Nicotine toxicity to the ultrastructure of the testis in rats

The protective effects of curcumin against cigarette smoke-induced toxicity: A comprehensive review

Cigarette smoking (CS) is a crucial modifiable risk of developing several human diseases and cancers. It causes lung, bladder, breast, and esophageal cancers, respiratory disorders, as well as cardiovascular and metabolic diseases. Because of these adverse health effects, continual efforts to decrease the prevalence and toxicity of CS are imperative. Until the past decades, the impacts of natural compounds have been under investigation on the harmful effects of CS. Turmeric (Curcuma longa), a rhizomatous herbaceous perennial plant that belongs to the Zingiberaceae family, is the main source of curcumin. This review is an attempt to find out the current knowledge on CS's harmful effects and protective potential of curcumin in the pulmonary, liver, brain, gastrointestinal, and testis organs. According to the present review, simultaneous consumption of curcumin and CS can attenuate CS toxicities including chronic obstructive pulmonary disease, gastrointestinal toxicity, metabolic diseases, testis injury, and neurotoxicity. Moreover, curcumin suppresses carcinogenesis in the skin, liver, lungs, breast, colon, and stomach. Curcumin mediates these protective effects through antioxidant, anti-inflammatory, anti-apoptotic, and anti-carcinogenicity properties.

Alleviation of nicotine-induced reproductive disorder, clastogenicity, and histopathological alterations by fenugreek saponin bulk and nanoparticles in male rats

Nicotine is the most abundant ingredient in cigarette smoking and has serious side effects on the lung, heart, reproductive system, and many other human organs. Saponins extracted from many plants exhibit multiple biological actions such as anti-cancer effects. Therefore, the possible protective effect of fenugreek saponin (FS) and nanofenugreek saponin (NFS) against nicotine-induced toxicity in male rats was investigated in this study. Animals were divided into a control group and the nicotine (1.5 mg/kg/day), FS (25, 50, and 100 mg/kg/day), or/and NFS (20, 40, and 80 mg/kg/day) administered groups. Micronucleus assay, histopathological, and sperm abnormality examinations as well as measurement of the acetylcholinesterase (AChE) gene expression were conducted. Our findings revealed that nicotine treatment induced significant increases in the incidence of micronucleus, sperm abnormalities, and expression levels of AChE in addition to inducing histopathological changes in rat testis. On the other hand, administration of FS or NFS with nicotine significantly decreased the incidence of micronuclei and the percentage of sperm abnormalities as well as the expression levels of AChE gene. Moreover, nicotine-induced histological alterations were reduced by given FS or NFS with nicotine. In conclusion, nicotine-induced sperm abnormalities, chromosomal damage, and histological injuries were mitigated by administration of FS or NFS with nicotine, and thus, FS and NFS could be used as ameliorating agents against nicotine toxicity.

Phytomedicinal therapeutics for male infertility: critical insights and scientific updates

Infertility is a significant cause of anxiety, depression, and social stigma among couples and families. In such cases, male reproductive factors contribute widely to the extent of 20-70%. Male infertility is a multifactorial disease with several complications contributing to its diagnosis. Although its management encompasses both modern and traditional medicine arenas, the first line of treatment, adopted by most males, focuses on the reasonably successful medicinal plant-based conventional therapies. Phyto-therapeutics, which relies on active ingredients from traditionally known herbs, influences sexual behavior and male fertility factors. The potency of these phyto-actives depends on their preparation methods and forms of consumption, including decoctions, extracts, semi-purified compounds, etc., as inferred from in vitro and in vivo (laboratory animal models and human) studies. The mechanisms of action therein involve the testosterone pathway for stimulation of spermatogenesis, reduction of oxidative stress, inhibition of inflammation, activation of signaling pathways in the testes [extracellular-regulated kinase (ERK)/protein kinase B(PKB)/transformation of growth factor-beta 1(TGF-β1)/nuclear factor kappa-light-chain-enhancer of activated B cells NF-kB signaling pathways] and mediation of sexual behavior. This review critically focuses on the medicinal plants and their potent actives, along with the biochemical and molecular mechanisms that modulate vital pathways associated with the successful management of male infertility. Such intrinsic knowledge will significantly further studies on medicinal plants that improve male reproductive health.

Effect of Nicotine on STAT1 Pathway and Oxidative Stress in Rat Lungs

Background

Tobacco use is responsible for millions of preventable deaths due to cancer. Nicotine, an alkaloid chemical found in tobacco was proved to cause chronic inflammation and oxidative stress. The transcription factor STAT1 induces the expression of many proinflammatory genes and has been suggested to be a target for anti-inflammatory therapeutics. The following study investigated the effect of Nicotine on STAT1 pathway and oxidative stress in rat lung tissue.

Methods

Thirty rats were divided into 3 groups; group I considered as control, group II; its rats were daily injected with Nicotine at a dose of 0.4 mg/100 gm body for 8 successive weeks and group III; its rats were daily injected with Nicotine as group II, but the injection was stopped for another 4 weeks. STAT1α protein was assessed by immunohistochemistry, COX-2 and iNOS genes expression were evaluated by real time PCR and thiobarbituric acid reactive substances (TBARS) and total thiols were measured using spectrophotometric methods in the lung tissues of the rats.

Results

The results of the study revealed that group II rats had the highest expression of STAT1α protein and COX-2 and iNOS genes and oxidative stress in their lung tissues. Nicotine cessation for 4 weeks caused a marked reduction in the expression of STAT1α protein, COX-2 and iNOS genes and oxidative stress.

Conclusion

Induction of STAT1 pathway and the increase in oxidative stress may be the mechanisms through which Nicotine may induce its harmful effects.

The amelioration of nicotine-induced reproductive impairment in male mouse by Sambucus ebulus L. fruit extract

Nicotine as a toxic agent in cigarette smoke impairs the reproductive system. Sambucus ebulus extract (SEE) is shown to have some beneficial effects such as antioxidant properties. The aim of this study was to evaluate the effects of SEE on the hormones of the pituitary-gonadal axis, lipid peroxidation index, antioxidant enzymes, spermatogenesis, and epididymal sperm parameters in male mice treated with nicotine. Adult male mice were divided into five groups; A: normal saline, B: 1 mg/kg nicotine, C: 1 mg/kg nicotine and 10 mg/kg SEE, D: 1 mg/kg nicotine and 50 mg/kg SEE, D: 1 mg/kg nicotine and 100 mg/kg SEE. Treatments lasted for 35 days. The spermicidal activity of SEE was tested in vitro. Sperm count, motility and morphology were assessed for fertility. Serum testosterone, prolactin and luteinizing hormone (LH) were measured, using ELISA. Serum malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD) activity were measured, using colorimetric assays. Spermatogenesis was evaluated by Johnsen’s score and morphometry in histological slides. SEE at different doses did not have any spermicidal activity. Sperm parameters were reduced in the nicotine-treated group, compared with controls (P<0.01). Nicotine reduced testosterone and LH levels (P<0.01) and increased prolactin (P<0.01). A hike in MDA and a reduction in SOD activity without change on CAT, were observed in the nicotine group. Nicotine caused hypospermatogenesis. SEE improved most of the above-mentioned parameters, especially in the doses of 50 and 100 mg/kg. Beneficial effects of SEE in the doses of 50 and 100 mg/kg on male reproduction impairment, induced by nicotine might be partly attributed to the reduction of oxidative stress and changes in the hormones of the pituitary-gonadal axis.

Ameliorative effect of fractionated low-dose gamma radiation in combination with ellagic acid on nicotine-induced hormonal changes and testicular toxicity in rats

Nicotine is an active pharmacological ingredient in cigarette smoke, which may negatively influence the male reproductive system and fertility. This study aims to investigate the effect of fractionated low-dose radiation (fractionated-LDR) and/or ellagic acid (EA) on nicotine-induced hormonal changes and testicular toxicity in rats. Nicotine was administrated orally (1 mg/kg) for 30 days, afterward, rats were treated with LDR (2 × 0.25 Gy/1-week interval), EA (10 mg/kg, 14 consecutive days p.o.), or a combination of both fractionated-LDR and EA. Rats were sacrificed 24 h after the last dose of treatment, then testes were dissected for histopathology examination, along with some biochemical parameters in serum and testicular tissue were evaluated. Nicotine-induced oxidative stress was evidenced by an increase in testicular thiobarbituric acid reactive substances (TBARS) and a decrease in reduced glutathione (GSH) content. Additionally, the activities of testicular androgenic enzymes were decreased, and the activity of serum lactate dehydrogenase (LDH) was significantly increased. The hormonal changes were verified by a noticeable reduction in follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone serum levels. Histological evaluation revealed that the testicular seminiferous tubules structure was distorted. On the contrary, fractionated-LDR plus EA attenuated the negative changes caused by nicotine observed through biochemical and histological findings. Accordingly, the exposure to fractionated-LDR combined with EA may be a promising candidate for treating hormonal changes and testicular toxicity caused by nicotine.

The Antioxidant, Anti-Inflammatory, Pathological, and Behavioural Effects of Medicago sativa L. (Alfalfa) Extract on Brain Injury Caused by Nicotine in Male Rats

Nicotine is one of the most important compounds in cigarette which can cause changes in the concentration of neurotransmitters and damage to the nervous system. The aim of this study was to investigate the effect of the hydroalcoholic extract of Medicago Sativa L. (alfalfa) on controlling nicotine-induced brain damage and anxiety behaviour in rats. Forty-two male Wistar rats were randomly divided into six equal groups and treated daily as follows: a control group, T1 and T2 groups where animals were subcutaneously injected 250 and 500 mg/kg alfalfa extract, respectively, T3 and T4 groups where animals were injected subcutaneously 0.2 mg/kg nicotine and 250 and 500 mg/kg alfalfa extract, and T5 group in which only nicotine at the dose of 0.2 mg/kg was injected. At the end of the period after weighing, the elevated plus-maze test was taken from the animals. Serum assay was conducted to measure TCA, IL-1, and TNFα, and half of the brain tissue was used to measure oxidative stress parameters (GPx, SOD, TAC, and MDA) and the other parts were used for histopathological studies. Body weight in the T5 group was significantly different from that of the other groups. The time and number of open arms reduced in the T5 group. The duration and number of times in the open arm significantly decreased in the treated groups in a dose-depended manner. Malondialdehyde concentration was the highest in the nicotine group and the lowest in T2. The concentration of GPx and SOD was significantly increased in the presence of alfalfa extract in nicotine groups. TNFα and IL-1 in the T5 group showed a significant increase compared to the other groups. Moreover, the number of neurons and the level of necrotic neurons and gliosis significantly decreased and increased in the nicotine group, respectively, while these histopathological damages improved by treatment with alfalfa extract in T3 and T4 groups. Alfalfa extract can have a significant dose-dependent therapeutic effect on inducing oxidative damage and inflammatory responses of nicotine in the brain and reducing anxiety behaviours.

Comparison of the deleterious effects of yaji and cadmium chloride on testicular physiomorphological and oxidative stress status: The gonadoprotective effects of an omega-3 fatty acid

Objective

This study investigated testicular oxidative stress status and physiomorphological function in Wistar rats fed with yaji and cadmium chloride (CdCl₂).

Methods

Sixty male albino Wistar rats (12 per group) were randomly assigned to five groups: group I (control), group II (300 mg/kg.bw of yaji), group III (500 mg/kg.bw of yaji), group IV (2.5 mg/kg.bw of CdCl₂), and group V (2.5 mg/kg.bw of yaji+4 mg/kg.bw omega-3). Each group was evenly subdivided into two subgroups and treatment was administered for 14 days and 42 days, respectively. Semen quality (sperm count, progressive motility, normal morphology, and gonadosomatic index), hormones (testosterone, follicle-stimulating hormone, and luteinizing hormone), testicular oxidative stress markers (superoxide dismutase, catalase, glutathione peroxidase, and malonaldehyde) and testicular histomorphological features were examined.

Results

Yaji caused significant (p< 0.05) dose- and duration-dependent reductions in semen quality, the gonadosomatic index, testosterone, follicle-stimulating hormone, and luteinizing hormone. Yaji also caused significant (p< 0.05) dose- and duration-dependent decreases in superoxide dismutase, catalase, and glutathione peroxidase activity, as well as increased testicular malonaldehyde levels. Yaji induced distortions in the testicular histological architecture. CdCl₂ damaged testicular function by significantly (p< 0.05) reducing semen quality, reproductive hormone levels, and oxidative stress markers in albino Wistar rats. CdCl₂ also altered the histology of the testis.

Conclusion

This study shows that yaji sauce has similar anti-fertility effects to those of CdCl₂, as it adversely interferes with male reproduction by impairing oxidative stress markers and the function and morphological features of the testis.

Effects of nicotine on porcine pre-pupertal sertoli cells: An in vitro study

Smoke components, such as nicotine and its major metabolites, cross the blood-testis barrier and are detectable in the seminal plasma of both active smokers and individuals exposed to cigarette smoke. In vivo studies in a rat model have further demonstrated that nicotine exposure reduces the weight of the testis, as well as the number of spermatocytes and spermatids, and affects the ultrastructure of Sertoli cells (SC) - which serve as sentinels of spermatogenesis - causing intense germ cell sloughing in the tubular lumen that compromises offspring fertility. This study sought to determine the effects of nicotine on the viability and function of purified pig pre-pubertal SC. Nicotine exposure reduced the mRNA expression and protein levels of anti-Mullerian hormone (AMH) and inhibin B and impaired FSH-r sensitivity via the downregulation of FSH-r and aromatase gene expression compared to untreated SC. Overall, our study suggests that nicotine can significantly alter extracellular matrix and tight junction protein gene expression (e.g., laminin, integrin, and occludin), thus compromising cross-talk between the interstitial and tubular compartments and enhancing blood-testis barrier (BTB) permeability via downregulation of the mitogen-activated protein kinase (MAPK) pathway. These findings further elucidate a potential mechanism of action underlying nicotine exposure's detrimental effects on SC function in vivo.

Evaluation of toxicity of aerosols from flavored e-liquids in Sprague-Dawley rats in a 90-day OECD inhalation study, complemented by transcriptomics analysis

The use of flavoring substances is an important element in the development of reduced-risk products for adult smokers to increase product acceptance and encourage switching from cigarettes. In a first step towards characterizing the sub-chronic inhalation toxicity of neat flavoring substances, a study was conducted using a mixture of the substances in a base solution of e-liquid, where the standard toxicological endpoints of the nebulized aerosols were supplemented with transcriptomics analysis. The flavor mixture was produced by grouping 178 flavors into 26 distinct chemical groups based on structural similarities and potential metabolic and biological effects. Flavoring substances predicted to show the highest toxicological effect from each group were selected as the flavor group representatives (FGR). Following Organization for Economic Cooperation and Development Testing Guideline 413, rats were exposed to three concentrations of the FGR mixture in an e-liquid composed of nicotine (23 µg/L), propylene glycol (1520 µg/L), and vegetable glycerin (1890 µg/L), while non-flavored and no-nicotine mixtures were included as references to identify potential additive or synergistic effects between nicotine and the flavoring substances. The results indicated that the inhalation of an e-liquid containing the mixture of FGRs caused very minimal local and systemic toxic effects. In particular, there were no remarkable clinical (in-life) observations in flavored e-liquid-exposed rats. The biological effects related to exposure to the mixture of neat FGRs were limited and mainly nicotine-mediated, including changes in hematological and blood chemistry parameters and organ weight. These results indicate no significant additive biological changes following inhalation exposure to the nebulized FGR mixture above the nicotine effects measured in this sub-chronic inhalation study. In a subsequent study, e-liquids with FGR mixtures will be aerosolized by thermal treatment and assessed for toxicity.

Assessment of the toxicity effects of nicotine on sperm and IVF and the potential protective role of silymarin—an experimental study in mice

Background

Male infertility is usually caused via the inability to produce adequate quantities of healthy and active sperms. Nicotine (NIC) is an alkaloid organic compound, predominantly found in the leaves of the tobacco plant. The major part of the nicotine is not ionized, so it can easily pass through cell membranes. Meanwhile, most of the disorders are caused by oxidative stress due to oxygen free radicals and other reactive species. Antioxidant supplements and antioxidant-rich foods can reduce induced oxidative stress without becoming destabilized themselves. This study aimed to examine spermato-protective potential of silymarin (SIL), on sperm and in vitro fertility (IVF) rate in nicotine-treated mice.

Results

Our results show a significant increase in the number of abnormal sperm morphology after nicotine exposure, when compared to control groups (p < 0.05). On the other hand, SIL had a significant effect on the sperm count at each of the treated doses. Further, in the mice that received nicotine plus silymarin, the viable sperm percentage and the progressive sperm motility were significant (p < 0.05). Also, a significant reduction in the number of two-cell embryos and blastocyst-derived embryo was seen with increment in the number of dead embryos in mice receiving nicotine alone (p < 0.05).

Conclusions

In conclusion, SIL could support prevention of the adverse reproductive effects of nicotine. Moreover, SIL200 mg/kg may be therefore considered as a spermato-protective agent in dietary and herbal supplements.

Antioxidant and anti-apoptotic effects of royal jelly against nicotine-induced testicular injury in mice

This study describes the effects of royal jelly (RJ) on testicular injury induced by nicotine (NIC) in mice. Thirty-six male BALB/c mice were randomly divided into six groups (n = 6). Group 1 received normal saline, group 2 received 100 mg/kgBW/day RJ, groups 3 and 4 received NIC at doses of 0.50 and 1.00 mg/kgBW/day, respectively, and groups 5 and 6 received NIC at doses of 0.50 and 1.00 mg/kg BW/day, respectively, plus RJ. Following 35 days, the serum level of testosterone, histopathological changes, germ cell apoptosis, proliferating cell nuclear antigen (PCNA), malondialdehyde (MDA) content, and antioxidant indexes including total antioxidant capacity (TAC) and catalase (CAT) activity were determined. In addition, the mitochondria-dependent apoptosis was investigated by assessing the Bcl-2, p53, and Caspase-3 mRNA levels expression by reverse transcription-PCR (RT-PCR). Compared to NIC receiving groups, the concomitant administration of RJ could protect the testosterone reduction and histological damages. After RJ treatment, the level of tissue MDA content decreased, while tissue TAC and CAT levels were remarkably increased compared to NIC-exposed groups. Remarkable higher TUNEL-positive germ cells and low PCNA index were observed in NIC receiving groups. Besides, the expression level of Bcl-2 was significantly higher and the p53 and Caspase-3 levels were significantly lower in the RJ co-administration groups than NIC-only receiving groups. Our results confirmed that RJ effectively protects the testis against NIC evoked damages by antioxidant and anti-apoptotic effects involving the up regulation of the antioxidant status, mitochondria-dependent apoptosis pathway prevention, and the proliferating activity improvement.

Substance Abuse and Male Hypogonadism

Progressive deterioration of male reproductive function is occurring in Western countries. Environmental factors and unhealthy lifestyles have been implicated in the decline of testosterone levels and sperm production observed in the last fifty years. Among unhealthy lifestyles, substance and drug abuse is a recognized cause of possible alterations of steroidogenesis and spermatogenesis. Alcohol, opioids and anabolic-androgenic steroids are capable to reduce testosterone production in male interfering with testicular and/or hypothalamic-pituitary function. Other substances such as nicotine, cannabis, and amphetamines alter spermatogenesis inducing oxidative stress and subsequent apoptosis in testicular tissue. Substance and drug abuse is a potentially reversible cause of hypogonadism, defined as the failure of the testis to produce physiological concentrations of testosterone and/or a normal number of spermatozoa. The identification of the abuse is important because the withdrawal of substance intake can reverse the clinical syndrome. This review summarizes the most important clinical and experimental evidence on the effect of substance abuse on testosterone and sperm production.

Ultrastructural Study of Rat Testis Following Conventional Phototherapy during Neonatal Period

Introduction

Phototherapy is the most common treatment for neonatal jaundice. This study sought to determine ultrastructural changes in testis, at different time-points, after 48 hours of conventional phototherapy was given to newborn rats.

Methods

Newborn male Wistar rats (n = 36) were divided into two groups as follows - group 1 (G1), control (without phototherapy) and group 2 (G2), exposure to conventional phototherapy for 48 h. Six animals from each group were sacrificed on postnatal days (PND) 70, 100 and 130. The testes were dissected out and processed for Transmission Electron Microscopy (TEM).

Results

TEM showed that G2 on PND 70 and 100 showed damaged organelles, including nuclei, mitochondria, endoplasmic reticulum, vacuoles and electron dense bodies in the testes. Seminiferous Tubule on PND130 showed lesser damage. On PND70 ST wall thickness (STWT) of G2 was significantly higher (P < 0.001) than G1 STWT of G2 was significantly lower than G1 on PND100 (P = 0.047) and on PND130 (P < 0.001). Mitochondrial diameter in spermatogonia was significantly higher in G2 on PND70 (P = 0.001), PND100 (P = 0.031) and PND130 (P = 0.028). Primary spermatocytes in G2 also had larger mitochondria on PND70 (P < 0.001), PND100 (P = 0.007) and PND130 (P = 0.008). Further, spermatids had larger mitochondria in G2 on PND70 (P < 0.001), PND100 (P = 0.044) and PND130 (P < 0.001).

Conclusion

Phototherapy causes degenerative changes in rat testis on PND70 and 100 that partially recover by PND 130.

Royal jelly protects male mice against nicotine-induced reproductive failure

This study evaluated the possible protective effect of royal jelly (RJ) on sperm parameters and sperm malondialdehyde (MDA) concentration and in vitro fertilizing potential in nicotine (NIC) exposed male mice. Thrtiy-six male BALB/c mice were randomly divided into six groups (n = 6). Group 1 received normal saline, group 2 received 100 mg kg-1 per day RJ, groups 3 and 4 received NIC at doses of 0.50 and 1.00 mg kg-1 per day, respectively and groups 5 and 6 received NIC at doses of 0.50 and 1.00 mg kg-1 per day, respectively plus RJ. Caudal epididymal sperm characteristics, lipid peroxidation and in vitro fertilizing capacity and embryo development were evaluated after 35 days. The NIC treatment caused a significant decrease in sperm motility and viability and fertilization rate along with poor blastocyst formation and increased sperm DNA damage and MDA levels. Moreover, the incidences of chromatin abnormality in spermatozoa were significantly higher in NIC-exposed mice than those of control. Nevertheless, RJ treatment improved sperm parameters and in vitro fertilization outcome as well as sperm lipid peroxidation level. Data from the current study suggest that RJ has a potential repro-protective action against NIC-induced sperm abnormalities and embryotoxicity in mice.

A 90-day OECD TG 413 rat inhalation study with systems toxicology endpoints demonstrates reduced exposure effects of the aerosol from the carbon heated tobacco product version 1.2 (CHTP1.2) compared with cigarette smoke. I. Inhalation exposure, clinical pathology and histopathology

Within the framework of a systems toxicology approach, the inhalation toxicity of aerosol from a novel tobacco-heating potentially modified risk tobacco product (MRTP), the carbon-heated tobacco product (CHTP) 1.2, was characterized and compared with that of mainstream smoke (CS) from the 3R4F reference cigarette in a 90-day nose-only rat inhalation study in general accordance with OECD TG 413. CHTP1.2 is a heat-not-burn product using a carbon heat source to produce an aerosol that contains nicotine and tobacco flavor. At equal or twice the nicotine concentration in the test atmospheres, inhalation of CHTP1.2 aerosol led to a significantly lower exposure to harmful constituents and induced less respiratory tract irritation, systemic, and pathological effects compared with CS. Nasal epithelial changes were less pronounced in the CHTP1.2- than in the CS-exposed groups and reverted in the nicotine concentration-matched group after a recovery period. Lung inflammation was minimal in the CHTP1.2-treated groups compared with the moderate extent seen in the 3R4F groups. Many other toxicological endpoints evaluated did not show CHTP1.2 aerosol exposure-related effects, and no effects not seen for 3R4F were observed. These observations were consistent with findings from previous studies in which rats were exposed to MRTP aerosols containing similar nicotine concentrations.

Low-dose Nicotine Exposure Induced the Oxidative Damage of Reproductive Organs and Altered the Sperm Characteristics of Adolescent Male Rats

Background

Nicotine is a major toxic and hazardous component of cigarette smoke, and it has been widely used in nicotine replacement therapy (NRT). This study was aimed to investigate the effects of chronic low-dose nicotine on sperm characteristics and reproductive organ integrity in adolescent male Sprague-Dawley rats.

Methods

Twelve rats were equally divided into two groups. Group I received normal saline, and group II received 0.6 mg/kg body weight nicotine intraperitoneally for 28 consecutive days. At the end of the experimental period, sperm was collected for sperm characteristic evaluation, and the testes and prostate were isolated for biochemical and morphological analysis. The effects of nicotine on the body and reproductive organ weights of the animals were evaluated.

Results

Chronic nicotine treatment significantly (P < 0.05) altered the sperm count, motility, viability, and morphology, and remarkably increased the malondialdehyde (P < 0.001) and advanced oxidation protein product (P < 0.05) levels in the testes and prostate of nicotine-treated group compared to control group. Moreover, nicotine caused a significant decrease (P < 0.05) in the superoxide dismutase activity of the testes. No significant differences were observed in the reduced glutathione level in both of the testes and prostate of nicotine group compared with control group. Nicotine also induced histopathological alteration in the testes.

Conclusion

A low-dose nicotine exposure at 0.6 mg/kg caused detrimental effects on sperm characteristics and induced oxidative stress in the testes and prostate.

Testicular cells exhibit similar molecular responses to cigarette smoke condensate ex vivo and in vivo

Male exposure to cigarette smoke is associated with seminal defects and with congenital anomalies and childhood cancers in offspring. In mice, paternal exposure to cigarette smoke condensate (CSC) causes molecular defects in germ cells and phenotypic effects in their offspring. Here we used an ex vivo testicular explant model and in vivo exposure to determine the concentration at which CSC impairs spermatogenesis and offspring development. We explanted testis tissue at postnatal day (P)5.5 and cultured it until P11.5. Assessment of growth parameters by analyzing expression of cell-specific markers revealed that the explant system maintained structural and functional integrity. We exposed the P5.5 to -11.5 explants to various concentrations (40-160 µg/ml) of CSC and confirmed that nicotine in the CSC was metabolized to cotinine. We assessed various growth and differentiation parameters, as well as testosterone production, and observed that many spermatogenesis features were impaired at 160 µg/ml CSC. The same parameters were impaired by a similar CSC concentration in vivo Finally, females mated to males that were exposed to 160 µg/ml CSC neonatally had increased rates of pup resorption. We conclude that male exposure to CSC impairs offspring development and that the concentration at which CSC impairs spermatogenesis is similar in vivo and ex vivo. Given that the concentrations of CSC we used contained similar doses of nicotine as human smokers are exposed to, we argue that our model mimics human male reproductive effects of smoking.-Esakky, P., Hansen, D. A., Drury, A. M., Felder, P., Cusumano, A., Moley, K. H. Testicular cells exhibit similar molecular responses to cigarette smoke condensate ex vivo and in vivo.

Ameliorating effects of curcumin on nicotine-induced mice testes

BACKGROUND/AIM

The aim of this study was to determine the antioxidative effect of curcumin on nicotine-induced mice testis.

MATERIALS AND METHODS

Sixty Swiss albino male mice were divided into five groups, each containing 12 mice. The first group was used as a control. To induce toxicity in the second and third group, nicotine (0.4 mg/kg/day) was injected intraperitoneally into mice for 14 and 28 days, respectively. The mice in the fourth and fifth group were injected with nicotine (0.4 mg/kg/day) and orally treated with curcumin (200 mg/kg) for 14 and 28 days, respectively. Testosterone levels were measured from blood samples and testis tissues were examined under light and electron microscopes.

RESULTS

Light and electron microscopic examinations of the nicotine-induced groups showed evident degenerations in spermatogenic cells, Sertoli cells, and Leydig cells. The groups treated with curcumin had less testicular alterations. The mice that were sacrificed after 28 days in the groups treated with curcumin showed minor degenerations. Furthermore, the median levels of testosterone significantly decreased in the nicotine-induced groups in comparison with those in the control group.

CONCLUSION

The results indicated that curcumin might be a potential therapeutic agent for testicular injury caused by nicotine addiction.

Prenatal and lactation nicotine exposure affects Sertoli cell and gonadotropin levels in rats

Nicotine is largely consumed in the world as a component of cigarettes. It can cross the placenta and reach the milk of smoking mothers. This drug induces apoptosis, affects sex hormone secretion, and leads to male infertility. To investigate the exposure to nicotine during the whole intrauterine and lactation phases in Sertoli cells, pregnant rats received nicotine (2 mg/kg per day) through osmotic minipumps. Male offsprings (30, 60, and 90 days old) had blood collected for hormonal analysis (FSH and LH) and their testes submitted for histophatological study, analysis of the frequency of the stages of seminiferous epithelium cycle, immunolabeling of apoptotic epithelial cells (TUNEL and Fas/FasL), analysis of the function and structure of Sertoli cells (respectively using transferrin and vimentin immunolabeling), and analysis of Sertoli-germ cell junctional molecule (β-catenin immunolabeling). The exposure to nicotine increased the FSH and LH plasmatic levels in adult rats. Although nicotine had not changed the number of apoptotic cells, neither in Fas nor FasL expression, it provoked an intense sloughing of epithelial cells and also altered the frequency of some stages of the seminiferous epithelium cycle. Transferrin and β-catenin expressions were not changed, but vimentin was significantly reduced in the early stages of the seminiferous cycle of the nicotine-exposed adult rats. Thus, we concluded that nicotine exposure during all gestational and lactation periods affects the structure of Sertoli cells by events causing intense germ cell sloughing observed in the tubular lumen and can compromise the fertility of the offspring.

N (G)-nitro-L-arginine Methyl Ester Protects Against Hormonal Imbalances Associated with Nicotine Administration in Male Rats

Background:

The administration of nicotine is associated with altered hormonal imbalances and increased serum and testicular nitric oxide (NO) level.

Aim:

This study sought to investigate the effects of NO inhibition with N^G-nitro-L-arginine methyl ester (L-NAME) on altered hormonal imbalance in adult male albinorats.

Materials and Methods:

Rats were administered with 0.5 mg/kg body weight (BW) and 1.0 mg/kg BW nicotine and were treated with L-NAME in the drinking water or drinking water alone for 30 days. Serum was analyzed for testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), and prolactin using radioimmunoassay.

Results:

Nicotine administration significantly decreased (P < 0.05) testosterone in the low and high dose treated groups and FSH in the high dose treated group when compared with the control group. There was a significant increase (P < 0.05) in mean LH and prolactin level in the high dose treated group when compared with the control. Concomitant treatment with nicotine and L-NAME produced significant increases in testosterone and FSH, and a decrease in prolactin in 1.0 mg/kg BW. L-NAME alone did not lead to a significant increase in testosterone when compared with control.

Conclusion:

These data demonstrate that the suppressive effects of nicotine on testosterone level of the adult male rat can be prevented by NOS blockade with L-NAME. It appears that these beneficial effects are mediated primarily within the gonad; however, the involvement of the pituitary cannot be totally ruled out.

Effects of nicotine on the testicular toxicity of streptozotocin-induced diabetic rat

The aim of the present study is to investigate whether nicotine augmented the testicular toxicity and angiotensin converting enzyme inhibitor, enalapril, can ameliorate the effects in diabetic rat. Male Sprague Dawley rats were randomized into five groups: control, nicotine, diabetic, Diab + Nico, and Diab + Nico + Enal. Animals were made diabetic by single injection of streptozotocin (55 mg/kg/intraperitoneally). Nicotine dissolved in drinking water at a concentration of 100 µg/ml was given ad libitum and enalapril was given orally at a dose of 10 mg/kg/day for four consecutive weeks. After 4 weeks of treatment, animals were killed and biochemical parameters glucose, glycosylated hemoglobin, cotinine, and the testosterone levels were measured. Testicular toxicity was evaluated using sperm count, sperm comet assay, histology, and immunohistochemical staining of 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxo-dG) and the proinflammatory markers (nuclear factor kappa B (NF-κB), cyclooxygenase (COX-2), and tissue necrotic factor alpha (TNF-α)) evaluated by western blotting. Results showed that nicotine did not alter the blood glucose and glycosylated hemoglobin level, significantly decreased the sperm count and increased the sperm DNA damage. These changes were accompanied by significant increases in the 8-oxo-dG, NF-κB, COX-2, and TNF-α expression. Furthermore, the intervention of enalapril in nicotine-treated diabetic rat attenuated the testicular damage and restored sperm count, sperm DNA damage, as well as reduced the expression of NF-κB, COX-2, and TNF-α. These findings clearly suggest that nicotine not only augmented the testicular toxicity in the diabetic rat but also increases the risk of germ cell toxicity effects that were attenuated by enalapril treatment.

Effects of Nigella sativa (Habbatus sauda) Oil and Nicotine Chronic Treatments on Sperm Parameters and Testis Histological Features of Rats

Twenty-four Sprague-Dawley male rats (7-9 weeks old, 200-250 g) were divided into Nicotine (N) (0.5 mg/100 g body weight (BW), Nicotine Control (NC) (saline, 0.1 mL/100 g BW), Habbatus sauda oil (HS) (6.0  μ L/100 g BW), and Habbatus sauda Control (HSC) (corn oil, 0.1 mL/100 g BW) groups and treated for 100 days. Sperm parameters and seminiferous tubules measurements were evaluated. The N showed a significantly lower sperm motility (1.03 ± 0.05 × 10(6) sperm/mL) and percentage of normal (82.61 ± 0.03%) and live (93.88 ± 0.01%) sperm, higher value for the seminiferous tubule (253.36 ± 1.83  μ m) and lumen (100.15 ± 2.38  μ m) diameters and spermatogonia (19.85 ± 0.39  μ m) and spermatocytes (33.37 ± 0.59  μ m) layers, and thinner spermatid-sperm layer (22.14 ± 0.71  μ m) than the NC (P < 0.05). The HS had significantly higher sperm motility (1.49 ± 0.04 × 10(6) sperm/mL) and percentage of normal (90.61 ± 0.01%) and live (96.98 ± 0.01%) sperm, smaller lumen diameter (67.53 ± 2.34  μ m) and thinner spermatogonia (17.67 ± 0.32  μ m) and wider spermatid-sperm (36.95 ± 0.79  μ m) layers than the HSC (P < 0.05). This research confirmed that nicotine reduced sperm motility and morphology of normal and live sperms and also affected the testis histology, while Habbatus sauda oil increased sperm quality and gave better testis histological features.

Prevalence of abnormal spermatozoa in tobacco chewing sub-fertile males

AIM

The aim of the following study is to find out the prevalence of abnormal spermatozoa and associated functional parameters in clinical semen samples of sub-fertile males with the tobacco chewing habit.

SETTINGS AND DESIGN

Retrospective study was conducted at infertility unit of a tertiary health care center, in a period of 3 years.

MATERIALS AND METHOD

Semen of 642 males were analyzed; of them 194 men (30.2%) were tobacco chewers and they were grouped according to their intensity of chewing (<10 and ≥ 10 packets/day). Counts, motility, vitality, and morphology of sperms were analyzed.

RESULTS

In tobacco chewers, 66% of subjects were oligozoospermic, 85% asthenozoospermic and 28% teratozoospermic. Sperm counts (odds ratio [OR] =2.2; 95% confidence interval [CI]: 1.5-3.09), motility (OR = 3.2; 95% CI: 2.05-4.9), and normal morphology (OR = 8.4; 95% CI: 4.9-14.6) were significantly affected (P = 0.001) in tobacco chewers than the non-chewing group. Further, in comparison to the intensity of tobacco chewing, patients with the intensive practice of using ≥10 packets/day had a significant effect on sperm morphology (P = 0.003, OR = 2.7; 95% CI = 1.41-5.08) only. Structural defects in head (P = 0.001) and cytoplasmic residues (P = 0.001) were found to be positively correlated with the intensive chewing, but no significant changes were found in anomalies in mid-piece and tail.

CONCLUSION

The adverse impact of tobacco chewing on semen parameters was evident even with mild chewers, but with the intensive chewing practice, phenotypes of sperms, mainly defects in the head and cytoplasmic residue were severely affected.

Long-term treatment of hydrogen-rich saline abates testicular oxidative stress induced by nicotine in mice

PURPOSE

The present study was designed to test the hypothesis that long-term treatment with hydrogen-rich saline abated testicular oxidative stress induced by nicotine in mice.

METHODS

The effects of hydrogen-rich saline (6 ml/kg, i.p.), vitamin C (60 mg/kg, i.p.) and vitamin E (100 mg/kg, i.p.) on reproductive system and testicular oxidative levels in nicotine-treated (4.5 mg/kg, s.b.) mice were investigated.

RESULTS

It was found that vitamin C and vitamin E attenuated serum oxidative level, but did not lower testicular oxidative levels in mice subjected to chronic nicotine treatment, and did not improve the male reproductive damage and apoptosis induced by nicotine. Different from normal antioxidants, vitamin C and vitamin E, hydrogen-rich saline abated oxidative stress in testis, and protected against nicotine-induced male reproductive damages.

CONCLUSION

Our results first demonstrated that long-term treatment with hydrogen-rich saline attenuated testicular oxidative level and improved male reproductive function in nicotine-treated mice.

The effect of long term nicotine exposure on nicotine addiction and fetal growth

OBJECTIVE

To investigate the effect of nicotine exposure starting before coitus and continuing during pregnancy and lactation period on delivery rate, fetal growth and nicotine addiction in rats.

MATERIAL AND METHODS

Ten female Swiss Albino rats were divided into 2 groups as the nicotine group (NG) (n=5), and the control group (n=5), conceived by adding 2 male rats to each group. While the control group was given only normal drinking water, 0.4 mg/kg body weight (BW)/day nicotine was given to the NG in drinking water. After delivery, the BWs of pups were recorded weekly for 6 weeks and their drinking water preferences were assessed. Meanwhile, pups of the NG continued to receive 0.4 mg/kg/day nicotine for 12 months while the controls continued with normal drinking water.

RESULTS

At the end of the 6(th) week, it was determined that 30 (69%) rats out of 43 in the NG and only 7 rats (20%) out of 35 in the control group preferred the nicotine added drinking water (p<0.05). No significant difference was observed between control and NGs in post-natal birth weights and BWs recorded for 6 weeks. On the contrary, a significant decrease (p< 0.05) was observed in the BWs of NG at the end of 12 months nicotine exposure.

CONCLUSION

Use of maternal nicotine in pregnancy and lactation periods, even at a low dose, may be effective in nicotine addiction development although it may not affect delivery rate, and BWs of pups after delivery and during six weeks follow up in the lactation period.

Testicular toxicity and sperm quality following cadmium exposure in rats: Ameliorative potentials of Allium cepa

AIMS:

This study was carried out to investigate the effect of Allium cepa crude extract on cadmium-induced testicular toxicity in rats.

MATERIALS AND METHODS:

Adult male Sprague-Dawley rats were randomized into 4 groups (n = 6). Group 1 was used as control, group 2 was administered 0.3 mg/kgBW of cadmium sulfate (CdSO₄) intraperitoneally for 3 days, group 3 was pretreated with 1 ml/100 g BW of Allium cepa (AcE) for 8 weeks followed by intraperitoneal administration of 0.3 mg/kgBW of CdSO₄ in the last 3 days of experiment, and group 4 was administered 1 ml/100 g BW of AcE throughout the experiment. Testicular weight and semen analysis revealing the sperm count, sperm motility, and sperm morphology was carried out. Superoxide dismutase (SOD), catalase activities, and lipid peroxidation status were also carried out in testes.

RESULTS:

The study demonstrated that Allium cepa ameliorated CdSO₄–induced alteration in testicular weight, sperm count, sperm motility, and sperm morphology. It also showed that Allium cepa attenuated the derangement of lipid peroxidation profile in testicular tissues caused by CdSO₄ exposure.

CONCLUSIONS:

The findings in the study showed that pre-treatment of rat model with Allium cepa extract prevented CdSO₄–induced reproductive toxicity by improving sperm quality and enhancing testicular lipid peroxidation status.

Toxicology of smokeless tobacco: implications for immune, reproductive, and cardiovascular systems

The popularity of smokeless tobacco (ST), or noncombusted tobacco, usually placed within the mouth to be chewed, sucked, or swallowed, is growing rapidly and its prevalence of use is rising globally, due (in part) to greater convenience, as allowable cigarette smoking areas are rapidly decreasing, and increased social acceptability. Though data are limited, ST usage has been directly linked to a number of adverse health outcomes. The potential role that immune dysfunction, including dysregulation of immune cells and their components, may play in the progression of these adverse health outcomes is only just beginning to emerge. Evidence suggesting reproductive outcomes, such as perinatal mortality, preterm birth, and reduced sperm viability, also exists in conjunction with ST use. Cardiovascular health may also be impacted by ST use, resulting in increased blood pressure and endothelial dysfunction, both of which may potentially lead to cardiovascular diseases. This review describes the toxicological implications associated with ST use, with emphasis on immune, reproductive, and cardiovascular outcomes. Epidemiological studies are discussed with respect to experimental studies to help develop the relationship between ST and disease pathology. This review also summarizes the gaps in ST knowledge and potential future directions that are needed to more fully delineate the complex systems driving the adverse health outcomes associated with its use.

Effect of nicotine on spermatogenesis in adult albino rats

This study aimed to assess the effects of nicotine on spermatogenesis in 140 mature male albino rats divided into group A (controls), group B (sham controls), group C (nicotine treated) and group D (nicotine withdrawal). Group C was subdivided into CI, CII, CIII according to the dose of injected nicotine (0.2, 0.4 and 0.6 mg nicotine per 100 g per day), where each subgroup was further subdivided according to the treatment duration into subgroups a, b and c that received nicotine for 2, 4 and 8 weeks. Group D received nicotine for 8 weeks followed by withdrawal for another 8 weeks to assess testicular recovery. Testicular tissue sections were subjected to haematoxylin and eosin, Masson's trichrome stains and morphometry. The results showed that nicotine caused degenerative changes in the seminiferous tubules, revealed by altered general tubular architecture, decreased thickness of the spermatogenic cell masses, Sertoli cell vacuolation and thickened basal lamina. These changes were proportional to the nicotine dose and duration. Following nicotine withdrawal, regeneration of the damaged seminiferous tubules was observed to be rather complete in CI group. It is concluded that nicotine could adversely affect testicular spermatogenesis in a dose- and time-dependent manner which would be almost reversible after nicotine withdrawal, especially after small doses.

Significant modulation of mitochondrial electron transport system by nicotine in various rat brain regions

The mitochondrion is the organelle responsible for generation of most usable energy in a cell. It also plays an important role in a series of physiological processes such as apoptosis and proliferation. Although previous studies have demonstrated that nicotine modulates the morphology and function of mitochondria, the mechanism(s) underlying these effects is largely unknown. In this study, using a microarray consisting of 4793 clones derived from a mouse dopamine cDNA library, we profiled the gene expression patterns for six brain regions (amygdala, hippocampus, nucleus accumbens, prefrontal cortex, striatum and ventral tegmental area) of female Sprague-Dawley rats subjected to nicotine treatment for 7days through osmotic minipump infusion. We identified a number of genes and pathways, including components of the electron transport system of mitochondria, such as cytochrome c oxidase subunit I (Mt-co1), Mt-co2, Mt-co3, cytochrome b (Mt-cyb), mitochondrial NADH dehydrogenase 4 (Mt-nd4), and Mt-nd6, that were significantly modulated by nicotine in multiple brain regions. Bioinformatics analysis provided evidence that Gene Ontology categories related to the electron transport system were overrepresented in each brain region. Finally, the results from the microarray analysis were verified by quantitative RT-PCR for four representative genes. Together, our findings imply that mitochondria are involved in neuronal adaptation to chronic nicotine exposure.

Cigarette smoke decreases mitochondrial porin expression and steroidogenesis

Steroidogenic acute regulatory protein (StAR) facilitates the movement of cholesterol from the outer to inner mitochondrial membrane for steroidogenesis. Here, we investigated the effect of cigarette smoke (CS) on steroidogenesis using adrenal mitochondria isolated from mice chronically exposed to CS. Steroidogenesis was decreased approximately 78% in CS-exposed mitochondria, as measured by synthesis of the steroid hormone precursor pregnenolone. This effect was accompanied by decreased mitochondrial import of (35)S-StAR. Further characterization of the imported (35)S-StAR by native gradient PAGE revealed the presence of a high molecular weight complex in both control and CS-exposed groups. Following density gradient fractionation of (35)S-StAR that had been extracted from control mitochondria, precursor StAR could be found in fractions 2-6 and smaller-sized StAR complexes in fractions 6-13. In the CS-exposed group, the appearance of precursor shifted from fraction 1-6 and the smaller complexes in fractions 6-9 disappeared. Mass spectrometric analysis revealed that the (35)S-StAR-associated protein complex was composed of several resident matrix proteins as well as the OMM resident, VDAC. VDAC expression was greatly reduced by CS, and blockage of VDAC with Koenig's polyanion decreased pregnenolone synthesis in isolated mitochondria. Taken together, these results suggest that VDAC may participate in steroidogenesis by promoting StAR interaction with the OMM and that CS may inhibit steroidogenesis by reducing VDAC-StAR interactions.

Molecular mechanism of reduction in pregnenolone synthesis by cigarette smoke

Steroidogenic acute regulatory protein (StAR) facilitates the movement of cholesterol from the outer to inner mitochondrial membrane for the synthesis of pregnenolone. Here, we investigated the molecular mechanism of the reduction of pregnenolone synthesis by cigarette smoke condensate (CSC). Pre-exposure or post-exposure of cells with CSC led to reduced pregnenolone synthesis, in a fashion similar to its effect on isolated mitochondria. However, there was no difference in the expression of 30 kDa StAR in cells treated with moderately concentrated CSC by either regimen. The active form of 37 kDa StAR is degraded easily suggesting that the continuous presence of CSC reduces StAR expression. Mitochondrial import of (35)S-methionine-labeled StAR followed by extraction of the StAR-mitochondrial complex with 1% digitonin showed similarly sized complexes in the CSC-treated and untreated mitochondria. Further analysis by sucrose density gradient centrifugation showed a specific complex, "complex 2", in the untreated mitochondria but absent in the CSC-treated mitochondria. Mass spectrometric analysis revealed that complex 2 is the outer mitochondrial protein, VDAC1. Knockdown of VDAC1 expression by siRNA followed by co-transfection with StAR resulted in a lack of pregnenolone synthesis and 37 kDa StAR expression with reduced expression of the intermediate, 32 kDa StAR. Taken together, these results suggest that in the absence of VDAC1, active StAR expression is reduced indicating that VDAC1 expression is essential for StAR activity. In the absence of VDAC1-StAR interaction, cholesterol cannot be transported into mitochondria; thus the interaction with VDAC1 is a mandatory step for initiating steroidogenesis.

Morphometric and morphological features of the ventral prostate in rats submitted to chronic nicotine and alcohol treatment

Clinical studies analyzing simultaneous nicotine-alcohol use by patients showed important alterations in various organic systems such as: respiratory, digestory, and genital. Also, the prostatic morphology and physiology have been analyzed, specially due to large occurrence of prostatic diseases. Then, this work aimed at determining the structure and ultrastructure of the prostatic stroma and epithelium, as well as the stroma epithelium interactions from rats submitted to simultaneous long-term alcohol-nicotine treatment. A total of 40 male rats were divided into four groups: control group (10 animals) received tap water; alcoholic group (10 animals) received diluted 10% Gay Lussac ethanol; nicotine group (10 animals) received a 0.125mg/100g of body weight dose of nicotine injected subcutaneosly on a daily basis; nicotine-alcohol group (10 animals) received simultaneous alcohol and nicotine treatment. After 90 days of treatment, the animals were sacrificed and samples from the ventral lobe of the prostate were collected and processed for transmission electron and light microscopies. The results showed atrophied epithelium; prostatic intra-epithelial neoplasia; dilated cisterns of the granular endoplasmic reticulum, large amounts of collagen fibers besides inflammatory cells, specially in the alcoholic and nicotine-alcohol groups. Therefore, it could be concluded that the association between alcohol and nicotine caused the impairment of the prostatic secretory process. Moreover, this association is related to prostatic pathogenesis, which could lead to late glandular malignancy.

Morphometric and ultrastructure features of the ventral prostate of rats (Rattus norvegicus) submitted to long-term nicotine treatment

The harmful effects of nicotine on male genital system fertility have been reported in experimental and clinical studies. However, its effects on prostatic cells and glandular pathogenesis remain unclear. The aim of the present study was to analyse the histological, histochemical and ultrastructural alterations, in addition to stereology, of the ventral lobe of the prostate of rats, submitted to chronic nicotine administration, as well as to establish the relationship between these changes and prostate diseases. Twelve male Wistar rats (Rattus norvegicus) were divided into two experimental groups: group I (nicotine) and group II (control). Samples of the ventral prostate were collected, processed and submitted to histological analysis, acid phosphatase histochemistry and ultrastructural analysis by transmission and scanning electron microscopies. The results showed that in the nicotine group, the secretory epithelial cells of the ventral lobe of the prostate were atrophied, and prostatic intraepithelial neoplasia occurred and reduced the expression of acid phosphatase. The disorganisation of organelles involved in the glandular secretory process, accompanied by biomembrane destructuring, was also observed. In conclusion, nicotine causes drastic alterations in the secretory epithelium of the ventral prostate, compromising its function. Furthermore, nicotine also induces premalignant lesions in the prostate gland, thus representing a risk factor in the development of prostate diseases.

Relationship between semen quality and tobacco chewing in men undergoing infertility evaluation

OBJECTIVE

Male fertility is affected by a variety of lifestyle habits that include tobacco use. A large population of Indian men is addicted to tobacco chewing. The objective of our study was to assess the relationship between tobacco chewing in these Indian men--who were part of an infertile couple--and their sperm characteristics.

DESIGN

Retrospective study.

SETTING

Private infertility clinic.

PATIENT(S)

Six hundred thirty-eight male patients undergoing infertility evaluations were grouped according to the frequency of their tobacco chewing habit: mild (< 3 times/day, n = 177), moderate (3-6 times/day, n = 264), and severe (> 6 times/day, n = 197).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Sperm characteristics (concentration, motility, morphology, and viability).

RESULT(S)

Sperm concentration, percentage motility, morphology, and percentage viability were significantly higher in the mild group vs. the moderate group and in the moderate group vs. the severe group. The percentage of men with azoospermia rose with the level of addiction (1%, 3%, and 14%) as did the percentage of men with oligoasthenoteratozoospermia (2%, 8%, and 29%), although the differences were not statistically significant.

CONCLUSION(S)

In our study, use of chewing tobacco by a group of Indian men who were undergoing infertility evaluation was strongly associated with a decrease in sperm quality and to a lesser extent with oligoasthenozoospermia or azoospermia. Infertile men should be counseled about the adverse effects of tobacco chewing on sperm quality.

Effect of nicotine exposure during gestation on neonatal rat crystalline lenses

PURPOSE

To assess histologically the influence of maternal nicotine exposure during gestation in vivo on crystalline lenses in neonatal rats using different dosages of the test compound simulating the range of low, moderate, and heavy smokers in humans.

METHODS

Experimentally naive, adult female Wistar-albino rats (200-250 g) were mated with adult male rats over 2 days for copulation in the proportion of two females for every male animal. After confirming pregnancy with vaginal smear method, 40 gravid rats (dams) were then randomly assigned into four equal groups (three experimental and one control; n=10 in each). Groups 1, 2, and 3 experimental dams were treated with intraperitoneal (i.p.) (-)-nicotine tartrate at doses of 0.5, 1, and 2 mg/kg body weight/day, respectively, during pregnancy from gestational days 9 through 21. Group 4 control dams were given i.p. saline solution daily for the same period. After normal delivery, the eyes were removed at postnatal day 1 or day 30 for macroscopic and histopathologic investigation of the lenses.

RESULTS

Control and group 1 litters had normal anterior lens capsules with a single layer of anterior cuboidal epithelial cells, regularly orientated cortical and nuclear lens fibres, and a clear posterior lens capsule with no lining epithelial cells behind the equator. On the other hand, some lenses in groups 2 and 3 litters had mature or immature cataract macroscopically at postnatal 30th day. Histopathologic findings suggesting cataractogenesis included cortical lens fibre cell swelling and liquefaction, prominent epithelial cells lining the posterior lens capsule behind the equator, and the retention of lens nuclei into the deeper and central area. Moreover, some lenses were immature developmentally, indicating arrested lenticular embryogenesis at vesicle stage.

CONCLUSIONS

Nicotine exposure during pregnancy has teratogenic and cataractogenic effects on developing crystalline lenses in neonatal rats both macroscopically and histopathologically. If appropriate dose of nicotine can be identified, nicotine-induced cataract formation may possibly be used as a new experimental cataract model in animal studies. Therefore, future studies are needed in this respect. Eye (2004) 18, 67-73. doi:10.1038/sj.eye.6700511

Effect of gestational nicotine treatment on newborn rat retina: a histopathological and morphometric analysis

BACKGROUND

Smoking is a significant risk factor in several debilitating and fatal diseases. It has been implicated in bilateral tobacco-toxic and Leber's hereditary optic neuropathies. Although it has been demonstrated that smoking has a cumulative effect on retinal and optic nerve functions and causes diffuse and localised retinal sensitivity decrease in healthy chronic heavy smokers, the affected retinal layer has not been identified and there is no experimental study investigating the effect of nicotine exposure during gestation on the newborn rat retina.

PURPOSE

This experimental investigation evaluated histologically the influence in vivo of maternal nicotine treatment during pregnancy on the newborn rat retina. Different dosages of the test compound simulated the range of low, moderate, and heavy smokers in humans.

METHODS

Experimentally naive, adult female Wistar-albino rats weighing 200-250 g were mated with adult male rats over 2 days for copulation in the proportion of two females for every male animal. After confirming pregnancy with vaginal smear method, 40 gravid rats (dams) were then randomly assigned into four equal groups (three experimental and one control; n = 10 in each). On day 9 of gestation, groups 1, 2, and 3 experimental dams were treated with intraperitoneal (i.p.) (-)-nicotine tartrate at doses of 0.5, 1, and 2 mg kg body weight-1 day-1, respectively during pregnancy from gestational day 9-21. Group 4 control dams were given i.p. saline solution daily for the same period. After normal delivery, the newborn litters were sacrificed at postnatal day 1 or day 30. The eyes were enucleated for histopathologic and morphometric analysis of the retinas. Nicotine-induced neuronal changes were measured by morphometric analyses on cell counts of ganglion cell layer (linear cell density in number per unit length of retina) and thickness of the various retinal layers.

RESULTS

The litters in control group 4, and experimental groups 1 and 2 had normal retinal findings. On the other hand, morphometric analysis of retinal sections in experimental group 3 eyes demonstrated a 20.7% decrease in the number of surviving ganglion cells (40.7 +/- 2.0) compared with controls (51.3 +/- 1.1; p < 0.001). The thickness of whole retina (126.6 +/- 5.4 microm) was also reduced by 13.5% compared with controls (146.3 +/- 4.5 microm; p = 0.007). The main site of retinal atrophy was the inner plexiform layer (30.1 +/- 1.6 microm vs 43.5 +/- 1.3 microm; p < 0.001) with almost no change in the other retinal layers.

CONCLUSIONS

Gestational nicotine treatment induces marked changes in the organisation of the developing retina in newborn rats histopathologically. Quantitative morphometric analysis clearly demonstrated that the two most affected structures were the retinal ganglion cells and the inner plexiform layer, both of which are supplied by central retinal artery.