Systematic modeling-driven experiments identify distinct molecular clockworks underlying hierarchically organized pacemaker neurons.

In metazoan organisms, circadian (∼24 h) rhythms are regulated by pacemaker neurons organized in a master-slave hierarchy. Although it is widely accepted that master pacemakers and slave oscillators generate rhythms via an identical negative feedback loop of transcription factor CLOCK (CLK) and repressor PERIOD (PER), their different roles imply heterogeneity in their molecular clockworks. Indeed, in Drosophila, defective binding between CLK and PER disrupts molecular rhythms in the master pacemakers, small ventral lateral neurons (sLNvs), but not in the slave oscillator, posterior dorsal neuron 1s (DN1ps). Here, we develop a systematic and expandable approach that unbiasedly searches the source of the heterogeneity in molecular clockworks from time-series data. In combination with in vivo experiments, we find that sLNvs exhibit higher synthesis and turnover of PER and lower CLK levels than DN1ps. Importantly, light shift analysis reveals that due to such a distinct molecular clockwork, sLNvs can obtain paradoxical characteristics as the master pacemaker, generating strong rhythms that are also flexibly adjustable to environmental changes. Our results identify the different characteristics of molecular clockworks of pacemaker neurons that underlie hierarchical multi-oscillator structure to ensure the rhythmic fitness of the organism.

Dual add-on therapy of gemigliptin and dapagliflozin in patients with type 2 diabetes inadequately controlled with metformin alone: The SOLUTION 2 study.

AIM: To evaluate the efficacy and safety of gemigliptin and dapagliflozin dual add-on therapy (GEMI + DAPA) to metformin in type 2 diabetes (T2D) patients who had inadequate glycaemic control on metformin alone, compared with a single add-on of either gemigliptin (GEMI) or dapagliflozin (DAPA) to metformin. MATERIALS AND METHODS: In this randomized, double-blind, double-dummy, active-controlled, parallel-group, phase 3 study, 469 T2D patients treated with a stable dose of metformin for 8 weeks or longer were randomized to receive GEMI + DAPA (n = 157) and either GEMI (n = 156) or DAPA (n = 156). The primary endpoint was change in HbA1c levels from baseline at week 24. RESULTS: Baseline characteristics including body mass index and T2D duration were similar among groups. At week 24, the least square mean changes in HbA1c from baseline were -1.34% with GEMI + DAPA, -0.90% with GEMI (difference between GEMI + DAPA vs. GEMI -0.44% [95% confidence interval {CI}: -0.58% to -0.31%], P < .01) and -0.78% with DAPA (difference between GEMI + DAPA vs. DAPA -0.56% [95% CI: -0.69% to -0.42%], P < .01). Both upper CIs were less than 0, demonstrating the superiority of GEMI + DAPA for lowering HbA1c. The rates of responders achieving HbA1c less than 7% and less than 6.5% were greater with GEMI + DAPA (84.9%, 56.6%) than with GEMI (55.3%, 32.2%) and DAPA (49.3%, 15.3%). The incidence rate of adverse events was similar across groups, with low incidence rates of hypoglycaemia, urinary tract infection and genital infection. CONCLUSIONS: These results suggest that the addition of GEMI + DAPA to metformin as triple combination therapy was effective, safe and well-tolerated, especially for T2D patients who experienced poor glycaemic control on metformin alone.

AMP-Activated Protein Kinase Regulates Circadian Rhythm by Affecting CLOCK in Drosophila.

The circadian clock organizes the physiology and behavior of organisms to their daily environmental rhythms. The central circadian timekeeping mechanism in eukaryotic cells is the transcriptional-translational feedback loop (TTFL). In the Drosophila TTFL, the transcription factors CLOCK (CLK) and CYCLE (CYC) play crucial roles in activating expression of core clock genes and clock-controlled genes. Many signaling pathways converge on the CLK/CYC complex and regulate its activity to fine-tune the cellular oscillator to environmental time cues. We aimed to identify factors that regulate CLK by performing tandem affinity purification combined with mass spectrometry using Drosophila S2 cells that stably express HA/FLAG-tagged CLK and V5-tagged CYC. We identified SNF4Aγ, a homolog of mammalian AMP-activated protein kinase γ (AMPKγ), as a factor that copurified with HA/FLAG-tagged CLK. The AMPK holoenzyme composed of a catalytic subunit AMPKα and two regulatory subunits, AMPKß and AMPKγ, directly phosphorylated purified CLK in vitro Locomotor behavior analysis in Drosophila revealed that knockdown of each AMPK subunit in pacemaker neurons induced arrhythmicity and long periods. Knockdown of AMPKß reduced CLK levels in pacemaker neurons, and thereby reduced pre-mRNA and protein levels of CLK downstream core clock genes, such as period and vrille Finally, overexpression of CLK reversed the long-period phenotype that resulted from AMPKß knockdown. Thus, we conclude that AMPK, a central regulator of cellular energy metabolism, regulates the Drosophila circadian clock by stabilizing CLK and activating CLK/CYC-dependent transcription.SIGNIFICANCE STATEMENT Regulation of the circadian transcription factors CLK and CYC is fundamental to synchronize the core clock with environmental changes. Here, we show that the AMPKγ subunit of AMPK, a central regulator of cellular metabolism, copurifies with the CLK/CYC complex in Drosophila S2 cells. Furthermore, the AMPK holoenzyme directly phosphorylates CLK in vitro This study demonstrates that AMPK activity regulates the core clock in Drosophila by activating CLK, which enhances circadian transcription. In mammals, AMPK affects the core clock by downregulating circadian repressor proteins. It is intriguing to note that AMPK activity is required for core clock regulation through circadian transcription enhancement, whereas the target of AMPK action is different in Drosophila and mammals (positive vs negative element, respectively).

Pacemaker-neuron-dependent disturbance of the molecular clockwork by a Drosophila CLOCK mutant homologous to the mouse Clock mutation.

Circadian clocks are composed of transcriptional/translational feedback loops (TTFLs) at the cellular level. In Drosophila TTFLs, the transcription factor dCLOCK (dCLK)/CYCLE (CYC) activates clock target gene expression, which is repressed by the physical interaction with PERIOD (PER). Here, we show that amino acids (AA) 657-707 of dCLK, a region that is homologous to the mouse Clock exon 19-encoded region, is crucial for PER binding and E-box-dependent transactivation in S2 cells. Consistently, in transgenic flies expressing dCLK with an AA657-707 deletion in the Clock (Clk(out)) genetic background (p{dClk-Δ};Clk(out)), oscillation of core clock genes' mRNAs displayed diminished amplitude compared with control flies, and the highly abundant dCLKΔ657-707 showed significantly decreased binding to PER. Behaviorally, the p{dClk-Δ};Clk(out) flies exhibited arrhythmic locomotor behavior in the photic entrainment condition but showed anticipatory activities of temperature transition and improved free-running rhythms in the temperature entrainment condition. Surprisingly, p{dClk-Δ};Clk(out) flies showed pacemaker-neuron-dependent alterations in molecular rhythms; the abundance of dCLK target clock proteins was reduced in ventral lateral neurons (LNvs) but not in dorsal neurons (DNs) in both entrainment conditions. In p{dClk-Δ};Clk(out) flies, however, strong but delayed molecular oscillations in temperature cycle-sensitive pacemaker neurons, such as DN1s and DN2s, were correlated with delayed anticipatory activities of temperature transition. Taken together, our study reveals that the LNv molecular clockwork is more sensitive than the clockwork of DNs to dysregulation of dCLK by AA657-707 deletion. Therefore, we propose that the dCLK/CYC-controlled TTFL operates differently in subsets of pacemaker neurons, which may contribute to their specific functions.

Drosophila peptidyl-prolyl isomerase Pin1 modulates circadian rhythms via regulating levels of PERIOD.

In animal circadian clock machinery, the phosphorylation program of PERIOD (PER) leads to the spatio-temporal regulation of diverse PER functions, which are crucial for the maintenance of ~24-hr circadian rhythmicity. The peptidyl-prolyl isomerase PIN1 modulates the diverse functions of its substrates by inducing conformational changes upon recognizing specific phosphorylated residues. Here, we show that overexpression of Drosophila pin1, dodo (dod), lengthens the locomotor behavioral period. Using Drosophila S2 cells, we demonstrate that Dod associates preferentially with phosphorylated species of PER, which delays the phosphorylation-dependent degradation of PER. Consistent with this, PER protein levels are higher in flies overexpressing dod. Taken together, we suggest that Dod plays a role in the maintenance of circadian period by regulating PER metabolism.

Usefulness of the parameters of quantitative myocardial perfusion contrast echocardiography in patients with chronic total occlusion and collateral flow.

BACKGROUND: Microvascular obstruction becomes more severe with longer duration of ischemia, such as chronic total occlusion (CTO) which used to have collateral flow. In this study, we explored the correlation between parameters measured using quantitative myocardial perfusion contrast echocardiography (MCE) and the angiographic collateral flow grades in patients with CTO. Furthermore, we investigated the usefulness of the parameters of quantitative MCE for the measurement of microvasculature changes after revascularization of CTO lesions. METHODS: Between January 2011 and January 2013, 44 patients who had undergone coronary angiography (CAG) due to chest pain and had confirmed CTO lesions were enrolled in this prospective observational study. All patients had baseline MCE within 24 hours after diagnostic CAG. Patients were then assigned to one of two groups: a medical therapy group (Group I, n = 20) or a reperfusion group with percutaneous coronary intervention (PCI) (Group II, n = 24). All patients had follow-up MCE 3 months later. RESULTS: Consistent with the CAG results in both groups, on baseline MCE, the myocardial blood flow (AI × ß) values were higher in Grade III collateral flow than in Grade I or II collateral flow (AI of collateral flow Grade I vs. Grade II vs. Grade III: 2.34 ± 2.65 vs. 2.52 ± 2.67 vs. 3.87 ± 4.57, P = 0.038). The plateau acoustic intensity (AI) and wall-motion score index (WMSI) were significantly improved at the 3-month follow-up after successful reperfusion with PCI (5.75 ± 3.52 before vs. 8.11 ± 6.02 after, P = 0.004) and (1.76 ± 0.83 before vs. 1.43 ± 0.64 after, P ≤ 0.001), respectively. However, the AI and WMSI values were not improved in the medical treatment group, (6.04 ± 4.64 before vs. 6.01 ± 5.52 after, P = 0.966) and (1.61 ± 0.82 before vs. 1.66 ± 0.67 after, P = 0.616), respectively. CONCLUSIONS: MCE is a useful tool for estimating microvascularity in patients with CTO lesions and correlates well with angiographic collateral flow.

Delineation of a Fat tumor suppressor pathway.

Recent studies in Drosophila melanogaster of the protocadherins Dachsous and Fat suggest that they act as ligand and receptor, respectively, for an intercellular signaling pathway that influences tissue polarity, growth and gene expression, but the basis for signaling downstream of Fat has remained unclear. Here, we characterize functional relationships among D. melanogaster tumor suppressors and identify the kinases Discs overgrown and Warts as components of a Fat signaling pathway. fat, discs overgrown and warts regulate a common set of downstream genes in multiple tissues. Genetic experiments position the action of discs overgrown upstream of the Fat pathway component dachs, whereas warts acts downstream of dachs. Warts protein coprecipitates with Dachs, and Warts protein levels are influenced by fat, dachs and discs overgrown in vivo, consistent with its placement as a downstream component of the pathway. The tumor suppressors Merlin, expanded, hippo, salvador and mob as tumor suppressor also share multiple Fat pathway phenotypes but regulate Warts activity independently. Our results functionally link what had been four disparate groups of D. melanogaster tumor suppressors, establish a basic framework for Fat signaling from receptor to transcription factor and implicate Warts as an integrator of multiple growth control signals.

Ferritin is independently associated with the presence of coronary artery calcium in 12,033 men.

OBJECTIVE: Ferritin concentrations are often increased in patients with metabolic syndrome and type 2 diabetes mellitus, but few reports have examined the associations between ferritin and atherosclerosis. We investigated whether any relationship between ferritin and coronary artery calcium score (CACS) >0 (as a marker of atherosclerosis) was independent of potential confounders, such as iron-binding capacity (transferrin), low-grade inflammation, and cardiovascular risk factors. METHODS AND RESULTS: Data were analyzed from a South Korean occupational cohort of 12 033 men who underwent a cardiac computed tomography estimation of CACS and measurements of multiple cardiovascular risk factors. One-thousand three- hundred-fifteen of 12 033 (11.2%) subjects had a CACS >0. For people with a CACS >0, median (interquartile range) ferritin concentration was 196.8 (136.3-291.9) compared with 182.2 (128.1-253.6) in people with a CACS=0; P<0.001. In the highest ferritin quartile, 14.7% (442/3008) of subjects had a CACS >0 compared with 9.7% (292/3010) in the lowest quartile (P<0.0001). With increasing ferritin quartiles, there were also higher proportions of people with diabetes mellitus (P<0.0001), hypertension (P<0.0001), coronary heart disease (P=0.003), and a Framingham Risk Score >10% (P<0.0001). In logistic regression modeling with CACS >0 as the outcome, ferritin but not transferrin was independently associated with CACS >0 (odds ratio for highest quartile versus lowest quartile, 1.66 [95% CI, 1.3-1.98]; P=0.0001). CONCLUSIONS: Increased ferritin concentrations are associated with the presence of a marker of early coronary artery atherosclerosis, independently of traditional cardiovascular risk factors including Framingham risk score, transferrin, preexisting vascular disease, diabetes mellitus, metabolic syndrome factors, and low-grade inflammation.

Starvation driven diffusion as a survival strategy of biological organisms.

The purpose of this article is to introduce a diffusion model for biological organisms that increase their motility when food or other resource is insufficient. It is shown in this paper that Fick's diffusion law does not explain such a starvation driven diffusion correctly. The diffusion model for nonuniform Brownian motion in Kim (Einstein's random walk and thermal diffusion, preprint http://amath.kaist.ac.kr/papers/Kim/31.pdf , 2013) is employed in this paper and a Fokker-Planck type diffusion law is obtained. Lotka-Volterra type competition systems with spatial heterogeneity are tested, where one species follows the starvation driven diffusion and the other follows the linear diffusion. In heterogeneous environments, the starvation driven diffusion turns out to be a better survival strategy than the linear one. Various issues such as the global asymptotic stability, convergence to an ideal free distribution, the extinction and coexistence of competing species are discussed.

A waterborne outbreak and detection of cryptosporidium oocysts in drinking water of an older high-rise apartment complex in seoul.

From May to June 2012, a waterborne outbreak of 124 cases of cryptosporidiosis occurred in the plumbing systems of an older high-rise apartment complex in Seoul, Republic of Korea. The residents of this apartment complex had symptoms of watery diarrhea and vomiting. Tap water samples in the apartment complex and its adjacent buildings were collected and tested for 57 parameters under the Korean Drinking Water Standards and for additional 11 microbiological parameters. The microbiological parameters included total colony counts, Clostridium perfringens, Enterococcus, fecal streptococcus, Salmonella, Shigella, Pseudomonas aeruginosa, Cryptosporidium oocysts, Giardia cysts, total culturable viruses, and Norovirus. While the tap water samples of the adjacent buildings complied with the Korean Drinking Water Standards for all parameters, fecal bacteria and Cryptosporidium oocysts were detected in the tap water samples of the outbreak apartment complex. It turned out that the agent of the disease was Cryptosporidium parvum. The drinking water was polluted with sewage from a septic tank in the apartment complex. To remove C. parvum oocysts, we conducted physical processes of cleaning the water storage tanks, flushing the indoor pipes, and replacing old pipes with new ones. Finally we restored the clean drinking water to the apartment complex after identification of no oocysts.

Randomized, multicenter, parallel, open, phase 4 study to compare the efficacy and safety of rosuvastatin/amlodipine polypill versus atorvastatin/amlodipine polypill in hypertension patient with dyslipidemia.

The authors performed this study to investigate the efficacy and safety of a rosuvastatin (RSV)/amlodipine (AML) polypill compared with those of atorvastatin (ATV)/AML polypill. We included 259 patients from 21 institutions in Korea. Patients were randomly assigned to 1 of 3 treatment groups: RSV 10 mg/AML 5 mg, RSV 20 mg/AML 5 mg, or ATV 20 mg /AML 5 mg. The primary endpoint was the efficacy of the RSV 10.20 mg/AML 5 mg via percentage changes in LDL-C after 8 weeks of treatment, compared with the ATV 20 mg /AML 5 mg. There was a significant difference in the mean percentage change of LDL-C at 8 weeks between the RSV 10 mg/AML 5 mg and the ATV 20 mg/AML 5 mg (full analysis set [FAS]: -7.08%, 95% CI: -11.79 to -2.38, p = .0034, per-protocol analysis set [PPS]: -6.97%, 95% CI: -11.76 to -2.19, p = .0046). Also, there was a significant difference in the mean percentage change of LDL-C at 8 weeks between the RSV 20 mg/AML 5 mg and the ATV 20 mg/AML 5 mg (FAS: -10.13%, 95% CI: -15.41 to -4.84, p = .0002, PPS: -10.96%, 95% CI: -15.98 to -5.93, p < .0001). There was no significant difference in the adverse events rates between RSV 10 mg/AML 5 mg, RSV 20 mg/AML 5 mg, and ATV 20 mg/AML 5 mg. In conclusion, while maintaining safety, RSV 10 mg/AML 5 mg and the RSV 20 mg/AML 5 mg more effectively reduced LDL-C compared with the ATV 20 mg /AML 5 mg (Clinical trial: NCT03951207).

Ataxia-linked SLC1A3 mutations alter EAAT1 chloride channel activity and glial regulation of CNS function.

Glutamate is the predominant excitatory neurotransmitter in the mammalian central nervous system (CNS). Excitatory amino acid transporters (EAATs) regulate extracellular glutamate by transporting it into cells, mostly glia, to terminate neurotransmission and to avoid neurotoxicity. EAATs are also chloride (Cl-) channels, but the physiological role of Cl- conductance through EAATs is poorly understood. Mutations of human EAAT1 (hEAAT1) have been identified in patients with episodic ataxia type 6 (EA6). One mutation showed increased Cl- channel activity and decreased glutamate transport, but the relative contributions of each function of hEAAT1 to mechanisms underlying the pathology of EA6 remain unclear. Here we investigated the effects of 5 additional EA6-related mutations on hEAAT1 function in Xenopus laevis oocytes, and on CNS function in a Drosophila melanogaster model of locomotor behavior. Our results indicate that mutations resulting in decreased hEAAT1 Cl- channel activity but with functional glutamate transport can also contribute to the pathology of EA6, highlighting the importance of Cl- homeostasis in glial cells for proper CNS function. We also identified what we believe is a novel mechanism involving an ectopic sodium (Na+) leak conductance in glial cells. Together, these results strongly support the idea that EA6 is primarily an ion channelopathy of CNS glia.

Impact of gestational hypertension on left ventricular function and geometric pattern.

BACKGROUND: The effect of gestational hypertension on left ventricular (LV) function in previously normotensive young women has not been evaluated. METHODS AND RESULTS: A total of 106 gestational hypertensive women (GHW, 32.3 ± 4.2 years) and 93 normotensive pregnant women (NPW, 30.2 ± 4.4 years) were enrolled. Transthoracic echocardiography, including 2-dimensional strain echocardiography, was done and myocardial performance (Tei index), LV mass index (LVMI), and relative wall thickness (RWT) were analyzed. GHW had significantly increased wall thickness (interventricular septum, 9.5 ± 0.9 mm vs. 8.8 ± 1.0 mm, P < 0.001; posterior wall, 9.0 ± 1.1 mm vs. 8.5 ± 1.1 mm, P = 0.007; and RWT, 0.39 ± 0.06 vs. 0.35 ± 0.05, P = 0.02), higher LVMI (95.6 ± 17.3g/m² vs. 86.1 ± 14.5g/m², P = 0.03), longer isovolumetric relaxation time (117.7 ± 18.2 ms vs. 82.3 ± 12.6 ms, P = 0.003), lower E/A ratio (1.00 ± 0.29 vs. 1.27 ± 0.33, P = 0.002), and higher Tei index (0.48 ± 0.23 vs. 0.33 ± 0.13, P = 0.003) compared to NPW. Global longitudinal LV strain, representing LV systolic function, was also significantly reduced in GHW compared with NPW (-17.6 ± 2.95% vs. -21.2 ± 2.14%, P = 0.02). A total of 62% of GHW (n = 66) had abnormal geometry, of whom, 42 (40%) had eccentric hypertrophy (EH). A total of 93% of NPW (n = 86) had normal geometry, and only 7 NPW (7%) had abnormal geometry. CONCLUSIONS: GHW had aggravated diastolic and longitudinal systolic dysfunction. GHW had increased LVMI with the abnormal geometric pattern of EH. The reversibility of these morphological and functional impairments after delivery needs to be clarified.

Dyssynchrony contributes to false-positive myocardial perfusion SPECT results in patients with stable angina.

AIM: We designed this study to evaluate the possibility that dyssynchrony might lead to false-positive myocardial perfusion single photon emission computed tomography myocardial perfusion image (MPS) results in stable angina patients. METHODS AND RESULTS: This study included 61 patients with both clinically diagnosed stable angina and quantitative MPS results who underwent coronary angiography. The patients were divided into two groups: those who had positive MPS results and normal coronary angiography (Group I, n = 28, 64.05 ± 10.14 years, 11 males and 17 females) and those who had positive MPS results and significant coronary lesions as determined by coronary angiography (Group II, n = 33, 69.2 ± 10.4 years, 14 males and 19 females). The maximal difference in time-to-peak myocardial sustained systolic velocity among all 12 left ventricular (LV) segments (maximal difference in TS) was significantly delayed in Group I as compared with Group II (125.00 ± 46.10 vs. 87.33 ± 40.53 ms, P=0.001). The standard deviation of the time-to-peak myocardial sustained systolic velocity of all 12 LV segments (TS-SD) was also significantly different in the two groups (45.12 ± 19.25 vs. 30.10 ± 15.80 , P=0.002). CONCLUSION: Dyssynchrony may be a cause of false-positive quantitative MPS results, even if patients have narrow QRS complexes on ECG. Dyssynchrony index can increase the specificity of quantitative MPS in stable angina patients.

A ten-year survey of Giardia cysts in drinking water supplies of Seoul, the Republic of Korea.

To understand the distribution of Giardia cysts in drinking water supplies in Seoul, Korea, we collected water samples quarterly at 6 intakes in the Han River, its largest stream and 6 conventional water treatment plants (WTPs) serving drinking water, from 2000 to 2009. Giardia cysts in each of 10 L water were confirmed in 35.0% of intake water samples and the arithmetic mean was 1.65 cysts/10 L (range 0-35 cysts/10 L). The lowest cyst density was observed at Paldang and Kangbuk intakes, and the pollution level was higher at 4 intakes downstream. It seemed that these 4 intakes were under influence of Wangsuk stream at the end of which cysts were found in all samples with the mean of 140 cysts/10 L. The annual mean number of cysts was 0.21-4.21 cysts/10 L, and the cyst level at the second half of the 10 years was about 1/5 of that at first half on average. The cysts were more frequently found in winter, and their mean density was 3.74 cysts/10 L in winter and 0.80-1.08 cysts/10 L in other seasons. All finished water samples collected at 6 WTPs were negative for Giardia in each of 100 L sample for 10 years and cyst removal by physical process was average 2.9-log. It was concluded that conventional water treatment at 6 WTPs of Seoul appears to remove the cysts effectively under the present level of their source water. Domestic wastewater from the urban region could be an important source of Giardia pollution in the river.

Metabolic control of daily locomotor activity mediated by tachykinin in Drosophila.

Metabolism influences locomotor behaviors, but the understanding of neural curcuit control for that is limited. Under standard light-dark cycles, Drosophila exhibits bimodal morning (M) and evening (E) locomotor activities that are controlled by clock neurons. Here, we showed that a high-nutrient diet progressively extended M activity but not E activity. Drosophila tachykinin (DTk) and Tachykinin-like receptor at 86C (TkR86C)-mediated signaling was required for the extension of M activity. DTk neurons were anatomically and functionally connected to the posterior dorsal neuron 1s (DN1ps) in the clock neuronal network. The activation of DTk neurons reduced intracellular Ca2+ levels in DN1ps suggesting an inhibitory connection. The contacts between DN1ps and DTk neurons increased gradually over time in flies fed a high-sucrose diet, consistent with the locomotor behavior. DN1ps have been implicated in integrating environmental sensory inputs (e.g., light and temperature) to control daily locomotor behavior. This study revealed that DN1ps also coordinated nutrient information through DTk signaling to shape daily locomotor behavior.

Loss of UCHL1 rescues the defects related to Parkinson's disease by suppressing glycolysis.

The role of ubiquitin carboxyl-terminal hydrolase L1 (UCHL1; also called PARK5) in the pathogenesis of Parkinson's disease (PD) has been controversial. Here, we find that the loss of UCHL1 destabilizes pyruvate kinase (PKM) and mitigates the PD-related phenotypes induced by PTEN-induced kinase 1 (PINK1) or Parkin loss-of-function mutations in Drosophila and mammalian cells. In UCHL1 knockout cells, cellular pyruvate production and ATP levels are diminished, and the activity of AMP-activated protein kinase (AMPK) is highly induced. Consequently, the activated AMPK promotes the mitophagy mediated by Unc-51-like kinase 1 (ULK1) and FUN14 domain-containing 1 (FUNDC1), which underlies the effects of UCHL1 deficiency in rescuing PD-related defects. Furthermore, we identify tripartite motif-containing 63 (TRIM63) as a previously unknown E3 ligase of PKM and demonstrate its antagonistic interaction with UCHL1 to regulate PD-related pathologies. These results suggest that UCHL1 is an integrative factor for connecting glycolysis and PD pathology.

Prevalence and characteristics of isolated nocturnal hypertension in the general population.

BACKGROUND/AIMS: Ascertaining the prevalence of isolated nocturnal hypertension (INHT) in the general population and identifying the characteristics of patients with INHT may be important to determine patients who should receive 24- hour ambulatory blood pressure (BP) measurements. This study aimed to evaluate the prevalence and characteristics of INHT in the general population. METHODS: Of 1,128 participants (aged 20 to 70 years), we analyzed 823 who had valid 24-hour ambulatory BP measurements and were not on antihypertensive drug treatment. RESULTS: The prevalence of INHT in the study was 22.8%. Individuals with INHT had a higher office, 24-hour, and daytime and nighttime ambulatory systolic and diastolic BPs compared to individuals with sustained day-night normotension. INHT was more prevalent in individuals with masked hypertension (MH) than in those with sustained hypertension (59.8% vs. 15.6%, p < 0.001). Among individuals with INHT, 92.6% had MH. Among individuals with office BP-based prehypertension, 34.5% had both INHT and MH. The prevalence of INHT was highest in individuals with office BP-based prehypertension. INHT was an independent determinant of MH after adjustment for age, sex, body mass index, diabetes, low-density-lipoprotein cholesterol, 24-hour systolic and diastolic BP, systolic and diastolic BP dipping, and systolic and diastolic BP non-dipping. CONCLUSION: The present study showed that INHT is not uncommon and is a major determinant of MH. Our findings strongly suggest the use of 24-hour ambulatory BP measurement for individuals within the prehypertension range of office BP owing to the high prevalence of INHT and MH in this population.

Makorin 1 is required for Drosophila oogenesis by regulating insulin/Tor signaling.

Reproduction is a process that is extremely sensitive to changes in nutritional status. The nutritional control of oogenesis via insulin signaling has been reported; however, the mechanism underlying its sensitivity and tissue specificity has not been elucidated. Here, we determined that Drosophila Makorin RING finger protein 1 gene (Mkrn1) functions in the metabolic regulation of oogenesis. Mkrn1 was endogenously expressed at high levels in ovaries and Mkrn1 knockout resulted in female sterility. Mkrn1-null egg chambers were previtellogenic without egg production. FLP-FRT mosaic analysis revealed that Mkrn1 is essential in germline cells, but not follicle cells, for ovarian function. As well, AKT phosphorylation via insulin signaling was greatly reduced in the germline cells, but not the follicle cells, of the mutant clones in the ovaries. Furthermore, protein-rich diet elevated Mkrn1 protein levels, without increased mRNA levels. The p-AKT and p-S6K levels, downstream targets of insulin/Tor signaling, were significantly increased by a nutrient-rich diet in wild-type ovaries whereas those were low in Mkrn1exS compared to wild-type ovaries. Taken together, our results suggest that nutrient availability upregulates the Mkrn1 protein, which acts as a positive regulator of insulin signaling to confer sensitivity and tissue specificity in the ovaries for proper oogenesis based on nutritional status.

Dose-response association of 24-hour urine sodium and sodium to potassium ratio with nighttime blood pressure at older ages.

AIMS: We investigated the dose-response association of 24-hour urine sodium and potassium with 24-hour ambulatory blood pressure. DESIGN: Cross-sectional community-based study. METHODS: Among the 1128 participants in the community-based cross-sectional survey, 740 participants (aged 20-70 years) with complete 24-hour urine collection and valid 24-hour ambulatory blood pressure monitoring were included in the study. Participants were grouped into younger (<55 years, n = 523) and older (≥55 years, n = 217). RESULTS: In the older population, nighttime blood pressure linearly increased with 24-hour urine sodium and the sodium to potassium ratio. For 24-hour urine sodium, adjusted ß was 0.171 (95% confidence interval (CI) 0.036-0.305) for nighttime systolic blood pressure and 0.144 (95% CI 0.012-0.276) for nighttime diastolic blood pressure. For the 24-hour urine sodium to potassium ratio, adjusted ß was 0.142 (95% CI 0.013-0.270) for nighttime systolic blood pressure and 0.144 (95% CI 0.018-0.270) for nighttime diastolic blood pressure. The 24-hour blood pressure linearly increased with the 24-hour urine sodium to potassium ratio and adjusted ß was 0.133 (95% CI 0.003-0.262) for 24-hour systolic blood pressure and 0.123 (95% CI 0.003-0.244) for 24-hour diastolic blood pressure. Daytime blood pressure and 24-hour systolic blood pressure showed a significant but non-linear association with 24-hour urine sodium among the older population. In the younger population, 24-hour urine sodium, potassium and the sodium to potassium ratio were not associated with ambulatory blood pressure. CONCLUSION: In the older population, 24-hour urine sodium and the sodium to potassium ratio showed a linear and positive association with nighttime blood pressure, and 24-hour urine sodium was associated with 24-hour systolic blood pressure and daytime blood pressure in a non-linear fashion.