Protective Effect of Procyanidin B2 on Acute Liver Injury Induced by Aflatoxin B 1 in Rats.

OBJECTIVE: This study aimed to explore the protective effect of procyanidin B2 (PCB2) on acute liver injury induced by aflatoxin B 1 (AFB 1) in rats. METHODS: Forty Sprague Dawley rats were randomly divided into control, AFB 1, AFB 1 + PCB2, and PCB2 groups. The latter two groups were administrated PCB2 intragastrically (30 mg/kg body weight) for 7 d, whereas the control and AFB 1 groups were given the same dose of double distilled water intragastrically. On the sixth day of treatment, the AFB 1 and AFB 1 + PCB2 groups were intraperitoneally injected with AFB 1 (2 mg/kg). The control and PCB2 groups were intraperitoneally administered the same dose of dimethyl sulfoxide (DMSO). On the eighth day, all rats were euthanized: serum and liver tissue were isolated for further examination. Hepatic histological features were assessed by hematoxylin and eosin-stained sections. Weight, organ coefficient (liver, spleen, and kidney), liver function (serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, total bilirubin, and direct bilirubin), oxidative index (catalase, glutathione, superoxide dismutase, malondialdehyde, and 8-hydroxy-2'-deoxyguanosine), inflammation factor [hepatic interleukin-6 (IL-6) mRNA expression and serum IL-6], and bcl-2/bax ratio were measured. RESULTS: AFB 1 significantly caused hepatic histopathological damage, abnormal liver function, oxidative stress, inflammation, and bcl-2/bax ratio reduction compared with DMSO-treated controls. Our results indicate that PCB2 treatment can partially reverse the adverse liver conditions induced by AFB 1. CONCLUSION: Our findings indicate that PCB2 exhibits a protective effect on acute liver injury induced by AFB 1.

The Role of 6-Gingerol on Inhibiting Amyloid ß Protein-Induced Apoptosis in PC12 Cells.

Our previous study suggests that ginger root extract can reverse behavioral dysfunction and prevent Alzheimer's disease (AD)-like symptoms induced by the amyloid-ß protein (Aß) in a rat model. 6-Gingerol is the major gingerol in ginger rhizomes, but its effect on the treatment of AD remains unclear. In this study, we aimed to determine if 6-gingerol had a protective effect on Aß1-42-induced damage and apoptotic death in rat pheochromocytoma cells (PC12 cells) and to investigate the underlying mechanisms by which 6-gingerol may exert its neuroprotective effects. Our results indicated that pre-treatment with 6-gingerol significantly increased cell viability and reduced cell apoptosis in Aß1-42-treated cells. Moreover, 6-gingerol pretreatment markedly reduced the level of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA), the production of nitric oxide (NO), and the leakage of lactate dehydrogenase (LDH) and increased superoxide dismutase (SOD) activity compared with the Aß1-42 treatment group. In addition, 6-gingerol pretreatment also significantly enhanced the protein levels of phosphorylated Akt (p-Akt) and glycogen synthase kinase-3ß (p-GSK-3ß). Overall, these results indicate that 6-gingerol exhibited protective effects on apoptosis induced by Aß1-42 in cultured PC12 cells by reducing oxidative stress and inflammatory responses, suppressing the activation of GSK-3ß and enhancing the activation of Akt, thereby exerting neuroprotective effects. Therefore, 6-gingerol may be useful in the prevention and/or treatment of AD.

Systematic review and meta-analysis of the bone protective effect of phytoestrogens on osteoporosis in ovariectomized rats.

Phytoestrogens are candidate drugs for the treatment of osteoporosis. Many experiments have been designed to investigate the preventive effects of phytoestrogens for osteoporosis; however, it is easy for a single dissenting result from animal experiments to mislead clinical investigations. Herein, we use meta-analysis to assess the evidence for a protective effect of phytoestrogens on ovariectomized rat models of osteopenia. With respect to osteoporosis, PubMed and Web of Science were searched from January 2000 to March 2013 for relevant studies of phytoestrogens in ovariectomized rats. Two reviewers independently selected and assessed the studies. Data were aggregated using a random effects model. Meta-analysis revealed that the phytoestrogen treatment group demonstrated a significantly higher femur bone mineral density and trabecular bone and lower bone turnover markers (serum alkaline phosphatase and serum osteocalcin) compared with the control ovariectomized group, thus showing a bone protective effect of phytoestrogens in ovariectomized rats. Subsequent sensitivity analyses indicated that the effect of phytoestrogens on serum alkaline phosphatase and serum osteocalcin are not robust. Despite the high heterogeneity in the systematic review of animal experiments, the present results indicated that phytoestrogens may offer the most potential for the prevention of bone loss by reducing the expected loss of trabecular bone and bone mineral density. Their effects are likely due to inhibition of bone resorption, but their benefits on bone formation are still unclear. Further studies are needed to assess the effect of phytoestrogens on bone formation and the efficacy and safety of individual phytoestrogens.

Protective effects of ginger root extract on Alzheimer disease-induced behavioral dysfunction in rats.

The aim of this study was to assess the ability of a traditional Chinese medicinal ginger root extract (GRE) to prevent behavioral dysfunction in the Alzheimer disease (AD) rat model. Rat AD models were established by an operation (OP) in which rats were treated with a one-time intra-cerebroventricuIar injection of amyloid ß-protein (Aß) and continuous gavage of aluminum chloride every day for 4 weeks. GRE was administered intra-gastrically to rats. After 35 days, learning and memory were assessed in all of the rats. Brain sections were processed for immunohistochemistry and Hematoxylin & Eosin (H&E) and Nissl staining. The latency to show significant memory deficits was shorter in the group that received OP with a high dose of GRE (HG)(OP+HG) than in the groups that received OP with a low or moderate dose of GRE (LG, MG)(OP+LG, OP+MG) (p<0.05). The expression of superoxide dismutase (SOD) and catalase (CAT) in the OP+MG and OP+LG groups was up-regulated compared to the OP+HG groups (p<0.05). The rats in the OP+HG groups had lower levels of nuclear factor-κB (NF-κB), interleukin-1ß (IL-1ß), and malondialdehyde (MDA) expression than the rats in the OP+MG and OP+LG groups (p<0.05). This experiment demonstrates that the administration of GRE reverses behavioral dysfunction and prevents AD-like symptoms in our rat model.

Protective effects of Polygonatum sibiricum polysaccharide on ovariectomy-induced bone loss in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: To assess the ability of traditional Chinese medicine Polygonatum sibiricum polysaccharide to prevent bone loss in the ovariectomized rat. MATERIALS AND METHODS: PSP was administered intragastrically to the rats. After 35 days, the total body bone mineral density (BMD) was assessed in all of the rats. All sections were processed for immunohistochemistry and hematoxylin-eosin staining (H.E.). RESULTS: BMD was lower in the ovariectomized group (OVX, 0.163 g/cm(2)), the group that received a moderate dose of PSP on OVX animals (OVX+MP, 0.163 g/cm(2)) and the group that received a low dose of PSP on OVX animals (OVX+LP, 0.162 g/cm(2)) than in the sham-operated group (SHAM, 0.180 g/cm(2)), the OVX+E(2) group (OVX+E(2), 0.176 g/cm(2)) and the group that received a high dose of PSP on OVX animals (OVX+HP, 0.174 g/cm(2)) (P<0.05). Clear arrangements of bone trabeculae were observed in the OVX+E(2) and OVX+HP. The expression of bone morphogenetic proteins (BMP) and basic fibroblast growth factor (bFGF) in the OVX, OVX+MP and OVX+LP was down regulated compared to the SHAM, OVX+E(2) and OVX+HP (P<0.05). The rats in the OVX+E(2) and OVX+HP had lower levels of bone Gla protein (BGP), bone alkaline phosphatase (BALP), tartrate-resistant acid phosphatase (TRAP) and tumor necrosis factor α(TNF-α) expression than the rats in the OVX, OVX+MP and OVX+LP (P<0.05). CONCLUSION: This experiment demonstrates that the administration of PSP to ovariectomized rats reverses bone loss and prevents osteoporosis.