Paeoniflorin regulates RhoA/ROCK1 and Nrf2 pathways in PDLIM1-dependent or independent manners in oxidative stressed melanocytes.

BACKGROUND: The adhesive properties of vitiligo melanocytes have decreased under oxidative stress., cytoskeleton proteins can control cell adhesion. Paeoniflorin (PF) was proved to resist hydrogen peroxide (H2O2)-induced oxidative stress in melanocytes via nuclear factorE2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. OBJECTIVES: This study was to investigate whether PF exerts anti-oxidative effect through influencing cytoskeleton markers or potential signaling pathway. METHODS: Human Oxidative Stress Plus array was used to identify the differentially expressed genes between H2O2 + PF group and H2O2 only group, in PIG1 and PIG3V melanocyte cell lines respectively. Western blotting was used to verify the PCR array results and to test the protein expression levels of cytoskeleton markers including Ras homolog family member A (RhoA), Rho-associated kinase 1 (ROCK1) and antioxidative marker Nrf2. Small interfering RNA was used to knock down PDZ and LIM domain 1 (PDLIM1). RESULTS: PF increased the expressions of PDLIM1, RhoA and ROCK1 in H2O2-induced PIG1, in contrast, decreased the expressions of PDLIM1 and ROCK1 in H2O2-induced PIG3V. Knockdown of PDLIM1 increased the expressions of RhoA and Nrf2 in PF-pretreated H2O2-induced PIG1, and ROCK1 and Nrf2 in PF-pretreated H2O2-induced PIG3V. CONCLUSIONS: PF regulates RhoA/ROCK1 and Nrf2 pathways in PDLIM1-dependent or independent manners in H2O2-induced melanocytes. In PIG1, PF promotes PDLIM1 to inhibit RhoA/ROCK1 pathway or activates Nrf2/HO-1 pathway, separately. In PIG3V, PF directly downregulates ROCK1 in PDLIM1-independent manner or upregulates Nrf2 dependent of PDLIM1.

Causal effects of fatty acids on atopic dermatitis: A Mendelian randomization study.

Background: Some evidence suggests abnormalities in fatty acids in patients with atopic dermatitis (AD), and benefits of supplementation with these fatty acids have been reported. However, there is still substantial controversy on the correlation between fatty acids and AD. Therefore, the aim of this study was to determine whether fatty acid levels are causally related to AD using a Mendelian randomization approach. Methods: We evaluated the data about the fatty acids levels and AD with various methods from Genome-Wide Association Study (GWAS). GWAS results were available both from European ancestry. Mendelian randomization methods were used to analysis the casual inference of fatty acids on AD. MR Egger and MR-PRESSO were used to determine pleiotropy and heterogeneity. Further analysis was conducted using instruments associated with the FADS genes to address mechanisms involved. We also used Multivariate MR (MVMR) to show the independent casual inference of omega-3 (n-3) fatty acids on AD. Results: Mendelian randomization (MR) analysis suggests that n-3 fatty acid levels are associated with a lower risk of AD (n-3 ORIVW: 0.92, 95% confidence interval [CI]: 0.87-0.98; p = 0.01). Moreover, docosahexaenoic acids (DHA) levels, which is a kind of long-chain, highly unsaturated omega-3 (n-3) fatty acid, and its higher level was associated with a lower risk of AD (DHA ORIVW: 0.91, 95% CI: 0.84-0.98; p = 0.02). We ran multivariable MR analysis while controlling for variables within the other types of fatty acids. The effect estimates agreed with the preliminary MR analysis indicating the effect of n-3 fatty acids levels on AD was robust. MR-egger suggest no significant pleiotropy and heterogeneity on genetic instrumental variants. Outliers-corrected MR analyses after controlling horizontal pleiotropy were still robust. The single-SNP analyses revealed that n-3 fatty acids are likely linked to a decreased risk of AD through FADS cluster, highlighting the significance of the FADS gene in the fatty acids synthesis pathway in the development of AD. Conclusion: Our studies suggest that n-3 fatty acids may reduce the risk of AD. Risk prediction tools based on n-3 fatty acid levels may be valuable methods for improving AD screening and primary prevention. To reduce the risk of AD, individuals could enhance n-3 fatty acids intake through supplement or diet.

DnaJA4 is involved in responses to hyperthermia by regulating the expression of F-actin in HaCaT cells.

BACKGROUND: Hyperthermia in combination with DnaJA4-knockout (KO) obviously affects the anti-viral immunity of HaCaT cells. The mechanisms of this process are not yet fully explored. However, it is known that DnaJA4 interacts with actin cytoskeleton after hyperthermia. Our aim was to investigate the effects of DnaJA4 on F-actin in HaCaT cells following hyperthermia. METHODS: Wild-type (WT) and DnaJA4-KO HaCaT cells were isolated at either 37°C (unheated) or 44°C (hyperthermia) for 30 min followed by testing under conditions of 37°C and assessing at 6, 12, and 24 h after hyperthermia. The cytoskeleton was observed with immunofluorescence. Flow cytometry and Western blotting were used to detect the expression of F-actin and relevant pathway protein. RESULTS: DnaJA4-KO and hyperthermia changed the cytoskeleton morphology of HaCaT cells. F-actin expression levels were elevated in DnaJA4-KO cells compared with WT cells (6364.33 ±â€Š989.10 vs. 4272.67 ±â€Š918.50, P < 0.05). In response to hyperthermia, F-actin expression levels of both WT and DnaJA4-KO cells showed a tendency to decrease followed by an obvious recovery after hyperthermia (WT cells: unheated vs. 6 h after hyperthermia or 24 h after hyperthermia: 0.34 ±â€Š0.02 vs. 0.24 ±â€Š0.01, 0.31 ±â€Š0.01, P < 0.001, P < 0.05; DnaJA4-KO cells: unheated vs. 6 h after hyperthermia or 24 h after hyperthermia: 0.44 ±â€Š0.01 vs. 0.30 ±â€Š0.01, 0.51 ±â€Š0.02, P < 0.001, P < 0.01). WT cells restored to baseline levels observed in the unheated condition, while DnaJA4-KO cells exceeded baseline levels in the recovery. As the upstream factors of F-actin, a similar profile in rho-associated serine/threonine kinase 1 (ROCK 1) and RhoA expressions was observed after hyperthermia. While E-cadherin expression was decreased in response to hyperthermia, it was increased in DnaJA4-KO cells compared with WT cells. CONCLUSIONS: Hyperthermia affects the expression levels of F-actin in HaCaT cells. DnaJA4 knockout increases the expression of F-actin in HaCaT cells after hyperthermia. DnaJA4 regulates the expressions of F-actin and the related pathway proteins in response to hyperthermia in HaCaT cells.

UVA Induced Oxidative Stress Was Inhibited by Paeoniflorin/Nrf2 Signaling or PLIN2.

Photodamages caused by UVA radiation induced oxidative injuries are closely related to photoaging and skin cancer. Paeoniflorin (PF), extracted from the root of Paeonia lactiflora, has been reported to be an effective antioxidant. PLIN2, known as adipose differentiation-related protein, has been previously involved in the regulation of oxidative stress. In this study, we were sought to investigate the photo-protective property of PF and PLIN2 in UVA-radiated human dermal fibroblasts (HDFs). HDFs were pre-treated with PF (800 µM) followed by UVA radiation (22.5 J/cm2). MTS activity, cell apoptosis, ROS, MDA, and SOD were detected, respectively. The expressions of Nrf2, HO-1, NQ-O1, and PLIN2 were determined using RT-qPCR or western blot. Nrf2 was silenced by siRNA, and PLIN2 was overexpressed via lentiviral transduction. Comparing to the UVA radiation, PF pre-treatment could prominently increase the MTS activity, decrease cell apoptosis, reduce the generations of ROS and MDA, increase the activity of SOD and increase the expression of Nrf2 and its target genes HO-1 and NQ-O1. When Nrf2 was knocked down, PF lost above protective properties. In addition, UVA induced oxidative stress led to upregulation of PLIN2 and the latter could be decreased by PF. Overexpression of PLIN2 improved MTS activity and reduced MDA level in HDFs. The combination of PLIN2 overexpression and PF pre-treatment corporately inhibited UVA-induced injury. Besides, we also found that PF and PLIN2 had a compensatory protection against UVA induced oxidative stress. In conclusion, our study demonstrated that UVA induced photodamages could be inhibited by PF via Nrf2/HO-1/NQ-O1 signaling pathway or by PLIN2, and the combination of PLIN2 overexpression and PF played additive effects against UVA-related oxidative stress.

Spectrum and antimicrobial resistance of common pathogenic bacteria isolated from patients with acute exacerbation of chronic obstructive pulmonary disease in mainland of China.

BACKGROUND: Bacteria-induced respiratory infection has been long considered to be the major cause of acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Therefore, a clear picture about the distribution and drug-resistance of pathogenic bacteria in the lower airways should be helpful for treatment of the disease. So far, data on this topic among Chinese are lacking. METHODS: A surveillance study was performed in consecutive patients with AECOPD at five areas in China between October 2006 and April 2008. The sputum from these patients was cultured and isolated for bacteria. Agar dilution method was used to determine the minimal inhibitory concentrations (MICs) of levofoxacin and other 15 antibiotics against these strains. RESULTS: Three hundred and fifty-nine pathogenic bacterial strains were isolated among 884 patients with AECOPD. The predominant bacteria were Pseudomonas aeruginosa (21.7%), Klebsiella pneumoniae (12.3%), Haemophilus influenzae (14.2%) and Streptococcus pneumoniae (11.7%), followed by Haemophilus parainfluenzae (9.5%), Acinetobacter baumannii (7.8%), Moraxella catarrhalis (6.4%) and Escherichia coli (3.6%). The majority of bacterial pathogens isolated in this study were susceptible to fuoroquinolones, ceftazidime, cefepime and imipenem. CONCLUSIONS: Gram-negative bacilli are the leading pathogens in patients with AECOPD in China. Haemophilus parainfluenzae may be one of the most important pathogens in AECOPD. This study provides evidence for local surveillance of AECOPD pathogens and appropriate choice of antimicrobials in China.

Protective effect of a bacterial extract against acute exacerbation in patients with chronic bronchitis accompanied by chronic obstructive pulmonary disease.

BACKGROUND: Immunostimulating agents made from bacterial extracts represent a class of medications that contains antigens derived from several bacterial strains and their potential ability to prevent bacterial infections results from the stimulation of the nonspecific component of the immune system. The present study investigated the effect of the oral immunostimulant Broncho-Vaxom, which includes material from eight different species of bacteria that are frequently present in the lower respiratory tract, on the frequency and severity of acute exacerbation in patients with chronic bronchitis accompanied by chronic obstructive pulmonary disease (COPD). METHODS: Ninety patients with chronic bronchitis complicated with COPD were randomly divided into groups A and B. Forty-nine subjects in group A received oral capsules containing 7 mg Broncho-Vaxom, while 41 patients in group B received similar placebo capsules. Both groups took one capsule daily for the first 10 days of each month for 3 consecutive months. The frequency of acute exacerbation, symptom scores, and lung function were recorded for the following one year period. RESULTS: There was a significant decrease in the incidence, duration, and severity of acute exacerbation, as well as a reduction in the course of antibiotics administered and in the dosage of bronchodilator and mucolytic agent in group A, as compared to group B (P < 0.05, respectively). Symptom scores for cough, sputum, dyspnea, as well as symptoms observed upon auscultation of the chest also improved significantly in group A as compared to group B (P < 0.05, respectively). The bacterial clearance rate in sputum cultures from patients who received no antibiotics for the first 3 months was also significantly higher in group A compared to group B (P < 0.01). CONCLUSIONS: Orally administered Broncho-Vaxom is associated with a decrease in the incidence of acute exacerbation and a decrease in the need for antibiotics and symptomatic relief medications in patients with chronic bronchitis accompanied by COPD. Broncho-Vaxom is also associated with a decrease in symptom scores. Without causing any apparent adverse effects, this drug may also help to eradicate pathogenic bacteria in the airways.