Wound healing activity of Glycosmis arborea leaf extract in rats

Ethnopharmacological relevance

Glycosmis arborea Roxb, syn. Glycosmis pentaphylla Retz, (Rutacea) is a shrub found all over India, have been used for the healing of wounds of livestock in Indian folk medicine.

Aim of the study

The present study provides a scientific evaluation for the wound healing potential of ethanolic extract of Glycosmis arborea leaves.

Methods and materials

Excision and incision wounds were inflicted upon four groups containing six rats each. Group-1 was assigned as control (ointment base), Group-2 and Group-3 were treated with 5 and 10% EtOH extract ointment. Group-4 was treated with standard Nitrofurazone (0.2%) ointment. The parameters observed were percentage of wound contraction, epithelization period, tensile strength, hydroxyproline content. Ethanolic extract of Glycosmis arborea leaves was given orally at a dose of 200, 400 mg/kg/day in dead space wound model.

Results

Topical application of Glycosmis arborea ointment (10%) in excision wound model significantly (P < 0.05) increased the percentage of wound contraction (96.91%) compared with control (60.27%) and decreased the epithelization time. The tensile strength significantly (P < 0.05) increased in Group-3 at 560.33 ± 6.48 g when compared to control at 319.17 ± 6.16 g. Rats treated with Glycosmis arborea extract (400 mg/kg) showed significant (P < 0.05) increase in hydroxyproline content at 54.94 ± 0.96 mg/g when compared with control at 30.77 ± 1.13 mg/g.

Conclusion

The ethanolic extract of Glycosmis arborea facilitated wound healing significantly, corroborating the folk medicinal use of this plant.     

Hepatoprotective activity of the edible snail (Bellamia bengalensis) flesh extract in carbon tetrachloride induced hepatotoxicity in rats

Ethnopharmacological relevance

In the folk-traditional medicine, snails were used to purify blood, boost immune system, prevent conjunctivitis and to treat liver problems.

Objectives

To evaluate the hepatoprotective activity of the edible snail (Bellamia bengalensis) flesh extract in male Wistar rats treated with carbon tetrachloride as an hepatotoxicant.

Materials and methods

Live adult Bellamia bengalensis was collected commercially from the Kolkata market. Aqueous flesh extract (BBE) was prepared in 0.9% saline and expressed in terms of wet weight basis. The aqueous flesh extract was administered orally (1, 2 g kg⁻¹ day⁻¹) to male rats for 12 days. Liv52 was used as positive control. 24 h after administration of extract, the rats were given a single oral dose of CCl₄ (1.25 ml kg⁻¹), except vehicle control rats. After 24 h of CCl₄ administration, all the animals were sacrificed to collect the blood and liver tissue.

Results

BBE (1 and 2 g kg⁻¹ day⁻¹, p.o. × 12 days) significantly prevented CCl₄ induced elevation of SGOT, SGPT, γGT, ACP, ALP, bilirubin, LDH and CCl₄ induced decrease in total protein, triglyceride level in male Wistar rats. BBE treated rat liver anti-oxidant parameters (LPO, SOD, GSH, CAT, GPx) were significantly antagonized for the pro-oxidant effect of CCl₄. Histopathological studies also supported the protective effect of BBE.

Conclusion

This study validated the folk and traditional use of snail in liver disorder through CCl₄-induced rat experimental model.     

Antiplasmodial and cytotoxic activities of medicinal plants traditionally used in the village of Kiohima, Uganda

Aim of the study

In Uganda, malaria is the most common disease and Ugandan people largely rely on traditional medicine. In this context, we carried out an ethnobotanical study on the Kiohima village, located close to the Kibale National Park in South-Western Uganda and investigated in vitro the antiplasmodial and cytotoxic activities of selected medicinal plants.

Materials and methods

Seventy-five plants-using adults (men and women) were interviewed to find out their plant use. From these information, 48 plants used in traditional medicine were identified and according to their reported uses and to bibliographic data, several parts of 28 plants (leaves, barks, roots), were selected and collected for biological evaluations. These samples were dried, extracted with ethyl acetate and the crude extracts were assayed for in vitro antiplasmodial and cytotoxic activities at 10 μg/mL.

Results

One third of the screened plants showed a significant antiplasmodial activity with inhibition greater than 50% at 10 μg/mL.

Conclusion

These results may indicate a possible explanation of the use of some medicinal plant against malaria in the village of Kiohima and have also allowed to highlight a plant with potent antimalarial activity: Citropsis articulata root barks.     

Deciphering molecular mechanism underlying antileishmanial activity of Nyctanthes arbortristis, an Indian medicinal plant

Ethnopharmacological relevance

Nyctanthes arbortristis L. (Oleaceae) is widely used in the traditional medicine of India. The plant is shown to have antibacterial and antileishmanial activities.

Aim of the study

Evaluation of iridoid glucosides from the plant as inhibitor of trypanothione reductase (TryR), a validated drug target enzyme of the Leishmania parasite. The study contributes towards understanding mechanism of antileishmanial effect of the plant.

Materials and methods

TryR of Leishmania parasite is expressed and purified. Iridoid glucosides are isolated from the plant and tested as inhibitor of TryR enzyme of the parasite.

Results

Inhibitory constant (K_i) of various iridoid glucosides ranges from 3.24 ± 0.05 μM to 6.49 ± 0.05 μM. Thus, the molecular mechanism underlying antileishmanial activity of these compounds is mediated through inhibition of TryR.

Conclusion

The current study also points out towards potential application of iridoid glucosides as novel drugs against the disease.     

Involvement of p38 MAPK signaling pathway in the anti-melanogenic effect of San-bai-tang, a Chinese herbal formula, in B16 cells

Aim of the study

San-bai-tang (SBT), a Chinese herbal formula, is traditionally used as a skin whitener in China. In our previous screening assays, SBT was identified as an effective tyrosinase inhibitor. In this study, we aim to investigate the anti-melanogenic effect and mechanisms of SBT in B16 cells.

Materials and methods

Cell viability was examined by the MTT assay. Cellular tyrosinase activity and melanin content were determined using spectrophotographic methods. Protein expression was analyzed by immunoblotting.

Results

SBT inhibited tyrosinase activity with an IC₅₀ of 215.6 ± 10.3 μg/ml, and decreased cellular melanin content with an IC₅₀ of 254.8 ± 14.5 μg/ml at 48 h. MTT assay demonstrated that 48-h SBT (50-400 μg/ml) treatment did not show obvious cytotoxicity. Immunoblot analysis showed that SBT (100, 200 or 400 μg/ml) treatment for 48 h down-regulated the expression levels of phosphorylated-p38, MITF, tyrosinase, TRP-1 and TRP-2 in a dose-dependent manner.

Conclusions

SBT inhibited melanogenesis in B16 cells, and suppression of p38 MAPK signaling pathway contributed to the anti-melanogenic effect of SBT by down-regulating the expression of MITF and melanogenic enzymes. These novel findings demonstrated the anti-melanogenic effect and mechanisms of SBT, and provide pharmacological basis for the traditional use of SBT.     

Sida rhomboidea.Roxb leaf extract ameliorates gentamicin induced nephrotoxicity and renal dysfunction in rats

Ethnopharmacological relevance

Sida rhomboidea.Roxb (SR) known as “Mahabala” in Ayurveda and marketed as “Shahadeyi” is used in ethnomedicine to treat ailments such as dysuria and urinary disorders.

Aim of the study

To evaluate nephroprotective potential of SR against gentamicin (GM) induced nephrotoxicity and renal dysfunction.

Materials and methods

Nephrotoxicity was induced in rats with GM (100 mg/kg bodyweight (i.p.) for 8 days) and were treated with SR extract (200 and 400 mg/kg bodyweight (p.o.) for 8 days) or 0.5% carboxymethyl cellulose (vehicle). Plasma and urine urea and creatinine, renal enzymatic and non-enzymatic antioxidants along with lipid peroxidation were evaluated in various experimental groups.

Results

GM treatment induced significant elevation (p < 0.05) in plasma and urine urea, creatinine, renal lipid peroxidation along with significant decrement (p < 0.05) in renal enzymatic and non-enzymatic antioxidants. SR treatment to GM treated rats (GM + SR) recorded significant decrement (p < 0.05) in plasma and urine urea and creatinine, renal lipid peroxidation along with significant increment (p < 0.05) in renal enzymatic and non-enzymatic antioxidants.

Conclusion

SR leaf extract ameliorates GM induced nephrotoxicity and renal dysfunction and thus validates its ethnomedicinal use.     

Anti-inflammatory effects of Pulvis Fellis Suis extract in mice with ulcerative colitis

Ethnopharmacological relevance

Pulvis Fellis Suis is used in folk medicines to treat intestinal diseases, acute pharyngitis, whooping cough and asthma in China. Although several reports indicate that Pulvis Fellis Suis display diverse biological activities, such as antibacterial, anti-inflammatory and anti-infusorian effects, its effects on ulcerative colitis have not been previously explored.

Aim of the study

The purpose of the present study is to assess the anti-inflammatory effect of Pulvis Fellis Suis (PFS) extract in acute ulcerative colitis model induced by trinitrobenzene sulfonic acid (TNBS) in mice.

Materials and methods

Different doses of Pulvis Fellis Suis extract (100, 200 and 400 mg/kg/day) and sulfasalazine (500 mg/kg/day) were administered by gavage for 7 days after the induction of colitis with TNBS. The efficacy of PFS was studied by macroscopical and histological scoring systems as well as myeloperoxidase (MPO) activity. Serum levels, including tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were assayed by enzyme-linked immunoassay. The expression of cyclooxygenase (COX)-2 in the colons was assessed by immunohistochemical analysis.

Results

Treatment with PFS significantly attenuated macroscopic damage as compared with TNBS (P < 0.01). Histological analysis showed that PFS improved the microscopic structure and preserved some areas of the colonic mucosa structure. In addition, administration of PFS effectively inhibited COX-2 protein expression and MPO activity accumulation. TNF-α and IL-6 levels were also diminished dose-dependently (P < 0.05, P < 0.01), and IL-6 level obtained had no significant results by small dose of PFS. All the effects of these parameters were comparable to that of the standard sulfasalazine, especially at the highest dose level.

Conclusions

We have shown for the first time that PFS has an anti-inflammatory effect in TNBS-induced ulcerative colitis which might be related to the reduction of up-regulated TNF-α and IL-6 production, and that it may have therapeutic value in the setting of inflammatory bowel disease (IBD).     

The analgesic and anti-inflammatory effect of WIN-34B, a new herbal formula for osteoarthritis composed of Lonicera japonica Thunb and Anemarrhena asphodeloides BUNGE in vivo

Ethnopharmacological relevance

: Lonicera japonica Thunb and Anemarrhena asphodeloides BUNGE have been used for the treatment of a variety of inflammatory diseases, cold and infective diseases in many countries, including Korea and China.

Aim of the study

: This study aimed to assess the anti-nociceptive and anti-inflammatory activities of n-butanol fraction (WIN-34B) prepared from dried flowers of Lonicera japonica and dried roots of Anemarrhena asphodeloides as potential novel treatment of osteoarthritis.

Materials and methods

: Anti-nociceptive activities of WIN-34B (100, 200 and 400 mg/kg, p.o.) were measured using acetic acid-induced writhing response, formalin-induced paw licking, hot plate, radiant heat tail-flick, carrageenan-induced paw pressure, and Hargreaves tests, respectively. Anti-inflammatory activities of WIN-34B (100, 200 and 400 mg/kg, p.o.) were assessed using acetic acid-induced vascular permeability, carrageenan-induced paw edema, and croton oil-induced ear edema. Anti-osteoarthritis effect of WIN-34B was analyzed using monosodium iodoacetate (MIA)-induced osteoarthritis animal model.

Results

: WIN-34B exhibited better anti-inflammatory activity than that of celecoxib in carrageenan at the dose of 200 mg/kg and croton oil-induced paw edema and ear edema at the doses of 200 and 400 mg/kg. WIN-34B exhibited significant anti-inflammatory effects on vascular permeability. WIN-34B also exhibited significant anti-nociceptive activities in the late phase of formalin-induced paw licking and writhing response model in mice. In radiant heat tail-flick and carrageenan-induced paw pressure tests, WIN-34B at the dose of 400 mg/kg and at the doses of 200 and 400 mg/kg presented similar activities to indomethacin and celecoxib. Compared to indomethacin WIN-34B at 400 mg/kg showed similar or better anti-nociceptive activities after 1 and 2 h of theraphy in the hot plate test and better anti-nociceptive activity than that of celecoxib in Hargreves test. In the MIA-induced osteoarthritis animal models, WIN-34B at 400 mg/kg exhibited similar or better anti-nociceptive property than that of celecoxib throughout the pain measurement periods.

Conclusion

: When compared to celecoxib, WIN-34B exhibited similar or better anti-nociceptive and anti-inflammatory activities in osteoarthritic animal models, which may become a potential novel treatment for osteoarthritis.     

Olive (Olea europaea L.) leaf extract attenuates early diabetic neuropathic pain through prevention of high glucose-induced apoptosis: in vitro and in vivo studies

Aim of study

Since the leaves of olive have been recommended in the literature as a remedy for the treatment of diabetes and they also contain antioxidant agents, we decided to investigate the possible effects of olive leaf extract (OLE) on in vitro and in vivo models of diabetic pain neuropathy.

Materials and methods

The high glucose-induced cell damage in naive and NGF-treated Pheochromocytoma (PC12) cells and streptozotocin-induced diabetic rats were used. Tail-flick test was used to access nociceptive threshold. Cell viability was determined by MTT assay. Biochemical markers of neural apoptosis were evaluated using immunoblotting.

Results

We found that elevation of glucose (4 times of normal) sequentially increases functional cell damage and caspase-3 activation in NGF-treated PC12 cells. Incubation of cells with OLE (200, 400 and 600 μg/ml) decreased cell damage. Furthermore, the diabetic rats developed neuropathic pain which was evident from decreased tail-flick latency (thermal hyperalgesia). Activated caspase 3 and Bax/Bcl2 ratio were significantly increased in spinal cord of diabetic animals. OLE treatment (300 and 500 mg/kg per day) ameliorated hyperalgesia, inhibited caspase 3 activation and decreased Bax/Bcl2 ratio. Furthermore, OLE exhibited potent DPPH free radical scavenging capacity.

Conclusion

The results suggest that olive leaf extract inhibits high glucose-induced neural damage and suppresses diabetes-induced thermal hyperalgesia. The mechanisms of these effects may be due, at least in part, to reduce neuronal apoptosis and suggest therapeutic potential of olive leaf extract in attenuation of diabetic neuropathic pain.     

Antidepressant effect of Valeriana wallichii patchouli alcohol chemotype in mice: Behavioural and biochemical evidence

Ethnopharmacological relevance

Valeriana wallichii DC, an ayurvedic traditional medicine has now been shown to exist chemically as three distinct chemotypes. The study aimed to investigate the antidepressant effect of dichloromethane extract of Valeriana wallichii patchouli alcohol chemotype.

Materials and methods

Antidepressant effect of dichloromethane extract of Valeriana wallichii (10, 20 and 40 mg/kg, p.o.) using forced swim test, was determined in both acute and chronic study. The neurotransmitter levels were estimated in mouse forebrain after two weeks of dosing.

Results

Single administration of extract (40 mg/kg) significantly inhibited the immobility period in mice (p < 0.05). Similarly, chronic administration of extract (20 and 40 mg/kg) significantly reduced the immobility period and significantly increased the levels of norepinephrine and dopamine in mouse forebrain (p < 0.05).

Conclusions

The extract demonstrated antidepressant effect and significantly increased the norepinephrine and dopamine levels in forebrain.     

Acute, subacute toxicity and mutagenic effects of anacardic acids from cashew (Anacardium occidentale Linn.) in mice

Aim of the study

Anacardium occidentale Linn. (cashew) is a Brazilian plant that is usually consumed in natura and is used in folk medicine. Anacardic acids (AAs) in the cashew nut shell liquid are biologically active as gastroprotectors, inhibitors of the activity of various deleterious enzymes, antitumor agents and antioxidants. Yet, there are no reports of toxicity testing to guarantee their use in vivo models.

Materials and methods

We evaluated AAs biosafety by measuring the acute, subacute and mutagenic effects of AAs administration in BALB/c mice. In acute tests, BALB/c mice received a single oral dose of 2000 mg/kg, whereas animals in subacute tests received 300, 600 and 1000 mg/kg for 30 days. Hematological, biochemical and histological analyses were performed in all animals. Mutagenicity was measured with the acute micronucleus test 24 h after oral administration of 250 mg/kg AAs.

Results

Our results showed that the AAs acute minimum lethal dose in BALB/c mice is higher than 2000 mg/kg since this concentration did not produce any symptoms. In subacute tests, females which received the highest doses (600 or 1000 mg/kg) were more susceptible, which was seen by slightly decreased hematocrit and hemoglobin levels coupled with a moderate increase in urea. Anacardic acids did not produce any mutagenic effects.

Conclusions

The data indicate that doses less than 300 mg/kg did not produce biochemical and hematological alterations in BALB/c mice. Additional studies must be conducted to investigate the pharmacological potential of this natural substance in order to ensure their safe use in vivo.     

Effects of Scutellariae radix and Aloe vera gel extracts on immunoglobulin E and cytokine levels in atopic dermatitis NC/Nga mice

Aim of the study

The present study aimed to investigate the effects of Scutellariae radix (SR) and Aloe vera gel (AV), alone or in combination, on levels of immunoglobulin E (IgE) and inflammatory cytokines in spontaneous atopic dermatitis(AD)-like skin lesions.

Materials and methods

After spontaneous AD-like skin lesion was developed by adaptation to conventional conditions, mice were randomly assigned to control, SR (50 mg/kg, p.o.), AV (0.8 mg/kg, p.o.) and SRAV (50 mg of SR and 0.8 mg of AV/kg, p.o.) groups, and were treated for 6 weeks.

Results

SR and SRAV suppressed IL-5 levels compared with control, but had no effects on IgE levels (P < 0.05). AV increased IgE levels, but decreased both IL-5 and IL-10 compared with control (P < 0.05).

Conclusion

These results suggest that SR and AV modulate immunological responses in AD, mainly through influencing IL-5 or IL-10 levels.     

Barakol-induced apoptosis in P19 cells through generation of reactive oxygen species and activation of caspase-9

Ethnopharmacological relevance

Barakol, an anxiolytic agent isolated from Senna siamea leaves which has been traditionally used for producing natural sleep, has been described as toxic to patients.

Aim of the study

The aim of current study was to investigate the molecular mechanism of barakol-induced toxicity in mouse embryonal carcinoma P19 cell model.

Materials and methods

XTT assay was used to determine cell viability in P19 cells treated with barakol. Apoptotic cells were detected by Hoechst 33342 staining. Intracellular reactive oxygen species (ROS) generation was analyzed by flow cytometry using a fluorescent dye, DCFH-DA. Detection of apoptotic protein expression in P19 cells was performed by Western blot analysis. Caspase-9 activity was measured using a fluorescent immunosorbent enzyme assay kit.

Results

Treatment with barakol decreased cell viability in a concentration- and time-dependent manner with an IC₅₀ value of 1.5 mM in 24-h treated cells. A Hoechst 33342 assay revealed that barakol cytotoxicity was due to a significant increase in the number of apoptotic cells. Different scavengers to characterize ROS were utilized and revealed that hydroxyl radicals played a major role in ROS-induced apoptosis in barakol-treated cells. Western blot analysis demonstrated that barakol-induced apoptosis was mediated by the increase in expression ratio of Bax/Bcl-2. Furthermore, increase in caspase-9 activity after exposure to barakol for 24 h was also observed. Pretreatment of cells with N-acetyl-l-cysteine (NAC) attenuated intracellular ROS generation, the Bax/Bcl-2 protein expression, and apoptosis.

Conclusions

The mechanism of barakol-mediated toxicity in P19 cells is mainly associated with the ROS generation, followed by the imbalance of the Bax/Bcl-2 ratio, and caspase-9 activation leading to apoptotic cell death. Pretreatment of cells with NAC could antagonize the toxicity produced by barakol.     

5α-reductase inhibition and hair growth promotion of some Thai plants traditionally used for hair treatment

Ethnopharmacological relevance

Many Thai traditional herbs have been used for hundreds of years for hair treatment and nourishment, including hair loss. However, scientific evidence about their mechanisms of action has not yet been elucidated.

Aims of the study

The purpose of this research is to define the possible mechanisms involved in hair loss treatment of the selected plants by determining the 5α-reductase enzyme inhibition and hair growth promoting activities, and the relationship between these two activities.

Materials and methods

Seventeen Thai plants traditionally used for hair treatment were selected. The plants were dried, ground and extracted by maceration with ethyl alcohol. These extracts were further tested for 5α-reductase inhibition using enzymes from rat livers. Hair growth promoting activity was tested in C57BL/6 mice.

Results

Carthamus tinctorius L. was the most potent 5α-reductase inhibitor, with a finasteride equivalent 5α-reductase inhibitory activity (FEA) value of 24.30 ± 1.64 mg finasteride equivalent per 1 g crude extract. Phyllanthus emblica L. was the second most potent inhibitor, with FEA of 18.99 ± 0.40. Rhinacanthus nasutus (L.) Kurz. was the least potent 5α-reductase inhibitor (FEA 10.69 ± 0.96). Carthamus tinctorius also was the most potent hair growth promoter in C57BL/6 mice. There were strong relationships between 5α-reductase inhibitory activity and hair growth promoting activity (r = 0.719), and between 5α-reductase inhibitory activity and hair follicle count (r = 0.766).

Conclusions

Ethanolic extract of Carthamus tinctorius was the most potent 5α-reductase inhibitor and hair growth promoter. This discovery may lead to the development of new alternative medicines for hair loss prevention and treatment.     

Evaluation of the use of Cocos nucifera as antimalarial remedy in Malaysian folk medicine

Ethnopharmacological relevance

White flesh extract of Cocos nucifera (coconut) was studied to ascertain the ethnopharmacological standing of its antimalarial usage in Malaysian folk medicine.

Materials and methods

The crude methanol extract was investigated for phytochemical constituents and acute oral toxicity. Antimalarial activity of different extract doses of 50, 100, 200 and 400 mg/kg were investigated in vivo against Plasmodium berghei (NK65) infections in mice during early, established and residual infections. Chloroquine (20 mg/kg) and pyrimethamine (1.2 mg/kg) were used as reference drugs.

Results

The results revealed that the extract contained some phytochemical constituents and is toxicologically safe by oral administration. The extract significantly reduced the parasitaemia by the 200 and 400 mg/kg doses in the all three in vivo assessment assays. However, the extract did not significantly increase the survival time of the infected mice.

Conclusions

The observed pharmacological activities suggest that the Malaysian folkloric medicinal application of Cocos nucifera has a pharmacological basis.     

Nepeta cataria L. var. citriodora (Becker) increases penile erection in rats

Ethnopharmacological relevance

Nepeta cataria (NC), catnip, induces pleasure in cats and humans.

Aim of the study

Because sexual behavior is involved in pleasure, the effect of NC on sexual behavior and penile erection was evaluated in male rats that were acutely fed chow enriched with 10% NC leaves. Further, yawning was monitored because we previously demonstrated that NC modifies dopaminergic-related behaviors and that sexual behavior is closely linked with the dopaminergic system. The general activity and the motor coordination were examined to investigate the possible motor and emotional interferences of the sexual performance.

Material and methods

Male rats of the NC group received for a 4 h period the chow enriched with 10% NC leaves while the control groups received regular chow. Fifteen min after the end of the 4 h period of NC feeding the sexual behavior, apomorphine-induced penile erection and motor coordination were observed; the general activity in the open field was assessed 0, 15, 30 and 60 min after treatment.

Results

NC treatment increased male rat's penile erection. A slightly facilitation on male rat sexual behavior and a decreased in general activity of NC treated rats were observed. No effects on motor coordination and yawning episodes were detected by the NC treatment.

Conclusions

It was suggested that NC increases penile erection and slightly improves male rat sexual behavior by an action on dopaminergic systems.     

Analgesic effects and anti-inflammatory properties of the crude methanolic extract of Schwenckia americana Linn (Solanaceae)

Aim of the study

To evaluate analgesic effect and anti-inflammatory properties of Schwenckia americana (Solanaceae), a medicinal plant used for treating rheumatic pains and swelling in North-western Nigeria.

Materials and methods

Three doses (25 mg/kg, 50 mg/kg and 100 mg/kg) of the crude methanolic extract of Schwenkia americana were evaluated for analgesic and anti-inflammatory activities using acetic acid induced writhing test, formalin induced nociception, and formalin induced hind paw oedema in rats.

Results

All doses (25, 50, 100 mg/kg) of the extract tested were effective. The extract at the tested doses produced a percentage inhibition of the acetic acid induced abdominal constriction of (53.3, 58.0 and 86.7%), respectively. A percentage inhibition of the formalin induced nociception of 44.00, 56.04, and 56.04% (early phase) and 33.00, 36.63 and 59.71% (late phase) was also produced. The inhibition of oedema formation increased with increasing dosage from 25 to 100 mg/kg. The crude extract produced a statistically significant analgesic and anti-inflammatory activity comparable to the effect of standard drug (10 mg/kg Piroxicam).

Conclusion

This study demonstrated the potential analgesic and anti-inflammatory properties of crude methanolic extract of Schwenkia americana thus justifying its traditional usage.     

Gastroprotective and safety effects of WIN-34B, a novel treatment for osteoarthritis, compared to NSAIDs

Ethnopharmacological relevance

The dried flowers of Lonicera japonica, also known as Japanese honeysuckle, and the dried root of Anemarrhena asphodeloides, the component herbs of WIN-34B, are traditionally used in Eastern medicine to treat various inflammatory conditions including arthritis.

Objective

To study the acute and chronic toxicities of WIN-34B and to compare its effects on gastric mucosa with those of diclofenac, a widely used NSAID, and celecoxib, a selective COX-2 inhibitor.

Materials and methods

To investigate acute toxicity, we orally administered a single dose of 5000 mg/kg WIN-34B to rats. To investigate chronic toxicity, we orally administered 500, 1000 or 2000 mg/kg WIN-34B to rats daily for 13 weeks. To assess its effects on gastric mucosa, rats received either a single dose or repeated doses of WIN-34B (400, 1000, or 2000 mg/kg), diclofenac (10, 40, or 80 mg/kg), celecoxib (100 or 1000 mg/kg), or vehicle, after which samples of gastric mucosa were assessed grossly and histologically. We also measured tissue activity of myeloperoxidase and synthesis of eicosanoids, including prostaglandin E₂ (PGE₂) and leukotriene B₄ (LTB₄). To further assess its effects, we administered WIN-34B to rats either intraperitoneally or orally, measured gastric injury scores using a rat model of diclofenac-induced gastric injury, and measured eicosanoid synthesis.

Results

WIN-34B showed no signs of acute or chronic toxicity in terms of general behavior, gross appearance of the internal organs, blood chemistry, or mortality. WIN-34B did not cause significant gastric mucosal damage after single or repeated doses. In contrast, diclofenac and celecoxib both caused gastric damage. In terms of eicosanoid synthesis, WIN-34B significantly suppressed LTB₄ synthesis while both diclofenac and celecoxib increased LTB₄ synthesis. WIN-34B slightly reduced PGE₂ production, while both diclofenac and celecoxib significantly reduced PGE₂ production. In a rat model of diclofenac-induced gastric injury, WIN-34B significantly suppressed LTB₄ synthesis and restored PGE₂ release.

Conclusions

These results demonstrate that WIN-34B did not cause acute or chronic toxicity in male or female rats. In addition, WIN-34B did not cause significant gastric mucosal damage, instead appearing to protect the mucosa from diclofenac-induced gastric damage through the regulation of PGE₂ and LTB₄.     

Cytochrome P450 inhibitory potential of Triphala--a Rasayana from Ayurveda

Ethnopharmacological relevance

‘Triphala’ is one of the age-old, most commonly used polyherbal preparation from Ayurveda as Rasayana drug.

Aim of the study

This study was aimed at evaluating the effect of ‘Triphala’ on drug modulating enzymes to assess its safety through its potential to interact with co-administered drugs.

Materials and methods

The cytochrome P450 inhibitory effect of ‘triphala’ formulation was investigated on rat liver microsomes using CYP450-CO complex assay and on individual isoform such as CYP3A4 and 2D6 using fluorescence screening. RP-HPLC method was developed to standardize ‘triphala’ and its individual components using gallic acid as analytical marker compound.

Results

RP-HPLC analysis demonstrated the presence of gallic acid (4.30 ± 2.09 mg/g) in the formulation. The formulation showed 23% inhibition of the rat liver microsomes through CYP450-CO complex assay which is comparatively less when compared with the individual components. Further, the effect of standardized formulation dissolved in ethanol showed CYP3A4 and CYP2D6 inhibitory activity at the IC₅₀ values of 119.65 ± 1.91 μg/ml and 105.03 ± 0.98 μg/ml respectively. Gallic acid was also found to inhibit both the isoforms at the IC₅₀ values of 87.24 ± 1.11 μg/ml and 92.03 ± 0.38 μg/ml respectively.

Conclusions

Various concentrations of the formulation and its individual components showed significantly less inhibitory activity (p < 0.001) on individual isoforms when compared with the positive control. Assessment on the in vitro effect of ‘triphala’ on drug modulating enzymes has important implications for predicting the likelihood of herb-drug interactions if these are administered concomitantly.     

Anti-inflammatory, antioxidant, anti-tyrosinase and phenolic contents of four Podocarpus species used in traditional medicine in South Africa

Ethnopharmacological relevance

Species of Podocarpus are used traditionally in their native areas for the treatment of fevers, asthma, coughs, cholera, chest complaints, arthritis, rheumatism, venereal diseases and distemper in dogs.

Aims of the study

To investigate the antioxidant, anti-inflammatory and anti-tyrosinase activities of four Podocarpus species, Podocarpus elongatus, Podocarpus falcatus, Podocarpus henkelii and Podocarpus latifolius, used in traditional medicine in South Africa. Phytochemical analysis to determine the phenolic contents was also carried out.

Materials and methods

DPPH, FRAP and β-carotene-linoleic acid assays were used to determine the antioxidant/radical scavenging activities of these species. Anti-inflammatory activity of these species was assayed against two cyclooxygenase enzymes (COX-1 and COX-2). Tyrosinase inhibition activity was analysed using the modified dopachrome method with l-DOPA as the substrate. Phenolics were quantitatively determined using spectrophotometric methods.

Results

Stems of Podocarpus latifolius exhibited the lowest EC₅₀ (0.84 μg/ml) inhibition against DPPH. The percentage antioxidant activity based on the bleaching rate of β-carotene ranged from 96% to 99%. High ferric reducing power was observed in all the extracts. For COX-1, the lowest EC₅₀ value was exhibited by stem extracts of Podocarpus elongatus (5.02 μg/ml) and leaf extract of Podocarpus latifolius showed the lowest EC₅₀ against COX-2 (5.13 μg/ml). All extracts inhibited tyrosinase activity in a dose-dependent manner with stem extract of Podocarpus elongatus being the most potent with an EC₅₀ value of 0.14 mg/ml. The total phenolic content ranged from 2.38 to 6.94 mg of GAE/g dry sample.

Conclusion

The significant pharmacological activities observed support the use of these species in traditional medicine and may also be candidates in the search for modern pharmaceuticals in medicine, food and cosmetic industries.