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  1. Fulltext REST Targets JAK-STAT and HIF-1 Signaling Pathways in Human Down Syndrome Brain and Neural Cells
    Huang T, Fakurazi S, Cheah PS, Ling KH
    Int J Mol Sci, 2023 Jun 10;24(12).
    PMID: 37373133 DOI: 10.3390/ijms24129980
    Down syndrome (DS) is the most frequently diagnosed chromosomal disorder of chromosome 21 (HSA21) aneuploidy, characterized by intellectual disability and reduced lifespan. The transcription repressor, Repressor Element-1 Silencing Transcription factor (REST), which acts as an epigenetic regulator, is a crucial regulator of neuronal and glial gene expression. In this study, we identified and investigated the role of REST-target genes in human brain tissues, cerebral organoids, and neural cells in Down syndrome. Gene expression datasets generated from healthy controls and DS samples of human brain tissues, cerebral organoids, NPC, neurons, and astrocytes were retrieved from the Gene Ontology (GEO) and Sequence Read Archive (SRA) databases. Differential expression analysis was performed on all datasets to produce differential expression genes (DEGs) between DS and control groups. REST-targeted DEGs were subjected to functional ontologies, pathways, and network analyses. We found that REST-targeted DEGs in DS were enriched for the JAK-STAT and HIF-1 signaling pathways across multiple distinct brain regions, ages, and neural cell types. We also identified REST-targeted DEGs involved in nervous system development, cell differentiation, fatty acid metabolism and inflammation in the DS brain. Based on the findings, we propose REST as the critical regulator and a promising therapeutic target to modulate homeostatic gene expression in the DS brain.
    Matched MeSH terms: Hypoxia-Inducible Factor 1/metabolism
  2. Hypoxia and Proton microbeam: Role of Gap Junction Intercellular Communication in Inducing Bystander Responses on Human Lung Cancer Cells and Normal Cells
    Autsavapromporn N, Kobayashi A, Liu C, Jaikang C, Tengku Ahmad TA, Oikawa M, et al.
    Radiat Res, 2022 Feb 01;197(2):122-130.
    PMID: 34634126 DOI: 10.1667/RADE-21-00112.1
    Radiation-induced bystander effect (RIBE) has been identified as an important contributing factor to tumor resistance and normal tissue damage. However, the RIBE in cancer and normal cells under hypoxia remain unclear. In this study, confluent A549 cancer and WI-38 normal cells were subjected to condition of hypoxia or normoxia, before exposure to high-LET protons microbeam. After 6 h incubation, cells were harvested and assayed for colony formation, micronucleus formation, chromosome aberration and western blotting. Our results show that there were differences of RIBE in bystander A549 and WI-38 cells under hypoxia and normoxia. The differences were also observed in the roles of HIF-1α expression in bystander A549 and WI-38 cells under both conditions. Furthermore, inhibition of gap junction intercellular communication (GJIC) showed a decrease in toxicity of hypoxia-treated bystander A549 cells, but increased in bystander WI-38 cells. These findings clearly support that GJIC protection of bystander normal cells from toxicity while enhancing in bystander cancer cells. Together, the data show a promising strategy for high-LET radiation in designing an entire new line of drugs, either increase or restore GJIC in bystander cancer cells which in turn leads to enhancement of radiation accuracy for treatment of hypoxic tumors.
    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
  3. Fulltext Hypoxia-inducible factor 1 signalling, metabolism and its therapeutic potential in cardiovascular disease
    Sousa Fialho MDL, Abd Jamil AH, Stannard GA, Heather LC
    Biochim Biophys Acta Mol Basis Dis, 2019 04 01;1865(4):831-843.
    PMID: 30266651 DOI: 10.1016/j.bbadis.2018.09.024
    Cardiovascular disease (CVD) accounts for the largest number of deaths worldwide, necessitating the development of novel treatments and prevention strategies. Given the huge energy demands placed on the heart, it is not surprising that changes in energy metabolism play a key role in the development of cardiac dysfunction in CVD. A reduction in oxygen delivery to the heart, hypoxia, is sensed and responded to by the hypoxia-inducible factor (HIF) and its family of proteins, by regulating the oxygen-dependent signalling cascade and subsequent response. Hypoxia is one of the main drivers of metabolic change in ischaemic disease and myocardial infarction, and we therefore suggest that HIF may be an attractive therapeutic target. In this review, we assess cardiac energy metabolism in health and disease, and how these can be regulated by HIF-1α activation. We then present an overview of research in the field of hypoxia-mimetic drugs recently developed in other treatment fields, which provide insight into the potential of systemic HIF-1α activation therapy for treating the heart.
    Matched MeSH terms: Hypoxia-Inducible Factor 1/metabolism*
  4. Fulltext HIF-1-Independent Mechanisms Regulating Metabolic Adaptation in Hypoxic Cancer Cells
    Lee SH, Golinska M, Griffiths JR
    Cells, 2021 Sep 09;10(9).
    PMID: 34572020 DOI: 10.3390/cells10092371
    In solid tumours, cancer cells exist within hypoxic microenvironments, and their metabolic adaptation to this hypoxia is driven by HIF-1 transcription factor, which is overexpressed in a broad range of human cancers. HIF inhibitors are under pre-clinical investigation and clinical trials, but there is evidence that hypoxic cancer cells can adapt metabolically to HIF-1 inhibition, which would provide a potential route for drug resistance. Here, we review accumulating evidence of such adaptions in carbohydrate and creatine metabolism and other HIF-1-independent mechanisms that might allow cancers to survive hypoxia despite anti-HIF-1 therapy. These include pathways in glucose, glutamine, and lipid metabolism; epigenetic mechanisms; post-translational protein modifications; spatial reorganization of enzymes; signalling pathways such as Myc, PI3K-Akt, 2-hyxdroxyglutarate and AMP-activated protein kinase (AMPK); and activation of the HIF-2 pathway. All of these should be investigated in future work on hypoxia bypass mechanisms in anti-HIF-1 cancer therapy. In principle, agents targeted toward HIF-1β rather than HIF-1α might be advantageous, as both HIF-1 and HIF-2 require HIF-1β for activation. However, HIF-1β is also the aryl hydrocarbon nuclear transporter (ARNT), which has functions in many tissues, so off-target effects should be expected. In general, cancer therapy by HIF inhibition will need careful attention to potential resistance mechanisms.
    Matched MeSH terms: Hypoxia-Inducible Factor 1/metabolism*
  5. Fulltext [Zinc induces normoxic accumulation of transcriptionally active hypoxia-inducible factor 1-alpha in mammary epithelial cells]
    Lee SY, Mustafa S, Ching YW, Shafee N
    Mol Biol (Mosk), 2017 3 3;51(1):104-110.
    PMID: 28251972 DOI: 10.7868/S0026898417010116
    Both zinc and the α-subunit of hypoxia-inducible factor (HIF-1α) play important roles in the remodelling of mammary gland tissues. In the present study, we examined the level and the transcriptional activity of HIF-1α in mammary cells upon zinc treatment. In MCF-7 mammary adenocarcinoma and MCF-10A mammary epithelial cell lines, the toxicity levels of zinc differ. Interestingly, both cell lines overexpress HIF-1α following zinc treatment. As it was evident from an up-regulation of its specific target gene CA9 that encodes carbonic anhydrase IX, the stabilized HIF-1α translocated to the nucleus and was transcriptionally active. Hence, we conclude that zinc causes normoxic accumulation of transcriptionally active HIF-1α by interfering with its post-translational regulation.
    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit/genetics; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism*
  6. Hypoxia affects cellular responses to plant extracts
    Liew SY, Stanbridge EJ, Yusoff K, Shafee N
    J Ethnopharmacol, 2012 Nov 21;144(2):453-6.
    PMID: 23022321 DOI: 10.1016/j.jep.2012.09.024
    Microenvironmental conditions contribute towards varying cellular responses to plant extract treatments. Hypoxic cancer cells are known to be resistant to radio- and chemo-therapy. New therapeutic strategies specifically targeting these cells are needed. Plant extracts used in Traditional Chinese Medicine (TCM) can offer promising candidates. Despite their widespread usage, information on their effects in hypoxic conditions is still lacking. In this study, we examined the cytotoxicity of a series of known TCM plant extracts under normoxic versus hypoxic conditions.
    Matched MeSH terms: Hypoxia-Inducible Factor 1/metabolism*
  7. Associations between hypoxia-inducible factor-1alpha (HIF-1alpha) gene polymorphisms and risk of developing breast cancer
    Naidu R, Har YC, Taib NA
    Neoplasma, 2009;56(5):441-7.
    PMID: 19580347
    The C1772T, G1790A and C111A polymorphisms of Hypoxia-inducible factor-1alpha (HIF-1alpha) gene were analyzed in a hospital-based Malaysian population using PCR-RFLP method. Genomic DNA was extracted from the blood samples collected from 410 breast cancer patients and 275 normal and healthy women. We investigated the association between HIF-1alpha polymorphisms and breast cancer risk, and clinico-pathological parameters in the population. The genotype and allele frequencies of C1772T (P=0.0093 vs P=0.0024) polymorphism were significantly different between the breast cancer cases and normal subjects but similar association was not observed for G1790A (P>0.05) and C111A (P>0.05) polymorphisms, respectively. Women who were CT heterozygotes (OR=1.51; 95% CI, 1.01-2.25), TT homozygotes (OR=4.03; 95% CI, 1.09-17.60) and carriers of T allele genotype (OR=1.65; 95% CI, 1.13-2.43) were significantly associated with increased risk of breast cancer. Significant relationship was observed also between T allele and breast cancer risk (OR=1.69; 95% CI, 1.20-2.40). Clinico-pathological analysis showed that 1772T allele genotype was significantly associated with nodal metastases (P=0.0478) but independent of ER status, tumor grade and patients' age (P>0.05). Our observations suggest that the polymorphic allele of C1772T may be associated with increased risk of developing breast cancer, and presence of 1772T allele may be a useful genetic marker for tumor prognosis.
    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit/genetics*
  8. Impact of low oxygen tension on stemness, proliferation and differentiation potential of human adipose-derived stem cells
    Choi JR, Pingguan-Murphy B, Wan Abas WA, Noor Azmi MA, Omar SZ, Chua KH, et al.
    Biochem Biophys Res Commun, 2014 May 30;448(2):218-24.
    PMID: 24785372 DOI: 10.1016/j.bbrc.2014.04.096
    Adipose-derived stem cells (ASCs) have been found adapted to a specific niche with low oxygen tension (hypoxia) in the body. As an important component of this niche, oxygen tension has been known to play a critical role in the maintenance of stem cell characteristics. However, the effect of O2 tension on their functional properties has not been well determined. In this study, we investigated the effects of O2 tension on ASCs stemness, differentiation and proliferation ability. Human ASCs were cultured under normoxia (21% O2) and hypoxia (2% O2). We found that hypoxia increased ASC stemness marker expression and proliferation rate without altering their morphology and surface markers. Low oxygen tension further enhances the chondrogenic differentiation ability, but reduces both adipogenic and osteogenic differentiation potential. These results might be correlated with the increased expression of HIF-1α under hypoxia. Taken together, we suggest that growing ASCs under 2% O2 tension may be important in expanding ASCs effectively while maintaining their functional properties for clinical therapy, particularly for the treatment of cartilage defects.
    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit/genetics; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
  9. Fulltext Quantitative MS-Based Proteomics: Comparing the MCF-7 Cellular Response to Hypoxia and a 2-Oxoglutarate Analogue
    Bush JT, Chan MC, Mohammed S, Schofield CJ
    Chembiochem, 2020 06 02;21(11):1647-1655.
    PMID: 31919953 DOI: 10.1002/cbic.201900719
    The hypoxia-inducible factors (HIFs) are key transcription factors in determining cellular responses involving alterations in protein levels in response to limited oxygen availability in animal cells. 2-Oxoglutarate-dependent oxygenases play key roles in regulating levels of HIF and its transcriptional activity. We describe MS-based proteomics studies in which we compared the results of subjecting human breast cancer MCF-7 cells to hypoxia or treating them with a cell-penetrating derivative (dimethyl N-oxalylglycine; DMOG) of the stable 2OG analogue N-oxalylglycine. The proteomic results are consistent with reported transcriptomic analyses and support the proposed key roles of 2OG-dependent HIF prolyl- and asparaginyl-hydroxylases in the hypoxic response. Differences between the data sets for hypoxia and DMOG might reflect context-dependent effects or HIF-independent effects of DMOG.
    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit/genetics*; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
  10. Fulltext PI3K/Akt activity has variable cell-specific effects on expression of HIF target genes, CA9 and VEGF, in human cancer cell lines
    Shafee N, Kaluz S, Ru N, Stanbridge EJ
    Cancer Lett, 2009 Sep 8;282(1):109-15.
    PMID: 19342157 DOI: 10.1016/j.canlet.2009.03.004
    The phosphatidylinositol 3-kinase/Akt (PI3K) pathway regulates hypoxia-inducible factor (HIF) activity. Higher expression of HIF-1alpha and carbonic anhydrase IX (CAIX), a hypoxia-inducible gene, in HT10806TG fibrosarcoma cells (mutant N-ras allele), compared to derivative MCH603 cells (deleted mutant N-ras allele), correlated with increased PI3K activity. Constitutive activation of the PI3K pathway in MCH603/PI3K(act) cells increased HIF-1alpha but, surprisingly, decreased CAIX levels. The cell-type specific inhibitory effect on CAIX was confirmed at the transcriptional level whereas epigenetic modifications of CA9 were ruled out. In summary, our data do not substantiate the generalization that PI3K upregulation leads to increased HIF activity.
    Matched MeSH terms: Hypoxia-Inducible Factor 1/physiology*; Hypoxia-Inducible Factor 1, alpha Subunit/genetics*
  11. Hypoxia-inducible factor-1α as a predictive marker in pre-eclampsia
    Akhilesh M, Mahalingam V, Nalliah S, Ali RM, Ganesalingam M, Haleagrahara N
    Biomed Rep, 2013 Mar;1(2):257-258.
    PMID: 24648931
    The aim of this study was to determine whether or not the increased levels of hypoxia-inducible factor-1α (HIF-1α) could be used to demonstrate failed placentation in pre-eclamptic mothers. Twenty pregnant females with (pre-eclampsia group) or without pre-eclampsia (control group) were included in the present study. Antenatal and post-delivery HIF-1α transcription factor levels were measured. A significant increase was observed in the HIF-1α levels in the pre- and post-natal pre-eclampsia mothers. The findings suggest that the levels of HIF-1α in the blood of mothers with pre-eclampsia decrease after delivery of the placenta. The results confirm that there is increased HIF-1α in pre-eclampsia and a steady increase in the levels of HIF-1α could be commensurate with the possibility of a patient developing pre-eclampsia at a later trimester.
    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit
  12. The role of mTOR signalling pathway in hypoxia-induced cognitive impairment
    Abdo Qaid EY, Zulkipli NN, Zakaria R, Ahmad AH, Othman Z, Muthuraju S, et al.
    Int J Neurosci, 2021 May;131(5):482-488.
    PMID: 32202188 DOI: 10.1080/00207454.2020.1746308
    Hypoxia has been associated with cognitive impairment. Many studies have investigated the role of mTOR signalling pathway in cognitive functions but its role in hypoxia-induced cognitive impairment remains controversial. This review aimed to elucidate the role of mTOR in the mechanisms of cognitive impairment that may pave the way towards the mechanistic understanding and therapeutic intervention of hypoxia-induced cognitive impairment. mTORC1 is normally regulated during mild or acute hypoxic exposure giving rise to neuroprotection, whereas it is overactivated during severe or chronic hypoxia giving rise to neuronal cells death. Thus, it is worth exploring the possibility of maintaining normal mTORC1 activity and thereby preventing cognitive impairment during severe or chronic hypoxia.
    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit/metabolism*
  13. Fulltext Inhibition of Raf-MEK-ERK and hypoxia pathways by Phyllanthus prevents metastasis in human lung (A549) cancer cell line
    Lee SH, Jaganath IB, Manikam R, Sekaran SD
    BMC Complement Altern Med, 2013 Oct 20;13:271.
    PMID: 24138815 DOI: 10.1186/1472-6882-13-271
    BACKGROUND: Lung cancer constitutes one of the malignancies with the greatest incidence and mortality rates with 1.6 million new cases and 1.4 million deaths each year. Prognosis remains poor due to deleterious development of multidrug resistance resulting in less than 15% lung cancer patients reaching five years survival. We have previously shown that Phyllanthus induced apoptosis in conjunction with its antimetastastic action. In the current study, we aimed to determine the signaling pathways utilized by Phyllanthus to exert its antimetastatic activities.

    METHODS: Cancer 10-pathway reporter array was performed to screen the pathways affected by Phyllanthus in lung carcinoma cell line (A549) to exert its antimetastatic effects. Results from this array were then confirmed with western blotting, cell cycle analysis, zymography technique, and cell based ELISA assay for human total iNOS. Two-dimensional gel electrophoresis was subsequently carried out to study the differential protein expressions in A549 after treatment with Phyllanthus.

    RESULTS: Phyllanthus was observed to cause antimetastatic activities by inhibiting ERK1/2 pathway via suppression of Raf protein. Inhibition of this pathway resulted in the suppression of MMP2, MMP7, and MMP9 expression to stop A549 metastasis. Phyllanthus also inhibits hypoxia pathway via inhibition of HIF-1α that led to reduced VEGF and iNOS expressions. Proteomic analysis revealed a number of proteins downregulated by Phyllanthus that were involved in metastatic processes, including invasion and mobility proteins (cytoskeletal proteins), transcriptional proteins (proliferating cell nuclear antigen; zinc finger protein), antiapoptotic protein (Bcl2) and various glycolytic enzymes. Among the four Phyllanthus species tested, P. urinaria showed the greatest antimetastatic activity.

    CONCLUSIONS: Phyllanthus inhibits A549 metastasis by suppressing ERK1/2 and hypoxia pathways that led to suppression of various critical proteins for A549 invasion and migration.

    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit/genetics; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
  14. Fulltext Newcastle disease virus degrades HIF-1α through proteasomal pathways independent of VHL and p53
    Abd-Aziz N, Stanbridge EJ, Shafee N
    J Gen Virol, 2016 Dec;97(12):3174-3182.
    PMID: 27902314 DOI: 10.1099/jgv.0.000623
    Newcastle disease virus (NDV) is a candidate agent for oncolytic virotherapy. Despite its potential, the exact mechanism of its oncolysis is still not known. Recently, we reported that NDV exhibited an increased oncolytic activity in hypoxic cancer cells. These types of cells negatively affect therapeutic outcome by overexpressing pro-survival genes under the control of the hypoxia-inducible factor (HIF). HIF-1 is a heterodimeric transcriptional factor consisting of a regulated α (HIF-1α) and a constitutive β subunit (HIF-1β). To investigate the effects of NDV infection on HIF-1α in cancer cells, the osteosarcoma (Saos-2), breast carcinoma (MCF-7), colon carcinoma (HCT116) and fibrosarcoma (HT1080) cell lines were used in the present study. Data obtained showed that a velogenic NDV infection diminished hypoxia-induced HIF-1α accumulation, leading to a decreased activation of its downstream target gene, carbonic anhydrase 9. This NDV-induced downregulation of HIF-1α occurred post-translationally and was partially abrogated by proteasomal inhibition. The process appeared to be independent of the tumour suppressor protein p53. These data revealed a correlation between NDV infection and HIF-1α downregulation, which highlights NDV as a promising agent to eliminate hypoxic cancer cells.
    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit/genetics; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism*
  15. Fulltext High throughput silencing identifies novel genes in endometrioid endometrial cancer
    Md Fuzi AA, Omar SZ, Mohamed Z, Mat Adenan NA, Mokhtar NM
    Taiwan J Obstet Gynecol, 2018 Apr;57(2):217-226.
    PMID: 29673664 DOI: 10.1016/j.tjog.2018.02.009
    OBJECTIVE: To validate the gene expression profile obtained from the previous microarray analysis and to further study the biological functions of these genes in endometrial cancer. From our previous study, we identified 621 differentially expressed genes in laser-captured microdissected endometrioid endometrial cancer as compared to normal endometrial cells. Among these genes, 146 were significantly up-regulated in endometrial cancer.

    MATERIALS AND METHODS: A total of 20 genes were selected from the list of up-regulated genes for the validation assay. The qPCR confirmed that 19 out of the 20 genes were up-regulated in endometrial cancer compared with normal endometrium. RNA interference (RNAi) was used to knockdown the expression of the upregulated genes in ECC-1 and HEC-1A endometrial cancer cell lines and its effect on proliferation, migration and invasion were examined.

    RESULTS: Knockdown of MIF, SOD2, HIF1A and SLC7A5 by RNAi significantly decreased the proliferation of ECC-1 cells (p < 0.05). Our results also showed that the knockdown of MIF, SOD2 and SLC7A5 by RNAi significantly decreased the proliferation and migration abilities of HEC-1A cells (p < 0.05). Moreover, the knockdown of SLC38A1 and HIF1A by RNAi resulted in a significant decrease in the proliferation of HEC1A cells (p < 0.05).

    CONCLUSION: We have identified the biological roles of SLC38A1, MIF, SOD2, HIF1A and SLC7A5 in endometrial cancer, which opens up the possibility of using the RNAi silencing approach to design therapeutic strategies for treatment of endometrial cancer.

    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit/genetics; Hypoxia-Inducible Factor 1, alpha Subunit/physiology
  16. Mesua ferrea stem bark extract induces apoptosis and inhibits metastasis in human colorectal carcinoma HCT 116 cells, through modulation of multiple cell signalling pathways
    Asif M, Shafaei A, Abdul Majid AS, Ezzat MO, Dahham SS, Ahamed MBK, et al.
    Chin J Nat Med, 2017 Jul;15(7):505-514.
    PMID: 28807224 DOI: 10.1016/S1875-5364(17)30076-6
    Considering the great potential of natural products as anticancer agents, the present study was designed to explore the molecular mechanisms responsible for anticancer activities of Mesua ferrea stem bark extract against human colorectal carcinoma. Based on MTT assay results, bioactive sub-fraction (SF-3) was selected for further studies using HCT 116 cells. Repeated column chromatography resulted in isolation of less active α-amyrin from SF-3, which was identified and characterized by GC-MS and HPLC methods. α-amyrin and betulinic acid contents of SF-3 were measured by HPLC methods. Fluorescent assays revealed characteristic apoptotic features, including cell shrinkage, nuclear condensation, and marked decrease in mitochondrial membrane potential in SF-3 treated cells. In addition, increased levels of caspases-9 and -3/7 levels were also observed in SF-3 treated cells. SF-3 showed promising antimetastatic properties in multiple in vitro assays. Multi-pathway analysis revealed significant down-regulation of WNT, HIF-1α, and EGFR with simultaneous up-regulation of p53, Myc/Max, and TGF-β signalling pathways in SF-3 treated cells. In addition, promising growth inhibitory effects were observed in SF-3 treated HCT 116 tumour spheroids, which give a hint about in vivo antitumor efficacy of SF-3 phytoconstituents. In conclusion, these results demonstrated that anticancer effects of SF-3 towards colon cancer are through modulation of multiple molecular pathways.
    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit/genetics; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
  17. Effect of 17β-estradiol on mediators involved in mesenchymal stromal cell trafficking in cell therapy of diabetes
    Mirzamohammadi S, Aali E, Najafi R, Kamarul T, Mehrabani M, Aminzadeh A, et al.
    Cytotherapy, 2015 Jan;17(1):46-57.
    PMID: 25457279 DOI: 10.1016/j.jcyt.2014.06.009
    Mesenchymal stromal cells (MSCs) have shown great promise for cell therapy of a wide range of diseases such as diabetes. However, insufficient viability of transplanted cells reaching to damaged tissues has limited their potential therapeutic effects. Expression of estrogen receptors on stem cells may suggest a role for 17β-estradiol (E2) in regulating some functions in these cells. There is evidence that E2 enhances homing of stem cells. Induction of hypoxia-inducible factor-1α (HIF-1α) by E2 and the profound effect of HIF-1α on migration of cells have previously been demonstrated. We investigated the effect of E2 on major mediators involved in trafficking and subsequent homing of MSCs both in vitro and in vivo in diabetic rats.
    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit/drug effects
  18. Development of an In Vitro Cardiac Ischemic Model Using Primary Human Cardiomyocytes
    Hafez P, Chowdhury SR, Jose S, Law JX, Ruszymah BHI, Mohd Ramzisham AR, et al.
    Cardiovasc Eng Technol, 2018 09;9(3):529-538.
    PMID: 29948837 DOI: 10.1007/s13239-018-0368-8
    Developing experimental models to study ischemic heart disease is necessary for understanding of biological mechanisms to improve the therapeutic approaches for restoring cardiomyocytes function following injury. The aim of this study was to develop an in vitro hypoxic/re-oxygenation model of ischemia using primary human cardiomyocytes (HCM) and define subsequent cytotoxic effects. HCM were cultured in serum and glucose free medium in hypoxic condition with 1% O2 ranging from 30 min to 12 h. The optimal hypoxic exposure time was determined using Hypoxia Inducible Factor 1α (HIF-1α) as the hypoxic marker. Subsequently, the cells were moved to normoxic condition for 3, 6 and 9 h to replicate the re-oxygenation phase. Optimal period of hypoxic/re-oxygenation was determined based on 50% mitochondrial injury via 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide assay and cytotoxicity via lactate dehydrogenase (LDH) assay. It was found that the number of cells expressing HIF-1α increased with hypoxic time and 3 h was sufficient to stimulate the expression of this marker in all the cells. Upon re-oxygenation, mitochondrial activity reduced significantly whereas the cytotoxicity increased significantly with time. Six hours of re-oxygenation was optimal to induce reversible cell injury. The injury became irreversible after 9 h as indicated by > 60% LDH leakage compared to the control group cultured in normal condition. Under optimized hypoxic reoxygenation experimental conditions, mesenchymal stem cells formed nanotube with ischemic HCM and facilitated transfer of mitochondria suggesting the feasibility of using this as a model system to study molecular mechanisms of myocardial injury and rescue.
    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
  19. Fulltext Electrospun deferoxamine nanofiber for diabetic wound healing
    Tracey Anastacia Jeckson, Sreenivas Patro Sisinthy, Neo Yun Ping
    Malaysian Journal of Medicine and Health Sciences, 2019;15(102):46-46.
    MyJurnal
    Introduction: Diabetic foot ulcer (DFU) is the most distressing complication of diabetes mellitus and often associated with risk of non-traumatic lower extremity amputations. Available formulations and wound dressings for DFU treatment are unfortunately less effective both on controlling and healing DFU. Issues commonly found are associated with providing an optimum environment which facilitates healing process; moist environment, effective oxygen exchange, preventing infection, controlling exudate and also patients compliance. The challenge is therefore to develop a novel drug delivery which address this unmet medical need for better wound treatment of chronic and slow healing DFU. This study aimed to develop a biomaterial based nanofibrous wound dressing formulation containing deferoxamine (DFO), which reported as a potential therapeutic approach to improve wound healing. Deferoxamine regulates the expression and increase stability of hypoxia-inducible factor-1α (HIF-1 α), growthfactor that crucial in wound repair, and thus increase neovascularization. Preparation and characterization of chosen polymers; chitosan/ alginate/polyvinyl alcohol (PVA) for nanofiber formulation will be carried out. Such biodegradable polymer nanofiber is a great benefit for drug delivery owing to its high surface area to volume ratio and high porosity which creates ideal environment to aid in wound healing. Methods: Nanofibers loaded DFO will be fabricated by electrospinning
    method that utilizes electrostatic force to produce fine fibers from the polymeric solution. Results: Various polymers concentrations and ratios are investigated to obtain the desired fibers characteristics. The selected optimized DFO nanofibers will be studied for its efficacy in wound healing through in-vivo animal studies. Conclusion: The proposed formulation would be an ideal low cost novel wound dressing with improved healing potential for efficient treatment
    of diabetic foot ulcer.
    Matched MeSH terms: Hypoxia-Inducible Factor 1, alpha Subunit
  20. Fulltext Garcinia subelliptica Merr. (Fukugi): A multipurpose coastal tree with promising medicinal properties
    Inoue T, Kainuma M, Baba K, Oshiro N, Kimura N, Chan EW
    J Intercult Ethnopharmacol, 2017 Jan 3;6(1):121-127.
    PMID: 28163970 DOI: 10.5455/jice.20161229060034
    In this short review, the current knowledge on the botany, ecology, uses, and medicinal properties of the multipurpose Garcinia subelliptica (Fukugi) is updated. As yet, there are no reviews on this indigenous and heritage coastal tree species of the Ryukyu Islands in Japan, which has ethnocultural, ecological, and pharmacological significance. Planted by the Okinawan people some 300 years ago, Fukugi trees serve as windbreaks and accord protection against the destructive typhoons. The species has become a popular ornamental tree, and its bark has been used for dyeing fabrics. It forms part of the food chain for mammals and insects and serves as nesting sites for birds. Endowed with bioactive compounds of benzophenones, xanthones, biflavonoids, and triterpenoids, G. subelliptica possesses anticancer, anti-inflammatory, anti-tyrosinase, trypanocidal, antibacterial, DNA topoisomerase inhibitory, DNA strand scission, choline acetyltransferase enhancing, hypoxia-inducible factor-1 inhibitory, and antiandrogenic activities. Fukugetin and fukugiside are two novel biflavonoids named after the species. The chemical constituents of Fukugi fruits when compared with those of mangosteen yielded interesting contrasts.
    Matched MeSH terms: Hypoxia-Inducible Factor 1
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