PANDORA-Seq unveils the hidden small noncoding RNA landscape in atherosclerosis of LDL receptor-deficient mice

Small noncoding RNAs (sncRNAs) play diverse roles in numerous biological processes. While the widely used RNA sequencing (RNA-Seq) method has advanced sncRNA discovery, RNA modifications can interfere with the complementary DNA library construction process, preventing the discovery of highly modified sncRNAs including transfer RNA-derived small RNAs (tsRNAs) and ribosomal RNA-derived small RNAs (rsRNAs) that may have important functions in disease development. To address this technical obstacle, we recently developed a novel PANDORA-Seq (Panoramic RNA Display by Overcoming RNA Modification Aborted Sequencing) method to overcome RNA modification-elicited sequence interferences. To identify novel sncRNAs associated with atherosclerosis development, LDL receptor-deficient (LDLR^−/−) mice were fed a low-cholesterol diet or high-cholesterol diet (HCD) for 9 weeks. Total RNAs isolated from the intima were subjected to PANDORA-Seq and traditional RNA-Seq. By overcoming RNA modification-elicited limitations, PANDORA-Seq unveiled an rsRNA/tsRNA-enriched sncRNA landscape in the atherosclerotic intima of LDLR^−/− mice, which was strikingly different from that detected by traditional RNA-Seq. While microRNAs were the dominant sncRNAs detected by traditional RNA-Seq, PANDORA-Seq substantially increased the reads of rsRNAs and tsRNAs. PANDORA-Seq also detected 1,383 differentially expressed sncRNAs induced by HCD feeding, including 1,160 rsRNAs and 195 tsRNAs. One of HCD-induced intimal tsRNAs, tsRNA-Arg-CCG, may contribute to atherosclerosis development by regulating the proatherogenic gene expression in endothelial cells. Overall, PANDORA-Seq revealed a hidden rsRNA and tsRNA population associated with atherosclerosis development. These understudied tsRNAs and rsRNAs, which are much more abundant than microRNAs in the atherosclerotic intima of LDLR^−/− mice, warrant further investigations.     

Role of enterocyte Enpp2 and autotaxin in regulating lipopolysaccharide levels,systemic inflammation,and atherosclerosis

Conversion of lysophosphatidylcholine to lysophosphatidic acid (LPA) by autotaxin, a secreted phospholipase D, is a major pathway for producing LPA. We previously reported that feeding Ldlr^−/− mice standard mouse chow supplemented with unsaturated LPA or lysophosphatidylcholine qualitatively mimicked the dyslipidemia and atherosclerosis induced by feeding a Western diet (WD). Here, we report that adding unsaturated LPA to standard mouse chow also increased the content of reactive oxygen species and oxidized phospholipids (OxPLs) in jejunum mucus. To determine the role of intestinal autotaxin, enterocyte-specific Ldlr^−/−/Enpp2 KO (intestinal KO) mice were generated. In control mice, the WD increased enterocyte Enpp2 expression and raised autotaxin levels. Ex vivo, addition of OxPL to jejunum from Ldlr^−/− mice on a chow diet induced expression of Enpp2. In control mice, the WD raised OxPL levels in jejunum mucus and decreased gene expression in enterocytes for a number of peptides and proteins that affect antimicrobial activity. On the WD, the control mice developed elevated levels of lipopolysaccharide in jejunum mucus and plasma, with increased dyslipidemia and increased atherosclerosis. All these changes were reduced in the intestinal KO mice. We conclude that the WD increases the formation of intestinal OxPL, which i) induce enterocyte Enpp2 and autotaxin resulting in higher enterocyte LPA levels; that ii) contribute to the formation of reactive oxygen species that help to maintain the high OxPL levels; iii) decrease intestinal antimicrobial activity; and iv) raise plasma lipopolysaccharide levels that promote systemic inflammation and enhance atherosclerosis.     

10,12-Conjugated linoleic acid supplementation improves HDL composition and function in mice

Obesity is associated with inflammation, insulin resistance, and type 2 diabetes, which are major risk factors for CVD. One dietary component of ruminant animal foods, 10,12-conjugated linoleic acid (10,12 CLA), has been shown to promote weight loss in humans. Previous work has shown that 10,12 CLA is atheroprotective in mice by a mechanism that may be distinct from its weight loss effects, but this exact mechanism is unclear. To investigate this, we evaluated HDL composition and function in obese LDL receptor (Ldlr^?/?) mice that were losing weight because of 10,12 CLA supplementation or caloric restriction (CR; weight-matched control group) and in an obese control group consuming a high-fat high-sucrose diet. We show that 10,12 CLA-HDL exerted a stronger anti-inflammatory effect than CR- or high-fat high-sucrose-HDL in cultured adipocytes. Furthermore, the 10,12 CLA-HDL particle (HDL-P) concentration was higher, attributed to more medium- and large-sized HDL-Ps. Passive cholesterol efflux capacity of 10,12 CLA-HDL was elevated, as was expression of HDL receptor scavenger receptor class B type 1 in the aortic arch. Murine macrophages treated with 10,12 CLA in vitro exhibited increased expression of cholesterol transporters Abca1 and Abcg1, suggesting increased cholesterol efflux potential of these cells. Finally, proteomics analysis revealed elevated Apoa1 content in 10,12 CLA-HDL-Ps, consistent with a higher particle concentration, and particles were also enriched with alpha-1-antitrypsin, an emerging anti-inflammatory and antiatherosclerotic HDL-associated protein. We conclude that 10,12 CLA may therefore exert its atheroprotective effects by increasing HDL-P concentration, HDL anti-inflammatory potential, and promoting beneficial effects on cholesterol efflux.     

Insulin dysregulation drives mitochondrial cholesterol metabolite accumulation: initiating hepatic toxicity in nonalcoholic fatty liver disease

CYP7B1 catalyzes mitochondria-derived cholesterol metabolites such as (25R)26-hydroxycholesterol (26HC) and 3β-hydroxy-5-cholesten-(25R)26-oic acid (3βHCA) and facilitates their conversion to bile acids. Disruption of 26HC/3βHCA metabolism in the absence of CYP7B1 leads to neonatal liver failure. Disrupted 26HC/3βHCA metabolism with reduced hepatic CYP7B1 expression is also found in nonalcoholic steatohepatitis (NASH). The current study aimed to understand the regulatory mechanism of mitochondrial cholesterol metabolites and their contribution to onset of NASH. We used Cyp7b1^−/− mice fed a normal diet (ND), Western diet (WD), or high-cholesterol diet (HCD). Serum and liver cholesterol metabolites as well as hepatic gene expressions were comprehensively analyzed. Interestingly, 26HC/3βHCA levels were maintained at basal levels in ND-fed Cyp7b1^−/− mice livers by the reduced cholesterol transport to mitochondria, and the upregulated glucuronidation and sulfation. However, WD-fed Cyp7b1^−/− mice developed insulin resistance (IR) with subsequent 26HC/3βHCA accumulation due to overwhelmed glucuronidation/sulfation with facilitated mitochondrial cholesterol transport. Meanwhile, Cyp7b1^−/− mice fed an HCD did not develop IR or subsequent evidence of liver toxicity. HCD-fed mice livers revealed marked cholesterol accumulation but no 26HC/3βHCA accumulation. The results suggest 26HC/3βHCA-induced cytotoxicity occurs when increased cholesterol transport into mitochondria is coupled to decreased 26HC/3βHCA metabolism driven with IR. Supportive evidence for cholesterol metabolite-driven hepatotoxicity is provided in a diet-induced nonalcoholic fatty liver mouse model and by human specimen analyses. This study uncovers an insulin-mediated regulatory pathway that drives the formation and accumulation of toxic cholesterol metabolites within the hepatocyte mitochondria, mechanistically connecting IR to cholesterol metabolite-induced hepatocyte toxicity which drives nonalcoholic fatty liver disease.     

Gut microbiome-derived glycine lipids are diet-dependent modulators of hepatic injury and atherosclerosis

Oral and gut Bacteroidetes produce unique classes of serine-glycine lipodipeptides and glycine aminolipids that signal through host Toll-like receptor 2. These glycine lipids have also been detected in human arteries, but their effects on atherosclerosis are unknown. Here, we sought to investigate the bioactivity of bacterial glycine lipids in mouse models of atherosclerosis. Lipid 654 (L654), a serine-glycine lipodipeptide species, was first tested in a high-fat diet (HFD)-fed Ldlr^?/? model of atherosclerosis. Intraperitoneal administration of L654 over 7 weeks to HFD-fed Ldlr^?/? mice resulted in hypocholesterolemic effects and significantly attenuated the progression of atherosclerosis. We found that L654 also reduced liver inflammatory and extracellular matrix gene expression, which may be related to inhibition of macrophage activation as demonstrated in vivo by lower major histocompatibility complex class II gene expression and confirmed in cell experiments. In addition, L654 and other bacterial glycine lipids in feces, liver, and serum were markedly reduced alongside changes in Bacteroidetes relative abundance in HFD-fed mice. Finally, we tested the bioactivities of L654 and related lipid 567 in chow-fed Apoe^?/? mice, which displayed much higher fecal glycine lipids relative to HFD-fed Ldlr^?/? mice. Administration of L654 or lipid 567 for 7 weeks to these mice reduced the liver injury marker alanine aminotransferase, but other effects seen in Ldlr^?/? were not observed. Therefore, we conclude that conditions in which gut microbiome-derived glycine lipids are lost, such as HFD, may exacerbate the development of atherosclerosis and liver injury, whereas correction of such depletion may protect from these disorders.     

Serum opacity factor rescues fertility among female Scarb1−/− mice by reducing HDL-free cholesterol bioavailability

Human female infertility, 20% of which is idiopathic, is a public health problem for which better diagnostics and therapeutics are needed. A novel cause of infertility emerged from studies of female mice deficient in the HDL receptor gene (Scarb1). These mice are infertile and have high plasma HDL cholesterol (C) concentrations, due to elevated HDL-free cholesterol (FC), which transfers from HDL to all tissues. Previous studies have indicated that oral delivery of probucol, an HDL-lowering drug, to female Scarb1^?/? mice reduces plasma HDL-C concentrations and rescues fertility. Additionally, serum opacity factor (SOF), a bacterial virulence factor, disrupts HDL structure, and bolus SOF injection into mice reduces plasma HDL-C concentrations. Here, we discovered that delivering SOF to female Scarb1^?/? mice with an adeno-associated virus (AAV_SOF) induces constitutive SOF expression, reduces HDL-FC concentrations, and rescues fertility while normalizing ovary morphology. Although AAV_SOF did not alter ovary-FC content, the ovary-mol% FC correlated with plasma HDL-mol% FC in a fertility-dependent way. Therefore, reversing the abnormal plasma microenvironment of high plasma HDL-mol% FC in female Scarb1^-/- mice rescues fertility. These data provide the rationale to search for similar mechanistic links between HDL-mol% FC and infertility and the rescue of fertility in women by reducing plasma HDL-mol% FC.     

Comparison between genetic and pharmaceutical disruption of Ldlr expression for the development of atherosclerosis

Antisense oligonucleotides (ASOs) against Ldl receptor (Ldlr-ASO) represent a promising strategy to promote hypercholesterolemic atherosclerosis in animal models without the need for complex breeding strategies. Here, we sought to characterize and contrast atherosclerosis in mice given Ldlr-ASO with those bearing genetic Ldlr deficiency. To promote atherosclerosis, male and female C57Bl6/J mice were either given weekly injections of Ldlr-ASO (5 mg/kg once per week) or genetically deficient in Ldlr (Ldlr^?/?). Mice consumed either standard rodent chow or a diet high in saturated fat and sucrose with 0.15% added cholesterol for 16 weeks. While both models of Ldlr deficiency promoted hypercholesterolemia, Ldlr^?/? mice exhibited nearly 2-fold higher cholesterol levels than Ldlr-ASO mice, reflected by increased VLDL and LDL levels. Consistent with this, the en face atherosclerotic lesion area was 3-fold and 3.6-fold greater in male and female mice with genetic Ldlr deficiency, respectively, as compared with the modest atherosclerosis observed following Ldlr-ASO treatment. Aortic sinus lesion sizes, fibrosis, smooth muscle actin, and necrotic core areas were also larger in Ldlr^?/? mice, suggesting a more advanced phenotype. Despite a more modest effect on hypercholesterolemia, Ldlr-ASO induced greater hepatic inflammatory gene expression, macrophage accumulation, and histological lobular inflammation than was observed in Ldlr^?/? mice. We conclude Ldlr-ASO is a promising tool for the generation of complex rodent models with which to study atherosclerosis but does not promote comparable levels of hypercholesterolemia or atherosclerosis as Ldlr^?/? mice and increases hepatic inflammation. Thus, genetic Ldlr deficiency may be a superior model, depending on the proposed use.     

Ablation of pigment epithelium-derived factor receptor (PEDF-R/Pnpla2) causes photoreceptor degeneration

Photoreceptor cells express the patatin-like phospholipase domain-containing 2 (PNPLA2) gene that codes for pigment epithelium-derived factor receptor (PEDF-R) (also known as ATGL). PEDF-R exhibits phospholipase activity that mediates the neurotrophic action of its ligand PEDF. Because phospholipids are the most abundant lipid class in the retina, we investigated the role of PEDF-R in photoreceptors by generating CRISPR Pnpla2 knock-out mouse lines in a retinal degeneration-free background. Pnpla2^−/− mice had undetectable retinal Pnpla2 gene expression and PEDF-R protein levels as assayed by RT-PCR and immunofluorescence, respectively. The photoreceptors of mice deficient in PEDF-R had deformities as examined by histology and transmission electron microscopy. Pnpla2 knockdown diminished the PLA₂ enzymatic activity of PEDF-R in the retina. Lipidomic analyses revealed the accumulation of lysophosphatidyl choline-DHA and lysophosphatidyl ethanolamine-DHA in PEDF-R-deficient retinas, suggesting a possible causal link to photoreceptor dysfunction. Loss of PEDF-R decreased levels of rhodopsin, opsin, PKCα, and synaptophysin relative to controls. Pnpla2^−/− photoreceptors had surface-exposed phosphatidylserine, and their nuclei were TUNEL positive and condensed, revealing an apoptotic onset. Paralleling its structural defects, PEDF-R deficiency compromised photoreceptor function in vivo as indicated by the attenuation of photoreceptor a- and b-waves in Pnpla2^−/− and Pnpla2^+/− mice relative to controls as determined by electroretinography. In conclusion, ablation of PEDF-R in mice caused alteration in phospholipid composition associated with malformation and malperformance of photoreceptors. These findings identify PEDF-R as an important component for photoreceptor structure and function, highlighting its role in phospholipid metabolism for retinal survival and its consequences.     

Pharmacological intervention of biosynthesized Nigella sativa silver nanoparticles against hexavalent chromium induced toxicity in male albino mice

Hexavalent chromium, toxic heavy metal, among the top-rated environmental contaminants, is declared a potent endocrine disruptor in humans and animals. The present study was planned to find harmful effects on the reproductive system caused by Cr (VI) and the ameliorative effect of Nigella sativa and Nigella sativa-mediated AgNP on male mice (Mus musculus). In the present study, known infertility medicine, clomiphene citrate is also used as a positive control. The main objective of the present study was to assess the ameliorative potential of oral administration of a dose of 50 mg/kg BW clomiphene citrate (control), AgNP via chemical synthesis, Nigella sativa seed extract, and Nigella sativa-mediated AgNP against the Cr (VI) at the dose of 1.5 mg/kg BW from K₂Cr₂O₇ orally induced toxicity over eight weeks on the reproductive performance of male albino mice. Nigella sativa mediated AgNPs were characterized by UV, SEM, FTIR, and XRD. The histological analysis, smear study, antioxidant capacity test, and hormone analysis were conducted by blood samples of albino mice. Cr exposed groups showed a significant decrease in sperm head breadth (5.29 ± 0.54 µ) and length (19.54 ± 1.18 µ), middle piece length, tail length, LH (1.65 ± 0.15 ng/mL), testosterone (2.63 ± 0.29 ng/mL), SOD (61.40 ± 2.48 mmol/mL), CAT (87.40 ± 6.01 mmol/mL), GSH (1.54 ± 0.09 µmol/mL), and no of spermatogonia (1.22 ± 0.25), and spermatocytes (2.33 ± 0.943). However, FSH level (160.00 ± 4.98 ng/mL), seminiferous tubule CSA (1094.69 ± 49.76 mm²), size of spermatogonia (41.30 ± 1.24 µ), and spermatocytes (26.07 ± 1.34 µ) were significantly increased. Administration of Nigella sativa and Nigella sativa-mediated AgNPs reduced the toxicity.     

Nordic Walking Improves Cardiometabolic Parameters,Fitness Performance,and Quality of Life in Older Adults With Type 2 Diabetes

ObjectiveTo assess the effect of Nordic walking (NW) on cardiometabolic health, physical performance, and well-being in sedentary older adults with type 2 diabetes (T2D).MethodsFifteen subjects with T2D (female, 5; male, 10; age, 65 ± 6.2 years [mean ± standard deviation]; body mass index, 27.3 ± 4.9 kg/m² [mean ± standard deviation]) were enrolled in a 6-month NW training program. The fasting glucose and glycosylated hemoglobin levels, lipid profile (total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides), systolic blood pressure (SBP), and diastolic blood pressures were measured before and after the intervention. Participants’ quality of life (Short-Form Health Survey) and physical fitness (6-minute walking test) were also evaluated.ResultsCompared with baseline, NW significantly improved the fasting glucose level (103.5 ± 18.5 vs 168.7 ± 37.7 mg/dL, P = .01), SBP (121.8 ± 12.2 vs 133 ± 14.4 mm Hg, P = .02), physical fitness (759.88 ± 69 vs 615.5 ± 62.6 m, P < .001), and both mental health (54.5 ± 4.4 vs 45.7 ± 5.6, P < .01) and physical health (49.8 ± 4.7 vs 40.3 ± 5.9, P < .01). The levels of glycosylated hemoglobin (6.15% ± 0.8% vs 6.4% ± 1%, P = .46), total cholesterol (162.2 ± 31.2 vs 175.5 ± 28.8 mg/dL, P = .13), low-density lipoprotein cholesterol (95.2 ± 24.2 vs 106.3 ± 32.3 mg/dL, P = .43), and triglycerides (135.5 ± 60.8 vs 127.6 ± 57.4 mg/dL, P = 0.26) improved without reaching significance.ConclusionNW training improved the glycemic levels, SBP, physical fitness, and perception of quality of life in older adults with T2D. NW represents a suitable complementary strategy to improve the global health status in this population.     

Dalcetrapib and anacetrapib increase apolipoprotein E-containing HDL in rabbits and humans

The large HDL particles generated by administration of cholesteryl ester transfer protein inhibitors (CETPi) remain poorly characterized, despite their potential importance in the routing of cholesterol to the liver for excretion, which is the last step of the reverse cholesterol transport. Thus, the effects of the CETPi dalcetrapib and anacetrapib on HDL particle composition were studied in rabbits and humans. The association of rabbit HDL to the LDL receptor (LDLr) in vitro was also evaluated. New Zealand White rabbits receiving atorvastatin were treated with dalcetrapib or anacetrapib. A subset of patients from the dal-PLAQUE-2 study treated with dalcetrapib or placebo were also studied. In rabbits, dalcetrapib and anacetrapib increased HDL-C by more than 58% (P < 0.01) and in turn raised large apo E-containing HDL by 66% (P < 0.001) and 59% (P < 0.01), respectively. Additionally, HDL from CETPi-treated rabbits competed with human LDL for binding to the LDLr on HepG2 cells more than control HDL (P < 0.01). In humans, dalcetrapib increased concentrations of large HDL particles (+69%, P < 0.001) and apo B-depleted plasma apo E (+24%, P < 0.001), leading to the formation of apo E-containing HDL (+47%, P < 0.001) devoid of apo A-I. Overall, in rabbits and humans, CETPi increased large apo E-containing HDL particle concentration, which can interact with hepatic LDLr. The catabolism of these particles may depend on an adequate level of LDLr to contribute to reverse cholesterol transport.     

LRP1 loss in airway epithelium exacerbates smoke-induced oxidative damage and airway remodeling

The LDL receptor-related protein 1 (LRP1) partakes in metabolic and signaling events regulated in a tissue-specific manner. The function of LRP1 in airways has not been studied. We aimed to study the function of LRP1 in smoke-induced disease. We found that bronchial epithelium of patients with chronic obstructive pulmonary disease and airway epithelium of mice exposed to smoke had increased LRP1 expression. We then knocked out LRP1 in human bronchial epithelial cells in vitro and in airway epithelial club cells in mice. In vitro, LRP1 knockdown decreased cell migration and increased transforming growth factor β activation. Tamoxifen-inducible airway-specific LRP1 knockout mice (club Lrp1^?/?) induced after complete lung development had increased inflammation in the bronchoalveolar space and lung parenchyma at baseline. After 6 months of smoke exposure, club Lrp1^?/? mice showed a combined restrictive and obstructive phenotype, with lower compliance, inspiratory capacity, and forced expiratory volume_0.05/forced vital capacity than WT smoke-exposed mice. This was associated with increased values of Ashcroft fibrotic index. Proteomic analysis of room air exposed-club Lrp1^?/? mice showed significantly decreased levels of proteins involved in cytoskeleton signaling and xenobiotic detoxification as well as decreased levels of glutathione. The proteome fingerprint created by smoke eclipsed many of the original differences, but club Lrp1^?/? mice continued to have decreased lung glutathione levels and increased protein oxidative damage and airway cell proliferation. Therefore, LRP1 deficiency leads to greater lung inflammation and damage and exacerbates smoke-induced lung disease.     

Dennd5b-Deficient Mice are Resistant to PCSK9-Induced Hypercholesterolemia and Diet-Induced Hepatic Steatosis

Dennd5b plays a pivotal role in intestinal absorption of dietary lipids in mice and is associated with body mass index in humans. This study examined the impact of whole-body Dennd5b deletion on plasma lipid concentrations, atherosclerosis, and hepatic lipid metabolism in mice. Hypercholesterolemia was induced in Dennd5b^?/? mice by infection with an adeno-associated virus expressing the proprotein convertase subtilisin/kexin type 9 serine protease (PCSK9) gain-of-function mutation (PCSK9D377Y) and feeding a Western diet for 12 weeks. Body weight and plasma lipid concentrations were monitored over 12 weeks, and then aortic atherosclerosis and hepatic lipid content were quantified. Compared to Dennd5b^+/+ mice, Dennd5b^?/? mice were resistant to diet-induced weight gain and PCSK9-induced hypercholesterolemia. Atherosclerosis quantified by en face analysis and in aortic root sections, revealed significantly smaller lesions in Dennd5b^?/? compared to Dennd5b^+/+ mice. Additionally, Dennd5b^?/? mice had significantly less hepatic lipid content (triglyceride and cholesterol) compared to Dennd5b^+/+ mice. To gain insight into the basis for reduced hepatic lipids, quantitative PCR was used to measure mRNA abundance of genes involved in hepatic lipid metabolism. Key genes involved in hepatic lipid metabolism and lipid storage were differentially expressed in Dennd5b^?/? liver including Pparg, Cd36, and Pnpla3. These findings demonstrate a significant impact of Dennd5b on plasma and hepatic lipid concentrations and resistance to PCSK9-induced hypercholesterolemia in the absence of Dennd5b.     

A Pilot Study of Youth With Type 1 Diabetes Initiating Use of a Hybrid Closed-Loop System While Receiving a Behavioral Economics Intervention

ObjectiveMany youth do not use the hybrid closed-loop system for type 1 diabetes effectively. This study evaluated the impact of financial incentives for diabetes-related tasks on use of the 670G hybrid closed-loop system and on glycemia.MethodsAt auto mode initiation and for 16 weeks thereafter, participants received a flat rate for wearing and calibrating the sensor ($1/day), administering at least 3 mealtime insulin boluses per day ($1/day), and uploading ($5/week). Weekly bonuses were given for maintaining at least 70% of the time in auto mode, which were increased for persistent auto mode use from $3/week to a maximum of $13/week. If a participant failed to maintain auto mode for a week, the rewards were reset to baseline. Data from 17 participants aged 15.9 years ± 2.5 years (baseline hemoglobin A1c [HbA1c] 8.6% ± 1.1%) were collected at 6, 12, and 16 weeks. The reinforcers were withdrawn at 16 weeks, with a follow-up assessment at 24 weeks.ResultsWith reinforcers, the participants administered an average of at least 3 mealtime insulin boluses per day and wore the sensor over 70% of the time. However, auto mode use waned. HbA1c levels decreased by 0.5% after 6 weeks, and this improvement was maintained at 12 and 16 weeks (P < .05). Upon withdrawal of reinforcers, HbA1c levels increased back to baseline at 24 weeks.ConclusionCompensation for diabetes-related tasks was associated with lower HbA1c levels, consistent administration of mealtime insulin boluses, and sustained sensor use. These results support the potential of financial rewards for improving outcomes in youth with type 1 diabetes.     

Hepatic Deletion of X-Box Binding Protein 1 in FXR Null Mice Leads to Enhanced Liver Injury

FXR regulates bile acid metabolism, and FXR null (Fxr^?/?) mice have elevated bile acid levels and progressive liver injury. The inositol-requiring enzyme 1α/X-box binding protein 1 (XBP1) pathway is a protective unfolded protein response pathway activated in response to endoplasmic reticulum stress. Here, we sought to determine the role of the inositol-requiring enzyme 1α/XBP1 pathway in hepatic bile acid toxicity using the Fxr^?/? mouse model. Western blotting and quantitative PCR analysis demonstrated that hepatic XBP1 and other unfolded protein response pathways were activated in 24-week-old Fxr^?/? compared with 10-week-old Fxr^?/? mice but not in WT mice. To further determine the role of the liver XBP1 activation in older Fxr^?/? mice, we generated mice with whole-body FXR and liver-specific XBP1 double KO (DKO, Fxr^?/?Xbp1^LKO) and Fxr^?/?Xbp1^fl/fl single KO (SKO) mice and characterized the role of hepatic XBP1 in cholestatic liver injury. Histologic staining demonstrated increased liver injury and fibrosis in DKO compared with SKO mice. RNA sequencing revealed increased gene expression in apoptosis, inflammation, and cell proliferation pathways in DKO mice. The proapoptotic C/EBP-homologous protein pathway and cell cycle marker cyclin D1 were also activated in DKO mice. Furthermore, we found that total hepatic bile acid levels were similar between the two genotypes. At age 60 weeks, all DKO mice and no SKO mice spontaneously developed liver tumors. In conclusion, the hepatic XBP1 pathway is activated in older Fxr^?/? mice and has a protective role. The potential interaction between XBP1 and FXR signaling may be important in modulating the hepatocellular cholestatic stress responses.     

Regenerating islet-derived protein (Reg)3β plays a crucial role in attenuation of ileitis and colitis in mice

Regenerating islet-derived protein (Reg)3β belongs to a member of the Reg family of proteins and has pleiotropic functions, including antimicrobial activity and tissue repair. However, whether Reg3β plays a protective role in the development of colitis and ileitis has not been fully investigated. We generated transgenic mice expressing a short form of cellular FLICE-inhibitory protein (cFLIPs) that promotes necroptosis, a regulated form of cell death. cFLIPs transgenic (CFLARs Tg) mice develop severe ileitis in utero. Although Reg3β is undetectable in the small intestine of wild-type embryos, its expression is aberrantly elevated in the small intestine of CFLARs Tg embryos. To test whether elevated Reg3β attenuates or exacerbates ileitis in CFLARs Tg mice, we generated a Reg3b^?/? strain. Reg3b^?/? mice grew to adulthood without apparent abnormalities. Deletion of Reg3b in CFLARs Tg mice exacerbated the embryonic lethality of CFLARs Tg mice. Dextran sulfate sodium-induced colitis, characterized by body weight loss and infiltration of neutrophils, was exacerbated in Reg3b^?/? compared to wild-type mice. Moreover, the expression of Interleukin 6, an inflammatory cytokine and Chitinase-like 3, a marker for tissue repair macrophages was elevated in the colon of Reg3b^?/? mice compared to wild-type mice after DSS treatment. Together, these results suggest that attenuation of colitis and ileitis is a result of Reg3β′s real function.     

Use of a Continuous Glucose Monitoring System in High-Risk Hospitalized Noncritically Ill Patients With Diabetes After Cardiac Surgery and During Their Transition of Care From the Intensive Care Unit During COVID-19: A Pilot Study

ObjectiveContinuous glucose monitoring (CGM) has demonstrated benefits in managing inpatient diabetes. We initiated this single-arm pilot feasibility study during the COVID-19 pandemic in 11 patients with diabetes to determine the feasibility and accuracy of real-time CGM in patients who underwent cardiac surgery and whose care was being transitioned from the intensive care unit.MethodsA Clarke error grid analysis was used to compare CGM and point-of-care measurements. The mean absolute relative difference (MARD) of the paired measurements was calculated to assess the accuracy of CGM for glucose measurements during the first 24 hours on CGM, the remaining time on CGM, and for different chronic kidney disease (CKD) strata.ResultsOverall MARD between point-of-care and CGM measurements was 14.80%. MARD for patients without CKD IV and V with an estimated glomerular filtration rate (eGFR) of ≥20 mL/min/1.73 m² was 12.13%. Overall, 97% of the CGM values were within the no-risk zone of the Clarke error grid analysis. For the first 24 hours, a sensitivity analysis of the overall MARD for all patients and those with an eGFR of ≥20 mL/min/1.73 m² was 15.42% ± 14.44% and 12.80% ± 7.85%, respectively. Beyond the first 24 hours, overall MARD for all patients and those with an eGFR of ≥20 mL/min/1.73 m² was 14.54% ± 13.21% and 11.86% ± 7.64%, respectively.ConclusionCGM has shown great promise in optimizing inpatient diabetes management in the noncritical care setting and after the transition of care from the intensive care unit with high clinical reliability and accuracy. More studies are needed to further assess CGM in patients with advanced CKD.     

Mechanical suppression of premature ventricular complexes during catheter ablation procedures

IntroductionMechanical suppression of premature ventricular complexes (PVCs) is not a well-known observation. We retrospectively reviewed this phenomenon in the Ventricular Arrhythmia (VA) ablation procedures performed at Richard L. Roudebush Veterans Health Administration (VHA) center.MethodsData from 40 consecutive patients who underwent VA ablation at VHA, Indianapolis, IN, with 44 VA was included in the study. Demographic and electrophysiological parameter data was collected.ResultsOverall the mean age of the population was 64 ± 11 years. The phenomenon of mechanical suppression was seen in 11 PVCs. The mean age was 59 ± 15 years in the group in which mechanical suppression was seen. Of the 11 cases, the site of earliest activation was seen in the coronary sinus in 8 and in the pulmonary artery in 3. In one case catheter ablation was not performed because of proximity to the left coronary artery system. However, sustained pressure at the site with earliest electrograms (?35 ms) and 95% pacematch resulted in long-term suppression of PVCs. In the cases in which mechanical suppression was seen, there was a statistically significant reduction in PVC burden compared to pre ablation PVC load (1.1% ± 1.50% (post ablation) versus 24.04% ± 13.07% (pre ablation) versus p < 0.05).In all the 11 cases the site of mechanical suppression was also the site with earliest electrograms.ConclusionThis case series illustrates phenomenon of mechanical suppression of PVCs as an indication for good site for successful ablation in unique veteran patient population.     

Thionamide-induced Agranulocytosis: A Retrospective Analysis of 36 Patients With Hyperthyroidism

ObjectiveAgranulocytosis is a rare but serious adverse drug reaction (ADR) of thionamide antithyroid drugs (ATDs). We explored the characteristics of ADRs in patients with hyperthyroidism.MethodsThis retrospective study included 3558 inpatients with Graves disease treated in a Class A Grade 3 hospital between 2015 and 2019. The clinical presentation and laboratory workup of patients with antithyroid drug (ATD)-induced agranulocytosis was analyzed.ResultsAgranulocytosis was thought to be caused by ATDs in 36 patients. The hospital length of stay was 12 (10-16) days, and hospitalization costs were approximately $2810.89 ($2156.50-$4164.67). The median duration of ATD therapy prior to agranulocytosis development was 30 (20-40) days. Fever (83.33%) and sore throat (75%) were the most common symptoms as early signs of agranulocytosis. The lowest neutrophil counts were 0.01 (0.00-0.03) × 10⁹/L and 0.14 (0.02-0.29) × 10⁹/L in the methimazole and propylthiouracil groups, respectively (P = .037). The recovery times of agranulocytosis were 9.32 ± 2.89 days and 5.60 ± 4.10 days in the methimazole and propylthiouracil groups, respectively (P = .016). Patients with severe agranulocytosis required a longer time to recover (P < .001) and had closer to normal serum thyroxine and triiodothyronine levels. The interval between the first symptom of agranulocytosis and ATD withdrawal was 1 (0-3) day.ConclusionsPatients with agranulocytosis needed a long hospital length of stay and incurred high costs. Methimazole was prone to causing a more serious agranulocytosis than propylthiouracil. High thyroid hormone was unlikely to play a role in adverse drug reactions. Patient education is important.