A characterization of the antioxidant enzyme activity and reproductive toxicity in male rats following sub-chronic exposure to areca nut extracts

Sialylation: fate decision of mammalian sperm development, fertilization, and male fertility†

Sperm development, maturation, and successful fertilization within the female reproductive tract are intricate and orderly processes that involve protein translation and post-translational modifications. Among these modifications, sialylation plays a crucial role. Any disruptions occurring throughout the sperm's life cycle can result in male infertility, yet our current understanding of this process remains limited. Conventional semen analysis often fails to diagnose some infertility cases associated with sperm sialylation, emphasizing the need to comprehend and investigate the characteristics of sperm sialylation. This review reanalyzes the significance of sialylation in sperm development and fertilization and evaluates the impact of sialylation damage on male fertility under pathological conditions. Sialylation serves a vital role in the life journey of sperm, providing a negatively charged glycocalyx and enriching the molecular structure of the sperm surface, which is beneficial to sperm reversible recognition and immune interaction. These characteristics are particularly crucial during sperm maturation and fertilization within the female reproductive tract. Moreover, enhancing the understanding of the mechanism underlying sperm sialylation can promote the development of relevant clinical indicators for infertility detection and treatment.

Prognostic value and clinicopathological status of PD-L1 expression and CD8+ TILs in oral squamous cell cancer patients with or without traditional risk factors

BACKGROUND

Non-smokers, non-drinkers, and non-betel quid chewers (NSNDNBs) with oral squamous cell carcinoma (OSCC) have poor survival outcomes. Tumor microenvironment based on PD-L1/CD8+ T cell infiltrated lymphocyte (TIL) proportion is proposed as a prognostic indicator.

METHODS

Immunohistochemistry staining was performed on OSCC samples from 64 patients. The PD-L1/CD8+ TILs were scored and stratified into four groups. Disease-free survival (DFS) was analyzed using a Cox regression model.

RESULTS

OSCC in NSNDNB patients was associated with female sex, T1-2 classification, and PD-L1 positivity. Low CD8+ TILs correlated with perineural invasion. High CD8+ TILs correlated with improved DFS. PD-L1 positivity was not correlated with DFS. Type IV tumor microenvironment yielded the highest DFS (85%).

CONCLUSION

NSNDNB status relates to PD-L1 expression regardless of CD8+ TILs infiltration. Type IV tumor microenvironment was associated with the best DFS. High CD8+ TILs resulted in better survival, while PD-L1 positivity alone was not correlated to DFS.

Chemical Composition, Pharmacological, and Toxicological Effects of Betel Nut

Betel nut, the fruit of Areca catechu L, has a long medical history in Southeast Asia. It is native to Malaysia and is cultivated and processed extensively in subtropical regions, such as South China and India. Betel nut almost appears as a "snack" in various occasions in most parts of China. Clinically, betel nut can play a certain pharmacology role and was used in malaria, ascariasis, arthritis, enterozoic abdominalgia, stagnation of food, diarrhea, edema, and beriberi. The nervous excitement of betel nut chewing has made it gradually become popular. However, chewing betel nut can induce oral submucosal fibrosis (OSF) and oral cancer (OC). At the same time, long-term chewing of betel nut also causes inhaled asthma, sperm reducing, betel quid dependence (BQD), and uterine and esophageal cancers. The main components of processed betel nut are the goal of this review. This study will mainly start from the pharmacological activity and toxicology study of betel nut in recent years, aiming to seek its advantages and disadvantages. In the meantime, this study will analyze and emphasize that betel nut and arecoline are the high-risk factors for oral cancer, which should arouse attention and vigilance of the public.

Metformin protects against mouse oocyte apoptosis defects induced by arecoline

OBJECTIVES

Arecoline is the main bioactive substance extracted from Areca catechu L, which has cell, neural and genetic toxicity. The function of arecoline in reproductive system has not been well explored.

MATERIALS AND METHODS

To investigate the toxic effects of arecoline on oocyte development, immunofluorescence staining, qPCR, Western blotting, sperm binding assays and in vitro fertilization were performed to evaluate oocyte meiosis competence and embryo development.

RESULTS

Our data revealed that arecoline exposure disrupts actin filament dynamics, spindle assembly and kinetochore-microtubule attachment stability in mouse oocytes, leading to aneuploidy and oocyte meiosis arrest. In addition, arecoline treatment disturbs the distribution of mitochondria, reduces ATP production and increases the level of oxidative stress, which ultimately induces oocyte apoptosis. Supplementation with metformin, a medicine for type 2 diabetes in the clinic, partially alleviates these damages.

CONCLUSIONS

Metformin has a protective effect on arecoline-induced mouse oocytes apoptosis.

A comparison for the effects of raw, smoked, and smoked and brined areca nut extracts on the immune and inflammatory responses in the Kunming mice

Chewing of areca nuts is quite popular in various regions worldwide. Previous studies have demonstrated the pharmacological and toxicological effects of fresh areca nuts. However, processed areca nuts, which are popular in the Hunan province of China, have not been extensively studied for its biological effect. This study aimed at investigating the impact of the acrea nut extracts (ANE) prepared from the raw material, the semi-product, and the final product on the immune system and inflammation-related markers in the Kunming mice. The mice were assigned to seven different groups and administered different ANE at two concentrations (1X and 5X) for four weeks. Total body weight gain and organ coefficient of the liver, spleen, and kidney, as well as the immune system and inflammation-related markers were evaluated. The results revealed that processed areca nuts have a much milder effect on the mice immune system and some inflammatory markers than fresh areca nut in the Kunming mice. PRACTICAL APPLICATIONS: Chewing various forms of areca nuts is popular in China, Southeast Asia, and other regions. People from Hunan, China prefer to chew a processed areca nut, which has rarely been studied. This manuscript explores the effects of three kinds of areca nut extracts on the immune system- and inflammation-related indicators in Kunming mice. The obtained results revealed that processed areca nuts had significantly milder effects than the raw nut/nut extract, particularly on the body weight, immune responses, and inflammatory markers. The results of the present study provide some new directions for the areca nut industry and raise public awareness for the undesirable effects of areca nuts.

Toxicity and Its Mechanism Study of Arecae semen Aqueous Extract in Wistar Rats by UPLC-HDMS-Based Serum Metabolomics

Background

Arecae semen (AS) is officially recorded in Chinese Pharmacopoeia and it is known for its multiple functions, including antidepressive, antioxidant, anti-inflammatory, and cholesterol-lowering effects, which have been confirmed by modern pharmacological study. Previous study in our laboratory showed that long-term oral administration of Arecae semen (AS) is officially recorded in Chinese Pharmacopoeia and it is known for its multiple functions, including antidepressive, antioxidant, anti-inflammatory, and cholesterol-lowering effects, which have been confirmed by modern pharmacological study. Previous study in our laboratory showed that long-term oral administration of Hypothesis. The aim of this work was to characterize the metabolome, evaluate the metabolic changes, and study the mechanisms of the toxicity induced by different treatment doses of ASAE via metabolomics.

Methods

Wistar rats were administered orally two different doses of ASAE (1500 and 4500 mg/kg/d) for 30 days. The investigation was carried out to evaluate the safety of ASAE. And, the UPLC-HDMS-based serum metabolomics in conjunction with multivariate statistical techniques was applied to investigate the serum metabolite profile and potential markers of toxicity induced by different doses of ASAE.

Results

Coupled with blood biochemistry and histopathology results, the significant difference in metabolic profiling was observed between 1500 and 4500 mg/kg/d dosages of ASAE-treated rats and normal rats by using pattern recognition analysis, indicating that changes in serum metabolites must have occurred. Some significant changed metabolites such as arachidonic acid, linoleic acid, stearic acid, and LPC (18 : 1) have been found and identified. These biochemical changes in serum metabolites are related to the perturbation of linoleic acid metabolism, arachidonic acid metabolism, glycerophospholipid metabolism, and purine metabolism, which may be helpful to further understand the cardiotoxicity and neurotoxicity of ASAE.

Conclusion

The study shows that the metabolomic method may be a valuable tool for studying the essence of toxicity induced by traditional Chinese medicine.

Consumption of betel quid contributes to sensorineural hearing impairment through arecoline-induced oxidative stress

Betel quid is one of the most widely used psychoactive substances, and is consumed by approximately 10% of the world’s population. In addition to its carcinogenicity, betel quid has also been reported to affect many organs, including the brain, heart, lungs, gastrointestinal tract, and reproductive organs. As betel quid contains several neurotoxic ingredients, we hypothesize that it also possesses ototoxicity and may lead to sensorineural hearing impairment (SNHI). In this study, we investigated the contribution of betel quid consumption to SNHI in a large clinical cohort, and validated the pathogenetic mechanisms in ex vivo tissue explants. We enrolled a total of 2364 volunteers, and determined their audiologic results based on Z-scores converted from their original frequency-specific hearing thresholds. Using generalized linear regression, we identified a positive correlation between betel quid consumption and the Z-scores across different frequencies. Subsequently, we explored the toxicity of arecoline, the main neuroactive component of betel quid, on tissue explants from murine cochleae. Arecoline reduced cell activity in the explant cultures and induced apoptosis in the hair cells, probably through the effects of oxidative stress. These findings have expanded the potential hazards of betel quid to common neurological disorders, and provide insights into preventive strategies against SNHI caused by neurotoxic substances.

Ameliorative effects of Saussurea lappa root aqueous extract against Ethephon-induced reproductive toxicity in male rats

This study was designed to evaluate protective effect of Saussurea lappa root aqueous extract against Ethephon (2-chloroethylphosphonic acid)-induced reproductive toxicity in rats. Control group received distilled water. Second group was given S. lappa extract at a dose 50 mg/kg bw. Third group was given Ethephon at a dose 200 mg/kg bw. Fourth, fifth, and sixth groups were given S. lappa extract before, with or after Ethephon administration, respectively. Ethephon intoxication significantly decreased serum levels of follicle stimulating hormone, luteinizing hormone, testosterone, and prolactin. Also, it significantly decreased sperms count, vitality, morphology index, total motility, progressive motility, and proliferating cell nuclear antigen protein expressions in spermatogonia. However, it significantly increased sperms abnormalities, testicular tissue and DNA damages, P53 protein expressions, noprogressive motility, and immotile sperms. In contrast, S. lappa extract ameliorated these alterations. These results indicated that S. lappa had potential preventive and curative effects against Ethephon-induced reproductive toxicity in rats.

Sub-chronic toxicity study of arecae semen aqueous extract in Wistar rats

ETHNOPHARMACOLOGICAL RELEVANCE

Arecae semen, the ripe seed of Areca catechu L., has been used as vermifuge and digestant in traditional Chinese medicine (TCM). However, the potential toxicity effect of arecae semen has not been completely investigated.

THE AIM OF THE STUDY

The present study was aimed at evaluating the sub-chronic toxicity of arecae semen by oral administration in Wistar rats.

MATERIALS AND METHODS

A total of 120 Wistar rats were randomly divided into 4 groups (15 males and 15 females per group). The treated groups were given arecae semen aqueous extract (ASAE) at the dose of 750, 1500 and 4500mg/kg/day by oral administration respectively, and the control group was received distilled water only. The rats and their consumed feed were weighted every 3 days. The clinical changes and mortality were observed and recorded daily. Hematological parameters, biochemical parameters, organ weights, urinalysis and histopathological examination of all rats were tested at the end of the 30-day treatment period and another 10-day recovery period.

RESULTS

Deaths, weight loss, diarrhea, sluggish action, tremors and body curl up were observed in the 1500 and 4500mg/kg groups during the study. The relative organ weights of liver and testis in male rats of 4500mg/kg group were significantly different compared with the control group at the end of the treatment period. As for laboratory parameters, there were no significant differences at the dose of 1500 and 4500mg/kg groups compared with the control group in the study, except the white blood cell count (WBC), aspartate aminotransferase (AST), alanine aminotransferase (ALT), albumin (ALB), blood urea nitrogen (BUN), creatinine (Cr), glucose (GLU) and total cholesterol (CHOL). In addition, the results of histopathological examination and feed intake showed no significant difference compared with the control group.

CONCLUSIONS

The results showed that ASAE at the dose of 750mg/kg/day was safe, but long-term oral administration of ASAE with high dosage was toxic. Moreover, the toxic ingredients of ASAE including arecoline, and also some other compounds should be researched.

Adverse Health Effects of Betel Quid and the Risk of Oral and Pharyngeal Cancers

Global reports estimate 600 million betel quid (BQ) chewers. BQ chewing has been demonstrated not only to be a risk factor for cancers of the oral cavity and pharynx and oral potentially malignant disorders (OPMD) but also to cause other cancers and adverse health effects. Herein, we summarized the international comparison data to aid in the understanding of the close relationship between the prevalence of BQ chewing, the occurrence of oral and pharyngeal cancers, and adverse health effects. Potential biomarkers of BQ carcinogens, such as areca nut, alkaloids, and 3-methylnitrosaminopropionitrile (MNPN), are closely associated with human health toxicology. Molecular mechanisms or pathways involving autophagy, hypoxia, COX-2, NF-κB activity, and stemness are known to be induced by BQ ingredients and are very closely related to the carcinogenesis of cancers of oral and pharynx. BQ abuse-related monoamine oxidase (MAO) gene was associated with the occurrence and progress of oral and pharyngeal cancers. In summary, our review article provides important insights into the potential roles of environmental BQ (specific alkaloid biomarkers and nitrosamine products MNPN) and genetic factors (MAO) and offers a basis for studies aiming to reduce or eliminate BQ-related OPMD and oral/pharyngeal cancer incidences in the future.

Screening and Identification of the Metabolites in Rat Plasma and Urine after Oral Administration of Areca catechu L. Nut Extract by Ultra-High-Pressure Liquid Chromatography Coupled with Linear Ion Trap-Orbitrap Tandem Mass Spectrometry

Areca catechu L. nut, a well-known toxic traditional herbal medicine, has been widely used to treat various diseases in China and many other Asian countries for centuries. However, to date the in vivo absorption and metabolism of its multiple bioactive or toxic components still remain unclear. In this study, liquid chromatography coupled with tandem mass spectrometry was used to analyze the major components and their metabolites in rat plasma and urine after oral administration of Areca catechu L. nut extract (ACNE). A total of 12 compounds, including 6 alkaloids, 3 tannins and 3 amino acids, were confirmed or tentatively identified from ACNE. In vivo, 40 constituents, including 8 prototypes and 32 metabolites were identified in rat plasma and urine samples. In summary, this study showed an insight into the metabolism of ACNE in vivo, which may provide helpful chemical information for better understanding of the toxicological and pharmacological profiles of ACNE.

Selective constraints on protamine 2 in primates and rodents

BACKGROUND

Protamines are sperm nuclear proteins with a crucial role in chromatin condensation. Their function is strongly linked to sperm head morphology and male fertility. Protamines appear to be affected by a complex pattern of selective constraints. Previous studies showed that sexual selection affects protamine coding sequence and expression in rodents. Here we analyze selective constraints and post-copulatory sexual selection acting on protamine 2 (Prm2) gene sequences of 53 species of primates and rodents. We focused on possible differences in selective constraints between these two clades and on the two functional domains of PRM2 (cleaved- and mature-PRM2). We also assessed if and how changes in Prm2 coding sequence may affect sperm head dimensions.

RESULTS

The domain of Prm2 that is cleaved off during binding to DNA (cleaved-Prm2) was found to be under purifying selection in both clades, whereas the domain that remains bound to DNA (mature-Prm2) was found to be positively selected in primates and under relaxed constraint in rodents. Changes in cleaved-Prm2 coding sequence are significantly correlated to sperm head width and elongation in rodents. Contrary to expectations, a significant effect of sexual selection was not found on either domain or clade.

CONCLUSIONS

Mature-PRM2 may be free to evolve under less constraint due to the existence of PRM1 as a more conserved and functionally redundant copy. The cleaved-PRM2 domain seems to play an important role in sperm head shaping. However, sexual selection on its sequence may be difficult to detect until it is identified which sperm head phenotype (shape and size) confers advantages for sperm performance in different mammalian clades.

Areca catechu L. (Arecaceae): a review of its traditional uses, botany, phytochemistry, pharmacology and toxicology

ETHNOPHARMACOLOGICAL RELEVANCE

Areca catechu L. (Arecaceae), widely distributed in South and Southeast Asia, is a popular traditional herbal medicine that can be chewed for the purpose of dispersing accumulated fluid in the abdominal cavity and killing worms. The present paper aims to provide an up-to-date review on the traditional uses and advances in the botany, phytochemistry, pharmacology and toxicology of this plant. Furthermore, the possible trends and a perspective for future research of this plant are also discussed.

MATERIALS AND METHODS

A literature search was performed on A. catechu based on classic books of herbal medicine, PhD. and MSc. dissertations, government reports, the state and local drug standards, scientific databases including Pubmed, SciFinder, Scopus, the Web of Science, Google Scholar, and others. Various types of information regarding this plant are discussed in corresponding parts of this paper. In addition, perspectives for possible future studies of A. catechu are discussed.

RESULTS

The seeds of A. catechu (areca nut) have been widely used in clinical practice in China, India and other South and Southeast Asian Countries. Currently, over 59 compounds have been isolated and identified from A. catechu, including alkaloids, tannins, flavones, triterpenes, steroids, and fatty acids. The extracts and compounds isolated from A. catechu have many pharmacological activities. These include antiparasitic effects, anti-depressive effects, anti-fatigue effects, antioxidant effects, antibacterial and antifungal effects, antihypertensive effects, anti-inflammatory and analgesic effects, anti-allergic effects, the promotion of digestive functions, suppression of platelet aggregation, regulatory effects on blood glucose and lipids, etc. Although arecoline is the primary active constituent of A. catechu, it is also the primary toxic compound. The main toxicities of arecoline are the promotion of oral submucosal fibrosis (OSF) and cytotoxic effects on normal human cells, which involve inducing apoptosis.

CONCLUSION

As an important herbal medicine, A. catechu has potential for the treatment of many diseases, especially parasitic diseases, digestive function disorders, and depression. Many traditional uses of A. catechu have now been validated by current investigations. However, further research should be undertaken to investigate the clinical effects, toxic constituents, target organs, and pharmacokinetics and to establish criteria for quality control for A. catechu-derived medications. In addition, it will be interesting to investigate the active macromolecular compounds and active constituents other than alkaloids in both raw and processed products of A. catechu.

Arecoline induces TNF-alpha production and Zonula Occludens-1 redistribution in mouse Sertoli TM4 cells

Background

Arecoline, a major alkaloid in Areca nut has the ability to induce oxidative stress. The effect of Areca nut, arecoline on reducing sperm quality and quantity were documented previously using several animal models. Junction disruption by down-regulation of the junction-adhesive protein via oxidative stress is an important route mediating abnormal spermatogenesis. Therefore, in this present study, we investigated the functional role of arecoline on junctional proteins.

Results

To analyze direct effects of arecoline on testis cells, confluent mouse testicular Sertoli cell line TM4 was exposed to arecoline. Arecoline decreased insoluble zonula occludens-1 (ZO-1) protein expression in TM4 cells, however, arecoline treatment increased TNF-alpha production in both TM4 and monocytic THP1 cells. In addition, ERK1/2 inhibitor PD98059 reversed arecoline effects on TNF-alpha and ZO-1.

Conclusions

Arecoline increases the production of TNF-alpha and induces protein redistribution of ZO-1. All these results explain the role of arecoline in male reproductive dysfunction, besides its cytotoxic induction.

Electronic supplementary material

The online version of this article (doi:10.1186/s12929-014-0093-z) contains supplementary material, which is available to authorized users.

The hepatotoxicity and testicular toxicity induced by arecoline in mice and protective effects of vitamins C and e

Arecoline is a major alkaloid of areca nuts which are widely chewed by southeast Asian and it manifests various toxic effects in different organs of human and animals. In this work, mature mice were treated by vitamins C plus E, arecoline, or both daily for four weeks. The results showed that arecoline significantly increased the levels of serum alkaline phosphatase (ALP), glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) and significantly decreased the levels of reduced glutathione (GSH), glutathione-S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT) in the liver tissues. Additionally, the body weight, testis weight, sperm counts, motility and normal sperms also were significantly decreased. The supplement of vitamins C and E can bring the activities of ALP and GPT to normal levels and partially restore the sperm counts compared to the arecoline-treated group but have no other positive effects. In conclusion, the vitamins C and E partially attenuated the arecoline-induced hepatotoxiciy but basically had on protective effects against the arecoline-induced testicular toxicity.

A review of the systemic adverse effects of areca nut or betel nut

Areca nut is widely consumed by all ages groups in many parts of the world, especially south-east Asia. The objective of this review is to systematically review and collate all the published data that are related to the systemic effects of areca nut. The literature search was performed by an electronic search of the Pubmed and Cochrane databases using keywords and included articles published till October 2012. We selected studies that covered the effect of areca nut on metabolism, and a total of 62 studies met the criteria. There is substantial evidence for carcinogenicity of areca nut in cancers of the mouth and esophagus. Areca nut affects almost all organs of the human body, including the brain, heart, lungs, gastrointestinal tract and reproductive organs. It causes or aggravates pre-existing conditions such as neuronal injury, myocardial infarction, cardiac arrhythmias, hepatotoxicity, asthma, central obesity, type II diabetes, hyperlipidemia, metabolic syndrome, etc. Areca nut affects the endocrine system, leading to hypothyroidism, prostate hyperplasia and infertility. It affects the immune system leading to suppression of T-cell activity and decreased release of cytokines. It has harmful effects on the fetus when used during pregnancy. Thus, areca nut is not a harmless substance as often perceived and proclaimed by the manufacturers of areca nut products such as Pan Masala, Supari Mix, Betel quid, etc. There is an urgent need to recognize areca nut as a harmful food substance by the policy makers and prohibit its glamorization as a mouth freshener. Strict laws are necessary to regulate the production of commercial preparations of areca nut.

Tobacco and areca nut chewing--reproductive impairments: an overview

A large number of people are using smokeless tobacco and areca nut worldwide. Sufficient data on tobacco smoking have harmful effect on human health and reproduction is available. However, data on the smokeless tobacco and areca nut use on human reproduction is scanty. This overview is an attempt to compose on the consumption of smokeless tobacco and areca nut on human reproduction and some relevant experimental data were also included. The existing studies suggest that tobacco and areca nut chewing alone, together or with other ingredients had reproductive toxic potential. Pregnant women using smokeless tobacco during pregnancy also had adverse effect on pregnancy and its outcome. Thus pregnant women must avoid consumption of any mixture containing areca nut and tobacco in order to protect the pregnancy and outcome. The data suggest that smokeless tobacco use is also harmful as smoking for reproduction and use of areca nut might have further compounded the problem.

Alkaloids from areca (betel) nuts and their effects on human sperm motility in vitro

An improved high-performance liquid chromatography (HPLC) method was established to rapidly and simultaneously determine 3 main alkaloids (arecoline, arecaidine, and guvacine) in areca (betel) nuts (AN), and 12 AN samples from the main betel palm growing areas on the Chinese Mainland were collected and determined. Semen samples from acceptable volunteers were treated in vitro with different concentrations of the 3 alkaloids to evaluate the effects on sperm motility (SM). Highly motile spermatozoa were selected from the samples and divided into 5 equal fractions. Various concentrations of each alkaloid were added to 4 of the 5 fractions, and 1 fraction was used as a control. All fractions were incubated for 4 h. A computer-aided sperm analysis system was used to measure 5 SM parameters, motility, average path velocity, straight-line velocity, curvilinear velocity, linearity, and amplitude of lateral head displacement. The results showed that the contents of the amount of alkaloids in AN differed markedly in different places in China and were higher in the kernel than in the husk, and higher in dried AN than in fresh AN. Arecoline had the strongest reduction effect on human SM and the effect was strongly dose dependent. Arecaidine had a much weaker reduction effect than arecoline, and guvacine had the least reduction effect. These findings also demonstrate that betel quid could have adverse effects on the gonadal functions of betel quid consumers.

Monoamine oxidase A variants are associated with heavy betel quid use

Few studies have investigated whether genetic abnormalities predispose individuals to heavy betel quid (BQ) use. One of the major ingredients of BQ, arecoline, is known to affect the expression of monoamine oxidase A (MAO-A). We investigated the extent to which arecoline inhibits MAO-A expression and the role of MAO-A polymorphisms in BQ use in Taiwanese aborigines. Cytotoxicity assays, microarrays and quantitative reverse transcriptase-polymerase chain reaction were used to examine the effects of arecoline and areca nut extract (ANE) on cell viability and MAO-A expression in neuroblastoma SH-SY5Y cells. After identifying the effective concentrations of arecoline and ANE in vitro, we examined the in vivo effects of these compounds using a rat model system. Our results indicate that arecoline and ANE inhibit MAO-A expression both in vitro and in vivo. In addition, we examined the correlation between plasma MAO-A activity and cumulative exposure to BQ in humans. We recruited 1307 aborigines from a large-scale community-based survey to determine whether MAO-A variants were associated with high BQ use and a preference for use with smoking or alcohol and whether gender bias existed. MAO-A expression was significantly downregulated by arecoline and ANE at 100-200 µg/ml and in rat whole brains on days 30 and 45. MAO-A activity levels in human plasma were positively correlated with the extent of BQ exposure, and individuals with at-risk alleles exhibited lower activity, although this result did not reach statistical significance. We found two single nucleotide polymorphism (SNPs) in aboriginal males [rs2283725, odds ratio (OR) = 2.04; rs5953210, OR = 2.03] and females (rs2283725, OR = 1.54; rs5953210, OR = 1.59) that were associated with heavy BQ use. Those individuals carrying at-risk alleles who drank alcohol were twice as likely to be heavy BQ users. However, the effects of these SNPs on BQ use were significant even after controlling for alcohol use. Our results suggest that two specific loci may confer a susceptibility to BQ abuse and affect MAO-A enzymatic activity.

Effects on spermatogenesis in swiss mice of a protein isolated from the roots of Ricinus communis (Linn.) (Euphorbiaceae)

This study was aimed to evaluate the effect on spermatogenesis of a 62 kDa protein (Rp) isolated from 50% ethanolic extract of the root of Ricinus communis in mice. A dose response study in mice revealed that 25mg/kg body weight/day was the most effective dose. Swiss strain mature male mice of 30 days old were divided into two group namely control and Rp treated (25mg/kg body weight/day). The study showed that sperm motility and count were decreased significantly in the treated group as compared to the control. The fertility index of the treated groups was reduced by 100%. The activity of HMG Co A reductase and cholesterol were increased significantly in the treated group. The testicular activities of 3βHSD, 17βHSD, glucose 6-phosphate dehydrogenase and malic enzyme and the level of serum testosterone were decreased significantly in the treated group. The expression of 3βHSD and 17βHSD were decreased and the expression of StAR increased significantly in the treated group as compared to the control. Proteolytic digestion of the native protein with trypsin and chymotrypsin showed that the proteolytic cleavage did not affect the spermicidal action of Rp. Hence this study can be concluded that Rp impaired spermatogenesis in vivo by suppressing the production of testosterone.

Assessment of sperm production and reproductive organs of Wistar rats to long-term exposure of Caesalpinia ferrea

Caesalpinia ferrea Mart (Leguminosae) is a medicinal plant used to treat diabetes, among other therapeutic properties, but which is also reported to have hepatotoxic effects. Although it contains substances such as flavonoids and coumarin, which are known to have antifertility activity, no studies have apparently been conducted to evaluate the potential adverse side effects of this plant on the function of the reproductive system after a chronic treatment. Therefore, this investigation was carried out to evaluate the effect and safety of the long-term exposure to C. ferrea on male Wistar rats' vital organs, reproductive system and sperm production. Adult and immature male rats were treated with an aqueous extract of C. ferrea at a dose level of 300 mg/kg of body weight, administered during one or two spermatogenic cycles of this species. The reproductive and vital organs were analyzed, and sperm was collected from the epididymal secretion of the right epididymis cauda. The long-term administration of C. ferrea did not significantly alter the body, vital and reproductive organs weights. Gamete production was not affected either. The chronic assessment of C. ferrea suggests that this plant does not affect the normal functioning of the Wistar rat reproductive system.