Bioengineered vascular grafts with a pathogenic TGFBR1 variant model aneurysm formation in vivo and reveal underlying collagen defects.

Thoracic aortic aneurysm (TAA) is a life-threatening vascular disease frequently associated with underlying genetic causes. An inadequate understanding of human TAA pathogenesis highlights the need for better disease models. Here, we established a functional human TAA model in an animal host by combining human induced pluripotent stem cells (hiPSCs), bioengineered vascular grafts (BVGs), and gene editing. We generated BVGs from isogenic control hiPSC-derived vascular smooth muscle cells (SMCs) and mutant SMCs gene-edited to carry a Loeys-Dietz syndrome (LDS)-associated pathogenic variant (TGFBR1A230T). We also generated hiPSC-derived BVGs using cells from a patient with LDS (PatientA230T/+) and using genetically corrected cells (Patient+/+). Control and experimental BVGs were then implanted into the common carotid arteries of nude rats. The TGFBR1A230T variant led to impaired mechanical properties of BVGs, resulting in lower burst pressure and suture retention strength. BVGs carrying the variant dilated over time in vivo, resembling human TAA formation. Spatial transcriptomics profiling revealed defective expression of extracellular matrix (ECM) formation genes in PatientA230T/+ BVGs compared with Patient+/+ BVGs. Histological analysis and protein assays validated quantitative and qualitative ECM defects in PatientA230T/+ BVGs and patient tissue, including decreased collagen hydroxylation. SMC organization was also impaired in PatientA230T/+ BVGs as confirmed by vascular contraction testing. Silencing of collagen-modifying enzymes with small interfering RNAs reduced collagen proline hydroxylation in SMC-derived tissue constructs. These studies demonstrated the utility of BVGs to model human TAA formation in an animal host and highlighted the role of reduced collagen modifying enzyme activity in human TAA formation.

Polymorphism of Transforming Growth Factor TGFB and Its Receptors TGFBRI, TGFBRII, TGFBRIIII Genes in Western Siberia Patients with Open-Angle Glaucoma.

Polymorphism of genes of transforming growth factor TGFB and its receptors (TGFBRI, TGFBRII, and TGFBRIIII) in patients with primary open-angle glaucoma was analyzed. The frequency of the TGFBRII CC genotype in patients is increased relative to the control group (OR=6.10, p=0.0028). Heterozygosity in this polymorphic position is reduced (OR=0.18, p=0.0052). As the effects of TGF-ß is mediated through its receptors, we analyzed complex of polymorphic variants of the studied loci in the genome of patients. Two protective complexes consisting only of receptor genes were identified: TGFBRI TT:TGFBRII CG (OR=0.10, p=0.02) and TGFBRII CG:TGFBRIII CG (OR=0.09, p=0.01). The study showed an association of TGFBRII polymorphism with primary open-angle glaucoma and the need to study functionally related genes in the development of the disease, which should contribute to its early diagnosis and prevention.

Targeted inhibition of transforming growth factor-ß type I receptor by AZ12601011 improves paraquat poisoning-induced multiple organ fibrosis.

Paraquat (PQ) causes fatal poisoning that leads to systemic multiple organ fibrosis, and transforming growth factor (TGF)-ß1 plays a critical role in this process. In this study, we aimed to investigate the effects of AZ12601011 (a small molecular inhibitor of TGFßRI) on PQ-induced multiple organ fibrosis. We established a mouse model of PQ in vivo and used PQ-treated lung epithelial cell (A549) and renal tubular epithelial cells (TECs) in vitro. Haematoxylin-eosin and Masson staining revealed that AZ12601011 ameliorated pulmonary, hepatic, and renal fibrosis, consistent with the decrease in the levels of fibrotic indicators, alpha-smooth muscle actin (α-SMA) and collagen-1, in the lungs and kidneys of PQ-treated mice. In vitro data showed that AZ12601011 suppressed the induction of α-SMA and collagen-1 in PQ-treated A549 cells and TECs. In addition, AZ12601011 inhibited the release of inflammatory factors, interleukin (IL)-1ß, IL-6, and tumour necrosis factor-α. Mechanistically, TGF-ß and TGFßRI levels were significantly upregulated in the lungs and kidneys of PQ-treated mice. Cellular thermal shift assay and western blotting revealed that AZ12601011 directly bound with TGFßRI and blocked the activation of Smad3 downstream. In conclusion, our findings revealed that AZ12601011 attenuated PQ-induced multiple organ fibrosis by blocking the TGF-ß/Smad3 signalling pathway, suggesting its potential for PQ poisoning treatment.

Design, synthesis and evaluation of a pyrazolo[3,4-d]pyrimidine derivative as a novel and potent TGFß1R1 inhibitor.

The transforming growth factor ß1 (TGFß1)/SMAD signaling pathway regulates many vital physiological processes. The development of potent inhibitors targeting activin receptor-like kinase 5 (ALK5) would provide potential treatment reagents for various diseases. A significant number of ALK5 inhibitors have been discovered, and they are currently undergoing clinical evaluation at various stages. However, the clinical demands were far from being met. In this study, we utilized an alternative conformation-similarity-based virtual screening (CSVS) combined with a fragment-based drug designing (FBDD) strategy to efficiently discover a potent and active hit with a novel chemical scaffold. After structural optimization in the principle of group replacement, compound 57 was identified as the most promising ALK5 inhibitor. Compound 57 demonstrated significant inhibitory effects against the TGF-ß1/SMAD signaling pathway. It could markedly attenuate the production of extracellular matrix (ECM) and deposition of collagen. Also, the lead compound showed adequate pharmacokinetic (PK) properties and good in vivo tolerance. Moreover, treatment with compound 57 in two different xerograph models showed significant inhibitory effects on the growth of pancreatic cancer cells. These results suggested that lead compound 57 refers as a promising ALK5 inhibitor both in vitro and in vivo, which merits further validation.

Gut microbiota regulates the ALK5/NOX1 axis by altering glutamine metabolism to inhibit ferroptosis of intrahepatic cholangiocarcinoma cells.

Intrahepatic cholangiocarcinoma (ICC) is a kind of hepatobiliary tumor that is increasing in incidence and mortality. The gut microbiota plays a role in the onset and progression of cancer, however, the specific mechanism by which the gut microbiota acts on ICC remains unclear. In this study, feces and plasma from healthy controls and ICC patients were collected for 16S rRNA sequencing or metabolomics analysis. Gut microbiota analysis showed that gut microbiota abundance and biodiversity were altered in ICC patients compared with controls. Plasma metabolism analysis showed that the metabolite glutamine content of the ICC patient was significantly higher than that of the controls. KEGG pathway analysis showed that glutamine plays a vital role in ICC. In addition, the use of antibiotics in ICC animals further confirmed that changes in gut microbiota affect changes in glutamine. Further experiments showed that supplementation with glutamine inhibited ferroptosis and downregulated ALK5 and NOX1 expression in HuCCT1 cells. ALK5 overexpression or NOX1 overexpression increased NOX1, p53, PTGS2, ACSL4, LPCAT3, ROS, MDA and Fe2+ and decreased FTH1, SLC7A11 and GSH. Knockdown of NOX1 suppressed FIN56-induced ferroptosis. In vivo, supplementation with glutamine promoted tumor growth. Overexpression of ALK5 repressed tumor growth and induced ferroptosis in nude mice, which could be reversed by the addition of glutamine. Our results suggested that the gut microbiota altered glutamine metabolism to inhibit ferroptosis in ICC by regulating the ALK5/NOX1 axis.

Advances in the discovery of activin receptor-like kinase 5 (ALK5) inhibitors.

Activin receptor­like kinase-5 (ALK5) is an outstanding member of the transforming growth factor-ß (TGF-ß) family. (TGF-ß) signaling pathway integrates pleiotropic proteins that regulate various cellular processes such as growth, proliferation, and differentiation. Dysregulation within the signaling pathway can cause variety of diseases, such as fibrosis, cardiovascular disease, and especially cancer, rendering ALK5 a potential drug target. Hence, various small molecules have been designed and synthesized as potent ALK5 inhibitors. In this review, we shed light on the current ATP-competitive inhibitors of ALK5 through diverse heterocyclic based scaffolds that are in clinical or pre-clinical phases of development. Moreover, we focused on the binding interactions of the compounds to the ATP binding site and the structure-activity relationship (SAR) of each scaffold, revealing new scopes for designing novel candidates with enhanced selectivity and metabolic profiles.

The Expression of Serglycin Is Required for Active Transforming Growth Factor ß Receptor I Tumorigenic Signaling in Glioblastoma Cells and Paracrine Activation of Stromal Fibroblasts via CXCR-2.

Serglycin (SRGN) is a pro-tumorigenic proteoglycan expressed and secreted by various aggressive tumors including glioblastoma (GBM). In our study, we investigated the interplay and biological outcomes of SRGN with TGFßRI, CXCR-2 and inflammatory mediators in GBM cells and fibroblasts. SRGN overexpression is associated with poor survival in GBM patients. High SRGN levels also exhibit a positive correlation with increased levels of various inflammatory mediators including members of TGFß signaling pathway, cytokines and receptors including CXCR-2 and proteolytic enzymes in GBM patients. SRGN-suppressed GBM cells show decreased expressions of TGFßRI associated with lower responsiveness to the manipulation of TGFß/TGFßRI pathway and the regulation of pro-tumorigenic properties. Active TGFßRI signaling in control GBM cells promotes their proliferation, invasion, proteolytic and inflammatory potential. Fibroblasts cultured with culture media derived by control SRGN-expressing GBM cells exhibit increased proliferation, migration and overexpression of cytokines and proteolytic enzymes including CXCL-1, IL-8, IL-6, IL-1ß, CCL-20, CCL-2, and MMP-9. Culture media derived by SRGN-suppressed GBM cells fail to induce the above properties to fibroblasts. Importantly, the activation of fibroblasts by GBM cells not only relies on the expression of SRGN in GBM cells but also on active CXCR-2 signaling both in GBM cells and fibroblasts.

Tgfbr1 controls developmental plasticity between the hindlimb and external genitalia by remodeling their regulatory landscape.

The hindlimb and external genitalia of present-day tetrapods are thought to derive from an ancestral common primordium that evolved to generate a wide diversity of structures adapted for efficient locomotion and mating in the ecological niche occupied by the species. We show that despite long evolutionary distance from the ancestral condition, the early primordium of the mouse external genitalia preserved the capacity to take hindlimb fates. In the absence of Tgfbr1, the pericloacal mesoderm generates an extra pair of hindlimbs at the expense of the external genitalia. It has been shown that the hindlimb and the genital primordia share many of their key regulatory factors. Tgfbr1 controls the response to those factors by modulating the accessibility status of regulatory elements that control the gene regulatory networks leading to the formation of genital or hindlimb structures. Our work uncovers a remarkable tissue plasticity with potential implications in the evolution of the hindlimb/genital area of tetrapods, and identifies an additional mechanism for Tgfbr1 activity that might also contribute to the control of other physiological or pathological processes.

TGF-ß1 induces PD-1 expression in macrophages through SMAD3/STAT3 cooperative signaling in chronic inflammation.

Programmed cell death protein 1 (PD-1), a coinhibitory T cell checkpoint, is also expressed on macrophages in pathogen- or tumor-driven chronic inflammation. Increasing evidence underscores the importance of PD-1 on macrophages for dampening immune responses. However, the mechanism governing PD-1 expression in macrophages in chronic inflammation remains largely unknown. TGF-ß1 is abundant within chronic inflammatory microenvironments. Here, based on public databases, significantly positive correlations between PDCD1 and TGFB1 gene expression were observed in most human tumors. Of note, among immune infiltrates, macrophages as the predominant infiltrate expressed higher PDCD1 and TGFBR1/TGFBR2 genes. MC38 colon cancer and Schistosoma japonicum infection were used as experimental models for chronic inflammation. PD-1hi macrophages from chronic inflammatory tissues displayed an immunoregulatory pattern and expressed a higher level of TGF-ß receptors. Either TGF-ß1-neutralizing antibody administration or macrophage-specific Tgfbr1 knockdown largely reduced PD-1 expression on macrophages in animal models. We further demonstrated that TGF-ß1 directly induced PD-1 expression on macrophages. Mechanistically, TGF-ß1-induced PD-1 expression on macrophages was dependent on SMAD3 and STAT3, which formed a complex at the Pdcd1 promoter. Collectively, our study shows that macrophages adapt to chronic inflammation through TGF-ß1-triggered cooperative SMAD3/STAT3 signaling that induces PD-1 expression and modulates macrophage function.

Blockade of endothelial adenosine receptor 2 A suppresses atherosclerosis in vivo through inhibiting CREB-ALK5-mediated endothelial to mesenchymal transition.

Cardiovascular diseases (CVDs) are the leading cause of death worldwide, and morbidity and mortality rates continue to rise. Atherosclerosis constitutes the principal etiology of CVDs. Endothelial injury, inflammation, and dysfunction are the initiating factors of atherosclerosis. Recently, we reported that endothelial adenosine receptor 2 A (ADORA2A), a G protein-coupled receptor (GPCR), plays critical roles in neovascularization disease and cerebrovascular disease. However, the precise role of endothelial ADORA2A in atherosclerosis is still not fully understood. Here, we showed that ADORA2A expression was markedly increased in the aortic endothelium of humans with atherosclerosis or Apoe-/- mice fed a high-cholesterol diet. In vivo studies unraveled that endothelial-specific Adora2a deficiency alleviated endothelial-to-mesenchymal transition (EndMT) and prevented the formation and instability of atherosclerotic plaque in Apoe-/- mice. Moreover, pharmacologic inhibition of ADORA2A with KW6002 recapitulated the anti-atherogenic phenotypes observed in genetically Adora2a-deficient mice. In cultured human aortic endothelial cells (HAECs), siRNA knockdown of ADORA2A or KW6002 inhibition of ADORA2A decreased EndMT, whereas adenoviral overexpression of ADORA2A induced EndMT. Mechanistically, ADORA2A upregulated ALK5 expression via a cAMP/PKA/CREB axis, leading to TGFß-Smad2/3 signaling activation, thereby promoting EndMT. In conclusion, these findings, for the first time, demonstrate that blockade of ADORA2A attenuated atherosclerosis via inhibition of EndMT induced by the CREB1-ALK5 axis. This study discloses a new link between endothelial ADORA2A and EndMT and indicates that inhibiting endothelial ADORA2A could be an effective novel strategy for the prevention and treatment of atherosclerotic CVDs.

Suramin inhibits phenotypic transformation of vascular smooth muscle cells and neointima hyperplasia by suppressing transforming growth factor beta receptor 1 /Smad2/3 pathway activation.

Vascular smooth muscle cells (VSMCs) contribute to neointimal hyperplasia (NIH) after vascular injury, a common feature of vascular remodelling disorders. Suramin is known to exert antitumour effects by inhibiting the proliferation of various tumour cells; however, its effects and mechanism on VSMCs remain unclear. This study investigated the effects of suramin on human aortic smooth muscle cells (HASMCs), rat aortic smooth muscle cells (RASMCs) and NIH to examine its suitability for the prevention of vascular remodelling disorders. In vitro, suramin administration reduced platelet-derived growth factor type BB (PDGF-BB)-stimulated proliferation, migration, and dedifferentiation of VSMCs through a transforming growth factor beta receptor 1 (TGFBR1)/Smad2/3-dependent pathway. Suramin dramatically inhibited NIH ligation in the left common carotid artery (LCCA) vivo. Therefore, our results indicate that suramin protects against the development of pathological vascular remodelling by attenuating VSMCs proliferation, migration, and phenotypic transformation and may be used as a potential medicine for the treatment of NIH.

HER2 phosphorylation induced by TGF-ß promotes mammary morphogenesis and breast cancer progression.

Transforming growth factor ß (TGF-ß) and HER2 signaling collaborate to promote breast cancer progression. However, their molecular interplay is largely unclear. TGF-ß can activate mitogen-activated protein kinase (MAPK) and AKT, but the underlying mechanism is not fully understood. In this study, we report that TGF-ß enhances HER2 activation, leading to the activation of MAPK and AKT. This process depends on the TGF-ß type I receptor TßRI kinase activity. TßRI phosphorylates HER2 at Ser779, promoting Y1248 phosphorylation and HER2 activation. Mice with HER2 S779A mutation display impaired mammary morphogenesis, reduced ductal elongation, and branching. Furthermore, wild-type HER2, but not S779A mutant, promotes TGF-ß-induced epithelial-mesenchymal transition, cell migration, and lung metastasis of breast cells. Increased HER2 S779 phosphorylation is observed in human breast cancers and positively correlated with the activation of HER2, MAPK, and AKT. Our findings demonstrate the crucial role of TGF-ß-induced S779 phosphorylation in HER2 activation, mammary gland development, and the pro-oncogenic function of TGF-ß in breast cancer progression.

Prognostic DNA mutation and mRNA expression analysis of perineural invasion in oral squamous cell carcinoma.

This study analyzed oral squamous cell carcinoma (OSCC) genomes and transcriptomes in relation to perineural invasion (PNI) and prognosis using Cancer Genome Atlas data and validated these results with GSE41613 data. Gene set enrichment analysis (GSEA), gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes were conducted. We identified 22 DNA mutations associated with both overall survival (OS) and PNI. Among them, TGFBR1 and RPS6KA4 mRNAs were overexpressed, while TYRO3 and GPR137 mRNAs were underexpressed in PNI patients. Among the 141 mRNA genes associated with both OS and PNI, we found overlap with PNI-related DNA mutations, including ZNF43, TEX10, TPSD1, and PSD3. In GSE41613 data, TGFBR1, RPS6KA4, TYRO3, GPR137, TEX10 and TPSD1 mRNAs were expressed differently according to the prognosis. The 22 DNA-mutated genes clustered into nervous system development, regulation of DNA-templated transcription, and transforming growth factor beta binding. GSEA analysis of mRNAs revealed upregulation of hallmarks epithelial mesenchymal transition (EMT), TNFα signaling via NF-κB, and IL2 STAT5 signaling. EMT upregulation aligned with the TGFBR1 DNA mutation, supporting its significance in PNI. These findings suggest a potential role of PNI genes in the prognosis of OSCC, providing insights for diagnosis and treatment of OSCC.

Familial visceral branch artery aneurysms in Loeys-Dietz syndrome.

Loeys-Dietz syndrome (LDS) is an autosomal dominant heritable disorder due to pathogenic variants in one of several genes involved in TGF-ß (transforming growth factor-beta) signalling. LDS is associated with aortic aneurysm and dissection. LDS may also lead to extra-aortic aneurysms, the majority of which occur in the head and neck vasculature. Visceral aneurysms are uncommon, and no cases of distal superior mesenteric artery (SMA) branch aneurysms in patients with LDS have been reported. Three related females with TGFBR1-related LDS developed distal SMA branch artery aneurysms involving the ileocolic and jejunal arteries. Endovascular or surgical intervention was performed in each. The presence and severity of arterial, craniofacial, and cutaneous features of LDS in these patients are variable. TGFBR1-related LDS may rarely lead to SMA branch artery aneurysms that can develop later in life. Surgical and endovascular procedures can successfully treat these aneurysms, but data to guide size thresholds and optimal treatment strategies are lacking.

Integrin ß8 prevents pericyte-myofibroblast transition and renal fibrosis through inhibiting the TGF-ß1/TGFBR1/Smad3 pathway in diabetic kidney disease.

Diabetic kidney disease (DKD) is one of the leading causes to develop end-stage kidney disease worldwide. Pericytes are implicated in the development of tissue fibrosis. However, the underlying mechanisms of pericytes in DKD remain largely unknown. We isolated and cultured primary pericytes and rat mesangial cells (HBZY-1). Western blot and qRT-PCR analysis were used to explore the role and regulatory mechanism of Integrin ß8/transforming growth factor beta 1 (TGF-ß1) pathway. We also constructed pericyte-specific Integrin ß8 knock-in mice as the research objects to determine the role of Integrin ß8 in vivo. We discovered that reduced Integrin ß8 expression was closely associated with pericyte transition in DKD. Overexpressed Integrin ß8 in pericytes dramatically suppressed TGF-ß1/TGF beta receptor 1 (TGFBR1)/Smad3 signaling pathway and protected glomerular endothelial cells (GECs) in vitro. In vivo, pericyte-specific Integrin ß8 knock-in ameliorated pericyte transition, endothelium injury and renal fibrosis in STZ-induced diabetic mice. Mechanistically, Murine double minute 2 (MDM2) was found to increase the degradation of Integrin ß8 and caused TGF-ß1 release and activation. Knockdown MDM2 could partly reverse the decline of Integrin ß8 and suppress pericytes transition. In conclusion, the present findings suggested that upregulated MDM2 expression contributes to the degradation of Integrin ß8 and activation of TGF-ß1/TGFBR1/Smad3 signaling pathway, which ultimately leads to pericyte transition during DKD progression. These results indicate MDM2/Integrin ß8 might be considered as therapeutic targets for DKD.

Sertoli Cell-Specific Activation of Transforming Growth Factor Beta Receptor 1 Leads to Testicular Granulosa Cell Tumor Formation.

The transforming growth factor ß (TGFß) superfamily, consisting of protein ligands, receptors, and intracellular SMAD transducers, regulates fundamental biological processes and cancer development. Our previous study has shown that sustained activation of TGFß receptor 1 (TGFBR1) driven by anti-Mullerian hormone receptor type 2 (Amhr2)-Cre in the mouse testis induces the formation of testicular granulosa cell tumors (TGCTs). As Amhr2-Cre is expressed in both Sertoli cells and Leydig cells, it remains unclear whether the activation of TGFBR1 in Sertoli cells alone is sufficient to induce TGCT formation. Therefore, the objective of this study was to determine whether Sertoli cell-activation of TGFBR1 drives oncogenesis in the testis. Our hypothesis was that overactivation of TGFBR1 in Sertoli cells would promote their transdifferentiation into granulosa-like cells and the formation of TGCTs. To test this hypothesis, we generated mice harboring constitutive activation of TGFBR1 in Sertoli cells using anti-Mullerian hormone (Amh)-Cre. Disorganized seminiferous tubules and tumor nodules were found in TGFBR1CA; Amh-Cre mice. A histological analysis showed that Sertoli cell-specific activation of TGFBR1 led to the development of neoplasms resembling granulosa cell tumors, which derailed spermatogenesis. Moreover, TGCTs expressed granulosa cell markers including FOXL2, FOXO1, and INHA. Using a dual fluorescence reporter line, the membrane-targeted tdTomato (mT)/membrane-targeted EGFP (mG) mouse, we provided evidence that Sertoli cells transdifferentiated toward a granulosa cell fate during tumorigenesis. Thus, our findings indicate that Sertoli cell-specific activation of TGFBR1 leads to the formation of TGCTs, supporting a key contribution of Sertoli cell reprogramming to the development of this testicular malignancy in our model.

Hypoxia-induced endothelial cell-derived exosome stimulates vascular smooth muscle cell proliferation and migration.

This study mainly used human VSMCs and ECs cultured in vitro to investigate whether exosomes (Exos) are involved in the communication between ECs and VSMCs under hypoxia, and to explore the role and mechanism of ECs-derived exosomes in the abnormal proliferation of VSMCs. VSMCs proliferation and migration were assessed by a series of cell function assays after culturing VSMCs alone or co-culturing ECs under hypoxia or normoxia. Next, exosomes were extracted from ECs under hypoxia or normoxia and characterized. We then introduced ECs-Exos to observe their effects on VSMCs proliferation and migration, and further evaluated the expression of transforming growth factor-beta receptor 1 (TGFBR1) pathway-related proteins. Finally, the effect of ECs-Exos on VSMCs function was evaluated after knocking down TGFBR1 in ECs. VSMCs treated with ECs-Exos exhibited increased proliferation and migration ability in hypoxic environment, and the expression of TGFBR1 pathway-related proteins was upregulated. Administration of ECs-Exos with TGFß1 knockdown conspicuously reversed the promoting effects of ECs-Exos on cell proliferation and migration under hypoxia. In summary, hypoxia affected the secretion of extracellular vesicles by endothelial cells, which can be internalized by VSMCs and accelerate the abnormal proliferation and migration of VSMCs by delivering TGFBR1.

Dual Inhibition of Mycobacterium tuberculosis and the Host TGFBR1 by an Anilinoquinazoline.

Tuberculosis (TB) control is complicated by the emergence of drug resistance. Promising strategies to prevent drug resistance are the targeting of nonreplicating, drug-tolerant bacterial populations and targeting of the host, but inhibitors and targets for either are still rare. In a cell-based screen of ATP-competitive inhibitors, we identified compounds with in vitro activity against replicating Mycobacterium tuberculosis (Mtb), and an anilinoquinazoline (AQA) that also had potent activity against nonreplicating and persistent Mtb. AQA was originally developed to inhibit human transforming growth factor receptor 1 (TGFBR1), a host kinase that is predicted to have host-adverse effects during Mtb infection. The structure-activity relationship of this dually active compound identified the pyridyl-6-methyl group as being required for potent Mtb inhibition but a liability for P450 metabolism. Pyrrolopyrimidine (43) emerged as the optimal compound that balanced micromolar inhibition of nonreplicating Mtb and TGFBR1 while also demonstrating improved metabolic stability and pharmacokinetic profiles.

Protocatechuic aldehyde increases pericyte coverage and mitigates pericyte damage to enhance the atherosclerotic plaque stability.

Pericyte dysfunction and loss contribute substantially to the destabilization and rupture of atherosclerotic plaques. Protocatechuic aldehyde (PCAD), a natural polyphenol, exerts anti-atherosclerotic effects. However, the effects and mechanisms of this polyphenol on pericyte recruitment, coverage, and pericyte function remain unknown. We here treated apolipoprotein E-deficient mice having high-fat diet-induced atherosclerosis with PCAD. PCAD achieved therapeutic effects similar to rosuvastatin in lowering lipid levels and thus preventing atherosclerosis progression. With PCAD administration, plaque phenotype exhibited higher stability with markedly reduced lesion vulnerability, which is characterized by reduced lipid content and macrophage accumulation, and a consequent increase in collagen deposition. PCAD therapy increased pericyte coverage in the plaques, reduced VEGF-A production, and inhibited intraplaque neovascularization. PCAD promoted pericyte proliferation, adhesion, and migration to mitigate ox-LDL-induced pericyte dysfunction, which thus maintained the capillary network structure and stability. Furthermore, TGFBR1 silencing partially reversed the protective effect exerted by PCAD on human microvascular pericytes. PCAD increased pericyte coverage and impeded ox-LDL-induced damages through TGF-ß1/TGFBR1/Smad2/3 signaling. All these novel findings indicated that PCAD increases pericyte coverage and alleviates pericyte damage to improve the stability of atherosclerotic plaques, which is accomplished by regulating TGF-ß1/TGFBR1/Smad2/3 signaling in pericytes.