Antibacterial Activities of Methanolic Seeds Extract of Black pepper (Piper nigrum L.) against Gram Positive Staphylococcus aureus & Gram-Negative Escherichia coli.

Evaluation of the in vitro antibacterial activity of Methanolic extracts isolated from Black pepper seeds (Piper nigrum L.) against two infection causing pathogens, Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. Between July 2022 and June 2023, this experimental study was conducted at the Mymensingh Medical College's Department of Pharmacology and Therapeutics in conjunction with the Department of Microbiology. Using the disc diffusion and broth dilution methods, the antibacterial activity of methanolic extract of black pepper seeds (MBPE) was evaluated at various doses. The solvents Methanol and 10.0% Di Methyl Sulfoxide (DMSO) were used to make the extract. Using the broth dilution procedure, the conventional antibiotic Ciprofloxacin was utilized and the outcome was contrasted with that of Methanol extracts. Methanolic extract of black pepper seeds (MBPE) at seven distinct concentrations (100, 80, 60, 40, 20, 10 and 5 mg/ml) were utilized, then later in chosen concentrations as needed to confirm the extracts' more precise margin of antimicrobial sensitivity. At 80 mg/ml and above doses of the MBPE, it had an inhibitory impact against the aforementioned microorganisms. For Staphylococcus aureus and Escherichia coli the MIC were 60 and 75 mg/ml in MBPE respectively. As of the MIC of Ciprofloxacin was 1µg/ml against Staphylococcus aureus and Escherichia coli. In comparison to MICs of MBPE for the test organisms, the MIC of Ciprofloxacin was the lowest. This study clearly shows that Staphylococcus aureus and Escherichia coli are sensitive to the methanolic extract of black pepper seeds' antibacterial properties.

Bark extract of Chaetocarpus castanocarpus (Roxb.) exhibits potent sedative, anxiolytic, and antidepressant effects through an in vivo approach in Swiss albino mice.

OBJECTIVE: Standard phytochemical investigations were performed to identify the secondary metabolites in the methanol extract of Chaetocarpus castanocarpus bark (MECC) and investigate the neuropharmacological potential of MECC in Swiss albino mice. MATERIALS AND METHODS: Swiss albino mice were used in the forced swimming test (FST) and tail suspension test (TST) to evaluate the antidepressant effect of MECC. Also, the hole board test (HBT) and elevated plus maze (EPM) were conducted to examine anxiolytic activities. In contrast, the open field test (OFT) and hole cross test (HCT) were employed to evaluate sleeping disorders. RESULTS: Alkaloids, glycosides, flavonoids, terpenoids, coumarins, and tannins are only a few secondary metabolites identified in MECC by qualitative and quantitative phytochemical investigations. The oral administration of MECC considerably shortened the immobility duration during FST and TST. Encouraging dose-dependent anxiolytic effects were also observed in all relevant experiments compared to the control. Additionally, during the OFT and HCT assessment, a noteworthy decline in the locomotor activities of the experimental animals was observed. CONCLUSIONS: The results of this investigation suggest that the Chaetocarpus castanocarpus bark is a possible source of therapeutic candidates for treating neurological disorders.

Antibacterial Effect of Moringa (Moringa oleifera) Leaf Ethanolic Extract Against Staphylococcus aureus and Escherichia coli.

Increasing resistance of pathogenic microorganisms to synthetic antibiotics has lead to the search for alternative drug sources. In this regard, one of the reputed Medicinal plant, Moringa (Moringa oleifera) was investigated for potential antimicrobial effect against some commonly encountered bacteria such as Staphylococcus aureus, Escherichia coli. This experimental study was conducted from July 2019 to June 2020 in the Department of Pharmacology and Therapeutics in collaboration with the Department of Microbiology, Mymensingh Medical College, Bangladesh to determine the antibacterial effect of Ethanolic extract of Moringa oleifera leaf (EMLE) against aforementioned bacteria. The antibacterial activity was tested at different concentrations (100, 200, 400, 600, 800 and 1000µg/ml) of Ethanolic extract by using disc diffusion and broth dilution method. Dose dependent inhibitory effect was seen against the test organisms using disc diffusion method. The maximum zone of inhibition was 19 mm against S. aureus and 20mm against E. coli at 100.0% (1000µg/ml) concentration. The minimum inhibitory concentrations (MICs) of EMLE were 400µg/ml and 500µg/ml against Staphylococcus aureus and Escherichia coli respectively. The present study showed that Ethanolic extract of Moringa leaf demonstrated antibacterial effects against food borne pathogens. Further studies are required to detect and isolate the active ingredients present in the Moringa leaves extract responsible for its antibacterial effect.

A Systematic Review and Meta-analysis Investigating the Pain-Relieving Effect of Interferential Current on Musculoskeletal Pain.

BACKGROUND: Interferential current is one of the most common electrotherapeutic modalities used in the treatment of painful conditions. Patients seeking medical help to reduce their musculoskeletal pain can be treated using interferential current. OBJECTIVE: The current review aimed to analyze the recently available information regarding the efficacy of interferential current in alleviating the pain of musculoskeletal origin. METHODS: This study used Scopus, CINAHL, Cochrane Library, Web of Science, MEDLINE, Embase, and EBSCOas as data sources. The initial selection of the studies, thorough assessment of the full articles, and extraction of the necessary study characteristics were carried out by two independent reviewers. Another two independent reviewers assessed the methodological quality of each included trial against 39 criteria. These criteria were integrated from several popular scales. Pain intensity-measured using the visual analog scale, numeric pain rating scale, or McGill Pain Questionnaire-was the outcome of interest. RESULTS: This review included 35 trials of variable methodological quality from which 19 trials were selected for the meta-analysis. In general, interferential current alone versus placebo demonstrated a significant pain-relieving effect. On the other hand, interferential current showed no significant difference when added to standard treatment compared with placebo plus standard treatment or standard treatment alone. Similarly, interferential current showed no significant difference when compared with other single interventions (laser, transcutaneous electrical nerve stimulation, cryotherapy). CONCLUSIONS: Interferential current alone is better than placebo at discharge. However, the low number of studies raises suspicions about this conclusion. Interferential current alone or added to other interventions is not more effective than comparative treatments in relieving musculoskeletal pain.

Production of high quality biodiesel from novel non-edible Raphnus raphanistrum L. seed oil using copper modified montmorillonite clay catalyst.

This study focused on producing high quality and yield of biodiesel from novel non-edible seed oil of abundantly available wild Raphnus raphanistrum L. using an efficient, recyclable and eco-friendly copper modified montmorillonite (MMT) clay catalyst. The maximum biodiesel yield of 83% was obtained by base catalyzed transesterification process under optimum operating conditions of methanol to oil ratio of 15:1, reaction temperature of 150 °C, reaction time of 5 h and catalyst loading of 3.5%. The synthesized catalyst and biodiesel were characterized for their structural features and chemical compositions using various state-of-the-art techniques, including x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, Fourier transform infrared spectroscopy, nuclear magnetic resonance (1H, 13C) and gas chromatography-mass spectroscopy. The fuel properties of the biodiesel were estimated including kinematic viscosity (4.36 cSt), density (0.8312 kg/L), flash point (72 °C), acid value (0.172 mgKOH/g) and sulphur content (0.0002 wt.%). These properties were compared and found in good agreement with the International Biodiesel Standards of American (ASTM-951, 6751), European Committee (EN-14214) and China GB/T 20828 (2007). The catalyst was re-used in five consecutive transesterification reactions without losing much catalytic efficiency. Overall, non-edible Raphnus raphanistrum L.. seed oil and Cu doped MMT clay catalyst appeared to be highly active, stable, and cheap contenders for future biofuel industry. However, detailed life cycle assessment (LCA) studies of Raphnus raphanistrum L. seed oil biodiesel are highly recommended to assess the technical, ecological, social and economic challenges.

In Vitro Antibacterial Activity of Ethanol Extracts of Cinnamomum zeylanicum against Pseudomonas aeruginosa.

Cinnamomum zeylanicum as medicinal plants are measured as new resources for preparing elements in the treatment of antibiotic-resistant microbes as alternatives to antibiotics. This study was aimed to evaluate the antibacterial activity of ethanol extracts of Cinnamomum zeylanicum against a Gram-negative bacteria Pseudomonas aeruginosa. This experimental study was carried out in the department of Pharmacology & Therapeutics and department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh from July 2017 to July 2018. Evaluation of the in vitro antibacterial activity of ethanol extracts of Cinnamomum zeylanicum against Pseudomonas aeruginosa was performed by disc diffusion method. And also in this study we used broth dilution method to determine the minimum inhibitory concentration (MIC). Ethanol cinnamon extract (ECE) was found active against P. aeruginosa. Zone of inhibition (ZOI) ranged between 6-25mm at different concentration of extracts. The MIC was 0.3g/ml. Cinnamomum zeylanicum showed strong antibacterial activity against a Gram-negative bacteria Pseudomonas aeruginosa. The results may contribute to the development of potential antimicrobial agents for inclusion in antipseudomonal regimens.

Morphological Changes of Length of Prostate in Different Age Groups of Bangladeshi Cadaver.

Benign prostatic hyperplasia is the most common prostatic problem for men older than age 50. It is a condition in men in which the prostate is enlarged but it is not cancerous. The prostate goes through 2 (two) main growth periods as a person ages. The first happens early in pubescence, when the prostate doubles in size. The second stage of growth begins around age twenty five and continues throughout most of a man's life. Benign prostatic hyperplasia often occurs with second growth phase. In the treatment of prostatic disorders, estimation of the length of prostate has been used to select the surgical approach. Transurethral resection of prostate (TURP) is preferred for small glands and open prostatectomy for larger ones. As the prostate gland is dependent on androgen for its growth, the prostatic length reflects the hormonal status of the subjects. This cross sectional descriptive study was conducted in Department of Anatomy, Mymensingh Medical College, Mymensingh, Bangladesh from April 2015 to September 2015 to find out the difference in length of the prostate of Bangladeshi people in relation to age. The present study was performed on 67 postmortem human prostate glands collected from the morgue in the Department of Forensic Medicine, Mymensingh Medical College, by non random purposive sampling technique. The specimens were collected from Bangladeshi dead body, age starting from 10-80 years. All the specimens were classified into 3(three) classes - Group A (upto 18 years), Group B (19-45 years) and Group C (>45 years) according to age. Dissection was performed according to standard autopsy techniques. The length of the prostate was measured and recorded. The mean±SD length of the prostate was 1.76±0.60cm, 2.65±0.56cm and 2.88±0.70cm in Group A, B and C respectively. The maximum mean length of the prostate was in Group C (2.88cm) and minimum was in Group A (1.76cm). It was observed that the length of the prostate was increased with age. Variance analysis shows that mean differences of length of the prostate were highly significant among all age groups. The length of prostate gland was found to be increase with age. For statistical analysis, variations between age groups were analyzed by students unpaired 't' test. The present study will help to increase the information pool on the length of prostate gland of Bangladeshi people.

The Antibacterial Activity of Ethanolic Extract of Cinnamon (Cinnamomum zeylanicum) against two Food Borne Pathogens: Staphylococcus aureus And Escherichia coli.

Evaluation of the in vitro antibacterial activity of the ethanolic extract isolated from Cinnamomum zeylanicum bark against two food borne pathogens, Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. This experimental study was carried out in the department of Pharmacology & Therapeutics in collaboration with the department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh from July 2017 to July 2018. The antibacterial activity was tested at different concentrations of extracts of spice by using disc diffusion method. The extracts were prepared by using a solvent ethanol. The test microorganisms were also tested for their activity against a standard antibiotic Amikacin (500mg) by disc diffusion method and the result was compared with that of ethanolic extracts. Cinnamon had inhibitory activity against both Staphylococcus aureus and Escherichia coli. The ethanolic extracts were more effective against Staphylococcus aureus than E. coli. Staphylococcus aureus showed activity from 60% conc. (zone of inhibition 17mm) where E. coli from 80% conc. (ZOI 18mm). Maximum zone of inhibition was 26mm for both the test organisms. This result was also compared to those obtained against a standard antibiotic Amikacin where extract produced wider zone of inhibition of 26mm as compared to Amikacin for both test organisms. The present study showed that ethanolic extract of cinnamon demonstrated stronger antimicrobial effect against food borne pathogens.

Amelioration of Benzo[a]pyrene-induced oxidative stress and pulmonary toxicity by Naringenin in Wistar rats: A plausible role of COX-2 and NF-κB.

Naringenin is a naturally occurring flavanones and has been found to exhibit free radical scavenging, enzyme inhibition, antioxidants, anti-inflammatory, and anticancer activities. Present study was designed to evaluate the protective role of naringenin against benzo[a]pyrene (B[a]P)-induced oxidative stress and pulmonary toxicity. Rats were treated with naringenin at a dose of 100 mg/kg body weight (b. wt.), by oral gavage. B[a]P in a single dose of 50 mg/kg b. wt. was given intraperitoneally. Total protein, total cell counts, lactate dehydrogenase, lipid peroxidation, reduced glutathione, antioxidant enzymes activities, lung histology and expression of nuclear factor kappa B (NF-κB), and cyclo-oxygenase-2 (COX-2) was assessed to evaluate protective effects of naringenin. Histopathological and immunohistochemical studies were also carried out to observe lung toxicity and inflammation. B[a]P administration enhanced the levels of lung injury markers and reduced antioxidant enzymes activities. Naringenin treatment attenuated the levels of oxidative stress by restoring antioxidant enzymes, further improved lung histological damage and significant decrease in inflammatory responses. Naringenin also effectively decreased the expression of NF-κB, and COX-2 induced by B[a]P. These findings suggest that naringenin supplementation is beneficial in maintaining the integrity of alveoli and the epithelium that may be used as a protective agent in B[a]P-induced oxidative stress and lung damage. However, further studies are warranted to elucidate the potential mechanism of action of naringenin.

Study of Prostatic Volume and its Variations in Different Age Groups of Bangladeshi Cadaver.

Benign prostatic hyperplasia and carcinoma of the prostate are the most common disorders of Bangladeshi male in recent years. Volume of the prostate is necessary to estimate the amount of BPH adenoma to determine the appropriate therapy or to select the surgical approach. Transurethral resection of prostate (TURP) is preferred for small glands and open prostatectomy for larger ones. Decrease in prostatic mass after hormonal manipulation or radiation therapy can be used as an indicator of therapeutic efficacy. The effect of prostate volume on biopsy outcome was assessed and was noted that there was an inverse relationship in between size of the gland and prostate cancer. A cross sectional descriptive study was conducted in Department of Anatomy, Mymensingh Medical College, Mymensingh, Bangladesh to find out the difference in volume of the prostate gland of Bangladeshi people in relation to age. The present study was performed on 67 postmortem human prostate gland collected from the morgue in the Department of Forensic Medicine, Mymensingh Medical College by non random purposive sampling technique. The specimens were collected from Bangladeshi cadaver of age ranging from 10 to 80 years. All the specimens were grouped into three categories: Group A (upto 18 years), Group B (19 to 45 years) and Group C (above 45 years) according to age. Dissection was performed according to standard autopsy techniques. The volume of the prostate gland were measured and recorded. The mean volume of the prostate gland was 13.75ml in Group A, 24.44ml in Group B and 29.72ml in Group C. Variance analysis shows that mean differences of volume of the prostate were highly significant among all age groups. The volume of prostate gland was found to be increased with increasing age. For statistical analysis, differences between age groups were analyzed by using students unpaired 't' test. The present study will help to increase the information pool on the volume of prostate gland of Bangladeshi people.

Antibacterial Effect of Curcuma longa (Turmeric) Against Staphylococcus aureus and Escherichia coli.

This observational study was conducted during the period from July 2010 to June 2011 in the Department of Pharmacology in the collaboration of Department of Microbiology, Mymensingh Medical College, Mymensingh to determine the profile of antibacterial effect of Crude Turmeric paste aqueous turmeric extract, and standard antibiotic Amikacin against Staphylococcus aureus and Escherichia coli. Three separate experiments were done e.g. (Expt- I) Inhibitory effect of Crude Turmeric paste incorporated into nutrient agar (NA) media, (Expt- II) Minimum inhibitory concentration of (a) Aqueous Turmeric extract and (b) Amikacin by broth dilution technique and (Expt-III) their subculture study in nutrient agar (NA) media for confirmation of respective results of previous experiments. Inhibitory effects were observed against the growth of Staph Aureus and Esch coli at 10% and 30% respectively of Crude Turmeric paste incorporated into NA media. The broth dilution technique was followed to determine the MIC of Aqueous Turmeric extract and Amikacin. The MIC of Aqueous Turmeric extract was 800 µg/ml against Staph aureus and that against Esch coli was 2000 µg/ml and the MIC of Amikacin was 10 µg/ml for both the bacteria. The MIC of Amikacin was the lowest in comparison to MIC of Aqueous Turmeric extract for complete inhibition of growth of Staph aureus and Esch coli. The subculture study showed similar results with that of previous experiments in terms of inhibitory effects of Crude Turmeric paste and MIC of Aqueous Turmeric extract and Amikacin against all of the organisms studied.

Comparative antioxidant activity study of some commonly used spices in Bangladesh.

Many spices have been shown to impart an antioxidative effect in foods. This study summarized the literature on the antioxidative effects of spices. The term spice is defined as dry plant material that is normally added to food to impart flavor. The methanolic crude extracts of Allium sativum, Coriandrum sativum, Cuminum cyminum, Zingiber officinale, Cinnamomum verum, Elettaria cardamomum and Cinnamomum tamala were screened for their free radical scavenging properties using ascorbic acid as standard antioxidant. Free radical scavenging activity was evaluated using 1,1-diphenyl-2-picryl hydrazyl (DPPH) free radical. The overall antioxidant activity of Cuminum cyminum was found to be the strongest, followed in descending order by Z. officinale, C. sativum, A. sativum, C. tamala, C. verum, E. cardamomum. The IC50 values of the extracts ranged between 15.48 and 217.431 (microg mL(-1)). The ascorbic acid levels was 22.78 (microg mL(-1)) the present study revealed that the selected plants would exert several beneficial effects by virtue of their antioxidant activity and could be harnessed as drug formulation.

Anti-oxidative effect of Rhodiola imbricata root extract in rats during cold, hypoxia and restraint (C-H-R) exposure and post-stress recovery.

Anti-oxidative potential of Rhodiola imbricata root aqueous extract was examined in rats, administered orally at a dose of 100 mg/kg both in single and multiple doses, 30 min prior to cold (5 degrees C)-hypoxia (428 mmHg)-restraint (C-H-R) exposure. Lipid per-oxidation, anti-oxidant parameters and lactate dehydrogenase (LDH), were studied in blood, liver and muscle of rats on attaining T(rec)23 degrees C during C-H-R exposure and after recovery (T(rec)37 degrees C) from C-H-R induced hypothermia. The results of untreated control rats on attaining T(rec)23 degrees C showed a significant increase in blood, liver and muscle malondialdehyde (MDA) and LDH levels. Hepatic catalase (CAT) and muscle glutathione S-transferase (GST) also increased significantly. Administration of single dose of Rhodiola imbricata root aqueous extract significantly restricted rise in blood MDA, increased blood reduced glutathione (GSH) and superoxide dismutase (SOD) activity with restricted rise in blood, liver and muscle LDH; improved liver and muscle SOD on attaining T(rec)23 degrees C and T(rec)37 degrees C; liver CAT on attaining T(rec)23 degrees C and liver GST during recovery. Multiple doses treatment of the extract further increased blood, liver and muscle GSH and GST levels; restricted increase in LDH on attaining T(rec)23 degrees C and recovery; increased CAT during recovery. Results suggested the anti-oxidant potential of Rhodiola root extract during C-H-R exposure and post-stress recovery and it also maintained cell membrane permeability.

Mechanism of action of Rhodiola imbricata Edgew during exposure to cold, hypoxia and restraint (C-H-R) stress induced hypothermia and post stress recovery in rats.

Mechanism of rhodiola root extract adaptogenic activity was studied in rats. The extract was orally administered in rats (100mg/kg body weight), 30 min prior to cold (5 degrees C)-hypoxia (428 mmHg)-restraint (C-H-R) exposure up to fall of T(rec)23 degrees C and recovery (T(rec)37 degrees C) from hypothermia. In untreated control rats serum lactate and non-esterified fatty acids (NEFA) increased on attaining T(rec)23 degrees C with decreased blood enzyme activities hexokinase (HK), phosphofructokinase (PFK), citrate synthase (CS) and glucose-6-phosphate dehydrogenase (G-6-PD), on attaining T(rec)23 degrees C and T(rec)37 degrees C. Decreases were also observed in liver and muscle tissues HK and G-6-PD enzyme activities and liver glycogen and CS on attaining T(rec)23 degrees C and recovery; muscle PFK during recovery; muscle CS on attaining T(rec)23 degrees C. Single and five doses of extract administration restricted increase in serum lactate values of rats on attaining T(rec)23 degrees C and maintained blood NEFA in single dose extract treated animals, indicating improved utilization of NEFA as energy fuel. The single and five doses extract treatment decreased or better maintained tissue glycogen and enzyme activities, viz. HK, PFK, CS and G-6-PD, in blood, liver and muscle, on attaining T(rec)23 degrees C and recovery. The results suggest that rhodiola extract treatment in rats shifted anaerobic metabolism to aerobic, during C-H-R exposure and post stress recovery.

Abrogation of DEN/Fe-NTA induced carcinogenic response, oxidative damage and subsequent cell proliferation response by Terminalia chebula in kidney of Wistar rats.

In an effort to identify a new chemopreventive agent, the present study was conducted to investigate the role of T. chebula in the prevention of ferric nitrilotriacetic acid (Fe- NTA) induced oxidative stress and renal tumorigenesis in Wistar rats. A single application of Fe-NTA (9 mg Fe/kg body weight, intraperitoneally) significantly induced oxidative stress and elevated the marker parameters of tumor promotion. However, the pretreatment of animals with different doses of T. chebula extract (25 and 50 mg/kg body weight) restored the levels of reduced glutathione (GSH) and cellular protective enzymes (p < 0.05). Concomitantly, malondialdehyde (MDA) formation and hydrogen peroxide content were also reduced significantly (p < 0.05) at both the doses. The promotion parameters tested (ornithine decarboxylase activity and DNA synthesis) were also significantly suppressed (p < 0.05). T. chebula also inhibited N-diethyl nitrosamine initiated renal carcinogenesis by showing reduction in the number of animals with renal cell tumors and percentage incidence of tumor as compared to the DEN initiated and Fe-NTA promoted rats. The study was further histologically confirmed. These results suggest a potential role of T. chebula in protection from Fe-NTA-induced renal carcinogenesis and oxidative damage.

Experiences with dose finding in patients in early drug development: the use of biomarkers in early decision making.

With the increasing cost and complexity of drug development, biomarkers will play an increasing role in the early phases. Biomarkers can be classified into target, mechanistic, or outcome with varying degrees of linkage to disease or treatment effect. They can be used to determine proof of concept by characterising the efficacy or safety profiles, or determining differentiation from any competitor drugs. PK/PD modelling of biomarker data for novel and marketed compounds can be used to predict outpatient dose response. Subsequent simulations may replace or reduce the size and cost of larger phase 2b outpatient studies. Two examples of biomarkers and PK/PD modelling used to characterise dose response are presented. Penile plethysmography (RigiScan Plus) in male erectile dysfunction and phenylephrine challenge urethral pressure in benign prostatic hyperplasia are used to reduce time and cost to reach major exploratory development decision points in these indications.

Butea monosperma and chemomodulation: protective role against thioacetamide-mediated hepatic alterations in Wistar rats.

The present study was carried out to study the effect of Butea monosperma, a known liver acting drug on the tumor promotion related events of carcinogenesis in rat liver. Thioacetamide (TAA) was used to induce tumor promotion response and oxidative stress and caused significant depletion in the detoxification and antioxidant enzyme armory with concomitant elevation in malondialdehyde (MDA) formation, hydrogen peroxide (H(2)O(2)) generation, ornithine decarboxylase (ODC) activity and unscheduled DNA synthesis. However, B. monosperma pretreatment at two different doses restored the levels of the above-said parameters (p < 0.001) in a dose-dependent manner. The alcoholic extract of B. monosperma used in the present study seems to offer dose-dependent protection and maintain the structural integrity of hepatic cells. This was evident from the significant reduction in TAA-induced serum GOT, GPT, Lactate dehydrogenase (LDH) and gamma-Glutamyl transpeptidase activity (GGT) activities (p < 0.001). These investigations validate the use of B. monosperma in liver disorders by Ayurvedic physicians. Overall results indicate that the methanolic extract of B. monosperma possesses hepatoprotective effects and also it might suppress the promotion stage via inhibition of oxidative stress and polyamine biosynthetic pathway.

Inhibition of two stage renal carcinogenesis, oxidative damage and hyperproliferative response by Nigella sativa.

In an earlier communication we reported that Nigella sativa suppresses potassium bromate-induced renal oxidative damage. In the present study, we report the chemopreventive effect of Nigella sativa against ferric nitrilotriacetate (Fe-NTA)-induced renal oxidative stress, hyperproliferative response and renal carcinogenesis. Fe-NTA (9 mg Fe/kg body weight, intraperitoneally) enhances renal lipid peroxidation, xanthine oxidase, gamma-glutamyl transpeptidase and hydrogen peroxide (H2O2) generation with reduction in renal glutathione content, antioxidant enzymes and phase II metabolizing enzymes. It also caused increase in blood urea nitrogen, serum creatinine, ornithine decarboxylase (ODC) activity and thymidine [H] incorporation into renal DNA. It also enhanced DEN (N-diethylnitrosamine)-initiated renal carcinogenesis by increasing the percentage incidence of tumours. Treatment of rats orally with Nigella sativa (50 and 100 mg/kg body weight) resulted in significant decrease in gamma-glutamyl transpeptidase, lipid peroxidation, xanthine oxidase, H2O2 generation, blood urea nitrogen, serum creatinine, renal ODC activity, DNA synthesis (P<0.001) and incidence of tumours. Renal glutathione content (P<0.01), glutathione-metabolizing enzymes (P<0.001) and antioxidant enzymes were also recovered to significant levels (P<0.001). Thus, our data suggest that Nigella sativa is a potent chemopreventive agent and suppresses Fe-NTA-induced oxidative stress, hyperproliferative response and renal carcinogenesis in Wistar rats.

Study on prevention of two-stage skin carcinogenesis by Hibiscus rosa sinensis extract and the role of its chemical constituent, gentisic acid, in the inhibition of tumour promotion response and oxidative stress in mice.

We designed the present study to investigate the role of gentisic acid in the chemopreventive activity of Hibiscus rosa sinensis extract on 7,12-dimethyl benz(a)anthracene (DMBA)/croton oil-mediated carcinogenesis in mouse skin via 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced tumour promotion response and oxidative stress. Single topical application of DMBA followed by twice weekly applications of croton oil after one week for 20 weeks resulted in 100% incidence of tumours in animals in 15 weeks. However, application of H. rosa sinensis extract 30 minutes prior to the application of croton oil twice weekly for 20 weeks caused significant reduction in the number of tumours per mouse and the percentage of tumour-bearing mice. Also, the latency period for the appearance of the first tumour was delayed on H. rosa sinensis pretreatment. A single topical application of TPA caused significant depletion in reduced glutathione (GSH) content, activities of its metabolizing and antioxidant enzymes, while malondialdehyde (MDA) formation, H2O2 content, ornithine decarboxylase (ODC) activity and DNA synthesis were significantly increased. Interestingly, pretreatment of H. rosa sinensis extract (3.5 mg and 7 mg/kg body weight) and gentisic acid (2.0 microg and 4.0 microg/0.2 ml acetone per animal) restored the levels of GSH, and its metabolizing and antioxidant enzymes (P<0.05). There was also a statistically significant reduction in MDA formation and H2O2 content (P<0.05) at both doses. Although inhibition of ODC activity by gentisic acid was not dose-dependent, thymidine incorporation in DNA (P<0.05) was dose-dependently recovered by the plant extract and its chemical constituent. We therefore propose that gentisic acid has a role in the modulatory activity of H. rosa sinensis extract.

Tephrosia purpurea ameliorates N-diethylnitrosamine and potassium bromate-mediated renal oxidative stress and toxicity in Wistar rats.

In an earlier communication, we have shown that Tephrosia purpurea ameliorates benzoyl peroxide-induced oxidative stress in murine skin (Saleem et al. 1999). The present study was designed to investigate a chemopreventive efficacy of T purpurea against N-diethylnitrosamine-initiated and potassium bromate-mediated oxidative stress and toxicity in rat kidney. A single intraperitoneal dose of N-diethylnitrosamine (200 mg/kg body weight) one hr prior to the dose of KBrO3 (125 mg/kg body weight) increases microsomal lipid peroxidation and the activity of xanthine oxidase and decreases the activities of renal antioxidant enzymes viz., catalase, glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase, phase II metabolizing enzymes such as glutathione-S-transferase and quinone reductase and causes depletion in the level of renal glutathione content. A sharp increase in blood urea nitrogen and serum creatinine has also been observed. Prophylactic treatment of rats with T. purpurea at doses of 5 mg/kg body weight and 10 mg/kg body weight prevented N-diethylnitrosamine-initiated and KBrO3 promoted renal oxidative stress and toxicity. The susceptibility of renal microsomal membrane for iron ascorbate-induced lipid peroxidation and xanthine oxidase activities were significantly reduced (P<0.01). The depleted levels of glutathione, the inhibited activities of antioxidant enzymes, phase II metabolizing enzymes and the enhanced levels of serum creatinine and blood urea nitrogen were recovered to a significant level (P<0.01). All the antioxidant enzymes were recovered dose-dependently. Our data indicate that T purpurea besides a skin antioxidant can be a potent chemopreventive agent against renal oxidative stress and carcinogenesis induced by N-diethylnitrosamine and KBrO3.