MyMedR

Displaying publications 1 - 20 of 32 in total

Abstract:

Sort:

Fulltext Effects of salvianolic acid A on β-amyloid mediated toxicity in Caenorhabditis elegans model of Alzheimer's disease

Yuen CW,, Halim MA,, Najimudin N,, Azzam G,

Journal of Biomedical and Clinical Sciences, 2020;5(1):1-7.
MyJurnal

Alzheimer’s disease (AD) is a brain disease attributed to the accumulation of extracellular senile plaques comprising β-amyloid peptide (Aβ). In this study, a transgenic Caenorhabditis elegans (C. elegans) containing the human beta amyloid Aβ42 gene which exhibited paralysis when expressed, was used to study the anti-paralysis effect of salvianolic acid A. Various concentrations ranging from 1 μg/ml to 100 μg/ml of salvianolic acid A were tested which exhibited the highest effect on the worm at the concentration of 100 μg/ml. For anti-aggregation effect, 14 μg/ml of salvianolic acid A (within 4 mg/ml of Danshen) showed a significant level of inhibition of the formation of Aβ fibrils. An amount of 100 μg/ml of salvianolic acid A had the potential in reducing the reactive oxygen species (ROS) but did not totally obliterate the ROS production in the worms. Salvianolic acid A was found to delay the paralysis of the transgenic C. elegans, decrease Aβ42 aggregation and decrease Aβ-induced oxidative stress.
Fulltext Assessment of Aedes albopictus reference genes for quantitative PCR at different stages of development

Dzaki N, Azzam G

PLoS One, 2018;13(3):e0194664.
PMID: 29554153 DOI: 10.1371/journal.pone.0194664

Members of the Aedes genus of mosquitoes are widely recognized as vectors of viral diseases. Ae.albopictus is its most invasive species, and are known to carry viruses such as Dengue, Chikugunya and Zika. Its emerging importance puts Ae.albopictus on the forefront of genetic interaction and evolution studies. However, a panel of suitable reference genes specific for this insect is as of now undescribed. Nine reference genes, namely ACT, eEF1-γ, eIF2α, PP2A, RPL32, RPS17, PGK1, ILK and STK were evaluated. Expression patterns of the candidate reference genes were observed in a total of seventeen sample types, separated by stage of development and age. Gene stability was inferred from obtained quantification data through three widely cited evaluation algorithms i.e. BestKeeper, geNorm, and NormFinder. No single gene showed a satisfactory degree of stability throughout all developmental stages. Therefore, we propose combinations of PGK and ILK for early embryos; RPL32 and RPS17 for late embryos, all four larval instars, and pupae samples; eEF1-γ with STK for adult males; eEF1-γ with RPS17 for non-blood fed females; and eEF1-γ with eIF2α for both blood-fed females and cell culture. The results from this study should be able to provide a more informed selection of normalizing genes during qPCR in Ae.albopictus.
Fulltext Drosophila melanogaster: Deciphering Alzheimer's Disease

Tan FHP, Azzam G

Malays J Med Sci, 2017 Mar;24(2):6-20.
PMID: 28894399 MyJurnal DOI: 10.21315/mjms2017.24.2.2

Alzheimer's disease (AD) is the most widespread neurodegenerative disorder worldwide. Its pathogenesis involves two hallmarks: aggregation of amyloid beta (Aβ) and occurrence of neurofibrillary tangles (NFTs). The mechanism behind the disease is still unknown. This has prompted the use of animal models to mirror the disease. The fruit fly, Drosophila melanogaster has garnered considerable attention as an organism to recapitulate human disorders. With the ability to monopolise a multitude of traditional and novel genetic tools, Drosophila is ideal for studying not only cellular aspects but also physiological and behavioural traits of human neurodegenerative diseases. Here, we discuss the use of the Drosophila model in understanding AD pathology and the insights gained in discovering drug therapies for AD.
Genome-wide identification and characterization of long intergenic noncoding RNAs in the regenerative flatworm Macrostomum lignano

Azlan A, Halim MA, Azzam G

Genomics, 2020 03;112(2):1273-1281.
PMID: 31381967 DOI: 10.1016/j.ygeno.2019.07.016

The free-living flatworm Macrostoma lignano (M. lignano) is an emerging model organism for aging and regeneration research. Long intergenic non-coding RNAs (lincRNAs) have important roles in many biological processes such as aging, stem cell maintenance and differentiation. However, to date, there is no systematic identification of lincRNAs in M. lignano. By using public RNA-seq data, we identified a total of 2547 lincRNA transcripts in M. lignano genome. We discovered that M. lignano lincRNAs shared many characteristics with other species such as shorter in length, lower GC content, and lower in expression compared to protein-coding genes. Unlike protein-coding genes, M. lignano lincRNAs showed higher tendency to be expressed in temporal and region-specific fashion. Additionally, co-expression network analysis and functional enrichment suggest that M. lignano lincRNAs have potential roles in regeneration. This study will provide important resources and pave the way for investigations on non-coding genes involved in aging and regeneration.
CTP synthase knockdown during early development distorts the nascent vertebral column and causes fluid retention in multiple tissues in zebrafish

Dzaki N, Wahab W, Azlan A, Azzam G

Biochem Biophys Res Commun, 2018 10 20;505(1):106-112.
PMID: 30241946 DOI: 10.1016/j.bbrc.2018.09.074

CTP Synthase (CTPS) is a metabolic enzyme that is recognized as a catalyst for nucleotide, phospholipid and sialoglycoprotein production. Though the structural characteristics and regulatory mechanisms of CTPS are well-understood, little is known regarding the extent of its involvement during the early developmental stages of vertebrates. Zebrafish carries two CTPS genes, annotated as ctps1a and ctps1b. Phylogenetic analyses show that both genes had diverged from homologues in the ancestral Actinopterygii, Oreochromis niloticus. Conservation of common CTPS-catalytic regions further establishes that both proteins are likely to be functionally similar to hsaCTPS. Here, we show that ctps1a is more critical throughout the initial period of embryonic development than ctps1b. The effects of concurrent partial knockdown are dependent on ctps1a vs ctps1b dosage ratios. When these are equally attenuated, abnormal phenotypes acquired prior to the pharyngula period disappear in hatchlings (48hpf); however, if either gene is more attenuated than the other, these only become more pronounced in advanced stages. Generally, disruption to normal ctps1a or ctps1b expression levels by morpholinos culminates in the distortion of the early spinal column as well as multiple-tissue oedema. Other effects include slower growth rates, increased mortality rates and impaired structural formation of the young fish's extremities. Embryos grown in DON, a glutamine-analogue drug and CTPS antagonist, also exhibit similar characteristics, thus strengthening the validity of the morpholino-induced phenotypes observed. Together, our results demonstrate the importance of CTPS for the development of zebrafish embryos, as well as a disparity in activity and overall importance amongst isozymes.
Argonaute: The executor of small RNA function

Azlan A, Dzaki N, Azzam G

J Genet Genomics, 2016 08 20;43(8):481-94.
PMID: 27569398 DOI: 10.1016/j.jgg.2016.06.002

The discovery of small non-coding RNAs - microRNA (miRNA), short interfering RNA (siRNA) and PIWI-interacting RNA (piRNA) - represents one of the most exciting frontiers in biology specifically on the mechanism of gene regulation. In order to execute their functions, these small RNAs require physical interactions with their protein partners, the Argonaute (AGO) family proteins. Over the years, numerous studies have made tremendous progress on understanding the roles of AGO in gene silencing in various organisms. In this review, we summarize recent progress of AGO-mediated gene silencing and other cellular processes in which AGO proteins have been implicated with a particular focus on progress made in flies, humans and other model organisms as compliment.
Fulltext Systematic identification and characterization of Aedes aegypti long noncoding RNAs (lncRNAs)

Azlan A, Obeidat SM, Yunus MA, Azzam G

Sci Rep, 2019 08 21;9(1):12147.
PMID: 31434910 DOI: 10.1038/s41598-019-47506-9

Long noncoding RNAs (lncRNAs) play diverse roles in biological processes. Aedes aegypti (Ae. aegypti), a blood-sucking mosquito, is the principal vector responsible for replication and transmission of arboviruses including dengue, Zika, and Chikungunya virus. Systematic identification and developmental characterisation of Ae. aegypti lncRNAs are still limited. We performed genome-wide identification of lncRNAs, followed by developmental profiling of lncRNA in Ae. aegypti. We identified a total of 4,689 novel lncRNA transcripts, of which 2,064, 2,076, and 549 were intergenic, intronic, and antisense respectively. Ae. aegypti lncRNAs share many characteristics with other species including low expression, low GC content, short in length, and low conservation. Besides, the expression of Ae. aegypti lncRNAs tend to be correlated with neighbouring and antisense protein-coding genes. A subset of lncRNAs shows evidence of maternal inheritance; hence, suggesting potential role of lncRNAs in early-stage embryos. Additionally, lncRNAs show higher tendency to be expressed in developmental and temporal specific manner. The results from this study provide foundation for future investigation on the function of Ae. aegypti lncRNAs.
Danshen (Salvia miltiorrhiza) water extract shows potential neuroprotective effects in Caenorhabditis elegans

Yuen CW, Murugaiyah V, Najimudin N, Azzam G

J Ethnopharmacol, 2021 Feb 10;266:113418.
PMID: 32991971 DOI: 10.1016/j.jep.2020.113418

ETHNOPHARMACOLOGICAL RELEVANCE: Danshen, is a traditional Chinese medicine obtained from the dried root and rhizome of Salvia miltiorrhiza Bunge. It is known to be used for neurological disorder including for Alzheimer's disease (AD). This study uncovers the effect of Danshen water extract on the Alzheimer's disease model of C.elegans.
MATERIAL AND METHODS: The composition of Danshen water extract was determined using (High Performance Liquid Chromatography (HPLC). Then Thioflavin T assay was used to determined if Danshen water extract could prevent the aggregation of amyloid-β peptide (Aβ). Alzheimer's disease C.elegans model was used to determine the effect of Danshen water extract. Finally, the reactive oxygen species (ROS) was determined using the 2,7-dichlorofuorescein diacetate method.
RESULTS: In this study, we found that standardized Danshen water extract that contains danshensu (1.26%), salvianolic acid A (0.35%) and salvianolic acid B (2.21%) are able to bind directly to Aβ and prevents it from aggregating. The IC50 for the inhibition of Aβ aggregation by Danshen water extract was 0.5 mg/ml. In the AD model of C.elegans, Danshen water extract managed to alleviates the paralysis phenotype. Furthermore, the administration of Danshen water extract displayed antioxidant properties toward the Aβ-induced oxidative stress.
CONCLUSIONS: AD is a widespread neurodegenerative disease attributed to the accumulation of extracellular plaques comprising Aβ. Danshen water extract could significantly reduce the progress of paralysis in the AD model of C. elegans, showing promising results with its antioxidant properties. It can be concluded that Danshen water extract could potentially serve as a therapeutic for AD.
Identification and characterization of long noncoding RNAs and their association with acquisition of blood meal in Culex quinquefasciatus

Azlan A, Halim MA, Mohamad F, Azzam G

Insect Sci, 2021 Aug;28(4):917-928.
PMID: 32621332 DOI: 10.1111/1744-7917.12847

The Southern house mosquito, Culex quinquefasciatus (Cx. quinquefasciatus) is an important vector that transmit multiple diseases including West Nile encephalitis, Japanese encephalitis, St. Louis encephalitis and lymphatic filariasis. Long noncoding RNAs (lncRNAs) involve in many biological processes such as development, infection, and virus-host interaction. However, there is no systematic identification and characterization of lncRNAs in Cx. quinquefasciatus. Here, we report the first lncRNA identification in Cx. quinquefasciatus. By using 31 public RNA-seq datasets, a total of 4763 novel lncRNA transcripts were identified, of which 3591, 569, and 603 were intergenic, intronic, and antisense respectively. Examination of genomic features revealed that Cx. quinquefasciatus shared similar characteristics with other species such as short in length, low GC content, low sequence conservation, and low coding potential. Furthermore, compared to protein-coding genes, Cx. quinquefasciatus lncRNAs had lower expression values, and tended to be expressed in temporally specific fashion. In addition, weighted correlation network and functional annotation analyses showed that lncRNAs may have roles in blood meal acquisition of adult female Cx. quinquefasciatus mosquitoes. This study presents the first systematic identification and analysis of Cx. quinquefasciatus lncRNAs and their association with blood feeding. Results generated from this study will facilitate future investigation on the function of Cx. quinquefasciatus lncRNAs.
Fulltext Evaluation of reference genes at different developmental stages for quantitative real-time PCR in Aedes aegypti

Dzaki N, Ramli KN, Azlan A, Ishak IH, Azzam G

Sci Rep, 2017 03 16;7:43618.
PMID: 28300076 DOI: 10.1038/srep43618

The mosquito Aedes aegypti (Ae. aegypti) is the most notorious vector of illness-causing viruses such as Dengue, Chikugunya, and Zika. Although numerous genetic expression studies utilizing quantitative real-time PCR (qPCR) have been conducted with regards to Ae. aegypti, a panel of genes to be used suitably as references for the purpose of expression-level normalization within this epidemiologically important insect is presently lacking. Here, the usability of seven widely-utilized reference genes i.e. actin (ACT), eukaryotic elongation factor 1 alpha (eEF1α), alpha tubulin (α-tubulin), ribosomal proteins L8, L32 and S17 (RPL8, RPL32 and RPS17), and glyceraldeyde 3-phosphate dehydrogenase (GAPDH) were investigated. Expression patterns of the reference genes were observed in sixteen pre-determined developmental stages and in cell culture. Gene stability was inferred from qPCR data through three freely available algorithms i.e. BestKeeper, geNorm, and NormFinder. The consensus rankings generated from stability values provided by these programs suggest a combination of at least two genes for normalization. ACT and RPS17 are the most dependably expressed reference genes and therefore, we propose an ACT/RPS17 combination for normalization in all Ae. aegypti derived samples. GAPDH performed least desirably, and is thus not a recommended reference gene. This study emphasizes the importance of validating reference genes in Ae. aegypti for qPCR based research.
Data on RNA-seq analysis of Drosophila melanogaster during ageing

Bajgiran M, Azlan A, Shamsuddin S, Azzam G, Halim MA

Data Brief, 2021 Oct;38:107413.
PMID: 34632013 DOI: 10.1016/j.dib.2021.107413

Ageing is defined as gradual decline of physiological, cellular and molecular state of an organism with time. The age-associated cell dysfunctions usually cause chronic diseases such as diabetes, cancers and other age-related diseases. Many of the genes and pathways involved in ageing are conserved in different species. These genes and pathways have been categorised into nine cellular and molecular hallmarks, namely, genomic instability, telomere attrition, loss of proteostasis, mitochondrial dysfunction, epigenetic alterations, deregulated nutrient sensing, stem cell exhaustion, cellular senescence and altered intercellular communication. Despite countless studies on ageing, the molecular mechanism of ageing is poorly understood. Here, we performed genome wide transcriptome mapping of ageing process in D. melanogaster. In which, transcriptomic analysis conducted on the 1 day and 60 days flies. Illumina Hiseq platform were used to generate raw data. Afterwards, further analysis including differential expression analysis, GO classification and KEGG pathway enrichment analysis were performed. The raw data were uploaded to SRA database and the BioProject ID is PRJNA718442. These data provide the basis for future research in order to discover the genes and pathways involved in ageing.
Fulltext CTP synthase: the hissing of the cellular serpent

Thangadurai S, Bajgiran M, Manickam S, Mohana-Kumaran N, Azzam G

Histochem Cell Biol, 2022 Dec;158(6):517-534.
PMID: 35881195 DOI: 10.1007/s00418-022-02133-w

CTP biosynthesis is carried out by two pathways: salvage and de novo. CTPsyn catalyzes the latter. The study of CTPsyn activity in mammalian cells began in the 1970s, and various fascinating discoveries were made regarding the role of CTPsyn in cancer and development. However, its ability to fit into a cellular serpent-like structure, termed 'cytoophidia,' was only discovered a decade ago by three independent groups of scientists. Although the self-assembly of CTPsyn into a filamentous structure is evolutionarily conserved, the enzyme activity upon this self-assembly varies in different species. CTPsyn is required for cellular development and homeostasis. Changes in the expression of CTPsyn cause developmental changes in Drosophila melanogaster. A high level of CTPsyn activity and formation of cytoophidia are often observed in rapidly proliferating cells such as in stem and cancer cells. Meanwhile, the deficiency of CTPsyn causes severe immunodeficiency leading to immunocompromised diseases caused by bacteria, viruses, and parasites, making CTPsyn an attractive therapeutic target. Here, we provide an overview of the role of CTPsyn in cellular and disease perspectives along with its potential as a drug target.
Fulltext Ectopic miR-975 induces CTP synthase directed cell proliferation and differentiation in Drosophila melanogaster

Woo WK, Dzaki N, Thangadurai S, Azzam G

Sci Rep, 2019 Apr 15;9(1):6096.
PMID: 30988367 DOI: 10.1038/s41598-019-42369-6

CTP synthase (CTPSyn) is an essential metabolic enzyme, synthesizing precursors required for nucleotides and phospholipids production. Previous studies have also shown that CTPSyn is elevated in various cancers. In many organisms, CTPSyn compartmentalizes into filaments called cytoophidia. In Drosophila melanogaster, only its isoform C (CTPSynIsoC) forms cytoophidia. In the fruit fly's testis, cytoophidia are normally seen in the transit amplification regions close to its apical tip, where the stem-cell niche is located, and development is at its most rapid. Here, we report that CTPSynIsoC overexpression causes the lengthening of cytoophidia throughout the entirety of the testicular body. A bulging apical tip is found in approximately 34% of males overexpressing CTPSynIsoC. Immunostaining shows that this bulged phenotype is most likely due to increased numbers of both germline cells and spermatocytes. Through a microRNA (miRNA) overexpression screen, we found that ectopic miR-975 concurrently increases both the expression levels of CTPSyn and the length of its cytoophidia. The bulging testes phenotype was also recovered at a penetration of approximately 20%. However, qPCR assays reveal that CTPSynIsoC and miR-975 overexpression each provokes a differential response in expression of a number of cancer-related genes, indicating that the shared CTPSyn upregulation seen in either case is likely the cause of observed testicular overgrowth. This study presents the first instance of consequences of miRNA-asserted regulation upon CTPSyn in D. melanogaster, and further reaffirms the enzyme's close ties to germline cells overgrowth.
MicroRNA regulation of CTP synthase and cytoophidium in Drosophila melanogaster

Dzaki N, Woo WK, Thangadurai S, Azzam G

Exp Cell Res, 2019 12 15;385(2):111688.
PMID: 31678212 DOI: 10.1016/j.yexcr.2019.111688

CTPsyn is a crucial metabolic enzyme which synthesizes CTP nucleotides. It has the extraordinary ability to compartmentalize into filaments termed cytoophidia. Though the structure is evolutionarily conserved across kingdoms, the mechanisms behind their formation remain unknown. MicroRNAs (miRNAs) are short single-stranded RNA capable of directing mRNA silencing and degradation. D. melanogaster has a high total gene count to miRNA gene number ratio, alluding to the possibility that CTPsyn too may come under their regulation. A thorough miRNA overexpression involving 123 miRNAs was conducted, followed by CTPsyn-specific staining upon cytoophidia-rich egg chambers. This revealed a small group of candidates which confer either a lengthening or truncating effect on cytoophidia, suggesting they may play a role in regulating CTPsyn. MiR-975 and miR-1014 are both cytoophidia-elongating, whereas miR-190 and miR-932 are cytoophidia-shortening. Though target prediction shows that miR-975 and miR-932 do indeed have binding sites on CTPsyn mRNA, in vitro assays instead revealed a low probability of this being true, instead indicating that the effects asserted by overexpressed miRNAs indirectly reach CTPsyn and its cytoophidia through the actions of middling elements. In silico target prediction and qPCR quantification indicated that, at least for miR-932 and miR-1014, these undetermined elements may be players in fat metabolism. This is the first study to thoroughly investigate miRNAs in connection to CTPsyn expression and activity in any species. The findings presented could serve as a basis for further queries into not only the fundamental aspects of the enzyme's regulation, but may uncover new facets of closely related pathways as well.
Behavioural Effects and RNA-seq Analysis of Aβ42-Mediated Toxicity in a Drosophila Alzheimer's Disease Model

Tan FHP, Azzam G, Najimudin N, Shamsuddin S, Zainuddin A

Mol Neurobiol, 2023 Aug;60(8):4716-4730.
PMID: 37145377 DOI: 10.1007/s12035-023-03368-x

Alzheimer's disease (AD) is the most common neurological ailment worldwide. Its process comprises the unique aggregation of extracellular senile plaques composed of amyloid-beta (Aβ) in the brain. Aβ42 is the most neurotoxic and aggressive of the Aβ42 isomers released in the brain. Despite much research on AD, the complete pathophysiology of this disease remains unknown. Technical and ethical constraints place limits on experiments utilizing human subjects. Thus, animal models were used to replicate human diseases. The Drosophila melanogaster is an excellent model for studying both physiological and behavioural aspects of human neurodegenerative illnesses. Here, the negative effects of Aβ42-expression on a Drosophila AD model were investigated through three behavioural assays followed by RNA-seq. The RNA-seq data was verified using qPCR. AD Drosophila expressing human Aβ42 exhibited degenerated eye structures, shortened lifespan, and declined mobility function compared to the wild-type Control. RNA-seq revealed 1496 genes that were differentially expressed from the Aβ42-expressing samples against the control. Among the pathways that were identified from the differentially expressed genes include carbon metabolism, oxidative phosphorylation, antimicrobial peptides, and longevity-regulating pathways. While AD is a complicated neurological condition whose aetiology is influenced by a number of factors, it is hoped that the current data will be sufficient to give a general picture of how Aβ42 influences the disease pathology. The discovery of molecular connections from the current Drosophila AD model offers fresh perspectives on the usage of this Drosophila which could aid in the discovery of new anti-AD medications.
p-Coumaric acid attenuates the effects of Aβ42 in vitro and in a Drosophila Alzheimer's disease model

Tan FHP, Najimudin N, Watanabe N, Shamsuddin S, Azzam G

Behav Brain Res, 2023 Aug 24;452:114568.
PMID: 37414223 DOI: 10.1016/j.bbr.2023.114568

Alzheimer's disease (AD) is the most common neurodegenerative condition in civilizations worldwide. The distinctive occurrence of amyloid-beta (Aβ) accumulation into insoluble fibrils is part of the disease pathophysiology with Aβ42 being the most toxic and aggressive Aβ species. The polyphenol, p-Coumaric acid (pCA), has been known to boost a number of therapeutic benefits. Here, pCA's potential to counteract the negative effects of Aβ42 was investigated. First, pCA was confirmed to reduce Aβ42 fibrillation using an in vitro activity assay. The compound was next examined on Aβ42-exposed PC12 neuronal cells and was found to significantly decrease Aβ42-induced cell mortality. pCA was then examined using an AD Drosophila melanogaster model. Feeding of pCA partially reversed the rough eye phenotype, significantly lengthened AD Drosophila's lifespan, and significantly enhanced the majority of the AD Drosophila's mobility in a sex-dependent manner. The findings of this study suggest that pCA may have therapeutic benefits for AD.
Fulltext Genome-wide identification of Aedes albopictus long noncoding RNAs and their association with dengue and Zika virus infection

Azlan A, Obeidat SM, Theva Das K, Yunus MA, Azzam G

PLoS Negl Trop Dis, 2021 01;15(1):e0008351.
PMID: 33481791 DOI: 10.1371/journal.pntd.0008351

The Asian tiger mosquito, Aedes albopictus (Ae. albopictus), is an important vector that transmits arboviruses such as dengue (DENV), Zika (ZIKV) and Chikungunya virus (CHIKV). Long noncoding RNAs (lncRNAs) are known to regulate various biological processes. Knowledge on Ae. albopictus lncRNAs and their functional role in virus-host interactions are still limited. Here, we identified and characterized the lncRNAs in the genome of an arbovirus vector, Ae. albopictus, and evaluated their potential involvement in DENV and ZIKV infection. We used 148 public datasets, and identified a total of 10, 867 novel lncRNA transcripts, of which 5,809, 4,139, and 919 were intergenic, intronic and antisense respectively. The Ae. albopictus lncRNAs shared many characteristics with other species such as short length, low GC content, and low sequence conservation. RNA-sequencing of Ae. albopictus cells infected with DENV and ZIKV showed that the expression of lncRNAs was altered upon virus infection. Target prediction analysis revealed that Ae. albopictus lncRNAs may regulate the expression of genes involved in immunity and other metabolic and cellular processes. To verify the role of lncRNAs in virus infection, we generated mutations in lncRNA loci using CRISPR-Cas9, and discovered that two lncRNA loci mutations, namely XLOC_029733 (novel lncRNA transcript id: lncRNA_27639.2) and LOC115270134 (known lncRNA transcript id: XR_003899061.1) resulted in enhancement of DENV and ZIKV replication. The results presented here provide an important foundation for future studies of lncRNAs and their relationship with virus infection in Ae. albopictus.
Lactobacillus probiotics improved the gut microbiota profile of a Drosophila melanogaster Alzheimer's disease model and alleviated neurodegeneration in the eye

Tan FHP, Liu G, Lau SA, Jaafar MH, Park YH, Azzam G, et al.

Benef Microbes, 2020 Feb 19;11(1):79-89.
PMID: 32066253 DOI: 10.3920/BM2019.0086

Alzheimer's disease (AD) is a progressive disease and one of the most common forms of neurodegenerative disorders. Emerging evidence is supporting the use of various strategies that modulate gut microbiota to exert neurological and psychological changes. This includes the utilisation of probiotics as a natural and dietary intervention for brain health. Here, we showed the potential AD-reversal effects of Lactobacillus probiotics through feeding to our Drosophila melanogaster AD model. The administration of Lactobacillus strains was able to rescue the rough eye phenotype (REP) seen in AD-induced Drosophila, with a more prominent effect observed upon the administration of Lactobacillus plantarum DR7 (DR7). Furthermore, we analysed the gut microbiota of the AD-induced Drosophila and found elevated levels of Wolbachia. The administration of DR7 restored the gut microbiota diversity of AD-induced Drosophila with a significant reduction in Wolbachia's relative abundance, accompanied by an increase of Stenotrophomonas and Acetobacter. Through functional predictive analyses, Wolbachia was predicted to be positively correlated with neurodegenerative disorders, such as Parkinson's, Huntington's and Alzheimer's diseases, while Stenotrophomonas was negatively correlated with these neurodegenerative disorders. Altogether, our data exhibited DR7's ability to ameliorate the AD effects in our AD-induced Drosophila. Thus, we propose that Wolbachia be used as a potential biomarker for AD.
A transcriptomic (RNA-seq) analysis of Drosophila melanogaster adult testes overexpressing microRNA-2b-1

Manickam S, Thangadurai S, Azlan A, Amin Z, Azzam G, Halim MA

Data Brief, 2022 Dec;45:108748.
PMID: 36426000 DOI: 10.1016/j.dib.2022.108748

MicroRNAs (miRNAs) are short non-coding single-stranded RNAs with approximately 22 nucleotides in length that negatively regulate the mRNA translation of a target gene. MiR-2b-1 belongs to the largest miR-2 family in Drosophila melanogaster with 8 members and this miRNA family is conserved in invertebrates. miRNAs play key roles in gene regulation, cell proliferation, cell death, cell differentiation and cell developmental homeostasis in multicellular organisms. Its role in various human diseases is continuously being studied. miRNAs also found out to be crucial in maintaining stem cell niche in D. melanogaster gonads. We have identified that ectopic overexpression of miR-2b-1 of D. melanogaster causes testicular bulging (a tumour like phenotype) in 3-5 days old adult flies. Hence, we have performed a transcriptomic (RNA-seq) analysis to understand the role of miR-2b-1 in the development, maintenance, and differentiation of D. melanogaster adult testis stem cells. Data are available from GEO (accession number GSE211399).
Ethyl caffeate ameliorated amyloid-beta42 protein-associated toxicity in PC12 cells and Drosophila melanogaster

Tan FHP, Hadri NAB, Najimudin N, Watanabe N, Azzam G

Geriatr Gerontol Int, 2021 Dec;21(12):1125-1130.
PMID: 34699118 DOI: 10.1111/ggi.14296

AIM: Alzheimer's disease (AD) is the most pervasive neurodegenerative disorder in societies globally. Till now, the mechanism behind this disease is still equivocal. Amyloid-beta42 protein (Aβ42), the most toxic and aggressive Aβ species, is the main focus of this study. The naturally occurring ethyl caffeate (EC) is associated with various medicinal properties. Here, EC was tested for its protective properties against Aβ42's toxic effects.
METHODS: As treatment of Aβ42 has been shown to cause neuronal cell death, EC was first screened with Aβ42-incubated PC12 neuronal cells. Next, the compound was tested on the Drosophila melanogaster AD model using the rough eye phenotype assay, lifespan assay and negative geotaxis assay.
RESULTS: EC ameliorated PC12 cells from cell death linked to Aβ42 exposure. Using Drosophila expressing human Aβ42, feeding of EC was able to partially rescue the rough eye phenotype, lengthen the lifespan of AD Drosophila and enhanced the mobility of middle-aged AD Drosophila.
CONCLUSION: Overall, the results of this study showed that EC might possess therapeutic properties for AD. Geriatr Gerontol Int 2021; 21: 1125-1130.

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links