The Protective Role of Carnosic Acid against Beta‐Amyloid Toxicity in Rats

Abstract

Oxidative stress is one of the pathological mechanisms responsible for the beta- amyloid cascade associated with Alzheimer's disease (AD). Previous studies have demonstrated the role of carnosic acid (CA), an effective antioxidant, in combating oxidative stress. A progressive cognitive decline is one of the hallmarks of AD. Thus, we attempted to determine whether the administration of CA protects against memory deficit caused by beta-amyloid toxicity in rats. Beta-amyloid (1–40) was injected by stereotaxic surgery into the Ca1 region of the hippocampus of rats in the Amyloid beta (Aβ) groups. CA was delivered intraperitoneally, before and after surgery in animals in the CA groups. Passive avoidance learning and spontaneous alternation behavior were evaluated using the shuttle box and the Y-maze, respectively. The degenerating hippocampal neurons were detected by fluoro-jade b staining. We observed that beta-amyloid (1–40) can induce neurodegeneration in the Ca1 region of the hippocampus by using fluoro-jade b staining. Also, the behavioral tests revealed that CA may recover the passive avoidance learning and spontaneous alternation behavior scores in the Aβ + CA group, in comparison with the Aβ group. We found that CA may ameliorate the spatial and learning memory deficits induced by the toxicity of beta-amyloid in the rat hippocampus.

The role of rosemary extract (40% carnosic acid) in degeneration of hippocampal neurons induced by kainic acid in the rat:The behavioral and histochemical approach

“…Consistent with these findings, a previous study [52] in an experimental model of Alzheimer's disease in rats indicated that pretreatment with CA as an effective component of RE, can reduce neuronal death in hippocampus CA1. We also found that CA might ameliorate memory deficit beta-amyloid-induced toxicity in the rat hippocampus [53]. Considering that oxidative stress is one of the pathological mechanisms responsible for the beta-amyloid cascade associated with Alzheimer's disease, it appears that CA (as well as RE) plays multiple roles in the free radical chain reaction as an antioxidant.…”

Carnosic acid protects normal mouse hepatocytes against H2O2‐induced cytotoxicity via sirtuin 1‐mediated signaling

“…Carnosic acid has been reported to protect the cells from various types of oxidative stress . Activation of the antioxidant defense system, Nrf2 activation, and subsequent production of phase II enzymes is a commonly accepted mechanism for the activity of CA.…”

Nutritional and Pharmacological Strategies to Regulate Microglial Polarization in Cognitive Aging and Alzheimer’s Disease

“…Moreover, carnosic acid was able to improve cognitive deficits in an Aβ40-induced AD rat model (Rasoolijazi et al, 2013). In another study, oral administration of ferulic acid, found in seeds and cereals, particularly flaxseed (Beejmohun et al, 2007), inhibited microglial activation in an Aβ42-induced AD mouse model by decreasing IFN-gamma levels in the hippocampus (Kim et al, 2004).…”