Protective effects of Nigella sativa L. seed extract on lead induced neurotoxicity during development and early life in mouse models.
ABSTRACT: Lead (Pb), a ubiquitous heavy metal and a known neurotoxicant, produces adverse effects on the brain via increased production of reactive oxygen species (ROS) and causes oxidative stress. In this study we examined the neuroprotective effects of the ethanolic extract of Nigella sativa L. seeds on Pb induced oxidative stress in the developing brain of mice. Mouse pups were exposed to low (0.1%) and high (0.2%) doses of Pb from the first day of pregnancy through their mothers (via drinking water) and lactation until post-natal day (PND) 21. The mRNA expression levels of superoxide dismutase (SOD1), peroxiredoxin (Prdx6), amyloid precursor protein (APP) common, APP695 and APP770 were examined in the cortex and hippocampus of the mouse brain excised on PND 21 by semi-quantitative RT-PCR. The free radical scavenging activity of ethanolic Nigella sativa L. extract was assessed by DPPH assay. The results showed that Pb exposure caused a significant decrease in the expression of SOD1, Prdx6 and APP695 and an increase in APP770 in both cortex and hippocampus in a dose dependent manner as compared to the control group. The expression of APP common remained unaltered. Histological assessment of the cortex and hippocampus demonstrated a decrease in the neuronal number and Nissl bodies. The administration of 250 and 500 mg kg-1 ethanolic Nigella sativa L. extract reversed the adverse effects by significantly increasing the expression of SOD1, Prdx6 and APP695 and decreasing the expression of APP770 in both the regions. These results strongly suggest that Nigella sativa L. supplementation greatly improves Pb-induced neurotoxicity in early life and provides neuroprotective and antioxidant potentials.
Project description:Hepatitis C is a major global health burden and Egypt has the highest prevalence of hepatitis C virus (HCV) worldwide. The current study was designed to evaluate the beneficial therapeutic effects of ethanolic extracts of Nigella sativa, Zingiber officinale and their mixture in Egyptian HCV patients. Sixty volunteer patients with proven HCV and fifteen age matched healthy subjects were included in this study. Exclusion criteria included patients on interferon alpha (IFN-?) therapy, infection with hepatitis B virus, drug-induced liver diseases, advanced cirrhosis, hepatocellular carcinoma (HCC) or other malignancies, blood picture abnormalities and major severe illness. Liver function enzymes, albumin, total bilirubin, prothrombin time and concentration, international normalized ratio, alpha fetoprotein and viral load were all assessed at baseline and at the end of the study. Ethanolic extracts of Nigella sativa and Zingiber officinale were prepared and formulated into gelatinous capsules, each containing 500 mg of Nigella sativa and/or Zingiber officinale. Clinical response and incidence of adverse drug reactions were assessed initially, periodically, and at the end of the study. Both extracts as well as their mixture significantly ameliorated the altered viral load, alpha fetoprotein, liver function parameters; with more potent effect for the combined therapy. In conclusion, administration of Nigella sativa and/or Zingiber officinale ethanolic extracts to HCV patients exhibited potential therapeutic benefits via decreasing viral load and alleviating the altered liver function, with more potent effect offered by the mixture.
Project description:Obesity is associated with increased risk of Alzheimer's disease. Previous studies have demonstrated that amyloid-beta precursor protein (APP) is expressed in subcutaneous adipose tissue (SAT), upregulated with obesity, and correlates with insulin resistance and adipose tissue inflammation. APP is alternatively spliced into several isoforms, which may be indicative of the pathogenesis of APP-related diseases, but the accurate quantification has been difficult to standardize and reproduce. In light of this, we developed isoform-specific absolute cDNA standards for absolute quantitative real-time PCR (AQ-PCR), and measured transcript copy numbers for three major APP isoforms (APP770, APP751, and APP695), in SAT from C57BL/6 mice fed either a normal or high-fat diet. Expression of all three major APP isoforms was increased in diet-induced obese mice. Transcript copy numbers of APP770 and APP695 correlated with plasma insulin and CCL2 gene expression. The ratios of APP770 and APP751 to APP695 gradually decreased with aging, and correlated with plasma glucose levels. In addition, APP770 was significantly decreased in thiazolidinedione-treated mice. We describe quantification of APP isoform transcripts by AQ-PCR, which allows for direct comparison of gene copy number across isoforms, between experiments, and across studies conducted by independent research groups, which relative quantitative PCR does not allow. Our results suggest a possible role of differential expression of APP isoforms in the development of obesity-related insulin resistance and adipose tissue inflammation. In addition, it is important to determine if altered ratios of APP isoforms in SAT contribute to higher circulating Aβ peptides and increased risk of abnormalities in obesity.
Project description:Deposition of amyloid ? (A?) in the brain is closely associated with Alzheimer disease (AD). A? is generated from amyloid precursor protein (APP) by the actions of ?- and ?-secretases. In addition to A? deposition in the brain parenchyma, deposition of A? in cerebral vessel walls, termed cerebral amyloid angiopathy, is observed in more than 80% of AD individuals. The mechanism for how A? accumulates in blood vessels remains largely unknown. In the present study, we show that brain endothelial cells expressed APP770, a differently spliced APP mRNA isoform from neuronal APP695, and produced A?40 and A?42. Furthermore, we found that the endothelial APP770 had sialylated core 1 type O-glycans. Interestingly, ?-glycosylated APP770 was preferentially processed by both ?- and ?-cleavage and secreted into the media, suggesting that O-glycosylation and APP processing involved related pathways. By immunostaining human brain sections with an anti-APP770 antibody, we found that APP770 was expressed in vascular endothelial cells. Because we were able to detect O-glycosylated sAPP770? in human cerebrospinal fluid, this unique soluble APP770? has the potential to serve as a marker for cortical dementias such as AD and vascular dementia.
Project description:Lead (Pb) exposure in early life affects brain development resulting in cognitive and behavioral deficits. Epidemiologic and experimental evidence of sex as an effect modifier of developmental Pb exposure is emerging. In the present study, we investigated Pb effects on behavior and mechanisms of neuroplasticity in the hippocampus and potential sex differences. To this aim, dams were exposed, from one month pre-mating to offspring weaning, to Pb via drinking water at 5 mg/kg body weight per day. In the offspring of both sexes, the longitudinal assessment of motor, emotional, and cognitive end points was performed. We also evaluated the expression and synaptic distribution of N-methyl-D-Aspartate receptor (NMDA) and ?-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunits at post-natal day (pnd) 23 and 70 in the hippocampus. Neonatal motor patterns and explorative behavior in offspring were affected in both sexes. Pb effects in emotional response and memory retention were observed in adult females only, preceded by increased levels of GluN2A and GluA1 subunits at the post-synapse at pnd 23. These data suggest that Pb exposure during development affects glutamatergic receptors distribution at the post-synaptic spine in females. These effects may contribute to alterations in selected behavioral domains.
Project description:BACKGROUND: Oxidized low density lipoprotein plays an important role in development of foam cells in atherosclerosis. The study was focused on regulation of primary human monocyte growth and CD11b expression in presence of Nigella sativa oil. METHODS: Primary human monocytes were isolated from whole blood and grown at 37°C and 5% CO? saturation for five days prior to treatment with Nigella sativa oil. The cells were plated and washed before treatment with ox-LDL (10 ?g/ml) as positive control and combined treatment of ox-LDL (10 ?g/ml) and (140 ng/ml) Nigella sativa oil. The growth progression was monitored every 24 hours for 3 days. RESULTS: Macrophages showed reduced growth in comparison to monocytes 24 hours after treatment with Nigella sativa oil. The mean cell diameter was significantly different between untreated and treated condition in monocytes and macrophages (p < 0.001). Similarly, intracellular lipid accumulation was hindered in combined treatment with Nigella sativa oil. This was further supported by cell surface expression analysis, where CD11b was markedly reduced in cells treated with combination oxLDL and Nigella sativa oil compared to oxLDL alone. More cells differentiated into macrophage-like cells when monocytes were supplemented with oxidized LDL alone. CONCLUSIONS: The finding provides preliminary evidence on regulation of cell growth and differentiation in monocyte and monocyte-derived macrophages by Nigella sativa oil. Further investigations need to be conducted to explain its mechanism in human monocyte.
Project description:Alzheimer's disease (AD) is characterized by amyloid-β (Aβ) deposition in the brain. Aβ plaques are produced through sequential β/γ cleavage of amyloid precursor protein (APP), of which there are three main APP isoforms: APP695, APP751 and APP770. KPI-APPs (APP751 and APP770) are known to be elevated in AD, but the reason remains unclear. Transcription activator-like (TAL) effector nucleases (TALENs) induce mutations with high efficiency at specific genomic loci, and it is thus possible to knock out specific regions using TALENs. In this study, we designed and expressed TALENs specific for the C-terminus of APP in HeLa cells, in which KPI-APPs are predominantly expressed. The KPI-APP mutants lack a 12-aa region that encompasses a 5-aa trans-membrane (TM) region and 7-aa juxta-membrane (JM) region. The mutated KPI-APPs exhibited decreased mitochondrial localization. In addition, mitochondrial morphology was altered, resulting in an increase in spherical mitochondria in the mutant cells through the disruption of the balance between fission and fusion. Mitochondrial dysfunction, including decreased ATP levels, disrupted mitochondrial membrane potential, increased ROS generation and impaired mitochondrial dehydrogenase activity, was also found. These results suggest that specific regions of KPI-APPs are important for mitochondrial localization and function.
Project description:This study investigated the preventive efficacy of the crude oil extracted from Nigella sativa seeds in a rat model of arthritis induced by using complete Freund's adjuvant (CFA). Nigella sativa oil at 1.82 mL/kg or 0.91 mL/kg (corresponding to 1596 and 798 mg/kg, respectively) was orally administered for 25 days from the day of immunization. One immunized group was treated orally with indomethacin (3 mg/kg) as a reference drug. Body weight growth rate, paw swelling, arthritis score, mechanical allodynia, locomotor activity and anxiety-like behavior were observed, and the levels of Interleukin 6 (IL-6), C-reactive protein, albumin and total cholesterol in plasma were measured on days 15 and 25. Nigella sativa oil showed anti-inflammatory, anti-arthritic and anti-nociceptive activities that were significant as compared to untreated arthritic rats but less than indomethacin. These results indicated that Nigella sativa oil significantly attenuated adjuvant-arthritis in rats and the higher dose (1.82 mL/kg) prevented the development of arthritis with an inhibition of 56%.
Project description:INTRODUCTION:Lead (Pb) exposure yielding blood lead levels (BLL) as low as 2 µg/dl in children is an international problem. More common in US low-income neighborhoods, childhood Pb exposure can cause behavioral and cognitive deficits, including working memory impairments, which can persist into adulthood. So far, studies characterized short-term effects of high Pb exposure on neuronal structure and function. However, long-term consequences of early chronic Pb exposure on neuronal activity are poorly documented. METHODS:Here, we exposed male and female mice (PND [postnatal day] 0 to PND 28) to one of three Pb treatments: 0 ppm (sodium-treated water, control), 30 ppm (low dose), and 330 ppm (high dose) lead acetate. Once the male and female mice were 9-12 months old, extracellular field recordings on hippocampal slices were performed. RESULTS:We show that at CA3 to CA1 synapses, synaptic transmission was decreased and neuronal fiber activity was increased in males exposed to lowest level Pb. In contrast, both synaptic transmission and neuronal fiber activity were increased in females exposed to high Pb. The ventral hippocampus-medial prefrontal cortex (vHPC-mPFC) synapses are crucial for working memory in rodents. The lowest level Pb decreased vHPC-mPFC synaptic transmission, whereas high Pb decreased short-term synaptic depression. CONCLUSIONS:Overall, we show for the first time that early exposure to either high or lowest level Pb has long-term consequences on different synaptic properties of at least two hippocampal synapses. Such consequences of early Pb exposure might worsen the cognitive decline observed in aging men and women. Our results suggest that additional efforts should focus on the consequences of early Pb exposure especially in at-risk communities.
Project description:This study aimed to evaluate the protective role of Nigella sativa oil against the adverse effects of tartrazine on male rats. 18 albino rats were divided randomly into four groups (n?=?6). The first (G1) is the negative control, the second group (G2) is the positive control received 10?mg/kg b.w. tartrazine in the diet and the third (G3) received the same dose of tartrazine as in G2 and co-treated with Nigella sativa oil for 8 weeks. Tartrazine decreased total protein, antioxidants and high density lipoproteins, whereas increased liver enzyme, kidney function parameters, total cholesterol, triglycerides, low density lipoproteins and lipid peroxidation in the positive control group. In addition, it caused pathological changes in the tissues of liver, kidney, testes and stomach. Treating tartrazine supplemented rats of G3 with Nigella sativa oil for 8 weeks significantly improved all biochemical parameters and restored the tissues of kidney, stomach, testes and liver to normal. It could be concluded that N. sativa oil succeeded in protecting male rats against the adverse conditions resulted from tartrazine administration.
Project description:Nigella sativa Linn. (N. sativa) and its bioactive constituent Thymoquinone (TQ) have demonstrated numerous pharmacological attributes. In the present study, the neuroprotective properties of Thymoquinone-rich fraction (TQRF) and TQ against hydrogen peroxide- (H2O2-) induced neurotoxicity in differentiated human SH-SY5Y cells were investigated. TQRF was extracted using supercritical fluid extraction while TQ was acquired commercially, and their effects on H2O2 were evaluated using cell viability assay, reactive oxygen species (ROS) assay, morphological observation, and multiplex gene expression. Both TQRF and TQ protected the cells against H2O2 by preserving the mitochondrial metabolic enzymes, reducing intracellular ROS levels, preserving morphological architecture, and modulating the expression of genes related to antioxidants (SOD1, SOD2, and catalase) and signaling genes (p53, AKT1, ERK1/2, p38 MAPK, JNK, and NF-??). In conclusion, the enhanced efficacy of TQRF over TQ was likely due to the synergism of multiple constituents in TQRF. The efficacy of TQRF was better than that of TQ alone when equal concentrations of TQ in TQRF were compared. In addition, TQRF also showed comparable effects to TQ when the same concentrations were tested. These findings provide further support for the use of TQRF as an alternative to combat oxidative stress insults in neurodegenerative diseases.