Caloric Restriction and Resveratrol Reverse a High-fat Diet Induced Diabetes and Improve Islet β cell Dysfunction in Mice Jiaoyue Zhang Ph.D Endocrinology Department,Union hospital, Huazhong University of Science & Technology, Wuhan , China

Caloric Restriction and Resveratrol Calorie restriction (CR), is basic for therapy of diabetes Calorie restriction (CR), based on low calorie intake, is basic for therapy of diabetes SIRT1 is the NAD + -dependent deacetylase, and controls the activities of genes that regulate circadian rhythm, apoptosis. SIRT1 is the NAD + -dependent deacetylase, and controls the activities of genes that regulate circadian rhythm, apoptosis. Resveratrol (Res), a type of natural phenol, is the potent natural SIRT1 activator. It has been found to lower plasma glucose in streptozotocin-induced diabetic rats. Resveratrol (Res), a type of natural phenol, is the potent natural SIRT1 activator. It has been found to lower plasma glucose in streptozotocin-induced diabetic rats.

SIRT1 is involved in the activities of β cell SIRT1 was preferentially expressed in pancreatic beta cells while not in exocrine cells SIRT1 was preferentially expressed in pancreatic beta cells while not in exocrine cells In beta cell-specific Sirt1-overexpressing (BESTO) transgenic mice ， GSIS ↑ ； In beta cell-specific Sirt1-overexpressing (BESTO) transgenic mice ， GSIS ↑ ； SIRT1 reduced by siRNA in beta cel lines (INS, MIN6) ， GSIS↓ SIRT1 reduced by siRNA in beta cel lines (INS, MIN6) ， GSIS↓ Our hypothesis ： SIRT1 could possibly play an important role in the effect of CR and Res on beta cell Our hypothesis ： SIRT1 could possibly play an important role in the effect of CR and Res on beta cell Bordone L, et al. PLoS Biol, 2006,4:e31 Moynihan KA, et al. Cell Metab, 2005,2:105-17

Aim of the research Explore the anti-hyperglycaemic role and mechanisms of CR and Res on beta cell protection Explore the anti-hyperglycaemic role and mechanisms of CR and Res on beta cell protection

male C57BL/6J mice control model standard chow ×24w Normal control High fat diet Large dosage of Res Low dosage of Res Caloric restriction NC HF CR R400 R High fat diet×8w standard chow +60%CR a high fat diet ×16w a high fat diet +Res400mg/kg/d a high fat diet +Res50mg/kg/d IPGTT Caloric intake 、 BW 、 lipid IPGTT 、 insulin 、 ITT 15 只 Obesity index ＝（ total fat weight ） /body weight×100

Compared to NC, *P<0.05 ， #P<0.01 ； compared to HF, △ P<0.05 ，▲ P<0.01 Caloric intake Body weight Blood FFA Obesity index # #▲#▲ #▲#▲ *▲*▲ #▲#▲ #▲#▲ # #

# * ▲ #▲#▲ # ▲ 8w 24w IPGTT curve FBG AUC # ▲ *△*△ ▲

Fasting blood insulin HOMA-IR Insulin tolerance (ITT) Ki ▲ #▲#▲ #▲#▲ # # #▲#▲ #▲#▲ #▲#▲ # ▲ #▲#▲ #▲#▲

Islet morphology NCR400 CRR50HF NC R400 CR R50HF Insulin protein expressions by immunohistochemistry (×400) HE stainig (×200)

Β cell mass Insulin content in pancreas ▲ #△#△ *▲*▲ # △△

ΔI30/ΔG30 Insulin stimulatory index * △ #▲#▲ #▲#▲ # #▲#▲ *▲*▲ ▲ ABC

NCHF CR R400 R50 Apoptosis by TUNEL (×200)

SIRT1 mRNA SIRT1 protein Marker NC HF CR R400 R50 UCP2 mRNA SIRT1 Marker NC HF CR R400 R50 NC HF CR R400 R50 # #▲#▲ * △ # #▲#▲ * △ # ▲▲ #▲#▲ UCP2 SIRT1

PDX-1 mRNA Bax mRNA Bcl-2 mRNA Marker NC HF CR R400 R50 PDX-1 Bcl-2 Marker NC HF CR R400 R50 GAPDH Bax # #▲#▲ # #▲#▲ ▲ ▲ ▲▲

MDA GSH-Px # ▲ ▲ *▲*▲ # ▲ #▲#▲ #▲#▲

Mitochondrial changes in islets （ electron microscopy ） NCHF CR R400 R50

CR and Res administration rendered the animals resistant to diet-induced obesity and insulin resistance, which was supported by previous studies. Importantly, the functions of GSIS in vivo and in vitro were improved robustly in HR group compared with NC and HF group in our experiment. CR and Res administration rendered the animals resistant to diet-induced obesity and insulin resistance, which was supported by previous studies. Importantly, the functions of GSIS in vivo and in vitro were improved robustly in HR group compared with NC and HF group in our experiment. Compared with CR ， Res does not affect caloric intake and sorts of food, less weight loss, lower blood glucose and less insulin sensitivity. Compared with CR ， Res does not affect caloric intake and sorts of food, less weight loss, lower blood glucose and less insulin sensitivity.

The role of beta cell protection Long term CR intervetion can inhibit compensary changes of islet β cell, and improve increased basal insulin secretion and impaired GSIS. It might be related to improved lipotoxicity and apoptosis. Long term CR intervetion can inhibit compensary changes of islet β cell, and improve increased basal insulin secretion and impaired GSIS. It might be related to improved lipotoxicity and apoptosis. Res also has β cell protection, especially in the capacity of insulin secretion. Res400mg/kg/d is more effective than 50mg/kg/d. Res also has β cell protection, especially in the capacity of insulin secretion. Res400mg/kg/d is more effective than 50mg/kg/d.

SIRT1 as a mediator of CR NAD + /NADH SIRT1 热卡限制 NAD + /NADH Visceral fat, liver, kidney and brain SIRT1 Anti-aging islet UCP2ATP GSIS 凋亡

Res increased SIRT1 expression on β cell only in higher dosage, but inhibited UCP2 in both groups. Res increased SIRT1 expression on β cell only in higher dosage, but inhibited UCP2 in both groups. The above role is still unclear especially in different tissues. The above role is still unclear especially in different tissues. The impact on UCP2 of Res might induce increased insulin secretion, and the role is independent on the expression of SIRT1. The impact on UCP2 of Res might induce increased insulin secretion, and the role is independent on the expression of SIRT1. Res impact on SIRT1 pathway Baur JA, et al. Nature, 2006, 444(7117): Lagouge M, et al.Cell, 2006, 127(6):

Both CR and Res can reverse diabetes induced by a high- fat diet. CR is more effective on insulin resistance. Res is more potent on blood glucose while not affecting caloric intake and body weight. Both CR and Res can reverse diabetes induced by a high- fat diet. CR is more effective on insulin resistance. Res is more potent on blood glucose while not affecting caloric intake and body weight. Both can improve beta cell dysfunction in secretion and morphology, and Res is more potent than CR. Both can improve beta cell dysfunction in secretion and morphology, and Res is more potent than CR. Conclusions

SIRT1 pathway might mediate the protective role of CR and Res on β cell ， but the effects on SIRT1 and UCP2 expressions are different. SIRT1 pathway might mediate the protective role of CR and Res on β cell ， but the effects on SIRT1 and UCP2 expressions are different. CR and Res do not affect PDX-1 mRNA expression ， but might improve Bcl-2/Bax imbalance and oxidative damage ， which induce improved mitochondrial damage and apoptosis CR and Res do not affect PDX-1 mRNA expression ， but might improve Bcl-2/Bax imbalance and oxidative damage ， which induce improved mitochondrial damage and apoptosis Conclusions