Coronavirus Disease-19 Quarantine Is More Detrimental Than Traditional Off-Season on Physical Conditioning of Professional Soccer Players.

Grazioli, R, Loturco, I, Baroni, BM, Oliveira, GS, Saciura, V, Vanoni, E, Dias, R, Veeck, F, Pinto, RS, and Cadore, EL. Coronavirus disease-19 quarantine is more detrimental than traditional off-season on physical conditioning of professional soccer players. J Strength Cond Res 34(12): 3316-3320, 2020-Beyond the severe health crisis, the coronavirus disease 2019 has also affected the high-performance sports scenario. In soccer, practitioners are concerned about the effects of long-term detraining on players' conditioning, and caution is required when activities return. This study assessed body composition, jump and sprint performance, hamstring eccentric strength, and intermittent cardiorespiratory fitness of 23 male professional soccer players who returned to training activities after 63 days of quarantine. The results were compared with their physical condition assessed before a pre-season phase as soon as they returned to training after a regular 24-day off-season period. In comparison with after off-season assessments, the quarantine induced significant increases in body mass, body fat mass, 10- and 20-m sprint times as well as decreases in countermovement jump height (p < 0.05). There were no significant changes in hamstring eccentric strength, squat jump height, and cardiorespiratory fitness (p > 0.05). In summary, we showed that 63 days of quarantine impaired several physical performance measures compared with regular off-season in soccer players. Given the present results, special attention should be given to body composition-related and speed power-related capabilities after long-term detraining in professional soccer.

Anti-Inflammatory effects of low-level laser therapy (660 nm) in the early phase in carrageenan-induced pleurisy in rat.

BACKGROUND AND OBJECTIVE: In the classic model of pleurisy there is little evidence about the anti-inflammatory effects of low-level laser therapy (LLLT) as well the dosage characteristics, such as wavelength, total energy, number and pattern of treatment. In this study we investigated the potential effects of LLLT on modulating the pro-inflammatory and anti-inflammatory mediators of acute inflammation in a rat pleurisy model. STUDY DESIGN/MATERIALS AND METHODS: A sample of 48 female Wistar rats were divided into control and experiential groups. An inflammation was induced by carrageenan (0.2 ml) injected into the pleural cavity. At 1, 2, and 3 hours after induction a continuous wave (20 mW) diode laser of the InGaAlP (660 nm) type was used in the four laser groups with different doses and treatment patterns. One group received a single dose of 2.1 J and the other three groups received a total energy of 0.9, 2.1, and 4.2 J. Four hours later the exudate volume, total and differential leukocytes, protein concentration, NO, IL-6, IL-10, TNF-alpha, and MCP-1 were measured from the aspirated liquid. RESULTS: All the treatment patterns and quantity of energy studied show significant reduction of the exudate volume (P<0.05). Using energy of 0.9 J only NO, IL-6, MCP-1 and IL-10 are significantly reduced (P<0.05). On the other hand, higher energies (2.1 and 4.2 J) significantly reduce all variables independently of the treatment pattern. The neutrophil migration has a straight correlation with the TNF-alpha (r = 0.551) and NO (r = 0.549) concentration. CONCLUSIONS: LLLT-660 nm induced an anti-inflammatory effect characterized by inhibition of either total or differential leukocyte influx, exudation, total protein, NO, IL-6, MCP-1, IL-10, and TNF-alpha, in a dose-dependent manner. Under these conditions, laser treatment with 2.1 J was more effective than 0.9 and 4.2 J.

Evaluation of renal enzymuria and cellular excretion as an marker of acute nephrotoxicity due to an overdose of paracetamol in Wistar rats.

INTRODUCTION: The present study was conducted to determine whether the urinary levels of excreted enzymes, gamma-glutamyltransferase (GGT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), aspartate (AST) and alanine aminotransferases (ALT), can efficiently indicate, within 24 h, an acute nephrotoxicity due to an overdose of paracetamol (PAR). METHODS: A baseline urine was collected from the experimental group. Thereafter, blood collected from the orbital sinus (1.0 ml) and paracetamol (650 mg/kg of body weight) was administered by gavage. After the drug administration, animals were returned to the metabolic cages and then urine was collected in the next 22 h. Blood and urine collection was performed at time 0+24 h (T(24)), as well as at times 48 and 72 h (T(48) and T(72)). After the last urine and blood collection, the rats were killed and the kidneys removed and prepared for histological examination. Plasma creatinine and urinary levels of creatinine (to determinate glomerular filtration rate-GFR), GGT, ALP, LDH, ALT and AST were measured. Kidney tissues were stained with hematoxylin and eosin stain for histological assessment. RESULTS: Urinary levels of GGT, ALP and LDH enzymes were significantly higher (P<0.05) at T(24) when compared to the levels at T(0) and returned to basal levels at T(48) and T(72). The number of urinary epithelial cells at T(24) was significantly higher when compared to the control time (T(0)) (P<0.001). The GFR was significantly reduced 24, 48 and 72 h after the drug administration. CONCLUSION: The number of urinary epithelial cells and urinary enzymes levels are a simple and low cost procedure that is available and can help in the detection of renal acute lesions.

Treatment with N-methyl-D-aspartate receptor antagonist (MK-801) protects against oxidative stress in lipopolysaccharide-induced acute lung injury in the rat.

Acute lung injury (ALI) and the acute respiratory distress syndrome (ARDS) are common syndromes that affect both clinical and surgical patients. This study describes the effects of a potent and specific N-methyl-d-aspartate receptor antagonist (MK-801) against oxidative stress in acute lung injury induced by intratracheal lipopolysaccharide (LPS) injection. This study was performed using male Wistar rats weighing 200-250g. Rats were randomly divided into four groups: control with isotonic saline instillation (n=6); LPS (100µg/100g of body weight) treated with saline (n=6); LPS treated with MK-801 (0.3mg/kg, intraperitoneally; n=6); LPS treated with MK-801 (0.3mg/kg, intratracheally; n=6). Twelve hours after the LPS instillation, rats were anesthetized and a bronchoalveolar lavage (BAL) was performed in order to determine the alveolar-capillary membrane alterations and the inflammatory infiltrate level. Blood and lung samples were isolated and assayed for oxidative stress variables and histopathologic analysis. The use of MK-801 decreased bronchoalveolar lavage fluid protein, LDH activity and inflammatory cells. Indeed, the treatment with MK-801 significantly attenuated lung oxidative damage and histopathologic alterations after LPS instillation. Our data provide the first experimental demonstration that MK-801 decreases oxidative stress and limits inflammatory response and alveolar disarray in lipopolysaccharide-induced acute lung injury.

N-methyl-D-aspartate glutamate receptor blockade attenuates lung injury associated with experimental sepsis.

BACKGROUND: The aim of this study was to examine the effects of the N-methyl-D-aspartate receptor (NMDAR) channel blocker dizocilpine (MK-801) on lung injury in rats submitted to experimental sepsis induced by cecal ligation and perforation (CLP). METHODS: Adult male Wistar rats submitted to CLP were given a single systemic injection of MK-801 (subcutaneously at 0.3 mg/kg) administered 4 or 7 h after CLP induction. Twelve hours after CLP BAL was performed to determine total cell count, protein content, and inflammatory parameters. In addition, lung was excised for histopathologic analyses and determination of NMDAR subunits content. In a separate cohort of animals mortality was recorded for 5 days. RESULTS: Animals submitted to sepsis induced by CLP showed an increase in the content of NMDAR subunits NR1 and NR2A in the lung. Administration of MK-801 4 h after CLP induction resulted in a decrease in BAL fluid cellular content and decreased levels of proinflammatory cytokines. In addition, MK-801 decreased lung oxidative stress markers and histopathologic alterations and improved survival. CONCLUSIONS: These findings indicate that NMDAR blockade might represent a promising novel therapeutic strategy for the treatment of sepsis and inflammatory disorders.

Nephroprotective and anti-inflammatory effects of aqueous extract of Melissa officinalis L. on acetaminophen-induced and pleurisy-induced lesions in rats

This study assessed the bioactive properties of an aqueous extract of M. officinalis for its anti-inflammatory activity and its protection against hepatic and renal lesions induced by acetaminophen (APAP). Animals pre-treated with the crude extract in pleurisy induced by carrageenan showed a reduction in the amounts of exudate, in the numbers of leukocytes and polymorphonuclear cells. Intragastric administration of the extract for seven days prior to the APAP-induced lesion showed no protective effect on the liver. The treatment with the extract induced an increase of serum aspartate aminotransferase, indicating a rise of toxicity. Contrarily, the same treatment reduced the APAP induced lesion in kidney, with respect to ν-glutamyltransferase. The results suggested that the extract was not hepatoprotective and could lead to an increase in the lesions induced by the APAP. On the other hand, the extract was nephroprotective against the lesions induced by the APAP and showed an anti-inflammatory effect on pleurisy carrageenan-induced.