Protein Kinase C Alpha Expression in Human Hepatocellular Carcinoma

Review Protein kinase C (PKC), which contains ten isozymes with distinct enzymological characteristics and intracellular localization, has been believed to be correlated with tumor proliferation, migration and invasion. A recent study found that the PKCα was significantly expressed in the human hepatocellular carcinoma (HCC), and positively correlated with tumor size, tumor stage and mortality rate. It was also found that PKCα played a critical role in cell proliferation, migration and invasion of the poorly differentiated human hepatoma cell lines (HA22T/VGH and SK-Hep-1). In this review, the PKCα signaling in both down-stream and up-stream pathways in HCC cells was discussed

The Protection of Hepatocyte Cells from the Effects of Oxidative Stress by Treatment with Vitamin E in Conjunction with DTT

We investigated the effect of vitamin E on membrane protein thiols under oxidative stress, which we induced by treating hepatocytes with tert-butyl hydroperoxide (TBH) for 60 mins. Those cells which we pretreated with vitamin E formed fewer blebs (22.3% compared to 60.0% in nonvitamin E-treated cells) and maintained cytosolic calcium concentration and the number of membrane protein thiols instead of showing the usual symptoms in cells undergoing oxidative stress. Dithiothreitol (DTT) also commonly reduces bleb formation in hepatocytes affected by TBH. However, our experiments clearly demonstrate that DTT does not prevent the changes in cytosolic calcium and membrane protein thiols in the blebbing cells. Consequently, we decided to pretreat cells with both DTT and vitamin E and found that the influence of TBH was entirely prevented. These findings may provide us with a new aspect for investigating the mechanism of bleb formation under oxidative stress

Ocimum gratissimum Aqueous Extract Induces Apoptotic Signalling in Lung Adenocarcinoma Cell A549

Ocimum gratissimum (OG) is widely used as a traditional herb for its antibacterial activity in Taiwan. Recently, antitumor effect of OG on breast cancer cell is also reported; however, the effects of OG on human pulmonary adenocarcinoma cell A549 remain unclear. Therefore, we aimed to investigate whether aqueous OG extract (OGE) affects viability of A549 cells and the signals induced by OGE in A549 cells. Cell viability assays revealed that OGE significantly and dose-dependently decreased the viability of A549 cell but not that of BEAS-2B cell. Morphological examination and DAPI staining indicated that OGE induced cell shrinkage and DNA condensation for A549 cells. Further investigation showed that OGE enhanced activation of caspase-3, caspase-9 and caspase-8 and increased protein level of Apaf-1 and Bak, but diminished the level of Bcl-2. Additionally, OGE inhibited the phosphorylation of extracellular signal-regulated kinase (ERK) yet enhanced the phosphorylation of c-Jun N-terminal kinase (JNK) and p38 MAP kinase (p38). In conclusion, our findings indicate that OGE suppressed the cell viability of A549 cells, which may result from the activation of apoptotic signaling and the inhibition of anti-apoptotic signaling, suggesting that OGE might be beneficial to lung carcinoma treatment

Ocimum gratissimum Aqueous Extract Protects H9c2 Myocardiac Cells from H2O2-Induced Cell Apoptosis through Akt Signalling

Increased cell death of cardiomyocyte by oxidative stress is known to cause dysfunction of the heart. O. gratissimum is one of the more well-known medicinal plants among the Ocimum species and widely used in treatment of inflammatory diseases. In this study, we hypothesized that aqueous extract of O. gratissimum leaf (OGE) may protect myocardiac cell H9c2 from oxidative injury by hydrogen peroxide (H2O2). Our results revealed that OGE pretreatment dose-dependently protects H9c2 cells from cell death when exposed to H2O2. Additionally, DNA condensation induced by H2O2 was also reduced by OGE pretreatment, suggesting that Ocimum gratissimum extract may attenuate H2O2-induced chromosome damage. Further investigation showed that OGE pretreatment inhibited H2O2-induced activation of caspase-3 and caspase-9, as well as H2O2-induced upregulation of proapoptotic Apaf-1 and the release of cytosolic cytochrome c, but has little effect on the activation of caspase-8. Additionally, OGE pretreatment significantly upregulated Bcl-2 expression and Akt phosphorylation, and slightly affected the phosphorylation of mitogen-activated protein kinases including p38 MAPK and JNK. Taken together, our findings revealed that Ocimum gratissimum extract effectively inhibited the mitochondrial pathway and upregulated Bcl-2 expression, which may be important in protecting H9c2 cells from H2O2-induced cell death

Second-Hand Smoke–Induced Cardiac Fibrosis Is Related to the Fas Death Receptor Apoptotic Pathway without Mitochondria-Dependent Pathway Involvement in Rats

Exposure to environmental tobacco smoke has been epidemiologically linked to heart disease among nonsmokers. However, the molecular mechanism behind the pathogenesis of cardiac disease is unknown. In this study, we found that Wistar rats, exposed to tobacco cigarette smoke at doses of 5, 10, or 15 cigarettes for 30 min twice a day for 1 month, had a dose-dependently reduced heart weight to body weight ratio and enhanced interstitial fibrosis as identified by histopathologic analysis. The mRNA and activity of matrix metalloprotease-2 (MMP-2), representing the progress of cardiac remodeling, were also elevated in the heart. In addition, we used reverse-transcriptase polymerase chain reaction and Western blotting to demonstrate significantly increased levels of the apoptotic effecter caspase-3 in treated animal hearts. Dose-dependently elevated mRNA and protein levels of Fas, and promoted apoptotic initiator caspase-8 (active form), a molecule of a death-receptor–dependent pathway, coupled with unaltered or decreased levels of cytosolic cytochrome c and the apoptotic initiator caspase-9 (active form), molecules of mitochondria-dependent pathways, may be indicative of cardiac apoptosis, which is Fas death-receptor apoptotic-signaling dependent, but not mitochondria pathway dependent in rats exposed to second-hand smoke (SHS). With regard to the regulation of survival pathway, using dot blotting, we found cardiac insulin-like growth factor-1 (IGF-1) and IGF-1 receptor mRNA levels to be significantly increased, indicating that compensative effects of IGF-1 survival signaling could occur. In conclusion, we found that the effects of SHS on cardiomyocyte are mediated by the Fas death-receptor–dependent apoptotic pathway and might be related to the epidemiologic incidence of cardiac disease of SHS-exposed non-smokers

Ontogenic changes in phototaxis and feeding morphology of the clam shrimp Eulimnadia braueriana Ishikawa, 1895

趨光性會影響生物的分布而型態能顯示其功能，本研究以不同照度的人造光源測試真湖蚌蟲 (Eulimnadia braueriana Ishikawa, 1895) 無節幼體、幼體及成體階段的趨光性，並以光學及掃描式電子顯微鏡觀察其攝食構造的形態發育，以探索此物種對於分布和取食的偏好。雖然蚌蟲在發育過程中外觀會有明顯變化，但過去少有探討其發育過程至成熟期的研究。實驗結果顯示，真湖蚌蟲於無節幼體階段會表現出正趨光性，但進入幼體期之後會轉為負趨光性。形態的轉變也大約在同樣時期，主要攝食構造由第二對觸角和大顎轉為較尾端的胸足、小顎、成熟大顎的組合。其攝食構造大多符合濾食性物種的特徵，但成體在前幾對胸足末端具有較堅固的梳狀構造，推測可能也具有刮食能力。從趨光性的結果可以推斷真湖蚌蟲於無節幼體期白天會游向水面，在有攝食能力後以浮游藻類及懸浮顆粒為食。進入幼體期後，真湖蚌蟲將因負趨光性聚集於水底，攝食方式可能濾食由底層懸浮或刮起的物質。在發育過程中的趨光性變化會造成生物的遷徙，可能可以幫助此物種更均勻分布於棲地中。此外，比較向天池三種共域大型鰓足類成體的形態發現，真湖蚌蟲分別與鵠沼枝額蟲 (Branchinella kugenumaensis Ishikawa, 1895) 及貓眼蚌蟲 (Lynceus biformis Ishikawa, 1895) 有相似形態，可能在食性上有競爭壓力；貓眼蚌蟲和鵠沼枝額蟲間則在形態上有明確差異，推測應有棲位分化現象。Phototaxis influences distribution and morphology is representative of function. While clam shrimps undergo an apparent change in appearance during development, ontogenic studies until maturation were seldom the center of attention. In this study, phototaxis through the nauplius, juvenile and adult stages with artificial lighting of different illuminances were tested and developmental morphology of feeding structures were observed with both light microscopy and SEM to explore their preference for general distribution and food. Results revealed that they first show positive phototaxis at the nauplius stage while changing into negative phototaxis from the juvenile stage on. Morphological change and a posterior shift in the main feeding structures also happen at the juvenile stage. The main feeding structures change from the second antenna and mandibles to the more posterior combination of sophisticated mandibles, maxillae and thoracopods. While the feeding structures mostly fit the description for filter feeding animals, scraping structures have also been found on the first several thoracopod pairs in the adult stage. The results imply that newly hatched E. braueriana nauplii will swim to the water surface during day time and filter feed on planktonic particles once having the ability to feed. Reaching the photo-negative juvenile stage, they may gather at the bottom, likely filtering suspended or scraped up particles as food source from this stage on. Ontogenic change in phototaxis leads to migration which could help this species distribute more even through the habitat, avoiding intraspecific competition. In addition, comparing adult feeding structures with the sympatric large branchiopods Siangtian Pond revealed potential competition for E. braueriana with the other two species, Branchinella kugenumaensis Ishikawa, 1895 and Lynceus biformis Ishikawa, 1895, and suggested resource partitioning between B. kugenumaensis and L. biformis

Perilla frutescens leaf extract inhibits mite major allergen Der p 2-induced gene expression of pro-allergic and pro-inflammatory cytokines in human bronchial epithelial cell BEAS-2B.

Perilla frutescens has been used in traditional medicine for respiratory diseases due to its anti-bacterial and anti-inflammatory activity. This study aimed to investigate effects of Perilla frutescens leaf extract (PFE) on expression of pro-allergic and pro-inflammatory cytokines in airway epithelial cells exposed to mite major allergen Der p 2 (DP2) and the underlying mechanisms. Our results showed that PFE up to 100 µg/mL had no cytotoxic effect on human bronchial epithelial cell BEAS-2B. Further investigations revealed that PFE dose-dependently diminished mRNA expression of pro-allergic cytokine IL-4, IL-5, IL-13 and GM-CSF, as well as pro-inflammatory cytokine IL-6, IL-8 and MCP-1 in BEAS-2B cells treated with DP2. In parallel to mRNA, the DP-2-elevated levels of the tested cytokines were decreased. Further investigation showed that DP2-indued phosphorylation of p38 MAPK (P38) and JNK, but not Erk1/2, was also suppressed by PFE. In addition, PFE elevated cytosolic IκBα level and decreased nuclear NF-κB level in DP2-stimulated BEAS-2B cells. Taken together, these findings revealed that PFE significantly diminished both mRNA expression and protein levels of pro-allergic and pro-inflammatory cytokines in response to DP2 through inhibition of P38/JNK and NK-κB activation. These findings suggest that PFE should be beneficial to alleviate both allergic and inflammatory responses on airway epithelium in response to aeroallergens