Association of Kisspeptin Levels With Insulin Secretion in Diabetes Mellitus
Condition: Diabetes Mellitus
MeSH terms: Diabetes Mellitus
Study type: Observational

Summary: 
      Since the discovery of kisspeptin as a "gate-keeper" of hypothalamo-pituitary-gonadal axis,
      there has been tremendous interest in the molecule. The relevance of kisspeptin as regulatory
      molecule for the reproductive system has been well documented in significant number of
      trials. (1, 2) This leads to the possibility that kisspeptin could be involved in an equally
      pivotal role in the other sites, where it is located, namely pancreas.

      While various animal experiments have suggested that kisspeptins regulate insulin secretion,
      we do not know if this is also true in humans. The investigators hypothesize that kisspeptin
      levels are significantly low in individuals who have low endogenous insulin secretion.

      While various animal experiments have suggested that kisspeptins regulate insulin secretion,
      the investigators do not know if this is also true in humans. Investigators hypothesize that
      kisspeptin levels are significantly low in individuals who have low endogenous insulin
      secretion.

      Thus investigators are conducting this study to understand the link between endogenous
      insulin secretion and kisspeptin levels among individuals with various levels of insulin
      secretory defect as seen in diabetics. Investigators believe that this will help understand
      the physiologic mechanisms, and kisspeptin based insulin regulation among individuals with
      diabetes mellitus.
    

Detailed description: 
      INTRODUCTION:

      Since the discovery of kisspeptin as a "gate-keeper" of hypothalamo-pituitary-gonadal axis,
      there has been tremendous interest in the molecule. Kisspeptins are a group of peptides
      derived from the kiss gene, which share a common C-terminal decapeptide with an
      arginine-phenylalanine residue at the amino terminal.(1, 2) These peptides and their target
      receptor GPR54 are highly expressed in hypothalamus, anterior pituitary, islets of
      langerhans, and gonads. (2-5) The relevance of kisspeptin as regulatory molecule for the
      reproductive system has been well documented in significant number of trials. (6, 7) This
      leads to the possibility that kisspeptin could be involved in an equally pivotal role in the
      other sites, where it is located, namely pancreas.

      Investigators have demonstrated that kisspeptin plays a role in regulating beta cell
      activity.(8) Despite previous conflicting results suggesting glucose mediated insulin
      secretion and insulin inhibition in different studies,(9, 10) current evidence favours role
      of kisspeptin in glucose mediated insulin secretion.(11) One of earliest evidence of relation
      of insulin resistance with falling kisspeptin levels was demonstrated by Panidis et al in
      2006.

      While various animal experiments have suggested that kisspeptins regulate insulin secretion,
      we do not know if this is also true in humans. The investigators hypothesize that kisspeptin
      levels are significantly low in individuals who have low endogenous insulin secretion.

      Thus investigators plan this study to understand the link between endogenous insulin
      secretion and kisspeptin levels among individuals with various levels of insulin secretory
      defect as seen in diabetics. We believe that this will help understand the physiologic
      mechanisms, and kisspeptin based insulin regulation among individuals with diabetes mellitus.

      Researchers have also noted that the mechanism of stimulating glucose induced insulin
      release, is similar to the GLP1(Glucagon like peptide) action.(10) It would be interesting to
      ascertain a correlation between the two peptides with potentially similar action in insulin
      physiology. Leptin has been shown to alter kiss-1 expression in animal models. Establishing a
      link between leptin levels with kisspeptin in humans would help us identify further potential
      therapeutic targets involved in the multisystem manifestations of diabetes.(12)

      AIMS AND OBJECTIVES:

      1: To explore the association between levels of fasting insulin and kisspeptin levels, in
      diabetes mellitus.

      2. To explore association between Obesity and Kisspeptin levels. 3. To explore the
      association between kisspeptin and GLP-1 levels. 4. To explore the association of leptin and
      kisspeptin levels.

      RESEARCH QUESTION:

      In a population of adults attending the outpatient diabetes and medicine clinic of a tertiary
      care hospital, Do those with diabetes mellitus as compared to those without diabetes
      mellitus, have progressively lower kisspeptin levels, and is this gradient in Kisspeptin
      levels related to fasting endogenous insulin secretion. Investigators hypothesize low
      Kisspeptin levels to be associated with low insulin secretion.

      STUDY TYPE- STUDY DESIGN: Cross-sectional study Ethical approval for the trial protocol
      obtained from the institute's ethics committee of Care Hospital, Nagpur, India

      Subjects and Methods The study will be conducted in CARE Hospital, Nagpur from 1 September
      2013- 31 November 2013. Patients will be selected to enter the study, in such a way that
      every patient presenting to the diabetes and medicine clinic will be screened in the study
      and patients fulfilling inclusion criteria will be recruited in the study.

      Study population:

      Total of 60 patients will be included in the study. Investigators plan to include Diabetics
      without exogenous insulin supplementation, Diabetics with exogenous insulin supplementation
      and normal healthy cohorts, 20 in each group.

      Methods:

      The investigators will screen all patients who are referred to them after fulfilling the
      inclusion and exclusion criteria in the study. Written informed consent will be obtained from
      all participants. The patients included in the study will be administered a standardized
      questionnaire to record socio-demographic characteristics, details of diabetes management,
      history of PCOD (Polycystic Ovarian Disease), history of hypogonadism or any obvious sexual
      dysfunction drug history. A general examination for BMI (Body mass index), waist hip ratio
      and Blood pressure would be performed. Blood samples will then be withdrawn (8 ml : 2ml
      fluoride tube, 2ml EDTA (ethylenediaminetetraacetic acid ), 4 ml plain tube) after overnight
      fasting for creatinine, fasting blood glucose, fasting insulin, C-peptide levels, HbA1C
      (glycosylated haemoglobin), LH (luteinizing hormone), FSH (Follicle stimulating hormone), and
      kisspeptin levels. In female patients samples will be collected between day 3 to day 6 of a
      normal menstrual cycle. After a usual meal as regularly taken by the patient, samples (8ml:
      2ml fluoride, 4ml EDTA and 2 ml plain tube) for post-prandial blood glucose level, insulin
      level, leptin level, GLP-1 level and kisspeptin levels will be collected. The blood samples
      for creatinine, glucose (pre and post), insulin levels, HbA1C, LH and FSH will be analysed
      immediately in the laboratory. The blood samples for kisspeptin levels, GLP-1, leptin levels
      will be collected in a separate EDTA tube, centrifuged for 15 min at 4 degree and plasma will
      be stored separately in a deep freezer at -70 degree. The concentration of kisspeptin will be
      measured using Kiss¬peptin-10 (Metastin [45-54]-Amide) and competitive enzyme immunoassay
      (Kit# EK-048-56, Phoenix Pharmaceuticals, Inc., Burlingame, CA, USA). Leptin (Human) ELISA
      Kit Protocol (Cat. No.: EK-003-12, Phoenix Pharmaceuticals) will be used for serum leptin
      levels. GLP-1 (7-36)-Amide (Human,Rat, Mouse) EIA (enzymeimmunoassay) Kit (Catalog #
      EK-028-11, Phoenix Pharmaceuticals) will be used for testing GLP 1 levels. The method given
      in the product insert will be used for the assays.

      Power analyses There is no similar study done to help us predict the power of study. As the
      investigators did not have previous estimates no formal power calculation was undertaken. The
      investigators randomly decided to take 60 patients in the study, 20 in each arm.

      Data analysis All data will be entered using MS excel. Researchers will perform a descriptive
      statistical analysis of the baseline data. The analyst, who will be blinded to the laboratory
      results, will compare the outcome measure using Pearsons coefficient of correlation. All
      statistical analysis will be done using SPSS software (v.16.0 SPSS, Inc., Chicago, IL)
      Dissemination The results of this trial are expected to provide evidence and clinically
      relevant information the relation between kisspeptin and diabetes.

      Risks of participation The investigators believe there is no additional risk for the
      participants included in the study.

      Competing interests The authors declare that they have no competing interests.
    

Observational model: Case-Control
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        All patients entering medical and diabetes out patient clinics
      
Keywords: insulin, kisspeptin, GLP 1