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186


Aldose reductase driven changes in genes linked to fatty acid metabolism and cellular senescence in high fat diet fed mice [Meeting Abstract]

Sekaran, K.; Thiagarajan, D.; Ramasamy, R.
ISI:000430468400871
ISSN: 0002-8614
CID: 3084842

Small molecule antagonists of RAGE-DIAPH1: Novel therapeutic opportunities in metabolic and chronic disease [Meeting Abstract]

Manigrasso, M B; Quadri, N; Li, Q; DeVita, R J; Ramasamy, R; Shekhtman, A; Schmidt, A M
Our previous work has shown that the cytoplasmic tail (ct) of RAGE is essential for RAGE ligand-mediated signal transduction and consequent modulation of gene expression and cellular properties. RAGE signaling requires interaction of ctRAGE with the intracellular effector, mammalian diaphanous 1, or DIAPH1. Given the complex, multi-ligand nature of ligands binding to the extracellular domains of RAGE, we sought to discover small molecule inhibitors of the interaction of ctRAGE with DIAPH1. Prompted by our identification of 13 small molecules that block the interaction of ctRAGE-DIAPH1, we pursued structure-activity relationship experiments to identify analogues potentially able to delay or prevent the progression of RAGE-related chronic diseases, such as diabetes. In vitro binding studies Native tryptophan fluorescence experiments were conducted using 1mM of compound dissolved in phosphate buffer and DMSO. 10 nM ctRAGE solution was titrated from 0.1 nM-100 muM and the dissociation constants, Kd, were estimated from the changes in peak fluorescence intensities as a function of the free compound concentration. NMR experiments were performed operating at 1H frequencies of 500 MHz and 700 MHz. NMR samples contained 50 muM of [U-15N] ctRAGE and 10 muM of the compound. All spectra were collected at 298K, which yielded high quality NMR spectra of [U-15N] RAGE tail. Compound binding to ctRAGE was identified as at least a 0.01 ppm change in the ctRAGE chemical shift. Small molecule leads were identified and referred to as NYU 1-5 (Table 1). Ex vivo biological activity assays Inhibition of smooth muscle cell (SMC) migration induced by RAGE ligands after incubation with indicated NYU compounds. SMCs were grown to confluence and starved overnight. The next morning, the medium was removed, compounds were added and the monolayer was wounded using a p200 pipette tip and allowed to incubate for 1.5h. Following incubation, compounds were removed and fresh medium containing the RAGE ligand, CML-AGE (10 mug/ml) was added for 4h. Images were taken, measured and an area ingrowth of effective migrating cells was calculated (Table 1). In vivo studies (A) Delayed type hypersensitivity. Female CF-1 mice were sensitized over the left inguinal lymph node with a methylated bovine serum albumin emulsion. On day 19 and 20 after sensitization, mice received, by oral gavage, the test compounds (5 mg/kg/bw) or vehicle twice daily. Post-final compound injection, mBSA was injected into the left hind paw. Inflammation was assessed using a semiquantitative scoring system (Figure 1). (B) Myocardial infarction in diabetic mice. Male C57BL/6 mice were rendered diabetic with STZ and were diabetic for 2 months. Mice were subjected to left anterior descending coronary artery occlusion followed by reperfusion (LAD/reperfusion). After 48h, the hearts were excised. TTC and Evan's blue staining was used to measure infarct area. Mice received a total of 7 doses of either VEHICLE or an NYU compound (Figure 2). In summary, refined compounds that inhibit the interaction of ctRAGE with DIAPH1, which exhibit in vitro and in vivo inhibition of RAGE-dependent molecular processes, present attractive scaffolds for the development of therapeutics against RAGE-mediated diseases, such as those linked to diabetic complications and chronic inflammation. We conclude that these identified compounds hold significant potential as druggable scaffolds for further development and testing for the treatment of RAGE-related disorders
EMBASE:622545638
ISSN: 1530-6860
CID: 3160432

The UAE healthy future study: a pilot for a prospective cohort study of 20,000 United Arab Emirates nationals

Abdulle, Abdishakur; Alnaeemi, Abdullah; Aljunaibi, Abdullah; Al Ali, Abdulrahman; Al Saedi, Khaled; Al Zaabi, Eiman; Oumeziane, Naima; Al Bastaki, Marina; Al-Houqani, Mohammed; Al Maskari, Fatma; Al Dhaheri, Ayesha; Shah, Syed M; Loney, Tom; El-Sadig, Mohamed; Oulhaj, Abderrahim; Wareth, Leila Abdel; Al Mahmeed, Wael; Alsafar, Habiba; Hirsch, Benjamin; Al Anouti, Fatme; Yaaqoub, Jamila; Inman, Claire K; Al Hamiz, Aisha; Al Hosani, Ayesha; Haji, Muna; Alsharid, Teeb; Al Zaabi, Thekra; Al Maisary, Fatima; Galani, Divya; Sprosen, Tim; El Shahawy, Omar; Ahn, Jiyoung; Kirchhoff, Tomas; Ramasamy, Ravichandran; Schmidt, Ann Marie; Hayes, Richard; Sherman, Scott; Ali, Raghib
BACKGROUND:The United Arab Emirates (UAE) is faced with a rapidly increasing burden of non-communicable diseases including obesity, diabetes, and cardiovascular disease. The UAE Healthy Future study is a prospective cohort designed to identify associations between risk factors and these diseases amongst Emiratis. The study will enroll 20,000 UAE nationals aged ≥18 years. Environmental and genetic risk factors will be characterized and participants will be followed for future disease events. As this was the first time a prospective cohort study was being planned in the UAE, a pilot study was conducted in 2015 with the primary aim of establishing the feasibility of conducting the study. Other objectives were to evaluate the implementation of the main study protocols, and to build adequate capacity to conduct advanced clinical laboratory analyses. METHODS:Seven hundred sixty nine UAE nationals aged ≥18 years were invited to participate voluntarily in the pilot study. Participants signed an informed consent, completed a detailed questionnaire, provided random blood, urine, and mouthwash samples and were assessed for a series of clinical measures. All specimens were transported to the New York University Abu Dhabi laboratories where samples were processed and analyzed for routine chemistry and hematology. Plasma, serum, and a small whole blood sample for DNA extraction were aliquoted and stored at -80 °C for future analyses. RESULTS:Overall, 517 Emirati men and women agreed to participate (68% response rate). Of the total participants, 495 (95.0%), 430 (82.2%), and 492 (94.4%), completed the questionnaire, physical measurements, and provided biological samples, respectively. CONCLUSIONS:The pilot study demonstrated the feasibility of recruitment and completion of the study protocols for the first large-scale cohort study designed to identify emerging risk factors for the major non-communicable diseases in the region.
PMCID:5755402
PMID: 29304844
ISSN: 1471-2458
CID: 2899502

Patterns of tobacco use in the United Arab Emirates Healthy Future (UAEHFS) pilot study

Al-Houqani, Mohammed; Leinberger-Jabari, Andrea; Al Naeemi, Abdullah; Al Junaibi, Abdullah; Al Zaabi, Eiman; Oumeziane, Naima; Kazim, Marina; Al Maskari, Fatima; Al Dhaheri, Ayesha; Abdel Wareth, Leila; Al Mahmeed, Wael; Alsafar, Habiba; Al Anouti, Fatme; Abdulle, Abdishakur; Inman, Claire K; Al Hamiz, Aisha; Haji, Muna; Ahn, Jiyoung; Kirchhoff, Tomas; Hayes, Richard B; Ramasamy, Ravichandran; Schmidt, Ann Marie; El Shahawy, Omar; Weitzman, Michael; Ali, Raghib; Sherman, Scott
INTRODUCTION/BACKGROUND:Self-reported tobacco use in the United Arab Emirates is among the highest in the region. Use of tobacco products other than cigarettes is widespread, but little is known about specific behavior use patterns. There have been no studies that have biochemically verified smoking status. METHODS:The UAE Healthy Future Study (UAEHFS) seeks to understand the causes of non-communicable diseases through a 20,000-person cohort study. During the study pilot, 517 Emirati nationals were recruited to complete a questionnaire, provide clinical measurements and biological samples. Complete smoking data were available for 428 participants. Validation of smoking status via cotinine testing was conducted based on complete questionnaire data and matching urine samples for 399 participants, using a cut-off of 200ng/ml to indicate active smoking status. RESULTS:Self-reported tobacco use was 36% among men and 3% among women in the sample. However, biochemical verification of smoking status revealed that 42% men and 9% of women were positive for cotinine indicating possible recent tobacco use. Dual and poly-use of tobacco products was fairly common with 32% and 6% of the sample reporting respectively. CONCLUSIONS:This is the first study in the region to biochemically verify tobacco use self-report data. Tobacco use in this study population was found to be higher than previously thought, especially among women. Misclassification of smoking status was more common than expected. Poly-tobacco use was also very common. Additional studies are needed to understand tobacco use behaviors and the extent to which people may be exposed to passive tobacco smoke. IMPLICATIONS/CONCLUSIONS:This study is the first in the region to biochemically verify self-reported smoking status.
PMCID:5976156
PMID: 29847569
ISSN: 1932-6203
CID: 3136292

Training scientists as future industry leaders: teaching translational science from an industry executive's perspective

Lee, Gloria; Kranzler, Jay D; Ramasamy, Ravichandran; Gold-von Simson, Gabrielle
PhDs and post-doctoral biomedical graduates, in greater numbers, are choosing industry based careers. However, most scientists do not have formal training in business strategies and venture creation and may find senior management positions untenable. To fill this training gap, "Biotechnology Industry: Structure and Strategy" was offered at New York University School of Medicine (NYUSOM). The course focuses on the business aspects of translational medicine and research translation and incorporates the practice of business case discussions, mock negotiation, and direct interactions into the didactic. The goal is to teach scientists at an early career stage how to create solutions, whether at the molecular level or via the creation of devices or software, to benefit those with disease. In doing so, young, talented scientists can develop a congruent mindset with biotechnology/industry executives. Our data demonstrates that the course enhances students' knowledge of the biotechnology industry. In turn, these learned skills may further encourage scientists to seek leadership positions in the field. Implementation of similar courses and educational programs will enhance scientists' training and inspire them to become innovative leaders in the discovery and development of therapeutics.
PMCID:5898379
PMID: 29657853
ISSN: 2059-268x
CID: 3042632

Targeted drug discovery and development, from molecular signaling to the global market: an educational program at New York University, 5-year metrics

Lee, Gloria; Plaksin, Joseph; Ramasamy, Ravichandran; Gold-von Simson, Gabrielle
Drug discovery and development (DDD) is a collaborative, dynamic process of great interest to researchers, but an area where there is a lack of formal training. The Drug Development Educational Program (DDEP) at New York University was created in 2012 to stimulate an improved, multidisciplinary DDD workforce by educating early stage scientists as well as a variety of other like-minded students. The first course of the program emphasizes post-compounding aspects of DDD; the second course focuses on molecular signaling pathways. In five years, 196 students (candidates for PhD, MD, Master's degree, and post-doctoral MD/PhD) from different schools (Medicine, Biomedical Sciences, Dentistry, Engineering, Business, and Education) completed the course(s). Pre/post surveys demonstrate knowledge gain across all course topics. 26 students were granted career development awards (73% women, 23% underrepresented minorities). Some graduates of their respective degree-granting/post-doctoral programs embarked on DDD related careers. This program serves as a framework for other academic institutions to develop compatible programs designed to train a more informed DDD workforce.
PMCID:5898375
PMID: 29657854
ISSN: 2059-268x
CID: 3042642

The Formin, DIAPH1, is a Key Modulator of Myocardial Ischemia/Reperfusion Injury

O'Shea, Karen M; Ananthakrishnan, Radha; Li, Qing; Quadri, Nosirudeen; Thiagarajan, Devi; Sreejit, Gopalkrishna; Wang, Lingjie; Zirpoli, Hylde; Aranda, Juan Francisco; Alberts, Arthur S; Schmidt, Ann Marie; Ramasamy, Ravichandran
The biochemical, ionic, and signaling changes that occur within cardiomyocytes subjected to ischemia are exacerbated by reperfusion; however, the precise mechanisms mediating myocardial ischemia/reperfusion (I/R) injury have not been fully elucidated. The receptor for advanced glycation end-products (RAGE) regulates the cellular response to cardiac tissue damage in I/R, an effect potentially mediated by the binding of the RAGE cytoplasmic domain to the diaphanous-related formin, DIAPH1. The aim of this study was to investigate the role of DIAPH1 in the physiological response to experimental myocardial I/R in mice. After subjecting wild-type mice to experimental I/R, myocardial DIAPH1 expression was increased, an effect that was echoed following hypoxia/reoxygenation (H/R) in H9C2 and AC16 cells. Further, compared to wild-type mice, genetic deletion of Diaph1 reduced infarct size and improved contractile function after I/R. Silencing Diaph1 in H9C2 cells subjected to H/R downregulated actin polymerization and serum response factor-regulated gene expression. Importantly, these changes led to increased expression of sarcoplasmic reticulum Ca2+ ATPase and reduced expression of the sodium calcium exchanger. This work demonstrates that DIAPH1 is required for the myocardial response to I/R, and that targeting DIAPH1 may represent an adjunctive approach for myocardial salvage after acute infarction.
PMCID:5832565
PMID: 29239839
ISSN: 2352-3964
CID: 2844032

The AGE-RAGE axis in an Arab population: The United Arab Emirates Healthy Futures (UAEHFS) pilot study

Inman, Claire K; Aljunaibi, Abdullah; Koh, Hyunwook; Abdulle, Abdishakur; Ali, Raghib; Alnaeemi, Abdullah; Al Zaabi, Eiman; Oumeziane, Naima; Al Bastaki, Marina; Al-Houqani, Mohammed; Al-Maskari, Fatma; Al Dhaheri, Ayesha; Shah, Syed M; Abdel Wareth, Laila; Al Mahmeed, Wael; Alsafar, Habiba; Al Anouti, Fatme; Al Hosani, Ayesha; Haji, Muna; Galani, Divya; O'Connor, Matthew J; Ahn, Jiyoung; Kirchhoff, Tomas; Sherman, Scott; Hayes, Richard B; Li, Huilin; Ramasamy, Ravichandran; Schmidt, Ann Marie
Aims/UNASSIGNED:The transformation of the United Arab Emirates (UAE) from a semi-nomadic to a high income society has been accompanied by increasing rates of obesity and Type 2 diabetes mellitus. We examined if the AGE-RAGE (receptor for advanced glycation endproducts) axis is associated with obesity and diabetes mellitus in the pilot phase of the UAE Healthy Futures Study (UAEHFS). Methods/UNASSIGNED:517 Emirati subjects were enrolled and plasma/serum levels of AGE, carboxy methyl lysine (CML)-AGE, soluble (s)RAGE and endogenous secretory (es)RAGE were measured along with weight, height, waist and hip circumference (WC/HC), blood pressure, HbA1c, Vitamin D levels and routine chemistries. The relationship between the AGE-RAGE axis and obesity and diabetes mellitus was tested using proportional odds models and linear regression. Results/UNASSIGNED:After covariate adjustment, AGE levels were significantly associated with diabetes status. Levels of sRAGE and esRAGE were associated with BMI and levels of sRAGE were associated with WC/HC. Conclusions/UNASSIGNED:The AGE-RAGE axis is associated with diabetes status and obesity in this Arab population. Prospective serial analysis of this axis may identify predictive biomarkers of obesity and cardiometabolic dysfunction in the UAEHFS.
PMCID:5691216
PMID: 29204365
ISSN: 2214-6237
CID: 2892882

Levels of soluble rage but not endogenous secretory (ES) rage differ between type 2 diabetic versus control subjects in the United Arab Emirates [Meeting Abstract]

Abdulle, A; Inman, C K; Saleh, A; Noshi, M; Galani, D; Abdelwareth, L; Alsafar, H; Elfatih, A; Al, shamsi H; Ali, R; Li, H; Ramasamy, R; Marie, Schmidt A; Benbarka, M M; Hassan, M H
Background: The United Arab Emirates (UAE) is experiencing increasing rates of obesity, type 2 diabetes (T2D) and its complications. We tested if soluble levels of cell surface-cleaved RAGE (sRAGE) or endogenous secretory RAGE (esRAGE), the product of alternative mRNA splicing of AGER, are associated with T2D and obesity in the UAE.
Method(s): A case-control study was performed in the Diabetes, Endocrinology and General Medical Clinics of the Sheikh Khalifa Medical City in Abu Dhabi. 216 T2D subjects and 215 controls (mean age 57.4+/-12.1 vs. 50.7+/-15.4 years, respectively) were enrolled. Plasma sRAGE and esRAGE levels, anthropomorphic characteristics and routine chemistries were measured. The relationship between sRAGE and esRAGE with obesity and T2D status was tested using a linear regression model.
Result(s): Univariate analyses comparing T2D case and control subjects revealed differences in sRAGE (1,033+/-545.3 vs. 1,169+/-664.1 pg/ml, respectively; p=0.02) but not esRAGE. Covariate adjustment revealed that differences in sRAGE were significant after correction for age and sex and additionally for waist-hip ratio (WHR); total cholesterol (TC), HDL; hsCRP; Vit D; or triglyceride (TG) levels separately. In cases or controls, we tested associations of body mass index (BMI) or WHR with sRAGE and esRAGE. In controls but not T2D cases, sRAGE and esRAGE were significantly associated with BMI, after correction for age and sex and additionally for eGFR; blood pressure; TC, HDL; hsCRP; Vit D; creatinine; TG and HbA1c in a combined model. In the case of WHR, in controls and T2D cases, there were no associations with sRAGE, but only in T2D cases, WHR was associated with esRAGE after correction for age and sex and blood pressure; TC, HDL; hsCRP, HbA1c, creatinine; TG, eGFR, Vit D and TG in a combined model.
Conclusion(s): Levels of sRAGE but not esRAGE distinguish T2D case vs. controls in the UAE population. Genetic and unique obesity-dependent factors may underlie lack of association between esRAGE in cases vs. controls, which may affect vulnerability to T2D and its complications in the UAE
EMBASE:633701273
ISSN: 1533-3450
CID: 4750412

PROFILING SRF and MODULATION OF SRF TARGET GENES IN A MOUSE MODEL OF CARDIAC AGING [Meeting Abstract]

Gupta, S; Gopalkrishna, S; Schmidt, A; Ramasamy, R
ISI:000402876300668
ISSN: 1532-5415
CID: 2611242