Volume 37, Issue 3

This review aimed to summarize the pharmacogenetic studies of the most commonly used drugs in the chemotherapy of gastrointestinal (GI) tumors: oxaliplatin, irinotecan, and fluoropyrimidines. So far, it has not been possible to develop an effective genotype-based approach for oxaliplatin. More and more evidence is emerging in favor of the fact that the choice of a dose of fluorouracil based on pharmacogenetic testing according to DPYD*2A , can be not only effective but also cost-effective. Additional, well-planned trials of the UGT1A1 genotype-based approach to irinotecan therapy are predicted to reduce adverse drug events in people with the UGT1A1*28/*28 genotypes and improve treatment efficacy in the rest of the patients, which might be cost-effective.

Low dose methotrexate (MTX) is commonly used in the treatment of rheumatoid arthritis. The clinical effect is mediated by its metabolite, methotrexate polyglutamate (MTX-PGn). The drug exhibits high interindividual pharmacokinetic variability and the optimal MTX dose is different among individuals. Thus, several MTX population pharmacokinetic (PopPK) models were developed to characterize factors affecting MTX pharmacokinetic variability. This review summarizes significant predictors for MTX pharmacokinetics and identifies knowledge gaps to be further examined. A total of 359 articles were identified from a systematic search of four databases: PubMed, Science Direct, and CINAHL Complete. Of these eight studies were included. Most studies investigated influential factors on MTX pharmacokinetics, but information on MTX-PGn is limited, with only one study performing a parent-metabolite (MTX-PG3) model. MTX pharmacokinetics was described using a two-compartment model with first-order elimination in most studies, with the MTX clearance ranging from 6.94 to 12.39 L/h. Significant predictors influencing MTX clearance included weight, creatinine clearance, sex, OATP1B3 polymorphism, and MTX multiple dosing. While body mass index and red blood cell counts were significant predictors for MTX-PG3 clearance. Providing that MTX-PGn plays a crucial role in clinical effect, further studies should determine other factors affecting MTX-PGn as well as its relationship with clinical response.

Objectives Human cytochrome P450 3A4 is the most abundant hepatic and intestinal Phase I enzyme that metabolizes approximately 60% marketed drugs. Simultaneous administration of several drugs may result in appearance of drug–drug interaction. Due to the great interest in the combination therapy, the exploration of the role of drug as “perpetrator” or “victim” is important task in pharmacology. In this work the model systems based on electrochemically driven cytochrome P450 3A4 for the analysis of drug combinations was used. We have shown that the analysis of electrochemical parameters of cytochrome P450 3A4 and especially, potential of the start of catalysis, Eonset, possess predictive properties in the determination of the leading (“perpetrator”) properties of drug. Based on these experimental data, we concluded, that the more positive potential of the start of catalysis, Eonset, the more pronounced the role of drug as leading medication. Methods Electrochemically driven cytochrome P450 3A4 was used as probe and measuring tool for the estimation of the role of interacting drugs. Results It is shown that the electrochemical non-invasive model systems for monitoring the catalytic activity of cytochrome P450 3A4 can be used as prognostic devise in assessment of drug/drug interacting medications. Conclusions Cytochrome P450 3A4 activity was studied in electrochemically driven system. Method was implemented to monitor drug/drug interactions. Based on the obtained experimental data, we can conclude that electrochemical parameter such as potential of onset of catalysis, Eonset, has predictive efficiency in assessment of drug/drug interacting medications in the case of the co-administration.

Objectives The present study investigated the stability of furosemide under space-flight conditions on board the International Space Station, as well as its pharmacokinetics and pharmacodynamics under conditions simulating exposure to some space-flight factors. Methods Quantitative analysis of furosemide tablets by HPLC was performed before spaceflight (background), then after six months storage under normal ground conditions (control) and under spaceflight conditions (SF). The pharmacokinetics and pharmacodynamics of furosemide were studied in six healthy volunteers after a single oral dose of 40 mg under normal conditions (background) and under anti-orthostatic hypokinesia (ANOH). Results Quantitative content of furosemide in tablets before SF was 40.19 ± 0.28 mg (100.47 ± 0.71%), after 6 months storage: under normal conditions (control) – 39.9 ± 0.39 mg (99.73 ± 0.98%), under SF – 39.24 ± 0.72 mg (98.11 ± 1.80%), which was within the prescribed limits. Studying basic hemodynamic parameters showed that in ANOH conditions 6 h after furosemide administration there was a statistically significant increase of the stroke volume (SV) (+36.5 Δ%), a tendency for increasing of the stroke index (SI) (+36.5 Δ%) and decreasing of the total peripheral resistance (TPR) (−21.9 Δ%) compared to baseline study. Conclusions It has been established that various factors of space flight (overloading, excessive vibration, microgravity, etc.) do not negatively influence the stability of furosemide in tablet form during storage for 6 months on board the International Space Station.

Objectives Cytochrome P450 (CYP450) is a major enzyme system involved in drug metabolism as well as regulation of brain function. Although individual variability in CYP enzymes have been studied in terms of personality traits and treatment effects, no study up to now evaluated CYP polymorphisms in children with attention deficit/hyperactivity disorder (ADHD). We aimed to define the genetic profiles of CYP2D6 and CYP2C19 relevant alleles in children with ADHD according to treatment status and compare the frequencies according to past results. Methods Three hundred and seventeen patients with ADHD-Combined Presentation were enrolled; symptom severity was evaluated by parents and clinicians while adverse effects of previous treatments were evaluated with parent and child reports. Reverse blotting on strip assays was used for genotyping and descriptive and bivariate analyses were conducted. A p-value was set at 0.05 (two-tailed). Results Children were divided into treatment-naïve (n=194, 61.2%) and treatment-resistant (n=123, 38.8%) groups. Within the whole sample PM, EM and UM status according to 2D6 were 3.8% (n=12), 94.3% (n=299) and 21.9% (n=6); respectively. PM, IM, EM and UM status according to 2C19 were 2.5% (n=8), 19.8% (n=63), 48.6% (n=154) and 29.0% (n=92), respectively. No relationship with treatment resistance, comorbidity or gender could be found. Importantly, CYP2C19 UMs were significantly more frequent in ADHD patients compared to previous studies in the general population. Conclusions CYPs may be a rewarding avenue of research to elucidate the etiology and treatment of patients with ADHD.

Objectives The newborn screening (NBS) program in the Republic of Serbia has several decades of tradition, but it has not included any organic acidemias (OA). Therefore, this study aimed to establish the cut-offs of the corresponding NBS markers in the population of healthy newborns. Methods In dried blood samples (DBS) collected from 1,771 healthy newborns, we analyzed levels of propionylcarnitine (C3), isovalerylcarnitine (C5), and glutarylcarnitine (C5DC) using tandem mass spectrometry. Further we calculated the following ratios: C3/acetylcarnitine (C3/C2), C3/palmitoylcarnitine (C3/C16), C5/ free carnitine (C0), C5/C2, C5/C3, C5DC/octanoylcarnitine (C8), and C5DC/C0. Results The cut-offs for methylmalonic acidemia (MMA) or propionic acidemia (PA) were C3>5.73 μmol/L, C3/C2>0.23, and C3/C16>2.36. Based on the study findings, the screening results indicative for isovaleric acidemia (IVA) would include C5>0.372 μmol/L, C5/C0>0.020, C5/C2>0.019, and C5/C3>0.31. Finally, C5DC>0.303 μmol/L, C5DC/C8>7.1, and C5DC/C0>0.019 would justify further testing for glutaric acidemia type I (GA1). The cut-offs were satisfactorily validated via the comparison with worldwide estimates and data for several Caucasian populations. Conclusions The levels of the OA biomarkers in the Serbian population of healthy newborns have a distribution pattern similar to the other world populations. Therefore, the proposed cut-offs represent a reliable starting point for the future development of the OA NBS.

Objectives This study sought to investigate the beneficial effect of kolaviron (KV) (a biflavonoid) isolated from Garcinia kola seed on chronic unpredictable mild stress (CUMS)-induced anxiety- and depressive-like behavior. Methods Male albino mice were randomly divided into six groups (n=8) as follows; Group I: vehicle-control unstressed; Group II: CUMS-control; Group III-V: CUMS + KV 1, 5 or 50 mg/kg, respectively, Group VI: KV (50 mg/kg, p.o.) unstressed mice. Animals were subjected to CUMS for 14 days, followed by estimation of depressive- and anxiety-like behavior from days 14–16. This was followed by biochemical assays for oxidative stress, hypothalamo-pituitary axis, cholinergic, and BDNF signaling. Results CUMS caused significant reduction in time spent in open arms of elevated plus maze test (EPM) and increase in immobility time in tail suspension test (TST) and forced swim test (FST) ameliorated by KV treatments. KV administration also attenuated CUMS-induced malondialdehyde/nitrite generation and decrease in antioxidant enzymes activities in the prefrontal cortex and hippocampus. CUMS increased serum corticosterone, acetylcholinesterase activity, and reduced BDNF level in the PFC and hippocampus were attenuated by KV administration. Conclusions KV prevented CUMS induced anxiety- and depression-like behavior in mice through enhancement of antioxidant defense mechanisms, neurotrophic factors, and cholinergic systems.

Objectives Chronic atopic dermatitis (AD) is an inflammatory skin condition marked by intense pruritus, dry skin, and severe impact on the life quality of the patients. Conventionally, it is managed by using emollients, calcineurin inhibitors, and topical corticosteroids. In Unani medicine, eminent scholars advocated many drug formulations including topical Marham-e-Akbar for effective healing of AD but scientific evidence is scarce. Hence, this study was designed. Methods This was a single-arm clinical trial conducted on 30 participants aged 18–65 years suffering from chronic AD after obtaining written informed consent. The trial intervention was Marham-e-Akbar consisting of Murdār Sang ( Plumbi oxidum) ; Sindūr (red lead); olive oil ( Olea europaea oil); Kath ( Acacia catechu extract); Safeda Kāshgari ( Zinc oxide ); Sirka (vinegar); and Phitkirī ( alum ) to be applied twice daily for 42 days. The objective parameters were SCORAD and DLQI, while the subjective parameters included itching, scaling, and erythema assessed on a customized VAS scale and 4-point Likert scale. Results The pre-post analysis inferred statistically significant attenuation in subjective parameters (itching, scaling, and erythema) and objective scales (SCORAD) and (DLQI) with p<0.001. Conclusions The study findings deduced that Marham-e-Akbar is effective in the amelioration of chronic atopic dermatitis and quality of life of the patients as well.

Objectives Colorectal cancer continues to have one of the highest incidents of occurrence with a rising rate of diagnosis among people under the age of 50. Chemotherapy with irinotecan results in severe gastrointestinal dose-limiting toxicity that is caused by the glucuronidated form of the active metabolite (SN-38G). This study evaluates herbal compounds and analogs to biomodulate the metabolism of IR to decrease dose-limiting toxicity while increasing the amount of the active metabolite. Methods In vitro metabolism using human liver microsomes was conducted with white willow bark (WWB) extract, select specific components of WWB, and analogues to evaluate biomodulation of the IR metabolism. Samples were analyzed using liquid chromatography-tandem mass spectrometry to measure metabolites between reactions with and without herbals components. Results WWB showed an optimal decrease (>80%) in SN-38G and a corresponding increase in SN-38 levels (128%) at a concentration of near 200 μg/mL. Tannic acid produced a 75% decrease in SN-38G with a 130% increase in SN-38 at 10 μg/mL, whereas the treatment with beta-pentagalloyl glucose and various analogues decreased SN-38G by 70% and increased SN-38 by 20% at 10 μg/mL. Conclusions These results suggest naturally occurring compounds from WWB may have the potential to increase potency by increasing the conversion of IR to SN-38 and decrease dose-limiting toxicity of IR chemotherapy by reducing glucuronidation of SN-38.

Objectives Ethno-botanical surveys uncovered the use of Datura stramonium in the management of mental health abnormalities. Antidepressant- and anxiolytic-like activities of hydroethanol leaf extract of D. stramonium (HLDS) in mice and its possible mechanism of action were investigated in this study. Methods The hole-board test (HBT), open field test (OFT), elevated plus maze test (EPMT), and social interaction test (SIT) were used to investigate the anxiolytic-like activity while forced swim test (FST) and tail suspension test (TST) were employed for the antidepressant effect. Mice were pre-treated orally with purified water (10 mL/kg), bromazepam (1 mg/kg), fluoxetine (20 mg/kg) and D. stramonium (25, 50, 100 and 200 mg/kg). One hour post-treatment, mice were subjected to the various tests. Results In HBT, D. stramonium increased the head dips and sectional crossings turnover. D. stramonium increased the number of square crossed and rearings/assisted rearings in OFT. DS increased the time spent in open arms of EPM. In SIT, D. stramonium increased the frequency/duration of interactions. In FST and TST, D. stramonium decreased the duration of immobility which were reversed by doxazosin (α 1 adrenoceptor antagonist) and ondasentron (5-HT 3 receptor antagonist). Conclusions HLDS has anxiolytic- and antidepressant-like activities through modulation of serotoninergic and adrenergic neurotransmissions.

Objectives Breast cancer is the most commonly diagnosed invasive non-skin malignancy in women worldwide, and it is the leading cause of cancer-related deaths in them. Nigella sativa Linn. seed oil has been found to be effective in cancer treatment as well as having anti-cancer properties in some other types of cancers. The study looked into the synergistic cytotoxic effects of N. sativa Linn. seed oil and doxorubicin in the treatment of human breast cancer cells (MCF-7). Methods Nigella sativa Linn. seed oil was used to evaluate its effect on human breast cancer cells, either alone or in conjunction with doxorubicin. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) tests were used to examine cell proliferation and cell viability, while phase-contrast inverted microscopy was used to examine cellular morphology. Furthermore, the role of N. sativa seed oil in decreasing cell tumorigenicity features was highlighted by testing the cancer cell migration using the wound healing assay. Results Results showed that higher concentrations (50 μg/mL) of N. sativa Linn. seed oil changed the breast cancer cell morphology and decreased the cell proliferation and viability. Breast cancer cells treated with black seed oil decreased cell movement after 24 hours compared to the untreated cell in the wound healing assay. Whereas, only the higher concentration of doxorubicin (0.5–2.5 μg/mL) reduced cell proliferation and cell viability. Moreover, the combination treatment of 50 μg/mL of black seed oil with different concentrations of doxorubicin caused a significant cell proliferation reduction and decreased cell viability. The activity was seen optimum at lower concentration (0.1 µg/mL) of doxorubicin. Conclusions There was decreased cell proliferation and cell viability when N. sativa seed oil was used alone or in conjunction with doxorubicin in Breast cancer cells (MCF-7) revealing potential opportunities in the field of cancer treatment.

Objectives The fluoropyrimidine derivatives 5-Fluorouracil and Capecitabine are widely used for the treatment of solid tumors. Fluoropyrimidine metabolism involves a cascade of different enzymes, including MTHFR enzyme. MTHFR c.665C>T polymorphism, leading to decreased MTHFR activity, is a potential pharmacogenomic marker for fluoropyrimidine drug response. The aim of the present study was to analyze the association of MTHFR c.665C>T polymorphism with fluoropyrimidine response in terms of therapy induced adverse events (AEs), requirement of dose reduction and delayed drug administration or therapy discontinuation. Methods The study group consisted of 313 fluoropyrimidine-treated cancer patients. PCR-RFLP was used to analyze MTHFR c.665C>T polymorphism. Results In female patients, MTHFR c.665 CT and TT genotypes were associated with dose reduction (p=0.029). In gender stratification, regression analysis adjusted for age of disease onset, body surface area and AE incidence, showed that MTHFR CT and TT genotypes increased both need for fluoropyrimidine dose reduction (OR 5.050, 95% CI 1.346–18.948, p=0.016) and percentage of dose reduction ( β =3.318, 95% C.I. 1.056–5.580, p=0.004) in female patients. Such differences were not present in male patients. No other associations were found. Conclusions MTHFR c.665C>T polymorphism was associated with fluoropyrimidine dose reduction in female cancer patients. This gender* MTHFR interaction merits further investigation.