Plasma Acetone Research Articles

Metabolomics and a Breath Sensor Identify Acetone as a Biomarker for Heart Failure

Multi-omics delivers more biological insight than targeted investigations. We applied multi-omics to patients with heart failure with reduced ejection fraction (HFrEF). 46 patients with HFrEF and 20 controls underwent metabolomic profiling, including liquid/gas chromatography mass spectrometry (LC-MS/GC-MS) and solid-phase microextraction (SPME) volatilomics in plasma and urine. HFrEF was defined using left ventricular global longitudinal strain, ejection fraction and NTproBNP. A consumer breath acetone (BrACE) sensor validated results in n = 73. 28 metabolites were identified by GCMS, 35 by LCMS and 4 volatiles by SPME in plasma and urine. Alanine, aspartate and glutamate, citric acid cycle, arginine biosynthesis, glyoxylate and dicarboxylate metabolism were altered in HFrEF. Plasma acetone correlated with NT-proBNP (r = 0.59, 95% CI 0.4 to 0.7), 2-oxovaleric and cis-aconitic acid, involved with ketone metabolism and mitochondrial energetics. BrACE > 1.5 ppm discriminated HF from other cardiac pathology (AUC 0.8, 95% CI 0.61 to 0.92, p < 0.0001). Breath acetone discriminated HFrEF from other cardiac pathology using a consumer sensor, but was not cardiac specific.

The Diurnal Blood Metabolome and Effects of Vitamin D Supplementation: A Randomised Crossover Trial in Postmenopausal Women.

A way to maintain an adequate vitamin D status is through supplementation. Demonstration of blood-metabolome rhythmicity of vitamin D3 post-dosing effects is lacking in the pharmaco-metabonomics area. Thus, the overall aim of this study was to investigate the diurnal changes in the blood metabolome and how these are affected by vitamin D3 supplementation. The study was conducted as a crossover study, and the treatment included 200 µg (8000 IU) of vitamin D3 as compared with placebo with a washout period of at least 10 days. The participants were postmenopausal women aged 60–80 years (N = 29) with vitamin D insufficiency (serum 25-hydroxyvitamin D < 50 nmol/L) but otherwise healthy. During the intervention day, blood samples were taken at 0 h, 2 h, 4 h, 6 h, 8 h, 10 h, 12 h, and 24 h, and plasma was analysed by proton nuclear magnetic resonance (NMR) spectroscopy as a metabolomics approach. In general, diurnal effects were identified for the majority of the 20 quantified metabolites, and hierarchical cluster analysis revealed a change in the overall plasma metabolome around 12 AM (6 h after intervention), suggesting that the diurnal rhythm is reflected in two diurnal plasma metabolomes; a morning metabolome (8–12 AM) and an afternoon/evening metabolome (2–8 PM). Overall, the effect of vitamin D supplementation on the blood metabolome was minor, with no effect on the diurnal rhythm. However, a significant effect of the vitamin D supplementation on plasma acetone levels was identified. Collectively, our findings reveal an influence of diurnal rhythm on the plasma metabolome, while vitamin D supplementation appears to have minor influence on fluctuations in the plasma metabolome.

Metabolomics and a breath sensor identify acetone as a biomarker for heart failure

Abstract Introduction Metabolomics delivers more biological and clinical insight than targeted investigations. We applied metabolomics to patients with heart failure (HF) with reduced ejection fraction (HFrEF). Methods 46 patients with HFrEF and 20 controls underwent metabolomic profiling, including liquid/gas chromatography mass spectrometry (LC-MS/GC-MS), nuclear magnetic resonance (NMR) metabolomics and solid-phase microextraction (SPME) volatilomics in plasma and urine. HFrEF was defined using left ventricular global longitudal strain (GLS) &amp;lt;18%, ejection fraction &amp;lt;50% and NTproBNP ≥35 pmol/L. A low cost consumer breath acetone (BrACE) sensor validated SPME results in 69 patients. Results 34 metabolites were identified by GCMS, 33 by LCMS and 2 volatiles by SPME (acetone, 2-pentanone in plasma and urine). Alanine, aspartate and glutamate, citric acid cycle, arginine biosynthesis, glyoxylate and dicarboxylate metabolism were altered in HFrEF. Plasma acetone correlated with NT-proBNP (r=0.59, 95% CI 0.4 to 0.7), triacylglycerol (55:9), 2-oxovaleric and cis-aconitic acid, involved with ketone metabolism and mitochondrial energetics. BrACE &amp;gt;1.5 ppm discriminated HF from other cardiac pathology (AUC 0.88, 95% CI 0.77 to 0.99, P&amp;lt;0.0001). Conclusion Breath acetone was detectable in HFrEF patients using a consumer sensor ($1/test) and although not cardiac specific, discriminated HF from other cardiac pathology. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Health Research Council of New Zealand

A059 Metabolomics and a Breath Sensor Identify Acetone as a Biomarker for Heart Failure

Metabolomics delivers more biological and clinical insight than targeted investigations. We applied metabolomics to patients with heart failure (HF) with reduced ejection fraction (HFrEF). 46 patients with HFrEF and 20 controls underwent metabolomic profiling, including liquid/gas chromatography mass spectrometry (LC-MS/GC-MS), nuclear magnetic resonance (NMR) metabolomics and solid-phase microextraction (SPME) volatilomics in plasma and urine. HFrEF was defined using left ventricular global longitudal strain (GLS) < 18%, ejection fraction < 50% and NTproBNP ≥ 35 pmol/L. A low cost consumer breath acetone (BrACE) sensor validated SPME results in 69 patients. 34 metabolites were identified by GCMS, 33 by LCMS and 2 volatiles by SPME (acetone, 2-pentanone in plasma and urine). Alanine, aspartate and glutamate, citric acid cycle, arginine biosynthesis, glyoxylate and dicarboxylate metabolism were altered in HFrEF. Plasma acetone correlated with NT-proBNP (r = 0.59, 95% CI 0.4 to 0.7), triacylglycerol (55:9), 2-oxovaleric and cis-aconitic acid, involved with ketone metabolism and mitochondrial energetics. BrACE > 1.5 ppm discriminated HF from other cardiac pathology (AUC 0.88, 95% CI 0.77 to 0.99, P < 0.0001). Breath acetone was detectable in HFrEF patients using a consumer sensor ($1/test) and although not cardiac specific, discriminated HF from other cardiac pathology.

P183 An off-line end-tidal breath sampling method in anaesthetised patients with analysis by selected ion flow tube mass spectrometry

IntroductionMonitoring of breath volatiles could provide non-invasive rapid assessment of metabolic stress, inflammation and intravenous anaesthetic drug concentrations in anaesthetised patients. This study was designed to validate an off-line single...

Chronic Acetonemia Alters Liver Oxidative Balance and Lipid Content in Rats. A Model of Nash?

Acetone is considered to be a substance that can disturb cellular oxidative status, being also associated with the production of glucose during its metabolization. The objective of the present study was to determine the effects of chronic treatment with acetone in oxidative stress and metabolic parameters in rats. Twenty male Wistar rats were divided into two groups: control (CG) and chronic acetone group (CAG). After 28 days of acetone ingestion in a 5% aqueous solution (CAG) or water (CG) the animals were euthanized and urine, plasma and liver were collected for the determination of acetone, glucose, lipemia, hepatic fat, malondialdehyde (MDA), reduced glutathione (GSH), and vitamin E. As expected, urinary and plasma acetone levels were higher in CAG. There was no difference in hepatic MDA values between groups, whereas hepatic GSH was lower in CAG than in CG and hepatic vitamin E was higher in CAG than in CG. There was also an increase in glycemia, cholesterolemia and hepatic fat in CAG compared to CG. Chronic treatment with a 5% acetone solution produced an increase in acetonemia that was able to promote changes in hepatic oxidative metabolism and in lipid content in rats similar to those observed in nonalcoholic steatohepatitis.

Direct Solid-Support Sample Loading for Fast Cataluminescence Determination of Acetone in Human Plasma

In the current manuscript we describe the development of a novel cataluminescence (CTL) sensor coupled with ionic liquids (ILs)-based headspace solid-phase microextraction (HS-SPME) technologies for the quantification of human plasma acetone levels associated with diabetic disease ex vivo. The unique properties of ILs, such as their nonvolatile and nonflammable nature, coupled with their high thermal stability allow ILs to be conveniently adopted as pseudosolid carriers for direct loading of acetone into a CTL sensor without matrix interference. Acetone from diabetic patient plasma and plasma samples spiked with acetone along with methanol, ethanol, and formaldehyde was conveniently and rapidly extracted and enriched in 3 microL of IL and then rapidly quantified by our CTL sensor. The presence of plasma alone or spiked plasma containing methanol, ethanol, or formaldehyde did not interfere with acetone measurements. HS-SPME-CTL provides higher enrichment efficiency than headspace single-drop microextraction-based CTL (HS-SDME-CTL) methods, possibly due to that the thin film formed in HS-SPME instead of the single IL drop in HS-SDME increases the exchange area for extracted acetone. The enrichment efficiency by HS-SPME-CTL was almost 80-fold higher than that with direct injection using the same volume of aqueous samples and more than 6-fold higher than that using HS-SDME-CTL. Considering that ILs can be easily prepared from inexpensive materials and tuned by the combination of different anions and cations for the extraction of specific analytes from various solvent media, this proposed technology raises an exciting possibility by employing HS-SPME-CTL for the fast determination of specific targets in many fields.

Breath acetone predicts plasma ketone bodies in children with epilepsy on a ketogenic diet

Objective The high-fat ketogenic diet has long been used to treat refractory childhood seizures, but whether there is a relation between the degree of ketosis and effectiveness of seizure control remains unclear. Frequent measurements of plasma ketones are difficult in children so the goal was to determine the utility of breath acetone as a marker of systemic ketosis and seizure control in children given the ketogenic diet because of seizures refractory to medication. Methods In experiment I, breath acetone and plasma ketones were assessed every 2 h during an 8-h test day in seven children. In experiment II, a preliminary assessment of the possible relation between breath acetone and seizure frequency was made over 14 d in five children and one adolescent on the ketogenic diet. Results Breath acetone was positively and curvilinearly related to plasma acetone ( r 2 = 0.99, P < 0.0001), plasma acetoacetate ( r 2 = 0.89, P < 0.0001), and plasma β-hydroxybutyrate ( r 2 = 0.94, P < 0.0001). No significant relation was found between breath acetone and seizure frequency or change in seizure frequency. Conclusions Breath acetone is indicative of systemic ketosis while on the ketogenic diet. However, owing to the wide range of seizure types and plasma acetone, more subjects will be needed to determine whether there is a clear link between breath acetone and seizure frequency or decreased seizure frequency while on the high-fat ketogenic diet.

Acetone metabolism in humans during diabetic ketoacidosis.

Plasma acetone turnover rates were measured with the primed continuous infusion of 2-[14C]acetone in patients with moderate to severe diabetic ketoacidosis. Plasma acetone turnover rates ranged from 1.52 to 15.9 mumol X kg-1 X min-1 (108-1038 mumol X 1.73 m-2 X min-1) and were directly related to the plasma acetone concentrations that ranged from 0.47 to 7.61 mM. The average acetone turnover rate was 6.45 mumol X kg-1 X min-1 (533 mumol X 1.73 m-2 X min-1), a value twice that obtained in a similar group of diabetic ketoacidotic patients via the single-injection technique of 2-[14C]acetone administration. Degradation of urine glucose revealed that 14C from administered 2-[14C )acetone was principally located in carbons 1, 2, 5, and 6 of the glucose molecule in five of six patients. This distribution is similar to that expected from 2-[14C]pyruvate, suggesting that acetone was converted to glucose through pyruvate. In one patient, label was located predominantly in glucose carbons 3 and 4, indicating that acetone metabolism may be different in some patients. Acetol (1-hydroxyacetone) and 1,2-propanediol (PPD), two possible metabolites of acetone, were detected in plasma of the patients. The concentrations of Acetol ranged from 0 to 0.48 mM and of PPD ranged from 0 to 0.53 mM. The concentrations of each metabolite were directly related to the plasma acetone concentrations. During the continuous infusion of 2-[14C]acetone, the specific activities of plasma glucose and PPD rose continuously but did not reach constant values. Estimates of the minimal percent plasma glucose and PPD derived from plasma acetone averaged 2.1 and 74%, respectively.

Hydroxylation of acetone by ethanol- and acetone-inducible cytochrome P-450 in liver microsomes and reconstituted membranes

Acetone oxidation in rat liver microsomes was induced 5- or 8-fold by the treatment of the animals with ethanol or acetone, respectively. The apparent K m of the reaction was 0.9 mM, a value lower than the concentration reported for plasma acetone under starvation conditions. The major acetone metabolite was identified as acetol by GC-MS. Acetone oxidation in microsomes was inhibited by typical P-450 inhibitors as well as by compounds (e.g. imidazole) known to interact with the ethanol-inducible P-450 form. Antibodies against this P-450 isozyme were inhibitory for the reaction in rabbit liver microsomes and this isozyme was the only one that showed acetone hydroxylation activity in reconstituted membranes. Imidazole inhibited the conversion of [ 14C]acetone into low- M r compounds (e.g. glucose) in vivo. It is suggested that the ethanol-and acetone-inducible P-450 make use of acetone as an endogenous substrate in the utilization of the compound for, e.g. glucose production under conditions of starvation and diabetic ketoacidosis.

Gluconeogenesis from acetone in starved rats.

To non-anaesthetized rats starved for 3 days, [U-14C]acetone, NaH14CO3, L-[U-14C]lactate, [2-14C]acetate or D-[U-14C]- plus D-[3-3H]-glucose was injected intravenously. From the change in the plasma concentration of labelled acetone versus time after the injection, the metabolic clearance rate of acetone was calculated as 2.25 ml/min per kg body wt., and its rate of turnover as 0.74 mumol/min per kg. The extent and time course of the labelling of plasma glucose, lactate, urea and acetoacetate were followed and compared with those observed after the injection of labelled lactate, acetate and NaHCO3. The labelling of plasma lactate was rapid and extensive. Some 1.37% of the 14C atoms of circulating glucose originated from plasma acetone, compared with 44% originating from lactate. By deconvolution of the Unit Impulse Response Function of glucose, it was shown that the flux of C atoms from acetone to glucose reached a peak at about 100 min after injection of labelled acetone. In comparable experiments the transfer from lactate reached a peak at 14 min after the injection of labelled lactate. It was concluded that acetone is converted into lactate to a degree sufficient to account for the labelling of plasma glucose and is thus a true, albeit minor, substrate of glucose synthesis in starved rats.

On the identity of bovine seminal plasma inhibin

In light of current discussions on multiple forms of inhibin, it was thought of interest to ascertain the identity of the postulated ‘iso-hormones’ of bull seminal plasma inhibin (Chari et al., 1978). By subjecting the biologically active fraction, obtained by Sephadex G-100 gel filtration of bull seminal plasma acetone powder, to extensive dialysis in distilled water adjusted to pH 5.8, it was possible to remove the bulk of inert protein as a precipitate. The resulting active preparation could be readily fractionated by preparative iso-electric focusing in the pH range 4.0–6.5 yielding 2 distinct homogeneous peptides, α and β, capable of suppressing hCG-induced uterine weight increase in immature mice, in a ‘reversed Steelman-Pohley’ assay design. However, of these, a alone was able to suppress post-castrational serum gonadotropin rise in appropriate animal models. This peptide is highly acidic in nature (iso-electric point = 2.2) and has a molecular weight ( M r ) of 18200 and a Stokes radius of 1.90 nm. On the basis of currently available evidence, it is concluded that the molecule consists of a single peptide chain.

Determination of acetoacetate in plasma by a combination of enzymatic decarboxylation and head-space gas chromatography.

Acetoacetate concentration in plasma was determined by head-space gas chromatography after decarboxylation by the use of acetoacetate decarboxylase, which was recently isolated from Bacillus polymyxa A-57 strain. Partial purification of acetoacetate decarboxylase solution was carried out by DEAE-cellulose column chromatography of the cell-free extract, which was prepared by ultrasonication. The properties of the enzyme were found to be particularly suitable for acetoacetate assay (optimum pH, 5.8 ; Vmax, 230μmol/min/mg ; Km, 5.9×10-4M). Plasma was deproteinized by Somogyi's method. Acetone in the mildly basic supernatant was assayed by head-space gas chromatography. Acetoacetate was calculated by subtracting blank acetone from total acetone after enzymatic decarboxylation of acetoacetate. The minimal detectable concentration was 1μM. This method gave better reproducibility (CV=2.0-8.0%) and recovery (96.0-101.8%) than chemical decarboxylation with perchloric acid. Normal subjects (n=31) showed plasma acetone levels of 7.2±3.4μM and acetoacetate levels of 22.5±9.7μM. Diabetic patients (n=44), treated by diet control alone without drug therapy, gave plasma acetone levels of 8.1±3.5μM and acetoacetate levels of 25.0±8.0μM. There was no significant difference between the two groups.

Acetone metabolism during diabetic ketoacidosis.

The presence and the importance of acetone and its metabolism in diabetic ketoacidosis has largely been ignored. Therefore, we studied acetone metabolism in nine diabetic patients in moderate to severe ketoacidosis. The concentration of acetone in plasma, urine, and breath, and the rates of acetone production and elimination in breath and urine were determined and the rates of vivo metabolism were calculated. Plasma acetone concentrations (1.55-8.91 mM) were directly related and were generally greater than acetoacetate concentrations (1.16-6.08 mM). The rates of acetone production ranged from 68 to 581 mumol/min/1.73 m2, indicating the heterogeneous nature of the patients studied. The average acetone production rate was 265 mumol/min/1.73 m2 and accounted for about 52% of the estimated acetoacetate production rate. Urinary excretion of acetone remained constant and accounted for about 7% of the acetone production rate in all patients. There was a positive linear relationship between the percentage of the acetone production rate accounted for by excretion in breath and the plasma acetone concentration. At low plasma acetone concentrations, approximately 20%, and at high plasma acetone concentrations, approximately 80% of the production rate was accounted for by breath acetone. In contrast, there was a negative linear relationship between the percentage of acetone production rate undergoing in vivo metabolism and plasma acetone concentration. At low plasma acetone concentrations, approximately 75%, and at high concentrations, approximately 20% of acetone production rate was accounted for by in vivo metabolism. Radioactivity from 2-[14C]-acetone was variably present in plasma acetone, glucose, lipids and proteins. No radioactivity was found in plasma acetoacetate, beta-hydroxy butyrate or free fatty acids or other anionic compounds. Exchange rates of acetone into other metabolites could not be estimated because of non-steady-state precursor product relationships in these patients.

Plasma Acetone Metabolism in the Fasting Human

The metabolism of acetone was studied in lean and obese humans during starvation ketosis. Acetone concentrations in plasma, urine, and breath; and rates of endogenous production, elimination in breath and urine, and in vivo metabolism were determined. There was a direct relationship between plasma acetone turnover (20-77 mumol/m(2) per min) and concentration (0.19-1.68 mM). Breath and urinary excretion of acetone accounted for a 2-30% of the endogenous production rate, and in vivo metabolism accounted for the remainder. Plasma acetone oxidation accounted for congruent with60% of the production rate in 3-d fasted subjects and about 25% of the production rate in 21-d fasted subjects. About 1-2% of the total CO(2) production was derived from plasma acetone oxidation and was not related to the plasma concentration or production rate. Radioactivity from [(14)C]acetone was not detected in plasma free fatty acids, acetoacetate, beta-hydroxybutyrate, or other anionic compounds, but was present in plasma glucose, lipids, and proteins. If glucose synthesis from acetone is possible in humans, this process could account for 11% of the glucose production rate and 59% of the acetone production rate in 21-d fasted subjects. During maximum acetonemia, acetone production from acetoacetate could account for 37% of the anticipated acetoacetate production, which implies that a significant fraction of the latter compound does not undergo immediate terminal oxidation.

Effect of nutrition on species of lipoprotein lipase

When NH 4OH-NH 4Cl extracts of heart and post-heparin plasma acetone powder were applied to agarose gel chromatographic columns, two peaks of lipoprotein lipase activity were eluted from the heart extract but only a single peak from that of plasma. The two activities from heart showed elution volumes similar to those previously determined for the two lipoprotein lipase species of adipose tissue. The elution volume of the plasma species approximated that of the larger of the adipose tissue species. The effect of nutritional state on these lipoprotein lipase species was studied in fasted and refed rats. Refeeding increased the activity of the two species in adipose tissue and decreased both heart species. The single species in post-heparin plasma was unaffected by these nutritional conditions.

The rapid determination of acetone in breath and plasma

A gas-chromatographic method for the determination of acetone is described. The technique is rapid and easy to perform and is applicable to serial measurements of acetone in breath and plasma using the same column packing. The method of breath sampling has been adapted for clinical use at the bedside and is suitable for studies on diabetic patients with hyperketonaemia. This method for plasma acetone determination compares favourably with an established chemical method.

Body fluid ketones related to fasting, diabetes, and tests of blood glucose tolerance

Head space sampling over biological fluids for gas chromatographic analysis provides a rapid, reliable method for measuring volatile materials at trace levels. Its usefulness is shown by monitoring changes in fluid ketones during fasting and during blood glucose tolerance tests. Blood and urine acetone levels are reported for diabetics. Acetone, butanone, and 2-pentanone increased in blood and urine of fasting subjects. These changes are plotted for five adults during 40 hours of fasting. Similar plots were made for three children during a 27-hour fast. Changes in blood and urine acetone concentrations during blood glucose tolerance tests of 14 individuals were observed. Plasma acetone levels dropped by about 40% at the 2-hour glucose tolerance sample but were back to normal at 4 hours. Urine acetone levels continued to decrease even up to 4 hours after administration of glucose. Diabetic blood and urine ketone pictures were similar to those for fasting individuals.

Clinical value of a simple qualitative test for plasma acetone in diabetic coma.

Clinical value of a simple qualitative test for plasma acetone in diabetic coma.