Endocannabinoid signalling/cannabinoid receptor 2 is involved in icariin-mediated protective effects against bleomycin-induced pulmonary fibrosis

Efficacy and Mechanisms of Natural Products as Therapeutic Interventions for Chronic Respiratory Diseases

Chronic respiratory diseases are long-term conditions affecting the airways and other lung components that are characterized by a high prevalence, disability rate, and mortality rate. Further optimization of their treatment is required. Natural products, primarily extracted from organisms, possess specific molecular and structural formulas as well as distinct chemical and physical properties. These characteristics grant them the advantages of safety, gentleness, accessibility, and minimal side effects. The numerous advances in the use of natural products for treating chronic respiratory diseases have provided a steady source of motivation for new drug research and development. In this paper, we introduced the pathogenesis of chronic respiratory diseases and natural products. Furthermore, we classified natural products according to their mechanism for treating chronic respiratory diseases and describe the ways in which these products can alleviate the pathological symptoms. Simultaneously, we elaborate on the signal transduction pathways and biological impacts of natural products' targeting. Additionally, we present future prospects for natural products, considering their combination treatment approaches and administration methods. The significance of this review extends to both the research on preventing and treating chronic respiratory diseases, as well as the advancement of novel drug development in this field.

Exploring the therapeutic potential of natural compounds modulating the endocannabinoid system in various diseases and disorders: review

Cannabinoid receptors, endogenous cannabinoids (endocannabinoids), and the enzymes involved in the biosynthesis and degradation of the endocannabinoids make up the endocannabinoid system (ECS). The components of the ECS are proven to modulate a vast bulk of various physiological and pathological processes due to their abundance throughout the human body. Such discoveries have attracted the researchers' attention and emerged as a potential therapeutical target for the treatment of various diseases. In the present article, we reviewed the discoveries of natural compounds, herbs, herbs formula, and their therapeutic properties in various diseases and disorders by modulating the ECS. We also summarize the molecular mechanisms through which these compounds elicit their properties by interacting with the ECS based on the existing findings. Our study provides the insight into the use of natural compounds that modulate ECS in various diseases and disorders, which in turn may facilitate future studies exploiting natural lead compounds as novel frameworks for designing more effective and safer therapeutics.

DNA-templated copper nanocluster: A robust and universal fluorescence switch for bleomycin assay

Bleomycin (BLM) is widely utilized for cancer treatment due to the outstanding antitumor activity, but BLM with imprecisely controlled dosage may lead to lethal consequences. It is thus a profound task to accurately monitor the BLM levels in clinical settings. Herein, we propose a straightforward, convenient, and sensitive sensing method for BLM assay. Poly-T DNA-templated copper nanoclusters (CuNCs) are fabricated with strong fluorescence emission and uniform size distribution and served as fluorescence indicators for BLM. The high binding affinity of BLM for Cu²⁺makes it able to inhibit fluorescence signals generated from CuNCs. This is the underlying mechanism rarely explored and can be utilized for effective BLM detection. A detection limit of 0.27 μM (according to 3σ/s rule) is achieved in this work. And the precision, producibility, and practical useability are also confirmed with satisfactory results. Furthermore, the accuracy of the method is verified by high-performance liquid chromatography (HPLC). To sum up, the established strategy in this work exhibits the advantages of convenience, rapidness, low cost, and high precision. The construction of BLM biosensors is important to achieve the best therapeutic effect with minimal toxicity, which opens a new avenue for monitoring antitumor drugs in clinical settings.

Discovery of a pyrano[2,3-b]pyridine derivative YX-2102 as a cannabinoid receptor 2 agonist for alleviating lung fibrosis

BACKGROUND

Pharmacological modulation of cannabinoid 2 receptor (CB2R) is a promising therapeutic strategy for pulmonary fibrosis (PF). Thus, to develop CB2R selective ligands with new chemical space has attracted much research interests. This work aims to discover a novel CB2R agonist from an in-house library, and to evaluate its therapeutic effects on PF model, as well as to disclose the pharmacological mechanism.

METHODS

Virtual screening was used to identify the candidate ligand for CB2R from a newly established in-house library. Both in vivo experiments on PF rat model and in vitro experiments on cells were performed to investigate the therapeutic effects of the lead compound and underlying mechanism.

RESULTS

A "natural product-like" pyrano[2,3-b]pyridine derivative, YX-2102 was identified that bound to CB2R with high affinity. Intraperitoneal YX-2102 injections significantly ameliorated lung injury, inflammation and fibrosis in a rat model of PF induced by bleomycin (BLM). On one hand, YX-2102 inhibited inflammatory response at least partially through modulating macrophages polarization thereby exerting protective effects. Whereas, on the other hand, YX-2102 significantly upregulated CB2R expression in alveolar epithelial cells in vivo. Its pretreatment inhibited lung alveolar epithelial-to-mesenchymal transition (EMT) in vitro and PF model induced by transforming growth factor beta-1 (TGF-β1) via a CB2 receptor-dependent pathway. Further studies suggested that the Nrf2-Smad7 pathway might be involved in.

CONCLUSION

These findings suggest that CB2R is a potential target for PF treatment and YX-2102 is a promising CB2R agonist with new chemical space.

Oleamide Reduces Mitochondrial Dysfunction and Toxicity in Rat Cortical Slices Through the Combined Action of Cannabinoid Receptors Activation and Induction of Antioxidant Activity

The potential treatment of neurodegenerative disorders requires the development of novel pharmacological strategies at the experimental level, such as the endocannabinoid-based therapies. The effects of oleamide (OEA), a fatty acid primary amide with activity on cannabinoid receptors, was tested against mitochondrial toxicity induced by the electron transport chain complex II inhibitor, 3-nitropropionic acid (3-NP), in rat cortical slices. OEA prevented the 3-NP-induced loss of mitochondrial function/cell viability at a concentration range of 5 nM-25 µM, and this protective effect was observed only when the amide was administered as pretreatment, but not as post-treatment. The preservation of mitochondrial function/cell viability induced by OEA in the toxic model induced by 3-NP was lost when the slices were pre-incubated with the cannabinoid receptor 1 (CB1R) selective inhibitor, AM281, or the cannabinoid receptor 2 (CB2R) selective inhibitor, JTE-907. The 3-NP-induced inhibition of succinate dehydrogenase (mitochondrial Complex II) activity was recovered by 25 nM OEA. The amide also prevented the increased lipid peroxidation and the changes in reduced/oxidized glutathione (GSH/GSSG) ratio induced by 3-NP. The cell damage induced by 3-NP, assessed as incorporation of cellular propidium iodide, was mitigated by OEA. Our novel findings suggest that the neuroprotective properties displayed by OEA during the early stages of damage to cortical cells involve the converging activation of CB1R and CB2R and the increase in antioxidant activity, which combined may emerge from the preservation of the functional integrity of mitochondria.