Robert Rucker - US grants

The etiology of idiopathic scoliosis remains obscure. Although it is known to be inherited in a polygenetic manner with variable transmission, consistent abnormalities have not been found. Among the various etiologies considered have been abnormalities in proteoglycan metabolism, muscle imbalance, variations in growth disturbance, and suggestions of abnormal neurologic innervation. At the University of California, Davis, there exists a group of inbred chickens which develop scoliosis. In these chickens there is increased solubility of collagen, signs of increased collagen metabolism and changes in stress relaxation patterns of spinal ligaments and tendons. The changes would suggest that there are problems in collagen cross-linkage or type distribution. Comparable studies in humans have resulted in similar findings, including increased hydroxyproline excretion. Scoliotic chickens and suitable controls will be studied both at various ages and with various degrees of severity of the disease. The cross-linking pattern of collagen will be investigated in tendon, bone, cartilage, and vertebrae. We also intend to fully charcacterize collagen in the scoliotic animal model and from scoliotic human tissue.

This grant is a competitive renewal of HL-15965 (Elastin Metabolism). Its specific aims are: 1) to study the expression and processing of elastin precursors during lung and aorta development, 2) to identify factors important to elastin deposition in normal and diseased lung and aorta; and 3) to clarify linkages between the crosslinking of elastin and steps important to elastin synthesis, degradation and turnover. In this regard, studies on the regulation of lysyl oxidase and its relationship to elastin deposition are included. By examining elastin and lysyl oxidase expression, we hope to clarify further several relationships important to elastin metabolism and elastin-related diseases. For example, we will address questions related to the relative importance of cross- linking to elastin deposition in perinatal lung and aorta, particularly during periods when elastin undergoes rapid synthesis. Further, proteinase instillation into the lung of adult animals effects rapid deposition of new elastin. We will examine this response as a means of assessing to what extent, the expression of tropoelastin isoforms is altered in developmental versus disease models. It is the hope that subsequent findings will be useful in better defining concepts important to understanding elastin's role in normal development and in pulmonary and arterial diseases. The methods will involve immunological, biochemical and molecular biology techniques in studies utilizing rodents or tissue explants from rodents or young chicks. Elastin mRNA activity and expression will be examined using cDNA probes derived from elastin gene fragments. The nature of translated products will be assessed in cell-free translation systems. In addition, lysyl oxidase will be studied by using antibodies to lysyl oxidase, improved methods for detecting and isolating lysyl oxidase, and eventually molecular probes.

vitamins; dietary mineral; nutrition; biomedical facility; clinical chemistry; protein isoforms; tocopherols; ascorbate; all trans retinol; carotene; ligands; isozymes; folate; dietary trace element; thiamine; vitamin B complex; clinical research; high performance liquid chromatography; human subject; nutrition related tag;

9977873
Patrick Brown
UC Davis



Abstract


This project involves the acquisition of instrumentation in support of the establishment of a Center for Elemental mass spectrometry at the University of California, Davis. The instrumentation to be purchased will be capable of isotope ratio and quantitative determination of elements. The proposed center, in combination with the recently NSF-funded facility for H, C, N and O isotope determination will provide a world-class facility for inorganic mass spectrometry. The instruments to be purchased include a normal resolution, inductively coupled plasma mass spectrometer (ICP-MS); an ICP-MS equipped with magnetic sector MS and multi-collector detection system (MC-ICP-MS); and an ICP optical emission spectrometer (ICP-OES). These instruments will have a broad user base that will make optimal use of their varied capabilities.

Many disciplines in the fields of biological, environmental , geological and engineering sciences require detailed knowledge of the chemical and isotopic compositions of naturally occurring and laboratory-synthesized materials. Of special interest to the biological and environmental sciences are, for example, the pathways of trace constituents in the food web, biological complexation and transformations of trace elements in plants, animals and aquatic organisms; the fate of contaminants in surface and sub-surface environments, and modeling of watershed dynamics. In the geological and engineering sciences knowledge of element abundance and isotopic composition are used to establish evolutionary trends from rock successions/suites; to constrain paleoenvironmental parameters and paleoclimates and characterize material properties. What is common among these diverse applications of trace elements and isotope systems is the requirement of analytical instrumentation capable of measuring elements and individual isotopes in samples with high precision and accuracy.

The requested instruments and sample introduction systems will provide analytical capabilities to characterize the chemical composition of high solute-containing samples and solute concentrations at extreme dilutions with high precision and accuracy.

Sixteen PIs and senior personnel associated with 9 campus departments, 15 graduate programs and three colleges directly support this proposal and a significant number of additional faculty will benefit directly. A large number of graduate and undergraduate students will also benefit from the proposed center through course work and individual research projects.

DESCRIPTION (adapted from the applicant's abstract): Pyrroloquinoline quinone (PQQ) and its derivatives are present in tissues and biological fluids at concentrations ranging from nanomolar to micormolar amounts. PQQ also elicits important physiological and developmental responses and improves growth, particularly during the neonatal period. The P.I.'s group has developed models to study the effects of PQQ deprivation. Accordingly, the primary objective of this proposal is to establish why PQQ functions as a growth factor or coenzyme in animals, and to establish why PQQ is nutritionally important during the period of neonatal development. Whether or not PQQ plays an essential role in metabolism, however, is controversial. Although there is good acceptance that PQQ has pharmacological activity, additional work is necessary to place PQQ in the category of a "conditional" nutrient., cofactor, or growth factor. The P.I.'s overall hypothesis is that PQQ or a related derivative is nutritionally important and is conditionally essential in a nutritional context. There are three principal aims: 1) to describe the physiological and nutrition effects of altered PQQ status at periods important to reproduction, lactation, and early development, 2) to determine how tissue levels of PQQ are regulated, and 3) to determine if PQQ synthesis occurs in mammalian cells. Methods are in place to permit nutritional studies at the current state of the art in this regard using chemically defined diets. Novel approaches are presented for the synthesis of radiochemically labeled forms of PQQ using plasmids containing recombinant genes for PQQ synthesis transfected into E.Coli. that are auxotrophic for PQQ precursors. Mass spectral analysis will be used to define PQQ and PQQ adducts.