Discovery of diarylheptanoids that activate α7 nAchR-JAK2-STAT3 signaling in macrophages with anti-inflammatory activity in vitro and in vivo

DANCR knockdown alleviates neuroinflammation and functional recovery after spinal cord injury via regulating the ACTN4 / STAT3 axis

Polarization of microglia following spinal cord injury (SCI) is a pivotal pathological process of secondary injury. Although differentiation antagonistic nonprotein coding RNA (DANCR) has been implicated in immune and inflammatory responses across various diseases, its role in SCI still unclear. This research aimed to clarify the underlying mechanisms of DANCR in SCI recovery by investigating its expression pattern in microglia. Our findings indicate that the DANCR level in microglia is increased after SCI and that its knockdown can promote microglial M2-type polarization; suppress inflammatory cytokines, oxidative stress, and neuronal apoptosis; and facilitate nerve regeneration as well as spinal cord functional recovery. Further investigations suggest that DANCR's effects are mediated through the ACTN4/STAT3 axis. These results provide potential targets for enhancing functional recovery following SCI.

Discovery of novel capsaicin analogs as TRPV1 inhibitors for the treatment of idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal interstitial lung disease for which few drugs are available in clinical practice. Here, we identified novel capsaicin analogs by combining in-house chemical library screening and further structural optimization. (E)-1-(3,4-dihydroxyphenyl)-7-phenylhept-1-en-3-one (Compound 14) was found to be the most potent in inhibiting TGF-β-induced collagen accumulation, proliferation and migration in fibroblast cells. Furthermore, compound 14 (IC50 = 0.51 ± 0.06 μM) showed over 100-fold increasing antifibrotic activity compared to capsaicin (IC50 = 53.71 ± 4.78 μM). Notably, compound 14 could target TRPV1, thereby affecting the expression of the fibrosis markers Collagen Ⅰ and α-SMA by inhibiting the TGF-β/Smads and MAPK pathways to exert antifibrotic activity in vitro. Compound 14 significantly inhibited collagen deposition in lung tissues, ameliorated alveolar structures, and increased survival rates in mice with bleomycin-induced pulmonary fibrosis. In addition, compound 14 possessed lower cytotoxicity (compared to nitedanib) and no toxicity in mice. Overall, compound 14 promise as a potential drug candidate for the treatment of IPF.

Total Synthesis and Anti-Inflammatory Activity of Tectoridin and Related Isoflavone Glucosides

The first total syntheses of four isoflavone glucosides, tectoridin (1), tectoridin A (2), tectorigenin 7-O-β-d-glucopyranosyl-12-O-β-d-glucopyranoside (3), and isotectroigenin 7-O-β-d-glucopyranoside (4), have been accomplished. Key steps in our synthetic approach include a regioselective halogenation reaction, followed by methanolysis to introduce the -OCH3 group into isoflavone frameworks and a PTC-promoted stereoselective glycosidation to establish glycosidic bonds. The synthesized isoflavone glucosides (1-4) and their corresponding aglycones (32 and 34) were evaluated for anti-inflammatory activity against nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1 β (IL-1β) in lipopolysaccharide (LPS)-induced RAW264.7 cells. Aglycones 32 and 34 exhibited stronger anti-inflammatory activity in vitro compared to isoflavone glucosides 1-4.

The Role of Alpha-7 Nicotinic Acetylcholine Receptors in Pain: Potential Therapeutic Implications

Chronic pain represents a prevalent and costly medical challenge globally. Nicotinic acetylcholine receptors (nAChRs), one type of ligand-gated ion channels found extensively in both the central and peripheral nervous systems, have emerged as promising therapeutic targets for chronic pain. Although there are currently no FDA-approved analgesics specifically targeting nAChRs, accumulating preclinical and clinical evidence suggest that selective ligands for alpha 7 (α7) nAChRs show potential for treating chronic pain, boasting a reduced incidence of side effects compared with other nicotinic receptor types. The recent structural resolution of human α7 nAChRs has confirmed their negative association with heightened pain, providing a valuable foundation for the development of targeted medications. This review presents a comprehensive overview, encompassing insights into the roles of α7 nAChRs derived from structural and functional studies, recent advancements in pharmacology, and investigations into their involvement in the pathophysiology of chronic pain. Moreover, the review addresses the variability in analgesic effects based on the type of receptor agonist and highlights the current research limitations. As such, this review offers potential therapeutic approaches for the development of innovative strategies for chronic pain management.

Molecular mechanisms of Sepsis attacking the immune system and solid organs

Remarkable progress has been achieved in sepsis treatment in recent times, the mortality rate of sepsis has experienced a gradual decline as a result of the prompt administration of antibiotics, fluid resuscitation, and the implementation of various therapies aimed at supporting multiple organ functions. However, there is still significant mortality and room for improvement. The mortality rate for septic patients, 22.5%, is still unacceptably high, accounting for 19.7% of all global deaths. Therefore, it is crucial to thoroughly comprehend the pathogenesis of sepsis in order to enhance clinical diagnosis and treatment methods. Here, we summarized classic mechanisms of sepsis progression, activation of signal pathways, mitochondrial quality control, imbalance of pro-and anti- inflammation response, diseminated intravascular coagulation (DIC), cell death, presented the latest research findings for each mechanism and identify potential therapeutic targets within each mechanism.

Recent Advances in the Synthesis of Diarylheptanoids

In the quest for synthesizing biologically important natural products, medicinal chemists embark on an endless journey. This review focuses on the reports published towards the syntheses of diarylheptanoids, classifying them into linear, tetrahydropyran, diarylether, and biphenyl categories. The synthesis methods for each class from 2013 to 2023 are discussed, providing a comprehensive overview of the advancements in the field. Representative natural product examples are highlighted for each category. The review emphasizes the importance of diarylheptanoids in the realms of chemistry and medicine, showcasing their potential as valuable compounds for medicinal and synthetic chemists.

Marine sponge-derived alkaloid ameliorates DSS-induced IBD via inhibiting IL-6 expression through modulating JAK2-STAT3-SOCS3 pathway

Cyanogramide (AC14), a novel alkaloid, isolated from the fermentation broth of the marine-derived Actinoalloteichus cyanogriseus. However, the exact role of AC14 in inflammatory bowel disease (IBD) is poorly understood. Our results demonstrated that AC14 exhibited significant inhibition of IL-6 release in THP-1 cells and a "Caco-2/THP-1" coculture system after stimulation with LPS for 24 h. However, no significant effect on TNF-α production was observed. Furthermore, in 2.5 % DSS-induced colitis mice, AC14 treatment led to improvement in body weight, colon length, and intestine mucosal barrier integrity. AC14 also suppressed serum IL-6 production and modulated dysregulated microbiota in the mice. Mechanistically, AC14 was found to inhibit the phosphorylation of Janus kinase (JAK) 2 and signal transducers and activators of transcription (STAT) 3, while simultaneously elevating the expression of suppressor of cytokine signaling (SOCS) 3, both in vivo and in vitro. These findings suggest that AC14 exerts its suppressive effects on IL-6 production in DSS-induced IBD mice through the JAK2-STAT3-SOCS3 signaling pathway. Our study highlights the potential of AC14 as a therapeutic agent for the treatment of IBD.

Transcriptome analysis revealed the function of five tandemly duplicated nAChRs in the transplantation immunity in pearl oyster Pinctada fucata martensii

nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels that play an important role in the homeostatic regulation of physiological functions. Our previous studies showed that nAChRs in the genome of pearl oyster Pinctada fucata martensii (PmnAChRs) were expanded through tandem duplication. This study aimed to analyze the function of five tandemly duplicated PmnAChRs in the transplantation immunity in P. f. martensii. Transcriptome analysis reveals that the differentially expressed genes (DEGs) shared between PmnAChR-RNAi and the control group were functionally involved in Signal transduction, Immune system et al., and most of the related genes were down-regulated in the PmnAChR-RNAi group. The different copies of PmnAChR may regulate transplantation immunity through various pathways, such as Wnt, protein digestion and absorption, Hippo, and gap junction pathway. The inflammation factor interleukin-17 (IL-17) and tumor necrosis factor-alpha (TNF-α) were down-regulated in PmnAChR-1, 4, 5-RNAi group, and the serum from the pearl oysters in the PmnAChR-1-4-RNAi group could promote the proliferation of the Vibrio harveyi, indicating the immunosuppressive function after down-regulation of PmnAChRs. The different responses of antioxidant enzymes and diverse signal pathways after down-regulation of PmnAChRs suggested that the five tandemly duplicated PmnAChRs may cooperate with different α type PmnAChRs and constitute the functional ion channel in the membrane. Results of this study not only provide insight for the effective regulation of the transplantation immunity, but also provide a theoretical reference for the study of the adaptive evolutionary mechanism of repeating genes.