Effects of Dendrobium Polysaccharides on the Functions of Human Skin Fibroblasts and Expression of Matrix Metalloproteinase-2 under High-Glucose Conditions

Abstract

The effects of Dendrobium polysaccharides (PDC) on the functions of human skin fibroblasts (HSFs) and expression of matrix metalloproteinase-2 under high-glucose conditions and exploration of the underlying mechanism remain unclear. We used the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis and flow cytometry to evaluate the cell viability and apoptosis. The collagen levels were determined by the Sircol™ Collagen Assay. Real-time quantitative polymerase chain reaction (RT-PCR) was used to detect the expression of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase inhibitor (TIMP-2) mRNA. We found the following: (1) under the high-glucose condition, the HSF cell viability, the expression of TIMP-2 mRNA, and the collagen levels were reduced, while the apoptosis rate and the expression of MMP-2 mRNA increased ( P < 0.05 ). (2) In the high-glucose + PDC group, the PDC reversed the changes in the collagen level, viability, and apoptosis rate of the HSF cells caused by high glucose, with the expression of protein and TIMP-2 mRNA increased and the level of MMP-2 mRNA decreased ( P < 0.05 ). This is the first time attempting to reveal that PDC can exhibit protective effects on HSF under high-glucose conditions, which may be related to the upregulation of the TIMP-2 expression and inhibition of the MMP-2 expression.

Targeting matrix metalloproteases in diabetic wound healing

“…Recently, these studies revealed that PDC at the concentrations of 100, 200, as well as 400 mg/mL elevates the level of COL, improves the viability of human skin fibroblasts, suppresses the cell apoptosis induced by HG, accompanied by the elevation of TIMP-2 and reduction of MMP-2. Therefore, these results confirmed that PDC can display protective effects on diabetic ulcer in vitro, and the mechanism may be related to the modulation of TIMP-2 and MMP-2, which provides a new idea for the prevention and treatment of diabetic skin ulcer or wound (98). However, further in vivo researches are required to clarify the activity of PDC against diabetic wound healing.…”

Extraction, Characterization, and Structure of a Novel Heteropolysaccharide from Lepidium sativum and Its Effects on Wound Healing in Diabetic Rats

“…This finding is in accordance with those obtained in previous research, where it has been reported that the Morin-incorporated polysaccharide-protein hydrogel accelerates diabetic wound healing in Wistar rats [ 39 ]. In addition, Li et al [ 43 ] demonstrated that polysaccharides extracted from Dendrobium candidum could be a potential candidate as wound healing-accelerating agents thanks to their incredible wound healing properties in both in vitro and in vivo experiments.…”

Regulation of Dendrobium Polysaccharides on Proliferation and Oxidative Stress of Human Umbilical Vein Endothelial Cells in the High Glucose Environment

“…Set the temperature constantly of the water bath to 37°C for 40 min, add the color reagent and mix well, pour it into a 1 cm optical path cuvette after 10 min, adjust to zero with distilled water, and compare the color with a microplate reader at a wave length of 550 nm. According to the formula SOD activity ðU/mgprotÞ = ½ðcontrol tube − measurement tubeÞ/control tube ÷ 50% × ðtotal volume of reaction solution /sampling amountÞ ÷ protein content in tissue ðmgprot/mLÞ, to calculate SOD activity, no clear sample is added to the control tube, and the others are the same as the measurement tube [13][14][15].…”