Neuroprotective potential of biochanin-A and review of the molecular mechanisms involved.

Biochanin-A is a naturally occurring plant phytoestrogen, which mimics specific the agonistic activity of estrogens. Biochanin-A is known to possess numerous activities, including neuroprotective, anti-diabetic, hepatoprotective, anti-inflammatory, antioxidant, and antimicrobial activities, along with the anticancer activity. Neuroinflammation is thought to play a pivotal pathological role in neurodegenerative disease. Sustained neuroinflammatory processes lead to progressive neuronal damage in Parkinson's and Alzheimer's disease. Activation of PI3K/Akt cascade and inhibition of MAPK signaling cascade have been observed to be responsible for conferring protection against neuroinflammation in neurodegenerative diseases. An increased oxidative stress promotes neuronal apoptosis via potentiating the TLR-4/NF-κB and inhibiting PI3K/Akt signaling mediated increase in pro-apoptotic and decreases in antiapoptotic proteins. Various authors have explored biochanin-A's neuroprotective effect by using various cell lines and animal models. Biochanin-A has been reported to mediate its neuroprotective via reducing the level of oxidants, inflammatory mediators, MAPK, TLR-4, NF-κB, NADPH oxidase, AchE, COX-2 and iNOS. Whereas, it has been observed to increase the level of anti-oxidants, along with phosphorylation of PI3K and Akt proteins. The current review has been designed to provide insights into the neuroprotective effect of biochanin-A and possible signaling pathways leading to protection against neuroinflammation and apoptosis in the central nervous system. This review will be helpful in guiding future researchers to further explore biochanin A at a mechanistic level to obtain useful lead molecules.

Exploring the possible mechanism involved in the anti-nociceptive effect of ß-sitosterol: modulation of oxidative stress, nitric oxide and IL-6.

Β-sitosterol is a phytosterol, documented to possess various activities including protection against inflammation, diabetes and Alzheimer's disease. The current investigation was designed to explore the analgesic potential of ß-sitosterol and the possible molecular mechanism involved in the observed effect. ß-sitosterol was administered at varying doses of 10, 20, and 40 mg/kg before subjecting the mice to acetic acid and formalin challenges. The number of writhings in acetic acid and the number of flinchings and foot tappings were quantified in the formalin test. For mechanistic studies, substance P (cyclooxygenase-2 (COX-2) stimulator) and L-Nitro arginine methyl ester (L-NAME) (nitric oxide synthetases (NOS) inhibitor) and L-arginine (nitric oxide precursor) were administered before ß-sitosterol treatment. ß-sitosterol (10, 20, 40 mg/kg) treatment significantly reduced acetic acid-induced writhings and ameliorated the formalin-induced inflammatory phase dose-dependently. Whereas, 40 mg/kg dose of ß-sitosterol abrogated the formalin-induced neurogenic phase. Substance-P abrogated the effect of ß-sitosterol in both neurogenic and inflammatory phases. Whereas, L-arginine only abrogated the inflammatory phase. In biochemical analysis, ß-sitosterol treatment reduced the level of interleukin-6 (IL-6), thiobarbituric acid reactive substances (TBARS) and increased the level of reduced glutathione (GSH). Furthermore, L-arginine and substance-P abrogated the GSH increasing and TBARS lowering effect of ß-sitosterol (40 mg/kg). Overall, the current study delineated that ß-sitosterol may induce an anti-nociceptive effect via inhibiting the IL-6, oxidative stress, cyclo-oxygenase and nitric oxide.

Daphnetin, a natural coumarin averts reserpine-induced fibromyalgia in mice: modulation of MAO-A.

Fibromyalgia is a common, chronic, and generalized pain syndrome that is often associated with comorbid depression. The etiology of fibromyalgia is complex; most researchers have documented that the hallmark symptoms are due to the central nervous system's abnormal functioning. Neurotransmitters such as serotonin, norepinephrine, and glutamate, have been reported to be key regulators of fibromyalgia syndrome. Daphnetin is a 7, 8 dihydroxy coumarin widely distributed in Thymelaeaceae family plants, possessing various activities such as anti-arthritic, anti-tumor, anti-malarial, and anti-parasitic. The present study was designed to explore the potential of daphnetin against reserpine-induced fibromyalgia in mice. In mice, a fibromyalgia-like state was achieved by injecting reserpine (0.5 mg/kg, s.c) continuously for 3 days. All behavioral tests were conducted on the 4th and 6th day of experimentation. Reserpine administration significantly increased the mechanical hypersensitivity in electronic von Frey (eVF) and pressure application measurement (PAM) tests. It also increased the immobility period and time to reach the platform in force swim test (FST) and Morris water maze (MWM) test, respectively. In the biochemical analysis, reserpine treatment upregulated the monoamine oxidase-A (MAO-A) activity and level of glutamate, tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1ß), and thiobarbituric acid reactive substances (TBARS). Whereas, it decreased the level of glutathione (GSH), dopamine, serotonin, and norepinephrine. Daphnetin pretreatment attenuated the behavioral and biochemical changes induced by reserpine. Thus, the current investigation results delineate that daphnetin might exert its protective effect by inhibiting inflammatory stress and MAO-A-mediated neurotransmitter depletion and oxidative stress.

1H-1,2,3-triazole grafted tacrine-chalcone conjugates as potential cholinesterase inhibitors with the evaluation of their behavioral tests and oxidative stress in mice brain cells.

The present paper explicates the synthesis of 1H-1,2,3-triazole tethered tacrine-chalcone conjugates and evaluation of their AChE and BuChE inhibitory activity. In-vitroAChE inhibition assay revealed three compounds, 9h, 9i, and 11f, being more potent than the standard drug tacrine and further evaluated against butyrylcholinesterase. The present study was extended to investigate the anti-amnestic effect of promising compoundson scopolamine-induced behavioral and neurochemical changes in mice. Inclined plane model and Elevated plus-maze model were performed to assess general limb motor activity and anxiety-like behavior, respectively, in mice pre-treated with scopolamine. Oxidative stress parameters reduced glutathione contents (GSH) and lipid peroxidation products (TBARS) in the brain homogenates as estimated using ex-vivo studies. Furthermore, molecular docking studies were performed for the potent compounds to decipher the mechanism of observed activities.

Skimmetin/osthole mitigates pain-depression dyad via inhibiting inflammatory and oxidative stress-mediated neurotransmitter dysregulation.

Pain and depression are often co-existing pathological states that promote mutual severity resulting in limited efficacy of current treatment strategies. Thus, there is a need to develop an efficacious alternate treatment regimen for pain-depression dyad. Skimmetin and osthole are molecules of natural origin that have been explored for an anti-hyperglycemic, anti-bacterial, anti-fungal, and anti-diabetic activities in preclinical studies. in animal models. The current study has been designed to explore the beneficial effect of skimmetin/osthole in reserpine-induced pain-depression dyad in mice. Female Swiss albino mice (n = 6) were challenged with reserpine (0.5 mg/kg s.c.) for the first 3 days to induce a pain-depression dyad-like state. Skimmetin (10 mg/kg i.p.) and osthole (10 mg/kg i.p.) were administered for 5 days consecutively, starting from the first day of study. Reserpine treatment significantly reduced the pain threshold in the pressure application measurement (PAM) and electronic von frey (eVF) test. In forced swim test (FST) and Morris water maze (MWM) test mice displayed an increased immobility time and latency to reach platform respectively. Biochemical results showed an increased level of TNF-α, IL-1ß, TBARS, glutamate, and reduced level of GSH, norepinephrine, and serotonin in the reserpine treated group. Reserpine treatment also increased brain MAO-A activity. Skimmetin/osthole treatment was found to attenuate the behavioral and biochemical alterations induced by reserpine. The results of the current investigation delineated that skimmetin/osthole may exert anti-nociceptive, anti-depressant, and improved cognition via inhibiting inflammatory and oxidative stress-mediated neurotransmitter dysregulation.

Understanding the phytochemistry and molecular insights to the pharmacology of Angelica archangelica L. (garden angelica) and its bioactive components.

Plant-derived molecules have enduring usefulness in treating diseases, and herbal drugs have emerged as a vital component of global therapeutic demand. Angelica archangelica L. (A. archangelica), commonly known as garden angelica, is an aromatic food plant used in culinary procedures as a flavoring agent. In the traditional medicine system, it is regarded as an "Angel plant" due to its miraculous curative power. This review aims to provide a comprehensive summary of the plant's taxonomic profile, ethnopharmacology, Phytochemistry, and pharmacological activities. Various in vivo and in vitro experiments have validated that the plant possesses broad pharmacological potential. The biological activities attributed to the plant include anti-anxiety activity, anti-convulsant activity, cognition enhancer, antiviral activity, cholinesterase inhibitory potential, antiinflammatory activity, gastroprotective activity, and radioprotective activity. The beneficial effects of the plant are credited to its bioactive components, that is, coumarins and volatile oils. The review summarizes the pharmacological activities of crude extract and its bioactive fractions and has also explored their target-oriented effects. This review will be of value in undertaking further investigations on the plant with regard to exploring mechanism-based pharmacological approaches on A. archangelica.

Protective Effect of Esculetin, Natural Coumarin in Mice Model of Fibromyalgia: Targeting Pro-Inflammatory Cytokines and MAO-A.

Fibromyalgia is a refractory syndrome characterized by chronic wayward pain and complex co-morbid psychological trepidation. The current treatments have a limited role and proper clinical benefits are far from satisfactory. Naturally occurring coumarins such as osthole are known to have analgesic and anti-inflammatory activities. Therefore, the current investigation was designed to explore the potential of natural coumarin esculetin (2.5, 5, and 10 mg/kg) in mitigating reserpine-induced fibromyalgia in Swiss albino mice. Esculetin is a 6,7 dihydroxy-coumarin obtained from various plant sources such as Aesculus hippocastanum L, Ceratostigma willmottianum, Citrus limonia, etc. Reserpine (0.5 mg/kg/day s.c.) treatment for first 3 days, significantly altered the behavior of mice as evidenced by reduced paw withdrawal threshold in pressure application measurement (PAM) test and electronic von-Frey (eVF) test, increased immobility time in forced swim test (FST), increased latency to reach the platform in Morris water maze (MWM) test and reduced number of square crossed in the open field test (OFT). These behavioral deficits with reserpine treatment were integrated with a reduced level of serotonin (5-HT), reduced glutathione (GSH), along with an increase in monoamine oxidase-A (MAO-A) activity, pro-inflammatory cytokines (IL-1ß, TNF-α), thiobarbituric acid reactive substances (TBARS) and glutamate level. Esculetin (10 mg/kg/day i.p) treatment for 5 days, significantly abrogated reserpine induced behavioral and biochemical alterations. Whereas, no significant improvement was observed with lower doses of esculetin i.e. 2.5 and 5 mg/kg.

Modification of the lead molecule: Tryptophan and piperidine appended triazines reversing inflammation and hyeperalgesia in rats.

The structural optimization of the molecules making them to fit into the active site pocket of COX-2 occupying the same space as covered by the natural substrate arachidonic acid helped in the emergence of compound 10 as an efficacious anti-inflammatory agent. Selective for COX-2 over COX-1, compound 10 exhibited IC50 0.02 µM for COX-2 and reversed acetic acid induced inflammation in rats by 73% when used at 10 mg kg-1 dose and the same dose of the compound also rescued the animals from inflammatory phase of formalin induced hyperalgesia. As evidenced by the results of molecular modeling studies supported by the nuclear Overhauser enhancement data, the appropriate geometry of the molecule in the active site pocket of COX-2 contributing to its H-bond/hydrophobic interactions with Ser530, Trp387 and Tyr385 seems responsible for the enzyme inhibitory activity of the compound.

Anti-nociceptive and anti-inflammatory effect of imperatorin: evidences for involvement of COX-2, iNOS, NFκB and inflammatory cytokines.

Aim: The objective of the current investigation was to explore the analgesic effect of naturally occurring furanocoumarin, imperatorin and the involvement of inducible cyclooxygenase (COX-2), inducible nitric oxide synthase (iNOS), NFκB and cytokines in the observed effect.Materials and methods: Anti-nociceptive effect was explored by inducing chemical hyperalgesia using acetic acid and formalin in mice. ED50 of imperatorin was calculated in acetic acid model. Modulation of cyclooxygenase and nitric oxide pathway by imperatorin was examined by stimulator/precursor challenge with substance P and L-arginine, respectively and quantification of COX-2, iNOS and NFκB expression by immunohistochemical analysis in spinal tissues. Involvement of inflammatory cytokines TNF-α and IL-1ß was investigated using LPS challenge and subsequent ELISA analysis of these inflammatory mediators in serum. Carrageenan inflicted paw edema was employed to explore the anti-inflammatory activity of imperatorin.Results: A significant reduction in the nociceptive behaviour was observed with imperatorin treatment in acetic acid and formalin test. ED50 of imperatorin was found to be 4.53 mg/kg. Pre-treatment with substance P and L-arginine significantly attenuated the anti-nociceptive activity of imperatorin in formalin test. Immunohistochemical findings revealed marked decrease in spinal COX-2, iNOS and NFκB expression. Imperatorin administration significantly reduced LPS induced rise in level of TNF-α and IL-1ß dose dependently. In carrageenan-induced paw edema test, maximum possible anti-inflammatory effect of imperatorin was evident after 240 min of carrageenan administration.Conclusion: Current investigation revealed that anti-nociceptive and anti-inflammatory potential of imperatorin is probably mediated through the attenuation of COX-2, iNOS, NFκB activity and reduction in circulatory cytokines.

Possible Molecular Mediators Involved and Mechanistic Insight into Fibromyalgia and Associated Co-morbidities.

Fibromyalgia is a chronic complex syndrome of non-articulate origin characterized by musculoskeletal pain, painful tender points, sleep problems and co-morbidities including depression, migraine. The etiopathogenesis of fibromyalgia is complex, variable and remains inconclusive. The etiological factors that have been defined include stress, genetic predisposition and environmental components. As per the reports of the American College of Rheumatology (ACR) the prevalence of fibromyalgia varies from 2 to 22% among the general population with poor diagnostic features primarily pain. Fibromyalgia encompasses a spectrum of co-morbid conditions with multifarious pathogenesis. The highly prevalent manifestations of fibromyalgia include heterogeneous pain and aches. Biochemical and neurobiological elements of fibromyalgia include neurotransmitters, hypothalamic pituitary adrenal axis (HPA axis), inflammatory cytokines, monoaminergic pathway, opioid peptides, sex hormones, nerve growth factor (NGF) and local free radical insult. An imbalance in the serotonergic system is the major underlying etiological factor that has been explored most widely. Owing to complex interplay of diverse pathophysiological pathways, overlapping co-morbidities such as depression have been clinically observed. Therapeutic management of fibromyalgia involves both non pharmacological and pharmacological measures. The current review presents various dysregulations and their association with symptoms of fibromyalgia along with their underlying neurobiological aspects.

Osthole ameliorates neurogenic and inflammatory hyperalgesia by modulation of iNOS, COX-2, and inflammatory cytokines in mice.

BACKGROUND: Osthole is a bioactive component reported in medicinal plants such as Angelica pubescens and Cnidium monnieri, known for analgesic activity. However, the toxicity, median effective dose (ED50), and dual modulation of nitric oxide and cyclooxygenase pathways along with inflammatory cytokines of osthole are yet to be determined. METHODS: The animals (mice) were assessed for general behaviour and mortality in varying doses (50, 300, and 2000 mg kg-1) of osthole for acute toxicity over 14 days. The analgesic activity was investigated using acetic acid and formalin-induced hyperalgesia, and anti-inflammatory activity was explored in carrageenan-induced paw oedema. ED50 of osthole was calculated using Design Expert software. Involvement of nitric oxide and cyclooxygenase pathways was investigated by agonist challenges with L-arginine and substance P, respectively. The expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) was determined in spinal sections by immunohistochemical analysis. Lipopolysaccharide (LPS) challenge was used to assess in vivo effect on inflammatory cytokines (TNFα and IL-6). RESULTS: Acute toxicity studies revealed no behavioural abnormality or mortality on osthole treatment and unremarkable histological findings. Osthole was found to significantly decrease acetic acid and formalin-induced hyperalgesia (ED50 = 5.43 mg kg-1) and carrageenan-induced paw oedema with no toxicity symptoms. Osthole produced a marked decrease in iNOS and COX-2 expression as well as TNFα and IL-6. The findings corroborate to modulation of iNOS and COX-2 and inflammatory cytokines by osthole. This study provides promising insights and prospects for application of osthole in pain management.

Bergapten inhibits chemically induced nociceptive behavior and inflammation in mice by decreasing the expression of spinal PARP, iNOS, COX-2 and inflammatory cytokines.

In continuation with our previous studies on osthole, bergapten, a closely related furanocoumarin was investigated for its ameliorative effect on chemically induced neurogenic and inflammatory hyperalgesia and inflammation in mice. Chemical hyperalgesia and inflammation was induced by administration of formalin (intraplantar), acetic acid (intraperitoneal) and carrageenan (intraplantar) to different groups of animals. Pain responses were quantified and median effective dose (ED50) of bergapten was calculated. Lipopolysaccharide challenge was administered to study inflammatory cytokines which were analyzed in plasma using ELISA. The expression of poly ADP-ribose polymerase (PARP), cyclooxygenase (COX-2) and inducible nitric oxide synthase (iNOS) was quantified by immnofluorescence staining. Bergapten was found to ameliorate both neurogenic and inflammatory hyperalgesia precipitated by formalin, acetic acid induced writhing and carrageenan induced paw inflammation with ED50 dose of 2.96 mg/kg. Bergapten also significantly decreased the levels of TNF-α and IL-6 and the expression of PARP, COX-2 and iNOS in the spine. It is concluded that bergapten is an interesting molecule with significant analgesic and anti-inflammatory activity emanating through the modulation of multiple pain mediating pathways.

Mercurius solubilis attenuates scopolamine-induced memory deficits and enhances the motor coordination in mice.

AIM: The present study was designed to investigate the effect of mercurius solubilis (merc sol) on scopolamine induced memory deficits and motor coordination in mice. MATERIALS AND METHODS: Three different formulations of merc sol (30X, 200M, 1M) were screened for their in vitro antioxidant potential through DPPH (2, 2-diphenyl-1-picrylhydrazyl) and nitric oxide scavenging activity using response surface methodology. Memory impairment was induced by the administration of scopolamine (1mg/kg i.p.) for 3 days to mice and assessment of memory acquisition and retention was done using Morris water maze test, passive avoidance test, elevated plus maze test, light and dark box test, motor coordination was evaluated using rotarod test and inclined plan test. The involvement of ion channels and nitric oxide pathway in the observed effect of merc sol was elucidated by administration of veratrine (0.125 µg/kg, i.p.), A23187 (20 µg/kg, i.p.), L- arginine (40 mg/kg, i.p.), aminoguanidine (50 mg/kg, i.p.) 30 min prior to merc sol. Acute toxicity studies were performed in accordance with the OECD (Organisation for Economic Co-operation and Development) guidelines. RESULTS: In vitro studies have revealed merc sol 30 X to have maximum free radical and nitric oxide scavenging activity. Administration of merc sol 30 X to mice significantly reduced scopolamine induced memory deficits and motor incoordination in all the performance tasks. The calcium ionophore, A23187 significantly altered the effect of merc sol in mice. No major signs of toxicity were observed. CONCLUSION: Merc sol has antiamnesic effect in scopolamine induced deficits and motor coordination in mice.

Explicit role of peroxisome proliferator-activated receptor gamma in gallic acid-mediated protection against ischemia-reperfusion-induced acute kidney injury in rats.

BACKGROUND: Gallic acid is a polyphenolic compound and is reported to be renoprotective because of its antioxidant activity in various preclinical studies. Gallic acid has been reported to activate peroxisome proliferator-activated receptor gamma (PPAR-γ) in vitro. However, the relevance of the interplay between gallic acid and PPAR-γ in various pathologic conditions is yet to be established in vivo. The present study investigated the protective role of gallic acid against ischemia-reperfusion-induced acute kidney injury (AKI) and the possible involvement of PPAR-γ in gallic acid-mediated renoprotection. MATERIALS AND METHODS: The AKI was induced in rats through bilateral clamping of renal arteries for 40 min followed by reperfusion for 24 h. The AKI was assessed by the quantification of creatinine clearance, blood urea nitrogen, uric acid, potassium level, fractional excretion of sodium, and urinary microproteins. The oxidative stress in renal tissues was quantified in terms of myeloperoxidase activity, thiobarbituric acid reactive substances, superoxide anion generation, and reduced glutathione level. The histopathologic changes in renal tissues were assessed by hemotoxylin and eosin staining. The rats were administered gallic acid (50, 100, and 200 mg/kg) orally for 7 d before subjecting them to AKI. RESULTS: The renal ischemia-reperfusion induced significant changes in plasma, urinary, and tissue parameters. The administration of gallic acid at three dose levels offered a significant protection against renal ischemia-reperfusion-induced AKI. The prior treatment with PPAR-γ antagonist, bisphenol A diglycidyl ether, significantly abolished the renoprotective effect of gallic acid that confirms the involvement of PPAR-γ in gallic acid-mediated renoprotection. CONCLUSIONS: It is concluded that the activation of PPAR-γ significantly contributes toward gallic acid-mediated protection against ischemia-reperfusion-induced AKI.

Role of progesterone in melatonin-mediated protection against acute kidney injury.

BACKGROUND: Melatonin is released by pineal gland and maintains circadian rhythm in the body. It has been reported as renoprotective agent because of its antioxidant property. Recently, a cross talk between progesterone and melatonin has been observed in various preclinical studies. The present study investigated the involvement of progesterone receptors in melatonin-mediated protection against ischemia reperfusion induced acute kidney injury (AKI) in rats. MATERIALS AND METHODS: The rats were subjected to bilateral renal ischemia for 40 min followed by reperfusion for 24 h to induce AKI. The AKI was assessed by measuring creatinine clearance, serum urea, uric acid level, potassium level, fractional excretion of sodium, lactate dehydrogenase activity, and microproteinuria. The oxidative stress in renal tissues was assessed by quantification of myeloperoxidase activity, thiobarbituric acid reactive substances, superoxide anion generation, reduced glutathione level, and catalase activity. The hematoxylin-eosin staining was carried out to observe histopathologic changes in renal tissues. The melatonin (4 and 10 mg/kg, intraperitoneally) and progesterone receptor antagonist mifepristone (5 mg/kg, intraperitoneally) were used in the present study. RESULTS: The renal ischemia reperfusion induced AKI as indicated by significant change in serum, urinary, and tissue parameters that was ameliorated by prior treatment with melatonin. No significant difference in serum progesterone level was observed between various groups used in the present study. The prior administration of mifepristone abolished melatonin-mediated protection against AKI. CONCLUSIONS: It is concluded that melatonin treatment affords protection against ischemia reperfusion induced AKI. Moreover, progesterone receptors are essentially involved in mediating protective role of melatonin against AKI in rats.

Rationally designed hybrid molecules with appreciable COX-2 inhibitory and anti-nociceptive activities.

Six molecules were obtained by the combination of three biologically and medicinally significant moieties-indole, chrysin and pyrazole. Bio-evaluation of these hybrid molecules showed significant inhibition of COX-2 enzymatic activity over that of COX-1 and appreciable anti-nociceptive activity, checked at swiss albino mice.

Signaling Pathways Involved in the Neuroprotective Effect of Osthole: Evidence and Mechanisms.

Neurodegenerative diseases constitute a major threat to human health and are usually accompanied by progressive structural and functional loss of neurons. Abnormalities in synaptic plasticity are involved in neurodegenerative disorders. Aberrant cell signaling cascades play a predominant role in the initiation, progress as well as in the severity of these ailments. Notch signaling is a pivotal role in the maintenance of neural stem cells and also participates in neurogenesis. PI3k/Akt cascade regulates different biological processes including cell proliferation, apoptosis, and metabolism. It regulates neurotoxicity and mediates the survival of neurons. Moreover, the activated BDNF/TrkB cascade is involved in promoting the transcription of genes responsible for cell survival and neurogenesis. Despite significant progress made in delineating the underlying pathological mechanisms involved and derangements in cellular metabolic promenades implicated in these diseases, satisfactory strategies for the clinical management of these ailments are yet to be achieved. Therefore, the molecules targeting these cell signaling cascades may emerge as useful leads in developing newer management strategies. Osthole is an important ingredient of traditional Chinese medicinal plants, often found in various plants of the Apiaceae family and has been observed to target these aforementioned mediators. Until now, no review has been aimed to discuss the possible molecular signaling cascades involved in osthole-mediated neuroprotection at one platform. The current review aimed to explore the interplay of various mediators and the modulation of the different molecular signaling cascades in osthole-mediated neuroprotection. This review could open new insights into research involving diseases of neuronal origin, especially the effect on neurodegeneration, neurogenesis, and synaptic plasticity. The articles gathered to compose the current review were extracted by using the PubMed, Scopus, Science Direct, and Web of Science databases. A methodical approach was used to integrate and discuss all published original reports describing the modulation of different mediators by osthole to confer neuroprotection at one platform to provide possible molecular pathways. Based on the inclusion and exclusion criteria, 32 articles were included in the systematic review. Moreover, literature evidence was also used to construct the biosynthetic pathway of osthole. The current review reveals that osthole promotes neurogenesis and neuronal functioning via stimulation of Notch, BDNF/Trk, and P13k/Akt signaling pathways. It upregulates the expression of various proteins, such as BDNF, TrkB, CREB, Nrf-2, P13k, and Akt. Activation of Wnt by osthole, in turn, regulates downstream GSK-1ß to inhibit tau phosphorylation and ß-catenin degradation to prevent neuronal apoptosis. The activation of Wnt and inhibition of oxidative stress, Aß, and GSK-3ß mediated ß-catenin degradation by osthole might also be involved in mediating the protection against neurodegenerative diseases. Furthermore, it also inhibits neuroinflammation by suppressing MAPK/NF-κB-mediated transcription of genes involved in the generation of inflammatory cytokines and NLRP-3 inflammasomes. This review delineates the various underlying signaling pathways involved in mediating the neuroprotective effect of osthole. Modulation of Notch, BDNF/Trk, MAPK/NF-κB, and P13k/Akt signaling pathways by osthole confers protection against neurodegenerative diseases. The preclinical effects of osthole suggest that it could be a valuable molecule in inspiring the development of new drugs for the management of neurodegenerative diseases and demands clinical studies to explore its potential. An effort has been made to unify the varied mechanisms and target sites involved in the neuroprotective effect of osthole. The comprehensive description of the molecular pathways in the present work reflects its originality and thoroughness. The reviewed literature findings may be extrapolated to suggest the role of othole as a "biological response modifier" which contributes to neuroprotection through kinase modulatory, immunomodulatory, and anti-oxidative activity, which is documented even at lower doses. The current review attempts to emphasize the gaps in the existing literature which can be explored in the future.

Neuroprotective potential of formononetin, a naturally occurring isoflavone phytoestrogen.

The increased prevalence of neurological illnesses is a burgeoning challenge to the public healthcare system and presents greater financial pressure. Formononetin, an O-methylated isoflavone, has gained a lot of attention due to its neuroprotective potential explored in several investigations. Formononetin is widely found in legumes and several types of clovers including Trifolium pratense L., Astragalus membranaceus, Sophora tomentosa, etc. Formononetin modulates various endogenous mediators to confer neuroprotection. It prevents RAGE activation that results in the inhibition of neuronal damage via downregulating the level of ROS and proinflammatory cytokines. Furthermore, formononetin also increases the expression of ADAM-10, which affects the pathology of neurodegenerative disease by lowering tau phosphorylation, maintaining synaptic plasticity, and boosting hippocampus neurogenesis. Besides these, formononetin also increases the expression of antioxidants, Nrf-2, PI3K, ApoJ, and LRP1. Whereas, reduces the expression of p65-NF-κB and proinflammatory cytokines. It also inhibits the deposition of Aß and MAO-B activity. An inhibition of Aß/RAGE-induced activation of MAPK and NOX governs the protection elicited by formononetin against inflammatory and oxidative stress-induced neuronal damage. Besides this, PI3K/Akt and ER-α-mediated activation of ADAM10, ApoJ/LRP1-mediated clearance of Aß, and MAO-B inhibition-mediated preservation of dopaminergic neurons integrity are the major modulations produced by formononetin. This review covers the biosynthesis of formononetin and key molecular pathways modulated by formononetin to confer neuroprotection.

Small Peptides Targeting BACE-1, AChE, and A-ß Reversing Scopolamine-Induced Memory Impairment: A Multitarget Approach against Alzheimer's Disease.

Based on the biochemical understanding of Alzheimer's disease, here, we report the design, synthesis, and biological screening of a series of compounds against this neuro-disorder. Adopting the multitarget approach, the catalytic processes of BACE-1 and AChE were targeted, and thereby, compounds 15, 22, 25, 26, 27, and 30 were identified with IC50 in the submicromolar range against these two enzymes. Further, compounds 15 and 25 displayed more than 50% inhibition of ß-amyloid aggregation. Implying their physiological use, the compounds exhibited appreciable biological membrane permeability as observed through the parallel artificial membrane permeability experiment. Supporting these results, treatment of the mice with the test compounds reversed their scopolamine-affected memory impairment, where the highest healing effect was seen in the case of compound 25. Overall, the combination of molecular modeling and experimental studies provided highly effective molecules against Alzheimer's disease.

Possible involvement of PPAR-γ in the anticonvulsant effect of Aegle marmelos (L.) Correa.

Aegle marmelos is well documented for antihyperglycemic effect and PPAR-γ activation has been suggested to be the molecular mechanism of its action. Also, the plant has been used in Ayurveda as a brain tonic and has been postulated to have antidepressant activities. The present study was designed to investigate the anticonvulsant effects of A. marmelos leaf extract (AME) in pentylenetetrazole and maximal electroshock induced convulsions; involvement of PPAR-γ, nitric oxide pathway and effect of chronic AME treatment on post-ictal depression. AME was administered at doses of 50, 100 and 200 mg kg(-1) in PTZ and MES model. Severity of convulsions was noted in both the models. Pretreatment with bisphenol A diglycidyl ether (BADGE) was used to study the involvement of PPAR-γ and L-arginine and N-nitro-L-arginine methyl ester hydrochloride (L-NAME) to study the involvement of nitric oxide (NO). Chronic treatment with AME interspersed with sub maximal doses of PTZ (50 mg kg(-1)) on every fifth day up to 15 days was given to study post-ictal depression using forced swimming and actophotometer. AME showed significant increase in the onset time and decrease in the duration of convulsions in PTZ and MES models dose dependently. In MES a dose of 100 mg kg(-1) had effect comparable to phenytoin. Pretreatment with BADGE and L-arginine reversed the protective effect while L-NAME did not alter the protective effect, thereby indicating possible involvement of PPAR-γ and inhibition of NO. Chronic AME treatment ameliorated the post-seizure depression significantly as evidenced by increase in the locomotor activity and decrease in the immobility time.