Gout
Gout, sometimes referred to as gouty arthritis, is a form of arthritis characterized by an inflammatory response resulting from buildup of crystallized monosodium urate in the joints. Specifically, gout is a disorder of purine metabolism that causes elevated levels of serum uric acid in the bloodstream known as hyperuricemia. Hyperuricemia can lead to the formation and accumulation of monosodium urate crystals in various bodily tissues leading to acute attacks of arthritis.
Studies indicate that gout is the most prevalent form of arthritis observed in adults with an incidence rate of about 1.4%. There are numerous risk factors linked to the development of gout including genetics, gender, age and diet.
Unlike other types of arthritis, the causative agent of gout is known and this knowledge has led to development of valuable models for studying gout and the efficacy of test compounds for treatment.
WBI offers the following animal models for Human Gout:
MSU Air Pouch Gout Model
This model for human gout is built on the well-established Air Pouch Model in mice or rats. In the MSU Air Pouch Gout Model for inflammation, injection of sterile-filtered air under the skin on the back of the test animal provides an environment that is used to simulate the effects of diseases such as arthritis or gout.
Intra-articular (IA) Gout Models
In our IA Gout Model in Rat, monosodium urate crystals are administered into the knee joints by intra-articular (IA) injection to directly trigger joint inflammation and swelling characteristic of the disease. Male Wistar rats are anesthetized and receive intra-articular injection to the knee. Inflammation peaks on DAY 2 (MSU injection on DAY 0). Evaluation of test compound efficacy is determined by measurement of knee joint width using a digital caliper, compared to vehicle and control groups. Serum can be collected for additional testing, such as cytokine analysis or PK measurements. Knee tissue can also be collected for histopathology or shipment to client.
As a further evaluation of the disease state and treatment efficacy, pain measurements can be incorporated into the study protocol for responses to mechanical (Von Frey fibers) or thermal (Hargreaves test) stimuli.
WBI also offers an IA Gout Model in Rabbit in which female NZW rabbits are anesthetized and receive intra-articular injection to the knee. Knee inflammation peaks within 12 hours of MSU injection.
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Sources:
Annemans, L., Spaepen, E., Gaskin, M., Bonnemaire, M., Malier, V., Gilbert, T. and Nuki, G. (2007). Gout in the UK and Germany: prevalence, comorbidities and management in general practice 2000-2005. Annals of the Rheumatic Diseases, [online] 67(7), pp.960-966.
Anne-Kathrin Tausche, U. (2009). Gout - Current Diagnosis and Treatment. Deutsches Ärzteblatt International, [online] 106(34-35), p.549.