👤 Lama Nasser

Tropomyosin receptor kinase B (TrkB) is a critical mediator of neuronal growth, survival, and synaptic plasticity, which is activated by the endogenous ligand, brain-derived neurotrophic factor (BDNF). TrkB has been implicated in a wide range of neurological conditions, including neurodegenerative, psychiatric, and proliferative disorders. Non-invasive imaging of TrkB using positron emission tomography (PET) has been pursued to enhance understanding of its role in disease and support therapeutic development. Here, we investigated the in vitro and in vivo properties of [ Show less

Current antiepileptic drugs are effective in suppressing motor seizures; however, they often do not address the underlying factors such as oxidative stress, inflammation, and neurotrophic imbalances that contribute to the development of epilepsy. Recently, flavonoids sourced from diet have attracted attention as neuromodulators that can target these root causes. This study evaluated the protective effects of sakuranetin-a flavonoid found in edible Prunus species-against pentylenetetrazole (PTZ)-induced seizures and neurochemical changes in mice. Swiss albino mice (n = 6/group) were treated with saline, PTZ (35 mg/kg, intraperitoneally), or PTZ combined with sakuranetin (10 or 20 mg/kg, orally) every other day for 28 days. The study assessed seizure activity, oxidative stress markers, inflammatory cytokines, brain-derived neurotrophic factor (BDNF), tropomyosin receptor kinase B (TrkB), and caspase-3 activity. Additionally, in silico docking and 100 ns molecular dynamics simulations were performed to investigate sakuranetin's interactions with BDNF, TrkB, and D₂-like receptors. The results showed that sakuranetin treatment significantly improved seizure parameters. The onset latency was extended with both doses. The duration of clonic-tonic seizures was reduced by half, and mortality rates dropped from 50% to 8%. PTZ-induced reductions in neurotransmitters (such as GABA, dopamine, norepinephrine, serotonin, and acetylcholine) were restored, antioxidant defenses (including superoxide dismutase, catalase, and glutathione) were enhanced, and both lipid peroxidation (measured by malondialdehyde) and nitrosative stress (nitric oxide) were significantly decreased. Pro-inflammatory cytokines (IL-1β, IL-6, TNF-α) were reduced, BDNF and TrkB levels approached control levels, and caspase-3 activity was diminished. Docking studies and MM-GBSA analyses indicated that BDNF was the most favorable binding partner for sakuranetin (with a binding free energy of approximately - 57 kcal/mol), and the simulations affirmed the stability of the complex. These findings suggest that sakuranetin has substantial, multi-target anticonvulsant effects by restoring neurotransmitter balance, enhancing antioxidant capacity, suppressing neuroinflammation, and revitalizing BDNF/TrkB signaling. Given its dietary origin, sakuranetin warrants further investigation as a potential nutraceutical candidate for managing epilepsy. Show less

Low serum levels of high-density lipoprotein cholesterol (HDL-C) have been shown to be a risk factor for coronary artery disease independent of low-density lipoprotein cholesterol (LDL-C) in different populations. In this study, we investigated genetic variants through genome-wide association studies to determine their association with HDL-C levels in a sample of 2,700 patients. We identified several SNPs associated with HDL-C levels in the Lebanese population using unadjusted and adjusted by biological factors models. We replicated the association of rs3764261 within CETP with HDL-C levels in the study population, and found other previously unidentified SNPs to be significant at the suggestive level, in both previously identified and unidentified genes. This paper reports the first genome-wide analysis of HDL-C in the Lebanese, Middle Eastern, population and supports the importance of genome-wide association studies across different and minor ethnicities to understand better the etiology of complex human diseases. Show less

The objective of this study was to evaluate the biological activities of the major phytosterols present in argan oil (AO) and in cactus seed oil (CSO) in BV2 microglial cells. Accordingly, we first determined the sterol composition of AO and CSO, showing the presence of Schottenol and Spinasterol as major sterols in AO. While in CSO, in addition to these two sterols, we found mainly another sterol, the Sitosterol. The chemical synthesis of Schottenol and Spinasterol was performed. Our results showed that these two phytosterols, as well as sterol extracts from AO or CSO, are not toxic to microglial BV2 cells. However, treatments by these phytosterols impact the mitochondrial membrane potential. Furthermore, both Schottenol and Spinasterol can modulate the gene expression of two nuclear receptors, liver X receptor (LXR)-α and LXRβ, their target genes ABCA1 and ABCG1. Nonetheless, only Schottenol exhibited a differential activation vis-à-vis the nuclear receptor LXRβ. Thus Schottenol and Spinasterol can be considered as new LXR agonists, which may play protective roles by the modulation of cholesterol metabolism. Show less