As shown in Table (3): In this investigation administration of lithogenic substances such as ethylene glycol (EG) in rats showed impaired renal function with increase P, Ca and ox. Stone formation in ethylene glycol is caused by hyperoxaluria, which causes increased renal retention and excretion of oxalate
(Mandavia et al., 2013). Two types of kidney stones, calcium oxalate crystal forms when calcium combines with oxalic acid, Calcium phosphate stone crystals form when calcium atoms combine with phosphoric acid instead of oxalic acid and produce the calcium phosphate kidney stone. Calcium phosphate kidney stone tends to occur in people who produce more alkaline urine than those who produce calcium oxalate kidney stones
(Callaghan and Bandyopadhyay 2012). Additionally, a high-phosphorus diet caused kidney stone formation
(Bushinsky et al., 2000). Alterations in phosphorus homeostasis also may contribute to calcium kidney stones. Studies to date of calcium and phosphorus regulatory hormones and nephrolithiasis have been cross-sectional and focused on urine factors rather than actual kidney stone formation
(Taylor et al., 2015).
Calcium oxalate crystal deposition is associated with severe oxidative stress to renal tissue. It leads to lipid peroxidation of membranes by the generation of reactive oxygen species
(Khan 2004). Our result is coincidence with the previous study of
(Velpandian et al., 2012) and
(Liu et al., 2018) they reported that hyperoxaluria and crystal deposition induced the production of ROS and renal epithelial cells injury in a rat model of calcium oxalate nephrolithiasis. This finding was confirmed by urine examination as shown in Fig 1 (b) show a high density of CaOx crystals. Administration of
Orobanche (EG+OR) significantly reduced (P<0.05) P, Ca and OX, Suggesting, the antiurolithiasis activity of
Orobanche has been attributed to the high phenolic contents and particularly flavonoids have antiurolithiasis activity responsible for the reduction of CaOx crystal aggregation
Zeng and Jiang (2019). Similarly, EG+CYT treated group significantly reduces P, Ca and OX. These results support the use of
Orobanche extract as an effective alternative in treating ethylene glycol induced urolithiasis. This result was confirmed by urine examination as shown in Fig 1 (D and E) treatment with Cystone or
Orobanche reduce the risk of stone formation.
Microscopic Examination
As shown in Table (4) there was a significant increase (P<0.05) in urea and creatinine in ethylene glycol group compared to the control group the elevated urea and creatinine levels in serum indicated a diminished renal function in hyperoxaluric conditions. Our results are in line with previous studies
(Aggrawal et al., 2012 and
kumari et al., 2016). They showed that urea and creatinine levels in serum were elevated due to EG. However administrated of
Orobanche extract (EG +OR) significantly reduced (P<0.05) level of urea and creatinine by improving glomerular filtration which indicates that
Orobanche exerts nephroprotective effect this effect may be due to presence phytoconstituents such as flavonoid, phenolic acid Vanillic acid, Glucopyranose terpenes some earlier reports show that flavonoid-rich plants extracts possess antiurolithiatic activity
(Ahmed et al., 2013). These results were coincidence with an earlier study of
(Sindu et al., 2015) who reported that rats treated with vanillic acid (50mg/kg and 100mg/kg) restored the elevated levels of renal function markers and reduced antioxidant status to near normalcy. Severe hepatic damages were observed by significant elevation of hepatic enzymes ALT, AST and bilirubin activity in the serum of ethylene glycol group as shown in Table (4) this finding were in accordance with other studies of (El
Sawy et al., 2014 and
kumari et al., 2016) they recorded elevation in ALT and AST enzymes, the elevated levels of hepatic enzymes activities may indicate liver tissue damage probably by altered cell membrane permeability leading to the leakage of enzymes from tissue to the serum. Administration of
Orobanche significantly reduce the elevations in the liver enzyme, this result was coincidence with an earlier study of
(Itoh et al., 2010) who showed that phenolic acid such as vanillic acid suppressed the transaminase enzyme.
As shown in Table (5) there was a significant elevation (P<0.05) in the MDA level in kidney tissue associated with a significant decrease in glutathione peroxidase compared to the control group. The elevated concentration of MDA in the EG group is indicative of oxidative tissue damage, as lipid peroxides. It seems clear that renal epithelial cell injury plays a vital role in calculus development and the lithogenic effect of EG must be mainly attributed to the oxidative damage induced by high levels of oxalate generated by ethylene glycol, decreased tissue antioxidant enzymes may be followed by elevated free radical production in the early stages and in the later stages of nephrolithiasis, which may put the renal tissue under oxidative stress
(Thamilselvan et al., 2003). These results are coincidence with the previous study of
(Karadi et al., 2006; Khan 2014);
(Golshan et al., 2017), they reported that administration of ethylene glycol induced oxidative stress. Increase glutathione peroxidase (GPx) in
Orobanche treated group further confirms the anti-oxidative potential of
Orobanche in renal tissue against EG-induced oxidative damage. These results support the protective effect of
Orobanche against oxidative damage suggesting, that the protective effect attributed to flavonoids and phenolic compounds. Flavonoids compounds can scavenge the free radicals and attenuate lipid peroxide. It reactivates the antioxidant defense system resulting in increasing the capacity of detoxification
(Ahmed et al., 2013).
