Evaluation of antioxidant potential of leaves of Leonotis nepetifolia and its inhibitory effect on MCF7 and Hep2 cancer cell lines

Objective

To investigate the antioxidant and antiproliferative potential of Leonotis nepetifolia (L. nepetifolia) leaves.

Methods

The leaves of L. nepetifolia were subjected to extraction using three different solvents and the antioxidant potential of those extracts were tested by using various in vitro assays. Further, the best screened extract was analyzed for its phytochemical profile by both qualitative and quantitative assays. In order to determine its anti-proliferative activity, the best screened extract was treated with breast and laryngeal cancer cell lines such as MCF-7 cells and Hep2 cells, respectively. The cytotoxicity of the extract was also studied using MTT assay. The inhibitory effect of the extract of leaves of L. nepetifolia on the selected cell-line DNA was determined by DNA fragmentation assay. Also, the extract was subjected to TLC and bioautography analysis.

Results

The DPPH assay showed methanol extract of L. nepetifolia leaves to be more significant in scavenging free radicals with inhibition percentage of 60.57%. From the data obtained, the methanol extract proved to be significant in all anti-oxidant assays and this effect was well comparable with the standard used in the study. The predominant phytochemicals such as phenols and flavonoids were further quantified as 0.107% and 0.089%. The cytotoxicity assay showed that the cell viability increased with increasing concentration of methanol extract. In addition, the extract caused dose dependent damage to the cancer cell lines MCF-7 and Hep2.

Conclusions

Our study suggests that the leaves of L. nepetifolia were significant in scavenging free radicals and causing damage to proliferative cells. Further mechanistic studies would help in proving the efficiency of the selected plant under in vivo conditions.     

Antinociceptive activity of α4β2* neuronal nicotinic receptor agonist A-366833 in experimental models of neuropathic and inflammatory pain

Nerve injury, diabetes and cancer therapies are often associated with painful neuropathy. The mechanism underlying neuropathic pain remains poorly understood. The current therapies have limited efficacy and are associated with dose-limiting side effects. Compounds which act at nicotinic acetylcholine receptors have also been reported to show antinociceptive activity. Among those, tebanicline (ABT-594) a potent nicotinic acetylcholine receptor agonist demonstrated analgesic effects across a broad range of preclinical models of nociceptive and neuropathic pain. Another nicotinic acetylcholine receptor agonist, 5-[(1R,5S)-3,6-Diazabicyclo[3.2.0]heptan-6-yl]nicotinonitrile (A-366833) from the same group produced significant antinociceptive effects in writhing pain (abdominal constriction), acute thermal pain (hot box), persistent chemical pain (formalin induced) and neuropathic pain. In the present study, we have demonstrated the efficacy of A-366833 in rat models of chronic constriction injury, partial sciatic nerve ligation, spinal nerve ligation, diabetes, chemotherapy induced neuropathic pain and complete Freund's adjuvant induced inflammatory pain. A-366833 (1, 3 and 6 mg/kg) produced significant antihyperalgesic effects in partial sciatic nerve ligation, chronic constriction injury and spinal nerve ligation models. In the diabetic and chemotherapy induced neuropathic models compound exerted antinociceptive activity and reduction in the mechanical hyperalgesia was observed. A-366833 dose dependently attenuated mechanical hyperalgesia in complete Freund's adjuvant induced inflammatory pain model. These results demonstrated broad-spectrum antinociceptive properties of A-366833 in both neuropathic and inflammatory pain models.     

Performance Evaluation of Computer Aided Diagnostic Tool (CAD) for Detection of Ultrasonic Based Liver Disease

Recent advances in digital imaging technology have greatly enhanced the interpretation of critical/pathology conditions from the 2-dimensional medical images. This has become realistic due to the existence of the computer aided diagnostic tool. A computer aided diagnostic (CAD) tool generally possesses components like preprocessing, identification/selection of region of interest, extraction of typical features and finally an efficient classification system. This paper enumerates on development of CAD tool for classification of chronic liver disease through the 2-D image acquired from ultrasonic device. Characterization of tissue through qualitative treatment leads to the detection of abnormality which is not viable through qualitative visual inspection by the radiologist. Common liver diseases are the indicators of changes in tissue elasticity. One can show the detection of normal, fatty or malignant condition based on the application of CAD tool thereby, further investigation required by radiologist can be avoided. The proposed work involves an optimal block analysis (64 × 64) of the liver image of actual size 256 × 256 by incorporating Gabor wavelet transform which does the texture classification through automated mode. Statistical features such as gray level mean as well as variance values are estimated after this preprocessing mode. A non-linear back propagation neural network (BPNN) is applied for classifying the normal (vs) fatty and normal (vs) malignant liver which yields a classification accuracy of 96.8%. Further multi classification is also performed and a classification accuracy of 94% is obtained. It can be concluded that the proposed CAD can be used as an expert system to aid the automated diagnosis of liver diseases.     

Anti-angiogenic efficacy of grape seed extract in endothelial cells

The present study is focused on the investigation of in vitro angiogenic potential of grape seed extract (GSE). Human umbilical vein endothelial cells (HUVEC) in culture were used to assess the effect of GSE on proliferation, survival, matrix metalloproteinases (MMPs) secretion and capillary tube formation. Our data show that GSE significantly inhibited cell growth (< or =91%, P<0.001) and cell viability (< or =64%, P<0.005) of HUVEC. Further studies by BrdU incorporation and annexin V staining showed that GSE strongly inhibits DNA synthesis (< or =76%, P<0.001) and induces apoptotic cell death (< or =42.8% versus control 2.6%, P<0.05) in HUVEC, respectively. Similar GSE treatment decreased secreted levels of MMP-2 from HUVEC. GSE also inhibited capillary tube formation on Matrigel by endothelial cells in a dose-dependent manner. These findings suggest that GSE possesses an anti-angiogenic potential, which is associated with its antiproliferative, proapoptotic and inhibition of MMP-2 secretion in endothelial cells. Further studies are warranted to evaluate the in vivo anti-angiogenic efficacy of GSE for its possible usefulness in the inhibition of tumor angiogenesis.     

Silibinin sensitizes human prostate carcinoma DU145 cells to cisplatin- and carboplatin-induced growth inhibition and apoptotic death

In several recent studies, we have shown that silibinin inhibits the growth of human prostate cancer cells (PCA) both in vitro and in vivo. Here, we investigated the effect of silibinin in combination with cisplatin and carboplatin on human PCA DU145 cell growth and apoptosis. Cisplatin alone at 2 microg/ml dose produced 48% cell growth inhibition, whereas a combination with 50-100 microM silibinin resulted in 63-80% (p<0.05-0.001) growth inhibition. Similarly, compared to 68% growth inhibition at 20 microg/ml carboplatin, addition of 50-100 microM doses of silibinin caused 80-90% inhibition (p<0.005-0.001). In the studies assessing the effect of these combinations on cell cycle progression, a combination of cisplatin or carboplatin with silibinin resulted in a stronger G2-M arrest, compared to these agents alone showing a moderate G2-M and G1 arrests in case of cisplatin and silibinin, and a complete S phase arrest with carboplatin, respectively. A stronger G2-M arrest by these combinations was accompanied by a substantial decrease in the levels of cdc2, cyclin B1 and cdc25C. Silibinin/platinum compound combinations were also effective in inducing apoptosis where cisplatin and carboplatin when combined with silibinin enhanced apoptosis from 8 to 15% and from 20 to 40%, respectively. Apoptosis induction was further confirmed by PARP and caspases 3, 9 and 7 whose cleaved levels were also enhanced by combination treatment. In addition, there was a significant increase in cytochrome c release in the cytosol following treatment of DU145 cells with these combinations. Together, these results show a substantial increase in the efficacy of platinum compounds on human PCA cells, when combined with silibinin, which provide a rationale for further investigations with these combinations.     

Rapid Point-of-Care Test for Determination of C-Peptide Levels

C-peptide is co-secreted with insulin and is not subject to hepatic clearance and thus reflects functional β-cell mass. Assessment of C-peptide levels can identify individuals at risk for or with type 1 diabetes with residual β-cell function in whom β cell-sparing interventions can be evaluated, and can aid in distinguishing type 2 diabetes from Latent Autoimmune Diabetes in Adults and late-onset type 1 diabetes. To facilitate C-peptide testing, we describe a quantitative point-of-care C-peptide test. C-peptide levels as low as 0.2 ng/ml were measurable in a fingerstick sample, and the test was accurate over a range of 0.17 to 12.0 ng/ml. This test exhibited a correlation of r = 0.98 with a high-sensitivity commercial ELISA assay and a correlation of r = 0.90 between matched serum and fingerstick samples.     

Agaricus blazei extract attenuates rotenone-induced apoptosis through its mitochondrial protective and antioxidant properties in SH-SY5Y neuroblastoma cells

The present study was aimed to find out the effect of Agaricus blazei mushroom extract against rotenone-induced cellular model. SH-SY5Y neuroblastoma cells are divided into four experimental groups (control, rotenone (100?nM), A. blazei (5?μg/ml) + rotenone (100?nM), and A. blazei alone treated) based on MTT assay, cells were allowed to measure the ROS, TBARS levels, and antioxidants activities. Finally, mitochondrial transmembrane potential (MMP) and expressions of apoptotic proteins were also analyzed. Pre-treatment with A. blazei significantly enhanced cell viability, attenuated rotenone-induced ROS, MMP, and apoptosis. Our results indicated that anti-apoptotic properties of this natural compound due to its antioxidant and mitochondrial protective function protect rotenone-induced cytotoxicity. Therefore, it may be concluded that A. blazei can be further developed as a promising drug for the treatment of Parkinson’s disease (PD).