Effect of embelin against 3-nitropropionic acid-induced Huntington's disease in rats

Glycosylation of chrysin with β-d-glucose tetraacetate (LQFM280) enhances its in vitro and in vivo neuroprotective effects against the toxicity induced by 3-nitropropionic acid

Chrysin (CHR) is a naturally occurring flavonoid found in the human diet, recognized for its potential in preventing neurodegenerative diseases. However, its limited water solubility restricts its bioavailability and therapeutic applications. To address this issue and bolster the neuroprotective properties of CHR for potential nutraceutical or medicinal use, we investigated a novel compound, LQFM280, formed by conjugating CHR with β-d-glucose tetraacetate. We conducted both in vitro (using SH-SY5Y cells, mutant STHdhQ111/Q111 cells, and wild-type STHdhQ7/Q7 cells), and in vivo (mice) neurotoxicity experimental model induced by 3-nitropropionic acid, which mimic biological changes akin to Huntington's disease in humans. Compared to non-glycosylated CHR, LQFM280 showed superior in vitro effects in preventing neurotoxicity caused by increased mitochondrial vulnerability due to mutant huntingtin. In vivo findings demonstrated that LQFM280 has heightened efficacy in mitigating weight loss, memory and locomotor impairment, oxidative stress, and disruptions in the antioxidant defense system, as well as succinate dehydrogenase, and cholinesterase activities induced by 3-nitropropionic acid. These findings underscore the significant enhancement of chrysin's neuroprotective effects through glycosylation with β-d-glucose tetraacetate, positioning it as a promising candidate for use as a nutraceutical or food supplement to promote health benefits.

Trace Element Chromium-D-Phenylalanine Complex: Anti-Inflammatory and Antioxidant Insights from In Vivo and In Silico Studies

The biological significance of trace elements such as chromium extends beyond basic cellular functions, influencing key processes like inflammation and oxidative stress. In this study, we explore the anti-inflammatory and antioxidant potential of a trace element complex, Chromium-D-phenylalanine (Cr(D-Phe)₃), through in vivo and in silico approaches. Anti-inflammatory activity was assessed using a carrageenan-induced paw oedema model in rats, coupled with histopathological and biochemical analyses. The antioxidant effects of Cr(D-Phe)₃ were evaluated by measuring reduced glutathione (GSH), lipid peroxidation (LPO), and tumour necrosis factor-alpha (TNF-α) as a marker of inflammation. Furthermore, molecular docking and dynamics simulations were conducted to elucidate the compound's binding affinity and stability with cyclooxygenase enzymes. Cr(D-Phe)₃ exhibited significant anti-inflammatory activity, with the 40 μg/kg dose achieving 34.40% (p < 0.001) oedema inhibition, comparable to diclofenac sodium (42.40%). Treatment with Cr(D-Phe)₃ restored GSH levels (+ 62.10%, p < 0.001), reduced LPO (24.72%, p < 0.001), and lowered TNF-α (31.73%, p < 0.001) in carrageenan injected rats, demonstrating potent antioxidant and anti-inflammatory effects. Molecular docking revealed strong binding affinities between Cr(D-Phe)₃ and COX enzymes, suggesting its potential mechanism of action in modulating inflammatory pathways. This study highlights the potential of Cr(D-Phe)₃ as a chromium-based trace element complex with anti-inflammatory and antioxidant properties. These findings warrant further preclinical investigations to elucidate its full pharmacological potential and applications in managing inflammatory conditions.

Chromium-histidine complex enhances reproductive physiology and development in Drosophila melanogaster by modulating oxidative stress

The interaction of metal ions with biological systems plays a critical role in cellular functions, including oxidative stress regulation and metabolic health. This study aimed to explore the effects of the chromium-histidine complex [Cr(hist)3] on reproductive success, developmental processes, and oxidative stress defence in Drosophila melanogaster. Wild-type D. melanogaster flies were exposed to Cr(hist)3 at concentrations of 5, 10, 15, and 20 µg/ml, and physiological parameters-including fecundity, fertility, developmental timelines, and antioxidant enzyme activity-were measured. Our results indicate that Cr(hist)3 at 15 µg/ml optimally enhanced reproductive health and developmental efficiency. Specifically, fecundity and fertility increased by 15.6% and 15.5%, respectively, and egg-to-adult viability improved by 15.6% compared to controls. Developmental timelines were shortened, with larval and pupal periods reduced by 7.6% and 7.1%. Additionally, Cr(hist)3 treatment led to a significant downregulation of lipid peroxidation (MDA) by 17.54% and upregulation in antioxidant enzymes (catalase, glutathione-S-transferase, and superoxide dismutase), indicating improved cellular defence against oxidative damage. Flies treated with 15 µg/ml Cr(hist)33 also exhibited a 9.7% increase in lifespan. These findings suggest that Cr(hist)3 enhances reproductive success and developmental dynamics through oxidative stress regulation, highlighting its potential for applications in insect health and stress management. This study contributes to the understanding of metal ion interactions in biological systems and their physiological effects.

A Comprehensive Review of Therapeutic Compounds from Plants for Neurodegenerative Diseases

Neurodegenerative diseases (NDDs) comprise a large number of disorders that affects the structure and functions of the nervous system. The major cause of various neurodegenerative diseases includes protein aggregation, oxidative stress and inflammation. Over the last decade, there has been a gradual inclination in neurological research in order to find drugs that can prevent, slow down, or treat these diseases. The most common NDDs are Alzheimer's, Parkinson's, and Huntington's illnesses, which claims the lives of 6.8 million people worldwide each year and it is expected to rise by 7.1%. The focus on alternative medicine, particularly plant-based products, has grown significantly in recent years. Plants are considered as a good source of biologically active molecules and hence phytochemical screening of plants will pave way for the discovering new drugs. Neurodegeneration has been linked to oxidative stress, either as a direct cause or as a side effect of other variables. Therefore, it has been proposed that the use of antioxidants to combat cellular oxidative stress within the nervous system may be a viable therapeutic strategy for neurological illnesses. In order to prevent and treat NDDs, this review article covers the therapeutic compounds/ metabolites from plants with the neuroprotective role. However, these exhibit other beneficial molecular functions in addition to antioxidative activity, making them a potential application in the management or prevention of neurodegenerative disorders. Further, it gives the insights to the future researchers about considering the peptide based therapeutics through various mechanisms for delaying or curing neurodegenerative diseases.

Saroglitazar, a PPAR α/γ agonist alleviates 3-Nitropropionic acid induced neurotoxicity in rats: Unveiling the underlying mechanisms

Saroglitazar (SGZ), a peroxisomal proliferated activated receptor α/γ agonist showed neuroprotective effects in various neurodegenerative disorders like Alzheimer's and Parkinson's. However, no studies were performed on Huntington's, so the goal of the current study is to examine the effect of SGZ on Huntington's disease like symptoms induced by 3-Nitropropionic acid. In this protocol, twenty-four rats were divided into four groups, each group consisting of 6 animals. Group 1: The control group received 1 % CMC 10 mg/kg, p.o. for 14 days. Groups 2, 3, and 4 received 3-NP 15 mg/kg, i.p. from Day 1 to Day 7. Groups 3 and 4 received SGZ 5 mg/kg, p.o. and 10 mg/kg, p.o. respectively once daily from day 1 to day 14. Various behavioral tests like OFT, rotarod, hanging wire, narrow beam walk, MWM, and Y-maze were performed. On day-15, the animals were euthanised by cervical dislocation and brain sample were isolated for biochemical and histopathological analysis. Administration of 3-NP showed a significant decrease in motor coordination and cognitive function. Furthermore, 3-NP altered the activity of acetylcholinesterase, anti-oxidant enzymes, Nrf-2, NF-κB, BDNF, CREB levels, and histological features. However, treatment with SGZ showed ameliorative effects in the 3-NP induced neurotoxicity via PPAR α/γ pathway by reducing motor dysfunction, memory impairment, cholinesterase levels, oxidative stress, neuroinflammation. It also enhanced the levels of Nrf-2, BDNF, and CREB expression and improved histological features. In conclusion, treatment with Saroglitazar attenuated Huntington's disease-like symptoms in rats which are induced by 3-NP via activation of PPAR α/γ pathway.

Demystifying the Potential of Embelin-Loaded Nanoformulations: a Comprehensive Review

Phytoconstituent based therapies have the potential to reduce the adverse effects and enhance overall patient compliance for different diseased conditions. Embelin (EMB) is a natural compound extracted from Embelia ribes that has demonstrated high therapeutic potential, particularly as anti-inflammatory and anticancer therapeutic applications. However, its poor water solubility and low oral bioavailability limitations make it challenging to use in biomedical applications. Nanostructure-based novel formulations have shown the potential to improve physicochemical and biological characteristics of active pharmaceutical ingredients obtained from plants. Different nanoformulations that have been utilized to encapsulate/entrap EMB for various therapeutic applications are nanoliposomes, nanostructured lipid carriers, niosomes, polymeric nanoparticles, nanosuspensions, phytosomes, self nanoemulsifying drug delivery system, silver nanoparticles, microparticles, solid lipid nanoparticle, gold nanoparticles and nanomicelles. The common methods reported for the preparation of EMB nanoformulations are thin film hydration, nanoprecipitation, ethanol injection, emulsification followed by sonication. The size of nanoformulations ranged in between 50 and 345 nm. In this review, the mentioned EMB loaded nanocarriers are methodically discussed for size, shape, drug entrapment, zeta potential, in vitro release & permeation and in vivo studies. Potential of EMB with other drugs (dual drug approach) incorporated in nanocarriers are also discussed (physicochemical and preclinical characteristics). Patents related to EMB nanoformulations are also presented which showed the clinical translation of this bioactive for future utilization in different indications.

The Huntington's disease drug pipeline: a review of small molecules and their therapeutic targets

Huntington's disease (HD) is a progressive neurodegenerative condition resulting from a CAG repeat expansion in the huntingtin gene (HTT). Recent advancements in understanding HD's cellular and molecular pathways have paved the way for identifying various effective small-molecule candidates to treat the disorder. Two small molecules, Tetrabenazine and Deutetrabenazine, are approved for managing chorea associated with HD, and several others are under clinical trials. Notably, the field of small-molecule therapeutics targeting HD is rapidly progressing, and there is anticipation of their approval in the foreseeable future. This chapter provides a comprehensive overview of the emergence of small-molecule therapeutics in various stages of clinical development for HD therapy. The emphasis is placed on detailing their structural design, therapeutic effects, and specific mechanisms of action. Additionally, exploring key drivers implicated in HD pathogenesis offers valuable insights, as a foundational principle for designing prospective anti-HD therapeutic leads.

Quercetin's Restorative Properties in Male Mice with 3-Nitropropionic Acid-induced Huntington-like Symptoms: Molecular Docking, Behavioral, and Biochemical Assessment

The neurotoxicity of 3-Nitropropionic acid (3-NP) is well known. Herein, the prophylactic versus therapeutic effects of quercetin (QCT) were investigated against 3-NP-induced behavioral anomalies and oxidative neural damage. Thirty male mice were assigned into five groups; the negative control group, the QCT group (25 mg/kg/day, p.o. for 21 days), the 3-NP group (17 days), the prophylactic group (QCT administration for 14 consecutive days, and then 3-NP was administrated), the therapeutic group (3-NP was administrated and then QCT for 21 days). At the end of the animal treatment, behavioral studies were assessed. Subsequently, the brain sample tissues were assessed for oxidative stress-related parameters and histological evaluation. Moreover, the potential interaction between 3-NP and tumor necrosis factor-alpha (TNF-α) was evaluated by using a molecular docking study. 3-NP markedly led to neurotoxicity which was indicated by behavioral deficits (motor behavior, depression-like behavior, memory dysfunction, and passive avoidance) and oxidative damage. Blind and targeted molecular docking results showed good interaction between 3-NP and TNF-α. However, the prophylactic effects of QCT were superior to the therapeutic effects for attenuating 3-NP-induced neurobehavioral and oxidative neural changes in experimental mice, which histological changes of the brain's striatum region approved our findings. Taken together, the antioxidant activity of QCT remarkably could attenuate 3-NP-induced neurobehavioral deficits and mitochondrial dysfunctions in mice.

Azilsartan Attenuates 3-Nitropropinoic Acid-Induced Neurotoxicity in Rats: The Role of IĸB/NF-ĸB and KEAP1/Nrf2 Signaling Pathways

Huntington's disease (HD) is an autosomal-dominant neurodegenerative disorder characterized by motor, psychiatric and cognitive symptoms. Injection of 3-nitropropionic acid (3-NP) is a widely used experimental model for induction of HD. The current study aimed to inspect the potential neuroprotective properties of azilsartan (Azil), an angiotensin II type 1 receptor blocker (ATR1), in 3-NP-induced striatal neurotoxicity in rats. Rats were randomly allocated into five groups and treated for 14 days as follows: group I received normal saline; group II received Azil (10 mg/kg, p.o.); group III received 3-NP (10 mg/kg, i.p); group IV and V received Azil (5 or 10 mg/kg, p.o, respectively) 1 h prior to 3-NP injection. Both doses of Azil markedly attenuated motor and behavioural dysfunction as well as striatal histopathological alterations caused by 3-NP. In addition, Azil balanced striatal neurotransmitters levels as evidenced by the increase of striatal gamma-aminobutyric acid content and the decrease of glutamate content. Azil also amended neuroinflammation and oxidative stress via modulating IĸB/NF-ĸB and KEAP1/Nrf2 downstream signalling pathways, as well as reducing iNOS and COX2 levels. Moreover, Azil demonstrated an anti-apoptotic activity by reducing caspase-3 level and BAX/BCL2 ratio. In conclusion, the present study reveals the neuroprotective potential of Azil in 3-NP-induced behavioural, histopathological and biochemical changes in rats. These findings might be attributed to inhibition of ATR1/NF-κB signalling, modulation of Nrf2/KEAP1 signalling, anti-inflammatory, anti-oxidant and anti-apoptotic properties.

Neuroprotective effects of silymarin in 3-nitropropionic acid-induced neurotoxicity in male mice: improving behavioral deficits by attenuating oxidative stress and neuroinflammation

3-Nitropropionic acid (3-NP) is strongly believed to be an irreversible inhibitor of mitochondrial complex II, leading to neural damage. This study aimed to investigate the neuroprotective effects of silymarin against 3-NP-induced neurotoxicity in male mice. Six-week-old mice received subacute doses of 3-NP intraperitoneally for 17 days. Mice were given silymarin (70 mg/kg/day, P.O.) for 2 weeks before 3-NP administration or for 4 weeks after 3-NP administration. At the end of the treatment schedule, animals were evaluated for behavioral alterations. Subsequently, neuronal damage in the hippocampus region of the brain tissues, oxidative stress-related parameters (lipid peroxidation, nitric oxide, superoxide dismutase, glutathione, and total antioxidant capacity), and pro-inflammatory cytokine (TNF-α, IL-17, and IL-1β) levels were evaluated. Our results indicated that 3-NP treatment significantly (p < 0.05) tended to reduce motor coordination, memory, and neuronal antioxidant status while increasing pro-inflammatory cytokine levels. However, silymarin in both treatment and pretreatment protocols markedly (p < 0.05) attenuated the behavioral deficits, oxidative stress status, and neuroinflammation. The results of the current study suggest that the neuroprotective effect of silymarin against 3-NP-induced neurotoxicity might be due to the mitigation of oxidative stress status and provide insight into the therapeutic potential of silymarin.

A neoteric annotation on the advances in combination therapy for Parkinson's disease: nanocarrier-based combination approach and future anticipation. Part I: exploring theoretical insights and pharmacological advances

INTRODUCTION

Parkinson's disease (PD) is a neurological condition defined by a substantial reduction in dopamine-containing cells in the substantia nigra. Levodopa (L-Dopa) is considered the gold standard in treatment. Recent research has clearly shown that resistance to existing therapies can develop. Moreover, the involvement of multiple pathways in the nigrostriatal dopaminergic neuronal loss suggests that modifying the treatment strategy could effectively reduce this degeneration.

AREAS COVERED

This review summarizes the key concerns with treating PD patients and the combinations, aimed at effectively managing PD. Part I focuses on the clinical diagnosis at every stage of the disease as well as the pharmacological treatment strategies that are applied throughout its course. It methodically elucidates the potency of multifactorial interventions in attenuating the disease trajectory, substantiating the rationale for co-administration of dual or multiple therapeutic agents. Significant emphasis is laid on evidence-based pharmacological combinations for PD management.

EXPERT OPINION

By utilizing multiple drugs in a combination fashion, this approach can leverage the additive or synergistic effects of these agents, amplify the spectrum of treatment, and curtail the risk of side effects by reducing the dose of each drug, demonstrating significantly greater efficacy.

D-ribose-L-cysteine exhibits restorative neurobehavioral functions through modulation of neurochemical activities and inhibition oxido-inflammatory perturbations in rats exposed to polychlorinated biphenyl

Polychlorinated biphenyl (PCB) is potentially harmful environmental toxicant causing cognitive decline with depressive features. PCB-induced behavioral deficits are associated with neurochemical dysfunctions, immune changes, and oxidative stress. This study investigated the neuroprotective effects of D-ribose-L-cysteine (DRLC), a neuroprotective precursor element of glutathione on PCB-induced neurobehavioral impairments. Following the initial 15 days of PCB (2 mg/kg) exposure to rats, DRLC (50 mg/kg) was given orally for an additional 15 days, from days 16 to 30. Animals were assessed for behavioral effect such as changes in locomotion, cognition, and depression. Oxidative/nitrergic stress markers; antioxidant regulatory proteins paraoxonase-1 (PON-1), heme oxygenase-1 (HO-1), nuclear factor erythroid 2-related factor 2 (Nfr2), NADPH oxidase-1 (NOX-1), NAD(P)H quinone oxidoreductase 1 (NQO1), and neuroinflammation (NF-kβ, and TNF-α); and neurochemical metabolizing enzymes (acetylcholinesterase (AChE), monoamine oxidase-A and -B (MAO-A, MAO-B)) were carried out. The PCB-induced decline in locomotion, cognitive performance, and depressive-like features were reversed by DRLC. More specifically, PCB-induced oxidative and nitrergic stress, typified by reduced levels GSH, CAT, and SOD, accompanied by elevated MDA and nitrite were attenuated by DRLC. Additionally, DRLC restored the neuroinflammatory milieu indicated by decreased NF-kβ and TNF-α levels toward normal. Hyperactivities of AChE, MAO-A, MAO-B, PON-1, and NOX-1 levels as well as Nfr2, NQO1, and PON-1 due to PCB exposure were mitigated by DLRC. Our results suggest DRLC as a prospective neurotherapeutic agent against PCB-induced neurobehavioral impairments such as cognitive deficit and depressive-like feature through antioxidative and anti-nitrergic stress, anti-neuroinflammation, inhibition of brain metabolizing enzymes, and normalization of neurochemical homeostasis.

Mechanistic Study on the Possible Role of Embelin in Treating Neurodegenerative Disorders

Embelin (EMB) (2,5-Dihydroxy-3-undecyl-1,4-benzoquinone) is a natural benzoquinone extracted mainly from Embelia ribes (ER) and appear as vivid orange dots beneath the fruit's pericarp. It is being used to treat various diseases since ancient times in India. It has been ascribed as one of the 32 ayurvedic drugs of national importance in the National Medicinal Plant Board set up by the Government of India under the Ministry of Indian System of Medicine and Homeopathy. Embelin prevents neuronal oxidative damage by decreasing the peroxidation of lipids. Along with having antioxidant properties, it also prevents the production of amyloid-protein-related fibrils and blocks the progression of inflammatory cascades. Due to embelin's ability to cross the blood-brain barrier, its neuroprotective effects have been studied in the past using in vitro models of neuronal disorders such as convulsion and epilepsy, Alzheimer's disease, anxiety and depression, traumatic brain injury, cerebral ischemia, Huntington's disease, and multiple sclerosis. In addition to its neuroprotective effects, its role as an antitubercular, anti-cancer, antioxidant, astringent, anti-inflammatory, anti-bacterial, contraceptive, carminative, diuretic, and anthelmintic agent has also been studied. With docking studies and recent advancements in formulations of embelin including polyethylene and embelin micelles and embelin noisome preparations, embelin can prove to be a promising compound for its therapeutic actions in a wide range of diseases and disorders. The findings of docking studies suggest the binding ability of embelin to be similar to the standard drug in their respective disorders. In this review and docking analysis, we bring an outline of scientific evidence concerning the neuroprotective actions of embelin, still, further research is required for its prospective as a chief compound in clinical approaches.

Synthesis of chromium-D-phenylalanine complex and exploring its effects on reproduction and development in Drosophila melanogaster

The present study was undertaken to explore the effect of Chromium-D-phenylalanine (Cr (D-phe)3) on the reproduction and development of Drosophila melanogaster. Cr (D-phe)3 was synthesized and characterized by infrared spectral analysis, melting point (DSC), and UV spectral analysis. D. melanogaster was raised in corn flour agar medium containing 0, 5, 10, 15, and 20 μg/mL of Cr (D-phe)3. The effect of Cr (D-phe)3 was evaluated by observing the larval period, pupal period, percentage of egg hatching, morphometric analysis of eggs, larvae, pupae and adults, fertility, fecundity, lifespan of the emerged flies, and levels of antioxidant enzymes such as catalase, glutathione-S-transferase (GST), and superoxide dismutase (SOD) in the supernatant of flies homogenate suspension. The study results indicate that Cr (D-phe)3 showed beneficial effects on reproduction and development in D. melanogaster. Cr (D-phe)3 significantly improved the larval period, pupal period, percentage of egg hatching, morphometric characters of the larva, pupa, and adult, fertility, fecundity, and lifespan of D. melanogaster. Moreover, Cr (D-phe)3 also significantly elevated the levels of catalase (p < 0.01), GST (p < 0.05), and SOD (p < 0.01) in D. melanogaster, and results were statistically significant at the dose of 15 μg/mL. The study results indicate that Cr (D-phe)3 has a positive effect on the reproduction and development of D. melanogaster. The literature review revealed that there is a strong relationship between the physiology of metabolism, oxidative stress and reproduction and development. Several studies propose that Cr(III) influences insulin sensitivity and thereby the metabolism of carbohydrates, proteins, and fats. Cr (D-phe)3 also has antioxidant and anti-inflammatory properties. Hence, the observed beneficial effects of Cr (D-phe)3 on reproduction and development of D. melanogaster may be attributed to its physiological effect on carbohydrate, protein, and lipid metabolism and its antioxidant and anti-inflammatory properties.

Effect of embelin on inhibition of cell growth and induction of apoptosis in Acanthamoeba castellanii

Acanthamoeba castellanii is the causative agent of fatal encephalitis and blinding keratitis. Current therapies remain a challenge, hence there is a need to search for new therapeutics. Here, we tested embelin (EMB) and silver nanoparticles doped with embelin (EMB-AgNPs) against A. castellanii. Using amoebicidal assays, the results revealed that both compounds inhibited the viability of Acanthamoeba, having an IC50 of 27.16 ± 0.63 and 13.63 ± 1.08 μM, respectively, while causing minimal cytotoxicity against HaCaT cells in vitro. The findings suggest that both samples induced apoptosis through the mitochondria-mediated pathway. Differentially expressed genes analysis showed that 652 genes were uniquely expressed in treated versus untreated cells, out of which 191 were significantly regulated in the negative control vs. conjugate. Combining the analysis, seven genes (ARIH1, RAP1, H3, SDR16C5, GST, SRX1, and PFN) were highlighted as the most significant (Log2 (FC) value ± 4) for the molecular mode of action in vitro. The KEGG analysis linked most of the genes to apoptosis, the oxidative stress signaling pathway, cytochrome P450, Rap1, and the oxytocin signaling pathways. In summary, this study provides a thorough framework for developing therapeutic agents against microbial infections using EMB and EMB-AgNPs.

Neuroprotective potency of mangiferin against 3-nitropropionic acid induced Huntington's disease-like symptoms in rats: possible antioxidant and anti-inflammatory mechanisms

Huntington's disease (HD), a neurodegenerative disease, normally starts in the prime of adult life, followed by a gradual occurrence of psychiatric disturbances, cognitive and motor dysfunction. The daily performances and life quality of HD patients have been severely interfered by these clinical signs and symptoms until the last stage of neuronal cell death. To the best of our knowledge, no treatment is available to completely mitigate the progression of HD. Mangiferin, a naturally occurring potent glucoxilxanthone, is mainly isolated from the Mangifera indica plant. Considerable studies have confirmed the medicinal benefits of mangiferin against memory and cognitive impairment in neurodegenerative experimental models such as Alzheimer's and Parkinson's diseases. Therefore, this study aims to evaluate the neuroprotective effect of mangiferin against 3-nitropropionic acid (3-NP) induced HD in rat models. Adult Wistar rats (n = 32) were randomly allocated equally into four groups of eight rats each: normal control (Group I), disease control (Group II) and two treatment groups (Group III and Group IV). Treatment with mangiferin (10 and 20 mg/kg, p. o.) was given for 14 days, whereas 3-NP (15 mg/kg, i. p.) was given for 7 days to induce HD-like symptoms in rats. Rats were assessed for cognitive functions and motor coordination using open field test (OFT), novel object recognition (NOR) test, neurological assessment, rotarod and grip strength tests. Biochemical parameters such as oxidative stress markers and pro-inflammatory markers in brain hippocampus, striatum and cortex regions were evaluated. Histopathological study on brain tissue was also conducted using hematoxylin and eosin (H&E) staining. 3-NP triggered anxiety, decreased recognition memory, reduced locomotor activity, lower neurological scoring, declined rotarod performance and grip strength were alleviated by mangiferin treatment. Further, a significant depletion in brain malondialdehyde (MDA) level, an increase in reduced glutathione (GSH) level, succinate dehydrogenase (SDH), superoxide dismutase (SOD) and catalase (CAT) activities, and a decrease in tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) levels were observed in mangiferin treated groups. Mangiferin also mitigated 3-NP induced histopathological alteration in the brain hippocampus, striatum and cortex sections. It could be inferred that mangiferin protects the brain against oxidative damage and neuroinflammation, notably via antioxidant and anti-inflammatory activities. Mangiferin, which has a good safety profile, may be an alternate treatment option for treating HD and other neurodegenerative disorders. The results of the current research of mangiferin will open up new avenues for the development of safe and effective therapeutic agents in diminishing HD.

Pathways to healing: Plants with therapeutic potential for neurodegenerative diseases

Some of the greatest challenges in medicine are the neurodegenerative diseases (NDs), which remain without a cure and mostly progress to death. A companion study employed a toolkit methodology to document 2001 plant species with ethnomedicinal uses for alleviating pathologies relevant to NDs, focusing on its relevance to Alzheimer's disease (AD). This study aimed to find plants with therapeutic bioactivities for a range of NDs. 1339 of the 2001 plant species were found to have a bioactivity from the literature of therapeutic relevance to NDs such as Parkinson's disease, Huntington's disease, AD, motor neurone diseases, multiple sclerosis, prion diseases, Neimann-Pick disease, glaucoma, Friedreich's ataxia and Batten disease. 43 types of bioactivities were found, such as reducing protein misfolding, neuroinflammation, oxidative stress and cell death, and promoting neurogenesis, mitochondrial biogenesis, autophagy, longevity, and anti-microbial activity. Ethno-led plant selection was more effective than random selection of plant species. Our findings indicate that ethnomedicinal plants provide a large resource of ND therapeutic potential. The extensive range of bioactivities validate the usefulness of the toolkit methodology in the mining of this data. We found that a number of the documented plants are able to modulate molecular mechanisms underlying various key ND pathologies, revealing a promising and even profound capacity to halt and reverse the processes of neurodegeneration.

Barbigerone prevents scopolamine-induced memory impairment in rats by inhibiting oxidative stress and acetylcholinesterase levels

The current study was designed for the evaluation of barbigerone on memory loss. In this experimental study, 24 Wistar rats (n = 6) were used. Control rats and scopolamine (SCOP)-treated control group rats were orally administered with 3 ml of 0.5% sodium carboxymethyl cellulose (vehicle), whereas barbigerone was (10 and 20 mg kg-1) administered orally to the rats from the test group. During the 14-day treatment, control group rats were given 3 ml kg-1 day-1 saline, and all other groups were administered SCOP (1 mg kg-1 day-1, i.p.) 1 h after barbigerone p.o. treatment. The spontaneous alternation activities, learning capacities of a rat's memory were tested with Morris water maze and Y-maze. Reduced glutathione, malondialdehyde, acetylcholine esterase (AChE) and catalase (CAT) levels were measured in rat brain tissue as oxidative stress/antioxidant markers. Moreover, the levels of tumour necrosis factor, interleukin-6 (IL-6) and IL-1β were also estimated. Treatment with barbigerone in SCOP-administered rats dramatically reduced SCOP-induced neurobehavioural deficits, oxidative stress and neuroinflammatory markers, improved endogenous antioxidants, and restored AChE activity. By improving cholinergic function and reducing oxidative damage, barbigerone could mitigate the effects of SCOP-induced changes in the brain.

Glycyrrhizin prevents 3-nitropropionic acid-induced neurotoxicity by downregulating HMGB1/TLR4/NF-κB p65 signaling, and attenuating oxidative stress, inflammation, and apoptosis in rats

AIMS

Glycyrrhizin (Glyc) is a saponin triterpenoid that has signified its efficacy against Huntington's disease (HD). Nonetheless, its mechanism has not been fully clarified. Accordingly, this study was designed to evaluate the plausible mechanism of action of Glyc against 3-nitropropionic acid (3-NP)-induced HD.

MAIN METHODS

Rats were treated with Glyc (50 mg/kg, i.p.) for 3 weeks and 3-NP (10 mg/kg, i.p.) was administered at the latter 2 weeks alongside to induce HD.

KEY FINDINGS

Animals exposed to 3-NP revealed a reduction in body weight, neurobehavioral abnormalities, and various deleterious effects related to overexpression of HMGB1 such as oxidative stress, apoptosis, and inflammation. Promisingly, Glyc administration provided valuable effects by reversing the decline in body weight with improved neurobehavioral deficits. Ameliorating oxidative stress via restoring GSH, SOD, and Nrf2 alongside with MDA suppression was evident. Furthermore, Glyc switched the HMGB1/TLR4/NF-κB p65 signaling off, reduced IL-6, IL-β, TNF-α, caspase-3, and increased Bcl-2 as well as BDNF. All these beneficial effects were mirrored by a better histopathological picture upon using Glyc that suppressed gliosis by reducing GFAP expression as observed in the immunohistochemistry results.

SIGNIFICANCE

Accordingly, the current study demonstrated a promising neuroprotective effect of Glyc against experimentally induced HD through alleviating deleterious events by diverse mechanisms.

Neuroprotective Efficacy of Europinidin in Streptozotocin-Induced Memory Impairment by Modulation of Oxidative Stress, Inflammatory Mediators, and Cholinesterase Activity in Rats

Materials and Methods

Oral acute toxicity studies were performed to evaluate the toxicological effects of europinidin in animals. In this study, four different animal groups (n = 6) were used. Group I was the normal control, group II was the STZ-induced diabetes control, group III was STZ + europinidin-treated (10 mg/kg), and group IV was STZ + europinidin-treated (10 mg/kg). The efficacy of europinidin at a dose of 10 mg/kg and 20 mg/kg was studied with single-dose administration of streptozotocin, which experimentally induced memory impairments in Wistar male rats for 38 days. The mean body weight and blood glucose levels were recorded at the initial and end of the study. The two behavioural paradigms (Y-maze and Morris water maze) were performed to evaluate spatial and working memory in rats. The biochemical parameters such as acetylcholinesterase, choline acetyltransferase, superoxide dismutase, glutathione transferase, malonaldehyde, catalase, and nitric oxide level as hallmarks of oxidative stress were measured. Additionally, the proinflammatory parameters were also determined to evaluate the neuroinflammatory responses associated with streptozotocin such as tumor necrosis factor-alpha (TNF-α) interleukin-1β (IL-1β), interleukin (IL-6), nuclear factor-kappa B (NF-ƙB), interleukin (IL-10), and nuclear factor-erythroid factor 2-related factor 2 (Nrf2) in the perfused brain.

Results

The rats in the europinidin-treated group exhibited a significant restoration of body weight and blood glucose level as compared with the streptozotocin control group. Furthermore, europinidin significantly modulated the spatial and working memory in rats, when assessed through behavioural paradigms. Streptozotocin caused a significant alteration in biochemical, neuronal enzymatic, and neuroinflammatory parameters, which were significantly restored to normal levels by europinidin.

Conclusion

The present study attributed the neuroprotective efficacy of europinidin in experimental animal models by subsiding the several biomarkers of oxidative stress, neuroinflammation, and neuronal enzymatic activities.

The Emerging Landscape of Natural Small-molecule Therapeutics for Huntington's Disease

Huntington's disease (HD) is a rare and fatal neurodegenerative disorder with no diseasemodifying therapeutics. HD is characterized by extensive neuronal loss and is caused by the inherited expansion of the huntingtin (HTT) gene that encodes a toxic mutant HTT (mHTT) protein having expanded polyglutamine (polyQ) residues. Current HD therapeutics only offer symptomatic relief. In fact, Food and Drug Administration (FDA) approved two synthetic small-molecule VMAT2 inhibitors, tetrabenazine (1) and deutetrabenazine (2), for managing HD chorea and various other diseases in clinical trials. Therefore, the landscape of drug discovery programs for HD is evolving to discover disease- modifying HD therapeutics. Likewise, numerous natural products are being evaluated at different stages of clinical development and have shown the potential to ameliorate HD pathology. The inherent anti-inflammatory and antioxidant properties of natural products mitigate the mHTT-induced oxidative stress and neuroinflammation, improve mitochondrial functions, and augment the anti-apoptotic and pro-autophagic mechanisms for increased survival of neurons in HD. In this review, we have discussed HD pathogenesis and summarized the anti-HD clinical and pre-clinical natural products, focusing on their therapeutic effects and neuroprotective mechanism/s.

The Emerging Landscape of Small-Molecule Therapeutics for the Treatment of Huntington's Disease

Huntington's disease (HD) is a progressive neurodegenerative disorder caused by a CAG repeat expansion in the huntingtin gene (HTT). The new insights into HD's cellular and molecular pathways have led to the identification of numerous potent small-molecule therapeutics for HD therapy. The field of HD-targeting small-molecule therapeutics is accelerating, and the approval of these therapeutics to combat HD may be expected in the near future. For instance, preclinical candidates such as naphthyridine-azaquinolone, AN1, AN2, CHDI-00484077, PRE084, EVP4593, and LOC14 have shown promise for further optimization to enter into HD clinical trials. This perspective aims to summarize the advent of small-molecule therapeutics at various stages of clinical development for HD therapy, emphasizing their structure and design, therapeutic effects, and specific mechanisms of action. Further, we have highlighted the key drivers involved in HD pathogenesis to provide insights into the basic principle for designing promising anti-HD therapeutic leads.

Phytochemistry, Pharmacology and Molecular Mechanisms of Herbal Bioactive Compounds for Sickness Behaviour

The host's response to acute infections or tissue injury is a sophisticated and coordinated adaptive modification called sickness behaviour. Many herbs have been studied for their ability to protect animals against experimentally induced sickness behaviour. However, there is a lack of knowledge and experimental evidence on the use of herbal bioactive compounds (HBACs) in the management of sick behaviour. The goal of this review is to provide a concise summary of the protective benefits and putative mechanisms of action of phytochemicals on the reduction of lipopolysaccharide (LPS)-induced sickness behaviour. Relevant studies were gathered from the search engines Scopus, ScienceDirect, PubMed, Google Scholar, and other scientific databases (between 2000 and to date). The keywords used for the search included "Lipopolysaccharide" OR "LPS" OR "Sickness behaviour" OR "Sickness" AND "Bioactive compounds" OR "Herbal medicine" OR "Herbal drug" OR "Natural products" OR "Isolated compounds". A total of 41 published articles that represented data on the effect of HBACs in LPS-induced sickness behaviour were reviewed and summarised systemically. There were 33 studies that were conducted in mice and 8 studies in rats. A total of 34 HBACs have had their effects against LPS-induced changes in behaviour and biochemistry investigated. In this review, we examined 34 herbal bioactive components that have been tested in animal models to see if they can fight LPS-induced sickness behaviour. Future research should concentrate on the efficacy, safety, and dosage needed to protect against illness behaviour in humans, because there is a critical shortage of data in this area.

Effects of the Anthocyanin Hirsutidin on Gastric Ulcers: Improved Healing through Antioxidant Mechanisms

The goal of this study was to determine the effect of hirsutidin on ethanol-induced stomach ulcers in rats. Rats (n = 24 rats/group) were separated at random into the following groups: normal saline-treated (normal control), ethanol-treated (ethanol control), 10 mg/kg hirsutidin + ethanol-treated (hirsutidin 10), and 20 mg/kg hirsutidin + ethanol-treated (hirsutidin 20). All the groups received the respective treatment orally for 7 days. On day 7, i.e., after 24 h of fasting, except for the normal control group, all the groups orally received 5 mL/kg of ethanol. Four hours later, rats were anaesthetized, serum was isolated from the blood, and biochemical tests were performed. The stomach tissue was utilized for ulcer grading, histology, and biochemical analysis. The rats developed stomach acidity and ulcers after being given ethanol based on increased ulcer score, disturbed cellular architecture, increased oxidative stress, myeloperoxidase and decreased endogenous antioxidants, and nitric oxide and prostaglandin E2 concentration. Ethanol-treated rats also displayed increased tumor necrosis factor-α, aspartate aminotransferase, alanine transaminase, alkaline phosphatase, and inflammatory cytokines. The treatment with hirsutidin protected and significantly restored all serum parameters in ethanol-induced stomach ulcers and may have antiulcer activity.

Anti-Huntington's Effect of Rosiridin via Oxidative Stress/AchE Inhibition and Modulation of Succinate Dehydrogenase, Nitrite, and BDNF Levels against 3-Nitropropionic Acid in Rodents

Background: Rosiridin is a compound extracted from Rhodiola sachalinensis; water extracts of Rhodiola root elicit positive effects on the human central nervous system and improve brain function. They are also thought to be beneficial to one's health, in addition to being antioxidants. The present study aims to evaluate the anti-Huntington's effect of rosiridin against 3-nitropropionic acid (3-NPA)-induced Huntington's disease (HD)-like effects in rats. Materials and Methods: The acute toxicity in rats was elucidated to track the conceivable toxicities in the rats. The effectiveness of rosiridin at a dosage of 10 mg/kg was evaluated against several dose administrations of 3-NPA-induced HD-like symptoms in the rats for 22 days. At the end of the study, behavioral parameters were assessed as a hallmark for the cognitive and motor functions in the rats. Similarly, after the behavioral assessment, the animals were sacrificed to obtain a brain tissue homogenate. The prepared homogenate was utilized for the estimation of several biochemical parameters, including oxidative stress (glutathione, catalase, and malondialdehyde), brain-derived neurotrophic factor and succinate dehydrogenase activity, and the glutamate and acetylcholinesterase levels in the brain. Furthermore, inflammatory mediators linked to the occurrence of neuroinflammation in rats were evaluated in the perfused brain tissues. Results: The rosiridin-treated group exhibited a significant restoration of behavioral parameters, including in the beam-walk test, latency in falling during the hanging wire test, and percentage of memory retention during the elevated plus-maze test. Further, rosiridin modulated several biochemical parameters, including oxidative stress, pro-inflammatory activity, brain-derived neurotrophic factor, nitrite, and acetylcholinesterase as compared to disease control group that was treated with 3-NPA. Conclusions: The current study exhibits the anti-Huntington's effects of rosiridin in experimental animal models.

Reviewing the Traditional/Modern Uses, Phytochemistry, Essential Oils/Extracts and Pharmacology of Embelia ribes Burm

OBJECTIVES

Embelia ribes Burm. (E. ribes, Myrsinaceae), also known as Vidanga in Ayurveda, has been shown to have significant therapeutic benefits on several disorders, and its main chemical bioactive constituent, embelin, has the therapeutic potential to be converted into innovative drugs, which is why it has recently received considerable interest. In the present work, we provide a higher level of comprehension, awareness, and extensive knowledge of the traditional uses, phytochemistry, and pharmacological characteristics of E. ribes throughout the last several decades (February 1965 to June 2021), emphasizing the importance of the study of essential oils extracted from E. ribes, which show a major potential for exerting antioxidant and anti-inflammatory activity.

MATERIALS AND METHODS

Google Scholar, MEDLINE, EMBASE, Scifinder, Scopus, and ScienceDirect were used to conduct a thorough literature search.

RESULTS

E. ribes is high in essential oils, alkaloids, flavonoids, steroids, and phenolics, all of which have medicinal benefits. The essential oils/extracts and isolated chemical constituents exhibited antioxidant activity, wound healing, antidiabetic, central nervous system (CNS)-related disease, antiviral, antiobesity, cardioprotective, antifungal, antibacterial, and antifertility activity, among other promising pharmacological effects.

CONCLUSION

The translation between traditional applications and modern medicine may make E. ribes a promising target for the implementation of innovative medication. To investigate the efficacy and safety profile of E. ribes, further high-quality preclinical studies using advanced methodologies are required.

Neuroprotective effect of standardized extracts of three Lactuca sativa Linn. varieties against 3-NP induced Huntington's disease like symptoms in rats

OBJECTIVES

The study was aimed to evaluate the efficacy of three commonly consumed Lactuca sativa (LS) Linn. varieties viz., Grand rapid, Lollo rosso and Iceberg (Asteraceae) against 3-NP induced HD like symptoms in rats.

METHODS

Ethanol extracts of leaves of three LS varieties were prepared, and standardized on the basis of quercetin content using HPLC. These extracts (100 and 200 mg kg, p.o. for 20 days) were evaluated for their neuroprotective effect against 3-NP (10 mg/kg, i.p. for 14 days) induced neurotoxicity in male Wistar rats. The extract that exhibited maximum activity was successively fractionated using hexane, ethyl acetate, n-butanol and aqueous in increasing order of polarity. These fractions were also evaluated (dose equivalent to the dose of the extract of LS variety exhibiting maximum activity) for their neuroprotective effect. The protective effect of extracts and fractions was evaluated using different behavioral (rota rod, actophotometer, beam walk and Morris water maze) and biochemical (malondialdehyde, nitrite, superoxide dismutase, catalase and reduced glutathione) parameters.

RESULTS

3-NP elicit marked deterioration in motor coordination, locomotor activity and memory in comparison to control group. Standardized ethanol extract of grand rapid (200 mg/kg) exhibited maximum activity amongst the three tested varieties. Therefore, its fractions were also evaluated, and n-butanol fraction (40 mg/kg) exhibited maximum attenuation of 3-NP induced HD like symptoms which was evident from improved behavioral and biochemical parameters.

DISCUSSION

The results exhibit that LS (Grand rapid variety) prophylaxis mitigated 3-NP induced neurotoxicity and HD like symptoms in rats due to its potent antioxidant potential.

Addressing Peroxisome Proliferator-Activated Receptor-gamma in 3-Nitropropionic Acid-Induced Striatal Neurotoxicity in Rats

Telmisartan (TEL) is an angiotensin II type 1 receptor blocker and a partial activator of peroxisome proliferator-activated receptor-gamma (PPARγ), which regulates inflammatory and apoptotic pathways. Increasing evidence has demonstrated the PPARγ agonistic property of TEL in several brain disorders. This study aims to explore the neuroprotective impact of TEL in 3-nitropropionic acid (3-NP)-induced neurotoxicity in rats. The PPARγ effect of TEL was affirmed by using the PPARγ agonist pioglitazone (PIO), and the antagonist GW9662. 3-NP led to a significant reduction in body weight alongside motor and cognitive functioning. The striata of the 3-NP-treated rats showed energy-deficit, microglia-mediated inflammatory reactions, apoptotic damage as well as histopathological lesions. PIO and TEL improved motor and cognitive perturbations induced by 3-NP, as confirmed by striatal histopathological examination, energy restoration, and neuronal preservation. Both drugs improved mitochondrial biogenesis evidenced by elevated mRNA expression of PPARγ, PGC-1α, and TFAM, alongside increased striatal ATP and SDH. The mitochondrial effect of TEL was beyond PPARγ activation. As well, their anti-inflammatory effect was attributed to suppression of microglial activation, and protein expression of pS536 p65 NF-κB with marked attenuation of striatal inflammatory mediator's release. Anti-inflammatory cytokine IL-10 expression was concurrently increased. TEL effectively participated in neuronal survival as it promoted phosphorylation of Akt/GSK-3β, further increased Bcl-2 expression, and inhibited cleavage of caspase-3. Interestingly, co-treatment with GW9662 partially revoked the beneficial effects of TEL. These findings recommend that TEL improves motor and cognitive performance, while reducing neuronal inflammation and apoptosis in 3-NP-induced neurotoxicity via a PPARγ-dependent mechanism.

Inosine attenuates 3-nitropropionic acid-induced Huntington's disease-like symptoms in rats via the activation of the A2AR/BDNF/TrKB/ERK/CREB signaling pathway

Huntington's disease (HD) is an autosomal dominant inherited neurodegenerative disease characterized by involuntary bizarre movements, psychiatric symptoms, dementia, and early death. Several studies suggested neuroprotective activities of inosine; however its role in HD is yet to be elucidated. The current study aimed to demonstrate the neuroprotective effect of inosine in 3-nitropropionic acid (3-NP)-induced neurotoxicity in rats while investigating possible underlying mechanisms. Rats were randomly divided into five groups; group 1 received i.p. injections of 1% DMSO, whereas groups 2, 3, 4, and 5 received 3-NP (10 mg/kg, i.p.) for 14 days, concomitantly with inosine (200 mg/kg., i.p.) in groups 3, 4, and 5, SCH58261, a selective adenosine 2A receptor (A2AR) antagonist, (0.05 mg/kg, i.p.) in group 4, and PD98059, an extracellular signal-regulated kinase (ERK) inhibitor, (0.3 mg/kg, i.p.) in group 5. Treatment with inosine mitigated 3-NP-induced motor abnormalities and body weight loss. Moreover, inosine boosted the striatal brain-derived neurotrophic factor (BDNF) level, p-tropomyosin receptor kinase B (TrKB), p-ERK, and p-cAMP response element-binding protein (CREB) expression, which subsequently suppressed oxidative stress biomarkers (malondialdehyde and nitric oxide) and pro-inflammatory cytokines (tumor necrosis factor alpha and interleukin-1β) and replenished the glutathione content. Similarly, histopathological analyses revealed decreased striatal injury score, the expression of the glial fibrillary acidic protein, and neuronal loss after inosine treatment. These effects were attenuated by the pre-administration of SCH58261 or PD98059. In conclusion, inosine attenuated 3-NP-induced HD-like symptoms in rats, at least in part, via the activation of the A2AR/BDNF/TrKB/ERK/CREB signaling pathway.

Butin Attenuates Arthritis in Complete Freund's Adjuvant-Treated Arthritic Rats: Possibly Mediated by Its Antioxidant and Anti-Inflammatory Actions

The present research work was planned to evaluate the antioxidant and anti-inflammatory actions of butin in preventing complete Freund’s adjuvant-induced arthritis in rats. Adult Wistar rats (200–240 g) were segregated equally into four groups: Group I (normal) and Group II complete Freund’s adjuvant (CFA control) were administered orally with 3 ml/kg of 0.5% SCMC (vehicle); Group III and Group IV were test groups and orally administered 25 and 50 mg/kg of butin. These oral treatments were administered for a total of 21 days. In the 21-day treatment schedule, on the first day, animals from group I (normal control) were injected a single dose of normal saline (0.1 ml) intradermally into one of the hind paws, and animals from Group II to IV were injected CFA (0.1 ml) intradermally into one of the hind paws. During the treatment schedule, the volume of the hind paw and body weight were recorded at every 7 days intervals, and animals were scored for severe arthritis on days 17, 19, and 21. On the 22nd day, samples of blood were withdrawn by puncturing the retro-orbital sinus for analysis of RBC, WBC, hemoglobin, ALT, AST, ALP, PGE2, and cytokines. After blood withdrawal, animals were euthanized; the paw was separated by cutting at the ankle joint and used for analysis of oxidative stress and antioxidant parameters, as well as for the histopathological study. Administration of butin to CFA-treated animals significantly attenuated the CFA-induced inflammatory response, oxidative stress, and reversed the histopathological alteration towards normal. According to the findings, butin has anti-inflammatory and anti-arthritic properties in rats with CFA-induced arthritis.

A prognostic study on the effect of post-traumatic stress disorder on cerebral ischaemia reperfusion-induced stroke

OBJECTIVES

Previous studies have been established that persons who experienced a stroke are soon likely to develop several anxiety disorders. In which one of the major anxiety disorders is Post-traumatic Stress Disorder (PTSD). Yet, the likelihood of PTSD in conjunction with cerebral stroke has not been well described. Hence, we evaluated the impact of PTSD on cerebral stroke in rodents subjected to single prolonged stress (SPS) and bilateral common carotid artery occlusion (BCCAo), respectively.

METHODS

The relation between PTSD and cerebral stroke is evaluated by performing behavioural, biochemical, histopathological, and brain lesion area measurement studies.

RESULTS

Interestingly, SPS + BCCAo induction increased behavioural abnormalities like cognitive impairment and anxiety-like behaviour compared to SPS and BCCAo groups alone. Motor impairment was also observed in SPS + BCCAo rats compared to SPS rats, whereas no change with BCCAo rats. Furthermore, increased brain tissue MDA, acetylcholinesterase, and decreased SOD, catalase, and GSH were observed in SPS + BCCAo subjected rats compared to SPS and BCCAo rats alone. Additionally, SPS + BCCAo induction considerably increased the plasma corticosterone levels and caused severe neurotransmitter alterations. The SPS + BCCAo exposure significantly increased the brain lesion area in comparison with BCCAo rats. Moreover, severe histopathological alterations were observed in the hippocampus (CA1) of SPS + BCCAo rats compared to SPS and BCCAo rats alone.

CONCLUSIONS

In conclusion, our study results suggested that SPS-induced PTSD may aggravate the BCCAo induced cerebral ischaemia-reperfusion injury.

Anti-Huntington's Effect of Butin in 3-Nitropropionic Acid-Treated Rats: Possible Mechanism of Action

Butin has a strong antioxidant plus anti-inflammatory action and it is reported to be protective in oxidative stress-induced mitochondrial dysfunction. Butin has been shown to protect the mouse hippocampus HT22 cells from glutamate-induced neurotoxicity. The current investigation was planned to assess anti-Huntington's effect of butin in 3-nitropropionic acid-treated rats. A total of 32 Wistar rats (200-240 g) were equally segregated into four groups. Groups I and II were treated with vehicle (0.3 ml/100 g) and groups III and IV received butin 25 and 50 mg/kg for 15 days. Daily 1 h post above oral treatments, 3 ml/kg of normal saline was injected (i.p.) to group I animals and 10 mg/kg of 3-NP was injected (i.p.) to II and IV groups for 15 days. During the experimental schedule, behavioral tests were conducted for animals. On day 15, after behavioral parameters, animals were sacrificed and brains were removed for biochemical tests. Systemic administration of 3-NP induced neurobehavioral deficits which resulted in reduced spontaneous locomotor activity, motor incoordination, learning ability, and memory in the animals. Moreover, 3-NP depleted endogenous antioxidants (GSH, catalase, and SOD), mitochondrial complexes activities (I, II, IV, and MTT assay), elevated LDH, MDA, nitrite, and AchE. Administration of butin significantly improved neurobehavioral impairments, nitrative and oxidative stress, activities of mitochondrial enzyme complex, and reduced AchE levels in rat brain.

Embelin and levodopa combination therapy for improved Parkinson's disease treatment

Parkinson’s disease (PD), a progressive neurodegenerative disorder, affects dopaminergic neurons. Oxidative stress and gut damage play critical roles in PD pathogenesis. Inhibition of oxidative stress and gut damage can prevent neuronal death and delay PD progression. The objective of this study was to evaluate the therapeutic effect of embelin or the combination with levodopa (LD) in a rotenone-induced PD mouse model. At the end of experimentation, the mice were sacrificed and the midbrain was used to evaluate various biochemical parameters, such as nitric oxide, peroxynitrite, urea, and lipid peroxidation. In the substantia nigra (midbrain), tyrosine hydroxylase (TH) expression was examined by immunohistochemistry, and Nurr1 expression was evaluated by western blotting. Gut histopathology was evaluated on tissue sections stained with hematoxylin and eosin. In silico molecular docking studies of embelin and α-synuclein (α-syn) fibrils were also performed. Embelin alone or in combination with LD ameliorated oxidative stress and gut damage. TH and Nurr1 protein levels were also significantly restored. Docking studies confirmed the affinity of embelin toward α-syn. Taken together, embelin could be a promising drug for the treatment of PD, especially when combined with LD.

Nano-ivabradine averts behavioral anomalies in Huntington's disease rat model via modulating Rhes/m-tor pathway

Huntington's disease (HD) is characterized by abnormal involuntary movements together with cognitive impairment and disrupted mood changes. 3-nitropropionic acid (3-NP) is one of the chemo-toxic models used to address the striatal neurotoxicity pattern encountered in HD. This study aims to explain the neuroprotective effect of nano-formulated ivabradine (nano IVA) in enhancing behavioral changes related to 3-NP model and to identify the involvement of ras homolog enriched striatum (Rhes)/mammalian target of rapamycin (m-Tor) mediated autophagy pathway. Rats were divided into 6 groups, the first 3 groups received saline (control), ivabradine (IVA), nano IVA respectively, the fourth received a daily dose of 3-NP (20 mg/kg, s.c) for 2 weeks, the fifth received 3-NP + IVA (1 mg/kg, into the tail vein, every other day for 1 week) and the last group received 3-NP + nano IVA (1 mg/kg, i.v, every other day for 1 week). Interestingly, nano IVA reversed motor disabilities, improved memory function and overcame the psychiatric changes. It boosted expression of autophagy markers combined with down regulation of Rhes, m-Tor and b-cell lymphoma 2 protein levels. Also, it restored the normal level of neurotransmitters and myocardial function related-proteins. Histopathological examination revealed a preserved striatal structure with decreased number of darkly-degenerated neurons. In conclusion, the outcomes of this study provide a well-recognized clue for the promising neuroprotective effect of IVA and the implication of autophagy and Rhes/m-Tor pathways in the 3-NP induced HD and highlight the fact that nano formulations of IVA would be an auspicious approach in HD therapy.

Rosinidin Attenuates Lipopolysaccharide-Induced Memory Impairment in Rats: Possible Mechanisms of Action Include Antioxidant and Anti-Inflammatory Effects

The investigation aimed to evaluate the favourable effects of rosinidin in lipopolysaccharide (LPS)-induced learning and memory impairment in rats. Adult Wistar rats (150–200 g) were segregated equally into four different groups and treated as below: Group 1 (normal) and Group 2 (LPS control) were administered orally with 3 mL of 0.5% SCMC (vehicle); Group 3 and Group 4 were test groups and orally administered with rosinidin lower dose (10 mg/kg) and higher dose 20 mg/kg. Daily, 1 h post-offer mentioned treatments, Group 1 animals were injected with normal saline (i.p.) and groups 2–4 were treated with 1 mg/kg/day of LPS. This treatment schedule was followed daily for 7 days. During the treatment, schedule rats were evaluated for spontaneous locomotor activity, memory, and learning abilities. The biochemical assessment was carried out of acetylcholine esterase (AChE), endogenous antioxidants (GSH, SOD, GPx, and catalase), oxidative stress marker MDA, neuroinflammatory markers (IL-6, IL-1β, TNF-α, and NF-κB), and BDNF. LPS-induced reduced spontaneous locomotor activity and memory impairment in the animals. Moreover, LPS reduced GSH, SOD, GPx, and catalase levels; altered activities of AChE; elevated levels of MDA, IL-6, IL-1β, TNF-α, and NF-κB; and attenuated the levels of BDNF in brain tissue. Administration of rosinidin to LPS-treated animals significantly reduced LPS-induced neurobehavioral impairments, oxidative stress, neuroinflammatory markers, and reversed the Ach enzyme activities and BDNF levels towards normal. Results demonstrated that rosinidin attenuates the effects of LPS on learning memory in rats.

Ginsenoside Rg1 exerts neuroprotective effects in 3-nitropronpionic acid-induced mouse model of Huntington's disease via suppressing MAPKs and NF-κB pathways in the striatum

Huntington's disease (HD) is one of main neurodegenerative diseases, characterized by striatal atrophy, involuntary movements, and motor incoordination. Ginsenoside Rg1 (Rg1), an active ingredient in ginseng, possesses a variety of neuroprotective effects with low toxicity and side effects. In this study, we investigated the potential therapeutic effects of Rg1 in a mouse model of HD and explored the underlying mechanisms. HD was induced in mice by injection of 3-nitropropionic acid (3-NP, i.p.) for 4 days. From the first day of 3-NP injection, the mice were administered Rg1 (10, 20, 40 mg·kg^-1, p.o.) for 5 days. We showed that oral pretreatment with Rg1 alleviated 3-NP-induced body weight loss and behavioral defects. Furthermore, pretreatment with Rg1 ameliorated 3-NP-induced neuronal loss and ultrastructural morphological damage in the striatum. Moreover, pretreatment with Rg1 reduced 3-NP-induced apoptosis and inhibited the activation of microglia, inflammatory mediators in the striatum. We revealed that Rg1 exerted neuroprotective effects by suppressing 3-NP-induced activation of the MAPKs and NF-κΒ signaling pathways in the striatum. Thus, our results suggest that Rg1 exerts therapeutic effects on 3-NP-induced HD mouse model via suppressing MAPKs and NF-κΒ signaling pathways. Rg1 may be served as a novel therapeutic option for HD.

Ellagic acid prevents 3-nitropropionic acid induced symptoms of Huntington's disease

Mitochondrial abnormalities and redox imbalance are major pathogenic factors in progression of Huntington's disease (HD), manifested clinically by affective, motor, cognitive, and psychiatric incompetence. Antioxidants behold much promise in mitigation of several pathological facets in HD. Ellagic acid (EA) is a naturally derived polyphenol acknowledged for potent neuroprotective abilities that enabled its significance amongst popular brain tonics. The present study is aimed to examine the outcome of EA pre-treatment in 3-nitropropionic acid (3-NP) rat prototype of HD. Separate rat groups were pre-treated with EA (25, 50, and 100 mg/kg, p.o.) for 21 days and 3-NP (10 mg/kg, i.p.) was given for 14 days alongside to induce symptoms of HD. The physical/motor functions (narrow beam paradigm, footprint study, hanging-wire assessment) and cognitive abilities using elevated plus maze and novel object recognition task were evaluated. Entire brain was isolated and succinate dehydrogenase activity and parameters of oxido-nitrosative stress were assessed in mitochondrial fraction. 3-NP accrued oxido-nitrosative stress and significant decrease in succinate dehydrogenase activity caused motor and cognitive deficits in rats. EA pre-treatment resurrected succinate dehydrogenase activity in 3-NP treated rats that indicated preservation of mitochondrial function. A significant decrease in thiobarbituric acid reactive substances and nitrite levels and increase in glutathione and catalase activity by EA in 3-NP treated rats was noted. EA protected the rats against 3-NP triggered cognitive insufficiency and motor disturbances. It can be inferred that ellagic acid protects against 3-NP induced mitochondrial dysfunction and oxido-nitrosative stress in the brain. EA supplements or nutraceuticals might possess protective potential against symptoms of HD.

Naringenin mitigates behavioral alterations and provides neuroprotection against 3-nitropropinoic acid-induced Huntington's disease like symptoms in rats

BACKGROUND

Naringenin is a powerful antioxidant and anti-inflammatory flavonoid which has been widely used as a therapeutic agent in various toxic models. However, few studies have clearly discussed the neuromodulatory effects of naringenin against different neurodegenerative disorders.

AIM

We investigated the neuroprotective efficacy of naringenin against 3-nitropropionic acid (3-NP)-induced neurobehavioral, biochemical and histopathological alterations in rats.

METHODS

Albino Wistar rats were randomly divided into three experimental groups. Group 1, the vehicle administered group, received saline. Group 2 received 3-NP (20 mg/kg body weight, i.p.) for 4 consecutive days. Group 3 received naringenin (50 mg/kg body weight, p.o.) twice daily for a period of 4 days, 30 min before and 6 h after the 3-NP administration. On the 5th day, neurobehavioral experiments were performed to access the behavioral outcomes and the striatum tissue was used for analysis of the monoamine oxidase (MAO) activity and serotonin (5-HT) levels. In addition, astrocytes activation was observed by glial fibrillary acidic protein (GFAP) immunostaining.

RESULTS

Our results showed that naringenin co-treatment provides neuroprotection against 3-NP-induced neurological disorders. Naringenin also increased the MAO activity and 5-HT levels in the striatum. Moreover, co-treatment with naringenin reduced the expression of GFAP protein in the striatal part and significantly attenuated the neuronal cell death. The findings of the present study suggest that naringenin provides neuroprotection and mitigates neurobehavioral alterations in experimental rats.

CONCLUSION

The results show that co-treatment with naringenin ameliorates 3-NP-induced HD-like symptoms in rats.

Using mitochondrial respiration inhibitors to design a novel model of bipolar disorder-like phenotype with construct, face and predictive validity

We mimicked mild mitochondrial-distress robustly reported in bipolar-disorder (BD) by chronic exposure to uniquely low doses of inhibitors of mitochondrial-respiration complexes in vitro and in vivo. Exposure of the neuronal-originating SH-SY5Y cells to very low dose (10 pM) rotenone, a mitochondrial-respiration complex (Co)I inhibitor, for 72 or 96 h did not affect cell viability and reactive oxygen species (ROS) levels. Yet, it induced a dual effect on mitochondrial-respiration: overshooting statistically significant several-fold increase of most oxygen-consumption-rate (OCR) parameters vs. significantly decreased all OCR parameters, respectively. Chronic low doses of 3-nitropropionic acid (3-NP) (CoII inhibitor) did not induce long-lasting changes in the cells' mitochondria-related parameters. Intraperitoneal administration of 0.75 mg/kg/day rotenone to male mice for 4 or 8 weeks did not affect spontaneous and motor activity, caused behaviors associated with mania and depression following 4 and 8 weeks, respectively, accompanied by relevant changes in mitochondrial basal OCR and in levels of mitochondrial-respiration proteins. Our model is among the very few BD-like animal models exhibiting construct (mild mitochondrial dysfunction), face (decreased/increased immobility time in the forced-swim test, increased/decreased consumption of sweet solution, increased/decreased time spent in the open arms of the elevated plus maze) and predictive (reversal of rotenone-induced behavioral changes by lithium treatment) validity. Our rotenone regime, employing doses that, to the best of our knowledge, have never been used before, differs from those inducing Parkinson's-like models by not affecting ROS-levels and cell-viability in vitro nor motor activity in vivo.

Protective Effect of Natural Products against Huntington's Disease: An Overview of Scientific Evidence and Understanding Their Mechanism of Action

Huntington's disease (HD), a neurodegenerative disease, normally starts in the prime of adult life, followed by a gradual occurrence of characteristic psychiatric disturbances and cognitive and motor dysfunction. To the best of our knowledge, there is no treatment available to completely mitigate the progression of HD. Among various therapeutic approaches, exhaustive literature reports have confirmed the medicinal benefits of natural products in HD experimental models. Building on this information, this review presents a brief overview of the neuroprotective mechanism(s) of natural products against in vitro/in vivo models of HD. Relevant studies were identified from several scientific databases, including PubMed, ScienceDirect, Scopus, and Google Scholar. After screening through literature from 2005 to the present, a total of 14 medicinal plant species and 30 naturally isolated compounds investigated against HD based on either in vitro or in vivo models were included in the present review. Behavioral outcomes in the HD in vivo model showed that natural compounds significantly attenuated 3-nitropropionic acid (3-NP) induced memory loss and motor incoordination. The biochemical alteration has been markedly alleviated with reduced lipid peroxidation, increased endogenous enzymatic antioxidants, reduced acetylcholinesterase activity, and increased mitochondrial energy production. Interestingly, following treatment with certain natural products, 3-NP-induced damage in the striatum was ameliorated, as seen histologically. Overall, natural products afforded varying degrees of neuroprotection in preclinical studies of HD via antioxidant and anti-inflammatory properties, preservation of mitochondrial function, inhibition of apoptosis, and induction of autophagy.

Epigallocatechin-3-gallate PEGylated poly(lactic-co-glycolic) acid nanoparticles mitigate striatal pathology and motor deficits in 3-nitropropionic acid intoxicated mice

Aim: To compare free and nanoparticle (NP)-encapsulated epigallocatechin-3-gallate (EGCG) for the treatment of Huntington's disease (HD)-like symptoms in mice. Materials & methods: EGCG was incorporated into PEGylated poly(lactic-co-glycolic) acid NPs with ascorbic acid (AA). HD-like striatal lesions and motor deficit were induced in mice by 3-nitropropionic acid-intoxication. EGCG and EGCG/AA NPs were co-administered and behavioral motor assessments and striatal histology performed after 5 days. Results: EGCG/AA NPs were significantly more effective than free EGCG in reducing motor disturbances and depression-like behavior associated with 3-nitropropionic acid toxicity. EGCG/AA NPs treatment also mitigated neuroinflammation and prevented neuronal loss. Conclusion: NP encapsulation enhances therapeutic robustness of EGCG in this model of HD symptomatology. Together with our previous findings, this highlights the potential of EGCG/AA NPs in the symptomatic treatment of neurodegenerative diseases.

Influence of 3-nitropropionic acid on physiological and behavioral responses in zebrafish larvae and adults

Long-term treatment with 3-nitropropionic acid (3-NPA), a toxin derived from plants and fungi, may reproduce symptoms and biochemical characteristics of Huntington's disease (HD). Our study evaluated the effects of 3-NPA on the physiological and behavioral responses in zebrafish larvae and adults. Larvae exposed to 0.1, 0.2, or 0.5 mM 3-NPA exhibited an increase in heart rate at 2- and 5-days post-fertilization (dpf). There was a decrease in the ocular distance at 5 dpf with 0.05 mM 3-NPA treatment. However, 3-NPA did not alter larval locomotor parameters. Adult zebrafish received 3-NPA intraperitoneal injections (a total of seven injections at doses 10, 20, or 60 mg/kg every 96 h) and showed a decrease in body weight , locomotion and aggressive behavior. No changes were observed in anxiety-like behavior and social interaction between 3-NPA-exposed animals and control groups. However, 3-NPA-treated animals (at 60 mg/kg) demonstrated impaired long-term aversive memory. Overall, 3-NPA exposure induced morphological and heart rate alterations in zebrafish larvae. Additionally, our study showed behavioral changes in zebrafish that were submitted to long-term 3-NPA treatment, which could be related to HD symptoms.

Dapagliflozin improves behavioral dysfunction of Huntington's disease in rats via inhibiting apoptosis-related glycolysis

AIMS

Huntington's disease is a rare neurodegenerative disorder which is associated with defected glucose metabolism with consequent behavioral disturbance including memory and locomotion. 3-nitropropionic acid (3-NP) can cause, in high single dose, an acute striatal injury/Huntington's disease. Dapagliflozin, which is one of the longest duration of action of SGLTIs family, may be able to diminish that injury and its resultant behavioral disturbances.

MATERIAL AND METHODS

Forty rats were divided into four groups (n = 10 in each group): normal control group (CTRL), dapagliflozin (CTRL + DAPA) group, 3-nitropropionic acid (3-NP) group, and dapagliflozin plus 3-nitropropionic acid (DAPA + 3-NP) group. Behavioral tests (beam walking test, hanging wire test, limb withdrawal test, Y-maze spontaneous alteration, elevated plus maze) were performed with evaluating neurological scoring. In striatum, neurotransmitters (glutamate, aspartate, GABA, ACh and AChE activity) were measured. In addition, apoptosis and glycolysis markers (NF-κB, Cyt-c, lactate, HK-II activity, P53, calpain, PEA15 and TIGAR) were determined. Inflammation (IL-1β, IL-6, IL-8 and TNF-α) and autophagy (beclin-1, LC3 and DRAM) indicators were measured. Additionally, histopathological screening was conducted.

KEY FINDINGS

3-Nitropropionic acid had the ability to perturb the neurotransmission which was reflected in impaired behavioral outcome. All of glycolysis, apoptosis and inflammation markers were elevated after 3-NP acute intoxication but autophagy parameters, except DRAM, were reduced. However, DAPA markedly reversed the abovementioned parameters.

SIGNIFICANCE

Dapagliflozin demonstrated anti-glycolytic, anti-apoptotic, anti-inflammatory and autophagic effects on 3-NP-damaged striatal cells and promoted the behavioral outcome.

Embelin averts MPTP-induced dysfunction in mitochondrial bioenergetics and biogenesis via activation of SIRT1

Parkinson's disease (PD) is a chronic neurodegenerative disease characterized by the death of dopamine neurons of Substantia nigra pars compacta (SNpc) leading to motor deficits. Amongst the mechanisms proposed, mitochondrial dysfunction, reduced complex-I and PGC1α levels were found to correlate with the pathology of PD. As embelin is a natural product with structural resemblance to ubiquinone, exhibits mitochondrial uncoupling and antioxidant effects, in the present study, we sought to examine its role in the mechanisms mediating PD. Results indicate that embelin protects from MPP⁺-induced oxidative stress and apoptosis in a time and dose-dependent manner in N27 dopaminergic cells. Cells treated with embelin exhibited increased levels of pAMPK, SIRT1 and PGC1α leading to enhanced mitochondrial biogenesis. Though treatment of cells with MPP⁺ also increased pAMPK levels, but, SIRT1 and PGC1α levels decreased substantially, possibly due to the block in the mitochondrial electron transport chain and reduced NAD/NADH levels. The mitochondrial uncoupling effects of embelin leading to increased NAD/NADH levels followed by enhanced SIRT1, PGC1α and mitochondrial biogenesis were found to confer embelin mediated protection as treatment of cells with SIRT1 inhibitor or siRNA nullified this effect. Embelin (10 mg/kg) also conferred protection in vivo in MPTP mouse model of PD, wherein, MPTP-induced loss of TH staining, reduced striatal dopamine and markers of mitochondrial biogenesis pathway were averted by embelin.