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A wound-inducible tobacco peroxidase gene expresses preferentially in the vascular system.

A tobacco peroxidase gene tpoxN1 was reported to be expressed within 1 h after wounding in leaves [Hiraga et al. (2000a) Plant Cell Physiol. … of known inducers for wound-responsive genes such as jasmonate, 1-aminocyclopropane-1-carboxylate, spermine, phytohormones and other stress treatments did not enhance wound-induced tpoxN1 gene expression in stems at all, but rather repressed it in some cases. Studies using metabolic inhibitors suggested that phosphorylation and dephosphorylation of protei …

Polyamines, and effects from reducing their synthesis during egg development in the yellow fever mosquito, Aedes aegypti.

Development of eggs after a blood meal in the yellow fever mosquito Aedes aegypti involves hormonal changes, synthesis of nucleic acids, act … aining DFMO or MDME partially reversed the effects of these inhibitors. Increases in spermidine and spermine were associated with these reversals.

Inhibition by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) of responses to nitric oxide-donors in rat pulmonary artery: influence of the mechanism of nitric oxide generation.

ODQ, (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, an inhibitor of soluble guanylate cyclase) inhibits vasorelaxant responses to nitric oxid … allel shift in the concentration-relaxation curves to linsidomine (SIN-1), FK409, MAHMA NONOate and spermine NONOate (1.63 to 2.54 log units) with no depression in maximum response; each of these NO donors generates NO in the physiological bathing solution without requiring tissue activation. For the four drugs in this group, the effects of 10 microM ODQ w …

Sodium and ionic strength sensing by the calcium receptor.

The calcium-sensing receptor (CaR) is activated by small changes in extracellular calcium [Ca2+]o) in the physiological range, allowing the … the concentration of external NaCl potently altered the activation of the CaR by external Ca2+ and spermine. Ionic strength had an inverse effect on the sensitivity of CaR to its agonists, with lowering of ionic strength rendering the receptor more sensitive to activation by [Ca2+]o and raising of ionic strength producing the converse effect. Effects of o …

U937 apoptotic cell death by nitric oxide: Bcl-2 downregulation and caspase activation.

Upon treatment with NO-releasing compounds such as S-nitrosoglutathione or spermine NO, human myeloid leukemia U937 cells undergo apoptosis. Early NO-mediated signals comprise activation of a Z-A-DCB (benzoyloxycarbonyl-Asp-CH2OC(O)-2,6-dichlorobenzene)-sensit ive, caspase-3 like cysteine protease that cleaved poly (ADP-ribose) polymerase (PARP), U1 small nuclear ribonucleoprotein (U1 snRNP), and the fluorogenic substrate N-acetyl-Asp-Glu-Val-Asp-7-amido-4-methylcoumarin. In association with these early apoptotic alterations p21 (WAF1/Cip1) is upregulated, but NO affected cell proliferation an…

Nitric oxide enhances hydrogen peroxide-mediated endothelial permeability in vitro.

The objective of this study was to evaluate the effects of nitric oxide (NO) on H2O2-mediated endothelial permeability. H2O2 (0.1 mM) increased permeability at 90 min to 298% of baseline. Spermine NONOate (SNO), an NO donor, at 0.1 or 1 mM did not alter permeability. However, 0.1 mM H2O2 + 1 mM SNO increased permeability to 764%, twice that of 0.1 mM H2O2 alone. These treatments were not directly toxic to endothelial cells. This NO effect was concentration dependent, inasmuch as 0.1 mM SNO did not significantly change H2O2-mediated permeability. The NO-enhanced, H2O2-dependent permeability req…

Acute inhibitory effect of excess iodide on ornithine decarboxylase in the thyroid of propylthiouracil-treated rats.

Polyamines such as putrescine, spermidine and spermine have been thought to play an important role in thyroid growth induced by goitrogens. Reduced biosynthesis of these polyamines might play a role in the antigoitrogenic effects of excess iodide. This study was designed to examine the effect of potassium iodide (KI) on ornithine decarboxylase (ODC), a rate-limiting enzyme in the biosynthesis of polyamines. Thyroidal ODC activity, protein content and mRNA were increased in rats made hypothyroid by 10 days of propylthiouracil treatment. The increase in ODC activity was suppressed after subcutan…

Nitric oxide (NO) in apoptotic versus necrotic RAW 264.7 macrophage cell death: the role of NO-donor exposure, NAD+ content, and p53 accumulation.

Nitric oxide (NO)-releasing compounds cause apoptotic cell death in RAW 264.7 macrophages. This is confirmed morphologically by chromatin co … 6 to 8 h. For intermediate NO releasers like sodium nitroprusside, S-nitrosoglutathione (GSNO), and spermine-NO removal of the NO-donating compound halts fragmentation to a certain degree. The relatively stable diethylenetriamine-nitric oxide complex initiates fragmentation only after prolonged exposure. NO-mediated apoptotic signaling in macrophages neith …

CD45, an integral membrane protein tyrosine phosphatase. Characterization of enzyme activity.

Although CD45 resembles the low Mr protein tyrosine phosphatases (PTPases) from human placenta in its specificity for phosphotyrosyl residue … and maleylated lysozyme as substrate, CD45 was stimulated up to 12-fold by basic compounds such as spermine; divalent metal ions were also stimulatory, most notably Zn2+, which was previously identified as a potent inhibitor of the low Mr PTPases. CD45 was phosphorylated to high stoichiometry by casein kinase-2 (up to 1.5 mol/mol) and also by glycogen syn …

Early polyamine treatment enhances survival of sympathetic neurons after postnatal axonal injury or immunosympathectomy.

We have recently demonstrated that following injury of their axon, sympathetic neurons of the rat superior cervical ganglion become dependen … sive loss of neurons in the ganglion. Daily injections of the polyamines putrescine, spermidine and spermine (10 mg/kg each), for 7 days after the operation to the axotomized group, and for 9 days starting with the first antiserum injection to the immunosympathectomized group, attenuated the nerve cell loss. The polyamine treatment also attenuated the redu …

A method for flow cytometric cell cycle analysis of normal and psoriatic human epidermis based on a detergent/citric acid technique for suspension of nuclei.

A new method is described for flow cytometric cell cycle analysis of normal and psoriatic human epidermis, based on non-enzymatic tissue disaggregation. The epidermis was isolated by treatment with acetic acid and stored by freezing. After thawing, the epidermis was disintegrated into a nuclear suspension by 3 steps: incubation with dithiotreitol, whirling in a buffer (pH 7.4) with the non-ionic detergent Nonidet P40, EGTA, RNase and spermine, and whirling after addition of citric acid to a final concentration of 1% (pH 2.4). The suspension was stained with propidium iodide and filtered before…

Comparative effects of several nitric oxide donors on intracellular cyclic GMP levels in bovine chromaffin cells: correlation with nitric oxide production.

1. Sodium nitroprusside, S-nitroso-N-acetyl-D,L-penicillamine, Spermine NONOate and DEA NONOate raised cyclic GMP levels in bovine chromaffin cells in a time and concentration dependent manner with different potencies, the most potent being DEA/NO with an EC50 value of 0.38 +/- 0.02 microM. 2. Measurements of NO released from these donors revealed that DEA/NO decomposed with a half-life (t1/2) of 3.9 +/- 0.2 min. The t1/2 for SPER/NO was 37 +/- 3 min. SNAP decomposed more slowly (t1/2 = 37 +/- 4 h) and after 60 min the amount of NO produced corresponded to less than 2% of the total SNAP presen…

Characterization and nitric oxide release studies of lipophilic 1-substituted diazen-1-ium-1,2-diolates.

Lipophilic esters of the naturally occurring polyamines putreanine and spermic acid were synthesized, characterized, and modified with nitric oxide to form the corresponding 1-substituted diazen-1-ium-1,2-diolates (previously known as NONOates). The resulting compounds were insoluble in water but were able to release nitric oxide (NO) when placed in phosphate buffered saline (PBS) at physiological pH. The two categories of compounds examined were putreanate esters of cholesterol or hexadecanol, and spermate diesters of cholesterol or hexadecanol. The putreanate NONOate esters of cholesterol an

High-Density Type I Collagen Promotes IFN-γ+ CD8+ T Cell Exhaustion via SAT1-ASS1-Mediated Glutamine Accumulation and Ferroptosis in Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) is an aggressive subtype characterized by poor prognosis because of a lack of effective therapeutic age … ts indicate that high-density type I collagen promotes ferroptosis in TNBC cells through spermidine/spermine N1-acetyltransferase 1 (SAT1)/argininosuccinate synthase (ASS1)-induced glutamine (Gln) accumulation. Moreover, in vitro co-culture and in vivo experiments reveal that high-density type I collagen increases the uptake of Gln in TNBC cells, leading t …

Hierarchically engineered injectable hydrogels loaded with polyphenol for enhanced wound healing and tissue regeneration.

The healing of deep wounds is severely impeded by the converging pathophysiology of persistent inflammation, oxidative stress, bacterial infection, and many other factors that necessitate an ideal solution that simultaneously targets multiple barriers to accelerate the healing of wounds. Here, we report SCLP, a multifunctional, dynamically cross-linked hierarchical hydrogel network synthesised through the strategic integration of a lab-synthesised spermine-gellan gum conjugate (S), chondroitin sulfate (C), LAPONITE®-polyethyleneimine (L-PEI) nanohybrids, and the plant-derived polyphenol protoc…

Polyamines across neurodegenerative proteinopathies.

Polyamines (PAs) are evolutionarily conserved metabolites that connect protein quality control with lysosomal, mitochondrial, and redox home … eling, as a function of neurodegenerative disorders. Mechanistic studies reveal that spermidine and spermine can alter the assembly, condensation, compartmentalization, and clearance of various neurotoxic proteins, whereas the effects of putrescine are more system- and concentration-dependent. These effects engage both shared pathways and distinct mechanis …

Polyamine metabolic enzyme SAT1 remodels the neuronal transcriptome and rescues α-synuclein toxicity in Drosophila.

Polyamine homeostasis is tightly regulated by interconversion and catabolic pathways and has been increasingly implicated in neurodegenerative disorders, including Parkinson's disease (PD), where accumulation of α-synuclein (α-Syn) perturbs neuronal homeostasis. Spermidine/spermine N1-acetyltransferase 1 (SAT1) occupies a central position in polyamine interconversion, and alterations in SAT1 activity have been linked to α-Syn toxicity and PD-related neuropathology. To investigate how SAT1 activity influences α-Syn-associated neurodegeneration, we employed a Drosophila model of neuronal α-Syn e…

Supramolecular Microspheres Fabricated from Macrocycle-Incorporated Polymers and Their Biomedical Applications Based on Host-Guest Recognition.

Microspheres have emerged as a pivotal platform for micron-scale drug delivery, yet their utility has been greatly hindered by limitations i … p) fabricated from the pillar[5]arene (P[5])-incorporated polymer exhibit exceptional efficiency in spermine adsorption, while mineralized supramolecular microspheres (SORA@S-CPMs-p@CaCO3) loaded with sorafeinib (SORA) are successfully employed in embolization therapy, achieving more complete vascular occlusion compared to non-mineralized microspheres. The …

Нацеливание SMOX сохраняет оптический нерв Myelin, аксонская целостность и визуальные функции в мультиклерозе.

Множественный склероз (MS) — хроническое неврологическое состояние, затрагивающее молодых людей. Воспаление, обезвоживание и повреждение аксона являются ключевыми патологическими особенностями MS и его животной модели, экспериментального аутоиммунного энцефаломиелита (EAE). Наша предыдущая работа показала, что ингибирование сперматозоидной оксиды (SMOX) MDL72527, селективный необратимый фармакологический ингибитор, значительно сокращенные клинические симптомы, потеря клеток сетчатки (RGC) и воспаление зрительного нерва в мышах EAE. В настоящем исследовании изучался более широкий терапевтически

Совпадение в аннотации оригинала
Multiple sclerosis (MS) is a highly disabling chronic neurological condition affecting young adults. Inflammation, demyelination, and axonal damage are key pathological features of MS and its animal model, experimental autoimmune encephalomyelitis (EAE). Our previous work demonstrated that inhibiting spermine oxidase (SMOX) with MDL72527, a selective irrever…

MCU Up-regulation contributes to myocardial ischemia-reperfusion Injury through calpain/OPA-1-mediated mitochondrial fusion/mitophagy Inhibition.

Mitochondrial dynamic disorder is involved in myocardial ischemia/reperfusion (I/R) injury. To explore the effect of mitochondrial calcium u … apoptosis, alleviate mitochondrial fission and restore mitochondrial fusion and mitophagy. However, spermine administration, which could enhance MCU function, deteriorated the above-mentioned myocardial cell injury and mitochondrial dynamic imbalanced. In addition, up-regulation of MCU promoted the expression and activation of calpain-1/2 and down-regulate …