Effect of an herbal formulation containing Peganum harmala L. and Fraxinus excelsior L. on oxidative stress, memory impairment and withdrawal syndrome induced by morphine

Protective effect of a hydromethanolic extract from Fraxinus excelsior L. bark against a rat model of aluminum chloride-induced Alzheimer's disease: Relevance to its anti-inflammatory and antioxidant effects

ETHNOPHARMACOLOGICAL RELEVANCE

Fraxinus excelsior L. (FE), commonly known as the ash, belongs to the Oleaceae family and has shown several pharmacological and biological properties, such as antioxidant, immunomodulatory, neuroprotective, and anti-inflammatory effects. It has also attracted the most attention toward neuroinflammation. Moreover, FE bark and leaves have been used to treat neurological disorders, aging, neuropathic pain, urinary complaints, and articular pain in traditional and ethnomedicine. Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder resulting from the involvement of amyloid-beta, metal-induced oxidative stress, and neuroinflammation.

AIM OF THE STUDY

The objective of the current study was to assess the neuroprotective effects of hydromethanolic extract from FE bark in an AlCl3-induced rat model of AD.

MATERIALS AND METHODS

The maceration process was utilized to prepare the hydromethanolic extract of FE bark, and characterized by LC-MS/MS. To assess the anti-AD effects of the FE extract, rats were categorized into five different groups, AlCl3; normal control; FE-treated groups at 50, 100, and 200 mg/kg. Passive avoidance learning test, Y-maze, open field, and elevated plus maze behavioral tests were evaluated on days 7 and 14 to analyze the cognitive impairments. Zymography analysis, biochemical tests, and histopathological changes were also followed in different groups.

RESULTS

LC-MS/MS analysis indicated the presence of coumarins, including isofraxidin7-O-diglucoside in the methanolic extract of FE as a new isofraxidin derivative in this genus. FE significantly improved memory and cognitive function, maintained weight, prevented neuronal damages, and preserved the hippocampus's histological features, as demonstrated by behavioral tests and histopathological analysis. FE increased anti-inflammatory MMP-2 activity, whereas it decreased that of inflammatory MMP-9. Moreover, FE increased plasma antioxidant capacity by enhancing CAT and GSH while decreasing nitrite levels in the serum of treated groups. In comparison between the treated groups, the rats that received high doses of the FE extract (200 mg/kg) showed the highest therapeutic effect.

CONCLUSION

FE rich in coumarins could be an effective anti-AD adjunct agent, passing through antioxidant and anti-inflammatory pathways. These results encourage further studies for the development of this extract as a promising agent in preventing, managing, or treating AD and related diseases.

Endogenous opiates and behavior: 2022

This paper is the forty-fifth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2022 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).