BackgroundDeposition and accumulation of silver nanoparticles (Ag-nps) in the liver have been shown to induce hepatotoxicity in animal studies. The hepatotoxicity may include oxidative stress, abnormalities in energy metabolism, and cell death. Studies have indicated that autophagy is an intracellular event involving balance of energy, nutrients, and turnover of subcellular organelles. The present study was undertaken to test the hypothesis that autophagy plays a role in mediating hepatotoxicity in animal after exposure to Ag-nps. Focus was placed on interrelationship between energy metabolism, autophagy, apoptosis and hepatic dysfunction.MethodsSprague Dawley rats were intraperitoneally injected with Ag-nps (10–30 nm in diameter) at concentration of 500 mg kg-1. All animals were sacrificed on days 1, 4, 7, 10 and 30 after exposure and blood and liver tissues were collected for further studies.ResultsUptake of Ag-nps was quite prompt and not proportional to the blood Ag concentration. Declination of ATP (-64% in days 1) and autophagy (determined by LC3-II protein expression and morphological evaluation) increased and peaked on the first day. The ATP content remained at low level even though the autophagy has been activated. Apoptosis (based on caspase-3 protein expression and TUNEL-positive cells staining) began to rise sigmoidally at days 1 and 4, reached a peak level at day 7, and remained at the same levels during days 7–30 post exposure. Meanwhile, autophagy exhibited a gradual decrease from days 1–10 and the decrease at day 30 was statistically significant as compared to day 0 (sham group). Inflammatory reaction (histopathological evaluation) was found at day 10 and preceded to an advanced degree at day 30 when liver function was impaired.ConclusionsThese results indicate that following Ag-nps administration, autophagy was induced; however, failure to preserve autophagy compounded with energy reduction led to apoptosis and the eventual impairment of liver function. The study provides an in-vivo evidence of hepatotoxicity by continuous exposure of Ag-nps in rats.

Background and Purpose: Increasing evidence suggests systemic inflammationcaused skeletal muscle atrophy as a major clinical feature of cachexia. Triptolide obtained from Tripterygium wilfordii Hook F possesses potent anti-inflammatory and immunosuppressive effects. The present study aims to evaluate the protective effects and molecular mechanisms of triptolide on inflammation-induced skeletal muscle atrophy. Experimental Approach: The effects of triptolide on skeletal muscle atrophy were investigated in LPS-treated C2C12 myotubes and C57BL/6 mice. Protein expressions and mRNA levels were analysed by western blot and qPCR, respectively. Skeletal muscle mass, volume and strength were measured by histological analysis, micro-CT and grip strength, respectively. Locomotor activity was measured using the open field test. KEY RESULTS: Triptolide (10-100 fM) up-regulated protein synthesis signals (IGF-1/p-IGF-1R/IRS-1/p-Akt/p-mTOR) and down-regulated protein degradation signal atrogin-1 in C2C12 myotubes. In LPS (100 ngÁml À1 )-treated C2C12 myotubes, triptolide up-regulated MyHC, IGF-1, p-IGF-1R, IRS-1 and p-Akt. Triptolide also down-regulated ubiquitin-proteasome molecules (n-FoxO3a/atrogin-1/MuRF1), proteasome activity, autophagy-lysosomal molecules (LC3-II/LC3-I and Bnip3) and inflammatory mediators (NF-κB, Cox-2, NLRP3, IL-1β and TNF-α). However, AG1024, an IGF-1R inhibitor, suppressed triptolide-mediated effects on MyHC, myotube diameter, MuRF1 and p62 in LPS-treated C2C12 myotubes. In LPS (1 mgÁkg À1 , i.p.)-challenged mice, triptolide (5 and 20 μgÁkg À1 Áday À1 , i.p.) decreased plasma TNF-α levels and it increased skeletal muscle volume, cross-sectional area of myofibers, weights of the gastrocnemius and tibialis anterior muscles, forelimb grip strength and locomotion.Conclusions and Implications: These findings reveal that triptolide prevented LPS-induced inflammation and skeletal muscle atrophy and have implications for the discovery of novel agents for preventing muscle wasting.

The etiological factors of oral cancer are complex including drinking alcohol, smoking tobacco, betel quid chewing, human papillomavirus infection, and nutritional deficiencies. Understanding the molecular mechanism of oral cancer is vital. The traditional treatment for patients with oral squamous cell carcinoma (e.g., surgery, radiotherapy, and chemotherapy) and targeted molecular therapy still have numerous shortcomings. In recent years, the use of phytochemical factors to prevent or treat cancer has received increasing attention. These phytochemicals have little or no toxicity against healthy tissues and are thus ideal chemopreventive agents. However, phytochemicals usually have low water solubility, low bioavailability, and insufficient targeting which limit therapeutic use. Numerous studies have investigated the development of phytochemical delivery systems to address these problems. The present article provides an overview of oral cancer including the etiological factors, diagnosis, and traditional therapy. Furthermore, the classification, dietary sources, anticancer bioactivity, delivery system improvements, and molecular mechanisms against oral cancer of phytochemicals are also discussed in this review.

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Accumulation of oxidative proteins within mitochondria leads to loss of mitochondrial function, which may lead to age-related degenerative diseases. Mitochondrial antioxidant defense capacity reflects the expression of mitochondrial unfolded protein response (mtUPR)-related proteins. Senescent cells are considered to be less resistant to cellular stress stimuli than exponentially growing cells. In this study, we aimed to investigate the ability of mitochondrial stress response in senescent cells to cope with the accumulation of mitochondrial unfolded proteins induced by hydrogen peroxide (H 2 O 2 ) and to understand the relevant molecular mechanisms. We report here that senescence-associated β-galactosidase (SA-β-gal) and senescence marker protein-30 (SMP-30), commonly used replicative senescence biomarkers, changed remarkably between population doubling (PD) 25 (exponentially growing cells) and PD50 (senescent cells) of MRC-5 fibroblasts. Mitochondrial unfolded proteins were significantly accumulated in H 2 O 2 -treated senescent cells, whereas mtUPR-related molecular chaperones (heat shock protein Hsp60 and Hsp10) and proteases (caseinolytic Clp protease) were not concomitantly elevated in senescent cells. In addition, decreased expression of stromal interacting molecule 1-Orai1-mediated store-operated Ca 2+ entry following an declined intracellular calcium level after 2 mM calcium treatment together with H 2 O 2 addition, implying impairment of calcium influx in senescent MRC-5 during H 2 O 2 -induced injury. These findings suggest that senescent fibroblasts expressed higher vulnerability to H 2 O 2 -induced injury involving the imbalance of calcium homeostasis and impaired mitochondrial nuclear communication. This may Abbreviations: [Ca 2+ ]i, intracellular calcium concentration; C/EBPβ, CAAT/enhancer-binding protein-β; CHOP, C/EBP homologous protein; ClpP, caseinolytic Clp protease; CRAC, Ca 2+ releaseactivated Ca 2+ ; ECL, enhanced chemiluminescence; ER, endoplasmic reticulum; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; H2O2, hydrogen peroxide; Hsp10, heat shock protein 10; Hsp60, heat shock protein 60; JNK, c-Jun N-terminal kinase; mtUPR, mitochondrial unfolded protein response; PBS, phosphate-buffered saline; PD, population doubling; PM, plasma membrane; SA-β-gal, senescence-associated β-galactosidase; SERCA, sarcoendoplasmic reticulum calcium transport ATPase; SMP-30, senescence marker protein-30; SOCE, store-operated Ca 2+ entry; STIM1, stromal interacting molecule 1; TBS, Tris-buffer saline; VDAC, voltage-dependent anion channel; X-Gal, 5-bromo-4-chloro-3-indolyl-beta-D-galactoside.

Background The present study was undertaken to test hypothesis that altered transcription of secretory Phospholipase A2 (sPLA2) gene in rat liver is regulated by CCAAT/enhancer binding protein δ (C/EBPδ), and to assess its relationship to hepatic gluconeogenesis during the progression of sepsis. Methods Sepsis was induced by Cecal Ligation and Puncture (CLP). Experiments were divided into three groups, control, early sepsis (9 h after CLP), and late sepsis (18 h after CLP). Results DNA mobility and super shift assays reveal that C/EBP complexes in the liver consisted of at least three isoforms: C/EBPα, C/EBPβ, and C/EBPδ; and various C/EBP isoforms were capable of interacting with each other. Hepatocyte transfection experiments demonstrate that under normal conditions, binding of C/EBPδ to sPLA2 gene enhanced sPLA2 promoter activity and the binding resulted in an increase in hepatic gluconeogenesis. Under pathological conditions such as sepsis, binding of C/EBPδ to sPLA2 promoter increased during early and late phases of sepsis, and the increases in C/EBPδ binding correlated with increases in sPLA2 mRNA abundance and sPLA2 protein levels. Under otherwise the identical experimental conditions, hepatic gluconeogenesis was reduced during early and late phases of sepsis and the sepsis-induced reductions in liver gluconeogenesis were aggravated by binding of C/EBPδ to sPLA2 gene. Conclusions These results link C/EBPδ binding to altered sPLA2 promoter, and to hepatic gluconeogenesis under normal and pathological conditions. It is suggested that C/EBPδ-sPLA2- hepatic gluconeogenesis may function as a signalling axis affecting glucose homeostasis during the progression of sepsis.