Antidepressant-like effect of dehydrozingerone from Zingiber officinale by elevating monoamines in brain: in silico and in vivo studies.

BACKGROUND: Dehydrozingerone (DHZ) is an active ingredient of Zingiber officinale and structural half analogue of curcumin. In the present study, DHZ was evaluated for monoamine oxidase (MAO) inhibitory activity in silico and antidepressant activity in vivo. METHOD: The binding affinity of DHZ with MAO-A (PDB ID: 2Z5Y) was assessed using Schrodinger's Maestro followed by free energy calculation, pharmacokinetic property prediction using Qikprop and Molecular dynamics simulation using Desmond. In vivo antidepressant activity of DHZ was evaluated on C57 BL/6 male mice using Escilatopram as the standard antidepressant. Open field test (OFT), forced swimming test (FST) and tail suspension test (TST) were used to evaluate the antidepressant effect of the drugs on days 1 and 7. Following the behavioural study, neurotransmitters (noradrenaline, dopamine and serotonin) were estimated using liquid chromatography-mass spectrometry. RESULTS: DHZ demonstrated a greater binding affinity for the MAO-A enzyme compared to moclobemide in silico. Immobility in TST and FST were significantly (p < 0.05) reduced in vivo with 100mg/kg DHZ as compared to respective controls. DHZ treatment was more effective 1 h post treatment compared to vehicle control. A significant increase in levels of neurotransmitters was observed in mice brain homogenate in response to DHZ treatment, reassuring its antidepressant-like potential. CONCLUSION: DHZ demonstrated MAO-A inhibition in silico, and the increased neurotransmitter levels in the brain in vivo were associated with an antidepressant-like effect.

Modelling of pretreatment and saccharification with different feedstocks and kinetic modeling of sorghum saccharification.

Experiments have been performed for pretreatment of sorghum, wheat straw and bamboo through high temperature alkali pretreatment with different alkaline loading and temperatures, and the data on extent of delignification in terms of the final compositions of cellulose, hemicellulose and lignin have been generated. Further, enzymatic saccharification has been carried out in all the cases to find the extent of conversion possible after 72h. The effect of different operating parameters on the extent of delignification and cellulose conversion are evaluated. This data is employed to develop a generalized multi-feedstock and individual feedstock based models which can be used to determine the extent of delignification and cellulose conversion for any and specific biomass respectively with alkaline pretreatment and similar enzyme conditions as considered in the present study. Also, a kinetic model is developed and validated for sorghum for cellulosic conversion.

The influence of AKT isoforms on radiation sensitivity and DNA repair in colon cancer cell lines.

In response to ionizing radiation, several signaling cascades in the cell are activated to repair the DNA breaks, prevent apoptosis, and keep the cells proliferating. AKT is important for survival and proliferation and may also be an activating factor for DNA-PKcs and MRE11, which are essential proteins in the DNA repair process. AKT (PKB) is hyperactivated in several cancers and is associated with resistance to radiotherapy and chemotherapy. There are three AKT isoforms (AKT1, AKT2, and AKT3) with different expression patterns and functions in several cancer tumors. The role of AKT isoforms has been investigated in relation to radiation response and their effects on DNA repair proteins (DNA-PKcs and MRE11) in colon cancer cell lines. The knockout of AKT1 and/or AKT2 affected the radiation sensitivity, and a deficiency of both isoforms impaired the rejoining of radiation-induced DNA double strand breaks. Importantly, the active/phosphorylated forms of AKT and DNA-PKcs associate and exposure to ionizing radiation causes an increase in this interaction. Moreover, an increased expression of both DNA-PKcs and MRE11 was observed when AKT expression was ablated, yet only DNA-PKcs expression influenced AKT phosphorylation. Taken together, these results demonstrate a role for both AKT1 and AKT2 in radiotherapy response in colon cancer cells involving DNA repair capacity through the nonhomologous end joining pathway, thus suggesting that AKT in combination with DNA-PKcs inhibition may be used for radiotherapy sensitizing strategies in colon cancer.

Allelic drop-out may occur with a primer binding site polymorphism for the commonly used RFLP assay for the -1131T>C polymorphism of the Apolipoprotein AV gene.

Apolipoprotein AV (ApoAV) gene variant, -1131T>C, is associated with increased triglyceride concentrations in all ethnic groups studied. An MseI based RFLP analysis is the most commonly used method for genotyping this SNP. We genotyped a large cohort comprising 1185 Asian Indians and 173 UK Caucasians for -1131T>C using an ARMS-PCR based tetra-primer method. For quality control, we re-genotyped approximately 10% random samples from this cohort utilizing the MseI RFLP, which showed a 2.9% (3/102) genotyping error rate between the two methods. To investigate further, we sequenced the 900 bp region around the -1131T>C polymorphism in 25 Asian Indians and 15 UK Caucasians and found a number of polymorphisms including the -987C>T polymorphism. Further analysis of the -987C>T SNP showed a higher rare allele frequency of 0.23 in Asian Indians (n = 158) compared to 0.09 in the UK Caucasians (n = 157). This SNP is located 4 bp from the 3' end of the RFLP forward primer and is in weak linkage disequilibrium with -1131T>C variant (r2 = 0.084 and D' = 1). Repeated RFLP analysis of seven subjects heterozygous for -987C>T (seven times), showed discordant results with the sequence at -1131T>C SNP nearly one third (15/49) of the time. We conclude that presence of -987C>T polymorphism in the forward primer of the MseI RFLP assay may lead to allelic drop-out and generate unforeseen errors in genotyping the -1131T>C polymorphism. Our results also emphasise the need for careful quality control in all molecular genetic studies, particularly while transferring genotyping methods between various ethnic groups.