Examining the neuroprotective effects of protocatechuic acid and chrysin on in vitro and in vivo models of Parkinson disease

Natural Products for the Treatment of Neurodegenerative Diseases

Neurodegenerative diseases are a heterogeneous group of disorders characterized by the progressive degeneration of the structure and function of the central nervous system or peripheral nervous system. Alzheimer's Disease (AD), Parkinson's Disease (PD) and Spinal Cord Injury (SCI) are the common neurodegenerative diseases, which typically occur in people over the age of 60. With the rapid development of an aged society, over 60 million people worldwide are suffering from these uncurable diseases. Therefore, the search for new drugs and therapeutic methods has become an increasingly important research topic. Natural products especially those from the Traditional Chinese Medicines (TCMs), are the most important sources of drugs, and have received extensive interest among pharmacist. In this review, in order to facilitate further chemical modification of those useful natural products by pharmacists, we will bring together recent studies in single natural compound from TCMs with neuroprotective effect.

p62-Nrf2-p62 Mitophagy Regulatory Loop as a Target for Preventive Therapy of Neurodegenerative Diseases

Turnover of the mitochondrial pool due to coordinated processes of mitochondrial biogenesis and mitophagy is an important process in maintaining mitochondrial stability. An important role in this process is played by the Nrf2/ARE signaling pathway, which is involved in the regulation of the expression of genes responsible for oxidative stress protection, regulation of mitochondrial biogenesis, and mitophagy. The p62 protein is a multifunctional cytoplasmic protein that functions as a selective mitophagy receptor for the degradation of ubiquitinated substrates. There is evidence that p62 can positively regulate Nrf2 by binding to its negative regulator, Keap1. However, there is also strong evidence that Nrf2 up-regulates p62 expression. Thereby, a regulatory loop is formed between two important signaling pathways, which may be an important target for drugs aimed at treating neurodegeneration. Constitutive activation of p62 in parallel with Nrf2 would most likely result in the activation of mTORC1-mediated signaling pathways that are associated with the development of malignant neoplasms. The purpose of this review is to describe the p62-Nrf2-p62 regulatory loop and to evaluate its role in the regulation of mitophagy under various physiological conditions.

Involvement of PTEN and FOXO3a Proteins in the Protective Activity of Protocatechuic Acid Against Cisplatin-Induced Ovarian Toxicity in Mice

The present study evaluated the effects of protocatechuic acid (PCA) after cisplatin-induced ovarian toxicity in mice and if PTEN and FOXO3a proteins are involved in PCA action. The mice were divided into five experimental groups (five animals per group) and treated once a day for 3 days as follows: (1) the control group was pretreated with oral administration (o.p.) of saline solution, followed by an intraperitoneal (i.p.) injection of saline solution. The other groups were pretreated (o.p.) with (2) saline solution (cisplatin group), (3) N-acetylcysteine (150 mg/kg of body weight), or with (4) 20 or (5) 50 mg/kg body weight of PCA, followed by 5 mg/kg body weight (i.p.) of cisplatin. Next, the ovaries were destined to histological (morphology and activation), immunohistochemical (PCNA and cleaved caspase-3 expression), and fluorescence (reactive oxygen species [ROS], glutathione [GSH], and active mitochondria levels) analyses. Moreover, the immunoreactivity for p-PTEN and p-FOXO3a was evaluated to investigate a potential mechanism by which PCA could prevent the cisplatin-induced ovarian damage. Pretreatment with N-acetylcysteine or 20 mg/kg PCA before cisplatin preserved the percentage of normal follicles and cell proliferation as observed in the control, reduced apoptosis and ROS levels, and showed higher active mitochondria and GSH levels than the cisplatin treatment (P < 0.05). Moreover, pretreatment with 20 mg/kg PCA decreased cisplatin-induced p-PTEN and increased (P < 0.05) nuclear export of p-FOXO3a. In conclusion, PCA at 20 mg/kg reduced apoptosis, maintained cell proliferation and mitochondrial function, reduced ROS production, and increased GSH expression likely through the involvement of PTEN and FOXO3a proteins.

Effects of protocatechuic acid on ameliorating lipid profiles and cardio-protection against coronary artery disease in high fat and fructose diet fed in rats

A coronary heart disease leads to increase in obesity and metabolic dysfunction. Protocatechuic acid (PCA), due to its antioxidant, anti-inflammatory, neuro protective activities was found efficient as cardio-protective in coronary heart disease. Our study investigated hypolipidemic and cardioprotective effects of protocatechuic acid in the coronary artery disease induced by high fat and fructose diet (HFD) rat models. A diet rich in fat and fructose was fed to male Wistar rats prior to the start of experimental procedures. Serum lipid levels and hepatic triglycerides (TG) and total cholesterol (TC) levels were examined and analyzed. Both in vitro an in vivo pancreatic lipase activity was determined as well. Histopathological examination was performed and their results were noted. Noteworthy reduction of serum lipid levels and hepatic TG and TC levels was seen in groups treated with simvastatin (SIM; 20 mg/kg) and PCA (50 and 100 mg/kg) in comparison to HFD groups. Pancreatic lipase activity was reduced in the SIM group and the group treated with doses of PCA (50 and 100 mg/kg). A marked increase in gain in body weight per week (P<0.05) was achieved in HFD group. Coronary risk index (CRI) and Atherogenic index of plasma (AIP) showed decreased index values after treatments with SIM and PCA (50 and 100 mg/kg), respectively. Our findings confirmed the efficacious cardio-protective and hypolipidaemic activities of protocatechuic acid in coronary artery disease induced in rats with fat and fructose rich diet.

Molecular mechanism-based therapeutic properties of honey

Honey and its phenolic compounds specifically chrysin are focused as nutritional supplements and likewise as valued phytochemicals, nutraceuticals, and phytopharmaceuticals alone, or adjuvant with some conventional medications to cause synergistic therapeutic or cytotoxic effects. Through the verified beneficial strategies combat several disturbances, phenolic compounds play fundamental functions in the avoidance and treatment of disorders. Oxidative stress, inflammation, and apoptosis are the three most imperative physiological reactions in the prevalence of numerous ailments. Honey, chrysin, and other phenolic compounds detected in honey can modify clinical conditions via modulation of these contrivances and correlated signaling pathways. The current study desires to review the therapeutic effects of honey and its allied molecular mechanisms. Evidenced-base studies show that honey would represent therapeutic potential against various types of cancer and tumor proliferation (colorectal cancer, breast cancer, bladder cancer, leukemia, glioma, hepatocellular cancer, pancreatic cancer, and melanoma), wounds, diabetes mellitus, neurological (depression, Parkinson disease, and Alzheimer's disease), respiratory, gastrointestinal (peptic ulcer and ulcerative colitis), cardiovascular disorders, renal injuries, liver diseases and many other kinds of physiological dysfunctionalities through various molecular mechanisms contributed with oxidative stress, inflammatory process, and apoptosis.

New progress in the pharmacology of protocatechuic acid: A compound ingested in daily foods and herbs frequently and heavily

Protocatechuic acid is a natural phenolic acid, which widely exists in our daily diet and herbs. It is also one of the main metabolites of complex polyphenols, such as anthocyanins and proanthocyanins. In recent years, a large number of studies on the pharmacological activities of protocatechuic acid have emerged. Protocatechuic acid has a wide range of pharmacological activities including antioxidant, anti-inflammatory, neuroprotective, antibacterial, antiviral, anticancer, antiosteoporotic, analgesia, antiaging activties; protection from metabolic syndrome; and preservation of liver, kidneys, and reproductive functions. Pharmacokinetic studies showed that the absorption and elimination rate of protocatechuic acid are faster, with glucuronidation and sulfation being the major metabolic pathways. However, protocatechuic acid displays a dual-directional regulatory effect on some pharmacological activities. When the concentration is very high, it can inhibit cell proliferation and reduce survival rate. This review aims to comprehensively summarize the pharmacology, pharmacokinetics, and toxicity of protocatechuic acid with emphasis on its pharmacological activities discovered in recent 5 years, so as to provide more up-to-date and thorough information for the preclinical and clinical research of protocatechuic acid in the future. Moreover, it is hoped that the clinical application of protocatechuic acid can be broadened, giving full play to its characteristics of rich sources, low toxicity and wide pharmacological activites.

Lessons from Exploring Chemical Space and Chemical Diversity of Propolis Components

Propolis is a natural resinous material produced by bees and has been used in folk medicines since ancient times. Due to it possessing a broad spectrum of biological activities, it has gained significant scientific and commercial interest over the last two decades. As a result of searching 122 publications reported up to the end of 2019, we assembled a unique compound database consisting of 578 components isolated from both honey bee propolis and stingless bee propolis, and analyzed the chemical space and chemical diversity of these compounds. The results demonstrated that both honey bee propolis and stingless bee propolis are valuable sources for pharmaceutical and nutraceutical development.

Protocatechuic Acid Extends Survival, Improves Motor Function, Diminishes Gliosis, and Sustains Neuromuscular Junctions in the hSOD1G93A Mouse Model of Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a devastating disorder characterized by motor neuron apoptosis and subsequent skeletal muscle atrophy caused by oxidative and nitrosative stress, mitochondrial dysfunction, and neuroinflammation. Anthocyanins are polyphenolic compounds found in berries that possess neuroprotective and anti-inflammatory properties. Protocatechuic acid (PCA) is a phenolic acid metabolite of the parent anthocyanin, kuromanin, found in blackberries and bilberries. We explored the therapeutic effects of PCA in a transgenic mouse model of ALS that expresses mutant human Cu, Zn-superoxide dismutase 1 with a glycine to alanine substitution at position 93. These mice display skeletal muscle atrophy, hindlimb weakness, and weight loss. Disease onset occurs at approximately 90 days old and end stage is reached at approximately 120 days old. Daily treatment with PCA (100 mg/kg) by oral gavage beginning at disease onset significantly extended survival (121 days old in untreated vs. 133 days old in PCA-treated) and preserved skeletal muscle strength and endurance as assessed by grip strength testing and rotarod performance. Furthermore, PCA reduced astrogliosis and microgliosis in spinal cord, protected spinal motor neurons from apoptosis, and maintained neuromuscular junction integrity in transgenic mice. PCA lengthens survival, lessens the severity of pathological symptoms, and slows disease progression in this mouse model of ALS. Given its significant preclinical therapeutic effects, PCA should be further investigated as a treatment option for patients with ALS.

Chrysin Protects against Memory and Hippocampal Neurogenesis Depletion in D-Galactose-Induced Aging in Rats

The interruption of hippocampal neurogenesis due to aging impairs memory. The accumulation of D-galactose (D-gal), a monosaccharide, induces brain aging by causing oxidative stress and inflammation, resulting in neuronal cell damage and memory loss. Chrysin, an extracted flavonoid, has neuroprotective effects on memory. The present study aimed to investigate the effect of chrysin on memory and hippocampal neurogenesis in brains aged using D-gal. Male Sprague-Dawley rats received either D-gal (50 mg/kg) by i.p. injection, chrysin (10 or 30 mg/kg) by oral gavage, or D-gal (50 mg/kg) and chrysin (10 or 30 mg/kg) for 8 weeks. Memory was evaluated using novel object location (NOL) and novel object recognition (NOR) tests. Hippocampal neurogenesis was evaluated using Ki-67, 5-bromo-2′-deoxyuridine (BrdU), and doublecortin (DCX) immunofluorescence staining to determine cell proliferation, cell survival, and number of immature neurons, respectively. We found that D-gal administration resulted in memory impairment as measured by NOL and NOR tests and in depletions in cell proliferation, cell survival, and immature neurons. However, co-treatment with chrysin (10 or 30 mg/kg) attenuated these impairments. These results suggest that chrysin could potentially minimize memory and hippocampal neurogenesis depletions brought on by aging.

Protective effects of organic extracts of Alpinia oxyphylla against hydrogen peroxide-induced cytotoxicity in PC12 cells

Alpinia oxyphylla, a traditional herb, is widely used for its neuroprotective, antioxidant and memory-improving effects. However, the neuroprotective mechanisms of action of its active ingredients are unclear. In this study, we investigated the neuroprotective effects of various organic extracts of Alpinia oxyphylla on PC12 cells exposed to hydrogen peroxide-induced oxidative injury in vitro. Alpinia oxyphylla was extracted three times with 95% ethanol (representing extracts 1–3). The third 95% ethanol extract was dried and resuspended in water, and then extracted successively with petroleum ether, ethyl acetate and n-butanol (representing extracts 4–6). The cell counting kit-8 assay and microscopy were used to evaluate cell viability and observe the morphology of PC12 cells. The protective effect of the three ethanol extracts (at tested concentrations of 50, 100 and 200 µg/mL) against cytotoxicity to PC12 cells increased in a concentration-dependent manner. The ethyl acetate, petroleum ether and n-butanol extracts (each tested at 100, 150 and 200 μg/mL) had neuroprotective effects as well. The optimum effective concentration ranged from 50–200 μg/mL, and the protective effect of the ethyl acetate extract was comparatively robust. These results demonstrate that organic extracts of Alpinia oxyphylla protect PC12 cells against apoptosis induced by hydrogen peroxide. Our findings should help identify the bioactive neuroprotective components in Alpinia oxyphylla.

Neuroprotective Dihydro-β-agarofuran-Type Sesquiterpenes from the Seeds of Euonymus maackii

Twenty-one dihydro-β-agarofuran derivatives were purified from the seeds of Euonymus maackii, and eight compounds (1-8) were identified as new natural products. Their structures were deduced by extensive spectroscopic analysis, X-ray diffraction studies, and comparison of observed and reported NMR data. Compounds 10, 12, 17, and 18 significantly increased the cell viability of Aβ_25-35-treated SH-SY5Y cells with effects similar to that of epigallocatechin gallate (EGCG). In addition, the abundant compound 9 reduced the seizure-like locomotor activity of zebrafish at 10 μM compared with a pentylenetetrazol-treated group.

Shaping the Nrf2-ARE-related pathways in Alzheimer's and Parkinson's diseases

A failure in redox homeostasis is a common hallmark of Alzheimer's Disease (AD) and Parkinson's Disease (PD), two age-dependent neurodegenerative disorders (NDD), causing increased oxidative stress, oxidized/damaged biomolecules, altered neuronal function and consequent cell death. Activation of nuclear factor erythroid 2-related factor 2 (Nrf2), a redox-regulated transcription factor, results in upregulation of cytoprotective and antioxidant enzymes/proteins, protecting against oxidative stress. Nrf2 regulation is achieved by various proteins and pathways, at both cytoplasmatic and nuclear level; however, the elaborate network of mechanisms involved in Nrf2 regulation may restrain Nrf2 pathway normal activity. Indeed, altered Nrf2 activity is involved in aging and NDD, such as AD and PD. Therefore, understanding the diversity of Nrf2 control mechanisms and regulatory proteins is of high interest, since more effective NDD therapeutics can be identified. In this review, we first introduce Keap1-Nrf2-ARE structure, function and regulation, with a special focus on the several pathways involved in Nrf2 positive and negative modulation, namely p62, PKC, PI3K/Akt/GSK-3β, NF-kB and p38 MAPK. We then briefly describe the evidences for oxidative stress and Nrf2 pathway deregulation in different stages of NDDs. Finally, we discuss the potential of Nrf2-related pathways as potential therapeutic targets to possibly prevent or slowdown NDD progression.

Chrysin: Pharmacological and therapeutic properties

Chrysin is a promising phytochemical that is categorized under the class of flavonoids based on its chemical structure. Naturally, it is widely present in propolis, honey, passion fruit, and even in mushrooms and other plant sources, whereas its synthetic counterparts are also being employed for pharmacological purposes. It has widely been employed in treatment of various degenerative disorders and provides cytotoxic and anti-inflammatory functions. Its antioxidant and disease preventing abilities are attributed to its structural diversity arising in ring-A and absence of oxygenation in B and C ring. In this review, the scientific studies are being reported emphasizing benefits and its allied health claims on chrysin in numerous metabolic malfunctions.

Anthocyanins and Their Metabolites as Therapeutic Agents for Neurodegenerative Disease

Neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis (ALS), are characterized by the death of neurons within specific regions of the brain or spinal cord. While the etiology of many neurodegenerative diseases remains elusive, several factors are thought to contribute to the neurodegenerative process, such as oxidative and nitrosative stress, excitotoxicity, endoplasmic reticulum stress, protein aggregation, and neuroinflammation. These processes culminate in the death of vulnerable neuronal populations, which manifests symptomatically as cognitive and/or motor impairments. Until recently, most treatments for these disorders have targeted single aspects of disease pathology; however, this strategy has proved largely ineffective, and focus has now turned towards therapeutics which target multiple aspects underlying neurodegeneration. Anthocyanins are unique flavonoid compounds that have been shown to modulate several of the factors contributing to neuronal death, and interest in their use as therapeutics for neurodegeneration has grown in recent years. Additionally, due to observations that the bioavailability of anthocyanins is low relative to that of their metabolites, it has been proposed that anthocyanin metabolites may play a significant part in mediating the beneficial effects of an anthocyanin-rich diet. Thus, in this review, we will explore the evidence evaluating the neuroprotective and therapeutic potential of anthocyanins and their common metabolites for treating neurodegenerative diseases.

Metal Chelation Therapy and Parkinson's Disease: A Critical Review on the Thermodynamics of Complex Formation between Relevant Metal Ions and Promising or Established Drugs

The present review reports a list of approximately 800 compounds which have been used, tested or proposed for Parkinson's disease (PD) therapy in the year range 2014-2019 (April): name(s), chemical structure and references are given. Among these compounds, approximately 250 have possible or established metal-chelating properties towards Cu(II), Cu(I), Fe(III), Fe(II), Mn(II), and Zn(II), which are considered to be involved in metal dyshomeostasis during PD. Speciation information regarding the complexes formed by these ions and the 250 compounds has been collected or, if not experimentally available, has been estimated from similar molecules. Stoichiometries and stability constants of the complexes have been reported; values of the cologarithm of the concentration of free metal ion at equilibrium (pM), and of the dissociation constant Kd (both computed at pH = 7.4 and at total metal and ligand concentrations of 10-6 and 10-5 mol/L, respectively), charge and stoichiometry of the most abundant metal-ligand complexes existing at physiological conditions, have been obtained. A rigorous definition of the reported amounts is given, the possible usefulness of this data is described, and the need to characterize the metal-ligand speciation of PD drugs is underlined.

Protocatechuic acid attenuate depressive-like behavior in olfactory bulbectomized rat model: behavioral and neurobiochemical investigations

The main objective of the present study is to investigate potential effects of PCA in OBX induced depressive-like behavior in rat model. PCA was administered at a dose of 100 mg/kg and 200 mg/kg, by per oral in OBX and sham operated rats. Behavioral (ambulatory and rearing activity and immobility time), neurochemical [serotonin (5-HT), dopamine (DA), norepinephrine (NE) and brain derived neurotrophic factor (BDNF) expression], biochemical (MDA formation, IL-6, TNF-α and antioxidants) changes in hippocampus and cerebral cortex along with serum corticosterone were investigated. Experimental findings reveals that OBX subjected rats showed alteration in behaviors like, increase in immobility time, ambulatory and rearing behaviors significantly, reduced BDNF level, 5-HT, DA,NE and antioxidant parameters along with increased serum corticosterone, MDA formation, IL-6, and TNF-α in hippocampus and cerebral cortex compared to sham operated rats. Administration of PCA significantly attenuated behavioral and neurobiochemical alterations, thus, its antidepressant-like activity is largely mediated through modulation of neurotransmitter, endocrine and immunologic systems, mainly by improvements of BDNF, 5-HT, DA, NE, reduced MDA, IL-6, and TNF-α in hippocampus and cerebral cortex.

Protective Influence of Phyllanthus Muellarianus on Ciprofloxacin-Induced Neurotoxicity in Male Rats

Phyllanthus muellarianus (Kuntze) Exell. (Euphorbiacea) leaves are widely used in the treatment of neurological disorders in Nigeria. We investigated the protective effect of aqueous leaf extract of Phyllanthus muellarianus on ciprofloxacin neurotoxicity in male rats. Control rats (Group A) received distilled water, Groups C-E According to the Animal grouping and treatment section, Group B did not receive P. muellarianus> rats were administered 100, 200, and 400 mg/kg body weight P. muellarianus, respectively, and Group F rats received 200 mg/kg body weight valproate orally for 7 days. In addition, groups B-F rats were orally administered ciprofloxacin for 7 days. Motor coordination and motor function were assessed using narrow beam and landing foot splay distance. The levels of neurotransmitter and oxidative stress biomarkers were also determined. Aqueous leaf extract of P. muellarianus significantly attenuated ciprofloxacin-mediated increases in narrow beam, landing foot splay distance, and gait scores. Ciprofloxacin-mediated depletion of acetylcholine and dopamine in the brains of rats was significantly annulled by P. muellarianus. Furthermore, the extract significantly reversed ciprofloxacin-mediated increases in acetylcholinesterase, monoamine oxidase A, and monoamine oxidase B by 73.13%, 71.52%, and 86.54%, respectively. The altered biomarkers of oxidative stress were significantly reversed by P. muellarianus. Overall, the results of this study show that P. muellarianus reversed ciprofloxacin-induced neurotoxicity by restoring ciprofloxacin-mediated alterations in acetylcholine, dopamine, acetylcholinesterase, monoaminergic enzymes, and oxidative stress biomarkers in the brains of rats.

Protocatechuic acid exerts protective effects via suppression of the P38/JNK- NF-κB signalling pathway in an experimental mouse model of intracerebral haemorrhage

Protocatechuic acid (PCA) has been well studied for its neuroprotection value in several diseases, but the effect in intracerebral haemorrhage (ICH) has not been reported. Here we verified the protection of PCA in ICH, and investigated the relative mechanisms. ICH model mice were established by injection of collagenase IV. The mice were treated with PCA once per day for 3 days, starting immediately after operation. The modified neurological severity score (mNSS) of mice at 1st, 3rd and 7th day after operation were recorded. And some of mice were euthanized at 3rd day to compare brain water content, pro-inflammatory cytokines expression, and cell apoptosis in perihematomal tissue. Additionally, SH-SY5Y cells were treated hemin to mimic secondary injury of ICH. Cells were incubated with PCA for treatment. The cell viability, ROS, apoptosis rate and protein expression of apoptosis-relative protein and MAPKs and NF-κB were detected and analysed. The results revealed PCA alleviated the cerebral oedema at 3rd post ICH, and significantly improved neurological functions. PCA also attenuated the protein and gene expression of TNF-а, IL-1β and IL-6 vivo. PCA dose-dependently decreased the generation of ROS and apoptosis rate. Furthermore, PCA treatment dose-dependently decreased the expression of bax, cleaved caspase-3, increased bcl-2 expression; PCA downregulated P38/JNK-NF-κB pathway. In conclusion, PCA effectively improves prognosis of ICH mice by inhibiting oxidative stress, inflammation and apoptosis. The mechanism possibly results of downregulating of P38/JNK-NF-κB pathway, and PCA can be a potential therapeutic agent for ICH.

Tissue Distribution of Active Principles from Alpiniae Oxyphyllae Fructus Extract: An Experimental Study in Rats

Background:

Alpiniae Oxyphyllae Fructus (Yizhi in Chinese) have been widely used as an herbal medicine for the treatment of diuresis, enuresis and diarrhea in China. Many studies have deciphered some potential underlying mechanisms for its anti-diarrheal effects. However, tissue distribution of Yizhi constituents is warranted because pharmacological receptors are frequently located in tissues. Moreover, it is also interesting to know about the potential correlation between behavior in drug distribution and the observed pharmacological response. The aim of this study is to investigate tissue distribution behaviors of Yizhi constituents after oral administration of Yizhi extract to rats, focusing on 10 active principles.

Methods:

Twenty four male Sprague Dawley rats were given orally the Yizhi extract and fourteen tissue samples were collected after being killed by bleeding from the abdominal aorta under ether anesthesia at different time-points. The resulting tissues were excised and homogenized. Based on our previous reports, liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was used to quantify the target analytes, as well as phase II metabolites, in the various biosamples.

Results:

Almost all the targeted Yizhi active principles and some glucuronidated metabolites were qualitatively measured in rat stomach, small intestine, large intestine, as well as liver. Nootkatone, yakuchinone A and tectochrysin were observed in the rat brain. In other rat tissues, these analytes had lower exposure or could not be detected. Consistently, quantitative analysis revealed that the Yizhi active principles dominantly distributed into gastrointestinal tissues followed by liver, the overall exposure levels ranking as follows: stomach > small intestine > large intestine > liver. Tissue concentrationtime profiles of the test active principles in rat stomach, small intestine, and large intestine were bimodal with two concentration peaks occurring at 0.5 and 4h after oral administration, respectively. The exposure levels in rat kidney and bladder were quite low.

Conclusion:

The active principles of Yizhi were specially distributed into gastrointestinal tissues after oral administration of its ethanol extract to rats. The tissue distribution behaviors partly supported its anti-diarrheal effects from a pharmacokinetic opinion. This paper will be useful as the starting point for studying the pharmacological activities of this traditional herb.

Sophora Tomentosa Extract Prevents MPTP-Induced Parkinsonism in C57BL/6 Mice Via the Inhibition of GSK-3β Phosphorylation and Oxidative Stress

Sophora species are used as dietary medicines in aging-associated symptoms. Sophora tomentosa L. (ST) is a native medicinal plant in Southeast Asia; however, there is no pharmacological literature about ST extract. The present study evaluates the antioxidant phytoconstituent contents and radical scavenging capacities of ST extract. The further investigation was to clarify the neuroprotective mechanism of ST extract against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinsonism by assaying the activities of the dopaminergic system and antioxidant defenses, glycogen synthase kinase 3β (GSK3-β) phosphorylation, and α-synuclein levels in C57BL/6 mice. The results show that ST extract alleviated the motor deficits in MPTP-induced Parkinsonism with four behavioral tests, including a rearing locomotor, catalepsy test, balance beam walking test, and pole test. ST extract reversed the number of tyrosine hydroxylase (TH)-positive neurons in substantia nigra (SN) that had decreased by MPTP. ST extract also restored the decreased levels of dopamine and the expression of tyrosine hydroxylase (TH) in the striatum. Furthermore, ST extract restored the levels of glutathione (GSH) and the activities of antioxidant enzymes, and decreased the elevated levels of malondialdehyde (MDA) in mouse striatum. ST extract also decreased α-synuclein overexpression and GSK-3β phosphorylation in mouse striatum. In vitro, ST extract exerted higher 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging capacities through its higher phenolic contents, especially protocatechuic acid and epicatechin. These results suggest that ST extract has the potential to counteract MPTP-induced motor deficit. The neuroprotective mechanism of ST extract against MPTP-induced Parkinsonism might be related to decreasing GSK-3β phosphorylation and restoring the activities of striatal antioxidant defenses to restore the nigrostriatal dopaminergic function and decrease α-synuclein accumulation.

Protocatechuic acid improves functional recovery after spinal cord injury by attenuating blood-spinal cord barrier disruption and hemorrhage in rats

After spinal cord injury (SCI), blood-spinal cord barrier (BSCB) disruption and hemorrhage lead to blood cell infiltration and progressive secondary injuries including inflammation. Inflammatory response is one of the major events resulting in apoptosis, scar formation and neuronal dysfunction after SCI. Here, we investigated whether protocatechuic acid (PCA), a natural phenolic compound, would attenuate BSCB disruption and hemorrhage, leading to functional improvement after SCI. After a moderate contusion injury at T9, PCA (50 mg/kg) was administrated via intraperitoneal injection immediately, 6 h, and 12 h after SCI, and the same dose of PCA once a day until 7 d after injury. Our data show that PCA inhibited apoptotic cell death of neurons and oligodendrocytes and improved functional recovery after injury. PCA also attenuated BSCB disruption and hemorrhage and reduced the infiltration of neutrophils and macrophages compared to vehicle control. Moreover, PCA inhibited the expression and activation of matrix metalloprotease-9, which is well known to disrupt BSCB after SCI. Furthermore, PCA treatment significantly inhibited the expression of sulfonylurea receptor 1 and transient receptor potential melastatin 4, which are known to mediate hemorrhage at an early stage after SCI. Consistent with these findings, the mRNA and protein expression of inflammatory mediators such as tumor necrosis factor alpha, interleukin 1 beta, cyclooxygenase-2, inducible nitric oxide synthase, and chemokines was significantly alleviated by PCA treatment. Thus, our results suggest that PCA improved functional recovery after SCI in part by inhibiting BSCB disruption and hemorrhage through the down-regulation of sulfonylurea receptor 1/transient receptor potential melastatin 4 and matrix metalloprotease-9.

Protocatechuic Acid Ameliorated Palmitic-Acid-Induced Oxidative Damage in Endothelial Cells through Activating Endogenous Antioxidant Enzymes via an Adenosine-Monophosphate-Activated-Protein-Kinase-Dependent Pathway

Protocatechuic acid (PCA, 3,4-dihydroxybenzoic acid), the main metabolite of anthocyanins, is widely distributed in fruits and vegetables and has been reported to possess a strong antioxidant activity. Herein, we aimed to investigate the protective effect of PCA against high palmitic-acid (PA)-induced oxidative damage and the underling molecular mechanisms in human umbilical vein endothelial cells (HUVECs). PCA reduced the levels of intracellular reactive oxygen species and malondialdehyde and increased the activities of endogenous antioxidant enzymes, including superoxide dismutase, glutathione peroxidase 1, and heme oxygenase 1 (HO-1). Metabolomic analysis showed that PCA affected numerous metabolites, especially some of which were related with energy metabolism. PCA also upregulated the phosphorylation of adenosine-monophosphate-activated protein kinase (AMPK) at Thr¹⁷² through activating liver kinase B1 and then promoted the expression of p-Nrf2 and HO-1. Moreover, PCA reversed the decreased expression of peroxisome proliferator-activated receptor γ coactivator 1α and significantly increased the mitochondrial density. Collectively, these results demonstrated that PCA attenuated PA-induced oxidative damage in HUVECs via an AMPK-dependent pathway.

Ethnopharmacological uses, phytochemistry, biological activities, and therapeutic applications of Alpinia oxyphylla Miquel: A review

ETHNOPHARMACOLOGICAL USAGES

Fructus Alpiniae oxyphyllae (A. oxyphylla) is an important medicinal plant that is used not only as an edible fruit, but also as an important traditional medicine for benefiting cognitive performance and alleviating a wide spectrum of diseases. Such as; warming kidney, securing essence and arresting polyuria, as well as warming the spleen and stopping diarrhea and saliva.

AIMS

The purpose of this review is to provide updated, comprehensive and categorized information on the traditional uses, phytochemistry and pharmacological research of A. oxyphylla in order to explore their therapeutic potential and establish a solid foundation for directing future research.

MATERIALS AND METHODS

All the available information on A. oxyphylla was collected via electronic search (using Pubmed, SciFinder, Scirus, Google Scholar and Web of Science) and additionally a number of unpublished resources, (e.g. books, Ph.D. and M.Sc. dissertations, government reports).

RESULTS

Phytochemical research on A. oxyphylla has led to the isolation of components such as essential oils, terpenes, diarylheptanoids, flavones, nucleobases and nucleosides, steroids and others. Crude extracts, fractions and phytochemical constituents isolated from A. oxyphylla showed a wide spectrum of in vitro and in vivo pharmacological activities like neuroprotective, anti-diarrheal, anti-diuretic, anti-neoplastic, anti-oxidant, anti-inflammatory, anti-allergic, viscera protective and anti-diabetic activities. Neuroprotective, anti-cancer, anti-diarrheal and anti-diuretic effects are major areas of research conducted on A. oxyphylla.

CONCLUSIONS

Modern pharmacological studies have supported many traditional uses of A. oxyphylla, including nervous system, urinary system and gastrointestinal system disease. There was convincing evidence in experimental animal models in support of its neuroprotection, secure essence, reduce urination, and anti-carcinogenic effects. However, all the reported pharmacological activities were carried out at pre-clinical level and the authors urge further investigation in clinical trials about these therapeutic fields of A. oxyphylla.

Safety evaluation, anti-oxidative and anti-inflammatory effects of subchronically dietary supplemented high dosing grape seed powder (GSP) to healthy rat

Grape seed powder (GSP) contains high amount of bioactive polyphenols usually used as nutritional supplement or food preservatives due to their antioxidant and scavenging properties. The purpose of the present work was to evaluate the safety of increasing dosage GSP (w/w) of 0.5%, 5%, 10% and 20% corresponding to 0.4, 4, 8 and 16 g/kg bw respectively, when administered sub-chronically to Wistar rats in a 2 month-repeated dosing oral toxicity trial. Overally GSP had no effect on food intake, decreased body weight gain without affecting brain, liver, heart or kidney relative weight. GSP did not alter haematology except an increase in platelets, slightly decreased plasma transaminases, creatinine, urea and xanthine oxidase activity, without affecting uricemia, glycemia, triglyceridemia and cholesterolemia. GSP did not affect intracellular mediators as calcium, free iron or H₂O₂, but exerted real anti-oxidative properties in the four selected organs as assessed by lower lipoperoxidation and carbonylation, higher non protein thiols and antioxidant enzyme activities as CAT, GPx and SOD. Besides GSP exerted anti-inflammatory properties as supported by lower plasma IL17 A and CRP and higher IL10 and adiponectin. Histopathologically GSP provoked the dilation of heart and kidney arterioles and increased the size of the hippocampal dentate gyrus reflecting higher neurogenesis as assessed by Ki-67 labeling. Under the experimental conditions of the current study, GSP appeared as highly safe even when administered at very high dosage and could find potential applications in a variety of biotic or abiotic stresses-induced multi-organ dysfunction.

Targeting mTORs by omega-3 fatty acids: A possible novel therapeutic strategy for neurodegeneration?

Neurodegenerative diseases (NDs) such as Parkinson's (PD), Alzheimer's (AD), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS) cause significant world-wide morbidity and mortality. To date, there is no drug of cure for these, mostly age-related diseases, although approaches in delaying the pathology and/or giving patients some symptomatic relief have been adopted for the last few decades. Various studies in recent years have shown the beneficial effects of omega-3 poly unsaturated fatty acids (PUFAs) through diverse mechanisms including anti-inflammatory effects. This review now assesses the potential of this class of compounds in NDs therapy through specific action against the mammalian target of rapamycin (mTOR) signaling pathway. The role of mTOR in neurodegenerative diseases and targeted therapies by PUFAs are discussed.

Polyphenols in Parkinson's Disease: A Systematic Review of In Vivo Studies

Parkinson's disease (PD) is the second most common neurodegenerative disorder. However, therapeutic options treating only its symptoms are very disappointing. Therefore there is an ongoing search for compounds capable of tackling the multi-dimensional features of PD. Recently natural polyphenols have gained great interest as potential therapeutic agents. Herein, we have attempted to summarize results obtained in different animal models demonstrating their neuroprotective effects. The in vivo findings presented below are supported by human subject data and reports regarding the ability of polyphenols to cross the blood-brain barrier. The beneficial effects of polyphenols are demonstrated by the results of behavioral examinations, mainly related to motor and cognitive capabilities, histopathological and immunohistochemical examination concerning the protection of dopaminergic neurons, analyses of dopamine and the concentration of its metabolites, as well as mechanistic studies regarding the modulation of oxidative stress, neuroinflammation, cellular iron management, proteinopathy, and additionally the regulation of signaling pathways. Importantly, data about brain distribution of the metabolic derivatives of the reviewed polyphenols are crucial for the justification of their nutritional intake in neuroprotective intervention, as well as for the identification of potential targets for a novel therapeutic approach to Parkinson's disease.

Effects of Protocatechuic Acid (PCA) on Global Cerebral Ischemia-Induced Hippocampal Neuronal Death

Global cerebral ischemia (GCI) is one of the main causes of hippocampal neuronal death. Ischemic damage can be rescued by early blood reperfusion. However, under some circumstances reperfusion itself can trigger a cell death process that is initiated by the reintroduction of blood, followed by the production of superoxide, a blood⁻brain barrier (BBB) disruption and microglial activation. Protocatechuic acid (PCA) is a major metabolite of the antioxidant polyphenols, which have been discovered in green tea. PCA has been shown to have antioxidant effects on healthy cells and anti-proliferative effects on tumor cells. To test whether PCA can prevent ischemia-induced hippocampal neuronal death, rats were injected with PCA (30 mg/kg/day) per oral (p.o) for one week after global ischemia. To evaluate degenerating neurons, oxidative stress, microglial activation and BBB disruption, we performed Fluoro-Jade B (FJB), 4-hydroxynonenal (4HNE), CD11b, GFAP and IgG staining. In the present study, we found that PCA significantly decreased degenerating neuronal cell death, oxidative stress, microglial activation, astrocyte activation and BBB disruption compared with the vehicle-treated group after ischemia. In addition, an ischemia-induced reduction in glutathione (GSH) concentration in hippocampal neurons was recovered by PCA administration. Therefore, the administration of PCA may be further investigated as a promising tool for decreasing hippocampal neuronal death after global cerebral ischemia.

Ponatinib exerts anti-angiogenic effects in the zebrafish and human umbilical vein endothelial cells via blocking VEGFR signaling pathway

Angiogenesis is a hallmark for cancer development because it is essential for cancer growth and provides the route for cancer cell migration (metastasis). Understanding the mechanism of angiogenesis and developing drugs that target the process has therefore been a major focus for research on cancer therapy. In this study, we screened 114 FDA-approved anti-cancer drugs for their effects on angiogenesis in the zebrafish. Among those with positive effects, we chose to focus on Ponatinib (AP24534; Iclusig^®) for further investigation. Ponatinib is an inhibitor of the tyrosine kinase BCR-ABL in chronic myeloid leukemia (CML), and its clinical trial has been approved by FDA for the treatment of the disease. In recent clinical trials, however, some side effects have been reported for Ponatinib, mostly on blood vessel disorders, raising the possibility that this drug may influence angiogenesis. In this study, we demonstrated that Ponatinib was able to suppress the formation of intersegmental vessels (ISV) and subintestinal vessels (SIV) in the zebrafish larvae. The anti-angiogenic effect of Ponatinib was further validated by other bioassays in human umbilical vein endothelial cells (HUVECs), including cell proliferation and migration, tube formation, and wound healing. Further experiments showed that Ponatinib inhibited VEGF-induced VEGFR2 phosphorylation and its downstream signaling pathways including Akt/eNOS/NO pathway and MAPK pathways (ERK and p38MAPK). Taken together, these results suggest that inhibition of VEGF signaling at its receptor level and downstream pathways may likely be responsible for the antiangiogenic activity of Ponatinib.

Protective Effects of Protocatechuic Acid on Seizure-Induced Neuronal Death

Protocatechuic acid (PCA) is a type of phenolic acid found in green tea and has been shown to have potent antioxidant and anti-inflammatory properties. However, the effect of PCA on pilocarpine seizure-induced neuronal death in the hippocampus has not been evaluated. In the present study, we investigated the potential therapeutic effects of PCA on seizure-induced brain injury. Epileptic seizure was induced by intraperitoneal (i.p.) injection of pilocarpine (25 mg/kg) in adult male rats, and PCA (30 mg/kg) was injected into the intraperitoneal space for three consecutive days after the seizure. Neuronal injury and oxidative stress were evaluated three days after a seizure. To confirm whether PCA increases neuronal survival and reduced oxidative injury in the hippocampus, we performed Fluoro-Jade-B (FJB) staining to detect neuronal death and 4-hydroxynonenal (4HNE) staining to detect oxidative stress after the seizure. In the present study, we found that, compared to the seizure vehicle-treated group, PCA administration reduced neuronal death and oxidative stress in the hippocampus. To verify whether a decrease of neuronal death by PCA treatment was due to reduced glutathione (GSH) concentration, we measured glutathione with N-ethylmaleimide (GS-NEM) levels in hippocampal neurons. A seizure-induced reduction in the hippocampal neuronal GSH concentration was preserved by PCA treatment. We also examined whether microglia activation was affected by the PCA treatment after a seizure, using CD11b staining. Here, we found that seizure-induced microglia activation was significantly reduced by the PCA treatment. Therefore, the present study demonstrates that PCA deserves further investigation as a therapeutic agent for reducing hippocampal neuronal death after epileptic seizures.

Chrysin: Sources, beneficial pharmacological activities, and molecular mechanism of action

In recent years, public and scientific interest in plant flavonoids has tremendously increased because of their postulated health benefits. This review was mainly focuses on the flavone chrysin (5,7-dihydroxyflavone), which occurs naturally in many plants, honey, and propolis. A number of in vitro and in vivo studies have revealed the therapeutic effects of chrysin against various diseases. In general, chrysin exhibits many biological activities and pharmacological effects, including antioxidant, anti-inflammatory, anticancer, and antiviral activities. Moreover, many studies have reported on the bioavailability of chrysin. Because of its compromised bioavailability and enhanced protein stability, chrysin solid lipid nanoparticle (SLN) synthesis avoids proteolytic degradation and sustained release of drug delivery. To clarify the mechanism of action of chrysin, researchers have investigated the structural binding relationship of chrysin through the docking computation method.

Comparative Analysis of Tocopherol Biosynthesis Genes and Its Transcriptional Regulation in Soybean Seeds

Tocopherols composed of four isoforms (α, β, γ, and δ) and its biosynthesis comprises of three pathways: methylerythritol 4-phosphate (MEP), shikimate (SK) and tocopherol-core pathways regulated by 25 enzymes. To understand pathway regulatory mechanism at transcriptional level, gene expression profile of tocopherol-biosynthesis genes in two soybean genotypes was carried out, the results showed significantly differential expression of 5 genes: 1-deoxy-d-xylulose-5-P-reductoisomerase (DXR), geranyl geranyl reductase (GGDR) from MEP, arogenate dehydrogenase (TyrA), tyrosine aminotransferase (TAT) from SK and γ-tocopherol methyl transferase 3 (γ-TMT3) from tocopherol-core pathways. Expression data were further analyzed for total tocopherol (T-toc) and α-tocopherol (α-toc) content by coregulation network and gene clustering approaches, the results showed least and strong association of γ-TMT3/tocopherol cyclase (TC) and DXR/DXS, respectively, with gene clusters of tocopherol biosynthesis suggested the specific role of γ-TMT3/TC in determining tocopherol accumulation and intricacy of DXR/DXS genes in coordinating precursor pathways toward tocopherol biosynthesis in soybean seeds. Thus, the present study provides insight into the major role of these genes regulating the tocopherol synthesis in soybean seeds.

The Medicinal Chemistry of Natural and Semisynthetic Compounds against Parkinson's and Huntington's Diseases

Among the diseases affecting the central nervous system (CNS), neurodegenerations attract the interest of both the clinician and the medicinal chemist. The increasing average age of population, the growing number of patients, and the lack of long-term effective remedies push ahead the quest for novel tools against this class of pathologies. We present a review on the state of the art of the molecules (or combination of molecules) of natural origin that are currently under study against two well-defined pathologies: Parkinson's disease (PD) and Huntington's disease (HD). Nowadays, very few tools are available for preventing or counteracting the progression of such diseases. Two major parameters were considered for the preparation of this review: particular attention was reserved to these research works presenting well-defined molecular mechanisms for the studied compounds, and where available, papers reporting in vivo data were preferred. A literature search for peer-reviewed articles using PubMed, Scopus, and Reaxys databases was performed, exploiting different keywords and logical operators: 91 papers were considered (preferentially published after 2015). The review presents a brief overview on the etiology of the studied neurodegenerations and the current treatments, followed by a detailed discussion of the natural and semisynthetic compounds dividing them in different paragraphs considering their several mechanisms of action.

Live or let die: Neuroprotective and anti-cancer effects of nutraceutical antioxidants

Diet sources are closely involved in the pathogenesis of diverse neuropsychiatric disorders and cancers, in addition to inherited factors. Currently, natural products or nutraceuticals (commonly called medical foods) are increasingly employed for adjunctive therapy of these patients. However, the potential molecular mechanisms of the nutrient efficacy remain elusive. In this review, we summarized the neuroprotective and anti-cancer mechanisms of nutraceuticals. It was concluded that the nutraceuticals exerted neuroprotection and suppressed tumor growth possibly through the differential modulations of redox homeostasis. In addition, the balance between reactive oxygen species (ROS) production and ROS elimination was manipulated by multiple molecular mechanisms, including cell signaling pathways, inflammation, transcriptional regulation and epigenetic modulation, which were involved in the therapeutic potential of nutraceutical antioxidants against neurological diseases and cancers. We specifically proposed that ROS scavenging was integral in the neuroprotective potential of nutraceuticals, while alternation of ROS level (either increase or decrease) or disruption of redox homeostasis (ROS addiction) constituted the anti-cancer property of these compounds. We also hypothesized that ROS-associated ferroptosis, a novel type of lipid ROS-dependent regulatory cell death, was likely to be a critical mechanism for the nutraceutical antioxidants. Targeting ferroptosis is advantageous to develop new nutraceuticals with more effective and lower adverse reactions for curing patients with neuropsychiatric diseases or carcinomas.

The Mechanisms of Traditional Chinese Medicine Underlying the Prevention and Treatment of Parkinson's Disease

Parkinson's disease (PD), characterized with bradykinesia, static tremor, rigidity and disturbances in balance, is the second most common neurodegenerative disorder. Along with the largely aging population in the world, the incidence is increasing year by year, which imposes the negative impacts on patients, their families and the whole society. Traditional Chinese medicine (TCM) has a positive prospect for the prevention and cure of PD due to its advantages of less side effects and multi-target effects. At present, the pathogenesis of PD is not yet fully discovered. This paper elaborates the mechanisms of TCM underlying the prevention and treatment of PD with regards to the inhibition of oxidative stress, the regulation of mitochondrial dysfunction, the reduction of toxic excitatory amino acids (EAA), the inhibition of neuroinflammation, the inhibition of neuronal apoptosis, and the inhibition of abnormal protein aggregation.

Pharmacological effects of protocatechuic acid and its therapeutic potential in neurodegenerative diseases: Review on the basis of in vitro and in vivo studies in rodents and humans

Protocatechuic acid has very promising properties potentially useful in the inhibition of neurodegenerative diseases progression. It is the main metabolite of the complex polyphenolic compounds and is believed to be responsible for beneficial effects associated with consumption of the food products rich in polyphenols. Protocatechuic acid is present in the circulation significantly longer and at higher concentrations than parent compounds and easily crosses the blood brain barrier. The aim of the following paper is to provide an extensive and actual report on protocatechuic acid and its pharmacological potential in prevention and/or treatment of neurodegenerative diseases in humans based on existing data from both in vitro and in vivo studies. Experimental studies strongly support the role of protocatechuic acid in the prevention of neurodegenerative processes, including Alzheimer's and Parkinson's diseases, due to its favorable influence on processes underlying cognitive and behavioral impairment, namely accumulation of the β-amyloid plaques in brain tissues, hyperphosphorylation of tau protein in neurons, excessive formation of reactive oxygen species and neuroinflammation. There is a growing evidence that protocatechuic acid may become in the future efficacious and safe substance that protects against neurodegenerative disorders.

The Neuroprotective Effects of Phenolic Acids: Molecular Mechanism of Action

The neuroprotective role of phenolic acids from food has previously been reported by many authors. In this review, the role of phenolic acids in ameliorating depression, ischemia/reperfusion injury, neuroinflammation, apoptosis, glutamate-induced toxicity, epilepsy, imbalance after traumatic brain injury, hyperinsulinemia-induced memory impairment, hearing and vision disturbances, Parkinson’s disease, Huntington’s disease, anti-amyotrophic lateral sclerosis, Chagas disease and other less distributed diseases is discussed. This review covers the in vitro, ex vivo and in vivo studies concerning the prevention and treatment of neurological disorders (on the biochemical and gene expression levels) by phenolic acids.

Attenuation of acute restraint stress-induced depressive like behavior and hippocampal alterations with protocatechuic acid treatment in mice

Protocatechuic acid ethyl ester (PCA), a phenolic compound, exhibits neuroprotective effects through improving endogenous antioxidant enzymatic and nonezymatic system. Based on the role of oxidative stress in modulating depressive disorders and the relationship between neuroprotective and antioxidant potential of PCA, we studied if its antidepressant like effect is associated by modulation of cerebral cortex and hippocampal antioxidant alterations. Acute restraint stress (ARS) is known to induce depressive like behavior by neuronal oxidative damage in mice. Swiss albino mice subjected to ARS exhibited an increased immobility time in forced swim test, elevated serum corticosterone and produced oxidative stress dependent alterations in cerebral cortex and hippocampus mainly increased thiobarbituric acid reactive substances and reduced catalase (CAT), superoxide dismutase (SOD) activity. Treatment with PCA was able to prevent stress induced immobility time in forced swim test without altering locomotor activity in mice. Further, PCA treatment attenuated the elevation of serum corticosterone, lipid peroxidation and restored enzymatic antioxidants in cerebral cortex and hippocampus in ARS mice. Altogether, the experimental findings demonstrate the notion that PCA exhibit antidepressant like activity might be related, at least in part, to its capability of modulating antioxidant defense system and oxidative damage induced by ARS in cerebral cortex and hippocampus in mice and thus maintain the pro-/anti-oxidative homeostasis.

Chemical profiling analysis of Maca using UHPLC-ESI-Orbitrap MS coupled with UHPLC-ESI-QqQ MS and the neuroprotective study on its active ingredients

Lepidium meyenii (Maca), originated from Peru, has been cultivated widely in China as a popular health care food. However, the chemical and effective studies of Maca were less in-depth, which restricted its application seriously. To ensure the quality of Maca, a feasible and accurate strategy was established. One hundred and sixty compounds including 30 reference standards were identified in 6 fractions of methanol extract of Maca by UHPLC-ESI-Orbitrap MS. Among them, 15 representative active compounds were simultaneously determined in 17 samples by UHPLC-ESI-QqQ MS. The results suggested that Maca from Yunnan province was the potential substitute for the one from Peru. Meanwhile, the neuroprotective effects of Maca were investigated. Three fractions and two pure compounds showed strong activities in the 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced zebrafish model. Among them, 80% methanol elution fraction (Fr5) showed significant neuroprotective activity, followed by 100% part (Fr6). The inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) was a possible mechanism of its neuroprotective effect.