• Archives of Pharmacal Research
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• v.24 no.2
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• pp.126-135
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• 2001

Quinacrine (QU), a phospholipase-A2 (PLA-2) inhibitor has been used clinically as a chemotherapeutic adjuvant. To understand the mechanisms leading to its chemotherapeutic effect, we have investigated QU-induced apoptotic signaling pathways in human cervical squamous carcinoma HeLa cells. In this study, we found that QU induced cytochrome c-dependent apoptotic signaling. The release of pro-apoptotic cytochrome c was QU concentration- and time-dependent, and preceded activation of caspase-9 and -3. Flow cytometric FACScan analysis using fluorescence intensities of $DiOC_6$/ demonstrated that QU-induced cytochrome c release was independent of mitochondrial permeability transition (MPT), since the concentrations of QU that induced cytochrome c release did not alter mitochondrial membrane potential (${\blacktriangle}{\Psi}_m$). Moreover, kinetic analysis of caspase activities showed that cytochrome c release led to the activation of caspase-9 and downstream death effector caspase-3, Caspase-3 inhibitor (Ac-DEVD-CHO) partially blocked QU-induced apoptosis, suggesting the importance of caspase-3 in this apoptotic signaling mechanism. Supplementation with arachidonic acid (AA) sustained caspase-3 activation induced by QU. Using inhibitors against cellular arachidonate metabolism of lipooxygenase (Nordihydroxyguaiaretic Acid, NDGA) and cyclooxygenase (5,8,11,14-Eicosatetraynoic Acid, ETYA) demonstrated that QU-induced apoptotic signaling may be dependent on its role as a PLA-2 inhibitor. Interestingly, NDCA attenuated QU-induced cytochrome c release, caspase activity as well as apoptotic cell death. The blockade of cytochrome c release by NDCA was much more effective than that attained with cyclosporin A (CsA), a MPT inhibitor. ETYA was not effective in blocking cytochrome c release, except under very high concentrations. Caspase inhibitor z-VAD blocked the release of cytochrome c suggesting that this signaling event is caspase dependent, and caspase-8 activation may be upstream of the mitochondrial events. In summary, we report that QU induced cytochrome c-dependent apoptotic signaling cascade, which may be dependent on its role as a PLA-2 inhibitor. This apoptotic mechanism induced by QU may contribute to its known chemotherapeutic effects.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.5
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• pp.451-460
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• 2015

Sirtuin 1 (SIRT1) is a mammalian $NAD^+$-dependent protein deacetylase that regulates cellular metabolism and inflammatory response. The organ-specific deletion of SIRT1 induces local inflammation and insulin resistance in dietary and genetic obesity. Macrophage-mediated inflammation contributes to insulin resistance and metabolic syndrome, however, the macrophage-specific SIRT1 function in the context of obesity is largely unknown. C57/BL6 wild type (WT) or myeloid-specific SIRT1 knockout (KO) mice were fed a high-fat diet (HFD) or normal diet (ND) for 12 weeks. Metabolic parameters and markers of hepatic steatosis and inflammation in liver were compared in WT and KO mice. SIRT1 deletion enhanced HFD-induced changes on body and liver weight gain, and increased glucose and insulin resistance. In liver, SIRT1 deletion increased the acetylation, and enhanced HFD-induced nuclear translocation of nuclear factor kappa B (NF-${\kappa}B$), hepatic inflammation and macrophage infiltration. HFD-fed KO mice showed severe hepatic steatosis by activating lipogenic pathway through sterol regulatory element-binding protein 1 (SREBP-1), and hepatic fibrogenesis, as indicated by induction of connective tissue growth factor (CTGF), alpha-smooth muscle actin (${\alpha}$-SMA), and collagen secretion. Myeloid-specific deletion of SIRT1 stimulates obesity-induced inflammation and increases the risk of hepatic fibrosis. Targeted induction of macrophage SIRT1 may be a good therapy for alleviating inflammation-associated metabolic syndrome.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.2
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• pp.247-251
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• 2004

UV radiation exerts various influences in the skin, including photoaging and inflammation (1). The MMPs (Matrix metalloproteinases), which are induced by UV irradiation, can degrade matrix proteins, and these results in a collagen deficiency in photodamaged skin that leads to skin wrinkling. It has been known that the production of PGE$_2$ stimulates MMPs expression, and inhibits procollagen (2). Thus, it is possible that the induction of MMPs and the inhibition of matrix protein synthesis by UV -induced PGE$_2$ may play some role in UV-induced collagen deficiency in photoaged skin. Fructose-1,6-diphosphate (FDP), a glycolytic metabolite, is reported to have cytoprotective effects against ischemia and postischemic reperfusion injury of brain and heart, presumably by augmenting anaerobic carbohydrate metabolism (3). And also, FDP significantly prevent skin aging by decreasing facial winkle compared with vehicle alone after 6 months of use. We studied the mechanism of anti-aging effect of FDP on UVB-irradiated HaCaT keratinocyte model. FDP has protective role in UVB injured keratinocyte by attenuating prostaglandin E$_2$ (PGE$_2$) production and COX-2 expression. And FDP also suppressed UVB-induced MMP-2 expression. Further, to delineate the inhibition of UVB-induced COX-2 and MMPs expression with cell signaling pathways, treatment of FDP to HaCaT keratinocytes resulted in marked inhibition of UVB-induced phosphorylation of ERK1/2, JNK. It also prevents UV induced NFB translocation, which are activated by cellular inflammatory signal. Our results indicate that FDP has protecting effects in UV-injured skin aging by decreasing UVB-induced COX-2 and MMPs expression, which are possibly through blocking UVB-induced signal cascades.

• Journal of Periodontal and Implant Science
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• v.30 no.1
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• pp.39-52
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• 2000

Polypeptide growth factor belong to a class of potent biologic mediator which regulate cell differentiation, proliferation, migration and metabolism. 1,25-dihydroxyvitamin $D_3$ decrease cell proliferation, and stimulate alkaline phosphatase activity which express in osteoblast during cell differentiation period. IGF-I is known to stimulate cell proliferation and differentiation too. 1,25-dihydroxyvitamin $D_3$ is known to increase IGF-I binding sites and IGF binding protein which inhibite the effect of IGF. The purpose of this study is to evaluate potential role of IGF-I as mediator that control the action of 1,25-dihydroxyvitamin $D_3$. MC3T3-E1 cell were seeded $5{\times}10^5/ml$ at 100mm culture plate in ${\alpha}-MEM$ containing 10% fetal bovine serum. After 48 hour incubation period, medium were changed ${\alpha}-MEM$ containing 5% fetal bovine serum. After 24 hours, $10^{-9}M$ 1,25-dihydroxyvitamin $D_3$ added. Total mRNA was extracted at 0, 6, 24, 48, 72 hour. PRPCR method was programed for the detection of IGF-I mRNA. In the both groups of 1,25-dihydroxy vitamin $D_3$ treated and control, alternative splicing form of IGF-I, IGF-IA and IGF-IB were expressed. In the 1,25-dihydroxyvitamin $D_3$ treated group, IGF-I mRNA expression was matained until 24 hour, there after expression was decresed. MC3T3-E1 cell were seeded $2.5{\times}10^4/ml$ at 24well plate in ${\alpha}-MEM$ containing 10% fetal bovine serum. After 48 hour incubation period, medium were changed ${\alpha}-MEM$ containing 3% fetal bovine serum. After 24 hours, $10^{-9}M$ 1,25-dihydroxyvitamin $D_3$ and 10 ng/ml IGF-I were added separately or together. Cell were cultured for 1 and 3 days, $2{\mu}Ci/ml\;[^3H]$ -thymidine was added for the last 24h of culture of each days. ${[^3H]}$-thymidine incorporation in to DNA was measured and expressed counter per minute(CPM). DNA synthetic activity was significantly decreased by 1,25-dihydroxyvitamin $D_3$ both at 1 day and 3 day, and in the combination group of 1,25-dihydroxyvitamin $D_3$ and IGF-I, DNA synthetic activity was also decreased both at 1 day and 3 days. IGF-I did not affect the DNA synthetic activity compared to control group both at 1 day and 3 day. From the above results, 1,25-dihydroxyvitamin $D_3$ was potent inhibitor of cell proliferaton in MC3T3-E1 cells. It assumed that the effect of 1,25-dihydroxyvitamin $D_3$ on osteoblast proliferation may be mediated in part by decreased level of IGF-I.

• Reproductive and Developmental Biology
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• v.33 no.3
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• pp.163-169
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• 2009

Many biological systems are regulated by an intricate set of feedback loops that oscillate with a circadian rhythm of roughly 24 h. This circadian clock mediates an increase in body temperature, heart rate, blood pressure, and cortisol secretion early in the day. Recent studies have shown changes in the amplitude of the circadian clock in the hearts and livers of streptozotocin (STZ)-treated rats. It is therefore important to examine the relationships between circadian clock genes and growth factors and their effects on diabetic phenomena in animal models as well as in human patients. In this study, we sought to determine whether diurnal variation in organ development and the regulation of metabolism, including growth and development during the juvenile period in rats, exists as a mechanism for anticipating and responding to the environment. Also, we examined the relationship between changes in growth factor expression in the liver and clock-controlled protein synthesis and turnover, which are important in cellular growth. Specifically, we assessed the expression patterns of several clock genes, including Per1, Per2, Clock, Bmal1, Cry1 and Cry2 and growth factors such as insulin-like growth factor (IGF)-1 and -2 and transforming growth factor (TGF)-${\beta}1$ in rats with STZ-induced diabetes. Growth factor and clock gene expression in the liver at 1 week post-induction was clearly increased compared to the level in control rats. In contrast, the expression patterns of the genes were similar to those observed after 5 weeks in the STZ-treated rats. The increase in gene expression is likely a compensatory change in response to the obstruction of insulin function during the initial phase of induction. However, as the period of induction was extended, the expression of the compensatory genes decreased to the control level. This is likely the result of decreased insulin secretion due to the destruction of beta cells in the pancreas by STZ.

• Journal of Life Science
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• v.26 no.7
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• pp.758-763
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• 2016

Fatty acid transporters are key mediators of skeletal muscle lipid metabolism. Several protein groups have been implicated in cellular long-chain fatty acid uptake or oxidation, including fatty acid transporter proteins (FATPs), the plasma membrane fatty acid-binding protein (FABPpm), and the fatty acid translocase (FAT/CD36). FAT/CD36 is highly expressed in skeletal muscle and known to be regulated by various factors such as exercise and hormones. Insulin-like growth factor-I (IGF-I) is a well-known regulator of skeletal muscle cells. However, it has not been studied whether there is any interaction between IGF-I and FAT/CD36 in skeletal muscle cells. In this study, the effects of IGF-I treatment on FAT/CD36 induction were examined. Differentiated C2C12 cells were treated with 20 ng/ml of IGF-I at different time points. Treatment of C2C12 cells with IGF-I resulted in increased FAT/CD36 mRNA and protein expression. After 24 and 48 hr of IGF-I treatment, FAT/CD36 mRNA increased 89% and 24% respectively. The increase of both proteins returned to the control level after 72 hr of IGF-I treatment, suggesting that the FAT/CD36 gene is regulated pretranslationally by IGF-I in skeletal muscle cells. These results suggest that IGF-I can regulate the expression of FAT/CD36 in skeletal muscle cells. In conclusion, IGF-I induces a rapid transcriptional modification of the FAT/CD36 gene in C2C12 skeletal muscle cells and has modulating effects on fatty acid uptake proteins as well as oxidative proteins.

• Molecules and Cells
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• v.28 no.5
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• pp.431-439
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• 2009

Rice Oryza sativa accelerated cell death and resistance 1 (OsACDR1) encodes a putative Raf-like mitogen-activated protein kinase kinase kinase (MAPKKK). We had previously reported upregulation of the OsACDR1 transcript by a range of environmental stimuli involved in eliciting defense-related pathways. Here we apply biochemical, gain and loss-of-function approaches to characterize OsACDR1 function in rice. The OsACDR1 protein showed autophosphorylation and possessed kinase activity. Rice plants overexpressing OsACDR1 exhibited spontaneous hypersensitive response (HR)-like lesions on leaves, upregulation of defense-related marker genes and accumulation of phenolic compounds and secondary metabolites (phytoalexins). These transgenic plants also acquired enhanced resistance to a fungal pathogen (Magnaporthe grisea) and showed inhibition of appressorial penetration on the leaf surface. In contrast, loss-of-function and RNA silenced OsACDR1 rice mutant plants showed downregulation of defense-related marker genes expressions and susceptibility to M. grisea. Furthermore, transient expression of an OsACDR1:GFP fusion protein in rice protoplast and onion epidermal cells revealed its localization to the nucleus. These results indicate that OsACDR1 plays an important role in the positive regulation of disease resistance in rice.

• Journal of Yeungnam Medical Science
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• v.22 no.2
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• pp.221-240
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• 2005

Background: Doxorubicin has proved to be a useful chemotherapeutic agent especially for osteogenic sarcoma. It induces cancer cell death via apoptosis. Materials and Methods: To explore and analyze the changes of gene expression during doxorubicin induced apoptosis on human osteogenic sarcoma, Saos-2 cell, cDNA microarray was performed. After treatment with doxorubicin, total RNA was purified and expressed genes were investigated with a 17k human cDNA microarray. Results: For analysis of the cDNA microarray, the genes were filtered using the sum of the median value of Cy3 and Cy5 signal intensity of greater than 800. Expression of 264 genes was changed by more than 2 fold, and the expression of 35 genes was changed more than 3 fold after treatment with doxorubicin. The genes were primarily related to cell death, cell growth and maintenance, signal transduction, cellular component, transport, and metabolism. Conclusion: Treatment with doxorubicin induced expressional change of many genes. Some of the genes might be related with apoptosis directly or indirectly. Further study is now needed to characterize these genes.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.12
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• pp.1801-1808
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• 2019

Objective: As an iconic symbol of Qinghai-Tibetan Plateau and of high altitude, yak are subjected to hypoxic conditions that challenge aerobic metabolism. Matrix metalloproteinases-3 (MMP3) is assumed to be a key target gene of hypoxia-inducible factor-$1{\alpha}$ that function as a master regulator of the cellular response to hypoxia. Therefore, the aim of this investigation was to identify the DNA polymorphism of MMP3 gene in domestic yak and to explore its possible association with high-altitude adaptation. Methods: The single-nucleotide polymorphisms (SNPs) genotyping and mutations scanning at the MMP3 locus were conducted in total of 344 individuals from four domestic Chinese yak breeds resident at different altitudes on the Qinghai-Tibetan Plateau, using high-resolution melting analysis and DNA sequencing techniques. Results: The novel of SNPs rs2381 $A{\rightarrow}G$ and rs4331 $C{\rightarrow}G$ were identified in intron V and intron VII of MMP3, respectively. Frequencies of the GG genotype and the G allele of SNP rs2381 $A{\rightarrow}G$ observed in high-altitude Pali yak were significantly higher than that of the other yak breeds resident at middle or low altitude (p<0.01). No significant difference was mapped for SNP rs4331 $C{\rightarrow}G$ in the yak population (p>0.05). Haplotype GC was the dominant among the 4 yak breeds, and Pearson correlation analysis showed that the frequencies of GC was significantly lower in Ganan (GN), Datong (DT), and Tianzhu white yaks (TZ) compared with Pali (PL) yak. The two SNPs were in moderate linkage disequilibrium in high-altitude yaks (PL) but not in middle-altitude (GN, DT) and low-altitude (TZ) yaks. Conclusion: These results indicate that MMP3 may have been subjected to positive selection in yak, especially that the SNP rs2381 $A{\rightarrow}G$ mutation and GC haplotypes might contribute to adaptation for yak in high-altitude environments.

• The Korea Journal of Herbology
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• v.27 no.6
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• pp.107-114
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• 2012

Objectives : In this study, we investigated the anti-diabetic and anti-inflammatory effects of water extract from leaves of Ligustrum japonicum (WLJ) in db/db mouse. Methods : The db/db mice were treated orally with WLJ (300 mg/kg/day) for 10 weeks to examine the long-term effects on hyperglycemia and glomerular tissue as well as biochemical and functional abnormalities in the kidney. Results : WLJ treatment markedly reduced plasma levels of glucose, triglyceride, creatinine, and systolic blood pressure in diabetic db/db mouse. Treatment of WLJ significantly increased plasma level of high density lipoprotein (HDL)-cholesterol. We also found that overexpressions of vascular cellular adhesion molecule (VCAM)-1 and endothelin (ET)-1 were observed in aortic tissue of db/db mouse, whereas, WLJ suppressed both expression of VCAM-1 and ET-1 in aorta. In renal tissue, overexpressions of ICAM-1 and TGF-${\beta}1$ were found in untreated db/db mouse, however, significantly decreased those levels by WLJ treatment. The insulin immunoreactivity of the pancreatic islets remarkably increased in WLJ treated db/db mouse compared with untreated db/db mouse. Taken together, WLJ treatment ameliorated hyperglycemia and hyperlipidemia via improvement of insulin secretion and lipid metabolism, respectively. Furthermore, WLJ treatment also ameliorated hypertension via inhibition of inflammatory process in vascular and renal tissues. Conclusions : Ligustrum japonicum has an anti-diabetic and anti-inflammatory effects in db/db mouse. Thus, these results suggested a beneficial effect of Ligustrum japonicum in treatment with diabetes and diabetic vasculopathy.