The role of silver nanoparticles alone and combined with imipenem on carbapenem-resistant Klebsiella pneumoniae.

AIMS: Carbapenem-resistant Klebsiella pneumoniae (CRKP) infections poses a significant threat to human health, necessitating urgent development of new antimicrobial agents. Silver nanoparticles (AgNPs), which are among the most widely used engineered nanomaterials, have been extensively studied. However, the impact of AgNPs on CRKP and the potential for drug resistance development remain inadequately explored. METHODS AND RESULTS: In this study, broth dilution method was used to determine the minimum inhibitory concentration (MIC) was determined using the broth dilution method. Results indicated MIC values of 93.1 ± 193.3 µg ml-1 for AgNPs, 2.3 ± 5.1 µg ml-1 for AgNO3, and 25.1 ± 48.3 µg ml-1 for imipenem (IMI). The combined inhibitory effect of AgNPs and IMI on CRKP was assessed using the checkerboard method. Moreover, after 6-20 generations of continuous culture, the MIC value of AgNPs increased 2-fold. Compared to IMI, resistance of Kl. pneumoniae to AgNPs developed more slowly, with a higher fold increase in MIC observed after 20 generations. Whole-genome sequencing revealed four nonsynonymous single nucleotide polymorphism mutations in CRKP after 20 generations of AgNP treatment. CONCLUSION: We have demonstrated that AgNPs significantly inhibit CRKP isolates and enhance the antibacterial activity of imipenem against Kl. pneumoniae. Although the development of AgNP resistance is gradual, continued efforts are necessary for monitoring and studying the mechanisms of AgNP resistance.

Caffeic acid alleviates cerebral ischemic injury in rats by resisting ferroptosis via Nrf2 signaling pathway.

There are few effective and safe neuroprotective agents for the treatment of ischemic stroke currently. Caffeic acid is a phenolic acid that widely exists in a number of plant species. Previous studies show that caffeic acid ameliorates brain injury in rats after cerebral ischemia/reperfusion. In this study we explored the protective mechanisms of caffeic acid against oxidative stress and ferroptosis in permanent cerebral ischemia. Ischemia stroke was induced on rats by permanent middle cerebral artery occlusion (pMCAO). Caffeic acid (0.4, 2, 10 mg·kg-1·d-1, i.g.) was administered to the rats for 3 consecutive days before or after the surgery. We showed that either pre-pMCAO or post-pMCAO administration of caffeic acid (2 mg·kg-1·d-1) effectively reduced the infarct volume and improved neurological outcome. The therapeutic time window could last to 2 h after pMCAO. We found that caffeic acid administration significantly reduced oxidative damage as well as neuroinflammation, and enhanced antioxidant capacity in pMCAO rat brain. We further demonstrated that caffeic acid down-regulated TFR1 and ACSL4, and up-regulated glutathione production through Nrf2 signaling pathway to resist ferroptosis in pMCAO rat brain and in oxygen glucose deprivation/reoxygenation (OGD/R)-treated SK-N-SH cells in vitro. Application of ML385, an Nrf2 inhibitor, blocked the neuroprotective effects of caffeic acid in both in vivo and in vitro models, evidenced by excessive accumulation of iron ions and inactivation of the ferroptosis defense system. In conclusion, caffeic acid inhibits oxidative stress-mediated neuronal death in pMCAO rat brain by regulating ferroptosis via Nrf2 signaling pathway. Caffeic acid might serve as a potential treatment to relieve brain injury after cerebral ischemia. Caffeic acid significantly attenuated cerebral ischemic injury and resisted ferroptosis both in vivo and in vitro. The regulation of Nrf2 by caffeic acid initiated the transcription of downstream target genes, which were shown to be anti-inflammatory, antioxidative and antiferroptotic. The effects of caffeic acid on neuroinflammation and ferroptosis in cerebral ischemia were explored in a primary microglia-neuron coculture system. Caffeic acid played a role in reducing neuroinflammation and resisting ferroptosis through the Nrf2 signaling pathway, which further suggested that caffeic acid might be a potential therapeutic method for alleviating brain injury after cerebral ischemia.

PHPB ameliorates memory deficits and reduces oxidative injury in Alzheimer's disease mouse model by activating Nrf2 signaling pathway.

Alzheimer's disease (AD), a progressive neurodegenerative disorder, is the most common cause of dementia in elderly people and substantially affects patient quality of life. Oxidative stress is considered a key factor in the development of AD. Nrf2 plays a vital role in maintaining redox homeostasis and regulating neuroinflammatory responses in AD. Previous studies show that potassium 2-(1-hydroxypentyl)-benzoate (PHPB) exerts neuroprotective effects against cognitive impairment in a variety of dementia animal models such as APP/PS1 transgenic mice. In this study we investigated whether PHPB ameriorated the progression of AD by reducing oxidative stress (OS) damage. Both 5- and 13-month-old APP/PS1 mice were administered PHPB (100 mg·kg-1·d-1, i.g.) for 10 weeks. After the cognition assessment, the mice were euthanized, and the left hemisphere of the brain was harvested for analyses. We showed that 5-month-old APP/PS1 mice already exhibited impaired performance in the step-down test, and knockdown of Nrf2 gene only slightly increased the impairment, while knockdown of Nrf2 gene in 13-month-old APP/PS1 mice resulted in greatly worse performance. PHPB administration significantly ameliorated the cognition impairments and enhanced antioxidative capacity in APP/PS1 mice. In addition, PHPB administration significantly increased the p-AKT/AKT and p-GSK3ß/GSK3ß ratios and the expression levels of Nrf2, HO-1 and NQO-1 in APP/PS1 mice, but these changes were abolished by knockdown of Nrf2 gene. In SK-N-SH APPwt cells and primary mouse neurons, PHPB (10 µM) significantly increased the p-AKT/AKT and p-GSK3ß/GSK3ß ratios and the level of Nrf2, which were blocked by knockdown of Nrf2 gene. In summary, this study demonstrates that PHPB exerts a protective effect via the Akt/GSK3ß/Nrf2 pathway and it might be a promising neuroprotective agent for the treatment of AD.

Mitophagy protects against silver nanoparticle-induced hepatotoxicity by inhibiting mitochondrial ROS and the NLRP3 inflammasome.

Silver nanoparticles (AgNPs) have wide clinical applications because of their excellent antibacterial properties; however, they can cause liver inflammation in animals. Macrophages are among the main cells mediating inflammation and are also responsible for the phagocytosis of nanomaterials. The NLRP3 inflammasome is a major mechanism of inflammation, and its activation both induces cytokine release and triggers inflammatory cell death (i.e., pyroptosis). In previous studies, we demonstrated that mitophagy activation plays a protective role against AgNP-induced hepatotoxicity. However, the exact molecular mechanisms underlying these processes are not fully understood. In this study, we demonstrate that AgNP exposure induces NLRP3 inflammasome activation, mitochondrial damage and pyroptosis in vivo and in vitro. NLRP3 silencing or inhibiting mitochondrial reactive oxygen species (ROS) overproduction reduces PINK1-Parkin-mediated mitophagy. Meanwhile, the inhibition of mitophagy ROS production, mitochondrial, NLRP3-mediated inflammation, and pyroptosis in RAW264.7 cells were more pronounced than in the control group. These results suggest that PINK1-Parkin-mediated mitophagy plays a protective role by reducing AgNP-induced mitochondrial ROS and subsequent NLRP3 inflammasome activation.

Genotoxicity Assessment of Haloacetaldehyde Disinfection Byproducts via a Simplified Yeast-Based Toxicogenomics Assay.

Haloacetaldehydes (HALs) represent the third-largest category of disinfection byproducts (DBPs) in drinking water in terms of weight. As a subset of unregulated DBPs, only a few HALs have undergone assessment, yielding limited information regarding their genotoxicity mechanisms. Herein, we developed a simplified yeast-based toxicogenomics assay to evaluate the genotoxicity of five specific HALs. This assay recorded the protein expression profiles of eight Saccharomyces cerevisiae strains fused with green fluorescent protein, including all known DNA damage and repair pathways. High-resolution real-time pathway activation data and protein expression profiles in conjunction with clustering analysis revealed that the five HALs induced various DNA damage and repair pathways. Among these, chloroacetaldehyde and trichloroacetaldehyde were found to be positively associated with genotoxicity, while dichloroacetaldehyde, bromoacetaldehyde, and tribromoacetaldehyde displayed negative associations. The protein effect level index, which are molecular end points derived from a toxicogenomics assay, exhibited a statistically significant positive correlation with the results of traditional genotoxicity assays, such as the comet assay (rp = 0.830 and p < 0.001) and SOS/umu assay (rp = 0.786 and p = 0.004). This yeast-based toxicogenomics assay, which employs a minimal set of gene biomarkers, can be used for mechanistic genotoxicity screening and assessment of HALs and other chemical compounds. These results contribute to bridging the knowledge gap regarding the molecular mechanisms underlying the genotoxicity of HALs and enable the categorization of HALs based on their distinct DNA damage and repair mechanisms.

A comparison study between dimethyl itaconate and dimethyl fumarate in electrophilicity, Nrf2 activation, and anti-inflammation in vitro.

Dimethyl itaconate (DMI) is an analog of dimethyl fumarate (DMF), an approved NF-E2-related Factor 2 (Nrf2) activator for multiple sclerosis. This study evaluated the potential of DMI as an anti-inflammatory agent by comparing DMI with DMF in electrophilicity, Nrf2 activation, and anti-inflammation in vitro. The results showed that DMI was less electrophilic but better at inducing a durable activation of Nrf2 when compared with DMF. However, DMI demonstrated poor anti-inflammatory effects in Jurkat cells, bone marrow-derived dendritic cells, and RAW264.7 cells. Our study suggested that DMI was a potent electrophilic Nrf2 activator but was probably not a promising anti-inflammatory agent.

ALS-causing SOD1 mutants regulate occludin phosphorylation/ubiquitination and endocytic trafficking via the ITCH/Eps15/Rab5 axis.

It is increasingly recognized that blood-spinal cord barrier (BSCB) breakdown is a hallmark of amyotrophic lateral sclerosis (ALS). BSCB integrity is disrupted prior to disease onset. Occludin, as the functional component of the endothelial barrier, is downregulated in mouse models expressing ALS-linked superoxide dismutase-1 (SOD1) mutants. However, the molecular mechanisms underlying the regulation of occludin expression remain elusive. Here, using SOD1G93A transgenic mice and endothelial cells expressing SOD1 mutants of different biochemical characteristics, we found that the SOD1 mutation disrupted endothelial barrier integrity and that the occludin expression level was downregulated with disease progression. Our mechanistic studies revealed that abnormal reactive oxygen species (ROS) in mutant SOD1-expressing cells induced occludin phosphorylation, which facilitated the subsequent occludin ubiquitination mediated by the E3 ligase ITCH. Moreover, ubiquitinated occludin interacted with Eps15 to initiate its internalization, then trafficked to Rab5-positive vesicles and be degraded by proteasomes, resulting in a reduction in cell surface localization and total abundance. Notably, either ITCH or Eps15 knockdown was sufficient to rescue occludin degradation and ameliorate endothelial barrier disruption. In conclusion, our study reveals a novel mechanism of occludin degradation mediated by ALS-causing SOD1 mutants and demonstrates a role for occludin in regulating BSCB integrity.

Molecular mechanisms of mitophagy and its roles in neurodegenerative diseases.

Neurodegenerative diseases are the most common diseases of the nervous system in elderly people, which are currently incurable and cause great burden to families and societies. Mitochondria are the energy factory of the cell and have extremely important effects on neuronal function. The elimination of dysfunctional mitochondria is essential for the mitochondrial metabolic homeostasis, energy supply, and neuronal survival. Recent studies suggest that the impaired mitophagy may lead to the accumulation of damaged mitochondria and therefore contribute to the progression of neurodegenerative diseases. This review mainly focuses on mitophagy, mitochondrial dynamics, and their abnormal changes in neurodegenerative diseases, as well as the therapeutic strategies targeting mitophagy that have shown promise in recent preclinical and clinical studies.

Dependence of Graphene Oxide (GO) Toxicity on Oxidation Level, Elemental Composition, and Size.

The mass production of graphene oxide (GO) unavoidably elevates the chance of human exposure, as well as the possibility of release into the environment with high stability, raising public concern as to its potential toxicological risks and the implications for humans and ecosystems. Therefore, a thorough assessment of GO toxicity, including its potential reliance on key physicochemical factors, which is lacking in the literature, is of high significance and importance. In this study, GO toxicity, and its dependence on oxidation level, elemental composition, and size, were comprehensively assessed. A newly established quantitative toxicogenomic-based toxicity testing approach, combined with conventional phenotypic bioassays, were employed. The toxicogenomic assay utilized a GFP-fused yeast reporter library covering key cellular toxicity pathways. The results reveal that, indeed, the elemental composition and size do exert impacts on GO toxicity, while the oxidation level exhibits no significant effects. The UV-treated GO, with significantly higher carbon-carbon groups and carboxyl groups, showed a higher toxicity level, especially in the protein and chemical stress categories. With the decrease in size, the toxicity level of the sonicated GOs tended to increase. It is proposed that the covering and subsequent internalization of GO sheets might be the main mode of action in yeast cells.

Genotoxicity Assessment of Drinking Water Disinfection Byproducts by DNA Damage and Repair Pathway Profiling Analysis.

Genotoxicity is considered a major concern for drinking water disinfection byproducts (DBPs). Of over 700 DBPs identified to date, only a small number has been assessed with limited information for DBP genotoxicity mechanism(s). In this study, we evaluated genotoxicity of 20 regulated and unregulated DBPs applying a quantitative toxicogenomics approach. We used GFP-fused yeast strains that examine protein expression profiling of 38 proteins indicative of all known DNA damage and repair pathways. The toxicogenomics assay detected genotoxicity potential of these DBPs that is consistent with conventional genotoxicity assays end points. Furthermore, the high-resolution, real-time pathway activation and protein expression profiling, in combination with clustering analysis, revealed molecular level details in the genotoxicity mechanisms among different DBPs and enabled classification of DBPs based on their distinct DNA damage effects and repair mechanisms. Oxidative DNA damage and base alkylation were confirmed to be the main molecular mechanisms of DBP genotoxicity. Initial exploration of QSAR modeling using moleular genotoxicity end points (PELI) suggested that genotoxicity of DBPs in this study was correlated with topological and quantum chemical descriptors. This study presents a toxicogenomics-based assay for fast and efficient mechanistic genotoxicity screening and assessment of a large number of DBPs. The results help to fill in the knowledge gap in the understanding of the molecular mechanisms of DBP genotoxicity.

A Quantitative Toxicogenomics Assay for High-throughput and Mechanistic Genotoxicity Assessment and Screening of Environmental Pollutants.

The ecological and health concern of mutagenicity and carcinogenicity potentially associated with an overwhelmingly large and ever-increasing number of chemicals demands for cost-effective and feasible method for genotoxicity screening and risk assessment. This study proposed a genotoxicity assay using GFP-tagged yeast reporter strains, covering 38 selected protein biomarkers indicative of all the seven known DNA damage repair pathways. The assay was applied to assess four model genotoxic chemicals, eight environmental pollutants and four negative controls across six concentrations. Quantitative molecular genotoxicity end points were derived based on dose response modeling of a newly developed integrated molecular effect quantifier, Protein Effect Level Index (PELI). The molecular genotoxicity end points were consistent with multiple conventional in vitro genotoxicity assays, as well as with in vivo carcinogenicity assay results. Further more, the proposed genotoxicity end point PELI values quantitatively correlated with both comet assay in human cell and carcinogenicity potency assay in mice, providing promising evidence for linking the molecular disturbance measurements to adverse outcomes at a biological relevant level. In addition, the high-resolution DNA damaging repair pathway alternated protein expression profiles allowed for chemical clustering and classification. This toxicogenomics-based assay presents a promising alternative for fast, efficient and mechanistic genotoxicity screening and assessment of drugs, foods, and environmental contaminants.

Toxicity Assessment of 4-Methyl-1-cyclohexanemethanol and Its Metabolites in Response to a Recent Chemical Spill in West Virginia, USA.

The large-scale chemical spill on January 9, 2014 from coal processing and cleaning storage tanks of Freedom Industries in Charleston affected the drinking water supply to 300,000 people in Charleston, West Virginia metropolitan, while the short-term and long-term health impacts remain largely unknown and need to be assessed and monitored. There is a lack of publically available toxicological information for the main contaminant 4-methyl-1-cyclohexanemethanol (4-MCHM). Particularly, little is known about 4-MCHM metabolites and their toxicity. This study reports timely and original results of the mechanistic toxicity assessment of 4-MCHM and its metabolites via a newly developed quantitative toxicogenomics approach, employing proteomics analysis in yeast cells and transcriptional analysis in human cells. These results suggested that, although 4-MCHM is considered only moderately toxic based on the previous limited acute toxicity evaluation, 4-MCHM metabolites were likely more toxic than 4-MCHM in both yeast and human cells, with different toxicity profiles and potential mechanisms. In the yeast library, 4-MCHM mainly induced chemical stress related to transmembrane transport and transporter activity, while 4-MCHM metabolites of S9 mainly induced oxidative stress related to antioxidant activity and oxidoreductase activity. With human A549 cells, 4-MCHM mainly induced DNA damage-related biomarkers, which indicates that 4-MCHM is related to genotoxicity due to its DNA damage effect on human cells and therefore warrants further chronic carcinogenesis evaluation.

Toxicity mechanisms identification via gene set enrichment analysis of time-series toxicogenomics data: impact of time and concentration.

The advance in high-throughput "toxicogenomics" technologies, which allows for concurrent monitoring of cellular responses globally upon exposure to chemical toxicants, presents promises for next-generation toxicity assessment. It is recognized that cellular responses to toxicants have a highly dynamic nature, and exhibit both temporal complexity and dose-response shifts. Most current gene enrichment or pathway analysis lack the recognition of the inherent correlation within time series data, and may potentially miss important pathways or yield biased and inconsistent results that ignore dynamic patterns and time-sensitivity. In this study, we investigated the application of two score metrics for GSEA (gene set enrichment analysis) to rank the genes that consider the temporal gene expression profile. One applies a novel time series CPCA (common principal components analysis) to generate scores for genes based on their contributions to the common temporal variation among treatments for a given chemical at different concentrations. Another one employs an integrated altered gene expression quantifier-TELI (transcriptional effect level index) that integrates altered gene expression magnitude over the exposure time. By comparing the GSEA results using two different ranking metrics for examining the dynamic responses of reporter cells treated with various dose levels of three model toxicants, mitomycin C, hydrogen peroxide, and lead nitrate, the analysis identified and revealed different toxicity mechanisms of these chemicals that exhibit chemical-specific, as well as time-aware and dose-sensitive nature. The ability, advantages, and disadvantages of varying ranking metrics were discussed. These findings support the notion that toxicity bioassays should account for the cells' complex dynamic responses, thereby implying that both data acquisition and data analysis should look beyond simple traditional end point responses.

[Recent advances in pharmacological intervention for prediabetes].

Prediabetes is an abnormal condition between normal glucose metabolism and diabetes mellitus. Impaired glucose tolerance (IGT) is an indicator of high-risk state of prediabetes. Positive interventions of IGT, including life style changes and pharmacological intervention, can effectively postpone and reduce the development of prediabetes into type 2 diabetes mellitus, suggesting that IGT is a key point of diabetes prevention. Currently, pharmacological intervention for prediabetes is still at early stage. In this review, we summarizes recent clinical and preclinical studies on pharmacological intervention for prediabetes, and studies in the development of animal models with IGT and the application of new techniques. We also discuss the prospects of drugs for diabetes prevention, especially with the traditional Chinese medicine.

Comparative and mechanistic genotoxicity assessment of nanomaterials via a quantitative toxicogenomics approach across multiple species.

This study reports a comparative and mechanistic genotoxicity assessment of four engineered nanomaterials (ENMs) across three species, including E. coli, yeast, and human cells, with the aim to reveal the distinct potential genotoxicity mechanisms among the different nanomaterials and their association with physiochemical features. Both the conventional phenotypic alkaline comet test and the newly developed quantitative toxicogenomics assay, that detects and quantifies molecular level changes in the regulation of six DNA damage repair pathways, were employed. The proposed molecular endpoints derived from the toxicogenomics assays, namely TELI (Transcriptional Effect Level Index) and PELI (Protein Effect Level Index), correlated well with the phenotypic DNA damage endpoints from comet tests, suggesting that the molecular genotoxicity assay is suitable for genotoxicity detection. Temporal altered gene or protein expression profiles revealed various potential DNA damage types and relevant genotoxic mechanisms induced by the tested ENMs. nTiO2_a induced a wide spectrum of DNA damage consistently across three species. Three carbon-based ENMs, namely carbon black, single wall carbon nanotube (SWCNT) and fullerene, exhibited distinct, species and ENM property-dependent DNA damage mechanisms. All carbon based ENMs induced relatively weak DNA damage repair response in E. coli, but more severe DNA double strand break in eukaryotes. The differences in cellular structure and defense systems among prokaryotic and eukaryotic species lead to distinct susceptibility and mechanisms for ENM uptake and, thus, varying DNA damages and repair responses. The observation suggested that eukaryotes, especially mammalian cells, are likely more susceptible to genotoxicity than prokaryotes in the ecosystem when exposed to these ENMs.

A quantitative toxicogenomics assay reveals the evolution and nature of toxicity during the transformation of environmental pollutants.

The incomplete mineralization of contaminants of emerging concern (CECs) during the advanced oxidation processes can generate transformation products that exhibit toxicity comparable to or greater than that of the original contaminant. In this study, we demonstrated the application of a novel, fast, and cost-effective quantitative toxicogenomics-based approach for the evaluation of the evolution and nature of toxicity along the electro-Fenton oxidative degradation of three representative CECs whose oxidative degradation pathways have been relatively well studied, bisphenol A, triclosan, and ibuprofen. The evolution of toxicity as a result of the transformation of parent chemicals and production of intermediates during the course of degradation are monitored, and the quantitative toxicogenomics assay results revealed the dynamic toxicity changes and mechanisms, as well as their association with identified intermediates during the electro-Fenton oxidation process of the selected CECs. Although for the three CECs, a majority (>75%) of the parent compounds disappeared at the 15 min reaction time, the nearly complete elimination of toxicity required a minimal 30 min reaction time, and they seem to correspond to the disappearance of identified aromatic intermediates. Bisphenol A led to a wide range of stress responses, and some identified transformation products containing phenolic or quinone group, such as 1,4-benzoquinone and hydroquinone, likely contributed to the transit toxicity exhibited as DNA stress (genotoxicity) and membrane stress during the degradation. Triclosan is known to cause severe oxidative stress, and although the oxidative damage potential decreased concomitantly with the disappearance of triclosan after a 15 min reaction, the sustained toxicity associated with both membrane and protein stress was likely attributed at least partially to the production of 2,4-dichlorophenol that is known to cause the production of abnormal proteins and affect the cell membrane. Ibuprofen affects the cell transporter function and exhibited significantly high membrane stress related to both membrane structure and function. Oxidative degradation of ibuprofen led to a shift in its toxicity profile from mainly membrane stress to one that exhibited not only sustained membrane stress but also protein stress and DNA stress. The information-rich and high-resolution toxicogenomics results served as "fingerprints" that discerned and revealed the toxicity mechanism at the molecular level among the CECs and their oxidation transformation products. This study demonstrated that the quantitative toxicogenomics assay can serve as a useful tool for remediation technology efficacy assessment and provide guidance about process design and optimization for desired toxicity elimination and risk reduction.

Predictive value of pre-operative prognostic nutritional index and systemic immune-inflammation index for efficacy and survival in patients with non-small cell lung cancer undergoing neoadjuvant chemotherapy.

OBJECTIVE: To explore the predictive value of preoperative prognostic nutritional index (PNI) and systemic immune inflammation index (SII) in relation to the efficacy and prognosis in patients with non-small cell lung cancer (NSCLC) undergoing neoadjuvant chemotherapy (NACT). METHODS: Data of patients with stage IIIA-N2 NSCLC who received NACT in the 910th Hospital of Chinese People's Liberation Army from January 2017 to April 2020 were retrospectively analysed. Patients undergoing NACT were divided into the pCR group (80 cases with complete remission or partial remission) and the non-pCR group (46 cases with stable disease or progressive disease) in accordance with their treatment outcome. The pathologic and clinical data of the patients were collected and analysed to identify the factors affecting efficacy of NACT for stage IIIa-N2 NSCLC, and to evaluate the predictive value of PNI and SII in determining the efficacy of NACT. The patients were followed up for 3 years to observe the overall survival, and Cox regression analysis was employed to identify the risk factors affecting patient survival. Furthermore, the effect of PNI and SII on the survival time was analysed. RESULTS: Multivariate regression analysis showed that tumor diameter, PNI, and SII were influencing factors for poor efficacy of NACT in patients with stage IIIa-N2 NSCLC. The non-pCR group exhibited a higher mortality within 3 years, thus a lower 3-year overall survival rate than the pCR group (P<0.05). Cox regression analysis revealed that both PNI and SII were risk factors for poor prognosis in patients with stage IIIa-N2 NSCLC undergoing NACT. Further analysis found a lower 3-year survival rate in patients with low PNI and high SII than in counterparts (P<0.05). CONCLUSION: Tumor diameter, PNI and SII are risk factors for poor efficacy in patients with stage IIIa-N2 NSCLC undergoing NACT. Low PNI and high SII can indicate a poor prognosis in these patients.

Evaluation of cytotoxic, genotoxic and inflammatory responses of nanoparticles from photocopiers in three human cell lines.

BACKGROUND: Photocopiers emit nanoparticles with complex chemical composition. Short-term exposures to modest nanoparticle concentrations triggered upper airway inflammation and oxidative stress in healthy human volunteers in a recent study. To further understand the toxicological properties of copier-emitted nanoparticles, we studied in-vitro their ability to induce cytotoxicity, pro-inflammatory cytokine release, DNA damage, and apoptosis in relevant human cell lines. METHODS: Three cell types were used: THP-1, primary human nasal- and small airway epithelial cells. Following collection in a large volume photocopy center, nanoparticles were extracted, dispersed and characterized in the cell culture medium. Cells were doped at 30, 100 and 300 µg/mL administered doses for up to 24 hrs. Estimated dose delivered to cells, was ~10% and 22% of the administered dose at 6 and 24 hrs, respectively. Gene expression analysis of key biomarkers was performed using real time quantitative PCR (RT-qPCR) in THP-1 cells at 5 µg nanoparticles/mL for 6-hr exposure for confirmation purposes. RESULTS: Multiple cytokines, GM-CSF, IL-1ß, IL-6, IL-8, IFNγ, MCP-1, TNF-α and VEGF, were significantly elevated in THP-1 cells in a dose-dependent manner. Gene expression analysis confirmed up-regulation of the TNF-α gene in THP-1 cells, consistent with cytokine findings. In both primary epithelial cells, cytokines IL-8, VEGF, EGF, IL-1α, TNF-α, IL-6 and GM-CSF were significantly elevated. Apoptosis was induced in all cell lines in a dose-dependent manner, consistent with the significant up-regulation of key apoptosis-regulating genes P53 and Casp8 in THP-1 cells. No significant DNA damage was found at any concentration with the comet assay. Up-regulation of key DNA damage and repair genes, Ku70 and Rad51, were also observed in THP-1 cells, albeit not statistically significant. Significant up-regulation of the key gene HO1 for oxidative stress, implicates oxidative stress induced by nanoparticles. CONCLUSIONS: Copier-emitted nanoparticles induced the release of pro-inflammatory cytokines, apoptosis and modest cytotoxicity but no DNA damage in all three-human cell lines. Taken together with gene expression data in THP-1 cells, we conclude that these nanoparticles are directly responsible for inflammation observed in human volunteers. Further toxicological evaluations of these nanoparticles, including across different toner formulations, are warranted.

Protective effect of human umbilical cord mesenchymal stem cell derived conditioned medium in a mutant TDP-43 induced motoneuron-like cellular model of ALS.

Amyotrophic lateral sclerosis (ALS) is a multi-factor neurodegenerative disease, characterized by the loss of motor neurons. TAR DNA-binding protein 43 (TDP-43) mutation, accumulation and aggregation, as well as oxidative stress are recognized as major pathological denominators and biochemical markers for ALS. Recently, human umbilical cord mesenchymal stem cell-derived conditioned medium (UC-CM) has been introduced to treat ALS patients. However, there is no research for the protective effect of UC-CM on the TDP-43 model of ALS. In this study, we evaluated the potential neuroprotective effect of UC-CM on a cellular ALS model expressing TDP-43mutant M337V, as well as its underlying mechanism. We found that 24 h UC-CM treatment could protect M337V expressing motor neurons by increasing cell viability and reducing LDH leakage. Furthermore, the aggregation of M337V, generation of ROS, malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), protein carbonyl and 8-OHdG were also reduced by UC-CM, indicating that UC-CM protected cells by reducing oxidative damage. Moreover, UC-CM significantly increased the expression of nuclear Nrf2 and its downstream enzyme HO1. The Nrf2 translocation inhibitor ML385 could inhibit the effect of UC-CM on the cell viability and aggregate of M337V. Our results suggest that UC-CM protect cells against M337V expression by its strong antioxidative effect via Nrf-2/HO-1 axis activation.

Umbilical cord mesenchymal stem cell-conditioned medium inhibits microglial activation to ameliorate neuroinflammation in amyotrophic lateral sclerosis mice and cell models.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease for which few effective therapeutic strategies are available. Increasing evidence indicates that neuroinflammation plays a significant role in ALS pathogenesis. Mesenchymal stem cell (MSC)-based therapy has been proposed for the treatment of neurodegenerative diseases, including ALS. In this study, we first demonstrated that systemic administration of conditioned medium derived from umbilical cord MSCs (UCMSC-CM) extends the lifespan of transgenic SOD1-G93A mice, a well-characterized model of familial ALS. Moreover, UCMSC-CM inhibits microglial activation and astrogliosis and alleviates the inflammatory milieu by reducing the release of proinflammatory cytokines and the expression of iNOS in the spinal cord. Using BV-2 cells overexpressing the SOD1-G93A mutant as an ALS cellular model, we uncovered that UCMSC-CM also suppresses the lipopolysaccharide (LPS)-induced inflammatory response, including reduced expression of proinflammatory cytokines and iNOS. Importantly, by culturing astrocytes alone in microglia-conditioned medium (MCM) or together with microglia in a transwell coculture system, we found that UCMSC-CM modulates the secretome of microglia exposed to inflammatory stimuli, thereby preventing the conversion of astrocytes to the A1 neurotoxic phenotype. This study revealed the anti-inflammatory properties of UCMSC-CM and its regulatory effect on glial activation in the treatment of neuroinflammation in ALS, providing strong evidence for the clinical application of UCMSC-CM.