# Anti-inflammatory potential of goldenberry-derived exosome-like nanoparticles in macrophage polarization

## TL;DR

Goldenberry nanoparticles reduce inflammation by shifting immune cells from harmful M1 to healing M2 types.

## Contribution

Isolation and characterization of GDEN from goldenberry and their anti-inflammatory effects on macrophage polarization.

## Key findings

- GDEN reduced nitric oxide production in LPS-induced macrophages at 40 μg/ml.
- GDEN increased M2 macrophage markers at 20 μg/ml, promoting anti-inflammatory polarization.
- GDEN were non-toxic to macrophage cells up to 60 μg/ml and were internalized by the cells.

## Abstract

Objective: Overpopulated M1 macrophages can trigger chronic inflammation. Plant-derived exosome-like nanoparticles have been reported to show beneficial bioactivities. Aim: To isolate PDEN from goldenberry fruits and evaluate its anti-inflammatory potential in macrophage polarization. Methods: GDEN were isolated by centrifugation and precipitation methods. LPS-induced RAW 264.7 cells were treated with GDEN before being evaluated with nitric oxide production assay and flow cytometry of CD80 and CD209. Results: GDEN averaged 227.7 nm in size and spherical-shaped. GDEN 40 μg/ml decreased NO production in LPS-induced cells. Flow cytometry showed that CD209 (M2 marker) positive cells were up-regulated after being treated with 20 μg/ml GDEN. Conclusion: GDEN showed anti-inflammatory potential through the ability to reduce M1 macrophages product and promote M2 polarization.

During inflammation, there are immune cells called macrophages which can act in two different ways. They are M1 cells which drive inflammation and M2 cells which resolve inflammation. The imbalance of M1 and M2 cells can be harmful to the body. For example, having too many M1 macrophages will cause chronic inflammation. Nano-sized particles found in plants are known to have some benefits as future drugs. They have good biocompatibility, can be produced in large quantities and show various bioactivities. Goldenberry has been used as an herb and is known to have good effects on human health, like reducing inflammation. In this study, nanoparticles from goldenberry fruits, also known as goldenberry-derived exosome-like nanoparticles (GDEN), were successfully extracted using a chemical, polyethylene glycol (PEG) 6000. GDEN showed no harmful effect on mice macrophage cells (RAW 264.7) and had been successfully taken inside by the cells. GDEN also showed reducing inflammation potential. This was supported by the decrease of M1 cell product and the increase of M2 cell marker. Hence, GDEN are worthy to be studied further for its usage to treat inflammation and other related health problems.

GDEN and Macrophage Polarization (Credit: BioRender).

The imbalance of M1-M2 proportion can cause several disadvantages to human body and PDEN have been reported to show an effect on macrophage polarization.

GDEN were successfully isolated from Physalis peruviana fruits by centrifugation method combined with precipitation using PEG6000 12%.

Characterization by PSA and TEM showed that GDEN averaged 227.7 nm in size and spherical-shaped.

GDEN were not cytotoxic to RAW 264.7 cells until concentration of 60 μg/ml, suggesting its advantage of in vitro biocompatibility.

GDEN had been successfully internalized by RAW264.7 during 2 h incubation period and internalization was enhanced with longer incubation period.

Treatment with 40 μg/ml GDEN was able to decrease NO production on LPS-induced cells significantly compared with other GDEN concentrations, indicating the ability of GDEN to suppress inflammation.

Tendency to decrease M1 population was observed on LPS-induced cells after being treated with GDEN although it was not statistically significant.

Treatment with 20 μg/ml GDEN gave the highest M2 population on LPS-induced cells, thus supporting GDEN anti-inflammatory potential.

GDEN showed anti-inflammatory potential by decreasing M1 product and M1 population, along with promoting M2 polarization when treated with 20 μg/ml GDEN.