High-content screening assay-based discovery of paullones as novel podocyte-protective agents.

Podocyte dysfunction and loss is an early event and a hallmark of proteinuric kidney diseases. A podocyte's normal function is maintained via its unique cellular architecture that relies on an intracellular network of filaments, including filamentous actin (F-actin) and microtubules, that provides mechanical support. Damage to this filamentous network leads to changes in cellular morphology and results in podocyte injury, dysfunction, and death. Conversely, stabilization of this network protects podocytes and ameliorates proteinuria. This suggests that stabilization of podocyte architecture via its filamentous network could be a key therapeutic strategy for proteinuric kidney diseases. However, development of podocyte-directed therapeutics, especially those that target the cell's filamentous network, is still lacking, partly because of unavailability of appropriate cellular assays for use in a drug discovery environment. Here, we describe a new high-content screening-based methodology and its implementation on podocytes to identify paullone derivatives as a novel group of podocyte-protective compounds. We find that three compounds, i.e., kenpaullone, 1-azakenpaullone, and alsterpaullone, dose dependently protect podocytes from puromycin aminonucleoside (PAN)-mediated injury in vitro by reducing PAN-induced changes in both the filamentous actin and microtubules, with alsterpaullone providing maximal protection. Mechanistic studies further show that alsterpaullone suppressed PAN-induced activation of signaling downstream of GSK3ß and p38 mitogen-activated protein kinase. In vivo it reduced ADR-induced glomerular injury in a zebrafish model. Together, these results identify paullone derivatives as novel podocyte-protective agents for future therapeutic development.

No evidence of uptake or propagation of reindeer CWD prions in environmentally exposed sheep.

BACKGROUND: Chronic wasting disease (CWD) is a prion disease of cervids first reported in North America in the 1960s. In Europe, CWD was first diagnosed in 2016 in a wild reindeer in Norway. Detection of two more cases in the same mountain area led to the complete culling of this partially confined reindeer population of about 2400 animals. A total of 19 CWD positive animals were identified. The affected area is extensively used for the grazing of sheep during summers. There are many mineral licks intended for sheep in the area, but these have also been used by reindeer. This overlap in area use raised concerns for cross-species prion transmission between reindeer and sheep. In this study, we have used global positioning system (GPS) data from sheep and reindeer, including tracking one of the CWD positive reindeer, to investigate spatial and time-relevant overlaps between these two species. Since prions can accumulate in lymphoid follicles following oral uptake, samples of gut-associated lymphoid tissue (GALT) from 425 lambs and 78 adult sheep, which had grazed in the region during the relevant timeframe, were analyzed for the presence of prions. The recto-anal mucosa associated lymphoid tissue (RAMALT) from all the animals were examined by histology, immunohistochemistry (IHC) and enzyme-linked immunosorbent assay (ELISA), and the ileal Peyer's patch (IPP) from a subsample of 37 lambs were examined by histology and IHC, for the detection of prions. RESULTS: GPS data showed an overlap in area use between the infected reindeer herd and the sheep. In addition, the GPS positions of an infected reindeer and some of the sampled sheep showed temporospatial overlap. No prions were detected in the GALT of the investigated sheep even though the mean lymphoid follicle number in RAMALT and IPP samples were high. CONCLUSION: The absence of prions in the GALT of sheep that have shared pasture with CWD-infected reindeer, may suggest that transmission of this novel CWD strain to sheep does not easily occur under the conditions found in these mountains. We document that the lymphoid follicle rich RAMALT could be a useful tool to screen for prions in sheep.

Streptococcus intermedius Pleuropulmonary Disease: A Not So Commonly Seen Radiological Picture.

A Streptococcus (S.) intermedius-associated pleuropulmonary infection (PPI) is a rare presentation. Cases have been reported in the last decade in which S. intermedius was identified in pleural fluid cultures and lung biopsies in patients presenting with complicated pleural effusions and empyema. However, there are data lacking on predisposing factors, mode of dissemination, and treatment strategies for these patients. Moreover, these patients can present with a spectrum of radiographic findings, which can help with prompt diagnosis and effective patient management. However, the radiological findings in this patient and the rapidly worsening clinical symptoms make the diagnosis difficult.

An Unfortunate Case of Reactivation of Tuberculosis in a Postpartum Female.

Tuberculosis (TB) is a widely prevalent disease, especially in resource-limited settings. It poses a big burden to the community and is a significant cause of morbidity and mortality in pregnant females due to their immunosuppressed state. During pregnancy, the immune system is suppressed to prevent fetal rejection, and it gets reconstituted postpartum. During this reconstitution phase, reactivation of TB may occur, making it quintessential to test peripartum females for latent TB, especially those belonging to endemic regions. We describe an unfortunate case of reactivation of TB in a postpartum female from Central America.

The MMP9 rs17576 A>G polymorphism is associated with increased lumbopelvic pain-intensity in pregnant women.

BACKGROUND AND AIMS: Matrix metalloproteinase 9 (MMP9) is an enzyme that may affect degradation of several extracellular matrix (ECM) components in the pelvic ligaments during pregnancy. Previous studies indicate that genetic variations in the gene encoding MMP9 may affect the enzymatic activity. One such genetic variant is a single nucleotide polymorphism (SNP), rs17576 A>G. In this study we investigated whether the MMP9 SNP rs17576 A>G may be associated with increased lumbopelvic pain in 838 pregnant woman. The study was registered with ClinicalTrials.gov (NCT 00476567) on May 21, 2007. METHODS: Lumbopelvic pain-intensity was measured by visual analog scale (VAS) at two time points during pregnancy, T1 (18-22 weeks), T2 (32-36 weeks) and 3 months after delivery. Blood samples were collected at each point and SNP genotyping was carried out using predesigned TaqMan SNP genotyping assays. RESULTS: The results showed a significant association between the number of G alleles and pain-intensity in the evening at T2. The pain among G/G carriers was higher than among A/G carriers, which in turn was higher than among the A/A carriers. The most pronounced association between the G allele and pain-intensity was observed in primiparae. CONCLUSIONS: We conclude that the MMP9 rs17576 A>G polymorphism is associated with increased lumbopelvic pain-intensity during pregnancy. The present data support the hypothesis that lumbopelvic pain during pregnancy may be related to a relaxin - MMP9 - tissue remodeling mechanism. IMPLICATIONS: The present findings may be important for future mechanistic studies on how MMP9 rs17576 A>G may affect changes in the ECM components in pelvic ligaments and lumbopelvic pain-intensity during pregnancy.

Genetic predictors of recovery in low back and lumbar radicular pain.

Previous data suggest that persistent back pain may be associated with genetic variability. In this study, we assessed the correlation between 8 genetic polymorphisms (VDR, COL11, MMP1, MMP9, IL-1α, IL-1RN, OPRM1, COMT) and pain recovery in patients with low back pain (LBP) and lumbar radicular pain (LRP). In total, 296 patients with LBP or LRP were followed for 5 years. The patients underwent standardized clinical examination and completed pain and function questionnaires. Univariate linear regression associations with P values <0.1 were included in the multivariable analysis, adjusting for pain intensity at baseline, age, sex, smoking, body mass index, and LBP or LRP. Pain intensity at 5-year follow-up was associated with VDR rs731236 (B = -0.5, 95% confidence interval [CI] -0.9 to -0.1, P = 0.017), MMP9 rs17576 (B = 0.5, 95% CI 0.1-0.9, P = 0.022), and OPRM1 rs1799971 (B = -0.8, 95% CI -1.4 to -0.2, P = 0.006) in the univariate analyses. MMP9 rs17576 and OPRM1 rs1799971 remained significant (B = 0.4, 95% CI 0.05-0.8, P = 0.026 and B = -0.8, 95% CI -1.3 to -0.2, P = 0.007) in the multivariable model. Thus, the data demonstrated that the rare allele of MMP9 rs17576 was associated with poor pain recovery, whereas the rare allele of OPRM1 rs1799971 was associated with better pain recovery at 5-year follow-up in the LBP and LRP patients. In particular, the present study suggested that the OPRM1 rs179971 A>G in men was associated with better long-term pain recovery. In men, the OPRM1 rs1799971 explained 4.7% of the variance of pain intensity. We conclude that the MMP9 rs17576 and OPRM1 rs1799971 genotypes may affect 5-year recovery in patients with LBP and LRP.

Inhibition of fatty acid amide hydrolase (FAAH) reduces spinal nociceptive responses and expression of spinal long-term potentiation (LTP).

Fatty acid amide hydrolase (FAAH) is an enzyme that metabolizes endocannabinoids and fatty acid amides possibly linked to activation of the opioid system. To examine how this enzyme affects spinal signalling, electrophysiological recordings in the dorsal horn and qPCR on dorsal horn tissue following systemic administration of the FAAH inhibitor URB597 (0.3 and 1.0mg/kg i.v.) and spinal administration of the opioid receptor antagonist naloxone (0.1 µg/µl i.th.), were performed. The present data showed that the suppressive effect of the FAAH inhibitor URB597 (1.0mg/kg i.v.) on the spinal nociceptive responses was prevented by spinal administration of the opioid receptor antagonist naloxone (0.1 µg/µl i.th.). Moreover, the present findings demonstrated that the FAAH inhibitor URB597 (1.0mg/kg i.v.) partly reversed expression of spinal long-term potentiation (LTP) and also attenuated the LTP-associated increased Zif expression. We conclude that pharmacological inactivation of FAAH may be a promising strategy to inhibit the development of central hyperalgesia; thereby reinforcing the role of FAAH as a potential therapeutic target.