Inflammatory bowel diseases (IBD) like Crohn’s disease and Ulcerative colitis are a major economic burden. The ages of onset for these indications are typically between 15 to 30 years (with approximately 10% individuals under 18 years of age). IBDs usually follow a relapsing-remitting course, with periods of acute illness followed by periods of long remission. According to latest estimates from the CDC, approximately 1.4 million Americans are currently suffering from inflammatory bowel conditions.
It has been observed that these disorders have a multifactorial origin of occurrence. Certain key factors like impaired defense mechanisms, lack of antioxidants, and overproduction of irritants and free radicals may play a significant role in the disease pathogenesis. Most current regimens focus at improving the gut environment to reduce the frequency of exacerbations.
Recently, scientists have initiated a new study to test the efficacy of Gymnema sylvestre (GS) in the prevention of ulcerative colitis symptoms (in response to acetic acid exposure) in Wistar rats. An extract from Gymnema sylvestre (GS) leaves has long been recognized for its therapeutic benefits and medicinal properties. When introduced in the human body, it helps in normalizing serum glucose concentration and controlling inflammatory or oxidative damage to cells.
Details of the experiment:
As part of the experiment, the research scientists exposed the rats to three different doses (i.e. 50, 100, 200 mg/kg/day) of GS leaves extract for 7 days, with single 300 mg/kg/day dose of mesalazine. Investigators then introduced ulcerative colitis lesions in the gut of Wistar rats by exposing the gut cells to acetic acid.
The research team waited for 24 hours (1 day) after which the animals were sacrificed to study the colonic tissue.
Specific techniques like Alcian blue dye was used to analyze the total content of mucus cells in the colon; along with the content of several other oxidative enzymes and free radicals like; tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), interleukin-1 beta (IL-1beta), and prostaglandin E2 (PGE2); all of which are recognized pro-inflammatory cytokines along with concentration of nitric oxide (NO) in the colonic tissues.
In addition, protective antioxidant enzymes naturally present in the gut were also analyzed, such as catalase (CAT) and superoxide dismutase (SOD), in addition to the non-protein sulfhydryl group (NPSH), the total glutathione sulfhydryl group (T-GSH), and thiobarbituric acid reactive substances (TBARS).
The scientists also studied the changes that took place in the tissues at the microscopic level.
Results of the study:
After analyzing the tissues, scientists observed that exposure to acetic acid increases the tissue concentration of thiobarbituric acid reactive substances (TBARS), while at the same time decreases the colonic concentration of natural antioxidant like CAT, NP-SH, T-GSH and SOD.
However, after GS pretreatment, the results were different even after AA exposure. This includes inhibition of the mucus content and elevation of TBARS. The rats were also observed to have low levels of NP-SH and T-GSH. Additionally, the antioxidant enzyme concentration improved back to normal (of SOD and CAT) after GS supplementation. It was also observed that AA exposure was followed by reduction in RNA, DNA and TP levels; but the effects subsided after GS administration. Same is true for the inhibition of the elevations in the enzyme secretion of PGE2 and NO levels in colonic tissues (and other pro-inflammatory cytokines).
The research team concluded that GS extract can be potentially tested as an effective remedy for the management of UC symptoms in human subjects due to its anti-inflammatory and anti-oxidant behavior in biological tissues.