Functionalized lipid nanoparticles modulate the blood-brain barrier and eliminate α-synuclein to repair dopamine neurons

The challenge in the clinical treatment of Parkinson's disease lies in the lack of disease-modifying therapies that can halt or slow down the progression. Peptide drugs, such as exenatide (Exe), with potential disease-modifying efficacy, have difficulty in crossing the blood-brain barrier (BBB) due to their large molecular weight. Herein, we fabricate multi-functionalized lipid nanoparticles (LNP) Lpc-BoSA/CSO with BBB targeting, permeability-increasing and responsive release functions. Borneol is chemically bonded with stearic acid and, as one of the components of Lpc-BoSA/CSO, is used to increase BBB permeability. Immunofluorescence results of brain tissue of 15-month-old C57BL/6 mice show that Lpc-BoSA/CSO disperses across the BBB into brain parenchyma, and the amount is 4.21 times greater than that of conventional LNP. Motor symptoms of mice in Lpc-BoSA/CSO-Exe group are significantly improved, and the content of dopamine is 1.85 times (substantia nigra compacta) and 1.49 times (striatum) that of PD mice. α-Synuclein expression and Lewy bodies deposition are reduced to 51.85% and 44.72% of PD mice, respectively. Immunohistochemical mechanism studies show AKT expression in Lpc-BoSA/CSO-Exe is 4.23 times that of PD mice and GSK-3β expression is reduced to 18.41%. Lpc-BoSA/CSO-Exe could reduce the production of α-synuclein and Lewy bodies through AKT/GSK-3β pathway, and effectively prevent the progressive deterioration of Parkinson's disease. In summary, Lpc-BoSA/CSO-Exe increases the entry of exenatide into brain and promotes its clinical application for Parkinson's disease therapy.

Acyclovir-Loaded Solid Lipid Nanoparticles: A Permeation and Penetrability Study

Herpes simplex virus type I is a cutaneous infection treated with acyclovir. The topical treatment has therapeutic challenges due to the deficient delivery of the drug through epithelial barriers. This results in an inadequate drug-virus interaction in the basal epidermis (virus replication site). For this reason, it is essential to generate drug carrier systems that overcome these limitations. In this study, we evaluated the permeation (through in vitro test Franz cells) and penetration (by ex vivo test Tape Stripping) of a topical formulation of acyclovir loaded in solid lipid nanoparticles and a conventional formulation (Aciclor®). The acyclovir solid lipid nanoparticles were prepared using hot homogenization and sonication methods. The results yielded a particle size of 85 ± 2 nm, a polydispersity index of 0.24 ± 0.01, a zeta potential of −16 ± 2 mV, and 94% ± 3% of encapsulated drug. The in vitro test revealed that the permeability of acyclovir solid lipid nanoparticles formulation was superior compared to reference formulation, with values of 1473.74 ± 30.14 µg/cm2 for the solid lipid nanoparticles and 893.36 ± 38.09 µg/cm2 for the reference formulation. The ex vivo test demonstrated that acyclovir solid lipid nanoparticles exhibited superior penetrability through the stratum corneum compared to the reference formulation, with total amounts of 3767 µg for the solid lipid nanoparticles and 2162 µg for the reference formulation. These findings seem promising in advancing new effective therapies against herpes generated by herpes simplex virus type I.

Characteristics and Transdermal Drug Delivery of Triamcinolone-Acetonide-Acetate-Loaded Solid Lipid Nanoparticles Carbomer Gel

Aim To prepare triamcinolone-acetonide-acetate (TAA)-loaded solid lipidnanoparticles (SLN) carbomer gel with tripalmitin glyceride (TPG), and investigate theircharacteristics and transdermal drug delivery. Methods SLN suspension was prepared by high-pressurehomogenization technique, and then mixed with carbomer gel matrix to get SLN gel. The morphology,particle size with polydispersi-ty index (PI) and zeta potential were examined by atomic forcemicroscopy (AFM) and photon correlation spectroscopy (PCS). The entrapment efficiency, stability andin vitro drug release were also studied. The transdermal drug delivery through porcine ear skin wasevaluated using modified Franz diffusion cells. Results The SLN had a spherical shape with theaverage size of (95.5 - 186.2) nm, the zeta potential of (-26.3- -15.7) mV and the entrapmentefficiency of 67.4%-90.3% for different TAA encapsulated compounds. TAA-SLN carbomer gel had goodstability, the release profile in vitro fitted Higuchi equation. In comparison with conventionalhydrogels, TAA-SLN carbomer gel resulted in higher drug permeation amount and drug deposition withinporcine ear skin after 24 h penetration experiment. Conclusion TAA-SLN carbomer gel is preparedwith stable physicochemical properties. The release profile and improved drug permeation into skinmake it be a promising vehicle for transdermal drug delivery.

Targeting the resolution pathway of inflammation using Ac2–26 peptide-loaded PEGylated lipid nanoparticles for the remission of rheumatoid arthritis

Rheumatoid arthritis(RA)is a common autoimmune disease characterized by joint inflammation and immune dysfunction.Although various therapeutic approaches have been utilized for the treatment of RA in clinical applications,the low responsiveness of RA patients and undesired systemic toxicity are still unresolved problems.Targeting the resolution pathway of inflammation with pro-resolving mediators would evoke the protective actions of patient for combating the inflammation.Ac2–26,a 25-amino acid peptide derived from Annexin A(a pro-resolving mediator),has shown good efficacy in the treatment of inflammatory disorders.However,the low bioavailability of Ac2–26 peptides hinders their efficacy in vivo.In this paper,we formed PEGylated lipid nanoparticles(LDNPs)by the co-assembly of l-ascorbyl palmitate(L-AP)and N-(carbonyl methoxypolyethylene glycol-2000)-1,2-distearoyl-sn–glycero-3-phosphoethanolamine(DSPE-PEG 2 k)to encapsulate and deliver Ac2–26 peptides to the arthritic rats.They showed good stability and biocompatibility.After being intravenously administrated,Ac2–26 peptide-loaded PEGylated lipid nanoparticles(ADNPs)showed the prolonged in vivo circulation time and enhanced accumulation in inflamed sites.In vivo therapeutic evaluations revealed that ADNPs could attenuate synovial inflammation and improve joint pathology.Therefore,the pro-resolving therapeutic strategy using ADNPs is effective in RA treatment.

New research on development of solid lipid nanoparticles

To review the latest research development of the solid lipid nanoparticles(SLN) according to the recent relevant literatures.Each preparations of the SLN have advantages and disadvantages.Among the total preparations of the SLN.the high pressure homogenization(HPH) and the microemulsion tech- nique are to praise highly.The drug incorporation and release profiles could be modified as adjustment of production parameters.The SLNis an excellent drug delivery system and has broad prospects in the phar- maceutical field.

Efficacy of combined albendazol and praziquntel and their loaded solid lipid nanoparticles components in chemoprophylaxis of experimental hydatidosis

Objective:To evaluate the efficacy of combined ABZ and PZQ and their solid lipid nanoparticles in chemoprophylaxis of cystic echinococcosis(CE).Methods:ABZ and PZQ loaded solid lipid nanoparticles(SLNs) were prepared by high shear homogenization and microemulsion congealing techniques with some minor modification.Nanoparticles average size,polydispersity index(PDI),and particle size distribution were determined by scanning electron microscopy(SEM) and photon correlation spectroscopy.Forty females BALB/c were experimentally infected by protoscoleces(PSC) and randomly divided into four equal groups of 10 mice.After the end of the 3 months treatment period and 2 months rest,mice were sacrificed and the peritoneal cavity was opened for removal,counting,measuring,and histological analysis of hydatid cyst.Results:The results indicated that ABZ and PZQ chemoprophylaxis treatment reduced the wet weight and size of developed cysts 77.3% and 79%,respectively.The corresponding result for the ABZ and PZQ loaded SLNs was 83% and 85%,respectively.Conclusions:This study for the first time demonstrated that ABZ and PZQ loaded SLNs is superior to free ABZ and PZQ for the chemoprophylaxis of CE in mice.

Synthetic and nature-derived lipid nanoparticles for neural regeneration

Challenges and opportunities in nerve regeneration： The central nervous system （CNS） has a limited ability to regen- erate. Subsequent to spinal injury, glial scar formation, creat- ed by fibroblasts, neuroglia, monocytes, and endothelial cells, inhibits regeneration of the injured nerve. The peripheral nervous system （PNS） has a greater regeneration potential than the CNS; however, the current gold standard of treat- ment for a large nerve defect is still autologous nerve grafts, which require multiple surgeries. For this reason, researchers have been trying to regenerate nervous tissues, including brain, spinal cord. and PeriPheral nerves, for decades.

Monitoring the in vivo siRNA release from lipid nanoparticles based on the fluorescence resonance energy transfer principle

The siRNA-loaded lipid nanoparticles have attracted much attention due to its significant gene silencing effect and successful marketization.However,the in vivo distribution and release of siRNA still cannot be effectively monitored.In this study,based on the fluorescence resonance energy transfer(FRET)principle,a fluorescence dye Cy5-modified survivin siRNA was conjugated to nanogolds(Au-DR-siRNA),which were then wrapped with lipid nanoparticles(LNPs)for monitoring the release behaviour of siRNA in vivo.The results showed that once Au-DR-siRNA was released from the LNPs and cleaved by the Dicer enzyme to produce free siRNA in cells,the fluorescence of Cy5 would change from quenched state to activated state,showing the location and time of siRNA release.Besides,the LNPs showed a significant antitumor effect by silencing the survivin gene and a CT imaging function superior to iohexol by nanogolds.Therefore,this work provided not only an effective method for monitoring the pharmacokinetic behaviour of LNP-based siRNA,but also a siRNA delivery system for treating and diagnosing tumors.

Solid lipid nanoparticles loading adefovir dipivoxil for antiviral therapy

Herein,solid lipid nanoparticles(SLN)were proposed as a new drug delivery system for adefovir dipivoxil(ADV). The octadecylamine-fluorescein isothiocynate(ODA-FITC)was synthesized and used as a fluorescence maker to be incorporated into SLN to investigate the time-dependent cellular uptake of SLN by HepG2.2.15.The SLN of monostearin with ODA-FITC or ADV were prepared by solvent diffusion method in an aqueous system.About 15 wt%drug entrapment efficiency(EE)and 3 wt% drug loading(DL)could be reached in SLN loading ADV.Comparing with free ADV,the inhibitory effects of ADV loaded in SLN on hepatitis B surface antigen(HBsAg),hepatitis B e antigen(HBeAg)and hepatitis B virus(HBV)DNA levels in vitro were significantly enhanced.

Storage Stability of Alpha-Lipoic Acid-loaded Lipid Nanoparticles

Alpha-lipoic acid-loaded lipid nanoparticles(ALA-LNs) were prepared by high pressure homogenization method.The influences of storage conditions such as time and temperature on the physical and chemical storage stability of ALA-LNs were studied in details.The stability was evaluated by particle size and polydispersity index,morphology of ALA-LNs,and capacity of ALA loading.The dilution and pH stability of ALA-LNs suspensions were also studied.After three months storage,the mean size of ALA-LNs at 4 and 40 ℃ was increased by 2.68% and 3.62% compared with the original size,respectively.ALA-LNs stored at 40 ℃ had ellipsoid shape and the mean size was about 152 nm(SD=23.6).The loading capacity of ALA at 40 ℃ was much higher than those stored at other two temperatures.The good dilution and pH stability were also demonstrated.The sample had good fluidity even at 4 ℃.

Preparation, optimization, and characterization of chitosancoated solid lipid nanoparticles for ocular drug delivery

The present study aimed to develop and optimize chitosan coated solid lipid nanoparticles(chitosan-SLNs)encapsulated with methazolamide. Chitosan-SLNs were successfully prepared by a modified oil-in-water emulsification-solvent evaporation method with glyceryl monostearate as the solid lipid and phospholipid as the surfactant. Systematic screening of formulation factors was carried out. The optimized formula for preparation was screened by orthogonal design as well as Box-Behnken design with entrapment efficiency, particle size and zeta potential as the indexes. The entrapment efficiency of the optimized formulation(methazolamide-chitosan-SLNs)prepared was(58.5± 4.5)%,Particle size(247.7 ± 17.3) nm and zeta potential(33.5 ±3.9) mV. Transmission electron microscopy showed homogeneous spherical particles in the nanometer range. A prolonged methazolamide in vitro release profile was obtained in the optimized chitosan-SLNs suspension compared with methazolamide solution. No ocular damages were observed in the susceptibility test on albino rabbits. The results suggest that the combination of orthogonal design and Box-Behnken design is efficient and reliable in the optimization of nanocarriers, and chitosanSLNs is a potential carrier for ophthalmic administration.

Bovine Serum Albumin Loaded Solid Lipid Nanoparticles Prepared by Double Emulsion Method

Solid lipid nanoparticles loaded with bovine serum albumin（BSA） were prepared by a double emulsion method. As the mass fraction of the model drug BSA increased from 0 to 15%, the particle size gradually increased. The physical stability of the nanoparticles was investigated by zeta potential measurement and they were shown to be quite stable. Fluorescence spectroscopy confirmed that the loaded position of BSA was on the interface between the inner aqueous phase and the solid lipid phase. Both Fourier-transform infrared spectroscopy and circular dichroism spectra indicate that BSA in the nanoparticles was not destroyed, but the secondary structure was disrupted slightly.

Evaluation of atherosclerotic lesions in cholesterol-fed mice during treatment with paclitaxel in lipid nanoparticles： a magnetic resonance imaging study

Cholesterol-core nanoparticles （LDE） have been shown to be recognized by low-density lipoprotein receptors （LDLR） after administration; therefore, LDE is an ideal vehicle to deliver drug with targeting property. Paclitaxel, when incorporated into LDE, promotes atherosclerosis regression with reduced drug toxicity in rabbits through LDLR. Here, we tested whether LDE-paclitaxel could still be effective in reducing diet-induced atherosclerosis in a mouse model without LDLR. Nineteen LDLR knockout male mice were fed 1% cholesterol for 12 weeks. Then, 12 animals received 4-weekly intraperitoneal LDE-paclitaxel （4 mg/kg） while 7 controls received saline solution. On week 12 and 16, in vivo MR/of the aortic roots was performed. Aorta macroscopy was made after euthanasia. Reduction ofatherosclerotic lesions was observed. LDE-paclitaxel treatment resulted in reduction of wall area （14%） and stenosis （22%） by MR/and 33% by macroscopy. Thus, LDE-paclitaxel may produce pharmacological effects through LDE uptake by mechanisms other than LDLR.

β-Lactoglobulin stabilized lipid nanoparticles enhance oral absorption of insulin by slowing down lipolysis

Lipid-based nanocarriers have staged a remarkable comeback in the oral delivery of proteins and peptides, but delivery efficiency is compromised by lipolysis. β-Lactoglobulin(β-lg) stabilized lipid nanoparticles, including nanoemulsions(NE@β-lg) and nanocapsules(NC@β-lg), were developed to enhance the oral absorption of insulin by slowing down lipolysis due to the protection from β-lg. Cremophor EL stabilized nanoemulsions(NE@Cre-EL) were prepared and set as a control. The lipid nanoparticles produced mild and sustained hypoglycemic effects, amounting to oral bioavailability of 3.0% ± 0.3%, 7.0% ± 1.1%, and7.7% ± 0.8% for NE@Cre-EL, NE@β-lg, and NC@β-lg, respectively. Aggregation-caused quenching(ACQ)probes enabled the identification of intact nanoparticles, which were used to investigate the in vivo and intracellular fates of the lipid nanoparticles. In vitro digestion/lipolysis and ex vivo imaging confirmed delayed lipolysis from β-lg stabilized lipid nanoparticles. NC@β-lg was more resistant to intestinal lipolysis than NE@β-lg due to the Ca^(2+)-induced crosslinking. Live imaging revealed the transepithelial transport of intact nanoparticles and their accumulation in the liver. Cellular studies confirmed the uptake of intact nanoparticles. Slowing down lipolysis via food proteins represents a good strategy to enhance the oral absorption of lipid nanoparticles and thus co-formulated biomacromolecules.

M1-polarized macrophage-derived cellular nanovesicle-coated lipid nanoparticles for enhanced cancer treatment through hybridization of gene therapy and cancer immunotherapy

Optimum genetic delivery for modulating target genes to diseased tissue is a major obstacle for profitable gene therapy.Lipid nanoparticles(LNPs),considered a prospective vehicle for nucleic acid delivery,have demonstrated efficacy in human use during the COVID-19 pandemic.This study introduces a novel biomaterial-based platform,M1-polarized macrophage-derived cellular nanovesicle-coated LNPs(M1-C-LNPs),specifically engineered for a combined gene-immunotherapy approach against solid tumor.The dual-function system of M1-C-LNPs encapsulates Bcl2-targeting siRNA within LNPs and immune-modulating cytokines within M1 macrophage-derived cellular nanovesicles(M1-NVs),effectively facilitating apoptosis in cancer cells without impacting T and NK cells,which activate the intratumoral immune response to promote granule-mediating killing for solid tumor eradication.Enhanced retention within tumor was observed upon intratumoral administration of M1-C-LNPs,owing to the presence of adhesion molecules on M1-NVs,thereby contributing to superior tumor growth inhibition.These findings represent a promising strategy for the development of targeted and effective nanoparticle-based cancer genetic-immunotherapy,with significant implications for advancing biomaterial use in cancer therapeutics.

Scalable synthesis of lipid nanoparticles for nucleic acid drug delivery using an isometric channel-size enlarging strategy

Lipid nanoparticles(LNPs)have emerged as highly effective delivery systems for nucleic acid-based therapeutics.However,the broad clinical translation of LNP-based drugs is hampered by the lack of robust and scalable synthesis techniques that can consistently produce formulations from early development to clinical application.In this work,we proposed a method to achieve scalable synthesis of LNPs by scaling inertial microfluidic mixers isometrically in three dimensions.Moreover,a theoretical predictive method,which controls the mixing time to be equal across different chips,is developed to ensure consistent particle size and size distribution of the synthesized LNPs.LNPs loaded with small interfering RNA(siRNA)were synthesized at different flow rates,exhibiting consistent physical properties,including particle size,size distribution and encapsulation efficiency.This work provides a practical approach for scalable synthesis of LNPs consistently,offering the potential to accelerate the transition of nucleic acid drug development into clinical application.

Systematic development of ionizable lipid nanoparticles for placental mRNA delivery using a design of experiments approach

Ionizable lipid nanoparticles(LNPs)have gained attention as mRNA delivery platforms for vaccination against COVID-19 and for protein replacement therapies.LNPs enhance mRNA stability,circulation time,cellular uptake,and preferential delivery to specific tissues compared to mRNA with no carrier platform.However,LNPs are only in the beginning stages of development for safe and effective mRNA delivery to the placenta to treat placental dysfunction.Here,we develop LNPs that enable high levels of mRNA delivery to trophoblasts in vitro and to the placenta in vivo with no toxicity.We conducted a Design of Experiments to explore how LNP composition,including the type and molar ratio of each lipid component,drives trophoblast and placental delivery.Our data revealed that utilizing C12-200 as the ionizable lipid and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine(DOPE)as the phospholipid in the LNP design yields high transfection efficiency in vitro.Analysis of lipid molar composition as a design parameter in LNPs displayed a strong correlation between apparent pKa and poly(ethylene)glycol(PEG)content,as a reduction in PEG molar amount increases apparent pKa.Further,we present one LNP platform that exhibits the highest delivery of placental growth factor mRNA to the placenta in pregnant mice,resulting in synthesis and secretion of a potentially therapeutic protein.Lastly,our high-performing LNPs have no toxicity to both the pregnant mice and fetuses.Our results demonstrate the feasibility of LNPs as a platform for mRNA delivery to the placenta,and our top LNP formulations may provide a therapeutic platform to treat diseases that originate from placental dysfunction during pregnancy.

β-catenin mRNA encapsulated in SM-102 lipid nanoparticles enhances bone formation in a murine tibia fracture repair model

Fractures continue to be a global economic burden as there are currently no osteoanabolic drugs approved to accelerate fracture healing.In this study,we aimed to develop an osteoanabolic therapy which activates the Wnt/β-catenin pathway,a molecular driver of endochondral ossification.We hypothesize that using an mRNAbased therapeutic encodingβ-catenin could promote cartilage to bone transformation formation by activating the canonical Wnt signaling pathway in chondrocytes.To optimize a delivery platform built on recent advancements in liposomal technologies,two FDA-approved ionizable phospholipids,DLin-MC3-DMA(MC3)and SM-102,were used to fabricate unique ionizable lipid nanoparticle(LNP)formulations and then tested for transfection efficacy both in vitro and in a murine tibia fracture model.Using firefly luciferase mRNA as a reporter gene to track and quantify transfection,SM-102 LNPs showed enhanced transfection efficacy in vitro and prolonged transfection,minimal fracture interference and no localized inflammatory response in vivo over MC3 LNPs.The generatedβ-cateninGOF mRNA encapsulated in SM-102 LNPs(SM-102-β-cateninGOF mRNA)showed bioactivity in vitro through upregulation of downstream canonical Wnt genes,axin2 and runx2.When testing SM-102-β-cateninGOF mRNA therapeutic in a murine tibia fracture model,histomorphometric analysis showed increased bone and decreased cartilage composition with the 45μg concentration at 2 weeks post-fracture.μCT testing confirmed that SM-102-β-cateninGOF mRNA promoted bone formation in vivo,revealing significantly more bone volume over total volume in the 45μg group.Thus,we generated a novel mRNA-based therapeutic encoding aβ-catenin mRNA and optimized an SM-102-based LNP to maximize transfection efficacy with a localized delivery.

Engineering Cell-Selective Charge-Altering Lipid Nanoparticles for Efficient siRNA Delivery in Vivo

Lipid nanoparticles(LNPs)have emerged as a powerful platform for RNA delivery;the chemical engineering of LNP for efficient delivery of RNA into cytosol remains critical but challenging.One promising strategy is the use of permanently positively charged lipids,which have been shown to enhance the stability and delivery efficiency of LNPs.However,the resulting strong electrostatic interactions reduced the RNA release capacity from the lipoplexes.Herein,we engineered a hydrogen peroxide(H_(2)O_(2))-triggered charge-altering LNP(CALNP)for efficient small interfering RNA(siRNA)delivery and tumor therapy in mice.The incorporation of phenylboronic acid(PBA)into ionizable lipids generated permanently positively charged lipids.A CALNP with optimal lipid formulations was identified,exhibiting enhanced transfection efficiency with effective lysosomal escape through dual effects of electrostatic interaction and ligand-receptor binding.H_(2)O_(2)-triggered removal of PBA groups regenerated ionizable LNP with reduced positive charges at physiological pH,allowing cell-selective siRNA release in the cytoplasm.Our results demonstrated that CALNPs exhibited improved siRNA transfection and gene silencing efficiency.We also showed potent CALNP activity against the polo-like kinase 1(Plk1)gene by effectively silencing Plk1 mRNA and subsequent suppression of tumor growth.Collectively,these findings highlighted the potential of CALNP as an efficient platform for RNA delivery and tumor therapeutics.

Apatinib and gamabufotalin co-loaded lipid/Prussian blue nanoparticles for synergistic therapy to gastric cancer with metastasis

Due to the non-targeted release and low solubility of anti-gastric cancer agent,apatinib(Apa),a first-line drug with long-term usage in a high dosage often induces multi-drug resistance and causes serious side effects.In order to avoid these drawbacks,lipid-film-coated Prussian blue nanoparticles(PB NPs)with hyaluronan(HA)modification was used for Apa loading to improve its solubility and targeting ability.Furthermore,anti-tumor compound of gamabufotalin(CS-6)was selected as a partner of Apawith reducing dosage for combinational gastric therapy.Thus,HA-Apa-Lip@PB-CS-6 NPs were constructed to synchronously transport the two drugs into tumor tissue.In vitro assay indicated that HA-Apa-Lip@PB-CS-6 NPs can synergistically inhibit proliferation and invasion/metastasis of BGC-823 cells via downregulating vascular endothelial growth factor receptor(VEGFR)and matrix metalloproteinase-9(MMP-9).In vivo assay demonstrated strongest anti-tumor growth and liver metastasis of HA-Apa-Lip@PB-CS-6 NPs administration in BGC-823 cells-bearing mice compared with other groups due to the excellent penetration in tumor tissues and outstanding synergistic effects.In summary,we have successfully developed a new nanocomplexes for synchronous Apa/CS-6 delivery and synergistic gastric cancer(GC)therapy.