Semen Parameter Alteration, Histological Changes and Role of Oxidative Stress in Adult Rat Epididymis on Exposure to Electronic Cigarette Refill Liquid.

Electronic cigarettes (e-cigarettes) are devices intended to substitute conventional cigarettes, with the aim of being less harmful. In a previous report, we showed that intraperitoneal (i.p.) injection of e-cigarette liquid (E-liquid), with or without nicotine, induced toxicity in the testes of Wistar rats by disrupting oxidative balance and steroidogenesis. In the present work, we further evaluated the impact of e-liquid with or without nicotine on the epididymis of rats using the same procedure. Results showed that e-liquid treatments led to alteration of semen parameters, with a significant drop of at least 50% in sperm vitality, a significant increase of morphologically abnormal spermatozoa and an imbalance of redox status in comparison to the control group. A significant raise of 1.4 fold, compared to the untreated rats, in myeloperoxidase (MPO) granules after both treatments was recorded, suggesting an inflammatory state. Histopathological examination confirmed a marked reduction in sperm count in the cauda epididymis. Data of this study suggest that the pro-oxidant properties of e-liquid with or without nicotine, in addition to testicular defects, could lead to an inflammatory state in the epididymis, causing alterations in the semen parameters. These data provide additional information on the impact of e-liquid on the reproductive system.

Prophylactic and curative effect of rosemary leaves extract in a bleomycin model of pulmonary fibrosis.

CONTEXT: Pulmonary fibrosis is a devastating disease without effective treatment. Rosemary is appreciated since ancient times for its medicinal properties, while biomolecules originated from the plant have an antioxidant and antifibrotic effect. OBJECTIVE: The effects of Rosmarinus officinalis L. (Lamiaceae) leaves extract (RO) on bleomycin-induced lung fibrosis were investigated. MATERIALS AND METHODS: Male Wistar rats were given a single dose of bleomycin (BLM, 4 mg/kg, intratracheal), while RO (75 mg/kg, intraperitoneal) was administered 3 days later and continued for 4 weeks (BLM/RO1-curative group). Alternatively, RO was administered 2 weeks before BLM and continued 15 days thereafter (BLM/RO2-prophylactic group). Antioxidant activities of RO and lung tissues were studied by standard methods. Histological staining revealed lung architecture and collagen deposition. RO was characterized for its polyphenol content and by high-performance liquid chromatography. RESULTS: RO polyphenol content was 60.52 mg/g of dry weight, carnosic and rosmarinic acids being major components (6.886 and 2.351 mg/g). Antioxidant effect of RO (DPPH and FRAP assay) expressed as IC50 values were 2.23 µg/mL and 0.074 µg/mL, respectively. In BLM/RO1 and BLM/RO2 lung architecture was less compromised compared to BLM, which was reflected in lower fibrosis score (2.33 ± 0.33 and 1.8 ± 0.32 vs 3.7 ± 0.3). Malondialdehyde levels were attenuated (141% and 108% vs 258% of normal value). Catalase and glutathione-S-transferase activities were normalized (103% and 117% vs 59%, 85% and 69% vs 23%, respectively). DISCUSSION AND CONCLUSION: RO has a protective effect against BLM-induced oxidative stress and lung fibrosis due to its phenolic compounds.

Impact of e-cigarette refill liquid exposure on rat kidney.

Electronic-cigarettes (e-cigarette), the alternative to classic cigarettes are becoming extremely popular but their safety is not still established. Recent studies have showed cytotoxic effects of the electronic cigarette and its recharge e-liquid, in vitro. The present study was designed to evaluate e-cigarette liquid nephrotoxicity in rats. For this purpose, 32 rats were treated for 28 days as follows: Control group was injected intraperitoneally with NaCl 9 g/l; e-cigarette 0% treated group received an intraperitoneal injection of e-liquid without nicotine diluted in NaCl 9 g/l, e-cigarette treated group, received an intraperitoneal injection of e-liquid containing 0.5 mg of nicotine/kg of body weight/day diluted in NaCl 9 g/l and nicotine-treated group received an intraperitoneal injection of 0.5 mg of nicotine/kg of body weight/day diluted in NaCl 9 g/l. In nicotine group, creatinine level was increased, whereas urea and acid uric levels were decreased. In e-liquid-exposed groups, levels of uric acid and mainly urea were lower. Interestingly, after e-liquid exposure, oxidative stress status showed increased total protein and sulfhydril content, whereas superoxide dismutase and catalase activities were decreased. However, the levels of lipid peroxides were not increased after e-liquid exposure. Histological studies identified excess of cells with reduced and dark nuclei exclusively located in the renal collecting ducts. Thus, e-liquid seems to alter anti-oxidant defense and to promote minor changes in renal function parameters. This preliminary study raises some flags about possible nephrotoxicity of e-cigarette liquids in rats. As some features observed in rats may not be observed in human smokers, additional studies are needed to further qualify conclusions that might be applicable to actual users of e-cigarettes.

Neurobehavioral assessment following e-cigarette refill liquid exposure in adult rats.

The present study was conducted to assess the toxic effect of e-cigarette refill liquid on cognitive and motor functions in adult rats. Animals were administered 28 µl/kg of body weight of e-liquid with/without a dose of 0.5 mg of nicotine/kg of body weight, using the intraperitoneally route for a period of 4 weeks. They were then evaluated by novel object recognition test (NORT) and spontaneous alternation T-maze test for cognitive functions. Results indicated that e-liquid without nicotine induced, in the NORT, a decrease in time exploring the novel object during the test session and lower discrimination and recognition indexes compared to control and e-liquid with nicotine treated rats. Furthermore, short-term spatial memory was affected after e-liquid treatment in the spontaneous alternation T-maze test, identifying recognition memory impairments. However, none of the treatments altered motor functions assessed by inclined plane test, Kondziela's inverted screen test and weights test. Cell cytotoxicity assessment following e-liquid exposure showed a significant decrease in hippocampal cell viability, but no change in cortical cell viability. Thereby, e-liquid without nicotine causes cognitive impairments, especially on the hippocampus. Based on these results, more extensive assessments on e-cigarettes must be carried out.

Impact of e-cigarette refill liquid with or without nicotine on liver function in adult rats.

This study was conducted to evaluate the effects of e-cigarette refill liquid administration alone or with nicotine on the antioxidant defense status, functional and histopathological changes in adult rat liver tissue. For this purpose, 32 rats were treated for 28 days as follows: control group was injected intra-peritoneally with physiological saline; e-cigarette 0% treated group received an intra-peritoneal injection of e-liquid without nicotine diluted in physiological saline, e-cigarette-treated group received an intra-peritoneal injection of e-liquid containing 0.5 mg of nicotine/kg of body weight/day diluted in physiological saline and nicotine-treated group received an intra-peritoneal injection of 0.5 mg of nicotine/kg of body weight/day diluted in physiological saline. In e-liquid without nicotine-exposed group, activities of the liver biomarkers aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and lactate dehydrogenase increase. Interestingly, oxidative stress indicators showed decreased total protein content, associated with a reduction in the antioxidant enzymes activities superoxide dismutase, catalase and glutathione-S-transferase, and an elevation in malondialdehyde content, highlighting the promotion of lipid peroxidation and oxidative stress. Histological studies identified inflammatory cells infiltration and cell death. Thus, e-liquid seems to promote oxidative tissue injuries, which in turn lead to the observed histopathological finding. In comparison, nicotine alone induced less oxidative stress and less histopathological disorders, whereas e-liquid with nicotine gave rise to more histopathological injuries. Thereby, e-liquid, per se, is able to induce hepatotoxicity and supplementation with nicotine worsens this state.

Changes in glucose metabolism and reversion of genes expression in the liver of insulin-resistant rats exposed to malathion. The protective effects of N-acetylcysteine.

Organophosphorus pesticides are known to disturb glucose homeostasis and increase incidence of metabolic disorders and diabetes via insulin resistance. The current study investigates the influence of malathion on insulin signaling pathways and the protective effects of N-acetylcysteine (NAC). Malathion (200 mg/kg) and NAC (2 g/l) were administered orally to rats, during 28 consecutive days. Malathion increases plasma glucose, plasma insulin and glycated hemoglobin levels. Further, we observed an increase of insulin resistance biomarkers and a decrease of insulin sensitivity indices. The GP, GSK3ß and PEPCK mRNA expressions were amplified by malathion while, the expression of glucokinase gene is down-regulated. On the basis of biochemical and molecular findings, it is concluded that malathion impairs glucose homeostasis through insulin resistance and insulin signaling pathways disruptions in a way to result in a reduced function of insulin into hepatocytes. Otherwise, when malathion-treated rats were compared to NAC supplemented rats, fasting glucose and insulin levels, as well as insulin resistance indices were reduced. Furthermore, NAC restored liver GP and PEPCK expression. N-acetylcysteine showed therapeutic effects against malathion-induced insulin signaling pathways disruption in liver. These data support the concept that antioxidant therapies attenuate insulin resistance and ameliorate insulin sensitivity.

Effects of dimethoate in male mice reproductive parameters.

The aim of the current study was to investigate the ability of dimethoate (DMT) to induce reprotoxicity in male mice. The dose (20 mg/kg/day) was given orally for 30 days. A significant decrease in sperm count, motility and viability and a significant increase of morphologically abnormal spermatozoa percent in DMT treated mice was observed. Testicular Acetylcholinesterase (AChE) and Butyrylcholinesterase (BChE) activities were inhibited. Also, a significant increase in lipid peroxidation level and a significant decrease in the activities of antioxidant enzymes were observed in testis of DMT mice. In addition, gene expression of glutathione peroxidase 4 (GPx4) was quantified in RNA samples extracted from the testis by real-time reverse transcription-polymerase chain reaction (RT-PCR). Compared with control, mRNA expression of GPx4 was slightly decreased after DMT-exposure.

A comparative study on toxicity induced by carbosulfan and malathion in Wistar rat liver and spleen.

Organophosphorus (OP) and carbamate (CM) pesticides are widely used in agriculture. These pesticides are highly toxic to humans and their residues in food pose potential threat to human health. In this comparative study, we investigated the effect of subchronic exposure of OPs (malathion, MAL) and CM (Carbosulfan, CB) on rat liver and spleen. Biochemical analysis showed that levels of hepatic enzymes (ALT, ALP, LDH and PAL) changed after exposure to the pesticides. In the liver extracts, lipid peroxidation index increased after the treatment by pesticides. Our results indicated that exposure to MAL and CB leads to alteration of liver redox status. Both pesticides induced focal inflammation and fibrosis in the liver. After subchronic administration of MAL (200 mg/kg) and CB (25 mg/kg), systemic inflammation, as depicted by the increase in IFN-δ activity in liver, was observed in both malathion and carbosulfan treated animals. In addition, the results showed that MAL significantly increased TCD4+ and TCD8+ lymphocyte number. It also decreased INF-δ and IL-4 production. However, CB induced a reduction of TCD8+ number and cytokine production in spleen cells. In conclusion, malathion and carbosulfan had significant immunomodulatory properties in the spleen with inflammation and oxidative stress induction in the liver.

Carbosulfan-induced oxidative damage following subchronic exposure and the protective effects of N-acetylcysteine in rats.

Carbosulfan (CB)-induced oxidative stress leads to the inevitable accumulation of free radicals and eventual alteration of antioxidant enzymes in various biological systems. The present study is designed to investigate the preventive effect of N-acetylcysteine (NAC) on carbosulfan-induced hepatic and renal dysfunction in rats. Rats exposed to CB and NAC were examined for toxicity by assessing various biochemical alteration and stress markers including in liver and kidney. Significant increases of blood alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma glutamyltransferase (GGT), creatinine and urea were detected in CB-treated rats. In addition, the levels of antioxidative enzymes such as catalase (CAT), superoxide dismutase (SOD) and reduced glutathione (GSH) also were assessed. According to the results, rats exposed to carbosulfan showed a significant increase in the accumulation of stress markers and an alteration in the antioxidative enzymes activity, when compared to their respective controls. Interestingly, administration of NAC to CB-treated rats attenuates the toxicity of this compound, objectified by biochemical and oxidative improvement of liver and kidney. Thus, the present study reports for the first time that NAC could be a promising therapeutic agent against CB induced oxidative stress.

Lipid metabolism disturbances contribute to insulin resistance and decrease insulin sensitivity by malathion exposure in Wistar rat.

Several studies showed that organophosphorus pesticides disturb glucose homeostasis and can increase incidence of metabolic disorders and diabetes via insulin resistance. The current study investigates the influence of malathion on glucose metabolism regulation, in vivo, during subchronic exposure. Malathion was administered orally (200 mg/kg), once a day for 28 consecutive days. Plasma glucose, insulin and Glycated hemoglobin levels were significantly increased while hepatic glycogen content was decreased in intoxicated animals compared with the control group. Furthermore, there was a significant disturbance of lipid content in subchronic treated and post-treated rats deprived of malathion for one month. In addition, we used the homeostasis model assessment (HOMA) to assess insulin resistance (HOMA-IR) and pancreatic ß-cell function (HOMA-ß). Our results show that malathion increases insulin resistance biomarkers and decreases insulin sensitivity indices. Statistical analysis demonstrates that there was a positive and strong significant correlation between insulin level and insulin resistance indices, HOMA-IR, HOMA-ß. Similarly, a negative and significant correlation was also found between insulin level and insulin sensitivity indices. For the first time, we demonstrate that malathion induces insulin resistance in vivo using homeostasis model assessment and these changes were detectable one month after the end of exposure. To explain insulin resistance induced by malathion we focus on lipid metabolism disturbances and their interaction with many proteins involved in insulin signaling pathways.

Oxidative stress and alteration of biochemical markers in liver and kidney by malathion in rat pups.

The present study was undertaken to determine the effects of malathion exposure through maternal milk on oxidative stress, functional an metabolic parameters in kidney and liver of rat pups. We found that lactational exposure to malation (200 mg/kg, body weight (bw)) induced an oxidative stress status assessed by an increase in malondialdhyde (MDA) content, reflecting lipoperoxidation, a decrease in thiol groups' content as well as depletion of enzyme activities as a superoxide dismutase (SOD) and catalase (CAT) on postnatal days (Pnds) 21 and 51. Moreover, the current study showed that malathion induced liver and kidney dysfunctions demonstrated by considerable increase in phosphatase alkaline (PAL), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities as well as total and direct bilirubin, creatinine urea and acid uric contents. We also observed an increase in triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and a decrease in high-density lipoprotein cholesterol (HDL-C) in the plasma of treated rat pups. These findings evidenced that malathion exposure during lactation through maternal milk of rats pups induced kidney and liver oxidative stress as well as functional and metabolic disorders that play a role in the development of others pathologies as cardiovascular diseases and cancers.

Recovery by N-acetylcysteine from subchronic exposure to Imidacloprid-induced hypothalamic-pituitary-adrenal (HPA) axis tissues injury in male rats.

Imidacloprid is the most important example of the neonicotinoid insecticides known to target the nicotinic acetylcholine receptor in insects, and potentially in mammals. N-Acetyl-l-cysteine (NAC) has been shown to possess curative effects in experimental and clinical investigations. The present study was designed to evaluate the recovery effect of NAC against Imidacloprid-induced oxidative stress and cholinergic transmission alteration in hypothalamic-pituitary-adrenal (HPA) axis of male rats following subchronic exposure. About 40 mg/kg of Imidacloprid was administered daily by intragastric intubation and 28 days later, the rats were sacrificed and HPA axis tissues were removed for different analyses. Imidacloprid increased adrenal relative weight and cholesterol level indicating an adaptive stage of the general alarm reaction to stress. Moreover, Imidacloprid caused a significant increase in malondialdehyde level, the antioxidants catalase, superoxide dismutase and glutathione-S-transferase showed various alterations following administration and significant depleted thiols content was only recorded in hypothalamic tissue. Furthermore, the hypothalamic and pituitary acetylcholinesterase activity and calcium level were significantly increased highlighting the alteration of cholinergic activity. The present findings revealed that HPA axis is a sensitive target to Imidacloprid (IMI). Interestingly, the use of NAC for only 7 days post-exposure to IMI showed a partial therapeutic effect against Imidacloprid toxicity.

Effects of N-acetyl-l-cysteine, in vivo, against pathological changes induced by malathion.

Malathion toxicity has been related to the inhibition of acetylcholinesterase, induction of oxidative stress, liver damage and impairment of kidney function as well as hematotoxicity. N-acetyl-l-cysteine (NAC) has been shown to possess curative effects in experimental and clinical investigations. The present study was designed to evaluate the protective effect of NAC against toxic consequences of malathion exposure in Wistar rats. Malathion was given daily to rats via oral gavage and NAC in drinking water during seven days. When malathion-treated rats were compared with control, a leukocytosis and reduced hemoglobin (HGB) content were detected. Furthermore, malathion produced a significant increase in liver enzymes such as alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase and creatinine kinase. In addition, a decrease in acid phosphatase activity, protein and globulin levels were observed in malathion-treated rats compared with control. Moreover, analyses of the mineral status showed a disturbance in calcium, magnesium, phosphore and iron contents of the malathion-treated rats. Interestingly, NAC showed therapeutic effects against malathion toxicity. Indeed, HGB content and all liver enzymes were restored to normal values. Finally, the use of NAC as therapeutic agent for only seven days during malathion exposure showed interesting results on tissues damages.

Immunosuppression and oxidative stress induced by subchronic exposure to carbosulfan in rat spleen: immunomodulatory and antioxidant role of N-acetylcysteine.

The present study was designed to determine the immunosuppressive effects of carbosulfan (CB) and their relationship with an increased formation of reactive oxygen species in rat. Further, we aimed to evaluate the protective effects of N-acetyl-cysteine (NAC) against immunopathological changes induced by CB. Carbosulfan (25 mg/kg) and NAC (2 g/l) were given daily to rats during 30 days, via oral gavage and drinking water, respectively. Cell-mediated immune function, cytokines production, biomarkers of cell redox state maintenance, lipid peroxidation and the activities of antioxidant enzymes were measured in the spleen. Our data showed an increase in WBC percent (28.42%), a reduction in spleen CD8 T-lymphocytes (-85.63%) and a decrease in immunosuppressive cytokines production such as INF-gamma and IL-4. There was a switch from Th1-type to Th2-type cytokines with an unbalance toward anti-inflammatory cytokines. Moreover, a significant decrease in reduced glutathione (-71.68%) and total thiols (-39.81%) levels were observed in treated rats. Conversely, malondialdehyde level in spleen was increased (-42.3%), while glutathione-S-transferase, glutathione peroxidase, superoxide dismutase and catalase activities were depleted. Our results suggest that subchronic CB administration affects cellular enzyme and non-enzyme-mediated antioxidant defense systems and promotes immunotoxicity in rat. On the other hand, our data showed protective effects of NAC. Indeed, there was a recovery of oxidative stress markers and cytokines production. The use of NAC, in our study, as a therapeutic agent showed interesting results against CB toxicity.

Date seeds alleviate behavioural and neuronal complications of metabolic syndrome in rats.

Unhealthy dietary habits can play a crucial role in metabolic damages, promoting alteration of neural functions through the lifespan. Recently, dietary change has been perceived as the first line intervention in prevention and/or treatment of metabolic damages and related diseases. In this context, our study was designed to assess the eventual therapeutic effect of date seeds administration on memory and learning and on neuronal markers in a rat Metabolic Syndrome model. For this purpose, 32 adult male Wistar rats were fed with standard diet or high-fat high-sugar diet during ten weeks. After this, 16 rats were sacrified and the remaining rats received an oral administration of 300 mg of date seeds/kg of body weight during four supplementary weeks. Before sacrifice, we evaluate cognitive performances by the Barnes maze test. Afterwards, neuronal, astrocytic, microtubular and oxidative markers were investigated by immunoblotting methods. In Metabolic syndrome rats, results showed impairment of spatial memory and histological alterations. We identified neuronal damages in hippocampus, marked by a decrease of NeuN and an increase of GFAP and pTau396. Finally, we recorded an increase in protein oxidation and lipid peroxidation, respectively identified by an up-regulation of protein carbonyls and 4-HNe. Interestingly, date seeds administration improved these behavioural, histological, neuronal and oxidative damages highlighting the neuroprotective effect of this natural compound. Liquid Chromatography-Mass Spectrometry (LC-MS) identified, in date seeds, protocatechuic acid, caffeoylshikimic acid and vanillic acid, that could potentially prevent the progression of neurodegenerative diseases, acting through their antioxidant properties.

Spermatogenesis and steroidogenesis disruption in a model of metabolic syndrome rats.

CONTEXT: Metabolic syndrome (MetS) is a clustering of several physiological alterations. OBJECTIVE: This study was designed to evaluate the effects of MetS on rats spermatogenesis and steroidogenesis. MATERIALS AND METHODS: We developed a MetS rodent model using high-sugar and high-fat diet. RESULTS: MetS rats showed severe disorders in sperm parameters. Interestingly, a significant increase in malondialdehyde level and a decrease in the antioxidant activities were observed. Moreover, qRT-PCR analysis showed Bax down-regulation and Bcl-2 up-regulation. A decrease in testosterone level was identified, correlated with the CYP11A1, CYP17A1 and 17ß HSD testicular marker down-regulation. Finally, MetS rats showed an up-regulation of pro-inflammatory cytokines receptors IL-1R and IL-6R. CONCLUSION: MetS induced severe testis toxicity in male rats. Mets markedly distorted sperm parameters, inhibited the transcription of steroidogenic enzymes and led to oxidative stress, inflammation, and alteration of Bax/Bcl-2 ratioin testicular tissues.

Effect of age-dependent exposure to lead on hepatotoxicity and nephrotoxicity in male rats.

Lead is known to induce a broad range of physiological, biochemical, and behavioral dysfunctions in laboratory animals and humans. This includes age-specific variations in absorption, retention, and tissue distribution of lead. This study was carried out to investigate the effects of chronic exposure to lead (50 mg/L) on liver and kidneys of two different age groups of male rats treated with lead from delivery until puberty period (40 days) and postpuberty period (65 days). For this purpose, the concentrations of thiobarbituric acid reactive substance (TBARS), total thiol groups (SH), and superoxide dismutase (SOD) activity were measured in the liver and kidney of rats. Renal function was analyzed by determining creatinine, acid uric, and urea. Plasma activities of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and albumin were determined spectrophotometrically to evaluate hepatic function. These markers of damage were determined to assess the level of toxicity in these animals. Our results clearly show that the administration of lead produces oxidative damage in liver and kidney, as strongly suggested by the significant increase in TBARS, decrease in total SH, and the alteration of SOD activity. In young lead-exposed animals, lead-induced perturbations on the synthetic function of the liver and the kidney were more pronounced. However, nephropathy is evident for adult lead-exposed animals. It is concluded that lead induces severe hepatic and renal toxicity, which depends on the age of the animals and the target organ.

Influence of nitric oxide synthase inhibition on vasopressin and corticosterone secretion during water deprivation in rats.

Nitric oxide (NO) is a short-lived radical that functions as a neurotransmitter in the central nervous system and plays a physiological role in the regulation of hypothalamic-pituitary-adrenal axis and vasopressinergic axis. In the present study, we aimed to investigate the interaction between the generation of NO and vasopressin (AVP) and corticosterone release after 3 days of water deprivation in rats. Animals were previously treated with intraperitoneal (i.p.) saline or L-nitro-arginine methyl ester (L-NAME) injection. L-NAME is a nonspecific inhibitor of nitric oxide synthases. In control rats given i.p. saline or L-NAME, hypothalamic, pituitary, and plasma AVP levels and plasma corticosterone did not change from baseline levels (p>0.05). Three days of water deprivation increased significantly the corticosterone levels in plasma (p<0.01) and AVP levels in hypothalamus and plasma (p<0.01), but not in pituitary, which showed a significant decrease. These variations were concomitant with the elevation of nitrates/nitrates in plasma. L-NAME injection abolished significantly (p<0.01) the elevation of plasma corticosterone and hypothalamic AVP levels induced by water deprivation. These findings showed that in water-deprived rats, nitric oxide synthase inhibition by L-NAME inhibits corticosterone and vasopressin release, suggesting a potent stimulatory role of NO.

The effect of players' standard and tactical strategy on game demands in men's basketball.

The purpose of the present study was to examine the effects of competitive level and team tactic on game demands in men's basketball. Sixteen international-level male basketball players (INPs) and 22 national-level male basketball players (NLPs) were studied during 6 games. Time-motion analysis was performed to track game activities. Game physiological demands were assessed by monitoring heart rate (HR) and blood-lactate concentration. Results showed that INPs sprinted significantly more and performed more high-intensity shuffling than did NLPs (p < 0.05). Game-activity changes and frequency of high-intensity bouts were similar in man-to-man and zone-marking games (1,053 vs. 1,056 and 253 vs. 224, respectively, p > 0.05). Time spent in the maximal (>95% of HRmax) and high-intensity zone (85-95% of HRmax) was greater in the INPs than in the NLPs (17.8 vs. 15.2%, p < 0.01 and 59.1 vs. 54.4%, p < 0.05, respectively). No significant differences in mean HR were evident between man-to-man and zone-marking games (93.3 ± 2.1 vs. 92.8 ± 1.8% of HRmax, p > 0.05). Blood-lactate concentration was higher in the INPs than in the NLPs (6.60 ± 1.22 vs. 5.66 ± 1.19 mmol·L⁻¹ at halftime and 5.65 ± 1.21 vs. 4.43 ± 1.43 mmol·L⁻¹ at full time, p < 0.05). No mean or peak blood-lactate concentration differences resulted between man-to-man and zone-marking games (5.15 ± 1.32 vs. 5.83 ± 1.10 and 5.90 ± 1.25 vs. 6.30 ± 1.27 mmol·L⁻¹, respectively, p > 0.05). These results suggest an effect of competitive level over game demands in men's basketball. No marking strategy effect was evident. Basketball coaches and fitness trainers should develop the ability to repeatedly perform high-intensity activity during the game. Repeated sprinting and high-intensity shuffling ability should be trained to successfully play man-to-man and zone defense, respectively.

Activity profile and physiological requirements of junior elite basketball players in relation to aerobic-anaerobic fitness.

The aim of this research was to examine the demands of competitive basketball games and to study the relationship between athletes' physical capability and game performance. Physical and physiological game demands and the association of relevant field test with game performance were examined in 18 male junior basketball players. Computerized time-motion analysis, heart rate (HR), and blood-lactate concentration [BL] measurements were performed during 6 basketball games. Players were also measured for explosive power, speed, agility, and maximal-strength and endurance performance. During the games, players covered 7,558 +/- 575 m, of which 1,743 +/- 317; 1,619 +/- 280; and 2,477 +/- 339 m were performed at high, moderate, and low intensities, respectively. The 19.3 +/- 3.5 and 56.0 +/- 6.3% of the playing time was spent above 95% and at 85-95% of maximal HR, respectively. Average and mean peak [BL] were 5.75 +/- 1.25 and 6.22 +/- 1.34 mmolxL, respectively. Distances covered at maximal- and high-speed running significantly (p < 0.01) decreased during the second half. Game maximal- and high-speed running were significantly correlated with endurance performance (r = 0.52, p < 0.05 and r = 0.49, p < 0.05, respectively). High-intensity shuffling distance resulted in being negatively related with agility (r = -0.68, p < 0.05). This study showed that basketball players experience fatigue as game time progresses and suggests the potential benefit of aerobic and agility conditioning in junior basketball.