{"id":{"repo_id":"utmb","oai_identifier":"oai:utmb-ir.tdl.org:2152.3/184"},"canonical_url":"https://search.dev.ndltd.org/etd/utmb/oai:utmb-ir.tdl.org:2152.3/184","repository":{"repo_id":"utmb","name":"University of Texas Medical Branch","base_url":"https://utmb-ir.tdl.org/server/oai/request"},"display":{"title":"Effect of vasodilation on the response of muscle protein synthesis to insulin in aging","abstract":"The loss of muscle with aging (sarcopenia) is an important contributor to disability and physical dependence in older people. Studies have recently found that aging is associated with a relative resistance of muscle proteins to the anabolic action of insulin, even in subjects who do not have diabetes. This alteration impairs the response of older muscle to the anabolic action of a mixed meal, and may contribute to muscle loss with aging. \\r\\nThe hypothesis is that aging reduces the vascular sensitivity to insulin, which prevents the physiological increase in blood flow and muscle perfusion in response to exogenous or endogenous insulin, thereby decreasing the response of muscle protein synthesis and net balance to the anabolic action of insulin. This study looked at whether the response of muscle protein synthesis and net balance to insulin improves in older subjects when blood flow and muscle perfusion are pharmacologically restored to youthful values. \\r\\nSix elderly subjects were assigned to a control group which received an insulin infusion in one leg during the intervention period. Another six subjects in the experimental group received insulin as well as the vasodilator, sodium nitroprusside (SNP). Blood flow increased significantly (P<0.001) with the addition of SNP. Using stable isotope methodologies, it was determined that there were also increases in muscle protein anabolism with the addition of SNP. The muscle protein synthesis (mTOR-associated) cell signaling pathways also showed increased phosphorylation of specific insulin-related proteins when vasodilation was increased with SNP.\\r\\nTherefore, this study showed that pharmacologically restoring blood flow and nutrient delivery to youthful values, did improve the response of muscle protein synthesis to insulin in older subjects. Decreases in blood flow and muscle perfusion are clearly important contributors to the insulin resistance of skeletal muscle in aging. Understanding the mechanisms behind the loss of muscle with aging will serve as a basis for developing effective treatments for sarcopenia in older individuals.","abstract_html":"The loss of muscle with aging (sarcopenia) is an important contributor to disability and physical dependence in older people. Studies have recently found that aging is associated with a relative resistance of muscle proteins to the anabolic action of insulin, even in subjects who do not have diabetes. This alteration impairs the response of older muscle to the anabolic action of a mixed meal, and may contribute to muscle loss with aging. \\r\\nThe hypothesis is that aging reduces the vascular sensitivity to insulin, which prevents the physiological increase in blood flow and muscle perfusion in response to exogenous or endogenous insulin, thereby decreasing the response of muscle protein synthesis and net balance to the anabolic action of insulin. This study looked at whether the response of muscle protein synthesis and net balance to insulin improves in older subjects when blood flow and muscle perfusion are pharmacologically restored to youthful values. \\r\\nSix elderly subjects were assigned to a control group which received an insulin infusion in one leg during the intervention period. Another six subjects in the experimental group received insulin as well as the vasodilator, sodium nitroprusside (SNP). Blood flow increased significantly (P<0.001) with the addition of SNP. Using stable isotope methodologies, it was determined that there were also increases in muscle protein anabolism with the addition of SNP. The muscle protein synthesis (mTOR-associated) cell signaling pathways also showed increased phosphorylation of specific insulin-related proteins when vasodilation was increased with SNP.\\r\\nTherefore, this study showed that pharmacologically restoring blood flow and nutrient delivery to youthful values, did improve the response of muscle protein synthesis to insulin in older subjects. Decreases in blood flow and muscle perfusion are clearly important contributors to the insulin resistance of skeletal muscle in aging. Understanding the mechanisms behind the loss of muscle with aging will serve as a basis for developing effective treatments for sarcopenia in older individuals.","abstract_has_math":false,"creators":["Jessica Lan Lee"],"institution":"The University of Texas Medical Branch","degree_name":"Master of Science","degree_level":"Master","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Elena Volpi"],"committee_chairs":[],"committee_members":["Melinda Sheffield-Moore","Blake Rasmussen"],"year":2008,"date_issued":"2008-07-14","date_published":"2008-07-14","updated_at":"2026-07-24T05:51:04Z","subjects":["skeletal muscle","muscle metabolism","insulin signaling pathway"],"languages":["eng"],"rights":["Copyright © is held by the author. Presentation of this material on the TDL web site by The University of Texas Medical Branch at Galveston was made possible under a limited license grant from the author who has retained all copyrights in the works."],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-07242008-141823"],"render_values":[{"text":"etd-07242008-141823","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2152.3/184","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Elena Volpi"]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Melinda Sheffield-Moore","Blake Rasmussen"]},{"key":"dc:creator","label":"Author","values":["Jessica Lan Lee"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2011-12-20T16:05:04Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2008-12-09","2011-12-20T16:05:04Z"]},{"key":"dc:date.issued","label":"Date","values":["2008-07-14"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Master"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["The University of Texas Medical Branch"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["skeletal muscle","muscle metabolism","insulin signaling pathway"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright © is held by the author. Presentation of this material on the TDL web site by The University of Texas Medical Branch at Galveston was made possible under a limited license grant from the author who has retained all copyrights in the works."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-07242008-141823"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/2152.3/184"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The loss of muscle with aging (sarcopenia) is an important contributor to disability and physical dependence in older people. Studies have recently found that aging is associated with a relative resistance of muscle proteins to the anabolic action of insulin, even in subjects who do not have diabetes. This alteration impairs the response of older muscle to the anabolic action of a mixed meal, and may contribute to muscle loss with aging. \\r\\nThe hypothesis is that aging reduces the vascular sensitivity to insulin, which prevents the physiological increase in blood flow and muscle perfusion in response to exogenous or endogenous insulin, thereby decreasing the response of muscle protein synthesis and net balance to the anabolic action of insulin. This study looked at whether the response of muscle protein synthesis and net balance to insulin improves in older subjects when blood flow and muscle perfusion are pharmacologically restored to youthful values. \\r\\nSix elderly subjects were assigned to a control group which received an insulin infusion in one leg during the intervention period. Another six subjects in the experimental group received insulin as well as the vasodilator, sodium nitroprusside (SNP). Blood flow increased significantly (P<0.001) with the addition of SNP. Using stable isotope methodologies, it was determined that there were also increases in muscle protein anabolism with the addition of SNP. The muscle protein synthesis (mTOR-associated) cell signaling pathways also showed increased phosphorylation of specific insulin-related proteins when vasodilation was increased with SNP.\\r\\nTherefore, this study showed that pharmacologically restoring blood flow and nutrient delivery to youthful values, did improve the response of muscle protein synthesis to insulin in older subjects. Decreases in blood flow and muscle perfusion are clearly important contributors to the insulin resistance of skeletal muscle in aging. Understanding the mechanisms behind the loss of muscle with aging will serve as a basis for developing effective treatments for sarcopenia in older individuals."]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["electronic"]},{"key":"dc:title","label":"Title","values":["Effect of vasodilation on the response of muscle protein synthesis to insulin in aging"]}]}],"canonical_facts":{"dc:contributor.advisor":["Elena Volpi"],"dc:contributor.committeemember":["Melinda Sheffield-Moore","Blake Rasmussen"],"dc:creator":["Jessica Lan Lee"],"dc:date.accessioned":["2011-12-20T16:05:04Z"],"dc:date.available":["2008-12-09","2011-12-20T16:05:04Z"],"dc:date.issued":["2008-07-14"],"dc:description.abstract":["The loss of muscle with aging (sarcopenia) is an important contributor to disability and physical dependence in older people. Studies have recently found that aging is associated with a relative resistance of muscle proteins to the anabolic action of insulin, even in subjects who do not have diabetes. This alteration impairs the response of older muscle to the anabolic action of a mixed meal, and may contribute to muscle loss with aging. \\r\\nThe hypothesis is that aging reduces the vascular sensitivity to insulin, which prevents the physiological increase in blood flow and muscle perfusion in response to exogenous or endogenous insulin, thereby decreasing the response of muscle protein synthesis and net balance to the anabolic action of insulin. This study looked at whether the response of muscle protein synthesis and net balance to insulin improves in older subjects when blood flow and muscle perfusion are pharmacologically restored to youthful values. \\r\\nSix elderly subjects were assigned to a control group which received an insulin infusion in one leg during the intervention period. Another six subjects in the experimental group received insulin as well as the vasodilator, sodium nitroprusside (SNP). Blood flow increased significantly (P<0.001) with the addition of SNP. Using stable isotope methodologies, it was determined that there were also increases in muscle protein anabolism with the addition of SNP. The muscle protein synthesis (mTOR-associated) cell signaling pathways also showed increased phosphorylation of specific insulin-related proteins when vasodilation was increased with SNP.\\r\\nTherefore, this study showed that pharmacologically restoring blood flow and nutrient delivery to youthful values, did improve the response of muscle protein synthesis to insulin in older subjects. Decreases in blood flow and muscle perfusion are clearly important contributors to the insulin resistance of skeletal muscle in aging. Understanding the mechanisms behind the loss of muscle with aging will serve as a basis for developing effective treatments for sarcopenia in older individuals."],"dc:format.medium":["electronic"],"dc:identifier.other":["etd-07242008-141823"],"dc:identifier.uri":["http://hdl.handle.net/2152.3/184"],"dc:language.iso":["eng"],"dc:rights":["Copyright © is held by the author. Presentation of this material on the TDL web site by The University of Texas Medical Branch at Galveston was made possible under a limited license grant from the author who has retained all copyrights in the works."],"dc:subject":["skeletal muscle","muscle metabolism","insulin signaling pathway"],"dc:title":["Effect of vasodilation on the response of muscle protein synthesis to insulin in aging"],"thesis:degree_level":["Master"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["The University of Texas Medical Branch"]},"updated_at":"2026-07-24T05:51:04Z"}