Lead is one of male reproductive toxicant in humans and animals elicits testicular dysfunction and infertility (Al-Megrin et al. 2020).
In the running study, lead acetate prompted reduction in body weight gain comparing to control that may contribute to imbalance metabolism due to impairing zinc level whereby required for metabolic processes (Ademuyiwa et al. 2010). Or lead acetate may decrease feed intake (Winiarska-Mieczan et al. 2018).
Additionally, fall in reproductive organ weights, GSI, sperm cell count, and elevation in sperm malformation percentage were recorded in lead acetate treated rats. Our findings came in harmony with (Vidal and Whitney 2014) who demonstrated that testicular weight is correlated with the differentiated spermatogenic cells mass. Thereby, lessened GSI implying loss of germ cell. Importantly, lead accumulation in reproductive organs generated ROS altering steroidogenesis and spermatogenesis (Jegede et al. 2015). Also, lead lessened sperm calcium and cyclic adenosine monophosphate levels lowering tyrosine phosphorylation of protein and hindering sperm impairment (He et al. 2016). We herein explored that lead acetate significantly elevated ACP and SDH activity in sera versus control. ACP is secreted by Sertoli cells and detected in lysosomes of Leydig cells mediated lysis of abnormal sperms (Olayinka and Ore 2015). While, SDH is distributed in spermatogenic cells of seminiferous tubules and correlated with germ cell maturation via energy supply by conversion of sorbitol to fructose (Tripathi et al. 2016). Remarkably, Lead acetate has been evidenced in testicular accumulation with subsequent upregulation of reactive oxygen species (ROS) generation along with antioxidants downregulation promoting cellular membrane harm via lipid peroxidation (El-Khadragy et al. 2020). ROS- induced cellular injury and could be associated with enzyme liberation into the circulation (Hassan et al. 2013). Hence, elevated serum ACP and SDH implying testicular oxidative burden promoted by lead acetate.
Concerning hormonal profile, lead acetate disrupted steroidogenesis confirmed by minimized serum testosterone levels along with maximized FSH, LH levels, and downregulation in nuclear AR expression in spermatogenic cells and Leydig cells versus control. Fall in testosterone level can attribute to lead- promoted testicular oxidative and immune response consistently with (Allouche et al. 2009; Udefa et al. 2020). These are similarly to our findings reveal decline in testicular TAC with elevation in TOC, and TNF-α levels. These may account to Lead acetate counteracted antioxidant enzymes activities through targeting SH groups and/ or metal cofactors of antioxidants (Patra et al. 2011). As well as, lead acetate downregulated Nfe212 gene expression- promoted downregulation of antioxidant enzymes expression (Kabel and Elkhoely 2017).The resulted testicular oxidative response is proposed as prospective pathway for immune response via TNF-α expression by macrophages post lead acetate exposure (Salama et al. 2016). These resulting in steroidogenesis inhibition in Leydig cells whereby TNF-α lessened testicular 3b- and 17b-17ß-hydroxysteroid dehydrogenase activity resulting in reduced testosterone level (Hales 2002; Hong et al. 2004). Consequently, AR damage are occurred in response to testicular oxidative burden (Chang et al. 2019; Yao et al. 2007).
Next, AR possessed a fundamental role in testosterone feedback regulation via autocrine action on Leydig cells, through decreasing Gonadotropin-releasing hormone (GnRH) resulted in pituitary LH inhibition (Amory and Bremner 2001). Further, downregulation of AR expression in high fat diet supplemented mice was associated with minimization in testosterone level and infertility (Fan et al. 2015).Therefore, regressed AR expression may be raised LH and FSH release to compensate the testicular disruptions and testosterone depletion.
Furthermore, TNF-α- mediated disruption of mitochondrial membrane that accompanied by cytochrome C release, caspase-9, and Caspase-3 activation mediated apoptosis (Zhou et al. 2019). Moreover, Lead acetate in spermatogenic cells upregulated caspase-3, and Bax in line with downregulated Bcl2 (Hassan et al. 2019). Consequently, further germ cells apoptosis, sperm membrane perturbation and DNA fragmentation are detected (Henkel et al. 2010). Currently, these findings were confirmed by the testicular architectural deteriorations that revealed irregular shape of seminiferous tubules with no evidence of spermatozoa formation and Leydig cell hyperplasia.
On the contrary, co-therapy of lead acetate with C. vulgaris or S. platensis significantly attenuated lead acetate promoted testicular dysfunction.
Concerning the reproductive defensive mechanism of C. vulgaris is supported by our data such restoration of weight gain, sex organ weight, serum ACP, SDH activity, testosterone, FSH, LH levels, sperm cell count, and lessened sperm malformation percentage and upregulation of testicular AR expression. AS well as, upregulation in testicular TAC, downregulation in TOC, TNF-α and Caspase-3 expression were recorded agreeing with (Abdelhamid et al. 2020; Mustafa 2015; Raj et al. 2013; Vijayavel et al. 2007). These findings emphasized many previously published researches. Feeding of C. vulgaris enriched diet 0, 3 or 5% upregulated liver and plasma antioxidant enzymes in cadmium- exposed rats for 10 weeks (Son et al. 2009). Moreover, C. vulgaris (150 mg/kg b.w) ameliorated lipid peroxidation, DNA damage, TNF-α expression, as well as restored antioxidant enzymes in STZ diabetic rats (Aizzat et al. 2010). Furthermore, C. vulgaris supplementation (50 mg/kg bw) counteracted aging- promoted oxidative stress in C57BL/6 mice for eight weeks (Aliahmat et al. 2012). Similarly, (Mustafa 2015) proposed that co-treating of C. vulgaris (50 mg/kg bw) with lead acetate 200 mg/l for 12 weeks was able to restore thickness of germinal epithelium diameter of seminiferous tubules and, and sperm structure that is due to its chelating and antioxidant potential. Recently, C. vulgaris dietary supplementation upregulated hepatic and ovarian antioxidants gene expression, as well as body performance enhancement in New Zealand White rabbits (Sikiru et al. 2019).
These curative effects may attribute to its antioxidant content such as lycopene, eicosatetraenoic, docosahexaenoic acid, astaxanthin, polysaccharides, polyphenols, lutein and fucoxanthin, omega 3, omega 6, reduced glutathione, chlorophyll, and vitamin C, E (Rahimnejad et al. 2017; Renju et al. 2014; Vijayavel et al. 2007) highlighting its direct ROS scavenging properties. Accordingly, lycopene upregulated the epididymal AR expression in Polychlorinated Biphenyls–intoxicated rats (Raj et al. 2013). Eicosapentaenoic and docosahexaenoic acid counteracted cisplatin-promoted testicular and seminal toxicity in rats (Ciftci et al. 2014). Further, astaxanthin ameliorated testicular and sex hormone alterations in high fructose supplemented rats (Dokumacioglu et al. 2018). In vitro and in vivo, C. vulgaris polysaccharides evoked antioxidant possibilities via scavenging superoxide, DPPH and hydroxyl radical-scavenging (Yu et al. 2019). Furthermore, omega-3 fatty acids pronounced antioxidant and anti-inflammatory activities in a rat model of stress-induced liver injury (Ali and Rifaai 2019).
In this context, oral S. platensis administration reserved weight gain and reproductive organ weights that may relate to direct lead adsorption by S. platensis favoring rapid body lead elimination (Banji et al. 2013). As well as, S. platensis nutritional ingredient such protein, essential fatty acids, vitamins, iron, zinc, polysaccharides, phenols, carotenoids, chlorophyll, C-Phycocyanin pigment are enriched the body (Hosseini et al. 2013).
More confirmation in our work, S. platensis alleviated serum ACP, SDH activity, testosterone, FSH, LH alterations, sperm cell count, and lessened sperm malformation percentage. Also, it upregulated testicular AR, TAC along with downregulated TOC, TNF-α, Caspase-3 expression agreeing with many previous researches (Abdel-Daim et al. 2019; Bashandy et al. 2016; Esener et al. 2017; Sadek et al. 2017). Oral pretreatment with S. platensis (500 and 1000 mg/kg bw) one hour prior to deltamethrin exposure for five days improved hepatic and renal antioxidants prospect (Abdel-Daim et al. 2013). Moreover, twice weekly oral supplementation of S. platensis (500 mg/kg b.w) for eight weeks exhibited hepatic and pancreatic β-cells antioxidant, anti-inflammatory, and anti-apoptotic potential in STZ- diabetic rats (Sadek et al. 2017). Furthermore, administration of S. platensis (300 mg/kg bw) for four weeks could alleviate sperm quality and sex hormone alterations in furan treated rats (Abd El-Hakim et al. 2018). Similarly, another strain, S. maxima was able to up reregulate testicular antioxidant enzymes and downregulate caspase-3 in lead acetate-exposed rats (Abdrabou et al. 2019).
These ameliorative events may attribute to antioxidant active ingredients of S. platensis. Phenols scavenged ROS and improved testicular antioxidant status in alloxan-diabetic rats (Roy et al. 2015). Specifically, C-phycocyanin is detected in Spirulina only and revealed antioxidant and antiapoptotic potentials in cardiomyocytes of doxorubicin- treated rats (Khan et al. 2006), and in paraquat- promoted acute lung injury in rats (Sun et al. 2011). Chlorophyll evoked counteracted sodium nitrate- induced renal and hepatic oxidative burden in rats (Suparmi et al. 2016). Moreover, vitamin C, E influenced testicular antioxidant attributes versus lead in rats (Ayinde et al. 2012).These are consolidated by architectural restoration as evident by presence of uniform Seminiferous tubules and spermatozoa.
Therefore, the antioxidant and anti-inflammatory potency of C. vulgaris and S. platensis can reverse lead acetate- fostered oxidants, TNF-α, and caspase 3 expression- mediated testicular apoptosis, AR damage and steroidogenesis inhibition in Leydig cells. Hence, testosterone and AR restoration boosted spermatogenesis are expressed by remarkably raised sperm count and sex organ weight.