Can Arthrospira (Spirulina) sp. be used to protect the kidneys and prevent hypertension? a systematic review and meta-analysis of preclinical studies

Introduction: In Traditional Chinese Medicine (TCM), natural products such as Spirulina have been valued for centuries for their ability to regulate blood pressure and support organ function, including renal health. Arthrospira (Spirulina) sp., a blue-green cyanobacterium recognized by the United Nations as a ''superfood of the future,'' is rich in phycocyanin, a pigment with emerging nephroprotective potential. This review evaluates the effects of Spirulina or phycocyanin, alone or in combination with other bioactives, on biomarkers of kidney function. Methods: Systematic searches of databases like MEDLINE, Web of Science, LILACS, ScienceDirect, and CENTRAL between 2011 and 2024 are used to identify relevant studies for systematic reviews. The random-effect and inverse variance models were applied to verify data and perform meta-analysis. RoB tool for intervention studies (SYRCLE's RoB tool) and Cochrane Collaboration were used to assess quality and risk of bias. Results: A total of 267 studies were identified, and after screening, 10 were selected for analysis. Despite high heterogeneity across studies, the overall effects were statistically significant. Risk of bias was low across all domains, indicating reliable and robust findings. Discussion: The meta-analysis revealed that Arthrospira (Spirulina) and C-phycocyanin supplementation significantly improved biomarkers of kidney function, reducing serum creatinine, urea, uric acid, and urinary protein levels, as well as lowering systolic blood pressure in preclinical models. Despite consistent trends toward renoprotection and antihypertensive effects, high heterogeneity across studies highlights the need for further research to define optimal doses, treatment durations, and experimental conditions.