Untitled

Lai, James C. K.; Behar, Kevin L.; Bing, Liang; Hertz, Leif

doi:10.1023/a:1020761831295

Cited by 18 publications

(5 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…From the astrocyte-to-neuron lactate shuttle hypothesis it follows that the level of glycolysis is required to be higher in astrocytes than neurons and thus hexokinases should be expressed preferentially in astrocytes. Gene expression analysis of FACS sorted pools of cortical neurons and astrocytes showed that both cell types express HK enzymes, as expected ( 33 , 35 , 36 ). However, the qPCR data of the mRNA revealed that the HK1, HK2, and HK3 genes were consistently expressed at a higher level in neurons than in astrocytes ( Fig.…”

Section: Resultssupporting

confidence: 78%

See 1 more Smart Citation

Direct neuronal glucose uptake heralds activity-dependent increases in cerebral metabolism

et al. 2015

View full text Add to dashboard Cite

Metabolically, the brain is a highly active organ that relies almost exclusively on glucose as its energy source. According to the astrocyte-to-neuron lactate shuttle hypothesis, glucose is taken up by astrocytes and converted to lactate, which is then oxidized by neurons. Here we show, using 2-photon imaging of a near-infrared 2-deoxyglucose analogue (2DG-IR), that glucose is taken up preferentially by neurons in awake behaving mice. Anesthesia suppressed neuronal 2DG-IR uptake and sensory stimulation was associated with a sharp increase in neuronal, but not astrocytic, 2DG-IR uptake. Moreover, hexokinase, which catalyze the first enzymatic steps in glycolysis, was highly enriched in neurons compared with astrocytes, in mouse as well as in human cortex. These observations suggest that brain activity and neuronal glucose metabolism are directly linked, and identifies the neuron as the principal locus of glucose uptake as visualized by functional brain imaging.

show abstract

Section: Resultssupporting

confidence: 78%

“…Hexokinases are housekeeping enzymes that catalyze the first step of glycolysis ( 35 , 36 ). Analysis of gene expression in FACS sorted neuron and astrocytes showed that all 3 isoforms of hexokinase (HK1-3) are expressed at higher levels in neurons than astrocytes.…”

Section: Discussionmentioning

confidence: 99%

Direct neuronal glucose uptake heralds activity-dependent increases in cerebral metabolism

et al. 2015

View full text Add to dashboard Cite

show abstract

“…3). Furthermore, evidence suggests that hexokinase activity is not significantly different between neurons and glia [65, 66], and that the enzyme has a slower rate (rate-limiting step) compared to uptake and extrusion in neurons [63]. Another potential interpretation is that glial cells do not use 2-NBDG and that upon entering the cell, the glucose analog is readily transported out prior to being phosphorylated by hexokinase.…”

Section: Discussionmentioning

confidence: 99%

Imaging of a glucose analog, calcium and NADH in neurons and astrocytes: Dynamic responses to depolarization and sensitivity to pioglitazone

et al. 2011

View full text Add to dashboard Cite

Neuronal Ca2+ dyshomeostasis associated with cognitive impairment and mediated by changes in several Ca2+ sources has been seen in animal models of both aging and diabetes. In the periphery, dysregulation of intracellular Ca2+ signals may contribute to the development of insulin resistance. In the brain, while it is well-established that type 2 diabetes mellitus is a risk factor for the development of dementia in the elderly, it is not clear whether Ca2+ dysregulation might also affect insulin sensitivity and glucose utilization. Here we present a combination of imaging techniques testing the disappearance of the fluorescent glucose analog 2-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose (2-NBDG) as an indication of glycolytic activity in neurons and astrocytes. Our work shows that glucose utilization at rest is greater in neurons compared to astrocytes, and ceases upon activation in neurons with little change in astrocytes. Pretreatment of hippocampal cultures with pioglitazone, a drug used in the treatment of type 2 diabetes, significantly reduced glycolytic activity in neurons and enhanced it in astrocytes. This series of experiments, including FURA-2 and NADH imaging, provides results that are consistent with the idea that Ca2+ levels may rapidly alter glycolytic activity, and that downstream events beyond Ca2+ dysregulation with aging, may alter cellular metabolism in the brain.

show abstract

“…OeHK , the first rate-limiting enzyme in the glycolytic pathway, was found to be down-regulated in CG. These findings may have implications for assessing glycolytic flux and its regulation in olive oil metabolism ( Lai et al, 1999 ).…”

Section: Discussionmentioning

confidence: 99%

Integrated lipidomic and transcriptomic analysis reveals diacylglycerol accumulation in olive of Longnan (China)

Hu,

Ma,

Zhang

et al. 2023

PeerJ

View full text Add to dashboard Cite

Background Olive (Olea europaea L.) oil accumulate more diacylglycerols (DAG) than mostly vegetable oils. Unsaturated fatty acids-enriched DAG consumption enhanced wellness in subjects. However, the mechanism of DAG accumulation is not yet fully understood. Methods In this study, gene network of DAG accumulation and fatty acid composition in the two olive mesocarps (“Chenggu 32” (CG) and “Koroneiki” (QJ)) were investigated by integrating lipidome and transcriptome techniques. Results A total of 1,408 lipid molecules were identified by lipidomic analysis in olive mesocarp, of which DAG (DAG36:3, DAG36:4 and DAG36:5) showed higher content, and triacylglycerols (TAG54:3, TAG54:4) exhibited opposite trend in CG. Specifically, DAG was rich in polyunsaturated fatty acids (especially C18:2) at the sn-2 position, which was inconsistent with TAG at the same positions (Primarily C18:1). Transcriptomic analysis revealed that phospholipase C (NPC, EC 3.1.4.3) were up-regulated relative to QJ, whereas diacylglycerol kinase (ATP) (DGK, EC 2.7.1.107), diacylglycerol acyltransferase (DGAT, EC 2.3.1.20), and phospholipid: diacylglycerol acyltransferase (PDAT, EC 2.3.1.158) were down-regulated. Conclusion We speculated that the non-acyl coenzyme A pathway played a significant role in DAG biosynthesis. Additionally, fatty acyl-ACP thioesterase B (FATB, EC 3.1.2.14), stearoyl [acyl-carrier-protein] 9-desaturase (SAD, EC 1.14.19.2) and omega-6 fatty acid desaturase (FAD2, EC 1.14.19.6) were highly expressed in CG and may be involved in regulating fatty acid composition. Meanwhile, phospholipase A1 (LCAT, EC 3.1.1.32) involved in the acyl editing reaction facilitated PUFA linkage at the sn-2 position of DAG. Our findings provide novel insights to increase the DAG content, improve the fatty acid composition of olive oil, and identify candidate genes for the production of DAG-rich oils.

show abstract

Untitled

Cited by 18 publications

References 27 publications

Direct neuronal glucose uptake heralds activity-dependent increases in cerebral metabolism

Direct neuronal glucose uptake heralds activity-dependent increases in cerebral metabolism

Imaging of a glucose analog, calcium and NADH in neurons and astrocytes: Dynamic responses to depolarization and sensitivity to pioglitazone

Integrated lipidomic and transcriptomic analysis reveals diacylglycerol accumulation in olive of Longnan (China)

Contact Info

Product

Resources

About