Hypoestoxide reduces neuroinflammation and α-synuclein accumulation in a mouse model of Parkinson's disease.

BACKGROUND: Deposition of α-synuclein and neuroinflammation are key pathological features of Parkinson's disease (PD). There is no cure for the disease; however, targeting the pathological features might be available to modulate the disease onset and progression. Hypoestoxide (HE) has been demonstrated as a NF-κB modulator, thereby acting as a potential anti-inflammatory and anti-cancer drug. METHODS: In order to assess the effect of HE in a mouse model of PD, mThy1-α-syn transgenic mice received intraperitoneal (IP) injections of either vehicle or HE (5 mg/kg) daily for 4 weeks. RESULTS: Treatment of HE decreased microgliosis, astrogliosis, and pro-inflammatory cytokine gene expression in α-syn transgenic mice. HE administration also prevented the loss of dopaminergic neurons and ameliorated motor behavioral deficits in the α-syn transgenic mice, and α-synuclein pathology was significantly reduced by treatment of HE. In addition, increased levels of nuclear phosphorylated NF-κB in the frontal cortex of α-syn transgenic mice were significantly reduced by HE administration. CONCLUSIONS: These results support the therapeutic potential of HE for PD and other α-synuclein-related diseases.

21st century natural product research and drug development and traditional medicines.

Natural products and related structures are essential sources of new pharmaceuticals, because of the immense variety of functionally relevant secondary metabolites of microbial and plant species. Furthermore, the development of powerful analytical tools based upon genomics, proteomics, metabolomics, bioinformatics and other 21st century technologies are greatly expediting identification and characterization of these natural products. Here we discuss the synergistic and reciprocal benefits of linking these 'omics technologies with robust ethnobotanical and ethnomedical studies of traditional medicines, to provide critically needed improved medicines and treatments that are inexpensive, accessible, safe and reliable. However, careless application of modern technologies can challenge traditional knowledge and biodiversity that are the foundation of traditional medicines. To address such challenges while fulfilling the need for improved (and new) medicines, we encourage the development of Regional Centres of 'omics Technologies functionally linked with Regional Centres of Genetic Resources, especially in regions of the world where use of traditional medicines is prevalent and essential for health.

Antioxidant and drug detoxification potentials of Hibiscus sabdariffa anthocyanin extract.

The antioxidant and drug metabolizing potentials of Hibiscus anthocyanin extract in CCl(4)- induced oxidative damage of rat liver was investigated. Hibiscus anthocyanin extract effectively scavenge α-diphenyl-ß-picrylhydrazyl (DPPH) radical, superoxide ion, and hydrogen peroxide. It produced a 92% scavenging effect of DPPH radical at a concentration of 2.0 mg/mL. Hibiscus anthocyanin extract produced a 69 and 90% scavenging effect on superoxide ion and hydrogen peroxide, respectively, at 1.0 mg/mL, which compared favorably with the synthetic antioxidant (butylated hydroanisole and α-tocopherol). A reducing power of this anthocyanin was examined using K(3)Fe(CN)(6). Hibiscus anthocyanin extract has reducing power that is approximately 2-fold that of the synthetic antioxidant, butylated hydroanisole. Hibiscus anthocyanin extract produced a significantly increase and completely attenuated the CCl(4)-mediated decrease in antioxidant enzymes (e.g., catalase, superoxide dismutase, glutathione peroxidase, and glutathione reductase). However, the level of nonenzymic antioxidant molecules (i.e., vitamins C and E) were significant preserved by Hibiscus anthocyanin extract. There was an induction of phase II drug-detoxifying enzymes: glutathione S-transferase, NAD(H):quinone oxidoreductase, and uridyl diphosphoglucuronosyl transferase by 65, 45, and 57%, respectively. In view of these properties, Hibiscus sabdariffa anthocyanin extract can act as a prophylactic by intervening as a free radical scavenger both in vitro and in vivo as well as inducing the phase II drug detoxification enzymes.

Acetaminophen perturbed redox homeostasis in Wistar rat liver: protective role of aqueous Pterocarpus osun leaf extract.

This study investigates the in vitro antioxidant potentials and attenuation of acetaminophen-induced redox imbalance by Pterocarpus osun Craib (Fabaceae) leaf in Wistar rat liver. The in vitro antioxidant activity of the extract (0.2-1.0 mg/mL) was evaluated using 2,2-diphenyl-1-picrylhydrazl (DPPH), hydrogen peroxide, superoxide ion, 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonate (ABTS), and ferric ion. The extract (150 and 300 mg/kg body weight) significantly (P<0.05) attenuated the altered liver and serum enzymes of acetaminophen treated animals. Superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glucose-6-phosphate dehydrogenase activities as well as vitamins C and E, and glutathione levels were significantly (P<0.05) elevated by the extract. The activities of uridyl diphosphoglucuronosyl transferase (59%), quinone oxidoreductase (53%), and glutathione S-transferase (73%) significantly increased. The extract of P. osun leaf extract at 1.0mg/mL scavenged the DPPH, hydrogen peroxide, superoxide ion, and ABTS at 94, 98, 92, and 86%, respectively, while ferric ion was significantly reduced. There was attenuation of malondialdehyde and lipid hydroperoxide. The results indicates that P. osun leaves attenuated acetaminophen-induced redox imbalance, possibly acting as free radical scavenger, inducer of antioxidant and drug-detoxifying enzymes, which prevented/reduced lipid peroxidation.

Antioxidant and drug detoxification potential of aqueous extract of Annona senegalensis leaves in carbon tetrachloride-induced hepatocellular damage.

CONTEXT: Despite the myriad uses of Annona senegalensis Pers. (Annonaceae) leaves in folklore medicine of Nigeria, the basis is yet to be substantiated by scientific investigations. OBJECTIVES: To investigate the antioxidant (in vitro and in vivo) and drug detoxification potential of aqueous extract of A. senegalensis leaves in CCl4-induced hepatocellular damage. MATERIALS AND METHODS: In vitro antioxidant activity of the aqueous extract of A. senegalensis leaves was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), H2O2, superoxide ion, 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonate) (ABTS) and ferric ion models while in vivo antioxidant and drug detoxification activities of the extract at 100, 200, and 400 mg/kg body weight were done by assaying the levels of enzymic and non-enzymic indices in CCl4-induced hepatocellular damage. RESULTS: The extract at 1 mg/mL scavenged DPPH, H2O2, superoxide ion, and ABTS radicals, whereas ferric ion was significantly (P <0.05) reduced. The levels of alkaline and acid phosphatases, alanine and aspartate aminotransferases, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase, reduced glutathione, vitamins C and E, glutathione S-transferase, nicotinamide adenine dinucleotide (reduced):Quinone oxidoreductase, uridyl diphosphoglucuronyl transferase, malondialdehyde, and lipid hydroperoxide that decreased in CCl4 treated animals were significantly attenuated by the extract in a manner similar to the animals treated with the reference drug. DISCUSSION AND CONCLUSION: The ability of the aqueous extract of A. senegalensis leaves to scavenge free radicals in vitro and reversal of CCl4-induced hepatocellular damage in rats suggest antioxidant and drug detoxification activities. Overall, this study has justified the rationale behind some of the medicinal uses of the plant in folklore medicine of Nigeria.

Hypoestoxide inhibits tumor growth in the mouse CT26 colon tumor model.

AIM: To evaluate the effect of the natural diterpenoid, hypoestoxide (HE) on the growth of established colon cancer in mice. METHODS: The CT26.WT mouse colon carcinoma cell line was grown and expanded in vitro. Following the expansion, BALB/c mice were inoculated s.c. with viable tumor cells. After the tumors had established and developed to about 80-90 mm(3), the mice were started on chemotherapy by oral administration of HE, 5-fluorouracil (5-FU) or combination. RESULTS: The antiangiogenic HE has previously been shown to inhibit the growth of melanoma in the B16F(1) tumor model in C57BL/6 mice. Our results demonstrate that mean volume of tumors in mice treated with oral HE as a single agent or in combination with 5-FU, were significantly smaller (> 60%) than those in vehicle control mice (471.2 mm(3) vs 1542.8 mm(3), P < 0.01). The significant reductions in tumor burden resulted in pronounced mean survival times (MST) and increased life spans (ILS) in the treated mice. CONCLUSION: These results indicate that HE is an effective chemotherapeutic agent for colorectal cancer in mice and that HE may be used alone or in combination with 5-FU.

In vivo trypanocidal activity of Annona senegalensis Pers. leaf extract against Trypanosoma brucei brucei.

Chemotherapy of African trypanosomiasis still remains far from being satisfactory. There is the urgent need for therapeutic agents that are effective, affordable and accessible to the rural poor in Africa who bear most of the disease burden. Root preparations of Annona senegalensis Pers. is claimed by traditional medicine practitioners to be effective in the treatment of sleeping sickness. Validation of this claim, evaluation of the therapeutic effects of other parts of the plant, and standardization of the preparations are necessary in order to fully exploit the chemotherapeutic potentials of this plant. We have evaluated the chemotherapeutic effects of extracts of the leaves, whole root, root and stem bark of the plant in experimental trypanosomiasis. Crude and partially purified aqueous extracts of the leaves, at a dose of 200mg/kg body weight per day completely cured experimental Trypanosoma brucei brucei infection in mice. Sub-inoculation of blood and cerebrospinal fluid drawn from the cured mice into healthy mice failed to produce any infection within 60 days of post-inoculation. Pre-treatment of healthy mice with the crude extract before infection did not prevent establishment of infection. Administration of 5000mg/kg body weight of the crude extract did not lead to fatality in mice. Preliminary phytochemical screening showed the presence of tannin, phlobatanin, and saponin.

Hypoestoxide, a natural nonmutagenic diterpenoid with antiangiogenic and antitumor activity: possible mechanisms of action.

We have shown previously that hypoestoxide (HE), a natural diterpenoid [a bicyclo (9, 3, 1) pentadecane], is a potent nonsteroidal anti-inflammatory drug. In this report, we demonstrate that HE also inhibits the growth of a variety of human and murine tumor cell lines in vitro at concentrations ranging from 0.3 to 10 microM and was inactive as a mutagen in the Ames test. HE exhibited highly potent (0.3-10 mg/kg dose ranges) activities against B16 melanoma growth in C57BL/6 mice and P388D1 leukemia in C57BL/6 x DBA/2 F(1) mice, respectively. At a low maximal effective dose of 5 mg/kg, HE induced significant in vivo antitumor activities that were better than or comparable with most of the standard chemotherapeutic antiangiogenic agents tested: cortisone acetate, vincristine, bleomycin, Adriamycin, 5-fluorouracil, cyclophosphamide, and etoposide. All of the agents, except vincristine, had much higher maximal effective doses than HE. HE arrested the growth of human Burkitt lymphoma CA46 cells and HeLa (cervical epitheloid carcinoma) cells in the G2-M phase of the cell cycle, which was caused by interference, either direct or indirect, with actin assembly. Thus, the cell cycle arrest occurred at cytokinesis, as demonstrated by an increase in the number of binucleate cells. Moreover, HE inhibited vascular endothelial growth factor-induced cell proliferation in vitro, with an IC(50) of 28.6 microM, and it significantly inhibited basic fibroblast growth factor-induced angiogenesis on the chick chorioallantoic membrane, with an IC50 of 10 microM. Furthermore, HE inhibited endothelial cell migration on vitronectin, collagen, and fibronectin. Besides its activity as a nonsteroidal anti-inflammatory drug, HE also has promise for the chemotherapy of cancer.

Tirucallane triterpenes from the leaf extract of Entandrophragma angolense.

From the leaves of Entandrophragma angolense, three triterpenoidal compounds were isolated and structurally elucidated by mass and NMR spectroscopy. They belong to the tirucallane group but two of them possess the rare seco-ring-A feature. The phytochemical data are discussed from a chemotaxonomic and biogenetic points of view.

Some Nigerian anti-tuberculosis ethnomedicines: a preliminary efficacy assessment.

ETHNOPHARMACOLOGICAL SIGNIFICANCE: Nigerian herbalists possess indigenous ethnomedicinal recipes for the management of tuberculosis and related ailments. A collaborative preliminary modern scientific evaluation of the efficacy of some Nigerian ethnomedicines used by traditional medicine practitioners (TMPs) in the management of tuberculosis and related ailments has been carried out. MATERIALS AND METHODS: Ethnomedicinal recipes (ETMs) were collected from TMPs from locations in various ecological zones of Nigeria under a collaborative understanding. The aqueous methanolic extracts of the ETMs were screened against Mycobacterium bovis, BCG and Mycobacterium tuberculosis strain H37Rv using the broth microdilution method. RESULTS: Extracts of ETMs screened against BCG showed 69% activity against the organism. The activities varied from weak, ≤2500 µg/mL to highly active, 33 µg/mL 64% of the extracts were active against Mycobacterium tuberculosis The activities of the extracts against Mycobacterium tuberculosis varied from weak, ≤2500 µg/mL to highly active, 128 µg/mL. There was 77% agreement in results obtained using BCG or Mycobacterium tuberculosis as test organisms. CONCLUSION: The results show clear evidence for the efficacy of the majority of indigenous Nigerian herbal recipes in the ethnomedicinal management of tuberculosis and related ailments. BCG may be effectively used, to a great extent, as the organism for screening for potential anti-Mycobacterium tuberculosis agents. A set of prioritization criteria for the selection of plants for initial further studies for the purpose of antituberculosis drug discovery research is proposed.

Plasmodium berghei: antiparasitic effects of orally administered hypoestoxide in mice.

Hypoestoxide (HE) is a diterpene isolated from Hypoestes rosea (Acanthaceae), a plant indigenous to Nigeria. Previous studies demonstrated that HE exhibited potent anti-inflammatory and anti-cancer activities in well established animal models but weak in vitro activities in both the anti-inflammation and anti-cancer in vitro screening systems. We now report a similar observation in the in vitro and in vivo screening systems for antimalarial activity. The results indicate that while HE exhibits a relatively weak in vitro activity (IC(50) = 10 microM versus 0.11 microM for chloroquine) against different strains of cultured P. falciparum parasites, the dose of HE required to reduce parasitemia by 90% in Plasmodium berghei-infected mice, is much lower than standard antimalaria drugs (SD(90) = 250 microg/kg versus 5mg/kg for chloroquine). Furthermore, lower doses of HE were much more effective than higher doses in inhibiting parasite development. The implications of these findings are discussed.

Effect of oral administration of aqueous whole extract of cassytha filiformis on haematograms and plasma biochemical parameters in rats.

INTRODUCTION: We evaluated the sub-chronic toxicity of the aqueous herbal extract prepared from Cassytha filiformis and administered daily for 28 days at dose levels (250, 500, and 1000 mg/kg bw) in male wistar albino rats. The LD50 of the aqueous extract was determined. METHODS: The effects on body weights, organ weights, and certain haematological and plasma biochemical parameters were measured as indices of organ toxicity. RESULTS: The aqueous extract did not affect plasma glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT); however, a significant reduction in alkaline phosphatase (ALP) level occurred in all the treated groups. It also did not affect the electrolytes (Na , Cl and K ), total and direct bilirubin, creatinine, and glucose level. The aqueous extract elicited hypercholesterolaemic effects, but it did not affect the Hb, WBC, RBC, PVC, platelets, MCH, MCHC, MCV levels and differential counts (lympocytes, neutrophils, monocytes, eosinophils and basophils). It also reduced the body weight gain and absolute weight of the kidneys. The relative weights of the heart and lungs in some animal groups were equally reduced. The acute toxicological evaluation of the plant extract revealed an oral LD50 value greater than 500 mg/kg bw. CONCLUSION: This study suggests that aqueous extract of C. filiformis administered at normal therapeutic doses is not likely to produce severe toxic effects on some organs or haematological and biochemical indices in rats.

Behavioural effects in rodents of methyl angolensate: a triterpenoid isolated from Entandrophragma angolense.

Behavioral effects of methyl angolensate were investigated in mice and rats. Spontaneous motor activity, pentobarbital sleeping time, amphetamine-stereotyped behaviour, exploratory activity and apomorphine-induced climbing studies in mice were evaluated. The results revealed that methyl angolensate reduced spontaneous motor activity in mice, prolonged the duration of pentobarbital sleeping time in rats and attenuated amphetamine-induced stereotype behaviour in rats. Methyl angolensate also decreased exploratory activity in mice and reduced the rate of apomorphine-induced climbing in mice at the doses tested. It is suggested that methyl angolensate possesses some biologically active principles that are sedative in nature.