Microalgal Lipid Extracts Have Potential to Modulate the Inflammatory Response: A Critical Review

Abstract

Noncommunicable diseases (NCD) and age-associated diseases (AAD) are some of the gravest health concerns worldwide, accounting for up to 70% of total deaths globally. NCD and AAD, such as diabetes, obesity, cardiovascular disease, and cancer, are associated with low-grade chronic inflammation and poor dietary habits. Modulation of the inflammatory status through dietary components is a very appellative approach to fight these diseases and is supported by increasing evidence of natural and dietary components with strong anti-inflammatory activities. The consumption of bioactive lipids has a positive impact on preventing chronic inflammation and consequently NCD and AAD. Thus, new sources of bioactive lipids have been sought out. Microalgae are rich sources of bioactive lipids such as omega-6 and -3 polyunsaturated fatty acids (PUFA) and polar lipids with associated anti-inflammatory activity. PUFAs are enzymatically and non-enzymatically catalyzed to oxylipins and have a significant role in anti and pro-resolving inflammatory responses. Therefore, a large and rapidly growing body of research has been conducted in vivo and in vitro, investigating the potential anti-inflammatory activities of microalgae lipids. This review sought to summarize and critically analyze recent evidence of the anti-inflammatory potential of microalgae lipids and their possible use to prevent or mitigate chronic inflammation.

Keywords: anti-inflammatory; glycolipids; inflammation; lipids; microalgae; phospholipids.

Figure 1

The relationship and risk of noncommunicable diseases and age-associated diseases are increased by malnutrition originating from poor and unhealthy diets. Malnutrition promotes increased oxidative stress, DNA, cellular and tissue damage, and chronic inflammation. Chronic inflammation is associated with most NCDs and AADs. Bad diets are also associated with the unsustainable exploitation of resources, greenhouse gases (GHG) emissions, and impacts on climate change.

Figure 2

(A) Microalgae of different phyla were used in the assays to evaluate the anti-inflammatory activity of lipids. (B) Type of lipid extracts from microalgae used to assay the anti-inflammatory activity.

Figure 3

Main classes of polar lipids found in microalgae: glycerophospholipids (or phospholipids), glycoglycerolipids (or glycolipids), and betaine lipids.

Figure 4

Schematic representation of the anti-inflammatory potential of microalgae lipids. The scheme was based on the data collected and overviewed in Section 3. Microalgae crude lipid extracts, glycolipids, phospholipids, and other isolated lipids (e.g., oxylipins) displayed in vivo and in vitro anti-inflammatory activity with down-regulation of the pro-inflammatory mediators COX-2, iNOS, TNF-α, IL-6, and PAF.