Inhibition of soluble epoxide hydrolase (SEH), the enzyme responsible for degradation of vasoactive epoxides, protects against cerebral ischemia in rats. However, the molecular and biological mechanisms that confer protection in normotension and hypertension remain unclear. Here we show that 6 weeks of SEH inhibition via 2 mg/day of 12-(3-adamantan-1-ylureido) dodecanoic acid (AUDA) in spontaneously hypertensive stroke-prone (SHRSP) rats protects against cerebral ischemia induced by middle cerebral artery occlusion, reducing percent hemispheric infarct and neurodeficit score without decreasing blood pressure. This level of cerebral protection was similar to that of the angiotensin-converting enzyme inhibitor, enalapril, which significantly lowered blood pressure. SEH inhibition is also protective in normotensive WistarKyoto (WKY) rats, reducing both hemispheric infarct and neurodeficit score. In SHRSP rats, SEH inhibition reduced wall-to-lumen ratio and collagen deposition and increased cerebral microvessel density, although AUDA did not alter middle cerebral artery structure or microvessel density in WKY rats. An apoptosis mRNA expression microarray of brain tissues from AUDAtreated rats revealed that AUDA modulates gene expression of mediators involved in the regulation of apoptosis in neural tissues of both WKY and SHRSP rats. Hence, we conclude that chronic SEH inhibition protects against cerebral ischemia via vascular protection in SHRSP rats and neural protection in both the SHRSP and WKY rats, indicating that SEH inhibition has broad pharmacological potential for treating ischemic stroke. Epoxyeicosatrienoic acids (EETs), lipid metabolites produced from arachidonic acid by CYP450 enzymes, are novel mediators that antagonize the sequela of hypertension, 1 match cerebral blood flow to increased neural activity and metabolic demand, promotes angiogenesis, 2 and protect against ischemia.3,4 Because ischemic stroke occurs with loss of cerebral blood flow and is strongly associated with hypertension, modulation of epoxide degradation has potential in managing ischemic stroke. Unfortunately, pharmacological utility of exogenous EETs is impractical because the epoxides are rapidly degraded by the soluble epoxide hydrolase (SEH) into their less active diol, dihydroxyeicosatrienoic acids. 5In fact, human SEH polymorphisms are linked to the incidence of ischemic stroke, 6 and this association could be related to modifications in SEH activity, and thus epoxide catabolism. 7 An alternative strategy that has been used to increase EETs systemically is SEH inhibition. 1 We previously showed that the SEH inhibitor 12-(3-adamantan-1-yl-ureido) dodecanoic acid (AUDA) protects against cerebral ischemia in spontaneously hypertensive stroke-prone (SHRSP) rats, an animal model of essential hypertension.8 Interestingly, chronic AUDA treatment in SHRSP rats effectively decreased infarct size induced by middle cerebral artery occlusion (MCAO)
Natural products are important sources of anti-cancer lead molecules. Many successful anti-cancer drugs are natural products or their analogues. Many more are under clinical trials. The present review focuses on chemopreventive and anti-cancer activities of polar and non-polar extracts, semi purified fractions and pure molecules from terrestrial plants of India reported between 2005 and 2010 emphasizing possible mechanisms of action of pure molecules.
Abstract-Obesity and hypertension have been identified as cardiovascular risk factors that contribute to the progression of end-stage renal disease. To examine the mechanisms by which a high-fat diet and hypertension contribute to endothelial dysfunction and renal injury, 8-week-old male spontaneously hypertensive rats and Wistar rats were fed a high-fat (36% fat) or a normal-fat (7% fat) diet for 10 weeks. The high-fat diet increased body weight in Wistar and hypertensive rats by 25 and 31 g, respectively. Systolic blood pressure was higher in the hypertensive rats compared with Wistar rats; however, blood pressure was unaltered by the high-fat diet. Afferent arteriole response to acetylcholine was impaired in the high-fat groups after just 3 weeks. Renal macrophage infiltration was increased in the hypertensive high-fat group compared with others, and monocyte chemoattractant protein-1 excretion was increased in both of the high-fat-fed groups. Renal PCR arrays displayed significant increases in 2 inflammatory genes in hypertensive rats fed a normal diet, 1 gene was increased in high-fat-fed Wistar rats, whereas 12 genes were increased in high-fat-fed hypertensive rats. Urinary albumin excretion was increased in the hypertensive rats compared with the Wistar rats, which was further exacerbated by the high-fat diet. Glomerular nephrin expression was reduced and desmin was increased by the high-fat diet in the hypertensive rats. Our results indicate that endothelial dysfunction precedes renal injury in normotensive and spontaneously hypertensive rats fed a high-fat diet, and hypertension with obesity induces a powerful inflammatory response and disruption of the renal filtration barrier. Key Words: obesity Ⅲ inflammation Ⅲ hypertension Ⅲ renal disease O besity and hypertension are comorbid pathological conditions that have been identified as independent risk factors for the development of endothelial dysfunction and renal disease. 1 These risk factors are increasing in prevalence at an alarming rate, with Ͼ30% of the US population classified as obese, and 1 in 3 adult Americans currently suffering from hypertension. Blood pressure is strongly correlated with body mass index, and in the Framingham Offspring Study, Յ78% of male hypertensive cases were attributable to obesity. 2 Independently obesity increases the risk for chronic kidney disease 4-fold, 3 hypertensive patients account for 25% of all chronic kidney disease patients, and obese patients with hypertension are at the greatest risk for developing chronic renal disease. 4 -6 Independently, hypertension and obesity have been linked with the development of insulin resistance, endothelial dysfunction, inflammation, and renal injury. 7,8 However, these conditions are commonly found in combination, and it is now becoming apparent that the ensuing renal injury and vascular dysfunction are results of the combination of the 2 risk factors. 9 Animal models of obesity and hypertension, such as the obese Zucker rat, have been shown to develop albuminuria, progress...
Introduction/Objectives: Screening guidelines for breast, cervical, and colorectal cancer (CRC) are less clear for older adults due to the potential harms that may result from screening. Understanding older adults’ attitudes and perceptions, especially racial/ethnic minority and underserved adults, of cancer screening can help health care providers determine how best to communicate with older adults about cancer screening and screening cessation. The objective of this study was to determine how older adults primarily from minority/underserved backgrounds perceive cancer screening and overscreening. Methods: Four focus groups (n = 39) were conducted with adults (>=65 years of age) in 3 community settings in south-central Pennsylvania. Two focus groups were conducted in Spanish and translated to English upon transcription. Focus group data was managed and analyzed using QSR NVivo 12. Inductive thematic analysis was used to analyze the data where themes emerged following the coding process. Results: The focus group participants had an average age of 74 years and were primarily female (74%) and Hispanic (69%), with 69% reporting having less than a high school degree. Four key themes were identified from the focus groups: (1) importance of tailored and targeted education/information; (2) impact of physician/patient communication; (3) impact of barriers and facilitators to screening on cancer screening cessation; and (4) awareness of importance of screening. Participants were more likely to be agreeable to screening cessation if they received specific information regarding their health status and previous medical history from their physician as to why screening should be stopped and told by their physician that the screening decision is up to them. Conclusions: Older adults prefer individualized information from their physician in order to justify screening cessation but are against incorporating life expectancy into the discussion. Future research should focus on developing interventions to test the effectiveness of culturally tailored screening cessation messages for older adults.
Knight SF, Yuan J, Roy S, Imig JD. Simvastatin and tempol protect against endothelial dysfunction and renal injury in a model of obesity and hypertension. Am J Physiol Renal Physiol 298: F86 -F94, 2010. First published November 11, 2009 doi:10.1152/ajprenal.00351.2009.-Obesity and hypertension are risk factors for the development of chronic kidney disease. The mechanisms by which elevated blood pressure and fatty acids lead to the development of renal injury are incompletely understood. Here, we investigated the contributions of cholesterol and oxidative stress to renal endothelial dysfunction and glomerular injury in a model of obesity and hypertension. Male Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR) were fed a normal diet, a high-fat diet, a high-fat diet with tempol, or a high-fat diet with simvastatin for up to 10 wk. Blood pressure was not altered by a high-fat diet or treatments. After 3 wk, renal afferent dilatory responses to acetylcholine were impaired in WKY rats and SHR fed a high-fat diet. Tempol treatment prevented this vascular dysfunction in both strains; however, simvastatin treatment demonstrated greater beneficial effects in the SHR. Albuminuria was observed in the SHR and was exacerbated by a high-fat diet. Tempol and simvastatin treatment significantly ameliorated albuminuria in the SHR fed a high-fat diet. Ten weeks on a high-fat resulted in an increase in urinary 8-isoprostane in WKY rats and SHR, and tempol and simvastatin treatment prevented this increase, indicating a reduction in renal oxidative stress. Monocyte chemoattractant protein-1 (MCP-1) excretion was significantly elevated by a high-fat diet in both strains, and tempol prevented this increase. Interestingly, simvastatin treatment had no effect on MCP-1 levels. These data indicate that tempol and simvastatin treatment via a reduction in oxidative stress improve renal endothelial function and decrease glomerular injury in a model of obesity and hypertension. kidney; oxidative stress; metabolic syndrome; inflammation OBESITY HAS REACHED EPIDEMIC proportions in the developed world, with 50% of the US population now classified as overweight or obese, and the numbers are rising (National Health and Nutrition Examination Survey, available at http:// www.cdc.gov/nchs/nhanes.htm). Obesity is associated with increased risk of developing diabetes, hypercholesterolemia, and hypertension, which together are described as the metabolic syndrome (18, 29). Independently, obesity and hypertension increase the risk of renal dysfunction; obese patients are four times more likely to develop renal disease than nonobese patients, and hypertension accounts for 25% of renal dysfunction cases (27). Obese patients are at a higher risk of developing hypertension, therefore combining risk factors and compounding the negative effect on cardiovascular health. In particular, renal injury associated with obesity and hypertension has been shown to be more severe than renal disease observed as a result of each risk factor alone. This addi...
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