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1.
Planta ; 254(5): 108, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34694486

RESUMO

MAIN CONCLUSION: Identification of the polyamine biosynthetic pathway genes in duckweed S. polyrhiza reveals presence of prokaryotic as well as land plant-type ADC pathway but absence of ODC encoding genes. Their differential gene expression and transcript abundance is shown modulated by exogenous methyl jasmonate, salinity, and acidic pH. Genetic components encoding for polyamine (PA) biosynthetic pathway are known in several land plant species; however, little is known about them in aquatic plants. We utilized recently sequenced three duckweed (Spirodela polyrhiza) genome assemblies to map PA biosynthetic pathway genes in S. polyrhiza. PA biosynthesis in most higher plants except for Arabidopsis involves two pathways, via arginine decarboxylase (ADC) and ornithine decarboxylase (ODC). ADC-mediated PA biosynthetic pathway genes, namely, one arginase (SpARG1), two arginine decarboxylases (SpADC1, SpADC2), one agmatine iminohydrolase/deiminase (SpAIH), one N-carbamoyl putrescine amidase (SpCPA), three S-adenosylmethionine decarboxylases (SpSAMDc1, 2, 3), one spermidine synthase (SpSPDS1) and one spermine synthase (SpSPMS1) in S. polyrhiza genome were identified here. However, no locus was found for ODC pathway genes in this duckweed. Hidden Markov Model protein domain analysis established that SpADC1 is a prokaryotic/biodegradative type ADC and its molecular phylogenic classification fell in a separate prokaryotic origin ADC clade with SpADC2 as a biosynthetic type of arginine decarboxylase. However, thermospermine synthase (t-SPMS)/Aculis5 genes were not found present. Instead, one of the annotated SPDS may also function as SPMS, since it was found associated with the SPMS phylogenetic clade along with known SPMS genes. Moreover, we demonstrate that S. polyrhiza PA biosynthetic gene transcripts are differentially expressed in response to unfavorable conditions, such as exogenously added salt, methyl jasmonate, or acidic pH environment as well as in extreme temperature regimes. Thus, S. polyrhiza genome encodes for complete polyamine biosynthesis pathway and the genes are transcriptionally active in response to changing environmental conditions suggesting an important role of polyamines in this aquatic plant.


Assuntos
Araceae , Carboxiliases , Adenosilmetionina Descarboxilase/genética , Araceae/genética , Arginina , Carboxiliases/genética , Genômica , Ornitina Descarboxilase/genética , Filogenia , Poliaminas , Putrescina , Espermidina , Estresse Fisiológico/genética
2.
Mol Oral Microbiol ; 36(6): 308-315, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34486245

RESUMO

Polyamines are ubiquitous polycationic molecules that are present in all prokaryotic and eukaryotic cells, and they serve as important modulators of cell growth, stress, and cell proliferation. Polyamines are present at high concentrations in the periodontal pocket and could potentially affect the stress response of periodontal bacteria to antibiotics. The effects of polyamines on inhibition of growth by amoxicillin (AMX), azithromycin (AZM), and doxycycline (DOX) were investigated with the Y4 strain of Aggregatibacter actinomycetemcomitans (Aa). Bacteria were grown in brain heart infusion broth under the following conditions: (1) Aa only, (2) Aa + polyamine mix (1 mM putrescine, 0.4 mM spermidine, and 0.4 mM spermine), (3) Aa + antibiotic, and (4) Aa + antibiotic + polyamines. Growth curve analysis, minimal inhibitory concentration determination, and transcriptomic studies were conducted. The presence of exogenous polyamines produced a small, but significant increase in Aa growth, and polyamines attenuated the inhibitory effects of AMX, AZM, and DOX on growth. Transcriptomic analysis revealed that polyamines upregulate expression of ribosomal biogenesis proteins and small subunits, attenuate the bacterial stress response to antibiotics, and modulate bacterial nutritional pathways in a manner that could potentially increase the virulence of Aa. In summary, the polyamine-rich environment found in periodontal pockets appears to protect Aa and reduce its susceptibility to several antimicrobial agents in this in vitro model.


Assuntos
Aggregatibacter actinomycetemcomitans , Antibacterianos , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Poliaminas , Espermidina/farmacologia
3.
Nutrients ; 13(9)2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34578894

RESUMO

The polyamine content of human breast milk, which is the first exogenous source of polyamines for the newborn, can be affected by several factors associated with the mother, the infant, or breastfeeding itself. The aim of this study was to evaluate the influence of different breastfeeding factors on the polyamines found in human milk. For this study, a cohort of 83 mothers was considered for up to 4 months, and a subgroup of 33 mothers were followed during the first six months of breastfeeding. Two breast milk samples were collected at each sampling point (foremilk and hindmilk) and the polyamine content was determined by UHPLC-FL. Polyamine levels varied considerably between the mothers and tended to decrease over time. Putrescine was the minor polyamine, whereas spermidine and spermine contents were very similar. The concentrations of the three polyamines were significantly higher in hindmilk than foremilk (p < 0.001). Spermidine and spermine levels decreased significantly through the lactation progress (p < 0.05). Finally, slightly higher levels of polyamines were observed in the milk of mothers providing partial, rather than full, breastfeeding, although the differences were not significant. The polyamine content in human milk was found to change during a single feed (foremilk versus hindmilk) and as lactation progressed, mainly in response to the specific circumstances of the newborn.


Assuntos
Aleitamento Materno/métodos , Leite Humano/química , Poliaminas/análise , Adolescente , Adulto , Fatores Etários , Peso ao Nascer , Índice de Massa Corporal , Cromatografia Líquida de Alta Pressão , Estudos de Coortes , Parto Obstétrico/métodos , Feminino , Humanos , Lactente , Recém-Nascido , México , Mães , Poliaminas/química , Putrescina/análise , Espermidina/análise , Espermina/análise , Adulto Jovem
4.
Elife ; 102021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34517941

RESUMO

Microsatellite expansions of CCTG repeats in the cellular nucleic acid-binding protein (CNBP) gene leads to accumulation of toxic RNA and have been associated with myotonic dystrophy type 2 (DM2). However, it is still unclear whether the dystrophic phenotype is also linked to CNBP decrease, a conserved CCHC-type zinc finger RNA-binding protein that regulates translation and is required for mammalian development. Here, we show that depletion of Drosophila CNBP in muscles causes ageing-dependent locomotor defects that are correlated with impaired polyamine metabolism. We demonstrate that the levels of ornithine decarboxylase (ODC) and polyamines are significantly reduced upon dCNBP depletion. Of note, we show a reduction of the CNBP-polyamine axis in muscles from DM2 patients. Mechanistically, we provide evidence that dCNBP controls polyamine metabolism through binding dOdc mRNA and regulating its translation. Remarkably, the locomotor defect of dCNBP-deficient flies is rescued by either polyamine supplementation or dOdc1 overexpression. We suggest that this dCNBP function is evolutionarily conserved in vertebrates with relevant implications for CNBP-related pathophysiological conditions.


Assuntos
Proteínas de Drosophila/metabolismo , Atividade Motora/genética , Atividade Motora/fisiologia , Poliaminas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Animais Geneticamente Modificados , Linhagem Celular , Regulação para Baixo/fisiologia , Proteínas de Drosophila/genética , Drosophila melanogaster , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Músculo Esquelético/metabolismo , Distrofia Miotônica/genética , Distrofia Miotônica/metabolismo , Biossíntese de Proteínas , Putrescina/farmacologia , Interferência de RNA , Proteínas de Ligação a RNA/genética , Espermidina/farmacologia
5.
Molecules ; 26(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34443385

RESUMO

DNA origami nanostructures (DONs) are promising substrates for the single-molecule investigation of biomolecular reactions and dynamics by in situ atomic force microscopy (AFM). For this, they are typically immobilized on mica substrates by adding millimolar concentrations of Mg2+ ions to the sample solution, which enable the adsorption of the negatively charged DONs at the like-charged mica surface. These non-physiological Mg2+ concentrations, however, present a serious limitation in such experiments as they may interfere with the reactions and processes under investigation. Therefore, we here evaluate three approaches to efficiently immobilize DONs at mica surfaces under essentially Mg2+-free conditions. These approaches rely on the pre-adsorption of different multivalent cations, i.e., Ni2+, poly-l-lysine (PLL), and spermidine (Spdn). DON adsorption is studied in phosphate-buffered saline (PBS) and pure water. In general, Ni2+ shows the worst performance with heavily deformed DONs. For 2D DON triangles, adsorption at PLL- and in particular Spdn-modified mica may outperform even Mg2+-mediated adsorption in terms of surface coverage, depending on the employed solution. For 3D six-helix bundles, less pronounced differences between the individual strategies are observed. Our results provide some general guidance for the immobilization of DONs at mica surfaces under Mg2+-free conditions and may aid future in situ AFM studies.


Assuntos
Silicatos de Alumínio/química , DNA/química , Magnésio/química , Microscopia de Força Atômica , Nanoestruturas/química , Conformação de Ácido Nucleico , Adsorção , Níquel/química , Polieletrólitos/química , Polilisina/química , Espermidina/química , Propriedades de Superfície , Água/química
6.
Int J Mol Sci ; 22(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34445589

RESUMO

Crohn's Disease (CD) and Rheumatoid Arthritis (RA) share some single nucleotide polymorphisms (SNPs) in protein tyrosine phosphatase non-receptor types 2 and 22 (PTPN2/22). Recently, we reported that clinical samples from CD and RA patients associated with PTPN2:rs478582 or PTPN22:rs2476601 genotypes were linked to overactive immune response and exacerbation of inflammation. Here, we investigated in vitro the effects of these SNPs in Jurkat T-cells using CRISPR-Cas9. All cells were evaluated for PTPN22/22 loss of function and effects on cell response. We measured gene expression via RT-qPCR and cytokines by ELISA. We also measured cell proliferation using a BrdU labeling proliferation ELISA, and T-cell activation using CD-25 fluorescent immunostaining. In PTPN2 SNP-edited cells, PTPN2 expression decreased by 3.2-fold, and proliferation increased by 10.2-fold compared to control. Likewise, expression of PTPN22 decreased by 2.4-fold and proliferation increased by 8.4-fold in PTPN22 SNP-edited cells. IFN-γ and TNF-α secretions increased in both edited cell lines. CD25 expression (cell activation) was 80.32% in PTPN2 SNP-edited cells and 85.82% in PTPN22 SNP-edited cells compared to 70.48% in unedited Jurkat T-cells. Treatment of PTPN2 and PTPN22-edited cells with a maximum 20 µM spermidine restored PTPN2/22 expression and cell response including cell proliferation, activation, and cytokines secretion. Most importantly, the effect of spermidine on edited cells restored normal expression and secretion of IFN-γ and TNF-α. The data clearly demonstrated that edited SNPs in PTPN2 or PTPN22 were associated with reduced gene expression, which resulted in an increase in cell proliferation and activation and overactive immune response. The data validated our earlier observations in CD and RA clinical samples. Surprisingly, spermidine restored PTPN2/22 expression in edited Jurkat T-cells and the consequent beneficial effect on cell response and inflammation. The study supports the use of polyamines dietary supplements for management of CD and in RA patients.


Assuntos
Sistemas CRISPR-Cas , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia de Células T/patologia , Polimorfismo de Nucleotídeo Único , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Proteína Tirosina Fosfatase não Receptora Tipo 2/genética , Espermidina/farmacologia , Artrite Reumatoide/genética , Doença de Crohn/genética , Predisposição Genética para Doença , Humanos , Células Jurkat , Leucemia de Células T/tratamento farmacológico , Leucemia de Células T/genética , Ativação Linfocitária , Proteína Tirosina Fosfatase não Receptora Tipo 2/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 2/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 22/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 22/metabolismo
7.
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
8.
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
9.
Artigo em Inglês | MEDLINE | ID: mdl-34323678

RESUMO

A Gram-stain-negative, aerobic and non-motile bacterium, strain sand1-3T, was isolated from beach sand collected from Haeundae Beach located in Busan, Republic of Korea. Based on the results of 16S rRNA gene sequence and phylogenetic analyses, Sphingomonas daechungensis CH15-11T (97.0 %), Sphingomonas edaphi DAC4T (96.8 %), Sphingomonas xanthus AE3T (96.5 %) and Sphingomonas oryziterrae YC6722T (96.0 %) were selected for comparing phenotypic and chemotaxonomic characteristics. Cells of strain sand1-3T grew at 7-50 °C (optimum, 30-35 °C), pH 5.0-8.0 (optimum, pH 7.0-8.0) and in the presence of 0-0.5 % (w/v) NaCl (optimum, 0 %). Major polar lipids included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid, one unidentified glycolipid and one unidentified phosphoglycolipid. The major fatty acids were summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c) and C18 : 1 2-OH. Moreover, the sole respiratory quinone and major polyamine were identified as ubiquinone-10 and homospermidine, respectively. The genomic DNA G+C content was 65.9 mol%. The digital DNA-DNA hybridization, average nucleotide identity and average amino acid identity values of strain sand1-3T and its reference strains with publicly available genomes were 17.9-18.9 %, 72.0-75.3 % and 63.3-76.5 % respectively. Based on polyphasic evidence, we propose Sphingomonas sabuli sp. nov. as a novel species within the genus Sphingomonas. The type strain is sand1-3T (=KCTC 82358T=NBRC 114538T).


Assuntos
Sphingomonas , Técnicas de Tipagem Bacteriana , Composição de Bases , Carotenoides , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Areia , Análise de Sequência de DNA , Microbiologia do Solo , Espermidina , Sphingomonas/genética
10.
Microb Pathog ; 158: 105076, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34216740

RESUMO

The urease enzyme of Cryptococcus neoformans is linked to different metabolic pathways within the yeast cell, several of which are involved in polyamine metabolism. Cryptococcal biogenic amine production is, however, largely unexplored and is yet to be investigated in relation to urease. The aim of this study was therefore to explore and compare polyamine metabolism in wild-type, urease-negative and urease-reconstituted strains of C. neoformans. Mass spectrometry analysis showed that agmatine and spermidine were the major extra- and intracellular polyamines of C. neoformans and significant differences were observed between 26 and 37 °C. In addition, compared to the wild-type, the relative percentages of extracellular putrescine and spermidine were found to be lower and agmatine higher in cultures of the urease-deficient mutant. The inverse was true for intracellular spermidine and agmatine. Cyclohexylamine was a more potent polyamine inhibitor compared to DL-α-difluoromethylornithine and inhibitory effects were more pronounced at 37 °C than at 26 °C. At both temperatures, the urease-deficient mutant was less susceptible to cyclohexylamine treatment compared to the wild-type. For both inhibitors, growth inhibition was alleviated with polyamine supplementation. This study has provided novel insight into the polyamine metabolism of C. neoformans, highlighting the involvement of urease in biogenic amine production.


Assuntos
Cryptococcus neoformans , Poliaminas/metabolismo , Urease/metabolismo , Putrescina , Espermidina
11.
Obes Res Clin Pract ; 15(4): 315-326, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34217652

RESUMO

Spermidine is a natural polyamine existing in all living cells known to play an important role in cellular functions. Recently, several studies have reported the effect of alterations in the spermidine pool on metabolic pathways. It has been shown that activation of spermidine/spermine N-1-acetyl-transferase (SSAT), the rate-limiting enzyme in polyamine catabolism, improved glucose and lipid metabolism. In addition, spermidine supplementation has been shown to protect against diet-induced obesity in animal models. However, some clinical studies demonstrated that polyamine levels are increased in childhood obesity and metabolic syndrome patients with type 2 diabetes (T2DM), while polyamine-rich food is associated with a lower incidence of cardiovascular disease (CVD). Therefore, this review aims to summarize and discuss the evidence from in vitro, in vivo and clinical studies on the possible roles of spermidine on metabolic pathways under physiological and obese conditions. All consistent and inconsistent findings are discussed and further studies aiming to fill any gaps in the knowledge are proposed.


Assuntos
Diabetes Mellitus Tipo 2 , Obesidade Pediátrica , Animais , Criança , Diabetes Mellitus Tipo 2/etiologia , Glucose , Humanos , Poliaminas , Espermidina
12.
Carbohydr Polym ; 269: 118335, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34294345

RESUMO

Recently, the hydrogel-forming polysaccharide gellan gum (GG) has gained popularity as a versatile biomaterial for tissue engineering purposes. Here, we examine the modification strategies suitable for GG to overcome processing-related limitations. We emphasize the thorough assessment of the viscoelastic and mechanical properties of both precursor solutions and final hydrogels. The investigated modification strategies include purification, oxidation, reductive chain scission, and blending. We correlate polymer flow and hydrogel forming capabilities to viscosity-dependent methods including casting, injection and printing. Native GG and purified NaGG are shear thinning and feasible for printing, being similar in gelation and compression behavior. Oxidized GGox possesses reduced viscosity, higher toughness, and aldehydes as functional groups, while scissored GGsciss has markedly lower molecular weight. To exemplify extrudability, select modification products are printed using an extrusion-based bioprinter utilizing a crosslinker bath. Our robust modification strategies have widened the processing capabilities of GG without affecting its ability to form hydrogels.


Assuntos
Polissacarídeos Bacterianos/química , Cloreto de Cálcio/química , Hidrogéis/síntese química , Hidrogéis/química , Teste de Materiais , Peso Molecular , Oxirredução , Polissacarídeos Bacterianos/síntese química , Espermidina/química , Substâncias Viscoelásticas/síntese química , Substâncias Viscoelásticas/química , Viscosidade
13.
Appl Microbiol Biotechnol ; 105(12): 5039-5051, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34142206

RESUMO

Heat stress (HS) is inescapable environmental stress that can induce the production of ganoderic acids (GAs) in Ganoderma lucidum. Our previous studies found that putrescine (Put) played an inhibitory role in GAs biosynthesis, which appeared to be inconsistent with the upregulated transcription of the Put biosynthetic gene GlOdc under HS. To uncover the mechanism underlying this phenomenon, two spermidine (Spd) biosynthetic genes, GlSpds1 and GlSpds2, were identified and upregulated under HS. Put and Spd increased by 94% and 160% under HS, respectively, suggesting that HS induces polyamine biosynthesis and promotes the conversion of Put to Spd. By using GlSpds knockdown mutants, it is confirmed that Spd played a stimulatory role in GAs biosynthesis. In GlOdc-kd mutants, Put decreased by 62-67%, Spd decreased by approximately 34%, and GAs increased by 15-22% but sharply increased by 75-89% after supplementation with Spd. In GlSpds-kd mutants, Put increased by 31-41%, Spd decreased by approximately 63%, and GAs decreased by 24-32% and were restored to slightly higher levels than a wild type after supplementation with Spd. This result suggested that Spd, rather than Put, is a crucial factor that leads to the accumulation of GAs under HS. Spd plays a more predominant and stimulative role than Put under HS, possibly because the absolute content of Spd is 10 times greater than that of Put. GABA and H2O2, two major catabolites of Spd, had little effect on GAs biosynthesis. This study provides new insight into the mechanism by which environmental stimuli regulate secondary metabolism via polyamines in fungi. KEY POINTS: • HS induces polyamine biosynthesis and promotes the conversion of Put to Spd in G. lucidum. • Put and Spd played the inhibitory and stimulatory roles in regulating GAs biosynthesis, respectively. • The stimulatory role of Spd was more predominant than the inhibitory role of Put in GAs biosynthesis.


Assuntos
Reishi , Espermidina , Resposta ao Choque Térmico , Peróxido de Hidrogênio , Putrescina , Triterpenos
14.
Nat Commun ; 12(1): 3818, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34155207

RESUMO

Viruses manipulate cellular metabolism and macromolecule recycling processes like autophagy. Dysregulated metabolism might lead to excessive inflammatory and autoimmune responses as observed in severe and long COVID-19 patients. Here we show that SARS-CoV-2 modulates cellular metabolism and reduces autophagy. Accordingly, compound-driven induction of autophagy limits SARS-CoV-2 propagation. In detail, SARS-CoV-2-infected cells show accumulation of key metabolites, activation of autophagy inhibitors (AKT1, SKP2) and reduction of proteins responsible for autophagy initiation (AMPK, TSC2, ULK1), membrane nucleation, and phagophore formation (BECN1, VPS34, ATG14), as well as autophagosome-lysosome fusion (BECN1, ATG14 oligomers). Consequently, phagophore-incorporated autophagy markers LC3B-II and P62 accumulate, which we confirm in a hamster model and lung samples of COVID-19 patients. Single-nucleus and single-cell sequencing of patient-derived lung and mucosal samples show differential transcriptional regulation of autophagy and immune genes depending on cell type, disease duration, and SARS-CoV-2 replication levels. Targeting of autophagic pathways by exogenous administration of the polyamines spermidine and spermine, the selective AKT1 inhibitor MK-2206, and the BECN1-stabilizing anthelmintic drug niclosamide inhibit SARS-CoV-2 propagation in vitro with IC50 values of 136.7, 7.67, 0.11, and 0.13 µM, respectively. Autophagy-inducing compounds reduce SARS-CoV-2 propagation in primary human lung cells and intestinal organoids emphasizing their potential as treatment options against COVID-19.


Assuntos
COVID-19/metabolismo , COVID-19/virologia , SARS-CoV-2/metabolismo , Animais , Antinematódeos/farmacologia , Autofagossomos/metabolismo , Autofagia , Proteínas Relacionadas à Autofagia/metabolismo , COVID-19/tratamento farmacológico , COVID-19/patologia , Células Cultivadas , Chlorocebus aethiops , Cricetinae , Modelos Animais de Doenças , Humanos , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Metaboloma , Niclosamida/farmacologia , Organoides , SARS-CoV-2/isolamento & purificação , Espermidina/farmacologia , Espermina/farmacologia
15.
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
16.
J Cell Sci ; 134(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34096604

RESUMO

In Saccharomyces cerevisiae, the selective autophagic degradation of mitochondria, termed mitophagy, is critically regulated by the adapter protein Atg32. Despite our knowledge about the molecular mechanisms by which Atg32 controls mitophagy, its physiological roles in yeast survival and fitness remains less clear. Here, we demonstrate a requirement for Atg32 in promoting spermidine production during respiratory growth and heat-induced mitochondrial stress. During respiratory growth, mitophagy-deficient yeast exhibit profound heat-stress induced defects in growth and viability due to impaired biosynthesis of spermidine and its biosynthetic precursor S-adenosyl methionine. Moreover, spermidine production is crucial for the induction of cytoprotective nitric oxide (NO) during heat stress. Hence, the re-addition of spermidine to Atg32 mutant yeast is sufficient to both enhance NO production and restore respiratory growth during heat stress. Our findings uncover a previously unrecognized physiological role for yeast mitophagy in spermidine metabolism and illuminate new interconnections between mitophagy, polyamine biosynthesis and NO signaling.


Assuntos
Mitofagia , Proteínas de Saccharomyces cerevisiae , Autofagia/genética , Proteínas Relacionadas à Autofagia/genética , Resposta ao Choque Térmico/genética , Óxido Nítrico , Receptores Citoplasmáticos e Nucleares , Proteínas de Saccharomyces cerevisiae/genética , Espermidina
17.
Food Chem ; 361: 130044, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34049048

RESUMO

A method for the determination of 8 biogenic amines in aquatic products and their derived products was established by HPLC-MS/MS without derivatization. The samples were extracted by 5% perchloric acid solution. N-hexane was used to clean the extract. The analytes were separated by a column of ACQUITY UPLC HSS T3 (100 mm × 2.1 mm, 1.8 µm), and gradient eluted with a mixed solution of (0.5% formic acid) and acetonitrile. Good linearity was obtained with correlation coefficients (R2) >0.99. This method achieved higher sensitivity (from 0.1 mg/kg for tyramine, 2-phenylethylamine and tryptamine to 1.0 mg/kg for spermidine, spermine, cadaverin, histamine and putrescine). The average recoveries were demonstrated in the range of 70.9%-113.1%, with relative standard deviations (RSDs) from 0.33% to 10.81%. This method was suitable for the detection of BAs in aquatic products and their products.


Assuntos
Aminas Biogênicas/análise , Cromatografia Líquida de Alta Pressão/métodos , Alimentos Marinhos/análise , Espectrometria de Massas em Tandem/métodos , Cadaverina/análise , Histamina/análise , Fenetilaminas/análise , Putrescina/análise , Espermidina/análise , Espermina/análise , Triptaminas/análise , Tiramina/análise
18.
J Cell Sci ; 134(9)2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33973637

RESUMO

Stem cell differentiation is accompanied by increased mRNA translation. The rate of protein biosynthesis is influenced by the polyamines putrescine, spermidine and spermine, which are essential for cell growth and stem cell maintenance. However, the role of polyamines as endogenous effectors of stem cell fate and whether they act through translational control remains obscure. Here, we investigate the function of polyamines in stem cell fate decisions using hair follicle stem cell (HFSC) organoids. Compared to progenitor cells, HFSCs showed lower translation rates, correlating with reduced polyamine levels. Surprisingly, overall polyamine depletion decreased translation but did not affect cell fate. In contrast, specific depletion of natural polyamines mediated by spermidine/spermine N1-acetyltransferase (SSAT; also known as SAT1) activation did not reduce translation but enhanced stemness. These results suggest a translation-independent role of polyamines in cell fate regulation. Indeed, we identified N1-acetylspermidine as a determinant of cell fate that acted through increasing self-renewal, and observed elevated N1-acetylspermidine levels upon depilation-mediated HFSC proliferation and differentiation in vivo. Overall, this study delineates the diverse routes of polyamine metabolism-mediated regulation of stem cell fate decisions. This article has an associated First Person interview with the first author of the paper.


Assuntos
Folículo Piloso , Espermina , Acetiltransferases/genética , Diferenciação Celular , Espermidina , Células-Tronco
19.
Cryobiology ; 100: 72-76, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33794189

RESUMO

In this study, the effects of polyamines, Spermine and Spermidine, on long-term preservation and post-thaw spermatological parameters were evaluated. Moreover, determination of the most suitable polyamine and its dose that can be added to standard extenders were aimed. Four adult Arabian stallions were used in the study. Five ejaculates were collected from each of four stallions via artificial vagina two days interval. Each ejaculate was divided into 13 aliquots. INRA96 (95,5%), egg yolk (2%), and glycerol (2,5%) were used as a control extender. Extenders of experimental groups were prepared with different doses of Spermine and Spermidine (0,1 mg/ml; 0,2 mg/ml; 0,4 mg/ml; 1 mg/ml; 2 mg/ml; 4 mg/ml). Stallion semen that were cryopreserved with Control and experimental extenders were evaluated in terms of Total Motility, Progressive Motility, Plasma Membrane Integrity, Capacitation Index, Acrosome Integrity and DNA Fragmentation Index. At the end of the evaluations, it was determined that 0,2 mg/ml Spermine and 0,4 mg/ml Spermidine showed better Total Motility and Progressive Motility, numerically. On the other hand, it was observed that 4 mg/ml Spermine and Spermidine had the lowest statistically significant values (p < 0,001). While statistically similar differences were obtained between groups in terms of the Plasma Membrane and Acrosome Integrity, it was determined that all experimental groups had lower and statistically significant values in terms of Capacitation and DNA Fragmentation Index (p < 0,001). As result, it was observed that the stallion semen cryopreservation success can be increased by the addition of 1-2 mg/ml Spermine that had effective protection on Capacitation and DNA Fragmentation Index without damaging other spermatological properties.


Assuntos
Preservação do Sêmen , Sêmen , Animais , Criopreservação/métodos , Crioprotetores/farmacologia , Feminino , Cavalos , Humanos , Masculino , Preservação do Sêmen/veterinária , Motilidade Espermática , Espermatozoides , Espermidina/farmacologia , Espermina/farmacologia
20.
Molecules ; 26(6)2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33810101

RESUMO

To date, there is no effective treatment for alcoholic liver disease, despite its prevalence world-wide. Because alcohol consumption is associated with oxidative stress-induced liver injury and pro-inflammatory responses, naturally occurring antioxidants and/or anti-inflammatories may be potential therapeutics. Spermidine is an abundant, ubiquitous polyamine that has been found to display strong antioxidant and anti-inflammatory properties. To further investigate whether spermidine is an effective intervention for alcohol-induced liver disease, we examined its hepatoprotective properties using a two-hit, chronic ethanol and acute lipopolysaccharide (LPS)-induced mouse model of liver injury. We determined that spermidine administration prevented ethanol and LPS-induced increases in liver injury using plasma ALT as a readout. Furthermore, histological analysis of tissue from control and treated animals revealed that the pathology associated with ethanol and LPS treatment was prevented in mice additionally treated with spermidine. As predicted, spermidine also prevented ethanol and LPS-induced oxidative stress by decreasing the levels of both reactive oxygen species (ROS) and lipid peroxidation. We further determined that spermidine treatment prevented the nuclear translocation of nuclear factor κB (NFκB) by blocking the phosphorylation of the inhibitory protein, IκB, thereby preventing expression of pro-inflammatory cytokines. Finally, by measuring expression of known markers of hepatic stellate cell activation and monitoring collagen deposition, we observed that spermidine also prevented alcohol and LPS-induced hepatic fibrosis. Together, our results indicate that spermidine is an antioxidant thereby conferring anti-inflammatory and anti-fibrotic effects associated with alcoholic liver injury.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Etanol/toxicidade , Lipopolissacarídeos/toxicidade , Hepatopatias Alcoólicas/prevenção & controle , Fígado/metabolismo , Espermidina/farmacologia , Animais , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Feminino , Fígado/patologia , Hepatopatias Alcoólicas/metabolismo , Hepatopatias Alcoólicas/patologia , Camundongos
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