University of Turku

About: University of Turku is a education organization based out in Turku, Finland. It is known for research contribution in the topics: Population & Galaxy. The organization has 16296 authors who have published 45124 publications receiving 1505428 citations. The organization is also known as: Turun yliopisto & Åbo universitet.

Promoting the clearance of neurotoxic proteins in neurodegenerative disorders of ageing

Abstract: Neurodegenerative disorders of ageing such as Alzheimer disease, Parkinson disease and Huntington disease are characterized by the presence of neurotoxic misfolded and aggregated proteins. One reason underlying the accumulation of these proteins is insufficient clearance by intracellular and extracellular pathways such as the autophagic–lysosomal network and the glymph system. This article reviews the potential for therapeutically enhancing the clearance of neurotoxic proteins to curtail the onset and slow the progression of neurodegenerative disorders of ageing. Neurodegenerative disorders of ageing (NDAs) such as Alzheimer disease, Parkinson disease, frontotemporal dementia, Huntington disease and amyotrophic lateral sclerosis represent a major socio-economic challenge in view of their high prevalence yet poor treatment. They are often called 'proteinopathies' owing to the presence of misfolded and aggregated proteins that lose their physiological roles and acquire neurotoxic properties. One reason underlying the accumulation and spread of oligomeric forms of neurotoxic proteins is insufficient clearance by the autophagic–lysosomal network. Several other clearance pathways are also compromised in NDAs: chaperone-mediated autophagy, the ubiquitin–proteasome system, extracellular clearance by proteases and extrusion into the circulation via the blood–brain barrier and glymphatic system. This article focuses on emerging mechanisms for promoting the clearance of neurotoxic proteins, a strategy that may curtail the onset and slow the progression of NDAs.

PASSCLAIM - gut health and immunity

Abstract: Background The gut and immune system form a complex integrated structure that has evolved to provide effective digestion and defence against ingested toxins and pathogenic bacteria. However, great variation exists in what is considered normal healthy gut and immune function. Thus, whilst it is possible to measure many aspects of digestion and immunity, it is more difficult to interpret the benefits to individuals of variation within what is considered to be a normal range. Nevertheless, it is important to set standards for optimal function for use both by the consumer, industry and those concerned with the public health. The digestive tract is most frequently the object of functional and health claims and a large market already exists for gut-functional foods worldwide. Aim To define normal function of the gut and immune system and describe available methods of measuring it. Results We have defined normal bowel habit and transit time, identified their role as risk factors for disease and how they may be measured. Similarly, we have tried to define what is a healthy gut flora in terms of the dominant genera and their metabolism and listed the many, varied and novel methods for determining these parameters. It has proved less easy to provide boundaries for what constitutes optimal or improved gastric emptying, gut motility, nutrient and water absorption and the function of organs such as the liver, gallbladder and pancreas. The many tests of these functions are described. We have discussed gastrointestinal well being. Sensations arising from the gut can be both pleasant and unpleasant. However, the characteristics of well being are ill defined and merge imperceptibly from acceptable to unacceptable, a state that is subjective. Nevertheless, we feel this is an important area for future work and method development. The immune system is even more difficult to make quantitative judgements about. When it is defective, then clinical problems ensure, but this is an uncommon state. The innate and adaptive immune systems work synergistically together and comprise many cellular and humoral factors. The adaptive system is extremely sophisticated and between the two arms of immunity there is great redundancy, which provides robust defences. New aspects of immune function are discovered regularly. It is not clear whether immune function can be "improved". Measuring aspects of immune function is possible but there is no one test that will define either the status or functional capacity of the immune system. Human studies are often limited by the ability to sample only blood or secretions such as saliva but it should be remembered that only 2% of lymphocytes circulate at any given time, which limits interpretation of data. We recommend assessing the functional capacity of the immune system by: measuring specific cell functions ex vivo measuring in vivo responses to challenge, e. g. change in antibody in blood or response to antigens determining the incidence and severity of infection in target populations during naturally occurring episodes or in response to attenuated pathogens.

Photosynthesis, photorespiration, and light signalling in defence responses

Abstract: Visible light is the basic energetic driver of plant biomass production through photosynthesis. The constantly fluctuating availability of light and other environmental factors means that the photosynthetic apparatus must be able to operate in a dynamic fashion appropriate to the prevailing conditions. Dynamic regulation is achieved through an array of homeostatic control mechanisms that both respond to and influence cellular energy and reductant status. In addition, light availability and quality are continuously monitored by plants through photoreceptors. Outside the laboratory growth room, it is within the context of complex changes in energy and signalling status that plants must regulate pathways to deal with biotic challenges, and this can be influenced by changes in the highly energetic photosynthetic pathways and in the turnover of the photosynthetic machinery. Because of this, defence responses are neither simple nor easily predictable, but rather conditioned by the nutritional and signalling status of the plant cell. This review discusses recent data and emerging concepts of how recognized defence pathways interact with and are influenced by light-dependent processes. Particular emphasis is placed on the potential roles of the chloroplast, photorespiration, and photoreceptor-associated pathways in regulating the outcome of interactions between plants and pathogenic organisms.

Male pheromone-stimulated neurogenesis in the adult female brain: possible role in mating behavior

Abstract: The regulation of female reproductive behaviors may involve memories of male pheromone signatures, formed in part by neural circuitry involving the olfactory bulb and hippocampus. These neural structures are the principal sites of adult neurogenesis; however, previous studies point to their independent regulation by sensory and physiological stimuli. Here we report that the pheromones of dominant (but not subordinate) males stimulate neuronal production in both the olfactory bulb and hippocampus of female mice, which are independently mediated by prolactin and luteinizing hormone, respectively. Neurogenesis induced by dominant-male pheromones correlates with a female preference for dominant males over subordinate males, whereas blocking neurogenesis with the mitotic inhibitor cytosine arabinoside eliminated this preference. These results suggest that male pheromones are involved in regulating neurogenesis in both the olfactory bulb and hippocampus, which may be important for female reproductive success.

Carotid Artery Intima-Media Thickness in Children With Type 1 Diabetes

Abstract: Postmortem studies have shown a relationship between diabetic state and atherosclerotic arterial lesions in adolescents. The aim of the present study was to determine the presence of increased subclinical atherosclerosis (measured as carotid intima-media thickness [IMT]) and its risk factors, including lipoprotein oxidation, in children with type 1 diabetes. We measured carotid IMT using high-resolution ultrasound in 85 children (mean age, 11 ± 2 years): 50 with type 1 diabetes (mean duration, 4.4 ± 3.0 years) and 35 healthy control subjects matched for age, sex, and body size. The susceptibility of LDL to oxidation was determined by measuring the formation of conjugated dienes induced by Cu2+ in 42 children (21 with diabetes and 21 control subjects). The mean carotid IMT was increased in children with diabetes (0.47 ± 0.04 vs. 0.42 ± 0.04 mm; P < 0.0001). Total cholesterol and LDL cholesterol concentrations were similar between the groups, but the children with diabetes had increased LDL diene formation rate (0.49 ± 0.06 vs. 0.45 ± 0.07 μmol/min; P < 0.05), suggesting increased in vitro LDL oxidizability. In a multivariate model for all subjects, the independent correlates for IMT were the diabetic state ( P < 0.001), LDL cholesterol level ( P < 0.001), and systolic blood pressure ( P < 0.001). In children with diabetes but not in control subjects, LDL oxidizability correlated significantly with mean IMT ( r = 0.47, P < 0.05), and this relationship remained significant after controlling for LDL cholesterol level. We conclude that type 1 diabetes is an independent risk factor for increased carotid IMT in children. These data also suggest that increased oxidative modification of LDL may be related to early structural atherosclerotic vascular changes in children with diabetes.