Morphometric analysis of the effects of immobilization on the gastrocnemius muscle of rats

O objetivo deste trabalho e compreender os efeitos da imobilizacao em encurtamento do musculo gastrocnemio de ratos, por meio de analise de variaveis como peso e comprimento muscular, diametro das fibras e alteracoes morfologicas. Utilizamos 15 Rattus norvegicus machos da linhagem Wistar, distribuidos em tres grupos: Controle (GC), intactos em gaiolas por 7 dias; Imobilizado (GI) com a pata esquerda encurtada por 3 semanas e Imobilizado e Solto (GIS), imobilizados durante 3 semanas e, apos esse periodo, livres nas gaiolas durante 3 semanas, sem intervencao. Apos a eutanasia, os musculos foram coletados para as analises. A imobilizacao promoveu reducao de peso em todos os grupos. Nao houve alteracao significativa em relacao ao comprimento, exceto entre o GC e GIS (p=0,01). Na analise do diametro nao foi observada diferenca estatistica entre os grupos (p>0,05). As alteracoes morfometricas, apos imobilizacao, causaram reducao de peso e de comprimento. Na variavel diametro muscular, nao foram observadas diferencas estatisticamente significativas.The aim of this study is to analyze the effects of immobilization in shortening of the gastrocnemius muscle of rats, analyzing variables such as weight and muscle length, fiber diameter and morphological changes. We used 15 male Wistar rats, divided into three groups: control (CG), intact in cages for 7 days; Immobilized (IG) with the left leg shortened by three weeks and Immobilized and loose (IGL), immobilized for 3 weeks and after this period, free in Their cages for 3 weeks without intervention. The immobilization promoted weight loss in all groups. There was the Significant change in relation to length, except between CG and GIS (P = 0.01). In the statistical analysis of the diameter difference between groups (p> 0,05). Morphological changes after immobilization causes reduced weight and length. Muscle diameter variable in statistically significant differences were observed

Melatonin prevents age-related hearing loss in the murin experimental model

Objective: The present study aimed to perform a morphological and morphometric analysis of cochlear structures of C57BL/6J mice receiving oral melatonin for a 12-month period. Methods: 32 male C57BL/6J were divided into control and melatonin groups. Control received saline and ethanol solution and melatonin group, 50 L of 10 mg of melatonin/kg/day orally for a 12-month period. After de experiment the animals were sacrificed into a 40% concentration of CO2 chamber, and the blades were morphological and morphometrically analyzed. Results: The melatonin group revealed a higher median density of viable cells (45 ± 10.28 cells/100 m2, 31---73, vs. 32 ± 7.47 cells/100 m2, 25---48). The median area of stria vascularis was 55.0 ± 12.27 cells/100 m2 (38---80) in the control, and 59.0 ± 16.13 cells/100 m2 (40---134) in the melatonin group. The morphometric analysis of the spiral ligament reveals a higher median of total viable neurons in the melatonin (41 ± 7.47 cells/100 m2, 27---60) than in the control group (31 ± 5.68 cells/100 m2, 21---44). Conclusion: Although melatonin is a potent antioxidant, it does not completely neutralize the occurrence of presbycusis; however, it may delay the onset of this condition

Phylloseptin-1 is leishmanicidal for amastigotes of Leishmania amazonensis inside infected macrophages

Leishmania protozoans are the causal agents of neglected diseases that represent an important public health issue worldwide. The growing occurrence of drug-resistant strains of Leishmania and severe side effects of available treatments represent an important challenge for the leishmaniases treatment. We have previously reported the leishmanicidal activity of phylloseptin-1 (PSN-1), a peptide found in the skin secretion of Phyllomedusa azurea (=Pithecopus azureus), against Leishmania amazonensis promastigotes. However, its impact on the amastigote form of L. amazonensis and its impact on infected macrophages are unknown. In this work, we evaluated the effects of PSN-1 on amastigotes of L. amazonensis inside macrophages infected in vitro. We assessed the production of hydrogen peroxide and nitric oxide, as well as the levels of inflammatory and immunomodulatory markers (TGF-β, TNF-α and IL-12), in infected and non-infected macrophages treated with PSN-1. Treatment with PSN-1 decreased the number of infected cells and the number of ingested amastigotes per cell when compared with the untreated cells. At 32 µM (64 µg/mL), PSN-1 reduced hydrogen peroxide levels in both infected and uninfected macrophages, whereas it had little effect on NO production or TGF-β release. The effect of PSN-1 on IL-12 and TNF-α secretion depended on its concentration, but, in general, their levels tended to increase as PSN-1 concentration increased. Further in vitro and in vivo studies are needed to clarify the mechanisms of action of PSN-1 and its interaction with the immune system aiming to develop pharmacological applications

Melatonin prevents age-related hearing loss in the murin experimental model

Objective: The present study aimed to perform a morphological and morphometric analysis of cochlear structures of C57BL/6J mice receiving oral melatonin for a 12-month period. Methods: 32 male C57BL/6J were divided into control and melatonin groups. Control received saline and ethanol solution and melatonin group, 50 μL of 10 mg of melatonin/kg/day orally for a 12-month period. After de experiment the animals were sacrificed into a 40% concentration of CO2 chamber, and the blades were morphological and morphometrically analyzed. Results: The melatonin group revealed a higher median density of viable cells (45 ± 10.28 cells/100 μm2, 31–73, vs. 32 ± 7.47 cells/100 μm2, 25–48). The median area of stria vascularis was 55.0 ± 12.27 cells/100 μm2 (38–80) in the control, and 59.0 ± 16.13 cells/100 μm2 (40–134) in the melatonin group. The morphometric analysis of the spiral ligament reveals a higher median of total viable neurons in the melatonin (41 ± 7.47 cells/100 μm2, 27–60) than in the control group (31 ± 5.68 cells/100 μm2, 21–44). Conclusion: Although melatonin is a potent antioxidant, it does not completely neutralize the occurrence of presbycusis; however, it may delay the onset of this condition. Level of evidence: 3

Role of melatonin in prevention of age-related hearing loss.

INTRODUCTION:Age-related hearing loss (ARHL) is a consequence of aging of the auditory system. The best known mechanism of cell death in ARHL is apoptosis due to increased production of reactive oxygen species. In this context, it is hypothesized that melatonin, owing to its high antioxidant potential and its action in the mitochondria, helps prevent or delay outer hair cell dysfunction (HCD). AIMS:To evaluate the effect of melatonin on the prevention of HCD dysfunction in the ARHL process in a susceptible murine C57BL/6J model. METHOD:C57BL/6J animals were divided into two groups: control (CG) and melatonin (MG). The CG received a saline and ethanol solution and the MG, melatonin (10 mg/kg/day). The solutions were offered daily (50 μl) orally over a 10-month period. Distortion Product Otoacoustic Emissions (DPOAE) measurements were conducted once a month. RESULTS:There was a decrease in DPOAE values in both groups over time and a differentiation between them from the 10th month of life onwards. At 10 months, the MG maintained higher DPOAE values than the CG at all frequencies tested. CONCLUSION:The use of melatonin has otoprotective effects on HCD in the ARHL process in the C57BL/6J model

Perspectives on the Therapeutic Effects of Pelvic Floor Electrical Stimulation: A Systematic Review

Pelvic, perineal, and nervous lesions, which derive principally from pregnancy and childbirth, may lead to pelvic floor dysfunctions, such as organ prolapses and lesions in the nerves and muscles due to muscle expansion and physiology. It is estimated that 70% of women affected by this clinical picture have symptoms that do not respond to the classical treatments with antimuscarinic and anticholinergic drugs. Therefore, resorting to efficient alternatives and less invasive methods is necessary to assist this public health problem that predominantly affects the female population, which is more susceptible to the risk factors. This study aimed to perform an updated and comprehensive literature review focused on the effects of pelvic floor electrical stimulation, considering new perspectives such as a correlation between electric current and site of intervention and other molecular aspects, different from the present reviews that predominantly evaluate urodynamic aspects. For that purpose, PubMed and ScienceDirect databases were used to perform the search, and the Methodi ordinatio method was applied. With well-researched therapeutic effects, electrical stimulation induced promising results in histological, nervous, and molecular evaluations and spinal processes, which showed beneficial results and revealed new perspectives on ways to evoke responses in the lower urinary tract in a non-invasive way. Thus, it is possible to conclude that this type of intervention may be a non-invasive alternative to treat pelvic and perineal dysfunctions

Effects of Fish Oil Supplementation on Oxidative Stress Biomarkers and Liver Damage in Hypercholesterolemic Rats

Metabolic syndrome, especially its component related to dyslipidemia, is related to the development of nonalcoholic fatty liver disease (NAFLD), which is a disease with a significant global prevalence. Supplementation with omega-3 polyunsaturated fatty acids emerged as a complementary therapeutic possibility for dyslipidemia, but its benefits are questioned. This paper aims at evaluating the effects of fish oil supplementation in rats with hypercholesterolemia induced by hypercholesterolemic diet (HD). The study design is based on an experimental model in which the animals were randomly divided into 3 groups: G1 (standard commercial feed + saline solution); G2 (hypercholesterolemic diet + saline solution) and G3 (hypercholesterolemic diet + fish oil) over a period of 16 weeks. Metabolic control parameters and oxidative stress biomarkers were evaluated according to standardized methodologies. The G3 group showed significantly lower values of plasma concentrations of TG, and hepatic myeloperoxidase as well as higher erythrocyte superoxide dismutase activity (p < 0.05). Regarding histopathological analysis, there was lipid accumulation in the liver of animals from group G2; meanwhile, hepatocytes reorganization and expressive reduction of lipid vacuoles and hepatic TG content was observed in group G3. This study demonstrated how fish oil supplementation reduced the plasma concentration and hepatic content of triglycerides, as well as liver tissue damage in histopathological analysis