FTO-mediated regulation of m6A methylation is closely related to apoptosis induced by repeated UV irradiation.

BACKGROUND: Ultraviolet (UV) damage is closely related to skin photoaging and many skin diseases, including dermatic tumors. N6-methyladenosine (m6A) modification is an important epigenetic regulatory mechanism. However, the role of m6A methylation in apoptosis induced by repeated UV irradiation has not been characterized. OBJECTIVE: To explore m6A methylation changes and regulatory mechanisms in the repeated UV-induced skin damage process, especially apoptosis. METHODS: HaCaT cells and BALB/c-Nu nude mice were exposed to repeated UVB/UVA+UVB irradiation. Colorimetry and flow cytometry were used to measure cellular viability and apoptosis. m6A-modified genes were detected via colorimetry and methylated RNA immunoprecipitation (MeRIP) sequencing. Methyltransferases and demethylases were detected via RT-PCR, western blotting and immunohistochemistry. Transfection of siRNA and plasmid was performed to knock down or overexpress the selected genes. RESULTS: After UVB irradiation, 861 m6A peaks were increased and 425 m6A peaks were decreased in HaCaT cells. The differentially modified genes were enriched in apoptosis-related pathways. The m6A demethylase FTO was decreased in both HaCaT cells and mouse skin after UV damage. Overexpressing FTO could improve cell viability, inhibit apoptosis and decrease RNA-m6A methylation, including LPCAT3-m6A, which increase LPCAT3 expression, cell viability promotion and apoptosis inhibition. CONCLUSION: Our study identified the cell m6A methylation change lists after repeated UVB irradiation, and revealed that FTO and LPCAT3 play key roles in the m6A methylation pathogenesis of UV-induced skin cell apoptosis. FTO-m6A-LPCAT3 might serve as a novel upstream target for preventing and treating photoaging and UV-induced skin diseases.

Co-expression of Xylose Transporter and Fructose-Bisphosphate Aldolase Enhances the Utilization of Xylose by Lactococcus lactis IO-1.

The raw material cost of lactic acid fermentation accounts for the main part of the production cost, and this necessitates the exploration of the efficient use of cheap raw materials in lactic acid production. We compared the outcomes of the homologous expressions of xylose transporters (xylFGH, xylE, araE, and xylT), 6-phosphofructokinase (pfkA), fructose-bisphosphate aldolase (fbaA), and their co-expression in Lactococcus lactis IO-1 on lactic acid production using xylose as the raw material. We found that the production rate of lactic acid on xylose fermentation by L. lactis IO-1 overexpressing fbaA was the highest (14.42%). Among the xylose transporters investigated, XylT had the strongest xylose transport capacity in L. lactis IO-1, with an increase in the lactic acid production rate by 10.38%. The genes near the overexpression of fbaA or xylT in the metabolic pathway were more upregulated than the distant genes. The co-expression of fbaA and xylT increased the production rate of lactic acid by 27.84% on xylose fermentation by L. lactis IO-1. This work presents a novel strategy for the simultaneous enhancement of the expression of important genes at the beginning and midway of the xylose metabolic pathway of L. lactis IO-1, which could greatly improve the target production.

Analysis of risk factors for early death in patients with acute promyelocytic leukaemia treated with arsenic trioxide.

To date, no specific studies have evaluated early death (ED) in patients with acute promyelocytic leukaemia (APL) homogeneously treated with arsenic trioxide induction therapy and investigated according to the white blood cell (WBC) count at onset. Such patients were retrospectively analysed in this study, including 314 patients with a WBC count ≤ 10 × 109/L (standard-risk (SR) group) and 144 with a WBC count > 10 × 109/L (high-risk (HR) group). The baseline clinical characteristics and risk factors for ED were compared between the two groups. The incidence of fibrinogen < 1.0 g/L and elevated serum uric acid, aspartate aminotransferase and creatinine levels were higher in the HR group than in the SR group (P = 0.001; P < 0.001; P < 0.001; P = 0.044, respectively). The ED rate was significantly higher in the HR group than in the SR group (29.17% vs. 10.83%, P < 0.001). The main cause of ED was bleeding, followed by infection and differentiation syndrome (DS) in the HR group, while it was bleeding, followed by DS and infection in the SR group. Male sex, age > 50 years old, and fibrinogen < 1.0 g/L were independent risk factors for ED in the SR group. Increased serum creatinine levels, decreased albumin levels, and fibrinogen < 1.0 g/L were independent risk factors for ED in the HR group. Overall, the incidence of ED was higher in the HR group, and the baseline clinical characteristics, causes, times, and predictors of ED in the HR group differed from those in the SR group.

Assessment of Skin Photoallergy Risk in Cosmetics Containing Herbal Extract Ingredients.

BACKGROUND/OBJECTIVE: In recent years, herbal extracts are becoming increasingly popular ingredients added in cosmetics; however, the assessment of their potential adverse effects on the skin remains unclear. As Coptis, Phellodendron amurense, curcumin, and shikonin are herbs currently used in cosmetic ingredients, the aim of this study was to assess their skin photoallergy (PA) potential and the concentrations at which they could safely be used. METHODS: In the patch test, Coptis, P. amurense, curcumin, and shikonin with 5, 10, 25, and 50% concentration were applied on 33 healthy Chinese subjects using the T.R.U.E. TEST® patch test system for 48 h. Photopatch testing was performed on 206 Chinese subjects with predisposed photosensitivity history using the Scandinavian photopatch series, and subjects were irradiated by 50% UVA minimum erythema dose. Photopatch testing of herbal extracts was then performed on subjects diagnosed with PA. RESULTS: Thirty-three subjects (14 with type III skin and 19 with type IV skin) completed contact patch testing of herbal extracts. Coptis induced a contact allergy (CA) reaction on 2 subjects at 25% concentration and on 2 subjects at 10% concentration. P. amurense induced a CA reaction on 1 subject at 10% concentration and on 1 subject at 5% concentration. Shikonin induced a stimulating reaction on 1 subject at 10% concentration. Curcumin induced a stimulating reaction on 1 subject at 10% concentration. Of the 206 Chinese subjects predisposed for photosensitivity, 10.19% had PA, 16.5% showed CA, and 1.45% had both PA + CA. PA-induced substances were promethazine hydrochloride (15%, n = 31), chlorpromazine hydrochloride (10.84%, n = 19), perfume mix (5.82%, n = 12), atranorin (3.39%, n = 7), 6-methyl coumarine (3.39%, n = 7), balsam Peru (1.94%, n = 4), fentichlor (1.94%, n = 4), 3,3',4',5-tetrachloro salicylanilide (0.97%, n = 2), hexachlorophene (0.97%, n = 2), chlorhexidine digluconate (0.97%, n = 2), and 4-aminobenzoic acid 2-hydroxy-4-methoxybenzophenone (0.97%, n = 2). Coptis at 25, 10, and 5% concentration and P. amurense, shikonin, and curcumin each at 10 and 5% concentration induced negative photopatch test results in all 10 photosensitive subjects. CONCLUSION: We have shown that Coptis, shikonin, or curcumin at 5% concentration in cosmetics could be applied safely without inducing contact allergic and photosensitive reactions on the skin. These findings advance the understanding of herbal extract use in cosmetic ingredients as related to the fields of dermatopharmacology and dermatotoxicology.

Identification and biological analysis of LncSPRY4-IT1-targeted functional proteins in photoaging skin.

BACKGROUND/PURPOSE: Skin photoaging, main causes of skin aging, is induced by chronic UV irradiation. LncSPRY4-IT1, a broadly expressed lncRNA, takes part in various biological functions by combining with functional protein molecules. However, the role of LncSPRY4-IT1 in skin photoaging process has not been characterized. This study is to investigate the interacting proteins of LncSPRY4-IT1 by combining RNA pull-down, high-throughput, and bioinformatic analysis. METHODS: Human skin fibroblasts (HDFs) were exposed to 10 J/cm2 UVA irradiation, once a day for 14 days. LncSPRY4-IT1 expression was qualified via RT-PCR. In vitro RNA pull-down assays and liquid chromatography-mass spectrometry analysis were used to identify the LncSPRY4-IT1-related proteins. Functional annotation analysis and pathway enrichment were preformed via Gene Ontology and KEGG. RESULTS: LncSPRY4-IT1 expression in photoaging fibroblasts was increased 1.66 ± 0.23 folds. 181 LncSPRY4-IT1-interacting proteins in UVA-induced photoaging skin fibroblast irradiation were identified, of which 56 proteins with two or more unique peptides, 73 proteins related to RNA processing, and 5 proteins related to DNA processing. High-throughput and bioinformatic analysis showed that LncSPRY4-IT1-targeting proteins were involved in cellular process, metabolic process, biological regulation, and cell part in skin photoaging process. The KEGG revealed that LncSPRY4-IT1-targeting proteins were mainly enriched in metabolic pathways. CONCLUSION: The results of our studies illuminate how LncSPRY4-IT1 formed a LncRNA-protein regulatory network in skin photoaging mechanisms and suggest that LncSPRY4-IT1 may serve as a novel upstream intervention target for the prevention and treatment of photoaging and related skin diseases.

Tissue factor-bearing microparticles are a link between acute promyelocytic leukemia cells and coagulation activation: a human subject study.

Acute promyelocytic leukemia (APL) cells constitutively express a large amount of tissue factor (TF) antigen, most of which is present in the cytoplasm. Coagulopathy may persist after induction therapy. We evaluated the overall role of circulating microparticles (MPs) in coagulation activation in APL-associated coagulopathy before and during induction therapy. Eleven adult patients with ≥ World Health Organization's (WHO) grade 2 bleeding events and 11 sex- and age-matched healthy controls were selected. All patients received arsenic trioxide alone as induction therapy. MP-associated TF (MP-TF) activity and MP procoagulant activity (MP-PCA) and 12 coagulation- and anticoagulation-associated indexes were measured before, during, and after induction therapy. Correlation between MP-associated indexes and the other 12 indexes was analyzed in patients. The MP-TF activity was negligible in controls, whereas it markedly increased in patients, dropped rapidly after treatment, and returned to normal at the end of induction therapy. The MP-PCA was similar between patients and controls. The correlation analysis revealed that TF-bearing MPs in patients mainly originated from APL cells. Partially differentiated APL cells could also release TF-bearing MPs, and the higher the degree of APL cell differentiation, the lower the ability of APL cells to release TF-bearing MPs. MP-TF was the main source of active TF in plasma and an important contributor for the coagulation activation in APL-associated coagulopathy. It was MPs released by APL cells/partially differentiated APL cells that served as the vehicle to transfer the large amount of TF to plasma to activate coagulation.

Comparative analysis of causes and predictors of early death in elderly and young patients with acute promyelocytic leukemia treated with arsenic trioxide.

PURPOSE: Early death (ED) is the main cause of acute promyelocytic leukemia (APL) treatment failure, and the ED rate is higher for elderly patients than that for young ones. To date, no studies have been found focusing on ED in elderly patients with APL. METHODS: This study retrospectively analyzed the clinical data of 409 consecutive patients with APL (139 patients ≥ 50 years old, 270 patients < 50 years old). All patients received arsenic trioxide alone as induction therapy. The baseline clinical characteristics and ED occurrence and predictors between elderly and young patients with APL were compared and analyzed. RESULTS: The clinical features of elderly patients at admission were not significantly different from those of young ones. The ED rate of elderly patients was significantly greater than that of young patients (23.74% vs 11.85%, P = 0.0018). Hemorrhage is the main cause of ED in elderly patients, followed by infection and differentiation syndrome. From the 15th to 30th days of treatment, elderly patients had a higher mortality rate than that of young patients (7.83% vs 2.06%, P = 0.009). Male, white blood cell (WBC) count > 10 × 109/L, fibrinogen < 1.0 g/L and low albumin levels were independent risk factors for ED in elderly patients, while ED was only correlated with WBC count, fibrinogen and creatinine levels in young patients. CONCLUSION: The results of this study may help design more rational treatment plans for elderly patients with APL based on early mortality risk to reduce the ED rate.

Factors affecting thrombohemorrhagic early death in patients with acute promyelocytic leukemia treated with arsenic trioxide alone.

Acute promyelocytic leukemia (APL) is often accompanied by a potentially devastating coagulopathy. Predictors of thrombohemorrhagic early death (TH-ED)/early bleeding death are not well characterized. In this retrospective study, eleven baseline clinical variables that can be assessed easily and promptly were chosen for evaluation in a cohort of 364 patients with APL who were administered arsenic trioxide (ATO) alone as remission induction therapy. TH-ED was defined as death from bleeding or thrombosis within 30 days after hospital admission. Cox proportional hazards regression model was used for both the univariate and multivariate analyses. Totally, 53 patients died from severe bleeding (51 cases) or thrombosis (2 cases), and at 30 days the cumulative incidences of TH-ED were 14.6%. Six independent risk factors for TH-ED were identified, including relapse, male, white blood cell (WBC) count above 10 × 109/L, fibrinogen level below 1 g/L, D-dimer level above 4 mg/L and increased creatinine level. Increased creatinine level was the most powerful risk factor, followed by WBC count > 10 × 109/L. This study identified risk factors for TH-ED in a large cohort of patients with APL, which enriched clinical information on identifying patients at high risk of TH-ED.

Development of a risk grading system to identify patients with acute promyelocytic leukemia at high risk of early death.

BACKGROUND: Early death (ED) rate in acute promyelocytic leukemia (APL) remains high. Some studies have identified prognostic factors capable of predicting ED, whereas no risk rating system for ED has been reported in the literature. In this study, a risk classification system was built to identify subgroup at high risk of ED among patients with APL. METHODS: Totally, 364 consecutive APL patients who received arsenic trioxide as induction therapy were included. Ten baseline clinical characteristics were selected for analysis, and they were de novo/relapse, age, sex, white blood cell count, platelet count, serum fibrinogen, creatinine, uric acid, aspartate aminotransferase, and albumin. Using a training cohort (N=275), a multivariable logistic regression model was constructed, which was internally validated by the bootstrap method and externally validated using an independent cohort (N=89). Based on the model, a risk classification system was designed. Then, all patients were regrouped into de novo (N=285) and relapse (N=79) cohorts and the model and risk classification system were applied to both cohorts. RESULTS: The constructed model included 8 variables without platelet count and sex. The model had excellent discriminatory ability (optimism-corrected area under the receiver operator characteristic curve=0.816±0.028 in the training cohort and area under the receiver operator characteristic curve=0.798 in the independent cohort) and fit well for both the training and independent data sets (Hosmer-Lemeshow test, P=0.718 and 0.25, respectively). The optimism-corrected calibration slope was 0.817±0.12. The risk classification system could identify a subgroup comprising ~25% of patients at high risk of ED in both the training and independent cohorts (OR=0.140, P<0.001 and OR=0.224, P=0.027, respectively). The risk classification system could effectively identify patient subgroups at high risk of ED in not only de novo but also relapse cohorts (OR=0.233, P<0.001 and OR=0.105, P=0.001, respectively). CONCLUSION: All the results highlight the high practical value of the risk classification system.

Characteristics of fibrinolytic disorders in acute promyelocytic leukemia.

OBJECTIVES: Catastrophic hemorrhage remains the main cause of acute promyelocytic leukemia (APL) treatment failure. This study was aimed to study the pathogenesis of coagulopathy in patients with APL. METHODS: Multiple procoagulant and profibrinolytic parameters in plasma and peripheral leukocytes from 24 patients with newly diagnosed APL accompanied by coagulopathy before and after arsenic trioxide (ATO) treatment were evaluated. RESULTS: Prior to the treatment, the patients had elevated D-dimer and decreased fibrinogen levels. Plasma urokinase-type plasminogen activator receptor (uPAR) and plasmin-ɑ2 antiplasmin complexes (PAP) levels, plasmin (Pn) activity, and cell surface levels of urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA) were significantly higher; plasma plasminogen activator inhibitor-1 (PAI-1) levels and plasminogen (Pg) activity were significantly decreased; plasma plasminogen activator (PA) activity, uPA and tPA levels; and cell surface levels of uPAR and annexin II were not significantly different from levels in the control group. During ATO treatment, both patients' plasma PA activity and uPAR on leukocytes gradually increased, annexin II on leukocytes increased initially and decreased afterwards, and tPA and uPA on leukocytes remained consistently higher in the patients than in the controls. Other parameters gradually tended toward normal values. CONCLUSIONS: In APL, activated coagulation system activated fibrinolytic system, and increased uPAR levels could contribute to the hyperfibrinolysis. Annexin II might not be involved in the coagulopathy.

Difference in causes and prognostic factors of early death between cohorts with de novo and relapsed acute promyelocytic leukemia.

Early death (ED) remains the most critical issue in the current care of patients with acute promyelocytic leukemia (APL). Very limited data are available regarding ED in patients with relapsed APL. In this retrospective study, 285 de novo and 79 relapsed patients were included. All patients received single-agent arsenic trioxide as induction therapy. The differences in baseline clinical features, incidence, causes, and prognostic factors of ED were compared between the two patient cohorts. The relapse cohort exhibited a better overall condition than the de novo cohort upon hospital admission. The ED rate in the relapsed patients (24.1%) was somewhat higher than that in the de novo patients (17.9%), although the difference was not significant (P = 0.219). For both cohorts, hemorrhage was the main cause of ED, followed by differentiation syndrome, infection, and other causes. Increased serum creatinine level, older age, male sex, white blood cell (WBC) count > 10 × 109/L, and fibrinogen < 1 g/L were independently risk factors for ED in the de novo patients, whereas WBC count > 10 × 109/L, elevated serum uric acid level, and D-dimer > 4 mg/L were independent risk factors for ED in the relapsed patients. These data furnish clinically relevant information that might be useful for designing more appropriate risk-adapted treatment protocols aimed at reducing ED rate in patients with relapsed APL.

Causes and prognostic factors for early death in patients with acute promyelocytic leukemia treated with single-agent arsenic trioxide.

Early death (ED) is one of the most critical issues involved in the current care of patients with acute promyelocytic leukemia (APL). Factors identified as independent predictors of ED varied among published studies. We retrospectively analyzed the incidence, causes, and prognostic factors of ED in a series of 216 patients with newly diagnosed APL who received arsenic trioxide (ATO) as induction therapy. Multivariate logistic regression analysis was used to determine the association of clinical factors with overall ED, hemorrhagic ED, death within 7 days, and death within 8-30 days. In total, 35 EDs (16.2%) occurred that were caused by hemorrhage, differentiation syndrome (DS), infection, and other causes, in order of prevalence. The independent prognostic factors for overall ED and death within 8-30 days were the same and included serum creatinine level, Eastern Cooperative Oncology Group (ECOG) score, sex, and fibrinogen level. The risk factors for hemorrhagic ED and death within 7 days were similar and included serum creatinine level, ECOG score, and white blood cell count, while hemorrhagic ED was also associated with D-dimer. Our findings revealed a high rate of ED, and the causes of ED were similar to those among patients who received ATRA-based therapy. Increased creatinine level was the most powerful predictor, and an ECOG score greater than 2 was another strong prognostic factor for all four types of ED.

Palladium-Catalyzed α-Arylation of Cyclic Vinylogous Esters for the Synthesis of γ-Arylcyclohexenones and Total Synthesis of Aromatic Podocarpane Diterpenoids.

Described is a method for the formal γ-arylation of cyclohexenones allowing synthesis of a remote all-carbon quaternary center. The process involves the palladium-catalyzed α-arylation of a α-substituted cyclic vinylogous ester followed by the Stork-Danheiser transposition. The synthetic utility of this protocol is featured in the total syntheses of (±)-12-hydroxy-13-methylpodocarpa-8,11,13-trien-3-one, (±)-3ß,12-dihydroxy-13-methylpodocarpane-8,11,13-triene, and (±)-O-methyl nimbinone.

Mechanical behaviors of carbon nanotubes with randomly located vacancy defects.

In this paper, (10, 0) zigzag nanotubes and (6, 6) armchair nanotubes are considered to investigate the effects of randomly distributed vacancy defects on mechanical behaviors of single-walled carbon nanotubes. A spatial Poisson point process is employed to randomly locate vacancy defects on nanotubes. Atomistic simulations indicate that the presence of vacancy defects result in reducing nanotube strength but improving nanotube bending stiffness. In addition, the studies of nanotube torsion indicate that vacancy defects prevent nanotubes from being utilized as torsion springs.