Pennogenyl saponins induce cell cycle arrest and apoptosis in human hepatocellular carcinoma HepG2 cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Pennogenyl saponins, the characterized components of Rhizoma Paridis, have been reported to have anticancer activity through induction of apoptosis or anti-metastasis in cultured cells or animal models. The aim of the study was to evaluate the anticancer properties of four pennogenyl saponins (PS1-PS4) on a panel of human cancer and normal cell lines, and explore the potential mechanisms underlying the selective anticancer effects of the steroidal saponins in cancer cells. MATERIALS AND METHODS: Differences in the anticancer activity of pennogenyl saponins were examined by MTT assay in human cancer cell lines (HepG2 hepatocellular carcinoma cells, UACC-257 melanoma cells, MCF-7 breast and PC-3 prostate cancer cells) and normal human cell lines (L-02 liver cells and HEK293 kidney cells). Flow cytometry analysis, JC-1 staining and western blot analysis were applied to detect the effects of anticancer pennogenyl saponins on apoptosis, cell cycle, and expression and/or activation of main effectors involved in the potential signaling pathways. RESULTS: Among the tested four saponins, only PS1 and PS2 selectively inhibited cell growth in HepG2, MCF-7 and PC-3 cells. Moreover, PS1 and PS2 could significantly induce apoptosis and cell cycle G2/M arrest in HepG2 cells, which were at least associated with activation of mitochondrial caspase-dependent and -independent apoptotic cascades, inhibition of cyclin-dependent kinase 1 and PI3K/Akt signaling pathway, and modulation of mitogen-activated protein kinases. CONCLUSIONS: PS1 and PS2 had potent and selective anticancer activity to breast, liver and prostate cancer cells. Furthermore, the anticancer effects of PS1 and PS2 were associated with induction of apoptosis and blockage of cell cycle progression through multiple targets in HepG2 cells. These findings suggest that PS1 and PS2 can be considered as potential agents for the treatment of some cancers such as hepatoma.

Growth inhibition by pennogenyl saponins from Rhizoma paridis on hepatoma xenografts in nude mice.

Rhizoma paridis is widely used in the traditional Chinese medicine for the treatment of cancers. Steroidal saponins, including diosgenyl saponins and the characterized component pennogenyl saponins, are regarded as the main active components of R. paridis. To date, quite a bit of research has been published which attempt to explore the in vivo anticancer effects and the underlying mechanisms of pennogenyl saponins, compounds which are present at quite low levels in the plant. In the present study, two known pennogenyl saponins (PS1 and PS2) were isolated from R. paridis axialis and identified by spectral techniques. The anti-cancer activity of these two pennogenyl saponins was investigated in nude mice bearing human hepatocellular carcinoma (HCC) HepG2 xenografts. PS1 or PS2 (purity >98%, 1 or 3mg/kg) was administered by intraperitoneal injection, respectively. The specimens of HepG2 xenografts were removed for mechanistic study. The current results indicated that both PS1 and PS2 dose-dependently prevented the growth of HepG2 xenografts. Western blotting analysis showed that the anticancer effects of these two monomers were associated with apoptosis induction and proliferation inhibition through activation of both caspase-dependent and caspase-independent apoptotic pathways, regulation of mitogen-related protein kinase pathway and inhibition of PI3K/Akt pathway. The present data suggest, for the first time, that PS1 and PS2 effectively inhibit human HCC progression through regulation of the signal pathways associated with apoptosis and proliferation, and have the potential for the treatment of HCC.

Klotho upregulation contributes to the neuroprotection of ligustilide in an Alzheimer's disease mouse model.

Klotho, an aging-suppressor gene, encodes a protein that potentially acts as a neuroprotective factor by modulating insulin-like growth factor 1 signaling and oxidative stress. In the present study, we investigated the potential role of Klotho in the therapeutic effect of ligustilide against Alzheimer's disease (AD)-like neuropathologies and memory impairment in aged senescence-accelerated mouse prone-8 (SAMP8) mice. Ligustilide treatment (10 and 40 mg/kg for 8 weeks, intragastrically) in 10-month-old SAMP8 mice reduced memory deficits, amyloid-ß(1)-42 accumulation, tau phosphorylation, and neuron loss, increased mitochondrial manganese-superoxide dismutase and catalase expression and activity, and decreased malondialdehyde, protein carbonyl, and 8-hydroxydesoxyguanosine levels in the brain. Ligustilide upregulated Klotho expression in the cerebral choroid plexus and serum, decreased Akt and Forkhead box class O1 phosphorylation. Moreover, ligustilide inhibited the insulin-like growth factor 1 pathway and induced Forkhead box class O1 activation in 293T cells along with Klotho upregulation. An inverse correlation was found between Klotho expression and the AD phenotype, suggesting that Klotho might be a novel therapeutic target for age-related AD, and Klotho upregulation might contribute to the neuroprotective effect of ligustilide against AD.

Aqueous extract of Gleditsia sinensis Lam. fruits improves serum and liver lipid profiles and attenuates atherosclerosis in rabbits fed a high-fat diet.

ETHNOPHARMACOLOGICAL RELEVANCE: Gleditsia sinensis Lam. has been used in the traditional Chinese medicine as a chief ingredient of many polyherbal formulations for the treatment of obesity and thrombosis. AIM OF THE STUDY: To evaluate the effects of Gleditsia sinensis Lam. fruit aqueous extract (GAE) on hyperlipidemia and atherosclerosis in Japanese white rabbits on a high fat diet. MATERIALS AND METHODS: Rabbits were divided into four groups: the normal control with a normal diet, and high-fat diet-fed model group and GAE-treated groups supplemented with GAE (6 or 12 mg/kg/day, p.o.), respectively. The groups fed high-fat diets were given i.v. with bovine serum albumin (BSA) on the 4th week to induce atherosclerosis. The serum lipid profile, including triglycerides (TG), total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C), was determined on the 0th, 4th, 8th and 14th week, respectively. And the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and creatine kinase (CK) were measured simultaneously. At the end of the experiment, the rabbits were sacrificed, and the atherosclerotic plaques as well as the histopathological changes of aorta and liver were assessed by oil-red or HE staining, respectively, and the aorta and liver lipid profiles were also assayed. RESULTS: Results showed that the prophylactic treatment with GAE could significantly decrease the lipid levels of serum, aorta and liver, attenuate aortic atherosclerosis and improve aortic remodeling without the significant liver and muscle toxicity. CONCLUSION: The present findings suggest that GAE can effectively attenuate the atherosclerotic at least through anti-hyperlipidemic activity and thus has the therapeutic potential in treating hyperlipidemia-related cardiovascular diseases.

Z-ligustilide extracted from Radix Angelica Sinensis decreased platelet aggregation induced by ADP ex vivo and arterio-venous shunt thrombosis in vivo in rats.

Antithrombotic therapy has become an important goal for the treatment of ischemic disorders such as cerebral ischemia. Our recent studies found that Z-ligustilide (LIG), a characterized 3-n-alkylphthalide constituent of Radix Angelica sinensis essential oil, exerted significant neuroprotection against cerebral ischemic damage in several animal models. The present study evaluated the antithrombotic activity of LIG and its effect on platelet aggregation and coagulation time. LIG (10 or 40 mg/kg) was intragastrically administered to rats once daily for 3 days. Our results showed that LIG significantly and dose-dependently reduced arterial thrombus weight in an arteriovenous shunt thrombosis in rats and platelet aggregation induced by adenosine diphosphate in rats ex vivo. Meanwhile, LIG at 10 or 40 mg/kg had no significant effect on coagulation time, including activated partial thromboplastin time and prothrombin time, in rats ex vivo. The present study demonstrated for the first time that LIG may exert efficient antithrombotic activity through inhibition of platelet aggregation, without effecting coagulation time of peripheral blood. These data, together with the previously reported neuroprotective effects of LIG on cerebral ischemia, suggest that the antithrombotic activity of LIG may contribute to its potential for the treatment of ischemic diseases, including ischemic stroke.

Protective effect of Z-ligustilide against amyloid beta-induced neurotoxicity is associated with decreased pro-inflammatory markers in rat brains.

Neuroinflammatory responses induced by accumulation and aggregation of beta-amyloid (Abeta) peptide are mainly involved in Alzheimer's disease (AD) pathogenesis. Z-ligustilide (LIG), a novel neuroprotectant against ischemic stroke, was reported to have significant anti-inflammatory effects via inhibition of TNF-alpha production and bioactivity. The present study investigated the effect of LIG on AD-like cognitive impairment and neuropathological and neuroinflammatory changes induced by bilateral intracerebroventricular injections of Abeta(25-35) at a dose of 50 nmol/rat. Rats received oral administration of 40 mg/kg LIG or volume-matched vehicle 1 h before Abeta(25-35) treatment then once daily for 15 days. Morris water maze was used to detect the cognitive dysfunction induced by Abeta(25-35). Compared to the sham-operated rats, Abeta(25-35) injection significantly prolonged the mean escape latency in vehicle-treated rats in the Morris water maze test (p < 0.01) and increased both AD-related neuropathological signs (i.e., Abeta, amyloid precursor protein, and phosphorylated Tau immunoreactivity) and pro-inflammatory mediators (i.e., TNF-alpha and activated NF-kappaB) in the prefrontal cortex and CA1 subregion of the hippocampus. And these neurotoxic effects of Abeta(25-35) were significantly ameliorated with LIG treatment (p < 0.01 vs. vehicle-treated group). The present data suggest that LIG modulates TNF-alpha-activated NF-kappaB signaling pathway with respect to its protective effect against Abeta(25-35)-induced neurotoxicity. LIG would be a potential candidate for further preclinical study aimed at the prevention and treatment of cognitive deficits in AD.