Obesity and its pathophysiology

explained about the reasons for obesity, its pathology, how to prevent obesity and how to overcome it. also discussed about the genes, receptors, enzymes and hormones involved in obesity.

1. PRESENTED BY AISWARYA THOMAS 2 nd YEAR PHARM D 1/28/2015 OBESITY 1 WELCOME

2. 1/28/2015 OBESITY 2

3. 1/28/2015 OBESITY 3

4. Dietary imbalance and over nutritio n may lead to diseases like obesity. Defined as an excess of adipose tissues that imparts health risk; a body weight of 20% excess over ideal weight for age, sex and height is considered a health risk. 1/28/2015 OBESITY 4

5. The most widely used method to gauge obesity is Body Mass Index(BMI) which is equal to weight in Kg/height in m 2 . A cut off BMI value of 30 is used for obesity in both men and women. 1/28/2015 OBESITY 5

6. 1/28/2015 OBESITY 6

7. Etiology Obesity results when caloric intake exceeds utilization. The imbalance of these two components can occur in the following situations : 1.Inadequate pushing of oneself away from dining table causing over eating. 2.Insufficient pushing of oneself out of the chair leading to inactivity and sedentary life style . 1/28/2015 OBESITY 7

8. 3.Genetic predeposition to develop obesity (heredity) . 4.Diets largely derived from carbohydrates and fats than protein-rich diet (fat and sugar rich diet). 5. Secondary obesity may result from diseases such as hypothyroidism, Cushing’s disease, insulinoma and hypothalamic disorders. 1/28/2015 OBESITY 8

9. Pathogenesis Adipocytes (lipid storing cells) comprise the adipose tissue, and are present in the vascular and stromal compartments of the body. Besides the function of fat storage, adipocytes also release endocrine regulating molecules . 1/28/2015 OBESITY 9

10. Molecules include : Energy regulating hormone( leptin ), Cytokines(TNF-alpha & IL-6), Insulin sensitivity regulating agents( adiponectin , resistin and RBP4), Prothrombotic factors( plasminogen activator inhibitor), BP regulating agent( angeotensingen ). 1/28/2015 OBESITY 10

11. 1/28/2015 OBESITY 11 Adipose mass is increased due to : enlargement of adipose cells due to excess of intra cellular lipid deposition increase in the number of adipocytes . Environmental factor of excess consumption of nutrients can lead to obesity.

12. 1/28/2015 OBESITY 12 Underlying molecular mechanisms of obesity are beginning to unfold that obesity is familial and is seen in identical twins. Recently, two obesity genes have been found : ob gene and its protein product lepton, ab gene and its protein product leptin.

13. 1/28/2015 OBESITY 13

14. 1/28/2015 OBESITY 14

15. 1/28/2015 OBESITY 15 The physiological role of leptin is to communicate to the central nervous system (CNS) the abundance of available energy store To suppress food intake To permit energy expenditure. The absence of leptin therefore leads to increased appetite and food intake that results in morbid obesity.

16. An absolute deficit of leptin does not underlie in most cases of obesity. Most obese individuals exhibit elevated circulating leptin levels, which implies the existence of leptin resistance. The failure of high levels of leptin to suppress feeding or decrease adiposity to prevent obesity is due to relative resistance to the catabolic effects of leptin action in obesity. 1/28/2015 OBESITY 16

17. 1/28/2015 OBESITY 17 COMPLICATIONS OF OBESITY 1.Diabetes Mellitus There is a strong association between obesity and type 2 diabetes mellitus, in both genders and all ethnic groups. 2. Hypertension It has been estimated that excess body weight may account for up to 26% of cases of hypertension in men and 28% in women. Not only is obesity linked with hypertension, but weight loss in obese subjects is associated with a decline in blood pressure

18. 1/28/2015 OBESITY 18 3.Dyslipidaemia Obesity is associated with an unfavorable lipid profile. Lipid abnormalities related to obesity include an elevated serum concentration of LDL & VLDL cholesterol, triglycerides and apolipoprotein B, as well as a reduction in serum HDL cholesterol. 4.Heart disease coronary artery disease heart failure atrial fibrillation.

19. 1/28/2015 OBESITY 19 5.Cerebrovascular disease 6.Respiratory disease Obstructive sleep apnoea Asthma 7.Gastrointestinal system Gastro esophageal reflux Gastro esophageal reflux disease (GORD) is a common disorder that has been linked to obesity. Most population-based studies showed a gradual increase in GORD symptoms as BMI increased . Hepatobiliary disease Non-alcoholic fatty liver disease (NAFLD)

20. 1/28/2015 OBESITY 20 8.Osteoarthritis It is most common in the knees and the ankles, which may be a consequence of trauma related to the excess body weight. 9.Cancer The WHO estimated that overweight and inactivity account for from a quarter to a third of all cancers of the breast, colon, endometrium, kidney and oesophagus .

21. 1/28/2015 OBESITY 21 10.Gynaecological and obstetric complications Obesity during pregnancy is associated with an increased risk of complications, including gestational diabetes, pre- eclampsia , and delivery complications such as macrosomia , shoulder dystocia and higher rates of caesarean sections and infections. Maternal obesity may also be an independent risk factor for neural tube defects and fetal mortality .

22. 1/28/2015 OBESITY 22 11.Surgical and anaesthetic complications 12. Chronic kidney disease

23. 1/28/2015 OBESITY 23

24. Reference: Textbook of Pathoogy –Harsh M ohan 1/28/2015 OBESITY 24

25. Thank you 1/28/2015 OBESITY 25