Daily serum and salivary BDNF levels correlate with morning-evening personality type in women and are affected by light therapy.

INTRODUCTION: BDNF is present in human serum and its level changes have been used as a marker of antidepressant efficacy in some psychiatric disorders. In addition, the positive effects of light therapy on major depression suggest that circadian-regulated factors should be taken into account in the management of mood disorders. The aim of the present study was to test ultradian fluctuations in serum and salivary BDNF levels and their interaction with light therapy in a sample of healthy women. METHODS: The study included 16 young women. Psychopathological status and chronotype traits were assessed by SPAQ, BDI, STAI, TAS, and MEQ. Standard light treatment protocol was applied. Serum and saliva were collected at 8.00, 13.00 and 20.00 hrs on the same day and at the end of light therapy. RESULTS: BDNF levels declined over the course of the day both in serum and saliva, and a correlation between diurnal BDNF trend and personality traits and habits characterizing the morning and evening types in healthy women was found. CONCLUSIONS: The present study is one of the first to show measurable BDNF in human saliva and to demonstrate its daily fluctuations in both saliva and serum of healthy young women. The correlation between diurnal changes in BDNF and the personality traits associated with body rhythms corroborates the notion that salivary BDNF may be a useful biomarker for stress-related research and different clinical investigations.

NGF and NGF-receptor expression of cultured immortalized human corneal endothelial cells.

PURPOSE: Several growth factors, including nerve growth factor (NGF) and vascular endothelial growth factor (VEGF), play an important role in the homeostasis of the ocular surface. The involvement of both these growth factors in the pathophysiology of intraocular tissues has been extensively investigated. Despite the expression of NGF receptors by corneal endothelium, to date the role of NGF on the endothelial cell remains to be determined. Using a clonal cell line of human corneal endothelial cells, the aim of this study was to investigate the expression of the NGF-receptor and the potential partnership of NGF and VEGF in maintaining cell viability in vitro. METHODS: A human endothelial cell line (B4G12), was cultured under serum-free conditions as previously described with and without addition of different concentrations of NGF, anti-NGF-antibody (ANA), or VEGF for 4 days and these cells were used for immuno-istochemical, biochemical, and molecular analyses. RESULTS: NGF induces overexpression of NGF-receptors and synthesis and release of VEGF by endothelial cells and these cells are able to produce and secrete NGF. CONCLUSIONS: These observations indicate that human corneal endothelial cells are receptive to the action of NGF and that these cells may regulate NGF activity through autocrine/paracrine mechanisms.

Nerve growth factor in the developing and adult lacrimal glands of rat with and without inherited retinitis pigmentosa.

PURPOSE: In the present study, we investigated lacrimal function and presence of the neurotrophin nerve growth factor (NGF) and its receptors in the lacrimal gland (LG) of normal rats and rats with inherited retinitis pigmentosa (IRP). MATERIALS AND METHODS: After anesthesia, modified Schirmer tests were performed on IRP rats and Sprague Dawley (SD) rats to measure tear function. LGs of developing and adult IRP and SD rats were removed and used for histological, immunohistochemical, and biochemical analyses. RESULTS: The results showed that basal tear secretion is reduced in IRP rats as compared with SD rats. NGF and NGF receptors are expressed in the LG of both rat strains. In SD rats, these NGF markers are low during early life and more elevated in adult life. Conversely in rats with IRP, NGF and its receptors decreased in adult life. CONCLUSIONS: The role of NGF in maintaining ocular surface integrity is well known. The observations of this study further support the hypothesis that neurotrophins play a role in modulating tear secretion and probably in preventing the deleterious effects of dry eye. This hypothesis is presented and discussed.

Adipose tissue-derived nerve growth factor and brain-derived neurotrophic factor: results from experimental stress and diabetes.

Recently, adipobiology (adiposcience) became a focus of numerous studies showing that the adipose tissue is the body's largest endocrine and paracrine organ producing multiple signaling proteins collectively designated adipokines; at present these include more than hundred proteins. However, studies on adipobiology of neurotrophins have recently emerged, nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) being examples of adipose-derived neurotrophins. Here we present data showing that NGF and BDNF are expressed in both white and brown adipose tissue following experimental stress (in mice) and in type 1 diabetes (in rats). We suggest that both neurotrophic and metabotrophic potentials of NGF and BDNF may be involved in the molecular mechanism of stress and diabetes and consequently, in the pathogenesis of cardiometabolic diseases.

Hepatocyte growth factor, vascular endothelial growth factor, glial cell-derived neurotrophic factor and nerve growth factor are differentially affected by early chronic ethanol or red wine intake.

Ethanol intake during pregnancy and lactation induces severe changes in brain and liver throughout mechanisms involving growth factors. These are signaling molecules regulating survival, differentiation, maintenance and connectivity of brain and liver cells. Ethanol is an element of red wine which contains also compounds with antioxidant properties. Aim of the study was to investigate differences in hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), glial cell-derived neurotrophic factor (GDNF) and nerve growth factor (NGF) in brain areas and liver by ELISA of 1-month-old male mice exposed perinatally to ethanol at 11 vol.% or to red wine at same ethanol concentration. Ethanol was administered before and during pregnancy up to pups' weaning. Ethanol per se elevated HGF in liver and cortex, potentiated liver VEGF, reduced GDNF in the liver and decreased NGF content in hippocampus and cortex in the offspring. We did not find changes in HGF or NGF due to red wine exposure. However, we revealed elevation in VEGF levels in liver and reduced GDNF in the cortex of animals exposed to red wine but the VEGF liver increase was more marked in animals exposed to ethanol only compared to the red wine group. In conclusion the present findings in the mouse show differences in ethanol-induced toxicity when ethanol is administered alone or in red wine that may be related to compounds with antioxidant properties present in the red wine.

Glaucoma alters the expression of NGF and NGF receptors in visual cortex and geniculate nucleus of rats: effect of eye NGF application.

We investigated the effect of glaucoma (GL) on nerve growth factor (NGF) presence in two brain visual areas. Rats with elevated intraocular pressure (EIOP), induced by hypertonic saline injection in the episcleral vein, were treated with eye topical application of saline or NGF. Rats were subsequently sacrificed, and brain tissues were used for immunohistochemical, biochemical, and molecular analyses. We found that GL alters the basal level of NGF and NGF receptors in brain visual centers and that NGF eye application normalized these deficits. These findings demonstrate that the reduced presence of NGF can arise due to degenerative events in retinal and brain visual areas.

Axonal transport deficit in the optic nerve of rats with inherited retinitis pigmentosa and experimentally induced glaucoma.

BACKGROUND: Aim of this study was to investigate the retrograde axonal transport from optic nerve (ON) to retinal ganglion cell (RGC) in two animal models: in Royal College of Surgeons (RCS) rats, a rat model for retinal degeneration, and in a rat model for glaucoma induced by elevated intraocular pressure (IOP). METHODS: To carry out this study, dextran tetramethylrhodamine (DTMR--an hydrophilic neurotracer dye) was injected into the ON; 24 hrs later, the retina was removed and the number of labeled RGCs of the experimental rats was counted and compared. RESULTS: The results of these studies showed that the number of fluorescent-labeled RGCs in RCS rats and in rats with elevated IOP was reduced compared to the number of labeled RGCs of their respective controls. CONCLUSION: Our findings suggest that RCS rats are characterized not only by loss of photoreceptor cells but also by functional deficits of RGCs.