Walaa Bayoumie El Gazzar

Dr. Walaa Bayoumie El Gazzar


Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 November 2018 in Cells
Verified
Journal Article
Open access
PDF file
NENesrine Ebrahim
Nesrine Ebrahim
IAInas Ahmed
Inas Ahmed
NNoha Hussien
Noha Hussien
ADArigue Dessouky
Arigue Dessouky
AFAyman Samir Farid
Ayman Samir Farid
DSDina Sabry
Dina Sabry
Background: Diabetic nephropathy (DN) is a serious complication of diabetes mellitus and a common cause of end-stage renal disease. Autophagy has a defensive role against kidney damage caused by hyperglycemia. Mesenchymal stem cell (MSC)-derived exosomes are currently considered as a new promising therapy for chronic renal injury. However, the renal-protective mechanism of exosomes on DN is not completely understood. We examined the potential role of MSC-derived exosomes for enhancement of autophagy activity and their effect on DN. In our study, we used five groups of rats: control; DN; DN treated with exosomes; DN treated with 3-methyladenine (3-MA) and chloroquine (inhibitors of autophagy); and DN treated with 3-methyladenine (3-MA), chloroquine, and exosome groups. We assessed renal function, morphology, and fibrosis. Moreover, ratios of the autophagy markers mechanistic target of rapamycin (mTOR), Beclin-1, light chain-3 (LC3-II), and LC3-II/LC3-I were detected. Additionally, electron microscopy was used for detection of autophagosomes. Results: Exosomes markedly improved renal function and showed histological restoration of renal tissues, with significant increase of LC3 and Beclin-1, and significant decrease of mTOR and fibrotic marker expression in renal tissue. All previous effects were partially abolished by the autophagy inhibitors chloroquine and 3-MA. Conclusion: We conclude that autophagy induction by exosomes could attenuate DN in a rat model of streptozotocin-induced diabetes mellitus.

10 September 2018 in Preprints.org
Verified
Preprint
Open access
PDF file
NENesrine Ebrahim
Nesrine Ebrahim
IAInas A. Ahmed
Inas A. Ahmed
NNoha Hussien
Noha Hussien
ADArigue Dessouky
Arigue Dessouky
AFAyman Samir Farid
Ayman Samir Farid
DSDina Sabry
Dina Sabry
Background: diabetic nephropathy (DN) is a serious complication of diabetes mellitus and a common cause for end stage renal disease. Autophagy has a defensive role against kidney damage caused by hyperglycemia. The mesenchymal stem cells (MSCs) derived exosomes are currently considered as a new promising therapy in chronic renal injury. However, the renal protective mechanism of exosomes on DN has not been completely understood. We examined the potential role of MSCs derived exosomes in enhancement of autophagy activity and its effect on DN. In our study we used five groups of rats; control, DN, DN treated with exosomes, DN treated with 3-methyladenine (3-MA) and chloroquine (inhibitors of autophagy) and DN treated with 3-methyladenine (3-MA) and chloroquine and exosomes groups. We assessed renal functions, morphology and fibrosis. Moreover, autophagy markers; mTOR, Beclin-1, light chain-3 (LC3-II), and LC3-II/LC3-I ratio were detected. Additionally, electron microscopy was used for detection of autophagosomes. Results: Exosomes markedly improved the renal functions and showed histological restoration of renal tissues with significant increase in LC3 and Beclin-1 besides the significant decrease in mTOR and fibrotic markers expression in renal tissue. All previous effects were partially abolished by the autophagy inhibitor, chloroquine and 3-MA. Conclusions: we conclude that autophagy induction by exosomes could attenuate DN in a rat model of streptozotocin-induced diabetes mellitus.

Verified
Journal Article
Open access
PDF file
WGwalaa el gazzar
walaa el gazzar
RSRania E. Sliem
Rania E. Sliem
HBHeba Elsayed Bayoumi
Heba Elsayed Bayoumi
HNHend Elsayed Nasr
Hend Elsayed Nasr
MSManar Shabanah
Manar Shabanah
AFAmina Farag
Amina Farag
There have been concerns about the potential health risks posed by microplastics (MP). The detection of MP in a variety of food products revealed that humans are ingesting MP. Nevertheless, there is a paucity of data about their impacts, as well as their uptake, on intestinal barrier integrity. This study examined the toxic effects of oral administration of two doses of polyethylene microplastics (PE-MP) (3.75 or 15 mg/kg/day for 5 weeks; mean particle size: 4.0–6.0 µm) on the intestinal barrier integrity in rats. Moreover, the effect of melatonin treatment with MP exposure was also assessed. The PE-MP particle uptake, histopathological changes, Alcian blue staining, Muc2 mRNA, proinflammatory cytokines (IL-1β and TNF-α), and cleaved caspase-3, as well as tight junction proteins (claudin-1, myosin light-chain kinase (MLCK), occludin, and zonula occludens-1 (ZO-1)) were assessed. Oral administration of PE-MP resulted in apparent jejunal histopathological alterations; significantly decreased mucin secretion, occludin, ZO-1, and claudin-1 expression; and significantly upregulated MLCK mRNA, IL-1β concentration, and cleaved caspase-3 expression. Melatonin reversed these altered parameters and improved the PE-MP-induced histopathological and ultrastructure changes. This study highlighted the PE-MP’s toxic effect on intestinal barrier integrity and revealed the protective effect of melatonin.


Verified
Journal Article
Open access
PDF file
KSKarema Mohamed Soliman
Karema Mohamed Soliman
YMYasmin Mahran
Yasmin Mahran
WGwalaa el gazzar
walaa el gazzar
HYHeba Salem Youssef
Heba Salem Youssef
AHAhmed Mohsen Hamdan
Ahmed Mohsen Hamdan
AMAsmaa A. Mohammed
Asmaa A. Mohammed
Alzheimer’s disease (AD) is a significant health challenge in the 21st century. In spite of the approval of many new disease-modifying therapies for AD, the clinical advantages of these new treatments are less certain. Aim: This investigation was intended to determine the potential neuroprotective impact of morin hydrate (MH), zeolite clinoptilolite (ZC), and/or physical and mental activities (PhM) on an aluminum chloride (AlCl3)-induced AD rat model. Methods: Male Sprague Dawley rats were randomly allocated into seven groups. Group I was the control group. Groups II–VII were treated with AlCl3 for 5 weeks. Groups III–VII were tested for the effects of MH, ZC, and/or PhM. Biochemical, brain histopathological, and behavioral studies were performed. Results: PhM, MH, and ZC combined therapy exhibited a significant neuroprotective effect demonstrated by corrected catecholamines and tau and β-amyloid levels, as well as the antioxidant and anti-ferroptotic effects probably through Nrf2/HO-1/GPX4 and ACSL4 signaling pathways. In addition, combined therapy counteracted the inflammatory responses through modulating the TLR4/NF-κβ/NLRP3 inflammasome expression. Moreover, combined therapy groups showed the maximum improvement of both APOE4/LRP1 and Wnt3/β-catenin/GSK-3β signaling expressions. Conclusion: This research highlights the neuroprotective impact of MH and ZC plus PhM against AlCl3-induced AD via modulation of Nrf2/HO-1/GPX4, TLR4/NF-κβ/NLRP3, APOE4/LRP1, and Wnt3/β-catenin/GSK-3β signaling pathways. It is the first to point out the inclusion of ferroptosis-Nrf2/inflammasomes cross-talk in the neuroprotection mechanism of MH/ZC against the AlCl3-mediated AD model.

21 January 2021 in Biomarkers
Verified
Journal Article
Closed access
MEMostafa Elmadawy
Mostafa Elmadawy
OAOmnia A. Abdullah
Omnia A. Abdullah
WGwalaa el gazzar
walaa el gazzar
EAEnas Sebaey Ahmad
Enas Sebaey Ahmad
SASeham Gouda Ameen
Seham Gouda Ameen
AAAfaf Abdelkader
Afaf Abdelkader
Chronological age estimation is a challenging marker in the field of forensic medicine. The current study aimed to investigate the accuracy of signal joint T-cell receptor rearrangement excision ci...