Resveratrol attenuated oxidative stress and inflammatory and mitochondrial dysfunction induced by acute ammonia exposure in gibel carp (Carassius gibelio)

Remission of copper-induced liver injury through the PXR/NF-kB signaling pathway: The effects of dietary curcumin supplementation in largemouth bass (Micropterus salmoides)

The pregnane X receptor (PXR)/nuclear factor-kB (NF-kB) signaling pathway plays a critical role in regulating toxin-induced inflammation and apoptosis in mammals. Whether dietary curcumin (CUR) can prevent copper (Cu)-induced liver injury via this signaling pathway remains to be established in aquatic animals. Juvenile largemouth bass (Micropterus salmoides) were exposed to dietary Cu and CUR treatments for 8 weeks. The results showed that chronic Cu exposure induced oxidative stress, causing liver function damage and liver injury. Cu exposure stimulated inflammation by regulating nf-kb and pro-inflammatory genes such as tnfα and il-1β and promoted apoptotic signals in the liver by modulating bcl2 and casp3 mRNA levels. In addition, Pearson correlation analysis verified that inflammatory and apoptotic responses were important indicators of Cu-induced liver injury. CUR attenuated stress responses by enhancing the antioxidant system. Importantly, CUR significantly stimulated PXR mRNA and protein levels in the Cu + CUR group and suppressed NF-κB activation to inhibit the inflammatory and apoptotic signaling cascade. These results suggest that CUR may be an effective activator of PXR in teleost fishes, exerting cytoprotective effects on Cu-induced liver injury via a PXR-mediated NF-κB repression mechanism. In conclusion, this study is the first to demonstrate that CUR may act as a potent PXR ligand that exerts hepatoprotective effects against Cu-induced liver injury. The findings shed light on the specific regulatory role of the PXR/NF-κB signaling pathway in liver pathogenesis and its potential as a therapeutic target in teleost fishes.

Exploring the novel benefits of leucine: Protecting nitrite-induced liver damage in sub-adult grass carp (Ctenopharyngodon idella) through regulating mitochondria quality control

Leucine is an essential amino acid for fish. The ability of leucine to resist stress in fish has not been reported. Nitrite is a common pollutant in the aquatic environment. Therefore, we investigated the effects of dietary leucine on growth performance and nitrite-induced liver damage, mitochondrial dysfunction, autophagy, and apoptosis for sub-adult grass carp. A total of 450 grass carp (615.91 ± 1.15 g) were selected and randomly placed into 18 net cages. The leucine contents of the six diets were 2.91, 5.90, 8.92, 11.91, 14.93, and 17.92 g/kg, respectively. After a 9-week feeding trial, the nitrite exposure experiment was set up for 96 h. These results indicated that dietary leucine significantly promoted FW, WG, PWG, and SGR of sub-adult grass carp (P < 0.05). Appropriate levels of dietary leucine (11.91-17.92 g/kg) decreased the activities of serum parameters (glucose, cortisol, and methemoglobin contents, glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, and lactate dehydrogenase), the contents of reactive oxygen species (ROS), nitric oxide (NO) and peroxynitrite (ONOO-). In addition, appropriate levels of dietary leucine (11.91-17.92 g/kg) increased the mRNA levels of mitochondrial biogenesis genes (PGC-1α, Nrf1/2, TFAM), fusion-related genes (Opa1, Mfn1/2) (P < 0.05), and decreased the mRNA levels of caspase 3, caspase 8, caspase 9, fission-related gene (Drp1), mitophagy-related genes (Pink1, Parkin) and autophagy-related genes (Beclin1, Ulk1, Atg5, Atg7, Atg12) (P < 0.05). Appropriate levels of dietary leucine (8.92-17.92 g/kg) also increased the protein levels of AMP-activated protein kinase (AMPK), prostacyclin (p62) and decreased the protein levels of protein light chain 3 (LC3), E3 ubiquitin ligase (Parkin), and Cytochrome c (Cytc). Appropriate levels of leucine (8.92-17.92 g/kg) could promote growth performance and alleviate nitrite-induced mitochondrial dysfunction, autophagy, apoptosis for sub-adult grass carp. Based on quadratic regression analysis of PWG and serum GPT activity, dietary leucine requirements of sub-adult grass carp were recommended to be 12.47 g/kg diet and 12.55 g/kg diet, respectively.

New insights into resveratrol attenuates hepatotoxicity in emamectin benzoate-exposed grass carp (Ctenopharyngodon idella) via NO system/NF-κB signaling pathway

Emamectin benzoate (EMB) is extensively used as a crop protection agent. Overuse of EMB poses a serious threat to the quality of water and non-target organisms in the environment. Resveratrol (RES) is a natural phytoalexin with the function of anti-oxidation and anti-inflammation. Nonetheless, it is unclear whether EMB affects the expression of cytokines and induces autophagy, apoptosis, and necroptosis of hepatocytes (L8824 cell) in grass carp (Ctenopharyngodon idella), and whether RES has an attenuate function in this process. Therefore, we established the L8824 cells model of EMB exposure and treated it with RES. The results showed that compared with the control (CON) group, EMB exposure significantly increased the nitric oxide (NO) content, inducible nitric oxide synthase (iNOS) activity, and the expression of iNOS and phosphorylated nuclear factor kappa B (p-NF-κB) (P < 0.05). In addition, compared with the CON group, the results of flow cytometry and dansylcadaverine (MDC) staining showed a significant increase in apoptosis and autophagy in the EMB-exposed group (P < 0.05) with the activation of the B-cell lymphoma-2 (Bcl-2)/Bcl-2 associated X (Bax)/cysteine-aspartic acid protease 3 (Caspase-3)/cysteine-aspartic acid protease 9 (Caspase-9) pathway and microtubule-associated protein light chain 3 (LC3)/sequestosome 1 (p62)/Beclin1 pathway. EMB exposure significantly increased the mRNA and protein expression of receptor-interacting protein 1 (RIPK1)/receptor-interacting protein 3 (RIPK3)/mixed the lineage kinase domain-like (MLKL) pathway (P < 0.05). Moreover, EMB exposure significantly increased the expression of genes related to immunity (immunoglobulin G (IgG), immunoglobulin M (IgM), and immunoglobulin D (IgD), and antimicrobial peptide-related genes expression including β-defensin and hepcidin) (P < 0.05). The addition of RES significantly diminished autophagy, apoptosis, necroptosis, and immunity-related gene expression by inhibiting iNOS activity, NO content, and the protein expression of iNOS and p-NF-κB. In conclusion, RES attenuated autophagy, apoptosis, and necroptosis in EMB-exposed L8824 cells via suppression of the NO system/NF-κB signaling pathway.

Resveratrol Alleviates Zearalenone-Induced Intestinal Dysfunction in Mice through the NF-κB/Nrf2/HO-1 Signalling Pathway

Zearalenone (ZEA), a mycotoxin widely present in crops and food, poses a major threat to animal and human health. The consumption of ZEA-contaminated food or feed causes intestinal damage. Therefore, exploring how to mitigate the intestinal damage caused by its ZEA is becoming increasingly important. Resveratrol (RSV), a polyphenol compound, mainly exists in Vitis vinifera, Polygonum cuspidatum, Arachis hypogaea, and other plants. It has potent anti-inflammatory and antioxidant activity. The primary objective of this study was to assess the defensive effects of RSV and its molecular mechanism on the intestinal mucosal injury induced by ZEA exposure in mice. The results showed that RSV pretreatment significantly reduced serum DAO and that D-lactate levels altered intestinal morphology and markedly restored TJ protein levels, intestinal goblet cell number, and MUC-2 gene expression after ZEA challenge. In addition, RSV significantly reversed serum pro-inflammatory factor levels and abnormal changes in intestinal MDA, CAT, and T-SOD. Additional research demonstrated that RSV decreased inflammation by blocking the translocation of nuclear factor-kappaB (NF-κB) p65 and decreased oxidative stress by activating the nuclear factor E2-related factor 2 (Nrf2) pathway and its associated antioxidant genes, including NQO1, γ-GCS, and GSH-PX. In summary, RSV supplementation attenuates intestinal oxidative stress, inflammation, and intestinal barrier dysfunction induced by ZEA exposure by mediating the NF-κB and Nrf2/HO-1 pathways.

Progress in Understanding Oxidative Stress, Aging, and Aging-Related Diseases

Under normal physiological conditions, reactive oxygen species (ROS) are produced through redox reactions as byproducts of respiratory and metabolic activities. However, due to various endogenous and exogenous factors, the body may produce excessive ROS, which leads to oxidative stress (OS). Numerous studies have shown that OS causes a variety of pathological changes in cells, including mitochondrial dysfunction, DNA damage, telomere shortening, lipid peroxidation, and protein oxidative modification, all of which can trigger apoptosis and senescence. OS also induces a variety of aging-related diseases, such as retinal disease, neurodegenerative disease, osteoarthritis, cardiovascular diseases, cancer, ovarian disease, and prostate disease. In this review, we aim to introduce the multiple internal and external triggers that mediate ROS levels in rodents and humans as well as the relationship between OS, aging, and aging-related diseases. Finally, we present a statistical analysis of effective antioxidant measures currently being developed and applied in the field of aging research.

Resveratrol impacts on aquatic animals: a review

Aquaculture has intensified tremendously with the increasing demand for protein sources as the global population grows. However, this industry is plagued with major challenges such as poor growth performance, the lack of a proper environment, and immune system impairment, thus creating stress for the aquaculture species and risking disease outbreaks. Currently, prophylactics such as antibiotics, vaccines, prebiotics, probiotics, and phytobiotics are utilized to minimize the negative impacts of high-density farming. One of the promising prophylactic agents incorporated in fish feed is resveratrol, a commercial phytophenol derived via the methanol extraction method. Recent studies have revealed many beneficial effects of resveratrol in aquatic animals. Therefore, this review discusses and summarizes the roles of resveratrol in improving growth performance, flesh quality, immune system, antioxidant capacity, disease resistance, stress mitigation, and potential combination with other prophylactic agents for aquatic animals.

IR-based device to acquire real-time online heart ECG signals of fish (Cyprinus carpio) to evaluate the water quality

Water quality monitoring is a challenging task due to continuous pollution. The rapid development of engineering technologies has paved the way for the development of efficient and convenient computer-based online continuous water-quality assessment techniques. Techniques based on biological-responses are gaining attention, worldwide. Different biosensors have been developed in recent years to monitor real-time biological responses to evaluate water-quality. The survival and function of various organs of the organism depends on the cardiac system. Alterations in the cardiac system could signify the occurrence/initiation of stress in the organism. We developed a real-time online cardiac function assessment system-OCFAS to acquire fish ECG-signals. We obtained P-wave, R-wave, T-wave, PR-intervals, QT-intervals and QRS-complex continuously, which did not affect the normal activities of carp. We exposed Cyprinus carpio to different concentrations (National Environmental Quality Standards) of ammonia for 48 h. Our OCFAS has precisely acquired the required ECG-signals. A real-time dataset reveals sensitivity to ammonia in carp ECG-indexes. Compared with the control group the P-wave, R-wave and T-wave were weaker in ammonia-treated groups. In contrast, the PR-intervals, QT-intervals and QRS-complex were prolonged in the ammonia-treatment groups. The self-organizing map signifies that the PR-intervals, the QRS-complex and the QT-intervals are consistent with environmental stress. Linear regression analysis also quantitatively signifies that the PR interval has the highest R2 value and the lowest SSE-value, followed by the QRS complex and the QT interval. A concentration-related effect was observed in the ammonia treated groups. The integrated biomarker response (IBRv2) index was used to determine the overall stress of ammonia on carp heart ECG-indexes. IBRv2 also supports the real-time response of carp to ammonia stress. Ammonia levels in the aquaculture and water environment require special attention to avoid its adverse effects on the health of aquatic biota. Our study emphasizes the importance of online real-time fish ECG for water-quality assessment.

Modified rougan decoction attenuates hepatocyte apoptosis through ameliorating mitochondrial dysfunction by upregulated SIRT1/PGC-1α signaling pathway

The modified rougan decoction (MRGD) compound formula has been proven a certain ability to relieve lipopolysaccharide-enrofloxacin (LPS-ENR)-induced liver oxidant injury in chickens. Recent advances have shown that mitochondrial dysfunction affects the development of many diseases, leading to increased interest in exploring its effects. Using LPS-ENR-injured in vivo and in vitro to further evaluate the effects of MRGD on mitochondrial structure and function, and emphasized further investigation of its molecular mechanism. After LPS-ENR treatment, the levels of inflammation and apoptosis markers were increased, along with higher mitochondrial injury. Results showed that MRGD reduced inflammatory factors expression and inhibited the nuclear translocation of NF-κB P65, reducing the inflammatory response in vivo and in vitro. Additionally, MRGD pretreatment inhibited mitochondrial dysfunction, mitochondrial oxidative stress, and mitochondrial pathway apoptosis by maintaining mitochondrial structure and function. Moreover, treatment with the inhibitor EX527 showed that MRGD promoted mitochondrial biogenesis ability through the SIRT1/PGC-1α pathway and interfered with mitochondrial dynamics, and activate Nrf2. In summary, MRGD played a key role in promoting mitochondrial function and thus alleviating hepatocyte apoptosis in vivo and in vitro at least in part.

Apoptotic Changes, Oxidative Stress and Immunomodulatory Effects in the Liver of Japanese Seabass (Lateolabrax japonicus) Induced by Ammonia-Nitrogen Stress during Keep-Live Transport

This study investigated the effects of NH₃-N on antioxidant responses, histoarchitecture, and immunity of Japanese seabass (Lateolabrax japonicus) during keep-live transport. The findings suggest that NH₃-N stress transport alters the transcription of P53, Caspase 9, Bcl2, Caspase 3 and Bax genes, demonstrating that NH₃-N stress can trigger the apoptotic pathway of P53-Bax-Bcl2 and Caspase and induce apoptosis. NH₃-N stress transport also evoked transcriptional upregulation of inflammatory cytokines (tumor necrosis factor α (TNF-α), Toll-like receptor 3 (TLR-3), nuclear factor kappa β (NF-κB), interleukin 6 (IL-6) and interleukin 1β (IL-1β)) and increased complement C3, C4, lysozyme (LZM) and immunoglobulin (IgM) levels, activating the innate immunological system during keep-live transport. In addition, NH₃-N stress transport altered changes in the levels of superoxide dismutase (SOD), catalase (CAT), glutathione-related enzymes, and heat shock proteins 70 and 90 in the liver, indicating that the antioxidant system and Hsp protected the cells from NH₃-N-induced oxidative stress. When excess ROS were not removed, they caused the body to respond with immunological and inflammatory responses, as well as apoptosis and tissue damage. This helps towards understanding the effect of NH₃-N levels on sea bass during keep-live transport.

Dietary Chlorella vulgaris effectively alleviates oxidative stress, immunosuppression, and enhances the resistance to Streptococcus agalactiae infection in cadmium-intoxicated Nile tilapia fingerlings

Aquatic pollutants, including cadmium (Cd), cause oxidative stress on aquatic animals. The use of probiotics, including microalgae as a feed additive to alleviate the toxic impacts of heavy metals, is a much more interesting point. Hence, the current study investigated the oxidative stress and immunosuppression in Nile tilapia (Oreochromis niloticus) fingerlings caused by Cd toxicity as well as the preventive function of dietary Chlorella vulgaris against Cd toxicity. Accordingly, fish were fed on 0.0 (control), 5, and 15 g/kg diet of Chlorella up to satiation thrice a day, along with being exposed to 0.0 or 2.5 mg Cd/L for 60 days. Following the experimental procedure, fish from each group were intraperitoneally injected with Streptococcus agalactiae, and their survivability was observed for further ten days. Chlorella-supplemented diets meaningfully (P < 0.05) boosted the antioxidative capability of fish, which was evidenced by higher activities of hepatic superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione-S-transferase (GST) as well as higher levels of reduced glutathione (GSH) along with significant reductions in hepatic malondialdehyde levels. Moreover, the innate immunity indices [phagocytic activity (PA), respiratory burst activity (RBA), and alternative complement activity (ACH50)] were significantly higher in Chlorella-fed fish, particularly in the group of 15 g/kg diet. Additionally, serum of Chlorella-fed fish showed potent bactericidal activities against S. agalactiae, particularly at the treatment of a 15 g/kg diet. Feeding Chlorella diets to Nile tilapia fingerlings upregulated SOD, CAT, and GPx genes expression alongside the down-regulation of IL-1β, IL-8, IL-10, TNF-α, and HSP70 genes expression. Conversely, Cd toxicity caused oxidative stress and suppressed the fish's innate immunity with upregulation of the expression of IL-1β, IL-8, IL-10, TNF-α, and HSP70 genes. Feeding Cd-exposed fish on Chlorella-containing diets attenuated these adverse effects. The current research revealed that supplementing feeds with the treatment of 15 g/kg diet of C. vulgaris supports the antioxidant-immune responses and alleviates the Cd toxicity effects on Nile tilapia fingerlings.

Effects of Curcumin on Oxidative Stress and Ferroptosis in Acute Ammonia Stress-Induced Liver Injury in Gibel Carp (Carassius gibelio)

This study investigated the potential role of curcumin (CUR) in preventing oxidative stress and ferroptosis induced by ammonia exposure in gibel carp. Experimental fish (initial weight: 11.22 ± 0.10 g, n = 150) were fed diets supplemented with or without 0.5% CUR for 56 days, followed by a 24 h ammonia (32.5 mg/L) exposure. Liver damages (aspartate aminotransferase (AST), alanine aminotransferase (ALT), adenosine deaminase (ADA), and alkaline phosphatase (ALP)) and oxidative stress enzyme activities (reactive oxygen species (ROS), malondialdehyde (MDA); and the content of antioxidant capacity (T-AOC), superoxide dismutase (SOD), and glutathione peroxidase (GPx)) were induced by ammonia stress. The antioxidant capacity was decreased, as indicated by inhibited gene expression of nuclear factor erythroid 2-related factor 2 (nrf2), heme oxygenase-1 (ho-1), catalase (cat), and sod. Ferroptosis was induced by ammonia stress, as suggested by upregulated mRNA levels of nuclear receptor coactivator 4 (ncoa4), transferrin receptor 1 (tfr1), and iron-responsive element-binding protein 2 (ireb2), and downregulated expression of glutathione peroxidase 4 (gpx4), ferroportin (fpn), and ferritin heavy chain 1 (fth1). In addition, both mRNA and protein levels of ferroptosis markers acyl-CoA synthetase long-chain family member 4 (ACSL4) and prostaglandin-endoperoxide synthase 2 (PTGS2) were upregulated, while cystine/glutamate antiporter (SLC7A11) was downregulated. However, liver injury and ferroptosis in fish induced by ammonia could be attenuated by CUR. Collectively, these findings demonstrate that CUR ameliorates oxidative stress and attenuates ammonia stress-induced ferroptosis. This study provides a new perspective on potential preventive strategies against ammonia stress in gibel carp by dietary CUR.

Resveratrol alleviates lipopolysaccharide-induced liver injury by inducing SIRT1/P62-mediated mitophagy in gibel carp (Carassius gibelio)

Introduction

Resveratrol (RES) is a polyphenol organic compound with antioxidant and anti-inflammatory properties. This study aimed to determine whether and how RES can alleviate liver injury in lipopolysaccharide (LPS)-induced gibel carp.

Methods

Gibel carp were fed a diet with or without RES and were cultured for 8 weeks, followed by LPS injection.

Results and discussion

The results suggested that RES attenuated the resulting oxidative stress and inflammation by activating the Nrf2/Keap1 pathway and inhibiting the NF-κB pathway, as confirmed by changes in oxidative stress, inflammation-related gene expression, and antioxidant enzyme activity. Furthermore, RES cleared damaged mitochondria and enhanced mitochondrial biogenesis to mitigate reactive oxygen species (ROS) accumulation by upregulating the SIRT1/PGC-1α and PINK1/Parkin pathways and reducing p62 expression. Overall, RES alleviated LPS-induced oxidative stress and inflammation in gibel carp through mitochondria-related mechanisms.