A Glycyrrhetinic Acid-Modified Curcumin Supramolecular Hydrogel for liver tumor targeting therapy

Glycyrrhetinic Acid as a Hepatocyte Targeting Ligand-Functionalized Platinum(IV) Complexes for Hepatocellular Carcinoma Therapy and Overcoming Multidrug Resistance

Promising targeted therapy options to overcome drug resistance and side effects caused by platinum(II) drugs for treatment in hepatocellular carcinoma are urgently needed. Herein, six novel multifunctional platinum(IV) complexes through linking platinum(II) agents and glycyrrhetinic acid (GA) were designed and synthesized. Among them, complex 20 showed superior antitumor activity against tested cancer cells including cisplatin resistance cells than cisplatin and simultaneously displayed good liver-targeting ability. Moreover, complex 20 can significantly cause DNA damage and mitochondrial dysfunction, promote reactive oxygen species generation, activate endoplasmic reticulum stress, and eventually induce apoptosis. Additionally, complex 20 can effectively inhibit cell migration and invasion and trigger autophagy and ferroptosis in HepG-2 cells. More importantly, complex 20 demonstrated stronger tumor inhibition ability than cisplatin or the combo of cisplatin/GA with almost no systemic toxicity in HepG-2 or A549 xenograft models. Collectively, complex 20 could be developed as a potential anti-HCC agent for cancer treatment.

Wondrous Yellow Molecule: Are Hydrogels a Successful Strategy to Overcome the Limitations of Curcumin?

Curcumin is a natural compound with a great pharmaceutical potential that involves anticancer, anti-inflammatory, antioxidant, and neuroprotective activity. Unfortunately, its low bioavailability, instability, and poor water solubility significantly deteriorate its clinical use. Many attempts have been made to overcome this issue, and encapsulating curcumin in a hydrogel matrix may improve those properties. Hydrogel formulation is used in many drug delivery forms, including classic types and novel forms such as self-assembly systems or responsive to external factors. Reviewed studies confirmed better properties of hydrogel-stabilized curcumin in comparison to pure compound. The main enhanced characteristics were chemical stability, bioavailability, and water solubility, which enabled these systems to be tested for various diseases. These formulations were evaluated for wound healing properties, effectiveness in treating skin diseases, and anticancer and regenerative activity. Hydrogel formulation significantly improved biopharmaceutical properties, opening the opportunity to finally see curcumin as a clinically approved substance and unravel its therapeutic potential.

Recent advances of novel targeted drug delivery systems based on natural medicine monomers against hepatocellular carcinoma

Hepatocellular carcinoma (HCC), the most prevalent type of liver cancer, is often diagnosed at an advanced stage. Surgical interventions are often ineffective, leading HCC patients to rely on systemic chemotherapy. Unfortunately, commonly used chemotherapeutic drugs have limited efficacy and can adversely affect vital organs, causing significant physical and psychological distress for patients. Natural medicine monomers (NMMs) have shown promising efficacy and safety profiles in HCC treatment, garnering attention from researchers. In recent years, the development of novel targeted drug delivery systems (TDDS) combining NMMs with nanocarriers has emerged. These TDDS aim to concentrate drugs effectively in HCC cells by manipulating the characteristics of nanomedicines, leveraging receptor and ligand interactions, and utilizing endogenous stimulatory responses to promote specific nanomedicines distribution. This comprehensive review presents recent research on TDDS for HCC treatment using NMMs from three perspectives: passive TDDS, active TDDS, and stimuli-responsive drug delivery systems (SDDS). It consolidates the current state of research on TDDS for HCC treatment with NMMs and highlights the potential of these innovative approaches in improving treatment outcomes. Moreover, the review also identifies research gaps in the related fields to provide references for future targeted therapy research in HCC.

Curcumin and analogues in mitigating liver injury and disease consequences: From molecular mechanisms to clinical perspectives

BACKGROUND

Liver injury is a prevalent global health concern, impacting a substantial number of individuals and leading to elevated mortality rates and socioeconomic burdens. Traditional primary treatment options encounter resource constraints and high costs, prompting exploration of alternative adjunct therapies, such as phytotherapy. Curcumin demonstrates significant therapeutic potential across various medical conditions, particularly emerging as a promising candidate for liver injury treatment.

PURPOSE

This study aims to provide current evidence maps of curcumin and its analogs in the context of liver injury, covering aspects of biosafety, toxicology, and clinical trials. Importantly, it seeks to summarize the intricate mechanisms modulated by curcumin.

METHODS

We conducted a comprehensive search of MEDLINE, Web of Science, and Embase up to July 2023. Titles and abstracts were reviewed to identify studies that met our eligibility criteria. The screening process involved three authors independently assessing the potential of curcumin mitigating liver injury and its disease consequences by reviewing titles, abstracts, and full texts.

RESULTS

Curcumin and its analogs have demonstrated low toxicity in vitro and in vivo. However, the limited bioavailability has hindered their advanced use in liver injury. This limitation can potentially be addressed by nano-curcumin and emerging drug delivery systems. Curcumin plays a role in alleviating liver injury by modulating the antioxidant system, as well as cellular and molecular pathways. The specific mechanisms involve multiple pathways, such as NF-κB, p38/MAPK, and JAK2/STAT3, and the pro-apoptosis Bcl-2/Bax/caspase-3 axis in damaged cells. Additionally, curcumin targets nutritional metabolism, regulating the substance in liver cells and tissues. The microenvironment associated with liver injury, like extracellular matrix and immune cells and factors, is also regulated by curcumin. Initial evaluation of curcumin and its analogs through 12 clinical trials demonstrates their potential application in liver injury.

CONCLUSION

Curcumin emerges as a promising phytomedicine for liver injury owing to its effectiveness in hepatoprotection and low toxicity profile. Nevertheless, in-depth investigations are warranted to unravel the complex mechanisms through which curcumin influences liver tissues and overall physiological milieu. Moreover, extensive clinical trials are essential to determine optimal curcumin dosage forms, maximizing its benefits and achieving favorable clinical outcomes.

Use of pyridazinediones for tuneable and reversible covalent cysteine modification applied to peptides, proteins and hydrogels

Reversible cysteine modification has been found to be a useful tool for a plethora of applications such as selective enzymatic inhibition, activity-based protein profiling and/or cargo release from a protein or a material. However, only a limited number of reagents display reliable dynamic/reversible thiol modification and, in most cases, many of these reagents suffer from issues of stability, a lack of modularity and/or poor rate tunability. In this work, we demonstrate the potential of pyridazinediones as novel reversible and tuneable covalent cysteine modifiers. We show that the electrophilicity of pyridazinediones correlates to the rates of the Michael addition and retro-Michael deconjugation reactions, demonstrating that pyridazinediones provide an enticing platform for readily tuneable and reversible thiol addition/release. We explore the regioselectivity of the novel reaction and unveil the reason for the fundamental increased reactivity of aryl bearing pyridazinediones by using DFT calculations and corroborating findings with SCXRD. We also applied this fundamental discovery to making more rapid disulfide rebridging agents in related work. We finally provide the groundwork for potential applications in various areas with exemplification using readily functionalised "clickable" pyridazinediones on clinically relevant cysteine and disulfide conjugated proteins, as well as on a hydrogel material.

Recent Advances in Anticancer Activity of Novel Plant Extracts and Compounds from Curcuma longa in Hepatocellular Carcinoma

PURPOSE

Among all forms of cancers, hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide. There are several treatment options for HCC ranging from loco-regional therapy to surgical treatment. Yet, there is high morbidity and mortality. Recent research focus has shifted towards more effective and less toxic cancer treatment options. Curcumin, the active ingredient in the Curcuma longa plant, has gained widespread attention in recent years because of its multifunctional properties as an antioxidant, anti-inflammatory, antimicrobial, and anticancer agent.

METHODS

A systematic search of PubMed, Embase and Google Scholar was performed for studies reporting incidence of HCC, risk factors associated with cirrhosis and experimental use of curcumin as an anti-cancer agent.

RESULTS

This review exclusively encompasses the anti-cancer properties of curcumin in HCC globally and it's postulated molecular targets of curcumin when used against liver cancers.

CONCLUSIONS

This review is concluded by presenting the current challenges and future perspectives of novel plant extracts derived from C. longa and the treatment options against cancers.

Unification of medicines and excipients: The roles of natural excipients for promoting drug delivery

INTRODUCTION

Drug delivery systems (DDSs) formed by natural active compounds be instrumental in developing new green excipients and novel DDS from natural active compounds (NACs). 'Unification of medicines and excipients'(UME), the special inherent nature of the natural active compounds, provides the inspiration and conduction to achieve this goal.

AREAS COVERED

This review summarizes the typical types of NACs from herbal medicine, such as saponins, flavonoids, polysaccharides, etc. that act as excipients and their main application in DDS. The comparison of the drug delivery systems formed by NACs and common materials and the primary formation mechanisms of these NACs are also introduced to provide a deepened understanding of their performance in DDS.

EXPERT OPINION

Many natural bioactive compounds, such as saponins, polysaccharides, etc. have been used in DDS. Diversity of structure and pharmacological effects of NACs turn out the unique advantages in improving the performance of DDSs like targeting ability, adhesion, encapsulation efficiency(EE), etc. and enhancing the bioavailability of loaded drugs.

Curcumin-loaded alginate hydrogels for cancer therapy and wound healing applications: A review

Hydrogels have emerged as a versatile platform for a numerous biomedical application due to their ability to absorb a huge quantity of biofluids. In order to design hydrogels, natural polymers are an attractive option owing to their biocompatibility and biodegradability. Due to abundance in occurrence, cost effectiveness, and facile crosslinking approaches, alginate has been extensively investigated to fabricate hydrogel matrix. Management of cancer and chronic wounds have always been a challenge for pharmaceutical and healthcare sector. In both cases, curcumin have been shown significant improvement and effectiveness. However, the innate restraints like poor bioavailability, hydrophobicity, and rapid systemic clearance associated with curcumin have restricted its clinical translations. The current review explores the cascade of research around curcumin encapsulated alginate hydrogel matrix for wound healing and cancer therapy. The focus of the review is to emphasize the mechanistic effects of curcumin with its fate inside the cells. Further, the review discusses different approaches to designed curcumin loaded alginate hydrogels along with the parameters that regulates their release behavior. Finally, the review is concluded with emphasize on some key aspect on increasing the efficacy of these hydrogels along with novel strategies to further develop curcumin loaded alginate hydrogel matrix with multifacet applications.

Next-Generation Hydrogels as Biomaterials for Biomedical Applications: Exploring the Role of Curcumin

Since the first report on the pharmacological activity of curcumin in 1949, enormous amounts of research have reported diverse activities for this natural polyphenol found in the dietary spice turmeric. However, curcumin has not yet been used for human application as an approved drug. The clinical translation of curcumin has been hampered due to its low solubility and bioavailability. The improvement in bioavailability and solubility of curcumin can be achieved by its formulation using drug delivery systems. Hydrogels with their biocompatibility and low toxicity effects have shown a substantial impact on the successful formulation of hydrophobic drugs for human clinical trials. This review focuses on hydrogel-based delivery systems for curcumin and describes its applications as anti-cancer as well as wound healing agents.

Functional System Based on Glycyrrhizic Acid Supramolecular Hydrogel: Toward Polymorph Control, Stabilization, and Controlled Release

Developments of a drug delivery system (DDS) based on a natural supramolecular hydrogel have been of wide interest due to its biocompatibility, efficacy, and adjustable performance. However, a simple and efficient design of functional hydrogel DDS based on the templated interplay of gelator and model drug is still a challenge. In this work, natural glycyrrhetinic acid (GA) gel was selected as a carrier to encapsulate the model drug pyrazinamide (PZA). It was found that the carboxyl-amide interaction at the interface of gel-drug achieved polymorph control, stabilization, and pH-responsive release. Powder X-ray diffraction confirmed that the metastable γ form of PZA was obtained from the GA gel. Spectral analysis and molecular dynamics simulation showed that the protonation at the amide-O promoted the discretization of PZA molecules in solution, resulting in the polymorphism. Furthermore, the gel-drug interplay increased the stability of the γ form significantly from 2 days to 3 months by in situ encapsulation in the GA gel. In vitro release study indicated that the GA gel achieved targeted control release of PZA due to the pH-responsiveness property of GA. This work provides a promising option for hydrogel-based DDS design combined with polymorph control and stabilization.

Intracellular Formation of Hemicyanine Nanoparticle Enhances Tumor-Targeting Photoacoustic Imaging and Photothermal Therapy

Alkaline phosphatase (ALP) is a tumor marker for early diagnosis and treatment. Tumor targeting can recognize and fight tumor cells more accurately from healthy cells. Glycyrrhetinic acid (GA) is a targeting ligand of liver tumors. Photoacoustic imaging (PAI) and photothermal therapy (PTT) are promising techniques for tumor diagnosis and treatment. The outstanding characteristics of Hemicyanine (HCy) dye make it suitable for tumor diagnosis and treatment. However, using HCy nanoparticle (HCy NP) for liver tumor-targeting PAI and PTT has not been reported. Herein, Probe-1 is developed to enhance PAI and PTT of liver tumors due to GA targeting and intracellular ALP-instructed self-assembly of HCy NP. Compared to Probe-2 without self-assembly ability, Probe-1 displays a 4.6-fold higher PAI signal or 1.7-fold lower half inhibitory concentrations in HepG2 cells. Moreover, Probe-1 shows extended retention time (10 vs 6 h) and 2.1-fold higher PAI signal than Probe-2 in HepG2 tumors. The HepG2 tumors in Group Probe-1 obviously increase 18 °C (T_max : 55 °C) with a 3.3-fold decreased volume while that in Group Probe-2 mildly increase 9.8 °C (T_max : 46.8 °C) with a 4.3-fold increased volume. It is envisioned that this smart self-assembly strategy can be easily adjusted for PAI and PTT of more tumors.

Self-assembled glycyrrhetinic acid derivatives for functional applications: a review

Glycyrrhetinic acid (GA), a famous natural product, has been attracting more attention recently because of its remarkable biological activity, natural sweetness, and good biocompatibility. In the past few years, a considerable amount of literature has grown up around the theme of GA-based chemical modification to broaden its functional applications. Promising structures including gels, micelles, nanoparticles, liposomes, and so forth have been constantly reported. On the one hand, the assembly mechanisms of various materials based on GA derivatives have been elucidated via modern analytical techniques. On the other hand, their potential application prospects in edible additives, intelligent drug delivery, and other fields have been investigated fully due to availability, biocompatibility, and controllable degradability. Inspired by these findings, a systematic summary and classification of the materials formed by GA derivatives seems necessary and meaningful. This review sums up the new functional applications of GA derivatives for the first time and provides better prospects for their application and development.

Edible pentacyclic triterpenes: A review of their sources, bioactivities, bioavailability, self-assembly behavior, and emerging applications as functional delivery vehicles

Edible pentacyclic triterpenes (PTs) are a group of nutraceutical ingredients commonly distributed in human diets. Existing evidence has proven that they have various biological functions, including anticancer, antioxidant, anti-inflammatory and hypoglycemic activities, making them as "functional factor" for a long time. However, their properties of strong hydrophobicity, poor permeability, poor absorption, and rapid metabolism result in low oral bioavailability, which dramatically hinders their efficacy for use. Recently, free PTs have successively been found to self-assemble or co-assemble into self-contained nanostructures with enhanced water dispersibility and oral bioavailability, which seems to be an efficient processing method for increased oral efficacy. Of particular interest, formulating them into nanostructures can also be introduced as functional delivery carriers for bioactive compounds or drugs with various advantages, such as improved stability, controlled release, enhanced oral bioavailability, synergistic bioactivity, and targeted delivery. This review systematically summarized the chemical structures, plant sources, bioactivities, absorption, metabolism, and oral bioavailability of PTs. Notably, we emphasized their self-assembly properties and emerging role as functional delivery carriers for nutrients, suggesting that PT nanostructures are not only efficient oral forms when introduced into foods but also functional delivery materials for nutrients to expand their commercial food applications.

Licorice (Glycyrrhiza glabra L.)-Derived Phytochemicals Target Multiple Signaling Pathways to Confer Oncopreventive and Oncotherapeutic Effects

Cancer is a highly lethal disease, and its incidence has rapidly increased worldwide over the past few decades. Although chemotherapeutics and surgery are widely used in clinical settings, they are often insufficient to provide the cure for cancer patients. Hence, more effective treatment options are highly needed. Although licorice has been used as a medicinal herb since ancient times, the knowledge about molecular mechanisms behind its diverse bioactivities is still rather new. In this review article, different anticancer properties (antiproliferative, antiangiogenic, antimetastatic, antioxidant, and anti-inflammatory effects) of various bioactive constituents of licorice (Glycyrrhiza glabra L.) are thoroughly described. Multiple licorice constituents have been shown to bind to and inhibit the activities of various cellular targets, including B-cell lymphoma 2, cyclin-dependent kinase 2, phosphatidylinositol 3-kinase, c-Jun N-terminal kinases, mammalian target of rapamycin, nuclear factor-κB, signal transducer and activator of transcription 3, vascular endothelial growth factor, and matrix metalloproteinase-3, resulting in reduced carcinogenesis in several in vitro and in vivo models with no evident toxicity. Emerging evidence is bringing forth licorice as an anticancer agent as well as bottlenecks in its potential clinical application. It is expected that overcoming toxicity-related obstacles by using novel nanotechnological methods might importantly facilitate the use of anticancer properties of licorice-derived phytochemicals in the future. Therefore, anticancer studies with licorice components must be continued. Overall, licorice could be a natural alternative to the present medication for eradicating new emergent illnesses while having just minor side effects.

A Comprehensive Review on Liver Targeting: Emphasis on Nanotechnology- based Molecular Targets and Receptors Mediated Approaches

BACKGROUND

The pathogenesis of hepatic diseases involves several cells, which complicates the delivery of pharmaceutical agents. Many severe liver diseases affecting the worldwide population cannot be effectively treated. Major hindrances or challenges are natural physiological barriers and non-specific targeting of drugs administered, leading to inefficient treatment. Hence, there is an earnest need to look for novel therapeutic strategies to overcome these hindrances. A kind of literature has reported that drug safety and efficacy are incredibly raised when a drug is incorporated inside or attached to a polymeric material of either hydrophilic or lipophilic nature. This has driven the dynamic investigation for developing novel biodegradable materials, drug delivery carriers, target-specific drug delivery systems, and many other novel approaches.

OBJECTIVE

Present review is devoted to summarizing receptor-based liver cell targeting using different modified novel synthetic drug delivery carriers. It also highlights recent progress in drug targeting to diseased liver mediated by various receptors, including asialoglycoprotein, mannose and galactose receptor, Fc receptor, low-density lipoprotein, glycyrrhetinic, and bile acid receptor. The essential consideration is given to treating liver cancer targeting using nanoparticulate systems, proteins, viral and non-viral vectors, homing peptides and gene delivery.

CONCLUSION

Receptors based targeting approach is one such approach that was explored by researchers to develop novel formulations which can ensure site-specific drug delivery. Several receptors are on the surfaces of liver cells, which are highly overexpressed in various disease conditions. They all are helpful for the treatment of liver cancer.

Injectable Carrier-Free Hydrogel Dressing with Anti-Multidrug-Resistant Staphylococcus aureus and Anti-Inflammatory Capabilities for Accelerated Wound Healing

Antibacterial hydrogels have gradually become a powerful weapon to treat bacterially infected wounds and accelerate healing. In this paper, we designed a small-molecule self-healing antibacterial hydrogel containing 100% drug-loaded benzyl 3β-amino-11-oxo-olean-12-en-30-oate (GN-Bn), which was governed by π-π stacking, hydrogen bonding, and van der Waals forces. Due to the carrier-free design concept, the problems of interbatch variability during sample preparation and carrier-related toxicity can be effectively avoided. Moreover, the GN-Bn hydrogel exhibited promising antibacterial activities against multidrug-resistant Staphylococcus aureus (MRSA). The minimum inhibitory concentration (MIC) of the GN-Bn hydrogel was 1.5625 nmol/mL, which was lower than those against clinical agents such as norfloxacin, penicillin, and tetracycline. This is attributed to its unique antibacterial mechanism that aims at killing bacteria or preventing their growth by regulating arginine biosynthesis and metabolism through both transcriptomic (RNA-seq) analysis and quantitative polymerase chain reaction (qPCR) analysis. In addition, the GN-Bn hydrogel can also inhibit proinflammatory cytokines (TNF-α, IL-1β, and IL-6) to promote wound healing. Collectively, the GN-Bn hydrogel elicited dual therapeutic effects on an MRSA-infected full-thickness skin wound model through its antibacterial and anti-inflammatory activities, which is attributed to the fact that the GN-Bn hydrogel has multiple advantages including sufficient mechanical stability, biocompatibility, and unique antibacterial mechanisms, making it significantly accelerate MRSA-infected full-thickness skin wound healing as a wound dressing. In a word, the GN-Bn antibacterial hydrogel dressing with an anti-inflammatory and antibacterial bifunctional material holds great potential in clinical application.

A Comprehensive Review of Cross-Linked Gels as Vehicles for Drug Delivery to Treat Central Nervous System Disorders

Gels are attractive candidates for drug delivery because they are easily producible while offering sustained and/or controlled drug release through various mechanisms by releasing the therapeutic agent at the site of action or absorption. Gels can be classified based on various characteristics including the nature of solvents used during preparation and the method of cross-linking. The development of novel gel systems for local or systemic drug delivery in a sustained, controlled, and targetable manner has been at the epitome of recent advances in drug delivery systems. Cross-linked gels can be modified by altering their polymer composition and content for pharmaceutical and biomedical applications. These modifications have resulted in the development of stimuli-responsive and functionalized dosage forms that offer many advantages for effective dosing of drugs for Central Nervous System (CNS) conditions. In this review, the literature concerning recent advances in cross-linked gels for drug delivery to the CNS are explored. Injectable and non-injectable formulations intended for the treatment of diseases of the CNS together with the impact of recent advances in cross-linked gels on studies involving CNS drug delivery are discussed.

Hydrogels for localized chemotherapy of liver cancer: a possible strategy for improved and safe liver cancer treatment

The systemic drug has historically been preferred for the treatment of the majority of pathological conditions, particularly liver cancer. Indeed, this mode of treatment is associated with adverse reactions, toxicity, off-target accumulation, and rapid hepatic and renal clearance. Numerous efforts have been made to design systemic therapeutic carriers to improve retention while decreasing side effects and clearance. Following systemic medication, local administration of therapeutic agents allows for higher 'effective' doses with fewer side effects, kidney accumulation, and clearance. Hydrogels are highly biocompatible and can be used for both imaging and therapy. Hydrogel-based drug delivery approach has fewer side effects than traditional chemotherapy and can deliver drugs to tumors for a longer time. The chemical and physical flexibility of hydrogels can be used to achieve disease-induced in situ accumulation as well as subsequent drug release and hydrogel-programmed degradation. Moreover, they can act as a biocompatible depot for localized chemotherapy when stimuli-responsive carriers are administrated. Herein, we summarize the design strategies of various hydrogels used for localized chemotherapy of liver cancer and their delivery routes, as well as recent research on smart hydrogels.

Recent advances in glycyrrhizin metabolism, health benefits, clinical effects and drug delivery systems for efficacy improvement; a comprehensive review

BACKGROUND

Glycyrrhizin (GL) is a major active constituent of licorice root (Glycyrrhiza glabra) that is considered one of the oldest and most frequently employed botanicals in Chinese medicine and worldwide, with most effects attributed to its rich GL content. Structurally, GL a triterpene saponin that is widely used as a flavoring agent in foodstuffs and cosmetics, and also proposed for various clinical applications with a myriad of health benefits. Pharmacological and biological activities of GL include antiviral, anti-inflammatory, antioxidant, and anticancer activities (in vitro and in vivo). Currently, there is no comprehensive review on GL biological effects and its action mechanisms.

PURPOSE

This review summarizes GL pharmacological actions from a molecular biology perception, presented on its metabolism and side effects based on in vitro, in vitro and clinical studies. Moreover, the potential of GL as a nanomedicine delivery system is also summarized. The progress in drug delivery research using GL presented herein is expected to provide a theoretical basis for developing other novel drugs formulations.

METHODS

A systematic review was carried out in several electronic databases (Science Direct, SpringerLink, CNKI, PubMed, Web of Science, Elsevier, and Scopus), using the following key words: glycyrrhizin "AND" bioactivity "OR" clinic "OR" therapeutic "OR" drug delivery. This search included manuscripts published between 1989 and 2021.

RESULTS

126 researches were selected and summarized in this review. The analysis of these studies indicated that GL has antiviral activity against different viruses. Further, GL efficiently suppressed the respiratory manifestations associated with COVID-19 by reducing the expression of angiotensin converting enzyme 2 (ACE2) that employed by the virus as an entry point. Otherwise, GL was found to induce antioxidant, anti-inflammatory, immune-modulatory, and anticancer activity. Besides, diminution the particle size of GL to nanometer size significantly augments their action and biodistribution.

CONCLUSION

This article summarizes the pharmacological actions of GL. The potential of GL as a nanomedicine delivery system is also presented. Nevertheless, most studies reported provide no deep insight of GL health effects warranting for more future studies to elucidate its action mechanism and potential therapeutic benefits through preclinical and clinical trials.

Glycyrrhizic Acid and Its Hydrolyzed Metabolite 18β-Glycyrrhetinic Acid as Specific Ligands for Targeting Nanosystems in the Treatment of Liver Cancer

Glycyrrhizic acid and its hydrolyzed metabolite 18β-glycyrrhetinic acid, obtained from the plant Glycyrrhiza glabra, have numerous pharmacological activities, such as anti-inflammatory, anti-ulcerative, antiallergic, immunomodulatory, antiviral, antitumor, hepatoprotective, and antioxidant effects, and others. In addition to the pharmacological activities, in the 1980s, an interaction and uptake of these molecules by the liver was verified, which was later confirmed by other studies through the discovery of specific receptors in the hepatocytes. The presence of these specific receptors in the liver led to vectorization and delivery of drugs, by the introduction of glycyrrhizic acid or glycyrrhetinic acid on the surface of nanosystems, for the treatment of liver diseases. This review describes experimental evidence of vectorization by conjugating glycyrrhizic acid or glycyrrhetinic acid to nanosystems and delivery of antitumor drugs for the treatment of liver cancer and also describes the techniques used to perform this conjugation. We have shown that due to the existence of specific receptors for these molecules, in addition to the targeting of nanosystems to hepatocytes, nanosystems having glycyrrhizic acid or glycyrrhetinic acid on their surface had the same therapeutic effect in a significantly lower dose compared to the free drug and unconjugated nanosystems, with consequent reduction of side effects and toxicity.

Development of Natural-Drugs-Based Low-Molecular-Weight Supramolecular Gels

Natural small molecular drugs with excellent biocompatibility, diverse pharmacological activities, and wide sources play an increasingly important role in the development of new drug and disease treatment. In recent years, the utilization of paclitaxel, camptothecin, rhein, curcumin, and other natural small molecular drugs with unique rigid backbone structures and modifiable multiple sites as building blocks to form gels by self-assembly has attracted widespread attention. The obtained low-molecular-weight supramolecular gel not only retains the general characteristics of the gel but also overcomes the shortcomings of natural drugs, such as poor water solubility and low bioavailability. It has the advantages of high drug loading, low toxicity, and outstanding stimulus responsiveness, which is widely used in biomedical fields. Here, we provided a comprehensive review of natural-drugs-based low-molecular-weight supramolecular gels reported in recent years and summarized their assembly mechanism, gel structure, gel properties, and potential applications. It is expected to provide a reference for further research of natural-drugs-based supramolecular gels.

A review of existing strategies for designing long-acting parenteral formulations: Focus on underlying mechanisms, and future perspectives

The need for long-term treatments of chronic diseases has motivated the widespread development of long-acting parenteral formulations (LAPFs) with the aim of improving drug pharmacokinetics and therapeutic efficacy. LAPFs have been proven to extend the half-life of therapeutics, as well as to improve patient adherence; consequently, this enhances the outcome of therapy positively. Over past decades, considerable progress has been made in designing effective LAPFs in both preclinical and clinical settings. Here we review the latest advances of LAPFs in preclinical and clinical stages, focusing on the strategies and underlying mechanisms for achieving long acting. Existing strategies are classified into manipulation of in vivo clearance and manipulation of drug release from delivery systems, respectively. And the current challenges and prospects of each strategy are discussed. In addition, we also briefly discuss the design principles of LAPFs and provide future perspectives of the rational design of more effective LAPFs for their further clinical translation.

From Supramolecular Hydrogels to Multifunctional Carriers for Biologically Active Substances

Supramolecular hydrogels are 3D, elastic, water-swelled materials that are held together by reversible, non-covalent interactions, such as hydrogen bonds, hydrophobic, ionic, host-guest interactions, and metal-ligand coordination. These interactions determine the hydrogels' unique properties: mechanical strength; stretchability; injectability; ability to self-heal; shear-thinning; and sensitivity to stimuli, e.g., pH, temperature, the presence of ions, and other chemical substances. For this reason, supramolecular hydrogels have attracted considerable attention as carriers for active substance delivery systems. In this paper, we focused on the various types of non-covalent interactions. The hydrogen bonds, hydrophobic, ionic, coordination, and host-guest interactions between hydrogel components have been described. We also provided an overview of the recent studies on supramolecular hydrogel applications, such as cancer therapy, anti-inflammatory gels, antimicrobial activity, controlled gene drug delivery, and tissue engineering.

Glycyrrhetinic Acid and TAT Peptide Modified Dual-functional Liposomes for Treatment of Hepatocellular Cancer

BACKGROUND

Surgery remains the front-line therapeutic strategy to treat early hepatocellular carcinoma (HCC). However, the 5-year recurrence rates of HCC patients are high. 10- Hydroxycamptothecin (10-HCPT) is a known anti-HCC agent but its poor solubility and bioavailability have limited its clinical use.

OBJECTIVE

In this study, we developed a novel nanoliposome encapsulated 10-hydroxycamptothecin modified with glycyrrhetinic acid (GA) and TAT peptide (GA/TAT-HCPT-LP) for the treatment of HCC. Dual modified GA and TAT can enhance tumor targeting and tumor penetration.

METHODS

The GA/TAT-HCPT-LP NPs were synthesized using the thin-film dispersion method. GA/TAT-HCPT-LP were characterized for particle size, zeta potential and morphology. Drug release from the GA/TAT-HCPT-LP liposomes was measured by dialysis. Cell-uptake was assessed by microscopy and flow cytometry. Cell proliferation, migration and apoptosis were measured to evaluate in vitro antitumor activity of GA/TAT-HCPT-LP via CCK-8 assays, Transwell assays, and flow cytometry, respectively. The in vivo distribution of GA/TAT-HCPT-LP was evaluated in HCC animal models. Tumor- bearing mouse models were used to assess the in vivo therapeutic efficacy of GA/TAT-HCPT-LP.

RESULTS

The mean particle size and mean zeta potential of GA/TAT-HCPT-LP were 135.55 ± 2.76 nm and -4.57 ± 0.23 mV, respectively. Transmission electron micrographs (TEM) showed that the GA/TAT-HCPT-LP had a near spherical shape and a double-membrane structure. GA/TAT-HCPT-LP led to slow and continuous drug release, and could bind to HepG2 cells more readily than other groups. Compared to control groups, treatment with GA/TAT-HCPT-LP had a significantly large effect on inhibiting cell proliferation, tumor cell migration and cell apoptosis. In vivo assays showed that GA/TATHCPT- LP selectively accumulated in tumor tissue with obvious antitumor efficacy.

CONCLUSION

In conclusion, the synthesized GA/TAT-HCPT-LP could effectively target tumor cells and enhance cell penetration, highlighting its potential for hepatocellular cancer therapy.

Recent Advances in Asialoglycoprotein Receptor and Glycyrrhetinic Acid Receptor-Mediated and/or pH-Responsive Hepatocellular Carcinoma- Targeted Drug Delivery

BACKGROUND

Hepatocellular carcinoma (HCC) seriously affects human health, especially, it easily develops multi-drug resistance (MDR) which results in treatment failure. There is an urgent need to develop highly effective and low-toxicity therapeutic agents to treat HCC and to overcome its MDR. Targeted drug delivery systems (DDS) for cancer therapy, including nanoparticles, lipids, micelles and liposomes, have been studied for decades. Recently, more attention has been paid to multifunctional DDS containing various ligands such as polymer moieties, targeting moieties, and acid-labile linkages. The polymer moieties such as poly(ethylene glycol) (PEG), chitosan (CTS), hyaluronic acid, pullulan, poly(ethylene oxide) (PEO), poly(propylene oxide) (PPO) protect DDS from degradation. Asialoglycoprotein receptor (ASGPR) and glycyrrhetinic acid receptor (GAR) are most often used as the targeting moieties, which are overexpressed on hepatocytes. Acid-labile linkage, catering for the pH difference between tumor cells and normal tissue, has been utilized to release drugs at tumor tissue.

OBJECTIVES

This review provides a summary of the recent progress in ASGPR and GAR-mediated and/or pH-responsive HCC-targeted drug delivery.

CONCLUSION

The multifunctional DDS may prolong systemic circulation, continuously release drugs, increase the accumulation of drugs at the targeted site, enhance the anticancer effect, and reduce side effects both in vitro and in vivo. But it is rarely used to investigate MDR of HCC; therefore, it needs to be further studied before going into clinical trials.

Nanotechnology Based Approach for Hepatocellular Carcinoma Targeting

Hepatocellular carcinoma (HCC) is the primary liver cancer that has shown a high incidence and mortality rate worldwide among several types of cancers. A large variety of chemotherapeutic agents employed for the treatment have a limited success rate owing to their limited site-specific drug targeting ability. Thus, there is a demand to develop novel approaches for the treatment of HCC. With advancements in nanotechnology-based drug delivery approaches, the challenges of conventional chemotherapy have been continuously decreasing. Nanomedicines constituted of lipidic and polymeric composites provide a better platform for delivering and opening new pathways for HCC treatment. A score of nanocarriers such as surface-engineered liposomes, nanoparticles, nanotubes, micelles, quantum dots, etc., has been investigated in the treatment of HCC. These nanocarriers are considered to be highly effective clinically for delivering chemotherapeutic drugs with high site-specificity ability and therapeutic efficiency. The present review highlights the current focus on the application of nanocarrier systems using various ligand-based receptor-specific targeting strategies for the treatment and management of HCC. Moreover, the article has also included information on the current clinically approved drug therapy for hepatocellular carcinoma treatment and updates of regulatory requirements for approval of such nanomedicines.

Research progress on the protective effects of licorice-derived 18β-glycyrrhetinic acid against liver injury

The first description of the medical use of licorice appeared in "Shennong Bencao Jing", one of the well-known Chinese herbal medicine classic books dated back to 220-280 AD. As one of the most commonly prescribed Chinese herbal medicine, licorice is known as "Guo Lao", meaning "a national treasure" in China. Modern pharmacological investigations have confirmed that licorice possesses a number of biological activities, such as antioxidation, anti-inflammatory, antiviral, immune regulation, and liver protection. 18β-glycyrrhetinic acid is one of the most extensively studied active integrants of licorice. Here, we provide an overview of the protective effects of 18β-glycyrrhetinic acid against various acute and chronic liver diseases observed in experimental models, and summarize its pharmacological effects and potential toxic/side effects at higher doses. We also make additional comments on the important areas that may warrant further research to support appropriate clinical applications of 18β-glycyrrhetinic acid and avoid potential risks.

Advances in self-assembled injectable hydrogels for cancer therapy

Non-specific toxicity of chemotherapeutics and evolution of malignant tumors against them are major challenges for existing cancer chemotherapeutic regimens. Engineering of nanomaterials has attempted to minimize the toxicity of anticancer drugs, but systemic delivery of these nanomaterials still imposes many hurdles in their clinical use like burst release of chemotherapeutics and toxicity and immunogenicity associated with excipients of nanomaterials. However, there has been a surge in the development of natural and synthetic nanomaterials to deliver anticancer agents to the diseased (tumor) site as it can minimize the systemic circulation of anticancer drugs and reduce the toxicity-related challenges. Therefore, localized drug delivery is considered as the most effective way to deliver therapeutics but is further challenged by poor biodegradability, high immunogenicity, poor drug entrapment efficacy and inability to maintain sustained release of anticancer agents at the tumor site. This review maps out recent advancements in engineering of low molecular weight hydrogels derived from amino acid, fatty acyl, steroidal lipid and drug conjugated amphiphilic scaffolds. We have summarized the efforts for the development of molecular hydrogels in terms of biocompatibility, therapeutic potential and challenges associated with existing molecular hydrogels for cancer therapy.

Self-assembling Peptides in Current Nanomedicine: Versatile Nanomaterials for Drug Delivery

BACKGROUND

The development of modern nanomedicine greatly depends on the involvement of novel materials as drug delivery system. In order to maximize the therapeutic effects of drugs and minimize their side effects, a number of natural or synthetic materials have been widely investigated for drug delivery. Among these materials, biomimetic self-assembling peptides (SAPs) have received more attention in recent years. Considering the rapidly growing number of SAPs designed for drug delivery, a summary of how SAPs-based drug delivery systems were designed, would be beneficial.

METHOD

We outlined research works on different SAPs that have been investigated as carriers for different drugs, focusing on the design of SAPs nanomaterials and how they were used for drug delivery in different strategies.

RESULTS

Based on the principle rules of chemical complementarity and structural compatibility, SAPs such as ionic self-complementary peptide, peptide amphiphile and surfactant-like peptide could be designed. Determined by the features of peptide materials and the drugs to be delivered, different strategies such as hydrogel embedding, hydrophobic interaction, electrostatic interaction, covalent conjugation or the combination of them could be employed to fabricate SAPs-drug complex, which could achieve slow release, targeted or environment-responsive delivery of drugs. Furthermore, some SAPs could also be combined with other types of materials for drug delivery, or even act as drug by themselves.

CONCLUSION

Various types of SAPs have been designed and used for drug delivery following various strategies, suggesting that SAPs as a category of versatile nanomaterials have promising potential in the field of nanomedicine.

A Novel Fabrication of Dose-Dependent Injectable Curcumin Biocomposite Hydrogel System Anesthetic Delivery Method for Care and Management of Musculoskeletal Pain

Chronic musculoskeletal pain has biological, psychological, and social components. In this article, we have demonstrated the easily injectable nanocomposite carrier for the treatment of chronic musculoskeletal pain. Briefly, the curcumin (Cur) loaded with lipid nanocapsules (LNCs; Cur@LNCs) using the phase invasion method. The synthesized Cur@LNCs were characterized by using scanning electron microscopy, transmittance electron microscopy, and the size of the fabricated nanoparticles confirmed by dynamic light scattering analysis. The synthesized Cur@LNC injectable hydrogel shows excellent results in vivo in the rat model. We have examined the efficiency of the chronic constriction injury in the rat model and induced the pain using thermal paw withdrawal latency. The injectable hydrogels Cur@LNCs display a remarkable reduction in pain 7 days post administrations compared to the untreated group animals. This work could establish the preclinical candidate of the neuropathic pain response in the future.

Mimicking tumor hypoxia and tumor-immune interactions employing three-dimensional in vitro models

The heterogeneous tumor microenvironment (TME) is highly complex and not entirely understood. These complex configurations lead to the generation of oxygen-deprived conditions within the tumor niche, which modulate several intrinsic TME elements to promote immunosuppressive outcomes. Decoding these communications is necessary for designing effective therapeutic strategies that can effectively reduce tumor-associated chemotherapy resistance by employing the inherent potential of the immune system.While classic two-dimensional in vitro research models reveal critical hypoxia-driven biochemical cues, three-dimensional (3D) cell culture models more accurately replicate the TME-immune manifestations. In this study, we review various 3D cell culture models currently being utilized to foster an oxygen-deprived TME, those that assess the dynamics associated with TME-immune cell penetrability within the tumor-like spatial structure, and discuss state of the art 3D systems that attempt recreating hypoxia-driven TME-immune outcomes. We also highlight the importance of integrating various hallmarks, which collectively might influence the functionality of these 3D models.This review strives to supplement perspectives to the quickly-evolving discipline that endeavors to mimic tumor hypoxia and tumor-immune interactions using 3D in vitro models.

Puerarin-loaded ultrasound microbubble contrast agent used as sonodynamic therapy for diabetic cardiomyopathy rats

In this study, a puerarin-loaded ultrasound sulfur hexafluoride microbubble contrast agent as a sonodynamic therapy (SDT) was developed to improve targeted drug delivery and pharmacodynamic effects in diabetic cardiomyopathy (DCM) treatment. Fluorescence microscope morphology was applied to confirm the fabrication of the puerarin - microbubbles (PMBs). The average size distribution and zeta potential of PMBs were 760.0 ± 101.2 nm and -20.4 ± 6.59 mV, respectively. In vitro and in vivo experiments were carried out to study the pharmacodynamic effects and targeted drug delivery of PMBs. The cytotoxicity, assessed by the cell viability of human umbilical vein endothelial cells (HUVECs), showed that the microbubbles were nontoxic even in high concentration of 2.500 mg/mL, and the wound healing scratch assay proved that PMBs cloud obviously improve the migration ability of HUVECs. Furthermore, streptozotocin (STZ) accompanied with high-energy diets was employed to build the DCM rat model. The blood glucose, histological changes of the pancreas and heart, and cardiac function were used to confirm the obtainment of the DCM rat model. Histological and physiological changes of the PMBs treatment group indicated that PMBs had a significant therapeutic efficacy when compared to the DCM model group. Therefore, PMBs are a promising strategy for a targeted drug delivery system and a novel noninvasive treatment for DCM.

Enzyme-Instructed Self-Assembly for Cancer Therapy and Imaging

Enzymatic reactions and self-assembly are two fundamental attributes of cells. It is not surprising that one can use enzyme-instructed self-assembly (EISA)-the integration of enzymatic transformation and molecular self-assembly-to modulate the emergent properties of supramolecular assemblies for controlling cell behaviors. The exploration of EISA for developing cancer therapy and imaging has made considerable progress over the last five years. In this Topical Review, we discuss these exciting results and the future promise of EISA. After describing several key studies to illustrate the progress of EISA in developing cancer therapy, we discuss the use of EISA for molecular imaging. Then, we give the outlook of EISA for developing supramolecular anticancer medicine that inhibits multiple hallmark capabilities of cancer.

Glycyrrhetinic acid-modified graphene oxide mediated siRNA delivery for enhanced liver-cancer targeting therapy

Graphene oxide (GO) has attracted huge attention in biomedical field in recent years. However, limited attempts have been invested in utilizing GO on active targeted delivery for gene therapy in liver cancer treatments. Glycyrrhetinic acid (GA) has been reported to be widely used as a targeting ligand to functionalize nanomaterials to treat hepatocellular carcinoma. In this article, GA is employed as a liver targeting ligand to construct GA, polyethylene glycol (PEG), polyamidoamine dendrimer (Dendrimer) and nano-graphene oxide (NGO) conjugate (GA-PEG-NGO-Dendrimer, GPND) for siRNA delivery for the first time. As we expected, GPND exhibited excellent stability, low toxicity, negligible hemolytic activity and remarkably high transfection efficiency in vitro. We also found effective VEGFa gene silencing in both mRNA and protein level in HepG2 cells. Notably, siRNA efficiently gathered in liver tumor tissues by the delivery of GPND, and eventually the growth of tumor tissues were inhibited with enhanced targeting capability and no obvious pathological changes. Moreover, histopathological results preliminarily support the high in vivo safety of GPND/anti-VEGFa siRNA nanocomplex. Collectively, GPND/siRNA nanocomplex, with high safety, targeting and transfection as well as prolonged half-life, is a promising nanomedicine and may provide a new direction for highly-specific targeted gene therapy.

Hydrogels and Their Applications in Targeted Drug Delivery

Conventional drug delivery approaches are plagued by issues pertaining to systemic toxicity and repeated dosing. Hydrogels offer convenient drug delivery vehicles to ensure these disadvantages are minimized and the therapeutic benefits from the drug are optimized. With exquisitely tunable physical properties that confer them great controlled drug release features and the merits they offer for labile drug protection from degradation, hydrogels emerge as very efficient drug delivery systems. The versatility and diversity of the hydrogels extend their applications beyond targeted drug delivery also to wound dressings, contact lenses and tissue engineering to name but a few. They are 90% water, and highly porous to accommodate drugs for delivery and facilitate controlled release. Herein we discuss hydrogels and how they could be manipulated for targeted drug delivery applications. Suitable examples from the literature are provided that support the recent advancements of hydrogels in targeted drug delivery in diverse disease areas and how they could be suitably modified in very different ways for achieving significant impact in targeted drug delivery. With their enormous amenability to modification, hydrogels serve as promising delivery vehicles of therapeutic molecules in several disease conditions, including cancer and diabetes.

Glycyrrhizic acid as a multifunctional drug carrier - From physicochemical properties to biomedical applications: A modern insight on the ancient drug

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Glycyrrhizic acid (GA), saponin of licorice shows wide range of biological activity.

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Mechanism of GA activity on the cell and molecular level is rarely discussed.

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GA activity could be caused by the cell membrane modification.

Glycyrrhizic acid is the main active component of Licorice root which has been known in traditional Chinese and Japanese medicine since ancient times. In these cultures glycyrrhizic acid (GA) is one of the most frequently used drugs. However, only in 21-st century a novel unusual property of the GA to enhance the activity of other drugs has been discovered. The review describes briefly the experimental evidences of wide spectrum of own biological activities of glycyrrhizic acid as well as discusses the possible mechanisms of the ability of GA to enhance the activity of other drugs. We have shown that due to its amphiphilic nature GA is able to form self-associates in aqueous and non-aqueous media, as well as water soluble complexes with a wide range of lipophilic drugs. The main purpose of our review is to focus reader's attention on physicochemical studies of the molecular mechanisms of GA activity as a drug delivery system (DDS). In our opinion, the most intriguing feature of glycyrrhizic acid which might be the key factor in its therapeutic activity is the ability of GA to incorporate into the lipid bilayer and to increase the membrane fluidity and permeability. The ability of biomolecules and their aggregates to change the properties of cell membranes is of great significance, from both fundamental and practical points of view.

Pathogenic Viruses Commonly Present in the Oral Cavity and Relevant Antiviral Compounds Derived from Natural Products

Many viruses, such as human herpesviruses, may be present in the human oral cavity, but most are usually asymptomatic. However, if individuals become immunocompromised by age, illness, or as a side effect of therapy, these dormant viruses can be activated and produce a variety of pathological changes in the oral mucosa. Unfortunately, available treatments for viral infectious diseases are limited, because (1) there are diseases for which no treatment is available; (2) drug-resistant strains of virus may appear; (3) incomplete eradication of virus may lead to recurrence. Rational design strategies are widely used to optimize the potency and selectivity of drug candidates, but discovery of leads for new antiviral agents, especially leads with novel structures, still relies mostly on large-scale screening programs, and many hits are found among natural products, such as extracts of marine sponges, sea algae, plants, and arthropods. Here, we review representative viruses found in the human oral cavity and their effects, together with relevant antiviral compounds derived from natural products. We also highlight some recent emerging pharmaceutical technologies with potential to deliver antivirals more effectively for disease prevention and therapy.

Orthogonal self-assembly of an organoplatinum(II) metallacycle and cucurbit[8]uril that delivers curcumin to cancer cells

Curcumin (Cur) is a naturally occurring anticancer drug isolated from the Curcuma longa plant. It is known to exhibit anticancer properties via inhibiting the STAT3 phosphorylation process. However, its poor water solubility and low bioavailability impede its clinical application. Herein, we used organoplatinum(II) ← pyridyl coordination-driven self-assembly and a cucurbit[8]uril (CB[8])-mediated heteroternary host-guest complex formation in concert to produce an effective delivery system that transports Cur into the cancer cells. Specifically, a hexagon 1, containing hydrophilic methyl viologen (MV) units and 3,4,5-Tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzoyl groups alternatively at the vertices, has been synthesized and characterized by several spectroscopic techniques. The MV units of 1 underwent noncovalent complexation with CB[8] to yield a host-guest complex 4. Cur can be encapsulated in 4, via a 1:1:1 heteroternary complex formation, resulting in a water-soluble host-guest complex 5. The host-guest complex 5 exhibited ca 100-fold improved IC₅₀ values relative to free Cur against human melanoma (C32), melanoma of rodents (B16F10), and hormone-responsive (MCF-7) and triple-negative (MDA-MB231) breast cancer cells. Moreover, strong synergisms of Cur with 1 and 4 with combinatorial indexes of <1 across all of the cell lines were observed. An induced apoptosis with fragmented DNA pattern and inhibited expression of phosphor-STAT3 supported the improved therapeutic potential of Cur in heteroternary complex 5.

Controlled release of 18-β-glycyrrhetic acid by nanodelivery systems increases cytotoxicity on oral carcinoma cell line

The topical treatment for oral mucosal diseases is often based on products optimized for dermatologic applications; consequently, a lower therapeutic effect may be present. 18-β-glycyrrhetic acid (GA) is extracted from Glycirrhiza glabra. The first aim of this study was to test the cytotoxicity of GA on PE/CA-PJ15 cells. The second aim was to propose and test two different delivery systems, i.e. nanoparticles and fibers, to guarantee a controlled release of GA in vitro. We used chitosan and poly(lactic-co-glycolic) acid based nanoparticles and polylactic acid fibers. We tested both delivery systems in vitro on PE/CA-PJ15 cells and on normal human gingival fibroblasts (HGFs). The morphology of GA-loaded nanoparticles (GA-NPs) and fibers (GA-FBs) was investigated by electron microscopy and dynamic light scattering; GA release kinetics was studied spectrophotometrically. MTT test was used to assess GA cytotoxicity on both cancer and normal cells. Cells were exposed to different concentrations of GA (20-500 μmol l^-1) administered as free GA (GA-f), and to GA-NPs or GA-FBs. ROS production was evaluated using dichlorodihydrofluorescein as a fluorescent probe. Regarding the cytotoxic effect of GA on PE/CA-PJ15 cells, the lowest TC₅₀ value was 200 μmol l^-1 when GA was added as GA-NPs. No cytotoxic effects were observed when GA was administered to HGFs. N-acetyl Cysteine reduced mortality induced by GA-f in PE/CA-PJ15 cells. The specific effect of GA on PE/CA-PJ15 cells is mainly due to the different sensitivity of cancer cells to ROS over-production; GA-NPs and GA-FBs formulations increase, in vitro, this toxic effect on oral cancer cells.

Synthesis of a Block Copolymer Exhibiting Cell-Responsive Phytochemical Release for Cancer Therapy

Phytochemicals constitute a promising class of therapeutics for the treatment of various diseases, but their delivery poses significant challenges. In this work, a nanoscale polyactive emulsion was designed for smart, cell-responsive delivery of a curcumin prodrug (curcumin dicarboxylate, CDA) that was chemically conjugated to enzymatically labile oligo-peptides with polycaprolactone (PCL) as the carrier. Matrix metalloproteinase (MMP)-sensitive (PLGLYAL) or nonsensitive (GPYYPLG) peptides were used as spacers for conjugating CDA and PCL. This CDA nanoemulsion incorporating the MMP-sensitive sequence exhibited markedly higher anti-cancer activity, cell internalization, and generation of reactive oxygen species in cancer cells in vitro than the control with the nonsensitive oligopeptide. Moreover, the nanopolyactives induced minimal cytotoxicity in noncancerous cell line. This work presents a unique strategy to engineer smart nano-polyactives for efficient and targeted delivery of phytochemicals.

Glycyrrhetinic acid as a hepatocyte targeting unit for an anticancer drug delivery system with enhanced cell type selectivity

Herein, we explore glycyrrhetinic acid (GA) as an active targeting ligand for hepatocellular carcinoma (HCC) using a small molecule approach.