Brucea javanica oil alleviates intestinal mucosal injury induced by chemotherapeutic agent 5-fluorouracil in mice.

Background: Brucea javanica (L.) Merr, has a long history to be an anti-dysentery medicine for thousand of years, which is commonly called "Ya-Dan-Zi" in Chinese. The common liquid preparation of its seed, B. javanica oil (BJO) exerts anti-inflammatory action in gastrointestinal diseases and is popularly used as an antitumor adjuvant in Asia. However, there is no report that BJO has the potential to treat 5-Fluorouracil (5-FU)-induced chemotherapeutic intestinal mucosal injury (CIM). Aim of the study: To test the hypothesis that BJO has potential intestinal protection on intestinal mucosal injury caused by 5-FU in mice and to explore the mechanisms. Materials and methods: Kunming mice (half male and female), were randomly divided into six groups: normal group, 5-FU group (5-FU, 60 mg/kg), LO group (loperamide, 4.0 mg/kg), BJO group (0.125, 0.25, 0.50 g/kg). CIM was induced by intraperitoneal injection of 5-FU at a dose of 60 mg/kg/day for 5 days (from day 1 to day 5). BJO and LO were given orally 30 min prior to 5-FU administration for 7 days (from day 1 to day 7). The ameliorative effects of BJO were assessed by body weight, diarrhea assessment, and H&E staining of the intestine. Furthermore, the changes in oxidative stress level, inflammatory level, intestinal epithelial cell apoptosis, and proliferation, as well as the amount of intestinal tight junction proteins were evaluated. Finally, the involvements of the Nrf2/HO-1 pathway were tested by western blot. Results: BJO effectively alleviated 5-FU-induced CIM, as represented by the improvement of body weight, diarrhea syndrome, and histopathological changes in the ileum. BJO not only attenuated oxidative stress by upregulating SOD and downregulating MDA in the serum, but also reduced the intestinal level of COX-2 and inflammatory cytokines, and repressed CXCL1/2 and NLRP3 inflammasome activation. Moreover, BJO ameliorated 5-FU-induced epithelial apoptosis as evidenced by the downregulation of Bax and caspase-3 and the upregulation of Bcl-2, but enhanced mucosal epithelial cell proliferation as implied by the increase of crypt-localized proliferating cell nuclear antigen (PCNA) level. Furthermore, BJO contributed to the mucosal barrier by raising the level of tight junction proteins (ZO-1, occludin, and claudin-1). Mechanistically, these anti-intestinal mucositis pharmacological effects of BJO were relevant for the activation of Nrf2/HO-1 in the intestinal tissues. Conclusion: The present study provides new insights into the protective effects of BJO against CIM and suggests that BJO deserves to be applied as a potential therapeutic agent for the prevention of CIM.

Brusatol-Enriched Brucea javanica Oil Ameliorated Dextran Sulfate Sodium-Induced Colitis in Mice: Involvement of NF-κB and RhoA/ROCK Signaling Pathways.

Brucea javanica oil (BJO) is beneficial for the treatment of ulcerative colitis (UC), and that quassinoids in particular brusatol are bioactive components. However, it is still uncertain whether or not other components in BJO, such as oleic acid and fatty acids, have an anti-UC effect. The present study is aimed at comparing the anti-UC effects between brusatol-enriched BJO (BE-BJO) and brusatol-free BJO (BF-BJO) and at exploring the effects and mechanisms of BE-BJO on colon inflammation and intestinal epithelial barrier function. Balb/C mice received 3% (wt/vol) DSS for one week to establish the UC model. Different doses of BE-BJO, BF-BJO, or BJO were treated. The result illustrated that BE-BJO alleviated DSS-induced loss of body weight, an increase of disease activity index (DAI), and a shortening of colon, whereas BF-BJO did not have these protective effects. BE-BJO treatment improved the morphology of colon tissue, inhibited the production and release of TNF-α, IFN-γ, IL-6, and IL-1ß in the colon tissue, and reversed the decreased expressions of ZO-1, occludin, claudin-1, and E-cadherin induced by DSS but augmented claudin-2 expression. Mechanistically, BE-BJO repressed phosphorylation of NF-κB subunit p65, suppressed RhoA activation, downregulated ROCK, and prevented phosphorylation of myosin light chain (MLC) in DSS-treated mice, indicating that the protective effect of BE-BJO is attributed to suppression of NF-κB and RhoA/ROCK signaling pathways. These findings confirm that brusatol is an active component from BJO in the treatment of UC.

Apoptotic activities of brusatol in human non-small cell lung cancer cells: Involvement of ROS-mediated mitochondrial-dependent pathway and inhibition of Nrf2-mediated antioxidant response.

Brusatol occurs as a characteristic bioactive principle of Brucea javanica (L.) Merr., a traditional medicinal herb frequently employed to tackle cancer in China. This work endeavored to unravel the potential anti-cancer activity and action mechanism of brusatol against non-small cell lung cancer (NSCLC) cell lines. The findings indicated that brusatol remarkably inhibited the growth of wild-type NSCLC cell lines (A549 and H1650) and epidermal growth factor receptor-mutant cell lines (PC9 and HCC827) in a dose- and time-related fashion, and profoundly inhibited the clonogenic capability and migratory capacity of PC9 cells. Treatment with brusatol resulted in significant apoptosis in PC9 cells, as evidenced by Hoechst 33342 staining and flow cytometric analysis. The apoptotic effect was closely related to induction of G0-G1 cell cycle arrest, stimulation of reactive oxygen species (ROS) and malondialdehyde, decrease of glutathione levels and disruption of mitochondrial membrane potential. Furthermore, pretreatment with N-acetylcysteine, a typical ROS scavenger, markedly ameliorated the brusatol-induced inhibition of PC9 cells. Western blotting assay indicated that brusatol pronouncedly suppressed the expression levels of mitochondrial apoptotic pathway-associated proteins Bcl-2 and Bcl-xl, accentuated the expression of Bax and Bak, and upregulated the protein expression of XIAP, cleaved caspase-3/pro caspase-3, cleaved caspase-8/pro caspase-8, and cleaved PARP/total PARP. In addition, brusatol significantly suppressed the expression of Nrf2 and HO-1, and abrogated tBHQ-induced Nrf2 activation. Combinational administration of brusatol with four chemotherapeutic agents exhibited marked synergetic effect on PC9 cells. Together, the inhibition of PC9 cells proliferation by brusatol might be intimately associated with the modulation of ROS-mediated mitochondrial-dependent pathway and inhibition of Nrf2-mediated antioxidant response. This novel insight might provide further evidence to buttress the antineoplastic efficacy of B. javanica, and support a role for brusatol as a promising anti-cancer candidate or adjuvant to current chemotherapeutic medication in the therapy of EGFR-mutant NSCLC.

Rhamnocitrin extracted from Nervilia fordii inhibited vascular endothelial activation via miR-185/STIM-1/SOCE/NFATc3.

BACKGROUND: Vascular endothelial activation is pivotal for the pathological development of various infectious and inflammatory diseases. Therapeutic interventions to prevent endothelial activation are of great clinical significance to achieve anti-inflammatory strategy. Previous studies indicate that the total flavonoids from the endemic herbal medicine Nervilia fordii (Hance) Schltr exerts potent anti-inflammatory effect and protective effect against endotoxin lipopolysaccharide (LPS)-induced acute lung injury, and shows clinical benefit in severe acute respiratory syndromes (SARS). However, the exact effective component of Nervilia fordii and its potential mechanism remain unknown. PURPOSE: The aim of this study was to investigate the effect and mechanism of rhamnocitrin (RH), a flavonoid extracted from Nervilia fordii, on LPS-induced endothelial activation. METHODS: The in vitro endothelial cell activation model was induced by LPS in human umbilical vein endothelial cells (HUVECs). Cell viability was measured to determine the cytotoxicity of RH. RT-PCR, Western blot, fluorescent probe and immunofluorescence were conducted to evaluate the effect and mechanism of RH against endothelial activation. RESULTS: RH was extracted and isolated from Nervilia fordii. RH at the concentration from 10-7 M-10-5 M inhibited the expressions of interlukin-6 (IL-6) and -8 (IL-8), monocyte chemotactic protein-1 (MCP-1), intercellular adhesion molecule-1 (ICAM-1), vascular cell-adhesion molecule-1 (VCAM-1), and plasminogen activator inhibitor-1 (PAI-1) in response to LPS challenge. Mechanistically, RH repressed calcium store-operated Ca2+ entry (SOCE) induced by LPS, which is due to downregulation of stromal interaction molecule-1 (STIM-1) following upregulating microRNA-185 (miR-185). Ultimately, RH abrogated LPS-induced activation of SOCE-mediated calcineurin/NFATc3 (nuclear factor of activated T cells, cytoplasmic 3) signaling pathway. CONCLUSION: The present study identifies RH as a potent inhibitor of endothelial activation. Since vascular endothelial activation is a pivotal cause of excessive cytokine production, leading to cytokine storm and severe pathology in infectious diseases such as SARS and the ongoing COVID-19 pneumonia disease, RH might suggest promising therapeutic potential in the management of cytokine storm in these diseases.

Apoptosis induced by bruceine D in human non­small­cell lung cancer cells involves mitochondrial ROS­mediated death signaling.

Bruceine D is one of the active components of Brucea javanica (L.) Merr., which is widely used to treat cancer in China. The aim of the present study was to evaluate the potential effect of bruceine D against non­small­cell lung cancer (NSCLC) cells and delineate its underlying mechanisms. The results indicated that treatment with bruceine D markedly inhibited the proliferation of wild­type NSCLC cells and epidermal growth factor receptor­mutant cells in a dose­ and time­dependent manner, and significantly decreased the colony­forming ability and migration of A549 cells. Hoechst 33342 staining and flow cytometric analysis demonstrated that treatment with bruceine D effectively induced apoptosis of A549 cells. In addition, the proapoptotic effect of bruceine D was found to be associated with G0­G1 cell cycle arrest, accumulation of intracellular reactive oxygen species (ROS) and malondialdehyde, depletion of glutathione levels and disruption of mitochondrial membrane potential. Additionally, pretreatment with N­acetylcysteine, a ROS scavenger, significantly attenuated the bruceine D­induced inhibition in A549 cells. Western blotting demonstrated that treatment with bruceine D significantly suppressed the expression of the anti­apoptotic proteins Bcl­2, Bcl­xL and X­linked inhibitor of apoptosis, enhanced the expression levels of apoptotic proteins Bax and Bak, and inhibited the expression of pro­caspase­3 and pro­caspase­8. Based on these results, it may be suggested that inhibition of A549 NSCLC cell proliferation by bruceine D is associated with the modulation of ROS­mitochondrial­mediated death signaling. This novel insight may provide further evidence to verify the anticancer efficacy of B. javanica, and support a role for bruceine D in the anti­NSCLC treatment.

Protective Effect of Bruguiera gymnorrhiza (L.) Lam. Fruit on Dextran Sulfate Sodium-Induced Ulcerative Colitis in Mice: Role of Keap1/Nrf2 Pathway and Gut Microbiota.

Bruguiera gymnorrhiza (BG), a medicinal mangrove, and its fruit (a food material) (BGF), have traditionally been used to treat diarrhea (also known as ulcerative colitis) in folk medicine. However, the mechanism of action against colitis remains ambiguous. This study aimed to investigate the potential efficacy and mechanism of BGF on experimental colitis. Colitis was induced by oral intake of dextran sulfate sodium (DSS) and treated with aqueous extract of BGF (25, 50 and 100 mg/kg) for a week. The Disease Activity Index (DAI), colon length, and histological changes of colon were analyzed. The inflammatory and oxidative stress status was explored. The protein expression of Nrf2 and Keap1 in the colon was detected by Western blotting. The mRNA expression of Nrf2 downstream genes (GCLC, GCLM, HO-1 and NQO1) was determined by RT-PCR. Furthermore, the effect on intestinal flora was analyzed. Results indicated that BGF was rich in pinitol, and showed strong antioxidative activity in vitro. Compared with the DSS model, BGF effectively reduced the body weight loss and DAI, restored the colon length, repaired colonic pathological variations, and decreased the histological scores, which was superior to salicylazosulfapyridine (SASP) with smaller dosage. Moreover, BGF not only abated the levels of MDA and inflammatory mediators (TNF-α, IL-6, IL-1ß, and IFN-γ), increased the level of IL-10, but also prevented the depletion of SOD and GSH. BGF upregulated the protein level of nuclear Nrf2 and mRNA levels of GCLC, GCLM, HO-1 and NQO1, while significantly inhibited the protein expression of Keap1 and cytosolic Nrf2. Besides, BGF promoted the growth of probiotics (Bifidobacterium, Anaerotruncus, and Lactobacillus) in the gut, and inhibited the colonization of pathogenic bacteria (Bacteroides and Streptococcus), which contributed to the maintenance of intestinal homeostasis. BGF possessed protective effect against DSS-induced colitis. The potential mechanism of BGF may involve the amelioration of inflammatory and oxidative status, activation of Keap1/Nrf2 signaling pathway, and maintenance of micro-ecological balance of the host. This study provides experimental evidence for the traditional application of BGF in the treatment of diarrhea, and indicates that BGF may be a promising candidate against colitis.