Chlorogenic acid (CGA) is a type of polyphenol compound found in rich concentrations in many plants such as green coffee beans. As an active natural substance, CGA exerts diverse therapeutic effects in response to a variety of pathological challenges, particularly conditions associated with chronic metabolic diseases and age-related disorders. It shows multidimensional functions, including neuroprotection for neurodegenerative disorders and diabetic peripheral neuropathy, anti-inflammation, anti-oxidation, anti-pathogens, mitigation of cardiovascular disorders, skin diseases, diabetes mellitus, liver and kidney injuries, and anti-tumor activities. Mechanistically, its integrative functions act through the modulation of anti-inflammation/oxidation and metabolic homeostasis. It can thwart inflammatory constituents at multiple levels such as curtailing NF-kB pathways to neutralize primitive inflammatory factors, hindering inflammatory propagation, and alleviating inflammation-related tissue injury. It concurrently raises pivotal antioxidants by activating the Nrf2 pathway, thus scavenging excessive cellular free radicals. It elevates AMPK pathways for the maintenance and restoration of metabolic homeostasis of glucose and lipids. Additionally, CGA shows functions of neuromodulation by targeting neuroreceptors and ion channels. In this review, we systematically recapitulate CGA’s pharmacological activities, medicinal properties, and mechanistic actions as a potential therapeutic agent. Further studies for defining its specific targeting molecules, improving its bioavailability, and validating its clinical efficacy are required to corroborate the therapeutic effects of CGA.

Trigonelline (TRG) is a natural polar hydrophilic alkaloid that is found in many plants such as green coffee beans and fenugreek seeds. TRG potentially acts on multiple molecular targets, including nuclear factor erythroid 2-related factor 2 (Nrf2), peroxisome proliferator-activated receptor γ, glycogen synthase kinase, tyrosinase, nerve growth factor, estrogen receptor, amyloid-β peptide, and several neurotransmitter receptors. In this review, we systematically summarize the pharmacological activities, medicinal properties, and mechanistic actions of TRG as a potential therapeutic agent. Mechanistically, TRG can facilitate the maintenance and restoration of the metabolic homeostasis of glucose and lipids. It can counteract inflammatory constituents at multiple levels by hampering pro-inflammatory factor release, alleviating inflammatory propagation, and attenuating tissue injury. It concurrently modulates oxidative stress by the blockage of the detrimental Nrf2 pathway when autophagy is impaired. Therefore, it exerts diverse therapeutic effects on a variety of pathological conditions associated with chronic metabolic diseases and age-related disorders. It shows multidimensional effects, including neuroprotection from neurodegenerative disorders and diabetic peripheral neuropathy, neuromodulation, mitigation of cardiovascular disorders, skin diseases, diabetic mellitus, liver and kidney injuries, and anti-pathogen and anti-tumor activities. Further validations are required to define its specific targeting molecules, dissect the underlying mechanistic networks, and corroborate its efficacy in clinical trials.

Port wine stain (PWS) is a congenital vascular malformation involving human skin. Approximately 15–20% of children a facial PWS involving the ophthalmic (V1) trigeminal dermatome are at risk for Sturge Weber syndrome (SWS), a neurocutaneous disorder with vascular malformations in the cerebral cortex on the same side of the facial PWS lesions. Recently, evidence has surfaced that advanced our understanding of the pathogenesis of PWS/SWS, including discoveries of somatic genetic mutations (GNAQ, PI3K), MAPK and PI3K aberrant activations, and molecular phenotypes of PWS endothelial cells. In this review, we summarize current knowledge on the etiology and pathology of PWS/SWS based on evidence that the activation of MAPK and/or PI3K contributes to the malformations, as well as potential futuristic treatment approaches targeting these aberrantly dysregulated signaling pathways. Current data support that: (1) PWS is a multifactorial malformation involving the entire physiological structure of human skin; (2) PWS should be pathoanatomically re-defined as “a malformation resulting from differentiation-impaired endothelial cells with a progressive dilatation of immature venule-like vasculatures”; (3) dysregulation of vascular MAPK and/or PI3K signaling during human embryonic development plays a part in the pathogenesis and progression of PWS/SWS; and (4) sporadic low frequency somatic mutations, such as GNAQ, PI3K, work as team players but not as a lone wolf, contributing to the development of vascular phenotypes. We also address many crucial questions yet to be answered in the future research investigations.

Coronavirus disease 2019 (COVID-19) patients show lipid metabolic alterations, but the mechanism remains unknown. In this study, we aimed to investigate whether the Spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) impairs lipid metabolism in host cells. We generated a Spike cell line in HEK293 using the pcDNA vector carrying the Spike gene expression cassette. A control cell line was generated using the empty pcDNA vector. Gene expression profiles related to lipid metabolic, autophagic, and ferroptotic pathways were investigated. Palmitic acid (PA)-overload was used to assess lipotoxicity-induced necrosis. As compared with controls, the Spike cells showed a significant increase in lipid depositions in cell membranes as well as dysregulation of expression of a panel of molecules involving lipid metabolism, autophagy, and ferroptosis. The Spike cells showed an upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2), a multifunctional transcriptional factor, in response to PA. Furthermore, the Spike cells exhibited increased necrosis in response to PA-induced lipotoxicity compared to control cells in a time- and dose-dependent manner via ferroptosis, which could be attenuated by the Nrf2 inhibitor trigonelline. We conclude that the Spike protein impairs lipid metabolic and autophagic pathways in host cells, leading to increased susceptibility to lipotoxicity via ferroptosis which can be suppressed by a Nrf2 inhibitor. This data also suggests a central role of Nrf2 in Spike-induced lipid metabolic impairments.

BACKGROUND: Small artery remodeling and endothelial dysfunction are hallmarks of hypertension. Evidence supports a likely causal association between cardiovascular diseases and endothelial-to-mesenchymal transition (EndMT), a cellular transdifferentiation process in which endothelial cells (ECs) partially lose their identity and acquire mesenchymal phenotypes. EC reprogramming represents an innovative strategy in regenerative medicine to prevent deleterious effects induced by cardiovascular diseases. METHODS: Using partial reprogramming of ECs, via overexpression of Oct-3/4-Sox-2-Klf-4 (OSK) transcription factors, we aimed to bring ECs back to a youthful phenotype in hypertension. Primary ECs were infected with lentiviral vectors (LVs) containing the specific EC promoter Cdh5 (cadherin-5) and the reporter EGFP (enhanced green fluorescent protein) with empty vector (LV control) or LV with Oct-3/4-Sox-2-Klf-4. Confocal microscopy and Western blotting analysis were used to confirm OSK overexpression. Cellular migration, senescence, and apoptosis were evaluated. Human aortic ECs from normotensive patients and patients with hypertension were analyzed after OSK treatments for eNOS (endothelial nitric oxide synthase), nitric oxide (NO), and genetic profile. Male and female normotensive (BPN/3J or blood pressure normal mouse strain) and hypertensive (BPH/2J or blood pressure high mouse strain) mice were treated with LV control or LV with Oct-3/4-Sox-2-Klf-4 and evaluated 10 days post-infection. The blood pressure, cardiac function, vascular reactivity of small arteries, and EndMT inhibition were analyzed. RESULTS: OSK overexpression induced partial EC reprogramming in vitro, and these cells had lower migratory capability. OSK treatment of BPH/2J mice reduced blood pressure and resistance arteries hypercontractility, via the attenuation of endothelial-to-mesenchymal transition and elastin breaks. EGFP was detected in vivo in the prefrontal cortex. OSK-treated hypertensive human aortic ECs showed high eNOS activation and NO production, with low reactive oxygen species (ROS) formation. Single-cell RNA analysis showed that OSK alleviated EC senescence and EndMT, restoring their phenotypes in human aortic ECs from patients with hypertension. CONCLUSIONS: Overall, these data indicate that OSK treatment and EC reprogramming can decrease blood pressure and reverse hypertension–induced vascular damage.

: Background: Port wine birthmark (PWB) is a congenital vascular malformation resulting from developmentally defective endothelial cells (ECs). Developing clinically relevant disease models for PWB studies is currently an unmet need. Objective: Our study aims to generate PWB-derived induced pluripotent stem cells (iPSCs) and iPSC-derived ECs that preserve disease-related phenotypes. Methods: PWB iPSCs were generated by reprogramming lesional dermal fibroblasts and differentiated into ECs. RNA-seq was performed to identify differentially expressed genes (DEGs) and enriched pathways. The functional phenotypes of iPSC-derived ECs were characterized by capillary-like structure (CLS) formation in vitro and Geltrex plug-in assay in vivo . Results: Human PWB and control iPSC lines were generated through reprogramming of dermal fibroblasts by introducing the “Yamanaka factors” (Oct3/4, Sox2, Klf4, c-Myc) into them; the iPSCs were successfully differentiated into ECs. These iPSCs and their derived ECs were validated by expression of a series of stem cell and EC biomarkers, respectively. PWB iPSC-derived ECs showed impaired CLS in vitro with larger perimeters and thicker branches as compared to control iPSC-derived ECs. In the plug-in assay, perfused human vasculature formed by PWB iPSC- derived ECs showed bigger perimeters and greater densities than those formed by control iPSC- derived ECs in severe combined immune deficient (SCID) mice. The transcriptome analysis showed that dysregulated pathways of stem cell differentiation, Hippo, Wnt, and focal adhesion persisted through differentiation of PWB iPSCs to ECs. Functional enrichment analysis showed that Hippo and Wnt pathway-related PWB DEGs are enriched for vasculature development, tube morphology, endothelium development, and EC differentiation. Further, members of the zinc finger (ZNF) gene family were overrepresented among the DEGs in PWB iPSCs. ZNF DEGs confer significant functions in transcriptional regulation, chromatin remodeling, protein ubiquitination, and retinoic acid receptor signaling. Furthermore, NF-kappa B, TNF, MAPK, and cholesterol metabolism pathways were dysregulated in PWB ECs as readouts of impaired differentiation. Conclusions: PWB iPSC-derived ECs render a novel and clinically-relevant disease model by retaining pathological phenotypes. Our data demonstrate multiple pathways, such as Hippo and Wnt, NF-kappa B, TNF, MAPK, and cholesterol metabolism, are dysregulated, which may contribute to the development of differentiation-defective ECs in PWB. Bulleted statements: What is already known about this topic?: Port Wine Birthmark (PWB) is a congenital vascular malformation with an incidence rate of 0.1 – 0.3 % per live births. PWB results from developmental defects in the dermal vasculature; PWB endothelial cells (ECs) have differentiational impairments. Pulse dye laser (PDL) is currently the preferred treatment for PWB; unfortunately, the efficacy of PDL treatment of PWB has not improved over the past three decades. What does this study add?: Induced pluripotent stem cells (iPSCs) were generated from PWB skin fibroblasts and differentiated into ECs. PWB ECs recapitulated their pathological phenotypes such as forming enlarged blood vessels in vitro and in vivo. Hippo and Wnt pathways were dysregulated in PWB iPSCs and ECs. Zinc-finger family genes were overrepresented among the differentially expressed genes in PWB iPSCs. Dysregulated NF-kappa B, TNF, MAPK, and cholesterol metabolism pathways were enriched in PWB ECs. What is the translational message?: Targeting Hippo and Wnt pathways and Zinc-finger family genes could restore the physiological differentiation of ECs. Targeting NF-kappa B, TNF, MAPK, and cholesterol metabolism pathways could mitigate the pathological progression of PWB. These mechanisms may lead to the development of paradigm-shifting therapeutic interventions for PWB.