Fermentation enhances Ginkgo biloba protective role on gamma-irradiation induced neuroinflammatory gene expression and stress hormones in rat brain

Comprehensive Exploration of the Neuroprotective Mechanisms of Ginkgo biloba Leaves in Treating Neurological Disorders

Neurological disorders (NDs) are diseases that seriously affect the health of individuals worldwide, potentially leading to a significant reduction in the quality of life for patients and their families. Herbal medicines have been widely used in the treatment of NDs due to their multi-target and multi-pathway features. Ginkgo biloba leaves (GBLs), one of the most popular herbal medicines in the world, have been demonstrated to present therapeutic effects on NDs. However, the pharmacological mechanisms of GBLs in the treatment of neurological disorders have not been systematically summarized. This study aimed to summarize the molecular mechanism of GBLs in treating NDs from the cell models, animal models, and clinical trials of studies. Four databases, i.e., PubMed, Google Scholar, CNKI, and Web of Science were searched using the following keywords: "Ginkgo biloba", "Ginkgo biloba extract", "Ginkgo biloba leaves", "Ginkgo biloba leaves extract", "Neurological disorders", "Neurological diseases", and "Neurodegenerative diseases". All items meeting the inclusion criteria on the treatment of NDs with GBLs were extracted and summarized. Additionally, PRISMA 2020 was performed to independently evaluate the screening methods. Out of 1385 records in the database, 52 were screened in relation to the function of GBLs in the treatment of NDs; of these 52 records, 39 were preclinical trials and 13 were clinical studies. Analysis of pharmacological studies revealed that GBLs can improve memory, cognition, behavior, and psychopathology of NDs and that the most frequently associated GBLs are depression, followed by Alzheimer's disease, stroke, Huntington's disease, and Parkinson's disease. Additionally, the clinical studies of depression, AD, and stroke are the most common, and most of the remaining ND data are available from in vitro or in vivo animal studies. Moreover, the possible mechanisms of GBLs in treating NDs are mainly through free radical scavenging, anti-oxidant activity, anti-inflammatory response, mitochondrial protection, neurotransmitter regulation, and antagonism of PAF. This is the first paper to systematically and comprehensively investigate the pharmacological effects and neuroprotective mechanisms of GBLs in the treatment of NDs thus far. All findings contribute to a better understanding of the efficacy and complexity of GBLs in treating NDs, which is of great significance for the further clinical application of this herbal medicine.

Biological Activity of Fermented Plant Extracts for Potential Dermal Applications

Fermented plant extracts (FPEs) are functional liquids formed as a result of the fermentation of fresh plants by microorganisms, mainly bacteria and fungi. The appropriate selection of plants, microorganism strains, and conditions under which the fermentation process is carried out is very important in terms of obtaining a suitable matrix of biologically active compounds with different biological properties. The purpose of this review is to provide verified data on the current knowledge acquired regarding the biological activity of FPEs for cosmetic use and dermal applications. The antioxidant, antimicrobial, anti-inflammatory, anti-melanogenic, and wound-healing activity of FPEs, as well as their potential dermal applications, will be described.

Potentialities of Ginkgo extract on toxicants, toxins, and radiation: a critical review

Exposure to toxins is a severe threat to human health and life in today's developing and industrialized world. Therefore, identifying a protective chemical could be valuable and fascinating in this case. The purpose of this article was to bring together thorough review of studies on Ginkgo biloba to aid in the creation of ways for delivering its phytoconstituents to treat toxicants and radiation. This review gathered and evaluated studies on the defensive impact of Ginkgo biloba extract (GBE) against toxicities caused by toxic chemical agents (such as lead, cadmium, and aluminum), natural toxins (for example, lipopolysaccharide-induced toxicity and damage, gossypol, latadenes, and lotaustralin), and radiation (for example, gamma, ultra-violet, and radio-frequency radiation). According to this review, GBE has a considerable therapeutic effect by influencing specific pathophysiological targets. Furthermore, GBE has antioxidant, anti-inflammatory, anti-apoptotic, and antigenotoxicity properties against various toxicities. These are due to flavone glycosides (primarily isorhamnetin, kaempferol, and quercetin) and terpene trilactones (ginkgolides A, B, C, and bilobalide) that aid GBEs' neutralizing effect against radiation and toxins by acting independently or synergistically. This will serve as a reference for the functional food, cosmetic, and pharmaceutical industries worldwide.

Microglia as Therapeutic Target for Radiation-Induced Brain Injury

Radiation-induced brain injury (RIBI) after radiotherapy has become an increasingly important factor affecting the prognosis of patients with head and neck tumor. With the delivery of high doses of radiation to brain tissue, microglia rapidly transit to a pro-inflammatory phenotype, upregulate phagocytic machinery, and reduce the release of neurotrophic factors. Persistently activated microglia mediate the progression of chronic neuroinflammation, which may inhibit brain neurogenesis leading to the occurrence of neurocognitive disorders at the advanced stage of RIBI. Fully understanding the microglial pathophysiology and cellular and molecular mechanisms after irradiation may facilitate the development of novel therapy by targeting microglia to prevent RIBI and subsequent neurological and neuropsychiatric disorders.

Control of Neuroinflammation through Radiation-Induced Microglial Changes

Microglia, the innate immune cells of the central nervous system, play a pivotal role in the modulation of neuroinflammation. Neuroinflammation has been implicated in many diseases of the CNS, including Alzheimer's disease and Parkinson's disease. It is well documented that microglial activation, initiated by a variety of stressors, can trigger a potentially destructive neuroinflammatory response via the release of pro-inflammatory molecules, and reactive oxygen and nitrogen species. However, the potential anti-inflammatory and neuroprotective effects that microglia are also thought to exhibit have been under-investigated. The application of ionising radiation at different doses and dose schedules may reveal novel methods for the control of microglial response to stressors, potentially highlighting avenues for treatment of neuroinflammation associated CNS disorders, such as Alzheimer's disease and Parkinson's disease. There remains a need to characterise the response of microglia to radiation, particularly low dose ionising radiation.

Flavonoids, the Family of Plant-derived Antioxidants making inroads into Novel Therapeutic Design against IR-induced Oxidative Stress in Parkinson's Disease

Background:

Ionizing radiation from telluric sources is unceasingly an unprotected pitfall to humans. Thus, the foremost contributors to human exposure are global and medical radiations. Various evidences assembled during preceding years reveal the pertinent role of ionizing radiation-induced oxidative stress in the progression of neurodegenerative insults, such as Parkinson’s disease, which have been contributing to increased proliferation and generation of reactive oxygen species.

Objective:

This review delineates the role of ionizing radiation-induced oxidative stress in Parkinson’s disease and proposes novel therapeutic interventions of flavonoid family, offering effective management and slowing down the progression of Parkinson’s disease.

Methods:

Published papers were searched in MEDLINE, PubMed, etc., published to date for in-depth database collection.

Results:

The oxidative damage may harm the non-targeted cells. It can also modulate the functions of the central nervous system, such as protein misfolding, mitochondria dysfunction, increased levels of oxidized lipids, and dopaminergic cell death, which accelerate the progression of Parkinson’s disease at the molecular, cellular, or tissue levels. In Parkinson’s disease, reactive oxygen species exacerbate the production of nitric oxides and superoxides by activated microglia, rendering death of dopaminergic neuronal cell through different mechanisms.

Conclusion:

Rising interest has extensively engrossed in the clinical trial designs based on the plant-derived family of antioxidants. They are known to exert multifarious impact on neuroprotection via directly suppressing ionizing radiation-induced oxidative stress and reactive oxygen species production or indirectly increasing the dopamine levels and activating the glial cells.

Review of the Efficacy and Mechanisms of Traditional Chinese Medicines as a Therapeutic Option for Ionizing Radiation Induced Damage

Ionizing radiation damage refers to acute, delayed, or chronic tissue damage associated with ionizing radiation. Specific or effective therapeutic options for systemic injuries induced by ionizing radiation have not been developed. Studies have shown that Chinese herbal Medicine or Chinese Herbal Prescription exhibit preventive properties against radiation damage. These medicines inhibit tissue injuries and promote repair with very minimal side effects. This study reviews traditional Chinese herbal medicines and prescriptions with radiation protective effects as well as their mechanisms of action. The information obtained will guide the development of alternative radioprotectants.

The impact of citicoline on brain injury in rats subjected to head irradiation

Hazard and risk associated with the use of radiotherapy play a crucial role in brain injury with interference via the neuroendocrine activity of the cancer survivors, and there is no effective preventive strategy. We conducted this study to assess the effect of citicoline in biosynthesis variants occurring in the cerebral cortex of rats in response to head γ-irradiation. Bio-analysis includes MDA, 8-OHdG, and NO as oxidation indicators; total antioxidant activity; the inflammatory factors TNF-α, IL-1β, and amyloid-β 42 levels; the caspase-3 cell death marker; IGF-I; serum hormones including GH, ACTH, FSH, and LH; and the neurotransmitters acetylcholine, dopamine, and serotonin. We exposed animals to 10 Gy head gamma irradiation followed by citicoline treatment and sustained for 30 days. The animals were sacrificed at the 3rd and 30th day post-irradiation. Citicoline mechanism has been linked to potent radical reduced ability counteracting the oxidative stress-mediated inflammation and apoptosis. Citicoline treatment has normalized the altering recorded in serum hormones associated with a significant modulation in the levels of IGF-1/PI3K/AKT factors. Such improvements have been concomitant with regulated neurotransmitter levels. We could conclude that citicoline may safely be supplemented to avoid both short- and long-term damages to the neuroendocrine disturbances, oxidative stress, inflammation, and apoptosis induced by head irradiation.

Oral Supplements of <i>Ginkgo biloba</i> Extract Alleviate Neuroinflammation, Oxidative Impairments and Neurotoxicity in Rotenone-Induced Parkinsonian Rats

BACKGROUND

Ginkgo biloba extract (GbE) is known to contain several bioactive compounds and exhibits free radical scavenging activity. Parkinson's Disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons and is associated with oxidative stress, neuroinflammation and apoptosis.

OBJECTIVE

The current study aimed to investigate the neuroprotective effect of GbE in a rat model of PD induced by rotenone (ROT; a neurotoxin).

METHODS

Twenty-four male albino rats were randomly divided into four groups of six rats each: normal control, GbE treated, toxin control (ROT treated) and GbE+ROT group.

RESULTS

Oral administration of ROT (2.5 mg/kg b.w.) for 50 days caused an increased generation of lipid peroxidation products and significant depletion of reduced glutathione, total thiol content and activities of enzymatic antioxidants, i.e., superoxide dismutase and glutathione peroxidase in the brains of treated rats. Furthermore, ROT caused an elevation in acetylcholinesterase, interleukin-1β, interleukin- 6 and tumor necrosis factor-α and a significant reduction in dopamine in the stratum and substantia nigra. Immunohistochemical results illustrated that ROT treatment reduced the expression of tyrosine hydroxylase (TH). GbE treatment (150 mg/kg b.w./day) significantly reduced the elevated oxidative stress markers and proinflammatory cytokines and restored the reduced antioxidant enzyme activities, DA level and TH expression. These results were confirmed by histological observations that clearly indicated a neuroprotective effect of GbE against ROT-induced PD.

CONCLUSION

GbE mitigated ROT-induced PD via the inhibition of free-radical production, scavenging of ROS, and antioxidant enhancement.

Nicotine encourages oxidative stress and impairment of rats' brain mitigated by Spirulina platensis lipopolysaccharides and low-dose ionizing radiation

Nicotine is a psychoactive alkaloid of tobacco, which is ingested during cigarettes or electronic cigarette smoking. Extensive consumption of nicotine induced oxidative stress. Accordingly, it is implicated in many pathophysiology brain disorders and triggers neurodegeneration. In this study, we investigated the protective role of Spirulina platensis-lipopolysaccharides (S.LPS) and the low dose-ionizing radiation (LD-IR) against the induced neurotoxicity in the rats' brain due to the prolonged administration of high nicotine levels. Rats treated with nicotine for two months showed alterations in the oxidative stress markers (malondialdehyde (MDA), reduced glutathione (GSH) and oxidized glutathione disulfide (GSSG)), antioxidant enzymes (superoxide dismutase (SOD), catalase (Cat), glutathione enzymes (GPx and GST)) as well as several pro-inflammatory markers (Tumor Necrosis Factor-alpha (TNF-α), Interleukin-17 (IL-17), and Nuclear Factor-kappa B (NF-κB)), and induced apoptosis through Caspase-3 activity. Nicotine also upregulated the mRNA gene expression of cytochrome P450 enzymes (CYP2B1 and CYP2E1), Cyclin-dependent kinase 5 (CDK5), Toll-Like Receptor 4 (TLR4), and phospho-Tau (p-Tau) protein expression. Besides, it downregulated the alpha-7 nicotinic receptor (α7nAChR) mRNA gene expression accompanied by a decline in the calcium (Ca2+) level. S.LPS exhibited antioxidant, anti-inflammatory, anti-apoptotic and neuroprotective activities, which counteracting the detrimental effects of chronic nicotine administration. LD-IR demonstrated comparable effects to S.LPS. Exposure of rats to LD-IR enhanced the neuroprotective effects of S.LPS against nicotine toxicity. The light microscopic examination of the brain tissues was in agreement with the biochemical investigations. These findings display that S.LPS and LD-IR mitigated the oxidative stress and the impairment of rats' brain induced by nicotine, due to regulation of the mRNA gene expression of cytochrome P450 enzymes (CYP2B1 and CYP2E1) and the signaling pathway of Tau protein phosphorylation.

Immunomodulatory effect of new quinolone derivative against cisplatin/gamma radiation-induced renal and brain toxicity in mice

Treatment of cancer often requires exposure to radiation, which has several limitations involving non-specific toxicity toward normal cells, reducing the efficacy of treatment. Recent studies synthesize new quinolone derivatives to satisfy other purposes such as treatment of inflammatory and malignant diseases. The main purpose of the present study is to evaluate the effect of a new quinolone derivative; 2-(1-Ethyl-4-hydroxy-2-oxo-1,2-dihydroquinolin-3-yl)-2-oxoacetic acid (EHQA) and its possible mechanism against gamma radiation (IRR) and cisplatin (Cis) induced nephrotoxicity and neurotoxicity in mice. The structure of the newly synthesized quinolone derivative was elucidated by microanalytical and spectral data, which were found consistent with the assigned structures. Exposure to Cis and IRR significantly induced renal damage manifested by a significant increase in levels of urea and creatinine. Moreover, the exposure to both Cis and IRR significantly decreased the levels of anti-apoptotic protein; Bcl-2 in both renal and brain tissue homogenate accompanied by activation of an inflammatory marker; IL-17. Immunophenoting results showed an activation of T- lymphocytes marker; CD3 and B-lymphocytes marker; CD19. Interperitonial administration of EHQA significantly ameliorated the above-mentioned parameters. Overall, the present results indicated that EHQA is a promising anti-inflammatory and anti-apoptotic agent. From the obtained results it can be concluded that EHQA could be a candidate as immunomodulatory agents. Further studies are required to establish its molecular mechanism.

Ginger fermented with Schizosaccharomyces pombe alleviates memory impairment via protecting hippocampal neuronal cells in amyloid beta1-42 plaque injected mice

Ginger, which has been widely used for dietary condiment, has been reported to improve memory dysfunction in an animal model of Alzheimer's disease (AD). Recently, a few trials have been carried out to enhance the effects of ginger by improving the bioavailability of its relevant components via fermentation. Some reports have suggested that the fermented ginger has the ability to affect the AD in vitro systems; however, its anti-amnesic effects on an in vivo model still remain to be investigated. In the present study, we aimed to investigate the neuroprotective effects of ginger fermented with Schizosaccharomyces pombe (FG) in the in vivo models of AD. The neuroprotective effects were investigated by employing behavioral, western blotting, and immunohistochemical assays. The administration of FG improved recognition memory, impaired by scopolamine injection, than that of non-fermented ginger. In addition, FG ameliorated memory impairment in amyloid beta1-42 (Aβ1-42) plaque-injected mice via protecting neuronal cells in the CA3 area of the mouse hippocampus. Moreover, FG reinstated the pre- and postsynaptic protein levels decreased by Aβ1-42 plaque-toxicity. Overall, these data suggest that FG attenuates memory impairment in Aβ1-42 plaque-induced AD mice through inhibition of neuronal cell loss and synaptic disruption.

Anti-inflammatory effects of Ginkgo biloba extract against trimethyltin-induced hippocampal neuronal injury

BACKGROUND

Despite the immense neuromodulatory potentials of Ginkgo biloba extract as a memory enhancer, its underlying mechanism seems inadequate particularly with regard to its anti-inflammatory properties.

AIM

The objective of the present study is to investigate the protective potentials of Ginkgo biloba extract (GBE) against hippocampal neuronal injury induced by trimethyltin (TMT), a potent neurotoxicant.

METHODS

Male SD rats were administered trimethyltin (8.5 mg kg^-1 b.wt) single intraperitoneal (i.p.) injection, followed by Ginkgo biloba extract (100 mg kg^-1 b.wt i.p) for 21 days.

RESULTS

The co-administration of GBE with TMT showed marked improvement in cognitive functions. Concomitantly, there was a significant decrease in oxidative stress as evident by reduction in MDA and total ROS levels. In addition, there was a marked suppression of astrocyte activation (GFAP), transcription factor NFκB and proinflammatory cytokines (TNF-α, IL-1α, 1L-6), which were found to be elevated by TMT administration. Histopathological observations showed remarkable improvement in hippocampal neuronal injury in the conjunctive group.

CONCLUSION

Therefore, it is suggested that Ginkgo biloba extract is an effective agent against trimethyltin-induced hippocampal neuronal loss owing to its antioxidative as well as anti-inflammatory properties.

Modulatory effects of new curcumin analogues on gamma-irradiation - Induced nephrotoxicity in rats

In the present study, a new series of 2-amino-pyran-3-carbonitrile derivatives of curcumin 2-7 have been synthesized via one-pot simple and efficient protocol, involving the reaction of curcumin 1 with substituted-benzylidene-malononitrile to modify the 1,3-diketone moiety. The structures of the synthesized compounds 2-7 were elucidated by microanalytical and spectral data, which were found consistent with the assigned structures. The nephroprotective mechanism of these new curcumin analogues was evaluated on the post-gamma-irradiation (7 Gy) - induced nephrotoxicity in rats. Activation of Nrf2 by these curcumin analogues is responsible for the amendment of the antioxidant status, impairment of NF-κB signal, thus attenuate the nephrotoxicity induced post-γ-irradiation exposure. 4-Chloro-phenyl curcumin analogue 7 showed the most potent activity. In conclusion, the results of the present study demonstrate a promising role of these new curcumin analogues to attenuate the early symptoms of nephrotoxicity induced by γ-irradiation in rats via activation of Nrf2 gene expression. These new curcumin analogues need further toxicological investigations to assess their therapeutic index.

The impact of high and low dose ionising radiation on the central nervous system

Responses of the central nervous system (CNS) to stressors and injuries, such as ionising radiation, are modulated by the concomitant responses of the brains innate immune effector cells, microglia. Exposure to high doses of ionising radiation in brain tissue leads to the expression and release of biochemical mediators of ‘neuroinflammation’, such as pro-inflammatory cytokines and reactive oxygen species (ROS), leading to tissue destruction. Contrastingly, low dose ionising radiation may reduce vulnerability to subsequent exposure of ionising radiation, largely through the stimulation of adaptive responses, such as antioxidant defences. These disparate responses may be reflective of non-linear differential microglial activation at low and high doses, manifesting as an anti-inflammatory or pro-inflammatory functional state. Biomarkers of pathology in the brain, such as the mitochondrial Translocator Protein 18 kDa (TSPO), have facilitated in vivo characterisation of microglial activation and ‘neuroinflammation’ in many pathological states of the CNS, though the exact function of TSPO in these responses remains elusive. Based on the known responsiveness of TSPO expression to a wide range of noxious stimuli, we discuss TSPO as a potential biomarker of radiation-induced effects.

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Ionising radiation can modulate responses of microglial cells in the CNS.

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High doses can induce ROS formation, oxidative stress and neuroinflammation.

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Low doses can mitigate tissue damage via antioxidant defences.

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TSPO as a potential biomarker and modulator of radiation induced effects in the CNS.

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Non-linear differential microglial activation to high and low doses is proposed.