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Promoting the thermogenic function of brown adipose tissue (BAT) is a promising strategy to combat obesity and metabolic disorders. While much is known about the transcriptional regulation of BAT activation, however, the underlying mechanism of post-transcriptional control by RNA binding proteins remains largely unknown. Here, we found that RNA binding protein Y-box binding protein 1 (YBX1) expression was abundant in BAT and induced by cold exposure and a β-adrenergic agonist in mice. Loss-of-function experiments showed that YBX1 deficiency inhibited mouse primary brown adipocyte differentiation and thermogenic function. Further study showed that YBX1 positively regulates thermogenesis through enhancing mitophagy. Mechanistically, RNA immunoprecipitation identified that YBX1 directly targeted the transcripts of PTEN-induced kinase 1 (Pink1) and parkin RBR E3 ubiquitin-protein ligase (Prkn), two key regulators of mitophagy. RNA decay assay proved that loss of YBX1 decreased mRNA stability of Pink1 and Prkn, leading to reduced protein expression, thereby alleviating mitophagy and inhibiting thermogenic program. Importantly, in vivo experiments demonstrated that YBX1 overexpression in BAT promoted thermogenesis and mitophagy in mice. Collectively, our results reveal novel insight into the molecular mechanism of YBX1 in post-transcriptional regulation of PINK1/PRKN-mediated mitophagy and highlight the critical role of YBX1 in brown adipogenesis and thermogenesis.

As one of the key points related to meat quality, skeletal muscle fibre type is determined by energy metabolism and genetic factors, but its transformation could be also greatly influenced by many factors. Thymol, the primary effective ingredients of thyme, is well known for its anti-oxidation and anti-inflammatory, while little is known about its effect on skeletal muscle oxidative metabolism and fibre type switch. Therefore, in order to investigate its effects and possibility to be applied in livestock production, 36 150-day-old fattening Pigs were fed with different diet for six-week experiment. As a result, the drip loss ratio of longissimus dorsi (LD) was significantly reduced (p < .05). Oxidative metabolism-related enzyme activity, the mRNA levels and protein expression of COX5B and PGC1α, mRNA level of myosin heavy chain I (MyHC I) and protein level of MyHC IIa were significantly upregulated (p < .05). While compared with control group, the protein expression of MyHC IIb was significantly decreased (p < .05). The result revealed that thymol could promote the oxidative metabolism in the muscle of pigs and improve the meat quality to a certain extent.

This study aimed to investigate the effects of exogenous H2 S on the proliferation of porcine mammary gland epithelial cells (PMECs) and explore the underlying mechanisms. We found that exposure of PMECs to NaHS, at concentrations ranging from 10 to 200 µM, stimulated cell proliferation. However, high concentration of NaHS (600 µM) inhibited PMECs proliferation. Accordingly, 10 µM NaHS significantly increased the percentage of cells undergoing DNA replication, elevated the mRNA and/or protein expression of Cyclin A2, Cyclin D1/3, Cyclin E2 and PCNA, and decreased p21 mRNA expression. In contrast, 600 µM NaHS elicited the opposite effects to that of 10 µM NaHS. In addition, PI3 K/Akt and mTOR signaling pathways were activated or inhibited in response to 10 or 600 µM NaHS, respectively. Furthermore, the promotion of PMECs proliferation, the change of proliferative genes expression, and the activation of mTOR signaling pathway induced by 10 µM NaHS were effectively blocked by PI3 K inhibitor Wortmannin. Similarly, inhibition of mTOR with Rapamycin totally abolished the 10 µM NaHS-induced stimulation of PMECs proliferation and alteration of proliferative genes expression, with no influence on PI3 K/Akt signaling pathway. Moreover, constitutive activation of Akt pathway via transfection of Akt-CA completely eliminated the inhibition of PMECs proliferation and mTOR signaling pathway, and the change of proliferative genes expression induced by 600 µM NaHS. In conclusion, our findings provided evidence that exogenous H2 S supplied by NaHS exerted biphasic effects on PMECs proliferation, with stimulation at lower doses and suppression at high dose, through the intracellular PI3 K/Akt-mTOR signaling pathway.

Skeletal muscle atrophy due to excessive protein degradation is the main cause for muscle dysfunction, fatigue, and weakening of athletic ability. Endurance exercise is effective to attenuate muscle atrophy, but the underlying mechanism has not been fully investigated. α-Ketoglutarate (AKG) is a key intermediate of tricarboxylic acid cycle, which is generated during endurance exercise. Here, we demonstrated that AKG effectively attenuated corticosterone-induced protein degradation and rescued the muscle atrophy and dysfunction in a Duchenne muscular dystrophy mouse model. Interestingly, AKG also inhibited the expression of proline hydroxylase 3 (PHD3), one of the important oxidoreductases expressed under hypoxic conditions. Subsequently, we identified the β2 adrenergic receptor (ADRB2) as a downstream target for PHD3. We found AKG inhibited PHD3/ADRB2 interaction and therefore increased the stability of ADRB2. In addition, combining pharmacologic and genetic approaches, we showed that AKG rescues skeletal muscle atrophy and protein degradation through a PHD3/ADRB2 mediated mechanism. Taken together, these data reveal a mechanism for inhibitory effects of AKG on muscle atrophy and protein degradation. These findings not only provide a molecular basis for the potential use of exercise-generated metabolite AKG in muscle atrophy treatment, but also identify PHD3 as a potential target for the development of therapies for muscle wasting.—Cai, X., Yuan, Y., Liao, Z., Xing, K., Zhu, C., Xu, Y., Yu, L., Wang, L., Wang, S., Zhu, X., Gao, P., Zhang, Y., Jiang, Q., Xu, P., Shu, G. α-Ketoglutarate prevents skeletal muscle protein degradation and muscle atrophy through PHD3/ADRB2 pathway.

Microwave-assisted three-component reaction has been established for the synthesis of benzodiazepines. This reaction promoted by HOAc was conducted by using readily available and inexpensive starting materials in water under microwave irradiation. The present green synthesis shows fascinating characteristics such as the use of water as the reaction solution, concise one-pot conditions, short reaction periods, easy purification, and reduced waste production without the use of any strong acids or metal promoters.

L-arginine (L-Arg), the precursor of nitric oxide (NO), plays multiple important roles in nutrient metabolism and immune regulation. L-Arg supplement serves as a potential adjunctive therapy for severe malaria, because it improves NO bioavailability and reverses endothelial dysfunction in severe malaria patients. In this study, we investigated the effect of dietary L-Arg supplement on host immune responses during subsequent malaria infection using the Plasmodium yoelii 17XL - BALB/c mouse model. We have shown that pretreatment of mice with L-Arg significantly decreased parasitemia and prolonged the survival time of mice after infection. L-Arg supplement led to significant increases in activated CD4(+)T-bet(+)IFN-γ(+) T cells and F4/80(+)CD36(+) macrophages during early-stage infection, which were accompanied by enhanced synthesis of IFN-γ, TNF-α and NO by spleen cells. Moreover, L-Arg-pretreated mice developed more splenic myeloid and plasmacytoid dendritic cells with up-regulated expression of MHC II, CD86 and TLR9. In comparison, L-Arg treatment did not change the number of regulatory T cells and the level of anti-inflammatory cytokine IL-10. Taken together, our results showed that L-Arg pretreatment could improve the protective immune response in experimental malaria infection in mice, which underlines potential importance of L-Arg supplement in malaria-endemic human populations.

MicroRNAs (miRNAs) are an abundant class of small regulatory RNAs that negatively regulate gene expression at the post-transcriptional level. Although an increasing number of porcine miRNAs recently have been identified, research has yet to identify the full repertoire of miRNAs in pig skeletal and adipose tissues and their differences between breeds. We extracted small RNA from skeletal muscle and adipose tissues of Landrace and Lantang pigs, and the expression of a total of 184 known porcine miRNAs (113 from Solexa sequencing and 171 from miRNA chip hybridization) as well as 521 novel miRNA candidates was detected. Moreover, 20 miRNAs were selected randomly from the 184 miRNAs and analysed by quantitative real-time PCR to confirm the aforementioned results. In the skeletal muscle tissues, 21 miRNAs were up-regulated in Lantang and another 33 were highly expressed in Landrace pigs. In the adipose tissues, 25 miRNAs were down-regulated in Lantang and another 23 were lowly expressed in Landrace pigs. miRNA divergence between tissues was also detected in this study. Ten miRNAs were highly expressed in the skeletal muscle tissue in comparison with adipose tissue, and another 10 miRNAs exhibited the opposite expression profile. To investigate the regulatory mechanism of the miRNAs in muscle and adipose tissues, the 10 miRNAs with the most divergent expression profiles were functionally categorized using the Kyoto Encyclopedia of Genes and Genomes database. Most of the miRNAs strongly corresponded to myogenesis and adipogenesis processes. In addition, 84 of the 521 miRNA candidates were potentially porcine-specific miRNAs. This study adds new valuable information to comparative miRNA profiles of skeletal muscle and adipose tissues in porcine species. The great diversity of miRNA composition and expression levels both between breeds and between tissues suggests that a complex regulatory network exists in porcine subcutaneous fat development.

CD4+ CD25+ regulatory T (Treg) cells expressing Foxp3+ play a critical role in maintaining immune homoeostasis and controlling excessive immune responses. However, controversy about the immunoregulatory role of Treg cells exists in malaria studies. Given the role of maintenance of Foxp3 expression in Treg cells’ activities, we investigated whether anti-CD25 mAb (7D4 clone) treatment affects Foxp3 expression in CD4+ T cells in DBA/2 mice infected with Plasmodium chabaudi chabaudi AS (P. c. chabaudi AS). We found that DBA/2 mice succumbed to P. c. chabaudi AS infection, which was accompanied by increased expression of Foxp3 in CD4+ T cells at the peak parasitemia. In contrast, Foxp3 expression was impaired in CD25-depleted mice with 7D4 mAb treatment, leading to delayed parasitemia and extended survival of infected mice. Production of IFN-γ, TNF-α and IL-6, as well as NO was significantly enhanced in CD25-depleted mice. The majority of CD4+ CTLA-4+ cells expressed high levels of Foxp3 (Foxp3hi cells) in control mice with P. c. chabaudi AS infection. However, the number of CD4+ Foxp3hiCTLA-4+ cells was reduced in CD25-depleted mice. Together, these data suggest that CD4+ Foxp3hiCTLA-4+ cells may be involved in regulating the intensity of pro-inflammatory responses via CTLA-4.

Fatty acids translocase (FAT) is a transporter that facilitate long-chain fatty acids uptake as well as lipid accretion. To investigate the potential role of FAT in different adipose tissues, we investigated the cDNA structure of porcine FAT (pFAT) and analysed the tissue distribution of pFAT mRNA. The FAT mRNA expression profiles in the pre-adipocytes isolated from subcutaneous and intramuscular fat were also compared during cell differentiation. The results showed that 2389 bp porcine cDNA (DQ192230) had 87% homology with human FAT, 83% with mouse FAT, 82% with rat FAT and 67.5% with chicken FAT. Alignment of deduced amino acids sequence showed 82.4% homology with human FAT, 83.3% with mouse FAT and 85% with rat FAT. RT-PCR analysis revealed that the pFAT mRNA had a wide-spread expression in most tissues except for the brain. The higher level transcript was detected in visceral fat tissue by real-time quantitative RT-PCR. Interestingly, the pFAT mRNA expression level was dramatically increased in the primary culture pre-adipocytes derived from intramuscular fat and this consistent with the cellular lipid accretion. However, a sustained lower-level transcript was also found in the adipocytes from subcutaneous fat. The present study indicated that pFAT mRNA had a differential expression in subcutaneous, visceral and intramuscular fat depots. The data presented here provide further proof that pFAT might be involved in the modulation of the temporal and spatial fat depots.

This described green synthesis shows several attractive characteristics such as the use of water as reaction medium, simple reaction conditions, short reaction times and an easy work-up.

A series of N-carboxymethylacridine-1,8-dione derivatives were synthesized by one-pot reaction of aldehyde, dimedone and glycine in glycol under microwave irradiation without catalyst with excellent yields (78-92%) and short reaction time (4-8min). And the reaction was not only suitable for aromatic monoaldehyde, but also aromatic dialdehyde.

Four-component cyclocondensation of aromatic aldehydes, malononitrile, dimedone and ammonium acetate proceeds under microwave irradiation in solvent free conditions to give highly functionalized hexahydroquinolines in excellent yields.

A series of 5-aryl substituted 2-amino-5,8-dihydropyrido[2,3-d]pyrimidin-4,7-diones were synthesized through one-pot condensation of 2,6-diaminopyrimidin-4-one, aldehyde and Meldrum's acid using glycol as energy transfer agent under microwave irradiation without catalyst. The one-pot protocol in the absence of catalyst has the advantage of good yield (86-95%), short route and reaction time (3-6 min) and environmentally friendly.

A series of 10-methyl-1,2,3,4,5,6,7,8,9,10-decahydroacridine-1,8-dione derivatives were synthesized by one-pot reaction of aldehyde, dimedone or 1,3-cyclohexanedione and methylamine in glycol or water under microwave heating without catalyst. The method has the advantage of short routine and reaction time, high yields as well as friendly environment. And the reaction was not only suitable for aliphatic and aromatic monoaldehyde, but also for aromatic dialdehyde.

A series of new N-cyclopropyldecahydroacridine-1,8-dione derivatives were synthesized by one-pot reaction of aromatic aldehyde, dimedone (or 1,3-cyclohexanedione) and cyclopropanamine in solution of glycol and water under microwave irradiation with excellent yields (78-94%) and short reaction time (5-10 min).

A series of new and significative bifunctional compounds containing two pyrazolo[3,4-b]pyridine moieties has been synthesized through a rapid one-pot three-component reaction of dialdehyde, 5-amino-3-methyl-1-phenylpyrazole and active methylene compounds in glycol under microwave irradiation without catalyst. The method has the advantages of good yield (85-98%), short route and reaction time (45-300s), wide reaction scope and easy work-up procedure.

A series of N-carboxymethylacridine-1,8-dione derivatives were synthesized by one-pot reaction of aldehyde, dimedone and glycine in glycol under microwave irradiation without catalyst with excellent yields (78-92%) and short reaction time (4-8min). And the reaction was not only suitable for aromatic monoaldehyde, but also aromatic dialdehyde.

Four-component cyclocondensation of aromatic aldehydes, malononitrile, dimedone and ammonium acetate proceeds under microwave irradiation in solvent free conditions to give highly functionalized hexahydroquinolines in excellent yields.

A simple and efficient synthesis of 2-amino pyrido[2,3-d]pyrimidine derivatives was accomplished via a three-component reaction under microwave irradiation without catalyst. This method had many dramatic advantages such as the short reaction time, high yield, and broad substrate scope, as well as convenient operation. We provide new series of potential biologically active compounds as inhibitors of Cdk4.

A series of 4'-aryl-2,2':6',2"-terpyridines have been prepared by the one-pot reaction of 2-acetylpyridine with aromatic aldehydes in the presence of ammonium acetate under microwave irradiation. This method has the advantages of shorter route, easier workup, shorter reaction time, higher yield and more environmentally friendly conditions, compared to the conventional ones.