Effect of Ganoderma lucidum spore on expression of insulin-like growth factor-1, nuclear factor-kappa B, and neuronal apoptosis in the epileptic rat brain

BACKGROUND：It has been reported that Ganoderma lucidum spore powder, a very well known Chinese traditional medicine, can affect immunoregulation, free radical scavenging, and anti-hypoxia responses. OBJECTIVE： To investigate the effect of Ganoderma lucidum spore powder on expression of insulin-like growth factor-1 （IGF-1）, nuclear factor-κB （NF-κB） and neuronal apoptosis in rats with pentylenetetrazol （PTZ）-induced epilepsy. DESIGN, TIME AND SETTING： A cellular and molecular biology experiment with randomized controlled study design was performed at the Central Laboratory of Basic Medical College of Jiamusi University from June to August 2005. MATERIALS： Thirty healthy, adult, male, Wistar rats were selected and randomly divided into 3 groups （10 rats per group）： control, epilepsy model, and Ganoderma lucidum spore powder. A sub-eclampsia PTZ dose （35 mg/kg） was intraperitoneally injected to induce epilepsy in the latter two groups. Wild Ganoderma lucidum spore powder （30 g/L） was provided by the wild Ganoderma lucidum plant nursery at Jiamusi, China. Immunohistochemical detection and terminal deoxynucleotidyl transferase-mediate dUTP nick end-labeling （TUNEL） kits were purchased from Wuhan Boster Biological Technology Co., Ltd., China. METHODS： Ganoderma lucidum spore powder was intragastrically administered at a dose of 10.0 mL/kg, once a day for 28 days. In the epilepsy and control groups, an equivalent volume of normal saline was intragastrically administered. MAIN OUTCOME MEASURES： Immunoreactivity for IGF-1 and NF-κB/P65 were detected by immunohistochemical staining. Neuronal apoptosis was detected using TUNEL methods. RESULTS： The hippocampus and cerebral cortex of rats with PTZ-induced epilepsy exhibited a higher number of apoptotic cells at high magnification （×400）, compared with the control group. Expression of IGF-1 and NF-κB were higher in the epilepsy group, compared with the control group （P 〈 0.01）. In Ganoderma lucidum spore-treated rats, fewer apoptotic cells were observed in the hippocampus and cerebral cortex, expression of NF-κB/P65 was lower, and immunoreactivity to IGF-1 increased more distinctly, compared with the epilepsy group. In addition, seizure latency was longer on 17, 21, and 25 days post-PTZ treatment in the Ganoderma lucidum spore powder group, compared with the epilepsy group （P 〈 0.05-0.01）. CONCLUSION： Ganoderma lucidum spore powder down-regulated expression of NF-κB in brain tissues of rats with PTZ-induced epilepsy, increased immunoreactivity to IGF-1, and inhibited neuronal apoptosis. These results indicated that Ganoderma lucidum spore powder has a neuroprotective effect.

Hepatic Expression of Insulin-Like Growth Factor-1 inUnderfed Pregnant Ewes

The liver is one of the most important visceral organs, which represents a large contribution to whole animal energyexpenditure and the major synthetic site of insulin-like growth factor-I （IGF-1） peptide. Decreased plane of nutrition acts byreducing the metabolic rate and mass of metabolic tissues, such as liver. Also, undernutrition results in the reduced circulating IGF-1concentrations, due to the uncoupled growth hormone-IGF （GH-IGF） axis. This study investigated whether a 22-day period ofundernutrition （half maintenance） could affect liver mass and IGF-1 protein and gene expression. Sixteen pregnant ewes fed all （n =9） or half （n = 7） of their maintenance energy requirements were slaughtered on day 7 of pregnancy （oestrus = day 0）. Body and livermass, IGF-1 plasmatic concentrations and liver IGF-1 mRNA and protein expression were determined. Liver mass and the proportionof liver mass to empty body weight were lower in underfed animals. While IGF-1 plasmatic concentrations were lower inundernourished ewes, no differences in liver mRNA expression were found. This is the first time that differences inimmunohistochemistry intensity and total content are reported in sheep. In summary, the decreased plasma IGF-I concentrationsinduced by undernutrition in ewes was not associated with its reduced hepatic mRNA or protein expression, but to a decrease in livermass.

Hypoxia regulates reactive oxygen species levels in SHG-44 glioma cells

In the present study, cultured human SHG-44 glioma cells were subjected to a hypoxic environment simulated using the CoOl2 method. Flow cytometry showed increased reactive oxygen species production in these cells. Real-time reverse transcription-PCR showed significantly increased hypoxia-inducible factor-la mRNA expression in cells exposed to the hypoxic condition. The antioxidant N-acetylcysteine significantly inhibited reactive oxygen species production and reduced hypoxia-inducible factor-la mRNA expression in normoxic and hypoxic groups, especially in the latter group. These findings indicate that hypoxia induces reactive oxygen species production and hypoxia-inducible factor-la mRNA expression in human SHG-44 glioma cells, and that the antioxidant N-acetylcysteine can inhibit these changes.

Effects of IGF-1 and oxLDL on expression of phosphatase PHLPP1 in vascular smooth muscular cells

Objective To investigate the effects of insulin-like growth factor-1 （IGF-1） and oxidized low density lipoprotein （oxLDL） on expression ofphosphatase PHLPP 1 in vascular smooth muscle cells （VSMCs）. Methods Rabbit aortic VSMCs were cultured. VSMCs proliferation ability was determined by measuring cell number and mitochondrial dehydrogenase （MD） activity with MTT assay. Western blot was used to detect the protein expression ofphosphatase PHLPP1. Results IGF-1 （100ug/L） increased cell number and MD activity to 3.02 and 3.59 times of that in control group, oxLDL（501xg/ml） elevated the above two parameters to 2.03 and 2.91 times respectively. Western blot showed that IGF-1 and oxLDL inhibited the expression of PHLPPI to 39.27% and 40.26% of the control group （P〈0.01 ）. Conclusion IGF- 1 and oxLDL may enhance the proliferation of VSMCs by decreasing the expression ofphosphatase PHLPP 1.

Correlations of hypoxia-inducible factor-1α/hypoxia-inducible factor -2α expression with angiogenesis factors expression and prognosis in non-small cell lung cancer

Background Hypoxia-inducible factor （HIF） may play an important role in the process of tumorigenesis as well as tumor progression. The aim of this study was to compare the expression between HIF-1α and HIF-2α in tumor angiogenesis and the overall impact on patient prognosis in human non-small cell lung cancer （NSCLC）. Methods In the current work we compared the immunohistochemical expression of HIF-1α and HIF-21 in surgical specimens of 140 patients with NSCLC in a tissue microarray study. Relationships between HIF-α expression and clinicopathological or angiogenic factors, including prognosis, were analyzed. Results High HIF-1α and HIF-2α expression was noted in 49/140 （35.0%） and in 64/140 （45.7%） of the cases, respectively. There was no direct correlation between HIF-la and HIF-2α expression. Patients with advanced stage tumors had frequent high expression of HIF-2a （P=0.007）, and we also found a significant correlation between HIF-2α and T or N stage （P=0.030 and 0.043, respectively）. HIF-1α showed a marginal association with T stage （P=0.084）, which showed a higher expression in early stage tumors. A significant correlation （p=0.045） was noticed between HIF-1α and vascular endothelial growth factor （VEGF） expression while the expression levels of thymidine phosphorylase （TP）, cyclooxygenase （COX）-2 and microvessel density （MVD） were significantly higher in high HIF-2a tumors （P=0.020, 0.004 and 0.046, respectively）. In addition, univariate analysis of overall survival demonstrated that HIF-2a expression, but not HIF-la, was related to poor outcome （P=-0.001） and it retained significant in multivariate analysis （P=0.036）. Conclusions Taken together, we conclude that HIF-1α and HIF-2α may differentially regulate the major angiogenic factors in different stages of the tumor process in NSCLC. HIF-2α may play a dominant role in tumor angiogenesis and appears to be of obvious value as a significant prognostic factor in NSCLC.