Renshen Shouwu extract enhances neurogenesis and angiogenesis via inhibition of TLR4/NF-κB/NLRP3 signaling pathway following ischemic stroke in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Renshen Shouwu extract (RSSW) is a patented Traditional Chinese Medicine included in Chinese Pharmacopoeia for neurasthenia, forgetfulness, insomnia, inappetence and excessive fatigue. Our previous study had demonstrated the neuroprotective effect of RSSW against ischemic stroke in rats with middle cerebral artery occlusion (MCAO). However, its underlying mechanism remains unknown.

AIM OF THE STUDY

In this study, we investigated the neurogenesis and angiogenesis effects of RSSW in ischemic stroke rats, and further revealed its underlying mechanism focused on TLR4/NF-κB/NLRP3 signaling pathway.

MATERIALS AND METHODS

Firstly, active compounds of RSSW were determined by High Performance Liquid Chromatography (HPLC). Secondly, Middle cerebral artery occlusion (MCAO) was performed to induce ischemic stroke in rats and 2, 3, 5-Triphenyltetrazolium chloride (TTC) staining was employed to evaluate whether MCAO surgery was successfully established. Neurological deficit evaluation was conducted according to the Zea Longa' method. Then, we explored the neurogenesis and angiogenesis effects after oral administration of RSSW (50 mg/kg, 100 mg/kg) in MCAO-induced rats by Immunofluorescence Staining. Moreover, the proteins involved in TLR4/NF-κB/NLRP3 signaling pathway (TLR4, p-NF-κB p65, NF-κB p65, NLRP3, pro-IL-1β, IL-1β, pro-Caspase-1, Caspase-1) were determined by western blotting.

RESULTS

It was observed that RSSW treatment significantly increased the number of newborn neurons and brain microvessel density (MVD) after ischemic stroke. What's more, RSSW treatment significantly downregulated TLR4, p-NF-κB p65/p65, NLRP3, pro-IL-1β, IL-1β, pro-Caspase-1, Caspase-1 proteins involved in TLR4/NF-κB/NLRP3 signaling pathway.

CONCLUSIONS

RSSW enhances neurogenesis and angiogenesis via inhibition of TLR4/NF-κB/NLRP3 inflammatory signaling pathway following ischemic stroke in rats. Hence, RSSW may be a promising Chinese Medicine for the treatment of ischemic stroke.

Harpagide from Scrophularia protects rat cortical neurons from oxygen-glucose deprivation and reoxygenation-induced injury by decreasing endoplasmic reticulum stress

ETHNOPHARMACOLOGICAL RELEVANCE

Harpagide is the main ingredient in Scrophularia ningpoensis Hemsl which is used for the therapeutic purpose of treating encephalopathy. Harpagide has shown promise in the treatment of oxygen-glucose deprivation and reoxygenation (OGD/R)-induced brain injury. However, the underlying mechanisms remain unclear.

AIM OF STUDY

In this study, we aimed to determine the neuroprotective effect of harpagide on rat cortical neurons under OGD/R conditions that induce the development of ischaemia-reperfusion (I/R).

MATERIALS AND METHODS

To explore the biological function of harpagide in cerebral ischaemia-reperfusion injury (CIRI), The CIRI model was established by oxygen-glucose deprivation and reoxygenation (OGD/R) on rat cortical neurons. It tested cell survival rate by 3-(4,5-dimethylthiazol-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, apoptosis by flow cytometry, intracellular Ca²⁺ concentration [Ca²⁺] _i by cofocal laser, and expressions related to endoplasmic reticulum stress (ERS) by RT-PCR and Western blot.

RESULTS

We found that pretreatment with harpagide (50 μM) prevented OGD/R-induced apoptotic cell death. Harpagide also significantly decreased the gene expression levels and protein production of ERS-related proteins. We found that harpagide also exerted a neuroprotective effect on TG-induced apoptosis in rat cortical neurons and decreased the gene expression levels and protein production of GRP78, caspase-12 and CHOP. We also measured the intracellular calcium ion concentration ([Ca²⁺]_i) in neurons and found that harpagide significantly decreased the [Ca²⁺]_i induced by OGD/R and TG.

CONCLUSION

These results suggest that harpagide protects against OGD/R-induced cell apoptosis, likely by decreasing ERS. Collectively, harpagide was demonstrated to be a prominent suppressor of ERS and prevented the apoptosis of rat cortical neurons. Based on the results, harpagide could potentially serve as a therapeutic agent of ischaemia-like injury associated with excessive ERS and apoptosis.

Total glucosides of paeony (Paeonia lactiflora) alleviates blood-brain barrier disruption and cerebral ischemia/reperfusion injury in rats via suppressing inflammation and apoptosis

At present it remains uncertain as to whether total glucosides of paeony (TGP) are able to mediate neuroprotection in the context of cerebral ischemia/reperfusion (CIR) injury, and if so, what mechanisms underlie such protection. We employed a rat model of middle cerebral artery occlusion and reperfusion, and then Evans blue (EB), hematoxylin and eosin, Nissl staining, TUNEL staining, ELISAs and immunohistochemistry were used. We observed marked reductions in infarct volume, neurological deficits, and CIR-associated histopathological changes following TGP treatment. We further found that TGP was associated with restoration of the BBB integrity, a reduction in levels of cerebral IL-1β, IL-6 and TNF-α, and a decrease in overall neuronal apoptotic death that coincided with reduced Cleaved Caspase-3 and Bax expression, and elevated Bcl-2. These results demonstrate that TGP treatment is capable of reducing neurons damage and associated BBB dysfunction via anti-apoptotic and anti-inflammatory mechanisms in a rodent model of CIR injury.

Effects of velvet antler polypeptides on Alzheimer's disease cell model via miR-613 HDAC6 pathway

To study the effect of velvet antler polypeptides (VAP) on Alzheimer's disease (AD) cell model, Aβ_25-35 was used to induce SK-N-SH cells to obtain AD cell model. The MDA, SOD, GSH-Px levels were determined using relevant kits. Flow cytometry was conducted to detect apoptosis, Western blot was employed to measure Bcl-2, Bax, HDAC6 protein expression, and qPCR was used to assay microRNA (miR)-613 and HDAC6 mRNA levels. Target Scan prediction combined with dual luciferase reporting experiments was conducted to analyze the targeting relationship between miR-613 and HDAC6. miR-613 was transfected in SK-N-SH cells; Alternatively, anti-miR-613 was transfected, followed by Aβ_25-35 and 80 mg/L of VAP. The AD model cells showed increased MDA content, apoptosis rate, Bax protein expression, HDAC6 mRNA and protein expression, but lower SOD, GSH-Px activities, Bcl-2 protein level, and miR-613 expression (p<0.05). VAP reduced MDA content, apoptosis rate, Bax protein expression, HDAC6 mRNA and protein expression, but enhanced SOD, GSH-Px activities, Bcl-2 protein level, and miR-613 expression (p<0.05). Over-expression of miR-613 increased SOD, GSH-Px activities, and Bcl-2 protein expression in AD model cells, but reduced HDAC6 protein levels, MDA content, apoptosis rate, and Bax protein levels (p<0.05). VAP may regulate Aβ_25-35-induced apoptosis so as to treat Alzheimer's disease.

Isofraxidin: Synthesis, Biosynthesis, Isolation, Pharmacokinetic and Pharmacological Properties

Isofraxidin (7-hydroxy-6, 8-dimethoxy coumarin) (IF) is a hydroxy coumarin with several biological and pharmacological activities. The plant kingdom is of the most prominent sources of IF, which, among them, Eleutherococcus and Fraxinus are the well-known genera in which IF could be isolated/extracted from their species. Considering the complex pathophysiological mechanisms behind some diseases (e.g., cancer, neurodegenerative diseases, and heart diseases), introducing IF as a potent multi-target agent, which possesses several herbal sources and the multiple methods for isolation/purification/synthesis, along with the unique pharmacokinetic profile and low levels of side effects, could be of great importance. Accordingly, a comprehensive review was done without time limitations until February 2020. IF extraction methods include microwave, mechanochemical, and ultrasound, along with other conventional methods in the presence of semi-polar solvents such as ethyl acetate (EtOAc). In addition to the isolation methods, related synthesis protocols of IF is also of great importance. From the synthesis point of view, benzaldehyde derivatives are widely used as precursors for IF synthesis. Along with the methods of isolation and biosynthesis, IF pharmacokinetic studies showed hopeful in vivo results of its rapid absorption after oral uses, leading to different pharmacological effects. In this regard, IF targets varieties of inflammatory mediators including nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), tumor necrosis factor-α (TNF-α), and matrix metalloproteinases (MMPs). thereby indicating anticancer, cardioprotective, and neuroprotective effects. This is the first review on the synthesis, biosynthesis, isolation, and pharmacokinetic and pharmacological properties of IF in combating different diseases.

Novel dammarane-type saponins from Gynostemma pentaphyllum and their neuroprotective effect

Three novel dammarane-type saponins, 2α,3β,12β,20(S),24(S)-pentahydroxydammar-25-ene-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-20-O-β-D-glucopyranoside (1, namely gypenoside J1), 2α,3β,12β,20(S),25-pentahydroxydammar-23-ene-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-20-O-β-D-glucopyranoside (2, namely gypenoside J2) and 2α,3β,12β,20(S)-tetrahydroxydammar-25-en-24-one-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-20-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside (3, namely gypenoside J3) along with one known gypenoside (gypenoside LVII) were isolated from the aerial parts of G. pentaphyllum using various chromatographic methods. Their structures were elucidated on the basis of IR, 1D- (1H and 13C), 2D-NMR spectroscopy (HSQC, HMBC and COSY), and mass spectrometry (ESI-MS/MS). Their activity was tested using CCK-8 assay. These four compounds showed little anti-cancer activity with IC50 values more than 100 μM against four types of human cancer lines. The effects of them against H2O2-induced oxidative stress in human neuroblastoma SH-SY5Y cells were evaluated and they all showed potential neuroprotective effects with 3.64-18.16% higher cell viability than the H2O2-induced model group.

Bioactive chemical constituents from the seed testa of Vernicia fordii as potential neuroinflammatory inhibitors

Eight previously undescribed and 15 known components, including six neolignans, two monolignan, three sesquineolignans, three dineolignans, eight phenylpropanoids, and one steroid were identified from the seed testa of Vernicia fordii. Their structures were established based on the comprehensive analysis of NMR and ECD data. The anti-neuroinflammatory effects of the isolates were evaluated through nitrite assays in LPS-induced BV2 cells. As a result, isodiverniciasin A, diverniciasin B, diverniciasin C, isoprincepin, princepin, 3, 3'-bisdemethylpinoresinol, (+)-7-epi-sesamin-dicatechol, isoamericanin A, americanin B, 7S, 8R-americanin D, 4-hydroxyl cinnamic aldehyde, 3-hydroxyl-4-methoxyl cinnamic aldehyde and 24R-6β-hydroxy-24- ethylcholest-4-en-3-one exhibited significant inhibitory effects on nitric oxide (NO) production and isoprincepin, princepin, americanin B, and 4-hydroxyl cinnamic aldehyde suppressed the overexpression of inflammatory cytokines TNF-α, IL-1β, and IL-6 in over-activated microglia. The results suggested that bioactive ingredients from the seed testa of V. fordii can serve as potential therapeutic agents for neurodegenerative diseases.

Neuroprotective effect of Convolvulus pluricaulis Choisy in oxidative stress model of cerebral ischemia reperfusion injury and assessment of MAP2 in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Convolvulus pluricaulis Choisy commonly known as Shankhapushpi, is traditionally prescribed for nerve debility, loss of memory, epilepsy and as nervine tonic. Plant also proved to have diverse pharmacological activity but the neuroprotection in ischemic stroke were not found.

AIM OF THE STUDY

To investigate the effect of Convolvulus pluricaulis against bilateral common carotid artery (BCCA) occlusion induced cerebral ischemic reperfusion injury.

MATERIALS AND METHODS

The neuroprotective activity of Convolvulus pluricaulis against bilateral common carotid artery (BCCA) occlusion induced cerebral ischemic reperfusion (I/S) injury. Sprague-Dawley rats of either sex (200-250 g) were divided into nine groups of 8 rats each. Sham and control group, saline treated 10 ml/kg orally. Third group treated with Quercetin 25 mg/kg orally and fourth to ninth groups treated with chloroform and ethanol extract of Convolvulus pluricaulis 100, 200, and 400 mg/kg (p.o.) respectively. Control, Quercetin and extract treated groups underwent 30 min BCCA occlusion and 24 h reperfusion on 10th day but sham underwent same surgery without BCCA occlusion and 24 h reperfusion on 10th day. The antioxidant enzymatic and non-enzymatic levels were estimated by UV spectroscopic method and cerebral infarction area, Blood brain barrier disruption, microtubule-associated protein 2 immunohistochemical and histopathological studies were carried out.

RESULTS

The results of the study indicate that the chloroform and ethanol extract of Convolvulus pluricaulis showed neuroprotective activity by a significant decrease in lipid peroxidation (p < 0.001) and an increase in superoxide dismutase (p < 0.01, p < 0.001), catalase (p < 0.01, p < 0.001), glutathione (p < 0.001), and total thiol (p < 0.001) levels in extract-treated groups as compared to control group. Measurement of cerebral infarction area, blood brain barrier disruption, microtubule-associated protein 2 immunohistochemical and histopathological studies further supported the protective effect of the extract.

CONCLUSIONS

Present study revile that Convolvulus pluricaulis has potent neuroprotection against bilateral common carotid artery (BCCA) occlusion induced cerebral ischemic reperfusion injury.

Aglaia odorata Lour. extract inhibit ischemic neuronal injury potentially via suppressing p53/Puma-mediated mitochondrial apoptosis pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Aglaia odorata Lour. is a traditional Chinese medicinal plant possessing properties of improving blood circulation, and it is widely used in the treatment of dizziness, traumatic injuries and bruises.

AIM OF STUDY

In this study, we are aimed to investigate the cerebral protection effect of the extracts from leaves of Aglaia odorata Lour. (ELA) and the potential mechanism in vivo and in vitro.

MATERIALS AND METHODS

The therapeutic effect of ELA on ischemic cerebral stroke was measured on a middle cerebral artery occlusion (MCAO) rat model. Protective effect of ELA on oxygen-glucose deprivation/reperfusion (OGD/R)-induced PC12 cells was measured by MTT assay. The apoptotic cells were observed by Hoechst 33258 staining and acridine orange/ethidium bromide double staining assay. Mitochondria were observed by Mitotracker staining assay. The mitochondrial membrane potential was determined by JC-1 staining assay. Western blot was used to investigate the effects of ELA on apoptosis-related proteins.

RESULTS

We showed that ELA was an effective neuroprotective agent. In vivo experiments, ELA exerted significant protective effect on MCAO model. TTC staining showed that ELA could reduce cerebral infarction area against MCAO insult. HE and Nissl's staining indicated that ELA could reverse the damage of cortex and hippocampus caused by MCAO. In vitro experiments, ELA showed significant protective effect on OGD/R-induced PC12 cells by reducing the number of apoptotic cells, increasing mitochondrial membrane potential, and reducing superoxide aggregation, further suppressing mitochondrial caspase-9/3 apoptosis pathway. Moreover, protective effect of ELA on mitochondrial function may be exerted by inhibiting p53/Puma signal pathway.

CONCLUSION

Our results suggest that ELA exerts a marked neuroprotective effect against cerebral ischemia potentially via suppressing p53/Puma-mediated mitochondrial caspase-9/3 apoptosis pathway.

Health Properties and Composition of Honeysuckle Berry Lonicera caerulea L. An Update on Recent Studies

Lonicera caerulea L., also known as haskap or honeysuckle berry, is a fruit commonly planted in eastern Europe, Canada and Asia. The fruit was registered as a traditional food from a third country under European Union regulations only on December 2018. It is resistant to cold, pests, various soil acidities and diseases. However, its attractiveness is associated mostly with its health properties. The fruit shows anticancer, anti-inflammatory, and antioxidant activity-important factors in improving health. These features result from the diverse content of phytochemicals in honeysuckle berries with high concentrations of phytocompounds, mainly hydroxycinnamic acids, hydroxybenzoic acids, flavanols, flavones, isoflavones, flavonols, flavanones and anthocyanins but also iridoids, present in the fruit in exceptional amounts. The content and health properties of the fruit were identified to be dependent on cultivar, genotype and the place of harvesting. Great potential benefits of this nutritious food are its ability to minimize the negative effects of UV radiation, diabetes mellitus and neurodegenerative diseases, and to exert hepato- and cardioprotective activity.

The asarone-derived phenylpropanoids from the rhizome of Acorus calamus var. angustatus Besser

Phenylpropanoids comprise a broad spectrum of biologically active natural products. As part of our ongoing research on antiepileptic active compounds from traditional Chinese herb, Acorus calamus var. angustatus Besser, three undescribed phenylpropanoids and twenty-two known ones were isolated. All the undescribed structures were determined by a combination of 1D and 2D NMR, HRMS. In addition, γ-asaronol was identified as racemates and its absolute configuration were determined by the modified Mosher's method and ECD spectral data. Furthermore, some selected isolated compounds were evaluated for their cell viability and neuroprotective activities in H₂O₂-induced SH-SY5Y cells. α-Asaronol, β-asaronol, 3-(2,4,5-trimethoxyphenyl)propan-1-ol and 1,2,4-trimethoxy-5-(3-methoxypropyl)benzene exerted potential protective activity from neuronal oxidative stress in all test concentrations ranging from 0.01 to 100 μM, in which the neuroprotective activity of β-asaronol was the best.

Sarsasapogenin: A steroidal saponin from Asparagus racemosus as multi target directed ligand in Alzheimer's disease

Alzheimer's disease (AD) is multi-factorial disorder characterized by impaired memory and cognition deficit. AD is characterized by impaired cholinergic transmission, extracellular amyloid beta deposits, neurofibrillary tangles and oxidative stress. A multi-target directed ligand (MTDL) approach is required to devise a therapeutic strategy against AD. In the present study, Asparagus racemosus aqueous extract was chosen, as it possess abundant medicinal properties including nootropic effect mentioned in ancient Ayurvedic texts. Moreover, its secondary metabolite sarsasapogenin (SRS) was also selected for this multi-target study for the very first time. The current study demonstrated that sarsasapogenin significantly inhibits key enzymes involved in pathogenesis of AD which are acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), BACE1 and MAO-B in a concentration dependent manner. SRS also exhibited anti-amyloidogenic, anti-oxidant and neuroprotective effects by in vitro studies. The IC₅₀ values of SRS is 9.9 μM and 5.4 μM for AChE and BuChE respectively. SRS also significantly inhibited Aβ42 fibrillization up to 68% at 40 μM concentration as compared to control. TEM visualization showed Aβ aggregates as short and scattered fibril clearly indicating SRS significantly inhibited peptide nucleation and fibril formation. Furthermore, the SRS was found to exert neuroprotective effect on PC12 cells against Aβ42 and H₂O₂-mediated cytotoxicity. The cell survival was 62% and 69% against Aβ42 and H₂O₂-mediated cytotoxicity, respectively. SRS also inhibited monoaminoxidase-B (MAO-B) and BACE1 enzymes in concentration dependent manner. Molecular docking studies indicated that SRS binds to the catalytic sites of multiple targets (AChE, BuChE, Aβ42, BACE1, and MAO-B) in a significant manner that might having disease-modifying effects. Thus SRS is acting as suitable lead and can be utilised as MTDL compound for factors implicated in AD.

Neuroprotective Effect of CR-777, a Glutathione Derivative of Withaferin A, Obtained through the Bioconversion of Withania somnifera (L.) Dunal Extract by the Fungus Beauveria bassiana

The bioconversion of Withania somnifera extract by the fungus Beauveria bassiana leads to cysteine and glutathione derivatives of withaferin A at the C-6 position. The compounds were purified and fully characterized by 1D-NMR, 2D-NMR, and HRMS analysis. The glutathione derivative CR-777 was evaluated as a neuroprotective agent from damage caused by different neurotoxins mimicking molecular symptoms in Parkinson´s disease (PD), including 1-methyl-4-phenylpyridinium (MPP+), 6-hydroxydopamine (6-OHDA), and α-synuclein (α-Syn). CR-777, at nanomolar concentrations, protected dopaminergic and cortical neurons. In 6-OHDA-treated neurons, CR-777 increased cell survival and neurite network and decreased the expression of α-Syn. Using specific inhibitors of cell toxicity signaling pathways and specific staining experiments, the observed role of CR-777 seemed to involve the PI3K/mTOR pathway. CR-777 could be considered as a protective agent against a large panel of neuronal stressors and was engaged in further therapeutic development steps.

Phytotherapy in treatment of Parkinson's disease: a review

Context: Parkinson's disease (PD) is a neurodegenerative disorder due to gradual loss of dopaminergic nerves in the substantia nigra (SN) in the midbrain. PD leads to certain motor disorders including resting tremor, muscle stiffness and slow movement. Medicinal plants have shown positive pharmacological effects in treating different models of PD. Objective: Tendency to use natural products, especially plants, for the treatment of PD has been growing. This article reviews the basic aspects of medicinal plants and their bioactive compounds that could be used to treat PD. Methods: Reliable articles indexed in databases ISI, SID, PubMed, PubMed Central, Scopus and Web of Science were used. A total of 12 plant-derived active ingredients and 18 herbal extracts were included. Different compounds have so far been isolated from plants that affect PD especially by targeting pathways associated with the pathogenesis of the disease. Results: Although some herbal extracts such as Hibiscus asper Hook. f. (Malvaceae), Ginkgo biloba L. (Ginkgoaceae), Carthamus tinctorius L (Asteraceae) and certain active ingredients, such as berberine and curcumin, have shown positive effects in animal models of PD, potential active ingredients and mechanisms of action should be investigated in additional studies. Discussion and conclusions: Despite the wide variety of plants in the world, a limited number of them have been studied for anti-Parkinsonian activity, and therefore, there are numerous perspectives in this field for future studies on plants and their bioactive compounds.

Evaluation of the neuroprotective and antioxidant effects of Dorema aucheri extract on cerebral ischaemia-reperfusion injury in rats

CONTEXT

The hydroalcoholic extract of Dorema aucheri Bilhar (Umbelliferae) (DA) leaves, a medicinal plant, has powerful antioxidant properties.

OBJECTIVE

This study evaluates the neuroprotective effects of pre-treatment with DA leaves extract against cerebral ischaemia-induced brain injury through alteration of the antioxidant capacity.

MATERIALS AND METHODS

The study was conducted in three groups of Wistar rats (N = 47) as follows; sham, control ischaemic and pre-treated ischaemic groups. Rats were administered a fresh hydroalcoholic extract of DA leaves at a dosage of 200 mg/kg/day for 14 days. Then, the middle cerebral artery (MCA) of the right hemisphere was occluded for 90 min to achieve cerebral ischaemia. After 24 h reperfusion, cerebral infarction and superoxide dismutase (SOD) and catalase activities, as well as malondialdehyde (MDA), glutathione, and NOx contents were determined in the right hemispheres.

RESULTS

Occlusion of the right MCA caused noticeable cerebral infarction (298 ± 21 mm³) in control ischaemic group, but pre-treatment with DA extract considerably attenuated it (92 ± 14 mm³) in the pre-treated ischaemic group. DA extract significantly decreased the levels of MDA by 28% and NOx by 11% in pre-treated ischaemic group compared to the control ischaemic group. DA extract also enhanced glutathione content by 7%, SOD activity by 16% and catalase activity by 46% in pre-treated ischaemic rats compared to control ischaemic rats.

DISCUSSION AND CONCLUSIONS

DA is able to improve the antioxidant capacity and injuries of ischaemic brain. It is proposed as a neuroprotectant following cerebral ischaemia to decrease the injuries of ischaemic stroke.

Lotus seedpod proanthocyanidins protect against neurotoxicity after methyl-mercuric chloride injury

In the present study, to investigate the prevention mechanism of proanthocyanidins from lotus seedpod (LSPCs) on methyl mercuric chloride (MMC) induced neurotoxicity, neuron/astrocyte cells were co-cultured to simulate the microenvironment in vivo to the greatest extent. The results showed that, compared with MMC group, pretreatment with LSPCs not only improved cell survival rate, decreased the release of lactate dehydrogenase (LDH), decreased the intracellular reactive oxygen species (ROS) level, and prevented the increase of intracellular [Ca²⁺]i, but also significantly increased the total anti-oxidation capacity (T-AOC) (p＜0.05), the levels of glutathione peroxidase (GSH-Px) (p＜0.05), glutathione (GSH) (p＜0.05), and mitochondrial membrane potential (MMP) (p＜0.01). Besides, LSPCs up-regulated the expression of transcriptional factor Nrf2/HO-1 in a concentration-dependent manner. Moreover, LSPCs reduced the expression of Bax protein, significantly increased the expression of Bcl-xl, Bcl-2, β-Ⅲ-Tubulin, SYN, and Arc proteins. The expression of these proteins is mainly regulated by genes and reflects the changes of genes functions. Taken together, these results suggested that LSPCs could enhance cellular antioxidant defense capacity through regulating the activation of Nrf2/HO-1, and involving the inhibition of mitochondria-mediated apoptotic signaling pathway.

Alkaloid Enantiomers from Isatis tinctoria with Neuroprotective Effects against H2O2-Induced SH-SY5Y Cell Injury

Six pairs of alkaloid enantiomers including 11 new alkaloids (1A: /1B: -5A: /5B, 6A: ) were isolated from the leaves of Isatis tinctoria. Their structures were established by extensive spectroscopic analyses. Enantiomers were separated successfully by chiral chromatographic column and the absolute configurations of all isolates were determined by comparison of experimental and calculated electronic circular dichroism spectra. The isolated alkaloids were evaluated for their neuroprotective activities against H₂O₂-induced cell injury in human neuroblastoma SH-SY5Y cells. The results showed that 5A/5B: and 6A/6B: exhibited potent neuroprotective activities at 50 µM compared with the H₂O₂-treated group.

Pistacia Genus as a Potential Source of Neuroprotective Natural Products

Neuroprotective agents are able to defend the central nervous system against acute or chronic neuronal injuries. Even with the progress made over the last decades, most of the medications prescribed for the management of neurodegenerative diseases can only reduce their symptoms and slow down their progression. Based on natural product research, there are potential effective medicinal plants and phytochemicals for modulating neuronal functions and protecting against neurodegeneration. Plants in the genus Pistacia are also among valuable natural resources for neuroprotection research based on experiences in traditional medicine. Studies have supported the value of bioactive compounds of the genus Pistacia for central nervous system disorders such as Alzheimer's, Parkinson's, multiple sclerosis, cerebral ischemia, depression, and anxiety. Related literature has also revealed that most of the evidence on neuroprotection in the genus Pistacia is in the form of preliminary studies, mainly including models of behavior, motor function, and memory impairments in animals, neural toxicity, cerebral ischemia and seizure models, evaluation of their effects on antioxidant and inflammatory biomarkers, amyloid β aggregation, and acetylcholinesterase as well as investigations into some cellular pathways. Along with the phytonutrients in kernels such as pistachios, various phytochemicals, mostly terpenes, and phenolic compounds have also been identified in different plant parts, in particular their oleoresins, of species in the genus Pistacia. In this review, the pharmacology of neurological effects and related molecular mechanisms of the plants belonging to the genus Pistacia and its active constituents, as well as pharmacokinetics aspects, are discussed.

Benefits of curcumin in brain disorders

Curcumin is widely consumed in Asia either as turmeric directly or as one of the culinary ingredients in food recipes. The benefits of curcumin in different organ systems have been reported extensively in several neurological diseases and cancer. Curcumin has got its global recognition because of its strong antioxidant, anti-inflammatory, anti-cancer, and antimicrobial activities. Additionally, it is used in diabetes and arthritis as well as in hepatic, renal, and cardiovascular diseases. Recently, there is growing attention on usage of curcumin to prevent or delay the onset of neurodegenerative diseases. This review summarizes available data from several recent studies on curcumin in various neurological diseases such as Alzheimer's disease, Parkinson's disease, Multiple Sclerosis, Huntington's disease, Prions disease, stroke, Down's syndrome, autism, Amyotrophic lateral sclerosis, anxiety, depression, and aging. Recent advancements toward increasing the therapeutic efficacy of curcuma/curcumin formulation and the novel delivery strategies employed to overcome its minimal bioavailability and toxicity studies have also been discussed. This review also summarizes the ongoing clinical trials on curcumin for different neurodegenerative diseases and patent details of curcuma/curcumin in India.

Amaryllidaceae alkaloids from Narcissus pseudonarcissus L. cv. Dutch Master as potential drugs in treatment of Alzheimer's disease

Twenty-one known Amaryllidaceae alkaloids of various structural types and one undescribed alkaloid, named narcimatuline, have been isolated from fresh bulbs of Narcissus pseudonarcissus L. cv. Dutch Master. The chemical structures were elucidated by combination of MS, HRMS, 1D and 2D NMR spectroscopic techniques, and by comparison with literature data. Narcimatuline amalgamates two basic scaffolds of Amaryllidaceae alkaloids in its core, namely galanthamine and galanthindole. All isolated compounds were evaluated for their in vitro acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), prolyl oligopeptidase (POP), and glycogen synthase kinase-3β (GSK-3β) inhibitory activities. The most interesting biological profile was demonstrated by newly isolated alkaloid narcimatuline.

Phenolic constituents with neuroprotective activities from Hypericum wightianum

Five undescribed phenolic compounds, inclusing a depsidone derivative, hyperwightin A, a flavone derivative, hyperwightin B, and three benzophenone glycosides, hyperwightins C-E, along with four known ones were isolated from the 95% EtOH extract of the whole plants of Hypericum wightianum. Structures of the obtained compounds were elucidated by spectroscopic analyses. The protective effects of the isolates against corticosterone-induced PC12 cell injury were assessed. Hyperwightin E, petiolin G and hyperxanthone exhibited noticeable neuroprotection at 10 μM.

A Comprehensive Review on Chemical and Pharmacological Potential of Viola betonicifolia: A Plant with Multiple Benefits

Viola betonicifolia (Violaceae) is commonly recognized as “Banafsha” and widely distributed throughout the globe. This plant is of great interest because of its traditional, pharmacological uses. This review mainly emphases on morphology, nutritional composition, and several therapeutic uses, along with pharmacological properties of different parts of this multipurpose plant. Different vegetative parts of this plant (roots, leaves, petioles, and flowers) contained a good profile of essential micro- and macronutrients and are rich source of fat, protein, carbohydrates, and vitamin C. The plant is well known for its pharmacological properties, e.g., antioxidant, antihelminthic, antidepressant, anti-inflammatory, analgesic, and has been reported in the treatment of various neurological diseases. This plant is of high economic value. The plant has potential role in cosmetic industry. This review suggests that V. betonicifolia is a promising source of pharmaceutical agents. This plant is also of significance as ornamental plant, however further studies needed to explore its phytoconstituents and their pharmacological potential. Furthermore, clinical studies are needed to use this plant for benefits of human beings.

Hyperforatins L-U: Prenylated acylphloroglucinols with a terminal double bond from Hypericum perforatum L. (St John's Wort)

Hyperforatins L-U, ten undescribed polycyclic polyprenylated acylphloroglucinols (PPAPs) bearing a terminal double bond, together with a known compound hypericumoxide J, were isolated from the aerial parts of Hypericum perforatum L. Their structures were elucidated by spectroscopic methods, including HRESIMS, IR, UV, and NMR (¹H, ¹³C, DEPT, HSQC, HMBC, ¹H-¹H COSY, and NOESY experiments). Their absolute configurations were determined by comprehensive analyses of their experimental ECD spectra in conjunction with a modified Mosher's method. Evaluation of their neuroprotective activities highlighted hyperforatin L, which displayed mild activity at a concentration of 10 μM.

Citrus flavonoid 3,5,6,7,8,3',4'-heptamethoxyflavone induces BDNF via cAMP/ERK/CREB signaling and reduces phosphodiesterase activity in C6 cells

BACKGROUND

Brain-derived neurotrophic factor (BDNF) is associated with onset of several central nervous system disorders, e.g., Parkinson's disease, Alzheimer's disease, depression, epilepsy, and chronic pain. In our previous in vivo studies using ischemic and depression mouse models, we revealed that citrus flavonoid 3,5,6,7,8,3',4'-heptamethoxyflavone (HMF) exerts neuroprotective effects by enhancing the expression of BDNF in astrocytes within the hippocampus. Therefore, in the present study, we examined the mechanism of BDNF induction by HMF in vitro using rat C6 glioma cells.

METHODS

C6 glioma cells were treated with HMF (10 μM) or HMF + U0126 (10 μM), HMF + H89 (1 μM), or HMF + K252a (200 nM) for 48 h. The protein level of mature BDNF (m-BDNF), phosphorylated-ERK (p-ERK) and phosphorylated-cAMP-response element binding protein (p-CREB) were measured using western blot analysis. To clarify the mechanism of HMF for increasing m-BDNF, the inhibitory effect of phosphodiesterase 4B (PDE4B) and PDE4D, and intracellular cAMP levels were examined by ELISA.

RESULTS

Our findings revealed that the m-BDNF-inducing activity of HMF was abolished by U0126 but not by H89 or K252a. HMF was found to phosphorylate (activate) ERK and cAMP-response element binding protein (CREB), a BDNF transcription factor. HMF inhibited PDE4B and PDE4D activity. Moreover, 10 μM HMF elevated intracellular cAMP levels in C6 cells.

CONCLUSIONS

These findings suggest that HMF might exert its neuroprotective effects by inducing m-BDNF expression in C6 cells, model cell line of astrocytes, via the activation of cAMP/ERK/CREB signaling and inhibiting PDE4B or PDE4D.

Isolation of enantiomeric furolactones and furofurans from Rubus idaeus L. with neuroprotective activities

A phytochemical study on the fruits of Rubus idaeus L. (Rosaceae) yielded eight pairs of enantiomeric lignans, including one undescribed furolactone named (-)-idaeusinol A and six undescribed furofuran derivatives named (+/-)-idaeusinol B-D. The structures of these isolated compounds were elucidated by spectroscopic analyses and a combination of computational techniques including gauge-independent atomic orbital (GIAO) calculation of 1D NMR data and TD-DFT calculation of electronic circular dichroism (ECD) spectra. Bioactivity screenings suggested that (+)-idaeusinol D exhibited the most significant protective effect against H₂O₂-induced neurotoxicity at the concentration of 25 μM. In contrast, (-)-idaeusinol D, as the enantiomer of (+)-idaeusinol D, showed no effect against H₂O₂-induced neurotoxicity at both 25 and 50 μM concentration.