Natural compound library screening to identify berberine as a treatment for rheumatoid arthritis.

OBJECTIVE: Fibroblast-like synoviocytes (FLS) play a critical role on the exacerbation and deterioration of rheumatoid arthritis (RA). Aberrant activation of FLS pyroptosis signaling is responsible for the hyperplasia of synovium and destruction of cartilage of RA. This study investigated the screened traditional Chinese medicine berberine (BBR), an active alkaloid extracted from the Coptis chinensis plant, that regulates the pyroptosis of FLS and secretion of inflammatory factors in rheumatoid arthritis. METHODS: First, BBR was screened using a high-throughput drug screening strategy, and its inhibitory effect on RA-FLS was verified by in vivo and in vitro experiments. Second, BBR was intraperitoneally administrated into the collagen-induced arthritis rat model, and the clinical scores, arthritis index, and joint HE staining were evaluated. Third, synovial tissues of CIA mice were collected, and the expression of NLRP3, cleaved-caspase-1, GSDMD-N, Mst1, and YAP was detected by Western blot. RESULTS: The administration of BBR dramatically alleviated the severity of collagen-induced arthritis rat model with a decreased clinical score and inflammation reduction. In addition, BBR intervention significantly attenuates several pro-inflammatory cytokines (interleukin-1ß, interleukin-6, interleukin-17, and interleukin-18). Moreover, BBR can reduce the pyroptosis response (caspase-1, NLR family pyrin domain containing 3, and gasdermin D) of the RA-FLS in vitro, activating the Hippo signaling pathway (Mammalian sterile 20-like kinase 1, yes-associated protein, and transcriptional enhanced associate domains) so as to inhibit the pro-inflammatory effect of RA-FLS. CONCLUSION: These results support the role of BBR in RA and may have therapeutic implications by directly repressing the activation, migration of RA-FLS, which contributing to the attenuation of the progress of CIA. Therefore, targeting PU.1 might be a potential therapeutic approach for RA. Besides, BBR inhibited RA-FLS pyroptosis by downregulating of NLRP3 inflammasomes (NLRP3, caspase-1) and eased the pro-inflammatory activities via activating the Hippo signaling pathway, thereby improving the symptom of CIA.

Huoxue Jiedu Recipe represses mitochondrial fission to alleviate submandibular gland inflammation in Sjögren's syndrome.

Sjögren's syndrome (SS) is the second most common autoimmune rheumatism. Huoxue Jiedu Recipe (HXJDR) is a kind of traditional Chinese medicine with a variety of pharmacological functions; however, its biological function in SS has not been studied yet. Peripheral blood mononuclear cells (PBMCs) and serum samples were isolated from healthy controls and patients with SS. NOD/Ltj mice were used for developing the SS mouse model. The levels of inflammatory cytokines and NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-related markers as well as dynamin-related protein 1 (Drp1) were determined by ELISA, quantitative real-time PCR, and western blot analysis, respectively. Hematoxylin and eosin and TUNEL staining detected the pathological damage. A transmission electron microscope was used to observe the mitochondrial microstructure. Inflammatory cytokines IL-18, IL-1ß, B-cell activating factor (BAFF), BAFF-receptor (BAFF-R), IL-6, and TNF-α in serum samples and NLRP3 inflammasome-related makers (NLRP3, cysteinyl aspartate-specific proteinase 1 [caspase-1], apoptosis-associated speck-like protein containing a caspase-1 recruitment domain [ASC], IL-1ß) in PBMCs were greatly upregulated in patients with SS. Furthermore, cytoplasmic phosphorylation of Drp1 and mitochondrial Drp1 level were significantly increased in PBMCs, while mitochondrial swelling and fuzzy inner ridge were observed in PBMCs of patients with SS, suggesting increased mitochondrial fission. Compared with control mice, SS mice showed decreased salivary flow rate, increased submandibular gland index, and more severe inflammatory infiltration and damage as well as mitochondrial fission in submandibular gland tissues. After HXJDR administration, these effects were significantly reversed. HXJDR treatment could alleviate the inflammatory infiltration and pathological damage in submandibular glands of SS mice by inhibiting Drp-1-dependent mitochondrial fission.

ß-caryophyllene oxide induces apoptosis and inhibits proliferation of A549 lung cancer cells.

One of the most common cancers that result in death is lung cancer. There is new hope in the fight against lung cancer thanks to the chemopreventive properties of natural dietary substances like ß-caryophyllene oxide (CPO), and research is currently being done to test this theory. CPO, a sesquiterpene isolated from medicinal plant essential oils, inhibits carcinogenesis and has been effective in treating many cancers. This study examined how CPO affected proliferation of human lung cancer A549 cells. CPO was found to have an inhibitory concentration (IC50) of 124.1 g/ml. The proliferative markers Ki67 and PCNA were significantly inhibited after cells were treated with CPO at a concentration of 50 g/ml compared to controls. CPO-treated cells expressed more P21, P53, and DNA strand breaks than controls. This was accompanied by a significant cell cycle arrest in the S and G2/M phases. In treated A549 cells, this was also associated with a significant induction of apoptosis, as shown by the upregulation of the expression of caspases 3, 7, and 9, as well as Bax, and the downregulation of Bcl-2. Furthermore, the redox status of treated A549 cells revealed a marked rise in GSH and GPx activity levels and a decline in 4-HNE levels, indicating low oxidative stress following CPO treatment of A549 cells. In conclusion, cell cycle arrest and apoptosis, which are unrelated to oxidative stress, were the mechanisms by which CPO reduced cancer lung cell growth. This finding might be a potential therapeutic target for the treatment of lung cancer. Hypothetical scheme of CPO anticancer effects (mechanism of signaling) in A549 cells; in vitro. CPO treatment increases expression of p21, p53 and DNA fragmentation. These events cause arrest of cell cycle which was associated with significant induction in apoptosis via increase expression of caspases (-3,-7,-9), and Bax and downregulation of Bcl-2.

[Effect of electroacupuncture on pyroptosis of synovial tissues in rats with knee osteoarthritis].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on pyroptosis-related proteins in synovium of knee joint in rats with knee osteoarthritis(KOA), in order to explore its mechanism underlying improvement of KOA. METHODS: Forty male SD rats were randomly divided into control， model, EA and medication groups, with 10 rats in each group. The KOA model was established by injecting 0.2 mL 4% papain solution into the right intra-articular cavity, followed by repeating the injection again on day 4 and 7 after the first injection. After successful modeling, rats of the EA group received EA stimulation of "Neixiyan" (EX-LE4) and "Dubi"(ST35) on the right limb for 15 min, once every day, 6 days per week, for a total of 4 weeks, and those of the medication group received gavage of celecoxib 24 mg/kg, once every day, 6 days per week, for a total of 4 weeks. The severity of dysfunction of the right knee was assessed by using Lequesne's score. Serum interleukin(IL)-1ß and IL-18 contents were detected by ELISA. Histopathological changes of the synovium tissue of the right knee joint were observed to give score (synovial pathological score) after H.E. staining. The expression position and intensity of Nod-like receptor pyrin domain 3 (NLRP3) in syno-vial tissue were observed by immunohistochemistry. The expression levels of NLRP3, apoptosis-associated speck-like protein containing card (ASC), Caspase-1, Gasdermin D(GSDMD), IL-1ß and IL-18 mRNAs and proteins (including GSDMD-N) in the synovial tissue of the right knee joint were detected by real-time fluorescence quantitative PCR and Western blot, separately. RESULTS: Compared with the control group, the model group had a significant increase in the Lequesne's score, synovial pathological score, serum IL-1ß and IL-18 contents, and the expression levels of NLRP3, ASC, Caspase-1, GSDMD, IL-1ß, IL-18 mRNAs and proteins and GSDMD-N protein (P<0.01). Whereas relevant to the model group, both the EA and medication groups had marked lower levels of Lequesne's score and synovial pathological score, serum IL-1ß and IL-18 contents, and expression levels of NLRP3, ASC, Caspase-1, IL-1ß, IL-18 mRNAs and proteins, GSDMD mRNA and GSDMD-N protein (P<0.01, P<0.05). Comparison between two intervention groups showed that the contents of serum IL-1ß and IL-18, and the expression levels of IL-1ß mRNA and protein were significantly higher in the EA group than in the medication group (P<0.05, P<0.01). No significant differences were found between the EA and medication groups in the Lequesne's score, synovial pathological score, NLRP3, ASC, Caspase-1 and IL-18 mRNAs and proteins, as well as GSDMD mRNA (P>0.05). CONCLUSION: EA can alleviate the inflammatory response of synovial tissues of knee joints in KOA rats, which may be related to its function in down-regulating the expression levels of synovial NLRP3, ASC, Caspase-1, IL-1ß and IL-18 mRNAs and proteins, and GSDMD mRNA and GSDMD-N proteins, reducing the occurrence of pyroptosis.

A novel nutritional mixture, MBN, prevents memory impairment via inhibiting NLRP3 inflammasome formation in 5xFAD transgenic mice.

OBJECTIVES: Amyloid beta (Aß)-induced abnormal neuroinflammation is recognized as a major pathological factor of Alzheimer's disease (AD), which results in memory impairment. Inhibition of excessive neuroinflammation mediated by Aß is considered a promising strategy to ameliorate AD symptoms. To regulate the inflammatory response, nutritional and dietary supplements have been used for centuries. Based on this idea, we investigated whether MBN, a novel nutritional mixture including cassia bark, turmeric root, and ginkgo leaf, can prevent AD progression through neuroinflammatory regulation. METHODS: MBN (10, 30, or 100 µg/ml) and Aß1-42 monomer were incubated together, and the degree of Aß aggregation was measured using Thioflavin T assay. The effects of MBN on Aß pathology in vivo were evaluated by orally administering MBN (40 mg/kg/day for 16 weeks) to five familial AD (5xFAD) mice. RESULTS: We found that treatment with MBN inhibited Aß aggregation in vitro. Next, MBN treatment significantly inhibited the activation of microglia induced by aggregated Aß in 5xFAD mice. Caspase-1 activation, which plays an important role in the maturation of interleukin-1ß, was markedly reduced by MBN. We also found that oral administration of MBN in 5xFAD mice alleviated memory decline. Taken together, our findings demonstrate that MBN suppresses neuroinflammation by downregulating the caspase-1 expression, thereby ameliorating memory impairment in 5xFAD mice. DISCUSSION: Based on these results, we suggest that MBN may be a preventive and therapeutic supplement for AD through the regulation of neuroinflammation.