Lactate Supplementation Research Articles

Effect of lactate supplementation on V̇O<sub>2peak</sub> and onset of blood lactate accumulation: A double-blind, placebo-controlled trial

Background: Professional and recreational athletes use ergogenic aids to enhance aerobic performance, facilitate training adaptations, and reduce recovery time. While the ergogenic effect of commonly marketed and commercially available ergogenic aids (i.e., sodium bicarbonate and β-alanine) have been investigated extensively, the effectiveness of lactate supplementation on aerobic capacity markers (i.e., V̇O2peak and the onset blood lactate accumulation) has not been thoroughly investigated. Objective: The purpose of this study was to examine the effect of lactate supplementation on V̇O2peak and the onset blood lactate accumulation (OBLA). Methods: Eighteen healthy individuals (14 men and 4 women, age: 24 ± 5 years, height: 171 ± 7 cm, body mass: 76 ± 17 kg) participated in a double-blind-placebo-controlled study and were randomly assigned to one of 2 groups: placebo (PLA, n = 8), or supplement (SUP, n = 10) consisting of a combination of magnesium lactate dihydrate and calcium lactate monohydrate. Prior to and following supplementation, participants performed a cycling graded exercise test to determine V̇O2peak, time to exhaustion, power output, V̇O2 and % V̇O2peak associated with OBLA. Results: There were no statistically significant differences between PLA and SUP in direct markers of aerobic capacity (all p > .05). Heart rate at OBLA was reduced by 6 ± 6% in the PLA group post-supplementation compared to pre-supplementation (p = .03).Conclusions: Lactate supplementation did not present an advantage over a placebo in improving aerobic capacity. The results from this study support those by previous investigators suggesting that there is no physiological rationale for using lactate supplementation to improve aerobic capacity and/or performance.

Pyruvate Homeostasis as a Determinant of Parasite Growth and Metabolic Plasticity in Toxoplasma gondii.

Toxoplasma gondii is a widespread intracellular pathogen infecting humans and a variety of animals. Previous studies have shown that Toxoplasma uses glucose and glutamine as the main carbon sources to support asexual reproduction, but neither nutrient is essential. Such metabolic flexibility may allow it to survive within diverse host cell types. Here, by focusing on the glycolytic enzyme pyruvate kinase (PYK) that converts phosphoenolpyruvate (PEP) into pyruvate, we found that Toxoplasma can also utilize lactate and alanine. We show that catabolism of all indicated carbon sources converges at pyruvate, and maintaining a constant pyruvate supply is critical to parasite growth. Toxoplasma expresses two PYKs: PYK1 in the cytosol and PYK2 in the apicoplast (a chloroplast relict). Genetic deletion of PYK2 did not noticeably affect parasite growth and virulence, which contrasts with the current model of carbon metabolism in the apicoplast. On the other hand, PYK1 was refractory to disruption. Conditional depletion of PYK1 resulted in global alteration of carbon metabolism, amylopectin accumulation, and reduced cellular ATP, leading to severe growth impairment. Notably, the attenuated growth of the PYK1-depleted mutant was partially rescued by lactate or alanine supplementation, and rescue by lactate required lactate dehydrogenase activity to convert it to pyruvate. Moreover, depletion of PYK1 in conjunction with PYK2 ablation led to accentuated loss of apicoplasts and complete growth arrest. Together, our results underline a critical role of pyruvate homeostasis in determining the metabolic flexibility and apicoplast maintenance, and they significantly extend our current understanding of carbon metabolism in T. gondiiIMPORTANCEToxoplasma gondii infects almost all warm-blooded animals, and metabolic flexibility is deemed critical for its successful parasitism in diverse hosts. Glucose and glutamine are the major carbon sources to support parasite growth. In this study, we found that Toxoplasma is also competent in utilizing lactate and alanine and, thus, exhibits exceptional metabolic versatility. Notably, all these nutrients need to be converted to pyruvate to fuel the lytic cycle, and achieving a continued pyruvate supply is vital to parasite survival and metabolic flexibility. Although pyruvate can be generated by two distinct pyruvate kinases, located in cytosol and apicoplast, respectively, the cytosolic enzyme is the main source of subcellular pyruvate, and cooperative usage of pyruvate among multiple organelles is critical for parasite growth and virulence. These findings expand our current understanding of carbon metabolism in Toxoplasma gondii and related parasites while providing a basis for designing novel antiparasitic interventions.

The effect of concentrate supplementation type on milk production, dry matter intake, rumen fermentation, and nitrogen excretion in late-lactation, spring-calving grazing dairy cows

In Ireland, milk is primarily produced using a spring-calving grass-based system, with the use of concentrate supplementation mainly when pasture availability and quality are reduced. In the autumn, when cows are in late lactation, reduced pasture productivity results in reduced milk yield and altered milk composition. Nitrogen utilization efficiency also reduces as lactation progresses. Concentrate supplementation has been found to increase milk production and reduce nitrogen (N) excretion, as high-N grass is usually replaced by a lower-N supplement; however, there is a paucity of information with regard to the optimum type of supplementation in late lactation. Therefore, the objective of this research is to investigate the effect of different concentrate supplementation types, based on barley or maize, on milk production, dry matter intake (DMI), rumen fermentation, and N excretion in late-lactation, spring-calving, grazing dairy cows. Thirty-six Holstein Friesian dairy cows were blocked on days in milk (185 DIM) and balanced for parity, pre-experimental milk yield, milk composition, and body condition score. Cows were randomly assigned to 1 of 3 dietary treatments in a randomized complete block design (n = 12). The 3 treatments consisted of a perennial ryegrass-based pasture-only (PO) treatment and pasture plus either of 2 supplementary concentrates, based on barley (PB) or maize (PM). The diets were fed for a 14-d acclimatization period and then for a further 63-d experimental period. Cows offered PO had a lower daily milk yield (15.1 kg) than PB (18.2 kg) or PM (16.8 kg). Similarly, PO had lower daily milk solids yield (1.46 kg) than PB or PM (1.68 and 1.53 kg, respectively). Cows offered PB had a greater milk yield and higher fat and protein yields than those offered PM. Offering PB increased total DMI (19.5 kg) compared with PO (17.7 kg), and milk response to concentrates was also greater for PB compared with PM (1.21 vs. 0.71 kg of milk per kg of concentrate). Cows offered PB had increased N in milk compared with PO. In conclusion, concentrate supplementation based on barley or maize resulted in increased milk and milk solids yield compared with offering PO. Cows offered barley had a greater response to concentrates and increased milk and milk solids yield in comparison to maize and showed increased N partitioning in milk compared with PO. A barley-based concentrate increased total DMI compared with PO.

Vitamin D Supplementation in Pregnancy and Lactation and Infant Growth

(Abstracted from N Engl J Med 2018;379:535–546) It is unclear whether maternal vitamin D supplementation during pregnancy and lactation improves fetal and infant growth in regions where vitamin D deficiency is common.

Effect of Calcium Consumption on the Spasticity in the Spastic Rats

Spasticity is a stiff muscle condition because the muscles receive impulses continuously. Calcium ions play a role in the ability of nerves to stimulate muscle contraction. This study aimed to analyze the effect of calcium consumption on the changes of spasticity and the relation of calcium levels in the blood and muscle to the spasticity. The experimental study was conducted on 42 male Sprague-Dawley rats aged 12 - 14 weeks. The 15-d intervention was conducted on six groups of spastic rats by administering 20 g of feed containing 50 mg, 100 mg, and 200 mg of calcium, it also received 100 mg, 200 mg, and 300 mg of calcium lactate supplementation. The experimental rats were induced with 80 mg/kg BW of Erythrocin B through the tail vein to make them spastic. This study showed a tendency of increased spasticity along with the increased dose of calcium given to the subjects. There were significant differences (p = 0.007) in changes in spasticity between groups. The significant differences (p = 0.02) in changes in blood calcium levels. The Spearman’s correlations test on the changes in blood calcium levels and changes in spasticity showed a positive coefficient correlation (r = 0.097) with a p-value of 0.54. An increase in blood calcium levels and a large decrease in spasticity were found in the group receiving 100 mg calcium intake in 20 g of feed. The calcium levels in muscles had a significant correlation with spasticity (p = 0.038, r = 0.810). The calcium levels in the muscle had a strong correlation with blood calcium levels (p = 0.041, r = 0.748). The biggest decrease in spasticity occurred after 100 mg of calcium were given to the rats for 15 days, and it was considered as an optimal dose. The calcium levels in the muscles had a strong correlation with blood calcium levels and the spasticity of the spastic rats.

Vitamin D During Pregnancy and Infant Growth: A Long Shot

Research Article| December 01 2018 Vitamin D During Pregnancy and Infant Growth: A Long Shot AAP Grand Rounds (2018) 40 (6): 69. https://doi.org/10.1542/gr.40-6-69 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation Vitamin D During Pregnancy and Infant Growth: A Long Shot. AAP Grand Rounds December 2018; 40 (6): 69. https://doi.org/10.1542/gr.40-6-69 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search toolbar search search input Search input auto suggest filter your search All PublicationsAll JournalsAAP Grand RoundsPediatricsHospital PediatricsPediatrics In ReviewNeoReviewsAAP NewsAll AAP Sites Search Advanced Search Source: Roth DE, Morris SK, Zlotkin S, et al. Vitamin D supplementation in pregnancy and lactation and infant growth. N Engl J Med. 2018; 379(6): 535– 546; doi: https://doi.org/10.1056/NEJMoa1800927Google Scholar Investigators from multiple institutions conducted a randomized controlled trial to determine the efficacy of maternal vitamin D supplementation (VDS) on infant growth in regions where vitamin D deficiency is common. Participants were healthy pregnant women living in Bangladesh who were 17–24 weeks’ gestation. At enrollment, participants were randomized to 1 of 5 groups, based on receipt of (a) a placebo tablet through the prenatal period and for 26 weeks postpartum, (b) prenatal VDS only at 4,200 IU/week, (c) prenatal VDS only at 16,800 IU/week, (d) prenatal VDS only at 28,000 IU/week, and (e) prenatal VDS at 28,000 IU/week and postpartum VDS at 28,000 IU/week for 26 weeks. All tablets were identical in taste and appearance, and they were administered under direct observation when possible. Demographic data and maternal serum 25-hydroxyvitamin D concentrations were collected at baseline, with vitamin D deficiency defined as 25-hydroxyvitamin D concentrations <30 nmol/L. The primary outcome was infant length-for-age z score at 1 year of age, defined as the mean of 2 independent measurements performed by trained study personnel plotted on WHO child growth standards. Secondary outcomes included confirmed maternal hypercalcemia, defined as a serum calcium concentration of >2.6 mmol/L on a repeat specimen or >2.8 mmol/L on a single specimen at enrollment through 6 months postpartum. Other secondary outcomes included other infant anthropomorphic measures at 1 year of age, infant serum 25-hydroxyvitamin D concentrations at 3, 6, and 12 months of age, and maternal serum 25-hydroxyvitamin D concentrations at delivery and 3 and 6 months postpartum. Investigators used t-tests and compared outcomes across groups using an intention-to-treat analysis. There were 1,300 participants enrolled and randomized to the 5 groups. Baseline characteristics, including baseline maternal 25-hydroxyvitamin D levels, were not significantly different across groups. Overall, 64% of participants were vitamin D deficient at baseline. There was no significant difference in infant length-for-age z scores at 1 year across the 5 groups (P=0.23). There were also no significant differences in other infant anthropomorphic measures at 1 year of age across treatment groups. There was a significant, dose-dependent effect in maternal and infant 25-hydroxyvitamin D concentrations, with infants and mothers in the fifth group having the highest concentrations. There was confirmed maternal hypercalcemia in 0.7% of participants, but frequencies did not differ significantly by group. The investigators conclude that maternal VDS does not improve infant growth in a population with widespread vitamin D deficiency. Dr Chung has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device. Vitamin D deficiency is a global health problem; some countries in the Middle East and South Asia have vitamin D deficiency prevalence rates... You do not currently have access to this content.

Hypertonic Lactate to Improve Cerebral Perfusion and Glucose Availability After Acute Brain Injury*

Lactate promotes cerebral blood flow and is an efficient substrate for the brain, particularly at times of glucose shortage. Hypertonic lactate is neuroprotective after experimental brain injury; however, human data are limited. Prospective study (clinicaltrials.gov NCT01573507). Academic ICU. Twenty-three brain-injured subjects (13 traumatic brain injury/10 subarachnoid hemorrhage; median age, 59 yr [41-65 yr]; median Glasgow Coma Scale, 6 [3-7]). Three-hour IV infusion of hypertonic lactate (sodium lactate, 1,000 mmol/L; concentration, 30 µmol/kg/min) administered 39 hours (26-49 hr) from injury. We examined the effect of hypertonic lactate on cerebral perfusion (using transcranial Doppler) and brain energy metabolism (using cerebral microdialysis). The majority of subjects (13/23 = 57%) had reduced brain glucose availability (baseline pretreatment cerebral microdialysis glucose, < 1 mmol/L) despite normal baseline intracranial pressure (10 [7-15] mm Hg). Hypertonic lactate was associated with increased cerebral microdialysis lactate (+55% [31-80%]) that was paralleled by an increase in middle cerebral artery mean cerebral blood flow velocities (+36% [21-66%]) and a decrease in pulsatility index (-21% [13-26%]; all p < 0.001). Cerebral microdialysis glucose increased above normal range during hypertonic lactate (+42% [30-78%]; p < 0.05); reduced brain glucose availability correlated with a greater improvement of cerebral microdialysis glucose (Spearman r = -0.53; p = 0.009). No significant changes in cerebral perfusion pressure, mean arterial pressure, systemic carbon dioxide, and blood glucose were observed during hypertonic lactate (all p > 0.1). This is the first clinical demonstration that hypertonic lactate resuscitation improves both cerebral perfusion and brain glucose availability after brain injury. These cerebral vascular and metabolic effects appeared related to brain lactate supplementation rather than to systemic effects.

Vitamin D Supplementation in Pregnancy and Lactation and Infant Growth

BackgroundIt is unclear whether maternal vitamin D supplementation during pregnancy and lactation improves fetal and infant growth in regions where vitamin D deficiency is common.MethodsWe conducted a randomized, double-blind, placebo-controlled trial in Bangladesh to assess the effects of weekly prenatal vitamin D supplementation (from 17 to 24 weeks of gestation until birth) and postpartum vitamin D supplementation on the primary outcome of infants’ length-for-age z scores at 1 year according to World Health Organization (WHO) child growth standards. One group received neither prenatal nor postpartum vitamin D (placebo group). Three groups received prenatal supplementation only, in doses of 4200 IU (prenatal 4200 group), 16,800 IU (prenatal 16,800 group), and 28,000 IU (prenatal 28,000 group). The fifth group received prenatal supplementation as well as 26 weeks of postpartum supplementation in the amount of 28,000 IU (prenatal and postpartum 28,000 group).ResultsAmong 1164 infants assessed at 1 year of age (89.5% of 1300 pregnancies), there were no significant differences across groups in the mean (±SD) length-for-age z scores. Scores were as follows: placebo, −0.93±1.05; prenatal 4200, −1.11±1.11; prenatal 16,800, −0.98±0.97; prenatal 28,000, −1.06±1.07; and prenatal and postpartum 28,000, −0.94±1.00 (P=0.25 for a global test of differences across groups). Other anthropometric measures, birth outcomes, and morbidity did not differ significantly across groups. Vitamin D supplementation had expected effects on maternal and infant serum 25-hydroxyvitamin D and calcium concentrations, maternal urinary calcium excretion, and maternal parathyroid hormone concentrations. There were no significant differences in the frequencies of adverse events across groups, with the exception of a higher rate of possible hypercalciuria among the women receiving the highest dose.ConclusionsIn a population with widespread prenatal vitamin D deficiency and fetal and infant growth restriction, maternal vitamin D supplementation from midpregnancy until birth or until 6 months post partum did not improve fetal or infant growth. (Funded by the Bill and Melinda Gates Foundation; ClinicalTrials.gov number, NCT01924013.)

Investigation of ammonium lactate supplementation on fermentation end products and bacterial assimilation of nitrogen in dual-flow continuous culture

Supplements investigated throughout the present study are produced by fermenting lactose that is present in whey to lactate, yielding products differing in ammonium relative to lactate concentrations and in physical form (liquid or dry). Trials 1 and 2 investigated Lacto-Whey (LW; Fermented Nutrition Corp., Luxemburg, WI) and GlucoBoost (GB; Fermented Nutrition Corp.), respectively, using dual-flow continuous culture systems (n = 4), each with a 4 × 4 Latin square design. A greater proportion of nonprotein nitrogen was present in GB than in LW. In trial 1, the treatment with LW was isonitrogenously dosed against soybean meal (SBM) as a control (no LW) and factorialized with either a wheat- or corn-based concentrate (55% inclusion rate, dry matter basis). We hypothesized that LW would increase propionate production and that the combination of +LW with wheat would increase bacterial assimilation of NH3-N into cellular N. No differences were observed for total volatile fatty acid (VFA) production per day. However, treatment × time interactions revealed that +LW increased lactate concentration at 0, 0.5, and 1 h and tended to increase molar percentage of propionate at 1 and 1.5 h postfeeding, documenting the immediate availability of lactate converted to propionate in the +LW treatments. The main effect of corn increased the proportion of bacterial N derived from NH3-N. Trial 2 was designed to investigate GB; isonitrogenous treatments included an SBM control, crystal GB, liquid GB (LGB), and LGB with yeast culture, which were dosed twice daily. We hypothesized that GB would increase propionate production and bacterial assimilation of NH3-N; the combination of LGB and yeast culture was expected to have a positive additive effect, yielding the greatest VFA production and bacterial NH3-N assimilation. No differences were observed for total VFA production; however, LGB decreased molar percentage of acetate and increased propionate and butyrate molar percentages. There were no differences in non-NH3-N flow or microbial N flow. Under the conditions of our studies, lactate in LW and GB was fermented extensively to propionate, and microbial protein synthesis in these treatments was comparable with that in SBM controls.

Abstract 4969: Autophagy modulates lipid metabolism to support Liver Kinase B1 (LKB1) - deficient lung tumor growth

Abstract Autophagy degrades and recycles macromolecules for cells to survive starvation. In genetically engineered mouse models (GEMMs) for human non-small cell lung cancer (NSCLC), autophagy supports Kras-driven lung tumor growth with or without Trp53. Tumor suppressor liver kinase B1 (LKB1) activates 5'-adenosine monophosphate protein kinase (AMPK) to maintain energy homeostasis. LKB1 mutations are detected in 20-30% of NSCLC, causing aggressive tumor growth and resistance to chemotherapy. Identifying novel target to improve LKB1-deficient tumor treatment is urgently needed. Using GEMMs for NSCLC with oncogenic Kras and LKB1 loss (KL), we found that autophagy deficiency increased the survival of the mice bearing Atg7-/- tumors compared to mice bearing wild-type (WT) tumors. To determine the mechanism of autophagy in supporting LKB1-deficient Kras-driven lung tumor growth, tumor derived cell lines (TDCLs) were generated from the lung tumors of these mice. We found that Atg7 null TDCLs were more sensitive to glucose and glutamine deprivation-induced cell death compared to Atg7 WT TDCLs. Atg7 null TDCLs were also more sensitive to starvation-induced cell death than Atg7 WT TDCLs, which can be rescued by glucose, glutamine, pyruvate, lactate and nucleotide supplementation. Thus, autophagy is required for KL TDCLs to tolerate metabolic stress. Furthermore, we observed that palmitate supplementation successfully rescued starvation-induced Atg7 null TDCLs death, indicating that autophagy is required to maintain free fatty acid level for cells to survive starvation. We further performed metabolomics in TDCLs in normal and starvation conditions and found that level of amino acids and intermediates for glycolysis and TCA cycle metabolism were significantly lower in Atg7 null TDCLs compared to Atg7 WT TDCLs during HBSS starvation. Surprisingly, we observed a significant increase in the levels of biotin, a precursor for fatty acid synthesis, in Atg7 null TDCLs than that in WT TDCLs, indicating that accumulation of biotin in autophagy deficient cells might be due to defective fatty acid synthesis. In support of this, we found that the lipid droplets accumulation is significantly lower in Atg7 null KL TDCLs than that in Atg7 WT cells. To further evaluate the functional consequences of autophagy-mediated lipid metabolism in supporting KL tumor growth, we treated Atg7 null and WT cells with etomoxir, an irreversible inhibitor of carnitine palmitoyltransferase-1 (CPT-1) to inhibit fatty acid oxidation, in normal and starvation conditions. We found that Atg7 null TDCLs are much more sensitive to etomoxir treatment than WT cells. Taken together, autophagy plays a critical role in supporting lipid metabolism for cells to survive metabolic stress. Thus, a combination of autophagy inhibition with interruption of lipid metabolism could be a novel therapeutic strategy to treat LKB1-deficient lung tumor. Citation Format: Vrushank D. Bhatt, Zhixian Hu, Xiaoyang Su, Jessie Yanxiang Guo. Autophagy modulates lipid metabolism to support Liver Kinase B1 (LKB1) - deficient lung tumor growth [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4969.

Management of Pregnant Women after Bariatric Surgery.

The prevalence of obesity is growing worldwide, and strategies to overcome this epidemic need to be developed urgently. Bariatric surgery is a very effective treatment option to reduce excess weight and often performed in women of reproductive age. Weight loss influences fertility positively and can resolve hormonal imbalance. So far, guidelines suggest conceiving after losing maximum weight and thus recommend conception at least 12–24 months after surgery. As limited data of these suggestions exist, further evidence is urgently needed as well for weight gain in pregnancy. Oral glucose tolerance tests for the diagnosis of gestational diabetes mellitus (GDM) should not be performed after bariatric procedures due to potential hypoglycaemic adverse events and high variability of glucose levels after glucose load. This challenges the utility of the usual diagnostic criteria for GDM in accurate prediction of complications. Furthermore, recommendations on essential nutrient supplementation in pregnancy and lactation in women after bariatric surgery are scarce. In addition, nutritional deficiencies or daily intake recommendations in pregnant women after bariatric surgery are not well investigated. This review summarizes current evidence, proposes clinical recommendations in pregnant women after bariatric surgery, and highlights areas of lack of evidence and the resulting urgent need for more clinical investigations.

Autophagy modulates lipid metabolism to support Liver Kinase B1 (LKB1)‐deficient lung tumor growth

Autophagy degrades and recycles macromolecules for cells to survive starvation. In genetically engineered mouse models (GEMMs) for human non‐small cell lung cancer (NSCLC), autophagy supports Kras‐driven lung tumor growth with or without Trp53. Tumor suppressor liver kinase B1 (LKB1) activates 5′‐adenosine monophosphate protein kinase (AMPK) to maintain energy homeostasis. LKB1 mutations are detected in 20–30% of NSCLC, causing aggressive tumor growth and resistance to chemotherapy. Identifying novel target to improve LKB1‐deficient tumor treatment is urgently needed. Using GEMMs for NSCLC with oncogenic Kras and LKB1 loss (KL), we found that autophagy deficiency increased the survival of the mice bearing Atg7−/− tumors compared to mice bearing wild‐type (WT) tumors. To determine the mechanism of autophagy in supporting LKB1‐deficient Kras‐driven lung tumor growth, tumor‐derived cell lines (TDCLs) were generated from the lung tumors of these mice. We found that Atg7 null TDCLs were more sensitive to glucose and glutamine deprivation‐induced cell death compared to Atg7 WT TDCLs. Atg7 null TDCLs were also more sensitive to starvation‐induced cell death than Atg7 WT TDCLs, which can be rescued by glucose, glutamine, pyruvate, lactate and nucleotide supplementation. Thus, autophagy is required for KL TDCLs to tolerate metabolic stress. Furthermore, we observed that palmitate supplementation successfully rescued starvation‐induced Atg7 null TDCLs death, indicating that autophagy is required to maintain the free fatty acid level for cells to survive starvation. We further performed metabolomics in TDCLs in normal and starvation conditions and found that level of amino acids and intermediates for glycolysis and TCA cycle metabolism were significantly lower in Atg7 null TDCLs compared to Atg7 WT TDCLs during HBSS starvation. Surprisingly, we observed a significant increase in the levels of biotin, a precursor for fatty acid synthesis, in Atg7 null TDCLs than that in WT TDCLs, indicating that accumulation of biotin in autophagy deficient cells might be due to defective fatty acid synthesis. In support of this, we found that the lipid droplets accumulation is significantly lower in Atg7 null KL TDCLs than that in Atg7 WT cells. To further evaluate the functional consequences of autophagy‐mediated lipid metabolism in supporting KL tumor growth, we treated Atg7 null and WT cells with etomoxir, an irreversible inhibitor of carnitine palmitoyltransferase‐1 (CPT‐1) to inhibit fatty acid oxidation, in normal and starvation conditions. We found that Atg7 null TDCLs are much more sensitive to etomoxir treatment than WT cells. Taken together, autophagy plays a critical role in supporting lipid metabolism for cells to survive metabolic stress. Thus, a combination of autophagy inhibition with interruption of lipid metabolism could be a novel therapeutic strategy to treat LKB1‐deficient lung tumor.Support or Funding InformationThis research has been supported by the research funds from K22 CA190521 (NIH) grant, American Cancer Society Early Investigator Pilot Award and start‐up funding from Rutgers Cancer Institute of New Jersey.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Maternal chitosan oligosaccharide supplementation during late gestation and lactation affects offspring growth

Chitosan oligosaccharide (COS), a natural compound derived from chitin, has growth promotion property. However, the nature of the relationship between maternal COS supplementation and offspring growth is not yet understood. Therefore, we intended to determine the effects of maternal COS supplementation in late gestation and lactation on the offspring growth performance. Twenty-four pregnant Yorkshire sows were distributed into two equal groups (n = 12) and fed either with a basal diet (control group) or a basal diet containing 100 mg/kg COS, from gestation day 85 until lactation day 21. Serum samples were collected from six sows of average body weight, from each group on farrowing day (lactation day 1) and lactation day 21, whereas colostrum and milk samples were respectively obtained on lactation days 1 and 21. We found that maternal COS supplementation significantly increased (p < .05) the average piglet weaning weight per litter. Supplementation of COS in the sow diet elevated (p < .05) the serum interleukin-10, immunoglobulin A (IgA) and IgM concentrations, as well as total antioxidant capacity. Moreover, higher (p < .05) colostrum IgM and milk lactose contents were simultaneously observed in COS-treated sows compared to the control sows. In summary, COS supplementation during late gestation and lactation can boost antioxidant capacity and humoural immunity of sows, and contributes to improving colostrum and milk quality, ultimately, enhancing the offspring growth performance.

A Simple Method to Reduce both Lactic Acid and Ammonium Production in Industrial Animal Cell Culture.

Fed-batch animal cell culture is the most common method for commercial production of recombinant proteins. However, higher cell densities in these platforms are still limited due to factors such as excessive ammonium production, lactic acid production, nutrient limitation, and/or hyperosmotic stress related to nutrient feeds and base additions to control pH. To partly overcome these factors, we investigated a simple method to reduce both ammonium and lactic acid production—termed Lactate Supplementation and Adaptation (LSA) technology—through the use of CHO cells adapted to a lactate-supplemented medium. Using this simple method, we achieved a reduction of nearly 100% in lactic acid production with a simultaneous 50% reduction in ammonium production in batch shaker flasks cultures. In subsequent fed-batch bioreactor cultures, lactic acid production and base addition were both reduced eight-fold. Viable cell densities of 35 million cells per mL and integral viable cell days of 273 million cell-days per mL were achieved, both among the highest currently reported for a fed-batch animal cell culture. Investigating the benefits of LSA technology in animal cell culture is worthy of further consideration and may lead to process conditions more favorable for advanced industrial applications.

Inadequate brain glycogen or sleep increases spreading depression susceptibility.

Glycogen in astrocyte processes contributes to maintenance of low extracellular glutamate and K+ concentrations around excitatory synapses. Sleep deprivation (SD), a common migraine trigger, induces transcriptional changes in astrocytes, reducing glycogen breakdown. We hypothesize that when glycogen utilization cannot match synaptic energy demand, extracellular K+ can rise to levels that activate neuronal pannexin-1 channels and downstream inflammatory pathway, which might be one of the mechanisms initiating migraine headaches. We suppressed glycogen breakdown by inhibiting glycogen phosphorylation with 1,4-dideoxy-1,4-imino-D-arabinitol (DAB) and by SD. DAB caused neuronal pannexin-1 large pore opening and activation of the downstream inflammatory pathway as shown by procaspase-1 cleavage and HMGB1 release from neurons. Six-hour SD induced pannexin-1 mRNA. DAB and SD also lowered the cortical spreading depression (CSD) induction threshold, which was reversed by glucose or lactate supplement, suggesting that glycogen-derived energy substrates are needed to prevent CSD generation. Supporting this, knocking down the neuronal lactate transporter MCT2 with an antisense oligonucleotide or inhibiting glucose transport from vessels to astrocytes with intracerebroventricularly delivered phloretin reduced the CSD threshold. In vivo recordings with a K+ -sensitive/selective fluoroprobe, Asante Potassium Green-4, revealed that DAB treatment or SD caused a significant rise in extracellular K+ during whisker stimulation, illustrating the critical role of glycogen in extracellular K+ clearance. Synaptic metabolic stress caused by insufficient glycogen-derived energy substrate supply can activate neuronal pannexin-1 channels as well as lower the CSD threshold. Therefore, conditions that limit energy supply to synapses (eg, SD) may predispose to migraine attacks, as suggested by genetic studies associating glucose or lactate transporter deficiency with migraine. Ann Neurol 2018;83:61-73.

Uticaj aplikacije niacina na lipidnu peroksidaciju kod krava u ranoj laktaciji

Niacin is a reactive part of NAD and NADP, which are co-enzymes in numerous oxidative and reductive reactions. In early lactation, there is an increased lipid mobilization, accompanied by inflammatory response and oxidative stress. The aim of this study was to examine the effect of niacin administration in cows during early lactation in reducing lipid peroxidation i.e. MDA (malondialdehyde) concentration. Niacin was administered through feed two weeks before and two weeks after calving. Blood samples were taken in the week preceding calving and in the first and second week after calving. MDA concentration was significantly lower in cows receiving niacin compared to the control group during all three samplings: 1.89±0.33:1.42±0.13 (calving, week 0); 2.37±0.41:1.64±0.15 (first week) and 2.6±0.45:1.8±0.17µmol/L (second week). In control cows, no significant correlation between MDA and NEFA concentrations was found compared to cows fed niacin. In cows receiving niacin, the concentration of MDA linearly increased, as did the NEFA concentration. Niacin supplementation in early lactation can decreaselipid peroxidation in cows. Reduced lipid peroxidation in cows can be a consequence of the antilipolytic effect of niacin.

Abstract 4399: MUC13 induced NFκB activation regulates metabolic reprograming by promoting its crosstalk with GLUT-1 receptor

Abstract Objective: Pancreatic cancer (PanCa) is the fourth most common cause of cancer-related deaths in the US. MUC13, mucin is aberrantly expressed in PanCa and promotes tumor growth and progression. Herein, we investigate the fundamental role of MUC13 in glucose metabolism and delineate the molecular interplay of various molecules governing MUC13 mediated metabolic reprograming that may be involved in pancreatic tumor maintenance. Methods: MUC13 expressing (Panc-1) and knockdown PanCa cells (HPAF-II) were generated for the study. Immunoblotting and qRT-PCR assays were performed to assess the expression of protein and mRNA levels, respectively, of key signaling molecules involved in glucose metabolism of PanCa. MUC13 and Glut-1 interaction was studied using reciprocal co-immunoprecipitation, immunofluorescence, proximity ligation, Western blotting, co-capping assays in cell lines. Lactate and glucose assays were performed using commercially available kits. In vitro functional assays using wound healing scratch assay (migration), and cell Matrigel assay (invasion) were performed in presence or absence of Lactate and 2DG supplementation. Results: Our results demonstrate that MUC13 expression leads to the TNF-induced activation/nuclear translocation of NFκB p-65 and phosphorylation of IkB which in turn upregulates additional key proteins, Glut-1, c-Myc, Bcl-2. This recruits the Glut-1 to MUC13, wherein MUC13 functionally interacts with Glut-1 and stabilizes it, initiating downstream events that result in altered glucose metabolism. MUC13 expression in PanCa cells increases glucose uptake, lactate secretion which is reduced upon MUC13 knockdown. Additionally, MUC13 mediates increased cell migratory and invasion potential which can be potentiated by supplementing the culture media with lactate, an end product of aerobic glycolysis. However, treatment of cells with NFκB inhibitor, Sulfasalazine, inhibits the MUC13 and Glut-1 interaction and abrogates all these events associated with glucose metabolism. Conclusion: These outcomes from our study suggest that MUC13 plays an important role in metabolic reprogramming of PanCa cells metabolism to induce cancer growth and enhanced cellular invasion and motility. NFκB acts downstream of MUC13 to coordinate the events leading to its interation with Glut-1 and metabolic reprogramming. Overall, these findings illustrate mechanisms by which MUC13 coordinates the shift in metabolism to sustain cancer growth and invasion in PanCa. Citation Format: Sonam Kumari, Sheema Khan, Subash C. Gupta, Vivek K. Kashyap, Murali M. Yallapu, Subhash C. Chauhan, Meena Jaggi. MUC13 induced NFκB activation regulates metabolic reprograming by promoting its crosstalk with GLUT-1 receptor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4399. doi:10.1158/1538-7445.AM2017-4399

Lactate supplementation in severe traumatic brain injured adults by primed constant infusion of sodium L-lactate.

Carbohydrate fuel augmentation following traumatic brain injury may be a viable treatment to improve recovery when cerebral oxidative metabolism of glucose is depressed. We performed a primed constant sodium L-lactate infusion in 11 moderate to severely brain injured adults. Blood was collected before and periodically during the infusion study. We quantified global cerebral uptake of glucose and lactate and other systemic metabolites associated with energy metabolism. Our hypothesis was that cerebral lactate uptake, as measured by the arteriovenous difference of lactate (AVDlac), would increase in severely injured TBI patients in the neurocritical care unit. Infusion of sodium L-lactate changed net cerebral lactate release, where the arteriovenous difference of lactate is negative, to net cerebral lactate uptake. Results from a mixed effects model of AVDlac with the fixed effects of infusion time, arterial lactate concentration, arterial glucose concentration and arteriovenous difference of glucose shows that doubling arterial lactate concentration (from .92 to 1.84 mM) results in an increase in AVDlac from -.078 mM to .090 mM. We did not detect changes in systemic glucose during the course of the infusion study and observed significant changes in alanine (30% [20 39]), glutamine (34% [24 43]), acetate (87% [60 113]), valine (40% [28 51]), and leucine (24% [16 32]) from baseline levels. Further studies are required to establish the impact of lactate supplementation on cerebral and systemic flux of lactate, on gluconeogenesis, and on the impact on cerebral energetics following injury. © 2017 Wiley Periodicals, Inc.

Effects of dietary organic acid supplementation on the growth, nutrient digestibility and intestinal histology of the giant grouper Epinephelus lanceolatus fed a diet with soybean meal

The purpose of this study was to evaluate the effects of dietary organic acid (butyrate and lactate) supplementation on the growth, nutrient digestibility and intestinal histology of the giant grouper Epinephelus lanceolatus that was fed a diet containing soybean meal. The diet that included soybean meal, which replaced 40% fish meal protein, was used as the control. One percent butyrate and lactate were added to the control diet to form the two experimental diets. Also, the all fish meal diet without organic acid was also included for comparison. A total of four experimental diets were each fed to three groups of giant grouper (initial wt: 17.37±0.18g) in a recirculating rearing system for 8weeks. After the growth trial, the nutrient digestibility by the fish was determined by using 0.5% chromic oxide as an inert indicator. The fish fed the all fish meal diet gained more (P<0.05) weight than fish fed the control and the 1% lactate diets. The hepatic thiobarbituric acid reactive substance (TBARS) value was higher in the fish fed the control diet than that in other dietary treatments. Dry matter, lipid, copper (Cu), zinc (Zn), calcium (Ca) and phosphorus (P) digestibility were higher in fish fed the all fish meal diet, the 1% butyrate and lactate supplemented diets than the fish fed the control diet. The fish fed the control diet showed disordered lamina epithelialis and extended lamina propria comparing to the fish fed the all fish meal diet and 1% butyrate-diet. The results indicated that growth, nutrient digestibility and intestinal histology were adversely affected by replacement of the fish meal by soybean meal in giant grouper. The diet supplemented with 1% butyrate improved the negative effects excluding growth for the fish. Statement of relevanceTo evaluate feed additives on growth, nutrient digestibility and intestinal histology of giant grouper fed diets with soybean meal.

Chronic lactate supplementation does not improve blood buffering capacity and repeated high-intensity exercise.

Since there is conflicting data on the buffering and ergogenic properties of calcium lactate (CL), we investigated the effect of chronic CL supplementation on blood pH, bicarbonate, and high-intensity intermittent exercise performance. Sodium bicarbonate (SB) was used as a positive control. Eighteen athletes participated in this double-blind, placebo-controlled, crossover, fully counterbalanced study. All participants underwent three different treatments: placebo (PL), CL, and SB. The dose was identical in all conditions: 500mg/kg BM divided into four daily individual doses of 125mg/kg BM, for five consecutive days, followed by a 2-7-day washout period. On the fifth day of supplementation, individuals undertook four 30-s Wingate bouts for upper body with 3-min recovery between bouts. Total mechanical work (TMW) for the overall protocol and for the initial (1st+2nd) and final (3rd+4th) bouts was determined at each session. Blood pH, bicarbonate, and lactate levels were determined at rest, immediately and 5min after exercise. CL supplementation did not affect performance (P>0.05 for the overall TMW as well for initial and final bouts), nor did it affect blood bicarbonate and pH prior to exercise. SB supplementation improved performance by 2.9% for overall TMW (P=0.02) and 5.9% in the 3rd+4th bouts (P=0001). Compared to the control session, SB also promoted higher increases in blood bicarbonate than CL and PL (+0.03±0.04 vs +0.009±0.02 and +0.01±0.03, respectively). CL supplementation was not capable of enhancing high-intensity intermittent performance or changing extracellular buffering capacity challenging the notion that this dietary supplement is an effective buffering agent.