vs. Q1: HR = 2.06, 95% CI: 1.36–3.11; p < 0.01 for trend). The calculated copper/zinc ratio was positively associated with LCSS (Q4 vs. Q1: HR = 1.31, 95% CI: 0.89–1.92; P = 0.04 for trend) and OS (Q4 vs. Q1: HR = 1.43, 95% CI: 0.99–2.08; P = 0.01 for trend). No overall associations were observed between serum zinc levels and LCSS or OS in the entire cohort. The results suggest that higher serum copper and copper in relation to zinc levels (i.e., higher copper/zinc ratio) may be associated with worse HCC survival, but serum zinc levels may be not associated with HCC survival.
What's new?
Copper and zinc are essential micronutrients whose imbalance may be involved in development and progression of cancer. Currently, the role of copper and/or zinc imbalance in the prognosis of hepatocellular carcinoma (HCC) however remains unclear. The authors examine for the first time whether serum levels of copper, zinc, and their ratios are associated with survival in a large prospective cohort of newly diagnosed patients. The findings suggest that higher copper levels and copper/zinc ratios are associated with worse survival, but serum zinc levels are not associated with HCC survival. The results may have important implications for the prognosis of HCC.
Esophageal squamous dysplasia is believed to be the precursor lesion of esophageal squamous cell carcinoma (ESCC); however, the genetic evolution from dysplasia to ESCC remains poorly understood. ...Here, we applied multi-region whole-exome sequencing to samples from two cohorts, 45 ESCC patients with matched dysplasia and carcinoma samples, and 13 tumor-free patients with only dysplasia samples. Our analysis reveals that dysplasia is heavily mutated and harbors most of the driver events reported in ESCC. Moreover, dysplasia is polyclonal, and remarkable heterogeneity is often observed between tumors and their neighboring dysplasia samples. Notably, copy number alterations are prevalent in dysplasia and persist during the ESCC progression, which is distinct from the development of esophageal adenocarcinoma. The sharp contrast in the prevalence of the 'two-hit' event on TP53 between the two cohorts suggests that the complete inactivation of TP53 is essential in promoting the development of ESCC.The pathogenesis of oesophageal squamous cell carcinoma is a multi-step process but the genetic determinants behind this progression are unknown. Here the authors use multi-region exome sequencing to comprehensively investigate the genetic evolution of precursor dysplastic lesions and untransformed oesophagus.
Novel diagnostic and prognostic biomarkers of cancers are needed to improve precision medicine. Circular RNAs act as important regulators in cancers at the transcriptional and posttranscriptional ...levels. The circular RNA circMAN1A2 is highly expressed in nasopharyngeal carcinoma according to our previous RNA sequencing data; however, the expression and functions of circMAN1A2 in cancers are still obscure. Therefore, in this study, we evaluated the expression of circMAN1A2 in the sera of patients with nasopharyngeal carcinoma and other malignant tumors and analyzed its correlations with clinical features and diagnostic values. The expression levels of circMAN1A2 were detected by quantitative real‐time PCR, and the correlations of clinical features with circMAN1A2 expression were analyzed by χ2 tests. Receiver operating characteristic curves were used to evaluate the clinical applications of circMAN1A2. The results showed that circMAN1A2 was upregulated in nasopharyngeal carcinoma, oral cancer, thyroid cancer, ovarian cancer, and lung cancer, with areas under the curves of 0.911, 0.779, 0.734, 0.694, and 0.645, respectively, indicating the good diagnostic value of circMAN1A2. Overall, our findings suggested that circMAN1A2 could be a serum biomarker for malignant tumors, providing important insights into diagnostic approaches for malignant tumors. Further studies are needed to elucidate the mechanisms of circMAN1A2 in the pathogenesis of cancer.
We verified that circMAN1A2 was significantly upregulated in the sera of patients with NPC, oral cancer, thyroid cancer, ovarian cancer, and lung cancer and had good clinical diagnostic value. We speculate that circMAN1A2 could be a serum biomarker for malignant cancers and provide effective clues for the early diagnosis of malignant cancers.
Emerging evidence suggests that epithelial‐mesenchymal transitions (EMTs) play important roles in tumor metastasis and recurrence. Understanding molecular mechanisms that regulate the EMT process is ...crucial for improving treatment of hepatocellular carcinoma (HCC). MicroRNAs (miRNAs) play important roles in HCC; however, the mechanisms by which miRNAs target the EMT and their therapeutic potential remains largely unknown. To better explore the roles of miRNAs in the EMT process, we established an EMT model in HCC cells by transforming growth factor beta 1 treatment and found that several tumor‐related miRNAs were significantly decreased. Among these miRNAs, miR‐125b expression was most strongly suppressed. We also found down‐regulation of miR‐125b in most HCC cells and clinical specimens, which correlated with cellular differentiation in HCC patients. We then demonstrated that miR‐125b overexpression attenuated EMT phenotype in HCC cancer cells, whereas knockdown of miR‐125b promoted the EMT phenotype in vitro and in vivo. Moreover, we found that miR‐125b attenuated EMT‐associated traits, including chemoresistance, migration, and stemness in HCC cells, and negatively correlated with EMT and cancer stem cell (CSC) marker expressions in HCC specimens. miR‐125b overexpression could inhibit CSC generation and decrease tumor incidence in the mouse xenograft model. Mechanistically, our data revealed that miR‐125b suppressed EMT and EMT‐associated traits of HCC cells by targeting small mothers against decapentaplegic (SMAD)2 and 4. Most important, the therapeutic delivery of synthetic miR‐125b mimics decreased the target molecule of CSC and inhibited metastasis in the mice model. These findings suggest a potential therapeutic treatment of miR‐125b for liver cancer. Conclusion: miR‐125b exerts inhibitory effects on EMT and EMT‐associated traits in HCC by SMAD2 and 4. Ectopic expression of miR‐125b provides a promising strategy to treat HCC. (Hepatology 2015;62:801–815)
Metal–organic frameworks (MOFs) have recently emerged as a type of uniformly and periodically atom‐distributed precursor and efficient self‐sacrificial template to fabricate hierarchical ...porous‐carbon‐related nanostructured functional materials. For the first time, a Cu‐based MOF, i.e., Cu‐NPMOF is used, whose linkers contain nitrogen and phosphorus heteroatoms, as a single precursor and template to prepare novel Cu3P nanoparticles (NPs) coated by a N,P‐codoped carbon shell that is extended to a hierarchical porous carbon matrix with identical uniform N and P doping (termed Cu3P@NPPC) as an electrocatalyst. Cu3P@NPPC demonstrates outstanding activity for both the hydrogen evolution and oxygen reduction reaction, representing the first example of a Cu3P‐based bifunctional catalyst for energy‐conversion reactions. The high performances are ascribed to the high specific surface area, the synergistic effects of the Cu3P NPs with intrinsic activity, the protection of the carbon shell, and the hierarchical porous carbon matrix doped by multiheteroatoms. This strategy of using a diverse MOF as a structural and compositional material to create a new multifunctional composite/hybrid may expand the opportunities to explore highly efficient and robust non‐noble‐metal catalysts for energy‐conversion reactions.
Cu3P nanoparticles coated by a N,P‐codoped carbon shell (hierarchical porous carbon matrix) are prepared using a novel Cu‐based metal–organic framework (MOF) containing dual linkers as a template and single precursor. The Cu3P@NPPC catalyst demonstrates a high specific surface area and affords remarkable bifunctional electrocatalytic performance for hydrogen evolution reaction and oxygen reduction reaction with long‐term durability for both reactions.
Ischemic stroke leads to neuronal damage induced by excitotoxicity, inflammation, and oxidative stress. Astrocytes play diverse roles in stroke and ischemia‐induced inflammation, and autophagy is ...critical for maintaining astrocytic functions. Our previous studies showed that the activation of G protein‐coupled receptor 30 (GPR30), an estrogen membrane receptor, protected neurons from excitotoxicity. However, the role of astrocytic GPR30 in maintaining autophagy and neuroprotection remained unclear. In this study, we found that the neuroprotection induced by G1 (GPR30 agonist) in wild‐type mice after a middle cerebral artery occlusion was completely blocked in GPR30 conventional knockout (KO) mice but partially attenuated in astrocytic or neuronal GPR30 KO mice. In cultured primary astrocytes, glutamate exposure induced astrocyte proliferation and decreased astrocyte autophagy by activating mammalian target of rapamycin (mTOR) and c‐Jun N‐terminal kinase (JNK) and inhibiting p38 mitogen‐activated protein kinase (MAPK) pathway. G1 treatment restored autophagy to its basal level by regulating the p38 pathway but not the mTOR and JNK signaling pathways. Our findings revealed a key role of GPR30 in neuroprotection via the regulation of astrocyte autophagy and support astrocytic GPR30 as a potential drug target against ischemic brain damage.
Main Points
Astrocytic GPR30 was involved in the neuroprotection.
Autophagic deficiency of astrocytes induced by glutamate promoted inflammatory cytokine release.
GPR30 activation restored autophagy balance in astrocytes by regulating the p38 MAPK pathway.
SARS-CoV-2 infection has become an urgent public health concern worldwide, severely affecting our society and economy due to the long incubation time and high prevalence. People spare no effort on ...the rapid development of vaccine and treatment all over the world. Amongst the numerous ways of tackling this pandemic, some approaches using extracellular vesicles (EVs) are emerging. In this review, we summarize current prevalence and pathogenesis of COVID-19, involving the combination of SARS-CoV-2 and virus receptor ACE2, endothelial dysfunction and micro thrombosis, together with cytokine storm. We also discuss the ongoing EVs-based strategies for the treatment of COVID-19, including mesenchymal stem cell (MSC)-EVs, drug-EVs, vaccine-EVs, platelet-EVs, and others. This manuscript provides the foundation for the development of targeted drugs and vaccines for SARS-CoV-2 infections.