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Lipotoxicity has been shown to cause dysfunction of many organs and tissues. However, it is unclear whether lipotoxicity is harmful to the somatotrophs, a kind of cell that synthesize growth hormone (GH) in the pituitary. In this study, we performed an epidemiological study, serum levels of triglyceride (TG) and GH showed a negative correlation, even after adjustment for potential confounders. In an animal study, male Sprague‐Dawley rats were fed a high‐fat diet (HFD) or a control diet for 28 weeks. HFD rats showed impaired GH synthesis, resulting in a decrease in circulating GH levels. The expression of pituitary Pit‐1, a key transcription factor of GH, was inhibited. We found that the inositol‐requiring enzyme 1α (IRE1α) pathway of endoplasmic reticulum (ER) stress was triggered in HFD rat pituitary glands and palmitic acid‐treated GH3 cells, respectively. On the contrary, applying 4‐phenyl butyric acid (4‐PBA) to alleviate ER stress or 4µ8c to specifically block the IRE1α pathway attenuated the impairment of both Pit‐1 and GH expression. In conclusion, we demonstrated that lipotoxicity directly inhibits the synthesis of GH, probably by reducing Pit‐1 expression. The IRE1α signaling pathway of ER stress may play an important role in this process.

Emerging epidemiological studies indicate that hypercholesterolaemia is a risk factor for testosterone deficiency. However, the underlying mechanism is unclear. Testicular Leydig cells are the primary source of testosterone in males. To identify the effect and mechanism of cholesterol overload on Leydig cell function, rats were fed with a HC (HC) diet to induce hypercholesterolaemia. During the 16‐week feeding period, serum testosterone levels were reduced in a time‐dependent manner in rats fed the HC diet. Accordingly, these steroidogenic enzymes within the Leydig cells, including steroidogenic acute regulatory protein (StAR), cholesterol side‐chain cleavage cytochrome P450 (P450scc) and 3β‐hydroxysteroid dehydrogenase (3β‐HSD), were down‐regulated. Notably, the HC‐fed rats showed evident endoplasmic reticulum (ER) stress in the testis, including a dilated ER as an evident pathological change in the Leydig cell ultrastructure, up‐regulated ER stress biomarker (binding immunoglobulin protein) levels and activation of the activating transcription factor 6 (ATF6)‐related unfolded protein response pathway. Further analysis showed that when 4‐phenyl butyric acid (4‐PBA) was used to block ER stress in HC‐fed rats for 8 weeks, the testosterone deficiency was significantly alleviated. Our findings suggested that high dietary cholesterol intake affected serum testosterone levels by down‐regulating steroidogenic enzymes and that activated ER stress might serve as the underlying mechanism.

Coke deposition is the biggest barrier that hinders the hydrocarbon yields during the catalytic pyrolysis of biomass. The proposed pathway studied here yields benzofuran as a primary product, all the olefins and aromatic hydrocarbons as secondary products, and polycyclic aromatic hydrocarbons as tertiary products. The product selectivity only changed with catalytic temperature and coke deposition, whereas no effect was observed if the weight hourly space velocity and partial pressure were varied. The curve of conversion versus coke content in the catalytic conversion of furan follows an exponential trend [i.e., Φ=exp(-αC)] which indicates that the catalytic conversion of furan exhibits fast deactivation. A kinetic model considering coke deposition has been built based on the above reaction pathway to correlate the product distribution with the coke content, and the final correlation coefficients (>0.96) indicate good agreement.

Barley flour is widely utilized in food and nonfood industries. Morphological, structural, and functional properties of starches extracted from waxy and non‐waxy barley are investigated and compared in this work. The morphology of starch granules in waxy and non‐waxy barley is similar while waxy barley has a higher proportion of A‐type starch granules and a lower proportion of B‐type starch granules than those of non‐waxy barley. Compared with non‐waxy barley starch, waxy barley starch shows higher amylopectin content with higher levels of amylopectin short and long branch‐chains; better ordered structures with higher relative crystallinity, IR ratio of 1045/1022 cm⁻¹, and a double helical component, a lower amorphous and V‐type single helix components. The gelatinization temperature and enthalpy of waxy barley starch are higher than those of non‐waxy barley starch. Meanwhile, waxy barley starch presents higher swelling power, solubility, pasting viscosities, breakdown value, and lower setback value than those of non‐waxy barley starch. Furthermore, waxy barley starch is more susceptible to acid and enzymatic hydrolysis than non‐waxy barley starch. Results indicate that waxy and non‐waxy barley starches differ in physicochemical properties, and waxy barley may have a better mouthfeel and edible quality.

Lilium lancifolium is an important edible starch plant that is widely cultivated in China. Bulbs and bulbils are starch storage organs of L. lancifolium found below and above ground. To further utilize lily starch resources, starches were extracted from bulbs and bulbils of L. lancifolium. The morphological, structural, thermal, hydrolytic, and in vitro digestive properties of these starches were systematically investigated and compared. The bulb and bulbil starches differed in their amylose content and granule size, as well as their shape and surface morphologies. Compared with bulbil starch, bulb starch had a relatively higher degree of crystallinity. The ordered structure in the external granule region of bulb starch was similar to that of bulbil starch. In addition, bulb starch demonstrated significantly higher solubility, onset temperature, and gelatinization enthalpy than bulbil starch. When hydrolyzed by α-amylase and hydrochloric acid, bulb starch exhibited stronger resistance to enzymolysis but had a higher degree of acidolysis than bulbil starch. In vitro digestion showed that native and gelatinized bulb starches contained lower slowly digestible starch (SDS) content and higher resistant starch (RS) content than bulbil starch. In retrograded starch, bulbs and bulbils had similar amounts of rapidly digestible starch, SDS, and RS. This study sufficiently described the morphological and physicochemical properties of bulb and bulbil starches from L. lancifolium. This information is crucial to the future application of these starches in the food and nonfood industries.

Emerging evidence shows that elevated cholesterol levels are detrimental to health. However, it is unclear whether there is an association between cholesterol and the pituitary. We investigated the effects of a high-cholesterol diet on pituitary hormones using in vivo animal studies and an epidemiological study. In the animal experiments, rats were fed a high-cholesterol or control diet for 28 weeks. In rats fed the high-cholesterol diet, serum levels of thyroid-stimulating hormone (TSH; also known as thyrotrophin), luteinising hormone (LH) and follicle-stimulating hormone (FSH) produced by the basophilic cells of the anterior pituitary were elevated in a time-dependent manner. Among these hormones, TSH was the first to undergo a significant change, whereas adrenocorticotrophic hormone (ACTH), another hormone produced by basophilic cells, was not changed significantly. As the duration of cholesterol feeding increased, cholesterol deposition increased gradually in the pituitary. Histologically, basophilic cells, and especially thyrotrophs and gonadotrophs, showed an obvious increase in cell area, as well as a potential increase in their proportion of total pituitary cells. Expression of the β-subunit of TSH, FSH and LH, which controls hormone specificity and activity, exhibited a corresponding increase. In the epidemiological study, we found a similar elevation of serum TSH, LH and FSH and a decrease in ACTH in patients with hypercholesterolaemia. Significant positive correlations existed between serum total cholesterol and TSH, FSH or LH, even after adjusting for confounding factors. Taken together, the results of the present study suggest that the high-cholesterol diet affected the levels of hormones derived from anterior pituitary basophilic cells. This phenomenon might contribute to the pituitary functional disturbances described in hypercholesterolaemia.

DYX1C1 and KIAA0319 have been two of the most extensively studied candidate genes for dyslexia given their important roles in the neuronal migration and neurite growth. The −3G > A in DYX1C1 and the 931C > T in KIAA0319 were of special interest for dyslexia but with inconsistent results. We performed a meta-analysis integrating case–control and transmission/disequilibrium test (TDT) studies to clearly discern the effect of these two variants in dyslexia. Data from case–control and TDT studies were analyzed in an allelic model using the Catmap software. In overall meta-analysis, the pooled OR for the −3A allele and the 931T allele was 0.68 (95% CI = 0.25–1.87, Pheterogeneity = 0.000) and 0.87 (95% CI = 0.78–0.98, Pheterogeneity = 0.125), respectively. The stratified analysis showed that the between-study heterogeneity regarding the −3G > A polymorphism might be accounted by the publication year. Additionally, the sensitivity analysis of −3G > A polymorphism indicated the stability of the result. In conclusion, our results suggested that the 931C > T variant in KIAA0319, but not the −3G > A in DYX1C1, was significantly associated with the risk of dyslexia. © 2012 Wiley Periodicals, Inc.

Scope Increasing evidence has shown that the disturbance of lipid metabolism might make a possible contribution to the pathogenesis of organ dysfunction, including thyroid, yet it is unknown whether excess intake of dietary fat interferes in thyroid lipid profile. We investigate the effects of dietary fat toward the thyroid lipid profile and thyroid function. Methods and results Male Sprague-Dawley rats are fed with high-fat diet (HFD) rich in saturated and mono-unsaturated fatty acids or chow diet for 18 weeks. LC-MS analysis of thyroid shows that total free fatty acids (FFAs) content is significantly higher in HFD rats. The concentration of highly saturated triglycerides significantly increases in HFD rats, whereas the polyunsaturated triglyceride significantly decreases, indicating the decrease in unsaturation in the HFD group. Significant increase of lysophosphatidylcholines (LPC) is observed in HFD rats. Thyroid function tests show hypothyroxinemia (total thyroxine [TT4 ] and free thyroxine [FT4 ]) in HFD rats, and elevated thyrotropin (TSH) concentration. The HFD rats also show decreased thyroid uptake of iodine. Conclusion Excess intake of dietary fat induces disturbance of thyroid lipid profile and hypothyroxinemia, indicating thyroid dysfunction. We speculate that it may provide a new prospect in understanding the pathogenesis of hypothyroidism.