Ketogenic essential amino acids replacement diet ameliorated hepatosteatosis with altering autophagy-associated molecules

Ketogenic amino acid (KAA) replacement diet has been shown to cure hepatic steatosis, a serious liver disease associated with diverse metabolic defects. In this study, we investigated the effects of KAA replacement diet on nutrition sensing signaling pathway and analyzed whether induction of hepatic autophagy was involved. Mice are fed with high fat diet (HFD) or KAA replacement in high-fat diet (30% fat in food; HFD)-fed (HFD^KAAR) and sacrificed at 8, 12, 16 weeks after initiation of experimental food. Hepatic autophagy was analyzed in protein expression of several autophagy-associated molecules and in light chain-3 green fluorescent protein (LC-3 GFP) transgenic mice. HFD^KAAR showed increased AMP-activated protein kinase (AMPK) phosphorylation and enhanced liver kinase B1 (LKB1) expression compared to control HFD-fed mice. The KAA-HFD-induced activation of AMPK was associated with an increased protein expression of sirtuin 1 (Sirt1), decreased forkhead box protein O3a (Foxo3a) level, and suppression of mammalian target of rapamycin (mTOR) phosphorylation compared with the HFD-fed mice. The intervention study revealed that a KAA-replacement diet also ameliorated all the established metabolic and autophagy defects in the HFD-fed mice, suggesting that a KAA-replacement diet can be used therapeutically in established diseases. These results indicate that KAA replacement in food could be a novel strategy to combat hepatic steatosis and metabolic abnormalities likely involvement of an induction of autophagy.     

A clinical study of the efficacy of a single session of individual exercise for depressive patients,assessed by the change in saliva free cortisol level

Background

The efficacy of physical exercise as an augmentation to pharmacotherapy with antidepressants for depressive patients has been documented. However, to clarify the effectiveness of exercise in the treatment of depression, it is necessary to distinguish the effect of the exercise itself from the effect of group dynamics. Furthermore, an objective measurement for estimation of the effect is needed. Previous reports adopted a series of group exercises as the exercise intervention and mainly psychometric instruments for the measurement of effectiveness. Therefore, this clinical study was done to examine the effectiveness of a single session of individual exercise on depressive symptoms by assessing the change in saliva free cortisol level, which reflects hypothalamic-pituitary-adrenocortical axis function that is disturbed in depressive patients.

Method

Eighteen medicated patients, who met the DSM-IV-TR criteria for major depressive disorder, were examined for the change in saliva free cortisol levels and the change in subjective depressive symptoms before and after pedaling a bicycle ergometer for fifteen minutes. Within a month after the exercise session, participants conducted a non-exercise control session, which was sitting quietly at the same time of day as the exercise session.

Results

Depressed patients who participated in this study were in remission or in mild depressive state. However, they suffered chronic depression and had disturbed quality of life. The saliva free cortisol level and subjective depressive symptoms significantly decreased after the exercise session. Moreover, the changes in these variables were significantly, positively correlated. On the other hand, although the subjective depressive symptoms improved in the control session, the saliva free cortisol level did not change.

Conclusion

For the first time in depressive patients, we were able to show a decrease in the saliva free cortisol level due to physical exercise, accompanied by the improvement of subjective depressive symptoms. This identified a possible influence of exercise on the hypothalamic-pituitary-adrenal axis in depression.These results suggest the utility of assessing the effect of physical exercise by saliva free cortisol level in depressive patients who suffer from bio-psycho-social disability.

     

Validity of ultrasound muscle thickness measurements for predicting leg skeletal muscle mass in healthy Japanese middle-aged and older individuals

Background

The skeletal muscle mass of the lower limb plays a role in its mobility during daily life. From the perspective of physical resources, leg muscle mass dominantly decreases after the end of the fifth decade. Therefore, an accurate estimate of the muscle mass is important for the middle-aged and older population. The present study aimed to clarify the validity of ultrasound muscle thickness (MT) measurements for predicting leg skeletal muscle mass (SM) in the healthy Japanese middle-aged and older population.

Findings

MTs at four sites of the lower limb and the bone-free lean tissue mass (LTM) of the right leg were determined using brightness-mode ultrasonography and dual-energy X-ray absorptiometry (DXA), respectively, in 44 women and 33 men, 52- to 78-years old. LTM was used as a representative variable of leg skeletal muscle mass. In the model-development group (30 women and 22 men), regression analysis produced an equation with R² and standard error of the estimate (SEE) of 0.958 and 0.3 kg, respectively: LTM (kg) = 0.01464 × (MT_SUM×L) (cm²) - 2.767, where MT_SUM is the sum of the product of MTs at four sites, and L is length of segment where MT is determined. The estimated LTM (7.0 ± 1.7 kg) did not significantly differ from the measured LTM (7.0 ± 1.7 kg), without a significant systematic error on a Bland-Altman plot. The application of this equation for the cross-validation group (14 women and 11 men) did not yield a significant difference between the measured (7.2 ± 1.6 kg) or estimated (7.2 ± 1.6 kg) LTM and systematic error.

Conclusion

The developed prediction equation may be useful for estimating the lean tissue mass of the lower extremity for the healthy Japanese middle-aged and older population.     

Relative Biological Effectiveness of HZE Particles for Chromosomal Exchanges and Other Surrogate Cancer Risk Endpoints

The biological effects of high charge and energy (HZE) particle exposures are of interest in space radiation protection of astronauts and cosmonauts, and estimating secondary cancer risks for patients undergoing Hadron therapy for primary cancers. The large number of particles types and energies that makeup primary or secondary radiation in HZE particle exposures precludes tumor induction studies in animal models for all but a few particle types and energies, thus leading to the use of surrogate endpoints to investigate the details of the radiation quality dependence of relative biological effectiveness (RBE) factors. In this report we make detailed RBE predictions of the charge number and energy dependence of RBE’s using a parametric track structure model to represent experimental results for the low dose response for chromosomal exchanges in normal human lymphocyte and fibroblast cells with comparison to published data for neoplastic transformation and gene mutation. RBE’s are evaluated against acute doses of γ-rays for doses near 1 Gy. Models that assume linear or non-targeted effects at low dose are considered. Modest values of RBE (<10) are found for simple exchanges using a linear dose response model, however in the non-targeted effects model for fibroblast cells large RBE values (>10) are predicted at low doses <0.1 Gy. The radiation quality dependence of RBE’s against the effects of acute doses γ-rays found for neoplastic transformation and gene mutation studies are similar to those found for simple exchanges if a linear response is assumed at low HZE particle doses. Comparisons of the resulting model parameters to those used in the NASA radiation quality factor function are discussed.     

Germline recombination in a novel Cre transgenic line,Prl3b1‐Cre mouse

Spermatogenesis is a complex and highly regulated process by which spermatogonial stem cells differentiate into spermatozoa. To better understand the molecular mechanisms of the process, the Cre/loxP system has been widely utilized for conditional gene knockout in mice. In this study, we generated a transgenic mouse line that expresses Cre recombinase under the control of the 2.5 kbp of the Prolactin family 3, subfamily b, member 1 (Prl3b1) gene promoter (Prl3b1‐cre). Prl3b1 was initially reported to code for placental lactogen 2 (PL‐2) protein in placenta along with increased expression toward the end of pregnancy. PL‐2 was found to be expressed in germ cells in the testis, especially in spermatocytes. To analyze the specificity and efficiency of Cre recombinase activity in Prl3b1‐cre mice, the mice were mated with reporter R26GRR mice, which express GFP ubiquitously before and tdsRed exclusively after Cre recombination. The systemic examination of Prl3b1‐cre;R26GRR mice revealed that tdsRed‐positive cells were detected only in the testis and epididymis. Fluorescence imaging of Prl3b1‐cre;R26GRR testes suggested that Cre‐mediated recombination took place in the germ cells with approximately 74% efficiency determined by in vitro fertilization. In conclusion, our results suggest that the Prl3b1‐cre mice line provides a unique resource to understand testicular germ‐cell development. genesis 54:389–397, 2016. © 2016 Wiley Periodicals, Inc.     

Human Pluripotent Stem Cell-Derived Tumor Model Uncovers the Embryonic Stem Cell Signature as a Key Driver in Atypical Teratoid/Rhabdoid Tumor

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Self-Incompatibility Involved in the Level of Acetylcholine and cAMP

Elongation of pollen tubes in pistils after self-pollination of Lilium longiflorum cv. Hinomoto exhibiting strong gametophytic self-incompatibility was promoted by cAMP and also promoted by some metabolic modulators, namely, activators (forskolin and cholera toxin) of adenylate cyclase and inhibitors (3-isobutyl-1-methylxanthine and pertussis) of cyclic nucleotide phosphodiesterase. Moreover, the elongation was promoted by acetylcholine (ACh) and other choline derivatives, such as acetylthiocholine, L-α-phosphatidylcholine and chlorocholinechloride [CCC; (2-chloroethyl) trimethyl ammonium chloride]. A potent inhibitor (neostigmine) of acetylcholinesterase (AChE) as well as acetylcholine also promoted the elongation. cAMP enhanced choline acetyltransferase (ChAT) activity and suppressed AChE activity in the pistils, suggesting that the results are closely correlated with self-incompatibility in L. longiflorum. In short, it came to light that cAMP modulates ChAT (acetylcholine-forming enzyme) and AChE (acetylchoine-decomposing enzyme) activities to enhance the level of ACh in the pistils of L. logiflorum after self-incompatible pollination. These results indicate that the self-incompatibility on self-pollination is caused by low levels of ACh and/or cAMP.Key Words: pollen tubes, self-incompatibility, Lilium longiflorum, cAMP, acetylcholie, AChE, ChATCyclic AMP (cAMP) is an essential signaling molecule in both prokaryotes and eukaryotes.¹ The existence of cAMP in higher plants was questioned by some reviewers^2–4 in the mid 1970''s, so that many workers were discouraged from studying roles in plant biology. However, its presence was confirmed by mass spectrometry⁵ and infrared spectrometry⁶ in the early 1980''s and increasing evidence^7–12 now suggests that cAMP makes important contributions in plant cells, as in animals.Lily (Lilium longiflorum) exhibits strong gametophytic self-incompatibility.^13,14 Thus, elongation of pollen tubes in the pistil after self-incompatible pollination in L. longiflorum cv. Hinomoto stops halfway, in contrast to the case after cross-compatible pollination (cross with cv. Georgia).¹⁴ This self-incompatibility appears to be associated with the stress and self-incompatible pollination on stigmas of lilies results in activation and/or induction of enzymes such as NADH- and NADPH-dependent oxidases, xanthine oxidase, superoxide dismutase (SOD), catalase and ascorbate peroxidase in the pistils.¹⁵ The activities of NADH- and NADPH-dependent oxidases (O₂⁻-forming enzymes), however, are known to be suppressed by cAMP¹⁶ and increase in the level of cAMP in guinea pig neutrophils results in their decreased expression.¹⁷ The level of O₂⁻ reactions with SOD is also decreased by cAMP.¹⁸ In the case of the lily, inhibition of NADH- and NADPH-dependent oxidases by cAMP was found to be noncompetitive with NAD(P)H.¹⁶ We hypothesized that decrease in active oxygen species such as O₂⁻ and suppression of stress enzyme activities in self-pollinated pistils of lily by cAMP might cause elongation of pollen tubes after self-pollination and this proved to be the case. Namely, elongation of pollen tubes after self-incompatible pollination in lily was promoted by exogenous cAMP at a concentration as low as 10 nM, a conceivable physiological level.¹³ Moreover, similar elongation could be achieved with adenylate cyclase activators [forskolin(FK) and cholera toxin] and cAMP phosphodiesterase inhibitors [3-isobutyl-1-methylxanthine (IBMX) and pertussis toxin].^14,19 These phenomena led us to examine the involvement of endogenous cAMP in pistils after self-incompatible or cross-compatible pollination. As expected, the level of endogenous cAMP in pistils after self-pollination was approximately one half of that after cross-pollination. Furthermore, this was associated with a concomitant decrease in adenylate cyclase and increase in cAMP phosphodiesterase.¹⁹Many researchers in the field of plant biology have been unsuccessful in attempts to estimate the quantity of cAMP and to detect activities of adenylate cyclase and cAMP phosphodiesterase. On major difficulty is the presence of proteases and we have overcome this problem by using protease inhibitors, such as aprotinin and leupeptin.¹⁹In 1947, acetylcholine (ACh) of higher plants was first reported in a nettle (Urtica urens) found in the Himalaya mountain range.²⁰ In 1983, its existence in plants was confirmed by mass spectrometry of preparations from Vigna seedlings.²¹ In our preliminary studies, CCC (chlorocholinechloride), a plant growth retardant (specifically an anti-gibberellin), enhanced the elongation of the pollen tubes in pistils after self-incompatible pollination in lilies. This led us to investigate whether other choline derivatives cause similar effects and positive findings were obtained with ACh, acetylthiocholine and L-α-phosphatidlylcholine.²² Moreover, the elongation was also promoted by neostigmine, an inhibitor of acetylcholine esterase (AChE) activity. In line with these results, choline acetyltransferase (ChAT) demonstrated low and AChE high activity in pistils after self-incompatible pollination.The positive influence of cAMP^14,19 and ACh²² in pistils of L. longiflorum after self-incompatible pollination encouraged us to examine the involvement of these two molecules in regulation of pollen tube elongation of lily after self-incompatible and cross-compatible pollination. As a result, it was revealed that cAMP promotes ChAT and suppresses AChE activity in pistils after both self- and cross-pollination. In other words, the self-incompatibilty in pistils of L. longiflorum appears to be due to levels of ACh and/or cAMP below certain threshold values.Hitherto, these substances have not been recognized to play important roles in the metabolic systems of higher plants. However, given their conservation through evolution, it is natural that such central metabolic substances make essential contributions, regardless of the organism. We have succeeded in establishing physiological functions of cAMP and ACh in pistils of lily^14,19,22 and this points to use of plant reproductive organs such as research materials. The exact responsibilities of the two molecules may depend on differences in tissues or organs of plants and further molecular biological studies in this area are clearly warranted. This issue is currently being investigated.     

Biochemical characterization of photosystem I complexes having different subunit compositions of fucoxanthin chlorophyll a/c-binding proteins in the diatom Chaetoceros gracilis

Photosynthesis Research - Diatoms are dominant phytoplankton in aquatic environments and have unique light-harvesting apparatus, fucoxanthin chlorophyll a/c-binding protein (FCP). Diatom...