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Abstract Lamb meat is highly valued across various cultures and regions due to its unique flavor and nutritional benefits. As the primary component of edible meat, skeletal muscle holds significant economic value and research importance. However, previous studies have largely focused on a limited array of muscle groups, overlooking the differences between various types. Therefore, a comprehensive transcriptomic and meat quality analysis of the skeletal muscles of sheep and goats is essential to improve meat production traits. In this study, we performed RNA sequencing and assessed meat quality in 10 different skeletal muscles from 2-year-old Liangshan Black sheep and Meigu Black goats. We generated 803.16 Gb of high-quality bulk RNA sequencing data with six biological replicates for each muscle. This dataset provides a deeper understanding of the gene expression profiles and meat quality characteristics of different muscle tissues in sheep and goats, laying the foundation for broader comparative research.

BackgroundOsteoporosis (OP), as the prevalent systemic metabolic bone disease worldwide, progresses insidiously and slowly. The clinical discomfort and complications associated with OP impose a significant burden on patients. Therefore, finding more effective treatments for OP remains an urgent challenge.MethodWe first conducted in vitro experiments to determine whether Neoandrographolide (NEO) exhibits cytotoxic or proliferative effects on bone marrow macrophages (BMMs) and to explore the specific timeframe during which NEO exerts its inhibitory action on osteoclast (OC) differentiation. Through Reverse Transcription Polymerase Chain Reaction (RT-PCR) and Western blot analysis, we examined the relative expression levels of genes and proteins associated with OC differentiation like CTSK,c-Fos,MMP9,NFATc1, and verified the underlying mechanisms. Finally, we performed in vivo experiments to further investigate the inflammation.ResultsNEO exhibits no significant cytotoxic effects on BMMs at concentrations less than or equal to 30 μM while exerting inhibitory effects on OC differentiation during its early and middle stages. RT-PCR and Western blot results reveal that NEO suppresses the expression of genes and proteins including CTSK,c-Fos,MMP9,NFATc1. Western blot findings also indicate that NEO inhibits the phosphorylation of ERK, P38, JNK, and P65 but does not reverse the degradation of IκB-α. Additionally, NEO affects the phosphorylation of proteins in the PI3K/AKT, GSK3β, and PPARγ signaling pathways, demonstrating that NEO can inhibit OC formation through multiple pathways and targets. In vivo experiments further validated the in vitro findings by constructing an OP model, showing that NEO can mitigate bone loss induced by OC differentiation.ConclusionNEO has the potential to serve as a therapeutic agent for OP by targeting multiple sites and inhibiting the formation of mature OC through various signaling pathways.

A database of 115 bio-actives from seven subclasses, including information on retention time, parent ion m/z, fragment m/z, and isotopic fit, was established, and an instrumental method for simultaneous analysis of these targets was optimised. An ultrasound-assisted preparation method at 50 °C for 50 min with a 1:60 solid-liquid ratio, water as the solvent was proposed for the screening of unknown components and the antioxidant analysis in saffron. The self-built database and untargeted analysis identified 32 and 103 bio-actives in saffron, respectively. The comparative analysis revealed that the antioxidant capacity of saffron petals was superior to that of stigmas. Correlation and multivariate statistical analyses indicated that terpenoids may be the main active substances in stigmas, while flavonoids and carboxylic acid derivatives play a pivotal role in conferring antioxidant activity to de-stigmatised saffron. The method serves as an ideal tool for mining the functional components of saffron and other agricultural products.

Abstract The major histocompatibility complex class I (MHCI) trafficking signal (MITD) plays a pivotal role in enhancing the efficacy of mRNA vaccines. However, there was a lack of research investigating its efficacy in enhancing immune responses to RNA virus infections. Here, we have developed an innovative strategy for the formulation of mRNA vaccines. This approach involved the integration of MITD into the mRNA sequence encoding the virus antigen. Mechanistically, MITD‐based mRNA vaccines can strengthen immune protection by mimicking the dynamic trafficking properties of MHCI molecule and thus expand the memory specific B and T cells. The model MITD‐based mRNA vaccines encoding binding receptor‐binding domain (RBD) of SARS‐CoV‐2 were indeed found to achieve protective duration, optimal storage stability, broad efficacy, and high safety.

ABSTRACT: Dermal hyperpigmentation stands out among the various skin pigmentation phenotypes in chickens, where most other pigmentation variants affect feather color and patterning predominantly. Despite numerous black chicken breeds worldwide, only a select few exhibit comprehensive black pigmentation, which encompasses the skin, meat, flesh, and bones. The process of skin melanin pigmentation is intricate and develops successively. Historically, research has concentrated primarily on specific developmental points or stages, but fewer studies have examined the entire transcriptome across the timeline of the development of the embryo integument. In our investigation, we undertook the sequencing of chicken embryo skin samples from d 4 to d 13 of incubation. Our results showed that melanoblasts continued to migrate from E4 to the epidermis until E12. Beginning with E6, melanin was synthesized and transferred to epidermal cells and feather follicles in large quantities, and genes such as DCT, TYR, TYRP1, and MITF played a key role in this process, which is significantly different from that of white-skinned chickens. There were 854 differentially expressed genes between E7 and E8. At this stage, melanocytes formed dendritic forms and transferred melanin to keratinocytes, while the dorsal skin became visibly dark. In addition, CDH3, which is a core factor involved in a variety of biological processes, may have an important impact on skin melanin pigmentation. Collectively, our findings unveiled a phased relationship between the canonical pathway and the noncanonical pathway from E4 to E13. These analyses illuminated the gene regulatory mechanism and provided foundational data that pertained to pigmentation in chickens.

Abstract The signal sequence played a crucial role in the efficacy of mRNA vaccines against virus pandemic by influencing antigen translation. However, limited research had been conducted to compare and analyze the specific mechanisms involved. In this study, a novel approach was introduced by substituting the signal sequence of the mRNA antigen to enhance its immune response. Computational simulations demonstrated that various signal peptides differed in their binding capacities with the signal recognition particle (SRP) 54 M subunit, which positively correlated with antigen translation efficiency. Our data revealed that the signal sequences of tPA and IL-6-modified receptor binding domain (RBD) mRNA vaccines sequentially led to higher antigen expression and elicited more robust humoral and cellular immune protection against the SARS-CoV-2 compared to the original signal sequence. By highlighting the importance of the signal sequence, this research provided a foundational and safe approach for ongoing modifications in signal sequence-antigen design, aiming to optimize the efficacy of mRNA vaccines.

Puan Panjiang black-bone chickens are renowned for their distinctive traits, deep black coloration, and high-quality protein content, making them a focus of genetic research due to their unique egg-laying abilities. In this study, 110 Puan Panjiang black-bone chickens were used to investigate the effects of natural and artificial selection influencing egg production. Whole-genome resequencing data from red junglefowl (RJF) and high-egg-production (HEP) and low-egg-production (LEP) groups of Puan Panjiang black-bone chickens revealed significant genetic variants associated with egg production traits. Additionally, transcriptome analysis of 47 samples from ovary stroma, small white follicles (SWFs), small yellow follicles (SYFs), and liver tissues from 6 HEP and 6 LEP groups identified differentially expressed genes. Notably, differences in egg production were linked to small yellow follicles rather than ovary stroma or SWFs. Key candidate genes, including TRIM7, CASR, SPTBN5, GAL1, ZP1, IL4I1, and CCL19, were identified as potential contributors to egg-laying performance. This study underscores the genetic diversity within this breed and provides valuable insights for future breeding programs to enhance egg production, supporting the sustainable development of this local resource.

BackgroundDistal radial artery (DRA) access is an infrequent alternative access for pediatric catheterization. The feasibility of using the DRA for arterial catheterization in children depends on the vessel's size.ObjectivesThis study aims to provide a reference for pediatric catheterization via DRA access by evaluating the diameter of the DRA in the anatomic snuffbox (AS).MethodsWe conducted a retrospective review of clinical and vascular ultrasound data of 412 children (ages 3–12) who were scheduled for arterial blood gas analysis via the DRA due to serious respiratory diseases between June 2023 and October 2023.ResultsThe corrected DRA diameter in the AS was 1.97 ± 0.37 mm overall, with no significant difference between males (1.98 ± 0.38 mm) and females (1.95 ± 0.35 mm) (p = 0.457). The anteroposterior, transverse, and corrected DRA diameters increased significantly with age (p 2.0 mm and >1.5 mm increased significantly with age (p

There are currently approximately 4000 mutations in the SARS-CoV-2 S protein gene and emerging SARS-CoV-2 variants continue to spread rapidly worldwide. Universal vaccines with high efficacy and safety urgently need to be developed to prevent SARS-CoV-2 variants pandemic. Here, we described a novel self-assembling universal mRNA vaccine containing a heterologous receptor-binding domain (HRBD)-based dodecamer (HRBDdodecamer) against SARS-CoV-2 variants, including Alpha (B.1.1.7), Beta (B.1.351), Gamma (B.1.1.28.1), Delta (B.1.617.2) and Omicron (B.1.1.529). HRBD containing four heterologous RBD (Delta, Beta, Gamma, and Wild-type) can form a stable dodecameric conformation under T4 trimerization tag (Flodon, FD). The HRBDdodecamer -encoding mRNA was then encapsulated into the newly-constructed LNPs consisting of a novel ionizable lipid (4N4T). The obtained universal mRNA vaccine (4N4T-HRBDdodecamer) presented higher efficiency in mRNA transfection and expression than the approved ALC-0315 LNPs, initiating potent immune protection against the immune escape of SARS-CoV-2 caused by evolutionary mutation. These findings demonstrated the first evidence that structure-based antigen design and mRNA delivery carrier optimization may facilitate the development of effective universal mRNA vaccines to tackle SARS-CoV-2 variants pandemic.

Bile, a crucial fluid produced continuously by the liver, plays an essential role in digestion within the small intestine. Beyond its primary function in lipid digestion, bile also acts as a pathway for the elimination of various endogenous and exogenous substances. There have been limited studies focusing on interspecies differences. This study offers a comprehensive analysis of bile acid (BA) composition and its correlation with gene expression patterns across six different species, including mammals and poultry, through combining Liquid Chromatography-Mass Spectrometry (LC-MS) and transcriptome sequencing. The BA profiles revealed distinct metabolite clusters: D-glucuronic acid (GLCA) and glycochenodeoxycholic acid (GCDCA) were predominant in mammals, while taurolithocholic acid (TLCA) and T-alpha-MCA were prevalent in poultry, highlighting species-specific BA compositions. Differentially abundant metabolites, particularly GDCA, glycohyodeoxycholic acid (GHDCA) and taurodeoxycholic acid (TDCA) showed significant variations across species, with pigs showing the highest BA content. Transcriptome analysis of the liver and small intestine tissues of 56 cDNA libraries across the six species revealed distinct mRNA expression patterns. These patterns clustered samples into broad categories based on tissue type and phylogenetic relationships. Furthermore, the correlation between gene expression and BA content was examined, identifying the top 20 genes with significant associations. These genes potentially serve as biomarkers for BA regulation.

Acidosis, regardless of hypoxia involvement, is recognized as a chronic and harsh tumor microenvironment (TME) that educates malignant cells to thrive and metastasize. Although overwhelming evidence supports an acidic environment as a driver or ubiquitous hallmark of cancer progression, the unrevealed core mechanisms underlying the direct effect of acidification on tumorigenesis have hindered the discovery of novel therapeutic targets and clinical therapy. Here, chemical-induced and transgenic mouse models for colon, liver and lung cancer were established, respectively. miR-7 and TGF-β2 expressions were examined in clinical tissues (n = 184). RNA-seq, miRNA-seq, proteomics, biosynthesis analyses and functional studies were performed to validate the mechanisms involved in the acidic TME-induced lung cancer metastasis. Our data show that lung cancer is sensitive to the increased acidification of TME, and acidic TME-induced lung cancer metastasis via inhibition of miR-7-5p. TGF-β2 is a direct target of miR-7-5p. The reduced expression of miR-7-5p subsequently increases the expression of TGF-β2 which enhances the metastatic potential of the lung cancer. Indeed, overexpression of miR-7-5p reduces the acidic pH-enhanced lung cancer metastasis. Furthermore, the human lung tumor samples also show a reduced miR-7-5p expression but an elevated level of activated TGF-β2; the expressions of both miR-7-5p and TGF-β2 are correlated with patients’ survival. We are the first to identify the role of the miR-7/TGF-β2 axis in acidic pH-enhanced lung cancer metastasis. Our study not only delineates how acidification directly affects tumorigenesis, but also suggests miR-7 is a novel reliable biomarker for acidic TME and a novel therapeutic target for non-small cell lung cancer (NSCLC) treatment. Our study opens an avenue to explore the pH-sensitive subcellular components as novel therapeutic targets for cancer treatment.

Urban infrastructure resilience is an important perspective for measuring the development quality of resilient cities and an important way to measure the level of infrastructure development. This paper uses the kernel density estimation, exploratory spatial data analysis, and spatial econometric models to analyze the characteristics of dynamic evolution and the spillover effects of the infrastructure resilience levels in 283 prefecture-level and above cities in China from 2010 to 2019. Our results are as follows. (1) The overall level of urban infrastructure resilience increased. The eastern region had a higher level than the national average. In contrast, the central, western and north-eastern regions had a slightly lower level than the national average. (2) The areas with high and higher resilience levels were mostly cities with more developed economic and social conditions in Eastern China. The areas below moderate resilience levels show a certain degree of clustering and mainly include some cities in Central, Western, and Northeast China. (3) The national level of urban infrastructure resilience shows significant spatial clustering characteristics, and the spatial pattern from coastal to inland regions presents a hotspot-subhotspot-subcoldspot-coldspot distribution. (4) There is a differential spatial spillover effect of national urban infrastructure resilience, which is gradually strengthened under the role of the economy, financial development, population agglomeration and government funding and weakened under the role of urbanization, market consumption and infrastructure investment. By exploring the dynamic evolution of infrastructure resilience in cities at the prefecture level and above and its spatial spillover effects, we provide a scientific basis for avoiding the siphoning effect among cities, improving the level of infrastructure resilience, and guiding the construction and development of resilient cities.

Toosendanin (TSN) is a triterpenoid from the fruit or bark of Melia toosendan Sieb et Zucc, which has clear antitumor and insecticidal activities, but it possesses limiting hepatotoxicity in clinical application. Autophagy is a degradation and recycling mechanism to maintain cellular homeostasis, and it also plays an essential role in TSN-induced hepatotoxicity. Nevertheless, the specific mechanism of TSN on autophagy-related hepatotoxicity is still unknown. The hepatotoxicity of TSN in vivo and in vitro was explored in this study. It was found that TSN induced the upregulation of the autophagy-marker microtubule-associated proteins 1A/1B light chain 3B (LC3B) and P62, the accumulation of autolysosomes, and the inhibition of autophagic flux. The middle and late stages of autophagy were mainly studied. The data showed that TSN did not affect the fusion of autophagosomes and lysosomes but significantly inhibited the acidity, the degradation capacity of lysosomes, and the expression of hydrolase cathepsin B (CTSB). The activation of autophagy could alleviate TSN-induced hepatocyte damage. TSN inhibited the expression of transcription factor EB (TFEB), which is a key transcription factor for many genes of autophagy and lysosomes, such as CTSB, and overexpression of TFEB alleviated the autophagic flux blockade caused by TSN. In summary, TSN caused hepatotoxicity by inhibiting TFEB-lysosome-mediated autophagic flux and activating autophagy by rapamycin (Rapa), which could effectively alleviate TSN-induced hepatotoxicity, indicating that targeting autophagy is a new strategy to intervene in the hepatotoxicity of TSN.

Although artesunate has been reported to be a promising candidate for colorectal cancer (CRC) treatment, the underlying mechanisms and molecular targets of artesunate are yet to be explored. Here, we report that artesunate acts as a senescence and autophagy inducer to exert its inhibitory effect on CRC in a reactive oxygen species (ROS)-dependent manner. In SW480 and HCT116 cells, artesunate treatment led to mitochondrial dysfunction, drastically promoted mitochondrial ROS generation, and consequently inhibited cell proliferation by causing cell cycle arrest at G0/G1 phase as well as subsequent p16- and p21-mediated cell senescence. Senescent cells underwent endoplasmic reticulum stress (ERS), and the unfolded protein response (UPR) was activated via IRE1α signaling, with upregulated BIP, IRE1α, phosphorylated IRE1α (p-IRE1α), CHOP, and DR5. Further experiments revealed that autophagy was induced by artesunate treatment due to oxidative stress and ER stress. In contrast, N-Acetylcysteine (NAC, an ROS scavenger) and 3-Methyladenine (3-MA, an autophagy inhibitor) restored cell viability and attenuated autophagy in artesunate-treated cells. Furthermore, cellular free Ca2+ levels were increased and could be repressed by NAC, 3-MA, and GSK2350168 (an IRE1α inhibitor). In vivo, artesunate administration reduced the growth of CT26 cell-derived tumors in BALB/c mice. Ki67 and cyclin D1 expression was downregulated in tumor tissue, while p16, p21, p-IRE1α, and LC3B expression was upregulated. Taken together, artesunate induces senescence and autophagy to inhibit cell proliferation in colorectal cancer by promoting excessive ROS generation.

The trend towards efficient and intensive use of land resources is an inevitable outcome of current social development. The rational matching of urban land prices and land use intensity has become an important factor under accelerating urbanization, and promotes the healthy development of the social economy. Using data on residential land price and on land use intensity for 31 provinces and cities in China, we employ the E-G cointegration test and quadrant map classification to determine the coordination relationship between land price and land use intensity. We then employ HR coordination to calculate the coordination degree of land price and land use intensity, and classify the coordination type accordingly. Our results are as follows. (1) The spatio-temporal distribution of urban land price shows high variability with multiple maxima, and follows a decreasing trend from the southeast coastal area to the northwest inland area and the northeast. (2) The overall land use intensity is at or above the middle level, and shows large spatial differences between provinces, but the agglomeration between provinces is increasing. (3) From the perspective of the relationship between urban land price and land use intensity at the inter-provincial scale, we find that the land price and land use intensity are well coordinated, and the number of provinces has been dynamically changing during different development periods. There is an east-west difference in the spatial distribution of land price and land use intensity coordination level. Different provinces and cities with the same coordination stage show differences in their land price and land use intensity level.

Abstract Objective Coronary artery disease (CAD) is a multi-factor disease. Complement component 3 (C3) plays an important role in the development of CAD. The present study investigated the association between DNA methylation status of C3 gene promoter and the risk of CAD. Methods One hundred CAD patients and 1 hundred age-and gender- matched controls were recruited in current study. Methylation levels in CpG island in C3 promoter were determined by the method of bisulfite amplicon sequencing. Results Methylation levels of four CpG sites in C3 promoter were measured. There were no significant difference in methylation level of each CpG site between CAD patients and controls. Average methylation rate was also calculated. No significant difference in average methylation rate was observed between CAD and control groups. Stratified analyses based on EH, DM and smoking status were carried out, no significant association between C3 promoter methylation levels and the susceptibility of CAD was observed. Furthermore, seven haplotypes were established and no significant difference in haplotypes was observed between CAD and control groups. However, our study showed that C3 DNA methylation levels were positively associated with LDL-C levels. Conclusion The present study showed no association between methylation levels of C3 promoter and the risk of CAD. However, the methylation levels might be related to LDL-C levels.

Abstract Background Genetic and environment factors affect the occurrence and development of coronary artery disease (CAD). Proprotein convertase subtilisin/kexin type 9 (PCSK9), has been investigated extensively in the field of lipid metabolism and CAD. We performed this case-control study to investigate the relationship between serum PCSK9 levels and PCSK9 polymorphisms and lipid levels and CAD risk in a southern Chinese population. Methods A hospital-based case-control study with 1, 096 subjects, including 626 CAD patients and 470 controls, were conducted. Genotyping of PCSK9 polymorphisms was performed using polymerase chain reaction-ligase detection reaction (PCR-LDR) method. Results The frequencies of the AA, AG and GG genotypes of PCSK9 E670G polymorphism were 90.58, 9.27, and 0.16% in the CAD patients, compared with 88.72, 10.85 and 0.43% in the controls, respectively. No R46L variant was detected in this population. There were no significant differences in genotype and allele frequencies of PCSK9E670G polymorphism between the CAD group and the controls. Serum lipid levels were not significantly different in carriers with the G allele and those with the AA genotype. The median (QR) of PCSK9 concentration was 1205.00 ng/l (577.28–1694.13 ng/l) in cases and 565.87 ng/l (357.17–967.50 ng/l) in controls, respectively. Compared with controls, CAD patients had significantly higher PCSK9 levels (z = 4.559, P

The use of arginine deiminase (ADI) for arginine depletion therapy is an attractive anticancer approach. Combination strategies are needed to overcome the resistance of severe types of cancer cells to this monotherapy. In the current study, we report, for the first time, that the antioxidant N-acetylcysteine (NAC), which has been used in therapeutic practices for several decades, is a potent enhancer for targeted therapy that utilizes arginine deiminase. We demonstrated that pegylated arginine deiminase (ADI-PEG 20) induces apoptosis and G0/G1 phase arrest in murine MC38 colorectal cancer cells; ADI-PEG 20 induces Ca2+ overload and decreases the mitochondrial membrane potential in MC38 cells. ADI-PEG 20 induced the most important immunogenic cell death (ICD)-associated feature: cell surface exposure of calreticulin (CRT). The antioxidant NAC enhanced the antitumor activity of ADI-PEG 20 and strengthened its ICD-associated features including the secretion of high mobility group box 1 (HMGB1) and adenosine triphosphate (ATP). In addition, these regimens resulted in phagocytosis of treated MC38 cancer cells by bone marrow-derived dendritic cells (BMDCs). In conclusion, we describe, for the first time, that NAC in combination with ADI-PEG 20 not only possesses unique cytotoxic anticancer properties but also triggers the hallmarks of immunogenic cell death. Hence, ADI-PEG 20 in combination with NAC may represent a promising approach to treat ADI-sensitive tumors while preventing relapse and metastasis.

Peroxisome proliferator-activated receptors (PPARs), members of the nuclear hormone receptor family, attract wide attention as promising therapeutic targets for the treatment of multiple diseases, and their target selective ligands were also intensively developed for pharmacological agents such as the approved drugs fibrates and thiazolidinediones (TZDs). Despite their potent pharmacological activities, PPARs are reported to be involved in agent- and pollutant-induced multiple organ toxicity or protective effects against toxicity. A better understanding of the protective and the detrimental role of PPARs will help to preserve efficacy of the PPAR modulators but diminish adverse effects. The present review summarizes and critiques current findings related to PPAR-mediated types of toxicity and protective effects against toxicity for a systematic understanding of PPARs in toxicology and applied pharmacology.

The present study was performed to evaluate the food safety of TT51-1, a new type of genetically modified rice that expresses the Cry1Ab/Ac protein (Bt toxin) and is highly resistant to most lepidopteran pests. Sixteen male and 16 female cynomolgus monkeys were randomly divided into four groups: conventional rice (non-genetically modified rice, non-GM rice), positive control, 17.5% genetically modified rice (GM rice) and 70% GM rice. Monkeys in the non-GM rice, positive control, and GM rice groups were fed on diets containing 70% non-GM rice, 17.5% GM rice or 70% GM rice, respectively, for 182 days, whereas animals in the positive group were intravenously injected with cyclophosphamide every other day for a total of four injections before the last treatment. Six months of treatment did not yield abnormal observations. Specifically, the following parameters did not significantly differ between the non-GM rice group and GM rice groups: body weight, food consumption, electrocardiogram, hematology, immuno-phenotyping of lymphocytes in the peripheral blood, mitogen-induced peripheral blood lymphocyte proliferation, splenocyte proliferation, KLH-T cell-dependent antibody response, organ weights and ratios, and histological appearance (p>0.05). Animals from the GM rice group differed from animals in the non-GM rice group (p

Triptolide, the major active component of Tripterygium wilfordii Hook f. (TWHF), has a wide range of pharmacological activities. However, the toxicities of triptolide, particularly the hepatotoxicity, limit its clinical application. The hepatotoxicity of triptolide has not been well characterized yet. The aim of this study was to investigate the role of NF-E2-related factor 2 (Nrf2) in triptolide-induced toxicity and whether activation of Nrf2 could protect against triptolide-induced hepatotoxicity. The results showed that triptolide caused oxidative stress and cell damage in HepG2 cells, and these toxic effects could be aggravated by Nrf2 knockdown or be counteracted by overexpression of Nrf2. Treatment with a typical Nrf2 agonist, sulforaphane (SFN), attenuated triptolide-induced liver dysfunction, structural damage, glutathione depletion and decrease in antioxidant enzymes in BALB/C mice. Moreover, the hepatoprotective effect of SFN on triptolide-induced liver injury was associated with the activation of Nrf2 and its downstream targets. Collectively, these results indicate that Nrf2 activation protects against triptolide-induced hepatotoxicity.