Differential expression of myostatin and its receptor in the porcine anterior pituitary gland

Myostatin (MSTN), known as growth and differentiation factor 8 (GDF-8), is a member of the transforming growth factor β (TGF-β) superfamily that negatively regulates skeletal muscle mass. Myostatin binds with high affinity to the receptor serine threonine kinase activin receptor type IIB (ActRIIB). Activins that also belong to the TGF-β superfamily, stimulate follicle-stimulating hormone production in gonadotrophs and suppress growth hormone and adrenocorticotropic hormone production in somatotrophs and corticotrophs, respectively. The aim of the present paper was therefore to clarify the endocrine action of MSTN in adenohypophysis. The present study details the expression and cellular localization of MSTN and ActRIIB in porcine anterior pituitary gland. The mRNA of MSTN and ActRIIB was consistently expressed in RT-PCR. Immunohistochemistry of MSTN and specific hormones showed that MSTN localized in thyrotrophs and gonadotrophs, in which most of the MSTN immunoreactive cells were identified as thyrotrophs. The immunostaining of ActRIIB was restricted to corticotrophs. These results indicate that MSTN was mainly produced in thyrotrophs and its receptor, ActRIIB, was restrictively contained in corticotrophs. Interestingly, thyrotrophs immunoreactive for MSTN were frequently close to corticotrophs immunoreactive for ActRIIB. The present study suggests that MSTN from thyrotrophs may regulate corticotroph function as a paracrine mediator among the porcine anterior pituitary cells.     

Software development for estimating the concentration of radioactive cesium in the skeletal muscles of cattle from blood samples

The 2011 earthquake severely damaged the Fukushima Daiichi Nuclear Power Plant (FNPP), resulting in the release of large quantities of radioactive material into the environment. The deposition of these radionuclides in rice straw as livestock feed led to the circulation of contaminated beef in the market. Based on the safety concern of the consumers, a reliable method for estimating concentrations of radioactive cesium in muscle tissue is needed. In this study, we analyzed the concentrations of radioactive cesium in the blood and skeletal muscle of 88 cattle, and detected a linear correlation between them. We then developed software that can be used to estimate radioactive cesium concentrations in muscle tissue from blood samples. Distribution of this software to the livestock production field would allow us to easily identify high‐risk cattle, which would be beyond the safety regulation, before shipping out to the market. This software is planned to be released as freeware. This software would contribute to food safety, and aid the recovery of the livestock industry from the damage creacted by the 2011 Tohoku earthquake and tsunami.     

Correction to: Precocious maturation in male tiger pufferfish Takifugu rubripes: genetics and endocrinology

Fisheries Science - A correction to this paper has been published: https://doi.org/10.1007/s12562-021-01505-w     

Vibrational properties of wetwood of todomatsu (<Emphasis Type="Italic">Abies sachalinensis</Emphasis>) at high temperature

The object of this study was to understand precisely the drying characteristics of wetwood of todomatsu (Abies sachalinensis Mast.). For this purpose, the vibrational properties of wetwood of todomatsu at high temperature were compared with those of normal parts that had lower green moisture content than the wetwood. Specimens were cut respectively from the wetwood and normal parts, and matched in the radial direction. The specimens and the measuring systems were placed in an electric drying oven and free-free vibration tests were conducted in the oven under absolutely dry conditions. The wetwood and the normal parts were tested separately. The temperature was raised from room temperature to 200°C and then lowered to 50°C in steps of 25°C. The specific Young’s modulus decreased with an increase in temperature during the heating process while it increased with the decreasing temperature during the cooling process. There was no significant difference in the specific Young’s modulus between the wetwood and the normal part at all tested temperatures. The loss tangent took a minimum value at about 100°C in both the heating and cooling processes. There was no significant difference in the loss tangent between the wetwood and the normal part. Thus, the elastic and viscoelastic behaviors of the wetwood appear to be similar to those of the normal part in the temperature range of an actual kiln-drying process.     

Photostable wood–inorganic composites prepared by the sol-gel process with UV absorbent

To enhance the photostability of wood against ultraviolet (UV) light, a UV absorbent, 2,2,4-trihydroxy-4-[2-hydroxy-3-(3-trimethoxysilylpropoxy)propoxy]benzophenone (BP), was applied to the reaction system for preparing SiO₂ wood–inorganic composites by sol–gel reaction. The BP–SiO₂ wood–inorganic composites obtained were examined for photostability by scanning electron microscope observations, color changes, and diffuse reflectance infrared fourier transform analyses. The results clearly indicated that compared with SiO₂ composites, BP–SiO₂ composites improved the photostability of wood. In addition, BP was stable against UV light without degradation so that the BP–SiO₂ composite should provide sustainable and high photostability of treated wood.Part of this report was presented at the 51st Annual Meeting of the Japan Wood Research Society at Tokyo, April, 2001     

Lateral female strobili production in a Japanese red pine (Pinus densiflora Sieb. et Zucc.) clone by exogenous cytokinin application

Application ofN ⁶-benzylaminopurine (BAP) and gibberellin (GA₃) to a grafted Japanese red pine (Pinus densiflora Sieb. et Zucc.) clone promoted flowering. BAP (250 mg/l) was sprayed five times to the top of branches in July or September 1992. GA₃ (100 or 500 mg/l) was applied five times to the whole plants by spray treatment during the above period, or GA₃ solution of the same concentration was injected once into a small incision made in the main stem of clone trees at the beginning of July or the middle of September 1992. In May 1993, no apical female strobili were observed at the top of the new shoots in any treatment. However, lateral female and bisexual strobili were produced in the lower part of new shoots by BAP application in September, regardless of GA₃ application. BAP applied in September without GA₃ application was sufficient to produce lateral female and bisexual strobili. In such treatment, production of female and bisexual strobili was 47 and 25, and they occurred in 16 out of 68 new shoots, 11 out of 15 treated branches and 5 out of 5 treated trees. The average number of female and bisexual strobili per new shoot was 1.06. BAP treatment either in July or in September significantly decreased (p<0.05) the production of male strobili. These results indicate that BAP application induces the development of lateral female strobili in Japanese red pine when applied during the period of floral differentiation. A part of this paper was presented at the 105th annual meeting of the Japanese Forestry Society.     

Temporal water deficit and wood formation in Cryptomeria japonica

Cell behavior in the cambium and developing xylem of 3-year-old Japanese cedar (Cryptomeria japonica D. Don.) trees, during and after an 11-day suspension of irrigation, was analyzed. Leaf xylem pressure potential and tangential strain of the stem surface were monitored throughout the experiment. Anatomical features and numbers of developing tracheids and cambial cells were observed in four trees, sampled on Days 0, 4, 8 and 11 after irrigation was suspended. Daytime xylem pressure potential decreased to -1.9 MPa on Day 7 and remained the same until irrigation was resumed on Day 11. The transverse dimensions of the tracheids, which began to form secondary walls, began to decrease on Day 4. The number of cells in the cambial zone and cell expansion zone decreased abruptly on Day 8. Tangentially aligned developing tracheids with collapsed cell walls were observed in samples harvested on Days 8 and 11. Secondary wall formation was recognized in these tracheids. After the resumption of irrigation, xylem pressure potential recovered rapidly to the same value as before the suspension of irrigation. Tangential strain increased within 30 min after the resumption of irrigation, and continued to increase until the onset of light the next day. Eighteen days after the resumption of irrigation, anatomical features of cells in the cambium and cell-expansion zone were similar to those observed before suspension of irrigation.     

Cellular localization of IL-18 and IL-18 receptor in pig anterior pituitary gland

Pro-inflammatory cytokine interleukin 18 (IL-18) has been proposed to have a role in modulating immuno-endocrine functions. Our previous study showed that IL-18 and IL-18 receptor (IL-18R) colocalized in somatotrophs of the bovine anterior pituitary gland, and the possibility that IL-18 acts on somatotrophs as an autocrine factor. In the present study, we investigated the localization of IL-18 and IL-18R in the pig anterior pituitary gland. RT-PCR analysis showed the expression of IL-18 and IL-18R mRNAin the pig anterior pituitary gland. Immunohistochemistry of IL-18 and specific hormones revealed the presence of IL-18 in somatotrophs, mammotrophs, thyrotrophs and gonadotrophs. IL-18R was localized in somatotrophs and thyrotrophs. Furthermore, the somatotrophs immunoreactive for IL-18 did not contain IL-18R. Thus, IL-18R and IL-18 were not colocalized in an identical somatotroph. These findings suggest that the localization of IL-18 in pig somatotrophs is different from that in bovine somatotrophs, although IL-18 closely associates with somatotrophs in the anterior pituitary glands in both species.     

The effects of growth and disease in serum keratan sulfate concentration in dogs

The purpose of this study is to investigate keratan sulfate (KS) concentration in the serum of puppies and the effects of age, body weight, breed and diseases. Serum samples from six neonatal dogs (4 Beagles, 2 Labrador Retrievers), and from 127 adult dogs with various diseases were collected at a Teaching Animal Hospital. Canine serum KS concentration was measured by inhibition enzyme-linked immunosorbent assay (ELISA). Samples from puppies were evaluated for growth-related changes, and samples from patients were evaluated for age, body weight, breed and disease-related changes. Serum KS concentration was high in puppies from birth to 4 months of age. KS values started to decrease from 4 months to 9 months of age, and then gradually reached to the plateau. Though in the small sample, mean KS concentration in a Labrador Retriever was higher than in Beagles during the first 10 months. The values of serum KS showed body weight-related increase within retrievers among teaching hospital population and there was significant increase in body weight-related change. Cartilage metabolism is high in canine immature joint and that activity continues for 5 months, and that higher in Labrador Retrievers rather than in Beagles. There was no effect from other factors, including age, body weight, breed and disease in all patients. Serum KS concentration of Retrievers is higher than Beagles, and that value increased with gain of body weight. We suggest that Retriever have higher cartilage metabolism with growth or ageing.     

Tumor necrosis factor-alpha induces apoptosis in cultured porcine luteal cells

Some studies in mammalian species recently demonstrated that tumor necrosis factor (TNF)-alpha plays an important role for corpus luteum (CL) function by way of apoptosis during the estrous cycle. The objectives of this study were to clarify the induction of apoptosis in cultured porcine luteal cells by TNF-alpha treatment. Luteal cells prepared from porcine ovaries collected from crossbred mature gilts on Days 10-14 of the estrous cycle were isolated and examined as follows: 1) Flow cytometric analysis was carried out to determine apoptosis in cultured luteal cells. 2) Single-cell gel electrophoresis (comet assay) was performed to investigate apoptotic DNA fragmentation in luteal cells. The results of the flow cytometric analysis and comet assay demonstrated coincidentally that TNF-alpha induces DNA fragmentation in luteal cells causing apoptosis. These results revealed that TNF-alpha is an inducing factor of apoptosis in luteal cells.