Testicular histomorphometric patterns and spermatogenesis dynamics of Oecomys bicolor tomes, 1860 (Rodentia: Cricetidae).

Although the order Rodentia does not present a high risk of extinction compared to mammals as a whole, several families demonstrate high levels of threat and/or data deficiency, therefore highlighting the need for targeted research and the application of ecological and reproductive data to the development of conservation actions. The order Rodentia, the largest among mammals, includes 9 families, and the family Cricetidae is the most diverse of the Brazilian rodents. In Brazil, 12 of the 16 genera of Oecomys are found. Oecomys bicolor is known in Brazil as the 'arboreal rat' and is, found in dry, deciduous and tropical forests. The mean body weight of Oecomys bicolor was 35.8 g and the gonadal, tubular and epithelial somatic indexes were, 0.53%, 0.47% and 0.37%, respectively. Seminiferous tubules volume density was 89.72% and the mitotic and meiotic indexes corresponded to 8.59 and 2.45 cells, respectively, and the yield of spermatogenesis was 23.83 cells. The intertubular compartment represented 10.28% of the testis parenchyma and around 5% of the interstitial space was occupied by Leydig cells, whose number per gram of testis was 11.10 × 107 cells. By evaluating the biometric and histomorphometric characteristics of the testis, there is evidence that this species has a high investment in reproduction. Due to the high contribution of the seminiferous epithelium and the intertubular compartment in this species, compared to the others of the same family, it is possible to infer that the species Oecomys bicolor has a promiscuous reproductive behaviour.

Exploring the association between a standardized extract of pequi peels (Caryocar brasiliense Cambess) and blue light as a photodynamic therapy for treating superficial wounds.

Natural products derived from plants can be used as photosensitizers for antimicrobial photodynamic therapy (aPDT) combining key therapeutic strategies for tissue repair while controlling microorganisms' growth. We investigated a standardized extract of pequi peels (Caryocar brasiliense Cambess) as a brownish natural photosensitizer for aPDT using blue light. Three concentrations of the pequi extract (PE; 10, 30, or 90 µg/mL) were tested solely or associated with blue laser (445 nm, 100 mW, 138 J/cm2 , 6 J, 60 s). In vitro, we quantified reactive oxygen species (ROS), assessed skin keratinocytes (HaCat) viability and migration, and aPDT antimicrobial activity on Streptococcus or Staphylococcus strains. In vivo, we assessed wound closure for the most active concentration disclosed by the in vitro assay (30 µg/mL). Upon aPDT treatments, ROS were significantly increased in cell monolayers regardless of PE concentration. PE at low doses stimulates epithelial cells. Although PE stimulated cellular migration, aPDT was moderately cytotoxic to skin keratinocytes, particularly at the highest concentration. The antimicrobial activity was observed for PE at the lowest concentration (10 µg/mL) and mostly at PE 10 µg/mL and 30 µg/mL when used as aPDT photosensitizers. aPDT with PE 30 µg/mL presents antimicrobial activity without compromising the initial phases of skin repair.

Central giant cell granulomas of the jaws stromal cells harbour mutations and have osteogenic differentiation capacity, in vivo and in vitro.

BACKGROUND: Central giant cell granulomas (CGCG) of the jaws are osteolytic lesions that may behave aggressively and respond poorly to surgery. Microscopically, in addition to giant cells, there is a mononuclear cell population composed of macrophage/monocytic cells and spindle-shaped cells of mesenchymal origin. Seventy two percent of these tumours harbour mutually exclusive TRPV4, KRAS and FGFR1 mutations. We aimed to assess the mutational status of mononuclear and giant cells and the osteogenic potential of stromal cells in vitro and in vivo. METHODS AND RESULTS: We screened CGCG for signature mutations and used laser-capture microdissection to demonstrate that the mutations are restricted to the mononuclear cells. Additionally, we established CGCG primary cell culture and observed that the cells retained the mutations throughout passages. By flow cytometry, we observed predominance of CD14- CD51- CD61- cells, consistent with the expected profile for stromal cells. Considering the mesenchymal origin of stromal cells, we assessed the osteogenic differentiation potential of CGCG cells in culture by cytochemistry (von Kossa and alizarin red staining), alkaline phosphatase (ALP) activity assay and gene expression of osteogenic markers. CGCG cells presented self-capacity to increase ALP levels in a time-dependent manner and under osteogenic induction presented increasing number of calcium deposits, and overall higher expression of osteocalcin, RUNX2, ALPL and osteopontin than cells without osteogenic induction. A patient-derived xenograft model for CGCG was established, and osteoid material deposition was observed. CONCLUSION: Collectively, the results confirm that the signature mutations are restricted to stromal cells in CGCG, and the in vitro and in vivo results support that these cells have the capacity to differentiate into osteoblasts, in line with the bone formation often observed in the stroma of these lesions.

Thirty days of combined consumption of a high-fat diet and fructose-rich beverages promotes insulin resistance and modulates inflammatory response and histomorphometry parameters of liver, pancreas, and adipose tissue in Wistar rats.

OBJECTIVE: The aim of this study was to verify the effects of consumption of a high-fat diet (HFD) combined with fructose-rich beverages (FRT) in promoting metabolic and physiologic changes associated with insulin resistance. METHODS: Thirty-two male Wistar rats (250 ± 10 g) were randomly allocated into four groups (n = 8) that received either a standard diet (CON), HFD, FRT, or HFD + FRT for 30 d. Insulin sensitivity and glucose tolerance were evaluated using the insulin tolerance test (ITT) and oral glucose tolerance test (OGTT). Serum samples were used to analyze the metabolic parameters and hormone levels. Interleukin (IL)-6, IL-10, IL-1ß, and tumor necrosis factor-α assays were performed in the liver, pancreas, gastrocnemius muscle, and epididymal adipose tissue by enzyme-linked immunosorbent assay. Histologic and morphometric analyses were performed on the liver, pancreas, and adipose tissues. RESULTS: Consumption of HFD + FRT promoted a significant increase (P < 0.05) in body weight, index adiposity, and in the area under the curve of ITT (P < 0.001) and OGTT (P < 0.001) when compared with the CON group. Consumption of FRT alone increased fasting glucose (P = 0.015), insulin (P = 0.035), and homeostasis model assessment index (P = 0.018), and these changes were of greater magnitude when FRT was combined with HFD. Moreover, the rats fed an HFD + FRT demonstrated a significant increase in lipid droplets in the liver (P < 0.001), an increase in adipocyte area, and an increase in inflammatory cytokines in the liver, pancreas, skeletal muscle, and adipose tissue. CONCLUSION: Consumption of an HFD + FRT promotes insulin resistance, increases inflammatory cytokines, and modulates histomorphometric parameters of the liver, pancreas, and adipose tissue, typical of insulin resistance in humans.

Cellulose acetate nanofibers loaded with crude annatto extract: Preparation, characterization, and in vivo evaluation for potential wound healing applications.

In this study we prepared annatto-loaded cellulose acetate nanofiber scaffolds and evaluated both in vitro cytotoxicity and potential for wound healing in a rat model. Annatto extract, which has been used to accelerate wound healing, was added to cellulose acetate polymer and the resulting material was used to produce nanofiber scaffolds via electrospinning. Physicochemical, and thermal evaluation of the resulting nanofiber mats showed that incorporating annatto did not significantly affect the thermal or chemical stability of the polymer. Annatto extract did not demonstrate cytotoxicity in the HET-CAM assay or MTT assay for fibroblast culture. Scanning electron microscopy of the fibroblasts confirmed that cells spread and penetrated into the nanofiber. In vivo experiments confirmed that cellulose acetate retained its biocompatibility when associated with crude annatto extract, and suggested that dose/response modulation occurs between the annatto-functionalized nanofibers and mast cells, indicating the potential of this material for wound healing applications.

Comparative testis structure and function in three representative mice strains.

Mice are widely used as experimental models due to several positive characteristics and in particular their suitability for studies involving molecular biology and transgenesis. Despite the large number of mice strains currently available, the literature regarding their basic reproductive biology is still relatively scarce. Herein, we comparatively evaluated several important and correlated parameters related to testis structure and function in sexually mature male mice of inbred (C57BL/6, n = 19; BALB/c, n = 17) and outbred (Swiss, n = 17) strains, frequently utilized in research. Swiss mice presented significant variation for many parameters evaluated, including higher sperm production, mainly when compared to the C57BL/6 strain. However, some key parameters such as the duration of spermatogenesis, the Sertoli cell number per testis, and the spermatogenic efficiency were similar among the different strains. Although presenting significantly higher Leydig cell (LC) proportion and numbers per testis gram and per testis, the anogenital index was smaller in Swiss mice. Estradiol levels were lower in C57BL/6, whereas testosterone levels and 3ß-HSD expression were similar among strains. Regarding the LC/macrophages relationship, in comparison to the literature, we reported a much higher contribution of macrophages to the mouse intertubule. Thus, we estimated that there are around 1.6 macrophages per LC in BALB/c mice and this intriguing finding could be relevant to testis function in overall and spermatogonial biology in particular. Taken together, our results highlight the importance of knowing more accurately the testis structure and function in the different mice strains available for research, particularly when a specific testis parameter is being investigated.

Epithelial growth factor and decompressive testicular fasciotomy to control ischemia reperfusion injury in rats.

PURPOSE: Testicular torsion is an urological emergency and an important cause of male infertility. Recent studies have shown that not only ischemia, but also the restoration of blood flow creates a deleterious situation for the testis. The goal of this work was to evaluate the role of systemic epithelial growth factor application and its association with decompressive fasciotomy in tissue recovery of the testes undergoing the torsion of the spermatic cord. METHOD: Torsion of the spermatic cord was induced in 40 Wistar pubescent testes for a period of 4 h. At the time of detorsion systemic epithelial growth factor and decompressive fasciotomy were applied as treatment alternatives. After 21 days, the testicles were examined macro and microscopically. RESULTS: The variables evaluated were weight, testicular volume and the degree of histological alterations by optical microscopy. The rate of healing of testicular torsion showed significant difference between the groups. It was noted that in terms of testicular weight and volume the animals treated with systemic epithelial growth factor resembled the control group and had a better histological classification than the other groups. The mean Johnsen score was significantly higher in the group treated with systemic growth factor and decompressive testicular fasciotomy than in the group without fasciotomy. No significant changes were noted in the contralateral testes. CONCLUSION: Although decompressive testicular fasciotomy improved spermatogenesis, recovery was limited. Systemic epithelial growth factor administered in combination with decompressive testicular fasciotomy was more effective for spermatogenesis than fasciotomy alone. Administering epithelial growth factor after reperfusion might have the potential to decrease long-term histologic damage after testicular torsion. The combination of decompressive testicular fasciotomy and epithelial growth factor had a synergistic effect on the healing of these testes.

First insights for targeted therapies in odontogenic myxoma.

OBJECTIVE: Odontogenic myxoma (OM) occasionally responds poorly to surgical treatment. The MAPK pathway is constitutively activated in several neoplasms and we aimed to test if the MAPK pathway is activated in OM, in order to pave the way for an alternative therapy for aggressive and recurrent cases. MATERIALS AND METHODS: The immunoexpression of phosphorylated ERK1/2 (pERK1/2) was assessed in OM. We established a 3D organotypic culture model for the in vitro study and patient-derived xenografts (PDX) in mice for the in vivo study. The MEK inhibitor U0126 was used to inhibit phosphorylation of ERK1/2 in the in vitro and in vivo models. RESULTS: All OM showed strong pERK1/2 immunoexpression, consistent with MAPK pathway activation. Treatment of the 3D culture with U0126 resulted in a reduced pERK1/2/ERK1/2 ratio. Consistent with the in vitro results, all PDX of animals treated with U0126 showed a decreased volume fold change compared with controls. CONCLUSIONS: The MAPK pathway is activated in OM and its inhibition leads to tumor shrinkage in PDX and cell culture models. CLINICAL RELEVANCE: Our results offer a pre-clinical frame for OM-targeted therapy. Further work is needed to determine if this initial finding holds clinical promise.

Physical training improves exercise tolerance, cardiac function and promotes changes in neurotrophins levels in chagasic mice.

AIMS: To investigate the effects of moderate aerobic physical training on cardiac function and morphology as well as on the levels of glial cell-derived neurotrophic factor (GDNF), nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF) of animals infected with the Y strain of Trypanosoma cruzi. MAIN METHODS: Twenty-eight male C57BL/6 mice were distributed into 4 groups: sedentary control (SC), trained control (TC), sedentary infected (CHC) and trained infected (CHT). The infection was performed by intraperitoneal injection of trypomastigote forms and the animals were adapted to treadmill in the week before the beginning of the training protocol, initiated 45 days post infection. Maximal exercise test (TEM) was performed at the baseline as well as at the end of the 4th, 8th and 12th weeks of training. At the end of the 12th week, all animals were evaluated for cardiac morphology and function by echocardiography. KEY FINDINGS: CHC group showed a larger area of right ventricle (RVA), increased end-systolic volume and reduction in ejection fraction (EF), stroke volume (SV), cardiac output (CO) and fractional area change (FAC). The training reduced the RVA and improved the FAC of chagasic animals. GDNF level was higher in TC and CHC groups compared to SC in heart and BDNF levels were higher in CHC compared to SC in heart and serum. SIGNIFICANCE: Physical training ameliorated the cardiac function of infected animals and promoted adjusts in BDNF and GDNF levels. These findings evidenced these neurotrophins as possible biomarkers of cardiac function responsive to exercise stimulus.

Morphometric evaluation of the spermatogonial stem cell distribution and niche in vertebrates.

Morphometry is a classical quantitative method often used in biology to provide a data basis for functional interpretations/interactions of a particular organ or system. Herein we took advantage of this valuable approach to evaluate the spermatogonial stem cell niche using the horse testis and immunocytochemical localization of GFRA1 [glial cell line-derived neurotrophic factor receptor produced by Sertoli cells)] as an example. Using the NIH ImageJ free software, we describe in detail all the necessary steps to investigate this specific and crucial microenvironment. Based on several recently published papers from our research group, this approach has proved to be fast, simple, and adaptable to a wide range of species and has the potential to be easily reproducible in different laboratories.