Procyanidin B2 3″-O-gallate Isolated from Reynoutria elliptica Prevents Glutamate-Induced HT22 Cell Death by Blocking the Accumulation of Intracellular Reactive Oxygen Species

Neuroprotective Potential of Seed Extracts: Review of In Vitro and In Vivo Studies

INTRODUCTION

Neurodegenerative diseases are characterized by neuronal dysfunction and death. Studies suggest that some seed extracts have a neuroprotective effect. Considering the increased incidence of these diseases and the need for new effective therapies with fewer side effects, this review aimed to assess the evidence of the efficacy and safety of seed extracts in experimental models of neurodegeneration.

MATERIAL AND METHOD

The search was carried out through studies published between 2000 and 2021 in Science Direct, PubMed, Scientific Electronic Library Online (SciELO), and Latin American Literature in Health Sciences (LILACS) databases, in which the effects of seed extracts in in vitro and in vivo experimental models of neurodegeneration were investigated. Based on the eligibility criteria, 47 studies were selected for this review.

RESULTS

In the in vitro models, the neuroprotection of the seed extracts was a result of their antioxidant, anti-inflammatory, and anti-apoptotic properties. In the in vivo models, neuroprotection resulted from the antioxidant and anti-inflammatory properties, a decrease in motor deficits, an improvement in learning and memory, as well as the increased release of neurotransmitters. The results show promise for the future of clinical research on new therapies for neurodegenerative diseases. However, the studies are still limited, which does not allow us to extrapolate the results to human beings with ND.

CONCLUSIONS

Therefore, clinical trials are needed in order to prove the results of the in vitro and in vivo studies, as well as to assess the ideal, safe, and effective dose of these seed extracts in patients with neurodegenerative diseases.

Natural products targeting mitochondria: emerging therapeutics for age-associated neurological disorders

Mitochondria are the primary source of energy production in the brain thereby supporting most of its activity. However, mitochondria become inefficient and dysfunctional with age and to a greater extent in neurological disorders. Thus, mitochondria represent an emerging drug target for many age-associated neurological disorders. This review summarizes recent advances (covering from 2010 to May 2020) in the use of natural products from plant, animal, and microbial sources as potential neuroprotective agents to restore mitochondrial function. Natural products from diverse classes of chemical structures are discussed and organized according to their mechanism of action on mitochondria in terms of modulation of biogenesis, dynamics, bioenergetics, calcium homeostasis, and membrane potential, as well as inhibition of the oxytosis/ferroptosis pathway. This analysis emphasizes the significant value of natural products for mitochondrial pharmacology as well as the opportunities and challenges for the discovery and development of future neurotherapeutics.

Defatted Seeds of Oenothera biennis as a Potential Functional Food Ingredient for Diabetes

The defatted seeds of Oenothera biennis (DSOB) are a by-product of evening primrose oil production that are currently not effectively used. In this study, α-glucosidase inhibition, aldose reductase inhibition, antioxidant capacity, polyphenol composition, and nutritional value (carbohydrates, proteins, minerals, fat, organic acid, and tocopherols) of DSOB were evaluated using the seeds of Oenothera biennis (SOB) as a reference. DSOB was an excellent inhibitor of α-glucosidase (IC₅₀ = 3.31 μg/mL) and aldose reductase (IC₅₀ = 2.56 μg/mL). DSOB also showed considerable antioxidant capacities (scavenging of 2,2-diphenyl-1-picrylhydrazyl, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid, nitric oxide, peroxynitrite, and hydroxyl radicals). DSOB was a reservoir of polyphenols, and 25 compounds in DSOB were temporarily identified by liquid chromatography coupled with electrospray ionization–quadrupole time of flight–mass spectrometry analysis. Moreover, the carbohydrate, protein, and mineral content of DSOB were increased compared to that of SOB. DSOB contained large amounts of fiber and low levels of sugars, and was rich in calcium and iron. These results imply that DSOB may be a potential functional food ingredient for diabetes, providing excellent economic and environmental benefits.