Melanocortin-4 receptor and proopiomelanocortin: Candidate genes for obesity in domestic shorthair cats

Missense variants in MC4R gene are associated with obesity in cats

Obesity stands out as the most common multifactorial nutritional problem affecting domestic cats. According to studies, the prevalence of overweight or obese cats varies between 11.5% and 63%. Various factors such as breed, age, gender, reproductive status, owner-pet relationship, diet type, and environmental factors have been identified as potential risk factors for the development of obesity in cats. Among the genes involved in regulating energy balance, one of the prominent genes is melanocortin-4 receptor gene (MC4R). A specific missense variant in the feline MC4R gene (c.92 C > T) has been associated with overweight in diabetic domestic shorthaired cats. In this study, it was aimed to determine the polymorphisms in MC4R gene in random bred cats and cats belonging to a registered breed in Turkey and to investigate their relationship with obesity. Blood samples from 30 obese and 20 non-obese cats were collected into sterile vacuum EDTA tubes. Exon 1 of the MC4R was amplified and sequenced. As a result of DNA sequence analysis, we identified a total of six SNPs in the feline MC4R gene, four of which were found for the first time in this study. As a result of comparing allele frequencies in obese and non-obese cats, a significant relationship was found between SNP rs783632116 and obesity. The results of regression analyses evaluating the effects of SNP genotypes, sex and infertility status on feline Body Mass Index (fBMI) indicated that non-synonymous SNPs rs783632116, ss11356259660 and ss11356259661 were significantly associated with fBMI.

Evidence of obesity-induced inflammatory changes in client-owned cats

Background and Aim

Insulin resistance and type 2 diabetes mellitus are common health issues in obese (OB) cats. In humans, obesity leads to alterations in adipokine and proinflammatory cytokine secretion, causing persistent inflammation. The inflammatory impact of obesity in cats remains unproven. This study investigated associations between obesity and inflammatory and metabolic changes in three groups of client-owned Brazilian domestic shorthair cats: naturally lean, overweight (OW), and OB.

Materials and Methods

Cats from the Veterinary Hospital of Professor Sylvio Barbosa e Cardoso (FAVET/UECE) were clinically evaluated. Blood samples were collected for hematological and biochemical profile measurements, and part of the serum was used for measuring adipokine and inflammatory cytokines using sandwich enzyme-linked immunosorbent assay.

Results

In both the OW and OB groups, serum cholesterol and insulin concentrations increased, while triglyceride concentrations were notably elevated in the OB group. In the OW and OB groups, serum adiponectin, tumor necrosis factor-α, and interleukin-1β levels were elevated, and leptin levels were significantly higher in the OB group.

Conclusion

This study is the first in Brazil to reveal increased serum levels of inflammatory markers in OW and OB client-owned felines. OW cats exhibited higher proinflammatory marker levels, implying obesity-induced inflammation.

Embedding research and enquiry in Australian DVM curriculum

Research and enquiry (R&E) is an integral part of veterinary training. It is a foundation of evidence-based practice. In the University of Sydney Doctor of Veterinary Medicine degree R&E culminates in a cap-stone experience in Year 3: a 'professionally focused project', a student-driven and academic supported individual research project. The project provides an authentic experience within a veterinary discipline. Students work with an academic advisor who provides guidance for developing and achieving meaningful educational and professional goals. Successful advising depends upon a shared understanding of, and commitment to, the advising process by students, advisors and the university. The R&E mission can be broadly defined as - veterinarians recognise that evidence-based approach to practice, which is based on the scientific method, leads to the generation of new knowledge that underpins the veterinary medical profession.