A novel peptide hydrogel of metal ion clusters for accelerating bone defect regeneration.

In the absence of adequate treatment, effective bone regeneration remains a great challenge. Exploring hydrogels with properties of excellent bioactivity, stability, non-immunogenicity, and commercialization is an important step to develop hydrogel-based bone regeneration materials. In this study, we engineered a self-assembled chelating peptide hydrogel loaded with an osteogenic metal ion cluster extracted from the processed pyritum decoction, including Fe2+, Cu2+, Zn2+, Mn2+, Mg2+, and Ca2+ ions, named processed pyritum hydrogel (PPH). We demonstrated that as a reservoir of beneficial metal ion clusters in bone regeneration, PPH has been shown to regulate a variety of genes in the process of bone regeneration. These genes are mainly involved in extracellular matrix synthesis, cell adhesion and migration, cytokine expression, antimicrobial and inflammation. Therefore, PPH accelerated the progress of various bone healing stages, and shortened the bone healing cycle by 4 weeks. Our investigation outcomes showed that the engineered metal ion cluster hydrogel is a novel, simple, and commercializable bone-regenerating hydrogel with potential clinical use.

[Comparative study of penetration-enhancing effect in vitro of cinnamon oil and cinnamaldehyde on ibuprofen].

To compare the penetration-enhancing effect of cinnamon oil and its main components (cinnamaldehyde) on ibuprofen and their self-percutaneous absorption behavior in vitro. Firstly, cinnamon oil was extracted by steam distillation, then the compositions were analyzed by gas chromatography mass spectrometry (GC-MS) and the cinnamaldehyde content in cinnamon oil was determined by high performance liquid chromatography (HPLC). With azone as positive control, ibuprofen as model drug, cinnamon oil and cinnamaldehyde as penetration enhancers (PE) were prepared and administered to the SD rat's abdominal skin. The penetration-enhancing effects of cinnamon oil and cinnamaldehyde and their own transdermal absorption properties were compared. The results showed that yield of cinnamon oil was (3.55±0.36)% (n=3), and the cinnamaldehyde content in cinnamon oil was (73.48±0.21)% (n=3). As compared with blank group, the enhancing rate (ER) of cinnamon oil, cinnamaldehyde, and azone was 3.56, 1.13, 2.47 respectively. The cumulative penetration rate of cinnamaldehyde in cinnamon oil and cinnamaldehyde monomer in 24 h was (63.30±0.98)%, (51.03±3.34)% (n=4) respectively. The penetration-enhancing effect of cinnamon oil was significantly better than that of cinnamaldehyde, indicating the existence of muti-component synergy. The penetration rate of cinnamaldehyde in cinnamon oil was higher than that of cinnamaldehyde monomer, suggesting that a "pull effect" may be present.