Supramolecular nanofiber of indomethacin derivative confers highly cyclooxygenase-2 (COX-2) selectivity and boosts anti-inflammatory efficacy

Recent Advances in the Application of Hydrogels as Drug Carriers in Inflammatory Bowel Disease: A Review

Inflammatory bowel disease (IBD) is a chronic and refractory disease with increasing incidence, adversely impacting millions of patients worldwide. Current therapeutic strategies for IBD often exhibit considerable adverse effects, limited efficacy, and a high tendency for recurrence, highlighting the urgent need for novel therapeutic agents. Hydrogel, a three-dimensional hydrophilic network polymer material known for its excellent biocompatibility and responsiveness to stimuli, has been effectively utilized as a drug carrier across various therapeutic systems. The hydrogels' application in IBD treatment holds significant promise for enhancing therapeutic outcomes. This review synthesizes recent advancements in leveraging hydrogels as drug carriers for IBD management. The discussion encompasses the response mechanisms of hydrogels, their application in IBD therapy, and methods of administration. As drug delivery matrices, hydrogels exhibit considerable potential for treating IBD.

A One Stone Three Birds Paradigm of Photon-Driven Pyroptosis Dye for Amplifying Tumor Immunotherapy

Activating the pyroptosis pathway of tumor cells by photodynamic therapy (PDT) for immunogenic cell death (ICD) is considered a valid strategy in pursuit of antitumor immunotherapy, but it remains a huge challenge due to the lack of reliable design guidelines. Moreover, it is often overlooked that conventional PDT can exacerbate the development of tumor immunosuppressive microenvironment, which is apparently unfavorable to clinical immunotherapy. The endoplasmic reticulum's (ER) pivotal role in cellular homeostasis and its emerging link to pyroptosis have galvanized interest in ER-centric imaging and therapeutics. Herein, using the targeted group-assisted strategy (TAGS), an intriguing cyclooxygenase-2-targeted photodynamic conjugate, Indo-Cy, strategically created, which exploits the enzyme's overabundance in the tumoral ER, especially under proinflammatory hypoxic conditions. This conjugate, with its highly precise ER imaging, embodies a trifunctional strategy: i) innovating an electron transfer mechanism, converting the hemicyanine moiety into an oxygen-independent type I photosensitizer, thereby navigating around the hypoxia constraints of traditional PDT; ii) executing precise ER-targeted PDT, amplifying caspase-1/GSDMD-mediated pyroptosis for ICD; 3) attenuating immunosuppressive pathways by inhibiting cyclooxygenase-2 downstream factors, including HIF-1α, PGE2, and VEGF. Indo-Cy's multimodal approach potently induces in vivo tumor pyroptosis and bolsters antitumor immunity, underscoring cyclooxygenase-2-targeted dyes' potential as a versatile oncotherapeutics.

Mitochondrial Localization of Antioxidant Nanodrug Suppresses Ocular Inflammation by Alleviating Oxidative Stress on Cells

External environments (e. g., pollutants, irritants, ultraviolet radiation, etc) probably activate oxidative stress on the ocular surface, further leading to inflammatory responses and cellular apoptosis. For treating ophthalmic diseases, one of the strategies is to regulate oxidative stress through antioxidants. Here we conjugate a polyphenolic antioxidant drug (i. e., caffeic acid) with a small peptide of protein tag to generate a peptide-drug conjugate as a nanodrug. With a self-assembled ability to form nanoparticles, the nanodrug mainly enters human corneal epithelial cells (HCEC) by caveolin-mediated endocytosis, succeeds lysosomal escape, and achieves mitochondrial localization of caffeic acid. Revealed by free radical scavenging experiments, the nanodrug shows considerable antioxidant capacities. In mouse leukemia cells of monocyte macrophage (RAW 264.7) induced by lipopolysaccharide (LPS), the nanodrug inhibits various pro-inflammatory cytokines (e. g., NO, IL-6, and TNF-α) by up-regulating the expression of anti-apoptotic protein (e. g., Bcl-2). As an investigation of alleviating oxidative stress by the mitochondrial localization of antioxidant, this work may establish an experimental foundation for the regulation of cellular redox balance, as well as provide different insights for the clinical development of antioxidant drug delivery systems in the treatment of ocular disease.

NaCl-Responsive Ultrashort Peptide to Trigger Self-Assembly of TPE-Capped Supramolecular Hydrogelator

With the advantages of less invasiveness and better shape adaptability, in situ-forming hydrogels are desired biomaterials as scaffolds, drug carriers, and so on. Herein, a negatively charged NaCl-responsive ultrashort peptide sequence (EEH) is reported whose electrostatic repulsion can be reduced through the charge-shielding effect. Under physiological conditions, its AIEgen-capped amphiphile TPE-GEEH of low concentration (1 mg/mL) presents NaCl-triggered morphological transformation from micelle to closely packed fiber with enhanced emission, which can be applied to biosense sodium ion (Na+) with high sensitivity and quick response. At a slightly acidic pH, 10 mg/mL TPE-GEEH undergoes sol-gel transition upon addition of NaCl (100 mM) with improved mechanical properties, which should be useful to develop an in situ-forming hydrogel. Overall, our report provides a simple strategy to construct NaCl-responsive assemblies for potential application in biosensors and drug delivery system.

Leveraging supramolecular systems in biomedical breakthroughs

Supramolecular systems, intricate assemblies of molecular subunits organized through various intermolecular interactions, offer versatile platforms for diverse applications, including gene therapy, antimicrobial therapy, and cellular engineering. These systems are cost-effective and environmentally friendly, contributing to their attractiveness in biomaterial design. Furthermore, supramolecular biomaterials based on acyclic, macrocyclic compounds and lipid-based assembly offer potential applications in distinct types of biomedical approaches. In this context, they can transport several therapeutic agents very effectively to the target site. Supramolecular hydrogels exhibit potent antimicrobial activity by disrupting microbial membranes, offering promising solutions to combat drug-resistant pathogens. Additionally, supramolecular luminescent nanoparticles enable targeted cell imaging, facilitating disease diagnosis and treatment with high specificity and sensitivity. In cellular engineering, supramolecular assemblies of small molecules demonstrate biological activities, overcoming challenges in cancer treatment by inhibiting signaling pathways and inducing apoptosis in cancer cells. This review emphasizes the applications of supramolecular systems from gene therapy to cellular imaging, tissue engineering, and antimicrobial therapy, showcasing their potential to drive innovation and address pressing healthcare challenges.

A supramolecular hydrogel eye-drop alleviates inflammation via clathrin-mediated endocytosis

The modulation of inflammation is effective to treat many ocular surface diseases. Thus the low bioavailability of common anti-inflammatory eye-drops urges the development of ocular drug delivery systems to extend the ocular retention and enhance the cellular uptake for improving anti-inflammatory effect of eye-drops. Here we covalently conjugate two molecules of clinically anti-inflammatory drug (i.e., dexamethasone) with a small peptide (i.e., Tyr-Glu-Asn-Pro-Thr-Tyr) to generate an anti-inflammatory hydrogel eye-drop. With a self-assembled ability, the designed supramolecular hydrogel achieves gel-sol-gel transition by varying shearing forces which increases the pre-corneal retention of drug. The fluorescent imaging reveals the efficient cellular uptake of designed conjugate via clathrin-mediated endocytosis. A rodent model of endotoxin-induced uveitis verifies that the supramolecular hydrogel eye-drop suppresses inflammation responses without ocular irritation. As a rational approach to design anti-inflammatory drugs as eye-drops, this work overcomes the frequent instillation of clinical eye-drops and further improves the bioavailability of anti-inflammatory drugs, which may provide an effective and household way to fight ocular surface inflammation.

Phe-Phe-Based Macroscopic Supramolecular Hydrogel Construction Strategies and Biomedical Applications

Since the phenylalanine (Phe) dipeptide moiety is referred to as an essential structure for building amyloid-β peptide from Alzheimer's disease, its wonderful assembly ability to form nanofibers has been extensively studied. Cross-linked Phe-Phe-based peptide nanofibers can construct networks, thus encapsulating the drugs to form supramolecular hydrogels. Recently, scientists have proposed a variety of Phe-Phe-based macroscopic supramolecular hydrogels and used them in biomedical applications. Therefore, we summarize the construction strategies of Phe-Phe-based macroscopic supramolecular hydrogels and list their represented biomedical applications (e.g., wound healing, eye protection, cancer therapy, etc.) since the birth of Phe-Phe-based supramolecular hydrogels. In addition, we present the perspectives and challenges of Phe-Phe-based macroscopic peptide hydrogels.

Combined transcriptome and metabolome analysis reveals the toxic effects of antimony on the earthworm

Antimony (Sb) poses a significant ecological threat. This study combines biochemical, pathological, transcriptome, and metabolome analyses to assess the short-term (14-day) toxic impact of two Sb levels (25 mg/kg and 125 mg/kg) on earthworms (Eisenia fetida). Higher Sb concentration caused severe intestinal damage, elevated metallothionein (MT) levels, and reduced antioxidant capacity. Metabolome analysis identifies 404 and 1698 significantly differential metabolites in the two groups. Metabolites such as S(-)-cathinone, N-phenyl-1-naphthylamine, serotonin, 4-hydroxymandelonitrile, and 5-fluoropentylindole contributed to the metabolic responses to Sb stress. Transcriptome analysis shows increased chitin synthesis as a protective response, impacting amino sugar and nucleotide sugar metabolism for cell wall synthesis and damage repair. Integrated analysis indicated that 5 metabolite-gene pairs were found in two Sb levels and 11 enriched pathways were related to signal transduction, carbohydrate metabolism, immune system, amino acid metabolism, digestive system, and nervous system. Therefore, the integration of multiomics approaches enhanced our comprehension of the molecular mechanisms underlying the toxicity of Sb in E. fetida.

Computational Molecular Docking and Simulation-Based Assessment of Anti-Inflammatory Properties of Nyctanthes arbor-tristis Linn Phytochemicals

The leaves, flowers, seeds, and bark of the Nyctanthes arbor-tristis Linn plant have been pharmacologically evaluated to signify the medicinal importance traditionally described for various ailments. We evaluated the anti-inflammatory potentials of 26 natural compounds using AutoDock 4.2 and Molecular Dynamics (MDS) performed with the GROMACS tool. SwissADME evaluated ADME (adsorption, distribution, metabolism, and excretion) parameters. Arb_E and Beta-sito, natural compounds of the plant, showed significant levels of binding affinity against COX-1, COX-2, PDE4, PDE7, IL-17A, IL-17D, TNF-α, IL-1β, prostaglandin E2, and prostaglandin F synthase. The control drug celecoxib exhibited a binding energy of -9.29 kcal/mol, and among the tested compounds, Arb_E was the most significant (docking energy: -10.26 kcal/mol). Beta_sito was also observed with high and considerable docking energy of -8.86 kcal/mol with the COX-2 receptor. COX-2 simulation in the presence of Arb_E and control drug celecoxib, RMSD ranged from 0.15 to 0.25 nm, showing stability until the end of the simulation. Also, MM-PBSA analysis showed that Arb_E bound to COX-2 exhibited the lowest binding energy of -277.602 kJ/mol. Arb_E and Beta_sito showed interesting ADME physico-chemical and drug-like characteristics with significant drug-like effects. Therefore, the studied natural compounds could be potential anti-inflammatory molecules and need further in vitro/in vivo experimentation to develop novel anti-inflammatory drugs.