Modulatory Effects of Alkaloid Extract from Gongronema latifolium (Utazi) and Lasianthera africana (Editan) on Activities of Enzymes Relevant to Neurodegeneration

ABSTRACT

Most alkaloids are produced by plants as a defense mechanism against herbivores. Since alkaloids are known to possess pharmacological effects, this study sought to investigate the in vitro modulatory effect of alkaloid obtained from two commonly consumed vegetables in southern Nigeria, Lasianthera africana (editan) and Gongronema latifolium (utazi), on some enzyme activities relevant to neurodegeneration. Effects of the alkaloids on cholinesterases (acetylcholinesterase [AChE] and butyrylcholinesterase [BChE]) and monoamine oxidase (MAO) activities were determined in vitro. In addition, Fe²⁺ chelating ability as well as radical-scavenging abilities were determined. Alkaloid profile was also determined using gas chromatography coupled with flame ionization detector (GC-FID). The results revealed that the alkaloids inhibited AChE, BChE, and MAO activities in a concentration-dependent manner, such that the alkaloid from G. latifolium showed higher enzyme inhibition (AChE [IC₅₀ = 87.39 µg/ml], BChE [IC₅₀ = 118.65 µg/ml], and MAO [IC₅₀ = 61.37 µg/ml]) than L. africana (AChE = 115.60 µg/ml; BChE = 169.48 µg/ml; MAO = 73.72 µg/ml). In addition, GC-FID analysis revealed abundance of choline in both extracts. Gongronema latifolium and Lasianthera africana alkaloid extracts inhibit enzymes (acetylcholinesterase, butyrylcholinesterase, and monoamine oxidase) implicated in neurodegenerative diseases. Hence, these vegetables could offer dietary supplement in the management of neurodegenerative diseases.

KEYWORDS:

• acetylcholinesterase
• alkaloid
• neurodegeneration
• phytochemical
• vegetables

Declaration of interest

The authors declare no conflicts of interest. The authors alone are responsible for the content and writing of the article.

Ethical approval

All applicable international, national, and/or institutional guidelines for the care and use of animals were followed.

Additional information

Funding

None declared.

Notes on contributors

Esther E. Nwanna

Esther E. Nwanna, MTech, is a PhD student and lecturer in the Department of Biochemistry, Federal University of Technology Akure, Ondo State, Nigeria. Her research interests are in functional foods and nutraceuticals.

Adeniyi A. Adebayo

Adeniyi A. Adebayo, MTech, is a PhD student and member of Functional Food and Nutraceutical Research Unit, Department of Biochemistry, Federal University of Technology Akure, Ondo State, Nigeria.

Ganiyu Oboh

Ganiyu Oboh, PhD, is a professor and the head of the Functional Foods and Nutraceutical Unit in the Department of Biochemistry, Federal University of Technology Akure, Ondo State, Nigeria. His research interests are in functional foods and nutraceuticals.

Opeyemi B. Ogunsuyi

Opeyemi B. Ogunsuyi, MTech, is a lecturer in the Biomedical Technology Department and also a PhD student in the Biochemistry Department, Federal University of Technology Akure, Ondo State, Nigeria. His research interests are in functional foods and nutraceuticals.

Ayokunle O. Ademosun

Ayokunle O. Ademosun, PhD, is a lecturer in the Department of Biochemistry, Federal University of Technology Akure, Ondo State, Nigeria. His research interests are in functional foods and nutraceuticals.