ABSTRACT. Purpose. NSAIDs constitute an important class of drugs with therapeutic applications that have spanned several centuries. Treatment of inflammatory conditions such as rheumatoid arthritis (RA) and osteoarthritis (OA) starting from the classic drug aspirin to the recent rise and fall of selective COX-2 inhibitors has provided an enthralling evolution. Efforts to discover an ultimate magic bullet to treat inflammation continues to be an important drug design challenge. This review traces the origins of NSAIDs, their mechanism of action at the molecular level such as cyclooxygenase (COX) inhibition, development of selective COX-2 inhibitors, their adverse cardiovascular effects, and some recent developments targeted to the design of effective anti-inflammatory agents with reduced side effects. Methods. Literature data is presented describing important discoveries pertaining to the sequential development of classical NSAIDs and then selective COX-2 inhibitors, their mechanism of action, the structural basis for COX inhibition, and recent discoveries. Results. A brief history of the development of NSAIDs and the market withdrawal of selective COX-2 inhibitors is explained, followed by the description of prostaglandin biosynthesis, COX isoforms, structure and function. The structural basis for COX-1 and COX-2 inhibition is described along with methods used to evaluate COX-1/COX-2 inhibition. This is followed by a section that encompasses the major chemical classes of selective COX-2 inhibitors. The final section describes briefly some of the recent advances toward developing effective anti-inflammatory agents such as nitric oxide donor NO-NSAIDs, dual COX/LOX inhibitors and anti-TNF therapy. Conclusions. A great deal of progress has been made toward developing novel anti-inflammatory agents. In spite of the tremendous advances in the last decade, the design and development of a safe, effective and economical therapy for treating inflammatory conditions still presents a major challenge.

Hypertension is a highly prevalent cardiovascular risk factor in the world and particularly overwhelming in low and middle-income countries. Recent reports from the WHO and the World Bank highlight the importance of chronic diseases such as hypertension as an obstacle to the achievement of good health status. It must be added that for most low and middle-income countries, deficient strategies of primary healthcare are the major obstacles for blood pressure control. Furthermore, the epidemiology of hypertension and related diseases, healthcare resources and priorities, the socioeconomic status of the population vary considerably in different countries and in different regions of individual countries. Considering the low rates of blood pressure control achieved in Latin America and the benefits that can be expected from an improved control, it was decided to invite specialists from different Latin American countries to analyze the regional situation and to provide a consensus document on detection, evaluation and treatment of hypertension that may prove to be cost-utility adequate. The recommendations here included are the result of preparatory documents by invited experts and a subsequent very active debate by different discussion panels, held during a 2-day sessions in Asuncion, Paraguay, in May 2008. Finally, in order to improve clinical practice, the publication of the guidelines should be followed by implementation of effective interventions capable of overcoming barriers (cognitive, behavioral and affective) preventing attitude changes in both physicians and patients.

A novel group of hybrid calcium channel (CC) modulators was prepared where the isopropyl ester moiety of isopropyl 1,4-dihydro-2,6-dimethyl-3-nitro-4-(2,1,3-benzoxadiazol-4-yl)pyridine-5-carboxylate (PN 202-791) was replaced by a variety of nitric oxide (*NO) donor nitrooxyalkyl ester substituents. Enantiomers, or diastereomers, having the (R)-configuration at the C-4 position of the 1,4-dihydropyridine ring (1,4-DHP) exhibited more potent in vitro CC antagonist activity on guinea pig ileum longitudinal smooth muscle (GPILSM) than compounds having the (4S)-configuration. None of the nitrooxyalkyl compounds exhibited a contraindicated CC agonist effect on GPILSM that would cause smooth muscle contraction. Structure-activity studies showed the enantiomers having the (S)-configuration at the C-4 position of the 1,4-DHP ring or diastereomers having the a (4S)-configuration at the C-4 position of the 1,4-DHP ring in conjunction with a (1R-)-1-methyl-2-nitrooxyethyl ester substituent exhibited the most potent cardiac CC agonist (positive inotropic) activity on guinea pig left atrium (GPLA). This class of compounds releases *NO in vitro that is enhanced by the presence of a thiol such as N-acetylcysteamine. The novel *NO donor (-)-(S,R)-1-methyl-2-nitrooxyethyl 1,4-dihydro-2,6-dimethyl-3-nitro-4-(2,1,3-benzoxadiazol-4-yl)pyridine-5-carboxylate [(-)-(S,R)-38], which acts as a dual cardioselective calcium channel agonist (GPLA)/smooth muscle selective calciumchannel antagonist (GPILSM), is a useful lead compound for drug discovery targeted to the treatment of congestive heart failure, and it provides a useful research probe to study the structure-function relationship of calcium channels.

Chronic inflammation is an underlying etiological factor in carcinogenesis; nonsteroidal anti-inflammatory drugs (NSAIDs) and their chemically modified NO-releasing prodrugs (NO-NSAIDs) are promising chemopreventive agents. The aim of this study was to conduct a head-to-head comparison between two NO-ASAs possessing different NO donor groups, an organic nitrate [3-nitrooxyphenyl acetylsalicylate (NO-ASA; NCX-4016)] and an N-diazeniumdiolate [NONO-ASA, O 2 -(acetylsalicyloxymethyl)-1-(pyrrolidin-1-yl)diazen-1-ium-1,2-diolate (NONO-ASA; CVM-01)], as antiulcerogenic, analgesic, anti-inflammatory, and antipyretic agents. All drugs were administered orally at equimolar doses. For antiulcerogenic study, 6 h after administration, the number and size of hemorrhagic lesions in stomachs from euthanized animals were counted. Tissue samples were frozen for prostaglandin E 2 (PGE 2 ), superoxide dismutase (SOD), and malondialdehyde determination. For anti-inflammatory study, 1 h after drug administration, the volume of carrageenan-induced rat paw edemas was measured for 6 h. For antipyretic study, 1 h after dosing, fever was induced by intraperitoneal LPS, and body core temperatures measured for 5 h. For analgesic study, time-dependent analgesic effect of prodrugs was evaluated by carrageenan-induced hyperalgesia. Drugs were administered 30 min after carrageenan. NO-ASA and NONO-ASA were equipotent as analgesic and anti-inflammatory agents but were better than aspirin. Despite a drastic reduction of PGE 2 in stomach tissue, both prodrugs were devoid of gastric side effects. Lipid peroxidation induced by aspirin was higher than that observed by prodrugs. SOD activity induced by both prodrugs was similar, but approximately 2-fold higher than that induced by aspirin. CVM-01 is as effective as NCX-4016 in anti-inflammatory, analgesic, and antipyretic assays in vivo, and it showed an equivalent safety profile in the stomach. These results underscore the use of N-diazeniumdiolate moieties in drug design.

A novel group of O 2 -acetoxymethyl-protected diazeniumdiolate-based non-steroidal antiinflammatory prodrugs (NONO-NSAIDs) were synthesized by esterifying the carboxylate group of aspirin, ibuprofen, or indomethacin with O 2 -acetoxymethyl 1-[N-(2-hydroxyethyl)-Nmethylamino]diazeniumdiolate. The resulting nitric oxide (•NO)-releasing prodrugs (7-9) did not exhibit in vitro cyclooxygenase (COX) inhibitory activity against the COX-1 and COX-2 isozymes (IC 50 s > 100 μM). In contrast, prodrugs 7 and 8 significantly decreased carrageenaninduced rat paw edema showing enhanced in vivo anti-inflammatory activities (ID 50 's = 552 and 174 μmol/kg, respectively) relative to those of the parent NSAIDs aspirin (ID 50 = 714 μmol/kg), and ibuprofen (ID 50 = 326 μmol/kg).. The rate of porcine liver esterase-mediated •NO release from prodrugs 7-9 (2 moles of •NO/mol of test compound in 0.6-6.5 min) was substantially higher compared to that observed without enzymatic catalysis (about 1 mol of •NO/mol of test compound in 40-48 h). These incubation studies suggest that both •NO and the parent NSAID would be released upon in vivo activation (hydrolysis) by esterases. Data acquired in an in vivo ulcer index (UI) assay showed that NONO-aspirin (UI = 0.8), NONO-indomethacin (UI = 1.3), and particularly NONO-ibuprofen (UI = 0), were significantly less ulcerogenic compared to the parent drugs aspirin (UI = 57), ibuprofen (UI = 46) or indomethacin (UI = 34) at equimolar doses. The release of aspirin and •NO from the NONO-aspirin (7) prodrug constitutes a potentially beneficial property for the prophylactic prevention of thrombus formation and adverse cardiovascular events such as stroke and myocardial infarction.

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The carboxylic acid group of the anti-inflammatory (AI) drugs aspirin and indomethacin was covalently linked to the 1-(2-carboxypyrrolidin-1-yl)diazen-1-ium-1,2-diolate ion via a one-carbon methylene spacer to obtain two new hybrid prodrugs. The aspirin prodrug ( 23) was a 2.2-fold more potent AI agent than aspirin, whereas the indomethacin prodrug ( 26) was about 1.6-fold less potent than indomethacin. Prodrugs 23 and 26 slowly released nitric oxide (NO) upon dissolution in phosphate buffer at pH 7.4 (1.1 mol of NO/mol of compound after 43 h), but the rate and the extent of NO release were higher (1.9 mol of NO/mol of compound in 3 min or less) when the compounds were incubated in the presence of porcine liver esterase. In vivo ulcer index (UI) studies showed that the aspirin prodrug 23 (UI = 0.7) and indomethacin prodrug 26 (UI = 0) were substantially less ulcerogenic than the parent drugs aspirin (UI = 51) and indomethacin (UI = 64).