Rationally designed ß-cyclodextrin-crosslinked polyacrylamide hydrogels for cell spheroid formation and 3D tumor model construction.

In vitro tumor models are essential for understanding tumor behavior and evaluating tumor biological properties. Hydrogels that can mimic the tumor extracellular matrix have become popular for creating 3D in vitro tumor models. However, designing biocompatible hydrogels with appropriate chemical and physical properties for constructing tumor models is still a challenge. In this study, we synthesized a series of ß-cyclodextrin (ß-CD)-crosslinked polyacrylamide hydrogels with different ß-CD densities and mechanical properties and evaluated their potential for use in 3D in vitro tumor model construction, including cell capture and spheroid formation. By utilizing a combination of ß-CD-methacrylate (CD-MA) and a small amount of N,N'-methylene bisacrylamide (BIS) as hydrogel crosslinkers and optimizing the CD-MA/BIS ratio, the hydrogels performed excellently for tumor cell 3D culture and spheroid formation. Notably, when we co-cultured L929 fibroblasts with HeLa tumor cells on the hydrogel surface, co-cultured spheroids were formed, showing that the hydrogel can mimic the complexity of the tumor extracellular matrix. This comprehensive investigation of the relationship between hydrogel mechanical properties and biocompatibility provides important insights for hydrogel-based in vitro tumor modeling and advances our understanding of the mechanisms underlying tumor growth and progression.

[Material basis of Rhei Radix et Rhizoma-Coptidis Rhizoma combination in alleviating "bitter-cold" properties based on supramolecular chemistry of Chinese medicine].

The present study aimed to explore the material basis of Rhei Radix et Rhizoma-Coptidis Rhizoma combination in alleviating "bitter-cold" properties based on the supramolecular chemistry of Chinese medicine.Dynamic light scattering and scanning/transmission electron microscopy were used to characterize the morphological characteristics of supramolecules in the decoction of Rhei Radix et Rhizoma and Coptidis Rhizoma.The chemical composition of supramolecules, as well as the dissolution and release processes of supramolecules and the medicinal components of Coptidis Rhizoma decoction, was determined by the high-performance liquid chromatography-mass spectrometry.The differences in "bitter-cold" medicinal properties between Rhei Radix et Rhizoma decoction, Coptidis Rhizoma decoction, and co-decoction were analyzed by sensory evaluation, electronic tongue, mouse diarrhea model, and pathological indicators.The anthraquinones/tannins and alkaloids interacted to form supramolecules with a scale of about 400 nm when Rhei Radix et Rhizoma and Coptidis Rhizoma were decocted together, which delayed the dissolution and release of the active components represented by berberine. Compared with the consequence of single drug administration at 4 g·kg~(-1), the combination of the two drugs at 8 g·kg~(-1) significantly alleviated the "bitter-cold" properties.The effective components interacted to form supramolecules in the co-decoction of Rhei Radix et Rhizoma and Coptidis Rhizoma, which affected the dissolution and release of the effective components of Chinese medicinal decoction, thereby alleviating the "bitter-cold" properties.The findings of this study provide a new idea for revealing the scientific compatibility of Rhei Radix et Rhizoma and Coptidis Rhizoma.

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

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

Combined photothermal-immunotherapy via poly-tannic acid coated PLGA nanoparticles for cancer treatment.

Photothermal therapy (PTT) is able to ablate tumors via hyperthermia, while immunotherapy could prevent tumor recurrence and metastasis by activating the host immune responses. Therefore, the combination of PTT and immunotherapy offers great advantages for the treatment of cancer. To achieve this goal, poly tannic acid (pTA) coated PLGA nanoparticles (PLGA-pTA NPs) were synthesized for combined photothermal-immunotherapy. pTA was a coordination complex formed by TA and Fe3+ and it could be easily coated on PLGA NPs within seconds with a coating rate of 5.89%. As a photothermal agent, PLGA-pTA revealed high photothermal conversion efficiency and excellent photo-stability upon 808 nm laser irradiation. It also exhibited strong photothermal cytotoxicity against 4T1 cells. Moreover, PLGA-pTA based PTT could effectively trigger DC maturation since it could induce the release of DAMPs. The result of animal experiments showed that PLGA-pTA plus laser irradiation raised the tumor temperature up to ca. 60 °C and effectively suppressed the growth of primary tumors. What's more, the progression of distant tumors as well as lung metastasis was also significantly inhibited due to the activation of anti-tumor responses by PLGA-pTA mediated PTT. When further combined with anti-PD-L1 antibody (a-PD-L1), the tumor growth and metastasis were almost completely inhibited. Our study provided a versatile platform to achieve combined photothermal-immunotherapy with enhanced therapeutic efficacy.

Berberine-Based Heterogeneous Linear Supramolecules Neutralized the Acute Nephrotoxicity of Aristolochic Acid by the Self-Assembly Strategy.

Aristolochic acid (AA) has been reported to cause a series of health problems, including aristolochic acid nephropathy and liver cancer. However, AA-containing herbs are highly safe in combination with berberine (Ber)-containing herbs in traditional medicine, suggesting the possible neutralizing effect of Ber on the toxicity of AA. In the present study, in vivo systematic toxicological experiments performed in zebrafish and mice showed that the supramolecule self-assembly formed by Ber and AA significantly reduced the toxicity of AA and attenuated AA-induced acute kidney injury. Ber and AA can self-assemble into linear heterogenous supramolecules (A-B) via electrostatic attraction and π-π stacking, with the hydrophobic groups outside and the hydrophilic groups inside during the drug combination practice. This self-assembly strategy may block the toxic site of AA and hinder its metabolism. Meanwhile, A-B linear supramolecules did not disrupt the homeostasis of gut microflora as AA did. RNA-sequence analysis, immunostaining, and western blot of the mice kidney also showed that A-B supramolecules almost abolished the acute nephrotoxicity of AA in the activation of the immune system and tumorigenesis-related pathways.

Synergistic Effect of Berberine-Based Chinese Medicine Assembled Nanostructures on Diarrhea-Predominant Irritable Bowel Syndrome In Vivo.

Diarrhea-predominant irritable bowel syndrome (IBS-D) is one common chronic functional disease of the digestive system with limited treatments. The microbiota-gut-brain axis (MGBA) has a central function in the pathogeny of IBS-D, which includes the participation of many various factors, such as brain-gut peptides (BGPs), immune inflammation, and intestinal flora. Inspired by the drug combination in traditional Chinese medicine (TCM), our previous study discovered that berberine (BBR) and baicalin (BA) could form natural self-assemblies as BA-BBR nanoparticles (BA-BBR NPs) and showed synergistic effects against IBS-D. Here, we investigated the synergistic effects of BA-BBR NPs on IBS-D model mice induced by chronic restraint stress plus Senna alexandrina Mill decoction with the influence on MGBA. BA-BBR NPs showed the best therapeutic effect on improving visceral hypersensitivity and diarrhea on IBS-D model mice, compared with BBR, BA, and BA/BBR mixture. Furthermore, BA-BBR NPs significantly (P<0.05) reduced the levels of 5-hydroxytryptamine (5-HT), vasoactive intestinal polypeptide (VIP) and choline acety transferase (CHAT) in colon tissues or of serum from BGPs; it lowered the expressions of the nuclear factor kappa-B (NF-κB) in colon tissues and changed the levels of basophil granulocyte (BASO) and leukomonocyte (LYMPH) in whole blood from immune inflammation; it altered the intestinal flora of Bacteroidia, Deferribacteres, Verrucomicrobia, Candidatus_Saccharibacteria, and Cyanobacteria from intestinal flora. In conclusion, BA-BBR NPs, after forming the natural self-assembly between BBR and BA, promoted the synergistic effect on IBS-D mice than the sum of BBR and BA effects, based to the formation of self-assemblies rather than the simple mixing. It further proved that synergistic effect of BA-BBR NPs on IBS-D mice might be related to BGPs, immune inflammation, and intestinal flora from three important interrelated components of MGBA. This study will provide a novel idea for the interpretation of TCM compatibility theory and provide the basis for BA-BBR NPs as a medicinal plant-derived natural and efficient nanomaterial for clinical use.

Betulinic Acid-Nitrogen Heterocyclic Derivatives: Design, Synthesis, and Antitumor Evaluation in Vitro.

Betulinic acid (BA) is a star member of the pentacyclic triterpenoid family, which exhibits great prospects for antitumor drug development. In an attempt to develop novel antitumor candidates, 21 BA-nitrogen heterocyclic derivatives were synthetized, in addition to four intermediates, 23 of which were first reported. Moreover, they were screened for in-vitro cytotoxicity against four tumor cell lines (Hela, HepG-2, BGC-823 and SK-SY5Y) by a standard methylthiazol tetrazolium (MTT) assay. The majority of these derivatives showed much stronger cytotoxic activity than BA. Remarkably, the most potent compound 7e (the half maximal inhibitory concentration (IC50) of which was 2.05 ± 0.66 µM) was 12-fold more toxic in vitro than BA-treated Hela. Furthermore, multiple fluorescent staining techniques and flow cytometry collectively revealed that compound 7e could induce the early apoptosis of Hela cells. Structure-activity relationships were also briefly discussed. The present study highlighted the importance of introducing nitrogen heterocyclic rings into betulinic acid in the discovery and development of novel antitumor agents.