Honey and epithelial to mesenchymal transition in wound healing: An evidence-based review

Combination therapy with miR34a and doxorubicin synergistically inhibits Dox-resistant breast cancer progression via down-regulation of Snail through suppressing Notch/NF-κB and RAS/RAF/MEK/ERK signaling pathway

Resistance to breast cancer (BCa) chemotherapy severely hampers the patient's prognosis. MicroRNAs provide a potential therapeutic prospect for BCa. In this study, the reversal function of microRNA34a (miR34a) on doxorubicin (Dox) resistance of BCa and the possible mechanism was investigated. We found that the relative level of miR34a was significantly decreased in Dox-resistant breast cancer cell MCF-7 (MCF-7/A) compared with Dox-sensitive MCF-7 cells. Transfection with miR34a significantly suppressed the invasion, migration, adhesion of MCF-7/A cells without inhibiting their growth obviously. The combination of miR34a and Dox could significantly inhibit the proliferation, migration, invasion and induce the apoptosis of MCF-7/A cells. The synergistic effect of this combination on resistant MCF-7/A cells has no obvious relation with the expressions of classical drug-resistant proteins P-GP, MRP and GST-π, while closely related with the down-regulation on TOP2A and BCRP. Moreover, we found both protein and mRNA expression of Snail were significantly up-regulated in MCF-7/A cells in comparison with MCF-7 cells. Transfection with small interfering RNA (siRNA) of Snail could inhibit the invasion, migration and adhesion of drug-resistant MCF-7/A cells, while high-expression of Snail could remarkably promote the invasion, migration and adhesion of MCF-7 cells, which might be related with regulation of N-cadherin and E-cadherin. Transfection with miR34a in MCF-7/A cells induced a decrease of Snail expression. The potential binding sites of miR34a with 3' UTR of Snail were predicted by miRDB target prediction software, which was confirmed by luciferase reporter gene method. Results showed that the relative activity of luciferase was reduced in MCF-7/A cells after co-transfection of miR34a and wild type (wt)-Snail, while did not change by co-transfection with miR34a and 3' UTR mutant type (mut) Snail. Combination of miR34a and Dox induced a stronger decrease of Snail in MCF-7/A cells in comparison to miR34a or Dox treatment alone. What' more, for the first time, we also found miR34a combined with Dox could obviously inhibit the expression of Snail through suppressing Notch/NF-κB and RAS/RAF/MEK/ERK pathway in MCF-7/A cells. In vivo study indicated that combination of miR34a and Dox significantly slowed down tumor growth in MCF-7/A nude mouse xenograft model compared with Dox alone, which was manifested by the down-regulation of Snail and pro-apoptosis effect in tumor xenografts. These results together underline the relevance of miR34a-driven regulation of Snail in drug resistance and co-administration of miR34a and Dox may produce an effective therapy outcome in the future in clinic.

Augmented Graphene Quantum Dot-Light Irradiation Therapy for Bacteria-Infected Wounds

This paper proposes a highly efficient antibacterial system based on a synergistic combination of photodynamic therapy, photothermal therapy, and chemotherapy. Chitosan oligosaccharide functionalized graphene quantum dots (GQDs-COS) with short-term exposure to 450 nm visible light are used to promote rapid healing in bacteria-infected wounds. The GQDs undergo strong photochemical transformation to rapidly produce radical oxygen species and heat under light illumination, while the COS has an innate antimicrobial ability. Moreover, the positively charged GQDs-COS can easily capture bacteria via electrostatic interactions and kill Gram-positive and Gram-negative bacteria by multivalent interactions and synergistic effects. The antibacterial action of this nanocomposite causes irreversible damage to outer and inner bacterial membranes, resulting in cytoplasm leakage and death. The system has good hemocompatibility and low cytotoxicity and can improve the healing of infected wounds, as demonstrated by the examination of pathological tissue sections and inflammatory markers. These results suggest that GQDs anchored with bioactive molecules are a potential photo-activated antimicrobial strategy for anti-infective therapy.

Bee Products in Dermatology and Skin Care

Honey, propolis, bee pollen, bee bread, royal jelly, beeswax and bee venom are natural products which have been used in medicine since ancient times. Nowadays, studies indicate that natural bee products can be used for skin treatment and care. Biological properties of these products are related to flavonoids they contain like: chrysin, apigenin, kaempferol, quercetin, galangin, pinocembrin or naringenin. Several pharmacological activities of phenolic acids and flavonoids, and also 10-hydroxy-trans-2-decenoic acid, which is present in royal jelly, have been reported. Royal jelly has multitude of pharmacological activities: antibiotic, antiinflammatory, antiallergenic, tonic and antiaging. Honey, propolis and pollen are used to heal burn wounds, and they possess numerous functional properties such as: antibacterial, anti-inflammatory, antioxidant, disinfectant, antifungal and antiviral. Beeswax is used for production of cosmetics and ointments in pharmacy. Due to a large number of biological activities, bee products could be considered as important ingredients in medicines and cosmetics applied to skin.

Effect of Nigella sativa and its bioactive compound on type 2 epithelial to mesenchymal transition: a systematic review

BACKGROUND

Nigella sativa or commonly known as black seed or black cumin is one of the most ubiquitous complementary medicine. Epithelial to mesenchymal transition (EMT) of type 2 is defined by the balance between wound healing and tissue fibrosis, which is dependent to the state of inflammation. This systematic review is conducted to provide an overview regarding the reported effect of Nigella sativa and its bioactive compound on the type 2 EMT.

METHODS

A search was done in EBSCOHOST, OVID and SCOPUS database to obtain potentially relevant articles that were published between 1823 and August 2019. This review includes studies that focus on the effect of Nigella sativa and its bioactive compound on the events related to type 2 EMT.

RESULTS

A total of 1393 research articles were found to be potentially related to the effect of Nigella sativa and its bioactive compound, thymoquinone on Type 2 EMT. After screening was done, 22 research articles met inclusion criteria and were included in this review. Majority of the studies, reported better wound healing rate or significant prevention of tissue inflammation and organ fibrosis following Nigella sativa or thymoquinone treatments. In terms of wound healing, studies included reported progression of EMT related pathological changes after treatment with Nigella sativa or thymoquinone. Alternatively, in terms of fibrosis and inflammation, studies included reported reversal of pathological changes related to EMT after treatment with Nigella sativa or thymoquinone.

CONCLUSION

Through this review, Nigella sativa and thymoquinone have been associated with events in Type 2 EMT. They have been shown to promote wound healing, attenuate tissue inflammation, and prevent organ fibrosis via regulation of the EMT process.

Modulation of Epithelial to Mesenchymal Transition Signaling Pathways by Olea Europaea and Its Active Compounds

Epithelial-mesenchymal transition (EMT) is a significant dynamic process that causes changes in the phenotype of epithelial cells, changing them from their original phenotype to the mesenchymal cell phenotype. This event can be observed during wound healing process, fibrosis and cancer. EMT-related diseases are usually caused by inflammation that eventually leads to tissue remodeling in the damaged tissue. Prolonged inflammation causes long-term EMT activation that can lead to tissue fibrosis or cancer. Due to activation of EMT by its signaling pathway, therapeutic approaches that modulate that pathway should be explored. Olea europaea (OE) is well-known for its anti-inflammatory effects and abundant beneficial active compounds. These properties are presumed to modulate EMT events. This article reviews recent evidence of the effects of OE and its active compounds on EMT events and EMT-related diseases. Following evidence from the literature, it was shown that OE could modulate TGFβ/SMAD, AKT, ERK, and Wnt/β-catenin pathways in EMT due to a potent active compound that is present therein.