Metronomic capecitabine inhibits liver transplant rejection in rats by triggering recipients' T cell ferroptosis.

BACKGROUND: Capecitabine (CAP) is a classic antimetabolic drug and has shown potential antirejection effects after liver transplantation (LT) in clinical studies. Our previous study showed that metronomic CAP can cause the programmed death of T cells by inducing oxidative stress in healthy mice. Ferroptosis, a newly defined non-apoptotic cell death that occurs in response to iron overload and lethal levels of lipid peroxidation, is an important mechanism by which CAP induces cell death. Therefore, ferroptosis may also play an important role in CAP-induced T cell death and play an immunosuppressive role in acute rejection after trans-plantation. AIM: To investigate the functions and underlying mechanisms of antirejection effects of metronomic CAP. METHODS: A rat LT model of acute rejection was established, and the effect of metronomic CAP on splenic hematopoietic function and acute graft rejection was evaluated 7 d after LT. In vitro, primary CD3+ T cells were sorted from rat spleens and human peripheral blood, and co-cultured with or without 5-fluorouracil (5-FU) (active agent of CAP). The levels of ferroptosis-related proteins, ferrous ion concentration, and oxidative stress-related indicators were observed. The changes in mito-chondrial structure were observed using electron microscopy. RESULTS: With no significant myelotoxicity, metronomic CAP alleviated graft injury (Banff score 9 vs 7.333, P < 0.001), prolonged the survival time of the recipient rats (11.5 d vs 16 d, P < 0.01), and reduced the infiltration rate of CD3+ T cells in peripheral blood (6.859 vs 3.735, P < 0.001), liver graft (7.459 vs 3.432, P < 0.001), and spleen (26.92 vs 12.9, P < 0.001), thereby inhibiting acute rejection after LT. In vitro, 5-FU, an end product of CAP metabolism, induced the degradation of the ferritin heavy chain by upregulating nuclear receptor coactivator 4, which caused the accumulation of ferrous ions. It also inhibited nuclear erythroid 2 p45-related factor 2, heme oxygenase-1, and glutathione peroxidase 4, eventually leading to oxidative damage and ferroptosis of T cells. CONCLUSION: Metronomic CAP can suppress acute allograft rejection in rats by triggering CD3+ T cell ferroptosis, which makes it an effective immunosuppressive agent after LT.

Integrative Multi-Omics Analysis of Identified Ferroptosis-Marker RPL8 as a Candidate Oncogene Correlates with Poor Prognosis and Immune Infiltration in Liver Cancer.

BACKGROUND: Liver Hepatocellular Carcinoma (LIHC) is characterized by high malignancy, poor prognosis, and high recurrence rate worldwide. The role of ferroptosis in tumorigenesis and progression has been confirmed in previous studies. However, the multi-omics analysis in liver cancer of ferroptosis-markers RPL8 remains to be elucidated. METHODS: In this analysis, the RPL8 mRNA expression was analyzed via the GEPIA, TIMER and UALCAN databases. In addition, we verified the mRNA expression of RPL8 by qRT-PCR experiment. The Kaplan-Meier plotter, UALCAN, TCGAportal and HPA databases were applied to evaluate RPL8 on prognosis and clinicopathological parameters. Moreover, we used TIMER and Kaplan-Meier plotter to analyze the correlation of RPL8 to immune cell infiltration and immune cell type markers to prognosis. In addition, networks and function enrichment between RPL8 coexpression genes were analyzed by GeneMANIA, cBioportal and Metascape databases. What's more, we used FerrDb and GEPIA databases to analyze the correlation of 23 Ferroptosis-related genes with RPL8. RESULTS: The mRNA expression of RPL8 was over-expressed in multiple cancers. In addition, transcription and translation levels of RPL8 in LIHC were significantly higher than normal tissues. Furthermore, higher expression of RPL8 was closely related to shorter OS in LIHC patients. The analysis of Kaplan-Meier plotter proved that RPL8 expression was related to stage, Sorafenib treatment, alcohol consumption and hepatitis virus. Moreover, the results showed that the methylation expression level of RPL8 was significantly associated with age, gender, grade, stage and TP53 mutation of LIHC. RPL8 and its co-expression genes were primarily involved in liver regeneration and immune system process. Immune infiltration analysis showed the RPL8 expression had positively correlated with immune cells and immune subtypes in LIHC. Furthermore, qRT-PCR experiment validated the expression difference of RPL8 in liver cancer. CONCLUSION: Our findings elucidated that ferroptosis-markers RPL8 may play an important role in prognosis, and significantly correlate with ferroptosis-related genes, it also revealed the potential of RPL8 as a novel therapeutic target for LIHC treatment and prognosis assessment.

Nomogram based on spleen volume expansion rate predicts esophagogastric varices bleeding risk in patients with hepatitis B liver cirrhosis.

Background: We aimed to explore the risk factors for hemorrhage of esophagogastric varices (EGVs) in patients with hepatitis B cirrhosis and to construct a novel nomogram model based on the spleen volume expansion rate to predict the risk of esophagogastric varices bleeding. Methods: Univariate and multivariate logistic regression analysis was used to analyze the risk factors for EGVs bleeding. Nomograms were established based on the multivariate analysis results. The predictive accuracy of the nomograms was assessed using the area under the curve (AUC or C-index) of the receiver operating characteristic (ROC) and calibration curves. Decision curve analysis was used to determine the clinical benefit of the nomogram. We created a nomogram of the best predictive models. Results: A total of 142 patients' hepatitis B cirrhosis with esophagogastric varices were included in this study, of whom 85 (59.9%) had a history of EGVs bleeding and 57 (40.1%) had no EGVs bleeding. The spleen volume expansion rate, serum sodium levels (mmol/L), hemoglobin levels (g/L), and prothrombin time (s) were independent predictors for EGVs bleeding in patients with hepatitis B liver cirrhosis (P < 0.05). The above predictors were included in the nomogram prediction model. The area under the ROC curve (AUROC) of the nomogram was 0.781, the C-index obtained by internal validation was 0.757, and the calibration prediction curve fit well with the ideal curve. The AUROCs of the PLT-MELD and APRI were 0.648 and 0.548, respectively. Conclusion: In this study, a novel nomogram for predicting the risk of EGVs bleeding in patients with hepatitis B cirrhosis was successfully constructed by combining the spleen volume expansion rate, serum sodium levels, hemoglobin levels, and prothrombin time. The predictive model can provide clinicians with a reference to help them make clinical decisions.

Capecitabine Regulates HSP90AB1 Expression and Induces Apoptosis via Akt/SMARCC1/AP-1/ROS Axis in T Cells.

Transplant oncology is a newly emerging discipline integrating oncology, transplant medicine, and surgery and has brought malignancy treatment into a new era via transplantation. In this context, obtaining a drug with both immunosuppressive and antitumor effects can take into account the dual needs of preventing both transplant rejection and tumor recurrence in liver transplantation patients with malignancies. Capecitabine (CAP), a classic antitumor drug, has been shown to induce reactive oxygen species (ROS) production and apoptosis in tumor cells. Meanwhile, we have demonstrated that CAP can induce ROS production and apoptosis in T cells to exert immunosuppressive effects, but its underlying molecular mechanism is still unclear. In this study, metronomic doses of CAP were administered to normal mice by gavage, and the spleen was selected for quantitative proteomic and phosphoproteomic analysis. The results showed that CAP significantly reduced the expression of HSP90AB1 and SMARCC1 in the spleen. It was subsequently confirmed that CAP also significantly reduced the expression of HSP90AB1 and SMARCC1 and increased ROS and apoptosis levels in T cells. The results of in vitro experiments showed that HSP90AB1 knockdown resulted in a significant decrease in p-Akt, SMARCC1, p-c-Fos, and p-c-Jun expression levels and a significant increase in ROS and apoptosis levels. HSP90AB1 overexpression significantly inhibited CAP-induced T cell apoptosis by increasing the p-Akt, SMARCC1, p-c-Fos, and p-c-Jun expression levels and reducing the ROS level. In conclusion, HSP90AB1 is a key target of CAP-induced T cell apoptosis via Akt/SMARCC1/AP-1/ROS axis, which provides a novel understanding of CAP-induced T cell apoptosis and lays the experimental foundation for further exploring CAP as an immunosuppressant with antitumor effects to optimize the medication regimen for transplantation patients.

New insights into physicochemical properties of different particulate size-fractions and dissolved organic matter derived from biochars and their sorption capacity for phenanthrene.

To improve the knowledge of the heterogeneity and sorption behavior of biochars on hydrophobic organic contaminants (HOCs), pristine biochars (PBCs, 400 and 700 °C) were fractionated into four particulate fractions (SfBCs) and dissolved organic matter derived from biochars (DBC), then the sorption capacities of them towards phenanthrene were examined. Results showed that the OC-normalized sorption distribution coefficients (Koc) of PBCs were generally at intermediate levels among that of SfBCs and DBCs. The logKoc values of SfBCs increased as particle sizes decreased. By virtue of the higher micropore volume, specific surface area, aromaticity and hydrophobicity, the lowest SfBCs (0.45-10 µm, BC0.45-10) exhibited remarkably higher logKoc. Besides, although SfBCs from 700 °C generally showed larger logKoc than counterparts from 400 °C, almost no difference was observed for logKoc values of BC0.45-10 fractions from 400 and 700 °C. We thus speculated that particle size might have stronger effect on their sorption capacity than pyrolysis temperature. Although DBCs exhibited dramatically lower logKoc values than nano-scale SfBCs, they were interestingly comparable to large-sized SfBCs. Our findings thus suggested the importance of small particulate biochar species and DBCs on HOCs transport should be both highlighted since these fractions were highly dynamic in the environment.

Capecitabine Can Induce T Cell Apoptosis: A Potential Immunosuppressive Agent With Anti-Cancer Effect.

Capecitabine (CAP) is now widely used in the comprehensive treatment of digestive system tumors. Some clinical observations have shown that CAP may have immunosuppressive effects, but there is still a lack of clear experimental verification. In this study, different doses of CAP were administered to normal mice by gavage. Our results confirmed that CAP did not cause myelosuppression in bone marrow tissue; CAP selectively reduced the proportion of T cells and the concentration of related pro-inflammatory cytokines, while it increased the concentration of anti-inflammatory cytokines. Thymidylate phosphorylase (TP) is the key enzyme for the transformation of CAP in vivo; this study confirmed that T cells express TP, but the bone marrow tissue lacks TP expression, which explains the selectivity in pharmacodynamic effects of CAP. In addition, it was confirmed that CAP can induce T cell apoptosis in vivo and in vitro. In vitro experiments showed that CAP-induced T cell apoptosis was related to TP expression, endoplasmic reticulum stress (ERS) induction, reactive oxygen species (ROS) production, and mitochondria-mediated apoptosis activation. Therefore, this study confirmed that the differential expression of TP in cells and tissues explains why CAP avoids the toxic effects of myelosuppression while inducing T cell apoptosis to exert the immunosuppressive effect. Therefore, CAP may become an immunosuppressive agent with a simultaneous anti-cancer effect, which is worthy of further studies.

Applicability Analysis of Determination Models for Nanopores in Coal Using Low-Pressure CO2 and N2 Adsorption Methods.

The development characteristics of nanopores (with pore sizes <200 nm) in coal are a key factor affecting the accumulation and migration of coalbed methane (CBM). Thus, an appropriate determination method and calculation model are essential for accurate nanopore representation. Based on the experiments of low-pressure CO2 adsorption (LP-CO2GA) at 273 K and low-pressure N2 adsorption (LP-N2GA) at 77 K on four coals with different ranks, the abilities of different models (e.g., Langmuir, Dubinin-Radushkevich (D-R), Dubinin-Astakhov (D-A), Brunauer-Emmett-Teller (BET) and nonlocal density functional theory (NLDFT)) to accurately predict the pore parameters were analyzed. The results showed that (1) for LP-N2GA, the Langmuir model is only suitable for gas adsorptions at low relative pressure conditions (P/P0 < 0.01), and its error value increased with the relative adsorption pressure. The fitting results of the D-R model showed good agreement with the D-A model under low relative pressure of LP-CO2GA (P/P0 < 0.01), and the D-A model had more accurate fitting results. The BET model is more accurate than the other models (φ = -1.2733%) only in the interval of LP-N2GA with 0.05 < P/P0 < 0.35. The data also showed that the NLDFT model can maintain a higher fitting accuracy for LPCO2/N2GA processes at relative adsorption pressures from 0.001-0.9996. (2) Using LP-CO2GA with the Langmuir, D-R, D-A, and NLDFT models, the micropore specific surface area (SSA; 66.9570-248.6736 m²/g) and pore volume (0.0201- 0.0997 cm³/g) were obtained, while the values of meso-/macropore SSA (0.0007-2.3398 m²/g) and pore volume (0.0036-0.04 cm³/g) were calculated by LP-N2GA with the BET and NLDFT models. The results showed that the fitting accuracy in descending order was the D-R, D-A, Langmuir and NLDFT models. (3) In combination with the applicable model range, LP-CO2GA with the NLDFT model was recommended for micropore analysis of the coal pore sizes from 0.36-1.1 nm, while LP-N2GA combined with the NLDFT model was recommended for nanopore analysis of pore sizes from 1.1-200 nm. (4) The characteristics of pore development in the Beiloutian coal were analyzed using LP-CO2/N2GA combined with the NLDFT model. It was found that a pore volume and SSA less than 1.0 nm accounted for 88.82% of the total pore volume and 98.05% of the total SSA, indicating that micropores in coal are the main space for CBM storage and are key physical factors for the occurrence and migration of coalbed methane. The conclusions of this article will provide a basis for the accurate calculation of nanopores in coal.

Mono and co-immobilization of imidazolium ionic liquids on silica: effects of the substituted groups on the adsorption behavior of 2,4-dinitrophenol.

Ionic liquid modified silicas with high adsorption capacity for phenols prompt us to deeply explore the contribution of interactions between the adsorbent and adsorbate, with a particular focus on hydrophobicity, π-π, electrostatic and acid-base interactions. Herein, by introducing a series of typical substituent groups including N,N-dimethylaminopropyl (A), benzyl (B), dodecyl (D) and naphthylmethyl (N) in an imidazole ring (Im), three mono-immobilized and two co-immobilized imidazolium ionic liquid modified silicas, namely SilprAImCl, SilprBImCl, SilprNImCl, SilprDBImCl and SilprDAImCl, werre synthesized for removal and recovery of 2,4-dinitrophenol (2,4-DNP) from aqueous solutions. Adsorption kinetics, isotherms, thermodynamic analysis and desorption experiments have been carried out. The experimental results reveal that the substituent groups such as N,N-dimethylaminopropyl, benzyl and naphthylmethyl on the imidazole ring can significantly enhance the adsorption of 2,4-DNP via the acid-base interaction or π-π interaction and the adsorption capacity of 2,4-DNP follows the order: SilprNImCl > SilprAImCl > SilprBImCl. Furthermore, SilprDBImCl exhibits the largest adsorption capacity and SilprDAImCl has the lowest among the five adsorbents. These interesting finds indicate that the combination of hydrophobicity and π-π interactions lead to enhanced adsorption performance towards 2,4-DNP, while the combination of the hydrophobicity and acid-base interactions can restrain greatly adsorption of 2,4-DNP from aqueous medium. Adsorption mechanisms of 2,4-DNP on the five adsorbents have been clarified. These results will provide a deeper insight for efficient removal of phenols from water environments.

Flocculation-ultrasonic assisted extraction and solid phase clean-up for determination of polycyclic aromatic hydrocarbons in water rich in colloidal particulate with high performance liquid chromatography and ultraviolet-fluorescence detection.

In the present work, a simple method of sample preparation for the determination of polycyclic aromatic hydrocarbons (PAHs) in water rich in colloidal particulate was developed. The technique was mainly based on the effect of the flocculation of aluminum sulfate and the adsorption of the flocculation aid florisil. The method contained three steps: flocculation, ultrasonic extraction, and solid-phase extraction cleanup. Major parameters of the procedure were optimized with high performance liquid chromatography (HPLC) separation and ultraviolet-fluorescence detection. When 250 mL model sample containing 16 EPA PAHs was processed, the developed method provided detection limits in the range of 0.02-5 ng/L. Both spiked and non-spiked polluted river water samples rich in suspended particles and organic matters were analyzed. Recoveries and relative standard deviations for the 16 PAHs were in ranges of 86-94% and 3-13% (n=5), respectively.

Flow-injection analysis for the determination of total inorganic carbon and total organic carbon in water using the H2O2-luminol-uranine chemiluminescent reaction.

In the presence of carbonate and uranine, the chemiluminescent intensity from the reaction of luminol with hydrogen peroxide was dramatically enhanced in a basic medium. Based on this fact and coupled with the technique of flow-injection analysis, a highly sensitive method was developed for the determination of carbonate with a wide linear range. The method provided the determination of carbonate with a wide linear range of 1.0 x 10(-10)-5.0 x 10(-6) mol L(-1) and a low detection limit (S/N = 3) of carbonate of 1.2 x 10(-11) mol L(-1). The average relative standard deviation for 1.0 x 10(-9)-9.0 x 10(-7) mol L(-1) of carbonate was 3.7% (n = 11). Combined with the wet oxidation of potassium persulfate, the method was applied to the simultaneous determination of total inorganic carbon (TIC) and total organic carbon (TOC) in water. The linear ranges for TIC and TOC were 1.2 x 10(-6)-6.0 x 10(-2) mg L(-1) and 0.08-30 mg L(-1) carbon, respectively. Recoveries of 97.4-106.4% for TIC and 96.0-98.5% for TOC were obtained by adding 5 or 50 mg L(-1) of carbon to the water samples. The relative standard deviations (RSDs) were 2.6-4.8% for TIC and 4.6-6.6% for TOC (n = 5). The mechanism of the chemiluminescent reaction was also explored and a reasonable explanation about chemical energy transfer from luminol to uranine was proposed.

[Determination of dihydroxybenzenes using high performance liquid chromatography with acidic potassium permanganate chemiluminescence].

A sensitive, selective and simple post-column chemiluminescence (CL) detection method for simultaneously determining catechol, resorcinol, hydroquinone has been developed based on high performance liquid chromatography (HPLC) coupled with CL detection using reaction of dihydroxybenzenes with acidified potassium permanganate solution with the enhancing effect of formic acid. The optimal conditions for the CL detection and HPLC separation were achieved. Dihydroxybenzene isomers were baseline separated at column temperature of 25 degrees C using a mobile phase of methanol-0.1 mmol/L beta-cyclodextrin aqueous solution (30/70, v/v) with an isocratic elution program and the mobile phase matched well the CL detection. For all compounds, the linear ranges of the CL detection were about two orders of magnitude. The detection limits were 3.2 microg/L for hydroquinone, 4.7 microg/L for resorcinol and 5.2 microg/L for catechol. Combining with solid phase extraction, the proposed method was successfully applied to the determination of dihydroxybenzenes in river water. The recoveries for the three dihydroxybenzenes were 92.1%-95.4%.

Post-column detection of benzenediols and 1,2,4-benzenetriol based on acidic potassium permanganate chemiluminescence.

Based on the sensitizing effect of formic acid on the chemiluminescence (CL) reaction of polyhydroxylbenzenes with acidified potassium permanganate and the combination technique of high-performance liquid chromatography (HPLC), a sensitive, selective and simple post-column CL detection method for simultaneously determining catechol, resorcinol, hydroquinone and 1,2,4-benzenetriol is described. The optimal conditions for the CL detection and HPLC separation were carried out. The linear ranges were: 6.0 x 10(-3)-1.5 mg/L for hydroquinone, 8.0 x 10(-3)-1.5 mg/L for 1,2,4-benzenetriol, 1.0 x 10(-2)-2.0 mg/L for resorcinol and 1.0 x 10(-2)-2.5 mg/L for catechol, respectively. The detection limits are: 3.2 x 10(-3) mg/L for hydroquinone, 3.9 x 10(-3) mg/L for 1,2,4-benzenetriol, 4.7 x 10(-3) mg/L for resorcinol and 5.2 x 10(-3) mg/L for catechol, respectively. Combining with solid phase extraction, the proposed method has been successfully applied to the determination of the polyhydroxylbenzenes in river water. The recoveries for three benzentriols were 92.1-95.4% and 82.0% for 1,2,4-benzenetriol, respectively.