Search Results (54)

Sitosterol (Sito) is a phytosterol with bioactive properties, including reducing atherosclerosis risk and anti-inflammatory and antitumoral effects. However, it can be oxidized by reactive oxygen species such as ozone (O₃), producing oxyphytosterols with harmful effects such as cytotoxicity, oxidative stress, and proatherogenicity. Ozone, a strong oxidant and common pollutant, can alter plant steroid compounds, raising concerns about dietary oxyphytosterol intake. Studies identify β-Secosterol (βSec) as the primary ozone-derived oxyphytosterol from Sito, exhibiting cytotoxic effects on HepG2 human liver tumor cells. This study investigated βSec’s biological effects on two rat liver cell lines: BRL-3A (immortalized) and HTC (tumoral), examining cell death, cell cycle progression, morphology, and cytoskeleton organization. While Sito influenced cell metabolic activity without affecting cell survival or morphology, βSec demonstrated significant cytotoxicity in both cell lines. It induced G0/G1 cell cycle arrest and disrupted cytoskeleton organization, with different implications: BRL-3A cells showed persistent cytoskeletal changes potentially linked to tumor induction, while HTC cells displayed chemoresistance, restoring cytoskeletal integrity and enhancing metastatic potential. These findings reveal βSec’s complex, context-dependent effects, suggesting it may promote tumor-like behavior in non-tumoral cells and resistance mechanisms in cancer cells, contributing to understanding oxyphytosterols’ implications for physiological and pathological conditions. Full article

Background/Objectives: Abnormal bile acid (BA) pool may play an important role in inducing liver damage in sepsis. Farnesoid X receptor (FXR) is a main negative feedback regulator of BA metabolism. This study aims to explore the protective effect and mechanism of the FXR agonist obeticholic acid (OCA) on liver dysfunction when sepsis occurs. Methods: A rat model of sepsis was induced by cecal ligation and puncture (CLP) for 24 h. Systematic inflammation, tissue injury, hepatic FXR, and BA transporter expression were investigated in the CLP rats and sham-operated control rats with and without OCA pre-treatment (10 mg/kg, gavage) at 2 h before operation. Liquid chromatography–tandem mass spectrometry (LC-MS/MS) assay was performed to access BA composition in the rats’ serum and livers. The injury and inflammatory effects of the elevated unconjugated BAs found in the CLP rats was further verified in a hepatic cell line BRL-3A in vitro. Results: Hepatic FXR was repressed in CLP rats, whereas OCA upregulated liver FXR and hepatic BA transporter expression, reduced total serum BA concentration, ameliorated the elevation of serum levels of IL-1β and IL-6, and improved liver and ileal tissue injuries. OCA administration reduced the elevated unconjugated BAs in both serum and liver, and effectively inhibited increases in cholic acid (CA), deoxycholic acid (DCA), and 7-ketoDCA concentrations in CLP rat livers. These BA fractions promoted the release of aspartate aminotransferase (AST) from BRL-3A cells and increased IL-6, CXCL2, and monocyte chemoattractant protein-1 (MCP-1) expression in the cells, along with enhanced transcription factor nuclear factor-κB activation. Conclusions: Liver inflammation and dysfunction during sepsis is attributable to significant changes in bile acid composition in the blood and liver. FXR activation reduces systemic inflammation and liver dysfunction by regulating bile acid homeostasis, especially inflammatory unconjugated bile acid components. Full article

Excessive iron accumulation poses a significant threat to liver health, primarily through oxidative stress and autophagy dysregulation. α-Lipoic acid (ALA), a natural antioxidant with hepatoprotective properties, may alleviate iron-induced liver damage, but its underlying mechanisms are not fully understood. This study utilized male Sprague Dawley rats and BRL-3A cells to explore the protective effects of ALA against iron overload in vivo and in vitro, respectively. ALA treatment significantly reduced hepatic iron accumulation, improved liver morphology, and alleviated iron-induced ultrastructural damage in rats. ALA also improved liver function markers in plasma, including alkaline phosphatase (ALP), gamma-glutamyltransferase (GGT), total bilirubin (TBIL), and the AST/ALT ratio. Furthermore, ALA mitigated iron-induced oxidative stress by lowering hepatic reactive oxygen species (ROS) and malondialdehyde (MDA), while increasing the antioxidant enzyme activities of glutathione peroxidase (GSH-Px) and catalase (CAT). In BRL-3A cells, ALA improved cell viability, decreased intracellular ROS, and reduced iron levels. Proteomics analysis indicates that NAD(P)H: quinone oxidoreductase 1 (NQO1) may play a critical role in the protective effects of ALA against iron overload-induced hepatic damage in rats. Mechanistically, ALA upregulated NQO1 expression while downregulating autophagy-related proteins, including light chain 3B (LC3B), lysosomal-associated membrane protein 1 (LAMP1), and cathepsin D (CTSD). Inhibition or knockdown of NQO1 abolished ALA’s protective effects, confirming its role in reducing oxidative stress and excessive autophagy. These findings highlight the potential of ALA as a therapeutic agent for managing hepatic iron toxicity through iron chelation and activation of NQO1. Full article

Background/Objectives: Constant inflammation can be a detrimental response in bone regeneration. To regulate of the inflammatory response and synchronically promote rapid tissue regeneration is a vital clinical challenge. The urinary bladder matrix (UBM) and small intestinal submucosa (SIS) composite are commonly used extracellular matrix (ECM) materials. We designed a novel drug-loaded membrane by integrating the biological matrix (BM) composed of UBM and SIS composites with Resolvin D1 (RvD1), an endogenous pro-resolving lipid mediator, using the lyophilization process. This membrane is referred to as BRL, an acronym for BM-RvD1-Lyophilization. Methods: In this study, the physicochemical properties of the membranes were characterized. Fluorescence staining and the CCK8 assay kit were utilized to assess biocompatibility. To evaluate the inflammatory resolution properties and osteogenic ability of osteoblasts, real-time quantitative PCR and ELISA were conducted. Results: BRL exhibited a more pronounced three-dimensional pore structure, demonstrating excellent physicochemical properties and enabling the slow release of RvD1. This approach improved the viability of MG63 osteoblast-like cells, reduced LPS-induced inflammation, and upregulated osteogenesis-related genes significantly. Conclusions: By integrating inflammation control capabilities into tissue regeneration materials, BRL effectively regulates the tissue regeneration microenvironment, thereby enhancing regeneration efficiency and positioning itself as an exceptional candidate for future tissue regeneration membranes. Full article

Background: Liver regeneration is a critical measure of liver health and plays an essential role in inhibiting the progression of fibrotic lesions and preventing liver failure after hepatocellular carcinoma surgery. However, there are no approved drugs to address this clinical challenge. Methods: The effects of TUDCA on liver regeneration and fibrosis were studied using BRL-3A cells, a partial hepatectomy (PH) rat liver regeneration model, and a carbon tetrachloride (CCl₄)-induced liver fibrosis model. GATA3-knockdown BRL-3A cells were employed to assess the role of GATA3 in TUDCA-induced proliferation. Results: TUDCA promoted the proliferation of BRL-3A cells and enhanced liver regeneration in PH rats while ameliorating liver fibrosis in CCl₄-treated rats. Additionally, the knockdown of GATA3 eliminated the proliferative effect of TUDCA on BRL-3A cells. Conclusions: TUDCA promotes liver regeneration and alleviates liver fibrosis by activating GATA3. Full article

Background/Objectives: Chronic alcohol overconsumption triggers alcohol liver injury, and therapeutic strategies targeting alcohol-triggered oxidative stress and hepatic inflammatory responses represent potential approaches to ameliorating alcohol-related hepatotoxicity. This study aimed to determine the hepatoprotective activity of finger citron essential oil (FCEO) in alcoholic liver disease (ALD)-afflicted rats and explore its underlying mechanisms. In order to identify the effective components, we compared the effects of FCEO and D-limonene. Methods: The regulatory effects of FCEO on metabolic enzymes were systematically evaluated through in vitro experiments. In vivo studies were conducted to investigate and compare the hepatoprotective effects of FCEO and D-limonene. Staining methods, assay kits, and Western Blot were used to determine the roles of FCEO and D-limonene in the ALD rats. Results: We found that FCEO downregulated phase I metabolic enzymes and upregulated phase II metabolic enzymes in Buffalo Rat Liver-3A (BRL-3A) cells. FCEO and/or D-limonene intervention reduced transaminase levels in ALD rats and effectively alleviated inflammatory cell infiltration and lipid droplet accumulation in their liver tissue. Additionally, FCEO and D-limonene played a regulatory role in oxidative stress and inflammation-related pathways such as the MAPK/Nrf2 and NF-κB/AMPK pathways. FCEO was superior to D-limonene as an antioxidant in alleviating alcoholic liver injury. Conclusions: This study revealed the alleviative effects and mechanisms of FCEO on alcoholic liver injury, demonstrating better efficacy compared to its monomer, thus providing a strategy for the development and utilization of finger citron resources. Full article

The beta-3 adrenergic receptor (β3-AR), whose expression is modulated by oxygen levels, was found to play a key role in organ maturation, and its agonism was reported to mitigate hyperoxia-induced large bowel damage by preventing organ hypoplasia, preserving epithelial integrity, vascularization, and the neurochemical coding in the colonic myenteric plexus. This study explored the effects of β3-AR agonism in preventing hyperoxia-related alterations on the ileal enteric nervous system (ENS). Sprague–Dawley rat pups were reared under normoxia or hyperoxia (85%) during the first two weeks after birth and treated or not with the β3-AR agonist BRL37344 at 1, 3, or 6 mg/kg. Hyperoxia caused an imbalance of inhibitory nitrergic and excitatory cholinergic neurons in both the myenteric and submucosal plexuses and decreased the amounts of neurons in the submucosal plexus and that of S100β⁺ and GFAP⁺ glial cells in the myenteric plexus. Administration of 3 mg/kg BRL37344 preserved the neuronal chemical coding and partially prevented the loss of myenteric GFAP⁺ glial cells, while it did not counteract submucosal neuronal loss. Our findings indicate the potential of β3-AR agonism as a new therapeutic strategy for hyperoxia-induced ileal ENS alterations. Full article

(1) Background: Cystic echinococcosis (CE) is an Echinococcus granulosus-induced worldwide parasitic zoonosis and is a recognized public health and socio-economic concern. The liver is the major target organ for CE’s infective form protoscolex (PSCs), which causes serious liver damage and endangers the host’s life. Reports show that PSC infection causes liver cell Fe²⁺ metabolism disorder and abnormal deposition of Fe²⁺ in liver cells and results in liver cell death. However, whether PSC-induced liver cell death is associated with ferroptosis remains to be clarified. (2) Methods: Using both an in vivo rat model and an in vitro co-culture of PSCs and the cell system, we studied the histopathological progress of PSCs infection and the cytopathogenesis of PSC-induced cell death in the liver. Hepatic-injury-related ferroptosis signaling pathways were identified by proteomics analysis at various stages of PSCs infection, and physiological and the biochemical indexes and expression of pathway proteins related to hepatic ferroptosis were studied. Ferrostatin-1, a ferroptosis inhibitor, was employed for in vivo interference with early protoscolices infection in rats, and the effects of the inhibition of hepatocyte ferroptosis on hepatocyte injury and the generation of fibrotic cysts were investigated. Additionally, PSCs were exposed to in vitro co-culture with BRL, a rat hepatocyte line, to clarify the direct influences of PSCs on BRL ferroptosis. (3) Results: The results of our in vivo studies revealed that PSCs infection induced Fe²⁺ enrichment in liver cells surrounding the PSCs cysts, cellular oxidation, and liver tissue damage along with the prolongation of PSCs parasitism. The results of our in vitro studies verified the ability of PSCs to directly induce ferroptosis, the formation of fibrotic cysts, and alteration of the iron metabolism of liver cells. The analysis of KEGG signaling pathways revealed that ferroptosis- and ROS-related pathways were significantly induced with PSCs infection. Using Ferrostatin-1 effectively blocked ferroptosis, reversed Fe²⁺ content, reduced liver cell oxidation, and reduced PSC-induced fibrosis cysts. (4) Conclusions: Our study reveals the histopathological progress of PSC infection and the cytopathogenesis of PSC-induced ferroptosis. Ferrostatin-1 effectively blocked PSCs infection and PSC-induced cell death in vivo and in vitro. Accordingly, the inhibition of PSC-induced hepatocyte ferroptosis may be an effective method in the control of Echinococcus granulosus infection and should be seriously considered in clinical studies. Full article

Iron is a trace element that is indispensable for the growth and development of animals. Excessive iron supplementation may lead to iron overload and elevated reactive oxygen species (ROS) production in animals, causing cellular damage. Nevertheless, the precise mechanism by which iron overload causes cell injury remains to be fully elucidated. In this study, 16 male SD rats aged 6 to 7 weeks were randomly assigned to either a control group (CON) or an iron overload group (IO). Rats in the iron overload group received 150 mg/kg iron dextran injections every three days for a duration of four weeks. The results indicated that iron treatment with iron dextran significantly increased the scores of steatosis (p < 0.05) and inflammation (p < 0.05) in the NAS score. The integrated transcriptomic and proteomic analysis suggests that HO-1 and Lnc286.2 are potentially significant in iron overload-induced liver injury in rats. In vitro experiments utilizing ferric ammonium citrate (FAC) were conducted to establish an iron overload model in rat liver-derived BRL-3A cells. The result found that FAC treatment can significantly increase the BRL-3A cell’s Fe²⁺ content (p < 0.05), ROS (p < 0.01), lipid ROS (p < 0.01) levels, and the expression of the HO-1 gene and protein (p < 0.01), aligning with proteomic and transcriptomic findings. HO-1 inhibition can significantly decrease BRL-3A cell vitality (p < 0.01) and promote ROS (p < 0.05) and lipid ROS (p < 0.01), thus aggravating FAC-induced BRL-3A cell iron overload damage. Using the agonist of HO-1 agonist cobalt protoporphyrin (CoPP) to induce HO-1 overexpression can significantly alleviate the decrease in FAC-induced BRL-3A cell viability (p < 0.01), ROS (p < 0.01), and lipid ROS (p < 0.01). In addition, siLnc286.2 treatment can increase HO-1 expression, alleviate the decline of FAC-induced BRL-3A cell activity, and increase lipid ROS (p < 0.05) content. In conclusion, the findings of this study suggest that by suppressing the expression of Lnc286.2, we can enhance the expression of HO-1, which in turn alleviates lipid peroxidation in cells and increases their antioxidant capacity, thereby exerting a protective effect against liver cell injury induced by iron overload. Full article

Carnitine-acylcarnitine translocase (CACT) is a nuclear-encoded mitochondrial carrier that catalyzes the transfer of long-chain fatty acids across the inner mitochondrial membrane for β-oxidation. In this study, we conducted a structural and functional characterization of the CACT promoter to investigate the molecular mechanism underlying the transcriptional regulation of the CACT gene by n-3 PUFA, EPA and DHA. In hepatic BRL3A cells, EPA and DHA stimulate CACT mRNA and protein expression. Deletion promoter analysis using a luciferase reporter gene assay identified a n-3 PUFA response region extending from −202 to −29 bp. This region did not contain a response element for PPARα, a well-known PUFA-responsive nuclear receptor. Instead, bioinformatic analysis revealed two highly conserved GABP responsive elements within this region. Overexpression of GABPα and GABPβ subunits, but not PPARα, increased CACT promoter activity, more remarkably upon treatment with EPA and DHA. ChIP assays showed that n3-PUFA enhanced the binding of GABPα to the −202/−29 bp sequence. Furthermore, both EPA and DHA induced nuclear accumulation of GABPα. In conclusion, our findings indicate that the upregulation of CACT by n3-PUFA in hepatic cells is independent from PPARα and could be mediated by GABP activation. Full article

Organogenesis occurs in the uterus under low oxygen levels (4%). Preterm birth exposes immature newborns to a hyperoxic environment, which can induce a massive production of reactive oxygen species and potentially affect organ development, leading to diseases such as necrotizing enterocolitis. The β3-adrenoreceptor (β3-AR) has an oxygen-dependent regulatory mechanism, and its activation exerts an antioxidant effect. To test the hypothesis that β3-AR could protect postnatal ileal development from the negative impact of high oxygen levels, Sprague–Dawley rat pups were raised under normoxia (21%) or hyperoxia (85%) for the first 2 weeks after birth and treated or not with BRL37344, a selective β3-AR agonist, at 1, 3, or 6 mg/kg. Hyperoxia alters ileal mucosal morphology, leading to increased cell lipid oxidation byproducts, reduced presence of β3-AR-positive resident cells, decreased junctional protein expression, disrupted brush border, mucin over-production, and impaired vascularization. Treatment with 3 mg/kg of BRL37344 prevented these alterations, although not completely, while the lower 1 mg/kg dose was ineffective, and the higher 6 mg/kg dose was toxic. Our findings indicate the potential of β3-AR agonism as a new therapeutic approach to counteract the hyperoxia-induced ileal alterations and, more generally, the disorders of prematurity related to supra-physiologic oxygen exposure. Full article

Asexual development is the main propagation and transmission mode of Beauveria bassiana and the basis of its pathogenicity. The regulation mechanism of conidiation and the key gene resources for utilization are key links to improving the conidia yield and quality of Beauveria bassiana. Their clarification may promote the industrialization of fungal pesticides. Here, we compared the regulation of morphology, resistance to external stress, virulence, and nutrient utilization capacity between the upstream developmental regulatory gene fluG and the key genes brlA, abaA, and wetA in the central growth and development pathway. The results showed that the ΔbrlA and ΔabaA mutants completely lost the capacity to conidiate and that the ΔwetA mutant had seriously reduced conidiation capacity. Although the deletion of fluG did not reduce the conidiation ability as much as deletions of brlA, abaA, and wetA, it significantly reduced the fungal response to external stress, virulence, and nutrient utilization, while the deletion of the three other genes had little effect. Via transcriptome analysis and screening the yeast nuclear system library, we found that the differentially expressed genes in the ΔfluG mutants were concentrated in the signaling pathways of ABC transporters, propionate metabolism, tryptophan metabolism, DNA replication, mismatch repair, and fatty acid metabolism. FluG directly acted on 40 proteins that were involved in various signaling pathways such as metabolism, oxidative stress, and cell homeostasis. The analysis indicated that the regulatory function of fluG was mainly involved in DNA replication, cell homeostasis, fungal growth and metabolism, and the response to external stress. Our results revealed the biological function of fluG in asexual development and the responses to several environmental stresses as well as its influence on the asexual development regulatory network in B. bassiana. Full article

Various antioxidants are tested to improve the viability and development of cryopreserved oocytes, due to their known positive health effects. The aim of this study was to find whether astaxanthin (AX), a xanthophyll carotenoid, could mitigate deteriorations that occurred during the vitrification/warming process in bovine oocytes. Astaxanthin (2.5 µM) was added to the maturation medium during the post-warm recovery period of vitrified oocytes for 3 h. Afterward, the oocytes were fertilized in vitro using frozen bull semen and presumptive zygotes were cultured in the B2 Menezo medium in a co-culture with BRL-1 cells at 38.5 °C and 5% CO₂ until the blastocyst stage. AX addition significantly reduced ROS formation, lipid peroxidation, and lysosomal activity, while increasing mitochondrial activity in vitrified oocytes. Although the effect of AX on embryo development was not observed, it stimulated cell proliferation in the blastocysts derived from vitrified oocytes and improved their quality by upregulation or downregulation of some genes related to apoptosis (BCL2, CAS9), oxidative stress (GPX4, CDX2), and development (GJB5) compared to the vitrified group without AX. Therefore, the antioxidant properties of astaxanthin even during short exposure to bovine vitrified/warmed oocytes resulted in improved blastocyst quality comparable to those from fresh oocytes. Full article

Lead and cadmium are foodborne contaminants that threaten human and animal health. It is well known that lead and cadmium produce hepatotoxicity; however, defense mechanisms against the co-toxic effects of lead and cadmium remain unknown. We investigated the mechanism of autophagy (defense mechanism) against the co-induced toxicity of lead and cadmium in rat hepatocytes (BRL-3A cells). Cultured rat liver BRL-3A cell lines were co-cultured with 10, 20, 40 μM lead and 2.5, 5, 10 μM cadmium alone and in co-culture for 12 h and exposed to 5 mM 3-Methyladenine (3-MA), 10 μM rapamycin (Rapa), and 50 nM Beclin1 siRNA to induce cellular autophagy. Our results show that treatment of BRL-3A cells with lead and cadmium significantly decreased the cell viability, increased intracellular reactive oxygen species levels, decreased mitochondrial membrane potential levels, and induced apoptosis, which are factors leading to liver injury, and cell damage was exacerbated by co-exposure to lead–cadmium. In addition, the results showed that lead and cadmium co-treatment induced autophagy. We further observed that the suppression of autophagy with 3-MA or Beclin1 siRNA promoted lead–cadmium-induced apoptosis, whereas enhancement of autophagy with Rapa suppressed lead–cadmium-induced apoptosis. These results demonstrated that co-treatment with lead and cadmium induces apoptosis in BRL-3A cells. Interestingly, the activation of autophagy provides cells with a self-protective mechanism against induced apoptosis. This study provides insights into the role of autophagy in lead–cadmium-induced apoptosis, which may be beneficial for the treatment of lead–cadmium-induced liver injury. Full article

Aspergillus fumigatus is the leading cause of aspergillosis, associated with high mortality rates, particularly in immunocompromised individuals. In search of novel genetic targets against aspergillosis, we studied the WOPR transcription factor OsaA. The deletion of the osaA gene resulted in colony growth reduction. Conidiation is also influenced by osaA; both osaA deletion and overexpression resulted in a decrease in spore production. Wild-type expression levels of osaA are necessary for the expression of the conidiation regulatory genes brlA, abaA, and wetA. In addition, osaA is necessary for normal cell wall integrity. Furthermore, the deletion of osaA resulted in a reduction in the ability of A. fumigatus to adhere to surfaces, decreased thermotolerance, as well as increased sensitivity to oxidative stress. Metabolomics analysis indicated that osaA deletion or overexpression led to alterations in the production of multiple secondary metabolites, including gliotoxin. This was accompanied by changes in the expression of genes in the corresponding secondary metabolite gene clusters. These effects could be, at least in part, due to the observed reduction in the expression levels of the veA and laeA global regulators when the osaA locus was altered. Importantly, our study shows that osaA is indispensable for virulence in both neutropenic and corticosteroid-immunosuppressed mouse models. Full article