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12 pages, 1511 KiB  
Article
Biological Activities of Glucosinolate and Its Enzymatic Product in Moringa oleifera (Lam.)
by Jinglin Wang, Saifei Yang, Sijia Shen, Chunxian Ma and Rui Chen
Int. J. Mol. Sci. 2025, 26(15), 7323; https://doi.org/10.3390/ijms26157323 (registering DOI) - 29 Jul 2025
Viewed by 164
Abstract
In this study, using 70% anhydrous ethanol as the extraction solvent, Moringa oleifera Lam. seed powder was extracted with the microwave-assisted extraction method, followed by purification using macroporous adsorbent resin NKA-9. The purified glucosinolate was subsequently hydrolyzed with myrosinase. The glucosinolate and its [...] Read more.
In this study, using 70% anhydrous ethanol as the extraction solvent, Moringa oleifera Lam. seed powder was extracted with the microwave-assisted extraction method, followed by purification using macroporous adsorbent resin NKA-9. The purified glucosinolate was subsequently hydrolyzed with myrosinase. The glucosinolate and its enzymatic product were identified as 4-(α-L-rhamnopyranosyloxy) benzyl glucosinolate (4-RBMG) and benzyl isothiocyanate (BITC) by UV–Vis, FT-IR, NMR, and MS. The bioactivities, including anti-oxidation, anti-inflammation, and anti-tumor activities of 4-RBMG and BITC, were systematically evaluated and compared. The results show that at 5–20 mg/mL, the anti-oxidation effects of 4-RBMG on DPPH and ABTS free radicals are superior to those of BITC. However, at the same concentrations, BITC has stronger anti-inflammatory and anti-tumor activities compared to 4-RBMG. Notably, at a concentration of 6.25 μmol/L, BITC significantly inhibited NO production with an inhibitory rate of 96.67% without cytotoxicity. Additionally, at a concentration of 40 μmol/L, BITC exhibited excellent inhibitory effects on five tumor cell lines, with the cell inhibitory rates of leukemia HL-60, lung cancer A549, and hepatocellular carcinoma HepG2 exceeding 90%. This study provides some evidence that the enzymatic product, BITC, shows promise as a therapeutic agent for tumor suppression and inflammation reduction. Full article
(This article belongs to the Section Bioactives and Nutraceuticals)
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43 pages, 3064 KiB  
Review
Cardiac Glycosides: From Natural Defense Molecules to Emerging Therapeutic Agents
by Arturo Ponce, Catalina Flores-Maldonado and Ruben G. Contreras
Biomolecules 2025, 15(6), 885; https://doi.org/10.3390/biom15060885 - 17 Jun 2025
Viewed by 1357
Abstract
Cardiac glycosides (CGs), a class of plant- and animal-derived compounds historically used to treat heart failure, have garnered renewed interest for their diverse pharmacological properties beyond Na+/K+-ATPase (NKA) inhibition. Recent studies reveal that CGs modulate key signaling pathways—such as [...] Read more.
Cardiac glycosides (CGs), a class of plant- and animal-derived compounds historically used to treat heart failure, have garnered renewed interest for their diverse pharmacological properties beyond Na+/K+-ATPase (NKA) inhibition. Recent studies reveal that CGs modulate key signaling pathways—such as NF-κB, PI3K/Akt, JAK/STAT, and MAPK—affecting processes central to cancer, viral infections, immune regulation, and neurodegeneration. In cancer, CGs induce multiple forms of regulated cell death, including apoptosis, ferroptosis, pyroptosis, and immunogenic cell death, while also inhibiting angiogenesis, epithelial–mesenchymal transition, and cell cycle progression. They demonstrate broad-spectrum antiviral activity by disrupting viral entry, replication, and mRNA processing in viruses such as HSV, HIV, influenza, and SARS-CoV-2. Immunologically, CGs regulate Th17 differentiation via RORγ signaling, although both inhibitory and agonistic effects have been reported. In the nervous system, CGs modulate neuroinflammation, support synaptic plasticity, and improve cognitive function in models of Alzheimer’s disease, epilepsy, and multiple sclerosis. Despite their therapeutic potential, clinical translation is hindered by narrow therapeutic indices and systemic toxicity. Advances in drug design and nanocarrier-based delivery are critical to unlocking CGs’ full potential as multi-target agents for complex diseases. This review synthesizes the current knowledge on the emerging roles of CGs and highlights strategies for their safe and effective repurposing. Full article
(This article belongs to the Section Natural and Bio-derived Molecules)
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34 pages, 2415 KiB  
Article
Strategies to Develop Na,K-ATPase-α4 Inhibitors as Male Contraceptives
by Shameem S. Syeda, Gladis Sánchez, Jeffrey P. McDermott, Narsihmulu Cheryala, Henry L. Wong, Gunda I. Georg and Gustavo Blanco
Int. J. Mol. Sci. 2025, 26(12), 5646; https://doi.org/10.3390/ijms26125646 - 12 Jun 2025
Viewed by 858
Abstract
Male contraception remains an unmet need. Na,K-ATPase α4 (NKA α4), a specific Na⁺/K⁺ transporter of the sperm flagellum, is an attractive target for male contraception. NKA α4 is critical for sperm motility and fertility, and its deletion in male mice causes complete infertility. [...] Read more.
Male contraception remains an unmet need. Na,K-ATPase α4 (NKA α4), a specific Na⁺/K⁺ transporter of the sperm flagellum, is an attractive target for male contraception. NKA α4 is critical for sperm motility and fertility, and its deletion in male mice causes complete infertility. Our previous structure–activity relationship (SAR) studies on a cardenolide scaffold identified a highly selective, safe NKAα4 inhibitor, but its complex, heavily hydroxylated structure posed challenges for modification and optimization. To address this, we employed a structural simplification strategy to synthesize novel steroidal and non-steroidal analogs and examined their effects on NKAα4 inhibition and sperm motility. Both series reduced sperm motility (up to ~50%), with IC50 values in the picomolar range. Compounds 13 and 45 displayed specificities for NKAα4 over NKAα1, did not affect sperm viability, and showed no reversibility in vitro. Notably, 45, featuring a hexahydronaphthalene core and a benzyltriazole moiety at C5, exhibited potent, highly selective NKAα4 inhibition, reduced sperm motility in vitro and in vivo, and blocked fertilization in vitro. This highlights 45 as a promising lead for non-hormonal male contraception and indicates that the newly generated series of compounds possess the key characteristics needed for further development as potential non-hormonal male contraceptive agents. Full article
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15 pages, 6714 KiB  
Article
Osmoregulation and Physiological Response of Largemouth Bass (Micropterus salmoides) Juvenile to Different Salinity Stresses
by Yang Liu, Jing Tian, Hongmei Song, Tao Zhu, Caixia Lei, Jinxing Du and Shengjie Li
Int. J. Mol. Sci. 2025, 26(8), 3847; https://doi.org/10.3390/ijms26083847 - 18 Apr 2025
Viewed by 514
Abstract
The distribution of saline-alkali water is extensive and is increasing globally each year. Fully utilizing saline-alkali water for aquaculture can help alleviate the scarcity of freshwater resources in global fisheries. As a major economic fish species, the largemouth bass (Micropterus salmoides) [...] Read more.
The distribution of saline-alkali water is extensive and is increasing globally each year. Fully utilizing saline-alkali water for aquaculture can help alleviate the scarcity of freshwater resources in global fisheries. As a major economic fish species, the largemouth bass (Micropterus salmoides) holds significant potential for aquaculture in saline-alkali water. In the present study, we evaluated its tolerance to different salinities (0 ppt, 6 ppt, 9 ppt, 12 ppt, 15 ppt, and 18 ppt) and investigated tissue pathology, serum biochemical indicators, enzyme activities of osmolality and antioxidant, and the relative expression of Na-K-2Cl 1a cotransporter (NKCC1a) under different saline stress (0 ppt, 6 ppt, 9 ppt, and 12 ppt). The largemouth bass 96 h mortality rate increased with increasing salinity, and the LC50 for 96 h was 14.28 ppt based on the mortality results. High salinity group (12 ppt) caused gill and intestinal damage, including necrosis and cell shedding, while 6 ppt had no adverse effects, and the 9 ppt between the two salinities showed an adaptive change histologically. Serum osmolality, Na+, Cl, and cortisol levels of the high salinity group were significantly higher than of the low salinities (p < 0.05). Similarly, Na+/K+-ATPase (NKA), Ca2+-Mg2+-ATPase (CMA), and superoxide dismutase (SOD) activities of 12 ppt peaked at 24 h (15.7 U/mgprot, 11.5 U/mgprot, and 243 U/mgprot), which is significantly different compared to the other three groups (p < 0.05). The expression of NKCC1a was significantly upregulated at 9 ppt and 12 ppt, suggesting its role in osmoregulation. Furthermore, the expression of NKCC1a in the gill is 2–4 times higher than that in the intestine. These results suggested that largemouth bass can be cultured at 6 ppt and selectively bred for tolerance at 9 ppt. NKA activity, cortisol levels, and NKCC1a expression can be used as a marker of salinity suitability. These findings provide insight into the adaptive mechanisms underlying the physiological responses to acute salinity stress and will contribute to improving aquaculture in saline waters. Full article
(This article belongs to the Section Molecular Biology)
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26 pages, 4940 KiB  
Article
Integration of Gill and Intestinal Osmoregulatory Functions to Assess the Smoltification Window in Atlantic Salmon
by Jonás I. Silva-Marrero, Floriana Lai, Sigurd O. Handeland, Cindy Pedrosa, Virginie Gelebart, Pablo Balseiro, Juan Fuentes, Ivar Rønnestad and Ana S. Gomes
Fishes 2025, 10(3), 119; https://doi.org/10.3390/fishes10030119 - 8 Mar 2025
Cited by 2 | Viewed by 1466
Abstract
The transfer time of Atlantic salmon smolts from freshwater to seawater remains a challenge in aquaculture, with the “smolt window” referring to the optimal timeframe for seawater readiness. Our study monitored Atlantic salmon osmoregulatory adaptations during smoltification under continuous light (LL) and winter [...] Read more.
The transfer time of Atlantic salmon smolts from freshwater to seawater remains a challenge in aquaculture, with the “smolt window” referring to the optimal timeframe for seawater readiness. Our study monitored Atlantic salmon osmoregulatory adaptations during smoltification under continuous light (LL) and winter signal regime (6 weeks LD 12:12) followed by 6 or 8 weeks of constant light. Fish were subsequently reared in seawater for 8 weeks and subjected to a stress event of cyclic hypoxia at the conclusion of the trial. Significant differences in growth trajectories were observed between the LL and LD groups, with fish receiving the winter signal showing compensatory growth after seawater transfer. Gill Na+/K+-ATPase (NKA) activity, plasma ions, glucose, and cortisol levels confirmed the importance of the winter signal for seawater adaptation. Molecular markers, including nka isoforms, Na+-K+-2Cl cotransporter (nkcc), cystic fibrosis transmembrane conductance regulator (cftr), and Na+/HCO3 cotransporter (nbc), showed distinct temporal expression patterns, particularly in gills and midgut. Notably, the LD group with delayed seawater transfer exhibited enhanced growth and improved hypo-osmoregulatory capacity. These findings underscore the advantages of a winter signal in smoltification and suggest that delaying seawater transfer for up to 8 weeks could be beneficial. Full article
(This article belongs to the Special Issue Rhythms in Marine Fish and Invertebrates)
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16 pages, 2260 KiB  
Article
Purification and Identification of Flavonoids from Prunus mume and Its Anti-Photoaging Activities on UVB-Induced Human Keratinocytes
by Yuxuan Liu, Mengdie He, Xinxin Wei, Qifeng Han, Xiang Yang, Gangyi Huang, Chen Zhang, Mengqi Wu and Wenqing Zhang
Cosmetics 2025, 12(1), 19; https://doi.org/10.3390/cosmetics12010019 - 23 Jan 2025
Viewed by 1463
Abstract
Prunus mume (Armeniaca mume Sieb. var. mume f. viridicalyx (Makino) T. Y. Chen) is a common landscape plant. It has rich flavonoid content, which shows strong biological activities. In this study, the application potential of flavonoids in Prunus mume in anti-photoaging cosmetics [...] Read more.
Prunus mume (Armeniaca mume Sieb. var. mume f. viridicalyx (Makino) T. Y. Chen) is a common landscape plant. It has rich flavonoid content, which shows strong biological activities. In this study, the application potential of flavonoids in Prunus mume in anti-photoaging cosmetics was developed. Firstly, the flavonoids in Prunus mume were extracted by the heating reflux method, and the total flavonoid content reached 192 mg/g under the optimal process conditions determined by orthogonal testing. Then, the crude extract (PMCE) was purified by NKA-II resin column chromatography, and the purity of the flavonoids reached 83.99%. Subsequently, the Prunus mume purified product (PMPP) was analyzed by UHPLC-DAD-QTOF-MS/MS and 45 compounds were identified including flavonoid glycosides, phenolic acids and p-coumaroyl acetylated sucrose. In addition, in vitro biological experiments showed that PMPP had significant repair effects on UVB-induced photoaging of human keratinocytes (HaCaT), lowering reactive oxygen species (ROS) and malondialdehyde (MDA) levels, restoring superoxide dismutase (SOD) activity, and promoting hyaluronic acid (HA) secretion and Aquaporins-3 (AQP-3) levels. The results laid the foundation for the development of the flavonoids in Prunus mume as materials for anti-photoaging cosmetics. Full article
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14 pages, 286 KiB  
Article
Rice-Fish Farming Improved Antioxidant Defences, Glucose Metabolism, and Muscle Nutrient of Carassius auratus in Sichuan Province
by Tao Yan, Yun-Yi Xie, Bo Zhou, Xu Kuang, Qing-Zhi Li, Feng-Qi Zhao, Qian-Dong Li and Bin He
Metabolites 2024, 14(12), 710; https://doi.org/10.3390/metabo14120710 - 17 Dec 2024
Cited by 1 | Viewed by 1158
Abstract
Rice-fish farming is an ancient and enduring aquaculture model in China. This study aimed to assess the variations in digestive enzymes, antioxidant properties, glucose metabolism, and nutritional content between Carassius auratus reared in paddy fields and ponds. Notably, the levels of amylase and [...] Read more.
Rice-fish farming is an ancient and enduring aquaculture model in China. This study aimed to assess the variations in digestive enzymes, antioxidant properties, glucose metabolism, and nutritional content between Carassius auratus reared in paddy fields and ponds. Notably, the levels of amylase and trypsin in C. auratus from rice paddies were considerably higher compared to those from ponds. Additionally, the hepatic catalase (CAT) activity in fish from paddy (2.45 ± 0.16 U/mg) exceeded that of their pond counterparts (2.27 ± 0.25 U/mg). Regarding glucose metabolism, the activities of key enzymes such as Na+/K+-ATPase (NKA) (paddy: 82.45 ± 6.11 U/g; pond: 78.53 ± 7.18 U/g), hexokinase (HK) (paddy: 9.55 ± 0.58 U/g; pond: 8.83 ± 0.72 U/g), glucokinase (GK) (paddy: 4.09 ± 0.21 IU/g; pond: 3.44 ± 0.33 IU/g), glucose-6-phosphatase (G6Pase) (paddy: 85.71 ± 4.49 IU/g; pond: 79.12 ± 9.34 IU/g), and glucose-6-phosphate dehydrogenase (G6PDH) (paddy: 47.23 ± 3.22 U/g; pond: 42.31 ± 4.93 U/g) were significantly elevated in rice paddy-cultured fish compared to those in ponds. Conversely, phosphor-pyruvate kinase (PK) (paddy: 418.15 ± 31.89 U/g; pond: 570.16 ± 56.06 U/g) activity was markedly reduced in the paddy group. Hepatic glycogen content (paddy: 15.70 ± 0.98 ng/g; pond: 14.91 ± 1.24 ng/g) was also substantially higher in fish from paddy, although no significant differences in muscle glycogen content (paddy: 7.14 ± 0.59 ng/g; pond: 6.70 ± 0.52 ng/g) were observed between the two environments. In terms of nutritional composition, fish raised in paddy exhibited higher crude protein (paddy: 18.46 ± 0.47 g/100 g muscle; pond: 15.57 ± 0.25 g/100 g muscle) and crude ash (paddy: 1.19 ± 0.02 g/100 g muscle; pond: 0.97 ± 0.02 g/100 g muscle) than those in ponds, whereas the crude fat (paddy: 0.87 ± 0.04 g/100 g muscle; pond: 1.66 ± 0.04 g/100 g muscle) was notably lower in paddy fish. Furthermore, fish from rice paddies had a greater total content of monounsaturated fatty acids (MUFA) (paddy: 4.25 ± 0.24 g/100 g muscle; pond: 6.73 ± 0.27 g/100 g muscle), non-essential amino acids (NEAA) (paddy: 9.04 ± 0.3 g/100 g muscle; pond: 7.19 ± 0.21 g/100 g muscle), and delicious amino acids (DAA) (paddy: 7.11 ± 0.2 g/100 g muscle; pond: 5.45 ± 0.19 g/100 g muscle) compared to those from pond cultures. These findings suggest that rice-fish co-culture systems can yield healthier and more environmentally sustainable aquatic products by improving feed digestion and optimizing nutrient metabolism. Full article
(This article belongs to the Special Issue Metabolism and Nutrition in Fish)
13 pages, 1884 KiB  
Article
Changes in Physiological Homeostasis in the Gills of Litopenaeus vannamei Under Carbonate Alkalinity Stress and Recovery Conditions
by Meng Xiao, Yuxiu Nan, Yukai Yang, Hua Li and Yafei Duan
Fishes 2024, 9(11), 463; https://doi.org/10.3390/fishes9110463 - 15 Nov 2024
Cited by 4 | Viewed by 1102
Abstract
Carbonate alkalinity (CA) is the major toxic factor that interferes with the survival and growth of shrimp in saline–alkaline water. Gills are the main entry organ for CA toxicity in shrimp. In this study, low-salinity cultured Litopenaeus vannamei were exposed to 5 mmol/L [...] Read more.
Carbonate alkalinity (CA) is the major toxic factor that interferes with the survival and growth of shrimp in saline–alkaline water. Gills are the main entry organ for CA toxicity in shrimp. In this study, low-salinity cultured Litopenaeus vannamei were exposed to 5 mmol/L CA stress for 7 days and then recovered for 7 days to explore the physiological changes in the gills under CA stress and recovery conditions at multiple biological levels. The results showed that CA stress increased the activities of antioxidative biochemical indexes (T-AOC, T-SOD, and POD) and the relative expression levels of romo1, nrf2, and gpx genes, while it decreased the relative expression levels of the sod and hsp70 genes. In addition, CA stress also increased the relative expression levels of genes involved in endoplasmic reticulum (ER) stress (bip, ire1, and xbp1), immunity (alf, crus, pen-3 and propo), apoptosis (casp-3), detoxification metabolism (cyp450 and gst), and osmotic adjustment (ca, nka-α, nka-β, vatp, nhe, clc, aqp, tip4, and ccp). Although changes in some of the physiological indexes were reversed after the CA stress was relieved, they still could not effectively recover to the control level. These results reveal that CA stress has a negative impact on physiological homeostasis in the shrimp gills by inducing oxidation and ER stress and by interfering with immunity, apoptosis, detoxification, and osmotic adjustment. Full article
(This article belongs to the Special Issue Physiological Response Mechanisms of Aquatic Animals to Stress)
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14 pages, 2341 KiB  
Article
Tissue-Specific Toxicity in Common Carp (Cyprinus carpio) Caused by Combined Exposure to Triphenyltin and Norfloxacin
by Yiwei Liu, Luoxin Li, Siqi Zhang, Minghao Yin, Tengzhou Li, Bianhao Zeng, Ling Liu, Ping Li and Zhihua Li
Fishes 2024, 9(10), 415; https://doi.org/10.3390/fishes9100415 - 17 Oct 2024
Viewed by 1091
Abstract
Triphenyltin (TPT) is a commonly encountered organotin compound known for its endocrine-disrupting properties; it frequently interacts with antibiotics in aquatic environments. In this study, common carp (Cyprinus carpio) (17.43 ± 4.34 g, 11.84 ± 0.88 cm) were chosen as the experimental organisms. According [...] Read more.
Triphenyltin (TPT) is a commonly encountered organotin compound known for its endocrine-disrupting properties; it frequently interacts with antibiotics in aquatic environments. In this study, common carp (Cyprinus carpio) (17.43 ± 4.34 g, 11.84 ± 0.88 cm) were chosen as the experimental organisms. According to the environmental concentration in the heavily polluted area, the control group and the experimental groups were exposed for 21 days to the following treatments: 1 μg/L TPT, 1 mg/L NOR, and a combination of 1 μg/L TPT plus 1 mg/L NOR. The investigation examined the individual and combined toxicities of TPT and norfloxacin (NOR) on the gill, liver, and gut tissues of common carp in highly polluted areas. The findings revealed tissue-specific variations in 1L-1β enzyme activity; specifically, 1L-1β enzyme activity exhibited a significant reduction in liver tissue under both NOR exposure and combined exposure, indicating that high concentrations of NOR had the most pronounced impact on the immune system of liver tissue. Furthermore, the gene expression levels of IL-1β, Lysozyme-C, NKA, and CPT1 in the liver, intestinal, and gill tissues showed differences after exposure. In addition, TPT exerted the most significant effect on intestinal tissue, followed by the liver and gill tissues. Interestingly, when TPT and NOR were exposed together, the toxic effects on all tissues were reduced, suggesting the existence of antagonistic effects. Full article
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29 pages, 2013 KiB  
Review
Na+/K+-ATPase: More than an Electrogenic Pump
by Ruben G. Contreras, Antonio Torres-Carrillo, Catalina Flores-Maldonado, Liora Shoshani and Arturo Ponce
Int. J. Mol. Sci. 2024, 25(11), 6122; https://doi.org/10.3390/ijms25116122 - 1 Jun 2024
Cited by 21 | Viewed by 8950
Abstract
The sodium pump, or Na+/K+-ATPase (NKA), is an essential enzyme found in the plasma membrane of all animal cells. Its primary role is to transport sodium (Na+) and potassium (K+) ions across the cell membrane, [...] Read more.
The sodium pump, or Na+/K+-ATPase (NKA), is an essential enzyme found in the plasma membrane of all animal cells. Its primary role is to transport sodium (Na+) and potassium (K+) ions across the cell membrane, using energy from ATP hydrolysis. This transport creates and maintains an electrochemical gradient, which is crucial for various cellular processes, including cell volume regulation, electrical excitability, and secondary active transport. Although the role of NKA as a pump was discovered and demonstrated several decades ago, it remains the subject of intense research. Current studies aim to delve deeper into several aspects of this molecular entity, such as describing its structure and mode of operation in atomic detail, understanding its molecular and functional diversity, and examining the consequences of its malfunction due to structural alterations. Additionally, researchers are investigating the effects of various substances that amplify or decrease its pumping activity. Beyond its role as a pump, growing evidence indicates that in various cell types, NKA also functions as a receptor for cardiac glycosides like ouabain. This receptor activity triggers the activation of various signaling pathways, producing significant morphological and physiological effects. In this report, we present the results of a comprehensive review of the most outstanding studies of the past five years. We highlight the progress made regarding this new concept of NKA and the various cardiac glycosides that influence it. Furthermore, we emphasize NKA’s role in epithelial physiology, particularly its function as a receptor for cardiac glycosides that trigger intracellular signals regulating cell–cell contacts, proliferation, differentiation, and adhesion. We also analyze the role of NKA β-subunits as cell adhesion molecules in glia and epithelial cells. Full article
(This article belongs to the Special Issue Ion Pumps: Molecular Mechanisms, Structure, Physiology)
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14 pages, 6494 KiB  
Article
Toxicity of Ammonia Stress on the Physiological Homeostasis in the Gills of Litopenaeus vannamei under Seawater and Low-Salinity Conditions
by Yuxiu Nan, Meng Xiao, Yafei Duan and Yukai Yang
Biology 2024, 13(4), 281; https://doi.org/10.3390/biology13040281 - 21 Apr 2024
Cited by 9 | Viewed by 2630
Abstract
Ammonia is a major water quality factor influencing the survival and health of shrimp, among which the gill is the main effector organ for ammonia toxicity. In this study, we chose two types of Litopenaeus vannamei that were cultured in 30‰ seawater and [...] Read more.
Ammonia is a major water quality factor influencing the survival and health of shrimp, among which the gill is the main effector organ for ammonia toxicity. In this study, we chose two types of Litopenaeus vannamei that were cultured in 30‰ seawater and domesticated in 3‰ low salinity, respectively, and then separately subjected to ammonia stress for 14 days under seawater and low-salinity conditions, of which the 3‰ low salinity-cultured shrimp were domesticated from the shrimp cultured in 30‰ seawater after 27 days of gradual salinity desalination. In detail, this study included four groups, namely the SC group (ammonia-N 0 mg/L, salinity 30‰), SAN group (ammonia-N 10 mg/L, salinity 30‰), LC group (ammonia-N 0 mg/L, salinity 3‰), and LAN group (ammonia-N 10 mg/L, salinity 3‰). The ammonia stress lasted for 14 days, and then the changes in the morphological structure and physiological function of the gills were explored. The results show that ammonia stress caused the severe contraction of gill filaments and the deformation or even rupture of gill vessels. Biochemical indicators of oxidative stress, including LPO and MDA contents, as well as T-AOC and GST activities, were increased in the SAN and LAN groups, while the activities of CAT and POD and the mRNA expression levels of antioxidant-related genes (nrf2, cat, gpx, hsp70, and trx) were decreased. In addition, the mRNA expression levels of the genes involved in ER stress (ire1 and xbp1), apoptosis (casp-3, casp-9, and jnk), detoxification (gst, ugt, and sult), glucose metabolism (pdh, hk, pk, and ldh), and the tricarboxylic acid cycle (mdh, cs, idh, and odh) were decreased in the SAN and LAN groups; the levels of electron-transport chain-related genes (ndh, cco, and coi), and the bip and sdh genes were decreased in the SAN group but increased in the LAN group; and the level of the ATPase gene was decreased but the cytc gene was increased in the SAN and LAN groups. The mRNA expression levels of osmotic regulation-related genes (nka-β, ca, aqp and clc) were decreased in the SAN group, while the level of the ca gene was increased in the LAN group; the nka-α gene was decreased in both two groups. The results demonstrate that ammonia stress could influence the physiological homeostasis of the shrimp gills, possibly by damaging the tissue morphology, and affecting the redox, ER function, apoptosis, detoxification, energy metabolism, and osmoregulation. Full article
(This article belongs to the Special Issue Metabolic and Stress Responses in Aquatic Animals)
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15 pages, 1630 KiB  
Article
Effects of Dietary Inosine 5′-Monophosphate Supplementation on the Growth Performance and Salinity and Oxidative Stress Resistance of Gibel Carp (Carassius auratus gibelio)
by Luohai Hua, Peiyu Zhang, Haokun Liu, Mingze Xin, Zhiwei Zhang, Dong Han, Zhimin Zhang, Xiaoming Zhu, Junyan Jin, Yunxia Yang and Shouqi Xie
Antioxidants 2024, 13(4), 487; https://doi.org/10.3390/antiox13040487 - 19 Apr 2024
Viewed by 1755
Abstract
An 88-day feeding trial was conducted to evaluate the effects of dietary inosine 5′-monophosphate (5′-IMP) on the growth performance and salinity and oxidative stress resistance in the juvenile gibel carp CAS III (Carassius auratus gibelio; initial body weight: 7.48 g). Four [...] Read more.
An 88-day feeding trial was conducted to evaluate the effects of dietary inosine 5′-monophosphate (5′-IMP) on the growth performance and salinity and oxidative stress resistance in the juvenile gibel carp CAS III (Carassius auratus gibelio; initial body weight: 7.48 g). Four isonitrogenous and isoenergetic diets containing exogenous 5′-IMP were formulated. P1, P2, P3 and P4 were diets containing 5′-IMP at four concentrations (0, 1, 2 and 4 g kg−1). The four diets were randomly allotted to triplicate tanks in a recirculating system. After the feeding trial, six fish per tank were netted randomly and placed into 12‰ saline water to test their response to salinity stress. The results indicated that the feed conversion rate was enhanced by dietary supplementation with 5′-IMP. The appetite, plasma neuropeptide Y level and feeding rate of the P3 group were lower than those in the control treatment group. Dietary supplementation with 5′-IMP improved the osmoregulatory adaptation of gibel carp under acute salinity stress. Six hours after the salinity stress treatment, in the dietary 5′-IMP treatment group, the plasma cortisol and K+ concentrations were lower and the Na+/K+-ATPase activity was greater than that in the control group. Dietary supplementation with 5′-IMP promoted the expression of the glucocorticoid receptors NKA-α1b and NKCC and retarded the expression of Hsp70 in P4-treated gill filaments and kidneys. Dietary supplementation with 5′-IMP resulted in a stable oxidative-stress-resistant phenotype characterized by increased levels of cellular antioxidants, including SOD, catalase, glutathione peroxidase, glutathione reductase and MPO. The above results of the current study demonstrate that supplementation of 5′-IMP can promote feed utilization and have positive influences on the salinity and oxidative stress resistance of gibel carp. Full article
(This article belongs to the Special Issue Oxidative Stress and Nutrition in Aquatic Animals)
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21 pages, 5518 KiB  
Article
Effects of Electroporation on the Function of Sarco/Endoplasmic Reticulum Ca2+-ATPase and Na+,K+-ATPase in H9c2 Cells
by Vid Jan, Maida Jusović and Damijan Miklavčič
Appl. Sci. 2024, 14(7), 2695; https://doi.org/10.3390/app14072695 - 22 Mar 2024
Cited by 1 | Viewed by 1895
Abstract
Pulsed field ablation (PFA) is a promising new treatment for atrial fibrillation (AF), in which pulmonary vein isolation is achieved by irreversible electroporation. Electroporation causes ATP to leak through the permeabilized membrane. ATP is required both for the healing of the cell membrane [...] Read more.
Pulsed field ablation (PFA) is a promising new treatment for atrial fibrillation (AF), in which pulmonary vein isolation is achieved by irreversible electroporation. Electroporation causes ATP to leak through the permeabilized membrane. ATP is required both for the healing of the cell membrane and for the functioning of ion pumps, such as sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) or Na+,K+-ATPase (NKA), which play a key role in maintaining continuous contractions of the heart muscle. We investigated the effects of electroporation on the expression of ion pumps and possible correlations with the activation of AMPK, the main energy sensor in cells. H9c2 rat cardiac cells were exposed to either monopolar or bipolar (H-FIRE) pulses. Cells lysed 4 or 24 h after electroporation were used for mRNA and protein expression analyses. Overall, both pulse protocols caused a dose-dependent downregulation of crucial SERCA and NKA isoforms, except for NKAα2 and β3, which were upregulated after 24 h. Monopolar pulses also decreased the phosphorylation of FXYD1, which may cause an inhibition of NKA activity. Both pulse protocols caused an increased AMPK activity, which may decrease both SERCA and NKA activity via calcium/calmodulin-dependent protein kinase. Our results provide important new insights into what happens in surviving cardiomyocytes after they are exposed to PFA. Full article
(This article belongs to the Special Issue Advances in Electroporation Systems and Applications)
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11 pages, 1616 KiB  
Article
The Influence of Triphenyltin Exposure on the Osmoregulatory Capacity of Marine Medaka (Oryzias melastigma) at Different Salinities
by Teng-Zhou Li, Cheng-Zhuang Chen, Shao-Ying Xing, Ling Liu, Ping Li and Zhi-Hua Li
Water 2024, 16(7), 921; https://doi.org/10.3390/w16070921 - 22 Mar 2024
Cited by 2 | Viewed by 1494
Abstract
Triphenyltin (TPT) is an organotin pollutant widely found in the aquatic environment. It has endocrine-disrupting and osmotic pressure toxicity. In this study, the physiological and biochemical effects of TPT and various salinities were investigated in different tissues (gut, gill, and brain) of marine [...] Read more.
Triphenyltin (TPT) is an organotin pollutant widely found in the aquatic environment. It has endocrine-disrupting and osmotic pressure toxicity. In this study, the physiological and biochemical effects of TPT and various salinities were investigated in different tissues (gut, gill, and brain) of marine medaka. The exposure experiments were conducted for 42 days in different salinities (0, 15, and 30 ppt) without TPT exposure and in different salinity groups with TPT exposure concentrations of 100 ng/L, respectively. The results showed that the Na+-K+-ATPase (NKA) and Ca2+ATPase activity had significant tissue-specific differences, with the highest activity observed in the gills, indicating their major contribution to osmoregulation. Changes in salinity also resulted in significant alterations in the ion concentrations of the gut and gill tissues in the 0-C and 15-C groups. While the changes in Na+ and Cl were relatively stable, the presence of TPT disrupted the regulation of Ca2+ and K+. In conclusion, substantial variations were observed in the osmoregulatory capacity of marine medaka tissues. Environmental concentrations of TPT had little effect on osmotic enzyme activity but interfered with the regulation of Ca2+ and K+ concentrations in the tissues. This study provides valuable insights into the osmotic toxicity of TPT in aquatic environments with different salinities. Full article
(This article belongs to the Section Water Quality and Contamination)
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16 pages, 3187 KiB  
Article
Simultaneous Increases in Intracellular Sodium and Tonicity Boost Antimicrobial Activity of Macrophages
by Luka Krampert, Thomas Ossner, Agnes Schröder, Valentin Schatz and Jonathan Jantsch
Cells 2023, 12(24), 2816; https://doi.org/10.3390/cells12242816 - 11 Dec 2023
Cited by 4 | Viewed by 2297
Abstract
Inflamed and infected tissues can display increased local sodium (Na+) levels, which can have various effects on immune cells. In macrophages, high salt (HS) leads to a Na+/Ca2+-exchanger 1 (NCX1)-dependent increase in intracellular Na+ levels. This [...] Read more.
Inflamed and infected tissues can display increased local sodium (Na+) levels, which can have various effects on immune cells. In macrophages, high salt (HS) leads to a Na+/Ca2+-exchanger 1 (NCX1)-dependent increase in intracellular Na+ levels. This results in augmented osmoprotective signaling and enhanced proinflammatory activation, such as enhanced expression of type 2 nitric oxide synthase and antimicrobial function. In this study, the role of elevated intracellular Na+ levels in macrophages was investigated. Therefore, the Na+/K+-ATPase (NKA) was pharmacologically inhibited with two cardiac glycosides (CGs), ouabain (OUA) and digoxin (DIG), to raise intracellular Na+ without increasing extracellular Na+ levels. Exposure to HS conditions and treatment with both inhibitors resulted in intracellular Na+ accumulation and subsequent phosphorylation of p38/MAPK. The CGs had different effects on intracellular Ca2+ and K+ compared to HS stimulation. Moreover, the osmoprotective transcription factor nuclear factor of activated T cells 5 (NFAT5) was not upregulated on RNA and protein levels upon OUA and DIG treatment. Accordingly, OUA and DIG did not boost nitric oxide (NO) production and showed heterogeneous effects toward eliminating intracellular bacteria. While HS environments cause hypertonic stress and ionic perturbations, cardiac glycosides only induce the latter. Cotreatment of macrophages with OUA and non-ionic osmolyte mannitol (MAN) partially mimicked the HS-boosted antimicrobial macrophage activity. These findings suggest that intracellular Na+ accumulation and hypertonic stress are required but not sufficient to mimic boosted macrophage function induced by increased extracellular sodium availability. Full article
(This article belongs to the Collection Feature Papers in ‘Cellular Immunology’)
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