Adenovirus-mediated Overexpression of FcγRIIB Attenuates Pulmonary Inflammation and Fibrosis.

Progressive fibrosing interstitial lung diseases (PF-ILDs) result in high mortality and lack effective therapies. The pathogenesis of PF-ILDs involves macrophages driving inflammation and irreversible fibrosis. Fc-γ receptors (FcγRs) regulate macrophages and inflammation, but their roles in PF-ILDs remain unclear. We characterized the expression of FcγRs and found upregulated FcγRIIB in human and mouse lungs after exposure to silica. FcγRIIB deficiency aggravated lung dysfunction, inflammation, and fibrosis in silica-exposed mice. Using single-cell transcriptomics and in vitro experiments, FcγRIIB was found in alveolar macrophages, where it regulated the expression of fibrosis-related genes Spp1 and Ctss. In mice with macrophage-specific overexpression of FcγRIIB and in mice treated with adenovirus by intratracheal instillation to upregulate FcγRIIB, silica-induced functional and histological changes were ameliorated. Our data from three genetic models and a therapeutic model suggest that FcγRIIB plays a protective role that can be enhanced by adenoviral overexpression, representing a potential therapeutic strategy for PF-ILDs.

Blocking FcγRIIB in Smooth Muscle Cells Reduces Hypertension.

[Figure: see text].

Mep1a contributes to Ang II-induced cardiac remodeling by promoting cardiac hypertrophy, fibrosis and inflammation.

Pathological cardiac remodeling, characterized by excessive deposition of extracellular matrix proteins and cardiac hypertrophy, leads to the development of heart failure. Meprin α (Mep1a), a zinc metalloprotease, previously reported to participate in the regulation of inflammatory response and fibrosis, may also contribute to cardiac remodeling, although whether and how it participates in this process remains unknown. Here, in this work, we investigated the role of Mep1a in pathological cardiac remodeling, as well as the effects of the Mep1a inhibitor actinonin on cardiac remodeling-associated phenotypes. We found that Mep1a deficiency or chemical inhibition both significantly alleviated TAC- and Ang II-induced cardiac remodeling and dysfunction. Mep1a deletion and blocking both attenuated TAC- and Ang II-induced heart enlargement and increases in the thickness of the left ventricle anterior and posterior walls, and reduced expression of pro-hypertrophic markers, including atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and myosin heavy chain beta (ß-MHC). In addition, Mep1a deletion and blocking significantly inhibited TAC- and Ang II-induced cardiac fibroblast activation and production of extracellular matrix (ECM). Moreover, in Mep1a-/- mice and treatment with actinonin significantly reduced Ang II-induced infiltration of macrophages and proinflammatory cytokines. Notably, we found that in vitro, Mep1a is expressed in cardiac myocytes and fibroblasts and that Mep1a deletion or chemical inhibition both markedly suppressed Ang II-induced hypertrophy of rat or mouse cardiac myocytes and activation of rat or mouse cardiac fibroblasts. In addition, blocking Mep1a in macrophages reduced Ang II-induced expression of interleukin (IL)-6 and IL-1ß, strongly suggesting that Mep1a participates in cardiac remodeling processes through regulation of inflammatory cytokine expression. Mechanism studies revealed that Mep1a mediated ERK1/2 activation in cardiac myocytes, fibroblasts and macrophages and contributed to cardiac remodeling. In light of our findings that blocking Mep1a can ameliorate cardiac remodeling via inhibition of cardiac hypertrophy, fibrosis, and inflammation, Mep1a may therefore serve as a strong potential candidate for therapeutic targeting to prevent cardiac remodeling.

P14ARF inhibits regional inflammation and vascularization in intervertebral disc degeneration by upregulating TIMP3.

In this study, we identified P14 alternate reading frame (P14ARF) as a novel regulator of inflammation and vascularization in intervertebral disk degeneration (IVDD). We collected IVD tissues from IVDD patients and normal individuals for analysis of P14ARF expression. We also induced experimental IVDD by needle puncture injuries in the caudal intervertebral disks of Sprague-Dawley (SD) rats and achieved recombinant adenovirus-mediated P14ARF overexpression in experimental IVDD rats. Regulation relationships between P14ARF and tissue inhibitors of metalloproteinases-3 (TIMP3) were confirmed in P14ARF-overexpressed and TIMP3-depleted nucleus pulposus (NP) cells. Tube formation in vitro was evaluated in coculture systems of human umbilical vein endothelial cells (HUVECs) and rat degenerated NP cells (DNPCs). Inflammatory response was assessed from levels of TNF-α, IL-1ß, and IL-6 and neovascularization from expression of endothelial growth factor (VEGF). The P14ARF and TIMP3 were downregulated in degenerated IVD tissue derived from patients and experimental IVDD rats. Overexpressed P14ARF suppressed inflammatory cytokine levels and vascularization. There was decreased in vitro tube formation in response to P14ARF overexpression and TIMP3 elevation. Finally, attenuated inflammatory responses and suppression of VEGF were achieved by P14ARF-mediated promotion of TIMP3 in rat DNPCs. Taken together, the present study reveals that P14ARF/TIMP3 modulation of inflammatory response and vascularization in the context of IVDD highlights a potential target for future therapeutic strategies.

Fc Gamma Receptor IIb Expressed in Hepatocytes Promotes Lipid Accumulation and Gluconeogenesis.

Non-alcoholic fatty liver disease (NAFLD) is characterized by ectopic lipid accumulation in the liver, usually combined with hepatic insulin resistance. Fc-gamma receptor-IIb (FcγRIIb) and its ligand are reported to be associated with obesity and type 2 diabetes mellitus (T2DM). As knowledge about FcγRIIb in the literature is mostly generated from studies on skeletal muscle tissue, the expression and function of FcγRIIb in the liver and hepatocytes are largely unknown. In this study, we identified the expression of FcγRIIb in primary cultured mouse hepatocytes: FcγRIIb was upregulated in response to oleic acid (OA) in a dose dependent manner. FcγRIIb knockdown using shRNA suppressed the lipid and triglyceride accumulation, and mRNA expression of ACC1, FASn, CD36, MTTP, and ApoB in OA-treated HepG2 cells. FcγRIIb deficiency mice fed with high fat diet (HFD) had significantly lower liver weight and liver to body weight ratio, as well as less triglyceride accumulation in the livers. In glycometabolism, FcγRIIb hindered insulin-induced phosphorylation of AKT and FOXO1, and in turn upregulated G6Pase and PEPCK mRNA expression, suggesting that FcγRIIb promotes gluconeogenesis by suppressing the AKT/FOXO1/G6Pase/PEPCK pathway in hepatocytes. This study reveals a novel role for FcγRIIb in regulating lipid metabolism and glycometabolism, and provides a new therapeutic target to improve NAFLD.

Ozonated autohemotherapy combined with pulsed radiofrequency in the treatment of thoracic postherpetic neuralgia in older adults: a retrospective study.

Postherpetic neuralgia (PHN) seriously affects the quality of life of the elderly population. This study aimed to evaluate the efficacy of ozonated autohemotherapy (O3-AHT) combined with pulsed radiofrequency (PRF) in the treatment of thoracic PHN in older adults. The medical records of patients with thoracic PHN aged 65 years and older from June 2018 until March 2021 in Shengli Oilfield Central Hospital were reviewed. They were assigned into two groups: PRF alone (PRF group, n = 107) and PRF combined with O3-AHT (PRF + O3-AHT group, n = 109). Visual Analogue Scale for pain was evaluated at pre-treatment, 1 day, 1, 3 and 6 months after treatment. Quality of life and sleep quality were assessed using Short-Form 36 Health Survey and Athens Insomnia Scale at pre-treatment and 6 months post-treatment, respectively. The median age of patients in the PRF and PRF + O3-AHT groups were 69 (67-73) years and 68 (67-72) years, respectively. The former included 62 females and the latter included 51 females. Compared with pre-treatment, the Visual Analogue Scale scores of two groups declined at post-treatment. Patients in the PRF + O3-AHT group showed obviously lower Visual Analogue Scale scores compared with those in the PRF group at 1, 3, and 6 months after treatment and they had earlier withdrawal time for drugs. However, dizziness, tachycardia, sleepiness, and nausea were presented after combination therapy. These symptoms resolved spontaneously after a period of rest. Additionally, O3-AHT combined with PRF was associated with a significant decrease in the Athens Insomnia Scale score and with a significant improvement in every dimension of the Short-Form 36 Health Survey. To conclude, O3-AHT combined with PRF is an effective way to relieve thoracic PHN in older patients.

The role of immunoglobulin E and mast cells in hypertension.

AIMS: Hypertension is the major cause of cardiovascular diseases and global mortality. Immunoglobulin E (IgE), which plays crucial roles in allergic diseases, has been implicated in the pathogenesis of vascular and cardiac remodelling via its receptor (FcεR1). In this study, we aimed to reveal the role of IgE and FcεR1 in hypertension. METHODS AND RESULTS: Herein, we reported that IgE levels were significantly increased in hypertensive patients as well as in hypertensive mice induced by angiotensin II (Ang II). Ang II-induced vascular remodelling and hypertension were significantly alleviated in FcεR1 genetic knockout mice or in mice treated with anti-IgE monoclonal antibody. Similarly, treatment with omalizumab (a clinical IgE antagonist) also markedly inhibited Ang II-induced hypertension. Furthermore, the cellular contribution of IgE-FcεR1 in hypertension was evaluated in mice with FcεR1 conditional knockout in mast cell (MC), smooth muscle cell (SMC), or endothelial cell (EC). Our data revealed that IgE-mediated hypertension is largely dependent on FcεR1 in MCs but not SMCs and ECs. Finally, RNA-seq and signalling pathway analyses of mouse bone marrow-derived MCs suggested that interleukin 6 (IL-6) is one of critical mediators in IgE-mediated hypertension. IL-6 derived from IgE-stimulated MCs promoted reactive oxygen species production and decreased the levels of phosphorylated endothelial nitric oxide synthase in ECs, leading to endothelial dysfunction. CONCLUSION: Our findings reveal that IgE contributes to the pathogenesis of hypertension, at least partially through activating the IgE-FcεR1 signalling in MCs. Thus, IgE may represent a new therapeutic target for IgE-mediated hypertension.

Phosphodiesterase 4D promotes angiotensin II-induced hypertension in mice via smooth muscle cell contraction.

Hypertension is a common chronic disease, which leads to cardio-cerebrovascular diseases, and its prevalence is increasing. The cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) pathway participates in multiple cardiovascular diseases. Phosphodiesterase (PDE) 4 has been shown to regulate PKA activity via cAMP specific hydrolysis. However, whether PDE4-cAMP-PKA pathway influences hypertension remains unknown. Herein, we reveal that PDE4D (one of PDE4 isoforms) expression is upregulated in the aortas of experimental hypertension induced by angiotensin II (Ang II). Furthermore, knockout of Pde4d in mouse smooth muscle cells (SMCs) attenuates Ang II-induced hypertension, arterial wall media thickening, vascular fibrosis and vasocontraction. Additionally, we find that PDE4D deficiency activates PKA-AMP-activated protein kinase (AMPK) signaling pathway to inhibit myosin phosphatase targeting subunit 1 (MYPT1)-myosin light chain (MLC) phosphorylation, relieving Ang II-induced SMC contraction in vitro and in vivo. Our results also indicate that rolipram, a PDE4 inhibitor, may be a potential drug for hypertension therapy.

Phosphodiesterase 4D contributes to angiotensin II-induced abdominal aortic aneurysm through smooth muscle cell apoptosis.

Abdominal aortic aneurysm (AAA) is a permanent expansion of the abdominal aorta that has a high mortality but limited treatment options. Phosphodiesterase (PDE) 4 family members are cAMP-specific hydrolyzing enzymes and have four isoforms (PDE4A-PDE4D). Several pan-PDE4 inhibitors are used clinically. However, the regulation and function of PDE4 in AAA remain largely unknown. Herein, we showed that PDE4D expression is upregulated in human and angiotensin II-induced mouse AAA tissues using RT-PCR, western blotting, and immunohistochemical staining. Furthermore, smooth muscle cell (SMC)-specific Pde4d knockout mice showed significantly reduced vascular destabilization and AAA development in an experimental AAA model. The PDE4 inhibitor rolipram also suppressed vascular pathogenesis and AAA formation in mice. In addition, PDE4D deficiency inhibited caspase 3 cleavage and SMC apoptosis in vivo and in vitro, as shown by bulk RNA-seq, western blotting, flow cytometry and TUNEL staining. Mechanistic studies revealed that PDE4D promotes apoptosis by suppressing the activation of cAMP-activated protein kinase A (PKA) instead of the exchange protein directly activated by cAMP (Epac). Additionally, the phosphorylation of BCL2-antagonist of cell death (Bad) was reversed by PDE4D siRNA in vitro, which indicates that PDE4D regulates SMC apoptosis via the cAMP-PKA-pBad axis. Overall, these findings indicate that PDE4D upregulation in SMCs plays a causative role in AAA development and suggest that pharmacological inhibition of PDE4 may represent a potential therapeutic strategy.

Advanced Research of Abdominal Aortic Aneurysms on Metabolism.

Abdominal aortic aneurysm (AAA) is a cardiovascular disease with a high risk of death, seriously threatening the life and health of people. The specific pathogenesis of AAA is still not fully understood. In recent years, researchers have found that amino acid, lipid, and carbohydrate metabolism disorders play important roles in the occurrence and development of AAA. This review is aimed to summarize the latest research progress of the relationship between AAA progression and body metabolism. The body metabolism is closely related to the occurrence and development of AAA. It is necessary to further investigate the pathogenesis of AAA from the perspective of metabolism to provide theoretical basis for AAA diagnosis and drug development.

Single-Cell Transcriptome Profiles Reveal Fibrocytes as Potential Targets of Cell Therapies for Abdominal Aortic Aneurysm.

Abdominal aortic aneurysm (AAA) is potentially life-threatening in aging population due to the risk of aortic rupture and a lack of optimal treatment. The roles of different vascular and immune cells in AAA formation and pathogenesis remain to be future characterized. Single-cell RNA sequencing was performed on an angiotensin (Ang) II-induced mouse model of AAA. Macrophages, B cells, T cells, fibroblasts, smooth muscle cells and endothelial cells were identified through bioinformatic analyses. The discovery of multiple subtypes of macrophages, such as the re-polarization of Trem2 + Acp5 + osteoclast-like and M2-like macrophages toward the M1 type macrophages, indicates the heterogenous nature of macrophages during AAA development. More interestingly, we defined CD45+COL1+ fibrocytes, which was further validated by flow cytometry and immunostaining in mouse and human AAA tissues. We then reconstituted these fibrocytes into mice with Ang II-induced AAA and found the recruitment of these fibrocytes in mouse AAA. More importantly, the fibrocyte treatment exhibited a protective effect against AAA development, perhaps through modulating extracellular matrix production and thus enhancing aortic stability. Our study reveals the heterogeneity of macrophages and the involvement of a novel cell type, fibrocyte, in AAA. Fibrocyte may represent a potential cell therapy target for AAA.

Overexpression of TIMP3 inhibits discogenic pain by suppressing angiogenesis and the expression of substance P in nucleus pulposus.

Approximately 50% of the cases of low back pain (LBP) are attributed to discogenic origin. The causes of discogenic pain are complicated and consist of a complex biochemical cascade. Neovascularization of intervertebral discs (IVDs) is believed to be associated with discogenic pain. The anti­angiogenesis ability of tissue inhibitor of metalloproteinase­3 (TIMP3) has been reported in many tumors, yet whether TIMP3 is associated with neovascularization of IVDs remains unknown. In the present study, both in vitro and in vivo models were used to investigate the association between discogenic pain and TIMP3 expression in nucleus pulposus (NP). PCR results demonstrated that inflammation induced downregulation of TIMP3 expression in NP cells. By using an adenovirus system to upregulate TIMP3 expression, the effect of TIMP3 on angiogenesis was measured by endothelial cell migration and tube formation assays. The results demonstrated that overexpression of TIMP3 suppressed angiogenesis in NP without the regulation of vascular endothelial growth factor (VEGF) expression. TNF­α converting enzyme (TACE) expression was downregulated by TIMP3, thus inhibiting the TACE­induced activation of TNF­α in NP cells. Immunohistochemical staining of IVDs also confirmed that TIMP3 inhibited the expression of substance P in NP. Taken together, the present results indicated the expression of TIMP3 in NP may have a key role in the development of discogenic pain.

Meprin-α (Mep1A) enhances TNF-α secretion by mast cells and aggravates abdominal aortic aneurysms.

BACKGROUND AND PURPOSE: Abdominal aorticaneurysm (AAA) rupture is mainly due to elastic lamina degradation. As a metalloendopeptidase, meprin-α (Mep1A) critically modulates the activity of proteins and inflammatory cytokines in various diseases. Here, we sought to investigate the functional role of Mep1A in AAA formation and rupture. EXPERIMENTAL APPROACH: AAA tissues were detected by using real-time PCR (RT-PCR), western blotting (WB), and immunohistochemistry. Further mechanistic studies used RT-PCR, WB, and enzyme-linked immunosorbent assays. KEY RESULTS: Mep1A mediated AAA formation by regulating the mast cell (MC) secretion of TNF-α, which promoted matrix metalloproteinase (MMP) expression and apoptosis in smooth muscle cells (SMCs). Importantly, increased Mep1A expression was found in human AAA tissues and in angiotensin II-induced mouse AAA tissues. Mep1A deficiency reduced AAA formation and increased the survival rate of AAA mice. Pathological analysis showed that Mep1A deletion decreased elastic lamina degradation and SMC apoptosis in AAA tissues. Furthermore, Mep1A was expressed mainly in MCs, wherein it mediated TNF-α expression. Mep1A inhibitor actinonin significantly inhibited TNF-α secretion in MCs. TNF-α secreted by MCs enhanced MMP2 expression in SMCs and promoted SMC apoptosis. CONCLUSION AND IMPLICATIONS: Taken together, these data suggest that Mep1A may be vital in AAA pathophysiology by regulating TNF-α production by MCs. Knocking out Mep1A significantly decreased AAA diameter and improved AAA stability in mice. Therefore, Mep1A is a potential new therapeutic target in the development of AAA.

MicroRNA-448 modulates the progression of neuropathic pain by targeting sirtuin 1.

MicroRNAs (miRNAs) play crucial roles in the pathogenesis of neuropathic pain. The present study investigated the effects of miR-448 on the progression of neuropathic pain in a rat model of chronic constriction injury (CCI) of the sciatic nerve. Reverse-transcription quantitative polymerase chain reaction was conducted to detect the gene expression. The paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) were used to assess the pain threshold. The protein expression levels of interleukin (IL)-6, IL-1ß and tumor necrosis factor-α (TNF-α) were detected by ELISA. The target of miR-448 was predicted by TargetScan software. The Student's t-test or one-way ANOVA were used to identify statistical differences among groups. miR-448 was persistently upregulated in CCI rats, and both mechanical allodynia and thermal hyperalgesia in CCI rats were decreased following miR-448 downregulation. The expression levels of IL-1ß, IL-6 and TNF-α were significantly increased in CCI rats compared with controls, and these effects were reversed following treatment with a miR-448 inhibitor. A luciferase reporter assay revealed that sirtuin 1 (SIRT1) was a target gene of miR-448. SIRT1 was found to abrogate the effect of miR-448 on neuropathic pain development. Collectively, the results of the present study revealed that miR-448 promoted neuropathic pain in CCI rats by regulating neuroinflammation via SIRT1. Therefore, SIRT1 may be considered as a novel biomarker for neuropathic pain.

IMM-H007 improves heart function via reducing cardiac fibrosis.

Cardiac dysfunction is a pathological state characterized by damaged ability of the left ventricle (LV) to either eject or fill blood accompanied by cardiac hypertrophy and fibrosis. IMM-H007, an adenosine derivative, is an activator of AMP-Activated Protein Kinase (AMPK). AMPK can decrease the transforming growth factor-ß1 (TGF-ß1) expression during fibrosis. Therefore, we hypothesized that IMM-H007 contributed to cardiac dysfunction by mediating cardiac fibrosis. To test this hypothesis, we used angiotensin II (AngII)-induced cardiac remodeling model treated with IMM-H007 or vehicle. Echocardiography measurements showed that IMM-H007 significantly improved heart function indicated by increased LV ejection fraction (%LVEF) and LV fractional shortening (%LVFS). Histological staining and qRT-PCR analysis revealed that IMM-H007 markedly reduced AngII-induced cardiac fibroblast activation (α-smooth muscle actin and periostin) and matrix protein production (Collagen I and Collagen III). However, IMM-H007 did not affect AngII-induced cardiac hypertrophy. Immunoblotting analysis revealed that IMM-H007 activated AMPK, decreased the expression of TGF-ß1, and inhibited the activation of Smad2 in heart tissues. In mouse primary cultured cardiac fibroblasts, pharmacological activation of AMPK by IMM-H007 significantly reduced AngII-induced TGF-ß1 expression as well. Consistently, in human cardiac fibroblasts-adult ventricular (HCF-av), IMM-H007 activated AMPK and markedly suppressed AngII-induced TGF-ß1 expression. These results together reveal that IMM-H007 improves heart function, and alleviates AngII-induced cardiac fibrosis by regulating AMPK-TGF-ß1 signaling. These findings suggest IMM-H007 as a potential drug for treating cardiac dysfunction.

IgE Aggravates the Senescence of Smooth Muscle Cells in Abdominal Aortic Aneurysm by Upregulating LincRNA-p21.

Immunoglobulin E (lgE) activates immunity by binding to mast cells and basophils. It is well-known that IgE and its receptor, FcɛR1, play a key role in the development of airway inflammation and remodeling in allergic asthma. Recent studies show that IgE also plays an important role in abdominal aortic aneurysm (AAA) pathogenesis. However, the mechanism by which IgE promotes AAA remains unclear. Here we report that in our mouse model, asthma-induced high level of IgE aggravated AAA, but IgE lost this effect on AAA in FcɛR1-/- mice. Our in vitro study revealed that IgE induced smooth muscle cell senescence via upregulating lincRNA-p21 against p21 without altering expression of p53. By this mechanism, IgE accelerated AAA in ApoE-/- mice, which was blocked by knockdown of lincRNA-p21 in both vitro and vivo. This study suggests that IgE actives the lincRNAp21-p21 pathway to induce SMC senescence, which contributes to the formation of AAA, and lincRNA-p21 is a potential therapeutic target for AAA aggravated by asthma.