Regulation of angiogenic behaviors by oxytocin receptor through Gli1-indcued transcription of HIF-1α in human umbilical vein endothelial cells

Wenyang Huazhuo Tongluo formula alleviates pulmonary vascular injury and downregulates HIF-1α in bleomycin-induced systemic sclerosis mouse model

Background

Vascular damage, autoimmune abnormalities, and fibrosis are the three pathological features of systemic sclerosis (SSc).However, pulmonary vascular damage is the main factor affecting the progression and prognosis of SSc. The main purpose of this study was to explore the molecular mechanism of Wenyang Huazhuo Tongluo Formula in alleviating pulmonary vascular injury in bleomycin-induced SSc mouse model.

Methods

Masson staining and H&E staining were used to analyze the degree of pulmonary vascular fibrosis and the infiltration of leukocyte cells in lung tissue ofbleomycin-induced SSc mouse models treated with saline (BLM group), Wenyang Huazhuo Tongluo Formula (WYHZTL group) and HIF-1α inhibitor KC7F2 (KC7F2 group). Blood vessel exudation was determined by analyzing the cell number and albumin concentration in bronchoalveolar lavage fluid using a cell counter and ELISA assay, respectively. The degree of vascular injury was assessed by measuring the expression levels of vWF, E-selectin, ICAM-1, VCAM-1, VE-cadherin and claudin-5 in serum and pulmonary vascular endothelial cells using ELISA and immunofluorescence staining. Finally, the effect of Wenyang Huazhuo Tongluo Formula on the expression of HIF-1α was detected using immunofluorescence staining.

Results

Wenyang Huazhuo Tongluo Formula and KC7F2 significantly inhibited bleomycin-induced pulmonary vascular fibrosis and the level of perivascular inflammatory cell infiltration. The number of cells and the concentration of albumin were significantly reduced in the bronchoalveolar lavage fluid of the WYHZTL group and KC7F2 group compared with the BLM group. In addition, treatment with Wenyang Huazhuo Tongluo Formula and KC7F2 significantly downregulated the expression levels of vWF, E-selectin, ICAM-1, VCAM-1 and HIF-1α, but upregulated the expression of VE-cadherin and claudin-5 in serum and pulmonary vascular endothelial cells, compared with treatment with saline.

Conclusions

This study reveals that Wenyang Huazhuo Tongluo Formula plays a new role in the treatment of SSc by alleviating pulmonary vascular damage. Furthermore, we found that Wenyang Huazhuo Tongluo Formula alleviates pulmonary vascular injury and inhibits HIF-1α expression.

The Importance of Experimental Investigation of the Peripheral Oxytocin System

Oxytocin and oxytocin receptors are synthesized in the periphery where paracrine/autocrine actions have been described alongside endocrine actions effected by central release of oxytocin from the posterior pituitary. In the female reproductive system, classical actions of uterine contraction and milk ejection from mammary glands are accompanied by actions in the ovaries where roles in steroidogenesis, follicle recruitment and ovulation have been described. Steroidogenesis, contractile activity, and gamete health are similarly affected by oxytocin in the male reproductive tract. In the cardiovascular system, a local oxytocinergic system appears to play an important cardio-protective role. This role is likely associated with emerging evidence that peripheral oxytocin is an important hormone in the endocrinology of glucose homeostasis due to its actions in adipose, the pancreas, and the largely ignored oxytocinergic systems of the adrenal glands and liver. Gene polymorphisms are shown to be associated with a number of reported traits, not least factors associated with metabolic syndrome.

Advances in glioma-associated oncogene (GLI) inhibitors for cancer therapy

The Hedgehog/Glioma-associated oncogene homolog (HH/GLI) signaling pathway regulates self-renewal of rare and highly malignant cancer stem cells, which have been shown to account for the initiation and maintenance of tumor growth as well as for drug resistance, metastatic spread and relapse. As an important component of the Hh signaling pathway, glioma-associated oncogene (GLI) acts as a key signal transmission hub for various signaling pathways in many tumors. Here, we review direct and indirect inhibitors of GLI; summarize the abundant active structurally diverse natural GLI inhibitors; and discuss how to better develop and utilize GLI inhibitors to solve the problem of drug resistance in tumors of interest. In summary, GLI inhibitors will be promising candidates for various cancer treatments.

CRISPR editing of the GLI1 first intron abrogates GLI1 expression and differentially alters lineage commitment

GLI1 is one of three GLI family transcription factors that mediate Sonic Hedgehog signaling, which plays a role in development and cell differentiation. GLI1 forms a positive feedback loop with GLI2 and likely with itself. To determine the impact of GLI1 and its intronic regulatory locus on this transcriptional loop and human stem cell differentiation, we deleted the region containing six GLI binding sites in the human GLI1 intron using CRISPR/Cas9 editing to produce H1 human embryonic stem cell (hESC) GLI1‐edited clones. Editing out this intronic region, without removing the entire GLI1 gene, allowed us to study the effects of this highly complex region, which binds transcription factors in a variety of cells. The roles of GLI1 in human ESC differentiation were investigated by comparing RNA sequencing, quantitative‐real time PCR (q‐rtPCR), and functional assays. Editing this region resulted in GLI1 transcriptional knockdown, delayed neural commitment, and inhibition of endodermal and mesodermal differentiation during spontaneous and directed differentiation experiments. We found a delay in the onset of early osteogenic markers, a reduction in the hematopoietic potential to form granulocyte units, and a decrease in cancer‐related gene expression. Furthermore, inhibition of GLI1 via antagonist GANT‐61 had similar in vitro effects. These results indicate that the GLI1 intronic region is critical for the feedback loop and that GLI1 has lineage‐specific effects on hESC differentiation. Our work is the first study to document the extent of GLI1 abrogation on early stages of human development and to show that GLI1 transcription can be altered in a therapeutically useful way.

Cardiovascular protective properties of oxytocin against COVID-19

SARS-CoV-2 infection or COVID-19 has become a worldwide pandemic; however, effective treatment for COVID-19 remains to be established. Along with acute respiratory distress syndrome (ARDS), new and old cardiovascular injuries are important causes of significant morbidity and mortality in COVID-19. Exploring new approaches managing cardiovascular complications is essential in controlling the disease progression and preventing long-term complications. Oxytocin (OXT), an immune-regulating neuropeptide, has recently emerged as a strong candidate for treatment and prevention of COVID-19 pandemic. OXT carries special functions in immunologic defense, homeostasis and surveillance. It suppresses neutrophil infiltration and inflammatory cytokine release, activates T-lymphocytes, and antagonizes negative effects of angiotensin II and other key pathological events of COVID-19. Additionally, OXT can promote γ-interferon expression to inhibit cathepsin L and increases superoxide dismutase expression to reduce heparin and heparan sulphate fragmentation. Through these mechanisms, OXT can block viral invasion, suppress cytokine storm, reverse lymphocytopenia, and prevent progression to ARDS and multiple organ failures. Importantly, besides prevention of metabolic disorders associated with atherosclerosis and diabetes mellitus, OXT can protect the heart and vasculature through suppressing hypertension and brain-heart syndrome, and promoting regeneration of injured cardiomyocytes. Unlike other therapeutic agents, exogenous OXT can be used safely without the side-effects seen in remdesivir and corticosteroid. Importantly, OXT can be mobilized endogenously to prevent pathogenesis of COVID-19. This article summarizes our current understandings of cardiovascular pathogenesis caused by COVID-19, explores the protective potentials of OXT against COVID-19-associated cardiovascular diseases, and discusses challenges in applying OXT in treatment and prevention of COVID-19.

Chemical compounds

Angiotensin-converting enzyme 2 (ACE2); atrial natriuretic peptide (ANP); cathepsin L; heparan sulphate proteoglycans (HSPGs); interferon; interleukin; oxytocin; superoxide dismutase; transmembrane serine protease isoform 2 (TMPRSS2).

Cleaved Caspase-3 Transcriptionally Regulates Angiogenesis-Promoting Chemotherapy Resistance

Caspases are well known for their role in apoptosis. Recently, nonapoptotic roles of caspases have been identified, however, these noncanonical roles are not well documented and the mechanisms involved are not fully understood. Here, we studied the role of cleaved caspase-3 using human- and mouse-proficient caspase-3 cancer cell lines and human-deficient caspase-3 cancer cells. Cleaved caspase-3 functioned as a transcription factor and directly bound to DNA. A DNA-binding domain was identified in the small subunit of caspase-3 and an active conformation was essential for caspase-3 transcriptional activity. Caspase-3 DNA binding enhanced angiogenesis by upregulating the expression of proangiogenic genes and by activating pathways that promoted endothelial cell activation. Some proapoptotic genes were downregulated in caspase-3-proficient cells. Inhibiting caspase-3 increased the efficacy of chemotherapy and decreased spontaneous tumor development. These data highlight a novel nonapoptotic role of caspase-3 and suggest that cleaved caspase-3 could be a new therapeutic target in cancer. SIGNIFICANCE: These findings report a noncanonical function of caspase-3 by demonstrating its ability to transcriptionally regulate the VEGFR pathway.

Therapeutic Potential of Oxytocin in Atherosclerotic Cardiovascular Disease: Mechanisms and Signaling Pathways

Coronary artery disease (CAD) is a major cardiovascular disease responsible for high morbidity and mortality worldwide. The major pathophysiological basis of CAD is atherosclerosis in association with varieties of immunometabolic disorders that can suppress oxytocin (OT) receptor (OTR) signaling in the cardiovascular system (CVS). By contrast, OT not only maintains cardiovascular integrity but also has the potential to suppress and even reverse atherosclerotic alterations and CAD. These protective effects of OT are associated with its protection of the heart and blood vessels from immunometabolic injuries and the resultant inflammation and apoptosis through both peripheral and central approaches. As a result, OT can decelerate the progression of atherosclerosis and facilitate the recovery of CVS from these injuries. At the cellular level, the protective effect of OT on CVS involves a broad array of OTR signaling events. These signals mainly belong to the reperfusion injury salvage kinase pathway that is composed of phosphatidylinositol 3-kinase-Akt-endothelial nitric oxide synthase cascades and extracellular signal-regulated protein kinase 1/2. Additionally, AMP-activated protein kinase, Ca²⁺/calmodulin-dependent protein kinase signaling and many others are also implicated in OTR signaling in the CVS protection. These signaling events interact coordinately at many levels to suppress the production of inflammatory cytokines and the activation of apoptotic pathways. A particular target of these signaling events is endoplasmic reticulum (ER) stress and mitochondrial oxidative stress that interact through mitochondria-associated ER membrane. In contrast to these protective effects and machineries, rare but serious cardiovascular disturbances were also reported in labor induction and animal studies including hypotension, reflexive tachycardia, coronary spasm or thrombosis and allergy. Here, we review our current understanding of the protective effect of OT against varieties of atherosclerotic etiologies as well as the approaches and underlying mechanisms of these effects. Moreover, potential cardiovascular disturbances following OT application are also discussed to avoid unwanted effects in clinical trials of OT usages.

Oxytocin effects on experimental skin wound healing

OBJECTIVE

Oxytocin (OXY) has significant effects on mammalian behavior. Next to its role in lactation and social interactions, it is described to support better wound healing as well. However, direct OXY effects on wound healing and the regeneration of the microvascular network are still not clarified. We therefore examined the effects of OXY and an OXY receptor antagonist [atosiban (ATO)] on skin wound healing, focusing on epithelialization and neovascularization.

METHODS

Skin wound healing has been assessed using intravital fluorescence microscopy in a model of full dermal thickness wounds in the dorsal skin fold chamber of hairless mice. Animals received repetitive low or high doses of OXY or ATO. Morphological and cellular characterization of skin tissue repair was performed by histology and in vitro cell assays.

RESULTS

The assessment of skin tissue repair using this therapy regimen showed that OXY and ATO had no major influence on epithelialization, neovascularization, wound cellularity, or inflammation. Moreover, OXY and ATO did neither stimulate nor deteriorate keratinocyte or fibroblast migration and proliferation.

CONCLUSION

In summary, this study is the first to demonstrate that OXY application does not impair skin wound healing or cell behavior. However, until now, the used transmitter system seems not to be clarified in detail, and it might be proposed that it is associated with the stress response of the organism to various stimuli.