Tualang Honey Improves Human Corneal Epithelial Progenitor Cell Migration and Cellular Resistance to Oxidative Stress In Vitro

Abstract

Stem cells with enhanced resistance to oxidative stress after in vitro expansion have been shown to have improved engraftment and regenerative capacities. Such cells can be generated by preconditioning them with exposure to an antioxidant. In this study we evaluated the effects of Tualang honey (TH), an antioxidant-containing honey, on human corneal epithelial progenitor (HCEP) cells in culture. Cytotoxicity, gene expression, migration, and cellular resistance to oxidative stress were evaluated. Immunofluorescence staining revealed that HCEP cells were holoclonal and expressed epithelial stem cell marker p63 without corneal cytokeratin 3. Cell viability remained unchanged after cells were cultured with 0.004, 0.04, and 0.4% TH in the medium, but it was significantly reduced when the concentration was increased to 3.33%. Cell migration, tested using scratch migration assay, was significantly enhanced when cells were cultured with TH at 0.04% and 0.4%. We also found that TH has hydrogen peroxide (H2O2) scavenging ability, although a trace level of H2O2 was detected in the honey in its native form. Preconditioning HCEP cells with 0.4% TH for 48 h showed better survival following H2O2-induced oxidative stress at 50 µM than untreated group, with a significantly lower number of dead cells (15.3±0.4%) were observed compared to the untreated population (20.5±0.9%, p<0.01). Both TH and ascorbic acid improved HCEP viability following induction of 100 µM H2O2, but the benefit was greater with TH treatment than with ascorbic acid. However, no significant advantage was demonstrated using 5-hydroxymethyl-2-furancarboxaldehyde, a compound that was found abundant in TH using GC/MS analysis. This suggests that the cellular anti-oxidative capacity in HCEP cells was augmented by native TH and was attributed to its antioxidant properties. In conclusion, TH possesses antioxidant properties and can improve cell migration and cellular resistance to oxidative stress in HCEP cells in vitro.

Randomised controlled trial of topical antibacterial Manuka (Leptospermum species) honey for evaporative dry eye due to meibomian gland dysfunction

“…Both honey products were superior to the control in reducing interpalpebral ocular surface epitheliopathy with Optimel 16 per cent drops being significantly more effective (Figure and Table ). This improvement in superficial epitheliopathy adds to the growing body of evidence from clinical trials, retrospective reviews, case reports, animal models of wound healing and in vitro studies that honeys from a variety or floral sources and geographic locations and in varying concentrations can reduce corneal epitheliopathy, and promote corneal epithelialisation . The immunomodulatory activity of honey is highly complex because of the involvement of multiple quantitatively variable compounds among honeys of different origins …”

Biocompatible Nutmeg Oil-Loaded Nanoemulsion as Phyto-Repellent

“…(1:1000) was auto injected in the splitless mode. The constituents in the essential oil were identified by comparison with the National Institute of Standard and Technology mass spectral library and presented as relative percentage of the total peak (Tan et al, 2014;Lim et al, 2015).…”

Malaysian Tualang Honey and Its Potential Anti-Cancer Properties: A Review

“…High performance liquid chromatography (HPLC) has shown the presence of a number of phenolic acids, including gallic, syringic, benzoic, transcinnamic, p-coumaric acids and flavonoid compounds such as catechin and kaempferol in MTH (Khalil et al 2011). On the other hand, Tan et al (2014) reported MTH contains 5-(hydroxymethyl)-2-furancarboxaldehyde, 3-furaldehyde, 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl-, phenylacetaldehyde, 2-furanmethanol and maltol which known to contribute antioxidant properties of this honey. Due to a number of phytochemical constituents, accumulating evidence supports that MTH possesses multiple biological activities, including antimicrobial, anti-inflammatory, antioxidant, antimutagenic, antitumor properties and also promotes wound healing (Attia et al 2008;Fauzi et al 2011;Ghashm et al 2010;Halima et al 2010;Mohamed et al 2010;Nasir et al 2010 (MCF-7).…”