BACKGROUND Fasting is a rigorous type of dietary restriction that is associate with a number of health benefits. During fasting, ketone bodies significantly increase in blood and become major body fuels, thereby sparing glucose. In the present study, we investigated effects of fasting on hypersensitivity. In addition, we also investigated the possible role of D-beta-hydroxybutyrate provoked by ...

Mitochondrial anaplerosis is important for insulin secretion, but only some of the products of anaplerosis are known. We discovered novel effects of mitochondrial metabolites on insulin release in INS-1 832/13 cells that suggested pathways to some of these products. Acetoacetate, beta-hydroxybutyrate, alpha-ketoisocaproate (KIC), and monomethyl succinate (MMS) alone did not stimulate insulin re...

β-Hydroxybutyrate, a ketone body that is used as an energy source in organs such as the brain, muscle, and heart when blood glucose is low, is produced by fatty acid oxidation in the liver under the fasting state. Endoplasmic reticulum (ER) stress is linked with the generation of intracellular reactive oxygen species and the accumulation of misfolded protein in the ER. ER stress is known to ind...

Adipocytes are the most abundant stromal partners in breast tissue. However, the crosstalk between breast cancer cells and adipocytes has been given less attention compared to cancer-associated fibroblasts. Here we find, through systematic screening, that primary mammary gland-derived adipocytes (MGDAs) promote growth of breast cancer cells that express monocarboxylate transporter 2 (MCT2) both...

To provide 4-hydroxybutyryl-CoA for poly(3-hydroxybutyrate-co-4-hydroxybutyrate) formation from glutamate in Escherichia coli, an acetyl-CoA:4-hydroxybutyrate CoA transferase from Clostridium kluyveri, a 4-hydroxybutyrate dehydrogenase from Ralstonia eutropha, a gamma-aminobutyrate:2-ketoglutarate transaminase from Escherichia coli, and glutamate decarboxylases from Arabidopsis thaliana or E. c...

Recent studies have highlighted the therapeutic and ergogenic potential of ketone body ester, (R)-3-hydroxybutyl-(R)-3-hydroxybutyrate. In present work, enzymatic synthesis this biological active compound is reported. The (R)-3-hydroxybutyl-(R)-3-hydroxybutyrate has been produced through transesterification racemic ethyl 3-hydroxybutyrate with (R)-1,3-butanediol by exploiting selectivity Candid...

The enzymic determination of D-3-hydroxybutyrate and acetoacetate normally involves the use of 3hydroxybutyrate dehydrogenase (HBDH, EC 1.1.1.30) of bacterial origin. We show that HBDH from Rhodopseudomonas spheroides (BCL, grade II) contains a 3-hydroxyisobutyrate dehydrogenase (HIBDH) activity: activity with 3-hydroxyisobutyrate as substrate was > 10% of that with 3-hydroxybutyrate. However, ...

We have identified two Sinorhizobium meliloti chromosomal loci affecting the poly-3-hydroxybutyrate degradation pathway. One locus was identified as the gene acsA, encoding acetoacetyl coenzyme A (acetoacetyl-CoA) synthetase. Analysis of the acsA nucleotide sequence revealed that this gene encodes a putative protein with a molecular weight of 72,000 that shows similarity to acetyl-CoA synthetas...

The activities of several enzymes of the citric acid and poly-beta-hydroxybutyrate cycles were measured in Rhizobium japonicum 3I1B-143 bacteroids which had been isolated from soybean nodules by sucrose gradient centrifugation. During the period of developing nitrogenase activity, the specific activity of fumarase, hydroxybutyrate dehydrogenase, beta-ketothiolase, and pyruvate dehydrogenase com...

The effects of gamma hydroxybutyrate, a coma inducing recreational drug, are described and illustrated by case reports of five patients presenting to accident and emergency (A&E). All had depressed levels of consciousness. There was strong circumstantial evidence of gamma hydroxybutyrate ingestion in all cases, and laboratory evidence in two. All recovered and supportive treatment. gamma Hydrox...