Pharmacology, Toxicology and Environmental Health Commons^™

Impaired Β-Cell Neogenesis In A Mouse Model Of Metabolic Syndrome, Modhi Abdullah Alshammari

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Pancreatic islet β-cell plays an essential role in insulin release and hence glucose homeostasis. The maintenance of glucose homeostasis depends on β-cell ability to cope with enough insulin to fulfill metabolic and physiological demands. Adequate insulin release is the result of highly complex and dynamic interplays between acute changes in β- cell electrical activity, exocytosis and chronic adaptations in cellular function, volume, mass and proliferation. All of this appears modulated, to some extent, by the functional presence of Slc12a2 symporters, also known as Na+K+2Cl– cotransporter-1 (Nkcc1), which accumulates intracellular Cl– above its electrochemical equilibrium. Recent studies from our laboratory showed …

Heightened Levels Of Microvesicle Particles Resulting From Combination Of Ethanol And Thermal Burn Injury, Chad Alan Brewer

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Ethanol (EtOH), in combination with thermal burn injury, is a clinically significant problem resulting in an increase in morbidity and mortality due to acute multi-organ toxicity from excess systemic cytokine release. This intoxicated thermal burn affects close to 50% of the total numbers of hospital-admitted burn patients and currently has no standard treatment. However, using in vitro cellular and in vivo murine models, our group has provided data implicating the augmented production of the lipid mediator Platelet-activating factor (PAF) in keratinocytes in response to intoxicated thermal burn injury in the subsequent pathology. Of importance, our group has demonstrated that activation …

Ahr-Mediated Transcriptional Regulation Of The Human Immunoglobulin Hs1.2 Enhancer, Sydney White

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The 3'IGHRR is thought to be responsible for the transcription of the immunoglobulin heavy chain (IGH) gene locus, which is essential for the production of antibodies. The human 3’IGHRR, which is duplicated in humans, contains the hs3, hs4, and hs1.2 enhancers. Additionally, the hs1.2 enhancer is polymorphic in humans and consists of a 53 bp invariant sequence that can be repeated one to four times. Previous experiments in a mouse and human B-cell line model have shown that the high affinity AhR ligand and environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can induce hs1.2 enhancer activity in an AhR-dependent manner. The AhR is …

Impact Of Theory-Based Interventions On Meaningfulness Of Undergraduate Nursing Pharmacology Student Learning, Betsy L. Mauldin

Nursing Theses and Dissertations

Objective: Nursing pharmacology is a complex and content-dense course, often cited as difficult for nurse educators and students and a reason for not progressing in nursing curricula. Even nurses who experience high academic performance report feeling ill-prepared to adequately perform medication management for nursing practice in the current fast-paced environment. The objective of this five-chapter portfolio is to explain the development and implementation of a two-pronged intervention to facilitate meaningful learning of pharmacology principles within nursing students. Chapter 1 describes an overview of the approach to the intervention.

Methods: Chapter 2 describes one prong of the study intervention, the Pharmacology …

The Protective Effects Of Mir-210 Modified Endothelial Progenitor Cells Released Exosomes In Hypoxia/Reoxygenation Injured Neurons, Sri Meghana Yerrapragada

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Endothelial progenitor cells (EPCs) have been shown to provide beneficial effects on oxidative stress. Exosomes (EXs) released from these stem cells could be one of the major contributors, as they are known to convey the benefit of one cell to another cell via microRNAs (miRNA). At first, we determined that EPCs release more EXs when they are serum-starved for 48 hours., and by determining the microRNA-210 (miR-210) levels in the EXs, we found that miRNA is being transferred from cells to EXs. Meanwhile, miR-210 is gaining popularity in reducing elevated oxidative stress levels. In this study, we investigated the role …

The Effect Of Circadian Clock Modulation On Cisplatin Cytotoxicity, Nadeen Nibal Ahmad Anabtawi

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Cisplatin is a DNA damage-based chemotherapeutic drug widely used to treat various types of cancers; however, the treatment's toxicity restricts its efficiency. Studies have shown that the circadian rhythm controls the DNA damage response and affects the repair pathways of cisplatin-induced DNA damage. Circadian clock modulation, therefore, has been proposed to be a potential mechanism for enhancing cisplatin tolerability. Here we used clock-enhancing molecules to evaluate the effect of pharmacological clock modulation on cisplatin cytotoxicity. Using cultured human cell lines, cisplatin cytotoxicity was found to be attenuated following treatment with circadian-enhancing molecules KS15 and SR8278. Moreover, the protein and mRNA …

Functions Of Atr Kinase In Terminally Differentiated Human Epidermal Keratinocyles And In Human Ex-Vivo Skin After Exposure To Ultraviolet B Radiation, Vivek Shashank Nag Gogusetti

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The functions of Ataxia telangiectasia and Rad-3 related protein (ATR) is very much important in a cell, as it is a DNA damage response protein, which plays an important role in cell division, DNA repair and apoptosis. This protein helps in proliferation in the actively DNA dividing normal cells and in cancer cells. The functions of ATR in a proliferating cell are well studied and known to involve regulation of replication fork and cell cycle progression after DNA damage. Whereas, in a non-replicating cell, the functions of ATR are not so well known. In the human body, most of the …

Xeroderma Pigmentosum A Deficiency Results In Increased Generation Of Microvesicle Particles In Response To Ultraviolet B Radiation, Christian Lea Rajeshkumar

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Xeroderma Pigmentosum is a genetic disorder in which ability to repair DNA damage such as from UV radiation is decreased. Nucleotide excision repair is known for repairing DNA damage caused by UV radiation and XPA plays a major role in recognizing and eliminating abnormal section of DNA. Therefore, XPA deficiency decreases repair efficiency of DNA. Of note, XPA deficiency is linked with photosensitivity. Microvesicle particles are membrane-bound particles which are released into the extracellular environment in response to multiple stimuli including the lipid Platelet activating factor (PAF). Previous studies have shown that XPA deficiency can induce increase production of reactive …

Stress-Induced Senescence In Human Dermal Fibroblasts : Effects Of Creatine And Nicotinamide Post Stress Treatment, Venkata Sravya Arikatla

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In skin connective tissue, dermal fibroblasts appear to be the most prevalent cell type. They are in charge of making the extracellular matrix that makes up the skin's connective tissue, and also involved in wound healing. Moreover, they produce Insulin-like growth factor-1 (IGF-1) which helps in activation of Insulin growth factor-1 receptor (IGF-1R). This receptor helps to control cell proliferation and responses to DNA-damaging substances such as UVB radiation, reactive oxygen species (ROS), and therapeutic drugs. According to our findings, lack of IGF-1 expression in the dermis of elderly patients due to fibroblast senescence (senescence is characterized by which cells …

David S. Miller: Scientist, Mentor, Friend--A Tribute And Thank You, Björn Bauer, J. Larry Renfro, Karl J. Karnaky, Rosalinde Masereeuw, Gert Fricker, Ron E. Cannon, Anika M. S. Hartz

Pharmaceutical Sciences Faculty Publications

David S. Miller was Acting Scientific Director of the Division of Intramural Research at the National Institute of Environmental Health Sciences, National Institutes of Health, and Head of the Intracellular Regulation Group in the Laboratory of Toxicology and Pharmacology before he retired in 2016. David received his Ph.D. in biochemistry from the University of Maine in 1973. David was a Group Leader at the Michigan Cancer Foundation before joining the NIEHS in 1985. His research covered a wide range from renal excretory transport mechanisms to regulation of transporters at the blood-CSF and blood-brain barriers, from fish, amphibians and birds to …

The Feeding Pattern Of C57bl/6j Mice, Yakshkumar Dilipbhai Rathod

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The feeding pattern and control of energy intake in social mice are poorly understood. Here, we determined and quantify the normal nocturnal feeding pattern of group-housed male and female mice of the C57BL/6J genetic background fed a chow diet. Mice at 10 and 20weeks of age showed the expected age-dependent increase in lean and fat mass being them more pronounced in males. Under ad libitum conditions, male and female mice ate comparable amounts of food per unit of body weight irrespective of gender. The analysis of the feeding microstructure revealed that energy intake in females is the result of significantly …

Insulin-Like Growth Factor-1 (Igf-1) Impacts P53-Regulated Gene Products In Uvb-Irradiated Human Keratinocytes And Skin Epidermis, Abdulrhaman Mohammed Mohammed Alkawwar

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Skin cancer is the most prevalent human malignancy and is primarily caused by ultraviolet (UV) wavelengths of sunlight. However, the fact that most skin cancers occur in people over the age of 60 indicates that advantaged age is a second skin cancer risk factor. Why geriatric skin is prone to developing skin cancers is not clear, but several studies have shown that dermal fibroblasts in geriatric skin express lower levels of the hormone insulin-like growth factor-1 (IGF-1) than young adult skin and that deficient IGF-1 signaling negatively impacts how epidermal keratinocytes respond to UVB radiation. A major regulator of the …

Measuring Functional Brain Recovery In Regenerating Planarians By Assessing The Behavioral Response To The Cholinergic Compound Cytisine, Oné R. Pagán, Debra L. Baker, Sean Deats, Mary O'Brien, Rochelle Dymond, Gabriella Demichele

Biology Faculty Publications

Planarians are traditional model invertebrates in regeneration and developmental biology research that also display a variety of quantifiable behaviors useful to screen for pharmacologically active compounds. One such behavior is the expression of seizure-like movements (pSLMs) induced by a variety of substances. Previous work from our laboratory showed that cocaine, but not nicotine, induced pSLMs in intact but not decapitated planarians. Interestingly, as decapitated planarians regenerated their heads, they gradually recovered their sensitivity to cocaine. These results suggested a method to assess planarian brain regeneration and a possible way of identifying compounds that could enhance or hold back brain regeneration. …

Topical Photodynamic Therapy Generates Microvesicle Particles, Oladayo Ayobami Oyebanji

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Photodynamic therapy (PDT) involves the use of light at an appropriate wavelength acting on a photosensitizing chemical to cause cell death via generation of reactive oxygen species. PDT has been useful in the management of skin conditions (like acne, psoriasis) and cancers like superficial skin, esophageal and non-small cell lung cancers. In addition to these therapeutic effects, previous murine studies from our group have demonstrated that topical PDT induces immunosuppression in vivo. Thus, topical PDT of skin can generate systemic effects through unknown mechanisms. Our group showed that PDT induces an immunosuppressive effect which occurs partly via Platelet-Activating Factor Receptor …

Multiple Genotoxic Agents Activate Atr Kinase Signaling In Quiescent Human Cells, Mariyyah Ahmed O. Madkhali

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The ATR protein kinase is activated in response to DNA damage and other forms of genotoxic stress caused by both environmental carcinogens and anti-cancer drugs. However, much of our understanding of ATR kinase function is limited to proliferating cells in which DNA replication stress is the primary signal for ATR activation and where the major regulatory targets of ATR signaling are proteins involved in DNA synthesis and cell cycle progression. Here we have used HaCaT keratinocytes maintained in a non-replicating, quiescent state in vitro to examine how cell killing by different genotoxic agents is impacted by cell growth status and …

Role Of Exercise In Macrophage Polarization Of Perivascular Adipose Tissue And Adipose Tissue Inflammation In Hypertensive Mice Model, Venkata Sai Usha Sri Polaki

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Hypertension, also known as high blood pressure, is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. It can lead to severe health complications and increase the risk of heart disease, stroke, and sometimes death. Perivascular adipose tissue (PVAT) is known as the adipose tissue (AT) surrounding all the blood vessels and plays a critical role in the pathogenesis of the vascular disease. In vascular pathologies, PVAT increases in volume and becomes dysfunctional, with altered cellular composition and molecular characteristics. Macrophages have been found to accumulate in PVAT during hypertension, which might be involved …

Identification Of New Metabolic Mutations In The Fission Yeast Schizosaccharomyces Pombe That Sensitize The Cell To Hydroxyurea, Alaa Mahdi

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Cancer is a life-threatening illness and innovative research is therefore required to fuel the development of new anti-cancer therapies. As an anti-proliferative drug, hydroxyurea (HU) has been used in the treatment of various neoplastic and non-neoplastic diseases such as sickle cell anemia, psoriasis, and viral infections. HU is a well-known inhibitor of ribonucleotide reductase (RNR), an enzyme that generates dNTPs for DNA replication and repair. In our genetic screen in fission yeast looking for mutants with defects in checkpoint response, we also found a set of mutants that are highly sensitive to HU but with a functional checkpoint response. It …

Effects Of Creatine And Nicotinamide On Experimentally Induced Senescence In Dermal Fibroblasts, Avinash Satyanarayan Mahajan

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Dermal fibroblasts provide structural support by producing collagen and other structural/support proteins beneath the epidermis. Fibroblasts also produce Insulin-like growth factor-1 (IGF-1), which binds to the IGF-1 receptors (IGF-1Rs) on keratinocytes to activate signaling pathways that regulate cell proliferation and cellular responses to genotoxic stressors like ultraviolet B radiation found in sunlight. Our group has determined that the lack of IGF-1 expression due to fibroblast senescence in the dermis of geriatric individuals is correlated with an increased incidence of skin cancer in geriatric patients. The present studies were designed to test the hypothesis that pro-energetics like creatine monohydrate and nicotinamide …

Characterization Of Proteins Found In Serum And Sputum Samples From Ventilator Associated Pneumonia Patients, Hima Priya Yenuga

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Ventilator associated pneumonia (VAP) is the most common nosocomial infection leading to increased mortality in ICU patients. The main goal of this project was to evaluate and analyze a number of different biomarkers of disease that may be involved in the transition to pneumonia in patients on ventilators. Patients in this study were in the ICU, required greater than or equal to 48 hours of mechanical ventilation, and had a Clinical Pulmonary Infection Score greater than or equal to 6. For this study we recruited 16 subjects who were on ventilator for more than 48 hours, obtained serum and sputum …

Implication Of Mirna-149 In Platelet-Activating-Factor-Receptor-Mediated Effects On Lung Cancer Growth And Treatment Efficacy, Shreepa J. Chauhan

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Lung cancer remains the leading cause of cancer-related deaths, with low response rates to the current treatment options, indicating the need to explore potential factors, involved in lung cancer growth or impeding the efficacy of therapeutic agents. Studies, including ours, have shown the critical roles of a G-protein coupled, platelet-activating factor-receptor (PAF-R) in augmenting tumor growth or limiting therapy effectiveness in various experimental cancer models via mechanisms involving the secretion of microvesicle particles (MVPs). However, the effects of PAF-R pathway with microRNAs (miRs) have not been studied. In particular, while miR-149 has been shown to play oncogenic roles in other …

Investigation Of Riluzole’S Synaptic Protection Mechanism Through Hsf1-Bdnf Axis, Yi Zhang

Theses and Dissertations (ETD)

The FDA-approved amyotrophic lateral sclerosis (ALS) drug Riluzole has great potential in treating Alzheimer’s disease (AD) based on promising animal data as well as its known action on modulating synaptic transmission. However, its detailed mechanism of action is not fully understood. Here, we proposed work aiming to address this aspect via focus- ing on the Heat Shock Factor 1 (HSF1)-dependent mechanisms. We found that Riluzole could increase HSF1 and BDNF (Brain-Derived Neurotrophic Factor) expression both at transcriptional and translational levels. CA1 (Cornu Ammonia, the first region in the hip- pocampal circuit), is its main target. We also demonstrated a protective …

Reversal Of P-Glycoprotein And Breast Cancer Resistance Protein Mediated Multidrug Resistance In Vitro Using In Silico Identified Novel Compounds, Amila Nanayakkara

Biological Sciences Theses and Dissertations

Multidrug resistance (MDR) is a major cause of chemotherapy failure. Overexpression of ATP-binding cassette (ABC) transporters, P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) are two well-studied drug transporters which are associated with MDR. These two transporters also act as a major functional unit of the blood brain barrier to protect the brain from xenobiotics and toxins. Lack of clinically approved P-gp and BCRP inhibitors renders chemotherapy treatments of many MDR cancers ineffective and obstructs drug uptake into the brain.

Using computational methods, we have identified new compounds that inhibit P-gp (Brewer et al., Mol. Pharmacol. 2014). Several of …

A Mechanistic Study Of The Teratogenic Potential Of 4-O-Methylhonokiol (Mh) On Japanese Medaka (Oryzias Latipes), Santu Kumar Singha

Electronic Theses and Dissertations

An additional goal of this project was to characterize the Wnt/β-catenin signaling pathway to unravel the adverse potential of MH on the cardiovascular system (CVS). Our study suggested that MH-mediated cardiovascular injury may be caused due to upregulation of some major components of the Wnt/β-catenin pathway through expression of excessive pro-inflammatory mediators. Moreover MH decreased expression of ErbB3 and NRG-2 suggesting impaired cardiac structure. MH exposure caused a slow heartbeat blood occlusion absence of blood circulation decreased hatching efficiency and increased mortality in medaka embryos in a concentration- and time-dependent manner. MH might cause blood vessel occlusion by increasing the …

Elucidation Of The Molecular Mechanisms Of Electrically-Induced Cardioprotection, Anne Elizabeth Roessler

Dissertations

Cardiovascular disease is the leading cause of death worldwide. A myocardial infarction (MI), commonly known as a heart attack, is a major event in cardiovascular disease characterized by reduced blood flow to the heart. The ischemia and reperfusion (I/R) injury associated with an MI results in a region of dead tissue in the heart called an infarct, the size of which influences patient prognosis. In the 1980s, it was discovered that short, non-lethal episodes of I/R, termed ischemic preconditioning (IPC), can protect the heart against a subsequent MI. Ischemic preconditioning demonstrated the phenomenon of endogenous cardioprotection. Cardioprotection has great potential …

Kinetics Of Microvesicle Particle Release In Keratinocytes, Pariksha Thapa

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Microvesicle particles (MVPs) are subcellular particles that could be involved in inter-cellular communication because they carry various bioactive substances including cytokines. Previous studies from our lab has shown that that the lipid mediator Platelet-activating Factor (1-alkyl-2-acetyl-glycerophosphocholine; PAF) and ultraviolet B radiation (UVB) enhances the release of MVP in various cell types like primary keratinocytes, epithelial cell lines, and murine skin. We hypothesized that there may be synergistic increases in MVP release after combination of treatment of keratinocytes with UVB and PAF agonist (CPAF)/phorbol ester (PMA). The combination treatment significantly increases MVP and cytokine release at 4 to 8 hours time …

Implementing Mass Spectrometry For The Structural And Compositional Analysis Of Proteins, Mohammad Riaz

Electronic Theses and Dissertations

Lectins are sugar-binding proteins that perform various biological functions such as cellular recognition attachments etc. Pulses the dried edible seeds of certain plants are great sources of lectins and a proteomics approach directed at lectins identification would bring substantial improvement in the lectin identification process. Lectins from nine different plant species were analyzed through SDS-PAGE and proteomics analysis. After LC-MS/MS analysis proteins were identified with protein database searches using Uniprot. Functionally uncharacterized proteins were identified with database searches were annotated with the Pfam and NCBI-CCD databases. In-vitro pharmacological screening will be carried out to assess the pharmacological effects of these …

Differing Functions Of Atr Kinase In Human Epidermal Keratinocytes Exposed To Ultraviolet B Radiation, Kavya Shaj

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Ataxia-telangiectasia and Rad-3 related (ATR) is a DNA damage response protein kinase that is upregulated in various cancer cell types and has key roles in cell cycle progression, DNA repair and apoptosis. Small molecule ATR kinase inhibitors are of importance as antineoplastic agents because they sensitize cancer cells to DNA damaging chemotherapy drugs. However, only a few studies have looked at the effects of ATR kinase inhibitors on non-replicating cells, which constitute the majority of cells in the human body and have suggested an opposite, pro-apoptotic role for ATR kinase signaling in non-replicating cells in comparison to a pro-survival function …

Effect Of Endothelial Progenitor Cell-Derived Exosomes On High Glucose And Hypoxia/ Reoxygenation-Induced Injury Of Astrocytes, Manasi Suchit Halurkar

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In this study, we tested the protective effects of EPC-EXs (endothelial progenitor cell derived exosomes) and miR-126 EPC-EXs (microRNA-126 EPC-EXs) on the astrocytes injured by HG (high glucose) plus H/R (hypoxia/reoxygenation) model. At first, we determined the concentration and time dependent uptake of EPC-EXs by astrocytes. It was also found that the EPC-EXs were uptaken via macropinocytosis, caveolin-dependent and clathrin-mediated pathways in astrocytes. Furthermore, the astrocyte cell line was injured through the HG + H/R model. EXs, isolated by ultracentrifugation from the EPC culture supernatant were co-incubated with the injured cells. It was found that EPC-EXs and miR-126 EPC-EXs decrease …

Evaluating The Aryl Hydrocarbon Receptor As A Target For Pharmacologic Activity Of Repurposed Drugs, Teofilo Borunda Duque

Pharmaceutical Sciences ETDs

The discovery of new pharmacologic targets is important for the advancement of pharmacotherapy and identification of new indications for current drugs. The aryl hydrocarbon receptor (AHR) is a physiologic sensor of both chemical environmental pollutants and ligands of natural origin. Given the broad spectrum of ligands that activate the AHR and its relationship with toxicology, the AHR is not thought to be a traditional target for pharmacotherapy. However, multiple studies have shown potential for the AHR as a novel pharmacologic target Therefore, identifying less toxic agents that modulate the AHR may elucidate mechanisms for pharmacological targeting of the AHR. The …

Protein Participants Of Cytosolic Internalization Of The Ouabain-Bound Na⁺/K⁺Atpase Receptor In Human B-3 Lens Epithelial Cells, Joshua Lysle Stricker

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The primary function of Na⁺/K⁺ATPase (NKA) discovered by Jens Christian Skou in 1958, through electrogenic exchange of 3 Na⁺ for 2 K⁺ ions (Robert L Post, 1958), is the homeostatic preservation of their electrochemical gradient across the plasma membrane (PM) of almost all species and their derived cell lines. Cardiotonic steroids (CTS), such as cardenolides or bufadienolides, are well established inhibitors of NKA. Fox glove plant extracts containing CTS, including digitalis, were first described by William Withering (1744-91) for their positive inotropic effect in heart failure patients. Later research identified the mechanism of their action through direct inhibition of NKA …