Fecal microbiota transplantation mitigates bone loss by improving gut microbiome composition and gut barrier function in aged rats
Background Gut microbiota (GM) dysbiosis is closely related to bone loss and the occurrence of osteoporosis in animals and human. However, little is known about the effect and the mechanisms of fecal microbiota transplantation (FMT) on bone in the treatment of senile osteoporosis. Methods Aged female rats were randomly divided into the FMT group and the control group. 3-month-old female rats were used as fecal donors. The rats were sacrificed at 12 and 24 weeks following transplantation and the serum, intestine, bone, and feces were collected for subsequent analyses. Results The bone turnover markers of osteocalcin, procollagen type 1 N-terminal propeptide (P1NP), and carboxy-terminal peptide (CTX) decreased significantly at 12 and 24 weeks following FMT (P < 0.05). At 12 weeks following transplantation, histomorphometric parameters including the bone volume (BV), trabecular bone volume fraction (BV/TV), trabecular number (Tb.N), and trabecular thickness (Tb.Th) of the FMT group were comparable to the control group. However, at 24 weeks following transplantation, these parameters of the FMT group were significantly higher than those of the control group (P < 0.05). Besides, the GM aggregated at 12 and 24 weeks following FMT, and the ecological distance was close between the rats in the FMT group and the donor rats. Alpha diversity, shown by the Shannon index and Simpson index, and the Firmicutes/Bacteroidetes ratio decreased significantly after FMT at 24 weeks. Furthermore, FMT restored the GM composition in aged rats at the phylum and family level, and the intestinal microbiota of the aged rats was similar to that of the donor rats. Correlation network analysis indirectly suggested the causality of FMT on alleviating osteoporosis. FMT improved the intestinal structure and up-regulated the expression of tight junction proteins of occludin, claudin, and ZO-1, which might be associated with the protective effects of FMT on bone. Conclusions GM transplanted from young rats alleviated bone loss in aged rats with senile osteoporosis by improving gut microbiome composition and intestinal barrier function. These data might provide a scientific basis for future clinical treatment of osteoporosis through FMT.
Ma et al. (2021) Fecal microbiota transplantation mitigates bone loss by improving gut microbiome composition and gut barrier function in aged rats. PeerJ 9:e12293 https://doi.org/10.7717/peerj.12293
Genome-wide identification and expression analysis of auxin response factors in peanut (Arachis hypogaea L.)
Auxin response factors (ARFs) are transcription factors that regulate the expression of auxin response genes, and have important functions in plant growth and development. In this study, available genome data for peanut (Arachis hypogaea L.) were used to identify AhARF genes. In total, 61 AhARFs and 23 AtARFs were divided into six groups (I–VI). Molecular structural analysis revealed that the protein members of AhARF contain at least two domains, the B3 domain and the Auxin-resp domain, and that some have a C-terminal dimerisation domain. Screening of the transcriptome data of 22 tissues of A. hypogaea cv. Tifrunner in a public database showed high expression levels of AhARF2 and AhARF6. AhARF6 was expressed more highly in the stem and branch than in the root and leaf of the wild species Arachis monticola (A. mon) and cultivated species H103. After treatment with exogenous auxin (NAA), the expression of AhARF6 was inhibited, and this inhibition was greater in A. mon than in H103. The transcriptome map revealed that the expression of AhARF6 was higher in the larger pods of H8107 and ZP06 than in the medium pods of H103 and small pods of A. mon. Moreover, AhARF6-5 was proven to be localised in the nucleus, consistent with the location of AtARF6. These results suggest that AhARF6 may play an important role in pod development in peanut.
Li et al. (2021) Genome-wide identification and expression analysis of auxin response factors in peanut (Arachis hypogaea L.). PeerJ 9:e12319 https://doi.org/10.7717/peerj.12319
Factors related to job burnout among older nurses in Guizhou province, China
Background The nursing workforce shortage has long been a global concern, and with the aging of nurses, this problem has become more prominent. Nursing is recognized as a high-stress occupation, and nurses experience high levels of job burnout, which reduces their professional identity. Older nurses are an indispensable talent force for nursing teams and are extremely important for the stability of nursing teams and improvement in nursing quality. Exploring the mental health and influencing factors of older nurses is very beneficial for the stability and development of nurse teams and patients’ clinical outcomes. Purpose This study aimed to investigate the level of job burnout and its influencing factors among older nurses in Guizhou Province, China and confirm the correlations among job burnout, professional identity and stress level. Methods From July to August 2019, 520 registered nurses aged over 40 years in Guizhou Province, China were surveyed through the Questionnaire Star platform. The questionnaire contained the following four parts: a general information questionnaire, the Maslach Burnout Inventory (MBI), a professional identity scale, and a job stressors scale. Results The results showed that the job burnout score of the 520 older nurses was 55.44 ± 18.62, which was moderate. The level of job burnout was positively correlated with the level of nurse stress and negatively correlated with the level of professional identity, which was influenced by various personal and social factors. Conclusions This study not only revealed that job burnout was still at a moderate level, but also revealed its current status and influencing factors among older nurses in China.
Jiang et al. (2021) Factors related to job burnout among older nurses in Guizhou province, China. PeerJ 9:e12333 https://doi.org/10.7717/peerj.12333
Sexual and psychological health of couples with azoospermia in the context of the COVID-19 pandemic
Background To date, there have been no reports on the sexual and psychological health of patients with azoospermia during the coronavirus disease 2019 (COVID-19) pandemic. Previous studies on the sexual health of couples with azoospermia are limited and are especially lacking in data on the wives of azoospermic men. Methods We conducted a case–control cross-sectional study between 1 July 2020 and 20 December 2020. In total, 100 couples with azoospermia comprised the experimental group and 100 couples with normozoospermia comprised the control group. The couples’ sexual health was measured using standardised sexual function questionnaires (male: International Index of Erectile Function-15 [IIEF-15] and Premature Ejaculation Diagnostic Tool [PEDT]; female: Female Sexual Function Index [FSFI]) and a self-designed questionnaire to evaluate changes in sexual behaviours (sexual satisfaction, desire, frequency of sexual activity, masturbation, and pornography use) during lockdown. The couples’ psychological health was measured using the 7-item Generalized Anxiety Disorder (GAD-7) scale and 9-item Patient Health Questionnaire (PHQ-9). The Actor–Partner Interdependence Model (APIM) was used to analyse the associations between sexual health and psychological health. Results The IIEF-15 scores (53.07 ± 11.11 vs. 57.52 ± 8.57, t = − 3.17, p = 0.00) were lower and the PEDT scores (6.58 ± 3.13 vs. 5.17 ± 2.22, t = 3.67, p = 0.00) and incidence of premature ejaculation (χ2 = 14.73, p = 0.00) were higher for men with azoospermia than for men with normozoospermia. Compared with those of wives of men with normozoospermia, the total FSFI scores (25.12 ± 5.56 vs. 26.75 ± 4.82, t = − 2.22, p = 0.03) of wives of men with azoospermia were lower. The chi-square test showed that the perceived changes in sexual satisfaction (χ2 = 7.22, p = 0.03), frequency of masturbation (χ2 = 21.96, p = 0.00), and pornography use (χ2 = 10.90, p = 0.01) were significantly different between the female groups with azoospermia and normozoospermia, but there were no significant changes in sexual behaviour between the male groups. The GAD-7 (men: 7.18 ± 5.56 vs. 5.68 ± 4.58, p = 0.04; women: 6.65 ± 5.06 vs. 5.10 ± 3.29, p = 0.01) and PHQ-9 scores (men: 10.21 ± 6.37 vs. 7.49 ± 6.10, p = 0.00; women: 8.81 ± 6.50 vs. 6.98 ± 4.43, p = 0.02) were significantly higher for couples with azoospermia than for couples with normozoospermia. The APIM showed that for couples with azoospermia, sexual function negatively correlated with their own anxiety (men: β = −0.22, p = 0.00; women: β = −0.38, p = 0.00) and depression symptoms (men: β = −0.21, p = 0.00; women: β = −0.57, p = 0.00) but not with their partner’s anxiety and depression symptoms (p > 0.05). Conclusions Couples with azoospermia had a lower quality of sexual function and higher levels of psychological distress than couples with normozoospermia. Their sexual health negatively correlated with psychological distress.
Dong et al. (2021) Sexual and psychological health of couples with azoospermia in the context of the COVID-19 pandemic. PeerJ 9:e12162 https://doi.org/10.7717/peerj.12162
Spinal malformations in a naturally isolated Neotropical fish population
Fish populations that reside in completely isolated freshwater ecosystems are rare worldwide. The Vila Velha State Park (VVSP), located in southern Brazil, is recognized for its arenitic formations called sinkholes (furnas), which are completely isolated. Fish populations within, such as those of Psalidodon aff. fasciatus, often develop vertebral malformations due to this isolation from other conspecifics and other species. In this study, we analyzed geometric morphology in digital radiographs to identify congenital deformations of Psalidodon aff. fasciatus in Furna 2 of VVSP. We found many fish with spinal deformities, including wide variation in the number of caudal vertebrae and corporal deformations related to a flattened body and spinal curvature. Females were more affected than males. We also demonstrated that these deformations reflect inbreeding and an absence of gene flow in the population. In conclusion, isolated populations such as fish species in furnas are potential models for evo-devo research.
Kerniske et al. (2021) Spinal malformations in a naturally isolated Neotropical fish population. PeerJ 9:e12239 https://doi.org/10.7717/peerj.12239
Development of a gene doping detection method to detect overexpressed human follistatin using an adenovirus vector in mice
Background Gene doping is the misuse of genome editing and gene therapy technologies for the purpose of manipulating specific genes or gene functions in order to improve athletic performance. However, a non-invasive detection method for gene doping using recombinant adenoviral (rAdV) vectors containing human follistatin (hFST) genes (rAdV<hFST>) has not yet been developed. Therefore, the aim of this study was to develop a method to detect gene doping using rAdV<hFST>. Methods First, we generated rAdV<hFST> and evaluated the overexpression of the hFST gene, FST protein, and muscle protein synthesis signaling using cell lines. Next, rAdV<hFST> was injected intravenously or intramuscularly into mice, and whole blood was collected, and hFST and cytomegalovirus promoter (CMVp) gene fragments were detected using TaqMan-quantitative polymerase chain reaction (qPCR). Finally, to confirm the specificity of the primers and the TaqMan probes, samples from each experiment were pooled, amplified using TaqMan-qPCR, and sequenced using the Sanger sequencing. Results The expression of hFST and FST proteins and muscle protein synthesis signaling significantly increased in C2C12 cells. In long-term, transgene fragments could be detected until 4 days after intravenous injection and 3 days after intramuscular injection. Finally, the Sanger sequencing confirmed that the primers and TaqMan probe specifically amplified the gene sequence of interest. Conclusions These results indicate the possibility of detecting gene doping using rAdV<hFST> using TaqMan-qPCR in blood samples. This study may contribute to the development of detection methods for gene doping using rAdV<hFST>.
Yanazawa et al. (2021) Development of a gene doping detection method to detect overexpressed human follistatin using an adenovirus vector in mice. PeerJ 9:e12285 https://doi.org/10.7717/peerj.12285
Comparative transcriptome analyses of different Salvia miltiorrhiza varieties during the accumulation of tanshinones
Salvia miltiorrhiza (Labiatae) is an important medicinal plant in traditional Chinese medicine. Tanshinones are one of the main active components of S. miltiorrhiza. It has been found that the intraspecific variation of S. miltiorrhiza is relatively large and the content of tanshinones in its roots of different varieties is also relatively different. To investigate the molecular mechanisms that responsible for the differences among these varieties, the tanshinones content was determined and comparative transcriptomics analysis was carried out during the tanshinones accumulation stage. A total of 52,216 unigenes were obtained from the transcriptome by RNA sequencing among which 23,369 genes were differentially expressed among different varieties, and 2,016 genes including 18 diterpenoid biosynthesis-related genes were differentially expressed during the tanshinones accumulation stage. Functional categorization of the differentially expressed genes (DEGs) among these varieties revealed that the pathway related to photosynthesis, oxidative phosphorylation, secondary metabolite biosynthesis, diterpenoid biosynthesis, terpenoid backbone biosynthesis, sesquiterpenoid and triterpenoid biosynthesis are the most differentially regulated processes in these varieties. The six tanshinone components in these varieties showed different dynamic changes in tanshinone accumulation stage. In addition, combined with the analysis of the dynamic changes, 277 DEGs (including one dehydrogenase, three CYP450 and 24 transcription factors belonging to 12 transcription factor families) related to the accumulation of tanshinones components were obtained. Furthermore, the KEGG pathway enrichment analysis of these 277 DEGs suggested that there might be an interconnection between the primary metabolic processes, signaling processes and the accumulation of tanshinones components. This study expands the vision of intraspecific variation and gene regulation mechanism of secondary metabolite biosynthesis pathways in medicinal plants from the “omics” perspective.
Zhou et al. (2021) Comparative transcriptome analyses of different Salvia miltiorrhiza varieties during the accumulation of tanshinones. PeerJ 9:e12300 https://doi.org/10.7717/peerj.12300
Functional analysis of a dihydroflavonol 4-reductase gene in Ophiorrhiza japonica (OjDFR1) reveals its role in the regulation of anthocyanin
Dihydroflavonol 4-reductase (DFR), a key regulatory enzyme, participated in the biosynthesis of anthocyanins, proanthocyanidins and other flavonoids that essential for plant survival and human health. However, the role of this enzyme in Ophiorrhiza japonica is still unknown. Here, three putative DFR-like genes were firstly isolated from O. japonica. Phylogenetic analysis indicated that OjDFR1 was classified into DFR subgroup, while the rest two were clustered into other NADPH-dependent reductases. Then, functions of the three genes were further characterized. Expression analysis showed that OjDFR1 transcripts had strong correlations with the accumulation pattern of anthocyanin during the flower developmental, whereas other two were not, this suggested the potential roles of OjDFR1 in anthocyanin biosynthesis. Subsequently, all three clones were functionally expressed in Escherichia coli, but confirming that only OjDFR1 encode active DFR proteins that catalyzed the reduction of dihydroflavonols to leucoanthocyanidin. Consistant with the biochemical assay results, overexpressing OjDFR1 in Arabidopsis tt3-1 mutant successfully restored the deficiency of anthocyanin and proanthocyanidin, hinting its function as DFR in planta. Additionally, heterologous expression of OjDFR1 in transgenic tobacco contributed to darker flower color via up-regulating the expressions of endogenous NtANS and NtUFGT, which suggested that OjDFR1 was involved in flower color development. In summary, this study validates the functions of OjDFR1 and expands our understanding of anthocyanin biosynthesis in O. japonica.
Sun et al. (2021) Functional analysis of a dihydroflavonol 4-reductase gene in Ophiorrhiza japonica (OjDFR1) reveals its role in the regulation of anthocyanin. PeerJ 9:e12323 https://doi.org/10.7717/peerj.12323
DNA barcode reference library construction and genetic diversity and structure analysis of Amomum villosum Lour. (Zingiberaceae) populations in Guangdong Province
Background Amomum villosum Lour. is the plant that produces the famous traditional Chinese medicine Amomi Fructus. Frequent habitat destruction seriously threatens A. villosum germplasm resources. Genetic diversity is very important to the optimization of germplasm resources and population protection, but the range of inherited traits within A. villosum is unclear. In this study, we analyzed the genetic diversity and genetic structures of A. villosum populations in Guangdong and constructed a local reference DNA barcode library as a resource for conservation efforts. Methods DNA barcoding and Inter-Simple Sequence Repeat (ISSR) markers were used to investigate the population genetics of A. villosum. Five universal DNA barcodes were amplified and used in the construction of a DNA barcode reference library. Parameters including percentage of polymorphic sites (PPB), number of alleles (Na), effective number of alleles (Ne), Nei’s gene diversity index (H), and Shannon’s polymorphism information index (I) were calculated for the assessment of genetic diversity. Genetic structure was revealed by measuring Nei’s gene differentiation coefficient (Gst), total population genetic diversity (Ht), intra-group genetic diversity (Hs), and gene flow (Nm). Analysis of molecular variance (AMOVA), Mantel tests, unweighted pair-group method with arithmetic mean (UPGMA) dendrogram, and principal co-ordinates (PCoA) analysis were used to elucidate the genetic differentiation and relationship among populations. Results A total of 531 sequences were obtained from the five DNA barcodes with no variable sites from any of the barcode sequences. A total of 66 ISSR bands were generated from A. villosum populations using the selected six ISSR primers; 56 bands, 84.85% for all the seven A. villosum populations were polymorphic. The A. villosum populations showed high genetic diversity (H = 0.3281, I = 0.4895), whereas the gene flow was weak (Nm = 0.6143). Gst (0.4487) and AMOVA analysis indicated that there is obvious genetic differentiation amongA. villosum populations and more genetic variations existed within each population. The genetic relationship of each population was relatively close as the genetic distances were between 0.0844 and 0.3347.
Gong et al. (2021) DNA barcode reference library construction and genetic diversity and structure analysis of Amomum villosum Lour. (Zingiberaceae) populations in Guangdong Province. PeerJ 9:e12325 https://doi.org/10.7717/peerj.12325
Transcriptomic analysis reveals candidate genes for male sterility in Prunus sibirica
Background The phenomenon of male sterility widely occurs in Prunus sibirica and has a serious negative impact on yield. We identified the key stage and cause of male sterility and found differentially expressed genes related to male sterility in Prunus sibirica, and we analyzed the expression pattern of these genes. This work aimed to provide valuable reference and theoretical basis for the study of reproductive development and the mechanisms of male sterility in Prunus sibirica. Method The microstructures of male sterile flower buds and male fertile flower buds were observed by paraffin section. Transcriptome sequencing was used to screen genes related to male sterility in Prunus sibirica. Quantitative real-time PCR analysis was performed to verify the transcriptome data. Results Anther development was divided into the sporogenous cell stage, tetrad stage, microspore stage, and pollen maturity stage. Compared with male fertile flower buds, in the microspore stage, the pollen sac wall tissue in the male sterile flower buds showed no signs of degeneration. In the pollen maturity stage, the tapetum and middle layer were not fully degraded, and anther development stopped. Therefore, the microspore stage was the key stage for anther abortion , and the pollen maturity stage was the post stage for anther abortion. A total of 4,108 differentially expressed genes were identified by transcriptome analysis. Among them, 1,899 were up-regulated, and 2,209 were down-regulated in the transcriptome of male sterile flower buds. We found that “protein kinase activity”, “apoptosis process”, “calcium binding”, “cell death”, “cytochrome c oxidase activity”, “aspartate peptidase activity”, “cysteine peptidase activity” and other biological pathways such as “starch and sucrose metabolism” and “proteasome” were closely related to male sterility in Prunus sibirica. A total of 331 key genes were preliminarily screened. Conclusion The occurrence of male sterility in Prunus sibirica involved many biological processes and metabolic pathways. According to the results of microstructure observations, related physiological indexes determination and transcriptome analysis, we reveal that the occurrence of male sterility in Prunus sibirica may be caused by abnormal metabolic processes such as the release of cytochrome c in the male sterile flower buds, the imbalance of the antioxidant system being destroyed, and the inability of macromolecular substances such as starch to be converted into soluble small molecules at the correct stage of reproductive development, resulting in energy loss. As a result, the tapetum cannot be fully degraded, thereby blocking anther development, which eventually led to the formation of male sterility.
Chen et al. (2021) Transcriptomic analysis reveals candidate genes for male sterility in Prunus sibirica. PeerJ 9:e12349 https://doi.org/10.7717/peerj.12349