Transgenerational effects of maternal exposure to nicotine on structures of pituitary-gonadal axis of rats.

Smoking can lead to several diseases and cause a reduction in fertility in men and women. Among the various components of cigarettes harmful during pregnancy, nicotine stands out. It can cause a reduction in placental blood flow, compromising the development of the baby with neurological, reproductive and endocrine consequences. Thus, we aimed to evaluate the effects of nicotine on the pituitary-gonadal axis of rats exposed during pregnancy and breastfeeding (1st generation - F1), and whether the possible damage observed would reach the 2nd generation (F2). Pregnant Wistar rats received 2 mg/kg/day of nicotine throughout the entire gestation and lactation. Part of the offspring was evaluated on the first neonatal day (F1) for macroscopic, histopathological and immunohistochemical analyses of brain and gonads. Another part of the offspring was kept until 90 days-old for mating and obtainment of progenies that had the same parameters evaluated at the end of pregnancy (F2). The occurrence of malformations was more frequent and diversified in nicotine-exposed F2. Brain alterations, including reduced size and changes in cell proliferation and death, were seen in both generations of nicotine-exposed rats. Male and female gonads of F1 exposed rats were also affected. The F2 rats showed reduced cellular proliferation and increased cell death on the pituitary and ovaries, besides increased anogenital distance in females. The number of mast cells was not enough altered to indicate an inflammatory process in brain and gonads. We conclude that prenatal exposure to nicotine causes transgenerational alterations in the structures of pituitary-gonadal axis in rats.

Does maternal exposure to nicotine affect the oocyte quality and reproductive capacity in adult offspring?

Gonadal development begins in the intrauterine phase and females from most species are born with an established oocyte reserve. Exposure to drugs during gestation can compromise the offspring health, also affecting the gametes quality. Nicotine, the main component of cigarettes, is an oxidant agent capable of altering the fertility in men and women. As female gametes are susceptible to oxidative stress, this drug can damage the oolemma and affect oocyte maturation, induce errors during chromosomal segregation and DNA fragmentation. Oocyte mitochondria are particularly susceptible to injuries, contributing to the oocyte quality loss and embryonic development disruption. Thus, considering the high number of women who smoke during pregnancy, while significant events are occurring in the embryo for future fertility of offspring, we seek to verify the quality of the oocytes from adult rats exposed to nicotine during intrauterine phase and breastfeeding. Pregnant Wistar rats received nicotine by osmotic mini-pumps and the female progenies were evaluated in adulthood for oocyte quality (viability, lipid peroxidation, generation of reactive oxygen species and mitochondrial integrity) and reproductive capacity. Embryos (3dpc) and fetuses (20dpc) generated by these rats were also evaluated. The results showed that the dose of 2 mg/kg/day of nicotine through placenta and breast milk does not affect the number of oocytes and the fertility capacity of adult rats. However, it causes some morphological alterations in oocytes, mitochondrial changes, embryonic fragmentation and disruption of fetal development. The malformations in fetuses generated from these gametes can also indicate the occurrence of epigenetic modifications.

Dengue outbreaks: unpredictable incidence time series.

Dengue fever is a disease with increasing incidence, now occurring in some regions which were not previously affected. Ribeirão Preto and São Paulo, municipalities in São Paulo state, Brazil, have been highlighted due to the high dengue incidences especially after 2009 and 2013. Therefore, the current study aims to analyse the temporal behaviour of dengue cases in the both municipalities and forecast the number of disease cases in the out-of-sample period, using time series models, especially SARIMA model. We fitted SARIMA models, which satisfactorily meet the dengue incidence data collected in the municipalities of Ribeirão Preto and São Paulo. However, the out-of-sample forecast confidence intervals are very wide and this fact is usually omitted in several papers. Despite the high variability, health services can use these models in order to anticipate disease scenarios, however, one should interpret with prudence since the magnitude of the epidemic may be underestimated.

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 (ß-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 ß-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.

Liver steatosis in celiac disease: the open door.

Non-alcoholic fatty liver disease (NAFLD) is a common disease of unknown origin characterized by histological features similar to alcoholic-like liver injury but in the absence of significant alcohol intake. Non-alcoholic fatty liver disease refers to a spectrum of diseases of the liver ranging from simple steatosis (i.e., fatty infiltration of the liver) to nonalcoholic steatohepatitis (i.e., steatosis with inflammation and hepatocyte necrosis) to cirrhosis. Non-alcoholic fatty liver disease is frequently associated with disorders such as insulin resistance, obesity, type 2 diabetes mellitus, hyperlipidemia and protein-calorie malnutrition. However, in a subgroup of NAFLD patients, the true relevant cause remains undetermined. Celiac disease (CD) is a common immune-mediated disorder and develops in genetically susceptible subjects after the ingestion of gluten proteins. Celiac disease has been found in about 10% of patients with unexplained abnormal liver tests, and in about 3.5% of patients with NAFLD as the only manifestation of the disease. The frequency of subclinical or silent presentations in older children and adults highlights the importance of CD screening in patients with unexplained chronic abnormal liver function tests and NAFLD without any specific etiology. The pathogenesis of liver steatosis in CD is uncertain. The aims of this review are to describe the possible mechanisms involved in the occurrence and progression of liver steatosis in CD patients.

Amifostine-doxorubicin association causes long-term prepubertal spermatogonia DNA damage and early developmental arrest.

BACKGROUND: In a previous study, we found that amifostine provides some protection to the seminiferous epithelium of prepubertal doxorubicin-treated male rats but does not improve their fertility status as adults. Based on these results, a long-term study was undertaken to evaluate the DNA damage caused to spermatogonia and the consequences for embryo development. METHODS: Twenty-four male prepubertal rats (30-day-old) were divided into four equal groups and treated with: doxorubicin (D--5 mg/kg), amifostine (A--400 mg/kg), amifostine/doxorubicin (AD--amifostine 15 min before doxorubicin) and control (C--0.9% saline solution). Sixty-four days after the treatment, animals were euthanized and the testes and epididymides were excised. The testes were fixed in Bouin's solution and historesin-embedded for histopathological analysis. Spermatozoa from the cauda epididymides were collected for chromatin structure analyses (Comet Assay and SCSA™). Adult rats (100-day-old) were mated with fertile females for embryo analyses on 2.5, 4.5 and 20 days post-coitum (d.p.c.). RESULTS: The seminiferous epithelium histopathology of AD group was better preserved compared with the D group. On the other hand, rats from the D and AD groups presented an increased percentage of sperm DNA strand breaks, as assessed by the comet assay, as well as an increased level of sperm chromatin denaturation, as assessed by the SCSA™ assay. In amifostine-treated groups (A and AD) there was a significant increase in the number of arrested embryos, as observed by the number of oocytes/zygotes on 2.5 d.p.c., when compared with control and doxorubicin groups; however, this number was increased when the AD group was compared with the A group. CONCLUSIONS: These results raise a concern about the effects of the association of these two drugs on the germ cell genome. Amifostine-doxorubicin-exposed rat spermatogonia produced long-term damage on sperm DNA, compromised conceptus development and reduced pregnancy outcome.

Carnitine partially improves oxidative stress, acrosome integrity, and reproductive competence in doxorubicin-treated rats.

Doxorubicin has been largely used in anticancer therapy in adults, adolescents, and children. The efficacy of l-carnitine as an antioxidant substance has been confirmed both in humans and rats. Carnitine, present in testis and epididymis, is involved in sperm maturation. It is also effective in infertility treatment. As a continuation of a previous study, we evaluated whether some spermatic qualitative parameters, DNA integrity, chromatin structure, and fertility status, could be ameliorated by the carnitine treatment in adult rats, which were subsequently exposed to doxorubicin at pre-puberty. Pre-pubertal male rats were distributed into four groups: Sham Control; Doxorubicin; l-carnitine; l-carnitine + Doxorubicin (l-carnitine injected 1 h before doxorubicin). At 100 days of age, all groups were reassigned into two sets: One set was submitted to the evaluation of sperm motility, acrosome integrity, mitochondrial activity, sperm chromatin structure analysis (SCSA), and evaluation of the oxidative stress. The other set of rats was destined to the evaluation of reproductive competence. The percentage of spermatozoa with intact acrosome integrity was higher in the Carnitine+Doxorubicin group when compared with the Doxorubicin group. However, sperm motility and mitochondrial activity were not improved by carnitine pre-treatment. Both values of malondialdehyde and nitrite (indirect measurement of nitric oxide) concentrations were statistically higher in the only doxorubicin-treated group when compared to the Carnitine + Doxorubicin group. Fertility index and implantation rate were lower in Doxorubicin group, when compared to Carnitine + Doxorubicin group. Moreover, the percentage of spermatozoa with damaged DNA was higher in the Doxorubicin-treated group when compared to the Carnitine+Doxorubicin group. l-carnitine, when administered before doxorubicin, partially preserved the acrosome integrity, an important feature related to sperm fertilization ability that positively correlated with the reproductive competence and sperm DNA integrity at adulthood. In conclusion, l-carnitine attenuated the long-term alterations caused by doxorubicin in the germ cells and improved male reproductive capacity in adulthood.

Late reproductive analysis in rat male offspring exposed to nicotine during pregnancy and lactation.

We previously observed that nicotine, administered to rats (Wistar) during pregnancy and lactation periods, provokes, in the progeny, late morphofunctional alterations in Leydig cell, body weight increase in adulthood (90 days post partum, dpp) as well as seminiferous epithelium injury. Aiming to investigate whether the spermatogenic damage previously observed in adult progenies from pregnant and lactating nicotine-exposed rat dams are maintained or whether it is worsened in older rats, we analyzed the morphological testicular alterations after up to two complete periods of spermatogenesis (53 days each), spermatic parameters, and sperm DNA fragmentation. Pregnant and lactating rats were nicotine-exposed (2 mg/kg/day) through an osmotic minipump implanted on the first day of pregnancy and replaced after birth. Absolute Control (no minipump) and Sham Control (minipump without nicotine) groups were established. The offspring were killed at 90, 143, and 196 dpp. Significant alterations in morphometric and stereological testicular parameters, such as concentration of sperm number, daily sperm production, and plasma and intratesticular levels of cholesterol and testosterone were not observed in nicotine-exposed rats. Testicular histopathological analysis showed small intraepithelial vacuolization and an accentuated germ cell desquamation in exposed rats. However, the offspring from nicotine-exposed dams exhibited higher frequency of morphologically abnormal spermatozoa and lower sperm motility in comparison with control groups. In addition, nicotine-exposed groups showed a significant reduction in sperm mitochondrial activity and an increased sperm DNA fragmentation (Comet assay). These results indicate a late reproductive damage in the male progeny caused by maternal nicotine exposure, related to the decrease in sperm quality.

Characterization of the membrane-associating domain of the sperm adhesive protein, bindin.

Bindin is an adhesive protein that mediates the binding of sea urchin sperm to the egg during fertilization. Bindin selectively associates with gel-phase phospholipid vesicles in a peripheral fashion. Bindin interacts specifically with sulfated fucan on the egg's surface, and directly with the phospholipid bilayer of the sperm. Analysis of a series of deletion mutants of recombinant bindin was undertaken to define the membrane associating domain of bindin. Recombinant and sperm bindin display nearly identical binding kinetics to gel-phase phospholipids and have equivalent saturation points of approx. 250 lipid molecules per molecule of bindin. Deletion mutants of bindin which contain residues 75-130 retained specific membrane binding activity. Synthetic peptides corresponding to residues 69-130, and 92-130 also display gel-phase specific membrane association. This region is highly conserved within four different species of bindin molecules. Circular dichroism spectroscopy of synthetic peptides corresponding to residues 92-130 and 69-130 suggests that a distinct change in conformation takes place upon binding liposomes. Taken together, these data indicate that the membrane binding activity of bindin residues within this highly conserved region of the bindin molecule.

Intrauterine food restriction as a determinant of nephrosclerosis.

We previously showed that 3-month-old rats subjected to a 50% intrauterine food restriction had a decreased number of nephrons with increased glomerular diameter, which suggests compensatory hypertrophy. Hypertrophy could be the early event of glomerular damage. In this study, we extended our investigation and performed functional, morphological, and immunohistochemical evaluations in 3- and 18-month-old rats that underwent a 50% intrauterine food restriction (RT3 and RT18, respectively) and age-matched control rats (C3 and C18, respectively). Our findings showed that glomerular filtration rate was significant decreased in RT18 rats (2.42 +/- 0.15 mL/min/kg; n = 28; P: < 0.05) compared with C18 control rats (4.19 +/- 0.10 mL/min/kg; P: < 0.05) and the percentage of glomeruli with sclerosis was greater in RT18 rats (13.01% +/- 2.95%; n = 9; P: < 0.01) than in C18 rats (2.71% +/- 0.35%; n = 6). RT18 rats also showed more intense tubulointerstitial lesions and immunohistochemical alterations in the renal cortex. Immunohistochemical studies showed increased fibronectin and desmin expression in glomeruli and tubulointerstitium and increased vimentin and alpha-smooth muscle actin in the tubulointerstitial area from the renal cortex of RT18 rats (P: < 0.05). Desmin was also increased at the edge of glomeruli from RT18 rats, suggesting podocyte injury. Our data show that when food restriction is imposed during pregnancy, permanent damage occurs in the kidney of the offspring. Glomerular lesions were more severe than the tubulointerstitial damage in these animals.

Air pollution and child mortality: a time-series study in São Paulo, Brazil.

Although most available evidence relating air pollution and mortality was obtained for adults, pollution has been also associated with increased mortality in children, but in a significantly smaller number of studies. This study was designed to evaluate the association between child mortality and air pollution in the city of São Paulo, Brazil, from 1994 to 1997. Daily records of mortality due to respiratory diseases for children under 5 years of age were obtained from the municipal mortality information improvement program. Daily concentrations of sulfur dioxide (SO(2)), carbon monoxide (CO), inhalable particulate matter less than 10 microm in diameter (PM(10)), and ozone were obtained from the state air pollution controlling agency. Information on minimum daily temperature and on relative humidity were obtained from the Institute of Astronomy and Geophysics of the University of São Paulo. Statistical analysis was performed through generalized additive models considering a Poisson response distribution and a log link. Explanatory variables were time, temperature, humidity, and pollutant concentrations. The loess smoother was applied to time (in order to model seasonality) and temperature. Significant associations between mortality and concentrations of CO, SO(2), and PM(10) were detected. The coefficients (and standard errors) of these three pollutants were 0.0306 (0.0076), 0.0055 (0.0016), and 0.0014 (0.0006), respectively. The observed associations were dose dependent and quite evident after a short period of exposure (2 days). According to the proposed model and considering the mean of the pollutant concentration during the period of the study, the estimated proportions of respiratory deaths attributed to CO, SO(2), and PM(10), when considered individually, are around 15, 13, and 7%, respectively.

In situ demonstration of both TUNEL-labeled germ cell and Sertoli cell in the cimetidine-treated rats.

Cimetidine has caused dysfunction in the male reproductive system. In the rat testis, intratubular alterations and loss of peritubular tissue due to peritubular myoid cell death by apoptosis have been recently shown. Thus, the aim of this study is to evaluate which cells of the seminiferous epithelium have been affected and/or died by apoptosis after the treatment with cimetidine. For this purpose, an experimental group containing five male albino Wistar rats received intraperitoneal injections of cimetidine (50 mg/kg body weight) during 52 days. The testes were fixed with 4% buffered formaldehyde and were embedded in paraffin. For detection of DNA breaks (apoptosis) in the cells of the seminiferous epithelium, the testicular sections were treated by the TUNEL method (Apop-Tag Plus Peroxidase Kit). In the tubules affected by cimetidine, altered peritubular tissue, including the presence of TUNEL labeling in the myoid peritubular cells, were usually found. In these tubules, the seminiferous epithelium exhibited low density of germ cells and TUNEL-positive labeling in the germ cells of the basal compartment. The concomitant staining in both germ cells of the basal compartment and late spermatids suggest a sensitivity of these cells in the damaged tubules. Besides germ cells, TUNEL-positive Sertoli cells were also found in the injured seminiferous tubules. Thus, a relationship between dying germ cells and Sertoli cell damage and/or death must be considered in tubules where peritubular tissue has been affected by toxicants.

Histomorphometry of immature rat testis after heating.

The scrotal testes of albino rats aged 35 and 45 days were immersed in water at constant temperatures of 43 degrees C, 44 degrees C, or 45 degrees C for periods of 15-45 min in a special heating device. At an age of 60 days, the rats were mated in individual cages with two primiparous rats each. At an age of 90 days, they were killed and their testes were histologically processed. Rats with testes that had been subjected to heating when the animals were 45 days old showed both alterations of the seminiferous tubules and a decrease in fertilizing capacity. The effect of heat was greater in animals at 45 than at 35 days of age. In heat-treated testes, tubules contained PAS-positive concretion, sometimes engulfed by macrophage-derived giant cells and multinucleate cells derived from spermatids that failed to separate during spermiogenesis. The decrease in testicular volume observed after heat treatment was due mainly to reduced parenchymal volume. Thermic lability of seminiferous stem cells increases with age until adulthood, and recovery from heat injury declines.

Combined regional and systemic chemotherapy by a mini-invasive approach for the treatment of colorectal liver metastases.

From February 1996 to December 1998, 95 patients affected with colorectal liver metastases underwent the positioning of an intraarterial hepatic catheter by a transcutaneous subclavian access, under local anesthesia. All patients were evaluated for catheter implantation complications. Moreover, 61 patients of 95 treated at our center were retrospectively evaluated for results of chemotherapy performed with two different schedules of hepatic artery infusion (HAI) combined with systemic chemotherapy (SC). Eleven patients (group A) were treated with combined SC (5-fluorouracil continuous infusion) and HAI (floxuridine). A subsequent 50 patients underwent HAI (floxuridine, 4 cycles) followed, if a response or stable disease were observed, by combined SC and HAI (group B). Three cases of aneurysm of subclavian artery occurred, which were treated by the positioning of a radiologic arterial stent and the reimplantation of the catheter by a femoral access. Thrombosis of the hepatic artery was registered in four cases. We observed 10.5% occurrence of dislocation of the catheter, which was always moved again in the hepatic artery. In group A, with 45% clinical objective response rate and 10% stable disease rate, median survival time and median time to extrahepatic progression were 9 and 6 months, respectively. In group B, we observed 44% clinical objective responses and 26% stable disease after HAI. Patients without disease progression and therefore submitted to sequential SC and HAI had a median survival time of 21 months and a median time to extrahepatic progression of 16 months. The development of the mini-invasive technique of implantation of an arterial port can avoid laparotomy for HAI. Percutaneous implantation of an arterial port has a low rate of technical complications. HAI followed by combined systemic and regional chemotherapy has good results in terms of survival and time to extrahepatic progression.

Function and morphometric evaluation of intrauterine undernutrition on kidney development of the progeny.

Renal function and renal morphometry of the progeny of rats submitted to 50% dietary restriction (pair-fed with control group) throughout pregnancy (RT group), during the first half of pregnancy (R1 group) or during the second half of pregnancy (R2 group) were studied 3 months after birth. Glomerular filtration rate (GFR) and renal plasma flow (RPF) decreased significantly in all groups when compared to control (C) (GFR, 4.44 +/- 0.12, 4.04 +/- 0.18, and 4.00 +/- 0.16 vs 6.87 +/- 0.17, and RPF, 19.06 +/- 0.57, 17.00 +/- 1.14, and 13.31 +/- 0.50 vs 22.57 +/- 0.67, respectively). Urinary osmolality tended to be lower in the R2 and RT groups (877.1 +/- 42.36 and 868.0 +/- 42.36 vs 975.1 +/- 38.31 in C), and the net acid excretion calculated per ml of GFR was either maintained or stimulated (R1 group). A significant decline in the number of glomeruli occurred in R1, R2 and RT rats (79.84 +/- 2.08, 62.30 +/- 2.07, and 58.16 +/- 2.31 vs 99.77 +/- 2.28 in C respectively). The results show that intrauterine undernutrition actually caused a deleterious effect on the number of functional nephrons.

Environmental epidemiology applied to urban atmospheric pollution: a contribution from the Experimental Air Pollution Laboratory (LPAE).

Systematic investigation on the effects of human exposure to environmental pollution using scientific methodology only began in the 20th century as a consequence of several environmental accidents followed by an unexpected mortality increase above expected mortality and as a result of observational epidemiological and toxicological studies conducted on animals in developed countries. This article reports the experience of the Experimental Air Pollution Laboratory at the School of Medicine, University of São Paulo, concerning the respiratory system and pathophysiological mechanisms involved in responses to exposure to pollution using toxicological and experimental procedures, complemented by observational epidemiological studies conducted in the city of São Paulo. It also describes these epidemiological studies, pointing out that air pollution is harmful to public health, not only among susceptible groups but also in the general population, even when the concentration of pollutants is below the limits set by environmental legislation. The study provides valuable information to support the political and economic decision-making processes aimed at preserving the environment and enhancing quality of life.

[Two cases of melanoma metastasis. Description and review of the literature]. / Due casi di metastatizzazione di melanoma. Descrizione e revisione della letteratura.

The metastases of malignant melanoma can appear after many years to primitive diagnosis and can involve many organs. There are reported two cases of metastatic melanoma presenting in a parotid gland and in the small bowel. The rarity of the metastatic melanoma to parotid gland and the difficulty of diagnosing intestinal involvement are discussed together with a review of the literature. The surgical treatment was justified by therapeutic and diagnostic aim, without positive influence on survival.

Reproductive function of the male obese Zucker rats: alteration in sperm production and sperm DNA damage.

Obesity has been considered a public health issue in many countries and is of increasing concern for authorities over the past 6 years. The Zucker rat is a good experimental model for obesity and diabetes studies due to its metabolic characteristics that are similar to those developed by humans. A total of 12 obese Zucker rats and their lean littermates were killed in pubertal and young adult phases for assessing organ weights (testis and epididymis), testicular histomorphometric and stereological analyses, daily sperm production, and transit time in the epididymis. Sperm integrity was also investigated in the adult animals using the Comet assay. Alterations in organ weights, seminiferous epithelium architecture, sperm production, and transit time were noticed in the pubertal fatty rats. The volume density of the lymphatic space was decreased in both the ages. Adult animals had a significant increase in the extent of damage found in sperm DNA. Our results show for the first time that leptin receptor deficiency compromises sperm production during puberty and that genetic obese Zucker rats have increased sperm DNA fragmentation.

Carnitine partially protects the rat testis against the late damage produced by doxorubicin administered during pre-puberty.

Doxorubicin, an anticancer drug, is widely included in chemotherapy protocols to combat childhood cancer. Carnitine, an important quaternary amine, is present in testis and epididymis and is involved in sperm maturation; it has been used in infertility treatment. In a previous study, our group observed that L-carnitine given before etoposide, another chemotherapeutic drug, reduces the spermatogenic damage and protects germ cells against apoptosis. This study aimed to evaluate the antiapoptotic and cytoprotective actions of L-carnitine in long- and mid-term basis, on the seminiferous epithelium of doxorubicin-treated pre-pubertal rats. Forty-eight 30-day-old male Wistar rats were distributed into four groups: sham-control; doxorubicin; carnitine; carnitine/doxorubicin (L-carnitine injected 1 h before doxorubicin). The rats were submitted to euthanasia at 64 and 100 days of age and their testes were collected for biometric, morphometric, and histopathological analyses. The numerical density of apoptotic germ cells was obtained (TUNEL method). In adult phase (100 days), the following spermatic parameters were analyzed: mature spermatid (19 step) count and sperm daily production per testis; sperm number and transit time through the epididymal caput/corpus and cauda; frequency of morphologically abnormal spermatozoa (from epididymal fluid), as well as sperm DNA integrity (Comet assay). The testicular and spermatic parameters at both ages were improved in rats treated with carnitine before doxorubicin. At 64 days, the TUNEL-positive germ cell frequency was lower in the carnitine/doxorubicin-treated rats comparatively to the doxorubicin-treated rats. At 100 days of age, the sperm DNA fragmentation was also lower in the previously carnitine-treated rats, as evidenced by the analysis of three parameters. Carnitine reduced the late testicular and spermatic damages caused by doxorubicin, probably providing a partial cytoprotection against the deleterious action of doxorubicin administration to pre-pubertal rats. However, further studies shall be undertaken to investigate the protective mechanisms involved in such germ cell preservation.