The Effects of Sinapic Acid on the Development of Metabolic Disorders Induced by Estrogen Deficiency in Rats

Abstract

Sinapic acid is a natural phenolic acid found in fruits, vegetables, and cereals, exerting numerous pharmacological effects. The aim of the study was to investigate the influence of sinapic acid on biochemical parameters related to glucose and lipid metabolism, as well as markers of antioxidant abilities and parameters of oxidative damage in the blood serum in estrogen-deficient rats. The study was performed on 3-month-old female Wistar rats, divided into 5 groups, including sham-operated control rats, ovariectomized control rats, and ovariectomized rats administered orally with estradiol (0.2 mg/kg) or sinapic acid (5 and 25 mg/kg) for 28 days. The levels of estradiol, progesterone, interleukin 18, insulin, glucose, fructosamine, lipids, and enzymatic and nonenzymatic antioxidants (superoxide dismutase, catalase, and glutathione); total antioxidant capacity; and oxidative damage parameters (thiobarbituric acid-reactive substances, protein carbonyl groups, and advanced oxidation protein products) were determined in the serum. Estradiol counteracted the carbohydrate and cholesterol metabolism disorders induced by estrogen deficiency. Sinapic acid increased the serum estradiol concentration; decreased insulin resistance and the triglyceride and total cholesterol concentrations; and favorably affected the parameters of antioxidant abilities (reduced glutathione, superoxide dismutase) and oxidative damage (advanced oxidation protein products).

Effect of Rosmarinic Acid and Sinapic Acid on Oxidative Stress Parameters in the Cardiac Tissue and Serum of Type 2 Diabetic Female Rats

“…Rosmarinic acid and sinapic acid administered to the type 2 diabetic rats at the higher doses (50 and 25 mg/kg respectively) lowered total cholesterol in the serum of the rats, similarly to rats in the early stage of estrogen deficiency [39,40]. Moreover, in our present study the higher doses of phenolic acids lowered the LDL-C in the serum of the type 2 diabetic rats.…”

“…The same doses for both the phenolic acids were used previously in ovariectomized rats. Both rosmarinic acid and sinapic acid lowered HOMA-IR in ovariectomized rats and rosmarinic acid additionally lowered fructosamine level in these rats [39,40]. In the current study, in which rats were in a permanent hyperglycemic state, neither rosmarinic acid nor sinapic acid affected the parameters connected with glucose metabolism.…”

Sinapic Acid Attenuates Cardiovascular Disorders in Rats by Modulating Reactive Oxygen Species and Angiotensin Receptor Expression

“…This finding is consistent with the results of Silambarasan et al, who observed that the hepatic and renal levels of total cholesterol in l-NAME rats with spontaneous hypertension were diminished after SA administration. The study by Zych et al [53] generated similar findings as well, with SA not only decreasing the levels of total cholesterol, triglycerides, and HOMA-IR index but also normalising certain serum markers of antioxidative capability and oxidative damage disrupted by oestrogen insufficiency in ovariectomised rats. Likewise, Gulcin [54] and Wilson et al [55] claimed that the levels of total cholesterol, triglycerides, LDL-C, and VLDL-C in the serum of rats with diabetes were significantly lowered by SA, while the level of HDL-C was heightened by SA.…”

Sinapic Acid Ameliorates the Progression of Streptozotocin (STZ)-Induced Diabetic Nephropathy in Rats via NRF2/HO-1 Mediated Pathways

“…SA treatment significantly inhibited both nitric oxide and lipid peroxidation in STZ induced DN rats. it was reported that SA caused a reduction in renal NO levels in injured rat kidneys ( Silambarasan et al., 2014 ; Zych et al., 2018 ). Christo et al.…”

“…"*" Indicates significant differences to the STZinduced diabetic group (P < 0.05); "#" indicates significant differences to the normal control. Zych et al, 2018). Christo et al (2011) showed that NO plays a role in DN due to the free radical nature of NO that contribute to tubular injuries.…”