R01MD015974

Pathophysiologic Mechanisms Leading to Intrahepatic Fat Accumulation in Obese Youth - Project Summary

Nonalcoholic fatty liver disease (NAFLD) is the most common hepatic disease in pediatrics, affecting about 30% of obese youth. The term NAFLD defines a wide spectrum of disease severity ranging from simple intrahepatic fat accumulation without liver injury (steatosis) to nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis. A 20-year retrospective study has shown that subjects who develop NAFLD during their youth have about 13 times higher mortality rate for end-stage liver disease than healthy subjects of similar age and gender.

NAFLD is highly prevalent among Hispanic youth, while non-Hispanic Black (NHB) youth are protected against intrahepatic fat accumulation even in the presence of severe obesity and insulin resistance. Understanding the pathophysiology underlying these differences could shed new light on the mechanisms leading to NAFLD in obese youth.

Our preliminary data suggest that Hispanic and NHB obese youth might have a different ability to metabolize carbohydrates (CHO) through glycolysis, with Hispanics showing higher glycolysis than NHB. Therefore, Hispanics might experience a higher rate of tricarboxylic acid cycle (TCA) and hepatic de novo lipogenesis (DNL). In the present study, we aim to address the following questions:

1) Is the different susceptibility between Hispanics and NHB in developing NAFLD due to a higher capability of Hispanics to metabolize CHO through glycolysis, TCA cycle, and DNL?
2) Do these metabolic changes anticipate the onset of the disease in Hispanic youth?
3) Are the higher rates of glycolysis, TCA, and DNL driven by high but non-pathologic changes in glucose levels over time?

To address our aims, we plan to recruit 30 Hispanics and 30 NHB obese youth and to measure glycolysis by using a new method to assess lactate kinetics and to determine the TCA cycle and DNL by using 13C-propionate and D2O. Moreover, we will assess glycolysis and intrahepatic fat content in a group of 150 Hispanic obese youth without fatty liver at baseline every 12 months for two years to determine whether higher glycolytic rates precede intrahepatic fat accumulation.

To assess whether metabolic changes in glycolysis are driven by higher but non-pathologic glucose levels, we will measure glucose changes over ten days every six months by using a continuous glucose monitoring system. If successful, these studies will provide novel insight into the pathogenesis of pediatric NAFLD and will open new avenues to test novel therapeutic approaches.

Yale Univ

TO SUPPORT BASIC, CLINICAL, SOCIAL, AND BEHAVIORAL RESEARCH, PROMOTE RESEARCH INFRASTRUCTURE AND TRAINING, FOSTER EMERGING PROGRAMS, DISSEMINATE INFORMATION, AND REACH OUT TO MINORITY AND OTHER HEALTH DISPARITY COMMUNITIES. THE NATIONAL INSTITUTE ON MINORITY HEALTH AND HEALTH DISPARITIES (NIMHD) HAS ESTABLISHED PROGRAMS TO PURSUE THESE GOALS: (1) THE CENTERS OF EXCELLENCE PROGRAM PROMOTES RESEARCH TO IMPROVE MINORITY HEALTH AND/OR REDUCE AND ELIMINATE HEALTH DISPARITIES, BUILDS RESEARCH CAPACITY FOR MINORITY HEALTH AND HEALTH DISPARITIES RESEARCH IN ACADEMIC INSTITUTIONS, ENCOURAGES PARTICIPATION OF HEALTH DISPARITY GROUPS AND COMMUNITIES IN BIOMEDICAL AND BEHAVIORAL RESEARCH AND PREVENTION AND INTERVENTION ACTIVITIES, AND BRINGS TOGETHER INVESTIGATORS FROM RELEVANT DISCIPLINES IN A MANNER THAT WILL ENHANCE AND EXTEND THE EFFECTIVENESS OF THEIR RESEARCH, (2) NIMHD RESEARCH ENDOWMENT PROGRAM BUILDS RESEARCH CAPACITY AND INFRASTRUCTURE AT ELIGIBLE NIMHD CENTERS OF EXCELLENCE OR ELIGIBLE SECTION 736 HEALTH PROFESSIONS SCHOOLS (42 U.S.C. 293) TO FACILITATE MINORITY HEALTH AND OTHER HEALTH DISPARITIES RESEARCH TO CLOSE THE DISPARITY GAP IN THE BURDEN OF ILLNESS AND DEATH EXPERIENCED BY RACIAL AND ETHNIC MINORITY AMERICANS AND OTHER HEALTH DISPARITY POPULATIONS, PROMOTES A DIVERSE AND STRONG SCIENTIFIC, TECHNOLOGICAL AND ENGINEERING WORKFORCE, AND EMPHASIZES THE RECRUITMENT AND RETENTION OF UNDERREPRESENTED MINORITIES AND OTHER SOCIO-ECONOMICALLY DISADVANTAGED POPULATIONS IN THE FIELDS OF BIOMEDICAL AND BEHAVIORAL RESEARCH AND OTHER AREAS OF THE SCIENTIFIC WORKFORCE, (3) THE CENTERS OF EXCELLENCE ON ENVIRONMENTAL HEALTH DISPARITIES RESEARCH TO STIMULATE BASIC AND APPLIED RESEARCH ON ENVIRONMENTAL HEALTH DISPARITIES, (4) MINORITY HEALTH AND HEALTH DISPARITIES INTERNATIONAL RESEARCH TRAINING PROGRAM (MHIRT) AWARDS ENABLE U.S. INSTITUTIONS TO TAILOR SHORT-TERM BASIC SCIENCE, BIOMEDICAL AND BEHAVIORAL MENTORED STUDENT INTERNATIONAL RESEARCH TRAINING OPPORTUNITIES TO ADDRESS GLOBAL ISSUES RELATED TO UNDERSTANDING, REDUCING, AND ELIMINATING HEALTH DISPARITIES, (5) SMALL BUSINESS INNOVATION RESEARCH (SBIR) PROGRAM INCREASES PRIVATE SECTOR COMMERCIALIZATION OF INNOVATIONS DERIVED FROM FEDERAL RESEARCH AND DEVELOPMENT, ENCOURAGES SMALL BUSINESS PARTICIPATION IN FEDERAL RESEARCH AND DEVELOPMENT, AND FOSTERS AND ENCOURAGES PARTICIPATION OF SOCIALLY AND ECONOMICALLY DISADVANTAGED SMALL BUSINESS CONCERNS AND WOMEN-OWNED SMALL BUSINESS CONCERNS IN TECHNOLOGICAL INNOVATION, (6) SMALL BUSINESS TECHNOLOGY TRANSFER (STTR) PROGRAM STIMULATES AND FOSTERS SCIENTIFIC AND TECHNOLOGICAL INNOVATION THROUGH COOPERATIVE RESEARCH DEVELOPMENT CARRIED OUT BETWEEN SMALL BUSINESS CONCERNS AND RESEARCH INSTITUTIONS, FOSTERS TECHNOLOGY TRANSFER BETWEEN SMALL BUSINESS CONCERNS AND RESEARCH INSTITUTIONS, INCREASES PRIVATE SECTOR COMMERCIALIZATION OF INNOVATIONS DERIVED FROM FEDERAL RESEARCH AND DEVELOPMENT, AND FOSTERS AND ENCOURAGES PARTICIPATION OF SOCIALLY AND ECONOMICALLY DISADVANTAGED SMALL BUSINESS CONCERNS AND WOMEN-OWNED SMALL BUSINESS CONCERNS IN TECHNOLOGICAL INNOVATION, (7) HEALTH DISPARITIES RESEARCH PROJECT GRANTS (RPG) SUPPORT INNOVATIVE PROJECTS TO ENHANCE OUR UNDERSTANDING OF BIOLOGICAL MECHANISMS, SOCIAL, BEHAVIORAL, AND HEALTH SERVICES THAT CAN DIRECTLY AND DEMONSTRABLY CONTRIBUTE TO THE IMPROVEMENT IN MINORITY HEALTH AND THE ELIMINATION OF HEALTH DISPARITIES WHICH INCLUDES THE (8) RESEARCH CENTERS IN MINORITY INSTITUTIONS (RCMI) BUILD CAPACITY FOR BASIC BIOMEDICAL AND/OR BEHAVIORAL RESEARCH, CLINICAL AND TRANSLATIONAL RESEARCH (RCTR) AND A NETWORK (RCTN) BY FOCUSING ON INSTITUTIONAL RESOURCE DEVELOPMENT, SUCH AS SUPPORTING CORE RESEARCH FACILITIES AND STAFF, PURCHASING ADVANCED INSTRUMENTATION, AND LABORATORY RENOVATIONS/ALTERATIONS (9) CLINICAL RESEARCH EDUCATION AND CAREER DEVELOPMENT (CRECD) AWARDS PROVIDE DIDACTIC TRAINING AND MENTORED CLINICAL RESEARCH EXPERIENCES TO DEVELOP INDEPENDENT RESEARCHERS WHO CAN LEAD CLINICAL RESEARCH STUDIES, ESPECIALLY THOSE ADDRESSING HEALTH DISPARITIES, (10) PATHWAY TO INDEPENDENCE AWARDS (K99/R00) TO INCREASE AND MAINTAIN A STRONG COHORT OF NEW AND TALENTED, NIH-SUPPORTED, INDEPENDENT INVESTIGATORS. (11) NIH RESEARCH CONFERENCE GRANT AND NIH RESEARCH CONFERENCE COOPERATIVE AGREEMENT PROGRAMS SUPPORT HIGH-QUALITY CONFERENCES THAT ARE RELEVANT TO THE MINORITY HEALTH AND HEALTH DISPARITIES, (12) TRANSDISCIPLINARY COLLABORATIVE CENTERS FOR HEALTH DISPARITIES RESEARCH COMPRISE REGIONAL COALITIONS OF ACADEMIC INSTITUTIONS, COMMUNITY ORGANIZATIONS, SERVICE PROVIDERS AND SYSTEMS, GOVERNMENT AGENCIES AND OTHER STAKEHOLDERS CONDUCTING COORDINATED RESEARCH, IMPLEMENTATION AND DISSEMINATION ACTIVITIES THAT TRANSCEND CUSTOMARY APPROACHES AND SILO ORGANIZATIONAL STRUCTURES TO ADDRESS CRITICAL QUESTIONS AT MULTIPLE LEVELS IN INNOVATIVE WAYS FOCUSED ON PRIORITY RESEARCH AREAS IN MINORITY HEALTH AND HEALTH DISPARITIES, (13) RUTH L. KIRSCHSTEIN NRSA INDIVIDUAL PREDOCTORAL FELLOWSHIP

93.307 - Minority Health and Health Disparities Research

National Institute for Minority Health and Health Disparities (NIMHD) [HHS - NIH]

Connecticut United States

State-Wide

Mechanisms of Disparities in Chronic Liver Diseases and Cancer (R01- Clinical Trial Not Allowed) (PAR-20-088)

Amendment Since initial award the total obligations have increased 387% from $668,756 to $3,257,727.