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Accumulation of somatic mutations in the mitochondrial genome (mtDNA) has long been proposed as a possible mechanism of mitochondrial and tissue dysfunction that occurs during aging. A thorough characterization of age-associated mtDNA somatic mutations has been hampered by the limited ability to detect low-frequency mutations. Here, we used Duplex Sequencing on eight tissues of an aged mouse cohort to detect >89,000 independent somatic mtDNA mutations and show significant tissue-specific increases during aging across all tissues examined which did not correlate with mitochondrial content and tissue function. G→A/C→T substitutions, indicative of replication errors and/or cytidine deamination, were the predominant mutation type across all tissues and increased with age, whereas G→T/C→A substitutions, indicative of oxidative damage, were the second most common mutation type, but did not increase with age regardless of tissue. We also show that clonal expansions of mtDNA mutations with age is tissue- and mutation type-dependent. Unexpectedly, mutations associated with oxidative damage rarely formed clones in any tissue and were significantly reduced in the hearts and kidneys of aged mice treated at late age with elamipretide or nicotinamide mononucleotide. Thus, the lack of accumulation of oxidative damage-linked mutations with age suggests a life-long dynamic clearance of either the oxidative lesions or mtDNA genomes harboring oxidative damage.

Due to the increased morbidity and mortality by fungal infections and the emergence of severe antifungal resistance, there is an urgent need for new antifungal agents. Here, we screened for antifungal activity in our in-house library through the minimum inhibitory concentration test and derived two hit compounds with moderate antifungal activities. The hit compounds' antifungal activities and drug-like properties were optimized by substituting various aryl ring, alkyl chain, and methyl groups. Among the optimized compounds, 22h was the most promising candidate with good drug-like properties and exhibited potent fast-acting fungicidal antifungal effects against various fungal pathogens and synergistic antifungal activities with some known antifungal drugs. Additionally, 22h was further confirmed to disturb fungal cell wall integrity by activating multiple cell wall integrity pathways. Furthermore, 22h exerted significant antifungal efficacy in both the subcutaneous infection mouse model and ex vivo human nail infection model.

Particulate matters (PMs) from polluted air cause diverse pulmonary and cardiovascular diseases, including lung inflammation. While the fruits (Goji) of Lycium trees are commonly consumed as traditional medicine and functional food ingredients, the majority of their roots are discarded as by-products. To enhance the industrial applicability of Lycium roots, we prepared an ethanol extract (named GR30) of L. chinense Miller roots and evaluated its potential protective effects against particulate matter 10 (PM10)-induced inflammation and immune cell death. The GR30 treatment (0–500 μg/mL) significantly attenuated the PM10-induced cell cycle arrest, DNA fragmentation and mitochondria-dependent apoptosis in RBL-2H3 basophil cells. GR30 also significantly antagonized the PM10-induced expression of proinflammatory cytokines (IL-4, IL-13, and TNF-α) and COX2 expression through downregulation of MAPKs (ERK and JNK) signalling pathway. Oral administration of GR30 (200–400 mg/kg) to PM10 (20 mg/mL)-challenged mice significantly reduced the serum levels of IgE and the expression of TNF-α and Bax in lung tissues, which were elevated by PM10 exposure. These results revealed that the ethanolic extract (GR30) of L. chinense Miller roots exhibited anti-inflammatory and cyto-protective activity against PM10-induced inflammation and basophil cell death, and thus, it would be useful in functional food industries to ameliorate PM-mediated damage to respiratory and immune systems.

Accumulation of somatic mutations in the mitochondrial genome (mtDNA) during aging has long been proposed as a possible mechanism of mitochondrial and tissue dysfunction. A thorough characterization of age-associated mtDNA somatic mutations has been hampered by the limited ability to detect low frequency mutations. Here, we used Duplex Sequencing on eight tissues of an aged mouse cohort to detect >89,000 independent somatic mtDNA mutations and show significant tissue-specific increases during aging across all tissues examined which did not correlate with mitochondrial content and tissue function. G→A/C→T substitutions, indicative of replication errors and/or cytidine deamination, were the predominant mutation type across all tissues and increased with age, whereas G→T/C→A substitutions, indicative of oxidative damage, were the second most common mutation type, but did not increase with age regardless of tissue. We also show that clonal expansions of mtDNA mutations with age is tissue and mutation type dependent. Unexpectedly, mutations associated with oxidative damage rarely formed clones in any tissue and were significantly reduced in the hearts and kidneys of aged mice treated at late age with Elamipretide or nicotinamide mononucleotide. Thus, the lack of accumulation of oxidative damage-linked mutations with age indicates a life-long dynamic clearance of either the oxidative lesions or mtDNA genomes harboring oxidative damage.

Monoamine oxidase-B (MAO-B) is a well-established therapeutic target for Parkinson’s disease (PD); however, previous clinical studies on currently available irreversible MAO-B inhibitors have yielded disappointing neuroprotective effects. Here, we tested the therapeutic potential of KDS2010, a recently synthesized potent, selective, and reversible MAO-B inhibitor in multiple animal models of PD. We designed and synthesized a series of α-aminoamide derivatives and found that derivative KDS2010 exhibited the highest potency, specificity, reversibility, and bioavailability (> 100%). In addition, KDS2010 demonstrated significant neuroprotective and anti-neuroinflammatory efficacy against nigrostriatal pathway destruction in the mouse MPTP model of parkinsonism. Treatment with KDS2010 also alleviated parkinsonian motor dysfunction in 6-hydroxydopamine-induced and A53T mutant α-synuclein overexpression rat models of PD. Moreover, KDS2010 showed virtually no toxicity or side effects in non-human primates. KDS2010 could be a next-generation therapeutic candidate for PD. Supplementary Information The online version contains supplementary material available at 10.1007/s13311-021-01097-4.

β cell regeneration is necessary to cure patients with type 1 diabetes (T1D) whose β cells are destroyed by immune cells. Although insulin therapy can control blood glucose levels, it must be administered throughout life and occurs several side effects such as hypoglycemia. New β cell can be generated through neogenesis, β cell replication or transdifferentiation from other cells in diabetic animals. In addition to β cell regeneration, immunosuppression is another important mechanism to prevent β cell destruction, but currently any drugs haven’t been approved as immunosuppressants for T1D treatments yet. A novel 9-mer peptide, Shiloah 1000 (S1K) , has dual functions of β cell regeneration and immunosuppression. In streptozotocin-induced hyperglycemic mouse model, the number of mice recovered to normoglycemia was increased by the combined treatment of S1K and insulin compared to S1K or insulin alone. In addition, the combined treatment more increased the number of β cells than S1K or insulin alone. Interestingly, insulin/glucagon double-positive cells were increased by both combined and S1K alone treatments. The increase in the number of mice recovered to normoglycemia is considered to be due to β cell regeneration through α- to β-cell transdifferentiation by S1K. In the NOD mouse model, the combined treatment of S1K and insulin suppressed hyperglycemia more than insulin alone. In addition, the serum C-peptide levels were increased by both combined and S1K treatments, but not by insulin treatment. The increase in the serum C-peptide level suggest that β cells remain undestroyed by immunosuppression. Taken together, our data show that S1K, as a drug candidate for T1D treatment in combination with insulin reduces blood glucose levels in the T1D mouse models through β cell regeneration and immunosuppression, suggesting a potential role in preventing and curing T1D. Disclosure Y. Lee: Employee; Ensolbiosciences. H. Kim: Employee; Ensolbiosciences. J. Kim: Employee; Ensol Bioscience. Y. Jang: Employee; Ensolbiosciences.

Background Variations by hospital and region in the selection of an early invasive strategy (EIS) after non–ST-segment elevation myocardial infarction (NSTEMI) in patients with high-risk criteria are unknown. Methods We evaluated the data of 7037 patients with NSTEMI from 20 hospitals of 3 regions from the Korean Acute Myocardial Infarction Registry–National Institute of Health database. We used hierarchical generalized linear mixed-models to estimate region- and hospital-level variation in the selection of an EIS after adjusting for patient-level high-risk criteria. We explored the variation using the median rate ratio (MRR), which estimates the relative difference in the risk ratios of two hypothetically identical patients at two different sites. Results An EIS was selected in 84.4% of patients. At the hospital level, the median selection rate was 80.4%. At the region level, the median selection rate was 74.9% in the east region, 81.3% in the north region, and 83.9% in the west region, respectively. After adjusting for patient-level covariates, we found significant hospital- (MRR 2.19, 95% confidence interval [CI]: 1.74–3.03) and region-level (MRR 1.88, 95%CI: 1.26–5.44) variation in the selection of an EIS. Among patient-level factors, male sex, ongoing chest pain, history of coronary artery disease or acute heart failure, and GRACE risk score > 140 were independently associated with the selection of an EIS. Conclusions We observed significant hospital- and region-level variation in the selection of an EIS after NSTEMI in high-risk patients. Quality improvement efforts are required to standardize decision making and to improve clinical outcomes.

Oxidative catabolism of monoamine neurotransmitters by monoamine oxidases (MAOs) produces reactive oxygen species (ROS), which contributes to neuronal cells’ death and also lowers monoamine neurotransmitter levels. In addition, acetylcholinesterase activity and neuroinflammation are involved in neurodegenerative diseases. Herein, we aim to achieve a multifunctional agent that inhibits the oxidative catabolism of monoamine neurotransmitters and, hence, the detrimental production of ROS while enhancing neurotransmitter levels. Such a multifunctional agent might also inhibit acetylcholinesterase and neuroinflammation. To meet this end goal, a series of aminoalkyl derivatives of analogs of the natural product hispidol were designed, synthesized, and evaluated against both monoamine oxidase-A (MAO-A) and monoamine oxidase-B (MAO-B). Promising MAO inhibitors were further checked for the inhibition of acetylcholinesterase and neuroinflammation. Among them, compounds 3aa and 3bc were identified as potential multifunctional molecules eliciting submicromolar selective MAO-B inhibition, low-micromolar AChE inhibition, and the inhibition of microglial PGE2 production. An evaluation of their effects on memory and cognitive impairments using a passive avoidance test confirmed the in vivo activity of compound 3bc, which showed comparable activity to donepezil. In silico molecular docking provided insights into the MAO and acetylcholinesterase inhibitory activities of compounds 3aa and 3bc. These findings suggest compound 3bc as a potential lead for the further development of agents against neurodegenerative diseases.

The proper administration of melatonin has well been documented to induce testicular regression in seasonal breeding animals. The subcutaneous injections of melatonin in the afternoon, not in the morning, consistently occurred testicular involution in the male Syrian (golden) hamsters whose reproductive activity is regulated by the photoperiod. But the effects of daily melatonin via gavage have not been estimated. Golden hamsters housed in long photoperiod (LP) were divided into 5 groups: the control animals housed in LP or in short photoperiod (SP) and animals treated daily with low (15 μg), middle (150 μg), and high dosages (1,500 μg) of pure melatonin by using gavage in the evening for 8 weeks. As results, LP control animals had large testes and SP controls displayed small and entirely regressed testes. The animals treated with various dosages of melatonin showed collectively degenerating effects on the weights of testes, epididymides, and seminal vesicles in the middle and high dosage groups, with the individual differences as well. The high dosages induced testicular regression in more proportion than the middle dosages did. The low dosage had large testes like the LP control animals. The small and inactive testes shown in some animals of both middle and high groups presented the complete regression as those of the animals maintained in SP. These results strongly suggest that the administrations of melatonin lead to testicular involution in the male golden hamsters when it is administered through gavage.

Sphingosine-1-phosphate-1 (S1P1) receptor agonists are well-known drugs for treating multiple sclerosis (MS) caused by autoreactive lymphocytes that attack the myelin sheath. Therefore, an effective therapeutic strategy is to reduce the lymphocytes in the blood by inducing S1P1 receptor internalization. We synthesized serinolamide A, a natural product of the sea, and performed S1P1 receptor internalization assay to evaluate functionally antagonistic S1P1 receptor agonist activity. In order to synthesize derivatives with better efficacy than serinolamide A and B, new derivatives were synthesized by introducing the phenyl ring moiety of fingolimod. Among them, compounds 19 and 21 had superior S1P1 agonistic effects to serinolamide. We also confirmed that compound 19 effectively inhibited lymphocyte outflow in peripheral lymphocyte count (PLC) assay.

We measure the frictional drag-reducing property of various superhydrophobic metal oxide nanostructures by quantifying their effective slip length. Scalable chemical methods tailored to each metal substrate are applied to grow oxide nanostructures on copper (Cu), aluminum (Al), and titanium (Ti), respectively. In particular, three different types of oxide nanostructures are grown on the titanium substrate by changing the chemical composition to investigate the morphological influence on the slip length. Microchannels containing metal oxide nanostructures are fabricated based on the microfluidic sticker method, while the slip length is unambiguously determined by measuring the ratio of the volume flow rate over the superhydrophobic surface to that over the flat surface simultaneously. The slip length is measured to be 6.8 ± 1.4 μm on Cu nanostructures, while it is measured to be 2.5 ± 0.6 μm on Al nanostructures. For Ti nanostructures, the measured slip lengths range from 1 to 2.5 ± 0.5 μm, where they increase proportionally with the structural pitch of the nanostructures, agreeing with the theoretical predictions. We believe that our results will be useful in applying scalable low-cost metal oxide nanostructures to underwater applications by providing their frictional characteristics.

Background: This study aimed to investigate the incidences of and risk factors for perioperative events following anticoagulant discontinuation in patients with non-valvular atrial fibrillation (NVAF) undergoing non-cardiac surgery. Methods: A total of 216 consecutive patients who underwent cardiac consultation for suspending perioperative anticoagulants were enrolled. A perioperative event was defined as a composite of thromboembolism and major bleeding. Results: The mean anticoagulant discontinuation duration was 5.7 (±4.2) days and was significantly longer in the warfarin group (p

Herein, two new series of N-substituted indole-based analogues were rationally designed, synthesized via microwave heating technology, and evaluated as noteworthy MAO-B potential inhibitors. Compared to the reported indazole-based hits VI and VII, compounds 4b and 4e exhibited higher inhibitory activities over MAO-B with IC50 values of 1.65 and 0.78 µM, respectively. When compared to the modest selectivity index of rasagiline (II, a well-known MAO-B inhibitor, SI > 50), both 4b and 4e also showed better selectivity indices (SI > 60 and 120, respectively). A further kinetic evaluation of the most potent derivative (4e) displayed a competitive mode of inhibition (inhibition constant (Ki)/MAO-B = 94.52 nM). Reasonable explanations of the elicited biological activities were presented via SAR study and molecular docking simulation. Accordingly, the remarkable MAO-B inhibitory activity of 4e (N-(1-(3-fluorobenzoyl)-1H-indol-5-yl)pyrazine-2-carboxamide), with its selectivity and competitive inhibition, advocates its potential role as a promising lead worthy of further optimization.

The sphingosine-1-phosphate-1 (S1P

Multifunctional molecules might offer better treatment of complex multifactorial neurological diseases. Monoaminergic pathways dysregulation and neuroinflammation are common convergence points in diverse neurodegenerative and neuropsychiatric disorders. Aiming to target these diseases, polypharmacological agents modulating both monoaminergic pathways and neuroinflammatory were addressed. A library of analogues of the natural product hispidol was prepared and evaluated for inhibition of monoamine oxidases (MAOs) isoforms. Several molecules emerged as selective potential MAO B inhibitors. The most promising compounds were further evaluated in vitro for their impact on microglia viability, induced production of proinflammatory mediators and MAO-B inhibition mechanism. Amongst tested compounds, 1p was a safe potent competitive reversible MAO-B inhibitor and inhibitor of microglial production of neuroinflammatory mediators; NO and PGE2. In-silico study provided insights into molecular basis of the observed selective MAO B inhibition. This study presents compound 1p as a promising lead compound for management of neurodegenerative disease.

Atraumatic splenic rupture (ASR) in a patient undergoing peritoneal dialysis (PD) is uncommon, but can be life-threatening. According to recent systematic reviews, the major causes of ASR are 1) neoplastic (30.3%), 2) infectious (27.3%), 3) non-in-fectious inflammatory (20.0%), 4) iatrogenic (9.2%), 5) mechanical (6.8%), and 6) idiopathic (6.4%). It is diagnosed by imaging studies, most commonly ultrasonography and computed tomography (CT). Due to its rarity, the early diagnosis of ASR is difficult, and no standard treatment has been described. Here, we report a case of idiopathic ASR in a patient undergoing PD. The diagnosis was established by abdominal CT scan, and splenectomy was performed. Thus, hemoperitoneum in a PD patient should raise suspi-cion of ASR. Early diagnosis and appropriate treatment will lead to a better outcome. (Korean J Med 2019;94:526-529)

The morphogenetically matured spermatozoa (sperm) are generated in the testes by the spermatogenesis. They travel male reproductive tract with many substances secreted from the accessory reproductive organs. One of the substances is the semenogelin (SEMG) released from the seminal vesicles that is involved in the post-testicular maturation. The expression of SEMG gene was investigated in seminal vesicle tissues of sexually matured and regressed male Syrian hamsters by reverse transcription polymerase chain reaction (RT-PCR). The SEMG gene was uniquely identified in the seminal vesicles of the matured Syrian hamsters and compared to the genes reported previously. But the expression of SEMG gene was not observed in reproductively and completely regressed testes of Syrian hamsters. These results indicate that the expressions of the SEMG gene are related to the reproductive capability in the male Syrian hamsters.

It has been known that the fear of contagion during the coronavirus disease 2019 (COVID-19) creates time delays with subsequent impact on mortality in patients with acute myocardial infarction (AMI). However, difference of time delay and clinical outcome in patients with ST-segment elevation myocardial infarction (STEMI) or non-STEMI between the COVID-19 pandemic and pre-pandemic era has not been fully investigated yet in Korea. The aim of this study was to investigate the impact of COVID-19 pandemic on time delays and clinical outcome in patients with STEMI or non-STEMI compared to the same period years prior.A total of 598 patients with STEMI (n = 195) or non-STEMI (n = 403) who underwent coronary angiography during the COVID-19 pandemic (February 1 to April 30, 2020) and pre-pandemic era (February 1 to April 30, 2017, 2018, and 2019) were analyzed in this study. Main outcomes were the incidence of time delay, cardiac arrest, and in-hospital death.There was 13.5% reduction in the number of patients hospitalized with AMI during the pandemic compared to pre-pandemic era. In patients with STEMI, door to balloon time tended to be longer during the pandemic compared to pre-pandemic era (55.7 ± 12.6 minutes vs. 60.8 ± 13.0 minutes,During the COVID-19 pandemic, there has been a considerable reduction in hospital admissions for AMI, time delay, and underuse of ACE-I/ARBs for the management of AMI, and this might be closely associated with the excess death in Korea.