Dill tablet and Ocimum basilicum aqueous extract: Promising therapeutic agents for improving cognitive deficit in hypercholesterolemic rats

A Comprehensive Review of Essential Oils and Their Pharmacological Activities in Neurological Disorders: Exploring Neuroprotective Potential

Numerous studies have demonstrated essential oils' diverse chemical compositions and pharmacological properties encompassing antinociceptive, anxiolytic-like, and anticonvulsant activities, among other notable effects. The utilization of essential oils, whether inhaled, orally ingested, or applied topically, has commonly been employed as adjunctive therapy for individuals experiencing anxiety, insomnia, convulsions, pain, and cognitive impairment. The utilization of synthetic medications in the treatment of various disorders and symptoms is associated with a wide array of negative consequences. Consequently, numerous research groups across the globe have been prompted to explore the efficacy of natural alternatives such as essential oils. This review provides a comprehensive overview of the existing literature on the pharmacological properties of essential oils and their derived compounds and the underlying mechanisms responsible for these observed effects. The primary emphasis is on essential oils and their constituents, specifically targeting the nervous system and exhibiting significant potential in treating neurodegenerative disorders. The current state of research in this field is characterized by its preliminary nature, highlighting the necessity for a more comprehensive overlook of the therapeutic advantages of essential oils and their components. Integrating essential oils into conventional therapies can enhance the effectiveness of comprehensive treatment regimens for neurodegenerative diseases, offering a more holistic approach to addressing the multifaceted nature of these conditions.

Betaine Ameliorates Depressive-Like Behaviors in Zinc Oxide Nanoparticles Exposed Mice

The aim of the current study was to determine protective effects of betaine on depressive-like behaviors in zinc oxide nanoparticles (ZnO NPs) exposed mice. Forty male mice randomly allocated into four experimental groups. Group 1 kept as control and groups 2-4 received oral administration of betaine (30 mg/kg), ZnO NPs (600 mg/kg), and ZnO NPs (600 mg/kg) 1 h after pre-administration of betaine (30 mg/kg) for 7 days, respectively. Then, forced swimming test (FST), tail suspension test (TST), open field test (OFT), and rotarod tests were done. Furthermore, serum malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), and total antioxidant capacity (TAC) levels were determined. Hippocampal tissue samples were collected for histopathological assessment. According to the results, treatment with ZnO NPs significantly increased immobility time in the FST and TST (P<0.05). Betaine significantly decreased immobility time in the FST and TST (P<0.05). Pretreatment with betaine significantly decreased ZnO NPs-induced alterations in the FST and TST (P<0.05). The duration of staying on the rotarod and the numbers of crossings in the OFT significantly decreased in the mice that received ZnO NPs (P<0.05). These results were significantly improved in betaine+ZnO NPs treated mice as compared to the ZnO NPs group (P<0.05). Treatment with ZnO NPs significantly increased serum MDA level while decreased SOD and GPx compared to the control group (P<0.05). These changes were effectively ameliorated by pretreatment with betaine compared to the ZnO NPs group (P<0.05). No significant effect on serum TAC level was observed in all groups (P˃0.05). Administration of ZnO NPs decreased the thickness of hippocampus and pyramidal neurons in the hippocampal dentate gyrus (DG) and CA1 regions were sparsely arranged. Pretreatment with betaine caused an improvement in the histological features of the hippocampus when compared with ZnO NPs-treated mice. Taken together, these results suggest that betaine has protective role against ZnO NPs-induced toxicity in mice.

Connecting the Dots Between Hypercholesterolemia and Alzheimer’s Disease: A Potential Mechanism Based on 27-Hydroxycholesterol

Alzheimer’s disease (AD), the most common cause of dementia, is a complex and multifactorial disease involving genetic and environmental factors, with hypercholesterolemia considered as one of the risk factors. Numerous epidemiological studies have reported a positive association between AD and serum cholesterol levels, and experimental studies also provide evidence that elevated cholesterol levels accelerate AD pathology. However, the underlying mechanism of hypercholesterolemia accelerating AD pathogenesis is not clear. Here, we review the metabolism of cholesterol in the brain and focus on the role of oxysterols, aiming to reveal the link between hypercholesterolemia and AD. 27-hydroxycholesterol (27-OHC) is the major peripheral oxysterol that flows into the brain, and it affects β-amyloid (Aβ) production and elimination as well as influencing other pathogenic mechanisms of AD. Although the potential link between hypercholesterolemia and AD is well established, cholesterol-lowering drugs show mixed results in improving cognitive function. Nevertheless, drugs that target cholesterol exocytosis and conversion show benefits in improving AD pathology. Herbs and natural compounds with cholesterol-lowering properties also have a potential role in ameliorating cognition. Collectively, hypercholesterolemia is a causative risk factor for AD, and 27-OHC is likely a potential mechanism for hypercholesterolemia to promote AD pathology. Drugs that regulate cholesterol metabolism are probably beneficial for AD, but more research is needed to unravel the mechanisms involved in 27-OHC, which may lead to new therapeutic strategies for AD.

Mechanistic Aspects of Apiaceae Family Spices in Ameliorating Alzheimer's Disease

Alzheimer's disease (AD) is one of the most prevalent neurodegenerative diseases worldwide. In an effort to search for new strategies for treating AD, natural products have become candidates of choice. Plants are a rich source of bioactive and effective compounds used in treating numerous diseases. Various plant extracts are known to display neuroprotective activities by targeting different pathophysiological pathways in association with the diseases, such as inhibiting enzymes responsible for degrading neurotransmitters, reducing oxidative stress, neuroprotection, inhibiting amyloid plaque formation, and replenishing mitochondrial function. This review presented a comprehensive evaluation of the available scientific literature (in vivo, in vitro, and in silico) on the neuroprotective mechanisms displayed by the extracts/bioactive compounds from spices belonging to the Apiaceae family in ameliorating AD.