Protective effects of Lavandula stoechas L. methanol extract against 6-OHDA-induced apoptosis in PC12 cells

Chemical profiles and bioactivities of polyphenolic extracts of Lavandula stoechas L., Artemisia dracunculus L. and Ocimum basilicum L

This study assessed the chemical profiles and bioactivities of the infusions, decoctions and hydroethanolic extracts of tarragon, basil and French lavender. The extracts were chemically characterised (HPLC-DAD-ESI/MS) and their bioactivities were evaluated in vitro. All extracts revealed antimicrobial, antifungal and antioxidant properties. French lavender extracts showed higher total phenolic content, regardless of the extraction method used, and antioxidant and antitumour capacities, but no anti-inflammatory action. All basil and two of the tarragon extracts revealed anti-inflammatory power. Thus, tarragon, basil and French lavender extracts may be considered for inclusion in foods, as preservatives or functional ingredients. Nonetheless, further studies must be conducted to evaluate the pharmacokinetic parameters of the bioactive compounds.

Neuroprotection by Polyherbal Medicine Divya-Medha-Vati Against Scopolamine-Induced Cognitive Impairment Through Modulation of Oxidative Stress, Acetylcholine Activity, and Cell Signaling

Alzheimer disease is associated with cognitive impairments and neuronal damages. In this study, Scopolamine, a model drug used for the generation of Alzheimer-like symptoms induced cognitive dysfunction in C57BL/6 mice. It also elevated acetylcholine esterase (AcHE) activity, and reduced antioxidant (superoxide dismutase and catalase) activity in cortex tissue. Scop reduced neuronal density and increased pyknotic neurons in hippocampus tissue. In mouse neuroblastoma (Neuro2a) cells, Scop triggered a dose-dependent loss of cell viability and neurite outgrowth reduction. Scop-treated Neuro2a cells showed oxidative stress and reduction in mRNA expression for brain-derived neurotrophic factor (BDNF), nerve growth factor-1 (NGF-1), and Synapsin-1 (SYN-1) genes. Mice treated with Divya-Medha-Vati (DMV), an Ayurvedic polyherbal medicine showed protection against Scop-induced cognitive impairment (Morris Water Maze Escape Latency, and Elevated Plus Maze Transfer Latency). DMV protected against Scop-induced AcHE activity, and loss of antioxidant activities in the mice brain cortex while sustaining neuronal density in the hippocampus region. In the Neuro2a cells, DMV reduced Scop-induced loss of cell viability and neurite outgrowth loss. DMV protected the cells against induction of oxidative stress and promoted mRNA expression of BDNF, NGF-1, and SYN-1 genes. Phytochemical profiling of DMV showed the presence of Withanolide A, Withanolide B, Bacopaside II, Jujubogenin, Apigenin, Gallic acid, Caffeic acid, and Quercetin that are associated with antioxidant and neurostimulatory activities. In conclusion, the study showed that Divya-Medha-Vati was capable of promoting neuronal health and inhibiting Alzheimer-like cognitive dysfunction through enhanced antioxidant activities and modulation of neuronal activities.

In vitro and Ex vivo study targeting the development of a Lavandula stoechas L. (Ustukhuddūs) loaded Unani Transdermal patch: Implication of Unani Medicine in the treatment of Nisyan (Dementia)

Ustukhuddūs (Lavandula stoechas L.) has been extensively used orally and topically in treating various neurological disorders, including dementia. The optimum potential of traditional dosage forms of Ustukhuddūs is limited for various reasons. Transdermal drug delivery system (TDDS) is a novel means of drug delivery and is known to overcome the drawbacks associated with traditional dosage forms. The current study aimed at fabricating and evaluating Ustukhuddūs hydro-alcoholic extract (UHAE) and essential oil (UEO) loaded matrix-type transdermal patches having a combination of hydrophilic - hydroxyl propyl methyl cellulose (HPMC) and hydrophobic - ethyl cellulose (EC) polymers. ATR-FTIR, DSC, XRD, and SEM analysis were carried out to study drug-polymer interactions, confirming the formation of developed patches and drug compatibility with excipients. We assessed the fabricated patches to evaluate their physicochemical properties, in vitro drug release, and permeation characteristics via ex vivo experiments. The physicochemical characteristics of patches showcased the development of good and stable films with clarity, smoothness, homogeneity, optimum flexibility and free from causing skin irritancy or sensitization. In vitro drug release and ex vivo permeation profile of developed patches were evaluated employing Franz diffusion cells. UHAE and UEO patches exhibited a cumulative drug release of 81.61 and 85.24 %, respectively, in a sustained-release manner and followed non-Fickian release mechanisms. The ex vivo permeation data revealed 66.82 % and 76.41 % of drug permeated from UHAE and UEO patches, respectively. The current research suggests that the formulated patches are more suitable for TDDS and hold potential significance in the treatment of dementia, contributing to enhanced patient compliance, thereby highlighting the implication of Unani Medicine in Nisyan (Dementia) treatment.

Lavandula stoechas extract incorporated polylactic acid nanofibrous mats as an antibacterial and cytocompatible wound dressing

In recent years, great efforts have been devoted to the design and production of bioactive wound dressings that promote skin regeneration and prevent infection. Many plant extracts and essential oils have been widely accepted in traditional medicine for a wide variety of medicinal purposes, especially wound healing. Over the past decade, many studies have focused on manufacturing and designing wound dressings containing plant compounds and extracts. In this study, Lavandula stoechas extract (LSE) (0.25 %, 0.5 %, and 1%wt) incorporated-polylactic acid (PLA) nanofibrous mats were successfully produced and characterized. Microstructural analysis by SEM revealed that the fiber diameter changed with the increase in the amount of LSE. Also, the nanofibrous mats were evaluated for their in vitro antibacterial, cytotoxicity, and wound healing properties for their use as a wound dressing material. According to the results of the disc diffusion test, PLA nanofibrous mats containing LSE %1 showed 9.65 ± 0.46 and 7.37 ± 0.03 inhibition zone (mm) against E. coli and S. aureus, respectively. According to the results of the in vitro wound healing assay, mats containing 0.5 % LSE showed better-wound closure activity compared to the control. Our results show that LSE-incorporated nanofibrous dressings can be an effective alternative with good antimicrobial activity.

Protective effects of fruit extract of Rosa canina and quercetin on human umbilical vein endothelial cell injury induced by hydrogen peroxide

The Nastaran plant, with the scientific name of Rosa canina, has been used since ancient times as a plant with medicinal properties. In the present study, human umbilical vein endothelial cells (HUVECs) were used to examine the protective effects of R. canina fruit extract (RCFE) and its flavonoid ingredient (quercetin) against H2O2-induced cell injury. RCFE (1.25-20 μg/mL) and quercetin (1.25-20 μM) were exposed to H2O2-oxidizing agent (1 and 2 mM) and the protective effect was examined on HUVEC cells by Alamar Blue test. The amount of intracellular reactive oxygen species (ROS) was measured by using DCFDA reagent by fluorimetric method. The effects of RCFE and quercetin on cell apoptosis were studied by staining with hypotonic PI solution and flow cytometry. The amount of PARP and survivin involved in the apoptotic process was measured using the western blot analysis. The results of the Alamar Blue test showed that RCFE and quercetin could reduce the toxicity of H2O2. RCFE and quercetin were able to significantly increase cell viability against H2O2. Also, it was found that RCFE and quercetin reduced the production of ROS by H2O2. It was found that RCFE and quercetin reduced the apoptosis and sub-G1 peak area in flow histogram after exposure of cells to H2O2. Based on western blot results, pretreatment with RCFE and quercetin could significantly increase survivin protein after exposure of cells to H2O2. Also, RCFE and quercetin could significantly reduce the amount of cleaved PARP after exposure of cells to H2O2. RCFE and its ingredient (quercetin) can be considered a promising source of phytochemicals in the prevention of cardiovascular diseases.

Poly (ADP-Ribose) polymerase 1 and parthanatos in neurological diseases: From pathogenesis to therapeutic opportunities

Poly (ADP-ribose) polymerase-1 (PARP-1) is the most extensively studied member of the PARP superfamily, with its primary function being the facilitation of DNA damage repair processes. Parthanatos is a type of regulated cell death cascade initiated by PARP-1 hyperactivation, which involves multiple subroutines, including the accumulation of ADP-ribose polymers (PAR), binding of PAR and apoptosis-inducing factor (AIF), release of AIF from the mitochondria, the translocation of the AIF/macrophage migration inhibitory factor (MIF) complex, and massive MIF-mediated DNA fragmentation. Over the past few decades, the role of PARP-1 in central nervous system health and disease has received increasing attention. In this review, we discuss the biological functions of PARP-1 in neural cell proliferation and differentiation, memory formation, brain ageing, and epigenetic regulation. We then elaborate on the involvement of PARP-1 and PARP-1-dependant parthanatos in various neuropathological processes, such as oxidative stress, neuroinflammation, mitochondrial dysfunction, excitotoxicity, autophagy damage, and endoplasmic reticulum (ER) stress. Additional highlight contains PARP-1's implications in the initiation, progression, and therapeutic opportunities for different neurological illnesses, including neurodegenerative diseases, stroke, autism spectrum disorder (ASD), multiple sclerosis (MS), epilepsy, and neuropathic pain (NP). Finally, emerging insights into the repurposing of PARP inhibitors for the management of neurological diseases are provided. This review aims to summarize the exciting advancements in the critical role of PARP-1 in neurological disorders, which may open new avenues for therapeutic options targeting PARP-1 or parthanatos.

Neuroprotective Capability of Narcissoside in 6-OHDA-Exposed Parkinson's Disease Models through Enhancing the MiR200a/Nrf-2/GSH Axis and Mediating MAPK/Akt Associated Signaling Pathway

We assessed the antioxidant potential of narcissoside from Sambucus nigra flowers (elderflowers) in Parkinson's disease models in vitro and in vivo. The results showed that narcissoside lessened the 6-hydroxydopamine (6-OHDA)-induced increase in reactive oxygen species (ROS) and apoptosis in SH-SY5Y cells. In the 6-OHDA-exposed Caenorhabditis elegans model, narcissoside reduced degeneration of dopaminergic neurons and ROS generation, and also improved dopamine-related food-sensitive behavior and shortened lifespan. Moreover, NCS increased total glutathione (GSH) by increasing the expression of the catalytic subunit and modifier subunit of γ-glutamylcysteine ligase in cells and nematodes. Treatment with a GSH inhibitor partially abolished the anti-apoptotic ability of narcissoside. Furthermore, narcissoside diminished the 6-OHDA-induced phosphorylation of JNK and p38, while rising activities of ERK and Akt in resisting apoptosis. The antioxidant response element (ARE)-luciferase reporter activity analysis and electromobility gel shift assay showed that narcissoside promotes the transcriptional activity mediated by Nrf2. Finally, we found that narcissoside augmented the expression of miR200a, a translational inhibitor of the Nrf2 repressor protein Keap1. Downregulation of Nrf2 and miR200a by RNAi and anti-miR200a, respectively, reversed the neuroprotective ability of narcissoside. In summary, narcissoside can enhance the miR200a/Nrf2/GSH antioxidant pathway, alleviate 6-OHDA-induced apoptosis, and has the neuroprotective potential.

Norlignans and phenolics from genus Curculigo protect corticosterone-injured neuroblastoma cells SH-SY5Y by inhibiting endoplasmic reticulum stress-mitochondria pathway

ETHNOPHARMACOLOGICAL RELEVANCE

The plants of genus Curculigo are divided into the Section Curculigo and the Section Capitulata, which are mainly distributed in southeastern and southwestern China. Various ancient chinese books record that these plants were used as an important herb for tonifying kidney yang. Traditional Chinese medicine often draws on this property to treat depression syndrome. Thus genus Curculigo has potential for the treatment of neurodegenerative diseases (ND). The study showed that phenolics were the main characteristic components of plants in the Section Curculigo, represented by orcinol glucoside and curculigoside; the norlignans, with Ph-C5-Ph as the basic backbone, were the main characteristic components of the Section Capitulata. However, there is a lack of sufficient scientific evidence as to whether these two types of ingredients have neuroprotective effects.

AIM OF THE STUDY

To determine the neuroprotective effects of phenolics and norlignans in genus Curculigo on human neuroblastoma cells SH-SY5Y. To discuss their structure-activity relationship and screen for compounds with high activity and neuroprotective effects. To reveal that the amelioration of endoplasmic reticulum (ER) stress by two classes of compounds is mediated by the PERK/eIF2α/ATF4 pathway.

MATERIALS AND METHODS

The cytotoxicity of 17 compounds was assayed by MTT. SH-SY5Y cells were damaged by corticosterone (Cort) (200 μM) for 24 h and then co-administered with 17 compounds (0.1-100 μM) and Cort (200 μM) for 24 h. Cell survival was determined by MTT assay. Apoptosis rate, mitochondrial membrane potential (MMP) and intracellular reactive oxygen species (ROS) levels were detected using flow cytometry. Intracellular Ca²⁺ levels were detected using a fluorescent probe. Cellular mitochondrial and ER damage was observed using transmission electron microscopy (TEM). ER stress and apoptotic pathway-related proteins (BiP, CHOP, cleaved caspase-3, cleaved caspase-9, Bax/Bcl-2), and the expression level of PERK/eIF2α/ATF4 pathway was measured via western blot (WB).

RESULTS

The experimental data showed that Cort treatment of SH-SY5Y cells resulted in decreased cell survival and increased apoptosis, mitochondrial depolarization, ROS, and intracellular Ca²⁺ levels. The co-action of 17 compounds and Cort for a period of time significantly increased cell survival. Compounds 3, 7, 12, 13 also reduced apoptosis rate, mitochondrial depolarization, ROS and intracellular Ca²⁺ levels in the subsequent experiments. In addition, TEM observed that Cort caused mitochondrial and ER damage, and the damage was improved after treatment. WB analysis obtained that Cort increased the expression of apoptotic and ER stress-related proteins and activated pathway expression. However, in the presence of compounds 3, 7, 12, 13, the expression of BiP, CHOP, cleaved caspase-3, cleaved caspase-9, and Bax/Bcl-2 was significantly reduced, and the phosphorylation of PERK and eIF2α and the expression of ATF4 were inhibited.

CONCLUSION

This study found that one phenolic (3) and three norlignans (7, 12, 13) from genus Curculigo have significant neuroprotective effects. The results of the structure-activity relationship indicated that the glucosyl polymeric norlignans and the phenolics with benzoic acid as the parent nucleus were more active. The neuroprotective effect of three norlignans is the latest discovery. This finding has important research value in the field of prevention and treatment of neurodegenerative diseases.

In vitro and in vivo neuroprotective effect of novel mPGES-1 inhibitor in animal model of Parkinson's Disease

mPGES-1 is found to be up-regulated in the dopaminergic neurons of the substantia nigra pars compacta (SNpc) of postmortem brain tissue from Parkinson's disease (PD) patients and neurotoxin 6-hydroxydopamine (6-OHDA)-induced PD mice. Since the genetic deletion of mPGES-1 abolished 6-OHDA-induced PGE₂ production and 6-OHDA-induced dopaminergic neurodegeneration in vitro and in vivo models, mPGES-1 enzyme has the potential to be an important target for PD therapy. In the present work, we investigated whether a small organic molecule as mPGES-1 inhibitor could exhibit the neuroprotective effects against 6-OHDA-induced neurotoxicity in in vitro and in vivo models. For this research goal, a new series of arylsulfonyl hydrazide derivatives was prepared and investigated whether these compounds may protect neurons against 6-OHDA-induced neurotoxicity in both in vitro and in vivo studies. Among them, compound 7s (MPO-0144) as a mPGES-1 inhibitor (PGE₂ IC₅₀ = 41.77 nM; mPGES-1 IC₅₀ = 1.16 nM) exhibited a potent neuroprotection (ED₅₀ = 3.0 nM) against 6-OHDA-induced in PC12 cells without its own neurotoxicity (IC₅₀ = >10 μM). In a 6-OHDA-induced mouse model of PD, administration of compound 7s (1 mg/kg/day, for 7days, i.p.) ameliorated motor impairments and dopaminergic neuronal damage. These significant biological effects of compound 7s provided the first pharmacological evidence that mPGES-1 inhibitor could be a promising therapeutic agent for PD patients.

Protective effects of 6-gingerol on 6-hydroxydopamine-induced apoptosis in PC12 cells through modulation of SAPK/JNK and survivin activation

Due to many therapeutic effects, Ginger (Zingiber officinale) is the most widely used spice around the world, including in Iran. Due to its potent anti-inflammatory and antioxidant effects, ginger may protect against neurodegenerative disorders. Here, we investigated the effects of 6-gingerol (the main bioactive compound in ginger) on 6-hydroxydopamine (6-OHDA)-induced cell death in PC12 cells. Cell viability, cell apoptosis, and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), and survivin expression were measured using resazurin, propidium iodide (PI) and flow cytometry, and western blot analysis. 6-OHDA (100 μM) reduced the cell viability, increased apoptosis, increased the active form of SAPK/JNK, and decreased survivin protein level in PC12 exposed cells in a dose and time-dependent manner. Pretreatment with 6-gingerol significantly increased the viability and reduced apoptosis (2.5 and 5 µM). Also, pretreatment with 6-gingerol at 2.5 and 5 µM increased survivin whereas, 6-gingerol at 2.5 µM reduced (P-SAPK/JNK):(SAPK/JNK) levels to a level near that of the related control. According to the results, 6-gingerol blocks 6-OHDA-induced cell damage by suppressing oxidative stress and anti-apoptotic activity. Thus, 6-gingerol may process beneficial protective effects in slowing the progression of Parkinson's disease.