The neuroprotective effects of an ethanolic turmeric (Curcuma longa L.) extract against trimethyltin-induced oxidative stress in rats

Evaluation of the protective effect of Curcuma longa and PPARγ agonist, pioglitazone on paraquat-induced lung injury in rats

BACKGROUND

The inhalation of paraquat (PQ), one of the most widely used herbicides in the world, can result in lung injury. Curcuma longa (Cl) has long history in traditional and folk medicine for the treatment of a wide range of disorders including respiratory diseases.

AIM

The aim of the present work was to evaluate the preventive effect of Cl on inhaled PQ-induced lung injury in rats.

METHODS

Male Wistar rats were divided into 8 groups (n = 7), one group exposed to saline (control) and other groups exposed to PQ aerosol. Saline (PQ), Cl extract, (two doses), curcumin (Cu), pioglitazone (Pio), and the combination of Cl-L + Pio and dexamethasone (Dex) were administered during the exposure period to PQ. Total and differential white blood cell (WBC) counts, oxidant and antioxidant indicators in the bronchoalveolar lavage (BALF), interleukin (IL)-10, and tumor necrosis alpha (TNF-α) levels in the lung tissues, lung histologic lesions score, and air way responsiveness to methacholine were evaluated.

RESULTS

WBC counts (Total and differential), malondialdehyde level, tracheal responsiveness (TR), IL-10, TNF-α and histopathological changes of the lung were markedly elevated but total thiol content and the activities of catalase and superoxide dismutase were decreased in the BALF in the PQ group. Both doses of Cl, Cu, Pio, Cl-L + Pio, and Dex markedly improved all measured variables in comparison with the PQ group.

CONCLUSION

CI, Pio, and Cl-L + Pio improved PQ-induced lung inflammation and oxidative damage comparable with the effects of Dex.

Unraveling potential neuroprotective mechanisms of herbal medicine for Alzheimer's diseases through comprehensive molecular docking analyses

Alzheimer's disease (AD) continues to be a worldwide health concern, demanding innovative therapeutic approaches. This study investigates the neuroprotective potential of herbal compounds by scrutinizing their interactions with Beta-Secretase-1 (BACE1). Through comprehensive molecular docking analyses, three compounds, Masticadienonic acid (ΔG: -9.6 kcal/mol), Hederagenin (ΔG: -9.3 kcal/mol), and Anthocyanins (ΔG: -8.1 kcal/mol), emerge as promising BACE1 ligands, displaying low binding energies and strong affinities. ADME parameter predictions, drug-likeness assessments, and toxicity analyses reveal favorable pharmacokinetic profiles for these compounds. Notably, Masticadienonic Acid exhibits optimal drug-likeness (-3.3736) and negligible toxicity concerns. Hederagenin (drug-likeness: -5.3272) and Anthocyanins (drug-likeness: -6.2041) also demonstrate promising safety profiles. Furthermore, pharmacophore modeling elucidates the compounds' unique interaction landscapes within BACE1's active site. Masticadienonic acid showcases seven hydrophobic interactions and a hydrogen bond acceptor interaction with Thr232. Hederagenin exhibits a specific hydrogen bond acceptor interaction with Trp76, emphasizing its selective binding. Anthocyanins reveal a multifaceted engagement, combining hydrophobic contacts and hydrogen bond interactions with key residues. In conclusion, Masticadienonic acid, Hederagenin, and Anthocyanins stand out as promising candidates for further experimental validation, presenting a synergistic balance of efficacy and safety in combating AD through BACE1 inhibition.

The Golden Spice for Life: Turmeric with the Pharmacological Benefits of Curcuminoids Components, Including Curcumin, Bisdemethoxycurcumin, and Demethoxycurcumins

BACKGROUND

Turmeric (Curcuma longa L.), belonging to the Zingiberaceae family, is a perennial rhizomatous plant of tropical and subtropical regions. The three major chemical components responsible for the biological activities of turmeric are curcumin, demethoxycurcumin, and bisdemethoxycurcumin.

METHODS

The literature search included review articles, analytical studies, randomized control experiments, and observations, which have been gathered from various sources, such as Scopus, Google Scholar, PubMed, and ScienceDirect. A review of the literature was carried out using the keywords: turmeric, traditional Chinese medicine, traditional Iranian medicine, traditional Indian medicine, curcumin, curcuminoids, pharmaceutical benefits, turmerone, demethoxycurcumin, and bisdemethoxycurcumin. The main components of the rhizome of the leaf are α-turmerone, β-turmerone, and arturmerone.

RESULTS

The notable health benefits of turmeric are antioxidant activity, gastrointestinal effects, anticancer effects, cardiovascular and antidiabetic effects, antimicrobial activity, photoprotector activity, hepatoprotective and renoprotective effects, and appropriate for the treatment of Alzheimer's disease and inflammatory and edematic disorders.

DISCUSSION

Curcuminoids are phenolic compounds usually used as pigment spices with many health benefits, such as antiviral, antitumour, anti-HIV, anti-inflammatory, antiparasitic, anticancer, and antifungal effects. Curcumin, bisdemethoxycurcumin, and demethoxycurcumin are the major active and stable bioactive constituents of curcuminoids. Curcumin, which is a hydroponic polyphenol, and the main coloring agent in the rhizomes of turmeric, has anti-inflammatory, antioxidant, anti-cancer, and anticarcinogenic activities, as well as beneficial effects for infectious diseases and Alzheimer's disease. Bisdemethoxycurcumin possesses antioxidant, anti-cancer, and anti-metastasis activities. Demethoxycurcumin, which is another major component, has anti-inflammatory, antiproliferative, and anti-cancer activities and is the appropriate candidate for the treatment of Alzheimer's disease.

CONCLUSION

The goal of this review is to highlight the health benefits of turmeric in both traditional and modern pharmaceutical sciences by considering the important roles of curcuminoids and other major chemical constituents of turmeric.

Therapeutic activity of green synthesized selenium nanoparticles from turmeric against cisplatin-induced oxido-inflammatory stress and cell death in mice kidney

Cisplatin (CDDP) is a commonly prescribed chemotherapeutic agent; however, its associated nephrotoxicity limits its clinical efficacy and sometimes requires discontinuation of its use. The existing study was designed to explore the reno-therapeutic efficacy of turmeric (Tur) alone or conjugated with selenium nanoparticles (Tur-SeNPs) against CDDP-mediated renal impairment in mice and the mechanisms underlying this effect. Mice were orally treated with Tur extract (200 mg/kg) or Tur-SeNPs (0.5 mg/kg) for 7 days after administration of a single dose of CDDP (5 mg/kg, i.p.). N-acetyl cysteine NAC (100 mg/kg) was used as a standard antioxidant compound. The results revealed that Tur-SeNPs counteracted CDDP-mediated serious renal effects in treated mice. Compared with the controls, Tur or Tur-SeNPs therapy remarkably decreased the kidney index along with the serum levels of urea, creatinine, Kim-1, and NGAL of the CDDP-injected mice. Furthermore, Tur-SeNPs ameliorated the renal oxidant status of CDDP group demonstrated by decreased MDA and NO levels along with elevated levels of SOD, CAT, GPx, GR, GSH, and gene expression levels of HO-1. Noteworthy, lessening of renal inflammation was exerted by Tur-SeNPs via lessening of IL-6 and TNF-α besides down-regulation of NF-κB gene expression in mouse kidneys. Tur-SeNPs treatment also restored the renal histological features attained by CDDP challenge and hindered renal apoptosis through decreasing the Bax levels and increasing Bcl-2 levels. Altogether, these outcomes suggest that the administration of Tur conjugated with SeNPs is effective neoadjuvant chemotherapy to guard against the renal adverse effects that are associated with CDDP therapy.

The neuroprotective potential of turmeric rhizome and bitter melon on aspartame-induced spatial memory impairment in rats

Aspartame is widely used artificial sweetener. However, chronic exposure to aspartame led to spatial memory impairment and elevated oxidative stress in the brain. Extract of turmeric rhizome (Curcuma longa) (TUR) and extract of bitter melon (Momordica charantia) (BM) is known to have antioxidant activity. The present study was aimed to examine the neuroprotective potential of TUR and BM extracts, either as single or as combination, against the effects of aspartame in the brain. Here, Sprague-Dawley rats fed with aspartame (40 mg/kg BW) for 28 days were compared with rats fed with extract and aspartame. To assess neuroprotective potential, rats were given extract 7 days before and during aspartame treatment. Spatial memory was assessed with Morris water maze test followed with H&E staining of hippocampal region. Brain lipid peroxidation and enzymatic activity of malondialdehyde (MDA), glutathione peroxidase (GPx), and Acetylcholinesterase (AChE) were measured to probe status of oxidative stress in the brain. Aspartame-treated rats demonstrated spatial memory impairment and reduced number of hippocampal cells and elevated levels of MDA, downregulated activity of GPx and elevated activity of AChE. In contrast, animals received both aspartame and extract demonstrated better spatial memory function, higher number of hippocampal areas, increased GPX activity, reduced MDA levels, and decreased AChE activity were observed in the brain of extract-treated rats. Taken together, our results suggest that extract of TUR rhizome and BM fruit exhibit antioxidant activity which may contribute to the neuroprotective effects against aspartame-induced memory impairment in rats.

Design and optimization of a novel herbosomal-loaded PEG-poloxamer topical formulation for the treatment of cold injuries: a quality-by-design approach

The spectrum of cold injuries ranges from frostnip, chilblains to severe frostbite. Cold injuries occur upon prolonged exposure to freezing temperature and are pathologically a combination of ice crystal formation in the tissue resulting in inflammation, thrombosis and ischemia in the extremities, often necessitating limb amputation in extreme cases due to tissue necrosis. Severe forms of frostbite are a cause of major concern to patients as well as the treating physician. Due to the lack of effective treatment modalities and paucity of research on prophylaxis and therapeutics of cold injuries, we developed a novel herbosomal-loaded PEG-poloxamer topical formulation (n-HPTF) employing quality-by-design (QBD) approach. Natural compounds exhibiting potent therapeutic potential for the management of cold injuries were incorporated in novel lipid vesicles (herbosomes) loaded in PEG-poloxamer polymers. The herbosomal formulation effectively creates an occlusion barrier that promotes epithelial regeneration, desmosome scale-up and angiogenesis and thus promotes rapid healing, indicating controlled release of herbosomes. Optimized novel herbosomes showed entrapment efficiency > 90% and < 300 nm mean particle size and in vitro drug permeation of about 2 µg/cm² followed Higuchi's release kinetics. Skin irritancy study on female Sprague-Dawley rats showed no edema or erythema. In vivo bio-efficacy study revealed significant efficacy (p < 0.05) when compared to the standard treatment groups. Graphical abstract presenting the designing and optimization of novel herbosomal-loaded PEG-poloxamer topical formulation (n-HPTF) and predictive model for the in vivo study of the developed n-HPTF on cold injury rat skin model.

Bioactive Compounds and Their Derivatives: An Insight into Prospective Phytotherapeutic Approach against Alzheimer’s Disease

Alzheimer's disease (AD) is a common neurodegenerative brain disorder that causes cellular response alterations, such as impaired cholinergic mechanism, amyloid-beta (Aβ) AD aggregation, neuroinflammation, and several other pathways. AD is still the most prevalent form of dementia and affects many individuals across the globe. The exact cause of the disorder is obscure. There are yet no effective medications for halting, preventing, or curing AD's progress. Plenty of natural products are isolated from several sources and analyzed in preclinical and clinical settings for neuroprotective effects in preventing and treating AD. In addition, natural products and their derivatives have been promising in treating and preventing AD. Natural bioactive compounds play an active modulatory role in the pathological molecular mechanisms of AD development. This review focuses on natural products from plant sources and their derivatives that have demonstrated neuroprotective activities and maybe promising to treat and prevent AD. In addition, this article summarizes the literature pertaining to natural products as agents in the treatment of AD. Rapid metabolism, nonspecific targeting, low solubility, lack of BBB permeability, and limited bioavailability are shortcomings of most bioactive molecules in treating AD. We can use nanotechnology and nanocarriers based on different types of approaches.

A Comprehensive Review on the Therapeutic Potential of Curcuma longa Linn. in Relation to its Major Active Constituent Curcumin

Curcuma longa Linn. (C. longa), popularly known as turmeric, belongs to the Zingiberaceae family and has a long historical background of having healing properties against many diseases. In Unani and Ayurveda medicine, C. longa has been used for liver obstruction and jaundice, and has been applied externally for ulcers and inflammation. Additionally, it is employed in several other ailments such as cough, cold, dental issues, indigestion, skin infections, blood purification, asthma, piles, bronchitis, tumor, wounds, and hepatic disorders, and is used as an antiseptic. Curcumin, a major constituent of C. longa, is well known for its therapeutic potential in numerous disorders. However, there is a lack of literature on the therapeutic potential of C. longa in contrast to curcumin. Hence, the present review aimed to provide in-depth information by highlighting knowledge gaps in traditional and scientific evidence about C. longa in relation to curcumin. The relationship to one another in terms of biological action includes their antioxidant, anti-inflammatory, neuroprotective, anticancer, hepatoprotective, cardioprotective, immunomodulatory, antifertility, antimicrobial, antiallergic, antidermatophytic, and antidepressant properties. Furthermore, in-depth discussion of C. longa on its taxonomic categorization, traditional uses, botanical description, phytochemical ingredients, pharmacology, toxicity, and safety aspects in relation to its major compound curcumin is needed to explore the trends and perspectives for future research. Considering all of the promising evidence to date, there is still a lack of supportive evidence especially from clinical trials on the adjunct use of C. longa and curcumin. This prompts further preclinical and clinical investigations on curcumin.

Melatonin ameliorates trimethyltin chloride-induced cardiotoxicity: The role of nuclear xenobiotic metabolism and Keap1-Nrf2/ARE axis-mediated pyroptosis

Trimethyltin chloride (TMT) is a stabilizer for polyvinyl chloride plastics that causes serious health hazards in nontarget organisms. Melatonin (MT) exhibits powerful protective effects in cardiac diseases. As a new environmental pollutant, TMT-induced cardiotoxicity and the protective effects of MT remain unclear. To explore this, the mice were treated with TMT (2.8 mg/kg) and/or MT (10 mg/kg) for 7 days. Firstly, the histopathological and ultrastructural evaluation showed that TMT induced cardiac damage, tumescent rupture and nuclear pyknosis. Moreover, TMT elevated the expressions of pyroptosis genes NLRP3, ASC and Cas1 and inflammation factors IL-6, IL-17 and TNFα. Secondly, TMT reduced antioxidant enzymes (GSH, CAT and T-AOC) via decreasing the expression of genes associated with the Keap1-Nrf2/ARE pathway to increase oxidative stress. Thirdly, TMT decreased the expression of genes associated with the ARE-driven drug metabolizing enzymes (DMEs), including Akr7a3, Akr1b8, and Akr1b10. Besides, TMT upregulated the mRNA expression of nuclear Xenobiotic metabolism on cytochrome P450s enzymes via increasing the expression of CAR, PXP, and AHR genes. Furthermore, MT treatment mitigated the aforementioned adverse changes induced by TMT. Overall, these results demonstrated that TMT caused pyroptosis and inflammation to aggravate cardiac damage via inducing excessive oxidative stress, imbalance of DMEs homeostasis, and nuclear Xenobiotic metabolism disorder, which could be alleviated by MT.

Beneficial Effects of a Combination of Curcuma longa L. and Citrus junos Against Beta-Amyloid Peptide-Induced Neurodegeneration in Mice

Both Curcuma longa (CL) and Citrus junos Tanaka (CJ) have been used to treat various diseases due to their anti-inflammatory and antioxidative stress activities. In this study, we investigated the ameliorative effect of the combination of CL extract and CJ extract (CCC) against beta-amyloid (Aβ) peptide-induced neurological damage. CCC prevented neurocytotoxicity in vitro. In addition, it was confirmed that abnormal alternation behavior and memory impairment caused by Aβ peptide were reversed by treatment with CCC. Furthermore, CCC treatment led to recovery of the cholinergic system and reactive oxygen species (ROS) oxidative damage defense system. CCC induced expressions of cyclic-adenosine monophosphate response element-binding protein (CREB)-responsive element-binding protein and brain-derived neurotrophic factor were confirmed as was the significantly improved processing in the hippocampus of the mouse Aβ peptides. Accordingly, these results suggest that CCC can prevent and/or reverse neurocytotoxicity and cognitive deficits in a mouse model of Alzheimer's disease.

Evaluation of curcuma and ginger mixture ability to prevent ROS production induced by bisphenol S: an in vitro study

The use of bisphenol S (BPS) as a substitute of Bisphenol A is increasing in several products and it can be found in different environmental and biological matrices. Its toxicity has been studied at different levels and one of BPS toxic mechanisms at high concentrations seems to be the induction of oxidative stress through the generation of reactive oxygen species (ROS). This study evaluates the ability of a curcuma and ginger (CG) mixture to exert an antioxidant effect on rat hepatocytes treated with BPS. The effects of the mixture were compared to those of a well-known antioxidant (Trolox). Three different BPS concentrations were used in order to verify ROS production. 70 µg/mL and 150 µg/mL of BPS generated a significant ROS increase (p < 0.01) as compared to control, while CG mixture was able to decrease this ROS production in hepatic cells, as compared to cells treated with 70 µg/ml of BPS (p < 0.01) restoring control levels. BPS 70 µg/mL was tested for total antioxidant capacity (TEAC), superoxide dismutase (SOD) and total thiols. TEAC and SOD significant decreased (p < 0.05 and p < 0.01, respectively) as compared to controls and CG mixture was able to restore control values. Given the widespread BPS use, results obtained in this study can be of high impact for the community, demonstrating the ability of a mixture of natural products to prevent BPS-induced oxidative stress.

Therapeutic Effects of Hydrogen Gas Inhalation on Trimethyltin-Induced Neurotoxicity and Cognitive Impairment in the C57BL/6 Mice Model

Oxidative stress (OS) is one of the causative factors in the pathogenesis of various neurodegenerative diseases, including Alzheimer’s disease (AD) and cognitive dysfunction. In the present study, we investigated the effects of hydrogen (H₂) gas inhalation in trimethyltin (TMT)-induced neurotoxicity and cognitive dysfunction in the C57BL/6 mice. First, mice were divided into the following groups: mice without TMT injection (NC), TMT-only injection group (TMT only), TMT injection + lithium chloride-treated group as a positive control (PC), and TMT injection + 2% H₂ inhalation-treated group (H₂). The TMT injection groups were administered a single dosage of intraperitoneal TMT injection (2.6 mg/kg body weight) and the H₂ group was treated with 2% H₂ for 30 min once a day for four weeks. Additionally, a behavioral test was performed with Y-maze to test the cognitive abilities of the mice. Furthermore, multiple OS- and AD-related biomarkers such as reactive oxygen species (ROS), nitric oxide (NO), calcium (Ca²⁺), malondialdehyde (MDA), glutathione peroxidase (GPx), catalase, inflammatory cytokines, apolipoprotein E (Apo-E), amyloid β (Aβ)-40, phospho-tau (p-tau), Bcl-2, and Bcl-2- associated X (Bax) were investigated in the blood and brain. Our results demonstrated that TMT exposure alters seizure and spatial recognition memory. However, after H₂ treatment, memory deficits were ameliorated. H₂ treatment also decreased AD-related biomarkers, such as Apo-E, Aβ-40, p-tau, and Bax and OS markers such as ROS, NO, Ca²⁺, and MDA in both serum and brain. In contrast, catalase and GPx activities were significantly increased in the TMT-only group and decreased after H₂ gas treatment in serum and brain. In addition, inflammatory cytokines such as granulocyte colony-stimulating factors (G-CSF), interleukin (IL)-6, and tumor necrosis factor alpha (TNF-α) were found to be significantly decreased after H₂ treatment in both serum and brain lysates. In contrast, Bcl-2 and vascular endothelial growth factor (VEGF) expression levels were found to be enhanced after H₂ treatment. Taken together, our results demonstrated that 2% H₂ gas inhalation in TMT-treated mice exhibits memory enhancing activity and decreases the AD, OS, and inflammatory-related markers. Therefore, H₂ might be a candidate for repairing neurodegenerative diseases with cognitive dysfunction. However, further mechanistic studies are needed to fully clarify the effects of H₂ inhalation on TMT-induced neurotoxicity and cognitive dysfunction.

Defensive potential and deleterious impact of turmeric (Curcuma longa) L rhizome powder supplemented diet on antioxidant status of indomethacin-induced ulcerated wistar rats

Effects of various concentration of turmeric (Curcuma longa [C longa]) rhizome powder (TRP) supplemented diet on the antioxidant status of selected organs (stomach, liver, kidney, and heart) of indomethacin (Indo)-induced ulcerated wistar rats were investigated in this study. The rats were fed with different percentages of TRP supplemented diet (1% [A], 2% [B], 5% [C], and 10% [D]) for 28 days. It was observed from the results that animals fed on 10% turmeric rhizome supplemented and those in the ulcerogenic group had significant reduction in kidney, cardiac gluthione (GSH), superoxide dismutase (SOD), catalase (CAT), and gastric GSH when compared with normal control animals and other pre-treated groups. However, a significant increase was observed in gastric, hepatic, cardiac, and glutathione peroxidase (GPX); kidney and hepatic SOD; cardiac, kidney, hepatic, and gastric CAT of animals pre- treated with TRP supplemented diet (1%-5%) compared with ulcerogenic group. Also, a significant reduction was observed in GPX of animals fed with 10% TRP supplemented diet in comparison with ulcerogenic group. Consumption of TRP in the diet, therefore, should be lesser than 10% of the whole recipe for it to be potent in enhancing antioxidant defensive mechanism of the aforementioned organs and thereby prevent oxidative stress related diseases. It may reduce antioxidant present in those organs which can lead to increase availability of free radical and expose the organs to oxidative stress-related diseases. PRACTICAL APPLICATIONS: Inclusion of turmeric rhizome powder in daily diet has been globally well accepted due to the knowledge of its medicinal values. Nonetheless, the extent at which it should be consumed has been controversial and unclear. Little or no effort has been put in place to educate the populace on the quantity of concentration of C. longa powder which should be in whole recipe or ingredients. Therefore, if turmeric rhizome powder should be included in diet because of its nutritional and medicinal values, this should be with caution and from the results of this study, the concentration should not be up to 100g/kg w/w of the entire recipe.

Toxic Substance-induced Hippocampal Neurodegeneration in Rodents as Model of Alzheimer’s Dementia

BACKGROUND: Alzheimer’s Dementia (AD) cases are increasing with the global elderly population. To study the part of the brain affected by AD, animal models for hippocampal degeneration are still necessary to better understand AD pathogenesis and develop treatment and prevention measures. AIM: This study was a systematic review of toxic substance-induced animal models of AD using the Morris Water Maze method in determining hippocampal-related memory impairment. Our aim was reviewing the methods of AD induction using toxic substances in laboratory rodents and evaluating the report of the AD biomarkers reported in the models. METHODS: Data were obtained from articles in the PubMed database, then compiled, categorized, and analyzed. Eighty studies published in the past 5 years were included for analysis. RESULTS AND DISCUSSION: The most widely used method was intracerebroventricular injection of amyloid-β _substances. However, some less technically challenging techniques using oral or intraperitoneal administration of other toxic substances also produce successful models. Instead of hippocampal neurodegeneration, many studies detected biomarkers of the AD pathological process while some reported inflammation, oxidative stress, neurotrophic factors, and changes of cholinergic activity. Female animals were underrepresented despite a high incidence of AD in women. CONCLUSION: Toxic substances may be used to develop AD animal models characterized with appropriate AD pathological markers. Characterization of methods with the most easy-handling techniques and more studies in female animal models should be encouraged.

Inhibitors of Lipoxygenase and Cyclooxygenase-2 Attenuate Trimethyltin-Induced Neurotoxicity through Regulating Oxidative Stress and Pro-Inflammatory Cytokines in Human Neuroblastoma SH-SY5Y Cells

Trimethyltin (TMT) is an environmental neurotoxin that mediates dopaminergic neuronal injury in the brain. In this study, we characterized the toxic mechanism and possible protective compounds against TMT-induced neurotoxicity in human dopaminergic neuroblastoma SH-SY5Y cells. Antioxidants such as melatonin, N-acetylcysteine (NAC), α-tocopherol, and allopurinol alleviated TMT toxicity. Apoptosis induced by TMT was identified by altered expression of cleaved caspase-3, Bax, Bcl-2, and Bcl-xL through Western blot analysis. The iron chelator deferoxamine ameliorated the alteration of apoptosis-related proteins through TMT exposure. TMT also induced delayed ultrastructural necrotic features such as mitochondrial swelling and cytoplasmic membrane rupture; NAC reduced these necrotic injuries. Esculetin, meloxicam, celecoxib, and phenidone decreased TMT toxicity. Elevation of the pro-inflammatory cytokines IL-1β, TNF-α, and NF-ĸB and reduction of the antioxidant enzymes catalase and glutathione peroxidase-1 (GPx-1) were induced by TMT and ameliorated by inhibitors of LOX and COX-2 enzymes. Both NMDA and non-NMDA antagonists attenuated TMT toxicity. The free calcium ion modulators nimodipine and BAPTA/AM contributed to neuronal survival against TMT toxicity. Inhibitors of the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin pathway, an autophagy regulator, decreased TMT toxicity. These results imply that TMT neurotoxicity is the chief participant in LOX- and COX-2-mediated apoptosis, partly via necrosis and autophagy in SH-SY5Y cells.

Neuroprotective Natural Products for Alzheimer's Disease

Alzheimer's disease (AD) is the number one neurovegetative disease, but its treatment options are relatively few and ineffective. In efforts to discover new strategies for AD therapy, natural products have aroused interest in the research community and in the pharmaceutical industry for their neuroprotective activity, targeting different pathological mechanisms associated with AD. A wide variety of natural products from different origins have been evaluated preclinically and clinically for their neuroprotective mechanisms in preventing and attenuating the multifactorial pathologies of AD. This review mainly focuses on the possible neuroprotective mechanisms from natural products that may be beneficial in AD treatment and the natural product mixtures or extracts from different sources that have demonstrated neuroprotective activity in preclinical and/or clinical studies. It is believed that natural product mixtures or extracts containing multiple bioactive compounds that can work additively or synergistically to exhibit multiple neuroprotective mechanisms might be an effective approach in AD drug discovery.

Experimental and clinical reports on anti-inflammatory, antioxidant, and immunomodulatory effects of Curcuma longa and curcumin, an updated and comprehensive review

Curcuma longa (C. longa) or turmeric is a plant with a long history of use in traditional medicine, especially for treating inflammatory conditions C. longa and its main constituent, curcumin (CUR), showed various pharmacological effects such as antioxidant and anti-microbial properties. The updated knowledge of anti-inflammatory, antioxidant, and immunomodulatory effects of C. longa and CUR is provided in this review article. Pharmacological effects of C. longa, and CUR, including anti-inflammatory, antioxidant, and immunomodulatory properties, were searched using various databases and appropriate keywords until September 2020. Various studies showed anti-inflammatory effects of C. longa and CUR, including decreased white blood cell, neutrophil, and eosinophil numbers, and its protective effects on serum levels of inflammatory mediators such as phospholipase A2 and total protein in different inflammatory disorders. The antioxidant effects of C. longa and CUR were also reported in several studies. The plant extracts and CUR decreased malondialdehyde and nitric oxide levels but increased thiol, superoxide dismutase, and catalase levels in oxidative stress conditions. Treatment with C. longa and CUR also improved immunoglobulin E (Ig)E, pro-inflammatory cytokine interleukin 4 (IL)-4, transforming growth factor-beta, IL-17, interferon-gamma levels, and type 1/type 2 helper cells (Th1)/(Th2) ratio in conditions with disturbance in the immune system. Therefore C. longa and CUR showed anti-inflammatory, antioxidant, and immunomodulatory effects, indicating a potential therapeutic effect of the plant and its constituent, CUR, for treating of inflammatory, oxidative, and immune dysregulation disorders.

An Overview on the Conservative Management of Endometriosis from a Naturopathic Perspective: Phytochemicals and Medicinal Plants

Background: Endometriosis is a chronic and debilitating disease, which affects millions of young women worldwide. Although medicine has incontestably evolved in the last years, there is no common ground regarding the early and accurate diagnosis of this condition, its pathogenic mechanisms, and curative treatment. Even though the spontaneous resolution of endometriosis is sometimes possible, recent reports suggested that it can be a progressive condition. It can associate chronic pelvic pain, vaginal bleeding, infertility, or malignant degenerescence. Conventional treatments could produce many side effects, and despite treatment, the symptoms may reappear. In recent years, experimental evidence suggested that plant-based medicine could exert beneficial effects on endometriosis and endometriosis-related symptoms. This study aims to highlight the pharmaceutical activity of phytochemicals and medicinal plants against endometriosis and to provide a source of information regarding the alternative treatment of this condition. Methods: For this review, we performed a research using PubMed, GoogleScholar, and CrossRef databases. We selected the articles published between January 2000 and July 2020, written in English. Results: We found 17 medicinal plants and 13 phytochemicals, which have demonstrated their beneficial effects against endometriosis. Several of their biological activities consist of antiangiogenic, anti-inflammatory effects, and oxidative-stress reduction. Conclusion: Medicinal herbs and their bioactive compounds exhibit antiangiogenic, antioxidant, sedative and pain-alleviating properties and the effects recorded until now encourage their use for the conservative management of endometriosis.

Neuroprotective Effects of a Novel Inhibitor of c-Jun N-Terminal Kinase in the Rat Model of Transient Focal Cerebral Ischemia

A novel specific inhibitor of c-Jun N-terminal kinase, 11H-indeno[1,2-b]quinoxalin-11-one oxime sodium salt (IQ-1S), has a high affinity to JNK3 compared to JNK1/JNK2. The aim of this work was to study the mechanisms of neuroprotective activity of IQ-1S in the models of reversible focal cerebral ischemia (FCI) in Wistar rats. The animals were administered with an intraperitoneal injection of IQ-1S (5 and 25 mg/kg) or citicoline (500 mg/kg). Administration of IQ-1S exerted a pronounced dose-dependent neuroprotective effect, not inferior to the effects of citicoline. Administration of IQ-1S at doses of 5 and 25 mg/kg reduced the infarct size by 20% and 50%, respectively, 48 h after FCI, whereas administration of citicoline reduced the infarct size by 34%. The administration of IQ-1S was associated with a faster amelioration of neurological status. Control rats showed a 2.0-fold increase in phospho-c-Jun levels in the hippocampus compared to the corresponding values in sham-operated rats 4 h after FCI. Administration of IQ-1S at a dose of 25 mg/kg reduced JNK-dependent phosphorylation of c-Jun by 20%. Our findings suggest that IQ-1S inhibits JNK enzymatic activity in the hippocampus and protects against stroke injury when administered in the therapeutic and prophylactic regimen in the rat model of FCI.

Protective Effects of a New C-Jun N-terminal Kinase Inhibitor in the Model of Global Cerebral Ischemia in Rats

c-Jun N-terminal kinase (JNK) is activated by various brain insults and is implicated in neuronal injury triggered by reperfusion-induced oxidative stress. Some JNK inhibitors demonstrated neuroprotective potential in various models, including cerebral ischemia/reperfusion injury. The objective of the present work was to study the neuroprotective activity of a new specific JNK inhibitor, IQ-1S (11H-indeno[1,2-b]quinoxalin-11-one oxime sodium salt), in the model of global cerebral ischemia (GCI) in rats compared with citicoline (cytidine-5'-diphosphocholine), a drug approved for the treatment of acute ischemic stroke and to search for pleiotropic mechanisms of neuroprotective effects of IQ-1S. The experiments were performed in a rat model of ischemic stroke with three-vessel occlusion (model of 3VO) affecting the brachiocephalic artery, the left subclavian artery, and the left common carotid artery. After 7-min episode of GCI in rats, 25% of animals died, whereas survived animals had severe neurological deficit at days 1, 3, and 5 after GCI. At day 5 after GCI, we observing massive loss of pyramidal neurons in the hippocampal CA1 area, increase in lipid peroxidation products in the brain tissue, and decrease in local cerebral blood flow (LCBF) in the parietal cortex. Moreover, blood hyperviscosity syndrome and endothelial dysfunction were found after GCI. Administration of IQ-1S (intragastrically at a dose 50 mg/kg daily for 5 days) was associated with neuroprotective effect comparable with the effect of citicoline (intraperitoneal at a dose of 500 mg/kg, daily for 5 days).The neuroprotective effect was accompanied by a decrease in the number of animals with severe neurological deficit, an increase in the number of animals with moderate degree of neurological deficit compared with control GCI group, and an increase in the number of unaltered neurons in the hippocampal CA1 area along with a significant decrease in the number of neurons with irreversible morphological damage. In rats with IQ-1S administration, the LCBF was significantly higher (by 60%) compared with that in the GCI control. Treatment with IQ-1S also decreases blood viscosity and endothelial dysfunction. A concentration-dependent decrease (IC50 = 0.8 ± 0.3 μM) of tone in isolated carotid arterial rings constricted with phenylephrine was observed after IQ-1S application in vitro. We also found that IQ-1S decreased the intensity of the lipid peroxidation in the brain tissue in rats with GCI. 2.2-Diphenyl-1-picrylhydrazyl scavenging for IQ-1S in acetonitrile and acetone exceeded the corresponding values for ionol, a known antioxidant. Overall, these results suggest that the neuroprotective properties of IQ-1S may be mediated by improvement of cerebral microcirculation due to the enhanced vasorelaxation, beneficial effects on blood viscosity, attenuation of the endothelial dysfunction, and antioxidant/antiradical IQ-1S activity.

Plant-derived medicines for treatment of endometriosis: A comprehensive review of molecular mechanisms

Endometriosis is an estrogen-dependent disease with inflammatory lesions at extra-uterine sites, causing pelvic pain and fertility reduction. Conventional therapies primarily focus on reducing systemic levels of estrogens; however, they do not have desirable effectiveness and possess considerable side effects. Therefore, there is a growing interest in the use of herbal medicine for the treatment of endometriosis. In this paper, electronic databases including PubMed, Scopus, Cochrane library and Google Scholar were searched to obtain any studies evaluating any herbal products in the management of endometriosis. Data were collected from 1980 to 2018. Most of studies investigating the effect of herbal medicines in endometriosis were in vitro and animal and only three clinical trials were found; one on Pinus pinaster bark extract (Pycnogenol) and two on Chinese herbal formulas. The studies on phytochemicals had mostly focused on polyphenolic compounds (epigallocatechin-3-gallate, genistein) and sesquiterpenes (β-caryophyllene, parthenolide). Various molecular mechanisms of action have been involved in beneficial effects of herbal medicines and phytochemicals including anti-inflammatory (via reduction of proinflammatory cytokines such as interleukin -1, interleukin -6, interleukin -8, transforming growth factor-beta, tumor necrosis factor-α, nuclear factor-kappa B, growth factors, monocyte chemoattractant protein-1), antioxidant (through downregulation of hydrogen peroxide, malondialdehyde, reactive oxygen species and upregulation of superoxide dismutase), anti-proliferative and apoptotic (via enhancing Bcl-2-associated X protein/ B-cell lymphoma-2 and caspase3, 8 and 9 activity), anti-angiogenic (by downregulation of vascular endothelial growth factor receptors/ vascular endothelial growth factor), anti-invasive (via decreasing expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1 and matrix metalloproteinases), immunomodulatory, and estrogen modulating activities. So, medicinal plants seem to be a valuable source for identifying new drugs for treatment of endometriosis; however, since most of studies are preclinical, further clinical trials are required to achieve more conclusive results.

Momordica charantia Ethanol Extract Attenuates H₂O₂-Induced Cell Death by Its Antioxidant and Anti-Apoptotic Properties in Human Neuroblastoma SK-N-MC Cells

Oxidative stress, which is induced by reactive oxygen species (ROS), causes cellular damage which contributes to the pathogenesis of neurodegenerative diseases. Momordica charantia (MC), a traditional medicinal plant, is known to have a variety of health benefits, such as antidiabetic, anti-inflammatory, and antioxidant effects. However, it is unknown whether MC has protective effects against oxidative stress-induced neuronal cell death. The aim of this study was to investigate the potential action of MC on oxidative stress induced by H₂O₂. First, we tested whether the pretreatment of Momordica charantia ethanol extract (MCEE) attenuates H₂O₂-induced cell death in human neuroblastoma SK-N-MC cells. MCEE pretreatment significantly improved cell viability and apoptosis that deteriorated by H₂O₂. Further, MCEE ameliorated the imbalance between intracellular ROS production and removal through the enhancement of the intracellular antioxidant system. Intriguingly, the inhibition of apoptosis was followed by the blockage of mitochondria-dependent cell death cascades and suppression of the phosphorylation of the mitogen-activated protein kinase signaling (MAPKs) pathway by MCEE. Taken together, MCEE was shown to be effective in protecting against H₂O₂-induced cell death through its antioxidant and anti-apoptotic properties.