Biosynthetic Human Insulin and Insulin Analogs

Peptides as Therapeutic Agents: Challenges and Opportunities in the Green Transition Era

Peptides are at the cutting edge of contemporary research for new potent, selective, and safe therapeutical agents. Their rise has reshaped the pharmaceutical landscape, providing solutions to challenges that traditional small molecules often cannot address. A wide variety of natural and modified peptides have been obtained and studied, and many others are advancing in clinical trials, covering multiple therapeutic areas. As the demand for peptide-based therapies grows, so does the need for sustainable and environmentally friendly synthesis methods. Traditional peptide synthesis, while effective, often involves environmentally draining processes, generating significant waste and consuming vast resources. The integration of green chemistry offers sustainable alternatives, prioritizing eco-friendly processes, waste reduction, and energy conservation. This review delves into the transformative potential of applying green chemistry principles to peptide synthesis by discussing relevant examples of the application of such approaches to the production of active pharmaceutical ingredients (APIs) with a peptide structure and how these efforts are critical for an effective green transition era in the pharmaceutical field.

Type 1 Diabetes Overview and Perioperative Management

Type 1 diabetes (T1D) is an increasingly common condition. Although often more effective, treatment regimens for patients with T1D have become more variable and complex with newer insulin analogues and increasing use of diabetes technology. Both surgery and anesthesia are known to trigger a stress response that causes dramatic metabolic changes in the patient that tend to increase glucose variability. Close monitoring of glucose levels and clear algorithms for insulin administration can ameliorate these characteristic responses. As T1D treatment technology becomes more effective at maintaining glucose in target range, there should be more consideration of using this technology during hospitalization and surgery.

Spectro-spatial features in distributed human intracranial activity proactively encode peripheral metabolic activity

Mounting evidence demonstrates that the central nervous system (CNS) orchestrates glucose homeostasis by sensing glucose and modulating peripheral metabolism. Glucose responsive neuronal populations have been identified in the hypothalamus and several corticolimbic regions. However, how these CNS gluco-regulatory regions modulate peripheral glucose levels is not well understood. To better understand this process, we simultaneously measured interstitial glucose concentrations and local field potentials in 3 human subjects from cortical and subcortical regions, including the hypothalamus in one subject. Correlations between high frequency activity (HFA, 70-170 Hz) and peripheral glucose levels are found across multiple brain regions, notably in the hypothalamus, with correlation magnitude modulated by sleep-wake cycles, circadian coupling, and hypothalamic connectivity. Correlations are further present between non-circadian (ultradian) HFA and glucose levels which are higher during awake periods. Spectro-spatial features of neural activity enable decoding of peripheral glucose levels both in the present and up to hours in the future. Our findings demonstrate proactive encoding of homeostatic glucose dynamics by the CNS.

Generation of a Beta-Cell Transplant Animal Model of Diabetes Using CRISPR Technology

Since insulin deficiency results from pancreatic beta-cell destruction, all type 1 and most type 2 diabetes patients eventually require life-long insulin injections. Insulin gene synthesis could also be impaired due to insulin gene mutations as observed in diabetic patients with MODY 10. At this point, insulin gene therapy could be very effective to recompense insulin deficiency under these circumstances. For this reason, an HIV-based lentiviral vector carrying the insulin gene under the control of insulin promoter (LentiINS) was generated, and its therapeutic efficacy was tested in a beta-cell transplant model lacking insulin produced by CRISPR/Cas9-mediated genetically engineered pancreatic beta cells. To generate an insulin knockout beta-cell transplant animal model of diabetes, a dual gene knockout plasmid system involving CRISPR/Cas9 was transfected into a mouse pancreatic beta cell line (Min6). Fluorescence microscopy and antibiotic selection were utilized to select the insulin gene knockout clones. Transplantation of the genetically engineered pancreatic beta cells under the kidney capsule of STZ-induced diabetic rats revealed LentiINS- but not LentiLacZ-infected Ins2KO cells transiently reduced hyperglycemia similar to that of MIN6 in diabetic animals. These results suggest LentiINS has the potential to functionally restore insulin production in an insulin knockout beta-cell transplant animal model of diabetes.

Current Insights on the Use of Insulin and the Potential Use of Insulin Mimetics in Targeting Insulin Signalling in Alzheimer's Disease

Alzheimer's disease (AD) and type 2 diabetes (T2D) are chronic diseases that share several pathological mechanisms, including insulin resistance and impaired insulin signalling. Their shared features have prompted the evaluation of the drugs used to manage diabetes for the treatment of AD. Insulin delivery itself has been utilized, with promising effects, in improving cognition and reducing AD related neuropathology. The most recent clinical trial involving intranasal insulin reported no slowing of cognitive decline; however, several factors may have impacted the trial outcomes. Long-acting and rapid-acting insulin analogues have also been evaluated within the context of AD with a lack of consistent outcomes. This narrative review provided insight into how targeting insulin signalling in the brain has potential as a therapeutic target for AD and provided a detailed update on the efficacy of insulin, its analogues and the outcomes of human clinical trials. We also discussed the current evidence that warrants the further investigation of the use of the mimetics of insulin for AD. These small molecules may provide a modifiable alternative to insulin, aiding in developing drugs that selectively target insulin signalling in the brain with the aim to attenuate cognitive dysfunction and AD pathologies.

Analysis of curative effect of insulin external application on burn wounds of diabetic patients with different depths

To explore the curative effect of insulin external application on burn wounds of diabetic patients with different depths. A retrospective analysis of 114 diabetic burn patients in the First Hospital of Hebei Medical University from June 2019 to June 2022. According to the different treatment methods, they were divided into study group (insulin therapy) and control group (conventional therapy) with 57 cases in each. The wound healing time, dressing changes, scar healing after wound healing and adverse events were compared between two groups. Pain level, serum inflammatory factors, vascular endothelial growth factor (VEGF) and oxidative stress factors before and after treatment were compared. The wound healing time (17.23 ± 2.18 vs 20.31 ± 2.09 days) and the number of dressing changes (7.01 ± 1.23 vs 8.93 ± 1.32 times) in study group were significantly lower than those in control group (P < 0.05). Before treatment, there was no difference in pain level, VEGF, interleukin-1 (IL-1), tumour necrosis factor-α (TNF-α), malondialdehyde (MDA) and superoxide dismutase (SOD) between two groups (P > 0.05). However, the pain level, scar healing, IL-1, TNF-a and MDA in study group were significantly lower than those in control group after treatment (P < 0.05). And the VEGF and SOD in study group was significantly higher than that in control group (P < 0.05). External application of insulin can shorten the wound healing time of diabetic patients with different depths, reduce the number of dressing changes, promote scar healing after wound healing, relieve pain and reduce the level of inflammatory factors, which is worthy of clinical promotion.

An Investigation into the Correlation of Intestinal Flora with Obesity and Gestational Diabetes Mellitus

Method

Thirty-two pregnant women aged 25-35 who were hospitalized in Shanxi Maternal and Child Health Hospital from January 2019 to December 2019 were included for evaluation, including 15 normal pregnant women (NG_NO group), 6 pregnant women with GDM alone (G_NO group), and 7 pregnant women with overweight alone (NG_O group). Stools were collected from pregnant women at 24 and 37 weeks of gestation and newborns' first meconium. The v3-v4 variable region of the gut flora 16s rRNA was double-ended sequenced and bioinformatically analyzed using the Illumina MiSeq PE300 sequencing platform.

Results

In the third trimester of pregnancy, there were significant differences in the composition of intestinal flora between the simple overweight group, simple GDM group, and normal pregnant group. From the second trimester to the third trimester, there was no significant change in the relative distribution of intestinal flora at the phyla classification level in normal pregnant women. The relative distribution of intestinal flora at the phylum level of newborns was significantly different from that of their mothers. The characteristic intestinal microbes of newborns in simple GDM group were g_Diaphorobacter, while the simple recombinant neonates were Nocardiaceae (f_Nocardioidaceae). In addition, the results showed significant differences in intestinal flora among the normal pregnant women group, simple GDM group, simple overweight group, and GDM overweight group. The results of β diversity analysis showed a significant difference in intestinal microflora species composition structure between the simple overweight group and the normal pregnant group in the second trimester of pregnancy. The species composition structure of intestinal flora was similar between the simple GDM group and the normal pregnant group. In the third trimester of pregnancy, there was no significant difference in the β diversity index among the groups, and the composition and structure of intestinal flora were similar. There were significant differences in the composition structure (β diversity) of intestinal flora between pregnant women and their newborns in each group (P < 0.05). Correlation analysis showed that the blood glucose values of oral glucose tolerance test (OGTT)_1 h and OGTT_2 h were positively correlated with Bacteroides (Bacteroides) and negatively correlated with Proteus (Prevotella), prepregnancy BMI was negatively correlated with Bacteroides, and weight gain during pregnancy was negatively correlated with Vibrio (Desulfovibrio) in Proteus. The birth weight of newborns was positively correlated with Actinomycetes (Actinomyces), Bacteroides (Faecalibacterium), and microbacilli (Dialister) and negatively correlated with Rolston (Ralstonia).

Conclusion

Gut microbiota is strongly linked to obesity and gestational diabetes.

The Other Face of Insulin—Overdose and Its Effects

Insulin is the most effective glycemic-lowering drug, and for people suffering from type 1 diabetes it is a life-saving drug. Its self-dosing by patients may be associated with a higher risk of overdose, both accidental and deliberate. Insulin-induced hypoglycemia causes up to 100,000 emergency department calls per year. Cases of suicide attempts using insulin have been described in the literature since its introduction into therapy, and one of the important factors in their occurrence is the very fact of chronic disease. Up to 90% of patients who go to toxicology wards overdose insulin consciously. Patients with diabetes are burdened with a 2–3 times higher risk of developing depression compared to the general population. For this reason, it is necessary to develop an effective system for detecting a predisposition to overdose, including the assessment of the first symptoms of depression in patients with diabetes. A key role is played by a risk-conscious therapeutic team, as well as education. Further post-mortem testing is also needed for material collection and storage, as well as standardization of analytical methods and interpretation of results, which would allow for more effective detection and analysis of intentional overdose—both by the patient and for criminal purposes.

Proteomic Changes to the Updated Discovery of Engineered Insulin and Its Analogs: Pros and Cons

The destruction of β-cells of the pancreas leads to either insulin shortage or the complete absence of insulin, which in turn causes diabetes Mellitus. For treating diabetes, many trials have been conducted since the 19th century until now. In ancient times, insulin from an animal's extract was taken to treat human beings. However, this resulted in some serious allergic reactions. Therefore, scientists and researchers have tried their best to find alternative ways for managing diabetes with progressive advancements in biotechnology. However, a lot of research trials have been conducted, and they discovered more progressed strategies and approaches to treat type I and II diabetes with satisfaction. Still, investigators are finding more appropriate ways to treat diabetes accurately. They formulated insulin analogs that mimic the naturally produced human insulin through recombinant DNA technology and devised many methods for appropriate delivery of insulin. This review will address the following questions: What is insulin preparation? How were these devised and what are the impacts (both positive and negative) of such insulin analogs against TIDM (type-I diabetes mellitus) and TIIDM (type-II diabetes mellitus)? This review article will also demonstrate approaches for the delivery of insulin analogs into the human body and some future directions for further improvement of insulin treatment.

Progress in Simulation Studies of Insulin Structure and Function

Insulin is a peptide hormone known for chiefly regulating glucose level in blood among several other metabolic processes. Insulin remains the most effective drug for treating diabetes mellitus. Insulin is synthesized in the pancreatic β-cells where it exists in a compact hexameric architecture although its biologically active form is monomeric. Insulin exhibits a sequence of conformational variations during the transition from the hexamer state to its biologically-active monomer state. The structural transitions and the mechanism of action of insulin have been investigated using several experimental and computational methods. This review primarily highlights the contributions of molecular dynamics (MD) simulations in elucidating the atomic-level details of conformational dynamics in insulin, where the structure of the hormone has been probed as a monomer, dimer, and hexamer. The effect of solvent, pH, temperature, and pressure have been probed at the microscopic scale. Given the focus of this review on the structure of the hormone, simulation studies involving interactions between the hormone and its receptor are only briefly highlighted, and studies on other related peptides (e.g., insulin-like growth factors) are not discussed. However, the review highlights conformational dynamics underlying the activities of reported insulin analogs and mimetics. The future prospects for computational methods in developing promising synthetic insulin analogs are also briefly highlighted.

Novel glucose-responsive nanoparticles based on p-hydroxyphenethyl anisate and 3-acrylamidophenylboronic acid reduce blood glucose and ameliorate diabetic nephropathy

An insulin delivery system that self-regulates blood sugar levels, mimicking the human pancreas, can improve hyperglycaemia. At present, a glucose-responsive insulin delivery system combining AAPBA with long-acting slow release biomaterials has been developed. However, the safety of sustained-release materials and the challenges of preventing diabetic complications remain. In this study, we developed a novel polymer slow release material using a plant extract—p-hydroxyphenylethyl anisate (HPA). After block copolymerisation with AAPBA, the prepared nanoparticles had good pH sensitivity, glucose sensitivity, insulin loading rate and stability under physiological conditions and had high biocompatibility. The analysis of streptozotocin-induced diabetic nephropathy (DN) mouse model showed that the insulin-loaded injection of nanoparticles stably regulated the blood glucose levels of DN mice within 48 ​h. Importantly, with the degradation of the slow release material HPA in vivo, the renal function improved, the inflammatory response reduced, and antioxidation levels in DN mice improved. This new type of nanoparticles provides a new idea for hypoglycaemic nano-drug delivery system and may have potential in the prevention and treatment of diabetic complications.

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We established a new glucose-responsive intelligent system with HPA.

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p(AAPBA-b-HPA) shows good pH and glucose sensitivity.

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p(AAPBA-b-HPA) nanoparticles can slowly release HPA and insulin.

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This system can be used to regulate blood glucose.

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p(AAPBA-b-HPA) nanoparticles can aid in diabetic nephropathy prevention and treatment.

Type 1 diabetes glycemic management: Insulin therapy, glucose monitoring, and automation

Despite innovations in insulin therapy since its discovery, most patients living with type 1 diabetes do not achieve sufficient glycemic control to prevent complications, and they experience hypoglycemia, weight gain, and major self-care burden. Promising pharmacological advances in insulin therapy include the refinement of extremely rapid insulin analogs, alternate insulin-delivery routes, liver-selective insulins, add-on drugs that enhance insulin effect, and glucose-responsive insulin molecules. The greatest future impact will come from combining these pharmacological solutions with existing automated insulin delivery methods that integrate insulin pumps and glucose sensors. These systems will use algorithms enhanced by machine learning, supplemented by technologies that include activity monitors and sensors for other key metabolites such as ketones. The future challenges facing clinicians and researchers will be those of access and broad clinical implementation.

Interindividual Variability in the Pharmacodynamic and Pharmacokinetic Characteristics of Recombinant Human Insulin and Insulin Aspart

PURPOSE

The present study compared the interindividual variability in the pharmacodynamic (PD) and pharmacokinetic (PK) properties of a short-acting recombinant human insulin to those of insulin aspart through manual euglycemic glucose clamp tests.

METHODS

Sixty healthy Chinese male volunteers were randomly assigned to receive human insulin or insulin aspart, administered via SC injection (0.2 U/kg). For the evaluation of interindividual variability in PD and PK properties (glucose infusion rate [GIR], insulin concentration [INS]) through euglycemic clamp studies, %CVs were calculated, and PK/PD interindividual variability was compared between the 2 groups.

FINDINGS

The differences between the human insulin and insulin aspart groups in interindividual variabilities in total AUCs of the GIR (19% vs 21%) and INS (14% vs 17%) were not significant. The interindividual variabilities in AUCgir_0-120min, early T_max50%, and AUCins_0-120min were lower in the insulin aspart group than in the human insulin group (22% vs 44%, 21% vs 35%, and 22% vs 28%, respectively; all, P ˂ 0.05), while the interindividual variabilities in the AUCs of GIR_120-600min and INS_120-600min were higher with insulin aspart than with human insulin (29% vs 20%, 51% vs 30%; both, P ˂ 0.05).

IMPLICATIONS

The overall interindividual variability with insulin aspart was similar to that with recombinant human insulin. Yet insulin concentration and metabolic effect during the declining period were more variable with insulin aspart compared to human insulin in these healthy male subjects.

Nanomedicine-Based Strategies for Diabetes: Diagnostics, Monitoring, and Treatment

Traditional methods for diabetes management require constant and tedious glucose monitoring (GM) and insulin injections, impacting quality of life. The global diabetic population is expected to increase to 439 million, with approximately US$490 billion in healthcare expenditures by 2030, imposing a significant burden on healthcare systems worldwide. Recent advances in nanotechnology have emerged as promising alternative strategies for the management of diabetes. For example, implantable nanosensors are being developed for continuous GM, new nanoparticle (NP)-based imaging approaches that quantify subtle changes in β cell mass can facilitate early diagnosis, and nanotechnology-based insulin delivery methods are being explored as novel therapies. Here, we provide a holistic summary of this rapidly advancing field compiling all aspects pertaining to the management of diabetes.