Preparation and Formulation Optimization of Methotrexate-loaded Human Serum Albumin Nanoparticles Modified by Mannose.

BACKGROUND: Methotrexate (MTX) is the representative drug among the disease- modifying anti-rheumatic drugs. However, the conventional treatment with MTX showed many limitations and side effects. OBJECTIVE: To strengthen the targeting ability and circulation time of MTX in the treatment of rheumatoid arthritis, the present study focused on developing a novel drug delivery system of methotrexate-loaded human serum albumin nanoparticles (MTX-NPs) modified by mannose, which are referred to as MTX-M-NPs. METHODS: Firstly, mannose-derived carboxylic acid was synthesized and further modified on the surface of MTX-NPs to prepare MTX-M-NPs. The formulation of nanoparticles was optimized by the method of central composite design (CCD), with the drug lipid ratio, oil-aqueous ratio, and cholesterol or lecithin weight as the independent variables. The average particle size and encapsulation efficiency were the response variables. The response of different formulations was calculated, and the response surface diagram, contour diagram, and mathematical equation were used to relate the dependent and independent variables to predict the optimal formula ratio. The uptake of MTX-M-NPs by neutrophils was studied through confocal laser detection. Further, MTX-M-NPs were subjected to assessment of the pharmacokinetics profile after intravenous injection with Sprague-Dawley rats. RESULTS: This targeting drug delivery system was successfully developed. Results from Nuclear Magnetic Resonance and Fourier Transform Infrared Spectroscopy analysis can verify the successful preparation of this drug delivery system. Based on the optimized formula, MTX-M-NPs were prepared with a particle size of 188.17 ± 1.71 nm and an encapsulation rate of 95.55 ± 0.33%. MTX-M-NPs displayed significantly higher cellular uptake than MTX-NPs. The pharmacokinetic results showed that MTX-M-NPs could prolong the in vivo circulation time of MTX. CONCLUSION: This targeting drug delivery system laid a promising foundation for the treatment of RA.

Treatment of Rheumatoid Arthritis by Serum Albumin Nanoparticles Coated with Mannose to Target Neutrophils.

Rheumatoid arthritis (RA) is an angiogenic and chronic inflammatory disease. One of the most extensively used first-line drugs against RA is methotrexate (MTX), but it shows poor solubility, short in vivo circulation, and off-target binding, leading to strong toxicity. To overcome these shortcomings, the present study loaded MTX into nanoparticles of human serum albumin modified with mannose (MTX-M-NPs) to target the drug to neutrophils. MTX-M-NPs were prepared, and their uptake by neutrophils was studied using laser confocal microscopy and flow cytometry. A chick chorioallantoic membrane assay was used to assess their ability to inhibit angiogenesis. The pharmacokinetics and tissue distribution of MTX-M-NPs were investigated using fluorescence microscopy and high-performance liquid chromatography. Their pharmacodynamics was evaluated in a rat model with arthritis induced by collagen. Neutrophils took up MTX-M-NPs significantly better than the same nanoparticles (NPs) without mannose. MTX-M-NPs markedly suppressed angiogenesis in chick embryos, and the MTX circulation was significantly longer when it was delivered as MTX-M-NPs than as a free drug. MTX-M-NPs accumulated mainly in arthritic joints. The retention of NPs was promoted by mannose-derived coating in arthritic joints. Serum levels of inflammatory cytokines, joint swelling, and bone erosion were significantly decreased by MTX-M-NPs. In conclusion, these NPs can prolong the in vivo circulation of MTX and target it to the sites of inflammation in RA, reducing drug toxicity. MTX-M-NPs allow the drug to exert its intrinsic anti-inflammatory, antiangiogenic, and analgesic properties, making it a useful drug delivery system in RA.

Enhanced Therapeutic Effect of RGD-Modified Polymeric Micelles Loaded With Low-Dose Methotrexate and Nimesulide on Rheumatoid Arthritis.

Angiogenesis plays an essential role in the progression of rheumatoid arthritis (RA). RGD peptide shows high affinity and selectivity for integrin αvß3, which is one of the most extensively examined target of angiogenesis. Nimesulide could improve the anti-rheumatic profile of methotrexate. But the clinical application was limited due to water-insolubility of both methotrexate and nimesulide and lacking targeting ability. Therefore, this study aimed to design a targeted drug delivery system of micelles mediated by RGD plus the passive targeting of micelles to solve the application problems of methotrexate and nimesulide (M/N), and thus enhance their combined therapeutic effect on RA. Methods: RGD was conjugated with NHS-PEG-PLA to form RGD-PEG-PLA for the preparation of RGD-modified drug-loaded micelles (R-M/N-PMs). The size and zeta potential of micelles were measured by dynamic light scattering. Morphology was detected by transmission electron microscopy. The inhibition effect of R-M/N-PMs on angiogenesis was assessed by the chick chorioallantoic membrane assay. The real-time fluorescence imaging analysis was conducted to examine the in vivo distribution of the fluorescence-labeled R-M/N-PMs. Rats arthritis model induced by Freund's adjuvant was used to evaluate the in vivo anti-inflammatory efficacy of R-M/N-PMs. Results: The in vitro study indicated successful development of R-M/N-PMs. R-M/N-PMs could markedly suppress the angiogenesis of chick embryos. The fluorescence-labeled R-M/N-PMs mainly accumulated in arthritic joints. RGD enhanced the targeting ability of micelles and thus promoted retention of micelles in arthritic joints. Moreover, R-M/N-PMs significantly alleviated the joint swelling while reducing bone erosion and serum levels of inflammatory cytokines. It helped to recover the bone microstructure of arthritic rats. Conclusion: Our results confirmed that the targeted delivery of the combination of a low dose of methotrexate and nimesulide mediated by RGD-modified polymeric micelles could enhance the therapeutic effect on rheumatoid arthritis. These findings provide a promising potential for the clinical therapy of rheumatoid arthritis.

Bone-targeting drug delivery system of biomineral-binding liposomes loaded with icariin enhances the treatment for osteoporosis.

BACKGROUND: Osteoporosis is a bone-incapacitating malady and it is characterized by obvious bone mass loss and bone microarchitecture deterioration. Current treatments for osteoporosis have many limitations, including the non-obvious therapeutic effect and long-term safety issues. Icariin is a pharmacologically active flavonoid glycoside, which shows potential application in treatment of osteoporosis. But its clinical application is limited by the inherent disadvantages such as poor water solubility, first pass effect after oral administration, and low bioavailability. Moreover, due to lack of targeting ability, icariin cannot accumulate at the local diseased region to provide early protection from fractures. To solve the application problems of icariin and enhance its therapeutic effects on osteoporosis, this work aimed to design a targeting drug delivery system of biomineral-binding liposomes (BBL) mediated by pyrophosphate ions. RESULTS: Biomineral-binding liposomes enhanced the binding ability of liposomes with hydroxyapatite particles. It increased the serum level of alkaline phosphatase and reduced that of tartrate-resistant acid phosphatase 5b. Meanwhile, BBL increased the mechanical strength of femoral midshaft, preserving the trabecular bone microarchitecture. Moreover, BBL could initiate bone turnover/remodeling of rats with osteoporosis. CONCLUSIONS: This drug targeting delivery system of BBL loading with icariin showed more therapeutic advantages than the free icariin for the treatment of osteoporosis, which may be a kind of valid candidate in future osteoporosis therapy.

NEP1-40-modified human serum albumin nanoparticles enhance the therapeutic effect of methylprednisolone against spinal cord injury.

BACKGROUND: Frequent injection of high-dose methylprednisolone (MP) is used to treat spinal cord injury (SCI), but free MP is associated with various side effects and its water solubility is low, limiting potential dosing regimes and administration routes. Albumin-based nanoparticles, which can encapsulate therapeutic drugs and release cargo in a controlled pattern, show high biocompatibility and low toxicity. The Nogo protein, expressed on the surface of oligodendrocytes, can inhibit axonal growth by binding with the axonal Nogo receptor (NgR). Peptide NEP1-40, an NgR antagonist, can bind specifically to Nogo, significantly improving functional recovery and axon growth in the corticospinal tract. Therefore, we hypothesized that delivering MP within nanoparticles decorated with NEP1-40 could avoid the disadvantages of free MP and enhance its therapeutic efficacy against SCI. RESULTS: We used human serum albumin to prepare MP-loaded NPs (MP-NPs), to whose surface we conjugated NEP1-40 to form NEP1-40-MP-NPs. Transmission electron microscopy indicated successful formation of nanoparticles. NEP1-40-MP-NPs were taken up significantly better than MP-NPs by the Nogo-positive cell line RSC-96 and were associated with significantly higher Basso-Beattie-Bresnahan locomotor scores in rats recovering from SCI. Micro-computed tomography assay showed that NEP1-40-MP-NPs mitigated SCI-associated loss of bone mineral density and accelerated spinal cord repair. CONCLUSIONS: NEP1-40-MP-NPs can enhance the therapeutic effects of MP against SCI. This novel platform may also be useful for delivering other types of drugs.