Embelin impact on paraquat‐induced lung injury through suppressing oxidative stress,inflammatory cascade,and MAPK/NF‐κB signaling pathway

The current examination was intended to observe the defensive impacts of embelin against paraquat‐incited lung damage in relationship with its antioxidant and anti‐inflammatory action. Oxidative stress marker, like malondialdehyde (MDA), antioxidative enzymes, for example, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH Px), inflammatory cytokines, such as interleukin‐1β (IL‐1β), tumor necrosis factor‐α, and IL‐6, histological examination, and nuclear factor kappa B/mitogen‐activated protein kinase (NF‐κB/MAPK) gene expression were evaluated in lung tissue. Embelin treatment significantly decreased MDA and increased SOD, CAT, and GSH Px. Embelin significantly reduced levels of inflammatory cytokines in paraquat‐administered and paraquat‐intoxicated rats. In addition, embelin suggestively decreased relative protein expression of nuclear NF‐κB p65, p‐NF‐κBp65, p38 MAPK, and p‐p38 MAPKs in paraquat‐intoxicated rats. The outcomes show the impact of embelin inhibitory action on NF‐κB and MAPK and inflammatory cytokines release, and the decrease of lung tissue damage caused by paraquat.     

Nucleosomal distribution of thymine photodimers following far- and near-ultraviolet irradiation

The nucleosomal distribution of cis-syn cyclobutyl-type thymine photodimers was determined in normal human skin fibroblasts following irradiation with low doses of far-ultraviolet light at 254 nm and nearultraviolet light at 313 nm. The thymine photodimer concentrations were determined by high pressure liquid chromatography in acid hydrolysates of total cellular DNA and of nucleosomal core- and chromatosomal-DNA. The lesion concentrations in linker-DNA were calculated from these data. While thymine photodimers were distributed uniformely following 254 nm irradiation they were enriched by a factor of 2.4 – 4.2 in nucleosomal linker DNA after exposure to 313 nm light.     

Relationship between excision repair and the cytotoxic and mutagenic effect of the ‘anti’ 7,8-diol-9,10-epoxide of benzo[a]pyrene in human cells

The cytotoxic and mutagenic effect of (±)-7β,8α-dihydroxy-9α,10α-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (anti BPDE) in normally excision diploid human cells treated just prior to onset of S was compared with that of cells allowed ～ 16 h for excision repair before onset of S and with that observed in excision-deficient serodema pigmentosum (SP12BE) cells. The cells were synchronized by release from density inhibition of cell replication. DNA synthesis began ～ 22 h after the cells were plated at lower density (i.e., 1.4 × 10⁴ cells/cm²). The frequency of thioguanine-resistant mutants induced in normal cells treated just prior to onset of S was ～ 12- to 16-fold higher than that observed in cells treated in early G₁ or treated in G₀ (confluence) and then plated at lower density. The frequency approximated that expected for XP12BE cells from extrapolation of data obtained at lower doses. The frequency of mutants measured in normal cells treated in exponential growth was also much higher than that in the cells treated in early G₁ or in G₀, No such difference could be seen in XP12BE cells treated in exponential growth or in G₀. In contrast to the mutagenicity data in the normal cells, there was no significant difference in the slope of the survival curve of normal cells treated at various times prior to S phase at low densities. However, normal cells treated even at the onset of S exhibited survival equal to XP12BE cells give a 4- to 5-fold lower dose. The data support the hypothesis that DNA synthesis is the cellular event which converts unexcised DNA lesions into mutations. However, they indicate that S is not the event primarily responsible for translating DNA damage into cell death. Accompanying studies on the rate of excision of anti BPDE adducts from the normal cells during the period priot to S support the conclusions.     

Synthesis,cytotoxicity against human oral cancer KB cells and structure–activity relationship studies of trienone analogues of curcuminoids

A general method for the synthesis of substituted (1E,4E,6E)-1,7-diphenylhepta-1,4,6-trien-3-ones, based on the aldol condensations of substituted 4-phenylbut-3-en-2-ones and substituted 3-phenylacrylaldehydes, was achieved. The natural trienones 4 and 5 have been synthesized by this method, together with the trienone analogues 9–20. These analogues were evaluated for their cytotoxic activity against human oral cancer KB cell line. The structure–activity relationship study has indicated that the analogues with the 1,4,6-trien-3-one function are more potent than the curcuminoid-type function. Analogues with meta-oxygen function on the aromatic rings are more potent than those in the ortho- and para-positions. Free phenolic hydroxy group is more potent than the corresponding methyl ether analogues. Among the potent trienones, compounds 11, 18 and 20 were more active than the anticancer drug ellipticine. All compounds were also evaluated against the non-cancerous Vero cells and it was found that compounds 11, 12 and 17 were much less toxic than curcumin (1); they showed high selectivity indices of 35.46, 33.46 and 31.68, respectively. These analogues are regarded as the potent trienones for anti-oral cancer study.     

Additive effect of alpha-tocopherol and ascorbic acid in combating ethanol-induced hepatic fibrosis

Abstract

Objective

To investigate the efficacy of combined administration of alpha-tocopherol (AT) and ascorbic acid (AA) in reducing ethanol-induced hepatotoxicity.

Methods

Rats were maintained for 90 days and grouped as follows: I – control rats, II – ethanol, III – alpha-tocopherol, IV – ethanol + alpha-tocopherol, V – AA, VI – ethanol + ascorbic acid, VII – alpha-tocopherol + ascorbic acid, VIII – ethanol + alpha-tocopherol + ascorbic acid. At the end of the experimental period, markers of hepatic function, oxidative stress, and the expression of markers of inflammation and fibrosis were assayed.

Results

The markers of hepatic function, lipid peroxidation products, protein carbonyls, and the expression of nuclear factor kappa B, tumor necrosis factor alpha, transforming growth factor beta 1, cytochrome P4502E1, and collagen Type I were elevated after ethanol administration. All these parameters were reduced in the ethanol group administered AT and AA in combination. The activities of antioxidant enzymes which were reduced by ethanol administration were enhanced on combined administration of AT and AA. The reduction in hepatic fibrosis was almost 20% more in AT and AA co-administered group compared with AT and AA alone treated groups.

Discussion

Combined administration of fat soluble AT and water soluble AA was beneficial against ethanol-induced hepatotoxicity. This may be due to their different subcellular localizations.     

NEMO specifically recognizes K63‐linked poly‐ubiquitin chains through a new bipartite ubiquitin‐binding domain

An important property of NEMO, the core element of the IKK complex involved in NF‐κB activation, resides in its ability to specifically recognize poly‐ubiquitin chains. A small domain called NOA/UBAN has been suggested to be responsible for this property. We recently demonstrated that the C‐terminal Zinc Finger (ZF) of NEMO is also able to bind ubiquitin. We show here by ZF swapping and mutagenesis that this represents its only function. While neither NOA nor ZF shows any preference for K63‐linked chains, we demonstrate that together they form a bipartite high‐affinity K63‐specific ubiquitin‐binding domain. A similar domain can be found in two other proteins, Optineurin and ABIN2, and can be freely exchanged with that of NEMO without interfering with its activity. This suggests that the main function of the C‐terminal half of NEMO is to specifically bind K63‐linked poly‐ubiquitin chains. We also demonstrate that the recently described binding of NEMO to linear poly‐ubiquitin chains is dependent on the NOA alone and does not require the presence of the ZF.     

Cytisine attenuates bone loss of ovariectomy mouse by preventing RANKL‐induced osteoclastogenesis

Postmenopausal Osteoporosis (PMOP) is oestrogen withdrawal characterized of much production and activation by osteoclast in the elderly female. Cytisine is a quinolizidine alkaloid that comes from seeds or other plants of the Leguminosae (Fabaceae) family. Cytisine has been shown several potential pharmacological functions. However, its effects on PMOP remain unknown. This study designed to explore whether Cytisine is able to suppress RANKL‐induced osteoclastogenesis and prevent the bone loss induced by oestrogen deficiency in ovariectomized (OVX) mice. In this study, we investigated the effect of Cytisine on RAW 264.7 cells and bone marrow monocytes (BMMs) derived osteoclast culture system in vitro and observed the effect of Cytisine on ovariectomized (OVX) mice model to imitate postmenopausal osteoporosis in vivo. We found that Cytisine inhibited F‐actin ring formation and tartrate‐resistant acid phosphatase (TRAP) staining in dose‐dependent ways, as well as bone resorption by pit formation assays. For molecular mechanism, Cytisine suppressed RANK‐related trigger RANKL by phosphorylation JNK/ERK/p38‐MAPK, IκBα/p65‐NF‐κB, and PI3K/AKT axis and significantly inhibited these signalling pathways. However, the suppression of PI3K‐AKT‐NFATc1 axis was rescued by AKT activator SC79. Meanwhile, Cytisine inhibited RANKL‐induced RANK‐TRAF6 association and RANKL‐related gene and protein markers such as NFATc1, Cathepsin K, MMP‐9 and TRAP. Our study indicated that Cytisine could suppress bone loss in OVX mouse through inhibited osteoclastogenesis. All data provide the evidence that Cytisine may be a promising agent in the treatment of osteoclast‐related diseases such as osteoporosis.     

Gastrodin relieves inflammation injury induced by lipopolysaccharides in MRC‐5 cells by up‐regulation of miR‐103

The beneficial function of gastrodin towards many inflammatory diseases has been identified. This study designed to see the influence of gastrodin in a cell model of chronic obstructive pulmonary disease (COPD). MRC‐5 cells were treated by LPS, before which gastrodin was administrated. The effects of gastrodin were evaluated by conducting CCK‐8, FITC‐PI double staining, Western blot, qRT‐PCR and ELISA. Besides this, the downstream effector and signalling were studied to decode how gastrodin exerted its function. And dual‐luciferase assay was used to detect the targeting link between miR‐103 and lipoprotein receptor‐related protein 1 (LRP1). LPS induced apoptosis and the release of MCP‐1, IL‐6 and TNF‐α in MRC‐5 cells. Pre‐treating MRC‐5 cells with gastrodin attenuated LPS‐induced cell damage. Meanwhile, p38/JNK and NF‐κB pathways induced by LPS were repressed by gastrodin. miR‐103 expression was elevated by gastrodin. Further, the protective functions of gastrodin were attenuated by miR‐103 silencing. And LRP1 was a target of miR‐103 and negatively regulated by miR‐103. The in vitro data illustrated the protective function of gastrodin in LPS‐injured MRC‐5 cells. Gastrodin exerted its function possibly by up‐regulating miR‐103 and modulating p38/JNK and NF‐κB pathways.     

Hic‐5 deficiency protects cerulein‐induced chronic pancreatitis via down‐regulation of the NF‐κB (p65)/IL‐6 signalling pathway

Chronic pancreatitis (CP), characterized by pancreatic fibrosis, is a recurrent, progressive and irreversible disease. Activation of the pancreatic stellate cells (PSCs) is considered a core event in pancreatic fibrosis. In this study, we investigated the role of hydrogen peroxide‐inducible clone‐5 (Hic‐5) in CP. Analysis of the human pancreatic tissue samples revealed that Hic‐5 was overexpressed in patients with CP and was extremely low in healthy pancreas. Hic‐5 was significant up‐regulated in the activated primary PSCs independently from transforming growth factor beta stimulation. CP induced by cerulein injection was ameliorated in Hic‐5 knockout (KO) mice, as shown by staining of tissue level. Simultaneously, the activation ability of the primary PSCs from Hic‐5 KO mice was significantly attenuated. We also found that the Hic‐5 up‐regulation by cerulein activated the NF‐κB (p65)/IL‐6 signalling pathway and regulated the downstream extracellular matrix (ECM) genes such as α‐SMA and Col1a1. Therefore, we determined whether suppressing NF‐κB/p65 alleviated CP by treating mice with the NF‐κB/p65 inhibitor triptolide in the cerulein‐induced CP model and found that pancreatic fibrosis was alleviated by NF‐κB/p65 inhibition. These findings provide evidence for Hic‐5 as a therapeutic target that plays a crucial role in regulating PSCs activation and pancreatic fibrosis.