Effects of sub-chronic aluminum chloride on spermatogenesis and testicular enzymatic activity in male rats

Aims

The aim of this study was to determine the effects of sub-chronic aluminum chloride (AlCl₃) on spermatogenesis and testicular enzymatic activity in male rats.

Main methods

Forty Wistar male rats were randomly divided into four groups: control group (CG, 0), low-dose group (LG, 64.18 mg/kg BW AlCl₃), mid-dose group (MG, 128.36 mg/kg BW AlCl₃) and high-dose group (HG, 256.72 mg/kg BW AlCl₃). The rats were orally administered with AlCl₃ for 120 days. At the end of the experiment, the contents of Al, Fe, Cu and Zn, the enzyme activities of testicular acid phosphatase (ACP), succinate dehydrogenase (SDH), lactate dehydrogenase (LDH), lactate dehydrogenase isoenzyme (LDH-x), the sperm count and the sperm malformation rate were examined.

Key findings

The results showed that the Al and Cu contents, sperm count and the enzyme activities of testicular ACP, SDH, LDH and LDH-x decreased, while the Zn and Fe contents and sperm malformation rate increased in AlCl₃-treated rats.

Significance

It suggests that sub-chronic AlCl₃ disorders the balance of trace element and decreases the spermatogenesis and the activities of testicular enzymes, indicating that AlCl₃ has adverse effect on the testicular function in male rats.     

Studies on the protective role of vitamin C and E against polychlorinated biphenyl (Aroclor 1254)—induced oxidative damage in Leydig cells

Free radical production and lipid peroxidation are potentially important mediators in testicular physiology and toxicology. Polychlorinated biphenyls (PCBs) are global environmental contaminants that cause disruption of the endocrine system in human and animals. The present study was conducted to elucidate the protective role of vitamin C and E against Aroclor 1254-induced changes in Leydig cell steroidogenesis and antioxidant system. Adult male rats were dosed for 30 days with daily intraperitoneal (ip) injection of 2 mg/kg Aroclor or vehicle (corn oil). One group of rats was treated with vitamin C (100 mg/kg bw/day) while the other group was treated with vitamin E (50 mg/kg bw/day) orally, simultaneously with Aroclor 1254 for 30 days. One day after the last treatment, animals were euthanized and blood was collected for the assay of serum hormones such as luteinizing hormone (LH), thyroid stimulating hormone (TSH), prolactin (PRL), triiodothyronine (T₃), thyroxine (T₄), testosterone and estradiol. Testes were quickly removed and Leydig cells were isolated in aseptic condition. Purity of Leydig cells was determined by 3β-hydroxysteroid dehydrogenase (3β-HSD) staining method. Purified Leydig cells were used for quantification of cell surface LH receptors and steroidogenic enzymes such as cytochrome P₄₅₀ side chain cleavage enzyme (P₄₅₀scc), 3β-hydroxysteroid dehydrogenase (3β-HSD) and 17β-hydroxysteroid dehydrogenase (17β- HSD). Leydig cellular enzymatic antioxidants superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), γ-glutamyl transpeptidase (γ-GT), glutathione-S-transferase (GST) and non-enzymatic antioxidants such as vitamin C and E were assayed. Lipid peroxidation (LPO) and reactive oxygen species (ROS) were also estimated in Leydig cells. Aroclor 1254 treatment significantly reduced the serum LH, TSH, PRL, T₃, T₄, testosterone and estradiol. In addition to this, Leydig cell surface LH receptors, activities of the steroidogenic enzymes such as cytochrome P₄₅₀scc, 3β-HSD, 17β-HSD, antioxidant enzymes SOD, CAT, GPX, GR, γ-GT, GST and non-enzymatic antioxidants such as vitamin C and E were significantly diminished whereas, LPO and ROS were markedly elevated. However, the simultaneous administration of vitamin C and E in Aroclor 1254 exposed rats resulted a significant restoration of all the above-mentioned parameters to the control level. These observations suggest that vitamin C and E have ameliorative role against adverse effects of PCB on Leydig cell steroidogenesis.     

Biotin,coenzyme Q10, and their combination ameliorate aluminium chloride‐induced Alzheimer's disease via attenuating neuroinflammation and improving brain insulin signaling

Insulin is important for brain function and neuronal survival. Insulin signaling is initiated by the phosphorylation of insulin receptor substrate‐1 (IRS‐1) at tyrosine (pTyr) residue. However, IRS‐1 is inhibited by phosphorylation at serine (pSer). In Alzheimer's disease (AD), oxidative stress and accumulation of amyloid beta (Aβ) induce neuroinflammation, which augments pSer‐IRS‐1 and reduces pTyr‐IRS‐1 disturbing insulin signaling pathway. Coenzyme Q10 (CoQ10) and biotin possess antioxidant and anti‐inflammatory properties, and, in this study, their impact on insulin signaling is investigated in an aluminium chloride (AlCl₃) model of AD. AD was induced by oral administration of AlCl₃ (75 mg/kg) for 60 days. Biotin (2 mg/kg), CoQ10 (10 mg/kg), and their combination were supplemented concomitantly with AlCl₃ for 60 days. Memory test and histological examination were performed. Brain levels of lipid peroxides, antioxidants (reduced glutathione and superoxide dismutase), inflammatory markers (tumor necrosis factor‐α, interleukin‐6 [IL‐6], IL‐1, and nuclear factor κB), and phosphorylated Akt (survival kinase) as well as protein levels of Aβ, IRS‐1 (pTyr and pSer), and caspase‐3 (apoptotic marker) were determined. AlCl₃ resulted in impaired memory, significant increase in Aβ, lipid peroxides, inflammatory markers, caspase‐3, and pSer‐IRS‐1, with significant reduction of the antioxidants, pTyr‐IRS‐1, and p‐Akt reflecting Aβ‐induced inflammation and defective insulin signaling. Histological examination revealed focal aggregations of inflammatory cells and neuronal degeneration. The biochemical deviations and histological changes were attenuated by the concomitant treatment with biotin and, to greater extent, with CoQ10 and the combination. In conclusion, biotin and CoQ10 could protect against AD via attenuating inflammatory response and enhancing insulin signaling.     

Bromelain from Ananas comosus stem attenuates oxidative toxicity and testicular dysfunction caused by aluminum in rats

BACKGROUNDAluminum (Al) has been reported to induce testicular injury via oxidative stress. Ananas comosus stem extract is an inexpensive byproduct waste rich in bromelain which is a group of sulfur-containing enzymes known for its biological activities and medicinal applications. So, the current investigation aims to evaluate the efficacy of bromelain in counteracting oxidative injury and testicular dysfunction stimulated by aluminum in rats.METHODSMale adult Wistar rats were divided into four groups. The first group used as control, however, the second and third groups were received bromelain (250 mg/kg) and AlCl₃ (34 mg/Kg, 1/25 LD₅₀), and the fourth group supplemented with bromelain one hour before AlCl₃ intoxication, respectively. Bromelain was administered daily while AlCl₃ was given every other day by oral gavages for one month.RESULTSAl intoxicated animals revealed an elevation in lipid peroxidation (TBARS and H₂O₂) level and lactate dehydrogenase (LDH) activity. However, reduced glutathione (GSH) and protein contents, antioxidant enzymes (SOD, CAT, GPx, GR, GST), phosphatases (ALP, AcP) and aminotransferases (AST, ALT) activities were significantly reduced. Additionally, considerable amendments in hormonal levels (testosterone, luteinizing and follicle-stimulating hormone) and sperm characteristics were spotted. Further, histological variations in the testes section were detected and this supports the biochemical observations. Otherwise, rats supplemented with bromelain alone diminished TBARS and H₂O₂ and augmented mostly other parameters. Furthermore, supplementation with bromelain before Al intoxication in rats exhibited worthy betterment in oxidative stress markers, hormones, and sperm quality compared to Al treated group.CONCLUSIONIn conclusion, bromelain had a powerful protective role against Al-induced testicular dysfunction so, it represents a novel approach in metal toxicity processing.     

Altered testicular microsomal steroidogenic enzyme activities in rats with lifetime exposure to soy isoflavones

Androgen production in the testis is carried out by the Leydig cells, which convert cholesterol into androgens. Previously, isoflavones have been shown to affect serum androgen levels and steroidogenic enzyme activities. In this study, the effects of lifelong exposure to dietary soy isoflavones on testicular microsomal steroidogenic enzyme activities were examined in the rat. F1 male rats were obtained from a multi-generational study where the parental generation was fed diets containing alcohol-washed soy protein supplemented with increasing amounts of Novasoy, a commercially available isoflavone supplement. A control group was maintained on a soy-free casein protein-based diet (AIN93G). The diets were designed to approximate human consumption levels and ranged from 0 to 1046.6 mg isoflavones/kg pelleted feed, encompassing exposures representative of North American and Asian diets as well as infant fed soy-based formula. Activities of testicular 3β-hydroxysteroid dehydrogenase (3β-HSD), P450c17 (CYP17), 17β-hydroxysteroid dehydrogenase (17β-HSD) were assayed on post natal day (PND) 28, 70, 120, 240 and 360 while 5-reducatase was assayed on PND 28. At PND 28, 3β-HSD activity was elevated by approximately 50% in rats receiving 1046.6 mg total isoflavones/kg feed compared to those on the casein only diet. A similar increase in activity was observed for CYP17 in rats receiving 235.6 mg total isoflavones/kg feed, a level representative of infant exposure through formula, compared to those receiving 0 mg isoflavones from the casein diet. These results demonstrate that rats fed a mixture of dietary soy isoflavones showed significantly altered enzyme activity profiles during development at PND 28 as a result of early exposure to isoflavones at levels obtainable by humans.     

Effects of dietary aluminum source and concentration on mineral status of feeder lambs

A 100 d experiment was conducted to determine the effects of aluminum (Al) source and concentration on mineral status, emphasizing phosphorus (P), of 50 feeder lambs. Six treatments, fed at 10% of the total diet, were formulated using two sources of Al, AlCl₃ and an Al-based water treatment residual (WTR, 11.1% Al), with varying levels of Al and P: (1) control (10% sand, C), (2) low WTR (2.5% WTR and 7.5% sand, L-WTR), (3) AlCl₃ with added P (1% AlCl₃, 9% sand, and 0.4% P, AlCl₃ + P), (4) high WTR (10% WTR, H-WTR), (5) AlCl₃ (1% AlCl₃ and 9% sand, AlCl₃), and (6) high WTR with added P (10% WTR and 0.4% P, H-WTR + P). The total Al varied from 0.037 to 1.2% among diets. Only lambs fed the high WTR diet without P supplementation (H-WTR) decreased feed intakes. These lambs consumed about half as much feed as lambs on all the other treatments, and had lower (P < 0.05) BW from d 84 on. Lambs receiving the H-WTR had the lowest bone Ca, P and Mg concentrations (fresh basis, mg/cm³) and lowest bone mineral content (BMC) as determined by radiographs (mm of Al). Results for the lambs on H-WTR were confounded by the greatly reduced feed intake of animals on this treatment. Plasma P decreased in all lambs consuming Al, regardless of Al source, but the effects were less severe in animals provided additional P supplementation (AlCl₃ + P and H-WTR + P). Apparent absorption of P was affected by concentration and source of Al in two metabolism trials (n = 42) beginning on d 34 and d 70, respectively. In the first trial, d 34, lambs receiving AlCl₃ treatment had reduced apparent P absorption, −17.7% (P < 0.05), when compared to all other treatments. In the d 70 trial, lambs receiving both AlCl₃ and H-WTR treatments were negatively impacted (P < 0.05) compared to the control, −20.9 and −2.5% apparent P absorption, respectively, but were no longer different from one another (P > 0.05). Diets containing 1.2% Al as WTR without P supplementation depressed feed intakes, weight gains, plasma P concentrations (P < 0.05), and BMC. However, given adequate P supplementation, even lambs consuming this amount of Al did not suffer detrimental effects, as lambs on H-WTR + P did not differ from the control (P > 0.05) in feed intakes, weight gains, or BMC.     

Effects of dietary L-carnitine and coenzyme Q10 supplementation on performance and ascites mortality of broilers

The study was conducted to determine the effects of dietary L-carnitine and coenzyme Q10 (CoQ10) supplementation on growth performance and ascites mortality of broilers. A 3 x 3 factorial arrangement was employed with three levels (0, 75 and 150 mg/kg) of L-carnitine and three levels of CoQ10 (0, 20 and 40 mg/kg) supplementation during the experiment. Five hundred and forty one-day-old Arbor Acre male broiler chicks were randomly allocated into nine groups with six replicates each. All birds were fed with the basal diets from day 1 to 7 and changed to the experimental diets from day 8. During day 15 to 21 all the birds were exposed to low ambient temperature (15-18 degrees C) to induce ascites. The results showed that under this condition, growth performance of broilers were not significantly affected by CoQ10 or L-carnitine + CoQ10 supplementation during week 0-3 and 0-6, but body weight gain (BWG) of broilers was significantly reduced by 150 mg/ kg L-carnitine during week 0-6. Packed cell volume (PCV) of broilers was significantly decreased by L-carnitine and L-carnitine + CoQ10 supplementation (P < 0.05). Erythrocyte osmotic fragility (EOF), ascites heart index (AHI) and ascites mortality of broilers were significantly decreased by L-carnitine, CoQ10 and L-carnitine + CoQ10 supplementation. Though no significant changes were observed in total antioxidative capability (T-AOC), total superoxide dismutase (T-SOD) was increased by L-carnitine, CoQ10 and L-carnitine + CoQ10 supplementation (P < 0.05). Malonaldehyde (MDA) content was significantly decreased by CoQ10 and L-carnitine + CoQ10 supplementation. The results indicate that dietary L-carnitine and CoQ10 supplementation reduce ascites mortality of broilers; the reason may be partially associated with their antioxidative effects.     

Studies on the protective role of vitamin C and E against polychlorinated biphenyl (Aroclor 1254)--induced oxidative damage in Leydig cells

Free radical production and lipid peroxidation are potentially important mediators in testicular physiology and toxicology. Polychlorinated biphenyls (PCBs) are global environmental contaminants that cause disruption of the endocrine system in human and animals. The present study was conducted to elucidate the protective role of vitamin C and E against Aroclor 1254-induced changes in Leydig cell steroidogenesis and antioxidant system. Adult male rats were dosed for 30 days with daily intraperitoneal (ip) injection of 2 mg/kg Aroclor or vehicle (corn oil). One group of rats was treated with vitamin C (100 mg/kg bw/day) while the other group was treated with vitamin E (50 mg/kg bw/day) orally, simultaneously with Aroclor 1254 for 30 days. One day after the last treatment, animals were euthanized and blood was collected for the assay of serum hormones such as luteinizing hormone (LH), thyroid stimulating hormone (TSH), prolactin (PRL), triiodothyronine (T₃), thyroxine (T₄), testosterone and estradiol. Testes were quickly removed and Leydig cells were isolated in aseptic condition. Purity of Leydig cells was determined by 3β-hydroxysteroid dehydrogenase (3β-HSD) staining method. Purified Leydig cells were used for quantification of cell surface LH receptors and steroidogenic enzymes such as cytochrome P₄₅₀ side chain cleavage enzyme (P₄₅₀scc), 3β-hydroxysteroid dehydrogenase (3β-HSD) and 17β-hydroxysteroid dehydrogenase (17β- HSD). Leydig cellular enzymatic antioxidants superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), γ-glutamyl transpeptidase (γ-GT), glutathione-S-transferase (GST) and non-enzymatic antioxidants such as vitamin C and E were assayed. Lipid peroxidation (LPO) and reactive oxygen species (ROS) were also estimated in Leydig cells. Aroclor 1254 treatment significantly reduced the serum LH, TSH, PRL, T₃, T₄, testosterone and estradiol. In addition to this, Leydig cell surface LH receptors, activities of the steroidogenic enzymes such as cytochrome P₄₅₀scc, 3β-HSD, 17β-HSD, antioxidant enzymes SOD, CAT, GPX, GR, γ-GT, GST and non-enzymatic antioxidants such as vitamin C and E were significantly diminished whereas, LPO and ROS were markedly elevated. However, the simultaneous administration of vitamin C and E in Aroclor 1254 exposed rats resulted a significant restoration of all the above-mentioned parameters to the control level. These observations suggest that vitamin C and E have ameliorative role against adverse effects of PCB on Leydig cell steroidogenesis.     

Role of α‐tocopherol and Lactobacillus plantarum in the alleviation of mercuric chloride‐induced testicular atrophy in rat's model: Implication of molecular mechanisms

The present work was aimed to evaluate the protective effects of alpha‐tocopherol (α‐toco) and/or Lactobacillus plantarum (LCB) against testicular atrophy induced by mercuric chloride (MCH). Rats were injected with 5 mg/kg MCH for 5 days consecutively, then treated with 100 mg/kg α‐toco and 6 × 10¹⁰ CFU 1.8701/kg LCB alone or together for 3 weeks. The MCH elevated serum TNF‐α, IL‐ 6, caspase‐3, and testicular malondialdehyde. However, serum testosterone, dehydroepiandrosterone, testicular messenger RNA of a steroidogenic acute regulatory protein, 17‐β‐hydroxysteroid dehydrogenase, 3β‐hydroxysteroid dehydrogenase, glutathione level, and superoxide dismutase activity were decreased. Protein expression of Nrf2 was downregulated whereas that of Bax and DNA fragmentation was upregulated in the testicular tissues. Treatment with α‐toco and LCB ameliorated the deviated biochemical parameters and improved tissue injury. It was concluded that the combination of LCB and α‐toco achieved promising results in the amelioration of MCH‐induced testicular atrophy. Nrf2, Bax expressions, and DNA fragmentation are involved in the testicular atrophy induced by MCH.     

Ellagic acid improved diabetes mellitus-induced testicular damage and sperm abnormalities by activation of Nrf2

Diabetes mellitus induces testicular damage, increases sperm abnormalities, and impairs reproductive dysfunction due to induction of endocrine disturbance and testicular oxidative stress. This study evaluated the reproductive protective effect of ellagic acid (EA) against testicular damage and abnormalities in sperm parameters in Streptozotocin (STZ)-induced diabetic rats (T1DM) and examined some possible mechanisms of protection. Adult male rats were segregated into 5 groups (n = 12 rat/each) as control, control + EA (50 mg/kg/day), T1DM, T1DM + EA, and T1DM + EA + brusatol (an Nrf-2 inhibitor) (2 mg/twice/week). All treatments were conducted for 12 weeks, daily. EA preserved the structure of the seminiferous tubules, prevented the reduction in sperm count, motility, and viability, reduced sperm abnormalities, and downregulated testicular levels of cleaved caspase-3 and Bax in diabetic rats. In the control and diabetic rats, EA significantly increased the circulatory levels of testosterone, reduced serum levels of FSH and LH, and upregulated Bcl-2 and all steroidogenic genes (StAr, 3β-HSD1, and 11β-HSD1). Besides, it reduced levels of ROS and MDA but increased levels of GSH and MnSOD and the transactivation of Nrf2. All these biochemical alterations induced by EA were associated with increased activity and nuclear accumulation of Nrf2. However, all these effects afforded by EA were weakened in the presence of brusatol. In conclusion, EA could be an effective therapy to alleviated DM-induced reproductive toxicity and dysfunction in rats by a potent antioxidant potential mediated by the upregulation of Nrf2.     

Effects of the administration routes and chemical forms of aluminum on aluminum accumulation in rat brain

An experimental rat model of aluminum accumulation in the brain was developed to aid in determining neurotoxity of aluminum (Al). Al was administered orally, intravenously, and intraperitoneally, in the absence or presence of citric acid or maltol. Oral administration of Al hydroxide [Al (OH)₃] or aluminum chloride (AlCl₃) with citric acid for 7 wk was not found to increase brain Al levels. Similarly, a single intravenous injection of AlCl₃ in the presence or absence of either citric acid or maltol did not alter brain Al levels after 48 h. Only daily intraperitoneal injections of AlCl₃ (8 mg Al/kg body weight) and an equimolar amount of maltol over a 14-d period enhanced accumulation of Al in rat brain. No significant increases were observed for the experimental groups receiving intraperitoneal AlCl₃ alone or with citric acid. This result suggests that the chemical form of Al strongly influences its bioavailability and that intraperitoneal administration of the Al-maltol complex appears to be useful in creating subacute model of Al accumulation in brain tissue.     

Aluminum toxicity related to SOD and expression of presenilin and CREB in Bombyx mori

Aluminum (Al) is an important environmental metal factor that can be potentially associated with pathological changes leading to neurotoxicity. The silkworm, Bombyx mori, is an important economic insect and has also been used as a model organism in various research areas. However, the toxicity of Al on silkworm physiology has not been reported. Here, we comprehensively investigate the toxic effects of Al on the silkworm, focusing on its effects on viability and development, superoxide dismutase (SOD) activity, and the expression of presenilin and cAMP response element‐binding protein (CREB) in BmE cells and silkworm larvae. BmE cell viability decreased after treatment with aluminum chloride (AlCl₃) in both dose‐ and time‐dependent manners. When AlCl₃ solution was injected into newly hatched fifth instar larvae, both larval weight gain and survival rate were significantly decreased in a manner correlating with AlCl₃ dose and developmental stage. Furthermore, when BmE cells and silkworm larvae were exposed to AlCl₃, SOD activity decreased significantly relative to the control group, whereas presenilin expression increased more than twofold. Additionally, CREB and phosphorylated CREB (p‐CREB) expression in the heads of fifth instar larvae decreased by 28.0% and 50.0%, respectively. These results indicate that Al inhibits the growth and development of silkworms in vitro and in vivo, altering SOD activity and the expressions of presenilin, CREB, and p‐CREB. Our data suggest that B. mori can serve as a model animal for studying Al‐induced neurotoxicity or neurodegeneration.     

Effects of dietary L-carnitine and coenzyme Q10 at different supplemental ages on growth performance and some immune response in ascites-susceptible broilers

Effects of dietary L-carnitine and coenzyme Q10 (CoQ10) at different supplemental ages on performance and some immune response were investigated in ascites-susceptible broilers. A 3 x 2 x 2 factorial design was used consisting of L-carnitine supplementation (0, 75, and 100 mg/kg), CoQ10 supplementation (0 and 40 mg/kg) and different supplemental ages (from day 1 on and from day 10 on). A total of 480 one-day-old Arbor Acre male broiler chicks were randomly allocated to 12 groups, every group had five replicates, each with eight birds. The birds were fed a corn-soybean based diet for six weeks. From day 10-21, all the birds were exposed to a low ambient temperature (12-15 degrees C) to increase the susceptibility to ascites. No significant effects were observed on growth performance by L-carnitine, CoQ10 supplementation, and different supplemental ages. Packed cell volume was significantly decreased by L-carnitine supplementation alone, and ascites heart index and ascites mortality were decreased by L-carnitine, CoQ10 supplementation alone, and L-carnitine + CoQ10 supplementation together (p < 0.05). Heart index of broilers was significantly improved by L-carnitine, CoQ10 supplementation alone during 0-3 week. Serum IgG content was improved by L-carnitine supplementation alone (p < 0.05), but lysozyme activity was increased by L-carnitine + CoQ10 supplementation together (p < 0.05). A significant L-carnitine by supplemental age interaction was observed in lysozyme activity. L-carnitine supplementation alone had no effects on the peripheral blood lymphocyte (PBL) proliferation in response to concanavalin A (ConA) and lipopolysaccharide, but supplemental CoQ10 alone and L-carnitine+ CoQ10 together decreased the PBL proliferation in response to ConA (p < 0.05). The present study suggested that L-carnitine + CoQ10 supplementation together had positive effects on some immune response of ascites-susceptible broilers, which might benefit for the reduction of broilers' susceptibility to ascites.     

Pomegranate juice moderates anxiety- and depression-like behaviors in AlCl3-treated male mice

PurposeAluminum trichloride (AlCl₃) exposure was proven to encourage some behavioral deficits and eventually induces anxiety and depression in rodents animals. Therefore, this experiment aimed to scout about the effects of pomegranate juice on anxiety- and depression-like behaviors caused by AlCl₃ in male mice.MethodsSix groups of male mice were administrated orally for 35 days by PJ and AlCl3. The control group (G-I) received tap water, while the PJ groups (G-II and G-III) were treated with 20 % and 40 % PJ, respectively. The AlCl₃ group (G-IV) was treated with 400 mg/kg/day of AlCl_3, and the last two groups (G-V and G-VI) were treated with AlCl₃ and 20 % PJ or 40 % PJ, respectively. Then, the open-field (O-F), elevated plus maze (EPM), tail suspension (TS), forced swimming (FS), and light/dark box (L/DB) tests were applied for anxiety- and depression-like behavior studies. In addition, neurotransmitters and oxidative parameters in the brain were evaluated. The plasma cortisol was measured at the end of the experiment.ResultsBehavioral analyses showed that PJ inhibited AlCl₃-induced depressive and anxiogenic effects in the O-F, EPM, TS, FS, L/DB tests. In addition, neurochemical results indicated that PJ at 20 % concentration minimized the AlCl₃ toxicity on dopamine (DOP), serotonin (SER), and acetylcholinesterase (AChE) levels in the for-brain of male mice. Moreover, PJ moderated the AlCl₃ effects by decreasing the level of thiobarbituric acid reactive substances (TBARS), and enhancing catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST) and glutathione (GSH) activities. The plasma cortisol increased in male mice treated with AlCl3 and in a group treated with a high dose of PJ.ConclusionOur results proposed that the anxiety- and depression-like behaviors induced by AlCl₃ exposure in male mice can be ameliorated by PJ treatment, probably through the inhibition of oxidative damage and minimizing the changes in neurotransmitters and hormonal activity.     

Aluminum Trichloride Inhibited Osteoblastic Proliferation and Downregulated the Wnt/β-Catenin Pathway

Aluminum (Al) exposure inhibits bone formation. Osteoblastic proliferation promotes bone formation. Therefore, we inferred that Al may inhibit bone formation by the inhibition of osteoblastic proliferation. However, the effects and molecular mechanisms of Al on osteoblastic proliferation are still under investigation. Osteoblastic proliferation can be regulated by Wnt/β-catenin signaling pathway. To investigate the effects of Al on osteoblastic proliferation and whether Wnt/β-catenin signaling pathway is involved in it, osteoblasts from neonatal rats were cultured and exposed to 0, 0.4 mM (1/20 IC₅₀), 0.8 mM (1/10 IC₅₀), and 1.6 mM (1/5 IC₅₀) of aluminum trichloride (AlCl₃) for 24 h, respectively. The osteoblastic proliferation rates; Wnt3a, lipoprotein receptor-related protein 5 (LRP-5), T cell factor 1 (TCF-1), cyclin D1, and c-Myc messenger RNA (mRNA) expressions; and p-glycogen synthase kinase 3β (GSK3β), GSK3β, and β-catenin protein expressions indicated that AlCl₃ inhibited osteoblastic proliferation and downregulated Wnt/β-catenin signaling pathway. In addition, the AlCl₃ concentration was negatively correlated with osteoblastic proliferation rates and the mRNA expressions of Wnt3a, c-Myc, and cyclin D1, while the osteoblastic proliferation rates were positively correlated with mRNA expressions of Wnt3a, c-Myc, and cyclin D1. Taken together, these findings indicated that AlCl₃ inhibits osteoblastic proliferation may be associated with the inactivation of Wnt/β-catenin signaling pathway.     

Effects of Norepinephrine on Immune Functions of Cultured Splenic Lymphocytes Exposed to Aluminum Trichloride

The aim of this study was to investigate the effect of norepinephrine (NE) on spleen lymphocytes exposed to aluminum trichloride (AlCl₃). In this experiment, lymphocytes were isolated from spleens of healthy Wistar rats weighing about 130 g and cultured with RPMI-1640 medium containing the final concentration of 0.552 mmol/L AlCl₃. NE was added to the cultured cells at the final concentrations of 0 (control group), 0.1 (low-dose group), 1 (mid-dose group), and 10 (high-dose group)?nmol/L. No addition of both AlCl₃ and NE serviced as blank (BG). The T lymphocyte proliferation; the contents of IL-2, TNF-α, and T lymphocyte subsets; immunoglobulin G (IgG) and intracellular cyclic adenosine monophosphate (cAMP) concentrations; and β₂-adrenergic receptor (β₂-AR) density were measured at the end of the culture. The result showed that NE decreased T lymphocyte proliferation and the contents of IL-2, TNF-α, and T lymphocyte subsets whereas increased the concentrations of IgG and intracellular cAMP and β₂-AR density of the lymphocyte exposed to AlCl₃. AlCl₃ exposure without adding NE showed the similar impacts on these measures compared with BG. The results suggested that NE aggravated AlCl₃ immunotoxicity on the lymphocytes and disordered the immune functions of the lymphocyte through the β₂-AR-cAMP signal pathway.     

Evaluation of the neuroprotective effects of electromagnetic fields and coenzyme Q10 on hippocampal injury in mouse

Electromagnetic fields (EMFs) are reported to interfere with chemical reactions involving free radical production. Coenzyme Q₁₀ (CoQ10) is a strong antioxidant with some neuroprotective activities. The purpose of this study was to examine and compare the neuroprotective effects of EMF and CoQ10 in a mouse model of hippocampal injury. Hippocampal injury was induced in mature female mice (25–30 g), using an intraperitoneal injection of trimethyltin hydroxide (TMT; 2.5 mg/kg). The experimental groups were exposed to EMF at a frequency of 50 Hz and intensity of 5.9 mT for 7 hr daily over 1 week or treated with CoQ10 (10 mg/kg) for 2 weeks following TMT injection. A Morris water maze apparatus was used to assess learning and spatial memory. Nissl staining and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) tests were also performed for the histopathological analysis of the hippocampus. Antiapoptotic genes were studied, using the Western blot technique. The water maze test showed memory improvement following treatment with CoQ10 and coadministration of CoQ10 + EMF. The Nissl staining and TUNEL tests indicated a decline in necrotic and apoptotic cell count following treatment with CoQ10 and coadministration of CoQ10 + EMF. The Western blot study indicated the upregulation of antiapoptotic genes in treatment with CoQ10, as well as coadministration. Also, treatment with EMF had no significant effects on reducing damage induced by TMT in the hippocampus. According to the results, EMF had no significant neuroprotective effects in comparison with CoQ10 on hippocampal injury in mice. Nevertheless, coadministration of EMF and CoQ10 could improve the neuroprotective effects of CoQ10.     

Developmental pattern of Δ5 3β-hydroxysteroid dehydrogenase activity in isolated rat Leydig cells

A direct method for determination of Δ⁵ 3β-hydroxysteroid dehydrogenase (3β-HSD) activity was employed in isolated Leydig cells (LC) derived from rats on fetal day 19 (F₁₉) and postnatal (N) days 1,12,24, 34 and 45 and adults. The activity of 3β-HSD in the adult LC was 1.15 ± 0.02 (μmole/μg DNA/hr, mean ± SEM, n = 73). Activities in the other groups, expressed as a percentage of the respective adult control, were: F₁₉-38%; N₁-39%; N₁₂-8%; N₂₄-89%; N₃₄-166%; and N₄₅-118%. A good correlation was found between histochemical staining for 3β-HSD and the quantitive method employed. Using (³H)-DHA as a substrate, LC isolated from F₁₉, n₁ and N₁₂ produced testosterone in appreciable amounts (41%, 55% and 20% of the toal products respectively) whereas at advanced stages of development (N₂₄ to adulthood) the major product was androstenedione (93 ± 1%). These findings may be explained by the observed decrease in 17β-hydroxysteroid dehydrogenase (17β-HSD) activity, due to an insufficient supply of NADPH, in the older vs. earlier stages of development. This study indicates the presence of steroidogenic enzymatic activity in LC throughout development in the rat. It also provides a relatively simple in vitro model for studies of testicular regulation during development.     

High Content of Lead Is Associated with the Softness of Drinking Water and Raised Cardiovascular Morbidity: A Review

Although aluminum chronic neurotoxicity is well documented, there are no well-established experimental protocols of Al exposure. In the current study, toxic effects of sub-chronic Al exposure have been evaluated in outbreed male rats (gastrointestinal administration). Forty animals were used: 10 were administered with AlCl₃ water solution (2 mg/kg Al per day) for 1 month, 10 received the same concentration of AlCl₃ for 3 month, and 20 (10 per observation period) saline as control. After 30 and 90 days, the animals underwent behavioral tests: open field, passive avoidance, extrapolation escape task, and grip strength. At the end of the study, the blood, liver, kidney, and brain were excised for analytical and morphological studies. The Al content was measured by inductively coupled plasma mass-spectrometry. Essential trace elements—Co, Cr, Cu, Fe, Mg, Mn, Mo, Se, and Zn—were measured in whole blood samples. Although no morphological changes were observed in the brain, liver, or kidney for both exposure terms, dose-dependent Al accumulation and behavioral differences (increased locomotor activity after 30 days) between treatment and control groups were indicated. Moreover, for 30 days exposure, strong positive correlation between Al content in the brain and blood for individual animals was established, which surprisingly disappeared by the third month. This may indicate neural barrier adaptation to the Al exposure or the saturation of Al transport into the brain. Notably, we could not see a clear neurodegeneration process after rather prolonged sub-chronic Al exposure, so probably longer exposure periods are required.