The effect of Brucella abortus on glial activation and cell death in adult male rat's hippocampus.

A zoonotic disease called brucellosis can cause flu-like symptoms and heart inflammation. The bacteria responsible for this disease can also enter the brain, causing a condition called neurobrucellosis that can result in long-term neurological problems. In this study, researchers aimed to determine the changes in the hippocampal cells of rats infected with Brucella. For the study, 24 adult male albino rats were inoculated with 1 × 106 CFU Brucella abortus 544. The rats were then deeply anesthetized, and their hippocampus samples were taken for stereological, histological, and molecular studies. The results showed that the infected rats had increased microgliosis and astrogliosis. Furthermore, a high level of caspase-3 in their hippocampal tissue indicated their susceptibility to apoptosis. Additionally, there was a decrease in expression of Ki67, which further supported this. Sholl's analysis confirmed a significant failure in glial morphology. The study demonstrated that the pathogen has the ability to destroy the hippocampus and potentially affect its normal physiology. However, more research is needed to clarify various aspects of neurobrucellosis.

The elderberry diet protection against intrahippocampal Aß-induced memory dysfunction; the abrogated apoptosis and neuroinflammation.

This study evaluates whether elderberry (EB) effectively decreases the inflammation and oxidative stress in the brain cells to reduce Aß toxicity. In the Aß + EB group, EB powder was added to rats' routine diet for eight consecutive weeks. Then, spatial memory, working memory, and long-term memory, were measured using the Morris water maze, T-maze, and passive avoidance test. Also, in this investigation immunohistopathology, distribution of hippocampal cells, and gene expression was carried out. Voronoi tessellation method was used to estimate the spatial distribution of the cells in the hippocampus. In addition to improving the memory functions of rats with Aß toxicity, a reduction in astrogliosis and astrocytes process length and the number of branches and intersections distal to the soma was observed in their hippocampus compared to the control group. Further analysis indicated that the EB diet decreased the caspase-3 expression in the hippocampus of rats with Aß toxicity. Also, EB protected hippocampal pyramidal neurons against Aß toxicity and improved the spatial distribution of the hippocampal neurons. Moreover, EB decreased the expression of inflammatory and apoptotic genes. Overall, our study suggest that EB can be considered a potent modifier of astrocytes' reactivation and inflammatory responses.

Tramadol-induced apoptosis in auditory hair cells of adult male rats.

Reports have emerged on the sudden opioid-induced auditory hearing loss, and the underlying pathology is not fully understood. The present study aimed to determine the mechanism of action of these drugs in the inner ear. For this purpose, 20 rats were treated with 50 mg/kg tramadol daily for three weeks. Next, the stereological and immunohistochemical alteration of the inner hair cells under chronic exposure to tramadol was evaluated. The results revealed that tramadol induced hair cell degeneration and decreased bipolar neurons of the spiral ganglion and the thickness of stria vascularis. Moreover, immunohistochemistry showed that tramadol caused apoptosis in inner hair cells and bipolar neurons. These findings indicate that tramadol induces apoptosis in auditory hair cells, suggesting that tramadol may cause hearing loss and ototoxicity.

COVID-19 causes neuronal degeneration and reduces neurogenesis in human hippocampus.

Recent investigations of COVID-19 have largely focused on the effects of this novel virus on the vital organs in order to efficiently assist individuals who have recovered from the disease. In the present study we used hippocampal tissue samples extracted from people who died after COVID-19. Utilizing histological techniques to analyze glial and neuronal cells we illuminated a massive degeneration of neuronal cells and changes in glial cells morphology in hippocampal samples. The results showed that in hippocampus of the studied brains there were morphological changes in pyramidal cells, an increase in apoptosis, a drop in neurogenesis, and change in spatial distribution of neurons in the pyramidal and granular layer. It was also demonstrated that COVID-19 alter the morphological characteristics and distribution of astrocyte and microglia cells. While the exact mechanism(s) by which the virus causes neuronal loss and morphology in the central nervous system (CNS) remains to be determined, it is necessary to monitor the effect of SARS-CoV-2 infection on CNS compartments like the hippocampus in future investigations. As a result of what happened in the hippocampus secondary to COVID-19, memory impairment may be a long-term neurological complication which can be a predisposing factor for neurodegenerative disorders through neuroinflammation and oxidative stress mechanisms.

Different Strains of BK Polyomavirus: VP1 Sequences in a Group of Iranian Prostate Cancer Patients.

PURPOSE: BK virus (BKV) has a worldwide seroprevalence in humans. Based on sequences of the major capsid proteins, i.e. viral protein 1 (VP1), there are four BKV genotypes. Each genotype has its own subtypes, and wasshown to be circulating independently in the human population. The aim of this study was to determine BKVgenotypes and subtypes among Iranian patients with prostatic cancer, benign prostatic hyperplasia, and kidney transplantation. MATERIALS AND METHODS: BKV DNA was extracted from prostatic cancers and benign prostatic hyperplasia blocks and also urine of kidney transplantation patients. BKV (VP1) gene was amplified partially (327nt) by homemade polymerase chain reactions and subjected for sequencing and phylogenetic analysis. Bioedit version 7.0 and Mega version 5.0 were used for sequence analysis and for comparing the results with world-driven BKV sequences. RESULTS: All of BKV VP1 genes which were derived from Iranian patients were classified with subtype 1b2 strains from Germany and Turkey. Predicted amino acid sequences from the studied region of VP1 showed that all of these nucleotide diversities could change amino acid sequence numbers 60, 68, 72, 73 and 82 among VP1. CONCLUSION: The interesting point was that genetic analysis of derived sequences showed a different feature of genetic diversity among Iranian sequences. This feature has not been reported yet. This characteristic feature of Iranian BKV VP1 gene provides a unique cluster of sequences in phylogenetic tree.