Prophylactic and therapeutic effects of n-3 polyunsaturated fatty acids, capsaicin, and curcumin on adjuvant induced arthritis in rats

Growth Performance, Metabolomics, and Microbiome Responses of Weaned Pigs Fed Diets Containing Growth-Promoting Antibiotics and Various Feed Additives

The objective of this study was to determine the potential biological mechanisms of improved growth performance associated with potential changes in the metabolic profiles and intestinal microbiome composition of weaned pigs fed various feed additives. Three separate 42 day experiments were conducted to evaluate the following dietary treatments: chlortetracycline and sulfamethazine (PC), herbal blends, turmeric, garlic, bitter orange extract, sweet orange extract, volatile and semi-volatile milk-derived substances, yeast nucleotide, and cell wall products, compared with feeding a non-supplemented diet (NC). In all three experiments, only pigs fed PC had improved (p < 0.05) ADG and ADFI compared with pigs fed NC. No differences in metabolome and microbiome responses were observed between feed additive treatments and NC. None of the feed additives affected alpha or beta microbiome diversity in the ileum and cecum, but the abundance of specific bacterial taxa was affected by some dietary treatments. Except for feeding antibiotics, none of the other feed additives were effective in improving growth performance or significantly altering the metabolomic profiles, but some additives (e.g., herbal blends and garlic) increased (p < 0.05) the relative abundance of potentially protective bacterial genera that may be beneficial during disease challenge in weaned pigs.

The Effect of Capsaicin on Growth Performance, Antioxidant Capacity, Immunity and Gut Micro-Organisms of Calves

Capsaicin is the active ingredient of the red pepper plant of the genus Capsicum. The aim of this study was to investigate the effects of different doses of capsaicin on growth performance, antioxidant capacity, immunity, fecal fermentation parameters and gut microbial composition in nursing calves. Twenty-four newborn Holstein calves were randomly assigned to three treatment groups, which each consisted of eight calves. The milk replacer was supplemented with 0, 0.15 or 0.3 mL/d of capsaicin in each of the three treatment groups. During the 4-week experiment, intake was recorded daily, body weight and body size parameters were measured at the beginning and end of the trial and serum samples and rectal fecal samples were collected at the end of the trial to determine serum parameters, fecal fermentation parameters and fecal microbiome compartments. The results showed that both doses of capsaicin had no negative effect on the growth performance or the fecal fermentation parameters of calves, and the higher dose (0.3 mL/d) of capsaicin significantly improved the antioxidant capacity and immunity of calves. The calves in the high-dose capsaicin-treated group had lower fecal scores than those recorded in the control group. High doses of capsaicin increased glutathione antioxidant enzyme, superoxide dismutase, immunoglobulin A, immunoglobulin G, immunoglobulin M and interleukin-10 levels and decreased malondialdehyde and bound bead protein levels. In addition, capsaicin regulated the gut microbiota, reducing the abundance of diarrhea-associated bacteria, such as Eggerthella, Streptococcus, Enterococcus and Enterobacteriaceae, in the gut of calves in the treated group. Therefore, high doses of capsaicin can improve the antioxidant and immune capacity of calves without affecting growth performance, as well as improve the gut microbiological environment, which enables the healthy growth of calves.

A review of therapeutic potentials of turmeric (Curcuma longa) and its active constituent, curcumin, on inflammatory disorders, pain, and their related patents

Turmeric (Curcuma longa) and its constituent, curcumin, have been used for their therapeutic properties for a long time. Most of the medicinal impacts of turmeric and curcumin might be attributed to their anti-inflammatory, antinociceptive, and antioxidant effects. In the present review, the preventive and therapeutic potentials of turmeric and its active constituent, curcumin, on inflammatory disorders and pain as well as patents related to their analgesic and anti-inflammatory effects, have been summarized to highlight their value on human health. A literature review was accomplished in Google Scholar, PubMed, Scopus, Google Patent, Patentscope, and US Patent. Several documents and patents disclosed the significance of turmeric and curcumin to apply in several therapeutic, medicinal, and pharmaceutical fields. These phytocompounds could be applied as a supplementary therapy in phytotherapy, inflammatory disorders such as arthritis, inflammatory bowel diseases, osteoarthritis, psoriasis, dermatitis, and different types of pain including neuropathic pain. However, because of inadequate clinical trials, further high-quality studies are needed to firmly establish the clinical efficacy of the plant. Consistent with the human tendency to the usage of phytocompounds rather than synthetic drugs, particular consideration must be dedicated to bond the worth of turmeric and curcumin from basic sciences to clinical applications.

Experimental and clinical reports on anti-inflammatory, antioxidant, and immunomodulatory effects of Curcuma longa and curcumin, an updated and comprehensive review

Curcuma longa (C. longa) or turmeric is a plant with a long history of use in traditional medicine, especially for treating inflammatory conditions C. longa and its main constituent, curcumin (CUR), showed various pharmacological effects such as antioxidant and anti-microbial properties. The updated knowledge of anti-inflammatory, antioxidant, and immunomodulatory effects of C. longa and CUR is provided in this review article. Pharmacological effects of C. longa, and CUR, including anti-inflammatory, antioxidant, and immunomodulatory properties, were searched using various databases and appropriate keywords until September 2020. Various studies showed anti-inflammatory effects of C. longa and CUR, including decreased white blood cell, neutrophil, and eosinophil numbers, and its protective effects on serum levels of inflammatory mediators such as phospholipase A2 and total protein in different inflammatory disorders. The antioxidant effects of C. longa and CUR were also reported in several studies. The plant extracts and CUR decreased malondialdehyde and nitric oxide levels but increased thiol, superoxide dismutase, and catalase levels in oxidative stress conditions. Treatment with C. longa and CUR also improved immunoglobulin E (Ig)E, pro-inflammatory cytokine interleukin 4 (IL)-4, transforming growth factor-beta, IL-17, interferon-gamma levels, and type 1/type 2 helper cells (Th1)/(Th2) ratio in conditions with disturbance in the immune system. Therefore C. longa and CUR showed anti-inflammatory, antioxidant, and immunomodulatory effects, indicating a potential therapeutic effect of the plant and its constituent, CUR, for treating of inflammatory, oxidative, and immune dysregulation disorders.

Toxicokinetic Study of a Gastroprotective Dose of Capsaicin by HPLC-FLD Method

BACKGROUND

A low dose of capsaicin and its natural homologs and analogs (capsaicinoids) have shown to prevent development of gastric mucosal damage of alcohol and non-steroid anti-inflammatory drugs. Based on this experimental observation, a drug development program has been initiated to develop per os applicable capsaicin containing drugs to eliminate gastrointestinal damage caused by non-steroid anti-inflammatory drugs.

METHODS

As a part of this program, a sensitive and selective reverse-phase high-performance liquid chromatography-based method with fluorescence detection has been developed for quantification of capsaicin and dihydrocapsaicin in experimental dog's plasma.

RESULTS

The method was evaluated for a number of validation characteristics (selectivity, repeatability, and intermediate precision, LOD, LOQ, and calibration range). The limit of detection (LOD) was 2 ng/mL and the limit of quantification (LOQ) was 10 ng/mL for both capsaicin and dihydrocapsaicin. The method was used for analysis of capsaicin and dihydrocapsaicin in the plasma samples obtained after per os administration of low doses (0.1, 0.3, and 0.9 mg/kg bw) of Capsaicin Natural (USP 29) to the experimental animals.

CONCLUSIONS

The obtained results indicated that the administered capsaicinoids did not reach the general circulation.

Biological Activities of Red Pepper (Capsicum annuum) and Its Pungent Principle Capsaicin: A Review

Capsaicin, the pungent alkaloid of red pepper (Capsicum annuum) has been extensively studied for its biological effects which are of pharmacological relevance. These include: cardio protective influence, antilithogenic effect, antiinflammatory, and analgesia, thermogenic influence, and beneficial effects on gastrointestinal system. Therefore, capsaicinoids may have the potential clinical value for pain relief, cancer prevention and weight loss. It has been shown that capsaicinoids are potential agonists of capsaicin receptor (TRPV1). They could exert the effects not only through the receptor-dependent pathway but also through the receptor-independent one. The involvement of neuropeptide Substance P, serotonin, and somatostatin in the pharmacological actions of capsaicin has been extensively investigated. Topical application of capsaicin is proved to alleviate pain in arthritis, postoperative neuralgia, diabetic neuropathy, psoriasis, etc. Toxicological studies on capsaicin administered by different routes are documented. Capsaicin inhibits acid secretion, stimulates alkali and mucus secretion and particularly gastric mucosal blood flow which helps in prevention and healing of gastric ulcers. Antioxidant and antiinflammatory properties of capsaicin are established in a number of studies. Chemopreventive potential of capsaicin is evidenced in cell line studies. The health beneficial hypocholesterolemic influence of capsaicin besides being cardio protective has other implications, viz., prevention of cholesterol gallstones and protection of the structural integrity of erythrocytes under conditions of hypercholesterolemia. Beneficial influences of capsaicin on gastrointestinal system include digestive stimulant action and modulation of intestinal ultrastructure so as to enhance permeability to micronutrients.

Therapeutic uses ofCurcuma longa (turmeric)

Curcuma longa commonly known as tumeric is traditionally used as a spice in Indian food. A wide range of biological activities e.g. anticancer, antimicrobial, antiinflammatory and free radical scavenging activity of the plant suggests a logical basis for its traditional use in foodstuff. Various phytothreapeutic uses ofCurcuma longa have been reviewed.

Studies on the in vitro absorption of spice principles – Curcumin, capsaicin and piperine in rat intestines

A comparative evaluation of the absorbability of three structurally similar and physiologically active spice principles in an in vitro system consisting of everted rat intestinal sacs was made. When everted sacs of rat intestines were incubated with 50-1000 microg of curcumin in 10 ml incubation medium, absorption of the spice principle was maximum at 100 microg concentration. The amount of absorbed curcumin present in the serosal fluid was negligible. This and the comparatively lower recovery of the original compound suggested that curcumin to some extent undergoes a modification during absorption. For similar concentrations of added piperine, about 44-63% of piperine disappeared from the mucosal side. Absorption of piperine which was maximum at 800 microg per 10 ml was about 63%. The absolute amounts of piperine absorbed in this in vitro system exceeded the amounts of curcumin. The absorbed piperine could be traced in both the serosal fluid and in the intestinal tissue, indicating that piperine did not undergo any metabolic change during the process of absorption. 7-12% of the absorbed piperine was found in the serosal fluid. When everted sacs of rat intestines were incubated with 10-500 microg of capsaicin, a maximum of 82-88% absorption could be seen in the lower concentrations, and the amount of absorbed capsaicin did not proportionately increase at higher concentrations. A relatively higher percentage of the absorbed capsaicin could be seen in the serosal fluid as compared to curcumin or piperine. When these spice active principles were associated with mixed micelles, their in vitro intestinal absorption was relatively higher. Curcumin absorption in everted intestinal sac increased from 48.7% to 56.1% when the same was present in micelles. In the case of capsaicin and piperine, increase in absorption was 27.8-44.4% and 43.4-57.4%, respectively, when they were present in micelles as compared to its native form.

Influence of curcumin, capsaicin, and piperine on the rat liver drug-metabolizing enzyme system in vivo and in vitro

The effect of dietary supplementation of spice-active principles, curcumin (0.2%), capsaicin (0.015%), and piperine (0.02%) on the activities of the liver drug-metabolizing enzyme system was examined. All the 3 dietary spice principles significantly stimulated the activity of aryl hydroxylase. A synergistic action of dietary curcumin and capsaicin with respect to stimulating the activity of aryl hydroxylase was also evidenced when fed in combination. The activity of N-demethylase essentially remained unaffected by dietary curcumin, capsaicin, or their combination, but was significantly lowered as a result of piperine feeding. Uridine dinucleotide phosphate (UDP)-glucuronyl transferase activity was decreased by dietary piperine and the combination of curcumin and capsaicin. NADPH-cytochrome c reductase activity was significantly decreased by dietary piperine. The levels of hepatic microsomal cytochrome P450 and cytochrome b5 were not influenced by any of the dietary spice-active principles. These spice-active principles were also examined for their possible in vitro influence on the components of the hepatic drug-metabolizing enzyme system in rat liver microsomal preparation. Piperine significantly decreased the activity of liver microsomal aryl hydroxylase activity when included in the assay medium at 1 x 10(-6) mol/L, 1 x 10(-5) mol/L, and 1x 10(-4) mol/L level. Lowered activity of N-demethylase was observed in presence of capsaicin or piperine at 1 x 10(-6) mol/L in the assay medium. Hepatic microsomal glucuronyl transferase activity was significantly decreased in vitro by addition of capsaicin or piperine. Capsaicin and piperine brought about significant decrease in liver microsomal cytochrome P450 when included at 1 x 10(-6) mol/L and 1 x 10(-5) mol/L, the effect being much higher in the case of piperine. The results suggested that whereas the 3 spice principles have considerable similarity in structure, piperine is exceptional in its influence on the liver drug-metabolizing enzyme system. The study also indicated that a combination of curcumin and capsaicin does not produce any significant additive effect on the liver drug-metabolizing enzyme system.

Protective effect of dietary curcumin and capsaicin on induced oxidation of low-density lipoprotein, iron-induced hepatotoxicity and carrageenan-induced inflammation in experimental rats

The beneficial influence of dietary curcumin, capsaicin and their combination on the susceptibility of low-density lipoprotein (LDL) to oxidation was examined in an animal study. Individually, both dietary curcumin and capsaicin significantly inhibited the in vivo iron-induced LDL oxidation, as well as copper-induced oxidation of LDL in vitro. The protective effect of the combination of curcumin and capsaicin on LDL oxidation was greater than that of individual compounds. This protective influence of spice principles was also indicated by the relative anodic electrophoretic mobility of oxidized LDL on agarose gel. In another study, rats injected with iron showed hepatic toxicity as measured by an increase in lipid peroxides and elevated serum enzymes, alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase. Dietary curcumin, capsaicin and their combination reduced the activities of these enzymes, and lowered the liver lipid peroxide level, indicating amelioration of the severity of iron-induced hepatotoxicity. In yet another study, a comparison of the extent of carrageenan-induced paw inflammation showed that both dietary curcumin and capsaicin moderately lowered inflammation, while the spice principles in combination were more effective. Dietary curcumin and capsaicin significantly decreased the activity of 5'-lipoxygenase activity in the polymorphonuclear lymphocytes in carrageenan-injected rats, the decrease being even higher in the case of combination of these two spice principles. Results suggest that dietary curcumin and capsaicin individually are protective to LDL oxidation both in vivo and in vitro, to iron-induced hepatotoxicity and to carrageenan-induced inflammation. This beneficial effect was higher when the two compounds were fed in combination.

Biological properties of curcumin-cellular and molecular mechanisms of action

Curcuminoids, a group of phenolic compounds isolated from the roots of Curcuma longa (Zingiberaceae), exhibit a variety of beneficial effects on health and on events that help in preventing certain diseases. A vast majority of these studies were carried out with curcumin (diferuloyl methane), which is a major curcuminoid. The most detailed studies using curcumin include anti-inflammatory, antioxidant, anticarcinogenic, antiviral, and antiinfectious activities. In addition, the wound healing and detoxifying properties of curcumin have also received considerable attention. As a result of extensive research on the therapeutic properties of curcumin, some understanding on the cellular, molecular, and biochemical mechanism of action of curcumin is emerging. These findings are summarized in this review.

Signal transduction for inhibition of inducible nitric oxide synthase and cyclooxygenase-2 induction by capsaicin and related analogs in macrophages

1. Although capsaicin analogs might be a potential strategy to manipulate inflammation, the mechanism is still unclear. In this study, the effects and action mechanisms of vanilloid analogs on iNOS and COX-2 expression were investigated in RAW264.7 macrophages. 2. Capsaicin and resiniferatoxin (RTX) can inhibit LPS- and IFN-gamma-mediated NO production, and iNOS protein and mRNA expression with similar IC50 values of around 10 microm. 3. Capsaicin also transcriptionally inhibited LPS- and PMA-induced COX-2 expression and PGE2 production. However, this effect exhibited a higher potency (IC50: 0.2 microm), and RTX failed to elicit such responses at 10 microm. 4. Interestingly, we found that capsazepine, a competitive TRPV1 antagonist, did not prevent the inhibition elicited by capsaicin or RTX. Nevertheless, it mimicked vanilloids in inhibiting iNOS/NO and COX-2/PGE2 induction with an IC50 value of 3 microm. RT-PCR and immunoblotting analysis excluded the expression of TRPV1 in RAW264.7 macrophages. 5. The DNA binding assay demonstrated the abilities of vanilloids to inhibit LPS-elicited NF-kappaB and AP-1 activation and IFN-gamma-elicited STAT1 activation. The reporter assay of AP-1 activity also supported this action. 6. The kinase assay indicated that ERK, JNK, and IKK activation by LPS were inhibited by vanilloids. 7. In conclusion, vanilloids can modulate the expression of inflammatory iNOS and COX-2 genes in macrophages through interference with upstream signalling events of LPS and IFN-gamma. These findings provide new insights into the potential benefits of the active ingredient in hot chilli peppers in inflammatory conditions.

A sardine oil-rich diet increases iron absorption but does not compensate the hypoferremia associated with inflammation

Inflammatory disorders are associated with a decrease in iron absorption because of the blockade of iron in storage organs. Fish oils, rich in n-3 PUFA, are used to prevent and treat inflammatory disorders and increase iron absorption in noninflamed rats. Here we examine whether n-3 PUFA prevent inflammation-related hypoferremia. Two groups of rats were fed isoenergetic semipurified diets (a standard diet and a sardine oil-rich diet). A carrageenan granuloma was induced in half of the rats of each dietary group. Ferrokinetic studies using 59Fe, hematological analyses, and iron store evaluation were performed in noninflamed and inflamed rats. Although dietary n-3 PUFA increased 59Fe absorption in carageenan-treated rats, they did not restore the hypoferremia associated with inflammation, which is due to several mechanisms. Among these mechanisms, the blockade of iron in storage organs is relevant. However, this blockade was less evident in the spleen of inflamed rats fed the sardine oil diet.

The effect of fish oil on bone resorption following pulp exposure in rats

The aim of this study was to determine whether treatment with fish oil may alter the periapical bone resorption following pulp exposure in rats. Untreated and pulp-exposed animals served as the negative and positive control, respectively. Other pulp-exposed animals were orally treated with fish oil at different concentrations and frequencies. Periapical tissue sections were stained with tartrate-resistant acid phosphatase (TRAP), and then the numbers of both periapical osteodasts and preosteoclasts were determined. The levels of bone resorption were assessed using the osteoclast-bone interface (OBI) index. The results showed that no differences between the numbers of both osteoclasts and preosteoclasts in the fish oil-treated animals and the negative control at day 14 could be found. Similarly, the periapical bone resorption in the animals treated with fish oil for 14 days significantly reduced to the levels of that in the negative control. The results of the present study, therefore, suggest that oral treatment with fish oil may inhibit bone resorption following pulp exposure in rats and hence, may have a therapeutic modality for inflamed periradicular tissue.