Nanonaringenin and Vitamin E Ameliorate Some Behavioral, Biochemical, and Brain Tissue Alterations Induced by Nicotine in Rats

Effect of perinatal nicotine exposure on oxidative stress and BDNF levels in the brain tissue of offspring rats: The protective role of Vitamin E

OBJECTIVE

Nicotine, a well-known neurotoxin, induces oxidative stress in fetal tissues, leading to organ damage and fetal growth retardation. This study aims to evaluate oxidative stress parameters in the brain tissue of rat offspring exposed to perinatal nicotine and assess vitamin E's protective effects.

METHODS

Twenty-five pregnant rats were administered 10 mg/L of nicotine and 300 mg/L of Vitamin E in drinking water starting from the first day of gestation. On gestational day 21, some offspring were euthanized to form the prenatal group. The remaining litters were born naturally, and dams received treatments via drinking water during gestation and lactation (6 weeks). After the lactation period, the pups were weaned and directly treated for an additional 9 weeks, resulting in an overall treatment duration of 15 weeks. Brain tissues were analyzed for MDA, GSH, TOS, TAS, OSI, BDNF, Caspase-3 activity, and histopathological changes.

RESULTS

The nicotine-exposed pups exhibited significantly reduced crown-rump length, body mass, and brain mass compared to controls. Nicotine exposure decreased BDNF, GSH, and TAS levels and increased MDA, TOS, and OSI levels. Histopathologically, the nicotine prenatal group showed a significantly higher number of heterochromatic nuclei in brain tissue. Caspase-3 activity did not show a significant increase in nicotine groups compared to the control. Vitamin E supplementation mitigated nicotine-induced brain damage in some measured parameters.

CONCLUSION

Perinatal nicotine exposure induces oxidative damage in the brain tissue of rat offspring, while vitamin E exerts a protective antioxidant effect, preventing nicotine-induced neurotoxicity. Furthermore, the significant reduction in BDNF levels and the increase in heterochromatic nuclei in the nicotine-exposed groups highlight the detrimental impact of nicotine on neurodevelopment, which can be effectively mitigated by vitamin E supplementation.

Zinc or/and Vitamin E Supplementation Mitigates Oxidative Stress, Neuroinflammation, Neurochemical Changes and Behavioural Deficits in Male Wistar Rats Exposed to Bonny Light Crude Oil

Background: Crude oil, a major key economic driver in developing countries, is also of environmental concern, linked to neurotoxicity and behavioural problems. Despite the known neurotoxic effects of crude oil and the potential benefits of zinc and vitamin E, there is a paucity of research specifically addressing their combined efficacy in mitigating neurochemical changes and behavioural deficits induced by crude oil. Current studies have largely focussed on the individual effects of these supplements in different contexts, but their synergistic potential in a crude oil exposure model remains underexplored. This study investigated the potential effects of zinc and vitamin E on neurobehavioural alterations in male Wistar rats fed with Bonny light crude oil (BLCO)-contaminated diet. Methods: Thirty (30) male Wistar rats (160 ± 10 g) were assigned into five groups (n = 6). Group 1 received standard rat feed, Group 2 was exposed to BLCO (0.1 mL/g of rat feed) for 3 weeks, and groups 3-5 were treated with zinc (50 mg/kg/day), vitamin E (400 IU/kg), or both [vitamin E (400 IU/kg) + zinc (50 mg/kg/day)], respectively for 1 week after BLCO exposure for 3 weeks. Locomotive, anxiolytic, depressive-like behaviours and spatial memory were assessed using the open-field test, elevated plus maze, forced swim test and Y-maze. Rats were sacrificed and the brain samples were collected for biochemical assays at the end of the behavioural tests. Results: Zinc and vitamin E supplementation (individually or combined) significantly increased brain total antioxidant capacity and superoxide dismutase (SOD) activity, reduced inflammatory markers (TNF-alpha) and lipid peroxidation, normalized neurotransmitter levels in the brain and improved behavioural performance. Conclusion: Treatment with Zn and/or vitamin E reverses BLCO-induced neurobehavioural alterations via modulation of oxidative stress, inflammation and neurotransmitters.

The mechanisms of learning and memory impairment caused by nonylphenol: a narrative review based on in vivo and in vitro studies

Learning and memory play a fundamental role on brain cognitive functions which are crucial for human life. Nonylphenol (NP), a serious environmental pollutant over the world, is proven to be harmful for learning and memory mainly via diet exposure. Currently, besides the administrative restrictions for the use of NP, there are rarely other effective approaches against learning and memory impairment caused by NP. This review summarized the mechanisms underlying NP-induced learning and memory impairment according to in vivo and in vitro experiments. Based on the studies involved in behavior tests, these mechanisms were classified as oxidative stress, neurotransmitter disorder, synaptic plasticity impairment, and neuron injury. In addition, according to the studies which did not conduct behavior tests, the possible mechanisms underlying NP-induced learning and memory impairment were proposed as chronic inflammation and gut permeability increment. Furthermore, this review also revealed the demanding questions for the mechanism investigations and therapeutic methods. Notably, the summarized mechanisms might accelerate the prevention and remediation of NP-induced learning and memory impairment.

Enhanced Antioxidant Effects of Naringenin Nanoparticles Synthesized using the High-Energy Ball Milling Method

Naringenin, one of the flavonoid components, is majorly found in and obtained from grapefruits and oranges. Naringenin also acts as a potent antioxidant, which possesses hypolipidemic as well as anti-inflammatory potential. Naringenin reduces the expressions of several inflammatory mediators, viz., NF-κB, cycloxygenase-2, and other cytokine mediators. In spite of having various biological effects, the clinical application of naringenin is restricted due to its very poor aqueous solubility. In the present study, the high-energy ball milling method was employed for the preparation of naringenin nanoparticles without using any chemical with an aim to enhance the anti-oxidant potential of naringenin. The milled naringenin nanoparticles were characterized for their physicochemical properties using scanning electron microscopy (SEM) and X-ray diffraction. Additionally, the effects of milling time and temperature were further assessed on the solubility of crude and milled naringenin samples. The antioxidant potential of milled naringenin was evaluated with various assays such as DHE, DCFDA, and cleaved caspase-3 using SH-SY5Y human neuroblastoma cells. The nanoparticle size of naringenin after milling was confirmed using SEM analysis. Crystalline peaks for milled and crude samples of naringenin also established that both the naringenin forms were in the crystalline form. The solubility of naringenin was enhanced depending on the milling time and temperature. Moreover, crude and milled naringenin were found to be cytocompatible up to doses of 120 μM each for the duration of 24 and 48 h. It was also observed that milled naringenin at the doses of 1, 2, and 5 μM significantly reduced the levels of reactive oxygen species (ROS) generated by H₂O₂ and exhibited superior ROS scavenging effects as compared to those of crude or un-milled forms of naringenin. Furthermore, milled naringenin at the doses of 1 and 2 μM inhibited H₂O₂-induced cell death, as shown by immunofluorescence staining of cleaved caspase-3 and Annexin-V PI flow cytometry analysis. Conclusively, it could be suggested that the size reduction of naringenin using high-energy ball milling techniques substantially enhanced the antioxidant potential as compared to naïve or crude naringenin, which may be attributed to its enhanced solubility due to reduced size.

Does ( -)-epigallocatechin-3-gallate protect the neurotoxicity induced by bisphenol A in vivo?

Bisphenol A (BPA) is one of the chemicals that is firmly accompanied by hippocampal neuronal injury. As oxidative stress appears to be a major contributor to neurotoxicity induced by BPA, antioxidants with remarkable neuroprotective effects can play a valuable protective role. Around the world, ( -)-epigallocatechin-3-gallate (EGCG) was one of the most popular antioxidants that could exert a beneficial neuroprotective role. Here, we examined the potential efficiency of EGCG against neurotoxicity induced by BPA in the hippocampal CA3 region of the rat model. This study revealed that EGCG was unable to abrogate the significant decrease in circulating adiponectin level and hippocampal superoxide dismutase activity as well as an increase in hippocampal levels of nitric oxide and malondialdehyde. Notably, EGCG failed to antagonize the oxidative inhibitory effect of BPA on hippocampal neurotransmission and its associated cognitive deficits. In addition, the histopathological examination with immunohistochemical detection of caspase-3 and NF-kB/p65 emphasized that EGCG failed to protect hippocampal CA3 neurons from apoptotic and necrotic effects induced by BPA. Our study revealed that EGCG showed no protective role against the neurotoxic effect caused by BPA, which may be attributed to its failure to counteract the BPA-induced oxidative stress in vivo. The controversial effect is probably related to EGCG's ability to impede BPA glucuronidation and thus, its detoxification. That inference requires further additional experimental and clinical studies.