Protective Effects of Spirulina on Obesity-Induced Renal Damage and Oxidative Imbalance: Computational and Experimental Study

Background: Obesity, primarily driven by high-calorie and high-fat diets, is a major public health issue and a key risk factor for kidney dysfunction. It triggers glomerular hyperfiltration and oxidative stress, which can lead to chronic kidney disease (CKD). Spirulina has emerged as a potent natural agent with strong antioxidant and anti-inflammatory properties. Objectives: This study was conducted to evaluate the protective effects of spirulina (SP) against cafeteria diet (CD)-induced renal tissue alterations and oxidative stress in obese rats. Methods: Rats were divided into four groups and treated daily for eight weeks: the control group (standard diet (SD) 360 g/d), a cafeteria diet group (CD 360 g/d), a spirulina group (SP 500 mg/kg body weight (b.w.) administered orally (p.o.)), and a CD + SP group (500 mg/kg b.w., p.o.) We also performed an in silico molecular docking study with spirulina’s bioactive compound, phycocyanobilin. Results: Our findings showed that CD feeding led to an increase in body weight, kidney weight, and abdominal fat. In addition, severe renal alterations and disturbances in serum metabolic parameters associated with oxidative stress were observed in response to CD-induced obesity. However, SP administration significantly reduced body weight and total abdominal fat and improved lipid profiles. SP supplementation also notably improved oxidative status and protected against histological injury and disturbances. The in silico analysis predicted a favorable binding affinity of the phycocyanobilin compound for human CAT and GPx and a moderate predicted affinity for TNF-α and IL-6; these predictions are hypothesis-generating, as no direct target-engagement assays were performed. Conclusions: Taken together, these findings demonstrate the beneficial effects of SP on obesity induced by a cafeteria diet (CD), suggesting its potential in protecting against disturbances in renal function associated with oxidative stress and histological alterations.