Comparative Intra-Subject Analysis of Gene Expression and Protein Abundance of Major and Minor Drug Metabolizing Enzymes in Healthy Human Jejunum and Liver.

First pass metabolism by phase I and phase II enzymes in the intestines and liver is a major determinant of the oral bioavailability of many drugs. Several studies analyzed expressions of major drug-metabolizing enzymes (DMEs), such as CYP3A4 and UGT1A1 in the human gut and liver. However, there is still a lack of knowledge regarding other DMEs (i.e., "minor" DMEs), although several clinically relevant drugs are affected by those enzymes. Moreover, there is very limited intra-subject data on hepatic and intestinal expression levels of minor DMEs. To fill this gap of knowledge, we analyzed gene expression (quantitative real-time polymerase chain reaction) and protein abundance (targeted proteomics) of 24 clinically relevant DMEs, that is, carboxylesterases (CES), UDP-glucuronosyltransferases (UGT), and cytochrome P450 (CYP)-enzymes. We performed our analysis using jejunum and liver tissue specimens from the same 11 healthy organ donors (8 men and 3 women, aged 19-60 years). Protein amounts of all investigated DMEs, with the exception of CYP4A11, were detected in human liver samples. CES2, CYP2C18, CYP3A4, and UGT2B17 protein abundance was similar or even higher in the jejunum, and all other DMEs were found in higher amounts in the liver. Significant correlations between gene expression and protein levels were observed only for 2 of 15 jejunal, but 13 of 23 hepatic DMEs. Intestinal and hepatic protein amounts only significantly correlated for CYP3A4 and UGT1A3. Our results demonstrated a notable variability between the individuals, which was even higher in the intestines than in the liver. Our intrasubject analysis of DMEs in the jejunum and liver from healthy donors, may be useful for physiologically-based pharmacokinetic-based modeling and prediction in order to improve efficacy and safety of oral drug therapy.

Immunosuppressant Adherence Factors Differentiating Compliant and Non-Compliant Kidney Transplant Recipients.

The purpose of this study is to find out the psychological factor characteristic of non-adherence patients. The study population comprised kidney transplant recipients aged between 18 and 82 years at least 3 months post-transplant who voluntarily agreed to answer a couple of fully anonymous questionnaires that questions pertaining to basic data, type of immunosuppressive drugs taken, and standardized questionnaires. Participants were recruited using direct routine, free-of-charge visits to specialist doctors in transplant clinics. There was no significant difference in the percentage of men and women in both adherence and non-adherence groups. Non-adherence patients were significantly younger compared to adherence patients. There was also a significant difference in the patient's level of education. Adherence patients were better educated. No significant differences in criteria such as place of residence, having children or a partner, or way of living were observed. However, the emotion scale correlated negatively with the level of life orientation in both groups, but the level of the emotions scale and distractions subscale was negatively correlated with the level of self-esteem only for the adherence group. In future research, it would be worthwhile to focus on lifestyle and health-promoting behaviors in juxtaposition with the propensity for adherence.

Welfare and Self-Assessment in Patients after Aesthetic and Reconstructive Treatments.

In the last decade, there has been a noticeable increase in the interest in aesthetic and corrective surgery regardless of a patient's age. Both aesthetical and practical considerations are a motivation for patients undergoing plastic surgery. The goal of this study is to analyze dependencies between welfare, self-assessment and body self-perception in patients that qualified for plastic and aesthetic surgical procedures. The study group included 164 female patients, of whom 124 patients filled out a questionnaire before and after surgery. The questionnaire included demographic data and scales such as the Body Esteem Scale, the Rosenberg Self-Esteem Scale-SES, the Satisfaction with Life Scale-SWLS, the Flourishing Scale and the Scale of Positive and Negative Experience-SPANE. The first hypothesis concerned the subjective assessment of body self-perception after the procedure. The results of the study confirm this hypothesis-female patients after surgery rate their body self-perception higher, which indicates a positive influence of plastic and aesthetic surgery that increased in the subjective assessment of 66 examined patients. Moreover, the study revealed a higher self-assessment after procedures. On the other hand, the results indicated that younger patients had a higher body assessment, but there was no increase in self-assessment. Except for breast augmentation surgery, there was no influence on self-assessment and life satisfaction improvement after other surgical procedures. In patients up to 48 years old, after surgery, there was a significant dependence between subjective body self-assessment and all surveyed forms of welfare. In the case of patients after 48 year of age, there was a relationship between life satisfaction and body self-perception both before and after surgical treatment.

Rapid Access in Donation After Circulatory Death (DCD): The Single-Center Experience With a Classic Pathway in Uncontrolled DCD Algorithm.

BACKGROUND: In Poland, 95% of organs for transplantation come from donation after brain death (DBD). In 2010, Poland officially joined the European countries in which donation after circulatory death is accepted by law. Currently, the Pomeranian Medical University Transplant Center is the only active location for uncontrolled donation after circulatory death (uDCD) in Poland. To estimate the results of uDCD kidney transplantation with a classical approach to organ recovery, we analyzed data from an early phase of uDCD program. METHODS: Prospective observation of uDCD kidney allografts (group 1; n = 8) compared with DBD kidney allografts (group 2; n = 30). The organ recovery protocol was set up on rapid abdominal access without regional perfusion before procurement. RESULTS: The organs recovered from uDCD during a 24-month period increased the volume of kidneys transplanted at the center by 9.2%. Delayed graft function was diagnosed in 100% vs 46% of allografts (P = .03), respectively. Nevertheless, early posttransplant follow-up did not reveal any graft loss or recipient death cases in the DCD group. After 12 months of follow-up, the mean glomerular filtration rate was 44.5 vs 57.9 mL/min (P < .02), respectively. Crucial factors for acceptable results of uDCD are strict pretransplant assessment of recovered organs and efficient coordination of the transplant team. CONCLUSIONS: Conservative recovery protocol in uDCD under strict prerequisites is feasible to consider in the organ procurement pathway. Preliminary results provide space for an increase in the organ donor pool.

Assessment of Oxidative Stress Markers in Hypothermic Preservation of Transplanted Kidneys.

Ischemia-reperfusion injury (IRI) after renal transplantation is a complex biochemical process. The first component is an ischemic phase during kidney storage. The second is reperfusion, the main source of oxidative stress. This study aimed to analyze the activity of enzymes and concentrations of non-enzymatic compounds involved in the antioxidant defense mechanisms: glutathione (GSH), glutathione peroxidase (GPX), catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR), glutathione transferase (GST), thiobarbituric acid reactive substances (TBARS), malondialdehyde (MDA), measured in preservation fluid before transplantation of human kidneys (KTx) grafted from brain dead donors. The study group (N = 66) was divided according to the method of kidney storage: Group 1-hypothermic machine perfusion (HMP) in LifePort perfusion pump, n1 = 26, and Group 2-static cold storage (SCS), n2 = 40. The measurements of kidney function parameters, blood count, and adverse events were performed at constant time points during 7-day hospitalization and 3-month follow-up. Kidney perfusate in Group 2 was characterized by significantly more acidic pH (p < 0.0001), higher activity of GPX [U/mgHb] (p < 0.05) and higher concentration of MDA [µmol/L] (p < 0.05). There was a statistically significant improvement of kidney function and specific blood count alterations concerning storage method in repeated measures. There were aggregations of significant correlations (p < 0.05) between kidney function parameters after KTx and oxidative stress markers: diuresis & CAT, Na+ & CAT, K+ & GPX, urea & GR. There were aggregations of significant correlations (p < 0.05) between recipient blood count and oxidative stress markers: CAT & MON, SOD & WBC, SOD & MON. Study groups demonstrated differences concerning the method of kidney storage. A significant role of recipient's gender, gender matching, preservation solution, and perfusate pH was not confirmed, however, basing on analyzed data, the well-established long-term beneficial impact of HMP on the outcome of transplanted kidneys might partially depend on the intensity of IRI ischemic phase and oxidative stress, reflected by the examined biomarkers.

The Role of Endothelins, IL-18, and NGAL in Kidney Hypothermic Machine Perfusion.

Ischemia-reperfusion injury (IRI) occurring after renal transplantation is a complex biochemical process that can be monitored by specific biomarkers. The roles of those are not yet fully elucidated. The aim of this study was to analyze the concentrations of endothelins (ET-1, ET-2, and ET-3), interleukin-18 (IL-18), and neutrophil gelatinase-associated lipocalin (NGAL) during the reperfusion of human kidneys grafted from brain dead donors and later transplanted. The study group (n = 44) was analyzed according to the method of kidney storage: Group 1 underwent hypothermic machine perfusion (HMP) in the LifePort perfusion pump (n = 22), and Group 2 underwent static cold storage (SCS) (n = 22). The analysis of kidney function was performed daily during the first seven days after transplantation. The kidneys in Group 1 were characterized by higher absolute concentrations of ET-1, IL-18, and NGAL, as well as a lower concentration of ET-2 (p = 0.017) and ET-3. The relative increase of ET-1 (p = 0.033), ET-2, and ET-3 during reperfusion was lower in this group, while the relative decrease of NGAL was higher. Group 1 was also characterized by significant decrease of IL-18 (p = 0.026) and a tendency for better kidney function based on the higher total diuresis, higher glomerular filtration rate (GFR), higher potassium level, lower serum creatinine, and lower urea concentration during the seven-day postoperative observation period. The long-term beneficial impact of hypothermic machine perfusion on the outcome of transplanted kidneys may rely on the early modified proceedings and intensity of ischemia-reperfusion injury reflected by the dynamics of the concentrations of examined biomarkers.

The diagnostic value of dual-phase SPECT/CT scintigraphy based on transport kinetics of 99mTc-sestamibi confirmed with histopathological findings in patients with secondary hyperparathyroidism - practical consideration.

BACKGROUND: Dual phase 99mTc-sestamibi SPECT/CT preoperative parathyroid scintigraphy (PPS) is seldom discussed in terms of the transport kinetics of the tracer. OBJECTIVES: To assess the relationship between the characteristic type of tracer transport in particular PPS and histopathological findings in patients with secondary hyperparathyroidism (sHPT). MATERIAL AND METHODS: The study comprised 27 patients (13 females and 14 males) with sHPT. Based on tracer accumulation in early phase (EP) and delayed phase (DP), the following types of accumulation for PPS(+) lesions were identified: EP(-)/ DP(+) (type I), EP(+)/DP(+) (type II), EP(+)/DP(-) (type III). EP(-)/DP(-) (type IV) lesions constituted PPS(-) group invisible in SPECT/CT. Overall, 69 lesions 59 PPS(+) and 10 PPS(-) were evaluated histopathologically. RESULTS: Among SPECT/CT PPS(+), types I, II and III occurred in 9 (15%), 49 (83%), and 1 (2%) lesions, respectively. The frequency of histopathological diagnosis of normal and abnormal (APG - adenoma or hyperplasia) parathyroid gland, as well as non-parathyroid (thyroid, lymph nodes, or fat) lesions differed significantly between type I, II, and III lesions (p = 0.036). APG histopathological diagnosis was significantly more frequent in lesions with type II uptake than in lesions with type I uptake (76% vs. 33%, p = 0.0197). Type II lesions had significantly higher odds for histopathological diagnosis of APG or NPG than type IV, PPS(-) lesions [odds ratio = 13.1 (95% CI: 2.75 to 63.27)]. CONCLUSIONS: For SHP patients evaluated with SPECT/CT PPS accumulation type I is a weak premise for surgeon to find parathyroid pathology. Only persistent 99mTc-sestamibi accumulation in both phases - equivocal with accumulation type II - effectively differentiates parathyroid and non-parathyroid lesions as well as indicates with high probability the presence of adenoma or hyperplasia. Type III consistent with washout pattern is rare in sHPT.

The effect of genetic variations for interleukin-10 (IL-10) on the efficacy of immunosuppressive therapy in patients after kidney transplantation.

Kidney transplantation is the target method of treating chronic kidney disorders. It improves the comfort of patient life by eliminating the need for repeated dialysis. The aim of the study was to examine the correlation between tacrolimus (TAC) dose and genetic variation for interleukin-10 (IL-10) and its effect on the therapeutic outcome. In addition, the correlations between the IL-10 polymorphism andthe clinical and the biochemical parameters of TAC patients were also analyzed. The study included 209 subjects after kidney transplantation, who received TAC every 12 and 24 h. Drug concentrations in blood, selected morphological and biochemical parameters, and the genetic variation of IL-10 (-1082A > G) which may affect immunosuppressant dosage and risk of acute graft rejection were analyzed. Genetic analyses were performed using real-time PCR. No significant correlations between the clinical and the biochemical parameters and IL-10-1082A > G polymorphism for patients receiving TAC after kidney transplantation were found. The analysis of the correlation between TAC dose and IL-10 genetic variation for the -1082A > G polymorphism revealed that patients with the AA genotype required lower immunosuppressive drug doses (AA: 3.54 ± 2.38 mg/day vs AG: 6.18 ± 5.10 mg/day, GG: 4.44 ± 3.01 mg/day). Furthermore, frequencies of the genotypes for the IL-10 -1082A > G polymorphism were characterized by a significantly higher frequency of the AA genotype among TAC 24 as compared to TAC 12 patients. The results of the study indicated that the IL-10 -1082A > G polymorphism may in fact influence the TAC dose. The biochemical parameters of the renal profile in relation to the IL-10 genetic variations were not indicative of higher risk of acute rejection after transplantation.

Acid-Base Balance Disorders During Kidney Preservation in Cold Ischemia.

BACKGROUND: Acid-base balance disorders are a crucial element of ischemia-reperfusion injury during organ transplantation. Hypoxia during organ procurement and storage cause cellular homeostasis imbalance with impact on further graft function. Acidosis in preserved kidney caused by lactate accumulation may have an important role as a common denominator of various pathways leading to cellular damage. METHODS: Our trial sought to answer questions regarding a range of pH alterations in the kidney before the transplantation, their potential cause, and how this may affect further outcome of the kidney transplantation procedure. Perfusion fluid for pH analysis was obtained from perfusion pump (PP) or through kidney flushing at the end of preservation depending on the storage method. RESULTS: A total of 66 sample results were collated with the data from the transplant registry, hospitalization, and outpatient department. Statistical analysis was conducted linking pH results with factors related to donor, recipient, preservation, and outcome according to designed schematics. Mean perfusate pH was significantly lower in simple hypothermia (SH) vs the PP storage group (6.77 vs 7.11; P < .001). All samples of perfusate pH in the SH group were below physiological values (<7.35), and in 10% of samples in the SH group, pH >7.00. CONCLUSIONS: We concluded that kidney storage in cold ischemia is associated with organ acidosis independent of preservation method and that SH is correlated with significantly bigger acidosis than storage in PP, which is an important procedure removing an excessive amount of hydrogen ions from kidney microcirculation, decreasing cell damage.

Donors After Circulatory Death: Theme of Present or a Future? The Research in West Poland.

The most urgent issue in transplantology nowadays is to increase the number of donors as replacement of lungs, heart, and liver in end-stage disease remains the only available method to save patients. Donors after brain death (DBD), these after irreversible cessation of brain function, represent 95% of all donors. On the contrary, donors after circulatory death (DCD), namely donors after irreversible detention of circulation, a group of great potential, is totally unused. The survey was done among 500 people from the medical staff of the intensive care unit and intensive cardiological care where the probability of receiving anonymous donation after circulatory death is the highest, yet only 368 people had completed the survey and their cases were taken into consideration as far as the study was concerned. The survey was conducted in the form of a self-projected questionnaire based on the Hospital Attitude Survey. The study showed that 98.4% of respondents accept the transplant. As many as 93.1% of people did not know the Maastricht classification, and 57.5% claimed that in Poland there is permission to take organs from people with a nonbeating heart. Ninety percent of respondents expressed their willingness to participate in training, and 70% of them were interested in the subject of the training presented in the questionnaire. At a time of such immense need for organs and such a huge disparity in the number of donors and recipients, DCD type of transplantation may be an alternative for patients whose waiting time for donation from a DBD would total a few years.

Effect of Multidrug-Resistant 1 (MDR1) and CYP3A4*1B Polymorphisms on Cyclosporine-Based Immunosuppressive Therapy in Renal Transplant Patients.

BACKGROUND Immunosuppressive drugs such as cyclosporine A (CsA) are characterized by a narrow therapeutic range and high interindividual pharmacokinetic variations. Therefore, the effective monitoring of drug serum level is crucial for successful therapy. This variability can be caused by polymorphisms in genes encoding drug transporters and enzymes responsible for biotransformation. The aim of this study was to determine the relationship between CYP3A4*1B and MDR1 polymorphisms and dose requirements to achieve the target therapeutic range for CsA. MATERIAL AND METHODS The study group consisted of 184 patients after kidney transplantation who were treated with immunosuppressive therapy. The MDR1 3435C>T and CYP3A4*1B polymorphisms were determined by the real-time PCR using the LightCycler® 480 device (Roche Diagnostics). RESULTS Patients with the CYP3A4*1/*1 genotype received the lowest mean dose of CsA compared to CYP3A4*1/*1B, and had a higher average drug concentration in the blood. In the case of MDR1 3435C>T polymorphism, we observed that patients with the CC genotype received lower doses of CsA than patients with the CT and TT genotypes. Average drug concentration in the blood was comparable to individuals with different MDR-1 genotypes. Analysis of dependence between both polymorphisms and concentration/dose ratio showed no statistically significant differences. CONCLUSIONS The characterization of CYP3A4*1B and 3435C>T MDR1 polymorphism cannot provide useful guidance for individualizing CsA dosages in renal transplant patients by indicating the optimal dose of these drugs without exposing patients to possible adverse effects associated mainly with nephrotoxicity.

Protein Abundance of Clinically Relevant Drug Transporters in the Human Liver and Intestine: A Comparative Analysis in Paired Tissue Specimens.

Bioavailability of orally administered drugs is partly determined by function of drug transporters in the liver and intestine. Therefore, we explored adenosine triphosphate-binding cassette (ABC) and solute carriers family transporters expression (quantitative polymerase chain reaction) and protein abundance (liquid chromatography tandem mass spectrometry (LC-MS/MS)) in human liver and duodenum, jejunum, ileum, and colon in paired tissue specimens from nine organ donors. The transporter proteins were detected in the liver (permeability-glycoprotein (P-gp), multidrug resistance protein (MRP)2, MRP3, breast cancer resistance protein (BCRP), organic anion-transporting polypeptide (OATP)1B1, OATP1B3, OATP2B1, organic cation transporter (OCT)1, OCT3, organic anion transporter 2, Na+-taurocholate cotransporting polypeptide, monocarboxylate transporter (MCT)1, and multidrug and toxin extrusion 1) and the intestine (P-gp, multidrug-resistance protein (MRP)2, MRP3, MRP4, BCRP, OATP2B1, OCT1, apical sodium-bile acid transporter (only ileum), MCT1, and peptide transporter (PEPT1)). Significantly higher hepatic gene expression and protein abundance of ABCC2/MRP2, SLC22A1/OCT1, and SLCO2B1/OATP2B1 were found, as compared to all intestinal segments. No correlations between hepatic and small intestinal protein levels were observed. These observations provide a description of drug transporters distribution without the impact of interindividual variability bias and may help in construction of superior physiologically based pharmacokinetic and humanized animal models.

Expression of clinically relevant drug-metabolizing enzymes along the human intestine and their correlation to drug transporters and nuclear receptors: An intra-subject analysis.

The oral bioavailability of many drugs is highly influenced not only by hepatic but also by intestinal biotransformation. To estimate the impact of intestinal phase I and II metabolism on oral drug absorption, knowledge on the expression levels of the respective enzymes is an essential prerequisite. In addition, the potential interplay of metabolism and transport contributes to drug disposition. Both mechanisms may be subjected to coordinative regulation by nuclear receptors, leading to unwanted drug-drug interactions due to induction of intestinal metabolism and transport. Thus, it was the aim of this study to comprehensively analyse the regional expression of clinically relevant phase I and II enzymes along the entire human intestine and to correlate these data to expression data of drug transporters and nuclear receptors of pharmacokinetic relevance. Gene expression of 11 drug-metabolizing enzymes (CYP2B6, 2C8, 2C9, 2C19, 2D6, 3A4, 3A5, SULT1A, UGT1A, UGT2B7, UGT2B15) was studied in duodenum, jejunum, ileum and colon from six organ donors by real-time RT-PCR. Enzyme expression was correlated with expression data of the nuclear receptors PXR, CAR and FXR as well as drug transporters observed in the same cohort. Intestinal expression of all studied metabolizing enzymes was significantly higher in the small intestine compared to colonic tissue. CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP3A4/5, SULT1A, UGT1A and UGT2B7 expression increased from the duodenum to jejunum but was markedly lower in the ileum. In the small intestine, that is, the predominant site of drug absorption, the highest expression has been observed for CYP3A4, CYP2C9, SULT1A and UGT1A. In addition, significant correlations were found between several enzymes and PXR as well as ABC transporters in the small intestine. In conclusion, the observed substantial site-dependent intestinal expression of several enzymes may explain regional differences in intestinal drug absorption. The detected correlations between intestinal enzymes, transporters and nuclear receptors provide indirect evidence for their coordinative expression, regulation and function in the human small intestine.

Biocompatibility of synthetic ultraviolet radiation cross-linked polymers - Subcutaneous implantation study.

Photo-cross-linked polymers have attracted a lot of attention in the biomedical field. The main benefits of these materials are related to the fact that they are most of the time viscous liquids or pastes that adapt a custom and fixed shape on demand of the user. Present study deals specifically with the biological response upon subcutaneous implantation of four different materials in rabbits. In the study 20 rabbits were divided into four groups (each five rabbits): Groups 1-3 were implanted with tested new obtained by us macromonomers (P1838-DMA; P1838-UR; PDEGA-UR - respectively), while group 4 (control) was implanted with the mesh (PLA) routinely used for surgical treatment of a hernia. The new compounds were polarized earlier using ultraviolet radiation to obtain cross-linked networks. The polymers in the form of discs were then implanted subcutaneously in dorsal region of rabbits. After 28 days polymers were explanted and examined. Microscopic observation evaluated: thickness of the connective tissue capsule around the discs, cells of inflammatory response, disc surface erosion, spectroscopic analysis. The examined materials cause no chronic inflammation, abscesses or tissue necrosis, and the biological response is similar to observed in control group. Therefore, new synthetic materials could be considered as biocompatible and safe. Materials undergo slow degradation of ester bonds and surface erosion and degradation products could be eliminated probably by phagocytosis. On the basis on the afore mentioned knowledge, we formulated hypothesis, that the new polymers are well tolerated by the adjacent tissues. The aim of the following study was to examine reaction of the tissue on new types of prepolymerized material implanted subcutaneously. The obtained results suggest, that the new UV cross-linked polymers do not affect negatively on the connective tissue that is in the contact with the implants. Furthermore, the used materials are in the liquid form, thus they could be easily performed in in minimally invasive laparoscopic treatment of abdominal hernias. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1889-1897, 2019.

Correlation Between Stem and Progenitor Cells Number and Immune Response in Patients After Allogeneic Kidney Transplant.

BACKGROUND Stem and progenitor cells are of great interest in all medical procedures involving tissue regeneration. There is a consensus that the use of stem cells after solid organ transplantation may play a role in tissue repair and in immunosuppression. The aim of this study was to determine possible relations between stem cell count and the immune response in a group of patients after kidney transplantation. MATERIAL AND METHODS The study was conducted on a group of 100 patients who underwent kidney transplantation. The following phenotypic markers of the studied cell subpopulations were adopted: Treg cells (CD3+CD4+CD25high), circulating hematopoietic cells (CD34+CD133+CD45+CD38-), and non-hematopoietic cells (Lin-CXCR4+CD133-CD45-). Cell subpopulations were assessed using LSRII flow cytometer (BD Biosciences, San Jose, CA, USA). RESULTS Positive correlation was observed between non-hematopoietic stem cells percentage and recipient's platelets count (P=0.04). Moreover, a higher percentage of non-hematopoietic cells was accompanied by lower numbers of B lymphocytes (P=0.03) and Treg cells (P=0.02). CONCLUSIONS Our study revealed significant associations between the intensity of ongoing immune response processes and tissue damage, and the release of stem and progenitor cells into circulation. These findings suggest their role in the stimulation of protective processes in terms of graft regeneration.

Quantitative characterization of UDP-glucuronosyltransferase 2B17 in human liver and intestine and its role in testosterone first-pass metabolism.

Protein abundance and activity of UGT2B17, a highly variable drug- and androgen-metabolizing enzyme, were quantified in microsomes, S9 fractions, and primary cells isolated from human liver and intestine by validated LC-MS/MS methods. UGT2B17 protein abundance showed >160-fold variation (mean ±â€¯SD, 1.7 ±â€¯2.7 pmol/mg microsomal protein) in adult human liver microsomes (n = 26) and significant correlation (r2 = 0.77, p < 0.001) with testosterone glucuronide (TG) formation. Primary role of UGT2B17 in TG formation compared to UGT2B15 was confirmed by performing activity assays in UGT2B17 gene deletion samples and with a selective UGT2B17 inhibitor, imatinib. Human intestinal microsomes isolated from small intestine (n = 6) showed on average significantly higher protein abundance (7.4 ±â€¯6.6 pmol/mg microsomal protein, p = 0.016) compared to liver microsomes, with an increasing trend towards distal segments of the gastrointestinal (GI) tract. Commercially available pooled microsomes and S9 fractions confirmed greater abundance and activity of UGT2B17 in intestinal fractions compared to liver fractions. To further investigate the quantitative role of UGT2B17 in testosterone metabolism in whole cell system, a targeted metabolomics study was performed in hepatocytes (n = 5) and enterocytes (n = 16). TG was the second most abundant metabolite after androstenedione in both cell systems. Reasonable correlation between UGT2B17 abundance and activity were observed in enterocytes (r2 = 0.69, p = 0.003), but not in hepatocytes. These observational and mechanistic data will be useful in developing physiologically-based pharmacokinetic (PBPK) models for predicting highly-variable first-pass metabolism of testosterone and other UGT2B17 substrates.

Protein Abundance of Clinically Relevant Drug-Metabolizing Enzymes in the Human Liver and Intestine: A Comparative Analysis in Paired Tissue Specimens.

This work revises and complements existing findings on the distribution of drug-metabolizing enzymes in the first-pass effect organs. We explored gene expression (quantitative polymerase chain reaction) and protein abundance (liquid chromatography/ tandem mass spectrometry) of CYP1A2, CYP2B6, CYP2C8/9/19, CYP2D6, CYP2E1, CYP3A4/5, UGT1A1/3, UGT2B7/15 in the liver, duodenum, jejunum, ileum, and colon in paired tissues from nine organ donors. All proteins were detected in the liver, but in the intestine CYP2C9/19, CYP2D6, CYP3A4/5, UGT1A1/3, and UGT2B7 were found. CYP3A4 showed comparable abundance in the liver and jejunum, whereas other enzymes were markedly higher in the hepatic tissue. Nearly all detected enzymes showed their highest abundance in the jejunum. Significant correlations between mRNA and protein levels in liver or intestine were found for most enzymes. CYP3A4 and CYP3A5 protein abundance, but not other enzymes, were significantly correlated in the liver and the small intestine. Our data may contribute to an improved understanding of hepatic and intestinal drug metabolism.

Clinically Relevant Multidrug Transporters Are Regulated by microRNAs along the Human Intestine.

Intestinal drug transporters are crucial determinants for absorption and oral bioavailability of drugs. In healthy tissue donors, a recent study revealed profound discrepancies between mRNA expression and protein abundance as well as differences in the protein content between small and large intestine for clinically relevant multidrug transporters as the ATP binding cassette transporter subfamily B member 1 (ABCB1) and subfamily C member 3 (ABCC3) and the solute carrier family 15 member 1 (SLC15A1, PEPT1). As the mechanisms underlying these observations remained unclear, the aim of the present study was to elucidate the intestinal regiospecific microRNA profile under physiological conditions and identify specific microRNAs contributing to the post-transcriptional regulation of major drug transporters. For this purpose, tissue samples were collected from six intestinal sites obtained from six healthy tissue donors. The expression of 754 microRNAs was determined using qRT-PCR based low density arrays, and microRNA expression levels were correlated with transporter protein abundance quantified by targeted proteomics. A total of 241 microRNA-transporter pairs were identified, showing significant negative correlations to protein abundance (p < 0.05). Out of these, for nine pairs, the binding of the microRNA to the respective transporter 3'-UTR was predicted in silico. Besides the already known interactions of miR-27a-3p-ABCB1 and miR-193a-3p-PEPT1, reporter gene assays confirmed binding of miR-192-5p to the ABCC3 3'-UTR (reduction of reporter gene activity by 31%; p = 0.0012), miR-409-3p to the ABCB1 3'-UTR (reduction by 38%; p = 0.0006), and miR-193b-3p as well as miR-27a-3p to PEPT1 3'-UTR (reduction by 49% (p = 0.0012) and 20% (p = 0.0043), respectively). These results suggest that mucosal microRNA expression contributes to the explanation of discrepancies between mRNA expression and protein abundance as well as site-dependent differences in protein content along the human intestine under physiological conditions, as exemplified for ABCB1, ABCC3, and PEPT1.

Semi-quantitative method for the assessment of focal lesions in parathyroid scintigraphy with relation to histopathology: a prospective study.

BBACKGROUND: The aim of this paper was to analyse our own semi-quantitative method of assessing focal lesions localised in pre-operative diagnostic scintigraphy of primary hyperparathyroidism (PHPT) using 99mTc-MIBI with washout and comparing these data with the result of the histopathological examination (HP). MATERIAL AND METHODS: A total of 40 (37 female, 3 male, average age 58.7 years) patients with a suspicion of PHPT were enrolled for prospective analysis. Dual phase planar and SPECT/CT examination with 99mTc-MIBI were performed. The tumour to background ratios in the 10th and 120th minute were calculated (TBR10 and TBR120) on the basis of the planar acquisition. PTH, ionised calcium and phosphate levels were measured. Parathyroid surgery alone or combined with subtotal/total thyreoidectomy was conducted in 23 (57.5%) and 17 (42.5%) patients, respectively. A HP was performed in all patients. RESULTS: Average concentration of PTH in the whole group was 243.95 pg/ml. There was a statistically significant correlation between medians of PTH concentration and parathyroid histopathological results (p = 0.01). A total of 45 lesions of increased uptake were found in 32 (80.0%) and 34 (85%) patients in the early phase and the delayed phase, respectively. The post-operative material contained 20 (44.5%) parathyroid adenomas, 11 (24.5%) cases of hyperplasia, 2 (4.4%) cancers, 4 (8.9%) cases of normal parathyroid tissue, 2 (4.4%) lymph nodes and 6 (13.3%) cases of thyroid gland tissue. The medians of TBR10 and TBR120 for lesions examined in the HP were respectively: 3.64 and 2.59 for adenoma; 3.08 and 2.18 for hyperplasia; 7.7 and 5.5 for parathyroid cancer, 4.89 and 3.16 for normal tissue and 5.26 and 2.95 for lymph nodes or thyroid gland tissue. A high correlation coefficient of TBR10 to TBR120 in the parathyroid adenoma and parathyroid hyperplasia groups was observed with r = 0.867 and r = 0.964, respectively. The ρr correlation coefficient of TBR10 to TBR120 for normal parathyroid was 0.4. There was a statistically significant association between the HP and TBR10 medians (p = 0.047), but not between histopathology and TBR120 medians (p = 0.840). CONCLUSIONS: The washout technique in pre-operative 99mTc-MIBI scintigraphy is effective in detecting lesions of the parathyroid (cancer, adenoma, hyperplasia, normal tissue of the parathyroid). Parathyroid cancers in semi-quantitative analysis were characterised by a slightly higher TBR. However, it is impossible to differentiate lesions based on this data. Histopathology results are significantly associated with TBR and PTH.

Evaluation of renal graft function based on standard mathematical formulas.

BACKGROUND: Creatinine is a standard marker for estimation of the transplanted kidney function. Concentration values are used in mathematical equations for GFR (glomerular filtration rate) calculation, with MDRD (modification diet in renal disease) being most commonly used. Cystatin C is an alternative marker for changes in glomerular filtration, which is also used in eGFR (estimated GFR) formulas. The aim of this study was to reveal eGFR <60 ml/min/1.72 m(2) in a population of patients after renal transplant, with stable graft function, using different formulas. MatERIAL AND METHODS: A group of 100 patients (56 females and 44 males) aged 20-78 years, took part in this study. Renal transplantation was conducted from 10 years to 10 months prior to the study. Estimated GFR was calculated with 4 formulas: MDRD, CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration), CKD-EPI cys (using cystatin C), and CKD-EPI mix (using creatinine and cystatin C). We used electronic calculators available on the National Kidney Foundation and the Nephron Information Center websites. RESULTS: The occurrence of eGFR values <60 ml/min/1.73 m(2) was 28% according to MDRD formula, 23% according to CKD-EPI, 25% according to CDK-EPI cys, and 26%according to CDK-EPI mix. CONCLUSIONS: Occurrence of GFR <60 ml/min/0.73 m(2) was the highest when calculated by MDRD formula, and the lowest when calculation was done with CDK-EPI. The significant discrepancy with different eGFR formula testing suggests the need for further research to find the best marker and/or formula for graft function estimation.