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.

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).

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.

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.

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.

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.

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.

Difference in 24-hour urine sodium excretion between controlled and uncontrolled patients on antihypertensive drug treatment.

The objective of this study was to evaluate the association between sodium intake and blood pressure (BP) control in hypertensive patients taking antihypertensive medications by using 24-hour urine collection and 24-hour ambulatory BP. This is a cross-sectional community-based study and conducted in 2011 and 2012. A total of 1128 participants were recruited from five cities in Korea. Among them, 740 participants who had complete 24-hour urine collection and valid 24-hour ambulatory BP data were included in this study. Participants were divided into four groups: normotensives (NT, n = 441), untreated hypertensive patients (UTHT, n = 174), controlled hypertensive patients (CHT, n = 62), and uncontrolled hypertensive patients (UCHT, n = 63). UCHT and CHT groups showed higher mean age than NT and UTHT groups. UCHT and UTHT groups showed higher 24-hour systolic BP (SBP) and diastolic BP (DBP) than NT and CHT groups. UCHT group had the highest level of 24-hour urine sodium. Multivariate analysis adjusted with age, gender, body mass index, estimated glomerular filtration rate, and use of diuretics showed higher level of 24-hour urine sodium in UCHT group than that in CHT group. Multivariate logistic regression analysis revealed independent association of the amount of 24-hour urine sodium with uncontrolled BP in hypertensive patients on antihypertensive drug treatment. Higher level of 24-hour urine sodium excretion in uncontrolled hypertensive patients suggests that excessive sodium intake could be associated with blunted BP lowering efficacy of antihypertensive medications.

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.

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).

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.

Scabies mimicking graft versus host disease in a hematopoietic cell transplant recipient.

Scabies is a highly contagious skin infestation caused by the mite, Sarcoptes scabiei var. hominis. Complex responses to scabies mites in the innate, humoral, and cellular immune systems can cause skin inflammation and pruritus. Diagnosis can be challenging because scabies resembles other common skin conditions. We report the first Korean case of scabies in a hematopoietic cell transplant (HCT) recipient, initially suspected of skin graft versus host disease (GVHD). A T-cell acute lymphocytic leukemia patient underwent a sibling-matched allogeneic HCT and developed pruritus after cell engraftment. Treatment for GVHD did not improve the symptoms. He was diagnosed with scabies 30 days after the onset of symptoms.

Makorin 1 Regulates Developmental Timing in Drosophila.

The central mechanisms coordinating growth and sexual maturation are well conserved across invertebrates and vertebrates. Although mutations in the gene encoding makorin RING finger protein 3 (mkrn3 ) are associated with central precocious puberty in humans, a causal relationship has not been elucidated. Here, we examined the role of mkrn1, a Drosophila ortholog of mammalian makorin genes, in the regulation of developmental timing. Loss of MKRN1 in mkrn1 exS prolonged the 3rd instar stage and delayed the onset of pupariation, resulting in bigger size pupae. MKRN1 was expressed in the prothoracic gland, where the steroid hormone ecdysone is produced. Furthermore, mkrn1 exS larvae exhibited reduced mRNA levels of phantom, which encodes ecdysone-synthesizing enzyme and E74, which is a downstream target of ecdysone. Collectively, these results indicate that MKRN1 fine-tunes developmental timing and sexual maturation by affecting ecdysone synthesis in Drosophila. Moreover, our study supports the notion that malfunction of makorin gene family member, mkrn3 dysregulates the timing of puberty in mammals.

Comparison of effects between calcium channel blocker and diuretics in combination with angiotensin II receptor blocker on 24-h central blood pressure and vascular hemodynamic parameters in hypertensive patients: study design for a multicenter, double-blinded, active-controlled, phase 4, randomized trial.

BACKGROUND: Hypertension is a risk factor for coronary heart disease and stroke, and is one of the leading causes of death. Although over a billion people are affected worldwide, only half of them receive adequate treatment. Current guidelines on antihypertensive treatment recommend combination therapy for patients not responding to monotherapy, but as the number of pills increase, patient compliance tends to decrease. As a result, fixed-dose combination drugs with different antihypertensive agents have been developed and widely used in recent years. CCBs have been shown to be better at reducing central blood pressure and arterial stiffness than diuretics. Recent studies have reported that central blood pressure and arterial stiffness are associated with cardiovascular outcomes. This trial aims to compare the efficacy of combination of calcium channel blocker (CCB) or thiazide diuretic with an angiotensin receptor blocker (ARB). METHODS: This is a multicenter, double-blinded, active-controlled, phase 4, randomized trial, comparing the antihypertensive effects of losartan/amlodipine and losartan/hydrochlorothiazide in patients unresponsive to treatment with losartan. The primary endpoint is changes in mean sitting systolic blood pressure (msSBP) after 4 weeks of treatment. Secondary endpoints are changes in msSBP, mean 24-h ambulatory mobile blood pressure, mean 24-h ambulatory mobile central SBP, mean 24-h ambulatory carotid-femoral pulse wave velocity, ambulatory augmentation index, and microalbuminuria/proteinuria after 20 weeks of treatment. The sample size will be 119 patients for each group in order to confer enough power to test for non-inferiority regarding the primary outcome. CONCLUSION: The investigators aim to prove that combination of a CCB with ARB shows non-inferiority in lowering blood pressure compared with a combination of thiazide diuretic and ARB. We also hope to distinguish the subset of patients that are more responsive to certain types of combination drugs. The results of this study should aid physicians in selecting appropriate combination regimens to treat hypertension in certain populations. TRIAL REGISTRATION: ClinicalTrials.gov NCT02294539. Registered 12 November 2014.

Relationship between 24-h urine sodium/potassium ratio and central aortic systolic blood pressure in hypertensive patients.

Studies evaluating the relationship between measured 24-h urine sodium (24HUNa), potassium (24HUK) and aortic blood pressure (BP) are rare, and no such study has been performed with an Asian population. We evaluated the relationship between 24HUNa, 24HUK, casual BP, 24-h ambulatory BP and aortic BP by analyzing data from 524 participants with valid 24-h urine collection, 24-h ambulatory BP and central BP measurements (mean age 48.1±9.8 years, 193 men). Hypertension was defined as a 24-h ambulatory BP ⩾130/80 mm Hg or current treatment for hypertension (n=219). The participants with hypertension and high 24HUNa (mean 210.5±52.0 mmol per day, range 151.0-432.0) showed higher 24-h systolic (P=0.037) and diastolic BP (P=0.037) and aortic systolic BP (AoSBP, P=0.038) than the participants with hypertension and low 24HUNa (mean 115.7±25.0 mmol per day, range 45.6-150.0), adjusted for confounders. The participants with hypertension and a high ratio of 24HUNa and 24HUK (24HUNa/24HUK, mean 4.03±1.00, range 2.93-7.96) had higher AoSBP than the participants with hypertension and a low 24HUNa/24HUK ratio (mean 2.13±0.54, range 0.53-2.91), adjusted for confounders (P=0.026). The participants with hypertension demonstrated a significant linear relationship between AoSBP and 24HUNa/24HUK ratio that was independent of 24HUNa, according to the multiple regression analysis (P=0.047). In hypertensive patients, 24HUNa/24HUK was positively and more strongly related to AoSBP compared with 24HUNa alone. The result indicates that high sodium and low potassium intake may increase the subsequent risk of cardiovascular disease by elevating AoSBP.

Cycles of circadian illuminance are sufficient to entrain and maintain circadian locomotor rhythms in Drosophila.

Light at night disrupts the circadian clock and causes serious health problems in the modern world. Here, we show that newly developed four-package light-emitting diodes (LEDs) can provide harmless lighting at night. To quantify the effects of light on the circadian clock, we employed the concept of circadian illuminance (CIL). CIL represents the amount of light weighted toward the wavelengths to which the circadian clock is most sensitive, whereas visual illuminance (VIL) represents the total amount of visible light. Exposure to 12 h:12 h cycles of white LED light with high and low CIL values but a constant VIL value (conditions hereafter referred to as CH/CL) can entrain behavioral and molecular circadian rhythms in flies. Moreover, flies re-entrain to phase shift in the CH/CL cycle. Core-clock proteins are required for the rhythmic behaviors seen with this LED lighting scheme. Taken together, this study provides a guide for designing healthful white LED lights for use at night, and proposes the use of the CIL value for estimating the harmful effects of any light source on organismal health.

Diversification of the molecular clockwork for tissue-specific function: insight from a novel Drosophila Clock mutant homologous to a mouse Clock allele.

The circadian clock system enables organisms to anticipate the rhythmic environmental changes and to manifest behavior and physiology at advantageous times of the day. Transcriptional/translational feedback loop (TTFL) is the basic feature of the eukaryotic circadian clock and is based on the rhythmic association of circadian transcriptional activator and repressor. In Drosophila, repression of dCLOCK/CYCLE (dCLK/CYC) mediated transcription by PERIOD (PER) is critical for inducing circadian rhythms of gene expression. Pacemaker neurons in the brain control specific circadian behaviors upon environmental timing cues such as light and temperature cycle. We show here that amino acids 657-707 of dCLK are important for the transcriptional activation and the association with PER both in vitro and in vivo. Flies expressing dCLK lacking AA657-707 in Clkout genetic background, homologous to the mouse Clock allele where exon 19 region is deleted, display pacemaker-neuron-dependent perturbation of the molecular clockwork. The molecular rhythms in light-cycle-sensitive pacemaker neurons such as ventral lateral neurons (LNvs) were significantly disrupted, but those in temperature-cycle-sensitive pacemaker neurons such as dorsal neurons (DNs) were robust. Our results suggest that the dCLK-controlled TTFL diversify in a pacemaker-neuron-dependent manner which may contribute to specific functions such as different sensitivities to entraining cues. [BMB Reports 2016; 49(11): 587-589].

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.

A Randomized, Multicenter, Double-blind, Placebo-controlled, 3 × 3 Factorial Design, Phase II Study to Evaluate the Efficacy and Safety of the Combination of Fimasartan/Amlodipine in Patients With Essential Hypertension.

PURPOSE: The objective of this study was to evaluate the efficacy and safety of a fimasartan/amlodipine combination in patients with hypertension and to determine the optimal composition for a future single-pill combination formulation. METHODS: This Phase II study was conducted by using a randomized, multicenter, double-blind, placebo-controlled, 3 × 3 factorial design. After a 2-week placebo run-in period, eligible hypertensive patients (with a sitting diastolic blood pressure [SiDBP] between 90 and 114 mm Hg) were randomized to treatment. They received single or combined administration of fimasartan at 3 doses (0, 30, and 60 mg) and amlodipine at 3 doses (0, 5, and 10 mg) for 8 weeks. The primary efficacy end point was the change in SiDBP from baseline and at week 8; secondary end points included the change in SiDBP from baseline and at week 4 and the changes in sitting systolic blood pressure from baseline and at weeks 4 and 8. Treatment-emergent adverse events (AEs) were also assessed. FINDINGS: 420 Korean patients with mild to moderate hypertension were randomly allocated to the 9 groups. Mean (SD) SiDBP changes in each group after 8 weeks were as follows: placebo, -6.0 (8.5) mm Hg; amlodipine 5 mg, -10.6 (9.2) mm Hg; amlodipine 10 mg, -15.9 (7.2) mm Hg; fimasartan 30 mg, -10.1 (9.1) mm Hg; fimasartan 60 mg, -13.0 (10.0) mm Hg; fimasartan 30 mg/amlodipine 5 mg, -16.2 (8.5) mm Hg; fimasartan 30 mg/amlodipine 10 mg, -19.5 (7.5) mm Hg; fimasartan 60 mg/amlodipine 5 mg, -16.6 (6.9) mm Hg; and fimasartan 60 mg/amlodipine 10 mg, -21.5 (8.3) mm Hg. All treatment groups produced significantly greater reductions in blood pressure compared with the placebo group. In addition, all combination treatment groups had superior reductions in blood pressure compared with the monotherapy groups. In the combination treatment groups, doubling fimasartan dose in the given dose of amlodipine did not show further BP reduction, whereas doubling amlodipine dose showed significantly further BP reduction in the given dose of fimasartan. During the study period, 75 (17.9%) of 419 patients experienced 110 AEs. Ninety-five AEs were mild, 9 were moderate, and 6 were severe in intensity. Eight patients discontinued the study due to AEs. There was no significant difference in incidence of AEs among groups (P = 0.0884). The most common AE was headache (12 patients [2.9%]), followed by dizziness (11 patients [2.6%]) and elevated blood creatine phosphokinase levels (6 patients [1.4%]). IMPLICATIONS: Fimasartan combined with amlodipine produced superior blood pressure reductions and low levels of AEs compared with either monotherapy. Therefore, a single-pill combination with fimasartan 60 mg/amlodipine 10 mg will be developed. ClinicalTrials.gov: NCT01518998.