Acid-resistant ROS-responsive hyperbranched polythioether micelles for ulcerative colitis therapy

Inhalable and bioactive lipid-nanomedicine based on bergapten for targeted acute lung injury therapy via orchestrating macrophage polarization

Acute lung injury (ALI) or its more severe form, acute respiratory distress syndrome, is a life-threatening disease closely associated with an imbalance of M1/M2 macrophage polarization. However, current therapeutic strategies for ALI are controversial due to their side effects, restricted administration routes, or poor targeted delivery. The development of herbal medicine has uncovered numerous anti-inflammatory compounds potentially beneficial for ALI therapy. One such compound is the bergapten, a coumarin, which has been isolated from Ficus simplicissima Lour. However, it's been used as an anti-cancer drug and it's effects on ALI remain unexplored. The poor solubility and biodistribution of bergapten heavily limit its application. In this timely report, we developed a bioactive and lung-targeting lipid-nanomedicine by integrating bergapten and DPPC liposome, named as Ber-lipo. A comprehensive series of in vitro experiments confirmed the anti-inflammatory effects of Ber-lipo and its protective roles in maintaining the homeostasis of macrophage polarization and epithelial-endothelial integrity. In a lipopolysaccharide (LPS)-induced ALI mouse model, Ber-lipo can target inflamed lungs and significantly improve lung edema, tissue injury, and pulmonary function, relieve body weight loss, pulmonary permeability, and proinflammatory status, and especially maintain a balance of M1/M2 macrophage polarization. Furthermore, RNA sequencing analysis showed Ber-lipo's potential in effectively treating inflammatory lung diseases such as pneumonia, inhibiting proinflammatory signals, and altering the transcriptome of M1/M2 macrophages-associated genes in lung tissues. Molecular docking and Western blot analyses validated that Ber-lipo suppressed the activation of the TLR4/MyD88/NF-κB signaling axis responsible for ALI progression. In conclusion, this study demonstrates for the first time that new inhalable nanomedicine (Ber-lipo) can target inflamed lungs and ameliorates ALI by reprogramming macrophage polarization to an anti-inflammatory state via inactivating the TLR4/MyD88/NF-κB pathway, hence providing a promising strategy for enhanced ALI therapy in the clinic.

Preparation, characterization, pharmacokinetics and ulcerative colitis treatment of hyperoside-loaded mixed micelles

At present, ulcerative colitis (UC) has become a global disease due to its high incidence. Hyperoside (HYP) is a naturally occurring flavonoid compound with many pharmacological effects. This study aimed to develop HYP-loaded mixed micelles (HYP-M) to improve oral bioavailability of HYP and to evaluate its therapeutic effect on UC. The prepared HYP-M exhibited stable physical and chemical properties, smaller particle size (PS) (21.48 ± 1.37 nm), good polydispersity index (PDI = 0.178 ± 0.013), negative Zeta potential (ZP) (- 20.00 ± 0.48 mV) and high entrapment rate (EE) (89.59 ± 2.03%). In vitro release and in vivo pharmacokinetic results showed that HYP-M significantly increased the releasing rate of HYP, wherein its oral bioavailability was 4.15 times higher than that of free HYP. In addition, HYP-M was more effective in the treatment of UC than free HYP. In conclusion, HYP-M could serve as a novel approach to improve bioavailability and increase anti-UC activity of HYP.

Dual-ROS Sensitive Moieties Conjugate Inhibits Curcumin Oxidative Degradation for Colitis Precise Therapy

Curcumin, a natural bioactive polyphenol with diverse molecular targets, is well known for its anti-oxidation and anti-inflammatory potential. However, curcumin exhibits low solubility (<1 µg mL-1), poor tissue-targeting ability, and rapid oxidative degradation, resulting in poor bioavailability and stability for inflammatory therapy. Here, poly(diselenide-oxalate-curcumin) nanoparticle (SeOC-NP) with dual-reactive oxygen species (ROS) sensitive chemical moieties (diselenide and peroxalate ester bonds) is fabricated by a one-step synthetic strategy. The results confirmed that dual-ROS sensitive chemical moieties endowed SeOC-NP with the ability of targeted delivery of curcumin and significantly suppress oxidative degradation of curcumin for high-efficiency inflammatory therapy. In detail, the degradation amount of curcumin for SeOC is about 4-fold lower than that of free curcumin in an oxidative microenvironment. As a result, SeOC-NP significantly enhanced the antioxidant activity and anti-inflammatory efficacy of curcumin in vitro analysis by scavenging intracellular ROS and suppressing the secretion of nitric oxide and pro-inflammatory cytokines. In mouse colitis models, orally administered SeOC-NP can remarkably alleviate the symptoms of IBD and maintain the homeostasis of gut microbiota. This work provided a simple and effective strategy to fabricate ROS-responsive micellar and enhance the oxidation stability of medicine for precise therapeutic inflammation.

Oral administration of Huanglian-Houpo herbal nanoemulsion loading multiple phytochemicals for ulcerative colitis therapy in mice

How to achieve stable co-delivery of multiple phytochemicals is a common problem. This study focuses on the development, optimization and characterization of Huanglian-HouPo extract nanoemulsion (HLHPEN), with multiple components co-delivery, to enhance the anti-ulcerative colitis (UC) effects. The formulation of HLHPEN was optimized by pseudo-ternary phase diagram combined with Box-Behnken design. The physicochemical properties of HLHPEN were characterized, and its anti-UC activity was evaluated in DSS-induced UC mice model. Based on preparation process optimization, the herbal nanoemulsion HLHPEN was obtained, with the droplet size, PDI value, encapsulation efficiency (EE) for 6 phytochemicals (berberine, epiberberine, coptisine, bamatine, magnolol and honokiol) of 65.21 ± 0.82 nm, 0.182 ± 0.016, and 90.71 ± 0.21%, respectively. The TEM morphology of HLHPEN shows the nearly spheroidal shape of particles. The optimized HLHPEN showed a brownish yellow milky single-phase and optimal physical stability at 25 °C for 90 days. HLHPEN exhibited the good particle stability and gradual release of phytochemicals in SGF and SIF, to resist the destruction of simulated stomach and small intestine environment. Importantly, the oral administration of HLHPEN significantly restored the shrunk colon tissue length and reduced body weight, ameliorated DAI value and colon histological pathology, decreased the levels of inflammatory factors in DSS-induced UC mice model. These results demonstrated that HLHPEN had a significant therapeutic effect on DSS-induced UC mice, as a potential alternative UC therapeutic agent.

Responsive nanosystems for targeted therapy of ulcerative colitis: Current practices and future perspectives

The pharmacological approach to treating gastrointestinal diseases is suffering from various challenges. Among such gastrointestinal diseases, ulcerative colitis manifests inflammation at the colon site specifically. Patients suffering from ulcerative colitis notably exhibit thin mucus layers that offer increased permeability for the attacking pathogens. In the majority of ulcerative colitis patients, the conventional treatment options fail in controlling the symptoms of the disease leading to distressing effects on the quality of life. Such a scenario is due to the failure of conventional therapies to target the loaded moiety into specific diseased sites in the colon. Targeted carriers are needed to address this issue and enhance the drug effects. Conventional nanocarriers are mostly readily cleared and have nonspecific targeting. To accumulate the desired concentration of the therapeutic candidates at the inflamed area of the colon, smart nanomaterials with responsive nature have been explored recently that include pH responsive, reactive oxygen species responsive (ROS), enzyme responsive and thermo - responsive smart nanocarrier systems. The formulation of such responsive smart nanocarriers from nanotechnology scaffolds has resulted in the selective release of therapeutic drugs, avoiding systemic absorption and limiting the undesired delivery of targeting drugs into healthy tissues. Recent advancements in the field of responsive nanocarrier systems have resulted in the fabrication of multi-responsive systems i.e. dual responsive nanocarriers and derivitization that has increased the biological tissues and smart nanocarrier's interaction. In addition, it has also led to efficient targeting and significant cellular uptake of the therapeutic moieties. Herein, we have highlighted the latest status of the responsive nanocarrier drug delivery system, its applications for on-demand delivery of drug candidates for ulcerative colitis, and the prospects are underpinned.

A guide to modern methods for poly(thio)ether synthesis using Earth-abundant metals

Polyethers and polythioethers have a long and storied history dating back to the start of polymer science as a distinct field. As such, these materials have been utilized in a wide range of commercial applications and fundamental studies. The breadth of their material properties and the contexts in which they are applied is ultimately owed to their diverse monomer pre-cursors, epoxides and thiiranes, respectively. The facile polymerization of these monomers, both historically and contemporaneously, across academia and industry, has occurred through the use of Earth-abundant metals as catalysts and/or initiators. Despite this, polymerization methods for these monomers are underutilized compared to other monomer classes like cyclic olefins, vinyls, and (meth)acrylates. We feel a focused review that clearly outlines the benefits and shortcomings of extant synthetic methods for poly(thio)ethers along with their proposed mechanisms and quirks will help facilitate the utilization of these methods and by extension the unique polymer materials they create. Therefore, this Feature Article briefly describes the applications of poly(thio)ethers before discussing the feature-set of each poly(thio)ether synthetic method and qualitatively scoring them on relevant metrics (e.g., ease-of-use, molecular weight control, etc.) to help would-be poly(thio)ether-makers find an appropriate synthetic approach. The article is concluded with a look ahead at the future of poly(thio)ether synthesis with Earth-abundant metals.

In-vitro and in-vivo evaluation and anti-colitis activity of esculetin-loaded nanostructured lipid carrier decorated with DSPE-MPEG2000

OBJECTIVE

Encapsulation of esculetin into DSPE-MPEG2000 carrier was performed to improve its water solubility and oral bioavailability, as well as enhance its anti-inflammatory effect on a mouse model of ulcerative colitis that was induced with dextran sulphate sodium (DSS).

METHODS

We determined the in-vitro and in-vivo high-performance liquid chromatographic (HPLC) analysis method of esculetin; Esculetin-loaded nanostructure lipid carrier (Esc-NLC) was prepared using a thin-film dispersion method, wherein a particle size analyser was used to measure the particle size (PS) and zeta potential (ZP) of the Esc-NLC, while a transmission electron microscope (TEM) was employed to observe its morphology. Also, HPLC was used to measure its drug loading (DL), encapsulation efficiency (EE) and the in-vitro release of the preparation, as well as investigate the pharmacokinetic parameters. In addition, its anti-colitis effect was evaluated via histopathological examination of HE-stained sections and detection of the concentrations of tumour necrosis factor-alpha (TNF-α), interleukin (IL)-1 beta (β), and IL-6 in serum with ELISA kits.

RESULTS

The PS of Esc-NLC was 102.29 ± 0.63 nm with relative standard deviation (RSD) of 1.08% (with poly-dispersity index-PDI of 0.197 ± 0.023), while the ZP was -15.67 ± 1.39 mV with RSD of 1.24%. Solubility of esculetin was improved coupled with prolonged release time. Its pharmacokinetic parameters were compared with that of free esculetin, wherein the maximum concentration of the drug in plasma was increased by 5.5 times. Of note, bioavailability of the drug was increased by 1.7 times, while the half-life was prolonged by 2.4 times. In the anti-colitis efficacy experiment, the mice in Esc and Esc-NLC groups exhibited significantly reduced levels of TNF-α, IL-1β, and IL-6 in their sera comparable to the DSS group. Colon histopathological examination revealed that mice with ulcerative colitis in both Esc and Esc-NLC groups displayed improved inflammation, amid the Esc-NLC groups having the best prophylactic treatment effect.

CONCLUSION

Esc-NLC could ameliorate DSS-induced ulcerative colitis by improving bioavailability, prolonging drug release time and regulating cytokine release. This observation confirmed the potential of Esc-NLC to reduce inflammation in ulcerative colitis, albeit the need for follow-up research to verify the application of this strategy to clinical treatment of ulcerative colitis.

Reactive oxygen species-responsive nanocarrier ameliorates murine colitis by intervening colonic innate and adaptive immune responses

Ulcerative colitis (UC) is a chronic or relapsing inflammatory disease with limited therapeutic outcomes. Pterostilbene (PSB) is a polyphenol-based anti-oxidant that has received extensive interest for its intrinsic anti-inflammatory and anti-oxidative activities. This work aims to develop a reactive oxygen species (ROS)-responsive, folic acid (FA)-functionalized nanoparticle (NP) for efficient PSB delivery to treat UC. The resulting PSB@NP-FA had a nano-scaled diameter of 231 nm and a spherical shape. With ROS-responsive release and ROS-scavenging properties, PSB@NP could effectively scavenge H2O2, thereby protecting cells from H2O2-induced oxidative damage. After FA modification, the resulting PSB@NP-FA could be internalized by RAW 264.7 and Colon-26 cells efficiently and preferentially localized to the inflamed colon. In dextran sulfate sodium (DSS)-induced colitis models, PSB@NP-FA showed a prominent ROS-scavenging capacity and anti-inflammatory activity, therefore relieving murine colitis effectively. Mechanism results suggested that PSB@NP-FA ameliorated colitis by regulating dendritic cells (DCs), promoting macrophage polarization, and regulating T cell infiltration. Both innate and adaptive immunity were involved. More importantly, the combination of the PSB and dexamethasone (DEX) enhanced the therapeutic efficacy of colitis. This ROS-responsive and ROS-scavenging nanocarrier represents an alternative therapeutic approach to UC. It can also be used as an enhancer for classic anti-inflammatory drugs.

Reactive oxygen species-responsive polymer drug delivery systems

Applying reactive polymer materials sensitive to biological stimuli has recently attracted extensive research interest. The special physiological effects of reactive oxygen species (ROS) on tumors or inflammation and the application of ROS-responsive polymers as drug-delivery systems in organisms have attracted much attention. ROS is a vital disease signal molecule, and the unique accumulation of ROS-responsive polymers in pathological sites may enable ROS-responsive polymers to deliver payload (such as drugs, ROS-responsive prodrugs, and gene therapy fragments) in a targeted fashion. In this paper, the research progress of ROS-responsive polymers and their application in recent years were summarized and analyzed. The research progress of ROS-responsive polymers was reviewed from the perspective of nanoparticle drug delivery systems, multi-responsive delivery systems, and ROS-responsive hydrogels. It is expected that our work will help understand the future development trends in this field.

Caffeic Acid-Conjugated Budesonide-Loaded Nanomicelle Attenuates Inflammation in Experimental Colitis

Ulcerative colitis is a multifactorial disease of the gastrointestinal tract which is caused due to chronic inflammation in the colon; it usually starts from the lower end of the colon and may spread to other portions of the large intestine, if left unmanaged. Budesonide (BUD) is a synthetically available second-generation corticosteroidal drug with potent local anti-inflammatory activity. The pharmacokinetic properties, such as extensive first-pass metabolism and quite limited bioavailability, reduce its therapeutic efficacy. To overcome the limitations, nanosized micelles were developed in this study by conjugating stearic acid with caffeic acid to make an amphiphilic compound. The aim of the present study was to evaluate the pharmacological potential of BUD-loaded micelles in a mouse model of dextran sulfate sodium-induced colitis. Micelles were formulated by the solvent evaporation method, and their physicochemical characterizations show their spherical shape under microscopic techniques like atomic force microscopy, transmission electron microscopy, and scanning electron microscopy. The in vitro release experiment shows sustained release behavior in physiological media. These micelles show cytocompatible behavior against hTERT-BJ cells up to 500 μg/mL dose, evidenced by more than 85% viable cells. BUD-loaded micelles successfully normalized the disease activity index and physical observation of colon length. The treatment with BUD-loaded micelles alleviates the colitis severity as analyzed in histopathology and efficiently, overcoming the disease severity via downregulation of various related cytokines (MPO, NO, and TNF-α) and inflammatory enzymes such as COX-2 and iNOS. Results of the study suggest that BUD-loaded nano-sized micelles effectively attenuate the disease conditions in colitis.

Protective mechanisms of Zanthoxylum bungeanum essential oil on DSS-induced ulcerative colitis in mice based on a colonic mucosal transcriptomic approach

The ameliorative effects on ulcerative colitis (UC) as well as the related mechanisms of the essential oil derived from the edible herb Zanthoxylum bungeanum Maxim (ZBEO) have been demonstrated herein. Based on GC-MS analysis, 45 volatile compounds in ZBEO were determined for its quality control. In vitro studies showed that after pretreatment with ZBEO, the disordered expression levels of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) and an anti-inflammatory cytokine (IL-10) on colon epithelial NCM460 cells induced by lipopolysaccharide (LPS) could be reversed. Additionally, oral administration of ZBEO significantly alleviated colitis in dextran sulfate sodium (DSS)-induced UC mice, including body weight loss, colon length shortening, disease activity index and colonic pathological damage. Furthermore, to uncover the anti-UC mechanisms of ZBEO, analysis of transcriptomes by next-generation sequencing technology was performed to explore the RNA genetic variation on colon tissues. Based on GO analysis and KEGG pathway analysis, a series of genetic pathways involved in the protective role of ZBEO against UC were determined. As a result, ZBEO treatment could decrease the expression of VCAM-1, TLR8, IL-1β and IL-11 mRNA as verified by qRT-PCR, which are involved in these potential genetic pathways. In conclusion, ZBEO administration would be a medicinal or dietary supplementation strategy for ulcerative colitis treatment.

Colon-specific delivery of isoliquiritigenin by oral edible zein/caseate nanocomplex for ulcerative colitis treatment

Although a natural anti-inflammatory ingredient, isoliquiritigenin (ISL), plays an effective role in ulcerative colitis (UC) treatment, a series of drawbacks still limit its clinical application, including the poor solubility, instability in gastrointestinal tract, and rapid elimination rate of ISL. Zein-based NPs display the benefits on drug loading and delivery, whereas with the poor stability. In this study, an edible nano-system composed by zein/caseinate complex was fabricated for the colon-targeting delivery of ISL, to improve its colon retention and anti-UC effects. The optimized ISL loaded zein/caseinate NPs (ISL@NPs) were prepared by single-factor design by anti-solvent precipitation method, and then characterized. The improved cellular uptake of ISL@NPs on NCM460 and RAW 264.7 cells was evaluated in vitro. The colon tissue permeability and retention capacity in vivo, and the anti-UC efficacy of ISL@NPs in DSS-induce UC were implemented. As a result, ISL@NPs with the high drug loading efficiency of 9.39% ± 0.26%, the average particle diameter of 137.32 ± 2.54 nm, exhibited the pH-sensitive stability in the different simulated gastrointestinal buffer. Compared with free ISL, ISL@NPs showed significantly higher cellular uptake ability in NCM460 and RAW 264.7 cells. Based on in vivo imaging system, zein/caseinate NPs showed the prolonged colonic retention and the enhanced penetration into the colonic epithelium. Finally, the oral administration of ISL@NPs could effectively alleviate the UC-related symptoms, down-regulate the production of pro-inflammatory factors, and reduce the infiltration of macrophages and neutrophils in colon tissues. In this study, an oral colon-specific nano-system, composed with the natural compound and edible materials, was developed as the promising alternatives in the prevention and treatment of UC.

The in vivo fate of polymeric micelles

This review aims to provide a systemic analysis of the in vivo, as well as subcellular, fate of polymeric micelles (PMs), starting from the entry of PMs into the body. Few PMs are able to cross the biological barriers intact and reach the circulation. In the blood, PMs demonstrate fairly good stability mainly owing to formation of protein corona despite controversial results reported by different groups. Although the exterior hydrophilic shells render PMs "long-circulating", the biodistribution of PMs into the mononuclear phagocyte systems (MPS) is dominant as compared with non-MPS organs and tissues. Evidence emerges to support that the copolymer poly(ethylene glycol)-poly(lactic acid) (PEG-PLA) is first broken down into pieces of PEG and PLA and then remnants to be eliminated from the body finally. At the cellular level, PMs tend to be internalized via endocytosis due to their particulate nature and disassembled and degraded within the cell. Recent findings on the effect of particle size, surface characteristics and shape are also reviewed. It is envisaged that unraveling the in vivo and subcellular fate sheds light on the performing mechanisms and gears up the clinical translation of PMs.

Oral administration of turmeric-derived exosome-like nanovesicles with anti-inflammatory and pro-resolving bioactions for murine colitis therapy

BACKGROUND

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) characterized by diffuse inflammation of the colonic mucosa and a relapsing and remitting course. The current therapeutics are only modestly effective and carry risks for unacceptable adverse events, and thus more effective approaches to treat UC is clinically needed.

RESULTS

For this purpose, turmeric-derived nanoparticles with a specific population (TDNPs 2) were characterized, and their targeting ability and therapeutic effects against colitis were investigated systematically. The hydrodynamic size of TDNPs 2 was around 178 nm, and the zeta potential was negative (- 21.7 mV). Mass spectrometry identified TDNPs 2 containing high levels of lipids and proteins. Notably, curcumin, the bioactive constituent of turmeric, was evidenced in TDNPs 2. In lipopolysaccharide (LPS)-induced acute inflammation, TDNPs 2 showed excellent anti-inflammatory and antioxidant properties. In mice colitis models, we demonstrated that orally administrated of TDNPs 2 could ameliorate mice colitis and accelerate colitis resolution via regulating the expression of the pro-inflammatory cytokines, including TNF-α, IL-6, and IL-1β, and antioxidant gene, HO-1. Results obtained from transgenic mice with NF-κB-RE-Luc indicated that TDNPs 2-mediated inactivation of the NF-κB pathway might partially contribute to the protective effect of these particles against colitis.

CONCLUSION

Our results suggest that TDNPs 2 from edible turmeric represent a novel, natural colon-targeting therapeutics that may prevent colitis and promote wound repair in colitis while outperforming artificial nanoparticles in terms of low toxicity and ease of large-scale production.

N-Acetyldopamine Dimer Attenuates DSS-Induced Ulcerative Colitis by Suppressing NF-κB and MAPK Pathways

Ulcerative Colitis (UC) is a major form of chronic inflammatory bowel disease of the colonic mucosa and exhibits progressive morbidity. There is still a substantial need of small molecules with greater efficacy and safety for UC treatment. Here, we report a N-acetyldopamine dimer (NADD) elucidated (2R,3S)-2-(3′,4′-dihydroxyphenyl)-3-acetylamino-7-(N-acetyl-2″-aminoethyl)-1,4-benzodioxane, which is derived from traditional Chinese medicine Isaria cicadae, exhibits significant therapeutic efficacy against dextran sulfate sodium (DSS)-induced UC. Functionally, NADD treatment effectively relieves UC symptoms, including weight loss, colon length shortening, colonic tissue damage and expression of pro-inflammatory factors in pre-clinical models. Mechanistically, NADD treatment significantly inhibits the expression of genes in inflammation related NF-κB and MAPK signaling pathways by transcriptome analysis and western blot, which indicates that NADD inhibits the inflammation in UC might through these two pathways. Overall, this study identifies an effective small molecule for UC therapy.

Chitosan derivatives functionalized dual ROS-responsive nanocarriers to enhance synergistic oxidation-chemotherapy

The efficient triggering of prodrug release has become a challengeable task for stimuli-responsive nanomedicine utilized in cancer therapy due to the subtle differences between normal and tumor tissues and heterogeneity. In this work, a dual ROS-responsive nanocarriers with the ability to self-regulate the ROS level was constructed, which could gradually respond to the endogenous ROS to achieve effective, hierarchical and specific drug release in cancer cells. In brief, DOX was conjugated with MSNs via thioketal bonds and loaded with β-Lapachone. TPP modified chitosan was then coated to fabricate nanocarriers for mitochondria-specific delivery. The resultant nanocarriers respond to the endogenous ROS and release Lap specifically in cancer cells. Subsequently, the released Lap self-regulated the ROS level, resulting in the specific DOX release and mitochondrial damage in situ, enhancing synergistic oxidation-chemotherapy. The tumor inhibition Ratio was achieved to 78.49%. The multi-functional platform provides a novel remote drug delivery system in vivo.

All-In-One Biomimetic Nanoplatform Based on Hollow Polydopamine Nanoparticles for Synergistically Enhanced Radiotherapy of Colon Cancer

Even though radiotherapy is the most important therapeutic strategy for colon cancer treatment, there is an enormous demand to improve radiosensitivity in solid tumor destruction. For this purpose, a biomimetic nanoplatform based on hollow polydopamine nanoparticles (HP) with homologous targeting and pH-responsive drug release properties is designed. In this work, HP is constructed by using a chelation competition-induced polymerization strategy and then modified with the cancer cell membrane. Hollow polydopamine integrated with Pt nanoparticles (Pt@HP) has a catalase-like activity, which can be used to trigger endogenous H₂ O₂ into O₂ , relieving hypoxia of the tumor microenvironment (TME). With mesoporous shells and large cavities, Pt@HP shows efficient apoptin^100-109 (AP) and verteporfin (VP) loading to form AVPt@HP@M. Under X-ray irradiation, AVPt@HP@M exerts a radiosensitization effect via multiple strategies, including relieving hypoxia (Pt NPs), enhancing tumor apoptosis (AP), and X-ray-induced photodynamic therapy (X-PDT) (VP). Further metabonomics analysis shows that the specific mechanism of the AVPt@HP@M is through influencing purine metabolism. Without appreciable systemic toxicity, this nanoplatform highlights a new strategy for effective radiosensitization and provides a reference for treating malignant tumors.

All-in-one theranostic nano-platform based on polymer nanoparticles for BRET/FRET-initiated bioluminescence imaging and synergistically anti-inflammatory therapy for ulcerative colitis

BACKGROUND

Ulcerative colitis (UC), a subtype of inflammatory bowel disease (IBD), has evolved into a global burden given its high incidence. There is a clinical need to create better diagnostic and therapeutic approaches to UC.

RESULTS

We fabricated P-selectin binding peptide-decorated poly lactic-co-glycolic acid (PBP-PLGA-NP) doped with two lipophilic dyes, DiL and DiD. Meanwhile, two low-toxic anti-inflammatory natural products (betulinic acid [BA] and resveratrol [Res]) were co-loaded in the PBP-PLGA-NP system. The BA/Res-loaded NPs had an average size of around 164.18 nm with a negative zeta potential (- 25.46 mV). Entrapment efficiencies of BA and Res were 74.54% and 52.33%, respectively, and presented a sustained drug release profile. Further, the resulting PBP-PLGA-NP could be internalized by RAW 264.7 cells and Colon-26 cells efficiently in vitro and preferentially localized to the inflamed colon. When intravenously injected with luminol, MPO-dependent bioluminescence imaging to visualize tissue inflammation was activated by the bioluminescence and fluorescence resonance energy transfer (BRET-FRET) effect. Importantly, injected NPs could remarkably alleviate UC symptoms yet maintain intestinal microbiota homeostasis without inducing organ injuries in the mice models of colitis.

CONCLUSIONS

This theranostic nano-platform not only serves as a therapeutic system for UC but also as a non-invasive and highly-sensitive approach for accurately visualizing inflammation.

Physicochemical Characterization and Pharmacological Evaluation of Novel Propofol Micelles with Low-Lipid and Low-Free Propofol

We developed safe and stable mixed polymeric micelles with low lipids and free propofol for intravenous administration, to overcome the biological barrier of the reticuloendothelial system (RES), reduce pain upon injection, and complications of marketed propofol formulation. The propofol-mixed micelles were composed of distearoyl-phosphatidylethanolamine-methoxy-poly (ethylene glycol 2000) (DSPE mPEG2k) and Solutol HS 15 and were optimized using Box Behnken design (BBD). The optimized formulation was evaluated for globule size, zeta potential, loading content, encapsulation efficiency, pain on injection, histological evaluation, hemolysis test, in vivo anesthetic action, and pharmacokinetics, in comparison to the commercialized emulsion Diprivan. The optimized micelle formulation displayed homogenous particle sizes, and the free drug concentration in the micelles was 60.9% lower than that of Diprivan. The paw-lick study demonstrated that propofol-mixed micelles significantly reduced pain symptoms. The anesthetic action of the mixed micelles were similar with the Diprivan. Therefore, we conclude that the novel propofol-mixed micelle reduces injection-site pain and the risk of hyperlipidemia due to the low content of free propofol and low-lipid constituent. It may be a more promising clinical alternative for anesthetic.

Oral Delivery of Pterostilbene by L-Arginine-Mediated "Nano-Bomb" Carrier for the Treatment of Ulcerative Colitis

BACKGROUND

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) of unknown aetiology affecting the colon and rectum. Pterostilbene (PS) has been reported as an effective antioxidant and anti-inflammatory agent in preclinical IBD models. However, the therapeutic outcomes of PS are limited by potential side effects associated with the systemic exposure and the modest bioavailability afforded by its oral administration. These issues can be improved with the use of intelligent responsive nanoparticles with the ability of lysosome escape, given their high drug delivery capacity and reducing the side effects.

MATERIALS AND METHODS

Herein, the hyaluronic acid (HA)-modified L-arginine CO2 nanoparticles (HA-L-Arg-CO2@NPs) loaded with PS (HA-PS@NPs) are constructed. Under lysosomal pH conditions, HA-PS@NPs liberate CO2 and generate a pH-activated nano-bomb effect to augment the cytosolic delivery of PS.

RESULTS

HA-L-Arg-CO2@NPs show great biocompatibility and the excellent ability to target the colon. Using lipopolysaccharide-induced inflammation in vitro, the prominent anti-inflammatory effect of HA-L-Arg-CO2@NPs and HA-PS@NPs is observed. Further, orally administered HA-L-Arg-CO2@NPs and HA-PS@NPs via the colon-targeted chitosan/alginate (CA) hydrogel downregulate pro-inflammatory cytokines and reduce intestinal permeability, yielding significant outcomes in alleviating the symptoms of UC.

CONCLUSION

This pH-activated "nano-bomb" carrier with therapeutic effect can be exploited as efficient oral drug carriers for UC treatment.

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.

Reactive Oxygen Species-Responsive Polyether Micelle Nanomaterials for Targeted Treatment of Ulcerative Colitis

As one of the most challenging inflammatory diseases, the incidence of ulcerative colitis (UC) is increasing year by year, but the existing therapeutic drugs are not effective and lack of targeting. Nanomaterials are expected to become promising delivery system due to their good targeting effects. Here, we designed a nanomaterial sensitive to reactive oxygen species, which can be used to treat IBD, especially UC. It is a self-assembled polyether micelle that can be oxidized at the inflammation site where the concentration of reactive oxygen increases, and effectively release the encapsulated budesonide (Bud). Experiments have proved that for DSS-induced colitis, the synthetic drug-loaded nanoparticles have excellent therapeutic effects, can effectively repair intestinal barrier, and significantly improve the damaged colon tissue. At the same time, it has a beneficial regulatory effect on inflammatory factors. Molecular mechanism studies have shown that it achieves its therapeutic effects by activating the peroxisome proliferators-activated receptors-γ (PPAR-γ) pathway and inhibiting the nuclear factor (NF)-κB pathway. This study proves that oral nano-micelles have an important impact on improving the efficacy of UC treatment drugs and have far-reaching significance for the targeted treatment of gastrointestinal diseases.

Colonic Delivery of Celastrol-Loaded Layer-by-Layer Liposomes with Pectin/Trimethylated Chitosan Coating to Enhance Its Anti-Ulcerative Colitis Effects

Herein, a flexible oral colon-targeting delivery system, mediated by electrostatic layer-by-layer alternate deposition with pectin-trimethyl chitosan (TMC) onto liposomes-loading celastrol (Cel/PT-LbL Lipo), was fabricated to enhance anti-UC efficacy. Along with layer-by-layer coating, Cel/Lipo exhibited surface charge reversal, a slight increase in particle size, and a sustained drug release profile in a simulative gastrointestinal tract medium. Based on its bilayer coating of polysaccharides, Cel/PT-LbL Lipo alleviated cytotoxicity of celastrol in colon epithelial NCM460 cells. Due to the strong mucoadhesion of TMC with mucin, PT-LbL Lipo benefited colon localization and prolonged retention ability of its payloads. Ultimately, Cel/PT-LbL Lipo significantly mitigated colitis symptoms and accelerated colitis repair in DSS-treated mice by regulating the levels of pro-inflammatory factors related to the TLR4/MyD88/NF-κB signaling pathway. Collectively, this study demonstrates that the pectin/trimethylated chitosan coating may allow for Cel/PT-LbL Lipo to function as a more beneficial therapeutic strategy for UC treatment.

Oral Core-Shell Nanoparticles Embedded in Hydrogel Microspheres for the Efficient Site-Specific Delivery of Magnolol and Enhanced Antiulcerative Colitis Therapy

Although magnolol (Mag), an anti-inflammatory natural compound, has been demonstrated to play protective effects on ulcerative colitis (UC), its application as an alternative therapeutic reagent for UC treatment is still greatly impeded due to its poor stability in the gastrointestinal tract and insufficient accumulation in the inflamed colon lesion. Nano-/microsized drug delivery systems can potentially overcome some challenges regarding the oral administration of phytochemicals, which still confront premature early drug release, degradation of NPs, or the sustained drug release of MPs. In this study, we primarily loaded Mag into the core-shell zein-based nanoparticles with chondroitin sulfate coating (Mag@CS-Zein NPs) with an average size of 142.27 ± 5.11 nm, showing significant macrophage-targeting and enhanced colon epithelial cellular uptake capacity. Then, we embedded Mag@CS-Zein NPs into hydrogel microspheres via an electrospraying technology. The Mag@CS-Zein NPsinMPs presented a uniform-sized sphere with an average size of 164.36 ± 6.29 μm and sustained drug-release profiles. Compared to CS-Zein NPs, the developed CS-Zein NPsinMPs exhibited prolonged colon retention on the inflammatory surface, as seen from ex vivo and in vivo imaging fluorescence adhesion experiments. Based on the advantage of the combination of hybrid nanoparticles-in-microparticles, oral administration of Mag@CS-Zein NPsinMPs significantly alleviated colitis symptoms in DSS-treated mice by regulating the expression levels of proinflammatory cytokines (TNF-α, IL-6, and IL-1β) and anti-inflammatory cytokines (IL-10) and factor accelerated colonic mucosal barrier repair via upregulating the expression of ZO-1 and occludin. This study provides great insights into the oral drug delivery of natural compounds for UC therapy.

Venetoclax nanomedicine alleviates acute lung injury via increasing neutrophil apoptosis

Delayed neutrophil apoptosis has been proved to be closely associated with acute lung injury. A Bcl-2 inhibitor, venetoclax, can improve the clinical outcome of acute lung injury based on its pro-apoptotic effect. However, pulmonary delivery of free venetoclax is hindered by its water insolubility, which results in limited bioavailability and pharmacological effects. An amphipathic polymer-based nanodelivery system has been extensively used to improve the delivery of this insoluble drug and enhance its bioavailability. In this study, an amphiphilic poly(ethylene glycol) modified poly(α-lipoic acid) nanoparticle with an extended lung tissue-resident time was utilized to deliver venetoclax. Compared to free venetoclax, the nanoformulated venetoclax (Nf-venetoclax) presented better efficacy for acute lung injury through increasing neutrophil apoptosis in vivo. In addition, a stronger pro-apoptotic effect of Nf-venetoclax was also demonstrated in vitro. Our study provides encouraging evidence that Nf-venetoclax exhibits effective therapy for acute lung injury.