Pengaruh Konsentrasi Ekstrak Daun Kepel (Stelechocarpus Burahol (Bl) Hook F. & Th.) Terhadap Aktivitas Antioksidan Dan Sifat Fisik Sediaan Krim

This research was aimed to determine the effect of concentrations of Kepel leaves\u27 (Stelechocarpus burahol (BL) Hook f. & Th.)extract to antioxidant activity and physical properties of cream. Kepel leaves\u27 extract were made by infundation method. The antioxidant activity was tested by DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging method. Cream was made in three formulas with variation concentrations of Kepel leaves\u27 extract (2,5; 5,0; 7,5%b/b) using w/o basis. Physical stability parameters tested in this research were homogenity, dispersive power, adhesion, and viscosity. Data were then analyzed statistically by ANOVA One Way and Turkey Test at 95% level of significance. The results showed that concentration of Kepel leaves\u27 extract as an active ingredient cause different color, odor, and viscosity of the cream. The concentrationdifference of Kepel Leaves\u27 extract as an active ingredient was not affected the homogenity, adhesion, and the separation ratio of the cream. The difference concentration was not cause affected daya sebar cream unless the formula II (5.0% w/w) and formula III (7.5% w/w). Increasing concentration of Kepel leaves\u27 extract caused a different antioxidant activity unless the formula II (5.0% w/w) and formula III (7.5% w/w)

Deletion of the <i>trx2</i>⁺ gene enhanced Rst2 transcriptional activity.

<p>(A) The Δ<i>trx1</i> and Δ<i>trx2</i> cells showed H₂O₂-sensitive phenotype. Wild-type, Δ<i>trx1</i> and Δ<i>trx2</i> cells were streaked onto YES plates with or without 3 mM H₂O₂, and cultured at 30°C for 3 days. (B) Deletion of the <i>trx2</i>⁺ gene enhanced Rst2 transcriptional activity. Wild-type and Δ<i>trx2</i> cells harboring the reporter plasmid were cultured and assayed as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0078012#pone-0078012-g001" target="_blank">Figure 1A</a>. (C and D) Deletion of the <i>trx2</i>⁺ gene specifically enhanced Rst2 transcriptional activity. Wild-type, Δ<i>trx2</i>, Δ<i>tpx1</i> and Δ<i>pap1</i> cells harboring the reporter plasmid were cultured and assayed as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0078012#pone-0078012-g001" target="_blank">Figure 1A</a>. Error bars, mean ± S.D. (n ≥ 3).</p

Genome-Wide Screening for Genes Associated with Valproic Acid Sensitivity in Fission Yeast

<div><p>We have been studying the action mechanisms of valproic acid (VPA) in fission yeast <i>Schizosaccharomyces pombe</i> by developing a genetic screen for mutants that show hypersensitivity to VPA. In the present study, we performed a genome-wide screen of 3004 haploid deletion strains and confirmed 148 deletion strains to be VPA sensitive. Of the 148 strains, 93 strains also showed sensitivity to another aliphatic acids HDAC inhibitor, sodium butyrate (SB), and 55 strains showed sensitivity to VPA but not to SB. Interestingly, we found that both VPA and SB treatment induced a marked increase in the transcription activity of Atf1 in wild-type cells. However, in <i>clr6-1</i>, a mutant allele the <i>clr6⁺</i> gene encoding class I HDAC, neither VPA- nor SB induced the activation of Atf1 transcription activity. We also found that VPA, but not SB, caused an increase in cytoplasmic Ca²⁺ level. We further found that the cytoplasmic Ca²⁺ increase was caused by Ca²⁺ influx from extracellular medium via Cch1-Yam8 channel complex. Altogether, our present study indicates that VPA and SB play similar but distinct roles in multiple physiological processes in fission yeast.</p></div

NO may be involved in the activation of Rst2.

<p>(A and B) NO generators activated Rst2 transcriptional activity. Wild-type cells harboring the reporter plasmid were treated with GR or GD in the presence or absence of 125 μM NO generators (SNAP, DEA NONOate or SNP). (C and D) Calboxy-PTIO inhibited Rst2 transcriptional activity upon glucose deprivation. Wild-type cells harboring the reporter plasmid were treated with GD in the presence or absence of calboxy-PTIO (0.125 mM to 1 mM). Error bars, mean ± S.D. (n ≥ 3).</p

NO generator SNAP activated Rst2 transcriptional activity.

<p>(A and B) SNAP enhanced Rst2 transcriptional activity upon glucose deprivation. Wild-type cells harboring the reporter plasmid were assayed in GD media in the presence or absence of SNAP. (C and D) SNAP enhanced Rst2 transcriptional activity under glucose-rich conditions. Wild-type cells harboring the reporter plasmid were assayed in GR media in the presence or absence of SNAP. </p

PKA inhibited Rst2 transcriptional activity.

<p>(A and B) Deletion of the <i>pka1</i>⁺ gene enhanced Rst2 transcriptional activity. The wild-type and Δ<i>pka1</i> cells harboring the reporter plasmid were cultured and assayed as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0078012#pone-0078012-g001" target="_blank">Figure 1A</a>. (C) The effect of cAMP on Rst2 transcriptional activity. The wild-type and Δ<i>pka1</i> cells harboring the reporter plasmid were treated with GD in the presence or absence cAMP (2.5 mM to 10 mM). Error bars, mean ± S.D. (n ≥ 3).</p

Monitoring of Rst2 transcriptional activity in living cells by using the <i>Renilla</i> luciferase reporter assay.

<p>(A) Glucose deprivation induced a marked increase in transcriptional activation. Wild-type cells harboring the reporter plasmid were cultured and assayed as described under “Materials and Methods”. GR (light gray line) indicates that the cells were resuspended in glucose-rich medium (GR). GD (dark gray line) indicates that the cells were resuspended in low glucose medium to induce glucose deprivation (GD). Y-axis values are the ratio of relative light units (RLU) of each sample to that of wild-type cells in GR at 150 minutes. The data shown are representative of multiple experiments. (B) Glucose deprivation-induced transcriptional activation is completely abolished in Δ<i>rst2</i> cells. The Δ<i>rst2</i> cells harboring the reporter plasmid were cultured and assayed as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0078012#pone-0078012-g001" target="_blank">Figure 1A</a>. (C) Rst2 is specifically activated by glucose deprivation. Wild-type cells harboring the reporter plasmid were treated with GR, GD, 1 mM H₂O₂, 300 mM KCl or 1 mM CdCl₂ as indicated. Area under the curve (AUC) is expressed as a percentage of RLU of wild-type cells in GD from 0 to 300 minutes. Error bars, mean ± S.D. (n ≥ 3).</p

VPA and SB increased Atf1 transcriptional activity in a Clr6-dependent manner.

<p>(A) VPA or SB treatment markedly increased Atf1 transcription activity in wild-type cells. The wild-type cells harboring the multicopy plasmid (3XCRE::luc(R2.2) report plasmid) were grown to exponential phase, and assayed as described in Materials and Methods. The luminescence was followed for 5 hours. The data represent the accumulated value ratio of each sample (VPA or SB treatment) to the basal (EMM). Standard deviations are from three independent experiments, and each sample was analyzed in triplicate. Mean±S.D. (n = 6). P<0.05. (B) VPA or SB treatment failed to increase Atf1 transcription activity in <i>clr6-1</i> mutant cells. The experiments were performed as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068738#pone-0068738-g003" target="_blank">Figure 3A</a>, except <i>clr6-1</i> mutant cells were monitored instead of the wild-type cells. Mean±S.D. (n = 6). P<0.01.</p

Strains used in this study.

<p>Strains used in this study.</p

VPA and SB may function as HDAC inhibitor in fission yeast.

<p>(A) The Venn diagrams of VPA- or SB- sensitive strains. The SB-sensitive strains were completely included in VPA-sensitive strains. Of the 148 VPA-sensitive strains, 93 strains also showed sensitivity to SB, the other 55 strains only showed sensitivity to VPA. (B) Immunoblot analysis of histone acetylation. The wild-type cells and <i>clr6-1</i> mutants were cultured in YPD at 27°C for 10 hours to exponential phase. Then the cell extracts were subjected to electrophoresis using 11% polyacrylamide gel and were immunoblotted using Acetyl-histone H4 antibody set (Ac K5; Ac K8; Ac K12) to detect histone H4 acetylation. Endogenous levels of total histone H4 protein was used as a loading control and was immunoblotted using anti-histone H4 antibodies. (C) VPA and SB treatment increased histone H4 acetylation. The exponentially growing wild-type cells were divided into three equal portions. One portion is left without treatment and the other three portions were treated with 4 mM VPA, 60 mM SB or 20 µg/ml TSA for 20 minutes, respectively. Then the protein is extracted and immunoblotted as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068738#pone-0068738-g002" target="_blank">Figure 2A</a>.</p