Red Palm Oil Attenuates Lead Acetate Induced Testicular Damage in Adult Male Sprague-Dawley Rats

Ginkgo biloba supplement abates lead-induced endothelial and testicular dysfunction in Wistar rats via up-regulation of Bcl-2 protein expression, pituitary-testicular hormones and down-regulation of oxido-inflammatory reactions

BACKGROUND

Apoptotic and oxido-inflammatory pathways have been found to be up-regulated in lead acetate poisoning which has been associated to endothelial and testicular dysfunctions. It is yet uncertain, nevertheless, if treatment with Ginkgo biloba supplements (GBS), a flavonoid-rich natural product can lessen the adverse effects of lead on endothelial and testicular functions. This study investigated the impact of Ginkgo biloba supplementation on lead-induced endothelial and testicular dysfunctions.

METHODS

The animals were treated with GBS (50 mg/kg and 100 mg/kg orally) for 14 days following oral exposure to lead acetate (25 mg/kg) for 14 days. After euthanasia, blood samples, epididymal sperm, testes, and aorta were collected. The quantities of the hormones (testosterone, follicle stimulating hormone (FSH) and luteinizing hormone (LH), as well as the anti-apoptotic, oxidative, nitrergic, inflammatory markers, were then determined using immunohistochemistry, ELISA, and conventional biochemical methods.

RESULTS

GBS reduced lead-induced oxidative stress by increasing the levels of the antioxidant enzymes catalase (CAT), glutathione (GSH), and superoxide dismutase (SOD), while lowering malondialdehyde (MDA) in endothelium and testicular cells. Normal testicular weight was restored by GBS which also decreased endothelial endothelin-I and increased nitrite levels. TNF-α and IL-6 were decreased while Bcl-2 protein expression was enhanced. Lead-induced alterations in reproductive hormones (FSH, LH, and testosterone) were also restored to normal.

CONCLUSION

According to our result, using Ginkgo biloba supplement prevented lead from causing endothelial and testicular dysfunction by raising pituitary-testicular hormone levels, boosting Bcl-2 protein expression and lowering oxidative and inflammatory stress in the endothelium and testes.

Protective effects of Asparagus officinalis (asparagus) against lead toxicity in mice

One of the most prevalent harmful heavy metals is lead (Pb). It is generally recognized to be harmful to the testicles. Asparagus officinalis has many saponins, flavonoids, and other phenolics with strong antioxidant and anti-inflammatory effects. The effects of A. officinalis (asparagus) aqueous extract (AOAE) on testicular damage caused by lead acetate (PbAc) were investigated in this study. In this way, 20 mg/kg PbAc was injected intraperitoneally 2 h after mice were administered 400 mg/kg AOAE orally for 14 days. In the biochemical analysis of testicular tissue, PbAc decreased enzymatic and nonenzymatic antioxidant molecules in testicular tissue, while increasing lipid peroxidation, nitric oxide, inflammatory markers [nuclear factor kappa-B (NF-κB), tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1 β), IL-6, and inducible nitric oxide synthase (iNOS)], and apoptotic-related proteins. Additionally, PbAc was discovered to reduce sperm motility and increase the percentage of dead sperm. However, due to its antioxidant qualities, AOAE has been found to reduce oxidative stress, therefore protecting against inflammation and apoptosis. It also allowed the AOAE sperm parameters to restore to their previous values in the control group. According to the findings, AOAE could be a natural substance that could be used to treat Pb-induced testicular toxicity; this protection may be attributed to its anti-oxidative, anti-inflammatory, and anti-apoptotic effects. However, this study warrants further works to explore in detail the underlying mechanisms of the alleviating effects of AOAE against Pb-induced toxicity and which of its active ingredients is responsible for this protection.

Glycine Betaine Relieves Lead-Induced Hepatic and Renal Toxicity in Albino Rats

Lead (Pb) is a widespread and nondegradable environmental pollutant and affects several organs through oxidative mechanisms. This study was conducted to investigate the antioxidant protective effect of glycine betaine (GB) against Pb-induced renal and hepatic injury. Male albino rats (n = 45) were divided into three groups: G1 untreated control, G2 Pb-acetate (50 mg/kg/day), and G3 Pb-acetate (50 mg/kg/day) plus GB (250 mg/kg/day) administered for 6 weeks. For G3, Pb-acetate was administered first and followed by GB at least 4 h after. Pb-acetate treatment (G2) resulted in a significant decrease in renal function, including elevated creatinine and urea levels by 17.4% and 23.7%, respectively, and nonsignificant changes in serum uric acid levels. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphates (ALP) activities were significantly increased with Pb treatment by 37.6%, 59.3%, and 55.1%, respectively. Lipid peroxidation level was significantly increased by 7.8 times after 6 weeks of Pb-acetate treatment. The level of reduced glutathione (GSH-R) significantly declined after Pb-acetate treatment. Pb-acetate treatment also reduced the activities of superoxide dismutase (SOD), glutathione-S-transferase (GST), and glutathione peroxidase (GSH-PX) by 74.1%, 85.0%, and 40.8%, respectively. Treatment of Pb-intoxicated rats with GB resulted in a significant reduction in creatinine, urea, ALT, AST, and lipid peroxidation, as well as a significant increase in the level of GSH-R and in the activities of ALP, SOD, GST, and GSH-PX. The molecular interaction between GB and GSH-PX indicated that the activation of GSH-PX in Pb-intoxicated rats was not the result of GB binding to the catalytic site of GSH-PX. The affinity of GB to bind to the catalytic site of GSH-PX is lower than that of H₂O₂. Thus, GB significantly mitigates Pb-induced renal and liver injury through the activation of antioxidant enzymes and the prevention of Pb-induced oxidative damage in the kidney and liver.

Cabbage (Brassica oleracea) mitigates lead (II) acetate-induced testicular dysfunction in Wistar rats via up-regulation of Bcl-2 protein expression, pituitary-testicular hormonal axis and down-regulation of oxido-inflammatory reactions

Oxido-inflammatory stress has been involved in lead-induced testicular dysfunction and plants rich in anti-oxidants has been reported to be beneficial in combating heavy metal poisonings in animal studies. However, cabbage juice protective effect on lead-induced testicular dysfunction was investigated in this study. Twenty male Wistar rats were selected into four (n = 5) groups and given distilled water (1 ml/100 g body weight), lead acetate (25 mg/kg body weight), cabbage juice (1 ml/100 g body weight), and lead acetate with cabbage juice, respectively. All treatments were administered orally for 28 days. Sperm count, motility, viability, testosterone, luteinising hormone and follicle-stimulating hormone, testicular Bcl-2 expression, and enzymatic anti-oxidant capabilities were considerably (p < 0.05) decrease in lead-treated animals. However, cabbage juice significantly (p < 0.05) elevated these parameters. Testicular malondialdehyde, tumour necrosis factor-α, nitric oxide and interleukin-6 was elevated by lead acetate. When comparing cabbage juice-treated animals to lead-treated animals, all of these parameters were considerably (p < 0.05) downregulated in cabbage juice-treated animals. Following lead administration, the testes' histomorphological alterations were not totally recovered despite therapy with cabbage juice. Conclusively, this study suggest that cabbage juice mitigates testicular dysfunction associated with lead exposure via its anti-oxidant, anti-inflammatory, anti-apoptotic and androgenic properties.

Aqueous extract of Pedalium murex D. Royen ex L. leafy stem protects against lead induced testicular toxicity in Wistar rats

OBJECTIVES

Lead exposure seriously impairs male reproductive function. The protective capacity of Pedalium murex leafy stem and fruit aqueous extracts against lead testicular toxicity is evaluated to find herbals drugs able to improve semen quality.

METHODS

Phytochemical screening were performed according to classical methods. Twenty four male rats were divided into four groups of six rats each and received the following treatments via oral route: distilled water; 0.2% lead acetate in drinking water; 0.2% lead acetate in drinking water with 400 mg/kg P. murex aqueous leafy stem extract; 0.2% leaded water with 400 mg/kg P. murex aqueous fruit extract. Treatments were administered for 70 days. Body and reproductive organs weights, sperm parameters and testicular histological sections of each group were examined.

RESULTS

Flavonoids, tannins, coumarins, alkaloids, and lignans were found in both extracts. Lead intoxication reduced sperm motility and count but increased the percentage of morphologically abnormal sperms. The germinal epithelium of seminiferous tubules histoarchitecture was disorganized by lead. The leafy stem extract was effective in reducing lead induced testicular disruption whereas fruit has not shown any beneficial effect.

CONCLUSIONS

P. murex leafy stem aqueous extract is effective against semen alterations caused by lead.

Impact of Malaysian palm oil on sustainable development goals: co-benefits and trade-offs across mitigation strategies

Palm oil (PO) is an important source of livelihood, but unsustainable practices and widespread consumption may threaten human and planetary health. We reviewed 234 articles and summarized evidence on the impact of PO on health, social and economic aspects, environment, and biodiversity in the Malaysian context, and discuss mitigation strategies based on the sustainable development goals (SDGs). The evidence on health impact of PO is equivocal, with knowledge gaps on whether moderate consumption elevates risk for chronic diseases, but the benefits of phytonutrients (SDG2) and sensory characteristics of PO seem offset by its high proportion of saturated fat (SDG3). While PO contributes to economic growth (SDG9, 12), poverty alleviation (SDG1, 8, 10), enhanced food security (SDG2), alternative energy (SDG9), and long-term employment opportunities (SDG1), human rights issues and inequities attributed to PO production persist (SDG8). Environmental impacts arise through large-scale expansion of monoculture plantations associated with increased greenhouse gas emissions (SDG13), especially from converted carbon-rich peat lands, which can cause forest fires and annual trans-boundary haze; changes in microclimate properties and soil nutrient content (SDG6, 13); increased sedimentation and change of hydrological properties of streams near slopes (SDG6); and increased human wildlife conflicts, increase of invasive species occurrence, and reduced biodiversity (SDG14, 15). Practices such as biological pest control, circular waste management, multi-cropping and certification may mitigate negative impacts on environmental SDGs, without hampering progress of socioeconomic SDGs. While strategies focusing on improving practices within and surrounding plantations offer co-benefits for socioeconomic, environment and biodiversity-related SDGs, several challenges in achieving scalable solutions must be addressed to ensure holistic sustainability of PO in Malaysia for various stakeholders.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11625-021-01052-4.

Repeatedly heated palm olein disrupts male reproductive system of rat: A histological and biochemical study

The aim of this study was to investigate the effect of heated and unheated palm olein in different doses on the male reproductive system of rats. Forty male rats were randomly classified into five groups (n = 8) including Control, Low palm, High palm, Heated low palm and Heated high palm. The palm olein was administrated orally for 6 months. Histological and biochemical parameters of the male reproductive system were measured. There was a significant reduction in sexual hormones, serum levels of superoxide dismutase, high-density lipoprotein, testis weight and sperm parameters in the high dose and heated palm olein groups compared to the other group (p < 0.05). The levels of malondialdehyde, apoptosis rate, proteins levels (TNF-α, IL-1β, IL-6), low-density lipoprotein, cholesterol, triglyceride and the weight of the rats were significantly higher in the high dose and heated palm olein groups than the others (p < 0.05). High dose and heated palm olein treatment could damage the male rat's reproductive indices that were related to increased inflammatory markers, decreased sex hormone levels, and negative effects on testicular tissue and sperm parameters.

Chlorella vulgaris or Spirulina platensis mitigate lead acetate-induced testicular oxidative stress and apoptosis with regard to androgen receptor expression in rats

The current research was constructed to throw the light on the protective possibility of Chlorella vulgaris (C. vulgaris) and Spirulina platensis (S. platensis) against lead acetate-promoted testicular dysfunction in male rats. Forty rats were classified into four groups: (i) control, (ii) rats received lead acetate (30 mg/kg bw), (iii) rats concomitantly received lead acetate and C. vulgaris (300 mg/kg bw), (vi) rats were simultaneously treated with lead acetate and S. platensis (300 mg/kg bw) via oral gavage for 8 weeks. Lead acetate promoted testicular injury as expressed with fall in reproductive organ weights and gonadosomatic index (GSI). Lead acetate disrupted spermatogenesis as indicated by sperm cell count reduction and increased sperm malformation percentage. Lead acetate-deteriorated steroidogenesis is evoked by minimized serum testosterone along with maximized follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels. Testicular oxidative, inflammatory, and apoptotic cascades are revealed by elevated acid phosphatase (ACP) and sorbitol dehydrogenase (SDH) serum leakage, declined testicular total antioxidative capacity (TAC) with elevated total oxidative capacity (TOC), tumor necrosis factor alpha (TNF-α), caspase-3 levels, lessened androgen receptor (AR) expression, and histopathological lesions against control. Our research highlights that C. vulgaris or S. platensis therapy can modulate lead acetate-promoted testicular dysfunction via their antioxidant activity as expressed by elevated TAC and reduced TOC, immunomodulatory effect as indicated by lessened TNF-α level, and anti-apoptotic potential that was revealed by minimized caspase-3 levels. As well as restoration of testicular histoarchitecture, androgen receptor, steroidogenesis, and spermatogenesis were detected with better impacts to S. platensis comparing with C. vulgaris. Therefore, further clinical trials are needed to test S. platensis and C. vulgaris as a promising candidate in treating male infertility.

Ameliorative effect of L-carnitine on chronic lead-induced reproductive toxicity in male rats

Lead toxicity is one of the causative agents of male infertility that raised concern from environmental contamination worldwide. L‐carnitine, a biologically active amino acid, present in high concentration in the reproductive organs such as the epididymis, is involved in sperm maturation. The possible protective effect of L‐carnitine in experimentally lead‐induced male reproductive toxicity in rats was evaluated in this study. Thirty adult male Wistar rats were divided into three groups. Group 1: the negative control group was treated with normal saline; Group 2: exposed to 50 mg/kg lead acetate (2% solution in saline); and Group 3: treated with lead acetate 50 mg/kg (2% solution in saline) + L‐carnitine 100 mg/kg. At the end of the experimental period, body and testicular weights were determined, blood samples were withdrawn for hormonal assays of FSH, LH and testosterone. Sperm parameters as sperm count, morphology, viability and motility were measured. Testicular tissue homogenates were prepared for enzymatic assays and for measuring oxidative stress parameters. Lead significantly increased both oxidative stress and the concentration of lactate dehydrogenase‐C in the testicular tissues with a decrease in sperm count, motility and viability. Lead acetate treatment, induced alteration in sperms with normal morphology together with reductions in the serum FSH, LH, testosterone, body and testicular weights. The concentration of 17β‐hydroxysteroid dehydrogenase was significantly reduced. Co‐administration of L‐carnitine significantly reduced testicular oxidative stress, improved sperm parameters, elevated serum FSH, LH and testosterone with an insignificant reduction in the testicular weight. The concentrations of 17β‐hydroxysteroid dehydrogenase and lactate dehydrogenase‐C were significantly improved by L‐carnitine. The overall results indicate that L‐carnitine is expected to improve the lead acetate‐induced male reproductive toxicity.

A potential mechanism associated with lead-induced spermatogonia and Leydig cell toxicity and mitigative effect of selenium in chicken

Lead (Pb) is a toxic heavy metal pollutants and can damage male reproductive function. Selenium (Se) possesses an ability of antagonizing Pb toxicity. However, biological events in the process of Pb toxicity and mitigative effect of Se are not well understood. The aim of present research was to investigate potential mechanism of Se against Pb toxicity from the perspective of oxidative stress, heat shock response and autophagy in the spermatogonia and Leydig cell of chicken. The cells from one-day-old male Hyline chickens were treated with Se (0.5 μmol/L) and/or Pb (20 μmol/L) for 24 h, respectively. Cell viability, cell ultrastucture, Pb and Se concentrations, testosterone level, oxidative stress indicators and relative expression of heat shock proteins (HSPs) and autophagy-related genes were measured. The results showed that spermatogonia was more tolerant to Pb than Leydig cell; cell injury was confirmed via histological assessment, cell viability and testosterone level; oxidative stress was further indicated by the decrease of catalase, glutathione peroxidase, glutathione-s-transferase and superoxide dismutase activities and the increase of malondialdehyde and reactive oxygen species contents. Pb increased expression of HSPs (27, 40, 60, 70 and 90). Meanwhile Pb induced autophagy through up-regulation of autophagy-related proteins 5, Beclin 1, Dynein, light chain 3 (LC3)-I and LC3-II and down-regulation of mammalian target of rapamycin in two type cells of chicken. However, Se intervention mitigated the aforementioned alterations caused by Pb. In conclusion, Pb led to oxidative stress, which triggered heat shock response and autophagy; Se administration mitigated reproductive toxicity of Pb through strengthening antioxidant defense in the spermatogonia and Leydig cell of chicken.

Antioxidant, anti-inflammatory and anti-apoptotic effects of hydro-ethanolic extract of Cyperus esculentus L. (tigernut) on lead acetate-induced testicular dysfunction in Wistar rats

AIM

Lead acetate impairs testicular function by enhancing testicular oxidative stress and apoptosis. Cyperus esculentus possesses antioxidants and has shown great improvement of testicular function. This study investigated the protective effect of hydro-ethanolic extract of Cyperus esculentus on lead acetate-induced testicular dysfunction in Wistar rats.

MATERIALS AND METHODS

Twenty-five male Wistar rats (180-195 g) were randomly divided into 5 groups (n = 5) namely: Normal control (NC), Lead control (PbC) (20 mg/kg b.w. i.p.), C. esculentus-treated (CE) (500 mg/kg b.w p.o.), Pb + CE(500) (20 mg/kg of lead and 500 mg/kg of extract) and Pb + CE(1000) (20 mg/kg of lead and 1000 mg/kg of extract). Administration lasted for 21 days.

RESULTS

Sperm count, motility, viability, serum testosterone and follicle stimulating hormone, Johnsen's score, Leydig cell count, Sertoli cell count, testicular testosterone, B-cell lymphoma protein-2 (Bcl-2), steroidogenic acute regulatory protein, cytochrome P450 A1, 3β-hydroxysteroid dehydrogenase (HSD), 17β-HSD, enzymatic antioxidant activities and total antioxidant capacity were significantly (p < 0.05) decreased in PbC compared with NC. These parameters however increased significantly (p < 0.05) in Pb + CE(500) and Pb + CE(1000) compared with PbC. Lead acetate upregulated (p < 0.05) testicular malondialdehyde, nitric oxide, glucose, lactate, lactate dehydrogenase, C-reactive protein, tumor necrosis factor-α, interleukin (IL)-6, IL-1β, Bcl-2 associated X (Bax), Bax/Bcl-2 and cleaved caspase-3 levels. All these parameters were downregulated (p < 0.05) in Pb + CE(500) and Pb + CE(1000) in comparison with PbC.

CONCLUSION

C. esculentus exhibited a dose-dependent mitigation of lead acetate-induced testicular dysfunction in Wistar rats via its antioxidant, anti-inflammatory and anti-apoptotic effects.

Vitamin D alleviates lead induced renal and testicular injuries by immunomodulatory and antioxidant mechanisms in rats

This study measured the effects of vitamin D (VD) supplementation on the underlying molecular pathways involved in renal and testicular damage induced by lead (Pb) toxicity. Thirty two adult male Wistar rats were divided equally into four groups that were treated individually or simultaneously, except the negative control, for four weeks with lead acetate in drinking water (1,000 mg/L) and/or intramuscular VD (1,000 IU/kg; 3 days/week). Pb toxicity markedly reduced serum VD and Ca²⁺, induced substantial renal and testicular injuries with concomitant significant alterations in the expression of VD metabolising enzymes, its receptor and binding protein, and the calcium sensing receptor. Pb also significantly promoted lipid peroxidation and pro-inflammatory cytokines (IL-4 and TNF-α) in the organs of interest concomitantly with declines in several anti-oxidative markers (glutathione, glutathione peroxidase and catalase) and the anti-inflammatory cytokine, IL-10. The co-administration of VD with Pb markedly mitigated renal and testicular injuries compared with positive controls. This was associated with restoration of the expression of VD related molecules, promotion of anti-oxidative and anti-inflammatory markers, but tissue Pb concentrations were unaffected. In conclusion, this report is the first to reveal potential protective effects for VD against Pb-induced renal and testicular injuries via anti-inflammatory and anti-oxidative mechanisms.

Lead Inhibits Human Sperm Functions by Reducing the Levels of Intracellular Calcium, cAMP, and Tyrosine Phosphorylation

It is well known that there has been a worldwide decrease in human male fertility in recent years. One of the main factors affecting this is environmental pollution. Lead is one of the major heavy metal contaminants that threaten the health of animals and human beings in China. It preferentially accumulates in male reproductive organs and can be up to 10 µM in human seminal plasma. Lead impairs mammalian spermatogenesis and sperm quality in vivo. It also inhibits sperm functions in vitro but the underlying mechanisms remain unclear. Therefore, we aimed to investigate the in vitro toxicity of lead on human sperm functions and to elucidate the underlying mechanisms. Semen samples were collected from 20 healthy volunteers with different careers and backgrounds living in Nanchang, Jiangxi. Human sperm suspensions were treated with different concentrations of lead acetate (0, 0.5, 2.5, 10, 50, and 100 µM) and the viability, motility, capacitation and progesterone-induced acrosome reaction were examined. Treatment with 10-100 µM lead acetate dose-dependently inhibited total and progressive motility measures, capacitation and progesterone-induced acrosome reaction. It also dose-dependently decreased the intracellular concentrations of cyclic adenosine monophosphate (cAMP) and calcium ([Ca(2+)]i), and reduced the tyrosine phosphorylation of sperm proteins, all of which are thought to be key factors in the regulation of sperm function. Our findings suggest that lead inhibits human sperm functions by reducing the levels of sperm intracellular cAMP, [Ca(2+)]i and tyrosine phosphorylation of sperm proteins in vitro.

Ferulic acid prevents lead-induced testicular oxidative stress and suppressed spermatogenesis in rats

Lead affects multiple organ systems including testis. We investigated the effects of ferulic acid (FA) on lead-induced oxidative stress and spermatogenesis suppression in rats. Animals received lead acetate (500 mg/L in drinking water) and/or FA (50 mg/kg, i.g.) for eight weeks. Lead increased testicular malondialdehyde (MDA) and nitrite levels and decreased glutathione (GSH) content and catalase (CAT) activity. Lead decreased testis weight and testosterone level. Sperm parameters decreased in lead group. FA ameliorated the decreased testis weight, serum testosterone as well as sperm count, viability, motility and normal morphology in lead group. FA improved antioxidant capacity as well as sperm count, viability, motility and normal morphology. FA decreased Johnsen's mean testicular biopsy score (MTBS) criteria by restoring degeneration, atrophy and tubular disarrangement. FA also normalised spermatogonia, spermatocytes and spermatids numbers in lead group and led to increases in number of Leydig and Sertoli cells. FA showed beneficial effects in lead-induced testicular oxidative stress and spermatological disorders, through inhibiting lipid peroxidation and enhancing antioxidant defence systems. The positive effects of FA on Leydig cells may be involved in restoring testosterone levels in lead group. FA can be considered a potential candidate to protect testis against the deleterious effect of lead intoxication.