Medicine and Health Sciences Commons^™

Cannabinoids And Retinal Fibrotic Disorders., Lucy June Sloan

Electronic Theses and Dissertations

Retinal fibrosis is detrimental to vision. Retinal pigment epithelial (RPE) cells contribute to several retinal fibrotic diseases. Upon exposure to TGF-β, a key fibrotic cytokine, RPE cells trans-differentiate to myofibroblasts marked by the integration of α-SMA fibers into F-actin stress fibers, which confer strong contractility. Myofibroblasts produce and contract the collagen-rich fibrotic scar and disrupt retinal architecture. In this study, we investigated the in vitro effects of the putative endocannabinoid compound N-oleoyl dopamine (OLDA) on TGF-β2 induced porcine RPE cell contraction and α-SMA expression. Using an in vitro collagen matrix contraction assay, we found that OLDA inhibited TGF-β2 induced contraction …

N-Acetyltranserase 2 (Nat2) Genotype Polymorphism In Cryopreserved Human Hepatocytes And Chinese Hamster Ovary (Cho) Cells., Mariam Refaat Zaky Habil

Electronic Theses and Dissertations

Arylamine N-acetyltransferases, NAT1 and NAT2, catalyze the detoxification and/or activation of drugs and aromatic amine carcinogens. Single nucleotide polymorphisms or SNPs result in different human NAT2 genotypes thus dividing the population into rapid, intermediate, and slow acetylators. We hypothesize allelic variants of NAT2 genotype will decrease levels of N-acetylation, cytotoxicity, oxidative stress, DNA adduct formation, and mutagenesis compared to the reference allele NAT2*4. Cryopreserved human hepatocytes expressing different NAT2 genotypes and NER-deficient Chinese hamster ovary (CHO) cells transfected with human CYP1A2 and human NAT2*4, NAT2*5B or NAT2*7B have been used to investigate N-acetylation of different xenobiotics. In …

Human Genetics, Psychotropic Drugs, And Acts Of Violence, Selma Jolanda Eikelenboom-Schieveld

Electronic Theses and Dissertations

From the start of the use of psychoactive prescription medications in the 1950s, physicians reported paradoxical adverse reactions, ranging from newly developing depressions to an increase in existing mood disorders, and extremely violent and bizarre acts of suicide and homicide. In this research, it is hypothesized that the pharmacological properties of the prescribed drugs or the interaction between the drugs and the enzymes that are primarily responsible for their metabolism (cytochrome P450s) could cause these reactions. Given that acts of violence could be medication-induced, the role of the rate of drug metabolism is discussed. Genetic testing of certain CYP450s could …

Dual Inhibition Of The Pi3k/Akt And Mek5/Erk5 Pathways For The Treatment Of Breast Cancer, Thomas Douglas Wright

Electronic Theses and Dissertations

Breast cancer is a heterogeneous disease state with several challenging frontiers. In particular, aberrations in the Phosphoinositide-3-kinase (PI3K) and Mitogen Activated Protein Kinase (MAPK) pathways have been linked to increased breast cancer proliferation and survival. It has been proposed that these survival characteristics are enhanced through compensatory signaling and crosstalk mechanisms. New evidence suggests that MEK5/ERK5, a member of the MAPK family, is a crucial component in the proliferation and survival of several aggressive cancers. We hypothesize that inhibiting both PI3K/Akt and MEK5/ERK5 pathways will decrease cell viability while maintaining limited collateral toxicity. In this study, we examined the effects …

Development Of Bar-Peptide Nanoparticles And Electrospun Fibers For The Prevention And Treatment Of Oral Biofilms., Mohamed Yehia Mahmoud

Electronic Theses and Dissertations

Background: Periodontal diseases are globally prevalent inflammatory disorders that affect ~47% of U.S adults. Porphyromonas gingivalis (Pg) has been identified as a “keystone” pathogen that disrupts host-microbe homeostasis and contributes to the initiation and progression of periodontitis. Pg associates with oral streptococci in supragingival plaque and this interaction represents a potential target for therapeutic intervention. Previously our group developed a peptide (designated BAR), that potently inhibits Pg/Streptococcus gordonii (Sg) adherence in vitro and Pg virulence in a murine model of periodontitis. While efficacious, BAR (SspB Adherence Region) provided transient inhibition and required higher concentrations of BAR to disrupt established …

Development Of A Lectin-Fc Fusion Protein With Antiviral And Anti-Cancer Activity., Matthew William Dent

Electronic Theses and Dissertations

This thesis describes the development of a novel lectin-Fc fusion protein and its antiviral and anti-cancer activity. The molecule, Avaren-Fc (AvFc), is a fusion of a variant of the actinomycete lectin actinohivin (Avaren) and the Fc region of human IgG1, and is selective for the terminal α1,2-mannose residues found at the ends of high-mannose-type glycans that can be found on the surface of certain heavily glycosylated viruses and cancer cells. Here, AvFc was found to be able to neutralize simian immunodeficiency virus as well as Hepatitis C virus with nanomolar IC₅₀ values. Furthermore, AvFc recognizes a number of cell …

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 …

Wnt/Β-Catenin Mediated Cancer Stem Cell Activation In Hepatocellular Carcinoma., Harshulkumar M. Pandit

Electronic Theses and Dissertations

Hepatocellular carcinoma (HCC) is one of the deadliest cancers, with variable presentation, high chemotherapy resistance and early tumor recurrence. In this dissertation, we have systematically enriched, identified and characterized HCC cancer stem cells (CSCs) from 3 different HCC cell lines (Hepa1-6, HepG2, and Hep3B) using in vitro serum-free culture method. Enriched spheroids acquired CSC properties, primarily self-renewal capability, spheroid formation ability, and drug resistance. Heterogeneous CSCs enriched from Hepa1-6 cells demonstrated higher tumor initiation and proliferation capability in vivo, compared to control HCC cells in orthotopic immunocompetent mouse model. EpCAM+ CSCs were significantly enriched within heterogeneous Hepa1-6 CSC spheroids. Consequently, …

A Novel Fibroblast Growth Factor 1 Variant Reverses Nonalcoholic Fatty Liver Disease In Type 2 Diabetes., Qian Lin

Electronic Theses and Dissertations

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder and is strongly associated with type 2 diabetes (T2D). Our recently engineered FGF1 partial agonist, carrying triple mutations (FGF1^△HBS) exhibits greatly reduced proliferative potential, while preserving the full metabolic activity of wild-type FGF1. This study tests the preventive and therapeutic effects of FGF1^△HBS on NAFLD in db/db T2D and explores potential mechanisms. The results showed that administration of FGF1^△HBS to 2-month-old db/db mice for 2 months constantly lowered blood glucose levels, improved insulin sensitivity, and lowered liver weight, lipid deposition, and …

Evaluation Of Drug-Loaded Gold Nanoparticle Cytotoxicity As A Function Of Tumor Tissue Heterogeneity., Hunter Allan Miller

Electronic Theses and Dissertations

The inherent heterogeneity of tumor tissue presents a major challenge to nanoparticle-medicated drug delivery. This heterogeneity spans from the molecular to the cellular (cell types) and to the tissue (vasculature, extra-cellular matrix) scales. Here we employ computational modeling to evaluate therapeutic response as a function of vascular-induced tumor tissue heterogeneity. Using data with three-layered gold nanoparticles loaded with cisplatin, nanotherapy is simulated with different levels of tissue heterogeneity, and the treatment response is measured in terms of tumor regression. The results show that tumor vascular density non-trivially influences the nanoparticle uptake and washout, and the associated tissue response. The drug …

Hiv Integrase Inhibitor Pharmacogenetics And Clinical Outcomes: An Exploratory Association Study, Derek E. Murrell

Electronic Theses and Dissertations

As HIV is now primarily a chronic condition, treatment is given life-long with changes as necessitated by alterations in tolerability and efficacy. Thus, personalized medicine may be useful in the prevention of unnecessary drug exposure and avoidable side effects. Three of the four currently available HIV integrase strand transfer inhibitors (INSTIs), raltegravir, elvitegravir, and dolutegravir, are widely utilized antiretrovirals in the USA and exhibit variations in outcomes among subjects. To interrogate differences among subjects receiving these drugs, we investigated the association of several single nucleotide polymorphisms (SNPs) with drug exposure, clinical outcomes, and subject-reported adverse events. HIV+ adults (≥18 years …

Melatonin-Micronutrients Osteopenia Treatment Study (Mots): A Translational Study Assessing The Effects Of Melatonin, Strontium Citrate, Vitamin D3 And Vitamin K2 On Bone Density, Bone Turnover Markers And Health-Related Quality Of Life In Postmenopausal Osteopenic Women Following A One-Year Double-Blind Randomized Placebo-Controlled Trial And On Osteoblast-Osteoclast Co-Cultures, Sifat Maria

Electronic Theses and Dissertations

Objective: The purpose of this study was to assess if a novel combination of melatonin and three other natural bone-aiding micronutrients: strontium citrate, vitamins D₃ and K₂ (MSDK) could improve bone health by modulating the activity of osteoblasts and osteoclasts in favor of balanced bone remodeling and by improving the overall health-related quality of life in postmenopausal osteopenic women.

Methods: The Melatonin-micronutrients Osteopenia Treatment Study (MOTS) is a translational research study that used both clinical and in vitro approaches to assess the efficacy of MSDK on bone health in women and to identify potential mechanisms for its effects. …

The Combined Neuropharmacology And Toxicology Of Major 'Bath Salts' Constituents Mdpv, Mephedrone, And Methylone, Serena Allen

Electronic Theses and Dissertations

The synthetic cathinones, 3,4- methylenedioxypyrovalerone (MDPV), 4-methylmethcathinone (mephedrone), and 3,4- methylenedioxymethcathinone (methylone), gained worldwide notoriety as the psychoactive components of ‘bath salts;’ a marketing term used to circumvent federal drug laws and permit their legal sale. Previous studies have shown that these drugs share pharmacological characteristics with cocaine and the amphetamines, however, descriptions of their neurotoxic properties are limited. Moreover, while forensic analysis has revealed that the most frequently abused bath salts ‘brands’ contain binary and ternary mixtures of MDPV, mephedrone, and methylone, the majority of preclinical research has focused on explicating the individual effects of these drugs. Therefore, the …

The Effects Of Polychlorinated Biphenyls Exposure On Non-Alcoholic Fatty Liver Disease : Role Of Aryl Hydrocarbon Receptor., Hongxue Shi

Electronic Theses and Dissertations

Polychlorinated biphenyls (PCBs) are detectable in serum of 100% of adults in US, and has been associated with fatty liver disease in epidemiological studies. PCBs are classified as either dioxin-like (DL) or non-dioxin-like (NDL) PCB based on their ability to activate the aryl hydrocarbon receptor (AhR). We used exposures that reflect human bioaccumulation patterns, which resembles Aroclor 1260 with a low level of the DL-PCB, PCB 126. Our aim was to determine if this exposure will activate the human and mouse AhR and examine if receptor activation influences these steatotic responses due to PCB exposures. DL-PCBs exposure-induced AhR activation in …

Role Of Microglial Α7 Nicotinic Acetylcholine Receptor Positive Allosteric Modulator In Neuroinflammatory Pain Models In Mice, Muzaffar Abbas

Electronic Theses and Dissertations

Neuroinflammatory pain affects about 1.5% of the United States population. Around 20-40% patients having neurological disorders are affected with neuroinflammatory pain. As a part of the limbic system, hippocampus is known to play a critical role in pain perception and processing, and is densely populated with microglial cells and α7 nicotinic acetylcholine receptors (nAChRs). Given the role of microglial α7 nAChRs in neuroinflammation, the α7 nAChRs have emerged as potential target for neuroinflammatory pain treatment. We hypothesized that microglial α7 nAChRs positive allosteric modulation in the hippocampus will decrease neuroinflammatory pain at behavioral, cellular, biochemical, and molecular level. The primary …

Mechanisms And Intervention Strategies For Alcohol And Hiv-Antiretroviral Therapy-Induced Liver Injury., Hridgandh Donde

Electronic Theses and Dissertations

Chronic alcohol consumption is a leading cause of liver disease and liver-related death worldwide. Alcoholic liver disease includes, hepatic steatosis, steatohepatitis and ultimately fibrosis and cirrhosis. Emerging evidence has established the important role of the “gut-liver” axis in the development of alcoholic liver disease (ALD). Our recent work indicated that chronic alcohol induced perturbations in the gut microbiome and consequent changes in fatty acids have a major impact on the development of intestinal barrier dysfunction and ALD. The aim of this study was to investigate whether treatment with tributyrin - a butyrate prodrug results in protection against ALD in terms …

Signaling Mechanisms For Muscarinic Receptor-Mediated Coronary Vasoconstriction In Isolated Rat Hearts, Yi Zhang

Electronic Theses and Dissertations

The signaling mechanisms for muscarinic receptor-mediated vasoconstriction in coronary resistance arteries were studied in KCl-arrested isolated rat hearts perfused at a constant flow rate. The cholinergic agonists acetylcholine and bethanechol were given by bolus injection or constant infusion. The coronary vascular resistance was monitored by measuring the changes in perfusion pressure. The selective muscarinic agonist bethanechol caused a similar vasoconstrictor response as ACh, but with less potency and efficacy. Bolus injection of bethanechol evoked a phasic vasoconstriction in a dose-dependent manner, while infusion of bethanechol evoked a tonic vasoconstriction without producing tachyphylaxis. Coronary vascular responses to bethanechol were further examined …

Comparison Of Beta-Adrenoceptor Coupled Camp Production In Cultured Human Mononuclear Leukocytes And Myometrial Cells, Yu-Li Liu

Electronic Theses and Dissertations

$\beta\sb2$-Adrenoceptor ($\beta\sb2$-AR) agonists, such as terbutaline, are used as tocolytic agents in the treatment of preterm labor. $\beta$-Adrenoceptor stimulation relaxes myometrium through specific receptors coupled through Gs to adenylyl cyclase (AC) that catalyzes the conversion of ATP to cAMP. The purpose of this study was to compare $\beta$-adrenoceptors and cAMP production in cultured human leukocytes and myometrial cells, and to determine the importance of $\beta$-adrenoceptors and cAMP production in isoproterenol-induced myometrial relaxation. $\sp{125}$I-iodopindolol was used to assess $\beta$-adrenoceptor affinity and number cAMP levels were analyzed before and after stimulation by isoproterenol, AlF$\sb4\sp-$, forskolin, and PGE$\sb1$. Isometric recording was used to …

Persistent Oral Dyskinesias Induced By Long-Term Haloperidol Treatment Is Dissociated From Changes In Neostriatal B(Max) And Mrna Content For Dopamine D(2) Receptors, Nuoyu Huang

Electronic Theses and Dissertations

Due to the presumed associations of dopamine (DA) receptor supersensitivity phenomena in both long-term neuroleptic-treated tardive dyskinetic rats and neonatal 6-hydroxydopamine (n6-OHDA)-lesioned rats, we studied the influence of haloperidol on n6-OHDA-lesioned rats. At 3 days after birth rats received 6-OHDA-HBr (200 $\mu$g, bilateral intracerebroventricularly; desipramine pretreatment, 20 mg/kg, 1h) or vehicle. Two months later haloperidol (1.5/kg/day $\times$ 2 days/week for 4 weeks, then 1.5 mg/kg/day, every day for 10 months) was added to the drinking water. Spontaneous oral activity of intact and n6-OHDA-lesioned rats receiving haloperidol was reached and maintained at significantly higher levels after 15 weeks of haloperidol treatment. …

Indomethacin Reduces Splenic Red Pulp Macrophage Populations In Female New Zealand White Rabbits, Thane S. Thurmond

Electronic Theses and Dissertations

In an effort to elucidate the mechanism by which indomethacin (IN) attenuates the stimulatory effect of estradiol (E$\sb2$) on rabbit splenic red pulp macrophages (RPM), thirty-nine female New Zealand White rabbits were divided into 10 groups: ovariectomized (OVX), OVX/IN at 0.1 and 5.0 mg/kg body weight (bw)/day; sham OVX (SOVX), SOVX/IN at 0.1 and 5.0 mg/kg bw/day; OVX/25 mg E2, OVX/25 mg E$\sb2$/IN at 0.1 and 5.0 mg/kg bw/day; intact Control. Quantitative changes in RPM population in response to the treatments were measured using a 0 to 4 histologic grading scale. Estradiol treatment resulted in increased RPM grade when compared …

Denervation Supersensitivity Of The Rat Vas Deferens: A Role For Protein Kinase C, Sonny T. Abraham

Electronic Theses and Dissertations

A role for protein kinase C (PKC) in the denervation-induced supersensitivity of the rat vas deferens was investigated. Chronic, surgical denervation of the rat vas deferens (up to 8 days) resulted in tissues that produced enhanced contractile responses to norepinephrine (NE) in isolated organ baths. Single challenges of NE (10 $\mu$M) produced 0.6 $\pm$ 0.1 g of maximal tension in the control vas whereas in the paired, denervated tissue 2.2 $\pm$ 0.3 g of tension was recorded (n = 6). Cumulative concentration-effect curves to NE produced in the denervated vas deferens were shifted 18-fold to the left of the control …

Differential Role Of The Endothelium In Regulating Microvascular Blood Flow, Tao Tang

Electronic Theses and Dissertations

The vascular endothelial cell (EC) plays an important role in regulating vascular tone and local blood flow by sensing chemical and mechanical stimuli on the vascular wall and releasing a host of vasoactive substances upon activations of endogenous or exogenous vasoactive substances. The central hypothesis is that local control of blood now and autoregulatory behavior in the microcirculation is distinctive at different levels of the vasculature and is dependent on the cellular activities of the EC and its interaction with the local environment. The in vivo as well as the ex vivo, flow-controlled preparations of the hamster cheek pouch were …

Characterization Of The Vasoactivity Of Tachykinins In Isolated Rat Kidney: Functional Studies And In Vitro Receptor Autoradiography, Yuejin Chen

Electronic Theses and Dissertations

Although tachykinins have potent vascular actions, their effect on renal resistance blood vessels is currently unknown. The vasoactive properties of tachykinins and related analogs were assessed in isolated perfused rat kidney. At a basal perfusion pressure (PP) of 75 $\pm$ 6 mm Hg (n = 5), bolus injections of substance P (SP) had no significant vasoactive effect. Following a sustained increase in baseline PP (134 $\pm$ 10 mm Hg) produced by phenylephrine (1 $\mu$M), SP evoked a dose-dependent increase in PP. The largest dose of SP increased PP by 60 $\pm$ 5 mm Hg. The vasoconstrictor response to SP was …

Co-Sensitization Of Dopamine And Serotonin Receptors Occurs In The Absence Of A Change In The Dopamine D1 Receptor Complex After A Neonatal 6-Ohda Lesion, Li Gong

Electronic Theses and Dissertations

To test whether SKF 38393 could ontogenetically sensitize dopamine (DA) D$\sb1$ receptors and whether this sensitization would be associated with biochemical changes, intact and neonatal 6-hydroxydopamine (6-OHDA)-lesioned rats (200 $\mu$g i.c.v.) were treated daily from birth with SKF 38393 (3.0 mg/kg i.p. x 28 days) or its vehicle. In DA D$\sb1$ neonatally sensitized 6-OHDA rats, enhanced locomotor responses were observed with the first SKF 38393 challenge dose (3.0 mg/kg i.p.) at 6 weeks. This response increased further with weekly SKF 38393 treatments. Enhanced stereotyped behaviors were seen in both lesioned and sensitized rats at 8 weeks. There was no change …