Advances in chromatography-based methods for screening active compounds from natural products / 药学学报

Natural products have been a major source of leading compounds in drug discovery. How to effectively screen active compounds from complex matrix remains an interesting topic. In this review, we comprehensively summarized advanced liquid chromatography based approaches in natural products screening, including pre-column, on-column and post-column screening methods. Their advantages, disadvantages and prospect are also discussed.

Effect of acute intra-peritoneal infection on leptin expression levels in peripheral blood and vital organs of rats / 中国应用生理学杂志

<p><b>AIM</b>To explore the effect of acute intra-peritoneal infection on leptin expression levels in peripheral blood and vital organs, and find out the role leptin plays in acute inflammation.</p><p><b>METHODS</b>A cecal ligation and perforation model of rats was established, setting groups of sham-operation, intralipid injection, injury, estradiol injection and insulin injection. A rat leptin radioimmunoassay was used to check serum leptin concentrations at 12 h after the injury, and RT-PCR was also used to detect leptin mRNA expressions in adipose tissue, lung and liver.</p><p><b>RESULTS</b>Compared with serum leptin level of sham-operation group after injury, that of all the other four groups showed no significant difference, while the level of intralipid group was significantly higher than that of injury group and estradiol group. Compared with leptin mRNA expression level of sham-operation group after injury, that of the other four groups had different changes. Leptin mRNA expression of intralipid group was significantly increased in adipose tissue but decreased in lung and liver.</p><p><b>CONCLUSION</b>Leptin expression levels may be affected by the changes of energy metabolism and neuroendocrine function after injury, which suggests a possible protective role for leptin in the recovery of body homeostasis.</p>

Leptin decreases post-septic pulmonary and intestinal FABP levels and its mechanism / 中国应用生理学杂志

<p><b>AIM</b>To detect the effect of sepsis on fatty acid binding proteins (FABP) levels and corresponding enzymes in lung and intestine of mice, and to explore the role for FABP in acute inflammation.</p><p><b>METHODS</b>A sepsis model of mice made with cecum deligation and perforation was established, and a radioimmunoassay for FABP and 96-well spectrophotometry assays for myeloperoxidase (MPO) and superoxide dismutase (SOD) which were related with clearance of free radicals,were used to detect their levels in lung and intestine homogenized fluids. Hematoxylin-eosin stain was used simultaneously to check the histopathologic chanes of both tissues.</p><p><b>RESULTS</b>Compared with sham group (108.11 +/- 94.03 and 67.22 +/- 19.47 ng/ml) 6 h and 12 h after sepsis, FABP levels in lung and intestine were significantly higher (204.98 +/- 70.72 and 154.29 +/- 60.14 ng/ml), respectively. Twelve hours after leptin (0.1 mg/kg i p) and indomethacin (2 mg/kg i p) injection, lung FABP level decreased and was lower than septic group (P < 0.05). Moreover, 12 h after sepsis intestinal FABP increased, but it decreased after leptin injection (419.80 +/- 80.06 vs 191.09 +/- 96.75 ng/ml), while indomethacin injection had no such effect. MPO and SOD activities in lung and intestine changed accordingly with time after sepsis, the effect of leptin and indomethacin injections on it had no significant correlation with FABP changes.</p><p><b>CONCLUSION</b>Leptin can protect vital organ functions such as lung and intestine after sepsis, as FABP levels, the cellular injury marker, were significantly lower than groups without injection. And this effect might have no correlation with the clearance factors of oxygenic free radicals such as MPO and SOD.</p>

Interleukin-1beta expression and phospholipase A(2) activation after intestinal ischemia/reperfusion injury / 生理学报

The experiments were carried out to explore the interactions between IL-1 beta gene expression, protein level and phospholipase A(2) PLA(2) inhibition after intestinal ischemia/reperfusion injury. Using a rat intestinal ischemia/reperfusion injury model, after collecting the serum, lung lavage, abdomen cavity lavage and important organ tissue samples from control, injury and PLA(2) inhibitor treated groups, IL-1 beta level was measured by radioimmunoassay, and the mRNA expression of IL-1 beta and type II PLA (2)was determined by RT-PCR. After 6 h of injury, the IL-1 beta level in serum was significantly higher than that in the control group; an increase in IL-1 beta was also observed in abdomen cavity lavage 1 or 3 h after injury. IL-1 beta was significantly increased in liver tissue after injury, but was not changed obviously in the lung, kidney and intestinal tissues. IL-1 beta in the lung lavage was significantly higher than that of control group. The mRNA expression of IL-1 beta in lung tissue was increased after injury, but type II PLA(2) mRNA expression was decreased. There were different changes in IL-1 beta level and gene expression after treatment with PLA(2) inhibitor chloroquine, cyclo-oxidase inhibitor indomethacin, or PAF receptor antagonist SR27417 respectively after injury. All these results indicate that after intestinal ischemia/reperfusion injury, the IL-1 beta level and mRNA gene expression are significantly increased, however, the relationship among IL-1 beta, PLA(2) activation and its metabolite release remains to be further elucidated.