Assessment of potential toxicological aspects of dietary exposure to silicon-rich spirulina in rats

Abstract

Silicon has beneficial effects especially on bones and skin and is important in cardiovascular pathophysiology. Furthermore, in spontaneously hypertensive rats, it reduces hypertension and increases antihypertensive and antiatherogenic gene expressions in the aorta. Thus, incorporating silicon into spirulina could be a way to produce a bioavailable food supplement. The potential toxic effects of silicon-rich spirulina (SES) through haematological and biochemical parameters and inflammatory and oxidative status were evaluated in rats' blood and liver tissue. The study consisted in a 90-day experiment on female and male rats supplemented with three doses (28.5, 57 and 285 mg/kg BW/day) of SES. No mortality, abnormal clinical signs, behavioural changes or macroscopic findings were observed whatever the groups. Haematological parameters were not modified in SES treated-groups. No marked change was recorded in biochemical parameters The liver endogenous antioxidant enzymes (SOD, GPx, catalase) activities were not modified whatever the gender and the dose, just as markers of oxidative stress (O2°(-), TBARS, thiols) and inflammation such as IL-6 and TNF-alpha. Our findings indicate that dietary supplementation of silicon-rich spirulina on rats has no harmful side nor toxic effects and could be beneficial especially in the case of suspicion or installation of pathologies due to oxidative stress.

Dietary Supplementation with Silicon-Enriched Spirulina Improves Arterial Remodeling and Function in Hypertensive Rats

“…However, only SpSi had beneficial effects on arterial function [19]. No toxicity or side effects of SpSi supplement were otherwise observed [28]. Increase of arterial stiffness, reduction of arterial compliance, and distensibility marked by fragmentation of elastin are the main consequences of arterial remodeling occurring in hypertension, obesity and aging [29].…”

Effect of spirulina and silicon‐enriched spirulina on metabolic syndrome features, oxidative stress and mitochondrial activity in Zucker fatty rats

“…The present work was designed to determine the potential effects of Sp and Sp+Si supplements on the major metabolic syndrome features, namely glucose intolerance and hepatic steatosis and their associated metabolic alterations, specifically inflammation, oxidative stress, and mitochondrial dysfunction, in a large chronic study of 12 weeks, in Zucker fatty rat. We have fixed these both doses of Sp and Si in a prelimiary study (Vidé, Romain, et al, ). The daily dose of Sp we supplied in the present study was 28.5 mg/kg, which represents 2 g of Sp/day for un adulte of 70 kg.…”

“…The rats of each group received a placebo croquette (Zucker group), a Sp croquette (28.5 mg/kg body weight, Zucker+Sp group), or a Sp+Si croquette (28.5 mg Sp with 0.57 mg Si/kg body weight, Zucker+Sp+Si group). Sp dosage and its Si content (2%) were determined according to previous studies (Vidé, Romain, et al, ) and this corresponds to daily intake of about 2,000 mg of Sp and 40 mg of Si for a 70 kg‐human (Reagan‐Shaw, Nihal, & Ahmad, ). Zucker rats were given free access to tap water and food and their body weight and food consumption were recorded weekly.…”