Nihon Yoton Gakkaishi
Online ISSN : 1881-655X
Print ISSN : 0913-882X
ISSN-L : 0913-882X
Current issue
Showing 1-2 articles out of 2 articles from the selected issue
    2021 Volume 58 Issue 2 Pages 53-64
    Published: June 21, 2021
    Released: October 16, 2021

    The aim of this study was to examine the role of collagens in the differentiation of porcine subcutaneous preadipocytes (PSPA) using a specific post-transcriptional inhibitor of collagen synthesis, ethyl-3,4-dihydroxybenzoate (EDHB). Exponentially growing fibroblast-like PSPA cells were found to produce types I, III, IV, V and VI collagens by indirect immunofluorescence staining. When confluent preadipocyte cultures were stimulated with differentiation medium, various types of collagen matrices were assembled in the extracellular space of adipocytes. Since preadipocytes scarcely interconnect collagens despite the steady-state level expression of procollagen mRNAs, it appears that increasing the cell-associated form of collagens is an event unique to adipocytes. PSPA cells exposed to 40μM EDHB severely damaged the development of collagen fibrillar networks in adipocytes without affecting their transcription levels, and their triglyceride (TG) accumulation levels were reduced to 30% those of normally differentiated adipocytes. RT-PCR analysis also demonstrated a decrease in the expressions of some adipogenic genes including the master regulator of adipocyte gene transcription, PPARγ2, by EDHB-treated adipocytes, indicating the requirement for collagen during adipose conversion. The exogenous collagen types I, III, IV, V and VI were then individually supplied under EDHB conditions to determine whether or not they could make up for the lack of their own endogenous products. Of the five types of collagen, cells cultured on type V collagen were the only ones to improve the inhibitory effect of EDHB so as to recover up to 63.8% of TG content accompanied by the up-regulated expressions of PPARγ2 and adiponectin. These findings suggest that the extracellular signal from type V collagen is one of the major contributing factors in the differentiation pathway of porcine adipocytes.

    Download PDF (1002K)
  • Yasuo TANAKA
    2021 Volume 58 Issue 2 Pages 65-79
    Published: June 21, 2021
    Released: October 16, 2021

    In Japan, sum total value of NO2-N concentration, NO3-N concentration, and 0.4 times of NH4+-N concentration in effluent of wastewater treatment plant is regulated by Water Pollution Control Low. Though complying the standard value is important task of swine farms, control of the concentration is generally difficult for farmers. This study attempted to obtain prediction models of “NH4+-N×0.4+NO2-N+NO3-N” fluctuation by machine learning method in two swine wastewater treatment plants. Decision tree model which is one of the methods of machine learning were employed to describe a correlation between operational conditions (aeration tank water temperature, pH, and MLSS as inputs) and the concentration as an output, using data collected over about 3 years. Plant operation guidelines were provided by the decision tree models.

    Download PDF (2325K)