Epithelial cells exfoliated in human urine can include cells anywhere from the urinary tract and kidneys; however, podocytes and proximal tubular epithelial cells (PTECs) are by far the most relevant cell types for the study of genetic kidney diseases. When maintained in vitro, they have been proven extremely valuable for discovering disease mechanisms and for the development of new therapies. Furthermore, cultured patient cells can individually represent their human sources and their specific variants for personalized medicine studies, which are recently gaining much interest. In this review, we summarize the methodology for establishing human podocyte and PTEC cell lines from urine and highlight their importance as kidney disease cell models. We explore the well-established and recent techniques of cell isolation, quantification, immortalization and characterization, and we describe their current and future applications.

Background: The campaign against epilepsy is hampered by the difference between those with the active disorder and the number of them receiving appropriate treatment (treatment gap) in sub-Saharan Africa. Identifying the determinants of this gap is crucial to providing and achieving optimal care. Objective: To identify the determinants of epilepsy treatment gap (ETG) in children and adolescents (Subjects) with epilepsy in a rural community. Methods: Subjects were identified through a community house to house survey. Information obtained from Subjects and their care givers included: sociodemographic characteristics, type and frequency of epileptic seizures, current and past treatment options utilized, reasons for treatment options used, and treatment options utilized for other health complaints. Results: Twenty three Subjects (6.4/1000 of the child and adolescent population) were identified as having epilepsy. Their age range was 4-19 years (mean 14.3±4.7 years). Most were males (82.6%) and adolescents (78.3%). Seizures were mostly generalized (95.7%) and occurred most frequently daily. Current treatment modalities were use of traditional medication (100%) and prayers (34.8%).None was currently on orthodox medical therapy (ETG, 100%) but 5(21.7%) had utilized orthodox medical therapy in the past. The main determinants of the ETG were strong cultural belief, weakness in the health system to epilepsy treatment and low socioeconomic status. Fever was the commonest other health complaint and use of orthodox medical therapy was significantly (p˂ 0.05) the main (16, 69.6%) treatment option utilized. Conclusion: Cultural belief, weak health system and low socioeconomic status were determinants of an absolute ETG. It highlights the need to strengthen initiatives that enhance accessibility to standard epilepsy treatment.

Apolipoprotein L1 (APOL1) high-risk genotypes (HRG), G1 and G2, increase the risk of various non-diabetic kidney diseases in the African population. To date, the precise mechanisms by which APOL1 risk variants induce injury on podocytes and other kidney cells remain unclear. Trying to unravel these mechanisms, most studies have used animal or cell models created by gene editing. We developed and characterised conditionally immortalised human podocyte cell lines derived from urine of a donor carrying APOL1 HRG G2/G2. Following induction of APOL1 expression by polyinosinic-polycytidylic acid (poly(I:C)), we assessed functional features of APOL1-induced podocyte dysfunction. As control, APOL1 wild type (G0/G0) podocyte cell line previously generated from a Caucasian donor was used. Upon exposure to poly(I:C), G2/G2 and G0/G0 podocytes upregulated APOL1 expression resulting in podocytes detachment, decreased cells viability and increased apoptosis rate in a genotype-independent manner. Nevertheless, G2/G2 podocyte cell lines exhibited altered features, including upregulation of CD2AP, alteration of cytoskeleton, reduction of autophagic flux and increased permeability in an in vitro model under continuous perfusion. The human APOL1 G2/G2 podocyte cell model is a useful tool for unravelling the mechanisms of APOL1-induced podocyte injury and the cellular functions of APOL1.

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Kidney damage has been associated with administration diclofenac, a phenylacetic acid derivative belonging to the nonsteroidal anti-inflammatory drugs (NSAIDs), which is commonly used for the treatment of various diseases such as rheumatoid arthritis, ankylosing spondylitis, acute muscle pain conditions and osteoarthritis. This study investigated the exact mechanism of diclofenac in renal toxicity by determining the involvement of oxidative stress in rats. Adult male Wistar rats were divided into two groups of eight rats in each group and orogastrically treated for three days. Group 1 served as the normal control and received normal saline (0.9% w/v) and group 2 received 40 mg/kg body weight of diclofenac for three days. Administration of diclofenac caused degeneration of the kidney of rats as evidenced by significant elevation in the serum levels of creatinine, urea, albumin, uric acid, protein and electrolytes and the activities of renal-5'-nucleotidase and glucose-6-phosphate-dehydrogenase (G6PDH) compared with control. Furthermore, administration of diclofenac decreased the activities of superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), and glutathione-S-transferase (GST) and the level of glutathione with concomitant increase in hydrogen peroxide (H 2 O 2) and malondialdehyde (MDA) levels in the kidney of the diclofenac treated groups compared with control. These findings reveal that administration of diclofenac may impair kidney functions through induction of oxidative stress.

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The calcineurin inhibitors (CNI) cyclosporine A and tacrolimus comprise the basis of immunosuppressive regimes in all solid organ transplantation. However, long-term or high exposure to CNI leads to histological and functional renal damage (CNI-associated nephrotoxicity). In the kidney, proximal tubule cells are the only cells that metabolize CNI and these cells are believed to play a central role in the origin of the toxicity for this class of drugs, although the underlying mechanisms are not clear. Several studies have reported oxidative stress as an important mediator of CNI-associated nephrotoxicity in response to CNI exposure in different available proximal tubule cell models. However, former models often made use of supra-therapeutic levels of tissue drug exposure. In addition, they were not shown to express the relevant enzymes (e.g., CYP3A5) and transporters (e.g., P-glycoprotein) for the metabolism of CNI in human proximal tubule cells. Moreover, the used methods for detecting ROS were potentially prone to false positive results. In this study, we used a novel proximal tubule cell model established from human allograft biopsies that demonstrated functional expression of relevant enzymes and transporters for the disposition of CNI. We exposed these cells to CNI concentrations as found in tissue of stable solid organ transplant recipients with therapeutic blood concentrations. We measured the glutathione redox balance in this cell model by using organelle-targeted variants of roGFP2, a highly sensitive green fluorescent reporter protein that dynamically equilibrates with the glutathione redox couple through the action of endogenous glutaredoxins. Our findings provide evidence that CNI, at concentrations commonly found in allograft biopsies, do not alter the glutathione redox balance in mitochondria, peroxisomes, and the cytosol. However, at supra-therapeutic concentrations, cyclosporine A but not tacrolimus increases the ratio of oxidized/reduced glutathione in the mitochondria, suggestive of imbalances in the redox environment.

Clinical and genetic factors have been reported as influencing the development of sickle cell nephropathy (SCN). However, such data remain limited in the paediatric population. In this cross-sectional study, we enrolled 361 sickle cell disease children from the Democratic Republic of Congo. Participants were genotyped for the beta (b)-globin gene, apolipoprotein L1 (APOL1) risk variants, and haem oxygenase-1 (HMOX1) GT-dinucleotide repeats. As markers of kidney damage, albuminuria, hyperfiltration and decreased estimated glomerular filtration with creatinine (eGFRcr) were measured. An association of independent clinical and genetic factors with these markers of kidney damage were assessed via regression analysis. Genetic sequencing confirmed sickle cell anaemia in 326 participants. Albuminuria, hyperfiltration and decreased eGFRcr were present in 65 (20%), 52 (16%) and 18 (5Á5%) patients, respectively. Regression analysis revealed frequent blood transfusions, indirect bilirubin and male gender as clinical predictors of SCN. APOL1 high-risk genotype (G1/G1, G2/G2 and G1/G2) was significantly associated with albuminuria (P = 0Á04) and hyperfiltration (P = 0Á001). HMOX1 GT-dinucleotide long repeats were significantly associated with lower eGFRcr. The study revealed a high burden of kidney damage among Congolese children and provided evidence of the possible role of APOL1 and HMOX1 in making children more susceptible to kidney complications.