The Protective Effect of Omeprazole Against Traumatic Brain Injury: An Experimental Study

Long-term administration of omeprazole in mice: a study of behavior, inflammatory, and oxidative stress alterations with focus on central nervous system

Chronic use of omeprazole has been linked to central effects alongside with the global concern of increasing appearance of neuropsychiatric disorders. This study aimed to identifying behavioral, inflammatory, and oxidative stress alterations after long-term administration of omeprazole. C57BL/6 mice were divided in groups: OME and Sham, each received either solutions of omeprazole or vehicle, administered for 28 days by gavage. Results observed in the omeprazole-treated mice: Decrease in the crossing parameter in the open field, no change in the motor performance assessed by rotarod, an immobility time reduction in the forced swimming test, improved percentage of correct alternances in the Ymaze and an exploration time of the novel object reduction in the novel object recognition. Furthermore, a reduced weight gain and hippocampal weight were observed. There was an increase in the cytokine IL1-β levels in both prefrontal cortex (PFC) and serum, whereas TNF-α increased only in the PFC. Nitrite levels increased in the hippocampus (HP) and PFC, while malondialdehyde (MDA) and glutathione (GSH) levels decreased. These findings suggest that omeprazole improves depressive-like behavior and working memory, likely through the increase in nitrite and reduction in MDA levels in PFC and HP, whereas, the impairment of the recognition memory is more likely to be related to the reduced hippocampal weight. The diminished weight gain might be associated with the IL-1β increased levels in the peripheral blood. Altogether, omeprazole showed to have the potential to impact at central level and inflammatory and oxidative parameters might exert a role between it.

Antioxidant and neuroprotective effects of dexpanthenol in rats induced with traumatic brain injury

Trauma-induced primary damage is followed by secondary damage, exacerbating traumatic brain injury (TBI). Dexpanthenol has been shown to protect tissues against oxidative damage in various inflammation models. This study aimed to investigate possible antioxidant and neuroprotective effects of dexpanthenol in TBI. Wistar albino male rats were randomly assigned to control (n = 16), trauma (n = 16) and dexpanthenol (500 mg/kg; n = 14) groups. TBI was induced under anesthesia by dropping a 300 g weight from 70-cm height onto the skulls of the rats. Twenty-four hours after the trauma, the rats were decapitated and myeloperoxidase (MPO) levels, luminol- and lucigenin-enhanced chemiluminescence (CL), malondialdehyde (MDA) levels, superoxide dismutase (SOD) levels, and catalase (CAT) and caspase-3 activities were measured in brain tissues. Following transcardiac paraformaldehyde perfusion, histopathological damage was graded on hematoxylin-eosin-stained brain tissues. In the trauma group, MPO level, caspase-3 activity and luminol-lucigenin CL levels were elevated (p < 0.05-0.001) when compared to controls; meanwhile in the dexpanthenol group these increases were not seen (p < 0.05-0.001) and MDA levels were decreased (p < 0.05). Decreased SOD and CAT activities (p < 0.01) in the vehicle-treated TBI group were increased above control levels in the dexpanthenol group (p < 0.05-0.001). in the dexpanthenol group there was relatively less neuronal damage observed microscopically in the cortices after TBI. Dexpanthenol reduced oxidative damage, suppressed apoptosis by stimulating antioxidant systems and alleviated brain damage caused by TBI. Further experimental and clinical investigations are needed to confirm that dexpanthenol can be administered in the early stages of TBI.

Possible anti-inflammatory, antioxidant and neuroprotective effects of apigenin in the setting of mild traumatic brain injury: an investigation

OBJECTIVE

Apigenin is a plant flavone proven with biological properties such as anti-inflammatory, antioxidant, and antimicrobial effects. This study, it was aimed to examine the possible anti-inflammatory, antioxidant and neuroprotective effects of apigenin in the setting of mild traumatic brain injury (TBI) model.

METHODS

Wistar albino male rats were randomly assigned to groups: control (n = 9), TBI (n = 9), TBI + vehicle (n = 8), and TBI + Apigenin (20 and 40 mg/kg, immediately after trauma; n = 6 and n = 7). TBI was performed by dropping a 300 g weight from a height of 1 meter onto the skull under anesthesia. Neurological examination and tail suspension test applied before and 24 hours after trauma, as well as Y-maze and object recognition tests, after that rats were decapitated. In brain tissue, luminol- and lucigenin-enhanced chemiluminescence levels and cytokine ELISA levels were measured. Histological damage was scored. Data was analyzed with one-way ANOVA.

RESULTS

After TBI, luminol (p < 0.001) and lucigenin (p < 0.001) levels increased, and luminol and lucigenin levels decreased with apigenin treatments (p < 0.01-0.001). The tail suspension test score increased with trauma (p < 0.01). According to the pre-traumatic values, the number of entrances to the arms (p < 0.01) in the Y-maze decreased after trauma (p < 0.01). In the object recognition test, discrimination (p < 0.05) and recognition indexes (p < 0.05) decreased with trauma. There was no significant difference among trauma apigenin groups in behavioral tests. Interleukin (IL)-10 levels, one of the anti-inflammatory cytokines, decreased with trauma (p < 0.05), and increased with 20 and 40 mg apigenin treatment (p < 0.001 and p < 0.01, respectively). The histological damage score in cortex were decreased in apigenin 20 mg treatment group significantly (p < 0.05), the decrease observed in apigenin 40 mg group was not significant.

CONCLUSION

The results of this study revelead that apigenin 20 and 40 mg treatment may have neuroprotective effects in mild TBI via decreasing the the level of luminol and lucigenin and increasing the IL-10 levels. Additionally, apigenin 20 mg treatment ameliorated the trauma-induced cortical tissue damage.

Omeprazole Prevents Colistin-Induced Nephrotoxicity in Rats: Emphasis on Oxidative Stress, Inflammation, Apoptosis and Colistin Accumulation in Kidneys

The clinical value of colistin, a polymyxin antibiotic, is limited by its nephrotoxicity. Omeprazole is a commonly prescribed proton pump inhibitor. The current study aimed to evaluate the effects of the concomitant administration of omeprazole on colistin-induced nephrotoxicity in rats. Omeprazole significantly ameliorated colistin nephrotoxicity as evidenced by prevention in the rise in the serum level of creatinine, urea and cystactin C as well as urinary N-acetylglucosamine activity. This was confirmed by histological studies that indicated a decreased incidence of interstitial nephritis, degenerative cortical changes and collagen deposition. This was accompanied by the prevention of oxidative stress as omeprazole significantly inhibited the lipid peroxidation, glutathione depletion and enzymatic exhaustion of superoxide dismutase as well as catalase. Additionally, omeprazole inhibited the expression of interleukin-6 and tumor necrosis factor-α. Further, omeprazole inhibited the colistin-induced rise in Bax and the down-regulation of Bcl2 mRNA expression. An assessment of the serum levels of colistin revealed that omeprazole had no significant impact. However, it was observed that omeprazole significantly inhibited the accumulation of colistin in kidney tissues. In conclusion, omeprazole protects against colistin-induced nephrotoxicity. This can be attributed to, at least partly, omeprazole's anti-oxidant, anti-inflammatory and anti-apoptotic activities in addition to its ability to prevent the toxic accumulation of colistin in kidneys.

Omeprazole treatment manifests anxiolytic effects in a cysteamine hydrochloride induced mouse model of gastrointestinal disorder

Omeprazole, a proton pump inhibitor (PPI), has widely been used to treat various gastrointestinal (GI) disorders. Notably, many clinical symptoms of GI disorders have been known to be associated with anxiety. In recent years, an exponentially increased number of subjects with abnormal ageing, neurological deficits, and psychiatric problems simultaneously exhibit GI dysfunctions as well as anxiety. Considering the fact, drugs that are used to treat GI disorders can be speculated to mitigate anxiety-related symptoms, and vice versa. Although, omeprazole treatment has been reported to result in development of anxiety and neurocognitive decline, ample reports suggest that omeprazole treatment is beneficial for the positive regulation of neuroplasticity. While underlying mechanisms of omeprazole-mediated neurological alterations remain obscure, the available scientific data on the omeprazole induced adverse effects in the brain appear to be inadequate, uncertain, and controversial. Hence, this study revisited the effect of omeprazole treatment on the degree of anxiety-like behaviours in a cysteamine hydrochloride (HCl) induced mouse model of GI disorder using open field test (OFT), light-dark box (LDB) test and elevated plus maze (EPM). Results revealed that omeprazole treatment mitigates anxiety-related behaviours in the cysteamine HCl induced animal model of GI disorder. Thus, this study assuredly supports and validates the anxiolytic properties of omeprazole. However, the adverse effects associated with inappropriate intake of omeprazole may not completely be excluded. Therefore, this study advocates the future direction in determining the long-term effects of omeprazole on the brain functions.

Neuroprotective Effect of Cinnamaldehyde on Secondary Brain Injury After Traumatic Brain Injury in a Rat Model

OBJECTIVE

The aim of this study was to investigate the possible neuroprotective effects of cinnamaldehyde (CA) on secondary brain injury after traumatic brain injury (TBI) in a rat model.

METHODS

Rats were randomly divided into 4 groups: control (n = 9), TBI (n = 9), vehicle (0.1% Tween 80; n = 8), and CA (100 mg/kg) (n = 9). TBI was induced by the weight-drop model. In brain tissues, myeloperoxidase activity and the levels of luminol-enhanced and lucigenin-enhanced chemiluminescence were measured. Interleukin 1β, interleukin 6, tumor necrosis factor α, tumor growth factor β, caspase-3, and cleaved caspase-3 were evaluated with an enzyme-linked immunosorbent assay method. Brain injury was histopathologically graded after hematoxylin-eosin staining. Y-maze and novel object recognition tests were performed before TBI and within 24 hours of TBI.

RESULTS

Higher myeloperoxidase activity levels in the TBI group (P < 0.001) were suppressed in the CA group (P < 0.05). Luminol-enhanced and lucigenin-enhanced chemiluminescence, which were increased in the TBI group (P < 0.001, for both), were decreased in the group that received CA treatment (P < 0.001 for both). Compared with the increased histologic damage scores in the cerebral cortex and dentate gyrus of the TBI group (P < 0.001), scores of the CA group were lower (P < 0.001). Decreased number of entries and spontaneous alternation percentage in the Y-maze test of the TBI group (P < 0.05 and P < 0.01, respectively) were not evident in the CA group.

CONCLUSIONS

CA has shown neuroprotective effects by limiting neutrophil recruitment, suppressing reactive oxygen species and reducing histologic damage and acute hippocampal dysfunction.

Elevated anxiety, hypoactivity, memory deficits, decreases of brain serotonin and 5-HT-1A receptors expression in rats treated with omeprazole

Omeprazole (OM) is one of the most prescribed drugs worldwide for the treatment of hyperacidity and gastric reflux. However, concerns regarding its safety have emerged recently, and the drug is reported to enhance the risk for anxiety and cognitive deficits, particularly in elderly patients. The present study investigated these adverse effects, if any, in adult male rats. Associated changes in brain serotonin (5-hydroxytryptamine; 5-HT) and dopamine metabolism and the expression of 5-HT-1A receptors in the raphe and hippocampus were also determined. The drug was injected i.p. in doses of 10 and 20 mg/kg for 15 days. Both doses of OM decreased motor activity in an open field and impaired learning and memory in the Morris water maze test. Anxiety monitored in an elevated plus maze test was enhanced in rats treated with 20 mg/kg OM only. The levels of 5-HT and its metabolite 5-hydroxyindoleacetic acid and of homovanillic acid, a metabolite of dopamine, determined by HPLC-EC, were decreased in the brain of OM treated rats. The expression of 5-HT-1A receptor, determined by qRT-PCR, was reduced markedly in the hippocampus and moderately in the raphe. Our results provide evidence that OM use can reduce raphe hippocampal serotonin neurotransmission to lead to anxiety/depression and cognitive impairment. There is a need for increased awareness and prescription guidelines for therapeutic use of OM and possibly also other proton pump inhibitors.

The Effects of Proton Pump Inhibitors (Pantoprazole) on Pentylenetetrazole-Induced Epileptic Seizures in Rats and Neurotoxicity in the SH-SY5Y Human Neuroblastoma Cell Line

Recent studies have shown that proton pump inhibitors have positive effects on the nervous system. However, its effect on epileptic seizure and neuronal damage are still unclear. In this study, it was aimed to investigate the effect of pantoprazole on pentylenetetrazole-induced epileptic seizures in rats and neurotoxicity in the SH-SY5Y cell line. Animals were divided into three groups: control, saline (1 mL/kg serum physiologic), and pantoprazole (10 mg/kg). Pentylenetetrazole (45 mg/kg) was given to induce a seizure and a passive avoidance test trial was carried out to evaluate memory function. 8-hydroxy-2'-deoxyguanosine (8-OHdG), caspase-3, and brain-derived neurotrophic factor (BDNF) levels were measured in the brain by commercial kits. SH-SY5Y cells were treated with saline or pantoprazole for one hour, and then pentylenetetrazole (30 µm) was added to the medium to induce neurotoxicity. After 24 h, cell viability, total antioxidant, total oxidant status, and apoptosis were measured in SH-SY5Y cells. It was found that pantoprazole treatment postponed epileptic seizure onset, protected memory, reduced 8-OHdG, caspase-3, and also increased BDNF in the brain. In addition, it blocked pentylenetetrazole toxicity, apoptosis, increased antioxidant, and decreased oxidant status in SH-SY5Y cells. Pantoprazole significantly improved seizure, oxidative stress, and apoptosis. Thus, pantoprazole could be used as a supportive therapeutic agent in epilepsy.

Neuroprotective effects of mildronate in a rat model of traumatic brain injury

OBJECTIVE

Traumatic brain injury (TBI) is one of the most common preventable causes of mortality and morbidity. Inflammation, apoptosis, oxidative stress, and ischemia are some of the important pathophysiological mechanisms underlying neuronal loss after TBI. Mildronate is demonstrated to be beneficial in various experimental models of ischemic diseases via anti-inflammatory, antioxidant, and neuroprotective mechanisms. This study aimed to investigate possible antioxidant, anti-inflammatory, antiapoptotic, and neuroprotective effects of mildronate in a rat model of TBI.

METHODS

A total of 46 male rats were divided into three groups of control, saline-treated TBI, and mildronate-treated TBI. Both TBI groups were subjected to closed-head contusive weight-drop injuries followed by treatment with saline or mildronate (100 mg/kg) administered intraperitoneally. The forebrain was removed 24 h after trauma induction, the activities of myeloperoxidase (MPO) and caspase-3, levels of superoxide dismutase (SOD), luminol- and lucigenin-enhanced chemiluminescence were measured, and histomorphological evaluation of cerebral tissues was performed.

RESULTS

Increased MPO and caspase-3 activities in the vehicle-treated TBI group (p < 0.001) were suppressed in the mildronate-treated TBI group (p < 0.001). Similarly, increase in luminol and lucigenin levels (p < 0.001 and p < 0.01, respectively) in the vehicle-treated TBI group were decreased in the mildronate-treated TBI group (p < 0.001). Concomitantly, in the vehicle-treated TBI group, TBI-induced decrease in SOD activity (p < 0.01) was reversed with mildronate treatment (p < 0.05). On histopathological examination, TBI-induced damage in the cerebral cortex was lesser in the mildronate-treated TBI group than that in other groups.

CONCLUSION

This study revealed for the first time that mildronate, exhibits neuroprotective effects against TBI because of its anti-inflammatory, antiapoptotic, and antioxidant activities.

A Systematic Review of Closed Head Injury Models of Mild Traumatic Brain Injury in Mice and Rats

Mild TBI (mTBI) is a significant health concern. Animal models of mTBI are essential for understanding mechanisms, and pathological outcomes, as well as to test therapeutic interventions. A variety of closed head models of mTBI that incorporate different aspects (i.e., biomechanics) of the mTBI have been reported. The aim of the current review was to compile a comprehensive list of the closed head mTBI rodent models, along with the common data elements, and outcomes, with the goal to summarize the current state of the field. Publications were identified from a search of PubMed and Web of Science and screened for eligibility following PRISMA guidelines. Articles were included that were closed head injuries in which the authors classified the injury as mild in rats or mice. Injury model and animal-specific common data elements, as well as behavioral and histological outcomes, were collected and compiled from a total of 402 articles. Our results outline the wide variety of methods used to model mTBI. We also discovered that female rodents and both young and aged animals are under-represented in experimental mTBI studies. Our findings will aid in providing context comparing the injury models and provide a starting point for the selection of the most appropriate model of mTBI to address a specific hypothesis. We believe this review will be a useful starting place for determining what has been done and what knowledge is missing in the field to reduce the burden of mTBI.

Effect of oxidative stress in rostral ventrolateral medulla on sympathetic hyperactivity after traumatic brain injury

Sympathetic hyperactivity occurs in a subgroup of patients after traumatic brain injury (TBI). The rostral ventrolateral medulla (RVLM) is a key region for the activity of sympathetic nervous system. Oxidative stress in the RVLM is proved to be responsible for the increased level of sympathetic activity in animal models of hypertension and heart failure. In this study, we investigated whether oxidative stress in the RVLM contributed to the development of sympathetic hyperactivity after TBI in rats. Model of diffuse axonal injury was induced using Sprague-Dawley rats, and level of mean arterial pressure (MAP) and plasma Norepinephrine (NE) was measured to evaluate the sympathetic activity. For the assessment of oxidative stress, expression of reactive oxygen species (ROS), malondialdehyde (MDA), and superoxide dismutase (SOD) in the RVLM was determined. Microinjection of Tempol into the RVLM was performed to determine the effect of oxidative stress on sympathetic hyperactivity. According to the results, TBI led to elevated MAP and plasma NE in rats. It also induced a significantly increased level of ROS, MDA production and decreased level of SOD in the RVLM. The sympathetic activity, ROS, and MDA in the RVLM decreased significantly after microinjection of Tempol. Therefore, the present results suggested that oxidative stress in the RVLM was involved in the development of sympathetic hyperactivity following TBI.

Omeprazole protects against cisplatin-induced nephrotoxicity by alleviating oxidative stress, inflammation, and transporter-mediated cisplatin accumulation in rats and HK-2 cells

The present study assessed the therapeutic potential of omeprazole (OME), the most commonly prescribed proton pump inhibitor (PPI) used to treat gastroesophageal hyperacidity, against cisplatin (CP)-induced toxicity in human renal tubular HK-2 cells and rat kidneys. Herein, we observed that exposure of HK-2 cells to OME reversed the injury caused by CP, including enhancing cell viability and alleviating intracellular reactive oxygen species (ROS) generation and membrane damage. Concomitantly, acute exposure of male SD rats to CP induced histopathological changes, which were prevented by co-administration with OME. Inflammation and oxidative stress were inhibited by OME during CP-induced renal injury by increasing the activity of superoxide dismutase, and reducing the levels of malondialdehyde, both in vivo and in vitro. The expression levels of major inflammatory response markers were significantly decreased in HK-2 cells and rat kidneys in response to OME. OME reduced CP cellular uptake through organic cation transporters 2 (OCT2) and the prompt efflux of CP by P-glycoprotein (P-gp), thereby reducing the accumulation of CP in kidney tissue and increasing its serum levels. These data demonstrate that CP-induced kidney damage is positively correlated with its cellular accumulation. Concurrently, OME showed renoprotective effect against CP-induced toxicity in HK-2 cells and rat kidneys, by suppressing oxidative stress and mediating NF-κB-dependent inflammation, apoptosis, and transporter function. As OME is commonly used in combination with CP during chemotherapy treatment, this study highlights the clinical significance of OME in alleviating CP-induced nephrotoxicity.

Lack of mitochondrial ferritin aggravated neurological deficits via enhancing oxidative stress in a traumatic brain injury murine model

Oxidative stress has been strongly implicated in the pathogenesis of traumatic brain injury (TBI). Mitochondrial ferritin (Ftmt) is reported to be closely related to oxidative stress. However, whether Ftmt is involved in TBI-induced oxidative stress and neurological deficits remains unknown. In the present study, the controlled cortical impact model was established in wild-type and Ftmt knockout mice as a TBI model. The Ftmt expression, oxidative stress, neurological deficits, and brain injury were measured. We found that Ftmt expression was gradually decreased from 3 to 14 days post-TBI, while oxidative stress was gradually increased, as evidenced by reduced GSH and superoxide dismutase levels and elevated malondialdehyde and nitric oxide levels. Interestingly, the extent of reduced Ftmt expression in the brain was linearly correlated with oxidative stress. Knockout of Ftmt significantly exacerbated TBI-induced oxidative stress, intracerebral hemorrhage, brain infarction, edema, neurological severity score, memory impairment, and neurological deficits. However, all these effects in Ftmt knockout mice were markedly mitigated by pharmacological inhibition of oxidative stress using an antioxidant, N-acetylcysteine. Taken together, these results reveal an important correlation between Ftmt and oxidative stress after TBI. Ftmt deficiency aggravates TBI-induced brain injuries and neurological deficits, which at least partially through increasing oxidative stress levels. Our data suggest that Ftmt may be a promising molecular target for the treatment of TBI.