Potent Natural Antioxidant Carveol Attenuates MCAO-Stress Induced Oxidative, Neurodegeneration by Regulating the Nrf-2 Pathway

Contribution of chemical permeation enhancers to the process of transdermal drug delivery: Adsorption, microscopic interactions, and mechanism

Transdermal drug delivery (TDD) has attracted widespread attention because of the advantage of its non-invasive nature, easy self-administration, and low side effects. The key to this pathway of drug delivery is how to overcome the barrier of the lipid matrix in the stratum corneum (SC). In this work, molecular dynamics (MD) were employed to investigate the adsorption of thyrotropin-releasing hormone (TRH) on the SC, and the effects of three different chemical permeation enhancers (ethanol (ETOH), carveol (CAV), and borneol (BOR)) on the SC were analyzed. The results showed that ETOH hardly altered the order of lipids in the SC, while CAV and BOR disrupted the morphology of the SC. The primary target of CAV was the CHOL in SC, which not only disrupted the ordered arrangement of CHOL, but also "extracted" CHOL from SC. The thickness distribution of SC became more inhomogeneous in the presence of CAV and BOR, which facilitated the penetration of drug molecules. Compared to no chemical permeation enhancers, the free energy of permeation in the presence of chemical permeation enhancers was less than 4-10 kcal mol-1, which suggested that chemical permeation enhancers were more favorable for the permeation of drugs from viewpoints of thermodynamics. All the results provided theoretical insights into the effect of chemical permeation enhancers on the transdermal permeation of drugs.

The Interplay of Carveol and All-Trans Retinoic Acid (ATRA) in Experimental Parkinson's Disease: Role of Inflammasome-Mediated Pyroptosis and Nrf2

Parkinson's disease (PD) is a debilitating and the second most common neurodegenerative disorder with a high prevalence. PD has a multifaceted etiology characterized by an altered redox state and an excessive inflammatory response. Extensive research has consistently demonstrated the role of the nuclear factor E2-related factor (Nrf2) and inflammasomes, notably NLRP3 in neurodegenerative diseases. In this study, our focus was on exploring the potential neuroprotective properties of carveol in Parkinson's disease. Our findings suggest that carveol may exhibit these effects through Nrf2 and by suppressing pyroptosis. Male albino mice were treated with carveol, and the animal PD model was induced through a single intranigral dose of 2 µg/2µl lipopolysaccharide (LPS). To further demonstrate the essential role of the Nrf2 pathway, we utilized all-trans retinoic acid (ATRA) to inhibit the Nrf2. Our finding showed the induction of pyroptosis as evidenced by increased levels of NLRP3 and other inflammatory mediators, including IL-1β, iNOS, p-NFKB, and apoptotic cell death indicated by positive fluoro Jade B (FJB) staining. Moreover, increased levels of lipid peroxides and reactive oxygen species indicated a significant rise in oxidative stress due to LPS. The administration of carveol mitigates oxidative stress and suppresses inflammatory pathways through the augmentation of intrinsic antioxidant defenses, primarily via the activation of the Nrf2. Conversely, ATRA reversed carveol protective effects by increasing FJB-positive cells, inflammatory and oxidative biomarkers. Taken together, our findings suggest that carveol mitigated LPS-induced Parkinson-like symptoms, partially through the activation of the Nrf2 and downregulation of pyroptosis notably NLRP3.

Elucidating the mechanisms of Buyang Huanwu Decoction in treating chronic cerebral ischemia: A combined approach using network pharmacology, molecular docking, and in vivo validation

OBJECTIVE

This study aimed to explore the potential mechanisms of Buyang Huanwu Decoction (BHD) in regulating the AKT/TP53 pathway and reducing inflammatory responses for the treatment of chronic cerebral ischemia (CCI) using UHPLC-QE-MS combined with network pharmacology, molecular docking techniques, and animal experiment validation.

METHODS

Targets of seven herbal components in BHD, such as Astragalus membranaceus, Paeoniae Rubra Radix, and Ligusticum chuanxiong, were identified through TCMSP and HERB databases. CCI-related targets were obtained from DisGeNET and Genecards, with an intersection analysis conducted to determine shared targets between the disease and the herbal components. Functional enrichment analysis of these intersecting targets was performed. Networks of gene ontology and pathway associations with these targets were constructed and visualized. A pharmacological network involving intersecting genes and active components was delineated. A protein-protein interaction network was established for these intersecting targets and visualized using Cytoscape 3.9.1. The top five genes from the PPI network and their corresponding active components underwent molecular docking. Finally, the 2-vessel occlusion (2-VO) induced CCI rat model was treated with BHD, and the network pharmacology findings were validated using Western blot, RT-PCR, behavioral tests, laser speckle imaging, ELISA, HE staining, Nissl staining, LFB staining, and immunohistochemistry and immunofluorescence.

RESULTS

After filtration and deduplication, 150 intersecting genes were obtained, with the top five active components by Degree value identified as Quercetin, Beta-Sitosterol, Oleic Acid, Kaempferol, and Succinic Acid. KEGG pathway enrichment analysis linked key target genes significantly with Lipid and atherosclerosis, AGE-RAGE signaling pathway, IL-17 signaling pathway, and TNF signaling pathway. The PPI network highlighted ALB, IL-6, AKT1, TP53, and IL-1β as key protein targets. Molecular docking results showed the strongest binding affinity between ALB and Beta-Sitosterol. Behavioral tests using the Morris water maze indicated that both medium and high doses of BHD could enhance spatial memory in 2-VO model rats, with high-dose BHD being more effective. Laser speckle results showed that BHD at medium and high doses could facilitate CBF recovery in CCI rats, demonstrating a dose-response relationship. HE staining indicated that all doses of BHD could reduce neuronal damage in the cortex and hippocampal CA1 region to varying extents, with the highest dose being the most efficacious. Nissl staining showed that nimodipine and medium and high doses of BHD could alleviate Nissl body damage. LFB staining indicated that nimodipine and medium and high doses of BHD could reduce the pathological damage to fiber bundles and myelin sheaths in the internal capsule and corpus callosum of CCI rats. ELISA results showed that nimodipine and BHD at medium and high doses could decrease the levels of TNF-α, IL-6, IL-17, and IL-1β in the serum of CCI rats (p < 0.05). Immunohistochemistry and immunofluorescence demonstrated that BHD could activate the AKT signaling pathway and inhibit TP53 in treating CCI. Western blot and RT-PCR results indicated that nimodipine and all doses of BHD could upregulate Akt1 expression and downregulate Alb, Tp53, Il-1β, and Il-6 expression in the hippocampus of CCI rats to varying degrees (p < 0.05).

CONCLUSION

BHD exerts therapeutic effects in the treatment of CCI by regulating targets, such as AKT1, ALB, TP53, IL-1β, and IL-6, and reducing inflammatory responses.

Pharmacological investigation of genistein for its therapeutic potential against nitroglycerin-induced migraine headache

OBJECTIVES

Migraine, typically occurs on one side of the head, lasts for hours to days. Trigemino-vascular system (TVS) plays a vital role in pain generation, with neurogenic inflammation and oxidative stress playing key roles in its pathophysiology.

METHODS

This study aimed to investigate genistein's potential as anti-inflammatory and anti-oxidant agent in mitigating migraine pain. Genistein (20 and 50 mg/kg) was administered intraperitoneally (IP) to nitroglycerin (NTG; 10 mg/kg)-induced migraine model in rats. Behavioral analysis, antioxidant assay, immunohistochemistry (IHC), histopathological examination, ELISA, and RT-PCR were conducted to evaluate the antimigraine potential of genistein.

KEY FINDINGS

In-silico analysis showed genestien's ACE values of -4.8 to -9.2 Kcal/mol against selected protein targets. Genistein significantly reversed mechanical and thermal nociception, light phobicity, and head scratching; increased the intensities of GST, GSH, catalase; and down regulated lipid peroxidase (LPO) in cortex and trigeminal nucleus caudalis (TNC). It also reduced Nrf2, NF-kB, and IL6 expression, analyzed through IHC, improved histopathological features, and increased COX-2 and decreased PPAR-γ expressions, while RT-PCR analysis revealed increased PPAR-γ expressions in genistein-treated rats.

CONCLUSION

Genistein exhibited potent antioxidant and anti-inflammatory properties in migraine treatment, acting through multifactorial mechanisms by modulating the expression of numerous proteins in the region cortex and TNC.

The Janus face of HIF-1α in ischemic stroke and the possible associated pathways

Stroke is the most devastating disease, causing paralysis and eventually death. Many clinical and experimental trials have been done in search of a new safe and efficient medicine; nevertheless, scientists have yet to discover successful remedies that are also free of adverse effects. This is owing to the variability in intensity, localization, medication routes, and each patient's immune system reaction. HIF-1α represents the modern tool employed to treat stroke diseases due to its functions: downstream genes such as glucose metabolism, angiogenesis, erythropoiesis, and cell survival. Its role can be achieved via two downstream EPO and VEGF strongly related to apoptosis and antioxidant processes. Recently, scientists paid more attention to drugs dealing with the HIF-1 pathway. This review focuses on medicines used for ischemia treatment and their potential HIF-1α pathways. Furthermore, we discussed the interaction between HIF-1α and other biological pathways such as oxidative stress; however, a spotlight has been focused on certain potential signalling contributed to the HIF-1α pathway. HIF-1α is an essential regulator of oxygen balance within cells which affects and controls the expression of thousands of genes related to sustaining homeostasis as oxygen levels fluctuate. HIF-1α's role in ischemic stroke strongly depends on the duration and severity of brain damage after onset. HIF-1α remains difficult to investigate, particularly in ischemic stroke, due to alterations in the acute and chronic phases of the disease, as well as discrepancies between the penumbra and ischemic core. This review emphasizes these contrasts and analyzes the future of this intriguing and demanding field.

Tannic acid inhibits pain mediators, inflammation and oxidative stress in mice exposed to glyphosate-based herbicide

Chronic exposure to glyphosate-based herbicide (Gly) has been associated with neurological disorders. Tannic acid (TA) is an antioxidant with attenuating action against neuroinflammation-associated conditions. This study evaluated the effect of Gly on pain perception alongside antinociceptive and anti-inflammatory actions of TA in Gly-exposed mice. Male Swiss mice were randomly divided into six groups (n=8): control (distilled water 0.2 ml/kg), Gly (Gly 500 mg/kg), Pre-TA + Gly (TA 50 mg/kg pre-treatment, afterwards Gly-administered), TA + Gly (TA 50 mg/kg and Gly co-administered), Pre-AA + Gly (ascorbic acid (AA) 10 mg/kg pre-treatment, afterwards Gly-administered), and AA + Gly (AA 10 mg/kg and Gly co-administered). Mechanical, thermal, and chemical pain were evaluated six weeks post vehicle/drugs administrations orally, followed by brain biochemical measurements. TA treatment alleviated Gly-induced hyperalgesia in similar version to the values of control and AA groups by increasing significantly (p < 0.05) nociceptive thresholds. Moreover, TA-treatment significantly decreased malondialdehyde (MDA) and pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6) levels, significantly increased anti-inflammatory cytokines (IL-10, IL-4, and TGF-1β) levels, and antioxidant enzymes, catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) activities compared to Gly-treated mice (p < 0.05). Conclusively, TA treatment exerted antinociceptive and anti-inflammatory actions, possibly through its antioxidant and anti-inflammatory actions in Gly-exposed mice. Notably, TA pre-treatment showed a better response than TA and Gly co-administration. We propose the potential neuroprotective and ameliorative functions of TA in Gly-induced hyperalgesia. This merits further clinical research into protective roles of TA against pesticide-related conditions.

Exploring the pathophysiological influence of heme oxygenase-1 on neuroinflammation and depression: A study of phytotherapeutic-based modulation

BACKGROUND

The heme oxygenase (HO) system plays a significant role in neuroprotection and reduction of neuroinflammation and neurodegeneration. The system, via isoforms HO-1 and HO-2, regulates cellular redox balance. HO-1, an antioxidant defense enzyme, is highlighted due to its association with depression, characterized by heightened neuroinflammation and impaired oxidative stress responses.

METHODOLOGY

We observed the pathophysiology of HO-1 and phytochemicals as its modulator. We explored Science Direct, Scopus, and PubMed for a comprehensive literature review. Bibliometric and temporal trend analysis were done using VOSviewer.

RESULTS

Several phytochemicals can potentially alleviate neuroinflammation and oxidative stress-induced depressive symptoms. These effects result from inhibiting the MAPK and NK-κB pathways - both implicated in the overproduction of pro-inflammatory factors - and from the upregulation of HO-1 expression mediated by Nrf2. Bibliometric and temporal trend analysis further validates these associations.

CONCLUSION

In summary, our findings suggest that antidepressant agents can mitigate neuroinflammation and depressive disorder pathogenesis via the upregulation of HO-1 expression. These agents suppress pro-inflammatory mediators and depressive-like symptoms, demonstrating that HO-1 plays a significant role in the neuroinflammatory process and the development of depression.

Quercetin attenuated ischemic stroke induced neurodegeneration by modulating glutamatergic and synaptic signaling pathways

Ischemic strokes originate whenever the circulation to the brain is interrupted, either temporarily or permanently, resulting in a lack of oxygen and other nutrients. This deprivation primarily impacts the cerebral cortex and striatum, resulting in neurodegeneration. Several experimental stroke models have demonstrated that the potent antioxidant quercetin offers protection against stroke-related damage. Multiple pathways have been associated with quercetin's ability to safeguard the brain from ischemic injury. This study examines whether the administration of quercetin alters glutamate NMDA and GluR1 receptor signaling in the cortex and striatum 72 h after transient middle cerebral artery occlusion. The administration of 10 mg/kg of quercetin shielded cortical and striatal neurons from cell death induced by ischemia in adult SD rats. Quercetin reversed the ischemia-induced reduction of NR2a/PSD95, consequently promoting the pro-survival AKT pathway and reducing CRMP2 phosphorylation. Additionally, quercetin decreased the levels of reactive oxygen species and inflammatory pathways while increasing the expression of the postsynaptic protein PSD95. Our results suggest that quercetin may be a promising neuroprotective drug for ischemic stroke therapy as it recovers neuronal damage via multiple pathways.

The cell-specific roles of Nrf2 in acute and chronic phases of ischemic stroke

Ischemic stroke refers to the sudden loss of blood flow in a specific area of the brain. It is the fifth leading cause of mortality and the leading cause of permanent disability. The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) controls the production of several antioxidants and protective proteins and it has been investigated as a possible pharmaceutical target for reducing harmful oxidative events in brain ischemia. Each cell type exhibits different roles and behaviors in different phases post-stroke, which is comprehensive yet important to understand to optimize management strategies and goals for care for stroke patients. In this review, we comprehensively summarize the protective effects of Nrf2 in experimental ischemic stroke, emphasizing the role of Nrf2 in different cell types including neurons, astrocytes, oligodendrocytes, microglia, and endothelial cells during acute and chronic phases of stroke and providing insights on the neuroprotective role of Nrf2 on each cell type throughout the long term of stroke care. We also highlight the importance of targeting Nrf2 in clinical settings while considering a variety of important factors such as age, drug dosage, delivery route, and time of administration.

Fluid shear stress induced-endothelial phenotypic transition contributes to cerebral ischemia-reperfusion injury and repair

Long-term ischemia leads to insufficient cerebral microvascular perfusion and dysfunction. Reperfusion restores physiological fluid shear stress (FSS) but leads to serious injury. The mechanism underlying FSS-induced endothelial injury in ischemia-reperfusion injury (IRI) remains poorly understood. In this study, a rat model of middle cerebral artery occlusion was constructed to explore cerebrovascular endothelial function and inflammation in vivo. Additionally, the rat brain microvascular endothelial cells (rBMECs) were exposed to a laminar FSS of 0.5 dyn/cm2 for 6 h and subsequently restored to physiological fluid shear stress level (2 dyn/cm2) for 2 and 12 h, respectively. We found that reperfusion induced endothelial-to-mesenchymal transition (EndMT) in endothelial cells, leading to serious blood-brain barrier dysfunction and endothelial inflammation, accompanied by the nuclear accumulation of Yes-associated protein (YAP). During the later stage of reperfusion, cerebral endothelium was restored to the endothelial phenotype with a distinct change in mesenchymal-to-endothelial transition (MEndT), while YAP was translocated and phosphorylated in the cytoplasm. Knockdown of YAP or inhibition of actin polymerization markedly impaired the EndMT in rBMECs. These findings suggest that ischemia-reperfusion increased intensity of FSS triggered an EndMT process and, thus, led to endothelial inflammation and tissue injury, whereas continuous FSS induced a time-dependent reversal MEndT event contributing to the endothelial repair. This study provides valuable insight for therapeutic strategies targeting IRI.

Andaliman (Zanthoxylum acanthopodium DC.) fruit ethanolic extract exerts attenuative effect on hyperglycemia, sensory and motoric function's disorders in alloxan-induced diabetic mice

Objective

Andaliman (Zanthoxylum acanthopodium) is a potent medicinal plant in Asia. This present study aimed to reveal the effectivity of Andaliman fruit extract in alleviating hyperglycemia, sensory and motoric balance disorders, histopathology of the cerebellum, and tissue oxidative stress in diabetic mice induced by alloxan.

Materials and Methods

Diabetes induction was performed by intraperitoneally injecting alloxan monohydrate [200 mg/kg body weight (BW)]. Subsequently, the mice were treated daily with an ethanolic extract of Andaliman fruit (0, 150, 300, 450 mg/kg BW per oral) for 28 days, followed by measurements of blood glucose, paw sensitivity, motoric balance, histopathology of the cerebellum, and malondialdehyde (MDA) levels. Moreover, the phytochemical constituents of the extract were elucidated by liquid chromatography.

Results

Higher doses of Andaliman fruit extract could significantly attenuate the elevation of random and fasting blood glucose (p < 0.05) and improve paw sensitivity responses (p < 0.05) and motoric balances (p < 0.05) in diabetic mice. Moreover, Andaliman fruit extract could significantly attenuate the degeneration of cerebellar Purkinje cells (p < 0.05) and suppress MDA levels in the blood (p < 0.05) while blunting the MDA in the brain tissue (p < 0.05). Phytochemical screening revealed 39 compounds in the Andaliman extract belonging to the groups of alkaloids (26 compounds), flavonoids (12 compounds), and terpenoids (1 compound).

Conclusion

The ethanolic extract of Andaliman fruit is capable of ameliorating diabetic neuropathy, motor balance disorders, and Purkinje cell degeneration while also reducing oxidative stress in the peripheral system. Hence, Andaliman extract is a promising candidate for formulation as an herbal remedy against the detrimental outcomes of diabetes mellitus.

Enhanced cardioprotective activity of ferulic acid-loaded solid lipid nanoparticle in an animal model of myocardial injury

Myocardial infarction results in an increased inflammatory and oxidative stress response in the heart, and reducing inflammation and oxidative stress after MI may offer protective effects to the heart. In the present study, we examined the cardioprotective effects of ferulic acid (FA) and ferulic acid nanostructured solid lipid nanoparticles (FA-SLNs) in an isoproterenol (ISO) induced MI model. Male Sprague Dawley rats were divided into five experimental groups to compare the effects of FA and FA-SLNs. The findings revealed that ISO led to extensive cardiomyopathy, characterized by increased infarction area, edema formation, pressure load, and energy deprivation. Additionally, ISO increased the levels of inflammatory markers (COX-2, NLRP3, and NF-кB) and apoptotic mediators such as p-JNK. However, treatment with FA and FA-SLNs mitigated the severity of the ISO-induced response, and elevated the levels of antioxidant enzymes while downregulating inflammatory pathways, along with upregulation of the mitochondrial bioenergetic factor PPAR-γ. Furthermore, virtual docking analysis of FA with various protein targets supported the in vivo results, confirming drug-protein interactions. Overall, the results demonstrated that FA-SLNs offer a promising strategy for protecting the heart from further injury following MI. This is attributed to the improved drug delivery and therapeutic outcomes compared to FA alone.

Isoquercitrin Played a Neuroprotective Role in Rats After Cerebral Ischemia/Reperfusion Through Up-Regulating Neuroglobin and Anti-Oxidative Stress

BACKGROUND

This study aims to investigate whether isoquercitrin (Iso) exerts a neuroprotective role effect after cerebral ischemia-reperfusion (CIR) via up-regulating neuroglobin (Ngb) or reducing oxidative stress.

METHODS

The middle cerebral artery occlusion/reperfusion (MCAO/R) model was constructed using Sprague Dawley rats. First, we divided 40 mice into 5 groups (n = 8): sham, MCAO/R, Low-dosed Iso (5 mg/kg Iso), Mid-dosed Iso (10 mg/kg Iso), and High-dosed Iso (20 mg/kg Iso). Then, 48 rats were separated into 6 groups (n = 8): sham, MCAO/R, Iso, artificial cerebrospinal fluid, Ngb antisense oligodeoxynucleotides (AS-ODNs), and AS-ODNs ± Iso. The effects of Iso on brain tissue injury and oxidative stress were evaluated using hematoxylin-eosin staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, immunofluorescence, western blotting, and real-time quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, and reactive oxygen species (ROS) detection.

RESULTS

The neurologic score, infarct volume, histopathology, apoptosis rate, and ROS production were reduced in Iso dose-dependent. The Ngb expression enhanced in Iso dose-dependent. The oxidative stress-related factors SOD, GSH, CAT, Nrf2, HO-1, and HIF-1α levels also increased in Iso dose-dependent, whereas the MDA levels decreased. However, related regulation of Iso on brain tissue damage and oxidative stress were reversed after low expression of Ngb.

CONCLUSION

Isoquercitrin played a neuroprotective role after CIR through up-regulating of Ngb and anti-oxidative stress.

Quercetin Alleviated Inflammasome-Mediated Pyroptosis and Modulated the mTOR/P70S6/P6/eIF4E/4EBP1 Pathway in Ischemic Stroke

Stroke ranks as the world's second most prevalent cause of mortality, and it represents a major public health concern with profound economic and social implications. In the present study, we elucidated the neuroprotective role of quercetin on NLRP3-associated pyroptosis, Nrf2-coupled anti-inflammatory, and mTOR-dependent downstream pathways. Male Sprague Dawley rats were subjected to 72 h of transient middle cerebral artery ischemia, followed by the administration of 10 mg/kg of quercetin. Our findings demonstrated that MCAO induced elevated ROS which were coupled to inflammasome-mediated pyroptosis and altered mTOR-related signaling proteins. We performed ELISA, immunohistochemistry, and Western blotting to unveil the underlying role of the Nrf2/HO-1 and PDK/AKT/mTOR pathways in the ischemic cortex and striatum. Our results showed that quercetin post-treatment activated the Nrf2/HO-1 cascade, reversed pyroptosis, and modulated the autophagy-related pathway PDK/AKT/mTOR/P70S6/P6/eIF4E/4EBP1. Further, quercetin enhances the sequestering effect of 14-3-3 and reversed the decrease in interaction between p-Bad and 14-3-3 and p-FKHR and 14-3-3. Our findings showed that quercetin exerts its protective benefits and rescues neuronal damage by several mechanisms, and it might be a viable neuroprotective drug for ischemic stroke therapy.

Ameliorative effect of carveol on scopolamine-induced memory impairment in rats

Objectives

Carveol is a naturally occurring terpenoid with antispasmodic, carminative, astringent, indigestion, and dyspepsia properties, as well as anti-diabetic, anti-oxidant, anti-hyperlipidemia, and anti-inflammatory properties in the liver. Research also suggests that it has memory-enhancing and anti-oxidant properties. The purpose of this research was to see whether carveol could protect rats against scopolamine-induced memory loss in a rat model.

Materials and Methods

Thirty male Sprague-Dawley rats (200-250 g) were grouped as the saline group receiving saline, disease group receiving scopolamine, and four treatment groups among which three groups received scopalamine+carveol and one group received scopalamine+donepezil for 28 days. Followed by in vitro, behavioral, anti-oxidant, and molecular studies were done. P<0.005 was considered statistically significant.

Results

The in vitro assay showed that carveol caused diphenyl-1-picrylhydrazyl inhibition. In-vivo findings revealed that carveol (50, 100, and 200 mg/kg) significantly improved dementia by reducing escape latency and spending more time in the targeted quadrant in the Morris water maze test. Increased number of entries and percent spontaneous alterations were observed in rats' Y-maze test. In animal brain tissues, i.e., cortex and hippocampus, carveol enhanced glutathione, glutathione-s-transferase, catalase, and reduced lipid peroxide levels. Carveol also improved cellular architecture in histopathological examinations and decreased expression of inflammatory markers such as amyloid-beta, nuclear factor kappa light chain activated B cells, tumor necrosis factor-alpha, cyclooxygenase 2, prostaglandin E2, and interleukin-18, as evidenced by immunohistochemistry and enzyme-linked immunosorbent assays, as well as molecular investigations.

Conclusion

This study suggests that the compound could be potent against amnesia mediated through anti-oxidant, amyloid-beta inhibition, and anti-inflammatory pathways.

Momordica charantia polysaccharide ameliorates D-galactose-induced aging through the Nrf2/β-Catenin signaling pathway

Aging is widely thought to be associated with oxidative stress. Momordica charantia (MC) is a classic vegetable and traditional herbal medicine widely consumed in Asia, and M. charantia polysaccharide (MCP) is the main bioactive ingredient of MC. We previously reported an antioxidative and neuroprotective effect of MCP in models of cerebral ischemia/reperfusion and hemorrhage injury. However, the role played by MCP in neurodegenerative diseases, especially during aging, remains unknown. In this study, we investigated the protective effect of MCP against oxidative stress and brain damage in a D-galactose-induced aging model (DGAM). The Morris water maze test was performed to evaluate the spatial memory function of model rats. The levels of malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) were measured and telomerase activity was determined. The results showed that MCP treatment attenuated spatial memory dysfunction induced by D-galactose. In addition, MCP increased antioxidant capacity by decreasing MDA and increasing SOD and GSH levels. MCP treatment also improved telomerase activity in aging rats. Mechanistically, MCP promoted the entry of both Nrf2 and β-Catenin into the nucleus, which is the hallmark of antioxidation signaling pathway activation. This study highlights a role played by MCP in ameliorating aging-induced oxidative stress injury and reversing the decline in learning and memory capacity. Our work provides evidence that MCP administration might be a potential antiaging strategy.

A Review on Therapeutic Potential of Natural Phytocompounds for Stroke

Stroke is a serious condition that results from an occlusion of blood vessels that leads to brain damage. Globally, it is the second highest cause of death, and deaths from strokes are higher in older people than in the young. There is a higher rate of cases in urban areas compared to rural due to lifestyle, food, and pollution. There is no effective single medicine for the treatment of stroke due to the multiple causes of strokes. Thrombolytic agents, such as alteplase, are the main treatment for thrombolysis, while multiple types of surgeries, such ascraniotomy, thrombectomy, carotid endarterectomy, and hydrocephalus, can be performed for various forms of stroke. In this review, we discuss some promising phytocompounds, such as flavone C-glycoside (apigenin-8-C-β-D-glucopyranoside), eriodictyol, rosamirinic acid, 6″-O-succinylapigenin, and allicin, that show effectiveness against stroke. Future study paths are given, as well as suggestions for expanding the use of medicinal plants and their formulations for stroke prevention.

MicroRNA‑27a Aggravates Ferroptosis during early Ischemic Stroke of Rats Through Nrf2

Ischaemic stroke (IS) is characterized by high morbidity, disability and mortality and lacks effective solutions. MiRNA-27a has been implicated in ferroptosis, but evidence that miRNA-27a regulates ferroptosis in ischaemic stroke is lacking. Nrf2 could reduce brain tissue injury in ischaemic stroke and resist ferroptosis. The current study aimed to investigate the relationship between miRNA-27a/Nrf2 and ferroptosis in ischaemic stroke. In this study, IS was simulated using a permanent middle cerebral artery occlusion (pMCAO) model. The degree of brain tissue injury was assessed by conducting TTC staining and neurological function scoring. MiRNA-27a expression levels were altered via the intracerebroventricular injection of miRNA‑27a agonist or antagonist. Glutathione peroxidase 4 (GPX4), glutathione (GSH), Fe and malondialdehyde (MDA) are considered biomarkers for ferroptosis. The expression of GPX4 and Nrf2 was analysed by Western blot assay. The GSH, Fe and MDA contents were detected by detection kits. We found that the expression levels of Fe and MDA were increased, while GPX4 and GSH were decreased in the pMCAO groups compared with the control group. These results indicated that ferroptosis intensified over time during IS. In addition, the miRNA‑27a agonist significantly aggravated ferroptosis and reduced neurological function scores compared with those of the control group. Subsequently, a luciferase reporter gene system verified the targeted binding of miRNA‑27a to Nrf2. The results showed that miRNA‑27a inhibited Nrf2 in a targeted manner, which also exacerbated the extent of ferroptosis. However, the miRNA‑27a antagonist reversed the miR‑27a agonist‑mediated effects. Therefore, the present study indicated that miRNA‑27a may aggravate brain tissue ferroptosis during ischaemic stroke, potentially by inhibiting Nrf2.

Improved biopharmaceutical performance of antipsychotic drug using lipid nanoparticles via intraperitoneal route

This study aims to develop, characterize, and examine olanzapine-loaded solid lipid nanocarriers (OLAN-SLNs) for effective brain delivery. OLAN has poor water solubility and low penetration through blood-brain barrier (BBB). Herein, OLAN-SLNs were fabricated using high-pressure homogenization (HPH) method followed by their investigation for particle properties. Moreover, in vitro release and in vivo pharmacokinetics profiles of OLAN-SLNs were compared with pure drug. Anti-psychotic activity was performed in LPS-induced psychosis mice model. Furthermore, expressions of the COX-2 and NF-κB were measured trailed by histopathological examination. The optimized formulation demonstrated nanoparticle size (149.1 nm) with rounded morphology, negative zeta potential (-28.9 mV), lower PDI (0.334), and excellent entrapment efficiency (95%). OLAN-SLNs significantly retarded the drug release and showed sustained release pattern as compared to OLAN suspension. Significantly enhanced bioavailability (ninefold) was demonstrated in OLAN-SLNs when compared with OLAN suspension. Behavioral tests showed significantly less immobility and more struggling time in OLAN-SLNs treated mice group. Additionally, reduced expression of COX-2 and -NF κB in brain was found. Altogether, it can be concluded that SLNs have the potential to deliver active pharmaceutical ingredients to brain, most importantly to enhance their bioavailability and antipsychotic effect, as indicated for OLAN in this study.

Novel Isoxazole Derivative Attenuates Ethanol-Induced Gastric Mucosal Injury through Inhibition of H+/K+-ATPase Pump, Oxidative Stress and Inflammatory Pathways

Isoxazole derivatives are significant enough due to their wide range of pharmacological and therapeutic activities. The purpose of the current study is to use computational, in vitro, in vivo, and extensive molecular approaches to examine the possible anti-ulcer activity of 4-benzylidene-3 methyl-1,2-isoxazol-5(4H)-one (MBO). Biovia Discovery Studio visualizer (DSV) was utilized for virtual screening. A tissue antioxidant investigation, H⁺/K⁺-ATPase test, and anti-H. pylori activities were carried out. ELISA, immunohistochemistry, and PCR methods were employed for the proteome analysis. An ethanol-induced stomach ulcer model was used to examine the anti-ulcer potential in rats. The binding affinities for MBO ranged from −5.4 to −8.2 Kcal/mol. In vitro findings revealed inhibitory activity against H. pylori and the H⁺/K⁺-ATPase pump. It also enhanced levels of glutathione, catalase, and glutathione-S-transferase and reduced lipid peroxidation levels in gastric tissues of rats. In vivo results showed the gastro-protective effect of MBO (30 mg/kg) in ulcerative rat stomachs. The proteomic study revealed decreased expression of inflammatory markers (cyclooxygenase-2, p-NFkB, and TNF-α). In RT-PCR analysis, the expression levels of H⁺/K⁺-ATPase were reduced. Furthermore, ADMET (absorption, distribution, metabolism, excretion and toxicity) studies revealed that MBO has high GIT solubility and has a safer profile for cardiac toxicity. This study suggests that MBO displayed anti-ulcer potential, which may have been mediated through the inhibition of the H⁺/K⁺-ATPase pump, as well as antioxidant and anti-inflammatory pathways. It has the potential to be a lead molecule in the treatment of peptic ulcers with fewer adverse effects.

Neuroprotective effects of mild hypothermia against traumatic brain injury by the involvement of the Nrf2/ARE pathway

BACKGROUND

Traumatic brain injury (TBI) is the leading cause of death and disability worldwide. Mild hypothermia (32-35°C) has been found to show neuroprotective effects against TBI. However, the specific mechanism is still elusive. In the current study, we explored the relationship between oxidative damage after TBI and treatment with mild hypothermia as well as the underlying molecular mechanisms.

METHODS

We used the closed cortex injury model to perform the brain injury and a temperature monitoring and control system to regulate the body temperature of mice after injury. Adult male C57BL/6 mice were adopted in this study and divided into four experimental groups. Tissue samples were harvested 24 h after injury.

RESULTS

First, our results showed that treatment with mild hypothermia significantly improved neurobehavioral dysfunction and alleviated brain edema after TBI. Moreover, treatment with mild hypothermia enhanced the activity of the antioxidant enzymes superoxide dismutase and glutathione peroxidase and reduced the accumulation of lipid peroxidation malondialdehyde. Importantly, the expression and activation of the nuclear factor erythroid 2-related factor 2-antioxidant response element (Nrf2-ARE) pathway were upregulated by mild hypothermia after TBI. Finally, treatment with hypothermia significantly decreased the cell apoptosis induced by TBI.

CONCLUSION

Our results showed that the protective effects of mild hypothermia after TBI may be achieved by the upregulation of the Nrf2-ARE pathway and revealed Nrf2 as a potentially important target to improve the prognosis of TBI.

Identification of novel and potential PPARγ stimulators as repurposed drugs for MCAO associated brain degeneration

Peroxisome proliferator-activated receptor-gamma (PPARγ) has been shown to have therapeutic promise in the treatment of ischemic stroke and is supported by several studies. To identify possible PPARγ activators, the current study used an in silico technique in conjunction with molecular simulations and in vivo validation. FDA-approved drugs were evaluated using molecular docking to determine their affinity for PPARγ. The findings of molecular simulations support the repurposing of rabeprazole and ethambutol for the treatment of ischemic stroke. Adult Sprague Dawley rats were subjected to transient middle cerebral artery occlusion (t-MCAO). Five groups were made as a sham-operated, t-MCAO group, rabeprazole +t-MCAO, ethambutol +t-MCAO, and pioglitazone +t-MCAO. The neuroprotective effects of these drugs were evaluated using the neurological deficit score and the infarct area. The inflammatory mediators and signaling transduction proteins were quantified using Western blotting, ELISA, and immunohistochemistry. The repurposed drugs mitigated cerebral ischemic injury by PPARγ mediated downregulation of nods like receptor protein 3 inflammasomes (NLRP3), tumor necrosis factor-alpha (TNF-α), cyclooxygenase 2 (COX-2), nuclear factor kappa-light-chain-enhancer of activated B cells (p-NF-kB), and c-Jun N-terminal kinase (p-JNK). Our data demonstrated that rabeprazole and ethambutol have neuroprotective potential via modulating the cytoprotective stress response, increasing cellular survival, and balancing homeostatic processes, and so may be suitable for future research in stroke therapy.

Carvacrol Alleviates Hyperuricemia-Induced Oxidative Stress and Inflammation by Modulating the NLRP3/NF-κB Pathwayt

Purpose

Gouty arthritis is generally induced by the accumulation of monosodium urate (MSU) crystals in the joints due to elevated serum uric acid levels, potentially leading to serious pathological disorders such as nephrolithiasis, renal failure, and acute gouty arthritis. In this study, we aimed to validate the anti-gout effects of carvacrol, a phenolic monoterpene.

Materials and Methods

Male Sprague–Dawley rats were divided into normal saline, disease group by injecting potassium mono-oxonate (PO) at a dose of 250 mg/kg, and three treatment groups, either with carvacrol 20 mg/kg or 50 mg/kg and 10 mg/kg allopurinol. The blood and tissue samples were subsequently collected and analyzed using different biochemical and histopathological techniques.

Results

Our results revealed a significant increase in the serum levels of oxidative stress-related markers, namely, uric acid and C-reactive protein (CRP), and NLRP3 inflammasome-dependent inflammatory mediators, including nuclear factor kappa B (NF-κB) and tumor necrosis factor-alpha (TNF-α). Carvacrol administration for seven consecutive days exhibited significant anti-hyperuricemic and anti-inflammatory effects in a dose-dependent manner. Notably, the 50 mg/kg carvacrol treatment was observed to produce results similar to the allopurinol treatment. Furthermore, the renal safety of carvacrol was confirmed by the renal function test.

Conclusion

Carvacrol potentially alleviates hyperuricemia-induced oxidative stress and inflammation by regulating the ROS/NRLP3/NF-κB pathway, thereby exerting protective effects against joint degeneration.

Engineered Neutral Phosphorous Dendrimers Protect Mouse Cortical Neurons and Brain Organoids from Excitotoxic Death

Nanoparticles are playing an increasing role in biomedical applications. Excitotoxicity plays a significant role in the pathophysiology of neurodegenerative diseases, such as Alzheimer’s or Parkinson’s disease. Glutamate ionotropic receptors, mainly those activated by N-methyl-D-aspartate (NMDA), play a key role in excitotoxic death by increasing intraneuronal calcium levels; triggering mitochondrial potential collapse; increasing free radicals; activating caspases 3, 9, and 12; and inducing endoplasmic reticulum stress. Neutral phosphorous dendrimers, acting intracellularly, have neuroprotective actions by interfering with NMDA-mediated excitotoxic mechanisms in rat cortical neurons. In addition, phosphorous dendrimers can access neurons inside human brain organoids, complex tridimensional structures that replicate a significant number of properties of the human brain, to interfere with NMDA-induced mechanisms of neuronal death. Phosphorous dendrimers are one of the few nanoparticles able to gain access to the inside of neurons, both in primary cultures and in brain organoids, and to exert pharmacological actions by themselves.

Carveol Promotes Nrf2 Contribution in Depressive Disorders through an Anti-inflammatory Mechanism

Major depressive disorder (MDD) is a progressive deteriorating mental state with a feeling of worthlessness and frequent mood swings. Several studies reported the favorable effects of natural drug substances on MMD associated oxidative stress and neuroinflammation. The present study is attempted to examine whether carveol could affect lipopolysaccharide- (LPS-) induced depression, and if so, how nuclear factor E2-related factor (Nrf2) contributed to the neuroprotective effects of carveol mechanistically. Two experimental cohorts were used using the SD rats: first to evaluate the promising dose of carveol (whether 20 mg/kg or 50 mg/kg) and secondly to determine the effect of carveol on Nrf2-mediated antidepression. Significant neuronal alterations were noticed in the cortex and hippocampus regions in the LPS-treated group, accompanied by elevated inflammatory cytokine levels such as tumor necrosis factor-alpha (TNF-α), cyclooxygenase (COX-2), and c-Jun N-terminal kinase (p-JNK). Moreover, amassing of free radicals exacerbated lipid peroxidase (LPO) and oxidative stress with a limited antioxidant capacity. Carveol (20 mg/kg) significantly ameliorated these detrimental effects by promoting the antioxidant Nrf2 gene and protein, which critically regulate the downstream antioxidant and anti-inflammatory pathway. To further elaborate our hypothesis, we employed all-trans retinoic acid (ATRA), an Nrf2 inhibitor, and we found that ATRA exaggerated LPS-induced depressive-like effects associated with elevated neuroinflammatory markers. Our results demonstrated that carveol (20 mg/kg) could activate the endogenous antioxidant Nrf2, which regulates the downstream antioxidant signaling pathway, eventually leading to amelioration of LPS-induced neuroinflammation and neurodegeneration.

1,3,4, Oxadiazole Compound A3 Provides Robust Protection Against PTZ-Induced Neuroinflammation and Oxidative Stress by Regulating Nrf2-Pathway

Background

Epilepsy is a common neurological disorder that is characterized by recurrent episodes of seizures. Various studies have demonstrated a direct association between oxidative stress and inflammation in several neurological disorders including epilepsy. This study aimed to investigate the neuroprotective effects of a synthetic 1,3,4, oxadiazole compound A3 against pentylenetetrazole (PTZ)-induced kindling and seizure model.

Methodology

PTZ was administered in a sub-convulsive dose of 40 mg/kg for 15 days, at 48-hour intervals to male Swiss-Albino mice until animals were fully kindled. Two different doses of A3 (10 mg/kg and 30 mg/kg) were administered to find out the effective dose of A3 and to further demonstrate the relative role of nuclear factor E2-related factor (Nrf2) in the PTZ-induced kindled model.

Results

Our results demonstrated a compromised antioxidant capacity associated with a low level of catalase (CAT), superoxide dismutase (SOD), glutathione (GST), and glutathione S-transferase (GSH) in the kindled group. However, the PTZ-induced group demonstrated an elevated level of lipid peroxidation (LPO) level parallel to pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), mediators as cyclooxygenase (COX-2), and nuclear factor kappa B (NFκB). Furthermore, the A3 treatment reversed these changes and overexpressed the antioxidant Nrf2 gene and its downstream HO-1. To further investigate the involvement of Nrf2, we employed an Nrf2-inhibitor, ie, all-trans retinoic acid (ATRA), that further aggravated the PTZ toxicity. Moreover, vascular endothelial growth factor (VEGF) expression was evaluated to assess the extent of BBB disruption.

Conclusion

The findings of this study suggest that A3 could mediate neuroprotection possibly by activating Nrf2 dependent downregulation of inflammatory cascades.

The Effects of Modified Curcumin Preparations on Glial Morphology in Aging and Neuroinflammation

Neuroinflammation is characterized by reactive microglia and astrocytes (collectively called gliosis) in the central nervous system and is considered as one of the main pathological hallmarks in different neurodegenerative diseases such as Alzheimer's disease, age-related dementia, and multiple sclerosis. Upon activation, glia undergoes structural and morphological changes such as the microglial cells swell in size and astrocytes become bushy, which play both beneficial and detrimental roles. Hence, they are unable to perform the normal physiological role in brain immunity. Curcumin, a cytokine suppressive anti-inflammatory drug, has a high proven pre-clinical potency and efficacy to reverse chronic neuroinflammation by attenuating the activation and morphological changes that occur in the microglia and astrocytes. This review will highlight the recent findings on the tree structure changes of microglia and astrocytes in neuroinflammation and the effects of curcumin against the activation and morphology of glial cells.

Bioactive properties of the aromatic molecules of spearmint (Mentha spicata L.) essential oil: a review

Spearmint belongs to the genus Mentha in the family Labiateae (Lamiaceae), which is wildly cultivated worldwide for its remarkable aroma and commercial value. The aromatic molecules of spearmint essential oil,...

RETRACTED: Melatonin rescues the mice brain against cisplatin-induced neurodegeneration, an insight into antioxidant and anti-inflammatory effects

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editors-in-Chief. Figure 1C appears similar to Figure 5h of the article published by Oxidative Medicine and Cellular Longevity 2021 (2021) Article ID 6635552 https://doi.org/10.1155/2021/6635552, Figure 5a of the article published by Cells 10 (2021) 2719 https://doi.org/10.3390/cells10102719 and Figure 8a of the article published by Molecular Neurobiology 56 (2019) 6293–6309 https://doi.org/10.1007/s12035-019-1512-7. Although this article was published earlier than the Cells article, the Editors decided to retract this article given concerns about the reliability of the data. Also, sections of panels within Figures 1H and 2G appear similar to each other. The journal records indicated that the names of the authors Reem Alshaman and Muhammad Imran Khan were added to the revised version of the article without exceptional approval by the handling Editor, which is contrary to the journal policy on changes to authorship.

Bergapten Attenuates Nitroglycerin-Induced Migraine Headaches through Inhibition of Oxidative Stress and Inflammatory Mediators

The present study intended to examine the effect of bergapten and possible mechanisms involved in the treatment of migraine-associated symptoms in the rat model. Five doses of nitroglycerin (10 mg/kg) were injected intraperitoneal to induce migraine headaches in rats with a one-day break between each dose. Treatment groups received nitroglycerin followed after 1 day by bergapten (50 or 100 mg/kg), saline (10 mL/kg), or sumatriptan (50 mg/kg) once daily for 10 days. Behavioral observations were analyzed 2 h after nitroglycerin injections and 1 h 40 min after treatment. The animals were sacrificed 24 h after the last treatment dose. Samples of trigeminal nucleus caudalis (TNC) and cerebral cortex were collected and analyzed for antioxidant activity and expression of inflammatory markers by immunohistochemistry and enzyme-linked immunosorbent assay. Our findings revealed that bergapten notably decreases headache by altering mechanical allodynia, thermal allodynia, light phobicity, and the number of head-scratching incidence in rats. In the cortex and TNC regions, antioxidant factors were restored, and lipid peroxidation was significantly reduced. Furthermore, bergapten decreased the expression of inflammatory markers, such as nuclear factor kappa B (NF-Kb) and tumor necrosis factor-alpha (TNF-α), as evidenced by immunohistochemistry and ELISA. These results suggest that bergapten exhibits headache-relieving activity, possibly mediated through antioxidant and anti-inflammatory pathways.

Carveol Attenuates Seizure Severity and Neuroinflammation in Pentylenetetrazole-Kindled Epileptic Rats by Regulating the Nrf2 Signaling Pathway

Epilepsy is a neurodegenerative brain disorder characterized by recurrent seizure attacks. Numerous studies have suggested a strong correlation between oxidative stress and neuroinflammation in several neurodegenerative disorders including epilepsy. This study is aimed at investigating the neuroprotective effects of the natural compound carveol against pentylenetetrazole- (PTZ-) induced kindling and seizure model. Two different doses of carveol (10 mg/kg and 20 mg/kg) were administered to male rats to determine the effects and the effective dose of carveol and to further demonstrate the mechanism of action of nuclear factor E2-related factor (Nrf2) in PTZ-induced kindling model. Our results demonstrated reduced levels of innate antioxidants such as superoxide dismutase (SOD), catalase, glutathione-S-transferase (GST), and glutathione (GSH), associated with elevated lipid peroxidation (LPO) and inflammatory cytokines level such as tumor necrosis factor-alpha (TNF-α), and mediators like cyclooxygenase (COX-2) and nuclear factor kappa B (NFκB). These detrimental effects exacerbated oxidative stress and provoked a marked neuronal alteration in the cortex and hippocampus of PTZ-intoxicated animals that were associated with upregulated Nrf2 gene expression. Furthermore, carveol treatment positively modulated the antioxidant gene Nrf2 and its downstream target HO-1. To further investigate the role of Nrf2, an inhibitor of Nrf2 called all-trans retinoic acid (ATRA) was used, which further exacerbated PTZ toxicity. Moreover, carveol treatment induced cholinergic system activation by mitigating acetylcholinesterase level which is further linked to attenuated neuroinflammatory cascade. The extent of blood-brain barrier disruption was evaluated based on vascular endothelial growth factor (VEGF) expression. Taken together, our findings suggest that carveol acts as an Nrf2 activator and therefore induces downstream antioxidants and mitigates inflammatory insults through multiple pathways. This eventually alleviates PTZ-induced neuroinflammation and neurodegeneration.

The Nrf2 Pathway in Ischemic Stroke: A Review

Ischemic stroke, characterized by the sudden loss of blood flow in specific area(s) of the brain, is the leading cause of permanent disability and is among the leading causes of death worldwide. The only approved pharmacological treatment for acute ischemic stroke (intravenous thrombolysis with recombinant tissue plasminogen activator) has significant clinical limitations and does not consider the complex set of events taking place after the onset of ischemic stroke (ischemic cascade), which is characterized by significant pro-oxidative events. The transcription factor Nuclear factor erythroid 2-related factor 2 (Nrf2), which regulates the expression of a great number of antioxidant and/or defense proteins, has been pointed as a potential pharmacological target involved in the mitigation of deleterious oxidative events taking place at the ischemic cascade. This review summarizes studies concerning the protective role of Nrf2 in experimental models of ischemic stroke, emphasizing molecular events resulting from ischemic stroke that are, in parallel, modulated by Nrf2. Considering the acute nature of ischemic stroke, we discuss the challenges in using a putative pharmacological strategy (Nrf2 activator) that relies upon transcription, translation and metabolically active cells in treating ischemic stroke patients.

Pharmacological evaluation of continentalic acid for antidiabetic potential

BACKGROUND

Diabetes is a complex endocrine and metabolic disorder. Continentalic acid is a natural drug product found in roots of Aralia continentalis (family Araliaceae), which used in traditional medicine for treatment of rheumatic arthritis, lumbag, lameness, inflammation, gastritis, nephritis and diabetes mellitus.

PURPOSE

This study is aim to investigate the continentalic acid anti-diabetic potential.

METHODS

In-silico, in-vitro, in-vivo and molecular techniques were used to investigate various effects of continentalic acid by Auto Doc Vina, α-amylase and α-glucosidase inhibitory assay and alloxan-induced diabetes rats model.

RESULTS

In-silico results revealed that continentalic acid exhibits binding energy values of - 5 to - 9.3Kcal/mol against selected targets. In-vitro assay showed that continentalic acid caused α-amylase and α-glucosidase enzymes inhibition. In-vivo finding exhibits that continentalic acid (50 mg/kg) decreased blood glucose level, body weight, oral glucose tolerance overload, glycosylated hemoglobin, triglycerides, total cholesterol, low density lipoprotein, aspartate transaminase, aspartate aminotransferase, alkaline phosphate, total bilirubin and increased high density lipoprotein (P < 0.05, P < 0.01, P < 0.001 vs. diabetic control group). In animals pancreas and liver tissues, continentalic acid enhanced glutathione-s-transferase, reduced glutathione, catalase and decreased lipid hydroperoxide level, improved cellular architecture in histopathological examination and decrease expression of inflammatory markers: cyclooxygenase 2, tumor necrosis factor alpha, phosphorylated-nuclear factor kappa B, prostaglandins E2, interleukin-18 and increased heme oxygenase-1, as evidenced in immunohistochemistry and enzyme-linked immunosorbent assay molecular investigations.

CONCLUSIONS

This study shows that continentalic acid exhibited binding affinities against the different targets and anti-diabetic action, mediated possibly through α-amylase and α-glucosidase inhibition, anti-hyperlipidemic, hepatoprotection, antioxidant and anti-inflammatory pathways.

Enhanced neuroprotective and antidepressant activity of curcumin-loaded nanostructured lipid carriers in lipopolysaccharide-induced depression and anxiety rat model

The present study aims to develop curcumin-loaded nanostructured lipid carriers (CUR-NLCs) and investigate their neuroprotective effects in lipopolysaccharide (LPS)-induced depression and anxiety model. Nanotemplate engineering technique was used to prepare CUR-NLCs with Compritol 888 ATO and oleic acid as solid and liquid lipid, respectively. Poloxamer 188, Tween 80 and Span 80 were used as stabilizing agents for solid-liquid lipid core. The physicochemical parameters of CUR-NLCs were determined followed by in vitro drug release and in vivo neuroprotective activity in rats. The optimized CUR-NLCs demonstrated nanometric particle size of 147.8 nm, surface charge of -32.8 mV and incorporation efficiency of 91.0%. CUR-NLCs showed initial rapid followed by a sustained drug release reaching up to 73% after 24 h. CUR-NLCs significantly elevated struggling time and decreased immobility time in forced swim and tail suspension tests. A substantial increase in time spent and number of entries into the light and open compartments was observed in light-dark box and elevated plus maze models. CUR-NLCs improved the tissue architecture and suppressed the expression of p-NF-κB, TNF-α and COX-2 in brain tissues from histological and immunohistochemical analysis. CUR-NLCs improved the neuroprotective effect of curcumin and can be used as a potential therapeutics for depression and anxiety.

Natural Dietary Supplement, Carvacrol, Alleviates LPS-Induced Oxidative Stress, Neurodegeneration, and Depressive-Like Behaviors via the Nrf2/HO-1 Pathway

PURPOSE

Major depressive disorder (MDD) is a debilitating human health condition characterized by mood swings and is associated with a high probability of suicide attempts. Several studies have reported a role of neuroinflammation in MMD, yet the efficacy of natural drug substances on neuroinflammation-associated depression has not been well-investigated. The present study examined the neuroprotective effects of carvacrol on lipopolysaccharide (LPS)-induced neuroinflammation, depression, and anxiety-like behavior.

METHODS

Male Sprague Dawley rats were divided into two experimental cohorts to determine the effects and the effective dose of carvacrol (whether 20 mg/kg or 50 mg/kg), and further demonstrate the mechanism of action of nuclear factor E2-related factor (Nrf2) in depression.

RESULTS

We found marked neuronal alterations in the cortex and hippocampus of LPS-intoxicated animals that were associated with higher inflammatory cytokine expression such as cyclooxygenase (COX2), tumor necrosis factor-alpha (TNF-α), and c-Jun N-terminal kinase (p-JNK). These detrimental effects exacerbated oxidative stress, as documented by a compromised antioxidant system due to high lipid peroxidase (LPO). Carvacrol (20 mg/kg) significantly reverted these changes by positively modulating the antioxidant gene Nrf2, a master regulator of the downstream antioxidant pathway. To further investigate the role of Nrf2, an inhibitor of Nrf2 called all-trans retinoic acid (ATRA) was used, which further exacerbated LPS toxicity with a higher oxidative and inflammatory cytokine level. To further support our notion, we performed virtual docking of carvacrol with the Nrf2-Keap1 target and the resultant drug-protein interactions validated the in vivo findings.

CONCLUSION

Collectively, our findings suggest that carvacrol (20 mg/kg) could activate the endogenous master antioxidant Nrf2, which further regulates the expression of downstream antioxidants, eventually ameliorating LPS-induced neuroinflammation and neurodegeneration.

Taurine Protects against Postischemic Brain Injury via the Antioxidant Activity of Taurine Chloramine

Taurine is ubiquitously distributed in mammalian tissues and is highly concentrated in the heart, brain, and leukocytes. Taurine exerts neuroprotective effects in various central nervous system diseases and can suppress infarct formation in stroke. Taurine reacts with myeloperoxidase (MPO)-derived hypochlorous acid (HOCl) to produce taurine chloramine (Tau-Cl). We investigated the neuroprotective effects of taurine using a rat middle cerebral artery occlusion (MCAO) model and BV2 microglial cells. Although intranasal administration of taurine (0.5 mg/kg) had no protective effects, the same dose of Tau-Cl significantly reduced infarct volume and ameliorated neurological deficits and promoted motor function, indicating a robust neuroprotective effect of Tau-Cl. There was neutrophil infiltration in the post-MCAO brains, and the MPO produced by infiltrating neutrophils might be involved in the taurine to Tau-Cl conversion. Tau-Cl significantly increased the levels of antioxidant enzymes glutamate-cysteine ligase, heme oxygenase-1, NADPH:quinone oxidoreductase 1, and peroxiredoxin-1 in BV2 cells, whereas taurine slightly increased some of them. Antioxidant enzyme levels were increased in the post-MCAO brains, and Tau-Cl further increased the level of MCAO-induced antioxidant enzymes. These results suggest that the neutrophils infiltrate the area of ischemic injury area, where taurine is converted to Tau-Cl, thus protecting from brain injury by scavenging toxic HOCl and increasing antioxidant enzyme expression.

Carveol a Naturally-Derived Potent and Emerging Nrf2 Activator Protects Against Acetaminophen-Induced Hepatotoxicity

Acetaminophen (N-acetyl p-aminophenol or APAP) is used worldwide for its antipyretic and anti-inflammatory potential. However, APAP overdose sometimes causes severe liver damage. In this study, we elucidated the protective effects of carveol in liver injury, using molecular and in silico approaches. Male BALB/c mice were divided into two experimental cohorts, to identify the best dose and to further assess the role of carveol in the nuclear factor E2-related factor; nuclear factor erythroid 2; p45-related factor 2 (Nrf2) pathway. The results demonstrated that carveol significantly modulated the detrimental effects of APAP by boosting endogenous antioxidant mechanisms, such as nuclear translocation of Nrf2 gene, a master regulator of the downstream antioxidant machinery. Furthermore, an inhibitor of Nrf2, called all-trans retinoic acid (ATRA), was used, which exaggerated APAP toxicity, in addition to abrogating the protective effects of carveol; this effect was accompanied by overexpression of inflammatory mediators and liver = 2ltoxicity biomarkers. To further support our notion, we performed virtual docking of carveol with Nrf2-keap1 target, and the resultant drug-protein interactions validated the in vivo findings. Together, our findings suggest that carveol could activate the endogenous master antioxidant Nrf2, which further regulates the expression of downstream antioxidants, eventually ameliorating the APAP-induced inflammation and oxidative stress.

Repurposing FDA Approved Drugs as JNK3 Inhibitor for Prevention of Neuroinflammation Induced by MCAO in Rats

Background

Stress-associated kinases are considered major pathological mediators in several incurable neurological disorders. Importantly, among these stress kinases, the c-Jun NH2-terminal kinase (JNK) has been linked to numerous neuropathological conditions, including oxidative stress, neuroinflammation, and brain degeneration associated with brain injuries such as ischemia/reperfusion injury. In this study, we adopted a drug repurposing/reprofiling approach to explore novel JNK3 inhibitors from FDA-approved medications to supplement existing therapeutic strategies.

Materials and Methods

We performed in silico docking analysis and molecular dynamics simulation to screen potential candidates from the FDA approved drug library using the standard JNK inhibitor SP600125 as a reference. After the virtual screening, dabigatran, estazolam, leucovorin, and pitavastatin were further examined in ischemic stroke using an animal rodent model of focal cerebral ischemia using transient middle cerebral artery occlusion (t-MCAO). The selected drugs were probed for neuroprotective effectiveness by measuring the infarct area (%) and neurological deficits using a 28-point composite score. Biochemical assays including ELISA and immunohistochemical experiments were performed.

Results

We obtained structural insights for dabigatran, estazolam, and pitavastatin binding to JNK3, revealing a significant contribution of the hydrophobic regions and significant residues of active site regions. To validate the docking results, the pharmacological effects of dabigatran, estazolam, leucovorin, and pitavastatin on MCAO were tested in parallel with the JNK inhibitor SP600125. After MCAO surgery, severe neurological deficits were detected in the MCAO group compared with the sham controls, which were significantly reversed by dabigatran, estazolam, and pitavastatin treatment. Aberrant morphological features and brain damage were observed in the ipsilateral cortex and striatum of the MCAO groups. The drugs restored the anti-oxidant enzyme activity and reduced the levels of oxidative stress-induced p-JNK and neuroinflammatory mediators such as NF-kB and TNF-ɑ in rats subjected to MCAO.

Conclusion

Our results demonstrated that the novel FDA-approved medications attenuate ischemic stroke-induced neuronal degeneration, possibly by inhibiting JNK3. Being FDA-approved safe medications, the use of these drugs can be clinically translated for ischemic stroke-associated brain degeneration and other neurodegenerative diseases associated with oxidative stress and neuroinflammation.