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This project is an extension of the work completed under the project entitled "Mechanisms of Phytochemical Elicitation with Acetate - a New Window into Inducible Biochemical Pathways" Justification: The project focuses on the evaluation of plant extracts that can be used for the prevention and treatment of metabolic syndrome and diabetes. These extracts were identified as biologically active as the result of a large screening program that occurred over 5 years and involving 4 academic institutions. These extracts will become a product of new use agriculture and provide local farmers with the opportunity to grow high value crops as an alternative to traditional crops that serve merely as a source of calories. Alternative agents for the prevention and treatment of metabolic syndrome and diabetes are in great demand as its prevalence has increased dramatically in recent years, leading to an epidemic increase in the incidence of diabetes in NJ and around the world. Therefore, the proposed research will have a significant impact on multiple goal areas of NJAES including competitive agriculture, public health, food safety and economic development. In addition, the recently established Center for Gastro-Intestinal Research (CGIR), a collaboration between Rutgers and the Dutch based research institute TNO, will provide NJAES with an unique research and educational opportunity. The lab is focused on the use of the TNO gastroIntestinal Model (TIM), a dynamic multi-compartmental, computer-controlled model that closely simulates all in vivo conditions of the upper gastrointestinal tract of humans. TIM can be used to study bioaccessibility and stability of botanical extracts, as well as many other pharmaceutical related applications. <P>
The overall objective of this project is to examine the role of selected bioactive extracts (and components) on insulin action in vivo and evaluate cellular mechanisms of action. <P>Specific Objective 1: To provide a comprehensive analysis of the hypothesis that extracts from Artemisia sp. and Rubus improves insulin sensitivity. <P>Specific Objective 2. To isolate and characterize the active components of the extracts through the activity-guided fractionation based on the in vitro activities in muscle cells and adipocytes. <P>Specific Objective 3. To assess the bioavailability of active components using TNO Intestinal Model (TIM) apparatus that simulates human gastro intestinal tract.
NON-TECHNICAL SUMMARY: The occurrence of type 2 diabetes continues to soar to epidemic proportions reaching almost 8% (23.6 million) of the population in the U.S. alone. Another 57 million Americans have prediabetes, defined by an impaired fasting glucose values as a result of insulin resistance. Insulin resistance is a key pathophysiologic feature of the "metabolic syndrome" and is strongly associated with co-existing cardiovascular risk factors and accelerated atherosclerosis. Due to the clinical consequences associated with insulin resistance in subjects with metabolic syndrome and type 2 diabetes, clinical regimens directed at increasing insulin sensitivity in vivo remain one of the most desirable goals of treatment. Although it is well established that lifestyle modification can improve insulin resistance and effectively improve many of the risk factors associated with metabolic syndrome, the success of maintaining lifestyle changes in humans over a chronic period is poor. Therefore, strategies to improve insulin resistance by pharmacological means have represented the traditional approach for clinical medicine. However, because of the widespread use of dietary supplements by the general public, nutritional supplementation with the use of botanicals that effectively increase insulin sensitivity represent a very attractive and novel approach for future studies designed to intervene in the development of metabolic syndrome. The proposed study will benefit the value added agriculture of the State of NJ and provide tangible benefits to the biotechnology and pharmaceutical industries in the State. NJ farmers will benefit from the technologies because they will be provided with the opportunity to grow new crops with a greater value since the crops will contain bioactive compounds useful for the treatment and prevention of diabetes and metabolic syndrome. Pharmaceutical and nutraceutical companies will use the processed plants as the source of novel ingredients for drugs, foods and or dietary supplements. Therefore, the proposed research will enable agriculture to generate tremendous value through pharmaceutical and nutraceutical manufacturing of products that will promote a healthier population and greener planet. Products that may prevent the onset of metabolic syndrome and diabetes will also save the health care system and State of NJ tremendous amounts of money.
<P>APPROACH: Methods. Isolation and characterization of the anti-diabetic compounds from Artemisia and Rubus will be guided by in vitro assays, in which the extract was found to be particularly active: 1) non-insulin mediated induction of glycogen accumulation in muscle cells and 2) adiponectin gene expression in adipocytes. Step 1. Fractions of the extracts will be separated and analyzed by preparatory HPLC on a C-8 reverse phase column. Further optimization and fine-tuning of the chromatography conditions for the specific fractions being investigated will be performed. Chemical information, such as spectral data and molecular ions and MS/MS fragmentation fingerprint will be obtained in real time by directing part of the HPLC effluent toward a diode array and mass spectrometer. Compounds will be ionized by different ionization methods such as electrospray, electron impact, chemical ionization, photoionization to obtain maximum structural information. Mass analysis will be performed using quadrupole ion trap and time-of-flight (TOF) analyzer. Data will be collected and analyzed with the HPLC and MS OEM supplied software, linked with commercially available spectral libraries and the in-house library of plant natural products. This on-line structural analysis will help with the dereplication of the fractions avoiding isolation of well known compounds. Step 2. Structural characterization (deconvolution). High power nuclear magnetic resonance (NMR) instruments (up to 950 MHz available at NCSU) are capable of unequivocal structure determination using sub-milligram quantities of an isolated compound(s). These instruments can also produce structural information from samples of lesser purity. NMR facility at NCSU will be used to structurally characterize anti-diabetic compound(s) from Artemisia sp. and R. caesius. Center for Gastro-Intestinal Research (CGIR), a collaboration between Rutgers and the Dutch company TNO is focused on the use of the TNO gastroIntestinal Model (TIM), a complex, computer-controlled apparatus that closely simulates in vivo conditions of the gastrointestinal tract of humans. TIM will be used as for pre-clinical studies of bioavailability and intestinal fate of pharmacologically active components of R. caesius and their potential biochemical transformations in each compartment of the gastrointestinal system. In additions, the interaction of the extract and its active components with different diets (e.g. high and low fat, high protein, high carbohydrate) will be studied to determine the recommendations for potential human studies. The bioaccessibility of the active compounds in the TIM system will then be related to the disposition and bioavailability observed in the animal model in order to demonstrate which factors most negatively impact the bioactivity of the bioactive compounds in vivo and may be used to predict appropriate formulations and doses for clinical effects.