https://caltcm.memberclicks.net/assets/documents/acc_aha_chf_2013_guidelines.pdf

2013 ACCF/AHA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines

The worldwide obesity epidemic is stimulating efforts to identify host and environmental factors that affect energy balance. Comparisons of the distal gut microbiota of genetically obese mice and their lean littermates, as well as those of obese and lean human volunteers have revealed that obesity is associated with changes in the relative abundance of the two dominant bacterial divisions, the Bacteroidetes and the Firmicutes. Here we demonstrate through metagenomic and biochemical analyses that these changes affect the metabolic potential of the mouse gut microbiota. Our results indicate that the obese microbiome has an increased capacity to harvest energy from the diet. Furthermore, this trait is transmissible: colonization of germ-free mice with an 'obese microbiota' results in a significantly greater increase in total body fat than colonization with a 'lean microbiota'. These results identify the gut microbiota as an additional contributing factor to the pathophysiology of obesity.

An obesity-associated gut microbiome with increased capacity for energy harvest

The lion's share of bacteria in various environments cannot be cloned in the laboratory and thus cannot be sequenced using existing technologies. A major goal of single-cell genomics is to complement gene-centric metagenomic data with whole-genome assemblies of uncultivated organisms. Assembly of single-cell data is challenging because of highly non-uniform read coverage as well as elevated levels of sequencing errors and chimeric reads. We describe SPAdes, a new assembler for both single-cell and standard (multicell) assembly, and demonstrate that it improves on the recently released E+V-SC assembler (specialized for single-cell data) and on popular assemblers Velvet and SoapDeNovo (for multicell data). SPAdes generates single-cell assemblies, providing information about genomes of uncultivatable bacteria that vastly exceeds what may be obtained via traditional metagenomics studies. SPAdes is available online ( http://bioinf.spbau.ru/spades ). It is distributed as open source software.

SPAdes, a new genome assembly algorithm and its applications to single-cell sequencing ( 7th Annual SFAF Meeting, 2012)

http://www.klinikaikozpont.u-szeged.hu/pedia/images/pdf/CME_TEL/Full-Text/25.pdf

The Hallmarks of Aging

So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

Human biochemical genetics

Diabetes mellitus is a complex, multifactorial disorder that has an overall prevalence of about 5% in the United States. Whereas approximately 90% of diabetics have type II, or non-insulin-dependent diabetes mellitus (NIDDM), the remainder have type I, or insulin-dependent diabetes mellitus (IDDM). The prevalence of diabetes varies greatly among different ethnic groups, with rates as high as 20% in some Asian-Indian and American-Indian populations. These wide variations in prevalence are accounted for mainly by NIDDM Although the cause or causes of NIDDM are not known, the environment is clearly very important. The molecular basis for IDDM is better defined, but the primary cause remains unclear. Despite the etiologic and pathogenic differences between NIDDM and IDDM, the chronic sequelae of both forms of diabetes are the same, and vascular disease, particularly coronary heart disease (CHD), is the major cause of morbidity and mortality in diabetic patients.

Diabetes Mellitus and Vascular Disease Risk


 Objectives:
 Choline enthanolamine phosphotransferase 1 (
 CEPT1
 ), is essential for endothelial
 de novo
 lipogenesis (DNL) and is elevated in diseased peripheral arterial segments. Women are more sensitive to diet-induced DNL, and those with diabetes have higher incidence of severe peripheral arterial disease (PAD). We therefore hypothesized that women may have higher
 CEPT1
 content in diseased peripheral arteries and that murine conditional endothelial overexpression of
 CEPT1
 may lead to sex-specific differences in ischemic recovery.
 
 
 Methods:
 CEPT1
 expression was evaluated in diseased peripheral plaque of 7 women and 9 men. A murine endothelial
 CEPT1
 overexpression model was engineered with Cre-induced expression of a
 CEPT1
 transgene inserted in a C57BL/6J background. Endothelial
 CEPT1
 overexpression was evaluated using RT-PCR. Male (n=5) and female (n=5) received Streptozotocin and unilateral femoral artery ligation. Limb perfusion, appearance, and use were then evaluated. Gastrocnemius was stained with H&E, and endothelial Isolectin. Muscle fiber size and microvascular density were analyzed using Student’s t-test.
 
 
 Results:
 Compared to males, female patients have higher
 CEPT1
 in peripheral segments (n=7, p<0.005; Fig A). Murine endothelial
 CEPT1
 overexpression had a 7-fold increase in expression compared to control (Fig B). Compared to female mice, males demonstrated improved perfusion (p<0.05; Fig C,D), limb function (p<0.05; Fig E), limb appearance (p<0.05; Fig E), muscle fiber size (p<0.05; Fig F,G), but both has adequate muscle microvascular density (Fig F,H).
 
 
 Conclusion:
 This study reveals a gender difference in peripheral arterial
 CEPT1
 expression and ischemic recovery following overexpression. Differences do not appear to be directly associated with angiogenesis and may be due to underlying DNL metabolic consequences. These findings may have important implications for the prevalence of severe PAD in diabetic women.
 
 
 


Abstract 138: Sex Differences In Limb Ischemia Recovery Following Conditional Endothelial Overexpression Of Cept1

Objective: To evaluate the impact of N-acetyl-cysteine (NAC) on amputation stump perfusion and healing in patients with critical limb-threatening ischemia (CLTI). Background: Patients with CLTI are at increased risk of poor amputation site healing leading to increased procedure-associated morbidity. Methods: In a pilot, double-blind, placebo-controlled, randomized controlled trial, patients with CLTI undergoing major elective lower extremity amputation were randomized 1:1 to intravenous NAC (1200 mg twice-daily) or placebo for up to 5 days postoperatively. Primary outcomes were change in stump perfusion at postoperative day 3 (POD3) and POD5, and healing at POD30. Stumps were serially evaluated for wound healing, and tissue perfusion was evaluated using noninvasive laser-assisted fluorescent angiography. Results: Thirty-three patients were randomized to NAC (n = 16) or placebo (n = 17). Thirty-one patients were eligible for intent-to-treat analysis (NAC14; placebo17). Twenty patients (NAC7; placebo13) had amputation stump perfusion defects at POD0 and were considered high-risk for poor healing. Intent-to-treat analysis revealed no significant differences between treatment groups. Subgroup analysis of high-risk patients revealed differences in stump perfusion defect size (NAC–0.53-fold, placebo +0.71–fold; 95% confidence interval -2.11 to–0.35; P < 0.05) and healing (NAC [100%], placebo [46%]; P < 0.01) between study treatments. Conclusions: Postoperative NAC administration may improve amputation stump perfusion and healing in patients with CLTI and tissue perfusion defects at the time of amputation. Intraoperative laser-assisted fluorescent angiogra-phy may help surgeons identify high-risk patients with stump perfusion defects and provide early adjunctive interventions. Future studies can further explore the therapeutic benefits of NAC in the healing and perfusion of other surgical operative sites in high-risk individuals. Trial Registration: clinicaltrials.gov, Identifier: NCT03253328.

Impact of N-Acetyl-Cysteine on Ischemic Stumps Following Major Lower Extremity Amputation

Elevated fatty acids in the context of metabolic disease are associated with insulin resistance. Fatty acids covalently and reversibly modify proteins through a process known as palmitoylation. We hypothesized that depalmitoylation by acyl-protein thioesterases 1 and 2 (APT1 and APT2) in the liver regulates glucose metabolism. The hepatic roles of APT1 and APT2 are unknown. We deleted APT1 and/or APT2 from the livers of mice, followed by high-fat diet (HFD) feeding. We performed acyl resin-assisted capture (acyl-RAC) to isolate palmitoylated proteins from APT KO livers followed by mass spectrometry. APT1 primarily depalmitoylated proteins linked to mitochondrial function and amino acid metabolism, including glutamine and branched-chain amino acid metabolism. To identify direct substrates of APT1 and APT2, we determined the protein-protein proximity network of each APT by fusing each enzyme to the highly efficient biotin ligase, miniTurbo (mT). We expressed these APT-mT constructs in human hepatocellular carcinoma HepG2 cells, followed by purification of biotin-labeled proteins and analysis by mass spectrometry. The APT proximity networks demonstrated that both APT1 and APT2 interact with mitochondrial proteins. APT1 and APT2 were also proximal to several glutamine transporters including Slc1a5 (also known as ASCT2), the only glutamine transporter known to localize to mitochondria. Male mice with dual but not single deletion of APT1 and APT2 from the liver (DLKO mice) had impaired insulin sensitivity independent of p-Akt levels or expression of Pck1 and G6pc. Elevated overnight fasting glucose in DLKO mice was associated with increased glutamine-driven gluconeogenesis and decreased liver mass. These data suggest that APT1 and APT2 regulate hepatic glucose metabolism, insulin signaling, and amino acid flux in a functionally redundant manner. These novel findings are the first to illustrate the hepatic depalmitoylation substrates and protein-protein proximity networks of APT1 and APT2.
 
 
 S.L.Speck: None. Q.Zhang: None. D.P.Bhatt: None. S.Adak: None. G.Dong: None. X.Wei: None. C.F.Semenkovich: Consultant; Alnylam Pharmaceuticals.
 
 
 
 National Institutes of Health (T32GM007200, F30DK131830, R01HL157154, P30DK020579)


93-OR: Hepatic Acyl-Protein Thioesterases Prevent Insulin Resistance

Objective Peripheral atherosclerosis that accumulates in the extracranial carotid and lower extremity arteries can lead to significant morbidity and mortality. However, atherosclerotic disease progression is often not homogenous and is accelerated by diabetes. We previously observed increased phospholipid content in minimally (Min)-diseased arterial segments compared to maximally (Max)-diseased segments. Since Peroxisome Proliferator-Activated Receptor alpha (PPARα) is a key regulator of lipid metabolism, we hypothesized that it may have differential expression and signaling in Min vs. Max-diseased peripheral arterial segments. Methods Eighteen patients who underwent carotid endarterectomy (CEA), and 34 patients who underwent major lower extremity amputation were prospectively enrolled into a vascular tissue biobank. Min and Max-diseased segments were obtained in real-time from CEA plaque and amputated lower extremity arterial segments. mRNA and protein were isolated from specimens and the relative expression of ppara, and its downstream genes Acyl-CoA Oxidase 1 (acox1) and Carnitine Palmitoyltransferase 1A (cpt1a) were also evaluated. We evaluated gene expression and protein content relative to atherosclerotic disease severity and clinical diabetes status. Gene expression was also evaluated relative to Hemoglobin A1c and serum lipid profiles. Results In CEA segments of patients with diabetes, we observed significantly higher ppara and acox1 gene expression (p < 0.01 and p < 0.001 respectively), and higher PPARα protein content (p < 0.05). Hemoglobin A1c significantly correlated with expression of ppara (R2 = 0.66, p < 0.001), acox1 (R2 = 0.31, p < 0.05), and cpt1a (R2 = 0.4, p < 0.05). There was no significant difference in gene expression between Min vs. Max-diseased CEA plaque segments. Conversely, in lower extremity arterial segments of patients with diabetes, we observed significantly lower ppara, acox1, and cpt1a expression (p < 0.05, p < 0.001, and p < 0.0001 respectively). Interestingly, CPT1A content was lower in arterial segments of patients with diabetes (p < 0.05). Hemoglobin A1c and HDL-cholesterol had negative correlations with ppara (R2 = 0.44, p < 0.05; R2 = 0.42, p < 0.05; respectively). Conclusion This study demonstrates the significant differential expression of ppara and its immediate downstream genes in human carotid and lower extremity arteries relative to disease severity and diabetes. These findings highlight that mechanisms that influence atheroprogression in the carotid and lower extremities peripheral arteries are not homogenous and can be impacted by patient diabetes status and serum cholesterol profiles. Further elucidating these differential molecular mechanisms can help improve targeted therapy of atherosclerosis in different peripheral arterial beds.

/pdf/altered-peroxisome-proliferator-activated-receptor-alpha-265lvi45.pdf

Clay F. Semenkovich

Papers

Diabetes Mellitus and Vascular Disease Risk

Abstract 138: Sex Differences In Limb Ischemia Recovery Following Conditional Endothelial Overexpression Of Cept1

Impact of N-Acetyl-Cysteine on Ischemic Stumps Following Major Lower Extremity Amputation

93-OR: Hepatic Acyl-Protein Thioesterases Prevent Insulin Resistance

Altered Peroxisome Proliferator-Activated Receptor Alpha Signaling in Variably Diseased Peripheral Arterial Segments