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Hana Polachek,1,* Nir Debotton,2,* Valeria Feinshtein,1 Mazal Rubin,1 Zvi Ben-Zvi,1,‡ Gershon Holcberg,3 Riad Agbaria,1 Arik Dahan1 1Department of Clinical Pharmacology, School of Pharmacy, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel; 2Department of Chemical Engineering, Shenkar College of Engineering and Design, Ramat-Gan, Israel; 3Division of Obstetrics and Gynecology, Soroka University Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel *These authors contributed equally to this work ‡Professor Zvi Ben-Zvi passed away on August 4, 2017 Introduction: Six years after the US Food and Drug Administration approval of the broad-spectrum antibiotic ofloxacin (OFLX), the chiral switching of this racemic mixture resulted in a drug composed of the l-optical isomer levofloxacin (LVFX). Since both fluoroquinolones (FQs) were introduced to the pharmaceutical market, they have been widely prescribed by physicians, with careful administration during pregnancy and breastfeeding. Therefore, the role of the influx and efflux placental transporters in the concentrations of these drugs that permeate through human placental barrier model was investigated in this study. Methods: The contribution of major carriers on the transplacental flux of OFLX and LVFX uptake into choriocarcinoma BeWo cells was evaluated in the presence vs absence of well-known inhibitors. Results: Our results reveal that neither the influx transporters such as organic cation transporters, organic anion transporters, and monocarboxylate transporters nor the efflux transporters such as P-glycoprotein or breast cancer resistance protein significantly affected the transport of OFLX. In contrast, multiple transporters revealed pronounced involvement in the transfer of the levorotatory enantiomer in and out of the invitro placental barrier. These data suggest a non-carrier-mediated mechanism of transport of the racemic mixture, while LVFX is subjected to major influx and efflux passage through the placental brush border membranes. Conclusion: This study provides underlying insights to elucidate the governing factors that influence the flux of these FQs through organ barriers, in view of the controversial safety profile of these drugs in pregnant population. Keywords: drug transport, fluoroquinolones, levofloxacin, ofloxacin, placenta, pregnancy

Riad Agbaria, Adi Gabarin, Arik Dahan, Shimon Ben-Shabat Department of Clinical Pharmacology, School of Pharmacy, Faculty of Health Sciences, Ben-Gurion University ofthe Negev, Beer-Sheva, Israel Abstract: The traditional preparation process of Nigella sativa (NS) oil starts with roasting of the seeds, an allegedly unnecessary step that was never skipped. The aims of this study were to investigate the role and boundaries of thermal processing of NS seeds in the preparation of therapeutic extracts and to elucidate the underlying mechanism. NS extracts obtained by various seed thermal processing methods were investigated in vitro for their antiproliferative activity in mouse colon carcinoma (MC38) cells and for their thymoquinone content. The effect of the different methods of thermal processing on the ability of the obtained NS oil to inhibit the nuclear factor kappa B (NF-κB) pathway was then investigated in Hodgkin’s lymphoma (L428) cells. The different thermal processing protocols yielded three distinct patterns: heating the NS seeds to 50°C, 100°C, or 150°C produced oil with a strong ability to inhibit tumor cell growth; no heating or heating to 25°C had a mild antiproliferative effect; and heating to 200°C or 250°C had no effect. Similar patterns were obtained for the thymoquinone content of the corresponding oils, which showed an excellent correlation with the antiproliferative data. It is proposed that there is an oxidative transition mechanism between quinones after controlled thermal processing of the seeds. While NS oil from heated seeds delayed the expression of NF-κB transcription, non-heated seeds resulted in only 50% inhibition. The data indicate that controlled thermal processing of NS seeds (at 50°C–150°C) produces significantly higher anticancer activity associated with a higher thymoquinone oil content, and inhibits the NF-κB signaling pathway. Keywords: Nigella sativa, thermal processing, antiproliferative effect, thymoquinone, NF-κB

Omri Wolk, Riad Agbaria, Arik Dahan Department of Clinical Pharmacology, School of Pharmacy, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel Abstract: The main objective of this work was to investigate in-silico predictions of physicochemical properties, in order to guide oral drug development by provisional biopharmaceutics classification system (BCS). Four in-silico methods were used to estimate LogP: group contribution (CLogP) using two different software programs, atom contribution (ALogP), and element contribution (KLogP). The correlations (r2) of CLogP, ALogP and KLogP versus measured LogP data were 0.97, 0.82, and 0.71, respectively. The classification of drugs with reported intestinal permeability in humans was correct for 64.3%–72.4% of the 29 drugs on the dataset, and for 81.82%–90.91% of the 22 drugs that are passively absorbed using the different in-silico algorithms. Similar permeability classification was obtained with the various in-silico methods. The in-silico calculations, along with experimental melting points, were then incorporated into a thermodynamic equation for solubility estimations that largely matched the reference solubility values. It was revealed that the effect of melting point on the solubility is minor compared to the partition coefficient, and an average melting point (162.7°C) could replace the experimental values, with similar results. The in-silico methods classified 20.76% (±3.07%) as Class 1, 41.51% (±3.32%) as Class 2, 30.49% (±4.47%) as Class 3, and 6.27% (±4.39%) as Class 4. In conclusion, in-silico methods can be used for BCS classification of drugs in early development, from merely their molecular formula and without foreknowledge of their chemical structure, which will allow for the improved selection, engineering, and developability of candidates. These in-silico methods could enhance success rates, reduce costs, and accelerate oral drug products development. Keywords: biopharmaceutics classification system, in-silico, intestinal permeability, partition coefficient, solubility