Antimicrobial Activity of Host-Derived Lipids

Abstract

Host-derived lipids are increasingly recognized as antimicrobial molecules that function in innate immune activities along with antimicrobial peptides. Sphingoid bases and fatty acids found on the skin, in saliva and other body fluids, and on all mucosal surfaces, including oral mucosa, exhibit antimicrobial activity against a variety of Gram positive and Gram negative bacteria, viruses, and fungi, and reduce inflammation in animal models. Multiple studies demonstrate that the antimicrobial activity of lipids is both specific and selective. There are indications that the site of action of antimicrobial fatty acids is the bacterial membrane, while the long-chain bases may inhibit cell wall synthesis as well as interacting with bacterial membranes. Research in this area, although still sporadic, has slowly increased in the last few decades; however, we still have much to learn about antimicrobial lipid mechanisms of activity and their potential use in novel drugs or topical treatments. One important potential benefit for the use of innate antimicrobial lipids (AMLs) as antimicrobial agents is the decreased likelihood side effects with treatment. Multiple studies report that endogenous AML treatments do not induce damage to cells or tissues, often decrease inflammation, and are active against biofilms. The present review summarizes the history of antimicrobial lipids from the skin surface, including both fatty acids and sphingoid bases, in multiple human body systems and summarizes their relative activity against various microorganisms. The range of antibacterial activities of lipids present at the skin surface and in saliva is presented. Some observations relevant to mechanisms of actions are discussed, but are largely still unknown. Multiple recent studies examine the therapeutic and prophylactic uses of AMLs. Although these lipids have been repeatedly demonstrated to act as innate effector molecules, they are not yet widely accepted as such. These compiled data further support fatty acid and sphingoid base inclusion as innate effector molecules.

Circulating short and medium chain fatty acids are associated with normoalbuminuria in type 1 diabetes of long duration

“…MCFAs have well-documented antimicrobial properties 30 , and research has suggested they may reduce inflammation 31 and provide more readily available energy in the mitochondria than LCFAs 32 . When it comes to potential sources of MCFAs, studies point to gut microbial species or dairy intake 25,[33][34][35][36] .…”

Profiling and Role of Bioactive Molecules from Puntius sophore (Freshwater/Brackish Fish) Skin Mucus with Its Potent Antibacterial, Antiadhesion, and Antibiofilm Activities

“…They function in innate immune response along with peptides and are found on skin, saliva, and mucosal surfaces including other body fluids. Their possible mode of action is inhibition of cell wall synthesis and interfering with the bacterial membrane [ 44 ]. Another important detection in fish epidermal mucus is the occurrence of short peptides which are also known for antimicrobial and antibiofilm activities [ 14 , 83 , 84 , 85 , 86 , 87 , 88 ].…”

Microbiome Profile in Adult Balanoposthitis Patients: Relationship with Redundant Prepuce, Skin Physical Barrier Status and Inflammation

“…The cutaneous microbiome can be in uenced by physio-barrier integrity, in ammation, antimicrobial peptides, and even lipids, as reported in atopic dermatitis [16,17]. The thin epithelium of prepuce and glans penis have similarities to other parts of the skin, except that there was no hair follicle or eccrine sweat gland exist on glans penis, penis crown, and preputial mucosa [18].…”