A Comprehensive Examination of UV-VIS Spectrophotometric Methods in Pharmaceutical Analysis Between 2015-2023.

BACKGROUND: Quality control is a system of validated procedures in which many samples, including active pharmaceutical ingredients and final products, are analyzed using standard or validated analytical methods. METHOD: Analytical methods used in analyzing active pharmaceutical ingredients or final products in the pharmaceutical industry can be methods registered in pharmacopeias and developed by the company itself. For this reason, published papers related to pharmaceutical analysis attract analysts and researchers' attention. In this study, pharmaceutical analysis and bioanalysis studies carried out between 2015 and 2023 were examined using Google Scholar, and the recent trends were determined for pharmaceutical analysis. Among the published papers performing conventional analytical techniques for pharmaceutical analysis, those applying UV-VIS spectrophotometry method were selected to predict a future perspective in this study. In addition to the data obtained, the current situation of the pharmaceutical industry was considered to correlate with the obtained data for pharmaceutical analysis. RESULTS: The results were presented with comparative tables and summarizing graphs. Interpreting the results allowed us to determine the trends that pharmaceutical analysis studies will lead in the future. This study can be helpful for researchers working on pharmaceutical analysis in both the industry and academia to predict future trends in pharmaceutical analysis. As a result of the literature research covering the dates 2015-2023, 56% of UV-VIS Spectrophotometric methods are used on pharmaceutical dosage forms, 27% are bulk, 16% are pure, 2% are biological materials, and 0.4% are herbal. Made from materials. Of these studies, 28% were conducted in the 200-240 nm range, 27% were conducted in the 240-300 nm range, and only 44% were conducted at >300 nm. Interpreting the results allowed us to determine the trends that pharmaceutical analysis studies will lead in the future. CONCLUSION: This study can be helpful for researchers working on pharmaceutical analysis in both the industry and academy side to predict future trends for pharmaceutical analysis.

Adapting Fabric Phase Sorptive Extraction as an Innovative Multitool for Sample Transfer and Extraction in Pharmacokinetic Analysis Followed by LC-MS Determination of Levofloxacin in Plasma Samples.

Fabric phase sorptive extraction (FPSE) is a simple microextraction technique that allows analytes to be rescued from matrix components while using a small volume of samples to analyze complex biological systems. This study used FPSE as a microextraction tool and a sample storage and transfer device. Levofloxacin as a model molecule was applied intravenously (IV) to New Zealand male rabbits. The samples were simultaneously extracted by using FPSE and protein precipitation methods. The final solutions were analyzed using LC-MS equipped with an ACE C18 LC Column (150 mm × 4.6 mm, 5 µm) at 25 °C employed in isocratic elution mode using solution A (0.1% formic acid in water)/solution B (0.1% formic acid in acetonitrile) (80:20, v/v). The total analysis time was less than 15 min. The developed method was validated using the ICH M10 bioanalytical method validation and study sample analysis guidelines. The results obtained using FPSE were statistically identical to those obtained using protein precipitation. The plasma samples applied onto FPSE (10 µL onto 1.0 cm × 1.0 cm Biofluid Sampler) were stored in three different temperatures [refrigerator (2-8 °C), at ambient temperature (20 ± 5 °C), and in the stability cabinet (40 °C, 75% humidity)] and three different storage conditions (Eppendorf tubes, plastic containers, and straw paper envelopes). Levofloxacin in plasma samples adsorbed by FPSE biofluid sampler remained stable at 2-8 °C in Eppendorf tubes for at least 1 week. This study showed that FPSE could be used as a sample storage and transfer device for pharmacokinetic applications that need to work with small sample volumes and discard aggressive cold chains to store and transfer the plasma samples.

An Isolated Perfused Rat Liver Model: Simultaneous LC-MS Quantification of Pitavastatin, Coproporphyrin I, and Coproporphyrin III Levels in the Rat Liver and Bile.

The isolated perfused rat liver (IPRL) model provides a mechanistic understanding of the organic-anion-transporting polypeptide (OATP/Oatp)-mediated pharmacokinetics in the preclinical evaluation, which often requires the use of control substrates (i.e., pitavastatin) and monitoring endogenous biomarkers (coproporphyrin I and III). This study aimed to develop and validate an LC-MS method allowing the simultaneous quantification of pitavastatin, coproporphyrin I (CPI), and coproporphyrin III (CPIII) in rat liver perfusion matrices (perfusate, liver homogenate, bile). The analysis was performed on a C18 column at 60 °C with 20 µL of sample injection. The mobile phases consisted of water with 0.1% formic acid and acetonitrile with 0.1% formic acid with a gradient flow of 0.5 mL/min. The assay was validated according to the ICH M10 Bioanalytical Method Validation Guideline (2022) for selectivity, calibration curve and range, matrix effect, carryover, accuracy, precision, and reinjection reproducibility. The method allowing the simultaneous quantification of pitavastatin, CPI, and CPIII was selective without having carryover and matrix effects. The linear calibration curves were obtained within various calibration ranges for three analytes in different matrices. Accuracy and precision values fulfilled the required limits. After 60 min perfusion with pitavastatin (1 µM), the cumulative amounts of pitavastatin in the liver and bile were 5.770 ± 1.504 and 0.852 ± 0.430 nmol/g liver, respectively. CPIII was a more dominant marker than CPI in both liver (0.028 ± 0.017 vs 0.013 ± 0.008 nmol/g liver) and bile (0.016 ± 0.011 vs 0.009 ± 0.007 nmol/g liver). The novel and validated bioanalytical method can be applied in further IPRL preparations investigating Oatp-mediated pharmacokinetics and DDIs.

Untargeted metabolomics to discriminate liver and lung hydatid cysts: Importance of metabolites involved in the immune response.

The Echinococcus granulosus sensu lato species complex is responsible for the neglected zoonotic disease known as cystic echinococcosis (CE). Humans and livestock are infected via fecal-oral transmission. CE remains prevalent in Western China, Central Asia, South America, Eastern Africa, and the Mediterranean. Approximately one million individuals worldwide are affected, influencing veterinary and public health, as well as social and economic matters. The infection causes slow-growing cysts, predominantly in the liver and lungs, but can also develop in other organs. The exact progression of these cysts is uncertain. This study aimed to understand the survival mechanisms of liver and lung CE cysts from cattle by determining their metabolite profiles through metabolomics and multivariate statistical analyses. Non-targeted metabolomic approaches were conducted using quadrupole-time-of-flight liquid chromatography/mass spectrometry (LC-QTOF-MS) to distinguish between liver and lung CE cysts. Data processing to extract the peaks on complex chromatograms was performed using XCMS. PCA and OPLS-DA plots obtained through multiple statistical analyses showed interactions of metabolites within and between groups. Metabolites such as glutathione, prostaglandin, folic acid, and cortisol that cause different immunological reactions have been identified both in liver and lung hydatid cysts, but in different ratios. Considering the differences in the metabolomic profiles of the liver and lung cysts determined in the present study will contribute research to enlighten the nature of the cyst and develop specific therapeutic strategies.

Plasma metabolomics for diagnostic biomarkers on ectopic pregnancy.

Metabolomics is a relatively novel omics tool to provide potential biomarkers for early diagnosis of the diseases and to insight the pathophysiology not having discussed ever before. In the present study, an ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was employed to the plasma samples of Group T1: Patients with ectopic pregnancy diagnosed using ultrasound, and followed-up with beta-hCG level (n = 40), Group T2: Patients with ectopic pregnancy diagnosed using ultrasound, underwent surgical treatment and confirmed using histopathology (n = 40), Group P: Healthy pregnant women (n = 40) in the first prenatal visit of pregnancy, Group C: Healthy volunteers (n = 40) scheduling a routine gynecological examination. Metabolite extraction was performed using 3 kDa pores - Amicon® Ultra 0.5 mL Centrifugal Filters. A gradient elution program (mobile phase composition was water and acetonitrile consisting of 0.1% formic acid) was applied using a C18 column (Agilent Zorbax 1.8 µM, 100 x 2.1 mm). Total analysis time was 25 min when the flow rate was 0.2 mL/min. The raw data was processed through XCMS - R program language edition where the optimum parameters detected using Isotopologue Parameter Optimization (IPO). The potential metabolites were identified using MetaboAnalyst 5.0 and finally 27 metabolites were evaluated to be proposed as potential biomarkers to be used for the diagnosis of ectopic pregnancy.

Effects of genetic polymorphisms of CYP2J2, CYP2C9, CYP2C19, CYP4F2, CYP4F3 and CYP4A11 enzymes in preeclampsia and gestational hypertension.

INTRODUCTION: The aim of this study was to investigate the effects of cytochrome P450 (CYP) 2J2, CYP2C9, CYP2C19 and CYP4F2, CYP4F3 and CYP4A11 genetic polymorphisms in preeclampsia and gestational hypertension (GHT) patients in a sample of Turkish population. MATERIALS-METHODS: Patients (n = 168; 110 GHT and 58 preeclampsia) and healthy pregnant women (n = 155, controls) participated in the study. For genotyping, polymerase chain reaction (PCR) and restriction analysis (RFLP) were used. Substance levels were measured using LC-MS. RESULTS: Plasma DHET levels in GHT and preeclampsia patients were significantly lower than those in the control group (62.7%, 66.3% vs.100.0%, respectively, p < 0.0001). An increase in CYP2J2*7 allele frequency was observed in the preeclampsia group, as compared to GHT group (12.1% vs. 4.5%; odds ratio, O.R. = 2.88, p < 0.01). The frequencies of CYP2C19*2 and*17 alleles were higher in GHT group as compared to the control group (17.7% vs. 11.6%, O.R. = 1.99, p < 0.01; and 28.6% vs.18.4%, O.R. = 2.03, p < 0.01, respectively). An increased frequency of CYP4F3 rs3794987 G allele was found in GHT group as compared to the control group (48.0% vs. 38.0%; O.R. = 1.53, p < 0.01). DISCUSSION: DHET plasma levels were significantly reduced in hypertensive pregnant groups as compared to the control group. The allele frequency distributions for CYP2J2*7, CYP2C19 *2, *17 and CYP4F3 rs3794987 were significantly different in hypertensive pregnant patients as compared to the healthy control subjects. Our results may suggest that investigated genetic polymorphisms may be useful in diagnosis and clinical management of GHT and preeclampsia patients.

A combination of Q-TOF LC/MS and LC-MS/MS based metabolomics in pediatric-onset multiple sclerosis demonstrates potential biomarkers for unclassified patients.

BACKGROUND: Metabolomics has the potential to provide putative biomarkers and insights into the pathophysiology and diagnosis of pediatric multiple sclerosis (pMS), which is an inflammatory demyelinating disorder of the central nervous system with a broad spectrum of clinical manifestations. In this study, we aimed to investigate serum metabolomics in pMS to help elucidate the pathophysiology of MS. METHODS: An untargeted approach was applied using the quadrupole time-of-flight liquid chromatography/mass spectrometry (Q-TOF LC/MS) method to study plasma metabolites in patients with pMS (n = 33), patients with unclassified central nervous system demyelinating diseases (n = 6), and age-matched healthy control subjects (n = 40). The patient and control groups were compared for metabolites and the normalized peak areas differed statistically (p < 0.05), showing at least a 1.25-fold change between groups. Bioinformatic tools combined with a clinical perspective were employed for the identification of the putative metabolites. In addition to the untargeted metabolomics approach, targeted LC-MS/MS metabolite analysis was employed to compare the pMS group with the control group. RESULTS: Significant differences between the patient and control groups were noted for tyramine, 4-hydroxyphenylacetaldehyde, sphingosine/3-dehydrosphinganine, prostaglandins/thromboxane A2, 20-hydroxy-leukotriene E4, 3α,7α,12α-trihydroxy-5ß-cholestan26-al/calcitriol, pantetheine, ketoleucine/3-methyl-2-oxovaleric acid, L-arginine/D-arginine, coproporphyrinogen III, (S)-reticuline, carnosine, cytidine, and phosphoribosyl pyrophosphate. Additional tests for sphingosine 1-phosphate, sphingophosphocholines, ceramides, oxysterols, and calcitriol levels yielded significant metabolomic differences for the pMS group compared to the control group. The metabolomic data of 3/6 patients with unclassified demyelinating disorders matched the pMS group; their follow-up verified the diagnosis of pMS. DISCUSSION: In general, plasma metabolites related to sphingolipid metabolism, myelin products, inflammatory pathways, mitochondrial dysfunction, and oxidative stress were found to be altered in cases of pMS. The method applied in this study, combining untargeted analysis with a targeted approach, can be applied to larger series of cases of pMS and other demyelinating disorders for further validation.

Differential role of prolyl hydroxylases on mitochondrial function of HL-1 cells in a model of iron deficiency.

Iron deficiency is observed in nearly half of the heart failure patients whilst closely correlated with mitochondrial dysfunction. Besides the structural roles in mitochondria, iron is also the cofactor of the hypoxia inducible factor (Hif) degradating enzyme, prolylhydroxylase, thereby Hif accumulation and its related metabolic effects commonly involve in iron deficiency. In this study, we used atrium derived HL-1 cells to investigate the effects of iron depletion on mitochondrial function under in vitro conditions. We aimed to discriminate the Hif dependent effects of iron deprivation on mitochondrial function to reveal the mechanisms leading to cardiac failure. For this purpose, HL-1 cells were either directly incubated with the iron chelating agent deferoxamine (DFO) or with dimethyloxalylglycine (DMOG, inhibitor of prolylhydroxylase). Mitochondrial function was evaluated by measuring cellular ATP content and mitochondrial potential (Ψ). According to our results, 48 h of DFO incubation affected cell viability and ATP production through further mechanisms additional to Hif-1α accumulation. Unlike DMOG group, DFO incubation did not disturb mitochondrial function probably due to its low permeability. Whether or not, prolyl hydroxylase inhibition without iron depletion may negatively affect mitochondrial function through Hif dependent mechanisms.

Review on Characteristics and Analytical Methods of Rivaroxaban.

Rivaroxaban (RIV) is an oral anticoagulant that is the first available orally active direct inhibitor of factor Xa. This study focuses on a critical review of the mechanisms of action, characteristics, operations, physicochemical properties of RIV, and analytical methodologies to quantify the concentration of the agent in bulk, pharmaceutical formulations, dissolution media, and biological samples. The major analytical methodology for the determination of RIV is reverse-phase HPLC coupled with UV detection and LC-MS/MS. This technique is particularly beneficial to detect and analyze RIV in plasma samples. The methodologies published in literature until recently were tabulated and the sample preparation techniques prior to analyzes of the biological matrix were discussed. Based on this critical literature screening, it was concluded that the researchers may easily apply or modify the published methodologies depending on their purpose on further studies since the chemical and physical properties of RIV allows this agent to be extracted and analyzed by employing different analytical strategies.

ltrafiltration-based sample preparation and HPLC-UV determination of diclofenac in human plasma samples.

The sample preparation step is the initial step in pharmaceutical analysis. While ultrafiltration is a well-known technique used in the food and pharmaceutical industries, it has rarely been used to measure the plasma concentration of active pharmaceutical ingredients. This study aimed to analyze diclofenac sodium (DS) in human plasma samples using ultrafiltration-based sample preparation before high-performance liquid chromatography (HPLC) analysis. The advantages and limitations of ultrafiltration-based sample preparation in bioanalysis were evaluated by comparing the results with conventional methods. The precipitating agent was used before ultrafiltration. The analysis was carried on an HPLC-UV system with a C18 column (250 ×4.6 mm, 5 µm) and acetonitrile : phosphate buffer (pH 3.0, 10 mM) (70 : 30 v/v) was used as the mobile phase. The bioanalytical method was validated according to FDA guidelines and applied to spiked samples of DS in commercial human plasma samples. The LOD and LOQ values were 0.006 µg mL-1 and 0.020 µg mL-1, respectively. The method was linear in the range of 0.025-0.50 µgmL-1 with excellent determination coefficients (R2 > 0.9991). The findings of this analysis with low LOD and LOQ values and high recovery values with high trueness and precision proved the matrix minimizing the effect of the presented sample preparation technique.

Fabric phase sorptive extraction combined with high-performance liquid chromatography-photodiode array detection for the determination of tazarotene in gel dosage forms.

Tazarotene, a member of the acetylenic class of retinoids, is a third-generation prescription topical retinoid sold as a cream, gel, or foam. In its gel or cream formulations, tazarotene is at a concentration of either 0.1 % or 0.05 %. Fabric phase sorptive extraction membranes are used to selectively isolate and preconcentrate target analytes from different sample matrices. In this study, the tazarotene gel formulation was directly applied to fabric phase sorptive extraction membranes and extracted through a mixture of acetonitrile and water (80:20, v/v) to obtain a clean product free of colloidal suspension of tazarotene gel formulation. The final solutions were injected into an HPLC system equipped with a Zorbax 5 µm Phenyl-Hexyl LC Column (250 × 4.6 mm). Injection volume was 50 µL and UV detection was performed at 326 nm. The flow rate was 1.0 mL min-1 while using an isocratic elution with a mixture of ammonium acetate (50 mM) and methanol (15:85, v/v) as the mobile phase. The method was validated according to ICH guideline Q2 (R1) and successfully applied to gel formulations including 0.01 % tazarotene. This is the first reported application of fabric phase sorptive extraction in the analyses of gel formulations. The capability of fabric phase sorptive extraction membranes to clean up the sample matrix and prepare active pharmaceutical ingredients to be analyzed with acceptable recovery (>98.0 %) and reproducibility may encourage quality control laboratories to use fabric phase sorptive extraction in routine applications.

Polycationic cyclodextrin nanoparticles induce apoptosis and affect antitumoral activity in HepG2 cell line: An evaluation at the molecular level.

Hepatocellular carcinoma (HCC) is a highly metastatic primary liver cancer generating molecular alterations that end up escaping the apoptotic machinery and conferring multidrug resistance. Targeted medicines with increased and selective cytotoxicity and minimal drug resistance are essential for the treatment of HCC. In this study, a self-assembled polycationic (PC) amphiphilic ß-cyclodextrin (ßCDC6) nanoparticle formulation was characterized and its efficacy over HCC cell line HepG2 was evaluated in terms of cytotoxicity, apoptotic potential, chemosensitivity and mitochondrial balance utilizing biochemical, gene expression and proteomic approaches without encapsulating an anti-neoplastic agent. Blank PC ßCDC6 exerted an anti-proliferative effect on 3D multicellular HepG2 spheroid tumors. These nanoparticles were able to trigger apoptosis proved by caspase 3/7 activity, gene expression and flow cytometry studies. The subjection of PC restored the chemosensitivity of HepG2 cells by suppressing the function of p-glycoprotein. The proteomic studies with Q-TOF LC/MS revealed 73 proteins that are aberrantly encoded after cells were treated with the blank PC. Metabolomic analysis further confirmed the shift in certain biological pathways. Thus, we confirmed that the hepatocellular carcinoma-targeting ßCDC6 PC nanoparticles induce apoptosis, lower the rate of cell proliferation, hinder multidrug resistance and they are convenient carriers for eventual therapeutic administrations in HCC patients.

Could Targeting HMGB1 be Useful for the Clinical Management of COVID-19 Infection?

Since the high mobility group box-1 (HMGB1) molecule had been recognized as a proinflammatory cytokine, which mediates endotoxin lethality of mice, there have been lots of papers about targeting the HMGB1 within the contexts of infection, inflammation, and cancer. The pathogenic impact of HMGB1 to the severe acute respiratory syndrome (SARS) and disease management with herbal formulations targeting this unique protein have already been proposed. However, the failure of the numerous current anti-viral therapies on the ongoing viral infections casts reappraisal of the possible interrelationships regarding the HMGB1 and SARS-CoV-2. COVID-19 pandemic due to the SARS-CoV-2 virus is a currently ongoing challenging global health crisis. There is still not any proven exact treatment of COVID-19 with high level of evidence. In this paper, we focused on the potential usage of external and/or inhalation preparation of antiviral/antibacterial herbal products capable of targeting HMGB1 for the clinical management candidates of the ongoing COVID-19 infection.

Electrochemical Behavior and Square-Wave Stripping Voltammetric Determination of Roflumilast in Pharmaceutical Dosage Forms.

BACKGROUND: Bronchial asthma and chronic obstructive pulmonary disease (COPD) are among the most common chronic diseases. Roflumilast is a novel, potent, selective, and long-acting phosphodiesterase 4 (PDE-4) inhibitor for the treatment of bronchial asthma and COPD. It has anti-inflammatory effects, and it has been shown to reduce exacerbations and improve pulmonary function in patients with COPD. Although there have been some other analytical methodologies reported for the determination of roflumilast in pharmaceutical dosage forms, there has not yet been any electrochemical methodology proposed for determination of this unique active pharmaceutical ingredient in its dosage forms. OBJECTIVE: The aim of this study was to develop an easily applied, selective, sensitive, accurate, and precise square-wave stripping voltammetric (SWSV) method for the determination of roflumilast in its pharmaceutical dosage forms. In addition, the electrochemical behavior of roflumilast was investigated. METHODS: The proposed method was based on electrochemical reduction of roflumilast at a hanging mercury drop electrode (HMDE) in 0.1 M K2HPO4 and 0.1 M Na2B4O7 (1:1, v/v) buffer at pH 5.0. Two reduction peaks were observed at -1150 mV and -1260 mV with 30 s of accumulation time and -850 mV of accumulation potential time versus Ag/AgCl reference electrode. RESULTS: The highest peak current values with the best peak definition were observed at a frequency of 50 Hz, scan increment of 5 mV, and pulse amplitude 25 mV. The proposed method was validated by evaluating validation parameters such as linearity, sensitivity, repeatability, accuracy, precision, selectivity, recovery, robustness, and ruggedness. A good linear correlation (r=0.9948) was obtained between the electrochemical response of roflumilast and its concentration in the range of 0.74-3.05 µg mL-1 under the optimum conditions. The obtained accuracy results were between 2.04% and -2.04% while the relative standard deviation of the results was at least 2.78% for intraday and inter-day studies. The mean recovery for the real applications was 100.63% ± 0.52. The electrochemical behavior of roflumilast was investigated by cyclic voltammetry. The cyclic voltammogram of roflumilast exhibited two peaks and the reduction reaction was reversible. CONCLUSION: This developed and validated SWSV method was applied successfully for the determination of roflumilast in tablet dosage form (Daxas®) to assess active roflumilast content. Since high- -performance liquid chromatography is a dominant technique in industry for quality control of active pharmaceutical ingredients, the finding in the present study demonstrated that square-wave stripping voltammetry could be easily utilized in routine applications to determine roflumilast content in its dosage forms.

Determination of the Physicochemical Properties of Piroxicam.

OBJECTIVES: The aim of this study was to determine the acid dissociation constant (pKa) of piroxicam using high performance liquid chromatography (HPLC) and ultraviolet-visible (UV-Vis) spectrophotometry, and to determine the partition coefficient (Log P), distribution coefficient (Log D), and "Log kw" values of piroxicam using HPLC. MATERIALS AND METHODS: The HPLC studies were performed on a reversed-phase ACE C18 (150x4.6 mm ID, 5 µm) column at a flow rate of 1.0 mL min-1. The detector was set to 360 nm. Log D at different pH values (3.0-6.5) was examined with a phosphate buffer (20 mM) and acetonitrile (30:70 v/v) mixture as the mobile phase. For pKa determination, HPLC studies were performed with a mixture of phosphate buffer (20 mM) and methanol within the pH range of 3.50-6.00. Log kw measurements were performed with phosphate buffer (20 mM) and MeOH (from 20:80 v/v to 10:90 v/v) mixtures within the pH range of 3.50-6.00. UV-Vis spectrophotometric pKa measurements were performed at 285 nm wavelength. RESULTS: The pKa value of piroxicam was found to be 5.3 by HPLC and 5.7 by UV-Vis spectrophotometry. Log P of piroxicam was determined as 1.58 in our experimental conditions. Log D values were 1.57, 1.57, 1.44, 1.13, and 0.46 for pH values of 3.17, 3.79, 4.44, 5.42, and 6.56, respectively. CONCLUSION: In the literature, different Log P (3.1, 2.2, and 0.6) and pKa (6.3 and 4.8) values were reported for piroxicam. The Log P (1.58) and pKa (5.3 and 5.7) values obtained for piroxicam in our study were within the range of the literature values. All these results indicate that different experimental approaches used for the determination of physicochemical properties could provide different values. Although UV spectrophotometry is easy to apply, HPLC is a unique technique for simultaneous determination of pKa, Log D, and Log P values of compounds.

Predictive biomarkers of IgA vasculitis with nephritis by metabolomic analysis.

BACKGROUND: IgA vasculitis (IgAV) is the most common vasculitis of childhood. Renal involvement defines late morbidity of the disease. A better understanding of the pathophysiology of the progression to kidney disease and predictive biomarkers are required for better management of IgAV and its nephritis (IgAVN). OBJECTIVES: An untargeted metabolomics approach was performed to reveal the underlying molecular mechanism of disease pathogenesis and to define potential biomarkers from plasma samples from IgAV and IgAVN patients. METHODS: Forty-five active IgAV patients (H) and six healthy controls (C) were enrolled in the study. Plasma samples were collected on the same day of diagnosis and before any immunosuppressive treatment was initiated. At the time of diagnosis and sample collection, none of the patients had renal involvement. We used Quadrupole Time of Flight Mass Spectrometry (Q-TOF LC/MS) to investigate the alterations in plasma metabolomic profiles. Three separate pools were created: healthy controls (group C), active IgAV patients who did not develop renal involvement (group H), and patients who developed IgAVN at follow up (group N). Peak picking, grouping, and comparison parts were performed via XCMS (https://xcmsonline.scripps.edu/) software. RESULTS: At follow-up, IgAVN developed in 6 out of 45 IgAV patients. The median time of renal involvement development is 23 days (range 5-45 days). Of these, 3 had nephritic proteinuria, one had nephrotic proteinuria, and 2 had microscopic hematuria. There were no significant differences in gender, age, clinical manifestations, and laboratory findings between the six patients who developed renal involvement and those who did not. In multivariate analysis, there was no significant association between any of the defined demographic and clinical characteristics (male sex, gastrointestinal system involvement, joint involvement, CRP, WBC, PLT) and the occurrence of renal involvement. Totally 2618 peaks were detected for group H, N, and C. Among them, 355 peaks were found to be statistically significant and reliable (p<0.05), and 155 of these peaks were found to be changed (fold change >1.5) between the groups C and H, and 66 peaks were found to be changed (fold change >1.5) between the groups H and N. The number of the peaks on the intersection of the peaks found to be different between the groups (C and H) and (H and N) was 39. Based on putative identification results, 15 putatively identified metabolites matched with 11 peaks were presented as biomarker candidates after careful evaluation with a clinical perspective. CONCLUSION: We suggest that DHAP (18:0), prostaglandin D2/I2, porphobilinogen, 5-methyltetrahydrofolic acid, and N-Acetyl-4-O-acetylneuraminic acid/N-Acetyl-7-O-acetylneuraminic acid may serve as biomarkers for predicting kidney disease. Future studies with larger groups of IgAV patients are needed to validate the identified metabolic profile.

Polycystic ovary syndrome in adolescents: Q-TOF LC/MS analysis of human plasma metabolome.

Polycystic ovary syndrome (PCOS) is a hormonal disorder common among women of reproductive age. Women with PCOS may have infrequent or prolonged menstrual periods or excess male hormone levels. Metabolomics provide information on early biochemical changes in patients. Our aim was to find potential biomarkers on metabolome level to notice PCOS in adolescents and propose treatment opportunities based on our findings on metabolome level. In this study, Q-TOF LC/MS based analysis of the plasma samples of 15 healthy adolescents as control group (Group C) were compared with the plasma samples of 15 adolescents having PCOS (Group T). Raw chromatograms were processed on XCMS using Isotopologue Parameter Optimization (IPO) to optimize XCMS parameters. Finally, 2288 peaks were found but 84 of them had fold changes >1.5 based on normalized peak areas and they were statistically different (p < 0.05) between the groups. These peaks were subjected to MetaboAnalyst 4.0 - MS Peaks to Pathways utility for putative identification. The final list based on putative identification were evaluated through a clinical perspective and the statistically proved variation on the metabolite profiles of Group T and Group C presented that PCOS directly affected the lipid metabolism in the body or occurred as a result of a deformation in the lipid metabolism. Lower amount of Gamma-Tocopherol and higher amount of Coenzyme Q9, which is a product of incomplete Coenzyme Q10 biosynthesis, in the plasma samples of adolescent PCOS patients encouraged us to suggest larger randomized placebo controlled studies for Gamma-Tocopherol and Coenzyme Q10 supplements on the disease situation since our findings on metabolome level were in an accordance with the previous clinical findings.

Analysis of plasma protein biomarkers in childhood onset multiple sclerosis.

Multiple sclerosis (MS) manifesting before age 18 years is defined as pediatric MS (pMS). We analysed plasma proteins in pMS by an untargeted proteomic approach. Patients with pMS (Group pMS, n = 33), patients with demyelinating disease not meeting pMS diagnostic criteria (unclassified demyelinating disease, Group U, n = 4) and age-matched healthy subjects (Group C, n = 40) were included. Plasma proteomic analysis was performed using Q-TOF LC/MS. Proteins having fold change >1.2 and found to be statistically different (p < 0.05) between the groups were identified and discussed with a clinical perspective. Group pMS had higher alpha 1B glycoprotein (A1BG), complement factor B (CFB), plasminogen (PLG), alpha-2-antiplasmin (α2-AP, SERPINF2), inter alpha trypsin inhibitor heavy chain H2 (ITIH2), and lower centrosomal protein of 290 (CEP290) and F-box/LRR-repeat protein 17 (FBXL17) concentrations than Group C. Measurements from Group U, whose definite diagnoses were established as pMS (n = 3) and myelin oligodendrocyte glycoprotein antibody-associated disease (n = 1) on follow-up after the study, were statistically close to the results of Group pMS. Plasma protein changes observed in our study were related to the inflammation, coagulation and oxidative stress pathways. If confirmed and validated in larger groups, these results may indicate potential biomarker(s) for demyelinating diseases at proteome level and could encourage studies for the development of novel diagnostic kits.

Development of a RP-HPLC method for simultaneous determination of reference markers used for in-situ rat intestinal permeability studies.

One of the most common techniques for assessing the intestinal absorption characteristics of drugs is single-pass intestinal perfusion (SPIP) method. Metoprolol tartrate (MT, reference standard) and phenol red (PR, zero permeability marker) are the compounds that are normally used in SPIP studies. The aim of this study was to develop a reverse phase high-performance liquid chromatography (RP-HPLC) method combined with UV-detection for the simultaneous determination of MT and PR in the perfusion medium used in SPIP experiments. Elution was performed using a Restek Raptor C18 column (5 µm, 4.6 mm × 250) at a temperature of 25 °C. The mixture of the mobile phase consisted of (MeOH):(Phosphate buffer solution, PBS), (20 mM, pH 3.0 adjusted with ortho-phosphoric acid),(55:45, v/v). Flow rate and column temperature were set at 1.2 mL min-1 and 25 °C, respectively. MT and PR were injected as 20 µL into the HPLC system. UV detection was performed at 227 nm. The obtained retention times were reported as 2.89 and 3.80 min for MT and PR, respectively. The developed RP-HPLC method was validated according to Q2(R1) guideline of The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH). The method was linear within the range of 2-50 µg mL-1 for PR and 10-75 µg mL-1 for MT. The developed RP-HPLC method was successfully applied on determination of MT and PR in perfusion medium. The developed method could be helpful for researchers working on in-situ rat intestinal permeability studies and it could be easily modified on further studies.