A new study has said that pycnogenol, an antioxidant plant extract from the bark of the French maritime pine tree, can counteract kidney damage caused by hypertension.
"Kidney disease is a common problem for people with hypertension and is an equally 'silent' threat to the body. There are no warning signals and inefficient fluid removal may further increase the blood pressure, causing a vicious circle to set in," said Dr. Gianni Belcaro, a lead researcher of the study.
"The results of this study demonstrated Pycnogenol's ability not only to reduce blood pressure, but also to relieve the kidney damage caused by chronic hypertension," Belcaro added.
The randomized, controlled study conducted by the G D'Annunzio University in Italy investigated 55 hypertensive patients who showed early signs of impaired kidney function, as judged by elevated amounts of proteins found in their urine.
The patients were divided into two groups. Both groups were treated with anti-hypertensive medication Ramipril and one group of 29 patients took Pycnogenol in addition to the Ramipril. Urine was collected during a 24 hour period for quantification of protein (albumin) at baseline and again after six months of treatment.
All patients included in the study had an average urinary protein level of 89 mg per 24-hour period, significantly exceeding the 30 mg measure, up to which kidney function is considered sufficient.
After six months of treatment with Ramipril, average protein levels decreased to 64 mg per 24-hour period, remaining well above an acceptable level.
On the other hand, the group taking Pycnogenol as an adjunct to Ramipril had an average of only 39 mg per 24-hour period, a decrease of nearly double compared with anti-hypertensive medication taken alone.
The study also found a statistically significant decrease in patients' blood pressure when taking Pycnogenol in conjunction with Ramipril. When treated exclusively with Ramipril, systolic blood pressure values dropped by more than 30 percent and diastolic blood pressure values dropped approximately eight percent.
The addition of Pycnogenol decreased both systolic and diastolic pressures by an additional three to six percent. Pycnogenol was also found to lower the patients' elevated levels of inflammatory marker CRP, a blood protein associated with the risk for acute cardiovascular events such as heart attack, reducing values to a healthy level.
The study has been published in the March 2010 issue of the Journal of Cardiovascular Pharmacology and Therapeutics.