Potential Biological Properties of Lycopene in a Self-Emulsifying Drug Delivery System

Abstract

In recent years, lycopene has been highlighted due to its antioxidant and anti-inflammatory properties, associated with a beneficial effect on human health. The aim of this study was to advance the studies of antioxidant and anti-inflammatory mechanisms on human keratinocytes cells (HaCaT) of a self-emulsifying drug delivery system (SEDDS) loaded with lycopene purified from red guava (nanoLPG). The characteristics of nanoLPG were a hydrodynamic diameter of 205 nm, a polydispersity index of 0.21 and a zeta potential of -20.57, providing physical stability for the nanosystem. NanoLPG demonstrated antioxidant capacity, as shown using the ORAC methodology, and prevented DNA degradation (DNA agarose). Proinflammatory activity was evaluated by quantifying the cytokines TNF-α, IL-6 and IL-8, with only IL-8 showing a significant increase (p < 0.0001). NanoLPG showed greater inhibition of the tyrosinase and elastase enzymes, involved in the skin aging process, compared to purified lycopene (LPG). In vitro treatment for 24 h with 5.0 µg/mL of nanoLPG did not affect the viability of HaCaT cells. The ultrastructure of HaCaT cells demonstrated the maintenance of morphology. This contrasts with endoplasmic reticulum stresses and autophagic vacuoles when treated with LPG after stimulation or not with LPS. Therefore, the use of lycopene in a nanoemulsion may be beneficial in strategies and products associated with skin health.

Keywords: antioxidant; carotenoid; guava fruit; nanomedicine; skin care.

Figure 1

Electrophoresis results and the corresponding graphic of antioxidant activity in the prevention of DNA oxidation by H₂O₂ (A₁,A₂) and H₂O₂/FeCl₃ (B₁,B₂) and the pro-oxidant effect in the absence (C₁,C₂) and presence (D₁,D₂) of iron cations of the different concentrations (0.5, 1 and 2 mg/mL (v/v)) of nanoLPG and LPG). (C+) DNA solution; (C−) DNA solution + degradation system; (1, 2 and 3) nanoLPG at 2, 1 and 0.5 mg/mL (v/v), respectively; (1′, 2′ and 3′) LPG at 2, 1 and 0.5 mg/mL (v/v), respectively. The data represent the mean ± SD from one experiment.

Figure 2

Cytotoxicity of free LPG and nanoLPG after 24 h. (A) HaCaT and (B) L929 (NCTC) cell viability. Bars represent cell viability, measured by the PrestoBlue assay (ThermoFisher), in percentage after treatments at the indicated concentrations. The data represent the mean ± SD of one independent experiment in quintuplicate. ** p < 0.01 and **** p < 0.0001. Treatment compared to untreated control.

Figure 3

Action of free LPG and nanoLPG on the production of TNF-α (A), IL-6 (B) and IL-8 (C) in HaCaT cells. The left part of all graphs corresponds to the non-stimulated cell response, and the right is related to the anti-inflammatory effect. The production of TNF-α, IL-6 and IL-8 was determined by ELISA. The data represent the mean ± SD of one independent experiment in duplicate. **** p < 0.0001. Treatment compared to control and control LPS.

Figure 4

Scanning electron microscopy of HaCaT cells after 24 h of treatment with 5 µg/mL of nanoLPG (A,B) or LPG (C,D), in the absence (A,C) or presence (B,D) of lipopolysaccharides (LPS) at 1 µg/mL. Arrows indicate extensions on the cell surface.

Figure 5

Transmission electron microscopy of HaCaT cells. Control cells (A); insect cytoplasmic region showing the Golgi complex. After treatment, for 24 h, with 5 µg/mL of nanoLPG (B) or LPG (C). (m) mitochondria, (n) nucleus, (g) Golgi complex, (er) endoplasmic reticulum, (l) lysosome, (v) autophagy vacuole, and (arrow) vesicle with nanoLPG.

Figure 6

Transmission electron microscopy of HaCaT cells after 24 h of treatment with lipopolysaccharides (LPS) at 1 µg/mL (A). Cell treatment with 5 µg/mL of nanoLPG (B) or LPG (C) in the presence of lipopolysaccharides (LPS) at 1 µg/mL. (m) mitochondria, (n) nucleus), (g) Golgi complex, (er) endoplasmic reticulum, and (l) lysosome.