Pharmacology Capsaicinoids

Surh YJ, Ahn SH, Kim KC et al. (1995). Metabolism of capsaicinoids evidence for aliphatic hydroxylation and its pharmacological implications. Life Sci, 56, PL305-PL311. 

In the past few decades, the various activities such as antioxidant, cell inflammation, antimutagenic, and toxicity of capsaicinoid compounds have been investigated and reported by many researchers and scientists. Materska and Perucka reported the determination of the antioxidant activity of the capsaicinoid compounds isolated from hot and semi-hot pepper fruits at two different maturity stages during their cultivation [26], Reilly et al. have found that capsaicinoids are able to activate the vanilloid receptors, which are responsible for inflanunation and epithelial cell death in animal and human bodies [27,28]. The characteristic pharmacological responses of capsaicinoids include severe irritation, inflanunation, erythema, and transient hyper- and hypoalgesia at exposed sites such as, eyes, skin, nose, tongue, and respiratory tract. The vanilloid receptors are the calcium channel when activated by capsaicinoids they produce the characteristic sensations and causes toxicity in many mammalian cell types [27-29],... 

The high predominance of capsaicin in Capsicum fruits makes this alka-mide the most studied to evaluate the pharmacological activity of capsaicinoids. Capsaicin is also the capsaicinoid most widely used as pharmaceutical. 

The pharmacological mechanism of action of capsaicin has been extensively reviewed [78]. In 1997, Julius and coworkers isolated and cloned the molecular target of capsaicin, a cellular transmembrane protein and a nonselective cation-permeable pore region (channel) named transient receptor potential vanilloid subtype 1 (TRPVl, also known as vanilloid receptor for its interaction with capsaicinoids) [79]. The TRPVl receptor is found in primary afferent polymodal C-fibers and A8-fibers. C-Fibers are responsible for the burning sensations, while A8-fibers are responsible for the temperature (cold and hot), pressure (mechano), and pain sensations. Both fibers are located in... 

An exhaustive analysis of the structural implications of capsaicinoids on their metabolism by P450 enzymes and how they contribute to both detoxification and bioactivation processes in humans has been proposed. CycUzation, dehydrogenation to afford the terminal diene and imides, oxidatiOTi at the end of the carbon chain to render primary and tertiary alcohols, and demethylation and aromatic hydroxylation, are typical reactions in these processes, yielding metabolites with limited pharmacological and toxicological effects via reduction in their affinity for TRPVl [148]. 

Species of red peppers, or Capsicum (Solanaceae), are well-known as spicy ingredients in food, especially in tropical countries. The fruits contain a variable amount of highly pungent principles, the so-called capsaicinoids, which have the general structure iV-(4-hydroxy-3-methoxybenzyl)alkylamides (55). Suzuki and Iwai (186) have provided a recent introductory review. These compounds also have potent pharmacological properties. 

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