Ferulic acid attenuates non-alcoholic steatohepatitis by reducing oxidative stress and inflammation through inhibition of the ROCK/NF-κB signaling pathways.

Ferulic acid (FA) is a natural polyphenol compound existing in many plants. The purpose of this study was to investigate the effect of FA on non-alcoholic steatohepatitis (NASH) induced by high-cholesterol and high-fat diet (HCHF) and its possible mechanism. Rats were fed HCHF for 12 weeks to establish NASH model. FA improved liver coefficients and had no effect on body weight changes. FA could reduce serum alanine transferase (ALT) and aspartate transferase (AST) activities. FA attenuated the increase of total cholesterol (TC), triglyceride (TG) and low-density lipoprotein (LDL) levels caused by NASH, improved the liver pathological damage induced by NASH, and inhibited the progression of liver fibrosis. FA prevented the production of reactive oxygen species (ROS) and the increase of malondialdehyde (MDA) levels, and attenuated the decrease in superoxide dismutase (SOD) activity. Meanwhile, FA significantly restored the levels of interleukin (IL)-1ß, IL-6 and tumor necrosis factor-α (TNF-α). In addition, we also found that FA inhibited the activity of ROCK and the activation of NF-κB signaling pathway in the liver of NASH rats. Overall, FA has a hepatoprotective anti-oxidative stress and anti-inflammatory effects in NASH rats, and its mechanism may be related to the inhibition of ROCK/NF-κB signaling pathway.

Identification of evodiamine and rutecarpine as novel TMEM16A inhibitors and their inhibitory effects on peristalsis in isolated Guinea-pig ileum.

The transmembrane member 16A (TMEM16A)-encoded Ca2+-activated Cl- channel (CaCC) is expressed in interstitial cells of Cajal (ICCs) and involved in the generation of the slow-wave currents of gastrointestinal (GI) smooth muscles. TMEM16A modulators have been shown to positively or negatively regulate the contraction of gastrointestinal smooth muscle. Therefore, targeting the pharmacological modulation of TMEM16A may represent a novel treatment approach for gastrointestinal dysfunctions such as constipation and diarrhoea. In this study, evodiamine and rutecarpine were extracted from the traditional Chinese medicine Evodia rutaecarpa and identified as novel TMEM16A inhibitors with comparable inhibitory effects. Their effects on intestinal peristalsis were examined. Whole-cell patch clamp results show that evodiamine and rutecarpine inhibited TMEM16A Cl- currents in CHO cells. The half-maximal inhibition values (IC50) of evodiamine and rutecarpine on TMEM16A Cl- currents were 11.8 ± 1.3 µΜ and 9.2 ± 0.4 µM, and the maximal effect values (Emax) were 95.8 ± 5.1% and 99.1 ± 1.6%, respectively. The Lys384, Thr385, and Met524 in TMEM16A are critical for evodiamine and rutecarpine's inhibitory effects. Further functional studies show that both evodiamine and rutecarpine can significantly suppress the peristalsis in isolated guinea-pig ileum. These findings demonstrate that evodiamine and rutecarpine are new TMEM16A inhibitors and support the regulation effect of TMEM16A modulators on gastrointestinal motility.

Mechanisms Underlying the Cardioprotection of YangXinDingJi Capsule against Myocardial Ischemia in Rats.

BACKGROUND: YangXinDingJi (YXDJ) capsule is one of traditional Chinese medicines (TCMs) derived from Zhigancao decoction, which is usually used for the treatment of cardiovascular disease in China. Aim of the Study. Cardiovascular events are one of the leading causes of death worldwide. Myocardial ischemia (MI) severely reduces myocyte longevity and function. The YangXinDingJi (YXDJ) capsule has been used in the treatment of clinical cardiac disease in China. Nevertheless, the underlying cellular mechanisms for the benefits to heart function resulting from the use of this capsule are still unclear. The aim of this study was to evaluate the protective effects of the YXDJ on isoprenaline-induced MI in rats and to clarify its underlying myocardial protective mechanisms based on L-type calcium channels and myocardial contractility. MATERIALS AND METHODS: Rats were randomly divided into five groups with ten rats in each group: (1) control; (2) ISO-induced model; (3) high-dose YXDJ (2.8 g/kg/day intraperitoneally for five days), (4) low-dose YXDJ (1.4 g/kg/day for five days); and (5) verapamil (n = 10 in each group). Isoproterenol (ISO) was injected subcutaneously for two consecutive days to induce the rat model of MI. Heart and biochemical parameters were obtained. The patch-clamp technique was used to observe the regulatory effects of YXDJ on the L-type calcium current (ICa-L) in isolated cardiomyocytes. An IonOptix MyoCam detection system was used to observe the contractility of YXDJ on isolated cardiomyocytes. RESULTS: YXDJ caused a significant improvement in pathological heart morphology and alleviated oxidative stress and inflammatory responses. Exposure to YXDJ caused a decrease in blockade of ICa-L in a concentration-dependent manner. CONCLUSIONS: The results indicate that YXDJ significantly inhibited inflammatory cytokine expressions, oxidative stress, and L-type Ca2+ channels, and decreased contractility in isolated rat cardiomyocytes. These findings may be relevant to the cardioprotective efficacy of YXDJ.

Mechanisms underlying the protective effect of tannic acid against arsenic trioxide­induced cardiotoxicity in rats: Potential involvement of mitochondrial apoptosis.

Arsenic trioxide (ATO) is a frontline chemotherapy drug used in the therapy of acute promyelocytic leukemia. However, the clinical use of ATO is hindered by its cardiotoxicity. The present study aimed to observe the potential effects and underlying mechanisms of tannic acid (TA) against ATO­induced cardiotoxicity. Male rats were intraperitoneally injected with ATO (5 mg/kg/day) to induce cardiotoxicity. TA (20 and 40 mg/kg/day) was administered to evaluate its cardioprotective efficacy against ATO­induced heart injury in rats. Administration of ATO resulted in pathological damage in the heart and increased oxidative stress as well as levels of serum cardiac biomarkers creatine kinase and lactate dehydrogenase and the inflammatory marker NF­κB (p65). Conversely, TA markedly reversed this phenomenon. Additionally, TA treatment caused a notable decrease in the expression levels of cleaved caspase­3/caspase­3, Bax, p53 and Bad, while increasing Bcl­2 expression levels. Notably, the application of TA decreased the expression levels of cytochrome c, second mitochondria­derived activator of caspases and high­temperature requirement A2, which are apoptosis mitochondrial­associated proteins. The present findings indicated that TA protected against ATO­induced cardiotoxicity, which may be associated with oxidative stress, inflammation and mitochondrial apoptosis.

Inhibitory effects of four active components in saffron on human ether-a-go-go-related gene (hERG) K+ currents.

The main active components of saffron are crocin, crocetin, picrocrocin, and safranal. There are many studies on their cardioprotective effects, but their cardiotoxicities have not been reported. The human ether-a-go-go-related gene (hERG) K+ channels are of considerable pharmaceutical interest as the target responsible for acquired long QT syndromes. The aim of this study is to explore the effects of crocin, crocetin, picrocrocin, and safranal on the K+ channels encoded by hERG. The interaction of these components with the rapid delayed rectification of K+ currents (IKr) were studied using the perforated patch recording technique. Crocin and picrocrocin had no significant effects on IKr, but crocetin and safranal inhibited hERG K+ currents in a concentration-dependent manner, with IC50 values of 36.35 µM and 37.86 µM, respectively. The maximum inhibitory effects were 37.74 ± 4.14% and 33.74 ± 4.81%, respectively, and the effects were reversible upon washout. The results demonstrate that crocetin and safranal significantly inhibit hERG K+ current, but crocin and picrocrocin do not. This suggests that crocetin and safranal may increase the risk of cardiac arrhythmias by inhibiting IKr.

Crocetin attenuates the oxidative stress, inflammation and apoptosisin arsenic trioxide-induced nephrotoxic rats: Implication of PI3K/AKT pathway.

Arsenic trioxide (ATO)-induced renal toxicity through oxidative stress and apoptosis restricts the therapeutic action of acute myelogenous leukemia. Crocetin (Crt) possesses antioxidant and antiapoptosis properties, and has certain renal protective effects, but it has not been reported that it has protective effect on renal injury caused by ATO. The current study explored the effects and mechanisms of Crt on kidney damage induced by ATO. Fifty Sprague-Dawley rats were randomly divided into five groups. Adult rats were given Crt concurrently with ATO for 1 week. On the 8th day, rats were killed and blood and kidney tissues were collected. Histopathological changes were measured, and kidneytissues and serum were used to determine renal function and antioxidant enzyme activity. In addition, the protein expression levels of P-PI3K, PI3K, P-AKT, AKT, CytC, Bax, Bcl-2 and Caspase-3 were determined via western blot analysis. Results revealed ATO induced renal morphological alterations and activated serum BUN and CRE. Compared with the control group, ROS, MDA, IL-1ß, TNF-α, protein carbonyls (PC), lipid hydroperoxides (LOOH) and arsenic concentration levels were found to be significantly increased and SOD, CAT, GSH-Px, GSH and total sulphydryl groups (TSH) levels were attenuated in the ATO group. Crt markedly reduced oxidative stress in ATO-induced nephrotoxicity. Further, ATO induced apoptosis by significantly enhancing CytC, Bax and Caspase-3 and inhibiting Bcl-2. Administration with Crt markedly improved the expression of apoptosis factor. Moreover, Crt treatment stimulated the expressions of P-PI3K, PI3K, P-AKT, AKT induced by ATO. This study indicates Crt could prevent renal injury caused by ATO through inhibiting oxidative stress, inflammation and apoptosis, and its mechanism may be related to activation of PI3K/Akt signaling pathway.

Safranal, an active constituent of saffron, ameliorates myocardial ischemia via reduction of oxidative stress and regulation of Ca2+ homeostasis.

Safranal (SFR) is the major constituent of saffron. The purpose of this study was to observe the effect of SFR on myocardial ischemia induced by isoprenaline (ISO) and to explore its possible mechanism. The myocardial ischemia rat model was established by subcutaneous injection of ISO (85 mg/kg/d) on the 8th and 9th day of the experiment. Serum creatine kinase (CK), lactate dehydrogenase (LDH), malondialdehyde (MDA) and superoxide dismutase (SOD) were measured, as were changes in calcium concentration, reactive oxygen species (ROS) and cardiac morphology of the myocardial tissue. The effects of SFR on cell contraction, Ca2+ transient and L-type Ca2+ current (ICa-L) in isolated rat myocardial cells were measured using the Ion Optix detection system and the whole-cell patch-clamp technique. SFR can decrease the activity of serum CK, LDH and MDA, and increase the activity of serum SOD, reduce intracellular calcium concentration and the manufacture of ROS. In addition, SFR can improve changes in heart morphology. SFR can significantly inhibit contraction, Ca2+ transients and ICa-L in isolated ventricular myocytes. SFR has a cardioprotective role in ISO-induced MI rats, and the underling mechanism is related to the inhibition of oxidative stress, myocardial contractility, ICa-L and the regulation of Ca2+ homeostasis.

Tannic acid ameliorates arsenic trioxide-induced nephrotoxicity, contribution of NF-κB and Nrf2 pathways.

BACKGROUND AND PURPOSE: Tannic acid (TA), a group of polyphenolic compounds, has multiple anticancer, antimutagenic, antioxidant and anti-inflammatory activities. However, the effects of TA on arsenic trioxide (ATO)-induced nephrotoxicity are still relatively unknown. This study investigated the protective effects and potential mechanisms of TA on ATO-induced nephrotoxicity in rats. METHODS: Rats were intragastrically administered TA with concurrent ATO infused intraperitoneally over 10 days. Renal morphology changes were observed through light microscopy. The levels of antioxidants and pro-inflammatory factors were measured in the serum and renal tissue, respectively. Further, expression of B-cell lymphoma-2, B-cell lymphoma-extra large, p53, and Bcl-2-associated X protein were measured using an immunohistochemical method. The protein expression of nuclear factor kappa B (NF-κB), nuclear factor-erythroid-2-related factor 2 (Nrf2), and kelch-like ECH-associated protein 1 (Keap1) were measured by Western blot. RESULTS: The data showed that ATO exposure significantly increased the serum nephritic, oxidative stress, apoptosis and inflammatory markers in the renal tissue of rats. Conversely, pretreatment with TA reversed these changes. Furthermore, TA treatment caused a significant decrease in NF-κB expression (P < 0.05), while increasing Nrf2 and Keap1 expressions (P < 0.05). CONCLUSION: TA ameliorates ATO-induced nephrotoxicity, which is related to the inhibition of oxidative stress, inflammation and apoptosis, potentially through the NF-κB/Nrf2 pathway.

Crocin attenuates isoprenaline-induced myocardial fibrosis by targeting TLR4/NF-κB signaling: connecting oxidative stress, inflammation, and apoptosis.

Crocin is isolated from saffron and has multiple activities. There are many reports on its beneficial effects for cardiovascular disease, but crocin's effects on anti-myocardial fibrosis have not yet been reported. This study investigated crocin's effects and potential mechanisms on isoproterenol (ISO)-induced myocardial fibrosis (MF) in mice. Mice were infused intraperitoneally with crocin with concurrent ISO subcutaneous injections over 2 weeks. Electrocardiography, cardiac weight index (CWI), hydroxyproline content, and heart morphology changes were observed. Administration of crocin markedly decreased heart rate, J-point elevation, QRS interval, CWI, and hydroxyproline content in the myocardial tissues, and improved heart pathologic morphology. Versus the control group, the ISO group showed an increase in lactate dehydrogenase and creatine kinase activities and malondialdehyde content. Meanwhile, superoxide dismutase, catalase, and glutathione contents decreased in the ISO group; crocin caused a significant reduction in oxidative stress levels in ISO-induced MF. ISO led to a significant increase in interleukin-1 and -6 and tumor necrosis factor-α in addition to nuclear factor kappa B (NF-κB) (p65) and toll-like receptor (TLR) 4 expressions. Crocin treatment suppressed these inflammatory cytokine expressions. Moreover, crocin treatment caused a significant decrease in connective tissue growth factor and transforming growth factor-ß1 mRNA levels in addition to a decrease in B cell lymphoma-2, Bcl-2-associated X protein, caspase-3, and cleaved caspase-3 expressions. Crocin has a protective effect on ISO-induced MF, which may be associated with the TLR4/NF-κB (p65) signal transduction pathway.

Cardioprotective effects of glycyrrhizic acid involve inhibition of calcium influx via L-type calcium channels and myocardial contraction in rats.

Glycyrrhizic acid (GA) is one of the main active components in licorice and has often been reported to have cardioprotective effects. However, the underlying cellular mechanisms remain unclear. The aim of this study is to verify the protective effects of GA against isoproterenol (ISO)-induced myocardial ischemia injury in rats. Another aim is to explore the cellular mechanisms based on the L-type Ca2+ channel, myocardial cell contraction, and intracellular Ca2+ ([Ca2+]i) transient. The results show that GA reduced the ST segment elevation, decreased the heart rate, prevented ISO-induced QT-interval shortening, improved heart morphology, and decreased the activity of CK and LDH. GA blocked ICa-L in a dose-dependent manner. The concentration for 50% of the maximal effect (EC50) of GA was 145.54 µg/mL, and the maximal inhibition was 47.43 ± 0.75% at 1000 µg/mL. However, GA did not affect the dynamical properties of the Ca2+ channel. GA reversibly reduced the amplitude of cell contraction in a dose-dependent manner and slowed down its deflection and recovery, as well as the [Ca2+]i transient. The data demonstrate that GA inhibits L-type Ca2+ channels, decreases the [Ca2+]i transient, and shows a negative cardiac inotropic effect in the ventricular myocardial cells of adult rats. It also protects the myocardia from ischemia injury induced by ISO.

6-Gingerol, an active pungent component of ginger, inhibits L-type Ca2+ current, contractility, and Ca2+ transients in isolated rat ventricular myocytes.

Ginger has been widely used as a flavor, food, and traditional medicine for centuries. 6-Gingerol (6-Gin) is the active components of ginger and offers some beneficial effects on cardiovascular diseases. Here, the effects of 6-Gin on L-type Ca2+ current (ICa-L), contractility, and the Ca2+ transients of rat cardiomyocytes, were investigated via patch-clamp technique and the Ion Optix system. The 6-Gin decreased the ICa-L of normal and ischemic ventricular myocytes by 58.17 ± 1.05% and 55.22 ± 1.34%, respectively. 6-Gin decreased ICa-L in a concentration-dependent manner with a half-maximal inhibitory concentration (IC50) of 31.25 µmol/L. At 300 µmol/L, 6-Gin reduced the cell shortening by 48.87 ± 5.44% and the transients by 42.5 ± 9.79%. The results indicate that the molecular mechanisms underlying the cardio-protective effects of 6-Gin may because of a decreasing of intracellular Ca2+ via the inhibition of ICa-L and contractility in rat cardiomyocytes.