RÉSUMÉ
Objective To investigate the correlation between brain injury and spleen damage in a rat model of acute ischemic stroke and stasis interaction,and its effect on the MCP-1/CCR2 axis,and to provide an experimental basis for the mechanism of brain-spleen inflammatory coupling in spleen lesions caused by acute ischemic stroke.Methods Forty male SD rats were randomly divided into a sham group,carrageenan/yeast stasis syndrome group(carrageenan/yeast,CA/Y),middle cerebral artery occlusion group(MCAO),and middle cerebral artery stasis syndrome group(MCAO CA/Y)with 10 rats in each group.CA/Y and MCAO CA/Y groups were injected with 10 mg/kg carrageenan and 10 mg/kg intraperitoneally on the first day of modeling.2 mg/kg of dry yeast suspension were injected subcutaneously on the second day.MCAO and MCAO CA/Y groups were established by wire embolism on the second day.At 24 h after cerebral infarction modeling,the neurological deficit score was calculated in each group,the percentage of the cerebral infarction area was determined by TTC staining,the spleen weight was measured,and the correlation between the percentage of the cerebral infarction area and spleen weight was analyzed by the Spearman correlation coefficient.Furthermore,the pathological morphology of brain and spleen tissues was observed by hematoxylin-eosin(HE)staining,and chemotactic protein 1(MCP-1)and interferon-γ(IFN-γ)contents were measured in rat plasma by enzyme-linked immunosorbent assays.Western blot was used to detect chemokine C-C-motif receptor 2(CCR2)protein expression in the ischemic side of brain tissue.Results Compared with the sham group,the neurological deficit score,cerebral infarction area,and MCP-1 and IFN-γ contents in plasma were significantly increased(P<0.01),spleen weight was decreased significantly(P<0.01),and CCR2 protein expression in brain tissue was significantly upregulated(P<0.05)in MCAO and MCAO CA/Y groups.Moreover,the area of cerebral infarction was increased significantly(P<0.01),the spleen weight was decreased significantly(P<0.01),and CCR2 protein expression in brain and spleen tissues was significantly upregulated(P<0.05)Compared with the MCAO group,the area of cerebral infarction in the MCAO CA/Y group was significantly increased(P<0.01)and the spleen weight was decreased significantly(P<0.05).Spearman correlation analysis showed that the spleen weight was negatively correlated to the percentage of the cerebral infarction area(P<0.01,r=-0.9711).Pathological morphology observation revealed that the pathological changes in the MCAO CA/Y group were the most serious,cerebral liquefaction necrosis foci were seen in the brain tissue cortex,arrangement of neuronal cells in the lesions was sparse and disordered with volume atrophy and a small number of vacuoles and nuclear solidification,most neuronal cells were degenerated and necrotic,microglia hyperplasia was obvious,small blood vessels were significantly increased,and interstitial lipid degeneration was severe.The density of periarterial lymph sheath cells in some of the spleen tissue was reduced and the marginal area is widened.Conclusions A correlation between brain and spleen injury was found after acute ischemic stroke with stasis and toxin syndrome,and the chemokine signaling axis of MCP-1/CCR2 might be involved in the mechanism of brain-spleen inflammation coupling.
RÉSUMÉ
ObjectiveTo observe and compare the electrocardiogram index, myocardial morphology, and connexin 43 (Cx43) expression of two rat models of acute cerebral infarction (ACI) due to stasis combined with toxin complicated with cerebral-cardiac syndrome (CCS), and to provide experimental evidence for the research on the occurrence mechanism of cardiac diseases induced by ACI and the clinical diagnosis and treatment of CCS. MethodSixty SPF-grade male SD rats were randomized into six groups (n=10): normal , syndrome of stasis combined with toxin induced by carrageenin combined with dry yeast (CA/Y), multi-infarct induced by micro-embolism (ME), middle cerebral artery occlusion (MCAO), CA/Y+ME, and CA/Y+MCAO groups. The model of syndrome of stasis combined with toxin was established by intraperitoneal injection with carrageenan (CA) at 10 mg·kg-1 on the first day and subcutaneous injection with dry yeast (Y) suspension (2 mg·kg-1) on the second day of modeling. Twenty-four hours after the modeling of ACI, the electrocardiograms (ECGs) of rats in each group were collected and the number/percentage (%) of abnormal ECG was calculated. The infarct area of the brain was evaluated by 2,3,5-triphenyltetrazolium chloride (TTC) staining, and myocardial injury was assessed by hematoxylin-eosin (HE) staining. Immumohistochemical staining and Western blot were employed to determine the expression of Cx43 in the myocardium. ResultA certain number of rats in each model group presented abnormal ECG. Compared with the normal group and CA/Y group, CA/Y+MCAO group had the highest rate of abnormal ECG (P<0.01). Compared with the normal, CA/Y, ME, and CA/Y+ME groups, the CA/Y+ME and CA/Y+MCAO groups showed decreased amplitudes of P-wave and T-wave, shortened P-R interval, and extended Q-T interval, which were particularly obvious in the CA/Y+MCAO group (P<0.05, P<0.01) and in accordance with the cerebral infarction area and pathological changes. The expression of Cx43 was up-regulated in both CA/Y+ME and CA/Y+MCAO groups, especially in the CA/Y+MCAO group (P<0.01). ConclusionThe two rat models of ACI due to stasis combined with toxin complicated with CCS can be used to study the mechanism of heart diseases caused by cerebrovascular diseases and the therapeutic effects of Chinese medicines with the functions of resolving stasis and detoxifying. Moreover, the CA/Y+MCAO method has higher abnormal electrocardiogram rate, severer myocardial pathological injury, and higher expression of Cx43 protein. The models can be chosen according to specific experimental purpose.
RÉSUMÉ
Objective To establish a HPLC method for determination of madecassoside and asiaticoside in Centella asiatica formula granules.Methods Chromatographic separation was performed on Ultimate AQ-C18 column(4.6 mm×250 mm,5 μm) with mobile phase of acetonitrile(A)-2 mmol/L β-cyclodextrin(0~30 min:21% A→23% A;30~60 min:23% A→25% A).The flow rate was set at 1.0 ml/min, the column temperature at 30 ℃ and detection wavelength at 205 nm.Results Madecassoside and asiaticoside showed good linearity (r>0.9995) in the ranges of 0.187 7~3.754 μg and 0.184 3~3.686 μg respectively.The specificity, repeatability, precision,recovery and stability were satisfied to the method validation requirements of China Pharmacopoeia.Conclusion The method can determine madecassoside and asiaticoside in Centella asiatica formula granules.