Curcumin modulates cell death and is protective in Huntington's disease model

Neuroprotective Potential of Eugenol in Polyglutamine-Mediated Neurodegenerative Disease Using Transgenic Drosophila Model

Polyglutamine (PolyQ) diseases including Huntington's disease are devastating neurodegenerative disorders characterized by progressive neuronal loss and motor dysfunction. PolyQ pathology involves multiple cellular events and phytochemicals with multi-target mechanisms hold promise to treat these diseases with least side effects. One such promising phytochemical is Eugenol, which possesses antioxidant and anti-inflammatory properties, potentially targeting disrupted cellular pathways in PolyQ diseases. The present study investigated the effects of Eugenol on neurodegeneration and motor dysfunction in transgenic Drosophila models of PolyQ diseases. In this study, the robust pseudopupil assay was performed to analyze adult photoreceptor neuron degeneration, a marker of widespread degenerative events. Furthermore, the well-established crawling and climbing assays were conducted to evaluate progressive motor dysfunction in the PolyQ larvae and flies. This study found that Eugenol administration at disease onset or after progression reduced PolyQ disease phenotypes, particularly, neurodegeneration and motor dysfunction in a dose-dependent manner and with no side effects. Thus, this study suggests that Eugenol could be a viable candidate for developing treatments for PolyQ diseases, offering a multi-target approach with the potential for minimal or no side effects compared to conventional therapies.

Curcuma Longa: Nutraceutical Use and Association With Nanotechnology

Curcumin is a natural product found in the rhizome of Curcuma longa (L.) and other Curcuma spp. As a lipophilic molecule, it has greater affinity for polar, non-polar, alkaline, or extremely acidic organic solvents. Several studies indicate that curcumin has several benefits for human health, for example, against degenerative diseases, cancer, and infectious diseases. To obtain a quality product with nutraceutical properties, it is necessary to know its physicochemical characteristics and preserve it from cultivation until ingestion by the human. However, its low solubility leads to low absorption; in this context, nanotechnological systems can contribute to increase curcumin bioavailability. This review aims to highlight important issues in all stages that curcumin goes through: from aspects related to its extraction to its association with nanotechnology. Although curcumin extraction process is already well established, it is possible to observe more and more research focused on increasing yield and being more environmentally friendly. Further, curcumin's low absorption is notable due to its physicochemical characteristics, mainly due to its low aqueous solubility. However, its association with nanotechnology shows to be promising and an increasingly growing trend because the use of this "Indian solid gold" is the hope of many patients.

Polyphenols: Secondary Metabolites with a Biological Impression

Polyphenols are natural compounds which are plant-based bioactive molecules, and have been the subject of growing interest in recent years. Characterized by multiple varieties, polyphenols are mostly found in fruits and vegetables. Currently, many diseases are waiting for a cure or a solution to reduce their symptoms. However, drug or other chemical strategies have limitations for using a treatment agent or still detection tool of many diseases, and thus researchers still need to investigate preventive or improving treatment. Therefore, it is of interest to elucidate polyphenols, their bioactivity effects, supplementation, and consumption. The disadvantage of polyphenols is that they have a limited bioavailability, although they have multiple beneficial outcomes with their bioactive roles. In this context, several different strategies have been developed to improve bioavailability, particularly liposomal and nanoparticles. As nutrition is one of the most important factors in improving health, the inclusion of plant-based molecules in the daily diet is significant and continues to be enthusiastically researched. Nutrition, which is important for individuals of all ages, is the key to the bioactivity of polyphenols.

Medicinal herbal remedies in neurodegenerative diseases: an update on antioxidant potential

It has been widely documented that medicinal herbal remedies are effective, have fewer side effects than conventional medicine, and have a synergistic effect on health collaborations in the fight against complicated diseases. Traditional treatments for neurological problems in ancient times sometimes involved the use of herbal remedies and conventional methods from East Asian countries including India, Japan, China, and Korea. We collected and reviewed studies on plant-derived neuroprotective drugs and tested them in neurotoxic models. Basic research, preclinical and clinical transgene research can benefit from in silico, in vitro, and in vivo investigations. Research, summaries of the extracts, fractions, and herbal ingredients were compiled from popular scientific databases, which were then examined according to origin and bioactivity. Given the complex and varied causes of neurodegeneration, it may be beneficial to focus on multiple mechanisms of action and a neuroprotection approach. This approach aims to prevent cell death and restore function to damaged neurons, offering promising strategies for preventing and treating neurodegenerative diseases. Neurodegenerative illnesses can potentially be treated with natural compounds that have been identified as neuroprotective agents. To gain deeper insights into the neuropharmacological mechanisms underlying the neuroprotective and therapeutic properties of naturally occurring antioxidant phytochemical compounds in diverse neurodegenerative diseases, this study aims to comprehensively review such compounds, focusing on their modulation of apoptotic markers such as caspase, Bax, Bcl-2, and proinflammatory markers. In addition, we delve into a range of efficacies of antioxidant phytochemical compounds as neuroprotective agents in animal models. They reduce the oxidative stress of the brain and have been shown to have anti-apoptotic effects. Many researches have demonstrated that plant extracts or bioactive compounds can fight neurodegenerative disorders. Herbal medications may offer neurodegenerative disease patients' new treatments. This may be a cheaper and more culturally appropriate alternative to standard drugs for millions of people with age-related NDDs.

Huntington's Disease: Complex Pathogenesis and Therapeutic Strategies

Huntington's disease (HD) arises from the abnormal expansion of CAG repeats in the huntingtin gene (HTT), resulting in the production of the mutant huntingtin protein (mHTT) with a polyglutamine stretch in its N-terminus. The pathogenic mechanisms underlying HD are complex and not yet fully elucidated. However, mHTT forms aggregates and accumulates abnormally in neuronal nuclei and processes, leading to disruptions in multiple cellular functions. Although there is currently no effective curative treatment for HD, significant progress has been made in developing various therapeutic strategies to treat HD. In addition to drugs targeting the neuronal toxicity of mHTT, gene therapy approaches that aim to reduce the expression of the mutant HTT gene hold great promise for effective HD therapy. This review provides an overview of current HD treatments, discusses different therapeutic strategies, and aims to facilitate future therapeutic advancements in the field.

Curcumin, inflammation, and neurological disorders: How are they linked?

Background

Despite the extensive research in recent years, the current treatment modalities for neurological disorders are suboptimal. Curcumin, a polyphenol found in Curcuma genus, has been shown to mitigate the pathophysiology and clinical sequalae involved in neuroinflammation and neurodegenerative diseases.

Methods

We searched PubMed database for relevant publications on curcumin and its uses in treating neurological diseases. We also reviewed relevant clinical trials which appeared on searching PubMed database using 'Curcumin and clinical trials'.

Results

This review details the pleiotropic immunomodulatory functions and neuroprotective properties of curcumin, its derivatives and formulations in various preclinical and clinical investigations. The effects of curcumin on neurodegenerative diseases such as Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), brain tumors, epilepsy, Huntington's disorder (HD), ischemia, Parkinson's disease (PD), multiple sclerosis (MS), and traumatic brain injury (TBI) with a major focus on associated signalling pathways have been thoroughly discussed.

Conclusion

This review demonstrates curcumin can suppress spinal neuroinflammation by modulating diverse astroglia mediated cascades, ensuring the treatment of neurological disorders.

Underlying Mechanisms of Brain Aging and Neurodegenerative Diseases as Potential Targets for Preventive or Therapeutic Strategies Using Phytochemicals

During aging, several tissues and biological systems undergo a progressive decline in function, leading to age-associated diseases such as neurodegenerative, inflammatory, metabolic, and cardiovascular diseases and cancer. In this review, we focus on the molecular underpinning of senescence and neurodegeneration related to age-associated brain diseases, in particular, Alzheimer's and Parkinson's diseases, along with introducing nutrients or phytochemicals that modulate age-associated molecular dysfunctions, potentially offering preventive or therapeutic benefits. Based on current knowledge, the dysregulation of microglia genes and neuroinflammation, telomere attrition, neuronal stem cell degradation, vascular system dysfunction, reactive oxygen species, loss of chromosome X inactivation in females, and gut microbiome dysbiosis have been seen to play pivotal roles in neurodegeneration in an interactive manner. There are several phytochemicals (e.g., curcumin, EGCG, fucoidan, galangin, astin C, apigenin, resveratrol, phytic acid, acacetin, daucosterol, silibinin, sulforaphane, withaferin A, and betulinic acid) that modulate the dysfunction of one or several key genes (e.g., TREM2, C3, C3aR1, TNFA, NF-kb, TGFB1&2, SIRT1&6, HMGB1, and STING) affected in the aged brain. Although phytochemicals have shown promise in slowing down the progression of age-related brain diseases, more studies to identify their efficacy, alone or in combinations, in preclinical systems can help to design novel nutritional strategies for the management of neurodegenerative diseases in humans.

Curcumin-loaded cockle shell-derived calcium carbonate nanoparticles ameliorates lead-induced neurotoxicity in rats via attenuation of oxidative stress

A substantial global health burden is associated with neurotoxicity caused by lead (Pb) exposure and the common mechanism of this toxicity is mainly via oxidative damage. Curcumin has remarkable pharmacological activities but remains clinically constrained due to its poor bioavailability when orally administered. Currently, cockle shell-derived calcium carbonate nanoparticle (CSCaCO3NP) is gaining more acceptance in nanomedicine as a nanocarrier to various therapeutics. This study aimed at investigating the ameliorative effect of curcumin-loaded CSCaCO3NP (Cur-CSCaCO3NP) on lead-induced neurotoxicity in rats. A total of 36 male Sprague-Dawley rats were randomly assigned into five groups. Each group consists of 6 rats apart from the control group which consists of 12 rats. During the 4 weeks induction phase, all rats received a flat dose of 50 mg/kg of lead while the control group received normal saline. The treatment phase lasted for 4 weeks, and all rats received various doses of treatments as follows: group C (Cur 100) received 100 mg/kg of curcumin, group D (Cur-CSCaCO3NP 50) received 50 mg/kg of Cur-CSCaCO3NP, and group E (Cur-CSCaCO3NP 100) received 100 mg/kg of Cur-CSCaCO3NP. The motor function test was carried out using the horizontal bar method. The cerebral and cerebellar oxidative biomarker levels were estimated using ELISA and enzyme assay kits. Lead-administered rats revealed a significant decrease in motor scores and SOD activities with a resultant increase in MDA levels. Furthermore, marked cellular death of the cerebral and cerebellar cortex was observed. Conversely, treatment with Cur-CSCaCO3NP demonstrated enhanced ameliorative effects when compared with free curcumin treatment by significantly reversing the aforementioned alterations caused by lead. Thus, CSCaCO3NP enhanced the efficacy of curcumin by ameliorating the lead-induced neurotoxicity via enhanced attenuation of oxidative stress.

Cell Rearrangement and Oxidant/Antioxidant Imbalance in Huntington's Disease

Huntington's Disease (HD) is a hereditary neurodegenerative disorder caused by the expansion of a CAG triplet repeat in the HTT gene, resulting in the production of an aberrant huntingtin (Htt) protein. The mutant protein accumulation is responsible for neuronal dysfunction and cell death. This is due to the involvement of oxidative damage, excitotoxicity, inflammation, and mitochondrial impairment. Neurons naturally adapt to bioenergetic alteration and oxidative stress in physiological conditions. However, this dynamic system is compromised when a neurodegenerative disorder occurs, resulting in changes in metabolism, alteration in calcium signaling, and impaired substrates transport. Thus, the aim of this review is to provide an overview of the cell's answer to the stress induced by HD, focusing on the role of oxidative stress and its balance with the antioxidant system.

Application of nanomaterials in the treatment of intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is a non-traumatic hemorrhage caused by the rupture of blood vessels in the brain parenchyma, with an acute mortality rate of 30%‒40%. Currently, available treatment options that include surgery are not promising, and new approaches are urgently needed. Nanotechnology offers new prospects in ICH because of its unique benefits. In this review, we summarize the applications of various nanomaterials in ICH. Nanomaterials not only enhance the therapeutic effects of drugs as delivery carriers but also contribute to several facets after ICH such as repressing detrimental neuroinflammation, resisting oxidative stress, reducing cell death, and improving functional deficits.

Amendment of Altered Immune Response by Curcumin in Drosophila Model of Huntington's Disease

BACKGROUND

Though primarily classified as a brain disorder, surplus studies direct Huntington's disease (HD) to be a multi-system disorder affecting various tissues and organs, thus affecting overall physiology of host. Recently, we have reported that neuronal expression of mutant huntingtin induces immune dysregulation in Drosophila and may pose chronic threat to challenged individuals. Therefore, we tested the polyphenolic compound curcumin to circumvent the impact of immune dysregulation in Drosophila model of HD.

OBJECTIVE

The present study examined the molecular basis underlying immune derangements and immunomodulatory potential of curcumin in HD.

METHODS

UAS-GAL4 system was used to imitate the HD symptoms in Drosophila, and the desired female progenies (elav > Httex1pQ25; control and elav > Httex1pQ93; diseased) were cultured on food mixed without and with 10 μM concentration of curcumin since early development. Effect of curcumin supplementation was investigated by monitoring the hemocytes' count and their functional abilities in diseased condition. Reactive oxygen species (ROS) level in cells was assessed by DHE staining and mitochondrial dysfunction was assessed by CMXros red dye. In addition, transcript levels of pro-inflammatory cytokines and anti-microbial peptides were monitored by qRT-PCR.

RESULTS

We found that curcumin supplementation commendably reduced higher crystal cell count and phenoloxidase activity in diseased flies. Interestingly, curcumin significantly managed altered plasmatocytes count, improved their phagocytic activity by upregulating the expression of key phagocytic receptors in HD condition. Moreover, substantial alleviation of ROS levels and mitochondria dysfunction was observed in plasmatocytes of diseased flies upon curcumin supplementation. Furthermore, curcumin administration effectively attenuated transcriptional expression of pro-inflammatory cytokines and AMPs in diseased flies.

CONCLUSIONS

Our results indicate that curcumin efficiently attenuates immune derangements in HD flies and may prove beneficial in alleviating complexities associated with HD.

In silico study on spice-derived antiviral phytochemicals against SARS-CoV-2 TMPRSS2 target

Corona Virus Disease (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a pandemic that has claimed so far over half a million human life across the globe. Researchers all over the world are exploring various molecules including phytochemicals to get a potential anti-COVID-19 drug. Certain phytochemicals present in some spices are claimed to possess antiviral, anti-bacterial, and anti-fungal properties. Hence, an in-silico study was done by selecting eighteen well reported antiviral phytochemicals from some spices commonly used in Indian kitchen viz. Curcuma longa (Turmeric), Nigella sativa (Black cumin), Piper nigrum (Black pepper), Trachyspermum ammi (Carom) and Zingiber officinale (Ginger) to find out whether they can prevent SARS-CoV-2 infection. Firstly, we predicted the structure of TMPRSS2 (transmembrane protease serine 2), a host protein that truncates spike protein of SARS-CoV-2 thereby facilitating its endocytosis, and then docked against its catalytic domain the selected phytochemicals and camostat (a well-known synthetic inhibitor of TMPRSS2). Thereafter, stability of seven best docked phytochemicals and camostat were scrutinized by Molecular Dynamic Simulation (MDS). MDS analysis indicated bisdemethoxycurcumin (BDMC), carvacrol and thymol as better inhibitors than the camostat due to their stable binding with TMPRSS2 in its oxyanion hole and inducing subtle modification in the spatial arrangement of the catalytic triad residues. Among these three phytochemicals, carvacrol appeared to be the best inhibitor, followed by BDMC, whereas thymol was least effective.

Multifaceted role of polyphenols in the treatment and management of neurodegenerative diseases

Neurodegenerative diseases (NDDs) are conditions that cause neuron structure and/or function to deteriorate over time. Genetic alterations may be responsible for several NDDs. However, a multitude of physiological systems can trigger neurodegeneration. Several NDDs, such as Huntington's, Parkinson's, and Alzheimer's, are assigned to oxidative stress (OS). Low concentrations of reactive oxygen and nitrogen species are crucial for maintaining normal brain activities, as their increasing concentrations can promote neural apoptosis. OS-mediated neurodegeneration has been linked to several factors, including notable dysfunction of mitochondria, excitotoxicity, and Ca²⁺ stress. However, synthetic drugs are commonly utilized to treat most NDDs, and these treatments have been known to have side effects during treatment. According to providing empirical evidence, studies have discovered many occurring natural components in plants used to treat NDDs. Polyphenols are often safer and have lesser side effects. As, epigallocatechin-3-gallate, resveratrol, curcumin, quercetin, celastrol, berberine, genistein, and luteolin have p-values less than 0.05, so they are typically considered to be statistically significant. These polyphenols could be a choice of interest as therapeutics for NDDs. This review highlighted to discusses the putative effectiveness of polyphenols against the most prevalent NDDs.

Pathogenesis of Huntington's Disease: An Emphasis on Molecular Pathways and Prevention by Natural Remedies

BACKGROUND

Huntington's disease is an inherited autosomal dominant trait neuro-degenerative disorder caused by changes (mutations) of a gene called huntingtin (htt) that is located on the short arm (p) of chromosome 4, CAG expansion mutation. It is characterized by unusual movements, cognitive and psychiatric disorders.

OBJECTIVE

This review was undertaken to apprehend biological pathways of Huntington's disease (HD) pathogenesis and its management by nature-derived products. Natural products can be lucrative for the management of HD as it shows protection against HD in pre-clinical trials. Advanced research is still required to assess the therapeutic effectiveness of the known organic products and their isolated compounds in HD experimental models.

SUMMARY

Degeneration of neurons in Huntington's disease is distinguished by progressive loss of motor coordination and muscle function. This is due to the expansion of CAG trinucleotide in the first exon of the htt gene responsible for neuronal death and neuronal network degeneration in the brain. It is believed that the factors such as molecular genetics, oxidative stress, excitotoxicity, mitochondrial dysfunction, neuroglia dysfunction, protein aggregation, and altered UPS leads to HD. The defensive effect of the natural product provides therapeutic efficacy against HD. Recent reports on natural drugs have enlightened the protective role against HD via antioxidant, anti-inflammatory, antiapoptotic, and neurofunctional regulation.

Ameliorating potential of curcumin and its analogue in central nervous system disorders and related conditions: A review of molecular pathways

Curcumin, isolated from turmeric (Curcuma longa L.) is one of the broadly studied phytomolecule owing to its strong antioxidant and anti-inflammatory potential and has been considered a promising therapeutic candidate in a wide range of disorders. Considering, its low bioavailability, different curcumin analogs have been developed to afford desired pharmacokinetic profile and therapeutic outcome in varied pathological states. Several preclinical and clinical studies have indicated that curcumin ameliorates mitochondrial dysfunction, inflammation, oxidative stress apoptosis-mediated neural cell degeneration and could effectively be utilized in the treatment of different neurodegenerative diseases. Hence, in this review, we have summarized key findings of experimental and clinical studies conducted on curcumin and its analogues with special emphasis on molecular pathways, viz. NF-kB, Nrf2-ARE, glial activation, apoptosis, angiogenesis, SOCS/JAK/STAT, PI3K/Akt, ERK1/2 /MyD88 /p38 MAPK, JNK, iNOS/NO, and MMP pathways involved in imparting ameliorative effects in the therapy of neurodegenerative disorders and associated conditions.

Emerging Promise of Phytochemicals in Ameliorating Neurological Disorders

BACKGROUND

The field of medicine and synthetic drug development have advanced rapidly over the past few decades. However, research on alternative medicine such as phytochemicals cannot be ignored. The main reason for prominent curiosity about phytochemicals stems from the belief that usage of natural compounds is safer and has lesser detrimental side effects.

OBJECTIVE

The aim of the present review was to discuss in detail with several phytochemicals that have been studied or are being studied in the context of various neurological disorders including depression, Alzheimer's disease, Huntington's disease and even neuroinflammatory disorders such as encephalitis.

METHODS

The potential role of phytochemicals in the treatment or management of symptoms associated with neurological disorders have been included in this article. All data included in this paper has been pooled from various databases including Google Scholar, PubMed, Science Direct, Springer and Wiley Online Library.

RESULTS

Phytochemicals have been widely studied for their therapeutic properties associated with neurological disorders. Using various experimental techniques for both in vivo and in vitro experiments, studies have shown that phytochemicals do have antioxidant, anti-inflammatory and neuroprotective activities which play major roles in the treatment of neurological diseases.

CONCLUSION

Even though there has been compelling evidence of the therapeutic role of phytochemicals, further research is still required to evaluate the safety and efficacy of these medicines. Using previously published papers as foundation for additional research such as preclinical studies and clinical trials, phytochemicals can become a safer alternative to synthetic drugs for treating a spectrum of neurological diseases.

Curcumin as a Holistic Treatment for Tau Pathology

Global forecasts for prevalence of Alzheimer’s Disease (AD) estimate that 152.8 million people will have dementia in 2050, a sharp rise from 57.4 million in 2019 (GBD 2019). This rise can be attributable to increases in population growth and aging, but in the absence of disease-modifying therapies it poses a huge societal challenge that must be addressed urgently. One way to combat this challenge is to explore the utility of holistic treatments that may protect against AD, including traditional herbs, spices and other nutraceuticals that are pharmacologically safe, inexpensive and readily available. In this light, the spice turmeric, and its active ingredient curcumin, has been investigated as a potential holistic treatment for AD over the past 2 decades; however, promising results with animal studies have not translated to success in clinical trials. One issue is that most animal models examining the effects of curcumin and curcumin derivatives in AD have been done with a focus at ameliorating amyloid pathology. Due to the limited success of Amyloid-β-based drugs in recent clinical trials, tau-focused therapeutics provide a promising alternative. In this article, we aim to provide a clearer picture of what is currently known about the effectiveness of curcumin and curcumin derivatives to ameliorate tau pathology. Tau focused studies may help inform more successful clinical studies by placing greater emphasis on the development and optimised delivery of curcumin derivatives that more effectively target tau pathology.

A review on Huntington protein Insight into protein aggregation and therapeutic interventions

Huntington disease (HD) is a distressing, innate neurodegenerative disease that descends from CAG repeat expansion in the huntingtin gene causing behavioral changes, motor dysfunction, and dementia in children and adults. Mutation in huntingtin (HTT) protein has been suggested to cause neuron loss in the cortex and striatum through various mechanisms including abnormal regulation of transcription, proteasomal dysfunction, post-translational modification, and other events, regulating toxicity. Pathogenesis of HD involves cleavage of the huntingtin protein followed by the neuronal accumulation of its aggregated form. Several research groups made possible efforts to reduce huntingtin gene expression, protein accumulation, and protein aggregation using inhibitors and molecular chaperones as developing drugs against HD. Herein, we review the mechanism proposed towards the formation of HTT protein aggregation and the impact of therapeutic strategies for the treatment of HD.

The Functional Roles of Curcumin on Astrocytes in Neurodegenerative Diseases

Progressive abnormality and loss of axons and neurons in the central nervous system (CNS) cause neurodegenerative diseases (NDs). Protein misfolding and its collection are the most important pathological features of NDs. Astrocytes are the most plentiful cells in the mammalian CNS (about 20-40% of the human brain) and have several central functions in the maintenance of the health and correct function of the CNS. Astrocytes have an essential role in the preservation of brain homeostasis, and it is not surprising that these multifunctional cells have been implicated in the onset and progression of several NDs. Thus, they become an exciting target for the study of NDs. Over almost 15 years, it was revealed that curcumin has several therapeutic effects in a wide variety of diseases' treatment. Curcumin is a valuable ingredient present in turmeric spice and has several essential roles, including those which are anticarcinogenic, hepatoprotective, thrombosuppressive, cardioprotective, anti-arthritic, anti-inflammatory, antioxidant, chemopreventive, chemotherapeutic, and anti-infectious. Furthermore, curcumin can suppress inflammation; promote angiogenesis; and treat diabetes, pulmonary problems, and neurological dysfunction. Here, we review the effects of curcumin on astrocytes in NDs, with a focus on Alzheimer's disease, Parkinson's disease, multiple scleroses, Huntington's disease, and amyotrophic lateral sclerosis.

Amyotrophic Lateral Sclerosis: A Diet Review

Amyotrophic lateral sclerosis (ALS) is a fatal disease related to upper and lower motor neurons degeneration. Although the environmental and genetic causes of this disease are still unclear, some factors involved in ALS onset such as oxidative stress may be influenced by diet. A higher risk of ALS has been correlated with a high fat and glutamate intake and β-methylamino-L-alanine. On the contrary, a diet based on antioxidant and anti-inflammatory compounds, such as curcumin, creatine, coenzyme Q10, vitamin E, vitamin A, vitamin C, and phytochemicals could reduce the risk of ALS. However, data are controversial as there is a discrepancy among different studies due to a limited number of samples and the many variables that are involved. In addition, an improper diet could lead to an altered microbiota and consequently to an altered metabolism that could predispose to the ALS onset. In this review we summarized some research that involve aspects related to ALS such as the epidemiology, the diet, the eating behaviour, the microbiota, and the metabolic diseases. Further research is needed to better comprehend the role of diet and the metabolic diseases in the mechanisms leading to ALS onset and progression.

Management of altered metabolic activity in Drosophila model of Huntington's disease by curcumin

Huntington's disease (HD) is a devastating polyglutamine disorder characterized by extensive neurodegeneration and metabolic abnormalities at systemic, cellular and intracellular levels. Metabolic alterations in HD manifest as abnormal body weight, dysregulated biomolecule levels, impaired adipocyte functions, and defective energy state which exacerbate disease progression and pose acute threat to the health of challenged individuals in form of insulin resistance, cardiovascular disease, and energy crisis. To colossally mitigate disease symptoms, we tested the efficacy of curcumin in Drosophila model of HD. Curcumin is the bioactive component of turmeric (Curcuma longa Linn), well-known for its ability to modulate metabolic activities. We found that curcumin effectively managed abnormal body weight, dysregulated lipid content, and carbohydrate level in HD flies. In addition, curcumin administration lowered elevated reactive-oxygen-species levels in adult adipose tissue of diseased flies, and improved survival and locomotor function in HD flies at advanced disease stage. Altogether, these findings clearly suggest that curcumin efficiently attenuates metabolic derangements in HD flies and can prove beneficial in alleviating the complexities associated with HD.

Curcumin and Nano-Curcumin Mitigate Copper Neurotoxicity by Modulating Oxidative Stress, Inflammation, and Akt/GSK-3β Signaling

Copper (Cu) is essential for multiple biochemical processes, and copper sulphate (CuSO₄) is a pesticide used for repelling pests. Accidental or intentional intoxication can induce multiorgan toxicity and could be fatal. Curcumin (CUR) is a potent antioxidant, but its poor systemic bioavailability is the main drawback in its therapeutic uses. This study investigated the protective effect of CUR and N-CUR on CuSO₄-induced cerebral oxidative stress, inflammation, and apoptosis in rats, pointing to the possible involvement of Akt/GSK-3β. Rats received 100 mg/kg CuSO₄ and were concurrently treated with CUR or N-CUR for 7 days. Cu-administered rats exhibited a remarkable increase in cerebral malondialdehyde (MDA), NF-κB p65, TNF-α, and IL-6 associated with decreased GSH, SOD, and catalase. Cu provoked DNA fragmentation, upregulated BAX, caspase-3, and p53, and decreased BCL-2 in the brain of rats. N-CUR and CUR ameliorated MDA, NF-κB p65, and pro-inflammatory cytokines, downregulated pro-apoptotic genes, upregulated BCL-2, and enhanced antioxidants and DNA integrity. In addition, both N-CUR and CUR increased AKT Ser473 and GSK-3β Ser9 phosphorylation in the brain of Cu-administered rats. In conclusion, N-CUR and CUR prevent Cu neurotoxicity by attenuating oxidative injury, inflammatory response, and apoptosis and upregulating AKT/GSK-3β signaling. The neuroprotective effect of N-CUR was more potent than CUR.

Oxidative Stress and Neurodegeneration: Interconnected Processes in PolyQ Diseases

Neurodegenerative polyglutamine (polyQ) disorders are caused by trinucleotide repeat expansions within the coding region of disease-causing genes. PolyQ-expanded proteins undergo conformational changes leading to the formation of protein inclusions which are associated with selective neuronal degeneration. Several lines of evidence indicate that these mutant proteins are associated with oxidative stress, proteasome impairment and microglia activation. These events may correlate with the induction of inflammation in the nervous system and disease progression. Here, we review the effect of polyQ-induced oxidative stress in cellular and animal models of polyQ diseases. Furthermore, we discuss the interplay between oxidative stress, neurodegeneration and neuroinflammation using as an example the well-known neuroinflammatory disease, Multiple Sclerosis. Finally, we review some of the pharmaceutical interventions which may delay the onset and progression of polyQ disorders by targeting disease-associated mechanisms.

Curcumin: A small molecule with big functionality against amyloid aggregation in neurodegenerative diseases and type 2 diabetes

Amyloidosis is a concept that implicates disorders and complications that are due to abnormal protein accumulation in different cells and tissues. Protein aggregation-associated diseases are classified according to the type of aggregates and deposition sites, such as neurodegenerative disorders and type 2 diabetes mellitus. Polyphenolic phytochemicals such as curcumin and its derivatives have anti-amyloid effects both in vitro and in animal models; however, the underlying mechanisms are not understood. In this review, we summarized possible mechanisms by which curcumin could interfere with self-assembly processes and reduce amyloid aggregation in amyloidosis. Furthermore, we discuss clinical trials in which curcumin is used as a therapeutic agent for the treatment of diseases linking to protein aggregates.

Dietary nutrition for neurological disease therapy: Current status and future directions

Adequate food intake and relative abundance of dietary nutrients have undisputed effects on the brain function. There is now substantial evidence that dietary nutrition aids in the prevention and remediation of neurologic symptoms in diverse pathological conditions. The newly described influences of dietary factors on the alterations of mitochondrial dysfunction, epigenetic modification and neuroinflammation are important mechanisms that are responsible for the action of nutrients on the brain health. In this review, we discuss the state of evidence supporting that distinct dietary interventions including dietary supplement and dietary restriction have the ability to tackle neurological disorders using Alzheimer's disease, Parkinson's disease, stroke, epilepsy, traumatic brain injury, amyotrophic lateral sclerosis, Huntington's disease and multiple sclerosis as examples. Additionally, it is also highlighting that diverse potential mechanisms such as metabolic control, epigenetic modification, neuroinflammation and gut-brain axis are of utmost importance for nutrient supply to the risk of neurologic condition and therapeutic response. Finally, we also highlight the novel concept that dietary nutrient intervention reshapes metabolism-epigenetics-immunity cycle to remediate brain dysfunction. Targeting metabolism-epigenetics-immunity network will delineate a new blueprint for combating neurological weaknesses.

Deciphering the key mechanisms leading to alteration of lipid metabolism in Drosophila model of Huntington's disease

Huntington's disease (HD) is an inherited, progressively debilitating disorder marked by prominent degeneration in striatal and cortical brain regions. HD is caused by (CAG)_n repeat expansion in huntingtin (HTT) gene that translates into a mutant form of the ubiquitously present Huntingtin (HTT) protein. Extensive metabolic dysfunction coexisting with overt neuropathies has been evidenced in clinical and experimental settings of HD. Body weight loss despite normal to high caloric intake remains a critical determinant of the disease progression and a challenge for therapeutic interventions. In the present study, we intended to monitor the cellular and molecular perturbations in Drosophila, caused by pan-neuronal expression of mHTT (mutant Huntingtin) protein. We found aberrant transcription profile of key lipolytic and lipogenic genes in whole-body of the fly with disease progression. Interestingly, fatbody undergoes extensive alteration of vital cellular processes and eventually surrenders to increased apoptotic cell death in terminal stage of the disease. Extensive mitochondrial dysfunction from early disease stage along with calcium derangement at terminal stage were observed in fatbody, which contribute to its deteriorating integrity. All the mechanisms were monitored progressively, at different disease stages, and many alterations were documented in the early stage itself. Our study hence provides insight into the mechanisms through which neuronal expression of mHTT might be inflicting the profound systemic effects, specifically on lipid metabolism, and may open new therapeutic avenues for alleviation of the multidimensional disease.

Therapeutic and Mechanistic Effects of Curcumin in Huntington's Disease

Curcumin is a spice derived nutraceutical which gained tremendous attention because of its profound medicinal values. It alters a number of molecular pathways such as nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), signal transducer and activator of transcription 3 (STAT3), nuclear factor erythroid 2-related factor 2 (Nrf2) and cyclooxygenases-2 (COX-2), which make it potential therapeutic choice in treating multiple disorders. It also possesses the potential to prevent protein aggregation and thus protect against degeneration of neurons in neurodegenerative disorders including Huntington's disease (HD). HD is an autosomal dominant disorder linked with altered gene expression which leads to an increase in the size of cytosine, adenine and guanine (CAG) trinucleotide repeats, aids in protein aggregation throughout the brain and thus damages neurons. Upstream regulation of oxidative stress and inflammatory cascade are two important factors that drive HD progression. Available therapies just suppress the severity of symptoms with a number of side effects. Curcumin targets multiple mechanisms in treating or preventing HD including antioxidant and anti-inflammatory potential, metal ion chelation, transcriptional alterations and upregulating activity of molecular chaperons, heat shock proteins (HSPs). Having a favorable safety profile, curcumin can be an alternative therapeutic choice in treating neurodegenerative disorders like HD. This review will focus on mechanistic aspects of curcumin in treating or preventing HD and its potential to arrest disease progression and will open new dimensions for safe and effective therapeutic agents in diminishing HD.

Melatonin and curcumin reestablish disturbed circadian gene expressions and restore locomotion ability and eclosion behavior in Drosophila model of Huntington's disease

Deficit in locomotion (motor) ability and disturbance of the circadian behavior and sleep-wake pattern characterize Huntington's disease (HD). Here, we examined the disturbance of circadian timing with the progression of HD pathogenesis, and tested the efficacy of melatonin and curcumin in preventing the motor deficit and disturbed eclosion behavior in the Drosophila model of HD. To examine circadian timing, we assayed mRNA expression of genes of the transcriptional feedback (TF) loop that generates the near 24-h rhythmicity. We performed qPCR of the Period, Timeless, Clock, Cycle, Clockwork, and Cryptochrome genes in transgenic fly heads from elav-Gal4 (pan neuronal) and PDF-Gal4 (PDF-specific neurons) driver lines through the progression of HD disease post-eclosion, from day 1 to its terminal stage on day 13. Cycle was arrhythmic from day 1, but Period and Timeless became arrhythmic on day 13 of the HD pathogenesis in elav, but not PDF, neurons. Twenty-four-hour mRNA rhythms showed alteration in the waveform properties (mesor and amplitude, not acrophase), but not in the persistence, in both elav-Gal4 and PDF-Gal4 HD flies; however, disturbance of the clock gene rhythm was delayed in PDF-Gal4 flies. To assess the preventive effects on HD pathogenesis, flies of both driver lines were provided with melatonin (50, 100, or 150 μg) or curcumin (10 μM) in the diet commencing from the larval stage. Both melatonin (100 μg) and curcumin reestablished the 24-h pattern in mRNA expression of Period and Timeless to normal (control) levels, and significantly improved both locomotion ability and eclosion behavior of HD flies. We suggest that the disturbance of circadian timekeeping progressively accelerated HD pathogenesis, possibly via modulation of the transcriptional state that resulted in the modification of the Huntington gene. These findings suggest melatonin and curcumin might be potential therapeutic agents for the treatment of HD in humans, although this needs specific investigation.

Combating silver nanoparticle-mediated toxicity in Drosophila melanogaster with curcumin

Nanoscale materials display unique physical and chemical properties that enable their assimilation into a variety of industrial and consumer products. Amongst the widely used nanomaterials, silver nanoparticles (AgNPs) have gained tremendous recognition for various applications, owing to their extraordinary plasmonic and bactericidal properties. Despite of the extensive usage of AgNPs in various sectors, its impact on human health remains ambiguous. Several studies have established that higher doses of AgNPs are detrimental to organismal health. In order to attain the best from these versatile nanoparticles, a recent advent of green nanotechnology, that is, employment of metal nanoparticles synthesized using plant extracts, has emerged. Here, using Drosophila as a model system, we tested if adding curcumin, a biologically active polyphenolic compound present in turmeric, having multitudes of therapeutic properties, could mitigate AgNP-mediated biotoxicity. We found that co-administration of AgNPs with curcumin in the fly food could alleviate several harmful effects evoked by AgNPs ingestion in Drosophila model. Addition of curcumin superseded reduction in feeding, pupation, eclosion, pigmentation, and fertility caused by AgNPs ingestion. Interestingly, impairment in ovary development observed in flies reared on AgNPs-supplemented food was also partially restored by co-administration of AgNPs with curcumin. Furthermore, substantial alleviation of reactive oxygen species level and cell death was observed in larval tissues upon co-supplementation of AgNPs with curcumin. We therefore propose that curcumin, when administered with AgNPs, can abrogate the toxic manifestations of AgNPs ingestion and hence can be incorporated in various consumer products encompassing it.

Ellagic acid rescues motor and cognitive deficits in the R6/2 mouse model of Huntington's disease by lowering mutant huntingtin protein

Huntington's disease (HD) is a genetic neurodegenerative disorder caused by a highly polymorphic CAG trinucleotide repeat expansion encoding an extended polyglutamine (polyQ) tract at the N-terminus of huntingtin protein (HTT). The polyQ tract promotes the formation of toxic oligomers and aggregates of HTT, which leads to neuronal dysfunction and death. Therapies to lower mutant HTT (mHTT) and its aggregates appear to be the most promising strategies. Ellagic acid (EA) has been marketed as a dietary supplement with various claimed benefits and neuroprotective effects on several neurodegenerative disorders, while its effect on mHTT pathology is still unknown. Here we reported that EA significantly attenuated motor and cognitive deficits in R6/2 mice. Moreover, EA significantly lowered mHTT levels, reduced neuroinflammation, rescued synapse loss, and decreased oxidative stress in R6/2 mouse brains. These findings indicated that EA has promising therapeutic potential for HD treatment.

Compounds that extend longevity are protective in neurodegenerative diseases and provide a novel treatment strategy for these devastating disorders

While aging is the greatest risk factor for the development of neurodegenerative disease, the role of aging in these diseases is poorly understood. In the inherited forms of these diseases, the disease-causing mutation is present from birth but symptoms appear decades later. This indicates that these mutations are well tolerated in younger individuals but not in older adults. Based on this observation, we hypothesized that changes taking place during normal aging make the cells in the brain (and elsewhere) susceptible to the disease-causing mutations. If so, then delaying some of these age-related changes may be beneficial in the treatment of neurodegenerative disease. In this review, we examine the effects of five compounds that have been shown to extend longevity (metformin, rapamycin, resveratrol, N-acetyl-l-cysteine, curcumin) in four of the most common neurodegenerative diseases (Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis). While not all investigations observe a beneficial effect of these compounds, there are multiple studies that show a protective effect of each of these lifespan-extending compounds in animal models of neurodegenerative disease. Combined with genetic studies, this suggests the possibility that targeting the aging process may be an effective strategy to treat neurodegenerative disease.

The neuroprotective effect of curcumin against Cd-induced neurotoxicity and hippocampal neurogenesis promotion through CREB-BDNF signaling pathway

Heavy metal neurotoxicity is one of the major challenges in today's era due to the large scale and widespread mechanisation of the production. However, the causative factors responsible for neurotoxicity are neither known nor do we have the availability of therapeutic approaches to deal with it. One of the major causative agents of neurotoxicity is a non-essential transition heavy metal, Cadmium (Cd), that reaches the central nervous system (CNS) through the nasal mucosa and olfactory pathway causing adverse structural and functional effects. In this study, we explored the neuroprotective efficacy of plant derived Curcumin which is reported to have pleiotropic biological activity including anti-oxidant, anti-inflammatory, anti-apoptotic, anti-carcinogenic and anti-angiogenic effects. Four different concentrations of curcumin (20, 40, 80 and 160 mg/kg of the body weight) were used to assess the behavioural, biochemical, hippocampal proteins (BDNF, CREB, DCX and Synapsin II) and histological changes in Swiss Albino mice that were pre-treated with Cd (2.5 mg/kg). The findings showed that Cd exposure led to the behavioural impairment through oxidative stress, reduction of hippocampal neurogenesis associated proteins, and degeneration of CA3 and cortical neurons. However, treatment of different curcumin concentrations had effectively restored the behavioural changes in Cd-exposed mice through regulation of oxidative stress and up-regulation of hippocampal proteins in a dose-dependent manner. Significantly, a dose of 160 mg/kg body weight was found to be glaringly effective. From this study, we infer that curcumin reverses the adverse effects of neurotoxicity induced by Cd and promotes neurogenesis.

Reactive Species in Huntington Disease: Are They Really the Radicals You Want to Catch?

Huntington disease (HD) is a neurodegenerative condition and one of the so-called rare or minority diseases, due to its low prevalence (affecting 1–10 of every 100,000 people in western countries). The causative gene, HTT, encodes huntingtin, a protein with a yet unknown function. Mutant huntingtin causes a range of phenotypes, including oxidative stress and the activation of microglia and astrocytes, which leads to chronic inflammation of the brain. Although substantial efforts have been made to find a cure for HD, there is currently no medical intervention able to stop or even delay progression of the disease. Among the many targets of therapeutic intervention, oxidative stress and inflammation have been extensively studied and some clinical trials have been promoted to target them. In the present work, we review the basic research on oxidative stress in HD and the strategies used to fight it. Many of the strategies to reduce the phenotypes associated with oxidative stress have produced positive results, yet no substantial functional recovery has been observed in animal models or patients with the disease. We discuss possible explanations for this and suggest potential ways to overcome it.

Circadian Clocks Function in Concert with Heat Shock Organizing Protein to Modulate Mutant Huntingtin Aggregation and Toxicity

Neurodegenerative diseases commonly involve the disruption of circadian rhythms. Studies indicate that mutant Huntingtin (mHtt), the cause of Huntington’s disease (HD), disrupts circadian rhythms often before motor symptoms are evident. Yet little is known about the molecular mechanisms by which mHtt impairs circadian rhythmicity and whether circadian clocks can modulate HD pathogenesis. To address this question, we used a Drosophila HD model. We found that both environmental and genetic perturbations of the circadian clock alter mHtt-mediated neurodegeneration. To identify potential genetic pathways that mediate these effects, we applied a behavioral platform to screen for clock-regulated HD suppressors, identifying a role for Heat Shock Protein 70/90 Organizing Protein (Hop). Hop knockdown paradoxically reduces mHtt aggregation and toxicity. These studies demonstrate a role for the circadian clock in a neurodegenerative disease model and reveal a clock-regulated molecular and cellular pathway that links clock function to neurodegenerative disease.

Disruption of circadian rhythms is frequently observed across a range of neurodegenerative diseases. Here, Xu et al. demonstrate that perturbation of circadian clocks alters the toxicity of the mutant Huntingtin protein, the cause of Huntington’s disease (HD). Moreover, they reveal a key mechanistic link between the clock and HD.

Dysregulated Brain Cholesterol Metabolism Is Linked to Neuroinflammation in Huntington's Disease

Huntington's disease is an autosomal-dominant, neurodegenerative disorder caused by a CAG repeat expansion in exon-1 of the huntingtin gene. Alterations in cholesterol metabolism and distribution have been reported in Huntington's disease, including abnormal interactions between mutant huntingtin and sterol regulatory element-binding proteins, decreased levels of apolipoprotein E/cholesterol/low-density lipoprotein receptor complexes, and alterations in the synthesis of ATP-binding cassette transporter A1. Plasma levels of 24S-hydroxycholestrol, a key intermediary in cholesterol metabolism and a possible marker in neurodegenerative diseases, decreased proportionally to the degree of caudate nucleus atrophy. The interaction of mutant huntingtin with sterol regulatory element-binding proteins is of particular interest given that sterol regulatory element-binding proteins play a dual role: They take part in lipid and cholesterol metabolism, but also in the inflammatory response that induces immune cell migration as well as toxic effects, particularly in astrocytes. This work summarizes current evidence on the metabolic and immune implications of sterol regulatory element-binding protein dysregulation in Huntington's disease, highlighting the potential use of drugs that modulate these alterations. © 2020 International Parkinson and Movement Disorder Society.

New Synthetic 3-Benzoyl-5-Hydroxy-2H-Chromen-2-One (LM-031) Inhibits Polyglutamine Aggregation and Promotes Neurite Outgrowth through Enhancement of CREB, NRF2, and Reduction of AMPKα in SCA17 Cell Models

Spinocerebellar ataxia type 17 (SCA17) is caused by a CAG/CAA expansion mutation encoding an expanded polyglutamine (polyQ) tract in TATA-box binding protein (TBP), a general transcription initiation factor. Suppression of cAMP-responsive element binding protein- (CREB-) dependent transcription, impaired nuclear factor erythroid 2-related factor 2 (NRF2) signaling, and interaction of AMP-activated protein kinase (AMPK) with increased oxidative stress have been implicated to be involved in pathogenic mechanisms of polyQ-mediated diseases. In this study, we demonstrated decreased pCREB and NRF2 and activated AMPK contributing to neurotoxicity in SCA17 SH-SY5Y cells. We also showed that licochalcone A and the related in-house derivative compound 3-benzoyl-5-hydroxy-2H-chromen-2-one (LM-031) exhibited antiaggregation, antioxidative, antiapoptosis, and neuroprotective effects in TBP/Q₇₉-GFP-expressing cell models. LM-031 and licochalcone A exerted neuroprotective effects by upregulating pCREB and its downstream genes, BCL2 and GADD45B, and enhancing NRF2. Furthermore, LM-031, but not licochalcone A, reduced activated AMPKα. Knockdown of CREB and NRF2 and treatment of AICAR (5-aminoimidazole-4-carboxamide 1-β-D-ribofuranoside), an AMPK activator, attenuated the aggregation-inhibiting and neurite outgrowth promoting effects of LM-031 on TBP/Q₇₉ SH-SY5Y cells. The study results suggest the LM-031 as potential therapeutics for SCA17 and probable other polyQ diseases.

Bioactive Polyphenols and Neuromodulation: Molecular Mechanisms in Neurodegeneration

The interest in dietary polyphenols in recent years has greatly increased due to their antioxidant bioactivity with preventive properties against chronic diseases. Polyphenols, by modulating different cellular functions, play an important role in neuroprotection and are able to neutralize the effects of oxidative stress, inflammation, and apoptosis. Interestingly, all these mechanisms are involved in neurodegeneration. Although polyphenols display differences in their effectiveness due to interindividual variability, recent studies indicated that bioactive polyphenols in food and beverages promote health and prevent age-related cognitive decline. Polyphenols have a poor bioavailability and their digestion by gut microbiota produces active metabolites. In fact, dietary bioactive polyphenols need to be modified by microbiota present in the intestine before being absorbed, and to exert health preventive effects by interacting with cellular signalling pathways. This literature review includes an evaluation of the literature in English up to December 2019 in PubMed and Web of Science databases. A total of 307 studies, consisting of research reports, review articles and articles were examined and 146 were included. The review highlights the role of bioactive polyphenols in neurodegeneration, with a particular emphasis on the cellular and molecular mechanisms that are modulated by polyphenols involved in protection from oxidative stress and apoptosis prevention.

Discovery of Arginine Ethyl Ester as Polyglutamine Aggregation Inhibitor: Conformational Transitioning of Huntingtin N-Terminus Augments Aggregation Suppression

Huntington's disease (HD) is a genetic disorder caused by a CAG expansion mutation in the huntingtin gene leading to polyglutamine (polyQ) expansion in the N-terminal part of huntingtin (Httex1). Expanded polyQ, through a complex aggregation pathway, forms aggregates in neurons and presents a potential therapeutic target. Here we show Httex1 aggregation suppression by arginine and arginine ethyl ester (AEE) in vitro, as well as in yeast and mammalian cell models of HD, bearing expanded polyQ. These molecules also rescue locomotion dysfunction in HD Drosophila model. Both molecules alter the hydrogen bonding network of polyQ to enhance its aqueous solubility and delay aggregation. AEE shows direct binding with the NT₁₇ part of Httex1 to induce structural changes to impart an enhanced inhibitory effect. This study provides a platform for the development of better arginine based therapeutic molecules against polyQ-rich Httex1 aggregation.

Curcumin Attenuates Lead-Induced Cerebellar Toxicity in Rats via Chelating Activity and Inhibition of Oxidative Stress

Lead (Pb) is a toxic, environmental heavy metal that induces serious clinical defects in all organs, with the nervous system being its primary target. Curcumin is the main active constituent of turmeric rhizome (Curcuma longa) with strong antioxidant and anti-inflammatory properties. This study is aimed at evaluating the therapeutic potentials of curcumin on Pb-induced neurotoxicity. Thirty-six male Sprague Dawley rats were randomly assigned into five groups with 12 rats in the control (normal saline) and 6 rats in each of groups, i.e., the lead-treated group (LTG) (50 mg/kg lead acetate for four weeks), recovery group (RC) (50 mg/kg lead acetate for four weeks), treatment group 1 (Cur100) (50 mg/kg lead acetate for four weeks, followed by 100 mg/kg curcumin for four weeks) and treatment group 2 (Cur200) (50 mg/kg lead acetate for four weeks, followed by 200 mg/kg curcumin for four weeks). All experimental groups received oral treatment via orogastric tube on alternate days. Motor function was assessed using a horizontal bar method. The cerebellar concentration of Pb was evaluated using ICP-MS technique. Pb-administered rats showed a significant decrease in motor scores and Superoxide Dismutase (SOD) activity with increased Malondialdehyde (MDA) levels. In addition, a marked increase in cerebellar Pb concentration and alterations in the histological architecture of the cerebellar cortex layers were recorded. However, treatment with curcumin improved the motor score, reduced Pb concentration in the cerebellum, and ameliorated the markers of oxidative stress, as well as restored the histological architecture of the cerebellum. The results of this study suggest that curcumin attenuates Pb-induced neurotoxicity via inhibition of oxidative stress and chelating activity.

Benefits of curcumin in brain disorders

Curcumin is widely consumed in Asia either as turmeric directly or as one of the culinary ingredients in food recipes. The benefits of curcumin in different organ systems have been reported extensively in several neurological diseases and cancer. Curcumin has got its global recognition because of its strong antioxidant, anti-inflammatory, anti-cancer, and antimicrobial activities. Additionally, it is used in diabetes and arthritis as well as in hepatic, renal, and cardiovascular diseases. Recently, there is growing attention on usage of curcumin to prevent or delay the onset of neurodegenerative diseases. This review summarizes available data from several recent studies on curcumin in various neurological diseases such as Alzheimer's disease, Parkinson's disease, Multiple Sclerosis, Huntington's disease, Prions disease, stroke, Down's syndrome, autism, Amyotrophic lateral sclerosis, anxiety, depression, and aging. Recent advancements toward increasing the therapeutic efficacy of curcuma/curcumin formulation and the novel delivery strategies employed to overcome its minimal bioavailability and toxicity studies have also been discussed. This review also summarizes the ongoing clinical trials on curcumin for different neurodegenerative diseases and patent details of curcuma/curcumin in India.

Therapeutic effects of turmeric in several diseases: An overview

A nutraceutical product can be defined as a substance that has a physiological benefit or provides protection against chronic diseases. The term nutraceutical is a hybrid term derived from the union of "nutrition" and "pharmaceutical". The list of studied nutraceuticals is constantly changing and reflects ongoing market developments, research and consumer interest. Spices, in addition to giving color and taste to foods, are also important nutraceutical. Spices have been an integral part of human diets and commerce for millennia but recently, the recognition of the link between health and nutrition has strengthened their importance in the food sector and sparked the interest of researchers who increasingly engage in trying to determine the mechanisms of action of spices and the countless beneficial properties attributed to them. Among the many existing spices, turmeric is one of the most studied for its antioxidant, anti-inflammatory, antibacterial and anticancer properties. The purpose of this review is to briefly summarize the fundamental characteristics of turmeric and give an overview of the use of this spice in several diseases.

Modulation of Biological Activities in Glioblastoma Mediated by Curcumin

Curcumin is an alkaloid with various pharmacologic properties; numerous investigations have suggested that in the Central Nervous System, Curcumin has anti-inflammatory, antimicrobial, antioxidant, and antitumor effects. Gliomas are the most common primary intracranial tumors in adults. The prognosis of glioblastoma is still dismal. In this review, we profile that Curcumin could suppress cell proliferation and induce apoptosis of cancer cells and genomic modulation. In particular, Curcumin could exert its therapeutic effect via modulating miRNA, affecting a variety of miRNAs involved in the response to cancer therapy. The combination of Curcumin with chemotherapeutic drugs or radiotherapy could prime the sensitivity of cancer cells to chemotherapy or radiotherapy. We also discuss the use of exosomes as Curcumin delivery vehicles. In this context, exosomes containing Curcumin may change the behavior of recipient cells by targeting a sequence of cellular and molecular pathways. Hence, the application of exosomes containing Curcumin may prove to be an emerging area of research in cancer therapy.

Assessment of epigenetic changes and oxidative DNA damage in rat pups exposed to polychlorinated biphenyls and the protective effect of curcumin in the prenatal period

Background Polychlorinated biphenyls (PCBs) are persistent organic chemicals that exert neurotoxic and endocrine disrupting effects. The aims of this study were to examine the effects of prenatal Aroclor 1254 (PCBs mixture) exposure on central nervous system tissues DNA and to evaluate the effects of curcumin. Methods Rat pups were assigned to three groups: [Group 1], Aroclor 1254 administrated group; [Group 2], Aroclor 1254 and curcumin administrated group; and [Group 3], control group. Plasma, cerebrum, cerebellum, pons and medulla oblongata tissue homogenates 8-hydroxy-2'-deoxyguanosine [8-(OH)DG] levels and plasma freeT4 levels were determined. Global DNA methylation and hydroxymethylation status were determined in cerebrum, cerebellum, pons and medulla oblongata. To this aim, DNA 5-hydroxymethylcytosine and 5-methylcytosine levels were measured, respectively. Results Mean cerebellum and cerebral cortex 5-hydroxymethylcytosine and 5-methylcytosine levels were higher in the control group than in the experimental groups. Mean plasma, cerebellum and cerebral cortex 8-(OH)DG concentrations were higher in Group 1 than the control group. No statistically significant difference was observed between Group 2 and the control group in terms of cerebellum and cerebral cortex 8-(OH)DG concentrations. Histopathological changes were also observed in the cerebral cortex and cerebellum of rat pups exposed to Aroclor 1254. PCBs exposure changes both DNA methylation and hypomethylation status and induces cerebellar and cerebral cortex DNA damage in the prenatal period. Exogenous curcumin may have protective effect on PCBs-induced DNA damage in cerebellum and cerebral cortex.