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Gelam honey and ginger potentiate the anti cancer effect of 5-FU against HCT 116 colorectal cancer cells

Hakim L, Alias E, Makpol S, Ngah WZ, Morad NA, Yusof YA

Asian Pac J Cancer Prev, 2014;15(11):4651-7.
PMID: 24969899

The development of chemopreventive approaches using a concoction of phytochemicals is potentially viable for combating many types of cancer including colon carcinogenesis. This study evaluated the anti-proliferative effects of ginger and Gelam honey and its efficacy in enhancing the anti-cancer effects of 5-FU (5-fluorouracil) against a colorectal cancer cell line, HCT 116. Cell viability was measured via MTS (3-(4,5-dimethylthiazol-2- yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphenyl)-2H-tetrazolium) assay showing ginger inhibiting the growth of HCT 116 cells more potently (IC50 of 3mg/mL) in comparison to Gelam honey (IC50 of 75 mg/mL). Combined treatment of the two compounds (3mg/mL ginger+75 mg/mL Gelam honey) synergistically lowered the IC50 of Gelam honey to 22 mg/mL. Combination with 35 mg/mL Gelam honey markedly enhanced 5-FU inhibiting effects on the growth of HCT 116 cells. Subsequent analysis on the induction of cellular apoptosis suggested that individual treatment of ginger and Gelam honey produced higher apoptosis than 5-FU alone. In addition, treatment with the combination of two natural compounds increased the apoptotic rate of HCT 116 cells dose- dependently while treatment of either ginger or Gelam honey combined with 5-FU only showed modest changes. Combination index analysis showed the combination effect of both natural compounds to be synergistic in their inhibitory action against HCT 116 colon cancer cells (CI 0.96 < 1). In conclusion, combined treatment of Gelam honey and ginger extract could potentially enhance the chemotherapeutic effect of 5-FU against colorectal cancer.
Fulltext Effect of the combination of gelam honey and ginger on oxidative stress and metabolic profile in streptozotocin-induced diabetic Sprague-Dawley rats

Sani NF, Belani LK, Sin CP, Rahman SN, Das S, Chi TZ, et al.

Biomed Res Int, 2014;2014:160695.
PMID: 24822178 DOI: 10.1155/2014/160695

Diabetic complications occur as a result of increased reactive oxygen species (ROS) due to long term hyperglycaemia. Honey and ginger have been shown to exhibit antioxidant activity which can scavenge ROS. The main aim of this study was to evaluate the antioxidant and antidiabetic effects of gelam honey, ginger, and their combination. Sprague-Dawley rats were divided into 2 major groups which consisted of diabetic and nondiabetic rats. Diabetes was induced with streptozotocin intramuscularly (55 mg/kg body weight). Each group was further divided into 4 smaller groups according to the supplements administered: distilled water, honey (2 g/kg body weight), ginger (60 mg/kg body weight), and honey + ginger. Body weight and glucose levels were recorded weekly, while blood from the orbital sinus was obtained after 3 weeks of supplementation for the estimation of metabolic profile: glucose, triglyceride (TG), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH): oxidized glutathione (GSSG), and malondialdehyde (MDA). The combination of gelam honey and ginger did not show hypoglycaemic potential; however, the combination treatment reduced significantly (P < 0.05) SOD and CAT activities as well as MDA level, while GSH level and GSH/GSSG ratio were significantly elevated (P < 0.05) in STZ-induced diabetic rats compared to diabetic control rats.
Fulltext γ-Tocotrienol and 6-Gingerol in Combination Synergistically Induce Cytotoxicity and Apoptosis in HT-29 and SW837 Human Colorectal Cancer Cells

Yusof KM, Makpol S, Jamal R, Harun R, Mokhtar N, Ngah WZ

Molecules, 2015 Jun 03;20(6):10280-97.
PMID: 26046324 DOI: 10.3390/molecules200610280

Numerous bioactive compounds have cytotoxic properties towards cancer cells. However, most studies have used single compounds when bioactives may target different pathways and exert greater cytotoxic effects when used in combination. Therefore, the objective of this study was to determine the anti-proliferative effect of γ-tocotrienol (γ-T3) and 6-gingerol (6G) in combination by evaluating apoptosis and active caspase-3 in HT-29 and SW837 colorectal cancer cells. MTS assays were performed to determine the anti-proliferative and cytotoxicity effect of γ-T3 (0-150 µg/mL) and 6G (0-300 µg/mL) on the cells. The half maximal inhibitory concentration (IC50) value of 6G+ γ-T3 for HT-29 was 105 + 67 µg/mL and for SW837 it was 70 + 20 µg/mL. Apoptosis, active caspase-3 and annexin V FITC assays were performed after 24 h of treatment using flow cytometry. These bioactives in combination showed synergistic effect on HT-29 (CI: 0.89 ± 0.02,) and SW837 (CI: 0.79 ± 0.10) apoptosis was increased by 21.2% in HT-29 and 55.4% in SW837 (p < 0.05) after 24 h treatment, while normal hepatic WRL-68 cells were unaffected. Increased apoptosis by the combined treatments was also observed morphologically, with effects like cell shrinkage and pyknosis. In conclusion, although further studies need to be done, γ-T3 and 6G when used in combination act synergistically increasing cytotoxicity and apoptosis in cancer cells.
Tocotrienol-rich fraction prevents cellular aging by modulating cell proliferation signaling pathways

Khor SC, Mohd Yusof YA, Wan Ngah WZ, Makpol S

Clin Ter, 2015;166(2):e81-90.
PMID: 25945449 DOI: 10.7417/CT.2015.1825

BACKGROUND AND OBJECTIVE: Vitamin E has been suggested as nutritional intervention for the prevention of degenerative and age-related diseases. In this study, we aimed to elucidate the underlying mechanism of tocotrienol-rich fraction (TRF) in delaying cellular aging by targeting the proliferation signaling pathways in human diploid fibroblasts (HDFs).
MATERIALS AND METHODS: Tocotrienol-rich fraction was used to treat different stages of cellular aging of primary human diploid fibroblasts viz. young (passage 6), pre-senescent (passage 15) and senescent (passage 30). Several selected targets involved in the downstream of PI3K/AKT and RAF/MEK/ERK pathways were compared in total RNA and protein.
RESULTS: Different transcriptional profiles were observed in young, pre-senescent and senescent HDFs, in which cellular aging increased AKT, FOXO3, CDKN1A and RSK1 mRNA expression level, but decreased ELK1, FOS and SIRT1 mRNA expression level. With tocotrienol-rich fraction treatment, gene expression of AKT, FOXO3, ERK and RSK1 mRNA was decreased in senescent cells, but not in young cells. The three down-regulated mRNA in cellular aging, ELK1, FOS and SIRT1, were increased with tocotrienol-rich fraction treatment. Expression of FOXO3 and P21Cip1 proteins showed up-regulation in senescent cells but tocotrienol-rich fraction only decreased P21Cip1 protein expression in senescent cells.
CONCLUSIONS: Tocotrienol-rich fraction exerts gene modulating properties that might be responsible in promoting cell cycle progression during cellular aging.
Fulltext Combined ginger extract & Gelam honey modulate Ras/ERK and PI3K/AKT pathway genes in colon cancer HT29 cells

Tahir AA, Sani NF, Murad NA, Makpol S, Ngah WZ, Yusof YA

Nutr J, 2015;14:31.
PMID: 25889965 DOI: 10.1186/s12937-015-0015-2

The interconnected Ras/ERK and PI3K/AKT pathways play a central role in colorectal tumorigenesis, and they are targets for elucidating mechanisms involved in attempts to induce colon cancer cell death. Both ginger (Zingiber officinale) and honey have been shown to exhibit anti-tumor and anti-inflammation properties against many types of cancer, including colorectal cancer. However, there are currently no reports showing the combined effect of these two dietary compounds in cancer growth inhibition. The aim of this study was to evaluate the synergistic effect of crude ginger extract and Gelam honey in combination as potential cancer chemopreventive agents against the colorectal cancer cell line HT29.
Mechanism of Chemoprevention against Colon Cancer Cells Using Combined Gelam Honey and Ginger Extract via mTOR and Wnt/β-catenin Pathways

Wee LH, Morad NA, Aan GJ, Makpol S, Wan Ngah WZ, Mohd Yusof YA

Asian Pac J Cancer Prev, 2015;16(15):6549-56.
PMID: 26434873

The PI3K-Akt-mTOR, Wnt/β-catenin and apoptosis signaling pathways have been shown to be involved in genesis of colorectal cancer (CRC). The aim of this study was to elucidate whether combination of Gelam honey and ginger might have chemopreventive properties in HT29 colon cancer cells by modulating the mTOR, Wnt/β-catenin and apoptosis signaling pathways. Treatment with Gelam honey and ginger reduced the viability of the HT29 cells dose dependently with IC50 values of 88 mg/ml and 2.15 mg/ml respectively, their while the combined treatment of 2 mg/ml of ginger with 31 mg/ml of Gelam honey inhibited growth of most HT29 cells. Gelam honey, ginger and combination induced apoptosis in a dose dependent manner with the combined treatment exhibiting the highest apoptosis rate. The combined treatment downregulated the gene expressions of Akt, mTOR, Raptor, Rictor, β-catenin, Gsk3β, Tcf4 and cyclin D1 while cytochrome C and caspase 3 genes were shown to be upregulated. In conclusion, the combination of Gelam honey and ginger may serve as a potential therapy in the treatment of colorectal cancer through inhibiton of mTOR, Wnt/β catenin signaling pathways and induction of apoptosis pathway.
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 The Tocotrienol-Rich Fraction Is Superior to Tocopherol in Promoting Myogenic Differentiation in the Prevention of Replicative Senescence of Myoblasts

Khor SC, Razak AM, Wan Ngah WZ, Mohd Yusof YA, Abdul Karim N, Makpol S

PLoS One, 2016;11(2):e0149265.
PMID: 26885980 DOI: 10.1371/journal.pone.0149265

Aging results in a loss of muscle mass and strength. Myoblasts play an important role in maintaining muscle mass through regenerative processes, which are impaired during aging. Vitamin E potentially ameliorates age-related phenotypes. Hence, this study aimed to determine the effects of the tocotrienol-rich fraction (TRF) and α-tocopherol (ATF) in protecting myoblasts from replicative senescence and promoting myogenic differentiation. Primary human myoblasts were cultured into young and senescent stages and were then treated with TRF or ATF for 24 h, followed by an analysis of cell proliferation, senescence biomarkers, cellular morphology and differentiation. Our data showed that replicative senescence impaired the normal regenerative processes of myoblasts, resulting in changes in cellular morphology, cell proliferation, senescence-associated β-galactosidase (SA-β-gal) expression, myogenic differentiation and myogenic regulatory factors (MRFs) expression. Treatment with both TRF and ATF was beneficial to senescent myoblasts in reclaiming the morphology of young cells, improved cell viability and decreased SA-β-gal expression. However, only TRF treatment increased BrdU incorporation in senescent myoblasts, as well as promoted myogenic differentiation through the modulation of MRFs at the mRNA and protein levels. MYOD1 and MYOG gene expression and myogenin protein expression were modulated in the early phases of myogenic differentiation. In conclusion, the tocotrienol-rich fraction is superior to α-tocopherol in ameliorating replicative senescence-related aberration and promoting differentiation via modulation of MRFs expression, indicating vitamin E potential in modulating replicative senescence of myoblasts.
Piper betle Induced Cytoprotective Genes and Proteins via the Nrf2/ARE Pathway in Aging Mice

Aliahmat NS, Abdul Sani NF, Wan Hasan WN, Makpol S, Wan Ngah WZ, Mohd Yusof YA

J Nutrigenet Nutrigenomics, 2016;9(5-6):243-253.
PMID: 28002828 DOI: 10.1159/000452407

BACKGROUND/AIMS: The objective of this study was to elucidate the underlying antioxidant mechanism of aqueous extract of Piper betle (PB) in aging rats. The nuclear factor erythroid 2-related factor 2 (Nrf2)/ARE pathway involving phase II detoxifying and antioxidant enzymes plays an important role in the antioxidant system by reducing electrophiles and reactive oxygen species through induction of phase II enzymes and proteins.
METHODS: Genes and proteins of phase II detoxifying antioxidant enzymes were analyzed by QuantiGenePlex 2.0 Assay and Western blot analysis.
RESULTS: PB significantly induced genes and proteins of phase II and antioxidant enzymes, NAD(P)H quinone oxidoreductase 1, and catalase in aging mice (p < 0.05). The expression of these enzymes were stimulated via translocation of Nrf2 into the nucleus, indicating the involvement of ARE, a cis-acting motif located in the promoter region of nearly all phase II genes.
CONCLUSIONS: PB was testified for the first time to induce cytoprotective genes through the Nrf2/ARE signaling pathway, thus unraveling the antioxidant mechanism of PB during the aging process.
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
Antioxidant modulation in restoring mitochondrial function in neurodegeneration

Pahrudin Arrozi A, Wan Ngah WZ, Mohd Yusof YA, Ahmad Damanhuri MH, Makpol S

Int J Neurosci, 2017 Mar;127(3):218-235.
PMID: 27074540 DOI: 10.1080/00207454.2016.1178261

Alzheimer's disease (AD) and Parkinson's disease (PD) are the leading causes of disability associated with neurodegeneration worldwide. These diseases are influenced by multiple genetic and environmental factors and share similar mechanisms as both are characterized by accumulation and aggregation of misfolded proteins - amyloid-beta (Aβ) in AD and α-synuclein in PD. Over the past decade, increasing evidence has shown that mitochondrial dysfunction and the generation of reactive oxygen species (ROS) are involved in the pathology of these diseases, and the contributions of these defects to the cellular and molecular changes that eventually cause neuronal death have been explored. Using mitochondrial protective agents, such as antioxidants, to combat ROS provides a new strategy for neurodegenerative treatment. In this review, we highlight the potential of multiple types of antioxidants, including vitamins, phytochemicals, fatty acids and minerals, as well as synthetic antioxidants specifically targeting the mitochondria, which can restore mitochondrial function, in the treatment of neurodegenerative disorders at both the pre-clinical and clinical stages by focusing on AD and PD.
Evaluation of the Expression of Amyloid Precursor Protein and the Ratio of Secreted Amyloid Beta 42 to Amyloid Beta 40 in SH-SY5Y Cells Stably Transfected with Wild-Type, Single-Mutant and Double-Mutant Forms of the APP Gene for the Study of Alzheimer's Disease Pathology

Pahrudin Arrozi A, Shukri SNS, Wan Ngah WZ, Mohd Yusof YA, Ahmad Damanhuri MH, Makpol S

Appl Biochem Biotechnol, 2017 Nov;183(3):853-866.
PMID: 28417423 DOI: 10.1007/s12010-017-2468-6

Neuroblastoma cell lines such as SH-SY5Y are the most frequently utilized models in neurodegenerative research, and their use has advanced the understanding of the pathology of neurodegeneration over the past few decades. In Alzheimer's disease (AD), several pathogenic mutations have been described, all of which cause elevated levels of pathological hallmarks such as amyloid-beta (Aβ). Although the genetics of Alzheimer's disease is well known, familial AD only accounts for a small number of cases in the population, with the rest being sporadic AD, which contains no known mutations. Currently, most of the in vitro models used to study AD pathogenesis only examine the level of Aβ42 as a confirmation of successful model generation and only perform comparisons between wild-type APP and single mutants of the APP gene. Recent findings have shown that the Aβ42/40 ratio in cerebrospinal fluid (CSF) is a better diagnostic indicator for AD patients than is Aβ42 alone and that more extensive Aβ formation, such as accumulation of intraneuronal Aβ, Aβ plaques, soluble oligomeric Aβ (oAβ), and insoluble fibrillar Aβ (fAβ) occurs in TgCRND8 mice expressing a double-mutant form (Swedish and Indiana) of APP, later leading to greater progressive impairment of the brain. In this study, we generated SH-SY5Y cells stably transfected separately with wild-type APP, the Swedish mutation of APP, and the Swedish and Indiana mutations of APP and evaluated the APP expression as well as the Aβ42/40 ratio in those cells. The double-mutant form of APP (Swedish/Indiana) expressed markedly high levels of APP protein and showed a high Aβ2/40 ratio compared to wild-type and single-mutant cells.
Fulltext Age-related changes in the metabolic profiles of rat hippocampus, medial prefrontal cortex and striatum

Durani LW, Hamezah HS, Ibrahim NF, Yanagisawa D, Makpol S, Damanhuri HA, et al.

Biochem Biophys Res Commun, 2017 11 25;493(3):1356-1363.
PMID: 28970069 DOI: 10.1016/j.bbrc.2017.09.164

We have recently shown that age-dependent regional brain atrophy and lateral ventricle expansion may be linked with impaired cognitive and locomotor functions. However, metabolic profile transformation in different brain regions during aging is unknown. This study examined metabolic changes in the hippocampus, medial prefrontal cortex (mPFC) and striatum of middle- and late-aged Sprague-Dawley rats using ultrahigh performance liquid chromatography coupled with high-resolution accurate mass-orbitrap tandem mass spectrometry. Thirty-eight potential metabolites were altered in hippocampus, 29 in mPFC, and 14 in striatum. These alterations indicated that regional metabolic mechanisms in lated-aged rats are related to multiple pathways including glutathione, sphingolipid, tyrosine, and purine metabolism. Thus, our findings might be useful for understanding the complexity of metabolic mechanisms in aging and provide insight for aging and health span.
Fulltext Tocotrienol-Rich Fraction Ameliorates Antioxidant Defense Mechanisms and Improves Replicative Senescence-Associated Oxidative Stress in Human Myoblasts

Khor SC, Wan Ngah WZ, Mohd Yusof YA, Abdul Karim N, Makpol S

Oxid Med Cell Longev, 2017;2017:3868305.
PMID: 28243354 DOI: 10.1155/2017/3868305

During aging, oxidative stress affects the normal function of satellite cells, with consequent regeneration defects that lead to sarcopenia. This study aimed to evaluate tocotrienol-rich fraction (TRF) modulation in reestablishing the oxidative status of myoblasts during replicative senescence and to compare the effects of TRF with other antioxidants (α-tocopherol (ATF) and N-acetyl-cysteine (NAC)). Primary human myoblasts were cultured to young, presenescent, and senescent phases. The cells were treated with antioxidants for 24 h, followed by the assessment of free radical generation, lipid peroxidation, antioxidant enzyme mRNA expression and activities, and the ratio of reduced to oxidized glutathione. Our data showed that replicative senescence increased reactive oxygen species (ROS) generation and lipid peroxidation in myoblasts. Treatment with TRF significantly diminished ROS production and decreased lipid peroxidation in senescent myoblasts. Moreover, the gene expression of superoxide dismutase (SOD2), catalase (CAT), and glutathione peroxidase (GPX1) was modulated by TRF treatment, with increased activity of superoxide dismutase and catalase and reduced glutathione peroxidase in senescent myoblasts. In comparison to ATF and NAC, TRF was more efficient in heightening the antioxidant capacity and reducing free radical insults. These results suggested that TRF is able to ameliorate antioxidant defense mechanisms and improves replicative senescence-associated oxidative stress in myoblasts.
Fulltext Piper betle L. Modulates Senescence-Associated Genes Expression in Replicative Senescent Human Diploid Fibroblasts

Durani LW, Khor SC, Tan JK, Chua KH, Mohd Yusof YA, Makpol S

Biomed Res Int, 2017;2017:6894026.
PMID: 28596968 DOI: 10.1155/2017/6894026

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 ofPRDX6,TP53,CDKN2A,PAK2, andMAPK14were 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 ofSOD1increased, whereasGPX1,PRDX6,TP53,CDKN2A,PAK2, andMAPK14were 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.
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 Human adipose-derived mesenchymal stem cells promote recovery of injured HepG2 cell line and show sign of early hepatogenic differentiation

Liau LL, Makpol S, Azurah AGN, Chua KH

Cytotechnology, 2018 Aug;70(4):1221-1233.
PMID: 29549558 DOI: 10.1007/s10616-018-0214-8

Currently, orthotopic liver transplantation is the gold standard therapy for liver failure. However, it is limited by the insufficient organ donor and risk of immune rejection. Stem cell therapy is a promising alternative treatment for liver failure. One of the most ideal sources of stem cells for regenerative medicine is adipose-derived stem cells (ADSCs). In this study, primary ADSCs seeded on cell culture insert were indirectly co-cultured with injured HepG2 to elucidate the role of ADSCs in promoting the recovery of injured HepG2 in non-contact manner. HepG2 recovery was determined by the surface area covered by cells and growth factor concentration was measured to identify the factors involved in regeneration. Besides, HepG2 were collected for q-PCR analysis of injury, hepatocyte functional and regenerative markers expression. For the ADSCs, expression of hepatogenic differentiation genes was analyzed. Results showed that non-contact co-culture with ADSCs helped the recovery of injured HepG2. ELISA quantification revealed that ADSCs secreted higher amount of HGF and VEGF to help the recovery of injured HepG2. Furthermore, HepG2 co-cultured with ADSCs expressed significantly lower injury markers as well as significantly higher regenerative and functional markers compared to the control HepG2. ADSCs co-cultured with injured HepG2 expressed significantly higher hepatic related genes compared to the control ADSCs. In conclusion, ADSCs promote recovery of injured HepG2 via secretion of HGF and VEGF. In addition, co-cultured ADSCs showed early sign of hepatogenic differentiation in response to the factors released or secreted by the injured HepG2.
DNA damage and protein oxidation associated with ageing correlate with cognitive dysfunction in a Malaysian population

Abdul Sani NF, Ahmad Damanhuri MH, Amir Hamzah AIZ, Abu Bakar ZH, Tan JK, Nor Aripin KN, et al.

Free Radic Res, 2018 Sep;52(9):1000-1009.
PMID: 30079776 DOI: 10.1080/10715762.2018.1506877

Ageing is associated with increased oxidative stress accompanied by cognitive decline. The aim of this study was to evaluate oxidative stress biomarkers and their possible relationship with cognitive performances during ageing among the Malay population. Approximately 160 healthy Malay adults aged between 28 and 79 years were recruited around Selangor and Klang Valley. Cognitive function was assessed by Montreal Cognitive Assessment (MoCA), forward digit span (FDS), backward digit span (BDS), digit symbol, Rey Auditory Verbal Learning Test immediate recalled [RAVLT(I)] and delayed recalled [RAVLT(D)], and visual reproduction immediate recalled (VR-I) and delayed recalled (VR-II). DNA damage, plasma protein carbonyl and malondialdehyde (MDA) levels were also determined. Cognitive function test showed significant lower scores of MoCA, BDS, RAVLT(I), RAVLT(D), digit symbol, VR-I, and VR-II in the older age group (60 years old) compared with the 30-, 40-, and 50-year-old group. The extent of DNA damage was sequential with age: 60 > 50 > 40 > 30, whereas protein carbonyl was higher in 40-, 50-, and 60-year-old groups compared with the youngest group (30 years old). However, the MDA level was observed unchanged in all age groups. Approximately 21.88% of the participants had cognitive impairment. Multiple logistic regression analysis revealed that DNA damage and protein carbonyl levels are predictors for cognitive impairment in healthy Malays. In conclusion, cognitive decline occurred in healthy adult Malay population at an early age of 30 years old with corresponding higher DNA damage and protein oxidation.
Fulltext Proteome profiling in the hippocampus, medial prefrontal cortex, and striatum of aging rat

Hamezah HS, Durani LW, Yanagisawa D, Ibrahim NF, Aizat WM, Bellier JP, et al.

Exp Gerontol, 2018 Oct 01;111:53-64.
PMID: 29981398 DOI: 10.1016/j.exger.2018.07.002

Decrease in multiple functions occurs in the brain with aging, all of which can contribute to age-related cognitive and locomotor impairments. Brain atrophy specifically in hippocampus, medial prefrontal cortex (mPFC), and striatum, can contribute to this age-associated decline in function. Our recent metabolomics analysis showed age-related changes in these brain regions. To further understand the aging processes, analysis using a proteomics approach was carried out. This study was conducted to identify proteome profiles in the hippocampus, mPFC, and striatum of 14-, 18-, 23-, and 27-month-old rats. Proteomics analysis using ultrahigh performance liquid chromatography coupled with Q Exactive HF Orbitrap mass spectrometry identified 1074 proteins in the hippocampus, 871 proteins in the mPFC, and 241 proteins in the striatum. Of these proteins, 97 in the hippocampus, 25 in mPFC, and 5 in striatum were differentially expressed with age. The altered proteins were classified into three ontologies (cellular component, molecular function, and biological process) containing 44, 38, and 35 functional groups in the hippocampus, mPFC, and striatum, respectively. Most of these altered proteins participate in oxidative phosphorylation (e.g. cytochrome c oxidase and ATP synthase), glutathione metabolism (e.g. peroxiredoxins), or calcium signaling pathway (e.g. protein S100B and calmodulin). The most prominent changes were observed in the oldest animals. These results suggest that alterations in oxidative phosphorylation, glutathione metabolism, and calcium signaling pathway are involved in cognitive and locomotor impairments in aging.
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.

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