Aloe vera Leaf Extract Reduced BBB Permeability and Improved Neurological Results after Traumatic Brain Injury: The Role of Oxidative Stress.

Introduction: Recognizing the importance of medicinal plants and the absence of specific medications for traumatic brain injury (TBI) treatment, this study was conducted to evaluate the effects of an aqueous extract of Aloe vera on oxidative stress, blood-brain barrier (BBB) permeability, and neurological scores following TBI. Materials and Methods: Adult male rats were categorized into five groups: sham, TBI, vehicle, low-dose Aloe vera (LA), and high-dose Aloe vera (HA). We induced diffuse TBI using the Marmaro model and administered the aqueous Aloe vera leaf extract, as well as vehicle, via intraperitoneal injection half an hour after TBI. Neurological outcomes were assessed both before and several hours after TBI. Additionally, oxidative stress factors were measured 24 hr after TBI, and Evans blue content (a BBB permeability index) was determined 5 hr after TBI in both serum and brain. Results: Both LA and HA reduced the increase in BBB permeability after TBI, with HA having a more pronounced effect than LA. Both Aloe vera doses decreased brain MDA levels, increased brain TAC, and lowered both serum and brain PC levels. The impact of Aloe vera on brain oxidative parameters was more significant than on serum. HA also counteracted the declining effects of TBI on neurological outcomes at 4 and 24 hr post-TBI. Conclusion: This study suggests that Aloe vera extract may reduce BBB permeability and improve neurological outcomes after TBI by decreasing oxidative factors and increasing antioxidant factors.

Anti-edema effect of Aloe vera leaf extract following traumatic brain injury: Role of pro-inflammatory cytokines.

OBJECTIVE: Based on anti-inflammatory effects of Aloe vera, the effect of aqueous extract of this plant on brain edema and changes in some pro-inflammatory cytokines was investigated after traumatic brain injury (TBI). MATERIALS AND METHODS: In this study, adult male Wistar rats were divided into 5 groups: Sham, TBI, vehicle (Veh), and low dose (LA) and high dose (HA) Aloe vera. The vehicle and aqueous extract of Aloe vera were injected intraperitoneally 30 min after induction of diffuse TBI by Marmarou's method. Brain edema (brain water content), and transforming growth factor beta (TGF-ß), tumor necrosis factor alpha (TNFα), interleukin 6 (IL-6) and IL-1ß levels in serum and brain were measured 24 hr after TBI induction. RESULTS: Increased brain edema by TBI was reduced by both LA and HA (p<0.01 and p<0.05, respectively). IL-6 increased in the brain of TBI group compared to sham, and which was inhibited by both Aloe vera doses compared to Veh (p<0.001). The differences in the IL-6 serum levels among Veh, LA and HA groups were not significant. Increases in serum and brain IL-1ß levels were reduced only in the HA group (p<0.001). Although only in the brain, TNF-α level increased after trauma, but both LA and HA inhibited it in a dose-dependent manner (p<0.01 and p<0.05, respectively) . The amount of TGF-ß in the brain was reduced by both doses of the extract (p<0.001). CONCLUSION: These results indicated that Aloe vera has a neuroprotective effect induced by reducing brain edema. The probable mechanism particularly for HA is decreasing levels of pro-inflammatory cytokines such as TGF-ß, TNF-α, IL-6 and IL-1ß.