Ubiquitin C-terminal Hydrolase Research Articles

A novel organotypic cortical slice culture model for traumatic brain injury: molecular changes induced by injury and mesenchymal stromal cell secretome treatment.

Traumatic brain injury (TBI) is a major worldwide neurological disorder with no neuroprotective treatment available. Three-dimensional (3D) in vitro models of brain contusion serving as a screening platform for drug testing are lacking. Here we developed a new in vitro model of brain contusion on organotypic cortical brain slices and tested its responsiveness to mesenchymal stromal cell (MSC) derived secretome. A focal TBI was induced on organotypic slices by an electromagnetic impactor. Compared to control condition, a temporal increase in cell death was observed after TBI by propidium iodide incorporation and lactate dehydrogenase release assays up to 48 h post-injury. TBI induced gross neuronal loss in the lesion core, with disruption of neuronal arborizations measured by microtubule-associated protein-2 (MAP-2) immunostaining and associated with MAP-2 gene down-regulation. Neuronal damage was confirmed by increased levels of neurofilament light chain (NfL), microtubule associated protein (Tau) and ubiquitin C-terminal hydrolase L1 (UCH-L1) released into the culture medium 48 h after TBI. We detected glial activation with microglia cells acquiring an amoeboid shape with less ramified morphology in the contusion core. MSC-secretome treatment, delivered 1 h post-injury, reduced cell death in the contusion core, decreased NfL release in the culture media, promoted neuronal reorganization and improved microglia survival/activation. Our 3D in vitro model of brain contusion recapitulates key features of TBI pathology. We showed protective effects of MSC-secretome, suggesting the model stands as a tractable medium/high throughput, ethically viable, and pathomimetic biological asset for testing new cell-based therapies.

Potential diagnostic value of CSF metabolism-related proteins across the Alzheimer’s disease continuum

BackgroundAlzheimer’s disease (AD) cerebrospinal fluid (CSF) core biomarkers (Aβ42/40 ratio, p-tau, and t-tau) provide high diagnostic accuracy, even at the earliest stage of disease. However, these markers do not fully reflect the complex AD pathophysiology. Recent large scale CSF proteomic studies revealed several new AD candidate biomarkers related to metabolic pathways. In this study we measured the CSF levels of four metabolism-related proteins not directly linked to amyloid- and tau-pathways (i.e., pyruvate kinase, PKM; aldolase, ALDO; ubiquitin C-terminal hydrolase L1, UCHL1, and fatty acid-binding protein 3, FABP3) across the AD continuum. We aimed at validating the potential value of these proteins as new CSF biomarkers for AD and their possible involvement in AD pathogenesis, with specific interest on the preclinical phase of the disease.MethodsCSF PKM and ALDO activities were measured with specific enzyme assays while UCHL1 and FABP3 levels were measured with immunoassays in a cohort of patients composed as follows: preclinical AD (pre-AD, n = 19, cognitively unimpaired), mild cognitive impairment due to AD (MCI-AD, n = 50), dementia due to AD (ADdem, n = 45), and patients with frontotemporal dementia (FTD, n = 37). Individuals with MCI not due to AD (MCI, n = 30) and subjective cognitive decline (SCD, n = 52) with negative CSF AD-profile, were enrolled as control groups.ResultsCSF UCHL1 and FABP3 levels, and PKM activity were significantly increased in AD patients, already at the pre-clinical stage. CSF PKM activity was also increased in FTD patients compared with control groups, being similar between AD and FTD patients. No difference was found in ALDO activity among the groups.UCHL1 showed good performance in discriminating early AD patients (pre-AD and MCI-AD) from controls (AUC ~ 0.83), as assessed by ROC analysis. Similar results were obtained for FABP3. Conversely, PKM provided the best performance when comparing FTD vs. MCI (AUC = 0.80). Combination of PKM, FABP3, and UCHL1 improved the diagnostic accuracy for the detection of patients within the AD continuum when compared with single biomarkers.ConclusionsOur study confirmed the potential role of UCHL1 and FABP3 as neurodegenerative biomarkers for AD. Furthermore, our results validated the increase of PKM activity in CSF of AD patients, already at the preclinical phase of the disease. Increased PKM activity was observed also in FTD patients, possibly underlining similar alterations in energy metabolism in AD and FTD.

Increased expression of ubiquitin C-terminal hydrolase L1 in astrocytomas of ascending grades.

The ubiquitin-proteasome pathway controls the monitoring and degradation of important proteins and is involved in several cellular processes, such as development, differentiation, and transcriptional regulation. Recent evidence has shown that ubiquitin carboxy-terminal hydrolase-L1 (UCH-L1), a member of the deubiquitinating enzyme family that removes ubiquitin from protein substrates, is overexpressed in many types of cancer. This study thus examined the expression of UCH-L1 in human astrocytoma tissues. Formalin-fixed, paraffin-embedded astrocytoma samples were obtained from 40 patients, after which histopathological examination, typing, and grading were performed. The study group included 10 histologically normal brain tissues, which served as the control group, and 10 WHO grade II, 10 WHO grade III, and 10 WHO grade IV (glioblastoma) samples. Normal brain tissue samples were obtained from the histologically normal, non-tumoral portion of the pathology specimens. UCH-L1 expression was evaluated using quantitative reverse transcription-polymerase chain reaction and immunohistochemistry. Astrocytoma tissues exhibited higher UCH-L1 expression compared to the control group. UCH-L1 overexpression increased significantly together with the increase in astrocytoma grades (from II to IV). UCH-L1 could be a good diagnostic and therapeutic marker for determining astrocytoma development and progression.

Head Kinematics, Blood Biomarkers, and Histology in Large Animal Models of Traumatic Brain Injury and Hemorrhagic Shock.

Traumatic brain injury (TBI) and severe blood loss resulting in hemorrhagic shock (HS) are each leading causes of mortality and morbidity worldwide, and present additional treatment considerations when they are comorbid (TBI+HS) as a result of competing pathophysiological responses. The current study rigorously quantified injury biomechanics with high precision sensors and examined whether blood-based surrogate markers were altered in general trauma as well as post-neurotrauma. Eighty-nine sexually mature male and female Yucatan swine were subjected to a closed-head TBI+HS (40% of circulating blood volume; n = 68), HS only (n = 9), or sham trauma (n = 12). Markers of systemic (e.g., glucose, lactate) and neural functioning were obtained at baseline, and at 35 and 295 min post-trauma. Opposite and approximately twofold differences existed for both magnitude (device > head) and duration (head > device) of quantified injury biomechanics. Circulating levels of neurofilament light chain (NfL), glial fibrillary acidic protein (GFAP), and ubiquitin C-terminal hydrolase L1 (UCH-L1) demonstrated differential sensitivity for both general trauma (HS) and neurotrauma (TBI+HS) relative to shams in a temporally dynamic fashion. GFAP and NfL were both strongly associated with changes in systemic markers during general trauma and exhibited consistent time-dependent changes in individual sham animals. Finally, circulating GFAP was associated with histopathological markers of diffuse axonal injury and blood-brain barrier breach, as well as variations in device kinematics following TBI+HS. Current findings therefore highlight the need to directly quantify injury biomechanics with head mounted sensors and suggest that GFAP, NfL, and UCH-L1 are sensitive to multiple forms of trauma rather than having a single pathological indication (e.g., GFAP = astrogliosis).

Inflammation biomarkers IL‑6 and IL‑10 may improve the diagnostic and prognostic accuracy of currently authorized traumatic brain injury tools.

Traumatic brain injury (TBI) is currently one of the leading causes of mortality and disability worldwide. At present, no reliable inflammatory or specific molecular neurobiomarker exists in any of the standard models proposed for TBI classification or prognostication. Therefore, the present study was designed to assess the value of a group of inflammatory mediators for evaluating acute TBI, in combination with clinical, laboratory and radiological indices and prognostic clinical scales. In the present single-centre, prospective observational study, 109 adult patients with TBI, 20 adult healthy controls and a pilot group of 17 paediatric patients with TBI from a Neurosurgical Department and two intensive care units of University General Hospital of Heraklion, Greece were recruited. Blood measurements using the ELISA method, of cytokines IL-6, IL-8 and IL-10, ubiquitin C-terminal hydrolase L1 (UCH-L1) and glial fibrillary acidic protein, were performed. Compared with those in healthy control individuals, elevated IL-6 and IL-10 but reduced levels of IL-8 were found on day 1 in adult patients with TBI. In terms of TBI severity classifications, higher levels of IL-6 (P=0.001) and IL-10 (P=0.009) on day 1 in the adult group were found to be associated with more severe TBI according to widely used clinical and functional scales. Moreover, elevated IL-6 and IL-10 in adults were found to be associated with more serious brain imaging findings (rs<0.442; P<0.007). Subsequent multivariate logistic regression analysis in adults revealed that early-measured (day 1) IL-6 [odds ratio (OR)=0.987; P=0.025] and UCH-L1 (OR=0.993; P=0.032) are significant independent predictors of an unfavourable outcome. In conclusion, results from the present study suggest that inflammatory molecular biomarkers may prove to be valuable diagnostic and prognostic tools for TBI.

Fetal Ovarian Reserve: the Dynamic Changes in Ubiquitin C-Terminal Hydrolase L1.

The regulation of protein turnover by the unique deubiquitinating enzyme ubiquitin C-terminal hydrolase L1 (UCHL1) is only seen in oocytes, spermatogonia, and neurons. Our objective was to investigate variation in expression of UCHL1 across fetal maturation of oocytes that result in lifelong ovarian reserve. We performed a retrospective cohort study of 25 fetal autopsy specimens from 21 to 36weeks. This was an IRB-approved protocol with parental permission for use of tissues for research purposes. Tissues were stained for expression of the oocyte-specific protein UCHL1, and expression levels were evaluated using quantitative immunofluorescence across gestational ages after correction for the area and background absorbance. Corrected total cell fluorescence (CTCF) for expression of UCHL1 within human oocytes was compared across fetal gestational ages and oocyte size. Trends were analyzed using a locally weighted scatterplot smoothing algorithm. Local expression of UCHL1 increases in oocytes across ovarian development reaching a plateau at 27weeks with the maintenance of elevated levels through 36weeks gestational age. This maturation trend is also evidenced by the increase in protein expression as oocyte area increases (r = 0.5530, p ≤ 0.001) with the largest rise occurring as oocytes are enveloped into primordial follicles. The increase in expression as oocytes transition from oogonia into oocytes in primordial follicles and beyond may be part of the preparation of both oocytes and the surrounding somatic cells for the long-term maintenance of the ovarian reserve.

Evaluating Targeted Therapeutic Response With Predictive Blood-Based Biomarkers in Patients With Chronic Mild Traumatic Brain Injury.

Chronic consequences of mild traumatic brain injury (mTBI) are heterogeneous, but may be treatable with targeted medical and rehabilitation interventions. A biological signature for the likelihood of response to therapy (i.e., "predictive" biomarkers) would empower personalized medicine post-mTBI. The purpose of this study was to correlate pre-intervention blood biomarker levels and the likelihood of response to targeted interventions for patients with chronic issues attributable to mTBI. Patients with chronic symptoms and/or disorders secondary to mTBI >3 months previous (104 days to 15 years; n = 74) were enrolled. Participants completed pre-intervention assessments of symptom burden, comprehensive clinical evaluation, and blood-based biomarker measurements. Multi-domain targeted interventions for specific symptoms and impairments across a 6-month treatment period were prescribed. Participants completed a follow-up testing after the treatment period. An all-possible model's backward logistic regression was built to identify predictors of improvement in relation to blood biomarker levels before intervention. The minimum clinically important difference (MCID) of the change score (post-intervention subtracted from pre-intervention) for the Post-Concussion Symptom Scale (PCSS) to identify treatment responders from non-responders was the primary outcome. The MCID for total PCSS score was 10. The model to predict change in PCSS score over the 6-month intervention was significant (R2 = 0.09; p = 0.01) and identified ubiquitin C-terminal hydrolase L1 (odds ratio [OR] = 2.53; 95% confidence interval [CI], 1.18-5.46; p = 0.02) and hyperphosphorylated tau (p-tau; OR = 0.70; 95% CI, 0.51-0.96; p = 0.03) as significant predictors of symptom improvement beyond the PCSS MCID. In this cohort of chronic TBI subjects, blood biomarkers before rehabilitation intervention predicted the likelihood of response to targeted therapy for chronic disorders post-TBI.

Osteopontin depletion in macrophages perturbs proteostasis via regulating UCHL1-UPS axis and mitochondria-mediated apoptosis.

Osteopontin (OPN; also known as SPP1), an immunomodulatory cytokine highly expressed in bone marrow-derived macrophages (BMMΦ), is known to regulate diverse cellular and molecular immune responses. We previously revealed that glatiramer acetate (GA) stimulation of BMMΦ upregulates OPN expression, promoting an anti-inflammatory, pro-healing phenotype, whereas OPN inhibition triggers a pro-inflammatory phenotype. However, the precise role of OPN in macrophage activation state is unknown. Here, we applied global proteome profiling via mass spectrometry (MS) analysis to gain a mechanistic understanding of OPN suppression versus induction in primary macrophage cultures. We analyzed protein networks and immune-related functional pathways in BMMΦ either with OPN knockout (OPNKO) or GA-mediated OPN induction compared with wild type (WT) macrophages. The most significant differentially expressed proteins (DEPs) were validated using immunocytochemistry, western blot, and immunoprecipitation assays. We identified 631 DEPs in OPNKO or GA-stimulated macrophages as compared to WT macrophages. The two topmost downregulated DEPs in OPNKO macrophages were ubiquitin C-terminal hydrolase L1 (UCHL1), a crucial component of the ubiquitin-proteasome system (UPS), and the anti-inflammatory Heme oxygenase 1 (HMOX-1), whereas GA stimulation upregulated their expression. We found that UCHL1, previously described as a neuron-specific protein, is expressed by BMMΦ and its regulation in macrophages was OPN-dependent. Moreover, UCHL1 interacted with OPN in a protein complex. The effects of GA activation on inducing UCHL1 and anti-inflammatory macrophage profiles were mediated by OPN. Functional pathway analyses revealed two inversely regulated pathways in OPN-deficient macrophages: activated oxidative stress and lysosome-mitochondria-mediated apoptosis (e.g., ROS, Lamp1-2, ATP-synthase subunits, cathepsins, and cytochrome C and B subunits) and inhibited translation and proteolytic pathways (e.g., 60S and 40S ribosomal subunits and UPS proteins). In agreement with the proteome-bioinformatics data, western blot and immunocytochemical analyses revealed that OPN deficiency perturbs protein homeostasis in macrophages-inhibiting translation and protein turnover and inducing apoptosis-whereas OPN induction by GA restores cellular proteostasis. Taken together, OPN is essential for macrophage homeostatic balance via the regulation of protein synthesis, UCHL1-UPS axis, and mitochondria-mediated apoptotic processes, indicating its potential application in immune-based therapies.

Serum neurofilament light chain levels at attack predict post-attack disability worsening and are mitigated by inebilizumab: analysis of four potential biomarkers in neuromyelitis optica spectrum disorder

ObjectiveTo investigate relationships between serum neurofilament light chain (sNfL), ubiquitin C-terminal hydrolase L1 (sUCHL1), tau (sTau) and glial fibrillary acidic protein (sGFAP) levels and disease activity/disability in neuromyelitis optica spectrum...

Ficus deltoidea Leaf Alters Oxidative Stress, Protein Homeostasis and Ubiquitin-Proteasome Pathways in Fatty Acid-Induced Cell Line.

Ficus deltoidea (mistletoe fig) is a shrub well known among locals in Malaysia primarily for its treatment of toothaches, colds and wounds. The aim of this study is to determine the potential of leaves, sourced from three different varieties of F. deltoidea, to exhibit antioxidant activity, a reduction of lipid concentration, and protein expression in steatosis-induced liver cell lines. The leaves of three F. deltoidea varieties, namely Ficus deltoidea var. angustifolia, Ficus deltoidea var. trengganuensis and Ficus deltoidea var. kunstleri, were subjected to water extraction. The resulting crude extracts were fractionated using water and ethyl acetate. Palmitic acid was used to induce lipid accumulation (steatosis) in human liver (WRL68) cells, before all the samples were tested for their lipid-reducing activity. Several proteomic approaches were incorporated. The changes in protein expression were determined using 2-dimensional gel electrophoresis separation, whereas identification of our protein spots of interest was carried out via matrix-assisted laser desorption/ionization time-of-flight. Ficus deltoidea var. kunstleri alone demonstrated the ability to reduce lipids at the highest tested concentration (200 µg/mL) and was, therefore, used for subsequent experiments. Treatment with Ficus deltoidea var. kunstleri was found to restore redox status by increasing superoxide dismutase and glutathione peroxidase amounts and decreasing malondialdehyde formation. Six proteins were successfully identified; these were heat shock protein beta-1 (HSPB1), proteasome subunit alpha type 1 (PSMA1), glutathione S-transferase omega 1 (GSTO1), peroxiredoxin-1 (PRDX1), histone H2B (HIST1H2BD) and ubiquitin c-terminal hydrolase L3 (UCHL3). Through bioinformatics analysis, it was found that these proteins were significantly involved in specific pathways such as oxidative stress (PRDX1 and GSTO1), protein homeostasis (HSPB1) and degradation (UCHL3 and PSMA1). F. deltoidea pretreatment was shown to reduce lipid accumulation, thus improving the redox status and protein homeostasis. This suggests the role of F. deltoidea as a preventive mechanism in non-alcohol fatty liver disease.

Ubiquitin C-terminal hydrolase L1 after out-of-hospital cardiac arrest.

We studied the prognostic ability of serum ubiquitin C-terminal hydrolase L1 (UCH-L1) after out-of-hospital cardiac arrest (OHCA), compared to that of neuron-specific enolase (NSE). In this post-hoc analysis of the FINNRESUSCI study, we measured serum concentrations of UCH-L1 in 249 OHCA patients treated in 21 Finnish intensive care units in 2010-2011. We evaluated the ability of UCH-L1 to predict unfavourable outcome at 12 months (defined as cerebral performance category 3-5) by assessing the area under the receiver operating characteristic curve (AUROC), in comparison with NSE. The concentrations of UCH-L1 were higher in patients with unfavourable outcome than for those with favourable outcome: median concentration 10.8 ng/mL (interquartile range, 7.5-18.5 ng/mL) versus 7.8 ng/mL (5.9-11.8 ng/mL) at 24 h (p < .001), and 16.2 ng/mL (12.2-27.7 ng/mL) versus 11.5 ng/mL (9.0-17.2 ng/mL) (p < .001) at 48 h after OHCA. For UCH-L1 as a 12-month outcome predictor, the AUROC was 0.66 (95% confidence interval, 0.60-0.73) at 24 h and 0.66 (0.59-0.74) at 48 h. For NSE, the AUROC was 0.66 (0.59-0.73) at 24 h and 0.72 (0.65-0.80) at 48 h. The prognostic ability of UCH-L1 was not different from that of NSE at 24 h (p = .82) and at 48 h (p = .23). Concentrations of UCH-L1 in serum were higher in patients with unfavourable outcome than in those with favourable outcome. However, the ability of UCH-L1 to predict unfavourable outcome after OHCA was only moderate and not superior to that of NSE.

Rice tapetum differentiation is sensitive to downregulation of OsUCH3, a ubiquitin C-terminal hydrolase.

The tapetum is a special tissue within the stamen that supplies nutrients to support microspore differentiation. Many genes have been identified to function in tapetum differentiation (Astrand et al., 2021). Ubiquitin C-terminal hydrolase (UCH) is a type of cysteine protease involved in protein deubiquitination process (Mevissen and Komander, 2017) and plays roles in gonadal transformation and spermatogenesis in animals (Luo et al., 2009; Kwon et al,. 2004; Wang et al., 2006). OsUCH3 (Os02g43760) was highly expressed in early rice stamen cells (Chen et al., 2015), the OsUCH3 expression was first observed in all cells of anther primordium and then gradually concentrated into the germ cells and tapetum cells, and OsUCH3 protein exhibits stronger ubiquitin C-terminal hydrolase enzymatic activity (Wang et al., 2018). These data suggested that OsUCH3 is likely associated with stamen development. To explore whether OsUCH3 plays roles in rice stamen development, we constructed transgenic lines to down-regulate OsUCH3 expression through RNAi vector as described previously with primers (ccACTAGTATGGAGGATGCTCATTCC and TcGGATCCCACAACTTTCGAAAGAGC) (Liu et al., 2005) (Figure 1a–g) and the OsUCH3-targeting CRISPR-Cas9 mutant lines (Figure 1h). CRISPR-Cas9 osuch3 mutant lines exhibited the same male-sterile phenotype as OsUCH3R. In observation of the overall morphology, there was no significant difference at vegetable development (Figure 1a). However, low seed setting rate was observed in the RNAi lines (Figure 1b) and CRISPR-Cas9 osuch3 mutant (Figure 1h). Alexander staining showed that OsUCH3R lines had abnormal pollen (Figure 1d) with the latter being indicated by the significant reduction in pollen grain number (Figure 1e, g). The RT-qPCR results revealed that OsUCH3 expression levels were significantly reduced in OsUCH3R transgenic rice (Figure 1f). To examine whether OsUCH3 affected stamen development, we pollinated OsUCH3R pistils with wild-type pollen grains, which rescued the sterility of OsUCH3R. The result suggested that the low seed setting rate resulted mainly from down-expression of OsUCH3 (Figure 1i). Morphological analysis revealed abnormal tapetum differentiation and locule collapse were observed in the OsUCH3R lines from stage 5 (S5) through 12 (S12) (Figure 1j). This observation suggested that the downregulation of OsUCH3 caused a defect in the tapetum differentiation and stamen development. In contrast to the degeneration of the tapetum that was observed in the WT from stages 7 (S7) to 9 (S9) (Figure 1k–m), the tapetum in the OsUCH3R lines was not properly degenerated during these stages (Figure 1n–p) as revealed by transmission electron microscopy (TEM) analysis. In addition, TEM observations revealed that the secondary cell walls of the endothecium cells were thinner in the OsUCH3R lines than in the wild type (Figure 1p, red arrowhead). We found green fluorescence in wild-type tapetal cells from stages 7 to 9 (Figure 1q-t) using the terminal deoxynucleotidyl transferase-mediated TdT-mediated dUTP Nick-End Labeling (TUNEL) assay (Chen et al., 2018). No such TUNEL signals were detected in OsUCH3R tapetal cells during the same developmental period (Figure 1u–x). These results suggested that DNA degradation during tapetum differentiation after stage 7 was abnormal in OsUCH3R. Numerous genes were known being involved in tapetum differentiation (Chen et al., 2018). GAMYB4 was up-regulated while the expression of YY1, OsCP1 and UDT1 exhibited no change in the OsUCH3R lines (Figure 1y). OsUCH3 is lower expressed in shoot tips and leaf primordia. While no differential expression of SAM genes OsWOX3, the expression of OSH1 and OsWUS was significantly decreased in the OsUCH3R lines (Figure 1y). These changes demonstrated the link between abnormal tapetum differentiation in the OsUCH3R lines with the changes in the expression levels of known tapetum genes. The phenotypes we found in OsUCH3R lines and CRISPR mutants demonstrated that tapetal differentiation is sensitive to the change of expression level of OsUCH3 and protein deubiquitination is an importance factor for proper tapetum differentiation. This finding provided a new opportunity not only in deciphering the regulatory network of tapetum differentiation at protein level, but in manipulating male sterility for agricultural applications. Sequence data from this article can be found in the GenBank/EMBL data library. This work was supported by grants from the Chinese Transgenic Project (grant no. CARS-01-06, 2016ZX08010001 and 2016ZX08009-003) and the National Natural Science Foundation of China (grant no. 31630006). The authors declare no competing interests. D.H.W., Z.H.X. and S.N.B. designed the research and wrote the manuscript. D.H.W. performed most of the experiments. N.L. and S.D.Y. provided an assistance for mutant genotyping and plant material fixation. Z.S.C and Y.N.L provided technical assistance for transgenic plant analyse. Z.H.L helped the semithin sectioning.

Non-functional ubiquitin C-terminal hydrolase L1 drives podocyte injury through impairing proteasomes in autoimmune glomerulonephritis

Little is known about the mechanistic significance of the ubiquitin proteasome system (UPS) in a kidney autoimmune environment. In membranous nephropathy (MN), autoantibodies target podocytes of the glomerular filter resulting in proteinuria. Converging biochemical, structural, mouse pathomechanistic, and clinical information we report that the deubiquitinase Ubiquitin C-terminal hydrolase L1 (UCH-L1) is induced by oxidative stress in podocytes and is directly involved in proteasome substrate accumulation. Mechanistically, this toxic gain-of-function is mediated by non-functional UCH-L1, which interacts with and thereby impairs proteasomes. In experimental MN, UCH-L1 becomes non-functional and MN patients with poor outcome exhibit autoantibodies with preferential reactivity to non-functional UCH-L1. Podocyte-specific deletion of UCH-L1 protects from experimental MN, whereas overexpression of non-functional UCH-L1 impairs podocyte proteostasis and drives injury in mice. In conclusion, the UPS is pathomechanistically linked to podocyte disease by aberrant proteasomal interactions of non-functional UCH-L1.

Blood component resuscitative strategies to mitigate endotheliopathy in a murine hemorrhagic shock model.

Resuscitation with plasma components has been shown to improve endotheliopathy induced by hemorrhagic shock, but the optimal resuscitation strategy to preserve the endothelial glycocalyx has yet to be defined. The aim of this study was to determine if resuscitation with lactated Ringer's (LR), whole blood (WB), packed red blood cells (RBCs), platelet-rich plasma (PRP), platelet poor plasma, balanced RBC:PRP (1:1), or day 14 (d14) RBC would best minimize endothelial damage following shock. Male C57BL/6 mice were hemorrhaged to a goal mean arterial pressure of 25 mm Hg for 1 hour. Unshocked sham mice served as controls. Mice were then resuscitated with equal volumes of LR, WB, RBC, PRP, platelet poor plasma, 1:1, or d14 RBC and then sacrificed at 1, 4, or 24 hours (n = 5). Serum was analyzed for syndecan-1, ubiquitin C-terminal hydrolase L1, and cytokine concentrations. Lungs underwent syndecan-1 immunostaining, and lung injury scores were calculated after hematoxylin and eosin. Proteolytic cleavage of the endothelial glycocalyx was assessed by serum matrix metalloprotease 9 levels. Serum syndecan-1 and ubiquitin C-terminal hydrolase L1 levels were significantly increased following resuscitation with d14 RBC compared with other groups. Early elevation in lung syndecan-1 staining was noted in LR-treated mice, while d14 mice showed decreased staining compared with sham mice following shock. Lung injury scores were significantly elevated 4 hours after resuscitation with LR and d14 RBC compared with WB. Serum matrix metalloprotease 9 levels were significantly increased at 1 and 4 hours in d14 mice compared with sham mice. Systemic inflammation was increased in animals receiving LR, 1:1, or d14 RBC. Resuscitation with WB following hemorrhagic shock reduces endothelial syndecan-1 shedding and mitigates lung injury. Aged RBC and LR fail to attenuate endothelial injury following hemorrhagic shock. Further research will be necessary to determine the effect of each of these resuscitative fluids in a hemorrhagic shock model with the addition of tissue injury.

Abstract 2212: Prevalence of PGP9.5 expression in human cancers: A TMA study of 14,900 tumors from 148 tumor types

Abstract The ubiquitin C-terminal hydrolase L1 (UCH-L1), also termed protein gene product 9.5 (PGP9.5) is an important component of the ubiquitination/deubiquitination system and plays a role in the posttranslational modification of proteins including protein degradation, relocation and change of function. Altered PGP9.5 expression has been suggested to play a role for resistance to chemotherapy, metastasis, and patient prognosis in several tumor entities. To comprehensively determine PGP9.5 expression in normal and neoplastic tissues, a tissue microarray containing 14,913 samples from 148 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. PGP9.5 immunostaining was found in 2,667 of 11,062 analyzed tumors and considered weak in 9.8%, moderate in 5.8% and strong in 8.5% of tumors. 113 of 148 tumor categories showed at least one positive case, and 90 of these tumor categories contained at least one case with strong PGP9.5 staining. PGP9.5 positivity was most seen in various types of neuronal and neuroendocrine neoplasms (71.1-100%), germ cell neoplasms of the testis (82.1%), and in mesotheliomas (74%). PGP9 positivity was seen in 14.2% of 606 clear cell and in 45.4% of 255 papillary renal cell carcinomas (RCC). In clear cell RCC, strong PGP9.5 staining was associated with high ISUP grade (p&amp;lt;0.0001), pT stage (p=0.0012), nodal (p=0.038) and distant metastasis (p&amp;lt;0.0001) as well as with a shortened overall, tumor specific and recurrence free survival (p&amp;lt;0.0001 each). In papillary RCC, strong PGP9.5 staining was significantly associated with high ISUP grade (p=0.009), advanced UICC stage (p=0.015), and shortened recurrence free survival (p&amp;lt;0.0001). In urothelial carcinoma of the urinary bladder, high PGP9.5 expression was associated with muscle-invasion (p&amp;lt;0.0001) but PGP9.5 immunostaining was unrelated to prognosis in pT2-4 carcinomas. In a joint analysis of 527 squamous cell carcinomas from 11 different sites of origin, PGP9.5 positivity was associated with high tumor grade (p=0.0021). PGP9.5 immunostaining was unrelated to pT and pN status in 207 serous high-grade and 82 endometrioid ovarian carcinoma, in 221 endometrioid endometrium cancer as well as in 292 papillary and in 89 follicular thyroid carcinomas. In ductal adenocarcinomas of the pancreas and in 356 gastric adenocarcinomas, PGP9.5 staining was unrelated to grade, pT and pN stage. Our data provide an overview on prevalence of PGP9.5 expression in cancer. PGP9.5 expression occurs commonly in many different tumor entities. PGP9.5 overexpression is strikingly linked to patient outcome in some tumor entities (i.e. clear cell RCC) but appears to be unrelated to unfavorable tumor characteristics in various other important tumor entities (i.e. gastric, pancreatic, ovarian cancer). Citation Format: Sekander Scherzai, Maximilian Lennartz, Frank Jacobsen, Florian Viehweger, David Dum, Anne Menz, Ria Uhlig, Andrea Hinsch, Doris Hoeflmayer, Christoph Fraune, Christian Bernreuther, Patrick Lebok, Soeren Weidemann, Guido Sauter, Till Sebastian Clauditz, Till Krech, Andreas H Marx, Ronald Simon, Stefan Steurer, Eike Burandt, Natalia Gorbokon, Sarah Minner. Prevalence of PGP9.5 expression in human cancers: A TMA study of 14,900 tumors from 148 tumor types [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2212.

Evaluation of plasma levels of NFL, GFAP, UCHL1 and tau as Parkinson's disease biomarkers using multiplexed single molecule counting

Objective biomarkers for Parkinson’s Disease (PD) could aid early and specific diagnosis, effective monitoring of disease progression, and improved design and interpretation of clinical trials. Although alpha-synuclein remains a biomarker candidate of interest, the multifactorial and heterogenous nature of PD highlights the need for a PD biomarker panel. Ideal biomarker candidates include markers that are detectable in easily accessible samples, (ideally blood) and that reflect the underlying pathological process of PD. In the present study, we explored the diagnostic and prognostic PD biomarker potential of the SIMOA neurology 4-plex-A biomarker panel, which included neurofilament light (NFL), glial fibrillary acid protein (GFAP), tau and ubiquitin C-terminal hydrolase L1 (UCHL-1). We initially performed a serum vs plasma comparative study to determine the most suitable blood-based matrix for the measurement of these proteins in a multiplexed assay. The levels of NFL and GFAP in plasma and serum were highly correlated (Spearman rho-0.923, p < 0.0001 and rho = 0.825, p < 0.001 respectively). In contrast, the levels of tau were significantly higher in plasma compared to serum samples (p < 0.0001) with no correlation between sample type (Spearman p > 0.05). The neurology 4-plex-A panel, along with plasma alpha-synuclein was then assessed in a cross-sectional cohort of 29 PD patients and 30 controls. Plasma NFL levels positively correlated with both GFAP and alpha-synuclein levels (rho = 0.721, p < 0.0001 and rho = 0.390, p < 0.05 respectively). As diagnostic biomarkers, the control and PD groups did not differ in their mean NFL, GFAP, tau or UCHL-1 plasma levels (t test p > 0.05). As disease state biomarkers, motor severity (MDS-UPDRS III) correlated with increased NFL (rho = 0.646, p < 0.0001), GFAP (rho = 0.450, p < 0.05) and alpha-synuclein levels (rho = 0.406, p < 0.05), while motor stage (Hoehn and Yahr) correlated with increased NFL (rho = 0.455, p < 0.05) and GFAP (rho = 0.549, p < 0.01) but not alpha-synuclein levels (p > 0.05). In conclusion, plasma was determined to be most suitable blood-based matrix for multiplexing the neurology 4-plex-A panel. Given their correlation with motor features of PD, NFL and GFAP appear to be promising disease state biomarker candidates and further longitudinal validation of these two proteins as blood-based biomarkers for PD progression is warranted.

Prehospital Electroencephalography to Detect Traumatic Brain Injury during Helicopter Transport: A Pilot Observational Cohort Study

Objective Early recognition of traumatic brain injury (TBI) is important to facilitate time-sensitive care. Electroencephalography (EEG) can identify TBI, but feasibility of EEG has not been evaluated in prehospital settings. We tested the feasibility of obtaining single-channel EEG during air medical transport after trauma. We measured association between quantitative EEG features, early blood biomarkers, and abnormalities on head computerized tomography (CT). Methods We performed a pilot prospective, observational study enrolling consecutive patients transported by critical care air ambulance from the scene of trauma to a Level I trauma center. During transport, prehospital clinicians placed a sensor on the patient’s forehead to record EEG. We reviewed EEG waveforms and selected 90 seconds of recording for quantitative analysis. EEG data processing included fast Fourier transform to summarize component frequency power in the delta (0-4 Hz), theta (4-8 Hz), and alpha (8-13 Hz) ranges. We collected blood samples on day 1 and day 3 post-injury and measured plasma levels of two brain injury biomarkers (ubiquitin C-terminal hydrolase L1 [UCH-L1] and glial fibrillary acidic protein [GFAP]). We compared predictors between individuals with and without CT-positive TBI findings. Results Forty subjects were enrolled, with EEG recordings successfully obtained in 34 (85%). Reasons for failure included uncharged battery (n = 5) and user error (n = 1). Data were lost in three cases. Of 31 subjects with data, interpretable EEG signal was recorded in 26 (84%). Mean age was 48 (SD 16) years, 79% were male, and 50% suffered motor vehicle crashes. Eight subjects (24%) had CT-positive TBI. Subjects with and without CT-positive TBI had similar median delta power, alpha power, and theta power. UCH-L1 and GFAP plasma levels did not differ across groups. Delta power inversely correlated with UCH-L1 day 1 plasma concentration (r = -0.60, p = 0.03). Conclusions Prehospital EEG acquisition is feasible during air transport after trauma.

Ubiquitin C-terminal hydrolase 1 is increased in migraine attack.

This study aimed to determine the serum level of Ubiquitin C-terminal hydrolase 1 enzyme during a migraine attack and after its treatment. Blood samples of 43 patients and 30 healthy controls who presented to the emergency department with migraine attacks were analysed. Study sample was classified into three groups: Group 1 (patients presenting with migraine attack), Group 2 (4thhour after dexketoprofen treatment) and Group 3 (healthy control). Demographic data of patients, visual analogue scale and Ubiquitin C-terminal hydrolase 1 levels were analysed. Median (IQR) Ubiquitin C-terminal hydrolase 1 levels were 13.70 (10.75-18.92) in Group 1, 9.45 (6.95-11.56) in Group 2 and 6.04 (3.88-8.72) ng/mL in Group 3; the Kruskal-Wallis test result showed a significant difference between the groups (P<0.001). Following the Kruskal-Wallis test, the post-hoc Dunn test was performed for binary comparison between the groups, which revealed significant differences between all groups (Group 1-Group 2, Group 1-Group 3 and Group 2-Group 3 with P=0.001, P<0.001 and P=0.008, respectively). Moreover, a significant positive correlation was found between VAS score and UCHL1 levels before treatment (r=0.884, P<0.001). UCHL1 levels of patients with migraine increase during acute attack and they can be used to assess the severity of attack and response to treatment.

Targeting BAP1 with small compound inhibitor for colon cancer treatment

BRCA1-associated protein-1 (BAP1) is a ubiquitin C-terminal hydrolase domain-containing deubiquitinase. The gene encoding BAP1 is mutated in various human cancers, including mesothelioma, uveal melanoma and renal cell carcinoma. BAP1 plays roles in many cancer-related cellular functions, including cell proliferation, cell death, and nuclear processes crucial for genome stability, such as DNA repair and replication. While these findings suggest that BAP1 functions as a tumor suppressor, recent data also suggest that BAP1 might play tumor-promoting roles in certain cancers, such as breast cancer and hematopoietic malignancies. Here, we show that BAP1 is upregulated in colon cancer cells and tissues and that BAP1 depletion reduces colon cancer cell proliferation and tumor growth. BAP1 contributes to colon cancer cell proliferation by accelerating DNA replication and suppressing replication stress and concomitant apoptosis. A recently identified BAP1 inhibitor, TG2-179-1, which seems to covalently bind to the active site of BAP1, exhibits potent cytotoxic activity against colon cancer cells, with half-maximal inhibitory concentrations of less than 10 μM, and inhibits colon tumor growth. TG2-179-1 exerts cytotoxic activity by targeting BAP1, leading to defective replication and increased apoptosis. This work therefore shows that BAP1 acts oncogenically in colon cancer and is a potential therapeutic target for this cancer. Our work also suggests that TG2-179-1 can be developed as a potential therapeutic agent for colon cancer.

Rapid Activation of Neuroinflammation in Stroke: Plasma and Extracellular Vesicles Obtained on a Mobile Stroke Unit.

Neuroinflammation is ubiquitous in acute stroke and worsens outcome. However, the precise timing of the inflammatory response is unknown, hindering the design of acute anti-inflammatory therapeutic interventions. We sought to identify the onset of the neuroinflammatory cascade using a mobile stroke unit. The study is a proof-of-concept, cohort investigation of ultra-early blood- and extracellular vesicle-derived markers of neuroinflammation and outcome in acute stroke. Blood was obtained, prehospital, on an mobile stroke unit. Outcomes were biomarker concentrations, modified Rankin Scale score, and National Institutes of Health Stroke Scale score. Forty-one adults were analyzed, including 15 patients treated on the mobile stroke unit between August 2021 and April 2022, and 26 healthy controls to establish biomarker reference levels. Median patient age was 74 (range, 36-97) years, 60% were female, and 80% White. Ten (67%) were diagnosed as stroke, with 8 (53%) confirmed and 2 likely transient ischemic attack or stroke averted by thrombolysis; 5 were stroke mimics. For strokes, median initial National Institutes of Health Stroke Scale score was 11 (range, 4-19) and 6 (75%) received tPA (tissue-type plasminogen activator). Blood was obtained a median of 58 (range, 36-133) minutes after symptom onset. Within 36 minutes after stroke, plasma IL-6 (interleukin-6), neurofilament light chain, UCH-L1 (ubiquitin C-terminal hydrolase L1), and GFAP (glial fibrillary acidic protein) were elevated by as much as 10 times normal. In EVs, MMP-9 (matrix metalloproteinase-9), CXCL4 (chemokine (C-X-C motif) ligand 4), CRP (C-reactive protein), IL-6, OPN (osteopontin), and PECAM1 (platelet and endothelial cell adhesion molecule 1) were elevated. Inflammatory markers increased rapidly in the first 2 hours and continued rising for 24 hours. The neuroinflammatory cascade was found to be activated within 36 to 133 minutes after stroke and progresses rapidly. This is earlier than observed previously in humans and suggests injury from neuroinflammation occurs faster than had been surmised. These findings could inform development of acute immunomodulatory stroke therapies and lead to new diagnostic tools and improved outcomes.