Glutamine plays a central role in the metabolism of critical biological molecules such as amino acids, proteins, neurotransmitters, and glutathione. Since glutamine metabolism is regulated through multiple enzymes and transporters, the cellular glutamine concentration is expected to be temporally dynamic. Moreover, differentiation in glutamine metabolism between cell types in the same tissue (e...

Glutamine has many important functions in mammalian cells, and glutamine transport across cell membranes has accordingly been extensively studied. In the past few years a number of important glutamine transport proteins have been sequenced and their molecular properties have been characterised. In general, four major transporters are important physiologically. These are known as (i) SNAT3 (Syst...

This study characterized the Na+-dependent transport of L-glutamine by a human neuroblastoma cell line, SK-N-SH. The Na+-dependent component represented >95% of the total glutamine uptake. Kinetic studies showed a single saturable high-affinity carrier with a Michaelis constant (K(m)) of 163 +/- 23 microM and a maximum transport velocity (Vmax) of 13,713 +/- 803 pmol x mg protein(-1) x min(-1)....

Glutamine is a nonessential amino acid contained in most dietary proteins and provides immune functions and fuel for the small intestine. For healthy people, dietary glutamine (from protein) usually is considered adequate. Results of research evaluating the potential benefits of glutamine during cancer therapy are encouraging but remain inconclusive. Some researchers have suggested recently tha...

Driven by oncogenic signaling, glutamine addiction exhibited by cancer cells often leads to severe glutamine depletion in solid tumors. Despite this nutritional environment that tumor cells often experience, the effect of glutamine deficiency on cellular responses to DNA damage and chemotherapeutic treatment remains unclear. Here, we show that glutamine deficiency, through the reduction of alph...

Urinary stone disease (USD) is a polyetiological urological caused by both exogenous and endogenous factors, including hereditary ones. It characterized the appearance of stones in kidneys urinary tract, tendency to relapse, often with severe course. Almost 25 % consist uric acid (UA). The leading role pathogenesis urate nephrolithiasis (UN) played disorders purine metabolism, which are develop...

Glutamate is the principal excitatory neurotransmitter in brain. Although it is rapidly synthesized from glucose in neural tissues the biochemical processes for replenishing the neurotransmitter glutamate after glutamate release involve the glutamate-glutamine cycle. Numerous in vivo(13)C magnetic resonance spectroscopy (MRS) experiments since 1994 by different laboratories have consistently co...

The system N transporter SN1 has been proposed to mediate the efflux of glutamine from cells required to sustain the urea cycle and the glutamine-glutamate cycle that regenerates glutamate and gamma-aminobutyric acid (GABA) for synaptic release. We now show that SN1 also mediates an ionic conductance activated by glutamine, and this conductance is selective for H(+). Although SN1 couples amino ...

BACKGROUND Enteral feeding of very low birth weight (VLBW) infants is a challenge, since metabolic demands are high and administration of enteral nutrition is limited by immaturity of the gastrointestinal tract. The amino acid glutamine plays an important role in maintaining functional integrity of the gut. In addition, glutamine is utilised at a high rate by cells of the immune system. In crit...