Thioredoxin domain-containing protein 5 (TXNDC5) plays a role in diseases related to oxidative stress, energy metabolism, and cellular inflammation. This protein has also been associated with diabetes and insulin folding. To gain insight into these relationships, glucose metabolism was characterized using Txndc5-deficient mice. The absence of TXNDC5 lowered glycemia, which was correlated with higher non-esterified fatty acid (NEFA) levels following an overnight fast on a chow diet in males. Several tolerance tests (pyruvate, glucose, and insulin) revealed no impairment in gluconeogenesis, but rather, higher insulin sensitivity. In vitro assays using an engineered hepatic cell line corroborated the results of increased glucose uptake. When a high-fat, high-sucrose diet was administered to induce a prediabetic state, the absence of TXNDC5 reproduced the lower glycemia and higher NEFA levels observed in mice consuming the chow diet. However, higher levels of plasma insulin were observed in Txndc5-deficient mice. The insulin receptor was increased in the hepatic plasma membranes. Increased hepatic gene expression of G6pc, Irs2, and Igfbp1 was also observed in the absence of TXNDC5. These results indicate that TXNDC5 plays a role in the hepatic sex-differential handling of glucose and lipids, and in retaining the insulin receptor on the plasma membrane.

Lactarius deliciosus is a widely distributed edible mushroom valued as a functional food due to its rich content of nutrients, phenolic compounds, and flavonoids, which contribute to its strong antioxidant and antimicrobial properties. The present study aimed to optimize a green microwave-assisted extraction method for maximal recovery of bioactive phenolic compounds from Lactarius deliciosus extract (LDE) and to evaluate its antioxidant, antiproliferative, antimetastatic, and anti-inflammatory effects on human colon carcinoma (Caco-2) cells. The study demonstrated that solvent polarity and composition critically influence the recovery of antioxidant biomolecules, identifying water and NaDES 1 (glycerol/glycine/water) as the most efficient and sustainable solvents for microwave-assisted extraction at 225 °C. The LDE showed high levels of phenolic compounds-particularly 4-hydroxybenzoic and vanillic acids-indicating potent antioxidant potential and possible anticancer efficacy. The results revealed that the LDE significantly reduced colony formation and cell adhesion in a dose-dependent manner, leading to nearly complete inhibition of clonogenic survival at the IC50 concentration and a marked increase in cell death among non-adherent colon cancer cells. In addition, LDE inhibited the proliferation of Caco-2 cells by inducing G0/G1 cell cycle arrest and apoptosis, associated with altered mitochondrial potential and increased caspase-3 activity. The LDE modified the redox balance of the cell by decreasing the ROS levels and exerts anti-inflammatory effects through significant downregulation of NOS2 expression, without adversely affecting the intestinal barrier. The study concludes that LDE bioactive compounds show strong promise as anticancer and functional ingredients, demonstrating antioxidant, antiproliferative, antimetastatic, and anti-inflammatory effects.

Cytochrome P450, family 7, subfamily b, polypeptide 1 (CYP7B1) is a widely expressed enzyme involved in the hydroxylation of sterols. Generated by transposon technology in zygotes, male rats lacking Cyp7b1 expression in homozygosis showed an absence of Cyp7b1 mRNA expression in the liver, small intestine, adipose tissue, and muscle. Elevated levels of 25-hydroxycholesterol were found in the liver of mutant rats. After overnight fasting, plasma triglyceride (TG) levels were increased in the homozygous rats. In agreement with this, increased hepatic secretion of very-low-density lipoprotein-TG (VLDL) in fasting rats treated with tyloxapol and decreased low-density receptor protein (LDLr) on the hepatocyte plasma membranes were observed. The decrease in LDLr was not due to decreased mRNA expression but to increased expressions of its proteases (Psck9 and Mylip). RNA sequencing identified Fasn, Igfbp2, and Pcsk9 as targets of the Cyp7b1 absence. However, the hepatic protein contents of IGFBP2 were increased in Cyp7b1-deficient rats, accompanied by a normal glucose tolerance test. HepG2 cells lacking CYP7B1 showed increased expressions of FASN and IGFBP2. These results suggest a role of CYP7B1 in the control of hepatic IGFBP2 and VLDL-TG secretion as a prediabetes sign exerted through 25-hydroxycholesterol and transcriptional or translational mechanisms depending on the species.

To test the effects of extra virgin olive oil (EVOO) enriched in specific bioactive compounds (EVOO HBC) on atherosclerosis and fatty liver, three isocaloric Western diets differing in the type of fat (palm, EVOO, or EVOO HBC) were fed to Apoe-deficient mice for 12 weeks. Plasma lipids, lipoprotein characterization, circulating CD36-expressing monocytes, and M2 peritoneal macrophages were quantified. Hepatic squalene and cross-sectional and en face atherosclerotic lesions were analyzed. Compared to the palm group, plasma triglyceride and glucose levels increased, while APOA1, paraoxonase 1 activity, and lipoprotein oxidation decreased in mice fed both EVOO groups. The latter stored liver squalene according to the amount consumed. En face and cross-sectional atherosclerotic lesions were lower in the EVOO groups. CD36 expression in circulating monocytes was lower and M2 peritoneal macrophages were higher in the EVOO groups. In males, there was a reduced presence of CD68-expressing cells in atherosclerotic plaques, while in females, there was a reduction in en face lesions that negatively correlated with high-density lipoprotein (HDL)-phospholipid efflux. The recruitment of macrophages into atherosclerotic plaques and the improvement of HDL efflux may be sex-dependent and attributable to the high content of squalene and a specific oleuropein aglycone.

Background: Staphylococcus aureus is one of the most prevalent bacteria in skin and soft tissue infections (SSTIs). Multidrug-resistant strain emergence, particularly methicillin-resistant S. aureus (MRSA), highlights the need for alternative treatments. Objectives: This study investigates the antimicrobial properties of olive leaf extract (OLE) and describes an epidemiological profiling of patients with SSTI who may benefit from it. Methods: OLE was tested in two reference strains, methicillin-susceptible S. aureus (MSSA) ATCC 29213 and MRSA ATCC 700699, and in 126 clinical isolates from patients with SSTIs according to Clinical Laboratory Standards Institute guidelines. Results: The minimum bactericidal concentration (MBC) ranged from 3.12% to 6.25% w/v for MSSA and 1.56% to 3.12% for MRSA. The lethal curve showed a reduction of 6 log10CFU/mL after two hours of incubation. Most of the 126 clinical samples (103 MSSA and 23 MRSA) came from skin lesions, surgical wounds, and ulcers. Over 90% of MSSA strains were resistant to less than five antibiotics, while 82% of MRSA strains were resistant to more than six. Penicillins demonstrated the lowest susceptibility rate (19.8%), whereas linezolid, daptomycin, pristinamycin, trimethoprim–sulfamethoxazole, teicoplanin, vancomycin, and OLE exhibited 100% susceptibility. No growth was observed for all clinical strains with OLE at ≥6.25% w/v. Conclusions: The findings suggest that OLE could become a promising alternative treatment for skin infections, particularly in the context of increasing antibiotic resistance.

Background: There are conflicting studies reporting both an increase and a decrease in vitamin B12 (VB12) levels in non-alcoholic fatty liver disease (NAFLD). In this study, we aimed to dissect the effects of steatosis and fibrosis on VB12. Methods: This is a cross-sectional study including all patients with a vibration-controlled transient elastography (VCTE) performed at the Hospital Miguel Servet (Zaragoza, Spain) between 2019 and 2022 for a chronic liver disease and having a recent blood test for VB12 levels. Liver fibrosis was assessed by VCTE and hepatic steatosis by ultrasonography and/or through controlled attenuation parameter (CAP). Results: 1195 patients (NAFLD n = 441, other chronic liver disease n = 754) were included. Median age was 57 years, 53% female. Patients with NAFLD had lower levels of VB12 compared to the rest of chronic liver diseases (289 vs. 313 pg/mL, p < 0.001). A significant negative correlation was observed between VB12 levels and hepatic steatosis measured by CAP (r = −0.13, p < 0.001). A significant positive correlation was observed between VB12 levels and liver stiffness in patients with NAFLD in both sexes (men r = 0.31, p < 0.001 and women r = 0.15, p = 0.016). A significant association between VB12 levels and liver fibrosis in cirrhosis stage was observed in patients with NAFLD (OR 1.06, 95% CI, 1.025–1.098, p = 0.001). Conclusion: VB12 levels were lower with greater hepatic steatosis. In NAFLD, VB12 levels were lower compared to other chronic liver diseases but their levels increased with higher liver stiffness and in cirrhosis stage.

Non-alcoholic fatty liver disease (NAFLD) is a progressive liver disease characterized by the build-up of fat in the liver of individuals in the absence of alcohol consumption. This condition has become a burden in modern societies aggravated by the lack of appropriate predictive biomarkers (other than liver biopsy). To better understand this disease and to find appropriate biomarkers, a new technology has emerged in the last two decades with the ability to explore the unmapped role of lipids in this disease: lipidomics. This technology, based on the combination of chromatography and mass spectrometry, has been extensively used to explore the lipid metabolism of NAFLD. In this review, we aim to summarize the knowledge gained through lipidomics assays exploring tissues, plasma, and lipoproteins from individuals with NAFLD. Our goal is to identify common features and active pathways that could facilitate the finding of a reliable biomarker from this field. The most frequent observation was a variable decrease (1–9%) in polyunsaturated fatty acids in phospholipids and non-esterified fatty acids in NAFLD patients, both in plasma and liver. Additionally, a reduction in phosphatidylcholines is a common feature in the liver. Due to the scarcity of studies, further research is needed to properly detect lipoprotein, plasma, and tissue lipid signatures of NAFLD etiologies, and NAFLD subtypes, and to define the relevance of this technology in disease management strategies in the push toward personalized medicine.

Boletus edulis (BE) is a mushroom well known for its taste, nutritional value, and medicinal properties. The objective of this work was to study the biological effects of BE extracts on human colon carcinoma cells (Caco-2), evaluating parameters related to oxidative stress and inflammation. In this study, a hydroethanolic extract of BE was obtained by ohmic heating green technology. The obtained BE extracts are mainly composed of sugars (mainly trehalose), phenolic compounds (taxifolin, rutin, and ellagic acid), and minerals (K, P, Mg, Na, Ca, Zn, Se, etc.). The results showed that BE extracts were able to reduce cancer cell proliferation by the induction of cell cycle arrest at the G0/G1 stage, as well as cell death by autophagy and apoptosis, the alteration of mitochondrial membrane potential, and caspase-3 activation. The extracts modified the redox balance of the cell by increasing the ROS levels associated with a decrease in the thioredoxin reductase activity. Similarly, BE extracts attenuated Caco-2 inflammation by reducing both iNOS and COX-2 mRNA expression and COX-2 protein expression. In addition, BE extracts protected the intestine from the oxidative stress induced by H2O2. Therefore, this study provides information on the potential use of BE bioactive compounds as anticancer therapeutic agents and as functional ingredients to prevent oxidative stress in the intestinal barrier.

Hepatic thioredoxin domain-containing 5 (TXNDC5) is a member of the protein disulfide isomerase family found associated with anti-steatotic properties of squalene and located in the endoplasmic reticulum and in lipid droplets. Considering that the latter are involved in hepatic squalene accumulation, the present research was aimed to investigate the role of TXNDC5 on hepatic squalene management in mice and in the AML12 hepatic cell line. Wild-type and TXNDC5-deficient (KO) mice were fed Western diets with or without 1% squalene supplementation for 6 weeks. In males, but not in females, absence of TXNDC5 blocked hepatic, but not duodenal, squalene accumulation. Hepatic lipid droplets were isolated and characterized using label-free LC-MS/MS analysis. TXNDC5 accumulated in this subcellular compartment of mice receiving squalene and was absent in TXNDC5-KO male mice. The latter mice were unable to store squalene in lipid droplets. CALR and APMAP were some of the proteins that responded to the squalene administration in all studied conditions. CALR and APMAP were positively associated with lipid droplets in the presence of squalene and they were decreased by the absence of TXNDC5. The increased squalene content was reproduced in vitro using AML12 cells incubated with squalene-loaded nanoparticles and this effect was not observed in an engineered cell line lacking TXNDC5. The phenomenon was also present when incubated in the presence of a squalene epoxidase inhibitor, suggesting a mechanism of squalene exocytosis involving CALR and APMAP. In conclusion, squalene accumulation in hepatic lipid droplets is sex-dependent on TXNDC5 that blocks its secretion.

The pathogenesis of non-alcoholic fatty liver disease (NAFLD) is influenced by a number of variables, including endoplasmic reticulum stress (ER). Thioredoxin domain-containing 5 (TXNDC5) is a member of the protein disulfide isomerase family and acts as an endoplasmic reticulum (ER) chaperone. Nevertheless, the function of TXNDC5 in hepatocytes under ER stress remains largely uncharacterized. In order to identify the role of TXNDC5 in hepatic wild-type (WT) and TXNDC5-deficient (KO) AML12 cell lines, tunicamycin, palmitic acid, and thapsigargin were employed as stressors. Cell viability, mRNA, protein levels, and mRNA splicing were then assayed. The protein expression results of prominent ER stress markers indicated that the ERN1 and EIF2AK3 proteins were downregulated, while the HSPA5 protein was upregulated. Furthermore, the ATF6 protein demonstrated no significant alterations in the absence of TXNDC5 at the protein level. The knockout of TXNDC5 has been demonstrated to increase cellular ROS production and its activity is required to maintain normal mitochondrial function during tunicamycin-induced ER stress. Tunicamycin has been observed to disrupt the protein levels of HSPA5, ERN1, and EIF2AK3 in TXNDC5-deficient cells. However, palmitic acid has been observed to disrupt the protein levels of ATF6, HSPA5, and EIF2AK3. In conclusion, TXNDC5 can selectively activate distinct ER stress pathways via HSPA5, contingent on the origin of ER stress. Conversely, the absence of TXNDC5 can disrupt the EIF2AK3 cascade.

Squalene, a triterpene found in extra virgin olive oil, has therapeutic properties in diseases related to oxidative stress, such as cancer. However, its hydrophobic nature and susceptibility to oxidation limit its bioavailability outside of olive oil. To expand its applications, alternative delivery methods are necessary. The objective of the present study was to examine the impact of squalene encapsulated in PLGA (poly(lactic-co-glycolic) acid) nanoparticles (PLGA + Sq) on the proliferation of human colon carcinoma Caco-2 cells, as well as its underlying mechanism of action. The findings demonstrated that PLGA + Sq exert no influence on differentiated cells; however, it is capable of reducing the proliferation of undifferentiated Caco-2 cells through apoptosis and cell cycle arrest in the G1 phase. This effect was initiated by the release of cytochrome c into the cytoplasm and the subsequent activation of caspase-3. Furthermore, squalene exhibited pro-oxidant activity, as evidenced by an increase in intracellular ROS (reactive oxygen species) levels. The results of the squalene effect on genes associated with cell death, inflammation, and the cell cycle indicate that its antiproliferative effect may be post-transcriptional. In conclusion, PLGA + Sq demonstrate an antiproliferative effect on Caco-2 cells through apoptosis by altering redox balance, suggesting squalene’s potential as a functional food ingredient for colorectal cancer prevention.

This review focuses on the thioredoxin domain containing 5 (TXNDC5), also known as endoplasmic reticulum protein 46 (ERp46), a member of the protein disulfide isomerase (PDI) family with a dual role in multiple diseases. TXNDC5 is highly expressed in endothelial cells, fibroblasts, pancreatic β-cells, liver cells, and hypoxic tissues, such as cancer endothelial cells and atherosclerotic plaques. TXNDC5 plays a crucial role in regulating cell proliferation, apoptosis, migration, and antioxidative stress. Its potential significance in cancer warrants further investigation, given the altered and highly adaptable metabolism of tumor cells. It has been reported that both high and low levels of TXNDC5 expression are associated with multiple diseases, such as arthritis, cancer, diabetes, brain diseases, and infections, as well as worse prognoses. TXNDC5 has been attributed to both oncogenic and tumor-suppressive features. It has been concluded that in cancer, TXNDC5 acts as a foe and responds to metabolic and cellular stress signals to promote the survival of tumor cells against apoptosis. Conversely, in normal cells, TXNDC5 acts as a friend to safeguard cells against oxidative and endoplasmic reticulum stress. Therefore, TXNDC5 could serve as a viable biomarker or even a potential pharmacological target.

The Mediterranean diet is a well-known dietary pattern that has gained considerable popularity worldwide for its ability to prevent the progression of nonalcoholic fatty liver disease. This is largely attributed to the use of virgin olive oil as the primary source of fat, which contains a substantial amount of squalene, a natural antioxidant. In order to enhance the delivery of squalene and amplify its effects due to its highly hydrophobic nature, herein, squalene has been incorporated into chitosan nanoparticles. The characterization of the resulting nanoparticles was conducted via scanning electron microscopy, dynamic light scattering, ζ potential, Fourier transform infrared spectroscopy, and gas chromatography-mass spectrometry. Reactive oxygen species (ROS) generation and cell viability assays were conducted in oxidative and endoplasmic reticulum (ER) stress in AML12 and a TXNDC5-deficient AML12 cell line, which was generated by CRISPR/Cas9 technology. The results demonstrated that squalene was successfully encapsulated in chitosan nanoparticles and exhibited rapid and efficient cellular uptake at a 150 μM squalene concentration within 48 h. In conclusion, the encapsulation of squalene in chitosan nanoparticles, compared to the poly(d,l-lactide-co-glycolic acid) and ethanol drug carriers, significantly enhanced its cellular uptake. This allows the administration of higher doses, which improve hepatocyte viability and reduce ROS levels, effectively compensating for the adverse effects of TXNDC5 deficiency under the context of hepatocyte stress protection.

Olive oil is the main source of lipid energy in the Mediterranean diet and there is strong evidence of its health benefits. The effect of extra virgin olive oil (EVOO) in the form of a preparation of spreadable virgin olive oil (S-VO) on the progression of atheroma plaques was investigated in Apoe-deficient mice, a model of accelerated atherosclerosis. Methods: Two isocaloric Western purified diets containing 20% fat, either as S-VO or as dairy butter, were used to feed 28 males and 16 females of two-month-old Apoe-deficient mice for 12 weeks. S-VO was prepared by blending more than 75% virgin olive oil with other vegetal natural fat to obtain a solid fat. Plasma total cholesterol, triglycerides and HDL cholesterol were measured. Hepatic lipid droplets were analyzed. Areas of atherosclerotic aortic lesions were quantified in cross-sectional images of the proximal aorta and en face analysis of the whole aorta. Results: Total plasma cholesterol was increased in mice on the butter-supplemented diet in both female and male mice compared to S-VO, and the ratio of TC/HDL-cholesterol was significantly lower in S-VO than in the butter diet, although only in males, and no differences in plasma triglycerides were observed. No significant differences in hepatic lipid droplets were observed between diets in either sex. Aortic lesion areas were significantly higher in mice consuming the butter versus the S-VO diet in both sexes. Conclusion: Extra virgin olive oil prepared in spreadable form maintained the delay in atheroma plaque progression compared to butter.

A NASH stage was obtained in crossbred pigs. Hepatic [PC(33:0), PC(33:1) and PC(34:0)] or plasma [FA 16:0, FA 18:0 and LPC(17:1)] species were sensitive parameters to detect subtle changes in development and regression of nonalcoholic steatohepatitis (NASH). These findings may delineate the liquid biopsy to detect subtle changes in progression or in treatments. Furthermore, phospholipid changes according to the insult-inducing NASH may play an important role in accepting or rejecting fatty livers in transplantation.

This Special Issue is devoted to nutrition genomics, which is the characterization of the whole genome response to nutrients, in an effort to gather all the available pertinent information and to establish the foundation for a future encyclopedia of genomic responses driven by diets or nutrients [...].

Introduction The lower rates of cardiovascular disease in Southern Europe could be partially explained by the low prevalence of lipid-rich atheroma plaques. Consumption of certain foods affects the progression and severity of atherosclerosis. We investigated whether the isocaloric inclusion of walnuts within an atherogenic diet prevents phenotypes predicting unstable atheroma plaque in a mouse model of accelerated atherosclerosis. Methods Apolipoprotein E-deficient male mice (10-week-old) were randomized to receive a control diet (9.6% of energy as fat, n = 14), a palm oil-based high-fat diet (43% of energy as fat, n = 15), or an isocaloric diet in which part of palm oil was replaced by walnuts in a dose equivalent to 30 g/day in humans (n = 14). All diets contained 0.2% cholesterol. Results After 15 weeks of intervention, there were no differences in size and extension in aortic atherosclerosis among groups. Compared to control diet, palm oil-diet induced features predicting unstable atheroma plaque (higher lipid content, necrosis, and calcification), and more advanced lesions (Stary score). Walnut inclusion attenuated these features. Palm oil-based diet also boosted inflammatory aortic storm (increased expression of chemokines, cytokines, inflammasome components, and M1 macrophage phenotype markers) and promoted defective efferocytosis. Such response was not observed in the walnut group. The walnut group’s differential activation of nuclear factor kappa B (NF-κB; downregulated) and Nrf2 (upregulated) in the atherosclerotic lesion could explain these findings. Conclusion The isocaloric inclusion of walnuts in an unhealthy high-fat diet promotes traits predicting stable advanced atheroma plaque in mid-life mice. This contributes novel evidence for the benefits of walnuts, even in an unhealthy dietary environment.

Objectives: The type and amount of dietary protein have become a topic of renewed interest, considering their involvement in several diseases. However, little attention has been devoted to the effect of avian proteins despite their wide human consumption. In a previous study, we saw that compared with soybean protein, the consumption of avian proteins, depending on sex, resulted in similar or lower atherosclerosis with a higher paraoxonase 1 activity, an antioxidant enzyme carried by high-density lipoproteins (HDL). This suggests that under these conditions, the HDL lipoproteins may undergo important changes. The aim of this research was to study the influence of soybean, chicken, and turkey proteins on the characteristics of HDL.Methods: Male and female Apoedeficient mice were fed purified Western diets based on the AIN-93 diet, differing only in the protein source, for 12 wk. After this period, blood and liver samples were taken for analysis of HDL composition and hepatic expression of genes related to HDL metabolism (Abca], Lcat, Pltp, Pon], and Scarb]). Depending on sex, these genes define a different network of interactions. Females consuming the turkey protein-containing diet showed decreased atherosclerotic foci, which can be due to larger very-low-density lipoproteins (VLDLs) calculated by molar ratio triacylglycerols/VLDL cholesterol and higher expression of Lcat. In contrast, in males, a higher ratio of paraoxonase1 to apolipoprotein A1 decreased the oxidative status of the different lipoproteins, and augmented Abca] expression was observed. Conclusions: The source of protein has an effect on the development of atherosclerosis depending on sex by modifying HDL characteristics and the expression of genes involved in their properties.(c) 2023 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Squalene is a key minor component of virgin olive oil, the main source of fat in the Mediterranean diet, and had shown to improve the liver metabolism in rabbits and mice. The present research was carried out to find out whether this effect was conserved in a porcine model of hepatic steatohepatitis and to search for the lipidomic changes involved. The current study revealed that a 0.5% squalene supplementation to a steatotic diet for a month led to hepatic accumulation of squalene and decreased triglyceride content as well as area of hepatic lipid droplets without influencing cholesterol content or fiber areas. However, ballooning score was increased and associated with the hepatic squalene content. Of forty hepatic transcripts related to lipid metabolism and hepatic steatosis, only citrate synthase and a non-coding RNA showed decreased expressions. The hepatic lipidome, assessed by liquid chromatography-mass spectrometry in a platform able to analyze 467 lipids, revealed that squalene supplementation increased ceramide, Cer(36:2), and phosphatidylcholine (PC[32:0], PC[33:0] and PC[34:0]) species and decreased cardiolipin, CL(69:5), and triglyceride (TG[54:2], TG[55:0] and TG[55:2]) species. Plasma levels of interleukin 12p40 increased in pigs receiving the squalene diet. The latter also modified plasma lipidome by increasing TG(58:12) and decreasing non-esterified fatty acid (FA 14:0, FA 16:1 and FA 18:0) species without changes in total NEFA levels. Together this shows that squalene-induced changes in hepatic and plasma lipidomic profiles, non-coding RNA and anti-inflammatory interleukin are suggestive of an alleviation of the disease despite the increase in the ballooning score.

Non-alcoholic fatty liver disease or steatosis is an accumulation of fat in the liver. Increased amounts of non-esterified fatty acids, calcium deficiency, or insulin resistance may disturb endoplasmic reticulum (ER) homeostasis, which leads to the abnormal accumulation of misfolded proteins, activating the unfolded protein response. The ER is the primary location site for chaperones like thioredoxin domain-containing 5 (TXNDC5). Glutathione participates in cellular oxidative stress, and its interaction with TXNDC5 in the ER may decrease the disulfide bonds of this protein. In addition, glutathione is utilized by glutathione peroxidases to inactivate oxidized lipids. To characterize proteins interacting with TXNDC5, immunoprecipitation and liquid chromatography–mass spectrometry were used. Lipid peroxidation, reduced glutathione, inducible phospholipase A2 (iPLA2) and hepatic transcriptome were assessed in the AML12 and TXNDC5-deficient AML12 cell lines. The results showed that HSPA9 and PRDX6 interact with TXNDC5 in AML12 cells. In addition, TXNDC5 deficiency reduced the protein levels of PRDX6 and HSPA9 in AML12. Moreover, lipid peroxidation, glutathione and iPLA2 activities were significantly decreased in TXNDC5-deficient cells, and to find the cause of the PRDX6 protein reduction, proteasome suppression revealed no considerable effect on it. Finally, hepatic transcripts connected to PRDX6 and HSPA9 indicated an increase in the Dnaja3, Mfn2 and Prdx5 and a decrease in Npm1, Oplah, Gstp3, Gstm6, Gstt1, Serpina1a, Serpina1b, Serpina3m, Hsp90aa1 and Rps14 mRNA levels in AML12 KO cells. In conclusion, the lipid peroxidation system and glutathione mechanism in AML12 cells may be disrupted by the absence of TXNDC5, a novel protein–protein interacting partner of PRDX6 and HSPA9.