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Alternative Treatment of Hodgkin’s Lymphoma in a Patient with Severe Hepatic ImpairmentTorrence, A. M., Bossaer, John B. 01 December 2013 (has links)
No description available.
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Patient Use of Herbal Supplements in an Outpatient Hematology/Oncology Medical ClinicThomas, C. M., Bossaer, John B. 01 March 2012 (has links)
Primary Objective: According to the National Center for Health Statistics, many Americans use some type of vitamin or supplement. A recent study of cancer patients in the VA medical system found that a significant number of cancer patients do not mention the use of supplements to their healthcare providers. Many of these supplements were also found to interact with or compound side effects of chemotherapy regimens. The purpose of this study is to determine the incidence of cancer patients taking supplements and to determine the completeness of home medication lists in regard to vitamins or herbal supplements.
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Naloxone: The State of Co-Prescribing and Co-DispensingHagemeier, Nicholas E. 16 February 2018 (has links)
No description available.
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Applying Patient-Centered Care in Pain ManagementHagemeier, Nicholas E., Price, Elvin T. 17 March 2018 (has links) (PDF)
Learning Objectives: Describe the concept of patient ‐centered care from the pharmacist’s perspective. Summarize the science of patient ‐centered communication in pain management. Describe pharmacogenetic tests that are available to guide the use of opioids in pain management. Discuss research opportunities related to patient ‐centered care and genetic testing in pain management. Describe strategies used by pharmacists to implement genetic testing in clinical pharmacy practice.
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Crystallographic and spectroscopic assessment of pharmaceutical material mechanicsSingaraju, Aditya Bharadwaj 01 December 2018 (has links)
Despite the advent of alternative dosage forms, solid dosage forms constitute a major proportion of dosage forms not only on the market, but also in many pharmaceutical companies’ pipelines. This is because of their superior stability and ease of manufacturing relative to other dosage forms. Although solid dosage forms have been the topic of discussion for decades, the process of compaction of these dosage forms is considered an art rather than science because of the empiricism that exists in this area. With the introduction of Quality by Design (QbD), it is imperative that the drug development process is guided by structured scientific principles. It has been hypothesized that crystal structure of organic solids plays a pivotal role in understanding the properties, processing and eventually performance of solids. In this regard, the intermolecular interactions within a solid play a paramount role in dictating the materials response to stress. One important parameter that is weakly addressed in the literature is the concept of strength of intermolecular interactions. In the current work, we utilize the concept of elasticity as a metric for strength of intermolecular interactions. We introduce powder Brillouin light scattering; an inelastic light scattering technique to measure the elasticity of organic solids and try to correlate the mechanical moduli extracted from the spectra to the compaction performance of solids. We hypothesize that any redistribution of intermolecular interactions would be reflected in the BLS spectrum of these materials and the material properties can be used to explain the differences in compaction performance. Before we tested our hypothesis, we validated our powder BLS technique using aspirin as model system. We then applied the same analysis to four model systems that involved different ways of reorganizing the intermolecular interactions upon subtle modifications to the molecular structure.
In Chapter 4, we investigated the effect of alkyl chain length and crystal structure on the mechanical properties and compaction performance of p-aminobenzoic acid (PABA) and its esters. For the entire ester series, a similar hydrogen bonding pattern was observed with strong N-H…O (carbonyl) and supportive N-H…N interactions. While the ethyl and butyl esters exhibited a layered structure, the methyl ester displayed a 3-D isotropic structure. The crystal structure for PABA exhibited a three-dimensional, quasi-isotropic distribution of the hydrogen-bonding interactions that connected the PABA dimers. The powder BLS spectra for these materials revealed low velocity shear modes for the layered structures and a spectrum consistent with an isotropic structure for Me-PABA and PABA. This was in good agreement with the compressibility behavior under load, with Et-PABA and Bu-PABA more compressible than PABA. However, due to greater particle-particle adhesion, PABA compacts showed greater tensile strength at higher pressures. The moduli calculated also showed that both Et-PABA and Bu-PABA had lower shear and Young’s modulus relative to the other materials. Attachment energies corroborated the above results. These studies showed that weak dispersive forces play an important role in understanding material properties.
In Chapter 5, a series of nitrobenzoic derivatives were used to study the effect of secondary interactions on the crystal reorganization and material properties. The materials used in the study include p-nitrobenzoic acid (4-NBA), m-nitrobenzoic acid (3-NBA, 4-chloro-3-nitrobenzoic acid (Cl-NBA), 4-bromo-3-nitrobenzoic acid (Br-NBA), and 4-methyl-3-nitrobenzoic acid (Me-NBA). Crystal structures of the materials revealed different organization of C-H…O interactions. Two types of C-H…O interactions were prevalent namely C-H…O (nitro) and C-H…O (carboxy). The reorganization of these two types of interactions led to different packing motifs and different mechanical behavior. These structural features were reflected in their mechanical properties assessed by powder Brillouin light scattering. Cl-NBA and Br-NBA displayed an isotropic spectrum similar to polystyrene and aspirin. 3-NBA, 4-NBA and Me-NBA displayed different spectra from Cl-NBA and Br-NBA with high frequency tailing in the longitudinal mode distribution indicating a specific direction of extended molecular interactions. The Young’s modulus and shear modulus followed the order: 3-NBA < Me-NBA< 4-NBA < Cl-NBA < Br-NBA. The maximum longitudinal modulus Mmax was the highest for 3-NBA and was significantly greater than rest of the materials. From the compaction studies, it was observed that the tabletability followed the rank order 3-NBA > 4-NBA > Me-NBA ≈ Br-NBA ≈ Cl-NBA which is the same order as Mmax. 3-NBA by virtue of its low shear and Young’s modulus to be the most compressible material, but the compressibility rank order was 4-NBA > Me-NBA ≈ 3-NBA > Cl-NBA > Br-NBA. However, 3-NBA by virtue of its greater particle-particle adhesion was the most compactable material. The yield pressures obtained from Heckel plots revealed that 4-NBA and Me-NBA were relatively more plastic when compared to the other materials. This study demonstrated that subtle changes to the molecular structure can result in drastically different crystal packing which in turn would influence the mechanical properties and the compaction performance of organic solids.
In Chapter 6, we investigated the effect of cocrystallization on the compaction performance of caffeine(CAF). The series of halo-nitrobenzoic acids (F-NBA, Cl-NBA and 3-NBA) were used as coformers. The cocrystals CAF: F-NBA, CAF: Cl-NBA and CAF: NBA Form 1 adopted a flat layered structure that can undergo deformation with ease. This increased the compressibility of the cocrystals relative to CAF. In addition to the improved compressibility, by virtue of increased particle-particle contacts, the cocrystals also displayed superior tabletability. In contrast to the layered structures adopted by the three cocrystals, the CAF: NBA Form 2 displayed a columnar structure that exhibited resistance to stress. The compressibility and the tabletability of CAF: NBA Form 2 was significantly compromised when compared to that of Form1. All the compaction characteristics of the cocrystals were in good agreement with moduli and parameters obtained from powder BLS spectra. The layered materials showed the presence of low velocity shear modes corroborating the earlier studies. There was a clear difference in the spectra of the polymorphs, indicating that powder BLS can be used for mechanical screening of polymorphs.
In Chapter 7, we examined the effects of crystal structure and coformer functionality on the compaction performance of theophylline (THY). The coformers employed include 4-fluoro-3-nitrobenzoic acid (FNBA), acetaminophen (APAP), and p-aminobenzoic acid (PABA). While THY-APAP and THY-FNBA exhibited layered structures, the THY-PABA displayed a interdigitated columnar structure. Powder BLS spectra showed the presence of low frequency shear modes relative to THY for all the three cocrystals. However, the order of frequencies followed: THY-FNBA < THY-APAP < THY-PABA. The shear modulus calculated followed the order THY-APAP≈ THY-FNBA < THY < THY-PABA which is in agreement with the crystal structures discussed. The Young’s modulus followed the order THY-FNBA < THY-APAP < THY < THY-PABA. The two layered structures (THY-APAP, THY-FNBA) showed distinct compaction performance (similar compressibility but different compactability and tabletability). The layered structures were more compressible than THY which is hypothesized to undergo deformation through multiple mechanisms. THY-PABA showed poor compaction properties. This highlights the fact that although the coformer (PABA) is molecularly similar to FNBA, the resultant cocrystals are structurally and mechanically distinct. These observations were well supported by the moduli calculated from powder BLS studies. The order of yield pressures obtained from Heckel analysis followed the same order as shear modulus. The tensile strength of the compacts of the cocrystals level off at around 150 MPa but the tensile strength of THY compacts continues to increase. From a manufacturing perspective the cocrystals can prove to be a better option as they as more compactable at higher porosities or they possess greater tabletability at low compaction pressures.
Overall, we have used model systems to demonstrate that the redistribution of intermolecular forces upon point substitution or cocrystallization have a dramatic effect on the material properties. It is also worth noting that elasticity along with plasticity can provide important information about the strength of interactions which would help in understanding the role of weak intermolecular forces in the performance of organic materials. To gain a better perspective of the compaction process and move towards a QbD approach, it is also imperative to understand the link between crystal structures, intermolecular interactions which is possible with the help of novel characterization techniques (BLS, AFM).
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Mechanistic studies of cocrystal dissolution behaviorLee, Hong-Guann 01 May 2015 (has links)
The objective of this study is to investigate cocrystal solubility and dissolution behavior to elucidate the factors affecting these processes in various media. Six cocrystals with xanthines (theophylline (THP), caffeine (CAF) and theobromine (THB)) were prepared and characterized by powder X-ray diffraction and thermal methods. Two cocrystals (CAFCA I and THBSA) are new solids and their crystal structures were determined by single crystal X-ray diffraction.
Cocrystal solubility behavior depended on the dissolving complex solubility and its dissociation behavior in solution. Two THP cocrystals - one with acetaminophen (ACE) and one with citric acid (CA) created different degrees of free THP supersaturation in solubility and dissolution studies. High transient THP supersaturation caused almost immediate THP hydrate crystallization from THPCAH and led to non-congruent solubility behavior. Such behavior was not observed with the ACETHP because free THP supersaturation was not sufficient to induce rapid crystallization but did so over longer equilibration times.
Three salicylic acid (SA) cocrystals with xanthines (THP, CAF, and THB) were prepared; two (THPSA and CAFSA) had low aqueous solubility compared to their pure components and one (THBSA) had higher solubility. Both cocrystal components in these cocrystals produced higher solubility/dissolution rates in alkaline media due to ionization. Also, at higher pH, THB precipitated from THBSA solutions because of higher THB supersaturation under alkaline conditions.
Caffeine (CAF) and theophylline (THP) both form cocrystals with citric acid (CA) which is a highly water-soluble cocrystal former. Both CAFCA Form I and II solubility and dissolution behavior were studied. THPCAH exhibited non-congruent dissolution because of rapid precipitation of THP hydrate on the dissolving cocrystal surface. CAFCA exhibited congruent dissolution because it did not produce sufficient supersaturation to precipitate CAF hydrate during dissolution. CA cocrystals also have the unusual behavior of high viscosities produced in the dissolution boundary layer due to CA’s high solubility. These viscosities alter diffusion coefficients which reduce dissolution rates from that expected based purely on solubility.
To further understand cocrystal dissolution, a diffusion-convection-reaction (DCR) model was developed to predict cocrystal dissolution rates in various media. This model predicted concentration profiles of all species (complex, free components and reactive species) in the diffusion layer of a rotating disk intrinsic dissolution system. Predicted dissolution rates had varying degrees of agreement with experimental data depending on the cocrystal model and the medium into which the cocrystal dissolved.
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Investigation of the effects of curing and casting methods on the physicochemical properties of polymeric coating systemsLi, Yingjian 01 December 2016 (has links)
This study is to evaluate the effect of curing and casting methods on the physicochemical properties of polymeric coating systems. Aqueous-dispersion-based and organic-solvent-based Kollicoat® SR30D (poly(vinyl acetate)) and Kollicoat® MAE100P (poly(methacrylic acid-ethyl acrylate)) free films or film-coated pellets were used to evaluate the physicochemical properties resulting from different solvents and different curing treatments.
Diffusion coefficients of water in organic-solvent-based films were lower than those in aqueous-dispersion-based films. Increases in curing temperature and curing time decreased the diffusion coefficient. Regardless of preparation method, the tensile strengths of films increased with an increase in curing temperature and curing time. Changes in elongation percentage of the films were dependent on the polymer and curing. The tensile strengths of aqueous-dispersion-based SR30D films are lower compared to those of organic-solvent-based SR30D films. However, the “core-shell” structure is preserved in the aqueous-dispersion-based MAE100P film and formed a rigid frame, which greatly increased the mechanical properties of the films. Therefore, the tensile strength of aqueous-dispersion-based MAE100P films is greater than in the case of organic-solvent-based films. In swelling studies, water uptake and weight loss for all of the films increased with an increase in incubation time. The water uptake and weight loss of SR30D films cast from water were higher than those of organic-solvent-based films. However, contradictory results were observed for MAE100P films due to the core-shell structure in the aqueous-dispersion-based MAE100P films. An increase in curing time and temperature increased the Tg of SR30D films. Curing treatments led to a second glass transition temperature for MAE100P films, which may result from microphase separation.
Curing decreased acetaminophen release from pellets coated with an aqueous-dispersion-based SR30D film. Curing effects are also dependent on the coating formulation and coating parameters. The drug release rate from organic-solvent-based film-coated pellets was slower in comparison to pellets coated with aqueous-dispersion-based films. Acetaminophen release in 0.1 N HCl from aqueous-dispersion-based MAE100P coated pellets was reduced after the curing treatment. Curing has no effect on drug release for acetaminophen-containing pellets coated with organic-solvent-based SR30D or MAE100P films.
The ionization of surface carboxylic-acid groups on MAE100P polymer particles alters the properties of polymer films by increasing ionic aggregates and solubilizing the polymer chains. Increased ionic aggregates improve the mechanical properties of films. However, solubilizing polymer chains will change the film formation mechanism from a dispersion-based film to a solution-based film. Therefore, tensile strength was decreased with an increase in ionization degree. The drug release rates were continuously increased when the degree of ionization of surface acid groups increased.
Overall, curing and casting methods have significant effects on the physicochemical properties of SR30D and MAE100P films and on the drug release behavior from film-coated, drug-loaded pellets. The core-shell structure in aqueous-dispersion-based MAE100P films also greatly changed the properties of this film or coat.
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Endogenous and exogenous modulation of regulator of G-protein signaling 4Monroy, Carlos Aaron 01 July 2013 (has links)
Regulators of G-protein signaling (RGS) proteins are a family of proteins that act as GTPase accelerating proteins (GAPs) through their interaction with GΑ subunits, including GΑo, GΑi, and GΑq but not GΑs. This increased rate of hydrolysis of GTP to GDP temporally regulates G-protein coupled receptor (GPCR) signaling. A member of this family, RGS4, has been implicated in several neurological disorders including Parkinson's Disease (PD). A hallmark of PD is the induction of oxidative stress within dopaminergic neurons. In this thesis, we evaluate the role of oxidative stress, including lipid peroxidation products with 4-hydroxy-2-nonenal (4HNE) as a model, in regulating RGS4 activity within neurons. Utilizing transfected RGS4, we evaluated whether RGS4 is readily modified by physiologically relevant concentrations of 4HNE by immuonoprecipitation of RGS4 from 4HNE treated cells. Further examination of recombinant RGS4 by mass spectrometry, revealed that RGS4 is readily modified at several cysteine residues by 4HNE, including C148. Modification at this residue has been shown to be a critical site for allosteric regulation of RGS4. This is confirmed through a malachite green based phosphate generation assay we developed to observe the GAP activity of RGS4 on its native binding partner GΑi. This malachite green based assay was then adapted for high throughput screening. The assay was successfully miniaturized to a 1536-well format. In a screen of 2300 compounds, 4 were identified as hits. The development of this simple and cheap assay can be adapted for usage with a variety of RGS proteins with little work to interrogate other pathways and identify novel RGS modulators.
Finally, expansive study of PD has linked oxidative stress to the pathology of both diseases. What has not been discerned is the potential relationship between oxidative stress and the induction of RGS4. In support of the hypothesis, we evaluated the potential relationship between oxidative stress and RGS4 expression. This was accomplished by evaluating two striatal neuron like cell lines, SH-SY5Y and HCN-1A. After treatment with hydrogen peroxide, both cell lines showed increased RGS4 in response to oxidative stress. This response is not however related to mRNA expression, indicating this change is most likely an adjustment of proteasomal regulation of RGS4. This phenomenon may explain the rapid onset of Parkinsonian motor symptoms in reserpine treated animal models of PD, as excess dopamine in the cytoplasm may be rapidly metabolized in reactive products.
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Investigating the effects of structural modification of alkyl triphenylphosphonium compounds on mitochondrial uncoupling and accumulationKulkarni, Chaitanya Aniruddha 01 August 2017 (has links)
Mitochondria are organelles present in eukaryotic cells that play a key role in regulating cells’ metabolic processes as well as cell death. The main function of mitochondria is to produce ATP, by oxidizing nutrients in a process called oxidative phosphorylation (OXPHOS). Besides this, mitochondria also play a critical role in calcium homeostasis, cell signaling, and apoptosis. Mitochondrial dysfunction is implicated in a plethora of diseases including neurodegenerative diseases, metabolic disorders as well as ageing and cancer.
The triphenylphosphonium (TPP+) moiety has been used as a carrier to direct a wide variety of therapeutic and diagnostic cargo to mitochondria, in an effort to study and treat mitochondrial dysfunction. Studies in recent years show that TPP+ is not an inert carrier as previously thought. Many TPP+ conjugates have been shown to exert a negative effect on mitochondrial and cellular bioenergetics by decreasing the efficiency of OXPHOS. This phenomenon is called ‘mitochondrial uncoupling’. While mitochondrial uncoupling is undesirable for the TPP+ moiety to function as a carrier of cargo to mitochondria, controlled uncoupling has therapeutic applications in treatment of obesity and cancer.
The extent of mitochondrial accumulation as well as potency of mitochondrial uncoupling caused by the TPP+ moiety increases with increasing length of the linker functionality in TPP+ conjugates. Most of the studies to date have focused on altering the linker length of the TPP+-linker-cargo conjugate to optimize the balance between safety and efficacy. However, very little is known about how structural modification of the TPP+ moiety itself affects mitochondrial uncoupling potency. Therefore, there is a need to understand the structure activity relationship (SAR) between modification of TPP+ structure and the effect of these structural changes on mitochondrial uncoupling and uptake.
Towards this end, the first goal of this study was to understand the effect of modulating electron density on the phosphorus atom of TPP+ on the potency of uncoupling OXPHOS. Modifications to the TPP+ moiety included substitution of electron withdrawing and donating groups on the phenyl rings of TPP+, and replacing phenyl rings with bulkier napthyl rings. Modified TPP+ moieties were conjugated to five different linkers, which varied in length and lipophilicity, and the effect of these conjugates on mitochondrial bioenergetics was studied.
The second goal of the study was to evaluate if the propensity of TPP+ to uncouple mitochondrial respiration can be modulated, independently of mitochondrial uptake. For this purpose, the uptake of modified TPP+-linker conjugates into isolated mitochondria and the uptake of fluorescently labeled modified TPP+-linker conjugates into mitochondria within whole cells was investigated. The ability of modified TPP+ to protect cells from oxidative stress by successfully delivering an anti-oxidant cargo to mitochondria within cells was also assessed.
The results of these studies establish the first SAR for modulating TPP+ structure to either eliminate, optimize, or maximize uncoupling of mitochondrial OXPHOS, and led to identification of lead molecules for potential applications in the fields of mitochondrial delivery, anti-obesity therapy and anti-cancer therapy.
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The potential disruption of estrogen and androgen homeostasis and adipocyte differentiation by metabolites of common airborne polychlorinated biphenylsParker, Victoria Shayla 01 May 2019 (has links)
Polychlorinated biphenyls (PCBs) are persistent, man-made toxicants that are linked to adverse health effects and diseases such as endocrine disruption, diabetes, obesity, cardiovascular effects, and cancer. Since their manufacturing began in 1929 for industrial use, and was banned in 1979, they have bioaccumulated in water, sediment, food, animals, humans and more. PCBs are also found in indoor air of older buildings and as inadvertent byproducts in the manufacture of paints and pigments. The lower chlorinated PCBs, those with fewer than 5 chlorine atoms, are readily metabolized to form hydroxylated PCBs (OH-PCBs) that are further converted to PCB-sulfates in reactions catalyzed by cytosolic sulfotransferases (SULTs).
Steroid sulfotransferases SULT1E1 and SULT2A1 participate in regulating the homeostasis of estrogens and androgens, respectively, through the deactivation of active hormones. The estrogen sulfotransferase (SULT1E1) is also a potential key player in adipogenesis. Recent literature has shown that downregulating expression of SULT1E1 in cells derived from humans and mice caused opposite effects, where adipogenesis was inhibited or stimulated, respectively. Adipogenesis is the maturation of preadipocytes into mature adipocytes, which is regulated by peroxisome proliferating-activator γ (PPARγ). Adipocytes are a main component of adipose tissue, which is important for energy homeostasis, organ protection, and thermoregulation. Adipose tissue also secretes various cytokines such as adiponectin. Adipose tissue dysfunction can result from adipocyte dysfunction, which can be caused by alterations in cell signaling.
The objective of this dissertation research was to determine if OH-PCBs and PCB-sulfates are inhibitors of SULT1E1 and SULT2A1 and if inhibition of SULT1E1 by OH-PCBs could potentially affect adipogenesis. We hypothesized that PCB metabolites would inhibit SULT1E1 and SULT2A1 and potentially affect adipogenesis in both human and murine cell models.
Using purified recombinant human SULT1E1 and SULT2A1, I found that 4’-OH-PCB 3, 4-OH-PCB 8, 4-OH-PCB 11, 4’-OH-PCB 25, and 4-OH-PCB 52 were potent inhibitors of the sulfation of representative substrates (7.0 nM estradiol for SULT1E1 and 1.0 µM dehydroepiandrosterone for SULT2A1, Figures 3-3 and 3-4, respectively). Moreover, 4-OH-PCB 11 and 4-OH-PCB 52 were the most potent inhibitors of SULT1E1 and SULT2A1 with IC50 values of 7.2 nM and 1.5 μM, tables 3-1 and 3-2, respectively. The least potent inhibitor of SULT1E1 was 4’-OH-PCB 3, with an IC50 of 1300 nM. The PCB-sulfates were not potent inhibitors for either enzyme. 4-OH-PCB 11 inhibited the sulfation of estradiol in the cytosol of both pre-adipocytes and fully differentiated adipocytes (Figure 4-9).
Immortalized human adipocytes were treated with 10 µM of triclosan (a known inhibitor of SULT1E1), 4’-OH-PCB 3 and 4-OH-PCB 11. Experiments included exposure to these toxicants for 1) 72 hours to preadipocytes, 2) 72 hours to preadipocytes followed by 11-day differentiation, 3) to differentiating adipocytes and for 48 hours post-differentiation. The lipid accumulation levels remained unaffected, as determined by microscopic imaging and quantification using AdipoRed. The mRNA expression levels of prominent adipogenic markers SULT1E1, PPARγ, and AdipoQ were measured using RT-Q-PCR. Changes in SULT1E1 and PPARγ expression were unaffected upon treatment before, during and after adipogenesis when compared to controls. However, the increase in AdipoQ expression was reduced upon treatment with 4-OH-PCB 11 in differentiated adipocytes and in preadipocytes exposed for 72 hours followed by 11-day differentiation (Figure 4-14). This could be an indicator of adipocyte dysfunction that was not manifested by a change in lipid accumulation.
Murine 3T3-L1 cells were also treated with 10 µM of triclosan, 4’-OH-PCB 3 and 4-OH-PCB 11 for 48 hours to preadipocytes, during 8-day differentiation and for 48 hours after differentiation. The mRNA expression levels of prominent markers of cardiovascular and adipogenesis functions, ACE2, PPARγ, FABP4, and AdipoQ were measured using RT-PCR. Compared to controls, the increase in AdipoQ expression was reduced following treatment of preadipocytes with triclosan and 4-OH-PCB 11 and subsequent differentiation (Figure 5-11). The increase in PPARγ expression remained either unchanged from controls or slightly stimulated in differentiating and differentiated adipocytes (Figures 5-11 and 5-13). Angiotensin-converting enzyme 2 (ACE2) expression was decreased compared to control values, upon treatment with 4’-OH-PCB 3 (Figure 5-12), while fatty acid binding protein 4 (FABP4) expression was stimulated to the same extent across all treatment groups in differentiating adipocytes (Figure 5-12).
The results, overall, show that these OH-PCBs did not affect lipid accumulation in human adipocytes, but they may affect other signaling pathways in adipogenesis. 4-OH-PCB 11 decreased adiponectin expression compared to the increase that was seen in unexposed differentiating human and mouse adipocytes. Adiponectin is secreted from adipose tissue, and this decrease could indicate a form of dysfunction. This finding is consistent with the results of the purified SULT1E1 study, where 4-OH-PCB 11 potently inhibited SULT1E1, but 4’-OH-PCB 3 did not (Figure 3-3 and Table 3-1). Thus, there is a potential for OH-PCBs to disrupt the expression of adiponectin and perhaps other vital adipokines and this could negatively affect adipose tissue function. Future studies will be needed to determine if these effects are indeed mediated by intracellular estradiol and SULT1E1. Moreover, the potential for in vivo disruption of circulating adiponectin by OH-PCBs and other toxicants that inhibit SULTs remains to be studied.
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