scholarly journals Transport of Axonal Enzymes in Surviving Segments of Frog Sciatic Nerve

1972 ◽  
Vol 60 (4) ◽  
pp. 388-405 ◽  
Author(s):  
Lester M. Partlow ◽  
C. David Ross ◽  
Ratna Motwani ◽  
David B. McDougal
Keyword(s):  
Sciatic Nerve ◽  
Enzyme Activities ◽  
Cholinesterase Activity ◽  
Total Content ◽  
Mitochondrial Enzymes ◽  
Choline Acetylase ◽  
Glutamic Dehydrogenase ◽  
Frog Sciatic Nerve

Redistribution of axonal enzymes as a function of time in vitro was studied in an unbranched segment of frog sciatic nerve. Cholinesterase activity moved peripherally at a rate of 99 mm/day and centrally at 19 mm/day. One-quarter of the total nerve content of the enzyme was estimated to be in motion, one-eighth in each direction. Mitochondrial enzymes (hexokinase and glutamic dehydrogenase) moved peripherally at 20–31 mm/day, centrally at 11–20 mm/day. Only 10% of the total content of these mitochondrial enzymes was in motion. No movement of choline acetylase or 6-phosphogluconic dehydrogenase activity was seen even after 4 days in vitro. However, in a 12 day in vivo experiment choline acetylase moved toward the periphery at a rate of 0.34 mm/day. After a day or so in vitro the distal accumulations of cholinesterase and glutamic dehydrogenase decreased, with a concomitant and quantitatively equivalent increase in enzyme activities at the proximal end of the nerve. It is postulated that during incubation a mechanism for reversing the direction of flow develops in the peripheral stump of the nerve. Vinblastine inhibited central and peripheral flow of both cholinesterase and glutamic dehydrogenase. Movement of cholinesterase was not affected by ouabain, thalidomide, or phenobarbital, nor by K+ excess (110 mM) or absence.

scholarly journals N-palmitoyl-D-glucosamine, A Natural Monosaccharide-Based Glycolipid, Inhibits TLR4 and Prevents LPS-Induced Inflammation and Neuropathic Pain in Mice

2021 ◽  
Vol 22 (3) ◽  
pp. 1491 ◽  
Author(s):  
Monica Iannotta ◽  
Carmela Belardo ◽  
Maria Consiglia Trotta ◽  
Fabio Arturo Iannotti ◽  
Rosa Maria Vitale ◽  
...  
Keyword(s):  
Sciatic Nerve ◽  
Inflammatory Cytokines ◽  
Lipid A ◽  
Saturated Fatty Acids ◽  
Structural Similarity ◽  
Antagonistic Activity ◽  
Critical Function ◽  
Anti Inflammatory

Toll-like receptors (TLRs) are key receptors through which infectious and non-infectious challenges act with consequent activation of the inflammatory cascade that plays a critical function in various acute and chronic diseases, behaving as amplification and chronicization factors of the inflammatory response. Previous studies have shown that synthetic analogues of lipid A based on glucosamine with few chains of unsaturated and saturated fatty acids, bind MD-2 and inhibit TLR4 receptors. These synthetic compounds showed antagonistic activity against TLR4 activation in vitro by LPS, but little or no activity in vivo. This study aimed to show the potential use of N-palmitoyl-D-glucosamine (PGA), a bacterial molecule with structural similarity to the lipid A component of LPS, which could be useful for preventing LPS-induced tissue damage or even peripheral neuropathies. Molecular docking and molecular dynamics simulations showed that PGA stably binds MD-2 with a MD-2/(PGA)3 stoichiometry. Treatment with PGA resulted in the following effects: (i) it prevented the NF-kB activation in LPS stimulated RAW264.7 cells; (ii) it decreased LPS-induced keratitis and corneal pro-inflammatory cytokines, whilst increasing anti-inflammatory cytokines; (iii) it normalized LPS-induced miR-20a-5p and miR-106a-5p upregulation and increased miR-27a-3p levels in the inflamed corneas; (iv) it decreased allodynia in peripheral neuropathy induced by oxaliplatin or formalin, but not following spared nerve injury of the sciatic nerve (SNI); (v) it prevented the formalin- or oxaliplatin-induced myelino-axonal degeneration of sciatic nerve. SIGNIFICANCE STATEMENT We report that PGA acts as a TLR4 antagonist and this may be the basis of its potent anti-inflammatory activity. Being unique because of its potency and stability, as compared to other similar congeners, PGA can represent a tool for the optimization of new TLR4 modulating drugs directed against the cytokine storm and the chronization of inflammation.

Continuation of fast axonal transport in regenerating axons in vitro

1979 ◽  
Vol 57 (11) ◽  
pp. 1251-1255
Author(s):  
M. A. Bisby ◽  
C. E. Hilton
Keyword(s):  
Sciatic Nerve ◽  
Vagus Nerve ◽  
Axonal Transport ◽  
Nerve Injury ◽  
Axon Regeneration ◽  
Free Medium ◽  
Fast Axonal Transport ◽  
Sensory Axons

A previous study by McLean and co-workers reported that regenerating axons of the rabbit vagus nerve were unable to sustain axonal transport in vitro for several months after nerve injury. In contrast, we found that sensory axons of the rat sciatic nerve were able to transport 3H-labeled protein into their regenerating portions distal to the site of injury within a week after injury when placed in vitro. Transport in vitro was not significantly less than transport in axons maintained in vivo for the same period. Transport occurred in the medium that was used by the McLean group, but was significantly reduced in calcium-free medium. When axon regeneration was delared, only small amounts of activity were present in the nerve distal to the site of injury, showing that labeled protein normally present in that part of the nerve was associated with axons and was not a result of local precursor uptake by nonneural elements in the sciatic nerve. We were not able to explain the failure of McLean and co-workers to demonstrate transport in vitro in regenerating vagus nerve, but we conclude that there is no general peculiarity of growing axons that makes them unable to sustain transport in vitro.

scholarly journals Enzymatic activity in turkey, duck, quail and chicken liver microsomes against four human cytochrome P450 prototype substrates and aflatoxin B1

2011 ◽  
Vol 1 (1) ◽  
pp. 4 ◽  
Author(s):  
Hansen W. Murcia ◽  
Gonzalo J. Díaz ◽  
Sandra Milena Cepeda
Keyword(s):  
Cytochrome P450 ◽  
Aflatoxin B1 ◽  
Enzyme Activities ◽  
High Performance ◽  
Biochemical Characterization ◽  
Liver Microsomes ◽  
Cytochrome P450 Enzymes ◽  
Catalytic Rate

Cytochrome P450 enzymes (CYP) are a group of monooxygenases able to biotransform several kinds of xenobiotics including aflatoxin B1 (AFB1), a highly toxic mycotoxin. These enzymes have been widely studied in humans and others mammals, but there is not enough information in commercial poultry species about their biochemical characteristics or substrate specificity. The aim of the present study was to identify CYPs from avian liver microsomes with the use of prototype substrates specific for human CYP enzymes and AFB1. Biochemical characterization was carried out in vitro and biotransformation products were detected by high-performance liquid chromatography (HPLC). Enzymatic constants were calculated and comparisons between turkey, duck, quail and chicken activities were done. The results demonstrate the presence of four avian ortholog enzyme activities possibly related with a CYP1A1, CYP1A2, CYP2A6 (activity not previously identified) and CYP3A4 poultry orthologs, respectively. Large differences in enzyme kinetics specific for prototype substrates were found among the poultry species studied. Turkey liver microsomes had the highest affinity and catalytic rate for AFB1 whereas chicken enzymes had the lowest affinity and catalytic rate for the same substrate. Quail and duck microsomes showed intermediate values. These results correlate well with the known in vivo sensitivity for AFB1 except for the duck. A high correlation coefficient between 7-ethoxyresorufin-Odeethylase (EROD) and 7-methoxyresorufin- O-deethylase (MROD) activities was found in the four poultry species, suggesting that these two enzymatic activities might be carried out by the same enzyme. The results of the present study indicate that four prototype enzyme activities are present in poultry liver microsomes, possibly related with the presence of three CYP avian orthologs. More studies are needed in order to further characterize these enzymes.

scholarly journals In Vitro and In Silico Antioxidant, Anti-Diabetic, Anti-HIV and Anti-Alzheimer Activity of Endophytic Fungi, Cladosporium uredinicola Phytochemicals

2019 ◽  
Vol 13 ◽  
pp. 13-34
Author(s):  
Melappa Govindappa ◽  
V. Thanuja ◽  
S. Tejashree ◽  
C.A. Soukhya ◽  
Suresh Barge ◽  
...  
Keyword(s):  
Qualitative Method ◽  
Cholinesterase Activity ◽  
Methanol Extract ◽  
High Binding Energy ◽  
Acetyl Cholinesterase ◽  
Gp 120 ◽  
Anti Hiv ◽  
Hiv 1

The present work was aimed to identify phytochemicals in C. uredinicola methanol extract from qualitative, TLC and GC-MS method and evaluated for antioxidant, anti-HIV, anti-diabetes, anti-cholinesterase activity in vitro and in silico. The C. uredinicola extract showed flavonoids, tannins, alkaloids, glycosides, phenols, terpenoids, and coumarins presence in qualitative method. From GC-MS analysis, identified seven different phytochemicals and out of seven, four (coumarin, coumarilic acid, hymecromone, alloisoimperatorin) are coumarins. The C. uredinicola extract have shown significant antioxidant activity in DPPH (73) and FRAP (1359) method. The HIV-1 RT (83.81+2.14), gp 120 (80.24+2.31), integrase (79.43+3.14) and protease (77.63+2.14), DPPIV, β-glucosidase and acetyl cholinesterase activity was significantly reduced by the extract. The 2-diphenylmethyleneamino methyl ester had shown significant interaction with oxidant and HIV-1 proteins whereas alloisoimperatorin have interacted with diabetes and cholinesterase proteins followed by hymecromone with high binding energy. These three phytochemicals are non-carcinogens, non-toxic, readily degradable and have drug likeliness properties. The C. uredinicola phytochemicals are responsible for management of diabetes, HIV-1 and Alzheimer. Further in vivo work is needed to justify our research.

Neurotrophins affect the pattern of DRG neurite growth in a bioassay that presents a choice of CNS and PNS substrates

Development ◽  
1995 ◽  
Vol 121 (5) ◽  
pp. 1301-1309 ◽  
Author(s):  
R. Tuttle ◽  
W.D. Matthew
Keyword(s):  
Spinal Cord ◽  
Central Nervous System ◽  
Nervous System ◽  
Sciatic Nerve ◽  
Sympathetic Neurons ◽  
Neurite Growth ◽  
Drg Neurons ◽  
Substrate Preferences

Neurons can be categorized in terms of where their axons project: within the central nervous system, within the peripheral nervous system, or through both central and peripheral environments. Examples of these categories are cerebellar neurons, sympathetic neurons, and dorsal root ganglion (DRG) neurons, respectively. When explants containing one type of neuron were placed between cryosections of neonatal or adult sciatic nerve and neonatal spinal cord, the neurites exhibited a strong preference for the substrates that they would normally encounter in vivo: cerebellar neurites generally extended only on spinal cord, sympathetic neurites on sciatic nerve, and DRG neurites on both. Neurite growth from DRG neurons has been shown to be stimulated by neurotrophins. To determine whether neurotrophins might also affect the substrate preferences of neurites, DRG were placed between cryosections of neonatal spinal cord and adult sciatic nerve and cultured for 36 to 48 hours in the presence of various neurotrophins. While DRG cultured in NGF-containing media exhibited neurite growth over both spinal cord and sciatic nerve substrates, in the absence of neurotrophins DRG neurites were found almost exclusively on the CNS cryosection. To determine whether these neurotrophin-dependent neurite patterns resulted from the selective survival of subpopulations of DRG neurons with distinct neurite growth characteristics, a type of rescue experiment was performed: DRG cultured in neurotrophin-free medium were fed with NGF-containing medium after 36 hours in vitro and neurite growth examined 24 hours later; most DRG exhibited extensive neurite growth on both peripheral and central nervous system substrates.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of Heparin on Lipolytic Enzyme Activities in vivo and in vitro

Enzyme ◽  
1976 ◽  
Vol 21 (1) ◽  
pp. 21-29 ◽  
Author(s):  
J. Patelski ◽  
Z. Waligora ◽  
A.N. Howard
Keyword(s):  
Enzyme Activities ◽  
Lipolytic Enzyme

scholarly journals Antioxidant and Anti-inflammatory Activities of Cynaroside from Elsholtiza bodinieri

2018 ◽  
Vol 13 (11) ◽  
pp. 1934578X1801301 ◽  
Author(s):  
Ying Zou ◽  
Min Zhang ◽  
Tingrui Zhang ◽  
Junwen Wu ◽  
Jun Wang ◽  
...  
Keyword(s):  
Radical Scavenging ◽  
Reducing Power ◽  
Total Content ◽  
Preparative Hplc ◽  
Dpph Radical ◽  
Anti Inflammatory ◽  
Flavonoid Fraction ◽  
Reducing Power Assay

The flavonoid fraction was obtained from Elsholtiza bodinieri Vaniot (EBV) by ethanol-reflux and liquid-liquid extraction. The total content of flavonoid was 179.55 mg/g, and the purity was 64.6%. Then cynaroside with the purity of 94% was isolated from the fraction by preparative HPLC and characterized by the combined usage of HPLC, ESI-MS, and NMR. The antioxidant activity of cynaroside was determined using 2 complementary methods, namely, 2,2- diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and reducing power assay. The anti-inflammatory effect of cynaroside was investigated based on in-vitro and in-vivo experiment. The results showed that cynaroside from EBV scavenged DPPH radical and reduced Fe3+ to Fe2+ effectively, inhibited NO and ROS production in LPS-stimulated RAW264.7 cells and attenuated the inflammation in the mouse model significantly ( p < 0.01), which showed it to be a nutraceutical product in the food industry.

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