Fredric B Kraemer

• MD
• Professor (Full) at Stanford University

Background: Fatty acids (FAs) have important roles in many cellular functions. Dysregulation of FA flux is both a characteristic and effector of many prevalent clinical conditions, including diabetes mellitus, obesity as well as insulin resistance and/or metabolic syndrome. Adipocytes take up long chain fatty acids through diffusion and protein med...

How progenitor cells can attain a distinct differentiated cell identity is a challenging problem given the fluctuating signaling environment in which cells exist and that critical transcription factors are often not unique to a differentiation process. Here, we test the hypothesis that a unique differentiated cell identity can result from a core co...

Cholesteryl ester-rich lipid droplets accumulate in steroidogenic tissues under physiological conditions and constitute an important source of cholesterol as the precursor for the synthesis of all steroid hormones. The mechanisms specifically involved in cholesteryl ester-rich lipid droplet formation have not been directly studied and are assumed b...

Disruption of circadian glucocorticoid oscillations in Cushing’s disease and chronic stress results in obesity and adipocyte hypertrophy, which is believed to be a main source of the harmful effects of obesity. Here, we recapitulate stress due to jet lag or work-life imbalances by flattening glucocorticoid oscillations in mice. Within 3 days, mice...

There is an inverse relationship between the differentiation of mesenchymal stem cells (MSCs) along either an adipocyte or osteoblast lineage, with lineage differentiation known to be mediated by transcription factors PPARγ and Runx2, respectively. Endogenous ligands for PPARγ are generated during the hydrolysis of triacylglycerols to fatty acids t...

Lipid droplets (LDs) are multifunctional organelles that regulate energy storage and cellular homeostasis. The first step of triacylglycerol (TAG) hydrolysis in LDs is catalyzed by adipose triglyceride lipase (ATGL), deficiency of which results in lethal cardiac steatosis. Although hormone-sensitive lipase (HSL) functions as a diacylglycerol (DAG)...

Objective SNAP-25 is one of the key proteins involved in formation of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complexes that are at the core of hormonal secretion and synaptic transmission. Altered expression or function of SNAP-25 can contribute to the development of neuropsychiatric and metabolic disease. A d...

Hormone-sensitive lipase (HSL) hydrolyse acylglycerols, cholesteryl and retinyl esters. HSL is a key lipase in mice testis, as HSL deficiency results in male sterility. The present work study the effects of the deficiency and lack of HSL on the localization and expression of SR-BI, LDLr, and ABCA1 receptors/transporters involved in uptake and efflu...

Apart from its role in inflammation and immunity, chemerin is also involved in white adipocyte biology. To study the role of chemerin in adipocyte metabolism, we examined the function of chemerin in brown adipose tissue. Brown and white adipocyte precursors were differentiated into adipocytes in the presence of Chemerin siRNA. Chemerin‐deficient (C...

This study investigated the effects of SOD2 (MnSOD)-deficiency-induced excessive oxidative stress on ovarian steroidogenesis in vivo and isolated and cultured granulosa cells using WT and Sod2 ± mice. Basal and 48 h eCG-stimulated plasma progesterone levels were decreased ∼50% in female Sod2 ± mice, whereas plasma progesterone levels were decreased...

Long-chain acyl-CoA synthetase 4 (ACSL4) is an ACSL family member that exhibits unique substrate preference for arachidonic acid. ACSL4 has a functional role in hepatic lipid metabolism, and is dysregulated in non-alcoholic fatty liver disease. Our previous studies demonstrated AA-induced ACSL4 degradation via the ubiquitin-proteasomal pathway (UPP...

Adipocytes take up long chain fatty acids through diffusion and protein mediated transport, whereas fatty acid efflux is considered to occur by diffusion. To identify potential membrane proteins that are involved in regulating fatty acid flux in adipocytes, the expression levels of 55 membrane transporters without known function were screened in su...

Obeticholic acid (OCA) activates the farnesoid X receptor (FXR) to lower circulating total cholesterol (TC) and high density lipoprotein‐cholesterol (HDL‐C) concentrations and to stimulate fecal cholesterol excretion in mice by increasing hepatic SR‐B1 expression. Here we show that hepatic SR‐B1 depletion by an adenovirus expressing Sr‐b1 shRNA (Ad...

In recent years, the prevalence of obesity, metabolic syndrome and type 2 diabetes is increasing dramatically. They share pathophysiological mechanisms and often lead to cardiovascular diseases. The ZDSD rat was suggested as a new animal model to study diabetes and the metabolic syndrome. In the current study, we have further characterized metaboli...

Atrial fibrillation (AF) is prevalent in patients with obesity and diabetes, and such patients often exhibit cardiac steatosis. Since the role of cardiac steatosis per se in the induction of AF has not been elucidated, the present study was designed to explore the relation between cardiac steatosis and AF. Transgenic (Tg) mice with cardiac-specific...

MicroRNAs (miRNAs) are endogenous noncoding single-stranded small RNAs of ~22 nucleotides in length that post-transcriptionally repress the expression of their various target genes. They contribute to the regulation of a variety of physiologic processes including embryonic development, differentiation and proliferation, apoptosis, metabolism, hemos...

SR-B1 belongs to the class B scavenger receptor, or CD36 super family. SR-B1 and CD36 share an affinity for a wide array of ligands. Although they exhibit similar ligand binding specificity, SR-B1 and CD36 have some very specific lipid transport functions. Whereas SR-B1 primarily facilitates the selective delivery of cholesteryl esters (CEs) and ch...

ACSL4 is a member of the ACSL family that catalyzes the conversion of long chain fatty acids to acyl CoAs, which are essential for fatty acid incorporation and utilization into diverse metabolic pathways including cholesteryl ester synthesis. Cholesteryl esters in steroidogenic tissues such as the adrenal gland are particularly enriched in choleste...

Creosote bush (Larrea tridentata)-derived nordihydroguaiaretic acid (NDGA) was shown to have profound effects on the core components of metabolic syndrome. This study investigated the in vivo potential of NDGA for prevention or attenuation of the pathophysiologic abnormalities of NASH. A novel dietary NASH model with feeding C57BL/6J mice with a hi...

Long-chain acyl-CoA synthetase 4 (ACSL4) has a unique substrate specificity for arachidonic acid. Hepatic ACSL4 is coregulated with the phospholipid (PL)-remodeling enzyme lysophosphatidylcholine (LPC) acyltransferase 3 by peroxisome proliferator-activated receptor δ to modulate the plasma triglyceride (TG) metabolism. In this study, we investigate...

Background and Purpose Previous studies have shown that Creosote bush‐derived nordihydroguaiaretic acid (NDGA) exerts beneficial actions on the key components of metabolic syndrome including dyslipidaemia, insulin resistance and hypertension in several relevant rodent models. Here, we synthesized and screened a total of 6 anti‐hyperlipidaemic analo...

Objective— The objective of this study was to determine whether and how activation of farnesoid X receptor (FXR) by obeticholic acid (OCA), a clinical FXR agonist, modulates liver low-density lipoprotein receptor (LDLR) expression under normolipidemic conditions. Approach and Results— Administration of OCA to chow-fed mice increased mRNA and prote...

Cholesterol is an important component of plasma membranes (PMs) and the precursor of all steroid hormones. In steroidogenic tissues, upon hormone stimulation, there is a rapid transfer of cholesterol to the mitochondria, which is the site of the initial step in steroidogenesis. In the current study, we examined PM cholesterol trafficking for steroi...

Cholesterol is required for maintenance of plasma membrane fluidity and integrity and for many cellular functions. Cellular cholesterol can be obtained from lipoproteins in a selective pathway of HDL-cholesteryl ester (CE) uptake without parallel apolipoprotein uptake. Scavenger receptor B type 1 (SR-B1) is a cell surface HDL receptor that mediates...

Atrial fibrillation (AF) is prevalent among diabetic patients. Diabetes is also associated with myocardial lipid droplet accumulation (steatosis), which is thought to be a source of intracellular lipotoxicity. Since the relative contribution of cardiac steatosis per se to AF has not been elucidated, the current study was designed to clarify the cau...

The liver is the central organ for ketone body production, and HMG-CoA synthase2 (HMGCS2) is a rate-limiting enzyme involved in this process. We reported that fasting markedly increased mRNA expression of HMGCS2 in mouse heart, whereas its protein expression was faint and increased only marginally with fasting. To clarify the pathophysiological rol...

Lipotoxic cardiomyopathy, which is associated with obesity and diabetes, is characterized by intracellular triacylglycerol (TAG) droplet accumulation (steatosis). The first step of TAG hydrolysis is catalyzed by adipose triglyceride lipase (ATGL), and its deficiency results in extreme cardiac steatosis in mice and humans. Although hormone-sensitive...

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To determine the effects of NDGA on metabolic and molecular changes in response to feeding mice typical American fast food or Western diet, mice were fed with ALIOS diet and subjected to metabolic analysis. Male C57BL/6J mice were randomly assigned to: ALIOS, ALIOS + NDGA, or control diet and maintained on the specific diet for 8 weeks. Mice fed AL...

The scavenger receptor, class B type 1 (SR-B1), is a multiligand membrane receptor protein that functions as a physiologically relevant high-density lipoprotein (HDL) receptor whose primary role is to mediate selective uptake or influx of HDL-derived cholesteryl esters into cells and tissues. SR-B1 also facilitates the efflux of cholesterol from pe...

The Wnt pathway is a new target in bone therapeutic space. WNT proteins are potent stem cell activators and pro-osteogenic agents. Here, we gained insights into the molecular and cellular mechanisms responsible for liposome-reconstituted recombinant human WNT3A protein (L-WNT3A) efficacy to treat osteonecrotic defects. Skeletal injuries were couple...

Cardiac intracellular lipid accumulation (steatosis) is a pathophysiological phenomenon observed in starvation and diabetes mellitus. Perilipin 2 (PLIN2) is a lipid droplet (LD)-associated protein expressed in non-adipose tissues, including the heart. To explore the pathophysiological function of myocardial PLIN2, we generated transgenic (Tg) mice...

miR-132 is hormonally regulated in steroidogenic cells of the adrenal gland, ovary and testis. Here, we examined the potential role of miR-132 in the control of steroidogenesis. Transfection of Y1 adrenal cells with miR-132 increased mRNAs of 3β-HSD and 20α-HSD enzymes, which catalyze the sequential conversion of pregnenolone to progesterone to bio...

The PPARs are a subfamily of three ligand-inducible transcription factors, which belong to the superfamily of nuclear hormone receptors. In mammals, the PPAR subfamily consists of three members: PPAR-α, PPAR-β/δ and PPAR-γ. PPARs control the expression of a large number of genes involved in metabolic homeostasis, lipid, glucose and energy metabolis...

This article provides a comprehensive review about the molecular and metabolic actions of PPAR-α. It describes its structural features, ligand specificity, gene transcription mechanisms, functional characteristics and target genes. In addition, recent progress with the use of loss of function and gain of function mouse models in the discovery of di...

Steroid hormones are produced in the adrenal cortex, testis, ovary, placenta and some peripheral tissues such as adipose tissue and brain (neurosteroids). They play important roles in carbohydrate metabolism (glucocorticoids), mineral balance (mineralocorticoids) and reproductive functions (gonadal steroids). Steroids also play a role in several ot...

Nordihydroguaiaretic acid (NDGA), the main metabolite of Creosote Bush, has been shown to have profound effects on the core components of metabolic syndrome, including lowering of blood glucose, free fatty acids and triglyceride levels, attenuating elevated blood pressure in several rodent models of dyslipidemia, and improving body weight, insulin...

Steroidogenesis is a complex process through which cholesterol traffics to mitochondria and is converted via a series of enzymatic steps to steroid hormones. Although the rate-limiting step in this process is the movement of cholesterol from the outer to the inner mitochondrial membrane via the actions of StAR, a continuous supply of cholesterol mu...

Hormone-sensitive lipase (HSL) is an intracellular neutral lipase capable of hydrolyzing acylglycerols, as well as cholesteryl and retinyl esters. In mice, HSL deficiency results in male sterility. Lipid rafts, a plasma membrane microdomain enriched in cholesterol, sphingolipids and saturated glycerophospholipids, comprise a highly dynamic clusteri...

The adrenal gland is one of the prominent sites for steroid hormone synthesis. Lipoprotein-derived cholesterol esters (CEs) delivered via SR-B1 constitute the dominant source of cholesterol for steroidogenesis, particularly in rodents. Adrenocorticotropic hormone (ACTH) stimulates steroidogenesis through downstream actions on multiple components in...

Vesicular transport involving SNARE proteins is known to be responsible for many major cellular activities. In steroidogenic tissues, chronic hormone stimulation results in increased expression of proteins involved in the steroidogenic pathway, whereas acute hormone stimulation prompts the rapid transfer of cholesterol to the inner mitochondrial me...

Salt-inducible kinase 1 (SIK1) is a serine/threonine kinase that belongs to the stress- and energy-sensing AMPK family of kinases. SIK1 expression is rapidly induced in Y1 adrenal cells in response to ACTH via the cAMP-PKA signaling cascade, and it has been suggested that an increased level of SIK1 expression inhibits adrenal steroidogenesis by rep...

Lipid droplets (LDs) in steroidogenic tissues have a cholesteryl ester (CE) core surrounded by a phospholipid monolayer that is coated with associated proteins. Compared with other tissues, they tend to be smaller in size and more numerous in numbers. These LDs are enriched with PLIN1c, PLIN2 and PLIN3. Both CIDE A and B are found in mouse ovary. F...

Nordihydroguaiaretic acid (NDGA), the main metabolite of Creosote bush, has been shown to have profound effects on the core components of the metabolic syndrome (MetS), lowering blood glucose, free fatty acids (FFA) and triglyceride (TG) levels in several models of dyslipidemia, as well as improving body weight (obesity), insulin resistance, diabet...

Little is known about the mechanisms that allow capital breeders to rapidly mobilize large amounts of body reserves. Northern elephant seals (Mirounga angustirostris) utilize fat reserves for maternal metabolism and to create high fat milk for the pup. Hormone-sensitive lipase (HSL) has been hypothesized to be an important lipolytic enzyme in fasti...

Insulin resistance underlies metabolic disease. Visceral, but not subcutaneous, white adipose tissue (WAT) has been linked to the development of insulin resistance, potentially due to differences in regulatory protein abundance. Here we investigate how protein levels are changed in insulin resistance in different WAT depots by developing a targeted...

Over the past few decades researchers have developed a variety of methods for measuring the mechanical properties of whole cells, including traction force microscopy, atomic force microscopy (AFM), and single-cell tensile testing. Though each of these techniques provides insight into cell mechanics, most also involve some nonideal conditions for ac...

Abstracts: * AIChE 2014 Annual Meeting Abstract.pdf (251.8KB) - Uploading Abstracts

Within cells, lipids are stored in the form of lipid droplets (LDs), consisting of a neutral lipid core, surrounded by a phospholipid monolayer and an outer layer of protein. LDs typically accumulate either triacylglycerol (TAG) and diacylglycerol or cholesteryl ester (CE), depending on the type of tissue. Recently, there has been an increased inte...

Scavenger receptor class B type I (SR-BI), is a physiologically relevant HDL receptor that mediates selective uptake of lipoprotein (HDL)-derived cholesteryl ester (CE) in vitro and in vivo. Mammalian SR-BI is a 509-amino acid, ~ 82 kDa glycoprotein, that contains N- and C-terminal cytoplasmic domains, two-transmembrane domains, as well as a large...

Gerald M. Reaven, MD, could easily be epitomized as the “Father of Insulin Resistance.” (For those who do not know Dr. Reaven, he would humbly raise objection to being called Dr. Reaven rather than Jerry.) That said, Jerry is credited with developing the insulin suppression test, the first quantitative method to measure insulin-mediated glucose upt...

Steroidogenic acute regulatory protein (StAR)/StarD1, a part of a protein complex, mediates the transport of cholesterol from the outer to inner mitochondrial membrane, which is the rate limiting step for steroidogenesis, and where steroid hormone synthesis begins. Here, we examined the role of oxidant-sensitive p38 MAPKs in the regulation of StAR...

Previous studies have shown that creosote bush‐derived NDGA exerts beneficial actions on the key components of the Metabolic Syndrome including dyslipidemia, and insulin resistance (IR) in several relevant rodent models. Here we screened several synthetic analogs of NDGA with selective modification of the aromatic groups of NDGA and tested their ef...

Cell mechanical properties depend primarily on the cytoskeleton, a multifunctional network which plays a key role in cell shape, motility, and intracellular transport. Additionally, the cytoskeleton is one of the first cell components to be modified by disease. Therefore a number of biological fields would benefit greatly from a device capable of r...

Genetic variation underlying hypothalamic pituitary adrenal (HPA) axis over-activity in healthy controls and patients with severe forms of major depression has not been well explored but could explain risk for cortisol dysregulation. 95 participants were studied: 40 patients with psychotic major depression (PMD); 26 patients with nonpsychotic major...

Given the emerging roles of miRNAs as potential posttranscriptional/posttranslational regulators of the steroidogenic process in adrenocortical and gonadal cells, we sought to determine miRNA profiles in rat adrenals from animals treated with vehicle, ACTH, 17α-E2 or dexamethasone. Key observations were also confirmed using hormone (Bt2cAMP)-treate...

With the realization that lipid droplets are not merely inert fat storage organelles, but highly dynamic and actively involved in cellular lipid homeostasis, there has been an increased interest in lipid droplet biology. Recent studies have begun to unravel the roles that lipid dropletss play in cellular physiology and provide insights into the mec...

This study aimed to characterize and compare the effects of obesity on gene expression profiles in two distinct adipose depots, epididymal and bone marrow, at two different ages in mice. Alterations in gene expression were analyzed in adipocytes isolated from diet-induced obese (DIO) C57BL/6J male mice at 6 and 14 months of age and from leptin defi...

Intracellular lipid droplets (LDs) are dynamic organelles that contain a number of associated proteins including perilipin (Plin) and vimentin. Cholesteryl ester (CE)-rich LDs normally accumulate in steroidogenic cells and their mobilization is the preferred initial source of cholesterol for steroidogenesis. Plin1a, 1b and 5 were found to preferent...

Insulin resistance (IR) predisposes to type 2 diabetes and cardiovascular diseases. Adipose tissue regulates glucose and lipid metabolism, and adipocyte dysfunction is linked to the development of IR. Transcription factors are the major regulators of adipocyte function, but the profiling of nuclear proteins in IR adipocytes has never been done. Her...

SR-BI binds HDL and mediates selective delivery of cholesteryl esters (CEs) to the liver, adrenals and gonads for product formation (bile acids and steroids). Since relatively little is known about SR-BI posttranslational regulation in steroidogenic cells, we examined the roles of NHERFs in regulating SR-BI expression, SR-BI-mediated selective CE u...

Hormone-sensitive lipase (HSL) catalyzes the hydrolysis of cholesteryl esters in steroidogenic tissues and, thus, facilitates cholesterol availability for steroidogenesis. The steroidogenic acute regulatory protein (StAR) controls the rate-limiting step in steroid biosynthesis. However, the modes of action of HSL in the regulation of StAR expressio...

Hormone-sensitive lipase (HSL) is a key enzyme in the mobilization of fatty acids from intracellular stores. In mice, HSL deficiency results in male sterility caused by a major defect in spermatogenesis. The testes contain high concentrations of PUFA and specific PUFA are essential for spermatogenesis. We investigated the fatty acid composition and...

Fat specific protein 27 (FSP27), a member of the Cide family, is highly expressed in adipose tissues and is a lipid droplet (LD)-associated protein that induces the accumulation of LDs. Using a yeast two-hybrid system to examine potential interactions of FSP27 with other proteins, a direct interaction with the N-terminal region of nuclear factor of...

Creosote Bush-derived NDGA, a lipoxygenase inhibitor, possesses antioxidant properties and functions as a potent anti-hyperlipidemic agent in rodent models. Here, we examined the effect of chronic NDGA treatment of ob/ob mice on plasma dyslipidemia, hepatic steatosis and changes in hepatic gene expression. Feeding ob/ob mice a chow diet supplemente...

The current studies sought to identify and characterize miRNAs that post-transcriptionally regulate the expression of SR-BI and SR-BI-linked selective HDL-CE transport and steroidogenesis. Four miRNAs (miRNA-125a, miRNA-125b, miRNA-145 and miRNA-455) with a potential to regulate SR-BI were identified in silico and validated by qRT-PCR, Western blot...

There is a tight relationship between fertility and changes in cholesterol metabolism during spermatogenesis. In the testis, class B scavenger receptors (SR-B) (SR-BI, SR-BII, and LIMP II) mediate the selective uptake of cholesterol esters from HDL, which are hydrolyzed to unesterified cholesterol by hormone sensitive lipase (HSL). HSL is critical...

Introduction: Hypothalamic-pituitary-adrenal (HPA) axis dysregulation has been linked with major depression, particularly psychotic major depression (PMD), with mineralocorticoid receptors (MRs) playing a role in HPA-axis regulation and the pathophysiology of depression. Herein we hypothesize that the MR agonist fludrocortisone differentially inhi...

In steroidogenic tissues, cholesterol must be transported to the inner mitochondrial membrane to be converted to pregnenolone as the first step of steroidogenesis. Whereas steroidogenic acute regulatory protein has been shown to be responsible for the transport of cholesterol from the outer to the inner mitochondrial membrane, the process of how ch...

In response to adrenergic stimulation, adipocytes undergo protein kinase A (PKA)-stimulated lipolysis. A key PKA target in this context is perilipin 1, a major regulator of lipolysis on lipid droplets (LDs). A study published in this issue of The EMBO Journal (Pidoux et al, 2011) identifies optic atrophy 1 (OPA1), a protein that regulates mitochond...

The hormonally controlled mobilization and release of fatty acids from adipocytes into the circulation is an important physiological process required for energy homeostasis. While uptake of fatty acids by adipocytes has been suggested to be predominantly protein-mediated, it is unclear whether the efflux of fatty acids also requires membrane protei...

Lipid droplets (LDs) are intracellular organelles that store neutral lipids within cells. Over the last two decades there has been a dramatic growth in our understanding of LD biology and, in parallel, our understanding of the role of LDs in health and disease. In its simplest form, the LD regulates the storage and hydrolysis of neutral lipids, inc...

We tested the hypothesis that the actions of hormone-sensitive lipase (HSL) affect the microenvironment of the bone marrow and that removal of HSL function by gene deletion maintains high bone mass in aging mice. We compared littermate control wild-type (WT) and HSL(-/-) mice during aging for changes in serum biochemical values, trabecular bone den...

While an increase in bone marrow adiposity is associated with age-related bone disease, the function of bone marrow adipocytes has not been studied. The aim of this study was to characterize and compare the age-related gene expression profiles in bone marrow adipocytes and epididymal adipocytes. A total of 3918 (13.7%) genes were differentially exp...

Figure S1: Evaluation of gene expression microarray data sets. RNA from bone marrow and epididymal white adipocytes (three samples each age group) was converted to cDNA, labeled and hybridized to Affymetrix Mouse Gene 1.0 ST arrays. Scanned data were imported into Partek Genomics Suit Software and normalized using RMA algorithim. A plot of frequenc...

Table S1: List of primers for qRT-PCR.

Inflammatory mediators have the potential to impact a surprising range of diseases, including obesity, obesity associated metabolic syndrome, and autoimmunity. Adipocyte development and their function in lipid storage and metabolism are regulated in a complex fashion by inflammatory cytokines. Although IL-17 appears to mediate inflammation-associat...

The mechanisms through which bone marrow adipocytes might influence differentiation and function of osteoblasts are not completely understood. To investigate the direct effects of bone marrow fat cells on osteoblast function, an ex vivo co-culture system was utilized comprising either primary fat cells or differentiated 3T3-L1 adipocytes and osteob...

Hormone-sensitive lipase (HSL) is rate limiting for diacylglycerol and cholesteryl ester hydrolysis in adipose tissue and essential for complete hormone-stimulated lipolysis. Gene expression profiling in HSL-/- mice suggests that HSL is important for modulating adipogenesis and adipose metabolism. To test whether HSL is required for the supply of i...

Inflammatory mediators have the potential to impact a surprising range of diseases, including obesity and its associated metabolic syndrome. In this paper, we show that the proinflammatory cytokine IL-17 inhibits adipogenesis, moderates adipose tissue (AT) accumulation, and regulates glucose metabolism in mice. IL-17 deficiency enhances diet-induce...

We investigated the role of proprotein convertase subtilisin/kexin type 9 (PCSK9) in the resistance of dyslipidemic hamsters to statin-induced LDL-cholesterol (LDL-C) reduction and the molecular mechanism by which statins modulated PCSK9 gene expression in vivo. We utilized the fructose diet-induced dyslipidemic hamsters as an in vivo model and ros...

Lipolysis involves a number of components including signaling pathways, droplet-associated proteins, and lipases such as hormone-sensitive lipase (HSL). We used surface enhanced laser desorption/ionization time-of-flight mass spectroscopy to identify cellular proteins that might interact with HSL and potentially influence lipolysis. Using recombina...

Increased fatty acid (FA) flux and intracellular lipid accumulation (steatosis) give rise to cardiac lipotoxicity in both pathological and physiological conditions. Since hormone-sensitive lipase (HSL) contributes to intracellular lipolysis in adipose tissue and heart, we investigated the impact of HSL disruption on cardiac energy metabolism in res...

Adipocyte lipolysis is controlled by complex interactions of lipases, cofactors, and structural proteins associated with lipid droplets. Perilipin (Plin) A is a major droplet-associated protein that functions as a scaffold, both suppressing basal and facilitating cAMP-dependent protein kinase (PKA)-stimulated lipolysis. Plin is required for the tra...