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Neurolathyrism is a neurodegenerative disorder characterized by spastic paraplegia resulting from the excessive consumption of Lathyrus sativus (Grass pea). ß-N-Oxalyl-L-α,ß-diaminopropionic acid (L-ODAP) is the primary neurotoxic component in this pea. The present study attempted to evaluate the proteome-wide alterations in chick brain 2 hr and 4 hr post L-ODAP treatment. Proteomic analysis of chick brain homogenates revealed several proteins involved in cytoskeletal structure, signaling, cellular metabolism, free radical scavenging, oxidative stress and neurodegenerative disorders were initially up-regulated at 2 hr and later recovered to normal levels by 4 hr. Since L-ODAP mediated neurotoxicity is mainly by excitotoxicity and oxidative stress related dysfunctions, this study further evaluated the role of L-ODAP in apoptosis in vitro using human neuroblastoma cell line, IMR-32. The in vitro studies carried out at 200 µM L-ODAP for 4 hr indicate minimal intracellular ROS generation and alteration of mitochondrial membrane potential though not leading to apoptotic cell death. L-ODAP at low concentrations can be explored as a stimulator of various reactive oxygen species (ROS) mediated cell signaling pathways not detrimental to cells. Insights from our study may provide a platform to explore the beneficial side of L-ODAP at lower concentrations. This study is of significance especially in view of the Government of India lifting the ban on cultivation of low toxin Lathyrus varieties and consumption of this lentil.

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Hypoxia inducible factor (HIF)-1α, a subunit of HIF transcription factor, regulates cellular response to hypoxia. In normoxic conditions, it is hydroxylated by prolyl hydroxylase (PHD)-2 and targeted for proteosomal degradation. Drugs which inhibit PHD-2 have implications in conditions arising from insufficient blood supply. ß-ODAP (ß-N- oxalyl-L-α, ß- diaminopropionic acid), a non-protein excitatory amino acid present in Lathyrus sativus, is an α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor agonist known to activate conventional protein kinase C and stabilize HIF-1α under normoxic conditions. However, the mechanism of HIF-1α stabilization by this compound is unknown. In silico approach was used to understand the mechanism of stabilization of HIF-1α which revealed ß-ODAP interacts with key amino acid residues and Fe2+ at the catalytic site of PHD-2. These results were further corroborated with luciferase HRE (hypoxia response element) reporter system in HeLa cells. Different chemical modulators of PHD-2 activity and HIF-1α levels were included in the study for comparison. Results obtained indicate that ß-ODAP inhibits PHD-2 and facilitates HIF dependent HRE expression and hence, might be helpful in conditions arising from hypoxia.

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BACKGROUND: Profilins are actin-modulating proteins regulating many intracellular functions based on their multiple and diverse ligand interactions. They have been implicated to play a role in many pathological conditions such as allergies, cardiovascular diseases, muscular atrophy, diabetes, dementia and cancer. Post-translational modifications of profilin 1 can alter its properties and subsequently its function in a cell. In the present study, we identify the importance of phosphorylation of profilin 1 at serine 137 (S137) residue in breast cancer progression. METHODS/PRINCIPAL FINDINGS: We found elevated profilin 1 (PFN) in human breast cancer tissues when compared to adjacent normal tissues. Overexpression of wild-type profilin 1 (PFN-WT) in breast cancer MCF7 cells made them more migratory, invasive and adherent independent in comparison to empty vector transfected cells. Mutation in serine phosphorylation site (S137) of profilin 1 (PFN-S137A) significantly abrogated these properties. Mutation affecting actin-binding ability (PFN-R74E) of profilin 1 enhanced its tumorigenic function whereas mutation affecting its poly-L-proline binding function (PFN-H133S) alleviated these mechanisms in breast cancer cells. PFN-WT was found to activate matrix metalloproteinases by zymography, MMP2 and MMP9 in presence of PDBu (phorbol 12, 13 dibutyrate, PI3K agonist) to enhance migration and invasion in MCF7 cells while PFN-S137A did not. Phosphorylation increased migration and invasion in other mutants of profilin 1. Nuclear profilin levels also increased in the presence of PDBu. CONCLUSIONS: Previous studies show that profilin could be executing a dual role in cancer by either suppressing or promoting tumorigenesis in a context dependent manner. In this study we demonstrate for the first time that phosphorylation of profilin 1 at serine 137 enhances oncogenic properties in breast cancer cells. Inhibitors targeting profilin 1 phosphorylation directly or indirectly through inhibition of kinases that phosphorylate profilin could be valuable therapeutic agents that can alter its activity and thereby control the progression of cancer.

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BACKGROUND/AIM: Interleukin (IL-10) plays a major role in chronic hepatitis C virus (HCV) disease pathogenesis, in particular in Schistosoma mansoni (S. mansoni) co-infected patients. Given that interindividual variations in IL-10 production are influenced by functional polymorphisms in the IL-10 gene promoter, we determined the frequencies of common (-1082, -819 and -592) IL-10 promoter polymorphisms in chronic HCV patients with and without S. mansoni co-infection and healthy controls, and investigated their association with the degree of histological activity index (HAI) and response to interferon-ribavirin therapy. METHODS: Genomic DNA from 99 patients and 62 healthy controls, born in the same geographical hyperendemic area, was studied by the polymerase chain reaction, followed by restriction enzyme digestion. Sera were assessed for S. mansoni antibodies. RESULTS: The frequencies of IL-10 polymorphisms at positions -1082, -819 and -592 from the transcription start site were comparable between HCV patients and controls, as well as between HCV mono-infected and either S. mansoni co-infected patients or controls. The grade of inflammation and the stage of fibrosis showed no association with IL-10 polymorphisms. The frequencies of S. mansoni co-infection and IL-10 genotypes/haplotypes were insignificantly different between non-responders and responders to combination therapy. No effect of other factors like age, gender, HAI group scores and serum alanine aminotransferase and aspartate aminotransferase levels was observed on response to therapy in our patients. CONCLUSION: Our findings suggest that common IL-10 (-1082, -819 and -592) genotypes/haplotypes do not influence the degree of HAI and response to combination therapy or susceptibility to HCV infection with and without S. mansoni co-infection.

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BACKGROUND/AIM: The association between mixed cryogloblinaemia and chronic hepatitis C virus (HCV) infection has been established. However, the factors underlying its great geographical heterogeneity of prevalence have not yet been identified. Concomitant HCV and Schistosoma mansoni infections are common in Egypt. Chronic helminthic infections have been found to decrease the incidence and manifestations of immune-related diseases. To date, no study has focused on the influence of S. mansoni coinfection on the risk of cryoglobulinaemia in hepatitis C patients. METHODS: A cohort of 119 consecutively recruited chronic hepatitis C-infected patients was studied. Patients' sera were assessed for S. mansoni antibodies and cryoglobulins (CGs) were determined and characterized. RESULTS: Cryoglobulins were detected in 18 of 119 patients (15.1%) included in this study. They were detected in 12 of 45 hepatitis C (26.7%) and six of 74 coinfected patients (8.1%), which was statistically significant, P=0.01. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were also found to be significantly lower in the CG-positive group compared with the CG-negative group, P=<0.01. CGs were detected in seven of 21 (33.3%) and in 11 of 98 (11.2%) hepatitis C female and male patients, respectively, indicating a significantly positive association with the female gender, P=0.02. A logistic regression adjusted for gender, AST and ALT showed that hepatitis C patients without schistosomal coinfection are more likely to have cryoglobulinaemia, odds ratio=4.12, 95% confidence interval=1.42-11.95. CONCLUSION: There is an apparent protective effect of S. mansoni coinfection against mixed cryoglobulinaemia in chronic hepatitis C patients.

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BACKGROUND/AIM: The mechanisms of B-cell lymphoproliferative disorders in chronic hepatitis C virus (HCV) infection are unclear. An increased prevalence of circulating monoclonal B-cells and t(14;18) has been reported. Geographic heterogeneity of prevalence of t(14;18) has been shown to exist. We investigated the prevalence of t(14;18) and B-cell clonality as possible mechanisms of lymphomagenesis in chronic HCV patients, in whom cryoglobulinemia status was previously detected. METHODS: A cohort of 111 patients was studied, including 87 patients with chronic HCV disease (18 cryoglobulinemic and 69 non- cryoglobulinemic); 24 HCV-negative, cryoglobulin negative patients with other nonimmune chronic liver diseases were enrolled as controls. The t(14;18) and IgH rearrangement (as a marker of B-cell clonality) were detected by the polymerase chain reaction. RESULTS: t(14;18) was detected in 27.6% of HCV patients and in none of the controls. Detection rates were comparable in both cryoglobulin-positive and negative groups (22.2% and 29% , respectively), p=0.769. IgH rearrangement was detected in 39.1% of HCV patients and in none of the controls. The cryoglobulin-positive group showed significantly higher prevalence of IgH rearrangement compared to the cryoglobulin-negative group (61.1% and 33.3% , respectively), p=0.03, OR=3.13 and 95% CI=1.07-9.17. t(14;18) and monoclonal IgH rearrangement detection rates were not associated with each other, p=0.467. CONCLUSIONS: t(14;18) is uncommon in HCV-mixed cryogoblulinemia Egyptian patients; it does not seem to play a role in HCV-associated MC and lymphomagenesis in our geographical area. HCV may play a role in mixed cryogoblulinemia and lymphomagenesis, probably by inducing clonal B-cell expansions.

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