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2.
Ophthalmology ; 122(12): 2490-6, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26435335

ABSTRACT

PURPOSE: To evaluate the association of statin use with progression of age-related macular degeneration (AMD). DESIGN: Preplanned, prospective cohort study within a controlled clinical trial of oral supplementation for age-related eye diseases. PARTICIPANTS: Age-Related Eye Disease Study 2 (AREDS2) participants, aged 50 to 85 years. METHODS: Factors, including age, gender, smoking status, aspirin use, and history of diabetes, hypertension, heart disease, angina, and stroke-all known to be associated with statin use-were included in a logistic regression model to estimate propensity scores for each participant. Age-adjusted proportional hazards regression models, with and without propensity score matching, were performed to evaluate the association of statin use with progression to late AMD. Analyses adjusting for the competing risk of death were also performed. MAIN OUTCOME MEASURES: Baseline and annual stereoscopic fundus photographs were assessed centrally by masked graders for the development of late AMD, either neovascular AMD or geographic atrophy (GA). RESULTS: Of the 3791 participants (2462 with bilateral large drusen and 1329 with unilateral late AMD at baseline), 1659 (43.8%) were statin users. The overall analysis, with no matching of propensity scores and no adjustment for death as a competing risk, showed that statin use was not associated with progression to late AMD (hazard ratio [HR], 1.08; 95% confidence interval [CI], 0.83-1.41; P = 0.56). When matched for propensity scores and adjusted for death as a competing risk, the result was not statistically significant (HR, 0.81; 95% CI, 0.55-1.20; P = 0.29). Furthermore, subgroup analyses of persons with or without late AMD at baseline and the various components of late AMD (neovascular AMD, central GA, or any GA) also showed no statistically significant association of statin use with progression to AMD. CONCLUSIONS: Statin use was not statistically significantly associated with progression to late AMD in the AREDS2 participants, and these findings are consistent with findings in the majority of previous studies. Statins have been demonstrated to reduce the risk of cardiovascular disease, but our data do not provide evidence of a beneficial effect on slowing AMD progression.


Subject(s)
Geographic Atrophy/diagnosis , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Wet Macular Degeneration/diagnosis , Aged , Aged, 80 and over , Cardiovascular Diseases/drug therapy , Dietary Supplements , Disease Progression , Fatty Acids, Omega-3/administration & dosage , Female , Follow-Up Studies , Geographic Atrophy/epidemiology , Geographic Atrophy/physiopathology , Humans , Incidence , Lutein/administration & dosage , Male , Middle Aged , Proportional Hazards Models , Prospective Studies , Risk Factors , Visual Acuity , Wet Macular Degeneration/epidemiology , Wet Macular Degeneration/physiopathology , Zeaxanthins/administration & dosage
3.
Ophthalmology ; 122(10): 2053-62, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26253372

ABSTRACT

PURPOSE: We investigate whether ocular and person-based characteristics were associated with dark adaptation (DA). DESIGN: Cross-sectional, single-center, observational study. PARTICIPANTS: One hundred sixteen participants older than 50 years of age with a range of age-related macular degeneration (AMD) severity. METHODS: Participants underwent best-corrected visual acuity (BCVA) testing, ophthalmoscopic examination, and multimodal imaging. Presence of reticular pseudodrusen (RPD) was assessed by masked grading of fundus images and was confirmed with optical coherence tomography. Eyes also were graded for AMD features (drusen, pigmentary changes, late AMD) to generate person-based AMD severity groups. One eye was designated the study eye for DA testing. Nonparametric statistical testing was performed on all comparisons. MAIN OUTCOME MEASURES: The primary outcome of this study was the rod intercept time (RIT), which is defined as the time for a participant's visual sensitivity to recover to a stimulus intensity of 5×10(-3) cd/m(2) (a decrease of 3 log units), or until a maximum test duration of 40 minutes was reached. RESULTS: A total of 116 study eyes from 116 participants (mean age, 75.4±9.4 years; 58% female) were analyzed. Increased RIT was associated significantly with increasing AMD severity, increasing age (r = 0.34; P = 0.0002), decreasing BCVA (r = -0.54; P < 0.0001), pseudophakia (P = 0.03), and decreasing subfoveal choroidal thickness (r = -0.27; P = 0.003). Study eyes with RPD (15/116 [13%]) had a significantly greater mean RIT compared with eyes without RPD in any AMD severity group (P < 0.02 for all comparisons), with 80% reaching the DA test ceiling. CONCLUSIONS: Impairments in DA increased with age, worse visual acuity, presence of RPD, AMD severity, and decreased subfoveal choroidal thickness. Analysis of covariance found the multivariate model that best fit the data included age, AMD group, and presence of RPD (R(2) = 0.56), with the presence of RPD conferring the largest parameter estimate.


Subject(s)
Dark Adaptation/physiology , Macular Degeneration/physiopathology , Retinal Drusen/physiopathology , Vision Disorders/physiopathology , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Humans , Macular Degeneration/diagnosis , Male , Middle Aged , Multimodal Imaging , Ophthalmoscopy , Retinal Drusen/diagnosis , Severity of Illness Index , Vision Disorders/diagnosis , Visual Acuity/physiology
4.
Ann Surg ; 257(3): 427-32, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23388351

ABSTRACT

OBJECTIVE: Alvimopan was approved by the Food and Drug Administration in May 2008 and has been shown to accelerate gastrointestinal recovery after colectomy. Our independent study evaluated alvimopan as it is used in actual hospital practice in the state of Michigan. We hypothesized that alvimopan significantly decreases incidence of prolonged ileus and reduces length of stay (LOS) in patients who have undergone colectomy. METHODS: We identified 4749 patients from the Michigan Surgical Quality Collaborative (N = 28 hospitals) database between August 2007 and December 2010 who underwent elective colectomy operations. A total of 528 patients received alvimopan both pre- and postoperatively. We first selected a control group of patients from hospitals that had never administered alvimopan (n = 1833) and used propensity matching to manage differences in patient demographics and clinical characteristics. To control for hospital and surgeon characteristics, we then performed a sensitivity analysis, using a separate group of historical control patients treated before May 2008 in hospitals that would later administer alvimopan (n = 270). The Fisher exact test was used to compare complication rates, and the Student t test was used to compare LOS. RESULTS: Patients who received alvimopan had significantly lower incidence of prolonged ileus (2.3% vs 7.9%; P < 0.001) and a significantly shorter LOS (4.84 ± 4.54 vs 6.40 ± 4.45 days; P < 0.001) than control patients in hospitals that had never administered alvimopan. No differences were noted in these outcomes using sensitivity analysis. CONCLUSION: This study suggests that the actual utilization of alvimopan leads to a reduction in prolonged ileus and LOS in patients who underwent colectomy. By accelerating postoperative recovery, alvimopan has the potential to benefit patients and health care systems by improving outcomes, ensuring patient comfort, and reducing cost.


Subject(s)
Colectomy/adverse effects , Ileus/prevention & control , Piperidines/administration & dosage , Colonic Diseases/surgery , Dose-Response Relationship, Drug , Female , Gastrointestinal Agents , Humans , Ileus/epidemiology , Ileus/etiology , Incidence , Laparoscopy , Length of Stay/trends , Male , Michigan/epidemiology , Middle Aged , Postoperative Period , Recovery of Function/drug effects , Treatment Outcome
5.
J AAPOS ; 27(2): 93.e1-93.e4, 2023 04.
Article in English | MEDLINE | ID: mdl-36801243

ABSTRACT

PURPOSE: To report clinical outcomes and risk factors for glaucoma in children and adolescents referred for increased cup:disk ratios (CDRs) to a tertiary referral center. METHODS: This retrospective, single-center study examined all pediatric patients evaluated for increased CDR at Wills Eye Hospital. Patients who had previous known ocular disease were excluded. Demographic data, including sex, age, and race/ethnicity were recorded, as were baseline and follow-up ophthalmic examination findings, including intraocular pressure (IOP), CDR, diurnal curve, gonioscopy findings, and refractive error. Risks of glaucoma diagnosis based on these data were analyzed. RESULTS: A total of 167 patients were included, of whom 6 were found to have glaucoma. Despite more than 2 years' follow-up on 61 patients, all glaucoma patients were identified within the first 3 months of evaluation. Baseline IOP was statistically significantly higher in glaucomatous patients than nonglaucomatous patients (28 ± 7 vs 15 ± 4, resp. [P = 0.0002]), as was maximum IOP on diurnal curve (24 ± 3 vs 17 ± 3 [P = 0.0005]). CONCLUSIONS: In our study cohort, diagnosis of glaucoma was apparent in the first year of evaluation. Baseline IOP and maximal IOP on diurnal curve were found to be statistically significantly associated with glaucoma diagnosis in pediatric patients referred for increased CDR.


Subject(s)
Glaucoma, Open-Angle , Glaucoma , Humans , Adolescent , Child , Retrospective Studies , Tertiary Care Centers , Glaucoma/diagnosis , Intraocular Pressure
7.
Ophthalmol Glaucoma ; 4(2): 139-148, 2021.
Article in English | MEDLINE | ID: mdl-32931948

ABSTRACT

PURPOSE: To explore the demographic and clinical variables associated with intraocular pressure (IOP) lowering after cataract extraction (CE) alone or CE in combination with the iStent (Glaukos Corporation) placement (CE+IS). DESIGN: Retrospective data extraction and survival analysis of consecutive patients identified over a 2-year period. PARTICIPANTS: Patients with mild to moderate glaucoma who underwent CE (48 eyes of 32 patients) or CE+IS (61 eyes of 37 patients) were analyzed. METHODS: Inability to reduce the number of medications or the IOP by at least 20% compared with baseline on 2 consecutive visits was considered surgical failure. Using Cox proportional hazards models, survival analysis was performed, and demographic and clinical variables were evaluated as risk factors. MAIN OUTCOME MEASURES: Time to failure after surgical procedure. RESULTS: CE+IS had lower odds of failure than CE alone (hazard ratio [HR], 2.01; P = 0.047). In White patients, CE+IS showed greater odds of success compared with CE alone (HR, 2.86; P = 0.007). For non-White patients, no difference was found in the outcomes for the 2 procedures (HR, 0.59; P = 0.48). In the multivariate analysis, non-White race (HR, 8.75; P = 0.0002) and longer axial length (HR, 1.61; P = 0.03) were associated with greater hazard of failure after CE+IS. In the CE group, greater odds of failure were associated with steeper corneal curvature (HR, 1.74; P = 0.008), shallower anterior chamber (HR, 0.22; P = 0.008), and longer axial length (HR, 1.58; P = 0.01). CONCLUSIONS: Addition of the iStent to CE improved the duration of IOP lowering in White patients, but not in non-White patients. Associations between IOP lowering after CE and biometric parameters may allow for leveraging these clinical parameters for better case selection for these procedures.


Subject(s)
Cataract Extraction , Glaucoma Drainage Implants , Glaucoma, Open-Angle , Phacoemulsification , Glaucoma, Open-Angle/surgery , Humans , Intraocular Pressure , Phacoemulsification/adverse effects , Retrospective Studies
8.
Neurochem Res ; 35(1): 152-61, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19685289

ABSTRACT

Resveratrol is a naturally occurring polyphenolic compound highly enriched in grapes, peanuts, red wine, and a variety of food sources. Sulforaphane belongs to the family of isothiocyanates and is highly enriched in cruciferous vegetables. Our previous study showed that resveratrol, when used at high concentrations, inhibited cell proliferation, caused the cell cycle arrest and induced apoptotic cell death in glioma cells. In the current study, we tested the effect of combination treatment with resveratrol and sulforaphane, when both were used at low concentrations, on cell proliferation, migration and death in human U251 glioma cells. Our study shows that combination treatment with resveratrol and sulforaphane inhibits cell proliferation and migration, reduces cell viability, induces lactate dehydrogenase release, decreases pro-survival Akt phosphorylation and increases caspase-3 activation. The use of combination of bioactive food components, such as resveratrol and sulforaphane, may be a viable approach for the treatment of glioma.


Subject(s)
Apoptosis/drug effects , Glioma/pathology , Stilbenes/pharmacology , Thiocyanates/pharmacology , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Isothiocyanates , Resveratrol , Sulfoxides
9.
Pediatr Transplant ; 14(1): 132-7, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19413719

ABSTRACT

Occlusive PVT concurrent with chronic liver disease is a common clinical entity among pediatric patients referred for transplantation. The natural history of PVT is unknown. Our aim was to determine, using a retrospective cohort design, if children under 13 yr with chronic liver disease and concomitant PVT have an increased mortality risk prior to and after transplantation. A total of 203 patients were included in the study. Nearly 10% of the population had PVT (n = 19); 63.2% of PVT patients (5.9% of total cohort) underwent liver transplantation (n = 12). PVT patients tended to be younger than non-PVT patients at evaluation (1.94 +/- 3.51 vs. 3.79 +/- 4.11, p = 0.059). Clinical and demographic factors were similar between the two groups. Regarding survival, four PVT patients died, of which two had undergone transplantation. Kaplan-Meier analyses indicated that PVT and non-PVT patients had similar survival from the time of evaluation, on the waiting list, and after transplant. Although limited by sample size, our study suggests that a diagnosis of PVT does not increase the mortality risk for children waiting for a liver transplant. Further study is needed to discern variations in mortality risk that may occur in the pediatric chronic liver disease population with PVT.


Subject(s)
Kidney Failure, Chronic/mortality , Portal Vein , Venous Thrombosis/mortality , Child, Preschool , Female , Follow-Up Studies , Humans , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/surgery , Kidney Transplantation , Male , Postoperative Period , Preoperative Period , Prognosis , Retrospective Studies , Risk Factors , Survival Rate/trends , United States/epidemiology , Venous Thrombosis/complications , Venous Thrombosis/surgery
10.
World J Surg ; 34(11): 2524-9, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20703470

ABSTRACT

With the recent regulations limiting resident work hours, it has become more important to understand how residents spend their time. The volume and content of the pages they receive provide a valuable source of information that give insight into their workload and help identify inefficiencies in hospital communication. We hypothesized that above a certain workload threshold, paging data would suggest breakdowns in communication and implications for quality of care. All pages sent to six general surgery interns at the University of Michigan over the course of one academic year (7/1/2008-6/30/2009) were retrospectively categorized by sender type, message type, message modifier, and message quality. Census, discharge, and admission information for each intern service were also collected, and intern duties were further analyzed with respect to schedule. "On-call" days were defined as days on which the intern bore responsibility for care of all admitted floor patients. The interns received a total of 9,843 pages during the study period. During on-call shifts, each intern was paged an average of 57 ± 3 times, and those on non-call shifts received an average of 12 ± 3 pages. Floor/intensive care unit (ICU) nurses represented 32% of the page volume received by interns. Interestingly, as patient volume increased, there was a decrease in the number of pages received per patient. By contrast, at higher patient volumes, there was a trend toward an increasing percentage of urgent pages per patient. At high intern workloads, our data suggest no major communication breakdowns but reveal the potential for inferior quality of care.


Subject(s)
Hospital Communication Systems/statistics & numerical data , Internship and Residency , Quality of Health Care , Workload/statistics & numerical data , Humans , Retrospective Studies
11.
J Pediatr Ophthalmol Strabismus ; 57: e68-e70, 2020 Aug 19.
Article in English | MEDLINE | ID: mdl-32816046

ABSTRACT

Recurrent painful ophthalmoplegic neuropathy, or ophthalmoplegic migraine, is characterized by recurrent cranial nerve paresis following headache. Imaging may demonstrate cranial nerve enhancement during episodes, but absence of structural lesions is required for diagnosis. [J Pediatr Ophthalmol Strabismus. 2020;57:e68-e70.].


Subject(s)
Cranial Nerve Neoplasms/diagnosis , Diagnostic Imaging/methods , Neurilemmoma/diagnosis , Tolosa-Hunt Syndrome/diagnosis , Diagnosis, Differential , Female , Humans , Recurrence
12.
Ophthalmic Genet ; 41(4): 381-385, 2020 08.
Article in English | MEDLINE | ID: mdl-32506993

ABSTRACT

BACKGROUND: Sjögren-Larsson syndrome (SLS) is a rare genetic neurocutaneous disease caused by mutations in ALDH3A2 that results in deficiency of fatty aldehyde dehydrogenase and accumulation of fatty aldehydes and alcohols. The disease is associated with ichthyosis, spasticity, and intellectual disability. Patients exhibit a characteristic retinopathy with macular crystalline inclusions that first appear in early childhood and increase with age. Once formed, the inclusions are thought to be inert and irreversible. We sought to document how the crystalline inclusions change over time. MATERIALS AND METHODS: Serial retinal photographs of 4 SLS subjects (9-23 years old) were taken over a period of 1-3 years. Images were compared by visual inspection and analyzed using ImageJ/Fiji software to observe changes. RESULTS: Visual inspection of retinal photographs of SLS subjects taken over time demonstrated distinctive changes in crystalline inclusions. New inclusions were formed and some established inclusions regressed. These changes were conveniently demonstrated with software-based photographic image analysis. CONCLUSIONS: We conclude that macular inclusions in SLS are not simply inert deposits, but are dynamic structures that form over time and are subject to remodeling. This conclusion provides new insight into the interplay between the metabolic defect and retinal pathology in SLS, and raises the potential for new therapeutic approaches to reverse some aspects of the maculopathy.


Subject(s)
Aldehyde Oxidoreductases/genetics , Macula Lutea/physiopathology , Macular Degeneration/physiopathology , Mutation , Sjogren-Larsson Syndrome/pathology , Adolescent , Adult , Child , Female , Humans , Longitudinal Studies , Male , Pedigree , Phenotype , Sjogren-Larsson Syndrome/etiology , Sjogren-Larsson Syndrome/genetics , Young Adult
13.
J Exp Ther Oncol ; 8(1): 25-33, 2009.
Article in English | MEDLINE | ID: mdl-19827268

ABSTRACT

Resveratrol (trans-3,4', 5-trihydroxystilbene) is a naturally occurring polyphenolic compound that has antiinflammatory, antioxidant, neuroprotective properties and acts as a chemopreventive agent. Resveratrol causes cell cycle arrest and induces apoptotic cell death in various types of cancer cells. In the current studies, the effect of resveratrol on phosphoinositide kinase-3 (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway was examined in human U251 glioma cells. Resveratrol decreased both the expression and phosphorylation of Akt. Inhibitors of PI3K (LY294002) and Akt (SH-6) enhanced resveratrol-induced LDH release and caspase-3 activation. Resveratrol reduced phosphorylation of ribosomal protein S6 and the mTOR inhibitor rapamycin further enhanced resveratrol-induced cell death. These results suggest that the downregulation of PI3K/Akt/mTOR signaling pathways may be an important mediator in resveratrol-induced apoptosis in glioma cells.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Glioma/drug therapy , Phosphoinositide-3 Kinase Inhibitors , Protein Kinases/drug effects , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Signal Transduction/drug effects , Stilbenes/pharmacology , Caspase 3/metabolism , Cell Line, Tumor , Cyclin D1/antagonists & inhibitors , Dose-Response Relationship, Drug , Down-Regulation , Glioma/pathology , Humans , Resveratrol , TOR Serine-Threonine Kinases
14.
Clin Ophthalmol ; 12: 1003-1009, 2018.
Article in English | MEDLINE | ID: mdl-29881255

ABSTRACT

PURPOSE: The treatment of retinopathy of prematurity (ROP) is not standardized and can vary significantly between providers. This study aims to determine preferred practices in treating ROP by globally surveying pediatric ophthalmologists. METHODS: Between January and February 2017, an international pediatric ophthalmology interest group was invited to complete an anonymous survey of 18 questions. The main objectives were to determine the preferred first line of treatment for ROP, the preferred dosage of intravitreal bevacizumab (IVB) used, and the outcome and possible complications following bevacizumab injection. RESULTS: Out of 101 pediatric ophthalmologists, 72 (71.8%) stated that they had direct involvement in the treatment of ROP. When presented with type 1 ROP which requires treatment, 69 ophthalmologists (68.3%) stated that they prefer laser treatment over bevacizumab, and 33 ophthalmologists (32.7%) stated they would recommend bevacizumab as a first choice. Ninety-three ophthalmologists (92.1%) reported the success of 1 laser treatment between 75% and 100%, and 35 ophthalmologists (34.7%) perceive bevacizumab to be 75%-100% successful. Half dose of adult-prescribed bevacizumab at 0.625 mg/0.05 mL was preferred by 47 of the ophthalmologists (46.5%). No cases of endophthalmitis were reported with intravitreal injection. CONCLUSION: Laser photoablation remains the preferred mode of treatment for ROP among surveyed ophthalmologists across the world. Though bevacizumab is currently being used, this form of treatment is not as common, primarily due to the unknown safety profile and potential long-term ramifications of the drug.

15.
J AAPOS ; 21(4): 337-339.e2, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28694215

ABSTRACT

Whereas most retinoblastomas are seen as intraocular tumors, the diffuse infiltrating type is distinguished by a horizontal growth along the retina with minimal vertical growth. These findings can resemble other entities and present as a diagnostic challenge. Fluorescein angiography (FA) features of retinoblastoma have been described in the literature; however, to our knowledge, little information is available on the diffuse type. We present FA findings and the clinicopathlogic correlation of 2 patients with diffuse retinoblastoma. Changes observed on FA correlate with the vascular changes observed on histopathology and can therefore be helpful in the diagnosis of atypical retinoblastomas when the clinical presentation is equivocal.


Subject(s)
Retinal Neoplasms/diagnostic imaging , Retinoblastoma/diagnostic imaging , Adolescent , Calcinosis/diagnostic imaging , Calcinosis/pathology , Child, Preschool , Female , Fluorescein Angiography , Humans , Male , Retinal Neoplasms/pathology , Retinoblastoma/pathology
17.
J Am Coll Surg ; 208(6): 1077-84, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19476895

ABSTRACT

BACKGROUND: Smokers with chronic liver disease can become eligible for transplantation, but some insurers refuse reimbursement pending smoking cessation. STUDY DESIGN: Our hypothesis is that liver transplantation candidates and recipients who smoke have inferior survival compared with nonsmokers. Using a retrospective cohort study design, three Cox proportional hazards models were constructed to determine covariate-adjusted mortality from transplantation evaluation and transplantation based on smoking status at evaluation, transplantation, and posttransplantation followup. RESULTS: From 1999 to 2007, 2,260 patients were evaluated. Seven hundred sixty were active smokers, and 1,500 were nonsmokers. Smokers at evaluation were younger (49.3 versus 51.7 years), were more likely to be men (65.9% versus 58.7%), have hepatitis C (54.2% versus 30.1%), have a lower Model for End-Stage Liver Disease score (10.5 versus 12.3), and less likely to receive transplant (12.2% versus 18.6%) (all p < 0.05). The postevaluation multivariate model indicated that substance use, higher Model for End-Stage Liver Disease score, hepatitis C, and older age increased mortality risk (all p < 0.05), and liver transplantation (hazards ratio = 0.986; 95% CI, 0.977 to 0.994) was associated with lower mortality. Smoking was not associated with increased mortality risk at any time point in those evaluated or receiving transplants. CONCLUSIONS: Providers should continue encouraging potential liver transplantation candidates to stop smoking, but insurer-driven mandated smoking cessation might not improve survival.


Subject(s)
Liver Failure/surgery , Liver Transplantation/mortality , Smoking/adverse effects , Comorbidity , Female , Humans , Liver Failure/epidemiology , Male , Middle Aged , Proportional Hazards Models , Retrospective Studies , Smoking/epidemiology , Survival Analysis
18.
J Pharmacol Exp Ther ; 321(2): 616-25, 2007 May.
Article in English | MEDLINE | ID: mdl-17289836

ABSTRACT

Our previous studies have shown that dietary pigment curcumin [1,7-bis(4-hydroxy-3-methoxyphenyl)-1-6-heptadine-3,5-dione; C21H20O6] sensitizes human prostate cancer cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo2L)-induced apoptosis by inhibiting nuclear factor (NF)-kappaB. In the present study, we demonstrate that activated (phosphorylated) Akt kinase plays a pivotal role in regulation of NF-kappaB and sensitization of LNCaP and PC3 prostate cancer cells to TRAIL by curcumin. Curcumin inhibited the expression of phospho-Akt (p-Akt), which was not due to activation of phosphatase and tensin homolog deleted on chromosome 10 phosphatase activity by curcumin. Because NF-kappaB is a downstream target of Akt, we investigated whether inhibition of NF-kappaB by curcumin is mediated through suppression of p-Akt. Data demonstrate that treatment of PC3 cells with SH-6 (JAm Chem Soc 125:1144-1145, 2003), a specific inhibitor of Akt, or transfection with small inhibitory RNA (siRNA)-Akt not only inhibited p-Akt but also abrogated the expression and transcriptional activity of NF-kappaB. Furthermore, overexpression of constitutively active Akt1 in cancer cells prevented the inhibition of NF-kappaB by curcumin. In addition, treatment with SH-6 or transfection with siRNA-Akt sensitized PC3 cells to TRAIL-induced cytotoxicity. On the other hand, SH-6 does not inhibit NF-kappaB or sensitize DU145 cancer cells to TRAIL because these cells do not express p-Akt. Because expression of antiapoptotic Bcl-2, Bcl-xL, and X-chromosome-linked inhibitor of apoptosis protein (XIAP) is regulated by NF-kappaB, both curcumin and SH-6 decreased the levels of these proteins in PC3 cells through inhibition of NF-kappaB. Furthermore, gene silencing of Bcl-2 with siRNA-Bcl-2 sensitized PC3 cells to TRAIL. Collectively, these data define a pathway whereby curcumin sensitizes prostate cancer cells to TRAIL by inhibiting Akt-regulated NF-kappaB and NF-kappaB-dependent antiapoptotic Bcl-2, Bcl-xL, and XIAP.


Subject(s)
Apoptosis/drug effects , Curcumin/pharmacology , NF-kappa B/antagonists & inhibitors , Prostatic Neoplasms/drug therapy , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Signal Transduction/drug effects , TNF-Related Apoptosis-Inducing Ligand/pharmacology , Cell Line, Tumor , Humans , I-kappa B Proteins/metabolism , Male , NF-KappaB Inhibitor alpha , NF-kappa B/physiology , Phosphatidylinositols/pharmacology , Phosphorylation , Prostatic Neoplasms/pathology , RNA, Small Interfering/pharmacology
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