Time-Released Black Phosphorus Hydrogel Accelerates Myocardial Repairing through Antioxidant and Motivates Macrophage Polarization Properties.

The improvement of the myocardial microenvironment largely determines the prognosis of myocardial infarction (MI). After MI, early removal of excessive reactive oxygen species (ROS) in the microenvironment can alleviate oxidative stress injury and promote M2 phenotype polarization of macrophages, which is important for advocating myocardial repair. In this study, we combined traditional natural hydrogel materials chitosan (CS) and gelatin (Gel) to encapsulate polydopamine-modified black phosphorus nanosheets (BP@PDA). We designed an injectable composite gel (CS-Gel-BP@PDA) with a time-released ability to achieve in situ sustained-release BP@PDA in the area of MI. Utilizing the inflammation inhibition ability of CS-Gel itself and the high reactive activity of BP@PDA with ROS, continuous improvement of infarct microenvironment and myocardial repair were achieved. The studies in vivo revealed that, compared with the saline group, CS-Gel-BP@PDA group had alleviated myocardial fibrosis and infarct size and importantly improved cardiac function. Immunofluorescence results showed that the ROS level and inflammatory response in the microenvironment of the CS-Gel-BP@PDA group were decreased. In conclusion, our study demonstrated the time-released ability, antioxidative stress activity and macrophage polarization modulation of the novel composite hydrogel CS-Gel-BP@PDA, which provides inspiration for novel therapeutic modalities for MI.

Pterostilbene attenuates heart failure by inhibiting myocardial ferroptosis through SIRT1/GSK-3ß/GPX4 signaling pathway.

Sustained myocardial injury due to hypertension and diabetes mellitus leads to production of endogenous reactive oxygen species (ROS) and insufficient myocardial antioxidant capacity, increasing the risk of cardiomyocyte ferroptosis. Ferroptosis is a nonapoptotic form of cell death driven by unrestricted lipid peroxidation. Dysfunction of the glutathione peroxidase 4 (GPX4) antioxidant system also plays an important role in ferroptosis. Cardiomyocyte ferroptosis ultimately leads to myocardial deterioration, such as inflammation, fibrosis, and cardiac remodeling, resulting in structural and functional changes. Pterostilbene (PTS), a demethylated derivative of resveratrol, exhibits strong anti-inflammatory and antioxidative activities. In this study, we used in vitro experiments to explore ferroptosis induced by angiotensin II (Ang II) of primary cardiac myocytes (CMs) and in vivo experiments to prepare a transverse aortic constriction (TAC)-induced cardiac dysfunction mouse model. PTS can significantly ameliorate Ang II-induced cardiomyocyte ferroptosis in vitro and reduce cardiac remodeling, while improving cardiac function in mice after TAC in vivo. Further mechanistic investigations revealed that PTS exerts its protective effect through the SIRT1/GSK-3ß/GPX4 pathway. After siRNA-mediated knockdown of SIRT1 or GPX4 in CMs, the protective effects of PTS on cardiomyocytes were abolished. This study provides important theoretical support for the potential of PTS to attenuate pathological cardiac remodeling and heart failure and provides a preliminary exploration of the molecular pathways involved in its protective mechanism.

No evidence of coronary plaque stabilization by allopurinol in patients with acute coronary syndrome.

BACKGROUND: Allopurinol, a xanthine inhibitor that lowers uric acid concentration, has been proven to reduce inflammation and oxidative stress in patients with cardiovascular disease. However, it is unknown whether these beneficial effects translate into favorable plaque modification in acute coronary syndromes (ACS). This study aimed to investigate whether allopurinol could improve coronary plaque stabilization using coronary computed tomography angiography (CCTA). METHODS: This was a prospective, single-center, randomized, double-blind clinical trial began in March 2019. A total of 162 ACS patients aged 18-80 years with a blood level of high-sensitivity C-reactive protein (hsCRP) â€‹> â€‹2 â€‹mg/L were included. The subjects were randomly assigned in a 1:1 ratio to receive either allopurinol sustained-release capsules (at a dose of 0.25 â€‹g once daily) or placebo for 12 months. The plaque analysis was performed at CCTA. The primary efficacy endpoint was the change in low-attenuation plaque volume (LAPV) from baseline to the 12-month follow-up. RESULTS: Among 162 patients, 54 in allopurinol group and 51 in placebo group completed the study. The median follow-up duration was 14 months in both groups. Compared with placebo, allopurinol therapy did not significantly alter LAPV (-13.4 â€‹± â€‹3.7 â€‹% vs. -17.8 â€‹± â€‹3.6 â€‹%, p â€‹= â€‹0.390), intermediate attenuation plaque volume (-16.1 â€‹± â€‹3.0 â€‹% vs. -16.2 â€‹± â€‹2.9 â€‹%, p â€‹= â€‹0.992), dense calcified plaque volume (12.2 â€‹± â€‹13.7 â€‹% vs. 9.7 â€‹± â€‹13.0 â€‹%, p â€‹= â€‹0.894), total atheroma volume (-15.2 â€‹± â€‹3.2 â€‹% vs. -16.4 â€‹± â€‹3.1 â€‹%, p â€‹= â€‹0.785), remodeling index (2.0 â€‹± â€‹3.9 â€‹% vs. 5.4 â€‹± â€‹3.8 â€‹%, p â€‹= â€‹0.536) or hsCRP levels (-73.6 [-91.6-17.9] % vs. -81.2 [-95.4-47.7] %, p â€‹= â€‹0.286). CONCLUSIONS: Our findings suggest that allopurinol does not improve atherosclerotic plaque stability or inflammation in ACS.

Pharmacological activation of GPX4 ameliorates doxorubicin-induced cardiomyopathy.

Due to the cardiotoxicity of doxorubicin (DOX), its clinical application is limited. Lipid peroxidation caused by excessive ferrous iron is believed to be a key molecular mechanism of DOX-induced cardiomyopathy (DIC). Dexrazoxane (DXZ), an iron chelator, is the only drug approved by the FDA for reducing DIC, but it has many side effects and cannot be used as a preventive drug in clinical practice. Single-nucleus RNA sequencing (snRNA-seq) analysis identified myocardial and epithelial cells that are susceptible to DOX-induced ferroptosis. The glutathione peroxidase 4 (GPX4) activator selenomethione (SeMet) significantly reduced polyunsaturated fatty acids (PUFAs) and oxidized lipid levels in vitro. Consistently, SeMet significantly decreased DOX-induced lipid peroxidation in H9C2 cells and mortality in C57BL/6 mice compared to DXZ, ferrostatin-1, and normal saline. SeMet can effectively reduce serum markers of cardiac injury in C57BL/6 mice and breast cancer patients. Depletion of the GPX4 gene in C57BL/6 mice resulted in an increase in polyunsaturated fatty acid (PUFA) levels and eliminated the protective effect of SeMet against DIC. Notably, SeMet exerted antitumor effects on breast cancer models with DOX while providing cardiac protection for the same animal without detectable toxicities. These findings suggest that pharmacological activation of GPX4 is a valuable and promising strategy for preventing the cardiotoxicity of doxorubicin.

Application of biomedical materials in the diagnosis and treatment of myocardial infarction.

Myocardial infarction (MI) is a cardiovascular emergency and the leading cause of death worldwide. Inflammatory and immune responses are initiated immediately after MI, leading to myocardial death, scarring, and ventricular remodeling. Current therapeutic approaches emphasize early restoration of ischemic myocardial reperfusion, but there is no effective treatment for the pathological changes of infarction. Biomedical materials development has brought new hope for MI diagnosis and treatment. Biomedical materials, such as cardiac patches, hydrogels, nano biomaterials, and artificial blood vessels, have played an irreplaceable role in MI diagnosis and treatment. They improve the accuracy and efficacy of MI diagnosis and offer further possibilities for reducing inflammation, immunomodulation, inhibiting fibrosis, and cardiac regeneration. This review focuses on the advances in biomedical materials applications in MI diagnosis and treatment. The current studies are outlined in terms of mechanisms of action and effects. It is addressed how biomedical materials application can lessen myocardial damage, encourage angiogenesis, and enhance heart function. Their clinical transformation value and application prospect are discussed.

Overexpression of LOX-1 in hepatocytes protects vascular smooth muscle cells from phenotype transformation and wire injury induced carotid neoatherosclerosis through ALOX15.

Neoatherosclerosis (NA), the main pathological basis of late stent failure, is the main limitation of interventional therapy. However, the specific pathogenesis and treatment remain unclear. In vivo, NA model was established by carotid wire injury and high-fat feeding in ApoE-/- mice. Oxidized low-density lipoprotein receptor-1/lectin-like oxidized low-density lipoprotein receptor-1 (OLR1/LOX-1), a specific receptor for oxidized low-density lipoprotein (ox-LDL), was specifically ectopically overexpressed in hepatocytes by portal vein injection of adeno-associated serotype 8 (AAV8)-thyroid binding globulin (TBG)-Olr1 and the protective effect against NA was examined. In vitro, LOX-1 was overexpressed on HHL5 using lentivirus (LV)-OLR1 and the vascular smooth muscle cells (VSMCs)-HHL5 indirect co-culture system was established to examine its protective effect on VSMCs and the molecular mechanism. Functionally, we found that specific ectopic overexpression of LOX-1 by hepatocytes competitively engulfed and metabolized ox-LDL, alleviating its resulting phenotypic transformation of VSMCs including migration, downregulation of contractile shape markers (smooth muscle α-actin (SMαA) and smooth muscle-22α (SM22α)), and upregulation of proliferative/migratory shape markers (osteopontin (OPN) and Vimentin) as well as foaminess and apoptosis, thereby alleviating NA, which independent of low-density lipoprotein (LDL) lowering treatment (evolocumab, a monoclonal antibody to proprotein convertase subtilisin/kexin type 9 (PCSK9)). Mechanistically, we found that overexpression of LOX-1 in hepatocytes competitively engulfed and metabolized ox-LDL through upregulation of arachidonate-15-lipoxygenase (ALOX15), which further upregulated scavenger receptor class B type I (SRBI) and ATP-binding cassette transporter A1 (ABCA1). In conclusion, the overexpression of LOX-1 in liver protects VSMCs from phenotypic transformation and wire injury induced carotid neoatherosclerosis through ALOX15.

Selenium and Selenoproteins in Health.

Selenium is a trace mineral that is essential for health. After being obtained from food and taken up by the liver, selenium performs various physiological functions in the body in the form of selenoproteins, which are best known for their redox activity and anti-inflammatory properties. Selenium stimulates the activation of immune cells and is important for the activation of the immune system. Selenium is also essential for the maintenance of brain function. Selenium supplements can regulate lipid metabolism, cell apoptosis, and autophagy, and have displayed significant alleviating effects in most cardiovascular diseases. However, the effect of increased selenium intake on the risk of cancer remains unclear. Elevated serum selenium levels are associated with an increased risk of type 2 diabetes, and this relationship is complex and nonlinear. Selenium supplementation seems beneficial to some extent; however, existing studies have not fully explained the influence of selenium on various diseases. Further, more intervention trials are needed to verify the beneficial or harmful effects of selenium supplementation in various diseases.

MicroRNA-146a Promotes Embryonic Stem Cell Differentiation towards Vascular Smooth Muscle Cells through Regulation of Kruppel-like Factor 4.

OBJECTIVE: Vascular smooth muscle cell (VSMC) differentiation from stem cells is one source of the increasing number of VSMCs that are involved in vascular remodeling-related diseases such as hypertension, atherosclerosis, and restenosis. MicroRNA-146a (miR-146a) has been proven to be involved in cell proliferation, migration, and tumor metabolism. However, little is known about the functional role of miR-146a in VSMC differentiation from embryonic stem cells (ESCs). This study aimed to determine the role of miR-146a in VSMC differentiation from ESCs. METHODS: Mouse ESCs were differentiated into VSMCs, and the cell extracts were analyzed by Western blotting and RT-qPCR. In addition, luciferase reporter assays using ESCs transfected with miR-146a/mimic and plasmids were performed. Finally, C57BL/6J female mice were injected with mimic or miR-146a-overexpressing ESCs, and immunohistochemistry, Western blotting, and RT-qPCR assays were carried out on tissue samples from these mice. RESULTS: miR-146a was significantly upregulated during VSMC differentiation, accompanied with the VSMC-specific marker genes smooth muscle-alpha-actin (SMαA), smooth muscle 22 (SM22), smooth muscle myosin heavy chain (SMMHC), and h1-calponin. Furthermore, overexpression of miR-146a enhanced the differentiation process in vitro and in vivo. Concurrently, the expression of Kruppel-like factor 4 (KLF4), predicted as one of the top targets of miR-146a, was sharply decreased in miR-146a-overexpressing ESCs. Importantly, inhibiting KLF4 expression enhanced the VSMC-specific gene expression induced by miR-146a overexpression in differentiating ESCs. In addition, miR-146a upregulated the mRNA expression levels and transcriptional activity of VSMC differentiation-related transcription factors, including serum response factor (SRF) and myocyte enhancer factor 2c (MEF-2c). CONCLUSION: Our data support that miR-146a promotes ESC-VSMC differentiation through regulating KLF4 and modulating the transcription factor activity of VSMCs.

Case report: Spontaneous closure of ventricular pseudoaneurysm post-acute myocardial infarction with non-surgical therapy.

Left ventricle (LV) pseudoaneurysm is a rare disorder post-acute myocardial infarction (AMI). Resection or closure of the pseudoaneurysm by surgery is recommended due to the high propensity of pseudoaneurysm rupture while surgery has also high risks. Conservative therapy could be acceptable in small pseudoaneurysms or patients with high surgical risks. Nevertheless, the risk evaluation and grasp of indication are not clear. This case reported an acute cyst-like LV pseudoaneurysm formation post-AMI-induced myocardial free wall rupture (MFWR), and the patient recovered with spontaneous closure of the fissure and shrinkage of the LV pseudoaneurysm through non-surgical therapy. Based on the observations in the echocardiogram, we proposed that intermittent closing of the fissure and interruption of the blood flow between the LV and the pseudoaneurysm due to LV contraction alleviated stress change on the pseudoaneurysm. The narrow fissure, small pseudoaneurysm, and intermittently interrupted blood flow that benefit fissure healing and pseudoaneurysm stabilization could indicate the prognosis of this patient. Drugs like ß-blocker that decreased the stress on the pseudoaneurysm also led to the risk reduction of pseudoaneurysm rupture. To our knowledge, this is the first case that reports a spontaneous closure of LV pseudoaneurysm. The size of the fissure and the pseudoaneurysm, as well as the corresponding hemodynamic state, could be valuable to evaluate the risk and prognosis of the pseudoaneurysm. Optimized medical management was also helpful to pseudoaneurysm stabilization.

Safety Assessment of Microcatheter-Protected Rotational Atherectomy with the Double Guiding Catheter Technique for Severely Calcified Left Main Bifurcation.

Background: Rotational atherectomy (RA) is a tool for calcium modification, but there is a risk of losing the side branch in left main coronary artery (LM) bifurcation lesions, resulting in disastrous consequences. Microcatheter-protected RA with the double guiding catheter (GC) technique for severely calcified LM bifurcations has been described previously, but its safety warrants further investigation. Methods: Various sizes of coronary calcification vascular simulators were utilized to model calcified LM bifurcation lesions for RA in in vitro. The damage to the side branch protective microcatheters and guidewires was accessed after microcatheter-protected RA with the double GC technique. In clinical practice, microcatheter-protected RA with the double GC technique was carried out in two patients. Results: In vitro, none of the protective microcatheters or guidewires were completely fractured, although the majority of them were damaged to varying degrees. In clinical practice, we successfully carried out two cases of percutaneous coronary intervention for severely calcified LM bifurcation with microcatheter-protected RA using the double GC technique. Conclusion: RA of severely calcified LM bifurcation lesions may be successfully performed using microcatheter-protected RA with the double GC technique, potentially reducing the risk of side branch occlusion. Since majority of protective microcatheters or guidewires were damaged, there was still some risk, and it is recommended to use this technique only in highly selected patient population of severely calcified true (Medina 1, 1, 1) LM bifurcations.

Reducing the Damage of Ox-LDL/LOX-1 Pathway to Vascular Endothelial Barrier Can Inhibit Atherosclerosis.

Aim: The destruction of the vascular endothelial barrier mediated by Ox-LDL is the initial link to atherosclerosis. Here, we aimed to determine whether the immunological intervention with Ox-ApoB polypeptide fragment (Ox-ApoB-PF) can block the deposition of Ox-LDL in vascular endothelial cells through LOX-1 receptors, thereby protecting the barrier function and survival status of vascular endothelial cells and inhibiting the progression of atherosclerosis. Methods and Results: In order to determine the harm of Ox-LDL to vascular endothelial cells and the protective effect of immune intervention with Ox-ApoB-PF, we conducted a series of corresponding experiments in vitro and in vivo. The in vitro results showed that Ox-LDL can activate endothelial cell apoptosis pathway; reduce the expression of endothelial junction proteins; affect the migration, deformation, and forming ability; and ultimately destroy the vascular endothelial barrier function. The increased permeability of endothelial cells led to a sharp increase in the phagocytosis of Ox-LDL by macrophages under the endothelial layer. Meanwhile, Ox-LDL stimulation induced a significant upregulation of LOX-1 in endothelial cells and increased the expression of endothelial cell chemokines and adhesion factors. Ox-ApoB-PF antibodies can significantly reduce the abovementioned harmful effects. The in vivo results showed that active immune intervention through Ox-ApoB-PF can protect the endothelial barrier function; reduce macrophage deposition and the inflammatory response in plaques; alleviate lipid deposition in the plaques, as well as apoptosis and necrosis; and increase the ability of liver macrophages to clear Ox-LDL. Eventually, the progression of plaque and the formation of necrotic cores in plaques can be inhibited. Conclusions: An Ox-ApoB-PF antibody may protect the endothelial cell physiological function and survival status by blocking the combination of Ox-LDL/LOX-1 in vascular endothelial cells. Immune intervention with Ox-ApoB-PF inhibits the occurrence and development of atherosclerotic lesions by protecting the vascular endothelial barrier function.

The LOX-1 receptor ectopically expressed in the liver alleviates atherosclerosis by clearing Ox-LDL from the circulation.

OBJECTIVE: Oxidized Low-Density-Lipoprotein (Ox-LDL) is the core factor in the development of atherosclerosis. However, there are few therapies aimed at eliminating Ox-LDL. Here in this study, we investigate whether the ectopically expression of the lectin-like oxidized low density lipoprotein receptor (LOX-1) in the liver could lead to the elimination of circulating Ox-LDL and prevent the deposition in the vascular wall, thereby alleviating the progression of atherosclerosis. METHODS: Apolipoprotein E-deficient (ApoE-/-) mice were randomly divided into three groups, the control group, the AAV8-TBG-eGFP group (eGFP group) and AAV8-TBG-LOX-1 group (LOX-1 group). In the LOX-1 group, mice received an injection of virus dilution AAV8-TBG-LOX-1 (1.16 × 1011 virus genome (v.g)/animal/100 µl). The mice in the control group and eGFP group received the same amount of sterile saline and AAV8-TBG-eGFP virus dilution injections. The expression of LOX-1 in the liver was detected by immunofluorescent, western blot and immunohistochemistry. The safety of the virus was assessed by hematoxylin-eosin (H&E) staining, blood biochemical analyses and immunofluorescent. The function of LOX-1 in the liver was detected by the co-localization of LOX-1 and Dil-labeled Ox-LDL (Dil-Ox-LDL) under laser scanning confocal microscope. The extent of Ox-LDL in plasma was detected by ELISA. Changes in blood lipids were assessed through blood biochemical analysis. The progression of atherosclerotic lesions was detected by Oil red O staining. And the expression of Vascular Cell Adhesion Molecule-1 (VCAM-1) in endothelial cells and the extent and migration of macrophages in atherosclerotic plaque were detected by immunofluorescence staining. The protein expression in liver was assessed by qRT-PCR and western blot. RESULTS: The expression of LOX-1 was stable in liver within 4 weeks. Ectopically expressed LOX-1 in the liver phagocytosed and degraded Ox-LDL and reduced Ox-LDL from circulation but did not have a significant effect on blood lipid levels. After the expression of LOX-1 in liver, Ox-LDL can be cleared by the hepatocytes, thereby reducing VCAM-1 expression in vascular endothelium and the migration of macrophages in plaques, and eventually alleviating the progression of atherosclerosis. Functional expression of LOX-1 in hepatocytes may facilitate the metabolic clearance of Ox-LDL by upregulating the expression of ATP-binding cassette G5 and G8 (ABCG5/G8), which is the primary neutral sterol transporter in hepatobiliary and transintestinal cholesterol excretion. CONCLUSION: Ectopic liver-specific expression of LOX-1 receptor alleviates the progression of atherosclerosis by clearing Ox-LDL from circulation.

Autophagy in Atherosclerotic Plaque Cells: Targeting NLRP3 Inflammasome for Self-Rescue.

Atherosclerosis (AS) is a lipid-driven disorder of the artery intima characterized by the equilibrium between inflammatory and regressive processes. A protein complex called NLRP3 inflammasome is involved in the release of mature interleukin-1ß (IL-1ß), which is connected to the initiation and progression of atherosclerosis. Autophagy, which includes macroautophagy, chaperone-mediated autophagy (CMA), and microautophagy, is generally recognized as the process by which cells transfer their constituents to lysosomes for digestion. Recent studies have suggested a connection between vascular inflammation and autophagy. This review summarizes the most recent studies and the underlying mechanisms associated with different autophagic pathways and NLRP3 inflammasomes in vascular inflammation, aiming to provide additional evidence for atherosclerosis research.

Elimination of Ox-LDL through the liver inhibits advanced atherosclerotic plaque progression.

Aim: In the late stage of atherosclerosis, the endothelial barrier of plaque is destroyed. The rapid deposition of oxidized lipids in the circulation leads to migration of numerous smooth muscle cells and macrophages, as well as foaming necrosis. The plaque progresses rapidly, and vulnerable plaques can easily induce adverse cardiovascular events. Here, we take the principle of gene editing to transfer the liver to express the LOX-1 receptor which is more sensitive to Ox-LDL by using AAV8 containing a liver-specific promoter. In this way, we want to explore whether the progress of advanced atherosclerosis and the stability of advanced plaque can be improved when the liver continues to clear Ox-LDL from the circulation. Methods and Results: In order to explore the effect of the physiological and continuous elimination of Ox-LDL through the liver on advanced atherosclerosis, we chose ApoE-/- mice in high-fat diet for 20 weeks. After 16 weeks of high-fat diet, the baseline group was sacrificed and the specimens were collected. The virus group and the control group were injected with the same amount of virus dilution and normal saline through the tail vein, and continued to feed until 20 weeks of high-fat diet, and then sacrificed to collect specimens. The results showed that LOX-1 was ectopically and functionally expressed in the liver as an Ox-LDL receptor, reducing the content of it in circulation. Compared with the control group, the degree of plaque progression in the virus group was significantly reduced, similar to the baseline group, the plaque necrosis core decreased, and the collagen fiber content increased. In addition, there are more contractile smooth muscle cells in the plaques of the virus group instead of synthetic ones, and the content of macrophages was also reduced. These data suggested that the virus group mice have greatly increased advanced plaque stability compared with the control group mice. Conclusions: Due to the destruction of endothelial barrier in advanced plaques, rapid deposition of Ox-LDL can result in fast plaque progression, increased necrotic cores, and decreased stability. Our research shows that the use of AAV8 through gene editing allows the liver to express LOX-1 receptors that are more sensitive to Ox-LDL, so that it can continue to bind Ox-LDL in the circulation and exploit the liver's strong lipid metabolism ability to physiologically clear Ox-LDL, which can inhibit the rapid progress of advanced plaque and increase the stability of plaque.

Distinguishing feature of gut microbiota in Tibetan highland coronary artery disease patients and its link with diet.

The prevalence of coronary artery disease (CAD) in Tibetan Highlanders is lower than that in plain-living individuals, but the mechanism still unclear. Gut microbiota (GM) disorder is considered one of the potential factors involved in the pathogenesis of CAD, but the GM characteristics of Tibetan Highlanders suffering from CAD are unknown. We sequenced the V3-V4 region of the 16S ribosomal RNA of gut bacteria from fecal samples from Tibetan and Han CAD patients and healthy individuals inhabiting the Qinghai-Tibet Plateau, as well as from Han CAD patients and healthy individuals living at sea level, and we analyzed the GM characteristics of these subjects by bioinformatics analysis. The results showed that Tibetan Highlanders suffering from CAD had higher GM α-diversity, with differently distributed cluster compared with healthy Tibetan Highlanders and Han CAD patients living at high and low altitudes. Genera Catenibacterium, Clostridium_sensu_stricto, Holdemanella, and Ruminococcus 2 were enriched in Tibetan Highlanders suffering from CAD compared with healthy Tibetan Highlanders and Han CAD patients living at high- and low-altitudes. Prevotella was enriched in Tibetan Highlanders suffering from CAD compared with Han CAD patients living at high- and low-altitudes. Moreover, Catenibacterium was positively correlated with Prevotella. Additionally, Catenibacterium, Holdemanella, and Prevotella were positively correlated with fermented dairy product, carbohydrate and fiber intake by the subjects, while Clostridium_sensu_stricto was negatively correlated with protein intake by the subjects. In conclusion, our study indicated that Tibetan Highlanders suffering from CAD showed distinct GM, which was linked to their unique dietary characteristics and might associated with CAD.

Case Report: Glucocorticoid Effect Observation in a Ureteral Urothelial Cancer Patient With ICI-Associated Myocarditis and Multiple Organ Injuries.

Immune checkpoint inhibitor (ICI)-associated immune-related adverse events (irAEs) are becoming important safety issues worthy of attention despite the exciting therapeutic prospects. The growing development of new ICIs also brings new cases of irAEs, raising more challenges to clinicians. Cardiac injury is rare but life-threatening among diverse organ injuries, and effective interventions are critical for patients. Here, we report a novel programmed cell death protein-1 (PD-1) inhibitor tislelizumab-associated severe myocarditis and myositis accompanied by liver and kidney damage in a ureteral urothelial cancer patient, who was firstly treated by cardiologists because of cardiac symptoms. Due to the lack of experience about ICI-associated irAEs, an initial low-dose (0.5 mg/kg/day) and short-term methylprednisolone therapy was used and found to be ineffective and risky to the patient; then, steroid therapy was modulated to a higher dose (1.5 mg/kg/day) with prolonged time course, and improvement of patient symptoms and laboratory markers were observed quickly and persistently. The patient did not show adverse events under this steroid dosage. This case reports a rare tislelizumab-related myocarditis and multiple organ injuries, which provides valuable experience to cardiologists like us. Early recognition of ICI-associated myocarditis and sufficient dosage and time course of glucocorticoid therapy are critical for severe cases. High-quality clinical evidence about the precise diagnosis and therapy in ICI-associated myocarditis and other organ injuries are necessary to guide our clinical works.

Distinct Features of Gut Microbiota in High-Altitude Tibetan and Middle-Altitude Han Hypertensive Patients.

Indigenous animals show unique gut microbiota (GM) in the Tibetan plateau. However, it is unknown whether the hypertensive indigenous people in plateau also have the distinct gut bacteria, different from those living in plains. We sequenced the V3-V4 region of the gut bacteria 16S ribosomal RNA (rRNA) gene of feces samples among hypertensive patients (HPs) and healthy individuals (HIs) from 3 distinct altitudes: Tibetans from high altitude (3600-4500 m, n = 38 and 34), Hans from middle altitude (2260 m, n = 49 and 35), and Hans from low altitude (13 m, n = 34 and 35) and then analyzed the GM composition among hypertensive and healthy subgroups using the bioinformatics analysis, respectively. The GM of high-altitude Tibetan and middle-altitude Han HPs presented greater α- and ß-diversities, lower ratio of Firmicutes/Bacteroidetes (F/B), and higher abundance of beneficial Verrucomicrobia and Akkermansia than the low-altitudes HPs did. The GM of high-altitude Tibetan and middle-altitude HIs showed greater α-diversity and lower ratio of F/B than the low-altitudes HIs did. But, ß-diversity and abundance of Verrucomicrobia and Akkermansia among different subgroups of HIs did not show any differences. Conclusively, the high-altitude Tibetan and middle-altitude Han HPs have a distinct feature of GM, which may be important in their adaptation to hypertension in the plateau environments.

Vaccine Targeted Alpha 1D-Adrenergic Receptor for Hypertension.

The α1-AR (α1 adrenergic receptor) blockers currently on the market cannot meet clinical needs because of low-selectivity for subtypes of α1-ARs, short half-life, and uncertain role in cardiovascular end point events. The study sought to find a vaccine specifically against α1D-AR (α1D-adrenergic receptor) for treating hypertension. A short peptide ADR-004 (cgiteeagy) belonging to α1D-AR was screened, and the ADRQß-004 vaccine was produced and injected into spontaneously hypertensive rats model (including a short-term study, 10 weeks, and a long-term observation study, 39 weeks) and NG-nitro-l-arginine methyl ester + spontaneously hypertensive rats model (15 weeks). The antihypertensive effect and target organ protection of the ADRQß-004 vaccine were carefully evaluated. The possible immune-mediated damage was detected in normal vaccinated Sprague Dawley rats. The ADR-004 peptide has perfect immunogenicity, and the ADRQß-004 vaccine could induce strong antibody production. In the short-term study, the ADRQß-004 vaccine averagely decreased the systolic blood pressure of spontaneously hypertensive rats up to 15 mm Hg and that of NG-nitro-l-arginine methyl ester+spontaneously hypertensive rats up to 29 mm Hg. In the long-term observation model, the antihypertensive effect of the ADRQß-004 vaccine was quite stable, and the average decline of systolic blood pressure was 22 mm Hg. The ADRQß-004 vaccine effectively prevented vascular structural remodeling, cardiac hypertrophy and fibrosis, and renal injury of hypertensive animals, superior to prazosin at renal level. Moreover, the ADRQß-004 vaccine obviously downregulated the expression of α1D-AR, but not α1A-AR. Additionally, no significant immune-mediated damage was detected in immunized animals. The present results demonstrate that the ADRQß-004 vaccine may provide a novel and promising method for the treatment of hypertension.

Apolipoprotein B-100 peptide 210 antibody inhibits atherosclerosis by regulation of macrophages that phagocytize oxidized lipid.

Immunization with peptides derived from apolipoprotein B-100 (ApoB-100) has been shown to ameliorate atherosclerosis in apolipoprotein E knockout (ApoE-/-) mice. However, the exact mechanism underlying the therapeutic effects remains elusive. To shed light on this mechanism, we immunized ApoE-/- mice that were fed a Western diet with either malondialdehyde-modified ApoB-100 peptide 210 (P210) emulsified in Freund's adjuvant or anti-malondialdehyde-modified P210 antibody (P210-Ab). Mice immunized with Freund's adjuvant or bovine serum albumin served as controls. Macrophages were incubated in vitro with oxidized low-density lipoprotein (ox-LDL) or ox-LDL plus P210-Ab. Our results show that P210-Ab promoted cholesterol efflux, inhibited lipid accumulation in vitro, and reduced plasma levels of high-sensitivity C-reactive protein (hsCRP), monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6). Furthermore, dramatically increased the expression of Fc receptors (FcR) on peripheral blood mononuclear macrophages, suggesting that the mechanism of phagocytosis of ox-LDL by mononuclear macrophages may rely more on FcR than the cluster of differentiation 36 (CD36) scavenger receptor with P210-Ab. Both in vitro and in vivo, P210-Ab triggered the promoter of ATP-binding cassette transporter A1 (ABCA1) to increase peroxisome proliferator-activated receptor alpha (α) activity and inhibit the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway. In addition, P210-Ab significantly attenuated macrophage infiltration and markedly improved the stability of atheromatous plaque. In conclusion, the anti-atherosclerotic effect of P210-Ab is related to its preferential inhibition of inflammation and reversion of cholesterol transportation by altering the pathway by which macrophages phagocytize ox-LDL.

A Stepped Frequency Sweeping Method for Nonlinearity Measurement of Microresonators.

In order to measure the nonlinear features of micromechanical resonators, a free damped oscillation method based on stair-stepped frequency sinusoidal pulse excitation is investigated. In the vicinity of the resonant frequency, a frequency stepping sinusoidal pulse sequence is employed as the excitation signal. A set of free vibration response signals, containing different degrees of nonlinear dynamical characteristics, are obtained. The amplitude-frequency curves of the resonator are acquired from the forced vibration signals. Together with a singular spectrum analysis algorithm, the instantaneous amplitudes and instantaneous frequencies are extracted by a Hilbert transform from the free vibration signals. The calculated Backbone curves, and frequency response function (FRF) curves are distinct and can be used to characterize the nonlinear dynamics of the resonator. Taking a Duffing system as an example, numerical simulations are carried out for free vibration response signals in cases of different signal-to-noise ratios (SNRs). The results show that this method displays better anti-noise performance than FREEVIB. A vibrating ring microgyroscope is experimentally tested. The obtained Backbone and FRF curves agree with those obtained by the traditional frequency sweeping method. As a test technique, the proposed method can also be used to for experimentally testing the dynamic characteristics of other types of micromechanical resonators.