Insects as source of angiotensin converting enzyme inhibitory peptides

Hypertension is well known as one of the major risk for cardiovascular diseases which annually affect millions of people. The angiotensin converting enzyme (ACE) plays a key role in blood pressure regulation process. Indeed, hypertension treatment by synthetic ACE inhibitors (e.g. captopril, lisinopril and ramipril) is effective; however, their use can cause serious side effects, such as hypotension, cough, reduced renal function and angioedema. Thus, research was focused on natural ACE inhibitory peptides sources such as foodstuffs and also, more recently, edible insects In the last decades, ACE inhibitory activity has been detected in protein hydrolysates from insect species belonging to the orders of Coleoptera, Diptera, Hymenoptera, Lepidoptera and also Orthoptera. Further investigations led to identify specific ACE inhibitory peptides from the silkworm Bombyx mori (Lepidoptera: Bombycidae), the yellow mealworm Tenebrio molitor (Coleoptera: Tenebrionidae), the cotton leafworm Spodoptera littoralis (Lepidoptera: Noctuidae) and also from the weaver ant Oecophylla smaragdina (Hymenoptera: Formicidae). Even if ACE inhibitory activity of these bioactive peptides has been in vitro assayed and is comparable to those of some bioactive peptides derived from other animal protein sources, the in vivo effectiveness of most of these bioactive peptides still needs to be confirmed. The aim of this review is to present an outline of the currently available data on the potential use of insects for hypertension treatment with a focus on the ACE inhibitory peptides identified in these invertebrates to date.