A ketone monoester drink reduces postprandial blood glucose concentrations in adults with type 2 diabetes: a randomised controlled trial

AIMS/HYPOTHESIS

The aim of the present study was to conduct a randomised, placebo-controlled, double-blind, crossover trial to determine whether pre-meal ketone monoester ingestion reduces postprandial glucose concentrations in individuals with type 2 diabetes.

METHODS

In this double-blind, placebo-controlled, crossover design study, ten participants with type 2 diabetes (age 59±1.7 years, 50% female, BMI 32±1 kg/m2, HbA1c 54±2 mmol/mol [7.1±0.2%]) were randomised using computer-generated random numbers. The study took place at the Nutritional Physiology Research Unit, University of Exeter, Exeter, UK. Using a dual-glucose tracer approach, we assessed glucose kinetics after the ingestion of a 0.5 g/kg body mass ketone monoester (KME) or a taste-matched non-caloric placebo before a mixed-meal tolerance test. The primary outcome measure was endogenous glucose production. Secondary outcome measures were total glucose appearance rate and exogenous glucose appearance rate, glucose disappearance rate, blood glucose, serum insulin, β-OHB and NEFA levels, and energy expenditure.

RESULTS

Data for all ten participants were analysed. KME ingestion increased mean ± SEM plasma beta-hydroxybutyrate from 0.3±0.03 mmol/l to a peak of 4.3±1.2 mmol/l while reducing 2 h postprandial glucose concentrations by ~18% and 4 h postprandial glucose concentrations by ~12%, predominately as a result of a 28% decrease in the 2 h rate of glucose appearance following meal ingestion (all p<0.05). The reduction in blood glucose concentrations was associated with suppressed plasma NEFA concentrations after KME ingestion, with no difference in plasma insulin concentrations between the control and KME conditions. Postprandial endogenous glucose production was unaffected by KME ingestion (mean ± SEM 0.76±0.15 and 0.88±0.10 mg kg-1 min-1 for the control and KME, respectively). No adverse effects of KME ingestion were observed.

CONCLUSIONS/INTERPRETATION

KME ingestion appears to delay glucose absorption in adults with type 2 diabetes, thereby reducing postprandial glucose concentrations. Future work to explore the therapeutic potential of KME supplementation in type 2 diabetes is warranted.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05518448.

FUNDING

This project was supported by a Canadian Institutes of Health Research (CIHR) Project Grant (PJT-169116) and a Natural Sciences and Engineering Research Council (NSERC) Discovery Grant (RGPIN-2019-05204) awarded to JPL and an Exeter-UBCO Sports Health Science Fund Project Grant awarded to FBS and JPL.

Update on Measuring Ketones

Ketone bodies are an energy substrate produced by the liver and used during states of low carbohydrate availability, such as fasting or prolonged exercise. High ketone concentrations can be present with insulin insufficiency and are a key finding in diabetic ketoacidosis (DKA). During states of insulin deficiency, lipolysis increases and a flood of circulating free fatty acids is converted in the liver into ketone bodies-mainly beta-hydroxybutyrate and acetoacetate. During DKA, beta-hydroxybutyrate is the predominant ketone in blood. As DKA resolves, beta-hydroxybutyrate is oxidized to acetoacetate, which is the predominant ketone in the urine. Because of this lag, a urine ketone test might be increasing even as DKA is resolving. Point-of-care tests are available for self-testing of blood ketones and urine ketones through measurement of beta-hydroxybutyrate and acetoacetate and are cleared by the US Food and Drug Administration (FDA). Acetone forms through spontaneous decarboxylation of acetoacetate and can be measured in exhaled breath, but currently no device is FDA-cleared for this purpose. Recently, technology has been announced for measuring beta-hydroxybutyrate in interstitial fluid. Measurement of ketones can be helpful to assess compliance with low carbohydrate diets; assessment of acidosis associated with alcohol use, in conjunction with SGLT2 inhibitors and immune checkpoint inhibitor therapy, both of which can increase the risk of DKA; and to identify DKA due to insulin deficiency. This article reviews the challenges and shortcomings of ketone testing in diabetes treatment and summarizes emerging trends in the measurement of ketones in the blood, urine, breath, and interstitial fluid.

A retrospective analysis of the incidence, outcome and factors associated with the occurrence of euglycemic ketoacidosis in diabetic patients on sodium glucose co-transporter - 2 inhibitors undergoing cardiac surgery

Introduction

SGLT2i is a new class of drugs used for type 2 diabetes. SGLT2i are known to cause EuKA in the perioperative period. Euglycemic ketoacidosis (EuKA) can cause life-threatening metabolic acidosis in the perioperative setting. Though the event rate of SGLT2i associated diabetic ketoacidosis in nonoperative setting is low, incidence among peri-operative patients can be very high and remains unknown.

Aim

The aim of this study was to find the incidence, analyze outcome, and establish correlation between risk factors and EuKA in cardiac surgical patients on SGLT2i.

Materials and Methods

This is a retrospective study analyzing 24 cardiac surgical patients who were on SGLT2i for type 2 diabetes mellitus. Data collection included age, sex, BMI, preoperative HbA1C, albumin, creatinine, type of SGLT2i and timing of stopping before surgery, insulin administration in the immediate pre-operative period; use of CPB, GI infusion and inotropes in the intraoperative period; blood ketone, duration of ventilation, hydration status and length of postoperative stay in postoperative period. Patients were diagnosed to have EuKA if any one of the serially measured postoperative ketone values was more than 0.6 mmol/L (ketone positive). The collected data were used to find an association between the risk factors and the occurrence of EuKA.

Results

Of the 24 patients, 17 patients developed EuKA. (70.8.%). 10 of the 17 EuKA in our study required preoperative Insulin for diabetic control whereas none in the ketone negative patients required insulin. This was statistically significant (P = 0.019). Association of other factors to EuKA were not statistically significant.

Conclusion

Though the event rate of SGLT2i associated Diabetic ketoacidosis in nonoperative setting is low, (17), the occurrence of EUKA in cardiac surgical patients on SGLT2i in our study was 70.8% (17 out of 24 patients). Patients who require insulin in addition to other oral hypoglycemic drugs for immediate preoperative glycemic control are at risk for the development of SGLT2 inhibitor-induced EuKA postoperatively. Missing the diagnosis of EuKA is fatal in these patients. We couldn't make a diagnosis in our first patient whom we lost. Since it was diagnosed in all our study patients by measuring serial ketone values, there was no mortality and insignificant morbidity. Cessation of SGLT2i before surgery, expectant watch for blood ketones, and treatment with GI infusion reduce morbidity and mortality in cardiac surgical patients.

Correlation between ketones and mental fatigue in high fat-induced obese and non-obese rats

Obesity, often caused by a diet high in calories and low physical activity, may induce physical fatigue, as experienced via decreased locomotor activity and mental fatigue such as impaired cognition. This study aims to evaluate glucose and ketone levels secondary to high-fat diet (HFD) exposure and signs of physical and mental fatigue. Fifty-four 7-week-old male Sprague Dawley rats (Rattus norvegicus) were assigned to either an HFD (n = 28) or a standard diet (SD; n = 26) for a 6-week period during which body weight, blood glucose, and ketones were measured twice per week. An open field (OF) paradigm was used to measure locomotor activity, while novel object recognition (NOR) test was used as an indicator of cognition. Animals in the HFD group weighed more than SD rats (8.4 g; p < 0.05) starting at Day 11, blood glucose levels were higher in the HFD group versus SD rats (3.9 mg/dl; p < 0.05) beginning in Week 5, and ketones were lower for the HFD versus the SD group throughout the study (0.34 mmol/L on average; p < 0.05). Although there was no significant difference in locomotor activity between the HFD and SD groups (p = 0.12), regardless of diet, higher ketone levels were associated with increased NOR time and ratio between the familiar and novel objects (p < 0.01). Thus, this study provides evidence that an increased level of ketones is associated with greater cognitive performance and a lesser probability of experiencing mental fatigue.

Beneficial Effects of Exogenous Ketogenic Supplements on Aging Processes and Age-Related Neurodegenerative Diseases

Life expectancy of humans has increased continuously up to the present days, but their health status (healthspan) was not enhanced by similar extent. To decrease enormous medical, economical and psychological burden that arise from this discrepancy, improvement of healthspan is needed that leads to delaying both aging processes and development of age-related diseases, thereby extending lifespan. Thus, development of new therapeutic tools to alleviate aging processes and related diseases and to increase life expectancy is a topic of increasing interest. It is widely accepted that ketosis (increased blood ketone body levels, e.g., β-hydroxybutyrate) can generate neuroprotective effects. Ketosis-evoked neuroprotective effects may lead to improvement in health status and delay both aging and the development of related diseases through improving mitochondrial function, antioxidant and anti-inflammatory effects, histone and non-histone acetylation, β-hydroxybutyrylation of histones, modulation of neurotransmitter systems and RNA functions. Administration of exogenous ketogenic supplements was proven to be an effective method to induce and maintain a healthy state of nutritional ketosis. Consequently, exogenous ketogenic supplements, such as ketone salts and ketone esters, may mitigate aging processes, delay the onset of age-associated diseases and extend lifespan through ketosis. The aim of this review is to summarize the main hallmarks of aging processes and certain signaling pathways in association with (putative) beneficial influences of exogenous ketogenic supplements-evoked ketosis on lifespan, aging processes, the most common age-related neurodegenerative diseases (Alzheimer’s disease, Parkinson’s disease and amyotrophic lateral sclerosis), as well as impaired learning and memory functions.

Exogenous Ketosis Impairs 30-min Time-Trial Performance Independent of Bicarbonate Supplementation

PURPOSE

We recently demonstrated that coingestion of NaHCO3 to counteract ketoacidosis resulting from oral ketone ester (KE) intake improves mean power output during a 15-min time trial (TT) at the end of a 3-h cycling race by ~5%. This ergogenic effect occurred at a time when blood ketone levels were low, as ketosis was only induced during the initial ~2 h of the race. Therefore, in the current study, we investigated whether performance also increases if blood ketone levels are increased in the absence of ketoacidosis during high-intensity exercise.

METHODS

In a double-blind crossover design, 14 well-trained male cyclists completed a 30-min TT (TT30') followed by an all-out sprint at 175% of lactate threshold (SPRINT). Subjects were randomized to receive (i) 50 g KE, (ii) 180 mg·kg-1 body weight NaHCO3 (BIC), (iii) KE + BIC, or (iv) a control drink (CON).

RESULTS

KE ingestion increased blood d-ß-hydroxybutyrate to ~3-4 mM during the TT30' and SPRINT (P < 0.001 vs CON). In KE, blood pH and bicarbonate concomitantly dropped, causing 0.05 units lower pH and 2.6 mM lower bicarbonate in KE compared with CON during the TT30' and SPRINT (P < 0.001 vs CON). BIC coingestion resulted in 0.9 mM higher blood d-ß-hydroxybutyrate (P < 0.001 vs KE) and completely counteracted ketoacidosis during exercise (P > 0.05 vs CON). Mean power output during TT30' was similar between CON and BIC at 281 W, but was 1.5% lower in the KE conditions (main effect of KE: P = 0.03). Time to exhaustion in the SPRINT was ~64 s in CON and KE and increased by ~8% in the BIC conditions (main effect of BIC: P < 0.01).

DISCUSSION

Neutralization of acid-base disturbance by BIC coingestion is insufficient to counteract the slightly negative effect of KE intake during high-intensity exercise.

An Intermittent Fasting Mimicking Nutrition Bar Extends Physiologic Ketosis in Time Restricted Eating: A Randomized, Controlled, Parallel-Arm Study

There has been increasing interest in time-restricted eating to attain intermittent fasting's metabolic benefits. However, a more extended daily fast poses many challenges. This study was designed to evaluate the effects of a 200-calorie fasting-mimicking diet (FMD) energy bar formulated to prolong ketogenesis and mitigate fasting-associated side effects. A randomized, controlled study was conducted comparing the impact of consuming an FMD bar vs. continued water fast, after a 15-h overnight fast. Subjects in the FMD group showed a 3-h postprandial beta-hydroxybutyrate (BHB) level and 4-h postprandial BHB area under the curve (AUC0-4) that were non-inferior to those who continued with the water fast (p = 0.891 and p = 0.377, respectively). The postprandial glucose AUC0-4 in the FMD group was non-inferior to that in the water fast group (p = 0.899). A breakfast group served as a control, which confirmed that the instrument used in home glucose and ketone monitoring functioned as expected. The results indicate that FMD bar consumption does not interfere with the physiological ketogenesis associated with overnight fasting and could be used to facilitate the practice of time-restricted eating or intermittent fasting.

The Effect of Blood Ketone Concentration and Exercise Intensity on Exogenous Ketone Oxidation Rates in Athletes

INTRODUCTION

Exogenous ketones potentially provide an alternative, energetically advantageous fuel to power exercising skeletal muscle. However, there is limited evidence regarding their relative contribution to energy expenditure during exercise. Furthermore, the effect of blood ketone concentration and exercise intensity on exogenous ketone oxidation rates is unknown.

METHODS

Six athletes completed cycling ergometer exercise on three occasions within a single-blind, random-order controlled, crossover design study. Exercise duration was 60 min, consisting of 20-min intervals at 25%, 50%, and 75% maximal power output (WMax). Participants consumed (i) bitter flavored water (control), (ii) a low-dose β-hydroxybutyrate (βHB) ketone monoester (KME; 252 mg·kg BW-1, "low ketosis"), or (iii) a high-dose βHB KME (752 mg·kg BW-1, "high ketosis"). The KME contained a 13C isotope label, allowing for the determination of whole-body exogenous βHB oxidation rates through sampled respiratory gases.

RESULTS

Despite an approximate doubling of blood βHB concentrations between low- and high-ketosis conditions (~2 mM vs ~4.4 mM), exogenous βHB oxidation rates were similar at rest and throughout exercise. The contribution of exogenous βHB oxidation to energy expenditure peaked during the 25% WMax exercise intensity but was relatively low (4.46% ± 2.71%). Delta efficiency during cycling exercise was significantly greater in the low-ketosis (25.9% ± 2.1%) versus control condition (24.1% ± 1.9%; P = 0.027).

CONCLUSIONS

Regardless of exercise intensity, exogenous βHB oxidation contributes minimally to energy expenditure and is not increased by elevating circulating concentrations greater than ~2 mM. Despite low exogenous βHB oxidation rates, exercise efficiency was significantly improved when blood βHB concentration was raised to ~2 mM.

The effect of ketogenic diets on neurogenesis and apoptosis in the dentate gyrus of the male rat hippocampus

Ketogenic diets (KD) have become popular diet to lose weight. However, the effect of such diets on brain function has not yet been clarified. Thus, we aimed to study the effects of KD on the neurogenesis and apoptosis in the dentate gyrus by assessing the expression of Ki-67 and Caspase-3. Rats (n = 24) were divided into four groups: control (normal diet), ketogenic diet (KD), time-restricted diet (TRD), and the combination of high-fat and time-restricted diet (CD) groups. The expression of Ki-67 in the TRD and CD groups was higher compared to others (P < 0.05), whereas no such difference was observed in the KD group. The number of Capase-3-positive cells decreased significantly in the TRD group (P < 0.05), but such decrease was not observed in the CD group. These results indicate that, although KD could be effective in reducing the body weight, possible adverse effect in the brain cannot be ignored.

Reliability and diagnostic performance of a new blood ketone and glucose meter in humans

BACKGROUND

Accurate and reliable monitoring of blood ketone and glucose levels is useful for athletes adhering to a ketogenic diet who want to verify that they are in a state of ketosis and, therefore, accruing performance adaptations. However, the cost of devices and testing materials may prohibit their use. More affordable field testing systems are available, but their accuracy and reliability remain in question. The objectives of this study were to evaluate the agreement between a previously validated ketone and glucose meter (Meter 1 - Precision Xtra) and a more affordable meter that has not been validated (Meter 2 - Keto-Mojo), and also to assess the diagnostic performance of Meter 2 for identifying nutritional ketosis.

METHODS

Thirteen participants (7 females and 6 males; 21.6 ± 3.0 years old) visited the laboratory three times in this randomized, double-blind cross-over design study. Ketone and glucose levels were measured with Meter 1 and Meter 2 twice before and twice after ingestion of a racemic ketone, natural ketone, or maltodextrin supplement. Intraclass correlation coefficient (ICC) estimates and their 95% confidence intervals were calculated to evaluate interrater reliability for Meter 1 and Meter 2. Bland-Altman plots were constructed to visually assess the agreement between devices. Area under the ROC curve analysis was performed to evaluate the diagnostic ability of Meter 2 to detect nutritional ketosis at a threshold ketone level of 0.5 mM as identified by Meter 1.

RESULTS

Reliability between the meters was excellent for measuring ketones (ICC = .968; .942-.981) and good for measuring glucose (ICC = .809; .642-.893), though the Bland-Altman plot revealed substantial differences in agreement for measuring glucose. Area under the ROC curve (Area = 0.913; 0.828-0.998) was excellent for diagnosing nutritional ketosis.

CONCLUSIONS

Both Meter 1 and Meter 2 displayed excellent agreement between each other for ketone measurement. Meter 2 also displayed an excellent level of accuracy for diagnosing nutritional ketosis at a threshold value of 0.5 mM, making it an effective and affordable alternative to more expensive testing devices.

Effect of Atorvastatin on blood ketone levels and glycemic control in patients with type 2 diabetes mellitus: A single arm pilot study

BACKGROUND AND AIMS

Cholesterol and ketone bodies are synthesized in liver from a common precursor acetyl coenzyme A (acetyl-CoA). Statins by inhibiting cholesterol synthesis may lead to accumulation of acetyl-CoA in hepatocytes and its diversion towards ketogenesis. Ketone bodies may act as alternative energy source thus sparing blood glucose and contributing to hyperglycemia. The present study aims to assess the effect of Atorvastatin therapy on blood ketone levels and glycemic control in patients with T2DM.

METHODS

Study included 24 statin naïve subjects with T2DM. They were prescribed tablet Atorvastatin at dose of 10 mg once daily at bedtime. Ongoing anti-diabetic medications were not changed. Estimation of blood ketones, urine ketones, fasting plasma glucose (FPG), post-prandial plasma glucose (PPG), glycated hemoglobin (HbA1c) and lipid parameters was carried out at baseline and at 3 months after starting Atorvastatin.

RESULTS

There was moderate but significant increase in blood ketones (0.16 ± 0.08 mmol/L vs. 0.26 ± 0.07 mmol/L; p-value = 0.0000), FPG (133.8 ± 17.91 mg/dL vs. 143.3 ± 22.99 mg/dL; p-value = 0.0016) and PPG (193.0 ± 36.54 mg/dL vs. 211.0 ± 49.51 mg/dL; p-value = 0.0344) after 3 months of Atorvastatin therapy. This was associated with significant reduction in serum total cholesterol and low density lipoprotein cholesterol.

CONCLUSION

Three months therapy with Atorvastatin at the dose of 10 mg once daily at bedtime in patients with T2DM resulted in moderate rise in blood ketone levels, FPG and PPG in addition to improvement in lipid parameters.

Relationships between hyperinsulinaemia, magnesium, vitamin D, thrombosis and COVID-19: rationale for clinical management

Risk factors for COVID-19 patients with poorer outcomes include pre-existing conditions: obesity, type 2 diabetes mellitus, cardiovascular disease (CVD), heart failure, hypertension, low oxygen saturation capacity, cancer, elevated: ferritin, C reactive protein (CRP) and D-dimer. A common denominator, hyperinsulinaemia, provides a plausible mechanism of action, underlying CVD, hypertension and strokes, all conditions typified with thrombi. The underlying science provides a theoretical management algorithm for the frontline practitioners.Vitamin D activation requires magnesium. Hyperinsulinaemia promotes: magnesium depletion via increased renal excretion, reduced intracellular levels, lowers vitamin D status via sequestration into adipocytes and hydroxylation activation inhibition. Hyperinsulinaemia mediates thrombi development via: fibrinolysis inhibition, anticoagulation production dysregulation, increasing reactive oxygen species, decreased antioxidant capacity via nicotinamide adenine dinucleotide depletion, haem oxidation and catabolism, producing carbon monoxide, increasing deep vein thrombosis risk and pulmonary emboli. Increased haem-synthesis demand upregulates carbon dioxide production, decreasing oxygen saturation capacity. Hyperinsulinaemia decreases cholesterol sulfurylation to cholesterol sulfate, as low vitamin D regulation due to magnesium depletion and/or vitamin D sequestration and/or diminished activation capacity decreases sulfotransferase enzyme SULT2B1b activity, consequently decreasing plasma membrane negative charge between red blood cells, platelets and endothelial cells, thus increasing agglutination and thrombosis.Patients with COVID-19 admitted with hyperglycaemia and/or hyperinsulinaemia should be placed on a restricted refined carbohydrate diet, with limited use of intravenous dextrose solutions. Degree/level of restriction is determined by serial testing of blood glucose, insulin and ketones. Supplemental magnesium, vitamin D and zinc should be administered. By implementing refined carbohydrate restriction, three primary risk factors, hyperinsulinaemia, hyperglycaemia and hypertension, that increase inflammation, coagulation and thrombosis risk are rapidly managed.

The association of low serum salivary and pancreatic amylases with the increased use of lipids as an energy source in non-obese healthy women

OBJECTIVE

It is unknown whether low serum levels of salivary and pancreatic amylases are associated with the high combustion of carbohydrates or lipids for energy. Elevated blood ketones and a low respiratory quotient (RQ) can reflect the preferential combustion of lipids relative to carbohydrates. Therefore, using the data from our previous study, we investigated if low levels of serum amylases were associated with a high serum ketone level and low RQ in 60 healthy non-obese young women aged 20-39 years old.

RESULTS

Serum ketones [3-hydroxybutyric acid (3-HBA) and acetoacetic acid (AA)] were inversely correlated with RQs, but not body mass index (BMI) or glycated haemoglobin (HbA1c) levels. Logistic regression analysis showed that high levels of serum ketones (3-HBA ≥ 24 μmol/L and AA ≥ 17 μmol/L) and a low RQ (< 0.766) were significantly associated with low serum salivary (< 60 U/L) and pancreatic (< 29 U/L) amylase levels, respectively. These associations were not altered by further adjustments for age, BMI, HbA1c, and estimated glomerular filtration rate. These results confirm the high combustion of lipids for energy in individuals with low serum amylase levels, suggesting a close relationship between circulating amylases and internal energy production.

Capillary blood tests may overestimate ketosis: triangulation between three different measures of β-hydroxybutyrate

The ketone body β-hydroxybutyrate (BHB), assessed by a point-of-care meter in venous whole blood (BHBv), was used as the main outcome in a study on nutritional ketosis in healthy older adults. Two other BHB measures were also used in the study for validation and exploratory purposes, and here we report findings on correlation and agreement between those three methods. Ketosis in the range of 0-1.5 mmol/L was induced in 15 healthy volunteers by intake of medium-chain fatty acids after a 12-h fast. BHBv was assessed at 12 time points for 4 h. The same point-of-care meter was also used to test capillary blood (BHBc) at three time points, and a laboratory test determined total ketones (TK) in plasma (BHBp + acetoacetate) at four time points. A total of 180 cases included simultaneous data on BHBv, BHBc, BHBp, and TK. TK correlated with BHBp (Pearson's r = 0.99), BHBv (r = 0.91), and BHBc (r = 0.91), all P < 0.0001. BHBv and BHBp had good agreement in absolute values. However, the slope between BHBc and BHBv, measured with the same device, was in the range of 0.64-0.78 in different regression models, indicating substantially higher BHB concentrations in capillary versus venous blood. We conclude that all three methods are valid to detect relative changes in ketosis, but our results highlight the importance of method considerations and the possible need to adjust cutoffs, e.g., in the management of ketoacidosis and in the evaluation and comparison of dietary interventions.

Postoperative serum metabolites of patients on a low carbohydrate ketogenic diet after pancreatectomy for pancreatobiliary cancer: a nontargeted metabolomics pilot study

A ketogenic diet is a potential adjuvant cancer therapy that limits glucose availability to tumours while fuelling normal tissues with ketone bodies. We examined the effect of a low carbohydrate ketogenic diet (LCKD) (80% kcal from fat, ketogenic ratio 1.75:1, w/w) compared to a general hospital diet (GD) on serum metabolic profiles in patients (n = 18, ≥ 19 years old) who underwent pancreatectomy for pancreatobiliary cancer. Serum samples collected preoperatively (week 0) and after the dietary intervention (week 2) were analysed with a nontargeted metabolomics approach using liquid chromatography-tandem mass spectrometry. Serum β-hydroxybutyrate and total ketone levels significantly increased after 2 weeks of LCKD compared to GD (p < 0.05). Principal component analysis score plots and orthogonal partial least squares discriminant analysis also showed significant differences between groups at week 2, with strong validation. In all, 240 metabolites differed between LCKD and GD. Pathways including glycerophospholipid and sphingolipid metabolisms were significantly enriched in the LCKD samples. LCKD decreased C22:1-ceramide levels, which are reported to be high in pancreatic cancer, while increasing lysophosphatidylcholine (18:2), uric acid, citrulline, and inosine levels, which are generally low in pancreatic cancer. Postoperative LCKD might beneficially modulate pancreatic cancer-related metabolites in patients with pancreatobiliary cancer.

Ketogenic diet compromises vertebral microstructure and biomechanical characteristics in mice

Ketogenic diet (KD) compromised the microstructure of cancellous bone and the mechanical property in the appendicular bone of mice, while the effects of KD on the axial bone have not been reported. This study aimed to compare the changes in the microstructure and mechanical properties of the forth lumbar (L4) vertebra in KD and ovariectomized (OVX) mice. Forty eight-week-old female C57BL/6J mice were assigned into four groups: SD (standard diet) + Sham, SD + OVX, KD + Sham, and KD + OVX groups. L4 vertebra was scanned by micro-CT to examine the microstructure of cancellous bone, after which simulative compression tests were performed using finite element (FE) analysis. Vertebral compressive test and histological staining of the L4 and L5 vertebrae were performed to observe the biomechanical and histomorphologic changes. The KD + Sham and SD + OVX exhibited a remarkable declination in the parameters of cancellous bone compared with the SD + Sham group, while KD + OVX demonstrated the most serious bone loss in the four groups. The stiffness was significantly higher in the SD + Sham group than the other three groups, but no difference was found between the remaining groups. The trabecular parameters were significantly correlated with the stiffness. Meanwhile, the OVX + Sham and KD + OVX groups showed a significant decrease in the failure load of compressive test, while there was no difference between the KD + Sham and SD + Sham groups. These findings suggest that KD may compromise the vertebral microstructure and compressive stiffness to a similar level as OVX did, indicating adverse effects of KD on the axial bone of the mice.

The Clinical Case for the Integration of a Ketone Sensor as Part of a Closed Loop Insulin Pump System

Closed loop (CL) systems deliver insulin with a rapid onset and offset in action. Although favorable overall, the absence of a long-acting insulin increases the risk of diabetic ketoacidosis (DKA) which can occur with insulin delivery failure, acute illness, low carbohydrate diets, sodium glucose-linked transporter inhibitors, and high intensity exercise. A CL system relying entirely on interstitial glucose measurements may not provide an alert for DKA and many people with type 1 diabetes (T1D) do not carry a blood ketone meter and test-strips. Ketone sensing is theoretically feasible. A multianalyte platform incorporating a ketone sensor could provide an additional CL input without an increase in burden for the person with T1D, warning of impending DKA to allow remedial action to be taken. We outline the clinical case for inclusion of continuous ketone sensing as part of future CL systems.

Impact of angiotension I converting enzyme gene I/D polymorphism on running performance, lipid, and biochemical parameters in ultra-marathoners

The insertion (I) or deletion (D) polymorphism in the angiotension I converting enzyme gene, (ACE I/D, rs1799752) is associated with human exercise endurance and performance. However, most of the aforementioned studies focus on marathons, swimming, and triathlons, while the ACE polymorphism in ultra-marathoners has not yet been reported. We studied the impact of ACE I/D polymorphism in ultra-marathoners and investigated its relationship with lipid profiles, interleukin-6 (IL-6), and high-sensitivity C-reactive protein (hs-CRP) levels in runners before and after ultra-marathon racing.This observational study used data from a 100-km ultra-marathon in Taipei, Taiwan. Twenty-four male participants were analyzed for their ACE insertion/deletion polymorphism, lipid profiles, hs-CRP, IL-6 in serum immediately before and after ultra-marathon running.In our 24 subjects analyzed, 7, 14, and 3 subjects were of I/I, I/D, and D/D genotypes, respectively. Runners with the D polymorphism (I/D and D/D) showed a trend of better performance in the 100-km ultra-marathon (measured by completion time in minutes, P = .036). In this group, the previous best marathon performance was also significantly better than the I/I group (P = .047). After adjusting for body mass index (BMI), the difference in performance was not significant. Ketone levels, IL-6, and hs-CRP levels were highly increased at immediately and 24-hour post-race. No correlation was found between different ACE polymorphisms and common biochemical parameters examined.We report the first study in the impact of the ACE I/D (rs1799752) on ultra-marathoners. Presence of the D polymorphism in ACE gene is associated with better performance, although the BMI of the runners contribute as a major factor. There was no difference in the biochemical or lipid parameters measured among different ACE polymorphisms.

Spontaneous ketonuria and risk of incident diabetes: a 12 year prospective study

AIMS/HYPOTHESIS

Ketones may be regarded as a thrifty fuel for peripheral tissues, but their clinical prognostic significance remains unclear. We investigated the association between spontaneous fasting ketonuria and incident diabetes in conjunction with changes in metabolic variables in a large population-based observational study.

METHODS

We analysed 8703 individuals free of diabetes at baseline enrolled in the Korean Genome and Epidemiology Study, a community-based 12 year prospective study. Individuals with (n = 195) or without fasting ketonuria were matched 1:4 by propensity score. Incident diabetes was defined as fasting plasma glucose ≥7.0 mmol/l, post-load 2 h glucose ≥11.1 mmol/l on biennial OGTTs, or current use of glucose-lowering medication. Using Cox regression models, HRs for developing diabetes associated with the presence of ketonuria at baseline were analysed.

RESULTS

Over 12 years, of the 925 participants in the propensity score-matched cohort, 190 (20.5%) developed diabetes. The incidence rate of diabetes was significantly lower in participants with spontaneous ketonuria compared with those without ketonuria (HR 0.63; 95% CI 0.41, 0.97). Results were virtually identical when participants with fasting ketonuria were compared against all participants without ketonuria (after multivariate adjustment, HR 0.66; 95% CI 0.45, 0.96). During follow-up, participants with baseline ketonuria maintained lower post-load 1 h and 2 h glucose levels and a higher insulinogenic index despite comparable baseline values.

CONCLUSIONS/INTERPRETATION

The presence of spontaneous fasting ketonuria was significantly associated with a reduced risk of diabetes, independently of metabolic variables. Our findings suggest that spontaneous fasting ketonuria may have a potential preventive role in the development of diabetes.

The degree of postpartum metabolic challenge in dairy cows is associated with peripheral blood mononuclear cell transcriptome changes of the innate immune system

Dairy cows undergo a nutrient deficit immediately postpartum when lactational demands exceed nutrient intake. This occurs concurrently to an increased challenge due to bacterial and viral infections, yet ability for pathogen clearance is reduced despite a heightened and often host-damaging inflammatory response. We hypothesized that nutrient stress is associated with differences in the immune cell transcriptome. Our objective was therefore to investigate differentially expressed pathways (DEP) by RNA-seq in peripheral blood mononuclear cells harvested 3 weeks before and 1 week after calving from Holstein cows in low (L, n = 3) or high (H, n = 3) postpartum metabolic stress situations. Metabolic stress was defined by differences in circulating concentrations of glucose, fatty acids, and ketones postpartum. Cows in group H showed several upregulated DEP in relation to myeloid cell function and inflammatory response, as well as downregulation of the Th2 pathway. Principal components analysis showed that the transcriptome of group H postpartum samples was most different from all other samples. Differences in DE genes were noted even prepartum albeit fewer DE genes were identified and myeloid cell pathways in group H were generally downregulated at this time compared with group L. Samples within group L showed little difference between the two time points. We conclude that the metabolic phenotype of cows allowed us to identify differences in immune-regulatory pathways and that myeloid immune cells could play a dominant role in identifying these metabolically-associated differences that were demonstrated among a mixed mononuclear cell population.

Preserved glucose response to low-dose glucagon after exercise in insulin-pump-treated individuals with type 1 diabetes: a randomised crossover study

AIMS/HYPOTHESIS

This study aimed to compare the increase in plasma glucose after a subcutaneous injection of 200 μg glucagon given after 45 min of cycling with resting (study 1) and to investigate the effects of glucagon when injected before compared with after 45 min of cycling (study 2). We hypothesised that: (1) the glucose response to glucagon would be similar after cycling and resting; and (2) giving glucagon before the activity would prevent the exercise-induced fall in blood glucose during exercise and for 2 h afterwards.

METHODS

Fourteen insulin-pump-treated individuals with type 1 diabetes completed three visits in a randomised, placebo-controlled, participant-blinded crossover study. They were allocated by sealed envelopes. Baseline values were (mean and range): HbA_1c 54 mmol/mol (43-65 mmol/mol) or 7.1% (6.1-8.1%); age 45 years (23-66 years); BMI 26 kg/m² (21-30 kg/m²); and diabetes duration 26 years (8-51 years). At each visit, participants consumed a standardised breakfast 2 h prior to 45 min of cycling or resting. A subcutaneous injection of 200 μg glucagon was given before or after cycling or after resting. The glucose response to glucagon was compared after cycling vs resting (study 1) and before vs after cycling (study 2).

RESULTS

The glucose response to glucagon was higher after cycling compared with after resting (mean ± SD incremental peak: 2.6 ± 1.7 vs 1.8 ± 2.0 mmol/l, p = 0.02). As expected, plasma glucose decreased during cycling (-3.1 ± 2.8 mmol/l) but less so when glucagon was given before cycling (-0.9 ± 2.8 mmol/l, p = 0.002). The number of individuals reaching glucose values ≤3.9 mmol/l was the same on the 3 days.

CONCLUSIONS/INTERPRETATION

Moderate cycling for 45 min did not impair the glucose response to glucagon compared with the glucose response after resting. The glucose fall during cycling was diminished by a pre-exercise injection of 200 μg glucagon; however, no significant difference was seen in the number of events of hypoglycaemia.

TRIAL REGISTRATION

Clinicaltrials.gov NCT02882737 FUNDING: The study was funded by the Danish Diabetes Academy founded by Novo Nordisk foundation and by an unrestricted grant from Zealand Pharma.

Pioglitazone prevents the increase in plasma ketone concentration associated with dapagliflozin in insulin-treated T2DM patients: Results from the Qatar Study

Because of the unique mechanism of action of sodium-glucose co-transport inhibitors (SGLT2i), which is independent of insulin secretion and insulin action, members of this class of drugs effectively lower plasma glucose concentration when used in combination with all other antidiabetic agents, including insulin. Increased plasma ketone concentration has been reported in association with SGLT2i initiation, which, under certain clinical conditions, has developed into diabetic ketoacidosis. The daily insulin dose often is reduced at the time of initiating SGLT2i therapy in insulin-treated patients to avoid hypoglycaemia. However, reduction of insulin dose can increase the risk of ketoacidosis. In the present study, we examined the effect of the addition of dapagliflozin plus pioglitazone on plasma ketone concentration in insulin-treated T2DM patients and compared the results to the effect of dapagliflozin alone. A total of 18 poorly controlled, insulin-treated T2DM participants in the Qatar Study received dapagliflozin (10 mg) plus pioglitazone (30 mg), and 10 poorly controlled non-insulin-treated T2DM patients received dapagliflozin (10 mg) alone for 4 months. Dapagliflozin plus pioglitazone produced a robust decrease in HbA1c (-1.4%) and resulted in a 50% reduction in daily insulin dose, from 133 to 66 units, while dapagliflozin alone caused a 0.8% reduction in HbA1c. Dapagliflozin caused a four-fold increase in fasting plasma ketone concentration, while the combination of pioglitazone plus dapagliflozin was not associated with a significant increase (0.13 vs 0.15 mM) in plasma ketone concentration or in risk of hypoglycaemia. These results demonstrate that the addition of pioglitazone to dapagliflozin prevents the increase in plasma ketone concentration associated with SGLT2i therapy.

Pioglitazone improves hepatic mitochondrial function in a mouse model of nonalcoholic steatohepatitis

Pioglitazone is effective in improving insulin resistance and liver histology in patients with nonalcoholic steatohepatitis (NASH). Because dysfunctional mitochondrial metabolism is a central feature of NASH, we hypothesized that an important target of pioglitazone would be alleviating mitochondrial oxidative dysfunction. To this end, we studied hepatic mitochondrial metabolism in mice fed high-fructose high-transfat diet (TFD) supplemented with pioglitazone for 20 wk, using nuclear magnetic resonance-based ¹³C isotopomer analysis. Pioglitazone improved whole body and adipose insulin sensitivity in TFD-fed mice. Furthermore, pioglitazone reduced intrahepatic triglyceride content and fed plasma ketones and hepatic TCA cycle flux, anaplerosis, and pyruvate cycling in mice with NASH. This was associated with a marked reduction in most intrahepatic diacylglycerol classes and, to a lesser extent, some ceramide species (C22:1, C23:0). Considering the cross-talk between mitochondrial function and branched-chain amino acid (BCAA) metabolism, pioglitazone's impact on plasma BCAA profile was determined in a cohort of human subjects. Pioglitazone improved the plasma BCAA concentration profile in patients with NASH. This appeared to be related to an improvement in BCAA degradation in multiple tissues. These results provide evidence that pioglitazone-induced changes in NASH are related to improvements in hepatic mitochondrial oxidative dysfunction and changes in whole body BCAA metabolism.

Selected Physiological Effects of a Garcinia Gummi-Gutta Extract in Rats Fed with Different Hypercaloric Diets

Garcinia gummi-gutta (GGG) rind extract is effective for reducing appetite, body weight and adiposity of obese rodents fed high-fat (HF), high-sugar (HS) or high fat/sugar (HFS)-based diets, but these effects have not been simultaneously evaluated. Thirty obese (~425 g) male Wistar rats were fed for eleven weeks with six hypercaloric diets (4.1 kcal/g; five rats/diet) non-supplemented (HF, HS, HFS), or supplemented (HF+, HS+, HFS+) with GGG extract (5.9%), while rats from the control group (375 g) were fed a normocaloric diet (3.5 kcal/g). Body weight, dietary intake, body fat distribution, and histological and biochemical parameters were recorded. Compared to control rats, non-supplemented and supplemented groups consumed significantly less food (14.3% and 24.6% (−4.3 g/day), respectively) (p < 0.05). Weight loss was greater in the HF+ group (35⁻52 g), which consumed 1.9 times less food than the HS+ or HFS+ fed groups. The HF and HFS groups showed 40% less plasma triacylglycerides and lower glucose levels compared to the HF+. GGG-supplemented diets were associated with lower ketonuria. The HF+ diet was associated with the best anti-adiposity effect (as measured with the dual X-ray absorptiometry (DXA) and Soxhlet methods). The severity of hepatocyte lipidosis was HF > control > HF+, and no signs of toxicity in the testes were observed. The results indicate that GGG is more effective when co-administered with HF diets in obese rats.

Treatment with medium chain fatty acids milk of CD36-deficient preschool children

OBJECTIVE

CD36 deficiency is characterized by limited cellular long chain fatty acid uptake in the skeletal and cardiac muscles and often causes energy crisis in these muscles. However, suitable treatment for CD36 deficiency remains to be established. The aim of this study was to evaluate the clinical and metabolic effects of medium chain triacylglycerols (MCTs) in two CD36-deficient preschool children who often developed fasting hypoglycemia and exercise-induced myalgia.

METHODS

Fasting blood glucose, total ketone bodies, and free fatty acids were examined and compared for usual supper diets and for diets with replacement of one component with 2 g/kg of 9% MCT-containing milk (MCT milk). Changes in serum creatine kinase and alanine aminotransferase levels, resulting from replacement of glucose water intake with 1 g/kg of MCT milk and determined by using bicycle pedaling tasks, were examined and compared. Hypoglycemic and/or myalgia episodes in daily life were also investigated.

RESULTS

Biochemically, participants' blood glucose and total ketone bodies levels after overnight fasting substantially increased after dietary suppers containing MCT milk. Increases in serum creatine kinase and alanine aminotransferase levels resulting from the bicycle pedaling task were suppressed by MCT milk. Hypoglycemia leading to unconsciousness and tachycardia before breakfast decreased after introduction of dietary suppers containing MCT milk. Occurrence of myalgia in the lower limbs also decreased after intakes of MCT milk before long and/or strenuous exercising.

CONCLUSION

Our results suggest that MCTs can prevent fasting hypoglycemia and exercise-induced myalgia in CD36-deficient young children.

[Alcoholic ketoacidosis – a review]

Alcoholic ketoacidosis - a review A chronic alcoholic with severe metabolic acidosis presents a difficult diagnostic problem in the emergency room. Over and above methanol- and ethylene glycol intoxication, alcoholic ketoacidosis is a common but less recognized etiology. The disorder occurs in alcoholics who have had a recent binge drinking followed by the abrupt cessation of alcohol consumption because of abdominal pain and vomiting, with resulting dehydration, starvation, and then a β-hydroxybutyrate dominated ketoacidosis. Laboratory results may be misleading as the common urine-ketone tests may be negative or only weakly positive, since they only respond to acetoacetate. The short-term prognosis is good if treatment including replacement of fluid, electrolytes, glucose and thiamine is provided. However, recent studies have indicated that alcoholic ketoacidosis may be a significant cause of mortality in patients with alcohol dependence.

Regular and frequent feedback of specific clinical criteria delivers a sustained improvement in the management of diabetic ketoacidosis

Efficient management of diabetic ketoacidosis (DKA) improves outcomes and reduces length of stay. While clinical audit improves the management of DKA, significant and sustained improvement is often difficult to achieve. We aimed to improve the management of DKA in our trust through the implementation of quality improvement methodology. Five specific targets (primary drivers: fluid prescription, fixed rate intravenous insulin infusion, glucose measurement, ketone measurement and specialist referral) were selected following a baseline audit. Interventions (secondary drivers) were developed to improve these targets and included monthly feedback to departments of emergency medicine, acute medicine, and diabetes. Following our intervention, the mean average duration of DKA reduced from 22.0 hours to 10.2 hours. We demonstrate that regular audit cycles with interventions introduced through the plan-do-study-act model is an effective way to improve the management of DKA.

Determinants of the increase in ketone concentration during SGLT2 inhibition in NGT, IFG and T2DM patients

AIM

To examine metabolic factors that influence ketone production after sodium-glucose cotransport inhibitor (SGLT2) administration.

RESEARCH DESIGN AND METHODS

Fasting plasma glucose (FPG), insulin, glucagon, free fatty acid and ketone concentrations were measured in 15 type 2 diabetes mellitus (T2DM) and 16 non-diabetic subjects before and at day 1 and day 14 after treatment with empagliflozin.

RESULTS

Empagliflozin caused a 38 mg/dL reduction in FPG concentration in T2DM patients. However, it caused only a small but significant (7 mg/dL) reduction in the FPG concentration in impaired fasting glucose (IFG) subjects and did not affect FPG concentration in normal glucose tolerant (NGT) subjects. Empagliflozin caused a significant increase in mean plasma glucagon, free fatty acid (FFA) and ketone concentrations in T2DM subjects. However, empagliflozin did not cause a significant change in mean plasma insulin, glucagon or ketone concentrations in non-diabetic subjects. An index that integrates change in plasma glucose, insulin and FFA concentration at day 1 strongly correlates with plasma ketone concentration at day 1 (r = 0.85, P < .001) and day 14 (r = 0.63, r = 0.01) and predicts, with 86% sensitivity and 83% specificity, subjects at the top tertile for plasma ketone concentration after empagliflozin treatment.

CONCLUSION

Results of the present study demonstrate that SGLT2 inhibition exerts different metabolic effects in non-diabetic individuals as compared to diabetic patients.

Inhibitory Activities of Essential Oil Obtained from Turmeric and Its Constituents against β-Secretase

The need for a preventive agent against dementia led us to screen natural plant resources. Among the herbs and spices tested, turmeric, from rhizomes of Curcuma longa, showed high potency against β-secretase. The active principles were determined as α-turmerone, β-turmerone and ar-turmerone, with IC(50) values of 39, 62 and 92 μM respectively. In this study, the efficiency of collecting the essential oil using steam distillation of the volatile substance was disclosed The active principles were explored, and four sesquiterpenoids and five monoterpenoids were revealed as active principles against β-secretase; On the other hand, α-turmerone, β-turmerone and ar-turmerone were also investigated in a pharmacokinetic absorption experiment. After oral administration, these compounds were detected in an intact form in the brain and serum. These results suggest that consumption of-turieric constituents may prevent dementia.

Prevention of Insulin-Induced Hypoglycemia in Type 1 Diabetes with Predictive Low Glucose Management System

BACKGROUND

Sensor-augmented pump therapy (SAPT) with algorithms to predict impending low blood glucose and suspend insulin delivery has the potential to reduce hypoglycemia exposure. The aim of this study was to determine whether predictive low glucose management (PLGM) system is effective in preventing insulin-induced hypoglycemia in controlled experiments.

METHODS

Two protocols were used to induce hypoglycemia in an in-clinic environment. (A) Insulin bolus: Insulin was administered as a manual bolus through the pump. (B) Increased basal insulin: Hypoglycemia was induced by increasing basal rates overnight to 180%. For both protocols, participants were randomized and studied on 2 separate days; a control day with SAPT alone and an intervention day with SAPT and PLGM activated. The predictive algorithm was programmed to suspend basal insulin infusion when sensor glucose was predicted to be <80 mg/dL in 30 min. The primary outcome was the requirement for hypoglycemia treatment (symptomatic hypoglycemia or plasma glucose <50 mg/dL) and was compared in both control and intervention arms.

RESULTS

With insulin bolus, 24/28 participants required hypoglycemia treatment with SAPT alone compared to 5/28 participants when PLGM was activated (P ≤ 0.001). With increased basal rates, all the eight SAPT-alone participants required treatment for hypoglycemia compared to only one with SAPT and PLGM. There was no post pump-suspend hyperglycemia with insulin bolus (P = 0.4) or increased basal rates (P = 0.69) in participants with 2-h pump suspension on intervention days.

CONCLUSIONS

SAPT with PLGM reduced the requirement for hypoglycemia treatment following insulin-induced hypoglycemia in an in-clinic setting.

Pharmacokinetics of Paradol Analogues Orally Administered to Rats

The kinetics parameters of paradols with different acyl chain lengths have been evaluated to determine their antiobesity site of action. Rats were orally administered olive oil containing 0-, 6-, 8-, or 12-paradol, and blood samples were collected at different time points. The concentrations of the paradols in the plasma were analyzed both with and without β-glucuronidase treatment. The area under the plasma concentration-time curve from 0 to 24 h (AUC(0-24h)) of the parent compounds decreased with increasing acyl chain length. Whereas 12-paradol showed the largest AUC(0-24h) with the longest time to reach its maximum plasma concentration of all of the compounds tested, the AUC(0-24h) values of the metabolites decreased with increasing acyl chain length. These results indicate that increasing acyl chain length leads to a decrease in the absorption of paradols via the intestinal tract, the wall of which was estimated to be their antiobesity site of action.

Effects of a ketogenic diet on auditory gating in DBA/2 mice: A proof-of-concept study

Although the ketogenic diet has shown promise in a pilot study and case report in schizophrenia, its effects in animal models of hypothesized disease mechanisms are unknown. This study examined effects of treatment with the ketogenic diet on hippocampal P20/N40 gating in DBA/2 mice, a translational endophenotype that mirrors inhibitory deficits in P50 sensory gating in schizophrenia patients. As expected, the diet increased blood ketone levels. Animals with the highest ketone levels showed the lowest P20/N40 gating ratios. These preliminary results suggest that the ketogenic diet may effectively target sensory gating deficits and is a promising area for additional research in schizophrenia.

Role of Hyperketonemia in Inducing Oxidative Stress and Cellular Damage in Cultured Hepatocytes and Type 1 Diabetic Rat Liver

BACKGROUND/AIMS

Type 1 diabetic (T1D) patients have a higher incidence of liver disease. T1D patients frequently experience elevated plasma ketone levels along with hyperglycemia. However, no study has examined whether hyperketonemia per se has any role in excess liver damage in T1D. This study investigates the hypothesis that hyperketonemia can induce oxidative stress and cellular dysfunction.

METHODS

STZ treated diabetic rats, FL83B hepatocytes, and GCLC knocked down (GSH deficient) hepatocytes were used.

RESULTS

The blood levels of ALT and AST, biomarkers of liver damage, and ketones were elevated in T1D rats. An increase in NOX4 and ROS along with a reduction in GSH and GCLC levels was observed in T1D rat livers in comparison to those seen in non-diabetic control or type 2 diabetic rats. MCP-1 and ICAM-1 were also elevated in T1D rat livers and ketone treated hepatocytes. Macrophage markers CCR2 and CD11A that interact with MCP-1, and ICAM-1 respectively, were also elevated in the T1D liver, indicating macrophage infiltration. Additionally, activated macrophages increased hepatocyte damage with ketone treatment, which was similar to that seen in GCLC knockdown hepatocytes without ketones.

CONCLUSION

Hyperketonemia per se can induce macrophage mediated damage to hepatocytes and the liver, caused by GSH depletion and oxidative stress up regulation in T1D.

Use of a Combined Blood-Glucose- and ß-Ketone-Measuring Device Improves Glycemic Control in Insulin-Treated Patients With Diabetes: The Gold Plus Study

BACKGROUND

Using self-measurements of blood glucose (SMBG) is daily routine for patients with insulin-treated diabetes, however measuring ß-ketones in blood is not widespread. How the use of a combined device, which can measure both, is accepted in daily routine by patients and will lead to better glycemic control is not well studied.

METHODS

This multicenter, prospective, noninterventional study assessed the impact of routine use of the GlucoMen® LX Plus on patient acceptance, usage and glycemic control among insulin-treated patients with diabetes mellitus type 1 and type 2. A1c and self-reported frequency of SMBG were evaluated at baseline and also postprandial SMBG, ß-ketone measurements, and use of reminders after 3 and 6 months of use. A total of 631 patients, 254 type 1/350 type 2 (27 no type specified), with mean (SD) baseline A1c 8.5% (1.5), age 54.6 (15.6) years, and 47.3% female were studied.

RESULTS

Frequent use of SMBG at baseline led to a higher decrease in A1c at 6 month (V3): -0.3% if SMBG measured up to 1/day versus -0.9% in 4-6/day. Increase of SMBG frequency during the study showed also a negative correlation to A1c, 9.2% at V1 versus 7.6% at V3. Postprandial SMBG was done by 77.7% and ß-ketone measurements by 45.5% of all patients; the reminders were used by 33.4% and led to an increased frequency of SMBG at 6 months.

CONCLUSIONS

A combined device for SMBG and ß-ketone measurements is well accepted by patients with insulin-treated diabetes and can lead through the avoidance or detection of ketoacidosis/increased frequency of SMBG and increased awareness of the patients to an improved glycemic outcome.

Comparative performance assessment of point-of-care testing devices for measuring glucose and ketones at the patient bedside

Point-of-care (POC) testing devices for monitoring glucose and ketones can play a key role in the management of dysglycemia in hospitalized diabetes patients. The accuracy of glucose devices can be influenced by biochemical changes that commonly occur in critically ill hospital patients and by the medication prescribed. Little is known about the influence of these factors on ketone POC measurements. The aim of this study was to assess the analytical performance of POC hospital whole-blood glucose and ketone meters and the extent of glucose interference factors on the design and accuracy of ketone results. StatStrip glucose/ketone, Optium FreeStyle glucose/ketone, and Accu-Chek Performa glucose were also assessed and results compared to a central laboratory reference method. The analytical evaluation was performed according to Clinical and Laboratory Standards Institute (CLSI) protocols for precision, linearity, method comparison, and interference. The interferences assessed included acetoacetate, acetaminophen, ascorbic acid, galactose, maltose, uric acid, and sodium. The accuracies of both Optium ketone and glucose measurements were significantly influenced by varying levels of hematocrit and ascorbic acid. StatStrip ketone and glucose measurements were unaffected by the interferences tested with exception of ascorbic acid, which reduced the higher level ketone value. The accuracy of Accu-Chek glucose measurements was affected by hematocrit, by ascorbic acid, and significantly by galactose. The method correlation assessment indicated differences between the meters in compliance to ISO 15197 and CLSI 12-A3 performance criteria. Combined POC glucose/ketone methods are now available. The use of these devices in a hospital setting requires careful consideration with regard to the selection of instruments not sensitive to hematocrit variation and presence of interfering substances.

Utility of ketone measurement in the prevention, diagnosis and management of diabetic ketoacidosis

Ketone measurement is advocated for the diagnosis of diabetic ketoacidosis and assessment of its severity. Assessing the evidence base for ketone measurement in clinical practice is challenging because multiple methods are available but there is a lack of consensus about which is preferable. Evaluating the utility of ketone measurement is additionally problematic because of variability in the biochemical definition of ketoacidosis internationally and in the proposed thresholds for ketone measures. This has led to conflicting guidance from expert bodies on how ketone measurement should be used in the management of ketoacidosis. The development of point-of-care devices that can reliably measure the capillary blood ketone β-hydroxybutyrate (BOHB) has widened the spectrum of applications of ketone measurement, but whether the evidence base supporting these applications is robust enough to warrant their incorporation into routine clinical practice remains unclear. The imprecision of capillary blood ketone measures at higher values, the lack of availability of routine laboratory-based assays for BOHB and the continued cost-effectiveness of urine ketone assessment prompt further discussion on the role of capillary blood ketone assessment in ketoacidosis. In the present article, we review the various existing methods of ketone measurement, the precision of capillary blood ketone as compared with other measures, its diagnostic accuracy in predicting ketoacidosis and other clinical applications including prevention, assessment of severity and resolution of ketoacidosis.

Efficacy of quantitative capillary beta-hydroxybutyrate measurement in the diagnosis of diabetic ketoacidosis: a comparison to quantitative serum ketone measurement by nitroprusside reaction

OBJECTIVE

To examine the efficacy of using capillary beta-hydroxy butyrate (beta-OHB) levels in comparison with serum ketone levels in distinguishing diabetic ketoacidosis (DKA) from non-DKA states in patients who had severe hyperglycemia and to determine a cut-off level of capillary beta-OHB that is best for the diagnosis of DKA.

MATERIAL AND METHOD

Diabetic patients who presented with capillary blood glucose of > or = 400 mg/dL were studied. Capillary beta-OHB levels were measured by using a ketometer (OptiumXceed) at the same time as blood sample collection for biochemical tests and serum ketone measurement using nitroprusside reaction. The American Diabetes Association (ADA) criteria 2012 were used as the gold standard in the diagnosed of DKA.

RESULTS

There were 13 cases (34.2%) with DKA (DKA group) and 25 cases (65.8%) without DKA (non-DKA group). There was no difference in plasma glucose levels between both groups. (DKA group = 714.2 +/- 367.6 mg/dl vs. non-DKA group = 589.4 +/- 220.2 mg/dl). The DKA group had significantly higher serum ketone (7.2 +/- 3.6 vs. 0.28 +/- 0.05 mmol/L, p < 0.001) and capillary beta-OHB levels (4.3 +/- 0.7 vs. 1.0 +/- 1.1 mmol/L, p < 0.001) than did the non-DKA group. Capillary beta-OHB levels significantly correlated to serum anion gap values (r = 0.828, p < 0.001), serum bicarbonate (r = 0.715, p < 0.001), and ketone (r = 0.72, p < 0.001) levels. ROC analyses showed that a capillary beta-OHB level of > 3.1 mmol/L was the best cut-off level for the diagnosis of DKA, and yielded a sensitivity of 100% (95% CI = 75.1-100) with a specificity of 96% (95% CI = 79.6-99.3).

CONCLUSION

Using a cut-off capillary beta-OHB level of > 3.1 mmol/L is highly effective in the diagnosis of DKA in patients who presented with hyperglycemia. Quantitative measurement of capillary beta-OHB levels using a ketometer offers an immediate result that is useful for a reliable triage of screening for DKA in patients presented with severe hyperglycemia.

Targeting metabolism with a ketogenic diet during the treatment of glioblastoma multiforme

Retrospective data suggests that low serum glucose levels during the treatment of glioblastoma multiforme (GBM) may improve clinical outcomes. As such, many patients are implementing a ketogenic diet (KD) in order to decrease serum glucose flux while simultaneously elevating circulating ketones during radiation therapy and chemotherapy for the treatment of GBM. With IRB approval, a retrospective review of patients with high-grade glioma treated with concurrent chemoradiotherapy and adjuvant chemotherapy was carried out from August 2010 to April 2013. Serum glucose and ketone levels, dexamethasone dose, and toxicity of patients undergoing a KD during treatment were also assessed. Blood glucose levels were compared between patients on an unspecified/standard diet and a KD. Toxicity was assessed by Common Terminology Criteria for Adverse Events version 4. In total, 53 patients were analyzed. Six underwent a KD during treatment. The diet was well tolerated with no grade III toxicity and one episode of grade II fatigue. No episodes of symptomatic hypoglycemia were experienced. Four patients are alive at a median follow-up of 14 months. The mean blood glucose of patients on a standard diet was 122 versus 84 mg/dl for those on a KD. Based on this retrospective study, a KD appears safe and well tolerated during the standard treatment of GBM. Dietary restriction of carbohydrates through a KD reduces serum glucose levels significantly, even in conjunction with high dose steroids, which may affect the response to standard treatment and prognosis. Larger prospective trials to confirm this relationship are warranted.

Septic ketoacidosis

Various unmeasured anions other than lactate appear in the blood of septic patients, including ketones. However, the occurrence of sepsis-induced ketoacidosis without diabetes mellitus has not been reported to date. We herein describe severe ketoacidosis in a patient with septic shock despite the absence of diabetes, alcohol and starvation. A 76-year-old woman presented with septic shock due to acute obstructive cholangitis. She exhibited ketoacidosis and a remarkably strong ion gap, except for ketones. Sepsis alone may lead to ketoacidosis in patients without diabetes under specific conditions. The accumulation of ketones and other strong anions can occur in cases involving a decreased metabolic function. There may be a pathological condition called septic ketoacidosis.

A gestational ketogenic diet alters maternal metabolic status as well as offspring physiological growth and brain structure in the neonatal mouse

BACKGROUND

The use of the ketogenic diet (KD) among women of child-bearing age has been increasing, leading to increased interest in identifying the diet's suitability during gestation. To date, no studies have thoroughly investigated the effect of a gestational KD on offspring growth. Since ketones have been reported to play a role in cerebral lipid and myelin synthesis, it is particularly important to investigate the diet's impact on brain anatomy of the offspring.

METHODS

To fill this knowledge gap we imaged CD-1 mouse neonates whose mothers were fed either a standard diet (SD) or a KD prior to and during gestation. Images were collected at postnatal (P) 11.5 and 21.5 using Magnetic Resonance Imaging (MRI). Maternal metabolic status was also tracked during lactation, by following their body weight, blood glucose, ketone, cholesterol, and triglyceride concentrations.

RESULTS

The KD dams exhibit a significant reduction in maternal fertility and litter size, as well as a high risk of developing fatal ketoacidosis by mid-lactation. To increase survival of the KD dams and offspring, fostering of P2.5 pups (from both KD and SD litters) by SD-foster dams was carried out. This resulted in stabilization of blood ketones of the KD dams, and aversion of the fatal ketoacidosis. We also note a slower and smaller weight loss for the KD compared with the SD dams. The average fostered KD pup exhibits retarded growth by P21.5 compared with the average fostered SD pup. An anatomical comparison of their brains further revealed significant structural differences at P11.5, and particularly at P21.5. The KD brain shows a relative bilateral decrease in the cortex, fimbria, hippocampus, corpus callosum and lateral ventricle, but a relative volumetric enlargement of the hypothalamus and medulla.

CONCLUSION

A gestational ketogenic diet deleteriously affects maternal fertility and increases susceptibility to fatal ketoacidosis during lactation. Prenatal and early postnatal exposure to a ketogenic diet also results in significant alterations to neonatal brain structure, and results in retarded physiological growth. These alterations could be accompanied by functional and behavioural changes in later postnatal life.

The effect of experimentally induced chronic hyperglycaemia on serum and pancreatic insulin, pancreatic islet IGF-I and plasma and urinary ketones in the domestic cat (Felis felis)

Like in humans, diabetes mellitus is on the rise in cats. Feline diabetes is a suitable model for human type-2 diabetes. We investigated magnitude and timing of insulin suppression with induced hyperglycaemia and its relationship to plasma and urinary ketones and to pancreatic islet insulin. IGF-I is under discussion as a protective mechanism but little is known about its role in diabetes in general and its distinct localisation in feline pancreatic islets in particular. Thirteen healthy, adult cats were allocated to 2 groups and infused with glucose to maintain their blood glucose at a high or moderate concentration for 42 days resulting in insulin secretion suppression. After initial increase, insulin levels declined to baseline but were still detectable in the blood at a very low level after 6 weeks of glucose infusion and then increased after a 3 week recovery period. While IGF-I in healthy cats was primarily located in glucagon cells, in hyperglycaemia-challenge IGF-I was pronounced in the β-cells 3 weeks after ceasation of infusion. Six/8 cats developing glucose toxicity became ketonuric after 3-4 weeks. Gross lipaemia occurred approx 1 week prior to ketonuria. Ketonuric cats required 1-2 weeks of insulin therapy after-infusion until β-cell recovery. In conclusion, ketosis and hyperlipidaemia are likely to occur in diabetic cats with glucose at 30 mmol/L, especially after ≥2 weeks. Three weeks after ceasation of infusions, clinical and morphological recovery occurred. We propose a local protective effect of IGF-I to support survival and insulin production in the hyperglycaemic state and recovery period.

Parental mastery of continuous subcutaneous insulin infusion skills and glycemic control in youth with type 1 diabetes

OBJECTIVE

The purpose of this study is to determine whether parental knowledge of the continuous subcutaneous insulin infusion (CSII) device affects glycemic control as measured by hemoglobin A1c (A1C) level.

SUBJECTS AND METHODS

Parents of children with type 1 diabetes mellitus (T1DM) using CSII completed a 14-item questionnaire. Questions 1-10 were knowledge-based questions that required the parent to extract specific information from their child's CSII device. Questions 11-14 asked parents to provide a self-assessment of their CSII knowledge.

RESULTS

Twenty-two parents of youth with T1DM participated in the study. Ten of the youth were in the Low-A1C group (A1C<8%), and the other 12 were in the High-A1C group (A1C≥8%). Parents of youth in the Low-A1C group scored statistically better on the 10-item performance survey than parents of youth in the High-A1C group. Most of the parents of children in the Low-A1C group responded that they knew their child's insulin pump "very well" and that their pump knowledge had "increased" since their child started on the insulin pump.

CONCLUSIONS

Our findings reveal that youth with T1DM whose parents are more knowledgeable about pump functions have optimal glycemic control as evidenced by A1C. These findings underscore the importance of ongoing pump training for both pediatric patients and their parents.

Ketosis-resistant diabetes: a rare case in unlikely territory

BACKGROUND

Ketosis-resistant diabetes is a syndrome that has undergone numerous classification schemes in the past. In 1979, the National Diabetes Data Group (NDDG) introduced an association of malnutrition and diabetes. In 1985, the World Health Organization (WHO) created a new diabetes category called malnutrition-related diabetes mellitus (MRDM). MRDM consisted of two subclasses: fibrocalculous pancreatic diabetes (FCPD) and protein-deficient pancreatic diabetes (PDPD). Ketosis-resistant diabetes of the young (KRDY) was included in the subclass of PDPD. We report a rare case of a 37-year-old Sudanese immigrant with ketosis-resistant diabetes.

CASE

A previously healthy 37-year-old male presented with increased lethargy, polydipsia, polyuria and weight loss for the last seven to eight months. The patient had immigrated to the U.S. from his native country of Sudan about seven years earlier. He was hemodynamically stable. Physical exam was unremarkable with no evidence of retinopathy or neuropathy. Initial laboratory findings revealed a random blood sugar of 1,409 mg/dl and hemoglobin A1C of 17.8 percent. Urinalysis showed negative proteinuria, positive glycosuria, but only trace ketones were detected. Interestingly, the patient's serum ketones were negative. Arterial blood gas revealed PH 7.37, PCO2 47, P02 108 and HCO3 27. Further diagnostic workup revealed C-peptide 0.36, insulin antibodies less than 2, glutamic acid decarboxylase (GAD) antibodies less than 0.5, ICA 512 antibodies 2.9 and negative anti-islet cell antibodies. An abdominal ultrasound did not show any evidence of pancreatic calcifications or any pathology. Aggressive fluid resuscitation and intravenous insulin was initiated. The patient's hospital course was uncomplicated. He responded well to intravenous insulin drip and hydration. He was eventually transitioned to subcutaneous insulin. He was discharged three days later on a home regimen that included Lantus 28 units SQ at night, Novolog 8 units SQ with meals and a sliding scale with Novolog as needed. The patient's recent follow-up appointment revealed adequate glycemic control with HbA1C level of 7 percent.

CONCLUSION

Our patient did not meet criteria for either type 1 or type 2 diabetes mellitus. After a literature review of atypical etiologies of diabetes and comparing them to our patient, we concluded that the most likely diagnosis was KRDY. In light of a high influx of refugees and immigrants to the U.S., we should entertain. KRDY and other rare causes of diabetes mellitus in patients not satisfying criteria of either type 1 or type 2 diabetes.

Characterization of the pharmacokinetics of a liposomal formulation of eribulin mesylate (E7389) in mice

Eribulin mesylate (E7389), a tubulin and microtubule inhibitor, has been approved to treat metastatic breast cancer in certain patient populations. A liposomal formulation of E7389, E7389-LF, aims to increase the therapeutic profile of E7389. As determining the free drug concentration is crucial for the assessment of efficacy and toxicity of liposomal drug, in this study, an ultracentrifugation method coupled with LC-MS/MS was developed to separate the free E7389 from liposomal and protein bound E7389. The pharmacokinetics of the free E7389 after dosing either E7389 or E7389-LF was characterized. The concentration ratio of E7389 in ultracentrifuged mice plasma (UCM) vs E7389 in plasma after a 2mg/kg i.v. of E7389 ranged from 54.19% to 65.41%, which was similar to the free fraction in the mouse plasma. The respective concentration ratio of E7389 in UCM vs E7389 in plasma after a 2mg/kg i.v. of E7389-LF ranged from 0.07% to 0.59%, and the exposure, expressed as AUC, of UCM/plasma ratio was determined to be 0.2%. Pharmacokinetic modeling was performed to estimate the release kinetics of E7389 from E7389-LF, and the release was best described by a first order rate constant k(rel) 0.078 h(-1). Sensitivity analysis demonstrated that further decrease the release rate constant by adjusting liposome formulation would lead to decreased C(max) and much longer half-life of UCM E7389, which might result in better efficacy and lower toxicity.