bims-bicyki Biomed News
on Bicaudal-C1 and interactors in cystic kidney disease
Issue of 2021‒07‒18
twenty-five papers selected by
Céline Gagnieux
École Polytechnique Fédérale de Lausanne (EPFL)

  1. Clin Exp Nephrol. 2021 Jul 12.
      BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is a monogenic kidney disorder that impairs renal functions progressively leading to kidney failure. The disease affects between 1:400 and 1:1000 ratio of the people worldwide. It is caused by the mutated PKD1 and PKD2 genes which encode for the defective polycystins. Polycystins mimic the receptor protein or protein channel and mediate aberrant cell signaling that causes cystic development in the renal parenchyma. The cystic development is driven by the increased cyclic AMP stimulating fluid secretion and infinite cell growth. In recent years, natural product-derived small molecules or drugs targeting specific signaling pathways have caught attention in the drug discovery discipline. The advantages of natural products over synthetic drugs enthusiast researchers to utilize the medicinal benefits in various diseases including ADPKD.CONCLUSION: Overall, this review discusses some of the previously studied and reported natural products and their mechanisms of action which may potentially be redirected into ADPKD.
    Keywords:  ADPKD; Cell proliferation; Fluid secretion; cAMP
  2. Ren Fail. 2021 Dec;43(1): 1124-1129
      BACKGROUND: In autosomal dominant polycystic kidney disease (ADPKD), endothelial dysfunction (ED) is common and occurs much earlier than kidney function impairment. The impact of smoking on ED in ADPKD patients has not been previously studied. The aim of this study was to investigate the potential contribution of smoking habits to ED and subclinical atherosclerosis in these patients.METHODS: This case-control study included 54 ADPKD patients with preserved renal function and 45 healthy control subjects. ED was assessed using ischemia-induced forearm flow-mediated dilatation (FMD). Carotid intima-media thickness (CIMT) was measured from 10 mm proximal to the right common carotid artery. Clinical demographic characteristics and laboratory data were recorded for the patients and control group. Regression analysis was used to determine independent associations of ED and CIMT.
    RESULTS: FMD was significantly lower in the ADPKD patients (19.5 ± 5.63 vs. 16.56 ± 6.41, p = .018). Compared with nonsmoker ADPKD patients, smoker patients had significantly lower FMD values (18.19 ± 6.52 vs. 13.79 ± 5.27, p = .013). In multiple regression analysis, age (β = -0.294, 95% CI: -0.392: -1.96, p = .001) for FMD and smoking (β  =  1.328, 95% CI: 0.251, 2.404, p = .017) for CIMT were independent predictors.
    CONCLUSIONS: Patients with ADPKD had more impaired endothelial function and subclinical atherosclerosis compared with control subjects. Smoking may increase the risk of subclinical atherosclerosis in ADPKD patients.
    Keywords:  Autosomal dominant polycystic kidney disease (ADPKD); endothelial dysfunction; normal kidney function; smoking
  3. Curr Opin Nephrol Hypertens. 2021 Jul 12.
      PURPOSE OF REVIEW: Patients with Autosomal Dominant Polycystic Kidney Disease (ADPKD) reach kidney failure at a median age of 58 years. There has been a strong interest in medical interventions to improve prognosis. With increasing understanding of the underlying pathophysiology, there is also a rationale for non-pharmaceutical interventions. However, these have received little attention. This review, therefore, focuses on dietary interventions in ADPKD.RECENT FINDINGS: Recent studies regarding salt, protein and water intake, caloric restriction, BMI, caffeine and alcohol are discussed in this review. In general, these studies suggest that advices do not need to be different from those in chronic kidney disease (CKD). On the basis of research in the general population and CKD, these advices will likely decrease cardiovascular morbidity and mortality. With respect to delaying ADPKD progression, evidence for salt restriction is growing. For increasing water intake and targeting glucose metabolism by intermittent fasting, preclinical studies are promising. Long-term randomized human intervention studies are, however, lacking.
    SUMMARY: In ADPKD, advices regarding dietary interventions can, in general, be the same as in CKD to decrease cardiovascular morbidity and mortality. Whether these interventions also delay disease progression needs further study.
  4. Eur J Pharmacol. 2021 Jul 08. pii: S0014-2999(21)00476-3. [Epub ahead of print]907 174323
      The present study addresses the effect of the Rho-kinase (ROCK) inhibitor Y-27632 on the β2-adrenoceptor density and β-agonist-stimulated intracellular second messenger cAMP formation in primary equine bronchial epithelial cells (EBEC). Y-27632 significantly decreased the β2-adrenoceptor number (Bmax) without markedly affecting the receptor affinity (dissociation constant, KD) to the radioligand [125I]-iodocyanopindolol (ICYP). In contrast, Y-27632 augmented the β-agonist-stimulated intracellular cAMP production. Herein, Y-27632 markedly increased the maximal cAMP responses (Emax) (isoproterenol > epinephrine > norepinephrine) but did not shift the β-agonist concentration-effect curves to the left. The β2-selective antagonist ICI 118.551 and the β1/β2-antagonsit propranolol but not the β1-selctive antagonist CGP 20712A reversed the isoproterenol-induced cAMP formation equally in Y-27632-treated and control EBEC, suggesting the effect was merely related to the β2-subtype. These results show that Y-27632 differentially regulates the receptor density and function. Thus, these findings provide the first evidence that the functional interaction of the β2-adrenoceptor and Rho-kinase (ROCK) signaling pathways decreases the receptor expression but enhances receptor downstream cAMP formation. This differential regulation of the receptor density and function by Y-27632 should be further reconsidered with regard to the beneficial effect of the drug in asthma therapy.
    Keywords:  Bronchial epithelial cells; Equine asthma; Y-27632; cAMP; β(2)-adrenoceptors
  5. Am J Kidney Dis. 2021 Jul 07. pii: S0272-6386(21)00711-3. [Epub ahead of print]
      Massively Parallel Sequencing identifies pathogenic variants in the genes affected in Alport syndrome (COL4A3 - COL4A5) in up to 30 % of individuals with focal and segmental glomerulosclerosis (FSGS), 10 % of those with kidney failure of unknown cause and 20 % with familial IgA glomerulonephritis. FSGS associated with COL4A3 - COL4A5 variants is usually present by kidney failure onset and may develop because the abnormal glomerular membranes result in podocyte loss and secondary hyperfiltration. The association of COL4A3 - COL4A5 variants with kidney failure or IgA glomerulonephritis may be coincidental and not pathogenic. However, since some of these variants occur more often than they should by chance, some may be pathogenic. COL4A3 - COL4A5 variants are sometimes also found in cystic kidney diseases after autosomal dominant polycystic kidney disease (ADPKD) has been excluded. COL4A3 - COL4A5 variants should be suspected in individuals with FSGS, kidney failure of unknown cause, or familial IgA glomerulonephritis, especially where there is persistent haematuria, and a family history of haematuria or kidney failure.
  6. Elife. 2021 Jul 12. pii: e67828. [Epub ahead of print]10
      Pathophysiological defects in water homeostasis can lead to renal failure. Likewise, common genetic disorders associated with abnormal cytoskeletal dynamics in the kidney collecting ducts and perturbed calcium and cAMP signaling in the ciliary compartment contribute to chronic kidney failure. We show that collecting ducts in mice lacking the A-Kinase anchoring protein AKAP220 exhibit enhanced development of primary cilia. Mechanistic studies reveal that AKAP220-associated protein phosphatase 1 (PP1) mediates this phenotype by promoting changes in the stability of histone deacetylase 6 (HDAC6) with concomitant defects in actin dynamics. This proceeds through a previously unrecognized adaptor function for PP1 as all ciliogenesis and cytoskeletal phenotypes are recapitulated in mIMCD3 knock-in cells expressing a phosphatase-targeting defective AKAP220-ΔPP1 mutant. Pharmacological blocking of local HDAC6 activity alters cilia development and reduces cystogenesis in kidney-on-chip and organoid models. These findings identify the AKAP220-PPI-HDAC6 pathway as a key effector in primary cilia development.
    Keywords:  biochemistry; cell biology; chemical biology; mouse
  7. Neoplasma. 2021 Jul 14. pii: 210210N204. [Epub ahead of print]
      As a common lethal disease, cancer is now responsible for the majority of deaths worldwide and has been the single most important barrier to increasing life expectancy in the world. The pathogenesis of cancer has been the key point of cancer therapeutics research. The primary cilium, a solitary microtubule-based organelle, is considered to be an important sensor for receiving mechanical and chemical stimulation from other cells and environments; it plays an important role in a variety of signal transduction and disease processes. More importantly, the primary cilium can also function as an elaborate structure to regulate cell proliferation because ciliogenesis regulates cell division by sequestering the centriole. Recently, many new findings have suggested that the length and incidence of the primary cilium are closely connected to carcinogenesis and responses to cancer therapy. Here, we review relevant evidence proving that the primary cilium plays a key role in the occurrence and treatment of cancer. We also summarize the primary cilium-associated signaling pathways in cancer, including Wnt signaling, Hedgehog signaling, PDGFR signaling, and Notch signaling, and anticipate that targeting proteins localized in the primary cilium may be a potential anti-cancer strategy.
  8. Urologiia. 2021 Jun; 50-55
      AIM: to improve the differential diagnosis of infected cysts in patients with ADPKD and to reduce false-positive rate of MR-urography.MATERIALS AND METHODS: a total of 33 patients with ADPKD who underwent bilateral nephrectomy from 2015 to 2020 were included in the retrospective single-center study. In the group 1 (n=17) patients with histologically confirmed infected cyst (s) were included, while in the group 2 (n=16) there were patients without infected cysts. The frequency of symptoms (pain in the loin area, fever), the level of leukocytes in blood and urine, C-reactive protein (CRP) and the results of kidney MRI were compared.
    RESULTS: Pain, fever, leukocytosis, leukocyturia, and increased CRP levels were significantly associated with infected cysts. The sensitivity and specificity of MRI was 88.2% and 43.8%, respectively. The infected cysts were characterized by a significantly (p=0.004) lower value of the apparent diffusion coefficient (ADC): 0.67+/-0.2110-3 mm2/s (95% confidence interval (CI) 0.56-0.79), versus 1.2+/-0.5910-3 mm2/s (95% CI 0.89-1.5) in group 2. According to ROC analysis, the ADC value at the cut-off point was 0.8310-3 mm2/s. The frequency of infected cysts during histological examination increased when the volume of the cyst was more than 13 ml. In multivariate analysis, only the CRP level was a reliable predictor of the presence of infected cysts. ROC analysis showed that the CRP level at the cut-off point was 83 mg/L (sensitivity 70.6%, specificity 75%).
    CONCLUSION: In case of fever, pain in the loin area and high CRP level in patients with ADPKD, it is necessary to exclude infected cysts. MRI of the kidneys with the determination of the ADC level in cysts with limited diffusion on diffusion-weighted images is a highly informative method that allows to clarify the content of cysts.
    Keywords:  autosomal dominant polycystic kidney disease; end-stage renal disease; infected cyst; magnetic resonance imaging
  9. Curr Biol. 2021 Jul 08. pii: S0960-9822(21)00835-6. [Epub ahead of print]
      Ciliary extracellular vesicle (EV) shedding is evolutionarily conserved. In Chlamydomonas and C. elegans, ciliary EVs act as signaling devices.1-3 In cultured mammalian cells, ciliary EVs regulate ciliary disposal but also receptor abundance and signaling, ciliary length, and ciliary membrane dynamics.4-7 Mammalian cilia produce EVs from the tip and along the ciliary membrane.8,9 This study aimed to determine the functional significance of shedding at distinct locations and to explore ciliary EV biogenesis mechanisms. Using Airyscan super-resolution imaging in living C. elegans animals, we find that neuronal sensory cilia shed TRP polycystin-2 channel PKD-2::GFP-carrying EVs from two distinct sites: the ciliary tip and the ciliary base. Ciliary tip shedding requires distal ciliary enrichment of PKD-2 by the myristoylated coiled-coil protein CIL-7. Kinesin-3 KLP-6 and intraflagellar transport (IFT) kinesin-2 motors are also required for ciliary tip EV shedding. A big unanswered question in the EV field is how cells sort EV cargo. Here, we show that two EV cargoes- CIL-7 and PKD-2-localized and trafficked differently along cilia and were sorted to different environmentally released EVs. In response to mating partners, C. elegans males modulate EV cargo composition by increasing the ratio of PKD-2 to CIL-7 EVs. Overall, our study indicates that the cilium and its trafficking machinery act as a specialized venue for regulated EV biogenesis and signaling.
    Keywords:  C. elegans; cilia; ectosomes; exosomes; extracellular vesicles; kinesin-2; kinesin-3; myristoylation; polycystin; super-resolution microscopy
  10. Front Genet. 2021 ;12 682565
      Background: Autosomal polycystic kidney disease is distinguished into dominant (ADPKD) and recessive (ARPKD) inheritance usually caused by either monoallelic (PKD1/PKD2) or biallelic (PKHD1) germline variation. Clinical presentations are genotype-dependent ranging from fetal demise to mild chronic kidney disease (CKD) in adults. Additionally, exemptions from dominant and recessive inheritance have been reported in both disorders resulting in respective phenocopies. Here, we comparatively report three young adults with microcystic-hyperechogenic kidney morphology based on unexpected genetic alterations beyond typical inheritance.Methods: Next-generation sequencing (NGS)-based gene panel analysis and multiplex ligation-dependent probe amplification (MLPA) of PKD-associated genes, familial segregation analysis, and reverse phenotyping.
    Results: Three unrelated individuals presented in late adolescence for differential diagnosis of incidental microcystic-hyperechogenic kidneys with preserved kidney and liver function. Upon genetic analysis, we identified a homozygous hypomorphic PKHD1 missense variant causing pseudodominant inheritance in a family, a large monoallelic PKDH1-deletion with atypical transmission, and biallelic PKD1 missense hypomorphs with recessive inheritance.
    Conclusion: By this report, we illustrate clinical presentations associated with atypical PKD-gene alterations beyond traditional modes of inheritance. Large monoallelic PKHD1-alterations as well as biallelic hypomorphs of both PKD1 and PKHD1 may lead to mild CKD in the absence of prominent macrocyst formation and functional liver impairment. The long-term renal prognosis throughout life, however, remains undetermined. Increased detection of atypical inheritance challenges our current thinking of disease ontology not only in PKD but also in Mendelian disorders in general.
    Keywords:  ADPKD; ARPKD; PKD1; PKHD1; chronic kidney disease; cystic kidneys
  11. Front Cell Dev Biol. 2021 ;9 676214
      Cilia are evolutionarily highly conserved organelles with important functions in many organs. The extracellular component of the cilium protruding from the plasma membrane comprises an axoneme composed of microtubule doublets, arranged in a 9 + 0 conformation in primary cilia or 9 + 2 in motile cilia. These microtubules facilitate transport of intraflagellar cargoes along the axoneme. They also provide structural stability to the cilium, which may play an important role in sensory cilia, where signals are received from the movement of extracellular fluid. Post-translational modification of microtubules in cilia is a well-studied phenomenon, and acetylation on lysine 40 (K40) of alpha tubulin is prominent in cilia. It is believed that this modification contributes to the stabilization of cilia. Two classes of enzymes, histone acetyltransferases and histone deacetylases, mediate regulation of tubulin acetylation. Here we use a genetic approach, immunocytochemistry and behavioral tests to investigate the function of tubulin deacetylases in cilia in a zebrafish model. By mutating three histone deacetylase genes (Sirt2, Hdac6, and Hdac10), we identify an unforeseen role for Hdac6 and Sirt2 in cilia. As expected, mutation of these genes leads to increased acetylation of cytoplasmic tubulin, however, surprisingly it caused decreased tubulin acetylation in cilia in the developing eye, ear, brain and kidney. Cilia in the ear and eye showed elevated levels of mono-glycylated tubulin suggesting a compensatory mechanism. These changes did not affect the length or morphology of cilia, however, functional defects in balance was observed, suggesting that the level of tubulin acetylation may affect function of the cilium.
    Keywords:  Hdac6; Sirt2; cilia; deacetylation; zebrafish
  12. Am J Surg Pathol. 2021 Jul 15.
      Distinguishing cellular blue nevi (CBNs) and atypical CBNs from blue nevus-like melanoma (BNLM) can be diagnostically challenging. Immunohistochemistry may inform the diagnosis in a subset of cases but is not always diagnostic. Further, ancillary molecular testing is expensive and often requires significant tissue to complete. Primary cilia are cell-surface organelles with roles in signal transduction pathways and have been shown to be preserved in conventional melanocytic nevi but lost in melanoma. Immunofluorescence staining of primary cilia can be performed using a single standard-thickness formalin-fixed paraffin-embedded tissue section and has a turnaround time similar to immunohistochemistry. The percentage of tumoral melanocytes retaining a primary cilium is quantified and reported as the ciliation index. In the current study, we explored the utility of the ciliation index in a series of 31 blue nevus-like lesions, including CBNs (12), atypical CBNs (15), and BNLM (4). The average ciliation index for the CBNs was 59±18%, with a median of 60 (range: 28 to 87). The average ciliation index for atypical CBNs was 59±23, with a median of 59 (range: 20 to 93). The average ciliation index for BNLM was 4±3, with a median of 3 (range: 1 to 8). There was no significant difference in ciliation index between the CBN and atypical CBN categories. There was a significant difference between CBN and BNLM and between atypical CBNs and BNLM (P<0.001 for each). Here, we show that ciliation index is a quantitative diagnostic tool useful in the setting of blue nevus-like neoplasms, with benefits including cost and time efficiency.
  13. Elife. 2021 Jul 14. pii: e63731. [Epub ahead of print]10
      CEP78 is a centrosomal protein implicated in ciliogenesis and ciliary length control, and mutations in the CEP78 gene cause retinal cone-rod dystrophy associated with hearing loss. However, the mechanism by which CEP78 affects cilia formation is unknown. Based on a recently discovered disease-causing CEP78 p.L150S mutation, we identified the disease-relevant interactome of CEP78. We confirmed that CEP78 interacts with the EDD1-DYRK2-DDB1VPRBP E3 ubiquitin ligase complex, which is involved in CP110 ubiquitination and degradation, and identified a novel interaction between CEP78 and CEP350 that is weakened by the CEP78L150S mutation. We show that CEP350 promotes centrosomal recruitment and stability of CEP78, which in turn leads to centrosomal recruitment of EDD1. Consistently, cells lacking CEP78 display significantly increased cellular and centrosomal levels of CP110, and depletion of CP110 in CEP78-deficient cells restored ciliation frequency to normal. We propose that CEP78 functions downstream of CEP350 to promote ciliogenesis by negatively regulating CP110 levels via an EDD1-dependent mechanism.
    Keywords:  cell biology; human
  14. Sci Rep. 2021 Jul 12. 11(1): 14286
      We examined the effect of total and afferent renal denervation (RDN) on hypertension and the renin-angiotensin system (RAS) in a rodent model of juvenile-onset polycystic kidney disease (PKD). Lewis Polycystic Kidney (LPK) and control rats received total, afferent or sham RDN by periaxonal application of phenol, capsaicin or normal saline, respectively, and were monitored for 4-weeks. Afferent RDN did not affect systolic blood pressure (SBP) determined by radiotelemetry in either strain (n = 19) while total RDN significantly reduced SBP in Lewis rats 4-weeks post-denervation (total vs. sham, 122 ± 1 vs. 130 ± 2 mmHg, P = 0.002, n = 25). Plasma and kidney renin content determined by radioimmunoassay were significantly lower in LPK vs. Lewis (plasma: 278.2 ± 6.7 vs. 376.5 ± 11.9 ng Ang I/ml/h; kidney: 260.1 ± 6.3 vs. 753.2 ± 37.9 ng Ang I/mg/h, P < 0.001, n = 26). These parameters were not affected by RDN. Intrarenal mRNA expression levels of renin, angiotensinogen, angiotensin-converting enzyme (ACE)2, and angiotensin II receptor type 1a were significantly lower, whereas ACE1 expression was significantly higher in the LPK vs. Lewis (all P < 0.05, n = 26). This pattern of intrarenal RAS expression was not changed by RDN. In conclusion, RDN does not affect hypertension or the RAS in the LPK model and indicates RDN might not be a suitable antihypertensive strategy for individuals with juvenile-onset PKD.
  15. Curr Biol. 2021 Jul 05. pii: S0960-9822(21)00816-2. [Epub ahead of print]
      Microtubules are polarized intracellular polymers that play key roles in the cell, including in transport, polarity, and cell division. Across eukaryotic cell types, microtubules adopt diverse intracellular organization to accommodate these distinct functions coordinated by specific cellular sites called microtubule-organizing centers (MTOCs). Over 50 years of research on MTOC biology has focused mainly on the centrosome; however, most differentiated cells employ non-centrosomal MTOCs (ncMTOCs) to organize their microtubules into diverse arrays, which are critical to cell function. To identify essential ncMTOC components, we developed the biotin ligase-based, proximity-labeling approach TurboID for use in C. elegans. We identified proteins proximal to the microtubule minus end protein PTRN-1/Patronin at the apical ncMTOC of intestinal epithelial cells, focusing on two conserved proteins: spectraplakin protein VAB-10B/MACF1 and WDR-62, a protein we identify as homologous to vertebrate primary microcephaly disease protein WDR62. VAB-10B and WDR-62 do not associate with the centrosome and instead specifically regulate non-centrosomal microtubules and the apical targeting of microtubule minus-end proteins. Depletion of VAB-10B resulted in microtubule mislocalization and delayed localization of a microtubule nucleation complex ɣ-tubulin ring complex (γ-TuRC), while loss of WDR-62 decreased the number of dynamic microtubules and abolished γ-TuRC localization. This regulation occurs downstream of cell polarity and in conjunction with actin. As this is the first report for non-centrosomal roles of WDR62 family proteins, we expand the basic cell biological roles of this important disease protein. Our studies identify essential ncMTOC components and suggest a division of labor where microtubule growth and localization are distinctly regulated.
    Keywords:  C. elegans; MTOC; TurboID; WD40 repeat protein; differentiation; epithelial cell; microtubules; ncMTOC; spectraplakin
  16. Am J Physiol Renal Physiol. 2021 Jul 12.
      Primary cilia are widely regarded as specialized sensors in differentiated cells that have been implicated in the regulation of cell proliferation, differentiation, and viability. We previously showed that shortening of primary cilia sensitizes cultured kidney tubular cells to cisplatin-induced apoptosis. IFT88 is an essential component for ciliogenesis and maintenance. Here, we have further examined the effect of proximal tubule-specific IFT88 ablation on cisplatin-induced acute kidney injury (AKI). In the study, more severe AKI occurred in IFT88 knockout mouse than age- and sex-matched wild type mice. Mechanistically, cisplatin stimulated autophagy in kidney tubular cells as an intrinsic protective mechanism. However, renal autophagy was severely impaired in IFT88 knockout mouse. In cultured HK-2 cells, cisplatin induced more apoptosis when IFT88 was knocked down. Tat-beclin 1 peptide, a specific autophagy activator, could partially prevent IFT88-associated cell death during cisplatin treatment, although cilium length was not improved significantly. Re-expression of IFT88 partially restored autophagy in IFT88-knockdown cells and suppressed apoptosis during cisplatin treatment. Taken together, these results indicate that defective autophagy in IFT88-deficient kidney cells and tissues contributes to the exaggerated AKI following cisplatin exposure.
    Keywords:  IFT88; acute kidney injury; autophagy; cisplatin; kidney
  17. Proc Natl Acad Sci U S A. 2021 Jul 13. pii: e2102562118. [Epub ahead of print]118(28):
      Here, we report that important regulators of cilia formation and ciliary compartment-directed protein transport function in secretion polarity. Mutations in cilia genes cep290 and bbs2, involved in human ciliopathies, affect apical secretion of Cochlin, a major otolith component and a determinant of calcium carbonate crystallization form. We show that Cochlin, defective in human auditory and vestibular disorder, DFNA9, is secreted from small specialized regions of vestibular system epithelia. Cells of these regions secrete Cochlin both apically into the ear lumen and basally into the basal lamina. Basally secreted Cochlin diffuses along the basal surface of vestibular epithelia, while apically secreted Cochlin is incorporated into the otolith. Mutations in a subset of ciliopathy genes lead to defects in Cochlin apical secretion, causing abnormal otolith crystallization and behavioral defects. This study reveals a class of ciliary proteins that are important for the polarity of secretion and delineate a secretory pathway that regulates biomineralization.
    Keywords:  Cochlin; apical secretion; cep290; ear; otolith
  18. Exp Clin Transplant. 2021 Jul 16.
      We describe a case of a 55-year-old woman with polycystic kidney disease who received a living donor kidney transplant 16 years earlier and was on immunosuppressive therapy with satisfactory renal function. The donor was her mother. The patient presented with flank pain on the right side and macrohematuria, and noncontrast computed tomography and magnetic resonance imaging led to the diagnosis of tumors in the remaining right native polycystic kidney and ureter, as well as secondary retroperitoneal dissemination. We performed right radical nephrectomy and ureterectomy with extirpation of 2 metastases; the left native kidney remained intact. Histology showed squamous metaplastic changes and invasive epithelial neoplasm in the lumen of the renal pelvis and ureter with extensive squamous differentiation positive for nuclear p63 as squamous cell immunohistochemical marker. After surgery, an immunosuppressive therapy with methylprednisolone was administered, without calcineurin inhibitors and mycophenolate mofetil. Twelve months later the patient was still alive, with a glomerular filtration rate of 29 mL/min. Needs remain for further treatment modalities in patients with primary squamous cell carcinoma in nonfunctioning kidneys and improvements in imaging technique accuracy.
  19. BMC Nephrol. 2021 Jul 14. 22(1): 263
      BACKGROUND: Polycystic Kidney Disease (PKD) is a hereditary disorder that has no cure and can result in end stage kidney failure. Searching for health information online and via social media is a common phenomenon in many medical conditions. However, no recent studies have documented the information needs, online behaviours, and concerns of people with PKD. The aim of this study was to explore the information needs of individuals with PKD and their carers by documenting (i) the information needs (ii) online information health seeking behaviours (iii) the perceived challenges of living with PKD and (iv) dietary concerns.METHODS: A 17-item survey was constructed by undertaking a social listening analysis. This survey was then distributed via PKD related social media groups on Facebook. Seven groups distributed the survey with permission from the group owners. Open free text survey questions were analysed thematically using content analysis.
    RESULTS: A total of 536 respondents completed the online survey (70.9 % female, 77 % aged 35-70, 70.2 % diagnosed more than 10 years ago). The major information need expressed by participants with PKD was for dietary information. Information regarding medications, medical management and symptom control were also desired. The overarching themes arising from the free text responses to the major challenge of living with PKD included 'learning to navigate dietary ambiguities'; 'managing social, psychological and emotional needs'; and 'accepting an uncertain future'. In addition to a strong desire for practical and specific dietary information, participants expressed a need for more online information pertaining to management of fatigue, pain, complications and how to manage mental health. Online peer support was also highly regarded and desired.
    CONCLUSIONS: This study provides contemporary insights into the type of information desired by people with PKD. The results indicated that there was a strong desire for unambiguous information and guidance from health professionals to facilitate self-management, alleviate concerns, and address the complexities of living with Polycystic Kidney Disease. While diet is an important and frequently expressed need, there also remains a large demand for information on how to support psychological needs, and on medical management in order to support treatment decision making. Future work is required to develop specific, actionable and evidence-based resources for patients that are available online and through health professionals. Increased access to renal dietitians, peer support and additional training for health professionals could also improve patient-centered care and support self-management.
    Keywords:  Cross sectional study; Diet; Information needs; Patient preferences; Patient-centered care; Polycystic kidney disease; Self-management; Social listening; Thematic analysis; online survey
  20. Semin Respir Crit Care Med. 2021 Aug;42(4): 537-548
      Primary ciliary dyskinesia (PCD) is an inherited cause of bronchiectasis. The estimated PCD prevalence in children with bronchiectasis is up to 26% and in adults with bronchiectasis is 1 to 13%. Due to dysfunction of the multiple motile cilia of the respiratory tract patients suffer from poor mucociliary clearance. Clinical manifestations are heterogeneous; however, a typical patient presents with chronic productive cough and rhinosinusitis from early life. Other symptoms reflect the multiple roles of motile cilia in other organs and can include otitis media and hearing loss, infertility, situs inversus, complex congenital heart disease, and more rarely other syndromic features such as hydrocephalus and retinitis pigmentosa. Awareness, identification, and diagnosis of a patient with PCD are important for multidisciplinary care and genetic counseling. Diagnosis can be pursued through a multitest pathway which includes the measurement of nasal nitric oxide, sampling the nasal epithelium to assess ciliary function and structure, and genotyping. Diagnosis is confirmed by the identification of a hallmark ultrastructural defect or pathogenic mutations in one of > 45 PCD causing genes. When a diagnosis is established management is centered around improving mucociliary clearance through physiotherapy and treatment of infection with antibiotics. The first international randomized controlled trial in PCD has recently been conducted showing azithromycin is effective in reducing exacerbations. It is likely that evidence-based PCD-specific management guidelines and therapies will be developed in the near future. This article examines prevalence, clinical features, diagnosis, and management of PCD highlighting recent advances in basic science and clinical care.
  21. Bio Protoc. 2021 Jun 05. 11(11): e4041
      Over the years, studying the ultrastructure of the eukaryotic cilia/flagella using electron microscopy (EM) has contributed significantly toward our understanding of ciliary function. Major complexes in the cilia, such as inner and outer dynein arms, radial spokes, and dynein regulatory complexes, were originally discovered by EM. Classical resin-embedding EM or cryo-electron tomography can be performed directly on the isolated cilia or in some cases, cilia directly attached to the cell body. Recently, single particle cryo-EM has emerged as a powerful structural technique to elucidate high-resolution structures of macromolecular complexes; however, single particle cryo-EM requires non-overlapping complexes, i.e., the doublet microtubule of the cilia. Here, we present a protocol to separate the doublet microtubule from the isolated cilia bundle of two species, Tetrahymena thermophila and Chlamydomonas reinhardtii, using ATP reactivation and sonication. Our approach produces good distribution and random orientation of the doublet microtubule fragments, which is suitable for single particle cryo-EM analysis.
    Keywords:  Chlamydomonas reinhardtii; Cilia; Cryo-EM; Doublet microtubule; Flagella; Mass spectrometry; Tetrahymena thermophila
  22. Sci Prog. 2021 Jul-Sep;104(3):104(3): 368504211025921
      Synthetic cilia-regulated transports through micro and nanofluidic devices guarantee an efficient delivery of drugs and other biological substances. Entropy analysis of cilia stimulated transport of thermally radiated hybrid nanofluid through an electroosmotic pump is conducted in this study. Joint effects of applied Lorentz force and Ohmic heating on the intended stream are also studied. Metachronal arrangements of cilia field coating channel inner side, are liable to generate current in the fluid. After using the lubrication and the Debye-Huckel estimations, numerical solutions of the envisioned problem are obtained. For pressure rise per metachronal wavelength, the pressure gradient is numerically integrated. The analysis reveals that high electric potential results in reducing the heat transfer effects in the flow system. The enhancement of flow is noticed near the channel surface for higher electroosmotic parameters. The irreversibility in the channel decreases when the Helmholtz-Smoluchowski velocity is applied in the opposite direction of the flow and thus produces the fluid friction irreversibility.
    Keywords:  Entropy analysis; Williamson hybrid nanofluid; electroosmotic ciliary flow; magnetic field; thermal radiations
  23. Hum Reprod. 2021 Jul 16. pii: deab161. [Epub ahead of print]
      STUDY QUESTION: Can a combination of the focussed protein kinase assays and a wide-scale proteomic screen pinpoint novel, clinically relevant players in decidualization in vitro and in vivo?SUMMARY ANSWER: Rho-dependent protein kinase (ROCK) activity is elevated in response to the combined treatment with progesterone and 8-Br-cAMP during in vitro decidualization, mirrored by increase of ROCK2 mRNA and protein levels and the phosphorylation levels of its downstream target Cofilin-1 (CFL1) in secretory versus proliferative endometrium.
    WHAT IS KNOWN ALREADY: Decidualization is associated with extensive changes in gene expression profile, proliferation, metabolism and morphology of endometrium, yet only a few underlying molecular pathways have been systematically explored. In vitro decidualization of endometrial stromal cells (ESCs) can be reportedly induced using multiple protocols with variable physiological relevance. In our previous studies, cyclic AMP (cAMP)/cAMP-dependent protein kinase (PKA)/prolactin axis that is classically upregulated during decidualization showed dampened activation in ESCs isolated from polycystic ovary syndrome (PCOS) patients as compared to controls.
    STUDY DESIGN, SIZE, DURATION: In vitro decidualization studies were carried out in passage 2 ESCs isolated from controls (N = 15) and PCOS patients (N = 9). In parallel, lysates of non-cultured ESCs isolated from proliferative (N = 4) or secretory (N = 4) endometrial tissue were explored. The observed trends were confirmed using cryo-cut samples of proliferative (N = 3) or secretory endometrium (N = 3), and in proliferative or secretory full tissue samples from controls (N = 8 and N = 9, respectively) or PCOS patients (N = 10 for both phases).
    PARTICIPANTS/MATERIALS, SETTING, METHODS: The activities of four target kinases were explored using kinase-responsive probes and selective inhibitors in lysates of in vitro decidualized ESCs and non-cultured ESCs isolated from tissue at different phases of the menstrual cycle. In the latter lysates, wide-scale proteomic and phosphoproteomic studies were further carried out. ROCK2 mRNA expression was explored in full tissue samples from controls or PCOS patients. The immunofluorescent staining of phosphorylated CFL1 was performed in full endometrial tissue samples, and in the in vitro decidualized fixed ESCs from controls or PCOS patients. Finally, the cellular migration properties were explored in live in vitro decidualized ESCs.
    MAIN RESULTS AND THE ROLE OF CHANCE: During in vitro decidualization, the activities of PKA, protein kinase B (Akt/PKB), and ROCK are increased while the activity of casein kinase 2 (CK2) is decreased; these initial trends are observable after 4-day treatment (P < 0.05) and are further augmented following the 9-day treatment (P < 0.001) with mixtures containing progesterone and 8-Br-cAMP or forskolin. The presence of progesterone is necessary for activation of ROCK, yet it is dispensable in the case of PKA and Akt/PKB; in comparison to controls, PCOS patient-derived ESCs feature dampened response to progesterone. In non-cultured ESCs isolated from secretory vs proliferative phase tissue, only activity of ROCK is increased (P < 0.01). ROCK2 protein levels are slightly elevated in secretory versus proliferative ESCs (relative mean standard deviation < 50%), and ROCK2 mRNA is elevated in mid-secretory versus proliferative full tissue samples (P < 0.05) obtained from controls but not PCOS patients. Activation of ROCK2 downstream signalling results in increase of phospho-S3 CFL1 in secretory endometrium (P < 0.001) as well as in vitro decidualized ESCs (P < 0.01) from controls but not PCOS patients. ROCK2-triggered alterations in the cytoskeleton are reflected by the significantly decreased motility of in vitro decidualized ESCs (P < 0.05).
    LARGE SCALE DATA: Proteomic and phosphoproteomic data are available via ProteomeXchange with identifier PXD026243.
    LIMITATIONS, REASONS FOR CAUTION: The number of biological samples was limited. The duration of protocol for isolation of non-cultured ESCs from tissue can potentially affect phosphorylation pathways in cells, yet the possible artefacts were minimized by the identical treatment of proliferative and secretory samples.
    WIDER IMPLICATIONS OF THE FINDINGS: The study demonstrated the benefits of combining the focussed kinase activity assay with wide-scale phosphoproteomics and showed the need for detailed elaboration of the in vitro decidualization protocols. ROCK was identified as the novel target of interest in decidualization, which requires closer attention in further studies-including the context of decidualization-related subfertility and infertility.
    STUDY FUNDING/COMPETING INTEREST(S): This study was funded by the Estonian Ministry of Education and Research, and the Estonian Research Council (PRG1076, PRG454, PSG230 and PSG608), Enterprise Estonia (EU48695), Horizon 2020 innovation grant (ERIN, Grant no. EU952516) of the European Commission, the COMBIVET ERA Chair, H2020-WIDESPREAD-2018-04 (Grant agreement no. 857418), the Academy of Finland (Project grants 315921 and 321763), the Finnish Medical Foundation and The Sigrid Juselius Foundation. The authors confirm that they have no conflict of interest with respect to the content of this article.
    Keywords:  8-Br-cAMP; Rho-dependent protein kinase; cAMP-dependent protein kinase; casein kinase 2; decidualization; endometrial stromal cells; phospho-cofilin; polycystic ovary syndrome; progesterone; protein kinase B
  24. J Cell Biol. 2021 Sep 06. pii: e202007177. [Epub ahead of print]220(9):
      Epithelial cells lining mucosal surfaces distinctively express the inflammatory bowel disease risk gene INAVA. We previously found that INAVA has dual and competing functions: one at lateral membranes where it affects mucosal barrier function and the other in the cytosol where INAVA enhances IL-1β signal transduction and protein ubiquitination and forms puncta. We now find that IL-1β-induced INAVA puncta are biomolecular condensates that rapidly assemble and physiologically resolve. The condensates contain ubiquitin and the E3 ligase βTrCP2, and their formation correlates with amplified ubiquitination, suggesting function in regulation of cellular proteostasis. Accordingly, a small-molecule screen identified ROS inducers, proteasome inhibitors, and inhibitors of the protein folding chaperone HSP90 as potent agonists for INAVA condensate formation. Notably, inhibitors of the p38α and mTOR pathways enhanced resolution of the condensates, and inhibitors of the Rho-ROCK pathway induced INAVA's competing function by recruiting INAVA to newly assembled intercellular junctions in cells where none existed before.
  25. Sci Rep. 2021 Jul 14. 11(1): 14443
      Smoking has been associated with renal disease progression in ADPKD but the underlying deleterious mechanisms and whether it specifically worsens the cardiac phenotype remain unknown. To investigate these matters, Pkd1-deficient cystic mice and noncystic littermates were exposed to smoking from conception to 18 weeks of age and, along with nonexposed controls, were analyzed at 13-18 weeks. Renal cystic index and cyst-lining cell proliferation were higher in cystic mice exposed to smoking than nonexposed cystic animals. Smoking increased serum urea nitrogen in cystic and noncystic mice and independently enhanced tubular cell proliferation and apoptosis. Smoking also increased renal fibrosis, however this effect was much higher in cystic than in noncystic animals. Pkd1 deficiency and smoking showed independent and additive effects on reducing renal levels of glutathione. Systolic function and several cardiac structural parameters were also negatively affected by smoking and the Pkd1-deficient status, following independent and additive patterns. Smoking did not increase, however, cardiac apoptosis or fibrosis in cystic and noncystic mice. Notably, smoking promoted a much higher reduction in body weight in Pkd1-deficient than in noncystic animals. Our findings show that smoking aggravated the renal and cardiac phenotypes of Pkd1-deficient cystic mice, suggesting that similar effects may occur in human ADPKD.