Sunflower Pollen-Derived Microspheres Selectively Absorb DNA for microRNA Detection.

Herein, we report the finding that a naturally sunflower pollen-derived microspheres (HSECs) with hierarchical structures can selectively absorb polyC and polyA with high efficiency and affinity. HSECs exhibit the capability to selectively absorb polyC and polyA ssDNA under neutral and acidic conditions. It has been observed that the presence of metal cations, specifically Ca2+, enhances the absorption efficiency of HSECs. Mechanically, this absorption phenomenon can be attributed to both electrostatic interactions and cation-π interactions. Such an appealing property enables the functionalization of HSECs for broad potential biomedical applications, such as microRNA detection.

Framework Nucleic Acids Enabled Pulmonary Artery Endothelial Cell Growth Inhibition by Targeting microRNA-152.

Pulmonary artery vascular endothelial dysfunction plays a pivotal role in the occurrence and progression of pulmonary vascular remodeling (PVR). To address this, aberrantly expressed non-coding microRNAs (miRNAs) are excellent therapeutic targets in human pulmonary artery endothelial cells (HPAECs). Here, we discovered and validated the overexpression of miRNA-152 in HPAECs under hypoxia and its role in endothelial cell dysfunction. We constructed a framework nucleic acid nanostructure that harbors six protruding single-stranded DNA segments that can fully hybridize with miRNA-152 (DNT-152). DNT-152 was efficiently taken up by HPAECs with increasing time and concentration; it markedly induced apoptosis, and inhibited HPAEC growth under hypoxic conditions. Mechanistically, DNT-152 silenced miRNA-152 expression and upregulated its target gene Meox2, which subsequently inhibited the AKT/mTOR signaling pathway. These results indicate that miRNA-152 in HPAECs may be an excellent therapeutic target against PVR, and that framework nucleic acids with carefully designed sequences are promising nanomedicines for noncancerous cells and diseases.

Hyperglycemia and Correlated High Levels of Inflammation Have a Positive Relationship with the Severity of Coronavirus Disease 2019.

OBJECTIVE: Coronavirus disease 2019 (COVID-19) is a considerable global public health threat. This study sought to investigate whether blood glucose (BG) levels or comorbid diabetes are associated with inflammatory status and disease severity in patients with COVID-19. METHODS: In this retrospective cohort study, the clinical and biochemical characteristics of COVID-19 patients with or without diabetes were compared. The relationship among severity of COVID-19, inflammatory status, and diabetes or hyperglycemia was analyzed. The severity of COVID-19 in all patients was determined according to the diagnostic and treatment guidelines issued by the Chinese National Health Committee (7th edition). RESULTS: Four hundred and sixty-one patients were enrolled in our study, and 71.58% of patients with diabetes and 13.03% of patients without diabetes had hyperglycemia. Compared with patients without diabetes (n = 366), patients with diabetes (n = 95) had a higher leucocyte count, neutrophil count, neutrophil to lymphocyte ratio (NLR), and erythrocyte sedimentation rate (ESR). There was no association between severity of COVID-19 and known diabetes adjusted for age, sex, body mass index (BMI), known hypertension, and coronary heart disease. The leucocyte count, NLR, and C-reactive protein (CRP) level increased with increasing BG level. Hyperglycemia was an independent predictor of critical (OR 4.00, 95% CI 1.72-9.30) or severe (OR 3.55, 95% CI 1.47-8.58) COVID-19, and of increased inflammatory levels (high leucocyte count (OR 4.26, 95% CI 1.65-10.97), NLR (OR 2.76, 95% CI 1.24-6.10), and CRP level (OR 2.49, 95% CI 1.19-5.23)), after adjustment for age, sex, BMI, severity of illness, and known diabetes. CONCLUSION: Hyperglycemia was positively correlated with higher inflammation levels and more severe illness, and it is a risk factor for the increased severity of COVID-19. The initial measurement of plasma glucose levels after hospitalization may help identify a subset of patients who are predisposed to a worse clinical course.

Assembling Defined DNA Nanostructure with Nitrogen-Enriched Carbon Dots for Theranostic Cancer Applications.

DNA nanostructures as scaffolds for drug delivery, biosensing, and bioimaging are hindered by its vulnerability in physiological settings, less favorable of incorporating arbitrary guest molecules and other desirable functionalities. Noncanonical self-assembly of DNA nanostructures with small molecules in an alternative system is an attractive strategy to expand their applications in multidisciplinary fields and is rarely explored. This work reports a nitrogen-enriched carbon dots (NCDs)-mediated DNA nanostructure self-assembly strategy. Given the excellent photoluminescence and photodynamic properties of NCDs, the obtained DNA/NCDs nanocomplex holds great potential for bioimaging and anticancer therapy. NCDs can mediate DNA nanoprism (NPNCD ) self-assembly isothermally at a large temperature and pH range in a magnesium-free manner. To explore the suitability of NPNCD in potential biomedical applications, the cytotoxicity and cellular uptake efficiency of NPNCD are evaluated. NPNCD with KRAS siRNA (NPNCD K) is further conjugated for KRAS-mutated nonsmall cell lung cancer therapy. The NPNCD K shows excellent gene knockdown efficiency and anticancer effect in vitro. The current study suggests that conjugating NCDs with programmable DNA nanostructures is a powerful strategy to endow DNA nanostructures with new functionalities, and NPNCD may be a potential theranostic platform with further fine-tuned properties of CDs such as near-red fluorescence or photothermal activities.

Targeted Delivery of Rab26 siRNA with Precisely Tailored DNA Prism for Lung Cancer Therapy.

Programmable DNA nanostructures are a new class of biocompatible, nontoxic nanomaterials. Nevertheless, their application in the field of biomedical research is still in its infancy, especially as drug delivery vehicles for gene therapy. In this study, a GTPase Rab26 was investigated as a new potential therapeutic target using a precisely tailored DNA nanoprism for targeted lung cancer therapy. Specifically, a DNA nanoprism platform with tunable targeting and siRNA loading capability is designed and synthesized. The as-prepared DNA prisms were decorated with two functional units: a Rab26 siRNA as the drug and MUC-1 aptamers as a targeting moiety for non-small cell lung cancer. The number and position of both siRNA and MUC-1 aptamers can be readily tuned by switching two short, single-stranded DNA. Native polyacrylamide gel electrophoresis (PAGE) and dynamic light scattering technique (DLS) demonstrate that all nanoprisms with different functionalities are self-assembled with high yield. It is also found that the cellular uptake of DNA prisms is proportional to the aptamer number on each nanoprism, and the as-prepared DNA nanoprism show excellent anti-cancer activities and targeting capability. This study suggests that by careful design, self-assembled DNA nanostructures are highly promising, customizable, multifunctional nanoplatforms for potential biomedical applications, such as personalized precision therapy.

PK/PD modeling of Ceftiofur Sodium against Haemophilus parasuis infection in pigs.

BACKGROUND: Ceftiofur Sodium is widely used in China. Our aim was to determine Ceftiofur Sodium activity and optimize dosing regimens against the pathogen Haemophilus parasuis using an in vitro and ex vivo pharmacokinetics/pharmacodynamics modeling approach. By adopting these strategies, we wanted to extend the effective life of Ceftiofur Sodium in reduce drug-resistance in pigs. RESULTS: We established an H. parasuis infection model in pigs, and assessed the pharmacokinetics of Ceftiofur Sodium in both healthy and infected animals. After Ceftiofur Sodium (10 mg/kg, i.m.) administration to healthy and H. parasuis-infected pigs, plasma based desfuroylceftiofur (a metabolite of Ceftiofur Sodium) was measured by High Performance Liquid Chromatography. The pharmacokinetics of Ceftiofur Sodium (desfuroylceftiofur) was consistent with a two-compartment open model, with first-order absorption. We observed no significant differences (P > 0.05) in pharmacokinetic parameters between healthy and infected pigs. Pharmacodynamics data showed that Ceftiofur Sodium was highly inhibitory against H. parasuis, with MIC, MBC, and MPC values of 0.003125, 0.0125 and 0.032 µg/mL, respectively. Desfuroylceftiofur in plasma also had strong bactericidal activity. Almost all H. parasuis cultured in plasma medium of Ceftiofur Sodium-inoculated healthy pigs, at each time point, were killed within 24 h. A weaker antibacterial activity was measured in infected-pig plasma medium at 18, 24, 36, and 48 h, after Ceftiofur Sodium inoculation. Pharmacokinetic parameters were combined with ex vivo pharmacodynamic parameters, and the bacteriostatic effect (36.006 h), bactericidal effect (71.637 h) and clearance (90.619 h) within 24 h, were determined using the Hill equation. Dose-calculation equations revealed the optimal dose of Ceftiofur Sodium to be 0.599-1.507 mg/kg. CONCLUSIONS: There were no significant differences in Ceftiofur Sodium pharmacokinetic parameters between healthy and infected pigs, although pharmacokinetics/pharmacodynamics fitting curves showed obviously differences. The optimal dose of Ceftiofur Sodium was lower than recommended (3 mg/kg), which may provide improved treatments for Glässers disease, with lower drug-resistance possibility.

Endothelial Cell Inflammation and Barriers Are Regulated by the Rab26-Mediated Balance between ß2-AR and TLR4 in Pulmonary Microvessel Endothelial Cells.

Rab26 GTPase modulates the trafficking of cell surface receptors, such as G protein-coupled receptors including α2-adrenergic receptors in some cell types. However, the effect of Rab26 on ß2-adrenergic receptor (ß2-AR) trafficking or/and Toll-like receptor 4 (TLR4) expression in human pulmonary microvascular endothelial cells (HPMECs) is still unclear. Here, we investigated the role of Rab26 in regulating the expression of ß2-ARs and TLR4 in HPMECs and the effect of these receptors' imbalance on endothelial cell barrier function. The results showed that there was unbalance expression in these receptors, where ß2-AR expression was remarkably reduced, and TLR4 was increased on the cell membrane after lipopolysaccharide (LPS) treatment. Furthermore, we found that Rab26 overexpression not only upregulated ß2-ARs but also downregulated TLR4 expression on the cell membrane. Subsequently, the TLR4-related inflammatory response was greatly attenuated, and the hyperpermeability of HPMECs also was partially relived. Taken together, these data suggest that basal Rab26 maintains the balance between ß2-ARs and TLR4 on the cell surface, and it might be a potential therapeutic target for diseases involving endothelial barrier dysfunction.

Predictive Value of Combined LIPS and ANG-2 Level in Critically Ill Patients with ARDS Risk Factors.

To investigate the predictive value of the acute physiology and chronic health evaluation 2 (APACHE2) score and lung injury prediction score (LIPS) for acute respiratory distress syndrome (ARDS) when combined with biomarkers for this condition in patients with ARDS risk factors. In total, 158 Han Chinese patients with ARDS risk factors were recruited from the Respiratory and Emergency Intensive Care Units. The LIPS, APACHE2 score, primary diagnosis at admission, and ARDS risk factors were determined within 6 h of admission, and PaO2/FiO2 was determined on the day of admission. Blood was collected within 24 h of admission for the measurement of angiopoietin-2 (ANG-2), sE-selectin, interleukin-6 (IL-6), and interleukin-8 (IL-8) levels. ARDS was monitored for the next 7 days. Univariate and multivariate analyses and receiver operating characteristic (ROC) analyses were employed to construct a model for ARDS prediction. Forty-eight patients developed ARDS within 7 days of admission. Plasma ANG-2 level, sE-selectin level, LIPS, and APACHE2 score in ARDS patients were significantly higher than those in non-ARDS patients. ANG-2 level, LIPS, and APACHE2 score were correlated with ARDS (P < 0.001, P < 0.006, and P < 0.042, resp.). When the APACHE2 score was used in combination with the LIPS and ANG-2 level to predict ARDS, the area under the ROC curve (AUC) was not significantly increased. Compared to LIPS or ANG-2 alone, LIPS in combination with ANG-2 had significantly increased positive predictive value (PPV) and AUC for the prediction of ARDS. In conclusion, plasma ANG-2 level, LIPS, and APACHE2 score are correlated with ARDS. Combined LIPS and ANG-2 level displays favorable sensitivity, specificity, and AUC for the prediction of ARDS.

Activation of PPARγ inhibits pro-inflammatory cytokines production by upregulation of miR-124 in vitro and in vivo.

Peroxisome proliferator-activated receptor gamma (PPARγ) and miR-124 have been reported to play important roles in regulation of inflammation. However, the underlying anti-inflammatory mechanisms remain not well understood. In the present study, we demonstrated that the expression level of PPARγ is positively correlated with that of miR-124 in patients with sepsis. Activation of PPARγ upregulates miR-124 and in turn inhibits miR-124 target gene. PPARγ bound directly to PPRE in the miR-124 promoter region, and enhanced the promoter transcriptional activity. PPARγ-induced miR-124 is involved in the suppression of pro-inflammatory cytokine in vitro and in vivo. These results suggest that PPARγ-induced miR-124 inhibits the production of pro-inflammatory cytokines is a novel PPARγ anti-inflammatory mechanism and also indicate that miR-124 may be a potential therapeutic target for the treatment of inflammatory diseases.

Retrosynthetic Analysis-Guided Breaking Tile Symmetry for the Assembly of Complex DNA Nanostructures.

Current tile-based DNA self-assembly produces simple repetitive or highly symmetric structures. In the case of 2D lattices, the unit cell often contains only one basic tile because the tiles often are symmetric (in terms of either the backbone or the sequence). In this work, we have applied retrosynthetic analysis to determine the minimal asymmetric units for complex DNA nanostructures. Such analysis guides us to break the intrinsic structural symmetries of the tiles to achieve high structural complexities. This strategy has led to the construction of several DNA nanostructures that are not accessible from conventional symmetric tile designs. Along with previous studies, herein we have established a set of four fundamental rules regarding tile-based assembly. Such rules could serve as guidelines for the design of DNA nanostructures.

RIP140 down-regulation alleviates acute lung injury via the inhibition of LPS-induced PPARγ promoter methylation.

Seriously inflammatory response of the lungs can induce acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) which are serious public health threats due to their high patient morbidity and mortality. While RIP140 is known to modulate proinflammatory cytokine production during an inflammatory response, its role in ALI/ARDS is unclear. In this study, we examined RIP140 and PPARγ protein expression in RAW 264.7 cells and lung tissue following LPS-induced ALI. RIP140 shRNA adenoviral knockdown significantly elevated PPARγ expression, inhibited TNF-α, IL-1ß, and IL-6 production in vivo and in vitro. Conversely, treatment with a PPARγ antagonist (GW9662) reversed these outcomes. Furthermore, co-IP showed that endogenous and exogenous RIP140 interacted with DNMT3b in RAW 264.7 cells. Bisulfite conversion, pyrosequencing and activity assays demonstrated that PPARγ promoter methylation levels were increased and that PPARγ transcriptional activity was inhibited following LPS treatment in macrophages. Nevertheless, RIP140 knockdown reduced PPARγ promoter methylation levels and restored its transcriptional activity. These results indicate that RIP140 knockdown can inhibit the production of inflammation mediators and remit ALI via the repression of DNMT3b mediated PPARγ promoter methylation.

Bone morphogenic protein-2 regulates the myogenic differentiation of PMVECs in CBDL rat serum-induced pulmonary microvascular remodeling.

Hepatopulmonary syndrome (HPS) is characterized by an arterial oxygenation defect induced by intrapulmonary vasodilation (IPVD) that increases morbidity and mortality. In our previous study, it was determined that both the proliferation and the myogenic differentiation of pulmonary microvascular endothelial cells (PMVECs) play a key role in the development of IPVD. However, the molecular mechanism underlying the relationship between IPVD and the myogenic differentiation of PMVECs remains unknown. Additionally, it has been shown that bone morphogenic protein-2 (BMP2), via the control of protein expression, may regulate cell differentiation including cardiomyocyte differentiation, neuronal differentiation and odontoblastic differentiation. In this study, we observed that common bile duct ligation (CBDL)-rat serum induced the upregulation of the expression of several myogenic proteins (SM-α-actin, calponin, SM-MHC) and enhanced the expression levels of BMP2 mRNA and protein in PMVECs. We also observed that both the expression levels of Smad1/5 and the activation of phosphorylated Smad1/5 were significantly elevated in PMVECs following exposure to CBDL-rat serum, which was accompanied by the down-regulation of Smurf1. The blockage of the BMP2/Smad signaling pathway with Noggin inhibited the myogenic differentiation of PMVECs, a process that was associated with relatively low expression levels of both SM-α-actin and calponin in the setting of CBDL-rat serum exposure, although SM-MHC expression was not affected. These findings suggested that the BMP2/Smad signaling pathway is involved in the myogenic differentiation of the PMVECs. In conclusion, our data highlight the pivotal role of BMP2 in the CBDL-rat serum-induced myogenic differentiation of PMVECs via the activation of both Smad1 and Smad5 and the down-regulation of Smurf1, which may represent a potential therapy for HPS-induced pulmonary vascular remodeling.

Rab5-mediated VE-cadherin internalization regulates the barrier function of the lung microvascular endothelium.

The small GTPase Rab5 has been well defined to control the vesicle-mediated plasma membrane protein transport to the endosomal compartment. However, its function in the internalization of vascular endothelial (VE)-cadherin, an important component of adherens junctions, and as a result regulating the endothelial cell polarity and barrier function remain unknown. Here, we demonstrated that lipopolysaccharide (LPS) simulation markedly enhanced the activation and expression of Rab5 in human pulmonary microvascular endothelial cells (HPMECs), which is accompanied by VE-cadherin internalization. In parallel, LPS challenge also induced abnormal cell polarity and dysfunction of the endothelial barrier in HPMECs. LPS stimulation promoted the translocation of VE-cadherin from the plasma membrane to intracellular compartments, and intracellularly expressed VE-cadherin was extensively colocalized with Rab5. Small interfering RNA (siRNA)-mediated depletion of Rab5a expression attenuated the disruption of LPS-induced internalization of VE-cadherin and the disorder of cell polarity. Furthermore, knockdown of Rab5 inhibited the vascular endothelial hyperpermeability and protected endothelial barrier function from LPS injury, both in vitro and in vivo. These results suggest that Rab5 is a critical mediator of LPS-induced endothelial barrier dysfunction, which is likely mediated through regulating VE-cadherin internalization. These findings provide evidence, implicating that Rab5a is a potential therapeutic target for preventing endothelial barrier disruption and vascular inflammation.

Requirement of miR-9-dependent regulation of Myocd in PASMCs phenotypic modulation and proliferation induced by hepatopulmonary syndrome rat serum.

Hepatopulmonary syndrome (HPS) is characterized by a triad of severe liver disease, intrapulmonary vascular dilation and hypoxaemia. Pulmonary vascular remodelling (PVR) is a key feature of HPS pathology. Our previous studies have established the role of the pulmonary artery smooth muscle cell (PASMC) phenotypic modulation and proliferation in HPS-associated PVR. Myocardin, a robust transcriptional coactivator of serum response factor, plays a critical role in the vascular smooth muscle cell phenotypic switch. However, the mechanism regulating myocardin upstream signalling remains unclear. In this study, treatment of rat PASMCs with serum drawn from common bile duct ligation rats, which model symptoms of HPS, resulted in a significant increase in miR-9 expression correlated with a decrease in expression of myocardin and the phenotypic markers SM-α-actin and smooth muscle-specific myosin heavy chain (SM-MHC). Furthermore, miRNA functional analysis and luciferase reporter assay demonstrated that miR-9 effectively regulated myocardin expression by directly binding to its 3'-untranslated region. Both the knockdown of miR-9 and overexpression of myocardin effectively attenuated the HPS rat serum-induced phenotype switch and proliferation of PASMCs. Taken together, the findings of our present study demonstrate that miR-9 is required in HPS rat serum-induced phenotypic modulation and proliferation of PASMCs for targeting of myocardin and that miR-9 may serve as a potential therapeutic target in HPS.

MiR-206 controls the phenotypic modulation of pulmonary arterial smooth muscle cells induced by serum from rats with hepatopulmonary syndrome by regulating the target gene, annexin A2.

BACKGROUND: Hepatopulmonary syndrome (HPS) is a serious complication of advanced liver disease that is characterised by intrapulmonary vascular dilatation (IPVD) and arterial hypoxemia. Pulmonary vascular remodelling (PVR) is an important pathological feature of HPS, but the potential mechanisms underlying PVR remain undefined. Recent findings have established the essential role of changes in Annexin A2 (ANXA2) in controlling the phenotypic modulation of pulmonary artery smooth muscle cells (PASMCs) in PVR associated with HPS. However, the mechanism by which upstream signalling regulates ANXA2 is unclear. METHODS: In the present study, computational analysis was used to predict which miRNA might target the 3´-untranslated region (3´-UTR) of the ANXA2 mRNA. Real-time PCR and western blotting were performed to study the level of correlation between ANXA2 and the differentiation marker with the predicted miRNAs in PASMCs stimulated with serum from normal rats or those with HPS. Functional analysis of the miRNA and a luciferase reporter assay were performed to demonstrate that the predicted miRNA suppressed ANXA2 expression by directly targeting the predicted 3´-UTR site of the ANXA2 mRNA. RESULTS: Computational analysis predicted that miR-206 would target the 3´-UTR of ANXA2 mRNA. In HPS rat serum-stimulated PASMCs, the expression of miR-206 displayed an inverse correlation with ANXA2, while a positive correlation was observed with the phenotypic marker smooth muscle α-actin (SM α-actin). The miRNA functional analysis and luciferase reporter assay demonstrated that miR-206 effectively downregulated the expression of ANXA2 by binding to the 3´-UTR of the ANXA2 mRNA. Consistently, miR-206 effectively inhibited the HPS rat serum-induced phenotypic modulation and proliferation, while these effects were reversed in ANXA2-overexpressing PASMCs. CONCLUSION: This study demonstrates that miR-206 inhibits the HPS rat serum-induced phenotypic modulation and proliferation in PASMCs by down-regulating ANXA2 gene expression.

Directed self-assembly of DNA tiles into complex nanocages.

Tile-based self-assembly is a powerful method in DNA nanotechnology and has produced a wide range of well-defined nanostructures. But the resulting structures are relatively simple. Increasing the structural complexity and the scope of the accessible structures is an outstanding challenge in molecular self-assembly. A strategy to partially address this problem by introducing flexibility into assembling DNA tiles and employing directing agents to control the self-assembly process is presented. To demonstrate this strategy, a range of DNA nanocages have been rationally designed and constructed. Many of them can not be assembled otherwise. All of the resulting structures have been thoroughly characterized by gel electrophoresis and cryogenic electron microscopy. This strategy greatly expands the scope of accessible DNA nanostructures and would facilitate technological applications such as nanoguest encapsulation, drug delivery, and nanoparticle organization.

Visible light-driven C/O-g-C3N4 activating peroxydisulfate to effectively inactivate antibiotic resistant bacteria and inhibit the transformation of antibiotic resistance genes: Insights on the mechanism.

Antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) dissemination within water pose a serious threat to public health. Herein, C and O dual-doped g-C3N4 (C/O-g-C3N4) photocatalyst, fabricated via calcination treatment, was utilized to activate peroxydisulfate (PDS) to investigate the disinfection effect on tetracycline-resistant Escherichia coli and the transformation frequency of ARGs. As a result, approximately 7.08 log E. coli were inactivated, and 72.36 % and 53.96 % of antibiotics resistance gene (tetB) and 16 S rRNA were degraded respectively within 80 min. Futhermore, the transformation frequency was reduced to 0.8. Characterization and theoretical results indicated that C and O doping in g-C3N4 might lead to the electronic structure modulation and band gap energy reduction, resulting in the production of more free radicals. The mechanism analysis revealed that C/O-g-C3N4 exhibited a lower adsorption energy and reaction energy barrier for PDS compared to g-C3N4. This was beneficial for the homolysis of O-O bonds, forming SO4•- radicals. The attack of the generated active species led to oxidative stress in cells, resulting in damage to the electron transport chain and inhibition of ATP production. Our findings disclose a valuable insight for inactivating ARB, and provide a prospective strategy for ARGs dissemination in water contamination.

Tobramycin-mediated self-assembly of DNA nanostructures for targeted treatment of Pseudomonas aeruginosa-infected lung inflammation.

Pseudomonas aeruginosa (PA) is one of the most common multidrug-resistant pathogens found in clinics, often manifesting as biofilms. However, due to the emergence of superbugs in hospitals and the overuse of antibiotics, the prevention and treatment of PA infections have become increasingly challenging. Utilizing DNA nanostructures for packaging and delivering antibiotics presents an intervention strategy with significant potential. Nevertheless, construction of functional DNA nanostructures with multiple functionalities and enhanced stability in physiological settings remains challenging. In this study, the authors propose a magnesium-free assembly method that utilizes tobramycin (Tob) as a mediator to assemble DNA nanostructures, allowing for the functionalization of DNA nanostructures by combining DNA and antibiotics. Additionally, our study incorporates maleimide-modified DNA into the nanostructures to act as a targeting moiety specifically directed towards the pili of PA. The targeting ability of the constructed functional DNA nanostructure significantly improves the local concentration of Tob, thereby reducing the side effects of antibiotics. Our results demonstrate the successful construction of a maleimide-decorated Tob/DNA nanotube (NTTob-Mal) for the treatment of PA-infected lung inflammation. The stability and biocompatibility of NTTob-Mal are confirmed, highlighting its potential for clinical applications. Furthermore, its specificity in recognizing and adhering to PA has been validated. In vitro experiments have shown its efficacy in inhibiting PA biofilm formation, and in a murine model, NTTob-Mal has exhibited significant therapeutic effectiveness against PA-induced pneumonia. In summary, the proposed antibiotic drug-mediated DNA nanostructure assembly approach holds promise as a novel strategy for targeted treatment of PA infections.

Rab26 alleviates sepsis-induced immunosuppression as a master regulator of macrophage ferroptosis and polarization shift.

Macrophage dysfunction is a significant contributor to more than 70 % of sepsis-related deaths, specifically secondary bacterial infections, during the immunosuppression stage of sepsis. Nevertheless, the role of Rab26 in this context remains unclear. In this study, we observed a substantial decrease in Rab26 expression in macrophages during the immunosuppressive phase of sepsis, which was also found to be suppressed by high extracellular levels of HMGB1. During the progression of sepsis, Rab26 deficiency promotes a polarization shift from the M1 to the M2-like phenotype in macrophages, rendering them susceptible to ferroptosis. Subsequent experimentation has revealed that Rab26 deficiency facilitates the degradation of GPX4, thereby aggravating macrophage ferroptosis through the upregulation of levels of lipid ROS, MDA, and ferrous iron induced by RSL3, a ferroptosis inducer. Additionally, Rab26-deficient mice in the immunosuppressed phase of sepsis exhibit heightened susceptibility to secondary infections, leading to exacerbated lung tissue damage and increased mortality rate. Overall, these findings indicate that Rab26 plays a crucial role in sepsis-induced macrophage immunosuppression by regulating macrophage ferroptosis and polarization. Hence, it represents a potential novel target for sepsis therapy.

Sunflower pollen-derived microcapsules adsorb light and bacteria for enhanced antimicrobial photothermal therapy.

Bacterial infection is one of the most serious clinical complications, with life-threatening outcomes. Nature-inspired biomaterials offer appealing microscale and nanoscale architectures that are often hard to fabricate by traditional technologies. Inspired by the light-harvesting nature, we engineered sulfuric acid-treated sunflower sporopollenin exine-derived microcapsules (HSECs) to capture light and bacteria for antimicrobial photothermal therapy. Sulfuric acid-treated HSECs show a greatly enhanced photothermal performance and a strong bacteria-capturing ability against Gram-positive bacteria. This is attributed to the hierarchical micro/nanostructure and surface chemistry alteration of HSECs. To test the potential for clinical application, an in situ bacteria-capturing, near-infrared (NIR) light-triggered hydrogel made of HSECs and curdlan is applied in photothermal therapy for infected skin wounds. HSECs and curdlan suspension that spread on bacteria-infected skin wounds of mice first capture the local bacteria and then form hydrogels on the wound upon NIR light stimulation. The combination shows a superior antibacterial efficiency of 98.4% compared to NIR therapy alone and achieved a wound healing ratio of 89.4%. The current study suggests that the bacteria-capturing ability and photothermal properties make HSECs an excellent platform for the phototherapy of bacteria-infected diseases. Future work that can fully take advantage of the hierarchical micro/nanostructure of HSECs for multiple biomedical applications is highly promising and desirable.