Gut bacterial microbiota of Lymantria dispar asiatica and its involvement in Beauveria bassiana infection.

The gut bacterial microbiota of insects has been shown to play essential roles in processes related to physiology, metabolism, and innate immunity. In this study, we firstly performed a broad analysis of the gut bacteria in Lymantria dispar asiatica, one of the most devastating forestry defoliators. We analyzed the bacterial composition among different individuals from lab-reared or wild-collected using 16 s rRNA-sequencing, revealing that the gut bacteria of wild-collected larvae were highly diverse, while lab-reared larvae were only associated with a few genera. We found Lactobacillus sp. present in all the gut samples, which indicates that it is part of the core microbiome in the caterpillar. Further Beauveria bassiana infection-based assays showed that the mortality of non-axenic L. dispar asiatica larvae was significantly higher than that of axenic larvae at 72 h. Moreover, we isolated several bacteria from the hemolymph of the non-axenic larvae infected by B. bassiana, which may be caused by the translocation of gut bacteria from the gut to the hemocoel. Reintroduction of Enterococcus sp., Pseudomonas sp., Enterobacter sp., and Microbacterium sp. into axenic larvae recurred the larval mortality in their non-axenic counterpart. Taken together, our study demonstrates that the gut bacteria of L. dispar asiatica are highly volatile, and different bacteria taxa can promote host infection by entomopathogenic fungus, providing a new strategy for the pest management.

Functional analysis of 3 genes in xenobiotic detoxification pathway of Bursaphelenchus xylophilus against matrine.

Bursaphelenchus xylophilus is the causative agent of pine wilt disease. It has caused devastating damage to ecosystems worldwide, owing to the characteristic of being widely spread and uncontrollable. However, the current methods of control are mainly based on pesticides, which can cause irreversible damage to the ecosystem. Therefore, the search for new drug targets and the development of environmentally friendly nematicides is especially valuable. In this study, three key genes of the xenobiotic detoxification pathways were cloned from B. xylophilus, which were subsequently subjected to bioinformatic analysis. The bioassay experiment was carried out to determine the concentration of matrine required for further tests. Subsequently, enzyme activity detection and three gene expression pattern analysis were performed on matrine treated nematodes. Finally, RNA interference was conducted to verify the functions carried out by the three genes in combating matrine. The results indicated that cytochrome P450 and glutathione S-transferase of B. xylophilus were activated by matrine, which induced high expression of BxCYP33C4, BxGST1, and BxGST3. After RNA interference of three genes of B. xylophilus, the sensitivity of B. xylophilus to matrine was increased and the survival rate of nematodes was reduced to various degrees in comparison to the control group. Overall, the results fully demonstrated that BxCYP33C4, BxGST1, and BxGST3 are valuable drug targets for B. xylophilus. Furthermore, the results suggested that matrine has value for development and exploitation in the prevention and treatment of B. xylophilus.

Comprehensive Analysis of Universal Stress Protein Family Genes and Their Expression in Fusarium oxysporum Response of Populus davidiana × P. alba var. pyramidalis Louche Based on the Transcriptome.

Universal stress proteins (USPs) are typical stress-inducible proteins that function directly in a variety of biotic or abiotic stresses and effectively protect plants from complex, adverse environments. However, the expression patterns of USP genes under pathogen stress and their molecular mechanisms in stress resistance have not been reported in detail. In this study, 46 USP genes were identified from Populus trichocarpa (PtrUSPs), and their biological characteristics were comprehensively analyzed based on phylogeny, physicochemical properties of proteins, and gene structures. The promoter regions of PtrUSPs contain a variety of cis-acting elements related to hormone and stress response. The results of a collinearity analysis showed that PtsrUSPs were highly conserved with homologous genes from four other representative species (Arabidopsis thaliana, Eucalyptus grandis, Glycine max, and Solanum lycopersicum). Furthermore, RNA-Seq analysis showed that the expression of 46 USPs from P. davidiana × P. alba var. pyramidalis Louche (PdpapUSPs) was significantly induced by Fusarium oxysporum. The co-expression network and gene ontology analysis of PtrUSPs showed that they participated in the response to stress and response to stimulus through precise coordination. The results of this paper systematically revealed the biological characteristics of PtrUSPs and the characteristics of their response to F. oxysporum stress, which will lay a theoretical foundation for improving genetic traits and the breeding of poplar disease-resistant varieties in subsequent studies.

Aberrant Notch signalling contributes to hypertrophic scar formation by modulating the phenotype of keratinocytes.

Hypertrophic scar (HS) is characterized by fibroblast hyperproliferation and excessive matrix deposition. Aberrant keratinocyte differentiation and their abnormal cytokine secretion are said to contribute to HS by activating fibroblasts. However, the signalling pathway causing the aberrant keratinocytes in HS has remained unidentified thus far. Given that Notch signalling is crucial in initiating keratinocyte differentiation, we hypothesized that Notch signalling contributes to HS by modulating the phenotype of keratinocytes. We found that Notch1, Notch intracellular domain, Jagged1 and Hes-1 were overexpressed in the epidermis of patients with HS. Supernatants from recombinant-Jagged1-treated keratinocyte cultures could accelerate dermal fibroblast proliferation and collagen production. Furthermore, Jagged1 induced keratinocyte differentiation and upregulated the expression of fibrotic factors, including transforming growth factors ß1 and ß2 , insulin-like growth factor-1, connective tissue growth factor, vascular endothelial growth factor and epidermal growth factor, while DAPT (a Notch inhibitor) significantly suppressed these processes. In a rabbit ear model of HS, local application of DAPT downregulated the production of fibrotic factors in keratinocytes, together with ameliorated scar hyperplasia. Our findings suggest that Notch signalling contributes to HS by modulating keratinocyte phenotype. These results provide new insights into the pathogenesis of HS and indicate a potential therapeutic target.

[Effect of curcumin on radiosensitization of CNE-2 cells and its mechanism].

OBJECTIVE: To investigate the effect of curcumin (Cur) on radiosensitivity of nasopharyngeal carcinoma cell CNE-2 and its mechanism. METHOD: The effect of curcumin on radiosensitivity was determined by the clone formation assay. The cell survival curve was fitted by Graph prism 6. 0. The changes in cell cycle were analyzed by flow cytometry (FCM). The differential expression of long non-coding RNA was detected by gene chip technology. Part of differentially expressed genes was verified by Real-time PCR. RESULT: After 10 micro mol L-1 Cur had worked for 24 h, its sensitization enhancement ratio was 1. 03, indicating that low concentration of curcumin could increase the radiosensitivity of nasopharyngeal carcinoma cells; FCM displayed a significant increase of G2 phase cells and significant decrease of S phase cells in the Cur combined radiation group. In the Cur group, the GUCY2GP, H2BFXP, LINC00623 IncRNA were significantly up-regulated and ZRANB2-AS2 LOC100506835, FLJ36000 IncRNA were significantly down-regulated. CONCLUSION: Cur has radiosensitizing effect on human nasopharyngeal carcinoma CNE-2 cells. Its mechanism may be related to the changes in the cell cycle distribution and the expression of long non-coding IncRNA.

Pathogenesis mechanisms of phytopathogen effectors.

Plants commonly face the threat of invasion by a wide variety of pathogens and have developed sophisticated immune mechanisms to defend against infectious diseases. However, successful pathogens have evolved diverse mechanisms to overcome host immunity and cause diseases. Different cell structures and unique cellular organelles carried by plant cells endow plant-specific defense mechanisms, in addition to the common framework of innate immune system shared by both plants and animals. Effectors serve as crucial virulence weapons employed by phytopathogens to disarm the plant immune system and promote infection. Here we summarized the many diverse strategies by which phytopathogen effectors overcome plant defense and prospected future perspectives. This article is categorized under: Infectious Diseases > Molecular and Cellular Physiology.

Marital status is an independent prognostic factor for cervical adenocarcinoma: A population-based study.

Marriage has been reported as a beneficial factor associated with improved survival among cancer patients, but conflicting results have been observed in cervical adenocarcinoma (AC). Thus, this study is aimed to examine the relationship between the prognosis of cervical AC and marital status. Eligible patients were selected from 2004 to 2015 using the surveillance, epidemiology and end results (SEER) database. Cancer-specific survival (CSS) and overall survival (OS) were compared between married and unmarried groups. A total of 3096 patients had been identified, with married ones accounting for 51.29% (n = 1588). Compared to unmarried groups, more patients in the married group were relatively younger (aged ≤ 45) and belonged to white race, with grade I/II, Federation of International of Gynecologists and Obstetricians (FIGO) stage I/II and tumor size ≤4 cm. Apart from that, more patients received surgery, whereas fewer patients received chemotherapy and radiotherapy (all P < 0.05). The 5-year CSS and OS rates were 80.16% and 78.26% in married patients, 68.58% and 64.62% in the unmarried group (P < .0001). Multivariate analysis showed that marital status was an independent prognostic factor, and the married group performed better CSS (hazard ratio [HR]: 0.770; 95% confidence interval [CI]: 0.663-0.895; P = .001) as well as OS (HR: 0.751; 95%CI: 0.653-0.863; P < .001). As demonstrated by the results of subgroup analysis, married patients had better CSS and OS survival than unmarried ones in nearly all the subgroups. Marital status was identified as an independent prognostic factor for improved survival in patients with cervical AC.

A nomogram for the prediction of survival for colorectal signet ring cell carcinoma after surgery: A population-based study.

The aim was to construct and verify a nomogram-based assessment of cancer-specific survival (CSS) in patients with colorectal signet ring cell carcinoma after surgery. Patients were collected from Surveillance, Epidemiology, and End Results program between 2004 and 2015. Independent prognostic indicators were determined in the training cohort by Cox regression model. We identified 2217 eligible patients, who were further categorized into the training set (n = 1693) as well as the validation set (n = 524). Multivariate analysis revealed that age at diagnosis, gender, grade, tumor size, T stage, N stage, and M stage were independent predictive indicators. Then, the above 7 predictive factors were incorporated into a nomogram model to assess CSS, which showed good calibration and discrimination capacities in both sets. Both internal and external calibration plot diagrams revealed that the actual results were consistent with the predicted outcomes. The time-independent area under the curves for 3-year and 5-year CSS in the nomogram were larger than American Joint Committee on Cancer and Surveillance, Epidemiology, and End Results summary stage system. Moreover, decision curve analysis indicated the clinical utility of the nomogram. The nomogram demonstrated favorable predictive accuracy of survival in colorectal signet ring cell carcinoma patients after surgery, which should be further confirmed before clinical implementation.

Development and validation of a nomogram to predict overall survival for cervical adenocarcinoma: A population-based study.

This study aimed to develop and validate a nomogram for predicting the overall survival of cervical adenocarcinoma (CAC) patients using a large database comprising patients with different ethnicities. We enrolled primary CAC cases with complete clinicopathological and survival data from the Surveillance, Epidemiology, and End Results program during 2004 to 2015. For training set samples, this work applied the Cox regression model to obtain factors independently associated with patient prognosis, which could be incorporated in constructing the nomogram. Altogether 3096 qualified cases were enrolled, their survival ranged from 0 to 155 (median, 45.5) months. As revealed by multivariate regression, age, marital status, tumor size, grade, International Federation of Gynecology and Obstetrics (FIGO) classification, pelvic lymph node metastasis, surgery, and chemotherapy served as the factors to independently predict CAC (all P < .05). We later incorporated these factors for constructing the nomogram. According to the concordance index determined, this nomogram had superior discrimination over FIGO classification system (all P < .001). Based on calibration plot, the predicted value was consistent with actual measurement. As revealed by time-independent area under the curves, our constructed nomogram had superior 5-year overall survival over FIGO system. Additionally, according to decision curve analysis, our constructed nomogram showed high clinical usefulness as well as favorable discrimination. Our constructed nomogram attains favorable performances, indicating that it may be applied in predicting survival for CAC patients.

Chiral recognition of metalaxyl enantiomers by human serum albumin: evidence from molecular modeling and photophysical approach.

Metalaxyl is an acylamine fungicide, belonging to the most widely known member of the amide group. This task is aimed to scrutinize binding region and spatial structural change of principal vector human serum albumin (HSA) complex with (R)-/(S)-metalaxyl by exploiting molecular modeling, steady-state and time-resolved fluorescence, and circular dichroism (CD) approaches. According to molecular modeling, (R)-metalaxyl is situated within subdomains IIA and IIIA and the affinity of site I with (R)-metalaxyl is greater than site II, whereas (S)-metalaxyl is only located at subdomain IIA and the affinity of (S)-metalaxyl with site I is superior compared with that with (R)-metalaxyl. This coincides with the competitive ligand binding, guanidine hydrochloride-induced unfolding of protein, and hydrophobic 8-anilino-1-naphthalenesulfonic acid experiments; the acting forces between (R)-/(S)-metalaxyl and HSA are hydrophobic, π-π interactions, and hydrogen bonds, as derived from molecular modeling. Fluorescence emission manifested that the complex of (R)-/(S)-metalaxyl to HSA is the formation of adduct with an affinity of 10(4) M(-1), which corroborates the time-resolved fluorescence that the static type was operated. Furthermore, the changes of far-UV CD spectra evidence the polypeptide chain of HSA partially unfolded after conjugation with (R)-/(S)-metalaxyl. Through this work, we envisage that it can offer central clues on the biodistribution, absorption, and bioaccumulation of (R)-/(S)-metalaxyl.

Human serum albumin stability and toxicity of anthraquinone dye alizarin complexone: an albumin-dye model.

The complexation between the primary vector of ligands in blood plasma, human serum albumin (HSA) and a toxic anthraquinone dye alizarin complexone, was unmasked by means of circular dichroism (CD), molecular modeling, steady state and time-resolved fluorescence, and UV/vis absorption measurements. The structural investigation of the complexed HSA through far-UV CD, three-dimensional and synchronous fluorescence shown the polypeptide chain of HSA partially destabilizing with a reduction of α-helix upon conjugation. From molecular modeling and competitive ligand binding results, Sudlow's site I, which was the same as that of warfarin-azapropazone site, was appointed to retain high-affinity for alizarin complexone. Moreover, steady state fluorescence displayed that static type and Förster energy transfer is the operational mechanism for the vanish in the tryptophan (Trp)-214 fluorescence, this corroborates time-resolved fluorescence that HSA-alizarin complexone adduct formation has an affinity of 10(5) M(-1), and the driving forces were found to be chiefly π-π, hydrophobic, and hydrogen bonds, associated with an exothermic free energy change. These data should be utilized to illustrate the mechanism by which the toxicological action of anthraquinone dyes is mitigated by transporter HSA.

Potential toxicity and affinity of triphenylmethane dye malachite green to lysozyme.

Malachite green is a triphenylmethane dye that is used extensively in many industrial and aquacultural processes, generating environmental concerns and health problems to human being. In this contribution, the complexation between lysozyme and malachite green was verified by means of computer-aided molecular modeling, steady state and time-resolved fluorescence, and circular dichroism (CD) approaches. The precise binding patch of malachite green in lysozyme has been identified from molecular modeling and ANS displacement, Trp-62, Trp-63, and Trp-108 residues of lysozyme were earmarked to possess high-affinity for this dye, the principal forces in the lysozyme-malachite green adduct are hydrophobic and π-π interactions. Steady state fluorescence proclaimed the complex of malachite green with lysozyme yields quenching through static type, which substantiates time-resolved fluorescence measurements that lysozyme-malachite green conjugation formation has an affinity of 10(3)M(-1). Moreover, via molecular modeling and also CD data, we can safely arrive at a conclusion that the polypeptide chain of lysozyme partially destabilized upon complexation with malachite green. The data emerged here will help to further understand the toxicological action of malachite green in human body.

Gender Differences in Psychiatric Symptoms and the Social Functioning of 610 Patients with Schizophrenia in Urban China: A 10-Year Follow-Up Study.

Purpose: To explore the different outcomes between male and female patients with schizophrenia after long-term follow-up. Patients and Methods: Schizophrenia patients were participants in our study. First, two senior psychiatrists collected data on the demographic characteristics and clinical symptoms of patients from the Hospital Information System between February 2009 and January 2010. Second, two other senior psychiatrists called the patients and their guardians between February 2019 and January 2020 to get general information on the patients and assess their psychiatric symptoms and social functioning using the Positive and Negative Syndrome Scale (PANSS) and the Personal and Social Performance (PSP) scale. Results: Of the 610 participants, the 306 female participants were younger (48.32 ± 12.99 vs 49.84 ± 12.60) and had received more education (8.08 ± 3.76 vs 7.94 ±3 0.73). After 10 years, women were found to have more outpatient visits than men (20.86 ± 22.21 vs 16.11 ± 16.87, P < 0.05). However, there was no significant gender difference in number of hospitalizations (3.12 ± 5.34 vs 2.77 ± 5.84, P > 0.05). The PANSS scores were lower for both groups at the 10-year follow-up. Women had significantly lower scores than men after the 10-year period (P < 0.05). With regard to social functioning, there was a significant difference in social functioning between baseline scores and 10-year follow-up scores indicating an improvement in social functioning. PSP scores had significantly increased in women (P < 0.01) but not in men (P > 0.05). Conclusion: Female patients had significantly lower levels of psychiatric symptoms and higher levels of social functioning at 10-year follow-up than male patients. They also reported more outpatient visits, which may have contributed to the gender differences in outcomes. Family members and doctors of patients should urge patients to make regular outpatient visits for better outcomes after hospitalization.

Transcriptome Analysis of Antennal Chemosensory Genes in Curculio Dieckmanni Faust. (Coleoptera: Curculionidae).

The olfactory system plays a key role in regulating insect behaviors, such as locating host plants, spawning sites, and mating partners and avoiding predators. Chemosensory genes are required for olfactory recognition in insects. Curculio dieckmanni Faust. (Coleoptera: Curculionidae) damages hazelnuts and causes severe economic losses. There are no effective control measures, but understanding the olfaction mechanisms of this insect could lead to a new approach for population management. However, the genes that perform chemosensory functions in C. dieckmanni are still unclear. Using high-throughput sequencing, we assembled the antennal transcriptome of C. dieckmanni and annotated the major chemosensory gene families. Of the chemosensory gene families, we found 23 odorant-binding proteins, 15 chemosensory proteins, 2 sensory neuron membrane proteins, 15 odorant receptors, 23 ionotropic receptors, and nine gustatory receptors. Using Blast sequence alignment and phylogenetic analysis, the sequences of these proteins were identified. Male- and female-specific chemosensory genes involved in odorant detection and recognition were validated by qRT-PCR. Among the chemosensory genes, we found significant differences in the expression of CdieOBP8, CdieOBP9, CdieOBP19, CdieOBP20, CdieOBP21, CdieCSP15, CdieOR13, and CdieOR15 between adult male and female C. dieckmanni. A total of 87 expressed chemosensory proteins were found in C. dieckmanni. Investigating these proteins will help reveal the molecular mechanism of odorant recognition in C. dieckmanni and may aid the development of novel control strategies for this species.

A Complete Genome Sequence of the Wood Stem Endophyte Bacillus velezensis BY6 Strain Possessing Plant Growth-Promoting and Antifungal Activities.

An endophytic bacterium Bacillus velezensis BY6 was isolated from the wood stems of healthy Populus davidiana × P. alba var. pyramidalis (PdPap). The BY6 strain can inhibit pathogenic fungus Alternaria alternate in PdPap and promote growth of PdPap seedlings. In the present study, we used the Pacific Biosciences long-read sequencing platform, a single-molecule real-time (SMRT) technology for strain BY6, to perform complete genome sequencing. The genome size was 3,898,273 bp, the number of genes was 4,045, and the average GC content was 47.33%. A complete genome of strain BY6 contained 110 secondary metabolite gene clusters. Nine of the secondary metabolite gene clusters exhibited antifungal activity and promoted growth functions primarily involved in the synthesis of surfactin, bacteriocins, accumulated iron ions, and related antibiotics. Gene clusters provide genetic resources for biotechnology and genetic engineering, and enhance understanding of the relationship between microorganisms and plants.

Genome-Wide Analysis of Major Facilitator Superfamily and Its Expression in Response of Poplar to Fusarium oxysporum.

The major facilitator superfamily (MFS) is one of the largest known membrane transporter families. MFSs are involved in many essential functions, but studies on the MFS family in poplar have not yet been reported. Here, we identified 41 MFS genes from Populus trichocarpa (PtrMFSs). We built a phylogenetic tree, which clearly divided members of PtrMFS into six groups with specific gene structures and protein motifs/domains. The promoter regions contain various cis-acting elements involved in stress and hormone responsiveness. Genes derived from segmental duplication events are unevenly distributed in 17 poplar chromosomes. Collinearity analysis showed that PtrMFS genes are conserved and homologous to corresponding genes from four other species. Transcriptome data indicated that 40 poplar MFS genes were differentially expressed when treated with Fusarium oxysporum. Co-expression networks and gene function annotations of MFS genes showed that MFS genes tightly co-regulated and closely related in function of transmembrane transport. Taken together, we systematically analyzed structure and function of genes and proteins in the PtrMFS family. Evidence indicated that poplar MFS genes play key roles in plant development and response to a biological stressor.

Transcriptome Analysis Reveals the Important Role of WRKY28 in Fusarium oxysporum Resistance.

Root rot of Populus davidiana × P. alba var. pyramidalis Louche (Pdpap) is caused by Fusarium oxysporum. We used RNA sequencing to study the molecular mechanisms and response pattern of Pdpap infected by F. oxysporum CFCC86068. We cloned the PdpapWRKY28 transcription factor gene and transformed the recombinant vector pBI121-PdpapWRKY28 into Pdpap. The resistance function of PdpapWRKY28 was verified using physiological and biochemical methods. By means of RNA sequencing, we detected 1,403 differentially expressed genes (DEGs) that are common in the different treatments by F. oxysporum. Furthermore, we found that overexpression of the PdpapWRKY28 gene may significantly improve the resistance of Pdpap plants to F. oxysporum. Our research reveals a key role for PdpapWRKY28 in the resistance response of Pdpap to F. oxysporum. Additionally, our results provide a theoretical basis for in-depth research on resistance breeding to combat root rot.

Construction and validation a nomogram to predict overall survival for colorectal signet ring cell carcinoma.

To construct and validate a nomogram to predict the overall survival (OS) of colorectal signet ring cell carcinoma (SRCC). The potentially eligible cases were obtained against the SEER database from 2004 to 2015. Log-rank test and Cox analysis were conducted to identify the independent prognostic factors for predicting OS. The identified prognostic factors were later integrated for the construction of an OS prediction nomogram. Altogether 2904 eligible cases were identified, and the median survival time was 18 (range: 0-155) months. As suggested by multivariate analysis, age, primary site, grade, tumor size, T stage, N stage, M stage, surgery, lymph node dissection and chemotherapy were identified as the independent factors for predicting OS. Afterwards, the above variables were incorporated into the nomogram. The C-index indicated better discriminatory ability of the nomogram than AJCC 8th TNM staging and SEER summary stage systems (both P < 0.001). Calibration plots further showed good consistency between the nomogram prediction and actual observation. The time independent area under the curves (tAUCs) for 3-year and 5-year OS in nomogram were larger than AJCC and SEER summary stage system. The constructed nomogram could potentially predict the survival of colorectal SRCC individuals.

Marital status and survival of patients with colorectal signet ring cell carcinoma: a population-based study.

The prognostic role of marital status on colorectal signet ring cell carcinoma (SRCC) has not been studied. In this study, the correlation of marital status with prognosis of colorectal SRCC was analyzed. Eligible subjects were extracted from the Surveillance, Epidemiology, and End Results (SEER) dataset from 2004 to 2015, followed by comparison of cancer-specific survival (CSS) and overall survival (OS) between married and unmarried group. 3152 patients were identified including 1777 married patients (56.38%). Married populations tended to be more patients aged < 65, male, receiving chemotherapy, and less black race and large tumor size compared to unmarried group (all P < 0.05).Moreover, 5-year CSS (30.04% vs. 28.19%, P = 0.0013) and OS rates (26.68% vs. 22.94%, P < 0.0001) were superior in married population. Multivariate analysis revealed that marital status was an independent favorable prognostic indicator, and married population had better CSS (HR: 0.898; 95% CI: 0.822-0.980; P = 0.016) and OS (HR: 0.898; 95%CI: 0.827-0.975; P = 0.011).In addition, CSS as well as OS were superior in married populations than unmarried ones in most subgroups. Marital status was an independent prognostic factor for survival in patients with colorectal SRCC. Additionally, married patients obtained better survival advantages.

Antioxidant and Antiapoptotic Polyphenols from Green Tea Extract Ameliorate CCl4-Induced Acute Liver Injury in Mice.

OBJECTIVE: To investigate the phenolic composition, antioxidant properties, and hepatoprotective mechanisms of polyphenols from green tea extract (GTP) in carbon tetrachloride (CCl4)-induced acute liver injury mouse model. METHODS: High-performance liquid chromatography was used to analyze the chemical composition of the extract. Antioxidant activity of GTP was assessed by O2∙-, OH∙, DPPH∙, and ferric-reducing antioxidant power (FRAP) assay in vitro. Sixty Kunming mice were divided into 6 groups including control, model, low-, medium-, and high-doses GTP (200, 400, 800 mg/kg) and vitamin E (250 mg/kg) groups, 10 in each group. GTP and vitamin E were administered at a level of abovementioned doses twice per day for 7 days prior to exposure to a single injection of CCl4. Hepatoprotective effects of GTP were evaluated in a CCl4-induced mouse model of acute liver injury, using commercial enzyme linked immunosorbent assay kits, histopathological observation, terminal deoxynucleotidyl transferase-mediated dUTPNick-end labeling (TUNEL) assay and Western blot. RESULTS: GTP contained 98.56 µg gallic acid equivalents per milligram extract total polyphenols, including epicatechingallate, epigallocatechin gallate, epicatechin, and epigallocatechin. Compared with the model group, low-, medium-, or high doses GTP significantly decreased serum levels of alanine aminotransferase and aspartate transaminase (P<0.01). Histopathological observation confirmed that pretreatment of GTP prevented swelling and necrosis in CCl4-exposed hepatocytes. Hepatoprotective effects of low-, medium-, and high-dose GTP were associated with eliminating free radicals and improving superoxide dismutase, catalase, and glutathione peroxidase activity in the liver. Additionally, low-, medium-, and high-dose GTP decreased cell apoptosis in the CCl4-exposed liver (P<0.01). Phosphorylated nuclear factor kappa-B (NF-κB), p53, Bcl-2 associated x protein/B-cell lymphoma/leukemia-2 gene, cytochrome C, and cleaved caspase-3 levels were downregulated compared with the model group (P<0.01). CONCLUSION: GTP achieves hepatoprotective effects by improving hepatic antioxidant status and preventing cell apoptosis through caspase-3-dependent signaling pathways.