• Applied Chemistry for Engineering
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• v.24 no.2
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• pp.155-160
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• 2013

Research on mutant generation and isolation for microalgae yielding enhanced lipid accumulation is an important issue for the production of economic biodiesel. In the present study, ultraviolet (UV-B type) ray induced mutant generation was tried using a photosynthetic microalgae, Nannochloropsis oculata (N. oculata), for the production of biodiesel. The resulting colonies were isolated and further cultured with both liquid and solid state f/2 media. After a few week cultivation, changes of cell growth rate, dry cell weight, and several important intracellular components (chlorophyll, carotenoid, and lipid) were investigated. Two mutants among thousands colonies showed an increased cell growth and high lipid accumulation as compared to those of wild type. It was also observed that the increased cell growth rate is associated with the overexpressed intracellular proteins. However, the mutants showed a decrease in the chlorophyll biosynthesis.

• Food Science of Animal Resources
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• v.30 no.5
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• pp.787-794
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• 2010

Calcium plays a role as a signaling molecule in various cellular events. It has been reported that calcium suppresses adipocyte differentiation only in the early phase of adipogenesis. Herein, we demonstrate that treatment of A23187, a mobilizer of intracellular calcium, on day 4 post adipocyte differentiation could still reduce lipid accumulation in differentiating 3T3-L1 cells for 48 h. In addition, luciferase reporter gene and RT-Q-PCR assays demonstrate that A23187 can selectively inhibit transcriptional activities and expression of PPAR$\gamma$ and LXR$\alpha$, suggesting that A23187 may reduce lipid accumulation in the late phase of adipogenesis via downregulation of PPAR$\gamma$ and LXR$\alpha$ expression and transactivation. Moreover, inhibition of HDAC activity by trichostatin A (TSA) partially blocked A23187-mediated downregulation of transcriptional activities of PPAR$\gamma$ and LXR$\alpha$. Together, our data demonstrate that calcium mobilization inhibits expression and transcriptional activities of PPAR$\gamma$ and LXR$\alpha$, resulting in reduced lipid accumulation in differentiating adipocytes, and thus, mobilization of intracellular calcium in adipocytes may serve as a new preventive and therapeutic approach for obesity.

• Biomedical Science Letters
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• v.11 no.3
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• pp.301-305
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• 2005

MR spectroscopy of intracellularly located $^{133}Cs$ has been used to monitor the uptake of Gd-EOB-DTPA by the isolated rat liver. As shown by ${31}P$ spectroscopy, accumulation of $^{133}Cs$ ions in hepatocytes does not produce detectable effects on the metabolism. The hepatic internalization of Gd-EOB-DTPA was followed by the paramagnetic relaxation enhancement of the intracellular $^{133}Cs$ ions, and confirmed by parallel quantitations of Gd and Cs run by inductively coupled plasma analysis of liver samples and aliquots of perfusate. Two peaks are observed at -22.0 and -23.5 ppm, with respect to the line of the external reference arbitarily set to 0 ppm. Upon rinsing of the extracellular compartment with regular K-H free of CsCl, the high-field resonance disappears within 20min. The intracellular concentration was confirmed by ICP, which gives a $Cs^+$ content of $22.0\pm3.5mM$. The relaxation data significantly underestimate the Gd content, suggesting a potential compartmentation of $Cs^+$ and the contrast agent.

• Archives of Pharmacal Research
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• v.13 no.4
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• pp.298-305
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• 1990

Based on equal number of cells, supplementation of 10$^{-6}$ M cadimium highly simulated the intracellular amylase. GCT, LDH as well as the glucose and erea content of E carotovora var, carotovaro cells. This was coupled with initiation of highly active GOT, CPK as well as accumulation of cholesterol in the cells. Lanthanum was less active and unable to initiate COT or CPK. Nickel was almost without effect though reduced LDH activity without initiating either enzyme or cholesterol production. Similar stiulations and/or initiations were observed, though to variable extents, when the same concentration of the three elements were supplied to E. carotovora var, citullis or E. toxica. The highest yield of amylase, GPT, GGT or glucose was obtained when E. carotovora var. carotovora was supplemented with Cd + Ni. The highest urea level was recorded in Erwinia carotovara var, cirullis, amended with Cd + La.

• Journal of Plant Biology
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• v.19 no.2
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• pp.41-44
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• 1976

Ethylene was found to reverse the direction of gravity-induced lateral auxin transport and to cause an accumulation of auxin in the physically upper sides of horizontally placed pea shoots. The pea shoot displayed a slightly positive (downward) geotropic curvature in the presence of applied ethylene. Golgi bodies were found to be distributed preferentially in the bottom halves of cells as against the top halves following geotropic stimulation, and this pattern of intracellular distribution of dictyosomes was also reversed by ethylene treatment. Intracellular displacement of amyloplsts as a result fo geotropic induction was not reversed by the action of ethylene. In view of a positive correlation between the direction of auxin movement and the displacement patern of dictyosomes, it is suggested that the Golgi bodies are involved in the perception of gravity and/or subsequent redistribution of auxin or differential elongation in geotropism.

• Anatomy and Cell Biology
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• v.57 no.2
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• pp.155-162
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• 2024

Cerebral ischemia is the important cause of worldwide disability and mortality, that is one of the obstruction of blood vessels supplying to the brain. In early stage, glutamate excitotoxicity and high level of intracellular calcium (Ca²⁺) are the major processes which can promote many downstream signaling involving in neuronal death and brain tissue damaging. Moreover, autophagy, the reusing of damaged cell organelles, is affected in early ischemia. Under ischemic conditions, autophagy plays an important role to maintain energy of the brain and its function. In the other hand, over intracellular Ca²⁺ accumulation triggers excessive autophagic process and lysosomal degradation leading to autophagic process impairment which finally induce neuronal death. This article reviews the association between intracellular Ca²⁺ and autophagic process in acute stage of ischemic stroke.

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.349-354
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• 2006

Furaneol, a key aroma compound found in strawberry, pineapple, and processed foodstuffs, has been known to possess various biological activities on animal models. In this study, the antimicrobial effects of furaneol against human pathogenic microorganisms were investigated. The results indicated that furaneol displayed a broad spectrum of antimicrobial activities against Gram-positive and Gram-negative bacteria and fungi without hemolytic activity on human erythrocyte cells. To confirm the antifungal activity of furaneol, we examined the accumulation of intracellular trehalose as a stress response marker on toxic agents and its effect on dimorphic transition of Candida albicans. The results demonstrated that furaneol induced significant accumulation of intracellular trehalose and exerted its antifungal effect by disrupting serum-induced mycelial forms. These results suggest that furaneol could be a therapeutic agent having a broad spectrum of antimicrobial activity on human pathogenic microorganisms.

• Proceedings of the KOSOMBE Conference
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• v.1996 no.05
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• pp.97-99
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• 1996

Intracellular gradients of the free calcium concentration are thought to be critical for the localization of functional responses within a cell. The mechanism of mechanotransduction may be associated with the localized accumulation of calcium stores for shear stress-exposed endothelial cells. The distribution of the calcium stores and the formation of the stress fibers were investigated by the indirect double immunofluorescent staining method with the calreticulin antibody and rhodamine phalloidin under flow condition. The shear stress of steady flow reorganized the cytoskeleton structure including the bundling and translocation to focal contacts. The calcium stores translocated from the cytoplasm to the focal contacting area. Consequently. accumulation of the calcium stores may participate in the shear stress-induced cytoskeleton organization of endothelial cells.

• Korean Journal of Radiology
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• v.23 no.6
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• pp.581-597
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• 2022

Left ventricular (LV) wall thickening, or LV hypertrophy (LVH), is common and occurs in diverse conditions including hypertrophic cardiomyopathy (HCM), hypertensive heart disease, aortic valve stenosis, lysosomal storage disorders, cardiac amyloidosis, mitochondrial cardiomyopathy, sarcoidosis and athlete's heart. Cardiac magnetic resonance (CMR) imaging provides various tissue contrasts and characteristics that reflect histological changes in the myocardium, such as cellular hypertrophy, cardiomyocyte disarray, interstitial fibrosis, extracellular accumulation of insoluble proteins, intracellular accumulation of fat, and intracellular vacuolar changes. Therefore, CMR imaging may be beneficial in establishing a differential diagnosis of LVH. Although various diseases share LV wall thickening as a common feature, the histologic changes that underscore each disease are distinct. This review focuses on CMR multiparametric myocardial analysis, which may provide clues for the differentiation of thickened myocardium based on the histologic features of HCM and its phenocopies.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.2
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• pp.200-206
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• 2014

We investigated the in vitro and in vivo anti-obesity effects of extracts from young Akebia quinata D. leaves, including hot water (AQH) and 80% ethanol (AQE) extracts. The inhibitory effects of AQH and AQE on lipid accumulation in 3T3-L1 cells were examined by Oil Red O staining. Compared to control, lipid accumulation was significantly reduced by 18.3% with the treatment upon AQE at a concentration of $5{\mu}g/mL$. The levels of intracellular triglycerides and free glycerol were also reduced by 52.8% and 9.1% at the same concentration of AQE. The in vivo anti-obesity effect of AQE was evaluated in terms of body and white adipose tissue weights in ICR mice. Experimental groups were divided into the following five groups: normal diet (ND), high fat diet (HFD), high fat diet with 60 mg/kg/day of Orlistat (HFD-RF), high fat diet with 200 mg/kg/day of AQE (HFD-AL), and high fat diet with 600 mg/kg/day of AQE (HFD-AH). Feeding of HFD for eight weeks resulted in significant increases in body weight as well as weight gain compared to the ND group. HFD-AH group showed reduced body weight, weight gain, epididymal white adipose tissue weight, and perirenal white adipose weight as compared to the HFD group. These results indicate that AQE supplementation might have beneficial effects on anti-obesity by inhibiting lipid accumulation.