CN-122005837-A - Sugar-responsive protamine insulin and preparation method and application thereof

Abstract

The invention relates to a preparation method and application of sugar-responsive protamine insulin, which is characterized in that chemical groups are modified on cysteine of protamine, and is connected with phenylboronic acid compounds to form a compound, and then is mixed with insulin to prepare the sugar-responsive protamine insulin. Such sugar-responsive insulin formulations are capable of achieving a smart sugar response modulation mechanism. Specifically, under normal blood sugar level, the insulin is slowly released, and under high blood sugar state, the release is accelerated, so that effective regulation and control of blood sugar are realized, and occurrence of hypoglycemia is avoided.

Inventors

• GU ZHEN
• LIU WEI
• WANG JINQIANG

Assignees

• 浙江大学

Dates

Publication Date

20260512

Application Date

20240807

Priority Date

20230807

Claims (10)

1. 1. A sugar-responsive insulin carrier comprising a protamine and a phenylboronic acid compound, wherein the cysteine in the protamine is directly or indirectly linked to the phenylboronic acid compound, or the phenylboronic acid compound directly or indirectly modifies the cysteine in the protamine.
2. 2. The vector of claim 1, wherein the cysteines in the protamine are modified with chemical groups that are linked to NHS esterified phenylboronic acids via chemical bonds.
3. 3. The carrier according to claim 2, wherein the chemical group is connected with protamine in a thioether bond, and the chemical bond between the chemical group and the NHS esterified phenylboronic acid compound is an amide bond.
4. 4. The carrier of claim 2, wherein the chemical groups comprise any one or more of a linear or branched alkyl, hydroxy, carboxyl, amino, or mercapto group, or any one or more of an alkyl, hydroxy, carboxyl, amino, or mercapto group substituted at any position of these groups.
5. 5. The carrier of claim 4, wherein the chemical group has a structural formula comprising any one or more of formulas I-IV: Formula I and formula II Formula III Formula IV.
6. 6. The carrier according to claim 5, wherein the phenylboronic acid compound comprises phenylboronic acid modified by different groups, and the modified groups comprise one or more of alkyl, carboxyl, halogen, nitro and amide.
7. 7. A method of preparing a sugar-responsive insulin carrier comprising the steps of: reacting the compound solution with a protamine solution to obtain a solution A; Reacting the solution A with NHS esterified phenylboronic acid compound solution; The structural formula of the compound comprises any one or more of the formulas I-IV: Formula I and formula II Formula III formula IV.
8. 8. The method according to claim 7, wherein the molar ratio of the compound in the step (1) to protamine is 1 to 50:1.
9. 9. A sugar-responsive protamine insulin complex prepared by mixing the carrier of any one of claims 1-6 with insulin.
10. 10. A method for preparing a sugar-responsive protamine insulin complex, characterized in that the sugar-responsive insulin carrier according to any one of claims 1 to 6 is mixed with insulin, and the pH is adjusted to 6.5 to 8.0, to obtain the sugar-responsive protamine insulin complex.

Description

Sugar-responsive protamine insulin and preparation method and application thereof The present application is a divisional application of the parent application 2024110785276. The application claims priority to China prior application number 202310987884.3, application day 2023, 8, 7, the description, claims, abstract and drawings set forth this application as part of the application in its entirety. Technical Field The invention belongs to the technical field of drug delivery, and particularly relates to a sugar-responsive protamine insulin, and a preparation method and application thereof. Background Currently, diabetes affects more than 5.37 million people worldwide, and it is expected that 2045 years of illness will exceed 7.83 million people. Diabetes is a common chronic disease, and is characterized by abnormal glucose metabolism caused by absolute or relative insulin secretion, and is mainly clinical manifestation of hyperglycemia. Diabetes mellitus is largely divided into two major categories, type I diabetes mellitus (T1 DM) and type II diabetes mellitus (T2 DM). Among them, T1DM is mainly caused by the damage of insulin-secreting islet beta cells in patients, and is of minor age in onset and is manifested by absolute deficiency of insulin. T2DM is mainly caused by insulin resistance, and is frequently found in the elderly, and is manifested by a relative deficiency of insulin. T1DM and late T2DM require daily injections or continuous infusions of exogenous insulin to maintain blood glucose levels within normal ranges. In order to reduce the frequency of daily insulin injections, the 1936 long-acting insulin preparation, zinc protamine insulin (PZI), was born. Insulin in PZI can form a complex with excessive protamine and zinc, so that the stability of the preparation is improved, the release of insulin in the body is delayed, and the acting time of insulin is prolonged. In 1946, neutral protamine zinc insulin (NPH) with more stable properties was developed successfully, and NPH is mainly used for providing basic insulin, and can control blood sugar before two meals and at night to keep stable. Since exogenous insulin is not regulated by endogenous feedback mechanisms, diabetics may inevitably experience symptoms of hyperglycemia or hypoglycemia even with well-designed dosage regimens, even where the patient strictly follows the prescribed diet and lifestyle. Thus, a glucose responsive insulin system that mimics the mechanism of endogenous insulin action is critical and provides a therapeutic approach that adjusts insulin release rate in real time to the patient's blood glucose level, thereby improving therapeutic efficacy and reducing adverse effects. Currently, glucose responsive elements for modifying insulin mainly include glucose oxidase (GO X), phenylboronic acid (pH enylboronic acid, PBA) and glucose-binding molecules. In the prior art, phenylboronic acid or a phenylboronic acid derivative is compounded with a polymer to prepare an insulin delivery carrier, such as a patent CN115671050A, a polyacrylic carbonate-polycaprolactone is taken as a raw material, the phenylboronic acid derivative and a dihydroxyl form a phenylboronic acid ester compound, a liver-targeted glucose responsive nanoparticle is prepared by a W/O/W emulsion method and an ultraviolet crosslinking technology, and based on the above strategy, a PBA group modified poly N- (2-aminoethyl) acrylamide is prepared by a researcher, and insulin is loaded by using the material, so that the insulin delivery carrier has a glucose response performance and a glucose control effect in animals. However, the polymer materials are adopted in the research preparation, the preparation process is complicated, and the biocompatibility and safety of the polymer are also lack of clinical verification. Compared with the polymer, the protamine has better biocompatibility and safety, and no related report of protamine insulin with sugar responsiveness exists at present. Disclosure of Invention The invention provides a sugar-responsive protamine insulin, a preparation method and application thereof, which aim to solve the problem of low blood sugar which is difficult to avoid in a protamine insulin system in the prior art, and the sugar-responsive protamine insulin is prepared by modifying a chemical group on protamine cysteine, connecting the chemical group with phenylboronic acid compounds to form a compound and mixing the compound with insulin. In one aspect, the invention provides a sugar-responsive insulin carrier comprising protamine and a phenylboronic acid compound, wherein cysteine in the protamine is directly or indirectly linked to the phenylboronic acid compound, or the phenylboronic acid compound directly or indirectly modifies the cysteine. Protamine is a mixture of strongly basic peptides which was originally isolated from salmon and other species of fish sperm, but is now produced recombinantly, primarily by biotechnology, and which cont