Propofol effects in rodent models of traumatic brain injury: a systematic review

The effect of Amantadine on recovery, postoperative cognitive dysfunction and pain after propofol anesthesia in mice

INTRODUCTION

Postoperative cognitive dysfunction (POCD) encompasses a spectrum of cognitive impairments following surgery, attributed to disruptions in brain homeostasis. The pathogenesis involves glutamate toxicity, GABA receptor dysfunction, and alterations in NMDA and AMPA receptors. This study aimed to investigate the impact of pre-anesthetic amantadine administration on postoperative recovery time, POCD, and stress-related pain levels when combined with propofol anesthesia.

METHODS

Twenty-four adult male BALB/C mice were divided into four groups: Control, Propofol, Amantadine, and Amantadine+Propofol. Amantadine and propofol doses were administered intraperitoneally based on previous literature. Recovery time, pain levels (assessed via tail pinch and hot plate tests), cognitive functions (evaluated through Morris Water Maze), and locomotor activity (measured via Open Field Test) were recorded.

RESULTS

Amantadine administration significantly reduced recovery time from propofol anesthesia, prolonged pain perception, and preserved cognitive functions compared to propofol alone. The time spent in the target quadrant in the Morris Water Maze was significantly longer in groups receiving amantadine. Additionally, the distance covered until finding the platform was significantly shorter in the propofol-only group.

DISCUSSION

Amantadine's neuroprotective effects, attributed to its antagonistic action on glutamate and NMDA receptors, mitigate the detrimental effects of propofol on cognitive function and pain perception. This study highlights the potential of combining amantadine with propofol to enhance postoperative outcomes.

CONCLUSION

Amantadine administration before propofol anesthesia positively influenced postoperative recovery, cognitive function preservation, and stress-related pain perception in mice. These findings suggest a potential therapeutic strategy to mitigate POCD and pain associated with surgery.

Evaluation of the Effects of Repetitive Anaesthesia Administration on the Brain Tissues and Cognitive Functions of Rats with Experimental Alzheimer's Disease

Introduction: We evaluated the effects of repeated ketamine, propofol, and ketamine + propofol administration on cognitive functions and brain tissue of elderly rat models with streptozotocin-induced Alzheimer's disease. Materials and Methods: Thirty elderly male Wistar Albino rats were divided into five groups: control (Group C), Alzheimer's (Group A), Alzheimer's + ketamine (Group AK), Alzheimer's + propofol (Group AP), and Alzheimer's + propofol + ketamine (Group APK). Alzheimer's disease was induced in Groups A, AK, AP, and APK via intracerebroventricular streptozotocin. Four weeks after surgery, ketamine, propofol, and ketamine + propofol were administered intraperitoneally for 3 days to Groups AK, AP, and APK, respectively. The radial arm maze test (RAMT) was performed in the initial, 1st, 2nd, 3rd, and 4th weeks after surgery and daily following anaesthesia. Blood and brain tissue samples were obtained. Results: The RAMT results of Groups A, AK, AP, and APK decreased compared to Group C 2 weeks after Alzheimer's disease onset. Compared to Group A, the RAMT results increased in Groups AK and APK after the first anaesthesia, and in Group AP after the second anaesthesia. Brain tissue paraoxonase-1 (PON-1) and catalase (CAT) activities were low, and the thiobarbituric acid reactive substance (TBARS) level was high in Group A compared to Group C. TBARS levels of Groups AP and APK were lower than Group A, while CAT activity was higher. PON-1 activity was higher in Groups AK, AP, and APK than in Group A. Histopathological changes decreased in Groups AP and AK. A decrease in p53 was found in Group C compared to Group A. Ketamine and propofol were found to be effective at Bcl-2 immunoexpression, but a decrease in Caspase-3 was observed in Group APK. GFAP immunoexpression increased in Group A compared to Group C and in Group AP compared to Group AK. Conclusions: Repetitive anaesthesia application was found to positively affect cognitive functions. This was supported by histopathological and biochemical markers.

Comparison between premortem histopathology findings in rats with and without traumatic brain injury: prospective application in forensic medicine

Background

The aim of this study was to compare pre-mortem histopathology findings in rats with and without traumatic brain injury (TBI) and its prospective application in forensic medicine.

Methods

This study involved 12 rats with 6 rats for each treatment group. This type of study is a laboratory experimental study with two independent groups design. The first group were rats that did not experience TBI. The second group was a group of rats with TBI. The subjects of this study were Rattus norvegicus rats, adult males, 4-8 weeks old, weighing 150-200 grams. On the 8 th day after the rats experienced traumatic brain injury, the rats were then euthanized using the cervical dislocation method, after euthanasia the rats were given craniotomy and brain tissue was taken for histopathology examination.

Results

The description of histopathology changes in the brain organs in the group of rat without TBI found that neuron cells looked normal although there were also degeneration (21.16 ± 2.56/FV), necrosis (5.75 ± 0.98/FV), apoptosis (2.91 ± 0.80/FV), congestion ( 0.91 ± 0.49/FV), inflammatory cells (4.58 ± 1.15/FV) and hemorrhage (2.41 ± 1.11/FV). Changes in the rat traumatic brain injury group showed a lot of damage to neuron cells in the form of degeneration (48.41 ± 3.27/FV), necrosis (36.66 ± 2.89/FV), apoptosis (18.91 ± 1.24/FV), congestion (2.50 ±0.31/FV), inflammatory cells (11.41 ± 1.71/FV) and hemorrhage (10.08 ± 2.17/FV). Based on the results of statistical analysis, it can be seen that in all parameters there is a significant difference (p ≤ 0.001).

Conclusions

The premortem histopathology findings in rats with and without TBI which can be used for the benefit of forensic medicine in determining whether TBI is present or not. It is necessary to look more closely at the histopathology changes in the form of necrosis, apoptosis and hemorrhage.

Oxygen saturation profile in traumatic brain injury animal model after propofol administration

Traumatic brain injury (TBI) is a traumatic that often leads to death due to untreatable cerebral hypoxia, indicated by oxygen saturation of <90%. Cerebral hypoxia is rarely monitored and thereby often overlooked as a cause of mortality and monitoring oxygen saturation is an accurate method to detect the condition. Propofol, an anesthetic agent, is commonly used in the management of TBI; however, its effect on brain tissue and cerebral hypoxia in TBI cases is not well understood. The aim of this study was to evaluate the profile of oxygen saturation in TBI animal model after propofol administration. A laboratory experimental study was conducted, involving 18 male Rattus novergicus rats (aged 4-8 weeks with weight between 150-200 grams) divided into three different treatment groups (non-TBI, TBI without propofol, and TBI with propofol). Oxygen saturation was measured regularly from day 1 to day 8 using pulse oximetry. The oxygen saturation percentages were compared between the TBI rats with and without propofol administration using independent Student t-rest. The results revealed significant reductions of oxygen saturation levels of animals within propofol-treated TBI group compared to that of the untreated-TBI group (p<0.05), with the average oxygen saturation ranging from 80.8%±6.96% vs 86.8%±5.48%. This finding suggests a reducing effect of propofol administration on oxygen saturation levels in rats with TBI and this potentially causes cerebral hypoxia.

Are GABAergic drugs beneficial in providing neuroprotection after traumatic brain injuries? A comprehensive literature review of preclinical studies

Traumatic brain injuries (TBI) caused by physical impact to the brain can adversely impact the welfare and well-being of the affected individuals. One of the leading causes of mortality and dysfunction in the world, TBI is a major public health problem facing the human community. Drugs that target GABAergic neurotransmission are commonly used for sedation in clinical TBI yet their potential to cause neuroprotection is unclear. In this paper, I have performed a rigorous literature review of the neuroprotective effects of drugs that increase GABAergic currents based on the results reported in preclinical literature. The drugs covered in this review include the following: propofol, benzodiazepines, barbiturates, isoflurane, and other drugs that are agonists of GABAA receptors. A careful review of numerous preclinical studies reveals that these drugs fail to produce any neuroprotection after a primary impact to the brain. In numerous circumstances, they could be detrimental to neuroprotection by increasing the size of the contusional brain tissue and by severely interfering with behavioral and functional recovery. Therefore, anesthetic agents that work by enhancing the effect of neurotransmitter GABA should be administered with caution of TBI patients until a clear and concrete picture of their neuroprotective efficacy emerges in the clinical literature.