Effect of Thiazolidinediones on Human Bone
Condition: Osteoblast; Adipocytes; Bone Density; Osteocalcin; Adiponectin; Mesenchymal Stem Cells
Study type: Interventional

Summary: 
      We will prospectively study 2 groups of diabetic patients treated with pioglitazone or
      placebo for 26 weeks. Bone marrow aspirates will be obtained from these patients at baseline
      and after 26 weeks of treatment, and hBMCs will be isolated from these bone marrow
      aspirations. The ability of hBMCs to differentiate into osteoblast and adipocytes lineages
      will be compared before and after treatment with pioglitazone and compared to placebo. In
      parallel, clinical markers of bone formation and resorption as well as bone mineral density
      will be assessed before and after 26 weeks of treatment. Primary endpoint for this study will
      be detection of change in number of osteoblasts or adipocytes from cultured hBMCs between
      study groups and within each group.
    

Detailed description: 
      E2a. Screening: Prescreening of electronic medical records will be used as much as possible
      to reduce screen failure rates. Patients will undergo a full history (with special focus on
      inclusion and exclusion criteria), physical exam, and blood draw. Lab work will consist of
      CBC, PT, PTT, CMP, HbA1c, PTH, serum beta-HCG in females of childbearing potential and
      testosterone in males. We will measure 25(OH) Vitamin D at baseline and completion of the
      study.

      E2b. Study visits Subjects will be admitted to the Grady GCRC after an overnight fast at the
      initial visit and at 26 weeks. Study drug will be dispensed at the initial visit. At the
      initial visit and at 26 weeks, subjects will undergo bone marrow aspiration by a skilled and
      certified Hematology Oncology fellow, bone densitometry (DXA) of their hip and spine, and a
      blood.draw (5mls).

      Subjects will be seen in follow-up at the Grady GCRC at 2 weeks and every 4 weeks thereafter
      for measurement of body weight, vital signs, and targeted history looking for any side
      effects from study drugs.

      Study drug will be dispensed to patients at baseline and on monthly follow-up visits
      thereafter. To assess compliance, subjects will be instructed to return any unused drug, and
      if the subject takes less than 75% of the study medication, the patient will be withdrawn
      from the study. Patients will be monitored closely for development of side effects. Glycemic
      control will be assessed with HbA1c measurements at baseline, 12 weeks into the study and at
      end of study. Home blood sugars, fasting and occasional postprandial blood sugars will be
      assessed at each of the study visits.

      E2b.2. Bone Marrow Biopsy aspiration: Bone marrow (BM) aspiration will be done by a
      hematology and oncology fellow, Dr. Simbo Aduloju, who is certified in doing these procedures
      at the Grady GCRC. Subjects will be pre-medicated 30 minutes prior to the procedure with oral
      Lorazepam 2mg and Tylenol 500mg for analgesia.The only absolute contraindication to BM
      aspirations is the presence of bleeding disorders. During the screening process, patients
      will be asked about a history of coagulopathies such as hemophilia. In addition all patients
      will have their PT, PTT and platelets checked at baseline. Under sterile technique and after
      local anesthesia with 2% lidocaine, 5mls of bone marrow will be aspirated from the posterior
      iliac crest using a 16 gauge bone marrow aspiration needle attached to a 10 ml syringe. The
      sample will be placed on ice immediately and transported to the lab of Dr. George Beck. After
      the procedure, manual pressure will be applied to the aspiration site for a minimum of 5
      minutes to prevent bleeding. Patients blood pressure will be checked after the procedure and
      prior to their departure from the GCRC to ensure absence of hypotension due to lorazepam.

      E2b.2.1. Please see section E2c. below for experimental design on procurement of hBMCs from
      bone marrow aspirates and determination of osteoblast/adipocyte differentiation capacity from
      these hBMCs.

      E2b.3. BMD Evaluation: DXA measurements will be performed at the spine and dominant hip
      (contralateral hip in the presence of hardware in the dominant hip) using a GE Lunar Prodigy
      Instrument (GE medical Systems) at Grady Memorial Hospital. The DXA scanner is calibrated on
      a daily basis with the manufacturer's phantom according to manufacturer guidelines.
      Short-term root mean square coefficient of variation at our center is 1.1% at the lumbar
      spine and 1.5% at the total hip.

      E2b.4. Laboratory Assays: Bone formation markers (osteocalcin, procollagen type-I N-terminal
      propeptide [P1NP]) and bone resorption markers (β C-terminal telopeptide of type 1 collagen
      [β-CTX]) correlate strongly with rates of bone formation and resorption respectively and
      provide powerful data as they reflect the average bone turnover globally across all bone
      surfaces in the body. The disadvantage of these markers is that they reflect the final state
      at the time of sampling and not conditions at any other time point in the experiment.

      After an overnight fast, serum will be assayed from subjects between 8 and 9 am to control
      for diurnal variation. Blood samples will be collected and processed by nurses at the Grady
      GCRC core laboratory. Serum will be sent to the lab of Dr. George Beck and stored at -80◦C.
      The following analyses will be done at the end of the study in a single batch for each
      marker. Please see table 2 for details of each assay.
    

Intervention name(s): Pioglitazone; Placebo
Intervention type(s): Drug; Drug
Intervention description(s): 6 month treatment with pioglitazone 15mg for four weeks with dose increased to 30mg if no adverse effects (swelling of lower extremities, liver enzyme elevation) noted at the four week mark.; The placebo pills also start out with one ("15mg") pill qday and are increased to 2 tablets ("30mg") qday after 4 weeks if no adverse effects are noted by study physician.
Other intervention name(s): Actos
Intervention MeSH terms: Pioglitazone
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Keywords: pioglitazone; human bone marrow stem cells; adipocytes; osteoblasts; bone mineral density; adiponectin; leptin; CTX; P1NP; Osteocalcin