Anti-Cancer Effects of a New Herbal Medicine PSY by Inhibiting the STAT3 Signaling Pathway in Colorectal Cancer Cells and Its Phytochemical Analysis

Colorectal cancer (CRC) is an inflammation-associated common cancer worldwide. Paejang-san and Mori Cortex Radicis have been traditionally used for treating intestinal inflammatory diseases in Korea and China. In the present study, we developed a new herbal formula as an alternative to CRC treatments, which is composed of two main components of Paejangsan (Patriniae Radix (Paejang in Korean) and Coix Seed (Yiyiin in Korean)), and Mori Cortex Radicis (Sangbekpi in Korean) based on the addition and subtraction theory in traditional medicine, hence the name PSY, and explored the potential therapeutic effects of the new formula PSY in human CRC cells by analyzing viability, cell cycle and apoptosis. We found that PSY ethanol extract (EtOH-Ex), but not water extract, significantly suppressed the viability of human CRC cells, and synergistically decreased the cell proliferation compared to each treatment of Patriniae Radix and Coix Seed extract (PY) or Mori Cortex Radicis extract (S), suggesting the combination of PY and S in a 10-to-3 ratio for the formula PSY. PSY EtOH-Ex in the combination ratio reduced cell viability but induced cell cycle arrest at the G₂/M and sub-G₁ phases as well as apoptosis in CRC cells. In addition, the experimental results of Western blotting, immunofluorescence staining and reporter assays showed that PSY also inhibited STAT3 by reducing its phosphorylation and nuclear localization, which resulted in lowering STAT3-mediated transcriptional activation. In addition, PSY regulated upstream signaling molecules of STAT3 by inactivating JAK2 and Src and increasing SHP1. Moreover, the chemical profiles of PSY from UPLC-ESI-QTOF MS/MS analysis revealed 38 phytochemicals, including seven organic acids, eight iridoids, two lignans, twelve prenylflavonoids, eight fatty acids, and one carbohydrate. Furthermore, 21 potentially bioactive compounds were highly enriched in the PSY EtOH-Ex compared to the water extract. Together, these results indicate that PSY suppresses the proliferation of CRC cells by inhibiting the STAT3 signaling pathway, suggesting PSY as a potential therapeutic agent for treating CRC and 21 EtOH-Ex-enriched phytochemicals as anti-cancer drug candidates which may act by inhibiting STAT3.

Mori Cortex Radicis extract inhibits human norovirus surrogate in simulated digestive conditions

Norovirus is a major cause of acute gastroenteritis globally, resulting in enormous health and societal costs. In this study, the antiviral activities of Mori Cortex Radicis (MCR) extract and its bioactive flavonoids, morusin and kuwanon G, were tested against murine norovirus (MNV), a human norovirus surrogate, using plaque assay. The antiviral activity was confirmed in simulated digestive conditions, including simulated saliva fluid (SSF), simulated gastric fluid (SGF), and simulated intestinal fluid (SIF). Pre-treatment of MNV with MCR extract at 1000 µg/mL showed antiviral activity with a 1.1-log reduction. Morusin and kuwanon G also demonstrated a 1.0-log and 0.6-log reductions of MNV titers, respectively, at 100 µM. MCR extract at a concentration of 2 mg/mL in SSF, SGF, and SIF markedly reduced MNV titers by 1.8, 1.9, and 1.5 logs, respectively. Therefore, these data suggest that MCR extract can be used to control norovirus infectivity.

Effects of Morus root bark extract and active constituents on blood lipids in hyperlipidemia rats

OBJECTIVE

Chinese crude drug Mori Cortex Radicis (the root cortex of Morus species) has been used as a folk medicine to treat hypertension, diabetes, as well as in expectorant, diuretic agents. This investigation aims to study the anti-hyperlipidemia effects of Mori Cortex Radicis (MCR) extracts in hyperlipidemic rat models and the potential therapeutic activities of compounds isolated from the extracts.

MATERIALS AND METHODS

The effects of MCR on hypolipidemic parameters were investigated using Wistar rats induced by high-lipid emulsion. Sixty healthy Wistar rats were randomly divided into 6 groups: normal group, hyperlipidaemia model group, simvastatin, and high-, medium- and low-dose MCR extracts. After four weeks, body weight, total cholesterol (TC), triglycerides (TG), high and low-density lipoproteins (HDL, LDL), as well as aspartate aminotransferase (AST), alanine aminotransferase (ALT) were measured. To further investigation, four major active compounds were isolated from extracts through high performance liquid chromatography (HPLC) and their diacylglycerol acyltransferase 1 (DGAT1) inhibitory activity was evaluated.

RESULTS

MCR dose-dependently reduced serum TC, TG, LDL-C, inhibited the activity of ALT, AST, and increased HDL-C. Furthermore, in vitro biochemistry tests revealed that four active isolates showed moderate inhibitory activity against DGAT1 with IC50 values ranging from 62.1 ± 1.2 to 99.3 ± 2.3 µM.

CONCLUSIONS

The results demonstrated that MCR could effectively ameliorate hyperlipidaemia and inhibit DGAT1 that a key enzyme closely related to hyperlipidaemia and type 2 diabetes. It may provide a new pharmacological basis for treating hyperlipidaemia and related diseases using MCR.

Effect of Kuwanon G isolated from the root bark of Morus alba on ovalbumin-induced allergic response in a mouse model of asthma

The root bark of Morus alba L. (Mori Cortex Radicis; MCR) is traditionally used in Korean medicine for upper respiratory diseases. In this study, we investigated the antiasthmatic effect of kuwanon G isolated from MCR on ovalbumin (OVA)-induced allergic asthma in mice. Kuwanon G (1 and 10 mg/kg) was administered orally in mice once a day for 7 days during OVA airway challenge. We measured the levels of OVA-specific IgE and Th2 cytokines (IL-4, IL-5, and IL-13) in the sera or bronchoalveolar lavage (BAL) fluids and also counted the immune cells in BAL fluids. Histopathological changes in the lung tissues were analyzed. Kuwanon G significantly decreased the levels of OVA-specific IgE and IL-4, IL-5, and IL-13 in the sera and BAL fluids of asthma mice. Kuwanon G reduced the numbers of inflammatory cells in the BAL fluids of asthma mice. Furthermore, the pathological feature of lungs including infiltration of inflammatory cells, thickened epithelium of bronchioles, mucus, and collagen accumulation was inhibited by kuwanon G. These results indicate that kuwanon G prevents the pathological progression of allergic asthma through the inhibition of lung destruction by inflammation and immune stimulation.