CP is a chemotherapeutic drug with widespread use in the treatment of solid tumors (Rixe, 2000; Goldwasser and Misset, 2001) .These include malignancies of breast, ovary (Hoskins et al., 2000, Grabosch et al., 2019), testis (de Vries et al., 2020), bladder (Taber et al., 2020), cervical (Yi et al., 2020)) and lung (Nguyen et al., 2020).
The use of this drug has been limited due to its adverse effects on different organs. Previous studies confirmed that CP has severe deleterious side effects on pregnant mothers and their fetuses (Serkies et al., 2011;Ghaseminezhad and Hejazi, 2015). On the other side, several researches emphasized that carrot flavor like garlic and several other flavors are transmitted from the nursing mother’s diet to her milk (Mennella and Beauchamp, 1999). Accordingly, the current work was mainly designed to evaluate the protective effect of garlic extract against CP-iduced nephrotoxicity in pregnant mother rats and their offsprings.
The obtained results of the current study revealed a remarkable significant decrease in the final body weight of CP-treated mother rats and their offsprings if compared with control. This result came in accordance with findings of previous studies (Abdelmaguid et al., 2010; Nasr, 2013) who recordeda significant reduction in the body weight of CP-treated rats after 3–5 days post single I.P injection of 5–7.5 mg/kg of CP. The reduction of the body weight in CP-treated rats might be in part attributed to the direct toxic effect of CP on renal tubules that caused reduction in water reabsorption and excessive sodium excretion with subsequent polyuria, dehydration and reduction of body weight (Yao et al., 2007; Azu et al., 2010). Another study postulated that the reduction in body weight in CP treated rats might be due to gastrointestinal toxicity with subsequent decrease in appetite, ingestion and assimilation of food (Arhoghro et al., 2012). The reduction in body weight of offspring which their mothers received CP may be attributed to excretion of CP metabolites in milk during breast feeding. On the other side, an obvious gain in the body weight was noticed in post-treatment of CP treated -mother rats with garlic extract. Nasr and Saleh (2014) reported that garlic extract can maintain the body weight through regulation of renal and intestinal enzyme functions. Other studies revealed that, infants whose mothers consumed carrot during pregnancy and breastfeeding periods accepted carrot-flavored cereals more readily than infants who were exposed to this flavor for the first time (Mennella et al., 2001). Further study assumed that, ingestion of garlic by pregnant women leads to longer breast attachment for their infants (Mennella et al., 1991). In contrast to obtained result concerning body weight, Dixit and Joshi (1982) was recorded a significant decrease in body weight after treatment with a garlic powder preparation by daily gavage. Such conflicting results may be attributed to the difference in exposed dose of garlic as well as the conditions of experiment.
In the current work, deleterious histological changes were recorded in the renal cortex of CP-treated mother rats and their offsprings. Such changes included atrophied glomeruli, dilatation of Bowman’s space, degeneration, necrosis and detachment of the proximal tubular epithelial cell lining, dilated tubular lumina of both proximal and distal tubules. This could be due to the cytotoxic effect of CP. Similar observations were recorded in rats exposed to different doses of CP (Mansour et al., 2006; Lawal and Ellis, 2011). Aydogan et al. (2008) postulated that CP has a direct toxic effect on the glomerular and tubularstructures through the generation of reactive oxygen species (ROS) that induces necrosis in renal tubular cells. The nephrotoxicity induced by CP in childhood cancer therapy has been demonstrated for some time, while new aspects of the tubular damage, including increased elimination of low molecular weight peptides and reduced excretion of some glycoprotein protein (Zimmerhackl, 1994). Early data on CP-induced nephrotoxicity indicated that 25% of patients have an elevation in blood nitrogen levels following 1 or 2 weeks of treatment which is considered as a main cause for glomerular and tubular damage (Kovach et al., 1974). Pinta and Lippard (1985) suggested that, the accumulation of toxic platinum metabolites of CP inside renal tubule cells seems to be one of the most important factors implicated in induction of nephrotoxicity. Other study concluded that frequent doses of CP can directly injure the renal tubules, renal vasculature, and glomeruli through induction of oxidative stress, inflammation and apoptosis (Alhoshani et al., 2017)
In the present study, a remarkable improvement was recorded in the renal tissues of mother rats administrated with garlic after treatment with CP. Several studies have demonstrated that garlic extract prevents the oxidative stress and exerts a protective effect against different toxic agents through its powerful antioxidant and free radical scavengers (Anusuya et al., 2013; Capasso, 2013). Other studies revealed thatgarlic has a powerful cytoprotective effects to the cells of vital body organs (Assayed et al., 2008; Hammami et al., 2009).
Serum creatinine and urea levels areconsidered the main biomarkers that efficiently determine the glomerularfiltration rate (Azu et al., 2010). In the present study, nephrotoxicityof CP was evident from the elevated levels of serumurea and creatinine in mother rats and their offsprings. Similar observations were previously delivered in several studies (Yao et al., 2007; Arhoghro et al., 2012). Motegi et al. (2007) reported that, use of CP by pregnant women can exhibit a reversible elevation of serum creatinine and urea of her neonates. The elevationin the serum levels of these renal biomarkers might beattributed to the impaired renal functions (Anusuya et al., 2013), tubular obstruction and cytotoxicity of the renal tubules cells (Azu et al., 2010).Several studies postulated that the disturbance in renal functions by CP is mainly due to its ability to inhibit protein synthesis in thetubular cells (Adejuwon et al., 2014) or to initiate lipid peroxidation and generatefree radicals in renal tubules (Razo-Rodríguez et al., 2008; Saad et al., 2009). Aydogan et al. (2008) added that the elevation in the renal biomarkers was due to the direct cytotoxic effect of CP on the glomerular and tubular structures through the generation of ROS.
In the present study, administration of CP followed by garlic extract revealed obvious recovery in the levels of serum creatinine and urea that markedly elevated by treatment of CP alone. This could be attributed to a cytoprotective effect of garlic. Our findings confirm those of other studies (Anusuya et al., 2013; Nasr and Saleh, 2014). Razo-Rodriguez et al. (2008) assured that garlic extract can maintain the levels of serum urea and creatinine through its organo-sulfur compounds. Moreover, these compounds could enhance the antioxidant effect and inhibit lipid peroxide levels by scavenging the free radicals and increasing intracellular concentration of glutathione.
The present study revealed a significant decrease in the serum sodium and potassium in CP-treated mother rats and their offspring. Such results came in agreement with the findings of previous studies (Xin et al., 2007; Tamim et al., 2010; Arunkumar et al., 2012) which showed excess elimination of potassium and sodium in patients treated with CP. An early study by Daugaard et al. (1988) confirmed that; CP metabolites can inhibit the mechanism involving in electrolytes reabsorption especially in the distal segment of the nephron, resulting in hypokalemia and hyponatremia. Furthermore, CP can induce disturbance in both intestinal absorption and renal tubular reabsorption of potassium (Tamim et al., 2010). Another study clarified that CPcan inhibit the activity of antidiurtic hormone (ADH) leading to hypernatremia (Surinder et al., 2010).
Garlic was known to have various active antioxidant organo-sulfur compounds mainly S-Allylcysteine and allicin (Bongiorno et al., 2008; Colin-Gonzalez et al., 2012).These compounds can enhance the cellular antioxidant enzymes, increased GPx content in the cells and scavenged the free radicals (Colin-Gonzalez et al., 2012; Capasso, 2013). The ameliorative effects of garlic against doxorubicin induced cardiotoxicity (Alkreathy et al., 2010), cadmium-induced toxicity (Lawal and Ellis, 2011) and acrylamide-induced oxidative stress in various organs (Abd El-Halim and Mohamed, 2012) have been previously documented in researches. In the current study, treatment of mother rats with garlic extract alone or in combination with CP produced significant decline in MDA level and significant increase of SOD, CAT and GPx activities in the renal tissues. These findings support the antioxidant effects of garlic extract against CP-induced oxidative damage and lipid peroxidation. Lanzotti (2006) revealed that the thiosulfinates compounds of garlic play a major role in enhancing the antioxidants enzymes. Capasso (2013) added that the protective effect of garlic is mainly mediated by its highly bioavailable and significant antioxidant compounds especially S-allyl cysteine, S-allyl mercaptocyteine, allicin, and selenium that exhibited potent antioxidant activity. Moreover, the water-soluble S-allyl cysteine reduced the extent of lipid peroxidation and obviously stimulated antioxidant activities in vitro and in vivo (Almaca, 2004). In agreement with present study, significant increase in CAT, SOD and GPx activities accompanied with significant decline in MDA was recorded in animals treated with garlic (Gorinstein et al., 2006; Adaramoye et al., 2008). The obtained results in the present work concerning the reduction in the activity of renal antioxidant enzymes; CAT, SOD and GPx and elevated lipid peroxidation (MDA) in CP treated mother rats are in accordance with the findings of previous studies (Ajith et al., 2007; Razo-Rodríguez et al., 2008). Sheikh-Hamad et al. (2004) declared that CP can liberate NO that implicated in oxidative stress and nephrotoxicity. Kart et al. (2010) added that CP is implicated in in generation of ROS that induce disturbance in membrane permeability and severe cell damage. Elevation of the MDA enhanced lipid peroxidation and increased ROS generation leading to disturbance of membrane function and integrity (Estuo, 2009). Furthermore, inhibition of antioxidant CAT, SOD, and GPx enzymes was implicated in the pathogenesis of CP-induced nephrotoxicity.
Caspases are a family of proteases that play an important role in the regulation of apoptosis (Kaushal et al., 2001). In the current investigation, caspase-3 (strong apoptotic marker) has been shown to be increased in the renal tissues of CP-treated mother's rats and their offsprings. The obtained result is in accordance with the previous studies (Kaushal et al., 2001; Park et al., 2002). Sheikh-Hamad et al. (2004) reported that, CP can induce apoptosis through activation of tumor necrosis factor (TNF) or messages form caspases 1, 2, 3 and 8 that activate caspase-3 in kidney. (Razzaque et al. (1999) revealed that CP increased expression of both Fas and Fas ligand in human proximal tubular epithelial cells which accelearate tha activity of caspse-3. Other researchers reported that, CP can induce apoptosis in the renal tubular epithelial cell lines resulting in activation of caspase-9, which is a good promoter for the mitochondrial apoptotic pathway (Blatt and Glick, 2001; Park et al., 2002). Further studies explained that CP can induce apoptosis with progressive accumulation of DNA and inhibition of DNA repair pathways, through generation of reactive oxygen species (Avan et al., 2015; Alhoshani et al., 2017).
Garlic was found to attenuate the increased caspase-3 levels induced by CP treatment. Previously, it was reported that, protein s-allyl cysteine (SAC) is the most abundant compound in the garlic extract that prevents the lipid peroxidation (LPO) by ROS, the oxidative damage to DNA and apoptosis (Mikaili et al., 2013; Nasr and Saleh, 2014).