Lydia Marie DeWitt and Mary Butler Kirkbride: Prototypical Circa-Early-1900s Women of Pathology and an Analysis of Their Contributions to the Discovery of Insulin

CONTEXT.—

The year 2023 marks the centenary of the Nobel Prize honoring the discovery of insulin. Little-known experimental pathologists Lydia DeWitt, MD, at the University of Michigan and Mary Kirkbride, DSc [Hon], at Columbia University, both just beginning their academic careers, made independent contributions to the discovery that have never been critically examined. This happened at a time when it was exceedingly rare for women to work in pathology.

OBJECTIVE.—

To explore the facilitative roles of DeWitt and Kirkbride in the discovery of insulin and to examine their trail-breaking careers in academic pathology.

DESIGN.—

Available primary and secondary historical resources were reviewed.

RESULTS.—

DeWitt made and tested pancreatic extracts from duct-ligated atrophic pancreas (ie, Frederick Banting's great idea to prevent digestion of its hypothetical internal secretion) 15 years before Banting; Banting was unaware of her work. His idea came from reading a paper by pathologist Moses Barron. Prior duct-ligation studies had sometimes been viewed with skepticism because histologic identification of islets in atrophic duct-ligated pancreata was imperfect; Kirkbride addressed this with histochemical staining, convincing Barron and, therefore, indirectly influencing and motivating Banting. The lives and convoluted careers of these 2 early-20th-century women are explored and compared with those of other contemporary women in pathology. A unifying pattern becomes clear: careers in experimental pathology and bacteriology were accepted but performing clinical work in anatomic pathology was not.

CONCLUSIONS.—

Both DeWitt and Kirkbride are prototypical early-20th-century women in academic pathology whose careers were constrained by gender. However, Kirkbride made a unique and unrecognized contribution to the discovery of insulin.

[Evolution of insulin therapy: past, present, future]

2021 marks the 100th anniversary of the discovery of insulin, an event that forever changed the lives of people with diabetes mellitus. At present patients around the world experience the miracle of insulin therapy every day. A disease that used to kill children and teenagers in 2 years in 1920 has become a disease that can be controlled with a possibility to lead a long productive life. Over the past century, the great discovery of Banting, Best and Collip has forever changed the world and saved millions of lives. This review is devoted to the history of the development of insulin and its further improvement: from the moment of discovery to the present days. Various generations of insulin are considered: from animals to modern ultrashort and basal analogues. The article ends with a brief review of current trends in the development of new delivery methods and the development of new insulin molecules. Over the past century, insulin therapy has come a long way, which has significantly improved the quality of life of our patients. But research is actively continuing, including in the field of alternative methods of insulin delivery, which are more convenient for the patient, as well as in the development of «smart» molecules that will have a glucose-dependent effect.

The continuum of insulin development viewed in the context of a collaborative process toward leveraging science to save lives: Following the trail of publications and patents one century after insulin's first use in humans

Nearly 100 years ago, diabetes, a disease expected to reach global prevalence of at least 10% within the decade, was a fatal diagnosis. This year of 2022 marks a century since insulin, a lifesaving treatment for those living with diabetes, was purified, tested in humans, and brought to the bedside through widespread commercial production, thus saving countless lives. Insulin's arrival to the world stage was acknowledged with the 1923 Nobel Prize in Physiology or Medicine for "the discovery of insulin", the first among several Prizes awarded to honor scientific work on insulin. This initial awarding has been the subject of significant controversy since, as numerous other scientists paved the way towards the ultimate success, and priority for the true "discovery of insulin" has been argued for many other scientists. The intention and regulations around the Nobel Prize nomination and award process presented herein offer insight into the 1923 Nobel prize designation for the Toronto group, which distinguished itself in the accomplishment by their success in purifying insulin from pancreatic extract and in bringing insulin to worldwide production and the homes of those who needed it. However, a continuous, collaborative process involving contributors spanning centuries and continents was required for the development, rather than discovery, of insulin therapy and its benefits to humanity. This should be the story's enduring legacy. The prior 100 years have witnessed a series of significant innovations in insulin development and therapeutics, but both a cure for diabetes and equitable insulin access remain out of reach and require inspired attention and continuous diligent efforts.

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Discovery of insulin. If the symptoms of diabetes have been known since Antiquity, it is at the end of the 19th century that several investigators searched for the active substance of the pancreas and endeavoured to produce extracts that lowered blood and urine glucose and decreased polyuria in pancreatectomized dogs. The breakthrough came 100 years ago when the team of Frederick Banting, Charles Best and James Collip, working in the Department of Physiology, headed by John MacLeod at the University of Toronto, managed to obtain pancreatic extracts that could be used to treat patients and rescue them from the edge of death by starvation, the only treatment then available. This achievement was quickly recognized by the Nobel Prize in Physiology or Medicine to Banting and MacLeod in 1923. The discovery has had important scientific, industrial and clinical developments still efficient nowadays.

[The insulin receptor discovery is 50 years old - A review of achieved progress]

The isolation of insulin from the pancreas and its purification to a degree permitting its safe administration to type 1 diabetic patients were accomplished 100 years ago at the University of Toronto by Banting, Best, Collip and McLeod and constitute undeniably one of the major medical therapeutic revolutions, recognized by the attribution of the 1923 Nobel Prize in Physiology or Medicine to Banting and McLeod. The clinical spin off was immediate as well as the internationalization of insulin's commercial production. The outcomes regarding basic research were much slower, in particular regarding the molecular mechanisms of insulin action on its target cells. It took almost a half-century before the determination of the tri-dimensional structure of insulin in 1969 and the characterization of its cell receptor in 1970-1971. The demonstration that the insulin receptor is in fact an enzyme named tyrosine kinase came in the years 1982-1985, and the crystal structure of the intracellular kinase domain 10 years later. The crystal structure of the first intracellular kinase substrate (IRS-1) in 1991 paved the way for the elucidation of the intracellular signalling pathways but it took 15 more years to obtain the complete crystal structure of the extracellular receptor domain (without insulin) in 2006. Since then, the determination of the structure of the whole insulin-receptor complex in both the inactive and activated states has made considerable progress, not least due to recent improvement in the resolution power of cryo-electron microscopy. I will here review the steps in the development of the concept of hormone receptor, and of our knowledge of the structure and molecular mechanism of activation of the insulin receptor.

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.

Insulin Centennial: Milestones influencing the development of insulin preparations since 1922

During 1921 to 1922, a team effort by Banting, Macleod, Collip and Best isolated and purified insulin and demonstrated its life-giving properties, giving rise to the birth of insulin therapy. In the early years (1922-1950), priorities revolved around the manufacture of insulin to meet demand, improving purity to avoid allergic reactions, establishing insulin standards and increasing its duration of action to avoid multiple daily injections. Shortly after the emergence of insulin, Joslin and Allen advocated the need to achieve and maintain good glycaemic control to realize its full potential. Although this view was opposed by some during a dark period in the history of insulin, it was subsequently endorsed some 60 years later endorsed by the Diabetes Control and Complications Trial and United Kingdom Prospective Diabetes Study. Major scientific advances by the Nobel Laureates Sanger, Hodgkin, Yalow and Gilbert and also by Steiner have revolutionized the understanding of diabetes and facilitated major advances in insulin therapy. The more recent advent of recombinant technology over the last 40 years has provided the potential for unlimited source of insulin, and the ability to generate various insulin 'analogues', in an attempt to better replicate normal insulin secretory patterns. The emerging biosimilars now provide the opportunity to improve availability at a lower cost.

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.

Insulin Therapy: The Discovery That Shaped a Century

The events and people surrounding the discovery of insulin as an effective therapy for diabetes in 1921 represent a compelling story that is directly relevant to the lives, and indeed the existence, of tens of millions of people worldwide. This story begins in the 19th century with the recognition that diabetes is a disease of hyperglycemia that arises because of the absence of a pancreatic hormone, that rapidly leads to death in people classified as having "thin diabetes" and that is linked to serious end-organ damage and other health consequences in people identified as having "fat diabetes." It continues with the recognition that pancreatic extracts can treat this problem in de-pancreatectomized dogs, and culminates with the dogged determination of a young, newly certified Canadian physician, Frederick Banting. Together with his supervisor, Professor John J.R. MacLeod (head of physiology at the University of Toronto), Banting, Charles H. Best (a physiology student) and James Collip (a professor of biochemistry at the University of Alberta, on sabbatical leave in Toronto) repeated these dog experiments and then successfully tested a purified pancreatic extract in a 13-year-old boy with type 1 diabetes in January 1922. This first successful test was followed by the rapid development and dissemination of the technology for insulin production worldwide. These events and insulin therapy's lifesaving effects on people with type 1 diabetes led to the awarding of the 1923 Nobel Prize in Physiology or Medicine to Banting and MacLeod, who shared their awards with Best and Collip.

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.

Insulin therapy development beyond 100 years

The first insulin preparation capable of consistently lowering blood glucose was developed in 1921. But 100 years later, blood glucose control with insulin in people with diabetes is nearly universally suboptimal, with essentially the same molecule still delivered by the same inappropriate subcutaneous injection route. Bypassing this route with oral administration appears to have become technologically feasible, accelerating over the past 50 years, either with packaged insulin peptides or by chemical insulin mimetics. Some of the problems of prospective unregulated absorption of insulin into the circulation from subcutaneous depots might be overcome with glucose-responsive insulins. Approaches to these problems could be modification of the peptide by adducts, or the use of nanoparticles or insulin patches, which deliver insulin according to glucose concentration. Some attention has been paid to targeting insulin preferentially to different organs, either by molecular engineering of insulin, or with adducts. But all these approaches still have problems in even beginning to match the responsiveness of physiological insulin delivery to metabolic requirements, both prandially and basally. As would be expected, for all these technically complex approaches, many examples of abandoned development can be found. Meanwhile, it is becoming possible to change the duration of action of subcutaneous injected insulin analogues to act even more rapidly for meals, and towards weekly insulin for basal administration. The state of the art of all these approaches, and the barriers to success, are reviewed here.

Insulin signaling in health and disease

The molecular mechanisms of cellular insulin action have been the focus of much investigation since the discovery of the hormone 100 years ago. Insulin action is impaired in metabolic syndrome, a condition known as insulin resistance. The actions of the hormone are initiated by binding to its receptor on the surface of target cells. The receptor is an α2β2 heterodimer that binds to insulin with high affinity, resulting in the activation of its tyrosine kinase activity. Once activated, the receptor can phosphorylate a number of intracellular substrates that initiate discrete signaling pathways. The tyrosine phosphorylation of some substrates activates phosphatidylinositol-3-kinase (PI3K), which produces polyphosphoinositides that interact with protein kinases, leading to activation of the kinase Akt. Phosphorylation of Shc leads to activation of the Ras/MAP kinase pathway. Phosphorylation of SH2B2 and of Cbl initiates activation of G proteins such as TC10. Activation of Akt and other protein kinases produces phosphorylation of a variety of substrates, including transcription factors, GTPase-activating proteins, and other kinases that control key metabolic events. Among the cellular processes controlled by insulin are vesicle trafficking, activities of metabolic enzymes, transcriptional factors, and degradation of insulin itself. Together these complex processes are coordinated to ensure glucose homeostasis.

The discovery of insulin revisited: lessons for the modern era

2021 to 2022 marks the one hundredth anniversary of ground-breaking research in Toronto that changed the course of what was, then, a universally fatal disease: type 1 diabetes. Some would argue that insulin's discovery by Banting, Best, Macleod, and Collip was the greatest scientific advance of the 20th century, being one of the first instances in which modern medical science was able to provide lifesaving therapy. As with all scientific discoveries, the work in Toronto built upon important advances of many researchers over the preceding decades. Furthermore, the Toronto work ushered in a century of discovery of the purification, isolation, structural characterization, and genetic sequencing of insulin, all of which influenced ongoing improvements in therapeutic insulin formulations. Here we discuss the body of knowledge prior to 1921 localizing insulin to the pancreas and establishing insulin's role in glucoregulation, and provide our views as to why researchers in Toronto ultimately achieved the purification of pancreatic extracts as a therapy. We discuss the pharmaceutical industry's role in the early days of insulin production and distribution and provide insights into why the discoverers chose not to profit financially from the discovery. This fascinating story of bench-to-beside discovery provides useful considerations for scientists now and in the future.

100 YEARS OF INSULIN: A brief history of diabetes genetics: insights for pancreatic beta-cell development and function

Since the discovery of insulin 100 years ago, our knowledge and understanding of diabetes have grown exponentially. Specifically, with regards to the genetics underlying diabetes risk, our discoveries have paralleled developments in our understanding of the human genome and our ability to study genomics at scale; these advancements in genetics have both accompanied and led to those in diabetes treatment. This review will explore the timeline and history of gene discovery and how this has coincided with progress in the fields of genomics. Examples of genetic causes of monogenic diabetes are presented and the continuing expansion of allelic series in these genes and the challenges these now cause for diagnostic interpretation along with opportunities for patient stratification are discussed.

Living with Insulin: The story of insulin from people with diabetes

The history of insulin is rightly considered one of the most beautiful stories in medicine which goes even further than the extraordinary result of tens of millions of lives saved. Without a doubt, it constitutes a major achievement for medical science which, especially in the last 50 years, has led to an impressive acceleration in the succession of new treatment opportunities. We are going to describe the history of insulin therapy, the history we lived from two different angles as people living with type 1 diabetes, and obviously also as diabetologists, but as diabetologists with diabetes. Without a doubt, insulin and his story constitutes a major achievement for medical science which has led to an impressive acceleration in the succession of new treatment opportunities. Care opportunities that have not only allowed fundamental improvements in outcomes, but have also and above all impacted the quality of life of people with diabetes. Summarizing one hundred years of insulin is no simple endeavor. In our view, it would be easier, and probably more befitting, to focus on the last 50 years, namely the period we have lived closely and personally together with insulin. More to the point, these last 50 years have witnessed a dramatic acceleration of research and innovation. In our opinion, it is precisely the innovations in insulin therapy introduced from the last decades that fully justify the description of events in this incredible period as "the miracle of insulin". We'll describe how the most important innovations introduced in the last decades had impact on what we have nowadays, as patients and diabetologits: today, we can finally adapt insulin therapy to the patient's life or lifestyle, reversing what was the perception of patients until 20 years, when insulin was considered, by the most, as an obstacle, which seemed insurmountable to some, to a free and unconstrained life.

Diabetes in pregnancy 100 years after the discovery of insulin: Hot topics and open questions to be addressed in the coming years

By making it possible for women with diabetes to achieve their family planning goals, the discovery of insulin ushered in the field of diabetes in pregnancy. The ensuing century has witnessed tremendous advances, with clinical focus on preconception planning and maternal glycemic control making successful pregnancy an achievable goal. Currently, the global epidemic of overweight/obesity has led to maternal hyperglycemia now affecting one in every six pregnancies worldwide, prompting intense research interest. Topics of particular interest include (i) the optimal approach to diagnosing gestational diabetes mellitus (GDM); (ii) the emergence of GDM as a chronic metabolic disorder identifying future risk of non-communicable disease; (iii) the transgenerational impact of maternal glycemia as per the Developmental Origins of Health and Disease; and (iv) the application of new technology for optimizing clinical management. These topics have raised exciting questions such as (i) whether the treatment of diabetes in pregnancy can impact growth/development in childhood, (ii) whether GDM can be prevented, and (iii) whether the diagnosis of GDM could facilitate the prevention of type 2 diabetes and cardiovascular disease. Indeed, this field may be on the precipice of a golden era of new concepts and evidence to optimize the health of mother and child.

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.

Realising the long-term promise of insulin therapy: the DCCT/EDIC study

The introduction of insulin in the treatment of juvenile-onset, now type 1, diabetes mellitus transformed a rapidly fatal disease into a chronic degenerative one. During the insulin-treatment era, long-term microvascular and cardiovascular complications proved to be the bane of existence for people with type 1 diabetes, leading to blindness, kidney failure, amputations, cardiovascular disease (CVD) and premature mortality. The nascent understanding of the link between non-physiologically regulated glucose levels and these complications led to the development of new treatment tools in the 1970s and 1980s that facilitated the delivery of insulin to achieve glucose levels closer to non-diabetic levels. These therapeutic advances set the stage for definitive testing of the glucose hypothesis. The Diabetes Control and Complications Trial (DCCT), supported by the National Institute of Diabetes Digestive and Kidney Diseases, National Institutes of Health (NIH), definitively established the benefits and risks of intensive therapy that substantially lowered mean blood glucose levels, measured by HbA_1c, over a mean 6.5 years of therapy. Intensive therapy in the DCCT, resulting in a mean HbA_1c of ~7% (53 mmol/mol), reduced the development and progression of early microvascular and neurological complications associated with diabetes by 34-76% compared with the conventional-treatment group, which maintained an HbA_1c of ~9% (75 mmol/mol). Intensive therapy was also associated with weight gain and a threefold increased risk for hypoglycaemia. At the end of the DCCT, a long-term observational follow-up study, the Epidemiology of Diabetes Interventions and Complications (EDIC) study, commenced. Despite the convergence of HbA_1c levels between the two groups during EDIC, owing to the adoption of intensive therapy by the original DCCT conventional-treatment group and the return of all participants to their own healthcare providers for diabetes care, the development and progression of complications continued to be substantially less in the original intensive-treatment group vs the conventional-treatment group; this phenomenon was termed 'metabolic memory'. The DCCT demonstrated a major reduction in early-stage complications with intensive therapy and the metabolic memory phenomenon during EDIC contributed to a substantially lower burden of advanced complications over time. These included a 57% lower risk of CVD events and 33% lower rate of mortality in the original intensive-treatment group compared with the conventional-treatment group. DCCT/EDIC has ushered in the intensive-treatment era, which has been universally adopted and includes the goal of achieving HbA_1c levels less than 7% (53 mmol/mol) for most patients. Although the challenge of making intensive therapy (with the aim of achieving normoglycaemia) as widely accessible and safe as possible remains, continuing improvements in insulin therapy 100 years after its introduction promise a brighter future for people with type 1 diabetes.

The discovery of insulin in Toronto: beginning a 100 year journey of research and clinical achievement

There has been a great deal of controversy regarding priority of discovery of insulin. Indeed, many scientists made important and, in some cases, seminal contributions to identifying the endocrine role of the pancreas and the potential for pancreatic extracts to have a glucose-lowering effect. The purpose of this article is to describe the early experiences with respect to research leading to the discovery of insulin in Toronto (ON, Canada). The experiments conducted at the University of Toronto resulted in the first demonstration that a pancreatic extract could be prepared that would consistently lower glucose, reverse ketosis and arrest the catabolic effects of type 1 diabetes. The remarkably rapid commercial production of insulin soon followed. The Toronto story begins on 17 May 1921, when Frederick Banting and Charles Best began their summer research project in the laboratory of John James Rickard Macleod, and we are now celebrating the 100th anniversary of this landmark achievement. The article herein outlines the steps leading up to the discovery of insulin and provides an overview of some of the key developments in insulin therapy over the past 100 years.

100th anniversary of the discovery of insulin perspective: insulin and adipose tissue fatty acid metabolism

Insulin inhibits systemic nonesterified fatty acid (NEFA) flux to a greater degree than glucose or any other metabolite. This remarkable effect is mainly due to insulin-mediated inhibition of intracellular triglyceride (TG) lipolysis in adipose tissues and is essential to prevent diabetic ketoacidosis, but also to limit the potential lipotoxic effects of NEFA in lean tissues that contribute to the development of diabetes complications. Insulin also regulates adipose tissue fatty acid esterification, glycerol and TG synthesis, lipogenesis, and possibly oxidation, contributing to the trapping of dietary fatty acids in the postprandial state. Excess NEFA flux at a given insulin level has been used to define in vivo adipose tissue insulin resistance. Adipose tissue insulin resistance defined in this fashion has been associated with several dysmetabolic features and complications of diabetes, but the mechanistic significance of this concept is not fully understood. This review focusses on the in vivo regulation of adipose tissue fatty acid metabolism by insulin and the mechanistic significance of the current definition of adipose tissue insulin resistance. One hundred years after the discovery of insulin and despite decades of investigations, much is still to be understood about the multifaceted in vivo actions of this hormone on adipose tissue fatty acid metabolism.

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 Art of Insulin Treatment:' Diabetes, Insulin, and the 1920s

Soon after the discovery of insulin in the early 1920s, the popular press celebrated the miraculous discovery. Although insulin had no curative effect on the chronic state of diabetes, it was frequently heralded as a "cure." This paper examines how the discovery of insulin intersected with the rise of diabetic technology and the transfer of medical technology to the home setting. By analyzing diabetic manuals written for patients and physicians, letters exchanged between patient and physician, medical journals, magazines and newspapers, I trace how patients learned about insulin and more significantly how patients adopted measurement technologies designed to allow better home administration of insulin. This included acquiring knowledge about nutritional content and scales, maintaining sterile glass syringes, sharpening needles, using chemistry to measure sugar in the urine, and recording various measurements into meaningful text for patient-physician dialogue. As diabetes was re-imagined as a chronic and controllable illness, patients and physicians alike grappled with the promises and limitations of new medical technologies. This historical perspective offers a lens for better understanding the process of implementing diabetic treatment plans that required home testing, measurement, and recording of medical data. Such processes centered the importance of patient-centered work and the value of diabetic technologies. Much of this discourse is outlined in diabetic manuals of the 1920s.

C-Peptide replacement therapy in type 1 diabetes: are we in the trough of disillusionment?

Type 1 diabetes is associated with such complications as blindness, kidney failure, and nerve damage. Replacing C-peptide, a hormone normally co-secreted with insulin, has been shown to reduce diabetes-related complications. Interestingly, after nearly 30 years of positive research results, C-peptide is still not being co-administered with insulin to diabetic patients. The following review discusses the potential of C-peptide as an auxilliary replacement therapy and why it's not currently being used as a therapeutic.

Glucose-Insulin-Potassium Techniques in Cardiac Surgery: Historical Overview and Future Perspectives

Since the days of the first cardiac surgical operations in the previous century, myocardial preservation has been an essential component of the successful outcome of these procedures. Although many different techniques to achieve myocardial preservation and modulation have been described in the past 50 years, this review focuses on the use of glucose, insulin, and potassium (GIK) and its effect on ischemic and postischemic myocardium.

[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).

[A brief history of the development of realization on insulin]

The islet cells were found in 1869 and officially named "ilots de Langerhans" in 1893. The secretions of pancreas were found to contain ingredients to control blood sugar in 1890 which was named insulin in 1909. However, it was not until 1921 that insulin was purified, which was used to treat diabetes in 1922. American scholars obtained insulin crystals firstly in 1926. Since then, increasing knowledge were found in insulin, thus arousing a rapid development of its synthesis. Furthermore, Chinese scholars synthesized crystalline of bovine insulin firstly in 1965. Due to the presence of immunogenicity in animal insulin, Novo Nordisk used recombinant DNA technology to synthesize human insulin and for clinical use in 1980s. And Tonghua Dongbao Company developed the first recombinant human insulin of China in 1998. Meanwhile, insulin injections have also been changed from the ordinary syringes to dedicated insulin syringes, from the insulin pens to the insulin pumps, and eventually to the most advanced needleless syringes. Currently, academia is endeavored in the development of non-injectable insulin formulations.