Effects of Carrier Solution on Insulin Bioavailability

BACKGROUND

The aim of our study is to assess the influence of the base solution on the availability of biologic insulin expressed in the value of total insulin using the radioimmunoassay method and to monitor the influence of the base solution on the total insulin concentration over time.

METHODS

Total insulin in a saline and in a total nutrient admixture was measured using the RIA method. In 15 experiments, the application of the saline by a perfusor (8 IU Actrapid HM, 100 IU/1 mL + 20 mL saline) was carried out at time intervals of baseline, 5, 10, 30, 60, 90, and 210 minutes. The application of the total nutrient admixture (8 IU Actrapid HM + 20 mL total nutrient admixture) was carried out in the same way. The MANOVA, ANOVA and paired t test with Bonferroni correction were then used for statistical evaluation.

RESULTS

The average values of insulin concentration in saline at given time intervals were 21.5 +/- 11.3 mIU/L (5.4% of the theoretically calculated concentration). The level of insulin in the total nutrient admixture did not change over time, and it reached the values of 115.2 +/- 22.3 (28.8% of the theoretically calculated concentration). Changes in insulin concentration in time were found only in the saline (ANOVA time effect p < .001 for saline; p = .26 for total nutrient admixture).

CONCLUSIONS

The availability of insulin was significantly higher in the total nutrient admixture solution than in the saline in the 3.5-hour experiment. The dependence of insulin concentration on time is present only in saline, and the main changes in insulin bioavailability are within first 60 minutes. The difference could be caused by smaller insulin absorption to the syringe walls and to the set, owing to the amino acids in the mixture. The question whether the amino acid concentration affects insulin bioavailability stays opened to other studies.

Glycemia Influences on Glucose Metabolism in Sepsis During Hyperinsulinemic Clamp

BACKGROUND

We investigated glucose metabolism in septic patients during hyperglycemic clamps and compared the different levels of insulinemia and glycemia.

METHODS

In 10 non-diabetic stable septic patients on mechanical ventilation with baseline glycemia >6 mmol/L and continuous insulin infusion, 3 steps of hyperinsulinemic clamp were performed after 8 hours without caloric intake. In step 1, the targets were insulinemia of 250 mIU/L and glycemia of 5 mmol/L; in step 2, insulinemia of 250 mIU/L and glycemia of 10 mmol/L; in step 3, insulinemia of 1250 mIU/L and glycemia of 5 mmol/L. Glucose uptake was calculated as the amount of glucose per time needed to maintain the target level of glycemia. Glucose oxidation was calculated from indirect calorimetry and urinary nitrogen losses. Values are provided as means +/- SD. A two-way analysis of variance and Scheffe's method were used for statistical analysis and p < .05 was considered significant.

RESULTS

At step 1, glucose uptake was lower than at step 2 (3.8 +/- 2.48 mg/kg/min and 7.9 +/- 3.45 mg/kg/min, respectively; p < .001). Glucose oxidation was also lower at step 1 (2.6 +/- 0.98 and 4.2 +/- 1.85 mg/kg/min, respectively; p < .01). Glucose storage was low at step 1 (0.7 +/- 1.39) and increased at step 2 (3.5 +/- 2.18; p < .05). In step 3, glucose uptake was 7.0 +/- 2.1, oxidation was 3.6 +/- 1.37, and storage was 2.9 +/- 2.79. There was no significant difference in all these parameters between steps 2 and 3. Energy expenditure between steps 1, 2 and 3 did not change (2294 + 307.42, 2334 + 341.53, and 2342 + 426.67 kcal/day, respectively). Alanine in plasma dropped significantly (p < .05): 10 mmol/L (311 +/- 55.88 mmol/L) at glycemia compared with 5 mmol/L (390 +/- 76 micromol/L) at insulinemia 250 mIU/L. It did not differ significantly from the values obtained at glycemia 5 mmol/L and insulinemia 1250 mIU/L (348 +/- 70.68 mmol/L). Even if the level of cytokines in sepsis was higher, there was no correlation between the insulin level in plasma (250 and 1250 mIU/L), glycemia (5 and 10 mmol/L) and cytokine level (IL-1beta, IL-2, IL-6, IL-8 and TNFalpha).

CONCLUSION

At insulinemia 250 mIU/L, a glucose level of 10 mmol/L seems to increase glucose uptake, oxidation, and storage compared with glycemia 5 mmol/L. This glucose uptake and oxidation at glycemia 10 mmol/L is comparable with the effect of extremely high insulinemia (1250 mIU/L) clamped at glycemia 5 mmol/L. A higher level of blood glucose or a high level of insulinemia significantly increases glucose uptake but not energy expenditure.

Differences in skin microcirculation on the upper and lower extremities in patients with diabetes mellitus: relationship of diabetic neuropathy and skin microcirculation

INTRODUCTION

During recent years, the role of microcirculation has received increasing attention especially for its potential pathogenic role in the development of diabetes complications, particularly diabetic foot syndrome. The aim of this study was to evaluate the differences in the skin microcirculatory reactivity on the upper and lower extremities (UE and LE, respectively) in the patient with type 2 diabetes mellitus (T2DM). We also evaluated the changes in the skin microcirculation independently of the individual test for peripheral diabetic neuropathy (DN) diagnosis (Semmes-Weinstein monofilaments, Bio-Thesiometer [Bio-Medical Instrument Co., Newbury, OH], and Neuropad(®) [TRIGOcare International GmbH, Wiehl, Germany]).

PATIENTS AND METHODS

Fifty-two patients with T2DM were enrolled. Microvascular reactivity was measured by laser Doppler iontophoresis, using 1% acetylcholine chloride (ACH) and 1% sodium nitroprusside.

RESULTS

Significant reduction of perfusion was found in LE compared with UE when using ACH. In patients with DN skin microvascular reactivity on LE and UE was reduced, compared with patients without DN. Impaired skin microvascular reactivity to ACH (dominant on LE) was demonstrated in all patients who were positive in at least one of the tests for the presence of DN.

CONCLUSIONS

Reactivity of the skin microcirculation is worse on the foot than on the hand. This study confirmed a close relationship of DN and impaired skin microcirculation. It seems that autonomous neuropathy (assessed using the Neuropad) precedes the manifestation of somatosensory neuropathy.

"Mesodiencephalic" modulation in the treatment of diabetic neuropathy

OBJECTIVE

Aim of the study was to verify the efficacy of "mesodiencephalic" modulation (MDM), as named by the commercial promoters, in reducing symptoms accompanying painful diabetic neuropathy and in improving mental health.

METHODS

32 patients with type 1 and 2 diabetes mellitus, with painful neuropathy, were enrolled in the prospective, double-blind, placebo-controlled, cross-over study. The modulation was performed using MDM electrotherapeutic device (ZAT a.s), sham modulation was used as a placebo. Pain relief (visual analogue scale-VAS; total symptom score-TSS) and changes in mental state (Beck Depression Inventory-BDI-II; OSWESTRY and SF-36 questionnaires) were evaluated.

RESULTS

The study was completed by 30 patients. Pain evaluation: VAS: pain relief was statistically insignificantly higher after real (R) compared to sham (S) modulation (-0.7 vs. -0.3; p=0.06), effect of both modulations was equal after 1 month (-0.4 vs. 0.0; p=0.46). TSS: the effect of R and S modulation did not differ immediately after the procedure (-1.3 vs. -1.0; p=0.27), nor after 1 month (-1.5 vs. -0.34; p=0.9). Psychological tests: according to SF-36, the physical health improved considerably after R compared to S (2.5 vs. -2.0; p<0.01), however, changes in the mental health were equal (-1.5 vs. 0.0; p=0.78). Oswestry (0 vs. 0; p=0.95) and BDI-II (-0.5 vs. -1.0; p=0.42) were comparable after R and S modulation. Order of the procedures (R vs. S) did not affect results.

CONCLUSION

The study did not demonstrate any positive effect of MDM on painful diabetic neuropathy compared to placebo, relative to pain or mental state evaluations. The study emphasizes the need of using placebo-controlled studies, especially when testing a new analgesic drug or a method for pain modulation.

Analysis of continuous patient data from the Czech National Register of patients with type 1 and type 2 diabetes using insulin pump therapy

AIM

Patient data from the Czech National Register of patients treated with Continuous Subcutaneous Insulin Infusion (CSII) were evaluated to compare treatment indication, efficacy and safety with specific regard to the type of diabetes (T1 vs. T2).

METHODS

Evaluation was done on complete data sets of at least 3 years from patients with either T1 diabetes (n=730, 93.1%) or T2 diabetes (n=54, 6.9%) between 1995 and 2006.

RESULTS

HbA(1c) decreased from 9.65 (+/-0.07) and 9.66 (+/-0.05) for T1 and T2 respectively to 8.24 (+/-0.07) for T1 and 8.52 (+/-0.27) for T2 after 1 year of treatment, 8.34 (+/-0.07) and 8.54 (+/-0.26) after 2 years and 8.44 (+/-0.07) and 8.71 (+/-0.25) after 3 years (adjusted mean values, +/-SEM). This reduction is significant for both diabetes types. Results gathered from the safety analysis revealed almost comparable results for both patient groups (rates of adverse events of 42.5 and 34.8 for T1 and T2, per 100 patients and year).

CONCLUSION

Both patient groups achieved substantial reduction of HbA(1c). Safety evaluation showed that fewer patients with T2 diabetes were affected by adverse events. According to that CSII treatment for patients with T2 diabetes is similarly effective with a slightly better safety profile.

Change in glucometer settings as a cause of sudden deterioration of glycemic control in type 2 diabetes

The subject matter of this case report is "sudden deterioration" of glycemic control in a thus far well-complying patient with type 2 diabetes. It describes possible impacts of glucometer technical failure associated with other unfavorable circumstances. An error in displaying glycemia was discovered when analyzing data from glucometer in a computer using software (DIABASS PRO, Mediaspect GmbH, Konstanz, Germany) for data evaluation, and other possible complications (especially hypoglycemia episodes) resulting from inadequate treatment correction were thus prevented.

Influence of cardiovascular autonomic neuropathy on atherogenesis and heart function in patients with type 1 diabetes

AIM

Cardiovascular autonomic neuropathy (CAN) increases mortality of patients with type 1 diabetes (Type 1 DM). We set out to find out whether the presence of CAN in asymptomatic, normotensive Type 1 DM affects endothelial function (marker of atherogenesis) and left ventricle function (marker of cardiomyopathy).

METHODS

Twenty-one Type 1 DM with CAN (Group A) and 35 Type 1 DM without CAN (Group B) were enrolled in the study. None of them suffered from any cardiovascular disease nor advanced chronic complications of diabetes. Both groups were comparable in age, glycemic control, BMI, and blood pressure. Markers of endothelial dysfunction and chronic inflammation were used as indicators of incipient atherogenesis. Left ventricle function was evaluated using echocardiography.

RESULTS

Both groups did not differ in any parameter of atherogenesis. However we found a statistically significant difference in values characterizing systolic and diastolic left ventricle functions between the groups.

CONCLUSIONS

CAN is not associated with elevation of markers of endothelial dysfunction and chronic inflammation in normotensive asymptomatic Type 1 DM. However CAN is associated with the impairment of systolic and diastolic left ventricle function and can thus be regarded as one of the risk factors of diabetic cardiomyopathy.

Effect of mild increase of physical activity on microvasculary reactivity in obese subjects with diabetes mellitus type 2

Microangiopathy, well known in diabetic patients as a cause of late complications, develops mainly due to chronic exposition to elevated glucose and triglyceride level. Physical training acts as a protective factor even if no changes in metabolic parameters are observed. It's supposed, that lifestyle modification leads to the improvement of endothelial dysfunction and microvasculary reactivity, in healthy subjects it has already been proven experimentally.

AIM

Determine if mild, short time and metabolically indifferent increase of physical activity changes microvasculary reactivity in obese diabetic patients and how long these findings persist after return to habitual lifestyle. In 8 patients with type 2 diabetes mellitus was measured microvasculary reactivity and perfusion of skin in lower limbs by laser-doppler flowmetry and transcutaneous oximetry. First before the study, second after 3-week's period of habitual physical activity, third after 3-week's period of mild increased physical activity and finally after next 3-week's period of habitual activity. Training intensity was objectified (non sport-practiced subjects) by pedometers. Results were evaluated by Friedman and pair Wilcoxon test. After mild aerobic activity (walk about 800 [560-1400] meters/day) microvasculary reactivity was increased in both tests (increase after heating from 4,9x [4,4 D 5,4] to 6,1x [5,7 D 6,8], p<0.01, shorten half time to reach maximum perfusion from 4,1 [2,7 D 5,4] s to 3,1 [2,4 D 4,0] s, p<0.05. The increased perfusion lasted after following four weeks of habitual activity in smaller extent (microvascular reactivity increase after heating 5.2 [4.8 D 6.1] s, half time to reach maximum perfusion 3.8 [2.7 D 5.0], this increase was not significant in comparison with habitual activity in the first period). Metabolic and anthropometric parameters and transcutaneous oxygen tension didn't change significantly.

Influence of fiber on glycemic index of enteral nutrition

BACKGROUND

Enteral nutrition is indicated in patients with malnutrition due to inadequate peroral intake. A number of these patients have diabetes mellitus or impaired glucose tolerance. The aim of the study was to evaluate the influence of fiber-enriched enteral nutrition on postprandial glycemia and insulinemia.

METHODS

Ten healthy volunteers consumed the following solutions: A. 50 g of glucose, B. enteral formula containing 50 g of saccharides, and C. enteral formula containing 50 g of saccharides enriched with 2.3 g of fiber/100 mL. Postprandial glycemia and insulinemia were measured in time period after administration of specified nutrition. Time courses of glycemia and insulinemia were used for calculation of areas under the curve (AUC). The glycemic (GlyI) and insulinemic (InsI) indices of the nutrition were subsequently derived from AUC. Every measurement was performed 3 times for given type of nutrition.

RESULTS

Results are presented as median and interquartile range. GlyI of enteral nutrition was 85.76 (82.71-87.82), GlyI of enteral nutrition with fiber was 84.61 (80.31-94.39). InsI of enteral nutrition was 114.15 (106.55-137.71); InsI of enteral nutrition with fiber was 104.10 (96.71-127.96). The GlyI and InsI results did not differ significantly. Addition of fiber into enteral nutrition did not influence postprandial glycemia in comparison with common enteral nutrition.

CONCLUSIONS

Added fiber in polymerous enteral nutrition does not influence postprandial glycemia compared with polymerous enteral nutrition without fiber.

Influence of insulin on glucose metabolism and energy expenditure in septic patients

Introduction

It is recognized that administration of insulin with glucose decreases catabolic response in sepsis. The aim of the present study was to compare the effects of two levels of insulinaemia on glucose metabolism and energy expenditure in septic patients and volunteers.

Methods

Glucose uptake, oxidation and storage, and energy expenditure were measured, using indirect calorimetry, in 20 stable septic patients and 10 volunteers in a two-step hyperinsulinaemic (serum insulin levels 250 and 1250 mIU/l), euglycaemic (blood glucose concentration 5 mmol/l) clamp. Differences between steps of the clamp (from serum insulin 1250 to 250 mIU/l) for all parameters were calculated for each individual, and compared between septic patients and volunteers using the Wilcoxon nonpaired test.

Results

Differences in glucose uptake and storage were significantly less in septic patients. The differences in glucose oxidation between the groups were not statistically significant. Baseline energy expenditure was significantly higher in septic patients, and there was no significant increase in either step of the clamp in this group; when comparing the two groups, the differences between steps were significantly greater in volunteers.

Conclusion

A hyperdynamic state of sepsis leads to a decrease in glucose uptake and storage in comparison with healthy volunteers. An increase in insulinaemia leads to an increase in all parameters of glucose metabolism, but the increases in glucose uptake and storage are significantly lower in septic patients. A high level of insulinaemia in sepsis increases glucose uptake and oxidation significantly, but not energy expenditure, in comparison with volunteers.

Antibiotic treatment for uncomplicated neuropathic forefoot ulcers in diabetes: a controlled trial

To investigate the effect of oral antibiotics in purely neuropathic ulcers (Wagner grade 1-2, no osteomyelitis), a double blind placebo-controlled study was performed. Forty-four patients were enrolled and subjected to standard treatment with absolute pressure relief (half shoes), daily wound cleansing (topical disinfectant), sterile dressings (specialized nurse). Patients were randomized to an antibiotic (amoxicillin plus clavulanic acid), or placebo. The study was stopped when the antibiotic proved unsuitable according to swab result, or on clinical grounds (no improvement within 6 days of recruitment). Main outcome measure was the ulcer closing rate during 20 days, as assessed by standardized photographs. All ulcers except one were infected. Of the placebo group (n = 22), 2 patients had to be withdrawn within 6 days, versus 3 patients of the antibiotic-group (n = 22). In the placebo group, 10 ulcers were healed versus 6 ulcers in the antibiotic group (NS). Mean (95% CI) reduction in ulcer radius was 0.41 (0.21-0.61) mm day-1 in the placebo group versus 0.27 (0.15-0.39) mm day-1 in the antibiotic group (NS). In conclusion, there is no benefit from antibiotic treatment with amoxicillin plus clavulanic acid as a supplement to standard therapy in uncomplicated neuropathic foot ulcers, provided pressure relief is complete, and wound care is performed strictly supervised. However, a Type-II statistical error cannot be excluded in this small study.