Immunohistological localization of insulin-like growth factor binding protein-1 in primary implantation sites and trauma-induced deciduomal tissues of the rhesus monkey

We have earlier demonstrated that there is a close similarity in the temporo-spatial pattern in the onset of oedema, epithelial-plaque transformation, stromal decidualization and influx of granulated lymphocytes in artificially trauma-induced deciduomal endometrium with such events in maternal endometrium at the primary implantation site during early stages of pregnancy in the rhesus monkey. In the present study, we have immunohistochemically examined whether the pattern of insulin-like growth factor-binding protein 1 (IGFBP-1) protein expression in conceptus tissue and maternal endometrium during lacunae and villous placenta stages of gestation in the rhesus monkey is developmental stage-specific and whether a discernible difference exists in the temporo-spatial characteristics of IGFBP-1 protein expression between conceptus associated implantation-decidualization and trauma induced deciduoma in the rhesus monkey. Trophoblast cells failed to exhibit IGFBP-1 immunopositive staining at any stage of implantation-placentation studied. Epithelial cells in plaque acini, endothelial cells, and vascular smooth muscle also did not show any immunopositive staining for IGFBP-1 in samples of primary implantation sites and trauma-induced deciduoma. Maternal endometrial epithelial and stromal-decidual cells however exhibited a temporal and spatial pattern of IGFBP-1 expression in cell-type specific manner and clear distinctions were observed between conception and deciduoma samples. Our results suggest that IGFBP-1 expression is highly tissue and development-specific and that conceptus-derived signals are necessary to initiate the glandular expression of IGFBP-1 during the early stage of gestation.

Studies on the production and purification of an antimicrobial compound and taxonomy of the producer isolated from the marine environment of the Sundarbans

A microorganism isolated from the Sundarbans region of the Bay of Bengal, India, showed potent antimicrobial activity against gram-positive and gram-negative bacteria, molds, yeast and several multiple-drug-resistant (MDR) bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). The isolate grew in the presence of 20% (w/v) NaCl, antibiotic production being maximum with 5% (w/v) NaCl in the production medium. Natural seawater stimulated antibiotic biosynthesis. The absence of catabolite repression during the synthesis of the antimicrobial substance was demonstrated by the utilization of glucose by this isolate. The 16S rRNA gene of this aerobic, gram-positive, mycelium- and spore-forming microorganism was amplified, and molecular phylogenetic analysis of the DNA sequence showed less than 93% similarity with its closest relative, indicating differentiation at the genus level. The highly stable, active principle was purified by butyl acetate extraction and silica-gel chromatography and a single compound was found to posses the broad-spectrum activity. Molecular characterization showed that the active compound is a lipid. Bioreactor studies demonstrated that antibiotic production is strongly dependent on the scale of operation and there is a definite relation between the dissolved oxygen concentration, medium pH, glucose utilization, cell differentiation and antibiotic production. Maximum production in 30 h could be obtained by regulation of the medium pH in the alkaline range by a combination of controlled addition of NaOH, regulation of the air supply and changes in the reactor configuration. Considering all of the above evidences and based on comparison with the current literature, a novel antimicrobial appears to have been isolated.

Immunostimulatory Role of Tryptic Digest ofAbrusAgglutinin

Many bioactive peptides are in therapeutic use as immunomodulators at present. The origin of these bioactive peptides is diverse. Such bioactive peptides are reported to be present in enzymatic digest of food and milk proteins. In our previous work we have reported that Abrus agglutinin retains its bioactivity even after heat denaturation but loses its haemagglutination properties. This leads to the supposition that immunostimulatory regions in the protein might be responsible for its in vivo and in vitro stimulatory properties. Thus the bioactivity of tryptic digest of Abrus agglutinin (TDA) was checked in vitro to ascertain the presence of some bioactive region in the protein, which will lead to the discovery of certain immunostimulatory peptides which might be of use in nonspecific immunotherapy. In this study it is observed that TDA stimulates macrophage increasing the phagocytic and bactericidal activity as well as hydrogen peroxide production. TDA also proliferates splenocytes leading to Th1 response and NK cell activation.

Simultaneous increase in germ cell apoptosis and oxidative stress under acute unilateral testicular ischaemia in rats

Ischaemia induced germ cell apoptosis in rat testis was studied in detail to find out (i) spermatogenic stage or seminiferous epithelium region specific involvement of germ cells in apoptosis, (ii) preferential specificity of a particular germ cell type to become apoptotic and (iii) the ratio of live and dead testicular cells isolated in vitro after various period of ischaemic induction. Cell apoptosis, as observed in histological sections increased from 1 to 24 h of ischaemia. Apoptosis was not restricted to any specific germ cell type but was observed simultaneously in all the cell types in the initial hours (1-6 h) of ischaemia. No spermatogenic stage specific preference in apoptotic induction was also observed. However, as the duration of ischaemia progressed, the cell types observed to be most affected in number and morphology were the spermatids followed by spermatocytes. Centrally located tubules of testis were affected first than those located in the periphery. Overexpression of Bax staining was limited to few germ cell nuclei only. More than 95% of the germ cells in the control testis that earlier showed trypan blue dye exclusion were found stained after 12 h of ischaemia. Starting from early hours (1 h), lipid peroxidation rose proportionally with the duration of ischaemia while superoxide dismutase (SOD) and catalase activities were found decreased. Significant (p < 0.05) increase in the activities of glutathion-s-transferase and levels of hydrogen peroxide were observed after 6 h of ischaemia. These findings indicate that the physiological processes of oxidative stress have a direct linkage to the extent of germ cell apoptosis in the seminiferous epithelium.

Immunohistochemical localization of macrophage CD68+, HLA-DR+, L1+ and CD44+ subsets in uterine endometrium during different phases of menstrual cycle

Different tissue macrophage subsets were immunohistochemically examined in normal endometrial samples collected from proliferative (n=4), peri-ovulatory (n=6) and secretory (n=8) phases of menstrual cycles in women. The different macrophage subsets, namely CD68 (pan macrophage marker), CD44 (transmembrane adhesion molecule), HLA-DR (transmembrane heterodimeric protein involved in antigen presentation) and L1 (calprotectin)-positive cells, as well as, CD45 (common leucocytic antigen)-positive cells were examined on the basis of immunohistochemical staining, and areas of immunoprecipitation were analyzed morphometrically using computer-assisted video imaging system. The stage-specific distribution of receptors for estrogen (ER) and progesterone (PR) in endometrial cells were examined and morphometrically analyzed. There was an increase in the number of CD45+ cells (P < 0.01) and CD68+ cells (P < 0.05) in secretory phase endometrium compared with proliferative and peri-ovulatory phases. There was no remarkable cycle dependent pattern in HLA-DR+ and L1+ cells. However, there was an increase in CD44 immunopositive area in peri-ovulatory (P < 0.05) and in secretory (P < 0.01) phases of endometrium compared with proliferative phase endometrium. A higher (P < 0.01) degree of immunopositivity for ER was observed during peri-ovulatory phase, and for PR, during peri-ovulatory (P < 0.05) and secretory (P < 0.01) phases compared with proliferative phase of cycle. Positive correlations between areas occupied by (i) CD68+ cells and PR (P < 0.01), (ii) HLA-DR+ and L1+ cells (P < 0.05), (iii) CD45+ and CD68+ cells (P < 0.01), (iv) CD45+ and L1+ cells (P < 0.05), and (v) PR and L1+ cells (P < 0.05) were obtained. It appears that the recruitment of different macrophage subsets in human endometrium involves a complex set of endocrine and paracrine factors.

Antidiabetic effect of aqueous extract of seed of Tamarindus indica in streptozotocin-induced diabetic rats

In Indian traditional system of medicine, herbal remedies are prescribed for the treatment of diseases including diabetes mellitus. In recent years, plants are being effectively tried in a variety of pathophysiological states. Tamarindus indica Linn. is one of them. In the present study, aqueous extract of seed of Tamarindus indica Linn. was found to have potent antidiabetogenic activity that reduces blood sugar level in streptozotocin (STZ)-induced diabetic male rat. Supplementation of this aqueous extract by gavage at the dose of 80 mg/0.5 ml distilled water/100 g body weight per day in STZ-induced diabetic rat resulted a significant diminution of fasting blood sugar level after 7 days. Continuous supplementation of this extract for 14 days resulted no significant difference in this parameter from control level. Moreover, this supplementation produced a significant elevation in liver and skeletal muscle glycogen content, activity of liver glucose-6-phosphate dehydrogenase in respect to diabetic group. Activities of liver glucose-6-phosphatase, liver and kidney glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) activities were decreased significantly in the aqueous extract supplemented group in respect to diabetic group. All these parameters were not resettled to the controlled level after 7 days of this extract supplementation but after 14 days of this supplementation, all the above mentioned parameters were restored to the control level.

From disease genes to cellular pathways: a progress report

Mutations in a large number of retinal and retinal pigment epithelium (RPE) expressed genes can lead to the degeneration of photoreceptors and consequently the loss of vision. The genetic and phenotypic heterogeneity of retinal dystrophies poses a complex problem with respect to rational development of therapeutic strategies. Delineation of physiological functions of disease genes and identification of pathways that lead to disease pathogenesis represent essential goals towards developing a systematic and global approach to gene-based treatments. We are interested in identifying cellular pathways that are involved in photoreceptor differentiation, function and degeneration. We are, therefore, generating comprehensive gene expression profiles of retina and RPE of humans and mice using both cDNA- and oligonucleotide-based (Affymetrix) microarrays. Because of the under-representation of retinal/RPE genes in the public databases, we have constructed several unamplified cDNA libraries and produced almost twenty thousand expressed sequence tags (ESTs) that are being printed onto glass slides ('I-Gene' microarrays). In this presentation, we will report the microarray analysis of the rodless (and cone-enhanced) retina from the Nrl-knockout mouse as a paradigm to initiate the identification of cellular pathways involved in photoreceptor differentiation and function.

Analysis of genetic variability of Indian isolates of Hepatitis C virus

The degree of genetic variability among Hepatitis C virus strains circulating in India is currently unknown. In order to get insight into this matter, sequence data obtained from the 5' non coding region from 8 patients from New Delhi were compared with sequences from 16 HCV isolates from different geographic locations of India. The phylogenetic analysis of most prevalent genotypes revealed the presence of novel HCV variants in type 1 strains.

Endocrine and paracrine correlates of endometrial receptivity to blastocyst implantation in the human

Synchronous attainment of maternal endometrial receptivity allows implantation-stage adhesive blastocyst to undertake apposition, attachment and invasion. In the present essay, we propose a model according to which luteal phase progesterone induces a basic drive in endometrium toward receptivity and as a result, adequately primed endometrium differentiates through certain steps in a fixed action pattern. The implantation-stage embryo senses such endometrial responsiveness circumstantially by the factors secreted by maternal endometrium and undertakes differentiation to implant by secreting factors which act on maternal endometrial cells to further potentiate them to implantation stage-specific changes. Such a dynamic temporo-spatial manner of interaction involving a set of specific factors acting synchronously leads to the activation of innate releasing process in both compartments towards embryo attachment followed by successful intrusion and controlled invasion of trophoblast cells into maternal endometrium. In the present review we discuss the potential role of various endocrine and paracrine factors in the process of blastocyst implantation in the human.

Immunohistochemical localization of leukemia inhibitory factor, interleukins 1 and 6 at the primary implantation site in the rhesus monkey

Blastocyst implantation and placentation involve localized inflammatory type of responses at and around the site of nidation. In the present study, the likely involvement of inflammatory cytokines, namely, leukemia inhibitory factor (LIF), interleukins 1 alpha and 1 beta (IL-1alpha and IL-1beta) and IL-6 at the primary implantation site of the rhesus monkey was examined immunocytochemically during lacunar (n=6) and villous (n=8) stages of gestation. Trophoblast cells and extraembryonic mesenchymal cells were immunopositive for LIF and IL-1alpha. The distribution of IL-1beta and IL-6 in trophoblast cells was low in lacunar stage samples, however, a higher degree of immunopositivity for IL-6 was observed in villous stage samples. Decidual cells were immunopositive for all the cytokines studied. In lacunar stage samples, plaque cells adjacent to implanted nidus were immunopositive for all the cytokines examined, and the degree of their immunoprecipitation increased, except that of IL-1beta, during the villous stage. Luminal and glandular epithelial cells were immunopositive for LIF, IL-1alpha, IL-1beta and IL-6 in lacunar and in villous stage samples. LIF immunopositivity was detected in endothelial cells of blood vessels within and below chorionic plate and cytotrophoblast shell, while vascular smooth muscle cells were positive for all the cytokines studied. The temporo-spatial characteristics of LIF, IL-1alpha, IL-1beta and IL-6 protein expressions in primary implantation sites of the rhesus monkey suggest that these pro-inflammatory cytokines play specific roles in regulating trophoblast cell proliferation, differentiation, invasion and associated maternal tissue remodelling during early gestation.

A multiparametric study of the action of mifepristone used in emergency contraception using the Rhesus monkey as a primate model

Mifepristone is a potent agent used in emergency contraception (EC). In the present study, we examined the contraceptive efficacy of mifepristone used in EC and then, using the model of mifepristone-based EC, we investigated its mechanism of action in the rhesus monkey. Sexually mature females were allowed to cohabitate with male animals from 1600 to 900 h of any one day of days 8-17 of cycle without (Group I; n = 6) and with a single dose of mifepristone (Group II, n = 31, 25 mg per animal, subcutaneous) 72 h postcoitus. Blood samples from all animals of Groups I and II were used to determine the concentrations of estradiol (E), progesterone (P) and chorionic gonadotrophin in peripheral circulation for retrospective analysis of the days of ovulation and blastocyst implantation. Four out of six animals (66.6%) in Group I became pregnant, while all 31 monkeys in Group II failed to establish pregnancy along with marginal changes in serum concentrations of E and P. In the second part of the study, animals were subjected to the same experimental protocol followed by collection of endometrial tissue samples on cycle day 22 from animals of both Group I (n = 6) and Group II (n = 24). Endometrial samples were subjected to morphological analysis including mitotic index, immunohistochemistry for vascular endothelial growth factor (VEGF), leukemia inhibitory factor (LIF), transforming growth factor beta1, estradiol receptor (ER), progesterone receptor (PR), proliferating cell nuclear antigen, placental protein 14 (PP 14) and detection of apoptosis by terminal nick end labeling method followed by histometric analysis. The results were retrospectively analyzed between the two groups on the basis of the day of treatment after ovulation: early luteal phase (days 0-3 postovulation) and mid-luteal phase (days 4-7 after ovulation). Mifepristone used in EC in the present study resulted in general loss of functional integrity of epithelial compartment characterized by loss of secretory maturation, increased apoptosis and higher degree of degeneration along with decreased expression of VEGF, LIF, PP14 and ER, while PR level increased as compared to control samples. The vascular compartment appeared to be compromised along with affected morphological features and decreased expression of VEGF, LIF, ER and PR following the administration of mifepristone. It appears that mifepristone used in EC alters the physiological homeostasis in epithelial and vascular compartments of implantation stage endometrium rendering it hostile to blastocyst implantation. Furthermore, the degree to which the endometrial function is affected largely depends on the day of mifepristone treatment in a parameter-specific manner resulting in a higher degree of degenerative changes in samples obtained from animals who received mifepristone during mid-luteal phase of cycles.

Effect of Stephania hernandifolia leaf extract on testicular activity in rats

AIM

The testicular inhibitory effect of the aqueous fraction of methanol extract of Stephania hernandifolia leaf was studied in male Wistar rats.

METHODS

The supernatent and the precipitate part of aqueous fractions of the methanol extract of the leaf were gavaged separately to rat at a similar dose of 200 mg/mL per 100 g body weight per day for 28 days. After cessation of treatment, various observations were conducted.

RESULTS

In both treated groups, there were significant decreases in the relative weights of the sex organs, the testicular key androgenic enzymes activities, the plasma level of testosterone, the number of different germ cells at stage VII of seminiferous epithelial cell cycle and the seminiferous tubular diameter in comparison to the controls. Neither of the parts had somatic, renal and hepatic toxicity. This study suggested that the active molecules present in the aqueous fraction of methanol extract of Stephania hernandifolia leaves might be steroids as indicated by thin layer chromatography using specific staining substance for steroid molecules.

CONCLUSION

In rats, the aqueous fraction of methanol extract of the S. hernandifolia leaves possesses certain testis-inhibitory substances, which may be steroid-like agents.

Effect of early luteal phase administration of a single dose mifepristone on immunohistochemical distribution of interleukin 1 alpha (IL-1 alpha) and transforming growth factor beta 1 (TGF-beta 1) in mid-luteal phase ovary of the rhesus monkey

A single low dose administration of a high affinity anti-progestin agent like mifepristone during the early luteal phase inhibits blastocyst implantation in human and non-human primates. Though it has been observed that luteal phase serum concentrations of estradiol and progesterone were not affected by the application of anti-nidatory dose of early luteal phase mifepristone suggesting that ovarian steroidogenic function is not compromised, it is nevertheless possible that ovarian physiology at the local tissue level is affected in this treatment schedule. In the present study, healthy, mature, proven fertile female rhesus monkeys were divided into two groups. Group 2 animals were treated with a single dose of mifepristone (2 mg/kg body weight), while group 1 animals were injected with vehicle (1:4 benzoyl benzoate: olive oil, v/v, s.c.) on day 2 post-ovulation. The morphological examination including that of vascularity, as well as, histometric determination of profiles of immunopositivity for IL-1alpha and TGF-beta1 in stromal, follicular and luteal compartments of mid-luteal phase ovaries from animals with or without a single, anti-nidatory dose of mifepristone applied on day 2 after ovulation failed to reveal any significant change between the two groups. Thus, it appears that early luteal phase administration of a single antinidatory dose of mifepristone does not affect the ovarian physiology in the treatment cycle.

Experimental models for human implantation

An understanding of the cellular and molecular basis of blastocyst implantation in the human remains as yet a black box, however, a few experimental models using human and non-human primate species have addressed this issue. This review attempts to highlight, based on experimental evidence, the paradigm shifts in our understanding of the endocrine basis of embryo implantation, and the nature of dialogue between a growing, viable conceptus and maternal endometrial cells in the establishment of 'receptivity' for blastocyst implantation. It is being proposed that an existing inflammation paradigm of blastocyst implantation could be tested using an experimental model to compare tissue behaviour of conceptus associated endometrial cells with that occurring after induction of deciduoma in hormone-primed uterus. We anticipate that an in vitro model of blastocyst implantation using the experimental models of homotypic and heterotypic cultures of uterine epithelial and stromal fibroblast cells expressing structural and functional phenotypic responses as observed in situ may provide us with necessary clues about the temporal and spatial nature of cellular and molecular functions involving various endocrine and paracrine factors at implantation.

Activation of early signaling transcription factor, NF-kappaB following low-level manganese exposure

Occupational and environmental exposure to manganese (Mn(2+)) is an increasing problem. It manifests neuronal degeneration characterized by dyskinesia resembling Parkinson's disease. The study was performed to test the hypotheses whether exposure to Mn(2+) alters cellular physiology and promotes intracellular signaling mechanism in dopaminergic neuronal cell line. Since transcription factors have been shown to play an essential role in the control of cellular proliferation and survival, catecholaminergic rich pheochromocytoma (PC12) cells were used to measure changes in the DNA binding activities of nuclear factor kappa B (NF-kappaB) by electrophoretic mobility shift assay (EMSA) following Mn(2+) (0.1-10 microM) exposure. Cells that were exposed to Mn(2+) produced five-fold-activation of transcription factor NF-kappaB DNA binding activity. This remarkable increase was seen within 30-60 min period of Mn(2+) exposure. Activation of NF-kappaB DNA binding activity by Mn(2+) at 1.0 microM correlated with proteolytic degradation of the inhibitory subunit IkappaB(alpha) as evidenced in cytosol. Additional experiments on NF-kappaB reporter gene assay also showed increased NF-kappaB gene expression at 1.0 and 5.0 microM Mn(2+) and this was completely blocked in the presence of NF-kappaB translocation inhibitor, IkappaB(alpha)-DN supporting that NF-kappaB induction occurred during Mn(2+) exposure. In addition, Mn(2+) exposure to PC 12 cells led to activation of signal responsive mitogen activated protein kinase kinase (MAPKK). These results suggest that Mn(2+) at a low dose appears to induce the expression of immediate early gene, NF-kappaB through MAPKK by a mechanism in which IkappaB(alpha) phosphorylation may be involved.

Dose-dependent response to an intratesticular injection of calcium chloride for induction of chemosterilization in adult albino rats

This study concerned the minimum and optimum effective doses of calcium chloride needed for induction of chemosterilization in male albino rats, 30 days after a single intratesticular injection of calcium chloride (CaCl2.2H2O) solution at 2.5, 5, 10 or 20 mg per 100 g body weight per testis. There was a significant diminution in the relative wet weight of the sex organs (p<0.01), epididymal sperm count (p<0.001), plasma concentration of testosterone (p<0.01), testicular activities of delta5,3beta-hydroxy steroid dehydrogenase (delta5,3beta-HSD), 17beta-hydroxy steroid dehydrogenase (17beta-HSD) (p<0.01), glutathione S-transferase (GST) (p<0.01), superoxide dismutase (SOD) (p<0.01), and peroxidase (p<0.01), significant elevations in testicular content of malondialdehyde (MDA) and conjugated dienes (p<0.01), along with derangement of seminiferous tubular architecture and degeneration of the Leydig cells in the testis and elevations in the concentrations in the plasma of LH and FSH (p<0.01), commencing at a dose of 5 mg, with the greatest effects at a dose of 20 mg. No significant alterations in these factors occurred at the dose of 2.5 mg in comparison to the control that received only the vehicle. There was no significant alteration in the plasma concentrations of prolactin (p>0.05), corticosterone (p>0.05) or fasting blood glucose or in the rectal temperature (p>0.05) at any of the doses relative to the control group, suggesting that this chemosterilizing procedure did not exert any chronic stress on the experimental animals. From these observations, it may be suggested that 5 mg should be considered as the minimum dose, and 10 mg or 20 mg as the optimum dose, whereas 2.5 mg was ineffective for induction of chemosterilization. There would seem to be little point in using more than 20 mg of calcium chloride for this purpose. Intratesticular injection of calcium chloride at an effective dose may be considered as an alternative to surgical castration.

Foodborne outbreak caused by a Norwalk-like virus in India

An outbreak of acute gastroenteritis occurred in the nurses' hostel of a civil hospital in Delhi, after a farewell party involving 130 nurses and some of the housekeeping staff. All affected persons had eaten salad sandwiches at the party. Stool samples were collected from six of these patients on the second day of infection. All six samples, when tested for the presence of common bacteria, parasites, and rotavirus, were found to be negative. The clinical features of this outbreak matched the criteria set for outbreaks caused by Norwalk-like viruses (NLVs). Reverse transcription-polymerase chain reaction (RT-PCR) was carried out on these six samples, using primers from the RNA-dependent RNA polymerase (RdRp) gene of NLVs. Immunoelectron microscopy was carried out on two of the samples, using convalescent phase serum. All six samples were positive for genogroup (GG) II NLVs by RT-nested PCR. Aggregates of 32-nm viral particles were visualized by immunoelectron microscopy in one of the two samples. Sequencing of the RdRp gene was done on amplicons from three samples; phylogenetic analysis placed the isolates NDV/1999 in a Toronto virus cluster of GG II NLVs. This is the first report of a food-borne outbreak attributable to NLVs from India.

Partial VP1/2A gene sequence based molecular epidemiology of wild type 1 poliovirus isolates from some parts of India

Genomic variability within the sequences of VP1/2A junction among polioviruses from across the globe has revealed the existence of several endemic genotypes and their epidemiological inter-relationships; but such data on Indian isolates are scanty. The present work was intended to ascertain the persistence and transmission pattern of different genotypes of wild type 1 polioviruses circulating in India. Forty-eight wild type 1 poliovirus isolates obtained from different parts of India during 1996-8 were subjected to RT-PCR and nucleotide sequencing using M13 tailed primers. A 293 base pair region was amplified and sequenced for genetic variation study. Considering the 15% divergence of the sequences from Sabin 1, the isolates from six different states of India confirmed a single dominant genotype 4. Phylogenetic analysis revealed the circulation and active inter-state transmission of many genetically distinct strains of wild poliovirus type 1 belonging to genotype 4. This warrants the need for insisting on more efficient surveillance mechanisms so as to assess the impact of an extensive pulse polio immunization programme in India.

Testicular gametogenic and steroidogenic activities in cyclophosphamide treated rat: a correlative study with testicular oxidative stress

The present work examined the changes in testicular activities in relation to testicular oxidative stress in cyclophosphamide as well as human chorionic gonadotrophin (hCG) co-treated cyclophosphamide treated Wistar strain rats. Testicular activities were evaluated by the quantification of spermatogenesis and by the measurement of steroidogenic key enzyme activities along with plasma levels of testosterone. Testicular oxidative stress in relation to cyclophosphamide treatment was monitored by the study of products of free radicals like conjugated dienes and malondialdehyde (MDA) as well as the activity of testicular antioxidant enzymes like peroxidase and catalase. Cyclophosphamide treatment at the dose of 5 mg/kg body weight/day for 28 days resulted a significant diminution in the activities of testicular delta 5, 3 beta-hydroxysteroid dehydrogenase (delta 5, 3 beta-HSD), 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) activities, plasma level of testosterone along with significant reduction in the number of germ cells at stage-VII of spermatogenesis. Levels of testicular MDA and conjugated dienes both were elevated whereas testicular peroxidase and catalase activities both were inhibited significantly in cyclophosphamide treated rats in comparison to control. After hCG co-administration at the dose of 5 I.U./kg body weight/day for 28 days in cyclophosphamide treated rats resulted a significant protection in the activities of testicular peroxidase and catalase along with significant decrease in the levels of MDA and conjugated dienes to the control level. Moreover, the testicular steroidogenic key enzyme activities and spermatogenesis along with plasma levels of testosterone were restored to the control level. Therefore, it may be concluded that there is a correlation between testicular steroidogenic activities as well as spermatogenesis and testicular oxidative stress in cyclophosphamide treated rats. Moreover, as restoration of plasma testosterone to the control level is noted in hCG co-treated cyclophosphamide treated rat, therefore, the results suggest that testosterone may be the key regulator for this correlation.

Testicular toxicity in sodium fluoride treated rats: association with oxidative stress

This study examined the effect of sodium fluoride, a water pollutant important through the world, including India, on testicular steroidogenic and gametogenic activities in relation to testicular oxidative stress in rats. Sodium fluoride treatment at 20mg/kg/day for 29 days by oral gavage resulted in significant diminution in the relative wet weight of the testis, prostate, and seminal vesicle without alteration in the body weight gain. Testicular delta(5),3beta-hydroxysteroid dehydrogenase (HSD) and 17beta-HSD activities were decreased significantly along with significant diminution in plasma levels of testosterone in the fluoride-exposed group compared to the control. Epididymal sperm count was decreased significantly in the fluoride-treated group and qualitative examination of testicular sections revealed fewer mature luminal spermatozoa in comparison to the control. The seminiferous tubules were dilated in treated animals. Fluoride treatment was associated with oxidative stress as indicated by an increased level of conjugated dienes in the testis, epididymis, and epididymal sperm pellet with respect to control. Peroxidase and catalase activities in the sperm pellet were decreased significantly in comparison to the control. The results of this experiment indicate that fluoride at a dose encountered in drinking water in contaminated areas exerts an adverse effect on the male reproductive system and this effect is associated with indicators of oxidative stress.