Assessment of Changes in Metabolic Activity in Liver & Skeletal Muscle in Patients Suffering From Acromegaly
Assessment of Changes in Metabolic Activity in Liver & Skeletal Muscle in Patients Suffering From Acromegaly - a 31P/1H Magnetic Resonance Spectroscopy Pilot Study
Growth hormone (GH) plays a pivotal role in the regulation of body composition including ectopic lipid deposition in insulin sensitive organs like liver and skeletal muscle. Recent evidence indicates that the GH-IGF1 axis affects body composition via regulating mitochondrial oxidation capacity.
Thus, excessive GH secretion by a pituitary adenoma (Acromegaly) might be accompanied by increased mitochondrial activity leading to inappropriately low intracellular lipid depots, especially in metabolically active tissue like liver and skeletal muscle.
This study aims to assess metabolic activity and intracellular lipid content in skeletal muscle and liver in patients suffering from acromegaly compared to controls by 31P/1H Magnetic resonance spectroscopy before and in follow up examinations 3, 6 and 12 months after initiation of GH lowering treatments including surgery, somatostatinanalogs or pegvisomant, as well as oral glucose tolerance tests at each examination to assess treatment responses and calculate validated parameters for insulin sensitivity and resistance.
연구 개요
상태
정황
상세 설명
Background: Growth hormone (GH) plays a pivotal role in the regulation of body composition including ectopic lipid deposition in insulin sensitive organs like liver and skeletal muscle. Direct inhibition of growth hormone action by a receptor antagonist has been shown to induce hepatic steatosis and growth hormone replacement decreases liver fat content in obese humans. Of note, recent evidence indicates that the GH-IGF1 axis affects body composition via regulating mitochondrial oxidation capacity.
Hypothesis: Direct and/or indirect effects of GH on mitochondrial function might mediate the changes in body composition and lipid deposition. Thus, excessive GH secretion by a pituitary adenoma (Acromegaly) might be accompanied by increased mitochondrial activity leading to inappropriately low intracellular lipid depots, especially in metabolically active tissue like liver and skeletal muscle.
Aim: Assessment of metabolic activity and intracellular lipid content in skeletal muscle and liver in patients suffering from acromegaly compared to controls.
Methods: Non-interventional study:
- 31P/1H Magnetic resonance spectroscopy before and in follow up examinations 3, 6 and 12 months after initiation of GH lowering treatments including surgery, somatostatinanalogs or pegvisomant.
- oral glucose tolerance tests at each examination to assess treatment responses and calculate validated parameters for insulin sensitivity and resistance.
연구 유형
등록 (예상)
연락처 및 위치
연구 장소
-
-
-
Vienna, 오스트리아, 1090
- 모병
- Medical University of Vienna, Department of Internal Medicine III
-
연락하다:
- Peter Wolf, MD
- 전화번호: 00431404004311
- 이메일: peter.wolf@meduniwien.ac.at
-
수석 연구원:
- Michael Krebs, MD, Prof
-
-
참여기준
자격 기준
공부할 수 있는 나이
건강한 자원 봉사자를 받아들입니다
연구 대상 성별
샘플링 방법
연구 인구
설명
Inclusion Criteria:
- age between 18-75 years
Exclusion Criteria:
- (known) overt diabetes mellitus
- known coronary artery disease (history of myocardial infarction or angina pectoris)
- acute or chronic (inflammatory, metabolic [hyperlipidemia, arterial hypertension, thyroid disorder]) disease (healthy controls)
- intake of medication potentially affecting glucose or lipid metabolism
- metal devices or other magnetic material in or on the subjects body which will be hazardous for NMR investigation [heart pacemaker, brain (aneurysm) clip, nerve stimulators, electrodes, ear implants, post coronary by-pass graft (epicardial pace wires), penile implants, colored contact lenses, patch to deliver medications through the skin, coiled spring intrauterine device, vascular filter for blood clots, orthodontic braces, shunt- spinal or ventricular, any metal implants (rods, joints, plates, pins, screws, nails, or clips without MR-authorization), embolization coil, or any metal fragments or shrapnel in the body].
- tendency toward claustrophobia
- severe liver disorders (plasma transaminases elevated > 3fold)
- any acute inflammatory disease within 2 weeks prior the study
- pregnancy
- nursing
- clinically relevant anemia
공부 계획
연구는 어떻게 설계됩니까?
디자인 세부사항
- 관찰 모델: 케이스 컨트롤
- 시간 관점: 유망한
코호트 및 개입
그룹/코호트 |
개입 / 치료 |
|---|---|
|
Acromegalic patients
Acromegalic patients before and after initiation of individual therapy will be investigated by 1H/31P magnetic resonance spectroscopy, thyroid sonography and oral glucose tolerance testing
|
The 31P-MRS examinations will be performed in a 7 T MR system (Siemens Healthcare, Erlangen, Germany) using a double-tuned (31P/1H) surface coil (Rapid Biomedical Ltd, Rimpar, Germany), with a diameter of 10 cm.
Participants will be investigated lying in lateral position with the right lobe of the liver positioned over the coil.
In patients without overt diabetes, glucose tolerance will be assessed by an oral glucose tolerance test, routinely performed at the outpatients clinic. The test will be performed in the morning after an overnight fast of at least 8 hours. Blood will be drawn via a catheter placed in an antecubital vein of one arm. Blood samples for the assessment of glucose, insulin, C-peptide, free fatty acids and growth hormone will be drawn at baseline as well as 30, 60, 90 and 120 minutes after ingestion of 75g glucose in a solution. Concentrations of glucose, insulin and C-peptide will be used to derive parameters of insulin secretion and insulin sensitivity by mathematical modelling.
In acromegalic patients thyroid morphology will be assessed at the outpatient clinic of the Division of Endocrinology and Metabolism, using standard ultrasound technique.
Measurements will be performed by a well- experienced physician at baseline and at each follow up examination in an out-patient care setting.
|
|
Healthy control subjects
Age and Body mass index matched control subjects will be investigated by 1H/31P magnetic resonance spectroscopy and oral glucose tolerance testing
|
The 31P-MRS examinations will be performed in a 7 T MR system (Siemens Healthcare, Erlangen, Germany) using a double-tuned (31P/1H) surface coil (Rapid Biomedical Ltd, Rimpar, Germany), with a diameter of 10 cm.
Participants will be investigated lying in lateral position with the right lobe of the liver positioned over the coil.
In patients without overt diabetes, glucose tolerance will be assessed by an oral glucose tolerance test, routinely performed at the outpatients clinic. The test will be performed in the morning after an overnight fast of at least 8 hours. Blood will be drawn via a catheter placed in an antecubital vein of one arm. Blood samples for the assessment of glucose, insulin, C-peptide, free fatty acids and growth hormone will be drawn at baseline as well as 30, 60, 90 and 120 minutes after ingestion of 75g glucose in a solution. Concentrations of glucose, insulin and C-peptide will be used to derive parameters of insulin secretion and insulin sensitivity by mathematical modelling. |
연구는 무엇을 측정합니까?
주요 결과 측정
결과 측정 |
측정값 설명 |
기간 |
|---|---|---|
|
Changes in hepatic energy metabolism
기간: before & 3,6,9, and 12 months after initiation of therapy
|
The 31P-MRS examinations will be performed in a 7 T MR system (Siemens Healthcare, Erlangen, Germany) using a double-tuned (31P/1H) surface coil (Rapid Biomedical Ltd, Rimpar, Germany), with a diameter of 10 cm.
|
before & 3,6,9, and 12 months after initiation of therapy
|
2차 결과 측정
결과 측정 |
측정값 설명 |
기간 |
|---|---|---|
|
Changes in hepatic lipid content
기간: before, as well as 3,6,9 &12 months after initiation of therapy
|
Hepatic lipid content will be assessed using localized single voxel 1H MRS as published by our study group.
STEAM sequence (VOI= 3×3×3 cm3; TE= 30, 50, 70, 120 ms; NA= 4 for each TE) data acquisition will be performed during repetitive single breath holds.
Hepatocellular lipid (HCL) content will be calculated from ration of summed area of methylene and methyl resonance to that of water following the individual spin-spin relaxation correction as per cent of total tissue MRS signal (water + methylene + methyl).
|
before, as well as 3,6,9 &12 months after initiation of therapy
|
기타 결과 측정
결과 측정 |
측정값 설명 |
기간 |
|---|---|---|
|
Changes in skeletal muscle energy metabolism
기간: before, as well as 3,6,9 and 12 months after initiation of therapy
|
Resting-state ATP turnover will be measured using a ST experiment.
The subjects will be lying in a supine position with the surface coil fixed underneath the right calf muscle.
Baseline intramyocellular concentrations of phosphorous metabolites will be assessed based on T1 corrected partially relaxed baseline spectra (TR, 15 s; 16 averages).
The exchange between γ-ATP and PCr (i.e., CK reaction), and between γ-ATP and Pi (i.e., ATP- synthesis) will be investigated.
|
before, as well as 3,6,9 and 12 months after initiation of therapy
|
|
Changes in skeletal muscle lipid content
기간: before, as well as 3,6,9 and 12 months after initiation of therapy
|
Intramyocellular lipid content will be assessed using localized single voxel 1H MRS as published by our studygroup[34].
STEAM sequence (VOI= 12x12x12 mm3; TE= 20 ms; TR= 4 sec, NA= 16) data acquisition will be performed in two volumes of interest positioned in soleus and tibialis anterior muscle.
Separate spectra without water signal suppression (NA= 4) will be obtained from both muscle groups.
Intramyocellular lipid content (IMCL) content will be calculated from ratio of area of methylene (1.25 ppm) to that of water following the individual spin-spin relaxation correction as per cent of tissue water MRS signal.
|
before, as well as 3,6,9 and 12 months after initiation of therapy
|
|
Changes in thyroid morphology
기간: before and 12 months after initiation of individual therapy
|
In acromegalic patients thyroid morphology will be assessed at the outpatient clinic of the Division of Endocrinology and Metabolism, using standard ultrasound technique.
Measurements will be performed by a well- experienced physician at baseline and at each follow up examination in an out-patient care setting.
|
before and 12 months after initiation of individual therapy
|
공동 작업자 및 조사자
수사관
- 수석 연구원: Michael Krebs, MD, Prof., Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
간행물 및 유용한 링크
연구 기록 날짜
연구 주요 날짜
연구 시작
기본 완료 (예상)
연구 완료 (예상)
연구 등록 날짜
최초 제출
QC 기준을 충족하는 최초 제출
처음 게시됨 (추정)
연구 기록 업데이트
마지막 업데이트 게시됨 (추정)
QC 기준을 충족하는 마지막 업데이트 제출
마지막으로 확인됨
추가 정보
이 정보는 변경 없이 clinicaltrials.gov 웹사이트에서 직접 가져온 것입니다. 귀하의 연구 세부 정보를 변경, 제거 또는 업데이트하도록 요청하는 경우 register@clinicaltrials.gov. 문의하십시오. 변경 사항이 clinicaltrials.gov에 구현되는 즉시 저희 웹사이트에도 자동으로 업데이트됩니다. .
1H/31P Magnetic Resonance Spectroscopy에 대한 임상 시험
-
Shanghai Ninth People's Hospital Affiliated to...모병
-
University of Wisconsin, MadisonNational Institute of Diabetes and Digestive and Kidney Diseases (NIDDK); Stanford University완전한
-
Centre hospitalier de l'Université de Montréal...Canadian Institutes of Health Research (CIHR); McGill University Health Centre/Research... 그리고 다른 협력자들모병
-
Beijing Anzhen Hospital아직 모집하지 않음다혈관 관상 동맥 질환 | ST 상승 심근 경색증(STEMI) | ACS(급성 관상동맥 증후군) | 미세혈관 폐쇄(MVO)중국
-
Memorial Sloan Kettering Cancer CenterRoyal Marsden NHS Foundation Trust; University of Pennsylvania; Columbia University; Weill... 그리고 다른 협력자들완전한육종 | 유방암 | 췌장암 | 비호지킨 림프종 | 난소 암 | 폐암 | 직장암 | 전립선암 | 뇌암 | 대장 암 | 카포시 육종 | 갑상선 암 | 신장암 | 간 암 | 편평 세포 암종 | CNS 암 | 호지킨병 | HEENT 암 | 부신피질암미국
-
University Hospital, Bordeaux완전한
-
Medical University of Vienna알려지지 않은제2형 당뇨병 | 1형 당뇨병 | 건강한 자원봉사자 | 당뇨병 전단계(인슐린 저항성, 포도당 내성 장애) | 친숙한 저칼슘성 고칼슘혈증오스트리아
-
Biotronik SE & Co. KG완전한심장병독일, 체코 공화국, 스위스, 오스트리아, 영국