Therapeutic Effect of EPA/DHA Supplementation in Neoplastic and Non-neoplastic Companion Animal Diseases: A Systematic Review

Abstract

Background/Aim: The aim of this study is to identify and describe randomized controlled studies evaluating the therapeutic effect of EPA and DHA supplementation in companion animal diseases. Materials and Methods: A systematic search was conducted in PubMed database and the information collected was summarized and evaluated according to the risk of bias, using the revised Cochrane tool (RoB2). Results: Twenty-three studies were eligible for inclusion: twenty performed in dogs and three in cats. A therapeutic benefit was found in canine allergic dermatitis, haircoat disorder, keratoconjunctivitis sicca, valvular disease, and canine and feline osteoarthritis. Dogs diagnosed with chronic heart failure and lymphoma and cats with allergic dermatitis also seem to benefit from supplementation with omega-3 fatty acids, but studies with improved methodological quality are needed to strengthen this evidence. Conclusion: EPA and DHA supplementation has proven benefits in the adjuvant treatment of various neoplastic and non-neoplastic diseases in dogs and cats.The use of nutraceuticals in the prevention and treatment of canine and feline diseases has been increasing as a result of a greater awareness of their effects by veterinarians. Omega-3 fatty acids are one of the most frequently prescribed products in small animal practices, mainly in the form of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (1).EPA and DHA are two types of omega-3 polyunsaturated fatty acids (PUFAs) that are derived from alpha-linolenic acid (ALA) through a metabolic pathway that includes chain elongation and desaturation. Since their bioconversion is very limited in dogs and cats, these omega-3 fatty acids need to be supplied to the animal through its diet (2, 3). The main source of EPA and DHA are fish and fish-oil products, such as menhaden, cod liver and salmon oils, even though crustaceans, bivalves, cephalopods and marine algae are also rich sources (4).Supplementation with EPA and DHA has shown benefits in the treatment of several human disorders, such as diabetes, cardiovascular problems, psychiatric and psychological disturbances, rheumatoid arthritis and even cancer (4). Regarding veterinary patients, inflammatory skin disorders, cardiovascular conditions, renal disease and osteoarthritis are the main non-neoplastic diseases where the EPA and DHA seem to have the most impact. Omega-3 fatty acid supplementation has also been used in adjuvant treatment of neoplastic diseases, however, the studies reported in these patients are more scarce (5). It is currently assumed that the benefit of these fatty acids is due to their immunomodulatory and lower-inflammatory effects because of its competitive 1419 This article is freely accessible online.

The Use of Egg and Egg Compounds in Companion Animal Health

“…Increased total dietary fat can contribute to coat gloss and softness, even if there is no fatty acid deficiency [121]. Atopic dogs benefit from supplemental omega-3 fatty acids reducing clinical signs of pruritus and inflammatory skin disease [122][123][124] including ALA and DHA added to diet. The immunomodulatory and lower-inflammatory effects of fatty acids act through competitive inhibition of the AA cascade with the final metabolites, prostaglandins, thromboxanes and leukotrienes, having a high pro-inflammatory activity [125] and omega-3 PUFA-derived lipid mediators [126].…”

Dietary omega‐3 fatty acids in the management of feline periodontal disease: What is the evidence?

“…According to a recent systematic review, the only feline disease in which EPA and DHA have a positive therapeutic effect with a strongly recognized evidence is feline osteoarthritis (Magalhães et al, 2021). Thus, as previously mentioned, there are no studies published to date regarding the effect of EPA and DHA on feline PD.…”

“…One of the main reasons may be the greater difficulty in oral administration of pills and capsules to cats, which compromises the owner's compliance (Freeman et al, 2006). Another possible explanation is the fact that there are fewer studies conducted in cats regarding the effect of supplementation, leading to less published evidence of its positive impact (Magalhães et al, 2021).…”

DHA-Provoked Reduction in Adipogenesis and Glucose Uptake Could Be Mediated by Gps2 Upregulation in Immature 3T3-L1 Cells

“…Various innovative strategies have been developed to partially reduce the damage caused by daily bad habits, with the role of omega-3 polyunsaturated fatty acids (PUFAs) in preventing obesity and related complications being of significant interest [4,5]. PUFAs, as well-known modulators of whole-body metabolism, are widely used in the therapeutic management of a range of inflammatory diseases and conditions, such as obesity, dermatitis, osteoarthritis, and cardiovascular comorbidities [6][7][8][9][10][11]. Among these fatty acids, docosahexaenoic acid (DHA) is of particular interest since, along with its anti-inflammatory and antiadipogenic features, it seems to have the ability to suppress the proliferation of rapidly dividing cells, making it a promising approach in cancer therapy [12][13][14].…”