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1.
Mar Drugs ; 22(5)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38786613

RESUMO

Porphyra sensu lato has economic importance for food and pharmaceutical industries due to its significant physiological activities resulting from its bioactive compounds (BACs). This study aimed to determine the optimal nitrate dosage required in short-term cultivation to achieve substantial BAC production. A nitrate experiment using varied concentrations (0 to 6.5 mM) revealed optimal nitrate uptake at 0.5 mM in the first two days and at 3 and 5 mM in the last five days. Polyphenols and carbohydrates showed no differences between treatments, while soluble proteins peaked at 1.5 and 3 mM. Total mycosporine-like amino acids (MAAs) were highest in algae incubated at 5 and 6.5 mM, and the highest antioxidant activity was observed in the 5 mM, potentially related to the MAAs amount. Total carbon and sulfur did not differ between treatments, while nitrogen decreased at higher nitrate. This discovery highlights the nuanced role of nitrate in algal physiology, suggesting that biological and chemical responses to nitrate supplementation can optimize an organism's health and its commercially significant bioactive potential. Furthermore, given its ability to absorb high doses of nitrate, this alga can be cultivated in eutrophic zones or even in out-/indoor tanks, becoming an excellent option for integrated multi-trophic aquaculture (IMTA) and bioremediation.


Assuntos
Antioxidantes , Biodegradação Ambiental , Nitratos , Porphyra , Nitratos/metabolismo , Nitratos/farmacologia , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Porphyra/metabolismo , Cosmecêuticos , Aminoácidos/metabolismo
2.
J Inorg Biochem ; 256: 112554, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38613885

RESUMO

Six terpyridine­nickel complexes 1-6 were formed by the coordination of 4'-(4-R-phenyl)-2,2':6',2″-terpyridine (R = hydroxyl (L1), methoxyl (L2), methylsulfonyl (L3), fluoro (L4), bromo (L5), iodo (L6)) derivatives to nickel nitrate. The compositions and structures of these complexes were analyzed by Fourier Transform infrared spectroscopy (FT-IR), elemental analyses, electrospray ionization mass spectra (ESI-MS), solid-state ultraviolet-visible (UV-Vis) spectroscopy, and single crystal X-ray diffraction (1, 2 and 4) studies. In vitro anticancer cell proliferation experiments against SiHa (human cervical squamous cancer cell line) cells, Bel-7402 (human hepatoma cancer cell line), Eca-109 (human esophageal cancer cell line) and HL-7702 (human normal hepatocyte cell line) indicate that they have more excellent anti-proliferation effects than the cis-platin against Siha cells, Bel-7402 cells and Eca-109 cells. Especially, complex 5 showed a rather outstanding inhibitory effect against the SiHa cell line and was less toxic than the other compounds to the HL-7702 cell line, implying an obvious specific inhibitory effect. Therefore, complex 5 has the potential value to be developed as an anticancer cell-specific drug against human cervical squamous carcinoma. Molecular docking simulation, UV-vis absorption spectroscopy and circular dichroism experiments show that they prefer to bind to DNA part in an embedded binding manner.


Assuntos
Antineoplásicos , Complexos de Coordenação , Níquel , Piridinas , Humanos , Níquel/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Piridinas/química , Piridinas/farmacologia , Proliferação de Células/efeitos dos fármacos , Nitratos/química , Nitratos/farmacologia , Cristalografia por Raios X
3.
Environ Sci Pollut Res Int ; 31(10): 15946-15957, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38308781

RESUMO

Nitrogen forms can affect metal accumulation in plants and tolerance to metals, but a few published studies on the effects on Cu toxicity and Cu accumulation in plants are scarce. Thus, the objective of this study was to evaluate the responses of Liriodendron chinense to different nitrogen forms, by the oxidative stress, antioxidant enzymes system, GSH-AsA cycle, Cu uptake, translocation, and accumulation under Cu stress. We found that Cu-induced growth inhibiting was alleviated by added exclusive NO3--N. Adding N as NH4+-N with or without NO3--N was aggravated as evidenced by significantly elevated malonaldehyde (MDA) and hydrogen peroxide (H2O2) compared to N-Null. Cu exposure and adding NH4+-N inhibited superoxide dismutase activity, but remarkably stimulated the activities of catalase and peroxidase, the efficiency of glutathione-ascorbate (GSH-AsA) cycle, and the activity of glutathione reductase and nitrate reductase, with respect to the control. However, adding exclusive NO3--N progressively restored the alteration of antioxidant to prevent Cu-induced oxidative stress. Additionally, adding exclusive NO3--N significantly promoted the Cu uptake and accumulation in roots, but reduced Cu concentration in leaves, accompanied by the inhibited Cu translocation factor from roots to shoots by 36.7%, when compared with N-Null. Overall, adding NO3--N alleviated its Cu toxicity by preventing Cu-induced oxidative stress and inhibiting Cu translocation from roots to shoots, which provides an effective strategy for phytostabilization in Cu-contaminated lands.


Assuntos
Cobre , Liriodendron , Cobre/toxicidade , Antioxidantes/metabolismo , Nitratos/farmacologia , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo , Glutationa/metabolismo , Nitrogênio/farmacologia , Raízes de Plantas/metabolismo
4.
Sci Rep ; 14(1): 2764, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38308017

RESUMO

Aquatic biota are threatened by climate warming as well as other anthropogenic stressors such as eutrophication by phosphates and nitrate. However, it remains unclear how nitrate exposure can alter the resilience of microalgae to climate warming, particularly heatwaves. To get a better understanding of these processes, we investigated the effect of elevated temperature and nitrate pollution on growth, metabolites (sugar and protein), oxidative damage (lipid peroxidation), and antioxidant accumulation (polyphenols, proline) in Chlamydomonas reinhardtii and Pseudokirchneriella subcapitata. The experiment involved a 3 × 3 factorial design, where microalgae were exposed to one of three nitrate levels (5, 50, or 200 mg L-1 NO3-l) at 20 °C for 2 weeks. Subsequently, two heatwave scenarios were imposed: a short and moderate heatwave at 24 °C for 2 weeks, and a long and intense heatwave with an additional 2 weeks at 26 °C. A positive synergistic effect of heatwaves and nitrate on growth and metabolites was observed, but this also led to increased oxidative stress. In the short and moderate heatwave, oxidative damage was controlled by increased antioxidant levels. The high growth, metabolites, and antioxidants combined with low oxidative stress during the short and moderate heatwaves in moderate nitrate (50 mg L-1) led to a sustainable increased food availability to grazers. On the other hand, long and intense heatwaves in high nitrate conditions caused unsustainable growth due to increased oxidative stress and relatively low antioxidant (proline) levels, increasing the risk for massive algal die-offs.


Assuntos
Chlamydomonas reinhardtii , Microalgas , Antioxidantes/metabolismo , Nitratos/farmacologia , Microalgas/metabolismo , Chlamydomonas reinhardtii/metabolismo , Prolina/farmacologia
5.
Biol Trace Elem Res ; 202(3): 1009-1019, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37335444

RESUMO

To study the species of lanthanum (III) nitrate (La[NO3]3) dispersed in cell media and the effect on the osteoblast differentiation of bone marrow stroma cells (BMSCs). Different La-containing precipitations were obtained by adding various concentrations of La(NO3)3 solutions to Dulbecco's modified Eagle medium (DMEM) or DMEM with fetal bovine serum (FBS). A series of characterisation methods, including dynamic light scattering, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and protein quantification were employed to clarify the species of the different La-containing precipitations. The primary BMSCs were isolated, and the cell viability, alkaline phosphatase activity, and the formation of a mineralised nodule of BMSCs were tested when treated with different La-containing precipitations. The La(NO3)3 solutions in DMEM could form LaPO4, which exits in the particle formation, while the La(NO3)3 solutions in DMEM with FBS could form a La-PO4-protein compound. When treated with La(NO3)3 solutions in DMEM, the cell viability of the BMSCs was inhibited at the concentrations of 1, 10, and 100 µM at 1 day and 3 days. Meanwhile, the supernatant derived from the La(NO3)3 solutions in DMEM did not affect the cell viability of the BMSCs. In addition, the precipitate derived from the La(NO3)3 solutions in DMEM added to the complete medium inhibited the cell viability of the BMSCs at concentrations of 10 µM and 100 µM. When treated with La(NO3)3 solutions in DMEM with FBS, the derived precipitate and supernatant did not affect the cell viability of the BMSCs, except for the concentration of 100 µM La(NO3)3. The La-PO4-protein formed from the La(NO3)3 solutions in DMEM with FBS inhibited the osteoblast differentiation of BMSCs at the concentration of 1 µM La(NO3)3 (P < 0.05) but had no effect on either the osteoblast differentiation at the concentrations of 0.001 and 0.1 µM or on the formation of a mineralised nodule at all tested concentrations of La(NO3)3. Overall, La(NO3)3 solutions in different cell culture media could form different La-containing compounds: La-PO4 particles (in DMEM) and a La-PO4-protein compound (in DMEM with FBS). The different La-containing compounds caused different effects on the cell viability, osteoblast differentiation, and the formation of a mineralised nodule of the BMSCs. The La-containing precipitation inhibited the osteoblast differentiation by inhibiting the expression of osteoblast-related genes and proteins, providing a theoretical basis for clinical doctors to apply phosphorus-lowering drugs such as lanthanum carbon.


Assuntos
Células-Tronco Mesenquimais , Nitratos , Camundongos , Animais , Nitratos/farmacologia , Nitratos/metabolismo , Lantânio/farmacologia , Lantânio/metabolismo , Osteogênese , Células Cultivadas , Diferenciação Celular , Células da Medula Óssea , Proliferação de Células , Células Estromais
6.
Sci Prog ; 106(4): 368504231219171, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38113117

RESUMO

The tobacco cutworm (Spodoptera litura) is a widespread pest that inflicts severe damage on various crops, including cotton, tobacco, and vegetables, with a particular preference for solanaceous plants. Traditional control methods often rely heavily on synthetic insecticides, leading to adverse effects on the environment, human health, and the development of insecticide resistance. In light of these challenges, this study explores the potential of nanotechnology as an innovative and sustainable approach to combat this notorious pest. Bioassays were conducted using laboratory-reared 3rd instar S. litura larvae. Eight different plant extracts coated with zinc oxide and silver nitrate nanoparticles were tested, with concentrations in both distilled water and ethanol at 3, 5, and 7 ml. Data were collected at 24, 48, and 72-h intervals. The results revealed that the highest larval mortality, reaching 98%, was observed in the group treated with silver nitrate nanoparticles derived from Cymbopogon citratus. In comparison, the group treated with zinc oxide nanoparticles dissolved in ethanol exhibited a larval mortality rate of 90%. Ethanol is a polar solvent that is widely used in the synthesis of nanocomposites. It is capable of forming strong hydrogen bonds with oxygen atoms, making it a good dispersant for zinc oxide nanoparticles. Additionally, ethanol has a low boiling point and a non-toxic nature, which makes it a safe and effective option for the dispersion of nanoparticles. Notably, the study concluded that silver nanoparticles combined with ethanol exhibited prolonged and more potent toxic effects against S. litura when compared to zinc oxide nanoparticles. Overall, this research underscores the potential of nanotechnology as a valuable component of Integrated Pest Management (IPM) strategies. By integrating nanotechnology into pest management practices, we can promote sustainable and environmentally friendly approaches that benefit both farmers and the ecosystem.


Assuntos
Nanopartículas Metálicas , Controle de Pragas , Óxido de Zinco , Animais , Ecossistema , Etanol , Larva , Nanopartículas Metálicas/toxicidade , Nitratos/farmacologia , Extratos Vegetais/farmacologia , Prata/farmacologia , Nitrato de Prata/farmacologia , Spodoptera , Óxido de Zinco/farmacologia
7.
BMC Genomics ; 24(1): 633, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872493

RESUMO

Nitrate is a primary nitrogen source for plant growth, and previous studies have indicated a correlation between nitrogen and browning. Nitrate transporters (NRTs) are crucial in nitrate allocation. Here, we utilized a genome-wide approach to identify and analyze the expression pattern of 74 potential GbNRTs under nitrate treatments during calluses browning in Ginkgo, including 68 NITRATE TRANSPORTER 1 (NRT1)/PEPTIDE TRANSPORTER (PTR) (NPF), 4 NRT2 and 2 NRT3. Conserved domains, motifs, phylogeny, and cis-acting elements (CREs) were analyzed to demonstrate the evolutionary conservation and functional diversity of GbNRTs. Our analysis showed that the NPF family was divided into eight branches, with the GbNPF2 and GbNPF6 subfamilies split into three groups. Each GbNRT contained 108-214 CREs of 19-36 types, especially with binding sites of auxin and transcription factors v-myb avian myeloblastosis viral oncogene homolog (MYB) and basic helix-loop-helix (bHLH). The E1X1X2E2R motif had significant variations in GbNPFs, indicating changes in the potential dynamic proton transporting ability. The expression profiles of GbNRTs indicated that they may function in regulating nitrate uptake and modulating the signaling of auxin and polyphenols biosynthesis, thereby affecting browning in Ginkgo callus induction. These findings provide a better understanding of the role of NRTs during NO3- uptake and utilization in vitro culture, which is crucial to prevent browning and develop an efficient regeneration and suspension production system in Ginkgo.


Assuntos
Nitratos , Proteínas de Plantas , Nitratos/farmacologia , Nitratos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ginkgo biloba/genética , Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/química , Proteínas de Transporte de Ânions/metabolismo , Transportadores de Nitrato , Nitrogênio/metabolismo , Ácidos Indolacéticos , Regulação da Expressão Gênica de Plantas , Filogenia
8.
BMC Complement Med Ther ; 23(1): 282, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553559

RESUMO

Hypertension is among the risk factors of death globally. Novel antihypertensive peptides are alternative choices of antihypertensive assistance. This study aimed to discover novel antihypertensive peptides from green basil leaves. Two bioactive peptides with high angiotensin-converting enzyme inhibition (Asp-Leu-Ser-Ser-Ala-Pro; peptide 1) and antioxidant (Asp-Ser-Val-Ser-Ala-Ser-Pro; peptide 2) activities were gavaged to male Wistar rats induced with NG-nitro-l-arginine methyl-ester (L-NAME). L-NAME-treated rats (HT) had decreased body weights and levels of nitrite and nitrate, which are metabolites of nitric oxide. The levels of their glucose and liver function indicators increased as compared to normal rats. HT rats receiving antihypertensive drugs (HTD) showed higher low-density lipoprotein and low-density lipoprotein/high-density lipoprotein levels than HT rats. Peptide 1 seems to benefit the rat lipid profiles, liver functions, antioxidant, nitrite, nitrate, and angiotensin II peptide levels but not peptide 2. In conclusion, our findings indicate the antihypertensive potential related to vasodilation of peptides from green basil leaves.


Assuntos
Anti-Hipertensivos , Ocimum basilicum , Ratos , Masculino , Animais , Anti-Hipertensivos/farmacologia , NG-Nitroarginina Metil Éster/farmacologia , Nitritos , Nitratos/farmacologia , Antioxidantes/farmacologia , Ratos Wistar , Pressão Sanguínea , Peptídeos/farmacologia , Lipoproteínas LDL , Folhas de Planta
9.
Ann Clin Microbiol Antimicrob ; 22(1): 61, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37475017

RESUMO

BACKGROUND: Biofilms play a role in recalcitrance and treatability of bacterial infections, but majority of known antibiotic resistance mechanisms are biofilm-independent. Biofilms of Pseudomonas aeruginosa, especially in cystic fibrosis patients infected with the alginate producing strains in their lungs, are hard to treat. Changes in growth-related bacterial metabolism in biofilm affect their antibiotic recalcitrance which could be considered for new therapies designed based on these changes. In this study, effects of nitrate, arginine, and ferrous were investigated on antibiotic recalcitrance in alginate-encapsulated P. aeruginosa strains isolated from cystic fibrosis patients in the presence of amikacin, tobramycin, and ciprofloxacin. Also, expression of an efflux pump gene, mexY, was analyzed in selected strains in the presence of amikacin and ferrous. METHODS: Clinical P. aeruginosa strains were isolated from cystic fibrosis patients and minimum inhibitory concentration of amikacin, tobramycin, and ciprofloxacin was determined against all the strains. For each antibiotic, a susceptible and a resistant or an intermediate-resistant strain were selected, encapsulated into alginate beads, and subjected to minimal biofilm eradication concentration (MBEC) test. After determining MBECs, sub-MBEC concentrations (antibiotics at concentrations one level below the determined MBEC) for each antibiotic were selected and used to study the effects of nitrate, arginine, and ferrous on antibiotic recalcitrance of encapsulated strains. Effects of ferrous and amikacin on expression of the efflux pump gene, mexY, was studied on amikacin sensitive and intermediate-resistant strains. One-way ANOVA and t test were used as the statistical tests. RESULTS: According to the results, the supplements had a dose-related effect on decreasing the number of viable cells; maximal effect was noted with ferrous, as ferrous supplementation significantly increased biofilm susceptibility to both ciprofloxacin and amikacin in all strains, and to tobramycin in a resistant strain. Also, treating an amikacin-intermediate strain with amikacin increased the expression of mexY gene, which has a role in P. aeruginosa antibiotic recalcitrance, while treating the same strain with ferrous and amikacin significantly decreased the expression of mexY gene, which was a promising result. CONCLUSIONS: Our results support the possibility of using ferrous and arginine as an adjuvant to enhance the efficacy of conventional antimicrobial therapy of P. aeruginosa infections.


Assuntos
Fibrose Cística , Infecções por Pseudomonas , Humanos , Antibacterianos/uso terapêutico , Pseudomonas aeruginosa , Amicacina/farmacologia , Nitratos/farmacologia , Nitratos/uso terapêutico , Alginatos/metabolismo , Alginatos/farmacologia , Alginatos/uso terapêutico , Arginina/farmacologia , Arginina/uso terapêutico , Fibrose Cística/microbiologia , Infecções por Pseudomonas/microbiologia , Tobramicina/farmacologia , Ciprofloxacina/farmacologia , Biofilmes , Testes de Sensibilidade Microbiana
10.
Environ Sci Technol ; 57(24): 9064-9074, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37257188

RESUMO

Far-UVC radiation is an emerging tool for combating pathogenic microorganisms in water, but its vulnerability to water matrix components remains unclear. We herein report the critical impacts of nitrate during Far-UVC disinfection of water. Nitrate at environmentally relevant concentrations (0.5-10.0 mg-N L-1) significantly inhibits Escherichia coli inactivation by Far-UVC radiation at 222 nm, via prolonging the "lag phase" of inactivation and reducing the inactivation rate constants by 1.08-2.74 times, while it shows negligible impact on E. coli inactivation by UVC radiation at 254 nm. The inhibitory impact of nitrate on Far-UVC disinfection is attributed to its strong light-shielding effect. Although hydroxyl radicals and reactive nitrogen species are generated from Far-UVC photolysis of nitrate at high concentrations of 10-13 and ∼10-7 M, respectively, those radicals are unable to compensate for the light-shielding effect of nitrate on E. coli inactivation. Moreover, reactive nitrogen species lead to the formation of nitrogenous byproducts, which increase the genotoxicity of the water. The findings advance the fundamental photochemistry and radical chemistry of nitrate at 222 nm and provide useful insights to guide the operation of Far-UVC in treating nitrate-containing water.


Assuntos
Escherichia coli , Nitratos , Escherichia coli/efeitos da radiação , Nitratos/farmacologia , Desinfecção , Fotólise , Raios Ultravioleta
11.
Redox Biol ; 63: 102718, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37120928

RESUMO

A complex interplay of social, lifestyle, and physiological factors contribute to Black Americans having the highest blood pressure (BP) in America. One potential contributor to Black adult's higher BP may be reduced nitric oxide (NO) bioavailability. Therefore, we sought to determine whether augmenting NO bioavailability with acute beetroot juice (BRJ) supplementation would reduce resting BP and cardiovascular reactivity in Black and White adults, but to a greater extent in Black adults. A total of 18 Black and 20 White (∼equal split by biological sex) young adults completed this randomized, placebo-controlled (nitrate (NO3-)-depleted BRJ), crossover design study. We measured heart rate, brachial and central BP, and arterial stiffness (via pulse wave velocity) at rest, during handgrip exercise, and during post-exercise circulatory occlusion. Compared with White adults, Black adults exhibited higher pre-supplementation resting brachial and central BP (Ps ≤0.035; e.g., brachial systolic BP: 116(11) vs. 121(7) mmHg, P = 0.023). Compared with placebo, BRJ (∼12.8 mmol NO3-) reduced resting brachial systolic BP similarly in Black (Δ-4±10 mmHg) and White (Δ-4±7 mmHg) adults (P = 0.029). However, BRJ supplementation reduced BP in males (Ps ≤ 0.020) but not females (Ps ≥ 0.299). Irrespective of race or sex, increases in plasma NO3- were associated with reduced brachial systolic BP (ρ = -0.237, P = 0.042). No other treatment effects were observed for BP or arterial stiffness at rest or during physical stress (i.e., reactivity); Ps ≥ 0.075. Despite young Black adults having higher resting BP, acute BRJ supplementation reduced systolic BP in young Black and White adults by a similar magnitude, an effect that was driven by males.


Assuntos
Hipertensão , Análise de Onda de Pulso , Masculino , Adulto Jovem , Humanos , Pressão Sanguínea , Força da Mão , Brancos , Suplementos Nutricionais , Nitratos/farmacologia , Antioxidantes/farmacologia , Óxido Nítrico/farmacologia
12.
Int J Mol Sci ; 24(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36982308

RESUMO

Legumes associate with Gram-negative soil bacteria called rhizobia, resulting in the formation of a nitrogen-fixing organ, the nodule. Nodules are an important sink for photosynthates for legumes, so these plants have developed a systemic regulation mechanism that controls their optimal number of nodules, the so-called autoregulation of nodulation (AON) pathway, to balance energy costs with the benefits of nitrogen fixation. In addition, soil nitrate inhibits nodulation in a dose-dependent manner, through systemic and local mechanisms. The CLE family of peptides and their receptors are key to tightly controlling these inhibitory responses. In the present study, a functional analysis revealed that PvFER1, PvRALF1, and PvRALF6 act as positive regulators of the nodule number in growth medium containing 0 mM of nitrate but as negative regulators in medium with 2 and 5 mM of nitrate. Furthermore, the effect on nodule number was found to be consistent with changes in the expression levels of genes associated with the AON pathway and with the nitrate-mediated regulation of nodulation (NRN). Collectively, these data suggest that PvFER1, PvRALF1, and PvRALF6 regulate the optimal number of nodules as a function of nitrate availability.


Assuntos
Phaseolus , Nodulação , Nodulação/genética , Nódulos Radiculares de Plantas/metabolismo , Phaseolus/genética , Phaseolus/metabolismo , Nitratos/farmacologia , Nitratos/metabolismo , Peptídeos/metabolismo , Simbiose , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
13.
J Hazard Mater ; 451: 131027, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-36889074

RESUMO

Pathogens in natural water can pose great threat to public health and challenge water quality. In sunlit surface water, dissolved organic matters (DOMs) can inactivate pathogens due to their photochemical activity. However, the photoreactivity of autochthonous DOM derived from different source and their interaction with nitrate on photo-inactivation remained limited understood. In this study, the composition and photoreactivity of DOM extracted from Microcystis (ADOM), submerged aquatic plant (PDOM) and river water (RDOM) were studied. Results revealed that lignin and tannin-like polyphenols and polymeric aromatic compounds negatively correlated with quantum yield of 3DOM*, whilst lignin like molecules positively correlated with •OH generation. ADOM had highest photoinactivation efficiency of E. coli, followed by RDOM and PDOM. Both the photogenerated •OH and low energy 3DOM* could inactivate bacteria damaging cell membrane and causing increase of intracellular reactive species. PDOM with more phenolic or polyphenols compounds not only weaken its photoreactivity, also increase regrowth potential of bacteria after photodisinfection. The presence of nitrate counteracted with autochthonous DOMs on photogeneration of •OH and photodisinfection activity, as well as increased the reactivation rate of PDOM and ADOM, which might be attributed to the increase of survival bacteria and more bioavailable fractions provided in systems.


Assuntos
Desinfecção , Nitratos , Nitratos/farmacologia , Escherichia coli , Lignina , Compostos Orgânicos
14.
Sci Total Environ ; 878: 162848, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36931522

RESUMO

In this study, effect of nitrate-dependent suberization in maize root on cadmium (Cd) uptake and accumulation was investigated. Suberization in maize roots was significantly lower in plants grown with a high nitrate supply compared with low nitrate. This decrease was seen in the total amount of suberin, in which the aliphatic suberin amount was significantly decreased, whereas no difference in aromatic suberin content between different N-treatments. RNA-sequencing showed that suberin biosynthesis genes were upregulated in low nitrate treatment, which correlated well with the increased suberin content. Bioimaging and xylem sap analysis showed that reduced exodermal and endodermal suberization in roots of plants grown under high nitrate promoted radial Cd transport along the crown root. The enhanced suberization in crown roots of plants grown in low nitrate restricted the radial transport of Cd from epidermis to cortex via decreased accessibility to Cd related transporters at the plasmalemma. Also, under low nitrate supply, the Cd transport gene ZmNramp5 was upregulated in the crown root, which may enhance Cd uptake by root tip where exodermis and endodermis were not fully suberized. These results suggest that high nitrate supply enhances Cd uptake and radial transport in maize roots by reducing exodermal and endodermal suberization.


Assuntos
Cádmio , Nitratos , Cádmio/farmacologia , Nitratos/farmacologia , Zea mays , Raízes de Plantas , Transporte Biológico
15.
Bioorg Chem ; 134: 106428, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36893546

RESUMO

Two new series of pyrazole derivatives 10a-f and 11a-f with selective COX-2 inhibition pharmacophore and oxime/nitrate moieties as NO donor moiety were designed, synthesized and tested for anti-inflammatory, cytotoxic activities and NO release. Compounds 10c, 11a, 11e were more selective for COX-2 isozyme (S.I. = 25.95, 22.52 and 21.54 respectively) in comparison to celecoxib (S.I. = 21.41). Regarding anti-cancer activity, all synthesized compounds were screened by the National Cancer Institute (NCI), Bethesda, USA for anticancer activity against 60 human cancer cell lines representing the following cancer types: leukemia, non-small cell lung, colon, CNS, melanoma, ovarian, renal, prostate, and breast cancers. Compounds 10c, 11a, 11e were found to be the most potent inhibitors on breast, ovarian and melanoma cell lines (MCF-7, IGROV1 and SK-MEL-5), compound 11a causing 79 % inhibition in case of MCF-7, 78.80 % inhibition in case of SK-MEL-5 and unexpected cell growth -26.22 % inhibition in case of IGROV1 (IC50 = 3.12, 4.28, 4.13 µM respectively). On the other hand, compounds 10c and 11e showed lower inhibition on the same cell lines with IC50 = 3.58, 4.58, 4.28 µM respectively for 10c, IC50 = 3.43, 4.73, 4.43 µM respectively for 11e. Furthermore, DNA-flow cytometric analysis showed that compound 11a induces cell cycle arrest at G2/M phase leading to cell proliferation inhibition and apoptosis. Additionally, these derivatives examined against F180 fibroblasts to investigate their selectivity indexes. The pyrazole derivative with internal oxime 11a was the most potent compound against most used cell lines especially MCF-7, IGROV1 and SK-MEL-5 (IC50 = 3.12, 4.28, 4.13 µM respectively) with 4.82-fold selectivity towards MCF-7 than F180 fibroblasts. Moreover, oxime derivative 11a showed potent aromatase inhibitory activity (IC50 16.50 µM) when compared with reference compound letrozole (IC50 15.60 µM). All compounds 10a-f and 11a-f released NO in a slow rate (0.73-3.88 %) and the six derivatives 10c, 10e, 11a, 11b, 11c and 11e were the highest NO releasers (3.88, 2.15, 3.27, 2.27, 2.55 and 3.74 % respectively). Herein structure based and ligand based studies were implemented to under stand and evaluate the compounds activity for further in vivo and preclinical studies. Docking mode of final designed compounds with celecoxib (ID: 3LN1) represented that their triazole ring adopted as the core aryl in Y shaped structure. Regarding aromatase enzyme inhibition, docking was carried out with ID: 1 M17. The internal oxime series was more active as anticancer because of their ability to form extra HBs with receptor cleft.


Assuntos
Antineoplásicos , Neoplasias da Mama , Melanoma , Masculino , Humanos , Inibidores da Aromatase/farmacologia , Celecoxib/farmacologia , Ciclo-Oxigenase 2/metabolismo , Nitratos/farmacologia , Aromatase/metabolismo , Doadores de Óxido Nítrico/farmacologia , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , Anti-Inflamatórios/farmacologia , Antineoplásicos/química , Proliferação de Células , Estrutura Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Desenho de Fármacos
16.
Am J Physiol Regul Integr Comp Physiol ; 324(3): R317-R328, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36622081

RESUMO

Independent supplementation with nitrate (NIT) and resveratrol (RSV) enriches various aspects of mitochondrial biology in key metabolic tissues. Although RSV is known to activate Sirt1 and initiate mitochondrial biogenesis, the metabolic benefits elicited by dietary nitrate appear to be dependent on 5'-adenosine monophosphate-activated protein kinase (AMPK)-mediated signaling events, a process also linked to the activation of Sirt1. Although the benefits of individual supplementation with these compounds have been characterized, it is unknown if co-supplementation may produce superior metabolic adaptations. Thus, we aimed to determine if treatment with combined +NIT and +RSV (+RN) could additively alter metabolic adaptations in the presence of a high-fat diet (HFD). Both +RSV and +NIT improved glucose tolerance compared with HFD (P < 0.05); however, this response was attenuated following combined +RN supplementation. Within skeletal muscle, all supplements increased mitochondrial ADP sensitivity compared with HFD (P < 0.05), without altering mitochondrial content. Although +RSV and +NIT decreased hepatic lipid deposition compared with HFD (P < 0.05), this effect was abolished with +RN, which aligned with significant reductions in Sirt1 protein content (P < 0.05) after combined treatment, in the absence of changes to mitochondrial content or function. Within epididymal white adipose tissue (eWAT), all supplements reduced crown-like structure accumulation compared with HFD (P < 0.0001) and mitochondrial reactive oxygen species (ROS) emission (P < 0.05), alongside reduced adipocyte cross-sectional area (CSA) (P < 0.05), with the greatest effect observed after +RN treatment (P = 0.0001). Although the present data suggest additive changes in adipose tissue metabolism after +RN treatment, concomitant impairments in hepatic lipid homeostasis appear to prevent improvements in whole body glucose homeostasis observed with independent treatment, which may be Sirt1 dependent.


Assuntos
Nitratos , Sirtuína 1 , Camundongos , Animais , Masculino , Resveratrol/farmacologia , Nitratos/farmacologia , Sirtuína 1/metabolismo , Suplementos Nutricionais , Dieta Hiperlipídica , Proteínas Quinases Ativadas por AMP/metabolismo , Glucose/metabolismo , Lipídeos
17.
Plant Cell ; 35(2): 776-794, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36440970

RESUMO

Legumes acquire fixed nitrogen (N) from the soil and through endosymbiotic association with diazotrophic bacteria. However, establishing and maintaining N2-fixing nodules are expensive for the host plant, relative to taking up N from the soil. Therefore, plants suppress symbiosis when N is plentiful and enhance symbiosis when N is sparse. Here, we show that the nitrate transporter MtNRT2.1 is required for optimal nodule establishment in Medicago truncatula under low-nitrate conditions and the repression of nodulation under high-nitrate conditions. The NIN-like protein (NLP) MtNLP1 is required for MtNRT2.1 expression and regulation of nitrate uptake/transport under low- and high-nitrate conditions. Under low nitrate, the gene encoding the C-terminally encoded peptide (CEP) MtCEP1 was more highly expressed, and the exogenous application of MtCEP1 systemically promoted MtNRT2.1 expression in a compact root architecture 2 (MtCRA2)-dependent manner. The enhancement of nodulation by MtCEP1 and nitrate uptake were both impaired in the Mtnrt2.1 mutant under low nitrate. Our study demonstrates that nitrate uptake by MtNRT2.1 differentially affects nodulation at low- and high-nitrate conditions through the actions of MtCEP1 and MtNLP1.


Assuntos
Medicago truncatula , Nitratos , Regulação da Expressão Gênica de Plantas , Medicago truncatula/metabolismo , Nitratos/farmacologia , Nitratos/metabolismo , Peptídeos/genética , Peptídeos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nodulação/genética , Nódulos Radiculares de Plantas/genética , Nódulos Radiculares de Plantas/metabolismo , Simbiose/fisiologia
18.
Bioresour Technol ; 369: 128401, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36442600

RESUMO

The effect of ferric iron (Fe(Ш)) on the performance of heterotrophic solid-phase denitrification (SPD) using biodegradable polymer composite as the electron donor was investigated. The results of continuous batch experiments showed that the addition of over 10 mg/L Fe(Ш) significantly inhibited nitrate removal and led to the accumulation of nitrite. The addition of Fe(Ш) reduced the microbial community diversity and shifted the community dominated by complete denitrifiers (e.g. Thauera) to that dominated by incomplete denitrifiers (e.g. Thermomonas, Stenotrophomonas and Sphingomonas). The predicted analysis of microbial function by PICRUSt2 indicated that the relative abundance of denitrifying genes, including napA/B, nirS and nosZ, were remarkably reduced in the Fe(Ш) groups comparing with the control group. In addition, Fe(Ш) inhibited the genes related to the generation of electron carriers, NADH and FADH2, in TCA cycle and glycolysis processes, which could result in a lower carbon utilization efficiency for microbial denitrification.


Assuntos
Desnitrificação , Nitratos , Nitratos/farmacologia , Nitratos/metabolismo , Processos Heterotróficos , Redes e Vias Metabólicas , Ferro/farmacologia , Nitrogênio/metabolismo , Reatores Biológicos
19.
Eur J Appl Physiol ; 123(1): 91-102, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36175576

RESUMO

PURPOSE: To determine the effects of dietary nitrate (NO3-) supplementation on physiological responses, cognitive function, and performance during heavy load carriage in military cadets. METHODS: Ten healthy males (81.0 ± 6.5 kg; 180.0 ± 4.5 cm; 56.2 ± 3.7 ml·kg·min-1 VO2max) consumed 140 mL·d-1 of beetroot juice (BRJ; 12.8 mmol NO3-) or placebo (PL) for six d preceding an exercise trial, which consisted of 45 min of load carriage (55% body mass) at 4.83 km·h-1 and 1.5% grade, followed by a 1.6-km time-trial (TT) at 4% grade. Gas exchange, heart rate, and perceptual responses were assessed during constant-load exercise and the TT. Cognitive function was assessed immediately prior to, during, and post-exercise via the psychomotor vigilance test (PVT). RESULTS: Post-TT HR (188 ± 7.1 vs. 185 ± 7.4; d = 0.40; p = 0.03), mean tidal volume (2.15 ± 0.27 vs. 2.04 ± 0.23; p = 0.02; d = 0.47), and performance (770.9 ± 78.2 s vs. 809.8 ± 61.4 s; p = 0.03; d = 0.63) were increased during the TT with BRJ versus PL. There were no effects of BRJ on constant-load gas exchange or perceptual responses, and cognitive function was unchanged at all time points. CONCLUSION: BRJ supplementation improves heavy load carriage performance in military cadets possibly as a result of attenuated respiratory muscle fatigue, rather than enhanced exercise economy.


Assuntos
Beta vulgaris , Militares , Masculino , Humanos , Nitratos/farmacologia , Suplementos Nutricionais , Exercício Físico , Antioxidantes , Método Duplo-Cego , Estudos Cross-Over
20.
Eur Rev Med Pharmacol Sci ; 26(20): 7371-7378, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36314307

RESUMO

OBJECTIVE: Acetaminophen (APAP) is one of the most commonly used analgesics and antipyretics. It causes serious liver damage when taken in large quantities by adults or children. Also, 6-shogaol is an active compound obtained from ginger with anti-inflammatory and antioxidant properties. This study aimed at examining the therapeutic effect of 6-shogaol in APAP-induced hepatotoxicity. MATERIALS AND METHODS: The mice were separated into five groups. After the mice were sacrificed, the levels of alanine aminotransferase (ALT), aspartate transaminase (AST), and alkaline phosphatase (ALP) in the blood, glutathione (GSH) level in the liver tissue homogenate, and levels of induced nitrite oxide synthetase (INOS) and total nitrite/nitrate were measured by spectrophotometric methods. RESULTS: APAP administration significantly increased the serum levels of ALT, AST, and ALP, INOS activity in liver tissue, and total nitrite/nitrate levels compared with control and significantly decreased GSH levels. After APAP toxicity, 6-shogaol and N-acetylcysteine (NAC) administration significantly decreased the levels of ALT, AST, INOS, and total nitrite/nitrate levels and significantly increased GSH levels compared with control. Also, 6-shogaol was found to be better than NAC in increasing the GSH level. CONCLUSIONS: The study showed that 6-shogaol might have an early therapeutic effect on APAP-induced liver damage.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Hepatopatias , Camundongos , Animais , Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Nitritos/farmacologia , Nitratos/farmacologia , Aspartato Aminotransferases , Alanina Transaminase , Acetilcisteína/farmacologia , Fígado , Glutationa
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