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The objectives of the present investigation were to: (1) elucidate the transport mechanism of paeoniflorin (PF) across MDCK-MDR1 monolayers; and (2) evaluate the effect of ligustilide (LIG), senkyunolide I (SENI) and senkyunolide A (SENA) on the transport of PF through blood-brain barrier so as to explore the enhancement mechanism. Transport studies of PF were performed in both directions, from apical to basolateral side (A→B) and from basolateral to apical sides (B→A). Drug concentrations were analyzed by LC-MS/MS. PF showed relatively poor absorption in MDCK-MDR1 cells, apparent permeability coefficients (Papp) ranging from 0.587 × 10(-6) to 0.705 × 10(-6) cm/s. In vitro experiments showed that the transport of PF in both directions was concentration dependent and not saturable. The B→A/A→B permeability ER of PF was more than 2 in the MDCK-MDR1 cells, which indicated that the transport mechanism of PF might be passive diffusion as the dominating process with the active transportation mediated mechanism involved. The increased Papp of PF in A→B direction by EDTA-Na₂ suggested that PF was absorbed via the paracellular route. The P-gp inhibitor verapamil could significantly increase the transport of PF in A→B direction, and ER decreased from 2.210 to 0.690, which indicated that PF was P-gp substance. The transport of PF in A→B direction significantly increased when co-administrated with increasing concentrations of LIG, SENI and SENA. An increased cellular accumulation of Rho 123 and Western blot analysis indicated that LIG, SENI and SENA had increased the transport of PF in the BBB models attribute to down-regulate P-gp expression. A decrease in transepithelial electrical resistance (TEER) during the permeation experiment can be explained by the modulation and opening of the tight junctions caused by the permeation enhancer LIG, SENI and SENA.
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http://dx.doi.org/10.3390/molecules21030300 | DOI Listing |
Channels (Austin)
December 2025
Biorheology Research Laboratory, Faculty of Health, Griffith University, Gold Coast, Australia.
The hallmarks of mechanosensitive ion channels have been observed for half a century in various cell lines, although their mechanisms and molecular identities remained unknown until recently. Identification of the bona fide mammalian mechanosensory Piezo channels resulted in an explosion of research exploring the translation of mechanical cues into biochemical signals and dynamic cell morphology responses. One of the Piezo isoforms - Piezo1 - is integral in the erythrocyte (red blood cell; RBC) membrane.
View Article and Find Full Text PDFSci Adv
September 2025
Laoshan Laboratory, Qingdao, China.
Anthropogenic aerosols are an important driver of historical climate change but the climate response is not fully understood and the climate model simulations suffer large uncertainties. On the basis of a multimodel ensemble of historical aerosol forcing simulation for a period of global aerosol increase during 1965 to 1989, here, we show that the precipitation response shares a common southward displacement of tropical rain bands but the magnitude differs markedly among models, accounting for 76% of the intermodel uncertainty in zonal-mean precipitation change. Our analysis of atmospheric energetics further reveals key mechanisms for magnitude uncertainty: aerosol radiative forcing drives, cloud radiative feedback amplifies, and ocean circulation damps the intermodel uncertainty in cross-equatorial atmospheric energy transport change and the meridional shift of tropical rain bands.
View Article and Find Full Text PDFPhys Rev Lett
August 2025
University of Konstanz, Department of Physics and Center for Applied Photonics, D-78457 Konstanz, Germany.
Femtosecond laser excitation of nanometer thin heterostructures comprising a heavy metal and a magnetically ordered material is known to result in the emission of terahertz radiation. However, the nature of the emitted radiation from heavy metal/antiferromagnet heterostructures has sparked debates and controversies in the literature. Here, we unambiguously separate spin and charge contributions from Pt/NiO heterostructures by introducing an unprecedented methodology combining high external magnetic fields with a symmetry analysis of the emitted terahertz polarization.
View Article and Find Full Text PDFPhys Rev Lett
August 2025
Duke University, Thomas Lord Department of Mechanical Engineering and Materials Science, Durham, North Carolina 27708, USA.
Chiral phonons, which are characterized by rotational atomic motion, offer a unique mechanism for transferring angular momentum from phonons to electron spins and other angular momentum carriers. In this Letter, we present a theoretical investigation into the emergence of chiral phonons in a chiral hybrid organic-inorganic perovskite (HOIP) and their critical roles in rigid-body rotation, magnetic moment generation, and spin transport under nonthermal equilibrium conditions. We demonstrate that phonon angular momentum can modify the spin chemical potential via a proposed microscopic Barnett effect, leading to a spatially varying spin chemical potential at the metal/HOIP interface, which subsequently induces spin currents in an adjacent Cu layer, with a magnitude consistent with experimental observations.
View Article and Find Full Text PDFAm J Physiol Cell Physiol
September 2025
Division of Gastroenterology & Hepatology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Chronic diarrhea is a frequent gastrointestinal complication in both type 1 (T1D) and type 2 diabetes (T2D), although the underlying mechanisms differ: T1D is linked to autonomic neuropathy and disrupted transporter regulation, while T2D is often linked to medications and intestinal inflammation. Using streptozotocin-induced mouse models of T1D and T2D, we observed increased luminal fluid in the small intestine of both. Given the role of Na⁺/H⁺ exchanger 3 (NHE3) in fluid absorption and its loss in most diarrheal diseases, we examined NHE3 expression across intestinal segments.
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