Diesel exhaust particle exposure exacerbates ciliary and epithelial barrier dysfunction in the multiciliated bronchial epithelium models.

Airway epithelium, the first defense barrier of the respiratory system, facilitates mucociliary clearance against inflammatory stimuli, such as pathogens and particulates inhaled into the airway and lung. Inhaled particulate matter 2.5 (PM2.5) can penetrate the alveolar region of the lung, and it can develop and exacerbate respiratory diseases. Although the pathophysiological effects of PM2.5 in the respiratory system are well known, its impact on mucociliary clearance of airway epithelium has yet to be clearly defined. In this study, we used two different 3D in vitro airway models, namely the EpiAirway-full-thickness (FT) model and a normal human bronchial epithelial cell (NHBE)-based air-liquid interface (ALI) system, to investigate the effect of diesel exhaust particles (DEPs) belonging to PM2.5 on mucociliary clearance. RNA-sequencing (RNA-Seq) analyses of EpiAirway-FT exposed to DEPs indicated that DEP-induced differentially expressed genes (DEGs) are related to ciliary and microtubule function and inflammatory-related pathways. The exposure to DEPs significantly decreased the number of ciliated cells and shortened ciliary length. It reduced the expression of cilium-related genes such as acetylated α-tubulin, ARL13B, DNAH5, and DNAL1 in the NHBEs cultured in the ALI system. Furthermore, DEPs significantly increased the expression of MUC5AC, whereas they decreased the expression of epithelial junction proteins, namely, ZO1, Occludin, and E-cadherin. Impairment of mucociliary clearance by DEPs significantly improved the release of epithelial-derived inflammatory and fibrotic mediators such as IL-1ß, IL-6, IL-8, GM-CSF, MMP-1, VEGF, and S100A9. Taken together, it can be speculated that DEPs can cause ciliary dysfunction, hyperplasia of goblet cells, and the disruption of the epithelial barrier, resulting in the hyperproduction of lung injury mediators. Our data strongly suggest that PM2.5 exposure is directly associated with ciliary and epithelial barrier dysfunction and may exacerbate lung injury.

3D-Printed Auxetic Skin Scaffold for Decreasing Burn Wound Contractures at Joints.

For patients with severe burns that consist of contractures induced by fibrous scar tissue formation, a graft must adhere completely to the wound bed to enable wound healing and neovascularization. However, currently available grafts are insufficient for scar suppression owing to their nonuniform pressure distribution in the wound area. Therefore, considering the characteristics of human skin, which is omnidirectionally stretched via uniaxial stretching, we proposed an auxetic skin scaffold with a negative Poisson's ratio (NPR) for tight adherence to the skin scaffold on the wound bed site. Briefly, a skin scaffold with the NPR effect was fabricated by creating a fine pattern through 3D printing. Electrospun layers were also added to improve adhesion to the wound bed. Fabricated skin scaffolds displayed NPR characteristics (-0.5 to -0.1) based on pulling simulation and experiment. Finger bending motion tests verified the decreased marginal forces (<50%) and deformation (<60%) of the NPR scaffold. In addition, the filling of human dermal fibroblasts in most areas (>95%) of the scaffold comprising rarely dead cells and their spindle-shaped morphologies revealed the high cytocompatibility of the developed scaffold. Overall, the developed skin scaffold may help reduce wound strictures in the joints of patients with burns as it exerts less pressure on the wound margin.

High-Intensity Focused Ultrasound Increases Collagen and Elastin Fiber Synthesis by Modulating Caveolin-1 in Aging Skin.

Caveolin-1 (Cav-1) induces cellular senescence by reducing extracellular signal-regulated kinase (ERK)1/2 phosphorylation and activating p53 via inhibition of mouse double minute 2 homolog (MDM2) and sirtuin 1 (Sirt1), promoting cell cycle arrest and decreasing fibroblast proliferation and collagen synthesis. High-intensity focused ultrasound (HIFU) treatment increases collagen synthesis, rejuvenating skin. Using H2O2-induced senescent fibroblasts and the skin of 12-month-old mice, we tested the hypothesis that HIFU increases collagen production through Cav-1 modulation. HIFU was administered at 0.3, 0.5, or 0.7 J in the LINEAR and DOT modes. In both models, HIFU administration decreased Cav-1 levels, increased ERK1/2 phosphorylation, and decreased the binding of Cav-1 with both MDM2 and Sirt1. HIFU administration decreased p53 activation (acetylated p53) and p21 levels and increased cyclin D1, cyclin-dependent kinase 2, and proliferating cell nuclear antigen levels in both models. HIFU treatment increased collagen and elastin expression, collagen fiber accumulation, and elastin fiber density in aging skin, with 0.5 J in LINEAR mode resulting in the most prominent effects. HIFU treatment increased collagen synthesis to levels similar to those in Cav-1-silenced senescent fibroblasts. Our results suggest that HIFU administration increases dermal collagen and elastin fibers in aging skin via Cav-1 modulation and reduced p53 activity.

Nutritional indices for screening sarcopenia before adult cardiac surgery.

Background: Malnutrition can increase and exacerbate sarcopenia, and preoperative nutritional indices could have potential use as screening tools for sarcopenia in all patients, not only those with limited activity. Muscle strengths, such as grip strength, chair stand test, are used to screen for sarcopenia, but these measurements are time-consuming and cannot be applied to all patients. This retrospective study was conducted to determine whether nutritional indices can predict the presence of sarcopenia before adult cardiac surgery. Methods: The study subjects were 499 patients aged ≥18 who had undergone cardiac surgery using a cardiopulmonary bypass (CPB). Bilateral psoas muscle mass areas at the top level of the iliac crest were measured by abdominal computed tomography. Preoperative nutritional statuses were evaluated using COntrolling NUTritional status (CONUT) score, Prognostic Nutritional Index (PNI), and Nutritional Risk Index (NRI). Receiver operating characteristic (ROC) curve analysis was used to identify the nutritional index that best predicted the presence of sarcopenia. Results: The 124 patients (24.8%) in the sarcopenic group were older (69.0 vs. 62.0 years; P<0.001), and had a lower mean body weight (58.90 vs. 65.70 kg; P<0.001) and body mass index (BMI) (2.22 vs. 2.49 kg/m2; P<0.001), and a poorer nutritional status than the 375 patients in the non-sarcopenic group. ROC curve analysis showed that NRI [area under the curve (AUC) 0.716, confidence intervals (CI): 0.664-0.768] better predicted the presence of sarcopenia than CONUT score (AUC 0.607, CI: 0.549-0.665) or PNI (AUC 0.574, CI: 0.515-0.633). The optimal NRI cut-off value was 105.25, which provided a sensitivity of 67.7% and a specificity of 65.1% for the prevalence of sarcopenia. The median durations of mechanical support (17 vs. 16 hours; P=0.008) and intensive care unit stay (3 vs. 2 days; P=0.001) were significantly longer in the sarcopenic group. Conclusions: NRI offers a more straightforward, faster, and reproducible screening tool than muscle strength or mass measurement for identifying sarcopenia, and an alternative means of assessment in patients with limited activity before adult cardiac surgery.

Rice Germ Attenuates Chronic Unpredictable Mild Stress-Induced Muscle Atrophy.

Chronic stress leads to hypothalamic-pituitary-adrenal axis dysfunction, increasing cortisol levels. Glucocorticoids (GCs) promote muscle degradation and inhibit muscle synthesis, eventually causing muscle atrophy. In this study, we aimed to evaluate whether rice germ supplemented with 30% γ-aminobutyric acid (RG) attenuates muscle atrophy in an animal model of chronic unpredictable mild stress (CUMS). We observed that CUMS raised the adrenal gland weight and serum adrenocorticotropic hormone (ACTH) and cortisol levels, and these effects were reversed by RG. CUMS also enhanced the expression of the GC receptor (GR) and GC-GR binding in the gastrocnemius muscle, which were attenuated by RG. The expression levels of muscle degradation-related signaling pathways, such as the Klf15, Redd-1, FoxO3a, Atrogin-1, and MuRF1 pathways, were enhanced by CUMS and attenuated by RG. Muscle synthesis-related signaling pathways, such as the IGF-1/AKT/mTOR/s6k/4E-BP1 pathway, were reduced by CUMS and enhanced by RG. Moreover, CUMS raised oxidative stress by enhancing the levels of iNOS and acetylated p53, which are involved in cell cycle arrest, whereas RG attenuated both iNOS and acetylated p53 levels. Cell proliferation in the gastrocnemius muscle was reduced by CUMS and enhanced by RG. The muscle weight, muscle fiber cross-sectional area, and grip strength were reduced by CUMS and enhanced by RG. Therefore, RG attenuated ACTH levels and cortisol-related muscle atrophy in CUMS animals.

Exogenous 8-Hydroxydeoxyguanosine Attenuates PM2.5-Induced Inflammation in Human Bronchial Epithelial Cells by Decreasing NLRP3 Inflammasome Activation.

Particulate matter 2.5 (PM2.5) induces lung injury by increasing the generation of reactive oxygen species (ROS) and inflammation. ROS aggravates NLRP3 inflammasome activation, which activates caspase-1, IL-1ß, and IL-18 and induces pyroptosis; these factors propagate inflammation. In contrast, treatment with exogenous 8-hydroxydeoxyguanosine (8-OHdG) decreases RAC1 activity and eventually decreases dinucleotide phosphate oxidase (NOX) and ROS generation. To establish modalities that would mitigate PM2.5-induced lung injury, we evaluated whether 8-OHdG decreased PM2.5-induced ROS generation and NLRP3 inflammasome activation in BEAS-2B cells. CCK-8 and lactate dehydrogenase assays were used to determine the treatment concentration. Fluorescence intensity, Western blotting, enzyme-linked immunosorbent assay, and immunoblotting assays were also performed. Treatment with 80 µg/mL PM2.5 increased ROS generation, RAC1 activity, NOX1 expression, NLRP3 inflammasome (NLRP3, ASC, and caspase-1) activity, and IL-1ß and IL-18 levels in cells; treatment with 10 µg/mL 8-OHdG significantly attenuated these effects. Furthermore, similar results, such as reduced expression of NOX1, NLRP3, ASC, and caspase-1, were observed in PM2.5-treated BEAS-2B cells when treated with an RAC1 inhibitor. These results show that 8-OHdG mitigates ROS generation and NLRP3 inflammation by inhibiting RAC1 activity and NOX1 expression in respiratory cells exposed to PM2.5.

Poly-D,L-Lactic Acid Filler Increases Extracellular Matrix by Modulating Macrophages and Adipose-Derived Stem Cells in Aged Animal Skin.

Poly-D,L-lactic acid (PDLLA) filler corrects soft tissue volume loss by increasing collagen synthesis in the dermis; however, the mechanism is not fully understood. Adipose-derived stem cells (ASCs) are known to attenuate the decrease in fibroblast collagen synthesis that occurs during aging, and nuclear factor (erythroid-derived 2)-like-2 factor (NRF2) increases ASCs survival by inducing M2 macrophage polarization and IL-10 expression. We evaluated the ability of PDLLA to induce collagen synthesis in fibroblasts by modulating macrophages and ASCs in a H2O2-induced cellular senescence model and aged animal skin. PDLLA increased M2 polarization and NRF2 and IL-10 expression in senescence-induced macrophages. Conditioned media from senescent macrophages treated with PDLLA (PDLLA-CMMΦ) reduced senescence and increased proliferation and expression of transforming growth factor-ß (TGF-ß) and fibroblast growth factor (FGF) 2 in senescence-induced ASCs. Conditioned media from senescent ASCs treated with PDLLA-CMMΦ (PDLLA-CMASCs) increased the expression of collagen 1a1 and collagen 3a1 and reduced the expression of NF-κB and MMP2/3/9 in senescence-induced fibroblasts. Injection of PDLLA in aged animal skin resulted in increased expression of NRF2, IL-10, collagen 1a1, and collagen 3a1 and increased ASCs proliferation in aged animal skin. These results suggest that PDLLA increases collagen synthesis by modulating macrophages to increase NRF2 expression, which stimulates ASCs proliferation and secretion of TGF-ß and FGF2. This leads to increased collagen synthesis, which can attenuate aging-induced soft tissue volume loss.

Poly-L-Lactic Acid Fillers Improved Dermal Collagen Synthesis by Modulating M2 Macrophage Polarization in Aged Animal Skin.

Poly-L-lactic acid (PLLA) fillers correct cutaneous volume loss by stimulating fibroblasts to synthesize collagen and by augmenting the volume. PLLA triggers the macrophage-induced activation of fibroblasts that secrete transforming growth factor-ß (TGF-ß). However, whether M2 macrophage polarization is involved in PLLA-induced collagen synthesis via fibroblast activation in aged skin is not known. Therefore, we evaluated the effect of PLLA on dermal collagen synthesis via M2 polarization in an H2O2-induced cellular senescence model and aged animal skin. H2O2-treated macrophages had increased expression levels of the M1 marker CD80 and decreased expression levels of the M2 marker CD163, which were reversed by PLLA. The expression levels of interleukin (IL)-4 and IL-13, which mediate M2 polarization, were decreased in H2O2-treated macrophages and increased upon the PLLA treatment. CD163, IL-4, and IL-13 expression levels were decreased in aged skin, but increased after the PLLA treatment. The expression levels of TGF-ß, pSMAD2/SMAD2, connective tissue growth factor (CTGF), alpha-smooth muscle actin (α-SMA), collagen type 1A1 (COL1A1), and COL3A1 were also decreased in aged skin, but increased after the PLLA treatment. Moreover, PLLA upregulated phosphatidylinositol 3-kinase p85α (PI3-kinase p85α)/protein kinase B (AKT) signaling, leading to fibroblast proliferation. PLLA decreased the expression of matrix metalloproteinase (MMP) 2 and MMP3, which destroy collagen and elastin fibers in aged skin. The amount of collagen and elastin fibers in aged skin increased following the PLLA treatment. In conclusion, PLLA causes M2 polarization by increasing IL-4 and IL-13 levels and upregulating TGF-ß expression and collagen synthesis in aged skin.

Poly-D,L-Lactic Acid Stimulates Angiogenesis and Collagen Synthesis in Aged Animal Skin.

Angiogenesis promotes rejuvenation in multiple organs, including the skin. Heat shock protein 90 (HSP90), hypoxia-inducible factor-1 alpha (HIF-1α), and vascular endothelial growth factor (VEGF) are proangiogenic factors that stimulate the activities of phosphoinositide 3-kinase (PI3K), protein kinase B (AKT), and extracellular signal-regulated kinase 1/2 (ERK1/2). Poly-D,L-lactic acid (PDLLA), polynucleotide (PN), and calcium hydroxyapatite (CaHA) are dermal fillers that stimulate the synthesis of dermal collagen. However, it is not yet known whether these compounds promote angiogenesis, which leads to skin rejuvenation. Here, we evaluated whether PDLLA, PN, and CaHA stimulate angiogenesis and skin rejuvenation using H2O2-treated senescent macrophages and endothelial cells as an in vitro model for skin aging, and we used young and aged C57BL/6 mice as an in vivo model. Angiogenesis was evaluated via endothelial cell migration length, proliferation, and tube formation after conditioned media (CM) from senescent macrophages was treated with PDLLA, PN, or CaHA. Western blot showed decreased expression levels of HSP90, HIF-1α, and VEGF in senescent macrophages, but higher expression levels of these factors were found after treatment with PDLLA, PN, or CaHA. In addition, after exposure to CM from senescent macrophages treated with PDLLA, PN, or CaHA, senescent endothelial cells expressed higher levels of VEGF receptor 2 (VEGFR2), PI3K, phosphorylated AKT (pAKT), and phosphorylated ERK1/2 (pERK1/2) and demonstrated greater capacities for cell migration, cell proliferation, and tube formation. Based on the levels of 4-hydroxy-2-nonenal, the oxidative stress level was lower in the skin of aged mice injected with PDLLA, PN, or CaHA, while the tumor growth factor (TGF)-ß1, TGF-ß2, and TGF-ß3 expression levels; the density of collagen fibers; and the skin elasticity were higher in the skin of aged mice injected with PDLLA, PN, or CaHA. These effects were greater in PDLLA than in PN or CaHA. In conclusion, our results are consistent with the hypothesis that PDLLA stimulates angiogenesis, leading to the rejuvenation of aged skin. Our study is the first to show that PDLLA, PN, or CaHA can result in angiogenesis in the aged skin, possibly by increasing the levels of HSP90, HIF-1α, and VEGF and increasing collagen synthesis.

Radiofrequency Irradiation Attenuated UVB-Induced Skin Pigmentation by Modulating ATP Release and CD39 Expression.

Hyperpigmentation stimulated by ultraviolet (UV)-induced melanin overproduction causes various cosmetic problems. UV radiation's activation of the cyclic adenosine monophosphate (cAMP)-mediated cAMP-dependent protein kinase (PKA)/cAMP response element-binding protein (CREB)/microphthalmia-associated transcription factor (MITF) pathway is the main pathway for melanogenesis. However, the secretion of adenosine triphosphate (ATP) from keratinocytes due to UV radiation also leads to melanogenesis. Adenosine, converted from ATP by CD39 and CD73, can activate adenylate cyclase (AC) activity and increase intracellular cAMP expression. cAMP-mediated PKA activation results in dynamic mitochondrial changes that affect melanogenesis via ERK. We evaluated whether radiofrequency (RF) irradiation could decrease ATP release from keratinocytes and suppress the expression of CD39, CD73, and A2A/A2B adenosine receptors (ARs) and the activity of AC and downregulate the PKA/CREB/MITF pathway, which would eventually decrease melanogenesis in vitro in UV-irradiated cells and animal skin. Our results indicate that RF decreased ATP release from UVB-irradiated keratinocytes. When conditioned media (CM) from UVB-irradiated keratinocytes (CM-UVB) were administered to melanocytes, the expressions of CD39, CD73, A2A/A2BARs, cAMP, and PKA increased. However, the expression of these factors decreased when CM from UVB and RF-irradiated keratinocytes (CM-UVB/RF) was administered to melanocytes. The phosphorylation of DRP1 at Ser637, which inhibits mitochondrial fission, increased in UVB-irradiated animal skin and was decreased by RF irradiation. The expression of ERK1/2, which can degrade MITF, was increased using RF treatment in UVB-irradiated animal skin. Tyrosinase activity and melanin levels in melanocytes increased following CM-UVB administration, and these increases were reversed after CD39 silencing. Tyrosinase activity and melanin levels in melanocytes were decreased by CM-UVB/RF irradiation. In conclusion, RF irradiation decreased ATP release from keratinocytes and the expressions of CD39, CD73, and A2A/A2BARs, which decreased AC activity in melanocytes. RF irradiation downregulated the cAMP-mediated PKA/CREB/MITF pathway and tyrosinase activity, and these inhibitory effects can be mediated via CD39 inhibition.

The Extracellular Matrix Vitalizer RATM Increased Skin Elasticity by Modulating Mitochondrial Function in Aged Animal Skin.

Oxidative stress-induced cellular senescence and mitochondrial dysfunction result in skin aging by increasing ECM levels-degrading proteins such as MMPs, and decreasing collagen synthesis. MMPs also destroy the basement membrane, which is involved in skin elasticity. The extracellular matrix vitalizer RATM (RA) contains various antioxidants and sodium hyaluronate, which lead to skin rejuvenation. We evaluated whether RA decreases oxidative stress and mitochondrial dysfunction, eventually increasing skin elasticity in aged animals. Oxidative stress was assessed by assaying NADPH oxidase activity, which is involved in ROS generation, and the expression of SOD, which removes ROS. NADPH oxidase activity was increased in aged skin and decreased by RA injection. SOD expression was decreased in aged skin and increased by RA injection. Damage to mitochondrial DNA and mitochondrial fusion markers was increased in aged skin and decreased by RA. The levels of mitochondrial biogenesis markers and fission markers were decreased in aged skin and increased by RA. The levels of NF-κB/AP-1 and MMP1/2/3/9 were increased in aged skin and decreased by RA. The levels of TGF-ß, CTGF, and collagen I/III were decreased in aged skin and increased by RA. The expression of laminin and nidogen and basement membrane density were decreased in aged skin and increased by RA. RA increased collagen fiber accumulation and elasticity in aged skin. In conclusion, RA improves skin rejuvenation by decreasing oxidative stress and mitochondrial dysfunction in aged skin.

High-Intensity Focused Ultrasound Decreases Subcutaneous Fat Tissue Thickness by Increasing Apoptosis and Autophagy.

High-intensity focused ultrasound (HIFU) leads to decreased subcutaneous adipose tissue (SAT) thickness via heat-induced adipocyte necrosis. Heat can induce adipocyte apoptosis and autophagy, and it is known that nuclear or mitochondrial p53 is involved in apoptosis and autophagy. However, whether HIFU leads to apoptosis or autophagy is unclear. We evaluated whether HIFU decreases SAT thickness via p53-related apoptosis or autophagy in high-fat diet (HFD)-fed animals. The expression of nuclear and mitochondrial p53 was increased by HIFU. HIFU also led to decreased expression of BCL2/BCL-xL (an antiapoptotic signal), increased expression of BAX/BAK (an apoptotic signal), increased levels of cleaved caspase 3/9, and increased numbers of apoptotic cells as evaluated by TUNEL assay. Furthermore, HIFU led to increased levels of ATG5, BECN1, and LC3II/LC3I, and decreased levels of p62, a marker of increased autophagy. The thickness of SAT was decreased by HIFU. In conclusion, HIFU led to nuclear and mitochondrial p53 expression, which led to apoptosis and autophagy, and eventually decreased SAT thickness in HFD-fed animals.

Rice Germ Ameliorated Chronic Unpredictable Mild Stress-Induced Depressive-like Behavior by Reducing Neuroinflammation.

Stress-induced neuroinflammation is widely regarded as one of the primary causes of depression. Gamma-aminobutyric acid (GABA)-enriched foods relieve stress and reduce inflammatory reactions. This study aimed to evaluate whether rice germ with 30% GABA (RG) reduced neuroinflammation in mice exposed to chronic unpredictable mild stress (CUMS). CUMS mice were administered 40, 90, and 140 mg/kg of RG. CUMS increased serum and hypothalamic pro-inflammatory cytokine (TNF-α and IL-6) levels, which were decreased by RG. In the hypothalamus, CUMS elevated M1-type microglia markers of CD86 and NF-κB, whereas RG lowered these levels. The expression levels of NLRP3 inflammasome complex (NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain, and caspase-1), IL-1ß, and IL-18 were increased in the hypothalamus of CUMS mice and decreased by RG. RG attenuated depressive-like behaviors in CUMS mice, as measured by the forced swim test and tail suspension test. In conclusion, RG decreased hypothalamic inflammation-related signals, such as TNF-α, IL-6, M1 polarization, NF-κB, NLRP3 inflammasome complex, caspase-1, IL-1ß, and IL-18, to diminish depressive-like behavior.

Exogenous 8-hydroxydeoxyguanosine attenuates doxorubicin-induced cardiotoxicity by decreasing pyroptosis in H9c2 cardiomyocytes.

Doxorubicin (DOX), which is widely used in cancer treatment, can induce cardiomyopathy. One of the main mechanisms whereby DOX induces cardiotoxicity involves pyroptosis through the NLR family pyrin domain containing 3 (NLRP3) inflammasome and gasdermin D (GSDMD). Increased NAPDH oxidase (NOX) and oxidative stress trigger pyroptosis. Exogenous 8-hydroxydeoxyguanosine (8-OHdG) decreases reactive oxygen species (ROS) production by inactivating NOX. Here, we examined whether 8-OHdG treatment can attenuate DOX-induced pyroptosis in H9c2 cardiomyocytes. Exposure to DOX increased the peroxidative glutathione redox status and NOX1/2/4, toll-like receptor (TLR)2/4, and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) expression, while an additional 8-OHdG treatment attenuated these effects. Furthermore, DOX induced higher expression of NLRP3 inflammasome components, including NLRP3, apoptosis-associated speck-like protein containing a c-terminal caspase recruitment domain (ASC), and pro-caspase-1. Moreover, it increased caspase-1 activity, a marker of pyroptosis, and interleukin (IL)-1ß expression. All these effects were attenuated by 8-OHdG treatment. In addition, the expression of the cardiotoxicity markers, atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) was increased by DOX, whereas the increase of ANP and BNP induced by DOX treatment was reversed by 8-OHdG. In conclusion, exogenous 8-OHdG attenuated DOX-induced pyroptosis by decreasing the expression of NOX1/2/3, TLR2/4, and NF-κB. Thus, 8-OHdG may attenuate DOX-induced cardiotoxicity through the inhibition of pyroptosis.

Addition of oh8dG to Cardioplegia Attenuated Myocardial Oxidative Injury through the Inhibition of Sodium Bicarbonate Cotransporter Activity.

The biomarker 8-hydroxy-2'-deoxyguanosine (oh8dG) is derived from oxidized nucleic acids or products of oxidant-mediated DNA damage. Enhanced sodium bicarbonate cotransporter (NBC) activity is caused by reactive oxygen species (ROS) production in ventricular myocytes. Thus, we hypothesized that cardioplegia-solution-mediated ROS generation may be involved in the regulation of NBC activity in cardiomyocytes and that oh8dG treatment may modulate ROS and associated NBC activity. Langendorff-free cardioplegia-arrested cardiac strips and cardiomyocytes were isolated to determine the NBC activity and effects of oh8dG on oxidative-stress-mediated cardiac damage markers. We first determined the histidine-tryptophan-ketoglutarate (HTK) solution mediated NBC activity in cardiac strips and cells. The oh8dG treatment attenuated NBC activity in the electroneutral or electrogenic form of NBC. Additionally, exposure to HTK solution induced ROS, whereas co-administration of oh8dG attenuated ROS-mediated NBC activity, reduced ROS levels, and decreased the expression of apoptotic markers and fibrosis-associated proteins in cardiac cells. The oh8dG-administrated cardiac tissues were also protected from enhanced HTK-induced damage markers, heat shock protein 60 and polyADP-ribose. Our results show that oh8dG has a protective role against myocardial oxidative damage and provides a useful treatment strategy for restoring cardiac function.

Hyperglycemia and Hypoglycemia Are Associated with In-Hospital Mortality among Patients with Coronavirus Disease 2019 Supported with Extracorporeal Membrane Oxygenation.

Metabolic abnormalities, such as preexisting diabetes or hyperglycemia or hypoglycemia during hospitalization aggravated the severity of COVID-19. We evaluated whether diabetes history, hyperglycemia before and during extracorporeal membrane oxygenation (ECMO) support, and hypoglycemia were risk factors for mortality in patients with COVID-19. This study included data on 195 patients with COVID-19, who were aged ≥19 years and were treated with ECMO. The proportion of patients with diabetes history among nonsurvivors was higher than that among survivors. Univariate Cox regression analysis showed that in-hospital mortality after ECMO support was associated with diabetes history, renal replacement therapy (RRT), and body mass index (BMI) < 18.5 kg/m2. Glucose at admission >200 mg/dL and glucose levels before ventilator >200 mg/dL were not associated with in-hospital mortality. However, glucose levels before ECMO >200 mg/dL and minimal glucose levels during hospitalization <70 mg/dL were associated with in-hospital mortality. Multivariable Cox regression analysis showed that glucose >200 mg/dL before ECMO and minimal glucose <70 mg/dL during hospitalization remained risk factors for in-hospital mortality after adjustment for age, BMI, and RRT. In conclusion, glucose >200 mg/dL before ECMO and minimal glucose level <70 mg/dL during hospitalization were risk factors for in-hospital mortality among COVID-19 patients who underwent ECMO.

The Combination of Niacinamide, Vitamin C, and PDRN Mitigates Melanogenesis by Modulating Nicotinamide Nucleotide Transhydrogenase.

Nicotinamide nucleotide transhydrogenase (NNT) is involved in decreasing melanogenesis through tyrosinase degradation induced by cellular redox changes. Nicotinamide is a component of coenzymes, such as NAD+, NADH, NADP+, and NADPH, and its levels are modulated by NNT. Vitamin C and polydeoxyribonucleotide (PDRN) are also known to decrease skin pigmentation. We evaluated whether a mixture of nicotinamide, vitamin C, and PDRN (NVP-mix) decreased melanogenesis by modulating mitochondrial oxidative stress and NNT expression in UV-B-irradiated animals and in an in vitro model of melanocytes treated with conditioned media (CM) from UV-B-irradiated keratinocytes. The expression of NNT, GSH/GSSG, and NADPH/NADP+ in UV-B-irradiated animal skin was significantly decreased by UV-B radiation but increased by NVP-mix treatment. The expression of NNT, GSH/GSSG, and NADPH/NADP+ ratios decreased in melanocytes after CM treatment, although they increased after NVP-mix administration. In NNT-silenced melanocytes, the GSH/GSSG and NADPH/NADP+ ratios were further decreased by CM compared with normal melanocytes. NVP-mix decreased melanogenesis signals, such as MC1R, MITF, TYRP1, and TYRP2, and decreased melanosome transfer-related signals, such as RAB32 and RAB27A, in UV-B-irradiated animal skin. NVP-mix also decreased MC1R, MITF, TYRP1, TYRP2, RAB32, and RAB27A in melanocytes treated with CM from UV-irradiated keratinocytes. The expression of MC1R and MITF in melanocytes after CM treatment was unchanged by NNT silencing. However, the expression of TYRP1, TYRP2, RAB32, and RAB27A increased in NNT-silenced melanocytes after CM treatment. NVP-mix also decreased tyrosinase activity and melanin content in UV-B-irradiated animal skin and CM-treated melanocytes. In conclusion, NVP-mix decreased mitochondrial oxidative stress by increasing NNT expression and decreased melanogenesis by decreasing MC1R/MITF, tyrosinase, TYRP1, and TYRP2.

High-Intensity Focused Ultrasound Induces Adipogenesis via Control of Cilia in Adipose-Derived Stem Cells in Subcutaneous Adipose Tissue.

During skin aging, the volume of subcutaneous adipose tissue (sWAT) and the adipogenesis potential of adipose-derived stem cells (ASCs) decrease. It is known that the shortening of cilia length by pro-inflammatory cytokines is related to the decreased adipogenic differentiation of ASCs via increase in Wnt5a/ß-catenin. High-intensity focused ultrasound (HIFU) is known to upregulate heat shock proteins (HSP), which decrease levels of pro-inflammatory cytokines. In this study, we evaluated whether HIFU modulates the cilia of ASCs by upregulating HSP70 and decreasing inflammatory cytokines. HIFU was applied at 0.2 J to rat skin, which was harvested at 1, 3, 7, and 28 days. All results for HIFU-applied animals were compared with control animals that were not treated. HIFU increased expression of HSP70 and decreased expression of NF-κB, IL-6, and TNF-α in sWAT. HIFU decreased the expression of cilia disassembly-related factors (AurA and HDAC9) in ASCs. Furthermore, HIFU increased the expression of cilia assembly-related factors (KIF3A and IFT88), decreased that of WNT5A/ß-catenin, and increased that of the adipogenesis markers PPARγ and CEBPα in sWAT. HIFU increased the number of adipocytes in the sWAT and the thickness of sWAT. In conclusion, HIFU could selectively increase sWAT levels by modulating the cilia of ASCs and be used for skin rejuvenation.