Assessing the Effects of Alfacalcidol Intake on Expression of Involed Gene in Metabolism in Obese Subjects

Assessing the Effects of Supplementary Alfacalcidol Intake on Peroxisome Proliferator-activated Receptor-coactivator-1α, Vitamin D Receptor and Peroxisome Proliferator-activated Receptor Gamma Gene Expression in Obese Subjects

Obesity-induced chronic inflammation is a key component of the pathogenesis of insulin resistance. Mounting evidence has demonstrated anti-inflammatory characteristics for vitamin D. Although analogues of vitamin D3 have extensively been used in the treatment of various chronic inflammatory diseases, to our knowledge, no such research is conducted in regards with obesity. The aim of this double blind clinical trial study is to investigate whether alphacalcidol treatment in obese subjects can affect the insulin resistance. Moreover, we will evaluate the pathways of Vitamin D receptor (VDR), Peroxisome proliferator-activated receptor gamma (PPARγ) and eroxisome proliferator-activated receptor- coactivator-1 α (PGC1α) gene expressions which may lead to insulin resistance following treatment with either alphacalcidol or placebo.

Study Overview

• Status: Unknown
• Conditions: Obesity
• Intervention / Treatment: Dietary supplement: Alfacalcidol; Dietary supplement: Placebo

Detailed Description

Increasing evidence from human population studies and animal research has established correlative as well as causative links between chronic inflammation and insulin resistance. The anti-inflammatory characteristics of vitamin D have been demonstrated in previous studies. In addition to its role in bone and calcium metabolism, vitamin D is demonstrated to be influential in the regulation of different immune system functions and glucose homeostasis pathways. Although low levels of vitamin D have shown to be in close correlation with obesity, whether vitamin D deficiency is the cause or the consequence of obesity remains unclear. It is noteworthy that several studies have demonstrated that vitamin D deficiency is associated with an increased resistance to insulin.

The biologic effects of vitamin D are primarily mediated via the nuclear transcription factor, vitamin D receptor (VDR), which triggers the expression of vitamin D responsive genes. VDR is expressed on different immune cells such as monocytes, T-lymphocytes, and granulocytes. It is documented that VDR and PGC-1α show an overlapping pattern of expression. Furthermore, as the expression of PGC-1α and PPARγ are regulated via environmental stimuli such as diet, it could be suggested that the function of VDR function can also be altered in response to external stimuli. PGC-1α was demonstrated to be of a particular importance in amelioration of increased insulin sensitivity.

Accordingly, to evaluate whether alphacalcidol treatment in obese subjects who generally suffer from a low state chronic inflammation could affect the insulin resistance, we designed the current double blind clinical trial study to compare the effect of alfacalcidol with placebo on serum glucose, 25-OH vitamin D, PTH, and lipid profile levels as well as Homeostatic model assessment (HOMA) and quantitative insulin sensitivity check index (QUICKI) indexes as a markers of insulin resistance. Furthermore, to assess the possible cross talk between VDR and PPARγ, the gene expressions of these VDR, PPARγ and PGC1α were evaluated following a course of treatment with either alphacalcidol or placebo.

• Study Type: Interventional
• Enrollment (Anticipated): 94
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Arash Hossein-nezhad, MD, PhD; Email: arashh@bu.edu
• Study Contact Backup: Name: Khadijeh Mirzaei, MS; Email: mirzaei_kh@razi.tums.ac.ir

Study Locations

• Iran, Islamic Republic of
  • Tehran, Iran, Islamic Republic of
    • Recruiting
    • TehranUMS
    • Contact: Arash Hossein-nezhad, MD, PhD; Email: arashh@bu.edu
    • Contact: Khadijeh Mirzaei, MS; Email: mirzaei_kh@tums.ac.ir
    • Principal Investigator: Arash Hossein-nezhad, MD, PhD
    • Sub-Investigator: Khadijeh Mirzaei, Ms

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 22 years to 52 years (ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

Age 22-52 years Body mass index equal or more than 30

Exclusion criteria:

Acute or chronic inflammatory disease History of hypertension Alcohol or drug abuse History of any condition affecting inflammatory markers such as known cardiovascular disease Thyroid diseases Malignancies Current smoking Diabetes mellitus Sustained hypertension Heart failure Acute or chronic infections Hepatic or renal diseases Use of PPARγ agonist drug

Study Plan

How is the study designed?

Design Details

• Primary Purpose: PREVENTION
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: DOUBLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Alfacalcidol	Dietary supplement: Alfacalcidol; Alfacalcidol; Other Names: One-Alpha® Capsules 1 microgram; 1-α hydroxyvitamin D3
PLACEBO_COMPARATOR: Placebo; Corn oil pearl Capsules 1 gram: were given to the intervention group once a day for 8 weeks	Dietary supplement: Placebo; corn oil Capsules 1 gram: were given to the placebo group once a day for 8 weeks; Other Names: corn oil capsule; Corn oil Pearl

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Expression of VDR, PPARγ and PGC1α gene	measurement of Relative gene expression with RT-PCR.	Change from baseline to 8 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change of weight	measurement with Body composition device	Change from baseline to 8 weeks

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body mass index change	calculated with BMI equation	Change from baseline to 8 weeks

Collaborators and Investigators

• Sponsor: Tehran University of Medical Sciences
• Investigators: Principal Investigator: Arash Hossein-nezhad, MD, PhD, Tehran University Of Medical Sciences

Publications and helpful links

General Publications

• Mirzaei K, Hossein-Nezhad A, Keshavarz SA, Eshaghi SM, Koohdani F, Saboor-Yaraghi AA, Hosseini S, Tootee A, Djalali M. Insulin resistance via modification of PGC1alpha function identifying a possible preventive role of vitamin D analogues in chronic inflammatory state of obesity. A double blind clinical trial study. Minerva Med. 2014 Feb;105(1):63-78.

Study record dates

Study Major Dates

• Study Start: January 1, 2012
• Primary Completion (ACTUAL): December 1, 2012
• Study Completion (ANTICIPATED): January 1, 2013

Study Registration Dates

• First Submitted: December 14, 2012
• First Submitted That Met QC Criteria: December 18, 2012
• First Posted (ESTIMATE): December 19, 2012

Study Record Updates

• Last Update Posted (ESTIMATE): December 27, 2012
• Last Update Submitted That Met QC Criteria: December 24, 2012
• Last Verified: December 1, 2012

More Information

Terms related to this study

• Keywords: Obesity, vitamin D analogue, VDR, PPARg, PGC1a
• Additional Relevant MeSH Terms: Overnutrition; Nutrition Disorders; Overweight; Body Weight; Obesity; Physiological Effects of Drugs; Micronutrients; Vitamins; Bone Density Conservation Agents; Alfacalcidol; Hydroxycholecalciferols
• Other Study ID Numbers: 91-02-27-18041