High-resolution neuraminidase inhibition profiling of Arnebia euchroma (Royle) I.M. Johnst. based on HR-MS and target isolation: An example study of anti-infectious constituents in traditional Chinese medicine

Arnebinfuranoids A-G, seven unique heterodimers of meroterpenoids from Arnebia euchroma

Seven previously undescribed heterodimers (1-7) with unusual carbon-carbon bond linkages for monomeric meroterpenoids and a known compound (8) were isolated from the roots of Arnebia euchroma (Royle) Johnst. Their structures were elucidated by extensive spectroscopic methods and quantum chemical calculations of electronic circular dichroism spectra. Further careful NMR analysis revealed that the chemical shift differences of the methylene protons affected by remote chirality were related to the relative configurations of the heterodimers (1-6). Compounds 2-5 and 8 significantly ameliorated PC12 cell damage induced by H2O2 and glutamate in vitro comparable to edaravone.

A Systematic Review on Biochemical Perspectives on Natural Products in Wound Healing: Exploring Phytochemicals in Tissue Repair and Scar Prevention

Wound healing is a critical process in tissue repair following injury, and traditional herbal therapies have long been utilized to facilitate this process. This review delves into the mechanistic understanding of the significant contribution of pharmacologically demonstrated natural products in wound healing. Natural products, often perceived as complex yet safely consumed compared to synthetic chemicals, play a crucial role in enhancing the wound-healing process. Drawing upon a comprehensive search strategy utilizing databases such as PubMed, Scopus, Web of Science, and Google Scholar, this review synthesizes evidence on the role of natural products in wound healing. While the exact pharmacological mechanisms of secondary metabolites in wound healing remain to be fully elucidated, compounds from alkaloids, phenols, terpenes, and other sources are explored here to delineate their specific roles in wound repair. Each phytochemical group exerts distinct actions in tissue repair, with some displaying multifaceted roles in various pathways, potentially enhancing their therapeutic value, supported by reported safety profiles. Additionally, these compounds exhibit promise in the prevention of keloids and scars. Their potential alongside economic feasibility may propel them towards pharmaceutical product development. Several isolated compounds, including chlorogenic acid, thymol, and eugenol from natural sources, are undergoing investigation in clinical trials, with many reaching advanced stages. This review provides mechanistic insights into the significant role of pharmacologically demonstrated natural products in wound healing processes.

A class of geranylquinol-derived polycyclic meroterpenoids from Arnebia euchroma against heart failure by reducing excessive autophagy and apoptosis in cardiomyocytes

Ten new B-ring aromatized 6/6/6-tricyclic dearomatized benzocogeijerene-based meroterpenoids with unusual methyl 1,2-shift or demethylation (2-9b), and two new geranylquinol derivatives (1 and 10), together with two known compounds (11 and 12), were isolated from the roots of Arnebia euchroma. Their structures were elucidated by extensive spectroscopic methods, X-ray diffraction crystallography, and ECD calculations. The plausible biosynthetic pathways including the unusual methyl 1,2-shfit and demethylation for B-ring aromatized 6/6/6-tricyclic meroterpenoids were discussed. Compounds 1, 2, 5, 6, 11, and 12 showed significant cardioprotective activities comparable to diltiazem against isoprenaline (ISO)-induced H9C2 cell damage in vitro. Compound 11 probably exerted heart-protective effect on ISO-induced H9C2 cells by modulating the PI3K-AKT-mTOR pathway, reducing excessive autophagy, and decreasing myocardial apoptosis.

Inhibitory and preventive effects of Arnebia euchroma (Royle) Johnst. root extract on Streptococcus mutans and dental caries in rats

BACKGROUND

Dental caries is one of the prevalent conditions that threaten oral health. Arnebia euchroma (Royle) Johnst. root (AR) extracts exhibit anti-inflammatory, anti-cancer, and antibacterial properties. This study was designed to investigate the antibacterial impact of AR extract on Streptococcus mutans (S. mutans) UA159 and the anti-caries effect on rats.

METHODS

The antibacterial activity of AR extract against S. mutans and its biofilm was determined using the bacterial sensitivity test, the biofilm sensitivity test, and the live-dead staining technique. By fluorescently tagging bacteria, the influence of bacterial adhesion rate was determined. Using a rat caries model, the anti-caries efficacy and safety of AR extract were exhaustively investigated in vivo.

RESULTS

AR extract inhibit not only the growth of S. mutans, but also the generation of S. mutans biofilm, hence destroying and eliminating the biofilm. Moreover, AR extract were able to inhibit S. mutans' adherence to saliva-encapsulated hydroxyapatite (HAP). Further, in a rat model of caries, the AR extract is able to greatly reduce the incidence and severity of caries lesions on the smooth surface and pit and fissure of rat molars, while exhibiting excellent biosafety.

CONCLUSIONS

AR extract exhibit strong antibacterial activity against S. mutans and can lower the incidence and severity of dental cavities in rats. These findings suggest that Arnebia euchroma (Royle) Johnst. could be utilized for the prevention and treatment of dental caries.

Cell Membrane Sialome: Sialic Acids as Therapeutic Targets and Regulators of Drug Resistance in Human Cancer Management

A cellular sialome is a physiologically active and dynamically changing component of the cell membrane. Sialylation plays a crucial role in tumor progression, and alterations in cellular sialylation patterns have been described as modulators of chemotherapy effectiveness. However, the precise mechanisms through which altered sialylation contributes to drug resistance in cancer are not yet fully understood. This review focuses on the intricate interplay between sialylation and cancer treatment. It presents the role of sialic acids in modulating cell-cell interactions, the extracellular matrix (ECM), and the immunosuppressive processes within the context of cancer. The issue of drug resistance is also discussed, and the mechanisms that involve transporters, the tumor microenvironment, and metabolism are analyzed. The review explores drugs and therapeutic approaches that may induce modifications in sialylation processes with a primary focus on their impact on sialyltransferases or sialidases. Despite advancements in cellular glycobiology and glycoengineering, an interdisciplinary effort is required to decipher and comprehend the biological characteristics and consequences of altered sialylation. Additionally, understanding the modulatory role of sialoglycans in drug sensitivity is crucial to applying this knowledge in clinical practice for the benefit of cancer patients.