Ameliorative role of Syzygium aromaticum aqueous extract on synaptosomal tyrosine hydroxylase activity, oxidative stress parameters, and behavioral changes in lead-induced neurotoxicity in mice

Protective Effect of Protocatechuic Acid on Oxidative Damage and Cognitive Impairment in Pb-Induced Rats

Protocatechuic acid (PCA), a class of water-soluble phenolic acid abundant in the human diet, has been shown to be of great nutritional interest and to have medicinal value. However, the protective effects against lead (Pb)-induced body injury have not been elucidated. In this study, we explored the protective effect of PCA on Pb-induced oxidative damage and cognitive impairment in rats. The results showed that PCA could reduce the Pb content in rat bodies (blood, bone, brain, liver, and kidney) after Pb exposure. Moreover, PCA may inhibit Pb-induced oxidative damage by increasing the activity of antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and decreasing the level of malondialdehyde (MDA) in the brain, liver, and kidney. In addition, PCA may alleviate Pb-induced learning and memory impairment by upregulating neurotransmitter levels; maintaining the normal function of N-methyl-D-aspartate receptors (NMDARs); and promoting Ca2+ influx, thus activating signaling molecules, related protein kinases, and transcription factors in the cAMP-PKA-CREB pathway. In general, PCA could reduce oxidative stress and ameliorate the learning and memory deficits in Pb-treated rats, indicating that PCA may be an effective preventive agent and treatment or plumbism.

Neuroprotective effects of a combination of Boswellia papyrifera and Syzygium aromaticum on AlCl3 induced Alzheimer's disease in male albino rat

Alzheimer's disease (AD) is the most common neurodegenerative disease characterized by hippocampal, and cortical neuron deterioration, oxidative stress, and severe cognitive dysfunction. Aluminum is a neurotoxin inducer for cognitive impairments associated with AD. The treatment approaches for AD are unsatisfactory. Boswellia papyrifera and Syzygium aromaticum are known for their pharmacological assets, including antioxidant activity. Therefore, the current study explored the possible mitigating effects of a combination of Boswellia papyrifera and Syzygium aromaticum against aluminum chloride (AlCl3) induced AD. The AD model was established using AlCl3 (100 mg/kg), and the rats were orally administrated with Boswellia papyrifera or Syzygium aromaticum or a combination of them daily for 8 weeks. The Y-maze test was used to test cognition in the rats, while acetylcholinesterase (AChE) and oxidative stress markers were estimated in homogenates of the cerebral cortex and hippocampus. Also, the histopathological examination of the cortex and hippocampus were investigated. The results revealed that administration of either B. papyrifera or S. aromaticum extracts significantly improved the cognitive functions of AD rats, enhanced AChE levels, increased oxidative enzymes levels, including SOD and GSH, and reduced MDA levels in homogenates of the cerebral cortex and hippocampus and confirmed by improvement in histological examination. However, using a combination therapy gave better results compared to a single treatment. In conclusion, the present study provided primary evidence for using a combination of B. papyrifera and S. aromaticum to treat cognitive dysfunction associated with AlCl3 Induced AD by improving the AChE levels and modulating oxidative stress in the brain.

Gastroprotective mechanism of modified lvdou gancao decoction on ethanol-induced gastric lesions in mice: Involvement of Nrf-2/HO-1/NF-κB signaling pathway

Modified Lvdou Gancao decoction (MLG), a traditional Chinese medicine formula, has been put into clinical use to treat the diseases of the digestive system for a long run, showing great faculty in gastric protection and anti-inflammatory, whereas its protective mechanisms have not been determined. The current study puts the focus on the protective effect and its possible mechanisms of MLG on ethanol-induced gastric lesions in mice. In addition to various gastric lesion parameters and histopathology analysis, the activities of a list of relevant indicators in gastric mucosa were explored including ALDH, ADH, MDA, T-SOD, GSH-Px, and MPO, and the mechanisms were clarified using RT-qPCR, ELISA Western Blot and immunofluorescence staining. The results showed that MLG treatment induced significant increment of ADH, ALDH, T-SOD, GSH-Px, NO, PGE2 and SS activities in gastric tissues, while MPO, MDA, TNF-α and IL-1β levels were on the decline, both in a dose-dependent manner. In contrast to the model group, the mRNA expression of Nrf-2 and HO-1 in the MLG treated groups showed an upward trend while the NF-κB, TNFα, IL-1β and COX2 in the MLG treated groups had a downward trend simultaneously. Furthermore, the protein levels of p65, p-p65, IκBα, p-IκBα, iNOS, COX2 and p38 were inhibited, while Nrf2, HO-1, SOD1, SOD2 and eNOS were ramped up in MLG treatment groups. Immunofluorescence intensities of Nrf2 and HO-1 in the MLG treated groups were considerably enhanced, with p65 and IκBα diminished simultaneously, exhibiting similar trends to that of qPCR and western blot. To sum up, MLG could significantly ameliorate ethanol-induced gastric mucosal lesions in mice, which might be put down to the activation of alcohol metabolizing enzymes, attenuation of the oxidative damage and inflammatory response to maintain the gastric mucosa. The gastroprotective effect of MLG might be achieved through the diminution of damage factors and the enhancement of defensive factors involving NF-κB/Nrf2/HO-1 signaling pathway. We further confirmed that MLG has strong potential in preventing and treating ethanol-induced gastric lesions.