Who hasn’t heard of Nutella®? This sweet hazelnut chocolate spread originated in Italy in 1964, and quickly became widely popular throughout Europe before making its first appearance in the USA in 1983. France is not only the world’s largest consumer of Nutella® , but also the world’s largest producer, and as a French girl raised on Nutella® breakfasts, I can attest to its delicious gooey sweetness and understand why Nutella has its own National Day (Feb 5th) and 2 unique Cafes (in NY and Chicago) for the ultimate Nutella® experience. But did you know that Nutella® has even reached the laboratory animals?
Nutella® in the Lab: Delivery Method for Bitter Medications
Patients taking buprenorphine have reported a bitter taste of the medication, so strong that it can even cause them to discontinue their treatment, giving us more understanding as to why even mice and rats turn their nose away from buprenorphine. However, in 2008, a collaborative scientific team in Sweden and Denmark used Nutella® to deliver buprenorphine to rats, and compare this route of administration with standard buprenorphine injections (PMID: 18596376). Over the course of the next 4 years, they published many other studies showing that oral delivery of buprenorphine via Nutella® is an effective analgesic strategy:
- Reduces stress from handling and restraint: lower corticosterone levels (PMID: 20952727)
- Increases welfare and recovery: high water consumption, maintenance of body weight and change of behavior (PMID: 20363983)
- Provides higher and prolonged buprenorphine concentrations in serum (PMID: 20837556)
They also demonstrated the efficiency of the method in mice (PMID: 21576406 and PMID: 20045358), and in 2012 presented the best way to implement the method, including a period of pre-habituation for up to 5 days, adequate amount, presentation and concentrations calculation (PMID: 22969145). In 2015, a team in Florida, USA showed that this method was also effective for tramadol, a narcotic analgesic with less adverse effects than opioids (PMID: 26817983).
Oral Buprenorphine: Efficient for Pain Management
In 2017, two additional studies were published using buprenorphine administered in Nutella®, demonstrating its significant antinociceptive effects (PMID: 27681372), using the hot plate test, in which an animal’s conscious removal of a body part from a heat source is used as a measure of nociception (1, 2). Additionally, buprenorphine did not interfere with the pathophysiology of a neuropathic pain model, or the development of allodynia (PMID: 29166664). Interestingly, repeated buprenorphine injections had depressive effects on food intake and body weight, underlining the welfare benefit of using oral delivery.
Buprenorphine delivery was also tested in our MediGel® Sucralose (PMID 25193176) and MediDrop® Sucralose (PMID 30674967), and while the serum concentrations of buprenorphine were similar to or higher than those after SC injection, the authors mentioned that willingness of the mice to ingest the gel needs to be improved. Because of the highly unpleasant taste of buprenorphine, we recommend using our MediGel® Hazelnut.
TYPES OF PAIN:
NOCICEPTION: pain sensitivity resulting from tissue injury
NEUROPATHIC PAIN: Pain caused by nerve irritation or injury
ALLODYNIA: pain elicited by a stimulus that normally does not cause pain
HYPERALGESIA: increased pain response produced by a stimulus that normally causes pain
Hot plate test
MediGel® Hazelnut as a Better Alternative to Nutella®
These studies demonstrated that Nutella® is able to mask the taste of unpleasant medications, is well-liked and readily ingested by rodents. However, Nutella® has a couple disadvantages: it is high in fat (29.7%) and sugar (56.7%), which may have undesirable effects in some experimental models, and it contains chocolate and thus, theobromine, which can be harmful and even toxic to animals!
ClearH2O’s MediGel® Hazelnut, is a better alternative for your lab animals:
- It is specifically formulated and packaged for use with laboratory mice and rats
- It is healthier than Nutella® with 8.2% fat and 44.6% sugar
- It is free from chocolate and theobromine
- It is made with purified ingredients including cane sugar, dry milk, hazelnut butter, cocoa butter and carob powder
- It has a highly palatable flavor that masks the unpleasant taste of various medications.