The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform
Masahiro Hayashi - One of the best experts on this subject based on the ideXlab platform.
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Effects of polyvinylpyrrolidone (K90) on membrane permeation via the Transcellular route in the rat jejunum
Journal of Pharmaceutical Investigation, 2021Co-Authors: Yusuke Takizawa, Yuka Furuno, Masahiro HayashiAbstract:Although pharmaceutical excipients do not affect the membrane permeation of active drugs, some have been shown to influence absorption-regulating factors. However, limited information is currently available on the effects of pharmaceutical excipients on membrane permeation via passive Transcellular transport, which is the main membrane permeation route of many drugs. We herein focused on polyvinylpyrrolidone (PVP) (K90), which is used as a diluent and binder in pharmaceutical formulations, and examined its effects on passive transport via the Transcellular route in the rat jejunum using the in vitro sac method. The membrane permeation of β-naphthol, a passive Transcellular marker, was increased by the co-existence of 0.02 w/v % PVP (K90). However, PVP (K90)-induced increases in membrane permeation were not observed following a pre-incubation with PVP (K90). Therefore, PVP (K90)-induced increases in membrane permeation may be attributed to a drug-excipient interaction, but not a mucosal membrane-excipient interaction. PVP (K90) affected membrane transport via the Transcellular route in the rat jejunum. However, since the coexistence of PVP (K90) did not influence membrane protein expression levels or cause membrane lesions, the absorption of active drugs may be regulated by the optimal application of PVP (K90).
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Effects of polyvinylpyrrolidone (K90) on membrane permeation via the Transcellular route in the rat jejunum
Journal of Pharmaceutical Investigation, 2021Co-Authors: Yusuke Takizawa, Yuka Furuno, Masahiro HayashiAbstract:Purpose Although pharmaceutical excipients do not affect the membrane permeation of active drugs, some have been shown to influence absorption-regulating factors. However, limited information is currently available on the effects of pharmaceutical excipients on membrane permeation via passive Transcellular transport, which is the main membrane permeation route of many drugs. Methods We herein focused on polyvinylpyrrolidone (PVP) (K90), which is used as a diluent and binder in pharmaceutical formulations, and examined its effects on passive transport via the Transcellular route in the rat jejunum using the in vitro sac method. Results The membrane permeation of β-naphthol, a passive Transcellular marker, was increased by the co-existence of 0.02 w/v % PVP (K90). However, PVP (K90)-induced increases in membrane permeation were not observed following a pre-incubation with PVP (K90). Therefore, PVP (K90)-induced increases in membrane permeation may be attributed to a drug-excipient interaction, but not a mucosal membrane-excipient interaction. Conclusion PVP (K90) affected membrane transport via the Transcellular route in the rat jejunum. However, since the coexistence of PVP (K90) did not influence membrane protein expression levels or cause membrane lesions, the absorption of active drugs may be regulated by the optimal application of PVP (K90).
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Sodium Nitroprusside Enhances Absorption in the Rat Jejunum via the Transcellular Route
The Journal of Membrane Biology, 2020Co-Authors: Yusuke Takizawa, Yoshifusa Tobe, Nasa Sakamoto, Junya Sakamoto, Masahiro HayashiAbstract:It was reported that nitric oxide (NO) donors increased the permeability of water-soluble compounds across intestinal membrane with neither loss of cell viability nor release of lactate dehydrogenase. Therefore, the detail mechanism of action of NO donors on the gastrointestinal membrane has yet to be clarified. We previously reported the possibility of the enhancing effect of the NO donor on the membrane permeability via Transcellular route. The purpose of this study is to clarify the mechanism of the membrane permeation-enhancing effect via the Transcellular route by sodium nitroprusside (SNP), which is one of the NO donors. The effect of SNP on membrane permeation was examined by the in vitro sac method using rat jejunum. SNP increased the membrane permeation of rhodamine 123 same as using N -acetyl- l -cysteine and dithiothreitol which removes unstirred water layer (UWL). Moreover, SNP increased the membrane permeation of antipyrine and β-naphthol, which are Transcellular markers. And it was also investigated the expression levels of mucins (MUCs) which are construction component of UWL and the slight change of MUCs expression by SNP was shown. It was suggested that the expression balance of MUCs is necessary to regulate Transcellular permeation, and SNP may affect to UWL. This finding was considered useful for highly lipophilic drugs for which membrane permeation is restricted by the UWL.
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NaPi-mediated Transcellular Permeation is the Dominant Route in Intestinal Inorganic Phosphate Absorption in Rats
Drug Metabolism and Pharmacokinetics, 2015Co-Authors: Mikio Tomita, Masahiro HayashiAbstract:Summary: Inorganic phosphate in food is absorbed two ways, the Transcellular route via the brush border membrane and the paracellular route via tight junctions. NaPi, a sodium-dependent inorganic phosphate transporter, is expressed in rat and human intestine. However, the relative contribution of NaPi to total carrier-mediated transport of physiological concentrations of inorganic phosphate in rat intestine is not clear. Here, we characterized inorganic phosphate transport across the rat small intestine using a voltage-clamp analysis which allowed the diffrentiation of inorganic phosphate permeation through these two (Transcellular and paracellular) routes. Results showed that, under a physiologically normal transmucosal electrical potential difference (about 2 mV), permeation of inorganic phosphate by the Transcellular route was greater than that by the paracellular route. Further, transport was significantly decreased by the addition to the incubation medium of phosphonoformic acid, a sodium-dependent phosphate transporter inhibitor, and severely inhibited under sodium-free conditions. Similar results were obtained without the voltage-clamp. Together, these results suggest that NaPi-mediated Transcellular permeation is the dominant route in the absorption of inorganic phosphate across the small intestine.
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Transcellular and paracellular contribution to transport processes in the colorectal route
Advanced Drug Delivery Reviews, 1997Co-Authors: Masahiro Hayashi, Mikio Tomita, Shoji AwazuAbstract:Abstract The two permeation pathways for colorectal drug absorption, the Transcellular and paracellular pathways, were examined. The Transcellular pathway is generally a principal route for drugs with some degree of lipophilicity. The contribution of the paracellular pathway to drug absorption is significant when absorption enhancers such as capric acid (C10) and decanoylcarnitine (DC) are used. The action mechanism of C10 on the Transcellular pathway was examined by membrane perturbation. The following in vitro effects of C10 on the paracellular pathway were observed: (i) an increase in the equivalent pore radius; (ii) an increase in the permeabilities of water-soluble non-electrolytes and ionic drugs; (iii) a decrease in the junctional resistance and an increase in the membrane capacitance. The action mechanism of C10 in the paracellular pathway was especially elucidated by stimulation to the contraction of the perijunctional actomyosin ring. Finally, an in vivo C10 effect was also observed, as an enhancement of rectal drug absorption from suppositories in rats.
José Eduardo Serrão - One of the best experts on this subject based on the ideXlab platform.
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Evidence for a Transcellular route for vitellogenin transport in the telotrophic ovary of Podisus nigrispinus (Hemiptera: Pentatomidae)
Scientific Reports, 2019Co-Authors: Mírian Quintão Assis, Virgínia Teles Dohanik, Leandro Licursi De Oliveira, José Cola Zanuncio, José Eduardo SerrãoAbstract:Vitellogenin is the main yolk precursor protein in insect oocytes. It is synthesized in the fat body and released into the hemolymph. To reach the oocyte surface, vitellogenin must cross a single layer of follicular epithelium cells. The transport of vitellogenin across the follicular epithelium has been suggested to occur through the enlarged intercellular spaces (patency) by a paracellular route or by endocytosis by follicular cells and release onto oocyte surface in a transcelluar route. In this study, we investigated whether vitellogenin transport in the meroistic telotrophic ovary of Podisus nigrispinus (Hemiptera) occurs via a paracellular or Transcellular route. Light and transmission electron microscopies showed that short cell–cell contacts with well-developed occluding septate junctions were present in follicular cells with patency. Immunofluorescence microscopy revealed the presence of vitellogenin receptors in the plasma membrane and of vitellogenin in the cytoplasm of follicular cells. Data suggest that cell–cell contacts serve as a barrier to large vitellogenin molecules and that this protein is transported via a Transcellular route of receptor-mediated endocytosis.
Markus Bleich - One of the best experts on this subject based on the ideXlab platform.
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AVP dynamically increases paracellular Na^+ permeability and Transcellular NaCl transport in the medullary thick ascending limb of Henle’s loop
Pflügers Archiv - European Journal of Physiology, 2017Co-Authors: Nina Himmerkus, Allein Plain, Rita D. Marques, Svenja R. Sonntag, Alexander Paliege, Jens Leipziger, Markus BleichAbstract:The medullary thick ascending limb of Henle’s loop (mTAL) is crucial for urine-concentrating ability of the kidney. It is water tight and able to dilute the luminal fluid by active Transcellular NaCl transport, fueling the counter current mechanism by increasing interstitial osmolality. While chloride is exclusively transported Transcellularly, approx. 50% of sodium transport occurs via the paracellular route, driven by the lumen-positive transepithelial potential. Antidiuretic hormone (AVP) is known to increase active NaCl transport to support collecting duct water reabsorption. Here, we investigated the concomitant effects of AVP on the paracellular properties of mTAL. Freshly isolated mouse mTALs were perfused and electrophysiological Transcellular and paracelluar properties were assessed in a paired fashion before and after AVP stimulation. In addition, the same parameters were measured in mice on a water-restricted (WR) or water-loaded (WL) diet for 5 days. Acute ex vivo stimulation as well as long-term in vivo water restriction increased equivalent short circuit current as a measure of active Transcellular NaCl transport. Intriguingly, in both experimental approaches, this was accompanied by markedly increased paracellular Na^+ selectivity. Thus, AVP is able to acutely regulate paracellular cation selectivity in parallel to Transcellular NaCl transport, allowing balanced paracellular Na^+ absorption under an increased transepithelial driving force.
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avp dynamically increases paracellular na permeability and Transcellular nacl transport in the medullary thick ascending limb of henle s loop
Pflügers Archiv: European Journal of Physiology, 2017Co-Authors: Nina Himmerkus, Allein Plain, Rita D. Marques, Svenja R. Sonntag, Alexander Paliege, Jens Leipziger, Markus BleichAbstract:The medullary thick ascending limb of Henle’s loop (mTAL) is crucial for urine-concentrating ability of the kidney. It is water tight and able to dilute the luminal fluid by active Transcellular NaCl transport, fueling the counter current mechanism by increasing interstitial osmolality. While chloride is exclusively transported Transcellularly, approx. 50% of sodium transport occurs via the paracellular route, driven by the lumen-positive transepithelial potential. Antidiuretic hormone (AVP) is known to increase active NaCl transport to support collecting duct water reabsorption. Here, we investigated the concomitant effects of AVP on the paracellular properties of mTAL. Freshly isolated mouse mTALs were perfused and electrophysiological Transcellular and paracelluar properties were assessed in a paired fashion before and after AVP stimulation. In addition, the same parameters were measured in mice on a water-restricted (WR) or water-loaded (WL) diet for 5 days. Acute ex vivo stimulation as well as long-term in vivo water restriction increased equivalent short circuit current as a measure of active Transcellular NaCl transport. Intriguingly, in both experimental approaches, this was accompanied by markedly increased paracellular Na+ selectivity. Thus, AVP is able to acutely regulate paracellular cation selectivity in parallel to Transcellular NaCl transport, allowing balanced paracellular Na+ absorption under an increased transepithelial driving force.
Steven J Ackerman - One of the best experts on this subject based on the ideXlab platform.
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systematic evaluation of Transcellular activities of secretory phospholipases a2 high activity of group v phospholipases a2 to induce eicosanoid biosynthesis in neighboring inflammatory cells
Journal of Biological Chemistry, 2006Co-Authors: Gihani T Wijewickrama, Jinhahn Kim, Young Jun Kim, Alexandra Abraham, Bharath Ananthanarayanan, Mark A Kwatia, Steven J Ackerman, Wonhwa ChoAbstract:Abstract The mechanisms by which secretory phospholipase A2 (PLA2) exerts cellular effects are not fully understood. To elucidate these mechanisms, we systematically and quantitatively assessed the activities of human group IIA, V, and X PLA2s on originating and neighboring cells using orthogonal fluorogenic substrates in various mixed cell systems. When HEK293 cells stably expressing each of these PLA2s were mixed with non-transfected HEK293 cells, group V and X PLA2s showed strong Transcellular lipolytic activity, whereas group IIA PLA2 exhibited much lower Transcellular activity. The Transcellular activity of group V PLA2 was highly dependent on the presence of cell surface heparan sulfate proteoglycans of acceptor cells. Activation of RBL-2H3 and DLD-1 cells that express endogenous group V PLA2 led to the secretion of group V PLA2 and its Transcellular action on neighboring human neutrophils and eosinophils, respectively. Similarly, activation of human bronchial epithelial cells, BEAS-2B, caused large increases in arachidonic acid and leukotriene C4 release from neighboring human eosinophils. Collectively, these studies show that group V and X PLA2s can act Transcellularly on mammalian cells and suggest that group V PLA2 released from neighboring cells may function in triggering the activation of inflammatory cells under physiological conditions.
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systematic evaluation of Transcellular activities of secretory phospholipases a2 high activity of group v phospholipases a2 to induce eicosanoid biosynthesis in neighboring inflammatory cells
Journal of Biological Chemistry, 2006Co-Authors: Gihani T Wijewickrama, Alexandra Abraham, Bharath Ananthanarayanan, Mark A Kwatia, Younsang Oh, Steven J AckermanAbstract:Abstract The mechanisms by which secretory phospholipase A2 (PLA2) exerts cellular effects are not fully understood. To elucidate these mechanisms, we systematically and quantitatively assessed the activities of human group IIA, V, and X PLA2s on originating and neighboring cells using orthogonal fluorogenic substrates in various mixed cell systems. When HEK293 cells stably expressing each of these PLA2s were mixed with non-transfected HEK293 cells, group V and X PLA2s showed strong Transcellular lipolytic activity, whereas group IIA PLA2 exhibited much lower Transcellular activity. The Transcellular activity of group V PLA2 was highly dependent on the presence of cell surface heparan sulfate proteoglycans of acceptor cells. Activation of RBL-2H3 and DLD-1 cells that express endogenous group V PLA2 led to the secretion of group V PLA2 and its Transcellular action on neighboring human neutrophils and eosinophils, respectively. Similarly, activation of human bronchial epithelial cells, BEAS-2B, caused large increases in arachidonic acid and leukotriene C4 release from neighboring human eosinophils. Collectively, these studies show that group V and X PLA2s can act Transcellularly on mammalian cells and suggest that group V PLA2 released from neighboring cells may function in triggering the activation of inflammatory cells under physiological conditions.
Mariedominique Filippi - One of the best experts on this subject based on the ideXlab platform.
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Metabolic Remodeling of Neutrophils at Inflammatory Site Drives Invadosome Formation Favoring Transcellular Migration
Blood, 2017Co-Authors: Chanchal Sur Chowdhury, Elizabeth Wareham, Sunil Kumar, Ashwini S. Hinge, Sribalaji Lakshmikanthan, Magdalena Chrzanowska-wodnicka, Mariedominique FilippiAbstract:Abstract Neutrophils traffic in and out of underlying vascular bed during hematopoiesis and immunosurveillance. However, during inflammatory conditions such as ischemia reperfusion injury or atherosclerosis, excessive neutrophil infiltration into tissue drives disease pathogenesis. Yet, the relationship between neutrophil transmigration and inflammation is ill-defined. Neutrophil extravasation can occur either between two endothelial cells (paracellular) or directly through an endothelial cell body (Transcellular). During Transcellular migration, neutrophils interact with underlying endothelial cells (EC) via invadosomal structures, which forms a 'pore' into endothelial cell membrane, thus facilitating neutrophil migration through EC body. We have recently reported that deficiency in Rap1b, a member of Ras superfamily of GTPase, enhanced neutrophil Transcellular migration, invadosomal structures and metalloproteinase (MMP) release (Kumar et al, JEM, 2014), in a manner dependent on high Akt activity. Further, Rap1-deficiency increased neutrophil recruitment to inflamed lungs and enhanced susceptibility to endotoxin shock, suggesting mode of neutrophil migration may influence inflammatory outcome. Here, to further understand which factors drive neutrophil Transcellular migration, we analyzed protein content of Rap1b-/- invadosomal structures during Transcellular diapedesis. For this, neutrophils were stimulated in transwell filters of 1µM pore size, with FMLP placed in the lower chamber, allowing only invadosomal protrusions into the pores. After removing the cell body from top of the filter, mass spectrometric analysis was performed on the invadosomal fraction. About 680 proteins were identified in protrusions isolated from WT or Rap1b-/- neutrophils. As expected, majority of them were cytoskeleton and adhesion proteins. Interestingly, Rap1b-/- invadosomal structures contained more enzymes of glycolytic pathways, including HK1, Lactate dehydrogenase A (LDHA) and phosphoglycerate kinase1 (PGK1). Immunofluorescent staining and western blotting confirmed this observation. Importantly, glycolytic enzymes were present at the tip of the protrusions in colocalization with F-actin suggesting site specific glycolytic activity, raising the hypothesis that metabolic remodeling may influence the route of neutrophil migration. LDHA converts pyruvate to lactate and subsequent milieu acidification, which can then cause MMP activation. Consistently, Rap1b-/- neutrophils exhibited increased uptake of glucose analogue (2-NBDG) and concurrent intracellular acidification, as detected by pH sensitive dye. To investigate the importance of LDHA activity during Transcellular migration, Rap1b-/- neutrophils were treated with a specific pharmacological inhibitor of LDHA, namely FX11. In vitro, FX11 treatment significantly decreased Transcellular migration of Rap1b-/- neutrophils. It also reduced invadosome formation of Rap1b-/- neutrophils within transwell pores, as well as neutrophil acidity and MMP activity. Furthermore, during neutrophil-endothelial cell interactions in vitro, Rap1b-/- neutrophils caused F-actin depolymerization in EC, likely facilitating Transcellular passage; this was inhibited by FX11. To examine its effect in vivo, under same inflammatory microenvironment, Rap1b-/- and WT neutrophils were tagged with cell tracker dyes and transferred to recipient mice, treated with FX11 or DMSO control. Ear microvasculature was stimulated with FMLP and labeled with PECAM antibody to visualize EC junctions. Rap1b-/- neutrophils migrated out of vessels at higher frequency than WT cells, which was abrogated by FX11 treatment. Moreover, treatment with FX11 reduced the number of Rap1b-/- neutrophils located away from EC junction (Transcellular route), in vivo. These results suggest enhanced local glycolytic metabolism and LDHA activity could act as critical regulators of Transcellular migration. Increase in extracellular acidification mediated by LDHA activity, could affect endothelial permeability and alter neutrophil migratory behavior affecting outcome of inflammation. Since milieu acidification plays a major role in ischemic damage to the heart, these findings may be clinically important for our understanding of hyperinflammatory disorders. Disclosures No relevant conflicts of interest to declare.
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leukocyte Transcellular diapedesis rap1b is in control
Tissue barriers, 2015Co-Authors: Mariedominique FilippiAbstract:The neutrophil transmigration across the blood endothelial cell barrier represents the prerequisite step of innate inflammation. It is well known that neutrophils cross the endothelial barrier by transmigrating at the endothelial cell junction (‘paracellular’). However, in vivo and in vitro evidence have clearly demonstrated occurrence of an alternate mode of migration directly through the endothelial cell body (‘Transcellular’). Despite our knowledge on mechanisms of transendothelial migration, it remains unclear which factors determine distinct modes of migration. We recently found that the Ras-like Rap1b GTPase limits neutrophil Transcellular migration. Rap1b restrains Transcellular migration by suppressing Akt-driven invasive protrusions while leaving the paracellular route unaffected. Furthermore, Rap1b limits neutrophil tissue infiltration in mice and prevents hyper susceptibility to endotoxin shock. These findings uncover a novel role for Rap1b in neutrophil migration and inflammation. Importantly,...
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Leukocyte Transcellular diapedesis: Rap1b is in control.
Tissue barriers, 2015Co-Authors: Mariedominique FilippiAbstract:The neutrophil transmigration across the blood endothelial cell barrier represents the prerequisite step of innate inflammation. It is well known that neutrophils cross the endothelial barrier by transmigrating at the endothelial cell junction ('paracellular'). However, in vivo and in vitro evidence have clearly demonstrated occurrence of an alternate mode of migration directly through the endothelial cell body ('Transcellular'). Despite our knowledge on mechanisms of transendothelial migration, it remains unclear which factors determine distinct modes of migration. We recently found that the Ras-like Rap1b GTPase limits neutrophil Transcellular migration. Rap1b restrains Transcellular migration by suppressing Akt-driven invasive protrusions while leaving the paracellular route unaffected. Furthermore, Rap1b limits neutrophil tissue infiltration in mice and prevents hyper susceptibility to endotoxin shock. These findings uncover a novel role for Rap1b in neutrophil migration and inflammation. Importantly, they offer emerging evidences that paracellular and Transcellular migration of neutrophils are regulated by separate mechanisms. Here, we discuss the mechanisms of neutrophil transmigration and their clinical importance for vascular integrity and innate inflammation.
