EDITORIAL Applications of Biotechnology in Nutrition disease mechanisms and explore nutrient/host interactions. Studies described by McGrane and Hanson further detail and illustrate the regulatory properties of nutrients upon metabolism and how they may be influenced through gene transfer studies. These au-
There has been considerable interest in the application of molecular biological techniques to all levels of nutritional science. These areas include: 1. basic research used to understand the fundamental mechanisms of metabolic disease and how they may
thors employ transgenic animals to illustrate the use of a fusion gene composed of a nutrient-sensitive regulatory region and a region coding for a growthpromoting protein (growth hormone). Not only does this model yield valuable information regarding how gene expression is regulated, it may yield practical benefits in the form of genetically engineered animals that exhibit &dquo;super properties.&dquo; Dairy animals may eventually be designed to exhibit special qualities, such as leaner meat or a greater efficiency in milk production.’ Although most recombinant proteins are currently produced in genetically engineered bacteria, this approach may eventually be replaced in its entirety by transgenic animals that can produce a variety of biologically equivalent natural human proteins in large quantities.’ The remarkable ability to transfer genes across species lines has been demonstrated, and the generation of human proteins in large quantities from animal &dquo;bioreactors&dquo; is already a reality.’ Transgenesis will undoubtedly have a broad effect on nutrition. The use of gene transfer methods to ameliorate certain disease processes is also undergoing experimental as well as clinical evaluation. The therapeutic prototype of gene therapy is illustrated in the report by McGrane and Hanson. They describe the construction of a transgenic animal model expressing the lowdensity lipoprotein (LDL) receptor in which its rate of production is not subject to the normal inhibitory influences of cholesterol. This overexpression of the LDL receptor gene results in a reduced plasma cholesterol, which presumably could influence the course of atherogenesis in a positive manner. These studies are not simply laboratory curiosities, as evidenced by a current proposal pending with the National Institutes of Health awaiting approval for an LDL receptor gene transfer study in human subjects.’ The application of genetic technology to the disciplines of nutrition and medicine has resulted in tremendous strides especially over the past 10 years. It has evolved from a field that was burdened with a negative public image to one that currently enjoys an unprecedented level of activity and interest. Applied
be 2.
favorably modified. &dquo;therapeutics&dquo; whereby specific nutrients or regulatory factors, such as hormones, are used to modify gene expression and ultimately whole body metabolism.
3.
&dquo;diagnostics&dquo; used for the definition of metabolic and nutrition disorders that may involve a genetic basis.
For the clinical nutritionist, the latter two cateare the most inviting, probably because they minimize the need for a fundamental biochemical background. The inclusion of molecular biology in all of these areas, however, is inescapable and will increasingly confront individuals who participate in patient care. Therein lies the necessity for establishing a conceptual knowledge and basic understanding of the vocabulary of molecular biology. For example, a recent issue of a generally read clinical journal (JAMA, volume 266, no. 13) devoted approximately 30% of space to contributions that use molecular biological techniques to draw primary conclusions. Although the field of biotechnology has not yet extensively infiltrated the major nutritional journals, it is simply a matter of time until this pervasive jargon is presented as the &dquo;tools of choice.&dquo; As pointed out aptly by both review articles in this issue, carbohydrate, protein, and lipid metabolism are strongly regulated at the gene level, making it almost self-evident that strategies to influence metabolic disorders will ultimately require a consideration of molecular biological methods. The article by Robert Smith has provided a thoughtful presentation of this field in a manner that is palatable to the general readership. The practical benefits that derive from biotechnology are also immediately identified. Recombinant proteins such as human insulin, growth hormone, insulin-like growth factor 1 and granulocytemacrophage colony-stimulating factor are currently in general clinical use or clinical trials. 1-3 Most biomedical research forums regularly use the methods described in Smith’s paper to investigate
gories
3
Downloaded from ncp.sagepub.com at EASTERN KENTUCKY UNIV on May 30, 2015
4
biotechnology will surely continue to increase its influence on the biomedical sciences, eventually yielding rich rewards for the
area
Detroit, Michigan REFERENCES
care
unit. JPEN 1990;14:574-81.
on
full
intravenous
nutritional
support.
JPEN
1990;14:437-41. 3.
Thompson WA, Coyle SM, Lazorus D,
et al. The metabolic effects of a continuous infusion of insulin-like growth factor (IGF-1) in parenterally fed man. Surg. Forum, 1991;42:23. 4. Steele NC, Pursel VG. Nutrient partitioning by transgenic
5.
Wright G, Carver A, Cottom D, et al. High level expression of active human alpha-1-antitrypsin in the milk of transgenic sheep. Biotechnology 1991;9:830-4. Moffat AS. Transgenic animals may be down on the pharm.
animals. Annu Rev Nutr 1990;10:213-32.
6.
Ziegler TR, Young LS, Ferrari-Baliviera E, et al. Use of human growth hormone combined with nutritional support in a critical
Ponting GA, Ward HC, Halliday D, et al. Protein and energy metabolism with biosynthetic human growth hormone in patients
of clinical nutrition. Michael S. Dahn, MD, PhD Department of Surgery Wayne State University
1.
2.
Science 1991;254:35-6. C. Gene therapy trials
7. Holden
1991;254:372.
Downloaded from ncp.sagepub.com at EASTERN KENTUCKY UNIV on May 30, 2015
on
the
move.
Science,
There has been considerable interest in the application of molecular biological techniques to all levels of nutritional science. These areas include: 1. basic research used to understand the fundamental mechanisms of metabolic disease and how they may
thors employ transgenic animals to illustrate the use of a fusion gene composed of a nutrient-sensitive regulatory region and a region coding for a growthpromoting protein (growth hormone). Not only does this model yield valuable information regarding how gene expression is regulated, it may yield practical benefits in the form of genetically engineered animals that exhibit &dquo;super properties.&dquo; Dairy animals may eventually be designed to exhibit special qualities, such as leaner meat or a greater efficiency in milk production.’ Although most recombinant proteins are currently produced in genetically engineered bacteria, this approach may eventually be replaced in its entirety by transgenic animals that can produce a variety of biologically equivalent natural human proteins in large quantities.’ The remarkable ability to transfer genes across species lines has been demonstrated, and the generation of human proteins in large quantities from animal &dquo;bioreactors&dquo; is already a reality.’ Transgenesis will undoubtedly have a broad effect on nutrition. The use of gene transfer methods to ameliorate certain disease processes is also undergoing experimental as well as clinical evaluation. The therapeutic prototype of gene therapy is illustrated in the report by McGrane and Hanson. They describe the construction of a transgenic animal model expressing the lowdensity lipoprotein (LDL) receptor in which its rate of production is not subject to the normal inhibitory influences of cholesterol. This overexpression of the LDL receptor gene results in a reduced plasma cholesterol, which presumably could influence the course of atherogenesis in a positive manner. These studies are not simply laboratory curiosities, as evidenced by a current proposal pending with the National Institutes of Health awaiting approval for an LDL receptor gene transfer study in human subjects.’ The application of genetic technology to the disciplines of nutrition and medicine has resulted in tremendous strides especially over the past 10 years. It has evolved from a field that was burdened with a negative public image to one that currently enjoys an unprecedented level of activity and interest. Applied
be 2.
favorably modified. &dquo;therapeutics&dquo; whereby specific nutrients or regulatory factors, such as hormones, are used to modify gene expression and ultimately whole body metabolism.
3.
&dquo;diagnostics&dquo; used for the definition of metabolic and nutrition disorders that may involve a genetic basis.
For the clinical nutritionist, the latter two cateare the most inviting, probably because they minimize the need for a fundamental biochemical background. The inclusion of molecular biology in all of these areas, however, is inescapable and will increasingly confront individuals who participate in patient care. Therein lies the necessity for establishing a conceptual knowledge and basic understanding of the vocabulary of molecular biology. For example, a recent issue of a generally read clinical journal (JAMA, volume 266, no. 13) devoted approximately 30% of space to contributions that use molecular biological techniques to draw primary conclusions. Although the field of biotechnology has not yet extensively infiltrated the major nutritional journals, it is simply a matter of time until this pervasive jargon is presented as the &dquo;tools of choice.&dquo; As pointed out aptly by both review articles in this issue, carbohydrate, protein, and lipid metabolism are strongly regulated at the gene level, making it almost self-evident that strategies to influence metabolic disorders will ultimately require a consideration of molecular biological methods. The article by Robert Smith has provided a thoughtful presentation of this field in a manner that is palatable to the general readership. The practical benefits that derive from biotechnology are also immediately identified. Recombinant proteins such as human insulin, growth hormone, insulin-like growth factor 1 and granulocytemacrophage colony-stimulating factor are currently in general clinical use or clinical trials. 1-3 Most biomedical research forums regularly use the methods described in Smith’s paper to investigate
gories
3
Downloaded from ncp.sagepub.com at EASTERN KENTUCKY UNIV on May 30, 2015
4
biotechnology will surely continue to increase its influence on the biomedical sciences, eventually yielding rich rewards for the
area
Detroit, Michigan REFERENCES
care
unit. JPEN 1990;14:574-81.
on
full
intravenous
nutritional
support.
JPEN
1990;14:437-41. 3.
Thompson WA, Coyle SM, Lazorus D,
et al. The metabolic effects of a continuous infusion of insulin-like growth factor (IGF-1) in parenterally fed man. Surg. Forum, 1991;42:23. 4. Steele NC, Pursel VG. Nutrient partitioning by transgenic
5.
Wright G, Carver A, Cottom D, et al. High level expression of active human alpha-1-antitrypsin in the milk of transgenic sheep. Biotechnology 1991;9:830-4. Moffat AS. Transgenic animals may be down on the pharm.
animals. Annu Rev Nutr 1990;10:213-32.
6.
Ziegler TR, Young LS, Ferrari-Baliviera E, et al. Use of human growth hormone combined with nutritional support in a critical
Ponting GA, Ward HC, Halliday D, et al. Protein and energy metabolism with biosynthetic human growth hormone in patients
of clinical nutrition. Michael S. Dahn, MD, PhD Department of Surgery Wayne State University
1.
2.
Science 1991;254:35-6. C. Gene therapy trials
7. Holden
1991;254:372.
Downloaded from ncp.sagepub.com at EASTERN KENTUCKY UNIV on May 30, 2015
on
the
move.
Science,
