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Objectives. The texture of the autologous platelet-rich plasma (PRP) that is used in treating degenerative joint diseases such as knee osteoarthritis (OA) is usually in liquid form. However, the turnover rate of protein metabolism in the knee synovial fluid (SF) is less than one hour. This study examined the feasibility of the thermal oscillation technique in converting the liquid-form PRP into an injectable viscous paste-like PRP that may delay the degradation of PRP and continuously release growth factors in the knee joint for a longer period of time. Methods. This study was conducted in the rehabilitation department of a tertiary hospital. A total of 10 elderly patients with an average age of greater than 65 years and diagnosed with moderate degree of knee OA were recruited. The RegenPRP (RegenLab, Le Mont-sur-Lausanne, Switzerland) test tube chamber was used for PRP generation. A total of 60 milliliters (mL) of blood was drawn from each patient. 10 mL of blood was injected into each PRP test tube chamber. As a result, a total of 6 test tube chambers were obtained and each chamber was centrifuged for 15 minutes. Approximately 5 mL of PRP supernatant (the liquid-form end product) was aspirated and sent for thermal oscillation treatment. Five temperatures were tested: 55, 65, 75, 85, and 95 degrees Celsius. Oscillation was set at 200 revolutions per minute (rpm) for 15 minutes. The enzyme-linked immunosorbent assay (ELISA) was applied in measuring the concentration of platelet-derived growth factor (PDGF) in picogram/milliliter (pg/mL). Repeated measures ANOVA followed by the Bonferroni post hoc test was used to compare the PDGF concentrations between each testing condition. Results. Under 75 degrees Celsius of heating, the resultant paste-like PRP end product had the highest concentration of PDGF in picograms per milliliter (pg/mL) as compared with other heating conditions ( p < 0.05 ). The viscosity of the paste-like PRP was measured to be 70,000 centipoise (cP), which is similar to the viscosity of a toothpaste. The paste-like PRP end product was able to release PDGF continuously for about 14 days, with the highest concentration achieved on the 8th day with an average of 35646 ± 2499 pg / mL . In nonthermally treated liquid-form PRP sample, the highest number of PRP was observed on the 4th day with an average value of 8444 ± 831 pg / mL . Under the heating conditions of 55 and 95 degrees Celsius, the highest concentration of PDGF was observed on the 5th day ( 13346 ± 764 pg / mL and 3440 ± 303 pg / mL , respectively). Under the heating conditions of 65 and 85 degrees Celsius, the highest concentration of PDGF was observed on the 7th day ( 15468 ± 744 pg / mL and 20432 ± 1118 pg / mL , respectively). Conclusion. Through thermal oscillation, liquid-form PRP can be converted to paste-like PRP end product with a viscosity similar to that of a toothpaste. The best heating condition was discovered to be 75 degrees Celsius. The paste-like PRP was able to release PDGF continuously for about 2 weeks, with the highest concentration obtained on the 8th day. The findings in this study suggested that paste-like PRP may be a viable option in treating degenerative knee joint diseases.

The aim of this study was to explore the rehabilitation experiences and perceptions of patients with neurological disorders who have used the Lokomat Augmented Feedback module, a robot-assisted gait training device.A qualitative descriptive study was conducted.Purposive sampling was employed to recruit participants with neurological disorders who have used the Lokomat. Semistructured face-to-face interviews were completed in northern Taiwan. Interviews were recorded and transcribed verbatim. Thematic analysis was used.Thirteen interviews were analyzed. Three themes were identified: learning to walk again, inspiring the fighting spirit, and the joys and worries of technological innovation.Strong positive emotions and logistical concerns were associated with the use of the Lokomat.Encouraging patients while also being transparent about the challenges involved in the rehabilitation process and helping set realistic goals is critical. Furthermore, attention directed toward anticipating and mitigating the physical strain associated with the Lokomat is important.

Objective. This present study aimed to explore the clinical effects of ultrasound-guided (USG) mechanical needling with sterile water injection for lumbar facet joint syndrome. Methods. This was a retrospective cohort study that assessed the clinical outcome of ageing patients who received USG mechanical needling with sterile water injection. In addition, the clinical outcome of age- and gender-matched patients randomly selected from patients who received mechanical needling with sterile water was compared to the patients injected with steroids in a 2 : 1 ratio. The data were extracted from the medical records of ageing patients with facet joint syndrome who received USG injection at the lumbosacral spine by the first author. Low back pain or axial pain, and leg pain or radicular pain were assessed by the visual analogue scale (VAS), and gait ability with walking distance was obtained at 6 different time points. Results. A total of 4,276 medical records were examined. Four thousand two hundred twenty-eight ageing patients received needling with sterile water injection and found that the efficacy lasted up to 6 months. Ninety-six patients were compared with 48 patients who received steroid injection. Those who received steroids had less back and leg pain at 1 week after injection; however, pain returned at 3 months and 6 months after injection. Conclusions. USG mechanical needling with sterile water could help relieve axial and radicular pain for at least 6 months. Reduced sensitization and removal of calcification and fibrosis were all possible mechanisms.Keywords: Mechanical needling, Sterile water, Ultrasound guided (USG) injection, Facet joint syndrome, Pain

Chromosomal instability (CIN) is a driving force for cancer development. The most common causes of CIN include the dysregulation of the spindle assembly checkpoint (SAC), which is a surveillance mechanism that prevents premature chromosome separation during mitosis by targeting anaphase-promoting complex/cyclosome (APC/C). DAB2IP is frequently silenced in advanced prostate cancer (PCa) and is associated with aggressive phenotypes of PCa. Our previous study showed that DAB2IP activates PLK1 and functions in mitotic regulation. Here, we report the novel mitotic phosphorylation of DAB2IP by Cdks, which mediates DAB2IP’s interaction with PLK1 and the activation of the PLK1-Mps1 pathway. DAB2IP interacts with Cdc20 in a phosphorylation-independent manner. However, the phosphorylation of DAB2IP inhibits the ubiquitylation of Cdc20 in response to SAC, and blocks the premature release of the APC/C-MCC. The PLK1-Mps1 pathway plays an important role in mitotic checkpoint complex (MCC) assembly. It is likely that DAB2IP acts as a scaffold to aid PLK1-Mps1 in targeting Cdc20. Depletion or loss of the Cdks-mediated phosphorylation of DAB2IP destabilizes the MCC, impairs the SAC, and increases chromosome missegregation and subsequent CIN, thus contributing to tumorigenesis. Collectively, these results demonstrate the mechanism of DAB2IP in SAC regulation and provide a rationale for targeting the SAC to cause lethal CIN against DAB2IP-deficient aggressive PCa, which exhibits a weak SAC.

Recent studies of postflutter limit-cycle oscillations (LCOs) have suggested the presence/effects of a nonlinear structural damping in addition to other potential sources of nonlinearity. Such a no...

Knee osteoarthritis (OA) is a common problem in elderly patients. They are often troubled with altered knee function, such as pain and weakness. However, not all these patients are able to receive autologous platelet-rich plasma (PRP) injections as they may be taking antiplatelet or anticoagulant medications. Their physical condition may not allow them to receive total knee replacement surgery as well. Long-term oral intake of nonsteroidal anti-inflammatory drugs may be detrimental to the gastrointestinal tract. As a result, it is crucial to discover new treatment options that can alleviate painful knee symptoms in elderly knee OA patients. In this study, 19 elderly patients diagnosed with moderate degree of knee OA as well as suprapatellar bursitis were recruited. They received low-level laser therapy (LLLT) to their affected knees. Under ultrasound guidance, flexible fiber optic wire was inserted intra-articularly into the knee joint. Red laser followed by infrared irradiation was performed once every 2 weeks for a total of 3 times. The Lequesne index for knee OA and the volume of suprapatellar synovial fluid (SF) were measured. SF proteomic analyses were also performed up to a period of 6 months. The results revealed that after 3 LLLT, the Lequesne index significantly decreased, signifying improvement in the knee joint functional status. The volume of suprapatellar SF and SF proteins associated with inflammation also decreased significantly in the SF. These findings lasted up to a period of at least 3 months. Therefore, LLLT may be considered as a feasible option in treating elderly patients with knee OA who are not suitable for surgical interventions or intra-articular PRP injections.

(1) Background: Severe traumatic brain injury (sTBI) is the leading cause of death in children. Serious extracranial injury (SEI) commonly coexists with sTBI after the high impact of trauma. Limited studies evaluate the influence of SEI on the prognosis of pediatric sTBI. We aimed to analyze SEI’s clinical characteristics and initial presentations and evaluate if SEI is predictive of higher in-hospital mortality in these sTBI children. (2) Methods: In this 11-year-observational cohort study, a total of 148 severe sTBI children were enrolled. We collected patients’ initial data in the emergency department, including gender, age, mechanism of injury, coexisting SEI, motor components of the Glasgow Coma Scale (mGCS) score, body temperature, blood pressure, blood glucose level, initial prothrombin time, and intracranial Rotterdam computed tomography (CT) score of the first brain CT scan, as potential mortality predictors. (3) Results: Compared to sTBI children without SEI, children with SEI were older and more presented with initial hypotension and hypothermia; the initial lab showed more prolonged prothrombin time and a higher in-hospital mortality rate. Multivariate analysis showed that motor components of mGCS, fixed pupil reaction, prolonged prothrombin time, and higher Rotterdam CT score were independent predictors of in-hospital mortality in sTBI children. SEI was not an independent predictor of mortality. (4) Conclusions: sTBI children with SEI had significantly higher in-hospital mortality than those without. SEI was not an independent predictor of mortality in our study. Brain injury intensity and its presentations, including lower mGCS, fixed pupil reaction, higher Rotterdam CT score, and severe injury-induced systemic response, presented as initial prolonged prothrombin time, were independent predictors of in-hospital mortality in these sTBI children.

Study Design: This was a retrospective observational study that assessed the clinical outcome of ageing patients who received ultrasound-guided (USG) mechanical needling with sterile water injection. In addition, the clinical outcome of age-and gender matched patients randomly selected from patients who received needling with sterile water was compared to the patients injected with lidocaine in a 1:1 ratio. Objective: This present study aimed to explore the clinical effects of USG mechanical needling with sterile water injection for lumbar spinal stenosis (LSS). Methods: The data was extracted from the medical records of ageing patients with LSS who received USG injection at the lumbosacral spine by the first author. Low back pain or axial pain, and leg pain or radicular pain were assessed by the visual analogue scale, and gait ability with walking distance were obtained at six different time points. Results: A total of 4328 medical records were examined. Four thousand two hundred and twenty-eight ageing patients received mechanical needling with sterile water injection and found the efficacy lasted up to 6 months. One hundred patients were compared with 100 patients who received lidocaine injection. Those who received lidocaine had pain returned at 3 months and 6 months post-injection. Conclusions: USG mechanical needling with sterile water injection could help relieve axial and radicular pain for at least 6 months. Removal of calcification and fibrosis as well as reduction of sensitization are all possible mechanisms.

In mammalian cells, extracellular vesicles (EVs) derived from the endosomal system carry many different kinds of bioactive molecule to deliver to recipient cells in a paracrine or endocrine manner. EVs can mediate local and systemic intercellular communications, including reeducating stromal cells, remodeling the architecture of the tumor microenvironment, modulating cancer metabolism and metastases, or even conferring drug resistance. Because the molecular and functional characteristics of prostate cancer (PCa) evolve over time, the bioactive molecule profiles/signatures of tumor-derived EVs (TDEs) reflect the real-time status of cancer cells. TDEs appear to be valuable diagnostic and prognostic biomarkers as well as potential therapeutic vehicles, suggesting their essential role in precision medicine of disease management. We summarized critical aspects of TDEs in PCa and discussed their potential clinical applications.

Grasping a non-cooperative “customer satellite” with a robotic arm is a challenging task for on-orbit services of spacecraft since the collision between the robot and the target is inevitable and the dynamic behaviors of the two objects are hard to control after the collision. To grasp successfully, the contact between the space robot and the target is hoped to be maintained after the collision. In this paper, the contact control problem for grasping a non-cooperative satellite is studied. First, to simulate the contact conditions as realistic as possible, the multibody dynamics, the modified Hertz contact, and the contact detection theory are employed to establish a grasping dynamics model. Then, based on the study on the dynamic behavior of the two-ball collision problem, a hybrid control scheme with damping and attitude tracking controllers is proposed. By this scheme, the control goal, i.e. maintaining the contact between the robot and the target, can be realized after multiple collisions. Finally, numerical simulations are performed to validate the proposed control scheme, and the results demonstrate its effectiveness in grasping a non-cooperative tumbling satellite.

This review focuses on DNA–dependent protein kinase (DNA–PK), which is the key regulator of canonical non–homologous end–joining (NHEJ), the predominant mechanism of DNA double–strand break (DSB) repair in mammals. DNA–PK consists of the DNA–binding Ku70/80 heterodimer and the catalytic subunit DNA–PKcs. They assemble at DNA ends, forming the active DNA–PK complex, which initiates NHEJ–mediated DSB repair. Paradoxically, both Ku and DNA–PKcs are associated with telomeres, and they play crucial roles in protecting the telomere against fusions. Herein, we discuss possible mechanisms and contributions of Ku and DNA–PKcs in telomere regulation.

Background and Objectives: Ankle foot orthoses (AFOs) are commonly used by stroke patients to walk safely and efficiently. Both posterior AFOs (PAFOs) and anterior AFOs (AAFOs) are available. The objective of this study was to compare the efficacy of AAFOs and PAFOs in the treatment of ankle spasticity. Materials and Methods: A crossover design with randomization for the interventions and blinded assessors was used. Twenty patients with chronic stroke, a Modified Ashworth Scale (MAS) score of the ankle joint of 2, and a Tardieu angle ≥20 degrees were recruited. The patients were assigned to wear either an AAFO or PAFO at random and subsequently crossover to the other AFO. Results: Twenty stroke patients with ankle spasticity were recruited. The mean age was 46.60 (38–60) years. The mean time since stroke onset was 9.35 (6–15) months. It was discovered that the AAFO improved walking speed as well as the stretch reflex dynamic electromyography (dEMG) and walking dEMG amplitudes of the medial gastrocnemius muscles more significantly than the PAFO (p < 0.05). Conclusions: The AAFO had greater efficacy in reducing both static and dynamic ankle spasticity, and allowed for faster walking than the PAFO. The stretch reflex and walking dEMG amplitudes could be used for quantitative spasticity assessment.

Lysophosphatidic acid (LPA) is a growth factor-like lipid mediator that regulates various physiological functions via activation of multiple LPA G protein-coupled receptors. We previously reported that LPA suppresses oxidative stress in premature aging Hutchinson-Gilford progeria syndrome (HGPS) patient fibroblasts via its type 3 receptor (LPA3). Mitochondria have been suggested to be the primary origin of oxidative stress via the overproduction of reactive oxygen species (ROS). Mitochondria are responsible for producing ATP through oxidative phosphorylation (OXPHOS) and have a calcium buffering capacity for the cell. Defects in mitochondria will lead to declined antioxidant capacity and cell apoptosis. Therefore, we aim to demonstrate the regulatory role of LPA3 in mitochondrial homeostasis. siRNA-mediated depletion of LPA3 leads to the depolarization of mitochondrial potential (ΔΨm) and cellular ROS accumulation. In addition, the depletion of LPA3 enhances cisplatin-induced cytochrome C releasing. This indicates that LPA3 is essential to suppress the mitochondrial apoptosis pathway. LPA3 is also shown to improve mitochondrial ADP-ATP exchange by enhancing the protein level of ANT2. On the other hand, LPA3 regulates calcium uptake from the ER to mitochondria via the IP3R1-VDAC1 channel. Moreover, activation of LPA3 by selective agonist OMPT rescues mitochondrial homeostasis of H2O2-induced oxidative stress cells and HGPS patient fibroblasts by improving mitochondrial ΔΨm and OXPHOS. In summary, our findings imply that LPA3 acts as the gatekeeper for mitochondrial healthiness to maintain cell youth. Furthermore, LPA3 can be a promising therapeutic target to prevent mitochondrial oxidative stress in aging and HGPS.

Nonambulatory stroke patients are extremely sedentary, but most available data concerning exercise training in stroke patients are related to ambulatory patients. This study aimed to investigate the efficacy of stepper-based exercise training on cardiopulmonary fitness, monocyte subtypes, and associated monocyte-platelet aggregates (MPA) and thrombin generation (TrG) in nonambulatory hemiplegic patients with ischemic stroke.Thirty-eight patients were randomized into exercise training (ET, n = 20) and usual care (UC, n = 18) groups. The ET underwent supervised exercise training (60% peak work rate) using a recumbent stepper for two to four sessions per week and 36 sessions in total. In addition, 12 healthy participants were enrolled as healthy controls. Monocyte characteristics, MPA, and plasma TrG kinetics were determined before and after intervention by flow cytometry and calibrated automated thrombogram® (CAT).Seventeen and 15 patients completed the protocol in the ET and UC groups. Peak V̇O2 improved in ET (15.7 ± 4.8 vs 18.9 ± 5.3 mL·min-1·kg-1, +20%), so did the phase angle of the hemiplegic limbs. The counts of total MPA and MPA associated with three monocyte subtypes, alongside CD42b expression all declined in ET with subtypes 2 and 1 being the most prominent. Macrophage inflammatory protein 1β (MIP-1 β) level also declined. The TrG kinetics was attenuated after ET by delaying initiation and reducing the rising slope and peak of thrombin production. In UC, no difference was revealed in the pre-post comparison.Stepper-based ET is feasible in nonambulatory hemiplegic patients and is effective in improving aerobic fitness. Moreover, it decreases heteroaggregation of monocytes with platelets, especially in monocyte subtypes 2 and 1. Thrombin generation was also attenuated. Hence, stepper-based ET may be incorporated in the rehabilitation of nonambulatory hemiplegic patients.

RNA polymerase II (Pol II)-dependent transcription in stimulus-inducible genes requires topoisomerase IIβ (TOP2B)-mediated DNA strand break and the activation of DNA damage response signalling in humans. Here, we report a novel function of the breast cancer 1 (BRCA1)-BRCA1-associated ring domain 1 (BARD1) complex in this process. We found that BRCA1 is phosphorylated at S1524 by the kinases ataxia-telangiectasia mutated and ATR during gene activation, and that this event is important for productive transcription. Our biochemical and genomic analyses showed that the BRCA1-BARD1 complex interacts with TOP2B in the EGR1 transcription start site and in a large number of protein-coding genes. Intriguingly, the BRCA1-BARD1 complex ubiquitinates TOP2B, which stabilizes TOP2B binding to DNA while BRCA1 phosphorylation at S1524 controls the TOP2B ubiquitination by the complex. Together, these findings suggest the novel function of the BRCA1-BARD1 complex in the regulation of TOP2B and Pol II-mediated gene expression.

The first stage of field experiments involving the design and construction of a low-power consumption ocean bottom electro-magnetometer (OBEM) has been completed. To improve the performance of the OBEM, we rigorously evaluated each of its units, e.g., the data loggers, acoustic parts, internal wirings, and magnetic and electric sensors, to eliminate unwanted events such as unrecovered or incomplete data. The evaluations of the procedure included the following. Data logger: digitizer sensitivity, linearity, and errors Acoustic transceiver: “ENABLE,” “DISABLE,” “RANGE,” “RELEASE1,” “RELEASE2,” and “OPTION1” functions Magnetic sensor: sensitivity of the fluxgate and orthogonality Electrical receiver: potential voltage, impedance, and frequency responses Power consumption: the maximum operating current of two sets of batteries Deployment and recovery procedures on deck We confirmed the optimal performance of the OBEM after repeatedly testing the procedures. The first offshore deployment of the OBEM together with ocean bottom seismographs (OBSs) was performed in NE Taiwan, where the water depth is approximately 1,400 m. The total intensity of the magnetic field (TMF) measured by the OBEM varied in the range of 44,100–44,150 nT, which corresponded to the proton magnetometer measurements. The daily variations of the magnetic field were recorded using the two horizontal components of the OBEM magnetic sensor. We found that the inclinations and magnetic data of the OBEM varied with two observed earthquakes when compared to the OBS data. The potential fields of the OBEM were slightly, but not obviously, affected by the earthquakes.

Purpose: Renal cell carcinoma (RCC) is known to be highly radioresistant but the mechanisms associated with radioresistance have remained elusive. We found DOC-2/DAB2 interactive protein (DAB2IP) frequently downregulated in RCC, is associated with radioresistance. In this study, we investigated the underlying mechanism regulating radioresistance by DAB2IP and developed appropriate treatment. Experimental Design: Several RCC lines with or without DAB2IP expression were irradiated with ionizing radiation (IR) for determining their radiosensitivities based on colony formation assay. To investigate the underlying regulatory mechanism of DAB2IP, immunoprecipitation-mass spectrometry was performed to identify DAB2IP-interactive proteins. PARP-1 expression and enzymatic activity were determined using qRT-PCR, Western blot analysis, and ELISA. In vivo ubiquitination assay was used to test PARP-1 degradation. Furthermore, in vivo mice xenograft model and patient-derived xenograft (PDX) model were used to determine the effect of combination therapy to sensitizing tumors to IR. Results: We notice that DAB2IP-deficient RCC cells acquire IR-resistance. Mechanistically, DAB2IP can form a complex with PARP-1 and E3 ligases that is responsible for degrading PARP-1. Indeed, elevated PARP-1 levels are associated with the IR resistance in RCC cells. Furthermore, PARP-1 inhibitor can enhance the IR response of either RCC xenograft model or PDX model. Conclusions: In this study, we unveil that loss of DAB2IP resulted in elevated PARP-1 protein is associated with IR-resistance in RCC. These results provide a new targeting strategy to improve the efficacy of radiotherapy of RCC.

Therapeutic drug synergism intervened in cancer treatments has been demonstrated to be more effective than using a single effector. However, it remains inherently challenging, with a limited cell count from tumor samples, to achieve potent personalized drug cocktails. To address the issue above, we herein present a nanodroplet cell processing platform. The platform incorporates an automatic nanodroplet dispenser with cell array ParaStamp chips, which were fabricated by a new wax stamping approach derived from laser direct writing. Such approach enables not only the on-demand de-wetting with hydrophobic wax films on substrates but also the mask-less fabrication of non-planar microstructures (i.e. no photolithography process). The ParaStamp chip was pre-occupied with anti-cancer drugs and their associate mixtures, enabling for the spatially addressable screening of optimal drug combinations simultaneously. Each droplet with a critical volume of 200 nl containing with 100 cells was utilized. Results revealed that the optimal combination reduces approximate 28-folds of conducted doses compared with single drugs. Tumor inhibition with the optimally selected drug combination was further confirmed by using PC-3 tumor-bearing mouse models. Together, the nanodroplet cell processing platform could therefore offer new opportunities to power the personalized cancer medicine at early-stage drug screening and discovery.

Background: Medical therapy is often prescribed to reduce the rate of aortic dilatation and prevent aortic dissection in patients with bicuspid aortic valve (BAV) despite a lack of evidence. We conducted an anonymous survey to gain insight into Canadian clinical practice regarding medical therapy used to slow the progression of aortic dilatation in patients with BAV. Methods: A questionnaire was sent to 115 paediatric cardiologists and 18 adult congenital heart disease specialists in Canada. Results: Ninety of 113 paediatric cardiologists (80%) completing the questionnaire reported prescribing medication to reduce the rate of aortic dilatation. Some 75% (61/81) of them reported prescribing medications on the basis of aortic size z scores, and 78% (48/61) considered medication at a z score between ≥ 2 and < 5. The remaining 25% of responders (20/81) reported prescribing medications on the basis of absolute aortic diameter, and 80% (16/20) of them considered initiating medical therapy at an aortic diameter > 40 mm to < 50 mm. For practical purposes, however, 40% of respondents (45/113) would not or rarely consider medical therapy for this indication because of variation in the threshold for initiating treatment. Ten of 14 adult congenital heart disease specialists’ responses (71%), reported prescribing medications who were excluded because of missing data. Conclusion: The majority of Canadian paediatric cardiologists reported prescribing medications to slow the rate of aortic dilatation in patients with BAV. However, there is heterogeneity in the criteria to prescribe medical therapy. A multicenter randomized controlled trial is needed to establish the role of medical therapy in this patient population. Résumé: Introduction: En dépit du manque de données probantes, un traitement médical est souvent prescrit pour réduire le taux de dilatation aortique et prévenir la dissection aortique chez les patients ayant une bicuspidie aortique (BA). Nous avons mené une enquête anonyme pour avoir un aperçu de la pratique clinique au Canada en ce qui concerne le traitement médical utilisé pour ralentir la progression de la dilatation aortique chez les patients ayant une BA. Méthodes: Nous avons envoyé un questionnaire à 115 cardiologues en pédiatrie et à 18 spécialistes en cardiopathie congénitale de l’adulte du Canada. Résultats: Quatre-vingt-dix des 113 cardiologues en pédiatrie (80 %) ayant rempli le questionnaire ont signalé prescrire des médicaments pour réduire le taux de dilatation aortique. Certains d’entre eux, soit 75 % (61/81) ont signalé prescrire des médicaments en fonction du Z-score de la taille aortique, et 78 % (48/61) ont envisagé de prescrire les médicaments lorsque le Z-score était entre ≥ 2 et < 5. Les 25 % de répondants restants (20/81) ont signalé prescrire des médicaments en fonction du diamètre aortique absolu, et 80 % (16/20) d’entre eux ont envisagé de faire commencer le traitement médical lorsque le diamètre aortique était entre > 40 mm et < 50 mm. Concrètement, toutefois, 40 % des répondants (45/113) n’ont pas envisagé ou ont rarement envisagé de prescrire un traitement médical pour cette indication en raison de la variation dans le seuil de mise en place du traitement. Dix des 14 réponses (71 %) des spécialistes de la cardiopathie congénitale de l’adulte ont signalé prescrire des médicaments qui étaient exclus en raison de données manquantes. Conclusion: La majorité des cardiologues en pédiatrie du Canada ont signalé prescrire des médicaments pour ralentir le taux de dilatation aortique chez les patients ayant une BA. Toutefois, les critères utilisés pour prescrire un traitement médical sont hétérogènes. Un essai clinique multicentrique et à répartition aléatoire est nécessaire pour déterminer le rôle du traitement médical dans cette population de patients.

(1) Background: To evaluate the clinical effects of leukocyte-rich platelet-rich plasma (LR-PRP) and hyaluronic acid (HA) injections in treating patients suffering from knee osteoarthritis (OA); (2) Methods: Randomized controlled trials (RCTs) were searched from PubMed, Web of Science, and Cochrane Library. Keywords were: platelet-rich plasma, LR-PRP, leukocyte-rich, hyaluronic acid, and knee osteoarthritis. The included RCTs were published between the 1st of November 2011 and the 3rd of February 2021. Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores, visual analog scale (VAS) scores, International Knee Documentation Committee (IKDC) scores, and adverse events were used as outcomes for evaluation; (3) Results: A total of 14 RCTs were enrolled. At 6 months, revealed that the LR-PRP group was better than the HA group in WOMAC total, pain, and physical function scores. At 12 months, the LR-PRP group was better than the HA group in WOMAC stiffness and physical function scores. There was no significant difference in adverse events; (4) Conclusion: LR-PRP injection showed no significant pain relief effect as compared with HA injection. However, LR-PRP demonstrated better overall outcomes as compared to HA in knee OA patients at the follow-up periods of 3, 6, and 12 months. LR-PRP injection may be recommended as a feasible option in treating patients with knee OA.

Purpose Harnessing the immune-stimulatory effects of radiation by combining it with immunotherapy is a promising new treatment strategy. However, more studies characterizing immunotherapy and radiation dose scheduling for the optimal therapeutic effect is essential for designing clinical trials. Methods and Materials A new ablative radiation dosing scheme, personalized ultrafractionated stereotactic adaptive radiation therapy (PULSAR), was tested in combination with α-PD-L1 therapy in immune-activated and resistant syngeneic immunocompetent mouse models of cancer. Specifically, tumor growth curves comparing immunotherapy and radiation therapy dose sequencing were evaluated in immunologically cold and hot tumor models. The response relative to cytotoxic killer T cells was evaluated using an α-CD8 depleting antibody, and immunologic memory was tested by tumor rechallenge of cured mice. Results We report that both radiation and immunotherapy sequencing, as well as radiation therapy fraction spacing, affect the combination treatment response. Better tumor control was achieved by giving α-PD-L1 therapy during or after radiation, and spacing fractions 10 days apart (PULSAR) achieved better tumor control than traditional daily fractions. We showed that CD8+ depleting antibody abrogated tumor control in the PULSAR combination treatment, and certain treatment schedules induced immunologic memory. Conclusions These results illustrate that radiation therapy dosing and scheduling affect tumor control, in combination with checkpoint blockade therapies. PULSAR-style radiation dosing is more complementary in combination with single-agent immunotherapy than traditional daily fractions in this preclinical model. Preclinical investigation could prove helpful in designing clinical trials investigating combination therapy.

Combining targeted therapeutic agents is an attractive cancer treatment strategy associated with high efficacy and low toxicity. DNA-dependent protein kinase catalytic subunit (DNA-PKcs) is an essential factor in DNA damage repair. Studies from us and others have revealed that DNA-PKcs also plays an important role in normal mitosis progression. Histone deacetylase (HDACs) inhibitors commonly lead to mitotic aberration and have been approved for treating various cancers in the clinic. We showed that DNA-PKcs depletion or kinase activity inhibition increases cancer cells’ sensitivity to HDACs inhibitors in vitro and in vivo. DNA-PKcs deficiency significantly enhances HDACs inhibitors (HDACi)-induced mitotic arrest and is followed by apoptotic cell death. Mechanistically, we found that DNA-PKcs binds to HDAC6 and facilitates its acetylase activity. HDACi is more likely to impair HDAC6-induced deacetylation of HSP90 and abrogate HSP90’s chaperone function on Aurora A, a critical mitotic kinase that regulates centrosome separation and mitotic spindle assembly in DNA-PKcs-deficient cells. Our current work indicates crosstalk between DNA-PKcs and HDACs signaling pathways, and highlights that the combined targeting of DNA-PKcs and HDACs can be used in cancer therapy. Abbreviations: DNA-PKcs, DNA-dependent protein kinase catalytic subunit, HDACs, Histone deacetylases, DSBs, DNA double-strand breaks, ATM, ataxia telangiectasia mutated, ATR, ATM-Rad3-related

We propose a mechanism, that induces rotation of a group of individuals by applying time delayed interaction between them. In experiments with micro-particles and laser nudging rotational phases, phase transitions and critical points are observed.

RNA polymerase II (Pol II)-dependent transcription in stimulus-inducible genes requires topoisomerase IIβ (TOP2B)-mediated DNA strand break and the activation of DNA damage response signaling in humans. Here, we report a novel function of the breast cancer 1 (BRCA1)-BRCA1 associated ring domain 1 (BARD1) complex, in this process. We found that BRCA1 is phosphorylated at S1524 by the kinases ATM and ATR during gene activation and that this event is essential for productive transcription. Our in vitro biochemical analyses showed TOP2B and BARD1 interaction and colocalization in the EGR1 transcription start site (TSS) and that the BRCA1-BARD1 complex ubiquitinates TOP2B, which appears to stabilize TOP2B protein in the cell and binding to DNA. Intriguingly, BRCA1 phosphorylation at S1524 controls this interaction. In addition, genomic analyses indicated colocalization between TOP2B and BRCA1 in a large number of protein-coding genes. Together, these findings reveal the novel function of the BRCA1-BARD1 complex in gene expression and in the regulation of TOP2B during Pol II transcription.Significance StatementMaintaining genomic integrity against cellular and extracellular genotoxic elements is essential for normal cell growth and function. Recent studies indicated that stimulus-induced transcription provokes topoisomerase IIβ-mediated DNA strand break and DNA damage response signaling, requiring DNA repair to be coupled with transcription. Here, we present a novel role for the BRCA1-BARD1 complex in regulating the transcription of serum-inducible genes and the stability of topoisomerase IIβ. The mechanism involving topoisomerase IIβ ubiquitination by the BRCA1-BARD1 complex and the phosphorylation of BRCA1 S1524 upon transcriptional activation appears to function as a switch to the reaction. Our findings provide the first evidence of functional interaction between the BRCA1-BARD1 complex and topoisomerase IIβ in transcription in humans.

Hematopoiesis, the complex developmental process that forms blood components and replenishes the blood system, involves multiple intracellular and extracellular mechanisms. We previously demonstrated that lysophosphatidic acid (LPA), a lipid growth factor, has opposing regulatory effects on erythrocyte differentiation through activation of LPA receptors 2 and 3; yet the mechanisms underlying this process remain unclear. In this study, LPA(2) is observed that highly expressed in common myeloid progenitors (CMP) in murine myeloid cells, whereas the expression of LPA(3) displaces in megakaryocyte-erythroid progenitors (MEP) of later stage of myeloid differentiation. Therefore, we hypothesized that the switching expression of LPA(2) and LPA(3) determine the hematic homeostasis of mammalian megakaryocytic-erythroid lineage. In vitro colony-forming unit assays of murine progenitors reveal that LPA(2) agonist GRI reduces the erythroblast differentiation potential of CMP. In contrast, LPA(3) agonist OMPT increases the production of erythrocytes from megakaryocyte-erythrocyte progenitor cells (MEP). In addition, treatment with GRI reduces the erythroid, CMP, and MEP populations in mice, indicating that LPA(2) predominantly inhibits myeloid differentiation at an early stage. In contrast, activation of LPA(3) increases the production of terminally differentiated erythroid cells through activation of erythropoietic transcriptional factor. We also demonstrate that the LPA(3) signaling is essential for restoration of phenylhydrazine (PHZ)-induced acute hemolytic anemia in mice and correlates to erythropoiesis impairment of Hutchinson-Gilford progeria Symptom (HGPS) premature aging expressed K562 model. Our results reveal the distinct roles of LPA(2) and LPA(3) at different stages of hematopoiesis in vivo, providing potentiated therapeutic strategies of anemia treatment.

Astronauts on interplanetary missions - such as to Mars - will be exposed to space radiation, a spectrum of highly-charged, fast-moving particles that includes 56Fe and 28Si. Earth-based preclinical studies show space radiation decreases rodent performance in low- and some high-level cognitive tasks. Given astronaut use of touchscreen platforms during training and space flight and given the ability of rodent touchscreen tasks to assess functional integrity of brain circuits and multiple cognitive domains in a non-aversive way, here we exposed 6-month-old C57BL/6J male mice to whole-body space radiation and subsequently assessed them on a touchscreen battery. Relative to Sham treatment, 56Fe irradiation did not overtly change performance on tasks of visual discrimination, reversal learning, rule-based, or object-spatial paired associates learning, suggesting preserved functional integrity of supporting brain circuits. Surprisingly, 56Fe irradiation improved performance on a dentate gyrus-reliant pattern separation task; irradiated mice learned faster and were more accurate than controls. Improved pattern separation performance did not appear to be touchscreen-, radiation particle-, or neurogenesis-dependent, as 56Fe and 28Si irradiation led to faster context discrimination in a non-touchscreen task and 56Fe decreased new dentate gyrus neurons relative to Sham. These data urge revisitation of the broadly-held view that space radiation is detrimental to cognition.

The DNA-dependent protein kinase (DNA-PK), consisting of the DNA binding Ku70/80 heterodimer and the catalytic subunit DNA-PKcs, has been well characterized in the non-homologous end-joining mechanism for DNA double strand break (DSB) repair and radiation resistance. Besides playing a role in DSB repair, DNA-PKcs is required for the cellular response to replication stress and participates in the ATR-Chk1 signaling pathway. However, the mechanism through which DNA-PKcs is recruited to stalled replication forks is still unclear. Here, we report that the apoptosis mediator p53-induced protein with a death domain (PIDD) is required to promote DNA-PKcs activity in response to replication stress. PIDD is known to interact with PCNA upon UV-induced replication stress. Our results demonstrate that PIDD is required to recruit DNA-PKcs to stalled replication forks through direct binding to DNA-PKcs at the N’ terminal region. Disruption of the interaction between DNA-PKcs and PIDD not only compromises the ATR association and regulation of DNA-PKcs, but also the ATR signaling pathway, intra-S-phase checkpoint and cellular resistance to replication stress. Taken together, our results indicate that PIDD, but not the Ku heterodimer, mediates the DNA-PKcs activity at stalled replication forks and facilitates the ATR signaling pathway in the cellular response to replication stress.

Background/Aims: Hyperglycemia has been shown to increase the incidence and metastasis in various types of cancers. However, the correlation between hyperglycemia and lymphatic metastasis in prostate cancer (PCa) remains unclear. Our previous study demonstrated that lysophosphatidic acid (LPA) enhances vascular endothelial growth factor-C (VEGF-C) expression, a lymphangiogenic factor, through activating it receptors LPA1/3 in prostate cancer (PCa) cells. Moreover, hyperglycemia up-regulates autotaxin (ATX) expression, a LPA-generating enzyme. Therefore, we propose that high glucose promotes VEGF-C expression through LPA signaling in PCa cells. Methods: Pharmacological inhibitors and siRNAs were utilized to investigate the molecular mechanism of high glucose-induced VEGF-C expression. Real-time PCR and Western blot were used to determine the mRNA and protein expressions, respectively. Cellular bioenergetics analysis was performed to determine the glycolysis levels. Results: We demonstrated that the expressions of VEGF-C, ATX, and calreticulin were increased upon high glucose treatments in PC-3 cells. Moreover, high glucose-induced VEGF-C expression was mediated through the LPA1/3, PLC, Akt, ROS and LEDGF-dependent pathways. Additionally, high glucose enhanced the aerobic glycolysis via LPA1/3. Conclusion: These results indicated that hyperglycemia leads to LPA synthesis, and subsequent promoting pathological consequence of PCa. These novel findings could potentially provide new strategies for PCa treatments.

LILRB4, also known as ILT3, is an immune inhibitory transmembrane protein found on monocytes and antigen presenting cells, including dendritic cells (DCs). LILRB4 upregulation in DCs induces a tolerogenic phenotype that facilitates the generation of antigen-specific T regulatory cells. LILRB4 is also expressed on acute myeloid leukemia (AML) with monocytic differentiation, in which it promotes T cell suppression and tumor infiltration. IO-202 is a first-in-class LILRB4 antagonist antibody that is being evaluated in a Phase I trial (NCT04372433) for the treatment of AML and chronic myelomonocytic leukemia (CMML). RNA-seq data from TCGA database indicates that LILRB4 expression is upregulated in many solid tumor types. Therefore, the therapeutic potential of IO-202 in solid tumors was investigated in this study. Using computational biology approaches, we found that high LILRB4 expression in solid tumors from TCGA database is associated with macrophage infiltration in the tumor microenvironment. Flow cytometric analysis of cancer patients' blood and tumor samples confirmed LILRB4 expression on tumor-associated macrophages (TAMs) and on monocytic myeloid-derived suppressor cells (M-MDSCs) and DCs in tumor and periphery. These data raised the hypothesis that LILRB4 functions as a myeloid checkpoint and contributes to tumor immune evasion, not only in AML, but also in many solid tumor types. LILRB4 is not present in rodents. As such, the functional activity and anti-tumor efficacy of IO-202 were evaluated using human primary immune cells and immunocompetent LILRB4 transgenic mice, respectively. In healthy donor monocyte-derived DCs, IO-202 treatment promoted DC maturation, activation and an antigen presenting phenotype, as well as enhanced their ability to activate allogeneic T cells. In the radiation therapy (RT)-resistant Lewis lung carcinoma (LLC) syngeneic model, IO-202 in combination with RT resulted in tumor growth inhibition, which was associated with changes in the relative abundance of tumor-infiltrating immune cells, evidenced by a reduction in M-MDSCs and an increase in T cells, along with increased T cell activation. In conclusion, our data suggest that LILRB4 functions as a myeloid checkpoint in multiple cancer types and that IO-202, the first-in-class LILRB4 antagonist antibody, enhances dendritic cell function and T cell activation in vitro and anti-tumor immunity in a solid tumor model in vivo. These data demonstrate the therapeutic potential of IO-202 as a myeloid checkpoint inhibitor for solid tumors. Citation Format: Maria José Costa, Tao Huang, Jing-Tyan Ma, Caroline Bonnans, Azita Tabrizi, Xiaoling C. Liao, Paul Woodard, Benjamin P. Chen, Ching-Cheng Hsu, Mi Deng, Cheng Cheng Zhang, An Song. IO-202, a first-in-class LILRB4 antagonist antibody, activates dendritic cells and inhibits solid tumor growth in preclinical studies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1629.

Repetitive DNA is prone to replication fork stalling, which can lead to genome instability. Here, we find that replication fork stalling at telomeres leads to the formation of t‐circle‐tails, a new extrachromosomal structure that consists of circular telomeric DNA with a single‐stranded tail. Structurally, the t‐circle‐tail resembles cyclized leading or lagging replication intermediates that are excised from the genome by topoisomerase II‐mediated cleavage. We also show that the DNA damage repair machinery NHEJ is required for the formation of t‐circle‐tails and for the resolution of stalled replication forks, suggesting that NHEJ, which is normally constitutively suppressed at telomeres, is activated in the context of replication stress. Inhibition of NHEJ or knockout of DNA‐PKcs impairs telomere replication, leading to multiple‐telomere sites (MTS) and telomere shortening. Collectively, our results support a “looping‐out” mechanism, in which the stalled replication fork is cut out and cyclized to form t‐circle‐tails, and broken DNA is religated. The telomere loss induced by replication stress may serve as a new factor that drives replicative senescence and cell aging.

Metabolic reprogramming by oncogenic signals promotes cancer initiation and progression. The oncogene KRAS and tumour suppressor STK11, which encodes the kinase LKB1, regulate metabolism and are frequently mutated in non-small-cell lung cancer (NSCLC). Concurrent occurrence of oncogenic KRAS and loss of LKB1 (KL) in cells specifies aggressive oncological behaviour. Here we show that human KL cells and tumours share metabolomic signatures of perturbed nitrogen handling. KL cells express the urea cycle enzyme carbamoyl phosphate synthetase-1 (CPS1), which produces carbamoyl phosphate in the mitochondria from ammonia and bicarbonate, initiating nitrogen disposal. Transcription of CPS1 is suppressed by LKB1 through AMPK, and CPS1 expression correlates inversely with LKB1 in human NSCLC. Silencing CPS1 in KL cells induces cell death and reduces tumour growth. Notably, cell death results from pyrimidine depletion rather than ammonia toxicity, as CPS1 enables an unconventional pathway of nitrogen flow from ammonia into pyrimidines. CPS1 loss reduces the pyrimidine to purine ratio, compromises S-phase progression and induces DNA-polymerase stalling and DNA damage. Exogenous pyrimidines reverse DNA damage and rescue growth. The data indicate that the KL oncological genotype imposes a metabolic vulnerability related to a dependence on a cross-compartmental pathway of pyrimidine metabolism in an aggressive subset of NSCLC.

Supplemental Digital Content is available in the text.

Hutchinson-Gilford progeria syndrome (HGPS) is a rare laminopathy that produces a mutant form of prelamin A, known as Progerin, resulting in premature aging. HGPS cells show morphological abnormalities of the nuclear membrane, reduced cell proliferation rates, accumulation of reactive oxygen species (ROS), and expression of senescence markers. Lysophosphatidic acid (LPA) is a growth factor-like lipid mediator that regulates various physiological functions via activating multiple LPA G protein-coupled receptors. Here, we study the roles of LPA and LPA receptors in premature aging. We report that the protein level of LPA3 was highly downregulated through internalization and the lysosomal degradation pathway in Progerin-transfected HEK293 cells. By treating Progerin HEK293 cells with an LPA3 agonist (OMPT, 1-Oleoyl-2-O-methyl-rac-glycerophosphothionate) and performing shRNA knockdown of the Lpa3r transcript in these cells, we showed that LPA3 activation increased expression levels of antioxidant enzymes, consequently inhibiting ROS accumulation and ameliorating cell senescence. LPA3 was shown to be downregulated in HGPS patient fibroblasts through the lysosomal pathway, and it was shown to be crucial for ameliorating ROS accumulation and cell senescence in fibroblasts. Moreover, in a zebrafish model, LPA3 deficiency was sufficient to cause premature aging phenotypes in multiple organs, as well as a shorter lifespan. Taken together, these findings identify the decline of LPA3 as a key contributor to the premature aging phenotypes of HGPS cells and zebrafish.

Vanillin is a natural compound endowed with antioxidant and anti-mutagenic properties. We previously identified the vanillin derivative VND3207 with strong radio-protective and antioxidant effects and found that VND3207 confers survival benefit and protection against radiation-induced intestinal injury (RIII) in mice. We also observed that VND3207 treatment enhanced the expression level of the catalytic subunit of the DNA-dependent protein kinase (DNA-PKcs) in human lymphoblastoid cells with or without γ-irradiation. DNA-PKcs is a critical component of DNA double strand break repair pathway and also regulates mitotic progression by stabilizing spindle formation and preventing mitotic catastrophe in response to DNA damage. In the present study, we found that VND3207 protected intestinal epithelial cells in vitro against ionizing radiation by promoting cell proliferation and inhibiting cell apoptosis. In addition, VND3207 promoted DNA-PKcs activity by increasing autophosphorylation at S2056 site. Consistent with this, VND3207 significantly decreased the number of γH2AX foci and mitotic catastrophe after radiation. DNA-PKcs deficiency abolished these VND3207 radio-protective effects, indicating that DNA-PKcs activation is essential for VND3207 activity. In conclusion, VND3207 promoted intestinal repair following radiation injury by regulating the DNA-PKcs pathway.

Astronauts on interplanetary space missions - such as to Mars - will be exposed to space radiation, a spectrum of highly-charged, fast-moving particles that includes 56Fe and 28Si. Earth-based preclinical studies with mature, “astronaut-aged” rodents show space radiation decreases performance in low- and some high-level cognitive tasks. Given the prevalence of touchscreens in astronaut training and in-mission assessment, and the ability of rodent touchscreen tasks to assess the functional integrity of brain circuits and multiple cognitive domains in a non-aversive way, it is surprising the effect of space radiation on rodent touchscreen performance is unknown. To fill this knowledge gap, 6-month-old C57BL/6J male mice were exposed to whole-body space radiation and assessed on a touchscreen battery starting 1-month later. Relative to Sham, 56Fe irradiation did not overtly change performance on tasks of visual discrimination, reversal learning, rule-based, or object-spatial paired associates learning, suggesting preserved functional integrity of supporting brain circuits. Surprisingly, 56Fe irradiation led to better performance on a dentate gyrus-reliant task of pattern separation ability. Irradiated mice discriminated similar visual cues in ∼40% fewer days and ∼40% more accurately than control mice. Improved pattern separation was not touchscreen-, radiation-particle, or neurogenesis-dependent, as both 56Fe and 28Si irradiation led to faster context discrimination (e.g. Sham Block 5 vs. 56Fe Block 2) in a non-touchscreen task and 56Fe led to fewer new dentate gyrus neurons relative to Sham. These data urge revisitation of the broadly-held view that space radiation is detrimental to cognition.SIGNIFICANCE STATEMENTAstronauts on an interplanetary mission - such as to Mars - will be unavoidably exposed to galactic cosmic radiation, a spectrum of highly-charged, fast-moving particles. Rodent studies suggest space radiation is detrimental to cognition. However, here we show this is not universally true. Mature mice that received whole body exposure to Mars-relevant space radiation perform similarly to control mice on high-level cognitive tasks, reflecting the functional integrity of key neural circuits. Even more surprisingly, irradiated mice perform better than controls in both appetitive and aversive tests of pattern separation, a mission-critical task reliant on dentate gyrus integrity. Notably, improved pattern separation was not touchscreen-, radiation-particle-, or neurogenesis-dependent. Our work urges revisitation of the generally-accepted conclusion that space radiation is detrimental to cognition.

The intestine is a highly radiosensitive tissue that is susceptible to structural and functional damage due to systemic as well as localized radiation exposure. Unfortunately, no effective prophylactic or therapeutic agents are available at present to manage radiation-induced intestinal injuries. We observed that the vanillin derivative VND3207 improved the survival of lethally irradiated mice by promoting intestinal regeneration and increasing the number of surviving crypts. Pre-treatment with VND3207 significantly increased the number of Lgr5+ intestinal stem cells (ISCs) and their daughter cells, the transient Ki67+ proliferating cells. Mechanistically, VND3207 decreased oxidative DNA damage and lipid peroxidation and maintained endogenous antioxidant status by increasing the level of superoxide dismutase and total antioxidant capacity. In addition, VND3207 maintained appropriate levels of activated p53 that triggered cell cycle arrest but were not sufficient to induce NOXA-mediated apoptosis, thus ensuring DNA damage repair in the irradiated small intestinal crypt cells. Furthermore, VND3207 treatment restores the intestinal bacterial flora structures altered by TBI exposure. In conclusion, VND3207 promoted intestinal repair following radiation injury by reducing reactive oxygen species-induced DNA damage and modulating appropriate levels of activated p53 in intestinal epithelial cells.

Hutchinson–Gilford progeria syndrome (HGPS) is a rare laminopathy that produces a mutant form of prelamin A, known as Progerin, resulting in premature aging. HGPS cells show morphological abnormalities of the nuclear membrane, reduced cell proliferation rates, accumulation of reactive oxygen species (ROS), and expression of senescence markers. Lysophosphatidic acid (LPA) is a growth factor‐like lipid mediator that regulates various physiological functions via activating multiple LPA G protein‐coupled receptors. Here, we study the roles of LPA and LPA receptors in premature aging. We report that the protein level of LPA3 was highly downregulated through internalization and the lysosomal degradation pathway in Progerin‐transfected HEK293 cells. By treating Progerin HEK293 cells with an LPA3 agonist (OMPT, 1‐Oleoyl‐2‐O‐methyl‐rac‐glycerophosphothionate) and performing shRNA knockdown of the Lpa3r transcript in these cells, we showed that LPA3 activation increased expression levels of antioxidant enzymes, consequently inhibiting ROS accumulation and ameliorating cell senescence. LPA3 was shown to be downregulated in HGPS patient fibroblasts through the lysosomal pathway, and it was shown to be crucial for ameliorating ROS accumulation and cell senescence in fibroblasts. Moreover, in a zebrafish model, LPA3 deficiency was sufficient to cause premature aging phenotypes in multiple organs, as well as a shorter lifespan. Taken together, these findings identify the decline of LPA3 as a key contributor to the premature aging phenotypes of HGPS cells and zebrafish., In normal cells, activation of LPA3 stabilizes Nrf2 and enhances antioxidants to prevent accumulation of reactive oxygen species (ROS) and cell senescence. In Hutchinson–Gilford progeria syndrome (HGPS) cells, LPA3 is shown to be downregulated through high internalization and subsequent lysosomal degradation. The decline of LPA3 contributes to ROS accumulation and cell senescence of HGPS cells.

In this paper, the effect of channel annealing and oxygen flow rate in