👤 Nisreen M Khalifa

Neuroinflammation appears in a variety of neurological disorders, including multiple sclerosis (MS), Parkinson's disease (PD), Alzheimer's disease (AD), and amyotrophic lateral sclerosis. The adenosine A₂A receptor (A₂AR), a Gs protein-coupled receptor that affects cAMP signaling and downstream kinases like PKA, CREB, and NF-κB, is one of the primary regulators of this process. Context-dependent effects of A₂AR activation include lowering acute inflammation and promoting neuronal survival when stimulated moderately, but increasing glial activation and cytokine production when overexpressed over an extended period of time. In microglia and astrocytes, A₂AR signaling regulates inflammatory pathways mediated by NF-κB and MAPK, affecting oxidative stress, blood-brain barrier (BBB) stability, and excitotoxicity. Acute or transient (short-term) A₂AR activation, on the other hand, increases the production of anti-inflammatory cytokines like IL-10 and enhances neurotrophic support through BDNF. A₂AR antagonists, including istradefylline and SCH58261, may reduce microglial triggering and have neuroprotective benefits, according to clinical and experimental data. The context-dependent activity of the receptor is shown by the fact that total receptor blockage interferes with adaptive immune control. Therefore, the therapeutic challenge is to carefully modify A₂AR signaling in particular cell populations, specifically targeting astrocytic or microglial receptors while maintaining the peripheral immunoregulatory activities. The dual regulatory role of A₂AR in neuroinflammation is summarized in this review along with its molecular mechanisms, disease-specific actions, and therapeutic significance. Developing next-generation neuroprotective strategies that reduce A₂AR signaling's pro-inflammatory and neurotoxic effects while preserving its beneficial homeostatic effects will require an understanding of the temporal and cell-specific dynamics of this signaling. Show less

This study aimed to investigate how nano curcumin (Nano-Cur) or nano-chromium chloride (Nano-CrCl) in comparison with metformin (Met), can reduce diabetic neuropathy caused by streptozotocin (STZ) in rats. Seventy Wistar albino male rats were randomly divided into seven groups (ten rats/group): control; STZ-induced diabetes; diabetic rats receiving daily oral doses of Nano-Cur, Cur, Nano-CrCl, CrCl, and Met. The present results show that all treated groups significantly alleviated diabetic neuropathy by restoring serum insulin and glucose levels, enhancing cerebral antioxidant activities and activating IR/PI3K/AKT, normalizing neurotransmitters, decreasing oxidative stress markers (MDA), and reducing inflammatory biomarkers and pyroptotic biomarkers. At the molecular level, the levels of GSK3B, JAK-2, STAT-3, AMPK, and BACE1 were significantly downregulated in all treated diabetic groups compared to the diabetic group, especially Nano-Cur and Met. However, Cur, Nano-CrCl, and CrCl did not cause any significant (p > 0.05) alteration in ACh levels compared to the diabetic group. Additionally, the Nano-Cur, Cur, and Met groups exhibited a marked increase in miRNA-223-3p and miRNA-124 levels, whereas Nano-CrCl and CrCl showed no significant changes in these miRNAs when compared to the diabetic group. Show less

This study investigated the neuroprotective effect of ferulic acid (FA) against bisphenol A (BPA) induced Alzheimer's disease-like pathology in male rats. Rats were allocated into four groups, control, BPA, BPA + FA, and FA, respectively, for 40 days. Spatial working memory and recognition memory were evaluated. Moreover, the brain levels of oxidative stress biomarkers, proinflammatory cytokines, extracellular signal-regulated kinase (ERK), and phosphorylated serine/threonine protein kinase (p-Akt) were measured. We also determined the brain neuropathological protein levels, including Beta-Amyloid 1-42, total Tau (tTau), and phosphorylated Tau (pTau) proteins. Furthermore, brain levels of Acetylcholinesterase (AChE) and Beta-secretase (BACE) were assessed. Brain histological investigation and immunohistochemistry determination of glial fibrillar acidic protein (GFAP) were also performed. Moreover, docking simulation was adapted to understand the inhibitory role of FA on AChE, BACE-1, and ERK1/2. Interestingly, the BPA + FA treated group showed a reversal in the cognitive impairments induced by BPA, which was associated with improved brain redox status. They also exhibited a significant decrease in brain inflammatory cytokines, ERK, and p-Akt levels. Moreover, they revealed a decline in beta-amyloid 1-42 and a significant improvement in tTau expression and pTau protein levels in the brain tissue. Further, the brain levels of AChE and BACE were substantially reduced in BPA + FA rats. The neuroprotective effect of FA was confirmed by restoring the normal architecture of brain tissue, which was associated with decreasing GFAP. FA could be a potent neuroprotectant agent against AD with a possible prospect for its therapeutic capabilities and nutritional supplement value due to its antioxidant and antiapoptotic properties. Show less

The molecular pathogenesis of hepatocellular carcinoma (HCC) exhibits striking etiological heterogeneity, with non-HCV-associated cases representing an increasingly prominent clinical challenge in regions like Egypt, where environmental carcinogens significantly contribute to the disease burden. Through integrated analysis of genomic data Egyptian cohort comprising 48 HCC cases (23 non-HCV, 25 HCV-positive) was examined and validated against TCGA/ICGC datasets using cBioPortal and Cytoscape. This study identifies a distinct oncogenic program in non-viral HCC characterized by recurrent alterations in receptor tyrosine kinases (RTKs) FGFR1, MET, ERBB2 and FLT3. These mutations were found to be 4.3-fold more prevalent in non-HCV HCC compared to viral counterparts (26.1% vs. 6.0%, p=0.008), demonstrating strong etiological specificity. Functional characterization revealed these alterations converge on MAPK and PI3K-AKT-mTOR signaling cascades through shared adaptor proteins, creating an interconnected signaling network that drives tumor progression. Clinically, FGFR1/MET co-alterations predicted significantly worse outcomes (HR=2.3 for recurrence, 95% CI 1.1-4.8), while maintaining 92% specificity for non-viral HCC diagnosis. These findings establish the FGFR1-MET-ERBB2 axis as both a molecular classifier and therapeutic target, providing a rationale for etiology-specific management strategies in HCC precision oncology. Show less

Malignant liver disease is among the highest in the world, with hepatocellular carcinoma (HCC) accounting for up to 90 % of all cases. In Egypt, HCC poses a significant public-health concern, representing 47.17 % of cancer cases. The high incidence of hepatitis C virus (HCV) in the Egypt was a major predisposing factor for HCC. This study included 63 Egyptian HCC patients, 55 % of whom had a history of HCV infection. Using a paired sampling strategy, approximately 2800 COSMIC mutations from 50 oncogenes and tumor-suppressor genes were NGS sequenced. Total of 381 somatic mutations were identified, 91 mutations detected in the HCC group and 291 in the HCV-related HCC group. The top 10 mutated genes in the non-HCV group were TP53, ATM, EGFR, CDH1, FGFR1, MET, SMAD4, ERBB2, FLT3, and FBXW7, while in the HCV-related HCC group, genes were KIT, ATM, TP53, APC, FBXW7, KDR, RB1, SMAD4, EGFR, and PIK3CA. The present study represents the first comprehensive somatic mutation profile in HCC Egyptian patients. This finding suggests that HCV viral infection played a direct and indirect role in increasing the somatic mutation burden in HCV-related HCC patients and opens new promises of targeted therapies for those patients. Show less

Mitogen-activated protein kinase (MAPK) pathway alteration is a major oncogenic driver in paediatric low-grade gliomas (LGG) and some adult gliomas, encompassing BRAF (most common) and non-BRAF alterations. The aim was to determine the frequency, molecular spectrum and clinicopathological features of MAPK-altered gliomas in paediatric and adult patients at our neuropathology site in Kuwait. We retrospectively searched the data of molecularly sequenced gliomas between 2018 and 2023 for MAPK alterations, revised the pathology in view of the 2021 WHO classification and evaluated the clinicopathological data for possible correlations. Of 272 gliomas, 40 (15%) harboured a MAPK pathway alteration in 19 paediatric (median 9.6 years; 1.2-17.6) and 21 adult patients (median 37 years; 18.9-89.2), comprising 42% and 9% of paediatric and adult cases, respectively. Pilocytic astrocytoma and glioblastoma were the most frequent diagnoses in children (47%) and adults (43%), respectively. BRAF V600E (n=17, 43%) showed a wide distribution across age groups, locations and pathological diagnoses while KIAA1549::BRAF fusion (n=8, 20%) was spatially and histologically restricted to cerebellar paediatric LGGs. Non-V600E variants and BRAF amplifications accompanied other molecular aberrations in high-grade tumours. Non-BRAF MAPK alterations (n=8) included mutations and gene fusions involving FGFR1, NTRK2, NF1, ROS1 and MYB. Fusions included KANK1::NTRK2, GOPC::ROS1 (both infant hemispheric gliomas), FGFR1::TACC1 (diffuse LGG), MYB::QKI (angiocentric glioma) and BCR::NTRK2 (glioblastoma). Paradoxical H3 K27M/MAPK co-mutations were observed in two LGGs. The study provided insights into MAPK-altered gliomas in Kuwait highlighting the differences among paediatric and adult patients and providing a framework for planning therapeutic polices. Show less

Monogenic obesity is a rare form of obesity due to pathogenic variants in genes implicated in the leptin-melanocortin signaling pathway and accounts for around 5% of severe early-onset obesity. Mutations in the genes encoding the MC4R, leptin, and leptin receptor are commonly reported in various populations to cause monogenic obesity. Determining the genetic cause has important clinical benefits as novel therapeutic interventions are now available for some forms of monogenic obesity. To unravel the genetic causes of early-onset obesity in the population of Qatar. In total, 243 patients with early-onset obesity (above the 95% percentile) and age of onset below 10 years were screened for monogenic obesity variants using a targeted gene panel, consisting of 52 obesity-related genes. Thirty rare variants potentially associated with obesity were identified in 36 of 243 (14.8%) probands in 15 candidate genes (LEP, LEPR, POMC, MC3R, MC4R, MRAP2, SH2B1, BDNF, NTRK2, DYRK1B, SIM1, GNAS, ADCY3, RAI1, and BBS2). Twenty-three of the variants identified were novel to this study and the rest, 7 variants, were previously reported in literature. Variants in MC4R were the most common cause of obesity in our cohort (19%) and the c.485C>T p.T162I variant was the most frequent MC4R variant seen in 5 patients. We identified likely pathogenic/pathogenic variants that seem to explain the phenotype of around 14.8% of our cases. Variants in the MC4R gene are the commonest cause of early-onset obesity in our population. Our study represents the largest monogenic obesity cohort in the Middle East and revealed novel obesity variants in this understudied population. Functional studies will be required to elucidate the molecular mechanism of their pathogenicity. Show less

PurposeThe application of genomic sequencing to investigate unexplained death during early human development, a form of lethality likely enriched for severe Mendelian disorders, has been limited.MethodsIn this study, we employed exome sequencing as a molecular autopsy tool in a cohort of 44 families with at least one death or lethal fetal malformation at any stage of in utero development. Where no DNA was available from the fetus, we performed molecular autopsy by proxy, i.e., through parental testing.ResultsPathogenic or likely pathogenic variants were identified in 22 families (50%), and variants of unknown significance were identified in further 15 families (34%). These variants were in genes known to cause embryonic or perinatal lethality (ALPL, GUSB, SLC17A5, MRPS16, THSD1, PIEZO1, and CTSA), genes known to cause Mendelian phenotypes that do not typically include embryonic lethality (INVS, FKTN, MYBPC3, COL11A2, KRIT1, ASCC1, NEB, LZTR1, TTC21B, AGT, KLHL41, GFPT1, and WDR81) and genes with no established links to human disease that we propose as novel candidates supported by embryonic lethality of their orthologs or other lines of evidence (MS4A7, SERPINA11, FCRL4, MYBPHL, PRPF19, VPS13D, KIAA1109, MOCS3, SVOPL, FEN1, HSPB11, KIF19, and EXOC3L2).ConclusionOur results suggest that molecular autopsy in pregnancy losses is a practical and high-yield alternative to traditional autopsy, and an opportunity for bringing precision medicine to the clinical practice of perinatology. Show less

Dyggve-Melchior-Clausen (DMC) syndrome is a rare autosomal recessive disorder characterized by the association of a progressive spondyloepimetaphyseal dysplasia and mental retardation ranging from mild to severe. The disorder results from mutations in the dymeclin (DYM) gene in the 18q12-12.1 chromosomal region. We report two siblings with classical clinical and radiological features of DMC and asymptomatic atlanto-axial dislocation. A novel homozygous splice-site mutation (IVS15+3G>T) was detected. Reverse transcriptase polymerase chain reaction (RT-PCR) confirmed that this mutation affects normal splicing. To the best of our knowledge, this is the first report of DMC from Saudi Arabia. The splice mutation noted in our patients was compared to the previously reported cases and supports the hypothesis that loss of DYM function is the likely mechanism of disease pathogenesis. In conclusion, distinction between this type of skeletal dysplasia and Morquio disease (MPS IV) is important for paediatricians and clinical geneticist in providing standard patient care and genetic counselling. Show less