Search NEL Online

Comparative Study 2009; 30(1): 46-50 PubMed PMID: 19300398 Citation  Keywords:  Amyloid beta-Peptides:blood, Animals, Brain:metabolism, Guinea Pigs, Kidney:metabolism, Male, Orchiectomy, Testosterone:metabolism, Time Factors,.   

OBJECTIVES: The association between low testosterone levels and Alzheimer's disease (AD) amyloid beta-peptide (Abeta) metabolism was investigated in brain and kidney of guinea pigs.

METHODS: The expression of Abeta peptide in the brain and kidney was assessed by using the immunohistochemistry method.

RESULTS: No expression of Abeta was seen in both groups of animals. This negative staining was found until the fourth week following castration. The formation of Abeta in guinea pigs is perhaps not a short duration process and may undergo different metabolic pathway compare to humans.

CONCLUSION: castration was not associated with the formation of Abeta in the brain and kidneys during a 1-month period and might require a longer period of time....

Read abstract  Full text PDF

Journal Article 2008; 29(1): 75-79 PubMed PMID: 18283248 Citation  Keywords:  Aged, Aged, 80 and over, Alzheimer Disease:blood, Amyloid beta-Peptides:blood, Biomarkers:blood, Case-Control Studies, Female, Humans, Interleukin-10:blood, Interleukin-6:blood, Middle Aged, Tumor Necrosis Factor-alpha:blood,.   

: Alzheimer's disease (AD) belongs to a group of neurodegenerative disorders. It is characterized by irreversible and progressive memory loss accompanied with decline in other cognitive functions. At a microscopic level, the typical neuropathologic features, senile plaques and neurofibrillary lesions are found. The pathological processes lead to neuronal loss, synaptic dysfunction and inappropriate activity of neurotransmitters. The major constituent of senile plaques is abnormally aggregated beta amyloid protein. Beta amyloid (Abeta) is a short (40-42 amino acid) product of proteolysis of the transmembrane amyloid precursor protein (APP). Extracellular depositions of Abeta 1-42 may initiate a wide range of pathological processes including glia activation, neuroinflammation and neuronal apoptosis. There is convincing evidence that inflammatory response to accumulation of beta amyloid plays a pivotal role in the progression of neuropathological changes found in AD. Current research was directed at assessing beta amyloid, cytokines (IL-6, IL-10 and TNF alpha) plasma levels in women with AD. Hundred and twenty four women, aged between 59 to 86 years, were enrolled in the study. Amongst them 57 were diagnosed with AD (29 subjects in early stage and 28 subjects with moderate to severe stadium of disease) and 67 women without dementia were investigated as a control group. The lowest values of Abeta 1-42 were found in AD subjects in moderate to severe stage of disease as compared with the early stage of AD (p< 0.05) and the control group (p<0.01). Change in IL-6 values was significantly different between groups with the lowest values found in women without dementia. Both subset of AD patients demonstrated statistically enhanced IL-6 levels when compared with the control group (p<0.001, p<0.01 respectively for early and moderate/severe stage of AD). Moreover, our study revealed a trend to increase in TNF alfa and IL-10 values in AD. However, those differences were not statistically significant. In addition, we did not detect any correlations between plasma beta amyloid and investigated cytokines....

Read abstract  Full text PDF

Journal Article 2007; 28(3): 311-314 PubMed PMID: 17627268 Citation  Keywords:  Blood Pressure, Creatinine:blood, Female, Homocysteine:blood, Humans, Hypertension, Pregnancy-Induced:blood, Lipofuscin:blood, Oxidative Stress, Peptides:blood, Pregnancy,.   

OBJECTIVE: The aim of this study were to assess the levels of lipofuscin (parameter of oxidative stress), homocysteine (as a marker of vascular injury) and tissue specific antigen - TPS - (as a marker of cell proliferation) in relation to arterial pressure of pregnant woman.

STUDY DESIGN: Healthy pregnant women (n=18), women with mild 140/90=< RR<160/100 (n=19), and severe 160/100=
RESULTS: Mean duration of gestation was 34+/-5 weeks, and there were no differences between groups. Serum lipofuscin levels in mild form of pregnancy-induced hypertension were decreased comparing to normal pregnancy. Homocysteine levels were decreased and TPS levels increased in both mild and severe gestational hypertension.

CONCLUSION: Our results suggest overestimation of the role of oxidative stress and hyperhomocysteinemia in gestational hypertension....

Read abstract  Full text PDF

Journal Article 2005; 26(4): 293-296 PubMed PMID: 16135994 Citation  Keywords:  Adult, Energy Metabolism:physiology, Female, Humans, Insulin:blood, Intracellular Signaling Peptides and Proteins:blood, Leptin:blood, Middle Aged, Neuropeptide Y:blood, Neuropeptides:blood, Obesity:blood, Orexins, Radioimmunoassay,.   

OBJECTIVE: It has been reported that the peptides such as orexins, neuropeptide Y (NPY) and leptin may play an important role in the regulation of appetite and energy metabolism. The interaction between leptin, orexins and NPY, as well as between peptides and insulin and cortisol in the different nutritional states have been investigated in animals. However, at present this relationship is poorly understood in humans.

RESEARCH METHODS: Material consisted of 36 obese women and 16 lean women. Plasma orexin A, orexin B, neuropeptide Y (NPY), leptin, insulin concentrations were measured with RIA methods.

RESULTS: Plasma orexin A concentrations were significantly lower in obese women as compared with control group. Plasma orexin A was significantly lower in severe obesity (BMI > 40 kg/m2) than that in moderate obesity (BMI < 40 kg/m2). Plasma orexin B concentrations did not change. However, plasma NPY, leptin and insulin levels were markedly higher in obese women, especially in severe obesity.

CONCLUSIONS: Our results confirmed the thesis that orexin A, NPY, leptin play an important role in the regulation of energy metabolism in humans. In obesity the activity of these peptides is disturbed....

Read abstract  Full text PDF

Journal Article 2001; 22(5): 349-355 PubMed PMID: 11600877 Citation  Keywords:  Animals, Appetite Regulation:drug effects, Energy Metabolism:drug effects, Estradiol:blood, Female, Follicle Stimulating Hormone:blood, Galanin:blood, Hormones:blood, Leptin:analysis, Luteinizing Hormone:blood, Neuropeptide Y:blood, Neuropeptides:blood, P.   

OBJECTIVES: Some hormonal disturbances were demonstrated in starvation. Leptin, NPY and galanin play an important role in the control of appetite and in the mechanism of hormone release.

METHODS: In order to evaluate the effect of starvation on the relationship between leptin, neuropeptide Y (NPY) galanin and pituitary and gonadal hormones release, plasma leptin, NPY and galanin as well as serum LH, FSH, prolactin (PRL), estradiol, progesterone levels in non-starved female rats (in diestrus) and after 72 hrs of starvation were measured with RIA methods. Effects of leptin, NPY and galanin administration on pituitary and gonadal hormones were investigated in vivo and in vitro experiments.

RESULTS: Plasma leptin, NPY and galanin as well as serum estradiol and progesterone concentrations were significantly lower in starved rats as compared with non-starved rats. However serum prolactin level was significantly higher in starved rats. Opposite effects after leptin and NPY administration on hormone release in vivo and in vitro experiments were observed in non-starved rats. However, in starved rats we did not find changes in pituitary and gonadal hormones release after leptin, NPY and galanin injection or the hormonal response was blunted.

CONCLUSIONS: 1) The disturbances in neuropeptides activity and in hormones release were observed in starvation. 2) Leptin, NPY and galanin have direct and indirect effects on pituitary and gonadal hormones release. 3) In starvation the hormonal response to leptin, NPY and galanin is impaired....

Read abstract  Full text PDF