Therapeutic mechanism of steaming umbilical cord therapy with Chinese herbal medicine on a rat model of IBS-D via the PAR-2/TRVP1 pathway.

OBJECTIVE: This study aimed to investigate the PAR-2/TRVP1-based mechanism of steaming umbilical cord therapy with Chinese Herbal Medicine (SUCT-CHM) in IBS-D rat models. METHODS: Sixty-two IBS-D modeled rats were established, and were randomly assigned to the control group (n = 31) and the experimental group (n = 31). The model group did not receive intervention measures, and the experimental group was treated with SUCT-CHM. After 14 days of intervention, the two groups of rats were compared in terms of body weight, gastrointestinal function, Bristol stool score, wet/dry weight ratio of rat stool, and abdominal withdrawal reflex scores. The transient receptor potential vanilloid receptor 1 (TRPV1), protease-activated receptors-2 (PAR-2), calcitonin gene related peptide (CGRP) and Substance P (SP) protein expression were detected using ELISA. RESULTS: After 14 d of intervention, compared to the control group, the rats in the experimental group showed a significant increase in body mass indexes (P < 0.05); decreased Bristol stool scores (P < 0.05); less stagnation of the intestinal contents and greater intestine propulsion rate (P < 0.05), lower wet/dry weight ratio of rat stool (P < 0.05), abdominal withdrawal reflex scores (P < 0.05) as well as PAR-2, TRVP1, CGRP and SP expression levels (P < 0.05). CONCLUSION: SUCT-CHM was effective in treating IBS-D in rats. It improved gastrointestinal function and reduced visceral hypersensitivity in rats possibly via the PAR-2/TRVP1 pathway.

Two New Polyphenol Oxidase Genes of Tea Plant (Camellia sinensis) Respond Differentially to the Regurgitant of Tea Geometrid, Ectropis obliqua.

Polyphenol oxidases (PPOs) have been reported to play an important role in protecting plants from attacks by herbivores. Though PPO genes in other plants have been extensively studied, research on PPO genes in the tea plant (Camellia sinensis) is lacking. In particular, which members of the PPO gene family elicit the defense response of the tea plant are as yet unknown. Here, two new PPO genes, CsPPO1 and CsPPO2, both of which had high identity with PPOs from other plants, were obtained from tea leaves. The full length of CsPPO1 contained an open reading frame (ORF) of 1740 bp that encoded a protein of 579 amino acids, while CsPPO2 contained an ORF of 1788 bp that encoded a protein of 595 amino acids. The deduced CsPPO1 and CsPPO2 proteins had calculated molecular masses of 64.6 and 65.9 kDa; the isoelectric points were 6.94 and 6.48, respectively. The expression products of recombinant CsPPO1 and CsPPO2 in Escherichia coli were about 91 and 92 kDa, respectively, but the recombinant proteins existed in the form of an inclusion body. Whereas CsPPO1 is highly expressed in stems, CsPPO2 is highly expressed in roots. Further results showed that the expression of CsPPO1 and CsPPO2 was wound- and Ectropis obliqua-induced, and that regurgitant, unlike treatment with wounding plus deionized water, significantly upregulated the transcriptional expression of CsPPO2 but not of CsPPO1. The difference between regurgitant and wounding indicates that CsPPO2 may play a more meaningful defensive role against E. obliqua than CsPPO1. Meanwhile, we found the active component(s) of the regurgitant elicited by the expression of CsPPO may contain small molecules (under 3-kDa molecular weight). These conclusions advance the understanding of the biological function of two new PPO genes and show that one of these, CsPPO2, may be a promising gene for engineering tea plants that are resistant to E. obliqua.

Transcriptomic analysis between self- and cross-pollinated pistils of tea plants (Camellia sinensis).

BACKGROUND: Self-incompatibility (SI) is a major barrier that obstructs the breeding process in most horticultural plants including tea plants (Camellia sinensis). The aim of this study was to elucidate the molecular mechanism of SI in tea plants through a high throughput transcriptome analysis. RESULTS: In this study, the transcriptomes of self- and cross-pollinated pistils of two tea cultivars 'Fudingdabai' and 'Yulv' were compared to elucidate the SI mechanism of tea plants. In addition, the ion components and pollen tube growth in self- and cross-pollinated pistils were investigated. Our results revealed that both cultivars had similar pollen activities and cross-pollination could promote the pollen tube growth. In tea pistils, the highest ion content was potassium (K+), followed by calcium (Ca2+), magnesium (Mg2+) and phosphorus (P5+). Ca2+ content increased after self-pollination but decreased after cross-pollination, while K+ showed reverse trend with Ca2+. A total of 990 and 3 common differentially expressed genes (DEGs) were identified in un-pollinated vs. pollinated pistils and self- vs. cross-pollinated groups after 48 h, respectively. Function annotation indicated that three genes encoding UDP-glycosyltransferase 74B1 (UGT74B1), Mitochondrial calcium uniporter protein 2 (MCU2) and G-type lectin S-receptor-like serine/threonine-protein kinase (G-type RLK) might play important roles during SI process in tea plants. CONCLUSION: Ca2+ and K+ are important signal for SI in tea plants, and three genes including UGT74B1, MCU2 and G-type RLK play essential roles during SI signal transduction.