bims-bicyki 2022-05-15 papers

bims-bicyki

Biomed News

on Bicaudal-C1 and interactors in cystic kidney disease

Issue of 2022–05–15
twenty papers selected by
Céline Gagnieux, École Polytechnique Fédérale de Lausanne

Primary cilia control kidney inflammation and scarring in response to obstruction.
Polycystin 1 ciliary localization is regulated by its aGPCR activity.
Pharmacological effect of pinostrobin on CFTR-mediated Cl- secretion and renal cyst development in in vitro model of polycystic kidney disease.
Antiphospholipid Syndrome in a Patient With Autosomal Dominant Polycystic Kidney Disease: The Surface of the Moon.
Ambulatory pulse pressure and its contributors in autosomal dominant polycystic kidney disease.
Transcriptomic and metabolic profiling of Tolvaptan treated Autosomal dominant polycystic kidney disease (ADPKD) patient.
Genetics, pathobiology and therapeutic opportunities of polycystic liver disease.
Calcium-dependent signaling via gap junctions drives RhoA/ROCK activation during collective cell migration.
Effects of flow and polycystin-1 dysfunction on ATP release in the inner medullary collecting duct of the kidney.
Afferent Renal Nerve Activity is Proportionately Increased with Cystic Progression in a Preclinical Model of Autosomal Recessive Polycystic Kidney Disease.
The role of primary cilia in pulmonary hypertension.
Cilia-localized GID/CTLH ubiquitin ligase complex regulates protein homeostasis of sonic hedgehog signaling components.
Uncovering the Ciliogenesis Regulatory Network.
Effectiveness of Open Fenestration for Autosomal Dominant Polycystic Liver Disease.
SPECC1L deficiency causes shortened primary cilia and genetically interacts with IFT-A deficiency to affect palatogenesis.
The Cytoskeleton Effectors Rho-Kinase (ROCK) and Mammalian Diaphanous-Related (mDia) Formin Have Dynamic Roles in Tumor Microtube Formation in Invasive Glioblastoma Cells.
Loss of ciliary adenylyl cyclase 3 in the ventromedial hypothalamus resulted in a sex-dependent obese phenotype.
Inhibiting ADAM10-MMP14 Complex Blocks Cystogenesis of Kidney Epithelial Cells.
Role of abnormal energy metabolism in the progression of chronic kidney disease and drug intervention.
Clinical phenotypes of primary ciliary dyskinesia.

FASEB J. 2022 May;36 Suppl 1

Primary cilia control kidney inflammation and scarring in response to obstruction.

Amandine Aka, Amandine Viau, Marceau Quatredeniers, Fabiola Terzi, Frank Bienaimé.

Primary cilium is a unique antenna-like structure that protrudes from the surface of most mammalian cells. Primary cilia are located at the apical surface of renal tubular epithelial cells, where they are bathed in the forming urine. Overall, primary cilia are signaling platforms that integrate mechanical and chemical cues. Yet, the functions of tubular cells cilia in kidney physiology remain unclear. Mutations in genes encoding ciliary proteins frequently lead to the development of chronic kidney diseases such as Autosomal Dominant Polycystic Kidney Disease or Nephronophthisis. A common denominator of these "renal ciliopathies" is the infiltration of the kidney by immune cells and myofibroblasts that prompt renal scarring. In the absence of mutations, such events can notably be triggered by tubular obstruction, which abolished urinary flux and therefore may affect cilia signaling. Yet the contribution of primary cilia in kidney response to obstruction is unknown. Here, we combined comparative analysis of kidney gene expression datasets, models of mechanical tubular obstruction and genetic ablation of primary cilia to explore this question. Our results indicate that the renal cytokine landscape of ciliopathies massively overlaps with the one induced by ureteral obstruction. Applying this latter model to mice with tubule specific cilia ablation, we demonstrated that cilia are instrumental in the induction of most of these cytokines. Subsequently cilia ablation mitigated macrophage and neutrophil recruitment to the kidney and reduced fibrosis burden. All together, these results show that primary cilia evoke a coordinated response to tubular obstruction reminiscent of genetic renal ciliopathies. Elucidating the mechanisms underlying this function of primary cilia may illuminate the pathophysiology of both genetic and non-genetic chronic kidney diseases. AA* and AV* these authors equally contributed to this work.

DOI: https://doi.org/10.1096/fasebj.2022.36.S1.L7855
FASEB J. 2022 May;36 Suppl 1

Polycystin 1 ciliary localization is regulated by its aGPCR activity.

Nikolay Gresko, Michael Caplan.

Autosomal dominant polycystic kidney disease (ADPKD) develops due to loss of function mutations in the PKD1 and PKD2 genes, which encode PC1 and PC2, respectively. PC1 is a 460kD multi-spanning membrane protein that undergoes multiple proteolytic cleavages, at least two of which release C-terminal fragments. Polycystin 1 and Polycystin 2 both prominently localize to the primary cilium where they contribute to cellular mechano-sensation and also form a cation-permeable heterotetrameric channel that may contribute to Ca2+ flux into the cilia. Recent studies demonstrate that PC1 can function as an atypical adhesion GPCR that is activated by Wnt ligands. Wnt ligand binding leads to dissociation of the PC1 extracellular N terminal fragment and allows the PC1 receptor function to be activated by a tethered agonist peptide that resides at the N terminus of the PC1 transmembrane domains. Here we report that Polycystin 1 cilia and cell surface localization is regulated by its activity status. We demonstrate that a constitutively active form of the Polycystin 1 protein is absent from the primary cilia whereas a constitutively inactive version of the PC1 protein that lacks its tethered agonist peptide resides in the primary cilia. Moreover, we show that interruption of the cellular receptor desensitization process by β-arrestin inhibition permits the constitutively active PC1 construct to accumulate in the cilium. We also studied the surface localization of the full length PC1 and found that extended Wnt9b ligand treatment or mechanical stimulation both lead to reduced quantity of the full length PC1 at the cell surface and in the primary cilium, a process that can be disrupted by inhibition of β-arrestin. In vivo, we find that reduction of the luminal flow in renal tubules by ureter obstruction leads to accumulation of the PC1 in the primary cilia of the tubule cells. Taken together, our data suggest that PC1 surface trafficking is regulated by receptor-activating stimuli including ligand binding and mechanical stress and, similar to the regulation of aGPCR receptors, is subject to an activity-dependent receptor desensitization process. Our findings indicate that the aGPCR receptor-like properties of Polycystin 1 offer new insights into this protein's physiological function and the regulation of its trafficking. Understanding these processes may suggest targets for the development of new therapeutic interventions for ADPKD.

DOI: https://doi.org/10.1096/fasebj.2022.36.S1.R4689
FASEB J. 2022 May;36 Suppl 1

Pharmacological effect of pinostrobin on CFTR-mediated Cl- secretion and renal cyst development in in vitro model of polycystic kidney disease.

Kanlayanee Tonum, Sunhapas Soodvilai.

Cystic fibrosis transmembrane conductance regulator (CFTR) plays crucial role in renal cyst expansion via increase in fluid accumulation. Evidence suggests that inhibition of CFTR retard cyst development and enlargement in polycystic kidney disease (PKD). Here we investigated the pharmacological effect of pinostrobin, a bioactive natural flavonoid on CFTR-mediated Cl- secretion and renal cyst expansion in in vitro model; human autosomal dominant polycystic kidney disease (ADPKD) cell line and Type I Mardin Darby Canine Kidney (MDCK) cells. Treatment with pinostrobin (10 and 50 µM) significantly reduces MDCK cyst formation and enlargement in concentration-dependent manner. Pinostrobin reduces the number of renal cyst colonies corresponding with a decrease in cell proliferation and extracellular signal-regulated kinases (ERK) signaling. Additionally, pinostrobin retarded cyst expansion via inhibition on CFTR-mediated chloride secretion. The inhibitory effect of pinostrobin was not due to the decrease in cell viability and activity of Na+ -K+ -ATPase. Our findings define that pinostrobin might be the candidate for further study as the therapeutic agents for PKD treatment.

DOI: https://doi.org/10.1096/fasebj.2022.36.S1.R3636
Cureus. 2022 Apr;14(4): e24014

Antiphospholipid Syndrome in a Patient With Autosomal Dominant Polycystic Kidney Disease: The Surface of the Moon.

John Dayco, Shahzana Shahzad, Hanna Tran, Mohammed Ali, Mahmoud M Musa, Rashid Alhusain, Abdalaziz M Awadelkarim, Navid Mahabadi, Shaheena Raheem, Aris Urbanes.

  Antiphospholipid syndrome (APS) is a rare coagulopathic disorder diagnosed with a combination of clinical/imaging findings with specific antibody titer elevations over a period of 12 weeks. The following case report will discuss the unusual and challenging hospital course of a patient with extensive autosomal dominant polycystic kidney disease (ADPKD) being treated for a multi-drug resistant urinary tract infection (UTI). The patient later developed multiple deep vein thrombosis (DVT) and was found to have antiphospholipid syndrome. Warfarin, the anticoagulant of choice for antiphospholipid syndrome, has a higher likelihood of intracerebral hemorrhage than direct oral anticoagulants. This is particularly challenging since patients with autosomal dominant polycystic kidney disease have a higher propensity to develop intracranial aneurysms (ICA).

Keywords:  auto immune; autosomal-dominant polycystic kidney disease; complicated urinary tract infection; deep vein thrombosis (dvt); fever of unkown

DOI:  https://doi.org/10.7759/cureus.24014
Adv Clin Exp Med. 2022 May 11.

Ambulatory pulse pressure and its contributors in autosomal dominant polycystic kidney disease.

Agata Koska-Ścigała, Magdalena Jankowska, Anna Szyndler, Krzysztof Narkiewicz, Alicja Dębska-Ślizień.

   BACKGROUND: Pulse pressure (PP) is a pulsatile component of blood pressure (BP), strongly correlated with arterial stiffness (AS) and impacting prognosis. Disproportionally increased PP values in individuals with autosomal dominant polycystic kidney disease (ADPKD) should be expected, given the multifactorial cardiovascular involvement in the natural course of this disease.
OBJECTIVES: To investigate ambulatory PP in a group of ADPKD patients, and to examine the impact of age, sex, kidney function, hypertension, circadian rhythm, and antihypertensive drugs (AH) on studied parameters.
MATERIAL AND METHODS: A total of 130 ADPKD patients (median age 41 years, 35% men) who underwent 24-hour BP measurement with portable oscillometer Spacelabs 90217, were included in the study and their recordings were retrospectively analyzed. Demographic data and the medical history including antihypertensive treatment were collected, ADPKD was diagnosed based on the criteria by Pei et al., and estimated glomerular filtration rate (eGFR) was calculated according to the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation.
RESULTS: Pulse pressure in the whole group was 46 (IQR: 42-53) mm Hg and it was significantly higher in men than in women and during the day compared to nighttime. There was a negative correlation of PP with eGFR and a positive correlation with age. Pulse pressure was not different in ADPKD patients with or without a diagnosis of hypertension.
CONCLUSION: Ambulatory PP is not substantially increased in ADPKD patients across different stages of CKD. It follows a regular pattern of being increased with age, male sex, daytime, and decreasing eGFR, but not with the diagnosis of hypertension.

Keywords:  ADPKD; hypertension; pulse pressure

DOI:  https://doi.org/10.17219/acem/149373
FASEB J. 2022 May;36 Suppl 1

Transcriptomic and metabolic profiling of Tolvaptan treated Autosomal dominant polycystic kidney disease (ADPKD) patient.

Hugo Y Lin, Frank Xu, Li-Lun Ho, Li-Ju Huang, Tzongshi Lu.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is the most common and life-threatening genetic kidney disease that characterized by the aberrant renal tubule epithelial cells proliferation leads to the formation of multiple fluid-filled cysts, and most of the ADPKD patient will leads to kidney failure by age of 50. Currently, dialysis or a transplant are the only treatments for end-stage ADPKD patients. Tolvaptan is a is a selective vasopressin V2-receptor antagonist which was used to treat hyponatremia in heart failure but was approved by FDA for ADPKD treatment in 2018. However, there are limitations for ADPKD patients to receive Tolvaptan treatment and significant side effects severely affect patient's life quality. In our study, a 34-year-old man was diagnosed with familial ADPKD. He had cysts in kidney (Mayo class 1c) and liver and showed no symptoms other than hypertension. His baseline eGFR was 76.98 ml/min/1.732mg/dL but declined to 57.02 ml/min/1.732mg/dL two years after his first diagnosis, and there was an increase in number and size of the cysts due to the rapidly progressive ADPKD. Tolvaptan was started with the 45-0-15 dose and the patient was well-tolerated. After 60 days of treatment, the renal function dramatic improved (73.02 ml/min/1.732mg/dL). With the titrate to 60-0-30 dose of tolvaptan, his eGFR maintains above than 60 ml/min/1.732mg/dL more than 3 months until present.
METHOD: Information of transcriptome and metabolome has significantly contributed to identifying potential therapeutic targets for the management of diseases. In our study, we collect his blood and urine before Tolvaptan treatment and 2 and 3 months after Tolvaptan treatment for transcriptomic and metabolic profiling. Total RNA was extracted using Trizol® Reagent (Invitrogen, USA) according to the manual. cDNA libraries were prepared by SureSelect XT HS2 mRNA Library Preparation kit (Agilent, USA) and sequenced on Nextseq. Differential expression analysis was performed using StringTie and DEseq2 with genome bias detection/correction using Welgene Biotech's in-house pipeline. Genes with p value < 0.05 and > 2.0-fold changes were considered significantly differentially expressed, and functional enrichment assay in differentially expressed genes of each experiment design was performed using clusterProfiler v3.6.
RESULTS: Our data indicates that tight junction proteins (Log2 ratio: CRB3, 11.01; CLDN10, 10.09; MAPK10, 7.34), cytoskeleton regulating proteins (Log2 ratio: FGF17, 9.47; MYH14, 7.04) which also genes involved in the regulation of calcium and MAPK signaling and following focal adhesion proteins were significantly (p<0.05) preserved after 3 months Tolvaptan treatment. Furthermore, Hypoxanthine, Creatine, L-a-aminobutyric acid and Trimethylamine N-oxide were significantly decreased in our metabolomics data analysis which is also indicates the inhibition of paracellular transportation in kidney epithelial/endothelial cells.
CONCLUSION: Our data indicates a potential molecular mechanism of Tolvaptan treatment in regulating the integrity of tight junction and kidney cells, and provides novel therapeutic targets in in ADPKD.

DOI: https://doi.org/10.1096/fasebj.2022.36.S1.R4101
Nat Rev Gastroenterol Hepatol. 2022 May 13.

Genetics, pathobiology and therapeutic opportunities of polycystic liver disease.

Paula Olaizola, Pedro M Rodrigues, Francisco J Caballero-Camino, Laura Izquierdo-Sanchez, Patricia Aspichueta, Luis Bujanda, Nicholas F Larusso, Joost P H Drenth, Maria J Perugorria, Jesus M Banales.

Polycystic liver diseases (PLDs) are inherited genetic disorders characterized by progressive development of intrahepatic, fluid-filled biliary cysts (more than ten), which constitute the main cause of morbidity and markedly affect the quality of life. Liver cysts arise in patients with autosomal dominant PLD (ADPLD) or in co-occurrence with renal cysts in patients with autosomal dominant or autosomal recessive polycystic kidney disease (ADPKD and ARPKD, respectively). Hepatic cystogenesis is a heterogeneous process, with several risk factors increasing the odds of developing larger cysts. Depending on the causative gene, PLDs can arise exclusively in the liver or in parallel with renal cysts. Current therapeutic strategies, mainly based on surgical procedures and/or chronic administration of somatostatin analogues, show modest benefits, with liver transplantation as the only potentially curative option. Increasing research has shed light on the genetic landscape of PLDs and consequent cholangiocyte abnormalities, which can pave the way for discovering new targets for therapy and the design of novel potential treatments for patients. Herein, we provide a critical and comprehensive overview of the latest advances in the field of PLDs, mainly focusing on genetics, pathobiology, risk factors and next-generation therapeutic strategies, highlighting future directions in basic, translational and clinical research.

DOI: https://doi.org/10.1038/s41575-022-00617-7
FASEB J. 2022 May;36 Suppl 1

Calcium-dependent signaling via gap junctions drives RhoA/ROCK activation during collective cell migration.

Allison E Mancini, Megan A Rizzo.

Collective cell migration (CCM) plays an important role in embryogenesis, vascular sprouting, and wound healing, but is also a significant driver of cancer metastasis. Ras homolog family member A (RhoA) facilitates CCM by modulating contraction of the actomyosin cytoskeleton. Given the precise spatiotemporal regulation of RhoA during CCM, we wanted to investigate the activity of downstream effector Rho-associated kinase (ROCK) in collectively migrating fibroblasts. Using a new FRET-based ROCK biosensor, we have observed calcium-dependent activation of ROCK. We have previously demonstrated blunting of CCM in response to pharmacological inhibition of ROCK or depletion of intracellular calcium with 100 µM EGTA. To study the role of gap junction signaling in calcium-dependent activation of ROCK during CCM, carbenoxolone, a gap junction blocker, was applied to collectively migrating cells following scratch wounding. Carbenoxolone treatment blunted CCM, as well as decreased ROCK activity and intracellular calcium levels at corresponding time points. Treatment with PQ7, a gap junction activator, caused modest increases in CCM. These results indicate that calcium signaling through gap junctions drives ROCK activity in the context of collective cell migration.

DOI: https://doi.org/10.1096/fasebj.2022.36.S1.R4213
FASEB J. 2022 May;36 Suppl 1

Effects of flow and polycystin-1 dysfunction on ATP release in the inner medullary collecting duct of the kidney.

Wouter H van Megen, Charlotte R van Waes, Dorien J Peters, Jenny van der Wijst, Joost G Hoenderop.

After filtration of blood by the kidney, the remaining pro-urine flows through the renal tubular system with a flow rate that can vary considerably. These variations in pro-urinary flow can be sensed by mechanosensing proteins on the epithelial cells lining the renal tubules. An important mechanosensing protein is polycystin-1 (PC1), which is thought to be a key sensor of fluid flow. Mutations in PC1 give rise to autosomal dominant polycystic kidney disease (ADPKD), which is characterized by the formation of fluid-filled cysts in the kidney. Previous research has highlighted a role for the ATP release channel pannexin-1 (PANX1) in the increased flow-induced ATP release in a Pkd1-/- cell model of the distal convoluted tubule. However, it remains unclear if other purinergic signaling components are also involved, especially in the collecting duct. Using the mouse inner medullary collecting duct 3 (mIMCD3) cell line in combination with microfluidic experiments, we show here that a similar flow-induced ATP release is present in Pkd1-/- mIMCD3 cells under low (0.32 mL/min) or high (1.27 mL/min) flow application for 1 minute compared to wildtype (WT) mIMCD3 cells. This is despite a six-fold increase in the expression of Panx1 observed in Pkd1-/- mIMCD3 cells. Moreover, application of the specific PANX1-inhibitor BB-FCF revealed that PANX1 did not drive the high flow-induced increased ATP release. Accordingly, intermediate flow application (0.47 mL/min) for 3 hours did not increase Panx1 expression in WT mIMCD3 cells compared to the static condition. Flow did not increase the expression of any of the known purinergic receptors in the collecting duct cells compared to the static condition. We did observe a two-fold increase in gene expression of the putative ATP release channel connexin-30.3 (CX30.3) compared to static conditions. Moreover, we also report a three-fold increase in CX30.3 gene expression in Pkd1-/- mIMCD3 cells compared to WT cells. In conclusion, we show here that flow-induced purinergic signaling in the collecting duct greatly differs from previously published work on the distal convoluted tubule. Specifically, in the inner medulla of the collecting duct, PANX1 may not be the key flow-regulated ATP release channel. Instead, CX30.3 may facilitate flow-induced ATP release in this segment in health and in ADPKD.

DOI: https://doi.org/10.1096/fasebj.2022.36.S1.R3455
FASEB J. 2022 May;36 Suppl 1

Afferent Renal Nerve Activity is Proportionately Increased with Cystic Progression in a Preclinical Model of Autosomal Recessive Polycystic Kidney Disease.

Madeline Gauthier, Melissa Dennis, Mark Morales, Christopher T Banek.

Polycystic kidney disease (PKD) is the most common genetic cause of kidney failure, though the mechanisms underlying cyst formation and disease progression remain unclear. Innervation of the kidney contributes to the pathology of other cardiorenal dysfunction, including hypertension and chronic kidney disease - frequent complications of PKD. In previous studies, we demonstrated renal denervation (RDNX), either total or afferent-targeted (sensory) nerve ablation, reduced cystogenesis in a rat model of autosomal recessive PKD, thus highlighting a role for renal afferent nerves in PKD renal cystogenesis. To further elucidate this novel relationship, we aimed to quantify the renal afferent nerve activity (ARNA) in the adult PCK rat compared to non-cystic controls. We hypothesized that ARNA would be elevated in the PCK rat compared to controls, and ARNA would directly correlate with renal cystic severity. To address our hypothesis, we conducted direct afferent renal nerve recordings in 10-week-old PCK (n=15; 11M/4F) and age-matched Sprague-Dawley controls (SD; n=14; 6M/8F). Multiunit nerve recording was performed under isoflurane anesthesia by isolating and placing a renal nerve bundle on an iridium bipolar electrode, which was then encased in silicone. The nerve bundle was severed proximal to the electrode to isolate afferent renal nerve activity (ARNA). Following a 10-minute stabilization period, resting ARNA was recorded for 10 minutes. To permit comparison between animals, resting ARNA was normalized to a maximal stimulus, achieved by renal pelvic perfusion of 50 µM capsaicin. Finally, electrical noise was isolated by sectioning the distal end of the nerve bundle. Recordings were rectified and integrated over 50 ms. ARNA was expressed as a percentage of maximal ARNA. Following nerve recording, kidneys were collected, formalin fixed, and embedded in paraffin for histologic analysis of renal cystic index (CI). Kidneys were stained with Masson's Trichrome and analyzed using ImageJ, and CI was quantified by normalizing cystic area to the total kidney area. Data presented as mean ±SEM. Resting ARNA was higher in PCK (22.7±4.2%) rats compared to non-cystic SD controls (7.4±1.3%; Figure 1). Overall, PCK rats had an average CI of 8.7±0.7%. No sex differences in ARNA between male and female PCK rats were detected; however, CI was higher in male PCK rats (9.5±2.3%) compared to female PCK (6.3±1.9%). Further analysis of ARNA versus cystic index revealed a direct correlation between ARNA and renal cystic severity (F=5.9; R=0.61; p<0.05; Figure 2). These findings support our hypothesis that ARNA is elevated in the PCK rat. Importantly, ARNA is directly correlated with cystic progression in this model. To our knowledge, this study is the first to directly measure ARNA in this model of ARPKD, as well as to compare ARNA to cyst severity. These findings, combined with our previous studies, lead us to conclude that increased ARNA may directly contribute to the progression of PKD in this model. Presently, these data are limited to single endpoint observations. We are currently conducting additional studies to further dissect the temporal relationship between ARNA and renal cyst development. Our future studies will investigate the stimuli amplifying ARNA in a continued effort to parse the role of this novel neural-renal axis in the pathogenesis of PKD.

DOI: https://doi.org/10.1096/fasebj.2022.36.S1.R5527
FASEB J. 2022 May;36 Suppl 1

The role of primary cilia in pulmonary hypertension.

Philip Solymosi, Paul-Lennard Perret, Kathleen Gallo, Katharina Sinn, Walter Klepetko, Grazyna Kwapiszewska, Robert Preissner, Wolfgang M Kuebler.

INTRODUCTION: Vascular remodeling in pulmonary hypertension (PH) is characterized by endothelial dysfunction and smooth muscle cell proliferation and hypertrophy ultimately causing right heart failure and death. Up to now, the molecular mechanisms of PH pathogenesis have not been fully resolved, preventing the development of novel therapies against PH. Based on increased expression and activity levels in both patients and animal models with PH, respectively, PDGF-BB, TGF-β and mTOR signaling have been proposed to play critical roles as drivers of lung vascular remodeling. Among other effects, PDGF-BB, TGF-β and mTOR signaling cause shortening of the primary cilium - an antenna-like organelle that functions as a flow-sensor and signaling hub. Loss or shortening of cilia is characteristically associated with cell proliferation and promotes mTOR signaling, thus potentially establishing a positive feedback loop. Here, we hypothesized that PH is associated with a loss of primary cilia in pulmonary artery endothelial (PAECs) and smooth muscle cells (PASMCs) which in turn drives cell proliferation and thus, remodeling in the pulmonary arterial wall.
METHODS: Pulmonary artery tissue from PH-patients and non-PH donors was fixed and stained for acetylated α-tubulin to determine the number of primary cilia. PAECs and PASMCs from PH patients and non-PH donors were exposed in vitro to three different characteristic stimuli or mediators, respectively, of PH, namely PDGF-BB, TGF-β1, or hypoxia (1%). Cells were fixed and stained for measurement of primary cilia length. IFT88 - an essential structural protein of the primary cilium - was knocked down by siRNA in PAECs and PASMCs to assess the effect of cilium loss on migration and proliferation. Mice with an endothelial-specific deletion of IFT88 (Cdh5-CreERT2+ , IFT88fl/fl ) were housed for 5 weeks in normoxia or hypoxia (10% O2 ) to test for the role of endothelial primary cilia in the development of PH.
RESULTS: In pulmonary arteries of PH patients, the number of primary cilia per area was reduced by 80% as compared to healthy donor lungs. Analogously, PASMCs from PH patients had shorter cilia. Following IFT88 knock-down, PAECs and PASMCs showed increased migration and proliferation as compared to control cells. In both PAECs and PASMCs, stimulation with PDGF-BB, TGF-β1, or hypoxia shortened primary cilia as compared to controls. Mice lacking primary cilia in endothelial cells showed a significant increase in right ventricular systolic pressure after 5 weeks of hypoxia as compared to control mice.
CONCLUSIONS: Here, we demonstrate that PH is associated with a loss of cilia in vivo and reduced cilium length in vitro. Primary cilium loss promotes proliferation and migration of PAECs and PASMCs in vitro, as well as the development of PH in vivo. Cilium loss may as such be an important propagator of vascular remodeling in PH and may present a target for novel therapeutic interventions.

DOI: https://doi.org/10.1096/fasebj.2022.36.S1.R5226
J Cell Sci. 2022 May 01. pii: jcs259209. [Epub ahead of print]135(9):

Cilia-localized GID/CTLH ubiquitin ligase complex regulates protein homeostasis of sonic hedgehog signaling components.

Friederike Hantel, Huaize Liu, Lisa Fechtner, Herbert Neuhaus, Jie Ding, Danilo Arlt, Peter Walentek, Pablo Villavicencio-Lorini, Christoph Gerhardt, Thomas Hollemann, Thorsten Pfirrmann.

  Cilia are evolutionarily conserved organelles that orchestrate a variety of signal transduction pathways, such as sonic hedgehog (SHH) signaling, during embryonic development. Our recent studies have shown that loss of GID ubiquitin ligase function results in aberrant AMP-activated protein kinase (AMPK) activation and elongated primary cilia, which suggests a functional connection to cilia. Here, we reveal that the GID complex is an integral part of the cilium required for primary cilia-dependent signal transduction and the maintenance of ciliary protein homeostasis. We show that GID complex subunits localize to cilia in both Xenopus laevis and NIH3T3 cells. Furthermore, we report SHH signaling pathway defects that are independent of AMPK and mechanistic target of rapamycin (MTOR) activation. Despite correct localization of SHH signaling components at the primary cilium and functional GLI3 processing, we find a prominent reduction of some SHH signaling components in the cilium and a significant decrease in SHH target gene expression. Since our data reveal a critical function of the GID complex at the primary cilium, and because suppression of GID function in X. laevis results in ciliopathy-like phenotypes, we suggest that GID subunits are candidate genes for human ciliopathies that coincide with defects in SHH signal transduction.

Keywords:  AMPK; Ciliopathies; Cilium; GID complex; Sonic hedgehog; Ubiquitin

DOI:  https://doi.org/10.1242/jcs.259209
FASEB J. 2022 May;36 Suppl 1

Uncovering the Ciliogenesis Regulatory Network.

Hannah M Wesselman, Rebecca Wingert.

Ciliopathies comprise disorders associated with aberrant function of essential organelles called cilia. Cilia are found in almost all vertebrate cells, with a subset of this population being motile and/or multiciliated. Over 1,000 proteins have been associated with the ciliary proteome, yet the regulatory circuit controlling the formation of cilia remains lesser known. Our lab has identified transcription factors and coactivators that contribute to the ciliogenesis circuit. Such factors include orphan nuclear receptor Esrrγ and coactivator Ppargc1a/PGC1a. Independently, these factors regulate both mono- and multi-ciliated cells in the early signaling node, ear, and embryonic kidney (pronephros). Absence of these factors results in decreased multiciliated cells, decreased cilia length, and increased unciliated basal bodies. Considering these phenotypic similarities, we hypothesized a cooperative relationship between Esrrγ and Pppargc1a in the context of ciliated cell development. By modelling dual heterozygosity with genetic interaction studies, we found that ppargc1aworks synergistically with esrrγato regulate prostaglandin signaling to support ciliary outgrowth and multiciliated cell fate choice. While previous studies have alluded to the interaction of Esrrγ and Ppargc1a/PGC1a in metabolism, this is the first report of a cooperative effect that is essential for ciliogenesis or lineage decisions in development. This study has far-reaching implications, as cilia are present in various tissues, and these factors may serve as therapeutic targets for ciliopathic conditions and birth defects.

DOI: https://doi.org/10.1096/fasebj.2022.36.S1.R2013
Case Rep Gastroenterol. 2022 Jan-Apr;16(1):16(1): 201-208

Effectiveness of Open Fenestration for Autosomal Dominant Polycystic Liver Disease.

Luiz Fernando Norcia, Erika Mayumi Watanabe, Claudia Nishida Hasimoto, Leonardo Pelafsky, Walmar Kerche de Oliveira, Ligia Yukie Sassaki.

  Autosomal dominant polycystic liver disease (ADPLD) is a rare disease with variable clinical presentations, characterized by cystic enlargement of the liver. The diagnosis is made based on family history, patient's age, and liver phenotype and is confirmed by imaging tests. The treatment aims to reduce symptoms caused by the increased liver volume and can be performed by aspiration with sclerotherapy, fenestration, and liver resection. Although ADPLD is a rare disease, it is an important differential diagnosis of cystic diseases such as polycystic kidney disease; therefore, the aim of this article was to present the diagnostic and therapeutic approach of a case of ADPLD and conducting a literature review. This is the case of a 32-year-old male patient, who was hospitalized due to abdominal pain, hepatomegaly, lack of appetite, and weight loss. Imaging propaedeutics showed a significant increase in the liver volume due to hepatic cysts. After a multidisciplinary evaluation, given the clinical changes and the location of the hepatic cysts, fenestration was performed by laparotomy. The postoperative period was uneventful. The treatment was efficient in promoting symptomatic relief and improving the quality of life in this patient. Case reports on this disease are quite limited in the currently available literature, and there are gaps in knowledge with regard to the diagnosis and management of ADPLD. The importance of this article is that it will highlight the limitations in treatment options and allow physicians to make a more informed decision when diagnosing and treating a patient with ADPLD in the future.

Keywords:  Case report; Hepatic cysts; Hepatomegaly; Laparotomy fenestration; Polycystic liver disease

DOI:  https://doi.org/10.1159/000523662
FASEB J. 2022 May;36 Suppl 1

SPECC1L deficiency causes shortened primary cilia and genetically interacts with IFT-A deficiency to affect palatogenesis.

Brittany M Hufft-Martinez, Jeremy P Goering, Marta Stestiv, Michael J Moedritzer, Henry H Wang, Pamela V Tran, Irfan Saadi.

Orofacial clefts are among the most common congenital malformations, affecting approximately 1 in 700 births. SPECC1L mutations in patients with syndromic cleft lip and/or palate cluster in the second coiled coil domain (CCD2), which facilitates interaction of SPECC1L with microtubules. We have shown that loss of SPECC1L in a null allele (Specc1l∆Ex4 ) resulted in perinatal lethality and delayed palatal shelf elevation, but no cleft palate (CP) or exencephaly at birth. However, mice with an in-frame deletion of SPECC1L-CCD2 exhibited CP and exencephaly, which are common manifestations of ciliopathies. Given that SPECC1L cytoplasmic expression includes localization around the cilia base and that SPECC1L regulates actin cytoskeleton, we investigated an association between SPECC1L and primary cilia. We observed that primary cilia were shortened relative to wild-type in E13.5 Specc1l∆Ex4/∆Ex4 as well as Specc1l∆CCD2/∆CCD2 mutant palatal mesenchyme and epithelium. The cytoplasmic expression of SPECC1L around the cilia base was diminished in Specc1l∆CCD2/∆CCD2 cells. Thus, loss of SPECC1L association with microtubules appears sufficient to prevent its pericentriolar localization and to cause cilia shortening. Super-resolution imaging for acetylated-α-tubulin and ciliary membrane protein, ARL13B, revealed bulbous structures in Specc1l mutant cilia, suggesting a defect in ciliary protein trafficking. Due to the overlapping phenotypes of shortened cilia, exencephaly and CP between the intraflagellar transport (IFT)-A mouse mutant, Thm1aln/aln , and Specc1l∆CCD2/∆CCD2 , we crossed these mutants to look for a genetic interaction. 18% of Specc1l∆CCD2/+ , 0% of Thm1aln/+ , and 33% of double heterozygous Specc1l∆CCD2/+ ;Thm1aln/+ embryos showed CP, confirming a genetic interaction. This was observed when the mother was Specc1l∆CCD2/+ . However, remarkably, if the mother was Thm1aln/+ , there was no CP incidence in Specc1l∆CCD2/+ and Specc1l∆CCD2/+ ;Thm1aln/+ embryos even though they had shortened cilia, suggesting Thm1aln/+ mothers provided a protective environment against CP phenotype. Consistent with our previous data, Specc1l∆Ex4 ;Thm1aln/+ mice resulted in no CP. These results suggest that shortened cilia inSpecc1l mutants do not cause but rather modulate CP phenotype. Overall, our studies indicate a novel role for SPECC1L in ciliogenesis, a novel genetic interaction between Specc1l andThm1, and a novel protective maternal genetic effect of Thm1 in palatogenesis.

DOI: https://doi.org/10.1096/fasebj.2022.36.S1.R5795
Cells. 2022 May 05. pii: 1559. [Epub ahead of print]11(9):

The Cytoskeleton Effectors Rho-Kinase (ROCK) and Mammalian Diaphanous-Related (mDia) Formin Have Dynamic Roles in Tumor Microtube Formation in Invasive Glioblastoma Cells.

Kathryn N Becker, Krista M Pettee, Amanda Sugrue, Kevin A Reinard, Jason L Schroeder, Kathryn M Eisenmann.

  Glioblastoma (GBM) is a progressive and lethal brain cancer. Malignant control of actin and microtubule cytoskeletal mechanics facilitates two major GBM therapeutic resistance strategies-diffuse invasion and tumor microtube network formation. Actin and microtubule reorganization is controlled by Rho-GTPases, which exert their effects through downstream effector protein activation, including Rho-associated kinases (ROCK) 1 and 2 and mammalian diaphanous-related (mDia) formins (mDia1, 2, and 3). Precise spatial and temporal balancing of the activity between these effectors dictates cell shape, adhesion turnover, and motility. Using small molecules targeting mDia, we demonstrated that global agonism (IMM02) was superior to antagonism (SMIFH2) as anti-invasion strategies in GBM spheroids. Here, we use IDH-wild-type GBM patient-derived cell models and a novel semi-adherent in vitro system to investigate the relationship between ROCK and mDia in invasion and tumor microtube networks. IMM02-mediated mDia agonism disrupts invasion in GBM patient-derived spheroid models, in part by inducing mDia expression loss and tumor microtube network collapse. Pharmacological disruption of ROCK prevented invasive cell-body movement away from GBM spheres, yet induced ultralong, phenotypically abnormal tumor microtube formation. Simultaneously targeting mDia and ROCK did not enhance the anti-invasive/-tumor microtube effects of IMM02. Our data reveal that targeting mDia is a viable GBM anti-invasion/-tumor microtube networking strategy, while ROCK inhibition is contraindicated.

Keywords:  Rho-kinase; actin; cytoskeleton; glioblastoma; invasion; mDia formin; tumor microtube

DOI:  https://doi.org/10.3390/cells11091559
FASEB J. 2022 May;36 Suppl 1

Loss of ciliary adenylyl cyclase 3 in the ventromedial hypothalamus resulted in a sex-dependent obese phenotype.

Guorui Deng, Kenji Saito, Uday Singh, Yue Deng, Jacob Dickey, Jingwei Jiang, Huxing Cui.

Obesity, a metabolic disorder characterized by an excessive accumulation of body fat, continues to be a major economic and health burden to the global populace, as it is the most significant risk factor for heart disease, diabetes, and hypertension. Genome-wide association studies have identified several genes involved in obesity development, including ADCY3, a gene encoding for the enzyme adenylyl cyclase 3 (AC3). AC3 is a critical mediator of the cyclic adenosine monophosphate (cAMP) signaling pathway and is enriched in the primary cilium, a solitary immotile organelle protruding from most mammalian cells, including neurons. The primary cilia act as the cellular antenna to sense and relay changes in the extracellular microenvironment and mounting evidence support a role for the primary cilia as a critical regulator of the energy homeostasis. Patients carrying loss-of-function ADCY3variants are obese and are at increased risk of developing type II diabetes mellitus (T2DM). Consistently, whole-body Adcy3knockout mice also develop obesity; however, the underlying mechanisms by which AC3 affects metabolic homeostasis remain unclear. Here, we examined the impact of AC3 loss within the ventromedial nucleus of hypothalamus (VMH), a brain region critical for coordinated control of energy and glucose homeostasis, on energy metabolism. We generated mice with VMH-specific Adcy3loss (Adcy3SF-1KO mice) by crossing SF-1 Cre+ mice with Adcy3F/F mice and subjected them to metabolic phenotyping to assess energy balance and glucose homeostasis. We observed a sexually dimorphic effect on body weight under standard chow diet; male Adcy3SF-1KO mice displayed normal body weight gain comparable to control littermates, whereas female Adcy3SF-1KO mice gained a significant more weight compared to control littermates (Con 24.34g v KO 30.61g, p < 0.0001). Strikingly, however, both sexes of Adcy3SF-1KOmice exhibited improved glucose tolerance (AUC: M Con 17,826 v KO 15,165, p = 0.02; F Con 15,263 v KO 13,238, p = 0.03) without affecting fed and overnight fasting blood glucose levels. Taken together, these results underscore the importance of AC3-mediated ciliary cAMP signaling in VMH neurons for the regulation of energy balance and glucose homeostasis in a sex-dependent manner.

DOI: https://doi.org/10.1096/fasebj.2022.36.S1.R2878
FASEB J. 2022 May;36 Suppl 1

Inhibiting ADAM10-MMP14 Complex Blocks Cystogenesis of Kidney Epithelial Cells.

Frank Xu, Li-Lun Ho, You-Hsien H Lin, Tzongshi Lu.

BACKGROUND: Polycystic kidney disease (PKD) is the most common genetic kidney disorder. It is characterized by the aberrant renal tubule epithelial cells proliferation leads to the formation of multiple fluid-filled cysts, and it causes renal failure. Currently, kidney transplant or dialysis is the only effective treatment. A disintegrin-like metalloproteinase 10 (ADAM10) and matrix metalloproteinase 14 (MMP14) are two major members in the superfamily of metalloproteinases that primarily cleave several cell membrane proteins and growth factors. Inhibition of ADAM10 activity reduces cystic growth of renal epithelial cells, and inhibition of MMP14 also reduces the number of cysts in the kidneys of rats with PKD. In our study, we propose to elucidate the unclear relationship between ADAM10 and MMP14 in the development of cystogenesis in kidney.
METHODS: Madin-Darby Canine Kidney (MDCK) cells with stable expression of MMP14 and its mutants were developed and used in our study. MTT proliferation assay was used to measure cell growth. Immunoprecipitation and Western blots were used to determine physical association and proteinase activity. 3-dimensional (3D) culture of MDCK cells was used to examine cell growth patterns.
RESULTS: We found that a unique ADAM10-MMP14 complex forms in cell membrane. The hemopexin domain of MMP14 is essential for its association with ADAM10. Their interaction causes differential cleavage of cell membrane proteins, E-cadherin and L1 cell adhesion molecule protein (L1CAM). In MDCK cells, only ADAM10 cleaves E-cadherin but its cleavage is dependent on the active form of MMP14. In addition, both ADAM10 and MMP14 cleave L1CAM but inactive MMP14 blocks the ADAM10 cleavage of L1CAM. We tested the effects of ADAM10 and MMP14 interaction on cell proliferation and cystic growth. Ectopic expression of MMP14 increases cell proliferation and cystic growth of MDCK cells in a 3D culture matrix. Further, use of MMP14-specific inhibitor NSC405020 or ectopic expression of a dominant-negative form of MMP14 mutant also results in proper contact inhibition, and further promotes tubular growth of MDCK cells in 3D culture. Inhibition of ADAM10 with siRNA or enzymatic inhibitor GI254023X significantly reduces cell proliferation and promotes tubular growth. Combined use of GI254023X and NSC405020 results in a 73.4 ±8.23% decrease in cell proliferation compared to GI254023X, and 68.6 ± 6.84% decrease compared to NSC405020 alone. In 3D culture, MDCK-MMP14 (ectopic expression of MMP14) cells form cystic growth only, but addition of both ADAM10 and MMP14 inhibitors leads to tubular growth only.
CONCLUSION: Our data identified the solid physical association of ADAM10 and MMP14. Their functional interaction causes differential cleavage of cell membrane proteins, E-cadherin and L1CAM. Inhibition of ADAM10-MMP14 complex blocks proliferation and the cystogenesis of of kidney epithelial cells. Individual ADAM10 or MMP14 inhibitors have been used in clinical trials for certain tumors, however, they have never been used together nor have been used in PKD treatments. Our results suggest the combination of ADAM10 and MMP14 inhibitors could be served as a novel effective therapeutic strategy of PKD.

DOI: https://doi.org/10.1096/fasebj.2022.36.S1.R3162
Ren Fail. 2022 Dec;44(1): 790-805

Role of abnormal energy metabolism in the progression of chronic kidney disease and drug intervention.

Xuyan Liu, Huasheng Du, Yan Sun, Leping Shao.

  Chronic kidney disease (CKD) is a severe clinical syndrome with significant socioeconomic impact worldwide. Orderly energy metabolism is essential for normal kidney function and energy metabolism disorders are increasingly recognized as an important player in CKD. Energy metabolism disorders are characterized by ATP deficits and reactive oxygen species increase. Oxygen and mitochondria are essential for ATP production, hypoxia and mitochondrial dysfunction both affect the energy production process. Renin-angiotensin and adenine signaling pathway also play important regulatory roles in energy metabolism. In addition, disturbance of energy metabolism is a key factor in the development of hereditary nephropathy such as autosomal dominant polycystic kidney disease. Currently, drugs with clinically clear renal function protection, such as Angiotensin II Type 1 receptor blockers and fenofibrate, have been proven to improve energy metabolism disorders. The sodium-glucose co-transporter inhibitors 2 that can mediate glucose metabolism disorders not only delay the progress of diabetic nephropathy, but also have significant protective effects in non-diabetic nephropathy. Hypoxia-inducible factor enhances ATP production to the kidney by improving renal oxygen supply and increasing glycolysis, and the mitochondria targeted peptides (SS-31) plays a protective role by stabilizing the mitochondrial inner membrane. Moreover, several drugs are being studied and are predicted to have potential renal protective properties. We propose that the regulation of energy metabolism represents a promising strategy to delay the progression of CKD.

Keywords:  Energy metabolism; chronic kidney disease; drug intervention; hypoxia; mitochondrial dysfunction

DOI:  https://doi.org/10.1080/0886022X.2022.2072743
Zhong Nan Da Xue Xue Bao Yi Xue Ban. 2022 Jan 28. pii: 1672-7347(2022)01-0116-07. [Epub ahead of print]47(1): 116-122

Clinical phenotypes of primary ciliary dyskinesia.

Cheng Lei, Rongchun Wang, Danhui Yang, Ting Guo, Hong Luo.

  Primary ciliary dyskinesia (PCD) is a hereditary disease characterized by airway mucociliary clearance dysfunction. The estimated prevalence of PCD is 1꞉10 000 to 1꞉20 000. The main respiratory manifestations in children are cough, expectoration, chronic rhinitis, sinusitis, and chronic otitis media, while the most common symptoms in adults are chronic sinusitis, bronchiectasis, and infertility. About 50% of patients with certain PCD-related gene variants are combined with situs inversus, and the incidence of congenital heart disease is also high. The pathogenesis behind PCD is that gene variants cause structural or functional disorders of respiratory cilia and motile cilia of other organs, leading to a series of heterogeneous clinical manifestations, which makes it difficult to identify and diagnose PCD. Combining different disease screening tools and understanding the relationship between genotypes and phenotypes may facilitate early diagnosis and treatment for PCD.

Keywords:  clinical phenotype; disease screening; genotype; motile ciliopathies; primary ciliary dyskinesia

DOI:  https://doi.org/10.11817/j.issn.1672-7347.2022.210379