Mitochondrial Cytochrome C Oxidase Research Articles

Oxazolidinone antibiotics impair ex vivo megakaryocyte differentiation from hematopoietic progenitor cells and their maturation into platelets.

Oxazolidinones (linezolid and tedizolid) adverse reactions include thrombocytopenia, the mechanism of which is still largely unknown. In cultured cells, oxazolidinones impair mitochondrial protein synthesis and oxidative metabolism. As mitochondrial activity is essential for megakaryocyte differentiation and maturation into platelets, we examined whether oxazolidinones impair these processes ex vivo and alter, in parallel, the activity of mitochondrial cytochrome c-oxidase (CYTOX; enzyme partly encoded by the mitochondrial genome) and cell morphology. Human CD34+ cells were isolated, incubated with cytokines (up to 14 days) and clinically relevant oxazolidinone concentrations or in control conditions, and used for (i) clonogenic assays [counting of megakaryocyte (CFU-Mk), granulocyte-monocyte (CFU-GM), burst-forming unit-erythroid (BFU-E) colonies]; (ii) the measure of the expression of megakaryocyte surface antigens (CD34 to CD41 and CD42); (iii) counting of proplatelets; (iv) the measurement of CYTOX activity; and (v) cell morphology (optic and electron microscopy). Oxazolidinones caused a significant decrease in BFU-E but not CFU-Mk or CFU-GM colonies. Yet, the megakaryocytic lineage was markedly affected, with a decreased differentiation of CD34+ into CD41+/CD42+ cells, an abolition of proplatelet formation and striking decrease in the numbers of large polylobulated nucleus megakaryocytes, with a complete loss of intracellular demarcation membrane system, disappearance of mitochondria, and suppression of CYTOX activity. These alterations were more marked in cells incubated with tedizolid than linezolid. These data suggest that oxazolidinones may induce thrombocytopenia by impairing megakaryocytic differentiation through mitochondrial dysfunction. Pharmacological interventions to prevent this toxicity might therefore be difficult as mitochondrial toxicity is most probably inherently linked to their antibacterial activity.

First molecular description of Neorhadinorhynchus nudus (Acanthocephala: Cavisomidae) from fish in the pacific coast of Vietnam, with notes on biogeography.

Neorhadinorhynchus nudus (Harada, 1938) Yamaguti, 1939 (Cavisomidae) was morphologically described from the frigate tuna Auxis thazard (Lacépède) (Scombridae) in Nha Trang, Pacific south Vietnam. Females of N. nudus were fully described for the first time in the Pacific. Its original inadequate description as Rhadinorhynchus nudus (Harada, 1938) was corrected in material from Fiji Island, the Red Sea and Pacific Vietnam and errors in the text and line drawings of Harada were repeated in subsequent major publications where it underwent considerable nomenclature changes. New descriptive and biogeographical notes are included. We also provided here the molecular characterization of the nuclear gene (18S) and the mitochondrial cytochromecoxidase subunit 1 (cox1) sequence data ofN. nudus. Furthermore, to elucidate the phylogenetic relationship of N. nudus within the family Cavisomidae and with other isolates were performed incorporating nuclear (18S) and mitochondrial (cox1) sequence data using maximum likelihood (ML) and Bayesian inference (BI). The phylogenetic results showed thatN. nudus has a relationship withother isolates of the same species and the median-joining network showed the pattern of haplotypes that reflected the structure of the populations.

Photobiomodulation increases brain metabolic activity through a combination of 810 and 660 wavelengths: a comparative study in male and female rats

Photobiomodulation (PBM), an emerging and non-invasive intervention, has been shown to benefit the nervous system by modifying the mitochondrial cytochrome c-oxidase (CCO) enzyme, which has red (620–680 nm) or infrared (760–825 nm) spectral absorption peaks. The effect of a single 810-nm wavelength with a combination of 810 nm and 660 nm lights in the brain metabolic activity of male and female rats was compared. PBM, with a wavelength of 810 nm and a combination of 810 nm and 660 nm, was applied for 5 days on the prefrontal cortex. Then, brain metabolic activity in the prefrontal area, hippocampus, retrosplenial, and parietal cortex was explored. Sex differences were found in cortical and subcortical regions, indicating higher male brain oxidative metabolism, regardless of treatment. CCO activity in the cingulate and prelimbic area, dentate gyrus, retrosplenial and parietal cortex was enhanced in both treatments (810 + 660 nm and 810 nm). Moreover, using the combination of waves, CCO increased in the infralimbic area, and in CA1 and CA3 of the hippocampus. Thus, employment of a single NIR treatment or a combination of red to NIR treatment led to slight differences in CCO activity across the limbic system, suggesting that a combination of lights of the spectrum may be relevant.

COX19 Is a New Target of MACC1 and Promotes Colorectal Cancer Progression by Regulating Copper Transport in Mitochondria

BackgroundRecent studies have demonstrated that copper (Cu) plays an important role in the progression of tumor diseases. Metastasis associated with colon cancer protein 1 (MACC1) promotes the transcription and expression of various tumor-related genes. Cytochrome c oxidase (COX) 19, present in the cytoplasm and intermembrane space of mitochondria, may transport Cu within the mitochondria. However, the mechanism through which MACC1 regulates the Cu homeostasis mediated by COX19 remains unclear. ObjectivesThe aim of this study was to elucidate the mechanism through which MACC1 initiates the transcription and expression of COX19, and promotes malignant behavior in tumor cells. MethodsImmunohistochemistry, western blotting, and real-time polymerase chain reaction (PCR) analyses were conducted to analyze the expression of MACC1 and COX19 proteins and genes in tumor and normal tissues. RNA-chromatin immunoprecipitation was used to detect the transcriptional initiation of COX19 by MACC1. The effects of MACC1 and COX19 on mitochondrial activity were determined using an ATP assay kit and Cytochrome c Oxidase Assay Kit. A Cell Counting Kit-8 kit was used to detect the effect of high-dose Cu or overexpression of MACC1 and COX19 on tumor cell proliferation. A xenograft mouse model was used to analyze the effect of the COX19 overexpression on the malignant behavior of the tumors. ResultsCu enhanced the proliferation, invasion, and migration and inhibited apoptosis of SW480 cells. MACC1 was highly expressed in colorectal cancer tissues and activated the expression of COX19 by binding to its promoter region of COX19. The overexpression of COX19 increased mitochondrial Cu content and enhanced the activity of mitochondrial COX and ATP content, and inhibited apoptosis, promoted tumor growth of mice. ConclusionsOur results indicate that COX19 functions as a target gene of MACC1 and regulates mitochondrial activity and promotes the progression of colorectal cancer. MACC1/COX19 may provide a novel therapeutic target for colorectal cancer.

Unveiling the molecular identity of the diminutive cyprinid, Horadandia brittani (Teleostei: Cyprinidae), a species endemic to Southern India.

Horadandia brittani is a small cyprinid fish species initially discovered in the coastal floodplains of southern India. For almost 50 years, the genus Horadandia was monotypic with a single species confined to Sri Lanka. In 1992, a new species H. brittani was described from south-western India. Despite being described as a separate species, H. brittani was later considered a synonym of H. atukorali, but in 2013, researchers recognized it as a distinct species based on morphological differences. Despite this clarification, there was still a need to validate the identity of H. brittani and determine its evolutionary relationship with its closely related species using DNA sequences. To address the uncertainties surrounding the identity of H. brittani, the present study utilized molecular techniques to generate DNA sequences. Sample collection involved obtaining specimens of H. brittani from their natural habitats. Subsequently, DNA was extracted from the collected samples, and the mitochondrial cytochrome C oxidase (COI) gene was amplified using appropriate methods. The analysis of DNA sequences obtained from the COI gene revealed significant genetic distinctions between H. brittani and H. atukorali. The genetic distance values between these two species ranged from 3.21 to 3.63%, clearly indicating that these two species are genetically separate entities. The study successfully established the phylogenetic relationships between H. brittani and H. atukorali based on the COI gene sequences, further confirming the validity of H. brittani as a distinct and separate species. The findings of this study conclusively demonstrate that H. brittani is a valid and separate species, distinct from H. atukorali. The genetic analysis based on mitochondrial COI gene sequences provided strong evidence for the differentiation between these two species. The molecular data generated in this research can be used to identify H. brittani quickly and accurately in the future.

Immunotoxic effects of exposure to the antifouling copper(I) biocide on target and nontarget bivalve species: a comparative in vitro study between Mytilus galloprovincialis and Ruditapes philippinarum.

Edible bivalves constitute an important bioresource from an economic point of view, and studies on their immune responses to environmental pollutants are crucial for both the preservation of biodiversity and economic reasons. The worldwide diffusion of copper(I)-based antifouling paints has increased copper leaching into coastal environments and its potential impact on both target and nontarget organisms. In this study, immunotoxicity assays were carried out with short-term (60min) cultures of hemocytes from the bivalves Mytilus galloprovincialis-a mussel dominant in the macrofouling community-and Ruditapes philippinarum-a clam dominant in the soft-sediment community-exposed to CuCl to compare the toxic effects on their immune responses. The LC50 values were similar, 40μM (3.94mgL-1) for the mussel and 44μM (4.33mgL-1) for the clam. In both species, apoptosis occurred after exposure to 1µM (98.9μgL-1) CuCl, the concentration able to significantly increase the intracellular Ca2+ content. Biomarkers of cell morphology and motility revealed microfilament disruption, a significant decrease in yeast phagocytosis and lysosome hydrolase (β-glucuronidase) inhibition beginning from 0.5µM (49.5μgL-1) CuCl in both the mussel and clam. The same concentration of CuCl affected biomarkers of oxidative stress, as a significant decrease in reduced glutathione content in the cytoplasm and inhibition of mitochondrial cytochrome-c oxidase (COX) were detected in both species. Comparison of the biomarkers showed that clam is more sensitive than the mussel regarding alterations to the lysosomal membrane and reactive oxygen species (ROS) production, which supports the potential harmful effects of antifouling biocides on the survival of nontarget pivotal species in the coastal community.

Local-Scale DNA Barcoding of Afrotropical Hoverflies (Diptera: Syrphidae): A Case Study of the Eastern Free State of South Africa.

The Afrotropical hoverflies remain an understudied group of hoverflies. One of the reasons for the lack of studies on this group resides in the difficulties to delimit the species using the available identification keys. DNA barcoding has been found useful in such cases of taxonomical uncertainty. Here, we present a molecular study of hoverfly species from the eastern Free State of South Africa using the mitochondrial cytochrome-c oxidase subunit I gene (COI). The identification of 78 specimens was achieved through three analytical approaches: genetic distances analysis, species delimitation models and phylogenetic reconstructions. In this study, 15 nominal species from nine genera were recorded. Of these species, five had not been previously reported to occur in South Africa, namely, Betasyrphus inflaticornis Bezzi, 1915, Mesembrius strigilatus Bezzi, 1912, Eristalinus tabanoides Jaennicke, 1876, Eristalinus vicarians Bezzi, 1915 and Eristalinus fuscicornis Karsch, 1887. Intra- and interspecific variations were found and were congruent between neighbour-joining and maximum likelihood analyses, except for the genus Allograpta Osten Sacken, 1875, where identification seemed problematic, with a relatively high (1.56%) intraspecific LogDet distance observed in Allograpta nasuta Macquart, 1842. Within the 78 specimens analysed, the assembled species by automatic partitioning (ASAP) estimated the presence of 14-17 species, while the Poisson tree processes based on the MPTP and SPTP models estimated 15 and 16 species. The three models showed similar results (10 species) for the Eristalinae subfamily, while for the Syrphinae subfamily, 5 and 6 species were suggested through MPTP and SPTP, respectively. Our results highlight the necessity of using different species delimitation models in DNA barcoding for species diagnoses.

First identification of Tyrophagus curvipenis (Acari: Acaridae) and pathogen detection in Apis mellifera colonies in the Republic of Korea

Mites of the genus Tyrophagus (Acari: Acaridae) are among the most widely distributed mites. The species in this genus cause damage to stored products and crops, and pose a threat to human health. However, the influence of Tyrophagus spp. in apiculture remains unknown. In 2022, a study focusing on the identification of Tyrophagus species within five apiaries was conducted in Chungcheongnam Province, Republic of Korea. Its specific objective was to investigate the presence of Tyrophagus mites in response to the reported high mortality of honey bee colonies in this area. Morphological identification and phylogenetic analysis using the mitochondrial gene cytochrome-c oxidase subunit 1 (CO1) confirmed for the first time the presence of the mite species Tyrophagus curvipenis in a honey bee colony in the Republic of Korea. Two honey bee pathogens were detected in the mite, a viral pathogen (deformed wing virus, DWV) and a protozoal pathogen (Trypanosoma spp.). The presence of the two honey bee pathogens in the mite suggests that this mite could contribute to the spread of related honey bee diseases. However, the direct influence of the mite T. curvipenis on honey bee health remains unknown and should be further investigated.

Alleviative effects of pinostrobin against cadmium-induced renal toxicity in rats by reducing oxidative stress, apoptosis, inflammation, and mitochondrial dysfunction.

Cadmium (Cd) is a highly toxic heavy metal that can be found everywhere in the environment and can have harmful effects on both human and animal health. Pinostrobin (PSB) is a bioactive natural flavonoid isolated from Boesenbergia rotunda with several pharmacological properties, such as antiinflammatory, anticancer, antioxidant, and antiviral. This investigation was intended to assess the therapeutic potential of PSB against Cd-induced kidney damage in rats. In total, 48 Sprague Dawley rats were divided into four groups: a control, a Cd (5 mg/kg), a Cd + PSB group (5 mg/kg Cd and 10 mg/kg PSB), and a PSB group (10 mg/kg) that received supplementation for 30 days. Exposure to Cd led to a decrease in the activities of catalase (CAT), glutathione reductase (GSR), superoxide dismutase (SOD), and glutathione peroxidase (GSH-PX), whereas levels of reactive oxygen species (ROS) and malondialdehyde (MDA) increased. Cd exposure also caused a substantial increase in urea, kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), and creatinine levels. Moreover, a noticeable decline was noticed in creatinine clearance. Moreover, Cd exposure considerably increased the levels of inflammatory indices, including interleukin-1b (IL-1b), tumor necrosis factor-a (TNF-a), interleukin-6 (IL-6), nuclear factor kappa-B (NF-kB), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) activity. Cd treatment decreased the expression of the antiapoptotic markers (Bcl-2) while increasing the expression of apoptotic markers (Bax and Caspase-3). Furthermore, Cd treatment substantially reduced the TCA cycle enzyme activity, such as alpha-ketoglutarate dehydrogenase, succinate dehydrogenase, malate dehydrogenase, and isocitrate dehydrogenase. Moreover, mitochondrial electron transport chain enzymes, succinatedehydrogenase, NADH dehydrogenase, cytochrome c-oxidase, and coenzyme Q-cytochrome reductase activities were also decreased following Cd exposure. PSB administration substantially reduced the mitochondrial membrane potential while inducing significant histological damage. However, PSB treatment significantly reduced Cd-mediated renal damage in rats. Thus, the present investigation discovered that PSB has ameliorative potential against Cd-induced renal dysfunction in rats.

Genetic diversity and phylogenetic analysis of mayfly Caenis (Insecta: Ephemeroptera) using Cytochrome C Oxidase I (COI) and 12s rRNA genes from Thailand

Abstract. Prakrongrak N, Boonsoong B, Monthatong M. 2023. Genetic diversity and phylogenetic analysis of mayfly Caenis (Insecta: Ephemeroptera) using Cytochrome C Oxidase I (COI) and 12s rRNA genes from Thailand. Biodiversitas 24: 1989-1997. Mayflies in genus Caenisis one of the top fifth species richnessbelonged to Family Caenidae. The present study aimed to use the partial mitochondrial Cytochrome COxidase subunit I (COI) and 12s rRNA nucleotide sequences for molecular species identification, diversity and phylogenetic relationships of mayflies in genus Caenis Stephens, 1835 species from Thailand. From a total of 37 specimens, thirteen nymphs were morphologically identified into five species: Caenis nasuta Malzacher, C. Picea Kimmins, C. ulmeriana Malzacher, C. cornigera Kang and Yang and C. longiforcipata Malzacher. The other 24 samples were Caenis sp.1 to sp.5. Partial COI sequences of all samples were compared with BOLD and GenBank for species identification. However, the result showed only genus-level identification as Caenis with greater than 80% similarity. For species delimitation, interspecific genetic distance among these species ranged from 14.4 to 26.6% (COI) and from 7.36 to 22.4% (12s rRNA). Intraspecific divergence levels were 0.0% to 2.35%. ABGD analysis of both genes divided data into 10 groups corresponding to 10 morphospecies of Caenis. The phylogenetic relationships of Caenis, COI and 12s rRNA genes also classified each species to well supported clusters. In addition, we report C. cornigera from Thailand for the first time. The COI and 12s rRNA phylogenetic trees indicate a close relationship between C. cornigera and C. longiforcipata, which is supported by their similar morphology.

DNA Barcoding of Argyrops filamentosus (Perciformes: Sparidae) Based on Mitochondrial COI Gene and Histopathological Evaluation of Gills Infected by Monogeneans

Background: Sparidae is a fish family that belongs to the order Perciformes and is commonly known as sea breams and porgies. Many species are included in this family and divided into 71 genera that could be barcoded using mitochondrial DNA genes. These fish are vulnerable to different parasitic taxa that affect fish status. The present study is aimed to confirm the molecular status of Argyrops filamentosus fish via the mitochondrial cytochrome c oxidase (COI) gene and to study the pathological changes of gills infested by monogenean parasites. Methods: Thirty Argyrops filamentosus fish were collected from Jeddah (Saudi Arabia) and identified molecularly via the mtCOI gene. Also, gills were isolated and examined microscopically for presence of monogeneans. Histopathological impacts of monogeneans on fish gills were studied in comparison to the gills of non-infected fish. Result: The DNA of fish species was barcoded and showed highly stringent criteria with the previously Argyrops filamentosus sequence data. The obtained host DNA sequences were deposited in NCBI database under accession number OP975758.1. Examination of the investigated fish gills revealed the presence of three monogenean species Protolamellodiscus senilobatus Kritsky, Jiménez-Ruiz and Sey, 2000, Acleotrema maculatus Morsy, El-Fayoumi and Fahmy (2014) and Haliotrema susanae Soo, 2019. Monogenean parasites penetrated deeply with their haptor to the gill lamella and caused damage and degeneration of epithelial cells leading to the formation of a cup-shaped depression. Therefore, the mtDNA gene has the ability for host identification and heavy monogeneans infections lead to severe damage to fish gills.

Latitudinal shift of the associated hosts inSagamiscintilla thalassemicola(Galeommatoidea: Galeommatidae), a rare ectosymbiotic bivalve that lives on the proboscis of echiuran worms

AbstractSagamiscintilla thalassemicola(Bivalvia: Galeommatoidea: Galeommatidae) is a rare ectocommensal bivalve that lives on the proboscis of echiuran worms,Anelassorhynchusspp. (Annelida: Thalassematidae: Thalassematinae: Thalassematini), and has been known only from the temperate zones of Japan. In this study, we foundS. thalassemicolaon the proboscis of the large echiuranOchetostomasp. (Thalassematidae: Thalassematinae: Thalassematini) on intertidal flats of three islands of the Ryukyu Archipelago, southern Japan. These are the first records ofS. thalassemicolaon non-Anelassorhynchushosts and also from the subtropical regions. Additionally, we also collectedS. thalassemicolafrom an intertidal flat of Kushimoto, Wakayama, Kii Peninsula, Japan, which is an update of the easternmost record of this species. The genetic differences in the mitochondrial cytochromecoxidase subunit I and nuclear internal transcribed spacer 2 genes amongS. thalassemicola, including those withOchetostomasp. from the subtropical region and withAnelassorhynchusspp. from the temperate region, can be considered within the intraspecific variation. These suggest thatS. thalassemicolauses different echiuran hosts in the temperate and subtropical regions, respectively.

Lithium boosts neuronal bioenergetics in Alzheimer’s disease

AbstractBackgroundAlzheimer's disease (AD) is characterized by the accumulations of amyloid beta and neurofibrillary tangles in brain tissue; however, AD is multifactorial and different etiopathogenic mechanisms involves that can affect mitochondrial function that are associated with AD. In the current study, we investigated the effect of lithium on mitochondrial function in AD.MethodNeuronal cells were isolated separately from hippocampal of brain tissue of control mice (C57BL/6) and 3xTg model of AD. Mitochondrial oxygen consumption rate (OCR), mitochondrial Cytochrome C Oxidase (COX) activity, and total ATP activity were measured in control vs. AD neurons after one day and seven days dose‐dependent treatment with lithium.ResultIn the present study, short and long term lithium treatment significantly increased (p<0.05) mitochondrial OCR, COX, and total ATP level in 3xTg neurons. However, lithium had no effect on energy metabolism in control neurons. Together, these data indicate that lithium improves mitochondrial function under pathological states.ConclusionOverall, these results have important implications for the treatment of disorders in which brain energy regulation are compromised, including AD. Particularly, our results highlight a role for lithium in regulating bioenergetics in early stage AD and suggest that neuronal cells may be a crucial therapeutic target for preventing AD.

Empagliflozin suppresses urinary mitochondrial DNA copy numbers and interleukin-1β in type 2 diabetes patients

Sodium-glucose co-transporter 2 (SGLT2) inhibitors improve cardiovascular and renal outcomes in type 2 diabetes mellitus (T2DM) patients. However, the mechanisms by which SGLT2 inhibitors improve the clinical outcomes remain elusive. We evaluated whether empagliflozin, an SGLT2 inhibitor, ameliorates mitochondrial dysfunction and inflammatory milieu of the kidneys in T2DM patients. We prospectively measured copy numbers of urinary and serum mitochondrial DNA (mtDNA) nicotinamide adenine dinucleotide dehydrogenase subunit-1 (mtND-1) and cytochrome-c oxidase 3 (mtCOX-3) and urinary interleukin-1β (IL-1β) in healthy volunteers (n = 22), in SGLT2 inhibitor-naïve T2DM patients (n = 21) at baseline, and in T2DM patients after 3 months of treatment with empagliflozin (10 mg, n = 17 or 25 mg, n = 4). Both urinary mtDNA copy numbers and IL-1β levels were higher in the T2DM group than in healthy volunteers. Baseline copy numbers of serum mtCOX-3 in the T2DM group were lower than those in healthy volunteers. Empagliflozin induced marked reduction in both urinary and serum mtND-1 and mtCOX-3 copy numbers, as well as in urinary IL-1β. Empagliflozin could attenuate mitochondrial damage and inhibit inflammatory response in T2DM patients. This would explain the beneficial effects of SGLT2 inhibitors on cardiovascular and renal outcomes.

A huge undescribed diversity of the subgenus Hystricochaetonotus (Gastrotricha, Chaetonotidae, Chaetonotus) in Central Europe

The subgenus Hystricochaetonotus Schwank, 1990 is one of the most species-rich subgenera of Chaetonotus Ehrenberg, 1830. It has a worldwide distribution and encompasses 37 species predominantly living in the benthos and periphyton of limnetic habitats. We have discovered further nine new species in running and stagnant waters in Slovakia (Central Europe): Ch. (H.) arcanus sp. nov., Ch. (H.) avarus sp. nov., Ch. (H.) gulosus sp. nov., Ch. (H.) iratus sp. nov., Ch. (H.) luxus sp. nov., Ch. (H.) mirabilis sp. nov., Ch. (H.) optabilis sp. nov., Ch. (H.) slavicus sp. nov., and Ch. (H.) superbus sp. nov. Their morphology was studied using differential interference contrast microscopy and subsequent morphometric analyses were carried out. In addition, the primary and secondary structures of their 18S, ITS2, and 28S rRNA molecules as well as their barcoding mitochondrial gene encoding for cytochrome c oxidase (COI) were analyzed. Species boundaries were tested also using the compensatory base change analysis. The new species could be well separated both morphologically and molecularly. The present barcoding analyses revealed that the nuclear ITS2 sequences represent a powerful DNA barcode in addition to the mitochondrial COI gene. According to the multi-gene phylogenetic analyses, the lineage leading to the last common ancestor of the ‘Hystricochaetonotus’ clade is the longest internal branch within the family Chaetonotidae Gosse, 1864. Since members of the subgenus Hystricochaetonotus are morphologically highly heterogeneous, parallel evolution of Chaetonotus-like and/or Hystricochaetonotus-like characters of scales and spines occurred during its radiation.

Endurance Training Increases the Running Performance of Untrained Men without Changing the Mitochondrial Volume Density in the Gastrocnemius Muscle.

The activity and quantity of mitochondrial proteins and the mitochondrial volume density (MitoVD) are higher in trained muscles; however, the underlying mechanisms remain unclear. Our goal was to determine if 20 weeks’ endurance training simultaneously increases running performance, the amount and activity of mitochondrial proteins, and MitoVD in the gastrocnemius muscle in humans. Eight healthy, untrained young men completed a 20-week moderate-intensity running training program. The training increased the mean speed of a 1500 m run by 14.0% (p = 0.008) and the running speed at 85% of maximal heart rate by 9.6% (p = 0.008). In the gastrocnemius muscle, training significantly increased mitochondrial dynamics markers, i.e., peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) by 23%, mitochondrial transcription factor A (TFAM) by 29%, optic artrophy-1 (OPA1) by 31% and mitochondrial fission factor (MFF) by 44%, and voltage-dependent anion channel 1 (VDAC1) by 30%. Furthermore, training increased the amount and maximal activity of citrate synthase (CS) by 10% and 65%, respectively, and the amount and maximal activity of cytochrome c oxidase (COX) by 57% and 42%, respectively, but had no effect on the total MitoVD in the gastrocnemius muscle. We concluded that not MitoVD per se, but mitochondrial COX activity (reflecting oxidative phosphorylation activity), should be regarded as a biomarker of muscle adaptation to endurance training in beginner runners.

Molecular Identification and Phylogenetic Analysis of Some Common Beetles (Coleoptera) of Jammu Region, India Using DNA Barcoding

Coleoptera is a highly diverse and taxonomically important order of Class Insecta. DNA Barcoding hasproven its effectiveness as an accurate molecular taxonomy tool in differentiating various species belongingto same genus. We carried out a pilot study for testing the effectiveness of mitochondrial cytochrome Coxidase sub unit 1 based DNA Barcoding for common species of beetles from Jammu region of UT of J&K.Successful generation of DNA barcodes of 04 species was achieved and the sequences were submitted toGenBank. The phylogenetic analysis was performed by using Neighbor-Joining method and Kimura-2-Parameter with 1000 bootstrap supports, gap opening penalty of 15.00 and a gap extension penalty of 6.66in both pair-wise as well as multiple alignments.

Thymidine Kinase 2 and Mitochondrial Protein COX I in the Cerebellum of Patients with Spinocerebellar Ataxia Type 31 Caused by Penta-nucleotide Repeats (TTCCA)n

Spinocerebellar ataxia type 31 (SCA31), an autosomal-dominant neurodegenerative disorder characterized by progressive cerebellar ataxia with Purkinje cell degeneration, is caused by a heterozygous 2.5–3.8 kilobase penta-nucleotide repeat of (TTCCA)n in intron 11 of the thymidine kinase 2 (TK2) gene. TK2 is an essential mitochondrial pyrimidine-deoxyribonucleoside kinase. Bi-allelic loss-of-function mutations of TK2 lead to mitochondrial DNA depletion syndrome (MDS) in humans through severe (~ 70%) reduction of mitochondrial electron-transport-chain activity, and tk2 knockout mice show Purkinje cell degeneration and ataxia through severe mitochondrial cytochrome-c oxidase subunit I (COX I) protein reduction. To clarify whether TK2 function is altered in SCA31, we investigated TK2 and COX I expression in human postmortem SCA31 cerebellum. We confirmed that canonical TK2 mRNA is transcribed from exons far upstream of the repeat site, and demonstrated that an extended version of TK2 mRNA (“TK2-EXT”), transcribed from exons spanning the repeat site, is expressed in human cerebellum. While canonical TK2 was conserved among vertebrates, TK2-EXT was specific to primates. Reverse transcription-PCR demonstrated that both TK2 mRNAs were preserved in SCA31 cerebella compared with control cerebella. The TK2 proteins, assessed with three different antibodies including our original polyclonal antibody against TK2-EXT, were detected as ~ 26 kilodalton proteins on western blot; their levels were similar in SCA31 and control cerebella. COX I protein level was preserved in SCA31 compared to nuclear DNA-encoded protein. We conclude that the expression and function of TK2 are preserved in SCA31, suggesting a mechanism distinct from that of MDS.

Multiple lines of evidence confirm that the critically endangered Blue-crowned Laughingthrush (Garrulax courtoisi) is an independent species

The taxonomy of the Blue-crowned Laughingthrush (Garrulax courtoisi) and its relationship with the Yellow-throated Laughingthrush (G. galbanus) and G. c. simaoensis, a range-restricted subspecies in China, has not been fully elucidated. So the taxonomic status and system evolution of the three taxa G.courtoisi, G. galbanus and G. c. simaoensis need to be reclarified. Two gene sequences myoglobin (MYO) and the mitochondrial cytochrome coxidase subunit I (COI) were combined to investigate the phylogenetic relationships among courtoisi, simaoensis and galbanus, genetic data, combining with morphological, ecological and acoustic data were used to comb out the classification status and divergence level of the three taxa. Significant genetic and morphological differentiations (body size and plumage coloration) were detected between courtoisi and galbanus. However, no notable and reliable differences between the courtoisi and simaoensis were detected. The courtoisi, simaoensis and galbanus are clearly isolated in geographical distribution as a result of differing altitudes, climate conditions and habitats. The courtoisi has characteristic preference for nest location compared with galbanus. In addition, the results of song analysis also indicated that there are differences in maximum frequency between courtoisi and galbanus. G. courtoisi was confirmed to be an independent species based on genetic, morphological, geographical, ecological and vocal characteristics, and the validity of simaoensis as a subspecies still need more evidence. This study further confirmed the high conservation value of Blue-crowned Laughingthrush. In addition, due to the genetic differences between Simao and Wuyuan populations, this should be fully considered in future protection strategies.

Coping with extremes: High-altitude sparrows enhance metabolic and thermogenic capacities in the pectoralis muscle and suppress in the liver relative to their lowland counterparts

Animals living at high altitudes are challenged by the extreme environmental conditions of cold temperature and hypobaric hypoxia. It is not well understood how high-altitude birds enhance the capacity of metabolic thermogenesis and allocate metabolic capacity in different organs to maximize survival in extreme conditions of a cold winter. The Qinghai-Tibet Plateau (QTP) is the largest and highest plateau globally, offering a natural laboratory for investigating coping mechanisms of organisms inhabiting extreme environments. To understand the adaptive strategies in the morphology and physiology of small songbirds on the QTP, we compared plasma triiodothyronine (T3), pectoralis muscle mitochondrial cytochrome c oxidase (COX) and state IV capacities, the expression of peroxisome proliferator-activated receptor γ coactivator α (PGC-1α), adenine nucleotide translocase (ANT), uncoupling protein (UCP), and adenosine monophosphate‐dependent kinase (AMPK) α1 mRNA in the pectoralis and liver of Eurasian tree sparrows (Passer montanus) from high-altitude (3,230 m), medium-altitude (1400 m), and low-altitude (80 m) regions. Our results showed that high-altitude sparrows had greater body masses, longer wings and tarsometatarsi, but comparable bill lengths relative to medium- and low-altitude individuals. High-altitude sparrows had higher plasma T3 levels and pectoralis muscle mitochondrial COX capacities than their lowland counterparts. They also upregulated the pectoralis muscle mRNA expression of UCP, PGC-1α, and ANT proteins relative to low-altitude sparrows. Unlike pectoralis, high-altitude sparrows significantly down-regulated hepatic AMPKα1 and ANT protein expression as compared with their lowland counterparts. Our results contribute to understanding the morphological, biochemical, and molecular adaptations in free-living birds to cope with the cold seasons in the extreme environment of the QTP.