ABSTRACT

Background and Aim: Plant-derived compounds have attracted interest as potential complementary approaches to feline glycemic management. However, evidence regarding the metabolic effects of Paederia foetida in cats remains limited. This study aimed to characterize the phenolic and flavonoid contents and in vitro antioxidant activity of P. foetida leaf extract and evaluate its effects on glycemic and lipid parameters in cats subjected to a mild dietary carbohydrate challenge.

Materials and Methods: Mature P. foetida leaves were extracted using 70% ethanol. Total phenolic and flavonoid contents were determined using colorimetric assays, and antioxidant activity was assessed using the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay. Eighteen clinically healthy cats participated in a non-randomized, one-sequence crossover study. Following control diet and high-carbohydrate-diet phases, all cats received glipizide (2.5 mg/cat/day) for 4 weeks, underwent a 4-week washout, and subsequently received P. foetida extract (500 mg/cat/day) for 4 weeks. Fasting blood glucose, intravenous glucose tolerance, serum triglycerides, and total cholesterol were evaluated.

Results: Total phenolic and flavonoid contents were 2.50 ± 0.33 mg gallic acid equivalents/g extract and 1.69 ± 0.50 mg quercetin equivalents/g extract, respectively. The extract exhibited relatively weak antioxidant activity, with a half-maximal inhibitory concentration of 2,000.00 ± 1.88 μg/mL. The high-carbohydrate diet increased fasting blood glucose from 85.3 ± 3.8 to 98.3 ± 4.3 mg/dL. Extract administration reduced fasting glucose to 88.1 ± 3.0 mg/dL (p < 0.05), whereas glipizide reduced it to 52.9 ± 7.7 mg/dL. Glucose tolerance improved following extract administration, although the response was less pronounced than with glipizide. Serum triglycerides were lower during extract treatment than during glipizide treatment, whereas the extract did not significantly reduce cholesterol relative to the high-carbohydrate-diet condition.

Conclusion: P. foetida leaf extract was associated with modest improvements in glycemic parameters in cats experiencing mild diet-induced blood glucose elevation. However, its antioxidant activity was limited, and its glucose-lowering effect was smaller than that of glipizide. Randomized studies that optimize dosing, standardize phytochemical characterization, and include longer-term monitoring are needed before establishing clinical applicability.

Keywords: antioxidant activity, feline glucose metabolism, glycemic regulation, high-carbohydrate diet, lipid profile, Paederia foetida, plant extract, sequential crossover study.