IL-1β Suppresses the Formation of Osteoclasts by Increasing OPG Production via an Autocrine Mechanism Involving Celecoxib-Related Prostaglandins in Chondrocytes

Elevated interleukin (IL)-1 concentrations in synovial fluid have been implicated in joint bone and cartilage destruction. Previously, we showed that IL-1β stimulated the expression of prostaglandin (PG) receptor EP4 via increased PGE2 production. However, the effect of IL-1β on osteoclast formation via chondrocytes is unclear. Therefore, we examined the effect of IL-1β and/or celecoxib on the expression of macrophage colony-stimulating factor (M-CSF), receptor activator of NF-κB ligand (RANKL), and osteoprotegerin (OPG) in human chondrocytes, and the indirect effect of IL-1β on osteoclast-like cell formation using RAW264.7 cells. OPG and RANKL expression increased with IL-1β; whereas M-CSF expression decreased. Celecoxib blocked the stimulatory effect of IL-1β. Conditioned medium from IL-1β-treated chondrocytes decreased TRAP staining in RAW264.7 cells. These results suggest that IL-1β suppresses the formation of osteoclast-like cells via increased OPG production and decreased M-CSF production in chondrocytes, and OPG production may increase through an autocrine mechanism involving celecoxib-related PGs

Prenatal diagnosis of severe mitochondrial diseases caused by nuclear gene defects: a study in Japan

Prenatal diagnoses of mitochondrial diseases caused by defects in nuclear DNA (nDNA) or mitochondrial DNA have been reported in several countries except for Japan. The present study aimed to clarify the status of prenatal genetic diagnosis of mitochondrial diseases caused by nDNA defects in Japan. A comprehensive genomic analysis was performed to diagnose more than 400 patients, of which, 13 families (16 cases) had requested prenatal diagnoses. Eight cases diagnosed with wild type homozygous or heterozygous variants same as either of the heterozygous parents continued the pregnancy and delivered healthy babies. Another eight cases were diagnosed with homozygous, compound heterozygous, or hemizygous variants same as the proband. Of these, seven families chose to terminate the pregnancy, while one decided to continue the pregnancy. Neonatal- or infantile-onset mitochondrial diseases show severe phenotypes and lead to lethality. Therefore, such diseases could be candidates for prenatal diagnosis with careful genetic counseling, and prenatal testing could be a viable option for families

Establishment of sandwich ELISA for soluble alpha-Klotho measurement: Age-dependent change of soluble alpha-Klotho levels in healthy subjects

Background α-Klotho (αKl) regulates mineral metabolism such as calcium ion (Ca2+) and inorganic phosphate (Pi) in circulation. Defects in mice result in clinical features resembling disorders found in human aging. Although the importance of transmembrane-type αKl has been demonstrated, less is known regarding the physiological importance of soluble-type αKl (sαKl) in circulation. Objectives The aims of this study were: (1) to establish a sandwich ELISA system enabling detection of circulating serum sαKl, and (2) to determine reference values for sαKl serum levels and relationship to indices of renal function, mineral metabolism, age and sex in healthy subjects. Results We successively developed an ELISA to measure serum sαKl in healthy volunteers (n = 142, males 66) of ages (61.1 ± 18.5 year). The levels (mean ± SD) in these healthy control adults were as follows: total calcium (Ca; 9.46 ± 0.41 mg/dL), Pi (3.63 ± 0.51 mg/dL), blood urea nitrogen (BUN; 15.7 ± 4.3 mg/dL), creatinine (Cre; 0.69 ± 0.14 mg/dL), 1,25 dihydroxyvitamin D (1,25(OH)2D; 54.8 ± 17.7 pg/mL), intact parathyroid hormone (iPTH; 49.2 ± 20.6 pg/mL), calcitonin (26.0 ± 12.3 pg/mL) and intact fibroblast growth factor (FGF23; 43.8 ± 17.6 pg/mL). Serum levels of sαKl ranged from 239 to 1266 pg/mL (mean ± SD; 562 ± 146 pg/mL) in normal adults. Although sαKl levels were not modified by gender or indices of mineral metabolism, sαKl levels were inversely related to Cre and age. However, sαKl levels in normal children (n = 39, males 23, mean ± SD; 7.1 ± 4.8 years) were significantly higher (mean ± SD; 952 ± 282 pg/mL) than those in adults (mean ± SD; 562 ± 146, P < 0.001). A multivariate linear regression analysis including children and adults in this study demonstrated that sαKl correlated negatively with age and Ca, and positively with Pi. Finally, we measured a serum sαKl from a patient with severe tumoral calcinosis derived from a homozygous missense mutation of α-klotho gene. In this patient, sαKl level was notably lower than those of age-matched controls. Conclusion We established a detection system to measure human serum sαKl for the first time. Age, Ca and Pi seem to influence serum sαKl levels in a normal population. This detection system should be an excellent tool for investigating sαKl functions in mineral metabolism

Seventh BHD international symposium: recent scientific and clinical advancement.

The 7th Birt-Hogg-Dubé (BHD) International Symposium convened virtually in October 2021. The meeting attracted more than 200 participants internationally and highlighted recent findings in a variety of areas, including genetic insight and molecular understanding of BHD syndrome, structure and function of the tumor suppressor Folliculin (FLCN), therapeutic and clinical advances as well as patients' experiences living with this malady

The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force

「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection

DOCK2 is involved in the host genetics and biology of severe COVID-19

「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target

Pediatric acute disseminated encephalomyelitis following asymptomatic coronavirus disease 2019

After the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic emerged, the virus spread rapidly worldwide, and outbreaks continued to occur intermittently. Here, we present the case of a 5-year-old boy with acute disseminated encephalomyelitis (ADEM) and initial symptoms of dysphoria and pain in the right lower extremity. Around the time of this episode, the patient exhibited no fever or respiratory symptoms. Brain magnetic resonance imaging (MRI) revealed multiple T2-weighted image/fluid-attenuated inversion recovery high-signal areas bilaterally subcortical to the deep white matter, corpus callosum, and bilateral basal ganglia. MRI of the cervical and thoracic regions indicated a long lesion with continuous T2WI high signal intensity in the central gray matter. Serum aquaporin-4 antibody and serum myelin oligodendrocyte glycoprotein antibody tests were negative and positive, respectively. A polymerase chain reaction test using nasopharyngeal swab fluid upon admission was positive for SARS-CoV-2. Patients with severe coronavirus disease 2019 (COVID-19) in the acute phase may show central nervous system symptoms. There have been no previous reports of ADEM in the subacute phase of COVID-19, lacking symptoms in the acute phase, as in the present case. Notably, ADEM can develop in the subacute phase of asymptomatic COVID-19 infection