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This study aimed to explore the effect and mechanism of polyphyllin Ⅱ in improving di(2-ethylhexyl)phthalate(DEHP)-induced learning and memory impairment. In the experiment, male C57BL/6 mice were randomly divided into five groups: a control group, a model group(exposed to 5 mg·kg~(-1) DEHP), and polyphyllin Ⅱ groups(5 mg·kg~(-1) DEHP + 0.5 mg·kg~(-1) polyphyllin Ⅱ, DEHP + 1 mg·kg~(-1) polyphyllin Ⅱ, and DEHP + 2 mg·kg~(-1) polyphyllin Ⅱ). The learning and memory function of mice was tested using the Morris water maze. The hippocampal neuron structure was detected by Nissl staining. The expression of casein kinase Ⅱ subunit beta(CK2b), protein kinase B(Akt)-cAMP response element binding protein(CREB) pathway-related proteins, as well as postsynaptic density protein 95(PSD95) and synapsin 1 was determined by immunofluorescence and Western blot. The brain-derived neurotrophic factor(BDNF) expression was measured by enzyme-linked immunosorbent assay(ELISA). The results showed that compared with the control group, DEHP induced learning and memory impairment, as well as hippocampal neuronal apoptosis in mice. Additionally, DEHP downregulated CK2b, inhibited the Akt-CREB pathway, and downregulated the PSD95, synapsin1, and BDNF expression. After polyphyllin Ⅱ administration, DEHP-induced learning and memory impairment was significantly improved, with inhibited hippocampal neuronal apoptosis, restored CK2b expression, reactivated Akt-CREB pathway, as well as restored expression of PSD95, synapsin1, and BDNF. Furthermore, the surface plasmon resonance(SPR) experiment of N2a cells demonstrated that polyphyllin Ⅱ targeted CK2b and stabilized its expression. After using siRNA to inhibit CK2b, the neuroprotective effect of polyphyllin Ⅱ was also significantly inhibited, and neuronal apoptosis was reinduced. In conclusion, polyphyllin Ⅱ can ameliorate DEHP-induced learning and memory impairment, with its potential mechanism involving the Akt-CREB pathway activation via CK2b upregulation, which leads to restored PSD95 and synapsin1 expression, and synaptic plasticity, as well as inhibited neuronal apoptosis, ultimately exerting a neuroprotective effect. This study suggests that polyphyllin Ⅱ possesses a neuroprotective effect and has potential application value in improving cognitive impairment. Show less

The accumulation and deposition of amyloid-beta (Aß) peptides is detrimental to neuronal networks and is driven by the cleavage of amyloid precursor protein (APP) by beta-secretase 1 (BACE1). The proteolytic processing of APP is tightly regulated by the opposing activities of BACE1 and ADAM10, with the latter producing a truncated, non-amyloidogenic fragment. Maintaining this balance is critical for normal physiological function, as complete inhibition of BACE1 has proven detrimental owing to the important physiological roles of its many substrates. Brain-derived neurotrophic factor (BDNF), an important mediator of neuronal function and survival, has recently been shown to reduce BACE1 activity in neural tissue, but the mechanism for this remains unknown. Previous research suggests that BACE1 cleavage of APP is favoured at acidic intracellular compartments, whereas non-amyloidogenic processing preferentially occurs at the plasma membrane. Hence, we hypothesized that BDNF alters the subcellular distribution of BACE1, reducing ß-cleavage of APP. Here, we show that acute BDNF treatment of differentiated neural cells (SH-SY5Y) reduced levels of sAPPß, a product of BACE1 cleavage of APP. Using confocal microscopy and quantitative image analysis, we found that this reduction in sAPPß levels is coincident with increased BACE1 localization to the plasma membrane, and a concomitant reduction of BACE1 localization to early endosomes. This effect appears to be independent of clathrin-mediated endocytosis (CME), as inhibition of CME by PitStop2 treatment increased a-cleavage of APP but did not reduce ß-cleavage independent of BDNF treatment. Hence, BDNF may reduce production of Aß by altering BACE1 distribution and decreasing upstream ß-cleavage. Show less

This study aimed to investigate the effects of L-borneol on the molecular, biochemical, and histological damage caused by acrylamide (ACR) in the hippocampus of adult male Wistar rats. It also examined the impact of L-borneol on spatial memory and anxiety-like behaviors in these animals. Animals were divided into four groups: control, L-borneol, ACR, and ACR + L-borneol. ACR (25 mg/kg) and L-borneol (50 mg/kg) were administered orally for 21 consecutive days. L-borneol reduced levels of malondialdehyde and nitric oxide, increased glutathione content, and enhanced superoxide dismutase activity in the hippocampus of rats treated with ACR. In addition, L-borneol lowered the expression of pro-inflammatory markers, nuclear factor-κB, and inducible nitric oxide synthase in the hippocampus. It effectively prevented changes in the expression of apoptosis-related genes, which are associated with decreased neuronal death in the cornus ammonis 1 and dentate gyrus regions. Moreover, L-borneol increased the expression of sirtuin 1 (SIRT1), nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), brain-derived neurotrophic factor, and alpha 7-nicotinic acetylcholine receptors, while reducing the expression and activity of acetylcholinesterase. Finally, L-borneol improved spatial memory and reduced anxiety-like behaviors. In conclusion, L-borneol enhances behavioral performance in ACR-exposed animals by decreasing oxidative and nitrosative stress, as well as inhibiting inflammation and apoptosis. It appears that the upregulation of the SIRT1/Nrf2/HO-1 signaling pathway and the stimulation of acetylcholine signaling are crucial for mitigating ACR-induced neurotoxicity. Show less

Brain-derived neurotrophic factor (BDNF) is a neurotrophin with crucial roles in the developing and adult nervous system, contributing to neuronal survival, differentiation, and synaptic plasticity. The pleiotropic functions of BDNF require stringent spatiotemporal control of its expression, making BDNF one of the most thoroughly studied activity-regulated genes. Over the years, substantial evidence has accumulated, providing insights into BDNF gene structure, numerous mRNA variants, their different localization patterns and translational efficiencies, as well as the functions of the BDNF protein in different tissues. This review aims to summarize the current understanding of the mechanisms governing BDNF expression at transcriptional, posttranscriptional, and translational levels, offering an integrated perspective of BDNF regulation. Show less

The pituitary gland plays a pivotal role in regulating puberty and reproductive physiology; however, the precise cellular and molecular mechanisms driving the pubertal transition in large animal, such as ewes, remain poorly understood. Here, we generated a comprehensive single-cell transcriptomic atlas of the ovine anterior pituitary, specifically comparing the pre-pubertal (3 month) and post-pubertal (6 month) stages. We identified 30 335 cells classified into ten distinct clusters. Comparative analysis revealed a global transcriptional reprogramming during puberty, characterized by a marked upregulation of genes associated with ribosome biogenesis, unfolded protein response, and hormone secretion across endocrine cells, reflecting an expanded biosynthetic capacity. Specifically, we identified SCG2 as a critical regulator of gonadotroph maturation. Functional validation demonstrated that SCG2 facilitates the biogenesis of secretory granules, thereby promoting FSH synthesis and secretion. Furthermore, intercellular communication analysis uncovered a distinct shift in the pituitary microenvironment: the 6 month pituitary exhibited enhanced regulatory networks, including IGF signaling mediated by non-endocrine cells and NT signaling (e.g., BDNF-NTRK2) driven by multiple cell types. These findings suggest that the onset of puberty relies on a coordinated "endocrine-to-endocrine" and "non-endocrine-to-endocrine" crosstalk. This study provides a high-resolution molecular blueprint of the pubertal transition, highlighting the key roles of biosynthetic machinery upgrades and microenvironmental remodeling in establishing the high reproductive performance of Hu sheep. Show less

Lilium brownii is a plant that can be used for medicinal and food purposes. 1-O-p-coumaroyl-3-O-feruloyl glycerol (CF) is a phenolic acid glycerol dimer isolated from Lilium brownii. This study aims to evaluate the neuroprotective effects of CF and elucidate the possible molecular mechanisms underlying its neuroprotective effects through in vivo and in vitro models of Parkinson's disease. 1-methyl-4-phenylpyridinium ions (MPP Following CF administration, the apoptosis rate and reactive oxygen species (ROS) levels in PC12 cells were significantly reduced. CF markedly upregulated the expression of proteins including dopamine, tyrosine hydroxylase, brain-derived neurotrophic factor (BDNF), while simultaneously downregulating the expression of proteins such as α-synuclein. Molecular docking results demonstrated favorable affinity between CF and proteins including p62. This compound not only ameliorated motor and cognitive impairments in Parkinson's disease mice but also markedly increased neuronal numbers within the substantia nigra region of these animals. CF exerts a neuroprotective effect in Parkinson's disease by modulating the p62-Keap1-Nrf2 signalling pathway. Show less