LncRNA- and circRNA-associated competing endogenous RNA (ceRNA) networks in leukocytes in traditional Chinese medicine (TCM)-defined Pi-qi-deficiency syndrome and Pi-wei damp-heat syndrome resulting from chronic atrophic gastritis
Authors: You Leiming , Wang Wei , Li Kunyu , Sang Xiaopu , Li Ting’an , Zhang Shen , Gao Xinhui , Wu Jiarui , Huang Guangrui , Wang Ting , Xu Anlong 
Published: October 2021

Abstract
Background

To investigate lncRNA/circRNA-associated competing endogenous RNA (ceRNA)-gene regulation underlying leukocyte functions and characteristics, especially the potential ceRNA biomarkers, implicated in traditional Chinese medicine (TCM)-defined Pi-qi-deficiency syndrome (PQDS) and Pi-wei damp-heat syndrome (PDHS) resulting from chronic atrophic gastritis (CAG).
Methods

Based on RNA-sequencing approach, comparing with healthy control population, we identified the PDHS- or PQDS-specific lncRNAs/circRNAs in leukocytes, especially the Zheng (syndrome)-specific ceRNAs and their corresponding ceRNA regulatory networks, further decoding their potential functions and pathways.
Results

Despite being the TCM-defined Zhengs resulting from the same disease of CAG, the Zheng-specific lncRNAs/circRNAs in leukocytes were not same in PQDS and PDHS. There were the Zheng-specific lncRNA/circRNA-associated ceRNAs identified in the leukocytes, and their corresponding ceRNA regulatory networks were generated, including the ceRNA-gene binary relationship networks and the miRNA-centered ceRNA-miRNA-gene triple relationship networks. In the generated Zheng-specific ceRNA networks, the PQDS-specific ceRNA-governed genes in leukocytes, keeping more complex interactions with each other, were enriched in pathways related to MAPK signaling, receptor tyrosine kinases signaling as well as complement and coagulation cascades. Notably, the enriched pathways associated with adherens junction, focal adhesion, ECM-receptor interaction, ECM-organization and cell surface interactions, were implicated in cell-to-cell adhesion/junction and communication, probably contributing to the characteristics and functions of leukocytes. The PDHS-specific ceRNA-regulated genes, seemed to have no more interactions with each other, were enriched in the biological processes related to regulation of cell morphogenesis, neutrophil activation and degranulation, and lymphocyte mediated immunity such as B-cell receptor signaling, complement and coagulation cascades, and regulation of NK/T-cell mediated cytotoxicity. Importantly, the five exosome-encapsuled ceRNAs, containing ZFAS1 (NR_036658.2), AL353719.1 (ENST00000566847), LOH12CR2 (NR_024061.1) and two new lncRNAs (TCONS_00038035 and TCONS_00027600), particularly higher expression in the leukocytes in PQDS rather than PDHS, could be the potential ceRNA biomarkers for differentiation of the TCM-defined PQDS and PDHS among CAG patients.
Conclusions

These results may provide new insights into the characteristic and functional changes of leukocytes in the two TCM Zhengs, especially the Zheng-specific ceRNA-mediated gene regulation underlying leukocyte characteristics and functions, with potential leukocyte biomarkers for future application in integrative medicine.