Phospholipid cell membrane

The phospholipid cell membrane is a fundamental biological structure composed of a lipid bilayer that serves as a semi-permeable barrier for all living cells. It consists primarily of amphiphilic phospholipids, cholesterol, and embedded proteins, maintaining cellular integrity and regulating the movement of substances in and out of the cell (Alberts et al., Molecular Biology of the Cell). Beyond its structural role, the membrane is a critical site for signal transduction and ion homeostasis. In pharmacology, the membrane itself serves as a direct therapeutic target, particularly for antimicrobial and antifungal agents like polymyxins and polyenes. These drugs exploit differences in lipid composition, such as the presence of ergosterol in fungi or specific anionic lipids in bacteria, to induce membrane permeabilization and cell death (StatPearls, 2023). However, targeting the membrane presents significant challenges in drug design, as maintaining selectivity for pathogen membranes over human host membranes is essential to minimize systemic toxicities. Notable adverse effects associated with membrane-disrupting drugs include nephrotoxicity and hemolysis (PubMed, PMID: 30244133). Emerging research also explores the role of membrane lipid composition in cancer and neurodegenerative diseases, suggesting the membrane as a potential target for modulating cell signaling in these conditions.

Other names

Plasma membraneLipid bilayerCytoplasmic membraneCell membrane

Drugs targeting the phospholipid cell membrane typically act by disrupting the physical integrity of the bilayer. This includes the formation of transmembrane pores, induction of rapid depolarization through ion leakage, or alteration of membrane fluidity and curvature (StatPearls, 2023; PubMed, PMID: 27337101). In the case of antifungal and antibacterial agents, selectivity is often achieved by targeting specific lipid components, such as ergosterol in fungi or anionic phospholipids in bacteria, that differ from those in human host cells (NIH, 2022).