Caffeine's effect on the brain's adenosine receptors visualized for the first time

In continuation on my update on coffee

Molecular imaging with positron emission tomography (PET) has enabled scientists for the first time to visualize binding sites of caffeine in the living human brain to explore possible positive and negative effects of caffeine consumption. According to research published in the November issue of The Journal of Nuclear Medicine, PET imaging with F-18-8-cyclopentyl-3-(3-fluoropropyl)-1-propylxanthine (F-18-CPFPX) shows that repeated intake of caffeinated beverages throughout a day results in up to 50 percent occupancy of the brain's A₁adenosine receptors.

"There is substantial evidence that caffeine is protective against neurodegenerative diseases like Parkinson's or Alzheimer's disease," noted Elmenhorst. "Several investigations show that moderate coffee consumption of 3 to 5 cups per day at mid-life is linked to a reduced risk of dementia in late life. The present study provides evidence that typical caffeine doses result in a high A₁ adenosine receptor occupancy and supports the view that the A₁ adenosine receptor deserves broader attention in the context of neurodegenerative disorders." 

Caffeine's effect on the brain's adenosine receptors visualized for the first time

Caffeine can prevent memory loss in diabetes

Caffeine can prevent memory loss in diabetes: Badly controlled diabetes are known to affect the brain causing memory and learning problems and even increased incidence of dementia, although how this occurs is not clear. But now a study in mice with type 2 diabetes has discovered how diabetes affects a brain area called hippocampus causing memory loss, and also how caffeine can prevent this. 

Tea could help lower high blood pressure: Study

In continuation of my update on tea and its effect....

A new study suggests that taking tea daily could help in lowering blood pressure.The study shows that people who drank three cups of black tea a day were able to lower their blood pressure. This was seen when compared to those who drank a placebo similar in taste and caffeine content. Those who drank the tea saw a slight drop in both systolic and diastolic blood pressure over six months.

Experts however warned that drinking tea is not a substitute for blood pressure-lowering medication, but researchers said the findings show tea could still provide a benefit.

Researchers note that although the study cannot identify specific components of the tea that might lead to a drop in blood pressure, past studies have shown flavonoids, compounds found in many plants such as tea, are good for heart health.

“The message really isn't for an individual to go out and drink a lot of tea,” said Jonathan Hodgson,

More...

Maillard reaction is the principle contributor to the antioxidant capacity of coffee brews ......

Food scientists at the University of British Columbia have been able to pinpoint more of the complex chemistry behind coffee's much touted antioxidant benefits, tracing valuable compounds to the roasting process.  Yazheng Liu and Prof. David Kitts found that the prevailing antioxidants present in dark roasted coffee brew extracts result from the green beans being browned under high temperatures.

Liu and Kitts analyzed the complex mixture of chemical compounds produced during the bean's browning process, called the "Maillard reaction (a chemical reaction between an amino acid and a reducing sugar, usually requiring heat). The term refers to the work by French chemist Louis-Camille Maillard who in the 1900s looked at how heat affects the carbohydrates, sugars and proteins in food, such as when grilling steaks or toasting bread. Previous studies suggested that antioxidants in coffee could be traced to caffeine or the chlorogenic acid (see structures above and below respectively)  found in green coffee beans, but the present results clearly show that the Maillard reaction is the main source of antioxidants claims the researchers.  Researchers conclude that that coffee beans lose 90 per cent of their chlorogenic acid during the roasting process, LFS food science professor and director of the Food, Nutrition and Health program.

Ref : Yazheng Liu and David D. Kitt, Food Research International.