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Lactoferrin (LF) is a multifunctional protein abundant in breast milk that modulates the functions of neural stem cells. Recent studies have demonstrated the efficacy of bovine LF (bLF) in mitigating behavioral changes; however, the molecular mechanisms on the nervous system have not yet been elucidated. The presented study aimed to characterize the molecular mechanisms of bLF on nerve extension in PC12 cells. PC12 cells were treated with 0.01–1000 µg/mL of bLF, and cell viability was determined using the cell counting kit-8 assay after treatment for 24 h. Morphometric evaluation was performed after 24 or 72 h of treatment with 50 ng/mL nerve growth factor (NGF) or 100–500 µg/mL bLF. The molecular mechanisms were investigated using Western blotting and real-time quantitative PCR. Cell viability was significantly decreased after treatment with 600–1000 µg/mL bLF for 24 h compared with the control group. Morphometric evaluation revealed neurite outgrowth after 72 h of NGF treatment, with a significant increase in neurite outgrowth after treatment with 250 µg/mL bLF. The phosphorylated p44/42 expression ratio peaked at 5 min and persisted for up to 10 min. Quantitative real-time PCR revealed a significant decrease in MAP2 expression. Our findings suggested that bLF enhanced PC12 cell neurite outgrowth to a similar extent as NGF. These effects are thought to be mediated via the TrkA receptor and activated by the phosphorylated ERK signaling pathway. Therefore, this study demonstrates that bLF promotes neurite outgrowth via a pathway similar to that of NGF. [ABSTRACT FROM AUTHOR]

Fluctuations in estradiol levels at each stage of life in women are considered one of the causes of mental diseases through their effects on the central nervous system. During menopause, a decrease in estradiol levels has been reported to affect the serotonin nervous system and induce depression‐like and anxiety symptoms. However, the regulation of brain and behaviour during childhood and adolescence is poorly understood. Moreover, the role of oestrogen receptors α and β in the regulation of the serotonergic nervous system has been reported, but little is known about the involvement of G protein‐coupled receptor 30. Therefore, in this study, we used an ovariectomized childhood mouse model to analyse behaviour and investigate the effects on the serotonin nervous system. We showed that ovariectomy surgery at 4 weeks of age, which is the weaning period, induced a decrease in spontaneous locomotor activity during the active period and a preference for novel mice over familiar mice in the three‐chamber social test at 10 weeks of age. In addition, the administration of G‐1, a protein‐coupled receptor 30 agonist, to ovariectomized mice suppressed spontaneous locomotor activity and the preference for novel mice. Furthermore, we demonstrated that childhood ovariectomy induces increased tryptophan hydroxylase gene expression in the raphe nucleus and increased serotonin release in the amygdaloid nucleus, and administration of G‐1 ameliorated these effects. Our study suggests that G protein‐coupled receptor 30‐mediated regulation of serotonin synthesis is involved in changes in activity and social‐cognitive behaviour due to decreased estradiol levels during childhood. [ABSTRACT FROM AUTHOR]

Lactoferrin (LF), known to be present in mammalian milk, has been reported to promote the proliferation of osteoblasts and suppress bone resorption by affecting osteoclasts. However, the mechanisms underlying the effects of human sources LF on osteoblast differentiation have not yet been elucidated, and almost studies have used LF from bovine sources. The presented study aimed to characterize the molecular mechanisms of bovine lactoferrin (IF-I) and human recombinant lactoferrin (LF-II) on MC3T3-E1 pre-osteoblast cells. MC3T3-E1 cells were treated with LF, ascorbic acid, and β-glycerophosphate (β-GP). Cell proliferation was analyzed using the MTT assay. Alkaline phosphatase activation and osteopontin expression levels were evaluated via cell staining and immunocytochemistry. The differentiation markers were examined using quantitative real-time PCR. The cell viability assay showed the treatment of 100 μg/mL LF significantly increased; however, it was suppressed by the simultaneous treatment of ascorbic acid and β-GP. Alizarin red staining showed that the 100 μg/mL treatment of LF enhanced calcification. Quantitative real-time PCR showed a significant increase in osterix expression. The results suggest that treatment with both LFs enhanced MC3T3-E1 cell differentiation and promoted calcification. The mechanisms of calcification suggest that LFs are affected by an increase in osterix and osteocalcin mRNA levels. [ABSTRACT FROM AUTHOR]

Purpose: Mohs' paste, which is composed of zinc chloride and zinc oxide starch, is used for hemostasis of superficial malignancy in the clinical setting. We investigated the concentration of intramuscular zinc in mice after Mohs' paste application and evaluated its relationship with angiogenesis from the perspective of blood flow levels within 24 h., Methods: Male C57BL/6JJmsSlc mice were administered single dose of Mohs' paste at 25%, 50%, and 75% after unilateral hind limb surgery, and glycerin, a viscosity modifier, was administered to the control group (0%). Hind limb blood flow levels were measured with a laser Doppler perfusion imaging system (n = 6). The amounts of intramuscular zinc and vascular endothelial growth factor-A (VEGF-A) expression were analyzed using inductively coupled plasma mass spectrometry (ICP-MS) and western blotting, respectively (n = 5 or 3)., Results: Blood flow levels were significantly decreased in the 50% group after 8 h, and significantly decreased in the 25% and 50% groups after 24 h. Intramuscular zinc was significantly increased in the 50% and 75% groups after 8 h. Western blotting showed that VEGF-A levels were significantly increased in the 25% and 50% groups after 8 h. Based on analytical experiments and biological investigation, we predicated the pharmacological effect of Mohs' paste and found over 50% of it is critical in the blood flow and angiogenesis suppression after more than 8 h of its application., Conclusions: The results suggest that the mechanism of blood flow suppression is independent of VEGF-A levels and might suppress future angiogenesis. Our findings support that of previous studies, in which Mohs' paste was expected to induce hemostasis and suppress angiogenesis. It is an excellent ointment that facilitates hemostasis by suppressing blood flow regardless of angiogenesis, and may be apt for situations where hemostasis is required in the clinical setting., (© 2021. Springer Nature Switzerland AG.)