Apoptosis-inducing anti-proliferative and quantitative phytochemical profiling with in silico study of antioxidant-rich Leea aequata L. leaves.

Natural products have been important parts of traditional medicine since ancient times, with various promising health effects. Leea aequata (L. aequata), a natural product, has been widely used for treating several diseases due to its promising pharmacological activities. Therefore, the present study aimed to explore the phytochemical profiling and molecular docking of the antioxidant-rich part of L. aequata leaves and its antiproliferative activity. L. aequata leaves were extracted with methanol, followed by fractionation with the respective solvents to obtain the petroleum ether, chloroform, ethyl acetate, and aqueous fractions. The antioxidant activity was evaluated by spectrophotometric methods. The cytotoxic and antiproliferative activities were detected using MTT colorimetric and confocal microscopy methods, respectively. Phytochemical compositions were analyzed using gas chromatography‒mass spectrometry analysis. Computer aided (molecular docking SwissADME, AdmetSAR and pass prediction) analyses were undertaken to sort out the best-fit phytochemicals present in the plant responsible for antioxidant and anticancer effects. Among the fractions, the ethyl acetate fraction was the most abundant polyphenol-rich fraction and showed the highest antioxidant, reducing power, and free radical scavenging activities. Compared to untreated MCF-7 cells, ethyl acetate fraction-treated MCF-7 cells showed an increase in apoptotic characteristics, such as membrane blebbing, chromatin condensation, and nuclear fragmentation, causing apoptosis and decreased proliferation of HeLa and MCF-7 cells. Furthermore, gas chromatography mass spectrometry data revealed that the ethyl acetate fraction contained 16 compounds, including methyl esters of long-chain fatty acids, which are the major chemical constituents. Moreover, hexadecanoic acid, methyl ester; 9-octadecenoic acid (Z)-, methyl ester; 9,12-octadecadienoic acid, methyl ester (Z, Z) and phenol, 2,4-bis(1,1-dimethylethyl) are known to have antioxidant and cytotoxic activity, as confirmed by computer-aided models. A strong correlation was observed between the antioxidant and polyphenolic contents and the anticancer activity. In conclusion, we explored the possibility that L. aequata could be a promising source of antioxidants and anticancer agents with a high phytochemical profile.

Hypnea musciformis-mediated Ag/AgCl-NPs inhibit pathogenic bacteria, HCT-116 and MCF-7 cells' growth in vitro and Ehrlich ascites carcinoma cells in vivo in mice.

In the present study, Ag/AgCl-NPs were biosynthesised using Hypnea musciformis seaweed extract; NPs synthesis was confirmed by a change of colour and observation of a razor-sharp peak at 424 nm by UV-visible spectroscopy. Synthesised nanoparticles were characterised by transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray powder diffraction and Fourier transform infrared spectroscopy. Bacterial cell growth inhibition proves that the Ag/AgCl-NPs have strong antibacterial activity and cell morphological alteration was observed in treated bacterial cells using propidium iodide (PI). Ag/AgCl-NPs inhibited Ehrlich ascites carcinoma (EAC) cells, colorectal cancer (HCT-116) and breast cancer (MCF-7) cell line in vitro with the IC50 values of 40.45, 24.08 and 36.95 µg/ml, respectively. Initiation of apoptosis in HCT-116 and MCF-7 cells was confirmed using PI, FITC-annexin V and Hoechst 33342 dye. No reaction oxygen species generation was observed in both treated and untreated cell lines. A significant increase of ATG-5 gene expression indicates the possibility of autophagy cell death besides apoptosis in MCF-7 cells. The initiation of apoptosis in EAC cells was confirmed by observing caspase-3 protein expression. Ag/AgCl-NPs inhibited 22.83% and 51% of the EAC cell growth in vivo in mice when administered 1.5 and 3.0 mg/kg/day (i.p.), respectively, for 5 consequent days.

Moringa oleifera seed lectin inhibits Ehrlich ascites carcinoma cell growth by inducing apoptosis through the regulation of Bak and NF-κB gene expression.

A Moringa oleifera seed lectin (MOSL) was purified by using chitin column with the molecular mass of 17±1kDa. The lectin agglutinated mouse, cow and human erythrocytes and the hemagglutination activity was inhibited by methyl-α-d-mannopyranoside, methyl-ß-d-galactopyranoside, lactose and glucose. The lectin exhibited 100% hemagglutination activity at the pH range from 8.0 to 9.0 and temperature range from 30 to 60°C. Additionally, the lectin gradually lost its activity in the presence of urea but the activity abolish completely when treated with EDTA. MOSL showed mild toxicity against brine shrimp nauplii with a LC50 value of 131.0µg/ml. Antiproliferative activity was studied against Ehrlich ascites carcinoma (EAC) cells and 71.08% cell growth inhibition was observed in vitro at 200µg/ml. The lectin was injected (i.p.) into EAC mice at the doses of 2.0 and 4.0mg/kg/day for five consecutive days and 25.38% and 55% of cell growth inhibition was observed, respectively. MOSL caused the cell cycle arrest at G2/M phase as determined by FACS flow cytometry. The cell growth inhibition was due to the induction of apoptosis in the EAC cells which was confirmed by cell morphological study, caspase-3 inhibitor and activation of Bak and suppression of Bcl-2 and NF-κB genes expression.

Solanum tuberosum lectin inhibits Ehrlich ascites carcinoma cells growth by inducing apoptosis and G2/M cell cycle arrest.

Recently, a lectin was purified from the potato cultivated in Bangladesh locally known as Sheel. In the present study cytotoxicity of the lectin against Ehrlich ascites carcinoma (EAC) cells was studied by MTT assay in vitro in RPMI-1640 medium and 8.0-36.0 % cell growth inhibition was observed at the range of 2.5-160 µg/ml protein concentration when incubated for 24 h. The lectin-induced apoptosis in EAC cells was confirmed by fluorescence and optical microscope. The apoptotic cell death was also confirmed by using caspase inhibitors. Cells growth inhibition caused by the lectin (36 %) was remarkably decreased to 7.6 and 22.3 % respectively in the presence of caspase-3 and -8 inhibitors. RT-PCR was used to evaluate the expression of apoptosis-related genes Bcl-X, p53, and Bax. An intensive expression of Bcl-X gene was observed in untreated control EAC cells with the disappeared of the gene in Sheel-treated EAC cells. At the same time, Bax gene expression appeared only in Sheel-treated EAC cells and the expression level of the p53 gene was increased remarkable after the treatment of EAC cells with the lectin. The lectin showed strong agglutination activity against EAC cells. Flow cytometry was used to study the cell cycle phases of EAC cells and it was observed that the lectin arrested the G2/M phase. In conclusion, Sheel lectin inhibited EAC cells growth by inducing apoptosis.

Purification and characterization of a novel chitinase from Trichosanthes dioica seed with antifungal activity.

Chitinases are a group of enzymes that show differences in their molecular structure, substrate specificity, and catalytic mechanism and widely found in organisms like bacteria, yeasts, fungi, arthropods actinomycetes, plants and humans. A novel chitinase enzyme (designated as TDSC) was purified from Trichosanthes dioica seed with a molecular mass of 39±1 kDa in the presence and absence of ß-mercaptoethanol. The enzyme was a glycoprotein in nature containing 8% neutral sugar. The N-terminal sequence was determined to be EINGGGA which did not match with other proteins. Amino acid analysis performed by LC-MS revealed that the protein was rich in leucine. The enzyme was stable at a wide range of pH (5.0-11.0) and temperature (30-90 °C). Chitinase activity was little bit inhibited in the presence of chelating agent EDTA (ethylenediaminetetraaceticacid), urea and Ca(2+). A strong fluorescence quenching effect was found when dithiothreitol and sodium dodecyl sulfate were added to the enzyme. TDSC showed antifungal activity against Aspergillus niger and Trichoderma sp. as tested by MTT assay and disc diffusion method.

A p-menth-1-ene-4,7-diol (EC-1) from Eucalyptus camaldulensis Dhnh. triggers apoptosis and cell cycle changes in Ehrlich ascites carcinoma cells.

Anticancer activities of p-menth-1-ene-4,7-diol (EC-1) isolated from Eucalyptus camaldulensis Dhnh. were studied on Ehrlich ascites carcinoma (EAC) cells by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay. Anticancer activities also analyzed in EAC-bearing mice by assessment of cancer growth inhibition, changes in cancer volume, changes in life span, and hematological parameters. Apoptosis was analyzed by fluorescence microscope, DNA fragmentation assay, and flow cytometry. The expression of apoptosis-related genes, Bcl-2, Bcl-X, PARP-1, p53, and Bax, were analyzed using polymerase chain reaction (PCR). EC-1 significantly inhibited proliferation of EAC cells in vivo and restored the altered hematological parameters of EAC-bearing mice. Cytological observation by fluorescence microscope showed apoptosis of EAC cells upon treatment with EC-1. Also, DNA fragmentation assay revealed EAC cells' apoptosis following EC-1 treatment. Increased mRNA expressions of p53 and Bax genes and negative expressions of Bcl-2 and Bcl-X were observed in cells treated with EC-1. These findings confirmed the induction of apoptosis by EC-1. In addition, MTT assay showed dose-dependent anticancer activity of EC-1 against EAC cell. Cell cycle analysis revealed that EC-1 treatment caused suppression of EAC cells at S phase. To conclude, EC-1 is a novel anticancer compound and showed antiproliferative and apoptotic activities in cellular and mice models.

Purification of a novel chitin-binding lectin with antimicrobial and antibiofilm activities from a bangladeshi cultivar of potato (Solanum tuberosum).

A new chitin-binding lectin was purified from a Bangladeshi cultivar 'Deshi' of potato (Solanum tuberosum L.) through anion-exchange and affinity chromatographies using a chitin column. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) showed the molecular mass of the lectin as 20,000 Daltons. This molecular mass was almost half of the molecular masses of chitin-binding lectins derived from other potatoes. The lectin showed both bactericidal and growth-inhibiting activities against Gram-positive (Listeria monocytogenes) and Gram-negative (Escherichia coli, Salmonella enteritidis and Shigella boydii) pathogenic bacteria. It also showed antifungal activity against Rhizopus spp., Penicillium spp. and Aspergillus niger. Biofilm produced by the bacterium Pseudomonas aeruginosa was dose-dependently reduced by 5-20% in 24 h after administration of the lectin, which was attributed to the glycan-binding property of the lectin having affinity to GlcNAc polymers. It was the first observation that any potato lectin prevented biofilm formation by P. aeruginosa and, therefore, could have possible applications in clinical microbiology and biomedical science.

Antibacterial activity of Kaempferia rotunda rhizome lectin and its induction of apoptosis in Ehrlich ascites carcinoma cells.

The tuberous rhizome Kaempferia rotunda Linn. has been used as food and traditional medicinal plant, and the purified K. rotunda lectin (KRL) showed antiproliferative activity against Ehrlich ascites carcinoma cells [1]. In the present study, KRL showed agglutination activity against Escherichia coli and Staphylococcus aureus, with partial inhibition of their growth. MTT assay was used to investigate the effect of KRL on EAC cells in vitro in RPMI-1640 medium, and it was found that lectin inhibited 6.2-50.5% cell growth at the range of 7.5-120 µg/ml protein concentration. The cell cycle arrest at G0/G1 phase of EAC cells was also determined by flow cytometry after treatment with lectin. The apoptotic cell morphological changes of the treated EAC cells were confirmed by fluorescence and optical microscope. In the presence of caspase-3 inhibitor, the cell growth inhibition of the lectin was reduced significantly. RT-PCR was used to evaluate the expression of apoptosis-related genes, bcl-2, bcl-X, and bax. Bax gene expression was intensively increased with the despaired of bcl-X gene expression and significant decrease of bcl-2 gene expression in the cells treated with KRL. Thus, lectin induced apoptotic cell death in Ehrlich ascites carcinoma cells.

Pea lectin inhibits growth of Ehrlich ascites carcinoma cells by inducing apoptosis and G2/M cell cycle arrest in vivo in mice.

Pea (Pisum sativum L.) lectin is known to have interesting pharmacological activities and of great interest on biomedical research. In the current research pea lectin was purified followed by ion exchange chromatography on DEAE column and affinity chromatography on glucose-sepharose column. The lectin shown 11.7-84% inhibitory effect against Ehrlich ascites carcinoma (EAC) cells at the concentration range of 8-120 µg/ml in RPMI 1640 medium as determined by MTT assay. Pea lectin was also shown 63% and 44% growth inhibition against EAC cells in vivo in mice when administered 2.8 mg/kg/day and 1.4 mg/kg/day (i.p.) respectively for five consequent days. When Pea lectin injected into the EAC bearing mice for 10 days its significantly increased the hemoglobin and RBC with the decreased of WBC levels toward the normal. Apoptotic cell morphological change of the treated EAC cells of mice was determined by fluorescence and optical microscope. Interestingly, cell growth inhibition of the lectin was significantly reduced in the presence of caspase inhibitors. Treatment with the lectin caused the cell cycle arrest at G2/M phase of EAC cells which was determined by flow cytometry. The expression of apoptosis-related genes, Bcl-2, Bcl-X and Bax was evaluated by reverse transcriptase polymerase chain reaction (RT-PCR). Intensive increase of Bax gene expression and totally despaired of Bcl-2 and Bcl-X gene expression were observed in the cells treated with Pea lectin for five consecutive days.

A new lectin from the tuberous rhizome of Kaempferia rotunda: isolation, characterization, antibacterial and antiproliferative activities.

A lectin (designated as KRL) was purified from the extracts of Kaempferia rotunda Linn. tuberous rhizome by glucose-sepharose affinity chromatography. KRL was determined to be a 29.0 ± 1.0 kDa polypeptide by SDS-PAGE under both reducing and non-reducing conditions. KRL was a divalent ion dependent glycoprotein with 4% neutral sugar which agglutinated different groups of human blood cells. Methyl-α-D-mannopyranoside, D-mannose and methyl-α-D-glucopyranoside were the most potent inhibitors. N-terminal sequence of KRL showed similarity to some mannose/ glucose specific lectins but the main differences with their molecular masses and sugar content. KRL lost its activity markedly in the presence of denaturants and exhibited high agglutination activity from pH 6.0 to 8.2 and temperature 30 to 60° C. The lectin showed toxicity against brine shrimp nauplii with the LC50 value of 18 ± 6 µg/ml and strong agglutination activity against seven pathogenic bacteria. KRL inhibited the growth of six bacteria partially and did not show antifungal activity. In addition, antiproliferative activity against Ehrlich ascites carcinoma (EAC) cells showed 51% and 67% inhibition in vivo in mice administered 1.25 mg/kg/day and 2.5 mg/kg/day of KRL respectively by injection for five days.