Exploration of the Natural Active Small-Molecule Drug-Loading Process and Highly Efficient Synergistic Antitumor Efficacy

Natural gambogic acid-tuned self-assembly of nanodrugs towards synergistic chemophototherapy against breast cancer

Gambogic acid (GA) as a naturally derived chemotherapeutic agent is of increasing interest for antitumor therapy. However, current research mainly focuses on improving the pharmacological properties to overcome the shortcomings in clinical applications or as a synergistic anticancer agent in combination with chemotherapy and chemophototherapy. Yet, the material properties of GA (e.g., self-assembly) are often neglected. Herein, we validated the self-assembly function of GA and its huge potential as a single-component active carrier for synergistic delivery using pyropheophorbide-a (PPa) as a drug model. The results showed that self-assembled GA drives the formation of nano-GA/PPa mainly through noncovalent interactions such as π-π stacking, hydrophobic interactions, and hydrogen bonding. Additionally, although no significant differences in cytotoxicity were found between the individual in vitro chemotherapy and combined chemophototherapy, the as-prepared nano-GA/PPa exhibits remarkably improved water solubility and multiple favorable therapeutic features, leading to a prominent in vivo photochemotherapy efficiency of 89.3% inhibition rate with reduced hepatotoxicity of GA. This work highlights the potential of self-assembled GA as a drug delivery carrier for synergistic biomedical applications.

Advanced researches of traditional uses, phytochemistry, pharmacology, and toxicology of medical Uncariae Ramulus Cum Uncis

ETHNOPHARMACOLOGICAL RELEVANCE

Medical Uncariae Ramulus Cum Uncis consists of Uncaria rhynchophylla (Miq.) Miq. ex Havil, Uncaria macrophylla Wall, Uncaria sinensis (Oliv.) Havil, Uncaria hirsuta Havil, and Uncaria sessilifructus Roxb, which belongs to the species widely used in the genus Uncaria. These species resource widely distributed in China and abroad, and the hook-bearing stem is the primary constituent enrichment site. There are many different forms and architectures of chemicals, depending on the extraction site. Traditional remedies employing URCU had been used widely in antiquity and were first compiled in renowned ancient masterpiece 'Mingyi Bielu ()' written by Hongjing Tao. In modern pharmacological studies, both the total extracts and the phytoconstituents isolated from URCU have been shown to have neuroprotective, antioxidant, anti-inflammatory, anticancer, antibacterial, and autophagy-enhancer properties.

AIM OF THE STUDY

This review concentrates on the traditional uses, phytochemistry, pharmacology, toxicology, and nanomaterials studies of URCU, with a perspective to assist with further research and advance.

MATERIAL AND METHODS

The Chinese and English literature studies of this review are based on these database searches including Science Direct, CNKI, Wiley online library, Spring Link, Web of Science, PubMed, Medalink, Google scholar, Elsevier, ACS Publications, iPlant, Missouri Botanical Garden, Plant of the World Online. The pertinent data on URCU was gathered.

RESULTS

Based on the examination of the genus Uncaria, 107 newly marked chemical compositions have been identified from URCU from 2015 to present, including alkaloids, terpenoids, flavonoids, steroids, and others. Pharmacological studies have demonstrated that URCU has a variety of benefits in diseases such as neurodegenerative diseases, cancer, cardiovascular diseases, diabetes, and migraine, due to its neuroprotective, anti-inflammatory, antioxidant, anti-tumor, anti-bacterial and anti-viral properties. According to metabolic and toxicological studies, the dosage, frequency, and interactions of the drugs that occur in vivo are of great significance for determining whether the organic bodies can perform efficacy or produce toxicity. The research on URCU-mediated nanomaterials is expanding and increasing in order to address the inadequacies of conventional Chinese medicine. The alkaloids in URCU have the capability to self-assemble with other classes of components in addition to being biologically active.

CONCLUSION

URCU plants are widely distributed, abundant in chemical constituents, and widely used in both traditional and modern medicine for a variety of pharmacological effects. The utilization of herbal medicines can be raised by assessing the pharmacological distinctions among several species within the same genus and may accelerate the modernization of traditional Chinese medicine. Controlling the concentration of drug administration, monitoring metabolic markers, and inventing novel nanotechnologies are effective strategies for synergistic influence and detoxification to alleviate the main obstacles that toxicity, low bioavailability, and poor permeability. This review can assist further research and advances.

Self-Assembled Matrine-PROTAC Encapsulating Zinc(II) Phthalocyanine with GSH-Depletion-Enhanced ROS Generation for Cancer Therapy

The integration of a multidimensional treatment dominated by active ingredients of traditional Chinese medicine (TCM), including enhanced chemotherapy and synergistically amplification of oxidative damage, into a nanoplatform would be of great significance for furthering accurate and effective cancer treatment with the active ingredients of TCM. Herein, in this study, we designed and synthesized four matrine-proteolysis-targeting chimeras (PROTACs) (depending on different lengths of the chains named LST-1, LST-2, LST-3, and LST-4) based on PROTAC technology to overcome the limitations of matrine. LST-4, with better anti-tumor activity than matrine, still degrades p-Erk and p-Akt proteins. Moreover, LST-4 NPs formed via LST-4 self-assembly with stronger anti-tumor activity and glutathione (GSH) depletion ability could be enriched in lysosomes through their outstanding enhanced permeability and retention (EPR) effect. Then, we synthesized LST-4@ZnPc NPs with a low-pH-triggered drug release property that could release zinc(II) phthalocyanine (ZnPc) in tumor sites. LST-4@ZnPc NPs combine the application of chemotherapy and phototherapy, including both enhanced chemotherapy from LST-4 NPs and the synergistic amplification of oxidative damage, through increasing the reactive oxygen species (ROS) by photodynamic therapy (PDT), causing an GSH decrease via LST-4 mediation to effectively kill tumor cells. Therefore, multifunctional LST-4@ZnPc NPs are a promising method for killing cancer cells, which also provides a new paradigm for using natural products to kill tumors.

Nanoparticle encapsulation using self-assembly abietic acid to improve oral bioavailability of curcumin

This research constructed composite nanoparticles (NPs) using abietic acid (AA) as a carrier for significantly enhancing the bioavailability of curcumin (CCM). CCM-loaded AA NPs were synthesized using a low-energy microemulsification method, and the obtained nanoparticles had a spherical morphology with an average diameter of 458.66 nm, a narrow size distribution and a negative surface charge of -19.13 mV. The encapsulation efficiency of CCM was 17.98 %, while its solubility was 20-fold that of free curcumin. FITR, UV, and MD revealed hydrogen bonds and hydrophobic forces between AA and CCM. Thein-vitrorelease profile showed sustainable release of CCM in simulated gastric and intestinal fluids up to 2 h at 37 °C. In cellular studies, CCM-loaded AA NPs with the same CCM concentration exhibited greater bioaccessibility and bioavailability than free CCM. These data suggested a possible utilization of AA NPs in improving water solubility, bioavailability and activity of lipophilic bioactive food factors.

Nano-Drug Delivery Systems Based on Natural Products

Natural products have proven to have significant curative effects and are increasingly considered as potential candidates for clinical prevention, diagnosis, and treatment. Compared with synthetic drugs, natural products not only have diverse structures but also exhibit a range of biological activities against different disease states and molecular targets, making them attractive for development in the field of medicine. Despite advancements in the use of natural products for clinical purposes, there remain obstacles that hinder their full potential. These challenges include issues such as limited solubility and stability when administered orally, as well as short durations of effectiveness. To address these concerns, nano-drug delivery systems have emerged as a promising solution to overcome the barriers faced in the clinical application of natural products. These systems offer notable advantages, such as a large specific surface area, enhanced targeting capabilities, and the ability to achieve sustained and controlled release. Extensive in vitro and in vivo studies have provided further evidence supporting the efficacy and safety of nanoparticle-based systems in delivering natural products in preclinical disease models. This review describes the limitations of natural product applications and the current status of natural products combined with nanotechnology. The latest advances in nano-drug delivery systems for delivery of natural products are considered from three aspects: connecting targeting warheads, self-assembly, and co-delivery. Finally, the challenges faced in the clinical translation of nano-drugs are discussed.

Advanced application of nanotechnology in active constituents of Traditional Chinese Medicines

Traditional Chinese Medicines (TCMs) have been used for centuries for the treatment and management of various diseases. However, their effective delivery to targeted sites may be a major challenge due to their poor water solubility, low bioavailability, and potential toxicity. Nanocarriers, such as liposomes, polymeric nanoparticles, inorganic nanoparticles and organic/inorganic nanohybrids based on active constituents from TCMs have been extensively studied as a promising strategy to improve the delivery of active constituents from TCMs to achieve a higher therapeutic effect with fewer side effects compared to conventional formulations. This review summarizes the recent advances in nanocarrier-based delivery systems for various types of active constituents of TCMs, including terpenoids, polyphenols, alkaloids, flavonoids, and quinones, from different natural sources. This review covers the design and preparation of nanocarriers, their characterization, and in vitro/vivo evaluations. Additionally, this review highlights the challenges and opportunities in the field and suggests future directions for research. Nanocarrier-based delivery systems have shown great potential in improving the therapeutic efficacy of TCMs, and this review may serve as a comprehensive resource to researchers in this field.

Insights into the Mechanism of Supramolecular Self-Assembly in the Astragalus membranaceus-Angelica sinensis Codecoction

Astragalus membranaceus (Fisch.) Bge. (AM) and Angelica sinensis (Oliv.) Diels (AS) constitute a classic herb pair in prescriptions to treat myocardial fibrosis. To date, research on the AM-AS herb pair has mainly focused on the chemical compositions associated with therapeutic efficacy. However, supermolecules actually exist in herb codecoctions, and their self-assembly mechanism remains unclear. In this study, supermolecules originating from AM-AS codoping reactions (AA-NPs) were first reported. The chemical compositions of AA-NPs showed a dynamic self-assembly process. AA-NPs with different decoction times had similar surface groups and amorphous states; however, the size distributions of these nanoparticles might be different. Taking the interaction between Z-ligustilide and astragaloside IV as an example to understand the self-assembly mechanism of AA-NPs, it was found that the complex could be formed with a molar ratio of 2:1. Later, AA-NPs were proven to be effective in the treatment of myocardial fibrosis both in vivo and in vitro, the in-depth mechanisms of which were related to the recovery of cardiac function, reduced collagen deposition, and inhibition of the endothelial-to-mesenchymal transition that occurred in the process of myocardial fibrosis. Thus, AA-NPs may be the chemical material basis of the molecular mechanism of the AM-AS decoction in treating isoproterenol-induced myocardial fibrosis. Taken together, this work provides a supramolecular strategy for revealing the interaction between effective chemical components in herb-pair decoctions.

Nanoparticles prepared by polysaccharides extracted from Biyang floral mushroom loaded with resveratrol: Characterization, bioactivity and release behavior under in vitro digestion

Resveratrol (RES) is a common active factor in the functional food field, but poor water solubility and low bioavailability have limited its application. In the present study, the novel nanoparticles (RES-CBFMP NPs) using floral mushroom polysaccharide as the wall material have been developed for delivering RES, aiming to overcome its application shortcomings. After ratio optimization, RES-CBFMP NPs (RES-CBFMP,1:8 w/w), which combined through the hydrogen bonds between RES and CBFMP, showed the best overall performance, with the encapsulation efficiency (EE) of 49.74 ± 0.16%, loading efficiency (LE) of 5.53 ± 0.02%, particle size of 158.56 ± 1.97 nm and zeta-potential of -17.56 ± 0.24 mV. In addition, RES-CBFMP NPs exhibited good physicochemical stabilities, sustained gastrointestinal digestive release property, as well as improved in vitro antioxidant and anticancer activities. This study may contribute to the development of RES oral delivery systems and the application of hydrophobic active molecules in the functional food field.

Formation of a traditional Chinese medicine self-assembly nanostrategy and its application in cancer: a promising treatment

Traditional Chinese medicine (TCM) has been used for centuries to prevent and treat a variety of illnesses, and its popularity is increasing worldwide. However, the clinical applications of natural active components in TCM are hindered by the poor solubility and low bioavailability of these compounds. To address these issues, Chinese medicine self-assembly nanostrategy (CSAN) is being developed. Many active components of TCM possess self-assembly properties, allowing them to form nanoparticles (NPs) through various noncovalent forces. Self-assembled NPs (SANs) are also present in TCM decoctions, and they are closely linked to the therapeutic effects of these remedies. SAN is gaining popularity in the nano research field due to its simplicity, eco-friendliness, and enhanced biodegradability and biocompatibility compared to traditional nano preparation methods. The self-assembly of active ingredients from TCM that exhibit antitumour effects or are combined with other antitumour drugs has generated considerable interest in the field of cancer therapeutics. This paper provides a review of the principles and forms of CSAN, as well as an overview of recent reports on TCM that can be used for self-assembly. Additionally, the application of CSAN in various cancer diseases is summarized, and finally, a concluding summary and thoughts are proposed. We strongly believe that CSAN has the potential to offer fresh strategies and perspectives for the modernization of TCM.

Bionic natural small molecule co-assemblies towards targeted and synergistic Chemo/PDT/CDT

BACKGROUND

Multi-component nano-delivery systems based on chemotherapy (chemo)- photodynamic therapy (PDT)- chemodynamic therapy (CDT) have gained increased attention as a promising strategy to improve clinical outcomes in cancer treatment. However, there remains a challenge in developing biodegradable, biocompatible, less toxic, yet highly efficient multicomponent nanobased drug delivery systems (DDS). Here, our study presents the screening and development of a novel DDS based on co-assemblies natural small molecule (NSMs). These molecules (oleanolic acid, and betulinic acid) are combined with photosensitizers Chlorine6 (Ce6) and Cu²⁺ that are encapsulated by tumor cell membranes. This nanocarrier encapsulated in tumor cell membranes achieved good tumor targeting and a significant improvement in tumor accumulation.

METHODS

A reprecipitation method was used to prepare the co-assembled nanocarrier, followed by the introduction of Cu^2 + into the DDS (OABACe6 NPs). Then, by wrapping the surface of NPs with the cell membranes of 4T1 which is a kind of mouse breast cancer cells (CM@OABACe6/Cu NPs). and analysis of its structure and size distribution with UV-Vis, XPS, FT-IR, SEM, TEM, and DLS. The synergistic effects of in vitro chemotherapy, CDT and PDT and targeting were also validated by cellular and animal studies.

RESULTS

It was shown that CM@OABACe6/Cu NPs achieved good tumor targeting and a significant improvement in tumor accumulation. In the composite nano-assembly, the NSMs work together with the Ce6 to provide effective and safe chemo and PDT. Moreover, the effect of reduced PDT due to the depletion of reactive oxygen species (ROS) by excess glutathione (GSH) in the tumor can be counteracted when Cu^2 + is introduced. More importantly, it also confers CDT through a Fenton-like catalytic reaction with H₂O overexpressed at the tumor site.

CONCLUSIONS

By constructing CM@OABACe6/Cu NPs with homologous targeting, we create a triple synergistic platform for cancer therapy using PDT, chemo, and CDT. We propose here a novel combinatorial strategy for designing more naturally co-assembled small molecules, especially for the development of multifunctional synergistic therapies that utilize NSMs.

Recent advances in natural small molecules as drug delivery systems

Drug delivery systems (DDSs) are a multidisciplinary approach toward the effective delivery of drugs to their target sites. Natural small molecule (NSM) compounds with anticancer activity, self-assembly and co-assembly functions show great potential for application as novel DDSs in the biomedical field. NSMs are widely sourced, have many modification sites, and readily form hydrogen bonds, π-π interactions, van der Waals interactions, and other non-covalent bonds in solvents, resulting in ordered structures. Moreover, their good biocompatibility and bioactivity allow compositions based on these compounds to be used in life science applications such as tissue engineering, drug delivery and cell imaging, showing the potential medical value of NSMs as DDSs. In this review, we summarise the role, assembly principles and applications of natural products such as triterpenoids, diterpenoids, sterols, alkaloids and polysaccharides in the construction of small molecule systems, which are expected to provide an important reference for the development of more active natural nanomaterials and the study of single or multi-component interactions.

Photosensitive pro-drug nanoassemblies harboring a chemotherapeutic dormancy function potentiates cancer immunotherapy

Immunotherapy combined with effective therapeutics such as chemotherapy and photodynamic therapy have been shown to be a successful strategy to activate anti-tumor immune responses for improved anticancer treatment. However, developing multifunctional biodegradable, biocompatible, low-toxic but highly efficient, and clinically available transformed nano-immunostimulants remains a challenge and is in great demand. Herein, we report and design of a novel carrier-free photo-chemotherapeutic nano-prodrug COS-BA/Ce6 NPs by combining three multifunctional components-a self-assembled natural small molecule betulinic acid (BA), a water-soluble chitosan oligosaccharide (COS), and a low toxic photosensitizer chlorin e6 (Ce6)-to augment the antitumor efficacy of the immune adjuvant anti-PD-L1-mediated cancer immunotherapy. We show that the designed nanodrugs harbored a smart and distinctive "dormancy" characteristic in chemotherapeutic effect with desired lower cytotoxicity, and multiple favorable therapeutic features including improved ¹O₂ generation induced by the reduced energy gap of Ce6, pH-responsiveness, good biodegradability, and biocompatibility, ensuring a highly efficient, synergistic photochemotherapy. Moreover, when combined with anti-PD-L1 therapy, both nano-coassembly based chemotherapy and chemotherapy/photodynamic therapy (PDT) could effectively activate antitumor immunity when treating primary or distant tumors, opening up potentially attractive possibilities for clinical immunotherapy.

Supermolecules as a quality markers of herbal medicinal products

Herbal medicines have greatly contributed to human health worldwide for thousands of years. In particular, traditional Chinese medicine plays an essential role in the prevention and treatment of COVID-19. With the exponentially increasing use and global attention to herbal medicinal products (HMPs), efficacy and safety have become major public concerns in many countries. In general, the quantification and qualification of quality markers (Q-markers) is the most common way to solve this issue. In the last few decades, small molecules, including flavonoids, terpenes, phenylpropanoids, alkaloids, phenols, and glycosides have been extensively investigated as Q-markers for HMP quality control. With the development of biotechnology in the last decade, scientists have begun to explore HMPs macromolecules, including polysaccharides and DNA, for their establishment as Q-markers. In recent years, supermolecules with stronger biological activities have been found in HMPs. In this review, we summarize and discuss the current Q-markers for HMP quality control; in particular, the possibility of using supermolecules as Q-markers based on structure and activity was discussed.

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.

Carrier-free nanoplatforms from natural plants for enhanced bioactivity

BACKGROUND

Natural plants as well as traditional Chinese medicine have made outstanding contributions to the health and reproduction of human beings and remain the basis and major resource for drug innovation. Carrier-free nanoplatforms completely self-assembled by pure molecules or therapeutic components have attracted increasing attention due to their advantages of improved pharmacodynamics/pharmacokinetics, reduced toxicity, and high drug loading. In recent years, carrier-free nanoplatforms produced by self-assembly from natural plants have contributed to progress in a variety of therapeutic modalities. Notably, these nanoplatforms based on the interactions of components from different natural plants improve efficiency and depress toxicity.

AIM OF REVIEW

In this review, different types of self-assembled nanoplatforms are first summarized, mainly including nanoassemblies of pure small molecules isolated from different plants, extracellular vesicles separated from fresh plants, charcoal nanocomponents obtained from charred plants, and nanoaggregates from plants formulae decoctions. Key Scientific Concepts of Review: We mainly focus on composition, self-assembly mechanisms, biological activity and modes of action. Finally, a future perspective of existing challenges with respect to the clinical application of plant-based carrier-free nanoplatforms is discussed, which may be instructive to further develop effective carrier-free nanoplatforms from natural plants in the future.

Updated design strategies for oral delivery systems: maximized bioefficacy of dietary bioactive compounds achieved by inducing proper digestive fate and sensory attributes

Interest in the application of dietary bioactive compounds (DBC) in healthcare and pharmaceutical industries has motivated researchers to develop functional delivery systems (FDS) aiming to maximize their bioefficacy. As the direct and indirect health benefiting effects of DBC are acknowledged, traditional design principle of FDS aiming at improving the bioavailability of intact DBC is challenged by the updated one, where the maximized bioefficacy of DBC delivered by FDS will be achieved via rationally absorbed at target sites with proper metabolism pathways. This article briefly summarized the absorption and metabolic fates of orally digested DBC along with their direct and indirect mechanisms to perform health benefiting effects. Current strategies in designing the next generation FDS with an emphasis on their modulation effects on the distribution portion between the upper and lower digestive tract, portal vein and lymphatic absorption, human digestive and gut microbiota enzymatic mediated metabolism were highlighted. Updated research progresses of FDS in adjusting sensory attributes of food end products and inducing synergistic effects rooting from matrix materials and co-delivered cargos were also discussed. Challenges as well as future perspectives concerning the precise nutrition and the critical role of delivery systems in dietary intervention were proposed.

When Natural Compounds Meet Nanotechnology: Nature-Inspired Nanomedicines for Cancer Immunotherapy

Recent significant strides of natural compounds in immunomodulation have highlighted their great potential against cancer. Despite many attempts being made for cancer immunotherapy, the biomedical application of natural compounds encounters a bottleneck because of their unclear mechanisms, low solubility and bioavailability, and limited efficacy. Herein, we summarize the immune regulatory mechanisms of different natural compounds at each step of the cancer-immunity cycle and highlight their anti-tumor potential and current limitations. We then propose and present various drug delivery strategies based on nanotechnology, including traditional nanoparticles (NPs)-based delivery strategies (lipid-based NPs, micelles, and polysaccharide/peptide/protein-based NPs) and novel delivery strategies (cell-derived NPs and carrier-free NPs), thus providing solutions to break through existing bottlenecks. Furthermore, representative applications of nature-inspired nanomedicines are also emphasized in detail with the advantages and disadvantages discussed. Finally, the challenges and prospects of natural compounds for cancer immunotherapy are provided, hopefully, to facilitate their far-reaching development toward clinical translation.

Nanomaterials in Animal Husbandry: Research and Prospects

Anti-inflammatory, antiviral, and anti-cancer treatments are potential applications of nanomaterials in biology. To explore the latest discoveries in nanotechnology, we reviewed the published literature, focusing on co-assembled nanoparticles for anti-inflammatory and anti-tumor properties, and their applications in animal husbandry. The results show that nanoparticles have significant anti-inflammation and anti-tumor effects, demonstrating broad application prospects in animal breeding. Furthermore, pooled evidence suggests that the mechanism is to have a positive impact on inflammation and tumors through the specific drug loading by indirectly or directly targeting the disease sites. Because the precise regulatory mechanism remains unclear, most studies have focused on regulating particular sites or even specific genes in the nucleus by targeting functional co-assembled nanoparticles. Hence, despite the intriguing scenarios for nanotechnology in farmed animals, most results cannot yet be translated into field applications. Overall, nanomaterials outperformed similar materials in terms of anti-inflammatory and anti-tumor. Nanotechnology also has promising applications in animal husbandry and veterinary care, and its application and development in animal husbandry remain an exciting area of research.

Natural saponin and cholesterol assembled nanostructures as the promising delivery method for saponin

The application of saponins has been restricted by problems such as hemolysis, low bioavailability, and poor solubility. So it is imperative to find a strategy to deliver saponins safely and efficiently. Here, through bottom-up technique, we design and prepare two saponin-cholesterol (Cho) nano-complex: dioscin (Dio, steroid saponin)-Cho nanofibers (NFs) and escin Ia (EIa, triterpene saponin)-Cho nanoparticles (NPs). It is found that the hydrophobic force and hydrogen bonding drive the two pairs of molecules to bind in different directions (the 3β-OH of Cho face the sugar chain of EIa and the 22α-O of Dio, respectively) and finally show spherical NPs (EIa-Cho) and fibrous NFs (Dio-Cho). The equimolar saponin-Cho complex, Dio NFs and EIa NPs, reveal potent cytotoxicities against mouse breast cancer cells (4T1) in vitro. In vivo results confirm the antitumor (4T1 mice model) efficacy of PEGylation Dio NFs (10 mg/kg, i.v.) with a tumor inhibition rate of 61%, meanwhile, it does not cause extreme irritation and pain as free Dio does to mice. Moreover, compared with the free drug, the prepared nano-complex can significantly reduce hemolysis and organ toxicity. Our research reduces the toxicity of saponins while retaining their antitumor activity, providing a new strategy for the delivery of saponins.

Supramolecular assemblies based on natural small molecules: Union would be effective

Natural products have been used to prevent and treat human diseases for thousands of years, especially the extensive natural small molecules (NSMs) such as terpenoids, steroids and glycosides. A quantity of studies are confined to concern about their chemical structures and pharmacological activities at the monomolecular level, whereas the spontaneous assemblies of them in liquids yielding supramolecular structures have not been clearly understood deeply. Compared to the macromolecules or synthetic small molecular compounds, NSMs have the inherent advantages of lower toxicity, better biocompatibility, biodegradability and biological activity. Self-assembly of single component and multicomponent co-assembly are unique techniques for designing supramolecular entities. Assemblies are of special significance due to their range of applications in the areas of drug delivery systems, pollutants capture, materials synthesis, etc. The assembled mechanism of supramolecular NSMs which are mainly driven by multiple non-covalent interactions are summarized. Furthermore, a new hypothesis aimed to interpret the integration effects of multi-components of traditional Chinese medicines (TCMs) inspired on the theory of supramolecular assembly is proposed. Generally, this review can enlighten us to achieve the qualitative leap for understanding natural products from monomolecule to supramolecular structures and multi-component interactions, which is valuable for the intensive research and application.

Peritoneum-Inspired Janus Porous Hydrogel with Anti-Deformation, Anti-Adhesion, and Pro-Healing Characteristics for Abdominal Wall Defect Treatment

Implantable meshes used in tension-free repair operations facilitate treatment of internal soft-tissue defects. However, clinical meshes fail to achieve anti-deformation, anti-adhesion, and pro-healing properties simultaneously, leading to undesirable surgery outcomes. Herein, inspired by the peritoneum, a novel biocompatible Janus porous poly(vinyl alcohol) hydrogel (JPVA hydrogel) is developed to achieve efficient repair of internal soft-tissue defects by a facile yet efficient strategy based on top-down solvent exchange. The densely porous and smooth bottom-surface of JPVA hydrogel minimizes adhesion of fibroblasts and does not trigger any visceral adhesion, and its loose extracellular-matrix-like porous and rough top-surface can significantly improve fibroblast adhesion and tissue growth, leading to superior abdominal wall defect treatment to commercially available PP and PCO meshes. With unique anti-swelling property (maximum swelling ratio: 6.4%), JPVA hydrogel has long-lasting anti-deformation performance and maintains high mechanical strength after immersion in phosphate-buffered saline (PBS) for 14 days, enabling tolerance to the maximum abdominal pressure in an internal wet environment. By integrating visceral anti-adhesion and defect pro-healing with anti-deformation, the JPVA hydrogel patch shows great prospects for efficient internal soft-tissue defect repair.

pH-Responsive Hyaluronic Acid Nanoparticles for Enhanced Triple Negative Breast Cancer Therapy

Purpose

Methods

Results

Conclusion

Research progress on self-assembled nanodrug delivery systems

In recent years, nanodrug delivery systems have attracted increasing attention due to their advantages, such as the high drug loading, low toxicity and side effects, improved bioavailability, long half-life, well...

Ursolic acid inhibits proliferation, migration and invasion of human papillary thyroid carcinoma cells via CXCL12/CXCR4/CXCR7 axis through cancer-associated fibroblasts

As a pentacyclic triterpenoid compound, Ursolic acid (UA) broads range of biological effects. CXCL12 is a ligand for CXCR4 and CXCR7 proteins on thyroid cancer cells. Here we examined the effects of UA on the proliferation, migration and invasion of papillary thyroid carcinoma (PTCs) in a dose-manner. In addition, UA can reduce the expression levels of CXCR4 and CXCR7 in PTCs. In addition to this direct anticancer pathway, studies have shown that UA can play an anticancer role by affecting the secretion of CXCL12 in cancer-associated fibroblasts (CAFs). After treated with UA, normal fibroblasts and CAFs culture medium (CM) showed differential CXCL12 expression levels. We prepared fibroblast conditioned medium according to the intervention of UA, then cultured TPC-1 and B-CPAP cells with differential CM, and detected significant differences in the proliferation, migration and invasion of cancer cells. Our findings uncovered an indirect anticancer mechanism of UA. This cancer chemopreventive properties is expected to make UA a clinically useful chemopreventive agent.

Research Progress of Carrier-Free Antitumor Nanoparticles Based on Phytochemicals

Cancer is a major worldwide public health issue, responsible for millions of deaths every year. Cancer cases and deaths are expected to increase rapidly with population growth, age, and lifestyle behaviors that increase cancer risk. Long-term chemotherapy results in acquired drug resistance. Traditional treatment methods have limitations and cannot effectively treat distal metastatic cancers. Application of nanocarriers in multi-chemotherapy must be promoted. With research progress, the shortcomings of traditional nanocarriers have gradually become evident. Carrier-free nanodrugs with desirable bioactivity have attracted considerable attention. In this review, we provide an overview of recent reports on several carrier-free nanodrug delivery systems based on phytochemicals. This review focuses on the advantages of carrier-free nanodrugs, and provides new insights for establishment of ideal cancer treatment nanosystems.

Corosolic acid and its structural analogs: A systematic review of their biological activities and underlying mechanism of action

BACKGROUND

The corosolic acid (CA), also known as plant insulin, is a pentacyclic triterpenoid extracted from plants such as Lagerstroemia speciosa. It has been shown to have anti-diabetic, anti-inflammatory and anti-tumor effects. Its structural analogs ursolic acid (UA), oleanolic acid (OA), maslinic acid (MA), asiatic acid (AA) and betulinic acid (BA) display similar individual pharmacological activities to those of CA. However, there is no systematic review documenting pharmacological activities of CA and its structural analogues. This study aims to fill this gap in literature.

PURPOSE

This systematic review aims to summarize the medical applications of CA and its analogues.

METHODS

A systematic review summarizes and compares the extraction techniques, pharmacokinetic parameters, and pharmacological effects of CA and its structural analogs. Hypoglycemic effect is one of the key inclusion criteria for searching Web of Science, PubMed, Embase and Cochrane databases up to October 2020 without language restrictions. 'corosolic acid', 'ursolic acid', 'oleanolic acid', 'maslinic acid', 'asiatic acid', 'betulinic acid', 'extraction', 'pharmacokinetic', 'pharmacological' were used to extract relevant literature. The PRISMA guidelines were followed.

RESULTS

At the end of the searching process, 140 articles were selected for the systematic review. Information of CA and five of its structural analogs including UA, OA, MA, AA and BA were included in this review. CA and its structural analogs are pentacyclic triterpenes extracted from plants and they have low solubilities in water due to their rigid scaffold and hydrophobic properties. The introduction of water-soluble groups such as sugar or amino groups could increase the solubility of CA and its structural analogs. Their biological activities and underlying mechanism of action are reviewed and compared.

CONCLUSION

CA and its structural analogs UA, OA, MA, AA and BA are demonstrated to show activities in lowering blood sugar, anti-inflammation and anti-tumor. Their oral absorption and bioavailability can be improved through structural modification and formulation design. CA and its structural analogs are promising natural product-based lead compounds for further development and mechanistic studies.

Phytonanomaterials as therapeutic agents and drug delivery carriers

Medicinal plants have been a major resource for drug discovery. Emerging evidence shows that in addition to pharmacologically active components, medicinal plants also contain phytochemical nanomaterials, or phytonanomaterials, which form nanoparticles for drug delivery. In this review, we examine the evidence supporting the existence of phytonanomaterials. Next, we review identification, isolation, and classification of phytonanomaterials, characteristics of phytonanomaterial-derived nanoparticles, and molecular mechanisms of phytonanomaterial assembly. We will then summarize the current progress in exploring phytonanomaterial-derived NPs as therapeutic agents and drug delivery carriers for disease treatment. Last, we will provide perspectives on future discovery and applications of phytonanomaterials.

Nanoformulations of Ursolic Acid: A Modern Natural Anticancer Molecule

Background: Ursolic acid (UA) is a natural pentacyclic triterpene derived from fruit, herb, and other plants. UA can act on molecular targets of various signaling pathways, inhibit the growth of cancer cells, promote cycle stagnation, and induce apoptosis, thereby exerting anticancer activity. However, its poor water-solubility, low intestinal mucosal absorption, and low bioavailability restrict its clinical application. In order to overcome these deficiencies, nanotechnology, has been applied to the pharmacological study of UA.

Objective: In this review, we focused on the absorption, distribution, and elimination pharmacokinetics of UA in vivo, as well as on the research progress in various UA nanoformulations, in the hope of providing reference information for the research on the anticancer activity of UA.

Methods: Relevant research articles on Pubmed and Web of Science in recent years were searched selectively by using the keywords and subheadings, and were summarized systematically.

Key finding: The improvement of the antitumor ability of the UA nanoformulations is mainly due to the improvement of the bioavailability and the enhancement of the targeting ability of the UA molecules. UA nanoformulations can even be combined with computational imaging technology for monitoring or diagnosis.

Conclusion: Currently, a variety of UA nanoformulations, such as micelles, liposomes, and nanoparticles, which can increase the solubility and bioactivity of UA, while promoting the accumulation of UA in tumor tissues, have been prepared. Although the research of UA in the nanofield has made great progress, there is still a long way to go before the clinical application of UA nanoformulations.

Preparation and Characterization of Oleanolic Acid-Based Low-Molecular-Weight Supramolecular Hydrogels Induced by Heating

The natural-product-based low-molecular-weight supramolecular hydrogels (LMWSHs) induced by heating are rarely reported. In this work, a simple salt of oleanolic acid (OA) and choline ([choline][OA]) was used as the natural product hydrogelator (NPHG) to form LMWSHs. Unlike common sol-gel transitions, the OA-based LMWSH displayed a unique property with which the system could undergo a phase transition from the sol state to the gel state upon heating. Moreover, the phase separation was observed in sol and gel states when the temperature was elevated with nonreversible transparent-turbid transitions. LMWSHs showed good stability and injectability and the potential to be a drug delivery vehicle for sustained release of drugs. In this regard, this work provided a facile approach to designing an OA-based NPHG for preparing heat-induced LMWSHs.

Nano-assembly of ursolic acid with platinum prodrug overcomes multiple deactivation pathways in platinum-resistant ovarian cancer

As the most common cause of gynecological cancer-related deaths worldwide, ovarian cancer requires novel therapy strategies. Pt(ii)-Based antitumor drugs (e.g. cisplatin) are one of the most successful and frequently used drugs in ovarian cancer chemotherapy at present. However, drug resistance and severe side effects are the major problems in cancer treatment. Herein, the design of a reduction responsive platinum(iv) (Pt(iv))/ursolic acid (UA)/polyethylene glycol (PEG) dual prodrug amphiphile (Pt(iv)-UA-PEG) to treat cisplatin-resistant ovarian cancer is reported for the first time. Pt(iv)-UA-PEG could self-assemble into nanoparticles (Pt(iv)-UA NPs) with a fixed and precise Pt/UA ratio, and a constantly high content of drugs. Pt(iv)-UA NPs could be efficiently taken up by cisplatin-resistant ovarian cancer cells and release the drug in intracellular reductive and acidic environments. In vitro studies show that the released UA and cisplatin have different anticancer mechanisms, and their synergistic effects overcome the detoxification and anti-apoptotic mechanisms of cancer cells. Furthermore, the in vivo results indicate that Pt(iv)-UA NPs have a prolonged blood circulation time, enhanced tumor accumulation, and significantly improved antitumor efficacy in A2780/DDP tumor-bearing mice, without causing any side effects. In summary, our results demonstrate that the development of the stimuli-responsive dual prodrug amphiphile nano-assembly provides a new strategy to overcome drug resistance.

Exploring the self-assembly mechanism and effective synergistic antitumor chemophototherapy of a biodegradable and glutathione responsive ursolic acid prodrug mediated photosensitive nanodrug

Supermolecularly assembled photochemotherapeutic nanocomposites composed of pure drug small molecules are promising for synergistically improved tumor therapy, yet potential multiple challenges remain to be addressed. Herein, we rationally designed a novel multifunctional small molecule disulfide modified natural pentacyclic triterpene of ursolic acid (UASS) that simultaneously possesses self-assembly ability, glutathione (GSH) responsivity, anticancer activity, biocompatibility and biodegradability and further constructed carrier-free GSH-sensitive photosensitive nanocomposite UASS-Ce6 NPs for safe and synergistically improved chemophototherapy. Specifically, UASS-Ce6 NPs exhibit improved 1O2 generation by reducing the energy gap (ΔEST) of Ce6 as determined by density functional theory. Meanwhile, molecular dynamics simulation revealed the possible reasons why free UASS self-assembles and UASS-Ce6 NPs with different assembled morphologies may be primarily attributed to the coplanar arrangement of UASS dimer units. Importantly, via noncovalent π-stacking and hydrophobic interactions, the resulting co-assemblies showed improved water solubility, increased intercellular ROS generation, desirable GSH sensibility, excellent biocompatibility, and enhanced tumor accumulation accompanied by rapid biodegradation, thus leading to significant in vitro and in vivo synergistic antitumor efficacy with favorable biosafety. This study provides a promising insight into the development of a self-assembled active single component platform with desirable stimuli responsiveness and biosafety toward synergistic antitumor therapy based on terpenoid natural small molecules.

Quantitative self-assembly of pure drug cocktails as injectable nanomedicines for synergistic drug delivery and cancer therapy

New strategies to fabricate nanomedicines with high translational capacity are urgently desired. Herein, a new class of self-assembled drug cocktails that addresses the multiple challenges of manufacturing clinically useful cancer nanomedicines was reported.

Methods: With the aid of a molecular targeted agent, dasatinib (DAS), cytotoxic cabazitaxel (CTX) forms nanoassemblies (CD NAs) through one-pot process, with nearly quantitative entrapment efficiency and ultrahigh drug loading of up to 100%.

Results: Surprisingly, self-assembled CD NAs show aggregation-induced emission, enabling particle trafficking and drug release in living cells. In preclinical models of human cancer, including a patient-derived melanoma xenograft, CD NAs demonstrated striking therapeutic synergy to produce a durable recession in tumor growth. Impressively, CD NAs alleviated the toxicity of the parent CTX agent and showed negligible immunotoxicity in animals.

Conclusions: Overall, this approach does not require any carrier matrices, offering a scalable and cost-effective methodology to create a new generation of nanomedicines for the safe and efficient delivery of drug combinations.

Self-assembled natural small molecule diterpene acids with favorable anticancer activity and biosafety for synergistically enhanced antitumor chemotherapy

Natural biocompatible materials such as self-assembled natural small molecule products (NSMP) with anticancer activity are of increasing interest for synergistic biomedical applications. Herein, we discovered and developed four new self-assembled tricyclic diterpene acids NSMP with favorable anticancer activity for synergistic and safe antitumor chemotherapy, including dehydroabietic acid, 15-hydroxy-dehydroabietic acid, abietic acid, and 12-hydroxyabietic acid. The self-assembled performance and mechanism of these four compounds with different morphologies were explored in detail by molecular dynamics simulation, and revealed the coplanarity and orderliness of molecular arrangements which are speculated to be responsible for the self-assembly into spheres or rods. The screened and optimized abietic acid (AA) was chosen to prepare the synergistic antitumor drug AA-PTX NPs by co-administration with paclitaxel through multiple hydrogen bonds. The resulting nanodrugs were internalized into cells through a lysosome acidification uptake pathway. The improved water-solubility, significantly enhanced in vitro cytotoxicity, and excellent biosafety, lead to a highly efficient and safe in vivo anticancer efficacy of 81.2% inhibition rate with only three doses. This work provides new insights to explore the self-assembly behavior of small molecules and broadens the types of self-assembled active NSMP, providing a promising perspective for the fabrication of active NSMP mediated medical agents for multiple synergistic therapies.

A Carrier-Free Folate Receptor-Targeted Ursolic Acid/Methotrexate Nanodelivery System for Synergetic Anticancer Therapy

PURPOSE

To avoid undefined metabolic mechanisms and to eliminate potential side effects of traditional nanocarriers, new green carriers are urgently needed in cancer treatment. Carrier-free nanoparticles (NPs) based on ursolic acid (UA) have attracted significant attention, but the UA NPs targeting the folate receptor have never been explored. We designed a novel self-assembled UA-Methotrexate (MTX) NPs targeting the folate-receptor and its synergetic anticancer activity was studied in vitro and in vivo.

METHODS

UA-MTX NPs were prepared using the solvent precipitation method. Characterization of the UA-MTX NPs preparation was performed using a size analyzer, transmission electron microscopy, and UV-vis spectrophotometry. The in vitro pH-responsive drug release capability of UA-MTX NPs was tested at different pH values. The UA-MTX NPs targeting of folates was determined by comparing the endocytosis rates of cell lines with low or overexpression of the folate receptor (A549 and MCF-7 cells). The cytotoxicity and cell apoptosis of UA-MTX NPs were also studied to determine the in vitro synergistic effects. Combination chemotherapy of UA-MTX NPs in vivo was evaluated using MCF-7 xenografted tumor models.

RESULTS

Compared with free UA or MTX, the water solubility of UA-MTX NPs improved significantly. Drug-release from the UA-MTX NPs was faster at pH 5.0 than pH 7.4, suggesting MTX-UA NPs could rapidly release MTX in the acidic conditions of the tumor microenvironment. Confocal laser scanning microscopy revealed the excellent folate receptor targeting of UA-MTX NPs in MCF-7 cells. Cytotoxicity and cell apoptosis results demonstrated greater antiproliferative capacity of UA-MTX NPs than that of free drug in folate receptor overexpressing MCF-7 cells. Anticancer effects in vivo suggested MTX-UA NPs exhibited good biological safety and could enhance antitumor efficacy due to the combination therapy.

CONCLUSION

Our findings indicate that the UA-MTX NPs targeting folate-receptors is an efficient strategy for combination chemotherapy.

New PTX-HS15/T80 Mixed Micelles: Cytotoxicity, Pharmacokinetics and Tissue Distribution

Compared with single micelle, the new PTX-HS15/T80 mixed micelle system (PTX-HS15/T80 MMs) had achieved better results in solubilization, stability, and sensitization before. Therefore, we intend to further verify the potential advantages of the mixed micelle delivery system through in vitro cytotoxicity test and animal test to understand the anticancer effect and in vivo pharmaceutical behavior of the system. In vitro cytotoxicity test showed that the new PTX-HS15/T80 MMs had a stronger ability to inhibit the proliferation of cancer cells. The results of in vivo pharmacokinetics showed that the micelle had shorter half-life, higher clearance rate, and lower blood concentration and had good blood clearance characteristics. The results of in vivo tissue distribution showed that, compared with the single micelle Taxol^®, the new PTX-HS15/T80 MMs had good distribution characteristics in the lung (AUC _{(lung 0-4 H)} increased about 26%) and low concentration in the heart (AUC _{(Heart 0-4 H)} decreased about 10%). Paclitaxel was mainly metabolized through the liver and kidney. The above results suggested that the new PTX-HS15/T80 MMs may have a certain therapeutic potential against lung cancer and reduce the toxic and side effects. In general, the mixed micelle delivery system was not only simple and cheap to prepare but also had certain advantages in vitro and in vivo, indicating that the combination of surfactants provides a good choice for solving the problem of insoluble drug delivery.

Carrier-Free Triterpene Prodrugs with Glutathione Response and Biosafety for Synergistically Enhanced Photochemotherapy

Carrier-free pure drug self-assembled nanosystems have been proposed as a promising strategy for synergetic anticancer therapy. Herein, we purposefully designed and synthesized disulfide-modified glutathione (GSH)-responsive natural pentacyclic triterpene betulinic acid (BA) with better biodegradability and biocompatibility to construct carrier-free photosensitive prodrugs BA-S-S/Ce6 NPs for synergistically enhanced and biosafe photochemotherapy. The molecular dynamics simulation elucidates the possible coassembly mechanism that the coplanar arrangement of BA-S-S dimeric may be primarily responsible for the formation of a long lamella-like or spherical morphology. The density functional theory calculations demonstrate that the reduced energy gap (ΔEST) of Ce6 facilitates the improved singlet oxygen generation of BA-S-S/Ce6 nanoparticles (NPs). The assembled prodrugs exhibited remarkable GSH-responsive property and multiple favorable therapeutic features, leading to enhanced synergistic antitumor efficacy without noticeable toxicity. Additionally, evaluation of the antitumor efficacy of another tetracyclic triterpene stigmasterol (ST)-mediated ST-S-S/Ce6 NPs further confirmed the effectiveness of this rational design. This work provides a promising insight for exploring the pure drug self-assembly behavior and construction of GSH-responsive carrier-free triterpenoid prodrugs toward improved multiple combination antitumor therapies.

A directed co-assembly of herbal small molecules into carrier-free nanodrugs for enhanced synergistic antitumor efficacy

Carrier-free nanomedicines without structural modification are attractive for the development of natural small molecules (NSMs) and biomedical applications. Moreover, the combination of NSMs is expected to obtain nanomedicines with high efficacy and low side effects due to their inherent pharmacological activities and health benefits. However, poor water solubility and low bioavailability of NSMs limit their wider biomedical and clinical applications. In this study, we revealed the co-assembly properties of pentacyclic triterpenoids and constructed a series of carrier-free nanodrugs, which are co-assembled nanoparticles (NPs) formed by the combination of two NSMs via a supramolecular assembly strategy. Experimental work and simulation studies were combined to reveal the co-assembly mechanism of non-covalent interactions between NSMs. Not only do co-assembled NPs have rapid cellular uptake ability and passive targeting tumor ability based on the EPR effect, but also their constituent units could arrest the cell cycle at different stages of tumor cells and induce apoptosis, showing synergistic anti-tumor effects (CI < 0.7). Compared with self-assembled NPs and positive control, co-assembled NPs show the strongest therapeutic effect in vivo. Importantly, the co-assembled NPs highlight the unique advantages of NSMs in terms of biosafety and health benefits, and systemic toxicity and histological examination confirm that co-assembled NPs have reliable biosafety, and no side effects and nano toxicity risks were observed.

Multi-Interactions in Ionic Liquids for Natural Product Extraction

Natural products with a variety of pharmacological effects are important sources for commercial drugs, and it is very crucial to develop effective techniques to selectively extract and isolate bioactive natural components from the plants against the background of sustainable development. Ionic liquids (ILs) are a kind of designable material with unique physicochemical properties, including good thermal stability, negligible vapor pressure, good solvation ability, etc. ILs have already been used in pharmaceuticals for extraction, purification, drug delivery, etc. It has been reported that multi-interactions, like hydrogen bonding, hydrophobic interactions, play important roles in the extraction of bioactive components from the plants. In this review, recent progress in the understanding of scientific essence of hydrogen bonding, the special interaction, in ILs was summarized. The extraction of various natural products, one important area in pharmaceutical, by conventional and functional ILs as well as the specific roles of multi-interactions in this process were also reviewed. Moreover, problems existing in bioactive compound extraction by ILs and the future developing trends of this area are given, which might be helpful for scientists, especially beginners, in this field.

Carrier-free nanodrugs for safe and effective cancer treatment

Clinical applications of many anti-cancer drugs are restricted due to their hydrophobic nature, requiring use of harmful organic solvents for administration, and poor selectivity and pharmacokinetics resulting in off-target toxicity and inefficient therapies. A wide variety of carrier-based nanoparticles have been developed to tackle these issues, but such strategies often fail to encapsulate drug efficiently and require significant amounts of inorganic and/or organic nanocarriers which may cause toxicity problems in the long term. Preparation of nano-formulations for the delivery of water insoluble drugs without using carriers is thus desired, requiring elegantly designed strategies for products with high quality, stability and performance. These strategies include simple self-assembly or involving chemical modifications via coupling drugs together or conjugating them with various functional molecules such as lipids, carbohydrates and photosensitizers. During nanodrugs synthesis, insertion of redox-responsive linkers and tumor targeting ligands endows them with additional characteristics like on-target delivery, and conjugation with immunotherapeutic reagents enhances immune response alongside therapeutic efficacy. This review aims to summarize the methods of making carrier-free nanodrugs from hydrophobic drug molecules, evaluating their performance, and discussing the advantages, challenges, and future development of these strategies.

Bioactive Natural Small Molecule-Tuned Coassembly of Photosensitive Drugs for Highly Efficient Synergistic and Enhanced Type I Photochemotherapy

Self-assembling natural small molecules (NSMs) with favorable anticancer activity are of increasing interest as novel drug delivery platforms without structural modification for biomedical applications. However, a lack of knowledge and practicability of NSMs as drug carriers limited their current biomedical application. Here, via a green and facile supramolecular coassembly strategy, we report and develop a series of carrier-free terpenoid natural small molecule-mediated coassembled photosensitive drugs for enhanced and synergistic chemo/photodynamic therapy. After screening 17 terpenoid NSMs, we identified 11 compounds that could form coassembled NSMs-Ce6 NPs with regulatable drug sizes. Analysis of the representative betulonic acid (BC)-mediated nano-coassemblies (BC-Ce6 NPs) reveals the high efficiency of the coassembly strategy and highlights the tremendous potential of NSMs as novel drug delivery platforms. Through molecular dynamics simulation and theoretical calculations, we elucidate the mystery of the coassembly process, indicating that the linear coplanar arrangement of BC dimeric units is primarily responsible for the formation of rod-like or spherical morphology. Meanwhile, we demonstrated that the reduced energy gap between the singlet and triplet excited states (ΔE_ST) facilitates efficient reactive oxygen species generation by promoting ·OH generation via a type I photoreaction mechanism. The assembled nanodrugs exhibit multiple favorable therapeutic features, ensuring a remarkably enhanced, synergistic, and secure combinatorial anticancer efficacy of 93.6% with highly efficient tumor ablation. This work not only expands the possibility of natural biodegradable materials for wide biological applications but also provides a new perspective for the construction of NSM-mediated nano-coassemblies for precision therapy.

Paclitaxel and betulonic acid synergistically enhance antitumor efficacy by forming co-assembled nanoparticles

The side effects and low bioavailability of paclitaxel (PTX) limit its clinical application. The formation of self-assembled nanomedicines without structural modification is attractive for biomedical applications. Here, we constructed a supramolecular co-assembled nanoparticles (NPs), which is formed by betulonic acid (BTA) and PTX mainly through hydrogen bond interaction and hydrophobic interaction. It not only has the characteristics of NPs but also the activity of natural small molecules (NSMs). The results of in vitro and in vivo experiments showed that BTA-PTX NPs showed excellent synergistic enhancement of anti-tumor efficacy, because BTA and PTX have different anti-tumor mechanisms. What's more, BTA-PTX NPs showed excellent biosafety and low toxicity, because BTA has impressive biological activity and biosafety. This work provides an effective and simple method to construct high efficiency and minimize side effects of NPs, which provides more possibilities for the application of NSMs in drug delivery.

Nanomedicine-Cum-Carrier by Co-Assembly of Natural Small Products for Synergistic Enhanced Antitumor with Tissues Protective Actions

The application of natural small products with self-assembly characteristics in a drug-delivery system is attractive for biomedical applications because of its inherent biological safety and pharmacological activity, and there is no complex structural modification process. However, drug carriers with pharmacological effects have not been developed enough. Here, we report a pure natural nanomedicine-cum-carrier (NMC) drug delivery system. The NMC is formed by the direct co-assembly of two small molecular natural compounds through noncovalent interaction, and a molecular dynamics model for predicting the co-assembly of two small molecular compounds was established. The representative co-assembled NMC (oleanolic acid and glycyrrhetinic acid) not only shows excellent stability, high drug loading, and sustained release characteristics but also the co-assembled NMC formed by two small molecular compounds has a synergistic antitumor effect (CI < 0.7). After drug loading, the antitumor effect is further improved. In addition, this NMC highlights the unique advantages of active natural products in biosafety and health benefits. Compared with free drugs, it can reduce the liver damage caused by chemotherapy drugs through upregulating key antioxidant pathways. Compared to nonpharmacologically active drug delivery systems, it can reduce the risk of nanotoxicity. Taken together, this co-assembly drug-carrier system overcomes the shortcomings that pharmacologically active compounds cannot be directly applied, enhances the pharmacological activity of bioactive drug carriers, improves the antitumor efficacy, and slows down the side effects induced by chemotherapy drugs and the additional toxicity caused by long-term use of non-bioactive nanocarriers.

A highly atom-economical bioactive nanocarrier for synergistically enhanced antitumor with reduced liver injury

The drug-cum-carrier-type delivery system makes up for conventional nanocarriers that have no therapeutic efficacy and health benefits.