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Primary hyperoxaluria type 1 is a severe inherited disorder that results in recurrent urolithiasis and renal failure. We generated an alanine-glyoxylate aminotransferase ( Agxt) Q84X nonsense mutant rat model that displayed an early onset of hyperoxaluria, spontaneous renal CaOx precipitation, bladder stone, and kidney injuries. Our results suggest an interaction of renal CaOx crystals with the activation of inflammation-, fibrosis-, and necroptosis-related pathways. In all, the AgxtQ84X rat strain has broad applicability in mechanistic studies and the development of innovative therapeutics.

Background Primary hyperoxaluria type 1 (PH1) is a rare genetic disorder caused by endogenous overproduction of hepatic oxalate, leading to hyperoxaluria, recurrent calcium oxalate kidney stones, and end‐stage renal disease. Lactate dehydrogenase (LDH) is an ideal target for diminishing oxalate production as it is responsible for glyoxylate to oxalate conversion in the liver, the last step of oxalate metabolism. Here, we investigated the therapeutic efficacy and potential side effects of clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology to ameliorate PH1 via specifically disrupting the hepatic LDH. Methods Pheochromocytoma (PC12) cells were used to assess the efficacy of cleavage of single‐guide RNAs in vitro. PH1 neonatal rats were injected with a single administration of adeno‐associated virus to deliver the CRISPR/Cas9 system that targeted LDH. Three weeks after injection, a liver biopsy was performed to detect LDH expression, liver injury, and liver metabolomics. Urinary oxalate was regularly monitored, and renal calcium oxalate deposition was evaluated after 4 weeks of 0.5% ethylene glycol challenge. After 6 months of treatment, animals were euthanized, and ex‐liver organs were harvested for toxicity analysis. Results The Ldha gene was specifically knocked out in 20% of the liver cells of PH1 rats in the treatment group, leading to a 50% lower LDH expression than that in the control group. Compared to the control groups, urinary oxalate levels were significantly decreased, and renal calcium oxalate precipitation was largely mitigated in the treatment group throughout the entire 6‐month study period. While no CRISPR/Cas9‐associated off‐target edits or hepatotoxicity were detected, we observed mild metabolic changes in the liver tricarboxylic acid (TCA) and glycolysis pathways. Conclusions CRISPR/Cas9‐mediated LDH disruption may represent an applicable new strategy for alleviating PH1 for its long‐lasting effect and low editorial efficiency requirements., CRISPR/Cas9 technology provides novel approaches for inherited monogenic diseases by targeting non‐essential enzymes. Using a rat model, we demonstrate that the AAV‐delivered CRISPR/Cas9 system is an effective and safe platform for knocking down lactate dehydrogenase and alleviating the life‐threatening primary hyperoxaluria type 1.

Purpose Ureteropelvic junction obstruction (UPJO) is the most frequent cause of congenital hydronephrosis in child. To better investigate the molecular mechanisms of this pathological process, the stenotic ureter proteome of UPJO in infants is compared with their own normal pre-stenotic segments. Experimental design Data independent acquisition-based proteomics are performed to compare proteome between pre-stenotic and stenotic ureter from nine UPJO infants. Gene ontology analysis, hierarchical cluster analysis, and network interaction are performed to characterize biological functions of significantly altered proteins. Selected significantly altered proteins are validated by western blot on another three UPJO infants. Results 15 proteins are up-regulated and 33 proteins are down-regulated during stenotic pathology. Significantly altered proteins are involved in decreased extracellular matrix and cytoskeleton organization, increased regulation of oxidative activity, and altered inflammatory associated exocytosis. Significant expression of biglycan, fibulin-1, myosin-10, cytochrome b5 are validated providing possible mechanism in UPJO which could be associated impaired smooth muscle cell, epithelial integrity, and increased oxidative stress. CONCLUSIONS AND CLINICAL RELEVANCE: This study provides molecular evidence of dysregulated extracellular matrix organization, impaired smooth muscle cell, and oxidative stress during UPJO pathology, indicating that biglycan, fibulin-1, myosin-10, cytochrome b5 might reflect the pathology of UPJO.

Adiponectin and miR-133a are key regulators in cardiac hypertrophy. However, whether APN has a potential effect on miR-133a remains unclear. In this study, we aimed to investigate whether APN could regulate miR-133a expression in Angiotensin II (Ang II) induced cardiac hypertrophy in vivo and in vitro. Lentiviral-mediated adiponectin treatment attenuated cardiac hypertrophy induced by Ang II infusion in male wistar rats as determined by reduced cell surface area and mRNA levels of atrial natriuretic peptide (ANF) and brain natriuretic peptide (BNP), also the reduced left ventricular end-diastolic posterior wall thickness (LVPWd) and end-diastolic interventricular septal thickness (IVSd). Meanwhile, APN elevated miR-133a level which was downregulated by Ang II. To further investigate the underlying molecular mechanisms, we treated neonatal rat ventricular myocytes (NRVMs) with recombinant rat APN before Ang II stimulation. Pretreating cells with recombinant APN promoted AMP-activated protein kinase (AMPK) phosphorylation and inhibited ERK activation. By using the inhibitor of AMPK or a lentiviral vector expressing AMPK short hairpin RNA (shRNA) cancelled the positive effect of APN on miR-133a. The ERK inhibitor PD98059 reversed the downregulation of miR-133a induced by Ang II. These results indicated that the AMPK activation and ERK inhibition were responsible for the positive effect of APN on miR-133a. Furthermore, adiponectin receptor 1 (AdipoR1) mRNA expression was inhibited by Ang II stimulation. The positive effects of APN on AMPK activation and miR-133a, and the inhibitory effect on ERK phosphorylation were inhibited in NRVMs transfected with lentiviral AdipoR1shRNA. In addition, APN depressed the elevated expression of connective tissue growth factor (CTGF), a direct target of miR-133a, through the AMPK pathway. Taken together, our data indicated that APN reversed miR-133a levels through AMPK activation, reduced ERK1/2 phosphorylation in cardiomyocytes stimulated with Ang II, revealing a previously undemonstrated and important link between APN and miR-133a.

The Platelet Inhibition and Patient Outcomes (PLATO, Eur J Prev Cardiol 22(6):734–42, 2015) trial shows that, in patients who have an acute coronary syndrome, treatment with ticagrelor as compared with clopidogrel significantly reduced the rate of death, but the reason is still uncertain. Both inflammation and vascular endothelian cell dysfunction play important roles in the pathophysiology of atherosclerotic plaques, but whether ticagrelor has superior anti-inflammatory effect and can improve vascular endothelial cell function to a great extent is unknown. Patients with STEMI who are scheduled to undergo emergency percutaneous coronary intervention (PCI) will be randomly assigned to receive a loading dose of ticagrelor 180 mg as the treatment group or clopidogrel 600 mg as the control group. After PCI, the treatment group will be treated with ticagrelor 90 mg twice daily while the control group will be treated with clopidogrel 75 mg once daily. The vascular endothelial function will be tested by circulating endothelial cells, and levels of inflammation will be tested by CD40 ligand (CD40L), high sensitivity C-reactive protein (hsCRP) and P-selectin. The estimated enrollment sample size will be 350 patients, including 175 in the treatment group and 175 in the control group. This study will compare the influence of ticagrelor and clopidogrel on inflammatory biomarkers and vascular endothelial function firstly for STEMI patients receiving emergency PCI and will provide evidence to identify whether ticagrelor inhibits inflammation and improves vascular endothelial cell function to a greater extent than clopidogrel or not. This trial was registered with Clinicaltrials.gov (identifier: NCT02123004 ) on 20 April 2014.