Asiatic acid isolated from Centella asiatica inhibits TGF-β1-induced collagen expression in human keloid fibroblasts via PPAR-γ activation

The Relationship between Proliferative Scars and Endothelial Function in Surgically Revascularized Patients

BACKGROUND

Proliferative scars are benign fibrotic proliferations which demonstrate abnormal wound healing in response to skin injuries. As postulated in the "response to injury hypothesis", atherosclerosis is also triggered by an endothelial injury. Keloid and atherosclerotic processes have many pathophysiological and cytological features in common.

AIMS

In this study, we investigated the relationship between proliferative scars and endothelial function in surgically revascularized patients. We aimed to test the hypothesis that atherosclerosis is a wound healing abnormality.

STUDY DESIGN

Cross-sectional study.

METHODS

Consecutive patients who were admitted to the cardiology outpatient clinic with a history of coronary artery bypass grafting operation were evaluated. Thirty-three patients with proliferative scars at the median sternotomy site formed the keloid group, and 36 age- and sex-matched patients with no proliferative scar at the median sternotomy site formed the control group. Endothelial function was evaluated by flow-mediated vasodilatation of the brachial artery via ultrasonograhic examination.

RESULTS

There is no signicant difference according to the demographic data, biochemical parameters, clinical parameters and number of grafts between keloid and control groups. Endothelial-dependent vasodila-tory response was lower in the keloid group than the control group (9.30±3.5 and 18.68±8.2, respectively; p=0.001).

CONCLUSION

This study showed that endothalial dysfunction, which is strongly correlated with atherosclerosis, was more prominent in patients with proliferative scars. As proliferative scars and atherosclerosis have many features in common, we might conclude that atherosclerosis is a wound healing abnormality.

Neuroprotective effects of madecassoside against focal cerebral ischemia reperfusion injury in rats

Madecassoside, a triterpenoid derivative isolated from Centella asiatica, exhibits anti-inflammatory and antioxidant activities. We investigated its neuroprotective effect against ischemia-reperfusion (I/R) injury in cerebral neurons in male Sprague-Dawley rats. Madecassoside (6, 12, or 24mg/kg, i.v.) was administered 1h after the start of reperfusion, and neurological deficit score and infarct volume were evaluated 24h later. Neuronal apoptosis was assessed by performing terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL) staining, and pathological brain damage was estimated by performing hematoxylin and eosin staining. Serum levels of malondialdehyde, superoxide dismutase activity, reduced glutathione levels, and nitric oxide levels were also determined. mRNA and protein expression of pro-inflammatory cytokines (Interleukin-1β/6, and tumor necrosis factor-α) were measured by real-time RT-PCR and ELISA, respectively; NF-κB p65 expression was determined by western blotting. Madecassoside significantly reduced brain infarct area, resolved neurological deficit, and ameliorated neuronal apoptosis. It also significantly reduced the levels of malondialdehyde and nitric oxide, and augmented the antioxidant activity in rats subjected to cerebral I/R. Moreover, the levels of pro-inflammatory cytokines and NF-κB p65 significantly reduced after madecassoside treatment. These results indicate that madecassoside is neuroprotective and may be useful in reducing the damage caused by stroke.