Ellagic acid supports neuron by regulating astroglia Nrf2

Ellagic acid ameliorates arsenic-induced neuronal ferroptosis and cognitive impairment via Nrf2/GPX4 signaling pathway

Arsenic, a neurotoxic metalloid, poses significant health risks. However, ellagic acid, renowned for its antioxidant properties, has shown potential in neuroprotection. This study aimed to investigate the neuroprotective effects of ellagic acid against arsenic-induced neuronal ferroptosis and cognitive impairment and elucidate the underlying mechanisms. Using an arsenic-exposed Wistar rat model and an arsenic-induced HT22 cells model, we assessed cognitive ability, measured serum and brain arsenic levels, and evaluated pathological damage through histological analysis and transmission electron microscopy. Additionally, we examined oxidative stress and iron ion levels using GSH, MDA, ROS and tissue iron biochemical kits, and analyzed the expression of ferroptosis-related markers using western blot and qRT-PCR. Our results revealed that arsenic exposure increased both serum and brain arsenic levels, resulting in hippocampal pathological damage and subsequent decline in learning and memory abilities. Arsenic-induced neuronal ferroptosis was mediated by the inhibition of the xCT/GSH/GPX4/Nrf2 signaling axis and disruption of iron metabolism. Notably, ellagic acid intervention effectively reduced serum and brain arsenic levels, ameliorated neuronal damage, and improved oxidative stress, ferroptosis, and cognitive impairment. These beneficial effects were associated with the activation of the Nrf2/Keap1 signaling pathway, upregulation of GPX4 expression, and enhanced iron ion excretion. In conclusion, ellagic acid demonstrates promising neuroprotective effects against arsenic-induced neurotoxicity by mitigating neuronal ferroptosis and cognitive impairment.

Brazil Nut-Enriched Diet Modulates Enteric Glial Cells and Gut Microbiota in an Experimental Model of Chronic Kidney Disease

Introduction: Chronic kidney disease (CKD) promotes gut dysbiosis, and enteric glial reactivity, a feature of intestinal inflammation. Brazil nut modulated enteric glial profile in healthy animals and could modulate these cells in 5/6 nephrectomized rats.Methods: A 5/6 nephrectomy-induced CKD and Sham-operated rats were divided as follows: CKD and Sham received a standard diet and CKD-BN and Sham-BN received a 5% Brazil nut enriched-diet. The protein content of glial fibrillary acid protein (GFAP), enteric glial marker, and GPx protein content and activity were assessed in the colon. The major phyla of gut microbiota were assessed.Results: CKD-BN group presented a decrease in GFAP content (p = 0.0001). The CKD-BN group modulated the abundance of Firmicutes, increasing its proportion compared to the CKD group. The CKD-BN group showed increased GPx activity in the colon (p = 0.0192), despite no significant difference in protein content.Conclusion: Brazil nut-enriched diet consumption decreased enteric glial reactivity and modulated gut microbiota in the CKD experimental model.

Ellagic acid: insight into its protective effects in age-associated disorders

The disparity in the free radical generation and the production of antioxidants to counteract its effect is known as oxidative stress. Oxidative stress causes damage to the macromolecules such as lipids, carbohydrates, proteins, and DNA and RNA. The oxidative damage to the cellular components leads to a process of aging and various age-associated disorders. The literature survey for this review was done using PubMed, Google Scholar, and Science Direct. The papers showing the studies related to aging and age-associated disorders have been selected for reviewing this paper. Ellagic acid has been used as the keyword, and more emphasis has been put on papers from the last 10 years. However, some papers with significant studies prior to 10 years have also been considered. Almost 250 papers have been studied for reviewing this paper, and about 135 papers have been cited. Ellagic acid (EA) is present in high quantities in pomegranate and various types of berries. It is known to possess the antioxidant potential and protects from the harmful effects of free radicals. Various studies have shown its effect to protect cardiovascular, neurodegenerative, cancer, and diabetes. The present review focuses on the protective effect of ellagic acid in age-associated disorders. The effect of EA has been studied in various chronic disorders but the scope of this review is limited to cancer, diabetes, cardiovascular and neurodegenerative disorders. All the disease aspects have not been addressed in this particular review.

Brazil Nut (Bertholletia excelsa H.B.K) Retards Gastric Emptying and Modulates Enteric Glial Cells in a Dose-Dependent Manner

BACKGROUND

The role of food and nutrients in the regulation of enteric glial cell functions is unclear. Some foods influence enteric neurophysiology and can affect glial cell functions that include regulation of the intestinal barrier, gastric emptying, and colonic transit. Brazil nuts are the most abundant natural source of selenium, unsaturated fatty acids, fibers, and polyphenols.

OBJECTIVE

The study investigated the effects of a Brazil nut-enriched diet on enteric glial cells and gastrointestinal transit.

METHODS

Two-month-old male Wistar rats were randomized to a standard diet (control group, CG), standard diet containing 5% (wt/wt) Brazil nut (BN5), and standard diet containing 10% (wt/wt) Brazil nut (BN10) (n = 9 per group). After eight weeks, the animals underwent constipation and gastric emptying tests to assess motility. Evaluations of colonic immunofluorescence staining for glial fibrillary acidic protein (GFAP) and myenteric ganglia area were performed.

RESULTS

The BN5 group showed increased weight gain while the BN10 group did not (p < 0.0001). The BN10 group showed higher gastric residue amounts compared to the other groups (p = 0.0008). The colon exhibited an increase in GFAP immunoreactivity in the BN5 group compared to that in the other groups (p = 0.0016), and the BN10 group presented minor immunoreactivity compared to the CG (p = 0.04). The BN10 group presented a minor ganglia area compared to the CG (p = 0.0155).

CONCLUSION

The Brazil nut-enriched diet modified the gastric residual, colonic GFAP immunoreactivity, and myenteric ganglia area after eight weeks in healthy male Wistar rats.

Ellagic Acid Alleviates Oxidative Stress by Mediating Nrf2 Signaling Pathways and Protects against Paraquat-Induced Intestinal Injury in Piglets

The gastrointestinal tract is a key source of superoxide so as to be one of the most vulnerable to oxidative stress damage. Ellagic acid (EA), a polyphenol displays widely biological activities owing to its strong antioxidant properties. Here, we investigated the protective benefits of EA on oxidative stress and intestinal barrier injury in paraquet (PQ)-challenged piglets. A total of 40 weaned piglets were randomly divided into five groups: Control, PQ, 0.005% EA-PQ, 0.01% EA-PQ, and 0.02% EA-PQ. Piglets were intraperitoneally injected with 4 mg/kg (BW) PQ or saline on d-18, and sacrificed on d-21 of experiment. EA treatments eliminated growth-check induced by PQ and increased serum superoxide dismutase (SOD) activity but decreased serum malondialdehyde (MDA) level as compared to PQ group. EA supplementation promoted Nrf2 nuclear translocation and enhanced heme oxygenase-1 (HO-1) and quinone oxidoreductase 1 (NQO1) protein abundances of small intestinal mucosa. Additionally, EA improved PQ-induced crypt deepening, goblet cells loss, and villi morphological damage. Consistently, EA increased tight junction protein expression as was evident from the decreased serum diamine oxidase (DAO) levels. EA could ameliorate the PQ-induced oxidative stress and intestinal damage through mediating Nrf2 signaling pathway. Intake of EA-rich food might prevent oxidative stress-mediated gut diseases.

Plant-Derived Antioxidants Protect the Nervous System From Aging by Inhibiting Oxidative Stress

Alzheimer's disease (AD) has become a major disease contributing to human death and is thought to be closely related to the aging process. The rich antioxidant substances in plants have been shown to play a role in delaying aging, and in recent years, significant research has focused on also examining their potential role in AD onset and progression. Many plant-derived antioxidant research studies have provided insights for the future treatment and prevention of AD. This article reviews various types of plant-derived antioxidants with anti-aging effects on neurons. Also it distinguishes the different types of active substances that exhibit different degrees of protection for the nervous system and summarizes the mechanism thereof. Plant-derived antioxidants with neuroprotective functions can protect various components of the nervous system in a variety of ways and can have a positive impact on interventions to prevent and alleviate AD. Furthermore, when considering neuroprotective agents, glial cells also contribute to the defense of the nervous system and should not be ignored.

The effect of ellagic acid on spinal cord and sciatica function in a mice model of multiple sclerosis

Multiple sclerosis (MS) is a well-known neurodegenerative disorder, causing toxicity in different organs, such as spinal cord tissue. The goal of this study was to investigate the protective effect of ellagic acid (EA) against spinal cord and sciatica function in cuprizone (Cup)-induced demyelination model. Animals were divided into six equal groups. The first group received tap water as the control. Cup group was treated with Cup (0.2% w/w in fed). EA 100 group was orally treated with EA (100 mg/kg). EA + Cup groups were orally treated with three doses of 5, 50, and 100 mg/kg of EA plus Cup (0.2% w/w). All groups received treatment for 42 days. Open field, rotarod, and gait tests were done to evaluate the behavioral changes following Cup and/or EA treatment. Also, lipid peroxidation, reactive oxygen species (ROS) content, antioxidant capacity, superoxide dismutase (SOD), and catalase enzymes activity in spinal cord was evaluated. Luxol fast blue (LFB) staining also the behavioral tests were performed to evaluate the model. Cup increased ROS levels and oxidative stress in their spinal cord tissues. Also, Cup reduced antioxidant capacity, SOD, and catalase activity. EA (especially at 100 mg/kg) prevented these abnormal changes. EA co-treatment dose-dependently was able to ameliorate behavioral impairments in mice that received Cup. EA might act as a protective agent in MS by modulating spinal cord function.