Citations

ATF6α is a critical driver of hepatic stellate cell (HSC) activation in vitro. HSC-specific deletion of Atf6a limits fibrogenesis in vivo despite increased IRE1α signaling. Conditional deletion of Ire1α from HSCs limits fibrogenic gene transcription without impacting overall fibrosis. This could be due in part to observed upregulation of the ATF6α pathway. Dual loss of Atf6a and Ire1a from HSCs worsens fibrosis in vivo through enhanced HSC activation.

AbstractBackground and purposeAlthough erenumab has demonstrated significant reduction in migraine frequency and improved quality of life in studies lasting 3 to 12 months, little is known about long‐term therapy.MethodsThis study was an open‐label, 5‐year treatment phase following a 12‐week, double‐blind, placebo‐controlled trial in adults with episodic migraine. Patients initially received open‐label erenumab 70 mg, which increased to 140 mg following a protocol amendment. Efficacy analyses included change from baseline in monthly migraine days (MMDs), monthly acute migraine‐specific medication (AMSM) days, and health‐related quality of life.ResultsOf 383 patients enrolled, 250 switched to 140 mg; 215 (56.1%) completed open‐label treatment. Mean (standard error) change in MMDs from baseline of 8.7 (0.2) days was −5.3 (0.3) days; an average reduction of 62.3% at year 5. Among patients using AMSM at baseline (6.3 [2.8] treatment days), mean change in monthly AMSM days was −4.4 (0.3) days at the end of 5 years. Patient‐reported outcomes indicated stable improvements in disability, headache impact, and migraine‐specific quality of life. Exposure‐adjusted patient incidence rates of adverse events (AEs) were 123.0/100 patient‐years; AEs were most frequently nasopharyngitis, upper respiratory tract infection, and influenza. Serious AEs (SAEs) reported by 49 patients (3.8/100 patient‐years) were mostly single occurrence. Two fatal adverse events were reported. There were no increases in incidence of AEs, SAEs, or AEs leading to treatment discontinuation over 5 years of exposure.ConclusionsTreatment with erenumab was associated with reductions in migraine frequency and improvements in health‐related quality of life that were maintained for at least 5 years. No new safety signals were observed.

Background and Aims During liver fibrosis, liver sinusoidal endothelial cells (LSECs) release angiocrine signals to recruit inflammatory cells into the liver. p300, a master regulator of gene transcription, is associated with pathological inflammatory response. Therefore, we examined how endothelial p300 regulates angiocrine signaling and inflammation related to portal hypertension and fibrogenesis. Approach and Results CCl4 or partial inferior vena cava ligation (pIVCL) was used to induce liver injury. Mice with LSEC‐specific p300 deletion (p300 LSECΔ/Δ) or C‐C motif chemokine ligand 2 (Ccl2) deficiency, nuclear factor kappa B (NFκB)–p50 knockout mice, and bromodomain containing 4 (BRD4) inhibitors in wild‐type mice were used to investigate mechanisms of inflammation regulation. Leukocytes were analyzed by mass cytometry by time‐of‐flight. Epigenetic histone marks were modified by CRISPR endonuclease‐deficient CRISPR‐associated 9‐fused with the Krüppel associated box domain (CRISPR‐dCas9‐KRAB)–mediated epigenome editing. Portal pressure and liver fibrosis were reduced in p300 LSECΔ/Δ mice compared to p300 fl/fl mice following liver injury. Accumulation of macrophages was also reduced in p300 LSECΔ/Δ mouse livers. Ccl2 was the most up‐regulated chemokine in injured LSECs, but its increase was abrogated in p300 LSECΔ/Δ mice. While the macrophage accumulation was increased in NFκB‐p50 knockout mice with enhanced NFκB activity, it was reduced in mice with LSEC‐specific Ccl2 deficiency and mice treated with specific BRD4 inhibitors. In vitro, epigenome editing of CCL2 enhancer and promoter regions by CRISPR‐dCas9‐KRAB technology repressed TNFα‐induced CCL2 transcription through H3K9 trimethylation. In contrast, TNFα activated CCL2 transcription by promoting p300 interaction with NFκB and BRD4, leading to histone H3 lysine 27 acetylation at CCL2 enhancer and promoter regions. Conclusions In summary, endothelial p300 interaction with NFκB and BRD4 increases CCL2 expression, leading to macrophage accumulation, portal hypertension, and liver fibrosis. Inhibition of p300 and its binding partners might serve as therapy in the treatment of liver diseases.