Intestinal Colonized Silkworm Chrysalis-Like Probiotic Composites for Multi-Crossed Comprehensive Synergistic Therapy of Inflammatory Bowel Disease.

Inspired by the timely emergence of silkworm pupae from their cocoons, silkworm chrysalis-like probiotic composites (SCPCs) are developed for the comprehensive therapy of inflammatory bowel disease (IBD), in which probiotics are enveloped as the "pupa" in a sequential layering of silk sericin (SS), tannic acid (TA), and polydopamine, akin to the protective "cocoon". Compared to unwrapped probiotics, these composites not only demonstrate exceptional resistance to the harsh gastrointestinal environment and exhibit over 200 times greater intestinal colonization but also safeguard probiotics from the damage of IBD environment while enabling probiotics sustained release. The probiotics, in synergy with SS and TA, provide a multi-crossed comprehensive therapy for IBD that simultaneously addresses various pathological features of IBD, including intestinal barrier disruption, elevated pro-inflammatory cytokines, heightened oxidative stress, and disturbances in the intestinal microbiota. SCPCs exhibit remarkable outcomes, including a 9.7-fold reduction in intestinal permeability, an 8.9-fold decrease in IL-6 levels, and a 2.9-fold reduction in TNF-α levels compared to uncoated probiotics. Furthermore, SCPCs demonstrate an impressive 92.25% reactive oxygen species clearance rate, significantly enhance the richness of beneficial intestinal probiotics, and effectively diminish the abundance of pathogenic bacteria, indicating a substantial improvement in the overall therapeutic effect of IBD.

A Cationic Metal-Organic Framework to Scavenge Cell-Free DNA for Severe Sepsis Management.

Circulating cell-free DNA (cfDNA) released by damaged cells causes inflammation and has been associated with the progression of sepsis. One proposed strategy to treat sepsis is to scavenge this inflammatory circulating cfDNA. Here, we develop a cfDNA-scavenging nanoparticle (NP) that consists of cationic polyethylenimine (PEI) of different molecular weight grafted to zeolitic imidazolate framework-8 (PEI-g-ZIF) in a simple one-pot process. PEI-g-ZIF NPs fabricated using PEI 1800 and PEI 25k but not PEI 600 suppressed cfDNA-induced TLR activation and subsequent nuclear factor kappa B pathway activity. PEI 1800-g-ZIF NPs showed greater inhibition of cfDNA-associated inflammation and multiple organ injury than naked PEI 1800 (lacking ZIF), and had greater therapeutic efficacy in treating sepsis. These results indicate that PEI-g-ZIF NPs acts as a "nanotrap" that improves upon naked PEI in scavenging circulating cfDNA, reducing inflammation, and reversing the progression of sepsis, thus providing a novel strategy for sepsis treatment.

ROS-responsive fluorinated polyethyleneimine vector to co-deliver shMTHFD2 and shGPX4 plasmids induces ferroptosis and apoptosis for cancer therapy.

Ferroptosis is a newly discovered non-apoptotic cell death form but its therapeutic efficacy triggered by traditional iron-based nanomaterials or classic drug inducers has been far from satisfactory due to the high glutathione (GSH) level in cancer cells and insufficient lipid peroxide production. Here we reported a ferroptosis/apoptosis combinational therapy by depleting GSH and downregulating GPX4 to disrupt redox homeostasis and amplify ferroptosis-related oxidation effect. In this study, we developed reactive oxygen species (ROS)-responsive serum-resistant nanoparticles with thioketal-crosslinked fluorinated polyethyleneimine 1.8K (TKPF) as the core, which were wrapped with hyaluronic acid (HA) as the shell (TKPFH NP) to co-deliver shGPX4 and shMTHFD2 plasmids for cancer treatment. The highly efficient and tumor-selective gene carrier TKPFH NPs revealed outstanding transfection efficiency (∼100 %) and sustained the efficiency (∼50 %) even in media containing 90 % FBS. Mediated by HA, TKPFH NPs actively targeted CD44 receptors, thus enabling efficient uptake by tumor cells and experiencing surface charge conversion to induce subsequent lysosomal escape. Then the TKPF NPs were effectively disintegrated by the abundant ROS in cancer cells, which facilitated the release of plasmids and avoided the cytotoxicity of cationic polymers. shGPX4 plasmid induced ferroptosis by producing ROS and lipid peroxides via downregulating GPX4, while shMTHFD2 triggered apoptosis by modulating NADPH/NADP and depleting GSH of the cancer cells. Moreover, GSH consumption caused by shMTHFD2 indirectly suppressed GPX4 and further augmented ferroptosis, showing synergistic anticancer effect against B16-F10 cells. Taken together, the rationally designed dual-gene loaded TKPFH NPs provided a safe and high-performance platform for enhanced ferroptosis-apoptosis combined anticancer efficacy based on gene therapy. STATEMENT OF SIGNIFICANCE: The therapeutic efficacy of ferroptosis has been far from satisfactory due to high GSH level and insufficient lipid peroxide production in cancer cells. Herein, we reported a ferroptosis/apoptosis combinational therapy by depleting GSH and downregulating GPX4 to disrupt redox homeostasis and amplify ferroptosis-related oxidation effect. ROS-responsive serum-resistant nanoparticles were fabricated with thioketal-crosslinked fluorinated PEI 1.8K (TKPF) as the core and hyaluronic acid (HA) as the shell (TKPFH NP) to co-deliver shGPX4 and shMTHFD2 plasmids. The shGPX4 plasmid induced ferroptosis by producing ROS and lipid peroxides via downregulating GPX4, while shMTHFD2 triggered apoptosis by modulating NADPH/NADP and depleting GSH. The rationally designed dual-gene loaded TKPFH NPs provided a safe and high-performance platform aimed for enhanced ferroptosis-apoptosis combined anticancer efficacy.

Nanoparticulate cell-free DNA scavenger for treating inflammatory bone loss in periodontitis.

Periodontitis is a common type of inflammatory bone loss and a risk factor for systemic diseases. The pathogenesis of periodontitis involves inflammatory dysregulation, which represents a target for new therapeutic strategies to treat periodontitis. After establishing the correlation of cell-free DNA (cfDNA) level with periodontitis in patient samples, we test the hypothesis that the cfDNA-scavenging approach will benefit periodontitis treatment. We create a nanoparticulate cfDNA scavenger specific for periodontitis by coating selenium-doped hydroxyapatite nanoparticles (SeHANs) with cationic polyamidoamine dendrimers (PAMAM-G3), namely G3@SeHANs, and compare the activities of G3@SeHANs with those of soluble PAMAM-G3 polymer. Both G3@SeHANs and PAMAM-G3 inhibit periodontitis-related proinflammation in vitro by scavenging cfDNA and alleviate inflammatory bone loss in a mouse model of ligature-induced periodontitis. G3@SeHANs also regulate the mononuclear phagocyte system in a periodontitis environment, promoting the M2 over the M1 macrophage phenotype. G3@SeHANs show greater therapeutic effects than PAMAM-G3 in reducing proinflammation and alveolar bone loss in vivo. Our findings demonstrate the importance of cfDNA in periodontitis and the potential for using hydroxyapatite-based nanoparticulate cfDNA scavengers to ameliorate periodontitis.

A nanoparticulate dual scavenger for targeted therapy of inflammatory bowel disease.

A therapeutic strategy that targets multiple proinflammatory factors in inflammatory bowel disease (IBD) with minimal systemic side effects would be attractive. Here, we develop a drug-free, biodegradable nanomedicine that acts against IBD by scavenging proinflammatory cell-free DNA (cfDNA) and reactive oxygen species (ROS). Polyethylenimine (PEI) was conjugated to antioxidative diselenide-bridged mesoporous organosilica nanoparticles (MONs) to formulate nanoparticles (MON-PEI) that exhibited high cfDNA binding affinity and ROS-responsive degradation. In ulcerative colitis and Crohn's disease mouse colitis models, orally administered MON-PEI accumulated preferentially in the inflamed colon and attenuated colonic and peritoneal inflammation by alleviating cfDNA- and ROS-mediated inflammatory responses, allowing a reduced dose frequency and ameliorating colitis even after delayed treatment. This work suggests a new nanomedicine strategy for IBD treatment.

A dual luminescent sensor coordination polymer for simultaneous determination of ascorbic acid and tryptophan.

Simultaneous high sensitivity detection of biomolecules is important for research in medicine, living cells and environmental samples. In this work, a water stable coordination polymer, [Cd2(bptc)(4,4'-bpy)(H2O)3]ˑH2O 1 (H4bptc = 2,3,3',4'-biphenyl tetracarboxylic acid, 4,4'-bpy = 4,4'-bipyridine), was designed and successfully synthesized as a luminescent sensor for simultaneous recognition of Ascorbic Acid (AA) and L-Tryptophan (L-Trp) based on luminescent -OFF and -ON, respectively. Importantly, the proposed sensing system showed an excellent performance with high KSV values of 4.85 × 104 M-1, 9.60 × 107 M-1 and low limit of detection (LOD) of 0.28 nM, 63 nM, respectively. In addition, the probable mechanisms are also discussed. The luminescent quenching behavior by AA can be mainly attributed to the static resonance energy transfer between complex 1 and the analytes. Whereas the enhancing effect of L-Trp comes from the intrinsic strong luminescence for L-Trp itself and photo-competitive mechanism between CP 1 sensor and L-Trp, supposedly. In addition, the repeatability of both systems were also investigated.

Treatment of severe sepsis with nanoparticulate cell-free DNA scavengers.

Severe sepsis represents a common, expensive, and deadly health care issue with limited therapeutic options. Gaining insights into the inflammatory dysregulation that causes sepsis would help develop new therapeutic strategies against severe sepsis. In this study, we identified the crucial role of cell-free DNA (cfDNA) in the regulation of the Toll-like receptor 9-mediated proinflammatory pathway in severe sepsis progression. Hypothesizing that removing cfDNA would be beneficial for sepsis treatment, we used polyethylenimine (PEI) and synthesized PEI-functionalized, biodegradable mesoporous silica nanoparticles with different charge densities as cfDNA scavengers. These nucleic acid-binding nanoparticles (NABNs) showed superior performance compared with their nucleic acid-binding polymer counterparts on inhibition of cfDNA-induced inflammation and subsequent multiple organ injury caused by severe sepsis. Furthermore, NABNs exhibited enhanced accumulation and retention in the inflamed cecum, along with a more desirable in vivo safety profile. Together, our results revealed a key contribution of cfDNA in severe sepsis and shed a light on the development of NABN-based therapeutics for sepsis therapy, which currently remains intractable.

Bioactive carbon dots direct the osteogenic differentiation of human bone marrow mesenchymal stem cells.

Bone marrow mesenchymal stem cells (BMSCs) have been the focus of bone regeneration due to their excellent osteogenic potential and abundant source. However, the high-cost and low-efficiency differentiation of BMSCs into functional osteoblasts limits their clinical application. It is desirable to develop bioactive materials to integrate efficient differentiation and traceable properties in a biocompatible manner for MSC-based therapy. In this study, a new kind of bioactive carbon dot (CD) was facilely fabricated through a one-step hydrothermal method from adenosine and aspirin. These bioactive CDs were cytocompatible and biosafe with the capability of long-term fluorescent tracking of human bone marrow mesenchymal stem cells (hBMSCs). Notably, the presence of bioactive CDs triggered and directed a series of events that followed the temporal pattern of osteogenic differentiation through the promotion of osteogenic transcription and enhancement of matrix mineralization. Moreover, cells with bioactive CDs exhibited more effective osteogenic differentiation behavior than cells treated with either adenosine or aspirin alone. Overall, these findings clearly showed that adenosine and aspirin-based CDs can direct osteogenic differentiation of hBMSCs in the absence of any external osteoinductive factors. The unique properties of bioactive CDs could provide insight into their potential for achieving efficient and safe MSC-based therapy.

Effects of oral implants with miR­122­modified cell sheets on rat bone marrow mesenchymal stem cells.

The aim of the present study was to regulate the transformation of bone marrow mesenchymal stem cells (BMMSCs) to osteoblasts to promote bone formation and osseointegration surrounding oral implants. BMMSCs were cultured using the whole bone marrow adherence method. Cell surface markers were detected by flow cytometry, and multi­lineage differentiation potential was detected by osteogenic and adipogenic tests. miR­122­modified cell sheets were prepared by non­viral transfection and complexed with micro­arc titanium oxide implants to construct a gene­modified tissue­engineered implant, with its surface morphology observed by scanning electron microscopy (SEM). In vitro osteogenic activity of the implant was determined by alkaline phosphatase (ALP), Sirius Red, alizarin red staining, polymerase chain reaction and western blot analysis. The BMMSCs were spindle­ or triangular­shaped. Surface markers, cluster of differentiation 29 (CD29), CD90 and CD105 were positively expressed, whereas blood cell markers CD34, CD45 and CD31 were negatively expressed. Osteogenic staining exhibited deposition of calcified nodules, while adipogenic staining demonstrated the formation of lipid droplets. miR­122 modification significantly enhanced the in vitro osteogenic activity of the sheets. On day 3 of osteogenic induction, runt-related transcription factor 2, osterix, osteocalcin, collagen I, ALP and bone morphogenetic protein 2 expression levels of the experimental group were 2.0, 3.1, 4.6, 3.2, 10.5 and 4.5 times those of the blank control group, respectively. SEM imaging of the modified sheet demonstrated close adhesion and fitting between abundant cellular and extracellular matrices, and the porous surface of the implant. In vitro osteogenesis of the complex was promoted and accelerated. Thus, miR­122 effectively promoted osteogenic differentiation of the BMMSC sheet. Therefore, it is feasible to construct gene­modified tissue­engineered implants by complexing miR­122­modified sheets with micro­arc titanium oxide implants.

Antibacterial and biodegradable tissue nano-adhesives for rapid wound closure.

BACKGROUND: Although various organic tissue adhesives designed to facilitate would healing are gaining popularity in diverse clinical applications, they present significant inherent limitations, such as rejection, infections, toxicity and/or excessive swelling. It is highly desirable to develop efficient, biocompatible and anti-bacterial tissue adhesives for skin wound healing. PURPOSE: Inspired by the fact that inorganic nanoparticles can directly glue tissues through the "nanobridging effect", herein disulfide bond-bridged nanosilver-decorated mesoporous silica nanoparticles (Ag-MSNs) was constructed as an effective and safe tissue adhesive with antibacterial and degradable properties for wound closure and healing. MATERIALS AND METHODS: Ag-MSNs was fabricated by controlled reduce of ultrasmall nanosilvers onto the both surface and large pore of biodegradable MSNs. The obtained MSNs were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and measurement of size distribution, zeta potential, and mesopore properties. Furthermore, adhesion strength test, anti-bacterial assessment, mouse skin wound model, and MTT assays were used to investigate the tissue adhesive property, antibacterial effect, biodegradability and biocompatibility of the Ag-MSNs. RESULTS: Ag-MSNs exhibited not only strong adhesive properties but also excellent antibacterial activities than that of MSNs. Importantly, this antibacterial nano-adhesive achieved rapid and efficient closure and healing of wounds in comparison to sutures or MSNs in a mouse skin wound model. Furthermore, Ag-MSNs with fast degradable behavior caused little cellular toxicity and even less systemic toxicity during wound healing. CONCLUSION: Our findings suggest that biodegradable Ag-MSNs can be employed as the next generation of nano-adhesives for rapid wound closure and aesthetic wound healing.

Redox/pH dual-controlled release of chlorhexidine and silver ions from biodegradable mesoporous silica nanoparticles against oral biofilms.

BACKGROUND: Oral plaque biofilms pose a threat to periodontal health and are challenging to eradicate. There is a growing belief that a combination of silver nanoparticles and chlorhexidine (CHX) is a promising strategy against oral biofilms. PURPOSE: To overcome the side effects of this strategy and to exert maximum efficiency, we fabricated biodegradable disulfide-bridged mesoporous silica nanoparticles (MSNs) to co-deliver silver nanoparticles and CHX for biofilm inhibition. MATERIALS AND METHODS: CHX-loaded, silver-decorated mesoporous silica nanoparticles (Ag-MSNs@CHX) were fabricated after CHX loading, and the pH- and glutathione-responsive release profiles of CHX and silver ions along with their mechanism of degradation were systematically investigated. Then, the efficacy of Ag-MSNs@CHX against Streptococcus mutans and its biofilm was comprehensively assessed by determining the minimum inhibitory concentration, minimum bactericidal concentration, minimal biofilm inhibitory concentration, and the inhibitory effect on S. mutans biofilm formation. In addition, the biosafety of nanocarriers was evaluated by oral epithelial cells and a mouse model. RESULTS: The obtained Ag-MSNs@CHX possessed redox/pH-responsive release properties of CHX and silver ions, which may be attributed to the redox-triggered matrix degradation mechanism of exposure to biofilm-mimetic microenvironments. Ag-MSNs@CHX displayed dose-dependent antibacterial activity against planktonic and clone formation of S. mutans. Importantly, Ag-MSNs@CHX had an increased and long-term ability to restrict the growth of S. mutans biofilms compared to free CHX. Moreover, Ag-MSNs@CHX showed less cytotoxicity to oral epithelial cells, whereas orally administered Ag-MSNs exhibited no obvious toxic effects in mice. CONCLUSION: Our findings constitute a highly effective and safe strategy against biofilms that has a good potential as an oral biofilm therapy.

The shape effect of magnetic mesoporous silica nanoparticles on endocytosis, biocompatibility and biodistribution.

Although the aspect ratio (AR) play a crucial role in determining biological effects of homogeneous nanomaterials, studies available concerning how the shape contributes to biological effect of heterogeneous nanomaterials is limited. To systematically clarify the shape influence on the endocytosis, biocompatibility and biodistribution of magnetic mesoporous silica nanoparticles (M-MSNPs), three FITC-labeled M-MSNPs with different aspect ratio (AR=1, 2, and 4) were specifically designed and constructed through altering the ratios of CTAB/TEOS in a modified so-gel method. We have demonstrated that long-rod M-MSNP2 possessed higher intracellular internalization amount than the short-rod M-MSNP1 and the sphere-like M-MSNP0 in both cancer cells and normal cells due to the difference in the endocytosis pathways. However, there are no significant shape effects on biocompatibility including cytotoxicity and hemolytic rate. Moreover, biodistribution in HepG2 tumor-bearing mice showed that M-MSNPs administrated intravenously were mainly presented in reticuloendothelial system (RES) organs including liver, spleen and kidney. In particular, sphere-like M-MSNP0 were easily trapped in the liver, while long-rod M-MSP2 exhibited more retention in the spleen. It is worth noting that rod-like M-MSNPs are preferentially accumulated in tumor sites than sphere-like M-MSNPs, indicating an improved drug delivery efficacy in cancer therapy. Our findings may provide useful data for deeply understanding the interaction between the different shapes and biological behavior of M-MSNPs, which is expected to give rise to a new generation of heterogeneous M-MSNPs with significantly enhanced efficacy and safety for the cancer theranostics. STATEMENT OF SIGNIFICANCE: In this work, we systematically clarified the shape influence on the endocytosis, biocompatibility and biodistribution of homogeneous nanomaterials. We have demonstrated that rod-like magnetic mesoporous silica nanoparticles (M-MSNPs) were capable of higher intracellular internalization and tumor accumulation than sphere-like M-MSNPs, which was expected to give rise to a new generation of heterogeneous M-MSNPs with significantly enhanced efficacy and safety for the cancer theranostics.

Noninvasive theranostic imaging of HSV-TK/GCV suicide gene therapy in liver cancer by folate-targeted quantum dot-based liposomes.

Theranostics is emerging as a popular strategy for cancer therapy; thanks to the development of nanotechnology. In this work, we have combined an HSV-TK/GCV suicide gene system and near-infrared quantum dots, as the former is quite effective in liver cancer treatment and the latter facilitates tumor imaging. A folate-modified theranostic liposome (FL/QD-TK) was developed, which is composed of an HSV-TK suicide gene covalently coupling with near-infrared fluorescent CdSeTe/ZnS core/shell quantum dots. The liver cancer-targeting and biosafety of FL/QD-TK were studied in vitro and in vivo. FL/QD-TK exhibited highly specific tumor imaging and strong inhibition of the folate receptor-overexpressed Bel-7402 mouse xenografts without systematic toxicity. This study may shed light on gene delivery and targeted cancer therapy.