Stereoisomer-specific ginsenoside 20(S)-Rg3 reverses replicative senescence of human diploid fibroblasts via Akt-mTOR-Sirtuin signaling

Foci of phosphorylated histone H2AX and ATM are the surrogate markers of DNA double strand breaks. We previously reported that the residual foci increased their size after irradiation, which amplifies DNA damage signals. Here, we addressed whether amplification of DNA damage signal is involved in replicative senescence of normal human diploid fibroblasts. Large phosphorylated H2AX foci (>1.5 μm diameter) were specifically detected in presenescent cells. The frequency of cells with large foci was well correlated with that of cells positive for senescence-associatedβ-galactosidase staining. Hypoxic cell culture condition extended replicative life span of normal human fibroblast, and we found that the formation of large foci delayed in those cells. Our immuno-FISH analysis revealed that large foci partially localized at telomeres in senescent cells. Importantly, large foci of phosphorylated H2AX were always colocalized with phosphorylated ATM foci. Furthermore, Ser15-phosphorylated p53 showed colocalization with the large foci. Since the treatment of senescent cells with phosphoinositide 3-kinase inhibitor, wortmannin, suppressed p53 phosphorylation, it is suggested that amplification of DNA damage signaling sustains persistent activation of ATM-p53 pathway, which is essential for replicative senescence.

Download Full-text

Effects of Glucose Restriction on Replicative Senescence of Human Diploid Fibroblasts IMR-90

Cellular Physiology and Biochemistry ◽

10.1159/000350090 ◽

2013 ◽

Vol 31 (4-5) ◽

pp. 718-727 ◽

Cited By ~ 4

Author(s):

Junhua Jin ◽

Tiemei Zhang

Keyword(s):

Replicative Senescence ◽

Diploid Fibroblasts ◽

Human Diploid Fibroblasts ◽

Glucose Restriction

Download Full-text

Features of replicative senescence induced by direct addition of antennapedia-p16INK4A fusion protein to human diploid fibroblasts

FEBS Letters ◽

10.1016/s0014-5793(98)00426-8 ◽

1998 ◽

Vol 427 (2) ◽

pp. 203-208 ◽

Cited By ~ 61

Author(s):

Daishiro Kato ◽

Kazuhiro Miyazawa ◽

Marugarida Ruas ◽

Maria Starborg ◽

Ikuo Wada ◽

...

Keyword(s):

Fusion Protein ◽

Replicative Senescence ◽

Diploid Fibroblasts ◽

Human Diploid Fibroblasts ◽

Direct Addition

Download Full-text

Expression of Senescence-Associated microRNAs and Target Genes in Cellular Aging and Modulation by Tocotrienol-Rich Fraction

Oxidative Medicine and Cellular Longevity ◽

10.1155/2014/725929 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 7

Author(s):

Sharon Gwee Sian Khee ◽

Yasmin Anum Mohd Yusof ◽

Suzana Makpol

Keyword(s):

Cellular Senescence ◽

Target Genes ◽

Replicative Senescence ◽

Primary Cultures ◽

Ectopic Expression ◽

Cellular Aging ◽

Diploid Fibroblasts ◽

Human Diploid Fibroblasts ◽

Tocotrienol Rich Fraction

Emerging evidences highlight the implication of microRNAs as a posttranscriptional regulator in aging. Several senescence-associated microRNAs (SA-miRNAs) are found to be differentially expressed during cellular senescence. However, the role of dietary compounds on SA-miRNAs remains elusive. This study aimed to elucidate the modulatory role of tocotrienol-rich fraction (TRF) on SA-miRNAs (miR-20a, miR-24, miR-34a, miR-106a, and miR-449a) and established target genes of miR-34a (CCND1, CDK4, and SIRT1) during replicative senescence of human diploid fibroblasts (HDFs). Primary cultures of HDFs at young and senescent were incubated with TRF at 0.5 mg/mL. Taqman microRNA assay showed significant upregulation of miR-24 and miR-34a and downregulation of miR-20a and miR-449a in senescent HDFs (P<0.05). TRF reduced miR-34a expression in senescent HDFs and increased miR-20a expression in young HDFs and increased miR-449a expression in both young and senescent HDFs. Our results also demonstrated that ectopic expression of miR-34a reduced the expression of CDK4 significantly (P<0.05). TRF inhibited miR-34a expression thus relieved its inhibition on CDK4 gene expression. No significant change was observed on the expression of CCND1, SIRT1, and miR-34a upstream transcriptional regulator, TP53. In conclusion tocotrienol-rich fraction prevented cellular senescence of human diploid fibroblasts via modulation of SA-miRNAs and target genes expression.

Download Full-text

Induction of replicative senescence by 5-azacytidine: fundamental cell kinetic differences between human diploid fibroblasts and NIH-3T3 cells

Cell Proliferation ◽

10.1111/j.1365-2184.1993.tb00005.x ◽

1993 ◽

Vol 26 (1) ◽

pp. 45-54 ◽

Cited By ~ 18

Author(s):

E. M. Weller ◽

M. Poot ◽

H. Hoehn

Keyword(s):

Replicative Senescence ◽

3T3 Cells ◽

Cell Kinetic ◽

Diploid Fibroblasts ◽

Human Diploid Fibroblasts ◽

Nih 3T3 ◽

Nih 3T3 Cells

Download Full-text

Chlorella vulgaris modulates the expression of senescence-associated genes in replicative senescence of human diploid fibroblasts

Molecular Biology Reports ◽

10.1007/s11033-019-05140-8 ◽

2019 ◽

Vol 47 (1) ◽

pp. 369-379 ◽

Cited By ~ 2

Author(s):

Faizul Jaafar ◽

Lina Wati Durani ◽

Suzana Makpol

Keyword(s):

Chlorella Vulgaris ◽

Replicative Senescence ◽

Diploid Fibroblasts ◽

Human Diploid Fibroblasts ◽

Senescence Associated Genes

Download Full-text

Piper betle L. Modulates Senescence-Associated Genes Expression in Replicative Senescent Human Diploid Fibroblasts

BioMed Research International ◽

10.1155/2017/6894026 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Lina Wati Durani ◽

Shy Cian Khor ◽

Jen Kit Tan ◽

Kien Hui Chua ◽

Yasmin Anum Mohd Yusof ◽

...

Keyword(s):

Replicative Senescence ◽

Piper Betle ◽

Aqueous Extracts ◽

Leaf Extracts ◽

Diploid Fibroblasts ◽

Human Diploid Fibroblasts ◽

Anticancer Effects ◽

Genes Expression ◽

Profile Changes ◽

Senescence Associated Genes

Piper betle (PB) is a traditional medicine that is widely used to treat different diseases around Asian region. The leaf extracts contain various bioactive compounds, which were reported to have antidiabetic, antibacterial, anti-inflammatory, antioxidant, and anticancer effects. In this study, the effect of PB aqueous extracts on replicative senescent human diploid fibroblasts (HDFs) was investigated by determining the expressions of senescence-associated genes using quantitative PCR. Our results showed that PB extracts at 0.4 mg/ml can improve cell proliferation of young (143%), presenescent (127.3%), and senescent (157.3%) HDFs. Increased expressions of PRDX6, TP53, CDKN2A, PAK2, and MAPK14 were observed in senescent HDFs compared to young and/or presenescent HDFs. Treatment with PB extracts modulates the transcriptional profile changes in senescent HDFs. By contrast, expressions of SOD1 increased, whereas GPX1, PRDX6, TP53, CDKN2A, PAK2, and MAPK14 were decreased in PB-treated senescent HDFs compared to untreated senescent HDFs. In conclusion, this study indicates the modulation of PB extracts on senescence-associated genes expression of replicative senescent HDFs. Further studies warrant determining the mechanism of PB in modulating replicative senescence of HDFs through these signaling pathways.

Download Full-text