Carob Seed Peels Effect on Cognitive Impairment and Oxidative Stress Status in Methionine-Induced Mice Models of Schizophrenia

Abstract

Ceratonia siliqua L. (Carob tree) is a Mediterranean evergreen, well known for its medicinal properties. The different parts of Carob were proven to exert antidiabetic, antibacterial, antifungal, and antiproliferative effects. Hence, the present paper aims to validate the positive correlation between the high antioxidant activity of carob seed peels and the improvement of negative symptoms of schizophrenia. Materials & Methods: The antioxidant activity was carried out using the β-carotene test. Methionine and carob seed peels (CSP) extracts (50 and 100 mg/kg) were orally administrated to mice for a week. After administration, behavioral tests were assessed using the Y-maze, elevated plus maze, and forced swimming tests, as well as the novel object recognition task. Furthermore, the oxidative stress status was evaluated by analyzing the levels of the antioxidant enzymes: Superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde levels (MDA). Results: Both extracts exhibited remarkable antioxidant activity and showed antibacterial effect against Gram-positive bacteria tested (Bacillus subtilis and Staphylococcus aureus) and against Pseudomonas aeruginosa (Gram-negative). Therefore, Escherichia coli was very resistant. The behavioral tests proved the efficacy of CSP in enhancing the cognitive impairment of animal models of schizophrenia. Hence, the stated correlation between oxidative stress and schizophrenia was confirmed by the increased SOD and GPx activities and the decreased MDA level. Conclusions: The present study gave further confirmation of the potential correlation between oxidative stress and the development of psychiatric disorders and highlighted the use of natural antioxidants, especially Ceratonia siliqua L. in the improvement of cognitive impairment in the dementia of schizophrenia.

Ceratonia siliqua L. Pod Extract: From Phytochemical Characterization to Liposomal Formulation and Evaluation of Behaviour in Cells

“…C. siliqua pods are known for their antioxidant properties that are of value for the amelioration and prevention of many disorders [ 33 , 34 ]. In the literature, there are many studies comparing different extraction methods to prepare an active extract.…”

Biological Activities of Ceratonia siliqua Pod and Seed Extracts: A Comparative Analysis of Two Cretan Cultivars

“…In general, under hypoxic conditions, the percentage of GSH stimulation was higher compared to normoxic ones, most probably due to the fact that hypoxia minimized basal GSH levels, as previously shown in various cell types [69,70]. Although there are several reports on the beneficial effects of various carob extracts on the GSH levels in whole organisms, mainly as part of their antioxidant defenses and during detoxification processes [71][72][73][74], this is the first study showing that C. siliqua extracts stimulate GSH at the cellular level.…”

Carob (Ceratonia siliqua L.) Seed Constituents: A Comprehensive Review of Composition, Chemical Profile, and Diverse Applications

“…Te potential health benefts of carob seed peels were studies by Lakkab et al [26,29] and Rico et al [27], who confrmed their remarkable antioxidant properties. Te studies conducted by these researchers brought to light the richness of bioactive compounds.…”

“…According to the research carried out by Lakkab et al [29], it was discovered that CSP demonstrated a markedly greater accumulation of total phenolic content, amounting to 9573 ± 1 mg GAE/100 g extract in contrast to other by-products, such as potato peel which only registered 68.7 ± 5.7 mg GAE/100 g dry weight [30] and carob pulp (4.53 ± 0.8 mg/100 g of dry matter) [10], which are typically recommended for similar benefciation procedures. CSP also demonstrated the greatest ability to inhibit the discoloration of β-carotene compared to BHT (58.3% versus 46%) [29]. Tis was explained by high content of phenolic compounds.…”