Aliskiren Reduces the Adrenal Zona Glomerulosa Apoptosis and Autophagy in Wistar Rats with 2K1C Hypertension.

Hypertension is a disease classified as primary or secondary, manifested not only by elevation of blood pressure but also involved in structural and functional changes of target organs. Renal artery stenosis is a leading factor of secondary hypertension, and its progress is associated with overactivation of the renin-angiotensin-aldosterone system (RAAS). Aliskiren is a renin inhibiting drug that suppresses RAAS and culminates in decreased renin release, plasma angiotensin II concentration, and inhibition of aldosterone secretion. In this sense, the aim of the present study was to analyze the structural and ultrastructural morphophysiology of the adrenal glomerular zone, after treatment with aliskiren in Wistar rats with 2K1C hypertension. Parameters as structure and ultrastructure of the adrenal glomerular zone, cellular apoptosis, nuclear cell proliferation, and AT1 receptor expression were analyzed by immunostaining and electron microscopy. Our results showed that the hypertensive animals treated with aliskiren presented a reestablishment of AT1 receptor expression and decrease in apoptosis and autophagy. In addition, treatment with aliskiren improves the cell aspects in the adrenal glomerular zone, evidenced by ultrastructural analysis through preserved nuclei and well-developed mitochondria. Therefore, our evidence suggests that aliskiren has a beneficial effect on the adrenal glomerular zone remodeling in animals with renovascular hypertension.

Intranasal administration of budesonide-loaded nanocapsule microagglomerates as an innovative strategy for asthma treatment.

The co-existence with rhinitis limits the control of asthma. Compared with oral H1 receptor antagonists, intranasal corticosteroids have been demonstrated to provide greater relief of all symptoms of rhinitis and are recommended as first-line treatment for allergic rhinitis. Intrinsic limitations of nasal delivery, such as the presence of the protective mucous layer, the relentless mucociliary clearance, and the consequent reduced residence time of the formulation in the nasal cavity, limit budesonide efficacy to the treatment of local nasal symptoms. To overcome these limitations and to enable the treatment of asthma via nasal administration, we developed a budesonide-loaded lipid-core nanocapsule (BudNC) microagglomerate powder by spray-drying using a one-step innovative approach. BudNC was obtained, as a white powder, using L-leucine as adjuvant with 75 ± 6% yield. The powder showed a bimodal size distribution curve by laser diffraction with a principal peak just above 3 µm and a second one around 0.45 µm and a drug content determined by HPLC of 8.7 mg of budesonide per gram. In vivo after nasal administration, BudNC showed an improved efficacy in terms of reduction of immune cell influx; production of eotaxin-1, the main inflammatory chemokine; and arrest of airways remodeling when compared with a commercial budesonide product in both short- and long-term asthma models. In addition, data showed that the results in the long-term asthma model were more compelling than the results obtained in the short-term model. Graphical abstract.

Zika Virus Infects Human Placental Mast Cells and the HMC-1 Cell Line, and Triggers Degranulation, Cytokine Release and Ultrastructural Changes.

Zika virus (ZIKV) is an emergent arthropod-borne virus whose outbreak in Brazil has brought major public health problems. Infected individuals have different symptoms, including rash and pruritus, which can be relieved by the administration of antiallergics. In the case of pregnant women, ZIKV can cross the placenta and infect the fetus leading to congenital defects. We have identified that mast cells in the placentae of patients who had Zika during pregnancy can be infected. This led to our investigation on the possible role of mast cells during a ZIKV infection, using the HMC-1 cell line. We analyzed their permissiveness to infection, release of mediators and ultrastructural changes. Flow cytometry detection of ZIKV-NS1 expression 24 h post infection in 45.3% of cells showed that HMC-1 cells are permissive to ZIKV infection. Following infection, ß-hexosaminidase was measured in the supernatant of the cells with a notable release at 30 min. In addition, an increase in TNF-α, IL-6, IL-10 and VEGF levels were measured at 6 h and 24 h post infection. Lastly, different intracellular changes were observed in an ultrastructural analysis of infected cells. Our findings suggest that mast cells may represent an important source of mediators that can activate other immune cell types during a ZIKV infection, which has the potential to be a major contributor in the spread of the virus in cases of vertical transmission.

Probiotic treatment during neonatal age provides optimal protection against experimental asthma through the modulation of microbiota and T cells.

The incidence of allergic diseases, which increased to epidemic proportions in developed countries over the last few decades, has been correlated with altered gut microbiota colonization. Although probiotics may play a critical role in the restoration of gut homeostasis, their efficiency in the control of allergy is controversial. Here, we aimed to investigate the effects of probiotic treatment initiated at neonatal or adult ages on the suppression of experimental ovalbumin (OVA)-induced asthma. Neonatal or adult mice were orally treated with probiotic bacteria and subjected to OVA-induced allergy. Asthma-like symptoms, microbiota composition and frequencies of the total CD4+ T lymphocytes and CD4+Foxp3+ regulatory T (Treg) cells were evaluated in both groups. Probiotic administration to neonates, but not to adults, was necessary and sufficient for the absolute prevention of experimental allergen-induced sensitization. The neonatally acquired tolerance, transferrable to probiotic-untreated adult recipients by splenic cells from tolerant donors, was associated with modulation of gut bacterial composition, augmented levels of cecum butyrate and selective accumulation of Treg cells in the airways. Our findings reveal that a cross-talk between a healthy microbiota and qualitative features inherent to neonatal T cells, especially in the Treg cell subset, might support the beneficial effect of perinatal exposure to probiotic bacteria on the development of long-term tolerance to allergens.

Diethylcarbamazine: A potential treatment drug for pulmonary hypertension?

The present study demonstrated the potential effects of diethylcarbamazine (DEC) on monocrotaline (MCT)-induced pulmonary hypertension. MCT solution (600mg/kg) was administered once per week, and 50mg/kg body weight of DEC for 28days. Three C57Bl/6 male mice groups (n=10) were studied: Control; MCT28, and MCT28/DEC. Echocardiography analysis was performed and lung tissues were collected for light microscopy (hematoxylin-eosin and Masson's trichrome staining), immunohistochemistry (αSMA, FADD, caspase 8, caspase 3, BAX, BCL2, cytochrome C and caspase 9) western blot (FADD, caspase 8, caspase 3, BAX, BCL2, cytochrome C and caspase 9) and qRt-PCR (COL-1α and αSMA). Echocardiography analysis demonstrated an increase in the pulmonary arterial blood flow gradient and velocity in the systole and RV area in the MCT28 group, while treatment with DEC resulted in a significant reduction in these parameters. Deposition of collagen fibers and αSMA staining around the pulmonary arteries was evident in the MCT28 group, while treatment with DEC reduced both. Western blot analysis revealed a decrease in BMPR2 in the MCT28 group, in contrast DEC treatment resulted in a significant increase in the level of BMPR2. DEC also significantly reduced the level of VEGF compared to the MCT28 group. Apoptosis extrinsic and intrinsic pathway markers were reduced in the MCT28 group. After treatment with DEC these levels returned to baseline. The results of this study indicate that DEC attenuates PH in an experimental monocrotaline-induced model by inhibiting a series of markers involved in cell proliferation/death.

Papel do TNF-alfa na resposta inflamatória pulmonar causada por partículas de sílica em camundongos / Role of TNF-alfa in inflammatory response caused by silica particles in mice

A silicose é uma doença pulmonar crônica, de caráter ocupacional, que se desenvolve em decorrência da inalação de partículas de sílica cristalina e envolve a participação de uma ampla gama de mediadores inflamatórios e fibrogênicos. O TNF-alfa é uma citocina implicada em várias dinfunções de caráter inflamatório e fibrótico. Desta forma, no presente estudo investigamos a participação do TNF-alfa na silicose experimental murina, com especial ênfase sobre o comprometimento da função pulmonar e hiperreatividade das vias aéreas. A potencial correlação entre estes fenômenos e as alterações morfológicas no parênquima pulmonar foi igualmente analisada. Camundongos foram estimulados através de instilação intranasal de sílica (10 mg) e as análises realizadas em intervalos de tempo que variaram de 12 horas a 28 dias. Verificamos que camundongos silicóticos apresentaram aumento nos níveis basais de resistência e elastância pulmonar, em comparação aos animais controles. Quando da aerolização de concentrações crescentes com o agente broncoconstrictor metacolina, vimos que houve um significativo aumento na resposta de resistência e de elastância, na condição de silicose, fenômeno este também observado quando da provocação com serotonina. A análise morfológica, feita com base em técnicas clássicas de histologia, revelou a existência de um intenso infiltrado inflamatório em tempos iniciais (12 horas e 2 dias), seguido por aparecimento de granulomas em 7 dias e intensa resposta fibrótica e intensificação de número e tamanho de granuloma, 28 dias após a instilação com sílica. Buscando, então, avaliar o papel do TNF no quadro silicótico, em uma primeira etapa evidenciamos um aumento tanto na expressão de RNAm como na geração de TNF-alfa no tecido pulmonar nos animais silicóticos (em 7 e 28 dias), em comparação aos controles. De forma interessante, a instilação intrasanal de TNF-alfa em animais normais foi capaz de induzir um claro quadro de hiperreatividade das vias aéreas. Na sequência, verificamos que camundongos TNFR1 (menos/menos) silicóticos apresentaram níveis basais de resistência e elastância equivalentes àqueles dos animais TNFR1(mais/mais) instilados com salina, bem como uma marcada supressão da resposta de hiperreatividade das vias aéreas. Através da avaliação morfológica e morfométrica, notamos significativa inibição do infiltrado inflamatório e do processo de fibrogênese e de formação de granulomas nos animais TNFR1(menos/menos) silicóticos em comparação aos animais TNFR1(mais/mais) silicóticos. Em conclusão, tomados em conjunto nossos resultados mostram que o TNF-alfa parece desempenhar um papel relevante tanto no comprometimento da função pulmonar, bem como na resposta inflamatório/fibrogênica e na formação de granulomas, no modelo de silicose experimental murina. Podemos, ainda, sugerir que o TNF-alfa se coloca como um alvo terapêutico em potencial na busca por terapias anti-fibróticas a serem adotadas no caso de doenças pulmonares inflamatórias crônicas como a silicose.