Assessment of Cholinesterase inhibition activity of birds inhabiting pesticide exposed croplands and protected area in hot semi-arid region of Pakistan

Acetylcholinesterase (AChE) activity levels can be used as an indicator for AChE inhibition due to pesticide poisoning in bird species. We assessed the comparative brain cholinesterase (AChE) activity level of five bird species inhabiting pesticide exposed croplands and Protected Area i.e. Deva Vatala National Park (DVNP), Bhimber by using a spectrophotometric method. AChE activity levels ranged from 56.3 to 85.9 µmol/min/g of brain tissue of birds representing DVNP. However, AChE activity levels ranged from 27.6 to 79.9 µmol/min/g of brain tissue of birds representing croplands. AChE activity levels observed in Jungle babbler, Common babbler, and Red-vented bulbul showed significant differences (P < 0.05) at two sites. However, White wagtail and Black drongo demonstrated non-significant differences (P > 0.05). Maximum inhibition was recorded in Jungle babbler (53%) followed by Common babbler (35%), Red-vented bulbul (18%), White wagtail (15%), and Black drongo (7%). The brain cholinesterase inhibition levels under-protected ecosystems (DVNP, Bhimber) and agricultural landscape suggest insecticidal contamination and its impact on avifauna diversity. The study also emphasizes on the importance of pesticide-free zones to protect the biodiversity of birds.

Effect of grewia hirsuta vahl ethanolic root extract on cognition in scopolamine induced amnesia

Objective Alzheimer's illnesses are becoming medical nightmares because there is no exact solution and existing nootropic medicines (Piracetam, tacrine, and metrifonate) have significant drawbacks. The goal of this study was to see if the ethanolic root extract of Grewia hirsuta (ERGH) could improve memory in rats who had been given scopolamine. Materials and procedures At rats, ERGH was given orally in dosages of 200 and 400 mg/kg for 28 days, followed by Scopolamine (18 mg/kg i.p.) from the 25th to the 27th day. The usual nootropic drug was piracetam (200 mg/kg). The elevated plus maze (EPM), Morris water maze (MWM), and passive avoidance (PA) paradigms are used to assess cognitive functioning. Invivo anti-oxidant activity and brain acetylcholine esterase (AchE) activity were assessed. Results: At the indicated doses, ERGH extract showed a substantial memory-enhancing activity by decreasing the transfer latency in EPM, increasing the escape latency in MWM, and increasing the shock-free zone in PA. In scopolamine-induced amnesia rats, pretreatment with ERGH resulted in a significant drop in AchE enzyme, an increase in enzymatic antioxidant, and a decrease in MDA levels. Conclusion Because of its several favorable benefits, such as memory-improving properties, anticholinesterase activity, and antioxidant activity, ERGH may prove to be a useful drug in the current study, and it would be important to investigate its potential in the care of Alzheimer's patients.

Neuromodulatory Mechanisms оf a Memory Loss Preventive Effect of Alpha-Lipoic Acid in an Experimental Rat Model of Dementia

This study evaluates some of the neuromodulatory mechanisms of the memory loss preventive effect of alpha-lipoic acid (ALA) in a scopolamine (Sco)-induced rat model of an Alzheimer’s disease (AD) type dementia. Our results confirmed that Sco administration induces significant memory impairment, worsens exploratory behaviour and habituation; it increases acetylcholinesterase (AChE) activity and induces pathological monoamine content changes in the brain prefrontal cortex and hippocampus. ALA administration prevented to a large extent Sco-induced memory impairment; it also improved exploratory behaviour and preserved habituation; it decreased AChE activity, reversing it to Control group levels and corrected aberrant monoamine levels in the brain prefrontal cortex and hippocampus. According to the data available, this is the first time that ALA-induced changes in AChE and monoamine levels in the brain prefrontal cortex and hippocampus (brain structures related to learning and memory) have been demonstrated in a Sco-induced rat model of AD type dementia.

A Study on the Alleviating Effects of N-phthaloyl-γ-Aminobutyric Acid (P-GABA) on the Behavioral, Histopathological and Biochemical Adverse Effects of Sleep Deprivation in Zebrafish (Danio rerio)

Background: Sleep is defined as a reversible behavioural state of perceptual disconnection from insensitivity to the environment that facilitates the interaction of physiological and behavioural processes. Sleep Deprivation (S.D.) is defined as a decrease in sleeping duration below the recommended minimum, which has been linked to learning and memory problems. Aim: The primary objective of this work was to determine the effect of P-GABA on metabolic parameters, behavioural changes, whole-body cortisol, and brain histology in light-induced sleep-deprived zebrafish, as well as the optimal dose of P-GABA neutralizing undesirable effects. Methodology: The present study was conducted for ten days, consisting of three days in a row of sleep deprivation and seven days of treatment with P-GABA. The current investigation used six fishes in a group (n=6). Group 1: Control ; Group 2: 24h Total SD ; Group 3: 48h Total SD ; Group 4: 72h Total SD ; Group 5: 24h Total SD + P-GABA (100 mg/L) ; Group 6: 48h Total SD + P-GABA (100 mg/L) ;Group 7: 72h Total SD + P-GABA (100 mg/L) Results: The current study provides scientific data demonstrating the positive effects of P-GABA in treating sleep deprivation and associated cognitive impairment. To test if P-GABA treatment can alleviate the cognitive and memory impairment caused by S.D., we established non-toxic concentrations and treated the zebrafish with a safe dose of 100mg/L. The use of P-GABA increased cognitive performance in the T-maze, demonstrating that it has a favourable effect in a sleep-deprivation condition. The SD group exhibited neutrophil infiltration, and this S.D fish treated with P-GABA at a concentration of 100 mg/L demonstrated a moderate reduction in neuronal cell degeneration compared to controls. The levels of biochemical parameters during sleep deprivation and treatment phase with P-GABA were checked. It was evident from the results that the SOD, CAT and GPX levels in the S.D groups were drastically decreased, whereas treatment with P-GABA could show a significant increase in the levels of biochemical parameters. In contrast to the control group, zebrafish subjected to sleep deprivation showed enhanced AChE activity in the brain. The results of the P-GABA indicated an anti-AChE profile, which corresponds to improved memory parameters in zebrafish, as observed in the NTT and T-maze tests. When comparing the sleep-deprived fish to the control group, the MDA level, which indicates lipid peroxidation, was higher. Treatment with P-GABA considerably reduced the amount of MDA produced compared to the amount produced in sleep-deprived fish. The cortisol levels gradually increased in the single row 24h, 48h, and 72h sleep deprived groups. There was a gradual decrease in cortisol levels in the groups that received P-GABA treatment. The levels of neurotransmitters were seen to be decreased in the sleep-deprived groups when compared with the control. Upon treatment with P-GABA, the neurotransmitters were restored to near normal. Conclusion: This study showed that P-GABA counteracts cognitive performance decrease and anxiety increase resulting from sleep deprivation through a mechanism implying mitigation of brain oxidative stress and regulation of AChE activity.

Antioxidant Effects of Sophora davidi (Franch.) Skeels on d–Galactose–Induced Aging Model in Mice via Activating the SIRT1/p53 Pathway

This study investigated the protective effect of Sophora davidi (Franch.) Skeels fruits extract (SDE) on d–galactose–induced acute aging in mice. Ultra performance liquid chromatography coupled with tine-of-flight mass spectrometry (UPLC-Q-TOF/MS) was performed to identify the composition of compounds in SDE. KM mice were divided stochastically into the normal control group (NC, saline), d–galactose (D-gal) model group, vitamin C (Vc) group (positive control), low–, medium–and high–dose SDE treat groups. After 28 days administration and fasting overnight, the serum, liver, and brain samples of mice were collected. The levels of inducible nitric oxide synthase (iNOS), acetylcholinesterase (AChE) activity in the brain, malondialdehyde (MDA) and reduced glutathione (GSH) content, superoxide dismutase (SOD) and total antioxidant capacity (T–AOC) activity in the liver and brain were measured. Immunohistochemistry was applied to detect silent information regulator 1 (SIRT1) and p53 protein expression in the liver and brain, and quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of nuclear factor κB (NF–κB), tumor necrosis factor (TNF–α), interleukin–6 (IL–6), interleukin-1β (IL–1β), and anti-aging factor Klotho in the liver and brain. The results showed that UPLC-Q-TOF/MS identified 78 compounds in SDE. SDE could reduce the iNOS activity in serum and AChE activity in the brain, upregulate the levels of SOD, T–AOC and GSH in liver and brain, and debase the MDA content in liver and brain. SDE could downregulate the mRNA expressions of TNF–α, NF–kB, IL–1β, and IL–6 in the liver and brain, and elevate the mRNA expression of Klotho. SDE improved the pathological changes of the liver and brain induced by D–gal, increased the expression of SIRT1 protein in the liver and brain, and inhibited the expression of p53 protein induced by D–gal. To summarize, SDE demonstrated clear anti–aging effect, and its mechanism may be relevant to the activation of the SIRT1/p53 signal pathway.

Mitigation of Lead Neurotoxicity by Aqueous Fruit Extract of Adansonia digitata in Adult Wistar Rats

Aim: The current study seeks to explore the neuroprotective benefits of Adansonia digitata against lead induced memory impairment, neurotransmitter/AChE activity imbalance, oxidative stress as well as brain damage. Methodology: Thirty male adult rats weighing 160g-200g were divided randomly into six groups (I-V1) consisting of five (5) rats in each group. Group I served as control and were administered with distilled water (1 ml/kg) only while groups II -VI were treatment groups. Group II were administered 250 mg/kg of Adansonia digitata; group III were administered 30 mg/kg of lead; Group IV were administered 250 mg/kg of Adansonia digitata plus 30 mg/kg of lead; Group V were administered 500 mg/kg of Adansonia digitata plus 30 mg/kg of lead; Group VI were administered 30 mg/kg of lead plus 10 mg/kg of succimer. All administrations were carried out through oral gavage for a period of 28 days. Results: Lead administration caused memory impairment, decreased dopamine concentration and AChE activity in brain, induced oxidative stress resulting in brain damage. Adansonia digitata treatment significantly (P<.001) attenuated memory impairment, modulated dopamine concentration and AChE activity, prevented oxidative stress and ameliorated histopathological changes in the brain of Wistar rats. Conclusion: The result showed that Adansonia digitata ameliorates lead-induced memory impairment in Wistar rats by improving memory index, controlling dopamine concentration and AChE activity, preventing oxidative stress and neuronal degeneration.

Respiratory, Hepatic, Renal and Hematological Disorders Among Adolescent Females Environmentally Exposed To Pesticides, Menoufia Governorate, Egypt

Adolescent females are often environmentally exposed to pesticides by living near agricultural fields, by using pesticides at home, or by having contact with contaminated clothes and pesticide application work tools. This study assessed respiratory, hepatic, renal and hematological health disorders that might arise due to environmental exposure to pesticides among adolescent females. A cross-sectional study was conducted with 100 adolescent females environmentally exposed to pesticides who had one or more of their family members working as seasonal pesticides' applicators and 50 non- exposed (control) adolescent females from Menoufia governorate, Egypt. The studied period of pesticide application season of cotton crop was from May 1st to the end of September 2017. Participants completed a self-administered questionnaire about pesticide exposure and respiratory, hepatic, renal and hematological disorders. In addition, serum acetyl cholinesterase (AChE), spirometry, complete blood count, liver and kidney functions' tests were measured pre and post pesticide application season. The control adolescent females had a higher AChE activity, a lower prevalence of respiratory symptoms and higher means of spirometric measurements than the exposed group. During the pre and postseason, the exposed group presented a prevalence of (6%, 24%) for cough, (4%, 11%) for rhinitis, and (6%, 26%) for dyspnea during the pre and postseason; respectively. In addition, there was a decrease in means of spirometric measurements (FEV1%, FEV1/FVC%, FEF 25-75% and PEF%) in post season compared to preseason among the exposed group. Also, there were significant associations between (AChE) activity and both the prevalence of respiratory manifestations and spirometric measurements among the exposed females. On the other hand, there were significantly increased red blood corpuscles (RBCs) and lymphocytes counts, and a significantly lower mean hemoglobin level among the exposed group (post season) than each of their pre-season values and the control group (P<0.05). AChE level, total protein, albumin and albumin/globulin (A/G) ratio levels were significantly lower, while SGPT, SGOT, and globulin, blood urea and serum creatinine mean levels were significantly higher among the exposed group (post season) than either of their pre-season or the control group (P<0.05). There was a positive correlation between AChE level and all studied CBC parameters for the exposed group reaching a significant level with basophils (P<0.05). Also, there was a negative correlation between AChE level and each of SGPT, SGOT, ALP, globulin, blood urea and serum creatinine for the exposed group reaching a significant level with each of SGPT and SGOT (P<0.05). At the same time, a non-significant positive correlation was found between AChE level and each of total protein, albumin and A/G ratio (P>0.05). So, environmental exposure to organophosphorus pesticides has a detrimental impact on respiratory, hepatic, renal and hematological systems of adolescent females living in rural districts at Menoufia governorate. Educational and training intervention programs on pesticide handling and safety precautions are recommended for protecting both pesticides' workers and their family members who might be exposed.

Evaluation of different extraction techniques for the assay of anti - acetylcholinesterase activity of olive leaves (Olea europaea)

The total phenol content and the anti-acetylcholinesterase activity were compared in olive leaf (OL) extracts obtained using both subcritical water extraction (SbWE) and conventional solvent extraction (ethanol-water). The method proposed by Ellman (in vitro) was used to study the inhibitory activity of acetylcholinesterase (AChE). The total content of phenolic compounds and AChE activities of OL extracts varied depending on the used extraction method. Thus, the extract obtained using the subcritical water technique (220 °C) showed the highest amounts of total phenolic components, expressed as gallic acid equivalents, (70.4 mg/g raw material) and the highest inhibitory AChE-activity (IC50 = 0.35 mg/ml). The obtained values of the anti-AChE activity of the extracts of OL demonstrated that the inhibitory activity for SbW-extract 120 °C (IC50 = 2.92 mg/ml) and SbW-extract 180 °C (IC50 = 0.8 mg/ml) is higher than that of the traditional extract (IC50 = 3.6 mg/ml), respectively. These results indicate a great potential of the subcritical water technique to develop the techniques to produce commercial extracts of OL, and these results could encourage improved utilization of the OL. The collected data on the anti - acetylcholinesterase activity of olive leaves clearly demonstrate the prospects for use of OL extracts in the development of novel pharmaceutical substances and nutraceuticals for the prevention and/or the treatment of Alzheimer's disease as well as some other neurodegenerative diseases.

Association between human paraoxonase 2 protein and efficacy of acetylcholinesterase inhibiting drugs used against Alzheimer’s disease

Serum Paraoxonase 2 (PON2) level is a potential biomarker owing to its association with a number of pathophysiological conditions such as atherosclerosis and cardiovascular disease. Since cholinergic deficiency is closely linked with Alzheimer’s disease (AD) progression, acetylcholinesterase inhibitors (AChEIs) are the treatment of choice for patients with AD. However, there is a heterogenous response to these drugs and mostly the subjects do not respond to the treatment. Gene polymorphism, the simultaneous occurrence of two or more discontinuous alleles in a population, could be one of the important factors for this. Hence, we hypothesized that PON2 and its polymorphic forms may be hydrolyzing the AChEIs differently, and thus, different patients respond differently. To investigate this, two AChEIs, donepezil hydrochloride (DHC) and pyridostigmine bromide (PB), were selected. Human PON2 wildtype gene and four mutants, two catalytic sites, and two polymorphic sites were cloned, recombinantly expressed, and purified for in vitro analysis. Enzyme activity and AChE activity were measured to quantitate the amount of DHC and PB hydrolyzed by the wildtype and the mutant proteins. Herein, PON2 esterase activity and AChE inhibitor efficiency were found to be inversely related. A significant difference in enzyme activity of the catalytic site mutants was observed as compared to the wildtype, and subsequent AChE activity showed that esterase activity of PON2 is responsible for the hydrolysis of DHC and PB. Interestingly, PON2 polymorphic site mutants showed increased esterase activity; therefore, this could be the reason for the ineffectiveness of the drugs. Thus, our data suggested that the esterase activity of PON2 was mainly responsible for the hydrolysis of AChEI, DHC, and PB, and that might be responsible for the variation in individual response to AChEI therapy.

Neuroprotective effects of Huperzine-A in aluminum induced neurotoxicity in hippocampus of mice

Exposure to aluminum has been correlated with the epidemiology of Alzheimer’s disease. Huperzine A (HupA), derived from the Chinese herb Huperzia serrata, is an inhibitor of acetylcholinesterase (AChE). However, its use in aluminum induced neurotoxicity has not been reported. The objective of the study was to examine the effect of HupA on aluminum-induced changes in AChE activity and hippocampal neurotoxicity. Aged female swiss albino mice were divided into five groups (n=10). Aluminum treated group (Al-S) received 30 mg/Kg of aluminum chloride (AlCl3) intraperitoneally (IP) for two weeks followed by IP normal saline. Three HupA treated groups received similar IP dosage of AlCl3 for two weeks followed by HupA 0.1 mg/Kg, HupA 0.2 mg/Kg and HupA 0.5 mg/kg. Control group received IP normal saline. At the end of week 4, AChE was estimated, and pyramidal neurons of hippocampus were counted. Al-S group showed an increase in mean brain AChE and Al-HupA 0.1 reduced it significantly (p<0.05). Reduction in mean neuronal density in Al-S group, was comparatively more in CA3 hippocampal area (p<0.001). Quantitative study found that 0.2mg/Kg of synthetic Huperzine A given intraperitoneally, was able to increase neuronal count significantly compared to 0.1mg/Kg and 0.5mg/Kg of Huperzine A.