Citations

The brain, as one of the most lipid-rich organs, heavily relies on lipid transport and distribution to maintain homeostasis and neuronal function. Lipid transport mediated by lipoprotein particles, which are complex structures composed of apolipoproteins and lipids, has been thoroughly characterized in the periphery. Although lipoproteins in the central nervous system (CNS) were reported over half a century ago, the identification of APOE4 as the strongest genetic risk factor for Alzheimer's disease has accelerated investigation of the biology and pathobiology of lipoproteins in the CNS. This review provides an overview of the different components of lipoprotein particles, in particular apolipoproteins, and their involvements in both physiological functions and pathological mechanisms in the CNS.

Age at depressive onset (AAO) corresponds to unique symptomatology and clinical outcomes. Integration of genome-wide association study (GWAS) results with additional “omic” measures to evaluate AAO has not been reported and may reveal novel markers of susceptibility and/or resistance to major depressive disorder (MDD). To address this gap, we integrated genomics with metabolomics using data-driven network analysis to characterize and differentiate MDD based on AAO. This study first performed two GWAS for AAO as a continuous trait in (a) 486 adults from the Pharmacogenomic Research Network-Antidepressant Medication Pharmacogenomic Study (PGRN-AMPS), and (b) 295 adults from the Combining Medications to Enhance Depression Outcomes (CO-MED) study. Variants from top signals were integrated with 153 p180-assayed metabolites to establish multi-omics network characterizations of early (<age 18) and adult-onset depression. The most significant variant (p = 8.77 × 10−8) localized to an intron of SAMD3. In silico functional annotation of top signals (p < 1 × 10−5) demonstrated gene expression enrichment in the brain and during embryonic development. Network analysis identified differential associations between four variants (in/near INTU, FAT1, CNTN6, and TM9SF2) and plasma metabolites (phosphatidylcholines, carnitines, biogenic amines, and amino acids) in early- compared with adult-onset MDD. Multi-omics integration identified differential biosignatures of early- and adult-onset MDD. These biosignatures call for future studies to follow participants from childhood through adulthood and collect repeated -omics and neuroimaging measures to validate and deeply characterize the biomarkers of susceptibility and/or resistance to MDD development.

Significance Statement The only treatment approved for PKD inhibits production of cAMP, the main PKA activator. It is only partially effective, likely because side effects restrict dosing and because other sources of cAMP and mechanisms of cAMP-independent PKA activation exist. Which PKA isozyme(s) promotes PKD is uncertain and selective PKA inhibitors usable in vivo have not been available. Experiments in a mouse model show PKA-I is the main PKA isozyme promoting cystogenesis and that constitutive PKA-I downregulation and a novel, highly selective PKA inhibitor ameliorate PKD. The dose of PKA inhibitor used had no detectable adverse effects. This information provides a strong rationale for a strategy that may be more effective, or substantially increase the efficacy of the currently approved treatment. Background Upregulation of cAMP-dependent and cAMP-independent PKA signaling is thought to promote cystogenesis in polycystic kidney disease (PKD). PKA-I regulatory subunit RI α is increased in kidneys of orthologous mouse models. Kidney-specific knockout of RI α upregulates PKA activity, induces cystic disease in wild-type mice, and aggravates it in Pkd1 RC/RC mice. Methods PKA-I activation or inhibition was compared with EPAC activation or PKA-II inhibition using Pkd1 RC/RC metanephric organ cultures. The effect of constitutive PKA (preferentially PKA-I) downregulation in vivo was ascertained by kidney-specific expression of a dominant negative RIαB allele in Pkd1 RC/RC mice obtained by crossing Prkar1α R1αB/WT , Pkd1RC/RC , and Pkhd1- Cre mice (C57BL/6 background). The effect of pharmacologic PKA inhibition using a novel, selective PRKACA inhibitor (BLU2864) was tested in mIMCD3 3D cultures, metanephric organ cultures, and Pkd1RC/RC mice on a C57BL/6 × 129S6/Sv F1 background. Mice were sacrificed at 16 weeks of age. Results PKA-I activation promoted and inhibition prevented ex vivo P-Ser133 CREB expression and cystogenesis. EPAC activation or PKA-II inhibition had no or only minor effects. BLU2864 inhibited in vitro mIMCD3 cystogenesis and ex vivo P-Ser133 CREB expression and cystogenesis. Genetic downregulation of PKA activity and BLU2864 directly and/or indirectly inhibited many pro-proliferative pathways and were both protective in vivo . BLU2864 had no detectable on- or off-target adverse effects. Conclusions PKA-I is the main PKA isozyme promoting cystogenesis. Direct PKA inhibition may be an effective strategy to treat PKD and other conditions where PKA signaling is upregulated. By acting directly on PKA, the inhibition may be more effective than or substantially increase the efficacy of treatments that only affect PKA activity by lowering cAMP.

Over the recent years, the treatment of multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) has evolved very rapidly and a large number of disease-modifying treatments (DMTs) are now available. However, most DMTs are associated with adverse events, the most frequent of which being infections. Consideration of all DMT-associated risks facilitates development of risk mitigation strategies. An international focused workshop with expert-led discussions was sponsored by the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) and was held in April 2021 to review our current knowledge about the risk of infections associated with the use of DMTs for people with MS and NMOSD and corresponding risk mitigation strategies. The workshop addressed DMT-associated infections in specific populations, such as children and pregnant women with MS, or people with MS who have other comorbidities or live in regions with an exceptionally high infection burden. Finally, we reviewed the topic of DMT-associated infectious risks in the context of the current SARS-CoV-2 pandemic. Herein, we summarize available evidence and identify gaps in knowledge which justify further research.

AbstractBackgroundCenters discard high kidney donor profile index (KDPI) allografts, potentially related to delayed graft function and prolonged hospital use by kidney transplant recipients (KTR). We sought to determine whether high KDPI KTRs have excess health care utilization.MethodsWe conducted a retrospective cohort study from a high‐volume center analyzing KTRs from January 3, 2011 to April 12, 2015 (n = 652). We measured differences in hospital use, emergency visits, and outpatient visits within the first 90 days between low (≤85%) versus high KDPI (>85%) KTRs, as well as long‐term graft function and patient survival.ResultsHigh (n = 107) and low KDPI (n = 545) KTRs had similar length of stay (median = 3 days, P = .66), and readmission rates at 7, 30, and 90 days after surgery (all, P > .05). High KDPI kidneys were not associated with excess utilization of the hospital, emergency services, outpatient transplant clinics, or ambulatory infusion visits on univariate or multivariate analysis (all, P > .05). Low KDPI KTRs had significantly better eGFR at 2 years (Low vs. High KDPI: 60.35 vs. 41.54 ml/min, P < .001), but similar 3‐year patient and graft survival (both, P > .09).ConclusionsHigh and low KDPI KTRs demonstrated similar 90‐day risk‐adjusted health care utilization, which should encourage use of high KDPI kidneys.

165 Background: A prior study of patients with advanced cancers treated with immune checkpoint inhibitors (ICI) associated improved overall survival with tissue tumor mutational burden above the 80th percentile in each histology (tTMB-H). TMB can also reliably be calculated via liquid biopsy (bTMB), and trends higher than tTMB in analogous tumors. Here, we generate a plasma-informed benchmark for bTMB-H in advanced prostate cancer and report preliminary data from an ongoing multi-institutional case series of patients treated with ICI. Methods: Circulating tumor DNA (ctDNA) next generation sequencing (NGS) results from 3,504 patients with advanced prostate cancer who received a Guardant360 liquid biopsy within a 12-month period were analyzed. The 80th percentile of TMB was defined as the benchmark for bTMB-H in this cohort, and prevalence of microsatellite instability (MSI-H) was determined. Subsequently, clinical data were collected from patients across five institutions who received pembrolizumab based on bTMB scores or other tumor characteristics (i.e. CDK12 mutation). Results: Overall, mean and median bTMB were calculated as 12.34 mut/Mb and 8.61 mut/Mb, respectively (range: 0 – 1164.75 mut/Mb). The 80th percentile of bTMB was 13.4 mut/Mb and the 90th percentile was 16.6 mut/Mb. 2.6% of patients were both MSI-H and bTMB-H. No patients with bTMB < 13.4 mut/Mb (TMB-L) were found to be MSI-H. Ten patients from five institutions received pembrolizumab (8 monotherapy) after a median of 4.5 lines of prior therapy (Table). Four patients were MSI-H. The 3 patients in the cohort with PSA decreases > 50% had both MSI-H and bTMB ≥ 13.4 mut/Mb. Per RECIST criteria, disease was controlled (CR, PR, SD) in 6 of 7 (86%) patients with bTMB scores ≥ 13.4 mut/Mb. Conclusions: These data continue to affirm that ctDNA NGS is a practical and cost-effective means of assessing potential predictors of ICI activity in patients with advanced prostate cancer. Preliminary data from this growing cohort of patients who have received ICI guided by bTMB scores and other molecular parameters identified via ctDNA NGS, including MSI-H, demonstrate a clinical benefit from therapy. Further studies are warranted for contextualizing individual tumor bTMB scores with established, pathology-specific benchmarks.[Table: see text]

Abstract Background. There is controversy regarding the impact of delayed graft function (DGF) on kidney transplant outcomes. We hypothesize that the duration of DGF, rather than DGF itself, is associated with long-term kidney graft function.Methods. We analyzed all deceased donor kidney transplants (DDKT) done at our center between 2008 to 2020 with DGF to determine factors associated with DGF duration as well as the impact of DGF duration on 1) acute rejection, BKV infection, progression of fibrosis on protocol biopsy, and death censored graft survival 2) resource utilization, including hospital length of stay and readmissions. DGF duration was assessed at three 14-day intervals: <14 DGF days, 14-27 DGF days, >28 DGF days.Results. There were 1714 DDKT were included, 59.4% (n=1018) had DGF. The median DGF duration was 10 days IQR (6,15). The majority of recipients (95%) had resolution of DGF within 28 days. Donor factors associated with DGF days were longer cold ischemia time, donor on inotropes, older age, donation after circulatory death, higher terminal creatinine, and hypertension. Recipient factors associated with increased DGF duration included male sex, length on dialysis before transplant, and higher body mass index. There were no differences in acute rejection events or interstitial fibrosis progression by 4 months when comparing DGF days. The median length of stay was 3 days. However, readmissions increased with increasing DGF duration. Death-censored graft survival was not associated with the length of DGF except when DGF lasted >28 days. Conclusions. Inferior graft survival was observed only in recipients of DDKT with DGF lasting beyond 28 days. DGF lasting <28 days had no impact on graft survival. Duration of DGF, rather than DGF itself, is associated with graft survival. Trial Registration. Retrospective study approved by Mayo Clinic IRB.