Prenatal exposure to tobacco extract containing nicotinic alkaloids produces morphological and behavioral changes in newborn rats

Fluoxetine alters rat's milk properties causing impact on offspring's development

Fluoxetine is an antidepressant used to treat several conditions including postpartum depression. This disease causes cognitive, emotional, behavioral and physical changes, negatively affecting the mother, child and family life. However, fluoxetine is excreted in breast milk, causing short and long-term effects on children who were exposed to the drug during lactation, so studies that seek to uncover the consequences of these effects are needed. Thus, the aim of this study was to evaluate the effects of fluoxetine on the nutritional characteristics of milk and on growth and neurobehavioral development of the offspring on a rat model. Lactating rats were divided into 4 groups: control group and three experimental groups, which were treated with different doses of fluoxetine (1, 10 and 20 mg/kg) during the lactation. Dams body weight and milk properties were measured, as well as offspring's growth and physical and neurobehavioral development. Results showed that the use of fluoxetine during lactation decreased dam's body weight and alters milk's properties, leading to a decrease in offspring's growth until adulthood. Therefore, the use of fluoxetine during lactation needs to be cautiously evaluated, with the benefits to the mothers and the associated risk to the offspring carefully balance.

Nicotine's effect on cognition, a friend or foe?

Tobacco smoking is a preventable cause of morbidity and mortality throughout the world. Smoking comes in form of absorption of many compounds, among which nicotine is the main psychoactive component of tobacco and its positive and negative reinforcement effects are proposed to be the key mechanism for the initiation and maintenance of smoking. Growing evidence suggests that the cognitive enhancement effects of nicotine may also contribute to the difficulty of quitting smoking, especially in individuals with psychiatric disorders. In this review, we first introduce the beneficial effect of nicotine on cognition including attention, short-term memory and long-term memory. We next summarize the beneficial effect of nicotine on cognition under pathological conditions, including Alzheimer's disease, Parkinson's disease, Schizophrenia, Stress-induced Anxiety, Depression, and drug-induced memory impairment. The possible mechanism underlying nicotine's effect is also explored. Finally, nicotine's detrimental effect on cognition is discussed, including in the prenatal and adolescent periods, and high-dose nicotine- and withdrawal-induced memory impairment is emphasized. Therefore, nicotine serves as both a friend and foe. Nicotine-derived compounds could be a promising strategy to alleviate neurological disease-associated cognitive deficit, however, due to nicotine's detrimental effect, continued educational programs and public awareness campaigns are needed to reduce tobacco use among pregnant women and smoking should be quitted even if it is e-cigarette, especially for the adolescents.

A Complete Review of Mexican Plants with Teratogenic Effects

In Mexico, the use of medicinal plants is the first alternative to treat the diseases of the most economically vulnerable population. Therefore, this review offers a list of Mexican plants (native and introduced) with teratogenic effects and describes their main alterations, teratogenic compounds, and the models and doses used. Our results identified 63 species with teratogenic effects (19 native) and the main alterations that were found in the nervous system and axial skeleton, induced by compounds such as alkaloids, terpenes, and flavonoids. Additionally, a group of hallucinogenic plants rich in alkaloids employed by indigenous groups without teratogenic studies were identified. Our conclusion shows that several of the identified species are employed in Mexican traditional medicine and that the teratogenic species most distributed in Mexico are Astragalus mollissimus, Astragalus lentiginosus, and Lupinus formosus. Considering the total number of plants in Mexico (≈29,000 total vascular plants), to date, existing research in the area shows that Mexican plants with teratogenic effects represent ≈0.22% of the total species of these in the country. This indicates a clear need to intensify the evaluation of the teratogenic effect of Mexican plants.

Moringa oleifera Seed at the Interface of Food and Medicine: Effect of Extracts on Some Reproductive Parameters, Hepatic and Renal Histology

The lipid-rich Seed of Moringa oleifera has been promoted as an effective water clarifier. Aside its vital nutritional application as an emerging food additive, the seed has continued to gain a wider acceptance in various global ethnomedicines for managing several communicable and lifestyle diseases, howbeit, its potential toxic effect, particularly on fertility and pregnancy outcomes has remained uninvestigated; the effect of Moringa oleifera seed (MOSE) aqueous-methanol extracts on fertility and pregnancy outcome, was investigated in vivo using female Wistar rats that were divided into 50, 100, 300 and 500 mg per kilogram body weight. Group six was given Moringa oleifera seed treated water ad-libitum (ad-libitum group). Organs harvested for histological assessment included ovary, uterus, liver and kidney. In addition to HPLC fingerprint and a preliminary peptide detection, we determined the physico-chemical characteristics and mineral content of MOSE using standard methods. Data were analyzed with significance at p ≤ 0.05. There was no significant difference in the estrus cycle, mating index, gestation survival index, gestation index, fertility index and sex ratio among all groups. Gestation length was reduced in some groups. While the male pup birth weight was comparable among the different groups, female pups birth weights were significantly reduced in 50 and 100 mg groups. Anogenital distance indices of female pups in ad libitum group were significantly increased. Pathologies were observed in liver and kidneys of dams while kidneys of pups presented a dose dependent reduction in the number of glomeruli. There were no observed pathological changes in the ovary and uterus. This study showed for the first time in rodents, that the lipid-rich MOSE is unsafe to the kidney of rodents while the lipid-free MOSE appears to be safe at doses up to 300 mg/kg body weight. Findings from this study suggested that the female pups were masculinized. In conclusion, the lipid-rich seed extracts of MOSE appear to be unsafe during pregnancy, induce hepatic and renal toxicity while the lipid-free MOSE excludes inherent toxicity as the hydrophobic part has been linked to toxicity as observed in this study due to the developmental programming effect on female offspring in rodents.

Effects of the aqueous extract of Phyllanthus niruri Linn during pregnancy and lactation on neurobehavioral parameters of rats' offspring

ETHNOPHARMACOLOGICAL RELEVANCE

Phyllanthus niruri L. (Phyllanthaceae) is a plant used in traditional medicine, mainly to treat kidney stones. However, the effects of maternal exposure to P. niruri remain poorly explored.

AIM OF THE STUDY

The objective of this study was to investigate the effects of administration of aqueous extract of P. niruri (AEPN) during pregnancy and lactation, in maternal toxicity, reflex maturation, and offspring memory.

MATERIALS AND METHODS

Pregnant rats were divided into three groups (n = 8/group): Control (vehicle), AEPN 75, and AEPN 150 (each respectively treated with P. niruri at a dose of 75 and 150 mg/kg/day). The animals were treated via intragastric gavage during pregnancy and lactation. Weight gain, feed intake, and reproductive performance were analyzed in the mothers. In the offspring, the following tests were performed: Neonatal Reflex Ontogeny, Open Field Habituation Test and the Object Recognition Test in adulthood.

RESULTS

Maternal exposure to AEPN did not influence weight gain, feed intake, or reproductive parameters. In the offspring, anticipation of reflex ontogenesis (time of completion) was observed (p < 0.05). During adulthood, the AEPN groups presented decreases in exploratory activity upon their second exposure to the Open Field Habituation Test (in a dose-dependent manner) (p < 0.05). In the Object Recognition Test, administration of the extract at 75 and 150 mg/kg induced significant dose-dependent improvements in short and long-term memory (p < 0.05).

CONCLUSION

Administration of the AEPN accelerated the reflex maturation in neonates, and improved offspring memory while inducing no maternal or neonatal toxicity.

Toxic effects of 1-(N-methyl-N-nitrosamino)-1-(3-pyridinyl)-4-butanal on the reproduction of female mice

Cigarette smoke can affect female reproductive health by causing follicle destruction and oocyte dysfunction. Third-hand smoke has received increasing attention as a public health issue. However, the effects of third-hand smoke on the female reproductive system, particularly the ovaries, remain unclear. 1-(N-methyl-N-nitrosamino)-1-(3-pyridinyl)-4-butanal (NNA) can be used as a biomarker of third-hand smoke. We studied the in vivo toxic effects of NNA on mice ovaries and offspring development. Three-week-old premature female mice were exposed to NNA at two different concentrations (0.075 μg/kg and 0.15 μg/kg body weight) and tap water (blank control) and diluted dimethylsulfoxide (solvent control) for 30 days. We found that oral administration of NNA (0.075 μg/kg and 0.15 μg/kg) significantly reduced ovary weight (the 0.15 μg/kg group was reduced to 18.69% ± 0.89%) and ovarian follicle number (reduced by about 30%) (p < 0.05). Consumption of 0.15 μg/kg NNA reduced the survival rate of superovulated oocytes from 91.36% to 60.55% (p < 0.05). In addition, treated female mice in each group were mated with normal male mice to observe the effects of NNA on the F1 offspring, and during mating and lactation, all groups were given tap water. Two different concentrations of NNA exposure also significantly reduced body weight and impaired ear opening, tooth eruption and eye opening in F1 offspring, especially those exposed to 0.15 μg/kg NNA (p < 0.05). Our study suggested that NNA exposure had toxic effects on the reproductive health of female mice and their offspring. The results obtained may help evaluate the risks of third-hand smoke to women's reproductive health and to the health of their offspring.

The absence of maternal pineal melatonin rhythm during pregnancy and lactation impairs offspring physical growth, neurodevelopment, and behavior

Maternal melatonin provides photoperiodic information to the fetus and thus influences the regulation and timing of the offspring's internal rhythms and preparation for extra-uterine development. There is clinical evidence that melatonin deprivation of both mother and fetus during pregnancy, and of the neonate during lactation, results in negative long-term health outcomes. As a consequence, we hypothesized that the absence of maternal pineal melatonin might determine abnormal brain programming in the offspring, which would lead to long-lasting implications for behavior and brain function. To test our hypothesis, we investigated in rats the effects of maternal melatonin deprivation during gestation and lactation (MMD) to the offspring and the effects of its therapeutic replacement. The parameters evaluated were: (1) somatic, physical growth and neurobehavioral development of pups of both sexes; (2) hippocampal-dependent spatial learning and memory of the male offspring; (3) adult hippocampal neurogenesis of the male offspring. Our findings show that MMD significantly delayed male offspring's onset of fur development, pinna detachment, eyes opening, eruption of superior incisor teeth, testis descent and the time of maturation of palmar grasp, righting reflex, free-fall righting and walking. Conversely, female offspring neurodevelopment was not affected. Later on, male offspring show that MMD was able to disrupt both spatial reference and working memory in the Morris Water Maze paradigm and these deficits correlate with changes in the number of proliferative cells in the hippocampus. Importantly, all the observed impairments were reversed by maternal melatonin replacement therapy. In summary, we demonstrate that MMD delays the appearance of physical features, neurodevelopment and cognition in the male offspring, and points to putative public health implications for night shift working mothers.

Prenatal nicotine exposure retards osteoclastogenesis and endochondral ossification in fetal long bones in rats

This study investigated the mechanisms underlying the retarded development of long bone in fetus by prenatal nicotine exposure (PNE) which had been demonstrated by our previous work. Nicotine (2.0 mg/kg.d) or saline was injected subcutaneously into pregnant rats every morning from gestational day (GD) 9 to 20. Fetal femurs or tibias were harvested for analysis on GD 20. We found massive accumulation of hypertrophic chondrocytes and a delayed formation of primary ossification center (POC) in the fetal femur or tibia of rat fetus after PNE, which was accompanied by a decreased amount of osteoclasts in the POC and up-regulated expression of osteoprotegerin (OPG) but by no obvious change in the expression of receptor activator of NF-κB ligand (RANKL). In primary osteoblastic cells, both nicotine (0, 162, 1620, 16,200 ng/ml) and corticosterone (0, 50, 250, 1250 nM) promoted the mRNA expression of OPG but concentration-dependently suppressed that of RANKL. Furthermore, blocking α4β2-nicotinic acetylcholine receptor (α4β2-nAChR) or glucocorticoid receptor rescued the above effects of nicotine and corticosterone, respectively. In conclusion, retarded osteoclastogenesis may contribute to delayed endochondral ossification in long bone in fetal rats with PNE. The adverse effects of PNE may be mediated via the direct effect of nicotine and indirect effect of maternal corticosterone on osteoblastic cells.

Camellia sinensis Prevents Perinatal Nicotine-Induced Neurobehavioral Alterations, Tissue Injury, and Oxidative Stress in Male and Female Mice Newborns

Nicotine exposure during pregnancy induces oxidative stress and leads to behavioral alterations in early childhood and young adulthood. The current study aimed to investigate the possible protective effects of green tea (Camellia sinensis) against perinatal nicotine-induced behavioral alterations and oxidative stress in mice newborns. Pregnant mice received 50 mg/kg C. sinensis on gestational day 1 (PD1) to postnatal day 15 (D15) and were subcutaneously injected with 0.25 mg/kg nicotine from PD12 to D15. Nicotine-exposed newborns showed significant delay in eye opening and hair appearance and declined body weight at birth and at D21. Nicotine induced neuromotor alterations in both male and female newborns evidenced by the suppressed righting, rotating, and cliff avoidance reflexes. Nicotine-exposed newborns exhibited declined memory, learning, and equilibrium capabilities, as well as marked anxiety behavior. C. sinensis significantly improved the physical development, neuromotor maturation, and behavioral performance in nicotine-exposed male and female newborns. In addition, C. sinensis prevented nicotine-induced tissue injury and lipid peroxidation and enhanced antioxidant defenses in the cerebellum and medulla oblongata of male and female newborns. In conclusion, this study shows that C. sinensis confers protective effects against perinatal nicotine-induced neurobehavioral alterations, tissue injury, and oxidative stress in mice newborns.

Maternal repeated oral exposure to microcystin-LR affects neurobehaviors in developing rats

Microcystins are toxic peptides secreted by certain water blooms of toxic cyanobacteria. The most widely studied microcystin is microcystin-LR (MC-LR), which exhibits hepatotoxicity and neurotoxicity. However, limited information is available regarding the effects on offspring following maternal exposure. The present study was conducted to observe the effects of progestational exposure to MC-LR on postnatal development in rats. Female Sprague-Dawley rats (28 d old) were randomly divided into a control group and 3 treatment groups (1.0 µg MC-LR/kg body wt, 5.0 µg MC-LR/kg body wt, and 20.0 µg MC-LR/kg body wt), with 7 rats per group. The MC-LR was administered through gavage once every 48 h for 8 wk. Pure water was used as control. Each female rat was mated with an unexposed adult male rat. Motor development, behavioral development, and learning ability of pups were detected using surface righting reflex, negative geotaxis, and cliff avoidance tests on postnatal day 7. Open-field and Morris water maze tests were performed on postnatal day 28 and day 60. The levels of lipid peroxidation products and antioxidant indices in the rat hippocampus were also detected. Pups from the MC-LR-treated groups had significantly lower scores than controls in the cliff avoidance test (p < 0.05). Cognitive impairment, malondialdehyde level, and total superoxide dismutase activity significantly increased in MC-LR-exposed pups compared with controls (p < 0.05). Therefore, the present study reveals that maternal exposure to MC-LR has adverse effects on neurodevelopment in rat offspring.

Characterizing white matter changes in cigarette smokers via diffusion tensor imaging

BACKGROUND

Tobacco use remains the most preventable cause of death; however, its effects on the brain, and particularly white matter, remain elusive. Previous diffusion tensor imaging (DTI) studies have failed to yield consistent findings, with some reporting elevated measures of fractional anisotropy (FA) and others reporting lowered FA.

METHODS

In our study, we sought to elucidate the effects of tobacco on white matter by using enhanced imaging acquisition parameters and multiple analysis methods, including tract-based spatial statistics (TBSS) with crossing fiber measures and probabilistic tractography.

RESULTS

Our TBSS results revealed that chronic cigarette smokers have decreased FA in corpus callosum and bilateral anterior internal capsule, as well as specific reduced anisotropy in the two major fiber directions in a crossing fiber model. Further, our tractography results indicated that smokers have decreased FA in tracts projecting to the frontal cortex from (1) nucleus accumbens, (2) habenula, and (3) motor cortex. We also observed that smokers have greater disruptions in those regions when they had recently smoked compared to when they abstained from smoking for 24h. Our results also support previous evidence showing hemispheric asymmetry, with greater damage to the left side compared to the right.

CONCLUSIONS

These findings provide more conclusive evidence of white matter disruptions caused by nicotine use. By better understanding the neural disruptions correlating with cigarette smoking we can elucidate the addictive course and explore targeted treatment regimens for nicotine dependence.

Moderate maternal food restriction in mice impairs physical growth, behavior, and neurodevelopment of offspring

Intrauterine growth retardation (IUGR) occurs in 3% to 7% of all pregnancies. Recent human studies have indicated that neurodevelopmental disabilities, learning disorders, memory impairment, and mood disturbance are common in IUGR offspring. However, the interactions between IUGR and neurodevelopmental disorders are unclear because of the wide range of causes of IUGR, such as maternal malnutrition, placental insufficiency, pregnancy toxemia, and fetal malformations. Meanwhile, many studies have shown that moderate food restriction enhances spatial learning and improves mood disturbance in adult humans and animals. To date, the effects of maternal moderate food restriction on fetal brain remain largely unknown. In this study, we hypothesized that IUGR would be caused by even moderate food restriction in pregnant females and that the offspring would have neurodevelopmental disabilities. Mid-pregnant mice received moderate food restriction through the early lactation period. The offspring were tested for aspects of physical development, behavior, and neurodevelopment. The results showed that moderate maternal food restriction induced IUGR. Offspring had low birth weight and delayed development of physical and coordinated movement. Moreover, IUGR offspring exhibited mental disabilities such as anxiety and poor cognitive function. In particular, male offspring exhibited significantly impaired cognitive function at 3 weeks of age. These results suggested that a restricted maternal diet could be a risk factor for developmental disability in IUGR offspring and that male offspring might be especially susceptible.

Smokeless tobacco use in pregnancy: an integrative review of the literature

OBJECTIVES

To systematically critique and summarise the available evidence on the outcomes of smokeless tobacco use in pregnancy to inform the public health response.

METHODS

In March 2013, a search was conducted of observational studies where the exposure to smokeless tobacco during pregnancy and maternal, placental and/or neonatal outcomes was assessed. Two reviewers extracted data and completed quality assessment of the literature utilizing the Agency for Healthcare Research and Quality criteria (West et al. 2002).

RESULTS

The search resulted in 211 articles, 21 (10%) of which met the final criteria for integrative review. Ten (10) of the studies are from India, seven (7) from Sweden, two (2) from Alaska and one (1) each from South Africa and Pakistan.

CONCLUSIONS

Many studies lacked sufficient power to estimate precise risks. Most reports were hindered by imprecise measures of exposure and lack of confounding variable control. However, there were indications that maternal smokeless tobacco use increases rates of stillbirth, low birth weight and alters the male:female live birth ratio. Maternal smokeless tobacco use may not be safe for mother or foetus.

A tobacco extract containing alkaloids induces distinct effects compared to pure nicotine on dopamine release in the rat

It has been suggested that minor alkaloids in plants play a role in the biological and neuronal actions of nicotine. We hypothesized that these molecules modulate the effect of nicotine on the activity of central dopamine (DA) neurons, one of the main cellular targets in addiction to drugs. In this study the effect of a single intraperitoneal injection of either nicotine or an alkaloid extract of the tobacco plant (0.5 mg/kg) on the efflux of DA were investigated. DA was measured in vivo by intracerebral microdialysis in the nucleus accumbens and the striatum of freely-moving rats. Results show that nicotine enhanced accumbal and striatal DA extracellular levels (+47 and 20% above baseline, respectively). The extract also evoked a significant increase in DA extracellular levels in both regions (+33 and +38% above baseline). However, this effect was significantly higher compared to nicotine in the striatum only. In conclusion, the tobacco extract enhanced the neurochemical effect of nicotine alone in the striatum, a response that could underlie the higher propensity of developing addictive-like behavior using nicotine with tobacco alkaloids.

The development of sensorimotor reflexes in albino mice; albino rats and black-hooded rats

The present investigation aimed to show the differences in the development of sensorimotor reflexes and their relationship to the structural changes in spinal cord, cerebellum and cerebral cortex in three rodent species. The three species are albino rats (A-Rats), black-hooded rats (B-Rats) and albino mice. The development of selected reflexes was examined from day (D1) to D21. The structural changes were investigated at D7, D14, and D21. The following reflexes were analyzed: fore-limb/hind-limb grasp, surface body righting, fore-limb hopping, chin tactile placing, visual placing and body righting in the air. The developmental pattern of the reflexes was different in three rodent species. Although the black-hooded rats and albino rats belong to the same species, they are different in their appearance and developmental pattern. The development of external features and sensorimotor reflexes appeared earlier in mice than in A-Rats and B-Rats. At D7, differentiation of neurons was observed in the spinal cord while in cerebellum and cerebrum the neurons were found to be undifferentiated. At D14 and D21, the differentiated neurons were observed in spinal cord, cerebellum and cerebrum. Our data indicate that the developmental pattern of the reflexes in rodents may not be species specific but may be related to the animal strain.