Repairing Effect and Mechanism of Hydroxysafflor Yellow A and Sodium Hyaluronate for Knee Osteoarthritis in Rabbits.

Context: KOA characterized by recurrent joint pain and progressive joint dysfunction. Is the present clinical common chronic progressive degenerative osteoarthropathy, how long the disease is difficult to cure and easy to relapse. Exploring new therapeutic approaches and mechanisms is important for the treatment of KOA. One of the main applications for sodium hyaluronate (SH) in the medical field is treatment of osteoarthritis. However, the effects of SH alone in the treatment of KOA are limited. Hydroxysafflor yellow A (HSYA) may have therapeutic effects for KOA. Objective: The study intended to investigate the therapeutic effects and possible mechanisms of action HSYA+SH for cartilage tissue of rabbits with KOA and to provide a theoretical basis for the treatment of KOA. Design: The research team performed an animal study. Setting: The study that took place at Liaoning Jijia Biotechnology, Shenyang, Liaoning, China. Animals: The animals were 30 healthy, adult, New Zealand white rabbits, weighing 2-3 kg. Intervention: The research team randomly divided the rabbits into three groups, with 10 rabbits in each group: (1) a control group, for which the research team didn't induce KOA and provided no treatment; (2) the HSYA+SH group, the intervention group, for which the research team induced KOA and injected the rabbits with the HSYA+SH treatment; and (3) the KOA group, for which the research team induced KOA and injected the rabbits with saline. Outcome Measures: The research team: (1) observed the morphological changes in the cartilage tissue using hematoxylin-eosin (HE) staining; (2) measured levels of serum inflammatory factors, including tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1ß), interferon gamma (IFN-γ), IL-6, and IL-17 using an enzyme-linked immunosorbent assay (ELISA); (3) measured cartilage-cell apoptosis using "terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling" (TUNEL); and (4) used Western Blot to detect the expression of proteins related to the "neurogenic locus notch homolog protein 1" (Notch1) signaling pathway. Results: Compared with the control group, morphological changes had occurred to the cartilage tissue in the KOA group. Compared with the control group, that group's level of apoptosis was higher, the levels of serum inflammatory factors were significantly higher (P < .05), and the protein expression related to the Notch1 signaling pathway was also significantly higher (P < .05). The morphology of the cartilage tissue in the HSYA+SH was better than that of the KOA group but not as good as that of the control group. Compared with the KOA group, the HSYA+SH group's level of apoptosis was lower, the levels of serum inflammatory factors were significantly lower (P < .05), and the protein expression related to the Notch1 signaling pathway was also significantly lower (P < .05). Conclusions: HSYA+SH can reduce the cellular apoptosis in the cartilage tissue of rabbits with KOA, downregulate the levels of inflammatory factors, and protect against KOA-induced cartilage tissue injury, and the mechanism may be related to the regulation of the Notch1 signaling pathway.

Development of a novel nitric oxide (NO) production inhibitor with potential therapeutic effect on chronic inflammation.

Inflammation is a complex biological response to stimuli. Activated macrophages induced excessively release of pro-inflammatory cytokines and mediators such as endogenous radical nitric oxide (NO) play a significant role in the progression of multiple inflammatory diseases. Both natural and synthetic chalcones possess a wide range of bioactivities. In this work, thirty-nine chalcones and three related compounds, including several novel ones, based on bioactive kava chalcones were designed, synthesized and their inhibitory effects on NO production in RAW 264.7 cells were evaluated. The novel compound (E)-1-(2'-hydroxy-4',6'-dimethoxyphenyl)-3-(3-methoxy-4-(3-morpholinopropoxy)phenyl)prop-2-en-1-one (53) exhibited a better inhibitory activity (84.0%) on NO production at 10 µM (IC50 = 6.4 µM) with the lowest cytotoxicity (IC50 > 80 µM) among the tested compounds. Besides, western blot analysis indicated that compound 53 was a potent down-regulator of inducible nitric oxide synthase (iNOS) protein. Docking study revealed that compound 53 also can dock into the active site of iNOS. Furthermore, at the dose of 10 mg/kg/day, compound 53 could both significantly suppress the progression of inflammation on collagen-induced arthritis (CIA) and adjuvant-induced arthritis (AIA) models. In addition, the structure-activity relationship (SAR) of the kava chalcones based analogs was also depicted.

Synthesis and biological evaluation of pyranoisoflavone derivatives as anti-inflammatory agents.

In this paper, barbigerone (1a) and its twenty-seven related structural analogues were synthesized via complementary synthetic routes and their anti-inflammatory effects on the expression of TNF-α in LPS-stimulated splenocytes were evaluated. Among these compounds, 1a, 1d, 1f and 1g were found to remarkably inhibit TNF-α production. Furthermore, 1g showed the most potent and dose-dependent manner inhibitory effect on TNF-α release, with better IC50 value (3.58 µM) than barbigerone (8.46 µM). Oral administration of 1g at 20 mg/kg/day for two weeks obviously demonstrated protective effect in adjuvant-induced arthritis models as evaluated by clinical score of paws, and histological examination of joint tissues from rats. Mechanism studies on mRNA and protein level suggested that 1g inhibited the TNF-α production via depressing TNF-α converting enzyme (TACE) mRNA expression. In conclusion, these data show 1g with potential therapeutic effects as an anti-inflammatory agent.