Facts about Type I Diabetes Mellitus Diabetes was

Facts about Type I Diabetes Mellitus

“ Diabetes was long thought to be a kidney disease (Greek & Arabic Methodology).

“ Thomas Willis (1621 1679), discovered the sweetness of urine, hence, the name Diabetes Mellitus arised”

“Mathew Dobson (1776), identified glycosuria.

“Claude Bernard and Von Mering (1889), discovered in the same year that pancreatectomy causes diabetes”

“Fredrick Banting (1921), successfully, extracted insulin, gaining the Nobel prize for this great discovery”.

“Leonard Thompson (14 year old boy) & Elizabeth Hughes (aged 14 years), were the first patients to be treated with insulin in 1922.

Dear Mom, . . I look entirely different gaining every hour strength & weight. . it is truly miraculous. . I wish you could see the expression on there faces, they are so astounded in my unheard of progress. . Leonard, April, 1922

Insulin Secretion Site : B cells (Pancreatic Islets • of Langerhan’s). Mechanism : from secretory • granules of Proinsulin (in the Golgi complex of B cells). Factors Related : glucose, gut • hormones, A. As. , F. As. , ketone bodies, nerve supply& glucagon.

Insulin Secretion

INSULIN SECRETION Glu t 2 e cos lu G od Blo GLUCOSE GK G-6 -P PK PYRUVATES K+ _ + _+ INSULIN ATP _+ DEPOLARIZATION Ca 2+

Biphasic Glucose Stimulation 1 st phase: Rapid onset (with peak level after 1 -2 minutes) & Short duration. 2 nd phase: Delayed onset & Longer duration.

Insulin Secretion Curve Biphasic insulin response to a constant glucose stimulation (IVGTT - hyperglycemic Clamp) Insulin rate Basal Time (min) 4 60

Response to I. V. Glucose

Insulin Mechanism of action Carbohydrate metabolism Lipid metabolism Protein metabolism

Insulin Receptors Receptor-mediated endocytosis. • Gene transcription. • Glucose transporters. •

Insulin Receptors

Insulin Hypoglycemic Action Glucose storage. . Anabolic effect & Anticatabolic effect.

Insulin Lack

Insulin Deficiency

Insulin Defect Complications

Sorbitol Pathway

Diabetes Mellitus “ A metabolic disorder, with high risk of complications & chronic hyperglycemia (with or without glycosuria) “.

Prevalence of Insulin Disorders “ The prevalence worldwide varies from 2 -5% in developing countries, to 5 -10% in developed countries”. N. B. ( A cross-sectional study revealed incidence of 7 million cases in the Egyptian population at the year of 1992).

Diabetes: Clinical Features Symptoms: • Polyuria – Polydypsia=thirst – Polyphagia=appetite – Asthenia & Loss of weight – Signs: • No specific signs may be signs of complications

Diagnosis of D. Mellitus American Diabetes Association

Investigation of Diabetes Fasting Blood Glucose level • Post prandial blood glucose level • Glycosuria • Glycosylated haemoglobin. •

Glycosylated Haemoglobin Hb + G = Hb. A 1 (non reversible) • In hyperglycemia up to 20% or more. • Occurs in the active life span of the RBCs. • Gives information about the state of BGL • during the previous 2 months. •

Predisposing Factors IDDM Heredity. Histocomptability. Virus infection. Sesonality. Cell-mediated immunity. • • •

Seasonality

Stages of IDDM development

Age and insulin content