Liver Antioxidant Enzyme Activities Research Articles

Leaf extract of Momordica charantia: Effects on liver enzymes, duodenum antioxidant enzymes, and disaccharidases with liver and duodenum histology

Background: Momordica charantia (MC) plant rich in phytochemicals, promoting sound health conditions, contains nutritional and nutraceutical components. Its popular in traditional and folk’s medicine, extract is used to treat and remedy diseases. Adverse effects produce toxic symptoms in children and laboratory animals. Aims and Objectives: The study investigated activities of liver enzymes, antioxidant enzymes, and disaccharidases in the duodenum and evaluated the histomorphological changes in the duodenum and liver of normal rats orally administered with aqueous leaf extract of MC. Materials and Methods: Fifteen male Wistar rats weight between 150 g and 200 g used for this experiment were divided into three groups equally. Group A received only water and Groups B and C received 100 and 400 mg/kg body weight of extract orally for 21 days. Liver enzymes, duodenum antioxidant enzymes, and disaccharidases were determined using standard methods. Histology of duodenum and liver was studied with hematoxylin and eosin staining. Results: Observation from statistically compared results showed that catalase, superoxide dismutase, and glutathione in the duodenum reduced significantly. Malondialdehyde only increases in Group C but not significant. Maltase, sucrose, and lactase in the duodenum reduced significantly. Total protein, albumin, alanine aminotransferase, and aspartate aminotransferase in the liver reduced significantly, alkaline phosphatase showed increase not significant for the two doses (P < 0.05). Histological study from duodenum and liver showed some degenerated villi, loss of epithelial cell, and goblet cells in the duodenum, central vein constriction with hepatocyte hypertrophy, degeneration, and sinusoid dilation. Conclusion: MC has health benefits with ability to neutralized free radicals, preserve functions of liver and if care is not taken, it can induce negative histomorphological changes in the duodenum and the liver.

Adulteration of aquafeed with melamine and melamine‐formaldehyde chemicals; Ex situ study of impact on haematology and antioxidant systems in Clarias gariepinus

Adulteration of aquafeed has raised critical concern regarding quality and safety of aquatic meats. This study assessed the impact of melamine (MEL) and melamine-formaldehyde (MEF) chemicals (adulterants) on haematology, gill and liver antioxidant enzymes activities of Clarias gariepinus. Fish were fed diets contaminated with MEL and MEF at 3.0 g Kg−1 (0.3%) dietary inclusion for 45 days, followed by a depuration trial that lasted for 30 days. Body biomass of MEL- and MEF-treated groups decreased markedly, relative to the control. Haematological parameters such as red blood cell, white blood cell, haemoglobin and packed cell volume contents of the treated groups reduced prominently, while antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) activities were suppressed, particularly in the liver of the treated groups. Additionally, toxicity of MEL and MEF caused significant increase in malondialdehyde (MDA) content in the gill and liver tissues of the exposed groups. However, antioxidant enzymes activities and haematology were restored to the normal physiological condition, during the recovery (depuration) phase. MEL- and MEF-induced toxic effects on the exposed fish and the findings of the current study provides baseline information and insight on the adverse impact of these chemicals in aquatic models.

Short term effect of zinc administration on some biochemical parameters and antioxidant enzymes in albino rats

Zinc is an essential trace element exerting important antioxidant, anti-inflammatory, and apoptotic effects, and is capable of influencing molecular functioin as well as signal transduction. It is used as a supplement for the treatment of diarrhoea. This study was conceived to evaluate the short term effect of zinc administration on some biochemical parameters and antioxidant enzymes in albino rats. Sixteen (16) albino rats (both sexes) were allocated randomly into four experimental groups of four rats each. One group served as the control and were given distilled water. The three experimental groups were administered with 10, 20 and 40 mg/kg body weight of Zn respectively for 14 consecutive days. The animals were sacrificed on the 15th day and blood was collected for liver and kidney function parameters, antioxidant enzymes activities and malondialdehyde concentration using standard procedures. The concentrations of alkaline phosphatase (ALP) and alanine aminotransferase (ALT) significantly increase (p &amp;lt; 0.05) while aspartate transferase (AST) significantly decreased in a dose dependent manner when compared with the control group. There was a significant decrease (p &amp;lt; 0.05) in creatinine, a significant increase in potassium and no significant difference in serum urea level when compared with the control group. The activities of glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase significantly increased while MDA significantly decreased when compared with the control group. Increase in ALT suggests an improvement in the activities of these enzymes while increased potassium level is an indication of kidney dysfunction. Increased antioxidant enzymes and decreased MDA may suggest that zinc improved antioxidant status and decrease free radical generation. From the study, it may be suggested that zinc improved the activities of liver biomakers and antioxidant enzymes. It is therefore recommended that more studies be carried out in establishing the effect of zinc for prolonged usage, at larger doses on other organs.

Curcumin protects against Aflatoxin B1-induced liver injury in broilers via the modulation of long non-coding RNA expression

Aflatoxin B1 (AFB1) is a potent hepatotoxic and carcinogenic agent. Curcumin possesses potential anti-inflammatory, anti-oxidative and hepatoprotective effects. However, the role of LncRNAs in the protective mechanisms of curcumin against AFB1-induced liver damage is still elusive. Experimental broilers were randomly divided into 1) control group, 2) AFB1 group (1 mg/kg feed), 3) cur + AFB1 group (1 mg/kg AFB1 plus 300 mg/kg curcumin diet) and 4) curcumin group (300 mg/kg curcumin diet). Liver transcriptome analyses and qPCR were performed to identify shifts in genes expression. In addition, histopathological assessment and oxidant status were determined. Dietary AFB1 caused hepatic morphological injury, significantly increased the production of ROS, decreased liver antioxidant enzymes activities and induced inflammation and apoptosis. However, dietary curcumin partially attenuated the abnormal morphological changes, oxidative stress, and apoptosis in liver tissues. Transcriptional profiling results showed that 34 LncRNAs and 717 mRNAs were differentially expressed with AFB1 and curcumin co-treatment in livers of broilers. Analysis of the LncRNA-mRNA network, GO and KEGG enrichment data suggested that oxidative stress, inflammation and apoptosis pathway were crucial in curcumin’s alleviating AFB1-induced liver damage. In conclusion, curcumin prevented AFB1-induced oxidative stress, inflammation and apoptosis through LncRNAs. These results provide new insights for unveiling the protective mechanisms of curcumin against AFB1-induced liver damage.

Annona senegalensis extract demonstrates anticancer properties in N-diethylnitrosamine-induced hepatocellular carcinoma in male Wistar rats

BackgroundHepatocellular carcinoma (HCC) is a common and leading cancer around the globe. This study investigated the anticancer properties of extract of Annona senegalensis in N-diethylnitrosamine (DEN) - induced hepatocellular carcinoma in male Wistar rats. MethodsRats were simultaneously induced with a combination of 100 mg/kg b.wt of DEN and 0.5 mL/kg of carbon tetrachloride (CCl4) intraperitoneally once a week for three weeks in a row. Thereafter, animals were treated with 100 mg/kg and 200 mg/kg b.wt of A. senegalensis extract daily for 21days. Analysis using gas chromatography-mass spectrometry (GC–MS) was carried out to discover the phytoconstituents contained in the n-hexane extract of A. senegelensis. The levels of liver function parameters and antioxidant enzyme activities were determined via spectrophotometric analysis. Reverse transcriptase-polymerase chain reaction technique was used to assess the gene expression patterns of BCL-2, P53, P21, IL-6, FNTA, VEGF, HIF, AFP, XIAP, and EGFR mRNAs. ResultsTreatment of DEN-induced hepatocellular carcinoma Wistar rats with the extract caused significant (p < 0.05) decrease in the activities of ALT and AST. It also resulted in a reduction of the concentration of MDA and a significant increase (p < 0.05) in SOD and GSH activities. IL-6, BCL-2, VEGF, EGFR, XIAP, FNTA, and P21 mRNAs expressions were significantly (p < 0.05) downregulated after treatment. Histopathological analysis revealed that the extract improved the liver architecture. ConclusionA. senegelensis n-hexane extract demonstrates its anticancer properties by improving the liver architecture, increasing the antioxidant defense systems, downregulating the pro-inflammatory, anti-apoptotic, angiogenic, alpha-fetoprotein and farnesyl transferase mRNAs expression and hitherto up-regulate the expression of tumor suppressor (P21 and P53) mRNAs.

Enhanced growth performance, muscle quality and liver health of largemouth bass (Micropterus salmoides) were related to dietary small peptides supplementation

To investigate whether incorporation of small peptides into diets could change the growth performance, muscle quality and liver health of the largemouth bass, four diets were designed: SP0+ group (positive control group) was formulated according to the nutritional requirement of the largemouth bass. In SP0− group (negative control group), the crude protein level was decreased by 30 g/kg compared with SP0+ group; SP20 group was added 20 g/kg small peptides based on the SP0− group, and its crude protein level did not reach that of SP0+ group. In SP65 group, 65 g/kg small peptides were added on the basis of SP0− group to obtain same crude protein level as SP0+ group. Fish were fed with these four different diets for 9 weeks. Results showed that, compared with the negative control group, the addition of 20 g/kg small peptides had no significant effect on the weight gain rate and feed coefficient of the largemouth bass; adding 65 g/kg small peptides could significantly increase the weight gain rate and reduce the feed coefficient (p < .05), both reaching the level of the positive control group. Adding 20 g/kg or/and 65 g/kg of small peptides could significantly increase the content of cysteine and proline, the total amino acid, essential amino acid and non-essential amino acid in the muscle (p < .05), as well as fatty acids, especially ARA, EPA and DHA. Adding 20 g/kg or 65 g/kg small peptides to the feed could increase the protease activity of the digestive system and apparent protein digestibility while increasing liver and serum's antioxidant enzyme activity to control the negative effect of MDA. Because total superoxide dismutase and catalase protected fish from oxidation, muscle quality and live health were both improved, consequently enhanced transaminase in the liver and reduced transaminase in the serum were observed.

Determination of Fipronil toxicity by different biomarkers in gill and liver tissue of rainbow trout (Oncorhynchus mykiss).

Insecticides that disrupt the healthy functioning of the ecosystem have toxic potential on non-target organisms. Fish, an important component of the aquatic ecosystem, are exposed to these pesticides in different ways. The stress response is regarded as an adaptive mechanism that allows the fish to cope with the perceived stressor to maintain its normal or homeostatic state. This mechanism is determined by antioxidant parameters and oxidative stress indicators measured in gill and liver tissue of rainbow trout. Accordingly, the effects of fipronil (FP) insecticide on the physiology of rainbow trout (Oncorhynchus mykiss) were determined with using the different biomarkers (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), malondialdehyde (MDA), paraoxonase (PON), arylesterase (ARE), myeloperoxidase (MPO), 8-hydroxy-2-deoxyguanosine (8-OHdG)), and caspase 3 activity) in this study. Different doses of FP inhibited antioxidant enzyme activities in rainbow trout liver and gill tissues while inducing oxidative stress parameter (MDA, MPO, and 8-OHdG) levels. Also, caspase-3 activity was increased in liver and gill tissue, but this increase was statistically significant only in gill tissue (p < 0.05). When the results of the study were taken into consideration, it was concluded that different doses of FP insecticide caused physiological changes in rainbow trout and the studied parameters were usable biomarkers in explaining the adaptive response of stress factor.

Impacts of dietary eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) level and ratio on the growth, fatty acids composition and hepatic-antioxidant status of largemouth bass (Micropterus salmoides)

A ten-week feeding trial was conducted to evaluate largemouth bass (Micropterus salmoides, LMB) responses to supplemental eicosapentaenoic acid (EPA)- and docosahexaenoic acid (DHA)-rich oils at different inclusion levels and ratios. For this purpose, eight experimental diets were formulated to contain 42% crude protein and12% lipid. Two diets were formulated to be n-3 fatty acid (FA) and EPA/DHA depleted and served as negative controls for n-3 FA or EPA + DHA, respectively. Two additional sets of three diets were designed to contain 1 or 2% EPA + DHA and three different EPA:DHA ratios (20:80, 50:50, and 80:20). Each diet was fed to triplicate groups of 15 feed-trained juvenile LMB (13.8 ± 0.2 g initial weight) stocked in 110-L glass aquaria operating as a recirculating aquaculture system. At the end of the feeding trial, the production performance of LMB fed EPA + DHA supplemented diets was unaffected by EPA + DHA levels and ratios. However, LMB fed diets with either 1 or 2% EPA + DHA displayed higher weight gain and feed efficiency compared to those fed un-supplemented diets. HSI was lower groups fed n-3 FA depleted compared to 2% EPA + DHA-fed groups. No significant differences were detected for whole-body proximate composition of LMB; while whole-body EPA and DHA concentrations were significantly affected by diet. Liver antioxidant enzyme activities were unaffected by the dietary supplementation of 1 or 2% EPA + DHA, but liver superoxide dismutase activity was significantly higher in fish fed EPA/DHA depleted diet relative fish fed the n-3 FA depleted and 1% EPA + DHA diets. On the contrary, significantly lower malondialdehyde concentration was observed in the liver of LMB fed the latter relative to fish fed the former diet. Based on the overall findings, LMB appears to be able to synthesize EPA and DHA from linolenic acid to meet physiological needs for adequate production performance and health. Nevertheless, our findings also indicate that both weight gain and feed efficiency, as well as whole-body concentrations of EPA and DHA can be enhanced in LMB by the dietary provision of around 1% EPA + DHA.

Therapeutic Effects of 5,7-Dihydroxy-6-Oxoheptadecanoic Acid on Dysglycemia, Dyslipidemia, and Other Complications in Diabetic Rats

The current study aimed to investigate the therapeutic effects of 5,7-dihydroxy-6-oxoheptadecanoic acid (DHA) from Tiliacora triandra on rat models of type 2 diabetes mellitus (T2DM). T2DM was induced with a combination of high-fat diet/streptozotocin (HFD/STZ), and diabetic rats were treated with DHA (25 mg/kg) for 30 days. The body weight, fasting blood glucose (FBG), serum, and liver biochemical parameters, as well as histological evaluations of the liver and pancreas, were evaluated. Diabetic rats displayed a significant increase in FBG, serum lipid profiles (triglycerides, total cholesterol, and low-density lipoprotein cholesterol), liver function enzymes (aspartate transaminase, alkaline phosphatase, and alanine transaminase), creatinine, liver malondialdehyde (MDA), and myeloperoxidase (MPO) contents. Furthermore, insulin level and liver antioxidant enzyme activities (catalase [CAT], superoxide dismutase [SOD], and glutathione peroxidase [GSH-Px]) were significantly reduced in the diabetic rats. Whereas, treatment with DHA significantly reduced FBG, serum lipids, liver function enzymes, serum creatinine, liver MDA, and MPO contents. In addition, treatment with DHA significantly increased serum insulin level and liver SOD, CAT, and GSH-Px activities. In addition, DHA alleviated histopathological changes in the pancreas and liver caused by T2DM. These results portray the antidiabetic and antioxidative properties of DHA and can be considered as a potential treatment for T2DM.

A combined healthy strategy for successful weight loss, weight maintenance and improvement of hepatic lipid metabolism

Obesity is critically related with the development of metabolic and pathophysiological alterations among which non-alcoholic fatty liver disease (NAFLD) is of especial relevance. Although there are numerous strategies to successfully treat obesity, the prevention of weight regain still remains challenging for individuals who have undergone weight loss programs. In such context, diet and physical activity are considered essential for the regulation of body weight and lipid metabolism. In this study, rats were fed a high-fat diet (HFD) to induce obesity and alterations in hepatic lipid metabolism. Obese rats were then treated with single or combined strategies of caloric restriction, physical exercise, and/or pharmacological treatment with an appetite suppressant, to lose weight, reverse the obesity-related alterations in hepatic morphology and lipid metabolism and maintain the beneficial effects of the interventions used. HFD induced excess body weight, hepatic steatosis, altered fatty acid profile, dysregulated gene expression of lipogenic and lipolytic enzymes, as well as plasma markers of liver damage, and modifications in liver antioxidant enzyme activity. Such alterations were ameliorated by caloric restriction in combination with a mixed training protocol and/or food-intake inhibitor administration during a weight loss intervention period of 3 weeks, and the beneficial effects remained after 6 weeks of weight maintenance, with some interesting interactions observed. In conclusion, weight loss strategies assayed were efficient at correcting the obesogenic action of a HFD and related alterations in hepatic functionality through different molecular mechanisms. The beneficial effects were also evident along the post-intervention maintenance period to avoid body weight regain.

Dietary synbiotic supplementation improves the growth performance, body antioxidant pool, serum biochemistry, meat quality, and lipid oxidative stability in broiler chickens.

The present study investigated the effects of Lactobacillus acidophilus (LBA) and mannan-oligosaccharides (MOS) supplementation on the production performance, serum biochemistry, antioxidant profile, health indices, meat quality, and lipid oxidative stability of broiler chicken. A total of 252 commercial broiler chickens at 1 d old of uniform body weight were randomly allocated to 6 maize-soybean-based dietary treatments: T1 (control diet), T2 ( antibiotic bacitracin methylene di-salicylate [BMD] at 20 mg/kg diet), T3 (MOS at 0.1% + LBA at 106 CFU/g feed), T4 (MOS at 0.1% + LBA at 107 CFU/g feed), T5 (MOS at 0.2% + LBA at 106 CFU/g feed), and T6 (MOS at 0.2% + LBA at 107 CFU/g feed). Each treatment was assigned to 6 replicates of 7 birds. The samples for meat quality and serum biochemistry analysis were taken from 12 birds per treatment (2 birds/replicate). The results revealed better (P < 0.01) growth performance and production efficiency of birds fed either T5 or T6 diet compared to control or BMD supplemented diet and BMD-supplemented birds superseded the control birds. Higher (P < 0.01) serum and liver antioxidant enzyme activities, meat antioxidant capacity (2, 2-azinobis-3-ethylbenzothiazoline-6-sulfonic acid [ABTS] and 1, 1-diphenyl-2-picrylhydrazyl [DPPH] assays], serum total protein, high-density lipoproteins (HDL) cholesterol (P < 0.05), and globulin levels (P < 0.01) were observed in birds fed either T5 or T6 diet compared to control or BMD supplemented birds, whereas, lower lipid oxidation (P < 0.01), cardiac risk ratio, atherogenic coefficient, atherogenic index of plasma, serum glucose, triglyceride, total cholesterol levels (P < 0.01), and serum albumin-to-globulin ratio (P < 0.05) were observed in the chickens. The pH of meat from birds fed T4, T5 or T6 diet was lower (P < 0.01) compared to control and other treatments. The extract release volume (ERV), water holding capacity (WHC), and protein content of meat were higher (P < 0.05) in birds fed either T5 or T6 diet compared to control or BMD supplemented birds. Thus, it was concluded that the supplementation of 0.2% MOS along with LBA at 106 CFU/g is optimum for better growth performance, serum biochemistry, antioxidant profile, health indices, meat quality, and lipid oxidative stability of broiler chickens.

Anti-Inflammatory Activities of Kukoamine A From the Root Bark of Lycium chinense Miller

Kukoamine A (Kuk A) is a naturally occurring bioactive spermine alkaloid found in the root bark of Lycium chinense, and it exerts various therapeutic effects including antioxidant, neuroprotective, anti-inflammatory, and antidiabetic effects. This study evaluated the anti-inflammatory properties of Kuk A against lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophage cells and carrageenan-induced paw edema in rats. Pretreatment of cells with Kuk A significantly inhibited the production of reactive oxygen species, nitric oxide, prostaglandin E2, cyclooxygenase-2 activity, tumor necrosis factor-α, interleukin-1β (IL-1β), and IL-6 in LPS-treated cells. In addition, pretreatment of rats with Kuk A significantly decreased inflammatory response to carrageenan-induced paw edema by alleviating proinflammatory cytokines in the serum, malondialdehyde levels in the liver and increasing the activities of liver antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) of carrageenan-treated rats. These results suggest the protective role of Kuk A in acute inflammatory reaction and could be useful in the treatment of inflammatory-related disorders.

Partial replacement of fish oil with terrestrial lipid blend and effects on growth performance, body composition, immune parameter and growth‐related genes in yellow drum ( Nibea albiflora )

The imbalance of fish oil (FO) supply and demand has motivated efforts to identify an alternative for aqua feed. An 8-week feeding trial was conducted to evaluate the effects of dietary fish oil partial replacement with mixed oil from linseed and lard (1:1) on growth, body composition and immunity when the N3 long-chain polyunsaturated fatty acid (N3 LC-PUFAs) requirement is met for Nibea albiflora. Two types of experimental diets were formulated with 100% fish oil (FO) or 69% mixed oil (Mix). The results indicated that the Mix diet significantly improved the specific growth rate (SGR), weight gain (WG), feed efficiency ratio (FER), muscle tissue growth hormone receptor (GHR), insulin-like growth factor 1 (IGF1) and insulin-like growth factor 1 receptor (IGF1R) gene expression of the yellow drum (p < .05). No significant difference in the survival rate (SR), feed intake (FI), hepatosomatic index (HSI), viscerosomatic index (VSI), condition factor (CF), N3 PUFA percentage, liver antioxidant enzyme activities or pro-inflammatory gene expression was observed between the two treatments. Therefore, terrestrial blend lipid from linseed and lard could be used as an alternative for dietary fish oil without compromising growth performance and immunity for the juvenile yellow drum.

Effects of dietary Origanum vulgare on gilthead seabream (Sparus aurata L.) immune and antioxidant status

Origanum sp. is a very common genus of aromatic plants worldwide distributed around the Mediterranean area and O. vulgare (oregano) is the most important species of this genus throughout the world. Due the known medicinal properties of oregano, the effect of diets enriched with 0% (control), 0.5% and 1% oregano leaves powder was studied on the growth, immune and antioxidant status of gilthead seabream (Sparus aurata L.). Fish fed with oregano 0.5% and 1% enriched diets improved both humoral (IgM and bactericidal activity in skin mucus and protease activity in serum) and cellular (head kidney leucocytes phagocytic ability) immunity at 15 and 30 days. Furthermore, the addition of oregano did not provoke any significant effect neither in the growth promotion nor in the liver antioxidant enzymes activity studied in the serum and skin mucus. The possibility of using O. vulgare as a functional additive to fish diet is discussed.

Evaluation of whey protein sources on performance, liver antioxidants and immune responses of broiler chickens challenged with ethanol.

To evaluate the effects of whey protein (WP) sources on performance, liver antioxidants and immune responses of broiler chickens, 300 one-d-old male Ross 308 chickens were randomly allocated into six treatments with five replications of 10 birds each. This study was conducted on the basis of a completely randomized design in a 3×2 factorial arrangement with dietary supplemental WP sources (no WP; 2% WP and 2% whey protein concentrate (WPC)) and ethanol (zero and 6%) into drinking water. Birds were challenged with ethanol 6% from 10 to 24days of age. Growth performance, immune responses, intestinal morphology and antioxidant enzymes were assessed in both challenged and non-challenged groups. There was a significant interaction between ethanol and WP sources for growth performance, so that weight gain (WG), feed intake (FI) and feed conversion ratio (FCR) were significantly improved in broiler chickens challenged with ethanol and fed with WP (p<.05). Intestinal morphology, humoral responses and heterophil to lymphocyte ratio (H/L) were not affected by WP sources. Cellular immunity responses were significantly lower in control group and challenged birds fed with WP compared with other groups after 48hr of phytohemagglutinin-P (PHA-P) injection. Ethanol challenge decreased liver antioxidant enzyme activities and increased levels of malondialdehyde (MDA) and alanine aminotransferase (ALT) activities. Dietary inclusion of WP and WPC increased levels of liver antioxidant enzymes and decreased MDA and ALT activities. It can be recommended to use WP for improving the growth performance and liver antioxidant enzymes in broiler chickens challenged with ethanol.

Evaluation and Exploration of Potentially Bioactive Peptides in Casein Hydrolysates against Liver Oxidative Damage in STZ/HFD-Induced Diabetic Rats.

Hyperglycemia-induced oxidative stress can cause liver damage in diabetes, and protein hydrolysates with antidiabetic and antioxidant properties are emerging as a potential therapy. In this study, protective effects of casein hydrolysates against live oxidative damage in streptozotocin/high-fat-induced diabetic rats were studied and potentially bioactive peptides were explored by an integrated approach of differential peptide and in silico analysis. Results showed that different casein hydrolysates significantly alleviated liver oxidative damage (p < 0.05) via different mechanisms. Particularly, casein hydrolyzed by a papain-flavourzyme combination (P-FCH) treatment significantly improved liver antioxidant enzyme activities by enhancing nuclear factor erythroid 2-related factor 2 (Nrf2) transcription (p < 0.05). Furthermore, 18 peptides were screened as potential bioactive peptides by analyzing differential peptides among different hydrolysates combined with in silico prediction. Among them, the dipeptide WM might directly inhibit the Kelch-like ECH-associated protein 1 (Keap1)-Nrf2 interaction as potential Nrf2 activators. These results suggested that P-FCH might be an alternative way to treat liver damage in diabetes.

Antioxidant activity and protective effects of the Angelica sinensis-hydroxypropyl-β-cyclodextrin complex on CCl4-induced hepatic failure in mice

Angelica sinensis (Oliv.) Diels (AS) is one of the most popular traditional medicines in China. The components of AS extracts have antioxidant activities and protects against hepatic injury, but minimal solubility in water. The use of 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) to complex the ethanolic extract of AS has been reported to increase the aqueous solubility of AS components. The aim of this study was to investigate the protective effects of the AS-HP-β-CD complex on CCl4-induced hepatic failure in mice and evaluate the antioxidant properties of this complex. The results showed that the antioxidant activity of the AS-HP-β-CD complex was increased compared with that of the AS extract in a dose-dependent manner. In the CCl4-treated mouse model, the AS-HP-β-CD complex more effectively reduced the increases in serum aspartate aminotransferase, serum alanine transferase, and hepatic malondialdehyde concentrations than the AS extract. Similarly, positive effects were also observed in histopathological specimens and in liver antioxidant enzyme activities. Therefore, the results suggested that complexing AS extract with HP-β-CD improved the hepatoprotective effects of AS.

Influence of dietary sodium alginate and Pediococcus acidilactici on liver antioxidant status, intestinal lysozyme gene expression, histomorphology, microbiota, and digestive enzymes activity, in Asian sea bass (Lates calcarifer) juveniles

A 42-day study was conducted to determine the effect of incorporating dietary low molecular weight sodium alginate (LMWSA), extracted from the brown algae, Undaria pinnatifida and Macrocystis pyritera, and Pediococcus acidilactici MA 18/5 M (PA), Lallemand Animal Nutrition S.A., Blagnac, France, on growth performance, antioxidant defense activity, intestinal lysozyme gene (LYZ) expression, histo-morphology, microbiota, and digestive enzymes activity of Asian sea bass (Lates calcarifer) juveniles. Six experimental diets were formulated including: Diet (1) a basal diet (Control), Diet (2) 5 g LMWSA kg−1 diet, Diet (3) 10 g LMWSA kg−1 diet, Diet (4) 0.9 × 107 CFU PA g−1 diet, Diet (5) 5 g LMWSA kg−1 diet + 0.9 × 107 CFU PA g−1 diet, and Diet (6) 10 g LMWSA kg−1 diet + 0.9 × 107 CFU PA g−1 diet were fed to Asian sea bass, L. calcarifer (12.0 ± 0.2 g). The results showed that fish fed PA alone (Diet 4) and the combination of both supplements (Diet 5) had the greatest weight gain. Fish fed Diet 6 and those fed Diet 1 (Control) had the highest and lowest villus height, apparent villus surface and crypt depth, respectively. Fish fed diets administered with PA (Diet 4) or synbiotics (Diets 5 and 6) showed higher total viable and lactic acid bacteria counts than all the other groups. The evaluated digestive enzymes activities including total protease, trypsin, lipase, and α-amylase remarkably increased by administration of LMWSA or its combination with PA. Moreover, liver antioxidant enzymes activities including superoxide dismutase, catalase, and Glutathione S-transferase pronouncedly enhanced following the administration of LMWSA or its combination with PA. Supplementing diet with blends of 10 g kg−1 of LMWSA and PA (Diet 6) more pronouncedly enhanced c-type and g-types LYZ expression in comparison with those fed 5 g kg−1 of LMWSA and PA (Diet 5). Based on the results obtained, it can be claimed incorporating diet with LMWSA and PA separately or in symbiotic form had promising results as functional feed additives in juvenile Asian sea bass L. calcarifer.

Influence of Dietary Astaxanthin on the Hepatic Oxidative Stress Response Caused by Episodic Hyperoxia in Rainbow Trout.

A 13-week feeding trial was carried out with juvenile rainbow trout to test two diets: a control diet without astaxanthin (AX) supplementation (CTRL diet), and a diet supplemented with 100 mg/kg of synthetic AX (ASTA diet). During the last week of the feeding trial, fish were exposed to episodic hyperoxia challenge for 8 consecutive hours per day. Episodic hyperoxia induced physiological stress responses characterized by a significant increase in plasma cortisol and hepatic glycogen and a decrease in plasma glucose levels. The decrease of plasma glucose and the increase of hepatic glycogen content due to episodic hyperoxia were emphasized with the ASTA diet. Hyperoxia led to an increase in thiobarbituric acid-reactive substances in the muscle, diminished by dietary AX supplementation in both liver and muscle. Muscle and liver AX were increased and decreased respectively after 7-day episodic hyperoxia, leading to an increase in flesh redness. This augment of muscle AX could not be attributed to AX mobilization, since plasma AX was not affected by hyperoxia. Moreover, hyperoxia decreased most of antioxidant enzyme activities in liver, whereas dietary AX supplementation specifically increased glutathione reductase activity. A higher mRNA level of hepatic glutathione reductase, thioredoxin reductase, and glutamate-cysteine ligase in trout fed the ASTA diet suggests the role of AX in glutathione and thioredoxin recycling and in de novo glutathione synthesis. Indeed, dietary AX supplementation improved the ratio between reduced and oxidized glutathione (GSH/GSSG) in liver. In addition, the ASTA diet up-regulated glucokinase and glucose-6-phosphate dehydrogenase mRNA level in the liver, signaling that dietary AX supplementation may also stimulate the oxidative phase of the pentose phosphate pathway that produces NADPH, which provides reducing power that counteracts oxidative stress. The present results provide a broader understanding of the mechanisms by which dietary AX is involved in the reduction of oxidative status.

Replacement of fishmeal with processed canola meal in diets for juvenile Nile tilapia (Oreochromis niloticus): Growth performance, mucosal innate immunity, hepatic oxidative status, liver and intestine histology

The present study was carried out to evaluate the effect of processed canola meal (PCM) as fishmeal (FM) substitute in juvenile Nile tilapia diet. Firstly, canola meal (CM) was dephytinized using 2000 IU/kg phytase and subjected to methanolic ammonia solution (MAS). Finally, five isonitrogenous and isoenergetic diets were formulated by inclusion of 0 (control), 12.5, 25, 37.5 and 50% PCM at the expense of dietary FM. Each experimental diet was fed to three randomly allotted groups of 17 juvenile Nile tilapia with an average body weight of 3.5 ± 0.1 g for 36 days. Fish were feed three times a day until apparent satiation. Results showed that there were no statistically significant differences regarding SGR, final body weight and WG between control group and PCM2 (i.e., diet with 25% PCM inclusion level) (p > .05); however receiving diets with higher PCM content (>25%) resulted in significantly decreased growth indices (p < .05). Meanwhile, FCR, FI and apparent digestibility coefficient of protein (ADCprotein) did not differ among experimental groups (p > .05). Digestive enzyme activities, mucosal innate immunity, liver antioxidant enzyme activities and liver tissue malondialdehyde content (MDA) were not significantly affected by dietary inclusion of PCM (p > .05). However, relative gene expression of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were significantly increased by dietary PCM content increment (p < .05). In line with growth performance, histological observations revealed that those fish received higher levels of dietary PCM content (i.e. 37.5 and 50%) showed intensive intestinal and hepatic mononuclear immune cell infiltration, lamina propria expansion and intestinal villus detachment and shortening (p < .05). In conclusion, despite containing lower glucosinolate, phytic acid, phenolic compounds and tannins well within the recommended thresholds for aquatic animals nutrition, diets containing PCM beyond 25% negatively affected the growth performance and intestine and liver tissue histoarchitecture of juvenile Nile tilapia. However, further complementary studies are needed regarding the effects observed on gut histology and expression of antioxidant enzyme genes.