Research progress of different mechanical stimulation regulating chondrocytes metabolism / 生物医学工程学杂志

As a kind of mechanical effector cells, chondrocytes can produce a variety of physical and chemical signals under the stimulation of multiaxial load

Phenotypic maintenance of chondrocytes in vitro under tensile stress enhanced by the extract of clematis chinensis / 中国组织工程研究

BACKGROUND: Mechanical load is crucial for the degeneration of chondrocytes and the development of osteoarthritis. Clematis chinensis can improve the inflammatory microenvironment of osteoarthritis, but its effect on mechanical load-induced degeneration of chondrocytes has not been elucidated. OBJECTIVE: To study the effect and mechanism of the extracts of Clematis chinensis on the degenerative changes of chondrocytes induced by intermittent cyclic mechanical tension (ICMT) in vitro. METHODS: Chondrocytes of the rabbit knee joint were isolated by type II collagenase digestion method and identified by Alcian blue staining. There were five groups in the experiment: Blank group, ICMT group, high-, medium- and low-dose Clematis chinensis groups. There was no intervention in the blank group, and the other groups were subjected to ICMT (10% tensile strength, 0.5 Hz, 8 hours per day, for a total of 2 days) for inducing chondrocyte degeneration. Three Clematis chinensis groups were concurrently given 0.5, 1, 2 g/L extracts of Clematis chinensis, respectively. The intervention time was 48 hours. Cell counting kit-8 assay was used for detection of chondrocyte proliferation. FITC-phalloidin staining was used for observation of cytoskeleton morphology. Real-time quantitative PCR and western blot assay were used for determination of collagen type II, matrix metalloproteinase 13, and transforming growth factor β at protein and gene levels, respectively. RESULTS AND CONCLUSION: (1) Compared with the blank group, the cytoskeleton of chondrocytes stimulated by ICMT was long- stretched, the proliferation activity of chondrocytes decreased, and the expressions of collagen type II and transforming growth factor β were down-regulated, while the expression of matrix metalloproteinase 13 was up-regulated. (2) Compared with the ICMT group, the extract of Clematis chinensis could promote the proliferation of chondrocytes, up-regulate the expressions of transforming growth factor β and collagen II, and down-regulate the expression of matrix metalloproteinase 13 in a concentration-dependent manner. To conclude, the extract of Clematis chinensis can inhibit the catabolism of chondrocyte induced by ICMT through regulating the expression of transforming growth factor β, promote the synthesis of extracellular matrix of chondrocytes, and maintain the phenotypic stability of chondrocytes.

Research progress on signaling molecules involved in articular cartilage repair / 生物医学工程学杂志

After the articular cartilage injury, the metabolic level is increased during the progressive degeneration, the chondrocytes secrete a variety of inflammatory factors, and the original cell phenotype is gradually changed. For a long time, a large number of researchers have done a lot of researches to promote anabolism of chondrocytes and to maintain the stability of chondrocyte phenotype. There are many molecular signaling pathways involved in the process of promoting cartilage repair. This review focuses on the key signaling molecules in articular cartilage repair, such as transforming growth factor-beta and bone morphogenetic protein, and reveals their roles in the process of cartilage injury and repair, so that researchers in related fields can understand the molecular mechanism of cartilage injury and repair widely and deeply. Based on this, they may find promising targets and biological methods for the treatment of cartilage injury.

Research progress in mechanism, diagnosis and treatment of neurogenic bowel dysfunction after spinal cord injury / 中华创伤杂志

Neurogenic bowel dysfunction (NBD) manifested as constipation and fecal incontinence often occurs after spinal cord injury (SCI).NBD affects patients' quality of life and is an urgent clinical problem to be solved.The mechanism of NBD is related to central and autonomic nervous system dysfunction,intestinal nervous system dysfunction,changes in intestinal microorganism composition and abnormal content of neurotransmitters.The evaluation method of NBD is mainly based on scoring and imaging,which lacks unified criteria,and the treatment method for NBD is the combination of traditional Chinese and Western medicine.The author summarizes the mechanism,evaluation method,treatment and nursing of NBD in order to provide new insight into these aspects to improve clinical efficacy.