Raghavan Raju

Georgia Regents University, Augusta, Georgia, United States

Are you Raghavan Raju?

Claim your profile

Publications (38)163.5 Total impact

  • Ahmar Ayub, Ninu Poulose, Raghavan Raju
    [Show abstract] [Hide abstract]
    ABSTRACT: Resveratrol has been shown to potentiate mitochondrial function and extend longevity, however there is no evidence showing whether resveratrol can improve survival or prolong life following hemorrhagic shock. In this report we sought to determine whether (a) resveratrol can improve survival following hemorrhage and resuscitation and (b) prolong life in the absence of resuscitation. Using a hemorrhagic injury (HI) model in the rat, we describe for the first time that the naturally occurring small molecule, resveratrol, may be an effective adjunct to resuscitation fluid. In a series of three sets of experiments we show that resveratrol administration during resuscitation improves survival following HI (p<0.05), resveratrol and its synthetic mimic SRT1720 can significantly prolong life in the absence of resuscitation fluid (<30 min vs up to 4 hr; p<0.05), and resveratrol as well as SRT1720 restores left ventricular function following HI. We also found significant changes in the expression level of mitochondria-related transcription factors Ppar-α and Tfam, as well as Pgc-1α in the left ventricular tissues of rats subjected to HI and treated with resveratrol. The results indicate that resveratrol is a strong candidate adjunct to resuscitation following severe hemorrhage.
    Molecular Medicine 04/2015; DOI:10.2119/molmed.2015.00013 · 4.82 Impact Factor
  • Ninu Poulose, Raghavan Raju
    [Show abstract] [Hide abstract]
    ABSTRACT: Aging is characterized by increased oxidative stress, heightened inflammatory response, accelerated cellular senescence and progressive organ dysfunction. The homeostatic imbalance with aging significantly alters cellular responses to injury. Though it is unclear whether cellular energetic imbalance is a cause or effect of the aging process, preservation of mitochondrial function has been reported to be important in organ function restoration following severe injury. Unintentional injuries are ranked among the top 10 causes of death in adults of both sexes, 65 years and older. Aging associated decline in mitochondrial function has been shown to enhance the vulnerability of heart, lung, liver and kidney to ischemia/reperfusion injury. Studies have identified alterations in the level or activity of factors such as SIRT1, PGC-1α, HIF-1α and c-MYC involved in key regulatory processes in the maintenance of mitochondrial structural integrity, biogenesis and function. Studies using experimental models of hemorrhagic injury and burn have demonstrated significant influence of aging in metabolic regulation and organ function. Understanding the age-associated molecular mechanisms regulating mitochondrial dysfunction following injury is important towards identifying novel targets and therapeutic strategies to improve the outcome after injury in the elderly.
    04/2014; 5(2):101-108. DOI:10.14336/AD.2014.0500101
  • [Show abstract] [Hide abstract]
    ABSTRACT: Age-related macular degeneration (AMD) is a sight threating retinal eye disease that affects millions of aging individuals world-wide. Choroid-retinal pigment epithelium (RPE)-neuroretina axis in the posterior compartment of the eye is the primary site of AMD pathology. There are compelling evidence to indicate association of vascular endothelial growth factors (VEGF) to AMD. Here, we report the inhibitory actions of resveratrol (RSV) on inflammatory cytokine, TGF-β and hypoxia induced VEGF secretion by human retinal pigment epithelial cells (HRPE). HRPE cultures prepared from aged human donor eyes were used for the studies in this report. HRPE secreted both VEGF-A and VEGF-C in small quantities constitutively. Stimulation with a mixture of inflammatory cytokines (IFN-γ, TNF-α, IL-1β), significantly increased the secretion of both VEGF-A and VEGF-C. RSV, in a dose dependent (10-50 uM) manner, suppressed VEGF-A and VEGF-C secretion induced by inflammatory cytokines significantly. RT-PCR analysis indicated that effects of RSV on VEGF secretion were possibly due to decreased mRNA levels. TGF-β and cobalt chloride (hypoxia mimic) also upregulated HRPE cell production of VEGF-A, and this was inhibited by RSV. In contrast, RSV had no effect on anti-angiogenic molecules, endostatin and pigment epithelial derived factor secretion. Studies using an in vitro scratch assay revealed that wound closure was also inhibited by RSV. These results demonstrate that RSV can suppress VEGF secretion induced by inflammatory cytokines, TGF-β and hypoxia. Under pathological conditions, over expression of VEGF is known to worsen AMD. Therefore, RSV may be useful as nutraceutical in controlling pathological choroidal neovascularization processes in AMD.
    04/2014; 5(2):88-100. DOI:10.14366/AD.2014.050088
  • [Show abstract] [Hide abstract]
    ABSTRACT: Severe hemorrhage leads to decreased blood flow to tissues resulting in decreased oxygen and nutrient availability affecting mitochondrial function. A mitoscriptome profiling study demonstrated alteration in several genes related to mitochondria, consistent with the mitochondrial functional decline observed following trauma-hemorrhage (T-H). Our experiments led to the identification of sirtuin (SIRT)1 as a potential target in T-H. Administration of resveratrol, a naturally occurring polyphenol and activator of SIRT1, following T-H improved left ventricular function and tissue ATP levels. Our hypothesis was that mitochondrial function following T-H is dependent on SIRT1 activity. In this study, we evaluated the activity of SIRT1, a mitochondrial functional modulator, and the mitochondrial-glycolytic balance following T-H. We determined the changes in protein levels of pyruvate dehydrogenase kinase (PDK)1 and nuclear c-Myc, PGC-1α and NRF2 following T-H and after treatment with resveratrol or a combination of sirtinol (a SIRT1 inhibitor) and resveratrol. We have also tested the activity of mitochondrial complex 1. SIRT1 enzyme activity was significantly decreased following T-H whereas resveratrol treatment restored the activity. We found elevated PDK1 and c-Myc levels and decreased PGC-1α, NRF2 and mitochondrial complex I activity following T-H. The reduced SIRT1 activity after T-H may be related to declined mitochondrial function as resveratrol was able to reinstate SIRT1 activity and mitochondrial function. The elevated level of PDK1, an inhibitor of pyruvate dehydrogenase complex, following T-H indicates a possible shift in cellular energetics from mitochondria to glycolysis. In conclusion, SIRT1 modulation alters left ventricular function following T-H through regulation of cellular energetics.
    Molecular Medicine 12/2013; DOI:10.2119/molmed.2013.00077 · 4.82 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In a microarray analysis of human retinal pigment epithelial cells (HRPE) treated with TGF-β, in addition to the alteration of a number of known Extracellular matrix (ECM)-related genes regulated by TGF-β, we found a significant increase in the expression of Kallmann Syndrome (KAL)-1 gene, that codes for the protein anosmin-1. Enhanced expression of KAL-1 by TGF-β was validated by real-time PCR analysis. In in vitro experiments, TGF-β receptor inhibitor abolished TGF-β-induced expression of KAL-1. Immunofluorescence staining showed increased presence of anosmin-1 in TGF-β treated HRPE cells, with distinct localization at the intercellular junctions. Treatment of HRPE cells with TGF-β enhanced secretion of anosmin-1 and the release of anosmin-1 was further augmented by heparin sulfate. Enhanced secretion of anosmin-1 in the presence of TGF-β and heparin was also observed in other ocular cells such as corneal epithelial and corneal fibroblast cultures. The role of anosmin-1, a protein with adhesion functions, in retinal structure, function and pathology has not been known and remains to be investigated.
    Cytokine 01/2013; 61(3). DOI:10.1016/j.cyto.2012.12.019 · 2.87 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose: Human immunodeficiency virus (HIV)-related fatigue (HRF) is multicausal and potentially related to mitochondrial dysfunction caused by antiretroviral therapy with nucleoside reverse transcriptase inhibitors (NRTIs). Methodology: The authors compared gene expression profiles of CD14+ cells of low versus high fatigued, NRTI-treated HIV patients to healthy controls (n = 5/group). The authors identified 32 genes predictive of low versus high fatigue and 33 genes predictive of healthy versus HIV infection. The authors constructed genetic networks to further elucidate the possible biological pathways in which these genes are involved. Relevance for nursing practice: Genes including the actin cytoskeletal regulatory proteins Prokineticin 2 and Cofilin 2 along with mitochondrial inner membrane proteins are involved in multiple pathways and were predictors of fatigue status. Previously identified inflammatory and signaling genes were predictive of HIV status, clearly confirming our results and suggesting a possible further connection between mitochondrial function and HIV. Isolated CD14+ cells are easily accessible cells that could be used for further study of the connection between fatigue and mitochondrial function of HIV patients. Implication for Practice: The findings from this pilot study take us one step closer to identifying biomarker targets for fatigue status and mitochondrial dysfunction. Specific biomarkers will be pertinent to the development of methodologies to diagnosis, monitor, and treat fatigue and mitochondrial dysfunction.
    Biological Research for Nursing 01/2013; 15(2). DOI:10.1177/1099800411421957 · 1.34 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: OBJECTIVE: In sporadic inclusion body myositis (sIBM), inflammation and accumulation of β- amyloid-associated molecules cause muscle fiber damage. Intravenous immunoglobulin (IVIG) and prednisone are effective in other inflammatory myopathies, but, for reasons unknown, not in sIBM. METHODS: Relevant inflammatory and degeneration-associated markers were assessed by quantitative-PCR and immunohistochemistry in repeated muscle biopsies from sIBM patients treated in a controlled study with IVIG and prednisone or prednisone alone (each n=5). Functional effects were assessed in a muscle cell-culture model. RESULTS: In muscle biopsies, the mRNA-expression of the pro-inflammatory chemokines CXCL-9, CCL-3, and CCL-4, and the cytokines IFN-γ, TGF-β, IL-10, and IL-1β was significantly reduced after treatment in both groups. No consistent changes were observed for TNF-α, IL-6, ICOS-L, ICOS, and perforin. The degeneration-associated molecule ubiquitin and the heat-shock-protein αB-crystallin were also reduced, but no changes were noted for amyloid-precursor-protein (APP) or desmin. By immunohistochemistry, a significant downmodulation of chemokines but not of iNOS, nitrotyrosine, IL-1β, APP, and ubiquitin was observed, and β-amyloid was reduced in 6 of 10 patients. Pronounced staining of IgG was observed in the muscle after IVIG, indicating penetration of infused IgG into the muscle and a possible local effect. In muscle cells exposed to IFN-γ+IL-1β, IgG and/or prednisone downregulated the mRNA-expression of IL-1β by 2.5-fold. Accumulation of β-amyloid, overexpression of αB-crystallin and cell-death was prevented. By contrast, nitric-oxide (NO)- associated cell-stress remained unchanged. CONCLUSIONS: IVIG and prednisone reduce some inflammatory and degenerative molecules in sIBM muscle and in vitro, but do not sufficiently suppress myotoxic and cell-stress mediators such as NO. The data provide an explanation for the resistance of sIBM to immunotherapy and identify markers that may help to design novel treatment strategies. © 2012 American College of Rheumatology.
    Arthritis & Rheumatology 12/2012; 64(12). DOI:10.1002/art.37692 · 7.87 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Mitochondria play a critical role in metabolic homeostasis of a cell. Our recent studies, based on the reported interrelationship between c-Myc and Sirt1 (mammalian orthologue of yeast sir2 [silent information regulator 2]) expression and their role in mitochondrial biogenesis and function, demonstrated a significant downregulation of Sirt1 protein expression and an upregulation of c-Myc following trauma-hemorrhage (T-H). Activators of Sirt1 are known to improve mitochondrial function and the naturally occurring polyphenol resveratrol (RSV) has been shown to significantly increase Sirt1 activity by increasing its affinity to both NAD+ and the acetylated substrate. In this study we tested the salutary effect of RSV following T-H and its influence on Sirt1 expression. Rats were subjected to T-H or sham operation. RSV (8 mg/kg body weight, intravenously) or vehicle was administered 10 min after the onset of resuscitation, and the rats were killed 2 h following resuscitation. Sirtinol, a Sirt1 inhibitor, was administered 5 min prior to RSV administration. Cardiac contractility (±dP/dt) was measured and heart tissue was tested for Sirt1, Pgc-1α, c-Myc, cytosolic cytochrome C expression and ATP level. Left ventricular function, after T-H, was improved (P < 0.05) following RSV treatment, with significantly elevated expression of Sirt1 (P < 0.05) and Pgc-1α (P < 0.05), and decreased c-Myc (P < 0.05). We also observed significantly higher cardiac ATP content, declined cytosolic cytochrome C and decreased plasma tumor necrosis factor-α in the T-H-RSV group. The salutary effect due to RSV was abolished by sirtinol, indicating a Sirt1-mediated effect. We conclude that RSV may be a useful adjunct to resuscitation fluid following T-H.
    Molecular Medicine 11/2011; 18(1):209-14. DOI:10.2119/molmed.2011.00365 · 4.82 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose. In limited samples of valuable biological tissues, univariate ranking methods of microarray analyses often fail to show significant differences among expression profiles. In order to allow for hypothesis generation, novel statistical modeling systems can be greatly beneficial. The authors applied new statistical approaches to solve the issue of limited experimental data to generate new hypotheses in CD14(+) cells of patients with HIV-related fatigue (HRF) and healthy controls. Methodology. We compared gene expression profiles of CD14(+) cells of nucleoside reverse transcriptase inhibitor (NRTI)-treated HIV patients with low versus high fatigue to healthy controls (n = 5 each). With novel Bayesian modeling procedures, the authors identified 32 genes predictive of low versus high fatigue and 33 genes predictive of healthy versus HIV infection. Sparse association and liquid association networks further elucidated the possible biological pathways in which these genes are involved. Relevance for nursing practice. Genetic networks developed in a comprehensive Bayesian framework from small sample sizes allow nursing researchers to design future research approaches to address such issues as HRF. Implication for practice. The findings from this pilot study may take us one step closer to the development of useful biomarker targets for fatigue status. Specific and reliable tests are needed to diagnosis, monitor and treat fatigue and mitochondrial dysfunction.
    Biological Research for Nursing 11/2011; 15(2). DOI:10.1177/1099800411423307 · 1.34 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Trauma-hemorrhage (T-H) causes hypoxia and organ dysfunction. Mitochondrial dysfunction is a major factor for cellular injury due to T-H. Aging also has been known to cause progressive mitochondrial dysfunction. In order to study the effect of aging on T-H-induced mitochondrial dysfunction, we recently developed a rodent mitochondrial genechip with probesets representing mitochondrial and nuclear genes contributing to mitochondrial structure and function. Using this chip we recently identified signature mitochondrial genes altered following T-H in 6 and 22 month old rats; augmented expression of the transcription factor c-myc was the most pronounced. Based on reports of c-myc-IL6 collaboration and c-myc-Sirt1 negative regulation, we further investigated the expression of these regulatory factors with respect to aging and injury. Rats of ages 6 and 22 months were subjected to T-H or sham operation and left ventricular tissues were tested for cytosolic cytochrome c, mtDNA content, Sirt1 and mitochondrial biogenesis factors Foxo1, Ppara and Nrf-1. We observed increased cardiac cytosolic cytochrome c (sham vs T-H, p<0.03), decreased mitochondrial DNA content (sham vs T-H, p<0.05), and decreased Sirt1 expression (sham vs TH, p<0.05) following T-H and with progressing age. Additionally, expression of mitochondrial biogenesis regulating transcription factors Foxo1 and Nrf-1 was also decreased with T-H and aging. Based upon these observations we conclude that Sirt1 expression is negatively modulated by T-H causing downregulation of mitochondrial biogenesis. Thus, induction of Sirt1 is likely to produce salutary effects following T-H induced injury and hence, Sirt1 may be a potential molecular target for translational research in injury resolution.
    Biochimica et Biophysica Acta 04/2011; 1812(11):1446-51. DOI:10.1016/j.bbadis.2011.04.010 · 4.66 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Mitochondria are the major sites where energy is produced in the cell. Functions of organs such as the heart which has high energy demand are seriously affected by dysfunction of mitochondria. The functional changes in energy-dependent organs such as heart due to aging or any other cause are expected to be reflected in changes in expression of genes related to mitochondrial structure and function. Conversely, alteration of mitochondrial gene expression by any reason may also adversely affect function of organs such as heart that are energy-dependent. Molecular profiling of mitochondrial gene expression is therefore critical to understanding the mechanism of organ dysfunction. Mitochondrial structure and function are controlled by genes in the nuclear DNA and those in the mitochondrial DNA (mtDNA). The transcriptome from these two sources, together, contributing to the structure and function of mitochondria may be called mitoscriptome. This review elaborates on data gathered using a gene chip, RoMitochip, developed in our laboratory to study mitochondrial functional alteration in cardiomyocytes and left ventricular tissue following hypoxia or hemorrhagic injury. RoMitochip consists of probesets representing genes from nuclear DNA and mtDNA of both mice and rats. Our experiments using this chip in in vitro model of hypoxia and in vivo hemorrhagic injury model determined mitoscriptome signatures following hypoxia and hemorrhage, respectively. In addition, we also discuss past initiatives from other investigators that led to the development of microarray tools to profile mitoscriptome.
    04/2011; 2(2):174-180.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Cardiac dysfunction and mortality associated with trauma and sepsis increase with age. Mitochondria play a critical role in the energy demand of cardiac muscles, and thereby on the function of the heart. Specific molecular pathways responsible for mitochondrial functional alterations after injury in relation to aging are largely unknown. To further investigate this, 6- and 22-month-old rats were subjected to trauma-hemorrhage (T-H) or sham operation and euthanized following resuscitation. Left ventricular tissue was profiled using our custom rodent mitochondrial gene chip (RoMitochip). Our experiments demonstrated a declined left ventricular performance and decreased alteration in mitochondrial gene expression with age following T-H and we have identified c-Myc, a pleotropic transcription factor, to be the most upregulated gene in 6- and 22-month-old rats after T-H. Following T-H, while 142 probe sets were altered significantly (39 up and 103 down) in 6-month-old rats, only 66 were altered (30 up and 36 down) in 22-month-old rats; 36 probe sets (11 up and 25 down) showed the same trend in both groups. The expression of c-Myc and cardiac death promoting gene Bnip3 were increased, and Pgc1-α and Ppar-α a decreased following T-H. Eleven tRNA transcripts on mtDNA were upregulated following T-H in the aged animals, compared with the sham group. Our observations suggest a c-myc-regulated mitochondrial dysfunction following T-H injury and marked decrease in age-dependent changes in the transcriptional profile of mitochondrial genes following T-H, possibly indicating cellular senescence. To our knowledge, this is the first report on mitochondrial gene expression profile following T-H in relation to aging.
    Molecular Medicine 12/2010; 17(5-6):542-9. DOI:10.2119/molmed.2010.00195 · 4.82 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Purposes/Aims: The purpose of this study was to examine the relationship between fatigue and genomic expression markers of mitochondrial dysfunction. Rationale/Conceptual Basis/Background: HIV-related fatigue is multi-causal in origin and potentially related to mitochondrial dysfunction caused by nucleoside reverse transcriptase inhibitors (NRTIs). CD14+ cells are undifferentiated macrophages, vulnerable to HIV infection, and easily accessible for gene expression experiments in a purified cell population. Identification of genes that will let us develop biomarkers for fatigue will aid developing diagnostic and progression measures. Methods: We utilized a novel mitochondrially-specific gene expression microarray to assess mitochondrial and nuclear genes in CD14+ cells of low and high fatigued HIV/AIDS patients (n=5 each). Results: Novel Bayesian and liquid association network methods identified 33 genes predictive of low versus high fatigue and 32 genes predictive of healthy versus HIV infection. SULT2B1, a gene in the sulfotransferase family is relevant to both the cholesterol and testosterone pathway and like identified inner mitochondrial membrane genes predictive of fatigue status while outer mitochondrial membrane genes were predictive of HIV status. A surprising finding was that adenylate cyclase 2 (ADCY2) was a predictor of both HIV and fatigue, it had the highest Kendall’sTau association value in the HIV group but in reverse the lowest Tau value in the fatigue group. Implications: Isolating CD14+ cells may provide an alternative to muscle biopsy and a minimally invasive way to study patient mitochondrial function, and Bayesian and network tools are useful to identify the link between subjective symptom perceptions and underlying biologically pathways. Fatigue status in HIV patients treated with NRTIs is linked to RNA expression related mitochondrial function. Additional studies are needed to confirm the relevance of our findings in other tissues (e. g. skeletal muscle) and to understand the significance of key genes such as SULT2B and ADCY2 in fatigue and HIV disease.
    2011 Western Institute of Nursing Annual Communicating Nursing Research Conference; 04/2010
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Trauma-hemorrhage (T-H) is known to impair tissue perfusion, leading to tissue hypoxia, and thus affecting mitochondria, the organelles with the highest oxygen demand. In a model of T-H and prolonged hypotension without fluid resuscitation, administration of a small volume of 17beta-estradiol (E2), but not vehicle, prolonged the survival of rats for 3 h, even in the absence of fluid resuscitation. The main finding of this study is that T-H followed by prolonged hypotension significantly affects mitochondrial function, endoplasmic reticulum (ER) stress markers and free iron levels, and that E2 ameliorated all these changes. All of these changes were observed in the liver but not in the kidney. The sensitivity of mitochondrial respiration to exogenous cytochrome c can reflect increased permeability of the outer mitochondrial membrane for cytochrome c. Increased levels of free iron are indicative of oxidative stress, but neither oxidative nor nitrosylative stress markers changed. The spliced isoform of XBP1 mRNA (an early marker of ER stress) and the expression of C/EBP homologous protein (CHOP) (a protein regulating ER stress-induced apoptosis) were elevated in T-H animals but remained unchanged if T-H rats received E2. Both the prevention of elevated sensitivity of mitochondrial respiration to cytochrome c and a decrease in ER stress by E2 maintain functional integrity of the liver and may help the organ during prolonged hypotension and following resuscitation. A decrease in free iron levels by E2 is more relevant for resuscitation, often accompanied by oxidative stress reaction. Thus, E2 appears to be a novel hormonal adjunct that prolongs permissive hypotension during lengthy transportation of the injured patient between the injury site and the hospital in both civilian and military injuries.
    Molecular Medicine 03/2010; 16(7-8):254-61. DOI:10.2119/molmed.2009.00184 · 4.82 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The hypoxic conditions induced by reduced blood flow decreases oxygen availability in target tissues. Cellular hypoxia leads to mitochondrial dysfunction, decreased energy production, and increased production of reactive oxygen species. To determine the alteration in expression of mitochondrial genes after hypoxia in cardiomyocytes, we developed a rodent mitochondrial gene chip (RoMitoChip). The chip had 1088 probe sets including 46 probe sets representing 37 mouse mitochondrial DNA transcripts and the remaining probe sets representing mouse nuclear genes contributing to the mitochondrial structure and function. Mouse cardiomyocytes isolated from neonatal C57BL/6 mice that were subjected to hypoxia (1% oxygen) for different time intervals demonstrated a dichotomy in the expression profile of tRNA and mRNA transcripts. We report a total of 483 signature genes that were altered by hypoxia in the cardiac myocytes and related to mitochondrial structure and function. This includes 23 transcripts on mitochondrial DNA. Pathway analysis demonstrated predominant changes in the expression of genes involved in oxidative phosphorylation, glucose and fatty acid metabolism, and apoptosis. The most upregulated genes after 24 h of hypoxia included hypoxia-inducible factor 1, alpha subunit, inducible genes Bnip3, Pdk1, and Aldoc. Whereas Bnip3 is important in the cardiomyocyte death pathway, Pdk1 enzyme is critical in conserving mitochondrial function by diverting metabolic intermediates to glycolysis. This study identifies the participation of two important pathways, cell death and glycolytic, and two key proteins, Bnip3 and Pdk1, playing critical roles in these pathways in cardiomyocytes after severe hypoxia.
    Shock (Augusta, Ga.) 02/2010; 34(2):169-75. DOI:10.1097/SHK.0b013e3181cffe7d · 2.73 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Functional expression of KAL1 gene is critical in the migration of GnRH neurons from the olfactory placode to the hypothalamus in embryogenesis. This gene thus far has not been shown to play a functional role in any other physiological or pathological process either in the developed brain or in peripheral tissues. We show here that KAL1 gene expression is decreased in early stage and increased in later stages of cancers. Screening of colon, lung and ovarian cancer cDNA panels indicated significant decrease in KAL1 expression in comparison to corresponding uninvolved tissues. However, KAL1 expression increased with the progression of cancer from early (I and II) stages to later (III and IV) stages of the cancer. There was a direct correlation between the TGFbeta and KAL1 expression in colon cancer cDNA. Using colon cancer cell lines, we showed that TGFbeta induces KAL1 gene expression and secretion of anosmin-1 protein (KAL1 coded protein). We further report that hypoxia induces anosmin-1 expression; anosmin-1 protects cancer cells from apoptosis activated by hypoxia and increases cancer cell mobility. Using siRNA technique we found that KAL1 expression following hypoxia is hypoxia-inducible factor (HIF-1)alpha dependent. Our results suggest that KAL1 gene expression plays an important role in cancer metastasis and protection from apoptosis.
    Cell cycle (Georgetown, Tex.) 11/2009; 8(22):3770-6. DOI:10.4161/cc.8.22.10066 · 5.01 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Reduced immune function is frequently a consequence of serious injury such as trauma-hemorrhage (T-H). Injury may lead to reduced T-cell activation, resulting in decreased engagement of costimulatory molecules after antigen recognition and in subsequent immunological compromise and anergy. We hypothesized that inhibition of CD28 expression is one possible mechanism by which immune functions are suppressed after T-H. Male C3H/HeN mice (with or without ovalbumin immunization) were subjected to sham operation or T-H and sacrificed after 24 hours. Splenic T cells were then stimulated with concanavalin A or ovalbumin in vivo or in vitro, and CD28, cytotoxic T-lymphocyte antigen 4 (CTLA-4), CD69, and phospho-Akt expression was determined. T-cell proliferation/cytokine production was measured in vitro. Stimulation-induced CD69, CD28, and phospho-Akt up-regulation were significantly impaired after T-H compared with sham-operated animals; however, CTLA-4 expression was significantly higher in the T-H group. Over a 3-day span, stimulated T cells from sham-operated animals showed significantly higher proliferation compared with the T-H group. IL-2 and IFN-gamma were elevated in sham-operated animals, whereas IL-4 and IL-5 rose in the T-H group, revealing a shift from T(H)1 to T(H)2 type cytokine production after T-H. Dysregulation of the T-cell costimulatory pathway is therefore likely to be a significant contributor to post-traumatic immune suppression.
    American Journal Of Pathology 10/2009; 175(4):1504-14. DOI:10.2353/ajpath.2009.081174 · 4.60 Impact Factor
  • Raghavan Raju, Christiane S Hampe
    [Show abstract] [Hide abstract]
    ABSTRACT: The two possibilities to explain the pathogenic basis of stiff-person syndrome (SPS) are intrathecal sensitization of GAD65-reactive CD4+T cells and synthesis of GAD65-specific autoantibodies within the CNS [Rakocevic et al., Arch. Neurol. 61: 902-904, 2004]; and peripheral antigen sensitization followed by CNS antigen recognition by autoantibodies that cross the blood-brain barrier. Antigen-specific CD4+ T cells are essential for the generation of high-affinity autoantibodies [Lanzavecchia, Nature 314: 537-539, 1985], but there is no evidence of cellular infiltration in the CNS of SPS patients [Warich-Kirches et al., Clin. Neuropathol. 16: 214-219, 1997; Ishizawa et al., Acta Neuropathol.(Berl) 97: 63-70, 1999]. This review discusses the possible role of autoantibodies and autoreactive T cells specific to neuronal antigens in SPS pathogenesis.
    International Reviews Of Immunology 08/2009; 27(1-2):79-92. DOI:10.1080/08830180701883240 · 5.28 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Sepsis is a systemic inflammatory response caused by infection and is a major cause of mortality after serious injuries and infections. The pathogenesis of sepsis involves several factors such as genetic interaction, pathogen recognition and biological processes that control host responses. Many animal models have been described by various investigators in the study of the pathobiology of sepsis and systemic inflammatory response. In this report we review all the important experimental models that have been used in the study of sepsis, including endotoxin, bacteremia, exogenous peritonitis, and exogenous cecal ligation and perforation models. Notwithstanding the limitations, these models are extensively used by investigators to understand the disease process and to perform pre-clinical studies to test various treatment strategies.
    Sepsis and Non-Infectious Systemic Inflammation: From Biology to Critical Care, 05/2009: pages 373 - 389; , ISBN: 9783527626151
  • [Show abstract] [Hide abstract]
    ABSTRACT: Report a double-blind, placebo-controlled study of rituximab in patients with anti-MAG demyelinating polyneuropathy (A-MAG-DP). Twenty-six patients were randomized to four weekly infusions of 375 mg/m(2) rituximab or placebo. Sample size was calculated to detect changes of > or = 1 Inflammatory Neuropathy Course and Treatment (INCAT) leg disability scores at month 8. IgM levels, anti-MAG titers, B cells, antigen-presenting cells, and immunoregulatory T cells were monitored every 2 months. Thirteen A-MAG-DP patients were randomized to rituximab and 13 to placebo. Randomization was balanced for age, electrophysiology, disease duration, disability scores, and baseline B cells. After 8 months, by intention to treat, 4 of 13 rituximab-treated patients improved by > or = 1 INCAT score compared with 0 of 13 patients taking placebo (p = 0.096). Excluding one rituximab-randomized patient who had normal INCAT score at entry, and thus could not improve, the results were significant (p = 0.036). The time to 10m walk was significantly reduced in the rituximab group (p = 0.042) (intention to treat). Clinically, walking improved in 7 of 13 rituximab-treated patients. At month 8, IgM was reduced by 34% and anti-MAG titers by 50%. CD25+CD4+Foxp3+ regulatory cells significantly increased by month 8. The most improved patients were those with high anti-MAG titers and most severe sensory deficits at baseline. Rituximab is the first drug that improves some patients with A-MAG-DP in a controlled study. The benefit may be exerted by reducing the putative pathogenic antibodies or by inducing immunoregulatory T cells. The results warrant confirmation with a larger trial.
    Annals of Neurology 03/2009; 65(3):286-93. DOI:10.1002/ana.21577 · 11.91 Impact Factor

Publication Stats

608 Citations
163.50 Total Impact Points


  • 2015
    • Georgia Regents University
      • Department of Biochemistry and Molecular Biology
      Augusta, Georgia, United States
  • 2008–2013
    • University of Alabama at Birmingham
      • • Department of Surgery
      • • Department of Microbiology
      Birmingham, Alabama, United States
  • 2010
    • Ludwig Boltzmann Institute for Experimental and Clinical Traumatology
      Wien, Vienna, Austria
  • 2003–2009
    • National Institutes of Health
      Maryland, United States
  • 2006–2008
    • Northern Inyo Hospital
      BIH, California, United States