Does Chlorella vulgaris modulates the expression of COL and MMP genes in skin ageing?
Chlorella vulgaris and expression of COL and MMP genes
Abstract
Chlorella vulgaris, a unicellular microalgae, produces many intracellular phytochemicals namely carotenoids, tocopherols, ubiquinone and protein. Skin ageing which is induced by oxidative stress involves decreased extracellular matrix synthesis and increased expression of enzymes that degrade the collagenous matrix. The objective of this study was to determine the effect of C. vulgaris on the expression of genes encoded for collagen (COL) and matrix metalloproteinases (MMPs) which are involved in skin ageing. Human diploid fibroblasts (HDFs) were obtained from circumcision foreskin of 8-12 year-old boys. HDFs were cultured into 3 groups: untreated control cells, cells with stress-induced premature senescence (SIPS; cells were induced with H2O2 at passage 6 for 2 weeks) and SIPS treated with C. vulgaris (prolonged C. vulgaris treatment started at passage 4 and combined treatment with H2O2 at passage 6 for 2 weeks). Senescence-associated ß-galactosidase (SA ß-gal) was determined using senescent cells histochemical staining kit (Sigma, USA). Expression of COLI, COLIII, COLIV, MMPI, MMPII and MMPIII genes was quantitatively analysed with real-time RT-PCR method (iScript™ One Step real-time PCR with SYBR® Green; Biorad). HDFs treated with H2O2 (SIPS) exhibited senescent morphological features of flattening and enlarged with increased expression of SA ß-gal (p<0.05). Gene expression analysis showed COLI was downregulated in SIPS and SIPS treated with C. vulgaris (p<0.05)while COLIII decreased in SIPS and increased in SIPS treated with C. vulgaris (p<0.05). Expression of MMPI was increased in SIPS and SIPS treated with C. vulgaris (p<0.05) indicating its synergistic effect with H2O2 treatment. In conclusion, in skin ageing,COLI and COLIII genes were downregulated while MMPI was upregulated. C. vulgaris modulated the expression of COL and MMP genes by downregulating COLI and upregulating COLIII and MMPI but it did not exert anti-ageing effect.
Keywords :
Chlorella vulgaris,
collagen,
gene expression,
MMP,
skin ageing,
Abstrak
Chlorella vulgaris, sejenismikroalga unisel, menghasilkan banyak fitokimia intrasel seperti karotenoid, tokoferol, ubikuinon dan protein. Penuaan kulit diaruh oleh tekanan oksidatif melibatkan penurunan sintesis matriks ekstrasel dan peningkatan ekspresi enzim yang mendegradasikan matriks kolagen. Objektif kajian yang dijalankan ini adalah untuk menentukan kesan C. vulgaris terhadap ekspresi gen-gen yang mengkodkan kolagen (COL) dan matriks metaloproteinase (MMP) yang terlibat di dalam penuaan kulit. Sel fibroblas diploid manusia (HDF) diperolehi daripada kulit khatan kanak-kanak lelaki yang berusia 8-12 tahun. HDF telah dikulturkan kepada 3 kumpulan: sel kawalan tanpa rawatan, sel dengan penuaan pramatang aruhan tekanan oksidatif (SIPS; sel diaruh dengan H2O2 pada pasaj 6 selama 2 minggu) dan SIPS yang dirawat dengan C. vulgaris (rawatan C. vulgaris berpanjangan bermula pada pasaj 4 dan gabungan rawatan dengan H2O2 pada pasaj 6 selama 2 minggu). ß-Galaktosidase berkait-penuaan ditentukan menggunakan kit pewarnaan histokimia sel senesen (Sigma, USA). Ekspresi gen COLI, COLIII, COLIV, MMPI, MMPII dan MMPIII dianalisa secara kuantitatif menggunakan kaedah real-time RT-PCR (iScript™ One Step real-time PCR with SYBR® Green; Biorad). HDF yang dirawat dengan H2O2 (SIPS) menunjukkan morfologi sel senesen seperti sel menjadi rata dan membesar dengan peningkatan ekspresi ß-galaktosidase berkait-penuaan (p<0.05). Analisa ekspresi gen menunjukkan COLI menurun di dalam SIPS dan SIPS yang dirawat dengan C. vulgaris (p<0.05)manakalaCOLIII menurun di dalam SIPS dan meningkat di dalam SIPS yang dirawat dengan C. vulgaris (p<0.05). Ekspresi MMPI meningkat (p<0.05) di dalam SIPS dan SIPS yang dirawat dengan C. vulgaris menunjukkan kesan sinergistiknya bersama dengan rawatan H2O2. Sebagai kesimpulannya, pada penuaan kulit, ekspresi gen COLI dan COLIII menurun manakala MMPI meningkat. C. vulgaris telah memodulasikan ekspresi genCOL danMMP dengan menurunkan ekspresi COLI dan meningkatkan ekspresi COLIII dan MMPI tetapi ia tidak menunjukkan kesan anti penuaan.
Kata Kunci :
Chlorella vulgaris,
ekspresi gen,
kolagen,
MMP,
penuaan kulit,
Correspondance Address
Assoc. Prof. Dr. Suzana Makpol, Department of Biochemistry, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur. Tel: 603-9289 7296 / 7222. Fax: 603-2693 8037. Email: suzanamakpol@yahoo.com
