The mechanism of 3,5,2',4'-tetrahydroxychalcone on lowing urate level is still unknown. Here we investigated the effects of 3,5,2',4'-tetrahydroxychalcone on urate levels, xanthine oxidase/xanthine dehydrogenase (XOD/XDH) activities in hypoxanthine-induced hyperuricemic mice, as well as the effects of 3,5,2',4'-tetrahydroxychalcone on the mRNA expression levels and content of phosphoribosyl pyrophosphate synthetase (PRPS), phosphoribosyl pyrophosphate amidotransferase (PRPPAT) and hypoxanthine-guanine phosphoribosyl transferase (HGPRT). Our results demonstrated that 3,5,2',4'-tetrahydroxychalcone (1.0, 2.0, and 4.0 mg/kg) reduced the uric acid levels in serum of the hyperuricemic mice in dose-and time-dependent manners. The activities of XOD/XDH in serum and liver were also significantly inhibited by 3,5,2',4'-tetrahydroxychalcone; In addition, 3,5,2',4'-tetrahydroxychalcone decreased the mRNA expression of HGPRT in brain and content of PRPS and PRPPAT in liver. These findings demonstrated that 3,5,2',4'-tetrahydroxychalcone suppresses uric acid production by affecting the critical enzymes, XOD/XDH, PRPS, PRPPAT and HGPRT in purine nucleotide metabolism.
Melanoma is one of the most aggressive skin cancers with an increasing rate of morbidity. Umbilicaria esculenta is an edible lichen and its main component of extracts-polysaccharide (PUE) has shown significant antitumor effects in a variety of cancer types such as stomach adenocarcinoma. However, whether it has an anti-melanoma effect and the underlying mechanism has not been revealed. In this article, we showed that PUE extracted from Umbilicaria esculenta could inhibit the growth of A875 and A375 melanoma cells but without obvious toxicity to normal vascular endothelial cells. The generation of reactive oxygen species (ROS) in A875 cells was significantly elevated when treated with PUE for 24h. In addition, the expression of caspase-3 and -9 also increased as compared to the controlled group which resulted in the apoptosis of A875 melanoma cells. In the meantime, when pre-treated with N-acetylcysteine (NAC), the ROS scavenger, PUE induced apoptosis and cell death could be reversed via suppression of elevated generation of ROS and ROS-mediated caspase-9 expression. In summary, our study demonstrated that PUE extracts from Umbilicaria esculenta have a potent anti-melanoma effect through the induction of ROS and caspases-3 and -9. It could provide a promising strategy of melanoma therapy with the components from the extracts of natural and edible plants such as lichen Umbilicaria esculenta.
Chelerythrine (CHE) is a type of benzophenanthridine alkaloid found in many herbs and is also the main alkaloid constituent of Toddalia asiatica (L.) LAM. It has been proven to have various activities including antitumor, antifungal, anti-inflammatory and anti-parasitic effects. We have previously demonstrated that CHE can inhibit proliferation and promote apoptosis in human hepatocellular carcinoma (HCC) cells. However, the effect of CHE on the metastasis of HCC and its related molecular mechanisms have yet to be validated. In this study, we investigated the effects of CHE on the migration and invasion of the HCC cell line Hep3B. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), wounding healing, transwell migration and invasion assays and cytoskeleton staining demonstrated that CHE could inhibit the migration and invasion of Hep3B cells in a dose-dependent manner with change of cell structure. RNA interference studies made a knockdown of matrix metalloproteinase (MMP)-2/9 respectively in Hep3B cells. And the results of wounding healing and transwell invasion assay with the treatment of small interfering RNA (siRNA) investigated that MMP-2/9 are positively associated with Hep3B cell metastasis. The results of enzyme-linked immunosorbent assay (ELISA), Western blotting and quantitative RT-PCR showed that CHE suppressed the expression of MMP-2/9 at both mRNA and protein levels. CHE also exhibited an inhibitory effect on the phosphorylation of Focal adhesion kinase (FAK), phosphatidylinositol 3-kinase (PI3K), Akt, mammalian target of rapamycin (mTOR), c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinases (ERK) and p38. In summary, on Hep3B cells, CHE could change the cell cytoskeletal structures through reducing the expression of p-FAK and inhibit the metastasis of Hep3B cells by downregulating the expression of MMP-2/9 mainly through PI3K/Akt/mTOR signaling pathway.
Maintaining a certain level of hydrogen sulfide (H2S) in ischemia-reperfusion (I/R) is essential for limiting injury to the liver. Exogenous H2S exerts protective effects against this injury, but the mechanisms remain unclear. Liver injury was induced in Wistar rats undergoing hepatic I/R for 30min, followed by a 3-h reperfusion. Administration of GYY4137 (a slow-releasing H2S donor) significantly attenuated the severity of liver injury and was reflected by reduced inflammatory cytokine production and cell apoptosis, the levels of which were elevated by I/R, while DL-propargylglycine (PAG, an inhibitor of cystathionine gamma-lyase [CSE]) aggravated liver injury. Delivery of GYY4137 significantly elevated the plasma levels of H2S and upregulated the expression of microRNA-21 (miR-21), leading to the activation of the Akt pathway, in rat livers subjected to I/R. To further investigate the protective mechanisms of H2S during liver I/R injury, we established a cell model of hypoxia/reoxygenation (H/R) by incubating Buffalo rat liver (BRL) cells under hypoxia for 4h followed by normoxia for 10 h. The regulatory effect of miR-21 on the Akt pathway by downregulating phosphatase and tensin homolog (PTEN) was validated by luciferase assays. Incubation of sodium hydrosulfide (NaHS), an H2S donor, increased the expression of miR-21, attenuated the reduced cell viability and the increased apoptosis by H/R, in BRL cells. Anti-miR-21 abolished the protective effects of NaHS by inactivating the Akt pathway. In conclusion, the present results indicate the activation of the Akt pathway regulated by miR-21 participates in the protective effects of H2S against I/R-induced liver injury.
As a traditional herbal medicine, the fruits of Psoralea eorylifolia L. (Fructus Psoraleae (FP)) have been widely used for the treatment of various skin diseases for hundred years. Recently, the emerging FP induced toxic effects, especially hepatotoxicity, in clinic are getting the public's attention. However, its exact toxic components and mechanisms underlying remain unclear. Bavachin, one of flavonoids in FP, has been documented as a hepatotoxic substance, and the present study aimed to determine the toxicity caused by bavachin and the possible toxic mechanisms involved using human hepatocellular carcinoma (HepG2) cells. Our results showed that bavachin could significantly inhibited cell proliferation and trigger the endoplasmic reticulum (ER) stress in a dose dependent manner. Downregulating ER stress using tauroursodeoxycholic acid (TUDCA) obvious attenuated bavachin-triggerd cell apoptosis. Then, small interfering RNA (siRNA) knock-down of Mitofusion2 (Mfn2) resulted in a remarkable aggravation of ER stress through the inhibition of the phosphorylation of protein kinase B (Akt). Additionally, suppression of reactive oxygen species (ROS) by ROS Scavenger (N-acetyl-l-cystein (NAC)) also reduced bavachin-induced ER stress. Taken together, our study demonstrated that bavachin-induced ER stress caused cell apoptosis by Mfn2-Akt pathway, and that ROS may participate upstream in this mechanism. Here, we not only provide a new understanding of ROS/Mfn2/Akt pathway in bavachin-induced cytotoxicity via the ER stress, but also identify a new specific intervention to prevent FP-induced hepatotoxicity in the future.
Nonsteroidal anti-inflammatory drugs (NSAIDs) are likely to be used concomitantly with acyclovir or valacyclovir in clinical practice, but the study on the safety of such combinations was seldom reported. The objective of the study was to investigate reports of acute kidney injury (AKI) events associated with the concomitant use of oral acyclovir or valacyclovir with an NSAID by using the United States Food and Drug Administration (FDA) Adverse Event Reporting System (AERS) database between January 2004 and June 2012. The frequency of AKI events in patients while simultaneously taking either acyclovir or valacyclovir and an NSAID was compared using the Chi-square test. The effect of concomitant use of acyclovir or valacyclovir and individual NSAIDs on AKI was analyzed by the reporting odds ratio (ROR). The results showed that AKI was reported as the adverse event in 8.6% of the 10923 patients taking valacyclovir compared with 8.7% of the 2556 patients taking acyclovir (p=NS). However, AKI was significantly more frequently reported in patients simultaneously taking valacyclovir and an NSAID (19.4%) than in patients simultaneously taking acyclovir and an NSAID (10.5%) (p<0.01). The results also suggested that increased risk of AKI was likely associated with the concomitant use of valacyclovir and some NSAIDs such as loxoprofen, diclofenac, etodolac, ketorolac, piroxicam or lornoxicam. The case series from the AERS indicated that compared with acyclovir, valacyclovir is more likely to be affected by NSAIDs, and the concomitant use of valacyclovir with some NSAIDs might be associated with increased risk of AKI. The drug interactions with this specific combination of medications are worth exploring further.
Patients with Alzheimer's disease (AD) always have cognitive impairments. In this study we investigated whether 6-chloro-7,8-dihydroxy-3-methyl-1-(3-methylphenyl)-2,3,4,5-tetrahydro-1H-3-benzazepine (SKF83959) has improvements on cognitive dysfunction. The scopolamine model of dementia was used to investigate the anti-amnesic activities of SKF83959, and then, Western blotting and pharmacological inhibitor were used to assay the anti-amnesic mechanisms of SKF83959. It was found that SKF83959 administration significantly improved the scopolamine-induced memory impairments in the passive avoidance task, Y-maze test, and Morris water maze task. Moreover, SKF83959 treatment significantly antagonized the down-regulating effects of scopolamine on brain-derived neurotrophic factor (BDNF) signaling cascade in the hippocampus, but not cortex. Importantly, the usage of K252a, a selective inhibitor of tyrosine kinase B (TrkB), significantly attenuated the protective effects of SKF83959 in the scopolamine model. Collectively, this study shows that SKF83959 has beneficial effects in the scopolamine model of dementia by modulation of hippocampal BDNF signaling, implying a novel and potential therapeutic agent for treating dementia in AD.
Psoriasis is a chronic inflammatory skin disease characterized by red, scaly and raised plaques. Thus far, T-cell infiltration is one of the most prominent pathogenic triggers, however, the exact molecular mechanisms underlying psoriasis have not been clearly established. Sphingolipid sphingosine-1-phosphate (SW) is a lysophospholipid regulator modulating a variety of immune cell trafficking via interactions with its cognate receptors, S1P(1-5) . Activation of S1P signaling has recently emerged as a novel therapeutic avenue for psoriasis treatment. Here, we test a newly developed selective S1P, modulator, Sy1930, in four different psoriasis animal models. Our data reveals that oral administration of Sy1930 can induce strong anti-proliferative and anti-inflammatory effects. Specifically, Sy1930 decreases the pathological thickening of back skin induced by sodium lauryl sulfate (SLS), inhibits the proliferation of basal cells in a vaginal epithelium model and increases the granular layer scales in a mouse tail assay. Moreover, Sy1930 can ameliorate the parakeratosis and acanthosis as well as improve granular layer composition and decrease the thickening of epidermis in a propranolol-induced guinea pig psoriasis model. Therefore, we demonstrate that Sy1930 is a promising candidate for psoriasis therapy in clinical.
Ginsenoside-Rg1 (G-Rg1) is an agent isolated from Panax ginseng that exerts anti-fibrotic effects; however, the mechanism is still unclear. Herein, we investigated whether G-Rg1 administration can mitigate or reverse unilateral ureteral obstruction (UUO)-induced renal fibrosis by regulating the Klotho/transforming growth factor (TGF)-beta 1/Smad signaling pathway in rats. Sprague-Dawley male rats were subjected to UUO, and rats in the treatment group were administered G-Rg1 or G-Rg1 plus Klotho short hairpin RNA interference (shRNA), while rats in the control and model groups were administered vehicle for 14d. Epithelial-mesenchymal transition (EMT) biomarkers and Klotho/TGF-/beta 1 signaling molecules were examined by immunohistochemistry, quantitative real-time PCR and Western blotting. Immunohistochemistry showed that UUO induced increased pro-fibrotic TGF-/beta 1 expression, overexpression of the mesenchymal marker, alpha-smooth muscle actin (alpha-SMA), and suppression of the epithelial marker, E-cadherin. Moreover, Western blotting analysis indicated that UUO promoted TGF-beta 1 and phosphorylated Smad3 (p-Smad3) expression (p<0.01), but blocked Klotho and Smad7 expression (p<0.01). After G-Rg1 administration, the UUO-induced TGF-beta 1 and p-Smad3 expression was suppressed (p<0.01), whereas the reduced Klotho and Smad7 expression was reversed (p<0.05), followed by amelioration of the EMT process. Intriguingly, the G-Rg1 effects were largely abrogated by Klotho knockdown. Furthermore, Klotho expression was upregulated by G-Rg1 treatment at the mRNA and protein levels. Our results suggest that G-Rg1 may be beneficial for ameliorating renal fibrosis by targeting Klotho/TGF-beta 1/Smad signaling in UUO rats.
Previous reports have indicated that isosteviol sodium (STVNa) has neuroprotective effects against acute focal cerebral ischemia in rats; however, the exact underlying mechanisms and ideal treatment paradigm are not known. To find a reasonable method for STVNa administration and to determine its possible therapeutic mechanisms, we characterized the protective effects of single-dose and multiple-dose STVNa in cerebral ischemic/reperfusion (I/R) injury in rats. Single and multiple treatments with 10 mg/kg STVNa were administered intraperitoneally after injury to investigate its neuroprotective effects. Neurobehavioral deficits and infarct volume were assessed 7d after ischemia. Both STVNa treatments reduced infarct volumes, improved neurological behaviors, preserved cellular morphology, enhanced neuronal survival, and suppressed cell apoptosis. Multiple treatments performed better than single treatment. Reactive astrogliosis was apparent at 7d after injury and was significantly inhibited by multiple STVNa treatments but not single treatment. These results indicate that STVNa exerts neuroprotection by different mechanisms in the acute and delayed phases of I/R. Specifically, STVNa neuroprotection in the delayed phase of injury was found to be accompanied with the inhibition of astrogliosis.
All-trans retinoic acid (ATRA) has been proved to protect liver from ischemia/reperfusion (IR) injury, however, its mechanism is still unclear. This study is to investigate the mechanism of effect of ATRA on innate immunity in mice liver IR injury. Before operation, mice were gavaged by ATRA at 15 mg/kg/d for two weeks, and then the liver was underwent 70% ischemia (90 min) and reperfusion (6 h). Liver function was assessed by serum alanine aminotransferase (sALT), serum aspartate aminotransferase (sAST). Real-time PCR and Western blot were to detect the level of mRNA and protein. In vitro, RAW264.7 macrophages were treatment with ATRA (1 mu M) or LE540 (5 mu M,a retinoic acid receptor alpha (RAR alpha) receptor antagonist) before lipopolysaccharide (100 ng/mL) stimulation. In vivo, ATRA protected the liver from IR injury by improving hepatocellular function (sALT and sAST), decreasing cell apoptosis and inhibiting inflammatory response (i.e., the level of toll-like receptor 4, transcription factor nuclear factor-kappa Bp65, interleukin (IL)-1 beta, IL-6, and tumor necrosis factor-alpha). When RAR alpha was blocked by LE540 in RAW264.7 macrophages, the inflammatory cytokines were enhancing, along with a decline of Akt phosphorylation but Forkhead box o (Foxo) 1, compared with the ATRA group. In summary, ATRA regulates in part the innate immunity to protect liver from IR injury by RAR alpha/Akt/Foxo1 pathway.
High level apoptosis induced by spinal cord injury (SCI) evokes serious damage because of the loss and dysfunction of motor neurons. Our previous studies showed that inhibition of autophagy evokes the activation of apoptosis. Interestingly, Baicalein, a medicine with anti-apoptosis activity that is derived from the roots of herb Scutellaria baicalensis, largely induces autophagy by activating phosphatidylinositol 3-kinase (PI3K). In this study, we investigated the effects of intraperitoneal injection of Baicalein on autophagy and apoptosis in SCI mice and evaluated the relationship between autophagy and apoptosis. We demonstrated that Baicalein promoted the functional recovery of motor neurons at 7d after SCI. In addition, Baicalein enhanced neuronal autophagy and the autophagy-related factor PI3K, while inhibiting the p62 protein. Baicalein treatment decreased neuronal apoptosis at 7d after SCI. Moreover, when inhibiting autophagy, apoptosis was upgraded by Baicalein treatment after injury. Thus, Baicalein attenuated SCI by inducing autophagy to reduce apoptosis in neurons potentially via activating PI3K.
Osteosarcoma (OS) is a typical bone cancer, and most frequently used cancer treatments for OS are limited due to severe drug-related toxicities. Wasp venoms contain functional components that may offer pharmaceutical components for the treatment of cancers. This study aimed to isolate and characterize a novel peptide (venom anti-cancer peptide 1, VACP1) derived from the wasp venom of Vespa ducalis SMITH. Toxins from Vespa ducalis crude venom were separated by gel filtration and purified by C18 reverse-phase HPLC. As examined by Edman degradation, the amino acid sequence of VACP1 is AQKWLKYWKADKVKGFGRKIKKIWFG. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays revealed that VACP1 inhibited the cell proliferation of MG-63, U-2 OS and Saos-2 cells. Furthermore, annexin V and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining revealed that VACP1 could induce the apoptosis of OS cell lines. In addition, VACP1 increased the protein levels of cleaved poly ADP-ribose polymerase (PARP), caspase 3, but decreased B-cell lymphoma 2 (Bcl-2). Apoptotic signaling pathway screening in MG-63 cells via an antibody array revealed that VACP1 activated the p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) pathways. The present study demonstrates that VACP1 potently suppressed cell proliferation and induced the cell apoptosis of OS cells by inducing the activation of the p38 MAPK and JNK signaling pathways, suggesting that VACP1 is a promising agent for OS therapy.
Oridonin, the major terpene found in Rabdosia rubescens, is widely used as dietary supplement or therapeutic drug, while the effects of oridonin on CYP450 were still unclear. The pregnane X receptor (PXR) is an important regulatory factor for major drug metabolism enzyme CYPs, and it has been reported to have species-specific differences. Therefore, this study has employed more reliable models PXR-humanized mouse to investigate the influence of oridonin on PXR and downstream metabolism enzyme. Eight-week-old male PXR-humanized mice were treated with oridonin by orally (0, 25, 50, 100, 200 mg/kg) for 15d. The effects of oridonin on major downstream CYPs of PXR were examined at both the mRNA and enzyme activity levels by RT-PCR and HPLC-MS/MS. In general, there was no significant toxic reaction in liver of PXR-humanized mice. The mRNA expression of CYPs and cytochrome P450 oxidoreductase (POR) were increased with oridonin treatment in a dose-dependent manner. CYP2c and CYP3a family catalytic activity were increased significantly in two higher doses groups. These results indicate that oridonin induced the expression and activation of CYP2c and CYP3a family, which might contribute to potential drug drug interactions and appear to be a risk when co-administered with other clinical drugs.
The purpose of this study was to determine the effects of different concentrations of ligustrazine, an extract from Chinese herb, on ketamine requirement for hypnosis and analgesia in mice. In the hypnotic response study, mice were randomly allocated to receive saline or ligustrazine at 10, 20, 40, 80 or 160 mg.kg(-1) by intraperitoneal injection. Ketamine was administrated 15 min after ligustrazine injection. The hypnotic response was determined by assessing loss of the righting reflex (LORR) after ketamine injection. The dose of ketamine was determined by modified Dixon's up-and-down method in each group. In the analgesia study, different doses of ligustrazine were administrated 15min before 50 mg.kg(-1) ketamine injection. The analgesia effects (pain threshold) were determined by heat radiation-induced tail-flick latency and evaluated before ligustrazine administration or 5, 15, 30 and 60 min after ketamine administration. The ED50 [95% confidence interval (CI)] for hypnosis induced by ketamine was 54.1 (44.8, 65.3)mg.kg(-1). Ligustrazine dose-dependently decreased the ED50 for ketamine to induce hypnosis, which was [31.6 (26.2, 38.1)1mg.kg(-1) with the addition of 80 mg.kg(-1) ligustrazine and [27.7 (22.6, 33.7)] mg.kg(-1) with the addition of 160 mg.kg(-1) ligustrazine, respectively (p<0.05). Ligustrazine at 160 mg.kg(-1) also increased pain threshold in the presence of ketamine. Ligustrazine enhanced the hypnotic effect of ketamine in a dose-dependent manner. Ligustrazine at a large dose also increased the analgesic effect of ketamine.