A novel preparative method for nanoparticle albumin-bound paclitaxel with high drug loading and its evaluation both in vitro and in vivo

Human serum albumin-bound paclitaxel nanoparticle inhibits cervical carcinoma cell proliferation and oxidative damage through CYP3A4 and CYP2C8

Background

Cervical cancer (CC) is currently the most common malignant tumour in the female reproductive tract, and paclitaxel (PTX) is a commonly used chemotherapeutic agent, but tumour cell resistance will seriously affect the therapeutic efficacy of PTX. Nanoparticle human serum albumin-bound paclitaxel (Nano-HSA-PTX) is a novel drug delivery modality that may have superior effects to PTX alone.

Objective

To clarify the effect of Nano-HSA-PTX on cervical carcinoma (CC) cells and the underlying mechanisms.

Methods

After the preparation of Nano-HSA-PTX, its morphology was observed by electron transmission microscope (TEM), and its entrapment efficiency (EE%) and drug loading rate (DL%) were detected. Nano-HSA-PTX was compared with conventional PTX for drug metabolism. Additionally, CC HeLa and SiHa cells were purchased and divided into three groups to treat with Nano-HSA-PTX, PTX and normal saline, respectively. MTT, cell cloning, Transwell and cell scratch assays were carried out to determine cell proliferation, invasion and migration, flow cytometry and Western blotting were performed to detect apoptosis rate and apoptosis-related protein expression, and PCR was conducted to quantify oxidative damage indicators. Further, CYP3A4 and CYP2C8 expression patterns in CC cells (HeLa and SiHa) and human normal cervical epithelia (End1/E6E7) and the changes of their levels under the intervention of Nano-HSA-PTX were measured. Subsequently, C57BL/6mice were purchased for subcutaneous tumorigenesis experiment to observe the impact of Nano-HSA-PTX on tumor growth.

Results

Under TEM, Nano-HSA-PTX was complete and arranged compactly, with a stable structure and markedly higher EE% and DL% than PTX (P < 0.05). Under Nano-HSA-PTX intervention, the proliferation, invasion, migration and oxidative damage of HeLa and SiHa were significantly decreased compared with the control and PTX groups, while the apoptosis was increased (P < 0.05). Besides, elevated CYP3A4 and CYP2C8 levels were observed in CC cells, which were inhibited by Nano-HSA-PTX and PTX (P < 0.05). Finally, tumorigenesis experiments in nude mice revealed that Nano-HSA-PTX could inhibit tumor growth.

Conclusion

Compared with PTX, Nano-HSA-PTX has a superior effect of inhibiting CC activity. And this mechanism of action was carried out by inhibiting the expression of CYP3A4 and CYP2C8.

The characteristics and biological activity enhancements of melatonin encapsulations for skin care product applications

Melatonin (MLT) exhibits antioxidant, ultraviolet protection, anti-inflammatory, and anti-aging properties. However, its effectiveness is limited by instability, a short half-life, and incompatible absorption. In this research, we encapsulated melatonin (MLT) in transfersomes (MT) and niosomes (MN) to enhance their properties and investigate their effects through in vitro cell assays using murine macrophages cells and human foreskin fibroblasts cells. The vesicle morphology, vesicle size, polydispersity index, zeta potential, entrapment efficiency (EE%), attenuated total reflectance-Fourier transform spectroscopy (ATR-FTIR) spectra, along with in vitro release, permeation profiles, and stability study were also evaluated. The results showed that both encapsulations displayed spherical morphology at the nanometric scale, their great physical stability and provided an EE% range of 58-78%. The MLT incorporation into the vesicle was confirmed by the ATR-FTIR spectra. Additionally, the encapsulation' release profiles fitted with the Higuchi model, indicating controlled release of melatonin. Furthermore, MT showed greater permeability than MN and MS including melatonin deposition. In cell assays, MT exhibited significantly higher nitric oxide inhibition and stimulation of collagen compared to MN and MS. Therefore, MT demonstrated the highest possibility for anti-inflammatory and collagen-stimulating activities that could be applied in pharmaceutical or anti-aging cosmetic products.

Human Serum Albumin Nanoparticles as a Carrier of 20(S)-Protopanaxadiol via Intramuscular Injection to Alleviate Cyclophosphamide-Induced Myelosuppression

Myelosuppression is a prevalent and potentially life-threatening side effect during chemotherapy. As the main active component of ginseng, 20(S)-protopanaxadiol (PPD) is capable of relieving myelosuppression by restoring hematopoiesis and immunity. In this study, PPD was encapsulated in human albumin nanoparticles (PPD-HSA NPs) by nanoparticle albumin-bound (Nab) technology for intramuscular injection to optimize its pharmacokinetic properties and promote recovery of myelosuppression. The prepared PPD-HSA NPs had a particle size of about 280 nm with a narrow size distribution. PPD dispersed as an amorphous state within the PPD-HSA NPs, and the NPs exhibited in vitro sustained release behavior. PPD-HSA NPs showed a favorable pharmacokinetic profile with high absolute bioavailability, probably due to the fact that NPs entered into the blood circulation via lymphatic circulation and were eliminated slowly. In vivo distribution experiments demonstrated that PPD-HSA NPs were mainly distributed in the liver and spleen, but a strong fluorescence signal was also found in the inguinal lymph node, indicating drug absorption via a lymph route. The myelosuppressive model was established using cyclophosphamide as the inducer. Pharmacodynamic studies confirmed that PPD-HSA NPs were effective in promoting the level of white blood cells. Moreover, the neutrophil and lymphocyte counts were significantly higher in the PPD-HSA NPs group compared with the control group. This preliminary investigation revealed that PPD-HSA NPs via intramuscular administration may be an effective intervention strategy to alleviate myelosuppression.

Nanomedicine Strategies for Targeting Tumor Stroma

The tumor stroma, or the microenvironment surrounding solid tumors, can significantly impact the effectiveness of cancer therapies. The tumor microenvironment is characterized by high interstitial pressure, a consequence of leaky vasculature, and dense stroma created by excessive deposition of various macromolecules such as collagen, fibronectin, and hyaluronic acid (HA). In addition, non-cancerous cells such as cancer-associated fibroblasts (CAFs) and the extracellular matrix (ECM) itself can promote tumor growth. In recent years, there has been increased interest in combining standard cancer treatments with stromal-targeting strategies or stromal modulators to improve therapeutic outcomes. Furthermore, the use of nanomedicine, which can improve the delivery and retention of drugs in the tumor, has been proposed to target the stroma. This review focuses on how different stromal components contribute to tumor progression and impede chemotherapeutic delivery. Additionally, this review highlights recent advancements in nanomedicine-based stromal modulation and discusses potential future directions for developing more effective stroma-targeted cancer therapies.

Development of Carvedilol-Loaded Albumin-Based Nanoparticles with Factorial Design to Optimize In Vitro and In Vivo Performance

Carvedilol, an anti-hypertensive medication commonly prescribed by healthcare providers, falls under the BCS class II category due to its low-solubility and high-permeability characteristics, resulting in limited dissolution and low absorption when taken orally. Herein, carvedilol was entrapped into bovine serum albumin (BSA)-based nanoparticles using the desolvation method to obtain a controlled release profile. Carvedilol-BSA nanoparticles were prepared and optimized using 3² factorial design. The nanoparticles were characterized for their particle size (Y₁), entrapment efficiency (Y₂), and time to release 50% of carvedilol (Y₃). The optimized formulation was assessed for its in vitro and in vivo performance by solid-state, microscopical, and pharmacokinetic evaluations. The factorial design showed that an increment of BSA concentration demonstrated a significant positive effect on Y₁ and Y₂ responses with a negative effect on Y₃ response. Meanwhile, the carvedilol percentage in BSA nanoparticles represented its obvious positive impact on both Y₁ and Y₃ responses, along with a negative impact on Y₂ response. The optimized nanoformulation entailed BSA at a concentration of 0.5%, whereas the carvedilol percentage was 6%. The DSC thermograms indicated the amorphization of carvedilol inside the nanoparticles, which confirmed its entrapment into the BSA structure. The plasma concentrations of carvedilol released were observable from optimized nanoparticles up to 72 h subsequent to their injection into rats, revealing their longer in vivo circulation time compared to pure carvedilol suspension. This study offers new insight into the significance of BSA-based nanoparticles in sustaining the release of carvedilol and presents a potential value-added in the remediation of hypertension.

A Novel Paclitaxel Derivative for Triple-Negative Breast Cancer Chemotherapy

Paclitaxel-triethylenetetramine hexaacetic acid conjugate (PTX-TTHA), a novel semi-synthetic taxane, is designed to improve the water solubility and cosolvent toxicity of paclitaxel in several aminopolycarboxylic acid groups. In this study, the in vitro and in vivo antitumor effects and mechanisms of PTX-TTHA against triple-negative breast cancer (TNBC) and its intravenous toxicity were evaluated. Results showed the water solubility of PTX-TTHA was greater than 5 mg/mL, which was about 7140-fold higher than that of paclitaxel (<0.7 µg/mL). PTX-TTHA (10-10⁵ nmol/L) could significantly inhibit breast cancer proliferation and induce apoptosis by stabilizing microtubules and arresting the cell cycle in the G2/M phase in vitro, with its therapeutic effect and mechanism similar to paclitaxel. However, when the MDA-MB-231 cell-derived xenograft (CDX) tumor model received PTX-TTHA (13.73 mg/kg) treatment once every 3 days for 21 days, the tumor inhibition rate was up to 77.32%. Furthermore, PTX-TTHA could inhibit tumor proliferation by downregulating Ki-67, and induce apoptosis by increasing pro-apoptotic proteins (Bax, cleaved caspase-3) and TdT-mediated dUTP nick end labeling (TUNEL) positive apoptotic cells, and reducing anti-apoptotic protein (Bcl-2). Moreover, PTX-TTHA demonstrated no sign of acute toxicity on vital organs, hematological, and biochemical parameters at the limit dose (138.6 mg/kg, i.v.). Our study indicated that PTX-TTHA showed better water solubility than paclitaxel, as well as comparable in vitro and in vivo antitumor activity in TNBC models. In addition, the antitumor mechanism of PTX-TTHA was related to microtubule regulation and apoptosis signaling pathway activation.

Lymphocyte Membrane- and 12p1-Dual-Functionalized Nanoparticles for Free HIV-1 Trapping and Precise siRNA Delivery into HIV-1-Infected Cells

Despite the success of small interfering RNA (siRNA) in clinical settings and its potential value in human immunodeficiency virus (HIV) therapy, the rapid clearance and absence of precise delivery to target cells still hinder the therapeutic effect of siRNA. Herein, a new system, which can escape immune recognition, has HIV-1 neutralizing capacity, and the ability to deliver siRNA specifically into HIV-1-infected cells, is constructed by functionalizing siRNA delivery lipid nanoparticles with the lymphocyte membrane and 12p1. The constructed system is shown to escape uptake by the mononuclear phagocyte system. The constructed system exhibits strong binding ability with gp120, thus displaying distinguished neutralizing breadth and potency. The constructed system neutralizes all tested HIV-1 pseudotyped viruses with a geometric mean 80% inhibitory concentration (IC80) of 29.75 µg mL^-1 and inhibits X4-tropic HIV-1 with an IC80 of 64.20 µg mL^-1 , and R5-tropic HIV-1 with an IC80 of 16.39 µg mL^-1 . The new system also specifically delivers siRNA into the cytoplasm of HIV-1-infected cells and exhibits evident gene silencing of tat and rev. Therefore, this new system can neutralize HIV-1 and deliver siRNA selectively into HIV-1-infected cells and may be a promising therapeutic candidate for the precise therapy of HIV.

Polysorbate 80-coated albumin nanoparticles to deliver paclitaxel into the brain to treat glioma

Aim: To develop stable paclitaxel (PTX)-loaded bovine serum albumin (BSA) nanoparticles (BSA-NPs-PTX) as drug-delivery vehicles for delivering paclitaxel into the brain to treat glioma. Methods: This study used PTX-loaded BSA NPs coated with polysorbate 80 (Ps 80) to enhance PTX concentration in the brain. Results: The low IC50 indicated that the fabricated BSA-NPs-PTX and BSA-NPs-PTX-Ps 80 showed significantly enhanced cytotoxicity. The pharmacokinetic and biodistribution analysis of BSA-NPs-PTX and BSA-NPs-PTX 80 showed comparable pharmacokinetic profiles but were significantly different compared with free PTX. Conclusion: BSA-NPs-PTX-Ps 80 exhibited higher plasma concentration-time curves, as compared with BSA-NPs-PTX and PTX. BSA-NPs-PTX and BSA-NPs-PTX-Ps 80 showed significantly improved PTX distribution in the frontal cortex, posterior brain and cerebellum.

Nanoformulations - Insights Towards Characterization Techniques

BACKGROUND

Drug-loaded novel nanoformulations are gaining importance due to their versatile properties compared to conventional pharmaceutical formulations. Nanomaterials, apart from their multifactorial benefits, have a wider scope in the prevention, treatment, and diagnosis of cancer. Understanding the chemistry of drug-loaded nano-formulations to elicit its behaviour both at molecular and systemic levels is critical in the present scenario. Drug-loaded nanoformulations are controlled by their size, shape, surface chemistry, and release behavior. The major pharmaceutical drug loaded nanocarriers reported for anticancer drug delivery for the treatment of various forms of cancers such as lung cancer, liver cancer, breast cancer, colon cancer, etc include nanoparticles, nanospheres, nanodispersions, nanocapsules, nanomicelles, cubosomes, nanoemulsions, liposomes and niosomes. The major objectives in designing anticancer drug-loaded nanoformulations are to manage the particle size/morphology correlating with the drug release to fulfil the specific objectives. Hence, nano characterizations are very critical both at in vitro and in vivo levels.

OBJECTIVE

The main objective of this review paper is to summarise the major characterization techniques used for the characterization of drug-loaded nanoformulations. Even though information on characterization techniques of various nano-formulations is available in the literature, it is scattered. The proposed review will provide a comprehensive understanding of nanocharacterization techniques.

CONCLUSION

To conclude, the proposed review will provide insights towards the different nano characterization techniques along with their recent updates, such as particle size, zeta potential, entrapment efficiency, in vitro release studies (chromatographic HPLC, HPTLC, and LC-MS/MS analysis), EPR analysis, X-ray diffraction analysis, thermal analysis, rheometric, morphological analysis etc. Additionally, the challenges encountered by the nano characterization techniques will also be discussed.

Albumin Binds Doxorubicin via Self−Assembling Dyes as Specific Polymolecular Ligands

Congo red (CR) type self–assembled ribbon–like structures (SRLS) were previously shown to interact with some proteins, including albumin. SRLS also complex with some drugs with a flat, ring–shaped structure with aromatic characteristics, intercalating them into their ribbon structure. The combination of interaction with proteins and drug binding by SRLS enables the use of such systems for immunotargeting. It is especially interesting in the case of chemotherapeutic agents. The present experiments aimed to show that the model carrier system composed of supramolecular albumin and Congo red efficiently binds doxorubicin (Dox) and that the drug can be released at reduced pH. The presented results come from the studies on such complexes differing in the molar ratio of CR to Dox. The following methods were used for the analysis: electrophoresis, dialysis, gel filtration, spectral analysis, and analysis of the size of the hydrodynamic radius using the dynamic light scattering method (DLS). The applied methods confirmed the formation of the CR–Dox complex, with large dimensions and changed properties compared with free CR. The presented results show that albumin binds both CR and its complex with Dox. Various CR–Dox molar ratios, 5:1, 2:1, and 1:1, were analyzed. The confirmation of the possibility of releasing the drug from the carriers thus formed was also obtained. The presented research is important due to the search for optimal solutions for the use of SRLS in drug immunotargeting, with particular emphasis on chemotherapeutic agents.

Macrophage membrane- and cRGD-functionalized thermosensitive liposomes combined with CPP to realize precise siRNA delivery into tumor cells

Despite the success of small interfering RNAs (siRNAs) in clinical settings, their fast clearance and poor delivery efficiency to target cells still hinder their therapeutic effect. Herein, a new treatment system was constructed by combining thermosensitive liposomes with the macrophage membrane, tumor-targeting cyclic Arg-Gly-Asp peptide, a cell-penetrating peptide, and thermotherapy. The constructed system was found to be thermosensitive and stable; the proteins were inherited from the macrophage membrane. This new system combined with thermotherapy displayed the least uptake by macrophages, the greatest uptake by HepG2 cells, the most obvious HepG2 cell apoptosis, and the strongest inhibition of Bcl-2 mRNA and Bcl-2 protein in HepG2 cells. Moreover, 24 h after system administration in tumor-bearing mice, the most prominent distribution of siRNA was observed in tumors, while almost no siRNA was found in other organs. The strongest inhibition of Bcl-2 mRNA, Bcl-2 protein, and tumors was found in mice that had received the proposed system. In summary, when using the constructed system both in vitro and in mice, less uptake by the reticuloendothelial system, greater accumulation in tumor cells, and improved therapeutic efficacy were observed. Therefore, this new system can deliver siRNA selectively and efficiently, and it is a promising therapeutic candidate for precise tumor-targeted therapy.

Stimuli-responsive nanomaterials for cancer treatment: boundaries, opportunities and applications

Small molecule drugs, including most chemotherapies, are rapidly degraded and/or eliminated from the body, which is why high doses of these drugs are necessary, potentially producing toxic effects. Several types of nanoparticles loaded with anti-cancer drugs have been designed to overcome the disadvantages of conventional therapies. Modified nanoparticles can circulate for a long time, thus improving the solubility and biodistribution of drugs. Furthermore, they also allow the controlled release of the payload once its target tissue has been reached. These mechanisms can reduce the exposure of healthy tissues to chemotherapeutics, since the drugs are only released in the presence of specific tumour stimuli. Overall, these properties can improve the effectiveness of treatments while reducing undesirable side effects. In this article, we review the recent advances in stimuli-responsive albumin, gold and magnetic nanostructures for controlled anti-cancer drug delivery. These nanostructures were designed to release drugs in response to different internal and external stimuli of the cellular environment, including pH, redox, light and magnetic fields. We also describe various examples of applications of these nanomaterials. Overall, we shed light on the properties, potential clinical translation and limitations of stimuli-responsive nanoparticles for cancer treatment.