Oral administration of turmeric-derived exosome-like nanovesicles with anti-inflammatory and pro-resolving bioactions for murine colitis therapy

Abstract

Background: Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) characterized by diffuse inflammation of the colonic mucosa and a relapsing and remitting course. The current therapeutics are only modestly effective and carry risks for unacceptable adverse events, and thus more effective approaches to treat UC is clinically needed.

Results: For this purpose, turmeric-derived nanoparticles with a specific population (TDNPs 2) were characterized, and their targeting ability and therapeutic effects against colitis were investigated systematically. The hydrodynamic size of TDNPs 2 was around 178 nm, and the zeta potential was negative (- 21.7 mV). Mass spectrometry identified TDNPs 2 containing high levels of lipids and proteins. Notably, curcumin, the bioactive constituent of turmeric, was evidenced in TDNPs 2. In lipopolysaccharide (LPS)-induced acute inflammation, TDNPs 2 showed excellent anti-inflammatory and antioxidant properties. In mice colitis models, we demonstrated that orally administrated of TDNPs 2 could ameliorate mice colitis and accelerate colitis resolution via regulating the expression of the pro-inflammatory cytokines, including TNF-α, IL-6, and IL-1β, and antioxidant gene, HO-1. Results obtained from transgenic mice with NF-κB-RE-Luc indicated that TDNPs 2-mediated inactivation of the NF-κB pathway might partially contribute to the protective effect of these particles against colitis.

Conclusion: Our results suggest that TDNPs 2 from edible turmeric represent a novel, natural colon-targeting therapeutics that may prevent colitis and promote wound repair in colitis while outperforming artificial nanoparticles in terms of low toxicity and ease of large-scale production.

Keywords: NF-κB pathway; Nanotherapeutics; Oral administration; Turmeric-derived nanoparticles; Ulcerative colitis.

Fig. 1

Schematic illustration of turmeric-derived nanoparticles (TDNPs 2) isolation and targeted ulcerative colitis (UC) therapy via oral administration. A TDNPs 2 were isolated and purified from edible turmeric by ultracentrifugation and sucrose gradient centrifugation. B By oral administration, TDNPs 2 accumulated at inflamed colon and exerted UC therapeutic effect

Fig. 2

Characterization of TDNPs. A TDNPs were isolated and purified by sucrose gradient ultracentrifugation, band 1 from 8%/30% interface was named TDNPs 1, and band 2 from 30%/45% interface was named TDNPs 2. B Transmission Electron Microscopy (TEM) to characterize the morphology and size. C TDNPs were also identified by Atomic Force Microscopy (AFM). D Yields of TDNPs 1 and TDNPs 2 from turmeric were calculated and compared (n = 5). E Putative lipid species between TDNPs 1 and TDNPs 2 were compared

Fig. 3

TDNPs prevent LPS-induced macrophage inflammation. A–C mRNAs expression of pro-inflammatory cytokines, TNF-α, IL-6 and IL-1β, respectively (n = 5). D mRNA expression of HO-1 (n = 5)

Fig. 4

TDNPs 2 preferentially localized to the inflamed colon. A Digestive tract, mesenteric lymph nodes (MLN), and vital organs (Heart, liver, spleen, lung, kidney, and) were imaged by IVIS® Spectrum imaging system. B–D FACS was used to determine the population of cells to uptake DiO labeled TNDPs 2 (n = 3)

Fig. 5

Cellular uptake of TNDPs 2 by macrophage 264.7 and colon-26 cells. The cell nucleus was stained by DAPI (Blue), the cytoskeleton was stained by FITC-phalloidin (Green), and TDNPs 2 were labeled by lipophilic carbocyanine dye, DiL (Red), scale bar: 20 μm

Fig. 6

Oral administration of TDNPs 2 alleviated DSS-induced colitis. A Lipocalin-2 quantification (n = 5). B Colon inflammation was monitored by XenoLight RediJect inflammation probe via chemiluminescence imaging (n = 3). C Average radiance was captured and compared between groups (n = 5). D MPO quantification (n = 5). E Real-time PCR to quantify miRNA expression (n = 5), *p < 0.05, **p < 0.01, ***p < 0.001

Fig. 7

Histological stain to evaluate the protective effect of TDNPs 2 on colitis. A Representative H&E-stained colon. Inflammatory cell infiltration was indicated by arrowheads. B Colonic goblet cells were stained by Alcian blue. As goblet cells produce mucins, Alcian blue was used to highlight the goblet cell population. C E-cadherin expression was detected by immunofluorescence. Scale bar: 50 μm

Fig. 8

Oral administration of TDNPs 2 accelerated inflammation resolution of colitis. A ECIS wound healing assay. B Lcn-2 quantification (n = 5). C Spleen weight (n = 5). D Colon inflammation was monitored by XenoLight RediJect inflammation probe via chemiluminescence imaging. E Average radiance (n = 5). F MPO quantification (n = 5). G Real-time PCR to quantify miRNA expression (n = 5). *p < 0.05, ***p < 0.001 and ns represent no significant difference

Fig. 9

Biocompatibility evaluation of TDNPs 2. A Vital organs weights (n = 5). B Pro-inflammatory cytokines (n = 5). C Indicators reflected the physiological function of the liver were evaluated. D H&E staining, scale bar: 50 μm

Fig. 10

TDNPs 2 exerted a protective effect by inactivating the NF-κB pathway. A NF-κB activity evaluation (n = 5). B Phospho-NF-κB p65 expression was evaluated by ELISA assay (n = 5). C The translocation of NF-kB-p65 to the nucleus was assessed by immunofluorescence, scale bar = 10 μm. D NF-κB-RE-Luc transgenic mice was used to investigate NF-κB activity in vivo (n = 5). E NF-κB expression in the colon was evaluated by IHC