Insulin Binding Research Articles

The diabetes-cancer link.

Type 2 diabetes is associated with increased risks for several cancers, including colon,1 postmenopausal breast,2 pancreatic,3 liver,4 endometrial,5 and bladder6 cancers and non-Hodgkins lymphoma.7 Type 2 diabetes is also linked to a modest decrease in the risk for prostate cancer.8 However, diabetes does not reduce aggressive forms, and prostate cancer mortality rates are higher among men with diabetes.9,10 Overall, increased cancer mortality associated with diabetes reflects both increased cancer incidence and decreased survival among people with diabetes who develop cancer.11–13 Research is underway examining how antihyperglycemic medications may affect cancer risk and progression. Some evidence suggests that metformin may decrease risk, and researchers are exploring whether it might even play a role in the treatment of some cancers.14,15 Normal cells develop into malignant cancer cells through a complex process, including initiation (DNA damage from a carcinogen or reactive molecule), promotion (stimulation of initiated cells' growth), and progression (more aggressive growth with angiogenesis and metastasis). Most cancers develop over at least 10–20 years. Numerous factors, including some related to metabolic states in overweight, obesity, and type 2 diabetes, as well as dietary intake and physical activity, appear to promote or inhibit cancer development.16–18 In epidemiological studies, elevated levels of insulin or C-peptide (a biomarker of insulin production) predict increased risk for colorectal, postmenopausal breast, pancreatic, bladder, and endometrial cancers.14,19 Insulin binding to its receptor activates the metabolic pathway, which stimulates glucose uptake and glycogenesis and suppresses lipolysis and liver gluconeogenesis. Although insulin resistance blocks signaling in the metabolic pathway, it does not inhibit activation of the cell-signaling pathway involving mitogen-activated protein kinase that promotes cell proliferation. Increased insulin production to overcome blockade of the metabolic pathway exaggerates activation …

Spectroscopic study of the interaction of insulin and its aptamer – sensitive optical detection of insulin

The binding of insulin to the insulin binding aptamer (IBA) was investigated with different spectroscopy techniques (UV/vis absorption, fluorescence, resonance light-scattering spectra (RLS), synchronous fluorescence, and three-dimensional fluorescence). The thermodynamic parameters (Kb, ΔH, ΔG, and ΔS) of the insulin–IBA complex were further investigated by temperature-dependent fluorescence measurement over the range of 25–37°C. The results of synchronous fluorescence, resonance light scattering (RLS) and three-dimensional fluorescence spectra showed that IBA would alter the structure of insulin. Folding of the dual-labeled insulin binding aptamer, FL-IBA, carrying 6-carboxyfluorescein (FAM) and 6-carboxytetramethylrhodamine (TAMRA) labels at termini of the insulin binding aptamer (IBA), into G-quadruplex leading to the contact quenching occurs as a result of the formation of a nonfluorescent complex between donor and acceptor. Significant fluorescent signal change when FL-IBA was bound to insulin is attributed to a conformational change in FL-IBA from a loose random coil to a compact G-quadruplex. Based on fluorescence quenching of IBA folding, a simple and sensitive insulin aptamer-based biosensor in the range of 2–70nM was proposed.

Effect of endogenous galanin on glucose transporter 4 expression in cardiac muscle of type 2 diabetic rats

Although galanin has been shown to increase glucose transporter 4 (GLUT4) expression in skeletal muscle and adipocytes of rats, there is no literature available about the effect of galanin on GLUT4 expression in cardiac muscle of type 2 diabetic rats. In this study, we investigated the relationship between intracerebroventricular administration of M35, a galanin receptor antagonist, and GLUT4 expression in cardiac muscle of type 2 diabetic rats. The rats tested were divided into four groups: rats from healthy and type 2 diabetic drug groups were injected with 2μM M35 for three weeks, while both control groups with 2μl vehicle control. The euglycemic-hyperinsulinemic clamp test was conducted for an index of glucose infusion rates. The cardiac muscle was processed for determination of GLUT4 expression levels. The present study showed that the plasma insulin and retinol binding protein 4 (RBP4) levels were higher in both drug groups than controls respectively. Moreover, the results showed the inhibitive effect of central M35 treatment on glucose infusion rates in the euglycemic-hyperinsulinemic clamp test and GLUT4 expression levels in the cardiac muscle. These results demonstrate that endogenous galanin, acting through its central receptor, has an important attribute to increase GLUT4 expression, leading to enhance insulin sensitivity and glucose uptake in cardiac muscle of type 2 diabetic rats. Galanin and its fragment can play a significant role in regulation of glucose metabolic homeostasis in cardiac muscle and galanin is an important hormone relative to diabetic heart.

Flexibility in the insulin receptor ectodomain enables docking of insulin in crystallographic conformation observed in a hormone-bound microreceptor.

Insulin binding to the insulin receptor (IR) is the first key step in initiating downstream signaling cascades for glucose homeostasis in higher organisms. The molecular details of insulin recognition by IR are not yet completely understood, but a picture of hormone/receptor interactions at one of the epitopes (Site 1) is beginning to emerge from recent structural evidence. However, insulin-bound structures of truncated IR suggest that crystallographic conformation of insulin cannot be accommodated in the full IR ectodomain due to steric overlap of insulin with the first two type III fibronectin domains (F1 and F2), which are contributed to the insulin binding-pocket by the second subunit in the IR homodimer. A conformational change in the F1-F2 pair has thus been suggested. In this work, we present an all-atom structural model of complex of insulin and the IR ectodomain, where no structural overlap of insulin with the receptor domains (F1 and F2) is observed. This structural model was arrived at by flexibly fitting parts of our earlier insulin/IR all-atom model into the simulated density maps of crystallized constructs combined with conformational sampling from apo-IR solution conformations. Importantly, our experimentally-consistent model helps rationalize yet unresolved Site 2 contacts of hormone with IR, and suggests ligand cross-linking of receptor subunits.

Mystery of Insulin Binding Revealed

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Discovery of a novel insulin-like peptide and insulin binding proteins in the Eastern rock lobster Sagmariasus verreauxi

This study reports, for the first time in any of the commercially important decapod species, the identification of an insulin-like peptide (ILP), distinct from the androgenic gland hormone. Bioinformatics analysis of the de novo assembled spiny lobster, (Sagmariasus verreauxi) transcriptome, allowed identification of Sv-ILP1 as well as eight binding proteins. Binding proteins were termed as Sv-IGFBP, due to homology with the vertebrate insulin-like growth-factor binding protein and Sv-SIBD1-7, single insulin-binding domain protein (SIBD), similar to those identified in other invertebrate species. Sv-ILP1 was found to be expressed in the eyestalk, gonads and antennal gland of both sexes and to a lesser extent in male muscle, androgenic gland and hepatopancreas. The expression profiles of each binding protein were found to vary across tissues, with Sv-SIBD5, 6 and 7 showing higher expression in the gonad, demonstrated by PCR and digital gene expression. Further spatial investigations, using in-situ hybridisation, found Sv-ILP1 to be expressed in the neurosecretory cells of the thoracic ganglia, in keeping with the tissue expression of Drosophila ILP7 (DILP7). This correlative tissue expression, considered with the phylogenetic clustering of Sv-ILP1 and DILP7, suggests Sv-ILP1 to be a DILP7 orthologue. The broad expression of Sv-ILP1 strongly suggests that ILPs have a role beyond that of masculinisation in decapods. The function of these novel peptides may have application in enhancing aquaculture practices in the commercially important decapod species.

A pharmacokinetic model of a tissue implantable insulin sensor.

While implantable sensors such as the continuous glucose monitoring system have been widely studied, both experimentally and mathematically, relatively little attention has been applied to the potential of insulin sensors. Such sensors can provide feedback control for insulin infusion systems and pumps and provide platforms for the monitoring of other biomarkers in vivo. In this work, the first pharmacokinetic model of an affinity sensor is developed for insulin operating subcutaneously in the limit of where mass transfer across biological membranes reaches a steady state. Using a physiological, compartmental model for glucose, insulin, and glucagon metabolism, the maximum sensor response and its delay time relative to plasma insulin concentration, are calculated based on sensor geometry, placement, and insulin binding parameters for a sensor localized within adipose tissue. A design relation is derived linking sensor dynamics to insulin time lag and placement within human tissue. The model should find utility in understanding dynamic insulin responses and forms the basis of model predictive control algorithms that incorporate sensor dynamics.

Central adiposity after breast cancer diagnosis is related to mortality in the Health, Eating, Activity, and Lifestyle study.

We examined whether waist circumference (WC) and waist-to-hip ratio (WHR) after breast cancer diagnosis are associated with all-cause or breast cancer-specific mortality and explored potential biological pathways mediating these relationships. Our analysis included 621 women diagnosed with local or regional breast cancer who participated in the Health, Eating, Activity, and Lifestyle study. At 30 (±4) months postdiagnosis, trained staff measured participants' waist and hip circumferences and obtained fasting serum samples for biomarker assays for assays of insulin, glucose, C-peptide, insulin growth factor-1 and binding protein-3, C-reactive protein (CRP), and adiponectin. We estimated multivariate hazard ratios (HR) and 95% confidence intervals (CI) for death over ~9.5years of follow-up. After adjustment for measured body mass index, treatment, comorbidities, race/ethnicity, diet quality, and postdiagnosis physical activity, WC was positively associated with all-cause mortality (HRq4:q1: 2.99, 95% CI 1.14, 7.86) but its positive association with breast cancer-specific mortality was not statistically significant (HRq4:q1: 2.69, 95% CI 0.69, 12.01). WHR was positively associated with all-cause mortality (HRq4:q1: 2.10, 95% CI 1.08, 4.05) and breast cancer-specific mortality (HRq4:q1: 4.02, 95% CI 1.31, 12.31). After adjustment for homeostatic model assessment (HOMA) score and C-reactive protein, risk estimates were attenuated and not statistically significant. In this diverse breast cancer survivor cohort, postdiagnosis WC and WHR were associated with all-cause mortality. Insulin resistance and inflammation may mediate the effects of central adiposity on mortality among breast cancer patients.

Estradiol Binds to Insulin and Insulin Receptor Decreasing Insulin Binding in vitro.

Rationale: Insulin (INS) resistance associated with hyperestrogenemias occurs in gestational diabetes mellitus, polycystic ovary syndrome, ovarian hyperstimulation syndrome, estrogen therapies, metabolic syndrome, and obesity. The mechanism by which INS and estrogen interact is unknown. We hypothesize that estrogen binds directly to INS and the insulin receptor (IR) producing INS resistance.Objectives: To determine the binding constants of steroid hormones to INS, the IR, and INS-like peptides derived from the IR; and to investigate the effect of estrogens on the binding of INS to its receptor.Methods: Ultraviolet spectroscopy, capillary electrophoresis, and NMR demonstrated estrogen binding to INS and its receptor. Horse-radish peroxidase-linked INS was used in an ELISA-like procedure to measure the effect of estradiol on binding of INS to its receptor.Measurements: Binding constants for estrogens to INS and the IR were determined by concentration-dependent spectral shifts. The effect of estradiol on INS binding to its receptor was determined by shifts in the INS binding curve.Main Results: Estradiol bound to INS with a Kd of 12 × 10−9 M and to the IR with a Kd of 24 × 10−9 M, while other hormones had significantly less affinity. Twenty-two nanomolars of estradiol shifted the binding curve of INS to its receptor 0.8 log units to the right.Conclusion: Estradiol concentrations in hyperestrogenemic syndromes may interfere with INS binding to its receptor producing significant INS resistance.

Human adenovirus-36 is uncommon in type 2 diabetes and is associated with increased insulin sensitivity in adults in Sweden

Background. Human adenovirus-36 (Adv36) increases adiposity, but also upregulates distal insulin signaling in vitro in human adipose and muscle tissue and in vivo in the rodent independently of adiposity. Accordingly, healthy adults and children with antibodies against Adv36 had increased insulin sensitivity and reduced hepatic lipid accumulation. We hypothesized that Adv36 infection would be less frequent in individuals with type 2 diabetes or impaired glycemic control.Methods. Presence of antibodies against Adv36 was analyzed for association to type 2 diabetes or impaired glycemic control in a two-wave population-based sample of well-characterized adults (n = 1734). Indices of impaired glycemic control included oral glucose tolerance, and circulating fasting levels of glucose, insulin, and insulin-like growth factor binding protein-1 (IGFBP-1).Results. Adv36 seropositivity was more common in those with normal glucose tolerance (NGT) than in those with diabetes (females: OR 17.2, 95% CI 4.0–74.3; males: OR 3.5, 95% CI 1.8–6.7). Also, females with NGT had higher frequency of Adv36 seropositivity than females with prediabetes (impaired glucose tolerance and/or impaired fasting glucose; OR 1.8, 95% CI 1.1–3.1). Within the female prediabetes group Adv36 seropositivity was associated with higher insulin sensitivity reflected by reduced HOMA-IR and increased IGFBP-1.Conclusion. Adv36 infection is associated with lower occurrence of type 2 diabetes and better insulin sensitivity in adults, particularly among females.

Plasma non-esterified fatty acid levels in children and their relationship with sex steroids

ObjectivePuberty is associated with decreased insulin sensitivity. Sexual hormones have been related with the onset of insulin resistance, but their relationship with non-esterified fatty acids (NEFA) remains unexplored. The aim of this study was to evaluate circulating NEFA levels in population-based samples of prepubertal children and adolescents and to analyze the association of NEFA with obesity, insulin resistance, and sexual hormones in adolescents. ExperimentalThe studied population included 854 randomly selected 6–8-year-old children and 822 children aged 12–16years. NEFA levels were determined using a commercial kit. Testosterone and estradiol levels were determined by RIA, and insulin and sex hormone binding protein by IRMA. HOMA was calculated as an indicator of insulin resistance. ResultsNEFA levels were lower in adolescents than in 6–8-year-old children, and decreased progressively with age between 12-year-olds and 16-year-olds. No significant differences in NEFA levels were observed between obese and non-obese adolescents. NEFA were not correlated with insulin or HOMA in 12–16-year-old girls, and appear negatively correlated with these variables in boys. Insulin and HOMA were negatively correlated with SHBG levels in both sexes adjusting by age but NEFA levels were not. ConclusionsNEFA levels decrease with age in adolescents and are not significantly increased in obese children, supporting the fact that the decreased insulin sensitivity at this age is not affecting NEFA metabolism. Although SHBG is related to insulin and HOMA independently of age in both sexes, SHBG levels are not associated with NEFA.

Altering O-Linked β-N-Acetylglucosamine Cycling Disrupts Mitochondrial Function

Mitochondrial impairment is commonly found in many diseases such as diabetes, cancer, and Alzheimer disease. We demonstrate that the enzymes responsible for the addition or removal of the O-GlcNAc modification, O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), respectively, are critical regulators of mitochondrial function. Using a SILAC (stable isotope labeling of amino acids in cell culture)-based proteomics screen, we quantified the changes in mitochondrial protein expression in OGT- and OGA-overexpressing cells. Strikingly, overexpression of OGT or OGA showed significant decreases in mitochondria-localized proteins involved in the respiratory chain and the tricarboxylic acid cycle. Furthermore, mitochondrial morphology was altered in these cells. Both cellular respiration and glycolysis were reduced in OGT/OGA-overexpressing cells. These data demonstrate that alterations in O-GlcNAc cycling profoundly affect energy and metabolite production.

Biologically Active Insulin-derived Peptides

Insulin has many actions within cells many of which are dependent on the cell type. For example, insulin stimulates glucose uptake in adipose tissue and skeletal muscle but not in liver. In liver glucose influx will increase as insulin stimulates the phosphorylation of glucose and eventual storage in the form of glycogen. Insulin also increases glucose oxidation, decreases glucose production, decreases lipolysis, increases protein synthesis and inhibits protein degradation in addition to others. Many actions have been related to insulin binding to its receptor and subsequent phosphorylation cascades, but insulin action on protein degradation has been shown to be linked to insulin degradation, specifically insulin degradation by the insulin-degrading enzyme (IDE). This activity has been shown to be due to an interaction of IDE with the proteasome, which is responsible for degradation of ubiquitin-tagged proteins. Smaller fragments of insulin that are produced by the action of IDE that do not bind to the insulin receptor show a small effect on protein degradation and a modest effect on mitogenesis. These small fragments do however inhibit lipolysis in a similar manner to insulin. If fragments are larger and can bind to the receptor they have been shown to increase glucose oxidation. Studies show that fragments of the insulin molecule have cellular activity, and that the varied actions of insulin are not completely controlled by insulin binding to the insulin receptor, even though the mechanisms may not be mutually exclusive.

Human biliverdin reductase‐based peptides activate and inhibit glucose uptake through direct interaction with the kinase domain of insulin receptor

Insulin binding changes conformation of the insulin receptor kinase (IRK) domain and initiates glucose uptake through the insulin, IGF-1, phosphatidyl inositol 3-kinase (PI3K), and MAPK pathways; human biliverdin reductase (hBVR) is an IRK substrate and pathway effector. This is the first report on hBVR peptide-mediated IRK activation and conformational change. (290)KYCCSRK, which increased IRK V(max) without changing K(m), stimulated glucose uptake and potentiated insulin and IGF-1 stimulation in 4 cell lines. KYCCSRK in native hBVR was necessary for the hBVR and IRK cross-activation. Peptide treatment also activated PI3K downstream effectors, Akt and ERK, phosphorylation, and Elk transcriptional activity. In cells transfected with CMV-regulated EGFP-VP-peptide plasmid, C(292)→A mutant did not stimulate glucose uptake; K(296)→A decreased uptake and kinase activity. KEDQYMKMTV, corresponding to hBVR's SH2-binding domain, was a potent inhibitor of glucose uptake and IRK. The mechanism of action of peptides was examined using cells expressing IRK (aa 988-1263) activated by coexpressed KYCCSRK. Three active cys-mutants of IRK, with fluorophore coupled to cysteines, C(1056), C(1138), or C(1234), were examined for changes in fluorescence emission spectra in the presence of peptides. KYCCSRK and KEDQYMKMTV bound to different sites in IRK. The findings identify novel agents for activating or inhibiting insulin signaling and offer a new approach for treatment of type 2 diabetes and hypoglycemia.

Activated α2-Macroglobulin Binding to Cell Surface GRP78 Induces T-Loop Phosphorylation of Akt1 by PDK1 in Association with Raptor

PDK1 phosphorylates multiple substrates including Akt by PIP3-dependent mechanisms. In this report we provide evidence that in prostate cancer cells stimulated with activated α2-macroglobulin (α2M*) PDK1 phosphorylates Akt in the T-loop at Thr308 by using Raptor in the mTORC1 complex as a scaffold protein. First we demonstrate that PDK1, Raptor, and mTOR co-immunoprecipitate. Silencing the expression, not only of PDK1, but also Raptor by RNAi nearly abolished Akt phosphorylation at AktThr308 in Raptor-immunoprecipitates of α2M*-stimulated prostate cancer cells. Immunodepleting Raptor or PDK from cell lysates of cells treated with α2M* drastically reduced Akt phosphorylation at Thr308, which was recovered by adding the supernatant of Raptor- or PDK1-depleted cell lysates, respectively. Studies of insulin binding to its receptor on prostate cancer cells yielded similar results. We thus demonstrate that phosphorylating the T-loop Akt residue Thr308 by PDK1 requires Raptor of the mTORC1 complex as a platform or scaffold protein.

An Isothermal Titration and Differential Scanning Calorimetry Study of the G-Quadruplex DNA–Insulin Interaction

The binding of insulin to the G-quadruplexes formed by the consensus sequence of the insulin-linked polymorphic region (ILPR) was investigated with differential scanning calorimetry (DSC) and isothermal titration calorimetry (ITC). The thermal denaturation temperature of insulin was increased by almost 4 °C upon binding to ILPR G-quadruplex DNA as determined by DSC. The thermodynamic parameters (K(D), ΔH, ΔG, and ΔS) of the insulin-G-quadruplex complex were further investigated by temperature-dependent ITC measurement over the range of 10-37 °C. The binding of insulin to the ILPR consensus sequence displays micromolar affinity in phosphate buffer at pH 7.4, which is mainly driven by entropic factors below 25 °C but by enthalpic terms above 30 °C. The interaction was also examined in several different buffers, and results showed that the observed ΔH is dependent on the ionization enthalpy of the buffer used. This indicates proton release upon the binding of G-quadruplex DNA to insulin. Additionally, the large negative change in heat capacity for this interaction may be associated with the dominant hydrophobicity of the amino acid sequence of insulin's β subunit, which is known to bind to the ILPR G-quadruplex DNA.

Lowered extracellular pH is involved in the pathogenesis of skeletal muscle insulin resistance

Insulin resistance in the skeletal muscle is manifested by diminished insulin-stimulated glucose uptake and is a core factor in the pathogenesis of type 2 diabetes mellitus (DM), but the mechanism causing insulin resistance is still unknown. Our recent study has shown that pH of interstitial fluids was lowered in early developmental stage of insulin resistance in OLETF rats, a model of type 2 DM. Therefore, in the present study, we confirmed effects of the extracellular pH on the insulin signaling pathway in a rat skeletal muscle-derived cell line, L6 cell. The phosphorylation level (activation) of the insulin receptor was significantly diminished in low pH media. The phosphorylation level of Akt, which is a downstream target of the insulin signaling pathway, also decreased in low pH media. Moreover, the insulin binding to its receptor was reduced by lowering extracellular pH, while the expression of insulin receptors on the plasma membrane was not affected by the extracellular pH. Finally, insulin-stimulated 2-deoxyglucose uptake in L6 cells was diminished in low pH media. Our present study suggests that lowered extracellular pH conditions may produce the pathogenesis of insulin resistance in skeletal muscle cells.

Media-dependent morphology of supramolecular aggregates of β-cyclodextrin-grafted chitosan and insulin through multivalent interactions.

A supramolecular protein-binding system based on multivalent interactions was investigated using β-cyclodextrin-grafted chitosan (BCC) and insulin. 1H NMR and fluorescence analyses revealed that BCC binds to insulin through electrostatic and host-guest interactions. The binding constant KBCC for the host-guest interaction between cyclodextrin (CyD) residues in BCC and Tyr and Phe residues in insulin was 478.7 M-1 in acetate buffer at pH 3.6, which was ca. 3-fold greater than the Kchi attributed to electrostatic interactions between chitosan and the Tyr residues of insulin. Furthermore, KBCC was ∼10 times greater than that of β-CyD (KCyD), suggesting that multivalent interactions composed of electrostatic and host-guest interactions strongly enhance the host-guest interaction, similar to enzymes and antibodies in living systems. Enhanced host-guest interactions resulted in effective insulin binding over a wide pH range (3.6-7.4) as well as stabilization against digestive enzymes. BCC and insulin formed supramolecular aggregates with significantly different morphologies depending on the buffer species used: a network structure in acetate buffer, nanoparticles in citrate buffer, and large aggregates in phosphate buffer. The network structure formed in acetate buffer was maintained even after dilution with phosphate buffer, a situation that mimics the environment after oral administration. In addition, the structure was fragmented easily after application of a mild force, which could be an important property for achieving absorption of protein-peptide drugs from the gastrointestinal tract. This study provides new insights for the development of CyD-based nanoarchitectures suitable for application as protein-peptide carriers for oral drug delivery.

Decreased gene expressions of insulin signal molecules in canine hyperadrenocorticism.

ABSTRACTHyperadrenocorticism (HAC) is a common endocrine disorder in dogs, in which excess glucocorticoid causes insulin resistance. Disturbance of insulin action may be caused by multiple factors, including transcriptional modulation of insulin signal molecules which lie downstream of insulin binding to insulin receptors. In this study, gene expressions of insulin signal molecules were examined using neutrophils of the HAC dogs (the untreated dogs and the dogs which had been treated with trilostane). Insulin receptor substrate (IRS)-1, IRS-2, phosphatidylinositol 3-kinase (PI3-K), protein kinase B/Akt kinase (Akt)-2 and protein kinase C (PKC)-lambda were analyzed in the HAC dogs and compared with those from normal dogs. The IRS-1 gene expressions decreased by 37% and 35% of the control dogs in the untreated and treated groups, respectively. The IRS-2 gene expressions decreased by 61% and 72%, the PI3-K gene expressions decreased by 47% and 55%, and the Akt-2 gene expressions decreased by 45% and 56% of the control dogs, similarly. Collectively, gene expressions of insulin signal molecules are suppressed in the HAC dogs, which may partially contribute to the induction of insulin resistance.

INSULIN RESISTANCE IN COWS DURING DRY PERIOD AND EARLY LACTATION

SUMMARY: Insulin resistance is pathophisiological term defined as change in insulin responsiveness (insulin response to glucose) or insulin sensitivity (tissue response to insulin) or both. The aim of this study was to investigate insulin resistance in dairy cows during dry period and early lactation, and determine influence of insulin, glucose and NEFA to RQUICKI index of insulin resistance. Cows in early lactation showed lower concentration of glucose and insulin and higher concentration of NEFA compared to cows in dry period. Insulin:glucose index are 2.5 in dry period and 2.05 in early lactation. RQUICKI index was lower during early lactation. Determination of RQUICKI value using a concentration of glucose, insulin and NEFA was correct in 78.9% in dry period and 84.5% in early lactation. During dry period insulin and glucose showed significant influence to RQUICKI value (negative correlation), but there was found absence of NEFA influences. However, NEFA only showed significant influences to RQUICKI in early lactation (negative correlation). Insulin and glucose determined RQUICKI in 56% from 78.9% of whole model, but in early lactation NEFA determined 32% from 84.5%. Higher glucose concentration means higher insulin response in dry period with consequently poor insulin binding and glucose transport. In this condition it is need higher concentration of insulin to neutralize same concentration of glucose. Therefore, found higher insulin:glucose ration was found in dry period in relation to early lactation. Insulin resistance is more intense in early lactation compared to dry period. Based on metabolic change insulin resistance in dry period is consequence of decreased insulin sensitivity of peripheral tissue with compensatory increased insulin:glucose ration. During early lactation there is decrease insulin and glucose concentration with lower insulin response to glucose. Absence of insulin increases lipid mobilization which determined insulin resistance level.