{"id":{"repo_id":"cent-lancashire","oai_identifier":"oai:clok.uclan.ac.uk:6655"},"canonical_url":"https://search.dev.ndltd.org/etd/cent-lancashire/oai:clok.uclan.ac.uk:6655","repository":{"repo_id":"cent-lancashire","name":"University of Central Lancashire","base_url":"https://clok.uclan.ac.uk/cgi/oai2"},"display":{"title":"The impact of diabetes on cardiac remodelling after myocardial infarction: potential role of thyroid hormone signalling","abstract":"Diabetes (DM) increases mortality after myocardial infarction and deteriorates post-ischaemic cardiac remodelling. This study investigated possible implications of thyroid hormone (TH) signalling in either reducing or preventing this response. TH signalling has a regulatory role in metabolism, cardiac function, growth and ischaemic stress. Acute myocardial infarction (AMI) was induced in age–match healthy control rats (AMI-C) and in streptozotocin (STZ)-induced type I diabetic (DM) animals (DM+AMI) using 35 mg/kg body weight while sham operated animals served as controls (SHAM). The results show that AMI in tissue hypothyroidism caused significant down-regulation of TH receptors, TRα1 and TRβ1, in the diabetic myocardium without changes in T3, T4 levels in plasma. This response was associated with increased expression of β-MHC and distinct changes in cardiac function and geometry. Ejection fractions (EF%) was decreased in DM-AMI as compared to DM+AMI animals. Systolic and diastolic chamber dimensions were increased without concomitant increase in wall thickness and thus, WTI (the ratio of LVIDd/2*Posterior Wall thickness), an index of wall stress, was significantly elevated. The absence of wall thickening in DM+AMI hearts was associated with changes in stretch-induced kinase hypertrophic signalling p38 MAPK. In contrast, ERK, p-ERK and p-p38 MAPK levels were not changed in DM+AMI as compared to non-infarcted hearts (DM+SHAM). TH administration after AMI prevented hypothyroidism and resulted in decreased β-MHC expression, increased wall thickening and normalized wall stress, while stretch-induced p38 MAPK activation was restored. The results show that diabetes can exacerbates post-ischaemic cardiac remodelling and tissue hypothyroidism and TH treatment can prevent this response and improve cardiac haemodynamics.","abstract_html":"Diabetes (DM) increases mortality after myocardial infarction and deteriorates post-ischaemic cardiac remodelling. This study investigated possible implications of thyroid hormone (TH) signalling in either reducing or preventing this response. TH signalling has a regulatory role in metabolism, cardiac function, growth and ischaemic stress. Acute myocardial infarction (AMI) was induced in age–match healthy control rats (AMI-C) and in streptozotocin (STZ)-induced type I diabetic (DM) animals (DM+AMI) using 35 mg/kg body weight while sham operated animals served as controls (SHAM). The results show that AMI in tissue hypothyroidism caused significant down-regulation of TH receptors, TRα1 and TRβ1, in the diabetic myocardium without changes in T3, T4 levels in plasma. This response was associated with increased expression of β-MHC and distinct changes in cardiac function and geometry. Ejection fractions (EF%) was decreased in DM-AMI as compared to DM+AMI animals. Systolic and diastolic chamber dimensions were increased without concomitant increase in wall thickness and thus, WTI (the ratio of LVIDd/2*Posterior Wall thickness), an index of wall stress, was significantly elevated. The absence of wall thickening in DM+AMI hearts was associated with changes in stretch-induced kinase hypertrophic signalling p38 MAPK. In contrast, ERK, p-ERK and p-p38 MAPK levels were not changed in DM+AMI as compared to non-infarcted hearts (DM+SHAM). TH administration after AMI prevented hypothyroidism and resulted in decreased β-MHC expression, increased wall thickening and normalized wall stress, while stretch-induced p38 MAPK activation was restored. The results show that diabetes can exacerbates post-ischaemic cardiac remodelling and tissue hypothyroidism and TH treatment can prevent this response and improve cardiac haemodynamics.","abstract_has_math":false,"creators":["Kalofutis, Christos"],"institution":"University of Central Lancashire","degree_name":"phd","degree_level":"doctoral","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2012,"date_issued":"2012-11","date_published":"2012-11","updated_at":"2026-07-24T01:35:38Z","subjects":[],"languages":["en"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":null,"outbound_label":null,"outbound_source":null},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Kalofutis, Christos"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2012-11"]},{"key":"dc:date.issued","label":"Date","values":["2012-11"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["School of Pharmacy and Biomedical Sciences"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Central Lancashire"]},{"key":"dc:relation.isreferencedby","label":"Dc Relation Isreferencedby","values":["https://knowledge.lancashire.ac.uk/id/eprint/6655/"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["doctoral"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["phd"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://knowledge.lancashire.ac.uk/id/eprint/6655/1/Kalofoutis%20Christos%20Final%20e-Thesis%20%28Master%20Copy%29.pdf","https://knowledge.lancashire.ac.uk/id/eprint/6655/7/Kalofoutis%20Christos%20e-Thesis%20Submission%20Form.doc"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Diabetes (DM) increases mortality after myocardial infarction and deteriorates post-ischaemic cardiac remodelling. This study investigated possible implications of thyroid hormone (TH) signalling in either reducing or preventing this response. TH signalling has a regulatory role in metabolism, cardiac function, growth and ischaemic stress. Acute myocardial infarction (AMI) was induced in age–match healthy control rats (AMI-C) and in streptozotocin (STZ)-induced type I diabetic (DM) animals (DM+AMI) using 35 mg/kg body weight while sham operated animals served as controls (SHAM). The results show that AMI in tissue hypothyroidism caused significant down-regulation of TH receptors, TRα1 and TRβ1, in the diabetic myocardium without changes in T3, T4 levels in plasma. This response was associated with increased expression of β-MHC and distinct changes in cardiac function and geometry. Ejection fractions (EF%) was decreased in DM-AMI as compared to DM+AMI animals. Systolic and diastolic chamber dimensions were increased without concomitant increase in wall thickness and thus, WTI (the ratio of LVIDd/2*Posterior Wall thickness), an index of wall stress, was significantly elevated. The absence of wall thickening in DM+AMI hearts was associated with changes in stretch-induced kinase hypertrophic signalling p38 MAPK. In contrast, ERK, p-ERK and p-p38 MAPK levels were not changed in DM+AMI as compared to non-infarcted hearts (DM+SHAM). TH administration after AMI prevented hypothyroidism and resulted in decreased β-MHC expression, increased wall thickening and normalized wall stress, while stretch-induced p38 MAPK activation was restored. The results show that diabetes can exacerbates post-ischaemic cardiac remodelling and tissue hypothyroidism and TH treatment can prevent this response and improve cardiac haemodynamics."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf","application/msword"]},{"key":"dc:title","label":"Title","values":["The impact of diabetes on cardiac remodelling after myocardial infarction: potential role of thyroid hormone signalling"]}]}],"canonical_facts":{"dc:creator":["Kalofutis, Christos"],"dc:date":["2012-11"],"dc:date.issued":["2012-11"],"dc:description.abstract":["Diabetes (DM) increases mortality after myocardial infarction and deteriorates post-ischaemic cardiac remodelling. This study investigated possible implications of thyroid hormone (TH) signalling in either reducing or preventing this response. TH signalling has a regulatory role in metabolism, cardiac function, growth and ischaemic stress. Acute myocardial infarction (AMI) was induced in age–match healthy control rats (AMI-C) and in streptozotocin (STZ)-induced type I diabetic (DM) animals (DM+AMI) using 35 mg/kg body weight while sham operated animals served as controls (SHAM). The results show that AMI in tissue hypothyroidism caused significant down-regulation of TH receptors, TRα1 and TRβ1, in the diabetic myocardium without changes in T3, T4 levels in plasma. This response was associated with increased expression of β-MHC and distinct changes in cardiac function and geometry. Ejection fractions (EF%) was decreased in DM-AMI as compared to DM+AMI animals. Systolic and diastolic chamber dimensions were increased without concomitant increase in wall thickness and thus, WTI (the ratio of LVIDd/2*Posterior Wall thickness), an index of wall stress, was significantly elevated. The absence of wall thickening in DM+AMI hearts was associated with changes in stretch-induced kinase hypertrophic signalling p38 MAPK. In contrast, ERK, p-ERK and p-p38 MAPK levels were not changed in DM+AMI as compared to non-infarcted hearts (DM+SHAM). TH administration after AMI prevented hypothyroidism and resulted in decreased β-MHC expression, increased wall thickening and normalized wall stress, while stretch-induced p38 MAPK activation was restored. The results show that diabetes can exacerbates post-ischaemic cardiac remodelling and tissue hypothyroidism and TH treatment can prevent this response and improve cardiac haemodynamics."],"dc:format":["application/pdf","application/msword"],"dc:identifier.uri":["https://knowledge.lancashire.ac.uk/id/eprint/6655/1/Kalofoutis%20Christos%20Final%20e-Thesis%20%28Master%20Copy%29.pdf","https://knowledge.lancashire.ac.uk/id/eprint/6655/7/Kalofoutis%20Christos%20e-Thesis%20Submission%20Form.doc"],"dc:language":["en"],"dc:publisher.department":["School of Pharmacy and Biomedical Sciences"],"dc:publisher.institution":["University of Central Lancashire"],"dc:relation.isreferencedby":["https://knowledge.lancashire.ac.uk/id/eprint/6655/"],"dc:title":["The impact of diabetes on cardiac remodelling after myocardial infarction: potential role of thyroid hormone signalling"],"dc:type":["Thesis"],"dc:type.qualificationlevel":["doctoral"],"dc:type.qualificationname":["phd"]},"updated_at":"2026-07-24T01:35:38Z"}