Altered Serum Metabolite Profiling and Relevant Pathway Analysis in Rats Stimulated by Honeybee Venom: New Insight into Allergy to Honeybee Venom

To improve our understanding of the disturbed metabolic pathways and cellular responses triggered by honeybee venom stimulation, we compared the changes in serum metabolites in rats, either stimulated or not by honeybee venom, by performing ¹H nuclear magnetic resonance (NMR) spectrometry-based metabonomics to identify potential biomarkers. In this study, 65 metabolites were structurally confirmed and quantified and the following results were obtained. First, by pattern recognition analysis, 14 metabolites were selected as potential biomarkers 3 h after venom stimulation. Second, metabolic pathway analysis showed that methane metabolism, glyoxylate and dicarboxylate metabolism, tricarboxylic acid cycle, glycine, serine, and threonine metabolism, arginine and proline metabolism were affected. Finally, the time-dependent metabolic modifications indicated that rats could recover without medical treatment 24 h after venom stimulation. In summary, this new insight into the changes in serum metabolites in rats after honeybee venom stimulation has enhanced our understanding of the response of an organism to honeybee venom

A phylogenetic tree showing the relationship of <i>Nosema ceranae</i> isolates.

<p>The partial sequences of 16S ribosomal RNA of <i>N. ceranae</i> from <i>A. cerana</i> collected in different geographic locations of China and from <i>A. mellifera</i> retrieved from GenBank were aligned using ClustalW. The tree was built using the Neighbor-Joining method. The sequence of <i>Encephalitozoon cuniculi</i> was used as an outgroup to root the tree. Numbers at each node represent bootstrap values as percentages of 500 and only bootstrap values greater than 50% are shown.</p

A phylogenetic tree showing the relationship of DWV isolates.

<p>The partial sequences of RNA dependent RNA polymerase (RdRp) of DWV from <i>A. cerana</i> collected from different geographic locations of China and from <i>Apis mellifera</i> retrieved from GenBank were aligned using ClustalW. The sequence of IAPV was used as an outgroup to root the tree. Numbers at each node represent bootstrap values as percentages of 500 and only bootstrap values greater than 50% are shown.</p

A phylogenetic tree showing the relationship of <i>C. bombi</i> isolates.

<p>The partial sequences of 18 S ribosomal RNA of <i>C. bombi</i> from <i>Apis cerana</i> collected from different geographic locations of China and from bumble bee species retrieved from GenBank were aligned using ClustalW. The tree was built using the Neighbor-Joining method. The sequence of <i>Trypanosoma brucei</i> was used as an outgroup to root the tree. Numbers at each node represent bootstrap values as percentages of 500 and only bootstrap values greater than 50% are shown.</p

Synopsis of collection details and prevalence of parasites in <i>A. cerana</i> colonies from 19 provinces in China.

<p>Synopsis of collection details and prevalence of parasites in <i>A. cerana</i> colonies from 19 provinces in China.</p

Pie chart showing the percentage of Bifidobacterium, Neisseriaceae, Pasteurellaceae and Lactobacillus and uncommon bacteria types identified in worker bees.

<p>Pie chart showing the percentage of Bifidobacterium, Neisseriaceae, Pasteurellaceae and Lactobacillus and uncommon bacteria types identified in worker bees.</p

Relative abundance of four bacterial groups between <i>N. ceranae</i>-infected and non-infected <i>A. cerana</i>.

<p>A) Bifidobacterium; B) Lactobacillus, C) Neisseriaceae, and D) Pasteurellaceae. The y-axis depicts fold difference in quantities of each bacterial species between non-infected workers and <i>N. ceranae</i> infected workers. For each bacterial group, the <i>N. ceranae</i> infected workers had relatively lower level of bacterial titer, compared to non-infected bees and therefore was chosen as a calibrator. The concentration of each bacterial group in non-infected bees was compared with calibrator and expressed as n-fold change.</p

Sampling locations in China.

<p>See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0047955#pone-0047955-t002" target="_blank">Table 2</a> for collection details of location.</p

A phylogenetic tree showing the relationship of BQCV isolates.

<p>The partial sequences of 3′ UTR of BQCV from <i>A. cerana</i> collected from different geographic locations of China and from <i>Apis mellifera</i> retrieved from GenBank were aligned using ClustalW. The sequence of IAPV was used as an outgroup to root the tree. Numbers at each node represent bootstrap values as percentages of 500 and only bootstrap values greater than 50% are shown.</p

Primers used for pathogen/parasite and microbiota detection and quantification.

<p>Primers used for pathogen/parasite and microbiota detection and quantification.</p