Radix Pseudostellariae is used as a tonic drug in traditional Chinese medicine with immunomodulating and anti-fatigue activities, and the polysaccharide is considered as the main active component. The purpose of this study is to examine the effect of the polysaccharide isolated from Radix Pseudostellariae (PRP) on mouse chronic fatigue syndrome (CFS) induced by intraperitoneal injection of polyriboinosinic:polyribocytidylic acid (poly I:C), a double-stranded synthetic RNA. It has shown that the fatigue symptom of mice lasted at least 1 week as evaluated by forced swimming time. PRP (100, 200, 400 mg kg−1), orally administered 3 days before poly I:C injection, showed dose-dependent anti-fatigue effects. In addition, poly I:C led to evident alternations in neuroendocrine and immune systems of mice, such as reduced spontaneous activity and learning ability, declined serum level of corticosterone, increased weight indexes and T lymphocyte numbers in thymuses and spleens, and increased CD4+/CD8+ ratio but decreased proliferation ability of T lymphocytes in spleens. PRP alleviated the abnormalities caused by poly I:C, and restored the function of hosts to normal conditions. The findings suggest that PRP is beneficial to CFS, and the underlying mechanisms of action involve neuroendocrine and immune systems.

It is believed that the production and accumulation of beta-amyloid (Abeta) peptide is a critical step to the pathogenesis of Alzheimer's disease (AD). BACE 1 (beta-site APP-cleaving enzyme 1 or beta-secretase), the key enzyme required for generating Abeta from the beta-amyloid precursor protein (APP), is regarded as an ideal target for AD therapeutic drug design. Due to low oral bioavailability, metabolic instability and poor ability to penetrate the central nervous system (CNS) of the existing peptidomimetic inhibitors, researchers have paid more attention to the development of nonpeptidomimetic inhibitors in recent years. A number of drug screening approaches and technologies have been used to identify novel nonpeptidomimetic BACE 1 inhibitors. This review mainly focuses on the recent developments in structure-based design and synthesis of the nonpeptidomimetic BACE 1 inhibitors.

The present study was performed to investigate the anti-septic effects of Qi-Shao-Shuang-Gan (QSSG), a combination of Astragalus membranaceus saponins (SAM) and Paeonia lactiflora glycosides (GPL), in septic mice induced by cecal ligation and puncture. QSSG was shown to elevate the survival rate of mice, decrease infiltration of polymorphonuclear leukocytes into livers and lungs, lower serum levels of myeloperoxidase, nitric oxide, and lactate dehydrogenase, and decrease mRNA expressions of inducible nitric oxide synthase and interleukin-1β in livers. It also restored the impaired expressions of protein C (PC) mRNA in mouse livers and expressions of thrombomodulin and endothelial PC receptor mRNA in endothelial cells. Neither SAM nor GPL alone could significantly increase the survival rate of septic mice. The findings indicate that QSSG exerts protective action against polymicrobial sepsis by inhibiting systemic inflammatory response and upregulating PC pathway, and there are synergistic effects between SAM and GPL.

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