Nicotine induced inhibition of the activities of accessory reproductive ducts in male rats

A Critical Review and Scientific Prospective on Contraceptive Therapeutics from Ayurveda and Allied Ancient Knowledge

Commonly used synthetic or prescribed hormonal drugs are known to interfere with the endocrine system and may have adverse reproductive, neurological, developmental, and metabolic effects in the body. These may also produce adverse effects such as polycystic ovarian disorder, endometriosis, early puberty, infertility or toxicity to gonads, testicular germ cell cancer, breast or prostate cancer, brain developmental problems, and even birth defects. Globally, the emergence of renewed interest in natural products for reproductive health is on the rise, which offers opportunities for new contraceptive developments. The search for alternate, safer contraceptive products or agents of natural origin is of scientific interest. Ayurvedic classical texts offer knowledge and information about the reproductive function and therapeutics including those for enhancement and limiting male and female fertility. Review of ancient, medieval, and recent—including texts on erotica that provide information on approaches and large numbers of formulations and drugs of plant, mineral or animal origin—claimed to have sterilizing, contraceptive, abortifacient, and related properties is presented. Few among these are known to be toxic and few are not so common. However, most of the formulations, ingredients, or modes of administration have remained unattended to, due to issues related to consumer compliance and limitations of standardization and lack of appropriate validation modalities. Several of these ingredients have been studied for their phytoconstituents and for the variety of pharmacological activities. Efforts to standardize several classical dosage forms and attempts to adapt to modern technologies have been made. List of formulations, ingredients, and their properties linked with known constituents, pharmacological, biological, and toxicity studies have been provided in a series of tables. The possible effectiveness and safety of selected formulations and ingredients have been examined. Suggestions based on new drug delivery systems integrated with advances in biotechnology, to provide prospects for new therapeutics for contraception, have been considered. Ayurveda is built on a holistic paradigm of biological entity rather than limited gonadal functions. Graphic presentation of a few carefully chosen possibilities has been depicted. New approaches to standardization and ethnopharmacological validation of natural contraceptive therapeutics may offer novel mechanisms and modalities and therapeutic opportunities to satisfy unmet needs of contraception.

Protective effect of Nigella sativa oil against acetamiprid induced reproductive toxicity in male rats

The present study was designed to investigate the adverse reproductive effects of acetamiprid, besides the possible protective role of Nigella sativa oil (NSO), as a potential antioxidant agent. Thirty-two male Wistar rats were allocated into four equal groups of eight, control (CRL), acetamiprid (ACMP, 27 mg/kg), Nigella sativa oil (NSO, 0.5 ml/kg) and in combination (ACMP + NSO). The experimental animals were dosed by gavage (5 days per week) for 45 consecutive days. Body weight gain, reproductive organs weights, sperm characteristics, testosterone, and thiobarbutiric acid-reactive substances (TBARS) levels were investigated. The obtained results showed that ACMP decreased significantly (p < 0.001) the body weight gain and the absolute weights of reproductive organs (testes, epididymis, and seminal vesicles). Furthermore, significant alterations at least (p < 0.01) in semen characteristics were noted in ACMP group as evidenced by a decline in spermatids number, sperm count, sperm motility, and testosterone level with an increase in abnormal and dead sperm and TBARS level. Treatment with NSO alone may stimulate spermatogenesis, increased significantly (p < 0.001) spermatids number and the weight of seminal vesicles. On the other hand, the co-administration of NSO along with ACMP can mitigate more efficiently and modulate in certain cases the adverse effects induced by ACMP on reproductive organs weights, semen quality, testosterone, and TBARS levels (at least p < 0.001). This obvious protective role of NSO against ACMP induced reproductive toxicity may be due to its antioxidant properties and ability to reduce TBARS levels as shown in this work.

Review on Research of Suppression Male Fertility and Male Contraceptive Drug Development by Natural Products

Male contraceptive development in the present scenario is most viable aspect of research due to uncontrolled population growth in the world. In this respect investigators are busy to find out a safe male contraceptive drug. Researchers have started their finding for a suitable drug from natural sources because these are safe and easily acceptable for common man, most of natural sources are plants and their products. In this review 137 plants and their effects on reproduction and reproductive physiology are summarized. Some of them have intense effect on male reproductive system and do not produce any side effects. Reproductive toxicological studies are also important aspects of these kinds of researches, so it is important that drugs are safe and widely acceptable. An ideal male contraceptive can influence semen, testes, hormone level, accessory reproductive organs and general physiology of animals and produced some alterations. Many plants in this review are showing antifertility as well as antispermatogenic effects, so these may be used for further study for contraceptives development but it is important to find out the mechanism of reaction and further laboratory and clinical research on some plants are needed for final male contraceptive drug development. In conclusion this review will help for finding suitable plant products for male contraceptive clinical and laboratory studies.

Histological changes in male accessory reproductive organs in rats exposed to cigarette smoke and the protective effect of honey supplementation

The effect of cigarette smoke (CS) on histology of male accessory reproductive organs and the possible protective effect of honey supplementation in rats were investigated in this study. Rats received distilled water, honey, CS exposure or honey plus CS exposure. Honey (1.2 g/kg body weight/day) was administered by gavage and CS exposure (3 times per day) was done in a chamber for 13 weeks. CS exposure significantly increased relative weight of epididymis and ventral prostate. There were also significantly increased number of clear cells and epithelial height of cauda epididymis as well as severe interstitial oedema and decreased epithelial height of prostate gland. However, with the supplementation of honey, these histological changes were significantly reversed suggesting the protective effect of honey against the toxic effect of CS on male accessory reproductive organs in rats.

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.

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.

Study on prevention of two-stage skin carcinogenesis by Hibiscus rosa sinensis extract and the role of its chemical constituent, gentisic acid, in the inhibition of tumour promotion response and oxidative stress in mice

We designed the present study to investigate the role of gentisic acid in the chemopreventive activity of Hibiscus rosa sinensis extract on 7,12-dimethyl benz(a)anthracene (DMBA)/croton oil-mediated carcinogenesis in mouse skin via 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced tumour promotion response and oxidative stress. Single topical application of DMBA followed by twice weekly applications of croton oil after one week for 20 weeks resulted in 100% incidence of tumours in animals in 15 weeks. However, application of H. rosa sinensis extract 30 minutes prior to the application of croton oil twice weekly for 20 weeks caused significant reduction in the number of tumours per mouse and the percentage of tumour-bearing mice. Also, the latency period for the appearance of the first tumour was delayed on H. rosa sinensis pretreatment. A single topical application of TPA caused significant depletion in reduced glutathione (GSH) content, activities of its metabolizing and antioxidant enzymes, while malondialdehyde (MDA) formation, H2O2 content, ornithine decarboxylase (ODC) activity and DNA synthesis were significantly increased. Interestingly, pretreatment of H. rosa sinensis extract (3.5 mg and 7 mg/kg body weight) and gentisic acid (2.0 microg and 4.0 microg/0.2 ml acetone per animal) restored the levels of GSH, and its metabolizing and antioxidant enzymes (P<0.05). There was also a statistically significant reduction in MDA formation and H2O2 content (P<0.05) at both doses. Although inhibition of ODC activity by gentisic acid was not dose-dependent, thymidine incorporation in DNA (P<0.05) was dose-dependently recovered by the plant extract and its chemical constituent. We therefore propose that gentisic acid has a role in the modulatory activity of H. rosa sinensis extract.

A review on potentiality of medicinal plants as the source of new contraceptive principles

Recently, a review has already been made on the synthetic contraceptive agents whereas this review embraces the natural contraceptives upto year 2001 with 355 references. It also includes the isolation of their active principles, methods of analysis of active ingredients through TLC, HPLC, their side effects and pharmacological action.