Reactions of purines-containing butenolides with L-cysteine or N-acetyl-L-cysteine as model biological nucleophiles: a potent mechanism-based inhibitor of ribonucleotide reductase caused apoptosis in breast carcinoma MCF7 cells

Thiols are the most reactive nucleophilic reagents among the biological models investigated. The reactivity of butenolides 1a-c, 2-4, and 6-8 toward L-cysteine, a model biological nucleophile, was studied spectrophotometrically. The rates of the reactions were measured and correlated with antitumour activity of these molecules. N-Acetylcysteine addition product 5, resulting from the treatment of butenolide 4 with glutathione precursor, N-acetyl-L-cysteine, was isolated. Unlike purine-containing gamma-(Z)-ethylidene-2,3-dimethoxybutenolides 1a-c, 4, 6, and 7, adduct 5 and butenolides 10-12 did not exhibit inhibitory activity against murine leukemias (L1210 and P388), breast carcinoma (MCF7), and human T-lymphoblasts (Molt4/C8 and CEM/0) cell lines. As such, the biological activity of purine-containing butenolides can be attributed to their adenine moiety as a recognition site as well as their reactivity towards the cysteine residues of functional proteins forming covalent bond via reverse Michael type addition. Adenine-containing phosphonothioanhydride derivative 8 was also synthesised. Its reaction with N-acetyl-L-cysteine produced N,S-diacetylcysteine and thiophosphonate 9. Compound 9 did not exhibit anticancer activity; yet its precursor 8 displayed the most pronounced inhibition on all the examined malignant tumour cell lines. In the presence of L-cysteine, cytotoxicity of 4 and 8 was decreased, whereas glutathione addition more influenced on the cytotoxicity of 8. It was found that adenine-containing phosphonothioanhydride 8 functions as a significant irreversible inactivator of the Escherichia coli ribonucleoside diphosphate reductase. After treatment of MCF7 cells with compound 8, fluorescence microscopy demonstrated the presence of nucleus shrinkage or segmentation. This apoptotic morphology, however, was not pronounced in the presence of glutathione or dithiotheritol.     

Methotrexate treatment provokes apoptosis of proliferating keratinocyte in psoriasis patients

Psoriasis is a chronic inflammatory skin disease characterized by hyper proliferation of keratinocytes. Recent data show that the epidermis thickening in psoriasis may be related to imbalance of homeostasis caused by abnormal apoptotic process. Maintenance of keratinocyte apoptotic process is very important in psoriasis. Methotrexate (MTX) has been used for many years to restore the normal skin in psoriasis condition. However, the exact mechanism of MTX in psoriasis condition is poorly understood. The aim of this study was to examine the role of MTX on keratinocyte apoptosis pathway in psoriasis patients. A total of 58 psoriasis vulgaris patients were recruited for this study. Nonlesional skin biopsies served as control. Skin biopsies of psoriatic patients were collected and analyzed for cytosolic, mitochondria and total cytochrome c by ELISA. Expression of caspase-9, NFκBp65, pAkt1 by western blot, real-time PCR and immunohistochemical analysis of c-FLIP protein was analyzed in nonlesional and lesional skin biopsies before (day 0) and after (at the end of 6 and 12 weeks) MTX treatment. After MTX treatment, a significant increase in cytochrome c was observed when compared with before MTX treatment in psoriasis patients (p < 0.001). Protein and gene expression of cleaved caspase-9 were significantly increased after MTX treatment, whereas the expression of Bcl-xL, c-FLIP, NFκBp65, pAkt1 significantly downregulated after MTX treatment. In conclusion, these results showed that intrinsic apoptotic pathway induced by MTX eventually adds the beneficial therapeutic role of MTX in psoriasis by controlling the acanthosis.     

Potential cytotoxic and apoptosis inducing agents: synthesis and evaluation of methoxy-substituted chalcones against human lung and cervical cancers

The role of methoxy group substitution in various positions in both the rings of chalcones on cytotoxicity profile was studied using various synthesized chalcones. The fluorine containing acetophenones when reacted with various methoxy-substituted benzaldehydes in the presence of 10 % sodium hydroxide solution gave the functionalized chalcones. All the synthesized chalcones were confirmed by spectral techniques like FTIR, ¹H NMR, ¹³C NMR, and HRMS studies. All the synthesized compounds were screened for their cytotoxicity against various cell lines. The promising compounds were analyzed for cell cycle analysis.     

Nature nominee quercetin's anti‐influenza combat strategy—Demonstrations and remonstrations

Nature's providences are rather the choicest remedies for human health and welfare. One such is quercetin, which is nature's nominee for cancer cure and recently demonstrated against influenza attack. Quercetin is highly recognized for its anticancer applications. This review emphasizes on yet another gift that this compound has to offer for mankind, which is none other than combating the deadly evasive influenza virus. The chemistry of this natural bioflavonoid and its derivatives and its modus operandi against influenza virus is consolidated into this review. The advancements and achievements made in the anti‐influenza clinical history are also documented. Further, the challenges facing the progress of this compound to emerge as a predominant anti‐influenza drug are discussed, and the future perspective for breaking its limitations through integration with nanoplatforms is envisioned.     

Proteome changes in autosomal recessive primary microcephaly

Background/aim

: Autosomal recessive primary microcephaly (MCPH) is a rare and genetically heterogeneous group of disorders characterized by intellectual disability and microcephaly at birth, classically without further organ involvement. MCPH3 is caused by biallelic variants in the cyclin-dependent kinase 5 regulatory subunit-associated protein 2 gene CDK5RAP2. In the corresponding Cdk5rap2 mutant or Hertwig's anemia mouse model, congenital microcephaly as well as defects in the hematopoietic system, germ cells and eyes have been reported. The reduction in brain volume, particularly affecting gray matter, has been attributed mainly to disturbances in the proliferation and survival of early neuronal progenitors. In addition, defects in dendritic development and synaptogenesis exist that affect the excitation-inhibition balance. Here, we studied proteomic changes in cerebral cortices of Cdk5rap2 mutant mice.

Material and methods

: We used large-gel two-dimensional gel (2-DE) electrophoresis to separate cortical proteins. 2-DE gels were visualized by a trained observer on a light box. Spot changes were considered with respect to presence/absence, quantitative variation and altered mobility.

Result

: We identified a reduction in more than 30 proteins that play a role in processes such as cell cytoskeleton dynamics, cell cycle progression, ciliary functions and apoptosis. These proteome changes in the MCPH3 model can be associated with various functional and morphological alterations of the developing brain.

Conclusion

: Our results shed light on potential protein candidates for the disease-associated phenotype reported in MCPH3.     

Quantitative Detection of Cirrhosis: Towards the Development of Computer-Assisted Detection Method

There are distinct morphologic features of cirrhosis on CT examinations; however, such impressions may be subtle or subjective. The purpose of this study is to build a computer-aided diagnosis (CAD) method to help radiologists with this diagnosis. One hundred sixty-seven abdominal CT examinations were randomly divided into training (n = 88) and validation (n = 79) sets. Livers were analyzed for morphological markers of cirrhosis and logistic regression models were created. Using the area under curve (AUC) for model performance, the best model had 0.89 for the training set and 0.85 for the validation set. For radiology reports, sensitivity of reporting cirrhosis was 0.45 and specificity 0.99. Using the predictive model adjunctively, radiologists’ sensitivity increased to 0.63 and specificity slightly decreased to 0.97. This study demonstrates that quantifying morphological features in livers may be utilized for diagnosing cirrhosis and for developing a CAD method for it.     

Synthesis of Methoxy‐substituted Chalcones and in vitro Evaluation of their Anticancer Potential

Methoxy‐substituted chalcones, 3 were obtained using simple, efficient method from 2‐naphtylethanone, 1 and aromatic aldehydes, 2. The in vitro cytotoxicity activities of the chalcones against a panel of three human cancer cell lines were explored. The tested compounds were found to possess significant cytotoxic activity. The DNA strand break and damage was quantified through alkaline comet assay, flow cytometric analysis, and chromatin condensation studies, which revealed the apoptotic nature of the compounds. Compound 3c, (3‐(3,4,5‐trimethoxyphenyl)‐1‐(2‐naphthyl) prop‐2‐en‐1‐one) showed highest cytotoxicity of 0.019 μm against HeLa, 0.020 μm against HCT15 and 0.022 μm against A549. Compound 3e, (3‐(3,5‐dimethoxyphenyl)‐1‐(2‐naphthyl) prop‐2‐en‐1‐one) showed better IC50 values against all the three cell lines employed for the study.     

Supported and unsupported claims in medicinal drug advertisements in Indian medical journals

The study assessed 292 supported and unsupported claims in 102 medicinal drug advertisements across 15 Indian medical journals published in 2009. WHO ethical criteria for medicinal drug promotion were applied. None of the advertisements satisfied all the WHO criteria. Safe prescribing information on major adverse drug reactions, contraindications and warnings was provided in only 19 advertisements. Of 292 drug claims, only 80 (27%) were supported with reference(s), of which only 7 (9%) claims were unambiguous, or well substantiated with references. 14 references quoted did not substantiate the claim and 15 constituted weak scientific evidence. Superlatives like "tested" "trusted" "guarantees success" and "matchless safety" were used without evidence to substantiate such claims. Stronger enforcement mechanisms are necessary to ensure reliable drug information in pharmaceutical advertisements.