Toxicity and Anti-Oxidation Capacity of The Extracts from Caulerpa lentillifera

Caulerpa lentillifera (sea grape) has been widely used in pharmaceutical industry and health-care products in Thailand. In this study, we attempted to evaluate the toxicity and antioxidant capacity of sea grape extracts in five fractions (ethanol- CLET, hexane- CLHE, ethyl acetate- CLEA, butanol-CLBU, and aqueous-CLAQ). The extracts were evaluated for cytotoxicity by MTT and LDH assays on four cell lines, fibroblast (L929), macrophages (RAW 264.7), hepatocytes (FL83B), and keratinocytes (HaCaT). Genotoxicity was tested by comet assay and micronucleus assay on human lymphoblast cells (TK6). The antioxidant capacity was measured by DPPH and ABTS scavenging assays. Our results demonstrated low cytotoxicity and genotoxicity of CLET, CLBU and CLAQ. When tested by DPPH and ABTS assays, CLET, CLEA, and CLHE showed high antioxidant activity. In conclusion, CLET, CLBU, and CLAQ demonstrated no toxic effects, and CLET, CLEA, and CLHE exhibited high antioxidant capacity. Therefore, our results indicated that CLET, CLEA, and CLHE could be consumed safely at doses lower than 500 and 200 μg/ml for CLHE and CLEA, respectively. Keywords: Anti-oxidation, Caulerpa lentillifera, Cytotoxicity, Genotoxicity

Potential depression and antidepressant-response biomarkers in human lymphoblast cell lines from treatment-responsive and treatment-resistant subjects: roles of SSRIs and omega-3 polyunsaturated fatty acids

While several therapeutic strategies exist for depression, most antidepressant drugs require several weeks before reaching full biochemical efficacy and remission is not entirely achieved in many patients. Therefore, biomarkers for depression and drug-response would help tailor treatment strategies. This study made use of banked human lymphoblast cell lines (LCLs) from normal and depressed subjects; the latter divided into remitters and non-remitters. Due to the fact that previous studies have shown effects on growth factors, cytokines and elements of the cAMP generating system as potential biomarkers for depression and antidepressant action, these were examined in LCLs. Initial gene and protein expression profiles for signaling cascades related to neuroendocrine and inflammatory functions differ among the three groups. Growth factor genes, including VEGFA and BDNF were significantly down-regulated in cells from depressed subjects. In addition, omega-3 polyunsaturated fatty acids (n-3 PUFAs) have been reported to act as both antidepressants and anti-inflammatories, but the mechanisms for these effects are not established. Here we showed that n-3 PUFAs and escitalopram (selective serotonin reuptake inhibitors, SSRIs) treatment increased adenylyl cyclase (AC) and BDNF gene expression in LCLs. These data are consistent with clinical observations showing that n-3 PUFA and SSRI have antidepressant affects, which may be additive. Contrary to observations made in neuronal and glial cells, n-3 PUFA treatment attenuated cAMP accumulation in LCLs. However, while lymphoblasts show paradoxical responses to neurons and glia, patient-derived lymphoblasts appear to carry potential depression biomarkers making them an important tool for studying precision medicine in depressive patients. Furthermore, these data validate usefulness of n-3 PUFAs in treatment for depression.

A COMPREHENSION INTO TARGET BINDING AND SPATIAL FINGERPRINTS OF NOSCAPINOID ANALOGUES AS INHIBITORS OF TUBULIN

Aim: The present research aims to insight into target binding and mapping of spatial fingerprints of noscapinoids as inhibitors of tubulin. Background: Owing to its potential to interfere in microtubule dynamics in mitotic phase of cell cycle and selectively inducing apoptosis in cancer cells without affecting normal cells, noscapine and its synthetic analogues have been investigated by other research groups in different cell lines for their capability to use as anti-cancer agents. Objective: The present study is focused on investigation of mode of binding of noscapinoids with tubulin, prediction of target binding affinities and mapping of their spatial fingerprints (shape and electrostatic). Methods: Molecular docking assisted alignment based 3D-QSAR technique self organizing molecular field analysis (SOMFA) was used on a dataset (43 molecules) having inhibitory activity (IC50 = 1.2-250 µM) against human lymphoblast (CEM) cell line. Results: Key amino acid residues of target tubulin were mapped for the binding of most potent noscapine analogue (Compound 11) and compared with noscapine. Spatial fingerprints of noscapinoids for favorable tubulin inhibitory activity were generated as an outcome of 3D-QSAR analysis. Conclusion: The generated spatial fingerprints of noscapinoids would be used for further pharmacophoric amendments of noscapine analogues to design and develop novel potent noscapine based anti-cancer agents.The present molecular modeling study will be helpful to medicinal chemist in understanding the structural features of noscapinoids for further designing and synthesis of target specific safer inhibitors of tubulin that may enter to drug development pipeline.

Quantifying the RNA cap epitranscriptome reveals novel caps in cellular and viral RNA

Chemical modification of transcripts with 5′ caps occurs in all organisms. Here, we report a systems-level mass spectrometry-based technique, CapQuant, for quantitative analysis of an organism's cap epitranscriptome. The method was piloted with 21 canonical caps—m7GpppN, m7GpppNm, GpppN, GpppNm, and m2,2,7GpppG—and 5 ‘metabolite’ caps—NAD, FAD, UDP-Glc, UDP-GlcNAc, and dpCoA. Applying CapQuant to RNA from purified dengue virus, Escherichia coli, yeast, mouse tissues, and human cells, we discovered new cap structures in humans and mice (FAD, UDP-Glc, UDP-GlcNAc, and m7Gpppm6A), cell- and tissue-specific variations in cap methylation, and high proportions of caps lacking 2′-O-methylation (m7Gpppm6A in mammals, m7GpppA in dengue virus). While substantial Dimroth-induced loss of m1A and m1Am arose with specific RNA processing conditions, human lymphoblast cells showed no detectable m1A or m1Am in caps. CapQuant accurately captured the preference for purine nucleotides at eukaryotic transcription start sites and the correlation between metabolite levels and metabolite caps.

Treatment of human cells with 5-aza-dC induces formation of PARP1-DNA covalent adducts at genomic regions targeted by DNMT1

ABSTRACTThe nucleoside analog 5-aza-2’-deoxycytidine (5-aza-dC) is used to treat some hematopoietic malignancies. The mechanism of cell killing depends upon DNMT1, but is otherwise not clearly defined. Here we show that PARP1 forms covalent DNA adducts in human lymphoblast or fibroblasts treated with 5-aza-dC. Some adducts recovered from 5-aza-dC-treated cells have undergone cleavage by apoptotic caspases 3/7. Mapping of PARP1-DNA adducts, by a new method, “Adduct-Seq”, demonstrates adduct enrichment at CpG-dense genomic locations that are targets of maintenance methylation by DNMT1. Covalent protein-DNA adducts can arrest replication and induce apoptosis, and these results raise the possibility that induction of PARP1-DNA adducts may contribute to cell killing in response to treatment with 5-aza-dC.