The Study of the Epidemiology of Pediatric Hypertension Registry (SUPERHERO): Rationale and Methods.

Despite increasing prevalence of hypertension in youth and high adult cardiovascular mortality rates, the long-term consequences of youth-onset hypertension remain unknown. This is due to limitations of prior research such as small sample sizes, reliance on manual record review, and limited analytic methods that did not address major biases. The Study of the Epidemiology of Pediatric Hypertension (SUPERHERO) is a multisite retrospective Registry of youth evaluated by subspecialists for hypertension disorders. Sites obtain harmonized electronic health record data using standardized biomedical informatics scripts validated with randomized manual record review. Inclusion criteria are index visit for International Classification of Diseases Diagnostic Codes, 10th Revision (ICD-10 code)-defined hypertension disorder ≥January 1, 2015 and age <19 years. We exclude patients with ICD-10 code-defined pregnancy, kidney failure on dialysis, or kidney transplantation. Data include demographics, anthropomorphics, U.S. Census Bureau tract, histories, blood pressure, ICD-10 codes, medications, laboratory and imaging results, and ambulatory blood pressure. SUPERHERO leverages expertise in epidemiology, statistics, clinical care, and biomedical informatics to create the largest and most diverse registry of youth with newly diagnosed hypertension disorders. SUPERHERO's goals are to (i) reduce CVD burden across the life course and (ii) establish gold-standard biomedical informatics methods for youth with hypertension disorders.

Social Risk Factors Influence Pediatric Emergency Department Utilization and Hospitalizations.

OBJECTIVE: To characterize the association of children's social risk factors with total number of emergency department (ED) visits or hospitalization and time to first subsequent ED or hospitalization. STUDY DESIGN: This was a retrospective cohort study of patients seen at a general pediatric clinic between 2017 and 2021 with documented ≥1 social risk factors screened per visit. Negative binomial or Poisson regression modeled ED utilization and hospitalizations as functions of the total number of risk factors or each unique risk factor. Time-varying Cox models were used to evaluate differences between those who screened positive and those who screened negative, controlling for demographic and clinical covariates. RESULTS: Overall, 4674 patients (mean age, 6.6 years; 49% female; 64% Hispanic; 21% Black) were evaluated across a total of 20 927 visits. Children with risk factors had higher rates of attention-deficit hyperactivity disorder, failure to gain weight, asthma, and prematurity compared with children with no risk (all P < .01). Adjusted models show a positive association between increased total number of factors and ED utilization (incidence rate ratio [IRR], 1.18; 95% CI, 1.12-1.23) and hospitalizations (IRR, 1.36; 95% CI, 1.26-1.47). There were no associations between a positive screen and time to first ED visit (hazard ratio [HR], 0.95; 95% CI, 0.85-1.06; P = .36) or hospitalization (HR, 1.15; 95% CI, 0.84-1.59; P = .40). CONCLUSIONS: Social risk factors were associated with increased ED utilization and hospitalizations at the patient level but were not significantly associated with time to subsequent acute care use. Future research should evaluate the effect of focused interventions on health care utilization, such as those addressing food insecurity and transportation challenges.

Screening for Problematic Sleep in a Diverse Sample of Infants.

OBJECTIVE: To examine screening strategies for identifying problematic sleep in a diverse sample of infants. METHODS: Parents of infants (5-19 months; N = 3,271) presenting for a primary care visit responded to five screening items and the Infant Sleep Questionnaire (ISQ), a validated measure of problematic infant sleep. If parents responded affirmatively to any screening item, primary care providers received a prompt to evaluate. For each of the screening questions, we examined differences in item endorsement and criterion related validity with the ISQ. Using conceptual composites of night waking and sleep difficulty, prevalence, criterion-related validity, and concurrent demographic correlates were analyzed. RESULTS: Infants were primarily of Black race (50.1%) or Hispanic ethnicity (31.7%), with the majority (63.3%) living in economically distressed communities. Rates of problematic sleep ranged from 7.4%, for a single item assessing parental perception of an infant having a sleep problem, to 74.0%, for a single item assessing night wakings requiring adult intervention. Items assessing sleep difficulty had high (95.0-97.8%) agreement with the ISQ in identifying infants without problematic sleep, but low agreement (24.9-34.0%) in identifying those with problematic sleep. The opposite was true for items assessing night waking, which identified 91.0-94.6% of those with sleep problems but only 31.8-46.9% of those without. CONCLUSIONS: Screening strategies for identifying problematic infant sleep yielded highly variable prevalence rates and associated factors, depending on whether the strategy emphasized parent-perceived sleep difficulty or night wakings. The strategy that is most appropriate will depend on the system's goals.

How can healthcare professionals provide guidance and support to parents of adolescents? Results from a primary care-based study.

BACKGROUND: This study explored the rewards and difficulties of raising an adolescent and investigated parents' level of interest in receiving guidance from healthcare providers on parenting and adolescent health topics. Additionally, this study investigated whether parents were interested in parenting programs in primary care and explored methods in which parents want to receive guidance. METHODS: Parents of adolescents (ages 12-18) who attended an outpatient pediatric clinic with their adolescent were contacted by telephone and completed a short telephone survey. Parents were asked open-ended questions regarding the rewards and difficulties of parenting and rated how important it was to receive guidance from a healthcare provider on certain parenting and health topics. Additionally, parents reported their level of interest in a parenting program in primary care and rated how they would like to receive guidance. RESULTS: Our final sample included 104 parents, 87% of whom were interested in a parenting program within primary care. A variety of parenting rewards and difficulties were associated with raising an adolescent. From the list of parenting topics, communication was rated very important to receive guidance on (65%), followed by conflict management (50%). Of health topics, parents were primarily interested in receiving guidance on sex (77%), mental health (75%), and alcohol and drugs (74%). Parents in the study wanted to receive guidance from a pediatrician or through written literature. CONCLUSIONS: The current study finds that parents identify several rewarding and difficult aspects associated with raising an adolescent and are open to receiving guidance on a range of parenting topics in a variety of formats through primary care settings. Incorporating such education into healthcare visits could improve parents' knowledge. Healthcare providers are encouraged to consider how best to provide parenting support during this important developmental time period.

Impact of socioeconomic markers on parents' retention of pediatric oncology home care education: A pilot study.

Little is known about the extent to which parents retain the education on how to manage home medical emergencies. We sought to describe retention of pediatric oncology home care education (POHCE) in a cohort of 24 parents of newly diagnosed children with cancer and investigate sociodemographic disparities in this retention. We measured retention using a vignette-based survey instrument. The mean score was 4 (range 0-6, SD = 1.6) and parents with high school only education and those with limited cancer health literacy scored lowest (2.5 and 2.8, respectively). Future POHCE interventions can focus on parents' literacy and education levels as predictors to tailor alternative education strategies.

Characteristics Associated with Confidential Consultation for Adolescents in Primary Care.

OBJECTIVE: To examine how provider report of confidential consultation in the electronic health record is associated with adolescent characteristics, health risk factors, and provider training. STUDY DESIGN: This prospective cohort study was conducted as part of a larger study implementing computerized clinical decision support in 2 urban primary care clinics. Adolescents used tablets to complete screening questions for specified risk factors in the waiting room. Adolescent-reported risk factors included sexual activity, substance use, and depressive symptoms. Providers were prompted on encounter forms to address identified risk factors and indicate whether confidential consultation was provided. Provider types included adolescent medicine board certified pediatrics and general pediatrics. Differences in proportions of adolescents reporting risk factors by provider type were assessed using χ2 tests. Associations between adolescent characteristics, risk factors, and provider-reported confidential consultation were examined using logistic regression analyses. RESULTS: The sample included 1233 English and Spanish-speaking adolescents 12-20 years of age (52% female; 60% black; 50% early adolescent). Patients seen by adolescent medicine board certified providers reported sexual activity, depressive symptoms, and substance use significantly more often than those seen by general pediatric providers. Among patients seen by board certified adolescent medicine providers, confidential consultation was provided to 90%. For those seen by general pediatric providers, confidential consultation was provided to 53%. Results of multiple logistic regression demonstrated that female sex, later adolescence, and clinic location were significantly associated with confidential consultation. CONCLUSIONS: Provider training is needed to reinforce the importance of confidential consultation for all adolescents.

Prevalence of pain reports in pediatric primary care and association with demographics, body mass index, and exam findings: a cross-sectional study.

BACKGROUND: Pediatric pain is associated to patient weight and demographics in specialized settings, but pain prevalence and its associated patient attributes in general pediatric outpatient care are unknown. Our objective was to determine the rate of positive pain screenings in pediatric primary care and evaluate the relationship between reported pain and obesity, demographics, and exam findings during routine pediatric encounters. METHODS: Cross-sectional observational study of 26,180 patients ages 2 to 19 seen in five urban pediatric primary care clinics between 2009 and 2016. Data were collected from systematic screening using a computerized clinical decision support system. Multivariable logistic regressions were used to analyze the association between pain reporting and obesity (body mass index), age, sex, race, season, insurance status, clinic site, prior pain reporting, pain reporting method, and exam findings. RESULTS: Pain was reported by the patient or caregiver in 14.9% of visits. In adjusted models, pain reporting was associated with obesity (Odds Ratio (OR) 1.23, 95% Confidence Intervals (CI) 1.11-1.35) and severe obesity (OR 1.32, CI 1.17-1.49); adolescents (OR 1.47, CI 1.33-1.61); and females (OR 1.21, CI 1.12-1.29). Pain reported at the preceding visit increased odds of pain reporting 2.67 times (CI 2.42-2.95). Abnormal abdominal, extremity, ear, nose, throat, and lymph node exams were associated with pain reporting. Pain reporting increased in minority races within clinics that predominantly saw a concordant race. CONCLUSIONS: Pain is common in general pediatric encounters, and occurs more frequently in obese children and those who previously reported pain. Pain reporting may be influenced by seasonal variation and clinic factors. Future pediatric pain screening may be guided by associated risk factors to improve identification and targeted healthcare interventions.

Health care providers' perceptions of use and influence of clinical decision support reminders: qualitative study following a randomized trial to improve HPV vaccination rates.

BACKGROUND: Human Papillomavirus (HPV) leads to serious health issues and remains the most common sexually transmitted infection. Despite availability of effective vaccines, HPV vaccination rates are suboptimal. Furthermore, providers recommend the HPV vaccine less than half the time for eligible patients. Prior informatics research has demonstrated the effectiveness of computer-based clinical decision support (CDS) in changing provider behavior, especially in the area of preventative services. METHODS: Following a randomized clinical trial to test the effect of a CDS intervention on HPV vaccination rates, we conducted semi-structured interviews with health care providers to understand whether they noticed the CDS reminders and why providers did or did not respond to the prompts. Eighteen providers, a mix of medical doctors and nurse practitioners, were interviewed from five publicly-funded, urban health clinics. Interview data were qualitatively analyzed by two independent researchers using inductive content analysis. RESULTS: While most providers recalled seeing the CDS reminders, few of them perceived the intervention as effective in changing their behavior. Providers stated many reasons for why they did not perceive a change in their behavior, yet the results of the trial showed HPV vaccination rates increased as a result of the intervention. CONCLUSIONS: CDS reminders may be effective at changing provider behavior even if providers perceive them to be of little use. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02551887 Registered on September 15, 2015.

Influence of Maternal Factors in Neonatologists' Counseling for Periviable Pregnancies.

Background Neonatologists have varying counseling practices for women with threatened periviable pregnancies. Previous research has suggested this variability may be influenced by social and economic factors of the mother. Objective The objective of this study was to determine the relative influence of maternal factors in counseling recommendations for periviable pregnancies. Methods A national cohort of neonatologists was sent a web-based survey. Five maternal characteristics were varied across eight vignettes: age, education, race, parity, and pregnancy "intendedness." Following each vignette, participants reported their likelihood to recommend full resuscitation versus comfort care. Conjoint analysis was used to assess the relative influence of each factor on respondents' recommendations. Results Responses from 328 neonatologists were included. Of the five tested maternal characteristics, parity and intendedness had the highest importance scores (40.2 and 35.0), followed by race, education, and age. If parents requested resuscitation, respondents were highly likely to comply with preferences, with little variation across vignettes. Conclusion Fetal-specific factors such as gestational age and estimated weight are known to influence counseling and decision making for extremely preterm infants. Our results suggest that maternal factors may also influence counseling practices, although physicians are likely to comply with parental preferences regardless of maternal factors. Future research should identify how maternal characteristics impact actual counseling practices.

Acetyl CoA carboxylase inactivation and meiotic maturation in mouse oocytes.

In mouse oocytes, meiotic induction by pharmacological activation of PRKA (adenosine monophosphate-activated protein kinase; formerly known as AMPK) or by hormones depends on stimulation of fatty acid oxidation (FAO). PRKA stimulates FAO by phosphorylating and inactivating acetyl CoA carboxylase (ACAC; formerly ACC), leading to decreased malonyl CoA levels and augmenting fatty-acid transport into mitochondria. We investigated a role for ACAC inactivation in meiotic resumption by testing the effect of two ACAC inhibitors, CP-640186 and Soraphen A, on mouse oocytes maintained in meiotic arrest in vitro. These inhibitors significantly stimulated the resumption of meiosis in arrested cumulus cell-enclosed oocytes, denuded oocytes, and follicle-enclosed oocytes. This stimulation was accompanied by an increase in FAO. Etomoxir, a malonyl CoA analogue, prevented meiotic resumption as well as the increase in FAO induced by ACAC inhibition. Citrate, an ACAC activator, and CBM-301106, an inhibitor of malonyl CoA decarboxylase, which converts malonyl CoA to acetyl CoA, suppressed both meiotic induction and FAO induced by follicle-stimulating hormone, presumably by maintaining elevated malonyl CoA levels. Mouse oocyte-cumulus cell complexes contain both isoforms of ACAC (ACACA and ACACB); when wild-type and Acacb(-/-) oocytes characteristics were compared, we found that these single-knockout oocytes showed a significantly higher FAO level and a reduced ability to maintain meiotic arrest, resulting in higher rates of germinal vesicle breakdown. Collectively, these data support the model that ACAC inactivation contributes to the maturation-promoting activity of PRKA through stimulation of FAO.

Nutrient pathways regulating the nuclear maturation of mammalian oocytes.

Oocyte maturation is defined as that phase of development whereby a fully grown oocyte reinitiates meiotic maturation, completes one meiotic division with extrusion of a polar body, then arrests at MII until fertilisation. Completion of maturation depends on many different factors, not the least of which is the proper provision of energy substrates to fuel the process. Interaction of the oocyte and somatic compartment of the follicle is critical and involves numerous signals exchanged between the two cell types in both directions. One of the prominent functions of the cumulus cells is the channelling of metabolites and nutrients to the oocyte to help stimulate germinal vesicle breakdown and direct development to MII. This entails the careful integration and coordination of numerous metabolic pathways, as well as oocyte paracrine signals that direct certain aspects of cumulus cell metabolism. These forces collaborate to produce a mature oocyte that, along with accompanying physiological changes called cytoplasmic maturation, which impart subsequent developmental competence to the oocyte, can be fertilised and develop to term. This review focuses on nuclear maturation and the metabolic interplay that regulates it, with special emphasis on data generated in the mouse.

Secondhand smoke exposure, parental depressive symptoms and preschool behavioral outcomes.

Little is known about the association of secondhand smoke (SHS) exposure and behavioral conditions among preschoolers. A cross-sectional analysis was used to examine billing and pharmacy claims from November 2004 to June 2012 linked to medical encounter-level data for 2,441 children from four pediatric community health clinics. Exposure to SHS was associated with attention deficit-hyperactivity disorder/ADHD and disruptive behavior disorder/DBD after adjusting for potential confounding factors. Assessment of exposure to SHS and parental depressive symptoms in early childhood may increase providers' ability to identify children at higher risk of behavioral issues and provide intervention at the earliest stages.

Medical legal partnership and health informatics impacting child health: Interprofessional innovations.

Dramatic differences in health are closely related to degrees of social and economic disadvantage. Poverty-induced hardships such as food insecurity, utility shut-offs, and substandard housing, all have the potential to negatively impact the health of families. In an effort to better address social determinants of health in pediatric primary health care settings using the Medical Legal Partnership (MLP) model of health care delivery, an interprofessional team of investigators came together to design an innovative process for using computerized clinical decision support to identify health-harming legal and social needs, improve the delivery of appropriate physician counseling, and streamline access to legal and social service professionals when non-medical remedies are required. This article describes the interprofessional nature of the MLP model itself, illustrates the work that was done to craft this innovative health informatics approach to implementing MLP, and demonstrates how pediatricians, social workers and attorneys may work together to improve child health outcomes.

Decision support from local data: creating adaptive order menus from past clinician behavior.

OBJECTIVE: Reducing care variability through guidelines has significantly benefited patients. Nonetheless, guideline-based Clinical Decision Support (CDS) systems are not widely implemented or used, are frequently out-of-date, and cannot address complex care for which guidelines do not exist. Here, we develop and evaluate a complementary approach - using Bayesian Network (BN) learning to generate adaptive, context-specific treatment menus based on local order-entry data. These menus can be used as a draft for expert review, in order to minimize development time for local decision support content. This is in keeping with the vision outlined in the US Health Information Technology Strategic Plan, which describes a healthcare system that learns from itself. MATERIALS AND METHODS: We used the Greedy Equivalence Search algorithm to learn four 50-node domain-specific BNs from 11,344 encounters: abdominal pain in the emergency department, inpatient pregnancy, hypertension in the Urgent Visit Clinic, and altered mental state in the intensive care unit. We developed a system to produce situation-specific, rank-ordered treatment menus from these networks. We evaluated this system with a hospital-simulation methodology and computed Area Under the Receiver-Operator Curve (AUC) and average menu position at time of selection. We also compared this system with a similar association-rule-mining approach. RESULTS: A short order menu on average contained the next order (weighted average length 3.91-5.83 items). Overall predictive ability was good: average AUC above 0.9 for 25% of order types and overall average AUC .714-.844 (depending on domain). However, AUC had high variance (.50-.99). Higher AUC correlated with tighter clusters and more connections in the graphs, indicating importance of appropriate contextual data. Comparison with an Association Rule Mining approach showed similar performance for only the most common orders with dramatic divergence as orders are less frequent. DISCUSSION AND CONCLUSION: This study demonstrates that local clinical knowledge can be extracted from treatment data for decision support. This approach is appealing because: it reflects local standards; it uses data already being captured; and it produces human-readable treatment-diagnosis networks that could be curated by a human expert to reduce workload in developing localized CDS content. The BN methodology captured transitive associations and co-varying relationships, which existing approaches do not. It also performs better as orders become less frequent and require more context. This system is a step forward in harnessing local, empirical data to enhance decision support.

Early cow's milk introduction is associated with failed personal-social milestones after 1 year of age.

UNLABELLED: Both the American Academy of Pediatrics (AAP) and the Institute of Medicine (IOM) recommend delaying the introduction of cow's milk until after 1 year of age due to its low absorbable iron content. We used a novel computerized decision support system to gather data from multiple general pediatrics offices. We asked families whether their child received cow's milk before 1 year of age, had a low-iron diet, or used low-iron formula. Then, at subsequent visits, we performed a modified developmental assessment using the Denver II. We assessed the effect of early cow's milk or a low-iron diet on the later failure of achieving developmental milestones. We controlled for covariates using logistic regression. Early cow's milk introduction (odds ratio (OR) 1.30, p = 0.012), as well as a low-iron diet or low-iron formula (OR 1.42, p < 0.001), was associated with increased rates of milestone failure. Only personal-social milestones (OR 1.44, p = 0.002) showed a significantly higher rate of milestone failure. Both personal-social (OR 1.42, p < 0.001) and language (OR 1.22, p = 0.009) showed higher rates of failure in children with a low-iron diet. CONCLUSIONS: There is an association between the introduction of cow's milk before 1 year of age and the rate of delayed developmental milestones after 1 year of age. This adds strength to the recommendations from the AAP and IOM to delay cow's milk introduction until after 1 year of age.

Perturbing microtubule integrity blocks AMP-activated protein kinase-induced meiotic resumption in cultured mouse oocytes.

The oocyte meiotic spindle is comprised of microtubules (MT) that bind chromatin and regulate both metaphase plate formation and karyokinesis during meiotic maturation; however, little information is known about their role in meiosis reinitiation. This study was conducted to determine if microtubule integrity is required for meiotic induction and to ascertain how it affects activation of AMP-activated protein kinase (AMPK), an important participant in the meiotic induction process. Treatment with microtubule-disrupting agents nocodazole and vinblastine suppressed meiotic resumption in a dose-dependent manner in both arrested cumulus cell-enclosed oocytes (CEO) stimulated with follicle-stimulating hormone (FSH) and arrested denuded oocytes (DO) stimulated with the AMPK activator, 5-aminoimidazole-4-carboxamide-1-beta-4-ribofuranoside (AICAR). This effect coincided with suppression of AMPK activation as determined by western blotting and germinal vesicle immunostaining. Treatment with the MT stabilizer paclitaxel also suppressed meiotic induction. Targeting actin filament polymerization had only a marginal effect on meiotic induction. Immunolocalization experiments revealed that active AMPK colocalized with γ-tubulin during metaphase I and II stages, while it localized at the spindle midzone during anaphase. This discrete localization pattern was dependent on MT integrity. Treatment with nocodazole led to disruption of proper spindle pole localization of active AMPK, while paclitaxel induced excessive polymerization of spindle MT and formation of ectopic asters with accentuated AMPK colocalization. Although stimulation of AMPK increased the rate of germinal vesicle breakdown (GVB), spindle formation and polar body (PB) extrusion, the kinase had no effect on peripheral movement of the spindle. These data suggest that the meiosis-inducing action and localization of AMPK are regulated by MT spindle integrity during mouse oocyte maturation.

The 'Product Environment' is an Important Driver of Health. It's Time to Measure It.

Through their products and services, businesses have a meaningful impact on their customers' health. When markets reward products that induce unhealthy behaviors, like poor diet and limited physical activity, they fuel the chronic disease epidemic. For market mechanisms to reward positive, and to punish negative, influences on healthy behaviors, companies' influences will need to be measured. Inspired by the technique of health impact assessment, we propose an approach to measuring these influences, based on examining usage patterns and the activities that result from a given product or service and then mapping those experiences to a core set of health behaviors.

Automated generation of comparator patients in the electronic medical record.

Background: Well-designed randomized trials provide high-quality clinical evidence but are not always feasible or ethical. In their absence, the electronic medical record (EMR) presents a platform to conduct comparative effectiveness research, central to the emerging academic learning health system (aLHS) model. A barrier to realizing this vision is the lack of a process to efficiently generate a reference comparison group for each patient. Objective: To test a multi-step process for the selection of comparators in the EMR. Materials and Methods: We conducted a mixed-methods study within a large aLHS in North Carolina. We (1) created a list of 35 candidate variables; (2) surveyed 270 researchers to assess the importance of candidate variables; and (3) built consensus rankings around survey-identified variables (ie, importance scores >7) across two panels of 7-8 clinical research experts. Prioritized algorithm inputs were collected from the EMR and applied using a greedy matching technique. Feasibility was measured as the percentage of patients with 100 matched comparators and performance was measured via computational time and Euclidean distance. Results: Nine variables were selected: age, sex, race, ethnicity, body mass index, insurance status, smoking status, Charlson Comorbidity Index, and neighborhood percentage in poverty. The final process successfully generated 100 matched comparators for each of 1.8 million candidate patients, executed in less than 100 min for the majority of strata, and had average Euclidean distance 0.043. Conclusion: EMR-derived matching is feasible to implement across a diverse patient population and can provide a reproducible, efficient source of comparator data for observational studies, with additional testing in clinical research applications needed.

Better Guidelines and Policies: AAP's Partnership for Policy Implementation.

OBJECTIVES: In 2005, the American Academy of Pediatrics founded the Partnership for Policy Implementation (PPI). The PPI has collaborated with authors to improve the quality of clinical guidelines, technical reports, and policies that standardize care delivery, improve care quality and patient outcomes, and reduce variation and costs. METHODS: In this article, we describe how the PPI trained informaticians apply a variety of tools and techniques to these guidance documents, eliminating ambiguity in clinical recommendations and allowing guideline recommendations to be implemented by practicing clinicians and electronic health record (EHR) developers more easily. RESULTS: Since its inception, the PPI has participated in the development of 45 published and 27 in-progress clinical practice guidelines, policy statements, technical and clinical reports, and other projects endorsed by the American Academy of Pediatrics. The partnership has trained informaticians to apply a variety of tools and techniques to eliminate ambiguity or lack of decidability and can be implemented by practicing clinicians and EHR developers. CONCLUSIONS: With the increasing use of EHRs in pediatrics, the need for medical societies to improve the clarity, decidability, and actionability of their guidelines has become more important than ever.

A requirement for fatty acid oxidation in the hormone-induced meiotic maturation of mouse oocytes.

We have previously shown that fatty acid oxidation (FAO) is required for AMP-activated protein kinase (PRKA)-induced maturation in vitro. In the present study, we have further investigated the role of this metabolic pathway in hormone-induced meiotic maturation. Incorporating an assay with (3)H-palmitic acid as the substrate, we first examined the effect of PRKA activators on FAO levels. There was a significant stimulation of FAO in cumulus cell-enclosed oocytes (CEO) treated with 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) and RSVA405. In denuded oocytes (DO), AICAR stimulated FAO only in the presence of carnitine, the molecule that facilitates fatty acyl CoA entry into the mitochondria. The carnitine palmitoyltransferase 1 activator C75 successfully stimulated FAO in CEO. All three of these activators trigger germinal vesicle breakdown. Meiotic resumption induced by follicle-stimulating hormone (FSH) or amphiregulin was completely inhibited by the FAO inhibitors etomoxir, mercaptoacetate, and malonyl CoA. Importantly, FAO was increased in CEO stimulated by FSH and epidermal growth factor, and this increase was blocked by FAO inhibitors. Moreover, compound C, a PRKA inhibitor, prevented the FSH-induced increase in FAO. Both carnitine and palmitic acid augmented hormonal induction of maturation. In a more physiological setting, etomoxir eliminated human chorionic gonadotropin (hCG)-induced maturation in follicle-enclosed oocytes. In addition, CEO and DO from hCG-treated mice displayed an etomoxir-sensitive increase in FAO, indicating that this pathway was stimulated during in vivo meiotic resumption. Taken together, our data indicate that hormone-induced maturation in mice requires a PRKA-dependent increase in FAO.