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1.
Braz J Biol ; 84: e279415, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39230076

RESUMEN

Salinity limits the growth and productivity of crops, to reverse these effects, natural pigments with antioxidant bioactivity can be studied, such as turmeric (Curcuma longa L.) and paprika (Capsicum annum L.). Therefore, it aimed to evaluate turmeric and paprika as possible saline stress attenuators and biostimulants during germination and initial development of smooth lettuce seedlings. In the laboratory, the seeds were treated for 1 hour with a solution of paprika and turmeric at doses 0 (negative control), 1, 2, 3 and 4 g L-1, and placed on a substrate with saline solution of sodium chloride 4 g L-1 (-0,4 Mpa), and a positive control, composed of dry seeds arranged in a substrate moistened with distilled water. Physiological quality analysis were carried out, and for the dose that showed the best result (4 g L-1), the treated seeds were grown in a greenhouse, and received weekly applications via foliar with a 4 g L-1 solution for turmeric and paprika. After the crop cycle, morphometric analyzes were performed. The turmeric and paprika solutions were analyzed by High-Performance Liquid Chromatography (HPLC) to identify the presence of bioactive substances. The turmeric doses were not efficient in overcoming the effects of salinity on seeds and seedlings, which was attributed to the low solubility of turmeric in water. Paprika, although it did not provide the biostimulant effect, was efficient in attenuating the effects of excess salt, at a concentration of 4 g L-1, promoting increases in physiological quality. In HPLC, a very low signal response was noted in relation to samples composed of turmeric and paprika solutions, indicating a low percentage of soluble compounds, which compromises bioactivity, and leads to the need for further analyses using surfactants and/or other solvents with which there is greater affinity.


Asunto(s)
Antioxidantes , Curcuma , Germinación , Antioxidantes/farmacología , Curcuma/química , Germinación/efectos de los fármacos , Germinación/fisiología , Lactuca/efectos de los fármacos , Lactuca/química , Lactuca/crecimiento & desarrollo , Cromatografía Líquida de Alta Presión , Salinidad , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/química , Semillas/química , Semillas/efectos de los fármacos , Semillas/crecimiento & desarrollo , Extractos Vegetales/farmacología , Extractos Vegetales/química , Cloruro de Sodio/farmacología
2.
Arch Microbiol ; 206(9): 377, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39141120

RESUMEN

The high content and quality of protein in Andean legumes make them valuable for producing protein hydrolysates using proteases from bacteria isolated from extreme environments. This study aimed to carry out a single-step purification of a haloprotease from Micrococcus sp. PC7 isolated from Peru salterns. In addition, characterize and apply the enzyme for the production of bioactive protein hydrolysates from underutilized Andean legumes. The PC7 protease was fully purified using only tangential flow filtration (TFF) and exhibited maximum activity at pH 7.5 and 40 °C. It was characterized as a serine protease with an estimated molecular weight of 130 kDa. PC7 activity was enhanced by Cu2+ (1.7-fold) and remained active in the presence of most surfactants and acetonitrile. Furthermore, it stayed completely active up to 6% NaCl and kept Ì´ 60% of its activity up to 8%. The protease maintained over 50% of its activity at 25 °C and 40 °C and over 70% at pH from 6 to 10 for up to 24 h. The determined Km and Vmax were 0.1098 mg mL-1 and 273.7 U mL-1, respectively. PC7 protease hydrolyzed 43%, 22% and 11% of the Lupinus mutabilis, Phaseolus lunatus and Erythrina edulis protein concentrates, respectively. Likewise, the hydrolysates from Lupinus mutabilis and Erythrina edulis presented the maximum antioxidant and antihypertensive activities, respectively. Our results demonstrated the feasibility of a simple purification step for the PC7 protease and its potential to be applied in industrial and biotechnological processes. Bioactive protein hydrolysates produced from Andean legumes may lead to the development of nutraceuticals and functional foods contributing to address some United Nations Sustainable Development Goals (SDGs).


Asunto(s)
Fabaceae , Micrococcus , Hidrolisados de Proteína , Micrococcus/metabolismo , Micrococcus/enzimología , Concentración de Iones de Hidrógeno , Hidrolisados de Proteína/química , Hidrolisados de Proteína/metabolismo , Peso Molecular , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/aislamiento & purificación , Perú , Temperatura , Serina Proteasas/metabolismo , Serina Proteasas/aislamiento & purificación , Serina Proteasas/química , Estabilidad de Enzimas , Cloruro de Sodio/metabolismo , Cloruro de Sodio/farmacología , Hidrólisis , Cinética
3.
Food Res Int ; 192: 114744, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39147550

RESUMEN

The use of natural and sustainable additives, that are less aggressive to the environment, is a trend in the food industry. Rhamnolipids (RL) biosurfactants have shown potential for controlling food pathogens however, due to the presence of free carboxyl groups, the pH and ionic strength may influence the properties of such surfactants. In this study, we describe the antimicrobial activity of RL under different pH values and NaCl concentrations, towards both planktonic and biofilms of Listeria monocytogenes. RL were effective at pH 5.0 and the addition of 5 % NaCl improved the bactericidal efficacy for planktonic and sessile cells. The effect of NaCl was more pronounced at pH above 6 showing a significant increase in RL antimicrobial activity. At pH 7.0 planktonic population was eradicated by RL only when salt was present whereas biofilm viability was decreased by 5 log with MBIC varying from > 2500.0 mg/L (RL) to 39.0 mg/L (RL + 5 % NaCl). Larger vesicular and lamellar RL self-assembly structures were predominant when NaCl was present, suggesting their association with the antimicrobial activity observed. The pH and ionic strength of the medium are important parameters to be considered for the development of RL-based strategies to control L. monocytogenes.


Asunto(s)
Biopelículas , Glucolípidos , Listeria monocytogenes , Cloruro de Sodio , Listeria monocytogenes/efectos de los fármacos , Listeria monocytogenes/crecimiento & desarrollo , Concentración de Iones de Hidrógeno , Glucolípidos/farmacología , Glucolípidos/química , Cloruro de Sodio/farmacología , Cloruro de Sodio/química , Concentración Osmolar , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Antibacterianos/farmacología , Tensoactivos/farmacología , Tensoactivos/química , Microbiología de Alimentos , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos
4.
Am J Bot ; 111(7): e16373, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39010314

RESUMEN

PREMISE: Salt tolerance has rarely been investigated regionally in the neotropics and even more rarely in Orchidaceae, one of the largest families. Therefore, investigating local adaptation to salt spray and its physiological basis in Epidendrum fulgens, a neotropical orchid species, brings important new insights. METHODS: We assessed the degree of salt tolerance in E. fulgens by testing whether coastal populations are more tolerant to salt, which could point to local adaptation. To understand the physiological basis of such salt tolerance, we exposed wild-collected individuals to salt spray for 60 days, then measured leaf expansion, osmotic potential, sodium leaf concentration, chlorophyll leaf index, chlorophyll fluorescence, relative growth rate, and pressure-volume curves. RESULTS: There is no local adaptation to salt spray since both inland and coastal plants have a high tolerance to salt stress. This tolerance is explained by the ability to tolerate high concentrations of salt in leaf tissues, which is related to the high succulence displayed by this species. CONCLUSIONS: We showed an unprecedented salt tolerance level for an orchid species, highlighting our limited knowledge of that trait beyond the traditional studied groups. Another interesting finding is that salt tolerance in E. fulgens is linked to succulence, is widespread, and is not the result of local adaptation. We suggest that E. fulgens and its allied species could be an interesting group to explore the evolution of important traits related to tolerance to salt stress, like succulence.


Asunto(s)
Adaptación Fisiológica , Orchidaceae , Hojas de la Planta , Tolerancia a la Sal , Orchidaceae/fisiología , Orchidaceae/efectos de los fármacos , Hojas de la Planta/fisiología , Hojas de la Planta/efectos de los fármacos , Cloruro de Sodio/farmacología , Clorofila/metabolismo , Sodio/metabolismo , Clima Tropical
5.
BMC Biol ; 22(1): 63, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38481317

RESUMEN

BACKGROUND: Obligate blood-feeding insects obtain the nutrients and water necessary to ensure survival from the vertebrate blood. The internal taste sensilla, situated in the pharynx, evaluate the suitability of the ingested food. Here, through multiple approaches, we characterized the pharyngeal organ (PO) of the hematophagous kissing bug Rhodnius prolixus to determine its role in food assessment. The PO, located antero-dorsally in the pharynx, comprises eight taste sensilla that become bathed with the incoming blood. RESULTS: We showed that these taste sensilla house gustatory receptor neurons projecting their axons through the labral nerves to reach the subesophageal zone in the brain. We found that these neurons are electrically activated by relevant appetitive and aversive gustatory stimuli such as NaCl, ATP, and caffeine. Using RNA-Seq, we examined the expression of sensory-related gene families in the PO. We identified gustatory receptors, ionotropic receptors, transient receptor potential channels, pickpocket channels, opsins, takeouts, neuropeptide precursors, neuropeptide receptors, and biogenic amine receptors. RNA interference assays demonstrated that the salt-related pickpocket channel Rproppk014276 is required during feeding of an appetitive solution of NaCl and ATP. CONCLUSIONS: We provide evidence of the role of the pharyngeal organ in food evaluation. This work shows a comprehensive characterization of a pharyngeal taste organ in a hematophagous insect.


Asunto(s)
Cloruro de Sodio , Gusto , Animales , Gusto/fisiología , Cloruro de Sodio/farmacología , Faringe , Insectos , Adenosina Trifosfato
6.
Plant Physiol Biochem ; 207: 108372, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38228015

RESUMEN

Castor (Ricinus communis) is a relevant industrial oilseed feedstock for many industrial applications, being globally mainly cultivated by smallholder farmers in semiarid areas, where abiotic stresses predominate. Therefore, susceptible to generating reactive oxygen species (ROS) and subsequent oxidative stress, compromising cell metabolism upon seed imbibition and germination, seedling and crop establishment, and yield. The present study evaluated the consequences of water restriction by Polyethylene glycol (PEG) and Sodium chloride (NaCl) on cell cycle and metabolism reactivation on germinability, seedling growth, and vigor parameters in 2 commercial castor genotypes (Nordestina and Paraguaçu). PEG water restriction inhibited germination completely at -0.23 MPa or higher, presumably due to reduced oxygen availability. The restrictive effects of NaCl saline stress on germination were observed only from -0.46 MPa onwards, affecting dry mass accumulation and the production of normal seedlings. In general, superoxide dismutase (SOD) activity increased in NaCl -0.23 MPa, whereas its modulation during the onset of imbibition (24h) seemed to depend on its initial levels in dry seeds in a genotype-specific manner, therefore, resulting in the higher stress tolerance of Nordestina compared to Paraguaçu. Overall, results show that Castor germination and seedling development are more sensitive to the restrictive effects of PEG than NaCl at similar osmotic potentials, contributing to a better understanding of the responses to water restriction stresses by different Castor genotypes. Ultimately, SOD may constitute a potential marker for characterizing castor genotypes in stressful situations during germination, early seedling, and crop establishment, and a target for breeding for Castor-improved stress tolerance.


Asunto(s)
Ricinus communis , Plantones , Plantones/metabolismo , Cloruro de Sodio/farmacología , Cloruro de Sodio/metabolismo , Ricinus communis/genética , Polietilenglicoles/farmacología , Polietilenglicoles/metabolismo , Germinación , Ciclo Celular , Semillas/metabolismo , Agua/metabolismo , Superóxido Dismutasa/metabolismo
7.
An Acad Bras Cienc ; 95(3): e20230014, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37878911

RESUMEN

Microbial proteases are one of the most demanding enzymes for various industries with diverse applications in food, pharmaceutics, and textile industries to name the few. An extracellular alkaline metalloprotease was produced and purified from moderate halophilic bacterial strain, Bacillus cereus TS2, with some unique characteristics required for various industrial applications. The protease was produced in basal medium supplemented with casein and was partially purified by ion exchange chromatography followed by ammonium sulphate precipitation. The alkaline metalloprotease has molecular weight of 35 kDa with specific activity of 535.4 µM/min/mg. It can work at wide range of pH from 3 to 12, while showing optimum activity at pH 10. Similarly, the alkaline metalloprotease is stable till the temperature of 80 °C and works at wide range of temperature from 20 to 90 °C with optimum activity at 60 °C. The turnover rate increases in the presence of NaCl and Co+2 with k cat/KM of 1.42 × 103 and 1.27 × 103 s-1.M-1 respectively, while without NaCl and Co+2 it has a value of 7.58× 102. The alkaline metalloprotease was relatively resistant to thermal and solvent mediated denaturation. Applications revealed that the metalloprotease was efficient to remove hair from goat skin, remove blood stains and degrade milk, thus can be a potential candidate for leather, detergent, and food industry.


Asunto(s)
Bacillus cereus , Cloruro de Sodio , Cloruro de Sodio/farmacología , Metaloproteasas/química , Péptido Hidrolasas , Temperatura , Concentración de Iones de Hidrógeno
8.
Acta Cir Bras ; 38: e381723, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37098927

RESUMEN

PURPOSE: The effects of hesperidin application on the wound caused by esophageal burns were investigated in this study. METHODS: Wistar albino rats were divided into three groups: Control group: only 1 mL of 0.09% NaCl was administered i.p. for 28 days; Burn group: An alkaline esophageal burn model was created with 0.2 mL of 25% NaOH orally by gavage-1 mL of 0.09% NaCl was administered i.p. for 28 days; Burn+Hesperidin group: 1 mL of 50 mL/kg of hesperidin was given i.p. for 28 days to rats after burn injury. Blood samples were collected for biochemical analysis. Esophagus samples were processed for histochemical staining and immunohistochemistry. RESULTS: Malondialdehyde (MDA) and myeloperoxidase (MPO) levels were significantly increased in Burn group. Glutathione (GSH) content and histological scores of epithelialization, collagen formation, neovascularization was decreased. After hesperidin treatment, these values were significantly improved in the Burn+Hesperidin group. In the Burn group, epithelial cells and muscular layers were degenerated. Hesperidin treatment restored these pathologies in Burn+Hesperidin group. Ki-67 and caspase-3 expressions were mainly negative in control group; however, the expression was increased in the Burn group. In the Burn+Hesperidin group, Ki-67 and caspase-3 immune activities were reduced. CONCLUSIONS: Hesperidin dosage and application methods can be developed as an alternative treatment for burn healing and treatment.


Asunto(s)
Hesperidina , Animales , Ratas , Hesperidina/farmacología , Antígeno Ki-67 , Caspasa 3 , Cloruro de Sodio/farmacología , Ratas Wistar , Cicatrización de Heridas , Glutatión/metabolismo , Esófago/lesiones , Esófago/metabolismo , Esófago/patología
9.
Chem Senses ; 482023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37086194

RESUMEN

The spontaneously hypertensive rats (SHRs) have enhanced palatability for NaCl taste as measured by the increased number of hedonic versus aversive responses to intraoral infusion (1 mL/1 min) of 0.3 M NaCl, in a taste reactivity test in euhydrated condition or after 24 h of water deprivation + 2 h of partial rehydration (WD-PR). SHRs also ingested more sucrose than normotensive rats, without differences in quinine hydrochloride intake. Here, we investigated the palatability of SHRs (n = 8-10) and normotensive Holtzman rats (n = 8-10) to sucrose and quinine sulphate infused intraorally in the same conditions that NaCl palatability was increased in SHRs. SHRs had similar number of hedonic responses to 2% sucrose in euhydrated condition (95 ± 19) or after WD-PR (142 ± 25), responses increased when compared with normotensive rats in euhydrated condition (13 ± 3) or after WD-PR (21 ± 6). SHRs also showed increased number of aversive responses to 1.4 mM quinine sulphate compared with normotensive rats, whether in euhydrated condition (86 ± 6, vs. normotensive: 54 ± 7) or after WD-PR (89 ± 9, vs. normotensive: 40 ± 9). The results suggest that similar to NaCl taste, sweet taste responses are increased in SHRs and resistant to challenges in bodily fluid balance. They also showed a more intense aversive response in SHRs to bitter taste compared with normotensives. This suggests that the enhanced response of SHRs to taste rewards does not correspond to a decreased response to a typical aversive taste.


Asunto(s)
Quinina , Cloruro de Sodio , Ratas , Animales , Ratas Endogámicas SHR , Cloruro de Sodio/farmacología , Quinina/farmacología , Gusto/fisiología , Ratas Sprague-Dawley , Sacarosa/farmacología
10.
J Food Prot ; 86(5): 100086, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37001815

RESUMEN

Mild cooking thermal treatments, like sous-vide, can compromise ground meat entrees such as meatballs with chipotle sauce, especially when salt levels are reduced during its preparation. Listeria monocytogenes is a thermoresistant pathogen that can be in ready-to-eat food. On the other hand, nisin, due to its thermal stability, can be a good alternative to aid on the thermal inactivation of L. monocytogenes and ensure meat safety. The objective was to optimize the amount of nisin and salt concentrations to thermally inactivate L. monocytogenes during the sous-vide cooking of ground beef marinated in chipotle sauce, and to generate a predictive model. A four-strain cocktail was prepared and inoculated in ground beef in combination (3:2) with chipotle sauce added with nisin (0-150 IU) and salt (0-2%). After that, meat samples were sous-vide cooked at different temperatures, nisin, and salt concentrations, established by a central composite design. Depending on the levels of these factors, D-values ranged from 49.71 to 0.27 min. A predictive model (p < 0.05) was obtained by response surface, which described that D-values variation was explained by the linear effects of the three factors, the interaction between nisin and temperature, and the quadratic effects of salt and temperature. It was also observed that nisin presented a bactericidal effect while salt presented a protective effect during the thermal inactivation of L. monocytogenes. Adding 120 IU of nisin and 0.4% of salt to the meat product at 63°C temperature can help to ensure food safety by making L. monocytogenes cells more sensitive to the lethal effect of heat. The model developed in this study can be used by food processors for planning and designing effective levels of salt and nisin to thermally inactivate L. monocytogenes in ground beef products marinated with chipotle sauce to ensure their safety.


Asunto(s)
Listeria monocytogenes , Productos de la Carne , Nisina , Animales , Bovinos , Cloruro de Sodio/farmacología , Nisina/farmacología , Carne , Microbiología de Alimentos
11.
Hypertension ; 80(4): 872-881, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36752103

RESUMEN

BACKGROUND: Salt-sensitive hypertension in humans and experimental models is associated with higher plasma and cerebrospinal fluid sodium chloride (NaCl) concentrations. Changes in extracellular NaCl concentrations are sensed by specialized neurons in the organum vasculosum of the lamina terminalis (OVLT). Stimulation of OVLT neurons increases sympathetic nerve activity (SNA) and arterial blood pressure (ABP), whereas chronic activation produces hypertension. Therefore, the present study tested whether OVLT neuronal activity was elevated and contributed to SNA and ABP in salt-sensitive hypertension. METHODS: Male Dahl salt-sensitive (Dahl S) and Dahl salt-resistant (Dahl R) rats were fed 0.1% or 4.0% NaCl diets for 3 to 4 weeks and used for single-unit recordings of OVLT neurons or simultaneous recording of multiple sympathetic nerves during pharmacological inhibition of the OVLT. RESULTS: Plasma and cerebrospinal fluid Na+ and Cl- concentrations were higher in Dahl S rats fed 4% versus 0.1% or Dahl R rats fed either diet. In vivo single-unit recordings revealed a significantly higher discharge of NaCl-responsive OVLT neurons in Dahl S rats fed 4% versus 0.1% or Dahl R rats. Interestingly, intracarotid infusion of hypertonic NaCl evoked greater increases in OVLT neuronal discharge of Dahl S versus Dahl R rats regardless of NaCl diet. The activity of non-NaCl-responsive OVLT neurons was not different across strain or diets. Finally, inhibition of OVLT neurons by local injection of the gamma-aminobutyric acid agonist muscimol produced a greater decrease in renal SNA, splanchnic SNA, and ABP of Dahl S rats fed 4% versus 0.1% or Dahl R rats. CONCLUSIONS: A high salt diet activates NaCl-responsive OVLT neurons to increase SNA and ABP in salt-sensitive hypertension.


Asunto(s)
Hipertensión , Organum Vasculosum , Ratas , Animales , Humanos , Masculino , Cloruro de Sodio/farmacología , Ratas Sprague-Dawley , Alta del Paciente , Ratas Endogámicas Dahl , Cloruro de Sodio Dietético , Hipotálamo , Presión Sanguínea/fisiología
12.
Pest Manag Sci ; 79(6): 2255-2263, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36775861

RESUMEN

BACKGROUND: Freshwater organisms are facing increasing salinity levels, not only due to natural environmental processes, but also human activities, which can cause several physiological adaptations to osmotic stress. Additionally, these organisms might also have to deal with contamination by microbial insecticides. Our main goal was to use Chironomus xanthus to assess the chronic effects of increasing the salinity and commercial formulations of the microbial insecticides based on Bacillus thuringiensis subs. kurstaki (Btk) and Beauveria bassiana (Bb) as active ingredients, respectively. RESULTS: A significant interaction of growth was observed between the biopesticide based on Bb and NaCl on the larvae of C. xanthus. Single exposure to NaCl and each one of the formulations demonstrated deleterious impacts not only on larval development, but also on the emergence success and emergence time of this nontarget insect, with potential consequences for freshwater ecosystems due to cascading effects. CONCLUSION: The chronic effects induced by both bioinsecticides show that these formulations can have environmental impacts on nontarget freshwater insects. © 2023 Society of Chemical Industry.


Asunto(s)
Bacillus thuringiensis , Beauveria , Chironomidae , Insecticidas , Animales , Humanos , Insecticidas/farmacología , Chironomidae/fisiología , Cloruro de Sodio/farmacología , Ecosistema , Insectos , Larva
13.
Braz J Biol ; 84: e265825, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36700585

RESUMEN

The advancements in the cell culture studies have led to the development of regenerative medicine concept. The aim of this study is to compare the effectiveness of some washing solutions, including phosphate buffered saline (PBS), sodium chloride (NaCl), and ringer's lactate (RL) on the rate of detachment and confluency in fibroblast and osteoblast cell culture. Baby Hamster Kidney 21 clone 13 (BHK21/C13) fibroblast cells and 7F2 osteoblast were cultured on T25 flasks for 3-4 days. Three treatment groups were classified on the basis of different washing solutions used in the moment before trypsinization: PBS, 0.9% NaCl, and RL. Each group was measured for the detachment rate and cell confluence. The measurement was done in 2 passage numbers. The use of PBS, NaCl, and RL washing solution showed that detachment time was less than 5 minutes for the fibroblasts and 3 minutes for the osteoblasts. There was a significant difference in the rate of fibroblast cell detachment (p=0.006) and osteoblast (p=0.016). The capability of fibroblasts and osteoblasts to achieve a confluence of 106 cells/well on the first and second measurements was almost the same between the washing solution groups. The use of physiological 0.9% NaCl solution as a washing solution in fibroblast and osteoblast cell culture has almost the same effectiveness as PBS to help accelerate cell detachment in less than 5 minutes without influencing the capability of cells to proliferate.


Asunto(s)
Técnicas de Cultivo de Célula , Solución Salina , Cloruro de Sodio , Humanos , Fibroblastos , Soluciones Isotónicas/farmacología , Osteoblastos , Lactato de Ringer , Cloruro de Sodio/farmacología
14.
Exp Physiol ; 108(3): 361-370, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36715005

RESUMEN

NEW FINDINGS: What is the central question of this study? Is the cardiovascular phenotype of high blood pressure observed in rats salt loaded with 2% NaCl in drinking solution a blood volume-dependent hypertension? What is the main finding and its importance? Animals exposed to 2% NaCl drinking solution develop hypertension, with dominance of sympathetic outflow and high [Na+ ] in the cerebrospinal fluid, but without changes in the blood volume. The phenotype of salt-dependent hypertension might be related to accumulation of [Na+ ] in the cerebrospinal fluid, which makes it an interesting animal model in which to study the neuronal pathways involved in control of the circulation in osmotic challenge conditions. ABSTRACT: Evidence suggests that hypertension induced by high salt intake is correlated with an autonomic imbalance that favours sympathetic hyperactivity and an increase in vascular resistance, indicating a neurogenic component to this pathology. Although there are several animal models in which to study salt-induced hypertension with prolonged exposure to a high-sodium diet, here we sought to investigate whether the increase in arterial blood pressure of rats subjected to a short exposure to high salt, with 2% NaCl drinking solution instead of water, relies on changes in the circulating blood volume. Male Wistar rats were divided randomly into three groups: euhydrated (EU, n = 10), salt loaded (SL, n = 13) and water deprived (WD, n = 6). The SL rats exhibited a significant increase in mean arterial blood pressure, with a large low-frequency component of systolic arterial blood pressure variability, when compared with the EU group. Circulating blood volume did not differ between SL and EU rats, but it was lower in WD rats. Compared with EU rats, the [Na+ ] in cerebrospinal fluid was higher in SL rats and similar in magnitude to the WD rats. Plasma [Na+ ] did not differ between SL and EU rats, but it was higher in WD rats. Collectively, our data suggest that the hypertension induced by a short exposure to high salt intake closely resembles a neurogenic mechanism, but not a blood volume-dependent mechanism, with cumulative [Na+ ] in the cerebrospinal fluid that could be associated with changes in the neurochemistry of autonomic nuclei, which are highly susceptible to osmotic stress related to high salt consumption.


Asunto(s)
Hipertensión , Cloruro de Sodio Dietético , Ratas , Masculino , Animales , Cloruro de Sodio Dietético/efectos adversos , Cloruro de Sodio/farmacología , Ratas Wistar , Presión Sanguínea/fisiología , Sodio , Volumen Sanguíneo , Fenotipo
15.
PeerJ ; 11: e14624, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36647445

RESUMEN

Salt stress is one of the most severe abiotic stresses affecting plant growth and development. The application of silicon (Si) is an alternative that can increase the tolerance of plants to various types of biotic and abiotic stresses. The objective was to evaluate salt stress's effect in vitro and Si's mitigation potential on Aechmea blanchetiana plants. For this purpose, plants already established in vitro were transferred to a culture medium with 0 or 14 µM of Si (CaSiO3). After growth for 30 days, a stationary liquid medium containing different concentrations of NaCl (0, 100, 200, or 300 µM) was added to the flasks. Anatomical and physiological analyses were performed after growth for 45 days. The plants cultivated with excess NaCl presented reduced root diameter and effective photochemical quantum yield of photosystem II (PSII) (ΦPSII) and increased non-photochemical dissipation of fluorescence (qN). Plants that grew with the presence of Si also had greater content of photosynthetic pigments and activity of the enzymes of the antioxidant system, as well as higher values of maximum quantum yield of PSII (FV/FM), photochemical dissipation coefficient of fluorescence (qP) and fresh weight bioaccumulation of roots and shoots. The anatomical, physiological and biochemical responses, and growth induced by Si mitigated the effect of salt stress on the A. blanchetiana plants cultivated in vitro, which can be partly explained by the tolerance of this species to grow in sandbank (Restinga) areas.


Asunto(s)
Bromeliaceae , Cloruro de Sodio , Cloruro de Sodio/farmacología , Silicio/farmacología , Bromeliaceae/metabolismo , Fotosíntesis , Complejo de Proteína del Fotosistema II/metabolismo
16.
Protoplasma ; 260(2): 467-482, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35788779

RESUMEN

Plants adjust their complex molecular, biochemical, and metabolic processes to overcome salt stress. Here, we investigated the proteomic and epigenetic alterations involved in the morphophysiological responses of Pfaffia glomerata, a medicinal plant, to salt stress and the demethylating agent 5-azacytidine (5-azaC). Moreover, we investigated how these changes affected the biosynthesis of 20-hydroxyecdysone (20-E), a pharmacologically important specialized metabolite. Plants were cultivated in vitro for 40 days in Murashige and Skoog medium supplemented with NaCl (50 mM), 5-azaC (25 µM), and NaCl + 5-azaC. Compared with the control (medium only), the treatments reduced growth, photosynthetic rates, and photosynthetic pigment content, with increase in sucrose, total amino acids, and proline contents, but a reduction in starch and protein. Comparative proteomic analysis revealed 282 common differentially accumulated proteins involved in 87 metabolic pathways, most of them related to amino acid and carbohydrate metabolism, and specialized metabolism. 5-azaC and NaCl + 5-azaC lowered global DNA methylation levels and 20-E content, suggesting that 20-E biosynthesis may be regulated by epigenetic mechanisms. Moreover, downregulation of a key protein in jasmonate biosynthesis indicates the fundamental role of this hormone in the 20-E biosynthesis. Taken together, our results highlight possible regulatory proteins and epigenetic changes related to salt stress tolerance and 20-E biosynthesis in P. glomerata, paving the way for future studies of the mechanisms involved in this regulation.


Asunto(s)
Amaranthaceae , Proteómica , Azacitidina/farmacología , Cloruro de Sodio/farmacología , Tolerancia a la Sal/genética , Epigénesis Genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico
17.
Braz J Biol ; 82: e268350, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36350941

RESUMEN

Biochemical and physiological parameters, growth, and yield of field crops especially salt sensitive crops like chickpea are affected adversely by salinity in arid to semi-arid regions. To investigate the effect of different salinity levels on growth, biochemical and physiological parameters of chickpea genotypes, a pot experiment following CRD, two factor factorial design, was conducted in the glasshouse at the Institute of Biotechnology and Genetic Engineering, The University of Agriculture, Peshawar, Pakistan. Ten (10) kg of soil was filled in each pot and salinity levels were maintained @ S0= 0 mM NaCl, S1= 50 mM NaCl, S2= 100 mM NaCl and S3= 150 mM by applying NaCl and 5 genotypes of chickpea (KK-2, Bhakkar-2011, Bittle-98, Punjab-2008, and CM-98) were used. At crop maturity, growth parameters, physiological, biochemical, and ionic parameters were measured using standard analysis procedures. Salinity reduced the growth and yield of all genotypes, but the rate of decrease was different among the genotypes tested. From the results, a decrease in K concentration, K/Na ratio, transpiration rate, stomatal conductance, N, and P was observed in all genotypes with the increase in salinity. An increase in salinity level increased the proline content (35.45%), crude protein (42%), H2O2 (19%), lipid peroxidation (62%), carbohydrates (23.22%), and Na+ concentration (137%). The highest level of salinity, 150 mM NaCl has exhibited the highest salinity stress in all parameters. Genotype KK-2 and Bhakkar-11 showed a lower rate of relative decrease in yield (4.5 and 12%), K+/Na+ ratio (23.34 and 11.47%), and K+ concentration (7.9 and 11%), respectively, and the lowest relative increase in Na+ accumulation (20.3 and 0.48%), @ 50 mM salinity compared to control. Genotype KK-2 and Bhakkar-11 proved better @ 50mM salinity. The findings suggest that the critical level of the salinity must be kept in mind and the salt-tolerant genotypes should be cultivated in salt affected soils.


Asunto(s)
Cicer , Salinidad , Cicer/genética , Cicer/metabolismo , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/farmacología , Cloruro de Sodio/metabolismo , Cloruro de Sodio/farmacología , Sodio/metabolismo , Sodio/farmacología , Genotipo , Suelo
18.
Braz J Biol ; 84: e263214, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35857942

RESUMEN

The aim of the present work was to evaluate and analyze the growth and mineral nutrition response of stone pine (Pinus pinea L.) seedlings, an economically important forest species. We analyzed the salinity effects on the kinetics of growth, development, and absorption of nutrients of plants cultivated under controlled conditions on a solid organic substrate. Pinus pinea plants were able to tolerate 25 mM NaCl concentration without reduced growth compared to the non-saline control. However, the salt concentration of 50 mM significantly affected the seedling growth after two weeks of treatment. Root growth activity was decreased more than the aerial parts at applied NaCl concentrations. On the other hand, seedlings restricted the transport of Na+ ions to the aerial parts and were strongly selective in favour of K+ ions. The presence of NaCl in the culture medium decreased the absorption rate and the export of K+ and Na+ ions to the aerial parts. This was reflected in the accumulation way of these two ions in the whole plant.


Asunto(s)
Pinus , Nutrientes , Pinus/fisiología , Salinidad , Plantones , Cloruro de Sodio/farmacología
19.
Int J Mol Sci ; 23(14)2022 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-35886898

RESUMEN

The spontaneous interaction between human papillomavirus type 16 (HPV16) L1 virus-like particles (VLPs) and non-functionalized gold nanoparticles (nfGNPs) interferes with the nfGNPs' salt-induced aggregation, inhibiting the red-blue color shift in the presence of NaCl. Electron microscopy and competition studies showed that color-shift inhibition is a consequence of direct nfGNP-VLP interaction and, thus, may produce a negative impact on the virus entry cell process. Here, an in vitro infection system based on the HPV16 pseudovirus (PsV) was used to stimulate the natural infection process in vitro. PsVs carry a pseudogenome with a reporter gene, resulting in a fluorescent signal when PsVs infect a cell, allowing quantification of the viral infection process. Aggregation assays showed that nfGNP-treated PsVs also inhibit color shift in the presence of NaCl. High-resolution microscopy confirmed nfGNP-PsV complex formation. In addition, PsVs can interact with silver nanoparticles, suggesting a generalized interaction of metallic nanoparticles with HPV16 capsids. The treatment of PsVs with nfGNPs produced viral infection inhibition at a higher level than heparin, the canonical inhibitor of HPV infection. Thus, nfGNPs can efficiently interfere with the HPV16 cell entry process and may represent a potential active component in prophylactic formulations to reduce the risk of HPV infection.


Asunto(s)
Nanopartículas del Metal , Proteínas Oncogénicas Virales , Infecciones por Papillomavirus , Proteínas de la Cápside/genética , Oro/farmacología , Oro/uso terapéutico , Papillomavirus Humano 16/genética , Humanos , Nanopartículas del Metal/uso terapéutico , Nanopartículas del Metal/virología , Infecciones por Papillomavirus/prevención & control , Plata , Cloruro de Sodio/farmacología
20.
Braz J Biol ; 82: e260818, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35857948

RESUMEN

Cowpea (Vigna unguiculata (L.) Walp.) is a legume widely cultivated by small, medium and large producers in several Brazilian regions. However, one of the concerns for the production of cowpea in Brazil in recent years is the low rainfall activity in these regions, which generates the accumulation of salts on the surface. The objective of this work was to evaluate the effects of salt stress on growth parameters and enzyme activity in cowpea plants at different concentrations of brassinosteroids. Experiment was developed in a greenhouse using a completely randomized experimental design in a 3 x 3 factorial scheme. The treatments consisted of three levels of brassinosteroids (0, 3 and 6 µM EBL) and three levels of salt stress (0, 50 and 100 mM NaCl). Growth factors (height, diameter and number of leaves) decreased in the saline condition. With the presence of brassinosteroid the height did not increase, but the number of leaves did, mainly in the saline dosage of 100 mM NaCl. In the variable membrane integrity, brassinosteroid was efficient in both salinity dosages, the same not happening with the relative water content, where the saline condition did not affect the amount of water in the vegetable, with the application of brassino it remained high, decreasing only at dosage 100 mM NaCl. The nitrate reductase enzyme was greatly affected in the root system even with the application of increasing doses of brassino. Therefore, brassinosteroids as a promoter of saline tolerance in cowpea seedlings was positive. The concentration of 3µM of EBL provided the most satisfactory effect in tolerating the deleterious effects of the saline condition. The same cannot be concluded for the concentration of 6µM of EBL that did not promote tolerance to some variables.


Asunto(s)
Fabaceae , Vigna , Brasinoesteroides/metabolismo , Brasinoesteroides/farmacología , Estrés Salino , Cloruro de Sodio/metabolismo , Cloruro de Sodio/farmacología , Vigna/metabolismo , Agua/metabolismo
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