Light plays a critical role in the accumulation of chlorogenic acid in Lonicera macranthoides Hand.-Mazz.

Light has important effects on plant metabolism. However, the relationship between the chlorogenic acid (CGA) content and light in plants remains unclear. Here, we investigated the effects of shading treatment on gene expression and CGA content in Lonicera macranthoides Hand.-Mazz. (LM), a widely used medicinal plant. A total of 1891 differentially expressed genes (DEGs) were obtained in flower buds and 819 in leaves in response to light in shading treatment compared to the control sample by RNA-Seq. After shading treatment, the content of CGA in LM leaves decreased significantly by 1.78-fold, the carotenoid content increased, and the soluble sugar and starch contents significantly decreased. WGCNA and the expression of related genes verified by qRT‒PCR revealed that CGA synthesis pathway enzyme genes form a co-expression network with genes for carbohydrate synthesis, photosynthesis, light signalling elements, and transcription factor genes (TFs) that affect the accumulation of CGA. Through a virus-induced gene silencing (VIGS) system and CGA assay in Nicotiana benthamiana (NB), we determined that downregulation of NbHY5 expression decreased the CGA content in NB leaves. In this study, we found that light provides energy and material for the accumulation of CGA in LM, and light affects the expression of CGA accumulation-related genes. Our results show that different light intensities have multiple effects on leaves and flower buds in LM and are able to coregulate LmHY5 expression and CGA synthesis.

Transcriptome analysis of three cultivars of Poria cocos reveals genes related to the biosynthesis of polysaccharides.

Poria cocos (P. cocos) polysaccharides (PCPs) are used to improve immunity and possess antitumor activities. We compared three cultivars of P. cocos (5.78, XJ 28 and JHYH) PCP contents. Then we determined that malZ, galA, SORD, gnl and bglX are key enzymes within the PCP biosynthetic pathway by using HiSeq2500 transcriptome and qRT-PCR validation. Our results provide more detailed information about the PCP biosynthesis pathway at the molecular level in P. cocos and establish the functions for the molecular breeding to produce polysaccharides in general for therapeutic use in Chinese medicinal plants.

Tetrastigma hemsleyanum (Sanyeqing) root tuber extracts induces apoptosis in human cervical carcinoma HeLa cells.

AIM OF THE STUDY: Tetrastigma hemsleyanum (Sanyeqing) is traditionally used as a folk medicine for the treatment of cancer. However, the underlying mechanisms remain unclear. The purpose of this study was to investigate the possible mechanisms by which petroleum ether fraction (PEF) of Sanyeqing has anti-tumor activity on HeLa cells. METHODS: The chemical components of PEF were analyzed by gas chromatography-mass spectrometry. The cytotoxicity of PEF on HeLa cells was measured by MTT assay. Apoptosis was evaluated by phosphatidylserine translocation, mitochondrial membrane potential (Δψm) changes and the activation of caspase-3, caspase-8 and caspase-9. The levels in T-SOD, CAT, GSH-PX and MDA were measured. RESULTS: PEF of Sanyeqing inhibited the growth and induced apoptosis of HeLa cells in dose- and time-dependent manner. PEF triggered intrinsic apoptotic pathway indicated by the loss of mitochondrial membrane potential and the activation of caspase-9 and caspase-3. In addition, PEF activated extrinsic apoptotic pathway indicated by the activation of caspase-8. Furthermore, PEF decreased T-SOD, CAT, GSH-PX activities and increased MDA level. Chemical analysis revealed the presence of fatty acids and phytosterol in PEF. CONCLUSIONS: PEF of Tetrastigma hemsleyanum Diels et. Gilg (Sanyeqing) exhibits cytotoxic effects, triggers both extrinsic and intrinsic apoptotic pathways, and augments oxidative stress in cervical carcinoma HeLa cells. Sanyeqing has strong potential to be developed as an agent for the treatment of cervical cancer.