Developmental alternations in offspring of female rats orally intoxicated by aluminum chloride or lactate during gestation

Neurobehavioral and Immunohistochemical Studies of the Cerebral Cortex Following Treatment with Ethyl Acetate Leaf Fraction of Tamarindus indica During Prenatal Aluminum Chloride Exposure in Wistar Rats

Purpose

The recent increase in aluminum exposure and its effect on the development of the brain call for serious attention. The study investigated the behavioral and immunohistochemical changes in the cerebral cortex of Wistar rats following prenatal co-administration of ethyl acetate leaf fraction of Tamarindus indica (EATI) and aluminum chloride (AlCl3).

Methods

Pregnant Wistar rats were divided into 5 groups (n=4). Group I (negative control), Group II-V were experimental groups treated with 200 mg/kg of AlCl3 s/c. Group III and IV received an additional 400 mg/kg and 800 mg/kg of EATI respectively, while Group V received an additional 300 mg/kg of Vitamin E for 14 days (prenatal days 7-21) via the oral route. The pups were then exposed to cliff avoidance, negative geotaxis, and elevated plus maze (EPM) test on the post-natal day (PoND) 4-6, 7-10, and 18 respectively. On PoND 21 pups were sacrificed, and the skull dissected to remove the brain. The harvested brain tissues were processed for Cresyl fast (CF) and glial fibrillary acid protein (GFAP).

Results

The study showed that EATI administration during AlCl3 exposure was associated with significant improvement in sensory-motor development. The EPM, CF, and GFAP results revealed significant improvement in anxiety-like behavior, motor activities, GFAP expression, pyramidal cell count, and Nissl staining following prenatal EATI administration during AlCl3 exposure.

Conclusion

The present study concludes that EATI was associated with some protective potential during prenatal AlCl3 exposure in Wistar rats.

Next-generation GRAB sensors for monitoring dopaminergic activity in vivo

Dopamine (DA) plays a critical role in the brain, and the ability to directly measure dopaminergic activity is essential for understanding its physiological functions. We therefore developed red fluorescent G-protein-coupled receptor-activation-based DA (GRABDA) sensors and optimized versions of green fluorescent GRABDA sensors. In response to extracellular DA, both the red and green GRABDA sensors exhibit a large increase in fluorescence, with subcellular resolution, subsecond kinetics and nanomolar-to-submicromolar affinity. Moreover, the GRABDA sensors resolve evoked DA release in mouse brain slices, detect evoked compartmental DA release from a single neuron in live flies and report optogenetically elicited nigrostriatal DA release as well as mesoaccumbens dopaminergic activity during sexual behavior in freely behaving mice. Coexpressing red GRABDA with either green GRABDA or the calcium indicator GCaMP6s allows tracking of dopaminergic signaling and neuronal activity in distinct circuits in vivo.

Aluminum reproductive toxicity: a summary and interpretation of scientific reports

Publications addressing aluminum (Al)-induced reproductive toxicity were reviewed. Key details were compiled in summary tables. Approximate systemic Al exposure, a measure of bioavailability, was calculated for each exposure, based on the Al percentage in the dosed Al species, Al bioavailability, and absorption time course reports for the exposure route. This was limited to laboratory animal studies because no controlled-exposure human studies were found. Intended Al exposure was compared to unintended dietary Al exposure. The considerable and variable Al content of laboratory animal diets creates uncertainty about reproductive function in the absence of Al. Aluminum-induced reproductive toxicity in female mice and rats was evident after exposure to ≥25-fold the amount of Al consumed in the diet. Generally, the additional daily Al systemic exposure of studies that reported statistically significant results was greater than 100-fold above the typical human daily Al dietary consumption equivalent. Male reproductive endpoints were significantly affected after exposure to lower levels of Al than females. Increased Al intake increased fetus, placenta, and testes Al concentrations, to a greater extent in the placenta than fetus, and, in some cases, more in the testes than placenta. An adverse outcome pathway (AOP) was constructed for males based on the results of the reviewed studies. The proposed AOP includes oxidative stress as the molecular initiating event and increased malondialdehyde, DNA and spermatozoal damage, and decreased blood testosterone and sperm count as subsequent key events. Recommendations for the design of future studies of reproductive outcomes following exposure to Al are provided.

A highly sensitive fluorescent sensor for Al3+and Zn2+based on a diarylethene salicylhydrazide Schiff base derivative and its bioimaging in live cells

A new photochromic diarylethene based sensor with a salicylhydrazide Schiff base displayed a dual-mode with a “turn on” fluorescence response and color changes upon addition of Al³⁺or Zn²⁺.

A differentially selective molecular probe for detection of trivalent ions (Al3+, Cr3+and Fe3+) upon single excitation in mixed aqueous medium

A chemosensor was developed which could selectively detect and differentiate trivalent metal ions (Al³⁺, Cr³⁺and Fe³⁺) upon single excitation at two different wavelengths in aqueous medium.

A study of the distribution of aluminium in human placental tissues based on alkaline solubilization with determination by electrothermal atomic absorption spectrometry

Aluminium (Al) is a nonessential element known to induce neurotoxic effects, such as dialysis dementia, in patients on hemodialysis, with compromised kidney function. The role of Al in the progression of some neurodegenerative diseases, such as Alzheimer's disease (AD), is controversial, and remains unclear. The effects of Al on other vulnerable populations, such as fetuses and infants, have been infrequently studied. In the present study, Al has been measured in human placenta samples, comprising ∼160 each of placenta bodies, placenta membranes, and umbilical cords, using electrothermal atomic absorption spectrometry (ETAAS) after atmospheric pressure digestion with tetramethylammonium hydroxide (TMAH) and ethylenediaminetetraacidic acid (EDTA). The sensitivity, or characteristic mass (m(0)), for Al at the 309.3-nm line was found to be 30 ± 4 pg. The instrumental detection limit (IDL) (3s) for Al in solution was calculated as 0.72 μg L(-1) while the method detection limit (MDL) (3s) was 0.25 μg g(-1). Accuracy was assessed through analysis of quality control (QC) materials, including certified reference materials (CRMs), in-house reference materials (RMs), and spike recovery experiments, of varying matrices. Placental tissue analyses revealed geometric mean concentrations of approximately 0.5 μg g(-1) Al in placenta bodies (n = 165) and membranes (n = 155), while Al concentrations in umbilical cords (n = 154) were about 0.3 μg g(-1). Al was detected in 95% of placenta bodies, and 81% of placenta membranes, but only in 46% of umbilical cords.

Toxicity of leather tanning wastewater effluents in sea urchin early development and in marine microalgae

This study was designed to investigate the composition and the toxicity of leather tanning wastewater and conditioned sludge collected at the leather tanning wastewater treatment plant (CODISO) located in Solofra, Avellino (Southern Italy). Samples were analyzed for their conventional parameters (COD, TSS, chromium and ammonia) and for metal content. Effluent samples included raw wastewater, and samples collected following coagulation/flocculation process and biological treatment. A set of toxicity endpoints were tested using sea urchin and marine microalgal bioassays by evaluating acute embryotoxicity, developmental defects, changes in sperm fertilization success and transmissible damage from sperm to the offspring, and changes in algal growth rate. Dose-related toxicity to sea urchin embryogenesis and sperm fertilization success was exerted by effluent or sludge samples according to the following rank: conditioned sludge > coagulated effluent > or = raw influent >> effluent from biological treatment. Offspring quality was not affected by sperm exposure to any wastewater or to sludge samples. Algal growth was inhibited by raw or coagulated effluent to a similar extent and, again, the effluent from the biological treatment resulted in a decreased toxicity. The results suggest that coagulated effluent and conditioned sludge result in higher toxicity than raw influent in sea urchin embryos and sperm, whereas the biological wastewater treatment of coagulated effluent, in both sea urchins and algae, cause a substantial improvement of wastewater quality. Hence a final biological wastewater treatment should be operated to minimize any environmental damage from tannery wastewater.

Concurrent exposure to aluminum and stress during pregnancy in rats: Effects on postnatal development and behavior of the offspring

The present study was conducted to assess the potential combined influence of maternal restraint stress and aluminum (Al) exposure on postnatal development and behavior in the offspring of exposed rats. Female rats were concurrently exposed to 0 (control group), 50 or 100 mg/kg/day of Al administered as Al nitrate nonahydrate in drinking water with citric acid (355 or 710 mg/kg/day) for a period of 15 days prior to mating with untreated males. Aluminum exposure was maintained throughout the gestational, lactational and post-weaning periods. On days 6-20 of gestation, one-half of the pregnant animals in each group were restrained for 2 h/day. Food consumption and maternal body weight were decreased in the groups exposed to restraint only or combined with the highest Al dose. All of the animals were allowed to deliver and wean their offspring. The pups were evaluated for physical development and neuromotor maturation. Moreover, open-field activity, passive avoidance, and spatial learning in a water maze were also determined on postnatal days 30, 35 and 60, respectively. Body weight of pups treated with 100 mg/kg/day of Al was decreased relative to controls from postnatal day 12 through 21, sexual maturation was delayed in Al treated females and in males exposed to 100 mg/kg/day. Forelimb grip strength was reduced in males exposed to 100 mg/Al/kg/day and in females exposed to this Al dose plus prenatal restraint. Learning in a passive avoidance task indicated facilitated performance for Al treated rats at 100 mg/kg/day combined with prenatal restraint as evidenced by longer avoidance latencies, while learning in a water maze task showed a shorter latency to find the platform on acquisition day 2 for Al treated rats. However, no effects of Al on water maze performance were detected during the retention probe trial in which the only effect noted was an increase in the platform quadrant swim time for the prenatal restraint group. In general terms, the results of the present study did not show a notable influence of maternal restraint on the Al-induced postnatal developmental and behavioral effects in the offspring of prenatally Al-exposed rats.

Perinatal exposure to aluminum alters neuronal nitric oxide synthase expression in the frontal cortex of rat offspring

Disturbance of the neuronal nitric oxide signaling pathway by chronic exposure to aluminum (Al) in drinking water may be a causal factor of neurological disorders in offspring. In order to investigate the relationship between Al administration and expression of neuronal nitric oxide synthase (nNOS), the numbers and distribution patterns of nNOS-immunoreactive neurons were examined in the frontal cortex of offspring after exposure to 0, 5, and 10 mM of Al in drinking water during prenatal and neonatal periods. At the bregma 0.20 level, the number of nNOS-positive neurons was significantly increased (10%) and decreased (17%) following exposure to 5 and 10 mM of Al in drinking water, respectively. The change was more severe in the upper layer than in deep layer of the cortex. In contrast, at the bregma -2.80 level, the number and distribution pattern was not significantly changed following exposure to Al. These data suggest that Al toxicity may be mediated through disturbances to the nitric oxide signaling pathway and exhibits a biphasic effect, especially in the frontal area of the cortex. In addition, the results suggest that impaired expression of nNOS plays an important role in the development of neurological syndrome caused by an exposure to Al during the early developmental stage.

Aluminium in Over-the-Counter Drugs

In the early 1970s, aluminium toxicity was first implicated in the pathogenesis of clinical disorders in patients with chronic renal failure involving bone (renal osteomalacia) or brain tissue (dialysis encephalopathy). Before that time the toxic effects of aluminium ingestion were not considered to be a major concern because absorption seemed unlikely to occur. Meanwhile, aluminium toxicity has been investigated in countless epidemiological and clinical studies as well as in animal experiments and many papers have been published on the subject. It is now commonly acknowledged that aluminium toxicity can be induced by infusion of aluminium-contaminated dialysis fluids, by parenteral nutrition solutions, and by oral exposure as a result of aluminium-containing pharmaceutical products such as aluminium-based phosphate binders or antacid intake. Over-the-counter antacids are the most important source for human aluminium exposure from a quantitative point of view. However, aluminium can act as a powerful neurological toxicant and provoke embryonic and fetal toxic effects in animals and humans after gestational exposure. Despite these facts, the patient information leaflets from European antacids that are available OTC show substantial differences regarding warnings from aluminium toxicity. It seems advisable that all patients should receive the same information on aluminium toxicity from patient information leaflets, in particular with regard to the increased absorption through concomitant administration with citrate-containing beverages and the use of such antacids during pregnancy.

Aluminium incorporation into the brain of rat fetuses and sucklings

Aluminium is highly neurotoxic and inhibits prenatal and postnatal development of the brain in humans and experimental animals. However, the incorporation of aluminium into the brain of fetuses and sucklings during gestation and lactation has not been well clarified because aluminium lacks a suitable isotope for a tracer experiment. In this study, we used 26Al (a radioisotope of aluminium with a half-life of 716,000 years) as a tracer, and measured 26Al incorporation into the brain of rat fetuses and sucklings by using accelerator mass spectrometry. 26Al (26AlCl3) was subcutaneously injected into pregnant rats and lactating rats. By day 21 of gestation, considerable amounts of the 26Al injected into the pregnant rats had been transferred to the brain and nuclear fraction (brain cell nuclei) of the rat fetuses. From day 5 to day 20 postpartum, the amounts of 26Al measured in the brain of suckling rats increased significantly. On day 20 postpartum, 26Al was found in the nuclear fraction isolated from the brain of suckling rats. It is concluded that 26Al subcutaneously injected into pregnant rats and/or lactating rats was incorporated into the brain and nuclear fraction (brain cell nuclei) of fetuses and sucklings through the transplacental passage and/or maternal milk.

Evaluation of the protective activity of deferiprone, an aluminum chelator, on aluminum-induced developmental toxicity in mice

BACKGROUND

Since deferiprone can be an effective chelating agent for the treatment of aluminum (Al) overload, in the present study we investigated whether this chelator could protect against Al-induced maternal and developmental toxicity in mice.

METHODS

A single oral dose of Al nitrate nonahydrate (1,327 mg/kg) was given on gestation day 12, the most sensitive time for Al-induced maternal and developmental toxic effects in mice. At 2, 24, 48, and 72 hr thereafter, deferiprone was given by gavage at 0 and 24 mg/kg. Cesarean sections were performed on day 18 of gestation and fetuses were examined for malformations and variations.

RESULTS

Aluminum-induced maternal toxicity was evidenced by significant reductions in body weight gain, corrected body weight change, and food consumption. Developmental toxicity was evidenced by a significant decrease in fetal weight per litter and an increase in the total number of fetuses and litters showing bone retardation. No beneficial effects of deferiprone on these adverse effects could be observed. By contrast, a more pronounced decrease in maternal weight gain and corrected body weight change, as well as a higher number of litters with fetuses showing skeletal variations was noted in the group exposed to Al nitrate and treated with deferiprone at 24 mg/kg.

CONCLUSIONS

According to the current results, deferiprone would not be effective to prevent Al-induced maternal and embryo/fetal toxicity in mice.

Does aluminum exposure of pregnant animals lead to accumulation in mothers or their offspring?

There is concern that environmental and dietary aluminum (Al) might cause developmental toxicity. To better understand this concern, we reviewed published studies which administered Al compounds to pregnant animals and measured accumulation of Al in mother, fetus, or born offspring. A total of 7 studies were identified which administered Al during gestation and evaluated fetal accumulation. Another 7 studies administered Al at least until birth and then evaluated accumulation in mothers and/or pups. These 14 studies included 4 different Al compounds (hydroxide, chloride, lactate, and citrate) administered by 4 different routes (gavage, feed, intraperitoneal injection, and subcutaneous injection) with total doses ranging from 13.5 to 8,400 mg/kg. Fetal Al levels were not increased in 6 of 7 studies and pup Al levels were not increased in 4 of 5 studies in which they were measured. Maternal Al levels were increased in some studies, but there was no consistent pattern of organ-specific accumulation and several positive studies were contradicted by subsequent reports from the same laboratory. Placental levels were increased in 6 of 9 studies and were greater than corresponding fetal levels. The weight of evidence in these studies suggests that environmental and dietary Al exposures are unlikely to pose risks of Al accumulation to pregnant animals or their fetuses.

Neurobehavioral alteration in rodents following developmental exposure to aluminum

Aluminum (Al) is one of the most abundant metals in the earth's crust, and humans can be exposed to it from several sources. It is present in food, water, pharmaceutical compounds, and in the environment, e.g., as a result of acid rain leaching it from the soil. Exposure to Al has recently been implicated in a number of human pathologies, but it has not yet been definitely proved that it plays a major causal role in any of them. In this paper we review the effects of developmental exposure of laboratory animals to Al salts as a model for human pathological conditions. The data presented show behavioral and neurochemical changes in the offspring of AL-exposed mouse dams during gestation, which include alterations in the pattern of ultrasonic vocalizations and a marked reduction in central nervous system (CNS) choline acetyltransferase activity. Prenatal Al also affects CNS cholinergic functions under Nerve Growth Factor (NGF) control, as shown by increased central NGF levels and impaired performances in a maze learning task in young-adult mice. The need for more detailed studies to evaluate the risks for humans associated with developmental exposure to Al, as well as the importance of using more than one strain of laboratory animal in the experimental design, is emphasized.

L-methionine induces stage-dependent changes of differentiation and oxidative activity in sea urchin embryogenesis

This study was to investigate developmental toxicity of some selected low molecular weight antioxidants, by utilising sea urchin embryos and gametes as model system. Sea urchin embryos or sperm were exposed at different developmental stages to L-methionine or some selected low molecular weight antioxidants: a) N-acetylcysteine; b) L-carnosine; c) L-homocarnosine, and d) L-anserine. L-methionine displayed developmental toxicity at levels > or = 10(-5) M, whereas the other agents tested were mostly active at levels > or = 10(-4) M. When embryos were exposed to 10(-4) M L-methionine or N-acetylcysteine at different developmental stages, the most severe effects were exerted by early exposures (0 to 2 hr after fertilisation), whereas later exposures turned to lesser or no effects. Cytogenetic analysis of L-methionine-exposed embryos showed a significant mitogenic effect and increase of mitotic aberrations. Fertilisation success was decreased by L-methionine (10(-6) M to 10(-3) M) added at the moment of fertilisation, with increasing developmental and cytogenetic abnormalities in the offspring. The formation of reactive oxygen species in embryos and gametes was determined by: a) analysing the DNA oxidative product, 8-hydroxy-2'-deoxyguanosine (8-OHdG), and b) luminol-dependent chemiluminescence. The results showed that: 1) 8-OHdG levels were increased during embryogenesis; 2) fertilisation was associated with a double-wave luminol-dependent chemiluminescence emission; 3) luminol-dependent chemiluminescence was maximal in cleavage, declining down to zero in plutei, and 4) an embryotoxic L-methionine or N-acetylcysteine level (10(-4) M) turned to a decrease in reactive oxygen species formation. The data suggest that L-methionine- or N-acetylcysteine-induced developmental toxicity is confined to early stages. A role for oxidative activity is suggested in modulating cell differentiation and embryogenesis, consistent with antioxidant-induced damage to early life stages.

Cebocephaly, alobar holoprosencephaly, spina bifida, and sirenomelia in a stillbirth

Cebocephaly and sirenomelia are uncommon birth defects. Their association is extremely rare; however, the presence of spina bifida with both conditions is not unexpected. We report on a female still-birth with cebocephaly, alobar holoprosencephaly, cleft palate, lumbar spina bifida, sirenomelia, a single umbilical artery, and a 46,XX karyotype, but without maternal diabetes mellitus. Our case adds to the examples of overlapping cephalic and caudal defects, possibly related to vulnerability of the midline developmental field or axial mesodermal dysplasia spectrum.

The effect of social learning on a conditioned avoidance response of rats treated prenatally with aluminum lactate

Aluminum (Al) has been proven to be a behavioral teratogenic agent in a number of experimental studies. Prenatal exposures to Al lactate have been shown to cause cognitive deficits in a variety of species. The present experiment was carried out on SPRD rat pups treated prenatally with Al lactate to determine whether observational conditioning (social learning) would reverse the impairment in learning described previously following such treatment. A conditioned avoidance response was used as an observational learning task. The results provide evidence that Al-treated pups are capable of social learning (i.e., the performance of the avoidance response improved as a result that Al-treated learning); however, the response latency of the avoidance response was not different in these animals from those that were not exposed to such facilitation, suggesting that additional factors are involved in the effects of prenatal aluminum intoxication on cognitive processes.

Oral aluminum administration during pregnancy and lactation produces gastric and renal lesions in rat mothers and delay in CNS development of their pups

The expression of the neurofilament protein of the highest molecular weight (NF-H) is developmentally and spatially regulated. For example, the MAb RMO24.9, directed against a phosphorylated epitope in the tail domain of NF-H, immunohistochemically labels specific tracts within the rat brainstem prenatally, but does not label diencephalic tracts until after postnatal day 10 (P10). A diet providing 300 mg/kg/d Al (as Al lactate) to rat dams throughout gestation causes behavioral deficits in their offspring (Bernuzzi et al., 1989). We repeated this regimen by substituting 120 mM Al lactate (pH 6.5) for drinking water during gestation and lactation, and examined the distribution of immunolabeling by RMO 24.9 after exposure to Al. Tracts within the diencephalon that bind RMO 24.9 on P11 in control pups did not bind the MAb until P14 in Al-treated pups. In these preliminary experiments, Al seemed to have caused a developmental delay in the expression of phosphorylated NF-H in the pups of mothers that received Al during gestation. However, subsequent experiments showed that the neuropathology observed--and that reported by other investigators using similar Al levels--may not be the result of the direct effects of Al on the pups. Throughout lactation, treated dams appeared progressively more cachexic. Unlike the normal viscera of pair-watered controls, the stomachs of treated dams were ulcerated, and their kidneys had decreased cortical thickness and contained stones. Lesions such as these compromise a rat's ability to absorb nutrients, to excrete toxins, and to regulate water and electrolytes. In a lactating dam, these alterations could compromise the dam's ability to nourish her pups. Our experiments point out that the mechanisms of Al toxicity-- already complex in the adult--are further complicated in a system in which the pup is dependent on the mother for delivery of both nutrients and toxins. It is therefore impossible to determine the cause of any neuropathology in the pup in a system where Al delivery overlies a background of multisystem defect and altered maternal homeostasis.

Effects of aluminum on neuronal signal transduction: mechanisms underlying disruption of phosphoinositide hydrolysis

1. Aluminum is neurotoxic in humans and animals and alters formation of inositol phosphate (IP) second messengers following in vivo or in vitro exposure. 2. Several components of the IP signalling system including G-proteins, phosphatidylinositol-specific phospholipase C (PI-PLC), protein kinase C (PKC) and Ca2+ homeostasis are susceptible to inhibition/disruption by aluminum compounds. 3. Recent evidence suggests that, despite its effects on other components, competitive inhibition by aluminum of phosphatidylinositol 4,5-bisphosphate (PIP2) hydrolysis by PI-PLC underlies its effects on agonist-stimulated IP generation.

Reproductive and developmental toxicity of aluminum: a review

It is well known that aluminum is a developmental toxicant when administered parenterally. However, until recently, there was little concern about embryo/fetal consequences of aluminum ingestion because bioavailability was considered low. The importance of the route of exposure and the chemical form of the aluminum compound on the developmental toxicity of this element are now well established. Although no evidence of maternal and embryo/fetal toxicity was observed when high doses of aluminum hydroxide were given orally to pregnant rats and mice during organogenesis, signs of maternal and developmental toxicity were found in mice when aluminum hydroxide was given concurrently with citric or lactic acids. On the other hand, studies in rabbits have shown that aluminum-induced behavioral toxicity is greater in adult and aged animals than in young adults. However, maternal dietary exposure to excess A1 during gestation and lactation which did not produce maternal toxicity would be capable of causing permanent neurobehavioral deficits in weanling mice and rats. Adverse effects of parenteral aluminum administration on the mouse male reproductive system have also been reported. The embryo/fetal toxicity of aluminum administration, the potential reproductive toxicology of aluminum exposure, and the neurodevelopmental effects of aluminum are here reviewed.

Metal-induced developmental toxicity in mammals: a review

It is well established that certain metals are toxic to embryonic and fetal tissues and can induce teratogenicity in mammals. The main objective of this paper has been to summarize the toxic effects that excesses of certain metals may cause on mammalian development. The reviewed elements have been divided into four groups: (a) metals of greatest toxicological significance (arsenic, cadmium, lead, mercury, and uranium) that are wide-spread in the human environment, (b) essential trace metals (chromium, cobalt, manganese, selenium, and zinc), (c) other metals with evident biological interest (nickel and vanadium), and (d) metals of pharmacological interest (aluminum, gallium, and lithium). A summary of the therapeutic use of chelating agents in the prevention of metal-induced developmental toxicity has also been included. meso-2,3-Dimercaptosuccinic acid (DMSA) and sodium 2,3-dimercaptopropane-1-sulfonate (DMPS) have been reported to be effective in alleviating arsenic- and mercury-induced teratogenesis, whereas sodium 4,5-dihydroxybenzene-1,3-disulfonate (Tiron) would protect against vanadium- and uranium-induced developmental toxicity.

Element variations in pregnant and nonpregnant female rats orally intoxicated by aluminum lactate

Pregnant or nonpregnant female rats were orally intoxicated by aluminum lactate (400 mg Al/kg/d) from d 0-19 of gestation to determine the treatment's influence on element variations in the females and their fetuses. The aluminum levels of plasma, liver, spleen, and kidneys were significantly higher in treated pregnant rats than non-pregnant female rats. Differences of P, Ca, Cu, Zn, or Mg levels were observed among the four groups of female rats in the tissues and plasma. The aluminum content of the 20-d-old fetuses did not significantly differ between the treated and control groups. On the contrary, calcium and magnesium levels in the whole fetuses from treated or nontreated dams are significantly different.

Classification of microphthalmos and coloboma

A new classification of microphthalmos and coloboma is proposed to bring order to the complexity of clinical and aetiological heterogeneity of these conditions. A phenotypic classification is presented which may help the clinician to give a systematic description of the anomalies. The phenotype does not predict the aetiology but a systematic description of ocular and systemic anomalies improves syndrome identification. There are two major classes, total and partial microphthalmos, and a subclassification which follows the embryology of the anomalies. The aetiological classification consists of three classes: (1) genetic (monogenic and chromosomal), (2) prenatally acquired (teratological agents and intrauterine deformations), and (3) associations. Genetic disorders give rise to malformations; prenatally acquired anomalies are disruptions or deformations. The aetiological classification can be applied to other congenital birth defects and improves counselling of families. Recurrence risks vary considerably between the classes.

Developmental patterns of aluminum in mouse brain and effects of dietary aluminum excess on manganese deficiency

Previous studies have shown that excess dietary Al during development can affect neurobehavioral measures and decrease tissue Mn of 21-day-old weanling mice without a corresponding increase in tissue Al concentrations. Al and Mn have similar tissue concentrations and similar affinities for transferrin, which is the major plasma transport protein for Al and Mn as well as Fe. In the present study, brain Al, Mn and Fe were studied at 6, 12, 18 and 24 days of age in offspring of Swiss Webster mice fed a semipurified diet containing excess Al (Al[+], 1000 micrograms Al/g diet, Al as Al lactate), marginal Mn (Mn[-], 3 micrograms Mn/g diet) or both excess Al and marginal Mn (Al[+]Mn[-]) from conception to day 24 postnatal (weaning on day 18). Brain Al concentrations were higher at 6 days of age than at later ages and were significantly elevated by the excess Al diet (P = 0.017) but returned to control levels by weaning. Brain Mn concentrations increased from day 6 to day 24 and were lower in the Mn deficient groups (P < 0.001) and also in the excess Al group (P = 0.024) than in controls. Brain Fe concentrations were not influenced by diet. Similar patterns were seen in liver as in brain. The marginal Mn diet led to postnatal growth retardation which was more severe in litters of dams fed Al[+]Mn[-] diets than in litters fed Mn[-] diet. These data suggest that excess Al in diet can interact specifically with Mn metabolism during development.

Alterations to the pattern of ultrasonic calling after prenatal exposure to aluminium sulfate

Pregnant CBA mice were exposed to aluminium sulfate at a dose of 200 mg/kg body wt injected intraperitoneally during Days 10 to 13 of gestation. We used a variety of ethological measures, which have been shown to be sensitive indicators of toxicants, to assess effects on the mother and the behavioral development of pups. Prenatal aluminium resulted in a reduction in the rate of ultrasonic calling by pups accompanied by a shift in the timing of peak calling; treated pups exhibited decreased growth and delays in neurobehavioral development. The treatment received by a pup's foster mother was also found to influence development. We recommend ultrasonic calling as a sensitive measure in studies of behavioral teratogenicity.

Holoprosencephaly: a family showing dominant inheritance and variable expression

A family with probable dominant holoprosencephaly is presented with five affected subjects in two sibships, the offspring of healthy sisters who are presumed gene carriers. Of the affected children, three had cebocephaly and died shortly after birth. One had left choanal atresia, retinal coloboma, a single central maxillary incisor, microcephaly, short stature, and learning problems. Another had only a single central maxillary incisor. The occurrence of hypotelorism, microcephaly, and unilateral cleft lip and palate as minor manifestations of the gene in possible and probable gene carriers is discussed.

Aluminum transfer through milk in female rats intoxicated by aluminum chloride

Female rats received an ip injection of aluminum chloride (10 mg Al/kg/d) during the first 12 d after parturition; this treatment led to a reduction in food intake associated with a reduction in body wt. Pups of the intoxicated dams showed a growth retardation after postnatal day 7. One day after treatment, the female rats intoxicated with aluminum had a considerably higher level of aluminum in milk than controls. The aluminum levels of plasma, liver, spleen, and kidneys were also significantly higher in treated female rats than controls. On the contrary, in the same tissues of pups from treated or not treated dams, no differences in aluminum levels were observed. No effect of aluminum treatment was detected on plasma silicon levels in dams and pups.

Effects of postnatal aluminum exposure on choline acetyltransferase activity and learning abilities in the rat

Young rats were treated by gastric intubation with aluminum lactate (0, 100, and 200 mg Al/kg/day) from postnatal days 5 to 14 to determine the treatment's influence on brain choline acetyltransferase activity and learning abilities. The results indicated that aluminum concentrations in the cerebral areas increased in parallel to plasma aluminum at the dose of 200 mg. In the same case, choline acetyltransferase activity was reduced. At postnatal days 50 and 100, the treated rats did not show alterations in their learning abilities in the 2 tests which are based on different motivations (avoidance of an aversive light or alimentary motivation) and different ways of achievement (pressing on a lever or running in a maze). A low reduction in the general activity, particularly in the radial maze test, was only observed in rats treated with 200 mg Al/kg/day.

Neurodevelopmental effect of aluminum in mice: fostering studies

In order to determine sensitive periods for induction of neurodevelopmental effects of aluminum (Al), mice were fed either 25 (control) or 1000 (high Al) micrograms Al/g diet (as Al lactate) from conception through lactation and litters were fostered either within or between groups at birth. Birth parameters were not influenced by Al intake. Food intake and body weight were 10%-12% lower during lactation in dams fed the high Al diets. Both gestation and lactation high Al exposure led to growth retardation in offspring beginning on day 10 postnatal; combined gestation and lactation exposure led to the biggest weight differential at weaning (23%). For neurobehavioral measures obtained at weaning, forelimb grasp strength was influenced by gestation high Al exposure, whereas negative geotaxis was influenced by lactation exposure, and hindlimb grasp and temperature sensitivity were influenced by both gestation and lactation exposure. Pup liver and brain manganese (Mn) and liver iron (Fe) concentrations at weaning were lower after high Al lactation exposure than in controls. Pup brain and liver Al concentrations were similar among the groups. These data show that mice are susceptible to neurodevelopmental effects of high maternal dietary Al intake during both gestation and lactation, and that high maternal intake can result in altered essential trace element metabolism in the offspring.

Long-term effects of aluminium on the fetal mouse brain

Potentially noxious substances may act as fetal teratogens at levels far lower than those required to produce detectable effects in adults, and behavioural teratogenicity may occur at levels lower than those which produce morphological teratogenesis. Aluminium (Al) is a potential neurotoxin in adults. Since pregnant women may be exposed to untoward levels of Al compounds under certain conditions, we have examined the long-term effects of treating the pregnant mouse with intraperitoneal or oral aluminium sulphate on brain biochemistry and behaviour of the offspring. The cholinergic system, as evaluated by the activity of choline acetyltransferase (ChAT), was affected differentially in different regions of the brain, and still showed significant effects in the adult. Differences between the intraperitoneal and oral series in the magnitude of effect seen in the regions of the brain probably reflect differences in the effective level of exposure. Growth rate and psychomotor maturation in the pre-weaning mouse were affected in the intraperitoneal series only, showing a marked post-natal maternal effect.

The cyclops and the mermaid: an epidemiological study of two types of rare malformation

Infants with cyclopia or sirenomelia are born at an approximate rate of 1 in 100,000 births. Eight malformation monitoring systems around the world jointly studied the epidemiology of these rare malformations: 102 infants with cyclopia, 96 with sirenomelia, and one with both conditions were identified among nearly 10.1 million births. Maternal age is somewhat increased for cyclopia, indicating the likely inclusion of some chromosomally abnormal infants which were not identified. About half of the infants are stillborn. There is a female excess among infants with cyclopia. Excess twinning occurred for cyclopia and possibly also for sirenomelia. An analysis of associated malformations indicates the similarity between the two conditions, which is in agreement with recent embryological analysis.

Developmental toxicity evaluation of oral aluminum in rats: influence of citrate

To evaluate the influence of citrate on the potential developmental toxicity of high doses of aluminum (133 mg/kg/day), three groups of pregnant Sprague-Dawley rats were given by gavage aluminum hydroxide (384 mg/kg/day), aluminum citrate (1064 mg/kg/day), or aluminum hydroxide (384 mg/kg/day) concurrent with citric acid (62 mg/kg/day) on gestational days 6 through 15. Control animals received distilled water. At termination on gestation day 20, live fetuses were examined for external, visceral, and skeletal alterations. There were no significant differences between controls and Al-treated rats on pre- or postimplantation loss, number of live fetuses per litter, or sex ratio. Fetal body weight was significantly reduced in the group treated with Al(OH)3 and citric acid. Although no increases in the incidence of malformations were observed, the incidence of skeletal variations was significantly increased in the group given Al(OH)3 concurrent with citric acid. In summary, although the administration of citric acid did not modify the lack of embryotoxicity and teratogenicity of Al(OH)3 in rats, some signs of maternal toxicity and fetotoxicity could be observed in this group.

Developmental alterations in offspring of female rats orally intoxicated by aluminum lactate at different gestation periods

Pregnant rats were treated orally with aluminum lactate (400 mg Al/kg/day) during three periods of gestation to determine the treatment's influence on mortality, weight gain, neuromotor maturation, and learning abilities of their pups. No effect of treatment on litter size, mortality rate, and weight gain of pups was detected. In the negative geotaxis test, the scores of pups from females treated during the second and third weeks of gestation were diminished. In the locomotor coordination and the operant conditioning tests, significant differences in the comparison of controls vs. the three treated groups were found, indicating long-term effects of early intoxication upon the central nervous system.