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Food fermentation has been a tradition for decades due to its immense benefits. Lactic acid bacteria are known to possess probiotic potential due to various chemical antimicrobial substances they produce. This research was aimed at isolating Lactobacillus spp. from locally fermented locust beans and screening the isolates for their probiotic potential. A total of 20 samples of fermented locust beans (P. biglobosa) were collected and processed. The samples were inoculated onto de-Mann Rogosa Sharpe (MRS) media and incubated anaerobically. The isolates with characteristic colonial morphology of Lactobacillus sp. were characterized using Gram staining and biochemical tests. Lactobacillus spp. isolates were screened in-vitro for probiotic potential using the following parameters, tolerance of low pH, bile tolerance and antimicrobial activity. Four isolates of Lactobacillus species consisting of Lactobacillus fermentum and Lactobacillus plantarum were isolated from different fermented locust beans. All isolates showed tolerance to low pH and bile concentration of 3.04 and 0.3%, respectively. The Lactobacillus species isolates showed varying antibacterial activity against all test bacteria with isolate S06 (L. plantarum) showing the highest degree of antibacterial activity. In conclusion, the Lactobacillus species isolated from fermented locust beans can serve as probiotic candidate. [ABSTRACT FROM AUTHOR]

Context: Carissa edulis Vahl (Apocynaceae) is used in Nigerian folk medicine to manage a plethora of diseases including epilepsy, cancer, and inflammation; its efficacy is widely acclaimed among communities of northern Nigeria. Objective: This study establishes anticonvulsant activities of aqueous fraction of ethanol root bark extract of Carissa edulis (RAF) and sub-fractions (S1 and S2) in animal models. Materials and methods: We evaluated the acute toxicity of the RAF, S1 and S2, and the anticonvulsant activity using pentylenetetrazole (PTZ), picrotoxin, strychnine, N-methyl- d-aspartate (NMDA), isoniazid (INH), and aminophylline-induced seizures in mice. Their effects on maximal electroshock (MES) and kindling-induced seizures were studied in chicks and in rats, respectively, and in the electrophysiological study. The doses used for RAF were 150, 300, and 600 mg/kg while S1 and S2 were 250, 500, and 1000 mg/kg. Both RAF and sub-fractions were administered once during the experiment. Results: The intraperitoneal LD50 of the RAF was estimated to be 2222.61 mg/kg and that of the S1 and S2 were above 5000 mg/kg. RAF protected the mice by 50% while sub-fractions by 16.67% against PTZ-induced seizures. RAF offered 33.33 and 16.67% protection against strychnine and NMDA models, respectively. However, RAF offered 66.67-33.33% protections against aminophylline-induced seizures at doses of 150 and 600 mg/kg, but RAF, S1, and S2 had no effect on MES-induced seizures. Discussion and conclusion: Our results validate the use of the plant traditionally in the management of epilepsy, thus supporting the appraisal of biologically active components of this plant as antiepileptic agents. [ABSTRACT FROM AUTHOR]

Securinega virosa (Roxb ex. Willd) Baill. is a plant which is commonly used in African traditional medicine in management of mental illness. Previous study showed that the crude methanolic root bark extract of the plant possesses antipsychotic activity. In this study, the antipsychotic potential of the residual aqueous fraction of the plant was evaluated using two experimental models, apomorphine induced stereotypic climbing behaviour and swim induced grooming, all in mice. The effect of the fraction on haloperidol-induced catalepsy was also evaluated. The fraction significantly reduced the mean climbing score at the highest dose tested (500 mg/kg). In the swim-induced grooming test, the fraction significantly and dose-dependently (125-500 mg/kg) decreased the mean number and mean duration of swim-induced grooming activity in mice. Similarly, the standard haloperidol (1 mg/kg) significantly ( p < 0.001) decreased the mean grooming episodes and duration. However, the fraction did not significantly potentiate haloperidol-induced catalepsy. These results suggest that the residual aqueous fraction of methanol root bark extract of Securinega virosa contains biological active principle with antipsychotic potential. [ABSTRACT FROM AUTHOR]

Context: Decoctions of Randia nilotica Stapf. (Rubiaceae) have been used in the Nigerian traditional medicine for the management of epilepsy, anxiety, depression and psychosis for many years and their efficacies are widely acclaimed among the rural communities of Northern Nigeria. Objective: The aim of this study is to establish whether the saponins present in R. nilotica are responsible for its acclaimed beneficial effects in Nigerian traditional medicine. Materials and methods: The behavioural properties of the saponin-rich fraction (SFRN) of R. nilotica stem bark were studied on hole-board, diazepam-induced sleep, rota-rod and beam-walking in mice. The anticonvulsant properties of SFRN were also examined on maximal electroshock, pentylenetetrazole- and strychnine-induced seizures in mice. Results: The intraperitoneal LD50 of SFRN in mice and rats were estimated to be 11.1 and 70.7 mg/kg, respectively. SFRN significantly prolonged the duration of diazepam-induced sleep; diminished head dip counts in the hole-board test and protected mice against maximal electroshock seizures. SFRN failed to protect mice against pentylenetetrazole- and strychnine-induced seizures; and had no effect on motor coordination on the rota-rod treadmill at the doses tested. SFRN significantly decreased the number of foot slips in the beam-walking assay in mice with no effect on time to reach the goal box. Discussion and conclusion: This study provides evidence of the psychopharmacological effects of SFRN, thus supporting further development of the psychoactive components as remedies for epilepsy. [ABSTRACT FROM AUTHOR]

Glioblastoma multiforme (GBM) is the highest grade of astrocytoma. GBM pathogenesis has been linked to receptor tyrosine kinases and kinases further down signal-transduction pathways – in particular, members of the protein kinase C (PKC) family. The expression and activity of various PKC isoforms are increased in malignant astrocytomas, but not in non-neoplastic astrocytes. This suggests that PKC activity contributes to tumor progression. The level of PKC-η expressed correlates with the degree of phorbol-12-myristate-13-acetate (PMA)-induced proliferation of two glioblastoma cell lines, U-1242 MG and U-251 MG. Normally, U-1242 cells do not express PKC-η, and PMA inhibits their proliferation. Conversely, PMA increases proliferation of U-1242 cells that are stably transfected with PKC-η (U-1242-PKC-η). PMA treatment also stimulates proliferation of U-251 cells, which express PKC-η. Here, we determined that extracellular signal-regulated kinase (ERK) and Elk-1 are downstream targets of PKC-η. Elk-1-mediated transcriptional activity correlates with the PKC-η-mediated mitogenic response. Pretreatment of U-1242-PKC-η cells with inhibitors of PKC or MAPK/ERK kinase (MEK) (bisindolyl maleimide (BIM) or U0126, respectively) blocked both PMA-induced Elk-1 transcriptional activity and PMA-stimulated proliferation. An overexpressed dominant-negative PKC-η reduced the mitogenic response in U-251 cells, as did reduction of Elk-1 by small interfering RNA. Taken together, these results strongly suggest that PKC-η-mediated glioblastoma proliferation involves MEK/mitogen-activated protein (MAP) kinase phosphorylation, activation of ERK and subsequently of Elk-1. Elk-1 target genes involved in GBM proliferative responses have yet to be identified.Oncogene (2007) 26, 2885–2893. doi:10.1038/sj.onc.1210090; published online 4 December 2006 [ABSTRACT FROM AUTHOR]

Previously, we have shown that PKC-η (protein kinase C-eta) positively regulates glioblastoma proliferation and confers resistance to irradiation-induced apoptosis. In this study, we investigated the efficacy of rapamycin in inhibiting cell proliferation in two glioblastoma cell lines U-251MG (PKC-η expressing) and U-1242MG (PKC-η deficient) following PKC-η activation. In U-251MG cells, rapamycin (10 nM) treatment was less effective as an antiproliferative agent when cells were concurrently stimulated with 10% serum and phorbol 12-myristate 13-acetate (PMA, 100 nM), a potent activator of PKC isozymes. Rapamycin-insensitive growth was owing to PKC-η, as U-1242MG and U-251MG cells infected with a kinase-dead form of PKC-η (U-251kr) were susceptible to rapamycin-induced inhibition of cell proliferation. Furthermore, U-251MG cells transfected with PKC-η antisense oligonucleotides were sensitive to rapamycin. PKC-η-expressing cells stimulated with PMA maintained p70S6K phosphorylation on Thr389 and phosphorylation of rpS6 (ser235/36), suggesting p70S6K kinase activity was still intact. Inhibition of p70S6K expression with small interfering RNA oligonucleotides inhibited cell proliferation greater than 50% in the presence of a combination of PMA and serum. Additionally, p70S6K co-precipitated with PKC-η, suggesting a physical interaction between PKC-η and p70S6K regulates the observed phosphorylation. Taken together, these data demonstrate that rapamycin-insensitive glioblastoma proliferation involves PKC-η signaling.Oncogene (2007) 26, 407–414. doi:10.1038/sj.onc.1209791; published online 10 July 2006 [ABSTRACT FROM AUTHOR]

Primary glioblastomas (GBMs) commonly overexpress the oncogene epidermal growth factor receptor (EGFR), which leads to increased Ras activity. FTA, a novel Ras inhibitor, produced both time- and dose-dependent caspase-mediated apoptosis in GBM cell lines. EGFR-mediated increase in 3H-thymidine uptake was inhibited by FTA. FACS analysis was performed to determine the percent of apoptotic cells. The sub-Go population of GBM cells was increased from 4.5 to 13.8% (control) to over 45–53.6% in FTA-treated cells within 24 h. Furthermore, FTA also increased the activities of both caspase-3 and -9, and PARP cleavage. Treatment of GBMs with FTA before or after EGF addition to the cultures blocked phosphorylation of Akt and mitogen-activated protein kinases (MAPK). FTA also significantly reduced the amount of EGF-induced Ras-GTP as reflected by a decrease in the level of Ras bound to Raf-RBD-GST. This study demonstrates that inhibition of Ras methylation may provide a therapeutic target for the treatment of GBMs overexpressing EGFR.Cell Death and Differentiation (2006) 13, 642–651. doi:10.1038/sj.cdd.4401783; published online 21 October 2005 [ABSTRACT FROM AUTHOR]