Novel Silver Complexes Based on Phosphanes and Ester Derivatives of Bis(pyrazol-1-yl)acetate Ligands Targeting TrxR: New Promising Chemotherapeutic Tools Relevant to SCLC Management.

Bis(pyrazol-1-yl)acetic acid (HC(pz)2COOH) and bis(3,5-dimethyl-pyrazol-1-yl)acetic acid (HC(pzMe2)2COOH) were converted into the methyl ester derivatives 1 (LOMe) and 2 (L2OMe), respectively, and were used for the preparation of silver(I) complexes 3-5. The Ag(I) complexes were prepared by the reaction of AgNO3 and 1,3,5-triaza-7-phosphaadamantane (PTA) or triphenylphosphine (PPh3) with LOMe and L2OMe in methanol solution. All Ag(I) complexes showed a significant in vitro antitumor activity, proving to be more effective than the reference drug cisplatin in the in-house human cancer cell line panel containing examples of different solid tumors. Compounds were particularly effective against the highly aggressive and intrinsically resistant human small-cell lung carcinoma (SCLC) cells, either in 2D and 3D cancer cell models. Mechanistic studies revealed their ability to accumulate into cancer cells and to selectively target Thioredoxin (TrxR), thus leading to redox homeostasis unbalance and ultimately inducing cancer cell death through apoptosis.

Analysis of Monacolins and Berberine in Food Supplements for Lipid Control: An Overview of Products Sold on the Italian Market.

The use of dietary supplements for the prevention and management of diseases associated with excess of lipids is spreading in Western countries. Supplements containing red yeast rice (RYR) and extracts from Berberis species, characterized, respectively, by the active compounds monacolin K (MK) and berberine (BBR), are sold in pharmacies as over the counter medicines (OTC) and in regular markets without the need of medical prescription and medical surveillance. However, MK is chemically identical to lovastatin, a drug commonly used to treat hypercholesterolemia, and is characterized by the same mechanism of action, pharmacokinetic profile and toxicity. On the other hand, although BBR-containing supplements are considered to be well-tolerated and safe, they frequently show poor standardization of active ingredients, and this could lead to lack of effects. In this work, with the aim to give an overview on the potency of RYR- and BBR-containing supplements available on the Italian market, we analyzed a pool of supplements bought from both local pharmacies and markets. Results confirm the data already published by other authors, showing scarce standardization of bioactives and discrepancy between the doses of bioactives reported by the manufacturers and the amounts resulting from analysis of the same products. Overall, our data represent a further proof that a strict legislation regulating the production and marketing of dietary supplements and a close monitoring of these products by food and drug regulatory organs is mandatory.

Antiproliferative Homoleptic and Heteroleptic Phosphino Silver(I) Complexes: Effect of Ligand Combination on Their Biological Mechanism of Action.

A series of neutral mixed-ligand [HB(pz)3]Ag(PR3) silver(I) complexes (PR3 = tertiary phosphine, [HB(pz)3]- = tris(pyrazolyl)borate anion), and the corresponding homoleptic [Ag(PR3)4]BF4 compounds have been synthesized and fully characterized. Silver compounds were screened for their antiproliferative activities against a wide panel of human cancer cells derived from solid tumors and endowed with different platinum drug sensitivity. Mixed-ligand complexes were generally more effective than the corresponding homoleptic derivatives, but the most active compounds were [HB(pz)3]Ag(PPh3) (5) and [Ag(PPh3)4]BF4 (10), both comprising the lipophilic PPh3 phosphine ligand. Detailed mechanistic studies revealed that both homoleptic and heteroleptic silver complexes strongly and selectively inhibit the selenoenzyme thioredoxin reductase both as isolated enzyme and in human ovarian cancer cells (half inhibition concentration values in the nanomolar range) causing the disruption of cellular thiol-redox homeostasis, and leading to apoptotic cell death. Moreover, for heteroleptic Ag(I) derivatives, an additional ability to damage nuclear DNA has been detected. These results confirm the importance of the type of silver ion coordinating ligands in affecting the biological behavior of the overall corresponding silver complexes, besides in terms of hydrophilic-lipophilic balance, also in terms of biological mechanism of action, such as interaction with DNA and/or thioredoxin reductase.

Kinetics of Linezolid in Continuous Renal Replacement Therapy: An In Vitro Study.

BACKGROUND: Continuous veno-venous hemofiltration (CVVH) could affect the pharmacokinetic profile of linezolid (LZD). The aim of this study was to evaluate the LZD extracorporeal clearance using an in vitro CVVH model. METHODS: A sham miniaturized CVVH circuit (CARPEDIEM; Bellco, Mirandola, Italy) was set up with a polysulfone hemofilter (0.25 m; cutoff 50,000 Da) for 240 minutes using normal saline solution (0.9% wt/vol NaCl) and blood (n = 6) spiked with LZD. Drug solution samples were collected during CVVH at 10, 30, 60, 120, and 240 minutes. LZD levels were measured by high-performance liquid chromatography. RESULTS: Results were used to estimate pharmacokinetic parameters. The LZD baseline level decreased from 17.24 ± 0.54 to 9.73 ± 4.85 mg/L and from 11.75 ± 0.08 to 5.01 ± 0.67 mg/L in the first 10 minutes, and then increased to 13.2 ± 3.10 and 7.4 ± 0.71 mg/L in normal saline solution and blood, respectively. Mass balance analysis reported a rapid adsorption of LZD onto a polysulfone membrane followed by its release: a rebound phenomenon occurred. CONCLUSIONS: Although further studies are necessary to clarify this phenomenon, LZD level variations observed in our study should be considered to avoid antimicrobial underexposure. Several strategies are available for adjusting the dosage regimen of LZD, but therapeutic drug monitoring is highly recommended when it is used.

The protein profile of Theobroma cacao L. seeds as obtained by matrix-assisted laser desorption/ionization mass spectrometry.

The water-soluble protein profile of the seeds of green, red, and yellow Theobroma cacao L. fruits has been determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF-MS). The seeds were powdered under liquid nitrogen and defatted. The residues were dialyzed and lyophilized. The obtained samples were suspended in the matrix solution of sinapinic acid. The obtained MALDI mass spectra showed the presence of a wide number of proteins with molecular weight ranging from 8000 to 13,000 Da and a cluster of peaks centered at 21,000 Da that were attributed to albumin. The abundance of this peak was found to depend on the different portion of the seed (husk, apical and cortical parts); however, the MALDI mass spectra obtained from the different varieties of cocoa were practically superimposable. Changes in the protein profiles were also observed after the cocoa seeds were treated by fermentation and roasting, which are processes usually employed for the commercial production of cocoa.

Pharmacokinetic analysis of antibiotic adsorption (vancomycin and teicoplanin) by the Lixelle extracorporeal unit.

PURPOSE: The pharmacokinetic properties of vancomycin (VAN) and teicoplanin (TEC) may be affected by adsorption during hemofiltration as well as hemoperfusion therapies. The aim of this in vitro study was to investigate VAN and TEC removal adsorption kinetics with mass balance analysis by direct hemoperfusion (DHP) with the Lixelle S-35 cartridge (Lixelle, Kaneka Corporation, Tokyo). METHODS: Mock DHP was performed for 120 min using VAN and TEC solutions (46.08 ± 0.81 and 74.79 ± 1.24 mg/l per N = 6). Clinical plasma antibiotic concentrations were circulated in a closed circuit simulating DHP using an adsorption column (Lixelle S-35) at flow rate of 250 ml/min. Samples were collected at 10, 60, and 120 min through both arterial and venous ports; drug levels were measured with particle enhanced turbidimetric inhibition immunoassay and fluorescence polarization immunoassay. All tests were performed in triplicate. RESULTS: Results subsequent to DHP at the primary assessment interval for VAN mass was 49.06 ± 1.47 mg, indicating a significant reduction of the starting mass (94.74 ± 1.63 mg). The observed reduction of TEC levels greatly exceeded that of VAN at the first interval (10 min). At 120 min of DHP, the estimated mass adsorption of VAN was 45.68 ± 2.26 mg, while the mesured total TEC mass adsorbed was 126.86 ± 0.91 mg. CONCLUSIONS: A VAN adsorption plateau indicating the VAN loading dose may be required in patients receiving DHP with the Lixelle S-35. The total TEC mass was adsorbed subsequent to 60 min of circulation, so the loading dose should be closely considered. In addition, the Lixelle S-35 may represent an option as a rescue therapy in accidental overdose of TEC.

New option for the treatment of hyperbilirubinemia: in vitro direct hemoperfusion with the Lixelle S-35.

PURPOSE: Limited options are available to treat critically ill patients with acute liver failure (ALF) and acute-on-chronic liver failure (AoCLF), therefore we set up an in vitro study in order to test the bilirubin adsorption capacity of the Lixelle S-35 cartridge by direct hemoperfusion (DHP). METHODS: Mock DHP was performed for 120 min using hyperbilirubinic human plasma and blood obtained from a plasmapheresis and exchange transfusion, respectively. The total bilirubin (TBIL) and direct bilirubin (DBIL) baseline concentrations were 17.57 ± 0.53, 12.57 ± 0.23 mg/dl for plasma and 23.10 ± 0.47, 15.37 ± 0.24 mg/dl for blood. Plasma and blood were separately circulated in a closed circuit simulating DHP using an adsorption column (Lixelle S-35) at flow rate of 100 ml/min. TBIL and DBIL levels were measured at 10, 30, 60, and 120 min from arterial and venous ports and assessed with the Jendrassik-Grof method. All tests were performed in triplicate. RESULTS: The total removal subsequent to DHP (120 min) was seen as TBIL in plasma 55.60%, TBIL in blood 62.16%, DBIL plasma 58.87%, DBIL in blood 64.41%, respectively. The estimated mass adsorption of TBIL in plasma 958.20 ± 5.72 mg, TBIL in blood 1233.60 ± 10.22 mg, DBIL in plasma 680.70 ± 10.68, DBIL in blood 818.10 ± 4.68, respectively. CONCLUSIONS: The bilirubin adsorption rates after DHP were very promising for both hyperbilirubinic plasma and blood. Although further in vitro investigations are required, including comparisons with other techniques, these findings have shown that the Lexille S-35 should represent an option for the management of hyperbilirubinemia in ALF or AoCLF.

Clarifying the identity of the main ellagitannin in the fruit of the strawberry, Fragaria vesca and Fragaria ananassa Duch.

Although the composition of strawberry fruit has been extensively studied, especially for the most abundant phenolic compounds, agrimoniin has never been univocally identified as one of the most abundant phenolic compounds in the fruit. In this study agrimoniin was isolated in the fruit of Fragaria vesca and its structure characterized. Furthermore, its presence was definitively established to be the main ellagitannin in both F. vesca and Fragaria ananassa D. fruit. The presence of sanguiin H-6 and lambertianin C as minor compounds was confirmed in both F. vesca and F. ananassa D. samples. For the first time here is reported the full NMR assignments for agrimoniin. These data should represent a point of reference for NMR analysis of this and other structurally related ellagitannins. Finally, the establishment of an HPLC protocol for separation provided information making it possible to avoid confusion with sanguiin H-6, the main ellagitannin in Rubus species, which is also present in strawberries but at a much lower concentration.