Long circulating liposomes: challenges and opportunities

Nanomedicine for pediatric healthcare: A review of the current state and future prospectives

Nanomedicine has emerged as a valuable treatment and diagnosis option, due to its ability not only to address formulation challenges associated with new therapeutic moieties, but also to improve the existing drugs efficacy. Nanomedicine provides appealing advantages such as increased drug payload, enhanced stability, tailored drug release profile, improved bioavailability and targeted drug delivery, etc. Tremendous research and regulatory efforts have been made in the past decades to advance nanomedicine from the benchtop to clinic. Numerous nanotechnology-based formulation approaches have been seen succeeding in commercialization. Despite the progress in nanomedicine use in adults, the advancement in pediatric population has been much slower. Clearly the treatment of disease in children cannot be simplified by dose adjustment based on body weight or surface, due to the significant differences in physiology thus the drug absorption, distribution, metabolism, excretion and transport (ADMET), between children and adults. This inherent variable among others poses much more challenges when developing pediatric-specific nanomedicine or translating adult nanodrug to pediatric indication. This review therefore intends to highlight the physiological differences between children and adult, and the common pediatric diseases which are good candidates for nanomedicine. The formulation approaches utilized in the marketed nanomedicine with pediatric indications, including liposomes, nanocrystals, polymeric nanoparticles and lipid nanoemulsions are elaborated. Finally, the challenges and gaps in pediatric nanomedicine development and commercialization, and the future prospectives are discussed.

Innovative Approaches to Enhancing the Biomedical Properties of Liposomes

Liposomes represent a promising class of drug delivery systems that enhance the therapeutic efficacy and safety of various pharmaceutical agents. Also, they offer numerous advantages compared to traditional drug delivery methods, including targeted delivery to specific sites, controlled release, and fewer side effects. This review meticulously examines the methodologies employed in the preparation and characterization of liposomal formulations. With the rising incidence of adverse drug reactions, there is a pressing need for innovative delivery strategies that prioritize selectivity, specificity, and safety. Nanomedicine promises to revolutionize diagnostics and treatments, addressing current limitations and improving disease management, including cancer, which remains a major global health challenge. This paper aims to conduct a comprehensive study on the interest of biomedical research regarding nanotechnology and its implications for further applications.

Calcium phosphates enhanced with liposomes - the future of bone regeneration and drug delivery

Effective healing and regeneration of various bone defects is still a major challenge and concern in modern medicine. Calcium phosphates have emerged as extensively studied bone substitute materials due to their structural and chemical resemblance to the mineral phase of bone, along with their versatile properties. Calcium phosphates present promising biological characteristics that make them suitable for bone substitution, but a critical limitation lies in their low osteoinductivity. To supplement these materials with properties that promote bone regeneration, prevent infections, and cure bone diseases locally, calcium phosphates can be biologically and therapeutically modified. A promising approach involves combining calcium phosphates with drug-containing liposomes, renowned for their high biocompatibility and ability to provide controlled and sustained drug delivery. Surprisingly, there is a lack of research focused on liposome-calcium phosphate composites, where liposomes are dispersed within a calcium phosphate matrix. This raises the question of why such studies are limited. In order to provide a comprehensive overview of existing liposome and calcium phosphate composites as bioactive substance delivery systems, the authors review the literature exploring the interactions between calcium phosphates and liposomes. Additionally, it seeks to identify potential interactions between calcium ions and liposomes, which may impact the feasibility of developing liposome-containing calcium phosphate composite materials. Liposome capacity to protect bioactive compounds and facilitate localized treatment can be particularly valuable in scenarios involving bone regeneration, infection prevention, and the management of bone diseases. This review explores the implications of liposomes and calcium phosphate material containing liposomes on drug delivery, bioavailability, and stability, offering insights into their advantages.

Liposome-Mediated Anti-Viral Drug Delivery Across Blood-Brain Barrier: Can Lipid Droplet Target Be Game Changers?

Lipid droplets (LDs) are subcellular organelles secreted from the endoplasmic reticulum (ER) that play a major role in lipid homeostasis. Recent research elucidates additional roles of LDs in cellular bioenergetics and innate immunity. LDs activate signaling cascades for interferon response and secretion of pro-inflammatory cytokines. Since balanced lipid homeostasis is critical for neuronal health, LDs play a crucial role in neurodegenerative diseases. RNA viruses enhance the secretion of LDs to support various phases of their life cycle in neurons which further leads to neurodegeneration. Targeting the excess LD formation in the brain could give us a new arsenal of antiviral therapeutics against neuroviruses. Liposomes are a suitable drug delivery system that could be used for drug delivery in the brain by crossing the Blood-Brain Barrier. Utilizing this, various pharmacological inhibitors and non-coding RNAs can be delivered that could inhibit the biogenesis of LDs or reduce their sizes, reversing the excess lipid-related imbalance in neurons. Liposome-Mediated Antiviral Drug Delivery Across Blood-Brain Barrier. Developing effective antiviral drug is challenging and it doubles against neuroviruses that needs delivery across the Blood-Brain Barrier (BBB). Lipid Droplets (LDs) are interesting targets for developing antivirals, hence targeting LD formation by drugs delivered using Liposomes can be game changers.

Progress and prospect of nanotechnology for cardiac fibrosis treatment

Cardiac fibrosis is the excessive accumulation of extracellular matrix components in the heart, leading to reduced cardiac functionality and heart failure. This review provides an overview of the therapeutic applications of nanotechnology for the treatment of cardiac fibrosis. We first delve into the fundamental pathophysiology of cardiac fibrosis, highlighting the key molecular players, including Matrix Metalloproteinases, Transforming Growth Factor-beta, and several growth factors, cytokines, and signaling molecules. Each target presents a unique opportunity to develop targeted nano-therapies. We then focus on recent advancements in nanotechnology and how nanoparticles can be engineered to deliver drugs or therapeutic genes. These advanced delivery approaches have shown significant potential to inhibit fibrosis-promoting factors, thereby mitigating the fibrotic response and potentially reversing disease progression. In addition, we discuss the challenges associated with developing and translating nanotechnology-based drug delivery systems, including ensuring biocompatibility, safety, and regulatory compliance. This review highlights how nanotechnology can bridge the gap between lab research and clinical practice for treating cardiac fibrosis.

Gout therapeutics and drug delivery

Gout is a common inflammatory arthritis caused by persistently elevated uric acid levels. With the improvement of people's living standards, the consumption of processed food and the widespread use of drugs that induce elevated uric acid, gout rates are increasing, seriously affecting the human quality of life, and becoming a burden to health systems worldwide. Since the pathological mechanism of gout has been elucidated, there are relatively effective drug treatments in clinical practice. However, due to (bio)pharmaceutical shortcomings of these drugs, such as poor chemical stability and limited ability to target the pathophysiological pathways, traditional drug treatment strategies show low efficacy and safety. In this scenario, drug delivery systems (DDS) design that overcome these drawbacks is urgently called for. In this review, we initially describe the pathological features, the therapeutic targets, and the drugs currently in clinical use and under investigation to treat gout. We also comprehensively summarize recent research efforts utilizing lipid, polymeric and inorganic carriers to develop advanced DDS for improved gout management and therapy.

A (Traditional Chinese Medicine) TCM-Inspired Doxorubicin Resistance Reversing Strategy: Preparation, Characterization, and Application of a Co-loaded pH-Sensitive Liposome

In this study, nano-strategy for combined medication of active compounds from traditional Chinese medicine herbs was proposed to achieve the synergistic effects of inhibiting the doxorubicin (DOX) resistance, reducing the cardio-toxicity, and improving the treatment efficacy simultaneously. Dihydroartemisinin (DHA) and tetrandrine (TET) were co-delivered for the first time to treat DOX resistance of breast cancer with multi-pathway mechanism. Tumor micro-environment sensitivity prescription was adopted to enhance the reversal effect of DOX resistance nearly 50 times (resistance index, RI was 46.70) and uptake ability. The DHA-TET pH-sensitive liposomes (DHA-TET pH-sensitive LPs) had a good spherical structure and a uniform dispersion structure with particle size, polydispersity index (PDI), and zeta potential of 112.20 ± 4.80 nm, 0.20 ± 0.02, and - 8.63 ± 0.74 Mv, and was stable until 14 days under the storage environment of 4°C and for 6 months at room temperature environment. With the DOX resistance reversing ability increased, the inhibition effect of DHA-TET pH-sensitive LPs on both MCF-7/ADR cells and MCF-7 cells was significantly enhanced; meanwhile, the toxicity on cardiac cell (H9c2) was lowered. Ferroptosis induced by the DHA was investigated showing that the intracellular reactive oxygen species (ROS) and lipid peroxidation were increased to promote the synergistic effect through the due-loaded nano-carrier, providing a promising alternative for future clinical application.

Preparation of an HI-6-loaded brain-targeted liposomes based on the nasal delivery route and the evaluation of its reactivation of central toxic acetylcholinesterase

PURPOSE

Organophosphorus compounds (OPs) is a serious threat to human health and life safety, but because of the existence of blood-brain barrier, most of the therapeutic drugs cannot enter the center, reactivate centrally located toxic acetylcholinesterase (AChE), it is urgent to find an efficient treatment method.

METHODS

The c(RGDyK) cyclic peptide modified HI-6-loaded brain targeting liposomes [c(RGDyK)-PEG₂₀₀₀HI-6-lipo] were prepared by ammonium sulfate gradient method. The in vitro blood-brain barrier (BBB) model was established, and the function of the liposomes was evaluated. The animal model of DDVP poisoning was established, and the central toxic enzyme reactivation ability of c(RGDyK)-PEG₂₀₀₀HI-6-lipo by both the intravenous and nasal administration route was verified.

RESULTS

The HI-6-loaded liposomes with brain targeting function were successfully synthesized and prepared with high encapsulation efficiency (70.23 ± 2.18%), drug loading (2.86 ± 0.07)%, average particle size 242.9 nm (polydispersion index 0.149), and ζ potential -16.2 mV. Combined with the in vitro and in vivo studies, the c(RGDyK)-PEG₂₀₀₀HI-6-lipo has better ability to cross the BBB. In addition, compared with intravenous injection, nasal administration was proved to be more effective against organophosphorus poisoning, and the reactivation rate of brain acetylcholinesterase reached (26.19 ± 7.70)%.

CONCLUSION

The prepared c(RGDyK)-PEG₂₀₀₀HI-6-lipo has a better ability to cross BBB. Nasal administration, as a way to bypass the BBB and directly deliver drugs into the brain, effectively improves the bioavailability of HI-6 in the brain. This study holds promise by providing a non-invasive approach to deliver water-soluble oxime antidote into the brain and reactivate central acetylcholinesterase via the naso-brain route.

Liposome-based diagnostic and therapeutic applications for pancreatic cancer

Pancreatic cancer is one of the harshest and most challenging cancers to treat, often labeled as incurable. Chemotherapy continues to be the most popular treatment yet yields a very poor prognosis. The main barriers such as inefficient drug penetration and drug resistance, have led to the development of drug carrier systems. The benefits, ease of fabrication and modification of liposomes render them as ideal future drug delivery systems. This review delves into the versatility of liposomes to achieve various mechanisms of treatment for pancreatic cancer. Not only are there benefits of loading chemotherapy drugs and targeting agents onto liposomes, as well as mRNA combined therapy, but liposomes have also been exploited for immunotherapy and can be programmed to respond to photothermal therapy. Multifunctional liposomal formulations have demonstrated significant pre-clinical success. Functionalising drug-encapsulated liposomes has resulted in triggered drug release, specific targeting, and remodeling of the tumor environment. Suppressing tumor progression has been achieved, due to their ability to more efficiently and precisely deliver chemotherapy. Currently, no multifunctional surface-modified liposomes are clinically approved for pancreatic cancer thus we aim to shed light on the trials and tribulations and progress so far, with the hope for liposomal therapy in the future and improved patient outcomes. STATEMENT OF SIGNIFICANCE: Considering that conventional treatments for pancreatic cancer are highly associated with sub-optimal performance and systemic toxicity, the development of novel therapeutic strategies holds outmost relevance for pancreatic cancer management. Liposomes are being increasingly considered as promising nanocarriers for providing not only an early diagnosis but also effective, highly specific, and safer treatment, improving overall patient outcome. This manuscript is the first in the last 10 years that revises the advances in the application of liposome-based formulations in bioimaging, chemotherapy, phototherapy, immunotherapy, combination therapies, and emergent therapies for pancreatic cancer management. Prospective insights are provided regarding several advantages resulting from the use of liposome technology in precision strategies, fostering new ideas for next-generation diagnosis and targeted therapies of pancreatic cancer.

Stealth nanoparticles in oncology: Facing the PEG dilemma

Nanoparticles (Nps) have revolutionized the landscape of many treatments, by modifying not only pharmacokinetic properties of the encapsulated agent, but also providing a significant protection of the drug from non-desired interactions, and reducing side-effects of the enclosed therapeutic, enabling co-encapsulation of possibly synergistic compounds or activities, allowing a controlled release of content and improving the therapeutic effect. Nevertheless, in systemic circulation, Nps suffer a rapid removal by opsonisation and the action of Mononuclear phagocyte system (MPS). To overcome this problem, different polymers, in particular Polyethyleneglycol (PEG), have been used to cover the surface of these nanocarriers forming a hydrophilic layer that allows the delay of the removal. These advantages contrast with some drawbacks such as the difficulty to interact with cell membranes and the development of immunological reactions, conforming the known, "PEG dilemma". To address and minimize this phenomenon, different strategies have been applied. Therefore, this review aims to summarize the state of the art of Pegylation strategies, comment in depth on the principal characteristics of PEG and describe the main alternatives, which are the use of cleavable PEG, addition of different polymers or even use other derivatives of cell membranes to camouflage Nps.

Liposomes as Multifunctional Nano-Carriers for Medicinal Natural Products

Although medicinal natural products and their derivatives have shown promising effects in disease therapies, they usually suffer the drawbacks in low solubility and stability in the physiological environment, low delivery efficiency, side effects due to multi-targeting, and low site-specific distribution in the lesion. In this review, targeted delivery was well-guided by liposomal formulation in the aspects of preparation of functional liposomes, liposomal medicinal natural products, combined therapies, and image-guided therapy. This review is believed to provide useful guidance to enhance the targeted therapy of medicinal natural products and their derivatives.

Alginate-Chitosan Coated Nanoliposomes as Effective Delivery Systems for Bamboo Leaf Flavonoids: Characterization, In Vitro Release, Skin Permeation and Anti-Senescence Activity

The use of bamboo leaf flavonoids (BLF) as functional food and cosmetic ingredients is limited by low bioavailability and difficulty in being absorbed by the intestine or skin. The aim of this study was to prepare BLF-loaded alginate-chitosan coated nanoliposomes (AL-CH-BLF-Lip) to overcome these challenges. The nanocarriers were characterized by dynamic light scattering, high performance liquid chromatography, Fourier transform infrared spectroscopy and differential scanning calorimetry. The biological activity was analyzed by in vitro antioxidant activity, transdermal absorption, cytotoxicity and AAPH induced HaCaT cell senescence model. The results showed that the size of nanocarriers ranged from 152.13 to 228.90 nm and had a low polydispersity index (0.25−0.36). Chitosan (CH) and alginate (AL) were successfully coated on BLF-loaded nanoliposomes (BLF-Lip), the encapsulation efficiency of BLF-Lip, BLF-loaded chitosan coated nanoliposomes (CH-BLF-Lip) and AL-CH-BLF-Lip were 71.31%, 78.77% and 82.74%, respectively. In addition, BLF-Lip, CH-BLF-Lip and AL-CH-BLF-Lip showed better in vitro release and free radical scavenging ability compared with naked BLF. In particular, the skin permeability of BLF-Lip, CH-BLF-Lip, and AL-CH-BLF-Lip increased 2.1, 2.4 and 2.9 times after 24 h, respectively. Furthermore, the use of nanoliposomes could significantly improve the anti-senescence activity of BLF (p < 0.01). Conclusively, alginate-chitosan coated nanoliposomes are promising delivery systems for BLF that can be used in functional foods and cosmetics.

Research Progress of Quercetin Delivery Systems

Quercetin is the main dietary flavonoid with a wide range of pharmacological activities. However, the poor gastrointestinal absorption and low bioavailability of quercetin curtails its clinical applications.. Enhancement the bioavailability of quercetin focuses on the application of delivery systems technologies such as microparticle delivery systems, solid dispersions, encapsulation, phospholipid complexes, and hydrogels , which have been systematically reviewed .And theirapplications in vitro and in vivo animal experiments also been described, promoting the development and optimization of drug delivery system for clinical applications.

Non-Viral Vectors for Delivery of Nucleic Acid Therapies for Cancer

The research and development of non-viral gene therapy has been extensive over the past decade and has received a big push thanks to the recent successful approval of non-viral nucleic acid therapy products. Despite these developments, nucleic acid therapy applications in cancer have been limited. One of the main causes of this has been the imbalance in development of delivery vectors as compared with sophisticated nucleic acid payloads, such as siRNA, mRNA, etc. This paper reviews non-viral vectors that can be used to deliver nucleic acids for cancer treatment. It discusses various types of vectors and highlights their current applications. Additionally, it discusses a perspective on the current regulatory landscape to facilitate the commercial translation of gene therapy.

Lipid-based nanoparticulate delivery systems for HER2-positive breast cancer immunotherapy

Lipid-based nanoparticulate delivery platforms such as liposomes help overcome cell and tissue barriers and allow prolonged therapeutic plasma drug concentrations, simultaneous targeting of tumor tissue, and increased bioavailability of numerous drugs used for treatment of cancer. The human epidermal growth factor receptor, HER2, is an important player in the pathogenesis of breast cancer and is considered a potential cancer biomarker for the design of immunotherapeutics. HER2-positive breast cancer is found in up to 30% of breast cancer patients. Currently, a variety of lipid nanoparticulate systems are being evaluated in preclinical settings and in clinical trials for targeting HER2-positive breast cancer. Advances in functionalized anti-HER2 lipid nanoparticulates have demonstrated promise and may lead to the development of new nano-immunotherapy protocols against HER2 positive breast cancer. Here we present a review of the most up-to-date literature, including our own research, on the use of lipid nanoparticulate carriers in immunotherapy of HER2-positive breast cancer.

Systematic review on activity of liposomal encapsulated antioxidant, antibiotics, and antiviral agents

Reactive oxygen species (ROS) like superoxide anion, hydrogen peroxide, and hydroxyl radical, can be formed as normal products of aerobic metabolism. Overproduction or insufficient removal of ROS results in significant damage to cell structure and functions. Antioxidants applied directly and at relatively high concentrations to cellular systems are effective in protection against the damaging actions of ROS. Microorganisms including Gram-positive and negative bacteria, fungi, protozoa, algae, etc., can be disease causing microorganism. Antimicrobial agents have the capability to inhibitor destroy the microorganisms. The problems arising from the use of antioxidant and antimicrobial agents include poor solubility, instability during storage, low bioavailability, and difficulty to reach target organs with sufficient doses. Liposomal antimicrobial agent and liposomal antioxidants enhance the solubility, bioavailability, and stability of antimicrobial agent and antioxidants.

Metal-organic frameworks (MOFs) as host materials for the enhanced delivery of biomacromolecular therapeutics

Biomacromolecular drugs have become an important class of therapeutic agents for the treatment of human diseases. Considering their high propensity for being degraded in the human body, the choice of an appropriate delivery system is key to ensure the therapeutic efficacy of biomacromolecular drugs in vivo. As an emerging class of supramolecular "host" materials, metal-organic frameworks (MOFs) exhibit advantages in terms of the tunability of pore size, encapsulation efficiency, controllable drug release, simplicity in surface functionalization and good biocompatibility. As a result, MOF-based host-guest systems have been extensively developed as a new class of flexible and powerful platform for the delivery of therapeutic biomacromolecules. In this review, we summarize current research progress in the synthesis of MOFs as delivery materials for a variety of biomacromolecules. Firstly, we briefly introduce the advances made in the use of biomacromolecular drugs for disease therapy and the types of commonly used clinical delivery systems. We then describe the advantages of using MOFs as delivery materials. Secondly, the strategies for the construction of MOF-encapsulated biomacromolecules (Biomacromolecules@MOFs) and the release mechanisms of the therapeutics are categorized. Thirdly, the application of MOFs to deliver different types of biomacromolecules (e.g., antigens/antibodies, enzymes, therapeutic proteins, DNA/RNA, polypeptides, and polysaccharides) for the treatment of various human diseases based on immunotherapy, gene therapy, starvation therapy and oxidation therapy is summarized. Finally, the remaining challenges and available opportunities for MOFs as drug delivery systems are outlined, which we anticipate will encourage additional research efforts directed towards developing Biomacromolecules@MOFs systems for biomedical applications.

Red blood cells: The metamorphosis of a neglected carrier into the natural mothership for artificial nanocarriers

Drug delivery research pursues many types of carriers including proteins and other macromolecules, natural and synthetic polymeric structures, nanocarriers of diverse compositions and cells. In particular, liposomes and lipid nanoparticles represent arguably the most advanced and popular human-made nanocarriers, already in multiple clinical applications. On the other hand, red blood cells (RBCs) represent attractive natural carriers for the vascular route, featuring at least two distinct compartments for loading pharmacological cargoes, namely inner space enclosed by the plasma membrane and the outer surface of this membrane. Historically, studies of liposomal drug delivery systems (DDS) astronomically outnumbered and surpassed the RBC-based DDS. Nevertheless, these two types of carriers have different profile of advantages and disadvantages. Recent studies showed that RBC-based drug carriers indeed may feature unique pharmacokinetic and biodistribution characteristics favorably changing benefit/risk ratio of some cargo agents. Furthermore, RBC carriage cardinally alters behavior and effect of nanocarriers in the bloodstream, so called RBC hitchhiking (RBC-HH). This article represents an attempt for the comparative analysis of liposomal vs RBC drug delivery, culminating with design of hybrid DDSs enabling mutual collaborative advantages such as RBC-HH and camouflaging nanoparticles by RBC membrane. Finally, we discuss the key current challenges faced by these and other RBC-based DDSs including the issue of potential unintended and adverse effect and contingency measures to ameliorate this and other concerns.

Improved oral delivery of insulin by PLGA nanoparticles coated with 5β-cholanic acid conjugated glycol chitosan

Oral insulin has been regarded as the best alternative to insulin injection in therapy of diabetes because of its convenience and painlessness. However, several obstacles in the gastrointestinal tract, such as gastric acid and enzyme, greatly reduce the bioavailability of oral insulin. Herein, we report design and preparation of poly (d, l-lactic-co-glycolic acid) nanoparticles (PLGA NPs) coated with 5β-cholanic acid modified glycol chitosan (GC-CA) (GC-CA@PLGA NPs) to improve the oral delivery of insulin. The GC-CA@PLGA NPs with the size of (302.73 ± 5.13 nm) and zeta potential of (25.03 ± 0.31 mV) were synthesized using the double-emulsion method. The insulin-loading capacity and encapsulation efficiency were determined to be 5.77 ± 0.58% and 51.99 ± 5.27%, respectively. Compared with GC-modified PLGA NPs (GC@PLGA NPs) and bare PLGA NPs, the GC-CA@PLGA NPs showed excellent stability and uptake by Caco-2 cells after simulated gastric acid digestion. Further experiment suggests good biocompatibility of GC-CA@PLGA NPs, including hemolysis and cytotoxicity. Inin vivoexperiment, the insulin loaded in the GC-CA@PLGA NPs exhibited a long-term and stable release profile for lowering blood glucose and presented 30.43% bioavailability in oral administration. In brief, we have developed an efficient and safe drug delivery system, GC-CA@PLGA NPs, for significantly improved oral administration of insulin, which may find potential application in the treatment of diabetes.

Perspectives in Breast and Ovarian Cancer Chemotherapy by Nanomedicine Approach: Nanoformulations in Clinical Research

BACKGROUND

Breast and ovarian carcinomas represent major health problems in women worldwide. Chemotherapy constitutes the main treatment strategy, and the use of nanocarriers, a good tool to improve it. Several nanoformulations have already been approved, and others are under clinical trials for the treatment of both types of cancers.

OBJECTIVE

This review focuses on the analysis of the nanoformulations that are under clinical research in the treatment of these neoplasms.

RESULTS

Currently, there are 6 nanoformulations in clinical trials for breast and ovarian carcinomas, most of them in phase II and phase III. In the case of breast cancer treatment, these nanomedicines contain paclitaxel; and, for ovarian cancer, nanoformulations containing paclitaxel or camptothecin analogs are being evaluated. The nanoencapsulation of these antineoplastics facilitates their administration and reduces their systemic toxicity. Nevertheless, the final approval and commercialization of nanoformulations may be limited by other aspects like lack of correlation between the efficacy results evaluated at in vitro and in vivo levels, difficulty in producing large batches of nanoformulations in a reproducible manner and high production costs compared to conventional formulations of antineoplastics. However, these challenges are not insurmountable and the number of approved nanoformulations for cancer therapy is growing.

CONCLUSION

Reviewed nanoformulations have shown, in general, excellent results, demonstrating a good safety profile, a higher maximum tolerated dose and a similar or even slightly better antitumor efficacy compared to the administration of free drugs, reinforcing the use of nano-chemotherapy in both breast and ovarian tumors.

Liposome-Coated Arsenic-Manganese Complex for Magnetic Resonance Imaging-Guided Synergistic Therapy Against Carcinoma

Purpose

A liposome-coated arsenic-manganese complex, denoted as LP@MnAs_x was constructed for the targeted delivery of arsenic trioxide (ATO) against carcinoma.

Methods

Arsenite, the prodrug of ATO, was encapsulated within a liposome via electrostatic interaction with the manganese ions. The as-prepared material was characterized with dynamic light scattering and transmission electron microscopy. The entrapment efficiency and drug loading of arsenic in the carrier were measured using inductively coupled plasma spectrometry. The in vitro release of arsenic was evaluated by using the dialysis bag method. Furthermore, the Fenton-like activity and in vitro cytodynamics research of LP@MnAs_x were monitored in this work. And the cellular uptake study was used to investigate the in vitro entry mechanism. Furthermore, the cytotoxicity, cell apoptosis and cell cycle study were performed to evaluate the tumor-killing efficiency. Also, the pharmacokinetic and antitumor studies were investigated in HepG2 tumor-bearing nude mice.

Results

The as-prepared LP@MnAs_x possessed a spherical morphology, uniformly distributed hydrodynamic diameter, and excellent drug-loading efficiency. LP@MnAs_x displayed robust stability and sustained-release profile under physiological environments. LP@MnAs_x could degrade with high sensitivity to the pH variation in the tumor microenvironment. As such, this could lead to a burst release profile of Mn²⁺ and arsenite to achieve a synergistic therapy of chemodynamic therapy and chemotherapy. When compared to the carrier-free arsenate, in vitro experiments revealed that LP@MnAs_x exhibited enhanced cellular uptake and tumor-killing efficiency. LP@MnAs_x also demonstrated significantly enhanced tumor-specific in vivo distribution of arsenic, prolonged systemic circulation lifetime, and increased accumulation at the tumor site.

Conclusion

Based on the experimental results, LP@MnAs_x is an ideal arsenic-based nanodelivery system, whereby it can improve the non-specific distribution of NaAsO₂ in vivo. Thus, this work can expand the research and application of arsenic trioxide against solid tumors.

Using Liposomes to Alleviate the Toxicity of Chelerythrine, a Natural PKC Inhibitor, in Treating Non-Small Cell Lung Cancer

Aim of the Study

CHE can inhibit the proliferation of lung cancer cells and induce apoptosis. However, despite having in vivo toxicity, CHE has not been thoroughly investigated in term of its in vivo antitumor effect. The present study evaluated the antitumor effect of CHE on non-small cell lung cancer cell line HCC827.

Methods

The antitumor effect of CHE on HCC827 was evaluated, and its potential work mechanism was investigated. CHE long circulation liposomes (CHELPs) modified with polyethylene glycol have been optimized and characterized by in vivo pharmacokinetic studies. A HCC827 xenograft model was developed on BALB/c nude mice for the assessment of the effects of CHE and CHELP.

Results

CHE might inhibit HCC827 growth through the ROS/PKC-ϵ/caspase 3 pathway and glycolysis. The optimized CHELP remained stable after storage for 10 days at 4°C and exhibited sustained drug release, showing approximately one-fifteenth of the in vivo clearance rate and 86 times the absorption concentration of free drug. While increasing the bioavailability of CHE, CHELP showed a good therapeutic effect on HCC827 tumor-bearing nude mice and reduced the toxicity of the free drug, improving the safety of CHE.

Conclusions

CHE is a candidate drug for NSCLC, and liposomes are effective in alleviating the toxicity of CHE.

Liposomal Nanomedicine: Applications for Drug Delivery in Cancer Therapy

The increasing prevalence of cancer, a disease in which rapid and uncontrollable cell growth causes complication and tissue dysfunction, is one of the serious and tense concerns of scientists and physicians. Nowadays, cancer diagnosis and especially its effective treatment have been considered as one of the biggest challenges in health and medicine in the last century. Despite significant advances in drug discovery and delivery, their many adverse effects and inadequate specificity and sensitivity, which usually cause damage to healthy tissues and organs, have been great barriers in using them. Limitation in the duration and amount of these therapeutic agents' administration is also challenging. On the other hand, the incidence of tumor cells that are resistant to typical methods of cancer treatment, such as chemotherapy and radiotherapy, highlights the intense need for innovation, improvement, and development in antitumor drug properties. Liposomes have been suggested as a suitable candidate for drug delivery and cancer treatment in nanomedicine due to their ability to store drugs with different physical and chemical characteristics. Moreover, the high flexibility and potential of liposome structure for chemical modification by conjugating various polymers, ligands, and molecules is a significant pro for liposomes not only to enhance their pharmacological merits but also to improve the effectiveness of anticancer drugs. Liposomes can increase the sensitivity, specificity, and durability of these anti-malignant cell agents in the body and provide remarkable benefits to be applied in nanomedicines. We reviewed the discovery and development of liposomes focusing on their clinical applications to treat diverse sorts of cancers and diseases. How the properties of liposomal drugs can be improved and their opportunity and challenges for cancer therapy were also considered and discussed.

Preparation of Fraxetin Long Circulating Liposome and Its Anti-enteritis Effect

This study sought to improve the oral bioavailability and enhance the anti-enteritis effect of fraxetin by incorporating it into long circulating liposomes (F-LC-Lipo). The optimal formulation of F-LC-Lipo was obtained via orthogonal design. The particle size, morphology, encapsulation efficiency, stability, and anti-enteritis effect of F-LC-Lipo were evaluated. The particle size of F-LC-Lipo was 166.65 ± 8.75 nm with entrapment efficiency (EE) of 92.18 ± 0.17%. The release rate in different dissolution media (pH 1.2 HCl, DDW, and pH 7.4 PBS) was significantly higher than that of fraxetin solution. Compared with the free fraxetin solution, F-LC-Lipo increased oral bioavailability of fraxetin by 4.43 times (443%). More importantly, F-LC-Lipo could improve the levels of interleukin-1 beta (IL-1β), IL-6, malondialdehyde (MDA), superoxide dismutase (SOD), tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), prostaglandin E2 (PEG2), and IL-10 in rats with enteritis. Overall, these results suggested that LC-Lipo may serve as a potential carrier for improving the solubility and oral bioavailability of fraxetin as well as improving its enteritis effect.

Effect of hydrophobically modified PEO polymers (PEO-dodecyl) on oil/water microemulsion properties: in vitro and in silico investigations

Microemulsions are excellent systems for transdermal delivery of multifunctional drugs because they have the potential to improve drug absorption/permeation and handling limitations. Biocompatible polymers are used as a coating of microemulsions to avoid the interactions that can occur between the microemulsions and the skin. Thus, they protect and lubricate these transporter nanovesicles. In this paper, we studied decane/water microemulsions covered with hydrophobically modified PEO polymer (PEO-m). To reveal the effect of hydrophobically modified PEO (PEO-m) polymer on the shape, the micro-arrangement and the dynamics of the microemulsions, we used an integrated strategy combining Molecular Dynamics simulation (MD), Small-Angle Neutron Scattering experiments (SANS), and the Ornstein-Zernike integral equations with the Hypernetted Chain (HNC) closure relation. We determined the microemulsion shape in vitro using the renormalized intensities spectra from SANS experiments. We discussed the micro arrangements of microemulsions, in vitro and in silico, employing the pair correlation function g(r) and the structure factor S(q), obtained from the three approaches with good agreement. Thus, we used the validated MD simulations to calculate the microemulsion's dynamics properties that we discussed using the mean-squared displacement (MSD) and the diffusion coefficients. We found that the presence of moderate quantities of PEO-m, from 4 to 12 PEO-m per microemulsion, does not influence the microemulsion shape, increases the stability of the microemulsion, and slightly decrease the dynamics. Our in vitro and in silico results suggest that polymer incorporation, which has interesting in vivo implications, has no disadvantageous effects on the microemulsion properties.

Ultra-small lipid nanoparticles encapsulating sorafenib and midkine-siRNA selectively-eradicate sorafenib-resistant hepatocellular carcinoma in vivo

Hepatocellular carcinoma (HCC) is a fatal disease with limited therapeutic choices. The stroma-rich tumor microenvironment hinders the in vivo delivery of most nanomedicines. Ultra-small lipid nanoparticles (usLNPs) were designed for the selective co-delivery of the cytotoxic drug, sorafenib (SOR), and siRNA against the Midkine gene (MK-siRNA) to HCC in mice. The usLNPs composed of a novel pH-sensitive lipid, a diversity of phospholipids and a highly-selective targeting peptide. A microfluidic device, iLiNP, was used and a variety of factors were controlled to tune particle size aiming at maximizing tumor penetration efficiency. Optimizing the composition and physico-chemical properties of the usLNPs resulted in an enhanced tumor accumulation, selectivity and in vivo gene silencing. The optimized usLNPs exerted potent gene silencing in the tumor (median effective dose, ED₅₀~0.1 mg/Kg) with limited effect on the healthy liver. The novel combination synergistically-eradicated HCC in mice (~85%) at a surprisingly-low dose of SOR (2.5 mg/Kg) which could not be achieved via individual monotherapy. Toxicity studies revealed the biosafety of the usLNPs upon either acute or chronic treatment. Furthermore, the SOR-resistant HCC established in mice was eradicated by 70% using this approach. We conclude that our strategy is promising for potential clinical applications in HCC treatment.

Chitosan-covered liposomes as a promising drug transporter: nanoscale investigations

Liposomes are small artificial vesicles spherical shaped of 50-1000 nm in diameter. They are created from natural non-toxic phospholipids membranes. Externally, they are decorated with biocompatible polymers. Chitosan, a natural polymer, demonstrates exceptional advantages in drug delivery, in particular, as liposome cover. In this paper, Molecular Dynamics simulations (MD) are performed in the coupled NPT-NPH and NVT-NVE statistical ensembles to study the static and dynamic properties of DPPC membrane-bilayer with grafted cationic chitosan chains, with added Cl- anions to neutralize the environment, using the Martini coarse-grained force-field. From the NPT-NPH MD simulations we found a chitosan layer L DM ranging from 3.2 to 6.6 nm for graft chains of a degree of polymerization n p = 45 and different grafting molar fractions X p = 0.005, X p = 0.014 and X p = 0.1. Also, the chitosan chains showed three essential grafting regimes: mushroom, critic, and brush depending on X p. The DPPC bilayer thickness D B and the area per lipid A l increased proportionally to X p. From the NVT-NVE MD simulations, the analysis of the radial distribution function showed that the increase of X p gives a more close-packed and rigid liposome. The analysis of the mean square displacement revealed that the diffusion of lipids is anomalous. In contrast, the diffusion of chitosan chains showed a normal diffusion, just after 100 ps. The diffusion regime of ions is found to be normal and independent of time. For the three identified regimes, the chitosan showed a tendency to adhere to the membrane surface and therefore affect the properties of the liposomal membrane.

Nanoapproaches to Modifying Epigenetics of Epithelial Mesenchymal Transition for Treatment of Pulmonary Fibrosis

Idiopathic Pulmonary Fibrosis (IPF) is a chronically progressive interstitial lung that affects over 3 M people worldwide and rising in incidence. With a median survival of 2-3 years, IPF is consequently associated with high morbidity, mortality, and healthcare burden. Although two antifibrotic therapies, pirfenidone and nintedanib, are approved for human use, these agents reduce the rate of decline of pulmonary function but are not curative and do not reverse established fibrosis. In this review, we discuss the prevailing epithelial injury hypothesis, wherein pathogenic airway epithelial cell-state changes known as Epithelial Mesenchymal Transition (EMT) promotes the expansion of myofibroblast populations. Myofibroblasts are principal components of extracellular matrix production that result in airspace loss and mortality. We review the epigenetic transition driving EMT, a process produced by changes in histone acetylation regulating mesenchymal gene expression programs. This mechanistic work has focused on the central role of bromodomain-containing protein 4 in mediating EMT and myofibroblast transition and initial preclinical work has provided evidence of efficacy. As nanomedicine presents a promising approach to enhancing the efficacy of such anti-IPF agents, we then focus on the state of nanomedicine formulations for inhalable delivery in the treatment of pulmonary diseases, including liposomes, polymeric nanoparticles (NPs), inorganic NPs, and exosomes. These nanoscale agents potentially provide unique properties to existing pulmonary therapeutics, including controlled release, reduced systemic toxicity, and combination delivery. NP-based approaches for pulmonary delivery thus offer substantial promise to modify epigenetic regulators of EMT and advance treatments for IPF.

Lipid Delivery Systems for Nucleic-Acid-Based-Drugs: From Production to Clinical Applications

In the last years the rapid development of Nucleic Acid Based Drugs (NABDs) to be used in gene therapy has had a great impact in the medical field, holding enormous promise, becoming “the latest generation medicine” with the first ever siRNA-lipid based formulation approved by the United States Food and Drug Administration (FDA) for human use, and currently on the market under the trade name Onpattro™. The growth of such powerful biologic therapeutics has gone hand in hand with the progress in delivery systems technology, which is absolutely required to improve their safety and effectiveness. Lipid carrier systems, particularly liposomes, have been proven to be the most suitable vehicles meeting NABDs requirements in the medical healthcare framework, limiting their toxicity, and ensuring their delivery and expression into the target tissues. In this review, after a description of the several kinds of liposomes structures and formulations used for in vitro or in vivo NABDs delivery, the broad range of siRNA-liposomes production techniques are discussed in the light of the latest technological progresses. Then, the current status of siRNA-lipid delivery systems in clinical trials is addressed, offering an updated overview on the clinical goals and the next challenges of this new class of therapeutics which will soon replace traditional drugs.

Disulfide phosphatidylcholines: alternative phospholipids for the preparation of functional liposomes

Disulfide phosphatidylcholine-based liposomes can be triggered and completely destroyed in a reductive tumor microenvironment resulting in a fast release of encapsulated drugs.