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

NCT ID: NCT01752244

Last Updated: 2012-12-27

Basic Information

• Recruitment Status: UNKNOWN
• Clinical Phase: NA
• Total Enrollment: 94 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2012-01-31
• Study Completion Date: 2013-01-31

Brief Summary

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.

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.

Conditions

Obesity

Keywords

Obesity, vitamin D analogue, VDR, PPARg, PGC1a

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: PREVENTION
• Blinding Strategy: DOUBLE

Study Groups

Alfacalcidol

Alfacalcidol

Group Type: EXPERIMENTAL

Alfacalcidol

Intervention Type: DIETARY_SUPPLEMENT

Alfacalcidol

Placebo

Corn oil pearl Capsules 1 gram: were given to the intervention group once a day for 8 weeks

Group Type: PLACEBO_COMPARATOR

Placebo

Intervention Type: DIETARY_SUPPLEMENT

corn oil Capsules 1 gram: were given to the placebo group once a day for 8 weeks

Interventions

Placebo

corn oil Capsules 1 gram: were given to the placebo group once a day for 8 weeks

Intervention Type: DIETARY_SUPPLEMENT

Alfacalcidol

Alfacalcidol

Intervention Type: DIETARY_SUPPLEMENT

Other Intervention Names

corn oil capsule; Corn oil Pearl; One-Alpha® Capsules 1 microgram; 1-α hydroxyvitamin D3

Eligibility Criteria

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

• Minimum Eligible Age: 22 Years
• Maximum Eligible Age: 52 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Tehran University of Medical Sciences

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Arash Hossein-nezhad, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Tehran University of Medical Sciences

Khadijeh Mirzaei, Ms

Role: PRINCIPAL_INVESTIGATOR

Tehran University of Medical Sciences

Locations

TehranUMS

Tehran, , Iran

Site Status: RECRUITING

Countries

Iran

Central Contacts

Arash Hossein-nezhad, MD, PHD

Role: CONTACT

Email: arashh@bu.edu

Khadijeh Mirzaei, MS

Role: CONTACT

Email: mirzaei_kh@razi.tums.ac.ir

Facility Contacts

Arash Hossein-nezhad, MD, PhD

Role: primary

Khadijeh Mirzaei, MS

Role: backup

References

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.

Reference Type: DERIVED

PMID: 24572452 (View on PubMed)

Other Identifiers

91-02-27-18041

Identifier Type: -

Identifier Source: org_study_id