In this paper we concentrate on the role of infections in IgA nephropathy both from a pathogenetic and clinic point of view. The current hypotheses as regards the role of infections in the pathogenesis of IgA nephropathy are: (a) role of particular pathogens, (b) chronic exposure to mucosal infections, (c) abnormal handling of commensal microbes (gut microbiota). We also focus on particular infections reported in association with classic IgA nephropathy (HIV, malaria, Chlamydia, Lyme disease), as well as on IgA dominant-infection-associated glomerulonephritis. This is a unique form of glomerulonephritis, where IgA deposition is dominant. It is mostly recognized in old, diabetic patients and in association with staphylococcal infection.
Heparanase (HPSE) is part of the biologic network triggered by ischemia/reperfusion (I/R) injury, a complication of renal transplantation and acute kidney injury. During this period, the kidney or graft undergoes a process of macrophages recruitment and activation. HPSE may therefore control these biologic effects. We measured the ability of HPSE and its inhibitor, SST0001, to regulate macrophage polarization and the crosstalk between macrophages and HK-2 renal tubular cells during in vitro hypoxia/reoxygenation (H/R). Furthermore, we evaluated in vivo renal inflammation, macrophage polarization, and histologic changes in mice subjected to monolateral I/R and treated with SST0001 for 2 or 7 d. The in vitro experiments showed that HPSE sustained M1 macrophage polarization and modulated apoptosis, the release of damage associated molecular patterns in post-H/R tubular cells, the synthesis of proinflammatory cytokines, and the up-regulation of TLRs on both epithelial cells and macrophages. HPSE also regulated M1 polarization induced by H/R-injured tubular cells and the partial epithelial-mesenchymal transition of these epithelial cells by M1 macrophages. All these effects were prevented by inhibiting HPSE. Furthermore, the inhibition of HPSE in vivo reduced inflammation and M1 polarization in mice undergoing I/R injury, partially restored renal function and normal histology, and reduced apoptosis. These results show for the first time that HPSE regulates macrophage polarization as well as renal damage and repair after I/R. HPSE inhibitors could therefore provide a new pharmacologic approach to minimize acute kidney injury and to prevent the chronic profibrotic damages induced by I/R.-Masola, V., Zaza, G., Bellin, G., Dall'Olmo, L., Granata, S., Vischini, G., Secchi, M. F., Lupo, A., Gambaro, G., Onisto, M. Heparanase regulates the M1 polarization of renal macrophages and their crosstalk with renal epithelial tubular cells after ischemia/reperfusion injury.
BackgroundIschemia/reperfusion (I/R) is an important cause of acute renal failure and delayed graft function, and it may induce chronic renal damage by activating epithelial to mesenchymal transition (EMT) of renal tubular cells. Heparanase (HPSE), an endoglycosidase that regulates FGF-2 and TGFβ-induced EMT, may have an important role. Therefore, aim of this study was to evaluate its role in the I/R-induced renal pro-fibrotic machinery by employing in vitro and in vivo models.MethodsWild type (WT) and HPSE-silenced renal tubular cells were subjected to hypoxia and reoxygenation in the presence or absence of SST0001, an inhibitor of HPSE. In vivo, I/R injury was induced by bilateral clamping of renal arteries for 30 min in transgenic mice over-expressing HPSE (HPA-tg) and in their WT littermates. Mice were sacrificed 48 and 72 h after I/R. Gene and protein EMT markers (α-SMA, VIM and FN) were evaluated by bio-molecular and histological methodologies.ResultsIn vitro: hypoxia/reoxygenation (H/R) significantly increased the expression of EMT-markers in WT, but not in HPSE-silenced tubular cells. Notably, EMT was prevented in WT cells by SST0001 treatment. In vivo: I/R induced a remarkable up-regulation of EMT markers in HPA-tg mice after 48–72 h. Noteworthy, these effects were absent in WT animals.ConclusionsIn conclusion, our results add new insights towards understanding the renal biological mechanisms activated by I/R and they demonstrate, for the first time, that HPSE is a pivotal factor involved in the onset and development of I/R-induced EMT. It is plausible that in future the inhibition of this endoglycosidase may represent a new therapeutic approach to minimize/prevent fibrosis and slow down chronic renal disease progression in native and transplanted kidneys.
Pain is a prominent feature of multiple myeloma (MM) and may be caused by different underlying causes and mechanisms. Indeed, pain may be due to disease-related complications, iatrogenic causes or may be associated with other unrelated medical conditions. This symptom may be particularly devastating and can negatively affect the quality of life of the afflicted patients and their functional status. For most MM patients suffering from continuous nociceptive pain, the WHO's three-step analgesic ladder can provide adequate relief with oral options, although the high prevalence in MM patients of difficult-to-treat pains, such as pains due to skeletal mechanical instability or sustained by neuropathic mechanisms, makes the treatment approach a challenging concern. The management of pain in this setting requires a multidisciplinary approach integrating analgesics and causal interventions. This review focuses on the most common syndromes afflicting MM patients, attempting to provide an understanding of the underlying pain mechanisms and a discussion of the most commonly used treatment strategies.
Pain in patients with impaired renal function may be a significant problem requiring treatment with opioids. However, pharmacokinetic and metabolic changes associated with an impaired renal function may raise some concerns about side effects and overdosing associated with opioid agents in this patient's population. In order to give recommendations on this issue, we review the available evidences on the pharmacokinetics and side effects of most common opioids used to treat pain. The results of this review show that the half-life of the parent opioid compounds and of their metabolites is increased in the presence of renal dysfunction, for which careful monitoring of the patient, dose reduction and a longer time interval between doses are recommended. Among opioids, morphine and codeine used with very caution and possibly avoided in renal failure/dialysis patients; tramadol, hydromorphone and oxycodone can be used with caution and close patient's monitoring, whereas transdermal buprenorphine, methadone and fentanyl/sufentanil appear to be safe to use in patients with renal failure.
14 days for the household. 1 Dialysis patients can be considered as immunocompromised and display a decreased ability to develop seroconversion to infectious diseases. 2 Therefore, 7 to 14 days may not be an appropriate threshold in a dialysis population. In our center, we provide dialysis in 2 hospital-based and 6 satellite units, for a total of 664 patients (see Supplementary Methods). We isolated our COVID-19-positive dialysis outpatients in a dedicated unit and followed a pathway for de-escalation of stable patients with serial COVID-19 swabs, starting 7 days after confirmed diagnosis (Figure 1, Supplementary Table S1). Thirtyfour COVID-19-positive patients who had at least 3 swabs were included: 20 patients were de-isolated in less than 14 days (59%) with 9% on day 9. By day 12, 35% of patients could be dialyzed in their base unit (which is crucial for capacity). However, by day 15, 14 patients (41%) had not cleared the virus and could not be repatriated: 5 patients cleared the virus later (median of 18 days [range, 16-21]) and 9 patients were still positive or had only one negative swab at the end of follow-up. It is unclear whether detection of viral RNA represents the ability to transmit the virus, 3,4 but until more evidence is available, it would be prudent to isolate patients as discussed to prevent cross-contamination in this high-risk population.
Renal ischemia/reperfusion (I/R) injury occurs in patients undergoing renal transplantation and with acute kidney injury and is responsible for the development of chronic allograft dysfunction as characterized by parenchymal alteration and fibrosis. Heparanase (HPSE), an endoglycosidase that regulates EMT and macrophage polarization, is an active player in the biological response triggered by ischemia/reperfusion (I/R) injury.I/R was induced in vivo by clamping left renal artery for 30 min in wt C57BL/6J mice. Animals were daily treated and untreated with Roneparstat (an inhibitor of HPSE) and sacrificed after 8 weeks. HPSE, fibrosis, EMT-markers, inflammation and oxidative stress were evaluated by biomolecular and histological methodologies together with the evaluation of renal histology and measurement of renal function parameters.8 weeks after I/R HPSE was upregulated both in renal parenchyma and plasma and tissue specimens showed clear evidence of renal injury and fibrosis. The inhibition of HPSE with Roneparstat-restored histology and fibrosis level comparable with that of control. I/R-injured mice showed a significant increase of EMT, inflammation and oxidative stress markers but they were significantly reduced by treatment with Roneparstat. Finally, the inhibition of HPSE in vivo almost restored renal function as measured by BUN, plasma creatinine and albuminuria.The present study points out that HPSE is actively involved in the mechanisms that regulate the development of renal fibrosis arising in the transplanted organ as a consequence of ischemia/reperfusion damage. HPSE inhibition would therefore constitute a new pharmacological strategy to reduce acute kidney injury and to prevent the chronic pro-fibrotic damage induced by I/R.
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