Danggui Shaoyao San: Chemical characterization and inhibition of oxidative stress and inflammation to treat CCl4-induced hepatic fibrosis

ETHNOPHARMACOLOGICAL RELEVANCE

Danggui Shaoyao San (DSS) has effective in treating hepatic ascites and liver disease.

AIM OF THE STUDY

To explore the chemical characterization of DSS and protective effect on CCl4-induced hepatic fibrosis and its mechanism, especially its anti-oxidative stress and anti-inflammation.

MATERIALS AND METHODS

The chemical characterization of DSS was determined by HPLC-Q-Exactive Orbitrap MS. And the antioxidant activity of DSS in vitro was determined. The hepatic fibrosis model was established using intragastric administration of 40% CCl4/soybean oil (v/v) twice weekly for 13 weeks. From 6th week, the DSS group and the positive control group were given DSS (2, 4, 8 g/kg/d) and silymarin (50 mg/kg/d), respectively. The livers of rats were examined histologically by H&E. The ALT, AST, ALB and TBIL were determined, and hepatic fibrosis markers (HA, LN, CIV, PIIINP), oxidative stress (SOD, MDA, GST, GSH) and inflammatory factor (IL-6, TNF-α) were tested using ELISA kits. In addition, the levels of TAC, TOS, LOOH and AOPP in the liver were also determined.

RESULTS

The chemical characterization of DSS was determined by HPLC-Q-Exactive Orbitrap MS. The results show that DSS mainly includes triterpenoids, monoterpenes, phenols, sesquiterpenes, butyl phthalide, etc., and DSS has good antioxidant activity in vitro. In addition, the ALT, AST and TBIL of rats were remarkably reduced after treatment with DSS at three doses. Liver histopathological analysis showed that DSS alleviated the inflammatory infiltration, hepatocyte swelling, necrosis and hepatic fibrosis induced by CCl4. DSS significantly decreased HA, IV-C, PIIINP and LN. Further determination showed that DSS significantly increased TAC, OSI and decreased TOC, LOOH and MDA, indicating that DSS could regulate redox balance and reduce lipid peroxidation in vivo. DSS also increased the activity of GST, SOD and GSH concentration. In addition, DSS also reduced IL-6 and TNF-α.

CONCLUSIONS

In this study, we described the chemical characterization of DSS and found that it has good antioxidant activity. We proved that DSS has the functions of reducing oxidative stress, anti-inflammatory, protecting liver cells and reducing hepatic fibrosis.

Modulation of carcinogenesis with selected GRAS nutraceuticals via Keap1-Nrf2 signaling pathway

Keap1-Nrf2 is a fundamental signaling cascade known to promote or prevent carcinogenesis. Extensive studies identify the key target of modulatory aspects of Keap1-Nrf2 signaling against cancer. Nutraceuticals are those dietary agents with many health benefits that have immense potential for cancer chemoprevention. The nutritional supplements known as nutraceuticals are found to be one of the most promising chemoprevention agents. Upon investigating the dual nature of Nrf2, it became clear that, in addition to shielding normal cells from numerous stresses, Nrf2 may also promote the growth of tumors. In the present review, we performed a systematic analysis of the role of 12 different nutraceuticals like curcumin, sulforaphane, resveratrol, polyunsaturated fatty acids (PUFA) from fish oil, lycopene, soybean, kaempferol, allicin, thymoquinone, quercetin, gingerol, and piperine in modulating the Nrf2/Keap1 signaling mechanism. Among these, 12 Generally Recognized As Safe (GRAS) certified nutraceuticals, sulforaphane is the most extensively studied compound in modulating Keap1-Nrf signaling. Even though there is much evidence at preclinical levels, further high-quality research is still required to validate the potential role of these nutraceuticals in Keap1-Nrf2 modulation.

Cancer Chemopreventive Role of Dietary Terpenoids by Modulating Keap1-Nrf2-ARE Signaling System—A Comprehensive Update

ROS, RNS, and carcinogenic metabolites generate excessive oxidative stress, which changes the basal cellular status and leads to epigenetic modification, genomic instability, and initiation of cancer. Epigenetic modification may inhibit tumor-suppressor genes and activate oncogenes, enabling cells to have cancer promoting properties. The nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that in humans is encoded by the NFE2L2 gene, and is activated in response to cellular stress. It can regulate redox homoeostasis by expressing several cytoprotective enzymes, including NADPH quinine oxidoreductase, heme oxygenase-1, UDP-glucuronosyltransferase, glutathione peroxidase, glutathione-S-transferase, etc. There is accumulating evidence supporting the idea that dietary nutraceuticals derived from commonly used fruits, vegetables, and spices have the ability to produce cancer chemopreventive activity by inducing Nrf2-mediated detoxifying enzymes. In this review, we discuss the importance of these nutraceuticals in cancer chemoprevention and summarize the role of dietary terpenoids in this respect. This approach was taken to accumulate the mechanistic function of these terpenoids to develop a comprehensive understanding of their direct and indirect roles in modulating the Keap1-Nrf2-ARE signaling system.

Treatment with LEDs at a wavelength of 642 nm enhances skin tumor proliferation in a mouse model

Photobiomodulation (PBM) is attracting increased attention in the fields of dermatology and cosmetics. PBM with a variety of light parameters has been used widely in skin care, but can cause certain types of unwanted cells to proliferate in the skin; this can lead to skin tumors, such as papillomas and cancers. We constructed a mouse model of human skin tumors using DMBA as an initiator and TPA as a promoter, and confirmed that LEDs with a wavelength of 642 nm (red light) increased tumor size, epidermal thickness, and systemic proinflammatory cytokine levels. These results indicated that skin tumor cell proliferation may result from the use of 642 nm LEDs, suggesting the need for regulation of skin care based on LED light therapy.

Lycopene prevents carcinogen-induced cutaneous tumor by enhancing activation of the Nrf2 pathway through p62-triggered autophagic Keap1 degradation

Biologically active natural products have been used for the chemoprevention of cutaneous tumors. Lycopene is the main active phytochemical in tomatoes. We herein aimed to assess the cancer preventive effects of lycopene and to find potential molecular targets. In chemically-induced cutaneous tumor mice and cell models, lycopene attenuated cutaneous tumor incidence and multiplicity as well as the tumorigenesis of normal cutaneous cells in phase-selectivity (only in the promotion phase) manners. By utilizing a comprehensive approach combining bioinformatics with network pharmacology, we predicted that intracellular autophagy and redox status were associated with lycopene’s preventive effect on cutaneous tumors. Lycopene stimulated the activation of antioxidant enzymes and the translocation of the transcription factor Nrf2 (nuclear factor erythroid 2-related factor 2) that predominantly maintained intracellular redox equilibrium. The cancer chemopreventive effects were mediated by Nrf2. Further, lycopene enhanced the expression of autophagy protein p62. Therefore this led to the degradation of Keap1(Kelch ECH associating protein 1), the main protein locking Nrf2 in cytoplasm. In conclusion, our study provides preclinical evidence of the chemopreventive effects of lycopene on cutaneous tumors and reveals the mechanistic link between lycopene’s stimulation of Nrf2 signaling pathway and p62-mediated degradation of Keap1 via the autophagy-lysosomal pathway.

Protective effects of lycopene in cancer, cardiovascular, and neurodegenerative diseases: An update on epidemiological and mechanistic perspectives

Recent mechanistic and epidemiological studies have provided insights into health benefits of dietary lycopene to decrease the risk and complications associated with several chronic diseases such as cardiovascular diseases (CVD), obesity, type 2 diabetes, cancer, and neurodegenerative disorders. These chronic diseases are primarily associated with oxidative stress-induced systemic and low-grade chronic inflammation. Owing to its potent antioxidant properties, lycopene can potentially alleviate enhanced levels of proinflammatory mediators (e.g., proinflammatory cytokines IL-8, -6, and -1, and oxidized phospholipids) and prevent NF-κB activation by modulating oxidative stress. Moreover, lycopene serves as a precursor for various oxidative cleavage products and metabolites including Apo-8'-, apo-10'-, and apo-12'-lycopenals that can interact with multiple transcription factors (e.g., Nrf2, RARs, RXRs, and PPARs) to overexpress antioxidant and cytoprotective Phase II enzymes and other growth-stimulating proteins (e.g., brain-derived neurotrophic factor (BDNF) for enhanced neuroprotection. These events altogether can protect the body from chronic inflammatory disorders. In the present review, the latest mechanistic development from cell and animal models and results of case-control, cohort, and randomized trials are discussed to support the protective part of lycopene in cancer, CVD, and neurodegenerative disorders. This review focuses on cellular and molecular events involved in protective effects of lycopene. Although molecular and cellular mechanisms involved in health-promoting activities of lycopene have been reported, no detailed mechanistic studies have been published. Hence, future studies should be conducted to elucidate the mechanistic role(s) of lycopene-derived oxidation products in modulating cellular signaling.

Semaphoring 4D is required for the induction of antioxidant stress and anti-inflammatory effects of dihydromyricetin in colon cancer

Semaphorin 4D (Sema4D) has been involved in cancer progression, the expression of which is associated with the poor clinical outcomes of some cancer patients. Dihydromyricetin (DMY) has antitumor potentials for different types of human cancer cells. However, the pharmacological effects of DMY on colon cancer (CC) or the regulatory effects of Sema4D on this process remain largely unknown. In the present study, we aimed to evaluate the effects of DMY on CC, and to elucidate the role of Sema4D in DMY-induced antitumor effects. DMY inhibited the proliferation and growth of Colo-205 colon cancer cells significantly in vivo and in vitro. DMY inhibited reactive oxygen species (ROS) and malondialdehyde (MDA) levels, but increased glutathione (GSH) level. Moreover, the activities of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and heme oxygenase 1 (HO-1) were enhanced by DMY treatment in vitro, showing strong anti-oxidative stress effect. In addition, DMY inhibited the secretion of interleukin 1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor (TNF-α) in the supernatant of Colo-205 culture medium. Besides, the expressions of cyclooxygenase (COX-2) and inducible nitric oxide synthase (iNOS) were suppressed by DMY in dose-dependent manners in vivo, showing potent anti-inflammatory effect. Further investigations showed that DMY suppressed the expression and secretion of Sema4D in Colo-205 cells and tissues. Interestingly, overexpression of Sema4D significantly weakened the regulatory effects of DMY on oxidative stress. Furthermore, overexpression of Sema4D significantly attenuated the anti-inflammatory effects of DMY. Collectively, we drew a conclusion that the anti-colon cancer effect of DMY was attributed to its negative modulation on oxidative stress and inflammation via suppression of Sema4D. The findings broaden the width and depth of molecular mechanisms involved in the DMY action, facilitating the development of DMY in anti-colon cancer therapies.

Stachydrine ameliorates carbon tetrachloride-induced hepatic fibrosis by inhibiting inflammation, oxidative stress and regulating MMPs/TIMPs system in rats

Inflammation and oxidative stress are two crucial factors mediating liver fibrosis. Stachydrine (STA) is a naturally occurring compound extracted from a medicinal plant Leonuru heterophyllus, which can inhibit the proliferation and induce the apoptosis of breast cancer cells, relieve high glucose-induced endothelial cell senescence and isoproterenol-induced cardiac hypertrophy, and exert antitumor effects. However, its roles in hepatic fibrosis remain largely unknown. We aimed to evaluate the effect of STA on carbon tetrachloride (CCl₄)-induced hepatic fibrosis in rats and to elucidate the possible mechanisms. STA alleviated the pathological changes caused by CCl₄ injection in livers compared to the normal liver. Hematoxylin-eosin staining further showed that STA treatment remarkably improved the liver histology, as evidenced by mitigated hepatic steatosis, necrosis, and fibrotic septa. STA reduced the liver/body weight ratio and the serum levels of aminotransferase, aspartate aminotransferase and alkaline phosphatase. It also significantly decreased collagen deposition and hydroxyproline level. Both mRNA and protein levels of α-SMA, α1(I)-procollagen and fibronectin were decreased by STA compared to those of the model group. STA significantly inhibited the expressions of inflammatory factors interleukin-6 (IL-6), IL-8, IL-1β, tumor necrosis factor-α, inducible nitric oxide synthase and cyclooxygenase-2. It suppressed oxidative stress by decreasing malondialdehyde level as well as increasing glutathione level and enzymatic activities of superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase. STA also significantly increased the protein expressions of tissue inhibitor of metallopeptidase-1 (TIMP-1) and TIMP-2 but decreased those of matrix metalloproteinase-2 (MMP-2) and MMP-9, indicating excessive basement membrane in the fibrotic liver. Collectively, STA has potent protective effects on the liver, with therapeutic implication for liver fibrosis.

α-Mangostin inhibits DMBA/TPA-induced skin cancer through inhibiting inflammation and promoting autophagy and apoptosis by regulating PI3K/Akt/mTOR signaling pathway in mice

Skin cancer is the most common form of cancer responsible for considerable morbidity and mortality, the treatment progress of which remains slow though. Therefore, studies identifying anti-skin cancer agents that are innocuous are urgently needed. α-Mangostin, a natural product isolated from the pericarp of mangosteen fruit, has potent anti-cancer activity. However, its role in skin cancer remains unclear. The aim of this study was to evaluate the treatment effect of α-mangostin on skin tumorigenesis induced by 9,10-dimethylbenz[a]anthracene (DMBA)/TPA in mice and the potential mechanism. Treatment with α-mangostin significantly suppressed tumor formation and growth, and markedly reduced the incidence rate. α-Mangostin not only inhibited the expressions of pro-inflammatory factors, but also promoted the production of anti-inflammatory factors in tumor and blood. It induced autophagy of skin tumor and regulated the expressions of autophagy-related proteins. The protein expressions of LC3, LC3-II and Beclin1 increased whereas those of LC3-I and p62 decreased after treatment with α-mangostin. Moreover, α-mangostin promoted the apoptosis of skin tumor dose-dependently by up-regulating of Bax, cleaved caspase-3, cleaved PARP and Bad, and down-regulating of Bcl-2 and Bcl-xl. Furthermore, showed α-mangostin inhibited the PI3K/AKT/mTOR (mammalian target of rapamycin) signaling pathway, as evidenced by decreased expressions of phospho-PI3K (p-PI3K), p-Akt and p-mTOR, but did not affect the expressions of t-PI3K, t-Akt or t-mTOR. Collectively, α-mangostin suppressed murine skin tumorigenesis induced by DMBA/TPA through inhibiting inflammation and promoting autophagy and apoptosis by regulating the PI3K/Akt/mTOR signaling pathway, as a potential candidate for future clinical therapy.

Diet phytochemicals and cutaneous carcinoma chemoprevention: A review

Cutaneous carcinoma, which has occupied a peculiar place among worldwide populations, is commonly responsible for the considerably increasing morbidity and mortality rates. Currently available medical procedures fail to completely avoid cutaneous carcinoma development or to prevent mortality. Cancer chemoprevention, as an alternative strategy, is being considered to reduce the incidence and burden of cancers through chemical agents. Derived from dietary foods, phytochemicals have become safe and reliable compounds for the chemoprevention of cutaneous carcinoma by relieving multiple pathological processes, including oxidative damage, epigenetic alteration, chronic inflammation, angiogenesis, etc. In this review, we presented comprehensive knowledges, main molecular mechanisms for the initiation and development of cutaneous carcinoma as well as effects of various diet phytochemicals on chemoprevention.

Casein glycomacropeptide hydrolysate exerts cytoprotection against H2O2-induced oxidative stress in RAW 264.7 macrophages via ROS-dependent heme oxygenase-1 expression

Casein glycomacropeptide hydrolysate had antioxidant activity and exerted protective actions against H₂O₂-induced oxidative stress via induction of Nrf2-mediated HO-1 expression in RAW 264.7 macrophages.