Piotr Wroczyński

Comparison of antioxidant enzymes activity and the concentration of uric acid in the saliva of patients with oral cavity cancer, odontogenic cysts and healthy subjects.

Chronic inflammation is related to oxidative stress and is still believed to be the cause of carcinogenesis. Patients with oral cavity cancer (OCC) exhibited lower total antioxidant capacity, uric acid (UA) concentration, salivary peroxidise (SPO) and superoxide dismutase (SOD) activity in their saliva than did healthy subjects. This could be a risk factor for tumour induction. Odontogenic cysts also arise in response to locally acting proinflammatory factors, for example, a gangrenous tooth. Furthermore, cyst development is accompanied by chronic inflammation. There are some reports in the literature concerning primary tumours such as squamous cell carcinomas arising from odontogenic cysts. The reason for this transformation is still unknown. The aim of this study was to compare the status of the antioxidant defence system in the saliva of the group with odontogenic cysts and OCC with that of the healthy control. Saliva samples were collected in the morning. SOD, SPO activity and UA concentration were determined using standard methods. Patients with odontogenic cysts and OCC exhibited lower activity of major antioxidants in their saliva (SPO, UA) than did healthy people. SOD activity and age are the main factors that distinguish these diseases. Discriminant function analysis showed that once data such as antioxidant status of saliva, age and smoking status are known 80% cases can be correctly classified as healthy, 80% as having odontogenic cysts and 40% as cancerous. To conclude, the decrease in concentrations of major antioxidants in the saliva of patients with cysts may increase the risk of neoplastic transformation especially in advanced age.

Salivary Aldehyde Dehydrogenase: Activity towards Aromatic Aldehydes and Comparison with Recombinant ALDH3A1

A series of aromatic aldehydes was examined as substrates for salivary aldehyde dehydrogenase (sALDH) and the recombinant ALDH3A1. Para-substituted benzaldehydes, cinnamic aldehyde and 2-naphthaldehydes were found to be excellent substrates, and kinetic parameters for both salivary and recombinant ALDH were nearly identical. It was demonstrated that for the fluorogenic naphthaldehydes the only produced reaction product after incubation in saliva is the carboxylate.

Aromatic aldehydes as fluorogenic indicators for human aldehyde dehydrogenases and oxidases: substrate and isozyme specificity

Substrate properties of a number of potentially fluorogenic aromatic aldehydes of naphthalenes, phenanthrenes and anthracenes and of some coumarin aldehydes towards various forms of the human and rat aldehyde oxidase and dehydrogenase were examined using absorption and emission spectroscopy. It was demonstrated that recombinant human class 1 aldehyde dehydrogenase (ALDH-1) readily oxidizes naphthalene (except for those ortho-substituted), phenanthrene and coumarin aldehydes, whereas the class 3 enzyme (ALDH-3) from human saliva is active only towards 2-naphthaldehyde derivatives. The observed reaction rates in both cases are comparable to those of the best known substrates, and the Km values are typically in the sub-micromolar range. Aldehyde oxidases (AlOx), which are present in mammalian liver, reveal much broader substrate specificity, oxidizing nearly all the compounds examined, including those of the anthracene series, with maximum activity in the micromolar range of substrate concentration. In rat liver, nearly all AlOx activity was located in the cytosolic fraction.

Selenium in the Therapy of Neurological Diseases. Where is it Going

Selenium (34Se), an antioxidant trace element, is an important regulator of brain function. These beneficial properties that Se possesses are attributed to its ability to be incorporated into selenoproteins as an amino acid. Several selenoproteins are expressed in the brain, in which some of them, e.g. glutathione peroxidases (GPxs), thioredoxin reductases (TrxRs) or selenoprotein P (SelP), are strongly involved in antioxidant defence and in maintaining intercellular reducing conditions. Since increased oxidative stress has been implicated in neurological disorders, including Parkinson’s disease, Alzheimer’s disease, stroke, epilepsy and others, a growing body of evidence suggests that Se depletion followed by decreased activity of Se-dependent enzymes may be important factors connected with those pathologies. Undoubtedly, the remarkable progress that has been made in understanding the biological function of Se in the brain has opened up new potential possibilities for the treatment of neurological diseases by using Se as a potential drug. However, further research in the search for optimal Se donors is necessary in order to achieve an effective and safe therapeutic income.

Cloud-point extraction is compatible with liquid chromatography coupled to electrospray ionization mass spectrometry for the determination of bisoprolol in human plasma

Cloud-point extraction (CPE) draws increasing interest in a number of analytical fields including bioanalysis, but combining CPE and LC-MS with electrospray ionization (ESI) in the determination of drugs in biological fluids such as plasma, serum or blood has not been reported so far. Bisoprolol was determined in human plasma by CPE using Trition X-114 as a surfactant and metoprolol as the internal standard. NaOH concentration, temperature and Trition X-114 concentration were optimized. All analyses were performed using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). All validation experiments met international acceptance criteria and no significant matrix effect was observed. The compatibility of CPE and LC-ESI-MS/MS was confirmed using clinical plasma samples and appropriate statistical tests. The determination of bisoprolol concentration in human plasma in the range 1.0-70ngmL(-1) by the CPE method leads to the results which are equivalent to those obtained by the widely used liquid-liquid extraction method. The results revealed that a structural analogue may be an appropriate internal standard when CPE is used as the extraction technique. CPE offers significant practical advantages over the classical extraction methods, including a positive impact on the environment, therefore its wider application in future pharmacokinetic studies is justifiable.

Application of a novel liquid chromatography/tandem mass spectrometry method for the determination of antazoline in human plasma: Result of ELEPHANT-I [ELEctrophysiological, pharmacokinetic and hemodynamic effects of PHenazolinum (ANTazoline mesylate)] human pharmacokinetic study.

Antazoline is a first-generation antihistaminic agent with antiarrhythmic quinidine-like properties. In some countries, it is widely used for termination of cardiac arrhythmias, especially atrial fibrillation (AF). However, no human pharmacokinetic studies have been conducted with intravenous antazoline. The aim of our study was to develop and validate a novel liquid chromatography/tandem mass spectrometry (LC-MS/MS) method for the determination of antazoline in human plasma: the ELEPHANT-I [ELEctrophysiological, pharmacokinetic and hemodynamic effects of PHenazolinum (ANTazoline mesylate)] human pharmacokinetic study. Antazoline was extracted from plasma using liquid-liquid extraction. The concentration of the analyte was measured by LC-MS/MS with xylometazoline as an internal standard. The method was validated for linearity, precision, accuracy, stability (freeze/thaw stability, stability in autosampler, short and long term stability), dilution integrity and matrix effect. The analyzed validation criteria were fulfilled. The method was applied to a pharmacokinetic study involving 10 healthy volunteers. Following a single intravenous dose of antazoline mesylate (100 mg), the plasma concentration profile showed a relative fast elimination with a terminal elimination half-life of 2.29 h. A relatively high volume of distribution was observed (Vss=315 L). The values of mean residence time (MRT∞), area under the curve (AUC∞) and clearance were 3.45 h, 0.91 mg h L(-1) and 80.5 L h(-1), respectively. One volunteer showed significant differences in pharmacokinetic parameters. In conclusion, the proposed new LC-MS/MS method was successfully used for the first time for the determination of antazoline in human plasma.

Determination of selected cardiovascular active compounds in environmental aquatic samples--Methods and results, a review of global publications from the last 10 years.

In recent years cardiovascular diseases were the second most common cause of death worldwide. Therefore, the consumption of cardiovascular drugs is high, which might result in an increase of them in the environment. The major source of aquatic environmental contamination is still effluents of wastewater treatment plants (WWTPs). Unfortunately removal of cardiovascular active compounds and/or their metabolites in WWTP is still unsatisfactory. Among microbial and abiotic degradation of these compounds during wastewater processes, photolysis and photodegradation of cardiovascular drugs also play an important role. New formed compounds may be more toxic or retain the properties of parent compounds. Thus the main goal of this paper was to provide a detailed and comprehensive review of used analytical methods, coupled to liquid chromatography-tandem mass spectrometry, to determine the presence of cardiovascular compounds in surface waters as well as WTTPs effluents and influents. Exhaustive preparation for mass spectrometry detection and quantitation including samples pre-treatment, and the common problem of the matrix effect are thoroughly explored in this paper. Additionally, the article provides some hints in respect of recently noted problematic issue related to the availability of specific standards for the analysis of drugs metabolites. Furthermore, information concerning the metabolism of cardiovascular active compounds including differences in metabolism within enantiomers is described. This article also touches on the problems associated with environmental risk assessment due to the presence of cardiovasculars in the environment. The paper also tries to explain differences in concentrations among cardiovascular compounds between countries worldwide.

Continuous fluorimetric assay for human aldehyde dehydrogenase and its application to blood analysis

Abstract A highly fluorogenic synthetic substrate for human “low K m ” aldehyde dehydrogenase (ALDH) isozymes, 7-methoxy-1-naphthaldehyde, was identified. The new substrate is characterized by submicromolar or low micromolar Michaelis constants ( K m ) for both cytosolic and mitochondrial ALDH from the human liver. The cytosolic ALDH oxidizes the naphthaldehyde substrate with a rate almost equal to that of the respective acetaldehyde reaction, while the mitochondrial isozyme is ca. 25 fold less active. Thanks to a high fluorescence yield of the oxidation product, i.e., the corresponding naphthoate ( φ = 0.41), reaction rates as low as 0.1 nM min −1 can be measured reproducibly. The emission spectral characteristics of the naphthoate product differ significantly from that of the aldehyde (λ max at 395 and 475 nm, respectively), allowing a selective observation of the former, and there is also marked difference between the naphthoate and the corresponding alcohol (λ max at 355 nm), helping to eliminate possible interferences from alcohol dehydrogenase and/or aldehyde reductase in the fluorimetric assay. As a possible application of the new assay, it is shown that the ALDH activity can easily be detected, by continuous monitoring of the fluorescence increase, in 1000-fold diluted hemolysates, using 7-methoxy-1-naphthaldehyde and NAD + as substrates, and there is no necessity for prior removal of hemoglobin. Normal ALDH level in the blood of healthy volunteers has been measured, and the result, 4.9 U l −1 ( n = 27), agrees with the literature data obtained for the acetaldehyde oxidation activity, and exceeds by more than 20-fold the lower detection limit of the method. The present method is free of a background drift, characteristic of all the previously proposed spectral assays for ALDH.

Selenitetriglycerides—Redox-active agents

BACKGROUND Human prostate cancer (hPCa) is the most commonly diagnosed cancer in elderly men and is the second leading cause of male cancer death. Data from epidemiological, eco-environmental, nutritional prevention and clinical trials suggest that selenium Se(IV) can prevent prostate cancer. Selol, a new organic semisynthetic derivative of Se(IV), is a mixture of selenitetriglycerides. This mixture is non-toxic and non-mutagenic, and after po treatment - 56-times less toxic (in mice) than sodium selenite. It exhibits strong anti-cancer activity in vitro in many cancer cell lines and can overcome the cell resistance to doxorubicin. Selol seems a promising compound for prostate cancer therapy. MATERIALS AND METHODS The aim of the present study is the evaluation of Selols influence on intracellular redox state (Eh) of prostatic tumors and the liver in androgen-dependent hPCa-bearing mice, and extracellular redox state in serum of these mice. RESULTS AND CONCLUSIONS The anticancer activity of Selol involves perturbation of the redox regulation in the androgen dependent hPCa (LNCaP) cells, but not in healthy cells. After Selol treatment, intracellular Eh has increased in tumors from -223 mV to -175 mV, while in serum it has decreased (-82 mV vs -113 mV). It shows significant changes Eh in the extra- and intracellular environment. The difference decreases from 141 mV to 62 mV. The changes suggest that a tumor cell was probably directed toward apoptosis. This is exemplified in a significant decrease in cancer tumor mass by approx. 17% after the three weeks of Selol administration.

The development of the LC-MS/MS method based on S-9 biotransformation for detection of metabolites of selected β-adrenolytics in surface water.

Pharmaceuticals consumption in Poland is high. One of the most frequently prescribed is cardiovascular drugs. Due to their relatively high hydrophilic properties, they are not completely eliminated during wastewater treatment processes. In contrast to parent compounds, the presence of cardiovascular metabolites is rarely investigated in surface waters. The goal of this paper was to develop the methodology for detection of metabolites of selected beta-blockers: metoprolol, bisoprolol and propranolol. These metabolites were obtained by the incubation of parent compounds with S9 rats liver fraction and used for the development and optimization of the low resolution LC-MS/MS method. Accurate mass spectrometry measurements were applied for validation of this method. The incubation of the parent compound with S9 fraction resulted only in propranolols metabolites generation. However, on the basis of hydroxypropranolol, theoretically transitions for mono- and dihydroxy-metoprolol and bisoprolol derivatives were generated for MRM mode and applied for surface water analysis. The analysis revealed the presence of some of the target metabolites in the Vistula river. This work is the first one proposing the application of biotrasformation in the methodology of low resolution LC-MS-MS analysis of metabolites of cardiovascular drugs in surface water.