bluuebunny/crossref_metadata_2025 huggingface dataset:
Curcumin: Getting Back to the Roots
Authors: SHISHODIA SHISHIR , SETHI GAUTAM , AGGARWAL BHARAT B.
Published: December 2005

The use of turmeric, derived from the root of the plantCurcuma longa, for treatment of different inflammatory diseases has been described in Ayurveda and in traditional Chinese medicine for thousands of years. The active component of turmeric responsible for this activity, curcumin, was identified almost two centuries ago. Modern science has revealed that curcumin mediates its effects by modulation of several important molecular targets, including transcription factors (e.g., NF‐κB, AP‐1, Egr‐1, β‐catenin, and PPAR‐γ), enzymes (e.g., COX2, 5‐LOX, iNOS, and hemeoxygenase‐1), cell cycle proteins (e.g., cyclin D1 and p21), cytokines (e.g., TNF, IL‐1, IL‐6, and chemokines), receptors (e.g., EGFR and HER2), and cell surface adhesion molecules. Because it can modulate the expression of these targets, curcumin is now being used to treat cancer, arthritis, diabetes, Crohn's disease, cardiovascular diseases, osteoporosis, Alzheimer's disease, psoriasis, and other pathologies. Interestingly, 6‐gingerol, a natural analog of curcumin derived from the root of ginger (Zingiber officinalis), exhibits a biologic activity profile similar to that of curcumin. The efficacy, pharmacologic safety, and cost effectiveness of curcuminoids prompt us to “get back to our roots”
Thiolsulfinate Allicin from Garlic: Inspiration for a New Antimicrobial Agent
Authors: HUNTER ROGER , CAIRA MINO , STELLENBOOM NASHIA
Published: December 2005

Consideration of the underlying features responsible for garlic‐allicin's antimicrobial activity as well as its instability has prompted an investigation into substituted S‐aryl alkylthiolsulfinates as a class of garlic mimic with enhanced stability. Synthesis of the targets has inspired the development of new methods for synthesizing unsymmetrical aralkyl disulfides, which are then oxidized to the targets. Some simple representatives have been synthesized, setting the scene for a full SAR study of this relatively unexplored class of thiolsulfinate.
Mediterranean Diet and Cardiovascular Health
Authors: GIUGLIANO DARIO , ESPOSITO KATHERINE
Published: December 2005

Diets that are high in fruits, vegetables, legumes, and whole grains and include fish, nuts, and low‐fat dairy products have protective health effects. The traditional Mediterranean diet encompasses these dietary characteristics. Other compounds of the Mediterranean diet, the antioxidants, which exist in abundance in vegetables, fruit, beverages, and also virgin olive oil, may contribute to the prevention of coronary heart disease and possibly several forms of cancer and other diseases, thus providing a plausible explanation for its apparent benefits. It may be misleading to focus on a single element of the diet; this may explain, at least in part, the disappointing and frustrating results obtained in trials with vitamin supplementation, prematurely thought to be “the magic bullet” for preventing a myriad of chronic diseases. The results of intervention studies aimed at evaluating whether Mediterranean‐type diets are superior to classic diets in the secondary prevention of coronary heart disease have all been encouraging. The biologic mechanisms by which these compounds might exert their effects include, among others, antioxidant functions and induction of detoxification enzymes. However, from a public health perspective it is not essential to wait for elucidation of every mechanism underlying health promotion activities and interventions; given the simplicity of the diet quality score, increasing the intake of recommended foods represents a practical recommendation for improving health.
Novel Drugs and Vaccines Based on the Structure and Function of HIV Pathogenic Proteins Including Nef
Authors: AZAD AHMED A.
Published: December 2005

Evidence is presented to suggest that HIV‐1 accessory protein Nef could be involved in AIDS pathogenesis. When present in extracellular medium, Nef causes the death of a wide variety of cells in vitro and may therefore be responsible for the depletion of bystander cells in lymphoid tissues during HIV infection. When present inside the cell, Nef could prevent the death of infected cells and thereby contribute to increased viral load. Intracellular Nef does this by preventing apoptosis of infected cells by either inhibiting proteins involved in apoptosis or preventing the infected cells from being recognized by CTLs. Neutralization of extracellular Nef could prevent the death of uninfected immune cells and thereby the destruction of the immune system. Neutralization of intracellular Nef could hasten the death of infected cells and help reduce the viral load. Nef is therefore a very important molecular target for developing therapeutics that slow progression to AIDS. The N‐terminal region of Nef and the naturally occurring bee venom mellitin have very similar primary and tertiary structures, and they both act by destroying membranes. Chemical analogs of a mellitin inhibitor prevent Nef‐mediated cell death and inhibit the interaction of Nef with cellular proteins involved in apoptosis. Naturally occurring bee propolis also contains substances that prevent Nef‐mediated cell lysis and increases proliferation of CD4 cells in HIV‐infected cultures. These chemical compounds and natural products are water soluble and nontoxic and are therefore potentially very useful candidate drugs.
Anti‐HIV, Anti‐Poxvirus, and Anti‐SARS Activity of a Nontoxic, Acidic Plant Extract from the Trifollium Species Secomet‐V/anti‐Vac Suggests That It Contains a Novel Broad‐Spectrum Antiviral
Authors: KOTWAL GIRISH J. , KACZMAREK JENNIFER N. , LEIVERS STEVEN , GHEBREMARIAM YOHANNES T. , KULKARNI AMOD P. , BAUER GABRIELE , DE BEER CORENA , PREISER WOLFGANG , MOHAMED ABDU RAHMAN
Published: December 2005

Enveloped animal viruses such as human immunodeficiency virus (HIV), hepatitis B virus, hepatitis C virus, human papillomavirus, Marburg, and influenza are major public health concerns around the world. The prohibitive cost of antiretroviral (ARV) drugs for most HIV‐infected patients in sub‐Saharan Africa and the serious side effects in those who have access to ARV drugs make a compelling case for the study of complementary and alternative therapies. Such therapies should have scientifically proved antiviral activity and minimal toxic effects. A plant extract, Secomet‐V, with an anecdotal indication in humans for promise as an anti‐HIV treatment, was investigated. Using a previously described attenuated vaccinia virus vGK5, we established the antiviral activity of Secomet‐V. Chemical analysis showed that it has an acidic pH, nontoxic traces of iron (<10 ppm), and almost undetectable levels of arsenic (<1.0 ppm). The color varies from colorless to pale yellow to dark brown. The active agent is heat stable at least up to sterilizing temperature of 121°C. The crude plant extract is a mixture of several small molecules separable by high‐pressure liquid chromatography. The HIV viral loads were significantly reduced over several months in a few patients monitored after treatment with Secomet‐V. Secomet‐V was also found to have antiviral activity against the SARS virus but not against the West Nile virus. Secomet‐V, therefore, is a broad‐spectrum antiviral, which possibly works by neutralizing viral infectivity, resulting in the prevention of viral attachment.
Punica granatum (Pomegranate) Juice Provides an HIV‐1 Entry Inhibitor and Candidate Topical Microbicide
Authors: NEURATH A ROBERT , STRICK NATHAN , LI YUN‐YAO , DEBNATH ASIM K.
Published: December 2005

For ∼24 years the AIDS pandemic has claimed ∼30 million lives, causing ∼14,000 new HIV‐1 infections daily worldwide in 2003. About 80% of infections occur by heterosexual transmission. In the absence of vaccines, topical microbicides, expected to block virus transmission, offer hope for controlling the pandemic. Antiretroviral chemotherapeutics have decreased AIDS mortality in industrialized countries, but only minimally in developing countries. To prevent an analogous dichotomy, microbicides should be acceptable, accessible, affordable, and accelerative in transition from development to marketing. Already marketed pharmaceutical excipients (inactive materials of drug dosage forms) or foods, with established safety records and adequate anti‐HIV‐1 activity, may provide this option. Therefore, fruit juices were screened for inhibitory activity against HIV‐1 IIIB using CD4 and CXCR4 as cell receptors. The best juice was tested for inhibition of: (1) infection by HIV‐1 BaL, utilizing CCR5 as the cellular coreceptor, and (2) binding of gp120 IIIB and gp120 BaL, respectively, to CXCR4 and CCR5. To remove most colored juice components, the adsorption of the effective ingredient(s) to dispersible excipients and other foods was investigated. A selected complex was assayed for inhibition of infection by primary HIV‐1 isolates. The results indicate that HIV‐1 entry inhibitors from pomegranate juice adsorb onto corn starch. The resulting complex blocks virus binding to CD4 and CXCR4/CCR5 and inhibits infection by primary virus clades A to G and group O. Therefore, these results suggest the possibility of producing an anti‐HIV‐1 microbicide from inexpensive, widely available sources, whose safety has been established throughout centuries, provided that its quality is adequately standardized and monitored.
Strategies for Human Papillomavirus Therapeutic Vaccines and Other Therapies Based on the E6 and E7 Oncogenes
Authors: GOVAN V A
Published: December 2005

High‐risk human papillomaviruses (HR‐HPVs) are one of the most devastating oncogenic viruses worldwide and have been causally linked with the development of human cervical cancer. Several prophylactic and therapeutic clinical HPV vaccine trials are in progress. Although prophylactic vaccines are useful in preventing the incidence of cervical cancer, the elimination of existing HPV infections needs to be addressed, because cervical cancer is the leading female cancer in developing countries. Several different and encouraging strategies have been investigated in a preclinical and clinical setting for the treatment and elimination of existing HPV‐induced infection. This review summarizes the therapeutic clinical trials and the different preclinical research strategies that are under investigation whereby HR‐HPV E6 and E7 oncogenes are delivered in a nucleic acid form, in viral and bacterial vectors, or as peptide‐ and protein‐based vaccines.
Development and Evaluation of a Suppository Formulation Containing Lactobacillus and Its Application in Vaginal Diseases
Authors: KALE VINITA V. , TRIVEDI RASHMI V. , WATE SANJAY P. , BHUSARI KISHOR P.
Published: December 2005

Lactobacillus has long been considered the protective flora in the vagina that displaces and kills vaginal pathogens. Lactic acid, H2O2, and antibacterial agents such as lactocin and bacitracin produced by Lactobacillus act against the vaginal pathogens. The first objective of this research was to develop a local application pharmaceutical formulation of a vaginal suppository containing lyophilized culture of Lactobacillus. The second objective was to establish its in vivo performance by developing in vitro methods of evaluation. Lyophilized culture of Lactobacillus sporogenes was selected for this study. Three formulations of the suppositories were prepared by the molding method. Formulations I, II, and III contained cocoa butter, glycerinated gelatin, and PEG 1000 base, respectively. The prepared suppositories were characterized for physical properties. Assembly to simulate the application site was designed. Methods to evaluate the viability, production of lactic acid, and H2O2 produced by the released Lactobacillus at the application site were developed and the antagonistic activity was demonstrated. From the physical characteristics of the suppository formulations, the glycerinated gelatin suppository (formulation II) containing lyophilized Lactobacillus was found to be satisfactory. The developed assembly was satisfactory in simulating the application site. The Lactobacillus released was viable and exhibited the production of lactic acid, hydrogen peroxide, and antagonistic activity against the uropathogen. The suppository formulation containing Lactobacillus and the methods of its evaluation were successfully developed in this research work and have several applications in the vaginal diseases of women.
TRAIL (TNF‐Related Apoptosis‐Inducing Ligand) Induces Necrosis‐Like Cell Death in Tumor Cells at Acidic Extracellular pH
Authors: MEURETTE OLIVIER , HUC LAURENCE , REBILLARD AMELIE , LE MOIGNE GWENAELLE , LAGADIC‐GOSSMANN DOMINIQUE , DIMANCHE‐BOITREL MARIE‐THERESE
Published: December 2005

How tumor microenvironment, more specifically low extracellular pH (6.5), alters cell response to TNF‐related apoptosis‐inducing ligand (TRAIL)‐based cancer therapy has yet to be determined. The aim of the current work was to test the effect of acidic extracellular pH on TRAIL‐induced cell death in human HT29 colon carcinoma and HepG2 hepatocarcinoma cell lines as well as in human primary hepatocytes. We found an increase in TRAIL sensitivity at low extracellular pH, which is partially inhibited by Bcl‐2 expression in HT29 cells. At low extracellular pH, TRAIL induced a new form of cell death, sharing necrotic and apoptotic features in tumor cells. By contrast, human primary hepatocytes were resistant to TRAIL‐induced cell death even at acidic extracellular pH.
Cloning and Expression of a Functionally Active Truncated N‐Glycosylated KSHV ORF4/KCP/Kaposica in the Methylotrophic Yeast Pichia pastoris
Authors: GOMES PEREIRA NEUZA A. , JULIANO MARIA A. , CARMONA ADRIANA K. , STURROCK EDWARD D. , KOTWAL GIRISH J.
Published: December 2005

Kaposi's sarcoma herpesvirus (KSHV) is a typical DNA virus that is associated with a number of proliferative diseases including Kaposi's sarcoma. The KSHV open reading frame (ORF) 4 encodes a complement regulatory protein (Kaposi complement control protein, KCP) that binds complement components and inhibits the complement‐mediated lysis of cells infected by the virus, thus providing a strategy for evasion of the host complement system. Based on primary sequence analysis and comparison with other functionally and structurally similar proteins, oligonucleotide primers were designed to amplify by polymerase chain reaction (PCR) three regions of the predicted ORF 4 from human herpes virus‐8 (HHV‐8) DNA isolated from a primary effusion lymphoma cell line. The PCR products were inserted by ligation into the expression vector pPIC9 to generate three recombinant plasmids for heterologous expression in the yeast, Pichia pastoris, to produce separately the four N‐terminal sushi domains (KCP‐S, small), KCP protein lacking the putative transmembrane‐binding domain (KCP‐M, medium), and the full‐length protein (KCP‐F, full). Expression of the viral proteins was confirmed by SDS‐PAGE, immunologic detection, and Western blot analyses using a rabbit polyclonal antibody directed against a selected peptide region that is common to all three recombinant KCPs. KCP‐S directly from expression media could inhibit complement‐mediated lysis of sensitized sheep erythrocytes by approximately 60% in a hemolysis assay. This result confirms previous reports that recombinant KCP is twice as efficient in inhibiting the classic pathway‐mediated lysis of erythrocytes than is the vaccinia virus complement control protein, which also contains four sushi domains.
Herbal Complement Inhibitors in the Treatment of Neuroinflammation: Future Strategy for Neuroprotection
Authors: KULKARNI AMOD P. , KELLAWAY LAURIE A. , KOTWAL GIRISH J.
Published: December 2005

The upregulated complement system plays a damaging role in disorders of the central nervous system (CNS). The classical and alternate pathways are two major pathways activated in neuroinflammatory disorders such as Alzheimer's disease, multiple sclerosis, traumatic brain injury, spinal cord injury, HIV‐associated dementia, Parkinson's disease, and mad cow disease. Failure of currently available anti‐inflammatory agents, especially cycloxygenase inhibitors, in offering significant neuroprotection in large epidemiologic clinical trials of CNS disorders suggests an urgent need for the development of new neuroprotective agents. The positive preclinical outcomes in treating CNS disorders by complement regulatory molecules, such as vaccinia virus complement control protein, suggest the possibility of using complement‐inhibitory molecules as neuroprotective agents. Several active ingredients of herbal origin are found to have complement‐inhibitory activity. These herbal ingredients along with other anti‐inflammatory roles might be useful in treating neuroinflammation associated with CNS disorders. Active ingredients of herbal origin with complement inhibitory ingredients are summarized and classified according to their chemical nature and specificity towards the major pathways activating the complement system. The structure activity relationship of some specific examples is also discussed in this report. This information might be helpful in formulating a natural panacea against complement‐mediated neuroinflammation.
Administration of Vaccinia Virus Complement Control Protein Shows Significant Cognitive Improvement in a Mild Injury Model
Authors: PILLAY NIRVANA S. , KELLAWAY LAURIE A. , KOTWAL GIRISH J.
Published: December 2005

Previous studies have shown that traumatic mild brain injury in a rat model is accompanied by breakdown of the blood brain barrier and the accumulation of inflammatory cells. A therapeutic agent, vaccinia virus complement control protein (VCP), inhibits both the classic and the alternative pathways of the complement system and, in so doing, prevents cell death and inflammation. With the use of a rat mild injury model, the effects of VCP on spatial learning and memory were tested. Training in a Morris water maze consisted of a total of 16 trials over a 2‐day period before rats were anesthetized and subjected to mild (1.0‐1.1 atm) lateral fluid percussion injury (FPI) 3.0 mm lateral to the sagittal suture and 4.5 mm posterior to bregma. Ten μl of VCP (1.7 mg/ml) was injected into the injury site immediately after FPI. Two weeks post‐FPI the rats were assessed in the Morris water maze for spatial learning and memory. Neurologic motor function tests were carried out after FPI for 14 consecutive days and again after 28 days. The Morris water maze data show that FPI plus saline‐injected rats spent a significantly (P <0.05) larger amount of time in one of the incorrect quadrants than did the FPI plus VCP‐injected group. Neurologic evaluations 24 hours postinjury revealed differences in sensorimotor function between groups. The results suggest that in a mild injury model, VCP influences neurologic outcome and offers some enhancement in spatial memory and learning.
Novel Peptides of Therapeutic Promise from Indian Conidae
Authors: GOWD K HANUMAE , SABAREESH V , SUDARSLAL S , IENGAR PRATHIMA , FRANKLIN BENJAMIN , FERNANDO ANTONY , DEWAN KALYAN , RAMASWAMI MANI , SARMA SIDDHARTHA P. , SIKDAR SUJIT , BALARAM P , KRISHNAN K S
Published: December 2005

Highly structured small peptides are the major toxic constituents of the venom of cone snails, a family of widely distributed predatory marine molluscs. These animals use the venom for rapid prey immobilization. The peptide components in the venom target a wide variety of membrane‐bound ion channels and receptors. Many have been found to be highly selective for a diverse range of mammalian ion channels and receptors associated with pain‐signaling pathways. Their small size, structural stability, and target specificity make them attractive pharmacologic agents. A select number of laboratories mainly from the United States, Europe, Australia, Israel, and China have been engaged in intense drug discovery programs based on peptides from a few snail species. Coastal India has an estimated 20–30% of the known cone species; however, few serious studies have been reported so far. We have begun a comprehensive program for the identification and characterization of peptides from cone snails found in Indian Coastal waters. This presentation reviews our progress over the last 2 years. As expected from the evolutionary history of these venom components, our search has yielded novel peptides of therapeutic promise from the new species that we have studied.
Stabilization of Mitochondrial Membrane Potential and Improvement of Neuronal Energy Metabolism by Ginkgo Biloba Extract EGb 761
Authors: ECKERT ANNE , KEIL UTA , SCHERPING ISABEL , HAUPTMANN SUSANNE , MÜLLER WALTER E.
Published: December 2005

Ginkgo biloba extract EGb 761 has been used for many years to treat age‐related cognitive disorders including Alzheimer's disease. EGb 761 given shortly after initiating mitochondrial damage by sodium nitroprusside (nitric oxide donor) improved the mitochondrial membrane potential of PC12 cells significantly and dose dependently. Under these conditions, EGb 761 also reversed the decrease in ATP production. In addition, similar protection against oxidative damage was found in dissociated brain cells and isolated brain mitochondria afterin vitroorin vivotreatment with EGb 761. Moreover, PC12 cells bearing an Alzheimer's disease‐related mutation in the amyloid precursor protein, which leads to enhanced beta amyloid production, showed greater benefit from treatment with EGb 761 than did control cells. Taken together, our findings clearly show stabilization and protection of mitochondrial function as a specific and very sensitive property of EGb 761 at therapeutically relevant doses.
Humanized Recombinant Vaccinia Virus Complement Control Protein (hrVCP) with Three Amino Acid Changes, H98Y, E102K, and E120K Creating an Additional Putative Heparin Binding Site, Is 100‐fold More Active Than rVCP in Blocking Both Classical and Alternative Complement Pathways
Authors: GHEBREMARIAM YOHANNES T. , ODUNUGA ODUTAYO O. , JANSE KRISTEN , KOTWAL GIRISH J.
Published: December 2005

Vaccinia virus complement control protein (VCP) is able to modulate the host complement system by regulating both pathways of complement activation. Efficient downregulation of complement activation depends on the ability of the regulatory protein to effectively bind the activated third (C3b) and fourth (C4b) complement components. Based on native crystallographic structure, molecular modeling, and sequence alignment with other Orthopoxviral complement control proteins (CCPs) and their host homologs, putative sites have been found on VCP as contact points for C3b/C4b. Here, we report that using site‐directed mutagenesis, modified proteins have been generated. In addition, we report that the generated modified proteins with postulated contact point substitutions have shown greater ability to regulate both the classical and the alternative pathways of complement activation than the recombinant Western Reserve VCP, with one modified protein showing nearly 100‐fold more potency in regulating both complement activation pathways independently. The augmented in vitro inhibitory activity of the modified protein together with the newly created putative heparin binding site suggests its promising potential as a competent therapeutic agent in modulating various complement‐mediated ailments, for example, traumatic brain injury, Alzheimer's disease, rheumatoid arthritis, multiple organ dysfunction syndrome, reperfusion injury, and xenorejection.
Oligomeric Structure of Nitrilases: Effect of Mutating Interfacial Residues on Activity
Authors: SEWELL B T , THUKU R N , ZHANG X , BENEDIK M J
Published: December 2005

Nitrilases are important industrial enzymes that convert nitriles into their corresponding acids or, occasionally, amides. Atomic resolution structures of four members of the nitrilase superfamily have been determined, but these differ from microbial nitrilases in that they do not form typical large homo‐oligomeric complexes. At least two nitrilases, the cyanide dihydratases from Pseudomonas stutzeri AK61 and Bacillus pumilus C1, form unusual spiral structures of 14 and 18 subunits, respectively. Evidence suggests that the formation of the spiral structure is essential for activity. Sequence analysis reveals that the nitrilases differ from the nonspiral‐forming homologs by two insertions of between 12 and 14 amino acids and a C‐terminal extension of up to 35 amino acids. The insertions are positioned at an intermolecular interface in the spiral and probably contribute to its formation. The other interfaces responsible for the formation and/or stabilization of the spirals can also be identified. Comparative structure modeling enables identification of the residues involved in these interacting surfaces, which are remote from the active site. Mutation of these interacting residues usually leads to loss of activity. The effect of the mutations on activity in most cases can be rationalized in terms of a possible effect on spiral formation.
Transcription Factor NF‐κB: A Sensor for Smoke and Stress Signals
Authors: AHN KWANG SEOK , AGGARWAL BHARAT B.
Published: December 2005

Nuclear factor‐kappa B (NF‐κB) is a transcription factor that resides in the cytoplasm of every cell and translocates to the nucleus when activated. Its activation is induced by a wide variety of agents including stress, cigarette smoke, viruses, bacteria, inflammatory stimuli, cytokines, free radicals, carcinogens, tumor promoters, and endotoxins. On activation, NF‐κB regulates the expression of almost 400 different genes, which include enzymes (e.g., COX‐2, 5‐LOX, and iNOS), cytokines (such as TNF, IL‐1, IL‐6, IL‐8, and chemokines), adhesion molecules, cell cycle regulatory molecules, viral proteins, and angiogenic factors. The constitutive activation of NF‐κB has been linked with a wide variety of human diseases, including asthma, atherosclerosis, AIDS, rheumatoid arthritis, diabetes, osteoporosis, Alzheimer's disease, and cancer. Several agents are known to suppress NF‐κB activation, including Th2 cytokines (IL‐4, IL‐13, and IL‐10), interferons, endocrine hormones (LH, HCG, MSH, and GH), phytochemicals, corticosteroids, and immunosuppressive agents. Because of the strong link of NF‐κB with different stress signals, it has been called a “smoke‐sensor” of the body.
Antiulcer and Antioxidant Activity of Asparagus racemosus WILLD and Withania somnifera DUNAL in Rats
Authors: BHATNAGAR MAHEEP , SISODIA SIDDHRAJ S. , BHATNAGAR REKHA
Published: December 2005

Comparative study of the antiulcer and antisecretory activity of Asparagus racemosus Willd (Shatawari) and Withania somnifera Dunal (Ashwagandha) root extract with a standard drug, ranitidine, in various models of gastric ulcer in rats is presented. Ulcer was induced by the indomethacin (NSAID) and swim (restraint) stress treatment. Results demonstrated that A. racemosus as well as W. somnifera methanolic extract (100 mg/kg BW/day p.o.) given orally for 15 days significantly reduced the ulcer index, volume of gastric secretion, free acidity, and total acidity. A significant increase in the total carbohydrate and total carbohydrate/protein ratio was also observed. Study also indicated an increase in antioxidant defense, that is, enzymes superoxide dismutase, catalase, and ascorbic acid, increased significantly, whereas a significant decrease in lipid peroxidation was observed. A. racemosus was more effective in reducing gastric ulcer in indomethacin‐treated gastric ulcerative rats, whereas W. somnifera was effective in stress‐induced gastric ulcer. Results obtained for both herbal drugs were comparable to those of the standard drug ranitidine.
Intervention Strategies and Agents Mediating the Prevention of Xenorejection
Authors: GHEBREMARIAM YOHANNES T. , SMITH SCOTT A. , ANDERSON J B , KAHN D , KOTWAL GIRISH J.
Published: December 2005

Xenotransplantation, the transplantation of cells, tissues, and/or organs across species, has proven to be an enormous challenge, resulting in only limited achievements over the last century. Unlike allotransplantation, the immunologic barriers involved in xenotransplant rejection are aggressive and usually occur within minutes in a hyperacute fashion. The use of organs from phylogenetically related concordant species may not be practical. Discordant xenotransplantation is characterized by hyperacute graft rejection, and to use nonprimate discordant organs for human benefit will require manipulation of the taxonomic differences. The hyperacute rejection process is primarily due to the attachment of preformed xenoreactive antibodies to the donor vascular endothelium, which results in hyperactivation of the complement system beyond the control of the natural complement regulatory proteins. Understanding the complex and diverse immune components involved in hyperacute, acute, and accelerated rejections has resulted in the development of different hematologic and molecular strategies. Plasmapheresis has been used to remove xenoantibodies, and xenoperfusion techniques are used to create a suitable and familiar environment for the xenograft. Various molecular approaches, such as the development of transgenic animals expressing human complement regulatory proteins such as CD59 or decay accelerating factor (DAF), to downregulate complement activation or the production of pigs lacking the xenoreactive antigen by knockout of the Galα‐1,3‐galactosyl transferase gene have also been attempted. A combination of these techniques together with the administration of soluble complement inhibitors such as the vaccinia virus complement control protein (VCP) may well contribute to prolong graft survival. However, various issues including the possible emergence of new viral infections have confounded the topic of xenotransplantation. Here the different modulatory approaches and agents mediating interventions in xenorejection are discussed.
In Vitro Mutagenicity Studies of the Antiretrovirals AZT, Didanosine, and 3TC and a Plant Antiviral Extract Secomet‐V Derived from the Trifollium Species
Authors: BALLARDIN MICHELA , SCARPATO ROBERTO , KOTWAL GIRISH J. , BARALE ROBERTO
Published: December 2005

The plant extract Secomet‐V has previously been shown by Kotwal et al. to have potent antiviral activity. It was tested for mutagenecity with the Ames gene mutation test in Salmonella and the chromosome damage (clastogenic) micronucleolus (MN) test in human lymphocytes. These tests predict long‐term carcinogenesis activity of the agents tested. Secomet‐V (with charcoal added) demonstrated weak clastogenic activity, but powerful mutagenic activity in the Ames test with the addition of exogenous metabolic activation. The mutagenic activity of the conventional antiretroviral drugs AZT, Didanosine (DID), and 3TC alone and in dual combinations was also assessed for the first time for Salmonella mutagenicity without any mutagenic effects. AZT, DID, and 3TC have also been tested for MN induction; DID and 3TC resulted negatively, whereas AZT was positive in a dose‐related manner. The dual combinations of AZT and DID, 3TC and DID plus 3TC did not result in any additive or synergistic effect. Purification in the absence of charcoal results in a drastic reduction in extract mutagenicity, which is almost reduced completely by further ultrafiltration (cutoff <3,000 Da). This fraction, which is a mixture of molecules of less than 3,000 Da, still possesses the capability to induce sister chromatid exchanges in human lymphocytes. This could be due to residual mutagenicity or, more likely, to the slowdown of the DNA replication process. These findings open new possibilities for HIV therapy, because this antiviral activity of Secomet‐V purified in the absence of charcoal and further filtered through a 3,000‐Da filter is devoid of mutagenic activity and therefore safe for long‐term use.
Novel Bacterial Delivery System with Attenuated Salmonella typhimurium Carrying Plasmid Encoding Mtb Antigen 85A for Mucosal Immunization: Establishment of Proof of Principle in TB Mouse Model
Authors: PARIDA SHREEMANTA K. , HUYGEN KRIS , RYFFEL BERNHARD , CHAKRABORTY TRINAD
Published: December 2005

Tuberculosis (TB), the leading killer of young adults worldwide, newly affects one person every second and kills one in every 15 seconds. The recent increase of TB in developing countries has been exacerbated by many causes including pandemic HIV, war and political instability, drug resistance, and increasing poverty. Genetic immunization has emerged with tremendous potential in vaccination against TB with success in animal models with naked DNA encoding different genes such as Ag85A, Pst3, and hsp65. However, there are shortcomings in translating this success into reality in human clinical trials due to limitations at the level of delivery, quality, and quantity of DNA to be administered, which can be circumvented by using an attenuated bacteria delivery system for transgene vaccination for mucosal immunization targeting the inductive sites of the immune system. We compare this novel delivery system using an attenuated Salmonella ΔaroA strain through a mucosal route with classic intramuscular DNA delivery using a potential protective antigen, Ag85A, of Mycobacterium tuberculosis in a mouse infection virulent challenge model. We show an immune response and superior protection in the mice at the level of the lungs as well as the spleen against a virulent challenge after intranasal immunization by recombinant Salmonella typhimurium carrying a eukaryotic expression plasmid encoding Ag85A rather than the classic DNA immunization and at par with the protection conferred by BCG. This study establishes the proof of principle of this system for further exploitation of this platform for vaccine development, which is being pursued for postexposure vaccine development for TB.
Antiesophageal Cancer Activity from Southern African Marine Organisms
Authors: WHIBLEY CATHERINE E. , KEYZERS ROBERT A. , SOPER ANDREW G. , DAVIES‐COLEMAN MICHAEL T. , SAMAAI TOUFIEK , HENDRICKS DENVER T.
Published: December 2005

Squamous cell esophageal cancer presents a significant health burden in many developing countries around the world. In South Africa, this disease is one of the most common causes of cancer‐related deaths in black males. Because this cancer is only modestly responsive to available chemotherapeutic agents, there is a need to develop more effective therapeutic agents for this cancer. Marine organisms are currently regarded as a promising source of unique bioactive molecules because they display a rich diversity of secondary metabolites. Some of these compounds have significant anticancer activity, with a few of these currently in phase I and II clinical trials. We report here an ongoing program to screen marine organisms collected from subtidal benthic communities off the coast of southern Africa for activity against cultured esophageal cancer cells. Of the 137 extracts tested, 2.2% displayed high activity (score = 3) and 11.7% displayed moderate activity (score = 2) against cultured esophageal cancer cells. Our results suggest that sponges had a higher hit rate (21.9%) than ascidians (7.1%). Using activity‐directed purification, seven previously described compounds and four novel compounds, with varying activity against esophageal cancer cell lines, were isolated from the sponges Axinella weltneri, Aplysilla sulphurea, and Strongylodesma aliwaliensis. The results of this study suggest that subtidal benthic marine organisms collected off the coast of southern Africa hold potential for identifying possible drug leads for the development of agents with activity against esophageal cancer.
Hemolytic Uremic Syndrome: An Example of Insufficient Complement Regulation on Self‐Tissue
Authors: ATKINSON JOHN P. , LISZEWSKI M KATHRYN , RICHARDS ANNA , KAVANAGH DAVID , MOULTON ELIZABETH A.
Published: December 2005

Hemolytic uremic syndrome (HUS) is a triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. HUS is classified as either diarrhea associated, most commonly caused by infection with Escherichia coli O157, or the less common atypical HUS (aHUS), which may be familial or sporadic. Approximately 50% of patients with aHUS have mutations in one of the complement control proteins: factor H, factor I, or membrane cofactor protein (MCP). These proteins regulate complement activation through cofactor activity, the inactivation of C3b by limited proteolytic cleavage, a desirable event in the fluid phase (no target) or on healthy self‐tissue (wrong target). Complement activation follows the endothelial cell injury that characterizes HUS. This disease represents a model of what takes place when inappropriate complement activation occurs on self‐tissues due to the presence of mutated complement regulatory proteins. Screening for mutations in factor H, factor I, or MCP is expensive and time consuming. One approach is to perform antigenic screening for factor H and factor I deficiency and to look for low levels of MCP (CD46) expression by flow cytometry. Complement regulatory protein deficiency impacts treatment decisions as patients with aHUS have a recurrence rate in renal transplants of ∼50%, whereas those with factor H mutations have an even higher risk (∼80%). By contrast, MCP deficiency can be corrected in part by a renal allograft. However, caution in the use of live‐related donations is needed because of the high rates of incomplete penetrance of the described mutations.
Opportunities for New Therapies Based on the Natural Regulators of Complement Activation
Authors: BROOK EVE , HERBERT ANDREW P. , JENKINS HUW T. , SOARES DINESH C. , BARLOW PAUL N.
Published: December 2005

While the complement system is an essential component of immunity, shutting down all or part of it could be beneficial in a wide range of clinical situations. Designer, small‐molecule, protease inhibitors and antagonists of protein‐protein interactions are under development, while an approach based on a humanized monoclonal antibody to the C5 component works effectively against the later stages of complement activation and is close to completing clinical trials. The cobra venom factor depletes plasma of essential complement components, and a humanized (nonimmunogenic) version is being sought. Perhaps the most promising approach to comprehensive complement downregulation, however, is the exploitation of innate regulators of complement activation, with two products in clinical trials. The potential for more efficacious complement blockers of this kind is growing because of better targeting, but a deeper knowledge at the atomic level of mechanisms of action of these regulators is needed to underpin a rational approach to design of still more potent complement inhibitors.
Histamine Scavenging Attenuates Endotoxin‐Induced Acute Lung Injury
Authors: RYFFEL BERNHARD , COUILLIN ISABELLE , MAILLET ISABELLE , SCHNYDER BRUNO , PAESEN GUIDO C. , NUTTALL PATRICIA , WESTON‐DAVIES WYNNE
Published: December 2005

Histamine is an important mediator of early and late inflammatory responses. Here we asked whether scavenging of endogenous histamine by the arthropod‐derived histamine binding protein EV131 diminishes acute respiratory distress syndrome (ARDS) induced by inhaled endotoxin. We demonstrate that EV131 (360 μg given intranasally) reduced endotoxin‐induced bronchoconstriction and recruitment of neutrophils. Furthermore, EV131 administration diminished TNF‐α and protein leak in the bronchoalveolar lavage fluid. The data suggest that histamine attenuates endotoxin‐induced bronchoconstriction and neutrophil recruitment. Therefore, scavenging of histamine by EV131 may represent a novel therapeutic strategy in ARDS.
Development of Domain‐Selective Angiotensin I‐Converting Enzyme Inhibitors
Authors: REDELINGHUYS PIERRE , NCHINDA ALOYSIUS T. , STURROCK EDWARD D.
Published: December 2005

Somatic angiotensin‐converting enzyme (ACE) is an essential component of the renin‐angiotensin system and consequently plays a key role in blood pressure and electrolyte homeostasis. Thus, ACE inhibitors are widely used in the treatment of cardiovascular disease, causing a decrease in the production of angiotensin II and an increase in the circulating vasodilator bradykinin. The ectodomain of ACE consists of two parts (N and C domains), each bearing an active site that differs in substrate and inhibitor specificity. Advances in the elucidation of the functional roles of these two domains and an expanded view of the renin‐angiotensin system underscore the need for the next generation of domain‐selective inhibitors with improved pharmacologic profiles. Moreover, recent breakthroughs in determining the crystal structure of testis ACE (identical to the C domain) and its homologue ACE2 provide new mechanistic insights into the interactions of ACE inhibitors and substrates with active site pockets. This review summarizes the structural basis and recent synthetic chemistry approaches to the development of novel domain‐selective inhibitors.
ProtEx™: A Novel Technology to Display Exogenous Proteins on the Cell Surface for Immunomodulation
Authors: SINGH NARENDRA P. , YOLCU ESMA S. , ASKENASY NADIR , SHIRWAN HAVAL
Published: December 2005

Gene therapy as an immunomodulatory approach has the potential to treat various inherited and acquired immune‐based human diseases. However, its clinical application has several challenges, varying from the efficiency of gene transfer, control of gene expression, cell and tissue targeting, and safety concerns associated with the introduction of exogenous DNA into cells/tissues. Gene therapy is also a time‐ and labor‐intensive procedure. As an alternative, we recently developed a novel technology, ProtEx™, that allows for rapid, efficient, and durable display of exogenous proteins on the surface of cells, tissues, and organs without detectable toxicity. This technology exploits the strong binding affinity (Kd= 10−15M) of streptavidin with biotin and involves generation of chimeric molecules composed of the extracellular portions of immunological proteins of interest and a modified form of streptavidin, biotinylation of biological surfaces, and decoration of the modified surface with chimeric proteins. Biotin persists on the cell surface for weeks both in vitro and in vivo, thereby providing a platform to display exogenous proteins with extended cell surface kinetics. Two chimeric proteins, rat FasL (SA‐FasL) and human CD80 (CD80‐SA), were generated and tested for cell surface display and immunomodulatory functions. SA‐FasL and CD80‐SA molecules persisted on the surface of various cell types for extended periods, varying from days to weeks in vitro and in vivo. The cell surface kinetics, however, were protein and cell type dependent. SA‐FasL showed potent apoptotic activity against Fas+ cells as a soluble protein or displayed on the cell surface and effectively blocked alloreactive responses. The display of CD80‐SA on the surface of tumor cells, however, converted them into antigen‐presenting cells for effective stimulation of autologous and allogeneic T‐cell responses. ProtEx technology, therefore, represents a practical and effective alternative to DNA‐based gene therapy for immunomodulation.
Parasite Mitochondria as a Target of Chemotherapy: Inhibitory Effect of Licochalcone A on the Plasmodium falciparum Respiratory Chain
Authors: MI‐ICHI FUMIKA , MIYADERA HIROKO , KOBAYASHI TAMAKI , TAKAMIYA SHINZABURO , WAKI SEIJI , IWATA SUSUMU , SHIBATA SHOJI , KITA KIYOSHI
Published: December 2005

Parasites have exploited unique energy metabolic pathways as adaptations to the natural host habitat. In fact, the respiratory systems of parasites typically show greater diversity in electron transfer pathways than do those of host animals. These unique aspects of parasite mitochondria and related enzymes may represent promising targets for chemotherapy. Natural products have been recognized as a source of the candidates of the specific inhibitors for such parasite respiratory chains. Chalcones was recently evaluated for its antimalarial activity in vitro and in vivo. However, its target is still unclear in malaria parasites. In this study, we investigated that licochalcone A inhibited the bc1 complex (ubiquinol‐cytochrome c reductase) as well as complex II (succinate ubiquinone reductase, SQR) of Plasmodium falciparum mitochondria. In particular, licochalcone A inhibits bc1 complex activity at very low concentrations. Because the property of the P. falciparum bc1 complex is different from that of the mammalian host, chalcones would be a promising candidate for a new antimalarial drug.
Effect of Rhythmic Breathing (Sudarshan Kriya and Pranayam) on Immune Functions and Tobacco Addiction
Authors: KOCHUPILLAI VINOD , KUMAR PRATIK , SINGH DEVINDER , AGGARWAL DHIRAJ , BHARDWAJ NARENDRA , BHUTANI MANISHA , DAS SATYA N.
Published: December 2005

Stress, a psychophysiological process, acts through the immune‐neuroendocrine axis and affects cellular processes of body and immune functions, leading to disease states including cancer. Stress is also linked to the habit of tobacco consumption and substance abuse, which in turn also leads to diseases. Sudarshan Kriya (SK) and Pranayam (P), rhythmic breathing processes, are known to reduce stress and improve immune functions. Cancer patients who had completed their standard therapy were studied. SK and P increased natural killer (NK) cells significantly (P <0.001) at 12 and 24 weeks of the practice compared to baseline. Increase in NK cells at 24 weeks was significant (P <0.05) compared to controls. There was no effect on T‐cell subsets after SK and P either in the study group or among controls. SK and P helped to control the tobacco habit in 21% of individuals who were followed up to 6 months of practice. We conclude that the inexpensive and easy to learn and practice breathing processes (SK and P) in this study demonstrated an increase in NK cells and a reduction in tobacco consumption. When confirmed in large and randomized studies, this result could mean that the regular practice of SK and P might reduce the incidence and progression of cancer.
Low Level Laser Therapy (LLLT) as an Effective Therapeutic Modality for Delayed Wound Healing
Authors: HAWKINS D , HOURELD N , ABRAHAMSE H
Published: December 2005

Low level laser therapy (LLLT) is a form of phototherapy that involves the application of low power monochromatic and coherent light to injuries and lesions. It has been used successfully to induce wound healing in nonhealing defects.1 Other wounds treated with lasers include burns, amputation injuries, skin grafts, infected wounds, and trapping injuries.2 The unique properties of lasers create an enormous potential for specific therapy of skin diseases. As with any new device, the most efficacious and appropriate use requires an understanding of the mechanisms of light interaction with tissue as well as the properties of the laser itself.3
In Vivo Potentialities of EWS‐Fli‐1 Targeted Antisense Oligonucleotides‐Nanospheres Complexes
Authors: MAKSIMENKO ANDREI , POLARD VALERIE , VILLEMEUR MARIE , ELHAMESS HIND , COUVREUR PATRICK , BERTRAND JEAN‐REMI , ABOUBAKAR MALAM , GOTTIKH MARINA , MALVY CLAUDE
Published: January 2006

The EWS/FLI‐1 fusion gene, resulting from a t(11;22) translocation, plays a key role in the pathogenesis of Ewing sarcoma. Previously, we have shown that antisense oligonucleotides designed against EWS‐Fli‐1 inhibited tumor growth in nude mice provided they were delivered intratumorally by nanocapsules or by CTAB‐coated nanospheres. In this study, we have used two types of nanospheres (designated as type 1 and type 2 nanospheres) stabilized with chitosan for both intratumoral and systemic administration of oligonucleotides. Inhibition of the tumor growth in vivo was found to be dependent on the carrier type as well as on antisense oligonucleotide modification. Indeed, whereas both types of nanospheres were efficient in reducing tumor growth after intratumoral injection, we have obtained only with type 2 nanospheres an antitumoral effect after intravenous injection in a preliminary experiment. Additionally, the anticancer efficacy of a localized modification of the EWS‐Fli‐1 phosphodiester/phosphorothioate chimeric antisense oligonucleotide was demonstrated. In cell culture the oligonucleotides inhibit cell growth by their antisense activity. Further investigations are needed in vivo to learn the mechanism of action of the complexes.