2022
Riccardo Serra, Mangraviti, Antonella , Gorelick, Noah L, Shapira-Furman, Tovi , Alomari, Safwan , Cecia, Arba , Darjee, Namrata , Brem, Henry , Rottenberg, Yakir , Domb, Abraham J, ו Tyler, Betty . 2022.
“Combined Intracranial Acriflavine, Temozolomide And Radiation Extends Survival In A Rat Glioma Model.”. European Journal Of Pharmaceutics And Biopharmaceutics : Official Journal Of Arbeitsgemeinschaft Fur Pharmazeutische Verfahrenstechnik E.v, 170, Pp. 179–186. doi:10.1016/j.ejpb.2021.12.011.
תקציר Glioblastomas have been historically difficult to treat with poor long-term survival. With novel strategies focused on targeting hypoxia-inducible factor (HIF) regulatory pathways, recent evidence has shown that Acriflavine (ACF) can effectively target glioma invasiveness and recurrence. However, local delivery of ACF and its combinatory effects with Temozolomide (TMZ) and radiation therapy (XRT) have not yet been optimized. In this study we test a novel polymeric matrix that can gradually release ACF at the tumor bed site in combination with systemic TMZ and XRT. In vitro cytotoxicity assays of ACF in combination with TMZ and XRT were performed on rodent and human cell lines with CCK-8 and flow cytometry. In vitro drug release was measured and intracranial safety was assessed in tumor-free animals. Finally, efficacy was assessed in an intracranial gliosarcoma model and combination therapy with TMZ and XRT evaluated. Combination therapy of ACF, TMZ, and XRT was able to reduce cell viability and induce apoptosis in glioma cells. In vitro and in vivo release of ACF was measured in benchtop and animal models. Efficacy was established in an in vivo gliosarcoma model in which intracranial ACF (p < 0.01) significantly improved median survival and the combination therapy of ACF, TMZ and XRT (p < 0.01) significantly improved median survival and led to long-term survival (LTS). We provide evidence that ACF, combined with TMZ and XRT, led to LTS in an intracranial model of rat gliosarcoma. These findings, in combination with the use of a novel polymeric matrix that allows more gradual drug delivery, constitute a first step in the translation of this novel strategy to human use.
Pier Giorgio Puzzovio, Brüggemann, Thayse R, Pahima, Hadas , Mankuta, David , Levy, Bruce D, ו Levi-Schaffer, Francesca . 2022.
“Cromolyn Sodium Differentially Regulates Human Mast Cell And Mouse Leukocyte Responses To Control Allergic Inflammation.”. Pharmacological Research, Pp. 106172. doi:10.1016/j.phrs.2022.106172.
תקציר BACKGROUND: Cromolyn Sodium (CS) has been used in the past as an anti-allergy drug owing to its mast cell (MC) stabilizing properties that impair histamine release. However, additional mechanisms for its clinical actions are likely and might help to identify new roles for MCs and leukocytes in regulating inflammation. Here, using human cord blood-derived MCs (CBMCs), murine bone marrow-derived MCs (BMMCs) and eosinophils (BMEos), and in vivo mouse models of allergic inflammation (AI), additional actions of CS on MCs were determined. METHODS: The in vitro effects of CS on IgE-activated human and mouse MCs were assessed by measuring the levels of pro-inflammatory (tryptase, LTC(4), IL-8, CD48) and pro-resolution effectors (IL-10, CD300a, Annexin A1) before and after CS treatment. The in vivo effects of daily CS injections on parameters of inflammation were assessed using mouse models of allergic peritonitis (AP) (Ovalbumin/Alum- or Ovalbumin/S. aureus enterotoxin B) and allergic airways inflammation (AAI) (house dust mite (HDM)). RESULTS: In vitro, CS did not affect pro-inflammatory effectors but significantly increased the anti-inflammatory/pro-resolution CD300a levels and IL-10 release from IgE-activated CBMCs. BMMCs were not affected by CS. In vivo, CS injections decreased total cell and Eos numbers in the peritoneal cavity in the AP models and bronchoalveolar lavage and lungs in the AAI model. CS reduced EPX release from PAF-activated BMEos in vitro, possibly explaining the in vivo findings. CONCLUSION: Together, these results demonstrate immunomodulatory actions for CS in AI that are broader than only MC stabilization.
Yizhou Jiang, Rubin, Limor , Peng, Tangming , Liu, Linlin , Xing, Xingan , Lazarovici, Philip , ו Zheng, Wenhua . 2022.
“Cytokine Storm In Covid-19: From Viral Infection To Immune Responses, Diagnosis And Therapy.”. International Journal Of Biological Sciences, 18, 2, Pp. 459–472. doi:10.7150/ijbs.59272.
תקציר The COVID-19 outbreak is emerging as a significant public health challenge. Excessive production of proinflammatory cytokines, also known as cytokine storm, is a severe clinical syndrome known to develop as a complication of infectious or inflammatory diseases. Clinical evidence suggests that the occurrence of cytokine storm in severe acute respiratory syndrome secondary to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is closely associated with the rapid deterioration and high mortality of severe cases. In this review, we aim to summarize the mechanism of SARS-CoV-2 infection and the subsequent immunological events related to excessive cytokine production and inflammatory responses associated with ACE2-AngII signaling. An overview of the diagnosis and an update on current therapeutic regimens and vaccinations is also provided.
Balakrishnan Solaimuthu, Lichtenstein, Michal , Hayashi, Arata , Khatib, Anees , Plaschkes, Inbar , Nevo, Yuval , Tanna, Mayur , Lavi, Shirel , Pines, Ophry , ו Shaul, Yoav D.. 2022.
“Depletion Of Fh, An Essential Tca Cycle Enzyme, Drives Proliferation In A Two-Step Model”. Biorxiv, Pp. 2022.06.16.496410.
תקציר Several tumor suppressor genes do not follow the canonical function of cell cycle repressors. For example, fumarate hydratase (FH) is an evolutionary conserved TCA cycle enzyme that reversibly catalyzes the hydration of fumarate to L-malate and has a moonlight function in the DNA damage response (DDR). Interestingly, despite this enzyme’s essential role in central carbon metabolism, FH is inactive or absent in several tumors, such as hereditary leiomyomatosis and renal cell cancer (HLRCC). Accordingly, FH has a contradictory cellular function, as it is pro-survival through its role in the TCA cycle, yet its loss can drive tumorigenesis. These observations have supported the role of FH as a tumor suppressor. Here, we solved this contradiction by determining the molecular mechanisms that allow the cells to survive and even proliferate upon FH loss. We found that the cells’ response to FH loss is separated into two distinct time frames based on cell proliferation and DNA damage repair. During the early stages of FH loss, the cells’ proliferation and DNA damage repair are inhibited. However, over time the cells overcome the FH loss and form knockout clones, indistinguishable from WT cells in their proliferation rate. Due to the FH loss effect on DNA damage repair, we assumed that the recovered cells bear adaptive mutations. Therefore, we applied whole-exome sequencing to identify such mutated genes systematically. Indeed, we identified recurring mutations in genes belonging to the central oncogenic signaling pathways, such as JAK/STAT, which we validated to be impaired in FH-KO clones. Intriguingly, we demonstrated that these adaptive mutations are responsible for FH-KO cell proliferation under TCA cycle malfunction.Competing Interest StatementThe authors have declared no competing interest.
תקציר
"השאלה היהודית לא תיפתר בעיניה של גרמניה גם אם לא יֵשב עוד איש מבני הגזע היהודי על אדמת גרמניה", כתב ב-1937 בכיר במשרד החוץ של גרמניה הנאצית, והוסיף: "השאלה היהודית היא מן השאלות החשובות ביותר של מדיניות החוץ של גרמניה".
שני מוקדים עומדים במרכזו של ספר זה: תולדות יהודי גרמניה בשואה ומעורבותו של משרד החוץ של גרמניה הנאצית. בשונה מקהילות אחרות חוותה יהדות גרמניה את הרייך השלישי בכל שנות קיומו. הדרך ל"פתרון בעיית היהודים הגרמנים" הייתה רצופה שלבים של הסלמה. 175 מסמכים שנכתבו על ידי הדיפלומטים של גרמניה הנאצית או מוענו אליהם מתורגמים כאן ומוצבים בסיפור ההיסטורי. המסמכים נוגעים בתהליכים שראשיתם בנישולם האזרחי והכלכלי של יהודי גרמניה ובכפיית ההגירה, והמשכם בגירושים ובהשמדה, בתגובותיהם של היהודים הגרמנים, בתגובות שהגיעו מחוץ לגרמניה ובתפקידו של משרד החוץ, בתוקף מיומנותו הייחודית, בהצגה לעולם של הצעדים שנקטה גרמניה כנגד אזרחיה היהודים.
במערך הכולל של עובדי הציבור ברייך השלישי ששירתו את רעיונותיו והביאו להגשמתם לקחו הדיפלומטים חלק – לעתים באדישות ולעתים בלהט – בתהליכי "הפתרון הסופי", תחילה בעבודות ההכנה ולאחר מכן בשיתוף פעולה עם המוציאים לפועל הלכה למעשה.
"אף שמדובר בהיסטוריה של מוסד, משרד ממשלתי, פורטת המחברת את הסיפור לסיפורם של אנשים. הדיפלומטים, שרובם נמנו עם הפושעים, יוצאים מאלמוניותם, והפרטים הרלוונטיים המוזכרים בטקסט הופכים אותם לדמויות חיות, אנשים שביקשו לקדם את הקריירה שלהם, למדו לחיות עם מערכת מוסר חדשה ולעצום עיניים לעוולות". (פרופ' משה צימרמן)
Synopsis
Two focal points are at the center of this book: the history of German Jews during the Holocaust and the involvement of the Foreign Ministry of Nazi Germany. The process of "solving the problem of the German Jews" consisted of stages of escalation that are exemplified in 175 translated documents written by or addressed to German diplomats. The narrative that is placed in the historical context, demonstrates the course that began with the deprivation and dispossession of German Jews of their civil and economic rights, continues with their forced immigration and finally with their deportation and extermination. Included are the reactions of the German Jews, the responses that came from outside Germany, and the role of the Foreign Ministry, who was eager to participate in “solving the Jewish Question”. The book opens with a preface by Prof. Moshe Zimmermann.
This book collects rewritten articles and essays by the author related first and foremost, but not exclusively, to the catastrophe of the Holocaust as an epistemic crisis – qualified as a “rupture in civilization”, i.e. the destruction of concepts deeply rooted in a common anthropology of humankind, while focusing on methodological as well as conceptual questions.
The composition of the volume runs roughly chronologically along several layers of interpretation – embracing questions of German constitutional law, the formation of Continental expansionist geopolitical thinking, the epistemology of the Holocaust, the assertion and transformation of paradigms of historical interpretation in the second half of the 20th century, especially the turn from social history to memory studies, as well as the turn from a Western- and Eurocentric approaches into the direction of colonial and global history.
To combat the various DNA lesions and their harmful effects, cells have evolved different strategies, collectively referred as DNA damage response (DDR). The DDR largely relies on intranuclear protein networks, which sense DNA lesions, recruit DNA repair enzymes, and coordinates several aspects of the cellular response, including a temporary cell cycle arrest. In addition, external cues mediated by the surface EGF receptor (EGFR) through downstream signaling pathways contribute to the cellular DNA repair capacity. However, cell cycle progression driven by EGFR activation should be reconciled with cell cycle arrest necessary for effective DNA repair. Here, we show that in damaged cells, the expression of Mig-6 (mitogen-inducible gene 6), a known regulator of EGFR signaling, is reduced resulting in heightened EGFR phosphorylation and downstream signaling. These changes in Mig-6 expression and EGFR signaling do not occur in cells deficient of Mre-11, a component of the MRN complex, playing a central role in double-strand break (DSB) repair or when cells are treated with the MRN inhibitor, mirin. RNAseq and functional analysis reveal that DNA damage induces a shift in cell response to EGFR triggering that potentiates DDR-induced p53 pathway and cell cycle arrest. These data demonstrate that the cellular response to EGFR triggering is skewed by components of the DDR, thus providing a plausible explanation for the paradox of the known role played by a growth factor such as EGFR in the DNA damage repair.
Leslie Rebibo, Frušić-Zlotkin, Marina , Ofri, Ron , Nassar, Taher , ו Benita, Simon . 2022.
“The Dose-Dependent Effect Of A Stabilized Cannabidiol Nanoemulsion On Ocular Surface Inflammation And Intraocular Pressure.”. International Journal Of Pharmaceutics, 617, Pp. 121627. doi:10.1016/j.ijpharm.2022.121627.
תקציר Cannabidiol (CBD) is a phytocannabinoid that has a great clinical therapeutic potential. Few studies have been published on its efficacy in ocular inflammations while its impact on intraocular pressure (IOP), a major risk factor for glaucoma, remains unclear. Moreover, due to its lability and high lipophilicity, its formulation within a prolonged stable topical ophthalmic solution or emulsion able to penetrate the highly selective corneal barrier is challenging. Therefore, various CBD nanoemulsions (NEs) were designed and evaluated for stability in accelerated conditions. Further, the optimal formulation was tested on a murine LPS-induced keratitis inflammation model. Lastly, increasing CBD concentrations were topically applied, for two weeks, on mice eyes, for IOP measurement. CBD NEs exhibited optimal physicochemical characteristics for ocular delivery. A specific antioxidant was required to obtain the stable, final, formulation. In vivo, 0.4 to 1.6% CBD w/v reduced the levels of key inflammatory cytokines, depending on the concentration applied. These concentrations decreased or did not affect the IOP. Our results showed that a well-designed CBD ocular dosage form can be stabilized for an extended shelf life. Furthermore, the significant decrease in inflammatory cytokines levels could be exploited, provided that an adequate therapeutic dosage regimen is identified in humans.
Reem Smoum, Haj, Christeene , Shira Hirsch, , Nemirovski, Alina , Yekhtin, Zhannah , Bogoslavsky, Benny , Bakshi, Gaganjyot Kaur , Chourasia, Mukesh , Gallily, Ruth , Tam, Joseph , ו Raphael Mechoulam, . 2022.
“Fenchone Derivatives As A Novel Class Of Cb2 Selective Ligands: Design, Synthesis, X-Ray Structure And Therapeutic Potential.”. Molecules (Basel, Switzerland), 27, 4. doi:10.3390/molecules27041382.
תקציר A series of novel cannabinoid-type derivatives were synthesized by the coupling of (1S,4R)-(+) and (1R,4S)-(-)-fenchones with various resorcinols/phenols. The fenchone-resorcinol derivatives were fluorinated using Selectfluor and demethylated using sodium ethanethiolate in dimethylformamide (DMF). The absolute configurations of four compounds were determined by X-ray single crystal diffraction. The fenchone-resorcinol analogs possessed high affinity and selectivity for the CB2 cannabinoid receptor. One of the analogues synthesized, 2-(2',6'-dimethoxy-4'-(2″-methyloctan-2″-yl)phenyl)-1,3,3-trimethylbicyclo[2.2.1]heptan-2-ol (1d), had a high affinity (K(i) = 3.51 nM) and selectivity for the human CB2 receptor (hCB2). In the [(35)S]GTP$\gamma$S binding assay, our lead compound was found to be a highly potent and efficacious hCB2 receptor agonist (EC(50) = 2.59 nM, E((max)) = 89.6%). Two of the fenchone derivatives were found to possess anti-inflammatory and analgesic properties. Molecular-modeling studies elucidated the binding interactions of 1d within the CB2 binding site.
Rachel Lasry, Maoz, Noam , Cheng, Albert W. , Tov, Nataly Yom , Kulenkampff, Elisabeth , Azagury, Meir , Yang, Hui , Ople, Cora , Markoulaki, Styliani , Faddah, Dina A. , Makedonski, Kirill , Sabbag, Ofra , Jaenisch, Rudolf , ו Buganim, Yosef . 2022.
“Fibroblasts-Derived From Pluripotent Cells Harboring A Single Allele Knockout In Two Pluripotency Genes Exhibit Dna Methylation Abnormalities And Pluripotency Induction Defects”. Biorxiv, Pp. 2022.05.18.492474.
תקציר A complete knockout (KO) of a single key pluripotency gene has been shown to drastically affect embryonic stem cell (ESC) function and epigenetic reprogramming. However, knockin (KI)/KO of a reporter gene only in one of two alleles in a single pluripotency gene is considered harmless and is largely used in the stem cell field. Here, we sought to understand the impact of simultaneous elimination of a single allele in two ESC key genes on pluripotency potential and acquisition. We established multiple pluripotency systems harboring KI/KO in a single allele of two different pluripotency genes (i.e. Nanog+/-; Sall4+/-, Nanog+/-; Utf1+/-, Nanog+/-; Esrrb+/- and Sox2+/-; Sall4+/-). Interestingly, although these double heterozygous mutant lines maintain their stemness and contribute to chimeras equally to their parental control cells, fibroblasts derived from these systems show a significant reduction in their capability to induce pluripotency either by Oct4, Sox2, Klf4 and Myc (OSKM) or by nuclear transfer (NT). Tracing the expression of Sall4 and Nanog, as representative key pluripotency targeted genes, at early phases of reprogramming could not explain the seen delay/blockage. Further exploration identifies abnormal methylation landscape around pluripotent and developmental genes in the double heterozygous mutant fibroblasts. Accordingly, treatment with 5-azacytidine two days prior to transgene induction rescues the reprogramming defects. This study emphasizes the importance of maintaining two intact alleles for pluripotency induction and suggests that insufficient levels of key pluripotency genes leads to DNA methylation abnormalities in the derived-somatic cells later on in development.Competing Interest StatementThe authors have declared no competing interest.
Odelia Tepper, Peled, Itamar , Fastman, Yair , Heinberg, Adina , Mitesser, Vera , Dzikowski, Ron , ו Yavin, Eylon . 2022.
“Fit-Pnas As Rna-Sensing Probes For Drug-Resistant Plasmodium Falciparum.”. Acs Sensors, 7, 1, Pp. 50–59. doi:10.1021/acssensors.1c01481.
תקציר Detecting RNA at single-nucleotide resolution is a formidable task. Plasmodium falciparum is the deadliest form of malaria in humans and has shown to gain resistance to essentially all antimalarial drugs including artemisinin and chloroquine. Some of these drug resistances are associated with single-nucleotide polymorphisms (SNPs). Forced-intercalation peptide nucleic acids (FIT-PNAs) are DNA mimics that are designed as RNA-sensing molecules that fluoresce upon hybridization to their complementary (RNA) targets. We have previously designed and synthesized FIT-PNAs that target the C580Y SNP in the K13 gene of P. falciparum. In addition, we have now prepared FIT-PNAs that target the K76T SNP in the CRT gene of P. falciparum. Both SNPs are common ones associated with artemisinin and chloroquine drug resistance, respectively. Our FIT-PNAs are conjugated to a simple cell-penetrating peptide (CPP) that consists of eight d-lysines (dK(8)), which renders these FIT-PNAs cell-permeable to infected red blood cells (iRBCs). Herein, we demonstrate that FIT-PNAs clearly discriminate between wild-type (WT) strains (NF54-WT: artemisinin-sensitive or chloroquine-sensitive) and mutant strains (NF54-C580Y: artemisinin-resistant or Dd2: chloroquine-resistant) of P. falciparum parasites. Simple incubation of FIT-PNAs with live blood-stage parasites results in a substantial difference in fluorescence as corroborated by FACS analysis and confocal microscopy. We foresee FIT-PNAs as molecular probes that will provide a fast, simple, and cheap means for the assessment of drug resistance in malaria─a tool that would be highly desirable for the optimal choice of antimalarial treatment in endemic countries.
J. Stokar, Gurt, I. , Cohen-Kfir, E. , Yakubovsky, O. , Hallak, N. , Benyamini, H. , Lishinsky, N. , Offir, N. , Tam, J. , ו Dresner-Pollak, R.. 2022.
“Hepatic Adropin Is Regulated By Estrogen And Contributes To Adverse Metabolic Phenotypes In Ovariectomized Mice”. Mol Metab, 60, Pp. 101482.
תקציר OBJECTIVE: Menopause is associated with visceral adiposity, hepatic steatosis and increased risk for cardiovascular disease. As estrogen replacement therapy is not suitable for all postmenopausal women, a need for alternative therapeutics and biomarkers has emerged. METHODS: 9-week-old C57BL/6 J female mice were subjected to ovariectomy (OVX) or SHAM surgery (n = 10 per group), fed a standard diet and sacrificed 6- & 12 weeks post-surgery. RESULTS: Increased weight gain, hepatic triglyceride content and changes in hepatic gene expression of Cyp17a1, Rgs16, Fitm1 as well as Il18, Rares2, Retn, Rbp4 in mesenteric visceral adipose tissue (VAT) were observed in OVX vs. SHAM. Liver RNA-sequencing 6-weeks post-surgery revealed changes in genes and microRNAs involved in fat metabolism in OVX vs. SHAM mice. Energy Homeostasis Associated gene (Enho) coding for the hepatokine adropin was significantly reduced in OVX mice livers and strongly inversely correlated with weight gain (r = -0.7 p < 0.001) and liver triglyceride content (r = -0.4, p = 0.04), with a similar trend for serum adropin. In vitro, Enho expression was tripled by 17β-estradiol in BNL 1 ME liver cells with increased adropin in supernatant. Analysis of open-access datasets revealed increased hepatic Enho expression in estrogen treated OVX mice and estrogen dependent ERα binding to Enho. Treatment of 5-month-old OVX mice with Adropin (i.p. 450 nmol/kg/twice daily, n = 4,5 per group) for 6-weeks reversed adverse adipokine gene expression signature in VAT, with a trended increase in lean body mass and decreased liver TG content with upregulation of Rgs16. CONCLUSIONS: OVX is sufficient to induce deranged metabolism in adult female mice. Hepatic adropin is regulated by estrogen, negatively correlated with adverse OVX-induced metabolic phenotypes, which were partially reversed with adropin treatment. Adropin should be further explored as a potential therapeutic target and biomarker for menopause-related metabolic derangement.
S. Kumar, Bar-Lev, L. , Sharife, H. , Grunewald, M. , Mogilevsky, M. , Licht, T. , Goveia, J. , Taverna, F. , Paldor, I. , Carmeliet, P. , ו Keshet, E.. 2022.
“Identification Of Vascular Cues Contributing To Cancer Cell Stemness And Function”. Angiogenesis, 25, Pp. 355-371.
תקציר Glioblastoma stem cells (GSCs) reside close to blood vessels (BVs) but vascular cues contributing to GSC stemness and the nature of GSC-BVs cross talk are not fully understood. Here, we dissected vascular cues influencing GSC gene expression and function to perfusion-based vascular cues, as well as to those requiring direct GSC-endothelial cell (EC) contacts. In light of our previous finding that perivascular tumor cells are metabolically different from tumor cells residing further downstream, cancer cells residing within a narrow, < 60 microm wide perivascular niche were isolated and confirmed to possess a superior tumor-initiation potential compared with those residing further downstream. To circumvent reliance on marker expression, perivascular GSCs were isolated from the respective locales based on their relative state of quiescence. Combined use of these procedures uncovered a large number of previously unrecognized differentially expressed GSC genes. We show that the unique metabolic milieu of the perivascular niche dominated by the highly restricted zone of mTOR activity is conducive for acquisition of GSC properties, primarily in the regulation of genes implicated in cell cycle control. A complementary role of vascular cues including those requiring direct glioma/EC contacts was revealed using glioma/EC co-cultures. Outstanding in the group of glioma cells impacted by nearby ECs were multiple genes responsible for maintaining GSCs in an undifferentiated state, a large fraction of which also relied on Notch-mediated signaling. Glioma-EC communication was found to be bidirectional, evidenced by extensive Notch-mediated EC reprogramming by contacting tumor cells, primarily metabolic EC reprogramming.
INTRODUCTION: As in all vertebrates, reproduction in fish is regulated by GnRH control on gonadotrophic hormones (GtH) activity. However, the neuroendocrine factors that promote GnRH and GtH activity are unknown. In Nile tilapia (Oreochromis niloticus), sexual activity and reproduction ability depend on social rank; only dominant males and females reproduce. Here, this characteristic of dominant fish allows us to compare brain and pituitary gene expression in animals that do and do not reproduce, aiming to reveal mechanisms that regulate reproduction. METHODS: an extensive transcriptome analysis was performed, combining two sets of transcriptomes: a novel whole-brain and pituitary transcriptome of established dominant and subordinate males, together with a cell-specific transcriptome of LH and FSH cells. Pituitary incubation assay validated the direct effect of steroid application on chosen genes and GtH secretion. RESULTS: in most dominant fish, as determined behaviorally, the gonadosomatic index was higher than in subordinate fish, and the leading upregulated pituitary genes were those coding for GtHs. In the brain, various neuropeptide genes, including isotocin, cholecystokinin, and MCH, were upregulated; these may be related to reproductive status through effects on behavior and feeding. In a STRING network analysis combining the two transcriptome sets, brain aromatase, highly expressed in LH cells, is the most central gene with the highest number of connections. In the pituitary incubation assay, testosterone and estradiol increased the secretion of LH and specific gene transcription. CONCLUSIONS: the close correlation between behavioral dominance and reproductive capacity in tilapia allows unraveling novel genes that may regulate the HPG axis, highlighting aromatase as the main factor affecting the brain and pituitary in maintaining a sexually active organism.
Yonit Yitzhak, Gaikwad, Hanmant , Weiss-Sadan, Tommy , Merquiol, Emmanuelle , Turk, Boris , ו Blum, Galia . 2022.
“Improved Cathepsin Probes For Sensitive Molecular Imaging.”. Molecules (Basel, Switzerland), 27, 3. doi:10.3390/molecules27030842.
תקציר Cysteine cathepsin proteases are found under normal conditions in the lysosomal compartments of cells, where they play pivotal roles in a variety of cellular processes such as protein and lipid metabolism, autophagy, antigen presentation, and cell growth and proliferation. As a consequence, aberrant localization and activity contribute to several pathologic conditions such as a variety of malignancies, cardiovascular diseases, osteoporosis, and other diseases. Hence, there is a resurgence of interest to expand the toolkit to monitor intracellular cathepsin activity and better ascertain their functions under these circumstances. Previous fluorescent activity-based probes (ABPs) that target cathepsins B, L, and S enabled detection of their activity in intact cells as well as non-invasive detection in animal disease models. However, their binding potency is suboptimal compared to the cathepsin inhibitor on which they were based, as the P1 positive charge was capped by a reporter tag. Here, we show the development of an improved cathepsin ABP that has a P1 positive charge by linking the tag on an additional amino acid at the end of the probe. While enhancing potency towards recombinant cathepsins, the new probe had reduced cell permeability due to additional peptide bonds. At a second phase, the probe was trimmed; the fluorophore was linked to an extended carbobenzoxy moiety, leading to enhanced cell permeability and superb detection of cathepsin activity in intact cells. In conclusion, this work introduces a prototype design for the next generation of highly sensitive ABPs that have excellent detection of cellular cathepsin activity.
