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In traditional Chinese medicine, propolis has been used for treating oral diseases for centuries, widely. Flavonoid extract is the main active ingredient in propolis, which has attracted extensive attention in recent years. The objective and novelty of the current study aims to identify the mechanism of total flavonoid extract of propolis (TFP) for the treatment of periodontitis, and evaluate the therapeutic effect of TFP-loaded liquid crystal hydrogel (TFP-LLC) in rats with periodontitis. In this study, we used lipopolysaccharide-stimulated periodontal ligament stem cells (PDLSCs) to construct in vitro inflammation model, and investigated the anti-inflammatory effect of TFP by expression levels of inflammatory factors. Osteogenic differentiation was assessed using alkaline phosphatase activity and alizarin red staining. Meanwhile, the expression of toll like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), nuclear factor-kappa B (NF- κ B), receptor activator of NF- κ B (RANK) etc, were quantitated to investigate the therapeutic mechanism of TFP. Finally, we constructed TFP-LLC using a self-emulsification method and administered it to rats with periodontitis via periodontal pocket injection to evaluate the therapeutic effects. The therapeutic index, microcomputed tomography (Micro-CT), H&E staining, TRAP staining, and Masson staining were used for this evaluation. TFP reduced the expression of TLR4, MyD88, NF- κ B and inflammatory factor in lipopolysaccharide-stimulated PDLSCs. Meanwhile, TFP simultaneously regulating alkaline phosphatase, RANK, runt-associated transcription factor-2 and matrix metalloproteinase production to accelerate osteogenic differentiation and collagen secretion. In addition, TFP-LLC can stably anchor to the periodontal lesion site and sustainably release TFP. After four weeks of treatment with TFP-LLC, we observed a decrease in the levels of NF- κ B and interleukin-1 β (IL-1β) in the periodontal tissues of rats, as well as a significant reduction in inflammation in HE staining. Similarly, Micro CT results showed that TFP-LLC could significantly inhibit alveolar bone resorption, increase bone mineral density (BMD) and reduce trabecular bone space (Tb.Sp) in rats with periodontitis. Collectively, we have firstly verified the therapeutic effects and mechanisms of TFP in PDLSCs for periodontitis treatment. Our results indicate that TFP perform anti-inflammatory and tissue repair activities through TLR4/MyD88/NF-κB and RANK/NF- κ B pathways in PDLSCs. Meanwhile, for the first time, we employed LLC delivery system to load TFP for periodontitis treatment. The results showed that TFP-LLC could be effectively retained in the periodontal pocket and exerted a crucial role in inflammation resolution and periodontal tissue regeneration. Scheme 1. Schematic diagram of TFP-LLC alleviating periodontitis via PDLSCs-dependent anti-inflammatory and periodontium regeneration mechanism. TFP–LLC was in situ injected into the periodontal pocket to ensure the sustained release of the active TFP ingredients at the periodontal lesion. TFP–LLC suppresses the expression of inflammatory factors and osteoclastogenesis by interfering with TLR4/MyD88/NF-κB and RANK/NF-κB signaling. In addition, TFP–LLC promotes osteogenic differentiation and collagen regeneration in PDLSCs, as demonstrated by the upregulation of ALP and RUNX2 and downregulation of MMP. The TFP–LLC-induced periodontal homeostasis alleviates acute periodontal inflammation and assists in the long-term tissue regeneration of the gingiva, cementum, periodontal ligament, and alveolar bone, thereby demonstrating comprehensive treatment efficacy in periodontitis. [Display omitted] • We demonstrated that TFP exerts an anti-inflammatory pathway through TLR4/MyD88/NF-κB pathway in PDLSCs. • We proved TFP boosting periodontium regeneration via RANK/NF- κ B pathway in PDLSCs. • We prepared lyotropic liquid crystals containing total flavonoid extract of propolis (TFP-LLC). • TFP-LLC was stably anchored to the periodontal lesion site to form a drug reservoir. • TFP-LLC demonstrated excellent periodontal protection in rats with periodontitis. [ABSTRACT FROM AUTHOR]

Zhizhu Xiang (ZZX for short) is the root and rhizome of Valeriana jatamansi Jones, which is a Traditional Chinese Medicine (TCM) used to treat various mood disorders for more than 2000 years, especially anxiety. However, there have been few investigations to clarify the compounds in ZZX for the treatment of anxiety. Our previous study has identified five anti-anxiety components, including hesperidin, isochlorogenic acid A, isochlorogenic acid B and isochlorogenic acid C and chlorogenic acid, from extract of ZZX. In order to find the optimal combination and the underlying mechanism of these five components in the treatment of anxiety disorder, researches were designed based on uniform design method and proteomic technology. The samples with different proportion and content of the five active components were arranged by uniform design method. Then a mathematical model was formulated using partial least square method and stepwise regression analysis. Moreover, the empty bottle stress-induced anxiety rat model was established, and the anti-anxiety effect was recorded by the unconditioned reflex elevated maze test and the open field test. In addition, the isobaric tags for relative and absolute quantitation (iTRAQ) technique, along with the multidimensional liquid chromatography and high-resolution mass spectrometry were applied in proteomic study. At last, the result of proteomic analysis was further confirmed by Western blot. The optimal combination of the components from the extract of ZZX was 1.153 mg/kg hesperidin, 2.197 mg/kg Isochlorogenic acid A, 0.699 mg/kg Isochlorogenic acid B and 1.249 mg/kg Chlorogenic acid. Total 6818 proteins were identified using proteomic analysis and 80 differentially expressed proteins were used for further bioinformatic analysis. These proteins were involved in the neuroactive ligand-receptor interaction, protein digestion and absorption, cholesterol metabolism, Chagas disease, and AGE/RAGE signaling pathway. The composition and proportion of anti-anxiety components in extract of ZZX was disclosed, and there was an anti-anxiety effect for the combined components of flavonoids and phenolic acids. Through proteomic analysis and Western blot, it was found that the effective components of extract of ZZX can exert synergistic anti-anxiety effects via the regulation of multi-signaling pathways. These findings could provide a preliminary research basis for the development of new low-toxic, efficient, stable and controllable anti-anxiety drugs. Image 1 • The optimal combination of the antianxiety components in ZZX (the root and rhizome of Valeriana jatamansi Jones) was 1.153 mg/kg hesperidin, 2.197 mg/kg Isochlorogenic acid A, 0.699 mg/kg Isochlorogenic acid B and 1.249 mg/kg Chlorogenic acid. • During the proteomic analysis, 80 proteins in rats were significantly influenced after dosing components mentioned above. • Bioinformatic analyze results showed that the mechanism of ZZX-OS protect EBS rats from anxiety is related with the neuroactive ligand-receptor interaction, protein digestion and absorption, cholesterol metabolism, Chagas disease, and AGE/RAGE signaling pathway. [ABSTRACT FROM AUTHOR]