High impact information on MGPD

• In the discussion, we raise the possible roles of G3PD and of ATP in protein synthesis at the PSD, the regulation by NO, as well as the overall regulatory role of the PSD complex in synaptic transmission [1].
• The activation of pure glycerol-3-phosphate dehydrogenase by either L-ascorbic acid or iron or its combination could be totally inhibited by 200 microm propyl gallate [2].
• Polyhydroxybenzoates inhibit ascorbic acid activation of mitochondrial glycerol-3-phosphate dehydrogenase: implications for glucose metabolism and insulin secretion [2].
• Glycerol-3-phosphate dehydrogenase from pig brain mitochondria was stimulated 2.2-fold by the addition of 50 microm l-ascorbic acid [2].
• Homogeneous pig brain mitochondrial glycerol-3-phosphate dehydrogenase was activated by either 150 microm L-ascorbic acid (56%) or 300 microm iron (Fe(2+) or Fe(3+) (62%)) and 2.6-fold by the addition of both L-ascorbic acid and iron [2].

Biological context of MGPD

• 5. G3PD and PGK catalytic activity in synaptosomes suggests a role in glycolysis, as well as actin binding, in the presynaptic terminals [3].
• Insulin alone and hydrocortisone alone stimulated a low level of cell differentiation, as indicated by an increase in glycerol-3-phosphate dehydrogenase activity [4].

Anatomical context of MGPD

• 3. Highest levels of G3PD catalytic activity were found in synaptosomes and PSDs [3].
• Glycerol 3-phosphate dehydrogenase of boar spermatozoa: inhibition by alpha-bromohydrin phosphate [5].
• Further analysis of subcellular fractions from synaptosomes showed the PSD but not the synaptosomal plasma membranes to be enriched in G3PD and actin [3].
• On the other hand, the high levels of G3PD activity in PSDs but lack of PGK activity suggests that G3PD is involved in nonglycolytic functions, such as actin binding and actin filament network organization [3].
• Overall, stromal-vascular cultures from hypophysectomized fetuses contained fewer fat cell clusters and concomitantly lower glycerol-3-phosphate dehydrogenase specific enzyme activity than did cultures from littermate controls [6].

Associations of MGPD with chemical compounds

• At the end of this treatment period, cultures were either prepared for lipid staining using Oil Red O or for marker enzyme analysis (glycerol-3-phosphate dehydrogenase activity; GPDH) [7].
• The results reported here confirm that in boar spermatozoa glycerol 3-phosphate dehydrogenase is an FAD-linked enzyme that is inhibited by (R,S)-alpha-bromohydrin phosphate in, possibly, a competitive manner [5].
• At lower concentrations (0.1 to 10 nM), retinoic acid had no effect on the GPDH activity [8].
• The NBPC had higher (P < .05) sn-glycerol-3-phosphate dehydrogenase (GPDH; EC 1.1.1.8) per protein than MPC regardless of the medium [9].
• In the presence of insulin, stimulation by T3 or hydrocortisone alone had no effect on glycerol 3-phosphate dehydrogenase activity, whereas their concomitant addition significantly increased it [10].

Other interactions of MGPD

• However, when compared with continuous culture in serum-containing medium, the serum-free conditions were significantly more adipogenic as assessed by increased lipid content and increased enzymatic activities for lipoprotein lipase, glycerol 3-phosphate dehydrogenase, and malic enzyme [10].

Analytical, diagnostic and therapeutic context of MGPD

• The ATP was shown to be used by the PSD Ca2+/calmodulin-dependent protein kinase and can probably be used by two other PSD kinases, protein kinase A and protein kinase C. We confirmed by immunocytochemistry the presence of G3PD in the PSD and its binding to actin [1].
• 2. We have shown G3PD association with 0.5-microgram synaptosomal particles by immunofluorescence as similarly demonstrated for actin (Toh et al., Nature 264:648-650, 1976) [3].

References