Citations

High plasma cholesterol levels increase the risk of cardiovascular disease (CVD). Transintestinal Cholesterol Excretion (TICE) is a recently emerged pathway of cholesterol removal and has the potential to lower plasma cholesterol levels and confer protection against CVD. Under control conditions, TICE accounts for about 30% of fecal cholesterol loss in mice. Using a panel of knock-out and transgenic mice as well as pharmacological manipulations we show that in mice TICE is regulated by intestinal activation of the Farnesoid X Receptor (FXR), via its target Fibroblast Growth Factor 15/19 (FGF15/19). Activation of FXR by the agonist PX20606 (PX) resulted in a >10-fold increased fecal cholesterol excretion as well as TICE and 40% reduced plasma cholesterol levels. The induction of fecal cholesterol excretion and TICE was absent in PX-treated intestine-specific FXR-null mice but was regained when those mice were co-treated with FGF19. Moreover, FGF19 treatment alone was sufficient to induce fecal cholesterol loss to a similar extend as was observed in PX-treated wild-type mice. PX treatment resulted in an increased muricholate/cholate-ratio and thereby induced a more hydrophilic bile salt pool. Not surprisingly, cholesterol absorption was reduced in PX-treated mice. However, experiments in which mice were co-treated with PX and the cholesterol absorption inhibitor ezetimibe revealed that the stimulating effect of PX on fecal neutral sterol excretion and TICE were completely independent of differences in cholesterol absorption. Of note, treatment of mice with a combination of PX and ezetimibe stimulated fecal cholesterol loss and TICE so strongly that those mice lost about 60% of their entire estimated body cholesterol content each day. The stimulation of fecal cholesterol loss and TICE by PX and PX/ezetimibe treatment was severely blunted in Abcg8-KO mice and this could not be restored by hepatic reintroduction of Abcg8, indicating a decisive role for intestinal ABCG5/G8 in PX-induced fecal cholesterol loss and TICE. Our data strongly suggest that hydrophilic bile acids stimulate ABCG5/G8 activity in the intestine, leading to an increased flux of cholesterol from the body into the intestinal lumen that is subsequently excreted with the feces.

OBJECTIVE Scoliosis is common in patients with Chiari malformation type I (CM-I)–associated syringomyelia. While it is known that treatment with posterior fossa decompression (PFD) may reduce the progression of scoliosis, it is unknown if decompression with duraplasty is superior to extradural decompression. METHODS A large multicenter retrospective and prospective registry of 1257 pediatric patients with CM-I (tonsils ≥ 5 mm below the foramen magnum) and syrinx (≥ 3 mm in axial width) was reviewed for patients with scoliosis who underwent PFD with or without duraplasty. RESULTS In total, 422 patients who underwent PFD had a clinical diagnosis of scoliosis. Of these patients, 346 underwent duraplasty, 51 received extradural decompression alone, and 25 were excluded because no data were available on the type of PFD. The mean clinical follow-up was 2.6 years. Overall, there was no difference in subsequent occurrence of fusion or proportion of patients with curve progression between those with and those without a duraplasty. However, after controlling for age, sex, preoperative curve magnitude, syrinx length, syrinx width, and holocord syrinx, extradural decompression was associated with curve progression > 10°, but not increased occurrence of fusion. Older age at PFD and larger preoperative curve magnitude were independently associated with subsequent occurrence of fusion. Greater syrinx reduction after PFD of either type was associated with decreased occurrence of fusion. CONCLUSIONS In patients with CM-I, syrinx, and scoliosis undergoing PFD, there was no difference in subsequent occurrence of surgical correction of scoliosis between those receiving a duraplasty and those with an extradural decompression. However, after controlling for preoperative factors including age, syrinx characteristics, and curve magnitude, patients treated with duraplasty were less likely to have curve progression than patients treated with extradural decompression. Further study is needed to evaluate the role of duraplasty in curve stabilization after PFD.

AbstractMultiple myeloma (MM) remains an incurable disease despite incorporation of novel agents. Venetoclax, a B‐cell lymphoma 2 (BCL‐2) inhibitor is approved for some hematologic malignancies but not yet for MM, although clinical trials have shown efficacy in patients with MM, particularly those harboring t(11;14). We reviewed the medical records of relapsed and/or refractory MM patients to study the efficacy and safety of venetoclax used outside of clinical trials at Mayo Clinic between December, 2016 and March, 2019. The data cut‐off date was August 06, 2020. We identified 56 patients of whom 42 (75%) harbored t(11;14). The median number of prior therapies was six (range 1–15) and 14% of patients had received ≥10 prior lines of therapy. Fifty‐three (95%) patients were refractory to an immunomodulatory drug and proteasome inhibitor. Venetoclax was used as monotherapy or doublet, in combination with dexamethasone in 55% (n = 31) and a triplet or quadruplet in 45% of patients. No patient experienced tumor lysis syndrome. Overall response rate in 52 evaluable patients was 44%. The median time to best response was 2 months and median duration of response was 13.6 months. The median PFS for the entire cohort was 5.8 (95% CI 4.9–10.3) months and median OS was 28.4 (95% CI 14.6‐not reached) months. The presence of t(11;14) was associated with improved PFS (median 9.7 months vs. 4.2 months, p = 0.019) and OS (median not reached vs. 10.8 9 months, p = 0.015). Venetoclax demonstrates encouraging activity in heavily‐treated patients with relapsed/refractory MM, particularly the t(11;14) patient‐population.

Autoimmune liver disease (AILD) spans a spectrum of chronic disorders affecting the liver parenchyma and biliary system. Three main categories of AILD are autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), and primary sclerosing cholangitis (PSC). This review condenses the presentation and discussions of the Single Topic Conference (STC) on AILD that was held in Ottawa, Ontario, in November 2019. We cover generalities regarding disease presentation and clinical diagnosis; mechanistic themes; treatment paradigms; clinical trials, including approaches and challenges to new therapies; and looking beyond traditional disease boundaries. Although these diseases are considered autoimmune, the etiology and role of environmental triggers are poorly understood. AILDs are progressive and chronic conditions that affect survival and quality of life. Advances have been made in PBC treatment because second-line treatments are now available (obeticholic acid, bezafibrate); however, a significant proportion still present suboptimal response. AIH treatment has remained unchanged for several decades, and data suggest that fewer than 50% of patients achieve a complete response and as many as 80% develop treatment-related side effects. B-cell depletion therapy to treat AIH is in an early stage of development and has shown promising results. An effective treatment for PSC is urgently needed. Liver transplant remains the best option for patients who develop decompensated cirrhosis or hepatocellular carcinoma within specific criteria, but recurrent AILD might occur. Continued efforts are warranted to develop networks for AILD aimed at assessing geo-epidemiological, clinical, and biochemical differences to capture the new treatment era in Canada.

Background: Multiple publications demonstrate an association between time to initiation of corticosteroids and outcomes such as mortality and reversal of shock. However, the optimal time to initiate hydrocortisone remains unknown. Objective: To evaluate the impact of early versus late initiation of hydrocortisone in septic shock patients. Methods: A retrospective, multicentered, observational study was conducted. Adults admitted from July 1, 2014, to August 31, 2019, diagnosed with septic shock receiving vasopressors and low-dose hydrocortisone were evaluated. Participants were divided into the “early” group if hydrocortisone was initiated within 12 hours or “late” group if initiated after 12 hours of vasopressor initiation. The primary outcome was time to vasopressor discontinuation. Secondary outcomes included in-hospital mortality, intensive care unit (ICU) and hospital length of stay (LOS), vasopressor utilization, fluids administered, and need for renal replacement therapy. Results: A total of 198 patients were identified for inclusion in this propensity score–weighted cohort: 99 in the early group and 99 in the late group. Early initiation was associated with shorter time to vasopressor discontinuation compared with late initiation (40.7 vs 60.6 hours; P = 0.0002). There was also a reduction in ICU LOS (3.6 vs 5.1 days; P = 0.0147) and hospital LOS (8.9 vs 10.9 days; P = 0.0220) seen in the early group. There was no difference in mortality between groups. Conclusion and Relevance: In this propensity-matched cohort, administration of hydrocortisone within 12 hours from the onset of septic shock was associated with improved time to vasopressor discontinuation and reduced ICU and hospital LOS.

Getting around the blood–brain barrier The meninges comprise three membranes that surround and protect the central nervous system (CNS). Recent studies have noted the existence of myeloid cells resident there, but little is known about their ontogeny and function, and whether other meningeal immune cell populations have important roles remains unclear (see the Perspective by Nguyen and Kubes). Cugurra et al. found in mice that a large proportion of continuously replenished myeloid cells in the dura mater are not blood derived, but rather transit from cranial bone marrow through specialized channels. In models of CNS injury and neuroinflammation, the authors demonstrated that these myeloid cells have an immunoregulatory phenotype compared with their more inflammatory blood-derived counterparts. Similarly, Brioschi et al. show that the meninges host B cells that are also derived from skull bone marrow, mature locally, and likely acquire a tolerogenic phenotype. They further found that the brains of aging mice are infiltrated by a second population of age-associated B cells, which come from the periphery and may differentiate into autoantibody-secreting plasma cells after encountering CNS antigens. Together, these two studies may inform future treatment of neurological diseases. Science , abf7844, abf9277, this issue p. eabf7844 , p. eabf9277 ; see also abj8183, p. 396

TPS8052 Background: The monoclonal antibody (MoAb) daratumumab (dara) has been approved for treatment of newly diagnosed Multiple Myeloma (NDMM) in combination with lenalidomide (len) and dexamethasone (DRd) in patients who are not eligible to undergo stem cell transplantation (SCT). Ongoing trials are examining the role of adding bortezomib (Btz) to DRd, but it remains unclear if all patients benefit from a quadruplet regimen. Availability of sensitive assays to detect measurable/minimal residual disease (MRD) in MM and emerging data demonstrating significant prognostic value for attaining MRD negativity, offers an unprecedented opportunity to develop individualized treatment approaches. An important question is to identify who benefits from adding a fourth drug to the MoAb-IMiD triplet, thus individualizing therapy based on depth of response. We hypothesize that prolonged intensive therapy with the addition of Btz for consolidation and maintenance after DRd induction therapy for NDMM will improve survival outcomes with a more pronounced effect when used in MRD positive patients. Methods: Patients with NDMM, R-ISS Stage I or II, who are not eligible to undergo SCT or those willing to defer SCT to first relapse and have not received more than 1 cycle of any NDMM therapy will be enrolled, provided they have measurable disease, adequate organ and marrow function, have received no more than once cycle of therapy for MM and significant peripheral neuropathy or chronic obstructive pulmonary disease. Importantly, a dominant clone should be identified by lymphotrack assay for future MRD monitoring. Once enrolled, induction therapy will be in 28 day cycles consisting of daraSC (1800 mg) weekly for 2 cycles, every other week for cycles 3-6 and then every 4 weeks for 9 cycles, along with len 25 mg days 1-21 of each cycle and dex 40 mg (20 mg for those > 75 years) weekly. At end of 9 cycles (induction), patients will undergo MRD testing by next generation sequencing and will be classified into MRD positive or negative subgroups. Using MRD as an integral biomarker, the trial employs a randomized biomarker-stratified design as proposed by Freidlin et al. to determine efficacy for each MRD subgroup. Patients will be stratified by MRD status and R-ISS stage and randomized to receive 9 cycles of consolidation with DRd, without (control arm) or with (experimental arm) Btz (1.3 mg/m2 weekly for 3 of 4 weeks), followed by DR maintenance until progression The primary endpoint is consolidation OS. Sample size considerations rest on estimates of MRD subgroup prevalence at the end of induction and operating characteristics establishing the treatment effect within the MRD positive subgroup as primary and MRD negative subgroup as key secondary. The total accrual goal is 1450 patients. Clinical trial information: NCT04566328.

e20016 Background: An elevated serum LDH level is an adverse prognostic factor in NDMM. However, this category includes quantitative serum LDH levels that range from just over the upper limit of normal (ULN) to levels that may be 2 or more-fold higher than the ULN. This binary classification of serum LDH level of “normal versus elevated” fails to discriminate between the different disease biology that exists among NDMM patients with elevated serum LDH levels. Thus, we attempted to further stratify NDMM patients by the level of their serum LDH and determine its impact on OS. Methods: The cohort included patients diagnosed with NDMM from the Mayo Clinic, Rochester from 2003 - 2017 who were treated with novel agent induction therapy and had serum LDH levels measured at the time of diagnosis. The serum LDH levels were stratified into three levels: Normal (LDH < 222 U/L), Elevated (LDH 223-444 U/L), and Very Elevated (LDH >444 U/L or >2x upper limit of normal). Survival analysis was performed using the Kaplan-Meier survival analysis and compared via the log-rank method. Results: The cohort consists of 1,196 NDMM patients with a median age of 65 (22 – 95). R-ISS classification and cytogenetic risk were available for 968 and 970 patients respectively. The median serum LDH level was (162 U/L (3- 1260)) and an elevated LDH was present in 199 patients (17%). The median OS for patients with normal (N = 997; 83%), elevated (N = 170; 13%) and very elevated (N = 29; 3%) LDH levels were 76 months, 57 months and 23 months respectively (P < 0.001). The impact of these different levels of LDH on OS by R-ISS stage and cytogenetic risk is shown in the Table. Conclusions: A very small subset of NDMM patients has very elevated LDH levels that confer an exceptionally poor OS irrespective of R-ISS stage and cytogenetic risk. Future studies elucidating their disease biology responsible for such poor OS outcomes are warranted.[Table: see text]