The transcriptome analysis of males musk gland in Moschus berezovskii (Artiodactyla: Moschidae)

Synergistic Antibacterial Effect of Phage pB3074 in Combination with Antibiotics Targeting Cell Wall against Multidrug-Resistant Acinetobacter baumannii In Vitro and Ex Vivo

Synergistic effects of phages in combination with antibiotics have received increasing attention. In this present study, we isolated a new phage pB3074 against clinically isolated multidrug-resistant Acinetobacter baumannii. Phage pB3074 combined with cell wall-targeting antibiotics could produce synergistic antibacterial effect in vitro bactericidal activities. Further research indicates that the bacteriophage dose is critical to synergistic antimicrobial effect of phage and antibiotic combination. Cefotaxime and meropenem were selected as the representative cell wall-targeting antibiotics for further synergistic antibacterial study. Results illustrated that phage pB3074 and cefotaxime or meropenem combination was very effective for the removal of mature biofilm and inhibition of biofilm formation. In a pig skin explant model, results also showed that phage pB3074 and cefotaxime or meropenem combination was very effective for the treatment of wound infection ex vivo. Subsequent studies showed that some extent recovery of drug sensitivity to cell wall-targeting antibiotics might be vital mechanism of synergistic antibacterial effect between bacteriophage pB3074 and these antibiotics. The existence of antibiotics could promote phage adsorption and proliferation, which might also be potential mechanism for synergistic antibacterial activities and have been observed in cefotaxime and meropenem application. In summary, results in the current study demonstrated that phage pB3074 has the potential to be developed as an antibacterial agent and combined application of phages and antibiotics might be a new choice for the treatment of current multidrug-resistant bacterial infections. IMPORTANCE Combined application of phages and antibiotics cannot only effectively inhibit the appearance of phage-resistant bacteria, but also reduce the effective use concentration of antibiotics, and even make some bacteria regain sensitivity to some resistant antibiotics. Therefore, phage-antibiotic combination (PAC) could improve the antibacterial activity of individual drug, providing a new choice for clinical treatment of multidrug-resistant bacterial infections.

Differential expression profiles of microRNAs in musk gland of unmated and mated forest musk deer (Moschus berezovskii)

Background

The formation of musk is a complex biophysical and biochemical process that change with the rut of male forest musk deer. We have reported that the mating status of male forest musk deer might result to the variations of chemical composition and microbiota of musk and its yields. Critical roles for microRNAs (miRNAs) of multi-tissues were profiled in our previous study; however, the role for miRNAs of the musk gland remains unclear in this species.

Methods

In this study, we used Illumina deep sequencing technology to sequence the small RNA transcriptome of unmated male (UM) and mated male (UM) of Chinese forest musk deer.

Results

We identified 1,652 known miRNAs and 45 novel miRNAs, of which there were 174 differentially expressed miRNAs between UM and MM. chi-miR-21-5p, ipu-miR-99b and bta-miR-26a were up-regulated in UM among the 10 most differentially expressed miRNAs. Functional enrichment of the target genes showed that monosaccharide biosynthetic process, protein targeting, cellular protein catabolic process enriched higher in MM. Meanwhile, structural molecule activity, secretion by cell, regulated exocytosis and circulatory system process enriched more in UM, hinting that the formation of musk in UM was mediated by target genes related to exocytosis. The miRNA-mRNA pairs such as miR-21: CHD7, miR143: HSD17B7, miR-141/200a: Noc2 might involve in musk gland development and musk secretion, which need to be verified in future study.

Characteristics of steroidogenesis-related factors in the musk gland of Chinese forest musk deer (Moschus berezovskii)

Musk secreted by Chinese forest musk deer (FMD; Moschus berezovskii) is a highly valuable ingredient in the fields of perfumery and medicine, and the main factor affecting the production of musk is the androgen level of male FMD. To clarify whether the musk gland of FMD can synthesize androgen, we compared and analyzed the expression patterns of steroid hormone biosynthesis-related genes in the musk gland and testis of FMD by RNA-seq and RT-qPCR. We obtained 33,308 and 38,602 unigenes from the musk gland and testis, respectively, and 26,780 co-expressed unigenes. Analysis of co-expressed genes revealed that 12,647 genes were annotated to 11,484 Gene Ontology terms and 10,941 genes were annotated to 6120 pathways, including several pathways important in metabolic and synthetic activity. Next, 21 steroid hormone synthesis-related genes were screened from the transcriptome of the musk gland of 4-month-old FMD. The expression levels of three key genes of steroid hormone biosynthesis (CYP11A1, CYP17A1, and HSD3B) in the musk gland differed from their expression levels in the testis based on RT-qPCR. Furthermore, immunohistochemistry indicated that CYP11A1, CYP17A1, and HSD3B were localized in the glandular tubular columnar cells of the musk gland. These results suggested that the musk gland of male FMD has the potential to locally synthesize steroid hormone and thus plays a critically important role in musk secretion.

Effect of probiotics on diversity and function of gut microbiota in Moschus berezovskii

The forest musk deer, Moschus berezovskii, is a nationally protected species of economic importance in China. However, in captive breeding programmes, they usually die as a result of diarrhoea. In this study, six M. berezovskii were randomly selected and divided into two groups: probiotics group (n = 3) and placebo (control) group (n = 3). The two groups were fed a basal diet that included 2 g probiotics (probiotic group) or 2 g whey powder (placebo group) for 30 days. Faecal samples were collected at day 0, 15 and 30 and evaluated for microbial diversity, species richness and metabolic function. Probiotic intervention significantly improved gut health in M. berezovskii by changing the overall community structure of the gut microbiota. Intake of probiotics reduced the relative abundance of pathogenic bacteria such as Escherichia coli and Citrobacter freundii in the intestinal flora and increased the relative abundance of beneficial Bifidobacterium species and other lactic acid bacteria. At the same time, gut microbiota in the probiotics group were involved in regulating degradation of phenylacetic acid and in dTDP-L-rhamnose synthesis; these processes have the potential to enhance immunity in M. berezovskii. This preliminary study revealed the beneficial effects of probiotics on the gut microbiota of M. berezovskii, which the potential to significantly improve the health, wellbeing and economic value of M. berezovskii.