EC Pharmacology and Toxicology

Review Article Volume 14 Issue 6 - 2026

Transient Receptor Potential Canonical Channels and Sphingosine-1-Phosphate Signaling in Lung Vascular Endothelial Barrier Regulation: From Molecular Mechanisms to Therapeutic Opportunities

ustafa Mullah1, Mrunal Sathe1, Syed Hassan Balkhi2, Mohd Imran3, Zulfiqar Ahmad4, Madeeha Aqil5 and Mohammad Tauseef1*

1Foundational Sciences Discipline, Covenant HealthCare College of Medicine, Central Michigan University, Mount Pleasant, MI, USA
2Department of Pharmacology, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, India
3Center for Health Research, Northern Border University, Arar, Saudi Arabia
4Department of Biochemistry, Kirksville College of Osteopathic Medicine, A.T. Still University, Kirksville, MO, USA
5Freelance Medical Writer, Chicago, IL, USA

*Corresponding Author:Mohammad Tauseef, Associate Professor of Pharmacology, Covenant HealthCare College of Medicine at Central Michigan University, Mount Pleasant, MI, USA.
Received: April 22, 2026; Published: May 18, 2026



The pulmonary vascular endothelium serves as a dynamic, semi-permeable barrier that precisely governs the passage of fluid, solutes, and immune cells between the intravascular compartment and the surrounding alveolar tissue. Dysregulation of this barrier is the cardinal pathophysiological event in acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), life-threatening conditions characterized by non-cardiogenic pulmonary edema, refractory hypoxemia, and respiratory failure. Despite decades of intensive investigation, ARDS mortality remains unacceptably high - ranging from 30% to over 40% in severe cases - and no pharmacotherapy targeting endothelial barrier restoration has achieved regulatory approval. Central to endothelial barrier disruption is the elevation of intracellular calcium (Ca2+), which activates myosin light chain kinase (MLCK), drives actomyosin contraction, and ultimately disrupts intercellular adherens junctions (AJs). The transient receptor potential canonical (TRPC) family of non-selective cation channels - particularly TRPC1 and TRPC6 - mediates the primary Ca2+ entry events downstream of inflammatory stimuli including lipopolysaccharide (LPS)-Toll-like receptor 4 (TLR4) activation and thrombin-protease activated receptor-1 (PAR-1) signaling. TRPC6-dependent Ca2+ influx directly couples innate immune activation to lung vascular hyperpermeability and amplifies NF-κB-driven inflammatory gene transcription through a novel MLCK-MyD88IRAK4 signaling nexus. TRPC1, by contrast, operates as a constitutive suppressor of sphingosine kinase 1 (SPHK1), thereby setting the basal threshold for AJ stability. Counterbalancing this barrier-disruptive axis is the sphingosine-1-phosphate (S1P) signaling pathway. SPHK1-catalyzed generation of S1P, acting through its cognate receptor S1P1, potently activates Rac1 GTPase, promotes cortical actin assembly, stabilizes VE cadherin at AJs, and restores endothelial barrier integrity. SPHK1 is dynamically induced during the resolution phase of inflammatory barrier disruption, representing an endogenous vascular repair signal. Failure of this compensatory response - as observed in SPHK1 deficient animals - results in sustained, unresolved permeability increases and increased mortality. This comprehensive review synthesizes mechanistic, preclinical, and emerging clinical evidence for the functional interplay between TRPC channels and S1P signaling in the lung endothelium. We discuss the molecular architecture of the endothelial barrier, the upstream inflammatory triggers, the downstream effectors of barrier disruption and recovery, and the translational implications for therapeutic targeting in ARDS, sepsis, and COVID-19-associated endotheliopathy. We propose that pharmacological strategies directed at inhibiting TRPC6, amplifying SPHK1-S1P-S1P1 signaling, or simultaneously modulating both axes represent the most promising approaches to barrier-targeted therapy in inflammatory lung disease.

 Keywords: Endothelial Permeability; Acute Lung Injury; ARDS; Transient Receptor Potential Channel; Sphingosine-1-Phosphate; Adherens Junctions; Vascular Barrier; Sepsis

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Mohammad Tauseef., et al. “Transient Receptor Potential Canonical Channels and Sphingosine-1-Phosphate Signaling in Lung Vascular Endothelial Barrier Regulation: From Molecular Mechanisms to Therapeutic Opportunities”. EC Pharmacology and Toxicology 14.5 (2026): 01-22.

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