Effect Of L-fucose Research Articles

L-Fucose promotes enteric nervous system regeneration in type 1 diabetic mice by inhibiting SMAD2 signaling pathway in enteric neural precursor cells

BackgroundDiabetes can lead to extensive damage to the enteric nervous system (ENS), causing gastrointestinal motility disorders. However, there is currently a lack of effective treatments for diabetes-induced ENS damage. Enteric neural precursor cells (ENPCs) closely regulate the structural and functional integrity of the ENS. L-Fucose, is a dietary sugar that has been showed to effectively ameliorate central nervous system injuries, but its potential for ameliorating ENS damage and the involvement of ENPCs in this process remains uncertain.MethodsGenetically engineered mice were generated for lineage tracing of ENPCs in vivo. Using diabetic mice in vivo and high glucose-treated primary ENPCs in vitro, the effects of L-Fucose on the injured ENS and ENPCs was evaluated by assessing gastrointestinal motility, ENS structure, and the differentiation of ENPCs. The key signaling pathways in regulating neurogenesis and neural precursor cells properties, transforming growth factor-β (TGF-β) and its downstream signaling pathways were further examined to clarify the potential mechanism of L-Fucose on the injured ENS and ENPCs.ResultsL-Fucose improved gastrointestinal motility in diabetic mice, including increased defecation frequency (p < 0.05), reduced total gastrointestinal transmission time (p < 0.001) and bead expulsion time (p < 0.05), as well as enhanced spontaneous contractility and electric field stimulation-induced contraction response in isolated colonic muscle strips (p < 0.001). The decrease in the number of neurons and glial cells in the ENS of diabetic mice were reversed by L-Fucose treatment. More importantly, L-Fucose treatment significantly promoted the proportion of ENPCs differentiated into neurons and glial cells both in vitro and in vivo, accompanied by inhibiting SMAD2 phosphorylation.ConclusionsL-Fucose could promote neurogenesis and gliogenesis derived from ENPCs by inhibiting the SMAD2 signaling, thus facilitating ENS regeneration and gastrointestinal motility recovery in type 1 diabetic mice.7Zzihak_jncvcnfCNwCPXsVideo

L-Fucose inhibits the progression of cholangiocarcinoma by causing microRNA-200b overexpression.

Cholangiocarcinoma (CCA) is a malignant biliary tract tumor with an extremely poor prognosis. There is an urgent demand to explore novel therapeutic strategies. L-fucose has been confirmed to participate in anti-inflammation and antitumor activities. However, the effect of L-fucose on the progression of CCA has not been well investigated. This study aimed to determine whether L-fucose induced the inhibition of CCA and its possible mechanism. The anti-growth activity was determined using Cell Counting Kit-8 assay, colony formation assays, Annexin V-fluorescein isothiocyanate/propidium iodide (FITC/PI) assay, and cell cycle analysis. The anti-metastasis activity was determined by wound healing, transwell, and invasion assays. The anti-angiogenesis activity was determined by tube formation and transwell assays. MicroRNAs that may be involved in the L-fucose-induced CCA inhibition was analyzed using bioinformatics methods. The preclinical therapeutic efficacy was mainly estimated by ultrasound in xenograft nude mouse models. Differences were analyzed via Student's t test or one-way analysis of variance. L-Fucose induced apoptosis and G0/G1 cell cycle arrest, inhibited cell epithelial-mesenchymal transition of CCA cells, and additionally inhibited tube formation of human umbilical vein endothelial cells (HUVECs) in a dose-dependent manner, leading to a decrease in cell proliferation, metastasis, and angiogenesis. Mechanistically, L-fucose induced microRNA-200b (miR-200b) upregulation, and mitogen-activated protein kinase 7 (MAPK7) downregulation was found to be targeted by miR-200b, with decreased cell proliferation and metastasis. Additionally, phosphorylated signal transducer and activator of transcription 3 was found to be downregulated after L-fucose treatment. Finally, in vivo experiments in CCA xenograft models also confirmed the antitumor properties of L-fucose. L-Fucose inhibited the progression of CCA via the miR-200b/MAPK7 and signal transducer and activator of transcription 3 signaling pathways.

Characterization of the response of Escherichia coli to l-fucose in bacterial swimming motility.

l-Fucose, as a monosaccharide in nature, plays a crucial role in bacteria colonization. Escherichia coli (E. coli), as a common microorganism in environment, utilize bacterial flagellar motor to drive the rotation of flagella, which is regulated by chemotactic signal transduction signals. Yet the effect of l-fucose to bacterial motility remains unclear. The effect of l-fucose on the swimming motility of bacteria was investigated from the level of single flagellar motor to individual cell and cell population by employing a bead assay, a high-throughput 2D tracking assay and a high-throughput dark-field flicker microscopy. The results showed that the swimming motility of the bacteria cultured with l-fucose was decreased, while the tumble frequency increased. Furthermore, the behavioral alterations of bacteria affected by l-fucose were directly reveled by measuring the cell distribution of bacteria swimming near surfaces and bacterial surface adhesion, suggesting that l-fucose promotes bacterial surface aggregation and surface adhesion. The effect of l-fucose on bacterial swimming motility characterized in this study are consistent with the key role that l-fucose plays in bacterial colonization.

Abstract B24: Using L-fucose to render melanomas immune hot: Roles of melanoma HLA-DRB1 and CD4+T cell-mediated antitumor immunity

Abstract Responsiveness to immunotherapies is limited in melanoma to subsets of patients. Despite attempts to improve responsiveness to immunotherapies by testing combination therapies, patients often experience significant adverse events that require the termination of treatment. Although causes of nonresponsiveness remain unclear and the subject of active investigation, a commonality among refractory tumors is low pretreatment levels of tumor-infiltrating lymphocytes (TILs). Thus, studies aiming to elucidate the interactions between melanoma and immune cells and to increase TIL levels are anticipated to improve therapies. We previously reported that fucosylation (the post-translational modification of proteins with the dietary plant sugar L-fucose), is altered in melanoma. Increasing fucosylation levels in melanoma—genetically or with oral L-fucose—suppresses tumor growth, metastasis, and increases TILs in immune competent mouse models of melanoma (Lau et al., 2015). The mechanisms underlying how melanoma fucosylation appears to trigger antitumor immunity are unclear. Here, we identified TIL subpopulations triggered by fucosylation to mediate tumor suppression and a key molecular mechanism. In NRAS- and BRAF-mutant melanoma models, dietary L-fucose suppressed tumor growth by ~50-60% and increased TILs by ~10-50-fold. Of all TIL subpopulations examined, CD3+ T cells were most increased by L-fucose, doubling or increasing by 15-fold, in NRAS- or BRAF-mutant models, respectively. Depletion of CD4+ T cells abrogated L-fucose-triggered TIL increases and tumor suppression, indicating that CD4+ T cells are central for antitumor immune effects of L-fucose. We identified the Class II MHC protein HLA-DRB1 as expressed and fucosylated in melanoma cells and confirmed its requirement for L-fucose-triggered, CD4+ T cell-dependent tumor suppression in vivo. Roles of HLA-DRB1 fucosylation in melanoma, effects on CD4+ T cell biology, and how L-fucose can enhance immunotherapies will be discussed. Our studies highlight how L-fucose supplementation can render tumors “immune hot” and represents a potential therapeutic strategy for improving immunotherapies. Citation Format: Daniel K. Lester, Matt Mercurio, Pasquale Innamorato, Kodumudi Krithika, Williamson Danial, Watson Gregory, Pilon-Thomas Shari, Messina Jane, Kerri L. Thomas, Susan McCarthy, Joseph Markowitz, Robert Haltiwanger, Eric Lau. Using L-fucose to render melanomas immune hot: Roles of melanoma HLA-DRB1 and CD4+T cell-mediated antitumor immunity [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B24.

Pharmacology of skin aging. Stimulation of glycosaminoglycan biosynthesis by L-fucose and fucose-rich polysaccharides, effect of in vitro aging of fibroblasts

The effect of L-fucose and fucose-rich polysaccharides (FROP-s [Biomed. Pharmacother., 2003; 57: 187–94]) was investigated, using human skin fibroblast cultures at several passages. The cells were incubated with radioactive glucosamine for 24 h, followed by the determination of individual glycosaminoglycans (GAG-s) by selective hydrolysis using specific enzymes. The effect of L-fucose and of FROP-3 [Biomed. Pharmacother., in 2003; 57: 187–94], both at 1 and 10 μg/ml, added to the culture medium, was investigated. L-Fucose stimulated the incorporation of the tracer in heparan sulfates by fibroblasts at the ninth passage by 20%. FROP-3 stimulated incorporation in keratan sulfates by 45% by fibroblasts of the fifth passage. This effect was identical at both concentrations tested. For fibroblasts at the ninth passage FROP-3 stimulated incorporation in dermatan sulfate. This effect was dose dependent of the order of +67% at 1 μg/ml and +128% at 10 μg/ml. Incorporation in hyaluronan was also stimulated by about +27%. These stimulations of GAG-biosynthesis might play a role in the increase of total skin thickness of hairless rats treated with L-fucose, as well as in several other favorable results recorded for FROP-3 such as the increased hydration (resistance to pressure) and elasticity of human skin (Robert C, Robert AM, Robert L).

Effect of L-fucose and fucose-rich polysaccharides on elastin biosynthesis, in vivo and in vitro

With increasing age elastic fibres in human skin are progressively lysed and skin elasticity is also decreasing. Still there is an age-dependent increase of elastic fibre surface density, mostly due to an alteration of the fibres. The present experiments were undertaken to explore if L-fucose and fucose-rich polysaccharides (FROP-s) could influence elastin biosynthesis. We show here, that topical application of a fucose-containing preparation to the skin of hairless rats increased after 4 weeks the elastic fibre surface density by about 40%, shown by quantitative morphology. Using human skin fibroblasts in explant cultures, the addition of L-fucose or of FROP-3 increased the biosynthesis of immunoprecipitable tropoelastin by about 40%. No increase was found however of desmosine–isodesmosine in skin explant cultures after 72 h of incubation. The effect of L-fucose and FROP-3 on the biosynthesis of collagen and non-collagen proteins excreted by the skin explant cultures was also investigated. L-Fucose, but not FROP-3, decreased collagen biosynthesis but both increased non-collagen protein biosynthesis. These results show that L-fucose and FROP-3 stimulate tropoelastin biosynthesis in vitro, and elastic fibre formation in vivo. This stimulation concerns also several non-collagen proteins secreted by skin explant cultures. Elastic fibre formation necessitates the simultaneous synthesis of several microfibrillar glycoproteins as well as of tropoelastin. The increased elastic fibre density in the in vivo experiments suggests that this is indeed achieved by L-fucose and FROP-3, further demonstrating their efficiency in the control of age-dependent modifications of connective tissues in general and of skin in particular.

Effects of L-fucose and fucose-rich oligo- and polysaccharides (FROP-s) on collagen biosynthesis by human skin fibroblasts. Modulation of the effect of retinol, ascorbate and α-tocopherol

The action of L-fucose and a fucose-rich oligosaccharide (FROP-3) on skin explant cultures and fibroblast cell cultures, alone or together with three vitamins (A, C, E, often used in topical preparations) was studied, using as criteria collagen accumulation and collagen and non-collagen protein biosynthesis. In order to confirm the results observed, several variants of the chemical procedure were used. Collagen accumulation in cell cultures and 3H-proline incorporation in proteins and collagen gave comparable results. L-Fucose produced a slight but significant inhibition of collagen accumulation and of incorporation of radioactive proline in cell associated collagen and also modified the ratio of excreted (soluble) to cell- or tissue-bound collagen and non-collagen proteins. The oligosaccharide (FROP-3) did not produce a comparable inhibition of collagen biosynthesis. Both L-fucose and FROP-3 modulated the action of the two above-mentioned vitamins in most experimental conditions used. The combined action of the three vitamins (all-trans retinol, ascorbate, α-tocopherol) with L-fucose and even more so with FROP-3 can be considered as favourable for the modulation of the biosynthetic activity of fibroblasts.

Effect of L-fucose and fucose-rich oligo- and polysaccharides (FROP-s) on skin aging: penetration, skin tissue production and fibrillogenesis

Skin thickness is decreasing with age. This loss concerns both dermis and epidermis, cells and extracellular matrix. We could show here that percutaneous application of an L-fucose-containing preparation produced an increase of skin thickness and a densification of collagen bundles. We also could show that 3H-L-fucose penetrates in the dermis, a prerequisite for the abovementioned favorable pharmacological activities. These results, together with the previous favorable activities on the downregulation of matrix-degrading enzymes, free radical scavenging and increased cell proliferation confirm the favorable action of fucose and fucose-rich polysaccharides (FROP-s) on the skin by slowing down its aging.

Enhancement of glutamate release by L-fucose changes effects of glutamate receptor antagonists on long-term potentiation in the rat hippocampus.

In previous studies L-fucose has been shown to facilitate long-term memory formation and to enhance and prolong long-term potentiation (LTP). To search for possible presynaptic or postsynaptic mechanisms that are affected by L-fucose, we examined the effect of L-fucose on (1) inhibition of LTP induction via glutamate receptors by antagonists, (2) paired-pulse facilitation, and (3) presynaptic transmitter release. Coapplication of 0.2 mM L-fucose with the competitive N-methyl-D-aspartate (NMDA) receptor antagonist, D-2-amino-5-phosphonovalerate (AP5), or coapplication of 0.2 mM L-fucose in the presence of an inhibitor for class I/II metabotropic glutamate receptors, (S)-alpha-methyl-4-carboxyphenylglycine (MCPG), reversed LTP blockade in the CA1-region of hippocampal slices. In contrast, L-fucose had no effect on the LTP blockade by the noncompetitive NMDA ion-channel blocker (5R,10S)-(+)-5-Methyl-10, 11-dihydro-5H-dibenzo[a,d]cyclohepten-5, 10-imine hydrogen maleate (MK-801). Paired-pulse facilitation, which is a primarily presynaptic phenomenon of short-term plasticity, was decreased in the presence of 0.2 mM L-fucose. Furthermore, L-fucose enhanced the K(+)-stimulated release of [(3)H]-D-aspartate from preloaded hippocampal slices in a concentration-dependent manner. These observations demonstrate an influence of L-fucose on transmitter release that in turn can increase transmitter availability at postsynaptic glutamate receptors. This effect of L-fucose may contribute to the LTP facilitation seen in vitro and in vivo as well as to improvement in memory formation.

Effect of l-fucose and d-glucose concentration on l-fucoprotein metabolism in human Hep G2 cells and changes in fucosyltransferase and α- l-fucosidase activity in liver of diabetic rats

l-Fucose is a monosaccharide that is present at low concentrations in serum and is a normal constituent of glycoproteins. In some pathological conditions, such as cancer, rheumatoid arthritis, and diabetes, there is an abnormal fucosylation of acute phase serum proteins. Because most serum proteins are produced in the liver, we have examined l-fucose accumulation, metabolism, and secretion of l-fucose-containing proteins in human Hep G2 liver cells. Accumulation of l-fucose by Hep G2 cells approached 3.5 nmol/mg protein after a 48 h incubation. This accumulation appears similar to accumulation in other cells, which we have shown occurs via a specific transport protein. Exogenous l-fucose was incorporated into protein in both O- and N-linked glycosidic linkages. After a 48 h incubation, 61% of the accumulated l-fucose was incorporated into protein and secreted into the medium, whereas 39% of the l-fucose remaining in the cells was incorporated into integral membrane proteins. Utilizing reverse-phase high-performance liquid chromatographic separation of l-[5,6- 3H]fucose-containing proteins and detection by scintillation counting, we determined that two major fucoproteins and numerous minor fucoproteins were produced and secreted by normal Hep G2 cells. This elution profile was unchanged when glucose-conditioned cells were examined. By size-separating secreted proteins by nondenaturing HPLC we determined that the size of the two major fucoproteins were ≈60 and ≈100 kDa. In these studies we also examined the effect of diabetes on hepatic fucosyltransferase and serum α- l-fucosidase activity and found that the activity of these enzymes is increased by 40 and 100%, respectively in diabetic rats.

L‐fucose reduces collagen and noncollagen protein production in cultured cerebral microvessel endothelial cells

L-fucose is a monosaccharide which is present in low concentrations in normal serum but is increased in diabetes, cancer, and inflammatory diseases. The contribution that abnormal L-fucose levels make to the progression of these disorders is unknown. In a previous study we showed that increased L-fucose concentration reduced proliferation and proteoglycan production by cultured cerebral microvessel endothelial cells. In the present study we show that exposing cerebral microvessel endothelial cells for 2 weeks to medium containing an increased concentration of L-fucose causes a significant decrease in collagen and to a lesser extent noncollagen protein production. The effect of L-fucose on collagen and noncollagen protein production is concentration-dependent: 1 mM L-fucose causes a significant decrease in collagen production but has no effect on noncollagen protein production; a 5 mM L-fucose concentration causes a maximum decrease in both collagen and noncollagen protein production. This defect is unrelated to the reduction in myo-inositol uptake caused by L-fucose and is not prevented by aminoguanidine. Collagen production can be improved by restoring L-fucose-conditioned cells to normal medium. Culturing cells for 2 weeks in medium containing 10 mM L-fucose resulted in a 50% decrease in collagen production, which was restored to 75% of control after cells were transferred to normal medium for 7 days. In contrast, noncollagen protein production was totally restored after 3 days in normal medium. Increasing levels of L-fucose in serum of rats also resulted in a decrease in collagen production. Collagenase digestible incorporation of L-[2,3,4,5-3H]proline into protein of the articular cartilage from rats fed a diet containing 20% L-fucose for 3 weeks was reduced by about 40% compared to rats fed a normal diet. The decrease in collagen production in L-fucose fed rats was less than the reduction that occurred in streptozotocin-induced diabetic rats. These data suggest that changes in L-fucose concentration itself may be a factor in the regulation of collagen production.

L-Fucose blocks MIF/MAF priming of rabbit alveolar macrophages for a PMA-induced oxidative response

The effect of l-fucose on the priming of AM from normal adult rabbits and their subsequent chemiluminescent (CL) responses to phorbol myristate acetate (PMA) was investigated. It was observed that 12.5 m M l-fucose, but not d-fucose, blocked the “spontaneous” priming of normal AM during an 18-hr incubation period in serum-free RPMI 1640 medium by about 40% ( P < 0.01) as detected by their CL responses to a PMA challenge. In addition, the optimal concentration of l-fucose (12.5 m M) blocked MIF/MAF priming during the 3- or 18-hr incubaion period by 71 or 93% ( P < 0.05), respectively, as determined by their CL responses following PMA challenge. It is of particular significance that d-fucose was inactive. These results, together with previously published data, indicate that l-fucose (a) blocks priming of AM for an oxidative response, (b) stimulates random migration of AM, and (c) reverses migration inhibition produced by migration inhibition factor.

Effect of L-fucose on brain protein metabolism and retention of a learned behavior in rats.

The intraperitoneal or intraventricular application of L-fucose (100 mg/kg or 75 microgram, respectively) prior to training in shuttle box avoidance as well as in shock-motivated brightness discrimination in rats significantly improved the retention of learned behavior 24 hr later. The application of D-fucose was without influence on retention. In naive animals, intraventricularly applied L-fucose (75-200 microgram) caused an increase in the rate of protein synthesis in the hippocampus, resulting in a significant increase in total proteins of this brain structure, mainly attributed to the Tris-insoluble protein fractions. The results are discussed in terms of an activation of glycoprotein formation by increasing supply with L-fucose.

Studies on Cellular Receptors for Lymphokines

Abstract In contrast to previous reports, L-rhamnose as well as L-fucose is capable of inhibiting guinea pig migration inhibition factor (MIF) activity. These sugars also inhibit the activity of macrophage chemotactic and neutrophil chemotactic factors. Thus, fucose is not a specific inhibitor of MIF, nor is its activity confined to that lymphokine. Preincubation of L-fucose or L-rhamnose with the lymphokines was required for inhibition of chemotactic activity. This finding, as well as the results of dose-response experiments, suggest that the mechanism of chemotactic inhibition is similar to the mechanism of inhibition of MIF by monosaccharides; i.e., that the lymphokines possess receptor sites that recognize cell sites bearing a structural or conformational similarity to these sugars. In contrast, L-xylose, the only other sugar found inhibitory in the present study, appeared to exert its activity by a direct effect on the target cells themselves rather than by interaction with the mediator. Dose-response studies demonstrate that the effect of L-fucose on inhibition of either lymphokine activity is inversely proportional to the amount of lymphokine activity initially present. A major finding that emerged from the present study is that the monosaccharide inhibition of inflammatory mediator activity appears to be confined to either lymphokines themselves or cytokines (lymphokine-like factors derived from nonlymphoid cells). Three other biologic mediators with chemotactic activity, fragments from trypsin-treated C3 and C5, and bacterial factor, could not be inhibited by either L-fucose or L-rhamnose. The apparent inhibitory effect of L-xylose for bacterial factor activity does not negate this conclusion, since as stated above, this sugar appears to interact with the target cell rather than the mediator. Aside from theoretical considerations, this finding may be of considerable practical importance since it could provide a simple way to distinguish different sources of chemotactic activity in complex biologic mixtures such as serum or tissue extracts. Based upon current data and the results of previous studies, we have postulated that the inflammatory mediators (lymphokines) have two binding sites, one to allow for recognition of the appropriate target cells, and the other which determines the specific biologic activity.

The effect of L-fucose on rat mammary tumor growth. II. In vitro studies.

AbstractDifferent concentrations of L‐fucose uniformly produced a suppression in the growth rate and a change in the morphology of cells grown in tissue culture. The inhibition of growth of these malignant cells was found to he concentration dependent with 100% inhibition of growth at a concentration of 50 mg fucose per milliliter of medium and 60% inhibition at a concentration of 12.5 mg fucose per milliliter medium. Using other sugars that are components of the glycoproteins, it was shown that mannose and galactose could also depress the rate of growth of these tumor cells in culture. When 0.05 ml of packed tumor cells used in these experiments was resuspended in 1 ml of medium and injected into a rat, a tumor grew at the site of injection. This new tumor exhibited similar growth characteristics and showed the same histological appearance as the tumor from which the cell line was derived.