Rational use of Ashwagandha in Ayurveda (Traditional Indian Medicine) for health and healing.

ETHNOPHARMACOLOGICAL RELEVANCE: Withania somnifera (L.) Dunal (Physalis somnifera L.) is a fairly known perennial shrub of Solanaceae family, and is used in Ayurveda- Traditional Indian Medicine (TIM), since ancient times. It is well known as Ashwagandha in Sanskrit language in Ayurvedic classics. Its Mula (root) is recommended for health and healing, and the number of single and compound formulation is prescribed rationally. It is believed that the species name-somnifera is coined based on popular use to "induce sleep" in Ayurveda. AIM OF THE STUDY: The present study was aimed to bring out the experience-based traditional uses of Ashwagandha for health and healing with an emphasis on the pharmacological and biochemical scientific evidences to corroborate them. The scientific evidences have been explored from the national and international publications. MATERIALS AND METHOD: A comprehensive literary search of Ayurvedic classics was carried out systematically regarding Ashwagandha for its rationality behind the traditional uses. To excavate the subject matter, the original Ayurvedic scriptures and several standard Ayurvedic texts of different period was studied insightfully for meaningful contribution. It is to be noted that the primary source of knowledge was considered in writing this manuscript without any biased attitude. The available literature on Ashwagandha was also searched to ascertain the basis of scientific Latin name and correct identity. The Ayurvedic Pharmacopoeia and other relevant scientific works were also taken into consideration to make the subject matter more clearly to the scientific world. For the scientific evidence of the uses, the international and national Journals and other published material were also searched to make it inquisitiveness to the scholars interested in Ayurvedic medicinal plants. RESULTS: The present paper throws ancient luminosity behind the therapeutic uses of one of the promising plant drug i.e., Ashwagandha of ancient India even to the present time. The scientific evidences corroborate the rationality ascribed in available Ayurvedic classics of various period of India has been gained. CONCLUSION: The study explores that the first reference of Ashwagandha with its significant nomenclature, useful part, properties, action, and eloquent uses has its footprint in the original texts of Ayurveda. In later works enhanced knowledge with traditional uses continued even today. Several single and compound formulations have been found to maintain the health and to alleviate the disorders rationally. It is worthy to note here that the scientific evidences corroborate the uses practiced in Ayurveda.

Deregulation of hepatic lipid metabolism associated with insulin resistance in rats subjected to chronic monocrotophos exposure.

In our previous study, we demonstrated the potential of monocrotophos (MCP), an organophosphorus insecticide (OPI), to induce glucose intolerance, insulin resistance (IR), and dyslipidemia with hyperinsulinemia in rats after chronic exposure. As hyperinsulinemia is likely to exert an impact on hepatic lipid metabolism, we carried out this study to establish the effect of chronic MCP exposure (0.9 and 1.8 mg/kg/day for 180 days) on hepatic lipid metabolism in rats. The state of IR induced by MCP in rats was associated with an increase in the liver lipid content (triglyceride and cholesterol) and expression levels of sterol regulatory element-binding proteins, PPARγ, acetyl-CoA carboxylase, and fatty acid synthase in the liver. Similarly, activities of key enzymes (acetyl-COA carboxylase, fatty acid synthase, lipin 1, malic enzyme, glucose-6-phosphate dehydrogenase, and glycerol-3-phosphate dehydrogenase), which regulate lipogenesis, were enhanced in livers of pesticide-treated rats. A strong correlation was observed between insulin levels, hepatic lipid content, and plasma lipid profile in treated rats. Our study suggests that long-term exposure to OPIs not only has a propensity to induce a state of hyperinsulinemic IR, but it is also associated with augmented hepatic lipogenesis, which may explain dyslipidemia induced by chronic exposure to MCP.

Gluten contamination in labelled and naturally gluten-free grain products in southern India.

Consumption of a gluten-free diet or avoiding exposure to gluten is the only feasible and effective treatment available for coeliac patients to date. Although many grains and their products are naturally gluten-free, the possibility of gluten cross-contamination must be considered. Since such data are not available for Indian markets, we carried out this pilot study (n = 160) to assess gluten contamination in various grain-based food products from the category of breakfast products, flours, and batters made from grain that are naturally gluten free. The gluten was extracted from samples using 60% ethanol and gluten analysis was carried out using a commercially available competitive ELISA, which utilises a monoclonal antibody. Nearly 9.8% of the products labelled as gluten-free and 36.7% of the products made from naturally gluten-free grain were found to contain gluten above 20 mg/kg. Among products made from naturally gluten-free grain, 35.9% of the flour samples and 85% of the oat samples (11.67-1830 mg/kg) were contaminated with gluten. In the case of flours, unbranded samples collected from local markets (70%) and directly from local mills (30%) showed gluten content above Codex safety levels (20-400 mg/kg). Among products labelled as gluten free (n = 51), only 5 samples showed gluten contamination above 20 mg/kg although levels were well within 100 mg/kg (32.5 ± 5.8). Our study suggests that there is a likelihood of gluten contamination in products that are sourced from local retailers and millers.

Plasma paraoxonase1 activity in rats treated with monocrotophos: a study of the effect of duration of exposure.

We have earlier demonstrated the potential of monocrotophos (MCP), a highly toxic organophosphorus insecticide (OPI), to elicit insulin resistance in rats after chronic exposure. Given the understanding of role of paraoxonase1 (PON1) in OPI toxicity and diabetes pathology, this study was envisaged to understand the effect of duration of exposure to MCP on plasma PON1 activity in rats. Rats were administered MCP per os at 1/20 and 1/10th LD50 as daily doses for 180 days. Interim blood samples were collected at 15, 30, 45, 90 and 180 d for analysis of plasma parameters. Exposure to MCP for 45 resulted in persistent trend of hyperinsulinemia, while significant increase in fasting glucose levels was observed after 180 days. MCP caused suppression of plasma cholinesterase activity though the study period, albeit extent of inhibition was more severe during the early phase of the study. Exposure to MCP for 180 d resulted in hypertriglyceridemia and marginal decrease in HDL-C levels. MCP failed to modulate PON1 activity in plasma during the early phase of the study (up to 45 d). However, prolonged exposure resulted in significant increase in the plasma PON1 activity. This suggests that manifestation of insulin resistance in rats subjected to chronic exposure to MCP is associated with increase in PON1 activity. Our work provides rationale for studying whether the increase in PON1 activity observed in the present study serves to counter the deleterious effect of long term exposure to organophosphorus insecticides on metabolic homeostasis.

Protective Effect of Withania coagulans Fruit Extract on Cisplatin-induced Nephrotoxicity in Rats.

BACKGROUND: Fruits of Withania coagulans (Solanaceae) reported to possess several bioactive compounds as curative agents for various clinical conditions. Cisplatin is a chemotherapeutic drug to treat sarcomas, carcinomas, lymphomas, cervical cancer, germ cell tumors, etc. The major factor that limits its clinical use is its dose-dependent nephrotoxicity. AIM: To explore the nephroprotective effect of W. coagulans extract and its modulatory effects against cisplatin-induced nephrotoxicity and genotoxicity. MATERIALS AND METHODS: W. coagulans fruit extract was quantitatively standardized with withaferin A using high-performance thin-layer chromatography. The subacute toxicity study was performed according to OECD guidelines in experimental rats. Nephrotoxicity in rats was induced by a single dose of cisplatin (6 mg/kg, intraperitoneal). Nephroprotective role of W. coagulans fruit extract at different doses had been evaluated. It includes quantification of serum kidney toxicity markers, renal tissue oxidative stress biomarkers and pro-inflammatory cytokines level, DNA fragmentation assay, and histopathological examination of renal tissue. RESULTS: Withaferin A was found 3.56 mg/g of W. coagulans fruit extract. It significantly prevented the rise in serum urea and creatinine level and also preserve rat kidneys from oxidative stress and free radical induced DNA damage. Histopathological study showed extract treatment eliminates tubular swelling, cellular necrosis, and protein cast deposition in cisplatin treated kidney tissue. It averted the decline in glutathione content, activities of superoxide dismutase and catalase. These parameters were restored to near normal levels by extract in a dose of 400 mg/kg, per oral. Conclusion: It can be justified that W. coagulans possess dose dependent protective effect against cisplatin induced kidney damages, primarily through its free radical scavenging and anti inflammatory activity. SUMMARY: Authentication and standardization of Withania coagulans fruitsSubacute oral toxicity studyEvaluation of nephroprotective activity against cisplatin-induced nephrotoxicityDNA fragmentation assay and histopathological examination of kidney tissue in experimental rats. Abbreviations Used: WHO: World Health Organization, SOD: Superoxide dismutase, CAT: Catalase, HPTLC: High-performance thin layer chromatography, p.o.: Per.oral, i.p.: Intraperitoneal, TNF-α: Tumor necrosis factor-alpha, IL-1ß: Interleukin 1-beta, IL-6: Interleukin-6.

Anti-psoriatic potential of Solanum xanthocarpum stem in Imiquimod-induced psoriatic mice model.

ETHNOPHARMACOLOGICAL RELEVANCE: The plant Solanum xanthocarpum Schrad. & Wendl. (Solanaceae) is one of the members of the dashamula (ten roots) in Ayurvedic system of medicine. The stem and fruits are used as an antipyretic, antiasthmatic and is prescribed in skin infections and for relief in burning sensation in the feet accompanied by vesicular eruptions. OBJECTIVE: To scientifically validate the anti-psoriatic potential of Solanum xanthocarpum stem in Imiquimod-induced psoriatic mice model. MATERIALS AND METHODS: Ethanolic stems extract of Solanum xanthocarpum (ESX) was first subjected to phytochemical screening and quantification of identified phytoconstituents, which was further standardized with the help of HPTLC using chlorogenic acid as a marker. The extract was then subjected to acute oral toxicity and skin irritability study for determining the safety profile of the extract. Imiquimod-induced psoriatic mouse model was then performed to check the efficacy of extract against psoriasis, where treatment was carried out for 15 days both topically (Gel at 2.5%, 5% and 10%) as well as orally (at 100, 200 and 400mg/kg p.o.) and their Psoriasis Area Severity Index (PASI) was calculated. The study also included determination of levels of TNF-α, IL-1ß, IL-6 and IL-17 in the animal tissues, which further included biochemical evaluations such as total collagen, hexosamine, hyaluronic acid DNA, protein antioxidant profiles such as lipid peroxidation, nitric oxide, superoxide dismutase and catalase along with histopathological studies of the tissues. RESULT: ESX showed the presence of mainly phenols, tannins, flavonoids, alkaloids and carbohydrates, while chlorogenic acid was reported to be 3.49% w/w. The Imiquimod-induced psoriatic mouse model, depicted a potent anti-psoriatic activity of the extract both topical (10%) and oral (200 and 400mg/kg p.o., as evident through PASI grading The effect was found to be more prominent in case of topically treated as compared to orally treated mice. The results also showed a significant inhibition in the expression of TNF-α, IL-1ß, IL-6 and IL-17 in treated animal tissues and also showed significant restoration of the altered biochemical parameters along with reduced hyperkeratinisation as observed through histopathology. CONCLUSION: The study scientifically justified the anti-psoriatic activity of the ESX, which may be attributed to inhibition in the expression of cytokines such as TNF-α, IL-1ß, IL-6 and IL-17. Further, the observed antioxidant, antimicrobial and cellular proliferative activities may act as a contributing factor in treatment of psoriasis, which may be attributed to the presence of chlorogenic acid along with other phytochemicals in combination.

The Ayurvedic Pharmacopoeia of India, development and perspectives.

ETHNOPHARMACOLOGICAL RELEVANCE: The Ayurvedic Pharmacopoeia of India (API) is a unique book of standards describing the quality, purity and strength of selected drugs that are manufactured, distributed, and sold by the licensed manufacturers in pan India. It is developed in two parts; the part one comprises of mono-monographs of medicinal substances of natural origin and part two includes selected compound formulations sourced from the schedule - I books under the Drugs and Cosmetics Act, 1940 comprising of popular Ayurvedic classics of different period of times. The first part of the Ayurvedic Formulary of India was published in 1978 and thereafter, the Ayurvedic Pharmacopoeia of India (mono-monograph) Part-I, Vol. I was published in the year 1989 and subsequently, the other volumes were published with their legalized status under Drugs and Cosmetics Act, 1940. AIM OF THE STUDY: The study was aimed to bring out the existing knowledge on the Ayurvedic pharmacopoeia with its chronological development reviewed from the ancient Vedic Compendia with its continuum in Ayurvedic classics of different period of time till recent past. MATERIALS AND METHODS: A literary search based on the ancient origin of Ayurveda was carried out. The drug making from the natural resources and utility of the knowledge exist in classical Ayurvedic works of different period of time till composition of the Ayurvedic Pharmacopoeia of India and its importance as official documents of Govt. of India for Standards of Ayurvedic Drugs and its perspectives have been discussed. RESULTS: The present paper reviews on the systemic development and different aspects of drug-making (Pharmacopoeia) with evidence lying in the 5000 years old work of India. During the systematic review of the various works of different period of times (ancient, medieval and modern), it was found that the Ayurvedic Pharmacopoeia of India has its development during 20th Century as an official document of Govt. of India comprising of single drugs monograph and compound formulations. CONCLUSION: In India, the development of the Indian Pharmacopoeia started in 20th Century on the recommendation of the Col. R.N. Chopra Committee and in 1978 the first part of the Ayurvedic formulary of India was published. Subsequently, the amendment in the drugs and cosmetics Act 1940 was brought in 1964 for regulation of the drugs in Indian Systems of Medicine (Ayurveda, Unani and Siddha). Later on the Ayurvedic Pharmacopoeia of India (Mono-Monograph) Part-I, Volume I, was published in the year 1989 and the other volumes were published subsequently in different years.

Characterization of age-dependent changes in the striatum: Response to the mitochondrial toxin 3-nitropropionic acid.

Neurodegenerative phenomena are associated with mitochondrial dysfunction and this could be exacerbated by aging. Age-dependence of mitochondrial response to toxins could help understand these mechanisms and evolve novel therapeutics. 3-Nitropropionic acid (3-NPA) is a mitochondrial toxin that induces neurotoxicity in the striatum via inhibition of complex II. We investigated the age-related events that contribute to 3-NPA toxicity. 3-NPA induced neuronal death, oxidative stress and altered mitochondrial structure in neuronal cells. 3-NPA injection in vivo caused motor impairment, mitochondrial dysfunction and oxidative damage with different trend in young and adult mice. To understand the age-dependent mechanisms, we carried out proteomic analysis of the striatal protein extract from young mice (control: YC vs. 3-NPA treated: YT) and adult mice (control: AC vs. 3-NPA treated: AT). Among the 3752 identified proteins, 33 differentially expressed proteins (mitochondrial, synaptic and microsomal proteins) were unique either to YT or AT. Interestingly, comparison of the proteomic profile in AC and YC indicated that 161 proteins (linked with cytoskeletal structure, neuronal development, axogenesis, protein transport, cell adhesion and synaptic function) were down-regulated in AC compared to YC. We surmise that aging contributes to the cellular and molecular architecture in the mouse striatum with implications for neurodegeneration.

Systematic investigation of ethanolic extract from Leea macrophylla: Implications in wound healing.

ETHNOPHARMACOLOGICAL RELEVANCE: Leea macrophylla Roxb. ex Hornem. (Leeaceae) commonly known as Hastikarnapalasa is mainly distributed throughout the tropical parts of India. Traditionally, the plant is found to be effective against guinea worm, ringworm and is applied to sores and wounds. AIM OF THE STUDY: The present study aims to validate traditional wound healing claim of Leea macrophylla scientifically. MATERIAL AND METHODS: Box-Behnken design (BBD) was used to optimize the extraction process. The optimized root tuber extract of Leea macrophylla was standardized with chlorogenic acid by HPLC for the first time. Both oral and topical routes were selected as administrative means for the wound healing study using excision and incision wound model. For topical treatment bioadhesive gel was formulated and characterized for mechanical and physical characteristics by texture profile analysis (TPA) and scanning electron microscopy (SEM). The effect on wound healing was also assessed by evaluating antioxidant enzymes viz. glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT), free radicals lipid peroxidation (LPO) and nitric oxide (NO), inflammatory marker myeloperoxidase (MPO), collagen markers hydroxyproline, hexosamine and hexuronic acid along with the histopathological examination. Furthermore, the effect on the level of the proinflammatory cytokines interleukin-1ß (IL-1ß), interleukin -6 (IL-6), tumor necrosis factor-α (TNF-α) and growth factor, vascular endothelial growth factor (VEGF) were determined. The expression of cell proliferation nuclear marker Ki-67 was also analyzed by Western blot analysis. RESULTS: With mesh openings Sieve no. 20, semi polar nature of solvent (92.5:7.5 ethanol-water blend) and extraction time of 18h, substantially greater extraction efficiency (29%) and phenolic yield (181.54mg/g) were obtained. The content of chlorogenic acid in ethanol extracts of Leea macrophylla was obtained as 9.01% w/w. In incision model, oral treatment with 500mg/kg ethanolic extract increased wound breaking strength by 23.41% while bioadhesive gel (5% w/v) showed a higher increase of 44.68%. Topical application produced complete wound contraction in 20 days against 22 days taken by oral treatment. Topical treatment also produced a significant (p<0.05) increase in antioxidants glutathione, superoxide dismutase and catalase whereas the level of enzymes lipid peroxidation and nitric oxide and inflammatory markers myeloperoxidase were reduced. Further advantageous effects were reflected by significantly (p<0.05) increased levels of hydroxyproline, hexosamine and hexuronic acid. Favorable effects on the level of proinflammatory cytokines interleukin-1ß, interleukin-6, tumor necrosis factor - α and growth factor, vascular endothelial growth factor were also observed. The wound healing potential of Leea macrophylla was further supported by its ability to promote cell proliferation during wound healing as demonstrated by Western blot analysis of proliferation marker Ki-67. CONCLUSION: The study justified traditional use of Leea macrophylla in wound healing and demonstrated that the bioadhesive gel of ethanolic extract produced faster and more significant healing as compared to oral treatment.

Phytochemical standardization, antioxidant, and antibacterial evaluations of Leea macrophylla: A wild edible plant.

In Ayurveda, Leea macrophylla Roxb. ex Hornem. (Leeaceae) is indicated in worm infestation, dermatopathies, wounds, inflammation, and in symptoms of diabetes. The present study aims to determine the antioxidant and antibacterial potential of ethanolic extract and its different fractions of Leea macrophylla root tubers using phytochemical profiling which is still unexplored. Quantitative estimations of different phytoconstituents along with characterization of ethanol extract using high performance liquid chromatography (HPLC) were performed using chlorogenic acid as a marker compound for the first time. The extract and its successive fractions were also evaluated for in vitro antioxidant activity using different models. The extract was further tested against a few Gram-positive and Gram-negative bacteria for its antibacterial activity. Phytochemical screening and quantitative estimations revealed the extract to be rich in alkaloid, flavonoid, phenols, and tannins, whereas chlorogenic acid quantified by HPLC in ethanol extract was 9.01% w/w. The results also indicated potential antioxidant and antibacterial activity, which was more prominent in the extract followed by its butanol fraction.

Organophosphorus insecticide, monocrotophos, possesses the propensity to induce insulin resistance in rats on chronic exposure.

BACKGROUND: Our earlier studies had shown that monocrotophos (MCP), an organophosphorus insecticide (OPI), has the propensity to augment the secondary complications associated with type-1 diabetes. The present study investigates whether rats exposed for prolonged periods to monocrotophos would develop insulin resistance mediated by alteration in glucose homeostasis. METHODS: Male rats were administered sublethal doses of monocrotophos daily for 180 days. Interim blood samples were collected to measure alteration in blood glucose and lipid profile. Rats were also subjected to glucose and insulin tolerance test and fasting blood glucose and insulin levels were measured to calculate insulin resistance by HOMA-IR method. After 180 days, the rats were also evaluated for pancreatic histology and activities of hepatic gluconeogenetic enzymes. RESULTS: Monocrotophos elicited a gradual and sustained increase in blood glucose and insulin resistance in rats with concomitant glucose intolerance and reduced insulin sensitivity. MCP exposure was also associated with increase in weights of key white adipose pads, activities of gluconeogenesis enzymes and increase in pancreatic islet diameter, all of which led to hyperglycemia, hyperinsulinemia and dyslipidaemia. CONCLUSION: Long-term exposure of rats to MCP resulted in glucose intolerance with hyperinsulinemia, a hallmark of insulin resistance. Our data suggest that chronic exposure to low doses of monocrotophos, might lead to development of insulin resistance by altering lipid profile and glucose homeostasis.

Anti-inflammatory, analgesic and anti-pyretic activities of standardized root extract of Jasminum sambac.

ETHNOPHARMACOLOGICAL RELEVANCE: The plant Jasminum sambac L. (Oleaceae) is cultivated throughout India. The leaves and roots of the plant are used traditionally in the treatment of inflammation, fever and pain. The leaves of the plant have been reported to posses significant anti-inflammatory and analgesic activities. OBJECTIVE: To scientifically validate anti-inflammatory, analgesic and anti-pyretic activities of roots from Jasminum sambac. MATERIALS AND METHODS: Ethanol root extract of Jasminum sambac (EJS) was standardized using HPTLC and was subjected to acute oral toxicity study. Further, analgesic activity of EJS at 100, 200 and 400mg/kg, p.o. was evaluated using writhing test on Swiss albino mice and tail-flick test on Charles Foster albino rats. Anti-inflammatory activity of EJS was assessed by carrageenan-induced rat paw edema, cotton pellet-induced granuloma and Freund׳s adjuvant-induced arthritis models, while antipyretic activity was evaluated using Brewer׳s yeast induced pyrexia. In addition, biochemical parameters such as alkaline phosphatase (ALP), aspartate transaminase (AST), alanine transaminase (ALT), lipid peroxidation (LPO), superoxide dismutase (SOD) and catalase (CAT) in blood serum and edematous tissue of rats exposed to acute (carrageenan) and granulomatous tissue in sub-chronic (cotton pellet granuloma) inflammation models were also evaluated. RESULTS: Phytochemical analysis of EJS revealed the presence of flavonoids, phenols, saponins, tannins and carbohydrates in major quantities, while the quantity of hesperidin in EJS (using HPTLC) was found to be 4.25%w/w. EJS at 400mg/kg, p.o. reduced writhing count up to 49.21%, whereas in tail-flick test, EJS in a dose dependent manner increased latency in flicking tail. EJS at 400mg/kg, p.o. showed significant anti-inflammatory activity after 2nd, 3rd, 4th and 6thh of treatment in carrageenan-induced edema, while a 33.58% inhibition in cotton pellet induced granuloma formation was observed at same dose level. EJS significantly (p<0.001) inhibited adjuvant-induced arthritis and also showed significant antipyretic activity. Further, a significant reversal in alterations of all the biochemical parameters (except ALP) in tissues was also observed. CONCLUSIONS: The study confirms the anti-inflammatory, analgesic and antipyretic activity of EJS which may be attributed to the presence of various phytoconstituents quantified especially hesperidin which have already been reported for its significant role in the treatment of inflammation and associated problems.

Wound-healing potential of the root extract of Albizzia lebbeck.

The present investigation is an attempt to scientifically validate the traditional use of the roots of the plant Albizzia lebbeck in Ayurvedic system of medicine for curing wounds. The study included phytochemical standardization of the ethanol root extract of A. lebbeck, which was further subjected to oral acute toxicity study. Wound-healing activity of the ethanol root extract was evaluated using incision and excision wound models. Biochemical parameters such as hydroxyproline, hexuronic acid, hexosamine, and antioxidant enzymes like superoxide dismutase, reduced glutathione and free radical parameters including lipid peroxidation and nitric oxide were evaluated on the 10th post-wounding day following dead space method. For confirmation of activity, histopathology of the wounds and granulation tissues from excision and dead space wound model were performed. The study also included assessment of antibacterial activity of ethanol root extract against strains implicated in wound infection. The ethanol root extract was found to be highly rich in flavonoids, saponins, phenols, and tannins, while the amount of rutin was found to be 4.66 % w/w. It significantly increased the wound breaking strength showing a ceiling effect at 500 mg/kg p. o. The ethanol root extract at 500 mg/kg p. o. depicted an optimum wound contraction on the 18th day, while complete wound contraction was observed at the 22nd post wound day. It also demonstrated a significant increase in dry tissue weight, total protein, hydroxyproline, hexosamine, hexuronic acid, superoxide dismutase, and reduced glutathione levels, whereas a decrease in the levels of lipid peroxidation and nitric oxide was also observed with a potential antibacterial activity. Histopathological studies revealed a normal epithelization and fibrosis which was evidenced through an increase in collagen density. Thus, the study scientifically validated the wound-healing activity of the ethanol root extract along with a potential antibacterial property which may be attributed to the enhanced collagen synthesis and a potential antioxidant activity.

Estimation of plasma triglycerides with correction for free glycerol by orlistat inhibition of lipoprotein lipase activity.

This report presents a modification of the enzymatic method (lipoprotein lipase/glycerol kinase/glycerol-3-phosphate oxidase/peroxidase) for determination of plasma triglyceride levels in order to achieve correction for the free glycerol content. The strategy is based on elimination of lipoprotein lipase activity from the single "multienzyme reagent" by use of orlistat, thereby allowing formation of quinoneimine chromophore from free glycerol. Orlistat was found to abolish the lipoprotein lipase activity (triolein was used as substrate) without any impact on the glycerol-driven rate of quinoneimine generation. Conditions were standardized for estimation of both triglyceride and glycerol content of mice plasma using a microplate reader.

Insights into the mechanisms mediating hyperglycemic and stressogenic outcomes in rats treated with monocrotophos, an organophosphorus insecticide.

The present investigation provides mechanistic insights into the hyperglycemic and stressogenic effects of monocrotophos, an organophosphorus insecticide. Pre-treatment of rats with mifepristone (glucocorticoid receptor antagonist) prevented induction of liver tyrosine aminotransferase activity (TAT), but was ineffective in attenuating hyperglycemia induced by monocrotophos. Pre-treatment with propranolol (ß-adrenergic receptor antagonist) and phentolamine (α-adrenergic receptor antagonist) were effective in abrogating monocrotophos-induced hyperglycemia. Interestingly, while propranolol offered partial protection against hyperglycemia, phentolamine completely abolished the same. However, monocrotophos-induced hyperlactacidemia was completely abolished by propranolol. Both the adrenoreceptor antagonists, however, failed to attenuate the stressogenic potential of monocrotophos. Hyperglycemia and hyperlactacidemia induced by monocrotophos were abolished by pre-treatment with atropine. Exogenous epinephrine was associated with hyperglycemia and hyperlactacidemia. The impact of adrenergic antagonists on epinephrine-induced hyperglycemia and hyperlactacidemia were remarkably similar to that of monocrotophos-induced hyperglycemia and hyperlactacidemia. Further, hydrazine sulfate (a gluconeogenesis inhibitor) abolished hyperglycemia in monocrotophos-treated rats. From our data, it can be hypothesized that excessive stimulation of adrenoreceptors, probably elicited by increased plasma epinephrine, mediates hyperglycemic outcomes induced by monocrotophos. Pattern of changes in plasma lactate suggests that ß-adrenergic activation mediates monocrotophos-induced hyperlactacidemia, while α-adrenergic receptor mediates lactate utilization, leading to hyperglycemia. Induction of liver TAT activity is attributable to glucocorticoid receptor activation as a result of hypercorticosteronemia.

Hyperglycemic and stressogenic effects of monocrotophos in rats: evidence for the involvement of acetylcholinesterase inhibition.

The purpose of this study was to investigate the involvement of acetylcholinesterase (AChE) inhibition in hyperglycemic and stressogenic effects of monocrotophos in rats. Oral administration of monocrotophos (1.8 mg/kg b.w., 1/10 LD(50)) caused reversible hyperglycemia in rats with peak increase occurring at 2 h following administration. The hyperglycemic outcome at 2 h was accompanied by significant inhibition of acetylcholinesterase (AChE) activity in brain (84%), adrenal (68%) and liver (53%) and stressogenic effects as revealed by marked increase in plasma corticosterone (102%) and liver tyrosine aminotransferase (TAT) (104%) activity. At 4 h following administration, there was normalization of hyperglycemia and hypercorticosteronemia, marginal attenuation of liver TAT activity and marked increase in liver glycogen content, without spontaneous reactivation of AChE activity in the organs studied. Interestingly, pre-treatment of rats with acetylcholine (ACh) receptor antagonists-atropine sulfate and methyl atropine nitrate offered significant protection against hyperglycemia, hypercorticosteronemia and increased liver TAT activity induced by monocrotophos. Our results clearly demonstrate the involvement of AChE inhibition in hyperglycemia and stressogenic effects of monocrotophos in rats following acute exposure. Protection offered by both, general and peripheral ACh antagonists provide further evidence for the involvement of peripheral AChE inhibition in the monocrotophos-induced effects.

Microplate-based kinetic method for assay of mitochondrial NADH-- and succinate--cytochrome c reductase activities.

This article describes a microplate-based kinetic assay for mitochondrial NADH-- and succinate--cytochrome c reductase activities in rat brain mitochondria. The assay reported here is based on the conventional spectrophotometric method and involves substrate-driven reduction of exogenous cytochrome c. Conditions regarding linearity with respect to time and protein concentration have been standardized. Furthermore, the methods were tested for inhibition of respective activities by specific inhibitors. The microplate format described here can be employed for rapid and simultaneous measurements of mitochondrial NADH-- and succinate--cytochrome c reductase activities in a large number of samples.