Mette G B Pedersen, Nikolaj Rittig, Maj Bangshaab, Kristoffer Berg-Hansen, Nigopan Gopalasingam, Lars C Gormsen, Esben Søndergaard, Niels Møller
{"title":"Effects of exogenous lactate on lipid, protein, and glucose metabolism-a randomized crossover trial in healthy males.","authors":"Mette G B Pedersen, Nikolaj Rittig, Maj Bangshaab, Kristoffer Berg-Hansen, Nigopan Gopalasingam, Lars C Gormsen, Esben Søndergaard, Niels Møller","doi":"10.1152/ajpendo.00301.2023","DOIUrl":null,"url":null,"abstract":"<p><p>Lactate may inhibit lipolysis and thus enhance insulin sensitivity, but there is a lack of metabolic human studies. This study aimed to determine how hyperlactatemia affects lipolysis, glucose- and protein metabolism, and insulin sensitivity in healthy men. In a single-blind, randomized, crossover design, eight healthy men were studied after an overnight fast on two occasions: <i>1</i>) during a sodium-lactate infusion (LAC) and <i>2</i>) during a sodium-matched NaCl infusion (CTR). Both days consisted of a 3-h postabsorptive period followed by a 3-h hyperinsulinemic-euglycemic clamp (HEC). Lipolysis rate, endogenous glucose production (EGP), and delta glucose rate of disappearance (ΔRd<sub>glu</sub>) were evaluated using [9,10-<sup>3</sup>H]palmitate and [3-<sup>3</sup>H]glucose tracers. In addition, whole body- and forearm protein metabolism was assessed using [<sup>15</sup>N]phenylalanine, [<sup>2</sup>H<sub>4</sub>]tyrosine, [<sup>15</sup>N]tyrosine, and [<sup>13</sup>C]urea tracers. In the postabsorptive period, plasma lactate increased to 2.7 ± 0.5 mmol/L during LAC vs. 0.6 ± 0.3 mmol/L during CTR (<i>P</i> < 0.001). In the postabsorptive period, palmitate flux was 30% lower during LAC compared with CTR (84 ± 32 µmol/min vs. 120 ± 35 µmol/min, <i>P</i> = 0.003). During the HEC, palmitate flux was suppressed similarly during both interventions (<i>P</i> = 0.7). EGP, ΔRd<sub>glu</sub>, and <i>M</i> value were similar during LAC and CTR. During HEC, LAC increased whole body phenylalanine flux (<i>P</i> = 0.02) and protein synthesis (<i>P</i> = 0.03) compared with CTR; LAC did not affect forearm protein metabolism compared with CTR. Lactate infusion inhibited lipolysis by 30% under postabsorptive conditions but did not affect glucose metabolism or improve insulin sensitivity. In addition, whole body phenylalanine flux was increased. Clinical trial registrations: NCT04710875.<b>NEW & NOTEWORTHY</b> Lactate is a decisive intermediary metabolite, serving as an energy substrate and a signaling molecule. The present study examines the effects of lactate on substrate metabolism and insulin sensitivity in healthy males. Hyperlactatemia reduces lipolysis by 30% without affecting insulin sensitivity and glucose metabolism. In addition, hyperlactatemia increases whole body amino acid turnover rate.</p>","PeriodicalId":7594,"journal":{"name":"American journal of physiology. Endocrinology and metabolism","volume":null,"pages":null},"PeriodicalIF":4.2000,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11193511/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"American journal of physiology. Endocrinology and metabolism","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1152/ajpendo.00301.2023","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/2/7 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"ENDOCRINOLOGY & METABOLISM","Score":null,"Total":0}
引用次数: 0
Abstract
Lactate may inhibit lipolysis and thus enhance insulin sensitivity, but there is a lack of metabolic human studies. This study aimed to determine how hyperlactatemia affects lipolysis, glucose- and protein metabolism, and insulin sensitivity in healthy men. In a single-blind, randomized, crossover design, eight healthy men were studied after an overnight fast on two occasions: 1) during a sodium-lactate infusion (LAC) and 2) during a sodium-matched NaCl infusion (CTR). Both days consisted of a 3-h postabsorptive period followed by a 3-h hyperinsulinemic-euglycemic clamp (HEC). Lipolysis rate, endogenous glucose production (EGP), and delta glucose rate of disappearance (ΔRdglu) were evaluated using [9,10-3H]palmitate and [3-3H]glucose tracers. In addition, whole body- and forearm protein metabolism was assessed using [15N]phenylalanine, [2H4]tyrosine, [15N]tyrosine, and [13C]urea tracers. In the postabsorptive period, plasma lactate increased to 2.7 ± 0.5 mmol/L during LAC vs. 0.6 ± 0.3 mmol/L during CTR (P < 0.001). In the postabsorptive period, palmitate flux was 30% lower during LAC compared with CTR (84 ± 32 µmol/min vs. 120 ± 35 µmol/min, P = 0.003). During the HEC, palmitate flux was suppressed similarly during both interventions (P = 0.7). EGP, ΔRdglu, and M value were similar during LAC and CTR. During HEC, LAC increased whole body phenylalanine flux (P = 0.02) and protein synthesis (P = 0.03) compared with CTR; LAC did not affect forearm protein metabolism compared with CTR. Lactate infusion inhibited lipolysis by 30% under postabsorptive conditions but did not affect glucose metabolism or improve insulin sensitivity. In addition, whole body phenylalanine flux was increased. Clinical trial registrations: NCT04710875.NEW & NOTEWORTHY Lactate is a decisive intermediary metabolite, serving as an energy substrate and a signaling molecule. The present study examines the effects of lactate on substrate metabolism and insulin sensitivity in healthy males. Hyperlactatemia reduces lipolysis by 30% without affecting insulin sensitivity and glucose metabolism. In addition, hyperlactatemia increases whole body amino acid turnover rate.
期刊介绍:
The American Journal of Physiology-Endocrinology and Metabolism publishes original, mechanistic studies on the physiology of endocrine and metabolic systems. Physiological, cellular, and molecular studies in whole animals or humans will be considered. Specific themes include, but are not limited to, mechanisms of hormone and growth factor action; hormonal and nutritional regulation of metabolism, inflammation, microbiome and energy balance; integrative organ cross talk; paracrine and autocrine control of endocrine cells; function and activation of hormone receptors; endocrine or metabolic control of channels, transporters, and membrane function; temporal analysis of hormone secretion and metabolism; and mathematical/kinetic modeling of metabolism. Novel molecular, immunological, or biophysical studies of hormone action are also welcome.