Publications

2021
Leslie Rebibo, Connie Tam, Yan Sun, Eve Shoshani, Amit Badihi, Taher Nassar, and Simon Benita. 2021. “Topical tacrolimus nanocapsules eye drops for therapeutic effect enhancement in both anterior and posterior ocular inflammation models.” Journal of Controlled Release, 333, Pp. 283–297. Abstract
Tacrolimus has shown efficacy in eye inflammatory diseases. However, due to the drug lability, its formulation into a stable ophthalmic product remains a challenge. Tacrolimus-loaded nanocapsules (NCs) were designed for ocular instillation. Further, the stability and effects of the formulation were analyzed under different experimental conditions. Physicochemical characterization of the NCs revealed suitable homogeneous size and high encapsulation efficiency. Moreover, the lyophilized formulation was stable at ICH long term and accelerated storage conditions, for at least 18 and 3 months, respectively. The tacrolimus NCs did not elicit any eye irritation in rabbits after single- and multiple-dose applications. Additionally, ex vivo penetration assays on isolated porcine cornea and pharmacokinetics analyses in various rabbit eye compartments demonstrated the superiority of the NCs in retention and permeation into the anterior chamber of the eye compared to the free drug dissolved in oil. Moreover, multiple dose ocular instillation of the NCs in rats allowed high tacrolimus levels in the eye with very low plasma concentrations. Finally, the developed delivery system achieved a significant decrease in four typical inflammatory markers in a murine model of keratitis, an anterior chamber inflammation. Furthermore, these NCs, applied as eye drops, displayed clinical and histological efficacy in the mainly posterior chamber inflammation model of murine, experimental auto-immune uveitis.
Yuval Ramot, Michal Steiner, Netanel Amouyal, Yossi Lavie, Guy Klaiman, Abraham J. Domb, Abraham Nyska, and Tal Hagigit. 2021. “Treatment of contaminated radial fracture in sprague-dawley rats by application of a degradable polymer releasing gentamicin.” Journal of Toxicologic Pathology, 34, 1, Pp. 11–22. Abstract
Fracture-related infections remain a leading cause of morbidity and mortality. We aimed to establish a simple contaminated radial osteotomy model to assess the efficacy of a biodegradable polymer poly(sebacic-co-ricinoleic acid) [p(SA-RA)] containing 20% w/w gentamicin. A unilateral transverse osteotomy was induced in Sprague-Dawley (SD) rats, followed by application of Staphylococcus aureus suspension over the fracture. After successfully establishing the contaminated open fracture model, we treated the rats either systemically (intraperitoneal cefuroxime), locally with p(SA-RA) containing gentamicin, or both. Control groups included non-contaminated group and contaminated groups that were either untreated or treated with the polymer alone. After 4 weeks, the bones were subjected to micro-CT scanning and microbiological and histopathology evaluations. Micro-CT analysis revealed similar changes in the group subjected to both local and systemic treatment as in the non-contaminated control group. Lack of detectable bacterial growth was noted in most animals of the group subjected to both local and systemic treatment, and all samples were negative for S. aureus. Histopathological evaluation revealed that all treatment modalities containing antibiotics were highly effective in reducing infection and promoting callus repair, resulting in early bone healing. While p(SA-RA) containing gentamicin treatment showed better results than cefuroxime, the combination of local and systemic treatment displayed the highest therapeutic potential in this model.
Aparna Anand, Abhinay Sharma, Miriam Ravins, Debabrata Biswas, Poornima Ambalavanan, Kimberly Xuan Zhen Lim, Rachel Ying Min Tan, Atul Kumar Johri, Boaz Tirosh, and Emanuel Hanski. 2021. “Unfolded protein response inhibitors cure group A streptococcal necrotizing fasciitis by modulating host asparagine.” Science Translational Medicine, 13, 605, Pp. eabd7465. Abstract
Group A streptococcus (GAS) is among the top 10 causes of mortality from an infectious disease, producing mild to invasive life-threatening manifestations. Necrotizing fasciitis (NF) is characterized by a rapid GAS spread into fascial planes followed by extensive tissue destruction. Despite prompt treatments of antibiotic administration and tissue debridement, mortality from NF is still high. Moreover, there is no effective vaccine against GAS, and early diagnosis of NF is problematic because its clinical presentations are not specific. Thus, there is a genuine need for effective treatments against GAS NF. Previously, we reported that GAS induces endoplasmic reticulum (ER) stress to gain asparagine from the host. Here, we demonstrate that GAS-mediated asparagine induction and release occur through the PERK-eIF2$\alpha$-ATF4 branch of the unfolded protein response. Inhibitors of PERK or integrated stress response (ISR) blocked the formation and release of asparagine by infected mammalian cells, and exogenously added asparagine overcame this inhibition. Moreover, in a murine model of NF, we show that the inhibitors minimized mortality when mice were challenged with a lethal dose of GAS and reduced bacterial counts and lesion size when mice were challenged with a sublethal dose. Immunohistopathology studies demonstrated that PERK/ISR inhibitors protected mice by enabling neutrophil infiltration into GAS-infected fascia and reducing the pro-inflammatory response that causes tissue damage. Inhibitor treatment was also effective in mice when started at 12 hours after infection. We conclude that host metabolic alteration induced by PERK or ISR inhibitors is a promising therapeutic strategy to treat highly invasive GAS infections.
Roopesh Singh Gangwar, Hadas Pahima, Pier Giorgio Puzzovio, and Francesca Levi-Schaffer. 2021. “Update on Eosinophil Interaction with Mast Cells: The Allergic Effector Unit.” Methods in Molecular Biology, 2241, Pp. 221–242. Abstract
Mast cells and eosinophils are the key effector cells of allergy [1]. In general, allergic reactions are composed of two phases, namely an early phase and a late phase, and after that resolution occurs. If the allergic reactions fail to resolve after the late phase, allergic inflammation (AI) can evolve into a chronic phase mainly involving mast cells and eosinophils that abundantly coexist in the inflamed tissue in the late and chronic phases and cross-talk in a bidirectional manner. We defined these bidirectional interactions between MCs and Eos, as the “allergic effector unit.” This cross talk is mediated by both physical cell-cell contacts through cell surface receptors such as CD48, 2B4, and respective ligands and through released mediators such as various specific granular mediators, arachidonic acid metabolites, cytokines, and chemokines [2, 3]. The allergic effector unit can be studied in vitro in a customized co-culture system using mast cells and eosinophils derived from either mouse or human sources.
Ronit Vogt Sionov, Irith Gati, David Kirmayer, Michael Friedman, Doron Steinberg, and Menachem Gross. 2021. “Voice Prosthesis Coated with Sustained Release Varnish Containing Clotrimazole Shows Long-Term Protection against Candida albicans: An In Vitro Study.” Molecules (Basel, Switzerland), 26, 17. Abstract
Fungal biofilm formation on voice prosthesis (VP) is a major health problem that requires repeated replacement of the prosthesis. Candida albicans is one of the pathogens that frequently inhabits the VP. We proposed that coating VPs with sustained-release varnish (SRV) containing clotrimazole (CTZ) might prevent fungal biofilm formation. The long-term antifungal activities of SRV-CTZ- versus SRV-placebo-coated VPs was tested daily by measuring the inhibition zone of C. albicans seeded on agar plates or by measuring the fungal viability of C. albicans in suspension. The extent of biofilm formation on coated VPs was analyzed by confocal microscopy and scanning electron microscopy. We observed that SRV-CTZ-coated VPs formed a significant bacterial inhibition zone around the VPs and prevented the growth of C. albicans in suspension during the entire testing period of 60 days. Fungal biofilms were formed on placebo-coated VPs, while no significant biofilms were observed on SRV-CTZ-coated VPs. HPLC analysis shows that CTZ is continuously released during the whole test period of 60 days at a concentration above the minimal fungistatic concentration. In conclusion, coating VPs with an SRV-CTZ film is a potential effective method for prevention of fungal infections and biofilm formation on VPs.
2020
Benzion Amoyav, Yoel Goldstein, Eliana Steinberg, and Ofra Benny. 2020. “3D Printed Microfluidic Devices for Drug Release Assays.” Pharmaceutics, 13, 1. Abstract
Microfluidics research for various applications, including drug delivery, cell-based assays and biomedical research has grown exponentially. Despite this technology's enormous potential, drawbacks include the need for multistep fabrication, typically with lithography. We present a one-step fabrication process of a microfluidic chip for drug dissolution assays based on a 3D printing technology. Doxorubicin porous and non-porous microspheres, with a mean diameter of 250µm, were fabricated using a conventional "batch" or microfluidic method, based on an optimized solid-in-oil-in-water protocol. Microspheres fabricated with microfluidics system exhibited higher encapsulation efficiency and drug content as compared with batch formulations. We determined drug release profiles of microspheres in varying pH conditions using two distinct dissolution devices that differed in their mechanical barrier structures. The release profile of the "V" shape barrier was similar to that of the dialysis sac test and differed from the "basket" barrier design. Importantly, a cytotoxicity test confirmed biocompatibility of the printed resin. Finally, the chip exhibited high durability and stability, enabling multiple recycling sessions. We show how the combination of microfluidics and 3D printing can reduce costs and time, providing an efficient platform for particle production while offering a feasible cost-effective alternative to clean-room facility polydimethylsiloxane-based chip microfabrication.
Nadine Landolina, Ilan Zaffran, Dubravka Smiljkovic, Eva Serrano-Candelas, Dominik Schmiedel, Sheli Friedman, Michel Arock, Karin Hartmann, Eli Pikarsky, Ofer Mandelboim, Margarita Martin, Peter Valent, and Francesca Levi-Schaffer. 2020. “Activation of Siglec-7 results in inhibition of in vitro and in vivo growth of human mast cell leukemia cells.” Pharmacological research, 158, Pp. 104682. Abstract
Advanced systemic mastocytosis is a rare and still untreatable disease. Blocking antibodies against inhibitory receptors, also known as "immune checkpoints", have revolutionized anti-cancer treatment. Inhibitory receptors are expressed not only on normal immune cells, including mast cells but also on neoplastic cells. Whether activation of inhibitory receptors through monoclonal antibodies can lead to tumor growth inhibition remains mostly unknown. Here we show that the inhibitory receptor Siglec-7 is expressed by primary neoplastic mast cells in patients with systemic mastocytosis and by mast cell leukemia cell lines. Activation of Siglec-7 by anti-Siglec-7 monoclonal antibody caused phosphorylation of Src homology region 2 domain-containing phosphatase-1 (SHP-1), reduced phosphorylation of KIT and induced growth inhibition in mast cell lines. In SCID-beige mice injected with either the human mast cell line HMC-1.1 and HMC-1.2 or with Siglec-7 transduced B cell lymphoma cells, anti-Siglec-7 monoclonal antibody reduced tumor growth by a mechanism involving Siglec-7 cytoplasmic domains in "preventive" and "treatment" settings. These data demonstrate that activation of Siglec-7 on mast cell lines can inhibit their growth in vitro and in vivo. This might pave the way to additional treatment strategies for mastocytosis.
D Ferastraoaru, HJ Bax, C Bergmann, M Capron, M Castells, D Dombrowicz, E Fiebiger, HJ Gould, K Hartmann, U Jappe, G Jordakieva, DH Josephs, F Levi-Schaffer, V Mahler, A Poli, D Rosenstreich, F Roth-Walter, M Shamji, EH Steveling-Klein, MC Turner, E Untersmayr, SN Karagiannis, and E Jensen-Jarolim. 2020. “AllergoOncology: ultra-low IgE, a potential novel biomarker in cancer-a Position Paper of the European Academy of Allergy and Clinical Immunology (EAACI).” Clinical and translational allergy, 10, Pp. 32. Abstract
Elevated serum IgE levels are associated with allergic disorders, parasitosis and specific immunologic abnormalities. In addition, epidemiological and mechanistic evidence indicates an association between IgE-mediated immune surveillance and protection from tumour growth. Intriguingly, recent studies reveal a correlation between IgE deficiency and increased malignancy risk. This is the first review discussing IgE levels and links to pathological conditions, with special focus on the potential clinical significance of ultra-low serum IgE levels and risk of malignancy. In this Position Paper we discuss: (a) the utility of measuring total IgE levels in the management of allergies, parasitosis, and immunodeficiencies, (b) factors that may influence serum IgE levels, (c) IgE as a marker of different disorders, and d) the relationship between ultra-low IgE levels and malignancy susceptibility. While elevated serum IgE is generally associated with allergic/atopic conditions, very low or absent IgE may hamper anti-tumour surveillance, indicating the importance of a balanced IgE-mediated immune function. Ultra-low IgE may prove to be an unexpected biomarker for cancer risk. Nevertheless, given the early stage of investigations conducted mostly in patients with diseases that influence IgE levels, in-depth mechanistic studies and stratification of malignancy risk based on associated demographic, immunological and clinical co-factors are warranted.
P Gaur, P Kumar, A Sharma, and SK Lal. 2020. “AML1 protein interacts with influenza A virus neuraminidase and upregulates IFN-$\beta$ response in infected mammalian cells.” Letters in applied microbiology, 70, 4, Pp. 252–258. Abstract
Neuraminidase (NA) is an integral membrane protein of influenza A virus (IAV) and primarily aids in the release of progeny virions, following the intracellular viral replication cycle. In an attempt to discover new functions of NA, we conducted a classical yeast two-hybrid screen and found acute myeloid leukaemia marker 1 (AML1) as a novel interacting partner of IAV-NA. The interaction was further validated by co-immunoprecipitation in IAV-infected cells and in an in vitro coupled transcription/translation system. Interestingly, we found an increase in the expression of AML1 upon IAV infection in a dose-dependent manner. As expected, we also observed an increase in the IFN-$\beta$ levels, the first line of defence against viral infections. Subsequently, when AML1 was downregulated using siRNA, the IFN-$\beta$ levels were found to be remarkably reduced. Our study also shows that AML1 is induced upon IAV infection and results in the induction of IFN-$\beta$. Thus, AML1 is proposed to be an important player in IFN induction and has a role in an antiviral response against IAV infection. SIGNIFICANCE AND IMPACT OF THE STUDY: Influenza epidemics and pandemics are constant threats to human health. Development of antiviral therapeutics has focused on important and major IAV proteins as targets. However, the rate at which this virus mutates makes the task challenging. Thus, next-generation approaches aim at host cellular proteins that aid the virus in its replication. This study reports a new host-virus interaction, of acute myeloid leukaemia marker 1 (AML1) with influenza A neuraminidase (IAV-NA). We have found that this interaction has a direct effect on the upregulation of host IFN-$\beta$ response. Further studies may lead to a greater understanding of this new innate defence pathway in infected cells.
Rhoda Olowe, Sereen Sandouka, Aseel Saadi, and Tawfeeq Shekh‐ahmad. 2020. “Approaches for reactive oxygen species and oxidative stress quantification in epilepsy.” Antioxidants, 9, 10, Pp. 1–26. Abstract
Oxidative stress (OS) and excessive reactive oxygen species (ROS) production have been implicated in many neurological pathologies, including acute seizures and epilepsy. Seizure-induced damage has been demonstrated both in vitro and in several in vivo seizure and epilepsy models by direct determination of ROS, and by measuring indirect markers of OS. In this manuscript, we review the current reliable methods for quantifying ROS‐related and OS‐related markers in pre‐clinical and clinical epilepsy studies. We first provide pieces of evidence for the involvement of different sources of ROS in epilepsy. We then discuss general methods and assays used for the ROS measurements, mainly superoxide anion, hydrogen peroxide, peroxynitrite, and hydroxyl radical in in vitro and in vivo studies. In addition, we discuss the role of these ROS and markers of oxidative injury in acute seizures and epilepsy pre‐clinical studies. The indirect detection of secondary products of ROS such as measurements of DNA damage, lipid peroxidation, and protein oxidation will also be discussed. This review also discusses reliable methods for the assessment of ROS, OS markers, and their by‐products in epilepsy clinical studies.
Francesca Forno, Yossi Maatuf, Shatha Boukeileh, Priya Dipta, Mohamed Mahameed, Odai Darawshi, Vitor Ferreira, Patricia Rada, Irma García-Martinez, Einav Gross, Avi Priel, Ángela M Valverde, and Boaz Tirosh. 2020. “Aripiprazole Cytotoxicity Coincides with Activation of the Unfolded Protein Response in Human Hepatic Cells.” The Journal of pharmacology and experimental therapeutics, 374, 3, Pp. 452–461. Abstract
Schizophrenia is a mental disease that results in decreased life expectancy and well-being by promoting obesity and sedentary lifestyles. Schizophrenia is treated by antipsychotic drugs. Although the second-generation antipsychotics (SGA), Olanzapine and Aripiprazole, are more effective in treating schizophrenia, they display a higher risk of metabolic side effects, mostly by development of diabetes and insulin resistance, weight gain, and dyslipidemia. Endoplasmic reticulum (ER) stress is induced when ER homeostasis of lipid biosynthesis and protein folding is impaired. This leads to the activation of the unfolded protein response (UPR), a signaling cascade that aims to restore ER homeostasis or initiate cell death. Chronic conditions of ER stress in the liver are associated with diabetes and perturbed lipid metabolism. These metabolic dysfunctions resemble the pharmacological side effects of SGAs. We therefore investigated whether SGAs promote the UPR in human and mouse hepatocytes. We observed full-fledged activation of ER stress by Aripiprazole not by Olanzapine. This occurred at low micromolar concentrations and to variable intensities in different cell types, such as hepatocellular carcinoma, melanoma, and glioblastoma. Mechanistically, Aripiprazole caused depletion of ER calcium, leading to activation of inositol-requiring enzyme 1 (IRE1)and protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK), two major transducers of the UPR. Cells underwent apoptosis with Aripiprazole treatment, which coincided with UPR induction, and this effect was reduced by adding glutathione without affecting UPR itself. Deletion of IRE1 from HepG2, a human liver cancer cell line, protected cells from Aripiprazole toxicity. Our study reveals for the first time a cytotoxic effect of Aripiprazole that involves the induction of ER stress. SIGNIFICANCE STATEMENT: The antischizophrenic drug Aripiprazole exerts cytotoxic properties at high concentrations. This study shows that this cytotoxicity is associated with the induction of endoplasmic reticulum (ER) stress and IRE1 activation, mechanisms involved in diet-induced obesity. Aripiprazole induced ER stress and calcium mobilization from the ER in human and mouse hepatocytes. Our study highlights a new mechanism of Aripiprazole that is not related to its effect on dopamine signaling.
Chen Belay, Noam Y Steinman, Luis M Campos, Ron Dzikowski, Jacob Golenser, and Abraham J Domb. 2020. “Asymmetric trisalkylamine cyclopropenium derivatives with antimicrobial activity.” Bioorganic chemistry, 102, Pp. 104069. Abstract
Cationic molecules are found in abundance as antimicrobial agents with a well-defined mechanism of action and significant therapeutic benefits. Quaternary ammonium-containing compounds are frequently employed due to their facile synthesis and tunable properties. Over time, however, bacterial resistance to these compounds has become a significant obstacle. We report here a series of asymmetric trisalkylamine cyclopropenium cationic derivatives as chemical isosteres of quaternary ammonium compounds, capable of strong antimicrobial activity and overcoming microbial resistance. These small molecules were prepared by one-pot reaction of tetrachlorocyclopropene (TCC) with unhindered secondary amines in the presence of Hünig's base. In this work we describe the synthesis, purification, and characterization of five trisamino-cyclopropenium derivatives and confirm their structures by spectral analysis and mass-spectrometry. Three of the compounds displayed considerable antimalarial activity (IC(50) < 0.1 µM) without demonstrating significant toxic effects in vitro (TC(50) > 1 µM). This class of cyclopropenium-based compounds provides an opening for the discovery of potent and non-toxic antimicrobial agents.
Michal Eger, Miaad Bader, Dara Bree, Rivka Hadar, Alina Nemirovski, Joseph Tam, Dan Levy, Chaim G Pick, and Yankel Gabet. 2020. “Author Correction: Bone Anabolic Response in the Calvaria Following Mild Traumatic Brain Injury is Mediated by the Cannabinoid-1 Receptor.”. Abstract
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Moran Haim Zada, Zehava Gallimidi, Michal Schlesinger Laufer, Abraham Nyska, and Abraham J Domb. 2020. “Biodegradable Breast Tissue Marker Clip.” ACS applied bio materials, 3, 11, Pp. 7439–7453. Abstract
Biodegradable soft tissue biopsy clips have been developed as implants with the potential to serve as visual markers for regions suspected to contain tumor growth in the breast. These clips are multidimensional tissue markers with better biocompatibility and imaging features. The clips were prepared using biodegradable polymers, poly(l-lactide-co-$ε$-caprolactone) and methoxy polyethylene glycol-co-l-lactide, that contain iodixanol or barium sulfate as contrast agents; they are further coated with hyaluronic acid or sodium alginate hydrogels. The clips were visible by imaging modalities such as mammography, ultrasound, and magnetic resonance imaging after implantation in Sprague-Dawley rats. The clips stayed intact in the implantation cavity of the animal for more than 3 months with unpretentious changes in their lengths and morphology. The histopathological examination of implanted clips revealed no signs of systemic toxicity in the rats. Overall, the interpretation of the results reveals that the developed clips can be a potential replacement for metal-based markers.
Natalie Filippov-Levy, Reuven Reich, and Ben Davidson. 2020. “The Biological and Clinical Role of the Long Non-Coding RNA LOC642852 in Ovarian Carcinoma.” International journal of molecular sciences, 21, 15. Abstract
The objective of the present study was to analyze the biological and clinical role of the long non-coding RNA LOC642852 in ovarian carcinoma (OC). LOC642852 expression was analyzed in seven OC cell lines (OVCAR-3, OVCAR-8, OVCA 433, OVCA 429, OC 238, DOV13, ES-2) and 139 high-grade serous carcinoma (HGSC) specimens (85 effusions, 54 surgical specimens). Following LOC642852 knockout (KO) using the CRISPR/Cas9 system, OVCAR-8 HGSC cells were analyzed for spheroid formation, migration, invasion, proliferation, matrix metalloproteinase (MMP) activity, and expression of cell signaling proteins. OVCAR-8 cells with LOC642852 KO were significantly less motile and less invasive compared to controls, with no differences in spheroid formation, proliferation, or matrix metalloproteinase (MMP) activity. Total Akt and Erk levels were comparable in controls and KO cells, but their phosphorylation was significantly increased in the latter. In clinical specimens, LOC642852 was overexpressed in ovarian tumors and omental/peritoneal metastases compared to effusion specimens (p = 0.013). A non-significant trend for shorter overall (p = 0.109) and progression-free (p = 0.056) survival was observed in patients with HGSC effusions with high LOC642852 levels. Bioinformatics analysis showed potential roles for LOC642852 as part of the TLE3/miR-221-3p ceRNA network and in relation to the FGFR3 protein. In conclusion, LOC642852 inactivation via CRISPR/Cas9 affects cell signaling, motility, and invasion in HGSC cells. LOC642852 is differentially expressed in HGSC cells at different anatomical sites. Its potential role in regulating the TLE3/miR-221-3p ceRNA network and FGFR3 merits further research.
Natalie Filippov-Levy, Ben Davidson, and Reuven Reich. 2020. “The Biological Role of the Long Non-coding RNA LINK-A in Ovarian Carcinoma.” Anticancer Research, 40, 12, Pp. 6677–6684. Abstract
Aim: To analyze the biological role of the long non-coding RNA LINK-A. Materials and Methods: An 850-bp segment from the second exon of LINK-A was removed using the CRISPR/Cas9 system in OVCA433 ovarian serous carcinoma cells. Spheroid formation, migration, invasion, proliferation, matrix metalloproteinase (MMP) activity and expression of cell-signaling proteins were assessed in vitro. Results: OVCA433 cells with LINK-A deletion were more invasive (p=0.0008) but had reduced migration and MMP9 secretion compared to controls (p=0.003 and p=0.005, respectively). LINK-A deletion did not affect proliferation but induced phosphorylation of extracellular signal-regulated kinase (10-fold; p=0.005). LINK-A knock out additionally reduced spheroid formation. Conclusion: Added to our previous data from analysis of clinical specimens, LINK-A is likely to be a tumor suppressor.
Einat Gorelik, Boris Gorelik, Reem Masarwa, Amichai Perlman, Bruria Hirsh-Raccah, and Ilan Matok. 2020. “The cardiovascular safety of antiobesity drugs-analysis of signals in the FDA Adverse Event Report System Database.” International journal of obesity (2005), 44, 5, Pp. 1021–1027. Abstract
AIMS: Over the past several decades, many antiobesity drugs have been withdrawn from the market due to unanticipated adverse events, often involving cardiotoxicity. This study aimed to evaluate the presence of cardiovascular safety signals with currently marketed antiobesity drugs. METHODS: We used the US Food and Drug Administration Adverse Event Reporting System (FAERS) database and retrieved data from January 2013 through December 2018. We performed disproportionality analyses to detect cardiovascular safety signals with three antiobesity drugs recently approved for marketing: lorcaserin, naltrexone-bupropion, phentermine, and phentermine-topiramate. Three main cardiovascular outcomes were evaluated: valvular disorders, and pulmonary hypertension (PH) and other cardiovascular events (myocardial infarction, stroke, cardiovascular death, cardiac failure, and arrhythmia). RESULTS: During the evaluated period, a total of 6,787,840 adverse event reports were submitted to FAERS. Of these, 2687 involved lorcaserin, 3960 involved phentermine/phentermine-topiramate, and 2873 involved naltrexone-bupropion. Lorcaserin was associated with a significantly greater proportion of reports of valvular disorders (ROR = 4.39; 95% CI 2.72-5.07). None of the antiobesity drugs were associated with a safety signal for valvulopathy, PH, or other cardiovascular events. CONCLUSIONS: Our analyses revealed a signal for valvular disorders with lorcaserin and did not detect a safety signal for other cardiovascular events with recently approved antiobesity drugs. Further research is needed to explore and validate this signal.
Sarah Israel, Hila Elinav, Ram Elazary, Daniel Porat, Roni Gibori, Arik Dahan, Carmil Azran, and Ehud Horwitz. 2020. “Case Report of Increased Exposure to Antiretrovirals following Sleeve Gastrectomy.” Antimicrobial agents and chemotherapy, 64, 4. Abstract
Bariatric surgery is increasingly performed in morbidly obese HIV patients. Limited data exist regarding antiretroviral drug exposure after bariatric surgery. We report a case of a morbidly obese HIV patient who underwent sleeve gastrectomy. Abacavir, lamivudine, and dolutegravir therapeutic drug monitoring was performed at several time points pre- and postsurgery. Significantly increased levels were measured, particularly for abacavir, whose levels increased ∼12-fold. Several mechanistic explanations for these findings are discussed.
Adi Drori, Asaad Gammal, Shahar Azar, Liad Hinden, Rivka Hadar, Daniel Wesley, Alina Nemirovski, Gergő Szanda, Maayan Salton, Boaz Tirosh, and Joseph Tam. 2020. “Cb1r regulates soluble leptin receptor levels via chop, contributing to hepatic leptin resistance.” eLife, 9, Pp. 1–26. Abstract
The soluble isoform of leptin receptor (sOb-R), secreted by the liver, regulates leptin bioavailability and bioactivity. Its reduced levels in diet-induced obesity (DIO) contribute to hyperleptinemia and leptin resistance, effects that are regulated by the endocannabinoid (eCB)/ CB1R system. Here we show that pharmacological activation/blockade and genetic overexpression/ deletion of hepatic CB1 R modulates sOb-R levels and hepatic leptin resistance. Interestingly, peripheral CB1 R blockade failed to reverse DIO-induced reduction of sOb-R levels, increased fat mass and dyslipidemia, and hepatic steatosis in mice lacking C/EBP homologous protein (CHOP), whereas direct activation of CB1 R in wild-type hepatocytes reduced sOb-R levels in a CHOP-dependent manner. Moreover, CHOP stimulation increased sOb-R expression and release via a direct regulation of its promoter, while CHOP deletion reduced leptin sensitivity. Our findings highlight a novel molecular aspect by which the hepatic eCB/CB1R system is involved in the development of hepatic leptin resistance and in the regulation of sOb-R levels via CHOP.
Philip Lazarovici, Cezary Marcinkiewicz, and Peter I Lelkes. 2020. “Cell-Based Adhesion Assays for Isolation of Snake Venom's Integrin Antagonists.” Methods in molecular biology (Clifton, N.J.), 2068, Pp. 205–223. Abstract
Snake venoms could lead to the development of new drugs to treat a range of life-threatening conditions like cardiovascular diseases. Most snake venoms contain a large variety of lethal toxins as well as anti-adhesive proteins such as disintegrins, which have evolved from the harmless compounds ADAMs (proteins with a disintegrin and a metalloprotease domain) and C-type lectin proteins which disturb connective tissue and cell-matrix interaction. These anti-adhesive proteins target and block integrin receptors and disrupt normal biological processes in snakes' prey such as connective tissue physiology and blood clotting. This chapter provides the experimental details of a practical, cell-based adhesion protocol to help identify and isolate disintegrins and C-type lectin proteins from snake venoms, important tools in integrin research and lead compounds for drug discovery.