Pathways

Pyruvate is an intermediate compound in the metabolism of fats, proteins, and carbohydrates. It can be formed from glucose via glycolysis or the transamination of alanine. It can be converted into Acetyl-CoA to be used as the primary energy source for the TCA cycle, or converted into oxaloacetate to replenish TCA cycle intermediates. Pyruvate can also be used to synthesize carbohydrates, fatty acids, ketone bodies, alanine, and steroids. In conditions of inssuficient oxygen or in cells with few mitochondria, pyruvate is reduced to lactate in order to re-oxidize NADH back into NAD+ Pyruvate participates in several key reactions and pathways. In glycolysis, phosphoenolpyruvate (PEP) is converted to pyruvate by pyruvate kinase in an highly exergonic and irreversible reaction. In gluconeogenesis, pyruvate carboxylase and PEP carboxykinase are needed to catalyze the conversion of pyruvate to PEP. In fatty acid synthesis, the pyruvate dehydrogenase complex decarboxylates pyruvate to produce acetyl-CoA. In gluconeogenesis, the carboxylation by pyruvate carboxylase produces oxaloacetate. The fate of pyruvate depends on the cell energy charge. In cells or tissues with a high energy charge pyruvate is directed toward gluconeogenesis, but when the energy charge is low pyruvate is preferentially oxidized to CO2 and H2O in the TCA cycle, with generation of 15 equivalents of ATP per pyruvate. The enzymatic activities of the TCA cycle are located in the mitochondrion. When transported into the mitochondrion, pyruvate encounters two principal metabolizing enzymes: pyruvate carboxylase (a gluconeogenic enzyme) and pyruvate dehydrogenase (PDH). With a high cell-energy charge, acetyl-CoA, is able allosterically to activate pyruvate carboxylase, directing pyruvate toward gluconeogenesis. When the energy charge is low CoA is not acylated, pyruvate carboxylase is inactive, and pyruvate is preferentially metabolized via the PDH complex and the enzymes of the TCA cycle to CO2 and H2O.

The reaction of pyruvate to cytochrome bd terminal oxidase electron transfer starts with 2 pyruvate and 2 water molecules reacting in a pyruvate oxidase resulting in the release of 4 electrons into the inner membrane, and releasing 2 carbon dioxide molecules , 2 acetate and 4 hydrogen ion into the cytosol. 2 ubiquinone,4 hydrogen ion and 4 electron ion react resulting in the release of 2 ubiquinol . The 2 ubiquinol in turn release 4 hydrogen ions into the periplasmic space through a cytochrome bd-I terminal oxidase and releasing 4 electrons through the enzyme. Oxygen and 4 hydrogen ion reacts with the 4 electrons resulting in 2 water molecules.

The reaction of pyruvate to cytochrome bd terminal oxidase electron transfer starts with 2 pyruvate and 2 water molecules reacting in a pyruvate oxidase resulting in the release of 4 electrons into the inner membrane, and releasing 2 carbon dioxide molecules , 2 acetate and 4 hydrogen ion into the cytosol. 2 ubiquinone,4 hydrogen ion and 4 electron ion react resulting in the release of 2 ubiquinol . The 2 ubiquinol in turn release 4 hydrogen ions into the periplasmic space through a cytochrome bd-I terminal oxidase and releasing 4 electrons through the enzyme. Oxygen and 4 hydrogen ion reacts with the 4 electrons resulting in 2 water molecules.

Pyrvinium is a drug that is not metabolized by the human body as determined by current research and biotransformer analysis. Pyrvinium passes through the liver and is then excreted from the body mainly through the kidney.

Quaternium-15 is a drug that is not metabolized by the human body as determined by current research and biotransformer analysis. Quaternium-15 passes through the liver and is then excreted from the body mainly through the kidney.

Quazepam is a long-acting benzodiazepine used to manage insomnia. It appears to be unique amongst other benzodiazepine derivatives in its relatively high affinity for sleep-promoting α1 subunit-containing GABAA receptors and low affinity for other receptors. It can be found under the brand name Doral. Quazepam is indicated for the treatment of insomnia characterized by difficulty falling asleep, frequent nocturnal awakenings, and/or early morning awakenings. Like other benzodiazepines, quazepam likely exerts its effects by potentiating the effect of gamma-aminobutyric acid (GABA) on GABA(A) receptors, the main inhibitory neurotransmitter receptors in the mammalian brain. GABA(A) receptors are a component of GABA-gated ionotropic chloride channels that produce inhibitory postsynaptic potentials - following activation by GABA, the channel undergoes a conformational change that allows the passage of chloride ions through the channel. The inhibitory potentials produced by GABA neurotransmission play an integral role in the suppression and control of epileptiform nerve firing such as that seen in epilepsy, which makes the GABA system a desirable target in the treatment of epilepsy. Benzodiazepines are positive allosteric modulators of GABA(A) function. They bind to the interface between alpha (α) and gamma (γ) subunits on the receptor, commonly referred to as the benzodiazepine binding site, and modulate the receptor such that its inhibitory response to GABA binding is dramatically increased. Quazepam is administered as an oral tablet. Possible side effects of using quazepam may include drowsiness, lowered alertness, confusion, and loss of coordination.