Identifying phenolics by UPLC-MS/MS in some Prangos Lindl. species and α-glucosidase inhibitory activities

Diabetes mellitus is a chronic metabolic disorder associated with biochemical, physiological, and pathological changes in the liver and characterized by some deficiencies in insulin secretion or insulin action. Prangos Lindl. species are important plants used as spice and medicine in Asian countries, including Türkiye. This study first aimed to evaluate the antidiabetic potential of the aerial parts of the 5 different Prangos species (Apiaceae) collected from various locations to discover and identify bioactive phenolic components. The results revealed that the methanolic extract of P. heyniae exhibited the highest activity against α-glucosidase inhibition compared to the other Prangos species (IC50 = 458.54 ± 5.62 μg/mL). For this reason, the active species P. heyniae (an endemic species) was subjected to UPLC-MS/MS to evaluate the possible active phenolic components. The results showed that 53 phenolic compounds were correctly screened, 21 were precisely determined by UPLC-MS/MS in P. heyniae. Therefore, it was concluded that the aerial parts of P. heyniae might have therapeutic potential for hyperglycemia due to its phenolic compounds. Moreover, quinic acid (3.66%), chlorogenic acid (2.35%), rutin (2.96%), and hesperidin (0.79%) might be potential markers of the methanolic extract of P. heyniae. In the end, this study provides comprehensive knowledge regarding the phenolic profile of P. heyniae related to antidiabetic activity for the first time in this study.

BMPRII deficiency impairs apoptosis via the BMPRII-ALK1-BclX-mediated pathway in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a devastating cardiovascular disorder characterized by the remodelling of pre-capillary pulmonary arteries. The vascular remodelling observed in PAH patients results from excessive proliferation and apoptosis resistance of pulmonary arterial smooth muscle cells (PASMCs) and pulmonary arterial endothelial cells (PAECs). We have previously demonstrated that mutations in the type II receptor for bone morphogenetic protein (BMPRII) underlie the majority of the familial and inherited forms of the disease. We have further demonstrated that BMPRII deficiency promotes excessive proliferation and attenuates apoptosis in PASMCs, but the underlying mechanisms remain unclear. The major objective of this study is to investigate how BMPRII deficiency impairs apoptosis in PAH. Using multidisciplinary approaches, we demonstrate that deficiency in the expression of BMPRII impairs apoptosis by modulating the alternative splicing of the apoptotic regulator, B-cell lymphoma X (Bcl-x) transcripts: a finding observed in circulating leukocytes and lungs of PAH subjects, hypoxia-induced PAH rat lungs as well as in PASMCs and PAECs. BMPRII deficiency elicits cell specific effects: promoting the expression of Bcl-xL transcripts in PASMCs while inhibiting it in ECs, thus exerting differential apoptotic effects in these cells. The pro-survival effect of BMPRII receptor is mediated through the activin receptor-like kinase 1 (ALK1) but not the ALK3 receptor. Finally, we show that BMPRII interacts with the ALK1 receptor and pathogenic mutations in the BMPR2 gene abolish this interaction. Taken together, dysfunctional BMPRII responsiveness impairs apoptosis via the BMPRII-ALK1-Bcl-xL pathway in PAH. We suggest Bcl-xL as a potential biomarker and druggable target.

Cytotoxic naphthoquinones from Arnebia densiflora (Nordm.) Ledeb and determining new apoptosis inducers

In this study, phytochemical composition of Arnebia densiflora (AD) was determined and cytotoxic effects of the n-hexane extract and compounds isolated from this species on various cell lines were investigated. By means of serial chromatographic studies, 6 naphthoquinone derivatives were yielded, which are isovalerylalkannin, α-methyl-n-butyl alkannin, acetylalkannin, β-acetoxy isovalerylalkannin, alkannin and a new compound: 4-hydroxy 4-methyl valeryl alkannin. Structures of the isolated compounds were elucidated using UV, IR, 1D-2D NMR, MS and CD methods. Cytotoxic effects of the extract and isolated alkannins were investigated on L929, HeLa, HEp-2 cells. AD and the isolated compounds demonstrated moderate to strong cytotoxic effects (IC₅₀ range: 4.92-172.35 µg/ml). The results of DNA fragmentation and caspase-3 activity studies on HeLa cells exhibited that AD and the naphthoquinones isolated from it caused cytotoxicity through induction of apoptosis.[Formula: see text].