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.

Angiogenesis in patient-derived xenografts of odontogenic myxoma

Previously, by employing 3D organotypic tissue culture and patient-derived xenograft (PDX) model, oral myxoma response to a MAPK/MEK inhibitor was observed. Gross examination of the tumour fragments obtained after 55 days of PDX grafting revealed increased capsule vascularization. Microscopic analyses showed blood capillaries intermixed with myxoma cells, but the origin of these capillaries, from mice or humans, was not established. This study aimed to investigate whether the endothelial cells observed in the myxoma PDX model are derived from the mouse or from the primary human tumour. Immunohistochemistry was performed on five tumour fragments from the PDX of myxoma after 55 days of implantation in mice. Immunopositivity for antibodies against human (HLA-ABC) and mouse (H2 Db/H2-D1) major histocompatibility complex class I (MHCI) was assessed in the endothelial cells. The endothelial cells in the PDX fragments revealed a membrane staining for the human MHCI protein in the PDX tumour and adjacent connective tissue capsule, indicating that capillaries were derived from the human tumour fragment. Considering the probable human origin of the endothelial cells from capillary blood vessels in the myxoma PDX, we conclude that this PDX model is an interesting model to study myxoma angiogenesis.

Sperm production and seminal analyses in a Neotropical sperm-storing vespertilionid bat yellowish myotis (Myotis levis)

Yellowish myotis is a Neotropical vespertilionid bat that presents a seasonal reproduction. The sperm is produced in the Mature stage, stored in the Regressed stage and released in the Rest stage (mating period). Aiming to understand, for the first time, the relationship between testis and epididymis physiology in yellowish myotis reproduction, the spermatogenesis length, sperm production, and seminal parameters were herein evaluated. Fifty-one adult male bats were captured in Santuário do Caraça, Minas Gerais, Brazil. The gonads were collected in the Maturing and Mature stages for histomorphometric and immunohistochemical analyses, whereas the epididymis was evaluated in all reproductive stages for seminal studies. Our results demonstrated that the yellowish myotis spermatogenic process is fast, lasting 31.70 ± 0.15 days. Despite the low Sertoli cell efficiency (6.60 ± 1.23), the high numbers of Sertoli cells per testis enable an elevated sperm production in the Mature stage. The sperm concentration, vitality, and motility presented the highest values in the Regressed stage; however, in this period, an increased incidence of sperm morphological defects was detected. In the following period (Rest stage), a drastic reduction of defective sperm was observed, suggesting quality control of sperm before the mating period. Furthermore, the epididymis ability to maintain a long-term sperm-storage was observed in 26.7% of the bats in the Maturing stage. In summary, yellowish myotis presented a fast and high sperm production during the Mature stage. These sperms are stored and selected before mating period.

The sexual segment of the kidney of a tropical rattlesnake, Crotalus durissus (Reptilia, Squamata, Viperidae), and its relationship to seasonal testicular and androgen cycles

The sexual segment of the kidney (SSK) is a hypertrophied region of the nephron, which occurs in males of most squamate species that have been investigated, at least, during the active season. Many studies have shown that the SSK has a seasonal secretory cycle that could be correlated to the mating season, testicular activity, and androgen synthesis. However, to date, no study has investigated the presence of androgen receptors (AR) in cells of the SSK, nor the relation between the expression of AR, testosterone levels, and testicular condition. The SSK in Crotalus durissus corresponds to the distal segment of the nephron and presents a peak of hypertrophy during the period of testicular activity (spermatogenesis) and high testosterone levels, suggesting that seasonal variation of the SSK might be under the control of androgens. Testosterone concentrations and expression of AR varied seasonally with increased values for both parameters directly correlated to hypertrophy of the SSK. This study is, therefore, the first to target the SSK of a tropical snake and to establish a relationship between the secretory cycle of the SSK, testicular cycle, and levels of androgens. Furthermore, this study is the first to identify the presence of AR in the nucleus of the SSK cells.

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-1β, 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.

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.