Search

Small interfering RNA (siRNA) has a promising future in the treatment of ocular diseases due to its high efficiency, specificity, and low toxicity in inhibiting the expression of target genes and proteins. However, due to the unique anatomical structure of the eye and various barriers, delivering nucleic acids to the retina remains a significant challenge. In this study, we rationally design PACD, an A-B-C type non-viral vector copolymer composed of a hydrophilic PEG block (A), a siRNA binding block (B) and a pH-responsive block (C). PACDs can self-assemble into nanosized polymeric micelles that compact siRNAs into polyplexes through simple mixing. By evaluating its pH-responsive activity, gene silencing efficiency in retinal cells, intraocular distribution, and anti-angiogenesis therapy in a mouse model of hypoxia-induced angiogenesis, we demonstrate the efficiency and safety of PACD in delivering siRNA in the retina. We are surprised to discover that, the PACD/siRNA polyplexes exhibit remarkable intracellular endosomal escape efficiency, excellent gene silencing, and inhibit retinal angiogenesis. Our study provides design guidance for developing efficient nonviral ocular nucleic acid delivery systems. A rationally designed pH-responsive polymer PACD boosts robust cytosolic siRNA release in retinal cells and significantly inhibits retinal angiogenesis, providing design guidance for developing efficient nonviral ocular nucleic acid delivery systems. [Display omitted] [ABSTRACT FROM AUTHOR]

Immunotherapy has revolutionized the landscape of cancer treatment. However, single immunotherapy only works well in a small subset of patients. Combined immunotherapy with antitumor synergism holds considerable potential to boost the therapeutic outcome. Nevertheless, the synergistic, additive or antagonistic antitumor effects of combined immunotherapies have been rarely explored. Herein, we established a novel combined cancer treatment modality by synergizing p21-activated kinase 4 (PAK4) silencing with immunogenic phototherapy in engineered extracellular vesicles (EVs) that were fabricated by coating M1 macrophage-derived EVs on the surface of the nano-complex cores assembled with siRNA against PAK4 and a photoactivatable polyethyleneimine. The engineered EVs induced potent PAK4 silencing and robust immunogenic phototherapy, thus contributing to effective antitumor effects in vitro and in vivo. Moreover, the antitumor synergism of the combined treatment was quantitatively determined by the CompuSyn method. The combination index (CI) and isobologram results confirmed that there was an antitumor synergism for the combined treatment. Furthermore, the dose reduction index (DRI) showed favorable dose reduction, revealing lower toxicity and higher biocompatibility of the engineered EVs. Collectively, the study presents a synergistically potentiated cancer treatment modality by combining PAK4 silencing with immunogenic phototherapy in engineered EVs, which is promising for boosting the therapeutic outcome of cancer immunotherapy. The engineered extracellular vesicles (TPCS@EV) synergized potent p21-activated kinase 4 (PAK4) silencing and robust immunogenic phototherapy in vitro and in vivo , thus contributing to synergistically boosted antitumor therapeutic outcomes. [Display omitted] [ABSTRACT FROM AUTHOR]

Theoretically, siRNA has the ability to target any gene of interest, potentially addressing disease targets that are 'undruggable' for small molecules and proteins. Currently, there are six siRNA therapeutics that have been approved for clinical use, and approximately 20 additional candidates have progressed to late stages of clinical investigation. Targeted accumulation and cellular uptake (entry), endolysosomal escape (escape), and in vivo pharmaceutical performance (efficacy) (three 'E' challenges) are the most critical bottlenecks in siRNA drug development. Ligand-conjugated siRNAs are promising platforms that have made a breakthrough in robust extrahepatic delivery. Sophisticated and appropriate chemical modification may bring astounding breakthroughs in the stability and long-term efficacy of siRNA modalities. siRNA therapeutics have gained extensive attention, and to date six siRNAs are approved for clinical use. Despite being investigated for the treatment of metabolic, cardiovascular, infectious, and rare genetic diseases, cancer, and central nervous system (CNS) disorders, there exist several druggability challenges. Here, we provide insightful discussions concerning these challenges, comprising targeted accumulation and cellular uptake ('entry'), endolysosomal escape ('escape'), and in vivo pharmaceutical performance ('efficacy') – the three 'E' challenges – while also shedding light on siRNA drug development. Moreover, we propose several promising strategies that hold great potential in facilitating the clinical translation of siRNA therapeutics, including the exploration of diverse ligand-siRNA conjugates, expansion of potential disease targets, and excavation of novel modification geometries, as well as the development of combination therapies. [ABSTRACT FROM AUTHOR]

Novel 3-D floor-like ordered mesoporous carbon functionalized graphene composites, FLOMC-GO, with high graphitized carbon contents were successfully synthesized using a soft template method. The one-pot sol-gel method was employed to prepare the silica soft template. Then, the sandwich-like composites were further combined together to form a 3-D structure through pre-carbonization and carbonization. During these procedures, the sulphonyl and sulfide bridges were formed by cross-linking processes to connect the phenyl rings. The prepared FLOMC-GO was confirmed to have a large pore volume (1.03 cm 3 g −1 ), high BET surface area (544.99 m 2 g −1 ) and well-ordered mesoporous structure with a narrow pore-size concentrated at 3.74 nm. The content of carbon reached 80% and was highly graphitized. By taking advantage of the interactions between carbon and glycans, FLOMC-GO was utilized to enrich N-linked glycans from OVA and human serum. As expected, excellent size-exclusion was found during the enrichment of N-glycans released from OVA, and 25 N-linked glycans were identified. The intensity of glycans enriched by FLOMC-GO was 7 times to the result of active carbon, while the ratio of OVA digestion to BSA interfering proteins increased to 1:50. Additionally, 31 N-linked glycans in total were enriched from human serum. The relatively easy synthesis as well as ability to enrich N-linked glycans with high selectivity and efficiency makes FLOMC-GO a promising adsorbent material for the discovery of human serum biomarkers for disease diagnosis. [ABSTRACT FROM AUTHOR]

Population aging is an increasingly aggravated public issue worldwide. Nanomaterials with enzyme-like activities are recognized as potentially important nanomedicines, yet how to leverage their in vivo performance for anti-aging therapy is still challenging. Here inspired by vital roles of mitochondrial respiratory chain complex enzymes on bioenergy generation and longevity, we reported a Pd based single-atom nanozyme (Pd@PPy/GO) as cascade nanoreactors to improve mitochondrial activities for aging attenuation. By mimicking NADH oxidase (NOX) and Cytochrome c oxidase (CcO), the nanozyme can catalyze the cascade reactions on mitochondrial respiratory chain and produce NAD+ without any external stimuli. At both Caenorhabditis elegans (C. elegans) and cell levels, we verified that nanozyme treatment could boost the mitochondrial function and abundance. More importantly, the nanozyme showed excellent anti-aging and neuroprotective effect. Mechanically, the activated mitochondrial unfolded protein response (UPRmt) pathway plays a vital role in its anti-aging effect. Together, this work paves a way for nanocatalytic anti-aging therapy by rationally designing a simple and powerful nanozymes with dual-enzymatic activities. [Display omitted] • This work rationally designs the nanozyme mimicking dual mitochondrial enzymes. • Pd@PPy/GO nanozyme treatment boosts the mitochondrial function and abundance. • Pd@PPy/GO nanozyme shows excellent anti-aging and neuroprotective effect. • 2D Pd@PPy/GO is available to serve as an all-in-one anti-aging therapy platform. [ABSTRACT FROM AUTHOR]

DNA-based nanostructures have shown curative potential in drug delivery and anti-tumor therapy. However, the applications of such systems are limited by the lack of precise control over the space and duration of drug release. Here, we report a near-infrared (NIR) light-guided DNA nanodevice that enables controlled drug release for precise tumor imaging and therapy. The DNA nanodevice is constructed by engineering GC-rich DNA duplexes with an ultraviolet (UV) light labile moiety and further modification onto the surface of upconversion nanoparticles (UCNPs). The chemotherapeutic drug (doxorubicin, Dox) is intercalated into the GC motif of DNA duplexes, where the fluorescence signal of Dox is markedly quenched. Upon NIR light irradiation, the UCNPs acting as energy transducers emit UV light that can break the photolabile moiety in DNA duplexes, resulting in the controlled release of Dox and recovery of their fluorescence signal. We present that this DNA nanodevice is not only able to selectively induce tumor cells apoptosis via NIR light-mediated activation, but also enables in situ imaging and monitoring of drug release. Therefore, this modular strategy opens a window for remotely controlled drug delivery. [Display omitted] ● We reported a near-infrared (NIR) light-controlled DNA nanodevice for spatiotemporally controlled drug release. ● The NIR light-responsive system could efficiently image tumor cells and inhibit tumor cells proliferation. ● This strategy opens a door for precise control of drug delivery, which may offer a route for tumor imaging and therapy. [ABSTRACT FROM AUTHOR]

Abstract: Long circulation, cell internalization, endosomal escape and small interfering RNA (siRNA) release to the cytoplasm are the prerequisite considerations for siRNA delivery vectors. Herein, a kind of sheddable nanoparticles (NPs) with micelle architecture for siRNA delivery were fabricated by using an intracellular-activated polycation-detachable copolymer (PECssD), which was prepared by introducing highly reducing environment-responsive disulfide linkages between PEGylated polycaprolactone (PCL) and the grafted polycation, poly(2-dimethylaminoethyl methacrylate) (PDMAEMA). The architecture of PECssD self-assembled NPs includes a biodegradable hydrophobic PCL core, a PEG shield and a detachable comb-like polycation surface. The stable nanosized complexes of PECssD NPs with siRNA, termed PECssD/siRNA micelleplexes, were formed, which could prolong circulation, improve accumulation and retention in tumor tissue, and be favorable for internalization. In particular, the cleavage of the disulfide linkages in the intracellular microenvironment and the subsequent dissociation of the PDMAEMA/siRNA polyplexes from the PEGylated PCL cores of PECssD/siRNA micelleplexes were also confirmed, which facilitated the endosomal escape and the efficient release of siRNA. As a result, the distribution of siRNA in cytoplasm was enhanced and subsequently promoted the efficiency of siRNA in gene silencing. Furthermore, systemic administration of the NPs carrying siPlk1 (polo-like kinase 1 specific siRNA) induced a tumor-suppressing effect in the HeLa-Luc xenograft murine model. Therefore, the devised strategy of the polycation-detachable copolymer PECssD NPs could address the requirements of the multistep systemic delivery process of siRNA. The hydrophobic core of the PECssD/siRNA micelleplexes is expected to entrap antitumor drugs or other therapeutic agents for combined therapies. [Copyright &y& Elsevier]

Abstract: Small interfering RNA (siRNA) has a huge potential for the treatment or prevention of various diseases. However, to realize the therapeutic potential of siRNA drugs, efficient, tissue-specific and safe delivery technologies must be developed. Here we synthesized two kinds of polymers (PEGylated poly(2-aminoethyl methacrylate) labeled as PEG-b-PAEM or PEA, and guanidinylated PEGylated poly(2-aminoethyl methacrylate) marked as PEG-b-PAEM-co-PGEM or PEAG) using atom transfer radical polymerization and evaluated their capability of mediating siRNA delivery in vitro and in vivo. Both polymers presented excellent siRNA encapsulation ability, formed regular nanostructures with siRNA, robustly mediated cellular internalization and cytoplasmic localization of siRNA, and resulted in targeted gene knockdown efficiently. However, PEAG showed much more outstanding abilities referring to above evaluating indicators compared with PEA. Both PEA/siRNA and PEAG/siRNA polyplexes displayed strong liver, lung and spleen accumulation in mice for a long time after intravenous administration. PEAG/siApoB polyplexes (single dose at 1 mg/kg) further repressed ApoB expression in liver and resulted in block of lipid transportation. In addition, both polymers delivered high amounts of siRNA into tumor tissue in the Hela-Luc xenograft murine model. More siRNA accumulated in tumor with the increase of N/P ratio and PEAG/siRNA polyplexes showed higher siRNA accumulation than PEA/siRNA polyplexes at the same N/P ratio. These findings set the stage for further studies of structural–functional mechanisms and developments of siRNA therapeutics. [Copyright &y& Elsevier]

Abstract: Small interfering RNA (siRNA) is a powerful gene silencing tool and has promising prospects in basic research and the development of therapeutic reagents. However, the lack of an effective and safe tool for siRNA delivery hampers its application. Here, we introduced binary and ternary complexes that effectively mediated siRNA-targeted gene silencing. Both complexes showed excellent siRNA loading even at the low N/P/C ratio of 3:1:0. FACS and confocal microscopy demonstrated that nearly all cells robustly internalized siRNAs into the cytoplasm, where RNA interference (RNAi) occurred. Luciferase assay and Western blot verified that silencing efficacy reached >80%, and introducing folate onto the ternary complexes further enhanced silencing efficacy by about 10% over those without folate at the same N/P/C ratio. In addition, the coating of PGA-g-mPEG decreased the zeta potential almost to electroneutrality, and the MTT assay showed decreased cytotoxicity. In vivo distribution measurement and histochemical analysis executed in C57BL/6 and Hela tumor-bearing BALB/c nude mice showed that complexes accumulated in the liver, lungs, pancreas and tumors and were released slowly for a long time after intravenous injection. Furthermore, ternary complexes showed higher siRNA fluorescence intensity than binary complexes at the same N/P ratio in tumor tissues, those with folate delivered more siRNAs to tumors than those without folate, and more folate induced more siRNA transport to tumors. In addition, in vivo functional study showed that both binary and ternary complexes mediated down-regulation of ApoB in liver efficiently and consequently blocked the secretion of fatty acids into the blood, resulted in lipid accumulation in liver, liver steatosis and hepatic dysfunction. In conclusion, these complexes provided a powerful means of administration for siRNA-mediated treatment of liver-related diseases and various cancers, especial for pancreatic and cervical cancer. [Copyright &y& Elsevier]

Abstract: The multiformity in polymer structure and conformation design provides a great potential in improving the gene silencing efficiency of siRNA by polymer vectors. In order to provide information on the polymer design for siRNA delivery, the structural contributions of blocked or grafted poly(2-dimethylaminoethyl methacrylate) on PEGylated polycaprolactone nanoparticles (NPs) in siRNA delivery were studied. Herein, two kinds of self-assembly nanoparticles (NPs) formed by amphiphilic cationic polymers, methoxy poly(ethylene glycol)-block-polycaprolactone-block-poly(2-dimethylaminoethyl methacrylate) (mPEG-PCL-b-PDMAEMA, PECbD) and methoxy poly(ethylene glycol)-block-(polycaprolactone-graft-poly(2-dimethylaminoethyl methacrylate)) (mPEG-PCL-g-PDMAEMA, PECgD), were used to deliver siRNA for in vitro and in vivo studies. The physiochemical properties including size and zeta potential of PECbD NPs/siRNA and PECgD NPs/siRNA complexes were characterized. In vitro cytotoxicity, cellular uptake and siRNA knockdown efficiency were evaluated in HeLa-Luc cells. The endosome escape and intracellular distribution of PECbD NPs/siRNA and PECgD NPs/siRNA in HeLa-Luc cells were also observed. In vivo polymer mediated siRNA delivery and the complexes distribution in isolated organs were studied using mice and tumor-bearing mice. At the same total degree of polymerization (DP) of DMAEMA, PECgD NPs/siRNA complexes possessed higher zeta potentials than PECbD NPs/siRNA complexes (at the same N/P ratio), which may be the reason that PECgD NPs/siRNA complexes can deliver more siRNA into the cytoplasm and lead to higher in vitro luciferase and lamin A/C silencing efficiency than PECbD NPs/siRNA complexes. The in vivo imaging measurement and histochemical analysis also confirmed that siRNA could be delivered to lungs, livers, pancreas and HeLa-Luc tumors more efficiently by PECgD NPs than PECbD NPs. Meanwhile, the PDMAEMA chains of PECgD could be shortened which provides benefits for clearing. Therefore, PECgD NPs have great potential to be used as efficient non-viral carriers for in vivo siRNA delivery. [Copyright &y& Elsevier]

Abstract: Binary complexes of cationic polymers and DNA were used commonly for DNA delivery, whereas, the excess cationic charge of the binary complexes mainly leads to high toxicity and unstability in vivo. In this paper, ternary complexes by coating polyglutamic acid-graft-poly(ethylene glycol)(PGA-g-mPEG) onto binary complexes of polycaprolactone-graft-poly(N,N-dimethylaminoethyl methacrylate) (PCL-g-PDMAEMA) nanoparticles (NPs)/DNA were firstly developed for effective and targeted gene delivery. The coating of PGA-g-mPEG was able to decrease the zeta potential of the nano-sized DNA complexes nearly to electroneutrality without interferring with DNA condensation ability. As a result, the stability, the escape ability from endosomes and the transfection efficiency of the complexes were enhanced. The ternary complexes of PCL-g-PDMAEMA NPs/DNA/PGA-g-mPEG demonstrated lower cytotoxicity in CCK-8 measurements and higher gene transfection efficiency than the binary complexes in vitro. In addition, Lactate dehydrogenase (LDH) assay was performed to quantify the membrane-damaging effects of the complexes, which is consistent with the conclusion of CCK-8 measurement for cytotoxicity assay. The in vivo imaging measurement and histochemical analysis of tumor sessions confirmed that the intravenous administration of the ternary complexes with red fluorescent protein (RFP) as payload led to protein expression in tumor, which was further enhanced by the targeted coating of PGA-g-PEG-folate. [Copyright &y& Elsevier]

Abstract: A group of amphiphilic cationic polymers, methoxy polyethylene glycol-block-(polycaprolactone-graft-poly(2-(dimethylamino)ethyl methacrylate)) (PECD), were synthesized by combining ring-opening polymerization (ROP) and atom transfer radical polymerization (ATRP) methods to form nanoparticles (NPs). The structures of these amphiphilic cationic polymers were characterized by 1H NMR measurement. The PECD NPs have hydrophobic cores covered with hydrophilic PEG and cationic PDMAEMA chains. These self-assembly nanoparticles were characterized by dynamic light scattering (DLS) technique. PECD NPs can effectively condense DNA to form compact complexes of the size 65–160 nm suitable for gene delivery. The in vitro gene transfection studies of HeLa and HepG2 cells show that PECD NPs have better transfection efficiency compared to polyethylenimine (PEI) and Lipofectamine 2000 at low dose (N/P = 5). The cytotoxicity result shows that PECD NPs/DNA complexes at the optimal N/P ratio for transfection have comparable toxicity with PEI and Lipofectamine. These results indicate that PECD NPs have a great potential to be used as efficient polymeric carriers for gene transfection. [ABSTRACT FROM AUTHOR]

• siRNA therapy shows encouraging potential in disease treatment, but is hampered by insufficient delivery. • Combination of electroporation and microneedle constitutes a promising strategy, but it is quite challenging. • Rolling microneedle electrode array (RoMEA) was engineered by employing microfabrication technology in this study. • Efficiency restoration of immune surveillance and tumor killing were achieved by RoMEA-electroporated anti-PD-L1 siRNA. • RoMEA exhibited excellent safety profiles in vivo. Topical administration of siRNA, a clinically approved promising therapeutic modality, represents a much more transformative approach for drug development, compared to intravenous injection. To implement an efficient and extensive siRNA therapy in vivo , we engineered a rolling microneedle electrode array (RoMEA), which utilizes parallel circular blades with microneedle arrays on edge as electrodes. RoMEA integrates close-spaced microneedle electrodes and rolling structure to allow low-damage and large-area siRNA transfection. Upon applying RoMEA, regular micropores were established, efficient siRNA delivery and gene silence were achieved. In addition, employments of siRNA targeting programmed death-ligand 1 (PD-L1) alone, or combined with anti-programmed death-1 (PD-1) antibody or immunoadjuvant of CpG2395, in two tumor xenograft murine models demonstrated that proposed strategies restored efficient T cell immune response, conferring significant tumor growth inhibition with excellent safety profiles. RoMEA constitutes an unprecedented and ingenious clinic solution to large-area local delivery of nucleic acid for cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Exosomes have emerged as appealing candidate therapeutic agents and delivery nanoplatforms due to their endogenous features and unique biological properties. However, obstacles such as low isolation yield, considerable complexity and potential safety concerns, and inefficient drug payload substantially hamper their therapeutic applicability. To this end, developing bioinspired exosome-like nanoparticles has become a promising area to overcome certain limitations of their natural counterparts. Synthetically fabrication of exosome-like nanoparticles that harbor only crucial components of exosomes through controllable protocols strongly increases the pharmaceutical acceptability of these vesicles. Assembly of exosome-like nanovesicles derived from producer cells allows for a promising strategy for scale-up production. To improve the loading capability and delivery efficiency of exosomes, hybrid exosome-like nanovesicles and membrane-camouflaged nanoparticles towards better bridging synthetic nanocarriers with natural exosomes could be designed. Building off these observations, herein, efforts are made to give an overview of bioinspired exosome-like therapeutics and delivery nanoplatforms. We briefly recapitulate the recent advance in exosome biology with focus on tailoring exosomes as therapeutics and delivery vehicles. Furthermore, we elaborately discuss the biomimicry methodologies for preparation of exosome-like nanoparticles with special emphasis on offering insights into strategies for rational design of exosome-like biomaterials as effective and safe therapeutics and delivery nanoplatforms. Image 105638 [ABSTRACT FROM AUTHOR]

The emitter clogging is the most common hardware failure of nano-electrospray ionization, to improve the durability and electrospray stability of fused silica emitters, we demonstrate a means of fabricating nano-electrospray emitters with controllable aperture size and gradually-narrowed channel on the tip. We simulated the fluid morphologies in the emitter channels by computational fluid dynamics and found more stable flow on aperture-controllable nano-electrospray emitter. Besides, we found the unstable flow sections of commercial emitters match the actual clogging sections very well, indicating the main cause of emitter clogging is unstable flow. We further tested the emitters by nano-LC-MS based proteome analysis. Compared with the commercial emitter, aperture-controllable nano-electrospray emitters promoted the total ion chromatogram intensity by 25%, the number of identified proteins by 6.58%, and the number of identified peptides by 7.87%. In total, 989 proteins were identified from 1 μg of extracted mouse cardiac proteins. After the optimization by using mouse samples, we analyzed clinical auricular dextral tissues from patients undergoing cardiac surgery and found 16 proteins related to atrial fibrillation. Overall, aperture-controllable nano-electrospray emitter exhibits better sensitivity and reproducibility in the application of nano-LC-MS cardiac proteome analysis. Image 1 • An aperture-controllable nano-electrospray emitter has been successfully fabricated. • Fabricated emitters exhibit controllable aperture size and gradually-narrowed channel with stable flow on the tip. • The emitters could promote the total ion chromatogram intensity and proteins and peptides IDs in nano-LC-MS analysis. • Fabricated emitters exhibit better sensitivity and reproducibility in the cardiac proteome analysis. [ABSTRACT FROM AUTHOR]

Since its outbreak in late 2019, the novel coronavirus disease 2019 (COVID-19) has spread to every continent on the planet. The global pandemic has affected human health and socioeconomic status around the world. At first, the global response to the pandemic was to isolate afflicted individuals to prevent the virus from spreading, while vaccine development was ongoing. The genome sequence was first presented in early January 2020, and the phase I clinical trial of the vaccine started in March 2020 in the United States using novel lipid-based nanoparticle (LNP), encapsulated with mRNA termed as mRNA-1273. Till now, various mRNA-based vaccines are in development, while one mRNA-based vaccine got market approval from US-FDA for the prevention of COVID-19. Previously, mRNA-based vaccines were thought to be difficult to develop, but the current development is a significant accomplishment. However, widespread production and global availability of mRNA-based vaccinations to combat the COVID-19 pandemic remains a major challenge, especially when the mutations continually occur on the virus (e.g., the recent outbreaks of Omicron variant). This review elaborately discusses the COVID-19 pandemic, the biology of SARS-CoV-2 and the progress of mRNA-based vaccines. Moreover, the review also highlighted a detailed description of mRNA delivery technologies and the application potential in controlling other life-threatening diseases. Therefore, it provides a comprehensive view and multidisciplinary insights into mRNA therapy for broader audiences. [Display omitted] [ABSTRACT FROM AUTHOR]

• RNA-seq was used to systemically analyze diameter-dependent effects of MWCNTs. • Smaller MWCNTs more significantly induced cytotoxicity, lipid accumulation and ROS. • Smaller MWCNTs more potently altered genes related with cytotoxicity and lipids. • Less retention of smaller MWCNTs is probably due to MWCNT exocytosis. • MWCNT-induced lipid accumulation is related with PPARγ signalling pathway activation. Exposure to multi-walled carbon nanotubes (MWCNTs) might induce lipid droplet (LD) biogenesis, but the roles of physicochemical properties of MWCNTs, as well as the mechanisms, remain poorly understood. In this study, we investigated lipid laden foam formation in THP-1 macrophages exposed to MWCNTs of different diameters, and attempted transcriptomic analysis to study the possible mechanisms. We observed diameter-dependent cytotoxicity, lipid accumulation and intracellular reactive oxygen species production that were more pronounced for MWCNTs with smaller diameters compared with those with larger diameters. However, more MWCNTs with larger diameters were retained in macrophages after 24 h exposure. One possible explanation for the inverse relationship between MWCNT bio-effects and internalization is that macrophages altered the expression of exocytotic genes to export toxic MWCNTs. Transcriptomic data showed that MWCNTs with smaller diameters more effectively altered the expression of genes related with cytotoxicity and lipid metabolism, and KEGG pathway analysis suggested that MWCNTs with smaller diameters activated peroxisome proliferator-activated receptor (PPAR) signalling pathway (map03320), leading to over-expression of perilipin 2, the surface proteins of LDs. Western blot confirmed that MWCNTs effectively promoted CD36, PPARγ and perilipin 2, key components in map03320. Moreover, inhibition of PPARγ by chemicals or siRNA significantly inhibited lipid accumulation induced by MWCNTs with smaller diameters, and perilipin 2 proteins in MWCNT-exposed macrophages could be decreased by PPARγ siRNA. In conclusion, the results of this study revealed the induction of LDs by MWCNTs in a diameter-dependent manner through the activation of PPAR signalling pathway. [ABSTRACT FROM AUTHOR]

Recently, United States Food and Drug Administration (FDA) and European Commission (EC) approved Alnylam Pharmaceuticals' RNA interference (RNAi) therapeutic, ONPATTRO™ (Patisiran), for the treatment of the polyneuropathy of hereditary transthyretin-mediated (hATTR) amyloidosis in adults. This is the first RNAi therapeutic all over the world, as well as the first FDA-approved treatment for this indication. As a milestone event in RNAi pharmaceutical industry, it means, for the first time, people have broken through all development processes for RNAi drugs from research to clinic. With this achievement, RNAi approval may soar in the coming years. In this paper, we introduce the basic information of ONPATTRO and the properties of RNAi and nucleic acid therapeutics, update the clinical and preclinical development activities, review its complicated development history, summarize the key technologies of RNAi at early stage, and discuss the latest advances in delivery and modification technologies. It provides a comprehensive view and biotechnological insights of RNAi therapy for the broader audiences. [ABSTRACT FROM AUTHOR]

[Display omitted] Timely and accurate assessment and diagnosis are extremely important and beneficial for all diseases, especially for some of the major human disease, such as cancers, cardiovascular diseases, infectious diseases, and neurodegenerative diseases. Limited by the variable disease microenvironment, early imperceptible symptoms, complex immune system interactions, and delayed clinical phenotypes, disease diagnosis and treatment are difficult in most cases. Molecular imaging (MI) techniques can track therapeutic drugs and disease sites in vivo and in vitro in a non-invasive, real-time and visible strategies. Comprehensive visual imaging and quantitative analysis based on different levels can help to clarify the disease process, pathogenesis, drug pharmacokinetics, and further evaluate the therapeutic effects. This review summarizes the application of different MI techniques in the diagnosis and treatment of these major human diseases. It is hoped to shed a light on the development of related technologies and fields. [ABSTRACT FROM AUTHOR]

By its unique advantages over traditional medicine, nanomedicine has offered new strategies for cancer treatment. In particular, the development of drug delivery strategies has focused on nanoscale particles to improve bioavailability. However, many of these nanoparticles are unable to overcome tumor resistance to chemotherapeutic agents. Recently, new opportunities for drug delivery have been provided by oligonucleotides that can self-assemble into three-dimensional nanostructures. In this work, we have designed and developed functional DNA nanostructures to deliver the chemotherapy drug doxorubicin (Dox) to resistant cancer cells. These nanostructures have two components. The first component is a DNA aptamer, which forms a dimeric G-quadruplex nanostructure to target cancer cells by binding with nucleolin. The second component is double-stranded DNA (dsDNA), which is rich in -GC- base pairs that can be applied for Dox delivery. We demonstrated that Dox was able to efficiently intercalate into dsDNA and this intercalation did not affect the aptamer's three-dimensional structure. In addition, the Aptamer-dsDNA (ApS) nanoparticle showed good stability and protected the dsDNA from degradation in bovine serum. More importantly, the ApS&Dox nanoparticle efficiently reversed the resistance of human breast cancer cells to Dox. The mechanism circumventing doxorubicin resistance by ApS&Dox nanoparticles may be predominantly by cell cycle arrest in S phase, effectively increased cell uptake and decreased cell efflux of doxorubicin. Furthermore, the ApS&Dox nanoparticles could effectively inhibit tumor growth, while less cardiotoxicity was observed. Overall, this functional DNA nanostructure provides new insights into the design of nanocarriers to overcome multidrug resistance through targeted drug delivery. [ABSTRACT FROM AUTHOR]

Due to their biodegradable character, polyesters such as polycaprolactone (PCL), poly( d , l -lactide) (PDLLA), and polylactic-co-glycolic acid (PLGA) were widely used as the hydrophobic cores of amphiphilic cationic nanoparticles (NPs) for siRNA delivery. However, fewer researches focused on facilitating siRNA delivery by adjusting the polyester composition of these nanoparticles. Herein, we investigated the contribution of polyester segments in siRNA delivery in vitro by introducing different ratio of DLLA moieties in PCL segments of mPEG-block-PCL-graft-poly(dimethylamino ethyl methacrylate)(PEG-b-PCL-g-PDMAEMA). It was noticed that compared with the other ratios of DLLA moieties, a certain molar ratio (about 70%) of the NPs, named mPEG 45 -P(CL 21 -co-DLLA 48 )-g-(PDMAEMA 29 ) 2 (PECLD-70), showed the highest gene knockdown efficiency but poorest cellular uptake ability in vitro. Further research revealed that NPs with various compositions of the polyester cores showed different physicochemical properties including particle size, zeta potential and stiffness, leading to different endocytosis mechanisms thus influencing the cellular uptake efficiency. Subsequently, we observed that the cells treated by PECLD-70 NPs/Cy5 siRNA complexes exhibited more diffuse Cy5 signal distribution than other NPs by confocal laser scanning microscope, which suggested that siRNA delivered by PECLD-70 NPs/Cy5 siRNA complexes possessed of stronger capabilities in escaping from endosome/lysosome, entering the RNA-induced silencing complex (RISC) and cutting the target mRNA efficiently. The different siRNA release profile was dominated by the degradation rate of polyester segments. Therefore, it could be concluded that the adjustment of hydrophobic core of cationic nanoparticles could significantly affect their transfection behavior and appropriate polyester composition should be concerned in designing of analogous siRNA vectors. [ABSTRACT FROM AUTHOR]

Optimal combination of hydrophobic-hydrophilic balance, proton buffering and electrostatic interaction is the key issue for designing polycations as efficient gene vectors and antibacterial agents. Herein, we screened a series of pH-sensitive quaternary ammonium-based amphiphilic triblock copolymers, mPEG 2k -P(DPA a /DMA b)-PQA c (TDDE-x), which had different pKa values and proton buffering capacities. Significantly, we found that both the highest siRNA intracellular delivery efficiency and the strongest antibacterial capacity occurred on TDDE-3 micelles with the segment structure of mPEG 2k -P(DPA 50 /DMA 56)-PQA 55. The TDDE-3/siRNA complex achieved 67% silencing efficiency on H9C2 cells (N/P = 5, 50 nM siRNA), higher than the advanced commercial transfection reagents RNAiMAX (58%) and Lipo2000 (30%). Moreover, TDDE-3 micelles showed quite low MICs of 32 μg/mL and 8 μg/mL against E. coli and S. aureus , respectively. Further studies on the structure-function relationship indicated that TDDE-3 micelles could mediate robust endosome escape and siRNA cytosolic release, and strong bacterial cell membrane-destabilizing function. Undoubtedly, this work reveals the possibility for double optimization of siRNA intracellular delivery efficiency and antibacterial activity of amphiphilic polycations by reasonable structure design, which is significant for low-cost development and clinical translation of efficient multifunctional polycations. [Display omitted] • Optimizing both of the siRNA intracellular delivery and antibacterial activity. • Strong proton buffering capacity in early endosome enhances siRNA endosome escape. • Robust gene silencing efficiency on H9C2 cells was obtained. • PEGylated polycation micelles can possess strong intrinsic antibacterial activity. [ABSTRACT FROM AUTHOR]

Cationic liposome based siRNA delivery system has improved the efficiencies of siRNA. However, cationic liposomes are prone to be rapidly cleared by the reticuloendothelial system (RES). Although modification of cationic liposomes with polyethylene glycol (PEG) could prolong circulation lifetime, PEG significantly inhibits siRNA entrapment efficiency, cellular uptake and endosomal/lysosomal escape process, resulting in low gene silencing efficiency of siRNA. In this study, we report the synthesis of zwitterionic polycarboxybetaine (PCB) based distearoyl phosphoethanolamine-polycarboxybetaine (DSPE-PCB) lipid for cationic liposome modification. The DSPE-PCB20 cationic liposome/siRNA complexes (lipoplexes) show an excellent stability in serum medium. The siRNA encapsulation efficiency of DSPE-PCB20 lipoplexes could reach 92% at N/P ratio of 20/1, but only 73% for DSPE-PEG lipoplexes. The zeta potential of DSPE-PCB20 lipoplexes is 8.19±0.53mV at pH 7.4, and increases to 24.6±0.87mV when the pH value is decreased to 4.5, which promotes the endosomal/lysosomal escape of siRNA. The DSPE-PCB20 modification could enhance the silencing efficiency of siRNA by approximately 20% over the DSPE-PEG 2000 lipoplexes at the same N/P ratio in vitro. Furthermore, DSPE-PCB20 lipoplexes could efficiently mediate the down-regulation of Apolipoprotein B (ApoB) mRNA in the liver and consequently decrease the total cholesterol in the serum in vivo, suggesting therapeutic potentials for siRNA delivery in hypercholesterolemia-related diseases. [ABSTRACT FROM AUTHOR]

We evaluated the in vivo efficacy of structurally flexible, cationic PAMAM dendrimers as a small interfering RNA (siRNA) delivery system in a Rag2-/-γc-/- (RAG-hu) humanized mouse model for HIV-1 infection. HIV-infected humanized Rag2-/-γc-/- mice (RAG-hu) were injected intravenously (i.v.) with dendrimer-siRNA nanoparticles consisting of a cocktail of dicer substrate siRNAs (dsiRNAs) targeting both viral and cellular transcripts. We report in this study that the dendrimer-dsiRNA treatment suppressed HIV-1 infection by several orders of magnitude and protected against viral induced CD4+ T-cell depletion. We also demonstrated that follow-up injections of the dendrimer-cocktailed dsiRNAs following viral rebound resulted in complete inhibition of HIV-1 titers. Biodistribution studies demonstrate that the dendrimer-dsiRNAs preferentially accumulate in peripheral blood mononuclear cells (PBMCs) and liver and do not exhibit any discernable toxicity. These data demonstrate for the first time efficacious combinatorial delivery of anti-host and -viral siRNAs for HIV-1 treatment in vivo. The dendrimer delivery approach therefore represents a promising method for systemic delivery of combinations of siRNAs for treatment of HIV-1 infection. [ABSTRACT FROM AUTHOR]

A variety of therapies have been developed and used for the treatment of colon cancer, however, the high mortality rate remains high and more effective strategies are still in urgent needs. In this study, an immunotherapy approach that is composed of innate immune activator Astragaloside III (As) and the photodynamic therapy (PDT) reagent chlorine e6 (Ce6) ((As + Ce6)@MSNs-PEG), was developed for colon cancer treatment. We showed that (As + Ce6)@MSNs-PEG could effectively activate NK cells and inhibit the proliferation of tumor cells in vitro. It could also effectively reach tumor sites, induce infiltration of immune cells into the tumor, and enhance the cytotoxicity of natural killer cells and CD8+ T cells in vivo. Without obvious side effects, (As + Ce6)@MSNs-PEG treatment significantly inhibited tumor growth and extended the lifespan of tumor-bearing mice. Further results revealed that treatment of (As + Ce6)@MSNs-PEG led to enhanced IFN secretion by immune cells and increased T-box transcription factor (T-bet), which is highly expressed by T cells. Therefore, (As + Ce6)@MSNs-PEG may serve as an effective and safe platform for combinatory use with nano-herb medicine and PDT to provide a new therapy for colon cancer treatment. [ABSTRACT FROM AUTHOR]

Atherosclerosis, as a silent killer, remains one of the most common causes of human morbidity and mortality worldwide due to the lack of efficient strategy for early detection and targeted therapy. In this work, a self-driven bioinspired nanovehicle is developed, which can accurately manage early atherosclerosis with simultaneously multiple-targeting, dual-modality therapy as well as noninvasive magnetic resonance imaging (MRI). The magnetic nanoclusters (MNCs) with satisfactory superparamagnetism are camouflaged with leukocyte membranes, thus acquiring inherently targeting and transmigrating capabilities to intimal foam cells in early atherosclerotic lesions, which is validated using tailor-made microfluidic devices and transwell assays. Upon sequentially embedding an anti-inflammatory drug simvastatin (ST) and decorating a targetable apolipoprotein A-I mimetic 4F peptide (AP), the as-fabricated MNC@M-ST/AP exhibits excellent anti-atherosclerotic effects by alleviating inflammation and oxidative stress as well as promoting cholesterol efflux via RCT pathways. This bioinspired leukocyte membrane-hitchhiking strategy will open new perspectives for the future clinical translations of biocompatible nanosystem in early detection and treatment of atherosclerosis. [ABSTRACT FROM AUTHOR]

Messenger RNA (mRNA)-based therapeutics hold the potential to cause a major revolution in the pharmaceutical industry because they can be used for precise and individualized therapy, and enable patients to produce therapeutic proteins in their own bodies without struggling with the comprehensive manufacturing issues associated with recombinant proteins. Compared with the current therapeutics, the production of mRNA is much cost-effective, faster and more flexible because it can be easily produced by in vitro transcription, and the process is independent of mRNA sequence. Moreover, mRNA vaccines allow people to develop personalized medications based on sequencing results and/or personalized conditions rapidly. Along with the great potential from bench to bedside, technical obstacles facing mRNA pharmaceuticals are also obvious. The stability, immunogenicity, translation efficiency, and delivery are all pivotal issues need to be addressed. In the recently published research results, these issues are gradually being overcome by state-of-the-art development technologies. In this review, we describe the structural properties and modification technologies of mRNA, summarize the latest advances in developing mRNA delivery systems, review the preclinical and clinical applications, and put forward our views on the prospect and challenges of developing mRNA into a new class of drug. [ABSTRACT FROM AUTHOR]