Among health enthusiasts, soursop has made a name for itself for the numerous health benefits it offers. Also called graviola or guanábana, the plant is packed with flavonoids, alkaloids, and other compounds credited for its effects on alleviating various conditions, including diabetes, parasitic infections, and cystitis.1
However, it is soursop's effects on immunity that spark the most interest of the medical world. To shed more light on the topic, this in vitro trial examined the potential immune-boosting effects of soursop leaf extracts.
In this trial, South Korean researchers used steam or 50% ethanol soursop leaf extracts, mainly rich in two flavonols: kaempferol-3-O-rutinoside and quercetin-3-O-rutinoside.
Researchers wanted to see whether soursop can modulate the immune response triggered by inflammatory mediators. To determine that, they worked on macrophage-like cells (RAW 264.7). Macrophages are cells essential for immunity and immune responses.
Cells were first treated with various concentrations of the steam and ethanol soursop leaf extracts. They were also treated with an endotoxin (lipopolysaccharide) to trigger inflammation, while the researchers observed the changes that ensued.
Treating the cells with soursop extract led to macrophage activation and changed their morphology to an extended form, which are the first steps in the activation of the innate immune response.
For reference, the innate immune system is the first line of defense against invading pathogens.
What Does this Mean?
The results of this in vitro trial suggest that soursop leaves can enhance immunity by activation of the mitogen-activated protein kinase signaling pathways.
While soursop fruits have already been linked to many health benefits, not much research has been done on the leaves. As shown in this study, they could potentially be used to make functional foods for improving the immune response, particularly in immunocompromised patients. However, more studies are needed to explore these benefits.
- Evidence-based Complementary and Alternative Medicine, Immunomodulatory Efficacy of Standardized Annona muricata (Graviola) Leaf Extract via Activation of Mitogen-Activated Protein Kinase Pathways in RAW 264.7 Macrophages, 2016
- Molecules. (2022). Pharmacological Activities of Soursop (Annona muricata Lin.). Retrieved February 25, 2023, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8878098/