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  1. Yelumalai, S., Jones, C., Coward, K.
    JUMMEC, 2013;16(2):1-6.
    MyJurnal
    Assisted Reproductive Technology (ART) is a suite of laboratory techniques designed to rescue infertile phenotypes. While ART has led to the birth of 5 million ART babies worldwide, success rates rarely exceed 40%. One potential factor for this could be iatrogenic (‘clinician-induced’) damage to critical sperm proteins, such as phospholipase C zeta (PLCζ) and protamine, which are fundamental for oocyte activation and sperm DNA integrity, respectively. This report describes how we have begun to investigate the adverse effects of ART techniques upon these key sperm proteins. We also describe the pathway taken by Miss Suseela Yelumalai to acquire a scholarship from the Malaysian Government and her postgraduate experience at the University of Oxford. We introduce the facilities and learning opportunities available at the Institute of Reproductive Sciences (IRS) which houses Dr Kevin Coward’s research laboratory, and finally, highlight the potential for collaborative development between the Universities of Oxford and Malaya.
  2. Yelumalai S, Muniandy S, Zawiah Omar S, Qvist R
    J Clin Biochem Nutr, 2010 Nov;47(3):191-7.
    PMID: 21103027 DOI: 10.3164/jcbn.10-27
    Preeclampsia (PE) is a major contributor to maternal and fetal mortality. The cause of preeclampsia remains unclear, but oxidative stress on the endothelium leading to endothelial dysfunction is said to be the root cause of the disease. The aim of this study was to measure and determine the plasma levels of key angiogenic factors in pregnancy as an indicator for the early onset of preeclampsia in pregnancy. Plasma levels of circulating a soluble fms like tyrosine kinase-1 (sFlt-1), an anti-angiogenic factor, vascular endothelial growth factor (VEGF) and placental growth factor (PIGF), both pro-angiogenic factors were analyzed in normal pregnant Malaysian women (control group, n = 34), women with pregnant induced hypertension (PIH, n = 34) and women with preeclampsia (PE, n = 34) all at three gestational ages, 24-28 weeks (early pregnancy: EP), 32-36 weeks (late pregnancy: LP) and 6 weeks after delivery (postpartum: PN). The plasma levels of angiogenic factors were determined by ELISA. sFlt-1 levels were elevated in PIH and PE patients as compared to controls. PIGF and VEGF were significantly decreased in PIH and PE as compared to the controls. These results suggest that elevated concentration of sFlt-1 and suppressed levels of PIGF and VEGF may contribute to the development of hypertension in pregnancy which precedes preeclampsia.
  3. Yelumalai S, Giribabu N, Karim K, Omar SZ, Salleh NB
    Arch Med Sci, 2019 Jan;15(1):240-249.
    PMID: 30697276 DOI: 10.5114/aoms.2018.81038
    Introduction: Diabetes mellitus (DM) has been associated with sperm damage. In view of the fact that quercetin possesses antioxidant and anti-inflammatory activities, this compound may help to protect sperm against damage in DM. In this study, in-vivo effects of quercetin on sperm parameters in DM were investigated.

    Material and methods: Quercetin (10, 25 and 50 mg/kg/b.w.) was given orally to streptozotocin-nicotinamide induced adult male diabetic rats for 28 days. Following treatment completion, rats were sacrificed and sperm were harvested from the cauda epididymis. Sperm count, motility, viability, hyperosmotic swelling (HOS) tail-coiled sperm and morphology were assessed. Levels of lipid peroxidation (LPO) and anti-oxidative enzymes (SOD, CAT and GPx) in sperm with and without H2O2 incubation were determined by biochemical assays. Expression levels of SOD, CAT and GPx mRNAs in sperm were evaluated by qPCR. Sperm DNA integrity was estimated by flow cytometry while expression levels of the inflammatory markers NF-κβ and TNF-α in sperm were determined by Western blotting.

    Results: In diabetic rats receiving quercetin, sperm count and motility, viability and HOS tail-coiled sperm increased (p < 0.05) while sperm with abnormal morphology decreased. Moreover, sperm SOD, CAT, GPx activities and their mRNA expression levels increased while sperm LPO, NF-κβ and TNF-α levels decreased. In normal and diabetic rat sperm incubated with H2O2, a further increase in MDA and further decreases in SOD, CAT and GPx were observed, and these were ameliorated by quercetin treatment.

    Conclusions: In-vivo administration of quercetin to diabetic rats helps to ameliorate sperm damage and improves sperm morphology and functions in DM.

  4. Khalil ASM, Giribabu N, Yelumalai S, Shahzad H, Kilari EK, Salleh N
    Life Sci, 2021 Aug 01;278:119605.
    PMID: 33989665 DOI: 10.1016/j.lfs.2021.119605
    Diabetes mellitus (DM) may lead to testicular-related infertility while Myristic acid (MA) is beneficial to lower hyperglycaemia. Thus, we hypothesized that MA could protect testes against hyperglycaemia-induced damage in DM. DM was induced in adult male rats by high-fat diet consumption for 12 weeks, accompanied by a single dose streptozotocin injection. Following DM confirmation, the rats were fed orally with 10 and 20 mg/kg body weight MA for 28 consecutive days. After completion of treatment, rats were sacrificed and blood, cauda epididymis and testes were harvested. Serum was separated, epididymal sperm was collected for analysis. Molecular studies of the testes were performed by qPCR, Western blotting and immunostaining. MA was found to protect the testes against oxidative stress via preventing the upregulation of RAGE, Keap1, and the downregulation of Nrf2, NQO1, HO1, SOD, CAT and GPx. MA also prevented increase in testicular inflammation and apoptosis, as indicated by low inflammatory (NF-κB p65, IKKβ, TNF-α, IL-1β and iNOS) and apoptosis (Bax and caspase-9), but high anti-apoptosis (Bcl-2) markers' levels. Besides, MA prevented the downregulation of testicular steroidogenic markers (3βHSD, 17βHSD, StAR, ARA-54 and CYP11A1). Sperm analysis revealed near normal sperm count, motility, viability, lower abnormal sperm morphology in diabetic rats received MA. MA also prevented the loss of germ cells via preventing the decreased in cell proliferative marker (PCNA) while maintaining near normal epithelial height, tubular and Leydig cell diameters in the testes in DM. MA protects the testes against damage in DM, thus maintaining spermatogenesis and steroidogenesis, consequently preserving male fertility in diabetes.
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