Olive cake reduces glycaemia and lipemia and increases antioxidant enzymes in STZ-induced diabetes in rat erythrocytes and tissues

Abstract

Purpose The purpose of this study is to determine the effect of olive cake (CO) on glycaemia and lipemia and lipid peroxidation and antioxidant enzymes activities in erythrocytes and tissues, in streptozotocin (STZ)-induced diabetic rats. Design/methodology/approach Diabetes was induced by a single intraperitoneal injection of STZ (55 mg/kg BW). In total, 12 diabetic D rats, weighing 260 ± 20 g, were divided into two groups fed a casein diet supplemented (D-OC) or not (D) with OC (7.5 per cent), for four weeks. Findings In D-OC compared with D, glycaemia, total cholesterol and triglycerides values (−40 per cent; p = 0.007, 27 per cent; p = 0.007 and −27 per cent; p = 0.0019). In erythrocyte, liver, kidney, heart, muscle and brain, thiobarbituric acid reactive substances contents were respectively, (−19 per cent; p = 0.03, −32 per cent; p = 0.002, −20 per cent; p = 0.04, −68 per cent; p = 0.003, −74 per cent; p = 0.0003 and −38 per cent; p = 0.04). In erythrocyte, SOD, GSH-Px and CAT activities were respectively, (+14 per cent; p = 0.01, +74 per cent; p = 0.012 and +34 per cent; p = 0.0009). In the liver, kidney, heart and muscle, SOD activity was respectively, (+31 per cent; p = 0.004, +12 per cent; p = 0.038, +43 per cent; p = 0.001 and +23 per cent; p = 0.18). GSH-Px activity was respectively, (+121 per cent; p = 0.0009, 89 per cent; p = 0.0006, + 95 per cent; p = 0.008, +71 per cent; p = 0.02 and +26 per cent; p = 0.01), in the liver, kidney, heart, muscle and brain. Catalase activity was (+21 per cent; p = 0.008) in the liver, (+88 per cent; p = 0.0002 in the kidney, +53 per cent; p = 0,002 in the heart and 83 per cent; p = 0.00004 in the muscle). Originality/value In diabetic rats, OC reduces hyperglycaemia induced by STZ and attenuates triglyceridemia and cholesterolemia. This residue is able to decrease the oxidative stress by increasing the antioxidant enzymes activity in erythrocytes and tissues. The high contents of phytoconstituents present in OC are considered to be responsible for this effect.

Olive cake reduces obesity by decreasing epididymal adipocyte size, inhibiting oxidative stress and pancreatic lipase, in rat fed high fat diet

“…In our study, the HFD group showed a decrease in the exogenous and endogenous antioxidant, whereas the treatment of rats with OC increased the GSH level and the SOD, CAT and GPx activities. These results coincide with our previous study (Cherrad et al, 2020) and those of other researchers (Elkotb et al, 2017) where they showed the antioxidant activity of OC in diabetic rats. OC contains a large amount of dietary fiber and phenolic compound like polyphenols, flavonoids, anthocyanins, lignans and phenolic acids (Cea Pavez et al, 2019), which are known for their excellent antioxidant effect.…”

“…Our results revealed that OC administration reduced AST, ALT and AKP activities in obese rats, suggesting that this residue attenuated the liver damage caused by HFD. These findings are consistent with the results of Cherrad et al (2020), who reported a decrease in AST and ALT activities in diabetic rats treated with OC. In addition, Liu et al (2011) noted that olive pomace extract inhibited AST, ALT and AKP activities and ameliorated liver injury in hyperlipidemic rats induced by a high cholesterol diet.…”

“…It is a good source of minerals, dietary fiber, proteins, polyunsaturated fatty acids and phenolic compounds (Ribeiro et al , 2020),and it was used directly in the formulation of various food products to obtain high value-added healthy foods (Difonzo et al , 2021). In addition, it has been reported that OC possesses various biological function including, anti-inflammatory (Katsinas et al , 2021), antimicrobial (Ribeiro et al , 2020), antioxidant, antidiabetic (Cherrad et al , 2020; Zidan et al , 2020) and antihypercholesterolemic effects (Bouderbala et al , 2014). Our previous study using hypercholesterolemic rats have shown that the supplementation of the diet with OC decreased serum cholesterol, triglycerides and low-density lipoprotein cholesterol, increased high-density lipoprotein cholesterol, lowered liver lipids, prevent fatty liver and increased lipid excretion (Bouderbala et al , 2014).…”

Favorable effects ofGlobularia alypumon cardiometabolic markers in high fructose-fed rats

“…This dysregulation in glucose metabolism was ameliorated by supplementation of 1% of Ga in HF-D. Recently, Cherrad et al (2019), revealed that olive cake decreased hyperglycemia in streptozotocin-diabetic rats. But in fact, previous investigations of patients suffering from diabetes, have demonstrated that Ga represented the second highest percentage of medicinal plant consumption (9.9%) after Trigonellafoenum-graecum (13.3%) (Ziyyat et al , 1997).…”

Pickled olives neutralize vicine and convicine glycosides in Vicia faba and protect from favism

“…Moreover, Lins et al (2018) reported that olive leaf extract (an important source of natural antioxidants) was effective in antioxidant activity against different reactive species and protected human erythrocytes against oxidative damage. Furthermore, Cherrad et al (2020) and Zidan et al (2020) stated that olive cake decreased oxidative stress by increasing the antioxidant enzymes activity in erythrocytes, serum, liver, kidney, heart, muscle and brain tissues in diabetic rats.…”