ABSTRACT
Objective To investigate the heterogeneity of immunomodulatory function of exosomes secreted from human umbilical cord-derived mesenchymal stem cells(hUC-MSC).Methods Five different hUC-MSCs lines were isolated and cultured.Exosomes were isolated from the supernatant.The expression of specific surface markers CD9,CD63,CD81 and CD44 was detected by flow cytometry.The protein concentration of hUC-MSCs exosomes(hUC-MSCs-ex)was evaluated by the BCA assay.Concanavalin A and rhIL-2 stimulated umbilical cord blood mononuclear cells (UBMCs) from healthy donor were co-cultured at different concentrations of hUC-MSCs-ex from different cell lines for 72 h.The growth rate of UBMCs was detected by MTT assay.ELISA was used to test the levels of IFN-γ and TNF-α of the supernatants.The UBMCs co-cultured with hUC-MSCs were co-cultured with K562 cells at the ratio of 5∶1.The cytotoxic activity was calculated by MTT assay.Results hUC-MSCs-ex expressed CD9,CD63,CD81and CD44.Different hUC-MSCs lines had different regulating activities on the proliferation,secretion and killing ability of UBMCs.Conclusion hUC-MSCs-ex has heterogeneity of immunomodulatory function on UBMCs.
ABSTRACT
In order to reveal the treatment mechanism of Chinese medicine with the effect of activating blood and resolving putridity, we selected acetyl-11-keto-beta-boswellic acid (AKBA) and arsenic trioxide (ATO), the main monomeric components of frankincense and arsenolite which are two most commonly used Chinese medicine with effect of activating blood and resolving putridity. We combined AKBA and ATO as a compound, and explored its regulatory role in productions and activities of matrix metalloproteinase (MMP)-1, MMP-2 and MMP-9 in human skin fibroblasts (HSFbs) and human acute monocytic leukemia cell line THP-1 in inflammatory state.
ABSTRACT
Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases, which as a group can degrade essentially all extracellular matrix components. The proteolytic property of the MMPs is important during wound healing to remove debris and facilitate cell migration. Targeting towards the decreased MMPs activities is a new treatment strategy for healing chronic wounds. Salvia miltiorrhiza is a popular Chinese herb that could promote chronic ulcers healing for topical use. Salvianolic acid B (Sal B) is the most abundant bioactive component in Salvia miltiorrhiza. The research was designed to explore the inhibitory effects of Sal B on MMP-1, MMP-2 and MMP-9 activities.
ABSTRACT
AIM: To evaluate the effects of acetyl-11-keto-beta-boswellic acid (AKBA, a main active component from frankincense, one of the traditional Chinese herb for healing wounds) on the activities of matrix metalloproteinase(MMP)-1, MMP-2 and MMP-9.METHODS: Pure human interstitial collagenase (MMP-1) or gelatinase A (MMP-2) was activated by p-aminophenylmercuric acetate (APMA), and was incubated with AKBA for 1 h. The activities of the enzymes were observed by quenched fluorescent substrate. The lysates of rat polymorphonuclear neutrophils [PMNs, rich in gelatinase B (MMP-9)] was incubated with AKBA for 1 h, and activity of MMP-9 was tested by gelatin zymography. Three cell models: activated human dermal fibroblasts by TNF-α, activated THP-1 cells by PMA and fibroblasts-THP-1 co-culture system were established. AKBA was cultured with these cell models for 24 h. The levels of MMP-1, MMP-2 and MMP-9 in the cell culture supernatants were tested by ELISA and activities of MMP-2 and MMP-9 were tested by gelatin zymography assays.RESULTS: AKBA dose-dependently inhibited the activities of human MMP-1 and MMP-2 at the range of 0.1-0.8 mmol/L, with 50% inhibitory concentration (IC50) of 0.18 mmol /L and 0.27 mmol/L, respectively. In the range of 0.05-0.85 mmol/L, AKBA inhibited the MMP-9 activity (P<0.01). Although AKBA promoted fibroblasts to secrete MMP-2, the production of MMP-9 by THP-1 was inhibited. In the cell co-culture system, the inhibitory effects on MMP-1, MMP-2 and MMP-9 productions were also observed.CONCLUSION: AKBA, as a bioactive component of frankincense, has an inhibitory effect on MMPs production and activities, indicating the possible mechanism for healing chronic wounds by frankincense.