Gut microbiota is involved in male reproductive function: a review.

Globally, ~8%-12% of couples confront infertility issues, male-related issues being accountable for 50%. This review focuses on the influence of gut microbiota and their metabolites on the male reproductive system from five perspectives: sperm quality, testicular structure, sex hormones, sexual behavior, and probiotic supplementation. To improve sperm quality, gut microbiota can secrete metabolites by themselves or regulate host metabolites. Endotoxemia is a key factor in testicular structure damage that causes orchitis and disrupts the blood-testis barrier (BTB). In addition, the gut microbiota can regulate sex hormone levels by participating in the synthesis of sex hormone-related enzymes directly and participating in the enterohepatic circulation of sex hormones, and affect the hypothalamic-pituitary-testis (HPT) axis. They can also activate areas of the brain that control sexual arousal and behavior through metabolites. Probiotic supplementation can improve male reproductive function. Therefore, the gut microbiota may affect male reproductive function and behavior; however, further research is needed to better understand the mechanisms underlying microbiota-mediated male infertility.

Evaluation of immunoregulation and immunoprotective efficacy of Glaesserella parasuis histidine kinase QseC.

QseC is a membrane sensor kinase that enables bacteria to perceive autoinducers -3, adrenaline, and norepinephrine to initiate downstream gene transcription. In this study, we found that the QseC protein of Glaesserella parasuis can serve as an effective antigen to activate the host's immune response. Therefore, we investigated the immunogenicity and host protective effect of this protein. ELISA and indirect immunofluorescence results showed that QseC protein can induce high titer levels of humoral immunity in mice and regularly generate specific serum antibodies. We used MTS reagents to detect lymphocyte proliferation levels and found that QseC protein can cause splenic lymphocyte proliferation with memory and specificity. Further immunological analysis of the spleen cell supernatant revealed significant upregulation of levels of IL-1ß, IL-4 and IFN-γ in the QseC + adjuvant group. In the mouse challenge experiment, it was found that QseC + adjuvant can provide effective protection. The results of this study demonstrate that QseC protein provides effective protection in a mouse model and has the potential to serve as a candidate antigen for a novel subunit vaccine for further research.

Gut microbiota affects obesity susceptibility in mice through gut metabolites.

Introduction: It is well-known that different populations and animals, even experimental animals with the same rearing conditions, differ in their susceptibility to obesity. The disparity in gut microbiota could potentially account for the variation in susceptibility to obesity. However, the precise impact of gut microbiota on gut metabolites and its subsequent influence on susceptibility to obesity remains uncertain. Methods: In this study, we established obesity-prone (OP) and obesity-resistant (OR) mouse models by High Fat Diet (HFD). Fecal contents of cecum were examined using 16S rDNA sequencing and untargeted metabolomics. Correlation analysis and MIMOSA2 analysis were used to explore the association between gut microbiota and intestinal metabolites. Results: After a HFD, gut microbiota and gut metabolic profiles were significantly different between OP and OR mice. Gut microbiota after a HFD may lead to changes in eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), a variety of branched fatty acid esters of hydroxy fatty acids (FAHFAs) and a variety of phospholipids to promote obesity. The bacteria g_Akkermansia (Greengene ID: 175696) may contribute to the difference in obesity susceptibility through the synthesis of glycerophosphoryl diester phosphodiesterase (glpQ) to promote choline production and the synthesis of valyl-tRNA synthetase (VARS) which promotes L-Valine degradation. In addition, gut microbiota may affect obesity and obesity susceptibility through histidine metabolism, linoleic acid metabolism and protein digestion and absorption pathways.

Genome analysis of the mpox (formerly monkeypox) virus and characterization of core/variable regions.

Since smallpox was eradicated in 1980, the monkeypox virus (MPXV) has emerged as the most threatening orthopoxvirus in the world. In this study, we conducted a comprehensive analysis of the currently published complete genome sequences of the monkeypox virus. The core/variable regions were identified through core-pan analysis of MPXV. Besides single-nucleotide polymorphisms, our study also revealed that specific genes, multi-copy genes, repeat sequences, and recombination fragments are primarily distributed in the variable region. This result suggests that variable regions are not only more susceptible to single-base mutations, but also to events such as gene loss or gain, as well as recombination. Taken together, our results demonstrate the genomic characteristics of the core/variable regions of MPXV, and contribute to our understanding of the evolution of MPXV.

Comparative genomic analysis of alloherpesviruses: Exploring an available genus/species demarcation proposal and method.

The family Alloherpesviridae contains herpesviruses of fish and amphibians. Due to the significant economic losses to aquaculture that herpesviruses can cause, the primary areas of research interest are concerning their pathogenesis and prevention. Despite alloherpesvirus genomic sequences becoming more widely accessible, methods regarding their genus/species classification are still relatively unexplored. In the present study, the phylogenetic relationships between 40 completely sequenced alloherpesviruses were illustrated by the viral proteomic tree (ViPTree), which was divided into three monophyletic groups, namely Cyprinivirus, Ictalurivirus and Batrachovirus. Additionally, average nucleotide identity (ANI) and average amino acid identity (AAI) analyses were performed across all available sequences and clearly displayed species boundaries with the threshold value of ANI/AAI set at 90%. Subsequently, core-pan analysis uncovered 809 orthogroups and 11 core genes shared by all 40 alloherpesvirus genome sequences. For the former, a 15 percent identity depicts a clear genus boundary; for the latter, 8 of them may be qualified for phylogenetic analysis based on amino acid or nucleic acid sequences after being verified using maximum likelihood (ML) or neighbor-joining (NJ) phylogenetic trees. Finally, although the dot plot analysis was valid for the members within Ictalurivirus, it was unsuccessful for Cyprinivirus and Batrachovirus. Taken together, the comparison of individual methodologies provides a wide range of alternatives for alloherpesviruses classification under various circumstances.

Folium Hibisci Mutabilis extract, a potent autophagy enhancer, exhibits neuroprotective properties in multiple models of neurodegenerative diseases.

BACKGROUND: Protein aggregates are considered key pathological features in neurodegenerative diseases (NDs). The induction of autophagy can effectively promote the clearance of ND-related misfolded proteins. OBJECTIVE: In this study, we aimed to screen natural autophagy enhancers from traditional Chinese medicines (TCMs) presenting potent neuroprotective potential in multiple ND models. METHODS: The autophagy enhancers were broadly screened in our established herbal extract library using the transgenic Caenorhabditis elegans (C. elegans) DA2123 strain. The neuroprotective effects of the identified autophagy enhancers were evaluated in multiple C. elegans ND models by measuring Aß-, Tau-, α-synuclein-, and polyQ40-induced pathologies. In addition, PC-12 cells and 3 × Tg-AD mice were employed to further validate the neuroprotective ability of the identified autophagy enhancers, both in vitro and in vivo. Furthermore, RNAi bacteria and autophagy inhibitors were used to evaluate whether the observed effects of the identified autophagy enhancers were mediated by the autophagy-activated pathway. RESULTS: The ethanol extract of Folium Hibisci Mutabilis (FHME) was found to significantly increase GFP::LGG-1-positive puncta in the DA2123 worms. FHME treatment markedly inhibited Aß, α-synuclein, and polyQ40, as well as prolonging the lifespan and improving the behaviors of C. elegans, while siRNA targeting four key autophagy genes partly abrogated the protective roles of FHME in C. elegans. Additionally, FHME decreased the expression of AD-related proteins and restored cell viability in PC-12 cells, which were canceled by cotreatment with 3-methyladenine (3-MA) or bafilomycin A1 (Baf). Moreover, FHME ameliorated AD-like cognitive impairment and pathology, as well as activating autophagy in 3 × Tg-AD mice. CONCLUSION: FHME was successfully screened from our natural product library as a potent autophagy enhancer that exhibits a neuroprotective effect in multiple ND models across species through the induction of autophagy. These findings offer a new and reliable strategy for screening autophagy inducers, as well as providing evidence that FHME may serve as a possible therapeutic agent for NDs.

Comprehensive analysis of transcriptome and metabolome analysis reveal new targets of Glaesserella parasuis glucose-specific enzyme IIBC (PtsG).

The ptsG (hpIIBCGlc) gene, belonging to the glucose-specific phosphotransferase system, encodes the bacterial glucose-specific enzyme IIBC. In this study, the effects of a deletion of the ptsG gene were investigated by metabolome and transcriptome analyses. At the transcriptional level, we identified 970 differentially expressed genes between ΔptsG and sc1401 (Padj<0.05) and 2072 co-expressed genes. Among these genes, those involved in methane metabolism, amino sugar and nucleotide sugar metabolism, starch and sucrose metabolism, pyruvate metabolism, phosphotransferase system (PTS), biotin metabolism, Two-component system and Terpenoid backbone biosynthesis showed significant changes in the ΔptsG mutant strain. Metabolome analysis revealed that a total of 310 metabolites were identified, including 20 different metabolites (p < 0.05). Among them, 15 metabolites were upregulated and 5 were downregulated in ΔptsG mutant strain. Statistical analysis revealed there were 115 individual metabolites having correlation, of which 89 were positive and 26 negative. These metabolites include amino acids, phosphates, amines, esters, nucleotides, benzoic acid and adenosine, among which amino acids and phosphate metabolites dominate. However, not all of these changes were attributable to changes in mRNA levels and must also be caused by post-transcriptional regulatory processes. The knowledge gained from this lays the foundation for further study on the role of ptsG in the pathogenic process of Glaesserella parasuis (G.parasuis).

Corrigendum: The Microbiota and It's Correlation With Metabolites in the Gut of Mice With Nonalcoholic Fatty Liver Disease.

[This corrects the article DOI: 10.3389/fcimb.2022.870785.].

Comparative genomic analysis reveals new evidence of genus boundary for family Iridoviridae and explores qualified hallmark genes.

Members of the family Iridoviridae (iridovirids) are globally distributed and trigger adverse economic and ecological impacts on aquaculture and wildlife. Iridovirids taxonomy has previously been studied based on a limited number of genomes, but this is not suitable for the current and future virological studies as more iridovirids are emerging. In our study, 57 representative iridovirids genomes were selected from a total of 179 whole genomes available on NCBI. Then 18 core genes were screened out for members of the family Iridoviridae. Average amino acid sequence identity (AAI) analysis indicated that a cut-off value of 70% is more suitable for the current iridovirids genome database than ICTV-defined 50% threshold to better clarify viral genus boundaries. In addition, more subgroups were divided at genus level with the AAI threshold of 70%. This observation was further confirmed by genomic synteny analysis, codon usage preference analysis, genome GC content and length analysis, and phylogenic analysis. According to the pairwise comparison analysis of core genes, 9 hallmark genes were screened out to conduct preliminary identification and investigation at the genus level of iridovirids in a more convenient and economical manner.

ANI analysis of poxvirus genomes reveals its potential application to viral species rank demarcation.

Average nucleotide identity (ANI) is a prominent approach for rapidly classifying archaea and bacteria by recruiting both whole genomic sequences and draft assemblies. To evaluate the feasibility of ANI in virus taxon demarcation, 685 poxviruses were assessed. Prior to the analysis, the fragment length and threshold of the ANI value were optimized as 200 bp and 98 per cent, respectively. After ANI analysis and network visualization, the resulting sixty-one species (ANI species rank) were clustered and largely consistent with the groupings found in National Center for Biotechnology Information Virus [within the International Committee on Taxonomy of Viruses (ICTV) Master Species List]. The species identities of thirty-four other poxviruses (excluded by the ICTV Master Species List) were also identified. Subsequent phylogenetic analysis and Guanine-Cytosine (GC) content comparison done were found to support the ANI analysis. Finally, the BLAST identity of concatenated sequences from previously identified core genes showed 91.8 per cent congruence with ANI analysis at the species rank, thus showing potential as a marker gene for poxviruses classification. Collectively, our results reveal that the ANI analysis may serve as a novel and efficient method for poxviruses demarcation.

The Microbiota and It's Correlation With Metabolites in the Gut of Mice With Nonalcoholic Fatty Liver Disease.

In recent years, nonalcoholic fatty liver disease (NAFLD) has become the most common liver disease in the world. As an important model animal, the characteristics of gut microbiota alteration in mice with NAFLD have been studied but the changes in metabolite abundance in NAFLD mice and how the gut microbiota affects these intestinal metabolites remain unclear. In this experiment, a mouse model for NAFLD was established by a high-fat diet. The use of 16S rDNA technology showed that while there were no significant changes in the alpha diversity in the cecum of NAFLD mice, the beta diversity changed significantly. The abundance of Blautia, Unidentified-Lachnospiraceae, Romboutsia, Faecalibaculum, and Ileibacterium increased significantly in NAFLD mice, while Allobaculum and Enterorhabdus decreased significantly. Amino acids, lipids, bile acids and nucleotide metabolites were among the 167 significantly different metabolites selected. The metabolic pathways of amino acids, SFAs, and bile acids were significantly enhanced, while the metabolic pathways of PUFAs, vitamins, and nucleotides were significantly inhibited. Through correlation and MIMOSA2 analysis, it is suggested that gut microbiota does not affect the changes of lipids and bile acids but can reduce thiamine, pyridoxine, and promote L-phenylalanine and tyramine production. The findings of this study will help us to better understand the relationship between gut microbiota and metabolites in NAFLD.

Interferon-γ enhances the immunosuppressive ability of canine bone marrow-derived mesenchymal stem cells by activating the TLR3-dependent IDO/kynurenine pathway.

BACKGROUND: The immunomodulatory function of mesenchymal stem cells (MSCs) has been considered to be vital for MSC-based therapies. Many works have been devoted to excavate effective strategies for enhancing the immunomodulation effect of MSCs. Nonetheless, canine MSC-mediated immunomodulation is still poorly understood. METHODS AND RESULTS: The inflammatory microenvironment was simulated through the employment of interferon-γ (IFN-γ) in a culture system. Compared with unstimulated cBMSCs, IFN-γ stimulation increased the mRNA levels of Toll-like receptor 3 (TLR3) and indoleamine 2, 3-dioxygenase 1 (IDO-1), and simultaneously enhanced the secretion of immunosuppressive molecules, including interleukin (IL)-10, hepatocyte growth factor (HGF), and kynurenine in cBMSCs. IFN-γ stimulation significantly enhanced the ability of cBMSCs and their supernatant to suppress the proliferation of murine spleen lymphocytes. Lymphocyte subtyping evaluation revealed that cBMSCs and their supernatant diminished the percentage of CD3+CD4+ and CD3+CD8+ lymphocytes compared with the control group, with a decreasing CD4+/CD8+ ratio. Notably, exposure to IFN-γ decreased the CD4+/CD8+ ratio more effectively than unstimulated cells or supernatant. Additionally, IFN-γ-stimulation increased the mRNA levels of the Th1 cytokines TNF-α, and remarkably decreased the mRNA level of the Th2 cytokine IL-4 and IL-10. CONCLUSION: Our findings substantiate that IFN-γ stimulation can enhance the immunomodulatory properties of cBMSCs by promoting TLR3-dependent activation of the IDO/kynurenine pathway, increasing the secretion of immunoregulatory molecules and strengthening interactions with T lymphocytes, which may provide a meaningful strategy for the clinical application of cBMSCs in immune-related diseases.

Impact of intracellular response regulator QseB in quorum sensing regulatory network in a clinical isolate SC1401 of Glaesserella parasuis.

Two component systems (TCS) mediate specific responses to different conditions and/or pressures. In the quorum sensing Glaesserella parasuis (QSE) BC TCS, qseB, as a response regulator, is closely related to the transcriptional regulation of multiple downstream genes. In this study, the effects of qseB gene deletion, which encodes the response regulator of population density sensing in G. parasuis, were studied through biological characteristics and metabolomic analysis. Based on previous research, we further explored the virulence of ΔqseB mutant strains through cell morphology, adhesion and invasion. The ΔqseB mutant and parent strains were sequenced by metabolome and combined with the previous transcriptome sequencing results for joint analysis. This study aims to clarify the regulatory effect of QseB on the virulence of G. parasuis and lay the foundation for revealing the pathogenic mechanism of G. parasuis. We detected 476 different metabolites, of which 30 metabolites (6.3%) had a significant difference in abundance between SC1401 and ΔqseB (p < 0.05). We conducted a comparative analysis of pathway enrichment on the transcriptome and metabolome, and found that the two omics participate in seven metabolic pathways together. The top 10 KEGG pathways with the largest number of genes and metabolites identified in this experiment are ABC transporters, Biosynthesis of secondary metabolites, Cysteine and methionine metabolism, Purine metabolism, Pyrimidine metabolism, Metabolic pathways, and Nicotinate and nicotinamide metabolism. Analysis of metabolome sequencing results showed that differential metabolites were also enriched in metabolic pathways, such as Purine metabolism, cGMP-PKG signaling pathway and cAMP signaling pathway, which were not found in transcriptome sequencing data. The internal coloration of the mutant strain ΔqseB was uneven, and the adhesion and invasion ability of PAM cell lines were significantly reduced. We speculate that QseB may affect the adhesion and invasion ability of Glaesserella parasuis by influencing substance transport and signal transduction.

Deletion of two-component system QseBC weakened virulence of Glaesserella parasuis in a murine acute infection model and adhesion to host cells.

The widespread two-component system (TCS), QseBC, involves vital virulence regulators in Enterobacteriaceae and Pasteurellaceae. Here we studied the function of QseBC in Glaesserella parasuis. A ΔqseBC mutant was constructed using a Glaesserella parasuis serovar 11 clinical strain SC1401 by natural transformation. Immunofluorescence was used to evaluate cellular adhesion, the levels of inflammation and apoptosis. The ability of ΔqseBC and ΔqseC mutant strains to adhere to PAM and MLE-12 cells was significantly reduced. Additionally, by focusing on the clinical signs, H&E, and IFA for inflammation and apoptosis, we found that the ΔqseBC mutant weakened virulence in the murine models. Together, these findings suggest that QseBC plays an important role in the virulence of Glaesserella parasuis.

Landscape of keratinocytes transcriptome alterations in response to Trichophyton mentagrophytes infection.

Dermatophytosis is an intractable superficial fungal infection of keratinized structures, with approximately 20% incidence in humans. Alterations of keratinocytes in the pathogenesis of dermatophytosis at the transcriptome level remain unclear. To understand and characterize such responses, keratinocytes were infected with Trichophyton mentagrophytes. After infection with 1 × 105 conidia/mL T. mentagrophytes for 24 h, the adherence of fungal hyphae to keratinocytes and the damage caused to cell morphology and structure were observed by light microscopy and transmission electron microscopy, respectively. Levels of pro-inflammatory cytokines IL-1α, IL-1ß, TNFα, and IL-8 significantly increased after infection. RNA-seq and bioinformatic analyses revealed that 766 genes were significantly whereas 2207 genes were repressed in the T. mentagrophyte-infected cells. Some of the differentially expressed genes (DEGs) were related to inflammation, immune responses, wound healing, metabolism, and oxidative stress. GO and KEGG pathway enrichment analyses revealed that DEGs and pathways involved in inflammatory response, immune response, and pathogen-induced dysfunction were significantly enriched in the infected cells. Furthermore, gene set enrichment analysis revealed that higher expression gene sets were mainly involved in immune responses, whereas lower expression gene sets were related to cell component organization or biogenesis and transporter activity. Furthermore, protein-protein interaction network and function analyses revealed that JUN, TP53, FOS, MYC, and HSP90AA1 play a key role in immune responses. Overall, our study systematically uncovered the transcriptome-level response of keratinocytes to T. mentagrophyte and provided insights into dermatophytosis treatment.

Characteristics of intestinal microbiota in C57BL/6 mice with non-alcoholic fatty liver induced by high-fat diet.

Introduction: As a representation of the gut microbiota, fecal and cecal samples are most often used in human and animal studies, including in non-alcoholic fatty liver disease (NAFLD) research. However, due to the regional structure and function of intestinal microbiota, whether it is representative to use cecal or fecal contents to study intestinal microbiota in the study of NAFLD remains to be shown. Methods: The NAFLD mouse model was established by high-fat diet induction, and the contents of the jejunum, ileum, cecum, and colon (formed fecal balls) were collected for 16S rRNA gene analysis. Results: Compared with normal mice, the diversity and the relative abundance of major bacteria and functional genes of the ileum, cecum and colon were significantly changed, but not in the jejunum. In NAFLD mice, the variation characteristics of microbiota in the cecum and colon (feces) were similar. However, the variation characteristics of intestinal microbiota in the ileum and large intestine segments (cecum and colon) were quite different. Discussion: Therefore, the study results of cecal and colonic (fecal) microbiota cannot completely represent the results of jejunal and ileal microbiota.

Curcumin Alleviates the Senescence of Canine Bone Marrow Mesenchymal Stem Cells during In Vitro Expansion by Activating the Autophagy Pathway.

Senescence in mesenchymal stem cells (MSCs) not only hinders the application of MSCs in regenerative medicine but is also closely correlated with biological aging and the development of degenerative diseases. In this study, we investigated the anti-aging effects of curcumin (Cur) on canine bone marrow-derived MSCs (cBMSCs), and further elucidated the potential mechanism of action based on the modulation of autophagy. cBMSCs were expanded in vitro with standard procedures to construct a cell model of premature senescence. Our evidence indicates that compared with the third passage of cBMSCs, many typical senescence-associated phenotypes were observed in the sixth passage of cBMSCs. Cur treatment can improve cBMSC survival and retard cBMSC senescence according to observations that Cur (1 µM) treatment can improve the colony-forming unit-fibroblasts (CFU-Fs) efficiency and upregulated the mRNA expression of pluripotent transcription factors (SOX-2 and Nanog), as well as inhibiting the senescence-associated beta-galactosidase (SA-ß-gal) activities and mRNA expression of the senescence-related markers (p16 and p21) and pro-inflammatory molecules (tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6)). Furthermore, Cur (0.1 µM~10 µM) was observed to increase autophagic activity, as identified by upregulation of microtubule-associated protein 1 light chain 3 (LC3), unc51-like autophagy-activating kinase-1 (ULK1), autophagy-related gene (Atg) 7 and Atg12, and the generation of type II of light chain 3 (LC3-II), thereby increasing autophagic vacuoles and acidic vesicular organelles, as well as causing a significant decrease in the p62 protein level. Moreover, the autophagy activator rapamycin (RAP) and Cur were found to partially ameliorate the senescent features of cBMSCs, while the autophagy inhibitor 3-methyladenine (3-MA) was shown to aggravate cBMSCs senescence and Cur treatment was able to restore the suppressed autophagy and counteract 3-MA-induced cBMSC senescence. Hence, our study highlights the important role of Cur-induced autophagy and its effects for ameliorating cBMSC senescence and provides new insight for delaying senescence and improving the therapeutic potential of MSCs.

Genomic analysis of Poxviridae and exploring qualified gene sequences for phylogenetics.

The members of the Poxviridae family are globally distributed all over the world and can cause infectious diseases. Although genome sequences are publicly available for representative isolates of all genera, studies on the criteria for genome-based classification within the Poxviridae family have rarely been reported. In our study, 60 Poxviridae genomes were re-annotated using Prokka. By using BLAST filtration and MCScanX, synteny and similarity of whole genomic amino acid sequences were visualized. According to the analysis pattern, the Chordopoxvirinae and Entomopoxvirinae subfamilies can be subdivided into five and two categories respectively, which is consistent with the phylogenetic tree constructed based on whole genomic amino acid sequences and Poxvirus core genes. Finally, four genes (Early transcription factor, DNA-directed RNA polymerase, RNA polymerase-associated transcription-specificity factor and DNA-dependent RNA polymerase) were selected from Poxvirus core genes by substitution saturation analysis and phylogenetic tree verification. Phylogenetic trees constructed based on single gene and concatenated sequences of the four selected genes showed that the classification of subgroups was consistent with the phylogenetic trees based on genome. Conclusion: a new method based on the similarity of whole genomic amino acid sequences was proposed for Poxviridae taxon demarcation, and the use of the four selected qualified genes will help make phylogenic identification of newly discovered Poxviridae isolates more convenient and accurate.

Protective effect of MitoQ on oxidative stress-mediated senescence of canine bone marrow mesenchymal stem cells via activation of the Nrf2/ARE pathway.

The destruction of biological activity such as senescence and apoptosis caused by oxidative stress could play a pivotal role in the poor therapeutic efficiency of bone marrow mesenchymal stem cells (BMSCs) transplantation. Mitoquinone (MitoQ) has a highly effective mitochondrial antioxidant effect, and has been widely used in many oxidative damage models. This study aimed to investigate the protective effect of MitoQ on the oxidative stress-mediated senescence of canine BMSCs and the underlying mechanism. The senescence of BMSCs was determined by senescence-associated ß-galactosidase staining and quantitative real-time PCR. The expression of p-Nrf2 protein was detected by Western blotting. The results demonstrated that, as BMSCs were expanded in vitro, the senescent phenotype appeared. And the senescence of BMSCs may be caused by oxidative stress, manifested by increasing the level of ROS and decreasing the activity of antioxidant enzymes. Treatment of MitoQ down-regulated the mRNA levels of senescence-related and apoptosis-related genes, but up-regulated the mRNA levels of proliferation-related genes. Meanwhile, ROS generation and senescent activity were reduced in MitoQ-treated BMSCs. Further mechanism studies showed that MitoQ obviously promoted Nrf2 phosphorylation, and also facilitated the translocation of Nrf2 into the nucleus. Moreover, treatment of MitoQ increased the mRNA levels of downstream antioxidant genes and enhanced the activities of superoxide dismutase, catalase, and glutathione peroxidase. Thus, our study revealed that MitoQ, via the Nrf2/ARE signaling pathway, exerts an antioxidant effect as well as potentially delays OS-mediated senescence during BMSCs that were expanded in vitro, which may serve as a novel strategy to optimize the clinical application of BMSCs.