Factors Associated With Attendance for Cardiac Neurodevelopmental Evaluation.

BACKGROUND AND OBJECTIVES: Neurodevelopmental evaluation of toddlers with complex congenital heart disease is recommended but reported frequency is low. Data on barriers to attending neurodevelopmental follow-up are limited. This study aims to estimate the attendance rate for a toddler neurodevelopmental evaluation in a contemporary multicenter cohort and to assess patient and center level factors associated with attending this evaluation. METHODS: This is a retrospective cohort study of children born between September 2017 and September 2018 who underwent cardiopulmonary bypass in their first year of life at a center contributing data to the Cardiac Neurodevelopmental Outcome Collaborative and Pediatric Cardiac Critical Care Consortium clinical registries. The primary outcome was attendance for a neurodevelopmental evaluation between 11 and 30 months of age. Sociodemographic and medical characteristics and center factors specific to neurodevelopmental program design were considered as predictors for attendance. RESULTS: Among 2385 patients eligible from 16 cardiac centers, the attendance rate was 29.0% (692 of 2385), with a range of 7.8% to 54.3% across individual centers. In multivariable logistic regression models, hospital-initiated (versus family-initiated) scheduling for neurodevelopmental evaluation had the largest odds ratio in predicting attendance (odds ratio = 4.24, 95% confidence interval, 2.74-6.55). Other predictors of attendance included antenatal diagnosis, absence of Trisomy 21, higher Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery mortality category, longer postoperative length of stay, private insurance, and residing a shorter distance from the hospital. CONCLUSIONS: Attendance rates reflect some improvement but remain low. Changes to program infrastructure and design and minimizing barriers affecting access to care are essential components for improving neurodevelopmental care and outcomes for children with congenital heart disease.

Neuropsychological Screening in Pediatric Multidisciplinary Clinics: Group Characteristics and Predictive Utility.

OBJECTIVE: To evaluate the feasibility of administering caregiver-report neuropsychological screening measures in pediatric multidisciplinary clinics (MDCs) and investigate predictive utility for cognitive and academic difficulties on follow-up testing. METHOD: The Pediatric Perceived Cognitive Functioning (Peds PCF) and Colorado Learning Difficulties Questionnaire (CLDQ) were administered to caregivers of youth with history of brain tumor (BT), non-central nervous system (CNS) cancer, or Fontan circulation as part of routine neuropsychological consultation in MDCs from 2017 to 2019. We examined cross-sectional differences on screening measures, and relationships between screening and intellectual and academic test performance in a subset who presented for follow-up neuropsychological evaluation. Receiver operating characteristic (ROC) curve analysis was used to identify suggested cut scores on screening measures for predicting who would most benefit from further evaluation. RESULTS: Screening was completed with 192 families. Children with history of non-CNS cancer (n = 29) had fewer parent-reported cognitive and academic concerns compared with either BT (n = 88) or Fontan (n = 75) groups. Peds PCF and CLDQ scores were related to intellectual and academic test performance in the group presenting for neuropsychological evaluation (n = 68). ROC curve analysis identified cut scores across screening measures with maximal sensitivity and specificity for detecting neuropsychological difficulties. CONCLUSIONS: It is feasible to utilize parent rating measures during neuropsychological consultation in pediatric MDCs. The Peds PCF and CLDQ demonstrated sensitivity to intellectual and academic difficulties in children with significant medical histories. Screening may be a helpful tool for pediatric neuropsychologists and other professionals during MDC consultation to inform clinical management.

Is Neurodevelopment Related to Exercise Capacity in Single Ventricle Patients Who Have Undergone Fontan Palliation?

Survivors of palliative surgery for single ventricle heart disease (SVHD) are at risk of poor neurodevelopmental outcomes and reduced exercise capacity. In healthy populations, reduced exercise capacity is related to decreased cognition suggesting a possible relationship between exercise capacity and neurodevelopment. Using cardiopulmonary exercise testing (CPET) and neuropsychological testing (NPT) as indicators of exercise capacity and neurodevelopment, respectively, we hypothesized that in SVHD, higher CPET measures are related to better NPT performance. Patients were retrospectively identified. CPET variables included VO2max, anaerobic threshold, peak heart rate, ventilatory efficiency, and respiratory exchange ratio. NPT instruments were divided into domains measuring attention, executive functioning, adaptive functioning, and emotional functioning. Linear regression was used to test for associations between CPET and NPT. 23 subjects with SVHD met inclusion criteria. On both CPET and NPT, the cohort scored worse than healthy, age-matched subjects. Higher VO2max and anaerobic threshold were associated with better parent-rated overall adaptive functioning (p = 0.01 and p = 0.02, respectively). Higher peak heart rate was related to better sustained visual attention (p = 0.01). In SVHD, CPET measures indicating better exercise capacity were positively associated with a subset of scores on NPT. Larger, multisite studies implementing cardiorespiratory fitness intervention and incorporating cognitive outcome measures will be needed to better characterize the relationship between neurodevelopment and functional capacity in this population. Results may assist in providing anticipatory guidance and optimizing post-Fontan developmental trajectories.

Uncoupling of p97 ATPase activity has a dominant negative effect on protein extraction.

p97 is a highly abundant, homohexameric AAA+ ATPase that performs a variety of essential cellular functions. Characterized as a ubiquitin-selective chaperone, p97 recognizes proteins conjugated to K48-linked polyubiquitin chains and promotes their removal from chromatin and other molecular complexes. Changes in p97 expression or activity are associated with the development of cancer and several related neurodegenerative disorders. Although pathogenic p97 mutations cluster in and around p97's ATPase domains, mutant proteins display normal or elevated ATPase activity. Here, we show that one of the most common p97 mutations (R155C) retains ATPase activity, but is functionally defective. p97-R155C can be recruited to ubiquitinated substrates on chromatin, but is unable to promote substrate removal. As a result, p97-R155C acts as a dominant negative, blocking protein extraction by a similar mechanism to that observed when p97's ATPase activity is inhibited or inactivated. However, unlike ATPase-deficient proteins, p97-R155C consumes excess ATP, which can hinder high-energy processes. Together, our results shed new insight into how pathogenic mutations in p97 alter its cellular function, with implications for understanding the etiology and treatment of p97-associated diseases.

Initiating a Fontan multidisciplinary clinic: Decreasing care variability, improving surveillance, and subsequent treatment of Fontan survivors.

BACKGROUND: Children with single ventricle (SV) heart disease who undergo Fontan operation are at risk for developing multiorgan dysfunction. Although survival has improved, significant comorbidities involving multiple organ systems may develop, requiring evaluation and management by many subspecialists. Using data from an internal survey, we documented high care variability for our Fontan population. We then developed a multidisciplinary clinic, designed and implemented a clinical care pathway to decrease variability of patient assessment. METHODS: After creating a multidisciplinary team and a clinical care pathway, we initiated a multidisciplinary clinic (MDC) where patients could see multiple subspecialists during a single encounter. We then monitored our effectiveness by retrospective chart review to determine care pathway adherence (process measure) and incidence of new diagnoses of end-organ injury (outcome measure) as well interventions implemented. Adherence was analyzed using statistical process control (SPC) charts. RESULTS: Eighty-six patients were seen in the MDC from January 2016 to September 2017. The proportion of patients with appropriate testing increased, related to strong care pathway adherence. A significant amount of novel pathology was diagnosed in all evaluated organ systems, both Fontan-associated comorbidities and general pediatric diagnoses. Subsequent interventions included cardiac catheterization n = 21 (31%) with more than half of these patients undergoing intervention n = 17 (20%), and liver biopsy n = 9 (10%). Additionally, 58 patients (67%) were referred to a neuropsychologist based on perceived clinical need, with n = 34 (40%) undergoing a neuropsychological evaluation. CONCLUSIONS: Children who have undergone Fontan palliation are at risk for developing cardiac and noncardiac comorbidities. Use and adherence to an institutional care pathway resulted in the diagnosis of significant novel pathology and subsequently provided opportunity for intervention.

Oxygen saturations and neurodevelopmental outcomes in single ventricle heart disease.

OBJECTIVES: To evaluate whether the degree of hypoxemia following stage-I and stage-II palliative surgeries predicts neurodevelopmental outcomes at 14 months of age in children with single ventricle congenital heart disease (SVCHD). DESIGN: We analyzed longitudinal data from two Pediatric Heart Network (PHN) randomized controlled trials, with a total of 328 subjects. Oxygen saturations, measured via pulse oximetry, at time of discharge from stage-I and stage-II surgeries were the primary predictors of interest, and Bayley Scales of Infant Development-II (BSID-II) scores at 14 months old were the primary outcome measure. Relevant covariates from previously-published PHN studies were also included in regression models. RESULTS: Oxygen saturations at time of discharge from stage-I and stage-II surgeries were not related to BSID-II scores. Having one or more oxygen saturation measurements below 80% was also not associated with BSID-II scores, and neither was change in oxygen saturations over time. These relationships were not altered by inclusion of relevant covariates. CONCLUSIONS: In this large cohort of children with SVCHD, oxygen saturations post-stage-I and post-stage-II palliation surgeries as measured via pulse oximetry were not associated with neurodevelopmental outcomes at 14 months of age. The relationship between oxygen saturations and neurodevelopment in SVCHD is likely complex, and neurodevelopment is known to be affected by a number of factors. Pulse oximetry may also be an insufficient proxy for cerebral oxygen delivery. Clinically, pulse oximetry readings during the interstage and post-stage-II surgery periods are not a reliable predictor of future neurodevelopmental risk.

Pulmonary Screening in Subjects after the Fontan Procedure.

OBJECTIVES: To review the pulmonary findings of the first 51 patients who presented to our interdisciplinary single-ventricle clinic after undergoing the Fontan procedure. STUDY DESIGN: We performed an Institutional Review Board-approved retrospective review of 51 patients evaluated following the Fontan procedure. Evaluation included history, physical examination, pulmonary function testing, and 6-minute walk. Descriptive statistics were used to describe the population and testing data. RESULTS: Sixty-one percent of the patients had a pulmonary concern raised during the visit. Three patients had plastic bronchitis. Abnormal lung function testing was present in 46% of patients. Two-thirds (66%) of the patients had significant desaturation during the 6-minute walk test. Patients who underwent a fenestrated Fontan procedure and those who underwent unfenestrated Fontan were compared in terms of saturation and 6-minute walk test results. Sleep concerns were present in 45% of the patients. CONCLUSIONS: Pulmonary morbidities are common in patients after Fontan surgery and include plastic bronchitis, abnormal lung function, desaturations with walking, and sleep concerns. Abnormal lung function and obstructive sleep apnea may stress the Fontan circuit and may have implications for cognitive and emotional functioning. A pulmonologist involved in the care of patients after Fontan surgery can assist in screening for comorbidities and recommend interventions.

Predicting changes in adaptive functioning and behavioral adjustment following treatment for a pediatric brain tumor: A report from the Brain Radiation Investigative Study Consortium.

BACKGROUND: Children are at risk for behavioral and adaptive difficulties following pediatric brain tumor. This study explored whether familial/demographic, developmental, diagnostic, or treatment-related variables best predict posttreatment behavioral and adaptive functioning. METHODS: Participants included 40 children (mean age = 12.76 years, SD = 4.01) posttreatment (mean time since diagnosis = 1.99 years, SD = 0.21) for pediatric brain tumor. Parents rated children's behavioral adjustment and adaptive functioning and provided demographic and developmental histories. Diagnostic and treatment-related information was abstracted from medical records. RESULTS: Ratings of adaptive and behavioral functioning approximately 2 years postdiagnosis were within the average range, although the percentage of children exceeding clinical cutoffs for impairment in adaptive skills exceeded expectation, particularly practical skills. Premorbid behavior problems and tumor size predicted posttreatment adaptive functioning. After accounting for adaptive functioning near diagnosis, premorbid behavior problems predicted declines in adaptive functioning 2 years postdiagnosis. After accounting for adjustment near diagnosis, no variables predicted declines in behavioral adjustment. CONCLUSIONS: Children may be vulnerable to reduced adaptive functioning following pediatric brain tumor treatment, especially in practical skills. Assessing prediagnosis functioning and diagnostic and treatment-related variables may improve our ability to predict those at greatest risk, although those factors may be less helpful in identifying children likely to develop behavioral difficulties. Screening of these factors in tertiary care and long-term follow-up settings may improve identification of those at greatest need for support services.

Predictors of adaptive functioning and psychosocial adjustment in children with pediatric brain tumor: a report from the Brain Radiation Investigative Study Consortium.

BACKGROUND: Children are at risk for psychosocial and adaptive morbidities following diagnosis of and treatment for a pediatric brain tumor. This study examined whether familial/demographic, developmental, diagnostic, or treatment-related variables best predict the acute psychosocial adjustment and adaptive functioning of children soon after an initial diagnosis. PROCEDURE: Participants included 56 children (mean age = 10.72, SD = 4.02) newly diagnosed with a pediatric brain tumor. Parents completed background/demographic forms and completed ratings of children's behavioral and emotional symptoms, and adaptive behavior. Diagnostic and treatment-related information was abstracted from medical records. RESULTS: Parent ratings of behavioral symptoms and adaptive functioning were within normative expectation, although rates of clinical impairment in adaptive functioning exceeded expected rates. A combination of familial/demographic and diagnostic variables were associated with acute functioning. In multiple regressions, tumor size best predicted adaptive functioning after initial diagnosis, whereas tumor location best predicted variance in behavioral symptoms. CONCLUSIONS: Children may be more vulnerable to acute impairment in adaptive functioning following diagnosis of a pediatric brain tumor, but rates of behavioral symptoms were within expectation. Familial, sociodemographic, and diagnostic variables may help to identify those most at risk of impairment. Screening of these factors within tertiary care settings will be useful to identify those most in need of psychosocial care during the initial phases of treatment.

Executive functions, social information processing, and social adjustment in young children born with very low birth weight.

Children born with very low birth weight (VLBW) are at risk for neurocognitive and behavioral sequelae. Although VLBW infants are at higher risk for deficits in executive functions (EFs) and social functioning during school-age years, few studies have investigated those sequelae or their association in young children born VLBW. We examined the associations between EFs and social functioning in preterm, VLBW children age 4-6 years (n = 20) and matched, term-born, normal birth weight controls admitted to the neonatal intensive care unit (NICU) after birth (n = 18). The groups did not differ significantly on measures of EFs, social information processing, or parent-reported social adjustment. The VLBW group had lower IQs than controls, though both group means were in the average range. Within the VLBW group, medical predictors of better EFs included older gestational age at birth and no history of bronchopulmonary dysplasia. Across groups, EFs and social information processing were positively correlated. Deficits in EFs and social functioning may emerge after the preschool years in VLBW children, or improved care of children born VLBW may be reducing the cognitive and psychosocial sequelae observed in earlier cohorts. Among children born VLBW, early EFs may be directly related to social information processing.

Spiritual coping predicts 5-year health outcomes in adolescents with cystic fibrosis.

BACKGROUND: Positive spiritual coping in adolescent patients with cystic fibrosis (CF) is associated with better emotional functioning, but its role in health outcomes is unknown. METHODS: Adolescents diagnosed with CF (n = 46; M = 14.7 years) reported on their use of positive and negative spiritual coping. Measures of nutrition status (BMIp), pulmonary function (%FEV1), and hospitalizations were obtained for a five-year follow up period. Changes in BMIp and %FEV1 scores were estimated with hierarchical linear models; days hospitalized were modeled with negative binomial regression. RESULTS: Positive spiritual coping was associated with slower decline in pulmonary function, stable vs. declining nutritional status, and fewer days hospitalized over the five-year period. Negative spiritual coping was associated with higher BMI percentile at baseline, but not with health outcomes over time. CONCLUSIONS: These results suggest that positive spiritual coping plays a key role in maintaining long-term health of adolescent patients with CF.

Executive functions and social skills in survivors of pediatric brain tumor.

Medical advances have resulted in increased survival rates for children with brain tumors. Consequently, issues related to survivorship have become more critical. The use of multimodal treatment, in particular cranial radiation therapy, has been associated with subsequent cognitive decline. Specifically, deficits in executive functions have been reported in survivors of various types of pediatric brain tumor. Survivors are left with difficulties, particularly in self-monitoring, initiation, inhibition, and planning, to name a few. Another domain in which survivors of pediatric brain tumor have been reported to show difficulty is that of social skills. Parents, teachers, and survivors themselves have reported decreased social functioning following treatment. Deficits in executive functions and social skills are likely interrelated in this population, as executive skills are needed to navigate various aspects of social interaction; however, this has yet to be studied empirically. Twenty-four survivors of pediatric brain tumor were assessed using a computerized task of executive functions, as well as paper-and-pencil measures of social skills and real-world executive skills. Social functioning was related to a specific aspect of executive functions, that is, the survivors' variability in response time, such that inconsistent responding was associated with better parent-reported and survivor-reported social skills, independent of intellectual abilities. Additionally, parent-reported real-world global executive abilities predicted parent-reported social skills. The implications of these findings for social skills interventions and future research are discussed.

An fMRI investigation of working memory and its relationship with cardiorespiratory fitness in pediatric posterior fossa tumor survivors who received cranial radiation therapy.

BACKGROUND: The present study investigated the relationship between cardiorespiratory fitness and executive functioning in pediatric brain tumor survivors who received cranial radiation. This population is known to show executive dysfunction and lower rates of aerobic exercise compared to peers. PROCEDURE: Nine adolescent survivors of pediatric posterior fossa tumor completed an n-back working memory task during a functional MRI scan, as well as cardiorespiratory fitness testing on a cycle ergometer. RESULTS: Neuroimaging findings indicated typical activation patterns associated with working memory, mainly in the frontal-parietal network. Higher cardiorespiratory fitness was related to better performance on a behavioral measure of working memory and more efficient neural functioning. CONCLUSIONS: This study provides preliminary evidence that cardiorespiratory fitness may be related to executive functioning, particularly working memory, in pediatric brain tumor survivors. Descriptions of the brain regions recruited for working memory by pediatric brain tumor survivors may be used to inform future interventions or indicators of treatment efficacy.

Cardiorespiratory fitness in survivors of pediatric posterior fossa tumor.

Advances in medical therapies have greatly improved survivorship rates in children diagnosed with brain tumor; as a result, morbidities associated with survivorship have become increasingly important to identify and address. In general, pediatric posterior fossa tumor survivors tend to be less physically active than peers. This may be related to late effects of diagnosis and treatment, including cardiovascular, endocrine, psychological, and neurocognitive difficulties. Exercise has been shown to be effective in improving physical functioning, mood, and even cognitive functioning. Consequently, the benefits of physical exercise need to be explored and incorporated into the daily lives of pediatric posterior fossa tumor survivors. The primary aim of the present study was to establish the feasibility and safety of cardiorespiratory fitness testing in pediatric posterior fossa tumor survivors who had received cranial radiation therapy. In addition, comparing our cohort with previously published data, we found that pediatric posterior fossa tumor survivors tended to be less fit than children with pulmonary disease and healthy controls and approximately as fit as children with chronic heart disease and survivors of other types of childhood cancer. The importance of cardiorespiratory fitness in pediatric posterior fossa tumor survivors is discussed along with implications for future directions.

Executive dysfunction in pediatric posterior fossa tumor survivors: a systematic literature review of neurocognitive deficits and interventions.

Improved medical therapies have increased survivorship rates for children with posterior fossa tumors; resultantly, morbidities associated with survivorship, such as executive function deficits, have become increasingly important to identify and address. Executive dysfunction can impact academic achievement as well as functional outcomes. We summarize studies describing executive functioning deficits in pediatric posterior fossa tumor survivors who received cranial radiation therapy and intervention studies that have targeted executive functioning deficits. Previous theoretical models describing the etiology of these deficits are reviewed, and a new, more comprehensive model is proposed. Future research should move toward incorporating neuroimaging, longitudinal designs, and multiple informants.

Cellular antioxidant activity of common fruits.

Measurement of antioxidant activity using biologically relevant assays is important in the screening of fruits for potential health benefits. The cellular antioxidant activity (CAA) assay quantifies antioxidant activity in cell culture and was developed to meet the need for a more biologically representative method than the popular chemistry antioxidant capacity measures. The objective of the study was to determine the cellular antioxidant activity, total phenolic contents, and oxygen radical absorbance capacity (ORAC) values of 25 fruits commonly consumed in the United States. Pomegranate and berries (wild blueberry, blackberry, raspberry, and blueberry) had the highest CAA values, whereas banana and melons had the lowest. Apples were found to be the largest contributors of fruit phenolics to the American diet, and apple and strawberries were the biggest suppliers of cellular antioxidant activity. Increasing fruit consumption is a logical strategy to increase antioxidant intake and decrease oxidative stress and may lead to reduced risk of cancer.

Structure-activity relationships of flavonoids in the cellular antioxidant activity assay.

Chemical antioxidant activity assays are used extensively to evaluate the potential bioactivity of plant foods and their phytochemical constituents, but they do not mimic the complexity of biological systems. The cellular antioxidant activity (CAA) activity assay was developed to be a more biologically relevant model to measure antioxidant activity. Structure-activity relationships of flavonoids have been determined in many chemistry antioxidant activity assays, and they vary with the protocols. The objective of this study was to determine structure-activity relationships of selected flavonoids in the CAA assay. The structures that conferred flavonoids with the most antioxidant activity in the CAA assay were a 3',4'- o-dihydroxyl group in the B-ring, a 2,3-double bond combined with a 4-keto group in the C-ring, and a 3-hydroxyl group. Isoflavones had no cellular antioxidant activity. Flavanols with a galloyl moiety had higher antioxidant activity than those without, and a B-ring 3',4',5'-trihydroxyl group further improved their efficacy. ORAC values for flavonoids were not related to their CAA values. Knowledge of structure-activity relationships in the CAA assay may be helpful in assessing potential in vivo antioxidant activity of flavonoids.

Cellular antioxidant activity (CAA) assay for assessing antioxidants, foods, and dietary supplements.

A cellular antioxidant activity (CAA) assay for quantifying the antioxidant activity of phytochemicals, food extracts, and dietary supplements has been developed. Dichlorofluorescin is a probe that is trapped within cells and is easily oxidized to fluorescent dichlorofluorescein (DCF). The method measures the ability of compounds to prevent the formation of DCF by 2,2'-azobis(2-amidinopropane) dihydrochloride (ABAP)-generated peroxyl radicals in human hepatocarcinoma HepG2 cells. The decrease in cellular fluorescence when compared to the control cells indicates the antioxidant capacity of the compounds. The antioxidant activities of selected phytochemicals and fruit extracts were evaluated using the CAA assay, and the results were expressed in micromoles of quercetin equivalents per 100 micromol of phytochemical or micromoles of quercetin equivalents per 100 g of fresh fruit. Quercetin had the highest CAA value, followed by kaempferol, epigallocatechin gallate (EGCG), myricetin, and luteolin among the pure compounds tested. Among the selected fruits tested, blueberry had the highest CAA value, followed by cranberry > apple = red grape > green grape. The CAA assay is a more biologically relevant method than the popular chemistry antioxidant activity assays because it accounts for some aspects of uptake, metabolism, and location of antioxidant compounds within cells.

Apple peels as a value-added food ingredient.

There is some evidence that chronic diseases, such as cancer and cardiovascular disease, may occur as a result of oxidative stress. Apple peels have high concentrations of phenolic compounds and may assist in the prevention of chronic diseases. Millions of pounds of waste apple peels are generated in the production of applesauce and canned apples in New York State each year. We proposed that a valuable food ingredient could be made using the peels of these apples if they could be dried and ground to a powder without large losses of phytochemicals. Rome Beauty apple peels were treated with citric acid dips, ascorbic acid dips, and blanches before being oven-dried at 60 degrees C. Only blanching treatments greatly preserved the phenolic compounds, and peels blanched for 10 s had the highest total phenolic content. Rome Beauty apple peels were then blanched for 10 s and dried under various conditions (oven-dried at 40, 60, or 80 degrees C, air-dried, or freeze-dried). The air-dried and freeze-dried apple peels had the highest total phenolic, flavonoid, and anthocyanin contents. On a fresh weight basis, the total phenolic and flavonoid contents of these samples were similar to those of the fresh apple peels. Freeze-dried peels had a lower water activity than air-dried peels on a fresh weight basis. The optimal processing conditions for the ingredient were blanching for 10s and freeze-drying. The process was scaled up, and the apple peel powder ingredient was characterized. The total phenolic content was 3342 +/- 12 mg gallic acid equivalents/100 g dried peels, the flavonoid content was 2299 +/- 52 mg catechin equivalents/100 g dried peels, and the anthocyanin content was 169.7 +/- 1.6 mg cyanidin 3-glucoside equivalents/100 g dried peels. These phytochemical contents were a significantly higher than those of the fresh apple peels if calculated on a fresh weight basis (p < 0.05). The apple peel powder had a total antioxidant activity of 1251 +/- 56 micromol vitamin C equivalents/g, similar to fresh Rome Beauty peels on a fresh weight basis (p > 0.05). One gram of powder had an antioxidant activity equivalent to 220 mg of vitamin C. The freeze-dried apple peels also had a strong antiproliferative effect on HepG(2) liver cancer cells with a median effective dose (EC(50)) of 1.88 +/- 0.01 mg/mL. This was lower than the EC(50) exhibited by the fresh apple peels (p < 0.05). Apple peel powder may be used in a various food products to add phytochemicals and promote good health.

Antioxidant activity of apple peels.

Consumption of fruits and vegetables has been shown to be effective in the prevention of chronic diseases. These benefits are often attributed to the high antioxidant content of some plant foods. Apples are commonly eaten and are large contributors of phenolic compounds in European and North American diets. The peels of apples, in particular, are high in phenolics. During applesauce and canned apple manufacture, the antioxidant-rich peels of apples are discarded. To determine if a useful source of antioxidants is being wasted, the phytochemical content, antioxidant activity, and antiproliferative activity of the peels of four varieties of apples (Rome Beauty, Idared, Cortland, and Golden Delicious) commonly used in applesauce production in New York state were investigated. The values of the peels were compared to those of the flesh and flesh + peel components of the apples. Within each variety, the total phenolic and flavonoid contents were highest in the peels, followed by the flesh + peel and the flesh. Idared and Rome Beauty apple peels had the highest total phenolic contents (588.9 +/- 83.2 and 500.2 +/- 13.7 mg of gallic acid equivalents/100 g of peels, respectively). Rome Beauty and Idared peels were also highest in flavonoids (306.1 +/- 6.7 and 303.2 +/- 41.5 mg of catechin equivalents/100 g of peels, respectively). Of the four varieties, Idared apple peels had the most anthocyanins, with 26.8 +/- 6.5 mg of cyanidin 3-glucoside equivalents/100 g of peels. The peels all had significantly higher total antioxidant activities than the flesh + peel and flesh of the apple varieties examined. Idared peels had the greatest antioxidant activity (312.2 +/- 9.8 micromol of vitamin C equivalents/g of peels). Apple peels were also shown to more effectively inhibit the growth of HepG(2) human liver cancer cells than the other apple components. Rome Beauty apple peels showed the most bioactivity, inhibiting cell proliferation by 50% at the low concentration of 12.4 +/- 0.4 mg of peels/mL. The high content of phenolic compounds, antioxidant activity, and antiproliferative activity of apple peels indicate that they may impart health benefits when consumed and should be regarded as a valuable source of antioxidants.