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1.
Cells ; 10(8)2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34440845

RESUMO

Keratoconus (KC) is a common corneal ectatic disease that affects 1:500-1:2000 people worldwide and is associated with a progressive thinning of the corneal stroma that may lead to severe astigmatism and visual deficits. Riboflavin-mediated collagen crosslinking currently remains the only approved treatment to halt progressive corneal thinning associated with KC by improving the biomechanical properties of the stroma. Treatments designed to increase collagen deposition by resident corneal stromal keratocytes remain elusive. In this study, we evaluated the effects of arginine supplementation on steady-state levels of arginine and arginine-related metabolites (e.g., ornithine, proline, hydroxyproline, spermidine, and putrescine) and collagen protein expression by primary human corneal fibroblasts isolated from KC and non-KC (healthy) corneas and cultured in an established 3D in vitro model. We identified lower cytoplasmic arginine and spermidine levels in KC-derived constructs compared to healthy controls, which corresponded with overall higher gene expression of arginase. Arginine supplementation led to a robust increase in cytoplasmic arginine, ornithine, and spermidine levels in controls only and a significant increase in collagen type I secretion in KC-derived constructs. Further studies evaluating safety and efficacy of arginine supplementation are required to elucidate the potential therapeutic applications of modulating collagen deposition in the context of KC.


Assuntos
Arginina/farmacologia , Matriz Extracelular/metabolismo , Ceratocone/patologia , Regulação para Cima/efeitos dos fármacos , Arginase/metabolismo , Arginina/metabolismo , Arginina/uso terapêutico , Estudos de Casos e Controles , Técnicas de Cultura de Células , Células Cultivadas , Colágeno/metabolismo , Colágeno Tipo I/metabolismo , Córnea/citologia , Córnea/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Ceratocone/tratamento farmacológico , Ceratocone/metabolismo , Óxido Nítrico Sintase/metabolismo , Ornitina/metabolismo , Espermidina/metabolismo
2.
Cells ; 10(8)2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34440637

RESUMO

Post orgasmic illness syndrome is a rare, mysterious condition with an unknown pathomechanism and uncertain treatment. The symptoms of post orgasmic illness syndrome last about 2-7 days after an ejaculation. The current hypothesis proposes that the primary injury in post orgasmic illness syndrome is an acute compression proprioceptive axonopathy in the muscle spindle, as is suspected in delayed onset muscle soreness. The terminal arbor degeneration-like lesion of delayed onset muscle soreness is theorized to be an acute stress response energy-depleted dysfunctional mitochondria-induced impairment of Piezo2 channels and glutamate vesicular release. The recurring symptoms of post orgasmic illness syndrome after each ejaculation are suggested to be analogous to the repeated bout effect of delayed onset muscle soreness. However, there are differences in the pathomechanism, mostly attributed to the extent of secondary tissue damage and to the extent of spermidine depletion. The spermidine depletion-induced differences are as follows: modulation of the acute stress response, flu-like symptoms, opioid-like withdrawal and enhanced deregulation of the autonomic nervous system. The longitudinal dimension of delayed onset muscle soreness, in the form of post orgasmic illness syndrome and the repeated bout effect, have cognitive and memory consequences, since the primary injury is learning and memory-related.


Assuntos
Ejaculação , Canais Iônicos/metabolismo , Fusos Musculares/inervação , Músculo Esquelético/inervação , Mialgia/etiologia , Orgasmo , Doenças do Sistema Nervoso Periférico/etiologia , Propriocepção , Animais , Humanos , Masculino , Contração Muscular , Fusos Musculares/metabolismo , Mialgia/metabolismo , Mialgia/fisiopatologia , Doenças do Sistema Nervoso Periférico/metabolismo , Doenças do Sistema Nervoso Periférico/fisiopatologia , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores Opioides/metabolismo , Espermidina/metabolismo , Estresse Fisiológico , Síndrome , Fatores de Tempo
3.
DNA Cell Biol ; 40(9): 1144-1157, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34165351

RESUMO

Polyamines (PAs), especially spermidine and spermine (which are involved in various types of abiotic stress tolerance), have been reported in many plant species. In this study, we identified 14 putative S-adenosylmethionine decarboxylase genes (GhSAMDC1-14) in upland cotton. Based on phylogenetic and expression analyses conducted under different abiotic stresses, we selected and transferred GhSAMDC3 into Arabidopsis thaliana. Compared to the wild type, transgenic plants displayed rapid growth and increases in average leaf area and leaf number of 52% and 36%, respectively. In transgenic plants, the germination vigor and rate were markedly enhanced under NaCl treatment, and the plant survival rate increased by 50% under 300 mM NaCl treatment. The spermidine content was significantly increased, possibly due to the synthesis of a series of PAs and oxidant and antioxidant genes, resulting in improved salinity tolerance in Arabidopsis. Various salinity resistance-related genes were upregulated in transgenic plants. Together, these results indicate that ectopic expression of GhSAMDC3 raised salinity tolerance by the accumulation of spermidine and activation of salinity tolerance-related genes in A. thaliana.


Assuntos
Adenosilmetionina Descarboxilase/genética , Proteínas de Arabidopsis/genética , Arabidopsis , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas , Tolerância ao Sal/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Expressão Ectópica do Gene , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Espermidina/metabolismo , Espermina/metabolismo
4.
Theriogenology ; 168: 25-32, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33845261

RESUMO

Given that spermidine is associated with aging-related diseases and it is a potential target for delaying aging, functional studies on supraphysiological levels of spermidine are required. Our previous studies showed that the granulosa layer arranged irregular and the follicular oocytes were shrunk in female mice injected intraperitoneally with spermidine at 150 mg/kg (Body weight) after 24 h. It indicated that supraphysiological levels of spermidine induced ovarian damage in female mice. The objective of this study was to investigate the effect of acute administration of supraphysiological spermidine on the ovary and granulosa cells in mice. The results showed that treatment with spermidine at 150 mg/kg (intraperitoneal) significantly increased the levels of both H2O2 and malondialdehyde and reduced total antioxidant capacity and the activities of catalase and superoxide dismutase in mouse ovaries. The contents of putrescine and spermine increased significantly in the ovaries of mice treated with spermidine. Treatment with spermidine at 150 mg/kg increased the apoptotic rate and reactive oxygen species levels of granulosa cells in mouse ovaries. Furthermore, the protein expression of P53, CASPASE 8 (Cleaved/Pro), CASPASE 9 (Cleaved/Pro) and CASPASE 3 (Cleaved/Pro) in granulosa cells of mice treated with spermidine were significantly upregulated, while BCL2 expression was significantly downregulated. In summary, our study demonstrates for the first time that spermidine at supraphysiological doses causes ovarian oxidative stress and induces granulosa cell apoptosis via the P53 and/or BCL2-CASPASEs pathway.


Assuntos
Ovário , Espermidina , Animais , Apoptose , Feminino , Células da Granulosa/metabolismo , Peróxido de Hidrogênio/metabolismo , Camundongos , Ovário/metabolismo , Estresse Oxidativo , Espermidina/metabolismo
5.
J Bacteriol ; 203(10)2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33685971

RESUMO

Polyamines are essential for biofilm formation in Escherichia coli, but it is still unclear which polyamines are primarily responsible for this phenomenon. To address this issue, we constructed a series of E. coli K-12 strains with mutations in genes required for the synthesis and metabolism of polyamines. Disruption of the spermidine synthase gene (speE) caused a severe defect in biofilm formation. This defect was rescued by the addition of spermidine to the medium but not by putrescine or cadaverine. A multidrug/spermidine efflux pump membrane subunit (MdtJ)-deficient strain was anticipated to accumulate more spermidine and result in enhanced biofilm formation compared to the MdtJ+ strain. However, the mdtJ mutation did not affect intracellular spermidine or biofilm concentrations. E. coli has the spermidine acetyltransferase (SpeG) and glutathionylspermidine synthetase/amidase (Gss) to metabolize intracellular spermidine. Under biofilm-forming conditions, not Gss but SpeG plays a major role in decreasing the too-high intracellular spermidine concentrations. Additionally, PotFGHI can function as a compensatory importer of spermidine when PotABCD is absent under biofilm-forming conditions. Last, we report here that, in addition to intracellular spermidine, the periplasmic binding protein (PotD) of the spermidine preferential ABC transporter is essential for stimulating biofilm formation.IMPORTANCE Previous reports have speculated on the effect of polyamines on bacterial biofilm formation. However, the regulation of biofilm formation by polyamines in Escherichia coli has not yet been assessed. The identification of polyamines that stimulate biofilm formation is important for developing novel therapies for biofilm-forming pathogens. This study sheds light on biofilm regulation in E. coli Our findings provide conclusive evidence that only spermidine can stimulate biofilm formation in E. coli cells, not putrescine or cadaverine. Last, ΔpotD inhibits biofilm formation even though the spermidine is synthesized inside the cells from putrescine. Since PotD is significant for biofilm formation and there is no ortholog of the PotABCD transporter in humans, PotD could be a target for the development of biofilm inhibitors.


Assuntos
Biofilmes/crescimento & desenvolvimento , Escherichia coli K12/fisiologia , Proteínas de Escherichia coli/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas Periplásmicas de Ligação/metabolismo , Espermidina/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Acetiltransferases/metabolismo , Amida Sintases/metabolismo , Cadaverina/farmacologia , Meios de Cultura , Escherichia coli K12/efeitos dos fármacos , Escherichia coli K12/genética , Proteínas de Escherichia coli/genética , Deleção de Genes , Proteínas de Membrana Transportadoras/genética , Mutação , Óperon , Proteínas Periplásmicas de Ligação/genética , Putrescina/farmacologia , Espermidina/farmacologia , Espermidina Sintase/genética , Espermidina Sintase/metabolismo
6.
Aging (Albany NY) ; 13(5): 6375-6405, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33653967

RESUMO

The presence of Akkermansia muciniphila (Akk) in the human gut is associated with good health, leanness and fitness. Mouse experimentation has demonstrated positive effects for Akk, which counteracts aging, mediates antiobesity and antidiabetic effects, dampens inflammation and improves anticancer immunosurveillance. Clinical trials have confirmed antidiabetic effects for Akk. Here, we investigated the time-dependent effects of oral administration of Akk (which was live or pasteurized) and other bacteria to mice on the metabolome of the ileum, colon, liver and blood plasma. Metabolomics was performed by a combination of chromatographic and mass spectrometric methods, yielding a total of 1.637.227 measurements. Akk had major effects on metabolism, causing an increase in spermidine and other polyamines in the gut and in the liver. Pasteurized Akk (Akk-past) was more efficient than live Akk in elevating the intestinal concentrations of polyamines, short-chain fatty acids, 2-hydroxybutyrate, as well multiple bile acids, which also increased in the circulation. All these metabolites have previously been associated with human health, providing a biochemical basis for the beneficial effects of Akk.


Assuntos
Probióticos/farmacologia , Administração Oral , Akkermansia , Animais , Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal , Trato Gastrointestinal/metabolismo , Hidroxibutiratos/metabolismo , Fígado/metabolismo , Metaboloma , Metabolômica , Camundongos Endogâmicos C57BL , Pasteurização , Poliaminas/metabolismo , Espermidina/metabolismo
7.
Int J Mol Sci ; 22(3)2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33572992

RESUMO

Retinal pigment epithelial (RPE) cells occupy the outer layer of the retina and perform various biological functions. Oxidative damage to RPE cells is a major risk factor for retinal degeneration that ultimately leads to vision loss. In this study, we investigated the role of spermidine in a hydrogen peroxide (H2O2)-induced oxidative stress model using human RPE cells. Our findings showed that 300 µM H2O2 increased cytotoxicity, apoptosis, and cell cycle arrest in the G2/M phase, whereas these effects were markedly suppressed by 10 µM spermidine. Furthermore, spermidine significantly reduced H2O2-induced mitochondrial dysfunction including mitochondrial membrane potential and mitochondrial activity. Although spermidine displays antioxidant properties, the generation of intracellular reactive oxygen species (ROS) upon H2O2 insult was not regulated by spermidine. Spermidine did suppress the increase in cytosolic Ca2+ levels resulting from endoplasmic reticulum stress in H2O2-stimulated human RPE cells. Treatment with a cytosolic Ca2+ chelator markedly reversed H2O2-induced cellular dysfunction. Overall, spermidine protected against H2O2-induced cellular damage by blocking the increase of intracellular Ca2+ independently of ROS. These results suggest that spermidine protects RPE cells from oxidative stress, which could be a useful treatment for retinal diseases.


Assuntos
Apoptose , Cálcio/metabolismo , Estresse Oxidativo , Epitélio Pigmentado da Retina/citologia , Espermidina/metabolismo , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Humanos , Peróxido de Hidrogênio/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/metabolismo , Espermidina/farmacologia
8.
Commun Biol ; 4(1): 231, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608630

RESUMO

An unbalanced microbial ecosystem on the human skin is closely related to skin diseases and has been associated with inflammation and immune responses. However, little is known about the role of the skin microbiome on skin aging. Here, we report that the Streptococcus species improved the skin structure and barrier function, thereby contributing to anti-aging. Metagenomic analyses showed the abundance of Streptococcus in younger individuals or those having more elastic skin. Particularly, we isolated Streptococcus pneumoniae, Streptococcus infantis, and Streptococcus thermophilus from face of young individuals. Treatment with secretions of S. pneumoniae and S. infantis induced the expression of genes associated with the formation of skin structure and the skin barrier function in human skin cells. The application of culture supernatant including Streptococcal secretions on human skin showed marked improvements on skin phenotypes such as elasticity, hydration, and desquamation. Gene Ontology analysis revealed overlaps in spermidine biosynthetic and glycogen biosynthetic processes. Streptococcus-secreted spermidine contributed to the recovery of skin structure and barrier function through the upregulation of collagen and lipid synthesis in aged cells. Overall, our data suggest the role of skin microbiome into anti-aging and clinical applications.


Assuntos
Microbiota , Envelhecimento da Pele , Pele/microbiologia , Espermidina/metabolismo , Streptococcus/metabolismo , Adulto , Colágeno/metabolismo , Disbiose , Elasticidade , Feminino , Humanos , Lipogênese , Metagenoma , Fenótipo , Pele/metabolismo , Streptococcus/genética , Streptococcus/crescimento & desenvolvimento , Adulto Jovem
9.
Life Sci ; 265: 118739, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33186567

RESUMO

AIMS: The therapeutic effects of spermidine on preexisting obese mice have been not fully elucidated. In this study, we assessed the anti-obesity impact of spermidine on high-fat diet (HFD)-induced obese mice. MAIN METHODS: C57BL/6J mice were fed a HFD for 16 weeks to induce obesity, and then treated with or without spermidine via drinking water for additional 8 weeks. The contributions of spermidine in regulating obesity phenotypes and metabolic syndrome were further evaluated. KEY FINDINGS: Spermidine administration lowered fat mass and plasma lipid profile in HFD-induced obese mice without affecting body weight. In addition, spermidine attenuated hepatic steatosis by regulating lipid metabolism and enhancing antioxidant capacity. Moreover, spermidine reduced adipose tissue inflammation by decreasing inflammatory cytokine and chemokines expression, and these results might contributed to the enhanced thermogenic gene expression in brown adipose tissue. Furthermore, spermidine treatment enhanced gut barrier function by up-regulating tight junction- and mucin-related gene expression. SIGNIFICANCE: Spermidine-mediated protective impacts involve the regulation of lipid metabolism, inflammation response, gut barrier function and thermogenesis. These findings demonstrate that spermidine has potentials in treating obesity.


Assuntos
Fígado Gorduroso/fisiopatologia , Espermidina/farmacologia , Tecido Adiposo/metabolismo , Tecido Adiposo Marrom/metabolismo , Animais , Fármacos Antiobesidade/farmacologia , Dieta Hiperlipídica/efeitos adversos , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/metabolismo , Inflamação/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/metabolismo , Espermidina/metabolismo , Termogênese/efeitos dos fármacos
10.
J Alzheimers Dis ; 79(2): 895-903, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33361604

RESUMO

BACKGROUND: Cerebral amyloid angiopathy (CAA) is one of the major causes of intracerebral hemorrhage and vascular dementia in older adults. Early diagnosis will provide clinicians with an opportunity to intervene early with suitable strategies, highlighting the importance of pre-symptomatic CAA biomarkers. OBJECTIVE: Investigation of pre-symptomatic CAA related blood metabolite alterations in Dutch-type hereditary CAA mutation carriers (D-CAA MCs). METHODS: Plasma metabolites were measured using mass-spectrometry (AbsoluteIDQ® p400 HR kit) and were compared between pre-symptomatic D-CAA MCs (n = 9) and non-carriers (D-CAA NCs, n = 8) from the same pedigree. Metabolites that survived correction for multiple comparisons were further compared between D-CAA MCs and additional control groups (cognitively unimpaired adults). RESULTS: 275 metabolites were measured in the plasma, 22 of which were observed to be significantly lower in theD-CAAMCs compared to D-CAA NCs, following adjustment for potential confounding factors age, sex, and APOE ε4 (p < 00.05). After adjusting for multiple comparisons, only spermidine remained significantly lower in theD-CAAMCscompared to theD-CAA NCs (p  < 0.00018). Plasma spermidine was also significantly lower in D-CAA MCs compared to the cognitively unimpaired young adult and older adult groups (p < 0.01). Spermidinewas also observed to correlate with CSF Aß40 (rs = 0.621, p = 0.024), CSF Aß42 (rs = 0.714, p = 0.006), and brain Aß load (rs = -0.527, p = 0.030). CONCLUSION: The current study provides pilot data on D-CAA linked metabolite signals, that also associated with Aß neuropathology and are involved in several biological pathways that have previously been linked to neurodegeneration and dementia.


Assuntos
Angiopatia Amiloide Cerebral Familiar/sangue , Adulto , Doenças Assintomáticas , Biomarcadores/sangue , Estudos de Casos e Controles , Angiopatia Amiloide Cerebral Familiar/genética , Angiopatia Amiloide Cerebral Familiar/metabolismo , Feminino , Heterozigoto , Humanos , Masculino , Espectrometria de Massas , Testes de Estado Mental e Demência , Metabolômica , Neuroimagem , Linhagem , Placa Amiloide/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Espermidina/sangue , Espermidina/metabolismo
11.
Ecotoxicol Environ Saf ; 207: 111265, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920313

RESUMO

Aluminum (Al) toxicity is a major yield-limiting factor for crops in acidic soils. In this work, we have investigated the potential role of spermidine (Spd) on Al toxicity in rice chloroplasts. Exogenous Spd markedly reduced Al concentration and elevated other nutrient elements such as Mn, Mg, Fe, K, Ca, and Mo in chloroplasts of Al-treated plants. Meanwhile, Spd further activated arginine decarboxylase (ADC) activity of key enzyme in polyamine (PA) synthesis, and enhanced PA contents in chloroplasts. Spd application dramatically addressed Al-induced chlorophyll (Chl) losses, inhibited thylakoid membrane protein complexes degradation, especially photosystem II (PSII), and significantly depressed the accumulations of superoxide radical (O2·-), hydrogen peroxide (H2O2), and malondialdehyde (MDA) in chloroplasts. Spd addition activated antioxidant enzyme activities and decreased soluble sugar content in chloroplasts compared with Al treatment alone. Spd not only reversed the inhibition of photosynthesis-related gene transcript levels induced by Al toxicity, but diminished the increased expression of Chl catabolism-related genes. Furthermore, Chl fluorescence analysis showed that Spd protected PSII reaction centers and photosynthetic electron transport chain under Al stress, thus improving photosynthetic performance. These results suggest that PAs are involved in Al tolerance in rice chloroplasts and can effectively protect the integrity and function of photosynthetic apparatus, especially PSII, by mitigating oxidative damage induced by Al toxicity.


Assuntos
Alumínio/toxicidade , Complexo de Proteína do Fotossistema II/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Espermidina/farmacologia , Alumínio/metabolismo , Antioxidantes/metabolismo , Clorofila/metabolismo , Cloroplastos/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Fotossíntese/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/metabolismo , Poliaminas/metabolismo , Espermidina/metabolismo
12.
Biomolecules ; 10(12)2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33271940

RESUMO

Toll-like receptors (TLRs) are transmembrane proteins that are key regulators of innate and adaptive immune responses, particularly TLR4, and they have been identified as potential drug targets for the treatment of disease. Several low-molecular-weight compounds are being considered as new drug targets for various applications, including as immune modulators. Mygalin, a 417 Da synthetic bis-acylpolyamine, is an analog of spermidine that has microbicidal activity. In this study, we investigated the effect of mygalin on the innate immune response based on a virtual screening (VS) and molecular docking analysis. Bone marrow-derived macrophages and the cell lines J774A.1 and RAW 264.7 stimulated with lipopolysaccharide (LPS) were used to confirm the data obtained in silico. Virtual screening and molecular docking suggested that mygalin binds to TLR4 via the protein myeloid differentiation factor 2 (MD-2) and LPS. Macrophages stimulated by mygalin plus LPS showed suppressed gene expression of tumor necrosis factor (TNF-α), interleukine 6 (IL-6), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), as well as inhibition of signaling protein p65 of the nuclear factor κB (NF-κB), resulting in decreased production of nitric oxide (NO) and TNF-α. These results indicate that mygalin has anti-inflammatory potential, being an attractive option to be explored. In addition, we reinforce the importance of virtual screening analysis to assist in the discovery of new drugs.


Assuntos
Simulação de Acoplamento Molecular , Espermidina/análogos & derivados , Receptor 4 Toll-Like/metabolismo , Animais , Imunidade Inata/efeitos dos fármacos , Camundongos , Conformação Proteica , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Espermidina/metabolismo , Espermidina/farmacologia , Receptor 4 Toll-Like/química
13.
Free Radic Biol Med ; 161: 339-350, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33122005

RESUMO

Distinct metabolic programs, either energy-consuming anabolism or energy-generating catabolism, were required for different biological functions. Macrophages can adopt different immune phenotypes in response to various cues and exhibit anti- or pro-inflammatory properties relying on catabolic pathways associated with oxidative phosphorylation (OXPHOS) or glycolysis. Spermidine, a natural polyamine, has been reported to regulate inflammation through inducing anti-inflammatory (M2) macrophages. However, the underlying mechanisms remain elusive. We show here that the M2-polarization induced by spermidine is mediated by mitochondrial reactive oxygen species (mtROS). The levels of mitochondrial superoxide and H2O2 were markedly elevated by spermidine. Mechanistically, mtROS were found to activate AMP-activated protein kinase (AMPK), which in turn enhanced mitochondrial function. Furthermore, hypoxia-inducible factor-1α (Hif-1α) was upregulated by the AMPK activation and mtROS and was required for the expression of anti-inflammatory genes and induction of autophagy. Consistent with previous report that autophagy is required for the M2 polarization, we found that the M2 polarization induced by spermidine was also mediated by increased autophagy. The macrophages treated with spermidine in vitro were found to ameliorate Dextran Sulfate Sodium (DSS)-induced inflammatory bowel disease (IBD) in mice. Thus, spermidine can elicit an anti-inflammatory program driven by mtROS-dependent AMPK activation, Hif-1α stabilization and autophagy induction in macrophages. Our studies revealed a critical role of mtROS in shaping macrophages into M2-like phenotype and provided novel information for management of inflammatory disease by spermidine.


Assuntos
Proteínas Quinases Ativadas por AMP , Espermidina , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Autofagia , Peróxido de Hidrogênio/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Macrófagos/metabolismo , Camundongos , Mitocôndrias/metabolismo , Espermidina/metabolismo , Espermidina/farmacologia , Superóxidos/metabolismo , Regulação para Cima
14.
Vet Microbiol ; 250: 108839, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33002680

RESUMO

Like obligate intracellular parasites, viruses co-opt host cell resources to establish productive infections. Polyamines are key aliphatic molecules that perform important roles in cellular growth and proliferation. They are also needed for the successful multiplication of various viruses. Little is known about the effects of polyamines on Arteriviridae infections. Here, porcine reproductive and respiratory syndrome virus (PRRSV), an economically prominent porcine virus, was used to investigate virus-polyamine interactions. We found that PRRSV infection significantly downregulated the levels of cellular polyamines. Using an inhibitor or specific short interfering RNAs (siRNAs) of ornithine decarboxylase 1, a key anabolic enzyme involved in the classical de novo biosynthesis of polyamines, we found that polyamine depletion abrogated PRRSV proliferation, and this effect was recoverable by adding exogenous spermidine and spermine, but not putrescine to the cells, suggesting that the host inhibits polyamine biosynthesis to restrict PRRSV proliferation. Further analysis revealed that the expression level of spermidine-spermine acetyltransferase 1 (SAT1), a catabolic enzyme that reduces spermidine and spermine levels, was upregulated during PRRSV infection, but conversely, SAT1 had an inhibitory effect on PRRSV reproduction. Our data show that polyamines are important molecules during PRRSV-host interactions, and polyamines and their biosynthetic pathways are potential therapeutic targets against PRRSV infection.


Assuntos
Acetiltransferases/genética , Interações entre Hospedeiro e Microrganismos , Poliaminas/metabolismo , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Espermidina/metabolismo , Espermina/metabolismo , Acetiltransferases/metabolismo , Animais , Linhagem Celular , Regulação para Baixo , Regulação da Expressão Gênica , Rim/citologia , Suínos , Regulação para Cima , Replicação Viral
15.
Elife ; 92020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32960172

RESUMO

Exploring the complexity of host-pathogen communication is vital to understand why microbes persist within a host, while others are cleared. Here, we employed a dual-sequencing approach to unravel conversational turn-taking of dynamic host-pathogen communications. We demonstrate that upon hitting a host cell, motile Pseudomonas aeruginosa induce a specific gene expression program. This results in the expression of spermidine on the surface, which specifically activates the PIP3-pathway to induce phagocytic uptake into primary or immortalized murine cells. Non-motile bacteria are more immunogenic due to a lower expression of arnT upon host-cell contact, but do not produce spermidine and are phagocytosed less. We demonstrate that not only the presence of pathogen inherent molecular patterns induces immune responses, but that bacterial motility is linked to a host-cell-induced expression of additional immune modulators. Our results emphasize on the value of integrating microbiological and immunological findings to unravel complex and dynamic host-pathogen interactions.


Assuntos
Interações Hospedeiro-Patógeno , Fagocitose , Pseudomonas aeruginosa/metabolismo , Espermidina/metabolismo , Animais , Transporte Biológico , Camundongos , Células RAW 264.7
16.
Amino Acids ; 52(8): 1169-1180, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32816168

RESUMO

Polyamines (PAs), such as spermidine (SPD) and spermine (SPM), are essential to promote cell growth, survival, proliferation, and longevity. In the adult central nervous system (CNS), SPD and SPM are accumulated predominantly in healthy adult glial cells where PA synthesis is not present. To date, the accumulation and biosynthesis of PAs in developing astrocytes are not well understood. The purpose of the present study was to determine the contribution of uptake and/or synthesis of PAs using proliferation of neonatal astrocytes as an endpoint. We inhibited synthesis of PAs using α-difluoromethylornithine (DFMO; an inhibitor of the PA biosynthetic enzyme ornithine decarboxylase (ODC)) and inhibited uptake of PAs using trimer44NMe (PTI; a novel polyamine transport inhibitor). DFMO, but not PTI alone, blocked proliferation, suggesting that PA biosynthesis was present. Furthermore, exogenous administration of SPD rescued cell proliferation when PA synthesis was blocked by DFMO. When both synthesis and uptake of PAs were inhibited (DFMO + PTI), exogenous SPD no longer supported proliferation. These data indicate that neonatal astrocytes synthesize sufficient quantities of PAs de novo to support cell proliferation, but are also able to import exogenous PAs. This suggests that the PA uptake mechanism is present in both neonates as well as in adults and can support cell proliferation in neonatal astrocytes when ODC is blocked.


Assuntos
Astrócitos/metabolismo , Poliaminas/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Eflornitina , Poliaminas/antagonistas & inibidores , Transporte Proteico , Ratos , Ratos Sprague-Dawley , Espermidina/metabolismo , Espermina/metabolismo
17.
Int J Mol Sci ; 21(15)2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32752130

RESUMO

The eukaryotic and archaeal translation factor IF5A requires a post-translational hypusine modification, which is catalyzed by deoxyhypusine synthase (DHS) at a single lysine residue of IF5A with NAD+ and spermidine as cofactors, followed by hydroxylation to form hypusine. While human DHS catalyzed reactions have been well characterized, the mechanism of the hypusination of archaeal IF5A by DHS is not clear. Here we report a DHS structure from Pyrococcus horikoshii OT3 (PhoDHS) at 2.2 Å resolution. The structure reveals two states in a single functional unit (tetramer): two NAD+-bound monomers with the NAD+ and spermidine binding sites observed in multi-conformations (closed and open), and two NAD+-free monomers. The dynamic loop region V288-P299, in the vicinity of the active site, adopts different positions in the closed and open conformations and is disordered when NAD+ is absent. Combined with NAD+ binding analysis, it is clear that PhoDHS can exist in three states: apo, PhoDHS-2 equiv NAD+, and PhoDHS-4 equiv NAD+, which are affected by the NAD+ concentration. Our results demonstrate the dynamic structure of PhoDHS at the NAD+ and spermidine binding site, with conformational changes that may be the response to the local NAD+ concentration, and thus fine-tune the regulation of the translation process via the hypusine modification of IF5A.


Assuntos
Oxirredutases atuantes sobre Doadores de Grupo CH-NH/ultraestrutura , Fatores de Iniciação de Peptídeos/ultraestrutura , Processamento de Proteína Pós-Traducional/genética , Pyrococcus horikoshii/ultraestrutura , Sítios de Ligação/genética , Cristalografia por Raios X , Eucariotos/genética , Eucariotos/metabolismo , Lisina/análogos & derivados , Lisina/química , Lisina/genética , Lisina/metabolismo , NAD/química , NAD/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/química , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Fatores de Iniciação de Peptídeos/química , Fatores de Iniciação de Peptídeos/genética , Conformação Proteica , Pyrococcus horikoshii/enzimologia , Espermidina/química , Espermidina/metabolismo
18.
Anal Biochem ; 607: 113831, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32739346

RESUMO

We developed a new procedure for the comprehensive analysis of metabolites and enzymes involved in polyamine metabolism pathways. The procedure utilizes stable isotope-labeled polyamines and directly and precisely determines labeled products from enzymatic reactions by ESI-Q-TOF-MS. The activity of different enzymes could be determined in essentially the same manner by suitably adjusting the reaction conditions for each individual enzyme. We applied the procedure to extracts of regenerating rat liver and analyzed the changes in polyamine-metabolizing enzymes and polyamine contents during recovery from partial hepatectomy. A general outline of polyamine metabolism and information of polyamine dynamics were obtained. This kind of comprehensive information would be valuable in unifying detailed but fragmentary information obtained through conventional analyses focusing on one or a few enzymes and on a limited aspect of polyamine metabolic pathway.


Assuntos
Enzimas/metabolismo , Poliaminas/análise , Poliaminas/metabolismo , Animais , Isótopos de Carbono/química , Ativação Enzimática , Marcação por Isótopo , Fígado/metabolismo , Masculino , Metionina/química , Ratos , Espectrometria de Massas por Ionização por Electrospray , Espermidina/química , Espermidina/metabolismo , Espermina/química , Espermina/metabolismo
19.
ChemMedChem ; 15(24): 2420-2435, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-32805075

RESUMO

Leishmania and Trypanosoma parasites are responsible for the challenging neglected tropical diseases leishmaniases, Chagas disease, and human African trypanosomiasis, which account for up to 40,000 deaths annually mainly in developing countries. Current chemotherapy relies on drugs with significant limitations in efficacy and safety, prompting the urgent need to explore innovative approaches to improve the drug discovery pipeline. The unique trypanothione-based redox pathway, which is absent in human hosts, is vital for all trypanosomatids and offers valuable opportunities to guide the rational development of specific, broad-spectrum and innovative anti-trypanosomatid agents. Major efforts focused on the key metabolic enzymes trypanothione synthetase-amidase and trypanothione reductase, whose inhibition should affect the entire pathway and, finally, parasite survival. Herein, we will report and comment on the most recent studies in the search for enzyme inhibitors, underlining the promising opportunities that have emerged so far to drive the exploration of future successful therapeutic approaches.


Assuntos
Inibidores Enzimáticos/farmacologia , Glutationa/análogos & derivados , Espermidina/análogos & derivados , Tripanossomicidas/farmacologia , Amida Sintases/antagonistas & inibidores , Amidoidrolases/antagonistas & inibidores , Animais , Doença de Chagas/tratamento farmacológico , Inibidores Enzimáticos/química , Inibidores Enzimáticos/uso terapêutico , Glutationa/metabolismo , Humanos , Leishmania/efeitos dos fármacos , Leishmania/enzimologia , Leishmaniose/tratamento farmacológico , NADH NADPH Oxirredutases/antagonistas & inibidores , Proteínas de Protozoários/antagonistas & inibidores , Espermidina/metabolismo , Tripanossomicidas/química , Tripanossomicidas/uso terapêutico , Trypanosoma/efeitos dos fármacos , Trypanosoma/enzimologia
20.
Kidney Int ; 98(6): 1434-1448, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32603735

RESUMO

Podocyte maintenance and stress resistance are exquisitely based on high basal rates of autophagy making these cells a unique model to unravel mechanisms of autophagy regulation. Polyamines have key cellular functions such as proliferation, nucleic acid biosynthesis and autophagy. Here we test whether endogenous spermidine signaling is a driver of basal and dynamic autophagy in podocytes by using genetic and pharmacologic approaches to interfere with different steps of polyamine metabolism. Translational studies revealed altered spermidine signaling in focal segmental glomerulosclerosis in vivo and in vitro. Exogenous spermidine supplementation emerged as new treatment strategy by successfully activating autophagy in vivo via inhibition of EP300, a protein with an essential role in controlling cell growth, cell division and prompting cells to differentiate to take on specialized functions. Surprisingly, gas chromatography-mass spectroscopy based untargeted metabolomics of wild type and autophagy deficient primary podocytes revealed a positive feedback mechanism whereby autophagy itself maintains polyamine metabolism and spermidine synthesis. The transcription factor MAFB acted as an upstream regulator of polyamine metabolism. Thus, our data highlight a novel positive feedback loop of autophagy and spermidine signaling allowing maintenance of high basal levels of autophagy as a key mechanism to sustain the filtration barrier. Hence, spermidine supplementation may emerge as a new therapeutic to restore autophagy in glomerular disease.


Assuntos
Glomerulosclerose Segmentar e Focal , Podócitos , Espermidina , Autofagia , Proliferação de Células , Humanos , Espermidina/metabolismo
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