PURPOSE: We evaluated new (111)In-labeled amino acid derivatives, in which the amino acids are conjugated with1,4,7,10-tetra-azacyclododecane-1,4,7,10-tetraacetic acid (DOTA), 1,4,7,10-tetraazacyclododecane-1,7-diacetic acid (DO2A) or 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A). METHODS: DOTA-aminoalanine (DOTA-A), DOTA-aminohomoalanine (DOTA-H), DOTA-lysine (DOTA-L), DO2A-alanine (DO2A-A), DO3A-alanine (DO3A-A) and DO3A-homoalanine (DO3A-H) were labeled with (111)In. In vitro cell uptake assays were performed ...

Here we present the first application of pore-expanded SBA-15 in heterogeneous catalysis. Pore expansion over the range 6-14 nm confers a striking activity enhancement towards fatty acid methyl ester (FAME) synthesis from triglycerides (TAG), and free fatty acid (FFA), attributed to improved mass transport and acid site accessibility.

ABCG2 is involved in epithelial transport/barrier functions. Here we have investigated its ability to transport bile acids in liver and placenta. Cholylglycylamido fluorescein (CGamF) was exported by WIF-B9/R cells, which do not express BSEP. Sensitivity to typical inhibitors suggested that CGamF export was mainly mediated by ABCG2. In CHO cells, ...

Using a transgenic mouse (Mus musculus) in which nestin-expressing progenitors are labeled with enhanced green fluorescent protein, we previously characterized the expression of excitatory amino acid transporter 2 (GltI) and excitatory amino acid transporter 1 (Glast) on early neural progenitors in vivo. To address their functional role in this cell ...

Kynurenic acid, a catabolite of tryptophan, is suggested to be involved in schizophrenia, and is known to be a uremic toxin, although there is little information about the mechanism of its disposition. In this study, we performed uptake experiment using Xenopus laevis oocyte expression system to examine the transport of ...

Objective. The vocal fold epithelium is routinely exposed to gastric contents, including acid and pepsin, during laryngopharyngeal reflux events. The epithelium may possess intrinsic defenses to reflux. The first objective of the current study was to examine whether vocal fold epithelial ion transport is one potential mechanism of defense to ...

Fumaric acid esters are used to treat psoriasis, an inflammatory skin disease characterized by keratinocyte proliferation. Inflammation and proliferation are hallmarks of retinal disease; hence, fumaric acid esters may have therapeutic value in retinal pathology. In diseased retinas, Müller glial cells (MCs) undergo reactive gliosis, a hyperproliferative state. MCs take ...

The mTOR complex 1 (mTORC1) protein kinase is a master growth regulator that is stimulated by amino acids. Amino acids activate the Rag guanosine triphosphatases (GTPases), which promote the translocation of mTORC1 to the lysosomal surface, the site of mTORC1 activation. We found that the vacuolar H(+)-adenosine triphosphatase ATPase (v-ATPase) ...

A nonarteriosclerotic cardiomyopathy is increasingly seen in obese patients. Seeking a rodent model, we studied cardiac histology, function, cardiomyocyte fatty acid uptake, and transporter gene expression in male C57BL/6J control mice and three obesity groups: similar mice fed a high-fat diet (HFD) and db/db and ob/ob mice. At sacrifice, all ...

The neurodegenerative disease X-linked adrenoleukodystrophy (X-ALD) is characterized by the abnormal accumulation of very long chain fatty acids. Mutations in the gene encoding the peroxisomal ATP-binding cassette half-transporter, adrenoleukodystrophy protein (ALDP), are the primary cause of X-ALD. To gain a better understanding of ALDP dysfunction, we searched for interaction partners ...

The production, use, and disposal of nanomaterials may inevitably lead to their appearance in water. With the development of new industries around nanomaterials, it seems necessary to be concerned about the transport of nanomaterials in the environment. In this paper, the transport of acid-treated carbon nanotubes (CNTs) in porous media ...

Authors' response: on sialic acid transport and utilization by Vibrio cholerae.

Arabidopsis ATP-binding cassette B4 (ABCB4) is a root-localised auxin efflux transporter with reported auxin uptake activity in low auxin concentrations. Results reported here demonstrate that ABCB4 is a substrate-activated regulator of cellular auxin levels. The contribution of ABCB4 to shootward auxin movement at the root apex increases with auxin concentration, ...

Glycerophosphodiesters are the products of phospholipase-mediated deacylation of phospholipids. In Saccharomyces cerevisiae, a single gene, GIT1, encodes a permease responsible for importing glycerophosphodiesters, such as glycerophosphoinositol and glycerophosphocholine, into the cell. In contrast, the Candida albicans genome contains four open reading frames (ORFs) with a high degree of similarity to ...

Our knowledge of how the body absorbs triacylglycerols (TAG) from the diet and how this process is regulated has increased at a rapid rate in recent years. Dietary TAG are hydrolyzed in the intestinal lumen to free fatty acids (FFA) and monoacylglycerols (MAG), which are taken up by enterocytes from ...

Theories regarding the mechanism of intravenous fat emulsion for bupivacaine cardiotoxicity include creation of an intravascular lipid sink into which the cardiotoxic drug is sequestered, an improvement of impaired cardiac metabolism, and restoration of cardiomyocyte function by increasing intracellular calcium. However, work in this area is inconclusive and a more ...

Long-chain fatty acids (LCFA) serve as structural components for membrane biogenesis and as primary energy sources during mitochondrial β-oxidation reactions. Hepatic LCFA uptake is complex, with characteristics suggestive of a dual-kinetic model manifested by rapid (carrier-assisted/facilitated) and delayed (passive diffusional) phases. Our previous work using mice deficient of the Iqgap2 ...

Present study highlights the importance of RF sputtered NiO thin film deposited on platinum coated glass substrate (NiO/Pt/Ti/glass) as a potential matrix for the realization of highly sensitive and selective uric acid biosensor. Uricase has been immobilized successfully onto the surface of NiO matrix by physical adsorption technique. The prepared ...

INTRODUCTION: We investigated the mechanisms of trans-1-amino-3-fluoro[1-(14)C]cyclobutanecarboxylic acid (anti-[(14)C]FACBC) transport by human-derived prostate cancer (PCa) cells and normal human prostatic epithelial cells (PrECs). METHODS: Using PCa cells (DU145, PC-3, LNCaP) and PrECs, we performed the following in vitro experiments: time-course, kinetics, competitive inhibition by synthetic/naturally occurring amino acids (AAs), exchange ...

Cardiolipin (CL) is a unique phospholipid (PL) found in the mitochondria of mammalian cells. CL remodeling is accompanied by turnover of its fatty acid acyl groups. Abnormalities in CL remodeling have been found in Barth's syndrome, diabetes, and obesity. The objective of this study was to determine nonessential fatty acid ...

Uptake of long-chain fatty acids plays pivotal roles in metabolic homeostasis and human physiology. Uptake rates must be controlled in an organ-specific fashion to balance storage with metabolic needs during transitions between fasted and fed states. Many obesity-associated diseases, such as insulin resistance in skeletal muscle, cardiac lipotoxicity, and hepatic ...

An experiment was conducted with piglets to determine the effect of dietary phytic acid supplementation on performance, electrophysiological properties of jejunum mounted in Ussing chambers, sodium-dependent glucose transporter 1 (SGLT1) protein expression in jejunum, and plasma glucose and Na levels. Sixteen piglets with an average initial BW of 7.40 ± ...

Campylobacter jejuni is a leading cause of diarrheal disease in humans and an intestinal commensal in poultry and other agriculturally important animals. These zoonotic infections result in significant amounts of C. jejuni present in the food supply to contribute to disease in humans. We previously found that a transposon insertion ...

Aquaporins are integral membrane proteins that facilitate the transport of water and some small solutes across cellular membranes. X-ray crystallography of aquaporins indicates that four amino acids constitute an aromatic/arginine (ar/R) pore constriction known as the selectivity filter. On the basis of these four amino acids, tonoplast aquaporins called tonoplast ...

H(+),K(+)-ATPase is a key enzyme in the process of gastric acid secretion, and proton pump inhibitors (PPIs) have been accepted as one of the most effective treatments for peptic ulcer and gastroesophageal reflux disease. To discover a novel class of PPIs, the authors screened a low-molecular-weight compound library and identified ...

Gastric absorption of feruloylquinic acid and di-O-caffeoylquinic acid analogs has never been investigated despite their potential contribution to the proposed beneficial health effects leading to reduced risk of type 2 diabetes. Using a cultured gastric epithelial model, with an acidic apical pH, the relative permeability coefficients (P(app)) and metabolic fate ...

JAK2 (Janus kinase-2) is expressed in a wide variety of cells including tumor cells and contributes to the proliferation and survival of those cells. The gain of function mutation (V617F)JAK2 mutant is found in the majority of myeloproliferative diseases. Cell proliferation depends on the availability of amino acids. Concentrative cellular ...

It has been reported that polymorphisms in the organic anion transporting polypeptide 1B1 (OATP1B1 and SLCO1B1) result in decreased hepatic uptake of simvastatin carboxy acid, the active metabolite of simvastatin. This is not the case for fluvastatin and it has been hypothesized that for this drug other hepatic uptake pathways ...

Intracellular pH conditions many cellular systems but its mechanisms of regulation and perception are mostly unknown. We have identified two yeast genes important for tolerance to intracellular acidification caused by weak permeable acids. One corresponded to LEU2 and functions by removing the dependency of the leu2 mutant host strain on ...

The ATP-binding cassette (ABC) transporter protein MRP1 (ABCC1) plays an important role in the cellular efflux of the high priority environmental carcinogen arsenic, as a triglutathione conjugate [As(GS)(3)]. Most mammalian cells can methylate arsenic to monomethylarsonous acid (MMA(III)), monomethylarsonic acid (MMA(V)), dimethylarsinous acid (DMA(III)) and dimethylarsinic acid (DMA(V)). The trivalent ...

The reactive uptake of NO(3) by particles containing four unsaturated fatty acid species was studied for the first time in a flow tube reactor coupled to a chemical ionization mass spectrometer (CIMS). Using a mixed-phase relative rates technique, the reactive uptake coefficients, γ(part), were determined to be (0.27 ± 0.06) ...

The existence of a transport protein that imports cytosolic NAD(+) into peroxisomes has been controversially discussed for decades. Nevertheless, the biosynthesis of NAD(+) in the cytosol necessitates the import of NAD(+) into peroxisomes for numerous reduction/oxidation (redox) reactions. However, a gene encoding such a transport system has not yet been ...

PURPOSE OF REVIEW: The review summarizes the past year's literature regarding the regulation of gastric exocrine and endocrine secretion, both basic science and clinical. RECENT FINDINGS: Gastric acid secretion is an elaborate and dynamic process that is regulated by neural (efferent and afferent), hormonal (e.g. gastrin), and paracrine (e.g. histamine, ...

Neutral amino acid transporters of the SLC6 family are expressed at the apical membrane of kidney and/or small intestine, where they (re-)absorb amino acids into the body. In this review we present the results concerning the dependence of their apical expression with their association to partner proteins. We will in particular ...

In previous studies in freshwater tilapia (Oreochromis mossambicus), dietary supplementation with arachidonic acid (ArA; 20:4n - 6) had considerable, opposing effects on the main ion-transporting enzyme Na(+)/K(+)-ATPase in gills and kidneys and changed the release of osmoregulatory hormones, such as cortisol. The present study was performed to assess the influence of dietary ...

In conjunction with the routine role of delivering the active ingredient, carefully designed drug delivery vehicles can also provide ancillary functions that augment the overall efficacy of the system. Inspired by the ability of the cervicovaginal mucus to impede the movement of HIV virions at acidic pH, we have engineered ...

Ammonia is a neurotoxin involved in the pathogenesis of neurological conditions associated with hyperammonemia, including hepatic encephalopathy, a condition associated with acute--(ALF) or chronic liver failure. This article reviews evidence that apart from directly affecting the metabolism and function of the central nervous system cells, ammonia influences the passage of ...

A prodrug approach that employs the human apical sodium dependent bile acid transporter (hASBT) for absorption requires a recognition moiety for hASBT. Bile acids are natural ligands for hASBT, but are hormones with high molecular weight, such that a recognition moiety that is not a bile acid may be advantageous. ...

Human fetal metabolism is largely unexplored. Understanding how a healthy fetus achieves its fast growth rates could eventually play a pivotal role in improving future nutritional strategies for premature infants. To quantify specific fetal amino acid kinetics, eight healthy pregnant women received prior to elective cesarean section at term, continuous ...

OBJECTIVES: Deletion of the placental-specific P0 transcript of the insulin-like growth factor gene (Igf2) reduces placental growth from early pregnancy onwards. In Igf2 P0 knockout fetuses (P0), maternofetal flux of (14)C-methylaminoisobutyric acid ((14)C-MeAIB) mediated by system A amino acid transporter activity is increased at embryonic day 16 (E16), but this ...

Streptococcus pneumoniae is the leading cause of community-acquired pneumonia and results in over 1 million deaths each year worldwide. Asymptomatic colonization of the airway precedes disease, and acquisition of carbohydrates from the host environment is necessary for bacterial survival. We previously demonstrated that S. pneumoniae cleaves sialic acid from human ...

The bacterial small RNA GcvB has been known as a translational repressor of mRNAs encoding amino acid transporters and has been postulated to limit uptake of unnecessary amino acids under nutrient-rich conditions. In this issue of Molecular Microbiology, Sharma et al. (2011) provide evidence for a much broader role for GcvB ...

Radiohalogenated α-amino acids are a diverse and useful class tumor imaging agents suitable for positron emission tomography and single photon emission computed tomography. These tracers target the increased rates of amino acid transport exhibited by many tumor cells. The most established clinical use for radiolabeled amino acids is imaging primary ...

Sialin, the protein coded by SLC17A5, is responsible for membrane potential (Δψ)-driven aspartate and glutamate transport into synaptic vesicles as well as H(+) /sialic acid co-transport in lysosomes. Rodent sialin mutants harboring the mutations associated with Salla disease in humans did not transport aspartate and glutamate whereas H(+) /sialic acid ...

Cholestatic liver disorders encompass hepatobiliary diseases of diverse etiologies characterized by the accumulation of bile acids, bilirubin and cholesterol as the result of impaired secretion of bile. Members of the nuclear receptor (NR) family of ligand-modulated transcription factors are implicated in the adaptive response to cholestasis. NRs coordinately regulate bile ...

Central nervous system (CNS) drug delivery is a major challenge in drug development because the blood-brain barrier (BBB) efficiently restricts the entry of drug molecules into the CNS at sufficient amounts. The brain uptake of poorly penetrating drugs could be improved by utilizing the transporters at the BBB with prodrug ...

We investigated whether the uptake of triclopyr (3, 5, 6-trichloro-2-pyridinyloxyacetic acid) and dicamba (3,6-dichloro-2-methoxybenzoic acid) across the apical membrane of Caco-2 cells was mediated via proton-linked monocarboxylic acid transporters (MCTs). The uptake of triclopyr from the apical membranes was fast, pH-, temperature-, and concentration dependent, required metabolic energy to proceed, ...

The trafficking of fatty acids across the membrane and into downstream metabolic pathways requires their activation to CoA thioesters. Members of the fatty acid transport protein/very long chain acyl-CoA synthetase (FATP/Acsvl) family are emerging as key players in the trafficking of exogenous fatty acids into the cell and in intracellular ...

Nigella sativa seed oil was found to contain a modulator of Na,K-ATPase. Separation analyses combined with (1)H NMR and GCMS identified the inhibitory fraction as a mixture of oleic and linoleic acids. These two fatty acids are specifically concentrated in several medicinal plant oils, and have particularly been implicated in ...

An increasingly larger proportion of the oils used in diets for farmed fish are plant derived and rapeseed oil is most commonly used. Despite high dietary lipid levels and a marked change in lipid composition, the transport and metabolic fate of absorbed fatty acids is not fully understood in teleost ...