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Glyphosate (GLY) is a widely used herbicide, particularly in agriculture, and its residues in plants and soil can induce toxic effects in various organisms, including humans, with the brain being especially vulnerable. Eugenol (EU), a natural antioxidant found in cloves, has demonstrated protective effects against different toxic substances. This experimental study explored whether eugenol could mitigate neurological damage triggered by glyphosate exposure in rats. A total of forty male Sprague-Dawley rats were allocated into five experimental groups consisting of control, eugenol (100 mg/kg), glyphosate (150 mg/kg), EU50 combined with glyphosate (50 mg/kg + 150 mg/kg), and EU100 combined with glyphosate (100 mg/kg + 150 mg/kg). Animals received the respective treatments by oral gavage for a period of seven days. Motor and anxiety-related behaviors were evaluated using behaviour tests, after which brain tissues were processed for histopathological analysis. Biochemical analyses included ELISA assessment of oxidative stress markers (MDA, SOD1, GSH, and GPx1), RT-PCR analysis of endoplasmic reticulum (ER) stress- and apoptosis-related genes (GRP78, ATF4, CHOP, PI3K/AKT/mTOR, BAX, and Bcl-2), Western blot evaluation of inflammatory and antioxidant signaling pathways (TLR4/NF-κB and Nrf2/HO-1/SIRT1), and immunohistochemical and immunofluorescence analyses of neuroplasticity, circadian rhythm, and autophagy markers (BDNF, BMAL1, CLOCK, Beclin-1, and LC3A/B). GLY exposure significantly increased lipid peroxidation (MDA), ER stress markers (GRP78 and CHOP), pro-inflammatory mediators (TLR4, NF-κB, TNF-α, and IL-1β), apoptotic signaling (BAX and caspase-3), and autophagy-related proteins, while suppressing antioxidant pathway components. Glyphosate exposure induced behavioral impairments accompanied by increased oxidative stress, inflammatory activation, endoplasmic reticulum stress, apoptosis, and dysregulated autophagy in cerebral cortex tissue. EU treatment dose-dependently attenuated these molecular and histopathological alterations, restored antioxidant and cellular stress responses, and significantly improved behavioral performance, indicating a protective role against GLY-induced neurotoxicity. Overall, EU may represent a promising therapeutic candidate for mitigating herbicide-induced brain injury. Show less

Paclitaxel (PTX) is a potent taxane widely used in the treatment of solid tumors and can cause dose-limiting peripheral neuropathy. This study evaluated the therapeutic potential of selenium in a paclitaxel-induced peripheral neuropathy model. A total of 30 male Sprague-Dawley rats were divided into five groups (n=6): Control, SE1, PTX, PTX+SE0.5, and PTX+SE1. PTX (2mg/kg, i.p., days 1-5) was administered followed by SE (0.5 or 1mg/kg, i.g., days 6-15); sciatic nerve tissues were analyzed on day 16. In addition to molecular and histopathological analyses, behavioral assessments were performed to evaluate mechanical nociception, locomotor activity, and anxiety-like behavior. PTX significantly reduced mechanical pain threshold, impaired locomotor performance, and decreased exploratory behavior. At the molecular level, PTX increased oxidative stress by elevating MDA levels while decreasing SOD and GSH; it also increased TNF-α, IL-1β, and IL-6, and reduced IL-10 levels. Histopathologically, marked axonal degeneration and demyelination, along with reduced myelin fiber area, were observed. SE treatment, particularly at 1mg/kg, restored mechanical pain threshold, improved locomotor parameters, and attenuated anxiety-like behavior. SE also brought oxidative stress markers closer to control levels, suppressed pro-inflammatory cytokines, increased IL-10, reduced histopathological damage, and improved myelin integrity. Immunostaining revealed that SE attenuated PTX-induced increases in BAX, caspase-3, and 8-OHdG, while partially reversing the decrease in Bcl-2. In qPCR analyses, PTX decreased BDNF and increased GFAP expression, which were normalized by SE. SE suppressed the PTX-induced increase in Keap-1 and enhanced Nrf-2 expression. In addition, SE treatment partially restored HO-1 expression, with statistically significant increases observed compared to the PTX group, although levels did not fully return to control values. Show less

(ACR)-induced neurotoxicity, focusing on oxidative stress, endoplasmic reticulum (ER) stress, neuroinflammation, and apoptosis mechanisms. Fifty male Sprague-Dawley rats were divided into five groups: Control, ACR, GA50 +ACR, GA100 +ACR, and GA100. GA (50 and µmg/kg) and ACR (50 mg/kg) were administered intraperitoneally for 14 days. ACR exposure significantly decreased antioxidant enzyme activities (SOD, GSH, GPx, CAT) and increased malondialdehyde (MDA) levels, pro-inflammatory cytokines (TNF-α, IL-1β, IL-6), neuronal nitric oxide synthase (nNOS), and apoptosis-related gene expression (Bax and caspase-3). Histopathological analysis revealed neuronal degeneration and vascular hyperemia, while BDNF, Nrf2, and HO-1 immunoreactivity decreased in the ACR group. GA treatment, particularly at 100 mg/kg, markedly ameliorated these biochemical, molecular, and histopathological alterations. These findings indicate that GA exerts significant neuroprotective effects against ACR-induced brain injury by modulating oxidative stress, ER stress, inflammatory, and apoptotic pathways. Show less

Hepatic encephalopathy (HE) is a severe neuropsychiatric complication of liver dysfunction, driven by hyperammonemia, oxidative stress, neuroinflammation, apoptosis, and endoplasmic reticulum (ER) stress, which disrupt the hepato-encephalic axis and impair cognition and motor functions. Despite its clinical burden, effective therapies that target this multi-organ pathology remain limited. β-Caryophyllene (BCP), an antioxidant and anti-inflammatory dietary sesquiterpene, has not been evaluated for its ability to modulate liver-brain crosstalk in HE. This study investigated the hepatoprotective and neuroprotective effects of BCP in a rat model of thioacetamide (TAA)-induced HE. Rats received TAA (200 mg/kg, i.p.) for three days, followed by BCP (100-400 mg/kg) for 14 days. A comprehensive evaluation included serum biochemistry, oxidative stress indices, inflammatory cytokines, apoptosis-related proteins, neurotrophic factors (BDNF), astroglial activation marker (GFAP), ER stress regulators (GRP78, IRE1, XBP1, PERK, CHOP, ATF6), histopathology, and behavioral outcomes. TAA caused severe hepatic and cerebral injury with elevated liver enzymes, oxidative and inflammatory mediators, ER stress dysregulation, pro-apoptotic signaling, reduced BDNF and GFAP, and impaired motor and exploratory behaviors. BCP treatment dose-dependently restored biochemical and molecular parameters, suppressed oxidative stress and neuroinflammation, normalized ER stress signaling, promoted anti-apoptotic pathways, preserved BDNF and maintained astroglial status as reflected by GFAP, and improved histoarchitecture. Importantly, moderate to high doses fully restored locomotor and exploratory activity, indicating coordinated protection across the hepato-encephalic axis. Here, for the first time, the BCP concurrently mitigates hepatic and cerebral pathology via oxidative, inflammatory, apoptotic, and ER stress pathways, supporting its translational potential as a dual hepatoprotective and neuroprotective candidate for xenobiotic-induced HE and related liver-brain disorders. Show less

Ischemic stroke (IS) is a leading cause of death and permanent disability worldwide. Diabetes is a major risk factor for IS and independently increases mortality. This study investigated the neuroprotective effects of Myrtenal (Myrt) in a rat model of IS under both diabetic and non-diabetic conditions. Sprague Dawley rats received Myrt (40 mg/kg, intraperitoneally) for 28 days before undergoing 60-minute middle cerebral artery occlusion followed by 24 h of reperfusion. Neurological outcomes were assessed using behavioral tests, infarct volume was measured by TTC staining, and biochemical analyses evaluated oxidative stress (MDA, SOD, CAT, GSH-Px) and inflammatory markers (NLRP3, TNF-α, IL-6, IL-1β). Western blotting was performed to examine BDNF/TrkB, p-PI3K/p-Akt signaling, and apoptosis-related proteins (Caspase-3, Bcl-2, Bax). IS impaired neurological function and increased infarct size, apoptosis, inflammation, and lipid peroxidation, while reducing antioxidant enzymes and BDNF/TrkB and p-PI3K/p-Akt levels (p < 0.05). These pathological changes were more severe in diabetic rats. Pretreatment with Myrt significantly ameliorated these effects in both diabetic and non-diabetic groups (p < 0.05). These findings suggest that Myrt exerts neuroprotective effects against IS by suppressing inflammation, oxidative stress, and apoptosis, possibly through modulation of BDNF/TrkB and p-PI3K/p-Akt pathways. These findings indicate that Myrt may possess neuroprotective potential in IS under both hyperglycemic and normoglycemic conditions. Show less

Microtubule-actin cross-linking factor 1 (MACF1) is a large protein of the spectraplakin family, which is essential for brain development. MACF1 interacts with microtubules through the growth arrest-specific 2 (Gas2)-related (GAR) domain. Heterozygous MACF1 missense variants affecting the zinc-binding residues in this domain result in a distinctive cortical and brain stem malformation. Evidence for other MACF1-associated disorders is still limited. Here, we present a cohort of 45 individuals with heterozygous or bi-allelic MACF1 variants to explore the phenotypic spectrum and assess possible pathogenic relevance. We observe that de novo heterozygous missense variants in the EF-hand domains also result in distinctive brain malformation and provide experimental evidence that variants in the EF-hand/GAR module increase microtubule binding, suggestive of a toxic gain of function. Notably, no phenotype-genotype correlation was possible for the remaining heterozygous variants in other domains. A clinical review of eight families with bi-allelic variants reveals a possible complex neurodevelopmental syndrome of the central and peripheral nervous systems. In these individuals, bi-allelic variants mostly affect the Plakin domain. Furthermore, RNA sequencing and chromatin immunoprecipitation (ChIP) analyses of human fetal brain tissue reveal five MACF1 isoforms with region-specific expression, differing in their exon 1 transcription start sites but splicing to a common exon 2. This differential expression explains the frontal-predominant lissencephaly in an individual with a homozygous stop-gain in exon 1 (MACF1-204: c.70C>T [p.Arg24∗]), as this isoform is preferentially expressed in the frontal cortex. We conclude that MACF1-related disorders are strictly linked to domain function and the level of transcript expression, explaining the observed wide clinical heterogeneity. Show less

There are few causes of treatable neurodevelopmental diseases described to date. Branched-chain ketoacid dehydrogenase kinase (BCKDK) deficiency causes branched-chain amino acid (BCAA) depletion and is linked to a neurodevelopmental disorder characterized by autism, intellectual disability and microcephaly. We report the largest cohort of patients studied, broadening the phenotypic and genotypic spectrum. Moreover, this is the first study to present newborn screening findings and mid-term clinical outcome. In this cross-sectional study, patients with a diagnosis of BCKDK deficiency were recruited via investigators' practices through a MetabERN initiative. Clinical, biochemical and genetic data were collected. Dried blood spot (DBS) newborn screening (NBS) amino acid profiles were retrieved from collaborating centres and compared to a healthy newborn reference population. Twenty-one patients with BCKDK mutations were included from 13 families. Patients were diagnosed between 8 months and 16 years (mean: 5.8 years, 43% female). At diagnosis, BCAA levels (leucine, valine and isoleucine) were below reference values in plasma and in CSF. All patients had global neurodevelopmental delay; 18/21 had gross motor function (GMF) impairment with GMF III or worse in 5/18, 16/16 intellectual disability, 17/17 language impairment, 12/17 autism spectrum disorder, 9/21 epilepsy, 12/15 clumsiness, 3/21 had sensorineural hearing loss and 4/20 feeding difficulties. No microcephaly was observed at birth, but 17/20 developed microcephaly during follow-up. Regression was reported in six patients. Movement disorder was observed in 3/21 patients: hyperkinetic movements (1), truncal ataxia (1) and dystonia (2). After treatment with a high-protein diet (≥ 2 g/kg/day) and BCAA supplementation (100-250 mg/kg/day), plasma BCAA increased significantly (P < 0.001), motor functions and head circumference stabilized/improved in 13/13 and in 11/15 patients, respectively. Among cases with follow-up data, none of the three patients starting treatment before 2 years of age developed autism at follow-up. The patient with the earliest age of treatment initiation (8 months) showed normal development at 3 years of age. NBS in DBS identified BCAA levels significantly lower than those of the normal population. This work highlights the potential benefits of dietetic treatment, in particular early introduction of BCAA. Therefore, it is of utmost importance to increase awareness about this treatable disease and consider it as a candidate for early detection by NBS programmes. Show less