Evaluation of glomerular hemodynamic changes by sodium-glucose-transporter 2 inhibition in type 2 diabetic rats using in vivo imaging.

The mechanisms responsible for glomerular hemodynamic regulation with sodium-glucose co-transporter 2 (SGLT2) inhibitors in kidney disease due to type 2 diabetes remain unclear. Therefore, we investigated changes in glomerular hemodynamic function using an animal model of type 2 diabetes, treated with an SGLT2 inhibitor alone or in combination with a renin-angiotensin-aldosterone system inhibitor using male Zucker lean (ZL) and Zucker diabetic fatty (ZDF) rats. Afferent and efferent arteriolar diameter and single-nephron glomerular filtration rate (SNGFR) were evaluated in ZDF rats measured at 0, 30, 60, 90, or 120 minutes after the administration of a SGLT2 inhibitor (luseogliflozin). Additionally, we assessed these changes under the administration of the adenosine A1 receptor (A1aR) antagonist (8-cyclopentyl-1,3-dipropylxanthine), along with coadministration of luseogliflozin and an angiotensin II receptor blocker (ARB), telmisartan. ZDF rats had significantly increased SNGFR, and afferent and efferent arteriolar diameters compared to ZL rats, indicating glomerular hyperfiltration. Administration of luseogliflozin significantly reduced afferent vasodilatation and glomerular hyperfiltration, with no impact on efferent arteriolar diameter. Urinary adenosine levels were increased significantly in the SGLT2 inhibitor group compared to the vehicle group. A1aR antagonism blocked the effect of luseogliflozin on kidney function. Co-administration of the SGLT2 inhibitor and ARB decreased the abnormal expansion of glomerular afferent arterioles, whereas the efferent arteriolar diameter was not affected. Thus, regulation of afferent arteriolar vascular tone via the A1aR pathway is associated with glomerular hyperfiltration in type 2 diabetic kidney disease.

Activation of the inflammasome drives peritoneal deterioration in a mouse model of peritoneal fibrosis.

During peritoneal dialysis (PD), the peritoneum is exposed to a bioincompatible dialysate, deteriorating the tissue and limiting the long-term effectiveness of PD. Peritoneal fibrosis is triggered by chronic inflammation induced by a variety of stimuli, including peritonitis. Exposure to PD fluid alters peritoneal macrophages phenotype. Inflammasome activation triggers chronic inflammation. First, it was determined whether inflammasome activation causes peritoneal deterioration. In the in vivo experiments, the increased expression of the inflammasome components, caspase-1 activity, and concomitant overproduction of IL-1ß and IL-18 were observed in a mouse model of peritoneal fibrosis. ASC-positive and F4/80-positive cells colocalized in the subperitoneal mesothelial cell layer. These macrophages expressed high CD44 levels indicating that the CD44-positive macrophages contribute to developing peritoneal deterioration. Furthermore, intravital imaging of the peritoneal microvasculature demonstrated that the circulating CD44-positive leukocytes may contribute to peritoneal fibrosis. Bone marrow transplantation in ASC-deficient mice suppressed inflammasome activation, thereby attenuating peritoneal fibrosis in a high glucose-based PD solution-injected mouse model. Our results suggest inflammasome activation in CD44-positive macrophages may be involved in developing peritoneal fibrosis. The inflammasome-derived pro-inflammatory cytokines might therefore serve as new biomarkers for developing encapsulating peritoneal sclerosis.

Posttraumatic Growth as a Process Beginning Before Bereavement: New Perspectives on Theory Development.

Calhoun and Tedeschi's growth model focuses on cognitive processing after bereavement but it does not show the change in life narrative from beforehand. Our qualitative study aimed to clarify bereaved family growth and revealed new perspectives on posttraumatic growth (PTG), including that the PTG process involves a pre-bereavement experience and is not limited to positive psychological changes.Based on the two new perspectives, a discussion of PTG theory reveals that bereaved families' PTG can only be accurately captured if the pre-loss experience is included; thus, Calhoun and Tedeschi's growth model, which only captures the post-loss process, is insufficient. Additionally, positive psychological changes are not the only type of growth. When considering growth, one must focus on the process, including the experience of the person realizing that it is "okay to be who they are."

Growth Experience Bereaved of a Spouse by Cancer: Relying on Merleau-Ponty's Reorganization of the Body Schemes.

The grief experienced by bereaved families can lead to positive changes, and its relevance to the emerging concept of posttraumatic growth has been explored. However, studies on survivors bereaved of a spouse by cancer are scarce; consequently, the nature of growth remains poorly understood. This study aimed to explore the growth experiences of survivors bereaved of a spouse by cancer. Based on Merleau-Ponty's theory of the body, we phenomenologically analyzed narratives/qualitative data collected through interviews of 21 survivors bereaved of a spouse by cancer. The assessment of the growth of survivors bereaved of a spouse by cancer began before the bereavement, with the questioning of habits with the living spouse because of illness and prognosis announcement and/or bereavement, reaffirming the connection with the spouse, realizing that it provides emotional support, and becoming accustomed to who they are now in the new environment.

Endothelial Dysfunction Accelerates Impairment of Mitochondrial Function in Ageing Kidneys via Inflammasome Activation.

Chronic kidney disease is a common problem in the elderly and is associated with increased mortality. We have reported on the role of nitric oxide, which is generated from endothelial nitric oxide synthase (eNOS), in the progression of aged kidneys. To elucidate the role of endothelial dysfunction and the lack of an eNOS-NO pathway in ageing kidneys, we conducted experiments using eNOS and ASC-deficient mice. C57B/6 J mice (wild type (WT)), eNOS knockout (eNOS KO), and ASC knockout (ASC KO) mice were used in the present study. Then, eNOS/ASC double-knockout (eNOS/ASC DKO) mice were generated by crossing eNOS KO and ASC KO mice. These mice were sacrificed at 17-19 months old. The Masson positive area and the KIM-1 positive area tended to increase in eNOS KO mice, compared with WT mice, but not eNOS/ASC DKO mice. The COX-positive area was significantly reduced in eNOS KO mice, compared with WT and eNOS/ASC DKO mice. To determine whether inflammasomes were activated in infiltrating macrophages, the double staining of IL-18 and F4/80 was performed. IL-18 and F4/80 were found to be co-localised in the tubulointerstitial areas. Inflammasomes play a pivotal role in inflammaging in ageing kidneys. Furthermore, inflammasome activation may accelerate cellular senescence via mitochondrial dysfunction. The importance of endothelial function as a regulatory mechanism suggests that protection of endothelial function may be a potential therapeutic target.

Combination therapy with pemafibrate (K-877) and pitavastatin improves vascular endothelial dysfunction in dahl/salt-sensitive rats fed a high-salt and high-fat diet.

BACKGROUND: Statins suppress the progression of atherosclerosis by reducing low-density lipoprotein (LDL) cholesterol levels. Pemafibrate (K-877), a novel selective peroxisome proliferator-activated receptor α modulator, is expected to reduce residual risk factors including high triglycerides (TGs) and low high-density lipoprotein (HDL) cholesterol during statin treatment. However, it is not known if statin therapy with add-on pemafibrate improves the progression of atherosclerosis. The aim of this study was to assess the effect of combination therapy with pitavastatin and pemafibrate on lipid profiles and endothelial dysfunction in hypertension and insulin resistance model rats. METHODS: Seven-week-old male Dahl salt-sensitive (DS) rats were divided into the following five treatment groups (normal diet (ND) plus vehicle, high-salt and high-fat diet (HD) plus vehicle, HD plus pitavastatin (0.3 mg/kg/day), HD plus pemafibrate (K-877) (0.5 mg/kg/day), and HD plus combination of pitavastatin and pemafibrate) and treated for 12 weeks. At 19 weeks, endothelium-dependent relaxation of the thoracic aorta in response to acetylcholine was evaluated. RESULTS: After feeding for 12 weeks, systolic blood pressure and plasma levels of total cholesterol were significantly higher in the HD-vehicle group compared with the ND-vehicle group. Combination therapy with pitavastatin and pemafibrate significantly reduced systolic blood pressure, TG levels, including total, chylomicron (CM), very LDL (VLDL), HDL-TG, and cholesterol levels, including total, CM, VLDL, and LDL-cholesterol, compared with vehicle treatment. Acetylcholine caused concentration-dependent relaxation of thoracic aorta rings that were pre-contracted with phenylephrine in all rats. Relaxation rates in the HD-vehicle group were significantly lower compared with the ND-vehicle group. Relaxation rates in the HD-combination of pitavastatin and pemafibrate group significantly increased compared with the HD-vehicle group, although neither medication alone ameliorated relaxation rates significantly. Western blotting experiments showed increased phosphorylated endothelial nitric oxide synthase protein expression in aortas from rats in the HD-pemafibrate group and the HD-combination group compared with the HD-vehicle group. However, the expression levels did not respond significantly to pitavastatin alone. CONCLUSIONS: Combination therapy with pitavastatin and pemafibrate improved lipid profiles and endothelial dysfunction in hypertension and insulin resistance model rats. Pemafibrate as an add-on strategy to statins may be useful for preventing atherosclerosis progression.

Klotho is a novel therapeutic target in peritoneal fibrosis via Wnt signaling inhibition.

BACKGROUND: Long-term exposure to bioincompatible peritoneal dialysate causes the loss of mesothelial cells and accumulation of matrix proteins, leading to an increase in the thickness of the submesothelial layer, thereby limiting the long-term effectiveness of peritoneal dialysis (PD). However, the detailed molecular mechanisms underlying the process of peritoneal fibrosis have not been clearly elucidated. Wnt/ß-catenin signaling pathway activation has been suggested to play a pivotal role in the development of organ fibrosis. Moreover, Klotho protein can regulate Wnt/ß-catenin signaling. We examined the role of Klotho protein in reducing peritoneal fibrosis by inhibiting Wnt/ß-catenin signaling. METHODS: The ß-catenin-activated transgenic (BAT) driving expression of nuclear ß-galactosidase reporter transgenic (BAT-LacZ) mice, the alpha-Klotho gene under control of human elongation factor 1 alpha promoter [Klotho transgenic (KLTG) and C57BL/6 background] and C57BL/6 mice [wild-type (WT)] were used. The mice received daily intraperitoneal (i.p.) injections of 4.25% glucose with lactate (PD solution) or saline as a control for 4 weeks. Other mice received daily i.p. injections of the same volume of saline (normal control). RESULTS: After exposure to PD, Wnt signal activation was observed on the peritoneal mesothelial cells in WT-PD mice. The peritoneal fibrosis was also accelerated in WT-PD mice. The protein expression of ß-catenin and Wnt-inducible genes were also remarkably increased in WT-PD mice. On the other hand, KLTG-PD mice attenuated activation of Wnt/ß-catenin signaling after exposure to PD and ameliorated the progression of peritoneal fibrosis. CONCLUSIONS: Overexpression of Klotho protein protects the peritoneal membrane through attenuation of the Wnt/ß-catenin signaling pathway. The availability of recombinant Klotho protein would provide a novel potential therapeutic target in peritoneal fibrosis.

Advanced maritime adaptation in the western Pacific coastal region extends back to 35,000-30,000 years before present.

Maritime adaptation was one of the essential factors that enabled modern humans to disperse all over the world. However, geographic distribution of early maritime technology during the Late Pleistocene remains unclear. At this time, the Indonesian Archipelago and eastern New Guinea stand as the sole, well-recognized area for secure Pleistocene evidence of repeated ocean crossings and advanced fishing technology. The incomplete archeological records also make it difficult to know whether modern humans could sustain their life on a resource-poor, small oceanic island for extended periods with Paleolithic technology. We here report evidence from a limestone cave site on Okinawa Island, Japan, of successive occupation that extends back to 35,000-30,000 y ago. Well-stratified strata at the Sakitari Cave site yielded a rich assemblage of seashell artifacts, including formally shaped tools, beads, and the world's oldest fishhooks. These are accompanied by seasonally exploited food residue. The persistent occupation on this relatively small, geographically isolated island, as well as the appearance of Paleolithic sites on nearby islands by 30,000 y ago, suggest wider distribution of successful maritime adaptations than previously recognized, spanning the lower to midlatitude areas in the western Pacific coastal region.

Inhibitory Effects of Tofogliflozin on Cardiac Hypertrophy in Dahl Salt-Sensitive and Salt-Resistant Rats Fed a High-Fat Diet.

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are drugs for diabetes and might prevent heart failure. In this study, we investigated the effects of tofogliflozin, an SGLT2 inhibitor, on cardiac hypertrophy and metabolism in hypertensive rats fed a high-fat diet. Dahl salt-sensitive (DS) rats, hypertensive model rats, and Dahl salt-resistant (DR) rats, non-hypertensive model rats, were fed a high-salt and high-fat diet containing tofogliflozin (0.005%) for 9 weeks to examine the effects of this drug on cardiac hypertrophy and metabolism. Tofogliflozin tended to suppress a rise of the systolic blood pressure, relative to the control, throughout the treatment period in both DR and DS rats, and significantly suppress a rise of the systolic blood pressure, relative to the control, at the 9th week in DS rats. Tofogliflozin reduced cardiac hypertrophy (heart weight/body weight) not only in DS rats but also in DR rats. Histological analysis showed that tofogliflozin significantly decreased cardiomyocyte hypertrophy and perivascular fibrosis in both DS and DR rats. Tofogliflozin significantly decreased the expression levels of genes related to cardiac hypertrophy (encoding for natriuretic peptides A and B and interleukin-6), and to cardiac fibrosis (encoding for transforming growth factor-ß1 and collagen type IV), in DS rats. Recent studies have shown that hypertrophied and failing hearts shift to oxidizing ketone bodies as a significant fuel source. We also performed metabolome analysis for ventricular myocardial tissue. Tofogliflozin reduced 3-hydroxybutyrate, a ketone body, and significantly decreased the expression levels of ß-hydroxybutyrate dehydrogenase 1 and 3-oxoacid CoA-transferase, which are related to ketone oxidization. In conclusion, tofogliflozin ameliorated cardiac hypertrophy and fibrosis along with reduction of ketone usage in myocardial tissue.

Groundwater monitoring of an open-pit limestone quarry: groundwater characteristics, evolution and their connections to rock slopes.

Groundwater flow and its geochemical evolution in mines are important not only in the study of contaminant migration but also in the effective planning of excavation. The effects of groundwater on the stability of rock slopes and other mine constructions especially in limestone quarries are crucial because calcite, the major mineral component of limestone, is moderately soluble in water. In this study, evolution of groundwater in a limestone quarry located in Chichibu city was monitored to understand the geochemical processes occurring within the rock strata of the quarry and changes in the chemistry of groundwater, which suggests zones of deformations that may affect the stability of rock slopes. There are three distinct geological formations in the quarry: limestone layer, interbedded layer of limestone and slaty greenstone, and slaty greenstone layer as basement rock. Although the hydrochemical facies of all groundwater samples were Ca-HCO3 type water, changes in the geochemical properties of groundwater from the three geological formations were observed. In particular, significant changes in the chemical properties of several groundwater samples along the interbedded layer were observed, which could be attributed to the mixing of groundwater from the limestone and slaty greenstone layers. On the rainy day, the concentrations of Ca2+ and HCO3- in the groundwater fluctuated notably, and the groundwater flowing along the interbedded layer was dominated by groundwater from the limestone layer. These suggest that groundwater along the interbedded layer may affect the stability of rock slopes.

Secreted ectodomain of sialic acid-binding Ig-like lectin-9 and monocyte chemoattractant protein-1 promote recovery after rat spinal cord injury by altering macrophage polarity.

Engrafted mesenchymal stem cells from human deciduous dental pulp (SHEDs) support recovery from neural insults via paracrine mechanisms that are poorly understood. Here we show that the conditioned serum-free medium (CM) from SHEDs, administered intrathecally into rat injured spinal cord during the acute postinjury period, caused remarkable functional recovery. The ability of SHED-CM to induce recovery was associated with an immunoregulatory activity that induced anti-inflammatory M2-like macrophages. Secretome analysis of the SHED-CM revealed a previously unrecognized set of inducers for anti-inflammatory M2-like macrophages: monocyte chemoattractant protein-1 (MCP-1) and the secreted ectodomain of sialic acid-binding Ig-like lectin-9 (ED-Siglec-9). Depleting MCP-1 and ED-Siglec-9 from the SHED-CM prominently reduced its ability to induce M2-like macrophages and to promote functional recovery after spinal cord injury (SCI). The combination of MCP-1 and ED-Siglec-9 synergistically promoted the M2-like differentiation of bone marrow-derived macrophages in vitro, and this effect was abolished by a selective antagonist for CC chemokine receptor 2 (CCR2) or by the genetic knock-out of CCR2. Furthermore, MCP-1 and ED-Siglec-9 administration into the injured spinal cord induced M2-like macrophages and led to a marked recovery of hindlimb locomotor function after SCI. The inhibition of this M2 induction through the inactivation of CCR2 function abolished the therapeutic effects of both SHED-CM and MCP-1/ED-Siglec-9. Macrophages activated by MCP-1 and ED-Siglec-9 extended neurite and suppressed apoptosis of primary cerebellar granule neurons against the neurotoxic effects of chondroitin sulfate proteoglycans. Our data suggest that the unique combination of MCP-1 and ED-Siglec-9 repairs the SCI through anti-inflammatory M2-like macrophage induction.

Intratracheal Administration of Prostacyclin Analogue-incorporated Nanoparticles Ameliorates the Development of Monocrotaline and Sugen-Hypoxia-induced Pulmonary Arterial Hypertension.

Nanoparticles (NPs) have been used as novel drug delivery systems. Drug-incorporated NPs for local delivery might optimize the efficacy and minimize the side effects of drugs. Intravenous prostacyclin improves long-term survival in patients with pulmonary arterial hypertension (PAH), but it causes serious side effects such as catheter-related infections. We investigated the efficacy and safety of intratracheal administration of a prostacyclin analogue, beraprost (BPS), incorporated NPs in Sugen-hypoxia-normoxia and monocrotaline rat models of PAH and in human PAH pulmonary arterial smooth muscle cells (PASMCs). After a single administration, BPS NPs significantly decreased right ventricular pressure, right ventricular hypertrophy, and pulmonary artery muscularization in the 2 rat models. BPS NPs significantly improved the survival rate in the monocrotaline rat model. No infiltration of inflammatory cells, hemorrhage, or fibrosis was found in the liver, kidney, spleen, and heart after the administration of BPS NPs. No liver or kidney dysfunction was found in the blood examinations. BPS and BPS NPs significantly inhibited the proliferation of human PAH PASMCs after 24 hours of treatment. BPS NPs significantly continued to inhibit the proliferation of human PAH PASMCs at 24 hours after the removal of BPS NPs. BPS NPs significantly induced apoptosis in PAH PASMCs compared to that in non-PAH PASMCs. Intratracheal administration of BPS NPs ameliorates pulmonary hypertension in PAH rat models by a sustained antiproliferative effect and a proapoptotic effect on PAH PASMCs.

The characteristics and chronology of the earliest Acheulean at Konso, Ethiopia.

The Acheulean technological tradition, characterized by a large (>10 cm) flake-based component, represents a significant technological advance over the Oldowan. Although stone tool assemblages attributed to the Acheulean have been reported from as early as circa 1.6-1.75 Ma, the characteristics of these earliest occurrences and comparisons with later assemblages have not been reported in detail. Here, we provide a newly established chronometric calibration for the Acheulean assemblages of the Konso Formation, southern Ethiopia, which span the time period ∼1.75 to <1.0 Ma. The earliest Konso Acheulean is chronologically indistinguishable from the assemblage recently published as the world's earliest with an age of ∼1.75 Ma at Kokiselei, west of Lake Turkana, Kenya. This Konso assemblage is characterized by a combination of large picks and crude bifaces/unifaces made predominantly on large flake blanks. An increase in the number of flake scars was observed within the Konso Formation handaxe assemblages through time, but this was less so with picks. The Konso evidence suggests that both picks and handaxes were essential components of the Acheulean from its initial stages and that the two probably differed in function. The temporal refinement seen, especially in the handaxe forms at Konso, implies enhanced function through time, perhaps in processing carcasses with long and stable cutting edges. The documentation of the earliest Acheulean at ∼1.75 Ma in both northern Kenya and southern Ethiopia suggests that behavioral novelties were being established in a regional scale at that time, paralleling the emergence of Homo erectus-like hominid morphology.

IRAP deficiency attenuates diet-induced obesity in mice through increased energy expenditure.

UNLABELLED: Activation of the adipose renin-angiotensin system contributes to the development of obesity and metabolic syndrome. Insulin-regulated aminopeptidase (IRAP) has been identified a key regulator of GLUT4 transporter as well as angiotensin IV (AngIV) receptor (AT4R). Although AngII-AT1R axis appears as anorexigenic and as an effector of energy expenditure, the impact of AngIV-IRAP/AT4R axis on energy metabolism remains unknown. The aim was to determine the role of IRAP in energy metabolism in mice. METHODS AND RESULTS: In adipocyte culture, plasminogen activator inhibitor type 1 (PAI-1) expression levels were diminished in IRAP knockout (IRAP(-/-)) if compared with those of wild-type (C57Bl/6J, WT) mice. Mice were fed high-fat diet (32% fat) at age of 8 weeks. At the entry, body weight, body fat content, and parameters of saccharometabolism were similar between groups. However, IRAP(-/-) mice exhibited blunted body weight gain compared to that of WT mice, despite comparable food intake and physical activity. At 20weeks of age, IRAP(-/-) mice had 25% lower body weight than WT mice. Glucose and insulin tolerance tests revealed that the glucose disposal and the hypoglycemic effect of insulin were pronounced in IRAP(-/-) mice after a high fat diet. Indirect calorimetry demonstrated that whole-body oxygen consumption rates were significantly higher in IRAP(-/-) mice by 18% with mild hyperthermia. Analysis of brown adipose tissue (BAT) in IRAP(-/-) showed increased levels of uncoupling protein-1 (UCP-1) at basal level and adaptive thermogenesis was not impaired. CONCLUSIONS: IRAP deficiency may lead to suppression of PAI-1 expression in adipocytes and upregulation of UCP-1-mediated thermogenesis in BAT and increased energy expenditure to prevent the development of obesity, and these facts suggest a therapeutic potential of IRAP/AT4R blockade in diet-induced obesity.

High-resolution record of the Matuyama-Brunhes transition constrains the age of Javanese Homo erectus in the Sangiran dome, Indonesia.

A detailed paleomagnetic study conducted in the Sangiran area, Java, has provided a reliable age constraint on hominid fossil-bearing formations. A reverse-to-normal polarity transition marks a 7-m thick section across the Upper Tuff in the Bapang Formation. The transition has three short reversal episodes and is overlain by a thick normal polarity magnetozone that was fission-track dated to the Brunhes chron. This pattern closely resembles another high-resolution Matuyama-Brunhes (MB) transition record in an Osaka Bay marine core. In the Sangiran sediments, four successive transitional polarity fields lie just below the presumed main MB boundary. Their virtual geomagnetic poles cluster in the western South Pacific, partly overlapping the transitional virtual geomagnetic poles from Hawaiian and Canary Islands' lavas, which have a mean (40)Ar/(39)Ar age of 776 ± 2 ka. Thus, the polarity transition is unambiguously the MB boundary. A revised correlation of tuff layers in the Bapang Formation reveals that the hominid last occurrence and the tektite level in the Sangiran area are nearly coincident, just below the Upper Middle Tuff, which underlies the MB transition. The stratigraphic relationship of the tektite level to the MB transition in the Sangiran area is consistent with deep-sea core data that show that the meteorite impact preceded the MB reversal by about 12 ka. The MB boundary currently defines the uppermost horizon yielding Homo erectus fossils in the Sangiran area.

Gait pattern can alter aesthetic visual impression from a third-person perspective.

Beauty is related to our lives in various ways and examining it from an interdisciplinary approach is essential. People are very concerned with their appearance. A widely accepted beauty ideal is that the thinner an individual is, the more beautiful they are. However, the effect of continuous motion on body form aesthetics is unclear. Additionally, an upright pelvic posture in the sagittal plane during walking seems to affect the aesthetic judgments of female appearance. We directly analyzed the influence of body form and walking pattern on aesthetic visual impressions from a third-person perspective with a two-way analysis of variance. Captured motion data for three conditions-upright pelvis, normal pelvis, and posteriorly tilted pelvic posture-were applied to each of three mannequins, representing thin, standard, and obese body forms. When participants watched stimulus videos of the mannequins walking with various postures, a significantly higher score for aesthetic visual impression was noted for an upright pelvic posture than for a posteriorly tilted pelvic posture, irrespective of body form (F(2, 119) = 79.89, p < 0.001, η2 = 0.54). These findings show that the third-person perspective of beauty can be improved even without being thin by walking with an upright pelvic posture.

Evidence for Hypoxia-Induced Shift in ATP Production from Glycolysis to Mitochondrial Respiration in Pulmonary Artery Smooth Muscle Cells in Pulmonary Arterial Hypertension.

BACKGROUND: The metabolic state of pulmonary artery smooth muscle cells (PASMCs) from patients with pulmonary arterial hypertension (PAH) is not well understood. In this study, we examined the balance between glycolysis and mitochondrial respiration in non-PAH-PASMCs and PAH-PASMCs under normoxia and hypoxia. METHODS: We investigated the enzymes involved in glycolysis and mitochondrial respiration, and studied the two major energy-yielding pathways (glycolysis and mitochondrial respiration) by measuring extracellular acidification rate (ECAR) and cellular oxygen consumption rate (OCR) using the Seahorse extracellular flux technology. RESULTS: Under both normoxia and hypoxia, the mRNA and protein levels of pyruvate dehydrogenase kinase 1 and pyruvate dehydrogenase were increased in PAH-PASMCs compared with non-PAH-PASMCs. The mRNA and protein levels of lactate dehydrogenase, as well as the intracellular lactate concentration, were also increased in PAH-PASMCs compared with non-PAH-PASMCs under normoxia. However, these were not significantly increased in PAH-PASMCs compared with non-PAH-PASMCs under hypoxia. Under normoxia, ATP production was significantly lower in PAH-PASMCs (59 ± 5 pmol/min) than in non-PAH-PASMCs (70 ± 10 pmol/min). On the other hand, ATP production was significantly higher in PAH-PASMCs (31 ± 5 pmol/min) than in non-PAH-PASMCs (14 ± 3 pmol/min) under hypoxia. CONCLUSIONS: There is an underlying change in the metabolic strategy to generate ATP production under the challenge of hypoxia.

Pemafibrate Prevents Rupture of Angiotensin II-Induced Abdominal Aortic Aneurysms.

Background: Abdominal aortic aneurysm (AAA) is a life-threatening disease that lacks effective preventive therapies. This study aimed to evaluate the effect of pemafibrate, a selective peroxisome proliferator-activated receptor alpha (PPARα) agonist, on AAA formation and rupture. Methods: Experimental AAA was induced by subcutaneous angiotensin II (AngII) infusion in ApoE - / - mice for 4 weeks. Pemafibrate (0.1 mg/kg/day) was administered orally. Dihydroethidium staining was used to evaluate the reactive oxygen species (ROS). Results: The size of the AngII-induced AAA did not differ between pemafibrate- and vehicle-treated groups. However, a decreased mortality rate due to AAA rupture was observed in pemafibrate-treated mice. Pemafibrate ameliorated AngII-induced ROS and reduced the mRNA expression of interleukin-6 and tumor necrosis factor-α in the aortic wall. Gelatin zymography analysis demonstrated significant inhibition of matrix metalloproteinase-2 activity by pemafibrate. AngII-induced ROS production in human vascular smooth muscle cells was inhibited by pre-treatment with pemafibrate and was accompanied by an increase in catalase activity. Small interfering RNA-mediated knockdown of catalase or PPARα significantly attenuated the anti-oxidative effect of pemafibrate. Conclusion: Pemafibrate prevented AAA rupture in a murine model, concomitant with reduced ROS, inflammation, and extracellular matrix degradation in the aortic wall. The protective effect against AAA rupture was partly mediated by the anti-oxidative effect of catalase induced by pemafibrate in the smooth muscle cells.

Impact of shear wave dispersion slope analysis for assessing the severity of myocarditis.

This study aimed to elucidate the utility of a novel ultrasound-based technique, shear wave dispersion slope (SWDS) analysis, which estimates tissue viscosity, for evaluating the severity of myocardial inflammation. Experimental autoimmune myocarditis (EAM) at different disease phases [3-week (acute phase): n = 10, 5-week (subacute phase): n = 9, and 7-week (late phase): n = 11] were developed in male Lewis rats. SWDS was measured in the right and the left ventricular free walls (RVFW and LVFW) under a retrograde perfusion condition. Histological myocardial inflammation was evaluated by CD68 staining. The accumulation of CD68-positive cells was severe in the myocardium of the EAM 3-week group. The median (interquartile range) SWDS of RVFW was significantly higher in the EAM 3-week group [9.9 (6.5-11.0) m/s/kHz] than in the control group [5.4 (4.5-6.8) m/s/kHz] (P = 0.034). The median SWDS of LVFW was also significantly higher in the EAM 3-week group [8.1 (6.4-11.0) m/s/kHz] than in the control group [4.4 (4.2-4.8) m/s/kHz] (P = 0.003). SWDS and the percentage of CD68-positive area showed a significant correlation in RVFW (R2 = 0.64, P < 0.001) and LVFW (R2 = 0.73, P < 0.001). This study showed that SWDS was elevated in ventricular walls with acute inflammation and also significantly correlated with the degree of myocardial inflammation. These results suggest the potential of SWDS in estimating the histological severity of acute myocarditis.