The Therapeutic Value of Solanum Steroidal (Glyco)Alkaloids: A 10-Year Comprehensive Review

Abstract

Steroidal (glycol)alkaloids S(G)As are secondary metabolites made of a nitrogen-containing steroidal skeleton linked to a (poly)saccharide, naturally occurring in the members of the Solanaceae and Liliaceae plant families. The genus Solanum is familiar to all of us as a food source (tomato, potato, eggplant), but a few populations have also made it part of their ethnobotany for their medicinal properties. The recent development of the isolation, purification and analysis techniques have shed light on the structural diversity among the SGAs family, thus attracting scientists to investigate their various pharmacological properties. This review aims to overview the recent literature (2012-2022) on the pharmacological benefits displayed by the SGAs family. Over 17 different potential therapeutic applications (antibiotic, antiviral, anti-inflammatory, etc.) were reported over the past ten years, and this unique review analyzes each pharmacological effect independently without discrimination of either the SGA's chemical identity or their sources. A strong emphasis is placed on the discovery of their biological targets and the subsequent cellular mechanisms, discussing in vitro to in vivo biological data. The therapeutic value and the challenges of the solanum steroidal glycoalkaloid family is debated to provide new insights for future research towards clinical development.

Keywords: Solanum; alkaloid; bioactivity; glycoalkaloid; secondary metabolites; steroid.

Figure 1

Diagram of the selection process for the scoping review.

Figure 2

Steroid categories according to their carbon framework.

Figure 3

Classification of steroidal alkaloids.

Figure 4

Chemical structures of the main oligosaccharide units of Solanum SGAs.

Figure 5

Chemical structure of some popular Solanum SGAs isolated from potato, tomato, and eggplant.

Figure 6

Summary of the pharmacological effects induced by Solanum SGAs. (Up arrow) = overexpressed, synthesis or activation. (Down arrow) = underexpressed, degradation or inactivation.