Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and the most common type of liver cancer. The 5-year relative survival rate is about 7%
and causes more than six leading deaths annually worldwide. It represents the third cause of cancer-related deaths and the first cause of death amongst cirrhotic patients.
Hepatitis viral infection, food additives, alcohol, fungal toxins (afla toxins), toxic industrial chemicals, air and water pollutants are the major risk factors of HCC [1,2].
N-nitrosodiethylamine (DEN) is a potent hepatocarcinogenic nitrosamine present in tobacco smoke, water, cheddar cheese, cured and fried meals, occupational settings, cosmetics, agricultural chemicals and pharmaceutical agents [3,4]. DEN produces the pro-mutagenic products, O6-ethyl deoxy guanosine and O4 and O6-ethyl deoxy thymidine in livers leading to oxidative stress and inflammation in early stage and HCC in later status [3-5]. However, the detailed progress and mechanism for DEN-induced a simulated inflammation, fibrosis, and HCC in rats is not clearly defined.
Inflammation and oxidative stress contribute to liver injury. Overproduction of reactive oxygen species (ROS) including O2-, H2O2 and NO, can cause lipid
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peroxidation, protein oxidation, DNA damage and mutagenesis associated with various stages of liver injury [4,6]. The main sources of ROS may derive from the mitochondria of hepatocytes, the activated macrophages (ED-1; Kupffer cells), and the infiltrating neutrophils [7]. Induction of cytochrome P4502E1 (CYP2E1) and inducible nitric oxide synthase (iNOS) enhances further oxidative stress in the damaged liver [8]. ROS can also trigger translocation of nuclear factor-kappa B (NF-κB) to nucleus [9] and activation of several inflammatory signaling to release cytokines and adhesion molecules that contribute to further production of ROS, inflammatory response, and consecutive programmed apoptotic and autophagic cell death [2,10]. The increased ROS can enhance Bax/Bcl-2 ratio, caspase 3 expression, and poly-(ADP-ribose)-polymerase fragments subsequently resulting in apoptotic cell death and enhance the expression of the autophagy-promoting protein Beclin-1 expression leading to autophagy [5]. ROS accumulation leading to subsequent autophagy and apoptosis has been reported in the HCC [11]. The use of anti-inflammatory herbal medicine blocked the activation and translocation of NF-κB by suppressing the upstream kinases including Akt (protein kinase B), p85/phosphoinositide-3-kinase, and mitogen activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) [12]. Therefore, the therapeutic strategy for inhibiting CYP2E1-mediated ROS production and p85/MAPK (ERK1/2)/NF-κB-mediated inflammatory signaling protects livers against DEN-induced injury.
Antrodia cinnamomea (formerly named Antrodia camphorata), a precious, host-specific brown-rot fungus that has been used as a folk medicine in Taiwan for centuries is known to have diverse bioactive compounds with potent pharmaceutical activity by the fruiting bodies and liquid cultured mycelium. It has been widely used
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to treated cancer and inflammation, and reported to possess antioxidative, vasorelaxative, anti-inflammatory, anti-angiogenic, hepatoprotective, and anti-hepatitis B virus effects [13-20]. These reports suggest potential pharmaceutical applications for A. cinnamomea. However, A. cinnamomea can only grow on C.
kanehirai Hayata, an endangered species native to Taiwan [13] and it grows at an extremely slow rate. Although laboratory culture systems can easily produce massive amounts of A. cinnamomea mycelium, certain specific and medical compounds/metabolites are deficient in the artificial cultured mycelium. Furthermore, it is difficult to induce fruiting body formation [21,22]. Recently, a technique using basswood-cultivated A. cinnamomea successfully obtained massive production of fruiting bodies with high content of active triterpenoids like Antcin K (AC) and Antcin C [20]. In this study, we determined the potential effects and mechanisms of water extract (ACW) and its novel and active component AC from the fruiting bodies of A. cinnamomea on DEN-induced inflammation, fibrosis and carcinogenesis in the rat livers.
Traditional Chinese herbal medicine has been widely used in modern medicine for health promotion, disease prevention and treatment. These include products made from fungi, such as Monascus spp., and grass crops, such as adlay (Cois lachrymal-jobi L. var. ma-yuen Stapf; also known as Chinese pearl barley and soft-shelled Job’s tears). Products of fermented Monascus spp. (e.g., anka and red koji) were first mentioned in the ancient Chinese pharmacopoeia, Pen-Chow-Kang-Mu (Systematic Pharmacopoeia ) by Li, S. C. in 1596, and are widely used as a Chinese cuisine [38-42] for its metabolic products, including monacolin K, γ-aminobutyric acid, dimerumic acid, and polyketide pigments and so on. The major metabolic product from fermented Monascus species is monacolin K (MK), which is known to
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have hypocholesterolemic, anti-fibrosis, anti-inflammatory, antioxidant, and anti-apoptosis properties [43]. Adlay is widely and popularly planted in Taiwan, China, and Japan. It has a high nutritional value and is effective in the treatment of rheumatism and neuralgia as well as anti-inflammatory, antioxidant, anti-tumeric, and anti-helmintic properties [44,45].
Excess production of reactive oxygen species (ROS) may contribute to abnormal signal transduction or cellular dysfunction, initiating an oxidative stress cascade that leads to ICAM-1 mediated endothelial dysfunction and thrombosis formation [46,47]. Thrombus formation is a highly dynamic process that is mediated by proteins of the coagulation cascade, the subendothelial matrix as well as surface adhesion proteins on platelets, leukocytes and endothelial cells. In the pathological condition of thrombosis, oxidative stress or increased ROS is associated with impaired nitric oxide (NO) bioavailability and endothelial dysfunction, and contributes to the pathogenesis of acute vascular syndromes by predisposing to plaque rupture and intravascular thrombosis [46,47]. A dominant mechanisms of impaired vascular NO bioavailability relates to its oxidative inactivation by O2−•. A central feature of impaired endothelial function is the presence of ROS manifested by oxidized low-density lipoprotein in hypercholesterolemia, glycoxidation products in hyperglycemia, redox-active compounds in tobacco smoke, and lipid peroxides in hyperhomocysteinemia [46]. Oxidized lipids can also be generated by metal-dependent Fenton oxidation; enzyme-catalyzed oxidation by lipoxygenase or reaction with HOCl generated by myeloperoxidase; cell-dependent oxidation via a diversity of O2−• and H2O2-generating oxidases; and oxidation by NO-derived reactive nitrogen species such as •NO2, nitryl chloride (NO2Cl), and peroxynitrite [46,47]. The improvement of endothelial function by decreasing oxidative stress and
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inflammation would attenuate endothelial progenitor cell apoptosis and thrombosis formation [43]. We have demonstrated that inoculating cooked adlay with Monascus spp. produces monascus adlay (MA) containing both functional and active components [48]. MA extracts including rich MK and total phenol contents display higher antioxidant activity, reducing power, scavenging and chelating abilities than uninoculated adlay products [42,48]. MA and MK can depress oxidative stress evoked endoplasmic reticulum stress, apoptosis, autophagy and pyroptosis [48]. MK or lovastatin can inhibit urotensin enhanced expression of VCAM-1 and ICAM-1 by modulating the Rho activation, and NF-kB inhibitors [49]. In addition, phenolic components from adlay inhibit the release and secretion of inflammatory mediators/cytokines [50,51] and decrease O2-. production/generation [52]. However, the anti-thrombotic effect of MA has never been explored. We therefore explored whether dietary MA through its active component, MK, enhances antioxidant, anti-inflammatory, anti-endoplasmic reticulum stress and anti-adhesive mechanisms to counteracting oxidative stress-induced cardiovascular diseases, like thrombosis, in our FeCl3-induced thrombosis.