Impact of long-term macrolide therapy on the evaluation indicator of outpatient oral antimicrobial use according to the AWaRe classification.

The WHO recently proposed a new indicator for judging the appropriateness of antimicrobial selection according to the AWaRe classification. Although macrolides are often administered for long-term macrolide therapy, the impact of this therapy on the indicator remains unclear. This study examined the impact of this therapy on the indicator for outpatient oral antimicrobial use. Using the JMDC claims database, outpatients who were prescribed an oral antimicrobial at least once between January and December 2022 (n = 2.66 million) were included in the study. The ratio of patient numbers and antimicrobial usage (AMU) were calculated based on age group (<15, 15-64, and ≥65 years) and prescription days (1-15, 16-30, 31-60, 61-90, and ≥91 days), and AMU of each drug was corrected for defined daily doses and classified according to the AWaRe. Patients with chronic airway disease for whom macrolides were prescribed for 91 days and more were defined as long-term macrolide therapy. Macrolides accounted for more than 30 % of total oral AMU in all age groups. In the elderly, 11.2 % of patients were prescribed macrolides for 91 days or more, accounting for 66.4 % of macrolide use. With regard to diseases that were associated with macrolide prescriptions, the percentage of patients prescribed for chronic airway diseases increased as the number of days of prescription increased. These results suggest that the impact of long-term macrolide therapy should be considered when assessing the appropriateness of outpatient oral AMU according to the AWaRe classification.

KCNMA1, a pore-forming α-subunit of BK channels, regulates insulin signalling in mature adipocytes.

KCNMA1 is a pore-forming α-subunit of the large conductance Ca2+ - and voltage-activated K+ channels, referred to as BK channels, which play key roles in various physiological functions. However, the role of KCNMA1 in mature adipocytes remains unclear. In this study, we reveal that kcnma1 expression is downregulated in white adipose tissue of mice fed a high-fat diet and in hypertrophied adipocytes. Furthermore, inhibition of kcnma1 expression or treatment with a BK channel blocker attenuated insulin-induced Akt phosphorylation in mature adipocytes. These results strongly indicate that KCNMA1 contributes to the regulation of insulin signalling in mature adipocytes.

Fad24, a Positive Regulator of Adipogenesis, Is Required for S Phase Re-entry of C2C12 Myoblasts Arrested in G0 Phase and Involved in p27(Kip1) Expression at the Protein Level.

Factor for adipocyte differentiation 24 (fad24) is a positive regulator of adipogenesis. We previously found that human fad24 is abundantly expressed in skeletal muscle. However, the function of fad24 in skeletal muscle remains largely unknown. Because skeletal muscle is a highly regenerative tissue, we focused on the function of fad24 in skeletal muscle regeneration. In this paper, we investigated the role of fad24 in the cell cycle re-entry of quiescent C2C12 myoblasts-mimicked satellite cells. The expression levels of fad24 and histone acetyltransferase binding to ORC1 (hbo1), a FAD24-interacting factor, were elevated at the early phase of the regeneration process in response to cardiotoxin-induced muscle injury. The knockdown of fad24 inhibited the proliferation of quiescent myoblasts, whereas fad24 knockdown did not affect differentiation. S phase entry following serum activation is abrogated by fad24 knockdown in quiescent cells. Furthermore, fad24 knockdown cells show a marked accumulation of p27(Kip1) protein. These results suggest that fad24 may have an important role in the S phase re-entry of quiescent C2C12 cells through the regulation of p27(Kip1) at the protein level.

Targeted disruption of fad24, a regulator of adipogenesis, causes pre-implantation embryonic lethality due to the growth defect at the blastocyst stage.

In previous studies, we identified a novel gene, factor for adipocyte differentiation 24 (fad24), which plays an important role during the early stages of adipogenesis in mouse 3T3-L1 cells. Moreover, overexpression of fad24 increased the number of smaller adipocytes in white adipose tissue and improved glucose metabolic activity in mice, thus indicating that fad24 functions as a regulator of adipogenesis in vivo. However, the physiological roles of fad24 in vivo are largely unknown. In this study, we attempted to generate fad24-deficient mice by gene targeting. No fad24-null mutants were recovered after embryonic day 9.5 (E9.5). Although fad24-null embryos were detected in an expected Mendelian ratio of genotypes at E3.5, none of the homozygous mutants developed into blastocysts. In vitro culture experiments revealed that fad24-null embryos develop normally to the morula stage but acquire growth defects during subsequent stages. The number of nuclei decreased in fad24-deficient morulae compared with that in wild-type ones. These results strongly suggested that fad24 is essential for pre-implantation in embryonic development, particularly for the progression to the blastocyst stage.