Cisplatin is a widely used chemotherapeutic drug, but its side effects are a major limiting factor. Nephrotoxicity occurs in one third of patients undergoing cisplatin treatment. The acute tubular injury caused by cisplatin often leads to a defective repair process, which translates into chronic renal disorders. In this way, cisplatin affects tubular cells, and maladaptive tubules regeneration will ultimately result in tubulointerstitial fibrosis. Kinins are well known for being important peptides in the regulation of inflammatory stimuli, and kinin B1 receptor deficiency and antagonism have been shown to be beneficial against acute cisplatin nephrotoxicity. This study aimed to analyze the effects of kinin B1 receptor deletion and antagonism against repeated cisplatin-induced chronic renal dysfunction and fibrosis. Both the deletion and the antagonism of B1 receptor exacerbated cisplatin-induced chronic renal dysfunction. Moreover, the inhibition of B1 receptor increased tubular injury and tubulointerstitial fibrosis after repeated treatment with cisplatin. The balance between M1/M2 macrophage polarization plays an important role in renal fibrosis. Kinin B1 receptor antagonism had no impact on M1 markers when compared to cisplatin. However, YM1, an M2 marker and an important molecule for the wound healing process, was decreased in mice treated with kinin B1 receptor antagonist, compared to cisplatin alone. Endothelin-1 levels were also increased in mice with B1 receptor inhibition. This study showed that kinin B1 receptor inhibition exacerbated cisplatin-induced chronic renal dysfunction and fibrosis, associated with reduced YM1 M2 marker expression, thus possibly affecting the wound healing process.

Avaliou-se o potencial acaricida in vitro do óleo da semente da andiroba (Carapa guianensis) sobre fêmeas ingurgitadas de Anocentor nitens (n=210) e Rhipicephalus sanguineus (n=140), coletadas manualmente, respectivamente, de equinos e de cães naturalmente infestados. Para o teste de imersão, empregaram-se cinco diluições do óleo de andiroba, 100%, 50%, 30%, 25% e 10%, em água destilada, utilizando-se tween 80 como dispersante. No teste com A. nitens, foram usadas três repetições para cada diluição, utilizando-se 10 fêmeas ingurgitadas para cada tratamento. No teste com R. sanguineus, usaram-se duas repetições, e formaram-se, ainda, dois grupos-controle para cada espécie de ixodídeo, um com água destilada e outro com tween 80 mais água destilada. Após os testes, as fêmeas foram mantidas em laboratório sob temperatura ambiente. Observou-se mortalidade das fêmeas ingurgitadas e redução de postura, neste caso, com ovos inférteis, demonstrando eficácia de 100% nas duas espécies em todas as diluições testadas. Os dados obtidos evidenciaram a potencialidade do uso do extrato de andiroba contra A. nitens e R. sanguineus.

In vitro acaricide potential of the oil from andiroba seed (Carapa guianensis) was evaluated on engorged females of Anocentor nitens (n=210) and Rhipicephalus sanguineus (n=140) manually collected, from horses and dogs naturally infested, respectively. Five dilutions, 100%, 50%, 30%, 25%, and 10% of andiroba seed oil in deionized water, using tween 80 as dispersant, were employed for the engorged females immersion test. For A. nitens test, three repetitions were made with each dilution, using 10 engorged females for each treatment, and two repetitions for R. sanguineus test. Two control groups were used for each tick species, one with deionized water and another one with tween 80 and deionized water. After the tests, the females were kept in the laboratory under room temperature. Engorged female mortality and oviposition reduction were observed with infertile eggs, showing 100% of efficacy in the two species in all tested dilutions. The obtained data demonstrated the potential use of andiroba seed extract against A. nitens and R. sanguineus.

O uso do fogo e de roçadeira para controle de plantas daninhas em pastagens tem se mostrado pouco efetivo. Já o uso de herbicidas sintéticos, embora mais eficaz no controle de plantas daninhas, tem sido questionado quanto ao impacto ambiental. Portanto, a busca de compostos naturais para possível utilização como herbicida é de fundamental importância. Esses fatos motivaram o presente estudo, que teve como objetivos isolar, identificar e caracterizar a atividade alelopática potencial de substâncias químicas produzidas por Myrcia guianensis (pedra-ume-caá). Foram analisados os efeitos potenciais alelopáticos de extratos brutos, partições, óleo essencial e das substâncias químicas isoladas (ácido gálico e ácido protocatecuico) sobre a germinação e o desenvolvimento da radícula e do hipocótilo das plantas daninhas Mimosa pudica (malícia) e Senna obtusifolia (mata-pasto) em pastagens. Os extratos brutos e as partições foram analisados em concentração de 1%; o óleo essencial, em concentrações de 1, 5, 10, 15 e 20 ppm; e as substâncias isoladas, em concentrações de 15, 30, 45 e 60 ppm. A espécie malícia se mostrou mais sensível aos efeitos alelopáticos dos extratos brutos e das partições. O óleo essencial inibiu a germinação da malícia e estimulou a germinação no mata-pasto. A atividade alelopática das substâncias químicas isoladas esteve associada à concentração, e a atividade mais intensa foi em 60 ppm.

The use of fire and mowing as weed methods have proved inefficient. Although more efficient, synthetic chemical herbicides are usually related to environmental problems. Thus, the search for natural herbicides has become a priority matter. Based on these facts, research was conducted on Myrcia guianensis (pedra-ume-caá) including the isolation and identification of chemical substances with allelophatic activity. The allelophatic effects of extracts, fractions, essential oils, and isolated chemical substances (gallic acid and protocatechuic acid) on germination and radicle and hypocotyl growth of weed species Mimosa pudica (malícia) and Senna obtusifolia (mata-pasto) were analyzed. Extracts and fractions were analyzed at a concentration of 1%, essential oils at 15, 30, 45, 60 ppm and the isolated chemical substances at 15, 30, 45, 60 ppm. Malicia showed more sensitivity to the allelophatic effects of extracts and fractions. The essential oil inhibited the germination of M. pudica but stimulated that of S. obtusifolia. The allelophatic effects of the chemical substances were concentration dependent and the strongest activity was observed at 60 ppm.