Increased oxygen stimulation promotes chemoresistance and phenotype shifting through PLCB1 in gliomas.

Gliomas, the most common CNS (central nerve system) tumors, face poor survival due to severe chemoresistance exacerbated by hypoxia. However, studies on whether altered hypoxic conditions benefit for chemo-sensitivity and how gliomas react to increased oxygen stimulation are limited. In this study, we demonstrated that increased oxygen stimulation promotes glioma growth and chemoresistance. Mechanically, increased oxygen stimulation upregulates miR-1290 levels. miR-1290, in turn, downregulates PLCB1, while PLCB1 facilitates the proteasomal degradation of ß-catenin and active-ß-catenin by increasing the proportion of ubiquitinated ß-catenin in a destruction complex-independent mechanism. This process inhibits PLCB1 expression, leads to the accumulation of active-ß-catenin, boosting Wnt signaling through an independent mechanism and ultimately promoting chemoresistance in glioma cells. Pharmacological inhibition of Wnt by WNT974 could partially inhibit glioma volume growth and prolong the shortened survival caused by increased oxygen stimulation in a glioma-bearing mouse model. Moreover, PLCB1, a key molecule regulated by increased oxygen stimulation, shows promising predictive power in survival analysis and has great potential to be a biomarker for grading and prognosis in glioma patients. These results provide preliminary insights into clinical scenarios associated with altered hypoxic conditions in gliomas, and introduce a novel perspective on the role of the hypoxic microenvironment in glioma progression. Furthermore, the outcomes reveal the potential risks of utilizing hyperbaric oxygen treatment (HBOT) in glioma patients, particularly when considering HBOT as a standalone option to ameliorate neuro-dysfunctions or when combining HBOT with a single chemotherapy agent without radiotherapy.

Flower-Shaped PCR Scaffold-Based Lateral Flow Bioassay for Bacillus cereus Endospores Detection.

Bacillus cereus, a foodborne pathogen, produces resilient endospores that are challenging to detect with conventional methods. This study presents a novel Flower-Shaped PCR Scaffold-based Lateral Flow Biosensor (FSPCRS-LFB), which employs an aptamer-integrated PCR scaffold as capture probes, replacing the traditional streptavidin-biotin (SA-Bio) approach. The FSPCRS-LFB demonstrates high sensitivity and cost-efficiency in detecting B. cereus endospores, with a limit of detection (LOD) of 4.57 endospores/mL a visual LOD of 102 endospores/mL, and a LOD of 6.78 CFU/mL for endospore-cell mixtures. In chicken and tea samples, the platform achieved LODs of 74.5 and 52.8 endospores/mL, respectively, with recovery rates of 82.19% to 97.88%. Compared to existing methods, the FSPCRS-LFB offers a 3.7-fold increase in sensitivity while reducing costs by 26% over the SA-Bio strategy and 87.5% over rolling circle amplification (RCA). This biosensor provides a rapid, sensitive and cost-effective solution for point-of-care testing (POCT) of B. cereus endospores, expanding detection capabilities and offering novel approaches for pathogen detection.

Resistin-like molecules: a marker, mediator and therapeutic target for multiple diseases.

Resistin-like molecules (RELMs) are highly cysteine-rich proteins, including RELMα, RELMß, Resistin, and RELMγ. However, RELMs exhibit significant differences in structure, distribution, and function. The expression of RELMs is regulated by various signaling molecules, such as IL-4, IL-13, and their receptors. In addition, RELMs can mediate numerous signaling pathways, including HMGB1/RAGE, IL-4/IL-4Rα, PI3K/Akt/mTOR signaling pathways, and so on. RELMs proteins are involved in wide range of physiological and pathological processes, including inflammatory response, cell proliferation, glucose metabolism, barrier defense, etc., and participate in the progression of numerous diseases such as lung diseases, intestinal diseases, cardiovascular diseases, and cancers. Meanwhile, RELMs can serve as biomarkers, risk predictors, and therapeutic targets for these diseases. An in-depth understanding of the role of RELMs may provide novel targets or strategies for the treatment and prevention of related diseases. Video abstract.

Mechanisms of dihydromyricetin against hepatocellular carcinoma elucidated by network pharmacology combined with experimental validation.

CONTEXT: Dihydromyricetin (DMY) is extracted from vine tea, a traditional Chinese herbal medicine with anti-cancer, liver protection, and cholesterol-lowering effects. OBJECTIVE: This study investigated the mechanism of DMY against hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Potential DMY, HCC, and cholesterol targets were collected from relevant databases. PPI networks were created by STRING. Then, the hub genes of co-targets, screened using CytoHubba. GO and KEGG pathway enrichment, were performed by Metascape. Based on the above results, a series of in vitro experiments were conducted by using 40-160 µM DMY for 24 h, including transwell migration/invasion assay, western blotting, and Bodipy stain assay. RESULTS: Network pharmacology identified 98 common targets and 10 hub genes of DMY, HCC, and cholesterol, and revealed that the anti-HCC effect of DMY may be related to the positive regulation of lipid rafts. Further experiments confirmed that DMY inhibits the proliferation, migration, and invasion of HCC cells and reduces their cholesterol levels in vitro. The IC50 is 894.4, 814.4, 467.8, 1,878.8, 151.8, and 156.9 µM for 97H, Hep3B, Sk-Hep1, SMMC-7721, HepG2, and Huh7 cells, respectively. In addition, DMY downregulates the expression of lipid raft markers (CAV1, FLOT1), as well as EGFR, PI3K, Akt, STAT3, and Erk. DISCUSSION AND CONCLUSION: The present study reveals that DMY suppresses EGFR and its downstream pathways by reducing cholesterol to disrupt lipid rafts, thereby inhibiting HCC, which provides a promising candidate drug with low toxicity for the treatment of HCC.

Targeting HDL in tumor microenvironment: New hope for cancer therapy.

Epidemiological studies have shown that plasma HDL-C levels are closely related to the risk of prostate cancer, breast cancer, and other malignancies. As one of the key carriers of cholesterol regulation, high-density lipoprotein (HDL) plays an important role in tumorigenesis and cancer development through anti-inflammation, antioxidation, immune-modulation, and mediating cholesterol transportation in cancer cells and noncancer cells. In addition, the occurrence and progression of cancer are closely related to the alteration of the tumor microenvironment (TME). Cancer cells synthesize and secrete a variety of cytokines and other factors to promote the reprogramming of surrounding cells and shape the microenvironment suitable for cancer survival. By analyzing the effect of HDL on the infiltrating immune cells in the TME, as well as the relationship between HDL and tumor-associated angiogenesis, it is suggested that a moderate increase in the level of HDL in vivo with consequent improvement of the function of HDL in the TME and induction of intracellular cholesterol efflux may be a promising strategy for cancer therapy.

Celastrol suppresses lipid accumulation through LXRα/ABCA1 signaling pathway and autophagy in vascular smooth muscle cells.

The uptake of modified low-density lipoprotein (LDL) and the accumulation of lipid droplets induce the formation of vascular smooth muscle cells (VSMCs)-derived foam cells, thereby promoting the development and maturation of plaques and accelerating the progression of atherosclerosis. Celastrol is a quinine methide triterpenoid isolated from the root bark of traditional Chinese herb Tripterygium wilfordii. It possesses various biological properties, including anti-obesity, cardiovascular protection, anti-inflammation, etc. In the present study, we found that celastrol significantly reduced lipid accumulation induced by oxidized LDL (ox-LDL) in VSMCs. Mechanistically, celastrol up-regulated adenosine triphosphate-binding cassette transporter A1 (ABCA1) expression through activating liver X receptor α (LXRα) expression, which contributed to inhibit lipid accumulation in VSMCs. Meanwhile, celastrol decreased lipid accumulation by triggering autophagy in VSMCs. Therefore, these findings supported celastrol as a potentially effective agent for the prevention and therapy of atherosclerosis.

The crosstalk: exosomes and lipid metabolism.

Exosomes have been considered as novel and potent vehicles of intercellular communication, instead of "cell dust". Exosomes are consistent with anucleate cells, and organelles with lipid bilayer consisting of the proteins and abundant lipid, enhancing their "rigidity" and "flexibility". Neighboring cells or distant cells are capable of exchanging genetic or metabolic information via exosomes binding to recipient cell and releasing bioactive molecules, such as lipids, proteins, and nucleic acids. Of note, exosomes exert the remarkable effects on lipid metabolism, including the synthesis, transportation and degradation of the lipid. The disorder of lipid metabolism mediated by exosomes leads to the occurrence and progression of diseases, such as atherosclerosis, cancer, non-alcoholic fatty liver disease (NAFLD), obesity and Alzheimer's diseases and so on. More importantly, lipid metabolism can also affect the production and secretion of exosomes, as well as interactions with the recipient cells. Therefore, exosomes may be applied as effective targets for diagnosis and treatment of diseases. Video abstract.

Identification and characterization of a novel phthalate-degrading hydrolase from a soil metagenomic library.

Phthalate esters have raised public concerns owing to their effects on the environment and human health. We identified a novel phthalate-degrading hydrolase, EstJ6, from a metagenomic library using function-driven screening. Phylogenetic analysis indicated that EstJ6 is a member of family IV esterases. EstJ6 hydrolyzed various dialkyl and monoalkyl phthalate esters, and exhibited high hydrolytic activity (128 U/mg) toward dibutyl phthalate at 40 °C and pH 7.5. EstJ6 hydrolyzed not only common phthalate esters with simple side chains but also diethylhexyl phthalate and monoethylhexyl phthalate, which have complex and long side chains. Site-directed mutagenesis indicated that the catalytic triad residues of EstJ6 consists of Ser146, Glu240, and His270. EstJ6 is therefore a promising biodegradation enzyme, and our study illustrates the advantages of a metagenomic approach in identifying enzyme-coding genes for agricultural, food, and biotechnological applications.

Genistein Protects H9c2 Cardiomyocytes against Chemical Hypoxia-Induced Injury via Inhibition of Apoptosis.

BACKGROUND/AIMS: Hypoxia can induce cell injury in cardiomyocytes and further lead to cardiovascular diseases. Genistein (Gen), the predominant isoflavone found in soy products, has shown protective effects on cardiovascular system. The aim of the present study was to investigate the cardioprotective effect of Gen against chemical hypoxia-induced injury. METHODS: Cobalt chloride (CoCl2) was administrated to trigger chemical hypoxia in H9c2 cardiomyocytes. Cell proliferation was detected by using MTT assay. The expression level of hypoxia-related proteins (hypoxia-inducible factor [HIF]-1α and Notch-1) and apoptosis-related proteins (B cell lymphoma [Bcl]-2, Bax, and caspase-3) were evaluated by Western blot analysis. RESULTS: In response to hypoxia, cell viability was reduced dramatically, whereas the expression of HIF-1α was upregulated. Hypoxia also induced cardiomyocytes apoptosis by reducing the ratio of Bcl-2/Bax and increasing expression of caspase-3. Interestingly, Gen attenuated CoCl2-induced cell death and suppressed HIF-1α expression, as well as upregulated the expression of Notch-1. Furthermore, Gen could antagonize CoCl2-induced apoptosis through upregulating Bcl-2/Bax ratio and inhibiting caspase-3 expression. CONCLUSIONS: Gen prevents chemical hypoxia-induced cell apoptosis through inhibition of the mitochondrial apoptotic pathway, exerting protective effects on H9c2 cardiomyocytes.

[Molecular mechanism of vascular remodeling in hypertension and Chinese medicine intervention].

Vascular remodeling is a significant pathological characteristic of hypertension, which is regulated by complex regulatory networks. The vascular remodeling may be adaptive initially, however it becomes maladaptive and decompensation eventually and further compromises target organ function, leading to hypertensive cardiovascular complications. This review focuses on the role and mechanisms of vascular remodeling in the pathogenesis and progression of hypertension and its complications. Moreover, the strategies of syndrome differentiation of traditional Chinese medicine application provide clinical and theoretical evidences for hypertensive vascular remodeling therapy. A better understanding of underlying signaling pathways, therapeutic targets in vascular remodeling, as well as screening of active ingredients from traditional Chinese medicine may be able to provide some effective approaches for vascular protection in hypertensive diseases.

Caveolae and Caveolin-1 Integrate Reverse Cholesterol Transport and Inflammation in Atherosclerosis.

Lipid disorder and inflammation play critical roles in the development of atherosclerosis. Reverse cholesterol transport is a key event in lipid metabolism. Caveolae and caveolin-1 are in the center stage of cholesterol transportation and inflammation in macrophages. Here, we propose that reverse cholesterol transport and inflammation in atherosclerosis can be integrated by caveolae and caveolin-1.

d-Mannose: Properties, Production, and Applications: An Overview.

d-Mannose is a C-2 epimer of d-glucose, which is a natural monosaccharide. It can be obtained from both plants and microorganisms. Chemical synthesis and biotransformation of d-mannose from d-fructose or d-glucose by using d-mannose isomerases, d-lyxose isomerases, and cellobiose 2-epimerase were intensively studied. d-Mannose is an important component of polysaccharides and glycoproteins. It has been widely used in the food, pharmaceutical, and poultry industries, acting as the source of dietary supplements, starting material for the synthesis of drugs and blocking colonization in animal feeds. d-Mannose is a glyconutrient with high research value in basic science because of its structure and function. This article presents a review of current studies on sources, characteristics, production, and application of d-mannose.

Synthesis and Structure of a Ternary Copper(II) Complex with Mixed Ligands of Diethylenetriamine and Picrate: DNA/Protein-Binding Property and In Vitro Anticancer Activity Studies.

Based on the importance of the design and synthesis of transition metal complexes with noncovalent DNA/protein-binding abilities in the field of metallo pharmaceuticals, a new mononuclear ternary copper(II) complex with mixed ligands of diethylenetriamine (dien) and picrate anion (pic), identified as [Cu(dien)(pic)](pic), was synthesized and characterized by elemental analysis, molar conductivity measurement, infrared spectrum, electronic spectral studies, and single-crystal X-ray diffractometry. The structure analysis reveals that the copper(II) complex crystallizes in the monoclinic space group P21 /c, and the copper(II) ion has a distorted square pyramidal coordination geometry. A two-dimensional supramolecular structure is formed through hydrogen bonds. The DNA/bovine serum albumin (BSA)-binding properties of the complex are explored, indicating that the complex can interact with herring sperm DNA via intercalation mode and bind to BSA responsible for quenching of tryptophan fluorescence by static quenching mechanism. The in vitro anticancer activity shows that the copper(II) complex is active against the selected tumor cell lines.

Hydrolysate from eggshell membrane ameliorates intestinal inflammation in mice.

Inflammatory bowel diseases (IBD) comprises of ulcerative colitis (UC) and Cohn's disease (CD) as two main idiopathic pathologies resulting in immunologically mediated chronic inflammatory conditions. Several bioactive peptides and hydro lysates from natural sources have now been tested in animal models of human diseases for potential anti-inflammatory effects. Eggshell membrane (ESM) is a well-known natural bioactive material. In this study, we aim to study the anti-inflammatory activity of ESM hydro lysate (AL-PS) in vitro and in vivo. In vitro, AL-PS was shown to inhibit pro-inflammatory cytokine IL-8 secretion. In vivo treatment with AL-PS was shown to reduce dextran sodium sulphate (DSS)-induced weight loss, clinical signs of colitis and secretion of interleukin (IL)-6 (p < 0.05). In addition, treatment with AL-PS also attenuated the severity of intestinal inflammation via down-regulation of IL-10 an anti-inflammatory cytokine. This validates potential benefits of AL-PS as a novel preventative target molecule for treatment of IBD.

Lipids and lipid metabolism in cellular senescence: Emerging targets for age-related diseases.

Cellular senescence is a kind of cellular state triggered by endogenous or exogenous stimuli, which is mainly characterized by stable cell cycle arrest and complex senescence-associated secretory phenotype (SASP). Once senescent cells accumulate in tissues, they may eventually accelerate the progression of age-related diseases, such as atherosclerosis, osteoarthritis, chronic lung diseases, cancers, etc. Recent studies have shown that the disorders of lipid metabolism are not only related to age-related diseases, but also regulate the cellular senescence process. Based on existing research evidences, the changes in lipid metabolism in senescent cells are mainly concentrated in the metabolic processes of phospholipids, fatty acids and cholesterol. Obviously, the changes in lipid-metabolizing enzymes and proteins involved in these pathways play a critical role in senescence. However, the link between cellular senescence, changes in lipid metabolism and age-related disease remains to be elucidated. Herein, we summarize the lipid metabolism changes in senescent cells, especially the senescent cells that promote age-related diseases, as well as focusing on the role of lipid-related enzymes or proteins in senescence. Finally, we explore the prospect of lipids in cellular senescence and their potential as drug targets for preventing and delaying age-related diseases.

Celastrol mediates CAV1 to attenuate pro-tumorigenic effects of senescent cells.

BACKGROUND: Cellular senescence is an emerging hallmark of cancers, primarily fuels cancer progression by expressing senescence-associated secretory phenotype (SASP). Caveolin-1 (CAV1) is a key mediator of cell senescence. Previous studies from our group have evidenced that the expression of CAV1 is downregulated by Celastrol (CeT). PURPOSE: To investigate the impact of CeT on cellular senescence and its subsequent influence on post-senescence-driven invasion, migration, and stemness of clear cell renal cell carcinoma (ccRCC). STUDY DESIGN AND METHODS: The expression levels of CAV1, canonical senescence markers, and markers associated with epithelial-mesenchymal transition (EMT) and stemness in clinical samples were assessed through Pearson correlation analysis. Senescent cell models were induced using DOX, and their impact on migration, invasion, and stemness was evaluated. The effects of CeT treatment on senescent cells and their pro-tumorigenic effects were examined. Subsequently, the underlying mechanism of CeT were explored using lentivirus transfection and CRISPR/Cas9 technology to silence CAV1. RESULTS: In human ccRCC clinical samples, the expression of the canonical senescence markers p53, p21, and p16 are associated with ccRCC progression. Senescent cells facilitated migration, invasion, and enhanced stemness in both ccRCC cells and ccRCC tumor-bearing mice. As expected, CeT treatment reduced senescence markers (p16, p53, p21, SA-ß-gal) and SASP factors (IL6, IL8, CXCL12), alleviating cell cycle arrest. However, it did not restore the proliferation of senescent cells. Additionally, CeT suppressed senescence-driven migration, invasion, and stemness. Further investigations into the underlying mechanism demonstrated that CAV1 is a critical mediator of cell senescence and represents a potential target for CeT to attenuate cellular senescence. CONCLUSIONS: This study presents a pioneering investigation into the intricate interplay between cellular senescence and ccRCC progression. We unveil a novel mechanism of CeT to mitigate cellular senescence by downregulating CAV1, thereby inhibiting the migration, invasion and stemness of ccRCC driven by senescent cells. These findings provide valuable insights into the underlying mechanisms of CeT and its potential as a targeted therapeutic approach for alleviating the aggressive phenotypes associated with senescent cells in ccRCC.

Protective effect of naringenin on cadmium chloride-induced renal injury via alleviating oxidative stress, endoplasmic reticulum stress, and autophagy in chickens.

Cadmium (Cd) is a highly hazardous toxic substance that can cause serious harm to animals. Previous studies have indicated that cadmium chloride (CdCl2) can damage organs, such as the liver, ovaries, and testicles. Naringenin (Nar) represents a flavonoid with various properties that promote the alleviation of Cd-induced damage. In this experiment, 60 chickens were divided into the control group, 150 mg/kg CdCl2 treatment group, 250 mg/kg Nar treatment group, and 150 mg/kg CdCl2 + 250 mg/kg Nar co-treatment group, which were treated for 8 weeks. Kidney tissues samples were collected to investigate kidney function, including oxidative stress (OS), endoplasmic reticulum (ER) stress, and autophagy activity. Experimental results showed the decreased weight of chickens and increased relative weight of their kidneys after CdCl2 treatment. The increase in NAG, BUN, Cr, and UA activities, as well as the increase in MDA and GSH contents, and the decrease activities of T-AOC, SOD, and CAT in the kidney, manifested renal injury by OS in the chickens. TUNEL staining revealed that CdCl2 induced apoptosis in renal cells. CdCl2 upregulates the mRNA and protein expression levels of GRP78, PERK, eIF2α, ATF4, ATF6, CHOP, and LC3, and inhibited the mRNA and protein expression levels of P62 proteins, which leads to ER stress and autophagy. The CdCl2 + Nar co-treatment group exhibited alleviated CdCl2-induced kidney injury, OS, ER stress, and autophagy. Research has demonstrated that Nar reduces CdCl2-induced kidney injury through alleviation of OS, ER stress, and autophagy.

Celastrol Elicits Antitumor Effects through Inducing Immunogenic Cell Death and Downregulating PD-L1 in ccRCC.

BACKGROUND: Targeting immunogenic cell death (ICD) is considered a promising therapeutic strategy for cancer. However, the commonly identified ICD inducers promote the expression of programmed cell death ligand 1 (PD-L1) in tumor cells, thus aiding them to evade the recognition and killing by the immune system. Therefore, the finding of novel ICD inducers to avoid enhanced PD-L1 expression is of vital significance for cancer therapy. Celastrol (CeT), a triterpene isolated from Tripterygium wilfordii Hook. F induces various forms of cell death to exert anti-cancer effects, which may make celastrol an attractive candidate as an inducer of ICD. METHODS: In the present study, bioinformatics analysis was combined with experimental validation to explore the underlying mechanism by which CeT induces ICD and regulates PD-L1 expression in clear cell renal cell carcinoma (ccRCC). RESULTS: The results showed that EGFR, IKBKB, PRKCQ and MAPK1 were the crucial targets for CeT-induced ICD, and only MAPK1 was an independent prognostic factor for the overall survival (OS) of ccRCC patients. In addition, CeT triggered autophagy and up-regulated the expressions of HMGB1 and CRT to induce ICD in 786-O cells in vitro. Importantly, CeT can down-regulate PD-L1 expression through activating autophagy. At the molecular level, CeT suppressed PD-L1 via the inhibition of MAPK1 expression. Immunologically, the core target of celastrol, MAPK1, was tightly correlated with CD8+ T cells and CD4+ T cells in ccRCC. CONCLUSION: These findings indicate that CeT not only induces ICD but also suppresses PD-L1 by down-regulating MAPK1 expression, which will provide an attractive strategy for ccRCC immunotherapy.

Quercetin attenuates cadmium-induced hepatotoxicity by suppressing oxidative stress and apoptosis in rat.

BACKGROUND: Cadmium (Cd) is considered a major industrial and environmental toxicant, threatening the health of aquatic organisms, plants, animals, and humans. Quercetin (Que) is a natural flavonoid with antioxidant properties. The purpose of this study was to investigate the role of the oxidative stress and apoptosis in Cd-induced hepatotoxicity and the protective effect of Que. METHODOLOGY: Thirty-six male SD rats were randomly divided into 6 groups: control group, 1 mg/kg Cd group, 2 mg/kg Cd group, 1 mg/kg Cd+Que group, 2 mg/kg Cd + Que group, and a Que group. After a feeding period of 28 days, serum and liver tissue samples were collected to evaluate liver function, oxidative stress levels, liver histology, and apoptosis. RESULTS: Experimental results confirmed that compared with the control group, the body weights of the Cd group significantly decreased. Additionally, there was a tremendous increased in the levels of ALT, AST, and LDH, and a significant decreased in the activities of SOD, CAT, and GSH content, while the level of MDA increased. Pathological sections of the liver showed that Cd-induced rats had ruptured liver tissue cells, exposed nuclei, and disturbed arrangement of hepatocyte cords. Cd exposure decreased the mRNA and protein expression of Nrf2 and NQO1 while increased the mRNA and protein expression of Keap1, thereby inducing oxidative stress. Meanwhile, Cd exposure increased the mRNA and protein expressions of Cytc, caspase-9, caspase-3, and Bax, while decreased the expression of Bcl-2. Conversely, after Que addition of alleviated liver injury and oxidative stress induced by Cd and inhibited apoptosis. CONCLUSION: In conclusion, Que alleviates hepatic toxicity induced by Cd through suppression of oxidative stress and apoptosis.

Roles of Cyt-c/Caspase-9/Caspase-3/Bax/Bcl-2 pathway in Cd-induced testicular injury in rats and the protective effect of quercetin.

Cadmium (Cd) exposure causes oxidative damage to mitochondria, which would adversely affect rat testicular tissue. Quercetin (Que) is a natural antioxidant with anti-inflammatory, antioxidant and anti-apoptotic effects. However, the mechanism by which Que inhibits Cd-induced apoptosis of testicular cells remains unclear. The purpose of this study was to investigate the role of mitochondrial apoptosis pathway (Cyt-c/Caspase-9/Caspase-3/Bax/Bcl-2 pathway) in inhibiting Cd-induced apoptosis of testicular cells by Que. We used SD rats to simulate Cd chloride exposure by treating all sides of the rats with CdCl2 and/or Que. The levels of GSH and MDA in rat testis were detected using reagent kits. The effects of CdCl2 and/or Que on tissue damage, apoptosis, and gene and protein expression of the Cyt-c/Caspase-9/Caspase-3/Bax/Bcl-2 pathway in rat testis were examined by HE, TUNEL, RNA extraction and reverse-transcriptase polymerase chain reaction (RT-PCR), and Western blot (Wb). The results show that Cd significantly increased the contents of GSH and MDA in rat testis (P < 0.01); conversely, Que significantly reduced the contents of GSH and MDA (P < 0.01). Cd inflicted damage to testicular tissue, and Que addition significantly reduced the damage. Cd increased the number of apoptosis of testicle cells, and Que inhibited testicle-cell apoptosis. In addition, the results of reverse transcription PCR and Wb assays confirmed that, as expected, Cd increased the expression levels of Cyt-c, Caspase-9, Caspase-3, and Bax mRNAs as well as proteins. And at the same time decreased the expression of the anti-apoptotic factor Bcl-2 in the cells. Surprisingly, these effects were reversed when Que was added. Therefore, Que can play an antioxidant and anti-apoptotic role in reducing the testicular tissue damage caused by Cd exposure. This provides a conceptual basis for the later development and utilization of Que as well as the prevention and treatment of tissue damage caused by Cd exposure.