The expression of monoterpene synthase genes and their respective end products are affected by gibberellic acid in Thymus vulgaris

Thymus Vulgaris Inhibit Lung Fibrosis Progression and Oxidative Stress Induced by Bleomycin in Wistar Rats

Idiopathic pulmonary fibrosis (IPF) is a chronic, devastating and fatal disease characterized by aberrant fibroblasts proliferation, oxidative stress and collagen accumulation in the interstitial tissue. We aimed to evaluate in the present study the efficacy of Thymus vulagris extract (TVE) on an experimental model of pulmonary fibrosis induced by bleomycin (BLM). Wistar rats were given a single dose of BLM (4 mg/kg, intratracheal), while TVE (50, 100 and 200 mg/kg, intraperitoneal) was administered 3 days later and continued for 4 weeks. We reveled by HPLC analysis an important amount of phenolic bioactive compounds such as rosmarinic and vanillic acids. Our results showed a significant decrease of catalase and superoxide dismutase activities and an increase in lipid peroxidation compared to control group after BLM injection. Treatment with TVE (200 mg/kg) was able to normalize the level of these oxidative markers and to decrease collagen accumulation compared to BLM group. Moreover, this high dose of TVE have no renal or hepatic cytotoxic effects. This study allowed us to conclude that thyme extract has a strong antioxidant and antifibrotic activities due to its high content of polyphenols.

Metabolism and transcriptome profiling provides insight into the genes and transcription factors involved in monoterpene biosynthesis of borneol chemotype of Cinnamomum camphora induced by mechanical damage

Background

The borneol chemotype of Cinnamomum camphora (BCC), a monoterpene-rich woody plant species, is the sole source prescribed by the Chinese Pharmacopoeia for the production of natural D-borneol, a major monoterpene in BCC used for millennia as a topical analgesic in China. Nevertheless, the possible gene-regulatory roles of transcription factors (TFs) in BCC’s monoterpenoid biosynthesis remained unknown. Here, a joint analysis of the transcriptome and terpenoid metabolome of BCC induced by mechanical damage (MD) was used to comprehensively explore the interaction between TFs and terpene synthase (TPS) unigenes that might participate in monoterpene biosynthesis in BCC.

Results

Gas chromatography–mass spectrometry analysis detected 14 monoterpenes and seven sesquiterpenes. All but two monoterpenes underwent a significantly increased accumulation after the MD treatment. RNA sequencing data revealed that 10 TPS, 82 MYB, 70 AP2/ERF, 38 BHLH, 31 WRKY, and 29 bZIP unigenes responded to the MD treatment. A correlation analysis revealed that three monoterpene synthase genes (CcTPS1, CcTPS3, CcTPS4) highly correlated with multiple monoterpenes, namely D-borneol, camphor, and bornyl acetate, which could be responsible for monoterpenoid biosynthesis in BCC. Furthermore, five WRKY, 15 MYB, 10 ERF/AP2, five bZIP, and two BHLH genes had strong, positive correlations with CcTPS1 or CcTPS4, judging by their high coefficient values (R² > 0.8). The bioinformatics results were verified by quantitative real-time PCR.

Conclusion

This study provides insight into the genes involved in the biosynthesis and regulation of monoterpene in BCC and thus provides a pool of candidate genes for future mechanistic analyses of how monoterpenes accumulate in BCC.