Personalized medicine can be an approach to address the unsatisfactory treatment outcomes in inflammatory conditions such as cancer, arthritis, and cardiovascular diseases. A common feature of chronic diseases is the infiltration of pro-inflammatory macrophages at the disease loci. Infiltrating macrophages have been previously utilized for disease diagnosis. These features suggest that macrophages can be broadly applicable targets for simultaneous therapy and diagnosis. Cyclooxygenase-2 (COX-2), an enzyme involved in the biosynthesis of a lipid inflammatory mediator, prostaglandin E2 (PGE2), is over expressed in macrophages infiltrating the pathological site. Inhibition of PGE2 leads to reduced inflammation, pain and macrophage infiltration. To utilize macrophages for the purpose of simultaneous therapy and diagnosis, we proposed to integrate therapeutic and imaging capabilities on a single nanomedicine platform, referred as theranostics. A stable 19F MRI visible nanoemulsion platform was developed, incorporating celecoxib for COX-2 inhibition and near-infrared fluorescent dye(s) for fluorescence imaging. We hypothesized that inhibition of COX-2 in macrophages using a theranostic nanoemulsion will reduce the inflammation (and pain), and that this response can be visualized by monitoring changes in macrophage infiltration. In vitro characterization demonstrated that the theranostic displays excellent stability with no toxicity, and significant uptake in macrophages. Furthermore, it delivers celecoxib to macrophages and reduces PGE2 production from these cells. In vivo studies in a murine paw inflammation model showed nanoemulsion presence at the inflamed site, specifically in COX-2 expressing macrophages compared to neutrophils. Supporting our hypothesis, celecoxib delivered through a nanoemulsion demonstrated time-dependent reduction in fluorescence from the inflamed paw, indicative of reduced macrophage infiltration. In a neuropathic pain model, celecoxib delivered to macrophages led to reduced pain concomitant with reduced macrophage infiltration at the inflamed site compared to free drug control (cross reference: Kiran Vasudeva, Dissertation, 2015). In conclusion, inhibition of COX-2 in macrophages using theranostic nanoemulsions proves to be an effective and generalized strategy facilitating simultaneous therapy and diagnosis, which can be applied to many chronic diseases. The diagnostic information during therapy can be used to tailor the treatment and reduce patient variability leading to personalized medicine. / Mylan School of Pharmacy and the Graduate School of Pharmaceutical Sciences; / Pharmaceutics / PhD; / Dissertation;

ABSTRACT Vascular permeability and angiogenesis are crucial events in the rodent and human uterus in early pregnancy and are regulated by vascular endothelial growth factor (VEGF) and prostaglandins liberated from arachidonic acid by cyclooxygenase 2 (COX2). These events coincide with the typical morphological features of the receptive uterus and are regulated by synchronized release of ovarian hormones (oestrogen and progesterone). However, administration of follicle stimulating hormone (FSH) and human chorionic gonadotropin (hCG), commonly used in assisted reproduction, affect the synchrony of the hormonal milieu, particularly by increasing oestrogen levels. This causes detrimental changes to the uterine morphology and affects vascular permeability at the site of implantation. In the present study, the expression of COX2 and VEGF was compared between control and hyperstimulated rat uteri during the peri-implantation period using immunohistochemistry and Western blot analysis. While in control pregnant rats COX2 and VEGF immunolocalization occurred in the luminal epithelial cells and stroma on consecutive days, strong immunolocalization of COX2 and VEGF occurred in the luminal epithelial cells but was inhibited in the stroma of the hyperstimulated rats. This appears to have resulted in the suppression of stromal decidualization and vascular permeability. Western blot analysis did not show any results. This may be due to low concentrations of the protein in the sample. Since vascular permeability and angiogenesis are critical to the process of implantation and are influenced by VEGF and COX2, disturbance of the pattern of these two proteins by hyperstimulation may contribute to the low implantation rate in IVF programes. immunohistochemistry and Western blot analysis. While in control pregnant rats COX2 and VEGF immunolocalization occurred in the luminal epithelial cells and stroma on consecutive days, strong immunolocalization of COX2 and VEGF occurred in the luminal epithelial cells but was inhibited in the stroma of the hyperstimulated rats. This appears to have resulted in the suppression of stromal decidualization and vascular permeability. Western blot analysis did not show any results. This may be due to low concentrations of the protein in the sample. Since vascular permeability and angiogenesis are critical to the process of implantation and are influenced by VEGF and COX2, disturbance of the pattern of these two proteins by hyperstimulation may contribute to the low implantation rate in IVF programes.

histoplasmose é uma doença granulomatosa crônica, cujo agente etiológico é o fungo dimórfico Histoplasma capsulatum. A infecção ocorre pela inalação de conídios ou pequenos fragmentos de micélio que alcançam os alvéolos, onde se transformam em leveduras que é responsável pela patogenia da doença. A imunidade celular do hospedeiro determina o grau das manifestações clínicas na histoplasmose, sendo a interação entre células T e macrófagos, fundamental para o controle da infecção e erradicação do H. capsulatum. Recentemente, nosso grupo de pesquisa demonstrou a participação de leucotrienos nos mecanismos de defesa do hospedeiro durante a histoplasmose. Neste trabalho descrevemos o papel das prostaglandinas, demonstramos que este mediador lipídico contribui para a patogênese da doença, pois sua inibição, com celecoxibe, resultou na sobrevivência de até 80% dos animais infectados com o inóculo letal de H. capsulatum, em contraste com 100% de mortalidade dos animais somente infectados. Além disso, a inibição das prostaglandinas resultou na diminuição (i) da síntese de citocinas pró-inflamatórias e da resposta imune celular e (ii) do recrutamento de neutrófilos e macrófagos para o espaço bronco-alveolar. Por outro lado, resultou no aumento (iii) de células TCD4+ no pulmão, (iv) na síntese de óxido nítrico por células do parênquima pulmonar, (v) na fagocitose de leveduras de H. capsulatum por macrófagos alveolares e (vi) da síntese de LTB4. Nossos resultados sugerem que prostaglandinas têm papel importante na patogênese na infecção por H. capsulatum, modulando a resposta imune do hospedeiro. / The Histoplasmosis is a chronic granulomatosas disease whose etiologic agent is pathogenic dimorphic fungus Histoplasma capsulatum. Infection occurs mainly by fungal inhalation that reaches the alveoli, where if transforms into leavenings that are responsible for pathogenic diseases. The cellular immunity of the host determines the degree of the clinical manifestations in histoplasmosis, being the interaction between cells T and macrophages, basic for the control of the infection and eradication of the H. capsulatum. Recently, our group of research demonstrated the participation of leukotrienes in the mechanisms of defense of the host during the Histoplasmosis. Beyond this important lipid mediator who participates in the immune reply against H. capsulatum. In this work, we describe another involved mediator, the prostaglandin. In the present work, we demonstrate that the prostaglandins contribute for pathogenic of the disease, being that during its inhibition with celecoxib it resulted in the survival of up to 80% of the infection-mice with inoculum lethal of H. capsulatum, in contrast with 100% of mortality infection-mice. Moreover, the inhibition of prostaglandins resulted in the reduction (i) of the synthesis of pro-inflammatory cytokines and the cellular immune response and (ii) in the migration of neutrophils and macrophages. For other hand, increased (iii) of cells TCD4+ in the lung, (iv) of the nitric oxide synthesis, (v) of phagocytosis of yeast of H. capsulatum for alveolar macrophages and (vi) of the synthesis of LTB4. Our results suggest that prostaglandins have important role in pathogenic in the infection for H. capsulatum, modulating the host immune response.

Made available in DSpace on 2017-07-24T19:22:17Z (GMT). No. of bitstreams: 1 Reila Mendes.pdf: 2640941 bytes, checksum: ae80dd043b80ca7c3792d907a25ab34f (MD5) Previous issue date: 2012-02-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Periodontal disease is an inflammatory chronic disorder caused by a small group of gram-negatives bacteria witch colonizes the subgengival area. This disease is characterized by the destruction of the periodontal tissues, including bone resorption and loss of clinical attachment level. Observational studies have shown an increase in the risk of cardiovascular diseases, specially atherosclerosis and hypertension, among the subjects affected by the periodontal disease. The literature also reports endothelial dysfunction among these patients. Data suggest that the systemic inflammation due to the biofilm present in periodontits and the reduction in the nitric oxide availability may be, at least in part, the cause of endothelial dysfunction, which leads to cardiovascular disorders. An increase in vascular COX-2 expression has been demonstrated among diseases related to endothelial dysfunction. COX-2 expression seems to have an important protector function through the production of arachidonic acid metabolites with vasodilator and antitrombotic properties. Therefore, COX-2 inhibition may represent negative cardiovascular implications. The purpose of this research was to evaluate the effect of COX-2 inhibition on the vascular reactivity and on the heart tissue of animals with periodontitis. At day 0, Wistar rats were subdivided into the following groups: ligature + etoricoxib (the animals received ligatures and were treated with etoricoxib 10 mg/kg p.o., for seven days, from the day 14), ligature + vehicle (the animals were treated with distilled water), sham + etoricoxib (the animals went through a sham procedure: the ligatures were positioned and immediately removed) and sham + vehicle. The rats were prepared for the data collection and sacrificed at day 21. Changes on the vasoconstrictor response were not observed. However, the group ligature + etoricoxib showed a tendency to have the vasodilator response reduced. All the groups showed histological cardiac alterations, especially the groups that received etoricoxib, when submitted to ischemia with isoprenaline. It is suggested, though, that COX-2 inhibition in an experimental model of periodontal disease may increase cardiovascular disorders. / A periodontite é uma doença inflamatória crônica iniciada e perpetuada por bactérias anaeróbicas gram-negativas que colonizam a área subgengival. Esta doença é caracterizada pela destruição do tecido periodontal de inserção, reabsorção óssea, infiltração de leucócitos e formação de bolsa periodontal. Estudos observacionais têm mostrado um significativo aumento do risco de doenças cardiovasculares, principalmente aterosclerose e hipertensão, entre pessoas com periodontite. A literatura mostra também a presença de disfunção endotelial nesses pacientes. Os dados sugerem que a inflamação sistêmica induzida pela microbiota presente na doença periodontal e a diminuição na biodisponibilidade do óxido nítrico podem ser, pelo menos em parte, a causa da disfunção endotelial, que por sua vez leva a doenças cardiovasculares. Um aumento na expressão vascular da ciclooxigenase-2 (COX-2) tem sido consistentemente demonstrado em patologias que apresentam disfunção endotelial. A expressão da COX-2 nesta condição parece ter um importante papel protetor através da produção de metabólitos do ácido araquidônico com propriedades vasodilatadoras e antitrombóticas. Dessa maneira, a inibição da COX-2 pode apresentar aspectos cardiovasculares negativos. Assim, a proposta deste trabalho foi avaliar o efeito da inibição COX-2 sobre a reatividade vascular e sobre o tecido cardíaco de animais com periodontite. No dia 0, ratos Wistar foram subdivididos nos seguintes grupos: ligadura + etoricoxibe (receberam ligaduras e foram medicados com etoricoxibe 10 mg/kg v.o. por sete dias, a partir do dia 14), ligadura + veículo (receberam água destilada), falso-operado + etoricoxibe (passaram pelo procedimento de falsa-cirurgia, as ligaduras foram colocadas e imediatamente removidas) e falso-operado + veículo. Os animais foram preparados para aferição dos dados e sacrificados no dia 21. Não foram observadas alterações na resposta vasoconstritora, porém o grupo ligadura + etoricoxibe mostrou uma tendência em ter a resposta vasodilatadora reduzida. Quando submetidos à isquemia com isoprenalina, todos os grupos apresentaram alterações histológicas cardíacas, especialmente os que receberam etoricoxibe. Sugere-se, pois, que a inibição da COX-2 em um modelo experimental de periodontite exacerbe alterações cardiovasculares.

Celecoxib is a COX-2 selective non-steroidal anti-inflammatory drug which has been shown to inhibit growth and induce apoptosis in various cancer cell lines. Using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and an apoptosis detection kit, we demonstrated that celecoxib was able to induce growth inhibition and apoptosis in a dose-dependent manner in 3 NPC cell lines: HK-1, Hone-1, and C666-1. Afterwards, a proteomic approach was used to study the underlying mechanisms involved in celecoxib-mediated effects on two COX-2 positive NPC cell lines (HK-1 and C666-1). Results showed that a total of 18 protein spots were differentially expressed in the HK-1 and C666-1 cells. On the other hand, we also compared the proteomic expression profile between an NPC cell line (C666-1) and a normal nasopharynx cell line (NP69) in order to study whether those differentially expressed proteins after celecoxib treatment were also involved in NPC carcinogenesis. Proteomics results with confirmation using Western blotting discovered that HSP27 phosphorylated of serine 82 (HSP27-pSer82) protein was up-regulated in C666-1 cells when compared with that in NP69 cells. After treatment with celecoxib, expression of HSP27-pSer82 protein was down-regulated in both HK-1 and C666-1 cells. These findings suggest that down-regulation of HSP27-pSer82 protein expression may have mediated the growth-inhibitory effects of celecoxib in HK-1 and C666-1 cells. Finally, other differential expressed proteins identified from proteomics with confirmation by immunocytochemical staining in the 2 NPC cell lines and 40 NPC patient specimens showed that down-regulation of annexin 2 and beta2-tubulin may be important in NPC formation. / COX-2 over-expression has been found in various cancers such as colorectal cancer, liver cancer and lung cancer. In vivo studies have shown that mice overexpressing COX-2 developed breast cancer whereas COX-2 knockout mice had reduced rates of cancer formation in the intestines and skin. In the present study, COX-2 expression in NPC patient biopsies was examined and correlated with the clinicopathological data of the patients. Immunocytochemical staining showed that COX-2 protein was over-expressed in 84.6% (66/78) of non-metastatic NPC patients and was associated with an advanced nodal stage (P<0.05). All these data support an important role for COX-2 in NPC pathogenesis. / In summary, this study is the first to identify HSP27-pSer82 protein as a potential target of celecoxib in NPC cells. Detailed investigations of the functional role of molecular targets identified in this study would improve our understanding of the chemotherapeutic effects of celecoxib and, in the long run, may lead to a more effective chemotherapeutic treatment to this common cancer. / Nasopharyngeal carcinoma (NPC) is prevalent in southern China. Although early stage patients have a high rate of cure with radiotherapy alone, the prognosis for those with stage III or IV disease remains poor due to subsequent development of distant metastases. Therefore there is an urgent need to develop novel biologic agents to improve treatment outcomes. / Chan, Ming Lok. / Adviser: Anthony T.C. Chan. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3418. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 141-171). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

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<p>After drinking water, the fluid quickly leaves the stomach thereby creating a hypotonic luminal environment in the duodenum. This in turn constitutes a potential threat to the integrity of the duodenal epithelium. It therefore seems highly likely that luminal hypotonicity activates physiological mechanisms that aim to increase luminal osmolality. One such physiological mechanism may be to increase mucosal permeability thereby facilitating the transport of osmolytes into the lumen.</p><p>A draw-back of performing experiments in anesthetized animals is that surgery <i>per se</i> depresses gut functions, such as peristalsis, by mechanisms involving endogenous prostaglandins. In this thesis it is shown that inhibition of cyclooxygenase-2 (COX-2), in animals subjected to an abdominal operation, restore and/or improve duodenal functions such as motility, mucosal bicarbonate secretion, hypotonicity-induced increase in mucosal permeability and the osmolality-adjusting capability.</p><p>Experiments revealed that the stomach is resistant to hypotonic challenge while the jejunum is more sensitive to hypotonicity-induced increase in mucosal permeability than the duodenum. The hypotonicity-induced increase in duodenal mucosal permeability is not due to injury but possibly reflects physiological dilatation of paracellular shunts.</p><p>Luminal perfusion of the duodenum with an isotonic solution lacking Cl^- decreased bicarbonate secretion while the lack of luminal Na⁺ increased mucosal permeability. Stimulation of bicarbonate secretion by COX-2 inhibition is to a large extent dependent on luminal Cl^- while that induced by vasoactive intestinal peptide is not.</p><p>The hypotonicity-induced increase in mucosal permeability involves the release and action of serotonin (5-HT) on 5-HT₃ and 5-HT₄ receptors and stimulation of enteric nerves strongly implicating physiological regulation of this process.</p>

After drinking water, the fluid quickly leaves the stomach thereby creating a hypotonic luminal environment in the duodenum. This in turn constitutes a potential threat to the integrity of the duodenal epithelium. It therefore seems highly likely that luminal hypotonicity activates physiological mechanisms that aim to increase luminal osmolality. One such physiological mechanism may be to increase mucosal permeability thereby facilitating the transport of osmolytes into the lumen. A draw-back of performing experiments in anesthetized animals is that surgery per se depresses gut functions, such as peristalsis, by mechanisms involving endogenous prostaglandins. In this thesis it is shown that inhibition of cyclooxygenase-2 (COX-2), in animals subjected to an abdominal operation, restore and/or improve duodenal functions such as motility, mucosal bicarbonate secretion, hypotonicity-induced increase in mucosal permeability and the osmolality-adjusting capability. Experiments revealed that the stomach is resistant to hypotonic challenge while the jejunum is more sensitive to hypotonicity-induced increase in mucosal permeability than the duodenum. The hypotonicity-induced increase in duodenal mucosal permeability is not due to injury but possibly reflects physiological dilatation of paracellular shunts. Luminal perfusion of the duodenum with an isotonic solution lacking Cl- decreased bicarbonate secretion while the lack of luminal Na+ increased mucosal permeability. Stimulation of bicarbonate secretion by COX-2 inhibition is to a large extent dependent on luminal Cl- while that induced by vasoactive intestinal peptide is not. The hypotonicity-induced increase in mucosal permeability involves the release and action of serotonin (5-HT) on 5-HT3 and 5-HT4 receptors and stimulation of enteric nerves strongly implicating physiological regulation of this process.

In clinical situations, most of the patients suffer from inflammation and acute postoperative pain after surgery. Postoperative pain has been emphasized as a very crucial issue in improving the quality of medical care in each medical center. Therefore, management of the postoperative pain is an effective approach to reduce the painful unpleasant feeling, complications, and death rate after surgery. Surgical trauma results in the induction of COX-2, leading to the release of prostaglandins, which sensitize peripheral nociceptors and increase the excitability of spinal neurons, producing pain hypersensitivity in the surrounding uninjured tissue.The purpose of this study is to test the preventive effect of COX-2 inhibitor SC-236 for post-operative pain by rat plantar incision model.Then, we explored whether SC-236 is more effective in reducing the hyperalgesia and inflammation response administered before incision than after incision. Furthermore, we used male Sprague-Dawley rats received plantar incision were used in this study, the rats received subcutaneous injection of SC-236 before or after plantar incision. Behavior teste of mechanical allodynia¡Bthermal hyperalgesia and COX-2 expression level was determined at 4 h and 1, 2, and 3 days after surgery. Mechanical allodynia was measured by mechanical withdrawal threshold that was determined by stimulating with von Frey filaments stimulation. Thermal hyperalgesia was measured by thermal withdrawal thermal tested by radioactive thermal assay. Mechanical allodynia¡Bthermal hyperalgesia and COX-2 expression level were measured at various time points by behavior teste¡Breal-time polymerase chain reaction¡Bwestern blot and immunohistochemistry. The data from pre-incisional injection of SC-236 was compared with that from post-incisional injection of SC-236.The results revealed pre-incisional injection of COX-2 inhibitor significantly inhibited thermal hyperalgesia but not mechanical allodynia then post-incisional injection of COX-2 inhibitor group. Skin of pre-incisional injection of SC-236 show significant decreased mRNA expression of COX-2 at 1 day and 2 day after incision evidenced by real-time polymerase chain reaction. Western blot and immunohistochemistry also show significant decreased protein expression of COX-2 at 4 hours and 1 day after incision. Therefore, pre-incisional administration of SC-236 could prevent the surgical wound induced thermal hyperalgesia and decrease mRNA and protein expression level of cutaneous COX-2 at 4 hours and one day after surgical incision compared to post-incisional administration of SC-236 .

Colorectal cancer, among other tumors, is characterized by elevated levels of prostaglandins due to the up-regulation of cyclooxygenase -2 (COX-2), a key enzyme in the eicosanoid biosynthesis pathway. Prostaglandin E2 (PGE2) is an important prostaglandin that exerts its biological function via four transmembrane G protein coupled receptors (EP1-4), among which the EP4 receptor is the most important. The relevance of EP4 receptor to the carcinogenic process and the consequences of its interaction with PGE2 were explored in this dissertation.Despite the importance of the EP4 receptor in colon carcinogenesis, studies looking at the receptor expression during cancer progression have not been extensive. One study showed that the protein levels of EP4 receptor were elevated in colon cancer whereas another study indicated that mRNA levels were decreased in tumor compared to normal. We expanded these observations and now report that the elevated protein levels of EP4 receptor in cancer are due to increased translation of proteins.In addition, we identified S100P as a novel downstream target of the PGE2/EP4 receptor signaling pathway. S100P has been previously implicated in a number of gastro-intestinal cancers such as pancreatic, gastric and colon cancers. However, its regulation via the PGE2/EP4 receptor signaling pathway has never been investigated. Here, we show that PGE2 via the EP4 receptor signaling leads to the transcriptional activation of S100P and that this activation happens exclusively in the presence of CREB. In summary, this dissertation brings to light novel therapeutic targets which could be used as potential markers to stratify colon cancer patients as well as avenues for clinical intervention for the management of colon carcinogenesis.