Physiological properties of astroglial cell lines derived from mice with high (SAMP8) and low (SAMR1, ICR) levels of endogenous retrovirus

Previous studies have reported that various inbred SAM mouse strains differ markedly with regard to a variety of parameters, such as capacity for learning and memory, life spans and brain histopathology. A potential cause of differences seen in these strains may be based on the fact that some strains have a high concentration of infectious murine leukemia virus (MuLV) in the brain, whereas other strains have little or no virus. To elucidate the effect of a higher titer of endogenous retrovirus in astroglial cells of the brain, we established astroglial cell lines from SAMR1 and SAMP8 mice, which are, respectively, resistant and prone to deficit in learning and memory and shortened life span. MuLV-negative astroglial cell lines established from ICR mice served as controls. Comparison of these cell lines showed differences in: 1) levels of the capsid antigen CAgag in both cell lysates and culture media, 2) expression of genomic retroelements, 3) the number of virus particles, 4) titer of infectious virus, 5) morphology, 6) replication rate of cells in culture and final cell concentrations, 7) expression pattern of proinflammatory cytokine genes. The results show that the expression of MuLV is much higher in SAMP8 than SAMR1 astrocyte cultures and that there are physiological differences in astroglia from the 2 strains. These results raise the possibility that the distinct physiological differences between SAMP8 and SAMR1 are a function of activation of endogenous retrovirus

EcoHIV infection of mice establishes latent viral reservoirs in T cells and active viral reservoirs in macrophages that are sufficient for induction of neurocognitive impairment

Suppression of HIV replication by antiretroviral therapy (ART) or host immunity can prevent AIDS but not other HIV-associated conditions including neurocognitive impairment (HIV-NCI). Pathogenesis in HIV-suppressed individuals has been attributed to reservoirs of latent-inducible virus in resting CD4+ T cells. Macrophages are persistently infected with HIV but their role as HIV reservoirs in vivo has not been fully explored. Here we show that infection of conventional mice with chimeric HIV, EcoHIV, reproduces physiological conditions for development of disease in people on ART including immunocompetence, stable suppression of HIV replication, persistence of integrated, replication-competent HIV in T cells and macrophages, and manifestation of learning and memory deficits in behavioral tests, termed here murine HIV-NCI. EcoHIV established latent reservoirs in CD4+ T lymphocytes in chronically-infected mice but could be induced by epigenetic modulators ex vivo and in mice. In contrast, macrophages expressed EcoHIV constitutively in mice for up to 16 months; murine leukemia virus (MLV), the donor of gp80 envelope in EcoHIV, did not infect macrophages. Both EcoHIV and MLV were found in brain tissue of infected mice but only EcoHIV induced NCI. Murine HIV-NCI was prevented by antiretroviral prophylaxis but once established neither persistent EcoHIV infection in mice nor NCI could be reversed by long-acting antiretroviral therapy. EcoHIV-infected, athymic mice were more permissive to virus replication in macrophages than were wild-type mice, suffered cognitive dysfunction, as well as increased numbers of monocytes and macrophages infiltrating the brain. Our results suggest an important role of HIV expressing macrophages in HIV neuropathogenesis in hosts with suppressed HIV replication

Motor Unit Number Estimation in Evaluating Disease Progression in Patients with Amyotrophic Lateral Sclerosis

We investigated the availability of motor unit number estimation (MUNE) as a quantitative method to assess the severity and clinical progression of amyotrophic lateral sclerosis (ALS). The 143 ALS patients were evaluated by statistical MUNE and the revised amyotrophic lateral sclerosis functional rating scale (ALSFRS-R). By using mean values of MUNE according to disease duration, regression equation between mean MUNE and disease duration was presented as a formula. The individual MUNE ratio was calculated by dividing individual MUNE value by mean MUNE value. All patients were classified into 2 groups (MUNE ratio <1 vs. MUNE ratio ≥1) according to the MUNE ratio. Comparison between the 2 groups revealed that the patients in MUNE ratio <1 group or MUNE ratio ≥1 group were respectively assigned to rapid progression or slow progression. We recommended informative mean values of MUNE and best regression equation in ALS patients according to disease duration. These values allow us to evaluate the severity and rapidity of progression in ALS

Cellular Prion Protein Combined with Galectin-3 and -6 Affects the Infectivity Titer of an Endogenous Retrovirus Assayed in Hippocampal Neuronal Cells.

Prion diseases are infectious and fatal neurodegenerative diseases which require the cellular prion protein, PrPC, for development of diseases. The current study shows that the PrPC augments infectivity and plaque formation of a mouse endogenous retrovirus, MuLV. We have established four neuronal cell lines expressing mouse PrPC, PrP+/+; two express wild type PrPC (MoPrPwild) and the other two express mutant PrPC (MoPrPmut). Infection of neuronal cells from various PrP+/+ and PrP-/- (MoPrPKO) lines with MuLV yielded at least three times as many plaques in PrP+/+ than in PrP-/-. Furthermore, among the four PrP+/+ lines, one mutant line, P101L, had at least 2.5 times as many plaques as the other three PrP+/+ lines. Plaques in P101L were four times larger than those in other PrP+/+ lines. Colocalization of PrP and CAgag was seen in MuLV-infected PrP+/+ cells. In the PrP-MuLV interaction, the involvement of galectin-3 and -6 was observed by immunoprecipitation with antibody to PrPC. These results suggest that PrPC combined with galectin-3 and -6 can act as a receptor for MuLV. P101L, the disease form of mutant PrPC results suggest the genetic mutant form of PrPC may be more susceptible to viral infection

The effect of Korean Red Ginseng extract on rosiglitazone-induced improvement of glucose regulation in diet-induced obese mice

AbstractBackgroundKorean Red Ginseng extract (KRG, Panax ginseng Meyer) and its constituents have been used for treating diabetes. However, in diet-induced obese mice, it is unclear whether KRG can enhance the glucose-lowering action of rosiglitazone (ROSI), a peroxisome proliferator-activated receptor gamma synthetic activator.MethodsOral glucose tolerance tests (oGTTs) were performed after 4 days of treatment with a vehicle (CON), KRG [500 mg/kg body weight (b.w.)], ROSI (3.75 mg/kg b.w, 7.5 mg/kg b.w, and 15 mg/kg b.w.), or ROSI and KRG (RK) in obese mice on a high-fat diet. Adipose tissue morphology, crown-like structures (CLSs), and inflammation were compared by hematoxylin-eosin staining or quantitative reverse transcription polymerase chain reaction.ResultsThe area under the glucose curve (AUC) was significantly lower in the RK group (15 mg/kg b.w. and 500 mg/kg b.w. for ROSI and KRG, respectively) than in the CON group. There was no significant difference in the AUC between the CON and the other groups. Furthermore, the AUC was significantly lower in the RK group than in the ROSI group. The expression of the Ccl2 gene and the number of CLSs were significantly reduced in the RK group than in the CON group.ConclusionOur results show a potential enhancement of ROSI-induced improvement of glucose regulation by the combined treatment with KRG

The cell-cell adhesion mechanisms to form plaques.

<p>(A) Scheme of PrP-MuLV-Gal interaction in cell membrane. (B) Based on our data between the cells PrP-Gal3 has binding activity and Gal3-CAgag-Gal6 shows binding activity. To produce the plaques, Gal3 is suggested to combine between PrP and MuLV. Gal6 is suggested to combine two different viruses to form plaques.</p

Expression levels of the PrP^C genes and proteins in neuronal and astroglial cell lines.

<p>(A) Analysis of expression levels of <i>Prnp</i> in <i>Prnp</i>^-/-, Zpl, Vec, and Za, and <i>Prnp</i>^+/+, ZW, 3F4, PrPΔ, P101L, and ICR cell lines. ZW, 3F4, P101L, and ICR-A cell lines contained full-length of <i>Prnp</i> (789 bp). Cell lines expressing wild-type PrP^C are called the ZW cell line (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167293#pone.0167293.t001" target="_blank">Table 1</a>). PrPΔ cell line contained shorter length <i>Prnp</i> (663 bp). Zpl, Vec, and Za cell lines were negative for <i>Prnp</i> detection. (B) Protein levels of PrP in cell lines were consistent with the results of RT-PCR analysis. PrPΔ cell line showed shorter length PrP. (C) Densitometry analysis of PrP protein expression showed no significant difference between wild-type cells and PrP-transfected cells. Relative values are represented as the mean±SEM. Cell lines were assessed by three separate experiments. ZW 13–2, 100±7.82; 3F4-A3, 87.8±9.53; PrPΔP1-3, 93.8±9.11; P101L-C4, 83.94±9.41; ICR-A3, 88.75±10.23.</p

Primer sequences and conditions for RT-PCR.

<p>Primer sequences and conditions for RT-PCR.</p