RNA sequencing reveals perivascular adipose tissue plasticity in response to angiotensin II

PVAT adipocyte: energizing, modulating, and structuring vascular function during normotensive and hypertensive states

Hypertension represents the most common form of cardiovascular disease. It is characterized by significant remodeling of the various layers of the vascular system, including the outermost layer: the perivascular adipose tissue (PVAT). Given the tissue's pivotal role in regulating blood pressure, a comprehensive understanding of the changes that occur within PVAT during the progression of hypertension is essential. This article reviews the mechanisms through which PVAT modulates blood pressure, including the secretion of bioactive soluble factors, provision of mechanical support, and adipose-specific functions such as adipogenesis, lipogenesis, lipolysis, and extracellular matrix remodeling. Additionally, this review emphasizes the influence of hypertension on each of these regulatory mechanisms, thereby providing a deeper insight into the pathophysiological interplay between hypertension and PVAT biology.

Perivascular adipose tissue dysfunction contributes to thoracic aortic aneurysm development

BACKGROUND

Thoracic aortic aneurysm (TAA) is a life-threatening disease with high morbidity and mortality rates due to fatal complications such as aortic rupture. However, molecular mechanisms underlying TAA pathogenesis remain to be fully elucidated. The aorta is naturally surrounded by perivascular adipose tissue (PVAT), which produces and releases adipokines and other factors in a paracrine manner that are pivotal for vascular physiology and pathophysiology. Under healthy conditions, thoracic PVAT resembles brown adipose tissue (BAT) and maintains vascular homeostasis. In response to pathogenic stimuli, PVAT can undergo whitening and become dysfunctional, contributing to the development of vascular diseases. However, a causal relationship between PVAT dysfunction and TAA pathogenesis, as well as the underlying mechanisms, remain unknown. This study investigated the roles of PPARg (a key determinant of adipogenesis) and PRDM16 (a key determinant of brown adipocyte development) in PVAT on TAA development.

METHODS

PVAT samples from TAA patients were collected and evaluated. Mice lacking PVAT and those with dysfunctional PVAT were generated by crossbreeding Ucp1 promoter-driven Cre mice with Pparg floxed mice (brown adipocyte-specific Pparg knockout, PpargBAKO) and Prdm16 floxed mice (brown adipocyte-specific Prdm16 knockout, Prdm16BAKO), respectively. TAA formation was induced by perivascular application of porcine pancreatic elastase (PPE) and evaluated through histological staining. Luciferase reporter assays and chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) were used to determine PRDM16 target genes.

RESULTS

We found that PVAT near TAA lesions in patients exhibited reduced expression of browning markers and increased expression of whitening markers. PpargBAKO mice showed impaired PVAT development, while Prdm16BAKO mice displayed a loss of browning in PVAT. Both PpargBAKO and Prdm16BAKO mice exhibited aggravated TAA formation. We identified decorin, a small proteoglycan of the extracellular matrix, as a transcriptional repressive target gene of PRDM16. The expression of decorin was increased in dysfunctional PVAT and the plasma of TAA patients.

CONCLUSIONS

The development and maintenance of brown-like characteristics in PVAT are necessary to protect against TAA formation. PVAT dysfunction contributes to TAA development. Our study provides a promising therapeutic strategy for preventing TAA progression by inducing PVAT browning.

Role of Immune Cells in Perivascular Adipose Tissue in Vascular Injury in Hypertension

Hypertension is associated with vascular injury characterized by vascular dysfunction, remodeling, and stiffening, which contributes to end-organ damage leading to cardiovascular events and potentially death. Innate (macrophages and dendritic cells), innate-like (γδ T cells) and adaptive immune cells (T and B cells) play a role in hypertension and vascular injury. Perivascular adipose tissue that is the fourth layer of the blood vessel wall is an important homeostatic regulator of vascular tone. Increased infiltration of immune cells in perivascular adipose tissue in hypertension results in generation of oxidative stress and production of cytokines that may cause vascular injury. This review presents an overview of the role of the different immune cells that infiltrate the perivascular adipose tissue and are involved in the pathophysiology of hypertension.

Role of Perivascular Adipose Tissue in Vein Remodeling

Perivascular adipose tissue (PVAT) plays a crucial, yet underexplored, role in vein remodeling, which occurs after bypass surgery using a venous graft or creation of arteriovenous fistulae for hemodialysis access. PVAT exhibits significant heterogeneity in phenotype and tissue composition depending on the vascular bed, as well as its anatomic location within the vasculature. Through the excretion of adipokines, cytokines, and chemokines, PVAT can shape the vascular response to local and systemic perturbations. Moreover, the active exchange of cells reinforces the bidirectional cross talk between the vessel wall and PVAT. In this review, we describe the role of PVAT in relation to postinterventional vein remodeling, specifically focusing on the effect of surgery on the PVAT phenotype. Moreover, we discuss the pathophysiological mechanisms that ultimately affect clinical outcomes and highlight the therapeutic potential of PVAT to improve vein remodeling.

Sex-Specific Characteristics of Perivascular Fat in Aortic Aneurysms

Aortic aneurysms (AAs), the dilation or widening of the aorta, lead to dissection or rupture with high morbidity and mortality if untreated. AA displays gender disparities in its prevalence, progression and outcomes, with women having worse outcomes and faster aneurysm growth. However, current guidelines do not address gender dimorphism, emphasizing the urgent need for personalized treatment strategies and further research. Perivascular adipose tissue (PVAT), a unique type of fat surrounding blood vessels, plays a critical role in maintaining vasomotor tone and vascular homeostasis, with dysfunction associated with chronic inflammation and vessel-wall remodeling. Indeed, PVAT dysfunction promotes the development of aortic aneurysms, with hormonal and biomechanical factors exacerbating the pathological vascular microenvironment. The sexually dimorphic characteristics of PVAT include morphological, immunological, and hormonally mediated differences. Thus, targeting PVAT-mediated mechanisms may be a promising option for the (gender-specific) therapeutic management of cardiovascular pathologies. This review examines the emerging importance of PVAT in vascular health, its potential therapeutic implications for AA, and identifies gaps in the current state of research.

Obesity-induced mesenteric PVAT remodelling is sexually dimorphic, but not driven by ovarian hormones : Short title: Obesity induces sex-specific responses in mesenteric PVAT

BACKGROUND

Obesity, a major risk factor for cardiovascular disease (CVD), is associated with hypertension and vascular dysfunction. Perivascular adipose tissue (PVAT), a metabolically active tissue surrounding blood vessels, plays a key role in regulating vascular tone. In obesity, PVAT becomes dysregulated which may contribute to vascular dysfunction; how sex impacts the remodelling of PVAT and thus the altered vascular contractility during obesity is unclear.

OBJECTIVE

To investigate sex-specific PVAT dysregulation in the setting of obesity as a potential driver of sex differences in vascular pathologies and CVD risk.

METHODS

Adult male and female C57Bl/6J mice were fed an obesogenic high-fat diet (HFD) or regular chow for 16 weeks. Mesenteric PVAT (mPVAT) was isolated for RNA-sequencing and histological analysis, and mesenteric arteries were isolated for assessment of vascular function by wire myography. In a separate study, female mice were subjected to bilateral ovariectomy prior to dietary intervention to determine the contribution of ovarian hormones to PVAT dysregulation.

RESULTS

Transcriptomic analysis of mPVAT revealed sexually dimorphic responses to HFD, with upregulation of extracellular matrix (ECM) remodelling pathways in male but not female mice. Histological and RT-qPCR approaches demonstrated increased collagen deposition and ECM remodelling in mPVAT from obese male compared with obese female mice. Assessment of vascular function in mesenteric arteries -/+ PVAT revealed that in obesity, mPVAT impaired endothelium-mediated vasodilation in male but not female mice. Ovariectomy of female mice prior to HFD administration did not alter ECM transcript expression or collagen deposition in mPVAT compared to sham-operated female mice.

CONCLUSIONS

Obesity induces sex-specific molecular remodelling in mPVAT, with male mice exhibiting unique upregulation of ECM pathways and increased collagen deposition compared to females. Moreover, the relative protection of female mice from obesity-induced mPVAT dysregulation is not mediated by ovarian hormones. These data highlight a potential sex-specific mechanistic link between mPVAT and mesenteric artery dysfunction in obesity, and provides crucial insights for future development of treatment strategies that consider the unique cardiovascular risks in men and women.

Perivascular adipose tissue: a central player in the triad of diabetes, obesity, and cardiovascular health

Perivascular adipose tissue (PVAT) is a dynamic tissue that affects vascular function and cardiovascular health. The connection between PVAT, the immune system, obesity, and vascular disease is complex and plays a pivotal role in the pathogenesis of vascular diseases such as atherosclerosis, hypertension, and vascular inflammation. In cardiometabolic diseases, PVAT becomes a significant source of proflammatory adipokines, leading to increased infiltration of immune cells, in cardiometabolic diseases, PVAT becomes a significant source of proinflammatory adipokines, leading to increased infiltration of immune cells, promoting vascular smooth muscle cell proliferation and migrationpromoting vascular smooth muscle cell proliferation and migration. This exacerbates vascular dysfunction by impairing endothelial cell function and promoting endothelial activation. Dysregulated PVAT also contributes to hemodynamic alterations and hypertension through enhanced sympathetic nervous system activity and impaired vasodilatory capacity of PVAT-derived factors. Therapeutic interventions targeting key components of this interaction, such as modulating PVAT inflammation, restoring adipokine balance, and attenuating immune cell activation, hold promise for mitigating obesity-related vascular complications. Lifestyle interventions, pharmacological agents targeting inflammatory pathways, and surgical approaches aimed at reducing PVAT mass or improving adipose tissue function are potential therapeutic avenues for managing vascular diseases associated with obesity and PVAT dysfunction.

Impact of the local renin-angiotensin system in perivascular adipose tissue on vascular health and disease

Perivascular adipose tissue (PVAT) is found locally around blood vessels. It has the ability to release vasoactive chemicals, such as factors that relax and contract blood vessels. PVAT is now recognized as an endocrine organ with metabolic activity and as a "protagonist" for maintaining vascular homeostasis. Angiotensin II, a powerful vasoconstrictor of the renin-angiotensin system (RAS) that can increase blood pressure and vascular tone, is produced locally by PVAT. To mitigate the multiple vascular effects of angiotensin II, PVAT also generates molecules such as angiotensin (1-7), adiponectin, and nitric oxide. Reactive oxygen species and proinflammatory cytokines are produced in greater amounts when PVAT-mediated angiotensin II is present, resulting in endothelial dysfunction, inflammation, atherosclerosis, and other vascular disorders. The anticontractile and procontractile nature of PVAT is frequently disrupted in obese individuals, which increases the production of angiotensin II and decreases the production of anti-inflammatory and vasodilatory factors. These changes in turn exacerbate vascular inflammation, hypertension, and atherosclerosis. PVAT, which is crucial for maintaining vascular homeostasis, loses its anticontractile effect in obesity due to adipocyte hypertrophy, inflammation, and oxidative stress, exacerbating endothelial dysfunction. Overactive RAS in PVAT facilitates the migration and proliferation of vascular smooth muscle cells and atherosclerotic plaques, both of which accelerate the development of atherosclerosis. Targeting PVAT and the local RAS can offer therapeutic benefits in treating hypertension, atherosclerosis, and other vascular diseases. This review highlights the scientific underpinnings of the function of PVAT in regulating the autocrine and paracrine activities of vascular RAS constituents.

Cross-talks between perivascular adipose tissue and neighbors: multifaceted nature of nereids

Perivascular adipose tissue (PVAT) is a unique fat depot surrounding blood vessels and plays a vital role in the progression of vascular remodeling and dysfunction. PVAT exhibits remarkable differences in structure, phenotype, origin, and secretome across anatomical locations. The proximity of PVAT to neighboring vascular beds favors a niche for bidirectional communication between adipocytes and vascular smooth muscle cells, endothelial cells, and immune cells. In this review, we update our understanding of PVAT's regional differences and provide a comprehensive exploration of how these differences impact cross-talks between PVAT and the vascular wall. Different PVAT depots show different degrees of vasoprotective function and resilience to pathological changes such as obesity and vasculopathies, shaping multifaceted interactions between PVAT depots and adjacent vasculatures. The depot-specific resilience may lead to innovative strategies to manage cardiometabolic disorders.

Interleukin-10 deficiency induces thoracic perivascular adipose tissue whitening and vascular remodeling

Perivascular adipose tissue (PVAT) is an adipose layer, surrounding blood vessels, with a local modulatory role. Interleukin-10 (IL-10) has been shown to modulate vascular tissue. This study aimed to characterize the endogenous role of IL-10 in vascular remodeling, and PVAT phenotyping. Thoracic aortic segments from control (C57BL/6J) and IL-10 knockout (IL-10-/-) male mice were used. Analyzes of aorta/PVAT morphometry, and elastin, collagen and reticulin deposition were performed. Tissue uncoupling protein 1 (UCP1) was accessed by Western blotting. Endogenous absence of IL-10 reduced total PVAT area (p = 0.0310), and wall/lumen ratio (p = 0.0024), whereas increased vascular area and thickness (p < 0.0001). Total collagen deposition was augmented in IL-10-/-, but under polarized light, the reduction of collagen-I (p = 0.0075) and the increase of collagen-III (p = 0.0055) was found, simultaneously with reduced elastic fibers deposition (p = 0.0282) and increased deposition of reticular fibers (p < 0.0001). Adipocyte area was augmented in the IL-10 absence (p = 0.0225), and UCP1 expression was reduced (p = 0.0420). Moreover, relative frequency of white adipose cells and connective tissue was augmented in IL-10-/- (p < 0.0001), added to a reduction in brown adipose cells (p < 0.0001). Altogether, these data characterize aorta PVAT from IL-10-/- as a white-like adipocyte phenotype. Endogenous IL-10 prevents vascular remodeling and favors a brown-like adipocyte phenotype, suggesting a modulatory role for IL-10 in PVAT plasticity.

Anatomical location, sex, and age modulate adipocyte progenitor populations in perivascular adipose tissues

Perivascular adipose tissue (PVAT) regulates vascular function due to its capacity to synthesize vasoactive products and its mechanical properties. PVATs most abundant cells are adipocytes, and their populations are maintained by the maturation of adipocyte progenitor cells (APC), which may play a pivotal role in the pathogenesis of cardiovascular diseases. However, the distribution of APC within PVAT depots, their potential variation in spatial location, and the influence of sex and age on their abundance remain unknown. We hypothesize that APC abundance in PVAT is affected by location, age, sex and that APC subtypes have specific spatial distributions. PVAT from thoracic and abdominal aorta, and mesenteric arteries, and AT from interscapular, gonadal, and subcutaneous depots from 13-week and 30-week-old females and males Pdgfrα-CreERT2 x LSL-tdTomato mice (n = 28) were analyzed. Abdominal aorta PVAT had fewer progenitors than mesenteric PVAT and gonadal AT. Aging reduced the abundance of APC in the thoracic aorta but increased their numbers in mesenteric PVAT. Females had more APC than males in mesenteric PVAT and gonadal AT depots. APC exhibited unique spatial distribution in the aorta and mesenteric PVAT where they localized neighboring vasa vasorum and arteries. APC subtypes (APC1, APC2, APC3, diff APC) were identified in all PVAT depots. Thoracic aorta PVAT APC3 were located in the adventitia while diff APC were in the parenchyma. This study identified variability in APC populations based on depot, age, and sex. The distinctive spatial distribution and the presence of diverse APC subtypes suggest that they may contribute differently to cardiovascular diseases-induced PVAT remodeling.

Innervation of adipocytes is limited in mouse perivascular adipose tissue

Perivascular adipose tissue (PVAT) regulates vascular tone by releasing anticontractile factors. These anticontractile factors are driven by processes downstream of adipocyte stimulation by norepinephrine; however, whether norepinephrine originates from neural innervation or other sources is unknown. The goal of this study was to test the hypothesis that neurons innervating PVAT provide the adrenergic drive to stimulate adipocytes in aortic and mesenteric perivascular adipose tissue (aPVAT and mPVAT), and white adipose tissue (WAT). Healthy male and female mice (8-13 wk) were used in all experiments. Expression of genes associated with synaptic transmission were quantified by qPCR and adipocyte activity in response to neurotransmitters and neuron depolarization was assessed in AdipoqCre+;GCaMP5g-tdTf/WT mice. Immunostaining, tissue clearing, and transgenic reporter lines were used to assess anatomical relationships between nerves and adipocytes. Although synaptic transmission component genes are expressed in adipose tissues (aPVAT, mPVAT, and WAT), strong nerve stimulation with electrical field stimulation does not significantly trigger calcium responses in adipocytes. However, norepinephrine consistently elicits strong calcium responses in adipocytes from all adipose tissues studied. Bethanechol induces minimal adipocyte responses. Imaging neural innervation using various techniques reveals that nerve fibers primarily run alongside blood vessels and rarely branch into the adipose tissue. Although nerve fibers are associated with blood vessels in adipose tissue, they demonstrate limited anatomical and functional interactions with adjacent adipocytes, challenging the concept of classical innervation. These findings dispute the significant involvement of neural input in regulating PVAT adipocyte function and emphasize alternative mechanisms governing adrenergic-driven anticontractile functions of PVAT.NEW & NOTEWORTHY This study challenges prevailing views on neural innervation in perivascular adipose tissue (PVAT) and its role in adrenergic-driven anticontractile effects on vasculature. Contrary to existing paradigms, limited anatomical and functional connections were found between PVAT nerve fibers and adipocytes, underscoring the importance of exploring alternative mechanistic pathways. Understanding the mechanisms involved in PVAT's anticontractile effects is critical for developing potential therapeutic interventions against dysregulated vascular tone, hypertension, and cardiovascular disease.

Perivascular fat tissue and vascular aging: A sword and a shield

The understanding of the function of perivascular adipose tissue (PVAT) in vascular aging has significantly changed due to the increasing amount of information regarding its biology. Adipose tissue surrounding blood vessels is increasingly recognized as a key regulator of vascular disorders. It has significant endocrine and paracrine effects on the vasculature and is mediated by the production of a variety of bioactive chemicals. It also participates in a number of pathological regulatory processes, including oxidative stress, immunological inflammation, lipid metabolism, vasoconstriction, and dilation. Mechanisms of homeostasis and interactions between cells at the local level tightly regulate the function and secretory repertoire of PVAT, which can become dysregulated during vascular aging. The PVAT secretion group changes from being reducing inflammation and lowering cholesterol to increasing inflammation and increasing cholesterol in response to systemic or local inflammation and insulin resistance. In addition, the interaction between the PVAT and the vasculature is reciprocal, and the biological processes of PVAT are directly influenced by the pertinent indicators of vascular aging. The architectural and biological traits of PVAT, the molecular mechanism of crosstalk between PVAT and vascular aging, and the clinical correlation of vascular age-related disorders are all summarized in this review. In addition, this paper aims to elucidate and evaluate the potential benefits of therapeutically targeting PVAT in the context of mitigating vascular aging. Furthermore, it will discuss the latest advancements in technology used for targeting PVAT.

MitoNEET Provides Cardioprotection via Reducing Oxidative Damage and Conserving Mitochondrial Function

Cardiometabolic diseases exert a significant health impact, leading to a considerable economic burden globally. The metabolic syndrome, characterized by a well-defined cluster of clinical parameters, is closely linked to an elevated risk of cardiovascular disease. Current treatment strategies often focus on addressing individual aspects of metabolic syndrome. We propose that exploring novel therapeutic approaches that simultaneously target multiple facets may prove more effective in alleviating the burden of cardiometabolic disease. There is a growing body of evidence suggesting that mitochondria can serve as a pivotal target for the development of therapeutics aimed at resolving both metabolic and vascular dysfunction. MitoNEET was identified as a binding target for the thiazolidinedione (TZD) class of antidiabetic drugs and is now recognized for its role in regulating various crucial cellular processes. Indeed, mitoNEET has demonstrated promising potential as a therapeutic target in various chronic diseases, encompassing cardiovascular and metabolic diseases. In this review, we present a thorough overview of the molecular mechanisms of mitoNEET, with an emphasis on their implications for cardiometabolic diseases in more recent years. Furthermore, we explore the potential impact of these findings on the development of novel therapeutic strategies and discuss potential directions for future research.

The role of perivascular adipose tissue-secreted adipocytokines in cardiovascular disease

Perivascular adipose tissue and the vessel wall are connected through intricate bidirectional paracrine and vascular secretory signaling pathways. The secretion of inflammatory factors and oxidative products by the vessel wall in the diseased segment has the ability to influence the phenotype of perivascular adipocytes. Additionally, the secretion of adipokines by perivascular adipose tissue exacerbates the inflammatory response in the diseased vessel wall. Therefore, quantitative and qualitative studies of perivascular adipose tissue are of great value in the context of vascular inflammation and may provide a reference for the assessment of cardiovascular ischemic disease.

Perivascular Adipose Tissue Oxidative Stress in Obesity

Perivascular adipose tissue (PVAT) adheres to most systemic blood vessels in the body. Healthy PVAT exerts anticontractile effects on blood vessels and further protects against cardiovascular and metabolic diseases. Healthy PVAT regulates vascular homeostasis via secreting an array of adipokine, hormones, and growth factors. Normally, homeostatic reactive oxygen species (ROS) in PVAT act as secondary messengers in various signalling pathways and contribute to vascular tone regulation. Excessive ROS are eliminated by the antioxidant defence system in PVAT. Oxidative stress occurs when the production of ROS exceeds the endogenous antioxidant defence, leading to a redox imbalance. Oxidative stress is a pivotal pathophysiological process in cardiovascular and metabolic complications. In obesity, PVAT becomes dysfunctional and exerts detrimental effects on the blood vessels. Therefore, redox balance in PVAT emerges as a potential pathophysiological mechanism underlying obesity-induced cardiovascular diseases. In this review, we summarise new findings describing different ROS, the major sources of ROS and antioxidant defence in PVAT, as well as potential pharmacological intervention of PVAT oxidative stress in obesity.

PRDM16 deficiency in vascular smooth muscle cells aggravates abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) is usually asymptomatic until life-threatening complications occur, predominantly involving aortic rupture. Currently, no drug-based treatments are available, primarily due to limited understanding of AAA pathogenesis. The transcriptional regulator PR domain-containing protein 16 (PRDM16) is highly expressed in the aorta, but its functions in the aorta are largely unknown. By RNA-seq analysis, we found that vascular smooth muscle cell-specific (VSMC-specific) Prdm16-knockout (Prdm16SMKO) mice already showed extensive changes in the expression of genes associated with extracellular matrix (ECM) remodeling and inflammation in the abdominal aorta under normal housing conditions without any pathological stimuli. Human AAA lesions displayed lower PRDM16 expression. Periadventitial elastase application to the suprarenal region of the abdominal aorta aggravated AAA formation in Prdm16SMKO mice. During AAA development, VSMCs undergo apoptosis because of both intrinsic and environmental changes, including inflammation and ECM remodeling. Prdm16 deficiency promoted inflammation and apoptosis in VSMCs. A disintegrin and metalloproteinase 12 (ADAM12) is a gelatinase that can degrade various ECMs. We found that ADAM12 is a target of transcriptional repression by PRDM16. Adam12 knockdown reversed VSMC apoptosis induced by Prdm16 deficiency. Our study demonstrated that PRDM16 deficiency in VSMCs promoted ADAM12 expression and aggravates AAA formation, which may provide potential targets for AAA treatment.

Perivascular Adipose Tissue and Vascular Smooth Muscle Tone: Friends or Foes?

Perivascular adipose tissue (PVAT) is a specialized type of adipose tissue that surrounds most mammalian blood vessels. PVAT is a metabolically active, endocrine organ capable of regulating blood vessel tone, endothelium function, vascular smooth muscle cell growth and proliferation, and contributing critically to cardiovascular disease onset and progression. In the context of vascular tone regulation, under physiological conditions, PVAT exerts a potent anticontractile effect by releasing a plethora of vasoactive substances, including NO, H₂S, H₂O₂, prostacyclin, palmitic acid methyl ester, angiotensin 1-7, adiponectin, leptin, and omentin. However, under certain pathophysiological conditions, PVAT exerts pro-contractile effects by decreasing the production of anticontractile and increasing that of pro-contractile factors, including superoxide anion, angiotensin II, catecholamines, prostaglandins, chemerin, resistin, and visfatin. The present review discusses the regulatory effect of PVAT on vascular tone and the factors involved. In this scenario, dissecting the precise role of PVAT is a prerequisite to the development of PVAT-targeted therapies.

Myeloid TM6SF2 Deficiency Inhibits Atherosclerosis

Genetic variants in transmembrane 6 superfamily member 2 (TM6SF2), such as E167K, are associated with atherosclerotic cardiovascular disease (ASCVD). Chronic inflammation and lipid-laden macrophage foam cell formation are the central pathogeneses in the development of atherosclerosis. This study was undertaken to illustrate the biological function of TM6SF2 in macrophages and its role during atherosclerosis development. We generated myeloid cell-specific Tm6sf2 knockout mice on ApoE-deficient background (LysM Cre+/Tm6sf2fl/fl/ApoE-/-, TM6 mKO) with littermate LysM Cre-/Tm6sf2fl/fl/ApoE-/- (Control) mice as controls. Mice were fed a Western diet for 12 weeks to induce atherosclerosis. Myeloid Tm6sf2 deficiency inhibited atherosclerosis and decreased foam cells in the plaques without changing the plasma lipid profile. RNA sequencing of bone marrow-derived macrophages (BMDMs) from TM6 mKO mice demonstrated the downregulation of genes associated with inflammation, cholesterol uptake, and endoplasmic reticulum (ER) stress. TM6SF2 was upregulated by oxidized low-density lipoprotein (oxLDL) in macrophages. Silencing TM6SF2 in THP-1-derived macrophages and Tm6sf2 deficiency in BMDMs reduced inflammatory responses and ER stress and attenuated cholesterol uptake and foam cell formation, while the overexpression of TM6SF2 showed opposite effects. In conclusion, myeloid TM6SF2 deficiency inhibits atherosclerosis development and is a potential therapeutic target for the treatment of atherogenesis.