[Effect of panax notoginseng powder on pathological features and expressions of VEGF and its receptors of chronic subdural hematoma rabbits: an experimental study].

OBJECTIVE: To observe the effect of Panax notoginseng (PN) on pathological features in chronic subdural hematoma (CSDH) rabbits and its mechanisms. METHODS: A stable pathological animal model similar to CSDH in humans could be established using subdural injections of small number of blood through a subdural pre-catheter in rabbits. After successful modeling, 18 rabbits were randomly divided into the model group, the low dose PN group (0.125 g/kg), and the high dose PN group (0.250 g/kg), 6 in each group. Normal saline was given to rabbits in the model group, while PN power was given to those in the PN groups by gastrogavage for 6 successive days. Pathologic features of the hematoma outer membrane were observed by HE staining. The activity of SOD and the content of MDA in the hematoma outer membrane were examined by the colorimetric method. Expressions of CD31, CD34, and VEGF in the hematoma outer membrane were observed by immunohistochemical assay. Expressions of VEGF in the peripheral blood and the subdural hematoma were detected by enzyme-linked immunosorbent assay (ELISA). Expressions of VEGFR-1 and VEGFR-2 in the hematoma outer membrane were detected by Western blot. RESULTS: Compared with the model group, the inflammatory reaction was comparatively lessen and the proliferation of the fibrous tissue was relatively mature in the low and high dose PN groups. The activity of SOD increased (P < 0.05); expressions of CD31 and CD34 were reduced (P < 0.01); VEGF expression in the residual hematoma fluid decreased (P < 0.05) in the high dose PN group. Expressions of VEGF and VEGFR-2 were all reduced in the high and low dose PN groups (P < 0. 05, P < 0.01). Compared with the low dose PN group, expressions of CD31 and CD34 were reduced (P < 0.01), and the VEGFR-2 expression was also reduced (P < 0.05) in the high dose PN group. CONCLUSIONS: PN could promote the fibrous repairing of subdural hematoma in CSDH rabbits. It also lessened inflammation and oxidative injury of the hematoma outer membrane and reduced expressions of VEGF. The pathological angiogenesis could be reduced through influencing VEGFR-2 receptor pathways, which might be an important mechanism.

Effects of L-carnitine against oxidative stress in human hepatocytes: involvement of peroxisome proliferator-activated receptor alpha.

BACKGROUND: Excessive oxidative stress and lipid peroxidation have been demonstrated to play important roles in the production of liver damage. L-carnitine is a natural substance and acts as a carrier for fatty acids across the inner mitochondrial membrane for subsequent beta-oxidation. It is also an antioxidant that reduces metabolic stress in the cells. Recent years L-carnitine has been proposed for treatment of various kinds of disease, including liver injury. This study was conducted to evaluate the protective effect of L-carnitine against hydrogen peroxide (H2O2)-induced cytotoxicity in a normal human hepatocyte cell line, HL7702. METHODS: We analyzed cytotoxicity using MTT assay and lactate dehydrogenase (LDH) release. Antioxidant activity and lipid peroxidation were estimated by reactive oxygen species (ROS) levels, activities and protein expressions of superoxide dismutase (SOD) and catalase (CAT), and malondialdehyde (MDA) formation. Expressions of peroxisome proliferator-activated receptor (PPAR)-alpha and its target genes were evaluated by RT-PCR or western blotting. The role of PPAR-alpha in L-carnitine-enhanced expression of SOD and CAT was also explored. Statistical analysis was performed by a one-way analysis of variance, and its significance was assessed by Dennett's post-hoc test. RESULTS: The results showed that L-carnitine protected HL7702 cells against cytotoxity induced by H2O2. This protection was related to the scavenging of ROS, the promotion of SOD and CAT activity and expression, and the prevention of lipid peroxidation in cultured HL7702 cells. The decreased expressions of PPAR-alpha, carnitine palmitoyl transferase 1 (CPT1) and acyl-CoA oxidase (ACOX) induced by H2O2 can be attenuated by L-carnitine. Besides, we also found that the promotion of SOD and CAT protein expression induced by L-carnitine was blocked by PPAR-alpha inhibitor MK886. CONCLUSIONS: Taken together, our findings suggest that L-carnitine could protect HL7702 cells against oxidative stress through the antioxidative effect and the regulation of PPAR-alpha also play an important part in the protective effect.

[Effect of safflor yellow B on vascular endothelial cells injury induced by angiotensin-II].

This study is to investigate protective effect of safflor yellow B (SYB) against vascular endothelial cells (VECs) injury induced by angiotensin-II (Ang-II). VECs were cultured and divided into six groups: control group, Ang-II group, Ang-II + SYB (1 micromolL(-1)) group, Ang-II + SYB (10 micromolL(-1)) group, Ang-II + SYB (100 micromolL(-1)) group and Ang- II + verapamil (10 micromolL(-1)) group. Except control group, all of VECs in other groups were treated with Ang- II at the final concentration of 0.1 micromolL(-1). Mitochondria membrane potential (MMP) and free calcium concentration ([Ca2+]i) were measured by laser scanning confocal microscopy, and mitochondria complex IV activity was detected by BCA method. The levels of reactive oxygen species (ROS) in VECs were analyzed by fluorescence detector and apoptosis of VECs was observed by flow cytometer. Caspase 3 was determined by Western blotting method. Comparing with control group, Ang-II was able to increase [Ca2+]i and ROS level, decrease MMP level, inhibit complex IV activity and enhance caspase 3 activity in VECs, as a result, enhance apoptosis of VECs. But SYB could significantly reduce the result induced by Ang- II relying on different dosages (P < 0.05 or P < 0.01). SYB was able to eliminate the effect of Ang-II on VECs via regulating [Ca2+]i, mitochondrial structure and function and inhibiting apoptosis.