Expression of c-Fos protein and nitricoxide synthase in neurons of cerebral cortex from fetal rats in hypoxia and protective role of Angelica sinensis

BACKGROUND： Both c-Fos protein and nitricoxide synthase （NOS） have been used as general indexes in relative research about neurons, but it is lack of reports that c-Fos protein and NOS are applied synchronously to study the neurons of hypoxic fetal rats in uterus. OBJECTIVE： To study the effect of hypoxia in uterus on the expression of c-Fos protein and NOS in neurons of cerebral cortex from fetal rats and whether Angelica sinensis has the protective effect on these neurons in hypoxia. DESIGN： Randomized control experiment.SETTING ： Department of Histology and Embryology, Luzhou Medical College.MATERIALS ： Twelve adult female Wistar rats in oestrum and 1 male Wistar rat with bodymass from 220 to 250 g were chosen. Parenteral solution of Angelica sinensis mainly contained angelica sinensis, 10 mL/ampoule, was provided by Department of Agent of the Second Hospital Affiliated to Hubei Medical University （batch number： 01062310）. METHODS ： This experiment was completed in the Department of Histology and Embryology of Luzhou Medical College from September 2003 to June 2004. ①Twelve adult female Wistar rats in oestrum and 1 male Wistar rat were housed in one rearing cage. Vaginal embolus was performed on conceive female rat at 8： 00 am next day. On the 15^th conceiving day, all conceiving rats were divided randomly into three groups： control group, hypoxia group and Angelica group with 4 in each group. Rats in hypoxia group and Angelica group were modeled with hypotonic hypoxia in uterus. Angelica group： Rats were injected with 8 mL/kg Angelica sinensis injection through caudal veins before hypoxia. Hypoxia group： Rats were injected with the same volume of saline. Control group： Rats were not modeled and fed with normal way. ② Twenty embryos of rats were chosen randomly from each group and then routinely embedded in paraffin. Paraffin sections were cut from the brain of embryos to anterior fontanelle. Double-label staining was used to detect the expression of nNOS and c-Fos in neurons of cerebral cortex from embryos of rats. OLYMPUS Bx-50 microscope was used to observe sections and DP12 digit camera was also used under 400 times to detect types of cells. Under microscope, the number of c-Fos, NOS, c-Fos/NOS positive neurons in cerebral cortex from embryos of rats were counted in 2 fields with magnification of 400 in one section per animal. ③ The data in experiments were analyzed by one-way analysis of variance （ANOVA） followed by q test. MAIN OUTCOME MEASURES： ① Results of immunohistochemical double-label staining of c-Fos/NOS from cerebral cortex; ② Comparison of amount immunohistochemical double-label staining of c-Fos/NOS positive cells from cerebral cortex. RESULTS：① The positive NOS cells and c-Fos/NOS cells in the three groups were mainly distributed in cerebral cortex, but positive c-Fos neurons were not observed. ② Positive NOS cells and c-Fos/NOS cells in hypoxia group were more than those in control group （76.55±12.02, 50.45±10.39; 33.35±7.42, 26.35±6.67, P 〈 0.05）, but those in Angelica group were less than those in hypoxia group （51.70±9.82, 35.65±8.37, P 〈 0.05）. CONCLUSION： Hypoxia can stimulate the increase of expression of c-Fos protein and NOS in neurons of cerebral cortex. However, Angelica sinensis can decrease this expression so as to play a protective role in cerebral neurons of hypoxic fetal rats.

Inhibition of epidermal growth factor receptor signaling protects human malignant glioma cells from hypoxia - induced cell death

Epidermal growth factor receptor(EGFR)signaling has become an importanttarget for drug development becauseEGFR signaling enhances tumor cell proliferation,migration,and invasion and inhibits apoptosis.However,theresults of clinical trials using EGFR inhibitors in patients with solid tumors have been disappointing.Here,wereport a protective effect of the EGFR inhibitors AG1478 and PD153035 against cell death induced by acute hy-poxia,which contrasts with their proapoptotic effects under normoxia.Under hypoxic conditions,both agents re-

New C_(21)steroidal glycosides from the roots of Cynanchum stauntonii and their protective effects on hypoxia/reoxygenation induced cardiomyocyte injury

Phytochemical investigations from the roots of Cynanchum stauntonii led to obtain four new C_（21） steroidal glycosides（1–4） and one known compound stauntoside F（5）. Their chemical structures were characterized by sophisticated analyses of IR, HRESI-TOF-MS, 1D, and 2D-NMR data, together with chemical methods, which showed interesting 13,14：14,15-disecopregnane-type skeleton or 14,15-secopregnane-type skeleton C_（21） steroidal glycosides. Among them, compound 1 was determined to be glaucogenin C 3-O-b-D-glucopyranosyl-（1 → 4）-b-D-cymaropyranosyl-（1 → 4）-b-D-digitoxopyranosyl-（1 → 4）-b-D-thevetopyranoside. Compound 2 was characterized to be hirundigenin 3-O-a-L-diginopyranosyl-（1 → 4）-b-D-cymaropyranosyl-（1 → 4）-b-D-digitoxopyranosyl-（1 → 4）-b-D-30-demethyl-thevetopyranoside. Compound 3 was identified to be（14S,16 S,20R）-14,16-14,20-15,20-triepoxy-14,15-secopregn-5-en-3-ol-3-O-a-L-cymaropyranosyl-（1 → 4）-b-D-digitoxopyranosyl-（1 → 4）-b-D-oleandropyranoside.Compound 4 was identified to be（14S,16 S,20R）-14,16-14,20-15,20-triepoxy-14,15-secopregn-5-en-3-ol-3-O-a-L-cymaropyranosyl-（1 → 4）-b-D-cymaropyranosyl-（1 → 4）-b-D-digitoxopyranosyl-（1 → 4）-b-Dthevetopyranoside. Among them, compound 2 was hirundigenin type C21 steroidal glycoside that existed in nature as epimers due to the presence of 14-hemiketal hydroxyl group in its structure. In addition, the anti-inflammatory and cardiomyocyte protective effects of compounds 1–4 were evaluated. We found that they exhibited significant protective effects on hypoxia/reoxygenation induced cardiomyocyte injury, but did not showed obvious anti-inflammatory function.

7,8-dihydroxyflavone protects human renal proximal tubular cells from hypoxia injury via inhibiting endoplasmic reticulum stress

Objective To observe the effects of 7,8-dihydroxyflavone(7,8-DHF)on hypoxia induced endoplasmic reticulum stress(ERS)in human proximal tubular epithelial cells(HK-2).Methods The mRNA level of ERS associated biomarkers was evaluated by RT-PCR assay