Lenalidomide modulates high fat diet induced inflammation in human vascular smooth muscle cells

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Description
Vascular inflammation plays a key role in the development and progression of cardiovascular disease. High fat diet has been associated with cardiovascular risk (1). Therefore, as poor nutrition and poor diet become more widespread, the number of people at risk

Vascular inflammation plays a key role in the development and progression of cardiovascular disease. High fat diet has been associated with cardiovascular risk (1). Therefore, as poor nutrition and poor diet become more widespread, the number of people at risk to cardiovascular disease increases. We hypothesized that using the cancer drug lenalidomide would reverse the inflammation caused by high fat conditions. Human aortic vascular smooth muscle cells were used as an in vitro model to analyze the effect of lenalidomide on high fat diet induced inflammation. Palmitate, a saturated fatty acid was used to induce inflammation. Since lenalidomide has been shown to inhibit cytokine production and attenuate oxidative stress, we investigated whether lenalidomide alters select markers of vascular inflammation in vascular smooth muscle treated with high fat exposure using palmitate. These markers were cyclooxygenase-2 (COX-2) protein levels, TNF-α pro-inflammatory cytokine levels, and superoxide ions. Lenalidomide (5 µM) reversed COX-2 protein expression in cells exposed to high fat conditions (100 µM palmitate). In conclusion, high fat exposure elicits an inflammatory response in cultured primary human vascular smooth muscle, but this response appears to be independent of local cytokine or ROS production. Lenalidomide, although effective at reversing palmitate-induced COX-2, alone augments the pro-inflammatory mediators, COX-2 and TNF-α as well as promotes oxidative stress independent of high fat exposure in human vascular smooth muscle cells.
Date Created
2017-12
Agent

Evaluation of inflammatory responses and tissue triglyceride concentrations following high fat intake in developing rodents

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Description
High fat diets (HFD) are known to cause hepatic non-alcoholic steatosis in rats in as few as four weeks. Accumulation of triglycerides in liver and skeletal muscle is associated with insulin resistance and obesity. However, studies of fat accumulation in

High fat diets (HFD) are known to cause hepatic non-alcoholic steatosis in rats in as few as four weeks. Accumulation of triglycerides in liver and skeletal muscle is associated with insulin resistance and obesity. However, studies of fat accumulation in cardiac muscle are not as prevalent. Therefore, the first hypothesis of this study was that HFD would lead to hepatic steatosis as well as lipid accumulation in pectoralis and cardiac muscles, tissues responsible for the majority of postprandial glucose disposal. Prior studies also indicated that HFD leads to increased inflammation and oxidative stress within the vasculature resulting in impaired endothelium-dependent vasodilation, however biomarkers of immune system reactivity were not assessed. Therefore, the second aim of this study was to explore additional pathways of immune system reactivity and stress (natural antibodies; heat shock protein 60 (HSP60)) in rats fed either a control (chow) or high fat (HFD) diet. HSP60 has also recently been recognized as an early marker of vascular dysfunction in humans. The hypothesis was that immune system reactivity and early vascular dysfunction would be heightened in rats fed a HFD compared to chow-fed controls. Young male Sprague-Dawley rats (140-160g) were maintained on a chow diet (5% fat, 57.33% carbohydrate, 3.4kcal/g) or HFD (60% fat, 20% carbohydrate, 5.24 kcal/g) for 6 weeks. HFD rats developed hepatic steatosis with significantly elevated liver triglyceride concentrations compared to chow-fed controls (20.73±2.09 vs.9.75±0.52 mg triglycerides/g tissue, respectively; p=0.001). While lipid accumulation appeared to be evident in the pectoralis muscle from HFD rats, triglyceride concentrations were not significantly different from controls. Likewise, there was no evidence of lipid infiltration in cardiac muscles of HFD rats. Lipid accumulation in the liver of overweight HFD rats may contribute to the observed insulin resistance in these animals. Contrary to the second hypothesis, there were no significant differences in plasma HSP60 expression between HFD and chow rats (p>0.05). Likewise, hemagglutination and hemolysis responses were similar between HFD and chow-fed rats (p>0.05). These findings suggest that immune system responses may not be affected by 6 weeks of high fat intake and that HSP60 is not an early marker of vascular dysfunction in this rodent model.
Date Created
2013-05
Agent

Genistein-mediated diet tends to increase oxidative stress in the vasculature of female ob/ob mice

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Description
Morbid obesity is associated with cardiovascular and metabolic disorders. A major contributor to the pathogenesis of these diseases is impaired vasodilation resulting from elevated reactive oxygen species (ROS). This is because certain ROS such as superoxide are raised with obesity

Morbid obesity is associated with cardiovascular and metabolic disorders. A major contributor to the pathogenesis of these diseases is impaired vasodilation resulting from elevated reactive oxygen species (ROS). This is because certain ROS such as superoxide are raised with obesity and scavenge the endogenous vasorelaxant nitric oxide, resulting in hypertension. The objective of this study was to measure the ability of genistein to quench superoxide in the vasculature of ob/ob mice, an animal model of obesity and type 2 diabetes. Genistein is an isoflavonic phytoestrogen naturally found in soy products. While genistein has documented antioxidant and anti-inflammatory properties, it is not known whether this protects the vasculature from oxidative stress. Genistein was hypothesized to reduce superoxide in arteries from female ob/ob mice. The superoxide indicator dihydroethidium (DHE) [2µL/mL HEPES buffer] was added to isolated aortae and mesenteric arteries from mice fed either a control (standard rodent chow containing 200-300 mg genistein/kg) or genistein-enriched (600mg genistein/kg rodent chow) diets for 4 weeks. Frozen tissues sections were collected onto glass microscope slides and examined using confocal microscopy. Contrary to the hypothesis, a diet containing twice the amount of genistein found in standard chow did not significantly reduce superoxide concentrations in aortae (p=0.287) or mesenteric arteries (p=0.352). Superoxide dismutase, an antioxidant enzyme that breaks down superoxide, was significantly upregulated in the genistein-enriched diet group (p=0.004), although this elevation did not promote the breakdown of superoxide. In addition, the inflammatory marker iNOS was not downregulated in the genistein-enriched diet group (p>0.05). The results indicate that high amounts of isoflavones, like genistein, may not exhibit the purported antioxidant effects in the vasculature of obese or diabetic subjects. Further studies examining arteries from ob/ob mice fed a genistein-free diet are needed to elucidate the true effects of genistein on oxidative stress.
Date Created
2014-05
Agent

Effects of novel functional food on wellness indicators

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Description
With obesity and metabolic diseases reaching epidemic levels, it is important to find ways to increase physical activity and improve diet. Previous studies have shown that improvements in mood can increase desire to perform physical activity, and that vitamin C

With obesity and metabolic diseases reaching epidemic levels, it is important to find ways to increase physical activity and improve diet. Previous studies have shown that improvements in mood can increase desire to perform physical activity, and that vitamin C intake is linked to improvements in mood. Based on this, two hypotheses were formed and tested to investigate the effect on physical activity levels and mood states from vitamin C supplementation at a dose of one gram per day in the form of a novel functional food. Thirty-one college students or faculty at Arizona State University were screened from a pool of applicants and placed into either a vitamin C or placebo group; all participants received the novel functional food to eat daily for four weeks. Serum levels of vitamin C, weight, height, BMI, body fat percentage, mood, and physical activity were measured before and after the functional food intervention. Vitamin C changed significantly through the course of the study in the experimental group. Baseline data for participants showed a positive correlation between vitamin C status and vigor, and a negative correlation between vitamin C status and weight and BMI. Physical activity was not related to vitamin C status, according to baseline data, and it did not significantly change over the course of the study. The results indicate that variance in BMI can be attributed to vitamin C status, but the study should be refined and tested again.
Date Created
2014-05
Agent

Differential Activation of Unfolded Protein Response in Two Osteosarcoma Cell Lines Following Hypoxic and Chemotherapeutic Stress

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Description
Osteosarcoma (OS) is the most prevalent primary tumor of bone in the pediatric age group [1]. The long-term cancer free survival has improved in patients with localized cancer; however, less than 20% of patients diagnosed with metastatic disease survive without

Osteosarcoma (OS) is the most prevalent primary tumor of bone in the pediatric age group [1]. The long-term cancer free survival has improved in patients with localized cancer; however, less than 20% of patients diagnosed with metastatic disease survive without relapse [2]. While these findings emphasize the urgent need for new therapeutic agents, the lack of understanding of the factors and the tumor microenvironment that lead to therapy resistance in OS has significantly hampered progress towards improved prognosis. Recent clinical reports have shown a negative correlation between tumor hypoxia and overall survival in OS patients [4]. In addition to the up-regulation of hypoxia inducible factors (HIFs), it has been shown that hypoxia can trigger an adaptive response such as the unfolded protein response (UPR) that allows tumor cells to avoid therapy-induced death [3,4,7,10].
Using in vitro experimental models of both SAOS-2 (non-metastatic) and 143-b (metastatic) osteosarcoma cell lines and Western blot analysis, we have demonstrated that basal levels of molecular chaperone BiP (Binding immunoglobulin protein, or GRP-78) and peIF2α (phospho-eukaryotic initiation factor 2 alpha), both markers of the UPR, were higher in SAOS-2 than 143-b cells. We also show that both these markers were further up-regulated upon exposure to hypoxia, as evidenced by the increase in banding intensity in both SAOS-2 and 143-b cells. Furthermore, analysis of another UPR marker, ATF6 (activating transcription factor 6) showed that basal levels of active nuclear ATF6 were slightly higher in SAOS-2 cells than in 143-b cells. However, unlike the other UPR markers these levels were significantly reduced upon exposure to hypoxia (0.1% O2). In addition to hypoxia, treatment with Cisplatin also had similar effects on the expression of aforementioned UPR markers: BiP and peIF2α. We found that the 143-b OS cells were more sensitive to the Cisplatin treatment than the SAOS-2 OS cells, and thus more prone to cell-mediated death.
Our findings shed light on the unknown mechanisms underlying chemotherapeutic drug resistance in osteosarcoma patients. Our research may lead to novel therapies that seek out and destroy the chemoresistant OS cells within the hypoxia core of tumors, thereby preventing survival and metastasis, and ultimately improving the chances of survival amongst OS patients.
Date Created
2014-05
Agent

Hepatic inflammatory response following high fat diet in adolescent male Sprague-Dawley rats

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Description
There has long been a link tied between obesity and such pathological conditions as nonalcoholic fatty liver disease and type two diabetes. Studies have shown that feeding rats a diet high in fat results in hepatic steatosis and steatohepatitis. Using

There has long been a link tied between obesity and such pathological conditions as nonalcoholic fatty liver disease and type two diabetes. Studies have shown that feeding rats a diet high in fat results in hepatic steatosis and steatohepatitis. Using a novel short term diet of six weeks with male adolescent Sprague-Dawley rats, our laboratory sought to investigate the early effects of high fat intake on the liver. Prior findings in our laboratory found that a high fat diet (HFD) leads to nonalcoholic fatty liver disease as well as other symptoms of metabolic syndrome. This study hypothesized that rats fed a 60% HFD for 6 weeks, unlike a high sucrose or standard chow diet, would have an elevated expression of pro-inflammatory cytokines associated with steatohepatitis. TNF-α, TLR4 and XBP1 were chosen for their link to hepatic inflammation. The results of this study found that contrary to the hypothesis, the high fat diet did not induce significant changes in the expression of any inflammatory marker in comparison to a high sucrose or control chow diet.
Date Created
2015-05
Agent

The Role of Lipolysis in Regulating Plasma Glucose Concentrations in Mourning Doves

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Description
Birds have unusually high plasma glucose concentrations compared to mammals of similar size despite their high metabolic rate. While birds use lipids as their main source of energy, it is still unclear how and why they maintain high plasma glucose

Birds have unusually high plasma glucose concentrations compared to mammals of similar size despite their high metabolic rate. While birds use lipids as their main source of energy, it is still unclear how and why they maintain high plasma glucose concentrations. To investigate a potential underlying mechanism, this study looks at the role of lipolysis in glucose homeostasis. The purpose of this study is to examine the effects of decreased glycerol availability (through inhibition of lipolysis) on plasma glucose concentrations in mourning doves. The hypothesis is that decreased availability of glycerol will result in decreased production of glucose through gluconeogenesis leading to reduced plasma glucose concentrations. In the morning of each experiment, mourning doves were collected at the Arizona State University Tempe campus, and randomized into either a control group (0.9% saline) or experimental group (acipimox, 50mg/kg BM). Blood samples were collected prior to treatment, and at 1, 2, and 3 hours post-treatment. At 3 hours, doves were euthanized, and tissue samples were collected for analysis. Acipimox treatment resulted in significant increases in blood glucose concentrations at 1 and 2 hours post- treatment as well as renal triglyceride concentrations at 3 hours post-treatment. Change in plasma free glycerol between 0h and 3h followed an increasing trend for the acipimox treated animals, and a decreasing trend in the saline treated animals. These results do not support the hypothesis that inhibition of lipolysis should decrease blood glycerol and blood glucose levels. Rather, the effects of acipimox in glucose homeostasis appear to differ significantly between birds and mammals suggesting differing mechanisms for glucose homeostasis.
Date Created
2015-05
Agent

Replacing Dietary Meat with Fish Significantly Increases Plasma Glucose without Affecting Protein Glycation

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Description
Western diets, high in dietary fat and red meat, are associated with hyperglycemia and weight gain, symptoms that promote insulin resistance and diabetes. Previous studies have shown that elevated glucose promotes glycation of circulating proteins such as albumin, which is

Western diets, high in dietary fat and red meat, are associated with hyperglycemia and weight gain, symptoms that promote insulin resistance and diabetes. Previous studies have shown that elevated glucose promotes glycation of circulating proteins such as albumin, which is thought to lead to hyperglycemia complications. It was hypothesized that diets with no meat consumption (pesco-vegetarian and lacto-vegetarian) would reduce protein glycation, in comparison to a diet with meat. Forty six healthy adult omnivorous subjects were randomized into one of three groups and instructed to either consume red meat (i.e. meat) or poultry twice per day (control), eliminate meat and increase fish consumption (pesco-vegetarian), or adopt a vegetarian diet devoid of fish, meat or poultry (lacto-vegetarian) for four weeks. Fasting plasma samples were collected from participants at baseline and after 4 weeks of the dietary intervention. Plasma glucose concentrations were measured using a commercially available kit. Percent glycated albumin was measured on a separate aliquot of plasma by mass spectrometry. Plasma glucose concentrations were significantly increased following 4-weeks of pesco-vegetarian diet (P=0.002, paired t-test). Neither the lacto-vegetarian (P=0.898) or the control diet (P=0.233) affected plasma glucose concentrations. Despite the significant increase in plasma glucose following a pesco-vegetarian diet, no change in percent glycated albumin was observed (P>0.50, ANOVA). These findings may indicate a protective effect of the pesco-vegetarian diet on protein glycation in the presence of elevated plasma glucose and suggest the need for additional studies to examine the link between increased fish consumption and glucose regulation.
Date Created
2015-05
Agent

Comparing Nutritional Physiology and Bioavailable Nutrients between Rural and Urban Populations of Callipepla gambelii

Description
This study is an exploration of the nutritional physiology of Gambel's quail, Callipepla gambelii, in terms of the comparison of rural and urban area populations of this gallinaceous species, and the employment of in situ study by design. The health

This study is an exploration of the nutritional physiology of Gambel's quail, Callipepla gambelii, in terms of the comparison of rural and urban area populations of this gallinaceous species, and the employment of in situ study by design. The health of quail populations is of interest as a resource to recreational enthusiasts, hunters, stakeholders, as well as agencies charged with their management. Quail are the only resident small avian game species known to be native to the southwest that is depended upon by management agencies for recreational opportunities. The condition of the Gambel's quail populations determine regulatory actions with respect to recreational quailing opportunities and these quail represent a species which shows adjustment to human expansion. The combination of morphologic, physical, and plasma nutrient data gathered from samples during this study are hypothesized to show a difference between rural and urban populations of C. gambelii. The hypothesis is that urban quail will display morphological differences, and nutrient differences that are crucial to quail fitness, therefore, potential selective differences. Ground and ambient air temperatures are hypothesized to be higher in urban areas andthus these measurements were taken for site comparison. Plasma nutrient concentrations between rural and urban populations of adult male Gambel's quail were compared for potential existing variations in nutrition. The blood nutrient assays are expected to display increased plasma concentrations of constituents such as glucose, lipids, and proteins, which are known to be involved in growth, reproductive success, and general fitness in the urban quail populations. Morphological data was collected to examine the potential differences in the physical attributes of the sampled quail. A fitness advantage in male Gambel's quail living within urban areas is hypothesized to be associated with differences in plasma nutrients and morphology. The potentially differing plasma nutrients in samples of the C. gambelii in urban versus rural environments is believed to be affected by, and to indicate, differing nutrient availability. Body mass and length, chest circumference as well as skin temperatures were measured to assess potential differences in these outward physical attributes. The urban quail are hypothesized to have reproductive and/or natural selective advantages where their measured morphology may show physical size differences. Differences in the physical attributes of the male Gambel's quail that live in urban areas may be supported through measured morphologic attributes.
Date Created
2015-12
Agent

Changes in Weight Status and the Intestinal Microbiota among College Students

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Description
The transition to college has been identified as a vulnerable period for weight gain and the onset of obesity. Research has shown that the gut microbiota is different in obese compared to lean individuals, but a period of weight gain

The transition to college has been identified as a vulnerable period for weight gain and the onset of obesity. Research has shown that the gut microbiota is different in obese compared to lean individuals, but a period of weight gain has never been studied in free-living individuals. The objective of this longitudinal, observational study was to assess the association between changes in the intestinal microbiota and weight-related outcomes in healthy college students living in on-campus dormitories at Arizona State University (n=39). Anthropometric measures and fecal samples were collected at the beginning and end of the school year, and microbial relative abundance for A. muciniphila, F. prausnitzii, R. gnavus, and L. acidophilus was measured through qPCR analyses. In this population, body mass index (BMI) and waist circumference (WC) increased by 0.97 ± 1.28 kg/m2 and 2.64 ± 4.90 cm, respectively. Wilcoxon-Rank tests revealed that R. gnavus fold change was significantly different between groups of weight loss/maintenance and weight gain ≥ 5% body weight (0.14 [-0.21, 0.64], n=24 vs. -0.14 [-0.92, 0.05], n=15, respectively; p=0.028). Correlation analyses suggested a significant negative association between A. muciniphila fold change and both % WC change and % BMI change (r= -0.66; p<0.01 and r= -0.33; p=0.04, respectively). However, multivariate regression analysis controlling for sex and race/ethnicity showed a significant association between A. muciniphila and % WC change, but not % BMI change (R2= 0.53; p<0.01 and R2= 0.24; p=0.15). F. prausnitzii was not associated with weight-related outcomes in this sample. L. acidophilus was excluded from study analyses after subsequent qPCR trials revealed no amplification in participant samples. Overall, this was the first study to show a relationship between A. muciniphila fold change and weight-related outcomes over a period of weight gain. Specifically, A. muciniphila was strongly negatively associated with WC in this sample. Further research is needed to more accurately describe these associations and potential mechanisms associated with the shift in gut microbiota observed with weight gain. Findings from future research may be used to develop interventions for college students aiming to shift the gut microbiota to prevent weight gain.
Date Created
2017
Agent