Association of Cardiovascular Health Score With Early- and Later-Onset Diabetes and With Subsequent Vascular Complications of Diabetes.

BACKGROUND Little attention has been paid to how well the American Heart Association's cardiovascular health (CVH) score predicts early-onset diabetes in young adults. We investigated the association of CVH score with early- and later-onset diabetes and with subsequent complications of diabetes. METHODS AND RESULTS Our sample included 4547 Black and White adults in the CARDIA (Coronary Artery Risk Development in Young Adults) study without diabetes at baseline (1985-1986; aged 18-30 years) with complete data on the CVH score at baseline, including smoking, body mass index, physical activity, diet quality, total cholesterol, blood pressure, and fasting blood glucose. Incident diabetes was determined based on fasting glucose, 2-hour postload glucose, hemoglobin A1c, or self-reported medication use throughout 8 visits for 30 years. Multinomial logistic regression was used to assess the association between CVH score and diabetes onset at age <40 years (early onset) versus age ≥40 years (later onset). Secondary analyses assessed the association between CVH score and risk of complications (coronary artery calcium, clinical cardiovascular disease, kidney function markers, diabetic retinopathy, and diabetic neuropathy) among a subsample with diabetes. We identified 116 early- and 502 later-onset incident diabetes cases. Each 1-point higher CVH score was associated with lower odds of developing early-onset (odds ratio [OR], 0.64 [95% CI, 0.58-0.71]) and later-onset diabetes (OR, 0.78 [95% CI, 0.74-0.83]). Lower estimates of diabetic complications were observed per 1-point higher CVH score: 19% for coronary artery calcification≥100, 18% for cardiovascular disease, and 14% for diabetic neuropathy. CONCLUSIONS Higher CVH score in young adulthood was associated with lower early- and later-onset diabetes as well as diabetic complications.

Hybridization of amantadine with gardenamide A enhances NMDA antagonism and in vivo anti-PD effects.

Eight hybrids of amantadine (ATD) with a natural modulator gardenamide A (GA) via an alkylene carbonyl bridge or alkylene bridge have been designed and synthesized. Evaluated by electrophysiological assay, compound 5b was confirmed an enhanced NMDAR antagonist compared to ATD with IC50 value of 10.2 ± 1.2 µM. 5b has been demonstrated to reverse the damages of behavioral performance, the loss of dopaminergic neurons, the reduction of TH positive, and the increase of α-synuclein in both MPTP-treated mice and zebrafish models. In both ethological and ecological experiments, the activity of 5b was confirmed better than ATD or ATD/GA combination, and was almost equal to the positive selegiline. In vivo and in vitro, 5b is shown to reverse the ascend of NR1 and i-NOS levels. This candidate was also demonstrated the activity to down-regulated MPTP-increased Ca2+ influx in SH-SY5Y cells in a steep and sharp mode. It is displayed that 5b exerts neuroprotective effect partly by activating the PI3K/Akt signaling pathway. Taken all together, our data support that 5b is a more promising agent against PD than ATD.

Young-onset colon cancer among people living with HIV in metropolitan Atlanta.

PURPOSE: Colon cancer is a leading cause of cancer-related morbidity and mortality in the USA. We sought to better characterize colon cancer among a predominantly Black cohort with and without HIV. METHODS: We retrospectively reviewed all patients (n = 1482) diagnosed with colon cancer between 2015 and 2019 at a large urban tertiary teaching hospital using ICD-9 and ICD-10 codes. In this cohort, 114 (7.7%) of the patients also had HIV. Descriptive summaries were performed for gender, age, race/ethnicity, insurance status, tobacco/alcohol use, and BMI. RESULTS: Among patients with colon cancer only, 50.51% (n = 691) were men and 49.49% (n = 677) were women. Among patients with both HIV and colon cancer, 78.95% (n = 90) were men and 21.05% (n = 24) were women (p-value < 0.001). The mean age of the colon cancer patient sample was 61.62 years for those without HIV and 51.31 years for those with HIV (p-value < 0.001). Persons with both HIV and colon cancer were more likely to have a lower BMI (p-value < 0.001) and a history of smoking and alcohol use (p-value < 0.001), compared to patients with colon cancer only. When accounting for BMI, tobacco, and alcohol use, those with HIV were 10 years younger than those without HIV, 95% CI, 7.3-13; p < 0.001. CONCLUSIONS: In this study, HIV positive status was a risk factor for developing colon cancer at a younger age. Larger observational studies with multivariable analysis should be done to better describe the risk of colon cancer and HIV.

Association between BRAF expression in circulating tumor cells and the clinical feature of patients with multiple myeloma.

Multiple myeloma (MM) is the most common hematological malignancy with uncontrolled proliferation of monoclonal plasma cells. Despite treatment improvements, MM remains an incurable disease for most patients. Therefore, promising molecular markers are required for MM treatment decisions. In the present study, we explored the relationship between the BRAF expression in circulating tumor cells (CTCs) and the clinical features of patients with MM. The results showed that CTCs were associated with MM staging, and the expression of BRAF was associated with different CTCs. Moreover, the BRAF gene was correlated with patients' white blood cells, blood albumin levels, and Eastern Cooperative Oncology Group (ECOG) score. BRAF expression positively correlated with total CTCs, hybrid CTCs, and mesenchymal CTCs. Taken together, CTCs tightly correlated with the clinical stages and characteristics of MM. Our findings may provide a promising prognosis biomarker for MM treatment decisions.

Multivariant Transcriptome Analysis Identifies Modules and Hub Genes Associated with Poor Outcomes in Newly Diagnosed Multiple Myeloma Patients.

The molecular mechanisms underlying chemoresistance in some newly diagnosed multiple myeloma (MM) patients receiving standard therapies (lenalidomide, bortezomib, and dexamethasone) are poorly understood. Identifying clinically relevant gene networks associated with death due to MM may uncover novel mechanisms, drug targets, and prognostic biomarkers to improve the treatment of the disease. This study used data from the MMRF CoMMpass RNA-seq dataset (N = 270) for weighted gene co-expression network analysis (WGCNA), which identified 21 modules of co-expressed genes. Genes differentially expressed in patients with poor outcomes were assessed using two independent sample t-tests (dead and alive MM patients). The clinical performance of biomarker candidates was evaluated using overall survival via a log-rank Kaplan-Meier and ROC test. Four distinct modules (M10, M13, M15, and M20) were significantly correlated with MM vital status and differentially expressed between the dead (poor outcomes) and the alive MM patients within two years. The biological functions of modules positively correlated with death (M10, M13, and M20) were G-protein coupled receptor protein, cell-cell adhesion, cell cycle regulation genes, and cellular membrane fusion genes. In contrast, a negatively correlated module to MM mortality (M15) was the regulation of B-cell activation and lymphocyte differentiation. MM biomarkers CTAG2, MAGEA6, CCND2, NEK2, and E2F2 were co-expressed in positively correlated modules to MM vital status, which was associated with MM's lower overall survival.

Contrast study after gastric repair: a review of incidence, outcomes and risk factors at an adult level 1 trauma center.

PURPOSE: The role of contrast study after traumatic gastric repair, continues to be controversial. To that end, we aim to review the incidence, outcomes, and risk factors of patients undergoing contrast study after traumatic gastric repair. METHODS: This was a retrospective review of all trauma patients admitted to a level 1 trauma center that sustained gastric injuries with subsequent repair between 2011 and 2018. Demographics, surgical interventions, complications, and clinical outcomes were evaluated. Statistical analysis included Chi-square/Fisher exact univariate analysis and multivariate logistic regression analysis with a 5% significance level. RESULTS: A total of 233 patients received a gastric repair, of whom 49 (21%) had a contrast study performed. Out of 49 patients with a contrast study, one was found to have a gastric leak. Mean time to contrast study was 6.3 ± 2.7 days. There was no statistically significant difference in post-operative complications between non-contrast and contrast study groups. Multivariate logistic regression analysis demonstrated a lack of statistical significance in clinical risk factors that would lead to obtaining a contrast study. CONCLUSION: Gastric leak after repair is rare and there is no statistically significant difference in clinical outcomes when comparing patients who underwent contrast study to those who did not. Routine contrast study after traumatic gastric repair may not be necessary and further evidence is warranted to determine the risk factors for a selective contrast study.

Short-term aspirin and statin chemoprophylaxis did not reduce the risk of developing advanced adenomatous polyps in Black patients.

BACKGROUND: Chemoprevention of colorectal neoplasia with aspirin and statins is under-investigated in Black patients. Since Black patients suffer disproportionately from colon cancer incidence and mortality compared to other populations, we investigated the utility of aspirin and statin in reducing advanced adenomatous polyp (AAP) risk in Black patients. METHODS: We carried out a retrospective cohort study of screening colonoscopies performed at a large urban academic center from 1/1/2011 through 12/31/2019. We analyzed self-identified Black patients with > 1 colonoscopy and no personal history of either inflammatory bowel disease or colon cancer syndromes. Our primary endpoint was first AAP development after index colonoscopy among Black patients taking both aspirin and a statin compared to those taking one or neither medication. We used multivariate logistic regression modeling to investigate our outcomes. RESULTS: We found data on chemoprophylaxis use in 560 patients. The mean observation period between index colonoscopy and AAP identification was 4 years. AAP developed in 106/560 (19%) of our cohort. We found no difference in AAP risk among Black patients taking both chemoprevention medications compared to partial or no chemoprophylaxis (20% vs 18% respectively, p = 0.49). This finding remained after adjusting for age, body mass index, and tobacco use (odds ratio 1.04, 95% CI 0.65-1.67; p = 0.87). CONCLUSIONS: Short-term aspirin-statin chemoprevention did not reduce the risk of AAP development in our cohort of Black patients. Larger and long-term prospective investigations are needed to investigate the utility of chemoprophylaxis in this population. TRIAL REGISTRATION: Not applicable.

What the Jackson Heart Study Has Taught Us About Diabetes and Cardiovascular Disease in the African American Community: a 20-year Appreciation.

PURPOSE OF REVIEW: The burden of cardiometabolic diseases such as cardiovascular disease (CVD) and type 2 diabetes (T2D) is pronounced among African Americans. Research has shown that behavioral, social, metabolic, psychosocial, and genetic risk factors of CVD and T2D are closely interwoven. Approximately 20 years ago, the Jackson Heart Study (JHS) was established to investigate this constellation of risk factors. RECENT FINDINGS: Findings from neighborhood studies emphasize the importance of social cohesion and physical environment in the context CVD and T2D risk. Socioeconomic status factors such as income and education were significant predictors for CVD and T2D. Behavioral studies indicate that modifiable risk factors such as smoking, physical inactivity, lack of sleep, and poor nutrition are associated with CVD risk and all-cause mortality. Mental health also was found to be associated with CVD and T2D. Genetic influences are associated with disease etiology. This review summarizes the joint contributions of CVD and cardiometabolic risk factors in an African American population.

Bawei Chenxiang Wan Ameliorates Cardiac Hypertrophy by Activating AMPK/PPAR-α Signaling Pathway Improving Energy Metabolism.

Bawei Chenxiang Wan (BCW), a well-known traditional Chinese Tibetan medicine formula, is effective for the treatment of acute and chronic cardiovascular diseases. In the present study, we investigated the effect of BCW in cardiac hypertrophy and underlying mechanisms. The dose of 0.2, 0.4, and 0.8 g/kg BCW treated cardiac hypertrophy in SD rat model induced by isoprenaline (ISO). Our results showed that BCW (0.4 g/kg) could repress cardiac hypertrophy, indicated by macro morphology, heart weight to body weight ratio (HW/BW), left ventricle heart weight to body weight ratio (LVW/BW), hypertrophy markers, heart function, pathological structure, cross-sectional area (CSA) of myocardial cells, and the myocardial enzymes. Furthermore, we declared the mechanism of BCW anti-hypertrophy effect was associated with activating adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)/peroxisome proliferator-activated receptor-α (PPAR-α) signals, which regulate carnitine palmitoyltransferase1ß (CPT-1ß) and glucose transport-4 (GLUT-4) to ameliorate glycolipid metabolism. Moreover, BCW also elevated mitochondrial DNA-encoded genes of NADH dehydrogenase subunit 1(ND1), cytochrome b (Cytb), and mitochondrially encoded cytochrome coxidase I (mt-co1) expression, which was associated with mitochondria function and oxidative phosphorylation. Subsequently, knocking down AMPK by siRNA significantly can reverse the anti-hypertrophy effect of BCW indicated by hypertrophy markers and cell surface of cardiomyocytes. In conclusion, BCW prevents ISO-induced cardiomyocyte hypertrophy by activating AMPK/PPAR-α to alleviate the disturbance in energy metabolism. Therefore, BCW can be used as an alternative drug for the treatment of cardiac hypertrophy.

Increased Risk of Sub-Clinical Blood Lead Levels in the 20-County Metro Atlanta, Georgia Area-A Laboratory Surveillance-Based Study.

Lead (Pb) is a naturally occurring, highly toxic metal that has adverse effects on children across a range of exposure levels. Limited screening programs leave many children at risk for chronic low-level lead exposure and there is little understanding of what factors may be used to identify children at risk. We characterize the distribution of blood lead levels (BLLs) in children aged 0-72 months and their associations with sociodemographic and area-level variables. Data from the Georgia Department of Public Health's Healthy Homes for Lead Prevention Program surveillance database was used to describe the distribution of BLLs in children living in the metro Atlanta area from 2010 to 2018. Residential addresses were geocoded, and "Hotspot" analyses were performed to determine if BLLs were spatially clustered. Multilevel regression models were used to identify factors associated with clinical BBLs (≥5 µg/dL) and sub-clinical BLLs (2 to <5 µg/dL). From 2010 to 2018, geographically defined hotspots for both clinical and sub-clinical BLLs diffused from the city-central area of Atlanta into suburban areas. Multilevel regression analysis revealed non-Medicaid insurance, the proportion of renters in a given geographical area, and proportion of individuals with a GED/high school diploma as predictors that distinguish children with BLLs 2 to <5 µg/dL from those with lower (<2 µg/dL) or higher (≥5 µg/dL) BLLs. Over half of the study children had BLLs between 2 and 5 µg/dL, a range that does not currently trigger public health measures but that could result in adverse developmental outcomes if ignored.

Artemisinin protects endothelial function and vasodilation from oxidative damage via activation of PI3K/Akt/eNOS pathway.

INTRODUCTION: Previous studies showed that artemisinin (ART) may be useful in the protection against the early development of atherosclerosis, but the effects of ART on vasodilation and eNOS remained unclear. OBJECTIVES AND METHODS: In the current study, we investigated the protective effect of ART on endothelial cell injury induced by oxidative stress and its underlying mechanism via MTT assay, Flow Cytometry Assay, Vasodilation study, Western blotting and vivo assay. RESULTS: We found that pretreatment of human umbilical vein endothelial cells (HUVECs) with ART significantly suppressed H2O2-induced cell death by decreasing the extent of oxidation and MDA activity, activating SOD, increasing NO production and inhibiting caspase 3/7 activity. Meanwhile, we also found that ART was able to activate PI3K/Akt/eNOS pathway. PI3K inhibitor LY294002 or Akt kinase specific inhibitor Akt inhibitor VIII blocked the protective effect of ART. To explore the effect of ART in the damage of vasodilation induced by H2O2 in mice, we treated the aortic ring from C57BL/6 mice with H2O2 with or without ART, the results demonstrated that ART ameliorated endothelium-dependent vasodilation damage induced by H2O2. CONCLUSION: Taken together, these data suggest that ART is able to protect endothelial function and vasodilation from oxidative damage, at least in part through activation of PI3K/Akt/eNOS pathway. Our findings indicate that artemisinin maybe as a potential therapeutic agent for patients with atherosclerosis.

FoxO3a suppresses neuropeptide W expression in neuronal cells and in rat hypothalamus and its implication in hypothalamic-pituitary-adrenal (HPA) axis.

FoxO3a, a forkhead family member of transcription factors, is involved in the regulation of cell metabolism, proliferation, differentiation and apoptosis. However, whether FoxO3a participates in the regulation of glucocorticoids induced-hypothalamic-pituitary-adrenal (HPA) dysfunction is still unknown. Our present results indicate that dexamethasone(DEX) increased FoxO3a expression in PC12 and hypothalamic neuronal cultures in correlation to reduced expression of NPW, a process that could be blocked by GR2 antagonist. DEX restrained the phosphorylation of Akt and FoxO3a, but not ERK1/2 phosphorylation, resulting with FoxO3a nuclear localization. Overexpression of FoxO3a inhibited NPW expression, while FoxO3a knockdown by siRNA had the opposite effect. The regulatory region of NPW promoter contains multiple FoxO3a binding sites, and FoxO3a bonding to these sites inhibited its transcriptional activity. In a rat model, chronic administration of corticosterone reduced animals' body weight and sucrose consumption and caused stress- depression like behavior. Corticosterone treatment induced a marked increase in FoxO3a levels, while decreased the expression of NPW protein in the hypothalamus. Immunofluorescent double labeling demonstrated that FoxO3a and NPW were collocated in the hypothalamus. Taken together, these data indicate that NPW is a new direct downstream target gene of FoxO3a. FoxO3a suppressed the transcription of NPW and modulated glucocorticoids-induced HPA dysfunction by directly regulating the expression of NPW. Thus, present findings suggest that FoxO3a and NPW may be potential therapeutic targets for endocrine and psychiatric disorders.

The role of FOXOs and autophagy in cancer and metastasis-Implications in therapeutic development.

Autophagy is a highly conserved intracellular degradation process that plays a crucial role in cell survival and stress reactions as well as in cancer development and metastasis. Autophagy process involves several steps including sequestration, fusion of autophagosomes with lysosomes and degradation. Forkhead box O (FOXO) transcription factors regulate the expression of genes involved in cellular metabolic activity and signaling pathways of cancer growth and metastasis. Recent evidence suggests that FOXO proteins are also involved in autophagy regulation. The relationship among FOXOs, autophagy, and cancer has been drawing attention of many who work in the field. This study summarizes the role of FOXO proteins and autophagy in cancer growth and metastasis and analyzes their potential roles in cancer disease management.

Pristimerin-induced uveal melanoma cell death via inhibiting PI3K/Akt/FoxO3a signalling pathway.

Uveal melanoma (UM) is a highly invasive intraocular malignancy with high mortality. Presently, there is no FDA-approved standard for the treatment of metastatic UM. Pristimerin is a natural quinine methide triterpenoid compound with anti-angiogenic, anti-cancer and anti-inflammatory activities. However, Pristimerin potential cytotoxic effect on UM was poorly investigated. In the present study, we found the migration and invasion of UM-1 cells were inhibited by Pristimerin which also caused a rapid increase of ROS, decreased mitochondrial membrane potential, induced the accumulation of cells in G0/G1 phase, ending with apoptotic cell death. Pristimerin inhibited Akt and FoxO3a phosphorylation and induced nuclear accumulation of FoxO3a in UM-1 cells, increased the expression of pro-apoptotic proteins Bim、p27Kip1 , cleaved caspase-3, PARP and Bax, and decreased the expression of Cyclin D1 and Bcl-2. LY294002 or Akt-siRNA inhibited the PI3K/Akt/FoxO3a pathway and promoted the Pristimerin-induced apoptosis, while Pristimerin effects were partially abolished in FoxO3a knockdown UM-1 cell cultures. Taken together, present results showed that Pristimerin induced apoptotic cell death through inhibition of PI3K/Akt/FoxO3a pathway in UM-1 cells. These findings indicate that Pristimerin may be considered as a potential chemotherapeutic agent for patients with UM.

Dihydromyricetin protects HUVECs of oxidative damage induced by sodium nitroprusside through activating PI3K/Akt/FoxO3a signalling pathway.

The damage of vascular endothelial cells induced by oxidative stress plays an important role in the pathogenesis of atherosclerosis. Dihydromyricetin (DMY) is considered as a natural antioxidant. However, the mechanism of DMY on endothelial cell injury induced by oxidative stress remains unclear. In this study, we found that DMY could reduce the oxidative damage of HUVECs induced by sodium nitroprusside (SNP), HUVECs pre-treated with DMY suppressed SNP-induced apoptosis by reduced ROS overproduction of intracellular, decreased MDA level and elevated the superoxide dismutase activity. Meanwhile, we found that DMY could promote the expression of phosphorylated FoxO3a and Akt, and affect the nuclear localization of FoxO3a, when treated with the PI3K inhibitor LY294002, the effect of DMY was blocked. These data suggest that DMY protects HUVECs from oxidative stress by activating PI3K/Akt/FoxO3a signalling pathway. Therefore, DMY may have great therapeutic potential as a new drug for atherosclerosis.

Automatic Anatomy Recognition using Neural Network Learning of Object Relationships via Virtual Landmarks.

The recently developed body-wide Automatic Anatomy Recognition (AAR) methodology depends on fuzzy modeling of individual objects, hierarchically arranging objects, constructing an anatomy ensemble of these models, and a dichotomous object recognition-delineation process. The parent-to-offspring spatial relationship in the object hierarchy is crucial in the AAR method. We have found this relationship to be quite complex, and as such any improvement in capturing this relationship information in the anatomy model will improve the process of recognition itself. Currently, the method encodes this relationship based on the layout of the geometric centers of the objects. Motivated by the concept of virtual landmarks (VLs), this paper presents a new one-shot AAR recognition method that utilizes the VLs to learn object relationships by training a neural network to predict the pose and the VLs of an offspring object given the VLs of the parent object in the hierarchy. We set up two neural networks for each parent-offspring object pair in a body region, one for predicting the VLs and another for predicting the pose parameters. The VL-based learning/prediction method is evaluated on two object hierarchies involving 14 objects. We utilize 54 computed tomography (CT) image data sets of head and neck cancer patients and the associated object contours drawn by dosimetrists for routine radiation therapy treatment planning. The VL neural network method is found to yield more accurate object localization than the currently used simple AAR method.

IGF-1-Mediated Survival from Induced Death of Human Primary Cultured Retinal Pigment Epithelial Cells Is Mediated by an Akt-Dependent Signaling Pathway.

Degeneration of the human retinal pigmented epithelium (hRPE) is involved in several eye disorders such as age-related macular degeneration (AMD). In this study, we investigated the protective effect of IGF-1 on human primary cultured RPE cells and its underlying mechanism. IGF-1 dose- and time-dependently promoted the survival of RPE cells from serum deprivation. Western blot showed that IGF-1 stimulated the activation of the PI3K/Akt and MAPK pathways in hRPE. Inhibition of the PI3K/Akt pathway by the PI3K-specific inhibitor, LY294002 or inhibition of Akt by Akt-specific inhibitors Akt inhibitor VIII or SN-38, or downregulation Akt with siRNA specific for Akt blocked the effect of IGF-1 on hRPE. In contrast, blockade of the MAPK pathway with a specific inhibitor PD98059 had no effect. Interestingly, vitreous IGF-1 injection reversed the inhibitory effect of light exposure (a dry AMD model) on both a wave and b wave. Immunocytochemistry showed that vitreous IGF-1 injections promoted the survival of RPE cells in rat retina and the expression of RPE65 in RPE cells from light injury. These results indicate that IGF-1 is able to protect hRPE cell from different insults in vivo and in vitro. Further detailed studies may lead the way to a therapeutic intervention for retinal diseases in which cell death is an underlying contributory mechanism.

Forkhead box protein O3 suppresses uveal melanoma development by increasing the expression of Bcl­2­like protein 11 and cyclin­dependent kinase inhibitor 1B.

Forkhead box protein O3 (FoxO3a) is a forkhead box family transcription factor which serves an important role in a number of biological functions, including tumor growth. A previous study indicated that FoxO3a serves a role in insulin like growth factor­induced growth, migration and invasion of uveal melanoma (UM) cells; however, whether FoxO3a is associated with the development and formation of UM remains unknown. In the present study, the role of FoxO3a in UM development and formation was investigated by modulating the expression of FoxO3a in a human UM cell line. The results of the present study demonstrated that FoxO3a overexpression in UM cells inhibited cell proliferation and promoted cellular apoptosis, leading to an accumulation of cells at the G1 cell cycle phase. Western blot analysis demonstrated that FoxO3a overexpression increased the transcription and protein expression of Bcl­2­like protein 11 and cyclin­dependent kinase inhibitor 1B, and inhibited cyclin D1 transcription and expression. The opposite effects were observed when FoxO3a was knocked down in UM cells. The results of the present study indicated that FoxO3a may exhibit a negative role in UM development and formation, which is consistent with its role as a tumor suppressor.

Insulin-like growth factor-1 activates PI3K/Akt signalling to protect human retinal pigment epithelial cells from amiodarone-induced oxidative injury.

BACKGROUND AND PURPOSE: Amiodarone is one of the most effective anti-arrhythmic drugs available, but its clinical applications are limited by toxic side effects including optic toxicity. The purpose of this study was to investigate the toxic effect of amiodarone on D407 cells (a human retinal pigmented epithelial (RPE) cell line) and the mechanisms of the protective effect of insulin-like growth factor-1 (IGF-1). EXPERIMENTAL APPROACH: The involvement of the kinases, Akt and ERK, was analysed by Western blot. Intracellular accumulation of ROS was measured using fluorophotometric quantification. A pharmacological approach with inhibitors was used to investigate the pathways involved in the protective action of IGF-1. KEY RESULTS: Amiodarone concentration-dependently augmented the production of ROS, lipid peroxidation and apoptosis in D407 cells. IGF-1 time- and concentration-dependently reversed these effects of amiodarone and protected D407 cells from amiodarone-mediated toxicity. Amiodarone inhibited the pAkt but not pErk, and IGF-1 reversed this inhibitory effect of amiodarone. However, IGF-1 failed to suppress amiodarone-induced cytotoxicity in the presence of PI3K/Akt inhibitor LY294002 suggesting the direct involvement of the PI3K/Akt pathway. Furthermore, in vivo rat flash electroretinogram (FERG) recordings showed that IGF-1 reverses the amiodarone-induced decrease in a- and b-waves. The immunocytochemistry findings confirmed that vitreous IGF-1 injections promote the survival of RPE cells in rat retina treated with amiodarone. CONCLUSION AND IMPLICATIONS: IGF-1 can protect RPE cells from amiodarone-mediated injury via the PI3K/Akt pathway in vivo and in vitro. IGF-1 has potential as a protective drug for the prevention and treatment of amiodarone-induced optic toxicity.

The oxidized phospholipid POVPC impairs endothelial function and vasodilation via uncoupling endothelial nitric oxide synthase.

Endothelial dysfunction is an early stage of atherosclerosis. We recently have shown that 25-hydroxycholesterol found in atherosclerotic lesions could impair endothelial function and vasodilation by uncoupling and inhibiting endothelial nitric oxide synthase (eNOS). 1-Palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine (POVPC), the oxidation product of oxidized low-density lipoprotein, is another proinflammatory lipid and has also been found in atherosclerotic lesions. However, whether POVPC promotes atherosclerosis like 25-hydroxycholesterol remains unclear. The purpose of this study was to explore the effects of POVPC on endothelial function and vasodilation. Human umbilical vein endothelial cells (HUVECs) were incubated with POVPC. Endothelial cell proliferation, migration and tube formation were measured. Nitric oxide (NO) production and superoxide anion generation (O2-) were determined. The expression and phosphorylation of endothelial nitric oxide synthase (eNOS), AKT, PKC-ßII and P70S6K as well as the association of eNOS and heat shock protein 90 (HSP90) were detected by immunoblotting and immunoprecipitation. Endothelial cell apoptosis was monitored by TUNEL staining. The expression of Bcl-2, Bax, and Cleaved Caspase 3 were detected by immunoblotting. Finally, aortic ring from C57BL6 mice were isolated and treated with POVPC and the endothelium-dependent vasodilation was evaluated. POVPC significantly inhibited HUVECs proliferation, migration, tube formation, decreased NO production but increased O2- generation. POVPC inhibited the phosphorylation of Akt and eNOS at Ser1177, increased activation of PKC-ßII, P70S6K and the phosphorylation of eNOS at Thr495, reduced the association of HSP90 with eNOS. Meanwhile, POVPC induced endothelial cell apoptosis by inhibiting Bcl-2 expression, increasing Bax and cleaved caspase-3 expressions as well as caspase-3 activity and impaired endothelium-dependent vasodilation. These data demonstrated that POVPC impaired endothelial function by uncoupling and inhibiting eNOS as well as by inducing endothelial cell apoptosis. Therefore, POVPC may play an important role in the development of atherosclerosis and may be considered as a potential therapeutic target for atherosclerosis.