Silibinin Protects against H2O2-Induced Oxidative Damage in SH-SY5Y Cells by Improving Mitochondrial Function

Photobiomodulation by LED 660 nm and Taurine against H2O2 oxidative stress in SH-SY5Y cells

Alzheimer's Disease (AD) is a progressive uncurable neurodegenerative pathology affecting millions worldwide. Photobiomodulation and Taurine are promising alternatives for preventing and reducing the rapid progression of neurodegeneration, stimulating the reconstructing of neural tissue structures, especially improving mitochondrial activity, which is highly impaired in AD. In this study, the mitochondrial effects of Taurine combined with light emitting diode (LED) irradiation were evaluated on human neuroblastoma cells (SH-SY5Y), under oxidative stress condition by hydrogen peroxide (H2O2) exposure, a considerable modulator in AD. We evaluated LED irradiation at the wavelength of 660 nm and Taurine under different concentrations before and together with exposing SH-SY5Y cells to different concentrations of H2O2, assessing mitochondrial activity by the MTT colorimetric test and labeling live cells mitochondria by the fluorescent probe MitoTracker. Cell viability was also evaluated by the trypan blue exclusion assay, and cellular morphological structures were imaged by scanning electron microscopy (SEM). Neuroprotective effects were achieved by both LED irradiation and LED irradiation + Taurine when cells were exposed to them before H2O2-induced stress. Comparing both agents, LED irradiation at 660 nm is sufficient to improve mitochondrial activity, however, healthy mitochondrial morphology was only observed when cells were treated with Taurine together with LED irradiation, representing affordable candidates that act in synergy against oxidative stress, one of the main contributors to neurodegeneration.

Sirtuin 1 Is a Potential Target for the Treatment of Neurogenic Intermittent Claudication by Modulating Pyroptosis

Neurogenic intermittent claudication (NIC) pathogenesis associated with lumbar spinal stenosis (LSS) remains unclear. However, pyroptosis has been implicated in the pathogenesis of various central nervous system disorders. Therefore, the present study aimed to explore the potential role of pyroptosis in NIC progression. Additionally, the present study investigated the possible involvement of Sirtuin 1 (Sirt1), a protein recognized for its neuroprotective properties, in mitigating the progression of NIC by alleviating pyroptosis. In the current study, a rat model of NIC associated with LSS was successfully constructed by inserting a silicone strip into the vertebral plates. The Basso Beattie Bresnahan score was employed to assess the motor function of rats. Western blot analysis was performed to measure the levels of pyroptosis-related proteins in rat spinal cord tissue. Meanwhile, PC-12 cells were cultured with H2O2 to establish an in vitro model of oxidative stress, allowing to investigate the effects of Sirt1 on cell pyroptosis and oxidative stress in H2O2-treated cells. The current results showed that rats with NIC developed both motor and sensory dysfunction. Additionally, NIC surgery notably elevated NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), gasdermin D N-terminal (GSDMD-N), and IL-1β levels in the spinal cord tissues of rats, suggesting that pyroptosis is activated in the context of NIC. Significantly, downregulation of Sirt1 exacerbated malondialdehyde and reactive oxygen species levels, and simultaneously reduced GSH levels in H2O2-stimulated PC-12 cells, suggesting that Sirt1 deficiency can aggravate oxidative stress. Meanwhile, downregulation of Sirt1 also led to increased levels of NLRP3, ASC, GSDMD-N, and cleaved caspase 1 in H2O2-stimulated PC-12 cells, suggesting that Sirt1 deficiency can further enhance the pyroptosis in these cells. Targeting pyroptosis signaling may yield new insights into the treatment of NIC. The mechanisms mediated by pyroptosis could offer valuable perspectives on the pathogenesis and management of this condition.

Sulfonic acid functionalized β-amyloid peptide aggregation inhibitors and antioxidant agents for the treatment of Alzheimer's disease: Combining machine learning, computational, in vitro and in vivo approaches

Alzheimer's disease (AD) is characterized as a neurodegenerative disorder that is caused by plaque formation by accumulating β-amyloid (Aβ), leading to neurocognitive function and impaired mental development. Thus, targeting Aβ represents a promising target for the development of therapeutics in AD management. Several functionalized sulfonic acid molecules have been reported, including tramiprosate prodrug, which is currently in clinical trial III and exhibits a good response in mild to moderate AD patients. Therefore, expanding upon this approach, we hypothesized that the sulfonic acid functionalized aromatic class molecule might demonstrate a good inhibitory effect against β-amyloid aggregation, leading to a decrease in the progression burden of AD. We used computational and in vitro approaches to establish effective compounds. As a result, three potent hit molecules were selected based on binding score as well as availability. In the case of safety profile of compounds, in vitro using human neuroblastoma SH-SY5Y cells and in vivo using C. elegans was performed at doses up to 500 μM; no difference in viability was exhibited between control and treatment groups. However, H2O2-induced ROS stress was significantly reduced in neuroblastoma cells after treatment. The AFM and ThT-embedded β-amyloid1-42 kinetic studies confirmed B-PEA-MBSA and H-HPA-NSA potency. H-HPA-NSA arrested elongation phase of Aβ aggregation in kinetic study at a lower concentration (10 μM), while B-PEA-MBSA reduced the intensity of stationary phase at a dose of 100 μM. Thus, based on the outcomes, it can be suggested that B-PEA-MBSA and H-HPA-NSA can prevent β-amyloid aggregation with mild to moderate AD.

In vitro and in silico anti-Alzheimer study of rutin embedded with zinc chloride loaded bovine serum albumin nanoparticles

Nanotechnology-based herbal drug formulations that target multiple aspects of the disease are one of the possible approaches to address the pathological intricacies of Alzheimer's disease (AD). The present study includes the development of rutin embedded with zinc chloride-loaded bovine serum albumin nanoparticles (R-BSA-ZnCl2 NPs) to counter AD pathogenesis. In this work, the anti-AD potential of selected Phyto active (Rutin) was investigated using a high throughput in silico screening technique. Characterisation and optimization of the formulation were performed by different analytical methods such as FT-IR, zeta sizer and zeta potential, SEM analysis, thermal analysis, x-ray diffraction technique, etc. In vitro, free radical scavenging assay of the formulation was performed using a DPPH assay, and the ROS quantification was done by taking the RAW cell line. The amyloid β disaggregation study was confirmed by the thioflavin T assay, and the blood-brain barrier permeability assay was performed by taking brain endothelial cells. An anticholinesterase study was conducted to ascertain the formulation's potential for treating Alzheimer's disease. The NPs was prepared by ion gelation method and characterized for size (164.8 ± 5.6 nm), zeta potential (-29.6 mV), encapsulation efficiency (91 ± 1.1 %) and loading capacity (10 ± 0.2 %). The FTIR analysis indicated that there was no chemical interaction between the functional groups of rutin and other excipients. DSC, XRD studies suggested unchanged physical state of rutin in the prepared nanoparticle. Surface characterization analysed the irregular morphology of the nanoparticle. The antioxidant activity by DPPH and FRAP assay demonstrated a significant increase in free radical scavenging for R-BSA-ZnCl2 NPs in compared to rutin (p < 0.01). Anti-aggregation studies indicated that the nanoparticle inhibited the Aβ fibrils by over 70-80 %, as confirmed by Thioflavin T assay. Moreover, the blood brain barrier (BBB) permeability assay indicated permeation of nanoparticle via BBB. Thus, the present study highlighted that bovine serum albumin-zinc chloride nanoparticle may be used as a multifactorial therapeutic platform to address neurodegeneration associated with cognition.

Cisplatin-induced acute kidney injury increased brain 5-hydroxytryptamine levels partly due to the hippuric acid-induced upregulation of CYP2D4 expression and function in the brain of rats

Patients with acute kidney injury (AKI) are often associated with uremic encephalopathy, but its underlying mechanisms remain unclear. This study aimed to investigate how AKI induced neuropsychiatric disorders through cerebral 5-hydroxytryptamine (5-HT) dysregulation in cisplatin-induced AKI rats. Our findings demonstrated that AKI induced anxiety-like behaviors and increased cerebral 5-HT levels, which may be attributed to the upregulated CYP2D4 expression and activity. The intraventricular injection of quinine (CYP2D4 inhibitor) attenuated the elevated cortical 5-HT levels in AKI rats. Intraperitoneal administration of 5-methoxytryptamine (CYP2D4 substrate) also provoked anxiety-like behaviors and cerebral 5-HT accumulation, which were reversed by cotreatment with quinine. Hippuric acid (HA), as a classical uremic toxin, was severely accumulated in both the plasma and brain of AKI rats. In vitro experiments demonstrated that HA-induced reactive oxygen species (ROS) upregulated expression of CYP2D6 (over 70% homology with rat CYP2D4) via suppressing Nrf2/HO-1 pathway in SH-SY5Y cells. These effects were reversed by ROS scavenger N-acetylcysteine, Nrf2 activator sulforaphane, and HO-1 activator cobalt-protoporphyrin IX. Similarly, either Nrf2 inhibitor ML385 or HO-1 inhibitor zinc-protoporphyrin IX exerted up-regulatory effects on CYP2D6 expression. In vivo studies confirmed that HA treatment induced AKI-like behavioral abnormalities in rats, accompanied by increased cerebral 5-HT levels and CYP2D4 expression as well as induced production of ROS, decreased Nrf2 and HO-1 protein levels. Our findings elaborate a novel mechanism between kidney failure and neuropsychiatric complications. Specifically, cisplatin-induced AKI upregulates CYP2D4 expression via HA-mediated ROS release, subsequently promoting generation of cerebral 5-HT by CYP2D4 and revealing material basis of AKI-associated uremic encephalopathy. SIGNIFICANCE STATEMENT: This study revealed that the psychiatric disorders of cisplatin-induced acute kidney injury rats are partly attributed to the increased 5-hydroxytryptamine levels induced by brain CYP2D. The induction of CYP2D4 is mainly due to brain accumulation of hippuric acid via inactivation of Nrf2/HO-1 pathway by reactive oxygen species.

Human serum albumin-3-amino-1-propanesulfonic acid conjugate inhibits amyloid-β aggregation and mitigates cognitive decline in Alzheimer's disease

Alzheimer's disease (AD) is the most commonly occurring brain disorder, characterized by the accumulation of amyloid-β (Aβ) and tau, subsequently leading to neurocognitive decline. 3-Amino-1-propanesulfonic acid (TPS) and its prodrug, currently under clinical trial III, serve as promising therapeutic agents targeting Aβ pathology by specifically preventing monomer-to-oligomer formation. Inspired by the potency of TPS prodrug, we hypothesized that conjugating TPS with human serum albumin (HSA) could enhance brain delivery and synergistically inhibit Aβ aggregation in mild to moderate AD. Thus, we prepared and extensively characterized HSA-TPS (h-TPS) conjugate using an eco-friendly coupling method. In vitro studies on Aβ aggregation kinetics and AFM imaging revealed significant prevention of Aβ aggregation. Additionally, h-TPS significantly reduced Aβ-induced neurotoxicity and H2O2-mediated reactive oxygen species (ROS) stress in SH-SY5Y cells. Moreover, h-TPS administration improved blood-brain barrier permeability and cellular uptake into neuronal cells as well as showed in vivo uptake inside the brain within 1 h. In vivo studies using an Aβ1-42-induced acute AD rat model exhibited a dose-dependent significant reduction in hippocampal Aβ levels and restoration of declined spatial learning and memory with h-TPS treatment. Overall, findings suggest that h-TPS conjugate might be a promising neuroprotective agent for preventing Aβ aggregation in mild to moderate AD.

Protective potentials of extracted compound SILIBININ from milk thistle on type-2 diabetes mellitus and diesel exhaust particle (DEP) toxicity in experimental rats

The combustion of diesel in engines contributes polycyclic aromatic hydrocarbons to Diesel Particulate Matter (DPM) present in the atmosphere, therefore causing toxic mitigating consequences by eliciting oxidative modulation. Currently, type 2 diabetes mellitus is reported as a global menace, causing about 1.5 million deaths in 2019 and contributing to about 48% of related deaths among the populace aged below 70 years. (GBDCN, 2020). Silibinin (SIL) is a flavolignan from milk thistle with substantive therapeutic potential. This work elucidates the effects of SIL on glucose modulatory pathways (PI3K-AKT-GLUT 2 and AMPK-GLUT 2), inflammation and redox imbalance in the pancreas of diabetic rats subjected to DEP. Streptozocin was used to induce Type-2 diabetes mellitus in rats, which were further endangered to DEP (0.4 and 0.5 mg/kg) later, post-treated with SIL 40 mg/kg. For comparison, a parallel group of nondiabetic rats were exposed to DEP and afterwards treated with SIL, whilst the results were compared to the diabetic group. Results state that SIL leads to marked/substantial modulation in insulin-associated genes (PI3K, AKT, AMPK, GLUT 2), inflammatory markers (IL-1β, IL-10), peroxidation (MDA, CD) and antioxidative status (SOD, CAT, GPX, GSH, HO-1) in vivo as negatively induced by DEP and hyperglycaemia, thereby restoring glucose homeostasis. Taken together, SIL proffers the potential to ameliorate pancreatic-toxicity caused by DEP and high blood glucose/elevated glucose levels.

Plant Secondary Metabolites as Modulators of Mitochondrial Health: An Overview of Their Anti-Oxidant, Anti-Apoptotic, and Mitophagic Mechanisms

Plant secondary metabolites (PSMs) are a diverse group of bioactive compounds, including flavonoids, polyphenols, saponins, and terpenoids, which have been recognised for their critical role in modulating cellular functions. This review provides a comprehensive analysis of the effects of PSMs on mitochondrial health, with particular emphasis on their therapeutic potential. Emerging evidence shows that these metabolites improve mitochondrial function by reducing oxidative stress, promoting mitochondrial biogenesis, and regulating key processes such as apoptosis and mitophagy. Mitochondrial dysfunction, a hallmark of many pathologies, including neurodegenerative disorders, cardiovascular diseases, and metabolic syndrome, has been shown to benefit from the protective effects of PSMs. Recent studies show that PSMs can improve mitochondrial dynamics, stabilise mitochondrial membranes, and enhance bioenergetics, offering significant promise for the prevention and treatment of mitochondrial-related diseases. The molecular mechanisms underlying these effects, including modulation of key signalling pathways and direct interactions with mitochondrial proteins, are discussed. The integration of PSMs into therapeutic strategies is highlighted as a promising avenue for improving treatment efficacy while minimising the side effects commonly associated with synthetic drugs. This review also highlights the need for future research to elucidate the specific roles of individual PSMs and their synergistic interactions within complex plant matrices, which may further optimise their therapeutic utility. Overall, this work provides valuable insights into the complex role of PSMs in mitochondrial health and their potential as natural therapeutic agents targeting mitochondrial dysfunction.

Protective Effect of Arzanol against H2O2-Induced Oxidative Stress Damage in Differentiated and Undifferentiated SH-SY5Y Cells

Oxidative stress can damage neuronal cells, greatly contributing to neurodegenerative diseases (NDs). In this study, the protective activity of arzanol, a natural prenylated α-pyrone-phloroglucinol heterodimer, was evaluated against the H2O2-induced oxidative damage in trans-retinoic acid-differentiated (neuron-like) human SH-SY5Y cells, widely used as a neuronal cell model of neurological disorders. The pre-incubation (for 2 and 24 h) with arzanol (5, 10, and 25 μM) significantly preserved differentiated SH-SY5Y cells from cytotoxicity (MTT assay) and morphological changes induced by 0.25 and 0.5 mM H2O2. Arzanol reduced the generation of reactive oxygen species (ROS) induced by 2 h oxidation with H2O2 0.5 mM, established by 2',7'-dichlorodihydrofluorescein diacetate assay. The 2 h incubation of differentiated SH-SY5Y cells with H2O2 determined a significant increase in the number of apoptotic cells versus control cells, evaluated by propidium iodide fluorescence assay (red fluorescence) and NucView® 488 assay (green fluorescence). Arzanol pre-treatment (2 h) exerted a noteworthy significant protective effect against apoptosis. In addition, arzanol was tested, for comparison, in undifferentiated SH-SY5Y cells for cytotoxicity and its ability to protect against H2O2-induced oxidative stress. Furthermore, the PubChem database and freely accessible web tools SwissADME and pkCSM-pharmacokinetics were used to assess the physicochemical and pharmacokinetic properties of arzanol. Our results qualify arzanol as an antioxidant agent with potential neuroprotective effects against neuronal oxidative stress implicated in NDs.

Kaempferol Derivatives from Hippophae rhamnoides Linn. Ameliorate H2O2-Induced Oxidative Stress in SH-SY5Y Cells by Upregulating Nrf2

As a medicinal and edible resource, Hippophae rhamnoides Linn. subsp. sinensis Rousi is rich in bioactive secondary metabolites, including flavonoids and their derivatives, which offer protective effects against oxidative damage. This study reported the isolation of three new kaempferol derivatives from the seed residue of H. rhamnoides - Hippophandine A, B, and C (compounds 1-3). Their structures were elucidated by high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), nuclear magnetic resonance (NMR), and chemical analyses. The compounds were evaluated for their ability to mitigate hydrogen peroxide (H2O2)-induced cell death in SH-SY5Y cells. The results elucidated that Hippophandine A-C at concentrations of 1, 5, and 10 μM reduced the levels of malondialdehyde (MDA) and increased the activity of antioxidative enzymes, such as superoxide dismutase (SOD), glutathione (GSH), and catalase (CAT). Furthermore, they significantly altered the protein expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream heme oxygenase-1 (HO-1), which is an indicator of redox detection in H2O2-induced SH-SY5Y.

Chitosan Nanoparticles Loaded with Quercetin and Valproic Acid: A Novel Approach for Enhancing Antioxidant Activity against Oxidative Stress in the SH-SY5Y Human Neuroblastoma Cell Line

BACKGROUND

Multiple drug-delivery systems obtained by loading nanoparticles (NPs) with different drugs that have different physicochemical properties present a promising strategy to achieve synergistic effects between drugs or overcome undesired effects. This study aims to develop a new NP by loading quercetin (Que) and valproic acid (VPA) into chitosan. In this context, our study investigated the antioxidant activities of chitosan NPs loaded with single and dual drugs containing Que against oxidative stress.

METHOD

The synthesis of chitosan NPs loaded with a single (Que or VPA) and dual drug (Que and VPA), the characterization of the NPs, the conducting of in vitro antioxidant activity studies, and the analysis of the cytotoxicity and antioxidant activity of the NPs in human neuroblastoma SH-SY5Y cell lines were performed.

RESULT

The NP applications that protected cell viability to the greatest extent against H2O2-induced cell damage were, in order, 96 µg/mL of Que-loaded chitosan NP (77.30%, 48 h), 2 µg/mL of VPA-loaded chitosan NP (70.06%, 24 h), 96 µg/mL of blank chitosan NP (68.31%, 48 h), and 2 µg/mL of Que- and VPA-loaded chitosan NP (66.03%, 24 h).

CONCLUSION

Our study establishes a successful paradigm for developing drug-loaded NPs with a uniform and homogeneous distribution of drugs into NPs. Chitosan NPs loaded with both single and dual drugs possessing antioxidant activity were successfully developed. The capability of chitosan NPs developed at the nanometer scale to sustain cell viability in SH-SY5Y cell lines implies the potential of intranasal administration of chitosan NPs for future studies, offering protective effects in central nervous system diseases.

Ion-activated In Situ Gel of Gellan Gum Containing Chrysin for Nasal Administration in Parkinson's Disease

INTRODUCTION

This study focused on creating an innovative treatment approach for Parkinson's disease (PD), a progressive neurodegenerative condition characterized by the loss of specific neurons in the brain.

AIM

The research aimed to develop a nasal gel using gellan gum containing a complex of chrysin with hydroxypropyl-β-cyclodextrin (HP-β-CD) to enhance the drug's solubility and stability.

METHOD

The formulation process involved utilizing central composite design (CCD) to optimize the concentrations of gellan gum and HPMC E5, with viscosity and mucoadhesive strength as key factors. The resulting optimized In Situ gel comprised 0.7% w/v gellan gum and 0.6% w/v HPMC E5, exhibiting desirable viscosity levels for both sol and gel states, along with robust mucoadhesive properties. The formulated gel underwent comprehensive evaluation, including assessments for gelation, drug content, in vitro drug release, ex vivo permeation, and histopathology.

RESULT

The findings demonstrated superior drug release from the In Situ gel compared to standalone chrysin. Ex vivo studies revealed effective drug permeation through nasal mucosa without causing harm. Moreover, experiments on neuronal cells exposed to oxidative stress (H2O2- induced) showcased significant neuroprotection conferred by chrysin and its formulations. These treatments exhibited notable enhancements in cell viability and reduced instances of apoptosis and necrosis, compared to the control group. The formulations exhibited neuroprotective properties by mitigating oxidative damage through mechanisms, like free radical scavenging and restoration of antioxidant enzyme activity.

CONCLUSION

In conclusion, this developed In situ gel formulation presents a promising novel nasal delivery system for PD therapy. By addressing challenges related to drug properties and administration route, it holds the potential to enhance treatment outcomes and improve the quality of life for individuals with Parkinson's disease.

Modulation of cytotoxic amyloid fibrillation and mitochondrial damage of α-synuclein by catechols mediated conformational changes

The interplay between α-synuclein (α-syn) and catechols plays a central role in Parkinson's disease. This may be related to the modulating effects of catechols on the various aspects of α-syn fibrillization. Some of these effects may be attributed to the membrane-binding properties of the protein. In this work, we compare the effect of some catechols, including dopamine, epinephrine, DOPAL, and levodopa in micromolar concentrations, on the in vitro cytotoxicity of α-syn fibrils on human neuroblastoma SH-SY5Y cells. The study was followed by comparing the interactions of resulting structures with rat brain mitochondria used as an in vitro biological model. The obtained results demonstrate that catechols-induced structures have lost their cytotoxicity mimicking apoptotic cell death mediated by α-syn aggregates in different proportions. Moreover, α-syn fibrils-induced mitochondrial dysfunction, evaluated by a range of biochemical assays, was modulated by catechols-modified α-syn oligomers in different manners, as levodopa and DOPAL demonstrated the maximal and minimal effects, respectively. The plausible mechanism causing the inhibition of α-syn cytotoxic fibrillization and mitochondrial dysfunction by catechols is discussed. Taken together, we propose that catechols can prevent the cytotoxic assembly of α-syn and its destructive effects on mitochondria at various stages, suggesting that decreased levels of catechols in dopaminergic neurons might accelerate the α-syn cytotoxicity and mitochondrial dysfunction implicating Parkinson's disease.

Role of Plant-Derived Compounds in the Molecular Pathways Related to Inflammation

Inflammation is the primary response to infection and injury. Its beneficial effect is an immediate resolution of the pathophysiological event. However, sustained production of inflammatory mediators such as reactive oxygen species and cytokines may cause alterations in DNA integrity and lead to malignant cell transformation and cancer. More attention has recently been paid to pyroptosis, which is an inflammatory necrosis that activates inflammasomes and the secretion of cytokines. Taking into consideration that phenolic compounds are widely available in diet and medicinal plants, their role in the prevention and support of the treatment of chronic diseases is apparent. Recently, much attention has been paid to explaining the significance of isolated compounds in the molecular pathways related to inflammation. Therefore, this review aimed to screen reports concerning the molecular mode of action assigned to phenolic compounds. The most representative compounds from the classes of flavonoids, tannins, phenolic acids, and phenolic glycosides were selected for this review. Our attention was focused mainly on nuclear factor-κB (NF-κB), nuclear factor erythroid 2-related factor 2 (Nrf2), and mitogen-activated protein kinase (MAPK) signaling pathways. Literature searching was performed using Scopus, PubMed, and Medline databases. In conclusion, based on the available literature, phenolic compounds regulate NF-κB, Nrf2, and MAPK signaling, which supports their potential role in chronic inflammatory disorders, including osteoarthritis, neurodegenerative diseases, cardiovascular, and pulmonary disorders.