MicroRNA miR-627-5p restrains pulmonary artery smooth muscle cell dysfunction by targeting MAP 2 K4 and PI3K/AKT signaling

The Bufei Nashen pill inhibits the PI3K/AKT/HIF-1 signaling pathway to regulate extracellular matrix deposition and improve COPD progression

ETHNOPHARMACOLOGICAL RELEVANCE

According to the theory and practice of traditional Chinese medicine (TCM), chronic obstructive pulmonary disease (COPD) can be classified as "cough," "dyspnea," or "lung distention disease." Bufei Nashen pill (BFNSP) is a classic Chinese herbal formula with certain activity against the above syndromes. FNSP has previously been shown to improve clinical symptoms (cough, lumbar and knee weakness, tinnitus) in patients with occupationally related interstitial lung disease.

AIM OF THE STUDY

There is a lack of convincing evidence supporting the use of BFNSP for the treatment of COPD. This study aimed to investigate the effect of BFNSP on COPD and explore its underlying mechanisms.

MATERIALS AND METHODS

Liquid chromatography-mass spectrometry (LC/MS) was used to analyze the main components of BFNSP and BFNSP-containing serum. A COPD rat model was generated, and the rats were treated with different doses of BFNSP. Lung function indices were analyzed by a pulmonary function testing system, and lung histopathology was assessed by HE staining and scanning electron microscopy. The levels of TGF-β1, IL-6, IL-8, IL-1β, MMP3, MMP-9, and TIMP1 in BALF and the levels of MMP3, MMP-9, TIMP1, and HA in serum were detected by ELISA. Immunohistochemical staining was performed to determine the expression of Col-I, Col-III, and LN in lung tissues. RT‒qPCR was performed to detect the mRNA expression of PI3K, Akt, HIF-1α, MMP-9, TGF-β1, TIMP1, and ERK1/2 in lung tissue, and Western blotting was performed to detect the protein expression of PI3K, p-PI3K, Akt, p-Akt, HIF-1α, MMP-9, TGF-β1, TIMP1, and p-ERK1/2 in lung tissue. In addition, in vitro cellular assays were performed for validation.

RESULTS

The results showed that BFNSP effectively improved the functional status of pulmonary ventilation, attenuated pathological damage in lung tissue, inhibited the release of inflammatory factors, reduced extracellular matrix deposition, and inhibited the activation of the PI3K/AKT/HIF-1 signaling pathway in lung tissue in COPD rats (P<0.05) and may alleviate COPD progression by inhibiting the PI3K/AKT/HIF-1 signaling pathway.

CONCLUSION

BFNSP inhibits the PI3K/AKT/HIF-1 signaling pathway to regulate extracellular matrix deposition and improve COPD progression.

CircST6GAL1 knockdown alleviates pulmonary arterial hypertension by regulating miR-509-5p/multiple C2 and transmembrane domain containing 2 axis

BACKGROUND

Hypertension is a main contributing factor of cardiovascular diseases; deregulated circular RNAs are involved in the pathogenesis of pulmonary arterial hypertension (PAH). Herein, we evaluated the function and mechanism of circST6GAL1 in PAH process.

METHODS

Human pulmonary artery smooth muscle cells (HPASMCs) were cultured in hypoxic environment for functional analysis. The cell counting kit-8, 5-ethynyl-2'-deoxyuridine, wound healing, and flow cytometry assays were used to investigate cell proliferation, migration, and apoptosis. qRT-PCR and Western blotting analyses were used for level measurement of genes and proteins. The binding between miR-509-5p and circST6GAL1 or multiple C2 and transmembrane domain containing 2 (MCTP2) was analyzed by dual-luciferase reporter, RNA immunoprecipitation, and pull-down assays. The monocrotaline (MCT)-induced PAH mouse models were established for in vivo assay.

RESULTS

CircST6GAL1 was highly expressed in PAH patients and hypoxia-induced HPASMCs. Functionally, circST6GAL1 deficiency reversed hypoxia-induced proliferation and migration, as well as apoptosis arrest in HPASMCs. Mechanistically, circST6GAL1 directly targeted miR-509-5p, and MCTP2 was a target of miR-509-5p. Rescue assays showed that the regulatory effects of circST6GAL1 deficiency on hypoxia-induced HPASMCs were abolished. Moreover, forced expression of miR-509-5p suppressed HPASMC proliferation and migration and induced cell apoptosis under hypoxia stimulation, while these effects were abolished by MCTP2 overexpression. Moreover, circST6GAL1 silencing improved MCT-induced pulmonary vascular remodeling and PAH.

CONCLUSION

CircST6GAL1 deficiency reversed hypoxia-induced proliferation and migration, as well as apoptosis arrest in HPASMCs, and alleviated pulmonary vascular remodeling in MCT-induced PAH mouse models through the miR-509-5p/MCTP2 axis, indicating a potential therapeutic target for PAH.

Characterization of exosomal microRNAs in preterm infants fed with breast milk and infant formula

Breastfeeding not only reduces infection-related morbidity, but also increases growth of preterm infants. Advantages of breast milk (BM) for preterm infants are significant. They continue to be studied. However, because not all preterm infants can receive breastfeeding, bovine-based infant formula (IF) is used as an alternative, which may increase the risk of several preterm complications. Exosomes isolated from biofluids are emerging as biomarkers in research of various diseases. Here, we characterized miRNA contents of exosomes in urine and serum samples of preterm infants who were BM and IF fed and performed transcriptomic analysis of small RNA libraries. We identified significantly up-regulated 6 miRNAs and 10 miRNAs, respectively. Gene Ontology (GO) analysis revealed that target genes of these miRNAs might participate in neuronal development, immunity modulation, detoxification of reactive oxygen species, and transmembrane exchange. Our data suggest that exosome-based systemic screening for preterm infants with breastfeeding might be a screening tool for identifying target molecules involved in therapy for preterm infants in neonatal intensive care unit (NICU) and for future application as nutraceutical formulations or pharmaceuticals.

The vascular perspective on acute and chronic lung disease

The pulmonary vasculature has been frequently overlooked in acute and chronic lung diseases, such as acute respiratory distress syndrome (ARDS), pulmonary fibrosis (PF), and chronic obstructive pulmonary disease (COPD). The primary emphasis in the management of these parenchymal disorders has largely revolved around the injury and aberrant repair of epithelial cells. However, there is increasing evidence that the vascular endothelium plays an active role in the development of acute and chronic lung diseases. The endothelial cell network in the capillary bed and the arterial and venous vessels provides a metabolically highly active barrier that controls the migration of immune cells, regulates vascular tone and permeability, and participates in the remodeling processes. Phenotypically and functionally altered endothelial cells, and remodeled vessels, can be found in acute and chronic lung diseases, although to different degrees, likely because of disease-specific mechanisms. Since vascular remodeling is associated with pulmonary hypertension, which worsens patient outcomes and survival, it is crucial to understand the underlying vascular alterations. In this Review, we describe the current knowledge regarding the role of the pulmonary vasculature in the development and progression of ARDS, PF, and COPD; we also outline future research directions with the hope of facilitating the development of mechanism-based therapies.