{"id":{"repo_id":"kings","oai_identifier":"oai:kclpure.kcl.ac.uk:studenttheses/c75d417f-13f8-4618-91de-96ce798a8336"},"canonical_url":"https://search.dev.ndltd.org/etd/kings/oai:kclpure.kcl.ac.uk:studenttheses/c75d417f-13f8-4618-91de-96ce798a8336","repository":{"repo_id":"kings","name":"King's College London","base_url":"https://kclpure.kcl.ac.uk/ws/oai"},"display":{"title":"Investigating the molecular underpinnings of major depressive disorder and the utility of biomarkers in the inflammatory cytokine pathway as aids for clinical diagnosis and treatment selection","abstract":"Major depressive disorder (MDD) is a complex, heterogeneous disorder<br/>characterised by a pathological distortion of emotional mood. There is evidence<br/>of both genetic and environmental risk factors for MDD, and gene-environment<br/>interactions may play a particularly important role. Clinically, MDD is defined by<br/>patients meeting a number of diagnostic criteria. However, the heterogeneous<br/>nature of the disorder can make MDD difficult to diagnose, especially as it<br/>shares close similarities with other psychiatric illnesses such as bipolar disorder.<br/>Another clinical problem is that antidepressants, the first line of treatment for<br/>MDD, are ineffective in a significant proportion of patients. The projects in this<br/>thesis address four aims: (i) the identification of novel gene-environment<br/>interactions which may increase risk for MDD; (ii) the identification of diagnostic<br/>biomarkers for MDD; (iii) the identification of biomarkers for the prediction of<br/>treatment response to antidepressants; and (iv) the identification of<br/>transcriptional changes associated with antidepressant treatment and successful<br/>therapeutic response.<br/>Utilising a model of early life stress in two inbred mouse strains, we<br/>investigated the transcriptional effects of maternal separation. The top stress by<br/>strain interaction was found in the telomerase RNA component gene (Terc). We<br/>also found that a single nucleotide polymorphism in TERC (rs10936599),<br/>previously identified as a predictor of telomere length, interacted with childhood<br/>neglect to predict MDD in a human case-control cohort.<br/>A study investigating differences in the transcription of inflammatory<br/>cytokines in the blood of MDD patients, bipolar disorder patients and controls,<br/>revealed disorder-specific differences in chemokine (C-C motif) ligand 24 and CC<br/>chemokine receptor type 6 which specifically differentiated MDD patients.<br/>Furthermore, we found that transcription of tumour necrosis factor and its targets<br/>in the inflammatory cytokine pathway, and DNA methylation in interleukin-11<br/>could be used to predict antidepressant response amongst MDD patients.<br/>Moreover, transcription of ATP-binding cassette sub-family F member 1 was<br/>found to increase on antidepressant treatment, with the magnitude of change<br/>corresponding to clinical response.","abstract_html":"Major depressive disorder (MDD) is a complex, heterogeneous disorder&lt;br/&gt;characterised by a pathological distortion of emotional mood. There is evidence&lt;br/&gt;of both genetic and environmental risk factors for MDD, and gene-environment&lt;br/&gt;interactions may play a particularly important role. Clinically, MDD is defined by&lt;br/&gt;patients meeting a number of diagnostic criteria. However, the heterogeneous&lt;br/&gt;nature of the disorder can make MDD difficult to diagnose, especially as it&lt;br/&gt;shares close similarities with other psychiatric illnesses such as bipolar disorder.&lt;br/&gt;Another clinical problem is that antidepressants, the first line of treatment for&lt;br/&gt;MDD, are ineffective in a significant proportion of patients. The projects in this&lt;br/&gt;thesis address four aims: (i) the identification of novel gene-environment&lt;br/&gt;interactions which may increase risk for MDD; (ii) the identification of diagnostic&lt;br/&gt;biomarkers for MDD; (iii) the identification of biomarkers for the prediction of&lt;br/&gt;treatment response to antidepressants; and (iv) the identification of&lt;br/&gt;transcriptional changes associated with antidepressant treatment and successful&lt;br/&gt;therapeutic response.&lt;br/&gt;Utilising a model of early life stress in two inbred mouse strains, we&lt;br/&gt;investigated the transcriptional effects of maternal separation. The top stress by&lt;br/&gt;strain interaction was found in the telomerase RNA component gene (Terc). We&lt;br/&gt;also found that a single nucleotide polymorphism in TERC (rs10936599),&lt;br/&gt;previously identified as a predictor of telomere length, interacted with childhood&lt;br/&gt;neglect to predict MDD in a human case-control cohort.&lt;br/&gt;A study investigating differences in the transcription of inflammatory&lt;br/&gt;cytokines in the blood of MDD patients, bipolar disorder patients and controls,&lt;br/&gt;revealed disorder-specific differences in chemokine (C-C motif) ligand 24 and CC&lt;br/&gt;chemokine receptor type 6 which specifically differentiated MDD patients.&lt;br/&gt;Furthermore, we found that transcription of tumour necrosis factor and its targets&lt;br/&gt;in the inflammatory cytokine pathway, and DNA methylation in interleukin-11&lt;br/&gt;could be used to predict antidepressant response amongst MDD patients.&lt;br/&gt;Moreover, transcription of ATP-binding cassette sub-family F member 1 was&lt;br/&gt;found to increase on antidepressant treatment, with the magnitude of change&lt;br/&gt;corresponding to clinical response.","abstract_has_math":false,"creators":["Powell, Tim"],"institution":"King's College London","degree_name":"Doctor of Philosophy","degree_level":"Doctoral Thesis","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Schalkwyk, Leonard Cornelis","Mill, Jonathan"],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-3-1","date_published":"2014-3-1","updated_at":"2026-07-24T02:44:42Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["oai:kclpure.kcl.ac.uk:studenttheses/c75d417f-13f8-4618-91de-96ce798a8336"],"render_values":[{"text":"oai:kclpure.kcl.ac.uk:studenttheses/c75d417f-13f8-4618-91de-96ce798a8336","href":null,"code":true}]}]},"links":{"outbound_url":"https://kclpure.kcl.ac.uk/portal/en/studentTheses/c75d417f-13f8-4618-91de-96ce798a8336","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Schalkwyk, Leonard Cornelis","Mill, Jonathan"]},{"key":"dc:creator","label":"Author","values":["Powell, Tim"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2014-3-1"]},{"key":"dc:date.issued","label":"Date","values":["2014-3-1"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Social Genetic & Developmental Psychiatry"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["King's College London"]},{"key":"dc:relation.isreferencedby","label":"Dc Relation Isreferencedby","values":["https://kclpure.kcl.ac.uk/portal/en/studentTheses/c75d417f-13f8-4618-91de-96ce798a8336"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Doctoral Thesis"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["Doctor of Philosophy"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["oai:kclpure.kcl.ac.uk:studenttheses/c75d417f-13f8-4618-91de-96ce798a8336","https://kclpure.kcl.ac.uk/portal/en/studentTheses/c75d417f-13f8-4618-91de-96ce798a8336"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://kclpure.kcl.ac.uk/portal/files/13519098/Studentthesis-Tim_Powell_2014.pdf"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Major depressive disorder (MDD) is a complex, heterogeneous disorder<br/>characterised by a pathological distortion of emotional mood. There is evidence<br/>of both genetic and environmental risk factors for MDD, and gene-environment<br/>interactions may play a particularly important role. Clinically, MDD is defined by<br/>patients meeting a number of diagnostic criteria. However, the heterogeneous<br/>nature of the disorder can make MDD difficult to diagnose, especially as it<br/>shares close similarities with other psychiatric illnesses such as bipolar disorder.<br/>Another clinical problem is that antidepressants, the first line of treatment for<br/>MDD, are ineffective in a significant proportion of patients. The projects in this<br/>thesis address four aims: (i) the identification of novel gene-environment<br/>interactions which may increase risk for MDD; (ii) the identification of diagnostic<br/>biomarkers for MDD; (iii) the identification of biomarkers for the prediction of<br/>treatment response to antidepressants; and (iv) the identification of<br/>transcriptional changes associated with antidepressant treatment and successful<br/>therapeutic response.<br/>Utilising a model of early life stress in two inbred mouse strains, we<br/>investigated the transcriptional effects of maternal separation. The top stress by<br/>strain interaction was found in the telomerase RNA component gene (Terc). We<br/>also found that a single nucleotide polymorphism in TERC (rs10936599),<br/>previously identified as a predictor of telomere length, interacted with childhood<br/>neglect to predict MDD in a human case-control cohort.<br/>A study investigating differences in the transcription of inflammatory<br/>cytokines in the blood of MDD patients, bipolar disorder patients and controls,<br/>revealed disorder-specific differences in chemokine (C-C motif) ligand 24 and CC<br/>chemokine receptor type 6 which specifically differentiated MDD patients.<br/>Furthermore, we found that transcription of tumour necrosis factor and its targets<br/>in the inflammatory cytokine pathway, and DNA methylation in interleukin-11<br/>could be used to predict antidepressant response amongst MDD patients.<br/>Moreover, transcription of ATP-binding cassette sub-family F member 1 was<br/>found to increase on antidepressant treatment, with the magnitude of change<br/>corresponding to clinical response."]},{"key":"dc:title","label":"Title","values":["Investigating the molecular underpinnings of major depressive disorder and the utility of biomarkers in the inflammatory cytokine pathway as aids for clinical diagnosis and treatment selection"]}]}],"canonical_facts":{"dc:contributor.advisor":["Schalkwyk, Leonard Cornelis","Mill, Jonathan"],"dc:creator":["Powell, Tim"],"dc:date":["2014-3-1"],"dc:date.issued":["2014-3-1"],"dc:description.abstract":["Major depressive disorder (MDD) is a complex, heterogeneous disorder<br/>characterised by a pathological distortion of emotional mood. There is evidence<br/>of both genetic and environmental risk factors for MDD, and gene-environment<br/>interactions may play a particularly important role. Clinically, MDD is defined by<br/>patients meeting a number of diagnostic criteria. However, the heterogeneous<br/>nature of the disorder can make MDD difficult to diagnose, especially as it<br/>shares close similarities with other psychiatric illnesses such as bipolar disorder.<br/>Another clinical problem is that antidepressants, the first line of treatment for<br/>MDD, are ineffective in a significant proportion of patients. The projects in this<br/>thesis address four aims: (i) the identification of novel gene-environment<br/>interactions which may increase risk for MDD; (ii) the identification of diagnostic<br/>biomarkers for MDD; (iii) the identification of biomarkers for the prediction of<br/>treatment response to antidepressants; and (iv) the identification of<br/>transcriptional changes associated with antidepressant treatment and successful<br/>therapeutic response.<br/>Utilising a model of early life stress in two inbred mouse strains, we<br/>investigated the transcriptional effects of maternal separation. The top stress by<br/>strain interaction was found in the telomerase RNA component gene (Terc). We<br/>also found that a single nucleotide polymorphism in TERC (rs10936599),<br/>previously identified as a predictor of telomere length, interacted with childhood<br/>neglect to predict MDD in a human case-control cohort.<br/>A study investigating differences in the transcription of inflammatory<br/>cytokines in the blood of MDD patients, bipolar disorder patients and controls,<br/>revealed disorder-specific differences in chemokine (C-C motif) ligand 24 and CC<br/>chemokine receptor type 6 which specifically differentiated MDD patients.<br/>Furthermore, we found that transcription of tumour necrosis factor and its targets<br/>in the inflammatory cytokine pathway, and DNA methylation in interleukin-11<br/>could be used to predict antidepressant response amongst MDD patients.<br/>Moreover, transcription of ATP-binding cassette sub-family F member 1 was<br/>found to increase on antidepressant treatment, with the magnitude of change<br/>corresponding to clinical response."],"dc:identifier":["oai:kclpure.kcl.ac.uk:studenttheses/c75d417f-13f8-4618-91de-96ce798a8336","https://kclpure.kcl.ac.uk/portal/en/studentTheses/c75d417f-13f8-4618-91de-96ce798a8336"],"dc:identifier.uri":["https://kclpure.kcl.ac.uk/portal/files/13519098/Studentthesis-Tim_Powell_2014.pdf"],"dc:language":["eng"],"dc:publisher.department":["Social Genetic & Developmental Psychiatry"],"dc:publisher.institution":["King's College London"],"dc:relation.isreferencedby":["https://kclpure.kcl.ac.uk/portal/en/studentTheses/c75d417f-13f8-4618-91de-96ce798a8336"],"dc:title":["Investigating the molecular underpinnings of major depressive disorder and the utility of biomarkers in the inflammatory cytokine pathway as aids for clinical diagnosis and treatment selection"],"dc:type":["Thesis"],"dc:type.qualificationlevel":["Doctoral Thesis"],"dc:type.qualificationname":["Doctor of Philosophy"]},"updated_at":"2026-07-24T02:44:42Z"}