Pharmacologie du méthotrexate

An In Vitro Study of the Effects of Methotrexate Loaded Biocomposite Beads on MG63 Osteoblast Cells

This study aims to synthesize a new localized drug delivery system of bioglass, polyvinyl alcohol (PVA), cellulose (CNC), and sodium alginate (SA) beads as a carrier for methotrexate (MTX) drugs for the treatment of osteosarcoma. Methotrexate /Bioglass-loaded Polyvinyl/Cellulose/Sodium alginate biocomposite beads were prepared via the dropwise method with different concentrations of (65%SiO2-30%CaO- 5%P2O5) bioglass. Samples were named B0, S0, S1, S2, and S3, respectively. Calcium chloride (CaCl2) was used as a cross-linking agent. The obtained biocomposite beads were investigated by different techniques FTIR, XRD, SEM, etc. The bioactivity of MTX/BG-loaded PVA-CNC-SA biocomposite beads was tested by immersion in simulated body fluid (SBF). The profile release of methotrexate was investigated with UV-vis spectroscopy for 30 days. A cytotoxicity study of the methotrexate was performed by a human osteosarcoma (MG-63) cell line. Results indicated that the formation of a hydroxyapatite layer on the bead's surface confirmed its biological activity. Bioactivity was directly proportional to the BG content. All samples of B1, S0, S1, S2, and S3 exhibited significant maximum release up to 6 days and were controlled gradually. Cytotoxicity results of biocomposite beads showed that high cell death was detected on the MG-63 cells, with (IC-50 ± SD) of S3 (116.16 ± 1.57) compared with B1 (306.99 ± 2.72) and S1 (204.74 ± 4.55) due to the high release of MTX, which was confirmed by the results of the drug release profile. Results prove that the prepared biocomposite beads can be used as bioactive, drug delivery systems, and anticancer materials.

[Radiotherapy and immune suppression: A short review]

The management of patients undergoing immunosuppressive agents is really challenging. Based on precaution principle, it seems mandatory to stop immunosuppressive (or immunomodulating) agents during radiation. Yet, it is impossible in grafted patients. It is possible in patients with autoimmune disease, but in this case, the autoimmune disease might modify patient's radio-sensitivity. We provide a short review about the safety of radiotherapy in grafted/auto-immune patients. The literature is limited with data coming from outdated case-report or case-control studies. It seems that radiotherapy is feasible in grafted patients, but special dose-constraints limitations must probably be considered for the transplant and the other organs at risk. There is very little data about the safety of radiotherapy, when associated with immunomodulating agents. The most studied drug is the methotrexate but only its prescription as a chemotherapy (high doses for a short period of time) was reported. When used as an immunomodulator, it should probably be stopped 4 months before and after radiation. Apart from rheumatoid arthritis, it seems that collagen vascular diseases and especially systemic scleroderma and systemic lupus erythematous feature increased radio-sensitivity with increased severe late toxicities. Transplanted patients and collagen vascular disease patients should be informed that there is very little data about safety of radiation in their case.

Complexation of methotrexate via ligand diffusion molecular dynamic simulations under neutral, basic, and acidic conditions

Methotrexate (MTX), an FDA-approved drug employed in the treatment of several types of cancer and autoimmune diseases, is characterized by its poor solubility. Therefore, new strategies have been implemented such as coupling to nanocarriers to increase its solubility. Previous experimental studies have demonstrated complexation of MTX to polyamidoamine of a generation four (PAMAM-G4) dendrimer with a complex stoichiometry of 19/22:1 under neutral conditions, providing important information that can be used to further elucidate the structural and energetic basis of the molecular binding of MTX and PAMAM-G4. In this study, we performed ligand diffusion molecular dynamic simulations (LDMDSs), using 3 μs combined with the molecular mechanics generalized surface area (MMGBSA) approach employing saturating concentrations of MTX to explore the mechanism through which MTX is complexed by PAMAM-G4 at neutral, basic, and acidic conditions. Our results reproduce the reported complex stoichiometry between MTX and PAMAM-G4 in neutral conditions. Binding free energy values suggest a much slower release in neutral and acidic conditions, consistent with the controlled rate of drug release into the bloodstream and when reaching the acidic environment of tumor tissues. Altogether, the methodology employed and the results may be useful in the evaluation of other drugs of pharmaceutical interest.

Preparation and characterization of folic acid functionalized bioactive glass for targeted delivery and sustained release of methotrexate

We have successfully prepared a novel targeted drug delivery system, composed of folic acid (FA) as targeting molecule, methotrexate (MTX) as anticancer drug, and bioactive glass (BG) as carrier. The BG nanoparticles were synthesized by sol-gel method with the dodecylamine as template. The surface of BG nanoparticles was grafted with amino groups by (3-aminopropyl) triethoxysilane, then, FA and MTX were covalently conjugated to the surface of modified BG through amidation reaction, so FA functionalized BG (BG-FA) and targeted drug delivery system (MTX-BG-FA) were prepared. The physicochemical properties of BG, BG-NH₂ , and BG-FA were characterized by various methods, such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, ultraviolet-visible, and so on. Moreover, the drug release results showed that the MTX-BG-FA had sustained release property because of the peptide bond between MTX and BG-FA. And the cytocompatibility evaluation demonstrated that the BG and BG-FA were biocompatible and BG-FA even could promote cell proliferation, while the MTX-BG-FA had high cytotoxicity owning to the sustained release of anticancer drug. From the above, it could be concluded that MTX-BG-FA could kill tumor cells targetedly and sustainedly, which made it a good cancer targeted therapy material. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 319-329, 2019.

Risk of Adverse Pregnancy Outcome After Paternal Exposure to Methotrexate Within 90 Days Before Pregnancy

OBJECTIVE

To study the association between paternal exposure to methotrexate within the 90-day period before pregnancy and congenital malformations and stillbirth in the offspring.

METHODS

We conducted a nationwide register study. Our cohort consisted of all live births in Denmark between 1997 and 2011 identified from the Medical Birth Registry. Methotrexate-exposed fathers were identified from the National Prescription Registry. From the national Hospital Registry we identified paternity, live births, and stillbirths as well as discharge diagnoses on congenital malformations.

RESULTS

We identified 849,676 live births with known paternity. There were 127 live births of methotrexate-exposed fathers. Of these, four (3.2%) had major malformations compared with 28,814 (3.4%) of the unexposed. The odds ratio (OR) for major congenital malformation among exposed fathers compared with unexposed was 0.93 (95% confidence interval [CI] 0.34-2.51) and when adjusted for year of birth, maternal age, educational length, household income, and parity, the adjusted OR was 1.01 (95% CI 0.37-2.74). There were no stillbirths in the methotrexate-exposed group compared with 2,541 (0.3%) in the unexposed group and no increased risk of preterm birth (adjusted OR 1.31, 95% CI 0.66-2.59) among the children from exposed fathers.

CONCLUSION

We found no association between paternal exposure to methotrexate within 90 days before pregnancy and congenital malformations, stillbirths, or preterm birth. Available data suggest that prepregnancy paternal methotrexate exposure should not be of major concern. Multinational recommendations should be changed accordingly.

Methotrexate induces DNA damage and inhibits homologous recombination repair in choriocarcinoma cells

OBJECTIVE

The objective of this study was to investigate the mechanism of sensitivity to methotrexate (MTX) in human choriocarcinoma cells regarding DNA damage response.

METHODS

Two choriocarcinoma cancer cell lines, JAR and JEG-3, were utilized in this study. An MTX-sensitive osteosarcoma cell line MG63, an MTX-resistant epithelial ovarian cancer cell line A2780 and an MTX-resistant cervical adenocarcinoma cell line Hela served as controls. Cell viability assay was carried out to assess MTX sensitivity of cell lines. MTX-induced DNA damage was evaluated by comet assay. Quantitative reverse transcription polymerase chain reaction was used to detect the mRNA levels of BRCA1, BRCA2, RAD51 and RAD52. The protein levels of γH2AX, RAD 51 and p53 were analyzed by Western blot.

RESULTS

Remarkable DNA strand breaks were observed in MTX-sensitive cell lines (JAR, JEG-3 and MG63) but not in MTX-resistant cancer cells (A2780 and Hela) after 48 h of MTX treatment. Only in the choriocarcinoma cells, the expression of homologous recombination (HR) repair gene RAD51 was dramatically suppressed by MTX in a dose- and time-dependent manner, accompanied with the increase in p53.

CONCLUSION

The MTX-induced DNA strand breaks accompanied by deficiencies in HR repair may contribute to the hypersensitivity to chemotherapy in choriocarcinoma.

The Impact of Resveratrol on Oxidative Stress Induced by Methotrexate in Rat Ileum Tissue: Evaluation of Biochemical and Histopathological Features and Analysis of Gene Expression

OBJECTIVE

The aim of this study was to assess the impact of resveratrol (RST) on oxidative stress induced by methotrexate in rat ileum tissue.

MATERIALS AND METHODS

Twenty-four rats were divided into 4 groups with 6 in each group. Each rat was orally administered the following every day for 30 days: group 1 (MTXG), methotrexate (MTX; 5 mg/kg); group 2 (RMTXG), MTX (5 mg/kg) plus RST (25 mg/kg/day); group 3 (RSTG), RST alone (25 mg/kg/day), and group 4 (controls), distilled water. After the rats had been sacrified, the ilea were removed for the assessment of malondialdehyde (MDA), total glutathione (tGSH) and glutathione peroxidase (GSH-Px). Gene expression analyses for interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and myeloperoxidase (MPO) were also performed. Hematoxylin and eosin-stained paraffin-embedded sections of the ileum were analyzed under a light microscope and the findings were recorded. Statistical analyses of the data were performed using one-way ANOVA.

RESULTS

The administration of MTX in group 1 yielded a higher level of MDA (8.33 ± 2.5 μmol/g protein, p < 0.001) and lower levels of tGSH (0.97 ± 0.29 nmol/g protein) and GSH-Px (5.22 ± 0.35 U/g protein, p < 0.001) compared to the other groups. MTX also increased IL-1β (40.33 ± 5.43 gene expression levels), TNF-α (6.08 ± 0.59) and MPO gene expression (9 ± 1.41) in group 1 compared to the controls (11.33 ± 2.07, 2.15 ± 0.33 and 3.43 ± 0.48, respectively, p < 0.001). The impact of RST on IL-1β, TNF-α and MPO gene expression induced by MTX was observed as a reversal of these findings (p < 0.05). Severe inflammation, damage to the villus epithelium and crypt necrosis was observed histopathologically in the MTXG group, whereas only mild inflammation was seen in the RMTXG group.

CONCLUSION

In this study, ileal damage caused by MTX was inhibited by RST.