In high fat diet induced model would definitely provoke the insulin resistance in mice. I suggest to analyze few inflammatory mediators and cytokines other than biochemical parameters to know the changes occurred in the animals. However, the tissues should also be measured for the glucose transporter protein and the uptake of glucose by the tissues specially pancreatic cells. This would give you the clear picture if you want to study metabolic disorder such as type 2 diabetes.

Infact the obesity might play a significant role in the development of diabetes by altering lipid metabolism. May I suggest to determine the expression of protein in adipocytes and pancreatic tissues with the responsible glucose transporter protein such as GLUT 1,2,and 4 to get closer pictures of hyperlipidemia associated with diabetes.

yes, it is necessary

Root cause of insulin resistance is being obese.  Therefore, insulin resistance is one the important parameters that need to be measured in high fat diet induced obese mice. For this, you can measure any parameters as mentioned above, but I suggest you measure tumour necrosis factor alpha or any inflammatory mediators. 

Insulin resistance is the key for metabolic syndrome. Adiponectin is a useful biomarker, closely related with insulin resistance condition. Remember that you must use mice anti-insulin antibodies in your measurement of insulin. An inflammatory biomarker is  circulating high sensitivity CPR, . Quality Control measurements are quite necessary and also  a  sham operated control group.

It really depends on what you are studying. You haven't given any of the details of your study so it is difficult to judge. If you are suggesting that diet-induced obesity is involved in the development of ischemia, and you have evidence that the animals are hyperglycemic, it would seem like a logical and worthwhile experiment to do.

However if your study is focused on demonstrating a novel mechanism by which diet-induced obesity promotes ischemia (for example you have a knockout mouse that fails to develop ischemia in response to a high fat diet, and it also has high fasting glucose) then you probably don't need to do it.

@Guillaume de lartigue hfcd treated mice had lower infart after pMcao but post stroke recovery did not improve as compared to normal diet treated mice. My question is even when hfcd treated mice had higher fasting blood glucose as compared to normal diet, can i call hfcd treated group as diabetic? Or to prove they are diabetic i need to do insulin resistance test? I am just worried that reviewers should not ask us questions regarding hfcd mice are diabetic or obese.

It reported that mice would exhibited insulin resistance post HFD induced for 3 days. Body weight significantly increased after HFD induced for 3 weeks. you'd better check the diabetic phenotype of your HFD mice.

Hi Jatin, There's two separate issues that you're trying to address with one question. The fact that the HFD mice have fasting blood glucose is a good and I would do a glucose tolerance test to show they are also glucose intolerant. Ideally, the HFD mice will also have higher plasma insulin also. However, you could also do on insulin tolerance test to assess their insulin sensitivity. Showing the mice also have higher body mass and increased fat pad mass will also support your data.Hope this helps.

Hi Jatin, I agree with Rachael.

Not all high fat fed animals become diabetic, and those that do will develop diabetes at different time points. Since fasted hyperglycemia does mean the animals are diabetic, you will need to show it. You could do a simple glucose tolerance test to demonstrate that the animals are in fact glucose intolerant (diabetic). This is a good protocol if you are unsure how to do it - http://www.bio-protocol.org/e159.

Good luck.

I agree with the other comments, that you have to determine insulin resistance to demonstrate that your diet has been working. At first, if the mice on HFD become obese compared to chow fed mice, this is a first sign. We always do a glucose tolerance test and sometimes also add an insulin tolerance test. Another measure is to determine fat weight at sacrifice and to do insulin signalling on fasted mice (4-5 min insulin or saline injection at sacrifice). In the HFD fed mice you will observe in insulin target tissues (liver, muscle, adipose tissue) a reduction of Akt phosphorylation as well as the change of the phosphorylation status of other signalling proteins.