Simultaneous characterization and quantification of 17 main compounds in Rabdosia rubescens by high performance liquid chromatography

Light-Emitting Diodes Modify Medicinal Quality of Mown Rabdosia rubescens, with Changes in Growth, Physiology, and Antioxidant Activity, under Drought Stress

Medicinal plants accommodated by understory habitats can easily suffer over-exploitation in the heavy harvest of natural products. It is necessary to develop a sustainable cultural protocol to provide high-quality stocks for efficient regeneration. Drought places stress on medicinal plants during their culture by limiting new sprout growth and reducing the quality of medicinal extracts. Artificial mediating approaches should be considered in a sustainable regime of medicinal plant culture to test the potential tradeoff between resistance to drought and production ability. In this study, Rabdosia rubescens seedlings were raised in three light-emitting diode (LED) spectra from red (71.7% red, 14.6% green, 13.7% blue), green (26.2% red, 17.4% green, 56.4% blue), and blue (17.8% red, 33.7% green, 48.5% blue) lights. Mown seedlings were subjected to a simulated drought event. Drought stressed the seedlings by reducing the growth, dry mass, nitrogen (N) uptake, and oridonin content. Mowing increased the oridonin content but decreased total C and N accumulation and the δ13C level. The red light benefitted starch accumulation only under the well-watered condition, and the green light induced an upregulation of δ13C but decreased antioxidant activity. Oridonin content was negatively associated with combined δ13C and catalase activity. Overall, either mowing or blue light can be recommended for the culture of R. rubescens to increase oridonin content, alleviating some of the negative consequences of drought.

Oridonin alleviates hyperbilirubinemia through activating LXRα-UGT1A1 axis

Hyperbilirubinemia is a serious hazard to human health due to its neurotoxicity and lethality. So far, successful therapy for hyperbilirubinemia with fewer side effects is still lacking. In this study, we aimed to clarify the effects of oridonin (Ori), an active diterpenoid extracted from Rabdosia rubescens, on hyperbilirubinemia and revealed the underlying molecular mechanism in vivo and in vitro. Here, we showed that liver X receptor alpha (LXRα) deletion eliminated the protective effect of Ori on phenylhydrazine hydrochloride-induced hyperbilirubinemia mice, indicating that LXRα acted as a key target for Ori treatment of hyperbilirubinemia. Ori significantly increased the expression of LXRα and UDP-glucuronosyltransferase 1A1 (UGT1A1) in the liver of wild-type (WT) mice, which were lost in LXRα^-/- mice. Ori or LXR agonist GW3965 also reduced lipopolysaccharide/D-galactosamine-induced hyperbilirubinemia via activating LXRα/UGT1A1 in WT mice. Liver UGT1A1 enzyme activity was elevated by Ori or GW3965 in WT mice. Further, Ori up-regulated LXRα gene expression, increased its nuclear translocation and stimulated UGT1A1 promoter activity in HepG2 cells. After silencing LXRα by siRNA, Ori-induced UGT1A1 expression was markedly reduced in HepG2 cells and primary mouse hepatocytes. Taken together, Ori stimulated the transcriptional activity of LXRα, resulting in the up-regulation of UGT1A1. Therefore, Ori or its analogs might have the potential to treat hyperbilirubinemia-related diseases through modulating LXRα-UGT1A1 signaling.

A Study on the Phytotoxic Potential of the Seasoning Herb Marjoram (Origanum majorana L.) Leaves

In the search of new alternatives for weed control, spices appear as an option with great potential. They are rich in bioactive natural products and edible, which might minimize toxicity hazard. Marjoram (Origanum majorana L.) is an aromatic herb that has been widely employed as a seasoning herb in Mediterranean countries. Although marjoram boasts a plethora of therapeutic properties (painkiller, antibiotic, treatment for intestinal disorders, etc.), the potential for its extracts for weed control is still to be more thoroughly explored. In order to determine their phytotoxic potential, marjoram leaves were subjected to different bioguided extraction processes, using water, ethyl acetate, acetone or methanol. The most active extract (acetone) was sequentially fractionated to identify its most active compounds. This fractionation led to the isolation and identification of 25 compounds that were classified as monoterpenes, diterpenes or flavonoids. Among them, a new compound named majoradiol and several compounds are described in marjoram for the first time. The phytotoxicity of the major compounds to etiolated wheat coleoptiles was compared against that of the commercial herbicide (Logran^®), with similar or higher activity in some cases. These results confirm the extraordinary potential of the extracts from this edible plant to develop safer and more environmentally friendly herbicides.

Simultaneous characterization and quantification of flavonoids in Morus australis root as potential hepatoprotective nutraceutical

Morus australis distributed widely in China has high value in food and agriculture. Twelve phenolic compounds were isolated and identified as major constituents of M. australis root from Shaanxi province, China, while the protective effect of M. australis root on liver injury has never been determined in detail. In this study, the hepatoprotective ability of M. australis root was investigated in vivo and in vitro. The ethanol-water extract prepared from M. australis root showed protection on alcohol-induced liver damage in mice by decreasing the levels of serum alanine aminotransferase, aspartate transaminase, triacylglycerol and malondialdehyde, and by increasing glutathione contents. Furthermore, among 12 major constituents of M. australis root, 10 flavonoids (especially 1) showed protection against carbon tetrachloride (CCl₄ )-intoxicated HepG2 cell lines by decreased lactic dehydrogenase levels. In addition a validated HPLC-DAD method was established for the quantitative analysis of 10 flavonoids in the bioactive extract. PRACTICAL APPLICATIONS: Our results showed that M. australis root extract significantly alleviated the liver damage in mice. Ten flavonoids from the root of this plant exhibited protection on CCl₄ -intoxicated HepG2 cell lines. This study suggests that Morus australis root has hepatoprotective potential as a promising supplement for the prevention and treatment of liver diseases.

A New Method to Extract Oridonin and Rosmarinic Acid Simultaneously from Rabdosia Rubescens

A new approach employing conventional solid-liquid extraction has been developed to separate oridonin (ORI) and rosmarinic acid (RA) simultaneously from Rabdosia rubescens. The effects of important parameters were optimized by response surface methodology (RSM) method based on five-level, three-variable central composite design (CCD). A higher recovery rate of 65 % ORI and 88.5 % RA in conjunction with a maximum yield of 9.6 % on the plant dry weight was obtained when liquid-to-solid ratio (LtS) was 12 ml/g, ethanol content (EtC) of 80 %, extract time for 75 min. A quadratic equation was proposed to correlate the independent variables for maximum 9.6 % yield and it is in consistence with the predictive value of 9.52 %. High performance liquid chromatography (HPLC) analysis indicated that ORI and RA in final product were 6.65 times and 9.1 times richer than raw material. With the newly developed process, an extract enriched ORI and RA was obtained with fewer cost and energy.

Ponicidin inhibits pro-inflammatory cytokine TNF-α-induced epithelial-mesenchymal transition and metastasis of colorectal cancer cells via suppressing the AKT/GSK-3β/Snail pathway

Ponicidin (PON), a natural diterpenoid compound, has been shown to exhibit potent anticancer activities in a wide variety of cancers, including colorectal cancer (CRC). Nevertheless, the precise mechanisms underlying the anti-metastasis effect of PON have not yet been completely defined. The present study was designed to uncover the inhibitory effect of PON on epithelial-mesenchymal transition (EMT), migration and invasion of HCT116 cells induced by pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) in vitro, and liver metastasis in vivo. Briefly, cell proliferation was assessed by Cell Counting Kit-8 assay, followed by wound healing and transwell assays to evaluate cell migration and invasion. The EMT-related molecular markers were determined through quantitative real-time polymerase chain reaction (qPCR), immunofluorescence (IF), western blot (WB), and immunohistochemistry (IHC). Additionally, WB was used to assess the expression of AKT, phosphorylated AKT (p-AKT), GSK-3β, and phosphorylated GSK-3β (p-GSK-3β). As a result, PON could effectively suppress EMT, migration, and invasion in HCT116 cells in vitro, and liver metastasis of HCT116 cells in vivo. Additionally, PON administration also dramatically altered the expression of EMT-associated markers such as E-cadherin, N-cadherin, and Vimentin, and suppressed the expression of p-AKT, p-GSK-3β and transcription factor, Snail in a dose-dependent manner. Moreover, the incidence of liver metastasis in the control group was 100% and although the incidence of liver metastasis did not decrease, the number of metastatic nodules in the livers of each PON dose group decreased by (34 ± 4.2)%, (64 ± 3.6)%, and (76 ± 5.3)%, respectively, compared to the control group. Collectively, these findings indicated that targeting the AKT/GSK-3β/Snail pathway by PON might be a promising treatment for TNF-α-induced EMT and metastasis of CRC.