Characterization of pumpkin polysaccharides and protective effects on streptozotocin-damaged islet cells / 中国天然药物

The polysaccharides from pumpkin fruit (PP) were obtained and purified by hot-water extraction, anion-exchange chromatography, and gel column chromatography. The physicochemical properties of PP were determined by gel filtration chromatography, gas chromatography, fourier transform infrared (FTIR) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. Results indicated that the molecular weight of PP was about 23 kDa and PP was composed of D-Arabinose, D-Mannose, D-Glucose, and D-Galactose with a molar ratio of 1 : 7.79 : 70.32 : 7.05. FTIR and NMR spectra indicated that PP was the polysaccharide containing pyranose ring. Additionally, PP protected islets cells from streptozotocin (STZ) injury in vitro via increasing the levels of super-oxide dismutase (SOD) and malondialdehyde (MDA) and reducing the production of NO. The experiment of reverse transcriptase-polymerase chain reaction further proved that PP inhibited apoptosis via modulating the expression of Bax/Bcl-2 in STZ-damaged islet cells. In conclusion, PP could be explored as a novel agent for the treatment of diabetes mellitus.

Effect of Ganoderma lucidum polysaccharides on oxidative stress of hyperlipidemic fatty liver in rats / 中国中药杂志

<p><b>OBJECTIVE</b>To study the effect of Ganoderma lucidum polysaccharides on oxidative stress of hyperlipidemic fatty liver in rats.</p><p><b>METHOD</b>Seventy-two SD rats were randomly divided into six groups, namely the normal control group (NG), the model group (MG), the G. lucidum polysaccharides groups of low, middle and high dose (GLPs-LG, GLPs-MG, GLPs-HG) and the Simvastatin group (SV). The rats were fed with high fat diet to establish the model of hyperlipidemic fatty liver in rats. After administration for 12 weeks, rats in each group were tested with the following indexes: total cholesterol (TC), triglyceride (TG), high density lipoprotein-cholesterol (HDL-C) and low density lipoprotein-cholesterol (LDL-C), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) in serum as well as the contents of SOD, MDA, GSH-Px and T-AOC in hepatic tissues. Histopathological changes of hepatic tissues were observed under light glass.</p><p><b>RESULTS</b>The contents of TC, TG and LDL-C were significantly increased in the model group (P < 0.01). Compared with the model group, both the GLPs-M group and the GLPs-H group showed significant decreases in TC, TG and LDL-C (P < 0.05 or P < 0.01), while the GLPs-H group showed a notable increase in HDL-C (P < 0.05). Compared with the model group, both the GLPs-M group and the GLPs-H group showed significant decreases in MDA (P < 0.05 or P < 0.01) and notable increases in SOD, GSH-Px, T-AOC (P < 0.05 or P < 0.01). The GLPs-M group and the GLPs-H group proved a remarkable alleviation in fatty degeneration of hepatic cells.</p><p><b>CONCLUSION</b>G. lucidum polysaccharides can significantly reduce the blood fat level of hyperlipidemic fatty liver in rats and effectively inhibit oxidant stress, showing the effect on preventing and treating hyperlipidemic fatty liver in rats to some extent.</p>

Identification of differentially expressed genes in dorsal root ganglion in early diabetic rats / 神经科学通报·英文版

<p><b>OBJECTIVE</b>To screen and identify differentially expressed genes in the dorsal root ganglion (DRG) in early experimental diabetic rats.</p><p><b>METHODS</b>Diabetic model rats were induced by single intraperitoneal injection of streptozotocin (STZ). At the second week after STZ injection, the sensory nerve conduction velocities (SNCV) of sciatic nerve were measured as an indicator of neuropathy. The technique of silver-staining mRNA differential display polymerase chain reaction (DD-PCR) was used to detect the levels of differentially expressed genes in rat DRG. The cDNA fragments that displayed differentially were identified by reverse-hybridization, cloned and sequenced subsequently, and then confirmed by Northern blot.</p><p><b>RESULTS</b>The SNCV in the diabetic model group [n = 9, (45.25+/-10.38) m/s] reduced obviously compared with the control group [n = 8, (60.10+/-11.92) m/s] (P < 0.05). Seven distinct cDNA clones, one was up-regulated gene and the others were down-regulated ones, were isolated by silver-staining mRNA differential display method and confirmed by Northern blot. According to the results of sequence alignment with GenBank data, majority of the clones had no significant sequence similarity to previously reported genes except only one that showed high homology to 6-pyruvoyl-tetrahydropterin synthase mRNA (accession No. BC059140), which had not been reported to relate to diabetic neuropathy.</p><p><b>CONCLUSION</b>These differentially expressed genes in the diabetic DRG may contribute to the pathogenesis of diabetic peripheral neuropathy.</p>

Benazepril and Candesartan Attenuate Oxidative Stress in Aorta in Spontaneously Hypertensive Rats / 中华高血压杂志

Objective To study the anti-oxidative stress effects of benazepril and candesartan.Methods SHRs of 12 weeks old were given benazepril(10 mg/kg?d,n=9)or candesartan(4 mg/kg?d,n=9)or combina- tion(Ben:10 mg/kg?d+Can:4 mg/kg?d)for 12 weeks.The tail arterial pressure was measured every two weeks.At end of study,pathological changes in the thoracic aorta,activity of SOD,serum contents of NO and hydroxy radicals,plasma Ang Ⅱ and cGMP,eNOS and P22~(phox)protein expressions in aortic tunica intima were de- termined.Results The thoracic aorta wall was thickened markedly in SHRs,and blood pressure,hydroxy radi- cal,Ang Ⅱ and P22~(phox)protein expression were increased significantly,while the serum NO,level of cGMP and eNOS expression were decreased.Benazepril(Ben)or Candesartan(Can)inhibit the thickening of vessel wall, enhance the activity of SOD(Ben:68.7?2.1,Can:65.6?4.2 vs SHR:48.8?3.2 U/mL,P