Effects of Lactoferrin on Oral and Throat Conditions under Low Humidity Environments: A Randomized, Double-Blind, and Placebo-Controlled Crossover Trial

To evaluate the effects of a single ingestion of bovine lactoferrin (bLF) on oral and throat conditions under a low-humidity environment. A randomized, double-blind, 2-sequence, 2-treatment, and 2-period placebo-controlled crossover trial was conducted. Healthy adult subjects orally ingested bLF dissolved in water, or placebo water, followed by exposure to low humidity (20 °C, 20% relative humidity (RH)) for 2 h. The primary endpoint was subjective oral and throat discomfort assessed by a visual analog scale (VAS), which positively correlated with the discomfort. Secondary endpoints were unstimulated whole salivary flow rate (UWSFR) and salivary immunoglobulin A (IgA) secretion rate. Overall, 40 subjects were randomly assigned to two sequences (20 each) and 34 were analyzed. The VAS values for oral and throat discomfort in the bLF treatment were significantly lower than in the placebo treatment, whereas UWSFR and IgA secretion rates were comparable between the two treatments. Adverse drug reactions were not observed. Subjective oral and throat discomfort associated with low humidity is suppressed by a single ingestion of bLF. Our findings demonstrate the novel use of bLF in a clinical situation that leverages its unique characteristics

Effects of Bovine Lactoferrin on the Maintenance of Respiratory and Systemic Physical Conditions in Healthy Adults—A Randomized, Double-Blind, Placebo-Controlled Trial

Objectives: We investigated the effects of bovine lactoferrin (LF) on the maintenance of the respiratory and systemic physical conditions. Methods: A randomized, double-blind, placebo-controlled trial was conducted. Healthy adults at Kyushu University of Health and Welfare ingested a placebo or bovine LF (200 mg/day) for 12 weeks. The primary endpoints were the total respiratory and systemic symptom scores. The secondary endpoint was the activity of plasmacytoid dendritic cells (pDCs) in peripheral blood. Results: A total of 157 subjects were randomized (placebo, n = 79; LF, n = 78), of whom, 12 dropped out. The remaining 145 participants were included in the full analysis set (placebo group, n = 77; LF group, n = 68). The total scores for respiratory and systemic symptoms during the intervention were significantly lower in the LF group than in the placebo group. The expression of CD86 and HLA-DR on pDCs was significantly higher in the LF group than in the placebo group at week 12. Adverse events were comparable between the groups, and no adverse drug reactions were observed. Conclusions: These results suggest that orally ingested LF supports the normal immune system via maintaining pDC activity, and maintains respiratory and systemic physical conditions in healthy adults

SOCS7-Derived BC-Box Motif Peptide Mediated Cholinergic Differentiation of Human Adipose-Derived Mesenchymal Stem Cells

Adipose-derived mesenchymal stem cells (ADMSCs) are a type of pluripotent somatic stem cells that differentiate into various cell types such as osteoblast, chondrocyte, and neuronal cells. ADMSCs as donor cells are used to produce regenerative medicines at hospitals and clinics. However, it has not been reported that ADMSCs were differentiated to a specific type of neuron with a peptide. Here, we report that ADMSCs differentiate to the cholinergic phenotype of neurons by the SOCS7-derived BC-box motif peptide. At operations for patients with neurological disorders, a small amount of subcutaneous fat was obtained. Two weeks later, adipose-derived mesenchymal stem cells (ADMSCs) were isolated and cultured for a further 1 to 2 weeks. Flow cytometry analysis for characterization of ADMSCs was performed with CD73, CD90, and CD105 as positive markers, and CD14, CD31, and CD56 as negative markers. The results showed that cultured cells were compatible with ADMSCs. Immunocytochemical studies showed naïve ADMSCs immunopositive for p75NTR, RET, nestin, keratin, neurofilament-M, and smooth muscle actin. ADMSCs were suggested to be pluripotent stem cells. A peptide corresponding to the amino-acid sequence of BC-box motif derived from SOCS7 protein was added to the medium at a concentration of 2 μM. Three days later, immunocytochemistry analysis, Western blot analysis, ubiquitination assay, and electrophysiological analysis with patch cramp were performed. Immunostaining revealed the expression of neurofilament H (NFH), choline acetyltransferase (ChAT), and tyrosine hydroxylase (TH). In addition, Western blot analysis showed an increase in the expression of NFH, ChAT, and TH, and the expression of ChAT was more distinct than TH. Immunoprecipitation with JAK2 showed an increase in the expression of ubiquitin. Electrophysiological analysis showed a large holding potential at the recorded cells through path electrodes. The BC-box motif peptide derived from SOCS7 promoted the cholinergic differentiation of ADMSCs. This novel method will contribute to research as well as regenerative medicine for cholinergic neuron diseases

Long-Term Culture of Astrocytes Attenuates the Readily Releasable Pool of Synaptic Vesicles

<div><p>The astrocyte is a major glial cell type of the brain, and plays key roles in the formation, maturation, stabilization and elimination of synapses. Thus, changes in astrocyte condition and age can influence information processing at synapses. However, whether and how aging astrocytes affect synaptic function and maturation have not yet been thoroughly investigated. Here, we show the effects of prolonged culture on the ability of astrocytes to induce synapse formation and to modify synaptic transmission, using cultured autaptic neurons. By 9 weeks in culture, astrocytes derived from the mouse cerebral cortex demonstrated increases in β-galactosidase activity and glial fibrillary acidic protein (GFAP) expression, both of which are characteristic of aging and glial activation <em>in vitro</em>. Autaptic hippocampal neurons plated on these aging astrocytes showed a smaller amount of evoked release of the excitatory neurotransmitter glutamate, and a lower frequency of miniature release of glutamate, both of which were attributable to a reduction in the pool of readily releasable synaptic vesicles. Other features of synaptogenesis and synaptic transmission were retained, for example the ability to induce structural synapses, the presynaptic release probability, the fraction of functional presynaptic nerve terminals, and the ability to recruit functional AMPA and NMDA glutamate receptors to synapses. Thus the presence of aging astrocytes affects the efficiency of synaptic transmission. Given that the pool of readily releasable vesicles is also small at immature synapses, our results are consistent with astrocytic aging leading to retarded synapse maturation.</p> </div

Astrocytes cultured for long periods exhibit detectable aging at the 9- and 16-week time points.

<p>(A) Representative bright-field images of astrocytes mass-cultured for 5, 9, and 16 weeks <i>in vitro</i>. In each case, cells were positive for β-galactosidase activity (blue), but the frequency of such cells was higher in cells cultured <i>in vitro</i> for a prolonged period. Scale bars, 100 µm. (B) Percentages of astrocytes positive for β-galactosidase activity in mass cultures 5-, 9- and 16-weeks of age. (C) Density of astrocytes based on nuclear counterstaining with DAPI, in mass cultures 5-, 9- and 16-weeks of age (<i>N</i> = 3 cultures at each age, with each culture representing 3 image fields). Data were obtained from the same culture as in (B). (D) Representative immunostaining of astrocyte microislands cultured <i>in vitro</i> for 5, 9, and 16 weeks. The cells were immunostained for the astrocyte marker GFAP (red), and counterstained with DAPI to detect nuclei (blue). Note that the area positive for GFAP immunoreactivity increased with astrocyte age. Scale bars, 100 µm. (E) The area per astrocyte that was positive for GFAP staining. This value is calculated by dividing the measured area by the number of astrocytes in each microisland. (F) The number of astrocytes in each microisland, following culture for 5, 9 and 16 weeks (<i>n</i> = 30 microislands, respectively). Data were obtained from the same culture as in (E). *, p<0.05; **, p<0.01; ***, p<0.001.</p

Astrocyte aging significantly reduces the size of the readily releasable pool of synaptic vesicles.

<p>(A) Representative traces of the responses to 0.5 M sucrose (10 s) in autaptic neurons co-cultured with 5- (control), 9- and 16-week-old astrocytes. The response to the hypertonic sucrose solution was used to define neurotransmitter release from all vesicles in the readily releasable pool (RRP). The Vh was −70 mV. (B) Number of synaptic vesicles in RRP of autaptic neurons co-cultured with 5- (control), 9- and 16-week-old astrocytes (<i>n</i> = 64, 58 and 58 neurons, respectively). (C) Vesicular release probability (P_vr) in single autaptic neurons co-cultured with 5- (control), 9- and 16-week-old astrocytes (<i>n</i> = 80, 82 and 82 neurons, respectively). (D) Paired-pulse ratio (PPR) of evoked EPSCs. The amplitudes of EPSCs evoked by two action potentials separated by 50 ms were measured. Autaptic neurons were co-cultured with astrocytes cultured for 5- (control), 9- and 16-week (<i>n</i> = 64, 58 and 58 neurons, respectively). **, p<0.01.</p

Astrocyte aging does not affect presynaptically silent synapses.

<p>(A) Representative images illustrating the functional (non-silent) synapses labeled with both 10 µM fixable FM1-43FX (green) and VGLUT 1 antibody (red), and the inactive (silent) synapses labeled with VGLUT 1 antibody only (arrows). Autaptic neurons were co-cultured with 5- (control), 9- and 16-week-old astrocytes. (B) The number of VGLUT 1-positive puncta in autaptic neurons co-cultured with 5- (control), 9- and 16-week-old astrocytes (<i>n</i> = 27, 20 and 22 neurons, respectively). (C) The number of FM1-43FX-positive puncta in autaptic neurons. Data in (C-F) were obtained from the same neurons used in (B). (D) Ratio of presynaptically silent synapses to total synapses, measured as the fraction of VGLUT 1-positive puncta that did not colocalize with FM1-43FX. (E) Area (size) of the VGLUT 1-positive puncta, measured as the number of pixels. (F) Area (size) of the FM1-43FX-positive puncta, measured as the number of pixels.</p

Astrocyte aging suppresses evoked synaptic transmission.

<p>(A) Representative traces of evoked EPSCs recorded from autaptic hippocampal neurons co-cultured with astrocytes that had been cultured for 5, 9 or 16 weeks (control, 9w and 16w) by the time of electrophysiological recording. The holding potential (Vh) was step-depolarized from −70 to 0 mV for 2 ms, and returned to −70 mV. Depolarization artifacts caused by the generated action currents have been removed for clarity. (B) Average amplitudes of the evoked EPSCs in neurons co-cultured with 5- (control), 9- and 16-week-old astrocytes (<i>n</i> = 80, 82 and 86 autaptic neurons, respectively). ***, p<0.001.</p