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Intestinal diseases are one of the main causes of captive giant panda death. Their special dietary habits and gastrointestinal tract structure often lead to intestinal epithelium damage and secondary intestinal infection. The captive giant panda is predisposed to suffer from microbiota dysbiosis due to long-term artificial feeding and antibiotic misuse. However, there are few reported probiotics to treat giant panda enteritis and the associated dysbiosis. This study aims to elucidate the mechanism by which Lactobacillus plantarum G201683 (L. plantarum G83), a promising panda-derived probiotic, exerts a protective effect on intestinal inflammation in the dextran sulfate sodium- (DSS) induced panda microbiota-associated (DPMA) mouse model. The DPMA mouse was generated by antibiotic treatment and 5% DSS drinking water administration to assess the effect of L. plantarum G83 on intestinal inflammation and microbiota in vivo. Our results demonstrated the successful generation of a DPMA mouse model with Enterobacteriaceae enrichment, consistent with the giant panda intestinal microbiota. L. plantarum G83 decreased clinical and histological severity of intestinal inflammation, enhanced intestinal tight junction protein expression (ZO-1, Occludin) and alleviated inflammatory cytokine production (TNF-) in the colon of DPMA mice. The administration of L. plantarum G83 altered the microbiota composition by decreasing pathogen associated taxa such as E. coli and increasing abundance of beneficial bacteria including Bifidobacterium spp. These changes in microbiota composition were associated with an increased concentration of short chain fatty acids (SCFA), reduced NF-κB signaling, and an altered balance of T helper cell subsets. Our findings support L. plantarum G83 as a promising probiotic to treat intestinal inflammation in the giant panda.

Background: The giant panda (Ailuropoda melanoleuca) is an endangered mammalian species native to China. Fewer than 2500 giant pandas are known to exist, many of which are bred in captivity as a means to preserve and repopulate the species. Like other captive mammals, giant pandas acquire age-related cataracts, reducing their quality of life. Recent comparative genome-wide methylation analysis revealed 110 differentially methylated genes associated with cataract formation including six also associated with the formation of age-related cataracts in humans. Results: To investigate the pathological pathway in greater detail, here we used RNA-Seq analysis to investigate the differential expression profiles of genes in three giant pandas with cataracts and three healthy controls. We identified more than 700 differentially expressed genes, 29 of which were selected for further analysis based on their low q-value. We found that many of the genes encoded regulatory and signaling proteins associated with the control of cell growth, migration, differentiation and apoptosis, supporting previous research indicating a key role for apoptosis in cataract formation. Conclusion: The identification of genes involved in the formation of age-related cataracts could facilitate the development of predictive markers, preventative measures and even new therapies to improve the life of captive animals. [ABSTRACT FROM AUTHOR]

Cataracts are a common cause of visual impairment and blindness in mammals. They are usually associated with aging, but approximately one third of cases have a significant genetic component. Cataracts are increasingly prevalent among aging populations of captive giant pandas (Ailuropoda melanoleuca) and it is therefore important to identify genetic determinants that influence the likelihood of cataract development in order to distinguish between congenital and age-related disease. Here we screened for cataract-related genetic effects using a functional candidate gene approach combined with bioinformatics to identify the underlying genetic defect in a giant panda with congenital cataracts. We identified a missense mutation in exon 10 of the HSF4 gene encoding heat shock transcription factor 4. The mutation causes the amino acid substitution R377W in a highly conserved segment of the protein between the isoform-specific and downstream hydrophobic regions. Predictive modeling revealed that the substitution is likely to increase the hydrophobicity of the protein and disrupt interactions with spatially adjacent amino acid side chains. The mutation was not found in 13 unaffected unrelated animals but was found in an unrelated animal also diagnosed with senile congenital cataract. The novel missense mutation in the HSF4 gene therefore provides a potential new genetic determinant that could help to predict the risk of cataracts in giant pandas. [ABSTRACT FROM AUTHOR]

The giant panda (Ailuropoda melanoleuca) is a native species to China. They are rare and endangered and are regarded as the ‘national treasure’ and ‘living fossil’ in China. For the time being, there are only about 2500 giant pandas in the world. Therefore, we still have to do much more efforts to protect the giant pandas. In captive wildlife, the cataract incidence of mammalian always increases with age. Currently, in China, the proportion of elderly giant pandas who suffering from cataract has reached 20%. The eye disorder thus has a strong influence on the physical health and life quality of the elderly giant pandas. To discover the genes associated with the pathogenesis of cataract in the elderly giant panda and achieve the goal of early assessment and diagnosis of cataract in giant pandas during aging, we performed whole genome methylation sequencing in 3 giant pandas with cataract and 3 healthy giant pandas using methylation-dependent restriction-site associated DNA sequencing (MethylRAD). In the present study, we obtained 3.62M reads, on average, for each sample, and identified 116 and 242 differentially methylated genes (DMGs) between the two groups under the context of CCGG and CCWGG on genome, respectively. Further KEGG and GO enrichment analyses determined a total of 110 DMGs that are involved in the biological functions associated with pathogenesis of cataract. Among them, 6 DMGs including EEA1, GARS, SLITRK4, GSTM3, CASP3, and EGLN3 have been linked with cataract in old age. [ABSTRACT FROM AUTHOR]

It has been established beyond doubt that giant panda genome lacks lignin-degrading related enzyme, gastrointestinal microbes may play a vital role in digestion of highly fibrous bamboo diet. However, there is not much information available about the intestinal bacteria composition in captive giant pandas with different ages. In this study, we compared the intestinal bacterial community of 12 captive giant pandas from three different age groups (subadults, adults, and geriatrics) through PCR-denaturing gradient gel electrophoresis (DGGE) and real-time PCR analysis. Results indicated that microbial diversity in the intestine of adults was significantly higher than that of the geriatrics ( p < 0.05), but not significant compared to the subadults ( p > 0.05). The predominant bands in DGGE patterns shared by the twelve pandas were related to Firmicutes and Proteobacteria. Additionally, in comparison to healthy individuals, antibiotic-treated animals showed partial microbial dysbiosis. Real-time PCR analyses confirmed a significantly higher abundance of the Lactobacillus in the fecal microbiota of adults ( p < 0.05), while other bacterial groups and species detected did not significantly differ among the three age groups ( p > 0.05). This study revealed that captive giant pandas with different ages showed different intestinal bacteria composition. [ABSTRACT FROM AUTHOR]

Background: Although repeat sequences constitute about 37% of carnivore genomes, the characteristics and distribution of repeat sequences among carnivore genomes have not been fully investigated. Based on the updated Repbase library, we re-annotated transposable elements (TEs) in four Caniformia genomes (giant panda, polar bear, domestic dog, and domestic ferret) and performed a systematic, genome-wide comparison focusing on the Carnivora-specific SINE family, Can-SINEs. Results: We found the majority of young recently integrated transposable elements are LINEs and SINEs in carnivore genomes. In particular, SINEC1_AMe, SINEC1B_AMe and SINEC_C1 are the top three most abundant Can-SINE subfamilies in the panda and polar bear genomes. Transposition in transposition analysis indicates that SINEC1_AMe and SINEC1B_AMe are the most active subfamilies in the panda and the polar bear genomes. SINEC2A1_CF and SINEC1A_CF subfamilies show a higher retrotransposition activity in the dog genome, and MVB2 subfamily is the most active Can-SINE in the ferret genome. As the giant panda is an endangered icon species, we then focused on the identification of panda specific Can-SINEs. With the panda-associated two-way genome alignments, we identified 250 putative panda-specific (PPS) elements (139 SINEC1_AMes and 111 SINEC1B_AMes) that inserted in the panda genome but were absent at the orthologous regions of the other three genomes. Further investigation of these PPS elements allowed us to identify a new Can-SINE subfamily, the SINEC1_AMe2, which was distinguishable from the current SINEC1_AMe consensus by four non-CpG sites. SINEC1_AMe2 has a high copy number (> 100,000) in the panda and polar bear genomes and the vast majority (> 96%) of the SINEC1_AMe2 elements have divergence rates less than 10% in both genomes. Conclusions: Our results suggest that Can-SINEs show lineage-specific retransposition activity in the four genomes and have an important impact on the genomic landscape of different Caniformia lineages. Combining these observations with results from the COSEG, Network, and target site duplication analysis, we suggest that SINEC1_AMe2 is a young mobile element subfamily and currently active in both the panda and polar bear genomes. [ABSTRACT FROM AUTHOR]