Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
11
result(s) for
"Akiyoshi, Sayo"
Sort by:
Noise-driven growth rate gain in clonal cellular populations
by
Akiyoshi, Sayo
,
Wakamoto, Yuichi
,
Nozoe, Takashi
in
Biological Sciences
,
Biophysics and Computational Biology
,
Cell Division
2016
Cellular populations in both nature and the laboratory are composed of phenotypically heterogeneous individuals that compete with each other resulting in complex population dynamics. Predicting population growth characteristics based on knowledge of heterogeneous single-cell dynamics remains challenging. By observing groups of cells for hundreds of generations at single-cell resolution, we reveal that growth noise causes clonal populations of Escherichia coli to double faster than the mean doubling time of their constituent single cells across a broad set of balanced-growth conditions. We show that the population-level growth rate gain as well as age structures of populations and of cell lineages in competition are predictable. Furthermore, we theoretically reveal that the growth rate gain can be linked with the relative entropy of lineage generation time distributions. Unexpectedly, we find an empirical linear relation between the means and the variances of generation times across conditions, which provides a general constraint on maximal growth rates. Together, these results demonstrate a fundamental benefit of noise for population growth, and identify a growth law that sets a “speed limit” for proliferation.
Journal Article
ABCG2 dysfunction causes hyperuricemia due to both renal urate underexcretion and renal urate overload
2014
Gout is a common disease which results from hyperuricemia. We have reported that the dysfunction of urate exporter ABCG2 is the major cause of renal overload (ROL) hyperuricemia, but its involvement in renal underexcretion (RUE) hyperuricemia, the most prevalent subtype, is not clearly explained so far. In this study, the association analysis with 644 hyperuricemia patients and 1,623 controls in male Japanese revealed that ABCG2 dysfunction significantly increased the risk of RUE hyperuricemia as well as overall and ROL hyperuricemia, according to the severity of impairment. ABCG2 dysfunction caused renal urate underexcretion and induced hyperuricemia even if the renal urate overload was not remarkable. These results show that ABCG2 plays physiologically important roles in both renal and extra-renal urate excretion mechanisms. Our findings indicate the importance of ABCG2 as a promising therapeutic and screening target of hyperuricemia and gout.
Journal Article
Common dysfunctional variants of ABCG2 have stronger impact on hyperuricemia progression than typical environmental risk factors
2014
Gout/hyperuricemia is a common multifactorial disease having typical environmental risks. Recently, common dysfunctional variants of
ABCG2
, a urate exporter gene also known as
BCRP
, are revealed to be a major cause of gout/hyperuricemia. Here, we compared the influence of ABCG2 dysfunction on serum uric acid (SUA) levels with other typical risk factors in a cohort of 5,005 Japanese participants. ABCG2 dysfunction was observed in 53.3% of the population investigated and its population-attributable risk percent (PAR%) for hyperuricemia was 29.2%, much higher than those of the other typical environmental risks, i.e. overweight/obesity (BMI ≥ 25.0; PAR% = 18.7%), heavy drinking (>196 g/week (male) or >98 g/week (female) of pure alcohol; PAR% = 15.4%) and aging (≥60 years old; PAR% = 5.74%). SUA significantly increased as the ABCG2 function decreased (P = 5.99 × 10
−19
). A regression analysis revealed that ABCG2 dysfunction had a stronger effect than other factors; a 25% decrease in ABCG2 function was equivalent to “an increase of BMI by 1.97-point” or “552.1 g/week alcohol intake as pure ethanol” in terms of ability to increase SUA. Therefore, ABCG2 dysfunction originating from common genetic variants has a much stronger impact on the progression of hyperuricemia than other familiar risks. Our study provides a better understanding of common genetic factors for common diseases.
Journal Article
Identification of rs671, a common variant of ALDH2, as a gout susceptibility locus
by
Okada, Rieko
,
Matsuo, Hirotaka
,
Kawai, Sayo
in
631/208/205
,
692/699/317
,
Aldehyde Dehydrogenase, Mitochondrial - genetics
2016
Gout is a common disease resulting from hyperuricemia. Recently, a genome-wide association study identified an association between gout and a single nucleotide polymorphism (SNP) rs2188380, located on an intergenic region between
MYL2
and
CUX2
on chromosome 12. However, other genes around rs2188380 could possibly be gout susceptibility genes. Therefore, we performed a fine-mapping study of the
MYL2-CUX2
region. From 8,595 SNPs in the
MYL2-CUX2
region, 9 tag SNPs were selected and genotyping of 1,048 male gout patients and 1,334 male controls was performed by TaqMan method. Eight SNPs showed significant associations with gout after Bonferroni correction. rs671 (Glu504Lys) of
ALDH2
had the most significant association with gout (
P
= 1.7 × 10
−18
, odds ratio = 0.53). After adjustment for rs671, the other 8 SNPs no longer showed a significant association with gout, while the significant association of rs671 remained. rs671 has been reportedly associated with alcohol drinking behavior and it is well-known that alcohol drinking elevates serum uric acid levels. These data suggest that rs671, a common functional SNP of
ALDH2
, is a genuine gout-associated SNP in the
MYL2-CUX2
locus and that “A” allele (Lys) of rs671 plays a protective role in the development of gout.
Journal Article
Increase of serum uric acid levels associated with APOE ε2 haplotype: a clinico-genetic investigation and in vivo approach
by
Matsuo, Hirotaka
,
Kawai, Sayo
,
Ayaori, Makoto
in
Apolipoprotein E
,
Atherosclerosis
,
Cardiovascular disease
2021
Elevated serum uric acid (SUA)—hyperuricemia—is caused by overproduction of urate or by its decreased renal and/or intestinal excretion. This disease, which is increasing in prevalence worldwide, is associated with both gout and metabolic diseases. Several studies have reported relationships between apolipoprotein E (APOE) haplotypes and SUA levels in humans; however, their results remain inconsistent. This prompted us to investigate the relationship between APOE polymorphisms and SUA levels. Our subjects were 5,272 Japanese men, premenopausal women, and postmenopausal women. Multiple linear regression analyses revealed the ε2 haplotype of APOE to be independently associated with higher SUA in men (N = 1,726) and postmenopausal women (N = 1,753), but not in premenopausal women (N = 1,793). In contrast, the ε4 haplotype was little related to SUA levels in each group. Moreover, to examine the effect of Apoe deficiency on SUA levels, we conducted animal experiments using Apoe knockout mice, which mimics ε2/ε2 carriers. We found that SUA levels in Apoe knockout mice were significantly higher than those in wild-type mice, which is consistent with the SUA-raising effect of the ε2 haplotype observed in our clinico-genetic analyses. Further analyses suggested that renal rather than intestinal underexcretion of urate could be involved in Apoe deficiency-related SUA increase. In conclusion, we successfully demonstrated that the ε2 haplotype, but not the ε4 haplotype, increases SUA levels. These findings will improve our understanding of genetic factors affecting SUA levels.
Journal Article
Genome-wide meta-analysis identifies multiple novel loci associated with serum uric acid levels in Japanese individuals
by
Kawai, Sayo
,
Hirata, Makoto
,
Kawaguchi, Makoto
in
45/43
,
631/208/205/2138
,
692/699/1670/3/2765/1528
2019
Gout is a common arthritis caused by elevated serum uric acid (SUA) levels. Here we investigated loci influencing SUA in a genome-wide meta-analysis with 121,745 Japanese subjects. We identified 8948 variants at 36 genomic loci (
P
<5 × 10
–8
) including eight novel loci. Of these, missense variants of
SESN2
and
PNPLA3
were predicted to be damaging to the function of these proteins; another five loci—
TMEM18
,
TM4SF4
,
MXD3-LMAN2
,
PSORS1C1-PSORS1C2
, and
HNF4A
—are related to cell metabolism, proliferation, or oxidative stress; and the remaining locus,
LINC01578
, is unknown. We also identified 132 correlated genes whose expression levels are associated with SUA-increasing alleles. These genes are enriched for the UniProt transport term, suggesting the importance of transport-related genes in SUA regulation. Furthermore, trans-ethnic meta-analysis across our own meta-analysis and the Global Urate Genetics Consortium has revealed 15 more novel loci associated with SUA. Our findings provide insight into the pathogenesis, treatment, and prevention of hyperuricemia/gout.
Masahiro Nakatochi et al. report a genome-wide meta-analysis of serum uric acid levels in the Japanese population. They identify 36 loci, including eight previously unreported loci, suggesting key cellular processes that contribute to elevated serum uric acid levels, which can lead to gout.
Journal Article
Independent effects of ADH1B and ALDH2 common dysfunctional variants on gout risk
2017
Gout is caused by hyperuricemia, with alcohol consumption being an established risk factor. Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are crucial enzymes for alcohol metabolism. We recently performed a genome-wide association study of gout and a subsequent fine-mapping study which identified rs671 of
ALDH2
as a gout locus. However, the association between gout and common variants of
ADH1B
has hitherto remained unreported, prompting us to investigate the association between gout and common dysfunctional variants of
ADH1B
(rs1229984) and
ALDH2
(rs671). We used 1,048 clinically defined gout cases and 1,334 controls of Japanese male. The “His carrier” (His/His or His/Arg) of rs1229984 (His48Arg) of
ADH1B
significantly increased gout risk (
P
= 4.3 × 10
−4
, odds ratio = 1.76), as did the “non-Lys carrier (Glu/Glu)” of rs671 (Glu504Lys) of
ALDH2
. Furthermore, common variants of
ADH1B
and
ALDH2
are independently associated with gout. Our findings likewise suggest that genotyping these variants can be useful for the evaluation of gout risk.
Journal Article
A common missense variant of monocarboxylate transporter 9 (MCT9/SLC16A9) gene is associated with renal overload gout, but not with all gout susceptibility
2013
Gout is a common disease caused by hyperuricemia, which shows elevated serum uric acid (SUA) levels. From a viewpoint of urate handling in humans, gout patients can be divided into those with renal overload (ROL) gout with intestinal urate underexcretion, and those with renal underexcretion (RUE) gout. Recent genome-wide association studies (GWAS) revealed an association between SUA and a variant in human monocarboxylate transporter 9 (MCT9/SLC16A9) gene. Although the function of MCT9 remains unclear, urate is mostly excreted via intestine and kidney where MCT9 expression is observed. In this study, we investigated the relationship between a variant of MCT9 and gout in 545 patients and 1,115 healthy volunteers. A missense variant of MCT9 (K258T), rs2242206, significantly increased the risk of ROL gout (p = 0.012), with odds ratio (OR) of 1.28, although it revealed no significant association with all gout cases (p = 0.10), non-ROL gout cases (p = 0.83), and RUE gout cases (p = 0.34). In any case groups and the control group, minor allele frequencies of rs2242206 were >0.40. Therefore, rs2242206 is a common missense variant and is revealed to have an association with ROL gout, indicating that rs2242206 relates to decreased intestinal urate excretion rather than decreased renal urate excretion. Our study provides clues to better understand the pathophysiology of gout as well as the physiological roles of MCT9.
Journal Article
Improvement of pharmaceutical potential of all-trans retinoic acid with hydroxypropyl-β-cyclodextrin
2011
2-Hydroxypropyl-β-cyclodextrin (HP-β-CyD) includes all-trans retinoic acid (RA), covering the double-bond area of RA with substituted hydroxypropyl groups on CyD ring, as proved by the nuclear Overhauser effect (NOE) between methylene protons on the hydroxypropyl groups and the proton on RA. The formation of an inclusion complex results in hydrophilicity and stability. The effect of RA/HP-β-CyD and that of RA without HP-β-CyD on wrinkle scores and skin elasticity during skin treatment were identical, and the cutaneous stimulus was reduced comparing with RA. The results indicated that the RA/HP-β-CyD complex should help to realize new approaches in skin rejuvenation therapy.
Journal Article