Granulosa cell metabolism and the assessment of oocyte quality in IVF

The progesterone production of the granulosa cells of the cumulus– oocyte complex correlates very well with the cleavagepotential of embryos in an IVF system. The method is simpleand can be easily performed by any laboratory associated withIVF. Furthermore, high intratubal progesterone levels in theimmediate post-ovulatory period are probably important in prolongingthe intra-ampullary residence of the oocyte or embryo untilthe uterine endometnum is optimal for implantation.     

Ultrastructural parameters of fertile cryopreserved human sperm.

Two hundred and forty-four cryopreserved semen samples were used for artificial insemination by donor (AID). All samples were examined for motility and concentration. Thirty of the samples resulted in pregnancies. These samples were further examined ultrastructurally. There was no difference in sperm motility or concentration between the samples that did or did not result in a pregnancy. The ultrastructural characteristics of the samples that resulted in pregnancies revealed that only 15% of sperm (SD = 7.67) possessed normal morphology and had undamaged acrosomes after cryopreservation.     

Pregnancy without ovarian function. A case report

A 38-year-old nulliparous woman suffering from premature menopause was stimulated with oestradiol valerate in order to create an artificial endometrial cycle. Three oocytes were donated by a woman on an in vitro fertilisation cycle and were inseminated with the patient's husband's sperm. These were then transferred into the patient's uterus after the endometrium had been primed with progesterone to change it to the secretory phase. Pregnancy resulted and proceeded well. Gestation was terminated at the 34th week by caesarean section and 2 healthy boys and 1 girl were delivered.     

A sensitive gas chromatography-mass spectrometry assay reveals increased levels of monohydroxyeicosatetraenoic acid isomers in human plasma after extracorporeal photoimmunotherapy and under in vitro ultraviolet A exposure

Extracorporeal photoimmunotherapy (photopheresis) is a highly effective therapy in the treatment of various disorders. Although extracorporeal photoimmunotherapy has been successfully used for more than 10 y, its mechanism of action is still unclear. The formation of reactive oxygen species have been implicated in extracorporeal photoimmunotherapy, but malonyl dialdehyde as a marker of systemic lipid peroxidation did not increase significantly during treatment. To investigate further the involvement of reactive oxygen species in extracorporeal photoimmunotherapy, we have introduced a highly sensitive negative ion gas chromatography-mass spectrometry based method for quantitating oxygenated arachidonic acid isomers (hydroxyeicosatetraenoic acids) in plasma samples of patients treated with extracorporeal photoimmunotherapy. In the plasma of healthy volunteers pmole amounts of 2-, 3-, 5-, 8-12-, and 15-hydroxyeicosatetraenoic acid were detected and we observed a dose-dependent augmentation in these metabolites when the blood was irradiated with increasing doses of ultraviolet A in the presence of the photosensitizer 8-methoxypsoralen. Analysis of plasma samples obtained from patients before and after extracorporeal photoimmunotherapy revealed a characteristic increase in total hydroxyeicosatetraenoic acid levels, particularly of 5-hydroxyeicosatetraenoic acid which contributed 80% to the sum of all hydroxyeicosatetraenoic acid isomers. Chiral phase high-performance liquid chromatography indicated almost equal amounts of 5S- and 5R-hydroxyeicosatetraenoic acid suggesting that the majority of lipid peroxidation products are formed via nonenzymatic oxidation reactions.     

Inhibitors of dipeptidyl peptidase IV and aminopeptidase N target major pathogenetic steps in acne initiation

Acne is a chronic disease hallmarked by sebaceous hyperplasia, follicular hyperkeratosis, and inflammation. Parallel targeting of these factors is required to treat acne effectively. Inhibitors of dipeptidyl peptidase IV (DP IV) and aminopeptidase N (APN) show strong anti-inflammatory effects on immune cells and therapeutic efficacy in autoimmune disorders. Our investigation focused on the expression and functional relevance of these ectopeptidases in three cell types which exhibit an altered phenotype in early acne lesions. We showed for the first time expression of DP IV and APN on human sebocytes. In the SZ95 sebocyte cell line, the DP IV inhibitors Lys[Z(NO2)]-thiazolidide and Lys[Z(NO2)]-pyrrolidide and the APN inhibitors actinonin and bestatin suppressed proliferation, enhanced terminal differentiation, and slightly decreased total neutral lipid production. The anti-inflammatory and differentiation-restoring cytokine IL-1 receptor antagonist was significantly upregulated in SZ95 sebocytes and the HaCaT keratinocyte cell line in the presence of inhibitors. Furthermore, the inhibitors suppressed proliferation and IL-2 production of Propionibacterium acnes-stimulated T cells ex vivo and enhanced the expression of the immunosuppressive cytokine transforming growth factor-beta1. Our data provide first evidence for a functional role of DP IV and APN in the sebaceous gland apparatus and for their inhibitors, used alone or in combination, as completely new substances possibly affecting acne pathogenesis in a therapeutic manner.     

The role of superoxide dismutase and alpha-tocopherol in the development of seizures and kindling induced by pentylenetetrazol - influence of the radical scavenger alpha-phenyl-N-tert-butyl nitrone

Previous experiments have shown that the generation of free hydroxyl radicals in rat brain homogenates is increased following pentylenetetrazol (PTZ) kindling. The present study was performed in order to evaluate the involvement of endogeneous radical defence systems as the superoxide dismutase (SOD) and the level of alpha-tocopherol, an important lipid-soluble and membrane-bound antioxidant in brain homogenate of rats after acute seizure and kindling induced by PTZ. The activities of the total SOD were significantly reduced after acute seizure and tend towards an enhancement in kindled animals. Western blot analysis shows an upregulation of Mn-SOD in rat brain homogenates after kindling. The level of the chain-breaking antioxidant alpha-tocopherol was reduced in acutely convulsing rats and was not modified in kindled rats. Second, we studied the influence of exogeneously supplied radical scavenger alpha-phenyl-N-tert-butyl-nitrone (PBN) on seizure and kindling following PTZ treatment. After a single injection of PTZ at a dose evoking clonic-tonic seizures, PBN did not modify either the formation of free hydroxyl radicals measured by the levels of 2,3-dihydroxybenzoic acid (DHBA) and 2,5-DHBA or the susceptibility to PTZ. In the kindling group, subchronic treatment with PBN (over a period of 4 weeks) prevented the increase in the formation of free hydroxyl radicals, and the susceptibility to PTZ was transiently decreased during the development of kindling, but PBN did not influence the susceptibility to PTZ in fully kindled rats. Pretreatment with PBN increased the activities of total SOD and the protein content of Mn-SOD and decreased the level of alpha-tocopherol in comparison to saline controls. The results suggest that the formation of free hydroxyl radicals is not reflected by an enhanced susceptibility to PTZ classified according to the modified RACINE scale. Additionally, it may be assumed that the increased generation of hydroxyl radicals in kindled animals is not primary caused by an exhaustion of both the defence systems measured. Adaptive mechanisms, as the induction of Mn-SOD, may be taken into consideration to counteract oxidative stress-mediated free radical formation.     

Oxidative stress in cardio renal anemia syndrome: correlations and therapeutic possibilities

Cardiovascular injury has been shown to be the most critical factor affecting quality of life and mortality in patients suffering from chronic renal failure. Oxidative stress has been thought to be an important risk factor for cardiovascular disorders. As oxidative stress parameters with high cardiovascular risk factor 4-hydroxynonenal and other aldehydic lipid peroxidation products, F2-isoprostanes, homocysteine, and cholesterol oxidation products were measured in chronic renal failure patients. 4-Hydroxynonenal and some cholesterol oxidation products correlated well with the degree of renal anemia. F2-isoprostane levels were related to inflammation, whereas homocysteine was increased due to malnutrition. Further, cholesterol oxidation products correlated well with the consumption of lipophilic antioxidants such as alpha-tocopherol. There was an almost linear correlation between the left ventricular mass index and 4-hydroxynonenal. Both parameters furthermore showed an inverse relationship to hemoglobin concentration. The correction of renal anemia by means of erythropoietin therapy led to an efficient strengthening of the antioxidative defence system. The improvement of the antioxidative capacity is of complex nature comprising both enzymatic pathways and low molecular antioxidants. The correction of renal anemia with its well documented reduction of the cardiovascular risk can be regarded as an antioxidative therapy, demonstrating the clinical efficiency of antioxidative protection in patients with chronic renal failure.     

Differential Oxidative Injury in Extrapancreatic Tissues During Experimental Pancreatitis

Oxidative stress is considered to be a pathogenic factor for multisystem organ failure during acute pancreatitis. Infusion of 3% and 5% sodium taurocholate into the pancreatic duct of rats resulted in a 24-hr lethality of 8% and 82%, respectively. Kidney tissue showed a long-lasting significant elevation of malondialdehyde (lipid peroxidation). Only small amounts of this aldehyde were formed in the liver. In the lung malondialdehyde was increased during the first 6 hr after pancreatitis induction. Malondialdehyde levels were not different for pancreatitis initiated by 3% or 5% taurocholate. Protein-bound carbonyls (protein oxidation) in the tissues were not significantly changed at any time point. However, after infusion of 5% taurocholate, lung proteins were oxidatively modified by the product of lipid peroxidation, 4-hydroxynonenal. Another parameter characteristic for pancreatitis with high lethality was the high number of neutrophils in the lungs. We conclude that oxidative stress is important for the injury of extrapancreatic tissues during pancreatitis, but survival is determined by the degree of systemic inflammation.