Six herbs in the Plant Genetics Conservation Project that have been used as complementary medicines were chosen on the basis of their medicinal value, namely Terminalia mucronata, Diospyros winitii, Bridelia insulana, Artabotrys harmandii, Terminallia triptera, and Croton oblongifolius. This study aims to evaluate the potential anticancer activity of 50% ethanol-water extracts of these six herbs.

Background: Six plants from Thailand were evaluated for their cytotoxicity and apoptosis induction in human hepatocarcinoma (HepG2) as compared to normal African green monkey kidney epithelial cell lines. Methods: Ethanol-water crude extracts of the six plants were tested with neutral red assay for their cytotoxicity after 24 hours of exposure to the cells. Apoptotic induction was tested in the HepG2 cells with diamidino-2-phenylindole staining. DNA fragmentation, indicative of apoptosis, was analyzed with agarose gel electrophoresis. Alkylation, indicative of DNA damage, was also evaluated in vitro by 4-(4'-nitrobenzyl) pyridine assay. Results: The extract of Pinus kesiya showed the highest selectivity (selectivity index = 9.6) and potent cytotoxicity in the HepG2 cell line, with an IC₅₀ value of 52.0 ± 5.8 μg/ml (mean ± standard deviation). Extract of Catimbium speciosum exerted cytotoxicity with an IC₅₀ value of 55.7 ± 8.1 μg/ml. Crude extracts from Glochidion daltonii, Cladogynos orientalis, Acorus tatarinowii and Amomum villosum exhibited cytotoxicity with IC₅₀ values ranging 100-500 μg/ml. All crude extracts showed different alkylating abilities in vitro. Extracts of P. kesiya, C. speciosum and C. orientalis caused nuclei morphological changes and DNA laddering. Conclusion: The extracts of C. speciosum, C. orientalis and P. kesiya induced apoptosis. Among the three plants, P. kesiya possessed the most robust anticancer activity, with specific selectivity against HepG2 cells.

Neuroinflammation is pathological evidence of Alzheimer’s disease (AD) that likely starts as a host defense response to the damaging effects of the β-amyloid (Aβ) deposits in the brain. The activation of microglia may promote the neurodegenerative process through the release of proinflammatory cytokines, such as interleukin-1β (IL-1β) and tumor necrosis factor-α (TNFα), which may lead to neuronal damage and eventual death. Aged garlic extract (AGE) has been reported to have multiple biological activities, including anti-inflammatory effects. Therefore, the objective of this study was to investigate the effect of AGE on Aβ (1-42)-induced cognitive dysfunction and neuroinflammation. Adult male Wistar rats were given AGE (125, 250, and 500 mg/kg BW, body weight), orally administered, daily for 56 days. They were then injected with 1 μL of aggregated Aβ (1-42) into the lateral ventricles; bilaterally. Seven days later, their recognition memory was evaluated using a novel object recognition (NOR) test. Then the rats were sacrificed to investigate the alteration of microglia cells, IL-1β and TNFα in the cerebral cortex and hippocampus. The results indicated that AGE at doses of 250 and 500 mg/kg BW significantly improved short-term recognition memory in cognitively impaired rats. In addition, AGE significantly minimized the inflammatory response by reducing the activation of microglia and IL-1β to the levels found in the control, which is similar to the results found in Celebrex-treated rats. In conclusion, AGE may be useful for improving the short-term recognition memory and relieve the neuroinflammation in Aβ-induced rats.

Purpose: The aim of this study was to examine the antioxidant activity of ginger extract oral supplement in newly diagnosed cancer patients receiving adjuvant chemotherapy compared to placebo. Patients and methods: Newly diagnosed cancer patients receiving moderate-to-high emetogenic potential adjuvant chemotherapy were randomized to receive either a ginger extract (standardized 6-gingerol 20 mg/day) or a placebo 3 days prior to chemotherapy, which they continued daily. Oxidant/antioxidant parameters, including the activities of superoxide dismutase (SOD) and catalase (CAT) and levels of glutathione peroxidase (GPx), total glutathione (GSH/GSSG), lipid peroxidation products detected as malondialdehyde (MDA) and NO₂^-/NO₃^-, were measured at baseline and at days 1, 22, 43 and 64 after undergoing chemotherapy. Two-sided statistical analysis, with P < 0.05, was used to determine statistical significance. Results: A total of 43 patients were included in the study: 19 and 24 patients were randomly assigned to the ginger group and placebo group, respectively. Antioxidant activity parameters, including SOD, CAT, GPx and GSH/GSSG, were significantly increased at day 64 in the ginger group compared to those in the placebo group, while MDA and NO₂^-/NO₃^- levels were significantly decreased (P < 0.0001). When compared to the baseline, the activities of SOD and CAT and the levels of GPx and GSH/GSSG were significantly higher on day 64 (P = 0.01), while the blood levels of MDA and NO₂^-/NO₃^- were significantly decreased (P < 0.01). Conclusion: Daily supplement of ginger extract started 3 days prior to chemotherapy has been shown to significantly elevate antioxidant activity and reduce oxidative marker levels in patients who received moderate-to-high emetogenic potential chemotherapy compared to placebo.

Valproic acid (VPA) is commonly prescribed as an anticonvulsant and mood stabilizer used in the treatment of epilepsy and bipolar disorder. A recent study has demonstrated that VPA reduces histone deacetylase (HDAC) activity, an action which is believed to contribute to the effects of VPA on neural stem cell proliferation and differentiation which may explain the cognitive impairments produced in rodents and patients. Asiatic acid is a triterpenoid derived from the medicinal plant Centella asiatica. Our previous study has shown that Asiatic acid improves working spatial memory and increases cell proliferation in the sub granular zone of the hippocampal dentate gyrus. In the present study we investigate the effects of Asiatic acid in preventing the memory and cellular effects of VPA. Male Spraque-Dawley rats were orally administered Asiatic acid (30 mg/kg/day) for 28 days, while VPA-treated animals received injections of VPA (300 mg/kg) twice a day from Day 15 to Day 28 for 14 days. Spatial memory was determined using the novel object location (NOL) test and hippocampal cell proliferation and survival was quantified by immuostaining for Ki-67 and Bromodeoxyuridine (BrdU), respectively. The results showed that VPA-treated animals were unable to discriminate between objects in familiar and novel locations. Moreover, VPA significantly reduced numbers of Ki-67 and BrdU positive cells. These results indicate that VPA treatment caused impairments of spatial working memory, cell proliferation and survival in the subgranular zone (SGZ) of the hippocampal dentate gyrus (DG). However, these abnormalities were restored to control levels by co-treatment with Asiatic acid. These data demonstrate that Asiatic acid could prevent the spatial memory and neurogenesis impairments caused by VPA.