Nutritional imbalance underlies many disease processes but can be very beneficial in certain cases; for instance, the antiepileptic action of a high fat and low carbohydrate ketogenic diet. Besides this therapeutic feature it is not clear how this abundant fat supply may affect homeostasis, leading to side effects. A ketogenic diet is used as anti-seizure therapy i.a. in tuberous sclerosis patients, but its impact on concomitant tumor growth is not known. To examine this we have evaluated the growth of renal lesions in Eker rats (Tsc2+/−) subjected to a ketogenic diet for 4, 6 and 8 months. In spite of existing opinions about the anticancer actions of a ketogenic diet, we have shown that this anti-seizure therapy, especially in its long term usage, leads to excessive tumor growth. Prolonged feeding of a ketogenic diet promotes the growth of renal tumors by recruiting ERK1/2 and mTOR which are associated with the accumulation of oleic acid and the overproduction of growth hormone. Simultaneously, we observed that Nrf2, p53 and 8-oxoguanine glycosylase α dependent antitumor mechanisms were launched by the ketogenic diet. However, the pro-cancerous mechanisms finally took the ascendency by boosting tumor growth.
PurposeEstradiol (E2)-loaded poly(L-lactide-co-glycolide-trimethylenecarbonate) (P(L-LA:GA:TMC)) rods with shape-memory were developed for the treatment of neurodegenerative diseases. Usefulness of the extrusion method in the obtaining process was also considered. The influence of structural and surface properties during hydrolytic degradation was developed. The possible therapeutic aspect of rods with E2 was determined.MethodsThe extruded rods were incubated in a PBS solution (pH 7.4, 37°C, 240 rpm). The amount of released E2 in vitro conditions was estimated by UV-VIS method. The following methods in the degradation of rods were applied: NMR, DSC, FTIR, GPC, SEM, and optical microscopy. Changes in water uptake and weight loss were also determined. In vivo study was performed on rats. Measurements of E2 level were performed before and after ovariectomy of rats using ELISA method. A sample of tissue adjacent to the site of the rod implantation was analysed under an optical microscope.ResultsA stable and steady degradation process ensured zero-order release of E2. The in vivo study indicated a significant increase in the E2 level in serum after ovariectomy. Moreover, structural and surface features indicated that the extrusion method was appropriate for obtaining E2-loaded rods.ConclusionsShape-memory P(L-LA:GA:TMC) rods with E2 are an adequate proposal for further research in the field of neurological disorders.
In the subarachnoid hemorrhage (SAH) blood mixes with cerebrospinal fluid, what starts immunoinflammatory processes - increased synthesis of proinflammatory cytokines, and formation of reactive oxygen species (ROS), resulting in pre-activation of different populations of peripheral leukocytes. Migration of leukocytes to the brain parenchyma through broken blood brain barrier may produce extra brain tissue injury besides of that resulting from SAH. We examined in adult rats the effect of interleukin-1β (IL-1β) neutralization on secretion of cytokines as well as production of ROS in the course of SAH. SAH was produced by injection of 150 μL of autologous arterial blood into cisterna magna. In 50% of animals, IL-1beta activity was inhibited by intracerebroventricular administration of anti-rat IL-1β antibodies. Ninety minutes or 24 hrs following surgery, blood samples were drawn from the extraorbital plexus and centrifuged to obtain two leukocyte subpopulations - polymorphonuclear (PMN) and mononuclear (MN). The chemiluminescence, a hallmark of ROS synthesis, was measured in PMNs. In supernatants from MNs cultures, concentrations endothelin-1 (ET-1), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were assessed. SAH caused the increase ofn PMNs chemiluminescence as well as the increase of production of ET-1 and TNF-α by MNs but had no influence on IL-6 concentration. Neutralization of IL-1β resulted in significant decrease of chemiluminescence as well as concentration of both ET-1 and TNF-α, while IL-6 concentration was increased. These revealed an important role of IL-1β in the activation of peripheral leukocytes in the course of subarachnoid hemorrhage.
Dieta ketogeniczna jest dietą bardzo niskowęglowodanową i wysokotłuszczową indukującą wzmożoną produkcję ciał ketonowych, które stanowią alternatywne do glukozy źródło energii. Dieta ketogeniczna od prawie wieku wykorzystywana jest w terapii padaczki. W ostatnich latach obserwuje się wzrost zainteresowania naukowców dietą ketogeniczną w leczeniu także innych chorób, co związane jest z plejotropowym efektem jaki dieta ta wywiera na organizm w tym na procesy zapalne, stres oksydacyjny, gospodarkę energetyczną oraz komórkowe szlaki przekaźnictwa sygnału. Prowadzone są badania nad wykorzystaniem diety ketogenicznej w terapii m.in. otyłości, cukrzycy typu 2, oraz wspomagająco w leczeniu wybranych typów nowotworów i chorób neurologicznych. W artykule dokonano przeglądu badań klinicznych dotyczących możliwości stosowania diety ketogenicznej w leczeniu wybranych chorób oraz przedstawiono potencjalne mechanizmy warunkujące właściwości terapeutyczne tej diety. Opisano także procesy metaboliczne charakterystyczne dla stanu ketozy żywieniowej oraz przedyskutowano istotne praktyczne aspekty stosowania diety ketogenicznej.
Obesity cardiomyopathy increases the risk of heart failure and death. Obesity is curable, leading to the restoration of the heart phenotype, but it is not clear if there are any after-effects of obesity present after weight loss. We characterize the proteomic landscape of obesity cardiomyopathy with an evaluation of whether the cardiac phenotype is still shaped after weight loss. Cardiomyopathy was validated by cardiac hypertrophy, fibrosis, oversized myocytes, and mTOR upregulation in a rat model of cafeteria diet-induced developmental obesity. By global proteomic techniques (LC-MS/MS) a plethora of molecular changes was observed in the heart and circulation of obese animals, suggesting abnormal utilization of metabolic substrates. This was confirmed by increased levels of cardiac ACSL-1, a key enzyme for fatty acid degradation and decreased GLUT-1, a glucose transporter in obese rats. Calorie restriction and weight loss led to the normalization of the heart’s size, but fibrosis was still excessive. The proteomic compositions of cardiac tissue and plasma were different after weight loss as compared to control. In addition to morphological consequences, obesity cardiomyopathy involves many proteomic changes. Weight loss provides for a partial repair of the heart’s architecture, but the trace of fibrotic deposition and proteomic alterations may occur.
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