Biflavonoid quercetin protects against cyclophosphamide-induced organ toxicities via modulation of inflammatory cytokines, brain neurotransmitters, and astrocyte immunoreactivity

BACKGROUND

Cyclophosphamide use has been associated with increased oxidative stress in cells and tissues. Quercetin's antioxidative properties make it of potential benefit in such conditions of oxidative stress.

OBJECTIVE

To assess quercetin's ability to mitigate cyclophosphamide-induced organ toxicities in rats.

METHODS

Sixty rats were assigned into six groups. Groups A and D served as normal and cyclophosphamide control and were fed standard rat chow, groups B and E were fed quercetin supplemented diet (100 mg/kg of feed), while those in groups C and F were fed quercetin at 200 mg/kg of feed. Groups A-C received intraperitoneal (ip) normal saline on days 1 and 2, while D-F received ip cyclophosphamide (150 mg/kg/day on days 1 and 2). On day 21, behavioural tests were carried out, animals were sacrificed and blood samples taken. Organs were processed for histological study.

RESULTS

Quercetin reversed cyclophosphamide-induced decrease in body weight, food intake and total antioxidant capacity, and increase in lipid peroxidation (p = 0.001), It also reversed derangement in levels of liver transaminase, urea, creatinine and proinflammatory cytokines (p = 0.001). Improvement in working-memory and anxiety-related behaviours were also observed. Finally, quercetin reversed alterations in levels of acetylcholine, dopamine and brain-derived neurotropic factor (p = 0.021); while reducing serotonin levels and astrocyte immunoreactivity.

CONCLUSION

Quercetin shows significant ability to protect against cyclophosphamide-induced changes in rats.

Diabetes Mellitus and Energy Dysmetabolism in Alzheimer's Disease: Understanding the Relationships and Potential Therapeutic Targets

Over the last century, there has been a gradual but sustained increase in life expectancy globally. A consequence of increased life expectancy is an associated rise in the prevalence of agerelated chronic debilitating neurodegenerative disorders, such as Alzheimer's disease (AD), Parkinson's disease, Huntington's disease, and multiple sclerosis. These disorders, which are generally characterised by the loss of motor/sensory neurons and cognitive decline, have continued to confound researchers who are working tirelessly to define their pathogenetic mechanisms and develop effective therapies. In the last few years, there has been increasing evidence of the existence of a relationship between energy metabolism and neurodegeneration, with reports that type 2 diabetes mellitus increases the risk of AD. Evidence from preclinical and epidemiologic studies has associated dysmetabolism and dysmetabolic syndromes with the development of neurodegenerative changes. More recently, diabetes mellitus and energy dysmetabolism have been linked to the aetiopathogenesis of AD. Moreover, metabolic hormones, including ghrelin, leptin, insulin, and insulin-like growth factor (IGF)-1, have been reported to play key roles in the regulation of neuronal injury and loss in neurodegenerative diseases like AD. In this narrative review, we examine the current scientific evidence regarding the role of dysmetabolism (including diabetes mellitus and metabolic syndrome) in AD and how it impacts disease progression and the development of novel therapies in AD.

Prepubertal Continuous Dietary Folate Fortification Enhances the Brain Function of Adult Mice by Modulating Antioxidant Status, Inflammation, and Brain Neurotransmitter Levels

BACKGROUND

The benefits of folic acid supplementation have been documented in several studies. However, while evidence exists regarding its benefits for growth and haematologic parameters, its possible effects on the brain have been less examined.

OBJECTIVES

The study aimed to examine the benefits of dietary folic acid supplementation (beginning in the prepubertal period) on neurobehaviour, oxidative stress, inflammatory parameters, and neurotransmitter levels in adult mice.

METHODS

Forty-eight prepubertal male mice were assigned into four groups of 12 animals each. Mice were grouped into normal control (fed standard diet) and three groups fed folic acid supplemented diet at 2.5, 5, and 10 mg/kg of feed. Animals were fed a standard diet or folic acid-supplemented diet for eight weeks during which food intake and body weight were assessed. On postnatal day 78, animals were exposed to the open-field, Y-maze, radial arm maze, elevated plus maze, bar test, and models of behavioural despair. 24 hours after the last behavioural test, animals were made to fast overnight and then sacrificed by cervical dislocation. Blood was then taken for the assessment of blood glucose, leptin, and insulin levels. Homogenates of brain tissue were prepared and used for the assessment of biochemical parameters.

RESULTS

Results showed a concentration-dependent increase in body weight, and improved antioxidant status, memory scores, and acetylcholine levels. Also, a decrease in food intake, blood glucose, insulin, and leptin levels was observed. A reduction in open-field behaviour, anxiety-related behaviour, and proinflammatory markers, was also observed.

CONCLUSION

The beneficial effect of prepubertal continuous dietary folate fortification on the brain (as the animal ages) has been shown in this study.

Microbiome-Based Therapies in Parkinson's Disease: Can Tuning the Microbiota Become a Viable Therapeutic Strategy?

Progressive neurodegenerative disorders such as Parkinson's disease (PD) have continued to baffle medical science, despite strides in the understanding of their pathology. The inability of currently available therapies to halt disease progression is a testament to an incomplete understanding of pathways crucial to disease initiation, progression and management. Science has continued to link the activities and equilibrium of the gut microbiome to the health and proper functioning of brain neurons. They also continue to stir interest in the potential applications of technologies that may shift the balance of the gut microbiome towards achieving a favourable outcome in PD management. There have been suggestions that an improved understanding of the roles of the gut microbiota is likely to lead to the emergence of an era where their manipulation becomes a recognized strategy for PD management. This review examines the current state of our journey in the quest to understand how the gut microbiota can influence several aspects of PD. We highlight the relationship between the gut microbiome/microbiota and PD pathogenesis, as well as preclinical and clinical evidence evaluating the effect of postbiotics, probiotics and prebiotics in PD management. This is with a view to ascertaining if we are at the threshold of discovering the application of a usable tool in our quest for disease modifying therapies in PD.

Parkinson's Disease: Is there a Role for Dietary and Herbal Supplements?

Parkinson's Disease (PD) is characterised by degeneration of the neurons of the nigrostriatal dopaminergic pathway of the brain. The pharmacological cornerstone of PD management is mainly the use of dopamine precursors, dopamine receptor agonists, and agents that inhibit the biochemical degradation of dopamine. While these drugs initially provide relief to the symptoms and improve the quality of life of the patients, progression of the underlying pathological processes, such as oxidative stress and neuroinflammation (which have been strongly associated with PD and other neurodegenerative disorders), eventually reduce their benefits, making further benefits achievable, only at high doses due to which the magnitude and frequency of side-effects are amplified. Also, while it is becoming obvious that mainstream pharmacological agents may not always provide the much-needed answer, the question remains what succour can nature provide through dietary supplements, nutraceuticals and herbal remedies? This narrative review examines current literature for evidence of the possible roles (if any) of nutraceuticals, dietary supplements and herbal remedies in the prevention or management of PD by examining how these compounds could modulate key factors and pathways that are crucial to the pathogenesis and/or progression of PD. The likely limitations of this approach and its possible future roles in PD prevention and management are also considered.

Neuroinflammation and Oxidative Stress in Alzheimer's Disease; Can Nutraceuticals and Functional Foods Come to the Rescue?

Alzheimer's disease (AD), the most prevalent form of age-related dementia, is typified by progressive memory loss and spatial awareness with personality changes. The increasing socioeconomic burden associated with AD has made it a focus of extensive research. Ample scientific evidence supports the role of neuroinflammation and oxidative stress in AD pathophysiology, and there is increasing research into the possible role of anti-inflammatory and antioxidative agents as disease modifying therapies. While, the result of numerous preclinical studies has demonstrated the benefits of anti-inflammatory agents, these benefits however have not been replicated in clinical trials, necessitating a further search for more promising anti-inflammatory agents. Current understanding highlights the role of diet in the development of neuroinflammation and oxidative stress, as well as the importance of dietary interventions and lifestyle modifications in mitigating them. The current narrative review examines scientific literature for evidence of the roles (if any) of dietary components, nutraceuticals and functional foods in the prevention or management of AD. It also examines how diet/ dietary components could modulate oxidative stress/inflammatory mediators and pathways that are crucial to the pathogenesis and/or progression of AD.

Peripheral and Central Glutamate Dyshomeostasis in Neurodegenerative Disorders

Glutamate's role as the major excitatory neurotransmitter of the mammalian central nervous system requires that its brain concentrations be kept tightly-controlled. However, in hepatic encephalopathy resulting from liver dysfunction; disruption of central neurotransmission and elevation of brain glutamate levels have been observed. These had been associated with certain neurological changes. While neurological changes resulting from hepatic encephalopathy are believed to be transient, the discovery of alterations in liver enzymes in Alzheimer's disease and the role of glutamate and glutamate homeostasis in hepatic encephalopathy have piqued interests in the possible role of glutamate, and glutamate homeostasis in neurodegenerative diseases. Here, we discuss the evidence in support of the involvement of peripheral/central glutamate homeostasis in the development of neurodegenerative disorders, as well as, the implications of such interactions in the development of new therapies for neurodegenerative disorders.

Melatonin and Melatonergic Influence on Neuronal Transcription Factors: Implications for the Development of Novel Therapies for Neurodegenerative Disorders

Melatonin is a multifunctional signalling molecule that is secreted by the mammalian pineal gland, and also found in a number of organisms including plants and bacteria. Research has continued to uncover an ever-increasing number of processes in which melatonin is known to play crucial roles in mammals. Amongst these functions is its contribution to cell multiplication, differentiation and survival in the brain. Experimental studies show that melatonin can achieve these functions by influencing transcription factors which control neuronal and glial gene expression. Since neuronal survival and differentiation are processes that are important determinants of the pathogenesis, course and outcome of neurodegenerative disorders; the known and potential influences of melatonin on neuronal and glial transcription factors are worthy of constant examination. In this review, relevant scientific literature on the role of melatonin in preventing or altering the course and outcome of neurodegenerative disorders, by focusing on melatonin's influence on transcription factors is examined. A number of transcription factors whose functions can be influenced by melatonin in neurodegenerative disease models have also been highlighted. Finally, the therapeutic implications of melatonin's influences have also been discussed and the potential limitations to its applications have been highlighted.

Anti-inflammatory, anti-oxidant and anti-lipaemic effects of daily dietary coenzyme-Q10 supplement in a mouse model of metabolic syndrome

BACKGROUND

The dietary model of metabolic syndrome has continued to aid our understanding of its pathogenesis and possible management interventions. However, despite progress in research, therapy continues to be challenging in humans; hence, the search for newer treatment and prevention options.

OBJECTIVE

To evaluate the impact of dietary CQ₁₀ supplementation on metabolic, oxidative and inflammatory markers in a diet-induced mouse model of metabolic syndrome.

METHODS

Mouse groups were fed standard diet (SD), high-fat high-sugar (HFHS) diet, and SD or HFHS diet (with incorporated CQ₁₀) at 60 and 120 mg/kg of feed respectively. At the completion of the study (8 weeks), blood glucose levels, superoxide dismutase (SOD) activity, plasma insulin, leptin, adiponectin, TNF-α, IL-10, serum lipid profile, and lipid peroxidation (LPO) levels were assessed. The liver was either homogenised for the assessment of antioxidant status or processed for general histology.

RESULTS

Dietary CQ₁₀ mitigated HFHS diet-induced weight gain, decreased glucose, insulin and leptin levels; and increased adiponectin levels in mice. Coenzyme-Q₁₀ improved the antioxidant status of the liver and blood in HFHS diet fed mice, while also decreasing lipid peroxidation. Lipid profile improved, level of TNF-α decreased and IL-10 increased following CQ₁₀ diet. A mitigation of HFHS diet-induced alteration in liver morphology was also observed with CQ₁₀.

CONCLUSION

Dietary CQ₁₀ supplementation mitigates HFHS diet-induced changes in mice possibly through its anti-oxidant, anti-lipaemic and anti-inflammatory potential.

Concentration-dependent Effects of Dietary L-Ascorbic Acid Fortification in the Brains of Healthy Mice

BACKGROUND

Ascorbic acid (AA) is a water-soluble vitamin that is concentrated in the brain in large quantities. There have been reports that it is essential for proper brain functioning. However, there is insufficient information on the possible effects of dietary fortification with AA on the health of the brain.

OBJECTIVE

This study examined the effects of dietary fortification of rodent chow with AA on neurobehaviour, antioxidant status, lipid peroxidation, and inflammatory/apoptotic markers in the brain of healthy mice.

METHODS

Mice were randomly assigned into four groups of ten animals each. Groups were normal control [fed rodent chow], and three groups were fed AA-fortified chow at 100, 200, and 300 mg/kg of feed, respectively, for eight weeks. Behavioural tests {Open field, Y-maze, radial-arm maze, and elevated plus maze (EPM)} were carried out on day 57. Twenty-four hours after the last behavioural test, animals were euthanised, and the brains were excised and homogenised for assessment of brain acetylcholinesterase activity, lipid peroxidation, antioxidant status, inflammatory and apoptotic markers.

RESULTS

Ascorbic acid fortified diet was associated with concentration-dependent changes in body weight, open-field behaviours, working-memory, and anxiety indices. Also, brain levels of malondialdehyde, caspase-3, and TNF-α decreased, while superoxide dismutase activity, total antioxidant capacity, and IL-10 level increased.

CONCLUSION

Dietary AA fortification with concentrations up to 300 mg/kg of feed was associated with sustained improvement in neurobehavioural and biochemical parameters in the brain of healthy mice, reiterating additional health benefits of AA fortification beyond the prevention of nutritional deficiencies.

Evaluation of the Behavioural, Antioxidative and Histomorphological Effects of Folic Acid-supplemented Diet in Dexamethasone-induced Depression in Mice

BACKGROUND

The effect of folic acid in mitigating depression has remained pivotal in research.

OBJECTIVE

To determine the effects of folate supplementation on neurobehaviour oxidative stress and cerebral cortex histomorphology in the dexamethasone mouse model of depression.

METHODS

Male mice were assigned to six groups (A-F) of 10 mice each. Animals in groups A and D were fed a standard diet, while those in B and E were fed folic acid supplemented diet (25 mg/kg of feed), while C and F were fed folate supplemented diet at 50 mg/kg of feed for 8 weeks. At the beginning of the sixth 6th week, mice in groups A-C were administered distilled water, while animals in groups D-F were administered dexamethasone (DEX) at 4 mg/kg body weight by gavage. Open-field, forced swim, and tail-suspension tests were conducted at the end of the experimental period, following which animals were euthanised and blood was taken for the estimation of Malondialdehyde (MDA), reduced Glutathione, Glutathione Peroxidase, Catalase activity, and Superoxide Dismutase. Sections of the cerebral cortex were prepared for histological examination.

RESULTS

Folic acid supplementation increased body weight, locomotor, rearing and self-grooming behaviours, and decreased immobility time in the tail suspension and forced swim tests. There was also a reduction of lipid peroxidation and an increase in the antioxidant status. Folic acid supplementation was also found to be protective against the development of dexamethasone-induced changes in body weight, open-field behaviours, behavioural despair, oxidative stress and cerebrocortical morphology.

CONCLUSION

Folic-acid supplementation improves the behavioral, some antioxidant, and cerebral morphological parameters.

An Evaluation of the Effects of Pyridoxal Phosphate in Chlorpromazineinduced Parkinsonism using Mice

BACKGROUND

Parkinsonism is a neurodegenerative disorder with a heavy disease burden, despite the discovery and application of drugs. Current research is beginning to suggest the possible crucial roles of micronutrients such as pyridoxal phosphate in the prevention or management of neurodegenerative disorders.

OBJECTIVE

We investigated the possible protective effects of supplemental pyridoxal phosphate in Chlorpromazine (CPZ)-induced Parkinsonism-like changes in mice.

METHODS

Mice were assigned to eight groups of 30 mice each. Groups included Vehicle control (fed standard diet (SD), and administered intraperitoneal {ip} injection of saline and saline per orem), levodopa-carbidopa (LD) group (SD, saline ip and LD per orem), two groups fed pyridoxal phosphate-supplemented diet (at 100 and 200 mg/kg of feed), and administered saline both ip and orally, CPZ group (SD, CPZ ip and saline per orem), CPZ/LD group (SD, CPZ ip and LD per orem) and finally two groups fed pyridoxal phosphate -supplemented diet (at 100 and 200 mg/kg of feed) and administered CPZ ip plus saline per orem. Treatments were administered daily for a period of 21 days to allow for the induction of Parkinsonism features. Body weight and food intake were measured weekly while neurobehavioural and biochemical tests were assessed at the end of the experimental period.

RESULTS

Pyridoxal phosphate supplementation was associated with a reduction in CPZ-induced suppression of open-field horizontal locomotion and rearing; and a significant increase in grooming activity. Administration of pyridoxal phosphate-supplemented diet was also associated with improvements in working-memory in CPZ-treated mice; and there was reduction in the index of anxiety and catalepsy score.

CONCLUSION

Pyridoxal phosphate supplementation was associated with significant benefits in CPZ-induced Parkinsonism-like changes in mice.

Prevalence of Multi-Drug Resistant Tuberculosis among Tuberculosis Patients Attending Chest Clinics in Osun-State, Nigeria

BACKGROUND

The development of multidrug-resistant tuberculosis (MDR-TB) poses a considerable threat to tuberculosis control programmes in Nigeria. There is an increase in the prevalence of MDR-TB worldwide both among new tuberculosis cases as well as previously-treated ones. There is also a rise in transmission of resistant strains due to an increase in MDR-TB patients largely due to the poor drug compliance and the impact of Human immunodeficiency virus infection. Therefore, we intend to determine the extent of MDR-TB among attendees of chest clinics in Osun-State, Nigeria.

OBJECTIVES

The objective of this study was to determine the prevalence of MDR-TB among confirmed tuberculosis patients attending chest clinics in Osun-State, Nigeria.

METHODS

This study was conducted among 207 attendees of chest clinics in Osun-State between June, 2015 and October 15, 2016. Sputum and blood samples of the participants were collected. GeneXpert test was carried out first on the samples for simultaneous identification of MTB and rifampicin resistance. Sputum samples were cultured on Lowenstein-Jensen (L-J) medium using N-acetyl-Lcysteine- sodium hydroxide (NALC-NaOH) decontamination method. Drug susceptibility testing (DST) to three first-line drugs was carried out using the proportion DST method.

RESULTS

The prevalence of MTB was found to be 27.5% while the prevalence of MDR-TB from the fifty-seven isolates was 10.5%. Previously treated and new cases had a prevalence of 7.0% and 3.5% MDR-TB, respectively. Seventy (33.8%) participants were positive for HIV infection, out of which twenty-six (12.6%) had co-infection of tuberculosis and HIV. The mono-resistance rates of the three first-line drugs used were: 5.3% and 8.7% for ethambutol (EMB) and isoniazid (INH), respectively. No isolate had mono-resistance (0%) to rifampicin (RIF).

CONCLUSION

This study observed the prevalence of 27.5% MTB and a prevalence of 10.5% MDR-TB among the MTB isolates. The prevalence of TB is high in Osun State. MDR-TB prevalence is higher compared with the national estimate of MDR-TB (5.1%) of 2017. Resistant TB is a threat to national tuberculosis control and it is recommended that all the facilities be equipped to cater to its diagnosis.

Lepidium meyenii Supplemented Diet Modulates Neurobehavioral and Biochemical Parameters in Mice Fed High-Fat High-Sugar Diet

BACKGROUND

Metabolic syndrome has been associated with an increased risk of cardiovascular disease, diabetes mellitus, and neurodegenerative disorders. Known side-effects of currently- available drugs necessitate the search for possibly better treatment options.

OBJECTIVE

This study examined the effects of dietary lepidium meyenii (MACA) supplementation on neurobehaviour, metabolic profile, levels of inflammatory markers, and oxidative stress parameters in a mouse model of metabolic syndrome.

METHODS

Mice were randomly assigned into 8 groups of ten animals each. Groups consist of standard diet (SD) control, high fat/high sugar (HFHS) control and three groups each of lepidium meyenii incorporated into either SD or HFHS diet at 0.1, 0.2 and 0.4%. Mice were fed for seven weeks, and body weight was measured weekly. Open-field behaviors and radial-arm/Y-maze spatial memory were scored at the end of the study. Twenty-four hours after the last behavioral test, fasting blood glucose levels were estimated. Animals were then euthanized, and blood was drawn for estimation of serum lipid profile. Whole brains were excised, weighed and homogenized to estimate the levels of lipid peroxidation, inflammatory markers, antioxidant status, and acetylcholinesterase activity.

RESULTS

MACA-supplemented diet was associated with a decrease in body weight gain, an increase in food intake (at lower concentrations), suppression of grooming behavior, and decrease in acetylcholinesterase activity. MACA-supplement also reversed HFHS-induced memory impairment, anxiety, hyperglycaemia, lipid derangement, oxidative stress, and derangement of inflammatory markers.

CONCLUSION

Dietary supplementation with MACA shows beneficial effects in mitigating the effects of metabolic syndrome on the brain in mice.

Food-added azodicarbonamide alters haematogical parameters, antioxidant status and biochemical/histomorphological indices of liver and kidney injury in rats

OBJECTIVES

Azodicarbonamide (ADA) is a dough enhancer currently used as a replacement for potassium bromate in the process of bread-making in countries such as Nigeria. However, comprehensive information on the toxicological profile of ADA is not readily available. The present study investigated the toxicological effects of ADA in rats.

METHODS

Twenty-four adult rats were randomly assigned into four groups of six rats each. Animals in group A served as the control (administered standard diet), whereas animals in groups B, C and D were fed ADA in food at 1, 2 and 4%, respectively. Standard or ADA diet was fed to the animals daily for a period of 28 days. Body weight was measured weekly, whereas food and water consumption was measured daily. On day 28, animals were fasted overnight after which they were euthanised. Blood samples taken were used for assessment of fasting blood glucose, haematological parameters, serum lipids, antioxidant status, lipid peroxidation status, electrolytes and urea, plasma proteins and biochemical parameters of liver and kidney injury. The liver and kidneys were then excised and processed for general histological study.

RESULTS

The results showed that repeated administration of ADA was associated with dose-related decrease in weight gain, decrease in overall food consumption, decreased superoxide dismutase activity/glutathione level and increased lipid peroxidation. There was also biochemical and morphological evidence of liver and kidney injury.

CONCLUSIONS

These findings suggest that food-added ADA could be injurious to the body cells and organs in rats.

Dietary glutamate and the brain: In the footprints of a Jekyll and Hyde molecule

Glutamate is a crucial neurotransmitter of the mammalian central nervous system, a molecular component of our diet, and a popular food-additive. However, for decades, concerns have been raised about the issue of glutamate's safety as a food additive; especially, with regards to its ability (or otherwise) to cross the blood-brain barrier, cause excitotoxicity, or lead to neuron death. Results of animal studies following glutamate administration via different routes suggest that an array of effects can be observed. While some of the changes appear deleterious, some are not fully-understood, and the impact of others might even be beneficial. These observations suggest that with regards to the mammalian brain, exogenous glutamate might exert a double-sided effect, and in essence be a two-faced molecule whose effects may be dependent on several factors. This review draws from the research experiences of the authors and other researchers regarding the effects of exogenous glutamate on the brain of rodents. We also highlight the possible implications of such effects on the brain, in health and disease. Finally, we deduce that beyond the culinary effects of exogenous glutamate, there is the possibility of a beneficial role in the understanding and management of brain disorders.

Multidrug-Resistance Genes in Pseudomonas aeruginosa from Wound Infections in a Tertiary Health Institution in Osogbo, Nigeria

BACKGROUND

Multidrug Resistant Pseudomonas aeruginosa (MDRPA) is a ubiquitous opportunistic organism that poses threat to the management of infections globally.

OBJECTIVES

The objectives of the current research were to assess the antibiotic resistance profiles as well as Multiple Antibiotic Resistance (MAR) Index of clinical isolates of P. aeruginosa associated with wound infections. Presence of Extended Spectrum Beta Lactamase genes (bla CTX-M, bla SHV and bla TEM) and Carbapenemase genes (bla KPC and blaNDM) were also determined among the isolates.

METHODS

Swab samples were collected from 255 patients with wound infections. Bacterial identification was done by standard diagnostic tests. The identity of isolates was confirmed by the detection of the exoA gene using the PCR technique. Antibiotic susceptibility testing and resistance profile were determined using the disc diffusion method. Resistance genes were amplified by the PCR method.

RESULTS

A total of 235 (92.2%) bacterial isolates were recovered from the wounds of the 255 patients, of these, 124 (52.8%) were Gram-negative bacilli while the remaining 111 (47.2%) were Gram-positive cocci. A total of 69 Pseudomonas aeruginosa strains were recovered from the wound specimens. Imipenem was the most effective antibiotic against these isolates (92.8% isolates were susceptible) while all isolates were resistant to Meropenem, Cefepime, Ticarcillin, Amoxicillin-clavulanic acid, Cefotaxime, Ampicillin and Cefpodoxime. All 69 Pseudomonas aeruginosa isolates were multidrug resistant (MDR). Of the isolates selected for PCR, all were positive for TEM, CTX-M and SHV genes while one-third were blaKPC and blaNDM producers.

CONCLUSION

This study demonstrated high prevalence of carbapenem-resistant strains of P. aeruginosa, suggesting that there is an urgent need in Nigeria for the enactment and enforcement of policies and necessary laws restricting the availability and indiscriminate use of antibiotics.

African Plants with Antidiabetic Potentials: Beyond Glycaemic Control to Central Nervous System Benefits

BACKGROUND

For centuries, humans have used medicinal plants in the management of both acute and chronic diseases. Currently, the practice of using medicinal plants to manage diseases is becoming increasingly-common; especially in medium to low-income economies where the cost of, or ease of access to orthodox medications are limitations to their effective and sustained use. Diabetes mellitus is a chronic disease whose prevalence continues to increase worldwide. An aspect of diabetes mellitus that causes significant morbidity is its neurological complications, which are known to be associated with an enormous economic burden and reduction in quality of life.

OBJECTIVES

While research continues to demonstrate that a wide range of plants that are indigenous to Africa have significant antihyperglycaemic properties, scientific information on the neurobehavioural and/or neuromorphological effects of these plants appear to be lacking. Also, their possible benefits in the prevention or amelioration of the neurological complications of diabetes mellitus remain generally unexamined.

METHODOLOGY

In this narrative review, we the examine available scientific literature dealing with the neurobehavioural and/or neuromorphological profiles of selected African plants with substantiated antihyperglycaemic properties; aiming to highlight their potential applications in the prevention and management of the neurological complications of diabetes mellitus.

RESULTS

This review demonstrates that a number of the African plants with antidiabetic properties also exhibit central nervous system effects.

CONCLUSION

While the neurobehavioural and neuromorphological effects of some of these plants had been investigated in animal models of DM; their possible roles in the prevention or amelioration of the neurological complications of DM are yet to be established.

An Assessment of the Effects of Azodicarbonamide-containing Diet on Neurobehaviour, Brain Antioxidant Status and Membrane Lipid Peroxidation Status in Rats

BACKGROUND

Azodicarbonamide is a dough-enhancer used in the process of breadmaking in countries like Nigeria. While there have been suggestions that it is a sensitizer of the respiratory system, there is a dearth of information on its effects on the central nervous system.

AIM

This study assessed the effects of azodicarbonamide on the central nervous system (ADA) in rats.

OBJECTIVE

The effects of ADA-containing diet on neurobehaviour, brain antioxidant status, and neuromorphology of selected brain regions in rats were examined.

METHODS

Forty adult rats were randomly-assigned into four groups of ten rats each, and were given standard diet or diet containing ADA at 1, 2 and 4% respectively. Rats were fed a standard diet or ADA-containing diet for a period of 28 days. Weekly body weight assessment and daily estimation of food intake were done. Behavioural tests {in the Open field, Y-maze, radial-arm maze, and Elevated Plus Maze (EPM)} were conducted on day 29. Twenty-four hours after the last behavioural test, animals were euthanised, whole brains were dissected, weighed, and either homogenised for assessment of lipid peroxidation and antioxidant status; or sectioned and processed for general histology.

RESULTS

Consumption of ADA-containing diet was associated with a significant decrease in weight gain/food intake, and significant suppression of horizontal locomotion and rearing behaviours; however, grooming activity increased significantly. Also, there was a significant reduction of open-arm time in the EPM and a significant increase in Y-maze alternation (at the lowest concentration of ADA). ADA-containing diet was not associated with significant changes in brain oxidative status or neuromorphology.

CONCLUSION

The study showed that while ADA-containing diet may alter neurobehaviour in rats; this was not associated with evidence of brain oxidative stress or neuro-histomorphological alterations.

An Investigation of the Anti-Parkinsonism Potential of Co-enzyme Q10 and Co-enzyme Q10 /Levodopa-carbidopa Combination in Mice

BACKGROUND

Despite decades of research, neurodegenerative disorders like Parkinson's disease remain a leading cause of disability worldwide, due to the insufficient reduction of disease burden by available medications. Recently, the benefits of dietary supplements like co-enzyme Q₁₀ in neurodegenerative diseases have been reported. ; Aim: The protective effects of supplemental co-enzyme Q₁₀ (CQ₁₀) and possible additive benefits of CQ ₁₀/Levodopa-Carbidopa (LD) in Chlorpromazine (CPZ)-induced Parkinsonism-like changes in mice were investigated. ; Methods: Male mice were assigned to ten groups of 30 mice each. Groups included: Vehicle control (fed Standard Diet (SD), and given intraperitoneal {ip} plus oral saline), LD group (fed SD, and given ip saline plus oral LD), two groups fed CQ₁₀-supplemented diet (at 60 and 120 mg/kg of feed), and given ip plus oral saline, CPZ group (fed SD, and given ip CPZ plus oral saline), CPZ/LD group (fed SD, and given ip CPZ plus oral LD), two groups fed CQ₁₀-supplemented diet (at 60 and 120 mg/kg of feed) and given ip CPZ plus oral saline, and another two groups fed CQ₁₀-supplemented diet (at 60 and 120 mg/kg of feed) and given ip CPZ plus oral LD. The total duration of study was 21 days, and treatments were administered daily. Bodyweight and food intake were measured weekly, while neurobehavioural and biochemical tests were assessed at the end of the experimental period. ; Results: CQ₁₀-supplementation was protective against CPZ-induced parkinsonism-like changes including, reduction in mortality, the reversal of retardation of open-field behaviours and reduction of catalepsy, increase in dopamine levels and decreased oxidative stress. CQ₁₀ also showed significant improvements in these parameters when co-administered with LD. CQ₁₀ (in groups administered CPZ/CQ₁₀ 60) showed greater benefit over LD on anxiety-related behaviours and also had additive benefits on working-memory. ; Conclusion: Dietary CQ₁₀-supplementation was associated with demonstrable benefits in CPZinduced Parkinsonism-like changes in mice.

High Dietary Fat Modulates Neurobehavioural Effect of Lopinavir/ Ritonavir in Mice

BACKGROUND

Lopinavir/Ritonavir (LR) is a protease inhibitor used human immunodeficiency virus infection management. There have been issues regarding the effects of fat on LR efficacy and the possibility of neurological deficits following prolonged use, there is however a dearth of research examining this.

AIMS

The effects of LR administered with normal or High-Fat Diet (HFD) on neurobehaviour, neurochemistry and oxidative stress in healthy mice were examined.

METHODS

Mice were randomly-assigned into eight groups of ten (n=10) animals each. The groups were normal control [Standard Diet, (SD)], HFD control, 3 groups of LR incorporated into SD (100/25, 200/50 and 400/100 mg/kg of feed), and 3 groups of LR with HFD (100/25, 200/50 and 400/100 mg/kg of feed). Mice were fed daily for six weeks, following which open field, elevated-plus maze (EPM), radial-arm maze and Y-maze behaviours were scored. Twenty-four hours after tests, mice were euthanised and brains were homogenised for estimation of oxidative stress, L-glutamate level and acetylcholinesterase activity.

RESULTS

LR was associated with a reduction in HFD-induced weight gain, suppression of open-field behaviours with SD, and counteraction of HFD-induced changes in working-memory, open-field and anxiety-related behaviours. Also, LR causes increased lipid peroxidation and superoxide dismutase activity; and a decrease in brain glutamate, irrespective of dietary composition. Increased fat catabolism leading to increased oxidative stress could possibly account for the weight changes, while a decrease in brain glutamate could account for the changes in open-field behaviours in mice fed SD.

CONCLUSION

LR alters neurobehaviour, oxidative stress and brain glutamate in mice; however, only its effects on neurobehaviour are affected by diet.

Subchronic ketamine alters behaviour, metabolic indices and brain morphology in adolescent rats: Involvement of oxidative stress, glutamate toxicity and caspase-3-mediated apoptosis

Ketamine is a dissociative anaesthetic agent whose recreational use amongst adolescents and young adults is reaching epidemic proportions in a number of countries. While animal studies have examined the long-term detrimental effects of early-life ketamine exposure, there is a paucity of information on the immediate effects of ketamine following subchronic administration in the adolescence period. Adolescent rats were assigned into four groups of 10 animals each, administered intraperitoneal (i.p) injections of vehicle or one of three doses of ketamine (7.5, 15 or 30 mg/kg daily) for 8 weeks, and then exposed to behavioural paradigms. Rats were then euthanised after an overnight fast, and blood taken was used for measurement of metabolic indices. The brains were dissected out and either homogenised for estimation of neurochemical parameters, or processed for histological and immunohistochemical studies. Results showed that subchronic administration of ketamine was associated with a lesser weight gain inspite of an increase in food intake across the treatment groups. There was a dose-dependent increase in open-field novelty-induced behaviours, a decline in spatial working-memory, and an anxiolytic effect in the elevated-plus maze. There was associated derangement of serum triglyceride, and increase in brain glutamate levels, acetylcholinesterase activity, plasma/brain oxidative stress parameters, caspase-3 activity and biochemical indices of hepatic and renal function. Ketamine administration was also associated with neurodegenerative changes in the cerebral cortex, hippocampus, cerebellum and the pons. In conclusion, subchronic administration of ketamine to adolescent rats was associated with dose-related memory loss, oxidative stress and possibly caspase-3 mediated neurodegenerative changes.

Melatonin, adolescence, and the brain: An insight into the period-specific influences of a multifunctional signaling molecule

Melatonin is a neurohormone that is involved in the modulation of a wide range of physiological processes, including maintenance of the circadian rhythm, mediation of photoperiodic information, regulation of the sleep-wake cycle, synchronization of cell physiology, antioxidant defense, and immune-modulation. Although there are reports of increasing use of melatonin in the management of a number of health conditions, evidence exists that is suggestive of deleterious effects of melatonin administration on brain and reproductive development in the prepubertal and pubertal periods that are within the teenage years. In this review, we examine the influences of endogenous and exogenous melatonin on the adolescent brain, with specific reference to its involvement in the evolution of brain functions, brain structure, sleep regulation, and modulation of behaviors in health or disease.

Circadian dysrhythmia-linked diabetes mellitus: Examining melatonin’s roles in prophylaxis and management

Diabetes mellitus is a chronic, life-threatening metabolic disorder that occurs worldwide. Despite an increase in the knowledge of the risk factors that are associated with diabetes mellitus, its worldwide prevalence has continued to rise; thus, necessitating more research into its aetiology. Recent researches are beginning to link a dysregulation of the circadian rhythm to impairment of intermediary metabolism; with evidences that circadian rhythm dysfunction might play an important role in the aetiology, course or prognosis of some cases of diabetes mellitus. These evidences thereby suggest possible relationships between the circadian rhythm regulator melatonin, and diabetes mellitus. In this review, we discuss the roles of the circadian rhythm in the regulation of the metabolism of carbohydrates and other macronutrients; with emphasis on the importance of melatonin and the impacts of its deficiency on carbohydrate homeostasis. Also, the possibility of using melatonin and its analogs for the “prophylaxis” or management of diabetes mellitus is also considered.

Melatonin in drug addiction and addiction management: Exploring an evolving multidimensional relationship

Melatonin is a pleiotropic signalling molecule that regulates several physiological functions, and synchronises biological rhythms. Recent evidences are beginning to reveal that a dysregulation of endogenous melatonin rhythm or action may play a larger role in the aetiology and behavioural expression of drug addiction, than was previously considered. Also, the findings from a number of animal studies suggest that exogenous melatonin supplementation and therapeutic manipulation of melatonin/melatonin receptor interactions may be beneficial in the management of behavioural manifestations of drug addiction. However, repeated exogenous melatonin administration may cause a disruption of its endogenous rhythm and be associated with potential drawbacks that might limit its usefulness. In this review, we examine the roles of melatonin and its receptors in addictive behaviours; discussing how our understanding of melatonin’s modulatory effects on the brain rewards system and crucial neurotransmitters such as dopamine has evolved over the years. Possible indications(s) for melatonergic agents in addiction management, and how manipulations of the endogenous melatonin system may be of benefit are also discussed. Finally, the potential impediments to application of melatonin in the management of addictive behaviours are considered.

Correction to: Comparative effects of sertraline, haloperidol or olanzapine treatments on ketamine-induced changes in mouse behaviours

In the original publication of the article, occurrences of "{F(Becker and Grecksch 2004; Onaolapo et al. 2016b)" should have been "{F(5, 54)" throughout the article.

Cyclophosphamide-induced male subfertility in mice: An assessment of the potential benefits of Maca supplement

Effects of Lepidium meyenii (Maca) on cyclophosphamide (CYP)-induced gonadal toxicity in male mice were investigated. Mice were assigned to six treatment groups: Vehicle control, CYP control, CYP plus oral Maca (500 or 1,000 mg/kg), and oral Maca (500 or 1,000 mg/kg). CYP was administered via the intraperitoneal route (days 1-2), while vehicle or Maca were administered daily for 28 days. On day 28, half of the animals in each group were either sacrificed or paired with age-matched females for fertility assessment. Plasma testosterone assay, sperm analysis and assessment of tissue antioxidant/morphological status were also carried out. CYP administration was associated with oxidative stress, subfertility and morphometric/morphological indices of gonadal injury, while administration of Maca mitigated CYP-induced gonadal toxicity and subfertility. This study shows that Maca is beneficial in the mitigation of CYP-induced male gonadal insufficiency and/or testicular morphological changes; however, further studies will be needed to ascertain its usability for this purpose in humans.

Comparative effects of sertraline, haloperidol or olanzapine treatments on ketamine-induced changes in mouse behaviours

Effects of sertraline, haloperidol or olanzapine administration on ketamine-induced behaviours in mice were examined. The aim was to ascertain the degree of reversal of such behaviours by sertraline, and compare its effectiveness to haloperidol and olanzapine. Ten-week old mice (N = 120) were equally divided into main groups; 1 (open-field, radial-arm maze and elevated plus maze {EPM} tests), and 2 (social interaction test). Mice in each main group were assigned into six groups of ten (n = 10) each. Group 1 received intraperitoneal (i.p) injection of vehicle, while groups 2-6 received i.p ketamine at 15 mg/kg daily for 10 days. From day 11 to 24, mice in group 1 (vehicle) were given distilled water (i.p at 2 ml/kg and oral at 10 ml/kg), group 2 (ketamine control) received daily i.p ketamine and oral distilled water; while animals in groups 3-6 received daily i.p. ketamine and oral haloperidol (4 mg/kg), olanzapine (2 mg/kg), or one of two doses of sertraline (SERT) (2.5 or 5 mg/kg), respectively. Treatments were administered daily, and behaviours assessed on days 11 and 24. Results showed that repeated ketamine administration caused hyperlocomotion, increased self-grooming, memory loss and social withdrawal. Administration of sertraline (both doses), haloperidol, and olanzapine reversed ketamine-induced behavioural changes. However, in the EPM, sertraline and olanzapine were anxiolytic, while haloperidol was anxiogenic. Sertraline's effect on behaviours tested was comparable to olanzapine and better than haloperidol. In conclusion, this study shows that sertraline's ability to counteract ketamine-induced behavioural changes in mice is comparable to known antipsychotics.

Melatonin attenuates behavioural deficits and reduces brain oxidative stress in a rodent model of schizophrenia

Melatonin is a neurohormone that is linked to the aetiopathogenesis of schizophrenia. The aim of this study was to assess the potentials of oral melatonin supplement in the management of induced schizophrenia-like behavioural and brain oxidative status changes, using an animal model. The relative degrees of modulation of ketamine-induced behaviours by haloperidol, olanzapine or melatonin were assessed in the open-field, Y-maze, elevated plus maze and the social interaction tests. 12-week old, male mice were assigned to six groups of ten each (n=10). They were pretreated with daily intraperitoneal ketamine at 15mg/kg (except vehicle) for 10days, before commencement of 14day treatment with standard drug (haloperidol or olanzapine) or melatonin. Ketamine injection also continued alongside melatonin or standard drugs administration for the duration of treatment. Melatonin, haloperidol and olanzapine were administered by gavage. Treatments were given daily, and behaviours assessed on days 11 and 24. On day 24, animals were sacrificed and whole brain homogenates used for the estimation of glutathione, nitric oxide and malondialdehyde levels. Ketamine injection increased open-field behaviours; while it decreased working-memory, social-interaction and glutathione activity. Nitric oxide and malondialdehyde levels also increased after ketamine injection. Administration of melatonin was associated with variable degrees of reversal of these effects. In conclusion, melatonin may have the potential of a possible therapeutic agent and/or adjunct in the management of schizophrenia.

Alterations in behaviour, cerebral cortical morphology and cerebral oxidative stress markers following aspartame ingestion

OBJECTIVE

The study evaluated changes in open field behaviours, cerebral cortical histomorphology and biochemical markers of oxidative stress following repeated administration of aspartame in mice.

METHODOLOGY

Adult mice were assigned into five groups of twelve each. Vehicle (distilled water), or aspartame (20, 40, 80 and 160mg/kg body weight) were administered orally for 28days. Horizontal locomotion, rearing and grooming were assessed after the first and last dose of aspartame. Sections of the cerebral cortex were processed and stained for general histology, and also examined for neuritic plaques using the Bielschwosky's protocol. Glial fibrillary acidic protein (GFAP) and neuron specific enolase (NSE) immunoreactivity were assessed using appropriate antibodies. Aspartate and antioxidant levels were also assayed from cerebral cortex homogenates. Data obtained were analysed using descriptive and inferential statistics.

RESULTS

Body weight and food consumption decreased significantly with aspartame consumption. Locomotion, rearing and grooming increased significantly after first dose, and with repeated administration of aspartame. Histological changes consistent with neuronal damage were seen at 40, 80 and 160mg/kg. Neuritic plaque formation was not evident; while GFAP-reactive astrocytes and NSE-reactive neurons increased at 40 and 80mg/kg but decreased at 160mg/kg. Superoxide dismutase and nitric oxide increased with increasing doses of aspartame, while aspartate levels showed no significant difference.

CONCLUSION

The study showed morphological alterations consistent with neuronal injury and biochemical changes of oxidative stress. These data therefore supports the need for caution in the indiscriminate use of aspartame as a non-nutritive sweetener.

Exogenous Testosterone, Aging, and Changes in Behavioral Response of Gonadally Intact Male Mice

This study tested the hypothesis that aging significantly affects the influence of exogenous testosterone on neurobehavior in gonadally intact male mice. Groups of prepubertal and aged male mice received daily vehicle or testosterone propionate (TP; 2.5 or 5.0 mg/kg intraperitoneal [i.p.]) for 21 days. Behaviors were assessed on days 1 and 21. Weight gain was significant in prepubertal mice. Locomotion and rearing increased in prepubertal mice after first dose and decreased after last dose of TP. Rearing was suppressed in aged mice throughout. Suppression of grooming occurred in both age groups at day 21. Significant increase in working memory in both age groups was seen in the radial-arm maze (at specific doses) and in prepubertal mice in the Y-maze. Elevated plus maze test showed mixed anxiolytic/anxiogenic effects. Aged mice had higher serum testosterone. In conclusion, age is an important determinant for the influence of exogenous testosterone on behavior in gonadally intact male mice.

Caffeine/sleep-deprivation interaction in mice produces complex memory effects

BACKGROUND

Sleep deprivation negatively impacts memory, causing deficits in memory processes. Of interest is any agent that can offset such deficits. Mice were given varying doses of caffeine for 14 days and then deprived of sleep for 6 hours by the 'gentle handling' method. Memory was assessed using the Novel Object Recognition Test and Y maze alternation.

PURPOSE

The study was designed to ascertain the impact of varying doses of caffeine combined with total sleep-deprivation on spatial and non spatial memory in mice.

METHODS

Adult Swiss Webster mice of both sexes were assigned to six groups viz., vehicle (distilled water), or one of five selected doses of caffeine (10, 20, 40, 80 and 120 mg/kg) for 14 days via the oral route. Open field novel object recognition test and Y maze spatial working memory tests were carried out on day 14. Results were analysed using multi-factorial ANOVA followed by Tukey HSD test and expressed as mean ± S.E.M, with p values less than 0.05 were considered statistically significant.

RESULTS

Novel object recognition tests (NOR) revealed that pre-training and pre-test sleep deprivation and caffeine combination impaired non spatial and spatial memory in male and female mice.

CONCLUSION

The study shows the complex interactions with memory that may arise when total sleep deprivation is superimposed on caffeine administration.