Additive Effect of Resveratrol on Astrocyte Swelling Post-exposure to Ammonia, Ischemia and Trauma In Vitro

The Importance of Mitochondrial Processes in the Maturation and Acquisition of Competences of Oocytes and Embryo Culture

Mitochondria, as multifunctional and partially independent structures, play a crucial role in determining essential life processes. Recently, their significance in reproductive biology has gained increasing attention. This review aims to comprehensively analyse the role of mitochondrial processes in oocyte maturation and embryo culture. A comprehensive literature review was conducted to highlight the importance of mitochondrial activity in the early stages of life formation. Proper mitochondrial function provides energy, maintains genomic stability, and ensures optimal conditions for fertilisation and embryo progression. Understanding these processes is essential to optimise culture conditions and identify new mitochondrial biomarkers that improve reproductive success and improve assisted reproductive technologies (ARTs). Enhancing mitochondrial function in female reproductive cells is the key to improving oocyte and embryo quality, which can lead to better in vitro fertilisation and embryo transfer. Furthermore, advances in diagnostic techniques, such as mitochondrial genome sequencing, offer a more precise understanding of the relationship between mitochondrial health and oocyte quality. However, fully understanding mitochondrial functions is only part of the challenge. Expanding knowledge of the interactions between mitochondria and other cellular structures is crucial for future advancements in reproductive medicine. Understanding these complex relationships will provide deeper insight into improving reproductive outcomes and embryo development.

Protective Effects of Plant-Derived Compounds Against Traumatic Brain Injury

Inflammation in the nervous system is one of the key features of many neurodegenerative diseases. It is increasingly being identified as a critical pathophysiological primitive mechanism associated with chronic neurodegenerative diseases following traumatic brain injury (TBI). Phytochemicals have a wide range of clinical properties due to their antioxidant and anti-inflammatory effects. Currently, there are few drugs available for the treatment of neurodegenerative diseases other than symptomatic relief. Numerous studies have shown that plant-derived compounds, in particular polyphenols, protect against various neurodegenerative diseases and are safe for consumption. Polyphenols exert protective effects on TBI via restoration of nuclear factor kappa B (NF-κB), toll-like receptor-4 (TLR4), and Nod-like receptor family proteins (NLRPs) pathways. In addition, these phytochemicals and their derivatives upregulate the phosphatidylinositol-3-Kinase/Protein Kinase B (PI3K/AKT) and nuclear factor erythroid 2-related factor 2 (Nrf2) pathways, which have critical functions in modulating TBI symptoms. There is supporting evidence that medicinal plants and phytochemicals are protective in different TBI models, though future clinical trials are needed to clarify the precise mechanisms and functions of different polyphenolic compounds in TBI.

Astrocytes in ischemic stroke: Crosstalk in central nervous system and therapeutic potential

In the central nervous system (CNS), a large group of glial cells called astrocytes play important roles in both physiological and disease conditions. Astrocytes participate in the formation of neurovascular units and interact closely with other cells of the CNS, such as microglia and neurons. Stroke is a global disease with high mortality and disability rate, most of which are ischemic stroke. Significant strides in understanding astrocytes have been made over the past few decades. Astrocytes respond strongly to ischemic stroke through a process known as activation or reactivity. Given the important role played by reactive astrocytes (RAs) in different spatial and temporal aspects of ischemic stroke, there is a growing interest in the potential therapeutic role of astrocytes. Currently, interventions targeting astrocytes, such as mediating astrocyte polarization, reducing edema, regulating glial scar formation, and reprogramming astrocytes, have been proven in modulating the progression of ischemic stroke. The aforementioned potential interventions on astrocytes and the crosstalk between astrocytes and other cells of the CNS will be summarized in this review.

Therapeutic targeting of Ras/Raf/MAPK pathway by natural products: A systematic and mechanistic approach for neurodegeneration

BACKGROUND

Multiple dysregulated pathways are behind the pathogenesis of neurodegenerative diseases (NDDs); however, the crucial targets are still unknown. Oxidative stress, apoptosis, autophagy, and inflammation are the most dominant pathways that strongly influence neurodegeneration. In this way, targeting the Ras/Raf/mitogen-activated protein kinases (MAPKs) pathway appears to be a developing strategy for combating NDDs like Parkinson's disease, Alzheimer's disease, stroke, aging, and other NDDs. Accordingly, plant secondary metabolites have shown promising potentials for the simultaneous modulation of the Ras/Raf/MAPKs pathway and play an essential role in NDDs. MAPKs include p38 MAPK, extracellular signal-regulated kinase 1/2 (ERK 1/2), and c-Jun N-terminal kinase (JNK), which are important molecular players in neurodegeneration. Ras/Raf, which is located the upstream of MAPK pathway influences the initiation and progression of neurodegeneration and is regulated by natural products.

PURPOSE

Thus, the present study aimed to investigate the neuroprotective roles of plant- and marine-derived secondary metabolites against several NDDs through the modulation of the Ras/Raf/MAPK signaling pathway.

STUDY DESIGN AND METHODS

A systematic and comprehensive review was performed to highlight the modulatory roles of natural products on the Ras/Raf/MAPK signaling pathway in NDDs, according to the PRISMA guideline, using scholarly electronic databases, including PubMed, Scopus, and Web of Sciences. Associated reference lists were also searched for the literature review.

RESULTS

From a total of 1495 results, finally 107 articles were included in the present study. The results show that several natural compounds such as alkaloid, phenolic, terpenoids, and nanoformulation were shown to have modulatory effects on the Ras/Raf/MAPKs pathway.

CONCLUSION

Natural products are promising multi-targeted agents with on NDDs through Ras/Raf/MAPKs pathway. Nevertheless, additional and complementary studies are necessary to check its efficacy and potential side effects.

Review of Alzheimer's disease drugs and their relationship with neuron-glia interaction

Alzheimer's disease (AD) is the most common cause of dementia worldwide. Because Alzheimer's disease has no known treatment, sufferers and their caregivers must concentrate on symptom management. Astrocytes and microglia are now known to play distinct physiological roles in synaptic function, the blood-brain barrier, and neurovascular coupling. Consequently, the search for drugs that can slow the degenerative process in dementia sufferers continues because existing drugs are designed to alleviate the symptoms of Alzheimer's disease. Drugs that address pathological changes without interfering with the normal function of glia, such as eliminating amyloid-beta deposits, are prospective treatments for neuroinflammatory illnesses. Because neuron-astrocytes-microglia interactions are so complex, developing effective, preventive, and therapeutic medications for AD will necessitate novel methodologies and strategic targets. This review focused on existing medications used in treating AD amongst which include Donepezil, Choline Alphoscerate, Galantamine, Dextromethorphan, palmitoylethanolamide, citalopram, resveratrol, and solanezumab. This review summarizes the effects of these drugs on neurons, astrocytes, and microglia interactions based on their pharmacokinetic properties, mechanism of action, dosing, and clinical presentations.

Active Ingredients from Euodia ruticarpa Steam Distilled Essential Oil Inhibit PC-3 Prostate Cancer Cell Growth via Direct Action and Indirect Immune Cells Conditioned Media In Vitro

Active constituents isolated from Euodia ruticarpa (ER) steam distilled essential oil (SDEO) against PC-3 prostate cancer cell growth remain unclear. To clarify the puzzle, ER SDEO was extracted and further resolved into six isolated fractions ERF1-F6 with Sephadex LH-20 gel filtration chromatography to analyze their biological activities. Active ingredients in the isolated fractions were analyzed with GC-MS. Potential isolated fractions were selected to treat PC-3 cells with direct action and indirect treatment by mouse splenocyte- (SCM) and macrophage-conditioned media (MCM). The relationship between PC-3 cell viabilities and corresponding total polyphenols, flavonoid contents as well as Th1/Th2 cytokine profiles in SCM was analyzed using the Pearson product-moment correlation coefficient (r). As a result, ERF1-F3 was abundant in total polyphenols and flavonoids contents with diverse active ingredients. Treatments with ERF1-F3 at appropriate concentrations more or less inhibit PC-3 cell growth in a direct action manner. Only SCM, respectively, cultured with ER SDEO and ERF1-F3 markedly enhanced the effects to inhibit PC-3 cell growth, suggesting that secretions by splenocytes might involve anti-PC-3 effects. There are significantly negative correlations between PC-3 cell viabilities and IL-2, IL-10 as well as IL-10/IL-2 ratios in the corresponding SCM. Total polyphenol and flavonoid contents in the media cultured with ER SDEO isolated fractions positively correlated with IL-10 (Th2) and IL-10/IL-2 (Th2/Th1) cytokine secretion ratios by splenocytes, indicating that polyphenol and flavonoid components in ER SDEO isolated fractions promote Th2-polarized and anti-inflammatory characteristics. These new findings concluded that the inhibitory effects against PC-3 prostate cancer cell growth are attributed to active anti-inflammatory ingredients in ER SDEO and its active ERF1-F3 fractions through direct action and indirect treatment by modulating splenocytes' cytokine secretion profiles.

Therapeutic Applications of Resveratrol in Hepatic Encephalopathy through Its Regulation of the Microbiota, Brain Edema, and Inflammation

Hepatic encephalopathy is a common complication in patients with liver cirrhosis and portosystemic shunting. Patients with hepatic encephalopathy present a variety of clinical features, including neuropsychiatric manifestations, cognitive dysfunction, impaired gut barrier function, hyperammonemia, and chronic neuroinflammation. These pathogeneses have been linked to various factors, including ammonia-induced oxidative stress, neuronal cell death, alterations in the gut microbiome, astrocyte swelling, and blood-brain barrier disruptions. Many researchers have focused on identifying novel therapeutics and prebiotics in the hope of improving the treatment of these conditions. Resveratrol is a natural polyphenic compound and is known to exert several pharmacological effects, including antioxidant, anti-inflammatory, and neuroprotective activities. Recent studies suggest that resveratrol contributes to improving the neuropathogenic effects of liver failure. Here, we review the current evidence describing resveratrol's effects in neuropathogenesis and its impact on the gut-liver axis relating to hepatic encephalopathy. We highlight the hypothesis that resveratrol exerts diverse effects in hepatic encephalopathy and suggest that these effects are likely mediated by changes to the gut microbiota, brain edema, and neuroinflammation.

Inhibition of the p‑SPAK/p‑NKCC1 signaling pathway protects the blood‑brain barrier and reduces neuronal apoptosis in a rat model of surgical brain injury

Surgical brain injury (SBI) can disrupt the function of the blood‑brain barrier (BBB), leading to brain edema and neurological dysfunction. Thus, protecting the BBB and mitigating cerebral edema are key factors in improving the neurological function and prognosis of patients with SBI. The inhibition of WNK lysine deficient protein kinase/STE20/SPS1‑related proline/alanine‑rich kinase (SPAK) signaling ameliorates cerebral edema, and this signaling pathway regulates the phosphorylation of the downstream Na⁺‑K⁺‑Cl^‑ cotransporter 1 (NKCC1). Therefore, the purpose of the present study was to investigate the role of SPAK in SBI‑induced cerebral edema and to determine whether the SPAK/NKCC1 signaling pathway was involved in SBI via regulating phosphorylation. An SBI model was established in male Sprague‑Dawley rats, and the effects of SPAK on the regulation of the NKCC1 signaling pathway on BBB permeability and nerve cell apoptosis by western blotting analysis, immunofluorescence staining, TUNEL staining, Fluoro‑Jade C staining, and brain edema and nervous system scores. The results demonstrated that, compared with those in the sham group, phosphorylated (p)‑SPAK and p‑NKCC1 protein expression levels were significantly increased in the SBI model group. After inhibiting p‑SPAK, the expression level of p‑NKCC1, neuronal apoptosis and BBB permeability were significantly reduced in SBI model rats. Taken together, these findings suggested that SBI‑induced increases in p‑SPAK and p‑NKCC1 expression exacerbated post‑traumatic neural and BBB damage, which may be mediated via the ion‑transport‑induced regulation of cell edema.

β-HB inhibits the apoptosis of high glucose-treated astrocytes via activation of CREB/BDNF axis

OBJECTIVE

Nerve damage can cause severe limb dysfunction and even leave a lifelong disability. The apoptosis of astrocytes may contribute to the nerve damage. In this research, we sought to investigate the effect of β-HB on nerve damage in vitro.

DESIGN

Astrocytes were treated with high glucose (HG) to mimic in vitro model of nerve damage. RT-qPCR and western blot were used to detect expressions of CREB, BDNF, Ki-67, PCNA, Bax, Bcl-2 and cleaved caspase 3 in astrocytes, respectively. MTT was used to measure the cell viability. In addition, flow cytometry was used to detect the cell apoptosis.

RESULTS

β-HB significantly promoted the proliferation and inhibited apoptosis in HG-treated astrocytes. Results showed that of PCNA and Bcl-2 were upregulated, and Bax and cleaved caspase 3 were downregulated after β-HB stimulated in HG-treated astrocytes. In addition, HG-induced inhibition on BDNF expression in astrocytes was notably reversed by β-HB. Furthermore, β-HB promoted the growth and inhibited apoptosis of high glucose-treated astrocytes via activation of CREB/BDNF axis.

CONCLUSION

β-HB promotes the growth and inhibits the apoptosis of high glucose-treated astrocytes via activation of CREB/BDNF axis, which may serve as a new target for treatment of nerve damage.

Resveratrol noncompetitively inhibits glycine receptor-mediated currents in neurons of rat central auditory neurons

Resveratrol, a naturally occurring stilbene found in red wine, is known to modulate the activity of several types of ion channels and membrane receptors, including Ca²⁺, K⁺, and Na⁺ ion channels. However, little is known about the effects of resveratrol on some important receptors, such as glycine receptors and GABA_A receptors, in the central nervous system (CNS). In the present study, the effects of resveratrol on glycine receptor or GABA_A receptor-mediated currents in cultured rat inferior colliculus (IC) and auditory cortex (AC) neurons were studied using whole-cell voltage-clamp recordings. Resveratrol itself did not evoke any currents in IC neurons but it reversibly decreased the amplitude of glycine-induced current (I_Gly) in a concentration-dependent manner. Resveratrol did not change the reversal potential of I_Gly but it shifted the concentration-response relationship to the right without changing the Hill coefficient and with decreasing the maximum response of I_Gly. Interestingly, resveratrol inhibited the amplitude of I_Gly but not that of GABA-induced current (I_GABA) in AC neurons. More importantly, resveratrol inhibited GlyR-mediated but not GABA_AR-mediated inhibitory postsynaptic currents in IC neurons using brain slice recordings. Together, these results demonstrate that resveratrol noncompetitively inhibits I_Gly in auditory neurons by decreasing the affinity of glycine to its receptor. These findings suggest that the native glycine receptors but not GABA_A receptors in central neurons are targets of resveratrol during clinical administrations.

Sirt1 Regulates Oxidative Stress in Oxygen-Glucose Deprived Hippocampal Neurons

Oxidative stress is an important mechanism of neonatal hypoxic-ischemic brain damage. Sirtuin1 (Sirt1) is a deacetylase that depends on NAD⁺, which has an important role in antioxidant metabolism. Furthermore, peroxisome proliferator-activated receptor γ-co-activator 1α (PGC-1α) is a key regulator of mitochondrial oxidative stress, which is regulated by Sirt1. Here, we investigated the role of Sirt1 in the pathogenesis of brain injuries after modulating its activity in primary cultured hippocampal neurons. Our study shows that the expression of Sirt1 was downregulated after oxygen-glucose deprivation. Activation of Sirt1 with resveratrol improved cell's resistance to oxidative stress, whereas inhibition of Sirt1 with EX527 significantly reduced cell viability after cellular oxidative stress. Our study also shows that activation of Sirt1 with resveratrol exerts its antioxidant effect by regulating the expression of PGC-1α. In contrast, application of EX527 decreased the expression of PGC-1α. In summary, these results confirmed that Sirt1 is a potent protective factor for neurons subjected to oxidative stress, and the protective effect of Sirt1 is attributed to its regulation of PGC-1α.