A proline derivative-enriched methanol fraction from Sideroxylon obtusifolium leaves (MFSOL) stimulates human keratinocyte cells and exerts a healing effect in a burn wound model

It was previously demonstrated that the methanol fraction of Sideroxylon obtusifolium (MFSOL) promoted anti-inflammatory and healing activity in excisional wounds. Thus, the present work investigated the healing effects of MFSOL on human keratinocyte cells (HaCaT) and experimental burn model injuries. HaCaT cells were used to study MFSOL's effect on cell migration and proliferation rates. Female Swiss mice were subjected to a second-degree superficial burn protocol and divided into four treatment groups: Vehicle, 1.0% silver sulfadiazine, and 0.5 or 1.0% MFSOL Cream (CrMFSOL). Samples were collected to quantify the inflammatory mediators, and histological analyses were performed after 3, 7, and 14 days. The results showed that MFSOL (50 μg/mL) stimulated HaCaT cells by increasing proliferation and migration rates. Moreover, 0.5% CrMFSOL attenuated myeloperoxidase (MPO) activity and also stimulated the release of interleukin (IL)-1β and IL-10 after 3 days of treatment. CrMFSOL (0.5%) also enhanced wound contraction, promoted improvement of tissue remodeling, and increased collagen production after 7 days and VEGF release after 14 days. Therefore, MFSOL stimulated human keratinocyte (HaCaT) cells and improved wound healing via modulation of inflammatory mediators of burn injuries.

α, ß-Amyrin prevents steatosis and insulin resistance in a high-fat diet-induced mouse model of NAFLD via the AMPK-mTORC1-SREBP1 signaling mechanism

Nonalcoholic fatty liver disease (NAFLD), characterized by hepatosteatosis and steatohepatitis, is intrinsically related to obesity. Our previous study reported on the anti-obese activity of α,β-amyrin (AMY), a pentacyclic triterpene isolated from Protium heptaphyllum. This study investigated its ability to prevent fatty liver and the underlying mechanism using the mouse model of NAFLD. NAFLD was induced in male Swiss mice fed a high fat diet (HFD) for 15 weeks. The controls were fed a normal chow diet (ND). The mice were simultaneously treated with AMY at 10 and 20 mg/kg or fenofibrate at 50 mg/kg. Lipid levels along with metabolic and inflammatory parameters were assessed in liver and serum. The liver sections were histologically examined using H&E staining. RT-qPCR and western blotting assays were performed to analyze signaling mechanisms. Mice fed HFD developed severe hepatic steatosis with elevated triglycerides and lipid droplets compared with ND controls. This was associated with a decrease in AMP-activated protein kinase (AMPK) activity, an increase of mechanistic target of rapamycin complex 1 (mTORC1) signaling, and enhanced sterol regulatory element binding protein 1 (SREBP1) expression, which have roles in lipogenesis, inhibition of lipolysis, and inflammatory response. AMY treatment reversed these signaling activities and decreased the severity of hepatic steatosis and inflammatory response, evidenced by serum and liver parameters as well as histological findings. AMY-induced reduction in hepatic steatosis seemed to involve AMPK-mTORC1-SREBP1 signaling pathways, which supported its beneficial role in the prevention and treatment of NAFLD.

Cicatrização da musculatura reto-abdominal em coelhos submetidos à laparorrafia com fios de sutura à base de quitosana, categute cromado e poliglactina 910 / [Healing of the rectus abdominis muscle in rabbits submitted to laparorrhaphy with suture-based chitosan, chromic catgut and polyglactin 910]

Objetivou-se, com este estudo, avaliar o processo de cicatrização da musculatura reto-abdominal em coelhos submetidos à laparorrafia, utilizando-se o fio de sutura à base de quitosana, comparando-o aos fios de categute cromado e poliglactina 910. Foram utilizados 24 coelhos adultos, divididos aleatoriamente em quatro grupos: quitosana e categute 15 dias (QC-15dias), quitosana e categute 30 dias (QC-30 dias), quitosana e poliglactina 910 15 dias (QP-15 dias) e quitosana e poliglactina 910 30 dias (QP-30 dias). Cada grupo foi composto por seis coelhos, nos quais foram realizadas duas incisões, uma do lado direito e outra do lado esquerdo e, posteriormente, a laparorrafia, com o fio de quitosana de um lado e o categute cromado ou poliglactina 910 do outro. Realizou-se análise clínico-cirúrgica, histológica e avaliação de achados de necropsia, além de testes de citotoxicidade e de mecânica no fio de quitosana. Ele apresentou baixa resistência mecânica e citotóxica. O fio de quitosana não proporcionou uma cicatrização satisfatória em coelhos, pois desencadeou uma resposta inflamatória acentuada.(AU)

The objective of this study was to evaluate the healing process of the recto-abdominal muscles in rabbits submitted to laparorrhaphy using chitosan-based suture yarn, comparing it to chrome catgut and polyglactin 910 yarns. Twenty-four adult rabbits were divided in to four random groups: chitosan and polyglactin 910 15 days (QP-15 days) and chitosan and polyglactin 910 30 days (QC-30 days), chitosan and polyglactin 910 15 days (QP-15 days) QP-30 days). Each group consisted of six rabbits, in which two incisions were made, one on the right side and one on the left side, and later the laparorraphy with the chitosan yarn on one side and chromed catgut or polyglactin 910 on the other. Clinical-surgical, histological and necropsy findings were evaluated, as well as cytotoxicity and mechanical tests on the chitosan wire. It presented low mechanical and cytotoxic resistance. Chitosan thread did not provide satisfactory healing in rabbits, as it triggered a marked inflammatory response.(AU)

Avaliação biomecânica e dimensional do fio de sutura à base de quitosana / Biomechanics and dimensional evaluation of the suture based on chitosan

A resistência à tração e o diâmetro são características de grande importância na avaliação da qualidade de fios de sutura, estando relacionados à capacidade destes de suportar o estresse promovido pelas forças atuantes em determinados tecidos. Desta forma, objetivou-se com este estudo avaliar as propriedades mecânica e dimensional de fios de sutura à base de quitosana, comparando-as com as preconizadas pela norma NBR 13904/2003. Tais propriedades foram avaliadas usando-se uma máquina de ensaio universal e um micrômetro digital. Os parâmetros mecânico e dimensional analisados foram a resistência quanto à tração, a deformação, bem como o diâmetro, respectivamente. O valor médio do diâmetro dos fios de quitosana apresentou variação e observou-se resistência à tração ligeiramente abaixo da norma preconizada, com rápida deformação. O fio de quitosana, na forma em que foi produzido, apresentou variabilidade dimensional e baixa resistência à tração, havendo a necessidade de melhorias no método de fabricação dele.(AU)

Tensile strength and diameter are very important characteristics in assessing the quality of suture, being related to their ability to withstand the stress caused by forces acting in certain tissues. Thus, the aim of this study was to evaluate the mechanical and dimensional properties of chitosan-based suture, comparing them with those recommended by the NBR 13904/2003. These properties were evaluated by using a universal testing machine and a digital micrometer. The mechanical and dimensional parameters analyzed were resistance to traction, deformation and diameter, respectively. The average diameter of the chitosan showed variation and yarn tensile strength was observed slightly below the recommended standard, with rapid deformation. The chitosan yarn in the form in which it was produced, presented dimensional variability and low tensile strength, there is a need for improvements in the method of manufacturing the same.(AU)

In vivo growth-inhibition of Sarcoma 180 by piplartine and piperine, two alkaloid amides from Piper

Piplartine {5,6-dihydro-1-[1-oxo-3-(3,4,5-trimethoxyphenyl)-2-propenyl]-2(1H)pyridinone} and piperine {1-5-(1,3)-benzodioxol-5-yl)-1-oxo-2,4-pentadienyl]piperidine} are alkaloid amides isolated from Piper. Both have been reported to show cytotoxic activity towards several tumor cell lines. In the present study, the in vivo antitumor activity of these compounds was evaluated in 60 female Swiss mice (N = 10 per group) transplanted with Sarcoma 180. Histopathological and morphological analyses of the tumor and the organs, including liver, spleen, and kidney, were performed in order to evaluate the toxicological aspects of the treatment with these amides. Administration of piplartine or piperine (50 or 100 mg kg-1 day-1 intraperitoneally for 7 days starting 1 day after inoculation) inhibited solid tumor development in mice transplanted with Sarcoma 180 cells. The inhibition rates were 28.7 and 52.3 percent for piplartine and 55.1 and 56.8 percent for piperine, after 7 days of treatment, at the lower and higher doses, respectively. The antitumor activity of piplartine was related to inhibition of the tumor proliferation rate, as observed by reduction of Ki67 staining, a nuclear antigen associated with G1, S, G2, and M cell cycle phases, in tumors from treated animals. However, piperine did not inhibit cell proliferation as observed in Ki67 immunohistochemical analysis. Histopathological analysis of liver and kidney showed that both organs were reversibly affected by piplartine and piperine treatment, but in a different way. Piperine was more toxic to the liver, leading to ballooning degeneration of hepatocytes, accompanied by microvesicular steatosis in some areas, than piplartine which, in turn, was more toxic to the kidney, leading to discrete hydropic changes of the proximal tubular and glomerular epithelium and tubular hemorrhage in treated animals.