Junji Saruwatari

Junji Saruwatari

orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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4 March 2014 in BMJ Open
Verified
Journal Article
Open access
YTYoshiyuki Tsuda
Yoshiyuki Tsuda
JSJunji Saruwatari
Junji Saruwatari
NYNorio Yasui-Furukori
Norio Yasui-Furukori
Objective: To clarify the effects of smoking on the disposition of two commonly used antipsychotics, olanzapine and clozapine, and to create standards to adjust the doses of these drugs in clinical practice based on the smoking status. Design: A meta-analysis was conducted by searching MEDLINE, Scopus and the Cochrane Library for relevant prospective and retrospective studies. Included studies: We included the studies that investigated the effects of smoking on the concentration to dose (C/D) ratio of olanzapine or clozapine. Primary outcome measure: The weighted mean difference was calculated using a DerSimonian-Laird random effects model, along with 95% CI. Results: Seven association studies, comprising 1094 patients (652 smokers and 442 non-smokers) with schizophrenia or other psychiatric disorders, were included in the meta-analysis of olanzapine. The C/D ratio was significantly lower in smokers than in non-smokers (p<0.00001), and the mean difference was −0.75 (ng/mL)/(mg/day) (95% CI −0.89 to −0.61). Therefore, it was estimated that if 10 and 20 mg/day of olanzapine would be administered to smokers, about 7 and 14 mg/day, respectively, should be administered to non-smokers in order to obtain the equivalent olanzapine concentration. Four association studies of clozapine were included in the meta-analysis of clozapine, comprising 196 patients (120 smokers and 76 non-smokers) with schizophrenia or other psychiatric disorders. The C/D ratio was significantly lower in smokers than in non-smokers (p<0.00001), and the mean difference was −1.11 (ng/mL)/(mg/day) (95% CI −1.53 to −0.70). Therefore, it was estimated that if 200 and 400 mg/day of clozapine would be administered to smokers, about 100 and 200 mg/day, respectively, should be administered to non-smokers. Conclusions: We suggest that the doses of olanzapine and clozapine should be reduced by 30% and 50%, respectively, in non-smokers compared with smokers in order to obtain an equivalent olanzapine or clozapine concentration.

22 July 2015 in PLOS ONE
Verified
Journal Article
Open access
PDF file
KOKentaro Oniki
Kentaro Oniki
JSJunji Saruwatari
Junji Saruwatari
TITomoko Izuka
Tomoko Izuka
AKAyami Kajiwara
Ayami Kajiwara
KMKazunori Morita
Kazunori Morita
KNKazuko Nakagawa
Kazuko Nakagawa
In normal weight subjects (body mass index < 25 kg/m2), non-alcoholic fatty liver disease (NAFLD) is likely to coexist with metabolic diseases. The patatin-like phospholipase 3 (PNPLA3) polymorphism rs738409 (c.444C>G) is associated with the risk of NAFLD and/or renal dysfunction; however, the influence of the weight status on the associations remains unknown. We aimed to clarify the associations of the PNPLA3 polymorphism with the risk of NAFLD and/or renal dysfunction, while also paying careful attention to the weight status of the subjects. Cross-sectional and retrospective longitudinal studies with 5.5 ± 1.1 years of follow-up were conducted in 740 and 393 Japanese participants (61.2 ± 10.5 and 67.5 ± 6.0 years), respectively, during a health screening program. Among 591 subjects who did not have a habitual alcohol intake and/or hepatitis B or C virus infections, the PNPLA3 G/G genotype was associated with the risk for NAFLD in normal weight subjects [odds ratio (95% CI): 3.06 (1.11–8.43), P < 0.05]. Among all subjects, carriers of the PNPLA3 G/G genotype with a normal weight had a lower eGFR than those of the C/C genotype [partial regression coefficient (SE): -3.26 (1.48), P < 0.05]. These associations were replicated in the longitudinal analyses. Among the overweight subjects, none of the genotypes were significantly associated in the cross-sectional and longitudinal analyses; however, the power of the analyses was small, especially in the analyses among overweight subjects. The findings of this study suggest that carriers of the PNPLA3 G/G genotype with a normal weight status should nevertheless be carefully monitored for the presence of NAFLD and/or renal dysfunction.

1 October 2020 in Cell Reports
Verified
Journal Article
Open access
TITomoaki Inazumi
Tomoaki Inazumi
KYKiyotaka Yamada
Kiyotaka Yamada
NSNaritoshi Shirata
Naritoshi Shirata
HSHiroyasu Sato
Hiroyasu Sato
YTYoshitaka Taketomi
Yoshitaka Taketomi
YSYukihiko Sugimoto
Yukihiko Sugimoto
Lipolysis, the breakdown of triglyceride storage in white adipose tissue, supplies fatty acids to other tissues as a fuel under fasting conditions. In morbid obesity, fibrosis limits adipocyte expandability, resulting in enforced lipolysis, ectopic fat distribution, and ultimately insulin resistance. Although basal levels of lipolysis persist even after feeding, the regulatory mechanisms of basal lipolysis remain unclear. Here, we show the important role of adipocyte prostaglandin (PG) E2-EP4 receptor signaling in controlling basal lipolysis, fat distribution, and collagen deposition during feeding-fasting cycles. The PGE2-synthesis pathway in adipocytes, which is coupled with lipolysis, is activated by insulin during feeding. By regulating the lipolytic key players, the PGE2-EP4 pathway sustains basal lipolysis as a negative feedback loop of insulin action, and perturbation of this process leads to "metabolically healthy obesity." The potential role of the human EP4 receptor in lipid regulation was also suggested through genotype-phenotype association analyses.

25 February 2023 in Nature Communications
Verified
Journal Article
Open access
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NHNobuyo Higashi-Kuwata
Nobuyo Higashi-Kuwata
KTKohei Tsuji
Kohei Tsuji
HHHironori Hayashi
Hironori Hayashi
HBHaydar Bulut
Haydar Bulut
MKMaki Kiso
Maki Kiso
HMHiroaki Mitsuya
Hiroaki Mitsuya
: COVID-19 caused by SARS-CoV-2 has continually been serious threat to public health worldwide. While a few anti-SARS-CoV-2 therapeutics are currently available, their antiviral potency is not sufficient. Here, we identify two orally available 4-fluoro-benzothiazole-containing small molecules, TKB245 and TKB248, which specifically inhibit the enzymatic activity of main protease (Mpro) of SARS-CoV-2 and significantly more potently block the infectivity and replication of various SARS-CoV-2 strains than nirmatrelvir, molnupiravir, and ensitrelvir in cell-based assays employing various target cells. Both compounds also block the replication of Delta and Omicron variants in human-ACE2-knocked-in mice. Native mass spectrometric analysis reveals that both compounds bind to dimer Mpro, apparently promoting Mpro dimerization. X-ray crystallographic analysis shows that both compounds bind to Mpro’s active-site cavity, forming a covalent bond with the catalytic amino acid Cys-145 with the 4-fluorine of the benzothiazole moiety pointed to solvent. The data suggest that TKB245 and TKB248 might serve as potential therapeutics for COVID-19 and shed light upon further optimization to develop more potent and safer anti-SARS-CoV-2 therapeutics.

1 August 2002 in Clinical Pharmacology & Therapeutics
Verified
Journal Article
Closed access
PDF file
JSJunji Saruwatari
Junji Saruwatari
KNKazuko Nakagawa
Kazuko Nakagawa
JSJunichi Shindo
Junichi Shindo
TTTakahiro Tajiri
Takahiro Tajiri
MFMasaki Fujieda
Masaki Fujieda
TITakashi Ishizaki
Takashi Ishizaki

1 January 2016 in Journal of Diabetes Research
Verified
Journal Article
Open access
PDF file
AKAyami Kajiwara
Ayami Kajiwara
AKAyana Kita
Ayana Kita
JSJunji Saruwatari
Junji Saruwatari
HMHiroko Miyazaki
Hiroko Miyazaki
YKYuki Kawata
Yuki Kawata
KNKazuko Nakagawa
Kazuko Nakagawa
Aims. We aimed to investigate the sex differences in the renal function decline among patients with type 2 diabetic mellitus (T2DM), focusing on the differences in the risk factors at early stage of renal dysfunction.Methods. A clinic-based retrospective longitudinal study (follow-up duration:8.1±1.4years) was conducted to assess the sex differences in the annual estimated glomerular filtration rate (eGFR) change in 344 (247 male and 97 female) Japanese T2DM patients. The sex differences in the risk factors of annual eGFR decline were subjected to linear regression analyses.Results. The mean annual eGFR change was-3.5±2.7%/year in females and-2.0±2.2%/year in males (P<0.001). Baseline retinopathy and proteinuria were significantly associated with a larger eGFR decline, irrespective of sex, while HbA1c and LDL-cholesterol levels were significantly associated with an eGFR decline in females only. Interactive effects were observed between sex and the HbA1c, LDL-cholesterol, retinopathy, or proteinuria levels on the annual eGFR decline.Conclusions. The increased susceptibility to poor metabolic control seemed to contribute to a higher risk of renal dysfunction in females with T2DM. Our study highlights the importance of aggressive therapeutic intervention to improve metabolic profiles at early stage, especially in females.