Circ_0000396 suppresses the proliferation and inflammation of rheumatoid arthritis synovial fibroblasts by targeting miR-574-5p/RSPO1 axis.

BACKGROUND: Circular RNAs (circRNAs) are important regulators on the onset and progression of rheumatoid arthritis (RA). Our purpose is to explore the role and underpin mechanism of circ_0000396 in RA progression. METHODS: RA patients (n = 39) and healthy volunteers (n = 33) were recruited from the Affiliated Hospital of Shaanxi University of Chinese Medicine for the present work. Circ_0000396, microRNA-574-5p (miR-574-5p) and R-spondin 1 (RSPO1) RNA levels were analyzed by reverse transcription-quantitative polymerase chain reaction. Cell proliferation was analyzed by 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, colony formation assay, and 5-ethynyl-2'-deoxyuridine (EDU) assay. Cell apoptosis was assessed by flow cytometry. Protein expression levels of proliferating cell nuclear antigen (PCNA), Cyclin D1, Cyclin E1, BCL2-associated × protein (Bax), B-cell lymphoma-2 (Bcl2), interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α) and RSPO1 were detected by western blot assay. Enzyme-linked immunosorbent assay (ELISA) was conducted to analyze the secretion of pro-inflammatory cytokines including IL-1ß and TNF-α. The interaction between miR-574-5p and circ_0000396 or RSPO1 was confirmed by dual-luciferase reporter assay and RNA-pull down assay. RESULTS: Circ_0000396 expression was notably down-regulated in RA patients compared with healthy controls. Circ_0000396 overexpression suppressed the proliferation and inflammatory response and triggered the apoptosis of RA synovial fibroblasts (RASFs), accompanied by decreases in PCNA, Cyclin D1, Cyclin E1, Bcl2, IL-1ß and TNF-α protein expression and an increase in Bax protein expression. Circ_0000396 acted as a molecular sponge for miR-574-5p, and circ_0000396 overexpression-mediated protective effects on RASFs dysfunction were largely reversed by the introduction of miR-574-5p mimics. miR-574-5p interacted with the 3' untranslated region (3'UTR) of RSPO1, and miR-574-5p negatively regulated RSPO1 expression in RASFs. Circ_0000396 could up-regulate the expression of RSPO1 by sponging miR-574-5p in RASFs. RSPO1 interference largely overturned circ_0000396 overexpression-mediated effects in RASFs. CONCLUSION: Circ_0000396 restrained the proliferation and inflammation and induced the apoptosis of RASFs by mediating miR-574-5p/RSPO1 axis, which provided novel potential targets for RA treatment.

Electroacupuncture Alleviates Osteoarthritis by Suppressing NLRP3 Inflammasome Activation in Guinea Pigs.

Osteoarthritis (OA) is an increasingly prevalent disease affecting synovial joints, which includes joint degeneration, inflammation, and joint pain. The activation of nucleotide-binding and oligomerization domain-like receptor containing protein 3 (NLRP3) could promote synovial inflammation. Previous studies have shown that electroacupuncture (EA) has potential anti-inflammatory effect. However, the effect of EA treatment on OA remains unclear. The aim of this study was to investigate the effect of applied EA on OA and joint pain and its relationship with NLRP3 inflammasome. The Hartley guinea pigs with naturally occurring OA at age 18 months were chosen as the OA model and treated with EA for 4 weeks. Mechanical allodynia was quantified by using von Frey filaments. The expression of NLRP3 inflammasome and the downstream proinflammatory factors in the cartilage tissue were quantified. Our results showed that EA treatment significantly reduces mechanical allodynia, improves the articular cartilage structure, and decreases the fibrillation on the cartilage surface in guinea pigs with spontaneous osteoarthritis. Moreover, we also found that EA treatment attenuates the NLRP3 inflammasome activation and suppresses the protein expression levels of caspase-1 and IL-1ß in the cartilage tissue. Our findings suggest that EA treatment attenuates OA and joint pain by suppressing NLRP3 inflammasome activation and support further investigation of the potential therapeutic tactics.

BiAg alloy nanospheres: a new photocatalyst for H2 evolution from water splitting.

We demonstrate for the first time that Bi and BiAg alloy nanospheres, fabricated with a facile hydrothermal method, display evident photocatalytic H2 production activities. Element Bi can serve as an active photocatalyst for both water splitting and photoelectrochemical applications. More interestingly, these activities of Bi can be greatly enhanced by introducing Ag to form BiAg alloy nanoparticles, which may be ascribed to the improved charge separation and enlarged carrier concentration. The constituent of the BiAg alloy can be rationally tuned by varying the amount of Ag nanowires, and it is found that Bi0.7Ag0.3 exhibits the highest photoelectrochemical property.

Morphology modulation of SrTiO3/TiO2 heterostructures for enhanced photoelectrochemical performance.

Design and fabrication of nanoscale semiconductors with regulatable morphology or structure has attracted tremendous interest due to the dependency relationship between properties and architectures. Two types of SrTiO3/TiO2 nanocomposites with different morphologies and structures have been fabricated by controlling the kinetics of hydrothermal reactions. One is TiO2 nanotube arrays densely wrapped by SrTiO3 film and the other is SrTiO3 nanospheres distributed on the top region of TiO2 nanotube arrays, which has been firstly fabricated. It has been found that the photoelectrochemical performances of these heterostructures are crucially dominated by their architectures. Heterostructured SrTiO3/TiO2 nanotube arrays were fabricated by traditional method in the absence of NaOH and they exhibited higher photoelectrochemical performance than pure TiO2 nanotube arrays. However, the compact SrTiO3 coating film on the sidewalls of TiO2 nanotube arrays could inevitably destroy the tubular structures of TiO2 and thus go against the vectorial transport of electrons. Interestingly, when excess NaOH was added into the growth solution, SrTiO3 nanospheres would be rationally grafted on the top of TiO2 nanotube arrays, which could preserve the tubular structures of TiO2, and thus further improve the photoelectrochemical performance.

Concave trisoctahedral Ag3PO4 microcrystals with high-index facets and enhanced photocatalytic properties.

Herein, we demonstrate for the first time the fabrication of concave trisoctahedral Ag(3)PO(4) microcrystals enclosed by {221} and {332} facets based on the heteroepitaxial growth procedure, which exhibit much higher photocatalytic activities than cubic Ag(3)PO(4) and commercial N-doped TiO(2).

Two-dimensional dendritic Ag3PO4 nanostructures and their photocatalytic properties.

Two-dimensional dendritic Ag(3)PO(4) nanostructures have been synthesized in high-yield by reacting Ag nanowires with H(2)O(2) and NaH(2)PO(4) in aqueous solution at room temperature, which exhibit much higher photocatalytic activities than irregular Ag(3)PO(4) nanocrystals and N-doped TiO(2) catalyst for the degradation of organic contaminants under visible light irradiation.

Preventive administration of juanbi capsules for knee osteoarthritis: effects on serum MMP-2 and MMP-9 levels and cartilage repair.

OBJECTIVE: To explore the mechanism of action of Juanbi Capsules, a Chinese medicine for invigorating the kidney and replenishing qi, in preventing osteoarthritis of the knee in rabbits. METHODS: Seventy-two 4-month-old, Japanese long-eared white rabbits were randomly divided into 6 groups: control (group A), model (group B), Chinese drug; high-dose (group C), Chinese drug; mid-dose (group D), Chinese drug; low-dose (group E), and drug control (group F). With the exception of the rabbits in group A, each rabbit was subjected to plaster cast fixation for 6 weeks to induce osteoarthritis. In addition, rabbits were administrated with an intragastric injection of the Chinese drug (groups C, D and E) or an aminoglucose hydrochloride capsule (group F) for 4 weeks. Blood was drawn from the central ear artery for serum MMP-2 and MMP-9 concentrations, and the knee joint cartilage was harvested for gross observation and light microscopy. RESULTS: There were significant differences in serum MMP-2 and MMP-9 concentrations between group B and groups C, D and E (P < 0.05), with no significant differences between groups D and F. Histological results showed various changes in tissue staining with treatment, with osteophyte and bone cyst formation, and superficial erosion in the articular surface of the cartilage; in some cases, the defect reached the mid-layer of the cartilage, and these changes were lower than those in the model group. CONCLUSION: Juanbi Capsules assist in preventing osteoarthritis in the rabbit, possibly by decreasing serum MMP-2 and MMP-9 levels.