In recent years many researchers have examined the effects of plants used traditionally by indigenous healers and herbalists to support function and treat diseases. In most cases, scientist has confirmed the veracity traditional experience and wisdom by discovering the mechanism of action of these plants. Piper longum L. and Piper nigrum L.(Piperaceae) are used in Indian traditional medicine (Singh et al., 1992) and as a spice globally. Piperine (C17H19NO3), the alkaloid is responsible for the pungency of P. nigrum L. and P. longum L (Singh et al., 1992). Piperine can be obtained from the oleoresin in the peppercorns. Piperine makes up about 5-7% of the peppercorns. It exhibits a wide variety of biological effects.
Anti Inflammatory Activity
Indications & Usage
Piperine, in appropriate doses, may be useful in increasing the bioavailability of some drugs and nutrients. There is very preliminary evidence suggesting that piperine may aid in the digestion of food. There is also preliminary evidence that it may have some anticonvulsant, anticarcinogenic and anti-inflammatory properties. On the other hand, there is also preliminary evidence that it might be carcinogenic and cytotoxic in some circumstances and that it might interfere with reproductive processes and have negative effects on sperm. When applied topically, piperine shows antivitiligo activity.
The content of piperine in black pepper ranges from 5 to 9%. The daily consumption of piperine in populations that use black pepper regularly is approximately 17 to 31 milligrams daily.
Piperine is available in stand-alone supplements and in combination products. A typical dose is 5 mg daily.
Pregnant women and nursing mothers should avoid piperine supplementation.
Research & Summary
There are in vitro, animal and human studies demonstrating that piperine can significantly increase the bioavailability of numerous drugs and some nutritional supplements. Reportedly, it has demonstrated this effect with some antimicrobial, antiprotozoal, antihelmintic, antihistaminic, non-steroidal anti-inflammatory, muscle-relaxant and anticancer drugs, among others. It has also increased the bioavailability of coenzyme Q10, curcumin and beta-carotene.
In humans given 2-gram doses of curcumin alone, levels of curcumin in serum were undetectable to very low one hour post-administration. Concomitant administration of 20 mg of piperine was said to significantly increase absorption and bioavailability (by 2000%). Similar results were reported in rats.
In a double-blind crossover study, 5 mg of piperine daily for 14-day periods resulted in significant increases in serum beta-carotene levels. The same dose of piperine produced similar results in another study, this one involving coenzyme Q10.
The claim that piperine may aid in the digestion of food is based on some experimental animal data showing that dietary piperine seems to enhance pancreatic amylase lipase, trypsin and chymotrypsin activity.
Piperine may have some anticonvulsant activity comes, in part, from China, where the substance is used in an effort to treat some forms of epilepsy. In mice, piperine injected intraperitoneally inhibited clonic convulsions induced by kainate. It did not significantly block seizure activity induced by L-glutamate, N-methyl-D-aspartate or guanidinosuccinate.
In a rat intestinal model, piperine was said to provide protection against oxidative changes induced by a number of chemical carcinogens. In another study, this one in vitro, piperine reportedly reduced the cytotoxicity of aflatoxin B1 in rat hepatoma cells.
Piperine exhibited significant anti-inflammatory activity in carageenan-induced rat paw edema and in some other experimental models of inflammation. In one animal study, piperine reduced liver lipid peroxidation, acid phosphatase and edema induced by carageenan.
On the negative side, piperine has shown some evidence of being mutagenic and potentially carcinogenic under some circumstances. It has reportedly given rise to mutagenic products on reaction with nitrites. This causes concern since nitrites and piperine may be consumed simultaneously. Risk might increase with high-dose piperine supplementation. In another study, piperine appeared to enhance the bioavailability of aflatoxin B1 in rat tissues. And in yet another study, piperine was found to be cytotoxic to cultured brain neurons. Piperine was said to be non-mutagenic, however, in a study examining effects of the substance on the germ cells of Swiss albino mice.
In a recent study utilizing albino rats, piperine, given at doses of 5 and 10 mg/kg body weight for 30 days, resulted (at the 10-mg/kg dose level) in significant reduction in the weights of testes and accessory sex organs as well as severe damage to seminiferous tubules. The 5-mg/kg dose resulted in partial degeneration of germ cells.
Decreased mating performance, decreased fertility and anti-implantation activity, along with some other adverse reproductive events, were observed in mice given very high doses of piperine.