Superoxide Dismutase Enzyme Activity Research Articles

Zn(II) enhances the antimicrobial effect of chloroxine and structural analogues against drug-resistant ESKAPE pathogens in vitro

The emerging antibiotic-resistant bacteria, especially the “ESKAPE” pathogens, pose a continuous threat to global health. In this study, we explored metalloantibiotics as promising therapeutics and innovative antimicrobial agents. The role of metal in the antimicrobial activity of chloroxine (5,7-dichloro-8-hydroxyquinoline), as a metalloantibiotic, was investigated by minimal inhibit concentration (MIC) assay and a series of assays, including growth curve, time-killing, and UV–visible spectroscopy and PAR (4-(2-pyridylazo)-resorcinol) competition assays. Both chloroxine and its structural analogues exhibited increased antibacterial potency against Gram-positive bacteria compared to Gram-negative bacteria. The introduction of exogenous manganese or zinc ions significantly boosted chloroxine’s antibacterial efficacy against Gram-negative bacteria, including the notorious ESKAPE pathogens. However, the enhanced antibacterial activity induced by zinc ions could be negated in the presence of copper or ferrous iron ions, as well as changes in oxygen availability, highlighting the involvement of proton motive force, oxidative and antioxidative systems. Notably, chloroxine effectively inhibited the enzymatic activity of superoxide dismutase (SOD). In addition, chloroxine could reverse polymyxin and carbapenem resistance in E. coli in vitro. Therefore, these results suggested that chloroxine with zinc ions are promising therapeutics and antibiotics potentiator to combat multidrug-resistant ESKAPE pathogens

Postharvest application of sodium nitroprusside improves the quality of ‘Umran’ ber fruit under cold storage conditions by regulating enzyme activities

ABSTRACT Ber fruit is highly perishable, with a storage life of only 3–5 days under ambient conditions, which makes it difficult to transport the fruit even to domestic markets. An experiment was conducted to study the effect of postharvest treatment with sodium nitroprusside (50, 100 and 150 µM) on the storage life, quality attributes, bioactive composition and antioxidant enzyme contents of ‘Umran’ ber fruit. The treated fruit were stored for 28 days to investigate the effects of sodium nitroprusside after 7 days of cold storage at 7.5°C and 90–95% RH. It was found that fruit treated with 100 μM sodium nitroprusside experienced lower fruit weight loss and spoilage, maintained fruit firmness, and had a higher sensory quality, phenolic content, carotenoid content, soluble solids content, sugar content, ascorbic acid and antioxidant activity than the control. Furthermore, the activities of the cell wall degrading enzymes polygalacturonase, polyphenol oxidase, pectin methyl esterase and catalase were lower, while the activities of superoxide dismutase and peroxidase enzymes were higher in the treated fruit. Therefore, treatment with 100 μM sodium nitroprusside shows high potential for improving the storage life and maintaining the quality attributes of ber fruit for up to 21 days under cold storage.

Application of Silicon Iron and Silver Nanoparticles Improve Vegetative Development and Physiological Characteristics of Boysenberry Plants Grown under Salinity Stress In Vitro Cultivation Conditions

Salinity is one of the most important abiotic stress factors that affect plant growth and limit agricultural productivity. In this study, the effects of iron (FeNP), silver (AgNP), and silicon dioxide (SiNP) nanoparticles on the morphological and physiological parameters of in vitro boysenberry plants grown under salinity stress (NaCl) were investigated. According to our study results, higher values were obtained from SiNP application in terms of shoot development parameters; FeNP application was found to be more successful for root development; AgNP application was effective in terms of SPAD, leaf relative water content (LRWC), and relative growth rate (RGR); and FeNP application increased superoxide dismutase (SOD) and catalase (CAT) enzyme activities. Salt stress significantly affected root development, SPAD values, LRWC and RGR, and SOD and CAT enzyme activities. As a result, under salt stress conditions, SiNP, FeNP, and AgNP applications can significantly reduce the negative effects of stress and promote the vegetative development of the plant compared to control conditions.

Phytotoxicity Stress Induced by Allelochemicals from Foliar Spray of Sida cordifolia Methanol Leaf Extract on Ageratum conyzoides and Oryza sativa

Allelochemicals are key inhibitors that induce chemical stress in plants. Their mechanisms as agents of oxidative stress are not well understood. A field study was conducted to evaluate herbicidal potential of Sida cordifolia methanol leaf extract (SCLE) on Ageratum conyzoides and Oryza sativa (weedy rice). SCLE concentrations of 0, 3, 6 and 9 g L-1 were prepared and sprayed twice at 7 days interval. The results showed that the SCLE significantly (p<0.05) affected growth attributes, chlorophyll pigments, and proline, and catalase, superoxide dismutase and peroxidase enzyme activities in a concentration-dependent pattern. It was found that high concentrations of SCLE induced greater phytotoxicity against A. conyzoides compared to O. sativa. SCLE spraying stimulated production of reactive oxygen species, boosting their ability to cause damage and inhibit growth. The allelochemicals in the extract stimulated an increased in the level of proline, which is an indicator of oxidative stress. Understanding the physiological and biochemical responses to Sida extract can improve our knowledge on allelochemical target sites and help us to explicate the mechanisms of action of such compounds.

Immune protective, stress indicators, antioxidant, histopathological status, and heat shock protein gene expression impacts of dietary Bacillus spp. against heat shock in Nile tilapia, Oreochromis niloticus

This research evaluated the efficacy of mixed Bacillus strains probiotic supplements in mitigating acute thermal-induced stress in Nile tilapia (Oreochromis niloticus). Three experimental fish groups involved 135 Nile tilapia (49 ± 2 g); one control (no added probiotics), 0.5, and 1% of selected Bacillus strains (B. subtilis, B. licheniformis, and B. pumilus) for 58 days. After the feeding period, growth parameters, immunological parameters, stress biochemical markers, and antioxidant parameters in addition to genes related to stress and histopathological changes in fish, were assessed; subsequently subjected to heat shock at 36 ± 0.5 ◦C for 2 h. Before the heat challenge, our results exhibited a marked increase in the growth efficacy (P < 0.05), lower marked serum levels of triglycerides and cholesterol, and tissue malondialdehyde (MDA) levels along with significantly increased superoxide dismutase (SOD) and catalase (CAT) enzymes activity in fish-fed Bacillus probiotic at 0.5% concerning the control group (P < 0.05). There were no significant changes in the serum levels of glucose, cortisol, lactate, phagocytic activity, respiratory burst (ROS), total immunoglobulin Ig, alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), total protein, albumin, globulin, uric acid, urea, creatinine, as well as HSP70, GST, and GPx mRNA expression in most of the probiotic groups compared to the control group (P > 0.05). When Nile tilapia was exposed to heat stress, supplementation with Bacillus probiotic in the diet significantly decreased most of the indices related to serum biochemical (ALT (P < 0.01; P < 0.001), AST (P < 0.01), LDH (P < 0.01), urea (P < 0.05), and creatinine (P < 0.01)), triglycerides (P < 0.001; (P < 0.01)), cholesterol (P < 0.01; (P < 0.05)), glucose (P < 0.001), and cortisol (P < 0.01; (P < 0.05)), with tissue oxidative stress MDA levels (P < 0.05), and HSP70 mRNA expression (P < 0.01; P < 0.001), aligned with the stressed control group. In addition, a notable upsurge in the total protein, albumin, globulin, phagocytic and ROS activities, and total Ig, as well as the enzymatic antioxidant ability (SOD, CAT) (P < 0.01), with GST and GPx mRNA expression (P < 0.05; P < 0.01), were shown in fish-fed Bacillus spp. post-exposure compared with the stressed control group. Besides, no histopathological alterations were revealed in the spleen and brain of fish pre- and post-heat exposure. According to our findings, diet supplementation of Bacillus species has the potential to combat the suppressive effects of heat shock in Nile tilapia.

Ficus carica Puree Exerts a Higher Antioxidative Profile in Hypoxic Lungs after Intermittently Inducing Hypoxia in Sprague–Dawley Rats

Abstract Background: The body produces more hypoxia-inducible factor and reactive oxygen species in response to hypoxic situations because they cause unbalanced oxygen levels. Ficus carica provides numerous benefits because of its high antioxidant and mineral content. Nevertheless, the mechanism by which F. carica consumption confers this protective benefit remains incompletely understood. Aim: This study aimed to evaluate how F. carica puree (FCP) can affect the antioxidant enzyme activity and malondialdehyde (MDA) levels in the lung by mitigating the effects of intermittent hypoxia (IH). Methods: Thirty Sprague–Dawley rats were divided into five groups negative control (NC), untreated; positive control (PC), treated with aquadest; FCP1; FCP2; and FCP3, which received FCP at doses of 1.25, 2.5, and 5 mL/200 g body weight. The treatment was administered for 4 weeks before inducing IH (10% O2 and 90% N2) into all groups (except NC) for 4 h for 7 days. Furthermore, hemoglobin (Hb) level, lung MDA level, and lung superoxide dismutase (SOD) enzyme activity were assessed. Results: The Hb level did not exhibit a significant increase under IH conditions. Conversely, the PC group exhibited the least activity of lung antioxidant enzymes and the highest lung MDA levels. In addition, the FCP intervention group exhibited lower MDA levels than the PC group and ameliorated relative lung weight loss. Conclusion: All FCP intervention groups showed lower MDA levels and higher SOD levels compared to the PC group, suggesting that FCP could mitigate the effects of hypoxia in rat lungs.

The Haematotoxicity and Nephrotoxicity Effects of Diazepam Administration in Male Albino Rats

Objectives: This study aimed to assess the haematological and nephrotoxic effects of diazepam at varying doses in male albino rats. Materials and Methods: Rats were administered therapeutic (0.062 mg/kg/day), high (0.33 mg/kg/day), and extremely high (0.661 mg/kg/day) doses of diazepam orally for 14 and 28 days. Blood and kidney samples were collected for haematological and biochemical analysis.Results: Diazepam administration significantly reduced red blood cell count (RBC), packed cell volume (PCV), and platelet count (PLT), while other haematological indices were not notably affected. Plasma creatinine and urea levels increased, and total protein decreased across all doses. The treatment also elevated renal thiobarbituric acid reactive substances (TBARS) levels, while reducing antioxidant enzyme activity superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH). Conclusions: Diazepam poses significant risks of oxidative stress, haematotoxicity, and nephrotoxicity. While effective in managing anxiety, caution is necessary due to its potentially harmful effects on blood and renal function.

Effects of Taurine and Enzymatic Cottonseed Protein Concentrate Supplementation in Low-Fishmeal Diet on Growth, Liver Antioxidant Capacity, and Intestinal Health of Golden Pompano (Trachinotus ovatus)

This study was conducted to investigate the impacts of the dietary addition of taurine and enzymatic cottonseed protein concentrate (ECPC) in low-fishmeal diet on the growth performance, plasma biochemical indices, hepatic antioxidant capacity, intestinal anti-inflammatory capacity, intestinal microflora, and muscle quality of golden pompano (Trachinotus ovatus). A total of three isonitrogenous diets were given to 225 golden pompanos (5.6 ± 0.14 g). They were randomly divided into nine cages (1.0 m × 1.0 m × 1.5 m; three cages per treatment) with equal stocking numbers of twenty-five fish per cage. The results indicated that the CSM-TC group significantly increased the growth performance of juvenile T. ovatus (p &lt; 0.05). The results indicated that compared with other groups, the addition of 1% ECPC and 0.25% taurine has been found to enhance the WGR (weight gain rate), SGR (specific growth rate), and CF (condition factor). Compared with other groups, the relative expressions of GH, GHR1, GHR2, IGF1, IGF2, and MyoG were significantly higher in fish fed with CSM-TC. The results showed that CSM-TC significantly increased the activities of alkaline phosphatase, complement 3, and complement 4 enzymes (p &lt; 0.05). The results showed that dietary CSM-TC increased the activities of hepatic superoxide dismutase and total antioxidant capacity enzymes. Compared with other groups, the hepatic relative expressions of Nrf2, HO-1, and GSH-Px were significantly higher in fish fed with CSM-TC. The results showed that dietary CSM-TC increased the activities of intestinal chymotrypsin, lipase, and α-amylase enzymes. A CSM-TC diet significantly increased the relative expressions of IL-10, ZO-1, Occludin, Claudin-3, and Claudin-15 (p &lt; 0.05). The results showed that CSM-C significantly increased the index of Ace and Chao1 (p &lt; 0.05). In conclusion, a high-fermented cottonseed meal diet can have detrimental effects on physiological health in golden pompano, while adding 1% ECPC and 0.25% taurine can improve hepatic and intestinal health via attenuating inflammation and oxidative stress.

Effects of silybin on growth performance, antioxidant capacity and immunity in juvenile hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂) fed with high-lipid diets

This research examined the impacts of varying silybin dosages in high-lipid diets on the growth, hepatic histology, immunity, and immune-related gene expression of juvenile hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂). The grouper (with an initial body weight of 8.27 ± 0.08 g) were fed diets containing silybin at levels of 0 g/kg (S1, control group), 0.05 g/kg (S2), 0.10 g/kg (S3), 0.15 g/kg (S4), 0.20 g/kg (S5), 0.25 g/kg (S6), and 0.50 g/kg (S7) for 8 weeks. The study results suggest that the silybin-treated groups displayed an initial increase followed by a decrease in final body weight and specific growth rate, with the highest value observed in the group S5. In serum samples, silybin supplementation of high-lipid diets resulted in increased activities of alkaline phosphatase (AKP), superoxide dismutase (SOD) and catalase (CAT) enzymes, decreased activities of aspartate transaminase (AST) and alanine transaminase (ALT) enzymes and increased total antioxidant capacity (T-AOC) content. In liver, the addition of silybin to high-lipid diets increased SOD, CAT, and lysozyme (LYZ) enzyme activities, increased T-AOC and immunoglobulin M (IgM) contents, and decreased reactive oxygen species (ROS) and malondialdehyde (MDA) contents. Contrasted with the control group, the addition of silybin at 0.05–0.50 g/kg enhanced the hepatic histomorphology, for example, ameliorating the indistinctness of cell outlines and diminishing the hepatocyte vacuolation. Silybin treatment significantly upregulated the expression of liver sod, cat, gpx, nrf2, keap1, hsp70, hsp90, tlr22, myd88, il-1β, tnf-α and il-6(P < 0.05). Silybin treatment significantly upregulated the expression of tlr22, myd88, il-1β, tnf-α, and il-6 of head kidney (P < 0.05). After vibrio harveyi challenge, groups S5-S6 showed higher survival than the control. Incorporating silybin into high-lipid diets boosts grouper's growth, antioxidant, and immune abilities. Regression analysis implies adding 0.23 g/kg silybin to the diets of juvenile hybrid grouper.

CuO nanoparticles for glioma treatment in vitro and in vivo.

Glioma is the most prevalent malignant brain tumor in adults. The development of engineered nanomaterials (ENMs) has led to the emergence of innovative therapeutic strategies for gliomas. Therefore, our aim is to investigate the therapeutic effect of CuO nanoparticles (NPs) on glioma and provide data support for future research. The therapeutic effect of CuO NPs on glioma rats was explored through the detection of inflammatory factors, oxidase, pathological sections, immunofluorescence, neurotransmitter, glioma biomarker proteins and genes, and rat behavioral tests. Additionally, the application prospect of CuO NPs was evaluated by treating U87MG human glioma cell line. In this study, it was found that CuO NPs can alleviate the inflammatory reaction in the hippocampus tissue of glioma rats, promote the production of ·OH and lead to the up-regulation of catalase (CAT) and superoxide dismutase (SOD) enzyme activities. Treatment with CuO NPs also inhibited the expression of matrix metalloproteinase-9 (MMP-9) biomarkers in model rats and glioma cells. Moreover, it enhanced the release of neurotransmitters, which subsequently improved spatial recognition and memory ability of glioma rats. In conclusion, CuO NPs is a potential glioma treatment for ENMs, but still needs modification and modification strategies to improve its biocompatibility and targeted delivery.

Tert-Butylhydroquinone alleviates a postharvest pericarp browning of longan fruit by regulating antioxidant metabolism.

Harvested longan fruit is prone to pericarp browning, which restricts preservation quality and shortens fruit shelf life. The antioxidant system can defend against oxidative stress-mediated quality deterioration such as fruit browning. This study aimed to evaluate the effect of tert-butylhydroquinone (TBHQ) on anti-browning ability of longan fruit in association with redox metabolism. The results indicated that the application of 0.02% TBHQ significantly suppressed the progression of pericarp browning. In comparison with control, TBHQ treatment decreased the contents of hydrogen peroxide (H2O2), superoxide radical (O2 -⋅), and malondialdehyde, and retained high levels of ascorbic acid (AsA), glutathione (GSH), total phenolics as well as 1,1-diphenyl-2-picrylhydrazyl scavenging rate. Enhanced enzymatic activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR), monodehydroascorbate reductase, and dehydroascorbate reductase (DHAR), but decreased activities of polyphenol oxidase and peroxidase were also observed in TBHQ-treated fruit. Gene expression analysis indicated that redox metabolism-related genes, including DlSOD, DlCAT, DlGR, and DlAPX, were upregulated after TBHQ treatment. Correlation analysis suggested that antioxidants, including AsA, GSH, CAT, APX, SOD, and DHAR, were negatively correlated to reactive oxygen species production and percarp browning. These results suggest that TBHQ is effective in alleviating pericarp browning by increasing antioxidant capacity of longan fruit.

Impact of Zinc oxide nanoparticles on biosynthesis of Thymoquinone in cell cultures of Nigella sativa

The rising market interest for Nigella sativa (Black seeds) necessitates the development of cultivation strategies to enhance metabolites production. Zinc oxide nanoparticles (ZnO-NPs) have drawn global attention as efficient and bio safe elicitors for in vitro cultures, to enhance secondary metabolites production in medicinal plants. In this study, ZnO-NPs were utilized for establishment of callus and cell cultures in black seeds for the first time. Hypocotyl explants were cultured on Murashige and Skoog (MS) media with varying levels of ZnO-NPs, resulted in callus induction and biomass formation. Optimal response in callus growth parameters were observed when explants were grown on MS media supplemented with 60mg/L ZnO-NPs, resulting in 71.2% callus induction frequency, 28.2g/L fresh biomass, 9.7g/L dry biomass, and 63% water content. A substantial increase in callus growth was observed when ZnO-NPs were combined with 6-Benzylaminopurine (BA) at ratio of 45:1.5mg/L, resulting in 91.2% callus induction frequency and 42.2g/L fresh biomass. In cell suspension cultures, ZnO-NPs alone at 45mg/L produced optimum callus biomass (60.9g/L). However, in combination with BA, callus biomass did not increase significantly in cell cultures. Maximum accumulation of total phenolic content (TPC: 26.8mg GAE/g DW; Gallic acid equivalent dry weight) and total flavonoid content (TFC: 19.5mg QE/g DW; Quercetin equivalent dry weight) was observed in cell cultures treated with higher concentration (70mg/L) of ZnO-NPs in the 5th week of the growth curve. Moreover, ZnO-NPs incremented substantially the Phenylalanine lyase (PAL), Superoxide dismutase (SOD) and Peroxidase (POD) enzyme activities in cell cultures. Nonetheless, Reverse Phase High Performance Liquid Chromatography (RP-HPLC) analysis indicated peak production of tymoquinone (168.5mg/g FW) in cell cultures treated with 45mg/L ZnO-NPs alone. This study offers a promising approach for commercial production of Nigella sativa biomass and bioactive metabolites.

Aloe ferox leaf gel extracts attenuate redox imbalance in oxidative renal injury and stimulates glucose uptake, whilst inhibiting key enzymes linked to diabetes and obesity

The worldwide prevalence of diabetes and obesity is growing rapidly. Both metabolic disorders are linked to chronic adverse complications, which include kidney dysfunctions. Medicinal plants play a crucial role in traditional healthcare, especially in developing countries. Aloe ferox, native to South Africa, has a long history of medicinal use, but its pharmacological potential is less studied compared to other Aloe species, necessitating further investigation. Therefore, the present study was conducted to determine the antioxidative, anti-obesogenic, and antidiabetic effects of A. ferox leaf gel extracts using in vitro, ex vivo, and in silico experimental models, with oxidative renal damage induced by ferrous sulfate (FeSO4). A. ferox leaf gel extracts exhibited strong antioxidant activity, inhibited digestive enzymes, and significantly improved glucose uptake. The aqueous extract demonstrated better antioxidant efficacy, leading to higher reduced glutathione (GSH) level, and superoxide dismutase (SOD) and catalase enzymes activity, along with a concurrent reduction of nitric oxide (NO) and malondialdehyde (MDA) levels. Likewise, the aqueous extract showed more potent in vitro DPPH, NO, and OH• radical scavenging activity with IC50 values of 3.64 ±0.3 μg/mL, 110.73±0.1 μg/mL, and 331.13 ±0.7 μg/mL, respectively. The aqueous extract had better inhibition of the enzyme α-amylase (IC50 = 25.73±2.5 µg/mL), whilst the ethanolic extract inhibited α-glucosidase (IC50 =663.2±0.3 µg/ml), and pancreatic lipase (IC50 =122.01±5.9 µg/mL) more strongly. Incubation of the extracts with yeast cells stimulated glucose uptake dose dependently, when ethanolic extract (IC50 = 308.01±0.7 µg/mL) showed the better activity compared to the aqueous extract (IC50 = 338.79±7.05 µg/mL). Furthermore, LC-MS analysis led to the identification of many compounds, when chlorogenic acid demonstrated a stronger molecular interaction with the active site amino acids of α-amylase and catalase compared to other compounds. However, Aloin B showed the highest affinity with α-glucosidase and 5-Hydroxyaloin A showed the lowest binding energy with lipase, and SOD enzyme. These results suggest the reno-protective effects of A. ferox leaf gel extracts against FeSO4-induced oxidative stress along with its anti-hyperglycaemic activity. Given these observed effects, A. ferox leaf gel could indeed be valuable in developing natural therapies and potential drug development for the management of these disorders. Further studies in animal models are needed to ascertain the results of this study.

Biochemical and Proteomic Analyses in Drought-Tolerant Wheat Mutants Obtained by Gamma Irradiation.

The bread wheat cultivar (Triticum aestivum L. cv. Sagittario) as a parental line and its mutant, drought-tolerant lines (Mutant lines 4 and 5) were subjected to polyethylene glycol (PEG)-induced drought. Drought stress resulted in decreased chlorophyll levels and the accumulation of proline and TBARS, despite increases in activities of catalase, peroxidase, and superoxide dismutase enzymes. Transcription of the genes encoding these enzymes and delta-1-pyrroline 5-carboxylase synthetase was induced by drought. 2-DE gel electrophoresis analysis identified differentially expressed proteins (DEPs) in the mutant lines, which are distinguished by "chloroplast", "mitochondrion", "pyruvate dehydrogenase complex", and "homeostatic process" terms. The drought tolerance of the mutant lines might be attributed to improved photosynthesis, efficient ATP synthesis, and modified antioxidant capacity. In addition to proteomics data, the drought tolerance of wheat genotypes might also be assessed by chlorophyll content and TaPOX gene expression. To our knowledge, this is the first proteomic analysis of gamma-induced mutants of bread wheat. These findings are expected to be utilized in plant breeding studies.

Study on sperm cryopreservation of hybrid fish derived from Carassius cuvieri (♀) × Carassius auratus red var (♂)

Cryopreservation of sperm is an effective method for conserving germplasm resources in fish genetic breeding. The high-quality hybrid fish (WR) derived from white crucian carp (Carassius cuvieri, WCC, ♀) and red crucian carp (C. auratus red var., RCC, ♂), possesses valuable traits such as high survival rates, strong resistance, and rapid growth, representing an important germplasm resources of crucian carp. This study compared the effects of different antifreeze solutions on sperm viability among three varieties (WR, WCC, and RCC) and examined changes in enzyme activity, fertilization rates, and hatching rates after cryopreservation, aiming to enhance the cryogenic sperm cryopreservation technique in hybrid fish and investigate the mechanisms underlying spermatozoa damage caused by cryopreservation. The results showed that the antifreeze combination of D14 with 15 % dimethyl sulfoxide (DMSO) had the best effect in preserving the sperm of WR and WCC, while D20 with 10 % DMSO was the optimal combination for RCC sperm. After ultra-low temperature preservation, the longevity, fertilization, and hatching rates of frozen sperm were significantly lower (P < 0.05) compared to fresh sperm. The enzyme activities of superoxide dismutase (SOD), lactate dehydrogenase (LDH), and creatine kinase (CK) were significantly decreased (P < 0.05) in spermatozoa, whereas they showed a significant increase (P < 0.05) in sperm plasma. Succinate dehydrogenase (SDH) activity was significantly reduced (P < 0.05) in frozen spermatozoa of RCC compared to fresh spermatozoa, and exhibited lower activity in frozen spermatozoa of WCC and WR. Additionally, SDH activity was significantly elevated (P < 0.05) in frozen sperm plasma, and glutathione reductase (GR) activity was significantly lower (P < 0.05) in both frozen sperm plasma and spermatozoa across all three species. The study demonstrated that cryopreservation had a significant effect on the enzyme activities of spermatozoa and sperm plasma in all three species. These findings provide important technical support for the conservation of high-quality fish germplasm resources, particularly for novel varieties resulting from distant hybridization in fish.

The research of nicotinamide and β-arbutin on reducing melanin content in the skin of leopard coral grouper (Plectropomus leopardus)

Body color is an important economic characteristic of leopard coral grouper (Plectropomus leopardus). In this study, we tried to make the red color more visible on the skin by reducing the melanin level, and aimed to investigate the possible mechanism of nicotinamide and β-arbutin on reducing melanin content in the skin of P. leopardus. 0.5 % nicotinamide or 0.5 % β-arbutin was added to the basal feed formulation to feed P. leopardus for 60 days. After nicotinamide or β-arbutin added feeding, the time for P. leopardus to maintain uniform body color was significantly longer. The melanin content in the skin of P. leopardus was significantly reduced, and the number of melanin particles was reduced. In skin, the enzyme activities of superoxide dismutase (SOD) and catalase (CAT) decreased, and the content of malondialdehyde (MDA) increased. The mRNA expression of TYR, Sox10 and Mitf related to melanin synthesis and proliferation and differentiation decreased. The apoptosis-related gene Bax was upregulated, the Bcl-2 gene was down-regulated, and Bax/Bcl-2 > 1. The content of tyrosinase decreased and the content of melanin metabolizing enzyme increased, and the effect of nicotinamide was more obvious than that of β-arbutin. In summary, nicotinamide or β-arbutin added feeding increased the oxidative stress and the apoptosis level of the skin, increased the metabolism of melanin, decreased the synthesis and differentiation of melanin, thus reduced the content of melanin and the number of melanin particles in the skin. This study provided a new basis for the body color regulation of cultured P. leopardus.

Protective Effect of Epigallocatechin-3-gallate against Hepatic Oxidative Stress Induced by tert-Butyl Hhydroperoxide in Yellow-Feathered Broilers.

Recent studies have shown that epigallocatechin-3-gallate (EGCG), as an effective antioxidant, could attenuate the oxidative damage, inflammation and necrosis in the liver in response to oxidative stress. The present study investigated whether oral administration of EGCG could effectively alleviate the hepatic histopathological changes and oxidative damage in yellow-feathered broilers induced by tert-butyl hydroperoxide (t-BHP). Broilers were exposed to 600 μmol t-BHP/kg body weight (BW) to induce oxidative stress by intraperitoneal injection every five days, followed by oral administration of different doses of EGCG (0, 20, 40 and 60 mg/kg BW) and 20 mg vitamin E (VE)/kg BW every day during 5-21 days of age. The results showed that t-BHP injection decreased (p < 0.05) body weight and the relative weight of the spleen; the enzyme activities of total antioxidant capacity (T-AOC), catalase (CAT) and total superoxide dismutase (SOD); and gene mRNA expressions of nuclear factor erythroid 2-related factor 2 (Nrf2), CAT, SOD1, SOD2 and acetyl-CoA carboxylase (ACACA); as well as increased (p < 0.05) necrosis formation, malondialdehyde (MDA) content, reactive oxygen species (ROS)accumulation, and peroxisome proliferator activates receptor-α (PPARα) mRNA expression in the liver of yellow-feathered female broilers at 21 days of age. Treatment with 60 mg EGCG/kg BW orally could enhance antioxidant enzyme activities and reverse the hepatic damage induced by t-BHP injection by reducing the accumulation of ROS and MDA in the liver and activating the Nrf2 and PPARα pathways related to the induction of antioxidant gene expression (p < 0.05). In conclusion, intraperitoneal injection of t-BHP impaired body growth and induced hepatic ROS accumulation, which destroyed the antioxidant system and led to oxidative damage in the liver of yellow-feathered broilers from 5 to 21 days of age. It is suggested that EGCG may play an antioxidant role through the Nrf2 and PPARα signaling pathways to effectively protect against t-BHP-induced hepatic oxidative damage in broilers, and the appropriate dose was 60 mg EGCG/kg BW by oral administration.

Reno‐protective potential of sudachitin to mitigate paraquat instigated renal toxicity via regulating Nrf2/Keap1 pathway: An inflammatory, apoptotic and histopathological assessment

This investigation was executed to assess the protective effects of SCN to counteract PQ instigated renal damage in albino rats (Rattus norvegicus). Twenty‐four rats were apportioned in 4 different groups i.e., a control group, PQ (5mg/kg) intoxicated, PQ (5mg/kg) + SCN (20mg/kg) exposed &amp; SCN (20mg/kg) only administrated group. Our findings explored that exposure to PQ lessened the expressions of Nrf2 and its cytoprotective genes while escalating the expression of keap1. Furthermore, PQ intoxication reduced the enzymatic activity of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GSR), &amp; glutathione (GSH), while upregulating the levels of malondialdehyde (MDA) &amp; reactive oxygen species (ROS). Moreover, intoxication to PQ significantly increased the levels of neutrophil gelatinous‐associated lipocalin (NGAL), urea, kidney injury molecule‐1(KIM‐1) as well as creatine while reducing creatine clearance. Additionally, exposure to PQ upregulated the levels of inflammatory markers including interleukin‐6 (IL‐6), tumor necrosis‐ α (TNF‐ α), nuclear factor‐ κB (NF‐κB), interleukin 1beta (IL‐1β), &amp; cyclo‐oxygenase‐2 (COX‐2). Moreover, PQ administration upregulated the expression of Bax and Caspase‐3 while downregulating the expressions of Bcl‐2. Besides, PQ exposure prompted various histopathological damages in renal tissues. Nonetheless, SCN substantially restored aforementioned alterations in renal tissues owing to its anti‐oxidative, anti‐inflammatory and anti‐apoptotic potential.

The effect of eight weeks of endurance training and MitoQ supplementation on antioxidant capacity and the expression of sestrin-2 and AMPK in cardiac tissue of aged rats

PurposeThe present study aimed to investigate the effects of endurance training (ET) in combination with MitoQ supplementation on antioxidant indices and the expression of sesterin-2 (SESN2) as an anti-aging factor and AMPK as an energy sensor in aged male Wistar rats. MethodsTwenty-eight aged Wistar rats (410 ± 15 g, 22 ± 1.5 months old) were randomly divided into four groups (n = 7): Control, ET (eight weeks endurance training on the treadmill), MitoQ (250 μ/L in drinking water), and ET + MitoQ. We measured the protein and gene expression of SESN2 and AMPK in the heart tissue by western blotting and real-time PCR, respectively. In addition, antioxidant indices, superoxide dismutase (SOD), and glutathione peroxidase (GPx) activity, and oxidant malondialdehyde (MDA) concentration in the cardiac tissue and serum were measured. ResultsSESN2 and AMPK protein expression significantly increased in the MitoQ group compared to the control group (P = 0.002, P = 0.0003). MDA content in tissue and serum remained unchanged in all groups (P > 0.05). MitoQ supplementation significantly increased SOD and GPx enzyme activity in serum and cardiac tissue (P = 0.001). ConclusionOverall, ET and MitoQ alone and in combination have anti-aging effects and improve the expression of AMPK and SESN2. Additionally, ET and MitoQ lead to improved antioxidant capacity in aged rats by ameliorating the activity of antioxidant enzymes.

Establishment and identification of the gill cell line from the blunt snout bream (Megalobrama amblycephala) and its application in studying gill remodeling under hypoxia.

To probe the mechanisms of gill remodeling in blunt snout bream under hypoxic conditions, we selected gill tissue for primary cell culture to establish and characterize the first blunt snout bream gill cell line, named MAG. The gill cells were efficiently passaged in M199 medium supplemented with 8% antibiotics and 15% fetal bovine serum at 28°C, exhibiting primarily an epithelial-fibroblast mixed type. Additionally, the MAG cells (17th generation) were subjected to four experimental conditions-normoxia, hypoxia 12h, hypoxia 24h, and reoxygenation 24h (R24h)-to evaluate the effects of hypoxia and reoxygenation on MAG cells during gill remodeling. We found that the MAG cell morphology underwent shrinkage and mitochondrial potential gradually lost, even leading to gradual apoptosis with increasing hypoxia duration and increased reactive oxygen species (ROS) activity. Upon reoxygenation, MAG cells gradually regain cellular homeostasis, accompanied by a decrease in ROS activity. Analysis of superoxide dismutase (SOD), glutathione (GSH), lactate dehydrogenase (LDH), catalase (CAT), anti-superoxide anion, and other enzyme activities revealed enhanced antioxidant enzyme activity in MAG cells during hypoxia, aiding in adapting to hypoxic stress and preserving cell morphology. After reoxygenation, the cells gradually returned to normoxic levels. Our findings underscore the MAG cells can be used to study hypoxic cell apoptosis during gill remodeling. Therefore, the MAG cell line will serve as a vital in vitro model for exploring gill remodeling in blunt snout bream under hypoxia.