Insulin discovery: A pivotal point in medical history

The discovery of insulin in 1921 - due to the efforts of the Canadian research team based in Toronto - has been a landmark achievement in the history of medicine. Lives of people with diabetes were changed forever, considering that in the pre-insulin era this was a deadly condition. Insulin, right after its discovery, became the first hormone to be purified for human use, the first to be unraveled in its amino acid sequence and to be synthetized by DNA-recombinant technique, the first to be modified in its amino acid sequence to modify its duration of action. As such the discovery of insulin represents a pivotal point in medical history. Since the early days of its production, insulin has been improved in its pharmacokinetic and pharmacodynamic properties in the attempt to faithfully reproduce diurnal physiologic plasma insulin fluctuations. The evolution of insulin molecule has been paralleled by evolution in the way the hormone is administered. Once-weekly insulins will be available soon, and glucose-responsive "smart" insulins start showing their potential in early clinical studies. The first century of insulin as therapy was marked by relentless search for better formulations, a search that has not stopped yet. New technologies may have, indeed, the potential to provide further improvement of safety and efficacy of insulin therapy and, therefore, contribute to improvement of the quality of life of people with diabetes.

One-hundred year evolution of prandial insulin preparations: From animal pancreas extracts to rapid-acting analogs

The first insulin preparation injected in humans in 1922 was short-acting, extracted from animal pancreas, contaminated by impurities. Ever since the insulin extracted from animal pancreas has been continuously purified, until an unlimited synthesis of regular human insulin (RHI) became possible in the '80s using the recombinant-DNA (rDNA) technique. The rDNA technique then led to the designer insulins (analogs) in the early '90s. Rapid-acting insulin analogs were developed to accelerate the slow subcutaneous (sc) absorption of RHI, thus lowering the 2-h post-prandial plasma glucose (PP-PG) and risk for late hypoglycemia as comparing with RHI. The first rapid-acting analog was lispro (in 1996), soon followed by aspart and glulisine. Rapid-acting analogs are more convenient than RHI: they improve early PP-PG, and 24-h PG and A1C as long as basal insulin is also optimized; they lower the risk of late PP hypoglycemia and they allow a shorter time-interval between injection and meal. Today rapid-acting analogs are the gold standard prandial insulins. Recently, even faster analogs have become available (faster aspart, ultra-rapid lispro) or are being studied (Biochaperone lispro), making additional gains in lowering PP-PG. Rapid-acting analogs are recommended in all those with type 1 and type 2 diabetes who need prandial insulin replacement.

Winner's curse: The sad aftermath of the discovery of insulin

Every young researcher dreams of making a great discovery, but few achieve it. If they do, success does not guarantee happiness. There is little satisfaction in discovering something if others get the credit, and those who achieve fame must face the 'winner's curse' of living up to their reputation. Few discoveries have been more dramatic than the isolation of insulin which, as Michael Bliss said, resembled a secular miracle. And yet, as he also pointed out, this great discovery brought little happiness to those who made it. Some were sidelined, and Banting and Best were saddled with the winner's curse. Here, we look at the ways in which a great discovery can haunt its discoverers.

100 years of physiology, discrimination and wonder

There has been 100 years of research detailing the role of insulin in glucose, protein and free fatty acid metabolism. We explore the learnings though evolution and changes in management with an understanding of how it has impacted the care of people with diabetes. The discrimination endured is described and recent advances to empower and counter this are highlighted.

A century past the discovery of insulin: global progress and challenges for type 1 diabetes among children and adolescents in low-income and middle-income countries

Type 1 diabetes is on the rise globally; however, the burden of mortality remains disproportionate in low-income and middle-income countries (LMICs). As 2021 marks 100 years since the discovery of insulin, we revisit progress, global burden of type 1 diabetes trends, and understanding of the pathogenesis and management practices related to the disease. Despite much progress, inequities in access and availability of insulin formulations persist and are reflected in differences in survival and morbidity patterns related to the disease. Some of these inequities have also been exacerbated by health-system challenges during the COVID-19 pandemic. There is a clear opportunity to improve access to insulin and related essential technologies for improved management of type 1 diabetes in LMICs, especially as a part of universal health coverage. These improvements will require concerted action and investments in human resources, community engagement, and education for the timely diagnosis and management of type 1 diabetes, as well as adequate health-care financing. Further research in LMICs, especially those in Africa, is needed to improve our understanding of the burden, risk factors, and implementation strategies for managing type 1 diabetes.

100 YEARS OF INSULIN: Arresting or curing type 1 diabetes: an elusive goal, but closing the gap

Type 1 diabetes is one of the most common chronic diseases in children and adolescents, but remains unpreventable and incurable. The discovery of insulin, already 100 years ago, embodied a lifesaver for people with type 1 diabetes as it allowed the replacement of all functions of the beta cell. Nevertheless, despite all technological advances, the majority of type 1 diabetic patients fail to reach the recommended target HbA1c levels. The disease-associated complications remain the true burden of affected individuals and necessitate the search for disease prevention and reversal. The recognition that type 1 diabetes is a heterogeneous disease with an etiology in which both the innate and adaptive immune system as well as the insulin-producing beta cells intimately interact, has fostered the idea that treatment to specific molecular or cellular characteristics of the patient groups will be needed. Moreover, robust and reliable biomarkers to detect type 1 diabetes in the early (pre-symptomatic) phases are wanted to preserve functional beta cell mass. The pitfalls of past therapeutics along with the perspectives of current therapies can open up the path for future research.

Insulin's centenary: the birth of an idea

At 2:00 h on Oct 31, 1920, Frederick G Banting, a surgeon practising in London, ON, Canada, conceived an idea to isolate the internal secretion of the pancreas. The following week, he met with noted scientist John J R Macleod in Toronto, ON, Canada, and they developed a research plan. By August, 1921, Banting and his student assistant Charles H Best had prepared an effective extract from a canine pancreas. In January, 1922, biochemist James B Collip isolated insulin that was sufficiently pure for human use. On Oct 25, 1923, Banting and Macleod received the Nobel Prize in Physiology or Medicine for the discovery of insulin. Here, we recount the most relevant events before and after the fateful early morning of Oct 31, 1920, which culminated in the discovery and clinical use of insulin.

Biometrics and citizenship: Measuring diabetes in the United States in the interwar years

In 1936, the journalist Hannah Lees published "Two Million Tightrope Walkers," drawing attention to the significant number of people in the United States estimated to have diabetes. Focusing on how people with diabetes should live, she emphasized the importance of recording the exact values of everything they ate and avoiding all "riotous living" lest they be unable to keep careful measurements of calories, insulin, and sleep. Employing two meanings of measured - as counted and as moderate - Lees was doing more than communicating how someone might control their disease; she was also calling for a "controlled and self-reliant citizenry." Indeed, Lees insisted that diabetics who followed a regime of measurement "make a good deal better citizens than the average." Drawing on the writings of Lees and other social commentators, I explore the link between biometrics, citizenship, and diabetes in the United States in the interwar years. In particular, I look at how this disease came to symbolize both the regimes of discipline thought to be necessary in a society moving to consumption as its economic motor, and the fears of what could happen if consumption ran amok. Biometrics, I argue, offered clinicians and patients a potent tool for measuring deviance and, potentially, for restoring a person to the "norm."

The past decade in type 2 diabetes and future challenges

There is today an exponential increase in prevalence of type 2 diabetes mellitus (T2DM), especially in young people. This downward shift in age of onset of T2DM has been shown by abundant evidence to be due to an increase in obesity among the young, the latter mainly attributable to unhealthy dietary habits and a sedentary lifestyle. It is therefore obvious that the prevention of diabetes rather its treatment is of is paramount importance. In the past decade, because concerns about the safety of antidiabetic agents took precedence over the issue of efficacy, almost all studies have been diabetes CVOTs and not traditional CVOTs. Until 2015, the evidence showed that antidiabetic agents are effective in terms of reduction of microvascular, as opposed to macrovascular, complications. However, following publication of the results of some new studies, it became clear that the new class of antidiabetic drugs, e.g., SGLT 2 inhibitors and GLP-1 agonists, are also effective in reducing cardiovascular disease (CVD). In the coming decade, numerous health challenges are expected to arise, the most important being the greater expansion of the therapeutic armamentarium for T2DM and the adoption of strategies for prevention of CVDs. In parallel, the new generation of antidiabetic agents will target the recently investigated pathophysiologic disorders of diabetes, while, ideally, treatments should include smart drugs without side effects.

ANNIVERSARY REVIEW: 50 years since the discovery of bromocriptine

Ergotism is the long-term ergot poisoning by ingestion of rye or other grains infected with the fungus Claviceps purpurea and more recently by excessive intake of ergot drugs. It has either neuropsychiatric or vascular manifestations. In the Middle Ages, the gangrenous poisoning was known as St. Anthony's fire, after the order of the Monks of St. Anthony who were particularly skilled at treating the condition. In 1917, Prof. Arthur Stoll returned home to Switzerland from Germany, to lead the development of a new pharmaceutical department at Sandoz Chemical Company. Stoll, using the special methods of extraction learned from his work with his mentor Willstetter, started his industrial research work with ergot. He succeeded in isolating, from the ergot of rye, ergotamine as an active principle of an old popular remedy for excessive post-partum bleeding. The success of this discovery occurred in 1918 and was translated into a pharmaceutical product in 1921 under the trade name Gynergen. In subsequent work, Stoll and his team were leaders in identifying the structure of the many other alkaloids and amines produced by Claviceps purpurea This was the cultural background and scientific foundation on which bromocriptine was discovered.

[Transition and perspectives of antidiabetic agents]

History of oral hypoglycemic agents (OHA) started in 1942 that was 20 years delayed to the discovery of insulin. The first two OHAs (sulfonylurea and biguanide) were discovered by chance. Ancient knowledge regarding antidiabetic agents present in nature is significant for the development of some drugs. For instance, principal components of biguanide, α-glucosidase inhibitors are contained in French lilac and mulberry leaves respectively, that are ancient diabetic medications. Thiazolidinediones, incretin related drugs, were discovered by a result of great effort paid to structural ingenuity and search of the compound. SGLT2 inhibitors are a new class of antidiabetic agents which has various potentials beyond lowering plasma glucose. In this review, we will discuss about transition and perspectives of antidiabetic agents.

[History of diabetes treatment in Czechoslovakia prior to 1989]

The article aims to outline the historical development of treatment of diabetes in Czechoslovakia. Information has been obtained mainly from two Czech journals, Časopis lékařů českých (The Journal of Czech Physicians, published since 1862) and Praktický lékař (The General Practitioner, published since 1921). Until the discovery of insulin, the treatment of diabetes was based on the use of different diets and a great benefit was obtained by spa treatment. In 1923, imported insulin appeared on the market in Czechoslovakia; insulin injections or substances from which insulin was prepared. In the years 1923-1945, insulin was produced by five companies, then insulin and oral antidiabetics were manufactured just by one firm Léčiva (Pharmaceuticals).

Transdermal innovations in diabetes management

Diabetes mellitus, an endocrine disorder affecting glucose metabolism, has been crippling mankind for the past two centuries. Despite the advancements in the understanding pertaining to its pathogenesis and treatment, the currently available therapeutic options are far from satisfactory. The growing diabetic population increases the gravity of the situation. The shortcomings of the conventional drug delivery systems necessitate the need to delve into other routes. On account of its merits over other routes, the transdermal approach has drawn the interest of the researchers around the world. The transdermal drug delivery systems are aimed to achieve therapeutic concentrations of the drug through skin. These systems are designed so that the drug can be delivered at a pre-determined and controlled rate. This makes it particularly conducive to treat chronic disorders like diabetes. Correspondingly, the adverse effects and inconvenience concomitant with oral and parentral route are circumvented. This article attempts to outline the development of transdermal drug delivery systems to optimize diabetes pharmacotherapy. It not only covers the transdermal approaches adopted to fine-tune insulin delivery, but also, discusses various transdermal drug delivery systems fabricated to improve the therapeutic performance of oral hypoglycaemic agents. Such formulations include the advanced drug delivery systems, namely, transferosomal gels, microemulsions, self-dissolving micropiles, nanoparticles, insulin pumps, biphasic lipid systems, calcium carbonate nanoparticles, lecithin nanoparticles; physical techniques such as iontophoresis and microneedles and, drugs formulated as transdermal patches. In addition to this, the authors have also shed light on the future prospects and patented and commercial formulations of antidiabetic agents.

Sulfonylureas and meglitinides: historical and contemporary issues

Insulin secretagogue therapy is commonly used in clinical practice. These agents may be utilized as first, second-line or adjunct therapy behind metformin for treatment of type 2 diabetes mellitus. Sulfonylureas and meglitinides are effective treatments, but cumulative data over decades of research raise concerns regarding universal prescribing. The role of insulin secretagogue therapy in β-cell failure, blunting of ischemic pre-conditioning, the incidence of hypoglycemia - specifically in at-risk populations, modest weight gain and the unproven link to cancer are discussed. Ultimately, many of the concerns appear to be agent and not class-specific with glibenclamide fairing the worst amongst all of the agents discussed.

Managing type 1 diabetes ‑ a journey from starvation to insulin pump

With the discovery of insulin in 1921, hopes were high that type 1 diabetes mellitus would soon be cured. However, this goal has remained elusive. Nevertheless, technological advances have improved the management of diabetes and the quality of life of patients with diabetes. One of these advances has been the development of the insulin pump. This article reviews the development of insulin pumps and outlines the advantages and disadvantages of insulin pumps currently available.

Treating type 1 diabetes: from strategies for insulin delivery to dual hormonal control

Type 1 diabetes is a disorder where slow destruction of pancreatic β-cells occurs through autoimmune mechanisms. The result is a progressive and ultimately complete lack of endogenous insulin. Due to β-cell lack, secondary abnormalities in glucagon and likely in incretins occur. These multiple hormonal abnormalities cause metabolic instability and extreme glycemic variability, which is the primary phenotype. As the disease progresses patients often develop hypoglycemia unawareness and defects in their counterregulatory defenses. Intensive insulin therapy may thus lead to 3-fold excess of severe hypoglycemia and severely hinder the effective and safe control of hyperglycemia. The main goal of the therapy for type 1 diabetes has long been physiological mimicry of normal insulin secretion based on monitoring which requires considerable effort and understanding of the underlying physiology. Attainment of this goal is challenged by the nature of the disease and our current lack of means to fully repair the abnormal endocrine pancreas interactive functions. As a result, various insulin preparations have been developed to partially compensate for the inability to deliver timely exogenous insulin directly to the portal/intrapancreatic circulation. It remains an ongoing task to identify the ideal routes and regimens of their delivery and potentially that of other hormones to restore the deficient and disordered hormonal environment of the pancreas to achieve a near normal metabolic state. Several recent technological advances help addressing these goals, including the rapid progress in insulin pumps, continuous glucose sensors, and ultimately the artificial pancreas closed-loop technology and the recent start of dual-hormone therapies.

Insulin therapy in type 2 diabetes mellitus: history drives patient care toward a better future

"Insulin will never be a success in the treatment of diabetics without the aid of the general practitioner."(1) These words, written by Elliott P. Joslin, MD, in 1923, still ring true today. After the first successful insulin injection was administered on January 23, 1922, to Leonard Thompson, a 14-year-old patient with type 1 diabetes mellitus at Toronto General Hospital, it did not take long before a diabetes clinic using insulin treatment was set up.(2) Insulin was subsequently provided to physicians in the United States for clinical trials, although many US patients with diabetes mellitus presented themselves to Sir Frederick Banting, MD, co-discover of insulin, in Toronto for insulin treatment. Within 2 years, insulin was being manufactured by multiple pharmaceutical companies and was available commercially in both the United States and Canada.(2) Almost immediately, health care professionals and others identified the problem of who was going to care for all of these patients. Patients were arriving at diabetes clinics expecting to receive insulin, often overwhelming the few physicians who were educated on the care of diabetic patients. For this reason, the physicians and nurses at the New England Deaconess Hospital in Boston initiated a teaching program so that general practitioners could learn all aspects of the management of diabetes.

Insulin preparations with prolonged effect

The discovery of insulin and its clinical application early in the last century dramatically improved the prospects of people with diabetes. However, the limitations of those initial, unmodified insulin preparations were quickly recognized; most notably, their relatively "short action" meant that multiple daily subcutaneous injections were required. This stimulated a concerted effort to modify the properties of insulin in order to extend the duration of its blood glucose-lowering effect, minimize dosing frequency, and decrease the burden of treatment. The first successful attempts to prolong insulin's action were achieved by modifying its formulation with additives such as protamine and zinc, culminating in the production of "intermediate-acting" neutral protamine Hagedorn (NPH) insulin in the 1940s and the lente family of insulins in the 1950s. However, NPH and lente insulins were still associated with several limitations, including considerable variability of effect and a pronounced peak in their time-action profile. In the 1980s, the focus of research moved toward the modification of insulin itself with the aim of producing a "long-acting" insulin that would better satisfy basal insulin requirements over the entire day. Once-daily insulin glargine was the first "long-acting" insulin analog in clinical practice, followed by once- or twice-daily insulin detemir and, more recently, insulin degludec, which is now being evaluated for administration at less frequent intervals. These analogs demonstrate several benefits over "intermediate-acting" insulins, including a lower risk of both overall hypoglycemia and nocturnal hypoglycemia and reduced day-to-day glucose variability, making it more feasible to achieve better fasting and overall glycemic control. Long-acting insulin analogs (insulin glargine and insulin detemir) are now firmly established as key tools in the battle against diabetes, and ongoing clinical research of insulin-based therapy should focus on treatment strategies to maximize their benefits. To date, the clinical experience with insulin degludec is limited but demonstrates it has comparable efficacy to insulin glargine.

History of diabetes: from ants to analogs

The earliest description of diabetes was documented in the writings of Hindu scholars as long as in 1500 BC. In 1921 the Canadian scientists Fredrick G. Banting, Charles H. Best, J. J. R. Macleod and James B. Collip discovered insulin, a peptide (small protein hormone) which lowers blood sugar. They extracted insulin from the islets of animal pancreases. A year later, in January 1922, bovine insulin was first given to humans by injection. The co-discoverers, in particular James Collip, continued their work to purify the insulin extract to make it safer and more effective. In 1936, protamine, a low-weight protein, was used to develop a suspension. In 1951 the amorphous 'lente' insulins- semilente, lente and ultralente were developed. After several years of laboratory work during the years 1963-1966 human insulin was chemically synthesized. In 1975, fully synthetic insulin was synthesized. Since 1996, different insulin analogues have been introduced worldwide. Insulin therapy is undergoing a paradigm shift now a days and at this hour we need to focus on the cardinal principles of initiating, optimizing, and intensifying the treatment for achieving adequate control.

[The return to life with insulin]

The Canadian Frederick Banting (1891-1941), in discovering the existence of insulin, was able to treat, for the first time, with efficiency, diabetic patients. This discovery and its application did not happen easily, in particular within his own team. In 1922, the Nobel Prize would reward this researcher, who died two decades later in an airplane crash.

Novel use of insulin in continuous-instillation negative pressure wound therapy as "wound chemotherapy"

Negative pressure wound therapy (NPWT) is frequently employed in the treatment of complex wounds. A variety of wound chemotherapeutic agents such as insulin, which acts as a growth factor, may prove helpful in treatment as well. We present a case report in which insulin was used as a chemotherapeutic agent in continuous-instillation NPWT. To our knowledge, this is the first report in the literature describing this method of delivery.

Vaccinium myrtillus as an antidiabetic medicinal plant--research through the ages

Bilberry leaves (Vaccinium myrtillus L.) were one of the most frequently used antidiabetic remedies of plant origin before the discovery of insulin. During the last century, many animal, clinical and phytochemical studies have been undertaken with this plant and its extracts and are summarized here. Overall, it must be concluded that the results were more or less disappointing and could not support the traditional use of bilberry leaves against diabetes mellitus which is sometimes recommended even up to the present day.

Insulin detemir: A historical perspective on a modern basal insulin analogue

Insulin detemir provides prolonged, reproducible blood glucose reduction through a mechanism unique among basal insulins. It was originally studied clinically in predominantly basal + bolus regimens and found to be associated with a low risk of hypoglycaemia compared to insulin NPH, and reduced weight gain compared to other basal insulins. Insulin detemir has been increasingly studied in basal-only insulin regimens in type 2 diabetes, in which an understanding of how to optimize its use has been built incrementally. Glycaemic control and limitation of weight gain tend to be maximized by once-daily (evening) dosing, earlier initiation and careful titration to appropriate fasting glucose targets.

The role of genealogy and clinical family histories in documenting possible inheritance patterns for diabetes mellitus in the pre-insulin era: part 2. Genealogic evidence for type 2 diabetes mellitus in Josephine Imperato's paternal and maternal lineages

Part 2 presents detailed genealogic information on Josephine Imperato's paternal and maternal lineages extending from four to seven generations into the nineteenth and eighteenth centuries. Among these lineages are some where early adult death over successive generations is perhaps indicative of type 2 diabetes mellitus (type 2 DM). These lineages, all in the town of San Prisco in Italy, include both paternal and maternal ones with the following surnames: Casaccia, Casertano, Cipriano, de Angelis, de Paulis, Peccerillo, Foniciello, di Monaco, Vaccarella, Valenziano, Ventriglia, and Zibella. Genealogic studies of eighteenth and nineteenth century vital records in this area of Italy cannot definitively establish type 2 diabetes mellitus as either an immediate or contributory cause of death. This is because causes of death were not recorded and because disease diagnostic capabilities were largely absent. Genealogic studies of those who lived in Italy in the eighteenth and nineteenth centuries can at best provide data on approximate age at time of death. Early adult death in this era was not uncommon. However, its presence over several successive generations in a lineage raises the possibility of inherited diseases prominent among which is type 2 DM.

[Historical review of Antidiabetic Drugs' discovery]

Early in the ancient Egyptian period 3, 500 years ago, people began to record the symptoms of diuresis related to Diabetes Mellitus. Thereafter, the cognition of Diabetes Mellitus in people evolved several times, that is: from simple symptom-recording to realizing that the essential pathogenesis is the kidney, and then recognizing that the root cause is the pancreas; from the cognition of islet cells to the separation and purification of insulin; from recognizing that sulfonamides have a hyperglycemic action to the appearance of dimethyldiguanide and the improvement of the method of Insulin's injection method. Reviewing this historical process can benefit a better realization and prevention and cure of Diabetes Mellitus.