• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.244-244
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• 2017

Soil salinity due to accumulation of salts particularly sodium chloride affects agricultural lands and their vegetation. Generally, rice is a moderately sensitive plant with some cultivars with varying tolerance to salinity. Though there are physiological differences between salt-sensitive and salt-tolerant rice cultivars, both are still affected especially during high salinity and prolonged exposure. This also ultimately affects their indigenous bacterial endophytes particularly those that inhabit the rice seed endosphere. This study investigates the dynamic structure of seed bacterial endophytes of salt-sensitive and tolerant rice cultivars grown in different levels of soil salinity. Endophytic bacterial diversity was studied Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis. Results revealed a very interesting pattern of diversity and shifts in community structure of bacterial endophytes in the rice seeds. There is a general decrease in diversity for the salt-sensitive rice cultivar, IR29 as soil salinity increases. For the salt-tolerant cultivars, IC32 and IC37, diversity interestingly increased at moderate salinity then decreased at high soil salinity. The patterns of community structure is also strikingly different for the salt-sensitive and salt-tolerant rice cultivars. IR29 has a more even distribution of abundance, but under soil salinity, the community shifted where Curtobacterium, Pantoea, Flavobacterium and Microbacterium become the more dominant bacterial communities. For IC32 and IC37, the dominant bacterial groups under normal stress conditions were also the dominant bacterial groups during salt stress conditions. Their seed bacterial community is dominated by endophytes belonging to Microbacterium, Flavobacterium, Pantoea, Kosakonia and Enterobacter. Stenotrophomonas and Xanthomonas have not changed in terms of abundance under different salinity stress level in the salt-sensitive and salt-tolerant rice cultivars. This study showed that soil salinity greatly influenced the seed bacterial communities of rice seeds irrespective of their physiological tolerance to salinity.

• Journal of Nutrition and Health
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• v.50 no.3
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• pp.217-224
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• 2017

Purpose: Although it is well known thatmortality and morbidity due to cardiovascular diseases are higher in salt-sensitive subjects than in salt-resistant subjects, their underlying mechanisms related to obesity remain unclear. Here, we focused on salt-sensitive gene variants unrelated to monogenic obesity that interacted with sodium intake in humans. Methods: This review was written based on the modified $3^rd$ step of Khans' systematic review. Instead of the literature, subject genes were based on candidate genes screened from our preliminary Genome-Wide Association Study (GWAS). Finally, literature related to five genes strongly associated with salt sensitivity were analyzed to elucidate the mechanism of obesity. Results: Salt sensitivity is a measure of how blood pressure responds to salt intake, and people are either salt-sensitive or salt-resistant. Otherwise, dietary sodium restriction may not be beneficial for everyone since salt sensitivity may be associated with inherited susceptibility. According to our previous GWAS studies, 10 candidate genes and 11 single nucleotide polymorphisms (SNPs) associated with salt sensitivity were suggested, including angiotensin converting enzyme (ACE), ${\alpha}$-adducin1 (ADD1), angiotensinogen (AGT), cytochrome P450 family 11-subfamily ${\beta}$-2 ($CYP11{\beta}$-2), epithelial sodium channel (ENaC), G-protein b3 subunit (GNB3), G protein-coupled receptor kinases type 4 (GRK4 A142V, GRK4 A486V), $11{\beta}$-hydroxysteroid dehydrogenase type-2 (HSD $11{\beta}$-2), neural precursor cell-expressed developmentally down regulated 4 like (NEDD4L),and solute carrier family 12(sodium/chloride transporters)-member 3 (SLC 12A3). We found that polymorphisms of salt-sensitive genes such as ACE, $CYP11{\beta}$-2, GRK4, SLC12A3, and GNB3 may be positively associated with human obesity. Conclusion: Despite gender, ethnic, and age differences in genetics studies, hypertensive obese children and adults who are carriers of specific salt-sensitive genes are recommended to reduce their sodium intake. We believe that our findings can contribute to the prevention of early-onset of chronic diseases in obese children by facilitating personalized diet-management of obesity from childhood to adulthood.

• Journal of Plant Biotechnology
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• v.6 no.4
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• pp.205-212
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• 2004

The objectives were to compare the salt tolerance levels in the parental rice cultivar, Dongjinbyeo, and induced mutagenesis derived its lines for plant height, MDA, ATPase, POD, and 2-dimensional protein electrophoresis pattern in NaCl-containing hydroponic nutrient solutions. Rice plants isolated from a population of rice (Oryza sativa L. cv. Dongjinbyeo) mutation lines, which were generated in combination with in vitro selection and gamma-ray, exhibited salt tolerance. Line No. 18 had the longest plant, whereas NaCl-sensitive line (No. 25) had the shortest plant. The parent, and the sensitive line showed severe damage from salt stress. Tolerant lines (No. 18, 50) had a lower malonaldehyde (MDA) content than the sensitive one (Dongjinbyeo, No. 25) during salt stress. Several proteins showed significant quantitative variation through 2DE; phosphoribulokinase, peroxidase, oxygen evolving enhancer 1 and the $H^+-ATPase$, which are known to be involved in salt tolerance. The effect of salt on peroxidase and $H^+-ATPase$ activity in the seedlings of two groups with contrasting genotypes of rice was studied. A greater activity was recorded in the tolerant lines as compared to the sensitive ones (P<0.05, Duncan's test). The results indicate that salt tolerant lines expressed more salt stress-inducible proteins associated with salt tolerance than the sensitive lines during salt stress.

• Journal of Crop Science and Biotechnology
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• v.10 no.4
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• pp.257-264
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• 2007

Rice is one of the world's staple crops and is a major source of carbohydrate. Rice is exported from several countries, providing a major source of income. There are many documents reporting that rice is a salt-sensitive crop in its developmental stages. The objective of this investigation is to evaluate the effective salt-tolerance defense mechanisms in aromatic rice varieties. Pathumthani 1(PT1), Jasmine(KDML105), and Homjan(HJ) aromatic rice varieties were chosen as plant materials. Rice seedlings photoautotrophically grown in-vitro were treated with 0, 85, 171, 256, 342, and 427 mM NaCl in the media. Data, including sodium ion$(Na^+)$ and potassium ion$(K^+)$ accumulation, osmolarity, chlorophyll pigment concentration, and the fresh and dry weights of seedlings were collected after salt-treatment for 5 days. $Na^+$ in salt-stressed seedlings gradually accumulated, while $K^+$ decreased, especially in the 342-427 mM NaCl salt treatments. The $Na^+$ accumulation in both salt-stressed root and leaf tissues was positively related to osmolarity, leading to chlorophyll degradation. In the case of the different rice varieties, the results showed that the HJ variety was identified as being salt-tolerant, maintaining root and shoot osmolarities as well as pigment stabilization when exposed to salt stress or $Na^+$ enrichment in the cells. On the other hand, PT1 and KDML105 varieties were classified as salt-sensitive, determined by chlorophyll degradation using Hierarchical cluster analysis. In conclusion, the HJ-salt tolerant variety should be further utilized as a parental line or genetic resource in breeding programs because of the osmoregulation defensive response to salt-stress.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.452-461
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• 2023

Hypertension caused by high-fat and high-salt diets is is a well-known significant risk factor for cardiovascular and cerebrovascular diseases. In this study, to confirm the relationship between hypertension and immune cells, angiotensin (Ang) II was administered to Dahl salt-sensitive (SS) rats and Dahl salt-resistant (SR) rats. Then the expression of immune cells and the proinflammatory cytokines were compared between the SS and SR rats. It was observed that after administration of Ang II (50ng/kg/min) for three weeks, blood pressure was increased in the SS rats, but there was no significant change in the SR rats. In addition, the expression of T helper (Th) cells and Th 17 cells in the spleen and the expression of Th cell Rorγt and regulatory T regulatory (Treg) cells in the peripheral blood mononuclear cells did not show a significant difference between the two experimental groups even after the administration of Ang II.IL-1β expression was significantly increased in the kidney tissue of the SS rats, while there was no significant difference in the IL-6 expression in all the experimental groups. The results of this study suggest that Ang II induces hypertension by stimulating IL-1β secretion from renal macrophage in SS rats.

• International Journal of Oral Biology
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• v.47 no.4
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• pp.49-54
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• 2022

Taste is a basic sensation to get attracted toward nutritious foods or avoid possible harmful substances. The basic taste qualities in humans consist of sweet, bitter, umami, salty, and sour. Basically, sweet and umami tastes make food attractive, whereas bitter and sour tastes make it avoidable. Salty taste comprises basic salty and high salt taste. The basic salty taste is known as amiloride-sensitive salty taste, which is inhibited by amiloride, but the high salt taste is not sensitive to amiloride. Moreover, high salt taste can also cause avoidance behavior in human beings. Sodium, one of the most important cations in the body fluids of vertebrates, controls the volume of total body fluids and is a risk factor for cardiovascular diseases, such as hypertension. The concentration of sodium in body fluids must be under delicate control. A distinction between the salty taste and high salt taste would be a contributing mechanism to control the volume and/or osmolarity of body fluids.

• Journal of Nutrition and Health
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• v.35 no.7
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• pp.754-762
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• 2002

This study was performed to investigate the effect of sodium intake on blood pressure and blood parameters. 20 young adult women were fed the diets containing 290.5 mEq (high-Na diet) and 51.3 mEq (low-Na diet) Na for 6 days, respectively. BMI, DBP, and MBP were significantly lower in low-Na diet than those in high-Na diet. 20 subjects were divided into 3 groups according to the salt-sensitivity. In salt-sensitive group, decreases in SBP, DBP, and MBP by low-Na diet were shown. And there were not significant difference in blood pressure of salt-resistant group between high- and low-Na diet. In count-reactive group, MBP in low-Na diet was significantly higher than that in high-Na diet. Hemoglobin, creatinine, uric acid, and haptoglobin levels in serum were significantly higher in low-Na diet than those in high-Na diet. Among groups with different salt-sensitivity, increments of haptoglobin by low-Na diet were shown in salt-sensitive and counter-reactive groups. Actually, low sodium diet affects not only the blood pressure, but other biochemical parameters which in turn affect an individual overall health. Also salt-sensitivity should be considered as an important determinant. Therefore, for the patients who need restricted Na diet, it would be suggested that various biochemical changes and individual salt-sensitivity should be carefully considered along with dietary Na manipulation.

• Journal of Life Science
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• v.9 no.1
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• pp.22-25
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• 1999

In order to study the mechanism for the adaptation to salt stress, we mutagenized budding yeast Saccharomyces cerevisiae with Ethylmethane sulfonate, and isolated salt-tolerant mutants. Among the salt-tolerant mutants, two strains exhibit additional temperature sensitive phenotype. Here, we report that these two salt-tolerant mutants are specific to {TEX}$Na^{+}${/TEX} rather than general osmotic stress. These mutant strains may contain mutations in the genes involved in {TEX}$Na^{+}${/TEX} home-ostasis.

• Journal of Plant Biotechnology
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• v.38 no.1
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• pp.94-104
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• 2011

Salt stress is a major environmental factor influencing plant growth and development. To identify salt tolerance determinants, we systematically screened salt sensitive rice mutants by use of the Activator/Dissociation (Ac/Ds) transposon tagging system. In this study, we focused on the salt sensitive mutant line, designated SSM-1. A gene encoding a NAC transcription factor homologue was disrupted by the insertion of a Ds transposon into SSM-1 line. The OsNAC075 gene (EU541472) has 7 exons and encodes a protein (486-aa) containing the NAC domain in its N-terminal region. Sequence comparison showed that the OsNAC075 protein had a strikingly conserved region at the N-terminus, which is considered as the characteristic of the NAC protein family. OsNAC075 protein was orthologous to Arabidopsis thaliana ANAC075. Phylogenetic analysis confirmed OsNAC075 belonged to the OsNAC3 subfamily, which plays an important role in response to stress stimuli. RT-PCR analysis showed that the expression of OsNAC075 gene was rapidly and strongly induced by stresses such as NaCl, ABA and low temperature ($4^{\circ}C$). Our data suggest that OsNAC075 holds promising utility in improving salt tolerance in rice.

• Journal of Pharmaceutical Investigation
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• v.37 no.3
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• pp.173-177
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• 2007

The purpose of this study was to investigate the effect of salt formation on the percutaneous absorption of meloxicam through hairless mouse skin from a pressure sensitive adhesive (PSA) matrix. In addition, the influences of enhancers on the permeation of meloxicam or meloxicam-ethanolamine (MX-EA) salts across the hairless mouse skin were evaluated using a flow-through diffusion cell system. The salt formation of meloxicam resulted in lower permeation rate than the parent drug. $Span^{(R)}$ 80 provided the highest enhancing effect for meloxicam and meloxicam monoethanolamine salt. The maximum amount of the drug that can be loaded without retarding permeation rate was different depending on the compound. No relationship was found between the fluxes of meloxicam or MX-EA salts from saturated solutions and those from PSA matrices containing the same enhancer.