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Vascular dementia (VaD) is a neurodegenerative disease resulting from cerebral vascular obstruction, leading to cognitive impairment, and currently lacks effective treatment options. Due to its complex pathogenesis, multi-target drug design (MTDLs) strategies are considered among the most promising therapeutic approaches. In this study, we designed and synthesized a series of novel indanone derivatives targeting targets related to vascular health and dementia. The results indicated that compound C5 exhibited excellent acetylcholinesterase inhibitory activity (IC50 = 1.16 ± 0.41 μM) and anti-platelet aggregation activity (IC50 = 4.92 ± 0.10 μM) within ranges of 0.1-1000 μM and 0.03-300 μM, respectively, possibly mediated by molecular docking interactions. Furthermore, compound C5 demonstrated protective effects on cells at concentrations ≤50 μM, significantly reducing the release of nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1β) in a concentration-dependent manner, showcasing its potent neuroinflammatory inhibitory effects. Anti-inflammatory therapies are regarded as effective strategies for treating VaD. Therefore, compound C5 holds promise as a novel candidate drug for further investigation into the treatment of vascular dementia., (© 2024 Wiley‐VCH GmbH.)

Polycyclic tetramate macrolactams (PTMs) are a widely distributed class of structurally complex natural products, and most of them exhibit multiple biological activities. However, the transcriptional regulators (TRs) involved in the regulation of PTM production have seldom been reported. Here, we identified three TRs, i.e., Sxim_22880, CvnABC Sx , and WblA Sx , and revealed their positive roles in the regulation of PTM biosynthesis in mangrove-derived Streptomyces xiamenensis 318. This strain produces a considerable amount of PTMs at 30 °C, but the production of PTMs is mostly blocked at 37 °C. Quantitative real-time PCR analysis confirmed that the transcriptions of PTM biosynthetic genes were downregulated. We determined that the transcriptions of several putative TRs, i.e., WblA Sx , Sxim_22880, and CvnC Sx , were significantly downregulated under such heat-shock conditions. We showed that the transcription of PTM biosynthetic genes and the production of PTMs could be restored at 37 °C if the impaired transcriptions of wblA Sx , sxim_22880, and cvnABC Sx were restored. Electrophoretic mobility shift assays showed that none of these TRs could bind to the promoter region of the PTM gene cluster, suggesting their indirect but positive involvement in the regulation on PTM production. Moreover, concurrent overexpression of the three TRs in S. xiamenensis 318 resulted in a 242.5% increase in PTM production when the strain was cultured at 30 °C. Furthermore, overexpression of these three TRs in Streptomyces sp. FR-008 and S. albus J1074 stimulated the production of new secondary metabolites, indicating that these conserved TRs could be used to activate cryptic secondary metabolite gene clusters in Streptomyces.