Anti-diarrhoeal activity of a polyherbal formulation in rats and elucidation of its cellular mechanisms.

OBJECTIVE: The present study was aimed to study anti-diarrhoeal activity of a polyherbal formulation (PHF) in rats and elucidate its mechanism of action. MATERIALS AND METHODS: Anti-diarrhoeal activity of PHF was investigated using castor oil-induced diarrhoea, small intestinal transit and enteropooling models in rats. PHF was tested at 75, 150 and 300 mg/kg rat body weight. Loperamide was used as a reference control for in vivo studies. Anti-secretory action was evaluated against heat labile enterotoxin (from Escherichia coli) induced secretion in rat ileal loop model. The effect of PHF (12.5-100 µg/ml) on cAMP-dependent secretory activity was investigated against forskolin-induced cAMP release in HT-29 cells. RESULTS: PHF demonstrated significant (p≤0.05) anti-diarrhoeal activity by increasing the time for first faecal drop and inhibited diarrhoeal episodes by 43, 58 and 60% at 75, 150 and 300 mg/kg body weight, respectively in a dose-dependent manner. Also, the intestinal transit was inhibited upto 33% and the weight of secretory contents induced by castor oil was significantly reduced by PHF, approximately 29% in enteropooling assay. On the other hand, the intestinal loop instilled with PHF and enterotoxin from E. coli demonstrated 61% inhibition of fluid accumulation as compared to loop instilled with enterotoxin only. In vitro studies indicated that PHF inhibits cAMP release in HT-29 cells corroborating the anti-secretory effects observed in aforesaid studies. CONCLUSION: The results suggest that the PHF possesses anti-diarrhoeal activity, evident through reduced faecal output, decreased intestinal transit and anti-secretory activities.

Polar extract of Curcuma longa protects cartilage homeostasis: possible mechanism of action.

BACKGROUND: Curcuma longa has been well documented for managing joint inflammation and pain. The present study investigated the effect of polar extract of C. longa (NR-INF-02) on cartilage homeostasis in human articular chondrocytes knee (NHAC-kn) cells to understand its plausible mechanism of action. METHODS: Dysregulation of cartilage homeostasis was induced by IL-1ß and H2O2. Modulating effects of NR-INF-02 on degradation markers viz., chondrocyte apoptosis, senescence, cytokine, eicosanoids, and cartilage synthesis markers viz., glycosaminoglycans and type II collagen degradation was evaluated in human articular chondrocytes knee (NHAC-kn) cells. Further, the effect of NR-INF-02 on lipopolysaccharide (LPS)-induced expression of NF-kB in RAW264.7 macrophages was investigated. RESULTS: NR-INF-02 significantly attenuated IL-1ß-induced chondrocyte cytotoxicity, apoptosis and release of chondrocyte degradation markers such as IL-6, IL-8, COX-2, PGE2, TNF-α, ICAM-1 in NHAC-kn cells. Also, NR-INF-02 protected IL-1ß-induced damage to synthesis markers such as glycosaminoglycans, type II collagen and further attenuated H2O2-induced chondrocyte senescence. In addition NR-INF-02 suppressed LPS-induced NF-kB expression in RAW264.7 cells. CONCLUSIONS: NR-INF-02 protects cartilage homeostasis by maintaining the balance between synthesis and degradation of cartilage matrix.

Is Andrographis paniculata extract and andrographolide anaphylactic?

Andrographis paniculata, "King of bitters" is a popularly known medicinal plant extensively used in many parts of the world for treatment of various diseases. Since recent past, anaphylactic/allergic type adverse events were reported upon A. paniculata usage, the study aimed to evaluate the anaphylactic and anaphylactoid potential of A. paniculata extract and andrographolide (a major phytoactive of A. paniculata). The anaphylactic potential was evaluated using active systemic anaphylaxis (ASA) assay in guinea pigs. Further, the release of allergic mediators was measured in immunoglobulin E (IgE) sensitized and non-IgE sensitized Rat Basophilic Leukemia (RBL-2H3) cell lines in-vitro. A. paniculata extract or andrographolide sensitized guinea pigs following the challenge antigen administration orally and intravenously did not demonstrate any clinical signs of anaphylaxis. IgE sensitized and non- IgE sensitized RBL-2H3 cells treated with A. paniculata extract did not induce release of allergic mediators. Whereas IgE sensitized and non- IgE sensitized RBL-2H3 cells treated with andrographolide demonstrated mild to moderate release of allergic mediators. A. paniculata extract has no anaphylactic and anaphylactoid potential in in-vivo and in-vitro studies. Whereas, andrographolide effects on allergic mediators in in-vitro studies needs to be scrutinized if they are of biologically important.

Safety evaluation of turmeric polysaccharide extract: assessment of mutagenicity and acute oral toxicity.

Curcuma longa Linn. (Zingiberaceae) commonly known as turmeric has long been used for centuries as a spice and household remedy. The present study was carried out to assess the possible mutagenic potential and acute oral toxicity of polysaccharide extract of turmeric rhizome (NR-INF-02) using standard tests. The standard battery of in vitro genotoxicity tests, bacterial reverse mutation test (BRMT), chromosome aberration (CA), and micronucleus (MN) tests were employed to assess the possible mutagenic activity of NR-INF-02 (Turmacin). The results showed no mutagenic effect with NR-INF-02 up to a dose of 5000 µg/mL in BRMT. The results on CA and MN tests revealed the non clastogenic activity of NR-INF-02 in a dose range of 250.36 to 2500 µg/mL with and without metabolic activation (S9). In acute oral toxicity study, NR-INF-02 was found to be safe up to 5 g/kg body weight in Wistar rats. Overall, results indicated that polysaccharide extract of C. longa was found to be genotoxically safe and also exhibited maximum tolerable dose of more than 5 g/kg rat body weight.