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

Jaafar F, Durani LW, Makpol S

Mol Biol Rep, 2020 Jan;47(1):369-379.
PMID: 31642042 DOI: 10.1007/s11033-019-05140-8

Human diploid fibroblasts (HDFs) cultured in vitro have limited capacity to proliferate after population doubling is repeated several times, and they enter into a state known as replicative senescence or cellular senescence. This study aimed to investigate the effect of Chlorella vulgaris on the replicative senescence of HDFs by determining the expression of senescence-associated genes. Young and senescent HDFs were divided into untreated control and C. vulgaris-treated groups. A senescence-associated gene transcription analysis was carried out with qRT-PCR. Treatment of young HDFs with C. vulgaris reduced the expression of SOD1, CAT and CCS (p
Fulltext Cellular Uptake and Bioavailability of Tocotrienol-Rich Fraction in SIRT1-Inhibited Human Diploid Fibroblasts

Jaafar F, Abdullah A, Makpol S

Sci Rep, 2018 Jul 11;8(1):10471.
PMID: 29992988 DOI: 10.1038/s41598-018-28708-z

Tocotrienol-rich fraction (TRF) is palm vitamin E that consists of tocopherol and tocotrienol. TRF is involved in important cellular regulation including delaying cellular senescence. A key regulator of cellular senescence, Sirtuin 1 (SIRT1) is involved in lipid metabolism. Thus, SIRT1 may regulate vitamin E transportation and bioavailability at cellular level. This study aimed to determine the role of SIRT1 on cellular uptake and bioavailability of TRF in human diploid fibroblasts (HDFs). SIRT1 gene in young HDFs was silenced by small interference RNA (siRNA) while SIRT1 activity was inhibited by sirtinol. TRF treatment was given for 24 h before or after SIRT1 inhibition. Cellular concentration of TRF isomers was determined according to the time points of before and after TRF treatment at 0, 24, 48, 72 and 96 h. Our results showed that all tocotrienol isomers were significantly taken up by HDFs after 24 h of TRF treatment and decreased 24 h after TRF treatment was terminated but remained in the cell up to 72 h. The uptake of α-tocopherol, α-tocotrienol and β-tocotrienol was significantly higher in senescent cells as compared to young HDFs indicating higher requirement for vitamin E in senescent cells. Inhibition of SIRT1 gene increased the uptake of all tocotrienol isomers but not α-tocopherol. However, SIRT1 inhibition at protein level decreased tocotrienol concentration. In conclusion, SIRT1 may regulate the cellular uptake and bioavailability of tocotrienol isomers in human diploid fibroblast cells while a similar regulation was not shown for α-tocopherol.
Fulltext Proteomic profiling of senescent human diploid fibroblasts treated with gamma-tocotrienol

Tan JK, Jaafar F, Makpol S

BMC Complement Altern Med, 2018 Nov 29;18(1):314.
PMID: 30497457 DOI: 10.1186/s12906-018-2383-6

BACKGROUND: Replicative senescence of human diploid fibroblasts (HDFs) has been used as a model to study mechanisms of cellular aging. Gamma-tocotrienol (γT3) is one of the members of vitamin E family which has been shown to increase proliferation of senescent HDFs. However, the modulation of protein expressions by γT3 in senescent HDFs remains to be elucidated. Therefore, this study aimed to determine the differentially expressed proteins (DEPs) in young and senescent HDFs; and in vehicle- and γT3-treated senescent HDFs using label-free quantitative proteomics.
METHODS: Whole proteins were extracted and digested in-gel with trypsin. Peptides were detected by Orbitrap liquid chromatography mass spectrometry. Mass spectra were identified and quantitated by MaxQuant software. The data were further filtered and analyzed statistically using Perseus software to identify DEPs. Functional annotations of DEPs were performed using Panther Classification System.
RESULTS: A total of 1217 proteins were identified in young and senescent cells, while 1218 proteins in vehicle- and γT3-treated senescent cells. 11 DEPs were found in young and senescent cells which included downregulation of platelet-derived growth factor (PDGF) receptor beta and upregulation of tubulin beta-2A chain protein expressions in senescent cells. 51 DEPs were identified in vehicle- and γT3-treated senescent cells which included upregulation of 70 kDa heat shock protein, triosephosphate isomerase and malate dehydrogenase protein expressions in γT3-treated senescent cells.
CONCLUSIONS: PDGF signaling and cytoskeletal structure may be dysregulated in senescent HDFs. The pro-proliferative effect of γT3 on senescent HDFs may be mediated through the stimulation of cellular response to stress and carbohydrate metabolism. The expressions and roles of these proteins in relation to cellular senescence are worth further investigations. Data are available via ProteomeXchange with identifier PXD009933.
γ-Tocotrienol prevents cell cycle arrest in aged human fibroblast cells through p16INK4a pathway

Zainuddin A, Chua KH, Tan JK, Jaafar F, Makpol S

J Physiol Biochem, 2017 Feb;73(1):59-65.
PMID: 27743340 DOI: 10.1007/s13105-016-0524-2

Human diploid fibroblasts (HDFs) proliferation in culture has been used as a model of aging at the cellular level. Growth arrest is one of the most important mechanisms responsible for replicative senescence. Recent researches have been focusing on the function of vitamin E in modulating cellular signaling and gene expression. Therefore, the aim of this study was to elucidate the effect of palm γ-tocotrienol (vitamin E) in modulating cellular aging through p16INK4a pathway in HDF cells. Primary culture of senescent HDFs was incubated with 70 μM of palm γ-tocotrienol for 24 hours. Silencing of p16INK4a was carried out by siRNA transfection. RNA was extracted from the different treatment groups and gene expression analysis was carried out by real-time reverse transcription polymerase chain reaction. Proteins that were regulated by p16INK4a were determined by western blot technique. The finding of this study showed that p16INK4a mRNA was overexpressed in senescent HDFs, and hypophosphorylated-pRb and cyclin D1 protein expressions were increased (p
Fulltext Zingiber Officinale Roscoe Prevents Cellular Senescence of Myoblasts in Culture and Promotes Muscle Regeneration

Mohd Sahardi NFN, Jaafar F, Mad Nordin MF, Makpol S

Evid Based Complement Alternat Med, 2020;2020:1787342.
PMID: 32419792 DOI: 10.1155/2020/1787342

Background: Ageing resulted in a progressive loss of muscle mass and strength. Increased oxidative stress in ageing affects the capacity of the myoblast to differentiate leading to impairment of muscle regeneration. Zingiber officinale Roscoe (ginger) has potential benefits in reversing muscle ageing due to its antioxidant property. This study aimed to determine the effect of ginger in the prevention of cellular senescence and promotion of muscle regeneration.
Methods: Myoblast cells were cultured into young and senescent state before treated with different concentrations of ginger standardised extracts containing different concentrations of 6-gingerol and 6-shogaol. Analysis on cellular morphology and myogenic purity was carried out besides determination of SA-β-galactosidase expression and cell cycle profile. Myoblast differentiation was quantitated by determining the fusion index, maturation index, and myotube size.
Results: Treatment with ginger extracts resulted in improvement of cellular morphology of senescent myoblasts which resembled the morphology of young myoblasts. Our results also showed that ginger treatment caused a significant reduction in SA-β-galactosidase expression on senescent myoblasts indicating prevention of cellular senescence, while cell cycle analysis showed a significant increase in the percentage of cells in the G0/G1 phase and reduction in the S-phase cells. Increased myoblast regenerative capacity was observed as shown by the increased number of nuclei per myotube, fusion index, and maturation index.
Conclusions: Ginger extracts exerted their potency in promoting muscle regeneration as indicated by prevention of cellular senescence and promotion of myoblast regenerative capacity.
Fulltext Gelam honey attenuated radiation-induced cell death in human diploid fibroblasts by promoting cell cycle progression and inhibiting apoptosis

Tengku Ahmad TA, Jaafar F, Jubri Z, Abdul Rahim K, Rajab NF, Makpol S

BMC Complement Altern Med, 2014;14:108.
PMID: 24655584 DOI: 10.1186/1472-6882-14-108

The interaction between ionizing radiation and substances in cells will induce the production of free radicals. These free radicals inflict damage to important biomolecules such as chromosomes, proteins and lipids which consequently trigger the expression of genes which are involved in protecting the cells or repair the oxidative damages. Honey has been known for its antioxidant properties and was used in medical and cosmetic products. Currently, research on honey is ongoing and diversifying. The aim of this study was to elucidate the role of Gelam honey as a radioprotector in human diploid fibroblast (HDFs) which were exposed to gamma-rays by determining the expression of genes and proteins involved in cell cycle regulation and cell death.
Fulltext Tsukamurella tyrosinosolvens intravascular catheter-related bacteremia in a haematology patient: a case report

Karunakaran R, Halim HA, Ng KP, Hanifah YA, Chin E, Jaafar FL, et al.

Eur Rev Med Pharmacol Sci, 2011 Nov;15(11):1343-6.
PMID: 22195371

Tsukamurella spp. are a rare but important cause of intravascular catheter-related bacteremia in immunocompromised patients. The organism is an aerobic, Gram-positive, weakly acid-fast bacillus that is difficult to differentiate using standard laboratory methods from other aerobic actinomycetales such as Nocardia spp., Rhododoccus spp., Gordonia spp., and the rapid growing Mycobacterium spp. We report a case of Tsukamurella tyrosinosolvens catheter-related bacteremia in a 51-year-old haematology patient who responded to treatment with imipenem and subsequent line removal. 16srRNA sequencing allowed for the prompt identification of this organism.
Malaysianol A, a new trimer resveratrol oligomer from the stem bark of Dryobalanops aromatica

Wibowo A, Ahmat N, Hamzah AS, Sufian AS, Ismail NH, Ahmad R, et al.

Fitoterapia, 2011 Jun;82(4):676-81.
PMID: 21338657 DOI: 10.1016/j.fitote.2011.02.006

A new resveratrol trimer, malaysianol A (1), five known resveratrol oligomers: laevifonol (2), ampelopsin E (3), α-viniferin (4), ε-viniferin (5), diptoindonesin A (6), and bergenin (7) have been isolated from the acetone extract of the stem bark of Dryobalanops aromatica by combination of vacuum and radial chromatography techniques. Their structures were established on the basis of their spectroscopic evidence and comparison with the published data. The cytotoxic activity of the compounds was tested against several cell lines in which compound 4 was found to inhibit strongly the growth of HL-60 cell line.
Targeting genes in insulin-associated signalling pathway, DNA damage, cell proliferation and cell differentiation pathways by tocotrienol-rich fraction in preventing cellular senescence of human diploid fibroblasts

Durani LW, Jaafar F, Tan JK, Tajul Arifin K, Mohd Yusof YA, Wan Ngah WZ, et al.

Clin Ter, 2016;166(6):e365-73.
PMID: 26794818 DOI: 10.7417/T.2015.1902

Tocotrienols have been known for their antioxidant properties besides their roles in cellular signalling, gene expression, immune response and apoptosis. This study aimed to determine the molecular mechanism of tocotrienol-rich fraction (TRF) in preventing cellular senescence of human diploid fibroblasts (HDFs) by targeting the genes in senescence-associated signalling pathways.
Fulltext Sex Determination and Differentiation in Teleost: Roles of Genetics, Environment, and Brain

Rajendiran P, Jaafar F, Kar S, Sudhakumari C, Senthilkumaran B, Parhar IS

Biology (Basel), 2021 Sep 27;10(10).
PMID: 34681072 DOI: 10.3390/biology10100973

The fish reproductive system is a complex biological system. Nonetheless, reproductive organ development is conserved, which starts with sex determination and then sex differentiation. The sex of a teleost is determined and differentiated from bipotential primordium by genetics, environmental factors, or both. These two processes are species-specific. There are several prominent genes and environmental factors involved during sex determination and differentiation. At the cellular level, most of the sex-determining genes suppress the female pathway. For environmental factors, there are temperature, density, hypoxia, pH, and social interaction. Once the sexual fate is determined, sex differentiation takes over the gonadal developmental process. Environmental factors involve activation and suppression of various male and female pathways depending on the sexual fate. Alongside these factors, the role of the brain during sex determination and differentiation remains elusive. Nonetheless, GnRH III knockout has promoted a male sex-biased population, which shows brain involvement during sex determination. During sex differentiation, LH and FSH might not affect the gonadal differentiation, but are required for regulating sex differentiation. This review discusses the role of prominent genes, environmental factors, and the brain in sex determination and differentiation across a few teleost species.
Fulltext Elucidating the Pharmacological Properties of Zingiber officinale Roscoe (Ginger) on Muscle Ageing by Untargeted Metabolomic Profiling of Human Myoblasts

Mohd Sahardi NFN, Jaafar F, Tan JK, Mad Nordin MF, Makpol S

Nutrients, 2023 Oct 25;15(21).
PMID: 37960173 DOI: 10.3390/nu15214520

(1) Background: Muscle loss is associated with frailty and a reduction in physical strength and performance, which is caused by increased oxidative stress. Ginger (Zingiber officinale Roscoe) is a potential herb that can be used to reduce the level of oxidative stress. This study aimed to determine the effect of ginger on the expression of metabolites and their metabolic pathways in the myoblast cells to elucidate the mechanism involved and its pharmacological properties in promoting myoblast differentiation. (2) Methods: The myoblast cells were cultured into three stages (young, pre-senescent and senescent). At each stage, the myoblasts were treated with different concentrations of ginger extract. Then, metabolomic analysis was performed using liquid chromatography-tandem mass spectrometry (LCMS/MS). (3) Results: Nine metabolites were decreased in both the pre-senescent and senescent control groups as compared to the young control group. For the young ginger-treated group, 8-shogaol and valine were upregulated, whereas adipic acid and bis (4-ethyl benzylidene) sorbitol were decreased. In the pre-senescent ginger-treated group, the niacinamide was upregulated, while carnitine and creatine were downregulated. Ginger treatment in the senescent group caused a significant upregulation in 8-shogaol, octadecanamide and uracil. (4) Conclusions: Ginger extract has the potential as a pharmacological agent to reduce muscle loss in skeletal muscle by triggering changes in some metabolites and their pathways that could promote muscle regeneration in ageing.
Fulltext Targeting myomiRs by tocotrienol-rich fraction to promote myoblast differentiation

Razak AM, Khor SC, Jaafar F, Karim NA, Makpol S

Genes Nutr, 2018;13:31.
PMID: 30519366 DOI: 10.1186/s12263-018-0618-2

Background: Several muscle-specific microRNAs (myomiRs) are differentially expressed during cellular senescence. However, the role of dietary compounds on myomiRs remains elusive. This study aimed to elucidate the modulatory role of tocotrienol-rich fraction (TRF) on myomiRs and myogenic genes during differentiation of human myoblasts. Young and senescent human skeletal muscle myoblasts (HSMM) were treated with 50 μg/mL TRF for 24 h before and after inducing differentiation.
Results: The fusion index and myotube surface area were higher (p
Fulltext A Current Update on the Distribution, Morphological Features, and Genetic Identity of the Southeast Asian Mahseers, Tor Species

Jaafar F, Na-Nakorn U, Srisapoome P, Amornsakun T, Duong TY, Gonzales-Plasus MM, et al.

Biology (Basel), 2021 Apr 01;10(4).
PMID: 33915909 DOI: 10.3390/biology10040286

The king of rivers or mahseer comprises three genera: Tor, Neolissochilus, and Naziritor, under the Cyprinidae family. The Tor genus has been classified as the true mahseer due to the presence of a median lobe among the three genera. The Tor species are widely distributed across Southeast (SE) Asia, and 13 Tor species have been reported previously: Tor ater, Tor dongnaiensis, Tor douronensis, Tor laterivittatus, Tor mosal, Tor mekongensis, Tor putitora, Tor sinensis, Tor soro, Tor tambra, Tor tambroides, Tor tor and Tor yingjiangensis. However, the exact number of valid Tor species remains debatable. Different and unstandardized approaches of applying genetic markers in taxonomic identification and morphology variation within the same species have further widened the gap and ameliorated the instability of Tor species taxonomy. Therefore, synchronized and strategized research among Tor species researchers is urgently required to improve and fill the knowledge gap. This review is a current update of SE Asia's Tor species, outlining their distribution, morphology, and genetic identification. In addition, the present review proposes that there are ten valid Tor species in the SE Asian region. This list will serve as a template and standard to improve the taxonomy of the SE Asian Tor species, which could serve as a basis to open new directions in Tor research.
Fulltext Comparative Effects of Alpha- and Gamma-Tocopherol on Mitochondrial Functions in Alzheimer's Disease In Vitro Model

Pahrudin Arrozi A, Shukri SNS, Wan Ngah WZ, Mohd Yusof YA, Ahmad Damanhuri MH, Jaafar F, et al.

Sci Rep, 2020 06 02;10(1):8962.
PMID: 32488024 DOI: 10.1038/s41598-020-65570-4

Vitamin E acts as an antioxidant and reduces the level of reactive oxygen species (ROS) in Alzheimer's disease (AD). Alpha-tocopherol (ATF) is the most widely studied form of vitamin E besides gamma-tocopherol (GTF) which also shows beneficial effects in AD. The levels of amyloid-beta (Aβ) and amyloid precursor protein (APP) increased in the brains of AD patients, and mutations in the APP gene are known to enhance the production of Aβ. Mitochondrial function was shown to be affected by the increased level of Aβ and may induce cell death. Here, we aimed to compare the effects of ATF and GTF on their ability to reduce Aβ level, modulate mitochondrial function and reduce the apoptosis marker in SH-SY5Y cells stably transfected with the wild-type or mutant form of the APP gene. The Aβ level was measured by ELISA, the mitochondrial ROS and ATP level were quantified by fluorescence and luciferase assay respectively whereas the complex V enzyme activity was measured by spectrophotometry. The expressions of genes involved in the regulation of mitochondrial membrane permeability such as voltage dependent anion channel (VDAC1), adenine nucleotide translocase (ANT), and cyclophilin D (CYPD) were determined by quantitative real-time polymerase chain reaction (qRT-PCR), while the expressions of cyclophilin D (CypD), cytochrome c, Bcl2 associated X (BAX), B cell lymphoma-2 (Bcl-2), and pro-caspase-3 were determined by western blot. Our results showed that mitochondrial ROS level was elevated accompanied by decreased ATP level and complex V enzyme activity in SH-SY5Y cells expressing the mutant APP gene (p
Fulltext Modulation of Ki67 and myogenic regulatory factor expression by tocotrienol-rich fraction ameliorates myogenic program of senescent human myoblasts

Tan CM, Najib NAM, Suhaimi NF, Halid NA, Cho VV, Abdullah SI, et al.

Arch Med Sci, 2021;17(3):752-763.
PMID: 34025846 DOI: 10.5114/aoms.2019.85449

Introduction: Replicative senescence results in dysregulation of cell proliferation and differentiation, which plays a role in the regenerative defects observed during age-related muscle atrophy. Vitamin E is a well-known antioxidant, which potentially ameliorates a wide range of age-related manifestations. The aim of this study was to determine the effects of tocotrienol-rich fraction (TRF) in modulating the expression of proliferation- and differentiation-associated proteins in senescent human myoblasts during the differentiation phase.
Material and methods: Human skeletal muscle myoblasts were cultured until senescence. Young and senescent cells were treated with TRF for 24 h before and after differentiation induction, followed by evaluation of cellular morphology and efficiency of differentiation. Expression of cell proliferation marker Ki67 protein and myogenic regulatory factors MyoD and myogenin were determined.
Results: Our findings showed that treatment with TRF significantly improved the morphology of senescent myoblasts. Promotion of differentiation was observed in young and senescent myoblasts with TRF treatment as shown by the increased fusion index and larger size of myotubes. Increased Ki67 and myogenin expression with TRF treatment was also observed in senescent myoblasts, suggesting amelioration of the myogenic program by TRF during replicative senescence.
Conclusions: TRF modulates the expression of regulatory factors related to proliferation and differentiation in senescent human myoblasts and could be beneficial for ameliorating the regenerative defects during aging.
Recombinant VP9-based enzyme-linked immunosorbent assay for detection of immunoglobulin G antibodies to Banna virus (genus Seadornavirus)

Mohd Jaafar F, Attoui H, Gallian P, Isahak I, Wong KT, Cheong SK, et al.

J Virol Methods, 2004 Mar 01;116(1):55-61.
PMID: 14715307

Banna virus (BAV, genus Seadornavirus, family Reoviridae) is an arbovirus suspected to be responsible for encephalitis in humans. Two genotypes of this virus are distinguishable: A (Chinese isolate, BAV-Ch) and B (Indonesian isolate, BAV-In6969) which exhibit only 41% amino-acid identity in the sequence of their VP9. The VP7 to VP12 of BAV-Ch and VP9 of BAV-In6969 were expressed in bacteria using pGEX-4T-2 vector. VP9 was chosen to establish an ELISA for BAV, based mainly on two observations: (i). VP9 is a major protein in virus-infected cells and is a capsid protein (ii). among all the proteins expressed, VP9 was obtained in high amount and showed the highest immuno-reactivity to anti-BAV ascitic fluid. The VP9s ELISA was evaluated in three populations: French blood donors and two populations (blood donors and patients with a neurological syndrome) from Malaysia, representing the region where the virus was isolated in the past. The specificity of this ELISA was >98%. In mice injected with live BAV, the assay detected IgG-antibody to BAV infection 21 days post-injection, which was confirmed by Western blot using BAV-infected cells. The VP9 ELISA permits to determine the sero-status of a population without special safety precautions and without any requirements to propagate the BAV. This test should be a useful tool for epidemiological survey of BAV.
Fulltext Metabolomics Profiling of Age-Associated Metabolites in Malay Population

Tan JK, Zakaria SNA, Gunasekaran G, Abdul Sani NF, Nasaruddin ML, Jaafar F, et al.

Oxid Med Cell Longev, 2023;2023:4416410.
PMID: 36785791 DOI: 10.1155/2023/4416410

Aging is a complex process characterized by progressive loss of functional abilities due to the accumulation of molecular damages. Metabolomics could offer novel insights into the predictors and mechanisms of aging. This cross-sectional study is aimed at identifying age-associated plasma metabolome in a Malay population. A total of 146 (90 females) healthy participants aged 28-69 were selected for the study. Untargeted metabolomics profiling was performed using liquid chromatography-tandem mass spectrometry. Association analysis was based on the general linear model. Gender-associated metabolites were adjusted for age, while age-associated metabolites were adjusted for gender or analyzed in a gender-stratified manner. Gender-associated metabolites such as 4-hydroxyphenyllactic acid, carnitine, cortisol, and testosterone sulfate showed higher levels in males than females. Deoxycholic acid and hippuric acid were among the metabolites with a positive association with age after being adjusted for gender, while 9(E),11(E)-conjugated linoleic acid, cortisol, and nicotinamide were negatively associated with age. In gender-stratified analysis, glutamine was one of the common metabolites that showed a direct association with age in both genders, while metabolites such as 11-deoxy prostaglandin F2β, guanosine monophosphate, and testosterone sulfate were inversely associated with age in males and females. This study reveals several age-associated metabolites in Malays that could reflect the changes in metabolisms during aging and may be used to discern the risk of geriatric syndromes and disorders later. Further studies are required to determine the interplay between these metabolites and environmental factors on the functional outcomes during aging.

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