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Objective To study the effect of glycyrrhizin(GL) on the gene expression of high mobility group protein 1 (HMGB1) in hippocampus and serum.To evaluate the effect on the expression of neuron-specific nuclear-binding protein (Neu-N) in the hippocampus CA1,CA3 regions in the chronic stage of an immature rat epilepsy model.Methods Fifty-two 21 day-old SD rats were randomly divided into control group,model group Ⅰ and model group Ⅱ according to the random table method.Model group Ⅰ was induced epilepsy by kainic acid (KA),and the model group Ⅱ was pretreated with GL by intraperitoneal injection at 30 min before KA injection.According to the different observation time points,each group was divided into 4 subgroups:3 h,12 h,24 h and 7 d.Model group Ⅱ was divided into 3 subgroups:10 mg/kg,50 mg/kg,100 mg/kg,according to the different doses of GL.There were 3 animals in each subgroup.Score was performed according to the Racine score,and quantitative real-time polymerase chain reaction and Western blot were applied to detect the mRNA and protein expression of HMGB1 in the acute phase.Enzyme-linked immunosorbent assay(ELISA) was applied to measure the expression of HMGB1 in blood;immunohistochemical was applied to measure the expression of Neu-N in hippocampus in the chronic phase(7 d).Results Compared with model group Ⅰ,seizure onset time was obviously prolonged in model group Ⅱ [(24.08 ± 1.98) min vs.(33.39 ± 2.66) min],and the difference was statistically significant (t =9.231,P ＜0.05);Comparing KA model group Ⅰ with control group,the gene expression of HMGB1 significantly increased,and reached a peak at the time of 12 h (H =10.532,P ＜ 0.05),but the protein expression of HMGB1 was changed obviously and there was no significant difference (H =5.227,P ＞0.05).The expression of HMGB1 in the serum also significantly increased,especially at 12 h (H =6.897,P ＜0.05).At the time of 12 h after KA injection,the gene expression of HMGB1 in the hippocampus was significantly decreased in model group Ⅱ compared with model group Ⅰ (H =10.721,P ＜0.05) (especially in the 100 mg/kg model group).Also,the expression of HMGB1 in the scrum was obviously decreased (H =6.967,P ＜ 0.05) (especially in the 100 mg/kg model group).At the time of 7 d after KA injection,hippocampal neuron loss in model group.Ⅰ was significantly reduced compared with control group (P ＜ 0.05),and hippocampal neuron loss in model group Ⅱ was evidently decreased compared with model group Ⅰ (P ＜ 0.05),(especially in the 100 mg/kg model group in CA1,50 mg/kg model group in CA3).Conclusions In the immature rat temporal lobe epilepsy model,GL may have neuroprotective by inhibiting the synthesis and release of HMGB1,inhibiting inflammation further to restrain the loss of neurons in the chronic phase.
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Plants of the genus Taraxacum, commonly known as dandelions, are used to treat breast cancer in traditional folk medicine. However, their use has mainly been based on empirical findings without sufficient scientific evidence. Therefore, we hypothesized that dandelions would behave as a Selective estrogen receptor modulator (SERM) and be effective as hormone replacement therapy (HRT) in the postmenopausal women. In the present study, in vitro assay systems, including cell proliferation assay, reporter gene assay, and RT-PCR to evaluate the mRNA expression of estrogen-related genes (pS2 and progesterone receptor, PR), were performed in human breast cancer cells. Dandelion ethanol extract (DEE) significantly increased cell proliferation and estrogen response element (ERE)-driven luciferase activity. DEE significantly induced the expression of estrogen related genes such as pS2 and PR, which was inhibited by tamoxifen at 1 μmol·L(-1). These results indicated that DEE could induce estrogenic activities mediated by a classical estrogen receptor pathway. In addition, immature rat uterotrophic assay was carried out to identify estrogenic activity of DEE in vivo. The lowest concentration of DEE slightly increased the uterine wet weight, but there was no significant effect with the highest concentration of DEE. The results demonstrate the potential estrogenic activities of DEE, providing scientific evidence supporting their use in traditional medicine.
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Animals , Female , Humans , Rats , Breast Neoplasms , Drug Therapy , Metabolism , Cell Proliferation , Estrogen Replacement Therapy , Methods , Gene Expression , MCF-7 Cells , Phytoestrogens , Metabolism , Phytotherapy , Plant Extracts , Pharmacology , Therapeutic Uses , Plant Leaves , Receptors, Estrogen , Metabolism , Selective Estrogen Receptor Modulators , Pharmacology , Taraxacum , UterusABSTRACT
Objective To explore the effect of postnatal infection on SOX10 expression in cerebral white matter in immature rats. Methods A total of 96 newborn SD rats were randomly divided into hypoxia group, lipopolysaccharide (LPS) group, and control group. At day 3 and 6 after birth, the rats in LPS group and hypoxia group were intraperitoneally injected with 0.25 mg/kg of LPS while the rats in control group were injected with normal saline. Meanwhile the rats in hypoxia group were maintained in a hypoxic tank under atmospheric pressure and thermostatic water bath at 37℃for 2 hours of ventilation with mixed gas con-taining 8%O2 and 92%N2 at a rate of 2 L/min starting 3 days after birth. At day 7, 10, 14, 21 after birth, eight rats in each groups were sacriifced and the cerebral white matter was extracted. HE staining was performed to observe the pathological changes of cerebral white matter by light microscopy. The expression of SOX10 in cerebral white matter was determined by immunohisto-chemical and Western blotting analysis. The expression of TLR-4 was determined by Western blotting. Results In LPS group and hypoxia group, the SOX10 positive cells and expressions of SOX 10 and TLR-4 were increased at day 7, reached the peak at day 10, and then gradually declined. There were signiifcant differences between any two time points (P0.05). At each time point, the difference in the SOX10 positive cells and the expressions of SOX 10 and TLR-4 were statistically signiifcant among three groups (PLPS group>control group and there were signiifcantly differences between each groups (P<0.05). Conclusions Postnatal infections can lead to cerebral white mat-ter lesions in immature rats. The existence of both hypoxia and infection can aggravate the brain injury. The high expression of SOX 10 may have the protective effect.
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Objective To evaluate whether recombinant human erythropoietin (rh-EPO) could increase the angiogenic responses in preterm rat models with periventricular white matter damage (PWMD).Methods Three-day postnatal rats were divided into 3 groups randomly:the sham group,the hypoxic-ischemic (HI) group and the recombinant human erythropoietin(rh-EPO)treatment group.Rat pups underwent permanent ligation of the right common carotid artery followed by 60 mL/L O2 for 4 h or sham operation and normoxic exposure.Immediately after the HI,rats received a single intraperitoneal injection of rh-EPO (5 U/g)or saline.Angiogenesis-related cells (CD34 + cells),microvessel density (MVD)and arteriovenous related genes (ephrinB2 and EphB4)were examined at 48 h and 96 h after operation.Results At 48 h after operation,the proteins of CD34 in HI rats increased compared with the sham rats (HI group vs Sham group:0.54 ± 0.05 vs 0.42 ± 0.05,P ＜ 0.05).However,the MVD,the mRNA of ephrinB2 and EphB4 did not change (P ＞ 0.05).The proteins of CD34,the mRNA of ephrinB2 and EphB4 increased after rh-EPO treatment compared with HI rats.However,the MVD did not increase.As the proteins of CD34 increased further at 96 h after operation (HI group vs Sham group:0.85 ± 0.06 vs 0.62 ± 0.06,P ＜ 0.05),the MVD (3.14 ± 1.21 vs 1.50 ± 1.04),ephrinB2 (7.51 ± 1.89 vs 1.28 ± 0.24) and EphB4 (4.58 ± 0.82 vs 1.21 ± 0.22) also increased (all P ＜ 0.05).And the proteins of CD34 increased after administration of rh-EPO(EPO group vs HI group:0.98 ± 0.07 vs 0.85 ± 0.06,P ＜0.05) and MVD(EPO group vs HI group:4.71 ± 1.38 vs 3.14 ± 1.21,P ＜0.05) were increased after administration of rh-EPO.However,the ephrinB2 and EphB4 did not increased after administration of rh-EPO at 96h time point.Conclusion Endogenous regenerative response is triggered in the damaged tissues and rh-EPO increases the angiogenesis in model rats with PWMD.
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Objective To study the effect of hypoxia-ischemia (HI) on the brain-derived neurotrophic factor (BDNF) expression in the brain cortex and the hippocampus of immature rats,and to provide new therapeutic strategies for HI brain injury.Methods Three-day-old rats were divided into 2 groups.One group of rat pups were subjected to the left carotid artery ligation followed by 60 mL/L oxygen for 2.5 hours(HI-treated rats).The other group of rat pups were only subjected to the left carotid artery separation without ligation and 60 mL/L oxygen (sham-treated rats).The brain tissues were prepared at 3,7 and 14 d after treatment.Cresyl fast videt(CV) staining was used to evaluate the damage of the cortex and the hippocampus and check whether the models were successfully made.Immunostaining was used to determine the changes in BDNF positive cells in the brain cortex and the hippocampus after HI.Western blot analysis was used to evaluate the expression of BDNF protein in the brain cortex and the hippocampus after HI.Results Models were successfully made.CV staining showed that there was brain damages and area loss in the cortex and the hippocampus after HI.BDNF immunostaining showed that the number of BDNF-positive cells was significantly decreased in the cortex (t =-3.225,-2.298,all P ＜ 0.05) and the hippocampus (t =-3.751,-2.920,all P ＜ 0.05) in the damaged side of the brain compared to the contralateral side in the rats treated with HI and the sham-treated rats at 3 d after surgery,while increased at 7 d(t =3.924,2.838,all P ＜ 0.05 for cortex ; t =4.136,2.256,all P ＜0.05 for hippocampus) and 14 d (t =3.256,2.624,all P ＜ 0.05 for cortex ; t =3.051,2.719,all P ＜ 0.05 for hippocampus) after surgery.Western blot analysis showed protein expressions of BDNF:(1) Hippocampus:the protein expressions of BDNF were significantly decreased in damaged side of the brain compared to the contralateral side of rats treated with HI at 3 d(t =-3.388,P ＜ 0.05) after surgery,while increased compared to the contralateral side of rats treated with HI and the sham-treated rats at 14 d(t =4.874,4.646,all P ＜0.05) after surgery.(2)Cortex:the protein expression of BDNF was significantly decreased in damaged side of the brain compared to the contralateral side of rats treated with HI and the sham-treated rats at 3 d(t =-7.386,-3.256,all P ＜ 0.05) after surgery,compared to the sham-treated rats at 7 d(t =4.439,P ＜ 0.05) and the contralateral side of rats treated with HI and the sham-treated rats 14 d(t =24.161,3.942,all P ＜ 0.05) after surgery.Conclusions The number of BDNF-positive cells and protein expressions are decreased in the cortex and the hippocampus at the early stage of HI injury,and increased at the late stage.BDNF may play a role in the healing stage of HI brain injury.
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PURPOSE: Apoptosis is a process of active cell death which has been suggested to be part of hippocampal cell loss caused by kainic acid (KA). Immature rats showed higher susceptibility and mortality to KA but did not develop recurrent seizure, long term behavioral or neuropathologic changes. We investigated whether this was due to age-dependent resistance, and elucidated the molecular mechanics which mediate P53-induced apoptosis, identifying bax and bcl-2 as P53 protein expressions that serve as a paradigm on how the balance of bcl-2 to bax is differentially altered by apoptotic stimuli. METHODS: Sprague-Dawley rats were classified into postnatal age (P) 10, 15, 20 and 30 days and given specific doses of i.p. KA (P10; 3mg/kg, P15; 4mg/kg, P20; 8mg/kg, P30; 10mg/kg). Only rats that achieved continuous clonic seizure were selected and decapitated at 24, 48, and 72h (n=15 each age). We analysed P53, bax and bcl-2 protein expressions by immunohistochemistry as well as apoptosis by TUNEL in each group. RESULTS: KA-induced hippocampal cell death first appeared in P20. Remarkable expressions of apoptosis, P53 and bax, while bcl-2 proteins were suppressed were observed at 48 hours following KA in P20 and the most prominently affected areas were hippocampal CA1 and CA3 neurons. Similar results were obtained in P30. CONCLUSOIN: A Induction of P53, a growth regulatory gene which has been implicated in apoptosis and the changes in bcl-2 to bax ratio may be important to KA mediated excitotoxicity of specific regions during the critical period of developing rat brain.
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Animals , Rats , Apoptosis , Brain , Cell Death , Critical Period, Psychological , Genes, Regulator , Hippocampus , Immunohistochemistry , In Situ Nick-End Labeling , Kainic Acid , Mechanics , Mortality , Neurons , Rats, Sprague-Dawley , SeizuresABSTRACT
Although extracorporeal shock wave lithotripsy(ESWL) has been used to treat renal stones for several years, little is known of its effect on developing tissue. To study the long-term bio-effects of this mode of treatment on the immature animal, we used 32 Sprague-Dawley rats at 4weeks of age and divided 4 groups which consisted of 8 rats respectively. They were weighted and left nephrectomy was then performed. 10 days later, 3 groups received extracorporeal shock waves (16 kV) of 500, 1,000, 1,500 times respectively to the right kidney using Lithoring(3rd generation pendulum-ESWL), but control group didn't received shock waves. They were allowed to mature, and at 16 weeks of age they were evaluated for weight and serum creatinine. The right kidney was then harvested, weighted and stained with hematoxylin and eosin. There were no significant changes in over-all animal growth, renal growth and renal function in the post-treatment groups when compared to the control group. At comparison of histological changes, the grade of interstitial nephritis was proportional to the number of shock wave received In conclusion, shock waves delivered to immature animals do not significantly affect animal growth, renal growth and function, but it can cause significant permanent histological renal changes even at low doses and further studies are needed with an adult control group in an attempt to delineate whether the immature kidney is, indeed, more vulnerable to the shock waves.