Study on intralymphatic-targeted hyaluronic acid-modified nanoliposome: Influence of formulation factors on the lymphatic targeting

Hyaluronic Acid-Coated Nanoliposomes as Delivery Systems for Fisetin: Stability, Membrane Fluidity, and Bioavailability

Fisetin has shown numerous health benefits, whereas its food application is constrained by water insolubility, poor stability, and low bioaccessibility. This work investigated the potential of hyaluronic acid (HA)-coated nanoliposomes for the encapsulation and delivery of fisetin. It was observed that HA can adsorb onto the liposomal membrane through hydrogen bonding and maintain the spherical shape of nanoliposomes. Fluorescence analysis suggested that the HA coating restricted the motion and freedom of phospholipid molecules in the headgroup region and reduced the interior micropolarity of the nanoliposomes but did not affect the fluidity of the hydrophobic core. These effects were more pronounced for the HA with a low molecular weight (35 kDa) and moderate concentration (0.4%). The HA coating improved the storage and thermal stability of the nanoliposomes, as well as the digestive stability and bioaccessibility of the encapsulated fisetin. These findings could guide the development of HA-coated nanoliposomes for the controlled delivery of hydrophobic bioactives such as fisetin in functional foods.

Hyaluronic acid-modified liposomes Potentiated in-vivo anti-hepatocellular carcinoma of icaritin

Introduction: Icaritin (ICT), a promising anti-hepatocellular carcinoma (HCC) prenylated flavonoid, is hindered from being applied due to its low water solubility and high lipophilicity in poorly differentiated HCC which is associated with upregulation of CD44 isoforms. Thus, hyaluronic acid (HA), a natural polysaccharide with high binding ability to CD44 receptors, was used to formulate a modified liposome as a novel targeted ICT-delivery system for HCC treatment. Methods: The ICT-Liposomes (Lip-ICT) with and without HA were prepared by a combined method of thin-film dispersion and post-insertion. The particle size, polydispersity (PDI), zeta potential, encapsulation efficacy (%EE), drug loading content (%DLC), and in vitro drug release profiles were investigated for physicochemical properties, whereas MTT assay was used to assess cytotoxic effects on HCC cells, HepG2, and Huh7 cells. Tumor bearing nude mice were used to evaluate the inhibitory effect of HA-Lip-ICT and Lip-ICT in vivo. Results: Lip-ICT and HA-Lip-ICT had an average particle size of 171.2 ± 1.2 nm and 208.0 ± 3.2 nm, with a zeta potential of -13.9 ± 0.83 and -24.8 ± 0.36, respectively. The PDI resulted from Lip-ICT and HA-Lip-ICT was 0.28 ± 0.02 and 0.26 ± 0.02, respectively. HA-Lip-ICT demonstrated higher in vitro drug release when pH was dropped from 7.4 to 5.5, The 12-h release rate of ICT from liposomes increased from 30% at pH7.4 to more than 60% at pH5.5. HA-Lip-ICT displayed higher toxicity than Lip-ICT in both HCC cells, especially Huh7with an IC50 of 34.15 ± 2.11 μM. The in vivo tissue distribution and anti-tumor experiments carried on tumor bearing nude mice indicated that HA-Lip- ICT exhibited higher tumor accumulation and achieved a tumor growth inhibition rate of 63.4%. Discussion: The nano-sized Lip-ICT was able to prolong the drug release time and showed long-term killing HCC cells ability. Following conjugation with HA, HA-Lip-ICT exhibited higher cytotoxicity, stronger tumor targeting, and tumor suppression abilities than Lip-ICT attributed to HA-CD44 ligand-receptor interaction, increasing the potential of ICT to treat HCC.

Formulation, development and evaluation of hyaluronic acid-conjugated liposomal nanoparticles loaded with regorafenib and curcumin and their in vitro evaluation on colorectal cancer cell lines

Colorectal cancer is one of the major causes of global cancer, with chemotherapy and radiation therapy being effective but limited due to low specificity. Regorafenib, a multikinase inhibitor, provides hope to patients with metastatic colorectal cancer and was approved by the FDA in 2012. However, due to resistance issues and adverse events, its efficacy is compromised, necessitating further refinement. Meanwhile, curcumin, a compound of turmeric, exhibits anticancer effects through antioxidant and anti-inflammatory actions, induction of the apoptosis, arrest of cell cycle, inhibition of angiogenesis, and modulation of signaling pathways. Unfortunately, its clinical utility is limited by its poor bioavailability, pointing towards innovative drug delivery strategies for enhanced efficacy in colorectal cancer treatment. Hyaluronic acid (HA)-decorated liposomes (LIPO) have been developed to target colorectal cells through an overexpressed CD44 receptor, increasing antitumor and antimetastasis efficacy. This study investigates the possibility of loading curcumin (CUR) or regorafenib (REGO) into a liposomal formulation for passive and HA-actively targeted treatment, evaluating its critical quality attributes (CQA) (size, zeta potential, polydispersity index) and cytotoxic activity in the HT29 colorectal cancer cell line. The average particle size of the plain liposomes and those decorated with HA was 144.00 ± 0.78 nm and 140.77 ± 1.64 nm, respectively. In contrast, curcumin-loaded plain liposomes and HA-decorated liposomes had 140 ± 2.46 nm and 164.53 ± 15.13 nm, respectively. The prepared liposomes had a spherical shape with a narrow size distribution and an acceptable zeta potential of less than -30 mV. The encapsulation efficiency was 99.2 % ± 0.3 and 99.9 ± 0.2 % for HA-decorated and bare regorafenib loaded. The % EE was 98.9 ± 0.2 % and 97.5 ± 0.2 % for bare liposomal nanoparticles loaded with curcumin and coated with curcumin. The IC50 of free REGO, CUR, REGO-LIPO, CUR-LIPO, REGO-LIPO-HA and CUR-LIPO-HA were 20.17 ± 0.78, 64.4 ± 0.33, 224.8 ± 0.06, 49.66 ± 0.22, 73.66 ± 0.6, and 27.86 ± 0.49 µM, respectively. The MTT assay in HT29 cells showed significant cytotoxic activity of the HA-decorated liposomal formulation compared to the base uncoated formulation, indicating that hyaluronic acid-targeted liposomes loaded with regorafenib or curcumin could be a promising targeted formulation against colorectal cancer cells.

Hyaluronic Acid in Rheumatology

Hyaluronic acid (HA), also known as hyaluronan, is an anionic glycosaminoglycan widely distributed throughout various tissues of the human body. It stands out from other glycosaminoglycans as it lacks sulfation and can attain considerable size: the average human synovial HA molecule weighs about 7 million Dalton (Da), equivalent to roughly 20,000 disaccharide monomers; although some sources report a lower range of 3-4 million Da. In recent years, HA has garnered significant attention in the field of rheumatology due to its involvement in joint lubrication, cartilage maintenance, and modulation of inflammatory and/or immune responses. This review aims to provide a comprehensive overview of HA's involvement in rheumatology, covering its physiology, pharmacology, therapeutic applications, and potential future directions for enhancing patient outcomes. Nevertheless, the use of HA therapy in rheumatology remains controversial with conflicting evidence regarding its efficacy and safety. In conclusion, HA represents a promising therapeutic option to improve joint function and alleviate inflammation and pain.

Effective Attenuation of Arteriosclerosis Following Lymphatic-Targeted Delivery of Hyaluronic Acid-Decorated Rapamycin Liposomes

Background

The activation of lymphatic vessel function is the crux to resolving atherosclerosis (AS), a chronic inflammatory disease. Rapamycin (RAPA) recently has attracted considerable attention as a potent drug to induce atherosclerotic plaque attenuation. The objective of this work was to develop a ligand-decorated, RAPA-loaded liposome for lymphatic-targeted delivery of drugs to improve abnormal lymphatic structure and function, resulting in highly effective regression of atherosclerotic plaques.

Methods

Hyaluronic acid-decorated, RAPA-loaded liposomes (HA-RL) were fabricated by emulsion-solvent evaporation. The average size, zeta potential, entrapment efficiency were characterized, and the stability and drug release in vitro were investigated. Furthermore, the in vitro and in vivo lymphatic targeting ability were evaluated on lymphatic endothelial cells and LDLR-/- mice, and the efficiency of this nano-system in inducing the attenuation of atherosclerotic plaques was confirmed.

Results

HA-RL had a size of 100 nm, over 90% drug encapsulation efficiency, the storage stability was distinguished, demonstrating a slow release from the lipid nano-carriers. The mean retention time (MRT) and elimination half-life (t1/2β) achieved from HA-RL were 100.27±73.08 h and 70.74±50.80 h, respectively. HA-RL acquired the most prominent efficacy of lymphatic-targeted delivery and atherosclerotic plaques attenuation, implying the successful implementation of this novel drug delivery system in vivo.

Conclusion

HA-RL exhibited the most appreciable lymphatic targeting ability and best atherosclerotic plaques attenuation efficiency, opening a new paradigm and promising perspective for the treatment of arteriosclerosis.

Co-Delivery of Hesperetin and Cisplatin via Hyaluronic Acid-Modified Liposome for Targeted Inhibition of Aggression and Metastasis of Triple-Negative Breast Cancer

Having no specific therapy for triple-negative breast cancer (TNBC), this subtype has the lowest survival rate and highest metastatic risk of breast cancer since the tumor inflammatory microenvironment mainly accounts for heterogeneity-induced insensitivity to chemotherapy and epithelial-mesenchymal transition (EMT). This study reports hyaluronic acid (HA)-modified liposomes loaded with cisplatin (CDDP) and hesperetin (Hes) (CDDP-HA-Lip/Hes) for active targeting to relieve systematic toxicity and effective anti-tumor/anti-metastasis ability of TNBC. Our results revealed that HA modification promoted the cellular uptake of the synthesized CDDP-HA-Lip/Hes nanoparticles in MDA-MB-231 cells and accumulation in tumor sites in vivo, indicating deeper tumor penetration. Importantly, CDDP-HA-Lip/Hes inhibited the PI3K/Akt/mTOR pathway to alleviate the inflammation in the tumor and with a crosstalk to suppress the process of the EMT, increasing the chemosensitivity and inhibiting tumor metastasis. Meanwhile, CDDP-HA-Lip/Hes could significantly inhibit the aggression and metastasis of TNBC with less side effects on normal tissues. Overall, this study provides a tumor-targeting drug delivery system with great potential for treating TNBC and its lung metastasis robustly.

Interplay between mucus mobility and alveolar macrophage targeting of surface-modified liposomes

Alveolar macrophages play a crucial role in the initiation and resolution of the immune response in the lungs. Pro-inflammatory M1 alveolar macrophages are an interesting target for treating inflammatory and infectious pulmonary diseases. One commune targeting strategy is to use nanoparticles conjugated with hyaluronic acid, which interact with CD44 overexpressed on the membrane of those cells. Unfortunately, this coating strategy may be countered by the presence on the surface of the nanoparticles of a poly(ethylene glycol) corona employed to improve nanoparticles' diffusion in the lung mucus. This study aims to measure this phenomenon by comparing the behavior in a murine lung inflammation model of three liposomal platforms designed to represent different poly(ethylene glycol) and hyaluronic acid densities (Liposome-PEG, Liposome-PEG-HA and Liposome-HA). In this work, the liposomes were obtained by a one-step ethanol injection method. Their interaction with mucin and targeting ability toward pro-inflammatory macrophages were then investigated in vitro and in vivo in a LPS model of lung inflammation. In vitro, poly(ethylene glycol) free HA-liposomes display a superior targeting efficiency toward M1 macrophages, while the addition of poly(ethylene glycol) induces better mucus mobility. Interestingly in vivo studies revealed that the three liposomes showed distinct cell specificity with alveolar macrophages demonstrating an avidity for poly(ethylene glycol) free HA-liposomes, while neutrophils favored PEGylated liposomes exempt of HA. Those results could be explained by the presence of two forces exercising a balance between mucus penetration and receptor targeting. This study corroborates the importance of considering the site of action and the targeted cells when designing nanoparticles to treat lung diseases.

Multifunctional Gold Nanoclusters for Effective Targeting, Near-Infrared Fluorescence Imaging, Diagnosis, and Treatment of Cancer Lymphatic Metastasis

Developing effective lymph-node (LN) targeting and imaging probes is crucial for the early detection and diagnosis of tumor metastasis to improve patient survival. Most current clinical LN imaging probes are based on small organic dyes (e.g., indocyanine green) or radioactive ^99mTc-complexes, which often suffer from limitations, such as rapid photobleaching, poor signal contrast, and potential biosafety issues. Moreover, these probes cannot easily incorporate therapeutic functions to realize beneficial theranostics without affecting their LN-targeting ability. Herein, we have developed dual-ligand-/multiligand-capped gold nanoclusters (GNCs) for specific targeting, near-infrared (NIR) fluorescence imaging, diagnosis, and treatment of LN cancer metastasis in in vivo mouse models. By optimizing the surface ligand coating, we have prepared Au₂₅(SR₁)_n(SR₂)_18-n (where SR₁ and SR₂ are different functional thiol ligands)-type GNCs, which display highly effective LN targeting, excellent stability and biocompatibility, and optimal body-retention time. Moreover, they can provide continuous NIR fluorescence imaging of LNs for >3 h from a single dose, making them well-suited for fluorescence-guided surgery. Importantly, we have further incorporated methotrexate, a chemotherapeutic drug, into the GNCs without affecting their LN-targeting ability. Consequently, they can significantly improve the efficiency of methotrexate delivery to target LNs, achieving excellent therapeutic efficacy with up to 4-fold lower hepatotoxicity. Thus, the GNCs are highly effective and safe theranostic nanomedicines against cancer lymphatic metastasis.

Surface modified Genistein phytosome for Breast Cancer Treatment: In-vitro Appraisal, Pharmacokinetics, and In-vivo Antitumor Efficacy

Based on phytosomes advantages over liposomes, hyaluronic acid (HA) with/out pegylated phospholipid was used to develop surface-modified genistein (Gen) phytosome as Gen pegylated hyaluophytosomes (G-PHA) and Gen hyaluophytosomes (G-HA) as novel delivery systems for breast cancer treatment. In this study, in-vitro characterization of G-HA and G-PHA shows PS 144.2 ±1.266 nm and 220.3 ±2.51 nm, ZP -30.9 ±0.75 and -32.06 ±0.305 respectively. Morphological elucidation shows HA covers the surface of G-HA and the presence of a transparent layer of PEG surrounding G-PHA. In-vitro release shows a significant slow Gen release from G-HA, and G-PHA compared to Gen solution and Gen phytosomes. In-vivo bioavailability data shows improvement in bioavailability for G-HA and G-PHA compared to Gen suspension (AUC_0- T: :3.563 ±0.067, 2.092 ±0.058, 0.374 ±0.085 µg/ml*h respectively). Therapeutic evaluation of the prepared targeted formulations was carried out by subcutaneous injection in an EAC-induced breast cancer model in mice. G-HA and G-PHA show a promising chemotherapeutic effect in terms of lowering the tumor size and tumor biomarkers (CEA: -34.6, -44.7 & CA15.3: -77.8, -81.6 respectively). This reduction in their values compared to Gen phytosomes, Gen suspension, and the control group is attributed to high Gen accumulation at the target organ owing to targeting properties of HA that are used in phytosomal surface modification in G-HA. Additionally, the presence of MPEG₂₀₀₀-DSPE in G-PHA tends to improve interstitium lymphatic drainage following SC administration, resulting in maximizing the therapeutic benefits of breast cancer despite the difference in pharmacokinetics behavior compared to G-HA. These formulations can be further studied for metastatic breast cancer.

Resistance to TKIs in EGFR-Mutated Non-Small Cell Lung Cancer: From Mechanisms to New Therapeutic Strategies

Resistance to tyrosine kinase inhibitors (TKIs) of the epidermal growth factor receptor (EGFR) in advanced mutant Non-Small Cell Lung Cancer (NSCLC) constitutes a therapeutic challenge. This review intends to summarize the existing knowledge about the mechanisms of resistance to TKIs in the context of EGFR mutant NSCLC and discuss its clinical and therapeutic implications. EGFR-dependent and independent molecular pathways have the potential to overcome or circumvent the activity of EGFR-targeted agents including the third-generation TKI, osimertinib, negatively impacting clinical outcomes. CNS metastases occur frequently in patients on EGFR-TKIs, due to the inability of first and second-generation agents to overcome both the BBB and the acquired resistance of cancer cells in the CNS. Newer-generation TKIs, TKIs targeting EGFR-independent resistance mechanisms, bispecific antibodies and antibody-drug conjugates or combinations of TKIs with other TKIs or chemotherapy, immunotherapy and Anti-Vascular Endothelial Growth Factors (anti-VEGFs) are currently in use or under investigation in EGFR mutant NSCLC. Liquid biopsies detecting mutant cell-free DNA (cfDNA) provide a window of opportunity to attack mutant clones before they become clinically apparent. Overall, EGFR TKIs-resistant NSCLC constitutes a multifaceted therapeutic challenge. Mapping its underlying mutational landscape, accelerating the detection of resistance mechanisms and diversifying treatment strategies are essential for the management of the disease.

Lymphatic targeting for therapeutic application using nanoparticulate systems

The lymphatic system has grasped attention of researchers to a greater extent. The conventional methods of lymphatic delivery are now being modified to include nanotechnology to enhance the targeting of the drug at the specific pathological site. Scientists have worked successfully on different drug loaded nanocarriers that are modulated for the lymphatic system targeting for the treatment of various fatal diseases. Huge strides have been made in methods of delivery of these drugs either individually or in combination along with nanoparticles, therapeutic genes, and vaccines. However, the products introduced for commercial use are almost near nil. Altogether, there are challenges that need to be resolved and studies that are meant to be done for further improvements. The current review focuses on the understanding and pathophysiology of the lymphatic system and changes that occur during disease, drug characteristics, and physicochemical parameters that influence the lymphatic uptake of drugs and different nanocarriers. We further highlight different potential results obtained over the years with nanocarriers and other delivery methods to effectively target the lymphatic system for their therapeutic application. The challenges and drawbacks governing the lack of products available clinically have also been discussed.

Surface Modification of Lipid-Based Nanoparticles

There is a growing interest in the development of lipid-based nanocarriers for multiple purposes, including the recent increase of these nanocarriers as vaccine components during the COVID-19 pandemic. The number of studies that involve the surface modification of nanocarriers to improve their performance (increase the delivery of a therapeutic to its target site with less off-site accumulation) is enormous. The present review aims to provide an overview of various methods associated with lipid nanoparticle grafting, including techniques used to separate grafted nanoparticles from unbound ligands or to characterize grafted nanoparticles. We also provide a critical perspective on the usefulness and true impact of these modifications on overcoming different biological barriers, with our prediction on what to expect in the near future in this field.

Hyaluronic acid-modified liposomal honokiol nanocarrier: Enhance anti-metastasis and antitumor efficacy against breast cancer

In an effort to enhance antitumor and anti-metastasis of breast cancer, honokiol (HNK) was encapsulated into hyaluronic acid (HA) modified cationic liposomes (Lip). The prepared HA-Lip-HNK had a spherical shape with a narrow size distribution. The enhanced antitumor efficacy of HA-Lip-HNK was investigated in 4T1 cells in vitro, wherein flow cytometry and confocal microscopy analysis revealed its HA/CD44-mediated greater cellular internalization. As anticipate, the significant cytotoxicity of the HA-Lip-HNK was also observed in 4T1 tumor spheroids. Furthermore, the superior prevention of tumor metastasis by HA-Lip-HNK was verified by in vitro anti-invasion, wound healing and anti-migration assessments, and in vivo bioluminescence imaging in pulmonary metastasis model. Finally, compared with unmodified liposomes, the HA-Lip-HNK exhibited higher tumor accumulation, and achieved a tumor growth inhibition rate of 59.5 %. As a result, the HA-Lip-HNK may serve as a promising tumor-targeted drug delivery strategy for the efficient therapy of metastatic breast cancer.

Advances in nanotechnology-based delivery systems for EGFR tyrosine kinases inhibitors in cancer therapy

Oral tyrosine kinase inhibitors (TKIs) against epidermal growth factor receptor (EGFR) family have been introduced into the clinic to treat human malignancies for decades. Despite superior properties of EGFR-TKIs as small molecule targeted drugs, their applications are still restricted due to their low solubility, capricious oral bioavailability, large requirement of daily dose, high binding tendency to plasma albumin and initial/acquired drug resistance. Nanotechnology is a promising tool to improve efficacy of these drugs. Through non-oral routes. Various nanotechnology-based delivery approaches have been developed for providing efficient delivery of EGFR-TKIs with a better pharmacokinetic profile and tissue-targeting ability. This review aims to indicate the advantage of nanocarriers for EGFR-TKIs delivery.

Enhanced Intradermal Delivery of Nanosuspensions of Antifilariasis Drugs Using Dissolving Microneedles: A Proof of Concept Study

Conventional oral administration of antifilariasis drugs results in nonspecific targeting of the drugs and the intradermal delivery of nanoparticles with sizes of <100 nm could be used to improve lymphatic uptake. This study investigated the combination of nanosuspension and dissolving microneedles (MN-NS) as an alternative intradermal delivery approach for the delivery of antifilariasis drugs, namely doxycycline, albendazole, and ivermectin. NS were fabricated and optimized using a bottom-up technique. The NS were then incorporated into the MN arrays. The optimized NS were <100 nm in diameter. Furthermore, MN-NS had suitable mechanical strength and insertion capabilities. The dermatokinetic study revealed that the delivery of drugs into the dermis of excised neonatal porcine skin by MNs was significantly higher than that from a needle-free patch, with 29.29 ± 4.65%, 31.54 ± 5.35%, and 34.54 ± 4.98% of doxycycline, albendazole sulfoxide, and ivermectin retained in the dermis after 24 h. The results presented here serve as proof of concept for the significant enhancement of drug retention times in the dermis, following their formulation into NS and delivery via MN. Leading on from these studies, future work must investigate in vivo lymphatic pharmacokinetic profiling of drugs formulated into NS, in a suitable animal model.

Cabazitaxel and silibinin co-encapsulated cationic liposomes for CD44 targeted delivery: A new insight into nanomedicine based combinational chemotherapy for prostate cancer

Cancer stem cells (CSCs) are the promising targets for cancer chemotherapy that cannot be eliminated by conventional chemotherapy. In this study cationic liposomes of cabazitaxel (CBX) and silibinin (SIL) were prepared with an aim to kill cancer cells and CSCs for prostate cancer. CBX act as cancer cell inhibitor and SIL as CSC inhibitor. Hyaluronic acid (HA), an endogenous anionic polysaccharide was coated on cationic liposomes for targeting CD44 receptors over expressed on CSCs. Liposomes were prepared by ethanol injection method with particle size below 100 nm and entrapment efficiency of more than 90% at 10% w/w drug loading. Liposomes were characterized by dynamic light scattering, transmission electron microscopy, ¹H nuclear magnetic resonance and scanning electron microscopy-energy dispersive x-ray spectroscopy. Liposomes were evaluated for their anticancer action in androgen independent human prostate cancer cell lines (PC-3 and DU-145). HA coated liposomes showed potential cytotoxicity over other groups with low IC₅₀, significantly inhibited cell migration and induced apoptosis. Synergistic cytotoxic effect was also observed with HA coated liposomes that resulted in colony formation inhibition and G2/M phase arrest. Proficient cytotoxicity against CD44⁺ cells (14.87 ± 0.41% in PC-3 and 33.95 ± 0.68% in DU-145 cells) indicated the efficiency of HA coated liposomes towards CSC targeting. Hence, the outcome of this combinational therapy with CD44 targeting indicates the suitability of HA coated CBX and SIL co-loaded liposomes as a potential approach for eradicating prostate cancer and herein might provide a insight for future studies.

Improved lymphatic targeting: effect and mechanism of synthetic borneol on lymph node uptake of 7-ethyl-10-hydroxycamptothecin nanoliposomes following subcutaneous administration

Borneol as a penetration enhancer is widely used in guiding other components through the biological barrier into the targeting organs or tissues. This study aimed at studying effect and mechanism of synthetic borneol (S-BO) on improving lymphatic-targeting ability of 7-ethyl-10-hydroxycamptothecin liposomes (SN-38-Lips) via increasing lymph node uptake. At first, SN-38-Lips prepared had appropriate particle distribution, drug loading property and compatible stability with S-BO. Both in vitro cellular uptake and in vivo fluorescence imaging showed that 2 and 5 mg/mL S-BO, especially 2 mg/mL S-BO, enhanced cytoplasmic fluorescence signal of SN-38-Lips in the macrophages based on phagocytosis effect. And high-intensity zone appeared in the paracortex and medulla of popliteal lymph node. SN-38-Lips were subcutaneously (s.c.) injected into the right footpad of KM rats in the dose of 4 mg/kg following s.c. injection of 1, 2 and 5 mg/mL BO suspension. The lymphatic pharmacokinetics were investigated to explore the promotion law of S-BO, and combined with tissue irritation to optimize S-BO concentrations. The results indicated that 2 mg/mL S-BO could reduce injection-site retention, and prolong residence time and increase uptake of lymph nodes, which would not cause inflammatory reaction of injection site. In conclusion, the present study may provide a basic study for improving lymphatic-targeting ability of SN-38-Lips by the S-BO regulation, and to be the helpful guidance for further study in lymphatic targeting of delivery system.

Nanostructured lipid carrier-based pH and temperature dual-responsive hydrogel composed of carboxymethyl chitosan and poloxamer for drug delivery

The aim of this study was to develop a novel nanostructured lipid carrier (NLC) based dual-responsive hydrogel for ocular drug delivery of quercetin (QN). NLC loaded with quercetin (QN-NLC) was prepared using melt-emulsification combined with ultra-sonication technique. A three-factor five-level central composite design (CCD) was employed to optimize the formulation of QN-NLC. The optimized QN-NLC presented a particle size of 75.54nm with narrow size distribution and high encapsulation efficiency (97.14%).QN-NLC was characterized by TEM and DSC. In addition, a pH and temperature dual-responsive hydrogel composed of carboxymethyl chitosan (CMCS) and poloxamer 407(F127) was constructed by a cross-linking reaction with a naturally occurring nontoxic crosslinking agent genipin (GP). FT-IR was employed to demonstrate that F127/CMCS hydrogel was successfully synthesized. The results of SEM analysis and swelling experiments indicated that F127/CMCS hydrogel was both temperature-responsive and pH-responsive. From the results of In vitro release studies, dual temperature and pH responsiveness of the hydrogel was demonstrated, and 80.52% of total quercetin was released from the QN-NLC based hydrogel (QN-NLC-Gel) within 3days, revealing QN-NLC-Gel released drug sustainably. Taken together, the developed NLC-based hydrogel is a promising drug delivery system for the ophthalmic application.

Study on enhanced lymphatic tracing of isosulfan blue injection by influence of osmotic pressure on lymphatic exposure

Isosulfan blue (IB) is being used as a lymphatic tracer has been approved by the FDA in 1981. This study aimed at improving lymphatic exposure of IB injection by osmotic pressure regulation to achieve step-by step lymphatic tracing. First, IB injection with appropriate osmotic pressure, stability, and suitable pH was prepared. Next, the lymphatic tracing ability of different osmotic pressure was studied to determine the blue-stained state of IB in three-level lymph nodes after subcutaneous administration. Furthermore, pharmacokinetics of lymphatic drainage, lymph node uptake, and plasma concentration was investigate to explore the improving law of the lymphatic tracing by osmotic pressure, and combined with tissue irritation to determine the optimal osmotic pressure. At last, the tissue distribution in mice of IB injection which had the property of optimal osmotic pressure was investigated. The results showed that increasing osmotic pressure could significantly reduce injection site retention and increase IB concentration of lymph node. The lymph nodes could be obviously blue-stained by IB injection which had 938 mmol/kg osmotic pressure and would not cause inflammatory reaction and blood exposure. The tissue distribution study suggested that IB injection which had 938 mmol/kg osmotic pressure was mainly distributed into gallbladder and duodenum that verified the reports that 90% IB was excreted through the feces through biliary excretion. In conclusion, this study provides the basic study to improve lymphatic exposure of IB injection by regulate the osmotic pressure and have the potential to be the helpful guidance for the elective lymph node dissection.

CD44 targeting hyaluronic acid coated lapatinib nanocrystals foster the efficacy against triple-negative breast cancer

Lapatinib (LPT) is an orally administered drug for the treatment of metastatic breast cancer. For expanding its therapeutic horizon, we have prepared its nanocrystals (LPT-NCs) that were subsequently coated with hyaluronic acid (HA) to produce LPT-HA-NCs. The detailed in-vitro and in-vivo investigation of LPT-HA-NCs showed the superior anticancer activity due to active targeting to CD44 receptors than the counterparts LPT-NCs and free LPT. In the triple negative 4T1 cells induced breast tumor bearing female Balb/C mice; LPT-HA-NCs treatment caused significant retardation of tumor growth and overall increase in animal survival probability because of their higher tumor localization, increased residence time. Our findings clearly suggest that HA coated LPT-NCs formulation enhances the activity of LPT against triple negative breast cancer. It exhibited magnificent therapeutic outcome at low dose thus presenting a strategy to reduce dose administrations and minimize dose related toxicity.

Liposome-loaded thermo-sensitive hydrogel for stabilization of SN-38 via intratumoral injection: optimization, characterization, and antitumor activity

Main challenges of the clinical use of 7-ethyl-10-hydroxycamptothecin (SN-38) are its facile transition between the active lactone form (SN-38 A) and the inactive carboxylate form (SN-38I) under physiological conditions and its low solubility. The purpose of this study was to develop a thermo-sensitive hydrogel system with acidic SN-38 liposomes (SN-38-Lip-Gel) for local chemotherapy to solve these problems and to evaluate its antitumor activity and tissue distribution in tumor-bearing mice. A study of structural conversion between SN-38I and SN-38 A under various pH conditions indicated that acidic solution could inhibit the conversion. Namely, a preparation with low pH was essential to stabilize lactone form of SN-38. SN-38-Lip-Gel had an appropriate gelation time (GT) at 25/37 °C. The particle size of SN-38-Lip-Gel was similar to that of SN-38-Lip. SN-38-Lip-Gel showed a slower release than SN-38-Lip in vitro. SN-38-Lip-Gel suggested pH-dependent stability, the percentage of SN-38 A remaining decreased along with the increasing pH. In vivo studies SN-38-Lip-Gel showed better antitumor efficacy and lower systemic toxicity compared with other groups at the same drug dose. In conclusion, SN-38-Lip-Gel could improve the effective use of SN-38 by stabilizing the lactone form, extending the drug release, providing a high local drug concentration, and reducing systemic toxicity.

Exploiting lymphatic vessels for immunomodulation: Rationale, opportunities, and challenges

Lymphatic vessels are the primary route of communication from peripheral tissues to the immune system; as such, they represent an important component of local immunity. In addition to their transport functions, new immunomodulatory roles for lymphatic vessels and lymphatic endothelial cells have come to light in recent years, demonstrating that lymphatic vessels help shape immune responses in a variety of ways: promoting tolerance to self-antigens, archiving antigen for later presentation, dampening effector immune responses, and resolving inflammation, among others. In addition to these new biological insights, the growing field of immunoengineering has begun to explore therapeutic approaches to utilize or exploit the lymphatic system for immunotherapy.

Development of Timolol-Loaded Galactosylated Chitosan Nanoparticles and Evaluation of Their Potential for Ocular Drug Delivery

This study was conducted to develop timolol maleate (TM)-loaded galactosylated chitosan (GC) nanoparticles (NPs) (TM-GC-NPs) followed by optimization via a four-level and three-factor Box-Behnken statistical experimental design. The optimized nanoparticles showed a particle size of 213.3 ± 6.83 nm with entrapment efficiency of 38.58 ± 1.31% and drug loading of 17.72 ± 0.28%. The NPs were characterized with respect to zeta potential, pH, surface morphology, and differential scanning calorimetry (DSC). The determination of the oil-water partition coefficient demonstrated that the TM-GC-NPs had a high liposolubility at pH 6 as compared to timolol-loaded chitosan nanoparticles (TM-CS-NPs) and commercial TM eye drops. The in vitro release study indicated that TM-GC-NPs had a sustained release effect compared with the commercial TM eye drops. Ocular tolerance was studied by the hen's egg chorioallantoic membrane (HET-CAM) assay and the formulation was non-irritant and could be used for ophthalmic drug delivery. The in vitro transcorneal permeation study and confocal microscopy showed enhanced penetration, and retention in the cornea was achieved with TM-GC-NPs compared with the TM-CS-NPs and TM eye drops. Preocular retention study indicated that the retention of TM-GC-NPs was significantly longer than that of TM eye drops. The in vivo pharmacodynamic study suggested TM-GC-NPs had a better intraocular pressure (IOP) lowering efficacy and a prolonged working time compared to commercial TM eye drops (P ≤ 0.05). The optimized TM-GC-NPs could be prepared successfully promising their use as an ocular delivery system.

Hyaluronic acid-conjugated lipoplexes for targeted delivery of siRNA in a murine metastatic lung cancer model

We have investigated the impact of hyaluronic acid (HA)-coating on the targeting capacity of siRNA lipoplexes to CD44-overexpressing tumor cells. Cellular uptake and localization of HA-lipoplexes were evaluated by flow cytometry and fluorescence microscopy and both methods showed that these lipoplexes were rapidly internalized and localized primarily within the cytoplasm. Inhibition of luciferase expression on the A549-luciferase lung cancer cell line was achieved in vitro using an anti-Luc siRNA. 81% of luciferase gene expression inhibition was obtained in vitro with HA-lipoplexes at +/- ratio 2. In vivo, in a murine A549 metastatic lung cancer model, the treatment with HA-lipoplexes carrying anti-luciferase siRNA led to a statistically significant decrease of luciferase expression as opposed to progressive increase with non-modified lipoplexes or NaCl 0.9%. The reduction of the expression of luciferase mRNA tumor of mice treated with HA-lipoplexes supported the inhibition effect due to siRNA. These results highlight the potential of HA-lipoplexes in CD44-targeting siRNA delivery.

Docetaxel Accumulates in Lymphatic Circulation Following Subcutaneous Delivery Compared to Intravenous Delivery in Rats

BACKGROUND

The circulatory pathway for particles deposited outside of blood capillaries has not been well characterized for non-traditionally-delivered chemotherapeutics.

MATERIALS AND METHODS

Blood and lymph pharmacokinetics of docetaxel (5 mg/kg) and carboplatin (14 and 28 mg/kg) following subcutaneous (s.c.) versus intravenous (i.v.) delivery were determined in a rodent model with catheterizations of both the thoracic lymphatic duct and jugular vein for prolonged synchronous blood and lymph sampling.

RESULTS

Subcutaneous docetaxel demonstrates preferential lymphatic accumulation based on the area under the time-concentration curve (AUC_0-24h) whereas i.v. docetaxel resulted in a greater plasma maximum concentration measured (C_max). The apparent elimination half-life (t_1/2) in lymph for docetaxel is greater following i.v. or s.c. delivery compared to t_1/2 in blood. Carboplatin demonstrates a dose-dependent increase in plasma C_max regardless of delivery route; the total carboplatin exposure over 24 h in lymph and plasma are comparable.

CONCLUSION

Subcutaneous docetaxel achieves lymphatic accumulation greater than that of i.v. delivery.

Targeting cancer with hyaluronic acid-based nanocarriers: recent advances and translational perspectives

Hyaluronic acid is a natural polysaccharide that has been widely explored for the development of anticancer therapies due to its ability to target cancer cells. Moreover, advances made in the last decade have revealed the versatility of this biomaterial in the design of multifunctional carriers, intended for the delivery of a variety of bioactive molecules, including polynucleotides, immunomodulatory drugs and imaging agents. In this review, we aim to provide an overview of the major recent achievements in this field, highlighting the application of the newly developed nanostructures in combination therapies, immunomodulation and theranostics. Finally, we will discuss the main challenges and technological advances that will allow these carriers to be considered as candidates for clinical development.

Lipid-based nanosystems for CD44 targeting in cancer treatment: recent significant advances, ongoing challenges and unmet needs

Extensive experimental evidence demonstrates the important role of hyaluronic acid (HA)-CD44 interaction in cell proliferation and migration, inflammation and tumor growth. Taking advantage of this interaction, the design of HA-modified nanocarriers has been investigated for targeting CD44-overexpressing cells with the purpose of delivering drugs to cancer or inflammatory cells. The effect of such modification on targeting efficacy is influenced by several factors. In this review, we focus on the impact of HA-modification on the characteristics of lipid-based nanoparticles. We try to understand how these modifications influence particle physicochemical properties, interaction with CD44 receptors, intracellular trafficking pathways, toxicity, complement/macrophage activation and pharmacokinetics. Our aim is to provide insight in tailoring particle modification by HA in order to design more efficient CD44-targeting lipid nanocarriers.

Potential advantages of a novel chitosan-N-acetylcysteine surface modified nanostructured lipid carrier on the performance of ophthalmic delivery of curcumin

The transient precorneal retention time and low penetration capacity into intraocular tissues are the key obstacles that hinder the ophthalmic drug delivery of many therapeutic compounds, especially for drugs with poor solubility and permeability. To break the stalemate, N-acetyl-L-cysteine functionalized chitosan copolymer (CS-NAC), which exhibit marked bioadhesion and permeation enhancing effect, was synthesized. The curcumin encapsulated NLC (CUR-NLC) was produced and optimized followed by surface absorption of CS-NAC. After coating, changed particle size from 50.76 ± 2.21 nm to 88.64 ± 1.25 nm and reversed zeta potential from −20.38 ± 0.39 mV to 22.51 ± 0.34 mV was observed. The in vitro CUR release from NLC was slower than that of CUR-NLC and chitosan hydrochlorides (CH) coated NLC due to the inter and/or intramolecular disulfide formation of thiomers on the surface of nanocarriers. The modification also significantly enhanced transcorneal penetration compared with CH-NLC and the uncoated ones. The effect on bioadhesion and precorneal retention were evaluated by in vivo imaging technique and ocular pharmacokinetics studies revealing that the clearance of the formulations was significantly delayed in the presence of CS-NAC and the effect was positively related to the degree of thiolation. In summary, CS-NAC-NLC presented a series of notable advantages for ophthalmic drug application.

Hyaluronic acid-coated liposomes for targeted delivery of paclitaxel, in-vitro characterization and in-vivo evaluation

Breast cancer is the leading cause of cancer death in women. Chemotherapy is regarded as the most essential strategy in inhibiting the proliferation of tumor cells. Paclitaxel is a widely used taxane; however, the side effects of available Cremophor-based formulations and also the limitations of passive targeting uncovered an essential need to develop tumor-specific targeted nanocarriers. A hyaluronic acid targeted liposomal formulation of paclitaxel was prepared in which, hyaluronic acid was electrostatistically attracted to the surface of liposomes. Liposomes, had a particle size of 106.4±3.2nm, a weakly negative zeta potential of -9.7±0.8mV and an acceptable encapsulation efficiency of 92.1±1.7%. The release profile of liposomes in buffer showed that 95% of PTX was released during 40h. Confocal laser scanning microscopy and flow cytometry analysis showed the greater cellular internalization of coumarin-loaded liposomes compared to free coumarin. MTT assay on 4T1 and T47D cells demonstrated the stronger cytotoxic activity of liposomes in comparison to free paclitaxel. Cell cycle analysis showed that cells were mainly blocked at G2/M phases after 48h treatment with liposomes. In vivo real time imaging on 4T1 tumor-bearing mice revealed that the liposomal formulation mainly accumulated in the tumor area. Liposomes also had better antitumor efficacy against Cremophor-based formulation. In conclusion, hyaluronic acid targeted paclitaxel liposome can serve as a promising targeted formulation of paclitaxel for future cancer chemotherapy.

A Comparison of the Pharmacokinetics and Pulmonary Lymphatic Exposure of a Generation 4 PEGylated Dendrimer Following Intravenous and Aerosol Administration to Rats and Sheep

PURPOSE

Cancer metastasis to pulmonary lymph nodes dictates the need to deliver chemotherapeutic and diagnostic agents to the lung and associated lymph nodes. Drug conjugation to dendrimer-based delivery systems has the potential to reduce toxicity, enhance lung retention and promote lymphatic distribution in rats. The current study therefore evaluated the pharmacokinetics and lung lymphatic exposure of a PEGylated dendrimer following inhaled administration.

METHODS

Plasma pharmacokinetics and disposition of a 22 kDa PEGylated dendrimer were compared after aerosol administration to rats and sheep. Lung-derived lymph could not be sampled in rats and so lymphatic transport of the dendrimer from the lung was assessed in sheep.

RESULTS

Higher plasma concentrations were achieved when dendrimer was administered to the lungs of rats as a liquid instillation when compared to an aerosol. Plasma pharmacokinetics were similar between sheep and rats, although some differences in disposition patterns were evident. Unexpectedly, less than 0.5% of the aerosol dose was recovered in pulmonary lymph.

CONCLUSIONS

The data suggest that rats provide a relevant model for assessing the pharmacokinetics of inhaled macromolecules prior to evaluation in larger animals, but that the pulmonary lymphatics are unlikely to play a major role in the absorption of nanocarriers from the lungs.

Study on enhanced lymphatic exposure of polyamidoamin-alkali blue dendrimer for paclitaxel delivery and influence of the osmotic pressure on the lymphatic targeting

In this study, paclitaxel (PTX)-loaded polyamidoamin-alkali blue (PTX-P-AB) was prepared in order to investigate the intralymphatic targeting ability and anti-cancer effect after subcutaneous (s.c.) administration. The physicochemical properties and in vitro drug release were evaluated. The lymphatic drainage and lymph nodes (LNs) uptake were examined by pharmacokinetics and distribution recovery of PTX in plasma, LNs, injection site (IS) and tissues after s.c. injection in healthy mice and in tumor-bearing mice. The osmotic pressure of PTX-P-AB affecting the lymphatic targeting was studied. The anti-tumor activity of PTX-P-AB was investigated in mice bearing S180 metastatic tumors. Results showed that PTX-P-AB with suitable and stable physicochemical properties could be used for in vivo lymphatic studies, and displayed the more rapid lymphatic absorption, the higher AUC value in LNs, the longer LNs residence time and the higher metastasis-inhibiting rate compared with Taxol®. Enhanced lymphatic drainage from the IS and uptake into lymph by increasing the osmotic pressure of PTX-P-AB indicated that PTX-P-AB possesses the double function of lymphatic tracing and lymphatic targeting, and suggested the potential for the development of lymphatic targeting vectors and the lymphatic tracer for treatment and diagnosis.

Recent advances in lymphatic targeted drug delivery system for tumor metastasis

The lymphatic system has an important defensive role in the human body. The metastasis of most tumors initially spreads through the surrounding lymphatic tissue and eventually forms lymphatic metastatic tumors; the tumor cells may even transfer to other organs to form other types of tumors. Clinically, lymphatic metastatic tumors develop rapidly. Given the limitations of surgical resection and the low effectiveness of radiotherapy and chemotherapy, the treatment of lymphatic metastatic tumors remains a great challenge. Lymph node metastasis may lead to the further spread of tumors and may be predictive of the endpoint event. Under these circumstances, novel and effective lymphatic targeted drug delivery systems have been explored to improve the specificity of anticancer drugs to tumor cells in lymph nodes. In this review, we summarize the principles of lymphatic targeted drug delivery and discuss recent advances in the development of lymphatic targeted carriers.

Liposome incorporated ion sensitive in situ gels for opthalmic delivery of timolol maleate

This study was aimed to design a liposomal based ion-sensitive in situ ophthalmic delivery system of timolol maleate (TM). The TM liposome was produced by the reverse evaporation technique coupled with pH-gradients method (REVPR), and then was incorporated into deacetylated gellan gum gels. The TM liposome was demonstrated to be a round and uniform shape in TEM pictures. Compared with the TM eye drops, the TM liposome produced a 1.93 folds increase in apparent permeability coefficients (Papp), resulting in a significant increase of the corneal penetration. The TM-loaded liposome incorporated ion sensitive in situ gels (TM L-ISG) showed longer retention time on corneal surface compared with the eye drops using gamma scintigraphy technology. Draize testing showed that TM L-ISG was non-irritant for ocular tissues. The biggest efficacy of TM L-ISG occurred 30 min after eye drops administration, and efficacy disappeared after 240min. Then, compared with the eye drops, the optimal TM L-ISG could quickly reduce the intraocular pressure and the effective time was significantly longer (P≤0.05). These results indicate that liposome incorporated ion sensitive in situ gels have a potential ability for the opthalmic delivery.

Synthesis of a novel polyamidoamine dendrimer conjugating with alkali blue as a lymphatic tracer and study on the lymphatic targeting in vivo

In this study, a novel lymphatic tracer polyamidoamin-alkali blue (PAMAM-AB) was synthesized in order to evaluate the intra-lymphatic targeting ability and lymphatic tropism of PAMAM-AB after subcutaneous administration. UV-Vis, FT-IR, NMR and HPLC characterization were performed to prove the successful synthesis of PAMAM-AB. The calculated AB payload of PAMAM-AB conjugate was seven per dendrimer molecule (27.16% by weight). Hydrolysis stability of PAMAM-AB in vitro was evaluated, which was stable in PBS and human plasma. Lymphatic tracing were studied to determine the blue-stained intensity of PAMAM-AB in right popliteral lymph nodes (PLNs), iliac lymph nodes (ILNs) and para-aortic lymph nodes (PALNs) after subcutaneous administration. The pharmacokinetics and biodistribution of PAMAM-AB in mice were investigated. PLNs, ILNs and PALNs could be obviously blue-stained within 10 min after PAMAM-AB administration, and displayed a more rapid lymphatic absorption, a higher AUC value in lymph nodes and a longer lymph nodes residence time compared with methylene blue solution (MB-S), MB water-in-oil microemulsion (MB-ME), MB multiple microemulsion (MB-MME). Enhanced lymphatic drainage from the injection site and uptake into lymph of PAMAM-AB indicated that PAMAM-AB possesses the double function of lymphatic tracing and lymphatic targeting, and suggested the potential for the development of lymphatic targeting vectors or as a lymphatic tracer in its own right.