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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a ruthless killer of the human population and highly transmissible, has become a big threat to public health by spreading one of the most infectious coronavirus diseases (COVID-19) Vaccine production is of paramount importance at present, albeit it is a gradual and time taking process Since the predicament demand is immediate prevention, we hypothesized the utility of IgG2a LA5 and IgA antibodies developed inside the body after vaccination to assess its protective effects as non-specific immunity against SARS-CoV-2 Identifying the vaccine for repurposing, we considered the C-terminal domain of spike protein (S1-CTD) and envelope (E) protein for molecular interactions with aforesaid antibodies using computational and Bioinformatics tools in order to elucidate its practicality and applicability Our in silico findings exhibited the involvement of S1-CTD and E-protein hotspot residues as key players in molecular interaction with IgG2a LA5 and IgA and exhibited better binding efficiency (higher negative ∆G and lower Kd values) in comparison to their cognate host receptors (ACE2 and MPP5) Detailed hotspot residue analysis of S1-CTD and E-protein with IgG2a LA5 and IgA indicates that the existing vaccine could be used as a preventive measure against SARS-CoV-2 © 2020 by the authors

It is an ongoing task to keep exploring and applying the best available technology to alleviate the pain and sufferings of the cancer patients. Since the discovery of robotic surgery, da Vinci surgical systems have played a special and significant role in cancer surgeries worldwide, however, surgeons are still skeptical with the clinical and oncological outcomes which are almost comparable to the laparoscopic approach in several cancers. Many meta-analyses using mostly retrospective studies indicated significant advantage of robotic surgery over laparoscopic or open surgery approaches for various cancers, however, scarcity of technically sound robot savvy surgeons and quality multicentered, multinational, coordinated, random clinical trials had not done justice to the positives of robotic surgery which were quite often suppressed by the negative factors like operative cost and oncological outcomes. Nevertheless, robotic surgery approach has been clinically accepted for hysterectomy and prostatectomy. This overview briefly discusses the comparative approaches (open, laparoscopic, robotic assisted) and their clinical outcomes in the surgery of various cancers.

The research aims to identify the inhibitory potential of natural dietary phytochemicals against non-insulinotropic target protein alpha-glucosidase and its possible implications to diabetes mellitus type 2.A data set of sixteen plant-derived dietary molecules viz., 4,5-dimethyl-3-hydroxy-2(5H)-furanone, apigenin, bromelain, caffeic acid, cholecalciferol, dihydrokaempferol 7-o-glucopyranoside, galactomannan, genkwanin, isoimperatorin, luteolin, luteolin 7-o-glucoside, neohesperidin, oleanoic acid, pelargonidin-3-rutinoside, quercetin, and quinic acid were taken to accomplish molecular docking succeeded by their comparison with known inhibitors including acarbose, miglitol, voglibose, emiglitate, and 1-deoxynojirimycin. Among all phyto-compounds, bromelain (ΔG: -9.54 kcal/mol), cholecalciferol (-8.47 kcal/mol), luteolin (-9.02 kcal/mol), and neohesperidin (-8.53 kcal/mol) demonstrated better binding interactions with alpha-glucosidase in comparison to the best-known inhibitor, acarbose (ΔG: -7.93 kcal/mol). Molecular dynamics simulation of 10 ns duration, CYP450 site of metabolism identification, and prediction of activity spectra for substances depicted the bromelain as the most stable inhibitor compared to luteolin and acarbose. Findings of molecular interactions, molecular dynamics study, metabolism, and biological activity prediction proved bromelain as a potential alpha-glucosidase inhibitor. Thus, bromelain might be helpful as an insulin-independent therapeutic molecule towards controlling and managing diabetes mellitus type 2.

Neurological diseases are prevalent in the populations from the developed nations including Europe and North America, while South America also shows a high prevalence of Parkinson's disease (PD). Although. PD is among the most prevalent neurodegenerative conditions, its cause remains largely unknown. Changing age structure and marked demographic shifts, with progressively larger percentage of their populations entering old age, has been seen in many countries. Females have been found to have a higher life expectancy and longevity than males at any age. We compiled the freely available data on COVID-19, and statistics on life expectancy, and ageing population from the United Nations. The XY-scatter plots with regression analysis were used to assess the correlation between case fatality rate (CFR)/deaths and life expectancy of various countries. We infer that the SARS-00V-2 mediated infections mostly affected the elderly people of age 60+years, who accounted for approximately 50% (20-88.45%) of the total deaths by COVID-19. However, females were found to be 1.66 times less prone to COVID-19-induced deaths compared to the males. The X Y-scatter plot showed no correlation between life expectancy and CFR or deaths due to COVID-19. Similar patterns of CFR/deaths by COVID-19 and PD prevalence were also observed in Europe and America. All the factual data including increased susceptibility of males to COVID-19 and PD, along with relatively less life expectancy than females, indicate that the world may virtually be heading towards a predominantly female older population. However, caution may be exercised in interpreting the results of this preliminary study that may be affected by incorrect or biased reporting on COVID-19 data, regional variations in the infectivity by new mutant strains of SARC-COV-2, and the prevalence and epidemiology of PD and COVID-19 might also affect the associated risk factors for PD in certain population.

Breast cancer is the leading cause of death among women worldwide. It is a multi-factorial disease caused by genetic and environmental factors. Vitamin D has been hypothesized to lower the risk of breast cancer via the nuclear vitamin D receptor (VDR). Genetic variants of these vitamin D metabolizing genes may alter the bioavailability of vitamin D, and hence modulate the risk of breast cancer. Materials and Methods: The distribution of Fok1 VDR gene (rs2228570) polymorphism and its association with breast cancer was analysed in a case–control study based on 125 breast cancer patients and 125 healthy females from North Indian population, using PCR-RFLP. An In silico exploration of the probable mechanism of increased risk of breast cancer was performed to investigate the role of single nucleotide polymorphisms (SNPs) in cancer susceptibility. Results: The Fok1 ff genotype was significantly associated with an increased risk of breast cancer (p=0.001; χ2=13.09; OR=16.909; %95 CI=2.20 - 130.11). In silico analysis indicated that SNPs may lead to a loss in affinity of VDR to calcitriol, and may also cause the impairment of normal interaction of liganded VDR with its heterodimeric partner, the retinoid X receptor (RXR), at protein level, thereby affecting target gene transcription. Conclusion: Breast cancer risk and pathogenesis in females can be influenced by SNPs. SNPs in VDR may cause alterations in the major molecular actions of VDR, namely ligand binding, heterodimerization and transactivation. VDRE binding and co-activator recruitment by VDR appear to be functionally inseparable events that affect vitamin D-elicited gene transcription. This indicates that breast cancer risk and pathogenesis in females may be influenced by SNPs.

To study the biochemical adaptive responses of the blue green algae Nostoc muscorum to the salinity- induced stress they were exposed to various concentrations (5, 10, 15, 20 or 200 mM) of sodium chloride (NaCl). A dose-dependent inhibition of total protein content showed an adverse effect of NaCl on the growth of N. muscorum. Four-day treatment of NaCl (5–20 mM) progressively increased the content of the total peroxide with subsequent increase of the superoxide dismutase (SOD) activity, proline and total phenol content only up to 10 mM NaCl. Higher concentrations of NaCl caused significant decrease in both the enzymatic and non-enzymatic antioxidants. Induction of two polypeptides of ~29.10 and 40.15 kD as well as upregulation of many polypeptides as compared to control indicates the induction of SOD and dehydrin-like proteins, which supports the theory of adaptation against the salt stress. Furthermore, adaptation of N. muscorum to lower concentrations (5–20 mM) of NaCl was also confirmed by no fragmentation of DNA while DNA fragmentation indicating programmed cell death (PCD) could only be seen at 200 mM NaCl for 12 hours. We hypothesized that proline may confer a positive role to combat salinity stress and the same was confirmed by treatment of the test blue green algae with exogenous proline (1 and 10 μM). The results exhibited 16% reduction in the level of total peroxides, which is a well known oxidative stress marker in the 10 μM proline-treated NaCl group as compared to direct exposure to NaCl.

Survivin (IAP proteins) remains an important target for anticancer drug development as it is reported to be over-expressed in tumor cells to enhance resistance to apoptotic stimuli. The study focuses on virtual screening of marine compounds inhibiting survivin, a multifunctional protein, using a computational approach. Structures of compounds were prepared using ChemDraw Ultra 10. Software and converted into its 3D PDB structure and its energy was minimized using Discovery Studio client 2.5. The target protein, survivin was retrieved from RCSB PDB. Lipinski's rule and ADMET toxicity profiling was carried out on marine compounds and the filtered compounds were further promoted for molecular docking analysis and interaction studies using AutoDock Tools 4.0. Molecular docking results revealed that analog (AP 4) of Aplysin, showed very promising inhibitory potential against survivin with a binding energy of -8.75 kcal/mol and Ki 388.28 nM as compared to its known inhibitor, Celecoxib having binding energy of -6.65 kcal/mol and Ki 13.43 μM. AP 4. The analog depicted similarity in pattern when compared to standard. The result proposes AP 4, is an effective molecule exhibiting prominent potential to inhibit survivin and thus promoting apoptosis in tumor cells.

In the proposed work, we have explicated the mechanism of dibenzo[a,l]pyrene (DBP) and benzo[a]pyrene (BP) modulated cell proliferation by assessing the plausible binding with CASPASES, BAX, Bcl-2, MDM2, p53, p21, p16, CylinD1-CDK4 complex, CylinE1-CDK2 complex, H-Ras, K-Ras, BRCA1, and BRCA2 through exploiting the inherent potential of AutoDock Tools 4.0. In silico findings revealed that potent carcinogenic metabolites of DBP (e.g., (-)-anti-DBPDE and (+)-syn-DBPDE) and BP (e.g., (+)-anti-BPDE) exhibited better binding interactions to Caspase-9 than Caspase-8 and Caspase-3. Feeble interactions of BAX and Bcl-2 with diol-epoxides of both PAHs were observed. Diol-epoxides of DBP and BP were found to bind to p53 with tighter interaction than MDM2 and p53-MDM2 complex. The p16 and Cyclin-CDK complexes were best docked to aforesaid metabolites as compared to p21. Moreover, stronger interactions of BRCA1 and BRCA2 with DBP and feeble interactions of BRCA1 and BRCA2 with BP were observed from docking results. Furthermore, stronger interactions of both DBP and BP with the H-Ras and K-Ras oncoproteins were found, while only DBP interacted relatively strongly with the BRCA1 and BRCA2, which were suggesting more carcinogenic nature of DBP than BP, a well-known observation in the wet lab. Besides giving structural insight into the mechanism of DBP and BP-mediated cell proliferation, these in silico findings may be helpful to understand the mechanistic nature of environmental carcinogens and their cellular targets.

High-throughput virtual screening (HTVS) methods have played a cardinal role in the development of therapeutically important natural compounds. HTVS allows scientists to rapidly perform millions of chemical, biological, pharmacological, or toxicological tests on natural compounds. These screening procedures enable the researchers to rapidly identify active natural compounds that can modulate a particular biomolecular mechanism or pathway. The screening results help to study the interaction/role of a bioactive compound in a particular biochemical process at cellular level and provide preliminary ideas for drug design development. These methods are generally classified as either ligand based or structure based. Structure-based methods are in principle analogous to high-throughput screening where the information of both biomolecular target and ligand structure is essential. Structure-based approaches include docking, simulations, dynamics, and ligand design methods. Ligand-based methods use only ligand information for predicting activity depending on its similarity/dissimilarity to previously known active ligands. Here, we discuss the widely used techniques, tools, and databases for virtual screening of natural compounds. Finally, computational methods for absorption, distribution, metabolism, excretion - and toxicity (ADMET) prediction are discussed.

The present study was accomplished to examine and compare the effect of specific antioxidant-rich oils on hyperglycemia, dyslipidemia, renal function markers and oxidative renal damage in diabetic rats for four weeks. Papaya (P), olive (O), fenugreek (Fe), bitter gourd (B) and fish (Fi) oils were used for this purpose. Streptozotocin (STZ) was injected intraperitoneally in a single dose to induce diabetes. All oils were given orally at a dose of 3g/kg for four weeks in respective group after induction of diabetes. After treatment with oils, blood was collected, and their kidneys were stored. The level of fasting blood glucose (FBG), glycated hemoglobin (HbA1c), total cholesterol (TC), triglycerides (TG), low-density lipoprotein-cholesterol (LDL-C) and very low-density lipoprotein-cholesterol (VLDL-C) increased while amylase and high-density lipoprotein cholesterol (HDL-C) level decreased in the diabetic rats. These changes were augmented by fenugreek, bitter gourd and olive oils treatment. Diabetic rats showed elevated renal function markers in serum, including, serum creatinine (Scr), blood urea nitrogen (BUN) and alkaline phosphatase (ALP), which were restrained significantly by fenugreek and bitter gourd oil treatment. Moreover, fenugreek and bitter gourd oils treatment significantly modulated the level of thiobarbituric reactive substances (TBARS), malonaldehyde (MDA) and catalase (CAT) in the kidney of diabetic rats. The histopathological examination also showed the protective effect of these oils. The study suggests that vegetable oils are effective in reducing hyperglycemia, dyslipidemia and renal damage related to the side effects of diabetes. Thus they may have therapeutic value for preventing diabetes side effects and may be included in oil diet treatment synergically. Thus, our data suggest that oils as potent antidiabetic agent and beneficial in the control of diabetes-related abnormalities such as hyperglycemia, dyslipidemia and renal damage of STZ induced rat model of type 2 diabetes. Our study also supports the suggestion that synergistic possibilities exist concerning the use of these oils in the treatment of diabetes mellitus.

Exposure to exogenous and endogenous chemicals and subsequent cellular and molecular changes has been linked to enhanced cell proliferation and restricted apoptosis phenomenon. Though in the past decades numerous anticancer drugs inducing programmed cell death in cancer cells by targeting specific apoptotic markers have reached the market, they have been allied with unwanted side effects, ranging from mild to severe toxicity. With further understanding on the functional mechanism of p53 and MDM2 in apoptosis and in our continuous search for new and potent multi-target anticancer lead compounds, we have carried out molecular docking and inhibition studies of the selected aglycones along with selected anticancer leads, against the specific apoptotic and cell cycle markers using AutoDock Tools 4.0 and other computational softwares. The docking results have been analyzed in terms of binding energies (kcal/mol) and inhibition constant (µM). The study clearly proposes our aglycones [solanidine (Solanid-5-en-3β-ol), solasodine (Solasod-5-en-3β-ol), and tomatidine (5α-Tomatidan-3β-ol)] induce apoptosis by inhibiting the p53-MDM2 complex, p21Waf1/Cip1, and Bcl-2 proteins, which were even found comparable with the anticancer drugs nutlin and/or halofuginone. The work further emphasizes that the individual molecular targets such as BAX and Bcl-2 may result in misleading data at any level; however, ratio of responses to BAX and Bcl-2 shall be considered for better clue about a compound to be pro- or anti-apoptotic.

Periodontitis is a chronic, non-reversible inflammatory disease of the oral cavity leading to destruction of periodontal tissues. Thus, the estimation of bacterial metabolite, tissue damage and secretory metabolites of the triggered inflammatory cells likely to yield results. It may be of value for understanding the pathophysiology of the disease by metabolic profiling of saliva samples using high-resolution NMR spectroscopy. The study will evaluate the difference in salivary metabolites in healthy and periodontal condition along with fetching of possible biomarkers in case of chronic periodontitis. 1H- NMR spectroscopy has been employed in 114 saliva samples in search of distinctive differences and spectral data were further subjected to multivariate analysis. One-hundred metabolites were characterised and assigned in the 1H NMR spectra of saliva. The statistical analysis of control (Healthy subjects) and diseased (Periodontal subjects) using PLS-DA model resulted in R2 of 0.84 and Q2 of 0.79. There was an elevation in the concentration of statistically discriminant metabolites. The twenty newly identified metabolites in saliva indicates bacterial population shift along with change in homeostasis. These disturbs the biofilm, a real protector against any possible bio-damage on tooth surface. These newly identified metabolites could define better geographically diversified periodontal condition. Analysis clearly differentiates healthy subjects from the diseased ones. Few newly identified metabolites along with the pool of metabolites may serve as biomarkers for distinguishing the severity and complexity of periodontitis.

Background The present study clarifies the molecular interactions of human BACE1 with novel natural ligands and also with the well-known ligand 2, 2, 4-trihydroxychalcone and Galangin for comparison. Objective The study of enzyme- ligands interaction is interesting, thus description of ligands binding to the active site of target molecule could be beneficial for better understanding the mechanism of the ligand on the target molecule. Methods Lipinski rule of five and docking study were performed between ligands and enzyme using 'Autodock4.2'. Results It was found that hydrogen bond interactions play a significant role in the accurate positioning of ligands within the 'active site' of BACE1 to permit docking. Such information may aid to propose the BACE1 -inhibitors and is estimated to aid in the safe medical use of ligands. Selected ligands of BACE1 also inhibit the aggregated amyloid beta peptide. The aggregation of amyloid peptides Aβ1-42 may be responsible for AD. Conclusion Scope lies in the determination of the 3-dimensional structure of BACE1 and ligands complex by X-ray crystallography to certify the explained data. To validate the enzyme -ligands results, we considered 2, 2, 4-trihydroxychalconeas and Galangin as a positive control. Moreover, the current study verifies that ligands are more capable inhibitors of human BACE1 compared to positive control with reference to ΔG values.

Malignant tumors are the leading cause of death in humans. Due to the tedious efforts and investigations made in the field of marine drug discovery, there is now a scientific bridge between marine and pharmaceutical sciences. However, currently only few marine drugs have been lined towards anticancer direction yet many more to are be established in future as well.This review gives an overview of present status of marine natural products MNPs both at the level of research and clinical stages. The authors haved summarized the detail information of diverse marine organisms that were reportedto be active or potentially active in cancer treatment in the last two decades. Interstingly, marine organisms are abundant producer of plenty of structurally incomparable bioactive metabolites that have unusual mode of actions and diverse biosynthetic pathways.This review summarizes the associated anticancer properties of different classes of marine natural compounds based on their structural diversity, biological activity, and the molecular mechanisms of action. Emphasis has also be given to recent advances in clinical development of marine agents used in clinical trials.The present review is summarising the various sources of marine chemicals and their exploration of anticancerous potential. There is justified hope for the discovery and development of new anticancer agents from the marine environment.

4-hydroxy-tetrahydrodipicolinate synthase (DHDPS) is an important enzyme needed for the biosynthesis of lysine and many more key metabolites in Mycobacterium tuberculosis (Mtb). Inhibition of DHDPS is supposed to a promising therapeutic target due to its specific role in sporulation, cross-linking of the peptidiglycan polymers and biosynthesis of amino acids. In this work, a known inhibitor-based similarity search was carried out against a natural products database (Super Natural II) towards identification of more potent phyto-inhibitors. Molecular interaction studies were accomplished using three different tools to understand and establish the participation of active site residues as the key players in stabilizing the binding mode of ligands and target protein. The best phyto-compound deduced on the basis of binding affinity was further used as a template to make similarity scan across the PubChem Compound database (score > = 80 %) to get more divesred leads. In this search 5098 hits were obtained that further reduced to 262 after drug-likeness filtration. These phytochemicallike compounds were docked at the active site of DHDPS.Then, those hits selected from docking analysis that showing stronger binding and forming maximum H-bonds with the active site residues (Thr54, Thr55, Tyr143, Arg148 and Lys171). Finally, we predicted one phytochemical compound (SN00003544), two PubChem-compounds (CID41032023, CID54025334) akin to phytochemical molecule showing better interactions in comaprison of known inhibitors of target protein.These findings might be further useful to gain the structural insight into the designing of novel leads against DapA family.

Due to high level of blood sugar, some glucose molecules are attached to the normal hemoglobin which is known as glycated hemoglobin (HbA1c). HbA1c indicates the average blood glucose levels over the past 6 to 8 weeks. Therefore, it has been recommended as a screening tool for the detection and monitoring of diabetes mellitus. HbA1c at high levels are associated with various metabolic disorder and other disease. In the present review, we summarized risk factors associated with increased level of HbA1c and its clinical significance.

The 2,4,5-triaryl imidazole derivatives (API) were designed, screened and characterized kinetically & thermodynamically against Pepsin and their activity was also tested on the in silico platform. The docking studies of API with Pepsin show that these are novel and unique inhibitors of Aspartic protease. Drug like properties of these compounds were validated in silico based on Lipinski's rule of Five by calculating ClogP, LogS, H-bond acceptors, H-Bond donors, rotational bonds, PSA, PB and BBB values. The Et/Ki and Et/Km values of API show that they follow the Michaelis-Menten kinetics. The binding of inhibitors with proteases was explained by using Van't Hoff plot and thermodynamic parameters viz. free energy (ΔG), Entropy (ΔS) and Enthalpy (ΔH). The Van't Hoff analysis showed that the value of Ki decreases with increase in temperature and the binding of the inhibitor are entropically driven. API act as new potent aspartic protease inhibitors with Ki, for Pepsin, ranges from 3.7 µM to 16.7 µM. Strong hydrophobic groups at C-4 & C-5 position in API favor binding of inhibitors with Pepsin. Experiments also showed that among C-2 aryl substituted imidazole, a 4-substitution on aryl ring is preferred and less polar substituent makes the molecule more active whereas polar substituents at 2-position on C-2 aryl ring makes the molecule less active. The docking studies of API with Pepsin further intensify and validate our results.

To establish in silico model to predict the structural insight into the metabolic bioactivation pathway of xenobiotics, we considered two specific and one non-specific mammary procarcinogen [e.g., dibenzo[a,l]pyrene (DBP), 7,12-dimethylbenz[a]anthracene (DMBA), and benzo[a]pyrene (BP)]. The CYP1A1, 1B1, 2C9, 1A2 and 2B6 reported in wet-lab studies to actively metabolize DBP also showed strong binding energies (kcal/mol) of −11.50, −10.67, −10.37, −9.76 and −9.72, respectively, with inhibition constants ranging between 0.01 and 0.08 µM. The CYP3A4 depicted minimum binding energy (−9.51 kcal/mol) which is in agreement with the wet-lab reports. Further, relatively better affinity of CYP1A1 and CYP1B1 with the dibenzo[a,l]pyrene-11,12-diol (DBPD) might be indicative of their involvement in carcinogenicity of parent compound. Like DBP, BP (−10.13 kcal/mol, Ki: 0.04 µM) and BP-diols (BPD) (−9.01 kcal/mol, Ki: 0.25 µM) observed plausible binding with CYP1A1 supporting to the reported data that emphasize the major contribution of CYP1A1 in the activation of similar procarcinogens and mutagens. Likewise, in silico results further highlighted the CYP1A1 as key player in bioactivation of DMBA to its carcinogenic metabolites. In case of PhIP metabolism, strong binding interaction predicted with CYP1A1 (−9.63 kcal/mol) rather than CYP1A2 (−8.84 kcal/mol). Dissimilarity in the binding affinity of PhIP might be due to its basic scaffold. Further, molecular dynamics (MD) simulation of 10 ns has been revealed that docked complexes of CYP1A1 with DBP, DMBA and BP are comparatively more stable than the complex of PhIP. Moreover, the current findings might be valuable as reference model in prediction and elucidation of the approximate metabolic pathway of xenobiotics.

Currently used hypolipidemic drugs, Fluvastatin and Atorvastatin, act via inhibiting the rate-limiting enzyme 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase of the mevalonate pathway. The associated severe side-effects of these statins led us to explore the therapeutic potentials of naturally occurring Tocomin (mixture of dietary α-, β-, γ- and δ-tocotrienols). Tocomin (10 mg) was orally administered daily for 10 days before and 12 h after bacterial lipopolysaccharide (200 μg) or 24 h after zymosan (20 mg) or turpentine (0.5 mL) to Syrian hamsters. The data showed that Tocomin significantly reduced the levels of plasma and lipoprotein lipids, cholesterol, apoB, small dense (sd)-LDL as well as LDL in the hyperlipidemia-induced hamsters. Further, the mechanism of action of α-, β-, γ- and δ-tocotrienols was validated by docking studies with HMG-CoA reductase enzyme using the Molegro Virtual Docker. The inhibition of HMG-CoA reductase predicted in terms of MolDockScore and interaction energy suggest the comparative potential in the descending order: Atorvastatin > Fluvastatin ~ δ > γ > β > α. The results favor the daily intake of naturally occurring tocotrienols as dietary supplement in the prevention and treatment of infection/inflammation induced dyslipidemia compared with the hypolipidemic drugs. Copyright © 2011 John Wiley & Sons, Ltd.

Receptor tyrosine kinases (RTKs) are crucial targets in the pathway of angiogenesis and the currently used antiangiogenic drugs have limited efficiency with associated toxicity. In our continuous search for new and potent multitarget anti-angiogenic lead compounds, we have conducted in-silico interaction and inhibition studies of the selected aglycones of steroidal glycoalkaloids (GAs) and selected anti-angiogenic drugs, against the EGFR, VEGFR-1, VEGFR-2 using the AutoDock Tools 4.0 and other online bioinformatics softwares. The docking results have been interpreted in terms of binding energies (kcal/mol) and inhibition constant ( M). In our study, aglycones [solanidine (solanid-5-en-3 -ol), solasodine (Solasod-5-en-3 -ol) and tomatidine (5 -Tomatidan-3 -ol)] gave promising and comparable results with the antiangiogenic drugs (Gefitinib, Lapatinib, Axitinib and Motasenib). All the test aglycones expressed significant inhibition against RTKs under study, but tomatidine emerged as a most potent multi-target inhibitor of RTKs. The inhibition constant of tomatidine was observed almost 2-folds less compared to Gefitinib targeting against EGFR and 5-folds less to Axitinib, the standard drug against VEGFR-2. Moreover, these aglycones fulfilled the drug likeliness properties, when analyzed by Lipinski’s Rule of Five. In addition to this, the in-silico toxicity studies of aglycones remarkably showed no mutagenecity and tumorigenecity compared to the standard drugs. Our results for the first time report that these novel aglycones of GAs may be significant lead compounds in the development of new and effective multi-target antiangiogenic drugs with the least or no toxicity. In addition, the wet lab experiments are underway to support these in-silico

Dimethyl 4,4' -(O-phenylene)bis(3-thioallophanate), commonly known as methyl thiophanate (MT), is a systemic fungicide and suspected carcinogen to humans. In this study, the oxidative potential of this category-III acute toxicant has been ascertained based on its capacity of inducing reactive oxygen species (ROS) and promutagenic 8-oxo-7,8-dihydro-2' -deoxyguanosine (8-oxodG) adducts in DNA. The discernible MT dose-dependent reduction in fluorescence intensity of a cationic dye rhodamine (Rh-123) in human lymphocytes and increased fluorescence intensity of 2',7'-Dichlorodihydro fluorescein diacetate (DCFH-DA) treated cells signifies decreased mitochondrial membrane potential (Delta Psi m) due to intracellular ROS generation. The (32)P-post-labeling assay demonstrated the MT-induced 8-oxodG adduct formation in calf thymus DNA. Thus, it is concluded that MT, as a potent oxidative stressor, produces ROS leading to mitochondrial dysfunction, oxidative DNA damage and mutagenesis.

In the present study, we screened newly synthesized antiviral aminopyrazoloquinoline derivatives for their cytotoxic and genotoxic potential in human normal and breast cancer cell lines using apoptosis and DNA adducts biomarkers. The compounds, along with the well-known antiviral drug acyclovir, were incubated with the normal (MCF-10A, MCF-12A) and cancer (MCF-7, MDA-MB-231) cell lines at 10, 50, and 100 μM for 72 h at 37°C. The most potent antiviral methoxy derivative (compound 3) was found to be more cytotoxic in the normal breast epithelial cell lines (MCF-10A and MCF-12A) and MDA-MB-231 cell lines at 50 μM. MCF-7 cells were found to be almost completely resistant to all these compounds while MDA-MB-231 cell lines were significantly killed by apoptosis. Acyclovir was ineffective in all these cell lines. We further tested these compounds using modulation of benzo[a]pyrene (BP)-DNA adduct formation in these cell lines. An inverse correlation was found between the degree of apoptosis and BP-DNA adduct levels for most of these compounds, although this seems to be the case only with the cancer cell lines. Our results suggest that the newly synthesized antiviral compounds have an associated risk of cytotoxicity and/or genotoxicity compared to acyclovir.

The marine-derived cembranoid sarcophine (1) and its sulfur-containing semisynthetic derivatives (2–6) were evaluated for anticancer potential using cell cycle progression markers. No effect on MCF-7 cell viability or apoptosis was seen with these derivatives at concentrations of up to 100 μM after 72 h of incubation. At 100 μM, sarcophine and its derivatives 2–5 arrested the MCF-7 cells in G0/G1 phase, with concomitant decrease in the cell populations at S and G2+M phases. MDA-MB-231 cells were not responsive to any of the derivatives. Our preliminary results suggest that the sulfur-containing derivatives of sarcophine, especially 2 and 3, show potent and cell-specific antiproliferative activity.

Several studies have reported the presence of DNA adducts derived from benzo(a)pyrene and other polyaromatics by 32P-postlabeling/TLC by measuring diagonal radioactive zones (DRZs) in lung tissues of human smokers. However, our experimental studies in rodent models, which used modified chromatographic conditions to obtain distinct adduct spots, suggested that cigarette smoke-related lipophilic DNA adducts may not be derived from polycyclic aromatic hydrocarbons (PAHs) or aromatic amines. In the present study, we have performed similar analysis of human lung tissues to study the chemical nature of DNA adducts. Fifty human lung tissues from cancer patients (ages 42-83 years) with active, ex-, or never-smoking status were analyzed for highly lipophilic DNA adducts by nuclease P1- and n-butanol enrichment-mediated 32P-postlabeling assay. All DNA samples yielded low to highly intense adduct DRZs when adducts were resolved by PEI-cellulose TLC in standard high-salt, high-urea solvents. Adduct burden ranged from 6.6 to 2930 per 10(10) nucleotides. However, when adducts were resolved in a different solvent system comprising of high-salt, high-urea in direction 3 and dilute ammonium hydroxide in direction 4, which retained adducts derived from PAHs and aromatic amines on the chromatograms, this yielded no detectable adducts from human lung DNAs. Furthermore, analysis of human lung DNAs mixed with reference adducted DNAs in multisolvent systems confirmed an absence of PAH- and aromatic amine-derived adducts in human smoker lung DNA. To determine the origin of cigarette smoke-associated DNA adducts, calf thymus DNA was incubated with formaldehyde and acetaldehyde, which are known to be present in cigarette smoke in significant quantities. Analysis of purified DNAs by 32P-postlabeling resulted in adduct DRZs in the aldehyde-modified DNAs when adducts were resolved in standard urea-containing solvents, but no adducts were detected when the ammonium hydroxide-based solvent was used, suggesting that even nonpolyaromatic electrophiles can result in adduct DRZs on the chromatograms similar to those from PAH metabolites. Taken together, our data demonstrate that cigarette smoke-associated lung DNA adducts appear on chromatograms as DRZs, consistent with the literature, but they are not related to PAHs and aromatic amines.

In the present study, two of the probable an umor marine compounds, manzamine A and sarcophine, were screened using benzo[a]pyrene (BP)-derived DNA adduct formation in MCF-7 cells as intermediary biomarker. Briefly, MCF-7 cells were treated with the compounds for 24 h followed by treatment with BP (0.5 μM). After 24h incubation, cellular DNA was isolated and analyzed for BP-derived DNA adducts by 32P-postlabeling technique. Manzamine A and sarcophine increased the BP-DNA adducts by 2 to 4-folds. Further, manzamine A (50 μM) substantially down regulated the expression of p53 while sarcophine (50 μM) slightly induced the level of p21. The residual DNA repair ability was almost completely abolished by manzamine A while sarcophine was ineffective. Based on our preliminary results, these compounds may be classified as potential genotoxic.

Several new platinum(II) complexes of the general formulae cis-[PtCl(2)(DMSO)L], where L is a Schiff base or hydrazone derived from tetrazolo[1,5-a]quinoline-4-carboxaldehyde as carrier ligands, have been synthesized and characterized physicochemically and spectroscopically. These platinum complexes which are structurally analogues to what so called cisplatin [cis-[PtCl2(NH3)2]; the first generation anticancer agent] were evaluated for their cytotoxicity on HL-60 (human promyelocytic leukemia) cells. Two of the platinum complexes were almost similar in their activity to cisplatin, while the remaining three complexes have demonstrated higher efficacy than that of cisplatin. Based on our findings, these novel platinum complexes appear to be valuable leading compounds with high efficacy.

In the past several decades, marine organisms have generously gifted to the pharmaceutical industries numerous naturally bioactive compounds with antiviral, antibacterial, antimalarial, anti-inflammatory, antioxidant, and anticancer potentials. But till date only few anticancer drugs (cytarabine, vidarabine) have been commercially developed from marine compounds while several others are currently in different clinical trials. Majority of these compounds were tested in the tumor xenograft models, however, lack of anticancer potential data in the chemical- and/or oncogene-induced pre-initiation animal carcinogenesis models might have cost some of the marine anticancer compounds an early exit from the clinical trials. This review critically discusses importance of preclinical evaluation, failure of human clinical trials with certain potential anticancer agents, the screening tests used, and choice of biomarkers.

Commercial polychlorinated biphenyls (PCBs) are complete carcinogens in rodents, however, their initiating (DNA damaging) activity has not been conclusively demonstrated. In the present study, we reacted synthetic 2-phenyl-1,4-benzoquinones (BQ) and 2-phenyl-1,4-hydroquinones (HQ) of 2-chloro-, 3-chloro-, 4-chloro-, 3,4-dichloro-, and 3,4,5-trichlorobiphenyls with calf thymus DNA and individual deoxynucleoside-3′-monophosphates for 4 h at 37 °C. Analysis of DNA adducts resulting from BQ and HQ derivatives of the test congeners by 32P-postlabeling showed essentially similar adduct patterns. However, the adduct pattern and reactivity differed with the congener used. Quantitatively, 2-chloro-BQ/HQ produced in the highest DNA adduct levels and 3,4,5-chloro-BQ/HQ was the least reactive. Chromatographic comparison of DNA and nucleotide adducts derived from 4-chloro-BQ revealed that cytosine, adenine, and thymidine in the DNA accounted for most of the DNA adducts. Interestingly, none of the adducts in DNA were guanine-derived, even though this mononucleotide was highly reactive. These results suggest that both BQ and HQ derivatives of PCBs are capable of covalently binding to DNA, and chromatographic similarity in adduct patterns resulting from these two metabolites suggest possible involvement of intermediary semiquinone radicals. Experiments are underway to determine their in vivo significance.

Indole-3-carbinol (I3C) found in various cruciferous vegetables has been shown to exert anti-carcinogenic activity in several target organs. In this study, we have investigated the effects of I3C on cigarette smoke-related lipophilic DNA adduct formation, potentially a key step in chemical carcinogenesis. Female Sprague–Dawley rats were exposed to sidestream cigarette smoke in a whole-body exposure chamber for 6 h per day, 7 days a week for 4 weeks. Control animals received only vehicle while the intervention groups received I3C (1.36 or 3.40 mmol/kg, b.wt.) daily by gavage starting from 1 week prior to smoke initiation until the end of the experiment. Analysis of tissue DNA by nuclease P1-mediated 32P-postlabeling showed one major and several minor smoke-related adducts in lung, trachea, heart and bladder. The high dose of I3C significantly inhibited the major adducts in lung (#5) and trachea (#3) by 55% each; minor adducts were slightly inhibited (20–40%). The low dose of I3C showed lesser degree of inhibition (30–40%) in both lung and trachea; however, it was found statistically significant in lung only. The major smoke-related adduct in bladder (#2) was strongly inhibited (>65%) by high dose of I3C approaching adduct levels achieved in sham-exposed rats. A small but statistically significant decrease in the smoke-related DNA adduct (#5) in heart tissue was also observed by intervention with high dose I3C. Low levels (30–50 adducts/1010 nucleotides) of I3C-derived DNA adducts were also found in all the tissues examined although their significance remains unknown. These data show significant inhibition of cigarette smoke-related DNA adducts by I3C, particularly in the lung, trachea, and bladder.

Bay-region diol epoxides are considered the putative ultimate carcinogens of polynuclear aromatic hydrocarbons. However, the results of studies on tumorigenesis and DNA binding of benzo[ a ]pyrene (BP) and its bay-region diol epoxide, (+)- trans -7,8-dihydroxy- anti -9,10-epoxy-7,8,9,10-tetrahydrobenzo[ a ]pyrene [(+)- anti -BPDE] suggest that, in addition to anti -BPDE, other reactive metabolite(s) of BP may also be involved in BP-induced carcinogenesis. Recent studies have demonstrated that 3-hydroxy- trans -7,8-dihydroxy- anti -9,10-epoxy-7,8,9,10-tetrahydrobenzo[ a ]pyrene ( anti -BPTE) is another highly reactive metabolite of BP. In order to identify syn - and anti -BPTE-derived DNA adducts and their base selectivity, we synthesized both compounds by two different methods and reacted in vitro with calf thymus DNA and individual nucleotides. The resultant adducts were analyzed by nuclease P1-enhanced 32 P-postlabeling. Anti -BPTE produced three major and several minor adducts with DNA; dAp and dGp were the preferred substrates, while dCp and dTp were the least reactive. In contrast, syn -BPTE produced two major adducts each with DNA and dGp; dAp generated only one adduct. Co-chromatography of anti -BPTE-derived DNA adducts with those of mononucleotide adducts revealed that the major adducts in DNA were guanine derived. Further, co-chromatographic results revealed that the anti -BPTE-DNA adducts were distinctly different from that of anti -BPDE-DNA adducts. These observations indicate that both syn - and anti -BPTE can react with DNA bases and these DNA adducts may also contribute to BP-induced carcinogenesis.

Exposure to tobacco smoke has been implicated in the increased incidence of cancer and cardiovascular diseases. This report describes various experimental studies in animals that were carried out to determine the ability of cigarette smoke to form DNA adducts and to define chromatographic nature of the major adducts. Tissues from rodents exposed to mainstream or sidestream cigarette smoke in nose-only and whole-body exposure systems, respectively, for different durations were analyzed for DNA adducts by 32 P -postlabeling assay. The results showed essentially similar qualitative patterns in various respiratory (lung, trachea, larynx) and non-respiratory (heart, bladder) tissues of smoke-exposed rats. However, adduct pattern in the nasal mucosa was different. The mean total DNA adducts in various tissues expressed as per 10 10 nucleotides exhibited the following order: heart (700)>lung (420)>trachea (170)>larynx (150)>bladder (50). Some qualitatively identical adducts were routinely detected in tissues from sham-treated rats but at greatly reduced levels (5- to 25-fold). The levels of lung DNA adducts increased with the duration of exposure up to 23 weeks and returned to control levels 19 weeks after the cessation of exposure. Species-related differences in adduct magnitude and patterns were observed among rats, mice and guinea pigs; mouse being the most sensitive to DNA damage and guinea pig the least sensitive. Whole-body exposure of rats to sidestream cigarette smoke also enhanced the pre-existing DNA adducts by several fold in different tissues. Selective chromatography, and extractability in butanol suggested lipophilic nature of smoke-associated DNA adducts, which were, however, recovered significantly better in nuclease P1 than butanol enrichment procedure. The major smoke-associated adducts were chromatographically different from any of the reference adducts of polycyclic aromatic hydrocarbons (PAHs) co-chromatographed with the smoke DNA samples. Because PAH–DNA adducts are recovered with equal efficiency by the two enrichment procedures, the above observations suggested that smoke-associated adducts are not related to typical PAHs, like benzo[ a ]pyrene. It is concluded that cigarette smoke increased the levels of pre-existing endogenous DNA adducts (the so-called I-compounds) in animal models and that these adducts are unrelated to those formed by typical PAHs.

Due to the large and expanding number of potential cancer chemopreventive agents, there is an increasing need for short term tests to study the efficacy and mechanisms of these agents. In this study, we have employed a microsome-mediated test system to study the effect of several suspected chemopreventive agents on the DNA adduct formation capacity of the potent mammary carcinogen, dibenzo[ a,l ]pyrene (DBP). Bioactivation of DBP by Aroclor 1254-induced rat liver microsomes in the presence of calf thymus DNA (300 μ g/ml) resulted in the formation of one major and six other prominent DNA adducts (324 adducts/10 7 nucleotides). These adducts were previously determined to be deoxyadenosine (dA) and deoxyanosine (dG)-derivatives of both anti - and syn -DBP-11,12-diol-13,14-epoxides (DBPDE). Intervention with ellagic acid, chlorophyllin, benzyl isocyanate (BIC), oltipraz or genistein (150 μ M) strongly diminished DBP–DNA adduction by ≥75%. Linoleic acid, curcumin and butylated hydroxytoluene (BHT) also significantly inhibited DBP–DNA adduction (26–46%) while N -acetylcysteine (NAC) had no effect. Moreover, nonenzymatic studies with anti - and syn -DBPDE isomers revealed that chlorophyllin, ellagic acid, BIC and BHT may be inhibiting DBP–DNA adduction in an enzymatic-independent manner since these agents diminished DBPDE–DNA adduction by 30–75%. Genistein, oltipraz and curcumin did not diminish DBPDE–DNA adduction and therefore most likely require the presence of the microsomal subcellular fraction to inhibit DBP–DNA adduction.

Several observations, including studies from this laboratory, demonstrate that asbestos generates free radicals in the biological system that may play a role in the manifestation of asbestos-related cytotoxicity and carcinogenicity. It has also been demonstrated that iron associated with asbestos plays an important role in the asbestos-mediated generation of reactive oxygen species. Exposure to asbestos leads to degradation of heme proteins such as cytochrome P450-releasing heme in cytosol. Our simulation experiments in the presence of heme show that such asbestos-released heme may increase lipid peroxidation and can cause DNA damage. Further, heme and horseradish peroxidase (HRP) can cause extensive DNA damage in the presence of asbestos and hydrogen peroxide/organic peroxide/hydroperoxides. HRP catalyzes oxidation reactions in a manner similar to that of prostaglandin H synthetase. Iron released from asbestos is only partially responsible for DNA damage. However, our studies indicate that DNA damage mediated by asbestos in vivo may be caused by a combination of effects such as the release and participation of iron, heme, and heme moiety of prostaglandin H synthetase in free radical generation from peroxides and hydroperoxides.

This study describes in silico validation of the wet lab data from aeroplysinin-1, curcumin and halofuginone using Autodock Tools 4.0. The inhibition patterns of the vascular endothelial cell differentiation and capillary tube formation mediated by anti-angiogenic growth factors from these test compounds were found quite comparable with the in silico results using angiogenic targets (EFGR, bFGF and VEGFR-1). Successful validation of the wet lab results of the selected angiogenic targets by in silico method has led to exploit the hidden potential of in silico tools in preliminary screening of the unknown compounds for anti-angiogenic potential in a cost-effective manner.

Our previous studies suggested that body fluids such as serum can serve as a novel surrogate for DNA-containing tissues to overcome the major limiting factor of tissue availability in human biomonitoring assessments. We have now examined the detectability of DNA-reactive metabolites (DRMs) in the serum and tissues of male C57BL/6 mice administered up to 10 i.p. injections on alternate days of individual polynuclear aromatic hydrocarbons (PAHs) or a mixture containing 0.01, 0.1, 1.0 and 5.0 mg/kg body wt each of benzo[a]pyrene (BP), cyclopenta[cd]pyrene (CPP) and benzo[k]fluoranthene (BF) in 200 microl sunflower oil. Four hours after the last dose, blood serum was separated and incubated with salmon testes DNA (st-DNA). 32P-Postlabeling of the st-DNA showed essentially the same adduct pattern as found in the tissue DNA, indicating that DRMs of the PAHs used were presumably sequestered and accumulated in the serum proteins. Serum DRMs were detectable at all doses tested following exposure to a mixture of BP, CPP and BF, with varying degrees of detection of the individual PAHs. At dosesor = 1 mg/kg, CPP was more potent than BP and BF in producing serum DRMs as well as tissue DNA adducts. At lower doses, however, BP was more potent. Serum DRMs were enhanced 7-20 times when the animals received 1 mg/kg each of these PAHs in the form of a mixture as compared with individual PAHs, however, tissue DNA adduction was enhanced to a lesser degree (1.5- to 2-fold). Results from these studies suggest that: (i) DNA adduction by a particular carcinogen can be significantly higher when administered in the form of a mixture than administered individually; (ii) DNA-reactive metabolites can be detected by 32P-postlabeling in the serum of animals treated with environmentally significant doses of an artificial carcinogen mixture. This approach has implications for human biomonitoring and offers an advantage because this obviates the need to acquire human tissue DNA, a major obstacle in population biomonitoring studies.

Asbestos is known to induce oxidative stress in the lung. The consumption of butylated hydroxyanisole (BHA) in preserved food and soft drinks is increasing in the general population, which includes workers in asbestos factories. Because there is no information on the effect of co-exposure to chrysotile and BHA, the time-dependent effects of a single intratracheal dose of chrysotile (1 mg per mouse) and a single ip dose of BHA (350 mg/kg body weight) on various indices of oxidative stress such as lipid peroxidation, hydrogen peroxide generation, glutathione peroxidase (GPX), glutathione reductase (GR), catalase, glucose-6-phosphate dehydrogenase (G6PDH) and glutathione (GSH) were followed for up to 14 days. Microsomal lipid peroxidation (as well as that induced by NADPH) was significantly enhanced by BHA in the chrysotile-exposed group. GPX and GR activities in the same group were gradually decreased by BHA. Non-significant modulation of catalase activity by BHA was also noted. BHA induces GSH to a significant extent in lungs exposed with chrysotile. An increase in the G6PDH activity was maximal (19%; P < 0.05) at day 3. The results clearly demonstrate that BHA enhances chrysotile-induced oxidative stress in the lung.

Amylases have most widely been reported to occur in microorganisms, although they are also found in plants and animals. Microbial cold-active α-amylases confer high activities at low temperature that favours production of comparatively insubstantial compounds. Cold-active α-amylases have an advantage under extreme low temperature conditions due to their freeze tolerance mechanism, intrinsic greater membrane fluidity and production of cold-acclimation proteins. Due to considerable progress towards energy savings process in industries, the low temperature stability has been regarded as the most important characteristics of cold-active amylases. Cold active enzymes attract more and more attention nowadays. Comparatively little information is available on cold-active microbial α-amylases and its catalytic properties. Now the situation is changing which recently enchanted the scientific community to focus in various fields, such as analytical, medicinal and clinical chemistry, as well as their extensive industrial applications such as starch industry, food processing, additive in detergents, waste-water treatment, biopulping, textile industry, environmental bioremediation in cold climates and other molecular biology applications. Key words: Psychrophiles, psychrotrophs, extremozymes, cold-active amylase, starch degrading enzymes.

In the recent years, a number of bioactive peptides and their analogues from cyanobacteria with promising anticancer, antiviral, antibacterial, antifungal, antioxidant, and molluscicidal potentials have been reported. Some of them have even made it into the clinical trials for treatment of cancer and other degenerative diseases. This chapter will focus on some of the significant bioactive peptides and their analogues, biosynthesis, and bioactivity.

The unwarranted connection between diabetes mellitus and breast cancer has gained new ground in recent years. Breast cancer in Saudi females accounts for approximately 21% of all cancers and the prevalence of diabetes mellitus (DM) in Saudi females is also 21.5%. DM is diagnosed in the age group of 30+ years with possible exposure to predisposing factors like hyperinsulinemia and obesity at younger age. Further, 12% of the breast cancer cases are diagnosed in the young females aged 20-34 years. Despite the readily available access to healthcare facilities in the Kingdom, a large number of diabetics, approximately 27.9%, were unaware of having diabetes mellitus. This subpopulation is quite susceptible of developing breast cancer at later age. This review discusses common etiological and predisposing factors for breast cancer and diabetes, regional distribution and possible correlation of diabetes and cancer in Saudi Arabia.

In this study, we used DNA adducts as the endpoint to reflect on the type and amount of electrophilic metabolites formed in a cell-free system, which were 'trapped' with DNA and the resultant adducts analyzed by a highly sensitive (32)p- postlabeling assay. Incubation of benzo[a]pyrene (BP) (10 mu M) with liver microsomes and S-9 fractions from uninduced and beta-naphthoflavone (beta-NF)-induced rats and NADPH-generating system resulted in two major adducts, one derived from the interaction of benzo[a]pyrene diolepoxide with deoxyguanosine (BPDE-dG) and the other from further activation of 9-OH-BP. beta-NF treatment increased the microsomal DNA adduction capability: both BPDE-dG and 9-OH-BP adducts were enhanced to 19,600 and 26,600 adducts/10(9) nucleotides compared to 2,800 and 1,700 adducts/10(9) nucleotides with uninduced microsomes, respectively. An even greater enhancement of both adducts was observed when S-9 was substituted for microsomes. These results suggest the involvement of CYP1A1 in BP activation because of the known role of beta-NF in the induction of this enzyme. Further, evidence of the involvement of CYP1A1 was obtained by using alpha-naphthoflavone (alpha-NF), a known inhibitor of CYP1A family. Addition of alpha-NF (50 mu M) to the activation system almost completely (>95%) abolished both the adducts. These results are consistent with selective inhibition of CYP1A1, the isozyme involved in the conversion of BP to BP-7,8-diol. Further, cyclohexene oxide (Chox) (100 mu M), a known inhibitor of epoxide hydrolase reduced BPDE-dG adduct by 55% over that in the absence of the inhibitor, suggesting its epoxide origin; 9-OH-BP adduct was, however slightly increased. Enhanced DNA adduction of another class of carcinogen, 2-acetylaminofluorene (2-AAF) (20 mu M) with induced S-9 and microsomes, and inhibition in the presence of alpha-NF was also observed which is consistent with the involvement of CYP1A2 in the initial activation of aromatic amines. Results from these experiments suggest that the approach of using a battery of inducer/inhibitor probes and their influence on DNA adduction capability of subcellular fractions coupled with P-32-postlabeling can be fully exploited as important tools in defining metabolic pathway(s) that may be involved in the bioactivation of unknown compounds.

Multidrug resistance (MDR) in microorganisms is a cause of major concern for clinicians and pharmaceutical industries. Continuous development of new antimicrobial drugs with multiple targets and potentials is expected to efficiently combat MDR in these microorganisms. In a continued exploration of new antimicrobial drug leads, 11 marine natural products, semisynthetic, or related synthetic analogs (1-11) and two tobacco cembranoids (12 and 13) were screened for their antimicrobial, antioxidant, and antimutagenic activities. Eight compounds showed varying levels of both antibacterial and antifungal activities. Compounds such as 17-O-methyllatrunculin-A, verongiaquinol, (1S,2E,4R,6R,7E,11E)-2,7,11-cembratriene-4,6-diol), and manzamine-A showed a broad spectrum of activity, inhibiting six of seven tested bacteria with zone of inhibition diameter from 9 to 30 mm. Four of these active compounds also showed antifungal activity. The findings of the in vitro time-kill assay of the most active compound, verongiaquinol, against Staphylococcus aureus indicated its subinhibitory effect at the level lower than the minimal inhibitory concentration (MIC) values (i.e., 2 and 4 µg/mL). At the MIC (8 µg/mL), bacterial cells were completely killed within 18 hours of incubation. DPPH free radical scavenging activity was demonstrated by five compounds in the range of 89.65-36.19% decolorization. Further, four compounds evaluated for their antimutagenic activity against the directly acting mutagens, methyl methanesulfonate and sodium azide, in Salmonella typhimurium strains, interestingly, showed no sign of mutagenicity. Verongiaquinol and manzamine A, in fact, reduced the mutagenicity by 50-75% at a dose of 5 µg/plate in different test strains. Our study seems to provide some novel antimicrobial leads with strong antioxidant potential and the associated ability of antimutagenicity.

The involvement of reactive oxygen species (ROS) in the cytotoxicity of soot on rat alveolar macrophages has been postulated. A single intratracheal injection of soot (5 mg) in corn oil significantly induced the macrophage population, hydrogen peroxide (H2O2) generation, thiobarbituric acid (TBA)-reactive substances of lipid peroxidation, and the activities of extracellular acid phosphatase (AP) and lactate dehydrogenase (LDH) at 1, 4, 8, and 16 days of postinoculation. The activities of glutathione peroxidase (GPX) and catalase (CAT) were significantly inhibited at all the stages, while glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PD) showed a different pattern. These results show that soot is cytotoxic to alveolar macrophages and suggest that ROS may play a primary role in the cytotoxic process.

This study is designed to investigate the impact of DNA damage on pregnancy and fertilization rate outcome in a sub-sample of women undergoing IVF treatment. Blood and follicular fluid samples (n = 60) were analyzed for DNA adducts. While no BPDE-DNA adducts were detected, other unknown lipophilic adducts were seen in blood and follicular fluid. Women who failed to achieve pregnancy had higher DNA adducts in follicular fluid than those who succeeded (p

In order to determine the pulmonary toxicity of kerosene and its ignition product (soot) in asbestos exposed subjects, the activities of phase I and phase II drug metabolizing enzymes in rat lungs after single intratracheal coexposure to Indian chrysotile asbestos and kerosene or its soot and Indian chrysotile were assayed. Exposure to kerosene or its soot resulted in a significant increase in the level of microsomal cytochrome P-450 and the activity of P-450 dependent monooxygenase, benzo(a)pyrene hydroxylase, as well as in the activities of microsomal epoxide hydrase and cytosolic glutathione-S-transferase (GST). However, in chrysotile exposed animals a reverse pattern in these parameters was recorded. The co-exposure to chrysotile and kerosene or chrysotile and soot led to a significant depletion in cytochrome P-450 level and a decrease in the activities of benzo(a)pyrene hydroxylase, epoxide hydrase and GST when compared to kerosene and soot controls, respectively. These results suggest that asbestos by altering the pulmonary drug metabolizing enzyme system may increase the toxic potential of kerosene and its ignition product in the respiratory system.

A large variety of ornamental and decorative items are manufactured from bone waste by various unorganized sectors in India. An initial survey indicated that workers were exposed at various phases of final product. The subjects (12 industrial units) were tested for total suspended particulate matter (TSPM), particulate matter

The activities of enzymes, which detoxify oxygen free radical species directly or indirectly were studied in lungs of kerosene-treated rats after 1,4,8 and 16 days of exposure. In the kerosene-exposed animals, activities of glutathione peroxidase (GP), glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G6PD) and glutathione-s-transferase (GST) were significantly increased; thiobarbituric acid (TBA) - reacting products of lipid peroxidation and reduced glutathione (GSH) content were also significantly increased in the lungs. The increase in reduced glutathione content and elevations in the activities of enzymes and products of lipid peroxidation are suggestive of oxidative stress in the lungs of kerosene exposed animals.