Curcumin and Health

Nowadays, there are some molecules that have shown over the years a high capacity to act against relevant pathologies such as cardiovascular disease, neurodegenerative disorders or cancer. This article provides a brief review about the origin, bioavailability and new research on curcumin and synthetized derivatives. It examines the beneficial effects on health, delving into aspects such as cancer, cardiovascular effects, metabolic syndrome, antioxidant capacity, anti-inflammatory properties, and neurological, liver and respiratory disorders. Thanks to all these activities, curcumin is positioned as an interesting nutraceutical. This is the reason why it has been subjected to several modifications in its structure and administration form that have permitted an increase in bioavailability and effectiveness against different diseases, decreasing the mortality and morbidity associated to these pathologies.

[BRAIN FOCAL ISCHEMIA-REPERFUSION CAUSES A DECREASED RESISTANCE OF ERYTHROCYTES FROM VENOUS BLOOD TO ACID HEMOLYSIS, WHICH IS PREVENTED BY ECDYSTERONE]

We investigated the resistance of erythrocytes from rat brain venous blood to acid hemolysis in the dynamics of brain ischemic period (15, 30, 45 and 60 min), as well as in the early (5 min) and distant (24h) period of brain reperfusion. Brain ischemia-reperfusion was made in rats that received ecdysterone (standartized extract of Serratula coronata) within 18 days (per os, 1 mg/kg). Analysis of the kinetic curves of acid hemolysis showed a pronounced (60 times, from 1.45 to 85.85% at 60 min of brain ischemia and at 5 min of brain reperfusion, respectively) increase of unstable erythrocytes that hemolyzed easily (< 2.5 min). In the preconditioned rats, this increase was only 8-fold. During the period of brain ischemia, with a maximum at 15th minute, in the venous blood from brain the diene conjugates (DK) pools increased from 2.40 to 9.48 ng/mg protein and LTC4 pools increased from 1.49 to 5.98 pmol/mg protein. Even more pools of DC and LTC4 were increased at 5th min of brain reperfusion. In animals received ecdysterone, during ischemia and early reperfusion period, both pools of DC and LTC4 in venous blood were lower than that in the controls. The latter implies a possible antiradical mechanism of the protective effect of ecdysterone.

Mitochondria Related Pathway Is Essential for Polysaccharides Purified from Sparassis crispa Mediated Neuro-Protection against Glutamate-Induced Toxicity in Differentiated PC12 Cells

The present study aims to explore the neuro-protective effects of purified Sparassis crispa polysaccharides against l-glutamic acid (l-Glu)-induced differentiated PC12 (DPC12) cell damages and its underlying mechanisms. The Sparassis crispa water extract was purified by a DEAE-52 cellulose anion exchange column and a Sepharose G-100 column. A fraction with a molecular weight of 75 kDa and a diameter of 88.9 nm, entitled SCWEA, was obtained. SCWEA was identified with a triple helix with (1→3)-linked Rha in the backbone, and (1→2) linkages and (1→6) linkages in the side bone. Our results indicated that the pre-treatment of DPC12 cells with SCWEA prior to l-Glu exposure effectively reversed the reduction on cell viability (by 3-(4,5-cimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay) and reduced l-Glu-induced apoptosis (by Hoechst staining). SCWEA decreased the accumulation of intracellular reactive oxygen species, blocked Ca²⁺ influx and prevented depolarization of the mitochondrial membrane potential in DPC12 cells. Furthermore, SCWEA normalized expression of anti-apoptotic proteins in l-Glu-explored DPC12 cells. These results suggested that SCWEA protects against l-Glu-induced neuronal apoptosis in DPC12 cells and may be a promising candidate for treatment against neurodegenerative disease.

Cassane Diterpenoids from the Pericarps of Caesalpinia bonduc

Ten new cassane-type diterpenoids, caesalbonducins D-F (1-3), 6-deacetoxybonducellpin B (4), 3-acetoxy-α-caesalpin (5), 2(3)-en-α-caesalpin (6), 1α-hydroxycaesalpinin J (7), 1α-hydroxy-6-decaetoxysalpinin J (8), 6α-hydroxycaesall M (9), and 6α-hydroxy-14(17)-dehydrocaesalpin F (10), along with eight known compounds (11-18), were isolated from the pericarps of Caesalpinia bonduc. Compounds 1-3 and 11 are methyl-migrated cassane-type diterpenoids with a 19(4→3)-cassane skeleton. The structures of 1-10 were elucidated on the basis of 1D and 2D NMR methods and other spectroscopic analysis. The neuroprotective effects of the isolated compounds were evaluated.

[PHYTOSAPONINS OF DIOSCOREA: PROSPECTS FOR APPLICATION IN WOMEN]

This literature review is focused on findings concerning the pharmacological effects of Dioscorea phytosaponins (DPSs) on female organism. Expediency and prospects of developing DPS preparations for the treatment of mnestic and metabolic disorders accompanying climacteric syndrome are assessed.

Neuroprotective and antioxidant lanostanoid triterpenes from the fruiting bodies of Ganoderma atrum

Five new lanostanoid triterpenes were isolated from the ethanol extract of the fruiting bodies of Ganoderma atrum. The structures of the isolated compounds were established based on 1D and 2D ((1)H-(1)H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated compounds were tested in vitro for neuroprotective activities against 6-OHDA-induced cell death in SH-SY5Y cells and radical scavenging activities. As a result, compounds 2 and 5 exhibited potent neuroprotective activity against 6-OHDA-induced cell death in SH-SY5Y cells with the lowest IC50 value (0.5 μM) while compounds 1, 3 and 4 possessed significant neuroprotective activity with IC50 value less than 10 μM. Additionally, all tested compounds 1-6 showed the comparable free radical scavenging activities with the standard drug trolox in both ABTS (+) and DPPH experiment.

Chemical constituents from the roots and stems of Litsea cubeba

A new monoterpene and a new lignan, named litsecols A and B (1 and 2), respectively, together with nine known compounds (3-11), were isolated in a continuous investigation on the roots and stems of Litsea cubeba. Their structures were elucidated on the basis of extensive spectroscopic data analysis, and the absolute configuration of 1 was resolved by X-ray diffraction analysis. Compounds 2-5 and 7-9 showed significant inhibitory activity against nitric oxide (NO) production in lipopolysaccharide (LPS)-induced murine microglial (Bv-2) cell line. Compounds 10 and 11 exhibited significant neuroprotective effect against hydrogen peroxide-induced oxidative damage in rat adrenal pheochromocytoma (PC12) cell line.

Withania somnifera Improves Ischemic Stroke Outcomes by Attenuating PARP1-AIF-Mediated Caspase-Independent Apoptosis

Withania somnifera (WS), popularly known as "Ashwagandha" has been used for centuries as a nerve tonic. Its protective effect has been elucidated in many neurodegenerative pathologies, although there is a paucity of data regarding its effects in ischemic stroke. We examined the neuroprotective properties of an aqueous extract of WS in both pre- and poststroke treatment regimens in a mouse model of permanent distal middle cerebral artery occlusion (pMCAO). WS (200 mg/kg) improved functional recovery and significantly reduced the infarct volume in mice, when compared to those treated with vehicle, in both paradigms. We investigated the protective mechanism/s induced by WS using brain cortices by testing its ability to modulate the expression of key proteins in the ischemic-apoptotic cascade. The Western blots and immunofluorescence analyses of mice cortices revealed that WS upregulated the expression of hemeoxygenase 1 (HO1) and attenuated the expression of the proapoptotic protein poly (ADP-ribose) polymerase-1 (PARP1) via the PARP1-AIF pathway, thus preventing the nuclear translocation of apoptosis-inducing factor (AIF), and subsequent apoptosis. Semaphorin-3A (Sema3A) expression was reduced in WS-treated group, whereas Wnt, pGSK3β, and pCRMP2 expression levels were virtually unaltered. These results indicate the interplay of antioxidant-antiapoptic pathways and the possible involvement of angiogenesis in the protective mechanism of WS while emphasizing the noninvolvement of one of the prime pathways of neurogenesis. Our results suggest that WS could be a potential prophylactic as well as a therapeutic agent aiding stroke repair, and that part of its mechanism could be attributed to its antiapoptotic and antioxidant properties.

Spiroindole Alkaloids and Spiroditerpenoids from Aspergillus duricaulis and Their Potential Neuroprotective Effects

Six new spiroindole alkaloids (1-6) and two new spiroditerpenoids (7 and 8) were isolated from an EtOAc extract of Aspergillus duricaulis culture media together with five known compounds. The structures of the isolated compounds were elucidated by analysis of NMR and MS data, and the absolute configurations of compounds 1-8 were confirmed by CD spectroscopic methods. All isolated compounds were evaluated for their inhibition of beta-amyloid (Aβ) aggregate-induced toxicity in PC12 cells and Aβ aggregation. Compounds 8-11 efficiently protected PC12 cells against Aβ aggregate-induced toxicity, but only compound 9 inhibited Aβ aggregation. On the other hand, compounds 4 and 5 exhibited moderate inhibitory effects on Aβ aggregation, but did not protect the cells from Aβ aggregate-induced toxicity. Preincubating Aβ monomers with compounds 4 and 5 rescued PC12 cells against Aβ aggregate-induced toxicity by reducing neurotoxic Aβ aggregates. Compound 9 inhibited both Aβ aggregate-induced toxicity and Aβ aggregation.

γ- and δ-Lactams from the Leaves of Clausena lansium

Eight new clausenamides, including three γ-lactams (1-3), four δ-lactams (4-7), and an amide (8), and seven known lactams, including compounds 9-11, which were purified from natural sources for the first time, were characterized from the leaves of Clausena lansium. Their structures were elucidated using spectroscopic methods, and the absolute configurations were determined using electronic circular dichroism and single-crystal X-ray diffraction analyses with Cu Kα radiation. Compound 2 (50 μM) protected 22.24% of cortical neurons against Aβ25-35-induced cell death.

Forsythoneosides A-D, Neuroprotective Phenethanoid and Flavone Glycoside Heterodimers from the Fruits of Forsythia suspensa

Forsythoneosides A-D (1-4), four unusual adducts of a flavonoid unit fused to a phenylethanoid glycoside through a pyran ring or carbon-carbon bond, and four new phenylethanoid glycosides (5-8) were isolated from the fruits of Forsythia suspensa, together with nine known compounds. The structures of 1-8, including their absolute configurations, were elucidated by spectroscopic data as well as experimental and calculated electronic circular dichroism analysis. Compounds 2 and 4 inhibited PC12 cell damage induced by rotenone, and increased cell viability from 53.9 ± 7.1% to 70.1 ± 4.0% and 67.9 ± 5.2% at 0.1 μM, respectively.

Natural β-Dihydroagarofuran-Type Sesquiterpenoids as Cognition-Enhancing and Neuroprotective Agents from Medicinal Plants of the Genus Celastrus

Alzheimer's disease (AD) is an irreversible, multifaceted, and progressive neurodegenerative disorder. Over the past 30 years, the search for anti-AD drugs has been primarily based on the cholinergic deficiency hypothesis and/or the β-amyloid (Aβ) cascade hypothesis. In this study, we report the identification of 16 new and 38 known β-dihydroagarofuran-type sesquiterpenoids from Celastrus flagellaris and Celastrus angulatus. The β-dihydroagarofuran-type sesquiterpenoids 58, 59, 61, and 63 significantly attenuated scopolamine-induced prolonged escape latency and increased number of errors compared with the control group. At 10 μM, 21 of the 62 tested β-dihydroagarofuran-type sesquiterpenoids rescued Aβ25-35-induced SH-SY5Y cells from viability reduction, which increased the cell viability from 64.6% for the model to more than 74.0%. The majority of the β-dihydroagarofuran-type sesquiterpenoids with ester groups exhibited stronger activity than those with free hydroxy groups or without substituents at the same positions. These results identified a new chemical skeleton as drug lead for the investigation of novel therapeutic agents against AD.

3,5-Diarylpyrazole Derivatives Obtained by Ammonolysis of the Total Flavonoids from Chrysanthemum indicum Extract Show Potential for the Treatment of Alzheimer's Disease

Four new 3,5-diarylpyrazole analogues (1-4) were isolated from an extract of the flowers of Chrysanthemun indicum using a combination of ammonolysis of the total flavonoid extract and an Aβ aggregation inhibitory activity guided purification procedure. All four compounds (1-4) showed moderate to potent activity against Aβ aggregation with EC50 values of 4.3, 15.8, 1.3, and 2.9 μM, respectively. Moreover, compound 3 showed low cytotoxicity and significant neuroprotective activity against Aβ-induced cytotoxicity in the SH-SY5Y cell line. This report is the first to show that 3,5-diarylpyrazole analogues can inhibit Aβ aggregation and exhibit neuroprotective activity with potential for the treatment of Alzheimer's disease. Taken together, the method presented here offers an alternative approach to yield bioactive compounds.

Schisantherin A protects against 6-OHDA-induced dopaminergic neuron damage in zebrafish and cytotoxicity in SH-SY5Y cells through the ROS/NO and AKT/GSK3β pathways

ETHNOPHARMACOLOGICAL RELEVANCE

The fruit of Schisandra chinensis (Turcz.) Baill, has been traditionally used in management of liver diseases and ageing associated neurodegeneration. The bioactive compound from this medicinal plant would be valuable for its potential use in prevention and treatment of Parkinson׳s disease.

AIM OF THE STUDY

The overall objective of the present study was to understand the neuroprotective effect of schisantherin A, a dibenzocyclooctadiene lignan from the fruit of S. chinensis (Turcz.) Baill, and to elucidate its underlying mechanism of action.

MATERIAL AND METHODS

This study investigated the protective effect of schisantherin A against selective dopaminergic neurotoxin 6-hydroxydopamine (6-OHDA)-induced neural damage in human neuroblastoma SH-SY5Y cells and zebrafish models. Oxidative stress and related signaling pathways underlying the neuroprotective effect were determined by multiple biochemical assays and Western blot.

RESULTS

Pretreatment with schisantherin A offered neuroprotection against 6-OHDA-induced SH-SY5Y cytotoxicity. Moreover, schisantherin A could prevent 6-OHDA-stimulated dopaminergic neuron loss in zebrafish. Our mechanistic study showed that schisantherin A can regulate intracellular ROS accumulation, and inhibit NO overproduction by down-regulating the over-expression of iNOS in 6-OHDA treated SH-SY5Y cells. Schisantherin A also protects against 6-OHDA-mediated activation of MAPKs, PI3K/Akt and GSK3β.

CONCLUSION

These findings demonstrate that schisantherin A may have potential therapeutic value for neurodegenerative diseases associated with abnormal oxidative stress such as Parkinson׳s disease.

Acerogenin A from Acer nikoense Maxim Prevents Oxidative Stress-Induced Neuronal Cell Death through Nrf2-Mediated Heme Oxygenase-1 Expression in Mouse Hippocampal HT22 Cell Line

Oxidative cell damage contributes to neuronal degeneration in many central nervous system (CNS) diseases such as Parkinson's disease, Alzheimer's disease, and ischemia. Inducible heme oxygenase (HO)-1 acts against oxidants that are thought to play a key role in the pathogenesis of neuronal diseases. The stem bark of Acer nikoense Maxim (Aceraceae) is indigenous to Japan; it has been used in folk medicine as a treatment of hepatic disorders and eye diseases. Acerogenin A, a natural compound isolated from Japanese folk medicine A. nikoense, showed neuroprotective effects and reactive oxygen species (ROS) reduction on glutamate-induced neurotoxicity by inducing the expression of HO-1 in mouse hippocampal HT22 cells. Furthermore, acerogenin A caused the nuclear accumulation of nuclear factor-E2-related factor 2 (Nrf2) and the activation of the PI3K/AKT signaling pathways. In this study, we demonstrated that acerogenin A effectively prevents glutamate-induced oxidative damage, and HO-1 induction via PI3K/Akt and Nrf2 pathways appears to play a key role in the protection of HT22 cells. Therefore, this study implies that the Nrf2/HO-1 pathway represents a biological target and that acerogenin A might be a candidate for the prevention of neurodegeneration.

Healing activity of Casearia sylvestris Sw. in second-degree scald burns in rodents

BACKGROUND

Every year thousands of people are victims of burns, mainly scald burns. Many of these victims have small size wounds and superficial partial thickness and do not seek specialized medical care. As in Brazil Casearia sylvestris Sw., popularly known as guaçatonga is widely used for its analgesic, antiseptic and anti-inflammatory activities, this study sought to evaluate the effects of its hydroalcoholic extract in healing process of burns injuries.

METHODS

The obtained extract was validated applying a thin layer chromatography and sophisticated validation method using Bothrops jararacussu snake venom that is necrotic and inflammatory, and by which guaçatonga extract was able to neutralize the irreversible neuromuscular blockade induced by the venom. After induction of the scald injury, the animals were treated daily with saline solution spray; spray containing extract; biofilm; or biofilm impregnated with extract.

RESULTS

Significant differences were observed between the four groups studied considering: extension of the healing area, neovascularization, fibroblast proliferation, and epithelialization.

CONCLUSION

The anti-inflammatory and bactericidal effects of C. sylvestris Sw. suggests a potential therapeutic benefit in the treatment of inflammatory conditions in second-degree scald burn injuries, as well as, counteracting against the in vitro paralysis induced by B. jararacussu venom.

Neuroprotective activity of hydroponic Teucrium polium following bilateral ovariectomy

Ovariectomy is known as "surgical menopause" with decreased levels of estrogen in female rodents. Its reported risks and adverse effects include cognitive impairment. The action of hydroponic Teucrium polium on nucleus basalis of Meynert (bnM) neurons following 6 weeks of ovariectomy was carried out. The analysis of spike activity was observed by on-line selection and the use of a software package. Early and late tetanic, - posttetanic potentiation and depression of neurons to high frequency stimulation of hippocampus were studied. The complex averaged peri-event time and frequency histograms were constructed. The histochemical study of the activity of Са(2+)-dependent acid phosphatase was observed. In conditions of hydroponic Teucrium polium administration, positive changes in neurons and gain of metabolism leading to cellular survival were revealed. The administration of Teucrium polium elicited neurodegenerative changes in bnM.

Neuroprotection, learning and memory improvement of a standardized extract from Renshen Shouwu against neuronal injury and vascular dementia in rats with brain ischemia

ETHNOPHARMACOLOGICAL RELEVANCE

The Renshen Shouwu capsule (RSSW) is a patented Traditional Chinese Medicine (TCM), that has been proven to improve memory and is widely used in China to apoplexy syndrome and memory deficits. To investigate the neuroprotective and therapeutic effect of the Renshen Shouwu standardized extract (RSSW) on ischemic brain neuronal injury and impairment of learning and memory related to Vascular Dementia (VD) induced by a focal and global cerebral ischemia-reperfusion injury in rats.

MATERIAL AND METHODS

Using in vivo rat models of both focal ischemia/reperfusion (I/R) injuries induced by a middle cerebral artery occlusion (MCAO), and VD with transient global brain I/R neuronal injuries induced by a four-vessel occlusion (4-VO) in Sprague-Dawley (SD) rats, RSSW (50,100, and 200 mg kg(-1) body weights) and Egb761® (80 mg kg(-1)) were administered orally for 20 days (preventively 6 days+therapeutically 14 days) in 4-VO rats, and for 7 days (3 days preventively+4 days therapeutically) in MCAO rats. Learning and memory behavioral performance was assayed using a Morris water maze test including a place navigation trial and a spatial probe trial. Brain histochemical morphology and hippocampal neuron survival was quantified using microscope assay of a puffin brain/hippocampus slice with cresyl violet staining.

RESULTS

MCAO ischemia/reperfusion caused infarct damage in rat brain tissue. 4-VO ischemia/reperfusion caused a hippocampal neuronal lesion and learning and memory deficits in rats. Administration of RSSW (50, 100, and 200mg/kg) or EGb761 significantly reduced the size of the insulted brain hemisphere lesion and improved the neurological behavior of MCAO rats. In addition, RSSW markedly reduced an increase in the brain infarct volume from an I/R-induced MCAO and reduced the cerebral water content in a dose-dependent way. Administration of RSSW also increased the pyramidal neuronal density in the hippocampus of surviving rats after transient global brain ischemia and improved the learning and memory ability of rats with 4-VO induced vascular dementia in a dose-dependent manner.

CONCLUSIONS

The in vivo results suggested that RSSW has significant neuroprotective effects against MCAO and 4-VO I/R injury and a therapeutic effect on cognitive disorders in VD rats. RSSW also improved the learning and memory ability of VD rats. These results convincingly demonstrated that RSSW may be useful to prevent and treat ischemia/reperfusion injury and vascular dementia disease.

Salvia miltiorrhiza: A source for anti-Alzheimer's disease drugs

CONTEXT

Alzheimer's disease (AD) is a devastating neurodegenerative disorder that affects millions of elderly people worldwide. However, no efficient therapeutic method for AD has yet been developed. Recently, Salvia miltiorrhiza Bunge (Lamiaceae), a well-known traditional Chinese medicine which is widely used for treating cardio-cerebrovascular, exerts multiple neuroprotective effects and is attracting increased attention for the treatment of AD.

OBJECTIVE

The objective of this study is to discuss the neuroprotective effects and neurogenesis-inducing activities of S. miltiorrhiza components.

METHODS

A detailed search using major electronic search engines (such as Pubmed, ScienceDirect, and Google Scholar) was undertaken with the search terms: Salvia miltiorrhiza, the components of S. miltiorrhiza such as salvianolic acid B, salvianolic acid A, danshensu, tanshinone I, tanshinone IIA, cryptotanshinone, dihydrotanshinone, and neuroprotection.

RESULTS

Salvia miltiorrhiza components exert multiple neuroprotective potentials relevant to AD, such as anti-amyloid-β, antioxidant, anti-apoptosis, acetylcholinesterase inhibition, and anti-inflammation. Moreover, S. miltiorrhiza promotes neurogenesis of neural progenitor cells/stem cells in vitro and in vivo.

CONCLUSIONS

The properties of S. miltiorrhiza indicate their therapeutic potential in AD via multiple mechanisms. In addition, S. miltiorrhiza provides lead compounds for developing new drugs against AD.

Neuroprotective effects of alkaloids from Piper longum in a MPTP-induced mouse model of Parkinson's disease

CONTEXT

Alkaloids of Piper longum L. (Piperaceae) (PLA) include piperine and piperlonguminine. Piper longum and piperine have multiple biological properties including antioxidant activity.

OBJECTIVE

The present study investigated the neuroprotective effects of PLA in a MPTP-induced mouse model of Parkinson's disease.

MATERIALS AND METHODS

PLA was prepared by extracting the dry seed of P. longum using 85% ethanol. Adult male C57BL/6 mice were divided into eight groups of 12 rats each. Experimental and control groups received an equivalent volume of saline, 0.5% CMC-Na, and 0.1% Tween 80, treated groups received oral PLA (30, 60, and 120 mg/kg), other groups treated with piperine (60 mg/kg) or Madopar (50 mg/kg). The PLA prevention group (PLA-Pr) administrated PLA (120 mg/kg) for 1 week before MPTP challenged. Except for the PLA-Pr group, others were treated for seven consecutive weeks. Parkinson's disease was induced by injecting MPTP intraperitoneally (25 mg/kg) twice weekly for five consecutive weeks. Dopaminerigic (DA) neurons and their metabolism were detected by UFLC-MS/MS. Tyrosine hydroxylase (TH)-immunohistochemistry assay and Western blotting were performed. The antioxidant enzymatic levels were determined by kit-based assays.

RESULTS

The LD50 value of PLA was determined at 1509 mg/kg of body weight. PLA (60 mg/kg) can significantly increase total movement time and distance (p < 0.05), increase levels of DA (p < 0.05) and DOPAC (p <  .05), increase glutathione (GSH) level and superoxide dismutase (SOD) activity (p < 0.05), and decrease the lipid peroxidation of malondiadehycle (MDA) (p < 0.05) in PLA-treated groups as compared with the control group.

DISCUSSION AND CONCLUSION

Our results indicate that PLA possesses neuroprotective effects and has ameliorative properties in dopaminergic neurons.

In vitro antioxidant and anti-cholinesterase activities of Rhizophora mucronata

CONTEXT

Rhizophora mucronata Lam. (Rhizophoraceae), commonly known as Asiatic mangrove, has been used traditionally among Asian countries as folk medicine.

OBJECTIVE

This study investigates the cholinesterase inhibitory potential and antioxidant activities of R. mucronata.

MATERIALS AND METHOD

Rhizophora mucronata leaves were successively extracted using solvents of varying polarity and a dosage of 100-500 µg/ml were used for each assay. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities were assessed according to the method of Ellman. In vitro antioxidant activity was assessed using free radical scavenging, reducing power, and metal-chelating activity (duration - 3 months). Total phenolic and flavonoid content were quantified spectrophotometrically. Compound characterization was done using column chromatography, NMR, FTIR, and LC-MS analysis.

RESULTS

Methanolic leaf extract (500 µg/ml) exhibited the highest inhibitory activity against AChE (92.73 ± 0.54%) and BuChE (98.98 ± 0.17%), with an IC50 value of 59.31 ± 0.35 and 51.72 ± 0.33 µg/ml, respectively. Among the different solvent extracts, methanolic extract exhibited the highest antioxidant activity with an IC50 value of 47.39 ± 0.43, 401.45 ± 18.52, 80.23 ± 0.70, and 316.47 ± 3.56 µg/ml for DPPH, hydroxyl, nitric oxide radical, and hydrogen peroxide, respectively. Total polyphenolic and flavonoid contents in methanolic extract were observed to be 598.13 ± 1.85 µg of gallic acid equivalent and 48.85 ± 0.70 μg of rutin equivalent/mg of extract. Compound characterization illustrated (+)-catechin as the bioactive compound responsible for cholinesterase inhibitory and antioxidant activities.

CONCLUSION

The presence of rich source of flavonoids, in particular catechin, might be responsible for its cholinesterase inhibitory and antioxidant activities.

Protective effect of Convolvulus pluricaulis standardized extract and its fractions against 3-nitropropionic acid-induced neurotoxicity in rats

CONTEXT

Convolvulus pluricaulis Chois. (Convolvulaceae), a well-known Ayurvedic "Medhya Rasayana" (nervine tonic), is extensively used for different central nervous system (CNS) disorders.

OBJECTIVE

The objective of this study was to evaluate the protective effect of standardized hydro-methanol extract of C. pluricaulis (CPE) and its fractions, namely ethyl acetate (EAE), butanol (BE), and aqueous (AE), against 3-nitropropionic acid (3-NP) induced neurotoxicity in rats.

MATERIALS AND METHODS

The extract of the whole plant was standardized on the basis of scopoletin content (0.014%) using thin layer chromatography densitometric analysis. CPE (100 and 200 mg/kg) and its fractions, namely EAE (15 and 30 mg/kg), BE (25 and 50 mg/kg), and AE (50 and 100 mg/kg) were administered orally for 20 d. Their protective effect against 3-NP (10 mg/kg, i.p. for 14 d) was assessed by the effect on various behavioral parameters, namely body weight, locomotor activity, grip strength, gait pattern, and the effect on cognitive dysfunction. Biochemical parameters for oxidative damage were also assessed in the striatum and cortex regions of the brain.

RESULTS

Administration of 3-NP induced HD-like symptoms that were indicated by reduced body weight, locomotor activity, memory, grip strength, and oxidative defense. CPE (200 mg/kg), EAE (30 mg/kg), and BE (50 mg/kg) significantly (p < 0.001) attenuated 3-NP induced reduction in locomotor activity, grip strength, memory, body weight, and oxidative defense in comparison with 3-NP-treated animals on 10 and 15 d.

CONCLUSION

The present study suggested that CPE has a protective action against 3-NP-induced neurotoxicity and can be further explored for its efficacy against Huntington's disease.

Protective effect of centipedegrass against Aβ oligomerization and Aβ-mediated cell death in PC12 cells

CONTEXT

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the abnormal accumulation of β-amyloid (Aβ). Multiple Aβ-aggregated species have been identified, and neurotoxicity appears to be correlated with the amount of non-fibrillar oligomers. Potent inhibitors of Aβ oligomer formation or Aβ-induced cell toxicity have emerged as attractive means of therapeutic intervention. Eremochloa ophiuroide Hack. (Poaceae), also known as centipedegrass (CG), originates from China and South America and is reported to contain several C-glycosyl flavones and phenolic constituents.

OBJECTIVE

We investigated whether CG could suppress Aβ aggregation, BACE1 activity, and toxicity at neuronal cell.

MATERIALS AND METHODS

The inhibitory effect of CG extracts toward aggregation of Aβ42 was investigated in the absence and presence of 50 µg/mL CG. We investigated the inhibitory effects of CG (0-5 µg/mL) on BACE1 using fluorescence resonance energy transfer (FRET)-based assay. The effects of CG (0-75 µg/mL) on Aβ42-induced neurotoxicity were examined in PC12 cells in the presence or absence of maysin and its derivatives of CG.

RESULTS

We isolated EA-CG fraction (70% MeOH fraction from EtOAc extracts) from methanol extracts of CG, which contained approximately 60% maysin and its derivatives. In the present studies, we found that several Aβ oligomeric forms such as the monomer, dimer, trimer, and highly aggregated oligomeric forms were remarkably inhibited in the presence of 50 µg/mL of EA-CG. EA-CG also inhibited BACE1 enzyme activity in a dose-dependent manner. EA-CG treatment generated approximately 50% or 85% inhibition to the control at the tested concentrations of 1 or 5 µg/mL, respectively. Moreover, the neurotoxicity induced by Aβ42 was significantly reduced by treatment of EA-CG, and the 75 µg/mL EA-CG treatment significantly increased cell viability up to 82.5%.

DISCUSSION AND CONCLUSION

These results suggested that the anti-Alzheimer's effects of CG occurred through inhibition of neuronal cell death by intervening with oligomeric Aβ formation and reducing BACE1 activity. Maysin in CG could be an excellent therapeutic candidate for the prevention of AD.

In vitro neuroprotective activities of compounds from Angelica shikokiana Makino

Angelica shikokiana is widely marketed in Japan as a dietary food supplement. With a focus on neurodegenerative conditions such as Alzheimer's disease, the aerial part was extracted and through bio-guided fractionation, fifteen compounds [α-glutinol, β-amyrin, kaempferol, luteolin, quercetin, kaempferol-3-O-glucoside, kaempferol-3-O-rutinoside, methyl chlorogenate, chlorogenic acid, hyuganin E, 5-(hydroxymethyl)-2-furaldehyde, β-sitosterol-3-O-glucoside, adenosine (isolated for the first time from A. shikokiana), isoepoxypteryxin and isopteryxin] were isolated. Isolated compounds were evaluated for in vitro neuroprotection using acetylcholine esterase inhibitory, protection against hydrogen peroxide and amyloid β peptide (Aβ25-35)-induced neurotoxicity in neuro-2A cells, scavenging of hydroxyl radicals and intracellular reactive oxygen species and thioflavin T assays. Quercetin showed the strongest AChE inhibition (IC50 value = 35.5 µM) through binding to His-440 and Tyr-70 residues at the catalytic and anionic sites of acetylcholine esterase, respectively. Chlorogenic acid, its methyl ester, quercetin and luteolin could significantly protect neuro-2A cells against H2O2-induced neurotoxicity and scavenge hydroxyl radical and intracellular reactive oxygen species. Kaempferol-3-O-rutinoiside, hyuganin E and isoepoxypteryxin significantly decreased Aβ25-35-induced neurotoxicity and Th-T fluorescence. To the best of our knowledge, this is the first report about neuroprotection of hyuganin E and isoepoxypteryxin against Aβ25-35-induced neurotoxicity.

Isoflavones with neuroprotective activities from fruits of Cudrania tricuspidata

Ten isoflavones, cudraisoflavones B-K (1-10), together with 27 known isoflavones, were isolated from the EtOAc soluble extract of fruits of Cudrania tricuspidata. The structures of compounds 1-10 were elucidated on the basis of MS and NMR spectroscopic data, including 2D NMR experiments. Compounds 7-9 and three known (11-13) compounds showed neuroprotective activity against 6-hydroxydopamine induced cell death in human neuroblastoma SH-SY5Y cells, with EC50 values of 0.5-9.2 μM.