Challenges in the study of self-assembled aggregates in decoction of traditional Chinese medicine: A preliminary review / 药学学报

Decoction is the most commonly used dosage form in the clinical treatment of traditional Chinese medicine (TCM). During boiling, the violent movement of various active ingredients in TCM creates molecular forces such as hydrogen bonding, π-π stacking, hydrophobic interactions and electrostatic interactions, which results in the formation of self-assembled aggregates in decoction (SADs), including particles, gels, fibers, etc. It was found that SADs widely existed in decoction with biological activities superior to both effective monomers and their physical mixtures, providing a new idea to reveal the pharmacodynamic material basis of Chinese herbal medicine from the perspective of component interactions-phase structure. Recently, SADs have become a novel focus of research in TCM. This paper reviewed their relevant studies in recent years and found some issues to be concerned in the research, such as the polydispersity of decoction system, instability of active ingredient interactions during boiling, uncertainty of the aggregates self-assembly rules, and stability, purity, yield of the products. In this regard, some solutions and new ideas were presented for the integrated development and clinical application of SADs.

Effects of ferrocene position isomerization on the self-assembly behavior and antibacterial effect of coupled cationic peptides / 中国药房

OBJECTIVE To design the two isomers of ferrocene （Fc）-coupled cationic peptides （hereinafter referred to as “peptides”） [Fc-K（C8）FFHK and C8-K（Fc） FFHK] and the control peptide [C8-K（C8）FFHK]， and to explore the effects of Fc position isomerization on the self-assembly behavior and antibacterial effect of peptides. METHODS All isomerized peptides were prepared by standard solid-phase synthesis and purified by reversed-phase high-performance liquid chromatography. The stability of the peptide was analyzed by using UV spectrophotometry to detect UV absorption spectra， and Zeta potential analyzer to determine Zeta potential. The secondary structure was characterized by circular dichroism spectrum （CD）， Fourier transform infrared spectrometer （FTIR）， thioflavin T （ThT） fluorescence spectrum and transmission electron microscopy （TEM）. The differences in antibacterial activity and biocompatibility of the 2 kinds of isomerized peptides were evaluated by in vitro reactive oxygen species （ROS） generation test， growth curve determination test， plate method， cytotoxicity assay and hemolysis test. RESULTS Three peptides with purity higher than 95% were synthesized. The stability test results showed that the UV absorption spectra of Fc-K（C8）FFHK and C8-K（Fc）FFHK remained almost unchanged when placed at room temperature for 24 and 96 hours， and their Zeta potential were decreased by 0.3 mV and 0.5 mV， respectively. Secondary structure characterization results showed that Fc-K（C8）FFHK and C8-K（Fc）FFHK were self-assembled to form twisted nanoribbons and short nanofibers， respectively； C8-K（C8）FFHK was assembled into cylindrical nanofibers. The optical spectrum results showed that there were certain differences in the content of structures such as β-sheet and α-helix. The in vitro ROS generation test results showed that ROS generation efficiency of Fc-K（C8）FFHK at pH 6.0 was higher than C8-K（Fc）FFHK. The results of in vitro antibacterial activity showed that for methicillin-resistant Staphylococcus aureus， both the isomeric peptides had similar minimum inhibitory concentration （MIC） values of 50 μg/mL which were far lower than the control peptide （400 μg/mL）. To Escherichia coli， Fc-K（C8）FFHK had better antibacterial activity than C8-K（Fc）FFHK. Finally， cytotoxicity assay and hemolysis test results showed that both isomeric peptides had good biocompatibility. CONCLUSIONS By wangjingwen8021@163.com coupling Fc， the antibacterial activity of cationic self-assembled peptides can be improved. Regulating the position of Fc in the peptide sequence could regulate the self-assembly behavior and antibacterial effect of the self-assembled peptides.

Research progress of enzyme-instructed self-assembly molecules for tumor therapy and imaging / 中国药科大学学报

@#Self-assembly is the basis of the formation of biological macromolecular structure. Enzyme-instructed self-assembly (EISA) with the help of tool enzymes, realizing the conversion of small molecular compounds to supramolecular nanostructures at specific sites, become a new strategy for drug discovery.In recent years, the exploration of EISA for developing malignant cancer therapy and imaging has made considerable progress, achieving the precise regulation and tumor targeting of nanostructures. This paper reviews the latest progress of EISA in the field of tumor diagnosis and treatment, the functions and characteristics of tool enzymes such as alkaline phosphatase, sirtuin, tyrosinase, γ-glutamyltranspeptidase and caspase-3,summarizes the research status of EISA targeting multiple organelles in tumor therapy, and introduces the application of EISA in tumor imaging, aiming to provide reference forthe research of EISA strategy in tumor diagnosis and treatment.

Research progress of microparticles in traditional Chinese medicine decoction / 药学学报

Decoction is a classical dosage form of traditional Chinese medicines. In the process of decocting, various complex components produce physical interactions and chemical reactions, among which physical interactions include van der Waals force, hydrogen bond, electrostatic interaction, π-π stacking, etc., and chemical reactions include Maillard reaction, oxidation reaction, hydrolysis reaction, degradation reaction, polymerization reaction, etc. New substances and original ingredients from chemical reactions can be further activated. These effects form the basis of particle formation in the broth. The sizes of the particles in decoctions range from nanoscale to micron scale, mostly composed of polysaccharide, protein matrix, wrapped in water insoluble molecules, can increase the dispersion of insoluble components and the stability of unstable components, as well as reduce the volatile components and toxic components of volatile components, and ultimately achieve the purpose of efficient absorption and toxicity reduction. From the angle of physical change and chemical reaction in the process of decoction, this paper expounds the formation mechanism of particles in decoction, expounds the research method of particles, analyzes the components in particles and the interaction between components, and then explains the pharmacodynamic characteristics of traditional Chinese medicine decoction, which provides the foundation for the modernization of Chinese decoction.

Advance on small molecule self-assembled nano-drug delivery system / 药学学报

Since the application of biomedical nanotechnology in the field of drug delivery breathes new life into the research and development of high-end innovative agents, a substantial number of novel nano-drug delivery systems (nano-DDSs) have been successively developed and applied in the clinical practice. Among them, small molecule pure drug and prodrug-based nanoassemblies have grasped great attention, owing to the facile fabrication, ultrahigh drug loading and feasible industrial production. Herein, we provide an overview on the latest updates of small-molecule nanoassemblies. Firstly, the self-assembled prodrug-based nano-DDSs are introduced, including nanoassemblies formed by amphiphilic monomeric prodrugs, hydrophobic monomeric prodrugs and dimer monomeric prodrugs. Then, the recent advances on nanoassemblies of small molecule pure chemical drugs and biological drugs are presented. Furthermore, carrier-free small-molecule hybrid nanoassemblies of pure drugs and/or prodrugs are summarized and analyzed. Finally, the rational design, application prospects and clinical challenges of small-molecule self-assembled nano-DDSs are discussed and highlighted. This review aims to provide scientific reference for constructing the next generation of nanomedicines.

Therapeutic effect of ursodeoxycholic acid-berberine supramolecular nanoparticles on ulcerative colitis based on supramolecular system induced by weak bond / 中国中药杂志

Ulcerative colitis(UC) is a recurrent, intractable inflammatory bowel disease. Coptidis Rhizoma and Bovis Calculus, serving as heat-clearing and toxin-removing drugs, have long been used in the treatment of UC. Berberine(BBR) and ursodeoxycholic acid(UDCA), the main active components of Coptidis Rhizoma and Bovis Calculus, respectively, were employed to obtain UDCA-BBR supramolecular nanoparticles by stimulated co-decocting process for enhancing the therapeutic effect on UC. As revealed by the characterization of supramolecular nanoparticles by field emission scanning electron microscopy(FE-SEM) and dynamic light scattering(DLS), the supramolecular nanoparticles were tetrahedral nanoparticles with an average particle size of 180 nm. The molecular structure was described by ultraviolet spectroscopy, fluorescence spectroscopy, infrared spectroscopy, high-resolution mass spectrometry, and hydrogen-nuclear magnetic resonance(H-NMR) spectroscopy. The results showed that the formation of the supramolecular nano-particle was attributed to the mutual electrostatic attraction and hydrophobic interaction between BBR and UDCA. Additionally, supramolecular nanoparticles were also characterized by sustained release and pH sensitivity. The acute UC model was induced by dextran sulfate sodium(DSS) in mice. It was found that supramolecular nanoparticles could effectively improve body mass reduction and colon shortening in mice with UC(P<0.001) and decrease disease activity index(DAI)(P<0.01). There were statistically significant differences between the supramolecular nanoparticles group and the mechanical mixture group(P<0.001, P<0.05). Enzyme-linked immunosorbent assay(ELISA) was used to detect the serum levels of tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6), and the results showed that supramolecular nanoparticles could reduce serum TNF-α and IL-6 levels(P<0.001) and exhibited an obvious difference with the mechanical mixture group(P<0.01, P<0.05). Flow cytometry indicated that supramolecular nanoparticles could reduce the recruitment of neutrophils in the lamina propria of the colon(P<0.05), which was significantly different from the mechanical mixture group(P<0.05). These findings suggested that as compared with the mechanical mixture, the supramolecular nanoparticles could effectively improve the symptoms of acute UC in mice. The study provides a new research idea for the poor absorption of small molecules and the unsatisfactory therapeutic effect of traditional Chinese medicine and lays a foundation for the research on the nano-drug delivery system of traditional Chinese medicine.

Self-assembled multifunctional nanotheranostics against circulating tumor clusters in metastatic breast cancer

Circulating tumor clusters (CTC) disseminating from the primary tumor are responsible for secondary tumor formation where the conventional treatments such as chemotherapy and radiotherapy does not prevent the metastasis at locally advanced stage of breast cancer. In this study, a smart nanotheranostic system has been developed to track and eliminate the CTCs before it can colonize at a new site, which would reduce metastatic progression and increase the five-year survival rate of the breast cancer patients. Targeted multiresponsive (magnetic hyperthermia and pH) nanomicelles incorporated with NIR fluorescent superparamagnetic iron oxide nanoparticles were developed based on self-assembly for dual modal imaging and dual toxicity for spontaneous killing of CTCs in blood stream. A heterogenous tumor clusters model was developed to mimic the CTCs isolated from breast cancer patients. The nanotheranostic system was further evaluated for the targeting property, drug release kinetics, hyperthermia and cytotoxicity against developed CTC model in vitro. In vivo model in BALB/c mice equivalent to stage III and IV human metastatic breast cancer was developed to evaluate the biodistribution and therapeutic efficacy of micellar nanotheranostic system. Reduced CTCs in blood stream and low distant organ metastasis after treatment with the nanotheranostic system demonstrates its potential to capture and kill the CTCs that minimize the secondary tumor formation at distant sites.

Application of self-assembly in polypeptide drugs: a review / 生物工程学报

Self-assembly refers to the spontaneous process where basic units such as molecules and nanostructured materials form a stable and compact structure. Peptides can self-assemble by non-covalent driving forces to form various morphologies such as nanofibers, nano layered structures, and micelles. Peptide self-assembly technology has become a hot research topic in recent years due to the advantages of definite amino acid sequences, easy synthesis and design of peptides. It has been shown that the self-assembly design of certain peptide drugs or the use of self-assembled peptide materials as carriers for drug delivery can solve the problems such as short half-life, poor water solubility and poor penetration due to physiological barrier. This review summarizes the formation mechanism of self-assembled peptides, self-assembly morphology, influencing factors, self-assembly design methods and major applications in biomedical field, providing a reference for the efficient use of peptides.

Icaritin and pyropheophorbide-a self-assembled nanomedicine for enhanced the efficacy of photodynamic tumor therapy by increase the cell autophagy / 药学学报

Autophagy often occurs after cells are attacked by oxidative stress, where damaged structures are phagocytic and degraded into nutrients, thereby reducing oxidative damage, promoting the survival of cancer cells and reducing the therapeutic effect of photodynamic therapy (PDT). However, excessive activation of autophagy can promote cell apoptosis. In this paper, the photosensitizer pyropheophorbide-a (Ppa) was used to produce a large amount of reactive oxygen species (ROS) to achieve the effect of killing cancer cells. At the same time, icaritin (Ica), an autophagy inducer, was used to over-activate autophagy, which transformed the protection of cancer cells into the promotion of cancer cell apoptosis, so as to improve the effect of photodynamic therapy. In this study, the interaction force between Ica and Ppa was exploited to successfully construct a self-assembled nanomedicine IP with good stability and high drug load. The synthesis method is simple, through using the drug itself as a carrier, and the loading capacity (LA) of Ica and Ppa can be increased to 83.53% and 16.45% without introducing potential biosafety risks of nanocarriers. Compared with free Ppa, self-assembled nanomedicine IP showed superior performance in cellular uptake and reactive oxygen species production. In addition, the self-assembled nanomedicine IP can reverse the protective autophagy induced by PDT by activating the autophagy of tumor cells, and facilitate apoptosis and antitumor coordination, which significantly improves the antitumor activity of PDT.

Application of Self-assembled Nano-strategies of Traditional Chinese Medicine in Tumor Therapy： A Review / 中国实验方剂学杂志

Chinese medicine self-assembly nano-strategies（CSAN） is to utilize the self-assembly property of Chinese medicine components， so that the Chinese medicine components can self-assemble to form structurally stable nano-preparations through non-covalent interactions. The formation of Chinese medicine self-assembly nano-preparations is often a synergistic result of a variety of non-covalent interactions， and many Chinese medicine monomers are susceptible to self-assembly due to their structural characteristics， and the phenomenon of self-assembly of Chinese medicine is also common in the decoction of single or compound Chinese medicine， which has attracted the attention of researchers. It is found that CSAN can improve the solubility and bioavailability of active components in Chinese medicine， which is of positive significance for the development and application of insoluble components of Chinese medicine. The self-assembly phenomenon of Chinese medicine decoction is closely related to the therapeutic efficacy， and the study of self-assembly phenomenon of Chinese medicine will bring a new perspective for the explanation of the mechanism of Chinese medicine decoction. At the same time， traditional Chinese medicine（TCM） has unique advantages in the field of anti-tumor. The application of CSAN in the field of oncology can not only exert the anti-tumor effect of the active components of Chinese medicine directly， but also act as a natural nano-carrier to carry chemotherapy drugs for combination chemotherapy， improve the targeting of drugs， enhance the anti-tumor efficacy， and reduce the side effects of chemotherapy， which has excellent anti-tumor potential. The preparation method of Chinese medicine self-assembly nano-preparations is simple， low cost， and has better safety than traditional nano-preparations， which is conducive to the promotion of the clinical transformation of nano-preparations， and also helps to provide new strategies and perspectives for promoting the modernization of TCM. Therefore， based on a large number of researches in this field in recent years， this paper reviewed the formation mechanism， different assembly forms， formation conditions and stability of Chinese medicine self-assembly nano-preparations by searching databases such as China national knowledge infrastructure（CNKI）， PubMed， WanFang data and VIP， and summarized the application of CSAN in different tumor therapies， providing a reference for further research on CSAN.

Membrane dual-targeting probes: A promising strategy for fluorescence-guided prostate cancer surgery and lymph node metastases detection

Fluorescence-guided surgery (FGS) with tumor-targeted imaging agents, particularly those using the near-infrared wavelength, has emerged as a real-time technique to highlight the tumor location and margins during a surgical procedure. For accurate visualization of prostate cancer (PCa) boundary and lymphatic metastasis, we developed a new approach involving an efficient self-quenched near-infrared fluorescence probe, Cy-KUE-OA, with dual PCa-membrane affinity. Cy-KUE-OA specifically targeted the prostate-specific membrane antigen (PSMA), anchored into the phospholipids of the cell membrane of PCa cells and consequently showed a strong Cy7-de-quenching effect. This dual-membrane-targeting probe allowed us to detect PSMA-expressing PCa cells both in vitro and in vivo and enabled clear visualization of the tumor boundary during fluorescence-guided laparoscopic surgery in PCa mouse models. Furthermore, the high PCa preference of Cy-KUE-OA was confirmed on surgically resected patient specimens of healthy tissues, PCa, and lymph node metastases. Taken together, our results serve as a bridge between preclinical and clinical research in FGS of PCa and lay a solid foundation for further clinical research.

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.

Construction and in vitro evaluation of AIE self-assembled probe based on GSH response covalent cyclization / 国际生物医学工程杂志

Objective:To construct an aggregation induced emission (AIE) self-assembled probe based on glutathione (GSH) response covalent cyclization and evaluate it in vitro.Methods:The peptide sequence containing the 2-cyano-6-aminobenzothiazole-cysteine (CBT-Cys) condensation sequence was synthesized by the solid-phase peptide synthesis method. After coupling with an AIE molecule by click chemical reaction, an AIE self-assembled probe 1 based on GSH response covalent cyclization was constructed, and probe 2 lacking Cys structure was used as the control. The absorption and emission spectra of probes were tested and the specificity of probes to GSH was analyzed. The hydrodynamic diameter and structure of the probes after response were compared. The effects of different pH values, temperatures, probe concentrations, and GSH concentrations on fluorescence intensity were investigated. The toxicity of probes to tumor cells such as HeLa, HepG2 and MDA-MB-231 was evaluated.Results:After GSH response, the fluorescence of probe 1 was enhanced by about 6 times and that of probe 2 was enhanced by about 2 times; probe 1 was converted into a dimer with a hydrodynamic diameter of about 896.1 nm. Probe 2 lacked a cyclization motif and was converted into a monomer with a hydrodynamic diameter of about 427.4 nm. The fluorescence intensity of probe 1 was significantly higher than that of probe 2 at pH=7.0 and 37 ℃, and the toxicity of probes to tumor cells (HeLa, HepG2 and MDA-MB-231) was low.Conclusions:After the disulfide bond of probe 1 was reduced by GSH, the probe molecule lost the hydrophilic sequence, resulting in fluorescence turn-on (the first aggregation), and probe 1 immediately generates an AIE dimer (the second aggregation) because it contains a CBT-Cys cyclization sequence, which realizes the dual AIE effect compared with the single aggregation of probe 2, and significantly enhances the fluorescence emission. Probe 1 has better applicability in physiological environments, which provides an idea for in-situ generation of covalent cycling probes in vivo and is expected to be used in tumor imaging and treatment in the later stages.

Preparação e caracterização de nanocarreadores de beta-lactose à base de pectina e lisozima / Preparation and characterization of beta-lactose nanocarriers based on pectin and lysozyme

O objetivo deste trabalho foi preparar e caracterizar nanocarreadores via auto-organização a partir da pectina de citros e lisozima para o encapsulamento da ß-lactose. Foram estudadas três condições de interação entre os biopolímeros variando a razão molar pectina/lisozima (3:1, 2:1, 1:1, 1:2 e 1:3), o pH e o tempo de aquecimento. A confirmação da interação foi determinada por espectroscopia no infravermelho por transformada de Fourier (FTIR) e por calorimetria de varredura diferencial (DSC). Os espectros de infravermelho evidenciaram que ligações de hidrogênio foram as principais forças envolvidas na formação dos nanocarreadores e sugeriram a ausência de ß-lactose livre na superfície das nanopartículas. Os termogramas evidenciaram que as nanopartículas formadas na presença de ß-lactose têm maior estabilidade térmica do que as nanopartículas sem ß-lactose. Para ambas as formulações estudadas, na presença e na ausência de ß-lactose, a formação das nanopartículas ocorreu entre os valores de pKa e ponto isoelétrico (pI) da pectina e lisozima, respectivamente, sendo a melhor razão de interação pectina/lisozima 1:2, em pH 10, a 80 ºC por 30 min. As nanopartículas foram formadas via auto-organização e todos as partículas apresentaram distribuição de tamanho homogênea, formato esférico, diâmetro inferior a 100 nm e carga superficial negativa. A morfologia e o tamanho das partículas pouco alteraram com a incorporação da -lactose. A eficiência de encapsulação (EE) da ß-lactose foi superior a 96% para as concentrações estudadas. Ensaios preliminares in vitro, em células epiteliais de câncer de cólon (HCT-116), evidenciaram que as nanopartículas formadas são capazes de adentrar no meio intracelular, possivelmente, por via endocitose

This work aimed to prepare and characterize nanocarriers via self-assembly using citrus pectin and lysozyme for ß-lactose encapsulation. Three interaction conditions between the biopolymers were studied, varying the pectin/lysozyme molar ratio (3:1, 2:1, 1:1, 1:2 and 1:3), pH and heating time. Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) determined the interaction's confirmation. The infrared spectra showed that hydrogen bonds were the main forces involved in the formation of nanocarriers and suggested the absence of free ß-lactose on the surface of the nanoparticles. The thermograms showed that nanoparticles formed in the presence of ß-lactose have greater thermal stability than nanoparticles without ß-lactose. For both formulations studied, in the presence and absence of lactose, the formation of nanoparticles occurred between the pKa and isoelectric point (pI) values of pectin and lysozyme, respectively, with the best pectin/lysozyme interaction molar ratio 1:2, at pH 10, at 80 °C for 30 min. Nanoparticles were formed via self-assembly, and all particles presented homogeneous size distribution, spherical shape, diameter less than 100 nm, and negative surface charge. The morphology and size of the particles changed little with the incorporation of ß-lactose. The encapsulation efficiency (EE) of ß-lactose was higher than 96% for the concentrations studied. Preliminary in vitro assays in colon cancer epithelial cells (HCT-116) showed that the nanoparticles formed are capable of entering the intracellular medium, possibly via endocytosis

Enzyme-instructed and mitochondria-targeting peptide self-assembly to efficiently induce immunogenic cell death

Immunogenic cell death (ICD) plays a major role in cancer immunotherapy by stimulating specific T cell responses and restoring the antitumor immune system. However, effective type II ICD inducers without biotoxicity are still very limited. Herein, a tentative drug- or photosensitizer-free strategy was developed by employing enzymatic self-assembly of the peptide F-pY-T to induce mitochondrial oxidative stress in cancer cells. Upon dephosphorylation catalyzed by alkaline phosphatase overexpressed on cancer cells, the peptide F-pY-T self-assembled to form nanoparticles, which were subsequently internalized. These affected the morphology of mitochondria and induced serious reactive oxygen species production, causing the ICD characterized by the release of danger-associated molecular patterns (DAMPs). DAMPs enhanced specific immune responses by promoting the maturation of DCs and the intratumoral infiltration of tumor-specific T cells to eradicate tumor cells. The dramatic immunotherapeutic capacity could be enhanced further by combination therapy of F-pY-T and anti-PD-L1 agents without visible biotoxicity in the main organs. Thus, our results revealed an alternative strategy to induce efficient ICD by physically promoting mitochondrial oxidative stress.

Molecular interactions between the main components of Shuanghuanglian injection and ciprofloxacin injection based on self-assembly / 药学学报

The combination of Shuanghuanglian injection (SHLI) and ciprofloxacin injection (CIPI) is frequently prescribed in clinical practice, but the basis for the combination is weak. In this study, isothermal titration calorimetry and ultraviolet-visible absorption spectrometry were applied to identify the molecular interactions of SHLI and its main components, chlorogenic acid and neochlorogenic acid with CIPI. Scanning electron microscopy, Fourier-transform infrared spectroscopy, and cold-spray ionization mass spectrometry were performed to confirm that this molecular interaction was related to the formation of self-assembled supramolecular systems induced by chlorogenic acid and neochlorogenic acid with CIPI through weak intermolecular bonds. The antibacterial activity toward Pseudomonas aeruginosa (P. aeruginosa) was evaluated via molecular interactions, and the inhibitory ability of SHLI, chlorogenic acid and neochlorogenic acid against P. aeruginosa was significantly reduced after interaction with CIPI. A molecular docking study demonstrated that the reduced antibacterial ability was closely related to the competitive binding of drug molecules to the same binding site of the DNA gyrase B (GyrB) subunit of P. aeruginosa. The present study uncovered the intermolecular interactions of SHLI and its main components chlorogenic acid and neochlorogenic acid with CIPI from the perspective of molecular self-assembly and contribute to the reduction of its antibacterial ability, providing a basis for the clinical combination of SHLI and CIPI.

Peptide-based bioactivated in vivo assembly nanomaterials and its biomedical applications: a review / 生物工程学报

Based on the self-assembly process occurring in the human body all the time, self-assembled nanomaterials were designed by the researchers. The self-assembled nanomaterials have controllability, biocompatibility and functional advantages in vivo. The self-assembled nanomaterials constructed in situ under a physiological environment display various biological characteristics which can be used for imaging, therapy, and broad clinical applications. In situ self-assembled nanomaterials can boost drug function, reduce toxic and side effects, prolong imaging time and enlarge signal-to-noise ratio. By using pathological conditions to trigger specific responses in vivo, well-ordered nanoaggregates can be spontaneously formed by multiple weak bonding interactions. The assembly shows higher accumulation and longer retention in situ. Endogenous triggers for in situ assembly, such as enzymes, pH, reactive oxygen species and ligand receptor interaction, can be used to transform the materials into a variety of controllable nanostructures including nanoparticles, nanofibers and gels through bioactivated in vivo assembly (BIVA) strategies. BIVA strategies can be applied for treatment, imaging or participate in the physiological activities of cells at the lesion site. This review summarized and prospected the design of self-assembled peptide materials based on BIVA technology and their biomedical applications. The nanostructures of the self-assembly enable some beneficial biological effects, such as assembly induced retention (AIR) effect, enhanced targeting effect, multivalent bond effect, and membrane disturbance. Thus, the BIVA nanotechnology is promising for efficient drug delivery, enhancement of targeting and treatment, as well as optimization of the biological distribution of drugs.

Advances in self-assembled peptide hydrogels for bone regeneration / 中国药科大学学报

@#The development of osteoinductive bone-filling biomaterials for bone regeneration is of great significance.Self-assembled peptide hydrogels with high biomimetic extracellular matrix structure, low immunogenicity, easy synthesis and modification, and flexible loading capacity provide a highly efficient therapeutic platform for bone tissue repair.Herein, we discuss the design principles of self-assembled peptide hydrogels, report the structural characteristics and assembly mechanisms of self-assembled peptides, and highlight recent advances in self-assembled peptide hydrogels for bone regeneration, including delivery to cells , bone morphogenetic proteins, active factors and small molecular substances.Finally, the bottleneck and development direction of self-assembled peptide hydrogels are pointed out, aiming to provide guidance for the construction of hydrogel delivery systems with high osteogenic properties.

Self-assembling, pH-responsive nanoflowers for inhibiting PAD4 and neutrophil extracellular trap formation and improving the tumor immune microenvironment

Self-assembling carrier-free nanodrugs are attractive agents because they accumulate at tumor by an enhanced permeability and retention (EPR) effect without introduction of inactive substances, and some nanodrugs can alter the immune environment. We synthesized a peptidyl arginine deiminase 4 (PAD4) molecular inhibitor, ZD-E-1M. It could self-assembled into nanodrug ZD-E-1. Using confocal laser scanning microscopy, we observed its cellular colocalization, PAD4 activity and neutrophil extracellular traps (NETs) formation. The populations of immune cells and expression of immune-related proteins were determined by single-cell mass cytometry. ZD-E-1 formed nanoflowers in an acidic environment, whereas it formed nanospheres at pH 7.4. Accumulation of ZD-E-1 at tumor was pH-responsive because of its pH-dependent differences in the size and shape. It could enter the nucleus and bind to PAD4 to prolong the intracellular retention time. In mice, ZD-E-1 inhibited tumor growth and metastasis by inhibiting PAD4 activity and NETs formation. Besides, ZD-E-1 could regulate the ratio of immune cells in LLC tumor-bearing mice. Immunosuppressive proteins like LAG3 were suppressed, while IFN-γ and TNF-α as stimulators of tumor immune response were upregulated. Overall, ZD-E-1 is a self-assembling carrier-free nanodrug that responds to pH, inhibits PAD4 activity, blocks neutrophil extracellular traps formation, and improves the tumor immune microenvironment.

Pharmaceutical applications of framework nucleic acids

DNA is a biological polymer that encodes and stores genetic information in all living organism. Particularly, the precise nucleobase pairing inside DNA is exploited for the self-assembling of nanostructures with defined size, shape and functionality. These DNA nanostructures are known as framework nucleic acids (FNAs) for their skeleton-like features. Recently, FNAs have been explored in various fields ranging from physics, chemistry to biology. In this review, we mainly focus on the recent progress of FNAs in a pharmaceutical perspective. We summarize the advantages and applications of FNAs for drug discovery, drug delivery and drug analysis. We further discuss the drawbacks of FNAs and provide an outlook on the pharmaceutical research direction of FNAs in the future.