bims-bicyki Biomed News
on Bicaudal-C1 and interactors in cystic kidney disease
Issue of 2022–02–13
twenty-one papers selected by
Céline Gagnieux, École Polytechnique Fédérale de Lausanne



  1. Gastroenterology. 2022 Feb 08. pii: S0016-5085(22)00122-6. [Epub ahead of print]
      
    Keywords:  autosomal dominant polycystic kidney disease; colonoscopy; compression
    DOI:  https://doi.org/10.1053/j.gastro.2022.01.055
  2. Nephrol Dial Transplant. 2021 Nov 19. pii: gfab312. [Epub ahead of print]
      The approval of the vasopressin V2-receptor antagonist tolvaptan - based on the landmark TEMPO 3:4 trial - has marked a transformation in the management of autosomal dominant polycystic kidney disease (ADPKD). This development has advanced patient care in ADPKD from general measures to prevent progression of chronic kidney disease to targeting disease specific mechanisms. However, considering the long-term nature of this treatment as well as potential side effects, evidence-based approaches to initiate treatment only in patients with rapidly progressing disease are crucial. In 2016, the position statement issued by the ERA was the first society-based recommendation on the use of tolvaptan and has served as a widely-used decision-making tool for nephrologists. Since then, considerable practical experience regarding the use of tolvaptan in ADPKD has accumulated. More importantly, additional data from REPRISE, a second randomized clinical trial (RCT) examining the use of tolvaptan in later stage disease has added important evidence to the field, as have post-hoc studies of these RCTs. To incorporate this new knowledge, we provide an updated algorithm to guide patient selection for treatment with tolvaptan and add practical advice for its use.
    Keywords:  ADPKD; polycystic kidney disease; position statement; tolvaptan; vasopressin V2 receptor antagonist
    DOI:  https://doi.org/10.1093/ndt/gfab312
  3. J Med Chem. 2022 Feb 10.
      Autosomal dominant polycystic kidney disease (ADPKD) is the most prevalent monogenic human disease, but to date, only one therapy (tolvaptan) is approved to treat kidney cysts in ADPKD patients. Cyclin-dependent kinase 5 (CDK5), an atypical member of the cyclin-dependent kinase family, has been implicated as a target for treating ADPKD. However, no compounds have been disclosed to date that selectively inhibit CDK5 while sparing the broader CDK family members. Herein, we report the discovery of CDK5 inhibitors, including GFB-12811, that are highly selective over the other tested kinases. In cellular assays, our compounds demonstrate CDK5 target engagement while avoiding anti-proliferative effects associated with inhibiting other CDKs. In addition, we show that the compounds in this series exhibit promising in vivo PK profiles, enabling their use as tool compounds for interrogating the role of CDK5 in ADPKD and other diseases.
    DOI:  https://doi.org/10.1021/acs.jmedchem.1c02069
  4. JFMS Open Rep. 2022 Jan-Jun;8(1):8(1): 20551169211070991
       Objectives: This study was aimed at detecting feline autosomal dominant polycystic kidney disease in a population of Persian and Persian-related breeds by a molecular method in Iran.
    Methods: Buccal swab samples were collected from 47 cats and examined with a touchdown PCR method. Additionally, partial sequencing was performed in two cats with bilateral renal cysts.
    Results: Twenty-two cats (46.8%) were diagnosed as heterozygous for this mutation. Sequence analysis of two cats showed C to A point mutation in the PKD1 gene, as in previous studies.
    Conclusions and relevance: Prevalence of this disease is high in Iran, highlighting the need for molecular screening tests before including cats in breeding programmes.
    Keywords:  Iran; Persian cats; Polycystic kidney disease; touchdown PCR
    DOI:  https://doi.org/10.1177/20551169211070991
  5. Clin Nephrol. 2022 Feb 10.
      Deletions involving the TSC2 and PKD1 genes lead to tuberous sclerosis complex (TSC) and autosomal dominant polycystic kidney disease (ADPKD), which is known as TSC2-PKD1 contiguous gene deletion syndrome (PKDTS). PKDTS leads to severe symptoms and death. There are few reported cases of PKDTS, the phenotypic descriptions are poor, and detailed statistics and descriptions of the time of onset and prognosis of PKDTS are lacking. This is the first study to report on the clinical data of PKDTS patients in China. We analyzed all cases including Chinese individuals and summarized the clinical manifestations and genetic characteristics. Our study was the first to use a combination of exome sequencing and multiplex ligation-dependent probe amplification (MLPA) to screen and diagnose PKDTS. We found that many PKDTS patients have the following: multiple renal cysts; angiofibromas (≥ 3) or fibrous cephalic plaque; subependymal nodules; seizures; intellectual disability. PKDTS develops into polycystic kidney disease from before birth to 17 years old and the time of occurrence of end-stage renal disease or dialysis was 21.62 ± 12.87 years of age, which was significantly earlier than in ADPKD caused by PKD1 mutation. Compared with non-Chinese individuals of diverse ancestry, Chinese people have significant differences in the clinical characteristics, including ungual fibromas (≥ 2), and shagreen patch. Five novel large deletions were identified in Chinese. We found no relationship between the clinical phenotype and the genotype. We combined exome sequencing with MLPA to develop a diagnostic method for PKDTS.
    DOI:  https://doi.org/10.5414/CN110476
  6. J Bras Nefrol. 2022 Jan 31. pii: S0101-28002022005005401. [Epub ahead of print]
       INTRODUCTION: Endothelial nitric oxide synthase (eNOS) genes have been implicated in renal hemodynamics as potent regulators of vascular tone and blood pressure. It has been linked to a reduction in plasma nitric oxide levels. Several studies have recently been conducted to investigate the role of NOS3 gene polymorphisms and end-stage renal disease (ESRD). However, the results are still unclear and the mechanisms are not fully defined. As a result, we conducted a meta-analysis to examine the relationship between NOS3 gene polymorphism and ESRD in autosomal polycystic kidney disease (ADPKD) patients.
    METHODS: To assess the relationship between NOS3 gene polymorphism and ESRD, relevant studies published between September 2002 and December 2020 were retrieved from the PubMed (Medline), EMBASE, Google Scholar, and Web of Science databases. The pooled odds ratio (OR) and 95 % confidence interval (CI) were calculated using a fixed-effect model. To assess the heterogeneity of studies, we used Cochrane's Q test and the Higgins and Thompson I2 statistics.
    RESULTS: Our meta-analysis of 13 studies showed that the presence of the two NOS3 gene polymorphisms significantly increased ESRD risk in ADPKD patients with 4a/b gene polymorphism (aa+ab vs. bb: OR=1.95, 95% CI=1.24-3.09, p=0.004). In addition, no significant association was found between the NOS3 894G>T (Glu298Asp) polymorphism and the risk of ESRD in ADPKD patients (GT+TT vs. GG: OR=1.21, 95% CI=0.93-1.58, p=0.157). There was no evidence of publication bias.
    CONCLUSIONS: The findings of the current meta-analysis suggest that NOS3 intron 4a/b polymorphism plays a vital role in the increasing risk of ESRD in ADPKD patients.
    DOI:  https://doi.org/10.1590/2175-8239-JBN-2021-0089
  7. BMC Biol. 2022 Feb 10. 20(1): 42
       BACKGROUND: Primary cilia are sensory organelles crucial for organ development. The pivotal structure of the primary cilia is a microtubule that is generated via tubulin polymerization reaction that occurs in the basal body. It remains to be elucidated how molecules with distinct physicochemical properties contribute to the formation of the primary cilia.
    RESULTS: Here we show that brain expressed X-linked 1 (Bex1) plays an essential role in tubulin polymerization and primary cilia formation. The Bex1 protein shows the physicochemical property of being an intrinsically disordered protein (IDP). Bex1 shows cell density-dependent accumulation as a condensate either in nucleoli at a low cell density or at the apical cell surface at a high cell density. The apical Bex1 localizes to the basal body. Bex1 knockout mice present ciliopathy phenotypes and exhibit ciliary defects in the retina and striatum. Bex1 recombinant protein shows binding capacity to guanosine triphosphate (GTP) and forms the condensate that facilitates tubulin polymerization in the reconstituted system.
    CONCLUSIONS: Our data reveals that Bex1 plays an essential role for the primary cilia formation through providing the reaction field for the tubulin polymerization.
    Keywords:  Bex1; Intrinsically disordered protein (IDP); Juvenility-associated genes (JAGs); Primary cilia; Tubulin polymerization
    DOI:  https://doi.org/10.1186/s12915-022-01246-x
  8. J Biol Chem. 2022 Feb 04. pii: S0021-9258(22)00126-0. [Epub ahead of print] 101686
      In humans, ciliary dysfunction causes ciliopathies, which present as multiple organ defects, including developmental and sensory abnormalities. Sdccag8 is a centrosomal/basal body protein essential for proper cilia formation. Gene mutations in SDCCAG8 have been found in patients with ciliopathies manifesting a broad spectrum of symptoms, including hypogonadism. Among these mutations, several that are predicted to truncate the SDCCAG8 carboxyl (C)-terminus are also associated with such symptoms; however, the underlying mechanisms are poorly understood. In the present study, we identified the Sdccag8 C-terminal region (Sdccag8-C) as a module that interacts with the ciliopathy proteins, Ick/Cilk1 and Mak, which were shown to be essential for the regulation of ciliary protein trafficking and cilia length in mammals in our previous studies. We found that Sdccag8-C is essential for Sdccag8 localization to centrosomes and cilia formation in cultured cells. We then generated a mouse mutant in which Sdccag8-C was truncated (Sdccag8ΔC/ΔC mice) using a CRISPR-mediated stop codon knock-in strategy. In Sdccag8ΔC/ΔC mice, we observed abnormalities in cilia formation and ciliopathy-like organ phenotypes, including cleft palate, polydactyly, retinal degeneration, and cystic kidney, which partially overlapped with those previously observed in Ick- and Mak-deficient mice. Furthermore, Sdccag8ΔC/ΔC mice exhibited a defect in spermatogenesis, which was a previously uncharacterized phenotype of Sdccag8 dysfunction. Together, these results shed light on the molecular and pathological mechanisms underlying ciliopathies observed in patients with SDCCAG8 mutations, and may advance our understanding of protein-protein interaction networks involved in cilia development.
    Keywords:  CRISPR/Cas; cilia; intestinal cell kinase/ciliogenesis-associated kinase 1; kidney; male germ cell-associated kinase; mouse; retina; serologically defined colon cancer antigen 8; sonic hedgehog; spermatogenesis
    DOI:  https://doi.org/10.1016/j.jbc.2022.101686
  9. Comput Math Methods Med. 2022 ;2022 5823720
      The objective of this study was to explore the accuracy of low-dosage computed tomography (CT) images based on the expectation maximization algorithm denoising algorithm (EM algorithm) in the detection and diagnosis of renal dysplasia, so as to provide reasonable research basis for accuracy improvement of clinical diagnosis of renal dysplasia. 120 patients with renal dysplasia in hospital were randomly selected as the research objects, and they were divided into two groups by random number method, with 60 patients in each group. The low-dosage CT images of patients in the control group were not processed (nonalgorithm group), and the low-dosage CT images of patients in the observation group were denoised using the EM algorithm (algorithm group). In addition, it was compared with the results of the comprehensive diagnosis (gold standard) to analyze the accuracy of the diagnosis of the two groups of patients and the consistency with the results of the pathological diagnosis. The results were compared with those of the comprehensive diagnosis (gold standard) to analyze the accuracy of the diagnosis of the two groups of patients. The results showed that the peak signal-to-noise ratio (PSNR) (15.9 dB) of the EM algorithm was higher than the regularized adaptive matching pursuit (RAMP) algorithm (1.69 dB) and the mean filter (4.3 dB) (P < 0.05). The time consumption of EM algorithm (21 s) was shorter than that of PWLS algorithm (34 s) and MS-PWLS algorithm (39 s) (P < 0.05). The diagnosis accuracy of dysplasia of single kidney, absence of single kidney, horseshoe kidney, and duplex kidney was obviously higher in the algorithm group than the control group (P < 0.05), which were 66.67% vs. 90%, 60% vs. 88.89%, 71.42% vs. 100%, and 60% vs. 88.89%, respectively. The incidence of hypertension in patients with autosomal dominant polycystic kidney disease (ADPKD) (56.77%) was much higher than that of the other diseases (P < 0.05). After denoising by the EM algorithm, low-dosage CT image could improve the diagnostic accuracy of several types of renal dysplasia except ADPKD, showing certain clinical application value. In addition, ADPKD was easy to cause hypertension.
    DOI:  https://doi.org/10.1155/2022/5823720
  10. J Avian Med Surg. 2022 Jan;35(4): 464-474
      This case series describes polycystic kidney disease in 3 (2 male, 1 female) 2-month-old, juvenile rainbow lorikeets (Trichoglossus moluccanus). The lorikeets diagnosed with polycystic kidney disease were the progeny of full sibling parents that were being intentionally line bred for the purpose of establishing a rainbow lorikeet with the blue color mutation. Clinically the juvenile lorikeets were presented with clinical signs of lethargy, dehydration, regurgitation, anorexia, polyuria, and pelvic limb paresis. Multiple abnormalities were identified on the complete blood count and plasma biochemistry panel, including a normocytic normochromic nonregenerative anemia, hyperuricemia, hyperphosphatemia, hypercalcemia, and azotemia. Severe renal dysfunction was diagnosed in all birds on the basis of clinical presentation, physical examination, and complete blood count and plasma biochemistry results. Radiographically marked renomegaly was noted in one of the cases. Although intensive critical care and supportive therapy was provided, 1 lorikeet died, and the remaining 2 were euthanatized because of client financial constraints and a rapid deterioration of their clinical condition associated with severe renal dysfunction. Postmortem pathology results found that all birds had marked renomegaly, visceral gout, and polycystic kidney disease. Because of the age of the birds and the line breeding within this group of lorikeets, the disease was believed to be inherited. Polycystic kidney disease should be considered as a possible differential diagnosis in juvenile psittacine birds with a history of line breeding when presented with severe renal dysfunction. From the current case series, polycystic kidney disease appears to carry a grave prognosis in juvenile rainbow lorikeets.
    DOI:  https://doi.org/10.1647/20-00023
  11. J Cell Sci. 2022 Feb 08. pii: jcs.259201. [Epub ahead of print]
      The mucociliary clearance, which is conducted by the beating cilia cooperating with the surface mucous layer, is a major host defense mechanism of the airway epithelium. Ezrin, a crosslinker between membrane proteins and actin cytoskeleton, is located in microvilli and around the basal bodies in airway ciliary cells. It is also likely that ezrin may play the important role of apical localization of β2-adrenergic receptor (β2AR) in airway ciliary cells. Here we studied the physiological roles of ezrin by using the trachea and airway epithelial cells prepared from the ezrin-knockdown (Vil2kd/kd) mice. The trachea and airway ciliary cells of Vil2kd/kd mice represented normal morphology and basal body orientation, suggesting that ezrin is not directly involved in development and planer cell polarity of cilia. Procaterol stimulates ciliary beating (frequency and amplitude) via β2AR in the airway ciliary cells. In the Vil2kd/kd mice, airway ciliary beating stimulated with procaterol was partly inhibited due to the impairment of cell surface expression of β2AR. These results suggest that ezrin regulates the beating of airway ciliary cells by promoting the apical surface localization of β2AR.
    Keywords:  Airway; Basal body; Cilia; Cytoskeletal protein; β2AR
    DOI:  https://doi.org/10.1242/jcs.259201
  12. Sci Rep. 2022 Feb 11. 12(1): 2375
      Primary ciliary dyskinesia (PCD) is a rare autosomal recessive condition often presenting with chronic respiratory infections in early life. Transmission electron microscopy (TEM) is used to detect ciliary ultrastructural defects. In this study, we aimed to assess ciliary ultrastructural defects using quantitative methods on TEM to identify its diagnostic role in confirming PCD. Nasal samples of 67 patients, including 37 females and 30 males (20.3 ± 10.7 years old), with suspected PCD symptoms were examined by TEM. The most common presentations were bronchiectasis: 26 (38.8%), chronic sinusitis: 23 (34.3%), and recurrent lower respiratory infections: 21 (31.3%). Secondary ciliary dyskinesia, including compound cilia (41.4%) and extra-tubules (44.3%), were the most prevalent TEM finding. Twelve patients (17.9%) had hallmark diagnostic criteria for PCD (class 1) consisting of 11 (16.4%) outer and inner dynein arm (ODA and IDA) defects and only one concurrent IDA defect and microtubular disorganization. Also, 11 patients (16.4%) had probable criteria for PCD (class 2), 26 (38.8%) had other defects, and 18 (26.9%) had normal ciliary ultrastructure. Among our suspected PCD patients, the most common ultrastructural ciliary defects were extra-tubules and compound cilia. However, the most prevalent hallmark diagnostic defect confirming PCD was simultaneous defects of IDA and ODA.
    DOI:  https://doi.org/10.1038/s41598-022-06370-w
  13. J Cell Physiol. 2022 Feb 11.
      Cilia assembly and centriole duplication are closely coordinated with cell cycle progression, and inhibition of cilia disassembly impedes cell cycle progression. The centrosomal protein trichoplein (TCHP) has been shown to promote cell cycle progression in the G1 -S phase by disassembling cilia. In this study, we showed that deletion of TCHP not only prevented the progression to the S phase but also resulted in cell cycle exit and entrance into G0 phase. Surprisingly, we found that loss of TCHP-induced G0 arrest could not be reversed by blocking the assembly of cilia. In cells without IFT20 or CEP164, two genes encoding key factors for ciliogenesis, depletion of TCHP still led to G0 arrest. Mechanistically, we also found that TCHP depletion-induced cell cycle arrest was not mediated through a centrosome surveillance mechanism, but inhibition of Rb or concomitant inhibition of both Rb and p53 signaling pathways was required to reverse the cell cycle phenotype. In conclusion, our study provides new insights into the function of TCHP in cell cycle progression.
    Keywords:  cell cycle; centrosome; cilia; trichoplein
    DOI:  https://doi.org/10.1002/jcp.30693
  14. Hum Mol Genet. 2022 Feb 06. pii: ddac027. [Epub ahead of print]
      Mutations in genes that lead to dysfunctional cilia can cause a broad spectrum of human disease phenotypes referred to as ciliopathies. Many ciliopathy-associated proteins are localized to the evolutionary conserved ciliary transition zone (TZ) subdomain. We identified biallelic missense and nonsense mutations in the gene encoding the transmembrane protein TMEM218 in unrelated patients with features related to Bardet-Biedl, Joubert and Meckel-Gruber syndrome and characterized TMEM218 as a major component of the ciliary TZ module. Co-immunoprecipitation assays resulted in physical interaction of TMEM218 with the MKS module member TMEM67/Meckelin that was significantly reduced by the TMEM218 missense change harboured by one of our patients. We could further validate its pathogenicity by functional in vivo analysis in zebrafish (Danio rerio) as a well-established vertebrate model for ciliopathies. Notably, ciliopathy-related phenotypes were most prominent by genetic interactions with the NPHP module component Nphp4. Conclusively, we describe TMEM218 as a new disease gene for patients with a wide spectrum of syndromic ciliopathy phenotypes and provide evidence for a synergistic interaction of TMEM218 and the NPHP module crucial for proper ciliary function.
    DOI:  https://doi.org/10.1093/hmg/ddac027
  15. J Cell Physiol. 2022 Feb 06.
      The microtubular scaffold of motile cilia-the axoneme, is decorated with dynein arms, which are large multiprotein complexes essential for ciliary motility. Dynein arms are arranged along the length of the axoneme in a precise repeating pattern, converting chemical energy from ATP hydrolysis into ciliary mechanical movement. How these complicated molecular machines are assembled coordinately and accurately, starting from mere polypeptide chains in the cytoplasm, remains a fascinating yet perplexing question. Rapidly emerging evidence, from multiple studies carried out with different model organisms and with various methodologies, has highlighted the existence of a dedicated assembly pathway. Here, we summarize recent progress made in clarifying the axonemal dynein arm assembly process, focusing on individual assembly steps, including cytoplasmic preassembly, intraflagellar transport, and axonemal docking.
    Keywords:  dynein arm assembly; dynein arms; motile cilia
    DOI:  https://doi.org/10.1002/jcp.30689
  16. Acta Biochim Biophys Sin (Shanghai). 2022 Jan 25. 54(2): 1-11
      Tendon injuries are common clinical issues resulted from tissue overuse and age-related degeneration. Previous sutdies have suggested that exosomes secreted by mesenchymal stem cells (MSCs) contribute to tissue injury repair. Here, we provide evidence for a critical role of human umbilical cord mesenchymal stem cell (hucMSC)-derived exosomes in reducing tendon injury by activating the RhoA signaling. Treatment of primary injured tenocytes with hucMSC exosomes increases cell proliferation and invasion, which correlates with increased RhoA activity. RhoA mediates the effects of hucMSC exosomes, as treatment of primary injured tenocytes with the RhoA inhibitor, CCG-1423, abolishes the effects of hucMSC exosomes on cell proliferation and invasion. Mechanistically, we observe that hucMSC exosomes induce the expression of a microRNA, miR-27b-3p, which targets and suppresses ARHGAP5, a negative regulator of RhoA. Consistent with this observation, ARHGAP5 overexpression suppresses the effects of hucMSC exosomes on cell proliferation and invasion, while knockdown of ARHGAP5 rescues these effects. Finally, we demonstrate the functional significance of our findings using an Achilles tendon injury model and show that treatment with exosomes reduces tendon injury in rats, which correlates with increased RhoA activity and reduced ARHGAP5 expression. Taken together, our findings highlight a critical role of hucMSC exosomes in reducing tendon injury via miR-27b-3p-mediated suppression of ARHGAP5, resulting in RhoA activation, and leading to increased cell proliferation and invasion of primary injured tenocytes.
    Keywords:  ARHGAP5; RhoA; exosomes; human umbilical cord mesenchymal stem cells; miR-27b-3p
    DOI:  https://doi.org/10.3724/abbs.2021026
  17. J Hum Genet. 2022 Feb 09.
      Nephronophthisis is an autosomal-recessive kidney disease that is caused by abnormalities in primary cilia. Nephronophthisis-related ciliopathies (NPHP-RCs) are a common cause of end-stage kidney disease (ESKD) in children and adolescents. NPHP-RCs are often accompanied by extrarenal manifestations, including intellectual disability, retinitis pigmentosa, or polydactyly. Although more than 100 causative genes have been identified, its diagnosis is difficult because the clinical features of each mutation often overlap. From September 2010 to August 2021, we performed genetic analysis, including next-generation sequencing (NGS), in 574 probands with kidney dysfunction and retrospectively studied cases genetically diagnosed with NPHP-RCs. RESULTS: We detected mutations related to NPHP-RCs in 93 patients from 83 families. Members of 60 families were diagnosed using NGS, and the mutations and the corresponding number of families are as follows: NPHP1 (24), NPHP3 (10), OFD1 (7), WDR35 (5), SDCCAG8 (4), BBS10 (3), TMEM67 (3), WDR19 (3), BBS1 (2), BBS2 (2), IFT122 (2), IFT140 (2), IQCB1 (2), MKKS (2), SCLT1 (2), TTC21B (2), ALMS1 (1), ANKS6 (1), BBS4 (1), BBS12 (1), CC2D2A (1), DYNC2H1 (1), IFT172 (1), and MAPKBP1 (1). A total of 39 cases (41.9%) progressed to ESKD at the time of genetic analysis, whereas 58 cases (62.3%) showed extrarenal manifestations, the most common being developmental delay, intellectual disability, and autism spectrum disorder in 44 patients. Comprehensive genetic analysis using NGS is useful for diagnosing patients with NPHP-RCs.
    DOI:  https://doi.org/10.1038/s10038-022-01020-5
  18. Carcinogenesis. 2022 Feb 11. pii: bgac014. [Epub ahead of print]
      Renal cell carcinoma (RCC) is characterized by substantial vasculatures and increased fluid movement in tumor microenvironment, and the fluid shear stress modulates malignance, extravasation and metastatic seeding of tumor cells. However, the precise mechanism remains largely unclear. In this study, we found that low shear stress induced the Yes-associated protein (YAP1) activation and nuclear localization in RCC cells, as well as the downregulation of phosphorylated YAP1 at Ser127. Moreover, inhibition of ROCK or RhoA partially abolished YAP1 accumulation in the nucleus, and targeting YAP1 activation by small molecular inhibitor or genetic manipulation decreased the low shear stress-induced epithelial-mesenchymal transition (EMT) of RCC cells, and led to a decreased expression of N-cadherin as accompanied by downregulation of Snail1 and Twist, accompanied by high shear stress-induced cell apoptosis. Salvianolic acid B, an aqueous component of danshen (Salvia miltiorrhiza), inhibited YAP1 and Hippo signaling activation, and abrogated low shear stress-induced EMT as a consequence. Taken together, our study suggests YAP1 is a fluid mechanosensor that transforms mechanical stimuli to cell signals, thereby facilitates anoikis resistance and tumor metastasis.
    Keywords:  Epithelial-mesenchymal transition; Renal cell carcinoma; Shear stress; YAP1
    DOI:  https://doi.org/10.1093/carcin/bgac014
  19. Liver Int. 2022 Feb 07.
       BACKGROUND & AIM: Polycystic liver disease is related to hepatomegaly which causes an increased mechanical pressure on the abdominal wall. This may lead to abdominal wall herniation. We set out to establish the prevalence of abdominal wall hernia in polycystic liver disease and explore risk factors.
    METHODS: In this cross-sectional cohort study we assessed the presence of abdominal wall hernias from polycystic liver disease patients with at least 1 abdominal computed tomography or magnetic resonance imaging scan. Abdominal wall hernia presence on imaging was independently evaluated by two researchers. Data on potential risk factors were extracted from clinical files.
    RESULTS: We included 484 patients of which 40.1% (n=194) had an abdominal wall hernia. We found a clear predominance of umbilical hernias (25.8%, n=125) while multiple hernias were present in 6.2% (n=30). Using multivariate analysis, male sex (OR 2.727 P<0.001), abdominal surgery (OR 2.575, P<0.001) and disease severity according to the Gigot classification (Type 3 OR 2.853, P<0.001) were identified as risk factors. Height-adjusted total liver volume was an independent polycystic liver disease specific risk factor in the subgroup of patients with known total liver volume (OR 1.363, P=0.001). Patients with multiple hernias were older (62.1 vs 55.1, P=0.001) and more frequently male (22.0 vs 50.0%, P=0.001).
    CONCLUSION: Abdominal wall hernias occur frequently in polycystic liver disease with a predominance of umbilical hernias. Hepatomegaly is a clear disease-specific risk factor.
    Keywords:  abdominal wall hernia; hepatomegaly; polycystic liver disease
    DOI:  https://doi.org/10.1111/liv.15177
  20. J Vis Exp. 2022 Jan 19.
      Primary ciliary dyskinesia (PCD) is a congenital disorder predominantly inherited in an autosomal recessive trait. The disorder causes disturbance in the motion of cilia, leading to severe impairment of mucociliary clearance (MCC). If undiagnosed or diagnosed too late, the condition leads to the development of bronchiectasis and serious damage to the lungs in later life. Most of the methods for diagnosing PCD are time-consuming and demand extensive economic resources to establish them. High-speed video microscopy analysis (HSVMA) is the only diagnostic tool to visualize and analyze living respiratory cells with beating cilia in vitro. It is fast, cost-effective, and, in experienced hands, very reliable as a diagnostic tool for PCD. In addition, classical diagnostic measures such as transmission electron microscopy (TEM) are not applicable for some mutations as morphological changes are absent. This paper describes the process of collecting respiratory epithelial cells, the further preparation of the specimen, and the process of HSVMA. We also describe how brushed cells can be successfully kept unharmed and beating by keeping them in a nourishing medium for storage and transport to the investigation site in cases where a clinic does not possess the equipment to perform HSVMA. Also shown are videos with pathologic beating patterns from patients with a mutation in the dynein arm heavy chain 11 gene (DNAH11), which cannot be diagnosed with TEM; the result of an inconclusive HSVMA due to infection of the upper airways, as well as an unsuccessful brushing with superimposition of red blood cells. With this article, we would like to encourage every unit dealing with pulmonology patients and rare lung diseases to perform HSVMA as part of their daily routine diagnostics for PCD or send the specimens over to a center specializing in performing HSVMA.
    DOI:  https://doi.org/10.3791/63292
  21. Oxid Med Cell Longev. 2022 ;2022 7502632
       Aim: The study is aimed at verifying miR-154-5p and Smurf1 combination in glomerular mesangial cells regulating TGFβ1/Smad3 pathway-related protein ubiquitination in the model of diabetic rats renal tissues, primary mesangial cells, and cell lines.
    Methods: The diabetic SD rat model and high-glucose-cultured primary mesangial cells and cell lines were established. miR-154-5p mimic and inhibitor, Smurf1 siRNA, and TGF β 1/Smad3 inhibitor (SB431542) were pretreated to make the TGFβ1/Smad3 pathway and ubiquitin changes. Fluorescence in situ hybridization was used for the miR-154-5p renal localization; molecular biological detection was adopted for cell proliferation, renal function, urine protein, and pathway proteins. After bioinformatics predicted binding sites, luciferase and Co-IP were used to detect miRNA and protein binding.
    Results: miR-154-5p was significantly increased and mainly concentrated in the glomerular of renal cortex in well-established diabetic rat renal tissues. Rno-miR-154-5p combined Rno-Smurf1 3' UTR, while Smurf1 combined Smad3 directly. Meanwhile, miR-154-5p regulates TGFβ1/Smad3-mediated cell proliferation via Smurf1 ubiquitination.
    Conclusion: miR-154-5p regulates the TGFβ1/Smads pathway through Smurf1 ubiquitination and promotes the fibrosis process of diabetic kidney disease.
    DOI:  https://doi.org/10.1155/2022/7502632