阅读说明：本技术 一种利用酰化淀粉定点释放短链脂肪酸的抗抑郁的方法 (Antidepressant method for releasing short-chain fatty acid at fixed point by using acylated starch ) 是由 王刚 朱慧越 王琳琳 田培郡 邹仁英 赵建新 张灏 陈卫 于 2020-07-31 设计创作，主要内容包括：本发明公开了一种利用酰化淀粉定点释放短链脂肪酸的抗抑郁的方法,属于酰化淀粉抗抑郁领域。本发明利用酰化淀粉作为短链脂肪酸的载体,模拟生理状态,在大肠内实现短链脂肪酸的定点释放,通过动物实验检测小鼠的抑郁表型、ACTH、CS与5-HT合成及转录等抑郁相关生理指标,筛选并确定了能够通过在小鼠肠道定点释放短链脂肪酸实现抗抑郁功能的酰化淀粉。本发明提供的酰化淀粉能够缓解抑郁小鼠的抑郁样行为、提高神经递质的合成水平、减轻压力导致的下丘脑-垂体-肾上腺轴功能亢进。利用本发明能够实现在肠道内定点释放短链脂肪酸,可作为一种靶向肠道内环境、成本更低、更安全有效的干预抑郁症的膳食方法。(The invention discloses an anti-depression method for releasing short-chain fatty acid at a fixed point by using acylated starch, belonging to the field of acylated starch anti-depression. The invention utilizes the acylated starch as a carrier of short-chain fatty acid to simulate physiological state, realizes the fixed-point release of the short-chain fatty acid in large intestine, detects depression phenotype, ACTH, CS, 5-HT synthesis, transcription and other depression related physiological indexes of a mouse through animal experiments, and screens and determines the acylated starch capable of realizing the antidepressant function by the fixed-point release of the short-chain fatty acid in the intestinal tract of the mouse. The acylated starch provided by the invention can relieve depression-like behaviors of depressed mice, improve synthesis level of neurotransmitter and relieve hyperthyroidism of hypothalamus-pituitary-adrenal axis caused by pressure. The invention can realize the fixed-point release of the short-chain fatty acid in the intestinal tract, and can be used as a dietary method for intervening depression with lower cost, higher safety and effectiveness by targeting the environment in the intestinal tract.)

1. The application of the acylated starch in the preparation of products for relieving and/or treating depression is characterized in that the acylated starch is obtained by replacing hydroxyl on D-glucopyranose of starch with acid anhydride, and the degree of substitution is within the range of 0.2-0.3.

2. Use according to claim 1, wherein the product is a medicament, a functional food, a food formulation for special medical use or a health product.

3. Use according to claim 1 or 2, wherein the alleviation and/or treatment of depression is embodied by at least one of (a) - (e):

(a) reducing the concentration of the hormones corticotropin and corticosterone with HPA hyperaxis;

(b) increasing the transcription level of colonic tryptophan hydroxylase Tph 1;

(c) improving the ability of the intestinal microorganisms to ferment protein foods to obtain tryptophan;

(d) the normal content of 5-hydroxytryptamine and the precursor substance thereof, namely 5-hydroxytryptamine, is recovered, and the anti-depression effect is realized;

(e) relieving depression, and improving anxiety accompanied with depression.

4. The use according to any one of claims 1 to 3, wherein the acylated starch is a mixture of one or more of acetylated starch, propionylated starch, isobutyrylated starch, butyrylated starch, and isovalerylated starch.

5. The use according to any one of claims 1 to 3, wherein the preparation method of the acylated starch comprises the following steps:

(1) continuously stirring 30-50% of starch milk at 30-45 ℃, and adjusting the pH of the starch milk to 7.5-8.5;

(2) dropwise adding acid anhydride accounting for 40-50% of the mass of the starch raw material into the reaction system in the step (1), controlling the temperature to be 30-45 ℃, and maintaining the pH value of the reaction system to be 7.5-8.5; after the dropwise addition of the acid anhydride is finished, continuously stirring and reacting for 1-3 h;

(3) and (3) adjusting the pH value of the solution after the reaction in the step (2) to 5.5-6.0, collecting the precipitate, washing, filtering, freezing and drying the precipitate to obtain the acylated starch.

6. An antidepressant drug is characterized in that the effective component of the drug is acylated starch; the degree of substitution of the acylated starch is between 0.2 and 0.3.

7. The medicament of claim 6, wherein the acylated starch is an acetylated starch, propionylated starch, isobutyrylated starch, butyrylated starch, or isovalerylated starch.

8. The medicament of claim 6, further comprising a pharmaceutically acceptable carrier.

9. The medicament according to any one of claims 6 to 8, wherein the medicament is in the form of an oral preparation.

10. Functional food or formula food for special medical use containing acylated starch.

Technical Field

The invention relates to an anti-depression method for releasing short-chain fatty acid at a fixed point by using acylated starch, belonging to the field of acylated starch anti-depression.

Background

Depression, also known as depressive disorder, has attracted widespread attention in various societies in recent years due to its rapidly increasing prevalence, disability rate, and suicide rate year after year. Depression is a common disorder of mental illness, often accompanied by anxiety symptoms, mainly including postpartum depression, major depression and bipolar disorder, with marked and persistent mood depression in the clinic. Depression impairs social cognitive ability, and while increasing physiological pain for patients, it also brings serious consequences such as disability and suicide, and threatens the harmonious stability and economic development of society. The pathogenesis of depression is not well defined and is generally considered to be related to the abnormality of the neurotransmitter 5-hydroxytryptamine.

The intestinal-brain axis is a two-way communication and regulation system, and the concept was originally proposed hundreds of years ago, and researchers published the idea that taking lactobacillus can help to treat melancholia. In recent years, researchers have come to recognize that intestinal microorganisms, intestinal mucosal barriers, blood-brain barriers, and the like are involved in the regulation of the "gut-brain axis". The gut flora not only regulates the function of the gut itself, but also communicates with the brain through a variety of pathways, including neural pathways, immune activation, and endocrine regulation. The research of the intestinal-cerebral axis opens up a new way for preventing and treating the depression by the hot tide. Research shows that the composition of intestinal flora of depression patients is obviously different from that of normal people, and the results show that the abundance of firmicutes bacteria is obviously reduced, people with intestinal microecology destroyed are more likely to have intestinal-cerebral axis functional disorder symptoms, the probability of cognitive behavior abnormality and depression symptoms after the infants use antibiotics is greatly improved, and the intestinal flora of the depression patients is transferred into sterile rats by a method of fecal bacteria transplantation to induce the rats to have anhedonia and depression-like behaviors. Therefore, the intestinal flora has the potential of remotely regulating and controlling the host nervous system, and the regulation and the recovery of the stability of the intestinal microecology are new means for preventing and treating depression and anxiety and are a new window for exploring the mysterious life of human beings.

The short-chain fatty acid as the most main metabolite of the intestinal flora can be used as an agonist of a G protein coupled receptor to mediate intestinal epithelial signals, can also be used as an inhibitor of histone deacetylase to play an important role, and has been the focus of research on life neuroscience. In the gastrointestinal tract, enteroendocrine cells line the lumen wall and respond to short chain fatty acids, releasing hormones, neurohormones, neurotransmitters, etc., sending signals systemically. The existing research shows that the tripodia-intestine-brain axis reduces the inflammation level, thereby improving the hyperthyroidism of the hypothalamus-pituitary-adrenal axis, and the intervention of neurotransmitter synthesis is probably a potential mechanism of relieving depression by short-chain fatty acid.

The currently reported methods for alleviating depression by short-chain fatty acids intervene by mixing sodium salts of short-chain fatty acids into the drinking water of mice. However, the use of sodium salts as antidepressant agents is deficient, is absorbed by the small intestine and does not explain the specific mechanism by which it acts. Therefore, there is a need to develop new methods for site-directed release of short chain fatty acids in the gastrointestinal tract.

Disclosure of Invention

In order to solve the technical problems, the invention provides the following technical scheme: a method for realizing an antidepressant function by releasing short-chain fatty acid in a mouse intestinal tract at a fixed point by using acylated starch comprises,

the first object of the present invention is to provide the use of acylated starch in the manufacture of a product for alleviating and/or treating depression.

In one embodiment, the alleviating and/or treating depression is embodied in at least one of (a) - (e):

(a) reducing the concentration of the hormones corticotropin and corticosterone with HPA hyperaxis;

(b) increasing the transcription level of colonic tryptophan hydroxylase Tph 1;

(c) improving the ability of the intestinal microorganisms to ferment protein foods to obtain tryptophan;

(d) the normal content of 5-hydroxytryptamine and the precursor substance thereof, namely 5-hydroxytryptamine, is recovered, and the anti-depression effect is realized;

(e) relieving depression, and improving anxiety accompanied with depression.

In one embodiment, the acylated starch has an anhydride substituted for hydroxyl groups on the D-glucopyranose of the starch with a degree of substitution in the range of 0.2 to 0.3.

In one embodiment, the product is a pharmaceutical, functional food, special medical use formula or health product.

In one embodiment, the starting material for the preparation of the acylated starch comprises high amylose corn starch.

In one embodiment, the acylated starch comprises an acetylated starch, a propionylated starch, an isobutyrylated starch, a butyrylated starch, or an isovalerylated starch.

In one embodiment, the acylated starch comprises an acetylated starch, butyrylated starch, or isobutyrylated starch.

In one embodiment, the method of preparing the acylated starch comprises the steps of:

(1) continuously stirring 30-50% of starch milk in mass fraction (w/w) at 30-45 ℃, and adjusting the pH of the starch milk to 7.5-8.5;

(2) dropwise adding acid anhydride accounting for 40-50% of the mass of the starch raw material into the reaction system in the step (1), controlling the temperature to be 30-45 ℃, and maintaining the pH value of the reaction system to be 7.5-8.5; after the dropwise addition of the acid anhydride is finished, continuously stirring and reacting for 1-3 h;

(3) and (3) adjusting the pH value of the solution after the reaction in the step (2) to 5.5-6.0, collecting the precipitate, washing, filtering, freezing and drying the precipitate to obtain the acylated starch.

In one embodiment, the freeze drying is pre-freezing at-50 deg.C under 200 μ bar vacuum for 4h, primary drying at-30 deg.C under 200 μ bar vacuum for 32h, secondary drying at 25 deg.C under 0 μ bar vacuum for 24h, and cold trapping at-80 deg.C.

In one embodiment, the preparation method of the acylated starch is specifically as follows: preparing starch and distilled water into starch milk with the mass fraction (w/w) of 40%, adding into a stirring rotor, and uniformly mixing on a thermal magnetic stirrer at normal temperature; controlling the temperature of the stirrer to be 40 ℃, continuously stirring, and adjusting the system of the starch emulsion to pH 8.00 by using 0.50mol/L sodium hydroxide solution; dripping anhydride within 1.5h, wherein the dripping amount is 50 percent of the mass of the starch raw material, controlling the temperature to be 40 ℃, and adding a sodium hydroxide solution to maintain the pH of the reaction system to be about 8.00; after the dropwise addition of the acid anhydride is finished, continuously stirring and reacting for 2 hours; after the reaction is finished, adjusting the pH value of the system to about 5.70 by using 0.50mol/L hydrochloric acid; settling, pouring out supernatant, adding 500mL of water into the precipitate, washing, and performing suction filtration under 20KPa negative pressure for 5-10 min; repeating the steps for washing for 3-5 times, washing with water until the washing liquid is neutral, and collecting the precipitate into a glass dish; and (5) freezing and drying to obtain the acylated starch. The conditions for freeze-drying were: pre-freezing at-50 deg.C under 200 μ bar vacuum for 4 hr, primary drying at-30 deg.C under 200 μ bar vacuum for 32 hr, secondary drying at 25 deg.C under 0 μ bar vacuum for 24 hr, and cold trapping at-80 deg.C.

In one embodiment, the acylated starch is ingested in a daily amount of 1 to 5mmol of acylated starch per kg of body weight.

The second purpose of the invention is to provide an antidepressant drug, and the effective component of the drug is the acylated starch.

In one embodiment, the degree of substitution of the acylated starch is in the range of 0.2 to 0.3 and the release of short chain fatty acids in the large intestine is increased to more than 10 times that in the small intestine.

In one embodiment, the medicament further comprises a pharmaceutically acceptable carrier.

Functional foods or formulations for specific medical uses containing said acylated starch are also claimed.

The invention has the beneficial effects that: the invention adopts the acylated starch as the carrier of the short-chain fatty acid, and animal experiments prove that the acylated starch can resist the hydrolysis of small intestine enzyme and decompose and release the short-chain fatty acid in the large intestine by microorganisms, thereby improving the depression behavior phenotype of mice, relieving the physiological indexes related to depression, such as reducing the concentration of hormone adrenocorticotropic hormone and corticosterone with hyperparathyroidism of HPA axis, improving the transcription level of Tph1, improving the capability of obtaining tryptophan by fermenting protein foods by intestinal microorganisms, recovering the normal content of 5-hydroxytryptamine and the precursor substance thereof, and realizing the anti-depression effect.

The invention utilizes good carrier (acylated starch) of short-chain fatty acid, and verifies the effectiveness of the method for realizing antidepressant by releasing the short-chain fatty acid at a fixed point through the acylated starch in animal experiments through chronic unpredictable stress molding mice. The invention provides a method for realizing an antidepressant function by releasing short-chain fatty acid at a fixed point in an intestinal tract of a mouse by using acylated starch.

Drawings

FIG. 1 is a schematic diagram of chromatographic retention times for SCFAs; in this case, the horizontal axis represents time, and the vertical axis represents Relative abundance (Relative abundance).

FIG. 2 is a graph showing the major SCFAs content in different intestine segments of a mouse 5 weeks after acylated starch intervention in depressed mice; (a) small intestine portion acetic acid, propionic acid and butyric acid concentrations; (b) caecum fraction acetic, propionic, and butyric acid concentrations.

FIG. 3 is a schematic representation of the behavioral changes of groups of mice 5 weeks after acylated starch intervention in depressed mice; (a) open field experiments (first incubation period); (b) open field test (center area movement distance); (c) elevated plus maze experiments; (d) forced swimming experiment; wherein^#P<0.05，^##P<0.01(vs blank); p<0.05，**P<0.01，***P<0.001(vs model group).

FIG. 4 is a graph showing the change of the serum adrenocorticotropic hormone ACTH (a) and the serum corticosterone CS (b) levels in the serum of each group of mice 5 weeks after the acylated starch intervention in depressed mice; wherein^##P<0.01(vs blank); p<0.05(vs model group). times.P<0.01(vs model set).

FIG. 5 is a graph showing the level of Tph1mRNA in colon tissue of mice 5 weeks after acylated starch intervention in depressed mice; wherein^#P<0.05(vs blank); p<0.05(vs control group))。

FIG. 6 is a graph showing 5 weeks after acylated starch intervention in depressed mice, the levels of 5-HT and its precursors in colon tissues of mice; (a) tryptophan levels; (b) 5-hydroxytryptophan concentration; (c) 5-hydroxytryptamine concentration; wherein^#P<0.05(vs blank); p<0.05，**P<0.01，***P<0.001，****P<0.0001(vs model set).

FIG. 7 is a graph (a) of orthogonal partial least squares discriminant analysis (OPLS-DA) and a graph (b) of PCA loading made for the results of a combination of behavioral testing and correlation with physiological indices in mice.

FIG. 8 is a schematic diagram showing the behavioral changes of mice in each group 5 weeks after gavage short-chain fatty acid intervention in depressed mice; (a) open field experiments (first incubation period); (b) open field test (center area shift distance).

FIG. 9 is a schematic diagram showing the behavioral changes of mice in each group 5 weeks after the addition of sodium acid salt to drinking water to intervene in depressed mice; (a) open field experiments (first incubation period); (b) open field test (center area movement distance); wherein^###P<0.01(vs blank).

Detailed Description