Coenzyme Q10: Novel Formulations and Medical Trends

Abstract

The aim of this review is to shed light over the most recent advances in Coenzyme Q10 (CoQ10) applications as well as to provide detailed information about the functions of this versatile molecule, which have proven to be of great interest in the medical field. Traditionally, CoQ10 clinical use was based on its antioxidant properties; however, a wide range of highly interesting alternative functions have recently been discovered. In this line, CoQ10 has shown pain-alleviating properties in fibromyalgia patients, a membrane-stabilizing function, immune system enhancing ability, or a fundamental role for insulin sensitivity, apart from potentially beneficial properties for familial hypercholesterolemia patients. In brief, it shows a remarkable amount of functions in addition to those yet to be discovered. Despite its multiple therapeutic applications, CoQ10 is not commonly prescribed as a drug because of its low oral bioavailability, which compromises its efficacy. Hence, several formulations have been developed to face such inconvenience. These were initially designed as lipid nanoparticles for CoQ10 encapsulation and distribution through biological membranes and eventually evolved towards chemical modifications of the molecule to decrease its hydrophobicity. Some of the most promising formulations will also be discussed in this review.

Keywords: Coenzyme Q10; mitochondria; ubiquinone.

Conflict of interest statement

The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Figures

Figure 1

CoQ10 applications in the medical field. Traditionally, CoQ10 has been used as a therapeutic agent for diabetic cardiovascular diseases, diabetic nephropathy, neuroprotection, and heart failure owing to its antioxidant activity. In fact, it is widely known that the excessive generation of ROS is a common underlying factor of all these diseases which severely worsens the outcome for the patients. More recently, several studies have proved CoQ10’s potential application against ultraviolet B (UVB) radiation damage, multiple system atrophy (MSA), or as an immunity and inflammatory marker. Both in MSA and inflammation, CoQ10 levels are below the normal range in patients, the reason why its supplementation led to an improvement in their development and well-being. Furthermore, due to its ROS-scavenging function, CoQ10 has proved to be significantly beneficial for skin cells’ protection against UVB radiation and insulin sensitivity. Surprising though it may seem, it is also highly beneficial for familial hypercholesterolemia patients who, in general, present a secondary CoQ10 deficiency derived from their disease. Finally, it has shown a remarkable membrane stabilizing property, since it increases the lipid packing order and the mechanical stability of the IMM-mimicking membranes, the reason why it could potentially be used as a therapy for Barth syndrome patients.

Figure 2

Highlights of CoQ10 formulations. The initial trend in CoQ10 formulations’ design was to use non-polar agents as delivery systems due to several advantages they present (increase drug solubility in intestines, recruit lymphatic drug transport, or modify enterocyte-based drug transport and disposition). However, there is rising interest in the development of water-soluble delivery mechanisms in order to prevent the common drawbacks of lipid-based formulations, such as rate of dispersion, degree of emulsification, particle size, or drug precipitation from the formulation upon dispersion. The first attempts towards this goal include the development of lipid-free CoQ10 nanoformulations, micellar CoQ10 solutions, and hydrophilic CoQ10 inclusion complexes.