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Diabetic cardiomyopathy (DCM) represents a common pathological state brought about by diabetes mellitus (DM). Patchouli alcohol (PatA) is known for its diverse advantageous effects, notably its anti-inflammatory properties and protective role against metabolic disorders. Despite this, the influence of PatA on DCM remains relatively unexplored. To explore the effect of PatA on diabetes-induced cardiac injury and dysfunction in mice, streptozotocin (STZ) was used to mimic type 1 diabetes in mice. Serological markers and echocardiography show that PatA treatment protects the heart against cardiomyopathy by controlling myocardial fibrosis but not by reducing hyperglycemia in diabetic mice. Discovery Studio 2017 software was used to perform reverse target screening of PatA, and we found that JAK2 may be a potential target of PatA. RNA-seq analysis of heart tissues revealed that PatA activity in the myocardium was primarily associated with the inflammatory fibrosis through the Janus tyrosine kinase 2 (JAK2)/signal transducer and activator of the transcription 3 (STAT3) pathway. In vitro, we also found that PatA alleviates high glucose (HG) + palmitic acid (PA)-induced fibrotic and inflammatory responses via inhibiting the JAK2/STAT3 signaling pathway in H9C2 cells. Our findings illustrate that PatA mitigates the effects of HG + PA- or STZ-induced cardiomyopathy by acting on the JAK2/STAT3 signaling pathway. These insights indicate that PatA could potentially serve as a therapeutic agent for DCM treatment. [ABSTRACT FROM AUTHOR]

Protein tyrosine kinases (RTKs) modulate a wide range of pathophysiological events in several non-malignant disorders, including diabetic complications. To find new targets driving the development of diabetic cardiomyopathy (DCM), we profiled an RTKs phosphorylation array in diabetic mouse hearts and identified increased phosphorylated fibroblast growth factor receptor 1 (p-FGFR1) levels in cardiomyocytes, indicating that FGFR1 may contribute to the pathogenesis of DCM. Using primary cardiomyocytes and H9C2 cell lines, we discovered that high-concentration glucose (HG) transactivates FGFR1 kinase domain through toll-like receptor 4 (TLR4) and c-Src, independent of FGF ligands. Knocking down the levels of either TLR4 or c-Src prevents HG-activated FGFR1 in cardiomyocytes. RNA-sequencing analysis indicates that the elevated FGFR1 activity induces pro-inflammatory responses via MAPKs–NF κ B signaling pathway in HG-challenged cardiomyocytes, which further results in fibrosis and hypertrophy. We then generated cardiomyocyte-specific FGFR1 knockout mice and showed that a lack of FGFR1 in cardiomyocytes prevents diabetes-induced cardiac inflammation and preserves cardiac function in mice. Pharmacological inhibition of FGFR1 by a selective inhibitor, AZD4547, also prevents cardiac inflammation, fibrosis, and dysfunction in both type 1 and type 2 diabetic mice. These studies have identified FGFR1 as a new player in driving DCM and support further testing of FGFR1 inhibitors for possible cardioprotective benefits. Hyperglycemia activates FGFR1 through TLR4 and c-Src axis in cardiomyopathy, which induces MAPKs-mediated NF κ B activation to increase inflammatory response and subsequent fibrosis and hypertrophy, driving the pathogenesis of DCM. [Display omitted] [ABSTRACT FROM AUTHOR]

Diabetes manifests as chronic inflammation and leads to the development diabetic cardiomyopathy (DCM). Targeting key proteins in inflammatory signaling may provide new therapy for DCM. In this study, the authors explore the pharmacological effects and mechanisms of Schisandrin B (Sch B), a natural compound with anti‐inflammatory activity against DCM. It is shown that Sch B prevents high‐level glucose (HG)‐induced hypertrophic and fibrotic responses in cultured cardiomyocytes. RNA sequencing and inflammatory qPCR microarray show that Sch B mainly affects myeloid differentiation primary response 88 (MyD88)‐dependent inflammatory gene expression in HG‐challenged cardiomyocytes. Further studies indicate that Sch B directly binds to and inhibits MyD88 activation, but does not alter MyD88‐independent Toll‐like receptor signaling in vivo and in vitro. Inhibiting or silencing MyD88 is associated with reduced levels of HG‐induced inflammatory cytokines and myocardial injuries in vitro. Treatment of type 1 and type 2 diabetic mice with Sch B protects heart function, reduces myocardial injuries, and decreases secretion of inflammatory cytokines. Cardiomyocyte‐specific MyD88 knockout also protects mice against cardiac inflammation and injury in type 1 diabetic mice. In conclusion, these studies show that cardiomyocyte MyD88 plays an apathogenetic role in DCM and Sch B specifically targets MyD88 to reduce inflammatory DCM. [ABSTRACT FROM AUTHOR]

Hyperglycemia activates toll-like receptor 4 (TLR4) to induce inflammation in diabetic cardiomyopathy (DCM). However, the mechanisms of TLR4 activation remain unclear. Here we examine the role of myeloid differentiation 2 (MD2), a co-receptor of TLR4, in high glucose (HG)- and diabetes-induced inflammatory cardiomyopathy. We show increased MD2 in heart tissues of diabetic mice and serum of human diabetic subjects. MD2 deficiency in mice inhibits TLR4 pathway activation, which correlates with reduced myocardial remodeling and improved cardiac function. Mechanistically, we show that HG induces extracellular advanced glycation end products (AGEs), which bind directly to MD2, leading to formation of AGEs-MD2-TLR4 complex and initiation of pro-inflammatory pathways. We further detect elevated AGE-MD2 complexes in heart tissues and serum of diabetic mice and human subjects with DCM. In summary, we uncover a new mechanism of HG-induced inflammatory responses and myocardial injury, in which AGE products directly bind MD2 to drive inflammatory DCM. The mechanisms underlying cardiac inflammation in diabetic cardiomyopathy are incompletely understood. Here the authors show that advanced glycation end products bind to the TLR4 co-receptor MD2 initiating pro-inflammatory pathways. [ABSTRACT FROM AUTHOR]

Abstract Diabetic cardiomyopathy (DCM) is a common and severe complication of diabetes. A multitude of factors are involved in the pathogenesis of DCM including chronic inflammation and oxidative stress. We have recently shown that compound LF10 prevents inflammatory responses in an animal model of lung injury. In the present study, we explored the protective effects and mechanism of LF10 against DCM using a mouse model of streptozotocin-induced diabetes and high glucose (HG)-challenged cultured cardiomyocytes. We show that LF10 suppressed diabetes-induced cardiomyocyte hypertrophy and fibrosis, which was accompanied by preservation of cardiac function in mice. Mechanistically, LF10 prevented increases in the levels of pro-inflammatory molecules and oxidative stress under in vitro and in vivo diabetic conditions. Moreover, LF10 restored HG-downregulated sirtuin 1 (SIRT1) in cardiomyocytes and prevented HG-induced activation of MAPKs. Using specific small-molecule regulators, we found that SIRT1 was an upstream signal of MAPKs. In conclusion, LF10 inhibited ROS and MAPKs-mediated inflammation by restoring SIRT1, and prevented development of DCM. LF10 targeted both oxidative stress and inflammation, two tightly interconnected pathogenic pathways, which makes LF10 a highly advantageous therapeutic drug potential. Highlights • LF10 suppressed diabetes-induced cardiomyocyte hypertrophy and fibrosis. • LF10 prevented increases of pro-inflammatory molecules and oxidative stress. • LF10 induced blockade of ROS and MAPKs-mediated inflammation by restoring SIRT1. • LF10 could be a highly advantageous therapeutic drug potential. [ABSTRACT FROM AUTHOR]

Ss. [Display omitted] Hyperglycemia-associated inflammation contributes to diabetic cardiomyopathy. Myeloid differentiation primary-response protein 88 (MyD88) is an adapter protein of many Toll-like receptors (TLRs) and is recruited to TLRs to initiate inflammatory response in endotoxin-activated innate immunity. However, the role of MyD88 in diabetic cardiomyopathy is unknown. We examined the role and mechanism of MyD88 in inflammatory heart injuries in diabetes and identified MyD88 as a potential target for the treatment of diabetic cardiomyopathy. In this study, we first found that MyD88 expression was increased in cardiomyocytes of diabetic mouse hearts. In cultured cardiomyocytes, MyD88 inhibition either by siRNA or by small-molecular inhibitor LM8 markedly blocked TLR4-MyD88 complex formation, reduced pro-inflammatory mitogen-activated protein kinases/nuclear factor-κB (MAPKs/NF-κB) cascade activation and decreased pro-inflammatory cytokine expression under high glucose condition. Moreover, pharmacologic inhibition of MyD88 by LM8 showed significantly anti-inflammatory, anti-hypertrophic and anti-fibrotic effects in the hearts of both type 1 and type 2 diabetic mice. These beneficial effects of MyD88 inhibition were correlated to the reduced activation of TLR4-MyD88-MAPKs/NF-κB signaling pathways in the hearts. Taken together, MyD88 in cardiomyocytes mediates diabetes-induced cardiac inflammatory injuries and pharmacological inhibition of MyD88 shows significantly cardioprotective effects, indicating MyD88 as a potential therapeutic target for diabetic cardiomyopathy. [ABSTRACT FROM AUTHOR]

Background: Diabetes mellitus is a well-known risk factor for the development of heart failure. Inflammation and oxidative stress play a key role in the development of diabetic cardiomyopathy (DCM), and this nexus represents an attractive target to combat this disease. Naturally occurring flavonoid luteolin exhibits both anti-inflammatory and antioxidant activities in various systems.Hypothesis/purpose: In this study, we aimed to investigate potential cardioprotective effects of luteolin in cultured cardiomyocytes and in mice with type 1 diabetes.Methods: C57BL/6 mice were intraperitoneal injection of streptozotocin (STZ) to induce DCM. High glucose (HG) was used to induce H9C2 cells injury in vitro. Cardiac fibrosis, hypertrophy, inflammation and oxidative stress were studied both in vitro and in vivo.Results: Our studies show that luteolin significantly reduces HG-induced inflammatory phenotype and oxidative stress in H9C2 cardiomyocytes. We found that the mechanisms involved inhibition of nuclear factor-kappa B (NF-κB) pathway and the activation of antioxidant nuclear factor-erythroid 2 related factor 2 (Nrf2) signaling pathway. Modulation of these pathways resulted in reduced expression of matrix proteins and cellular hypertrophy. Luteolin also prevented cardiac fibrosis, hypertrophy, and dysfunction in STZ-induced diabetic mice. These readouts were also associated with reduced levels of inflammatory cytokines and oxidative stress biomarkers.Conclusion: Our results indicate that luteolin protects heart tissues in STZ-induced diabetic mice through modulating Nrf2-mediated oxidative stress and NF-κB-mediated inflammatory responses. These findings suggest that luteolin may be a potential therapeutic agent for DCM. [ABSTRACT FROM AUTHOR]

Heart failure (HF) is one of the major causes of death among diabetic patients. Although studies have shown that curcumin analog C66 can remarkably relieve diabetes-associated cardiovascular and kidney complications, the role of SJ-12, SJ-12, a novel curcumin analog, in diabetic cardiomyopathy and its molecular targets are unknown. 7-week-old male C57BL/6 mice were intraperitoneally injected with single streptozotocin (STZ) (160 mg/kg) to develop diabetic cardiomyopathy (DCM). The diabetic mice were then treated with SJ-12 via gavage for two months. Body weight, fast blood glucose, cardiac utrasonography, myocardial injury markers, pathological morphology of the heart, hypertrophic and fibrotic markers were assessed. The potential target of SJ-12 was evaluated via RNA-sequencing analysis. The O-GlcNAcylation levels of SP1 were detected via immunoprecipitation. SJ-12 effectively suppressed myocardial hypertrophy and fibrosis, thereby preventing heart dysfunction in mice with STZ-induced heart failure. RNA-sequencing analysis revealed that SJ-12 exerted its therapeutic effects through the modulation of the calcium signaling pathway. Furthermore, SJ-12 reduced the O-GlcNAcylation levels of SP1 by inhibiting O-linked N -acetylglucosamine transferase (OGT). Also, SJ-12 stabilized Sarcoplasmic/Endoplasmic Reticulum Calcium ATPase 2a (SERCA2a), a crucial regulator of calcium homeostasis, thus reducing hypertrophy and fibrosis in mouse hearts and cultured cardiomyocytes. However, the anti-fibrotic effects of SJ-12 were not detected in SERCA2a or OGT-silenced cardiomyocytes, indicating that SJ-12 can prevent DCM by targeting OGT-dependent O-GlcNAcylation of SP1.These findings indicate that SJ-12 can exert cardioprotective effects in STZ-induced mice by reducing the O-GlcNAcylation levels of SP1, thus stabilizing SERCA2a and reducing myocardial fibrosis and hypertrophy. Therefore, SJ-12 can be used for the treatment of diabetic cardiomyopathy. [Display omitted] • Compound SJ-12 alleviates cardiac dysfunction, hypertrophy, and fibrosis in DCM. • SJ-12 increases the level of SERCA2a, a crucial regulator of calcium homeostasis, thus playing a protective role in DCM. • Mechanistically, the cardiac protection effect of SJ-12 was targeting OGT-regulated O-GlcNAc-Sp1/SERCA2a axis. [ABSTRACT FROM AUTHOR]

Diabetic cardiomyopathy (DCM) is a pathophysiological condition triggered by diabetes mellitus and can lead to heart failure. Doublecortin-like kinase protein 1 (DCLK1) is a multifunctional protein kinase involved in the regulation of cell proliferation, differentiation, survival, and migration. Current studies on DCLK1 mainly focus on cancer development; however, its role in non-tumor diseases such as DCM is yet to be deciphered. Our analysis revealed that DCLK1 was upregulated in cardiomyocytes of streptozotocin (STZ)-induced type 1 diabetic mouse, suggesting a correlation between DCLK1 and DCM progression. It was further demonstrated that either cardiomyocyte-specific DCLK1 knockout or pharmacological DCLK1 inhibitor DCLK1-IN-1 significantly alleviated cardiac hypertrophy and fibrosis in STZ-induced diabetic mice. RNA-seq analysis of heart tissues revealed that DCLK1 regulated the nuclear factor kappa B (NF-κB)-mediated inflammatory response in DCM. In vitro , DCLK1 activated NF-κB and the inflammatory response by inducing the IKKβ phosphorylation in high-concentration glucose (HG)-challenged cardiomyocytes. DCLK1-IN-1 also prevented HG-induced IKKβ/NF-κB activation and inflammatory injuries in cardiomyocytes. In conclusion, this study highlights the novel role of cardiomyocyte DCLK1 in regulating IKKβ/NF-κB, which aggravates inflammation to promote the pathogenesis of DCM. DCLK1 may serve as a new target for DCM treatment. [Display omitted] • DCLK1 is upregulated in the heart tissues of STZ-induced diabetic mice. • Either DCLK1 deletion in cardiomyocytes or pharmacological inhibition of DCLK1 attenuated DCM in diabetic mice. • DCLK1 regulates NF-κB pathway to aggravate inflammation in cardiomyocytes. • DCLK1 could be a novel therapeutic target for the treatment of inflammatory DCM. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chronic inflammation contributes to the development of DCM, • A novel MyD88 inhibitor, c17, has been shown to exhibit anti-inflammatory effect. • Compound c17 improved heart dysfunction, hypertrophy, and fibrosis in DCM. • The cardiac protection effect of c17 was mediated via suppressing the interaction of TLR4 and MyD88. • Compound c17 could be a potential candidate for DCM. Diabetic cardiomyopathy (DCM) is a common complication of diabetes mellitus and is associated with increased morbidity and mortality due to cardiac dysfunction. Chronic inflammation plays a significant role in the development of DCM, making it a promising target for novel pharmacological strategies. Our previous study has synthesized a novel compound, c17, which exhibited strong anti-inflammatory activity by specifically targeting to myeloid differentiation primary response 88 (MyD88). In this study, we evaluated the therapeutic effect of c17 in DCM. The small molecular selective MyD88 inhibitor, c17, was used to evaluate the effect of MyD88 on DCM in both high concentration of glucose- and palmitic acid-stimulated macrophages and streptozotocin (STZ)-induced type 1 diabetes mellitus (T1DM) mice. The treatment of c17 in T1DM mice resulted in improved heart function and reduced cardiac hypertrophy, inflammation and fibrogenesis. RNA sequencing analysis of the heart tissues revealed that c17 effectively suppressed the inflammatory response by regulating the MyD88-dependent pathway. Co-immunoprecipitation experiments further confirmed that c17 disrupted the interaction between MyD88 and Toll-like receptor 4 (TLR4), consequently inhibiting downstream NF-κB activation. In vitro studies demonstrated that c17 exhibited similar anti-inflammatory activity by targeting MyD88 in macrophages, which are the primary regulators of cardiac inflammation. Furthermore, conditioned medium derived from c17-treated macrophages showed reduced capacity to induce hypertrophy, pro-fibrotic reactions, and secondary inflammation in cardiomyocytes. In conclusion, the small-molecule MyD88 inhibitor, c17, effectively combated the inflammatory DCM, therefore could be a potential candidate for the treatment of this disease. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases are the primary cause of mortality in patients with diabetes and obesity. Hyperglycemia and hyperlipidemia in diabetes alters cardiac function, which is associated with broader cellular processes such as aberrant inflammatory signaling. Recent studies have shown that a pattern recognition receptor called Dectin-1, expressed on macrophages, mediates pro-inflammatory responses in innate immunity. In the present study, we examined the role of Dectin-1 in the pathogenesis of diabetic cardiomyopathy. We observed increased Dectin-1 expression in heart tissues of diabetic mice and localized the source to macrophages. We then investigated the cardiac function in Dectin-1-deficient mice with STZ-induced type 1 diabetes and high-fat-diet-induced type 2 diabetes. Our results show that Dectin-1 deficient mice are protected against diabetes-induced cardiac dysfunction, cardiomyocyte hypertrophy, tissue fibrosis, and inflammation. Mechanistically, our studies show that Dectin-1 is important for cell activation and induction of inflammatory cytokines in high-concentration glucose and palmitate acid (HG + PA)-challenged macrophages. Deficiency of Dectin-1 generate fewer paracrine inflammatory factors capable of causing cardiomyocyte hypertrophy and fibrotic responses in cardiac fibroblasts. In conclusion, this study provides evidence that Dectin-1 mediates diabetes-induced cardiomyopathy through regulating inflammation. Dectin-1 may be a potential target to combat diabetic cardiomyopathy. [Display omitted] • Dectin-1 is upregulated in cardiac tissue of diabetic mice. • Dectin-1 aggravates diabetic cardiomyopathy via regulating Syk/NF-κB activation and cardiac inflammatory response. • Dectin-1-mediated cytokines in macrophages promote hypertrophy in cardiomyocytes and fibrosis in cardiac fibroblasts. • Targeting Dectin-1 may offer new promises in diabetes-induced cardiac injuries. [ABSTRACT FROM AUTHOR]

Cardiac inflammation is an important pathological process in diabetic cardiomyopathy (DCM). Curcumin is a natural compound found in the rhizome of Curcuma longa and has been shown to possess multifunctional bioactivities. In the present study, we identified a new curcumin-derived compound, JM-2, and investigated its therapeutic effects against DCM in mouse models of streptozotocin-induced type 1 diabetes mellitus (T1DM) and HFD-induced type 2 diabetes (T2DM). Treatment with JM-2 (10 mg/kg) prevented cardiac functional and structural deficits effectively and reduced cardiac inflammation and fibrosis. JM-2 administration attenuated DCM by inhibiting nuclear factor kappa-B (NF-κB) activation in the heart of both models. In addition, treatment with JM-2 completely prevented the increase in proinflammatory factors and macrophage infiltration in T1DM and T2DM mice. RNA-seq analysis showed that the anti-inflammatory activity of JM-2 was associated with the inhibition of NF-κB activation. In vitro, JM-2 suppressed high glucose (HG)-induced myocardial hypertrophy and fibrosis in H9c2 cells, accompanied by inhibition of HG-induced NF-κB activation. Collectively, our results showed that JM-2, a new curcumin analog, provides strong protection against DCM via inhibition of the NF-κB-mediated inflammation. In summary, our data suggest that the curcumin analog JM-2 may be a potential therapeutic agent for DCM. [Display omitted] • We designed a new curcumin-derived compound, JM-2, which exhibits anti-inflammation effects. • JM-2 attenuates heart injury, inflammation and fibrosis both in T1DM and T2DM. • JM-2 could attenuate diabetic cardiomyopathy via inhibiting NF-κB pathway in both vitro and vivo. • JM-2 may serve as a potential therapeutic drug for DCM. [ABSTRACT FROM AUTHOR]