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Although hair loss is not a horrible disease, it sometimes reduces the patients' quality of life (QOL) and increases their mental stress. Currently, there is no effective treatment for hair loss. It is known that honeybee propolis has various biological activities, including stimulating the proliferation of hair matrix keratinocytes. However, little is known with the hair promoting activity of stingless bee propolis. Hence, this study investigates the hair growth-promoting activity of Philippines stingless bee propolis extract and the underlying a molecular mechanism of promoting hair growth. For the evaluation of hair growth stimulating activity, 99.5% ethanolic extract of Philippines stingless bee propolis is examined using the simple shaving model in C57BL/6N mice. Melaninization of dorsal skin and histological analysis of hair follicles (HFs) revealed that propolis promotes hair growth by stimulating HFs development. The expression of mRNA (Wnt3a, Ctnnb1/β-catenin, Lef1, and Bmp2) and protein (WNT3A and β-catenin) of selected Wnt/β-catenin associated genes explains Philippines stingless bee propolis promoting HFs development by activating Wnt/β-catenin signaling pathway. These results suggest that the treatment of propolis strongly promotes hair growth by stimulating the development of HFs via activation of Wnt/β-catenin signaling pathway. This further indicates the potential of Philippines stingless bee propolis as a novel promising agricultural product for hair growth.

Recombinant expression system was established for rainbow trout myoglobin (Mb) considering its unique primary structure of having one unusual deletion and two cysteine residues in contrast to the other fish Mbs. The obtained recombinant Mb without His-tag showed non-cooperative thermal denaturation profile. The presence of free cysteine residue(s) in rainbow trout Mb was demonstrated by reacting with a sulfhydryl agent, 4, 4´-dithiodipyridine, which ultimately resulted in the oxidation of Mb with characteristic changes in visible absorption spectra. Besides, the recombinant Mb displayed steady peroxidase reactivity indicating in vivo roles of Mb as a reactive oxygen species scavenger. The findings of the present study indicate that the solitary rainbow trout Mb, which ultimately manifest typical secondary structure pattern and corroborate characteristic functionality, can be over expressed in recombinant system devoid of fusion tag.

Although myoglobin (Mb) has been considered to be one of the well-characterized proteins, screening of post-genomic era databases revealed the lack of adequate information on teleost Mbs. The present study was aimed to investigate stability and functional features of Mbs from three teleosts of the same family. To unfold how primary structure influences the stability and function of proteins, Mbs were purified from the dark muscles of three carangids, namely, yellowtail, greater amberjack, and silver trevally. Thermostabilities measured by circular dichroism (CD) spectrometry revealed species-specific thermal denaturation pattern, i.e., silver trevally > yellowtail > greater amberjack Mbs. On the other hand, autoxidation rate constants of the ferrous forms of those three carangid Mbs showed positive correlation between the ferrous state of the heme iron and rising temperature. The order of autoxidation rate was in the order of greater amberjack > yellowtail > silver trevally Mbs. The finding of the present study denotes that the thermal stability is not necessarily correlated with the functional stability of carangid Mbs even though their primary structures shared high homology (84–94%).

Surimi gel is a commonly found gelled product in Japan. Disintegration of the surimi gel is mainly caused by proteolytic degradation of the myosin heavy chain (MHC) under an inappropriate heating process. Many studies have reported the decrease in MHC in the disintegrated surimi gel but the mechanistic details of this degradation remain unclear. This study employed peptidomic analysis of disintegrated surimi gels from deep-sea bonefish Pterothrissus gissu to reveal the MHC cleavage causing gel disintegration. More peptides derived from an MHC rod were found in the disintegrated P. gissu surimi gels than in the integrated gel. Most MHC peptides were derived from the Src homology 3 domain or near the skip residues. The results of the terminome analysis suggest that the catalytic type of the proteases is responsible for light meromyosin cleavage activated at ∼35 °C. These results showed the temperature-dependent cleavage of the MHC rod, causing disintegration of the P. gissu surimi gel.

The protective property of propolis across a wide spectrum of diseases has long been realized, yet the anti-tumor efficacy of this bioactive substance from Philippine stingless bees has remained poorly understood. Here, we showed the tumor-suppressing potential of crude ethanolic extract of Philippine stingless bee propolis (EEP) in in vitro models of gastric cancer highlighting the first indication of remarkable subtype specificity towards differentiated-type human gastric cancer cell lines but not the diffuse-type. Mechanistically, this involved the profound modulation of several cell cycle related gene transcripts, which correlated with the prominent cell cycle arrest at the G0/G1 phase. To reinforce our data, a unique differentiated-type gastric cancer model, A4gnt KO mice, together with age-matched 60 week-old C57BL/6 J mice were randomly assigned to treatment groups receiving distilled water or EEP for 30 consecutive days. EEP treatment induced significant regression of gross and histological lesions of gastric pyloric tumors that consistently corresponded with specific transcriptional regulation of cell cycle components. Also, the considerable p21 protein expression coupled with a marked reduction in rapidly dividing BrdU-labeled S-phase cells unequivocally supported our observation. Altogether, these findings support the role of Philippine stingless bee propolis as a promising adjunct treatment option in differentiated-type gastric cancer.

Recent studies have suggested that thaw-aging can improve sensory attributes of freeze-thawed meat. Acceleration of proteolysis is expected to promote tenderisation and improve taste; however, the details of protein degradation, including substrate proteins and cleavage sites, remain unclear. Here, we report a time course overview of the peptidome of beef short plates during thaw-aging. The accelerated degradation of key proteins for meat tenderisation, such as troponin T and desmin, was confirmed. Additionally, 11 cleavage sites in troponin T related to taste-active peptide generation were identified. Terminome analysis showed that the contribution of each protease varies depending on the substrate proteins and the thaw-aging period. Based on our results; proteases, not only calpains, but also others contributed to the degradation of myofibrillar proteins. The techniques employed indicate that meat proteolysis during thaw-aging is not constant but dynamic.

Recombinant expression system was established for rainbow trout myoglobin (Mb) considering its unique primary structure of having one unusual deletion and two cysteine residues in contrast to the other fish Mbs. The obtained recombinant Mb without His-tag showed non-cooperative thermal denaturation profile. The presence of free cysteine residue(s) in rainbow trout Mb was demonstrated by reacting with a sulfhydryl agent, 4, 4´-dithiodipyridine, which ultimately resulted in the oxidation of Mb with characteristic changes in visible absorption spectra. Besides, the recombinant Mb displayed steady peroxidase reactivity indicating in vivo roles of Mb as a reactive oxygen species scavenger. The findings of the present study indicate that the solitary rainbow trout Mb, which ultimately manifest typical secondary structure pattern and corroborate characteristic functionality, can be over expressed in recombinant system devoid of fusion tag.

© 2021 The Authors., The long-standing paradigm establishing that global production of Omega-3 (n–3) long-chain polyunsaturated fatty acids (LC-PUFA) derived almost exclusively from marine single-cell organisms, was recently challenged by the discovery that multiple invertebrates possess methyl-end (or ωx) desaturases, critical enzymes enabling the biosynthesis of n–3 LC-PUFA. However, the question of whether animals with ωx desaturases have complete n–3 LC-PUFA biosynthetic pathways and hence can contribute to the production of these compounds in marine ecosystems remained unanswered. In the present study, we investigated the complete enzymatic complement involved in the n–3 LC-PUFA biosynthesis in Tigriopus californicus, an intertidal harpacticoid copepod. A total of two ωx desaturases, five front-end desaturases and six fatty acyl elongases were successfully isolated and functionally characterized. The T. californicus ωx desaturases enable the de novo biosynthesis of C18 PUFA such as linoleic and α-linolenic acids, as well as several n–3 LC-PUFA from n–6 substrates. Functions demonstrated in front-end desaturases and fatty acyl elongases unveiled various routes through which T. californicus can biosynthesize the physiologically important arachidonic and eicosapentaenoic acids. Moreover, T. californicus possess a Δ4 desaturase, enabling the biosynthesis of docosahexaenoic acid via the ‘Δ4 pathway’. In conclusion, harpacticoid copepods such as T. californicus have complete n–3 LC-PUFA biosynthetic pathways and such capacity illustrates major roles of these invertebrates in the provision of essential fatty acids to upper trophic levels., This study was partly funded through the project IMPROMEGA of the Ministry of Science, Innovation and Universities, Spanish Government (grant no. RTI2018-095119-B-I00, MCIU/AEI/FEDER, UE). N.K. was supported by the JSPS KAKENHI grant no. JP19K15908.

Obesity is a global public health problem and a risk factor for several metabolic disorders as well as cancer. In this study, we investigated the effects of L-fucose on lipid metabolism through chronic and acute in vivo experiments in mice. In the chronic test, mice were fed a high-calorie diet (HCD) containing 0.0001%, 0.001%, 0.01%, and 0.1% L-fucose for one month. The L-fucose supplementation inhibited body weight and visceral fat mass gain in HCD-fed mice. The results of the acute test showed that L-fucose increased the ratio of serum high molecular weight adiponectin and enhanced glucose and lipid catabolism. Furthermore, L-fucose also decreased the expression of adipogenic genes (peroxisome proliferator-activated receptor &gamma, and cluster of differentiation 36). In conclusion, this study provides a new approach to combat obesity and the related diseases.

Surimi gel is a commonly found gelled product in Japan. Disintegration of the surimi gel is mainly caused by proteolytic degradation of the myosin heavy chain (MHC) under an inappropriate heating process. Many studies have reported the decrease in MHC in the disintegrated surimi gel but the mechanistic details of this degradation remain unclear. This study employed peptidomic analysis of disintegrated surimi gels from deep-sea bonefish

Magnetic resonance technologies, such as nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI), are powerful tools used in various fields of science. In this review, we provide a broad overview of the application of magnetic resonance technologies in aquatic biology following brief descriptions of their principles and characteristics. The topics covered include in vitro and in vivo NMR spectroscopy, NMR metabolomics, MRI, and their application to seafood science. Special attention is paid to in vivo NMR spectroscopy and metabolic tracing using a stable isotope, 13C, which provide safe and effective means of exploring the metabolic diversity of aquatic organisms.

Myoglobin (Mb) is one of the most intensively studied intracellular respiratory muscle proteins. Since the discovery of the fascinating fact that Mb is not confined only to oxidative muscle tissues but also is co-localized in different non-muscle tissues of cyprinids, hypoxia tolerant cyprinids have been established as the model teleost. Mb both at mRNA and protein levels have been reported in this study for the first time from a number of muscle and non-muscle tissues of rainbow trout Oncorhynchus mykiss, a hypoxia intolerant species. Mb transcript levels were high in the heart and slow skeletal muscle, and were comparatively high in the gonad and gill among the non-muscle tissues. Western-blotting by using anti-rainbow trout Mb peptide rabbit antibody detected Mb protein in the muscles and several non-muscle tissues. By both RNA in situ hybridization and immunofluorescence, Mb was localized in the cardiomyocytes and oxidative muscle fibers. On the other hand, Mb both at mRNA and protein levels was restricted to the lamellar epithelial cells of the gill, epithelial layers of hepato-biliary duct, neurons and endothelial cells of brain, ooplasm of gonad, kidney tubules, endothelial cells, and epithelial layer of intestine. Neuroglobin isoform 1 and 2 mRNAs along with Mb mRNA were localized in the granular layer of cerebellum. Considering the previous data reported for cyprinids, the expression sites of Mb in the muscle and non-muscle tissues of teleost could be universal, where Mb concerted with the other globins might play meaningful physiological roles.

Despite the increasing environmental concern about the emission of ethanol from ethanol-blended fuels, the aquatic toxicity of ethanol has not been well investigated especially at low concentrations. In this study, we aimed to investigate the effects of 0.1% ethanol on life history parameters and population dynamics of the rotifer Brachionus plicatilis by a series of culture experiments. Rotifers exposed to 0.1% ethanol lived about 20% longer and the first egg-bearing individual appeared about 30 min earlier in the ethanol-exposed group than the control group. The lifetime fecundity was approximately 1.3-fold higher in the ethanol-exposed group than the control group, but the difference was not statistically significant. Ethanol exposure also increased survival time under 0.5 mM hydrogen peroxide. Furthermore, in the batch culture experiment, the maximum population density of ethanol-exposed groups was 1.7 times higher than that of control groups. Overall, these life history alterations were similar to those in glycerol-treated rotifers previously reported, suggesting a common mechanistic basis. Identification of the mechanism of ethanol action will enable future evaluation of effects of increased ethanol release on the organisms in the aquatic environment.

Attempts have been made to elucidate the denaturation profiles of tuna myoglobin (Mb) in comparison with horse Mb. Intensive absorbance characterization was carried out for derivatives (deoxy, oxy, met forms) of Mb. The wavelength of the maximum absorbance of tuna Mb was shorter only by 1 nm for deoxy and metMb, while it was 4 nm shorter for the second peak of metMb. Percentage Mb denaturation (PMD) was measured under a combination of pH (5.6, 6.5, 7.4) and temperature (70, 75, 80 °C). Tuna Mb was almost completely denatured even during the initial incubation at 75 and 80 °C at all pHs examined. During the incubation at 70 °C, the PMD values for tuna Mb were 88.5, 52.1, and 67.7% at pH 5.6, 6.5, and 7.4, respectively. The denaturation of tuna Mb proceeded even at 55 °C, but denaturation rates were very slow at pH 6.5. On the other hand, horse Mb was found to be very stable at pH 6.5 and 7.4 at all temperatures examined, except at pH 6.5 and 80 °C. At pH 5.6, the PMD values of horse Mb gradually increased, especially at 75 and 80 °C. These different Mbs showed quite different denaturation profiles.

Determination of the redox state of myoglobin (Mb) gives useful information for evaluating the quality of tuna meat. To attain this purpose, a fast streamlined method has been established basically based on preparative native gel electrophoresis to isolate Mb from the dark muscle of Pacific bluefin tuna. Crude Mb fraction was prepared from dark muscle by ammonium sulfate saturation fractionation and subsequently Mb was purified by preparative native gel electrophoresis under the isoelectric pH of the Mb, resulting in absorption (or trapping) of all the contaminating proteins in the gel. Purified Mb was converted to oxy form with a trace amount of sodium hydrosulfite, and subsequently dialyzed against 50 mM sodium citrate (pH 5.6) or 50 mM sodium phosphate (pH 6.5). The purified tuna Mb was examined for the temperature and pH dependencies of autoxidation using horse Mb as a reference. Tuna Mb was oxidized 2.5–3 times faster than horse Mb irrespective of the pH conditions examined. The highest autoxidation rates both at 0 and 37 °C were observed at pH 5.6. These data were comparable to those obtained for Mbs isolated by conventional chromatographic methods. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13197-018-3068-3) contains supplementary material, which is available to authorized users.

Taurine and hypotaurine are abundantly present in molluskan tissues; however, the pathways for their biosynthesis have not yet been well investigated. In this study, we established a method for simultaneous detection of taurine-related compounds, including taurine, hypotaurine, cysteic acid, cysteine sulfinic acid (CSA), cystathionine, γ-aminobutyric acid, and β-alanine along with 17 free amino acids, using phenylthiocarbamyl derivatization in ammonia-containing solution, followed by injection into reversed-phase high-performance liquid chromatography. Using this method, we analyzed the major tissues (gill, mantle, adductor muscle, foot, and digestive gland) of the hydrothermal-vent-specific mussel Bathymodiolus septemdierum. The gill and digestive gland were suggested to be the major organs for taurine/hypotaurine biosynthesis because taurine and hypotaurine levels tended to be high, and their precursors, i.e., cysteine, cysteic acid, and CSA (only in digestive gland), were detected in these two tissues. Cystathionine was detected at relatively high level in digestive gland and in other tissues at low levels, suggesting its role as storage material for taurine/hypotaurine biosynthesis. Adductor muscle was found to be rich in free amino acids, mainly due to abundance of non-sulfur-containing amino acids.

Cycloartenyl ferulate (CAF) is a major bioactive phytosteryl ferulate purified from rice bran ?- oryzanol. Previously we reported that CAF ameliorates DSS-induced colitis in mice. The present study was undertaken to investigate the effects of CAF on LPS (lipopolysaccharide) stimulated murine RAW 264.7 macrophages. Immunohistochemistry analysis demonstrated that LPS (10ng/mL) treatment exhibited nuclear translocation of NF-?B-p65 in RAW macrophages, which was markedly inhibited CAF (30?M). LPS (10ng/mL) stimulation for 1-4 hours significantly upregulated iNOS and COX-2 mRNA in RAW 264.7 macrophages, but COX-2 mRNA was faster than that of iNOS mRNA. Macrophages pretreated with CAF greatly inhibited the LPS stimulated iNOS mRNA in a dose dependent manner (1-30?M), but CAF weakly inhibited COX-2 mRNA. Interestingly, CAY 10404 (COX-2 inhibitor) inhibited LPS stimulated iNOS mRNA, but not COX-2. In addition, PGE2 (1?M) upregulated iNOS mRNA but did not show any remarkable effects on NF-?B-p65 nuclear translocation in RAW macrophages. PD98059 (p44/42 MAP kinase inhibitor) inhibited iNOS mRNA, but not COX-2. On the other hand, PD169316 (p38 MAP kinase inhibitor) neither inhibited iNOS mRNA nor COX-2. Our results suggest that iNOS mRNA expression by LPS is mediated via p44/42 MAP kinase pathway in RAW 264.7 macrophages, which depends on the preceding expression of COX-2 expression. CAF downregulates iNOS mRNA via an inhibition of nuclear translocation of NF-?B with different mode of action on COX-2 gene expression.Asian J. Med. Biol. Res. December 2016, 2(4): 523-531

Growth hormone (GH) increases phosphorylation and mRNA levels of hormone-sensitive lipase (HSL) in the livers of some marine teleosts. The hepatic GH-HSL axis appears to play important roles in fasting-induced lipolysis. However, it is not known whether GH exerts similar effects on HSL in fish adipose tissues. Functional differentiation of two fish-specific HSL isoforms (HSL1 and HSL2) also remains unclear. The present study seeks to address two unanswered questions about fish lipolysis using red seabream (Pagrus major): (1) Does GH increase phosphorylation and mRNA levels of HSL in adipose tissue? (2) How do GH and fasting affect mRNA levels of two HSL isoform genes in the liver and adipose tissue? To this end, we first cloned HSL1 and HSL2 cDNAs and investigated their tissue distribution. Transcripts of both HSLs and HSL1 proteins were abundant in the visceral adipose tissue, gonads, and liver, suggesting the important role of HSL in adipose tissue lipolysis. HSL2 transcript levels were 20-65% those of HSL1 except in the skin, and HSL2 proteins were not detected by our in-house antisera. Ex vivo administration of GH increased HSL1 phosphorylation, non-esterified fatty acid (NEFA) release, and levels of HSL1 and HSL2 mRNA in both the liver and visceral adipose tissue. Hepatic HSL2 mRNA was particularly sensitive to GH administration and sometimes exceeded HSL1 mRNA levels with up to 13-fold induction. In contrast, fasting for 4 and 7d increased HSL1 mRNA levels, but had only marginal effects on HSL2 mRNA levels in both adipose tissue or liver. We concluded that GH would increase HSL mRNAs during adipose tissue lipolysis in red seabream; however, GH and fasting result in different induction ratio of two HSL isoform genes, suggesting that other hormone(s) also contributes to fasting-induced lipolysis.

Adipose tissue is a lipid storage organ characterized by the pronounced accumulation of adipocytes. Although adipose tissues are found in various parts of the vertebrate body, it is unclear whether these tissues have a common ancestral origin or have evolved in several phylogenetic lineages by independent adipocyte accumulation events. To gain insight into the evolutionary history of vertebrate adipose tissues, we determined the distribution of adipocytes by oil red O staining in skeletal muscle of 10 teleost species spanning eight orders: Tetraodontiformes, Pleuronectiformes, Spariformes, Salmoniformes, Clupeiformes, Beloniformes, Osmeriformes, and Cypriniformes. Accumulation of adipocytes in the myoseptum was observed in many species, including red seabream, rainbow trout, Pacific herring, Pacific saury, zebrafish and giant danio. We also found some order-, species-, and swimming mode-specific distribution patterns of adipocytes: 1) almost complete absence of intramuscular adipocytes in the order Tetraodontiformes (torafugu and spotted green pufferfish), 2) clear adipocyte accumulation in the inclinator muscles of fin in Japanese flounder, 3) a large intramuscular adipose tissue at the root of the dorsal fin in ayu, and 4) thick lipid layers consisting of subcutaneous adipose tissue and red muscle lipids in pelagic migratory fish (Pacific herring and Pacific saury). Of note, Pacific herring and Pacific saury are phylogenetically distinct species sharing a similar niche and swimming mode, suggesting that their analogous adipocyte/lipid distribution patterns are the consequence of convergent evolution. The potentially heterogeneous origin of adipose tissues has significant implications for the interpretation of their functional diversity.

Cultured fish are often subjected to short-term fasting for a few days prior to transport or slaughter. This intervention reduces waste and oxygen consumption during transport and improves flesh quality, but little is known about how it affects the muscle lipid content. Even less is known for wild-caught fish that are also sometimes fasted before slaughter. To investigate the effects of short-term fasting on muscle lipid content, we performed three fasting experiments using adult, lean juvenile, and fatty juvenile red seabream ( Pagrus major ). In the first experiment using adult specimens (performed at 20 °C), fasting for 10 days caused up to 2.3-, 7.8-, and 3.7-fold increases in muscle mRNA levels of lipoprotein lipase 1 ( LPL1 ), LPL2 , and peroxisome-proliferator-activated receptor gamma ( PPAR γ), respectively (n = 6 each). These genes all participate in lipid accumulation. The second experiment was performed on 5 groups of lean juvenile red seabream [considered as wild-caught fish; 19 °C, n = 5 each except for one group (n = 4)]. Fasting for 5 days significantly increased muscle lipid content (percentage of wet weight) and LPL1 mRNA levels up to 2.2- and 11-fold, respectively. The mRNA levels of LPL2 and PPAR γ could not be determined possibly due to their low expression levels. The lipid amount (mg) in the liver decreased by 88% during fasting, whereas adipose tissue apparently disappeared after fasting for 10 days. These results suggest that lipid mobilization from liver and adipose tissue anticipated the muscular utilization of lipid, resulting in the counterintuitive increase in muscle lipid content during fasting. The third experiment was conducted on 7 groups of fatty juvenile red seabream [considered as cultured fish; 20 °C, n = 5 each except for one group (n = 4)]. Fasting up to 10 days did not increase muscle lipid content or LPL1 mRNA levels. The lipid amount in the liver, but not in the adipose tissue, decreased during the experiment. Fasting for 10 days was not enough to induce active lipid mobilization when fish were well fed prior to fasting. Contrary to our expectations, regression analysis using data from juvenile specimens found a significant inverse relationship between LPL1 mRNA levels and lipid amount in the liver, which might indicate that LPL1 mRNA levels are a reflection of temporal tissue demand for lipids. Overall, these results suggest that short-term fasting for ~ 5 days increases muscle lipid content of wild-caught lean fish possibly by an LPL1-dependent lipid transport mechanism. Statement of relevance We showed that short-term fasting improves flesh quality.

Motile aeromonad septicemia caused by mesophilic strains of Aeromonas hydrophila is a widespread problem in cultured freshwater fish. We announce here the draft genome sequence of the multidrug-resistant A. hydrophila strain Ae25, isolated from a koi carp ( Cyprinus carpio ) with motile aeromonad septicemia that was collected from an ornamental fish-breeding farm in Sri Lanka.

Since post-harvest improvement of food quality depends on the pre-harvest stage, controlling food quality at the pre-harvest stage is being recognized as an important aspect of food processing technology. n-3 Long-chain polyunsaturated fatty acids (n-3 LCPUFAs) are considered important factors in the suppression of cardiovascular disease and development of the infant brain and visual functions. Fish meat generally contains a larger amount of n-3 LCPUFAs than meat from terrestrial animals, but the amount of n-3 LCPUFAs in fish meat depends on their dietary fatty acid intake. In order to supply n-3 LCPUFAs to consumers, we developed a finishing-up method, through a 4-day lysine-deficient diet feeding for rainbow trout (Oncorhynchus mykiss) meat. This 4-day lysine deficiency did not affect fish body weight, while significantly increased the total lipid content in the muscle tissue. In addition, docosahexaenoic acid and total n-3 fatty acid contents increased significantly in the meat throughout the 4-day finishing treatment. We concluded that the finishing-up method using short-term lysine-deficient diet feeding enables us to enrich fish meat with n-3 fatty acids for human consumption.

This paper is dedicated to Professor K. Alex Muller. In 1986, 30 years ago, high temperature superconductivity was discovered by George Bednorz and Alex Muller in copper oxides, by their epoch-making insight that higher superconducting transition temperature could be achieved by strong interactions with Jahn-Teller (JT) distortion of the constituting CuO6 octahedron unit. Paying special attention to the experimental fact that the doped holes induce a new kind of deformation of CuO6 octahedrons in copper oxide superconductors called the anti-JT effect, we developed a non-rigid band theory for calculating the energy bands of holes traversing in the deformed potential field. Thus, we obtained a complete picture of the doping-induced alteration in the electronic structure of Sr-doped La2CuO4, La2−xSrxCuO4 (LSCO), the simplest copper oxide superconductor. This description has brought the following major advances: The Fermi surface structure of this cuprate in the underdoped region consists of Fermi pockets in the antinodal region and Fermi arcs in the nodal region, and thus that the origin of a so-called pseudogap is closely related to the existence of Fermi pockets. Moreover, we have shown that the carriers on the Fermi pockets contribute to the phonon mechanism in d-wave superconductivity. Further it is shown that the strong electron–phonon coupling in copper oxides is due to the orbital near- degeneracy, and this gives rise to high temperature superconductivity [The present paper is based on our recent paper uploaded in arXiv 1608.08338].

Lipoprotein lipase (LPL) plays a critical role in the metabolism of circulating triacylglycerols (TAGs) packaged in lipoproteins. Fish have two LPL genes, encoding the LPL1 and LPL2 enzymes, but their functions are not yet clearly understood. To provide a basis for further investigation, we cloned a cDNA encoding LPL from the liver of adult medaka Oryzias latipes. The cloned LPL gene was found to share a high identity with LPL1 genes from several fish species and was denoted medaka LPL1. Screening against publicly available medaka expressed sequence tag (EST) databases revealed that LPL1 transcripts are abundant in ESTs from various developmental stages and tissues. The EST screening also identified a second LPL-like gene, denoted medaka LPL2, the transcripts of which were found exclusively in EST libraries from embryonic stages. The LPL1 cDNA obtained by a combination of 3′ and 5′ rapid amplification of cDNA ends was 2,259 bp, with an open reading frame of 1,551 bp encoding 516 amino acids. Quantitative real-time PCR further confirmed the ubiquitous distribution of LPL1 transcripts, with high levels in the liver and visceral adipose tissue, and the lowest level in the intestine. A relatively high expression of the LPL1 gene was also found in the brain, suggesting the potential function of LPL1 in this organ.

Hormone-sensitive lipase (HSL) is an important regulator of lipolysis in mammals, but little is known about its function in other animals. For a better understanding of fish HSL and potential application of the HSL-mediated lipolysis in aquaculture, we cloned HSL cDNAs from Japanese flounder Paralichthys olivaceus. The full-length cDNAs of two HSL genes, designated HSL1 and HSL2, consisted of 2,922 and 2,832 bp, respectively. RT-PCR showed that their transcripts were abundant in the inclinator muscle of fin, liver, and skeletal muscle. Quantitative real-time PCR further revealed that the transcripts of HSL1 and HSL2 genes were broadly expressed in all tissues tested, with the highest abundance in the inclinator muscle of fin. The inclinator muscle of fin also contained many adipocytes. In addition to triacylglycerols, considerable amounts of cholesteryl esters and non-esterified fatty acids were detected in the lipids extracted from the inclinator muscle of fin. Finally, in situ hybridization localized the HSL1 transcripts to the adipocytes observed in the inclinator muscle of fin. Together, these results suggest that the inclinator muscle of fin is a lipid storage site that releases non-esterified fatty acids for aerobic fin movement, possibly through HSL-mediated lipolysis.

Quality control of seafood has been one major purpose of scientific researches on fish and shellfish. In this monograph, we deal with the utilization of biological responses in the preharvest and postharvest stages of aquatic animals, (1) responses of fish muscle energy metabolisms to environmental temperature changes in postmortem stages, (2) responses of fish and shellfish chromatophore to extrinsic stimuli, and (3) responses of fish to the oral administration of phytosterol related compounds. These approaches will not only confer the improvement of seafood qualities but the addition of extra value to seafood for human consumption. Because animals respond biologically to many factors, comprehensive understanding of biological responses of aquatic animals to environmental factors will lead to the further improvement of seafood qualities.

The effects of setting (suwari) at around 40 °C on the breaking strength and breaking strain rate of thermal gels treated at 85 °C for 20 min during the following processing step were examined in association with the polymerization and degradation of myosin heavy chains (MHCs) for surimi prepared from white croaker, walleye pollack and deepsea bonefish. In the case of white croaker and walleye pollack, maximum values of breaking strength and breaking strain rate were obtained after suwari at 30–40 °C for both 30 and 60 min, at which temperature MHCs were polymerized. In comparison, these textual properties of the thermal gels decreased in surimi prepared from deepsea bonefish after suwari at around 38 °C for 30 min and at around 32 °C for 60 min, with concomitant degradation products of MHC. The textual properties of deepsea bonefish after suwari at temperatures >45 °C tended to be almost the same as those after suwari at temperatures of

Little is known about whether mammals use gustatory sense to detect compounds produced from oxidized oil as a taste or only use olfactory sense to detect the compounds as aroma. The present study examined the effects of oxidized arachidonic acid (AA) ethyl ester and hexanal, one predominant compound in oxidized AA, on mouse taste perception of monosodium glutamate (MSG).We examined the effects of oxidized ethyl AA and hexanal on chorda tympani (CT) nerve response to MSG using mouse electrophysiological technique. In addition, we evaluated the effects of aliphatic aldehydes and alcohol which are compounds structurally related to hexanal with carbon chain lengths or a functional group different from hexanal on taste perception of MSG using behavioral and electrophysiological studies.The CT nerve responses to 10, 20, and 50 mM MSG with water extracts of oxidized ethyl AA was higher than that to MSG alone. A total of 1000 µM hexanal and pentanal enhanced mouse taste response to MSG, but 1000 µM propanal and 1-hexanol failed to increase the responses.The products of oxidized ethyl AA and hexanal would enhance the taste sensation of MSG, which suggests that CT nerve input should be important for projection to the behavioral responses. The carbon chain length and the functional group of hexanal would be key factors of the hexanal effect on mouse taste perception of MSG.

Pufferfishes belonging to the genus Tetraodon form one of the largest groups in the family Tetraodontidae. This group consists of more than 20 species distributed across freshwater, as well as brackish and coastal waters, of Africa and Southeast Asia. However, their phylogenetic and evolutionary relationships are still ambiguous. In the present study, mitochondrial genes encoding 16S rRNA and cytochrome b were sequenced for 17 Tetraodon species collected from various areas mentioned above. Supermatrix analysis based on the complete sequences of the two genes from Tetraodon species was performed using a tree with 50 tetraodontid species (including 7 Tetraodon species) as a backbone. The obtained phylogenetic tree classified Tetraodon species into three groups, correlating well with their habitats, such as Asian freshwater, Asian brackish water, and African freshwater. We also showed that salinity tolerance of Asian freshwater species T. cochinchinensis was apparently lower than that of Asian brackish water species T. nigroviridis, suggesting that the speciation of Tetraodon species in the Asian freshwater group was caused by the molecular evolution associated with osmotic regulation.

Four quality grades (excellent, good, acceptable, and “not acceptable”) of yellowfin tuna meat (Thunnus albacares), as judged by a professional appraiser, were compared based on the red/ox state and extractability of myoglobin (Mb). As a result, the metMb ratio of the “not acceptable” grade of meat was significantly higher than that of the other higher-grade samples. In contrast, the highest ratio of oxyMb was found in the “excellent” meat, followed by good > acceptable > “not acceptable” meats. Color measurement revealed significant differences in a* value between the different grades of meat, but showed essentially no difference in L* and b* values. Both a* value and redness index (a*/b*) showed high correlation coefficients with metMb ratio. Mb extractability tended to be higher in the higher grade of meat. In conclusion, the commercial appraisal of tuna meat quality was demonstrated to be reliable.

The taste and extractive components of boiled dorsal muscle and broth prepared from half-smooth golden puffer Lagocephalus spadiceus caught in Japan and from those imported from China were compared. In the sensory test, the first taste, elasticity, and saltiness of boiled muscle from Japanese (domestic) fish were higher than those of the imported fish, whereas the orthonasal fishy smell of the imported fish was higher than that of the domestic fish. The first taste, aftertaste, retronasal fishy smell, sweetness, saltiness, and umami of the broth prepared from dorsal muscle of the domestic fish were higher than those of the imported fish, whereas orthonasal fishy smell and bitterness of the imported fish were higher than those of the domestic fish. Most panelists preferred the overall taste of the domestic fish to that of the imported fish. The concentration of trimethylamine in the trichloroacetic acid extracts from boiled muscle and broth of the imported fish was higher than that of the domestic fish, suggesting that this substance contributes to the orthonasal fishy smell of the imported fish.

Adiponectin is one of the adipokines secreted mainly from adipocytes in mammals. In rainbow trout, however, adiponectin is highly expressed in skeletal muscle. Although it has been suggested that fish skeletal muscle contains adipocytes, their endocrine function and distribution are poorly understood. Recently, an EST analysis of rainbow trout found that heart-type fatty acid binding protein (H-FABP), a member of the intracellular fatty acid binding protein family, encodes an adipose-specific gene. In this study, we produced anti-adiponectin and H-FABP antibodies and investigated the distribution of adipocytes and related cells in skeletal muscle of rainbow trout. The adiponectin signal was detected at around 75 kDa in muscle in Western blotting. Since the molecular mass of rainbow trout adiponectin is around 25 kDa, this 75 kDa band would be a trimer. For H-FABP, the signal band was detected at around 15 kDa. Immunohistochemistry of skeletal muscle sections indicated that adiponectin and H-FABP signals were present outside of muscle cells and throughout the muscle tissues, suggesting the existence of adipocyte-related cells in these regions. These results will contribute to our understanding of energy metabolism in fish skeletal muscle.

Here we report the draft genome sequence and annotation of A. veronii strain Ae52 isolated from the kidney of a morbund, septicaemic gold fish (Carassius auratus) in Sri Lanka. This clinical isolate showed resistance to multiple antimicrobials; amoxicillin, neomycin, trimethoprim-sulphonamide, chloramphenicol, tetracycline, enrofloxacin, erythromycin and nitrofurantoin. The size of the draft genome is 4.56 Mbp with 58.66% of G + C content consisting 4328 coding sequences. It harbors a repertoire of putative antibiotic resistant determinants that explains the genetic basis of its resistance to various classes of antibiotics. The genome sequence has been deposited in DDBJ/EMBL/GenBank under the accession numbers BDGY01000001-BDGY01000080.

Citrobacter freundii is a Gram-negative opportunistic pathogen associated with many infectious conditions including septicemia in humans and animals. Here, we announce the draft genome sequences of two multidrug-resistant C. freundii strains (CF04 and A41) isolated from septicemic giant gourami ( Osphronemus goramy ) collected from aquaria in Sri Lanka.

Rotifers are microscopic cosmopolitan zooplankton used as models in ecotoxicological and aging studies due to their several advantages such as short lifespan, ease of culture, and parthenogenesis that enables clonal culture. However, caution is required when measuring their survival time as it is affected by maternal age and maternal feeding conditions. Here we provide a protocol for powerful and reproducible measurement of the survival time in Brachionus rotifers following a careful synchronization of culture conditions over several generations. Empirically, poor synchronization results in early mortality and a gradual decrease in survival rate, thus resulting in weak statistical power. Indeed, under such conditions, calorie restriction (CR) failed to significantly extend the lifespan of B. plicatilis although CR-induced longevity has been demonstrated with well-synchronized rotifer samples in past and present studies. This protocol is probably useful for other invertebrate models, including the fruitfly Drosophila melanogaster and the nematode Caenorhabditis elegans, because maternal age effects have also been reported in these species.

Gene expression in the muscle of rainbow trout Oncorhynchus mykiss fed either ad libitum once a week (RF, restricted feed group) or ad libitum twice per day (control) was compared to identify those genes differently regulated during restricted feeding. After 1 month, the increase in the size of the RF fish was significantly less than that of the control fish. A microarray analysis of 37,394 unique sequences revealed that 2,701 transcripts differed by more than twofold between the control and RF groups. In the RF group, one and three genes involved in fatty acid β-oxidation were down- and up-regulated, respectively, and five glycolysis-related genes were down-regulated. The genes for growth hormone receptors-1 and -2 were up-regulated in the RF group. A number of adipocyte-related and adiponectin genes were down-regulated in the RF group, suggesting that lipid accumulation might be suppressed in this group. These results suggest that adiponectin and growth hormone signaling plays an active role in the control of energy metabolism during restricted food intake.

In this Festschrift paper celebrating Prof. Jacques Friedel 90 years’ birthday, we review the latest developments of the model proposed by Kamimura and Suwa, which bears important characteristics born from the interplay of Jahn–Teller physics and Mott physics. First it is shown that the feature of Fermi surfaces is the Fermi pockets constructed by doped holes under the coexistence of a metallic state and of local antiferromagnetic order. Then the phonon-involved mechanism based on the Kamimura–Suwa model is discussed; it leads to d-wave superconductivity. Further it is shown that T c is higher in the cuprates with CuO5 pyramid than those with CuO6 octahedron. Finally a recent theoretical result on the energy distribution curves (EDCs) of angle-resolved photoemission spectroscopy (ARPES) below T c is presented, and a remark is made on the phase diagram for underdoped cuprates.

Growth hormone (GH) is an important hormone with primary roles in growth, lipid metabolism, osmoregulation, and immunity in fish, via the growth hormone receptor (GHR). We have cloned cDNAs from the torafugu pufferfish Takifugu rubripes encoding two distinct GHRs. Phylogenetic analysis of these GHRs together with their counterparts from other fish led to the identification of 1914- and 1695-bp cDNAs for torafugu GHR1 and GHR2, respectively. The deduced amino acid sequences of GHR1 and GHR2 showed 34% identity and, in comparison to torafugu GHR1, torafugu GHR2 lacked three extracellular cysteine and five intracellular tyrosine residues, suggesting that the two torafugu GHRs have different functions in GH/GHR signaling. Real-time PCR revealed that the transcript abundance of torafugu GHR1 and GHR2 tended to be high in fast muscle, slow muscle, and liver. Notably, the relative mRNA level of torafugu GHR1 was significantly higher in fast muscle, in comparison to the GHR1s from other fish reported to date where the highest relative mRNA levels have been found in the liver. Taken together with the well-known lipolytic effects of GH on fish liver, these expression patterns of torafugu GHRs suggest its liver-specific lipid accumulation.

Metabolic syndrome is a cluster of risk factors including insulin resistance and type 2 diabetes and is found to associate partly with chronic stress at work in human. Adiponectin circulates in mammal blood mainly as a low molecular weight (LMW) trimer, hexamer, and a high molecular weight (HMW) multimers. Low circulating levels of adiponectin are related to metabolic syndrome. We have then investigated the influence of immobilization stress on plasma adiponectin concentrations in mice. Relative LMW and HMW adiponectin levels were markedly reduced by immobilization stress (0.66±0.07 and 0.59±0.06 after 102 h, respectively), significantly different from the control values (p