Circ_0008657 regulates lung DNA damage induced by hexavalent chromium through the miR-203a-3p/ATM axis.

Hexavalent chromium [Cr (VI)] is an important environmental pollutant and may cause lung injury when inhaled into the human body. Cr (VI) is genotoxic and can cause DNA damage, although the underlying epigenetic mechanisms remain unclear. To simulate the real-life workplace exposure to Cr (VI), we used a novel exposure dose calculation method. We evaluated the effect of Cr (VI) on DNA damage in human bronchial epithelial cells (16HBE and BEAS-2B) by calculating the equivalent real-time exposure dose of Cr (VI) (0 to 10 µM) in an environmental population. Comet experiments and olive tail moment measurements revealed increased DNA damage in cells exposed to Cr (VI). Cr (VI) treatment increased nuclear γ-H2AX foci and γ-H2AX protein expression, and caused DNA damage in the lung tissues of mice. An effective Cr (VI) dose (6 µM) was determined and used for cell treatment. Cr (VI) exposure upregulated circ_0008657, and knockdown of circ_0008657 decreased Cr (VI)-induced DNA damage, whereas circ_0008657 overexpression had the opposite effect. Mechanistically, we found that circ_0008657 binds to microRNA (miR)-203a-3p and subsequently regulates ATM serine/threonine kinase (ATM), a key protein involved in homologous recombination repair downstream of miR-203a-3p, thereby regulating DNA damage induced by Cr (VI). The present findings suggest that circ_0008657 competitively binds to miR-203a-3p to activate the ATM pathway and regulate the DNA damage response after environmental chemical exposure in vivo and in vitro.

Circ0087385 promotes DNA damage in benzo(a)pyrene-induced lung cancer development by upregulating CYP1A1.

Increasing environmental genotoxic chemicals have been shown to induce epigenetic alterations. However, the interaction between genetics and epigenetics in chemical carcinogenesis is still not fully understood. Here, we constructed an in vitro human lung carcinogenesis model (16HBE-T) by treating human bronchial epithelial cells with a typical significant carcinogen benzo(a)pyrene (BaP). We identified a novel circular RNA, circ0087385, which was overexpressed in 16HBE-T and human lung cancer cell lines, as well as in lung cancer tissues and serum exosomes from lung cancer patients. The upregulated circ0087385 after exposure to BaP promoted DNA damage in the early stage of chemical carcinogenesis and affected the cell cycle, proliferation, and apoptosis of the malignantly transformed cells. Overexpression of circ0087385 enhanced the expression of cytochrome P450 1A1 (CYP1A1), which is crucial for metabolically activating BaP. Interfering with circ0087385 or CYP1A1 reduced the levels of ultimate carcinogen benzo(a)pyrene diol epoxide (BPDE) and BPDE-DNA adducts. Interfering with CYP1A1 partially reversed the DNA damage induced by high expression of circ0087385, as well as decreased the level of BPDE and BPDE-DNA adducts. These findings provide novel insights into the interaction between epigenetics and genetics in chemical carcinogenesis which are crucial for understanding the epigenetic and genetic toxicity of chemicals.

Cadmium toxicity and autophagy: a review.

Cadmium (Cd) is an important environmental pollutant that poses a threat to human health and represents a critical component of air pollutants, food sources, and cigarette smoke. Cd is a known carcinogen and has toxic effects on the environment and various organs in humans. Heavy metals within an organism are difficult to biodegrade, and those that enter the respiratory tract are difficult to remove. Autophagy is a key mechanism for counteracting extracellular (microorganisms and foreign bodies) or intracellular (damaged organelles and proteins that cannot be degraded by the proteasome) stress and represents a self-protective mechanism for eukaryotes against heavy metal toxicity. Autophagy maintains cellular homeostasis by isolating and gathering information about foreign chemicals associated with other molecular events. However, autophagy may trigger cell death under certain pathological conditions, including cancer. Autophagy dysfunction is one of the main mechanisms underlying Cd-induced cytotoxicity. In this review, the toxic effects of Cd-induced autophagy on different human organ systems were evaluated, with a focus on hepatotoxicity, nephrotoxicity, respiratory toxicity, and neurotoxicity. This review also highlighted the classical molecular pathways of Cd-induced autophagy, including the ROS-dependent signaling pathways, endoplasmic reticulum (ER) stress pathway, Mammalian target of rapamycin (mTOR) pathway, Beclin-1 and Bcl-2 family, and recently identified molecules associated with Cd. Moreover, research directions for Cd toxicity regarding autophagic function were proposed. This review presents the latest theories to comprehensively reveal autophagy behavior in response to Cd toxicity and proposes novel potential autophagy-targeted prevention and treatment strategies for Cd toxicity and Cd-associated diseases in humans.

Temporal analysis of lung injury induced by real-ambient PM2 .5 exposure in mice.

Fine particulate matter (PM2.5 ) has been shown to induce lung injury. However, the pathophysiological mechanisms of PM2.5 -induced pulmonary injury after different exposure times are poorly understood. In this study, we exposed male ICR mice to a whole-body PM2.5 inhalation system at daily mean concentration range from 92.00 to 862.00 µg/m3 for 30, 60, and 90 days. We found that following prolonged exposure to PM2.5 , pulmonary injury was increasingly evident with significant histopathological alterations. Notably, the pulmonary inflammatory response and fibrosis caused by PM2.5 after different exposure times were closely associated with histopathological changes. In addition, PM2.5 exposure caused oxidative stress, DNA damage and impairment of DNA repair in a time-dependent manner in the lung. Importantly, exposure to PM2.5 eventually caused apoptosis in the lung through upregulation of cleaved-caspase-3 and downregulation of Bcl-2. Overall, our data demonstrated that PM2.5 led to pulmonary injury in a time-dependent manner via upregulation of proinflammatory and fibrosis-related genes, and activation of the DNA damage response. Our findings provided a novel perspective on the pathophysiology of respiratory diseases caused by airborne pollution.

Adverse event profile of CGRP monoclonal antibodies: findings from the FDA adverse event reporting database.

BACKGROUND: Four CGRP Monoclonal Antibodies (mAbs) have been approved for migraine prophylaxis by the Food and Drug Administration (FDA) since 2018. However, there are concerns about the safety of these four drugs for real-world use. OBJECTIVE: To compare the adverse event profiles of four CGRP-mAbs with FAERS data. METHODS: The study was based on records from the FAERS database. Only reports containing one of the active ingredients with CGRP-mAbs were included in this study. Disproportionality analyses including but not limited to reporting odds ratio (ROR) and information components (IC) were conducted to identify drug-AE associations. RESULTS: In total, 58110 reports were identified for CGRP-mAbs. 80 overlapping signals were disproportionately reported. They affected a range of organs and systems, including the gastrointestinal and cardiovascular systems, skin, and hair. Additionally, the rare cardiovascular adverse events were significantly different among the four CGRP-mAbs. CONCLUSION: We identified numerous shared underlying signals (overlapping signals) for CGRP-mAbs as suspected drugs in multiple systems and organs. The unlabeled common signals may indicate potential safety issues. In addition, the underlying safety signals varied among the four CGRP-mAbs, particularly in the cardiovascular system, and further studies are needed to confirm these associations and the potential clinical implications.

Fe3+ mediated shikonin and PPA coloaded liposomes induce robust immunogenic cell death by integrating ROS enhancement and GSH depletion.

Reactive oxygen species (ROS) can not only induce cellular oxidative stress, but also trigger antitumor immune response. However, single ROS generated therapy is usually not enough to induce efficient antitumor immune response. Furthermore, the adaptive antioxidant mechanisms coupled with overexpressed ROS can also decrease the antitumor capacity of ROS therapy. To circumvent this problem, we designed a synergistic strategy for inducing robust ROS based ICD effect by constructing a coloaded liposomes (PPA, Pyropheophorbide-alpha and SHK, shikonin) with Fe3+ gradient to simultaneously enhance ROS mediated oxidative stress and glutathione depletion. Interestingly, the coloaded liposome possesses an acid/GSH dual triggered release profile. More importantly, with the help of depleting GSH, LipoPS (coloaded liposome of SHK and PPA) can excite robust ROS and demonstrate synergistic antitumor efficacy with amplified ICD effect. Summarized, the established coloaded liposome LipoPS exhibits good therapeutic security and synergistic antitumor effect with strong antitumor immune activation, providing potential for further development.

Carbon black nanoparticles and cadmium co-exposure aggravates bronchial epithelial cells inflammation via autophagy-lysosome pathway.

Carbon black nanoparticles (CBNPs) and cadmium (Cd) are major components of various air pollutants and cigarette smoke. Autophagy and inflammation both play critical roles in understanding the toxicity of particles and their components, as well as maintaining body homeostasis. However, the effects and mechanisms of CBNPs and Cd (CBNPs-Cd) co-exposure on the human respiratory system remain unclear. In this study, a CBNPs-Cd exposure model was constructed to explore the respiratory toxicity and combined mechanism of these chemicals on the autophagy-lysosome pathway in the context of respiratory inflammation. Co-exposure of CBNPs and Cd significantly increased the number of autophagosomes and lysosomes in human bronchial epithelial cells (16HBE) and mouse lung tissues compared to the control group, as well as the groups exposed to CBNPs and Cd alone. Autophagic markers, LC3II and P62 proteins, were up-regulated in 16HBE cells and mouse lung tissues after CBNPs-Cd co-exposure. However, treatment with Cq inhibitor (an indicator of lysosomal acid environment) resulted in a substantial decreased co-localization fluorescence of LC3 and lysosomes in the CBNPs-Cd combination group compared with the CBNPs-Cd single and control groups. No difference in LAMP1 protein expression was observed among the exposed groups. Adding 3 MA alleviated inflammatory responses, while applying the Baf-A1 inhibitor aggravated inflammation both in vitro and in vivo following CBNPs-Cd co-exposure. Factorial analysis showed no interaction between CBNPs and Cd in their effects on 16HBE cells. We demonstrated that co-exposure to CBNPs-Cd increases the synthesis of autophagosomes and regulates the acidic environment of lysosomes, thereby inhibiting autophagy-lysosome fusion and enhancing the inflammatory response in both 16HBE cells and mouse lung. These findings provide evidence for a comprehensive understanding of the interaction between CBNPs and Cd in mixed pollutants, as well as for the prevention and control of occupational exposure to these two chemicals.

Intramuscularly injected long-acting testosterone-cholesterol prodrug suspension with three different particle sizes: extended in vitro release and enhanced in vivo safety.

The testosterone undecanoate oil solution is the most widely used injection of testosterone for long-acting effects on the market, whereas the formulation carries the potential risk of causing pulmonary vascular embolism, inflammation, and pain at the injection site. Therefore, a sustained-released long-acting injection of testosterone with strong security is urgently exploited. Herein, a poorly water-soluble testosterone-cholesterol prodrug (TST-Chol) was synthesized by esterification. The water solubility of TST-Chol was decreased by 644 folds in comparison to that of testosterone (TST). Moreover, suspensions of TST and TST-Chol were prepared and analyzed in vitro, utilizing three distinct particle sizes: small-sized nanocrystals (SNCs) measuring 300 nm, medium-sized microcrystals (MMCs) measuring 12 µm, and large-sized microcrystals (LMCs) measuring 20 µm. The findings from the in vitro release study indicated that the sustained release of the drug was significantly influenced by the solubility and particle sizes of the suspension. Notably, the suspensions with low water solubility and larger particle sizes exhibited a more desirable sustained-release effect in vitro. Furthermore, the study on pharmacokinetics exhibited that TST-Chol SNCs produced a sustained TST plasma concentration in vivo for up to 40 days and no obvious pathological changes in lung tissue were found. Our study indicated that solubility and particle sizes of suspensions had made a difference in pharmacokinetics and provided a valuable reference for the advancement of long-acting injections.

Economic burden attributable to healthcare-associated infections at western China hospitals: 6 Year, prospective cohort study.

OBJECTIVES: Healthcare-associated infections (HAIs) represent a major threat to patient safety and are associated with significant economic burden. Calculating the costs attributable to HAIs is challenging given the various sources of bias. Although HAIs as a reasonably preventable medical harm should have been closely linked to medical insurance incentives, there was little linkage between HAIs and medicare in western China owing to the lack of economic evaluation data. The present study aimed to generate estimates of the attributable costs associated with HAIs and the magnitude of costs growth. METHODS: In this cohort study designed horizontally and vertically from 2016 to 2022, we compared outcomes of randomly sampling patients with HAIs and individually matched patients without HAIs in two cohorts at a 6-year interval at 34 hospitals in western China. The primary outcome was the direct medical cost for the entire hospital stay, converted to US dollars ($ for the benchmark year), discounted at 3% annually, and estimated separately in the full analysis set (FAS) and the per protocol set (PPS). We used multiple linear regression to adjust the discounted costs and to assess subgroups effects within each cohort. We nested a dynamic vertical comparison of costs attributable to HAIs between the front and rear cohorts. RESULTS: A total of 230 patients with HAIs in 2016 and 204 patients with HAIs in 2022 were enrolled. After a 1:1 match, all 431 pairs were recruited as FAS, of which 332 pairs as PPS met all matching restrictions. Compared to the 2016 cohort in FAS, the patients with HAIs in 2022 had a significantly older age (64.40 ± 16.45 years), higher repeat hospitalization rate (65 [32.02%] of 203), and lower immune function (69 [33.99%] of 203). The discounted costs and adjusted-discounted costs for patients with HAIs in the 2022 cohort were found to be significantly higher than those of patients without HAIs (discounted costs: $5484.60 [IQR 8426.03] vs $2554.04(4530.82), P < 0.001; adjusted-discounted costs: $5235.90 [3772.12] vs $3040.21(1823.36), P < 0.001, respectively), and also higher than those of patients with HAIs in the 2016 cohort (discounted costs: $5484.60 [8426.03] vs $3553.00 [6127.79], P < 0.001; adjusted-discounted costs: $5235.90 [3772.12] vs $3703.82 [3159.14], P < 0.001, respectively). In vertical comparison of PPS, the incremental costs of the 2022 cohort are 1.48 times higher than those of the 2016 cohort ($964.63(4076.15) vs $652.43 [2533.44], P = 0.084). CONCLUSIONS: This meticulously designed study in western China has successfully and accurately examined the economic burden attributable to HAIs. Their rapidly increasing tendency poses a serious challenge to patients, hospitals, and the medical insurance. A closer linkage between HAIs and ongoing motivating system changes is urgently needed in western China.

Long non-coding RNAs mediate the association between short-term PM2.5 exposure and circulating biomarkers of systemic inflammation.

Although short-term fine particulate matter (PM2.5) exposure is associated with systemic inflammation, the effect of lncRNA on these association remains unknown. This study aims to investigate whether the plasma lncRNA mediate the effect of short-term PM2.5 exposure on systemic inflammation. In this cross-sectional study, plasma Clara cell protein 16 (CC16), interleukin 6 (IL-6), IL-8, tumor necrosis factor-α (TNF-α) and lncRNA expression levels were measured in 161 adults between March and April in 2018 in Shijiazhuang, China. PM2.5 concentrations were estimated 0-3 days prior to the examination date and the moving averages were calculated. Multiple linear regressions were used to evaluate the associations between PM2.5, the four biomarkers and lncRNA expression levels. Mediation analyses were performed to explore the potential roles of lncRNA expression in these associations. The median concentration of PM2.5 ranged from 39.65 to 60.91 mg/m3 across different lag days. The most significant effects on IL-6 and TNF-α per interquartile range increase in PM2.5 were observed at lag 0-3 days, with increases of 0.70 pg/mL (95% CI: 0.33, 1.07) and 0.21 pg/mL (95% CI: 0.06, 0.36), respectively. While the associations between PM2.5 and IL-8 (0.68 pg/mL, 95% CI: 0.34, 1.02) and CC16 (3.86 ng/mL, 95% CI: 1.60, 6.13) were stronger at lag 0 day. Interestingly, a negative association between PM2.5 and the expression of four novel lncRNAs (lnc-ACAD11-1:1, lnc-PRICKLE1-4:1, lnc-GPR39-7:2, and lnc-MTRNR2L12-3:6) were observed at each lag days. Furthermore, these lncRNAs mediated the effects of PM2.5 on the four biomarkers, with proportions of mediation ranged from 2.27% (95% CI: 1.19%, 9.82%) for CC16 to 35.60% (95% CI: 17.16%, 175.45%) for IL-6. Our findings suggested that plasma lncRNA expression mediat the acute effects of PM2.5 exposure on systematic inflammation. These highlight a need to consider circulating lncRNA expression as biomarkers to reduce health risks associated with PM2.5.

Benzo[a]pyrene-induced up-regulation of circ_0003552 via ALKBH5-mediated m6A modification promotes DNA damage in human bronchial epithelial cells.

Benzo [a]pyrene (B [a]P) is a widespread environmental chemical pollutant that has been linked to the development of various diseases. However, the specific mechanism of action remains unclear. In this study, human bronchial epithelial 16HBE and BEAS-2B cells were exposed to B [a]P at 0-32 µM to assess the DNA-damaging effects. B [a]P exposure resulted in elevated expression of γ-H2AX, a marker of DNA damage. The m6A RNA methylation assay showed that B [a]P exposure increased the extent of m6A modification and the demethylase ALKBH5 played an integral role in this process. Moreover, the results of the comet assay and Western blot analysis showed an increase in m6A modification mediated by ALKBH5 that promoted DNA damage. Furthermore, the participation of a novel circular RNA, circ_0003552, was assessed by high-throughput sequencing under the condition of high m6A modification induced by B [a]P exposure. In subsequent functional studies, an interference/overexpression system was created to confirm that circ_0003552 participated in regulation of DNA damage. Mechanistically, circ_0003552 had an m6A binding site that could regulate its generation. This study is the first to report that B [a]P upregulated circ_0003552 through m6A modification, thereby promoting DNA damage. These findings revealed that epigenetics played a key role in environmental carcinogen-induced DNA damage, and the quantitative changes it brought might provide an early biomarker for future medical studies of genetic-related diseases and a new platform for investigations of the interaction between epigenetics and genetics.

Novel Phenylethanoid Glycosides Improve Hippocampal Synaptic Plasticity via the Cyclic Adenosine Monophosphate-CREB-Brain-Derived Neurotrophic Growth Factor Pathway in APP/PS1 Transgenic Mice.

INTRODUCTION: Alzheimer's disease (AD) is a major public health concern worldwide, but there are still no drugs available that treat it effectively. Previous studies have shown that phenylethanoid glycosides have pharmacological effects, which include anti-AD properties, but the underlying mechanisms by which they ameliorate AD symptoms remain unknown. METHODS: In this study, we used an APP/PS1 AD mouse model to explore the function and mechanisms underlying savatiside A (SA) and torenoside B (TB) in the treatment of AD. SA or TB (100 mg·kg-1·d-1) was orally administered to 7-month-old APP/PS1 mice for 4 weeks. Cognitive and memory functions were measured using behavioral experiments (including the Morris water maze test and the Y-maze spontaneous alternation test). Molecular biology experiments (including Western blotting, immunofluorescence, and enzyme-linked immunosorbent assays) were used to detect any corresponding changes in signaling pathways. RESULTS: The results showed that SA or TB treatment could significantly reduce cognitive impairment in APP/PS1 mice. We also showed that chronic treatment with SA/TB could prevent spine loss, synaptophysin immunoreactivity, and neuronal loss in mice, thereby improving synaptic plasticity and moderating learning and memory deficits. SA/TB administration also promoted the expression of synaptic proteins in APP/PS1 mouse brains and upregulated phosphorylation of proteins in the cyclic adenosine monophosphate (cAMP)/CREB/brain-derived neurotrophic growth factor (BDNF) pathway that are responsible for synaptic plasticity. Additionally, chronic SA/TB treatment increased the levels of BDNF and nerve growth factor (NGF) in the brains of APP/PS1 mice. Both astrocyte and microglia volumes, as well as the generation of amyloid ß, were also decreased in SA/TB-treated APP/PS1 mice compared to control APP/PS1 mice. CONCLUSION: In summary, SA/TB treatment was associated with activation of the cAMP/CREB/BDNF pathway and increased BDNF and NGF expression, indicating that SA/TB improves cognitive functioning via nerve regeneration. SA/TB is a promising candidate drug for the treatment of AD.

Analyze and simulate an individualized nutritional computing system for multidisciplinary teams in nutritional support therapy.

To explore the efficiency of nutritional support therapy . Pharmacists led the construction of an individualized nutritional computing system and were involved in the process of treatment. After obtaining relevant professional knowledge and instruction on how to operate the system, MDT members intervened in the incorrect treatment process during nutritional support therapy. The Department of Radiation Oncology and the Intensive Care Unit (ICU) were selected as pilot departments to compare and analyze the rationality of nutrition risk screening and the use of enteral nutrition (EN) and parenteral nutrition (PN) in treatment before and after intervention. The individualized nutritional computing system significantly improved work efficiency, promoted nutrition risk screening, and saved 10-15 minutes in the treatment of each patient. After intervention in the Department of Radiation Oncology, the use rate of Total Nutrient Admixture (TNA) increased by 7.17%, and the single-bottle infusion rate of PN preparation decreased by 17.94% in patients at risk of malnutrition. The use rate of EN and single-bottle infusion rate of PN preparation in patients without risk of malnutrition decreased by 15.17% and 20.81%, respectively. Overall, 98.75% of ICU patients were at risk of malnutrition. The use rates of EN and TNA increased by 12.79% and 12.14%, respectively, and the single-bottle infusion rate of PN preparation decreased by 10.06%. Streamlined and mobile MDT, the use of an individualized nutritional computing system, and the effective work of pharmacists in the process significantly improved the efficiency and rationality of nutritional support therapy .

Sodium aescinate inhibits microglia activation through NF-κB pathway and exerts neuroprotective effect.

Background: Microglia are resident immune cells of the central nervous system that sense environmental changes and maintain central nervous system homeostasis. Dysfunctional microglia produce toxic mediators that lead to neuronal death. Recent studies suggest that Sodium Aescinate has a neuroprotective effect. However, it is unclear whether Sodium Aescinate exerts neuroprotective effects by inhibiting activation of microglia. Method: Traumatic brain injury and lipopolysaccharide neuroinflammation model were used to evaluate the microglia activation in vivo. BV2 and primary microglia cells were used to assess the microglia activation in vitro. Molecular docking technique was used to predict the binding energy of Sodium Aescinate to NF-κB signaling pathway proteins. Result: Sodium Aescinate inhibited microglial activation in-vivo and in-vitro. Sodium Aescinate inhibited the activation of microglia in Traumatic brain injury and lipopolysaccharide mouse models. Sodium Aescinate also inhibited the expression of inflammatory proteins in BV2 and primary microglia cells. Western blot experiment showed that SA inhibited the activation of NF-κB pathway in BV2 and primary microglia cells. Molecular docking results also showed that Sodium Aescinate had a better affinity with the core protein of the NF-κB pathway. Western blot identified that SA inhibited activation of NF-κB pathway. In Traumatic brain injury model and conditioned medium experiment, Sodium Aescinate pretreatment inhibited inflammation and protected neuron. Conclusion: Our study confirmed that the protection effects of Sodium Aescinate on neurons by inhibiting microglia activation through NF-κB pathway.

circCIMT Silencing Promotes Cadmium-Induced Malignant Transformation of Lung Epithelial Cells Through the DNA Base Excision Repair Pathway.

Changes in gene expression in lung epithelial cells are detected in cancer tissues during exposure to pollutants, highlighting the importance of gene-environmental interactions in disease. Here, a Cd-induced malignant transformation model in mouse lungs and bronchial epithelial cell lines is constructed, and differences in the expression of non-coding circRNAs are analyzed. The migratory and invasive abilities of Cd-transformed cells are suppressed by circCIMT. A significant DNA damage response is observed after exposure to Cd, which increased further following circCIMT-interference. It is found that APEX1 is significantly down-regulated following Cd exposure. Furthermore, it is demonstrated that circCIMT bound to APEX1 during Cd exposure to mediate the DNA base excision repair (BER) pathway, thereby reducing DNA damage. In addition, simultaneous knockdown of both circCIMT and APEX1 promotes the expression of cancer-related genes and malignant transformation after long-term Cd exposure. Overall, these findings emphasis the importance of genetic-epigenetic interactions in chemical-induced cancer transformation.

Circ_0089282 inhibits carbon black nanoparticle-induced DNA damage by promoting DNA repair protein in the lung.

Inhalation of carbon black nanoparticles (CBNPs) can impair lung tissue and cause DNA damage, but the epigenetic mechanism responsible for these effects is still unclear. We explored the role of circular RNAs (circRNAs) in DNA damage induced by CBNPs in the lung. Human bronchial epithelial cell lines (16HBE and BEAS-2B) were treated with 0, 5, 10, 20, 40, or 80 µg/ml CBNPs for 24, 48, and 72 h, and BALB/c mice were exposed to 8 and 80 µg/d CBNPs for 14 days to establish in vitro and vivo models of CBNP exposure, respectively. We found that CBNPs caused DNA double-strand breaks in the lung. Using high-throughput sequencing and quantitative real-time PCR to identify CBNP-related circRNAs, we identified a novel circRNA (circ_0089282) that was overexpressed in the CBNP-exposed group. We used gain-/loss-of-function approaches, RNA pulldown assays, and silver staining to explore the regulatory function of circ_0089282 and its interactions with targeted proteins. We found that circ_0089282 interference could increase CBNP-induced DNA damage, whereas overexpression resulted in the opposite. Circ_0089282 could directly bind to the fused in sarcoma (FUS) protein and positively regulate downstream DNA repair protein DNA ligase 4 (LIG4) through FUS. This regulatory effect of circRNA on DNA damage via promotion of LIG4 illustrated the interactions between genetics and epigenetics in toxicology.

Doxorubicin-isoniazid conjugate regulates immune response and tumor microenvironment to enhance cancer therapy.

Immune checkpoint inhibitors (ICIs) represent a new class of immunotherapy drugs, and are used to relieve immune suppression or enhance the immune response through the blockade of checkpoint ligands or receptors. ICIs have achieved great success in clinical cancer treatment. Monoamine oxidase A (MAOA) is a potent immune checkpoint of immunotherapy. Recently, it has been reported that MAOA inhibitors could enhance CD8+ T cell activity by upregulating 5-HT autocrine pathway in T cells. In this study, we synthesized doxorubicin (DOX) and isoniazid (INH, a MAOA inhibitor) conjugates through a pH sensitive hydrazone bond. Results of the in vivo studies showed that DOX-INH could effectively enhance the activity of CD8+ T cells and perform a synergistic anti-tumor effect with PD-L1 small molecular inhibitor (BMS202). In addition, in an orthotopic 4T1 breast cancer model, it was demonstrated that DOX-INH could inhibit the epithelial-mesenchymal transition process by blocking Shh, IL-6, and TGF-ß signaling pathways, thereby inhibiting the growth and metastasis of breast cancer. Thus, a simple and effective small molecule conjugate produced by the combination of a chemotherapy drug and a MAOA inhibitor shows broad prospect in cancer therapy.

Zn2+ loading as a critical contributor to the circ_0008553-mediated oxidative stress and inflammation in response to PM2.5 exposures.

Inflammation is a major adverse outcome induced by inhaled particulate matter with a diameter of ≤ 2.5 µm (PM2.5), and a critical trigger of most PM2.5 exposure-associated diseases. However, the key molecular events regulating the PM2.5-induced airway inflammation are yet to be elucidated. Considering the critical role of circular RNAs (circRNAs) in regulating inflammation, we predicted 11 circRNAs that may be involved in the PM2.5-induced airway inflammation using three previously reported miRNAs through the starBase website. A novel circRNA circ_0008553 was identified to be responsible for the PM2.5-activated inflammatory response in human bronchial epithelial cells (16HBE) via inducing oxidative stress. Using a combinatorial model PM2.5 library, we found that the synergistic effect of the insoluble core and loaded Zn2+ ions at environmentally relevant concentrations was the major contributor to the upregulation of circ_0008553 and subsequent induction of oxidative stress and inflammation in response to PM2.5 exposures. Our findings provided new insight into the intervention of PM2.5-induced adverse outcomes.

DNMT3A-mediated high expression of circ_0057504 promotes benzo[a]pyrene-induced DNA damage via the NONO-SFPQ complex in human bronchial epithelial cells.

Benzo[a]pyrene (B[a]P) is a class I carcinogen and hazardous environmental pollutant with genetic toxicity. Understanding the molecular mechanisms underlying genetic deterioration and epigenetic alterations induced by environmental contaminants may contribute to the early detection and prevention of cancer. However, the role and regulatory mechanisms of circular RNAs (circRNAs) in the B[a]P-induced DNA damage response (DDR) have not been elucidated. In this study, human bronchial epithelial cell lines (16HBE and BEAS-2B) were exposed to various concentrations of B[a]P, and BALB/c mice were treated with B[a]P intranasally. B[a]P exposure was found to induce DNA damage and upregulate circular RNA hsa_circ_0057504 (circ_0057504) expression in vitro and in vivo. In addition, B[a]P upregulated TMEM194B mRNA and circ_0057504 expression through inhibition of DNA methyltransferase 3 alpha (DNMT3A) expression in vitro. Modulation (overexpression or knockdown) of circ_0057504 expression levels using a lentiviral system in human bronchial epithelial cells revealed that circ_0057504 promoted B[a]P-induced DNA damage. RNA pull-down and western blot assays showed that circ_0057504 interacted with non-POU domain-containing octamer-binding (NONO) and splicing factor proline and glutamine rich (SFPQ) proteins and regulated formation of the NONO-SFPQ protein complex. Thus, our findings indicate that circ_0057504 acts as a novel regulator of DNA damage in human bronchial epithelial cells exposed to B[a]P. The current study reveals novel insights into the role of circRNAs in the regulation of genetic damage, and describes the effect and regulatory mechanisms of circ_0057504 on B[a]P genotoxicity.

A novel matrix metalloproteinases-cleavable hydrogel loading deferoxamine accelerates diabetic wound healing.

The hyperglycemia microenvironment of diabetic foot ulcer (DFU) led to impaired angiogenesis and delayed wound healing. An elevated matrix metalloproteinase (MMP) is one of the significant factors to delay healing. Herein, we designed a deferoxamine (DFO)-loaded MMP responsive hydrogel, thus promoting angiogenesis and accelerating wound healing by increasing the expression of hypoxia-inducible factor-1α (HIF-1α). Hyaluronic acid was modified with maleimide and grafted with MMP-cleavable peptides (HA-peptide). Then, HA-peptide was crosslinked with oxidized dextran (Dex-CHO) based on Schiff-base reaction. In vitro tests showed that the hydrogel had excellent swelling properties, degradation behavior, rheological characterization, and biocompatibility. Compared with an MMP-insensitive hydrogel, the MMP-cleavable hydrogel allowed for efficient release of DFO continuously within 24 h, which could address the problems of the extremely short half-life and neurotoxicity of DFO. In vivo experiments demonstrated that the hydrogel wound dressing facilitated faster wound epithelialization and accelerated angiogenesis in diabetic rats. Altogether, the DFO-loaded MMP-cleavable hydrogel may lead to a potential and novel treatment strategy of DFU.