Dexmedetomidine suppressed the biological behavior of RAW264.7 cells treated with LPS by down-regulating HOTAIR.

Background: Previous studies have revealed dexmedetomidine have potential protective effects on vital organs by inhibiting the release of inflammatory cytokines. To investigate the effects of dexmedetomidine on sepsis, especially in the initial inflammatory stage of sepsis. RAW264.7 cells were used as the cell model in this study to elucidate the underlying mechanisms. Methods: In this study, we conducted several assays to investigate the mechanisms of dexmedetomidine and HOTAIR in sepsis. Cell viability was assessed using the CCK-8 kit, while inflammation responses were measured using ELISA for IL-1ß, IL-6, and TNF-α. Additionally, we employed qPCR, MeRIP, and RIP to further explore the underlying mechanisms. Results: Our findings indicate that dexmedetomidine treatment enhanced cell viability and reduced the production of inflammatory cytokines in LPS-treated RAW264.7 cells. Furthermore, we observed that the expression of HOTAIR was increased in LPS-treated RAW264.7 cells, which was then decreased upon dexmedetomidine pre-treatment. Further investigation demonstrated that HOTAIR could counteract the beneficial effects of dexmedetomidine on cell viability and cytokine production. Interestingly, we discovered that YTHDF1 targeted HOTAIR and was upregulated in LPS-treated RAW264.7 cells, but reduced in dexmedetomidine treatment. We also found that YTHDF1 increased HOTAIR and HOTAIR m6A levels. Conclusions: Collectively, our results suggest that dexmedetomidine downregulates HOTAIR and YTHDF1 expression, which in turn inhibits the biological behavior of LPS-treated RAW264.7 cells. This finding has potential implications for the prevention and treatment of sepsis-induced kidney injury.

Expression of peptidylarginine deiminase 4 and protein tyrosine phosphatase nonreceptor type 22 in the synovium of collagen-induced arthritis rats.

OBJECTIVE: To study the expression level of peptidylarginine deiminase 4 (PADI4) and protein tyrosine phosphatase nonreceptor type 22 (PTPN22) in the synovium of rat model of collagen-induced arthritis, and to explore their possible therapeutic role in rheumatoid arthritis. METHODS: Thirty-two female Wistar rats weighing 100±20 g were randomly assigned into 3-week collagen-induced arthritis (CIA) model group (n=8), 4-week CIA model group (n=8), 6-week CIA model group (n=8), and the control group (n=8). The body weight changes of each group were recorded. The expression levels of PADI4 and PTPN22 were detected and compared by the methods of immunohistochemical staining and Western blot. RESULTS: Arthritis of rat began to form 14 days after sensitization and the joint swelling reached peak at 28 days. The weights of the rats slowly grew both in CIA model groups and the control group. Immunohistochemical staining results showed that the positive expression of PADI4 and PTPN22 was mainly located in cartilage peripheral mononuclear cells, the cytoplasm of infiltrated cells, and bone marrow cavity. There were significant differences in the optical density of PADI4 and PTPN22 among CIA model groups and the control group (PADI4, 0.2898±0.012, 0.2982±0.022, 0.2974±0.031, 0.2530±0.013 in 3-week CIA model, 4-week CIA model, 6-week CIA model and control groups; PTPN22, 0.2723±0.004, 0.2781±0.010, 0.2767±0.008, 0.2422±0.019; all P <0.05). The expression bands of PADI4 were observed in Western blot 3 weeks after initial immunization, the thickest in the 4th week, and decreased in the 6th week. The expression bands of PTPN2 were observed at all the time points, with no obvious time-dependent trend. CONCLUSIONS: PADI4 and PTPN22 are obviously correlated with CIA in rat model. PADI4 is expressed at early stage of the disease, while the expression of PTPN22 sustains throughout the course.

Increased interleukin-23 is associated with increased disease activity in patients with rheumatoid arthritis.

BACKGROUND: Interleukin-23 (IL-23) is a pro-inflammatory cytokine that is thought to be central to the development of autoimmune diseases. This study was conducted to determine whether or not the serum concentration of IL-23 is elevated in patients with rheumatoid arthritis (RA), and to determine the relationship between the IL-23 level and disease activity in RA patients. METHODS: Serum samples were obtained from 59 patients with RA and 30 healthy controls. The clinical parameters of disease activity were determined, including the 28-joint disease activity score (DAS28), C-reactive protein (CRP), rheumatoid factor (RF) levels, and the degree of bony erosions based on X-rays. The levels of IL-23 and IL-17 were determined by enzyme-linked immunosorbent assay (ELISA). The correlations between the serum levels of IL-23 and disease activity parameters of patients with RA were determined. RESULTS: The serum IL-23 level was significantly elevated in patients with RA compared to healthy controls. The serum IL-23 levels in the RA patients correlated with IL-17 and CRP levels, and the DAS28. The levels of IL-23 based on X-ray classification phase I, II, III, and IV were gradually elevated in RA patients. CONCLUSIONS: The levels of serum IL-23 in RA patients were higher than in healthy controls. Thus, elevated serum IL-23 levels may be useful markers to detect active RA. In addition, IL-23 is involved in disease progression and bony erosions in patients with RA.

[Determination of trace copper (II) based on fluorescence quenching of NaGdF4 : Eu nanoparticles].

Water-soluble NaGdF4 : Eu fluorescent nanoparticles modified by citrate were synthesized by hydrothermal method with stable fluorescent properties. It was found that the fluorescence of the solution of as-prepared particles could be quenched by Cu2+, and thus a new mathod to determine trace Cu2+ using NaGdF4 : Eu as fluorescent probe was established. A pH 10.0 and the concentration 1.0 x 10(-3) mol x L(-1) of NaGdF4 : Eu were selected for measurement Besides, the effect of some foreign ions on the fluorescence signals was investigated and the interference of Fe3+ was found, which was eliminated by adding triethanolamine. The regression equation of standard curve was I = 532-0.685c with the correlation coefficient of -0.998 4 when the concentration of Cu2+ was in the range of 3.33 x 10(-6) -1.33 x 10(-4) mol x L(-1), and the detection limit of 8.9 x 10(-7) mol x L(-1) and a RSD of 0.62% for 11 replicates of a 6.0 x 10(-5) mol x L(-1) Cu2+ solution were obtained, which suggest a wide linear analytical range, high sensitivity and high precision. Analytical applicability of the particles was demonstrated by tea sample analysis and the results of Cu2+ determination were in good agreement with those obtained by atomic absorption spectrometry. The reason for fluorescence quenching by Cu2+ can be explained in terms of combination of Cu2+ with citrate on the surface of NaGdF4 : Eu particles leading to a change in surface structure and the composition.