Naringin Abrogates Cisplatin-Induced Cognitive Deficits and Cholinergic Dysfunction Through the Down-Regulation of AChE Expression and iNOS Signaling Pathways in Hippocampus of Aged Rats

Psychopharmacological interaction of alcohol and posttraumatic stress disorder: Effective action of naringin

Posttraumatic stress disorder (PTSD) and alcohol use disorder (AUD) are prevalently co-occurring, important risk factors for a broad array of neuropsychiatric diseases. To date, how these two contrastive concomitant pairs increase the risk of neuropsychiatric states, notably exacerbating PTSD-related symptoms, remains unknown. Moreover, pharmacological interventions with agents that could reverse PTSD-AUD comorbidity, however, remained limited. Hence, we investigated the neuroprotective actions of naringin in mice comorbidly exposed to PTSD followed by repeated ethanol (EtOH)-induced AUD. Following a 7-day single-prolong-stress (SPS)-induced PTSD in mice, binge/heavy drinking, notably related to AUD, was induced in the PTSD mice with every-other-day ethanol (2 g/kg, p.o.) administration, followed by daily treatments with naringin (25 and 50 mg/kg) or fluoxetine (10 mg/kg), from days 8-21. PTSD-AUD-related behavioral changes, alcohol preference, hypothalamic-pituitary-adrenal (HPA)-axis dysfunction-induced neurochemical alterations, oxidative/nitrergic stress, and inflammation were examined in the prefrontal-cortex, striatum, and hippocampus. PTSD-AUD mice showed aggravated anxiety, spatial-cognitive, social impairments and EtOH intake, which were abated by naringin, similar to fluoxetine. Our assays on the HPA-axis showed exacerbated increased corticosterone release and adrenal hypertrophy, accompanied by marked dopamine and serotonin increase, with depleted glutamic acid decarboxylase enzyme in the three brain regions, which naringin, however, reversed, respectively. PTSD-AUD mice also showed increased TNF-α, IL-6, malondialdehyde and nitrite levels, with decreased antioxidant elements in the prefrontal-cortex, striatum, and hippocampus compared to SPS-EtOH-mice, mainly exacerbating catalase and glutathione decrease in the hippocampus relative SPS-mice. These findings suggest that AUD exacerbates PTSD pathologies in different brain regions, notably comprising neurochemical dysregulations, oxidative/nitrergic and cytokine-mediated inflammation, with HPA dysfunction, which were, however, revocable by naringin.

Effects of protocatechuic acid against cisplatin-induced neurotoxicity in rat brains: an experimental study

Aims/Objectives: Cisplatin (CIS) is widely used in the treatment of various malignant tumors. The aim of study is to determine the potential protective effects of protocatechuic acid (PCA) on the brain in neurotoxicity induced by CIS in rats.Materials and methods: Forty rats were divided into four groups: 1-Control group: 2- PCA group: PCA was administered orally at a dose of 100 mg/kg/day for 5 weeks. 3-CIS group: 5 mg/kg/week of CIS was administered intraperiteonally 4-PCA + CIS group: The rats were given PCA orally daily for 5 weeks and CIS of 5 mg/kg/week. The brain tissues were used for histopathological examinations and for total antioxidant capacity (TAC), total oxidative state (TOS), oxidative stress index (OSI), tumornecrosis factor-alpha (T NF-α), interleukin 6 (IL-6) Interleukin 1 beta (IL-1β), acetylcholinesterase (AChE), glutamate, gamma aminobutyric acid (GABA), dopamine analyzes in ELISA. WBC, RBC, hemoglobin and hematocrit levels were measured.Results: PCA + CIS group compared to CIS group TOS, OSI, T NF-α, IL-6, IL-1β, AChE, glutamate, WBC levels decreased significantly, while TAC and GABA levels increased statistically significant. With this study, P CA corrected the deterioration in the oxidant / antioxidant status, suppressed neuro-inflammation, decreased AChE activity, partially normalized neurotransmitters, and decreased the increased WBC count. Necrosis seen in the CIS group in histopathological examinations was never seen in the PCA + CIS group.Conclusions: PCA may provide therapeutic benefit when used in conjunction with CIS.

Natural products for the treatment of chemotherapy-related cognitive impairment and prospects of nose-to-brain drug delivery

Chemotherapy-related cognitive deficits (CRCI) as one of the common adverse drug reactions during chemotherapy that manifest as memory, attention, and executive function impairments. However, there are still no effective pharmacological therapies for the treatment of CRCI. Natural compounds have always inspired drug development and numerous natural products have shown potential therapeutic effects on CRCI. Nevertheless, improving the brain targeting of natural compounds in the treatment of CRCI is still a problem to be overcome at present and in the future. Accumulated evidence shows that nose-to-brain drug delivery may be an excellent carrier for natural compounds. Therefore, we reviewed natural products with potential anti-CRCI, focusing on the signaling pathway of these drugs' anti-CRCI effects, as well as the possibility and prospect of treating CRCI with natural compounds based on nose-to-brain drug delivery in the future. In conclusion, this review provides new insights to further explore natural products in the treatment of CRCI.

Chemotherapy-Mediated Neuronal Aberration

Chemotherapy is a life-sustaining therapeutic option for cancer patients. Despite the advancement of several modern therapies, such as immunotherapy, gene therapy, etc., chemotherapy remains the first-line therapy for most cancer patients. Along with its anti-cancerous effect, chemotherapy exhibits several detrimental consequences that restrict its efficacy and long-term utilization. Moreover, it effectively hampers the quality of life of cancer patients. Cancer patients receiving chemotherapeutic drugs suffer from neurological dysfunction, referred to as chemobrain, that includes cognitive and memory dysfunction and deficits in learning, reasoning, and concentration ability. Chemotherapy exhibits neurotoxicity by damaging the DNA in neurons by interfering with the DNA repair system and antioxidant machinery. In addition, chemotherapy also provokes inflammation by inducing the release of various pro-inflammatory cytokines, including NF-kB, IL-1β, IL-6, and TNF-α. The chemotherapy-mediated inflammation contributes to chemobrain in cancer patients. These inflammatory cytokines modulate several growth signaling pathways and reactive oxygen species homeostasis leading to systemic inflammation in the body. This review is an effort to summarize the available information which discusses the role of chemotherapy-induced inflammation in chemobrain and how it impacts different aspects of therapeutic outcome and the overall quality of life of the patient. Further, this article also discusses the potential of herbal-based remedies to overcome chemotherapy-mediated neuronal toxicity as well as to improve the quality of life of cancer patients.

Nose to brain delivery of naringin-loaded chitosan nanoparticles for potential use in oxaliplatin-induced chemobrain in rats: impact on oxidative stress, cGAS/STING and HMGB1/RAGE/TLR2/MYD88 inflammatory axes

OBJECTIVES

Oxaliplatin induces chemobrain in cancer patients/survivors. Nutraceutical naringin has antioxidant and anti-inflammatory properties with low oral bioavailability. Our aim was to formulate naringin in chitosan nanoparticles for nose to brain delivery and assess its neuroprotective effect against oxaliplatin-induced chemobrain in rats.

METHODS

Naringin chitosan nanoparticles were prepared by ionic gelation. Rats were administered oral naringin (80 mg/kg), intranasal naringin (0.3 mg/kg) or intranasal naringin-loaded chitosan nanoparticles (0.3 mg/kg). Naringin's neuroprotective efficacy was assessed based on behavioral tests, histopathology, and measuring oxidative stress and inflammatory markers.

RESULTS

Selected nanoparticles formulation showed drug loading of 5%, size of 150 nm and were cationic. Intranasal naringin administration enhanced memory function, inhibited hippocampal acetylcholinesterase activity, and corrected oxaliplatin-induced histological changes. Moreover, it reduced malondialdehyde and elevated reduced glutathione hippocampal levels. Furthermore, it decreased levels of inflammatory markers: NF-kB and TNF-α by 1.25-fold. Upstream to this inflammatory status, intranasal naringin downregulated the hippocampal protein levels of two pathways: cGAS/STING and HMGB1/RAGE/TLR2/MYD88.

CONCLUSION

Intranasal naringin-loaded chitosan nanoparticles showed superior amelioration of oxaliplatin-induced chemobrain in rats at a dose 267-fold lower to that administered orally. The potential involvement of cGAS/STING and HMGB1/RAGE/TLR2/MYD88 pathways in the mechanistic process of either oxaliplatin-induced chemobrain or naringin-mediated neuroprotection was evidenced.

Vildagliptin restores cognitive function and mitigates hippocampal neuronal apoptosis in cisplatin-induced chemo-brain: Imperative roles of AMPK/Akt/CREB/ BDNF signaling cascades

Cisplatin (CP) is a broad-spectrum antineoplastic agent used to treat many human cancers. Nonetheless, most patients receiving CP suffer from cognitive deficits, a phenomenon termed "chemo-brain". Recently, vildagliptin (Vilda), a DPP-4 inhibitor, has demonstrated promising neuroprotective properties against various neurological diseases. Therefore, the present study aims to investigate the potential neuroprotective properties of Vilda against CP-induced neurotoxicity and elucidate the underlying molecular mechanisms. Chemo-brain was induced in Sprague-Dawley rats by i.p injection of CP at a dose of 5 mg/kg once weekly for four weeks. Vilda was administered daily at a dose (10 mg/kg; P.O) for four weeks. The results revealed that Vilda restored the cognitive function impaired by CP, as assessed by the Morris water maze, Y-maze, and passive avoidance tests. Moreover, Vilda alleviated the CP-induced neurodegeneration, as shown by toluidine blue staining, besides markedly reduced amyloid plaque deposition, as evidenced by Congo red staining. Notably, Vilda boosted cholinergic neurotransmission through the downregulation of the acetylcholinesterase enzyme. In addition, the neuroprotective mechanisms of Vilda include diminishing oxidative stress by reducing MDA levels while raising GSH levels and SOD activity, repressing neuronal apoptosis as shown by elevated Bcl-2 levels together with diminished Bax and caspase-3 expressions, inhibiting neuroinflammation as shown by decreased GFAP expression, and finally boosting hippocampal neurogenesis and survival by upregulating expressions of BDNF and PCNA. These effects were mainly mediated by activating AMPK/Akt/CREB signaling cascades. In summary, Vilda can be considered a promising candidate for guarding against CP-induced chemo-brain and neurodegeneration, thus improving the quality of life of cancer patients.

Agomelatine attenuates cisplatin-induced cognitive impairment via modulation of BDNF/TrkB signaling in rat hippocampus

Cisplatin is a drug used effectively in the treatment of malignant tumors. However, cisplatin has many side effects, including cognitive impairment. Agomelatine, a synthetic melatonin analogue, is an important antidepressant. Increasing evidence has shown that agomelatine may be a potential neuroprotective agent. The aim of this study was to investigate the effect of agomelatine on learning and memory functions in cisplatin-induced cognitive impairment in a rat model. Male rats were administered agomelatine and cisplatin for 4 weeks. Neurobehavioral tests were performed at the end of the 4th week. After behavioral tests, rats were euthanized and BDNF, TNF, IL-1β, MDA and GSH levels were measured in hippocampal homegenates by ELISA. In addition, nNOS and TrkB receptor activity were measured immunohistochemically. The results showed that agomelatine significantly improved cognitive functions in spatial memory tests in rats with cisplatin-induced cognitive impairment. In addition, agomelatine treatment positively affected the discrimination index (DI). On the other hand, agomelatine treatment elevated cisplatin-suppressed hippocampal BDNF levels. Agomelatine treatment reduced cisplatin-induced neuroinflammation by suppressing TNF and IL-1β levels. Similarly, agomelatine reduced oxidative stress in the hippocampus. Histological findings showed that agomelatine treatment reduced pyramidal neuron damage in hippocampal DG, CA1 and CA3. Cisplatin increased nNOS and TrkB positivity in DG, CA1 and CA3 neurons compared to control. In contrast, agomelatine treatment decreased both nNOS and TrkB positive scores. These findings indicate that agomelatine reduces cisplatin-related cognitive impairment by exerting anti-inflammatory action and possibly by the modulation of the BDNF/TrkB/nNOS pathways in the hippocampus.

Antioxidant, Wound Healing Potential and In Silico Assessment of Naringin, Eicosane and Octacosane

1. Diabetic chronic wounds, mainly foot ulcers, constitute one of the most common complications of poorly managed diabetes mellitus. The most typical reasons are insufficient glycemic management, latent neuropathy, peripheral vascular disease, and neglected foot care. In addition, it is a common cause of foot osteomyelitis and amputation of the lower extremities. Patients are admitted in larger numbers attributable to chronic wounds compared to any other diabetic disease. In the United States, diabetes is currently the most common cause of non-traumatic amputations. Approximately five percent of diabetics develop foot ulcers, and one percent require amputation. Therefore, it is necessary to identify sources of lead with wound-healing properties. Redox imbalance due to excessive oxidative stress is one of the causes for the development of diabetic wounds. Antioxidants have been shown to decrease the progression of diabetic neuropathy by scavenging ROS, regenerating endogenous and exogenous antioxidants, and reversing redox imbalance. Matrix metalloproteinases (MMPs) play vital roles in numerous phases of the wound healing process. Antioxidant and fibroblast cell migration activity of Marantodes pumilum (MP) crude extract has previously been reported. Through their antioxidant, epithelialization, collagen synthesis, and fibroblast migration activities, the authors hypothesise that naringin, eicosane and octacosane identified in the MP extract may have wound-healing properties. 2. The present study aims to identify the bioactive components present in the dichloromethane (DCM) extract of M. pumilum and evaluate their antioxidant and wound healing activity. Bioactive components were identified using LCMS, HPTLC and GCMS. Excision wound on STZ-induced diabetic rat model, human dermal fibroblast (HDF) cell line and colorimetric antioxidant assays were used to evaluate wound healing and antioxidant activities, respectively. Molecular docking and pkCMS software would be utilised to predict binding energy and affinity, as well as ADME parameters. 3. Naringin (NAR), eicosane (EIC), and octacosane (OCT) present in MP displayed antioxidant action and wound excision closure. Histological examination HDF cell line demonstrates epithelialization, collagen production, fibroblast migration, polymorphonuclear leukocyte migration (PNML), and fibroblast movement. The results of molecular docking indicate a substantial attraction and contact between MMPs. pkCMS prediction indicates inadequate blood-brain barrier permeability, low toxicity, and absence of hepatotoxicity. 4. Wound healing properties of (NEO) naringin, eicosane and octacosane may be the result of their antioxidant properties and possible interactions with MMP.

Naringin and Naringenin Polyphenols in Neurological Diseases: Understandings from a Therapeutic Viewpoint

The glycosides of two flavonoids, naringin and naringenin, are found in various citrus fruits, bergamots, tomatoes, and other fruits. These phytochemicals are associated with multiple biological functions, including neuroprotective, antioxidant, anticancer, antiviral, antibacterial, anti-inflammatory, antiadipogenic, and cardioprotective effects. The higher glutathione/oxidized glutathione ratio in 3-NP-induced rats is attributed to the ability of naringin to reduce hydroxyl radical, hydroperoxide, and nitrite. However, although progress has been made in treating these diseases, there are still global concerns about how to obtain a solution. Thus, natural compounds can provide a promising strategy for treating many neurological conditions. Possible therapeutics for neurodegenerative disorders include naringin and naringenin polyphenols. New experimental evidence shows that these polyphenols exert a wide range of pharmacological activity; particular attention was paid to neurodegenerative diseases such as Alzheimer's and Parkinson's diseases, as well as other neurological conditions such as anxiety, depression, schizophrenia, and chronic hyperglycemic peripheral neuropathy. Several preliminary investigations have shown promising evidence of neuroprotection. The main objective of this review was to reflect on developments in understanding the molecular mechanisms underlying the development of naringin and naringenin as potential neuroprotective medications. Furthermore, the configuration relationships between naringin and naringenin are discussed, as well as their plant sources and extraction methods.

Naringin Attenuates the Diabetic Neuropathy in STZ-Induced Type 2 Diabetic Wistar Rats

The application of traditional medicines for the treatment of diseases, including diabetic neuropathy (DN), has received great attention. The aim of this study was to investigate the ameliorative potential of naringin, a flavanone, to treat streptozotocin-induced DN in rat models. After the successful induction of diabetes, DN complications were measured by various behavioral tests after 4 weeks of post-induction of diabetes with or without treatment with naringin. Serum biochemical assays such as fasting blood glucose, HbA1c%, insulin, lipid profile, and oxidative stress parameters were determined. Proinflammatory cytokines such as TNF-α and IL-6, and neuron-specific markers such as BDNF and NGF, were also assessed. In addition, pancreatic and brain tissues were subjected to histopathology to analyze structural alterations. The diabetic rats exhibited increased paw withdrawal frequencies for the acetone drop test and decreased frequencies for the plantar test, hot plate test, and tail flick test. The diabetic rats also showed an altered level of proinflammatory cytokines and oxidative stress parameters, as well as altered levels of proinflammatory cytokines and oxidative stress parameters. Naringin treatment significantly improved these parameters and helped in restoring the normal architecture of the brain and pancreatic tissues. The findings show that naringin's neuroprotective properties may be linked to its ability to suppress the overactivation of inflammatory molecules and mediators of oxidative stress.

Roasted cashew (Anacardium occidentale L.) nut-enhanced diet forestalls cisplatin-initiated brain harm in rats

The incessant dose constraining symptom of the chemotherapeutic agent, cisplatin is neurotoxicity. This examination tried to explore the neuroprotective impact of roasted cashew nut-enhanced diet against brain deficits related with treatment with cisplatin. Rats were separated in to six groups: Control, CIS (cisplatin [7 mg/kg body weight, i.p]), CIS +10% CN (cisplatin plus 10% roasted cashew nut), CIS +20% CN (cisplatin plus 20% roasted cashew nut), 10% CN (10% roasted cashew nut) and 20% CN (20% roasted cashew nut) for 28 days. Key enzymes associated with brain function, including cholinesterases (AChE and BChE), monoaminergic enzyme (MAO), arginase, and adenosine deaminase (ADA), were investigated after the treatment. The following oxidative stress indicators were also measured in the rat brain: glutathione-S-transferase (GST), glutathione peroxidase (GPx), total antioxidant capacity (TAC), total thiol (T-SH), non-protein thiol (NPSH), thiobarbituric acid reactive substances (TBARS), reactive oxygen species (ROS), nitric oxide (NO), superoxide dismutase (SOD). Our outcomes demonstrated that roasted cashew nut enhanced diet showed inhibitory impact on activities of AChE, BChE, ADA, MAO and arginase in cisplatin-induced rats. The roasted cashew nut supplemented diet also boosted redox equilibrium and displayed protection against cispaltin-induced oxidative damage to rats' brains by an increase in SOD, CAT, GST and GPx activities, TAC, T-SH, NPSH and NO levels as well as a considerable drop in ROS and RBARS levels. Roasted cashew nut enhanced diet additionally forestalled neuronal degeneration in rat brain. Thus, roasted cashew nuts could be used as a nutraceutical or functional food to treat cisplatin-induced neurotoxicity.

Practical applications

The results show that increasing roasted cashew nut consumption can significantly improve antioxidant status, reduce lipid peroxidation, and suppress cholinesterase, adenosine deaminase, monoamine oxidase, and arginase activities in the brain under cisplatin-induced circumstances.

Impact of ginseng on neurotoxicity induced by cisplatin in rats

Over the years, many researches have shown the potential protective effects of ginseng for preventing and treating neurological damage and their related diseases. Neuronal disturbance is one of the most common serious effects of cisplatin chemotherapy that triggers memory impairment and cognitive disability. Based on the hypothesis that mechanistic pathways of ginseng against the neurological and biochemical disturbance remain unclear, therefore, this study was designed to investigate the neuroprotective effect of ginseng extract against neurological and behavior abnormality induced by cisplatin in male rats. Animals were divided into 4 groups. Group 1 served as a control, group 2 was orally administrated with ginseng (100 mg/kg BW) daily for 90 days, group 3 was injected intraperitoneally with cisplatin (4 mg/kg BW) once a week for 90 days, and group 4 received ginseng and cisplatin. Cisplatin induced a learning and memory dysfunction in the Morris water maze task and locomotor disability in the rotarod test. In addition, cisplatin disrupted the oxidant/antioxidant systems, neuroinflammatory molecules (TNF-α, IL-6, IL-12, and IL-1β), neurotransmitters, and apoptotic (caspase-3, P53, and Bax) and dementia markers (amyloid-β40 and amyloid-β 42). Co-treatment with ginseng extracts successfully ameliorated the cognitive behaviors and intramuscular strength and presented a good protective agent against neurological damage. Histopathological and histochemical studies proved the neuroprotective effect of ginseng. Our data showed that ginseng capable to counteract the memory dysfunction is induced by cisplatin via reducing oxidative stress and neuroinflammation restoring the neurological efficiency.

Naringenin Attenuates Cognitive Impairment in a Rat Model of Vascular Dementia by Inhibiting Hippocampal Oxidative Stress and Inflammatory Response and Promoting N-Methyl-D-Aspartate Receptor Signaling Pathway

Vascular dementia (VaD) is the second most common form of dementia globally, yet there are no efficient treatments. Naringenin, a natural flavonoid, exerts antioxidative, anti-inflammatory, and neuroprotective properties; however, its potential effect on VaD remain unclear. Herein, the purpose of present study was to elucidate whether naringenin attenuates cognitive dysfunction in VaD via inhibiting hippocampal oxidative stress and inflammatory response, and promoting N-methyl-D-aspartate receptors (NMDARs) signaling pathway. A rat model of VaD was established by permanent bilateral common carotid artery occlusion [2-vessel occlusion (2VO)]. Behavioral performance analyses results revealed that administration of naringenin improves cognitive impairment in rats with VaD according to the new object recognition test and the Morris water maze test. In addition, naringenin attenuated hippocampal oxidative stress by reducing reactive oxygen species generation, decreasing malondialdehyde content and recombinant reactive oxygen species modulator 1 (Romo-1) expression, and increasing superoxide dismutase and glutathione peroxidase activities in the hippocampus of VaD rats. Moreover, naringenin decreased the proinflammatory cytokines (IL-1β, IL-6, and TNF-α) levels and increased the anti-inflammatory cytokines (IL-10 and IL-4) levels in the hippocampus of 2VO surgery-treated rats, attenuating hippocampal inflammatory response during VaD. Furthermore, naringenin promoted synaptophysin (SYP), postsynaptic density protein 95 (PSD95), N-methyl-Daspartic acid receptor 1 (NR1) and N-methyl-D-aspartate receptor subunit 2B (NR2B) expressions levels in hippocampus of VaD rats. Collectively, these findings indicated that naringenin mitigates cognitive impairment in VaD rats partly via inhibiting hippocampal oxidative stress and inflammatory response and restoring NMDARs signaling pathway.

Artichoke Leaf Extract-Mediated Neuroprotection against Effects of Aflatoxin in Male Rats

Attenuation of adverse effects of aflatoxin (AFB₁) in brains of B₁ rats by extracts of leaves of artichoke was studied. The active ingredients in extracts of leaves of artichoke, Cynara scolymus L., were determined by HPLC analysis. In the 42-day experiment, rats were exposed to either sterile water, 4% DMSO, 100 mg artichoke leaf extract/kg body mass, 72 μg aflatoxin B₁/kg body mass, or AFB₁ plus artichoke leaf extract. Neurotoxicity of AFB₁ was determined by an increase in profile of lipids, augmentation of plasmatic glucose and concentrations of insulin, oxidative stress, increased activities of cholinergic enzymes, and a decrease in activities of several antioxidant enzymes and pathological changes in brain tissue. Extracts of artichoke leaf significantly reduced adverse effects caused by AFB₁, rescuing most of the parameters to values similar to unexposed controls, which demonstrated that adverse, neurotoxic effects caused by aflatoxin B₁ could be significantly reduced by simultaneous dietary supplementation with artichoke leaf extract, which itself is not toxic.

Chemobrain in Breast Cancer: Mechanisms, Clinical Manifestations, and Potential Interventions

Among the potential adverse effects of breast cancer treatment, chemotherapy-related cognitive impairment (CRCI) has gained increased attention in the past years. In this review, we provide an overview of the literature regarding CRCI in breast cancer, focusing on three main aspects. The first aspect relates to the molecular mechanisms linking individual drugs commonly used to treat breast cancer and CRCI, which include oxidative stress and inflammation, reduced neurogenesis, reduced levels of specific neurotransmitters, alterations in neuronal dendrites and spines, and impairment in myelin production. The second aspect is related to the clinical characteristics of CRCI in patients with breast cancer treated with different drug combinations. Data suggest the incidence rates of CRCI in breast cancer vary considerably, and may affect more than 50% of treated patients. Both chemotherapy regimens with or without anthracyclines have been associated with CRCI manifestations. While cross-sectional studies suggest the presence of symptoms up to 20 years after treatment, longitudinal studies confirm cognitive impairments lasting for at most 4 years after the end of chemotherapy. The third and final aspect is related to possible therapeutic interventions. Although there is still no standard of care to treat CRCI, several pharmacological and non-pharmacological approaches have shown interesting results. In summary, even if cognitive impairments derived from chemotherapy resolve with time, awareness of CRCI is crucial to provide patients with a better understanding of the syndrome and to offer them the best care directed at improving quality of life.

Melatonin is effective in attenuating cisplatin-induced neurotoxicity

Cisplatin (Cis) is a chemotherapeutic agent that has many side effects. Neurotoxicity is one of the most important of these side effects. Oxidative stress and neuroinflammation are the best-known mechanisms in the pathogenesis of neurotoxicity development. In this study, we aimed to determine whether melatonin (Mel), with antioxidant and anti-inflammatory effects, is effective in preventing Cis-induced neurotoxicity. Forty-eight male Sprague-Dawley rats were divided into six groups (n = 8) as follows: control (0.9% NaCl), vehicle (5% ethanol), Cis (6 mg/kg), Cis (6 mg/kg) + vehicle (5% ethanol), Mel (20 mg/kg), and Cis (6 mg/kg) + Mel (20 mg/kg) groups. Cis was administered as a single dose on the 3rd day of the experiment while Mel was given for 5 days. All administrations were performed via intraperitoneal injection. After injections, T-maze, rotarod, and hot plate tests were performed to evaluate cognitive, motor, and sensory functions, respectively. Following sacrification oxidative stress markers, cholinergic function, and proinflammatory cytokines were studied from brain homogenates. Cis impaired cognitive function and motor performance in the Cis and Cis+Vehicle groups. The drug also increased oxidative stress in the brain. Mel significantly improved brain oxidant/antioxidant status and also decreased the overproduction of proinflammatory cytokines (superoxide dismutase activities in Cis+Vehicle and Cis+Mel groups: 104.55 ± 9.50 µU/mg protein vs. 150.13 ± 4.70 µU/mg protein, respectively, p < 0.05; tumor necrosis factor-α levels in Cis and Cis+Mel groups: 40 pg/ml vs. 20 pg/ml, respectively, p < 0.05). It seems that Mel can improve Cis neurotoxicity. For a more firm conclusion, further studies using Mel at different doses with larger groups should be performed.

The Inhibitory Effects of Naringin in a Rat Model of Postoperative Intraperitoneal Adhesion Formation

Background

Many attempts have been made to inhibit the formation of postoperative intraperitoneal adhesions, but the results have been discouraging. Therefore, the identification of effective preventative measures or treatments is of great importance. In this study, the substantial potential of naringin (NG) to reduce peritoneal adhesions was validated in a rat model.

Materials and Methods

A rat peritoneal adhesion model was established by abrasion of the cecum and its opposite intraperitoneal region under aseptic surgical conditions. After the operation, three groups of NG-treated rats were given 2 mL of NG by gavage at different concentrations (40, 60, or 80 mg/kg/d). The sham, control, and hyaluronan (HA) groups were given equal volumes of normal saline daily. On the 8th day, all rats were sacrificed 30 min after the administration of an activated carbon solution (10 mL/kg) by oral gavage. Intraperitoneal adhesion formation was adequately evaluated by necropsy, hematoxylin and eosin (HE) staining, Sirius red staining, immunofluorescence staining, enzyme-linked immunosorbent assays, and reactive oxygen species (ROS) probes. The gastrointestinal dynamics of the rats were assessed on the basis of a small intestinal charcoal powder propulsion test and the detection of motilin and gastrin levels in serum.

Results

Intraperitoneal adhesions were markedly reduced in the group of rats receiving high-dose NG. Compared with the control group, the high-dose NG group showed clear reductions in inflammatory reactions, oxidative stress, collagen deposition, and fibroblast formation in the adhesion tissue and enhanced gastrointestinal dynamics (P < 0.05).

Conclusion

NG alleviated the severity of intraperitoneal adhesions in a rat model by reducing inflammation, oxidative stress, collagen deposition, and fibroblast formation, highlighting the potential of NG as a drug candidate to prevent postoperative peritoneal adhesion formation.

Antioxidant and Anti-inflammatory Properties Mediate the Neuroprotective Effects of Hydro-ethanolic Extract of Tiliacora triandra Against Cisplatin-induced Neurotoxicity

Background

Cisplatin (CDDP) is an efficacious anticancer agent used widely in chemotherapy despite its severe side effect related to neurotoxicity. Redox imbalance and inflammatory mechanism have been implicated in the pathophysiology of CDDP-induced neurotoxicity. Herein, we investigated whether Tiliacora triandra (TT) extract could inhibit  CDDP-induced redox-mediated neurotoxicity and behavioural deficit in rats.

Materials and Methods

CDDP-induced redox-mediated neurotoxicity and behavioral deficit in rats. Rats were administered TT for five consecutive weeks (250 and 500 mg/kg bw), while weekly i.p. injection of CDDP commenced on the second week (2.5 mg/kg bw) of the TT administration.

Results

CCDDP caused significant body weight reduction and cognitive diminution as revealed by Morris water maze and Y maze tests. In the CDDP-induced cognitive impairment (CICI) rats, there were remarkable increases in the brain levels of TNF-α, IL-6 and IL-1β and malondialdehyde (MDA), whereas catalase (CAT), glutathione (GSH), glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities considerably decreased compared to normal control. The brain acetylcholinesterase (AChE) activity in CDDP control rats was significantly increased compared to the normal control. The expression of caspase-3 and p53 proteins was upregulated by CDDP injection, whereas Bcl2 was downregulated coupled with histopathological alterations in the rat brain. Interestingly, treatment with TT significantly abated neurobehavioral deficits, MDA and cytokine levels and restored CAT, GPx, GSH, SOD, and AChE activities compared to the CDDP control rats. Caspase-3 level as well as Bcl2 and p53 expressions were modulated with alleviated changes in histopathology.

Conclusion

The findings highlight neuroprotective and cognitive function improvement efficacy of TT against CICI via redox-inflammatory balance and antiapoptotic mechanism in rats.

Dietary agents in mitigating chemotherapy-related cognitive impairment (chemobrain or chemofog): first review addressing the benefits, gaps, challenges and ways forward

Chemobrain or chemofog is one of the important but less investigated side effects, where the cancer survivors treated with chemotherapy develop long-term cognitive impairments, affecting their quality of life. The biological mechanisms triggering the development of chemobrain are largely unknown. However, a literature study suggests the generation of free radicals, oxidative stress, inflammatory cytokines, epigenetic chromatin remodeling, decreased neurogenesis, secretion of brain-derived neurotropic factor (BDNF), dendritic branching, and neurotransmitter release to be the cumulative contributions to the ailment. Unfortunately, there is no means to prevent/mitigate the development and intensity of chemobrain. Given the lack of effective prevention strategies or treatments, preclinical studies have been underway to ascertain the usefulness of natural products in mitigating chemobrain in the recent past. Natural products used in diets have been shown to provide beneficial effects by inhibition of free radicals, oxidative stress, inflammatory processes, and/or concomitant upregulation of various cell survival proteins. For the first time, this review focuses on the published effects of astaxanthin, omega-3 fatty acids, ginsenoside, cotinine, resveratrol, polydatin, catechin, rutin, naringin, curcumin, dehydrozingerone, berberine, C-phycocyanin, the higher fungi Cordyceps militaris, thyme (Thymus vulgaris) and polyherbal formulation Mulmina™ in mitigating cognitive impairments in preclinical models of study, and also addresses their potential neuro-therapeutic mechanisms and applications in preventing/ameliorating chemobrain.

Naringin as Sustained Delivery Nanoparticles Ameliorates the Anti-inflammatory Activity in a Freund's Complete Adjuvant-Induced Arthritis Model

Naringin (NAR), a naturally occurring essential flavonoid, present in grapefruit and Chinese herbal medicines, creates great interest in researchers due to its diverse biological and pharmacological activities. However, further development of NAR is hindered due to its poor water solubility and dissolution rates in GIT. To address these limitations, in this study, we report polymeric nanoparticles (NPs) of NAR (NAR-PLGA-NPs) for enhancing the oral NAR efficiency, with a biodegradable polymer (PLGA) to improve its absorption and bioavailability. NAR-PLGA-NPs were fabricated by a modified solvent emulsification-evaporation technique. Physicochemical properties were evaluated by SEM, particle size distribution, entrapment efficiency, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). In vitro drug release and ex vivo permeation studies were carried out in phosphate buffer (pH 6.8) for 24 h. Furthermore, in vivo anti-arthritic studies were performed on a mouse model, and the results were compared with free NAR. The modulation of inflammatory mediators was also evidently supported by docking studies. Optimized nanoformulation FN4 (NAR-PLGA-NPs) prepared with acetone-ethanol (2:1) as a solvent system in a combination of stabilizers, i.e., poloxamer-188 and sodium deoxylate (1:1), along with 2% PVA solution, was prepared. From size characterization studies, it was observed that nanoformulations possessed a low particle size (179.7 ± 2.05 nm), a low polydispersity index (0.206 ± 0.001), and a negative zeta potential (-9.18 ± 0.78 mV) with a maximum entrapment efficiency (74 ± 3.61%). The drug release followed a Korsmeyer-Peppas release kinetic model (anomalous non-Fickian diffusion), providing greater NAR release after lyophilization (82.11 ± 3.65%) drug release in pH 6.8 phosphate buffer for 24 h. Ex vivo permeation analysis through an isolated goat intestinal membrane revealed 80.02 ± 3.69% drug release in 24 h. Encapsulation of a drug into PLGA is well described by the results of FTIR, DSC, and XRD. Finally, the therapeutic efficacy of optimized FN4 (NAR-PLGA-NPs) and its possible application on RA were further confirmed in a Freund's complete adjuvant-induced rat arthritic model as against free NAR at a dose of 20 mg/kg body wt. Our findings demonstrate that sustained action of NAR from optimized FN4 NPs with a rate-controlling polymeric carrier system exhibited prolonged circulation time and reduced arthritic inflammation, hence indicating the possibility as a novel strategy to secure the unpropitious biological interactions of hydrophobic NAR in a gastric environment.

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.

Flavonoids in the Treatment of Neuropathic Pain

PURPOSE OF REVIEW

Chronic pain continues to present a large burden to the US healthcare system. Neuropathic pain, a common class of chronic pain, remains particularly difficult to treat despite extensive research efforts. Current pharmacologic regimens exert limited efficacy and wide, potentially dangerous side effect profiles. This review provides a comprehensive, preclinical evaluation of the literature regarding the role of flavonoids in the treatment of neuropathic pain.

RECENT FINDINGS

Flavonoids are naturally occurring compounds, found in plants and various dietary sources, which may have potential benefit in neuropathic pain. Numerous animal-model studies have demonstrated this benefit, including reversal of hyperalgesia and allodynia. Flavonoids have also exhibited an anti-inflammatory effect relevant to neuropathic pain, as evidenced by the reduction in multiple pro-inflammatory mediators, such as TNF-α, NF-κB, IL-1β, and IL-6. Flavonoids represent a potentially new treatment modality for neuropathic pain in preclinical models, though human clinical evidence is yet to be explored at this time.

Naringin Supplementation during Pregnancy Induces Sex and Region-Specific Alterations in the Offspring's Brain Redox Status

Research has shown the beneficial effects of naringin supplementation to adult rodents, which can ameliorate oxidative stress in disease models. However, evidence has demonstrated that polyphenol supplementation induced detrimental effects when consumed during sensitive periods of development, such as pregnancy. Therefore, we investigated the effect of maternal naringin supplementation during pregnancy on the offspring’s cerebral redox status. Pregnant Wistar rats were divided into control and naringin groups and supplemented from gestational day 15 to gestational day 21. On postnatal days 1, 7, and 21, offspring were euthanized, and the prefrontal cortex, hippocampus, striatum, and cerebellum dissected. On postnatal day 1, maternal naringin supplementation positively modulated the pups’ brain redox status. On postnatal day 7, a pro-oxidative milieu was observed in the offspring’s striatum and cerebellum in a sex-dependent manner, even though the prefrontal cortex and hippocampus were not negatively affected. Besides, the alterations observed on postnatal day 7 did not persist up to weaning. Our findings demonstrated that the effect induced by naringin supplementation in the brain redox status differed according to the period of development in which naringin was consumed since the beneficial effects usually found in the adult rodents became detrimental when the supplementation was applied during pregnancy.

Flavonoids Alleviate Peripheral Neuropathy Induced by Anticancer Drugs

Simple Summary

Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating condition that severely reduces the quality of life of a considerable proportion of cancer patients. There is no cure for CIPN to date. Here, we explore the potential of flavonoids as pharmacological agents in combating CIPN. Flavonoids alleviate CIPN by reducing oxidative stress, inflammation, and neuronal damage, among other mechanisms. Future research should evaluate the efficacy and side effects of flavonoids in human models of CIPN.

Abstract

Purpose: This study aimed to assess the potential of flavonoids in combating CIPN. Methods: PubMed and Google Scholar were used, and studies that investigated flavonoids in models of CIPN and models of neuropathic pain similar to CIPN were included. Only studies investigating peripheral mechanisms of CIPN were used. Results: Flavonoids inhibit several essential mechanisms of CIPN, such as proinflammatory cytokine release, astrocyte and microglial activation, oxidative stress, neuronal damage and apoptosis, mitochondrial damage, ectopic discharge, and ion channel activation. They decreased the severity of certain CIPN symptoms, such as thermal hyperalgesia and mechanical, tactile, and cold allodynia. Conclusions: Flavonoids hold immense promise in treating CIPN; thus, future research should investigate their effects in humans. Specifically, precise pharmacological mechanisms and side effects need to be elucidated in human models before clinical benefits can be achieved.

Citrus Polyphenols in Brain Health and Disease: Current Perspectives

In addition to essential micronutrients such as vitamin C, citrus fruits represent a considerably rich source of non-essential bioactive compounds, in particular flavanones which form a sub-set of the flavonoid group. Preclinical studies have demonstrated the neuroprotective potential of citrus flavonoids and have highlighted both the well-established (anti-inflammatory and anti-oxidative properties), and newly emerging (influence upon blood-brain barrier function/integrity) mechanistic actions by which these neurological effects are mediated. Encouragingly, results from human studies, although limited in number, appear to support this preclinical basis, with improvements in cognitive performance and disease risk observed across healthy and disease states. Therefore, citrus fruits - both as whole fruit and 100% juices - should be encouraged within the diet for their potential neurological benefit. In addition, there should be further exploration of citrus polyphenols to establish therapeutic efficacy, particularly in the context of well-designed human interventions.

Naringin Exhibits Mas Receptor-Mediated Neuroprotection Against Amyloid Beta-Induced Cognitive Deficits and Mitochondrial Toxicity in Rat Brain

Alzheimer's disease (AD) is a progressive neurodegenerative disorder with clinical manifestation of loss in cognitive functions in an individual. Though several drug candidates have been developed in the management of AD, an alternative option is still required due to serious adverse effects of the former. Recently, naringin exerts therapeutic benefits through rennin angiotensin system in experimental animals. However, its report  on Mas receptor-mediated action against amyloid beta (Aβ)-induced mitochondrial dysfunction in AD-like animals is lacking. The experimental dementia was induced in the male rats by intracerebroventricular administration of Aβ_(1-42) on day 1 (D-1) of the experimental schedule of 14 days. Naringin treatment for 14 days attenuated Aβ-induced cognitive impairments of the animals in Morris water maze (MWM) and Y-maze tests. Further, naringin ameliorated the Aβ-induced cholinergic dysfunction in terms of decrease in the activity of choline acetyl transferase (ChAT) and level of acetylcholine (ACh) and increase in the activity of acetylcholine esterase (AChE) in rat hippocampus, prefrontal cortex, and amygdala. Furthermore, naringin attenuated Aβ-induced decrease in mitochondrial function, integrity, and bioenergetics in all the brain regions. Naringin also attenuated Aβ-induced increase in mitochondrial and cytosolic calcium level in all the brain regions. Moreover, naringin reversed Aβ-induced increase in apoptosis and level of mitochondrial calcium uniporter and decrease in the level of hemeoxygenase-1 in all the brain regions. On the contrary, A779 significantly abolished the therapeutic potential of naringin on Aβ-induced alteration in behavioral, biochemical, and molecular observations in these experimental animals. Thus, these observations indicate that naringin could be potential alternative in the management of AD.

Animal models of chemotherapy-induced cognitive decline in preclinical drug development

RATIONALE

Chemotherapy-induced cognitive impairment (CICI), chemobrain, and chemofog are the common terms for mental dysfunction in a cancer patient/survivor under the influence of chemotherapeutics. CICI is manifested as short/long term memory problems and delayed mental processing, which interferes with a person's day-to-day activities. Understanding CICI mechanisms help in developing therapeutic interventions that may alleviate the disease condition. Animal models facilitate critical evaluation to elucidate the underlying mechanisms and form an integral part of verifying different treatment hypotheses and strategies.

OBJECTIVES

A methodical evaluation of scientific literature is required to understand cognitive changes associated with the use of chemotherapeutic agents in different preclinical studies. This review mainly emphasizes animal models developed with various chemotherapeutic agents individually and in combination, with their proposed mechanisms contributing to the cognitive dysfunction. This review also points toward the analysis of chemobrain in healthy animals to understand the mechanism of interventions in absence of tumor and in tumor-bearing animals to mimic human cancer conditions to screen potential drug candidates against chemobrain.

RESULTS

Substantial memory deficit as a result of commonly used chemotherapeutic agents was evidenced in healthy and tumor-bearing animals. Spatial and episodic cognitive impairments, alterations in neurotrophins, oxidative and inflammatory markers, and changes in long-term potentiation were commonly observed changes in different animal models irrespective of the chemotherapeutic agent.

CONCLUSION

Dyscognition exists as one of the serious side effects of cancer chemotherapy. Due to differing mechanisms of chemotherapeutic agents with differing tendencies to alter behavioral and biochemical parameters, chemotherapy may present a significant risk in resulting memory impairments in healthy as well as tumor-bearing animals.

Exploring the Promise of Flavonoids to Combat Neuropathic Pain: From Molecular Mechanisms to Therapeutic Implications

Neuropathic pain (NP) is the result of irregular processing in the central or peripheral nervous system, which is generally caused by neuronal injury. The management of NP represents a great challenge owing to its heterogeneous profile and the significant undesirable side effects of the frequently prescribed psychoactive agents, including benzodiazepines (BDZ). Currently, several established drugs including antidepressants, anticonvulsants, topical lidocaine, and opioids are used to treat NP, but they exert a wide range of adverse effects. To reduce the burden of adverse effects, we need to investigate alternative therapeutics for the management of NP. Flavonoids are the most common secondary metabolites of plants used in folkloric medicine as tranquilizers, and have been claimed to have a selective affinity to the BDZ binding site. Several studies in animal models have reported that flavonoids can reduce NP. In this paper, we emphasize the potentiality of flavonoids for the management of NP.

Potential Protective Effects of Naringin on Oculo-Pulmonary Injury Induced by PM10 (Wood Smoke) Exposure by Modulation of Oxidative Damage and Acetylcholine Esterase Activity in a Rat Model

BACKGROUND

Millions of households in the world depend on wood and biomass for cooking and heating. This dependence leads to undesirable toxic effects, such as ocular and pulmonary toxicity.

OBJECTIVES

The present study examined the potential oculoprotective and pulmonary protective activity of naringin (NRG), a naturally occurring flavonoid, against wood smoke (WS)-induced toxicity in a rat model.

METHODS

Forty-eight adult male albino rats were randomly distributed into six (n=8) groups. All rats were fed, given water, and observed for 21 days, Group I (control) received only distilled water and no WS exposure, Group II was exposed to WS, Group III was exposed to WS and given 50 mg/kg/d α-tocopherol (vitamin E), Group IV was exposed to WS and given 80 mg/kg/day NRG, Group V was administered only 80 mg/kg/d NRG only, and Group VI was administered only 50 mg/kg/d vitamin E. WS exposure was for 20 min/d. The effect of NRG treatment on acetylcholinesterase activity, nitric oxide radical production, malondialdehyde level, and antioxidant enzymes (ie, superoxide dismustase and catalase) in WS-exposed rats was examined.

RESULTS

Subchronic (21 day) exposure to WS induced ocular and pulmonary toxicity manifested by the infiltration of parenchyma, atrophy, and inflammation of the cells, which was correlated with alterations in antioxidant enzyme concentrations. Cell damage was associated with an increase in acetylcholinesterase activity and nitric oxide radical concentrations. The toxicity triggered by WS was modulated by the coadministration of NRG.

CONCLUSION

These results suggest that NRG treatment may be useful to reduce WS-induced oxidative stress and related ocular and pulmonary damage in rats. (Curr Ther Res Clin Exp. 2012; 73:XXX-XXX).

In Vitro and In Vivo Effects of Flavonoids on Peripheral Neuropathic Pain

Neuropathic pain is a common symptom and is associated with an impaired quality of life. It is caused by the lesion or disease of the somatosensory system. Neuropathic pain syndromes can be subdivided into two categories: central and peripheral neuropathic pain. The present review highlights the peripheral neuropathic models, including spared nerve injury, spinal nerve ligation, partial sciatic nerve injury, diabetes-induced neuropathy, chemotherapy-induced neuropathy, chronic constriction injury, and related conditions. The drugs which are currently used to attenuate peripheral neuropathy, such as antidepressants, anticonvulsants, baclofen, and clonidine, are associated with adverse side effects. These negative side effects necessitate the investigation of alternative therapeutics for treating neuropathic pain conditions. Flavonoids have been reported to alleviate neuropathic pain in murine models. The present review elucidates that several flavonoids attenuate different peripheral neuropathic pain conditions at behavioral, electrophysiological, biochemical and molecular biological levels in different murine models. Therefore, the flavonoids hold future promise and can be effectively used in treating or mitigating peripheral neuropathic conditions. Thus, future studies should focus on the structure-activity relationships among different categories of flavonoids and develop therapeutic products that enhance their antineuropathic effects.

Effect of memantine hydrochloride on cisplatin-induced neurobehavioral toxicity in mice

Cisplatin is an anticancer agent widely used in the treatment of malignant tumors. One of the major adverse effects of cisplatin is its neurotoxicity. Memantine, an uncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist, has been reported to have neuroprotective effects against neurological deficits. This study therefore investigated the possible protective role of memantine as an agent to minimize the neurobehavioral toxic side effects of cisplatin. Two different therapeutic doses of memantine (5 mg/kg) and (10 mg/kg) were orally administered for 30 days to 50 male BALB/c mice divided into 5 groups: G1: no treatment; G2: cisplatin treatment; G3: memantine treatment; G4: pretreatment of (5 mg/kg) memantine with cisplatin (4 mg/kg); G5: pretreatment of 10 mg/kg memantine with cisplatin (4 mg/kg). Weekly neurobehavioral investigations were conducted using the following battery of tests: open field activity, negative geotaxis, hole-board test, swimming test, and calculation of weight. At the end of the experimental period the mice were euthanized, and immunohistochemistry was then used to measure the expression scores of nicotinic acetylcholine receptors (nAChRs) in the muscles and brain. Results revealed that mice in G2 showed a significant decrease in the ability to perform neurobehavioral tasks. The mice in G5 exhibited a significantly improved ability on these tests, indicating a complete neurobehavioral protective effect, while the mice in G4 showed partial protection. The nAChRs score showed higher expression in the case of G2 in comparison with G3, G4, and G5. Weight loss was exhibited in G2, while in G3 and G1 these values were normal. A therapeutic dose of memantine 10 mg/kg yielded more protection than 5 mg/kg in the treatment of neuropathy; this highlights the importance of using memantine to decrease the main side effects of cisplatin.

Overview of cisplatin-induced neurotoxicity and ototoxicity, and the protective agents

Cisplatin has dramatically improved the survival rate of cancer patients, but it has also increased the prevalence of hearing and neurological deficits in this population. Cisplatin induces ototoxicity, peripheral (most prevalent) and central (rare) neurotoxicity. This review addresses the ototoxicity and the neurotoxicity associated with cisplatin-based chemotherapy, providing an integrated view of the potential protective agents that have been evaluated in vitro, in vivo and in clinical trials, their targets and mechanisms of protection and their effects on the antitumor activity of cisplatin. So far, the findings are insufficient to support the use of any oto- or neuroprotective agent before, during or after cisplatin chemotherapy. Despite their promising effects in vitro and in animal studies, many agents have not been evaluated in clinical trials. Additionally, the clinical trials have limitations concerning the sample size, controls, measurement, heterogeneous groups, several arms of treatment, short follow-up or no blinding. Besides that, for most agents, the effects on the antitumor activity of cisplatin have not been evaluated in tumor-bearing animals, which discourages clinical trials. Further well-designed randomized controlled clinical trials are necessary to definitely demonstrate the effectiveness of the oto- or neuroprotective agents proposed by animal and in vitro studies.

Doxorubicin and cisplatin induced cognitive impairment: The possible mechanisms and interventions

Chemotherapy has significantly increased the number of cancer survivors. However, chemotherapy itself carries various adverse effects that limit the efficacy of treatment and quality of life of the cancer patients. Most patients who have received chemotherapy report some cognitive deficit characterized by dysfunction in memory, learning, concentration, and reasoning. The phenomenon of cognitive decline developed from chemotherapy treatment is referred to as chemotherapy-induced cognitive impairment (CICI) or chemobrain. The two most common cancers occurring worldwide are lung and breast cancer. The predominant chemotherapeutic drugs used to treat lung and breast cancer are doxorubicin and cisplatin. There is evidence to suggest that both drugs potentially induce chemobrain. The evidence around the proposed pathogenesis of chemobrain caused by these two drugs is inconsistent. Understanding the underlying mechanisms involved in the development of chemobrain would aid in the prevention or treatment of the adverse effects of chemotherapy on brain. This review will summarize and discuss controversial findings and possible mechanisms involved in the development of chemobrain and the interventions which could limit it from in vitro, in vivo, and clinical studies.

Protective Role of Epigallocatechin Gallate in a Rat Model of Cisplatin-Induced Cerebral Inflammation and Oxidative Damage: Impact of Modulating NF-κB and Nrf2

Cisplatin is a widely used chemotherapeutic agent in treating various types of cancers. However, it can induce neurotoxicity and nephrotoxicity, limiting its dose and clinical use. Although previous studies indicated the direct link between cisplatin-induced central neurotoxicity and oxidative stress, the exact mechanism is not completely understood. Therefore, herein we investigated the effects of prophylactic and concurrent treatment with (-)-epigallocatechin-3-gallate (EGCG), a natural polyphenolic neuroprotective antioxidant, on cisplatin-induced brain toxicity in rats to delineate its molecular mechanism of action. We found that cisplatin initiated a cascade of genetic, biological, and histopathological changes in the brain cortex, inducing inflammatory cytokines, appearance of scattered inflammatory cells, nitro-oxidative stress, and apoptotic proteins in the cerebral cortex. However, EGCG not only protected against cisplatin-induced inflammatory burden but also ameliorated the induction of nitro-oxidative stress and apoptotic proteins triggered by cisplatin in the cerebral cortex of pre- and co-treated rats with respect to their unprotected counterparts. EGCG anti-inflammatory effect here may be attributed to the downregulation of nuclear factor kappa B (NF-κB). Additionally, this natural polyphenol significantly ameliorated cisplatin-elicited reduction in cerebral cortex brain-derived neurotrophic factor and acetylcholine esterase. Upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream heme oxygenase-1 (HO-1) by EGCG prophylactic and concurrent administration here seems also to play a key role in the protective impact of EGCG against cisplatin toxicity through enhancing total antioxidant capacity. Thus, EGCG can be used as a promising prophylactic adjuvant for preventing the development of brain inflammation and oxidative damage associated with cisplatin chemotherapy.

Neuroprotective effect of N-acetylcysteine against cisplatin-induced toxicity in rat brain by modulation of oxidative stress and inflammation

BACKGROUND

Neurotoxicity is a major obstacle to the effectiveness of cisplatin (CDDP) in cancer chemotherapy. Oxidative stress and inflammation are considered to be the major mechanisms involved in CDDP-induced neurotoxicity. The rationale of our study was to investigate the efficacy of N-acetylcysteine (NAC) at two different doses in the management of CDDP-induced toxicity in rat brain by monitoring its antioxidant and anti-inflammatory effects.

METHODS

Thirty-five male rats were divided into five groups (n=7) as follows: control group (0.5 mL saline), NAC100 group (100 mg/kg), CDDP group (8 mg/kg), NAC50-CDDP group (50 mg/kg NAC and 8 mg/kg CDDP), and NAC100-CDDP group (100 mg/kg NAC and 8 mg/kg CDDP). NAC was administered for 20 consecutive days, while CDDP was injected once on day 15 of the treatment protocol.

RESULTS

The neurotoxicity of CDDP was evidenced by a marked increase in acetylcholinesterase and monoamine oxidase activities. It also induced oxidative stress as indicated by increased levels of lipid peroxidation, nitric oxide, and protein carbonyl with a concomitant decline in reduced glutathione, glutathione peroxidase, glutathione S-transferase, superoxide dismutase, and catalase in the brain. Moreover, CDDP enhanced the synthesis of pro-inflammatory cytokines such as tumor necrosis factor-α, interleukin-1β, and interleukin-6. Treatment with NAC at the two selected doses significantly attenuated CDDP-induced changes in the brain cholinergic function, improved the brain oxidant/antioxidant status, and also reversed the overproduction of pro-inflammatory cytokines in brain and serum.

CONCLUSION

NAC could serve as an appropriate and safe complementary therapeutic agent to attenuate the toxicity of CDDP in the brain and therefore improve its outcomes in chemotherapy.

Possible neuroprotective mechanisms of action involved in the neurobehavioral property of naringin in mice

Flavonoids are naturally occurring bioactive phytochemical metabolites widely known to prevent and suppress several human diseases, and are important sources of therapeutic compounds from plants. Evidence derived from previous studies suggests that naringin, a neuroactive flavonoid possess functional beneficial neurobehavioral effects including anxiolytic, antidepressant and memory enhancing properties. However, literature search revealed that no studies have been carried out to evaluate the possible biochemical mechanisms involved in the neurobehavioral property of naringin alone following repeated treatment. Hence, this study was designed to evaluate the possible neuro-biochemical mechanisms involved in the neurobehavioral property of naringin following repeated administration in mice. The effects of naringin (2.5, 5 and 10 mg/kg), diazepam (2 mg/kg), imipramine (15 mg/kg) and donepezil (1 mg/kg) or vehicle on neurobehavioral and biochemical effects were evaluated in mice following repeated intraperitoneal injection for 7 consecutive days. Neurobehavioral activities consisting of open-field (locomotor), elevated-plus maze (anxiolytic), forced swim and social interaction (antidepressant and social preference), and Y-maze (memory enhancing) tests were assessed. Thereafter, brains levels of biomarkers of oxidative, nitrosative and cholinergic parameters were determined. Repeated treatment with naringin produced increased locomotor activity, and demonstrated antidepressant-like effects evidenced by decreased immobility time in forced swim test and increased % social preference in the social interaction test relative to controls. Also, naringin induced anxiolytic-like effect and increased cognitive performance in mice. Mechanistically, naringin significantly increased the activities of superoxide dismutase and catalase, and glutathione concentration relative to vehicle-controls. However, naringin significantly decreased malondialdehyde and nitrite contents, and reduced brain acetylcholinesterase activity in mice brains in a significant manner relative to controls. Taken together, these findings suggest that treatment with naringin might be useful to produce functional behavioral effects via mechanisms related to enhancement of cholinergic transmission, antioxidant defense systems, inhibition of lipid peroxidation and nitrosative processes.

C60 fullerene and its nanocomplexes with anticancer drugs modulate circulating phagocyte functions and dramatically increase ROS generation in transformed monocytes

Background

C₆₀ fullerene-based nanoformulations are proposed to have a direct toxic effect on tumor cells. Previous investigations demonstrated that C₆₀ fullerene used alone or being conjugated with chemotherapeutic agents possesses a potent anticancer activity. The main aim of this study was to investigate the effect of C₆₀ fullerene and its nanocomplexes with anticancer drugs on human phagocyte metabolic profile in vitro.

Methods

Analysis of the metabolic profile of phagocytes exposed to C₆₀ fullerene in vitro revealed augmented phagocytic activity and down-regulated reactive nitrogen species generation in these cells. Additionally, cytofluorimetric analysis showed that C₆₀ fullerene can exert direct cytotoxic effect on normal and transformed phagocytes through the vigorous induction of intracellular reactive oxygen species generation.

Results

Cytotoxic action as well as the pro-oxidant effect of C₆₀ fullerene was more pronounced toward malignant phagocytes. At the same time, C₆₀ fullerenes have the ability to down-regulate the pro-oxidant effect of cisplatin on normal cells. These results indicate that C₆₀ fullerenes may influence phagocyte metabolism and have both pro-oxidant and antioxidant properties.

Conclusions

The antineoplastic effect of C₆₀ fullerene has been observed by direct toxic effect on tumor cells, as well as through the modulation of the functions of effector cells of antitumor immunity.

Preparation, characterization and in vitro and in vivo evaluation of a solid dispersion of Naringin

Naringin (NA) is one of typical flavanone glycosides widely distributed in nature and possesses several biological activities including antioxidant, anti-inflammatory, and antiapoptotic. The aim of this study was to develop solid dispersion (SD) and to improve the dissolution rate and oral bioavailability of NA. NA-SD was prepared by the traditional preparation methods using PEG6000, F68, or PVP K30 as carrier at different drug to carrier ratios. According to the results of solubility and in vitro dissolution test, the NA-PEG6000 (1:3) SD was considered as an optimal formulation to characterize by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry and powder X-ray diffraction. Furthermore, oral bioavailabilities of NA-PEG6000 (1:3) SD and NA-suspension with the same dosage were investigated in SD rats. The results confirmed the formation of SD and the pharmacokinetic parameters of NA-PEG6000 (1:3) SD (C_max = 0.645 ± 0.262 µg/ml, AUC_0-t = 0.471 ± 0.084 µg/ml h) were higher than that of NA-suspension (C_max = 0.328 ± 0.183 µg/ml, AUC_0-t  = 0.361 ± 0.093 µg/ml h). Based on the results, the SD is considered as a promising approach to enhance the dissolution rate and oral bioavailability of NA.

Role of Plant-Derived Flavonoids and Their Mechanism in Attenuation of Alzheimer's and Parkinson's Diseases: An Update of Recent Data

Neurodegeneration is a progressive loss of neuronal cells in certain regions of the brain. Most of the neurodegenerative disorders (NDDs) share the communal characteristic such as damage or reduction of various cell types typically including astrocytes and microglial activity. Several compounds are being trialed to treat NDDs but they possess solitary symptomatic advantages along with copious side effects. The finding of more enthralling and captivating compounds to suspend and standstill the pathology of NDDs will be considered as a hallmark of present times. Phytochemicals possess the potential to alternate the synthetic line of therapy against NDDs. The present review explores the potential efficacy of plant-derived flavonoids against most common NDDs including Alzheimer's disease (AD) and Parkinson's disease (PD). Flavonoids are biologically active phytochemicals which possess potential pharmacological effects, including antiviral, anti-allergic, antiplatelet, anti-inflammatory, anti-tumor, anti-apoptotic and anti-oxidant effects and are able to attenuate the pathology of various NDDs through down-regulating the nitric oxide (NO) production, by reducing the tumor necrosis factor-α (TNF-α), by reducing the excitotoxicity of superoxide as well as acting as tyrosine kinase (TK) and monoamine oxidase (MAO) inhibiting enzyme.

Study on dose-dependent, frequency-dependent, and accumulative effects of 1.5 GHz and 2.856 GHz microwave on cognitive functions in Wistar rats

Many studies have revealed the cognitive decline induced by microwave radiation. However, the systematic study on dose-dependent, frequency-dependent and accumulative effects of microwave exposure at different frequencies was lacking. Here, we studied the relationship between the effects and the power and frequency of microwave and analyzed the accumulative effects of two different frequency microwaves with the same average power density. After microwave radiation, declines in spatial learning and memory and fluctuations of brain electric activities were found in the 10 mW/cm2 single frequency exposure groups and accumulative exposure groups. Meanwhile, morphological evidences in hippocampus also supported the cognitive dysfunction. Moreover, the decrease of Nissl contents in neurons indicated protein-based metabolic disorders in neurons. By detecting the key functional proteins of cholinergic transmitter metabolism, cytokines, energy metabolism and oxidative stress in the hippocampus, we found that microwave could lead to multiple metabolic disorders. Our results showed that microwave-induced cognitive decline was largely determined by its power rather than frequency. Injury effects were also found in accumulative exposure groups. We particularly concerned about the safety dose, injury effects and accumulative effects of microwaves, which might be very valuable in the future.

The use of antioxidant agents for chemotherapy-induced peripheral neuropathy treatment in animal models

Antineoplastic drugs such as cisplatin, oxaliplatin, paclitaxel and vincristin are widely used in the treatment of several solid and blood tumours. However, the severity of peripheral neuropathy caused by these agents can affect the patient's quality of life. The major symptoms of chemotherapy-induced peripheral neuropathy (CIPN) involve: sensory loss, paresthesia, dysesthaesia, numbness, tingling, temperature sensitivity, allodynia and hyperalgesia, in a "stocking and glove" distribution. Why many different chemotherapeutic agents result in similar neuropathy profiles is unclear. Many drug classes such as antidepressants, anticonvulsants, antispastic agents and others have been used in clinical practice, but there is no scientific evidence to prove their effectiveness. But drugs as the antioxidant have shown a protective effect against free radical damage. In order to find out a successful treatment for CIPN, animal studies (ie pharmacological and mechanical tests and histopathological immunohistochemical analyses) have been developed to try to determinate the action of the antioxidant agents. This review provides an overview of the major antioxidant agents recently investigated to treat CIPN and the animal models used for this purpose.

The beneficial role of Naringin- a citrus bioflavonoid, against oxidative stress-induced neurobehavioral disorders and cognitive dysfunction in rodents: A systematic review and meta-analysis

OBJECTIVES

Naringin is a bioflavonoid, very abundantly found in citrus species. In literature, naringin has been scientifically well documented for its beneficial effects in various neurological disorders. In this systematic review and meta-analysis, we have made an attempt to correlate the protective role of naringin against oxidative stress-induced neurological disorders in rodents.

METHODS

The systematic search was performed using electronic databases; the search was mainly focused on the role of naringin in oxidative stress-induced neuropathological conditions in rodents. While, the meta-analysis was performed on the effect of naringin on oxidative stress markers [superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), reduced glutathione (GSH), lipid peroxidation (LPO)], nitrite, mitochondrial complexes (I to IV) and enzymes (acetylcholinesterase, Na⁺-K⁺-ATPase, Ca²⁺-ATPase, and Mg²⁺-ATPase) in the rodent brain. The data was analyzed using Review Manager Software.

THE RESULTS

Based on the inclusion and exclusion criteria, twenty studies were selected. The meta-analysis revealed that, naringin could significantly inhibit various physical and chemical stimuli- induced neurological perturbances in the rodent brain, mediated through oxidative stress. Further, naringin also significantly restored the levels of all the oxidative stress markers (oxidative, nitrosative, enzymes, and mitochondrial complexes) in different parts of the rodent brain.

SUMMARY

This systematic review and meta-analysis supports the available scientific evidence on the beneficial role of naringin in the management of various neurological ailments. However, further studies involving human subjects is recommended to establish the safety and therapeutic efficacy in humans.

Therapeutic potential of naringin: an overview

CONTEXT

Naringin is a natural flavanone glycoside that is found in the Chinese herbal medicines and citrus fruits. Studies have demonstrated that naringin possesses numerous biological and pharmacological properties, but few reviews of these studies have been performed.

OBJECTIVE

The present review gathers the fragmented information available in the literature describing the extraction of naringin, its pharmacology and its controlled release formulations. Current research progress and the therapeutic potential of naringin are also discussed.

METHODS

A literature survey for relevant information regarding the biological and pharmacological properties of naringin was conducted using Pubmed, Sciencedirect, MEDLINE, Springerlink and Google Scholar electronic databases from the year 2007-2015.

RESULTS

Naringin modulates signalling pathways and interacts with signalling molecules and thus has a wide range of pharmacological activities, including anti-inflammatory, anti-cancer activities, as well as effects on bone regeneration, metabolic syndrome, oxidative stress, genetic damage and central nervous system (CNS) diseases. Information was gathered that showed the extraction of naringin can be improved using several modifications. There has been some progress in the development of controlled release formulations of naringin.

CONCLUSION

Naringin is a promising candidate for further in vivo studies and clinical use. More detailed studies regarding its mechanism of action are required.

Edaravone alleviates cisplatin-induced neurobehavioral deficits via modulation of oxidative stress and inflammatory mediators in the rat hippocampus

Cisplatin is a chemotherapeutic agent used in the treatment of malignant tumors. A major clinical limitation of cisplatin is its potential toxic effects, including neurotoxicity. Edaravone, a potent free radical scavenger, has been reported to have the neuroprotective effect against neurological deficits. The aim of the present study was to determine the neuroprotective effect of edaravone against cisplatin-induced behavioral and biochemical anomalies in male Wistar rats. Our results showed that cisplatin (5mg/kg/week, i.p.) administration for seven weeks caused marked cognitive deficits and motor incoordination in rats. This was accompanied by oxido-nitrosative stress, neuroinflammation, NF-κB activation and down-regulation of Nrf2/HO-1 gene expression level in the hippocampus. Edaravone (10mg/kg/week, i.p.) treatment for seven weeks inhibited the aforementioned neurobehavioral and neurochemical deficits. Furthermore, edaravone was found to up-regulate the gene expression level of Nrf2/HO-1 and prevented the cisplatin-induced NF-κB activation. These findings demonstrated that oxido-nitrosative stress and inflammatory signaling mediators play a key role in the development of cisplatin-induced neurobehavioral deficits which were prevented by edaravone treatment.

Toxic effects of cisplatin cytostatic drug in mussel Mytilus galloprovincialis

Antineoplastic drugs used in chemotherapy were detected in aquatic environment: despite the very low concentrations (ng L(-1) to ug L(-1)), due to their potent mechanism of action they could have adverse effects on non-target aquatic organisms particularly under chronic exposure. Cisplatin (CDDP) is one of the most effective anticancer drug currently in use but information on its ecotoxicological effects is very limited. In this study, Mytilus galloprovincialis was used to investigate the toxic effects related to CDDP exposure. Mussels were exposed to cisplatin (100 ng L(-1)) for 14 days: antioxidant (superoxide dismutase, catalase, total and selenium-dependent glutathione peroxidase) and phase II (glutathione-S-transferase) enzymes activities, oxidative damage (lipid peroxidation), genotoxicity (DNA damage) and neurotoxicity (acetylcholinesterase) was evaluated. Results indicate that CDDP at tested concentration induce changes in the antioxidant capacity, oxidative stress in target organs (digestive gland and gills) as well as DNA damage in mussel hemocytes and neurotoxicity representing a risk for non-target organisms.