Modified Qing-Zao-Jiu-Fei decoction attenuated pulmonary fibrosis induced by bleomycin in rats via modulating Nrf2/NF-κB and MAPKs pathways.

BACKGROUND: Qing-Zao-Jiu-Fei Decoction (QZJFD) is a famous herbal formula commonly prescribed for the treatment of lung-related diseases in the ancient and modern times. Trichosanthis Fructus (TF) and Fritillariae Thunbergii Bulbus (FTB) are widely used for treatment of cough and pulmonary disease. In order to identify a more effective formula for treatment of pulmonary fibrosis, we intend to add TF and FTB in QZJFD to form a modified QZJFD (MQZJFD). In this study, we aims to explore MQZJFD as an innovative therapeutic agent for pulmonary fibrosis using bleomycin (BLM)-treated rats and to unravel the underlying molecular mechanisms. METHODS: BLM was given to SD rats by intra-tracheal administration of a single dose of BLM (5 mg/kg). QZJFD (3 g/kg) and MQZJFD (1, 2 and 4 g/kg) was given intragastrically daily to rats for 14 days (from day 15 to 28) after BLM administration for 14 consecutive days. RESULTS: MQZJFD was found to contain 0.29% of amygdalin, 0.020% of lutin, 0.077% of glycyrrhizic acid and 0.047% of chlorogenic acid. BLM treatment could induce collagen deposition in the lung tissues of rats, indicating that the pulmonary fibrosis rat model had been successfully established. MQZJFD have better effects than the original QZJFD in reducing the pulmonary structure damage and collagen deposition of rat lung fibrosis induced by BLM. MQZJFD could reduce the hydroxyproline content in lung tissues of BLM-treated rats. The biomarkers of fibrosis such as matrix metalloproteinase 9 (MMP9), collagen I and α-smooth muscle actin (α-SMA) were remarkably reduced after treatment with MQZJFD. MQZJFD also have anti-oxidant stress effects by inhibiting the level of malondialdehyde (MDA), but enhancing the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and the level of glutathione (GSH) in the lung tissues of BLM-treated rats. Moreover, the MQZJFD markedly suppressed the over expressions of p-p65/p65 and p-IκBα/IκBα, but upregulated the Nrf2. MQZJFD also suppressed the protein expressions of p-ERK1/2/ERK1/2, p-p38/p38 and p-JNK/JNK in the lung tissues of BLM-treated rats. CONCLUSIONS: MQZJFD could improve the pulmonary fibrosis induced by BLM in rats via inhibiting the fibrosis and oxidative stress via suppressing the activation of NF-κB/Nrf2 and MAPKs pathways.

Natural Nrf2 Inhibitors: A Review of Their Potential for Cancer Treatment.

Nuclear factor erythroid 2-related factor 2 (Nrf2), a transcription factor that regulates redox homeostasis, plays a pivotal role in several cellular processes such as cell proliferation and survival, and has been found to be aberrantly activated in many cancers. As one of the key oncogenes, Nrf2 represents an important therapeutic target for cancer treatment. Research has unraveled the main mechanisms underlying the Nrf2 pathway regulation and the role of Nrf2 in promoting tumorigenesis. Many efforts have been made to develop potent Nrf2 inhibitors, and several clinical trials are being conducted on some of these inhibitors. Natural products are well-recognized as a valuable source for development of novel therapeutics for cancer. So far, a number of natural compounds have been identified as Nrf2 inhibitors, such as apigenin, luteolin, and quassinoids compounds including brusatol and brucein D. These Nrf2 inhibitors have been found to mediate an oxidant response and display therapeutic effects in different types of human cancers. In this article, we reviewed the structure and function of the Nrf2/Keap1 system and the development of natural Nrf2 inhibitors with an emphasis on their biological function on cancer. The current status regarding the Nrf2 as a potential therapeutic target for cancer treatment was also summarized. It is hoped that this review will stimulate research on naturally occurring Nrf2 inhibitors as therapeutic candidates for cancer treatment.

An herbal formula inhibits STAT3 signaling and attenuates bone erosion in collagen-induced arthritis rats.

BACKGROUND: Receptor activator of NF-κB ligand (RANKL) facilitates differentiation of osteoclast precursors into osteoclasts, resulting in bone erosion in rheumatoid arthritis (RA) patients. Fibroblast-like synoviocytes (FLS) are the main cells for producing RANKL. Signal transducer and activator of transcription 3 (STAT3) signaling is activated in FLS of RA patients (RA-FLS), which has been linked to RANKL production. A two-herb formula (RL) comprising Rosae Multiflorae Fructus and Lonicerae Japonicae Flos is traditionally used for treating RA in China. We have found that a standardized ethanolic extract of RL (RLE for short) alleviates bone erosion in collagen-induced arthritis (CIA) rats. PURPOSE: This study aimed to determine whether RLE inhibits RANKL production and osteoclastogenesis in cell and rat models, and to explore the involvement of the STAT3 pathway in this inhibition. STUDY DESIGN AND METHODS: A CIA rat model, interleukin-6/soluble interleukin-6 receptor (IL-6/sIL-6R)-stimulated RA-FLS and a co-culture system (IL-6/sIL-6R-stimulated RA-FLS/peripheral blood mononuclear cells) were used to evaluate the effects of RLE. Micro-computed tomography analysis was used to observe bone erosion in CIA rats. Tartrate-resistant acid phosphatase staining was used to evaluate osteoclastogenesis. Western blotting and ELISA assays were employed to examine protein levels. RT-qPCR was used to detect mRNA levels. STAT3-over-activated RA-FLS were used to investigate the involvement of STAT3 signaling in the anti-osteoclastogenic effects of RLE. RESULTS: RLE alleviated bone erosion in joints of CIA rats. In both synovial tissues of CIA rats and IL-6/sIL-6R-stimulated RA-FLS, RLE downregulated the protein level of RANKL. In the co-culture system, RLE significantly and dose-dependently inhibited IL-6/sIL-6R-induced osteoclastogenesis. Mechanistic studies revealed that RLE lowered the protein level of phospho-STAT3 (Tyr705) in synovial tissues of CIA rats. In IL-6/sIL-6R-stimulated RA-FLS, RLE inhibited the activation/phosphorylation of a STAT3 upstream kinase Janus kinase 2 (Tyr1007/1008) and STAT3 (Tyr705), decreased the nuclear localization of STAT3, lowered mRNA levels of STAT3-transcriptionally regulated genes IL-1ß and TNF-α. RLE's inhibitory effects on RANKL production in RA-FLS gradually decreased when IL-6/sIL-6R doses increased. Over-activation of STAT3 diminished the inhibitory effects of RLE on RANKL production in IL-6/sIL-6R-stimulated RA-FLS, and attenuated the anti-osteoclastogenic effects of RLE in the co-culture system. CONCLUSION: We, for the first time, demonstrated that suppressing STAT3 signaling contributes to the inhibition of RANKL production and osteoclastogenesis, and thereby supports the mechanisms responsible for the reduction in bone erosion in RLE-treated CIA rats. This study provides further pharmacological groundwork for developing RLE as a modern anti-arthritic drug, and supports the notion that targeting STAT3 signaling is a viable strategy for managing bone erosion.

Ribosome-Inactivating Protein α-Momorcharin Derived from Edible Plant Momordica charantia Induces Inflammatory Responses by Activating the NF-kappaB and JNK Pathways.

Alpha-momorcharin (α-MMC), a member of the ribosome-inactivating protein (RIP) family, has been found in the seeds of Momordica charantia (bitter melon). α-MMC contributes a number of pharmacological activities; however, its inflammatory properties have not been well studied. Here, we aim to determine the inflammatory responses induced by recombinant α-MMC and identify the underlying mechanisms using cell culture and animal models. Recombinant α-MMC was generated in Rosetta™(DE3)pLysS and purified by the way of nitrilotriacetic acid (NTA) chromatography. Treatment of recombinant α-MMC at 40 µg/mL exerted sub-lethal cytotoxic effect on THP-1 monocytic cells. Transcriptional profiling revealed that various genes coding for cytokines and other proinflammatory proteins were upregulated upon recombinant α-MMC treatment in THP-1 cells, including MCP-1, IL-8, IL-1ß, and TNF-α. Recombinant α-MMC was shown to activate IKK/NF-κB and JNK pathways and the α-MMC-induced inflammatory gene expression could be blocked by IKKß and JNK inhibitors. Furthermore, murine inflammatory models further demonstrated that α-MMC induced inflammatory responses in vivo. We conclude that α-MMC stimulates inflammatory responses in human monocytes by activating of IKK/NF-κB and JNK pathways, raising the possibility that consumption of α-MMC-containing food may lead to inflammatory-related diseases.