Targeting matrix metalloproteases: A promising strategy for herbal medicines to treat rheumatoid arthritis.

As a type of metalloproteinase, matrix metalloproteinases (MMPs) can be divided into collagenase, gelatinase, stromelysins, membrane-type (MT)-MMPs and heterogeneous subgroups according to their structure and function. MMP contents in the human body are strictly regulated, and their synthesis, activation and inhibition processes should be kept in a certain balance; otherwise, this would result in the occurrence of various diseases. Rheumatoid arthritis (RA) is a known immune-mediated systemic inflammatory disease that is affected by a variety of endogenous and exogenous factors. In RA development, MMPs act as important mediators of inflammation and participate in the degradation of extracellular matrix substrates and digestion of fibrillar collagens, leading to the destruction of joint structures. Interestingly, increasing evidence has suggested that herbal medicines have many advantages in RA due to their multitarget properties. In this paper, literature was obtained through electronic databases, including the Web of Science, PubMed, Google Scholar, Springer, and CNKI (Chinese). After classification and analysis, herbal medicines were found to inhibit the inflammatory process of RA by regulating MMPs and protecting joint structures. However, further preclinical and clinical studies are needed to support this view before these herbal medicines can be developed into drugs with actual application to the disease.

[Responses of spatial distribution pattern of the dominant population Artemisia ordosica to enclosure restoration in desert steppe.] / è’æ¼ è‰åŽŸä¼˜åŠ¿ç§ç¾¤æ²¹è’¿ç©ºé—´åˆ†å¸ƒæ ¼å±€å¯¹å°è‚²æ¢å¤çš„å“åº”.

Shrubs play an important role in maintaining biodiversity, stability and ecological service in grassland. Exploring the effects of enclosure on dominant shrub population can provide scientific guidance for grassland restoration and tending management. In this study, we investigated main growth characteristics and spatial distribution pattern of Artemisia ordosica population in four enclosed grasslands with duration of 0, 5, 15, and 25 years. The results showed that population density increased first and then decreased with time extension, and peaked after enclosed for 15 years, which was 3.7 times that of unenclosed plot. The crown and projected area showed opposite responses trend to that of density, which decreased by 31.7% and 52.3% after enclosed 15 years, respectively. The height decreased by 25.3% after 5 years of enclosure, and then increased gradually. Semi-variance function analysis showed that population distribution in all grasslands conformed to Gaussian model. The spatial variation decreased gradually in the early stage of enclosure, and then increased after enclosed for 15 years. Structure ratio in each plot was higher than 0.75, but nugget was relatively small, indicating that spatial autocorrelation of population was mainly affected by structural factors rather than random factors. Spatial distribution of A. ordosica population was patchy and striped. Enclosure reduced spatial variation of population at small scale. However, spatial heterogeneity and scale dependence of population enhanced after enclosed 25 years as plaque dissociating. Our findings suggest that enclosure duration is the key factor affecting plant growth and spatial distribution of dominant population in desert steppe. Long-term fencing enhances the spatial heterogeneity of dominant population. Appropriate human intervention should be carried out after 15 years of enclosure.

Treatment with nesiritide, a recombinant B-type natriuretic Peptide, reduces vascular remodeling following balloon-induced endothelial injuries in rabbits.

Re-stenosis or remodeling of coronary and peripheral arteries remains a major complication following balloon-angioplasty or stenting. This study was designed to investigate the effect of nesiritide, a recombinant B-type natriuretic peptide (BNP), on vascular remodeling following balloon-induced endothelial injuries. Twenty-eight male New Zealand rabbits were divided into nesiritide-treated (0.1 mg/kg/day, sc, for 4 weeks, n = 10), saline-treated control (n = 10) and sham-operated groups (n = 8). In the nesiritide and control groups, a balloon catheter was inserted to the right iliac artery to induce injuries. Vascular endothelial growth factor (VEGF) was measured by immunohistochemistry. The area under internal elastic membrane of the arterial wall (643.2 ± 134.1 vs 493.7 ± 139.3 µm(2), p < 0.05) and the area under external elastic membrane (1495.1 ± 204.9 vs 1265.9 ± 232.6 µm(2), p < 0.05) in the nesiritide group were greater than those in the control group, but were smaller than those in the sham-operated group (p < 0.05). The stenosis ratio was lower in the nesiritide group than in the control group (18.7 ± 7.7% vs 38.0 ± 8.3%, p < 0.01). Importantly, the VEGF expression rate was significantly lower in the nesiritide group than in the control group (42.2 ± 8.8% vs 56.1 ± 13.1%, p < 0.05), while there were no signs of VEGF expression in the non-injured arteries of the three groups. In conclusion, nesiritide treatment reduces the stenosis of the rabbit iliac artery following balloon-induced endothelial injuries probably by decreasing VEGF expression.