Protective effects of leonurine against ischemic stroke in mice by activating nuclear factor erythroid 2-related factor 2 pathway.

AIMS: Leonurine has been shown to trigger antioxidant responses during ischemic stroke, and nuclear factor erythroid 2-related factor 2 (Nrf-2) imparts protective effects against oxidative injury. The present study has determined that leonurine prevents ischemic injury of brain tissues via Nrf-2 pathway activation. METHODS: Male ICR mice and Nrf-2-/- mice were subjected to permanent middle cerebral artery occlusion (pMCAO) and received leonurine treatment at 2 hours after pMCAO by intraperitoneal injection. Neurological deficit scores as well as infarct volume were assessed to determine the neuroprotective role of leonurine. Nrf-2 was investigated using Western blotting and real-time polymerase chain reaction (RT-PCR) analysis to elucidate the neuroprotective mechanism of leonurine. Commercial kits were employed to determine reactive oxygen species (ROS), superoxide (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), malonaldehyde (MDA), and glutathione (GSH). Vascular endothelial growth factor (VEGF) was evaluated by Western blotting and RT-PCR analysis, and VEGF was localized using immunofluorescence. RESULTS: The application of leonurine on ICR mice resulted in an improvement in neurological deficit scores and a reduction in infarct volume. Leonurine upregulated nuclear Nrf-2 protein and increased total Nrf-2 protein expression and mRNA levels. Leonurine regulated SOD, MDA, CAT, GSH, and GSH-Px, and it significantly inhibited ROS production in ICR mice. Leonurine improved VEGF expression and increased VEGF expression in neurons, astrocytes, and endothelial cells. However, leonurine had no obvious beneficial effects on Nrf-2-/- mice. CONCLUSIONS: Leonurine exerted neuroprotective effects, promoted antioxidant responses, and upregulated VEGF expression by activating the Nrf-2 pathway.

[Observation on the leptin level in the subcutaneous tissues of the high temperature reaction zone along the abdominal gallbladder Meridian in rabbits with cholecystitis].

OBJECTIVE: To observe the content of leptin in the abdominal subcutaneous tissues of the higher temperature zone along the Gallbladder (GB) Meridian in cholecystitis rabbits so as to explore the correlation between the temperature response and the leptin level. METHODS: Twenty-five rabbits were randomized into normal control group (n = 10) and cholecystitis model group (n = 15). Cholecystitis model was established by injection of Escherichia coli solution (0.1 mL) into the gallbladder via common bile duct after surgery. Three, 7 and 11 days following modeling, the abdominal surface thermographic images along the GB Meridian were collected by the AGA-782-type infrared imaging system (AGA's capacity). And then the subcutaneous tissues of the high temperature reaction region and the contralateral corresponding tissues of different groups were collected for assaying the leptin contents in the supernatant by radioimmunoassay after processing (homogenization and centrifugation) and for observing the morphological structure under light microscopy after sectioning and staining (toluidine blue). RESULTS: Thermographic images showed that about 70% of the animals in the model group, various lengths of high temperature reaction (0.5-1.4 degrees C) zones or bands in the abdominal region along the bilateral GB Meridian were seen, in comparison with the control group. The leptin levels in the ipsilateral (affected side) and contralateral (healthy side) tissues of the abdominal high temperature reaction zones along the GB Meridian were significantly higher in the model group than in the control group (P < 0.01), suggesting a close correlation between the leptin content change and the high temperature reaction. In addition, most fat cells were crowded to distribute closely along the blood vessels in the subcutaneous tissues of the higher temperature reaction zone in the model group, but those of the control group distribute more loosely along the blood vessels. CONCLUSION: The leptin content in the abdominal sub- cutaneous tissues of high temperature reaction zone along the GB Meridian is higher in cholecystitis rabbits, suggests a relevance of the endocrine function of fat cells to the high temperature reaction along the GB Meridian.

[Correlation between the therapeutic efficacy of electroacupuncture of ear-body acupoints and mast cells in experimental gastric ulcer rats].

OBJECTIVE: To study the interrelation between the therapeutic efficacy of electroacupuncture (EA) and mast cells (MC) in experimental gastric ulcer rats. METHODS: Thirty Wistar rats were randomly divided into normal control group, model group and EA group, with 10 cases in each. Experimental gastric ulcer model was established by injecting 20% glacial acetic acid (0.05 ml) into the tissue between the muscular layer and the placenta percreta of the gastric anterior wall in the gastric antrum under anesthesia. EA (2/15 Hz, 1 mA) was applied to bilateral "Wei" (Stomach, an otopoint) and "Zusanli" (ST 36) for 30 min, once daily for 7 days. The tissues of these two acupoints were sampled to be stained with acetylcholine esterase (AChE) and toluidine blue (TB) respectively (counterstaining) after section (15 microm). The gastric ulcer tissue was stained with H&E method RESULTS: Compared with control group, the number and degranulation ratios of MC in the dermis of "Wei"-point and ST36 region in model group and EA group increased significantly (P<0.01); while in comparison with model group, both the number and the degranulation ratio of MC in EA group decreased considerably (P<0.01). H&E stained tissues showed smooth gastric mucosal membrane in control group, ulcerative injury involving the muscular layer in model group, and mild injury in EA group. CONCLUSION: EA can suppress the degranulation of MC in "Wei"-point and ST36 regions and effectively relieve ulcerative injury in gastric ulcer rats. There exists a certain degree of interrelation among the degranulation ratio of MC, gastric ulcerative injury, and the therapeutic efficacy.

[Influence of Qingpeng plaster on blood vessels and mast cells in skin tissue of channel points of nude mice].

OBJECTIVE: To investigate the changes in the numbers of blood vessels and mast cells, which is relative to blood microcirculation in skin, during Qingpeng plaster (ZANG medicine) being applied to the skin surface of nude mice. METHOD: Fifteen healthy adult nude mice were divided into Qingpeng plaster group and the control group. The sites of skin tissues stuck with the plaster or with control plaster were selected after 7 days treated, and then all the slices stained and observed. RESULT: The numbers of the vessels and the mast cells increased in the dermal tissue of Qingpeng paster group. Although there were a few dilated blood vessels in the control group, but the numbers of the vessels and the mast cells were obviously less than those of the Qingpeng plaster group. Statistical analysis showed that there was a significant difference (P < 0.001) between tow groups. CONCLUSION: Qingpeng plaster can cause obvious vascular dilatation and promot mast cells aggregation in the Qingpeng plaster stuck parts of the skin tissue.

[Effect of electroacupuncture and moxibustion of "Dazhui" (GV14) on the number and distribution of degranulated mast cells in GV14 region].

OBJECTIVE: To compare the effects of electroacupuncture (EA) and moxibustion on the degranulated mast cell number and distribution in "Dazhui" (GV14) region of rats. METHODS: Fifteen Wistar rats were randomly divided into normal control, EA and moxibustion groups, with 5 cases in each group. "Dazhui" (GV14) was stimulated by EA (3/10 Hz, 2-4 V, 20 mm) or moxibustion (2 cones, 20 mm), thereafter, the tissues of GV14 region were sampled, quickly frozen, sectioned (20 microm) and stained with toluidine blue separately for observing the degranulated state of mast cells under microscope. RESULTS: The mast cells (MCs) distributed widely in GV14 region from the dermis, subcutaneous tissue to muscle layer. Compared with control group, MCs of moxibustion group were significantly fewer in the number (P<0.05), and those degranulated MCs in both EA and moxibustion groups were evidently more in the number (P<0.01), and the number and percentage of the degranulated MCs in moxibustion group were significantly more than those of EA group (P<0.05), suggesting that EA and moxibustion could promote the release of granules of mast cells in the stimulated acupoint region, and the effect of moxibustion is stronger. CONCLUSION: Both EA and moxibustion can promote the degranulation of MCs, and the effect of moxibustion is markedly stronger in potentiating the release of granules from MCs in GV14 in rats.

[Progress in the study on the relationship between effects of acu-moxibustion and mast cells in acupoints].

The present paper reviews develonment of researches on the relationship between mast cells (MCs) and effects of acupuncture and moxibustion from (1) the formation, distribution, types, morphological characters of MCs and their biological effects, (2) the number and degranulation of MCs in acupoints, (3) the relavance of MCs and the phenomenon of sensation transmission along meridian, and 4) the correlation between the therapeutic effect of acupuncture for relieving allergic reaction and MCs. Researches show that (1) MCs act as one of the characteristic constituents in acupoints where the MCs are in close relation with the effects of acupuncture and moxibustion, (2) MCs participate in the regulatory process of the organism in physiology and pathology. The underlying mechanism of MCs-related neuro-humoral regulation and meridian needs to be studied further.