Narrative Review: The Effect of Vitamin A Deficiency on Gut Microbiota and Their Link with Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders defined by a lack of social behaviors, repetitive behaviors and nonverbal interactions, such as limited eye contact, facial expression, and body gesturing. It is not a single condition, but rather a multi-factorial disorder caused by hereditary and non-genetic risk factors, as well as their interaction. According to several studies, the gut microbiota may have a role in the pathophysiology of autism spectrum disorder. Various studies have found differences in the composition of the gastrointestinal (GI) microbiota in children with ASD compared to unaffected siblings and/or healthy unrelated controls. The processes that relate the gut microbiota to brain dysfunctions (the gut-brain axis) in ASD are yet to be fully understood. However, the differences in the gastrointestinal composition might be due to vitamin A deficiency because vitamin A (VA) plays a role in the regulation of the intestinal microbiota. This narrative review discusses the impact of vitamin A deficiency on the gut microbiota composition and tries to understand how this may contribute for the development and severity of ASD.

ALEXITHYMIA, SUICIDAL IDEATION AND BEHAVIOUR IN MOROCCAN PSYCHOACTIVE SUBSTANCE USERS

Alexithymia is an emotion regulation problem that may be related to suicidality, especially in patients with SUD. The study aimed at estimating the prevalence of alexithymia in Moroccan psychoactive substances users, and to establish the links between alexithymia and suicidal ideation and behaviors, anxiety and depression in drug-dependent patients. We also aimed to elucidate if alexithymia predicts suicidal thoughts and behaviors in these consumers. The study included 451 consecutively admitted patients with substance use. Consumers were examined with the Toronto alexi - thymia scale (TAS-20), State and Trait Anxiety Inventory (STAI- Y), Beck Depression Inventory (BDI) and The Columbia-Suicide Severity Rating Scale (C-SSRS). Among substance-dependent individuals, 72.7% was identified as a group with alexithymia. Current age and age at first substance use were lower in the alexithymic group (p<0.01). The mean STAI-Y state and C-SSRS scores were higher in the group with alexithymia (p<0.01). There was a statistically significant difference between the groups in terms of mean scores for anxiety traits (p<0.05) and no significant difference in terms of mean scores for depression. All of the scores correlated significantly with. Addicted patients with alexithymia could be targeted at prevent- ing the onset of suicidal thoughts and behaviour. The present study also evokes that whenever an emotional regulation disorder is observed, the possibility of anxio-depressive symptomatology and suicidality (ideation and behavior) needs to be assessed.

BRAIN TUMORS AMONG MOROCCAN ADOLESCENTS IN THE REGION OF RABAT-SALE-KENITRA, MOROCCO

Brain tumours refer to all tumors, both benign and malignant, which develop in the cerebral parenchyma. In Africa, including Morocco, there is a paucity of descriptive brain tumors data. The aim of this study to describe the epidemiological profile of brain tumors types among Moroccan adolescents. Our study is a descriptive epidemiological study targeting all ado- lescent patients, aged between 10 and 19, suffering from a brain tumor and admitted from January 1 to December 31, 2020, to the neuro- surgery department of the Hospital of Specialities-CHU-Rabat-Mo- rocco. During these period, the neurosurgery department admitted 179 patients diagnosed with a brain tumor, including 18 adolescents, which represents 10.05% of all admitted patients. The 18 teenagers found include 11 females patients and 7 males patients which means a sex-ratio Male/Female of 0,64. The average age of our patients is 13.05 years, with extremities ranging from 10 to 19 years. It was found that for the topographic distribution 50% of tumors are infratentorial and 50% are supratentorial. The most presented re- vealing symptomatology is headaches (12 patients, 66.67%). The other symptoms experienced by patients were fatigability (11 patients), diziness (10 patients), vomiting (8 patients), weightloss (8 patients), seizures (6 patients), visual disturbances (5 patients), balance disorder (4 patients), hemiparesis (3 patients), hypoacusis (2 patients) and other. We found that Astrocytomas come in first position of diagnosed tumors with a percentage of 22.22% followed by Vestibular schwannoma and Craniopharyngioma with a percentage of 16.67% each. The topographic diagnosis finds an infra-tentorial localization equal to the supratentorial localization with 50% each. A rare tumor was detected in our study, which is hemangiopericytoma in a 15-year-old male patient. The epidemiological profile of brain tumors in Morocco and more specifically in the Rabat-Salé-Kenitra region has similarities with other studies in Morocco and also presents differences. However, other multicenter studies are necessary in our country to establish a Moroccan national registry of brain tumors that can be used for other epidemiological studies on a continental scale.

Impact of lead sub-chronic toxicity on recognition memory and motor activity of Wistar rat

The aim of this research was to investigate the impact of lead nitrate administered in drinking water during 90 days (sub-chronic toxicity), on body weight gain, motor activity, brain lead accumulation and especially on recognition memory of Wistar rats. Two groups of young female Wistar rats were used. Treated rats received 20 mg L(-1) of lead nitrate diluted in drinking water, while control rats received drinking water only, for 3 months. An evolution of body weight, motor activity, object recognition memory and measure of brain lead levels has been evaluated. The body weight was taken weekly, whereas the memory abilities and the motor activity are measured once every fortnight alternatively, by submitting rats to the Open Field (OF) test and to the Novel Object Recognizing (NOR) memory test. The results have shown a non significant effect in gain of body weight. However, a high significance was shown for horizontal activity (p<0.01), long memory term (p<0.01), at the end of testing period and for brain lead levels (p<0.05) between studied groups.

Impact of aluminum sub-chronic toxicity on body weight and recognition memory of wistar rat

The aims of this study was to investigate the impact of aluminum nitrate administered in drinking water during 90 days (sub-chronic toxicity), on body weight gain, motor activity, brain aluminum accumulation and especially in recognition memory of wistar rats. Two groups of young female wistar rats were used. Treated rats received (80 mg L(-1)) of aluminum nitrate diluted in drinking water, while control rats received a drinking water only, for 3 months. An evolution of body weight, a motor activity, object recognition memory (NOR) and brain aluminum concentration has been evaluated. The body weight was taken weekly, whereas the memory abilities and the motor activity are measured once every fortnight alternatively, by submitting rats to the open field test and to the novel object recognizing memory test. The results have showed a significant decrease in rats' body weight (p < 0.05). Though, no significance was registered for motor activity. Nevertheless, a high significance is showed for recognition memory compared to control rats (p < 0.01), especially at the end of testing period, even the difference between control and aluminium treated rats in brain aluminum levels was not significant.