bims-bicyki 2022-07-24 papers

bims-bicyki

Biomed News

on Bicaudal-C1 and interactors in cystic kidney disease

Issue of 2022–07–24
eightteen papers selected by
Céline Gagnieux, École Polytechnique Fédérale de Lausanne

Anoctamin 1 Inhibition Suppresses Cystogenesis by Enhancing Ciliogenesis and the Ciliary Dosage of Polycystins.
Chromatin Methylation Abnormalities in Autosomal Dominant Polycystic Kidney Disease.
Restoration of atypical protein kinase C ζ function in autosomal dominant polycystic kidney disease ameliorates disease progression.
Drugs in Clinical Development to Treat Autosomal Dominant Polycystic Kidney Disease.
Small hairpin inhibitory RNA delivery in the metanephric organ culture identifies long noncoding RNA Pvt1 as a modulator of cyst growth.
Molecular Mechanisms of Epigenetic Regulation, Inflammation, and Cell Death in ADPKD.
Kynurenines in polycystic kidney disease.
Alteration of primary cilia morphology and associated signalling in ameloblastoma.
[Low-frequency pulsed electromagnetic fields promote osteoblast mineralization and maturation of rats through the PC2/sAC/PKA/CREB signaling pathway].
Temperature effects on the disappearance and reappearance of corneal-endothelium primary cilia.
A local interplay between diffusion and intraflagellar transport distributes TRPV-channel OCR-2 along C. elegans chemosensory cilia.
Measurement of ciliary beating and fluid flow in the zebrafish adult telencephalon.
Shenqihuatan formula reduces inflammation by inhibiting transforming growth factor-beta-stimulated signaling pathway in airway smooth muscle cells.
Insights Gained From Zebrafish Models for the Ciliopathy Joubert Syndrome.
A biallelic loss-of-function PDIA6 variant in a second patient with polycystic kidney disease, infancy-onset diabetes, and microcephaly.
The ciliopathy protein CCDC66 controls mitotic progression and cytokinesis by promoting microtubule nucleation and organization.
Clinical and genetic spectrum of primary ciliary dyskinesia in Chinese patients: a systematic review.
Sirt6 deficiency contributes to mitochondrial fission and oxidative damage in podocytes via ROCK1-Drp1 signalling pathway.

Front Biosci (Landmark Ed). 2022 Jul 08. 27(7): 216

Anoctamin 1 Inhibition Suppresses Cystogenesis by Enhancing Ciliogenesis and the Ciliary Dosage of Polycystins.

Tao Xu, Meihan Chen, Qingwen Xu, Cheng Xue, Lili Fu, Kun Ling, Jinghua Hu, Changlin Mei.

   BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is a ciliopathy characterized by abnormal tubular epithelial proliferation and fluid secretion. Anoctamin 1 (ANO1) is a calcium-dependent chloride channel. However, how ANO1 contributes to ADPKD is largely unexplored.
METHODS: Kidney tissues from ADPKD patients, Pkd1RC/RC mice model, WT9-7 human PKD1+⁣/- cells, and 3D culture models in vitro were used. Localization of ANO1 and cilium length were investigated by confocal immunofluorescence.
RESULTS: We found that ANO1 was consistently upregulated in human and mouse PKD kidneys. Intriguingly, ANO1 located in a vesicle-like pattern at the ciliary base but not on the ciliary surface. ANO1 deficiency enhanced ciliogenesis and the ciliary dosage of polycystin-2 in human PKD cells, and reduced cyst formation in 3D culture models. Moreover, inhibition of ANO1 abolished the activation of STAT3 and ERK pathways in PKD cells.
CONCLUSIONS: Our data indicate ANO1 is a negative regulator for both cilia length and cilia trafficking of polycystin-2 and provide mechanistic insights regarding the therapeutic potential of ANO1 pathway in ADPKD treatment.

Keywords:  anoctamin 1; autosomal dominant polycystic kidney disease; polycystin; primary cilium

DOI:  https://doi.org/10.31083/j.fbl2707216
Front Med (Lausanne). 2022 ;9 921631

Chromatin Methylation Abnormalities in Autosomal Dominant Polycystic Kidney Disease.

Jing Xu, Cheng Xue, Xiaodong Wang, Lei Zhang, Changlin Mei, Zhiguo Mao.

  Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease worldwide and is one of the major causes of end-stage renal disease. PKD1 and PKD2 are two genes that mainly contribute to the development and progression of ADPKD. The precise mechanism is not fully understood. In recent years, epigenetic modification has drawn increasing attention. Chromatin methylation is a very important category of PKD epigenetic changes and mostly involves DNA, histone, and RNA methylation. Genome hypomethylation and regional gene hypermethylation coexist in ADPKD. We found that the genomic DNA of ADPKD kidney tissues showed extensive demethylation by whole-genome bisulphite sequencing, while some regional DNA methylation from body fluids, such as blood and urine, can be used as diagnostic or prognostic biomarkers to predict PKD progression. Histone modifications construct the histone code mediated by histone methyltransferases and contribute to aberrant methylation changes in PKD. Considering the complexity of methylation abnormalities occurring in different regions and genes on the PKD epigenome, more specific therapy aiming to restore to the normal genome should lead to the development of epigenetic treatment.

Keywords:  DNA methylation; RNA methylation; autosomal dominant polycystic kidney disease; epigenetics; histone methylation

DOI:  https://doi.org/10.3389/fmed.2022.921631
Proc Natl Acad Sci U S A. 2022 Jul 26. 119(30): e2121267119

Restoration of atypical protein kinase C ζ function in autosomal dominant polycystic kidney disease ameliorates disease progression.

Masaw Akbari, Jonathan D West, Nicholas Doerr, Kevin R Kipp, Neda Marhamati, Sabrina Vuong, Yidi Wang, Markus M Rinschen, Jeffrey J Talbot, Oliver Wessely, Thomas Weimbs.

  Autosomal dominant polycystic kidney disease (ADPKD) affects more than 500,000 individuals in the United States alone. In most cases, ADPKD is caused by a loss-of-function mutation in the PKD1 gene, which encodes polycystin-1 (PC1). Previous studies reported that PC1 interacts with atypical protein kinase C (aPKC). Here we show that PC1 binds to the ζ isoform of aPKC (PKCζ) and identify two PKCζ phosphorylation sites on PC1's C-terminal tail. PKCζ expression is down-regulated in patients with ADPKD and orthologous and nonorthologous PKD mouse models. We find that the US Food and Drug Administration-approved drug FTY720 restores PKCζ expression in in vitro and in vivo models of polycystic kidney disease (PKD) and this correlates with ameliorated disease progression in multiple PKD mouse models. Importantly, we show that FTY720 treatment is less effective in PKCζ null versions of these PKD mouse models, elucidating a PKCζ-specific mechanism of action that includes inhibiting STAT3 activity and cyst-lining cell proliferation. Taken together, our results reveal that PKCζ down-regulation is a hallmark of PKD and that its stabilization by FTY720 may represent a therapeutic approach to the treat the disease.

Keywords:  polycystic kidney disease; polycystin-1; protein kinase C ζ

DOI:  https://doi.org/10.1073/pnas.2121267119
Drugs. 2022 Jul 19.

Drugs in Clinical Development to Treat Autosomal Dominant Polycystic Kidney Disease.

Thomas Bais, Ron T Gansevoort, Esther Meijer.

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by progressive cyst formation that ultimately leads to kidney failure in most patients. Approximately 10% of patients who receive kidney replacement therapy suffer from ADPKD. To date, a vasopressin V2 receptor antagonist (V2RA) is the only drug that has been proven to attenuate disease progression. However, aquaresis-related adverse events limit its widespread use. Data on the renoprotective effects of somatostatin analogues differ largely between studies and medications. This review discusses new drugs that are investigated in clinical trials to treat ADPKD, such as cystic fibrosis transmembrane conductance regulator (CFTR) modulators and micro RNA inhibitors, and drugs already marketed for other indications that are being investigated for off-label use in ADPKD, such as metformin. In addition, potential methods to improve the tolerability of V2RAs are discussed, as well as methods to select patients with (likely) rapid disease progression and issues regarding the translation of preclinical data into clinical practice. Since ADPKD is a complex disease with a high degree of interindividual heterogeneity, and the mechanisms involved in cyst growth also have important functions in various physiological processes, it may prove difficult to develop drugs that target cyst growth without causing major adverse events. This is especially important since long-standing treatment is necessary in this chronic disease. This review therefore also discusses approaches to targeted therapy to minimize systemic side effects. Hopefully, these developments will advance the treatment of ADPKD.

DOI: https://doi.org/10.1007/s40265-022-01745-9
Am J Physiol Renal Physiol. 2022 Jul 21.

Small hairpin inhibitory RNA delivery in the metanephric organ culture identifies long noncoding RNA Pvt1 as a modulator of cyst growth.

Kara Eckberg, Ivan Weisser, Daniel Buttram, Nikunj Somia, Peter Igarashi, Karam S Aboudehen.

  Autosomal dominant polycystic kidney disease (ADPKD) is a monogenic disorder characterized by the formation of kidney cysts that originate from the epithelial tubules of the nephron and primarily results from mutations in PKD1 and PKD2. The metanephric organ culture (MOC) is an ex vivo system in which explanted embryonic kidneys undergo tubular differentiation and kidney development. The MOC has been previously used to study PKD since treatment with 8-Br-cAMP induces the formation of kidney cysts. However, the inefficiency of manipulating gene expression in MOC has limited its utility for identifying genes and pathways that are involved in cystogenesis. Here, we used a lentivirus and three serotypes of self-complementary adeno-associated viral (scAAV) plasmids that express GFP and found that scAAV serotype D/J transduces the epithelial compartment of MOC at an efficiency of 68%. We utilized scAAV/DJ to deliver small hairpin RNA (shRNA) to knockdown Pvt1, a long noncoding RNA (lncRNA), which was upregulated in kidneys from Pkd1 and Pkd2 mutant mice and humans with ADPKD. shRNA delivery by scAAV/DJ downregulated the expression of Pvt1 by 45% and reduced the cyst index by 53% in wild-type and 32% in Pkd1-null MOCs. Knockdown of Pvt1 decreased the level of c-MYC protein by 60% without affecting Myc mRNA, indicating that Pvt1 regulation of c-MYC was post-transcriptional. These results identify Pvt1 as a lncRNA that modulates cyst progression in the MOC.

Keywords:  Metanephric organ culture; Polycystic kidney disease; Pvt1; Self-complementary adeno-associated virus; c-MYC

DOI:  https://doi.org/10.1152/ajprenal.00016.2022
Front Mol Biosci. 2022 ;9 922428

Molecular Mechanisms of Epigenetic Regulation, Inflammation, and Cell Death in ADPKD.

Ewud Agborbesong, Linda Xiaoyan Li, Lu Li, Xiaogang Li.

  Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disorder, which is caused by mutations in the PKD1 and PKD2 genes, characterizing by progressive growth of multiple cysts in the kidneys, eventually leading to end-stage kidney disease (ESKD) and requiring renal replacement therapy. In addition, studies indicate that disease progression is as a result of a combination of factors. Understanding the molecular mechanisms, therefore, should facilitate the development of precise therapeutic strategies for ADPKD treatment. The roles of epigenetic modulation, interstitial inflammation, and regulated cell death have recently become the focuses in ADPKD. Different epigenetic regulators, and the presence of inflammatory markers detectable even before cyst growth, have been linked to cyst progression. Moreover, the infiltration of inflammatory cells, such as macrophages and T cells, have been associated with cyst growth and deteriorating renal function in humans and PKD animal models. There is evidence supporting a direct role of the PKD gene mutations to the regulation of epigenetic mechanisms and inflammatory response in ADPKD. In addition, the role of regulated cell death, including apoptosis, autophagy and ferroptosis, have been investigated in ADPKD. However, there is no consensus whether cell death promotes or delays cyst growth in ADPKD. It is therefore necessary to develop an interactive picture between PKD gene mutations, the epigenome, inflammation, and cell death to understand why inherited PKD gene mutations in patients may result in the dysregulation of these processes that increase the progression of renal cyst formation.

Keywords:  ADPKD; cell death; epigenetics; inflammation; post-translational modifications

DOI:  https://doi.org/10.3389/fmolb.2022.922428
J Nephrol. 2022 Jul 22.

Kynurenines in polycystic kidney disease.

Jost Klawitter, Matthew J Jackson, Peter H Smith, Katharina Hopp, Michel Chonchol, Berenice Y Gitomer, Melissa A Cadnapaphornchai, Uwe Christians, Jelena Klawitter.

   BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is a common hereditary disorder, characterized by kidney cyst formation. A major pathological feature of ADPKD is the development of interstitial inflammation. Due to its role in inflammation and oxidative stress, tryptophan metabolism and related kynurenines may have relevance in ADPKD.
METHODS: Data were collected from a well-characterized longitudinal cohort of pediatric and adult patients with ADPKD and compared to age-matched healthy subjects. To evaluate the role of kynurenines in ADPKD severity and progression, we investigated their association with height-corrected total kidney volume (HtTKV) and kidney function (estimated glomerular filtration rate (eGFR)). Key tryptophan metabolites were measured in plasma using a validated liquid chromatography-mass spectrometry assay.
RESULTS: There was a significant accumulation of kynurenine and kynurenic acid (KYNA) in children and adults with ADPKD as compared to healthy subjects. Downstream kynurenines continued to accumulate in adults with ADPKD concurrent with the increase of inflammatory markers IL-6 and MCP-1. Both markers remained unchanged in ADPKD as compared to healthy children, suggesting alternate pathways responsible for the observed rise in kynurenine and KYNA. KYNA and kynurenine/tryptophan positively associated with disease severity (HtTKV or eGFR) in patients with ADPKD. After Bonferroni adjustment, baseline kynurenines did not associate with disease progression (yearly %change in HtTKV or yearly change in eGFR) in this limited number of patients with ADPKD.
CONCLUSION: Kynurenine metabolism seems dysregulated in ADPKD as compared to healthy subjects. Inhibition of kynurenine production by inhibition of main pathway enzymes could present a novel way to reduce the progression of ADPKD.

Keywords:  ADPKD; Kynurenines; Tryptophan

DOI:  https://doi.org/10.1007/s40620-022-01361-6
Arch Oral Biol. 2022 Jul 04. pii: S0003-9969(22)00156-X. [Epub ahead of print]142 105499

Alteration of primary cilia morphology and associated signalling in ameloblastoma.

Jana Filušová, Iveta Putnová, Pavel Hurník, Zdeněk Daněk, Ctirad Macháček, Jan Štembírek, Marcela Buchtová, Barbora Moldovan Putnová.

   OBJECTIVES: Primary cilium is a cellular organelle with growing significance confirmed in tumour biology. Primary cilia have been associated with fine tuning of numerous cell signalling pathways and the role of this structure in cancer initiation and progression is recently at the forefront of attention. Here, we investigated possible alterations in the occurrence of primary cilia and changes of associated signalling in ameloblastoma, which represents the most common odontogenic tumour.
METHODS: We performed immunohistochemistry to assess the number and morphology of primary cilia in ameloblastoma tissues. The gene expression of key SHH pathway members was analysed by qPCR. As a functional experiment, we treated a primary ameloblastoma cell line by a SHH pathway inhibitor Sonidegib (LDE225).
RESULTS: We uncovered differences in primary cilia distribution and appearance in histological subtypes of ameloblastoma with the highest number of ciliated cells in plexiform and follicular subtypes. SHH protein was located close to primary cilia in ameloblastoma epithelial cells and the expression of molecules downstream of SHH signalling was upregulated. Moreover, the inhibition of SHH pathway by Sonidegib caused downregulation of SHH effector gene GLI1 and cell cycle regulator CCND1 in ameloblastoma primary cell line. The inhibition of SHH signalling also altered the expression of molecules involved in intraflagellar transport.
CONCLUSIONS: In conclusion, our study uncovered alterations in number of ciliated cells and associated signalling in ameloblastoma, which indicate SHH inhibitors as potential therapeutic target to treat this disease.

Keywords:  Ameloblastoma; IFT; Primary cilia; SHH

DOI:  https://doi.org/10.1016/j.archoralbio.2022.105499
Nan Fang Yi Ke Da Xue Xue Bao. 2022 Jul 20. 42(7): 988-996

[Low-frequency pulsed electromagnetic fields promote osteoblast mineralization and maturation of rats through the PC2/sAC/PKA/CREB signaling pathway].

Y He, K Chen, P Wei, G Xie, Z Chen, K Qin, Y Gao, H Ma.

   OBJECTIVE: To explore whether the effect of low-frequency pulsed electromagnetic fields (PEMFs) in promoting osteoblast mineralization and maturation is related to the primary cilia, polycystin2 (PC2) and sAC/PKA/CREB signaling pathway.
METHODS: We detected the expression levels of PC2, sAC, PKA, CREB and their phosphorylated proteins in primary rat calvarial osteoblasts exposed to 50 Hz 0.6 mT PEMFs for 0, 5, 15, 30, 60, 90, and 120 min. We blocked PC2 function with amiloride hydrochloride and detected the changes in the activity of sAC/PKA/CREB signal pathway and the mineralization and maturation of the osteoblasts. These examinations were repeated in the osteoblasts after specific knockdown of PC2 via RNA interference and were the co-localization of PC2, sAC, PKA, CREB and their phosphorylated proteins with the primary cilia were using immunofluorescence staining. The expressions of PC2 and the signaling proteins of sAC/PKA/CREB pathway were detected after inhibition of primary ciliation by RNA interference.
RESULTS: The expression levels of PC2, sAC, p-PKA and p- CREB were significantly increased in the osteoblasts after exposure to PEMFs for different time lengths (P < 0.01). Blocking PC2 function or PC2 knockdown in the osteoblasts resulted in failure of sAC/PKA/CREB signaling pathway activation and arrest of osteoblast mineralization and maturation. PC2, sAC, p-PKA and p-CREB were localized to the entire primary cilia or its roots, but PKA and CREB were not detected in the primary cilia. After interference of the primary cilia, PEMFs exposure no longer caused increase of PC2 expression and failed to activate the sAC/PKA/CREB signaling pathway or promote osteoblast mineralization and maturation.
CONCLUSION: PC2, located on the surface of the primary cilia of osteoblasts, can perceive and transmit the physical signals from PEMFs and promote the mineralization and maturation of osteoblasts by activating the PC2/ sAC/PKA/CREB signaling pathway.

Keywords:  low-frequency pulsed electromagnetic field; osteoblasts; polycystin2; sAC/PKA/CREB signaling pathway

DOI:  https://doi.org/10.12122/j.issn.1673-4254.2022.07.04
Jpn J Ophthalmol. 2022 Jul 21.

Temperature effects on the disappearance and reappearance of corneal-endothelium primary cilia.

Hidetoshi Tanioka, Katsuhiko Shinomiya, Shigeru Kinoshita, Chie Sotozono.

   INTRODUCTION: To elucidate the specific functions of the primary cilia in corneal endothelial cells (CECs) by investigating the histological changes of corneal endothelium exposed at low temperature.
STUDY DESIGN: Experimental study.
METHODS: This study involved corneas freshly obtained from Japanese white rabbits preserved in Optisol™-GS (Bausch & Lomb) corneal storage medium at 4 °C for 0, 1, and 7 days. Corneas preserved for 7 days were also incubated at 37 °C in culture media for an additional 2 days. A rabbit CEC line was also preserved in Optisol™-GS at 4 °C for 0 and 1 day. The corneal endothelium specimens and CECs were then assessed by immunostaining and scanning electron-microscopy (SEM).
RESULTS: Immediately post isolation, the CECs of the specimens showed positive immunostaining for primary cilia (i.e., approximately 20%) via anti-acetylated alpha Tubulin antibody and SEM observation. Primary cilia were found to have attenuated/disappeared on the corneal endothelium specimens preserved for 1 or 7 days at 4 °C. After an additional 2-day incubation at 37 °C, primary cilia reappeared on the corneal endothelium specimens (approximately 20%). The disappearance of cilia during the preservation period was also observed in the immortalized CECs.
CONCLUSION: The findings in this study using rabbit corneas indicate that the primary cilia of corneal endothelium preserved at low temperature disappeared, then reappeared after returning to body temperature, suggesting that temperature has a direct effect on the primary cilia of corneal endothelium.

Keywords:  Corneal endothelium; Preservation; Primary cilia; Rabbits; Temperature

DOI:  https://doi.org/10.1007/s10384-022-00933-0
Commun Biol. 2022 Jul 20. 5(1): 720

A local interplay between diffusion and intraflagellar transport distributes TRPV-channel OCR-2 along C. elegans chemosensory cilia.

Jaap van Krugten, Noémie Danné, Erwin J G Peterman.

To survive, Caenorhabditis elegans depends on sensing soluble chemicals with transmembrane proteins (TPs) in the cilia of its chemosensory neurons. Cilia rely on intraflagellar transport (IFT) to facilitate the distribution of cargo, such as TPs, along the ciliary axoneme. Here, we use fluorescence imaging of living worms and perform single-molecule tracking experiments to elucidate the dynamics underlying the ciliary distribution of the sensory TP OCR-2. Quantitative analysis reveals that the ciliary distribution of OCR-2 depends on an intricate interplay between transport modes that depends on the specific location in the cilium: in dendrite and transition zone, directed transport is predominant. Along the cilium motion is mostly due to normal diffusion together with a small fraction of directed transport, while at the ciliary tip subdiffusion dominates. These insights in the role of IFT and diffusion in ciliary dynamics contribute to a deeper understanding of ciliary signal transduction and chemosensing.

DOI: https://doi.org/10.1038/s42003-022-03683-4
STAR Protoc. 2022 Jul 15. pii: S2666-1667(22)00422-1. [Epub ahead of print]3(3): 101542

Measurement of ciliary beating and fluid flow in the zebrafish adult telencephalon.

Inyoung Jeong, Jan Niklas Hansen, Dagmar Wachten, Nathalie Jurisch-Yaksi.

  Motile cilia are hair-like structures that move and propel fluid, playing important roles in the physiology of organs. Here, we present a protocol to visualize and measure ciliary beating and cerebrospinal fluid (CSF) flow in the telencephalon of an adult zebrafish brain explant. We describe the preparation of brain explants, the recording of ciliary beating and CSF flow, and data analysis using ImageJ and MATLAB. These imaging and analysis techniques can be directly translated to other ciliated systems. For complete details on the use and execution of this protocol, please refer to D'Gama et al. (2021).

Keywords:  Cell Biology; Microscopy; Model Organisms; Neuroscience

DOI:  https://doi.org/10.1016/j.xpro.2022.101542
J Tradit Chin Med. 2022 Aug;42(4): 520-529

Shenqihuatan formula reduces inflammation by inhibiting transforming growth factor-beta-stimulated signaling pathway in airway smooth muscle cells.

Chen Jingjing, Wang Yuanyuan, Zhang Nianzhi, Xue Xiaoming.

   OBJECTIVE: To study the effects and mechanism of Shenqihuatan formula (, SQHT) of the transforming growth factor-beta (TGF-β)-stimulated cell processes in airway remodeling.
METHODS: The current study examined cell viability using a Cell Counting Kit-8 assay. Furthermore, a Transwell assay was conducted to detect the ability of cell migration, and apoptosis was detected via flowcytometry. Western Blot and quantitative real-time polymerase chain reaction (qRT-PCR) were used to determine the expression levels of apoptosis or inflammation-related factors, such as TGF-β, Interleukin-1β (IL-1β), B cell lymphoma 2 (Bcl-2), Bcl-2-Associated X (Bax), Ras homolog gene family, member A (RhoA), recombinant rho associated coiled coil containing protein kinase 1/2 (ROCK1/2), extracellular regulated protein kinases 1/2 (ERK1/2), Snail, and Slug. Finally, the expression levels of matrix metalloproteinase-9 (MMP-9) and Tissue inhibitor of metalloproteinase (TIMP-1) were admeasured by enzyme-linked immuno sorbent assay.
RESULTS: The results demonstrated that SQHT inhibited the viability and migration, as well as the the F-actin formation and cytoskeletal reorganization of airway smooth muscle cells (ASMCs) stimulated by TGF-β. By monitoring the changes of critical regulators in the presence of the formula, it was observed that the expression levels of TGF-β, IL-1β, Bcl-2, RhoA, ROCK1/2, ERK1/2, Snail, and Slug were markedly suppressed, whereas Bax expression exhibited the opposite effect. Compared with a well-characterized RhoA pathway inhibitor, Fasudil, SQHT generated equivalent or even higher inhibitory effects on these processes in ASMCs.
CONCLUSIONS: Collectively, these suggested that SQHT can reduce airway inflammation by inhibiting TGF-β-stimulated signaling pathways in ASMCs. These findings may provide a novel remedy for treating ASMC inflammation, which causes thickening and obstruction of the airway in chronic obstructive pulmonary disease.

Keywords:  Shenqihuatan formula; airway inflammation; fasudil; pulmonary disease, chronic obstructive; transforming growth factor beta

DOI:  https://doi.org/10.19852/j.cnki.jtcm.20220519.001
Front Genet. 2022 ;13 939527

Insights Gained From Zebrafish Models for the Ciliopathy Joubert Syndrome.

Tamara D S Rusterholz, Claudia Hofmann, Ruxandra Bachmann-Gagescu.

  Cilia are quasi-ubiquitous microtubule-based sensory organelles, which play vital roles in signal transduction during development and cell homeostasis. Dysfunction of cilia leads to a group of Mendelian disorders called ciliopathies, divided into different diagnoses according to clinical phenotype constellation and genetic causes. Joubert syndrome (JBTS) is a prototypical ciliopathy defined by a diagnostic cerebellar and brain stem malformation termed the "Molar Tooth Sign" (MTS), in addition to which patients display variable combinations of typical ciliopathy phenotypes such as retinal dystrophy, fibrocystic renal disease, polydactyly or skeletal dystrophy. Like most ciliopathies, JBTS is genetically highly heterogeneous with ∼40 associated genes. Zebrafish are widely used to model ciliopathies given the high conservation of ciliary genes and the variety of specialized cilia types similar to humans. In this review, we compare different existing JBTS zebrafish models with each other and describe their contributions to our understanding of JBTS pathomechanism. We find that retinal dystrophy, which is the most investigated ciliopathy phenotype in zebrafish ciliopathy models, is caused by distinct mechanisms according to the affected gene. Beyond this, differences in phenotypes in other organs observed between different JBTS-mutant models suggest tissue-specific roles for proteins implicated in JBTS. Unfortunately, the lack of systematic assessment of ciliopathy phenotypes in the mutants described in the literature currently limits the conclusions that can be drawn from these comparisons. In the future, the numerous existing JBTS zebrafish models represent a valuable resource that can be leveraged in order to gain further insights into ciliary function, pathomechanisms underlying ciliopathy phenotypes and to develop treatment strategies using small molecules.

Keywords:  CRISPR/Cas9; Joubert syndrome; cilia; ciliopathies; morpholino (MO); retina; zebrafish

DOI:  https://doi.org/10.3389/fgene.2022.939527
Clin Genet. 2022 Jul 18.

A biallelic loss-of-function PDIA6 variant in a second patient with polycystic kidney disease, infancy-onset diabetes, and microcephaly.

Elisa De Franco, Matthew N Wakeling, Russel D Frew, James Russ-Silsby, Catherine Peters, Stephen D Marks, Andrew T Hattersley, Sarah E Flanagan.

  We report a second patient with intrauterine growth retardation, congenital polycystic kidney disease, infancy-onset diabetes, microcephaly, and liver fibrosis caused by a homozygous PDIA6 loss-of-function variant. Our study further defines the genetic and clinical features of this rare syndromic form of infancy-onset diabetes.

Keywords:  PDIA6; infancy-onset diabetes; microcephaly; polycystic kidney disease; transcript; whole genome sequencing

DOI:  https://doi.org/10.1111/cge.14187
PLoS Biol. 2022 Jul 18. 20(7): e3001708

The ciliopathy protein CCDC66 controls mitotic progression and cytokinesis by promoting microtubule nucleation and organization.

Umut Batman, Jovana Deretic, Elif Nur Firat-Karalar.

Precise spatiotemporal control of microtubule nucleation and organization is critical for faithful segregation of cytoplasmic and genetic material during cell division and signaling via the primary cilium in quiescent cells. Microtubule-associated proteins (MAPs) govern assembly, maintenance, and remodeling of diverse microtubule arrays. While a set of conserved MAPs are only active during cell division, an emerging group of MAPs acts as dual regulators in dividing and nondividing cells. Here, we elucidated the nonciliary functions and molecular mechanism of action of the ciliopathy-linked protein CCDC66, which we previously characterized as a regulator of ciliogenesis in quiescent cells. We showed that CCDC66 dynamically localizes to the centrosomes, the bipolar spindle, the spindle midzone, the central spindle, and the midbody in dividing cells and interacts with the core machinery of centrosome maturation and MAPs involved in cell division. Loss-of-function experiments revealed its functions during mitotic progression and cytokinesis. Specifically, CCDC66 depletion resulted in defective spindle assembly and orientation, kinetochore fiber stability, chromosome alignment in metaphase as well as central spindle and midbody assembly and organization in anaphase and cytokinesis. Notably, CCDC66 regulates mitotic microtubule nucleation via noncentrosomal and centrosomal pathways via recruitment of gamma-tubulin to the centrosomes and the spindle. Additionally, CCDC66 bundles microtubules in vitro and in cells by its C-terminal microtubule-binding domain. Phenotypic rescue experiments showed that the microtubule and centrosome-associated pools of CCDC66 individually or cooperatively mediate its mitotic and cytokinetic functions. Collectively, our findings identify CCDC66 as a multifaceted regulator of the nucleation and organization of the diverse mitotic and cytokinetic microtubule arrays and provide new insight into nonciliary defects that underlie ciliopathies.

DOI: https://doi.org/10.1371/journal.pbio.3001708
Orphanet J Rare Dis. 2022 Jul 19. 17(1): 283

Clinical and genetic spectrum of primary ciliary dyskinesia in Chinese patients: a systematic review.

Bo Peng, Yong-Hua Gao, Jia-Qi Xie, Xiao-Wen He, Cong-Cong Wang, Jin-Fu Xu, Guo-Jun Zhang.

   BACKGROUND: Primary ciliary dyskinesia (PCD) represents a highly heterogenous disorder with extensive clinical and genetic patterns among populations of different geographic location and ethnic origin. However, data about Chinese patients are limited. We aimed to summarize the clinical and genetic spectrum of Chinese PCD patients based on all available literatures.
METHODS: We searched Embase, Pubmed, Web of Science and Chinese databases including CNKI, SinoMed and Wanfang from 1981 to 2021, to identify articles reporting patients with PCD in China, which had included information about transmission electron microscopy and/or genetic testing.
RESULTS: A total of 244 Chinese PCD patients in 52 articles were included. Of these patients, the mean age was 13.1 years, and 55 patients (22.5%) were diagnosed with PCD after 18 years old. Compared with patients diagnosed with PCD in childhood or infancy, patients diagnosed with PCD in adulthood had a higher prevalence of chronic wet cough, sinusitis, Pseudomonas aeruginosa (PA) isolation and radiological bronchiectasis as well as worse lung function. 25 PCD-related genes were identified in 142 patients, and DNAH5, DNAH11, CCDC39 and CCDC40 were the most frequently detected mutations. More than half of genetic variants were loss-of-function mutations, and the majority of these variants were seen only once. Correlations between PCD phenotype, genotype and ciliary ultrastructure were also evidenced.
CONCLUSIONS: Diagnostic delay and under-recognition of PCD remain a big issue in China, which contributes to progressive lung disease and PA infection indicating worse outcome. Specialist equipment and expertise are urgently required to facilitate the early diagnosis and treatment of PCD.
TRIAL REGISTRY: PROSPERO; No.: CRD42021257804; URL: www.crd.york.ac.uk/prospero/.

Keywords:  Cilia; Genotype; PCD; Phenotype; Systematic review

DOI:  https://doi.org/10.1186/s13023-022-02427-1
Cell Prolif. 2022 Jul 17. e13296

Sirt6 deficiency contributes to mitochondrial fission and oxidative damage in podocytes via ROCK1-Drp1 signalling pathway.

Zhaowei Chen, Wei Liang, Jijia Hu, Zijing Zhu, Jun Feng, Yiqiong Ma, Qian Yang, Guohua Ding.

OBJECTIVES: Increasing evidence suggests that mitochondrial dysfunction is the key driver of angiotensin II (Ang II)-induced kidney injury. This study was designed to investigate whether Sirtuin 6 (Sirt6) could affect Ang II-induced mitochondrial damage and the potential mechanisms.
MATERIALS AND METHODS: Podocyte-specific Sirt6 knockout mice were infused with Ang II and cultured podocytes were stimulated with Ang II to evaluate the effects of Sirt6 on mitochondrial structure and function in podocytes. Immunofluorescence staining was used to detect protein expression and mitochondrial morphology in vitro. Electron microscopy was used to assess mitochondrial morphology in mice. Western blotting was used to quantify protein expression.
RESULTS: Mitochondrial fission and decreased Sirt6 expression were observed in podocytes from Ang II-infused mice. In Sirt6-deficient mice, Ang II infusion induced increased apoptosis and mitochondrial fragmentation in podocytes than that in Ang II-infused wild-type mice. In cultured human podocytes, Sirt6 knockdown exacerbated Ang II-induced mitochondrial fission, whereas Sirt6 overexpression ameliorated the Ang II-induced changes in the balance between mitochondrial fusion and fission. Functional studies revealed that Sirt6 deficiency exacerbated mitochondrial fission by promoting dynamin-related protein 1 (Drp1) phosphorylation. Furthermore, Sirt6 mediated Drp1 phosphorylation by promoting Rho-associated coiled coil-containing protein kinase 1 (ROCK1) expression.
CONCLUSION: Our study has identified Sirt6 as a vital factor that protects against Ang II-induced mitochondrial fission and apoptosis in podocytes via the ROCK1-Drp1 signalling pathway.

DOI: https://doi.org/10.1111/cpr.13296